Eduardo Padilla / Congreso Gestion Ambiental

common.inc 303 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372 2373 2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467 2468 2469 2470 2471 2472 2473 2474 2475 2476 2477 2478 2479 2480 2481 2482 2483 2484 2485 2486 2487 2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498 2499 2500 2501 2502 2503 2504 2505 2506 2507 2508 2509 2510 2511 2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 2524 2525 2526 2527 2528 2529 2530 2531 2532 2533 2534 2535 2536 2537 2538 2539 2540 2541 2542 2543 2544 2545 2546 2547 2548 2549 2550 2551 2552 2553 2554 2555 2556 2557 2558 2559 2560 2561 2562 2563 2564 2565 2566 2567 2568 2569 2570 2571 2572 2573 2574 2575 2576 2577 2578 2579 2580 2581 2582 2583 2584 2585 2586 2587 2588 2589 2590 2591 2592 2593 2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606 2607 2608 2609 2610 2611 2612 2613 2614 2615 2616 2617 2618 2619 2620 2621 2622 2623 2624 2625 2626 2627 2628 2629 2630 2631 2632 2633 2634 2635 2636 2637 2638 2639 2640 2641 2642 2643 2644 2645 2646 2647 2648 2649 2650 2651 2652 2653 2654 2655 2656 2657 2658 2659 2660 2661 2662 2663 2664 2665 2666 2667 2668 2669 2670 2671 2672 2673 2674 2675 2676 2677 2678 2679 2680 2681 2682 2683 2684 2685 2686 2687 2688 2689 2690 2691 2692 2693 2694 2695 2696 2697 2698 2699 2700 2701 2702 2703 2704 2705 2706 2707 2708 2709 2710 2711 2712 2713 2714 2715 2716 2717 2718 2719 2720 2721 2722 2723 2724 2725 2726 2727 2728 2729 2730 2731 2732 2733 2734 2735 2736 2737 2738 2739 2740 2741 2742 2743 2744 2745 2746 2747 2748 2749 2750 2751 2752 2753 2754 2755 2756 2757 2758 2759 2760 2761 2762 2763 2764 2765 2766 2767 2768 2769 2770 2771 2772 2773 2774 2775 2776 2777 2778 2779 2780 2781 2782 2783 2784 2785 2786 2787 2788 2789 2790 2791 2792 2793 2794 2795 2796 2797 2798 2799 2800 2801 2802 2803 2804 2805 2806 2807 2808 2809 2810 2811 2812 2813 2814 2815 2816 2817 2818 2819 2820 2821 2822 2823 2824 2825 2826 2827 2828 2829 2830 2831 2832 2833 2834 2835 2836 2837 2838 2839 2840 2841 2842 2843 2844 2845 2846 2847 2848 2849 2850 2851 2852 2853 2854 2855 2856 2857 2858 2859 2860 2861 2862 2863 2864 2865 2866 2867 2868 2869 2870 2871 2872 2873 2874 2875 2876 2877 2878 2879 2880 2881 2882 2883 2884 2885 2886 2887 2888 2889 2890 2891 2892 2893 2894 2895 2896 2897 2898 2899 2900 2901 2902 2903 2904 2905 2906 2907 2908 2909 2910 2911 2912 2913 2914 2915 2916 2917 2918 2919 2920 2921 2922 2923 2924 2925 2926 2927 2928 2929 2930 2931 2932 2933 2934 2935 2936 2937 2938 2939 2940 2941 2942 2943 2944 2945 2946 2947 2948 2949 2950 2951 2952 2953 2954 2955 2956 2957 2958 2959 2960 2961 2962 2963 2964 2965 2966 2967 2968 2969 2970 2971 2972 2973 2974 2975 2976 2977 2978 2979 2980 2981 2982 2983 2984 2985 2986 2987 2988 2989 2990 2991 2992 2993 2994 2995 2996 2997 2998 2999 3000 3001 3002 3003 3004 3005 3006 3007 3008 3009 3010 3011 3012 3013 3014 3015 3016 3017 3018 3019 3020 3021 3022 3023 3024 3025 3026 3027 3028 3029 3030 3031 3032 3033 3034 3035 3036 3037 3038 3039 3040 3041 3042 3043 3044 3045 3046 3047 3048 3049 3050 3051 3052 3053 3054 3055 3056 3057 3058 3059 3060 3061 3062 3063 3064 3065 3066 3067 3068 3069 3070 3071 3072 3073 3074 3075 3076 3077 3078 3079 3080 3081 3082 3083 3084 3085 3086 3087 3088 3089 3090 3091 3092 3093 3094 3095 3096 3097 3098 3099 3100 3101 3102 3103 3104 3105 3106 3107 3108 3109 3110 3111 3112 3113 3114 3115 3116 3117 3118 3119 3120 3121 3122 3123 3124 3125 3126 3127 3128 3129 3130 3131 3132 3133 3134 3135 3136 3137 3138 3139 3140 3141 3142 3143 3144 3145 3146 3147 3148 3149 3150 3151 3152 3153 3154 3155 3156 3157 3158 3159 3160 3161 3162 3163 3164 3165 3166 3167 3168 3169 3170 3171 3172 3173 3174 3175 3176 3177 3178 3179 3180 3181 3182 3183 3184 3185 3186 3187 3188 3189 3190 3191 3192 3193 3194 3195 3196 3197 3198 3199 3200 3201 3202 3203 3204 3205 3206 3207 3208 3209 3210 3211 3212 3213 3214 3215 3216 3217 3218 3219 3220 3221 3222 3223 3224 3225 3226 3227 3228 3229 3230 3231 3232 3233 3234 3235 3236 3237 3238 3239 3240 3241 3242 3243 3244 3245 3246 3247 3248 3249 3250 3251 3252 3253 3254 3255 3256 3257 3258 3259 3260 3261 3262 3263 3264 3265 3266 3267 3268 3269 3270 3271 3272 3273 3274 3275 3276 3277 3278 3279 3280 3281 3282 3283 3284 3285 3286 3287 3288 3289 3290 3291 3292 3293 3294 3295 3296 3297 3298 3299 3300 3301 3302 3303 3304 3305 3306 3307 3308 3309 3310 3311 3312 3313 3314 3315 3316 3317 3318 3319 3320 3321 3322 3323 3324 3325 3326 3327 3328 3329 3330 3331 3332 3333 3334 3335 3336 3337 3338 3339 3340 3341 3342 3343 3344 3345 3346 3347 3348 3349 3350 3351 3352 3353 3354 3355 3356 3357 3358 3359 3360 3361 3362 3363 3364 3365 3366 3367 3368 3369 3370 3371 3372 3373 3374 3375 3376 3377 3378 3379 3380 3381 3382 3383 3384 3385 3386 3387 3388 3389 3390 3391 3392 3393 3394 3395 3396 3397 3398 3399 3400 3401 3402 3403 3404 3405 3406 3407 3408 3409 3410 3411 3412 3413 3414 3415 3416 3417 3418 3419 3420 3421 3422 3423 3424 3425 3426 3427 3428 3429 3430 3431 3432 3433 3434 3435 3436 3437 3438 3439 3440 3441 3442 3443 3444 3445 3446 3447 3448 3449 3450 3451 3452 3453 3454 3455 3456 3457 3458 3459 3460 3461 3462 3463 3464 3465 3466 3467 3468 3469 3470 3471 3472 3473 3474 3475 3476 3477 3478 3479 3480 3481 3482 3483 3484 3485 3486 3487 3488 3489 3490 3491 3492 3493 3494 3495 3496 3497 3498 3499 3500 3501 3502 3503 3504 3505 3506 3507 3508 3509 3510 3511 3512 3513 3514 3515 3516 3517 3518 3519 3520 3521 3522 3523 3524 3525 3526 3527 3528 3529 3530 3531 3532 3533 3534 3535 3536 3537 3538 3539 3540 3541 3542 3543 3544 3545 3546 3547 3548 3549 3550 3551 3552 3553 3554 3555 3556 3557 3558 3559 3560 3561 3562 3563 3564 3565 3566 3567 3568 3569 3570 3571 3572 3573 3574 3575 3576 3577 3578 3579 3580 3581 3582 3583 3584 3585 3586 3587 3588 3589 3590 3591 3592 3593 3594 3595 3596 3597 3598 3599 3600 3601 3602 3603 3604 3605 3606 3607 3608 3609 3610 3611 3612 3613 3614 3615 3616 3617 3618 3619 3620 3621 3622 3623 3624 3625 3626 3627 3628 3629 3630 3631 3632 3633 3634 3635 3636 3637 3638 3639 3640 3641 3642 3643 3644 3645 3646 3647 3648 3649 3650 3651 3652 3653 3654 3655 3656 3657 3658 3659 3660 3661 3662 3663 3664 3665 3666 3667 3668 3669 3670 3671 3672 3673 3674 3675 3676 3677 3678 3679 3680 3681 3682 3683 3684 3685 3686 3687 3688 3689 3690 3691 3692 3693 3694 3695 3696 3697 3698 3699 3700 3701 3702 3703 3704 3705 3706 3707 3708 3709 3710 3711 3712 3713 3714 3715 3716 3717 3718 3719 3720 3721 3722 3723 3724 3725 3726 3727 3728 3729 3730 3731 3732 3733 3734 3735 3736 3737 3738 3739 3740 3741 3742 3743 3744 3745 3746 3747 3748 3749 3750 3751 3752 3753 3754 3755 3756 3757 3758 3759 3760 3761 3762 3763 3764 3765 3766 3767 3768 3769 3770 3771 3772 3773 3774 3775 3776 3777 3778 3779 3780 3781 3782 3783 3784 3785 3786 3787 3788 3789 3790 3791 3792 3793 3794 3795 3796 3797 3798 3799 3800 3801 3802 3803 3804 3805 3806 3807 3808 3809 3810 3811 3812 3813 3814 3815 3816 3817 3818 3819 3820 3821 3822 3823 3824 3825 3826 3827 3828 3829 3830 3831 3832 3833 3834 3835 3836 3837 3838 3839 3840 3841 3842 3843 3844 3845 3846 3847 3848 3849 3850 3851 3852 3853 3854 3855 3856 3857 3858 3859 3860 3861 3862 3863 3864 3865 3866 3867 3868 3869 3870 3871 3872 3873 3874 3875 3876 3877 3878 3879 3880 3881 3882 3883 3884 3885 3886 3887 3888 3889 3890 3891 3892 3893 3894 3895 3896 3897 3898 3899 3900 3901 3902 3903 3904 3905 3906 3907 3908 3909 3910 3911 3912 3913 3914 3915 3916 3917 3918 3919 3920 3921 3922 3923 3924 3925 3926 3927 3928 3929 3930 3931 3932 3933 3934 3935 3936 3937 3938 3939 3940 3941 3942 3943 3944 3945 3946 3947 3948 3949 3950 3951 3952 3953 3954 3955 3956 3957 3958 3959 3960 3961 3962 3963 3964 3965 3966 3967 3968 3969 3970 3971 3972 3973 3974 3975 3976 3977 3978 3979 3980 3981 3982 3983 3984 3985 3986 3987 3988 3989 3990 3991 3992 3993 3994 3995 3996 3997 3998 3999 4000 4001 4002 4003 4004 4005 4006 4007 4008 4009 4010 4011 4012 4013 4014 4015 4016 4017 4018 4019 4020 4021 4022 4023 4024 4025 4026 4027 4028 4029 4030 4031 4032 4033 4034 4035 4036 4037 4038 4039 4040 4041 4042 4043 4044 4045 4046 4047 4048 4049 4050 4051 4052 4053 4054 4055 4056 4057 4058 4059 4060 4061 4062 4063 4064 4065 4066 4067 4068 4069 4070 4071 4072 4073 4074 4075 4076 4077 4078 4079 4080 4081 4082 4083 4084 4085 4086 4087 4088 4089 4090 4091 4092 4093 4094 4095 4096 4097 4098 4099 4100 4101 4102 4103 4104 4105 4106 4107 4108 4109 4110 4111 4112 4113 4114 4115 4116 4117 4118 4119 4120 4121 4122 4123 4124 4125 4126 4127 4128 4129 4130 4131 4132 4133 4134 4135 4136 4137 4138 4139 4140 4141 4142 4143 4144 4145 4146 4147 4148 4149 4150 4151 4152 4153 4154 4155 4156 4157 4158 4159 4160 4161 4162 4163 4164 4165 4166 4167 4168 4169 4170 4171 4172 4173 4174 4175 4176 4177 4178 4179 4180 4181 4182 4183 4184 4185 4186 4187 4188 4189 4190 4191 4192 4193 4194 4195 4196 4197 4198 4199 4200 4201 4202 4203 4204 4205 4206 4207 4208 4209 4210 4211 4212 4213 4214 4215 4216 4217 4218 4219 4220 4221 4222 4223 4224 4225 4226 4227 4228 4229 4230 4231 4232 4233 4234 4235 4236 4237 4238 4239 4240 4241 4242 4243 4244 4245 4246 4247 4248 4249 4250 4251 4252 4253 4254 4255 4256 4257 4258 4259 4260 4261 4262 4263 4264 4265 4266 4267 4268 4269 4270 4271 4272 4273 4274 4275 4276 4277 4278 4279 4280 4281 4282 4283 4284 4285 4286 4287 4288 4289 4290 4291 4292 4293 4294 4295 4296 4297 4298 4299 4300 4301 4302 4303 4304 4305 4306 4307 4308 4309 4310 4311 4312 4313 4314 4315 4316 4317 4318 4319 4320 4321 4322 4323 4324 4325 4326 4327 4328 4329 4330 4331 4332 4333 4334 4335 4336 4337 4338 4339 4340 4341 4342 4343 4344 4345 4346 4347 4348 4349 4350 4351 4352 4353 4354 4355 4356 4357 4358 4359 4360 4361 4362 4363 4364 4365 4366 4367 4368 4369 4370 4371 4372 4373 4374 4375 4376 4377 4378 4379 4380 4381 4382 4383 4384 4385 4386 4387 4388 4389 4390 4391 4392 4393 4394 4395 4396 4397 4398 4399 4400 4401 4402 4403 4404 4405 4406 4407 4408 4409 4410 4411 4412 4413 4414 4415 4416 4417 4418 4419 4420 4421 4422 4423 4424 4425 4426 4427 4428 4429 4430 4431 4432 4433 4434 4435 4436 4437 4438 4439 4440 4441 4442 4443 4444 4445 4446 4447 4448 4449 4450 4451 4452 4453 4454 4455 4456 4457 4458 4459 4460 4461 4462 4463 4464 4465 4466 4467 4468 4469 4470 4471 4472 4473 4474 4475 4476 4477 4478 4479 4480 4481 4482 4483 4484 4485 4486 4487 4488 4489 4490 4491 4492 4493 4494 4495 4496 4497 4498 4499 4500 4501 4502 4503 4504 4505 4506 4507 4508 4509 4510 4511 4512 4513 4514 4515 4516 4517 4518 4519 4520 4521 4522 4523 4524 4525 4526 4527 4528 4529 4530 4531 4532 4533 4534 4535 4536 4537 4538 4539 4540 4541 4542 4543 4544 4545 4546 4547 4548 4549 4550 4551 4552 4553 4554 4555 4556 4557 4558 4559 4560 4561 4562 4563 4564 4565 4566 4567 4568 4569 4570 4571 4572 4573 4574 4575 4576 4577 4578 4579 4580 4581 4582 4583 4584 4585 4586 4587 4588 4589 4590 4591 4592 4593 4594 4595 4596 4597 4598 4599 4600 4601 4602 4603 4604 4605 4606 4607 4608 4609 4610 4611 4612 4613 4614 4615 4616 4617 4618 4619 4620 4621 4622 4623 4624 4625 4626 4627 4628 4629 4630 4631 4632 4633 4634 4635 4636 4637 4638 4639 4640 4641 4642 4643 4644 4645 4646 4647 4648 4649 4650 4651 4652 4653 4654 4655 4656 4657 4658 4659 4660 4661 4662 4663 4664 4665 4666 4667 4668 4669 4670 4671 4672 4673 4674 4675 4676 4677 4678 4679 4680 4681 4682 4683 4684 4685 4686 4687 4688 4689 4690 4691 4692 4693 4694 4695 4696 4697 4698 4699 4700 4701 4702 4703 4704 4705 4706 4707 4708 4709 4710 4711 4712 4713 4714 4715 4716 4717 4718 4719 4720 4721 4722 4723 4724 4725 4726 4727 4728 4729 4730 4731 4732 4733 4734 4735 4736 4737 4738 4739 4740 4741 4742 4743 4744 4745 4746 4747 4748 4749 4750 4751 4752 4753 4754 4755 4756 4757 4758 4759 4760 4761 4762 4763 4764 4765 4766 4767 4768 4769 4770 4771 4772 4773 4774 4775 4776 4777 4778 4779 4780 4781 4782 4783 4784 4785 4786 4787 4788 4789 4790 4791 4792 4793 4794 4795 4796 4797 4798 4799 4800 4801 4802 4803 4804 4805 4806 4807 4808 4809 4810 4811 4812 4813 4814 4815 4816 4817 4818 4819 4820 4821 4822 4823 4824 4825 4826 4827 4828 4829 4830 4831 4832 4833 4834 4835 4836 4837 4838 4839 4840 4841 4842 4843 4844 4845 4846 4847 4848 4849 4850 4851 4852 4853 4854 4855 4856 4857 4858 4859 4860 4861 4862 4863 4864 4865 4866 4867 4868 4869 4870 4871 4872 4873 4874 4875 4876 4877 4878 4879 4880 4881 4882 4883 4884 4885 4886 4887 4888 4889 4890 4891 4892 4893 4894 4895 4896 4897 4898 4899 4900 4901 4902 4903 4904 4905 4906 4907 4908 4909 4910 4911 4912 4913 4914 4915 4916 4917 4918 4919 4920 4921 4922 4923 4924 4925 4926 4927 4928 4929 4930 4931 4932 4933 4934 4935 4936 4937 4938 4939 4940 4941 4942 4943 4944 4945 4946 4947 4948 4949 4950 4951 4952 4953 4954 4955 4956 4957 4958 4959 4960 4961 4962 4963 4964 4965 4966 4967 4968 4969 4970 4971 4972 4973 4974 4975 4976 4977 4978 4979 4980 4981 4982 4983 4984 4985 4986 4987 4988 4989 4990 4991 4992 4993 4994 4995 4996 4997 4998 4999 5000 5001 5002 5003 5004 5005 5006 5007 5008 5009 5010 5011 5012 5013 5014 5015 5016 5017 5018 5019 5020 5021 5022 5023 5024 5025 5026 5027 5028 5029 5030 5031 5032 5033 5034 5035 5036 5037 5038 5039 5040 5041 5042 5043 5044 5045 5046 5047 5048 5049 5050 5051 5052 5053 5054 5055 5056 5057 5058 5059 5060 5061 5062 5063 5064 5065 5066 5067 5068 5069 5070 5071 5072 5073 5074 5075 5076 5077 5078 5079 5080 5081 5082 5083 5084 5085 5086 5087 5088 5089 5090 5091 5092 5093 5094 5095 5096 5097 5098 5099 5100 5101 5102 5103 5104 5105 5106 5107 5108 5109 5110 5111 5112 5113 5114 5115 5116 5117 5118 5119 5120 5121 5122 5123 5124 5125 5126 5127 5128 5129 5130 5131 5132 5133 5134 5135 5136 5137 5138 5139 5140 5141 5142 5143 5144 5145 5146 5147 5148 5149 5150 5151 5152 5153 5154 5155 5156 5157 5158 5159 5160 5161 5162 5163 5164 5165 5166 5167 5168 5169 5170 5171 5172 5173 5174 5175 5176 5177 5178 5179 5180 5181 5182 5183 5184 5185 5186 5187 5188 5189 5190 5191 5192 5193 5194 5195 5196 5197 5198 5199 5200 5201 5202 5203 5204 5205 5206 5207 5208 5209 5210 5211 5212 5213 5214 5215 5216 5217 5218 5219 5220 5221 5222 5223 5224 5225 5226 5227 5228 5229 5230 5231 5232 5233 5234 5235 5236 5237 5238 5239 5240 5241 5242 5243 5244 5245 5246 5247 5248 5249 5250 5251 5252 5253 5254 5255 5256 5257 5258 5259 5260 5261 5262 5263 5264 5265 5266 5267 5268 5269 5270 5271 5272 5273 5274 5275 5276 5277 5278 5279 5280 5281 5282 5283 5284 5285 5286 5287 5288 5289 5290 5291 5292 5293 5294 5295 5296 5297 5298 5299 5300 5301 5302 5303 5304 5305 5306 5307 5308 5309 5310 5311 5312 5313 5314 5315 5316 5317 5318 5319 5320 5321 5322 5323 5324 5325 5326 5327 5328 5329 5330 5331 5332 5333 5334 5335 5336 5337 5338 5339 5340 5341 5342 5343 5344 5345 5346 5347 5348 5349 5350 5351 5352 5353 5354 5355 5356 5357 5358 5359 5360 5361 5362 5363 5364 5365 5366 5367 5368 5369 5370 5371 5372 5373 5374 5375 5376 5377 5378 5379 5380 5381 5382 5383 5384 5385 5386 5387 5388 5389 5390 5391 5392 5393 5394 5395 5396 5397 5398 5399 5400 5401 5402 5403 5404 5405 5406 5407 5408 5409 5410 5411 5412 5413 5414 5415 5416 5417 5418 5419 5420 5421 5422 5423 5424 5425 5426 5427 5428 5429 5430 5431 5432 5433 5434 5435 5436 5437 5438 5439 5440 5441 5442 5443 5444 5445 5446 5447 5448 5449 5450 5451 5452 5453 5454 5455 5456 5457 5458 5459 5460 5461 5462 5463 5464 5465 5466 5467 5468 5469 5470 5471 5472 5473 5474 5475 5476 5477 5478 5479 5480 5481 5482 5483 5484 5485 5486 5487 5488 5489 5490 5491 5492 5493 5494 5495 5496 5497 5498 5499 5500 5501 5502 5503 5504 5505 5506 5507 5508 5509 5510 5511 5512 5513 5514 5515 5516 5517 5518 5519 5520 5521 5522 5523 5524 5525 5526 5527 5528 5529 5530 5531 5532 5533 5534 5535 5536 5537 5538 5539 5540 5541 5542 5543 5544 5545 5546 5547 5548 5549 5550 5551 5552 5553 5554 5555 5556 5557 5558 5559 5560 5561 5562 5563 5564 5565 5566 5567 5568 5569 5570 5571 5572 5573 5574 5575 5576 5577 5578 5579 5580 5581 5582 5583 5584 5585 5586 5587 5588 5589 5590 5591 5592 5593 5594 5595 5596 5597 5598 5599 5600 5601 5602 5603 5604 5605 5606 5607 5608 5609 5610 5611 5612 5613 5614 5615 5616 5617 5618 5619 5620 5621 5622 5623 5624 5625 5626 5627 5628 5629 5630 5631 5632 5633 5634 5635 5636 5637 5638 5639 5640 5641 5642 5643 5644 5645 5646 5647 5648 5649 5650 5651 5652 5653 5654 5655 5656 5657 5658 5659 5660 5661 5662 5663 5664 5665 5666 5667 5668 5669 5670 5671 5672 5673 5674 5675 5676 5677 5678 5679 5680 5681 5682 5683 5684 5685 5686 5687 5688 5689 5690 5691 5692 5693 5694 5695 5696 5697 5698 5699 5700 5701 5702 5703 5704 5705 5706 5707 5708 5709 5710 5711 5712 5713 5714 5715 5716 5717 5718 5719 5720 5721 5722 5723 5724 5725 5726 5727 5728 5729 5730 5731 5732 5733 5734 5735 5736 5737 5738 5739 5740 5741 5742 5743 5744 5745 5746 5747 5748 5749 5750 5751 5752 5753 5754 5755 5756 5757 5758 5759 5760 5761 5762 5763 5764 5765 5766 5767 5768 5769 5770 5771 5772 5773 5774 5775 5776 5777 5778 5779 5780 5781 5782 5783 5784 5785 5786 5787 5788 5789 5790 5791 5792 5793 5794 5795 5796 5797 5798 5799 5800 5801 5802 5803 5804 5805 5806 5807 5808 5809 5810 5811 5812 5813 5814 5815 5816 5817 5818 5819 5820 5821 5822 5823 5824 5825 5826 5827 5828 5829 5830 5831 5832 5833 5834 5835 5836 5837 5838 5839 5840 5841 5842 5843 5844 5845 5846 5847 5848 5849 5850 5851 5852 5853 5854 5855 5856 5857 5858 5859 5860 5861 5862 5863 5864 5865 5866 5867 5868 5869 5870 5871 5872 5873 5874 5875 5876 5877 5878 5879 5880 5881 5882 5883 5884 5885 5886 5887 5888 5889 5890 5891 5892 5893 5894 5895 5896 5897 5898 5899 5900 5901 5902 5903 5904 5905 5906 5907 5908 5909 5910 5911 5912 5913 5914 5915 5916 5917 5918 5919 5920 5921 5922 5923 5924 5925 5926 5927 5928 5929 5930 5931 5932 5933 5934 5935 5936 5937 5938 5939 5940 5941 5942 5943 5944 5945 5946 5947 5948 5949 5950 5951 5952 5953 5954 5955 5956 5957 5958 5959 5960 5961 5962 5963 5964 5965 5966 5967 5968 5969 5970 5971 5972 5973 5974 5975 5976 5977 5978 5979 5980 5981 5982 5983 5984 5985 5986 5987 5988 5989 5990 5991 5992 5993 5994 5995 5996 5997 5998 5999 6000 6001 6002 6003 6004 6005 6006 6007 6008 6009 6010 6011 6012 6013 6014 6015 6016 6017 6018 6019 6020 6021 6022 6023 6024 6025 6026 6027 6028 6029 6030 6031 6032 6033 6034 6035 6036 6037 6038 6039 6040 6041 6042 6043 6044 6045 6046 6047 6048 6049 6050 6051 6052 6053 6054 6055 6056 6057 6058 6059 6060 6061 6062 6063 6064 6065 6066 6067 6068 6069 6070 6071 6072 6073 6074 6075 6076 6077 6078 6079 6080 6081 6082 6083 6084 6085 6086 6087 6088 6089 6090 6091 6092 6093 6094 6095 6096 6097 6098 6099 6100 6101 6102 6103 6104 6105 6106 6107 6108 6109 6110 6111 6112 6113 6114 6115 6116 6117 6118 6119 6120 6121 6122 6123 6124 6125 6126 6127 6128 6129 6130 6131 6132 6133 6134 6135 6136 6137 6138 6139 6140 6141 6142 6143 6144 6145 6146 6147 6148 6149 6150 6151 6152 6153 6154 6155 6156 6157 6158 6159 6160 6161 6162 6163 6164 6165 6166 6167 6168 6169 6170 6171 6172 6173 6174 6175 6176 6177 6178 6179 6180 6181 6182 6183 6184 6185 6186 6187 6188 6189 6190 6191 6192 6193 6194 6195 6196 6197 6198 6199 6200 6201 6202 6203 6204 6205 6206 6207 6208 6209 6210 6211 6212 6213 6214 6215 6216 6217 6218 6219 6220 6221 6222 6223 6224 6225 6226 6227 6228 6229 6230 6231 6232 6233 6234 6235 6236 6237 6238 6239 6240 6241 6242 6243 6244 6245 6246 6247 6248 6249 6250 6251 6252 6253 6254 6255 6256 6257 6258 6259 6260 6261 6262 6263 6264 6265 6266 6267 6268 6269 6270 6271 6272 6273 6274 6275 6276 6277 6278 6279 6280 6281 6282 6283 6284 6285 6286 6287 6288 6289 6290 6291 6292 6293 6294 6295 6296 6297 6298 6299 6300 6301 6302 6303 6304 6305 6306 6307 6308 6309 6310 6311 6312 6313 6314 6315 6316 6317 6318 6319 6320 6321 6322 6323 6324 6325 6326 6327 6328 6329 6330 6331 6332 6333 6334 6335 6336 6337 6338 6339 6340 6341 6342 6343 6344 6345 6346 6347 6348 6349 6350 6351 6352 6353 6354 6355 6356 6357 6358 6359 6360 6361 6362 6363 6364 6365 6366 6367 6368 6369 6370 6371 6372 6373 6374 6375 6376 6377 6378 6379 6380 6381 6382 6383 6384 6385 6386 6387 6388 6389 6390 6391 6392 6393 6394 6395 6396 6397 6398 6399 6400 6401 6402 6403 6404 6405 6406 6407 6408 6409 6410 6411 6412 6413 6414 6415 6416 6417 6418 6419 6420 6421 6422 6423 6424 6425 6426 6427 6428 6429 6430 6431 6432 6433 6434 6435 6436 6437 6438 6439 6440 6441 6442 6443 6444 6445 6446 6447 6448 6449 6450 6451 6452 6453 6454 6455 6456 6457 6458 6459 6460 6461 6462 6463 6464 6465 6466 6467 6468 6469 6470 6471 6472 6473 6474 6475 6476 6477 6478 6479 6480 6481 6482 6483 6484 6485 6486 6487 6488 6489 6490 6491 6492 6493 6494 6495 6496 6497 6498 6499 6500 6501 6502 6503 6504 6505 6506 6507 6508 6509 6510 6511 6512 6513 6514 6515 6516 6517 6518 6519 6520 6521 6522 6523 6524 6525 6526 6527 6528 6529 6530 6531 6532 6533 6534 6535 6536 6537 6538 6539 6540 6541 6542 6543 6544 6545 6546 6547 6548 6549 6550 6551 6552 6553 6554 6555 6556 6557 6558 6559 6560 6561 6562 6563 6564 6565 6566 6567 6568 6569 6570 6571 6572 6573 6574 6575 6576 6577 6578 6579 6580 6581 6582 6583 6584 6585 6586 6587 6588 6589 6590 6591 6592 6593 6594 6595 6596 6597 6598 6599 6600 6601 6602 6603 6604 6605 6606 6607 6608 6609 6610 6611 6612 6613 6614 6615 6616 6617 6618 6619 6620 6621 6622 6623 6624 6625 6626 6627 6628 6629 6630 6631 6632 6633 6634 6635 6636 6637 6638 6639 6640 6641 6642 6643 6644 6645 6646 6647 6648 6649 6650 6651 6652 6653 6654 6655 6656 6657 6658 6659 6660 6661 6662 6663 6664 6665 6666 6667 6668 6669 6670 6671 6672 6673 6674 6675 6676 6677 6678 6679 6680 6681 6682 6683 6684 6685 6686 6687 6688 6689 6690 6691 6692 6693 6694 6695 6696 6697 6698 6699 6700 6701 6702 6703 6704 6705 6706 6707 6708 6709 6710 6711 6712 6713 6714 6715 6716 6717 6718 6719 6720 6721 6722 6723 6724 6725 6726 6727 6728 6729 6730 6731 6732 6733 6734 6735 6736 6737 6738 6739 6740 6741 6742 6743 6744 6745 6746 6747 6748 6749 6750 6751 6752 6753 6754 6755 6756 6757 6758 6759 6760 6761 6762 6763 6764 6765 6766 6767 6768 6769 6770 6771 6772 6773 6774 6775 6776 6777 6778 6779 6780 6781 6782 6783 6784 6785 6786 6787 6788 6789 6790 6791 6792 6793 6794 6795 6796 6797 6798 6799 6800 6801 6802 6803 6804 6805 6806 6807 6808 6809 6810 6811 6812 6813 6814 6815 6816 6817 6818 6819 6820 6821 6822 6823 6824 6825 6826 6827 6828 6829 6830 6831 6832 6833 6834 6835 6836 6837 6838 6839 6840 6841 6842 6843 6844 6845 6846 6847 6848 6849 6850 6851 6852 6853 6854 6855 6856 6857 6858 6859 6860 6861 6862 6863 6864 6865 6866 6867 6868 6869 6870 6871 6872 6873 6874 6875 6876 6877 6878 6879 6880 6881 6882 6883 6884 6885 6886 6887 6888 6889 6890 6891 6892 6893 6894 6895 6896 6897 6898 6899 6900 6901 6902 6903 6904 6905 6906 6907 6908 6909 6910 6911 6912 6913 6914 6915 6916 6917 6918 6919 6920 6921 6922 6923 6924 6925 6926 6927 6928 6929 6930 6931 6932 6933 6934 6935 6936 6937 6938 6939 6940 6941 6942 6943 6944 6945 6946 6947 6948 6949 6950 6951 6952 6953 6954 6955 6956 6957 6958 6959 6960 6961 6962 6963 6964 6965 6966 6967 6968 6969 6970 6971 6972 6973 6974 6975 6976 6977 6978 6979 6980 6981 6982 6983 6984 6985 6986 6987 6988 6989 6990 6991 6992 6993 6994 6995 6996 6997 6998 6999 7000 7001 7002 7003 7004 7005 7006 7007 7008 7009 7010 7011 7012 7013 7014 7015 7016 7017 7018 7019 7020 7021 7022 7023 7024 7025 7026 7027 7028 7029 7030 7031 7032 7033 7034 7035 7036 7037 7038 7039 7040 7041 7042 7043 7044 7045 7046 7047 7048 7049 7050 7051 7052 7053 7054 7055 7056 7057 7058 7059 7060 7061 7062 7063 7064 7065 7066 7067 7068 7069 7070 7071 7072 7073 7074 7075 7076 7077 7078 7079 7080 7081 7082 7083 7084 7085 7086 7087 7088 7089 7090 7091 7092 7093 7094 7095 7096 7097 7098 7099 7100 7101 7102 7103 7104 7105 7106 7107 7108 7109 7110 7111 7112 7113 7114 7115 7116 7117 7118 7119 7120 7121 7122 7123 7124 7125 7126 7127 7128 7129 7130 7131 7132 7133 7134 7135 7136 7137 7138 7139 7140 7141 7142 7143 7144 7145 7146 7147 7148 7149 7150 7151 7152 7153 7154 7155 7156 7157 7158 7159 7160 7161 7162 7163 7164 7165 7166 7167 7168 7169 7170 7171 7172 7173 7174 7175 7176 7177 7178 7179 7180 7181 7182 7183 7184 7185 7186 7187 7188 7189 7190 7191 7192 7193 7194 7195 7196 7197 7198 7199 7200 7201 7202 7203 7204 7205 7206 7207 7208 7209 7210 7211 7212 7213 7214 7215 7216 7217 7218 7219 7220 7221 7222 7223 7224 7225 7226 7227 7228 7229 7230 7231 7232 7233 7234 7235 7236 7237 7238 7239 7240 7241 7242 7243 7244 7245 7246 7247 7248 7249 7250 7251 7252 7253 7254 7255 7256 7257 7258 7259 7260 7261 7262 7263 7264 7265 7266 7267 7268 7269 7270 7271 7272 7273 7274 7275 7276 7277 7278 7279 7280 7281 7282 7283 7284 7285 7286 7287 7288 7289 7290 7291 7292 7293 7294 7295 7296 7297 7298 7299 7300 7301 7302 7303 7304 7305 7306 7307 7308 7309 7310 7311 7312 7313 7314 7315 7316 7317 7318 7319 7320 7321 7322 7323 7324 7325 7326 7327 7328 7329 7330 7331 7332 7333 7334 7335 7336 7337 7338 7339 7340 7341 7342 7343 7344 7345 7346 7347 7348 7349 7350 7351 7352 7353 7354 7355 7356 7357 7358 7359 7360 7361 7362 7363 7364 7365 7366 7367 7368 7369 7370 7371 7372 7373 7374 7375 7376 7377 7378 7379 7380 7381 7382 7383 7384 7385 7386 7387 7388 7389 7390 7391 7392 7393 7394 7395 7396 7397 7398 7399 7400 7401 7402 7403 7404 7405 7406 7407 7408 7409 7410 7411 7412 7413 7414 7415 7416 7417 7418 7419 7420 7421 7422 7423 7424 7425 7426 7427 7428 7429 7430 7431 7432 7433 7434 7435 7436 7437 7438 7439 7440 7441 7442 7443 7444 7445 7446 7447 7448 7449 7450 7451 7452 7453 7454 7455 7456 7457 7458 7459 7460 7461 7462 7463 7464 7465 7466 7467 7468 7469 7470 7471 7472 7473 7474 7475 7476 7477 7478 7479 7480 7481 7482 7483 7484 7485 7486 7487 7488 7489 7490 7491 7492 7493 7494 7495 7496 7497 7498 7499 7500 7501 7502 7503 7504 7505 7506 7507 7508 7509 7510 7511 7512 7513 7514 7515 7516 7517 7518 7519 7520 7521 7522 7523 7524 7525 7526 7527 7528 7529 7530 7531 7532 7533 7534 7535 7536 7537 7538 7539 7540 7541 7542 7543 7544 7545 7546 7547 7548 7549 7550 7551 7552 7553 7554 7555 7556 7557 7558 7559 7560 7561 7562 7563 7564 7565 7566 7567 7568 7569 7570 7571 7572 7573 7574 7575 7576 7577 7578 7579 7580 7581 7582 7583 7584 7585 7586 7587 7588 7589 7590 7591 7592 7593 7594 7595 7596 7597 7598 7599 7600 7601 7602 7603 7604 7605 7606 7607 7608 7609 7610 7611 7612 7613 7614 7615 7616 7617 7618 7619 7620 7621 7622 7623 7624 7625 7626 7627 7628 7629 7630 7631 7632 7633 7634 7635 7636 7637 7638 7639 7640 7641 7642 7643 7644 7645 7646 7647 7648 7649 7650 7651 7652 7653 7654 7655 7656 7657 7658 7659 7660 7661 7662 7663 7664 7665 7666 7667 7668 7669 7670 7671 7672 7673 7674 7675 7676 7677 7678 7679 7680 7681 7682 7683 7684 7685 7686 7687 7688 7689 7690 7691 7692 7693 7694 7695 7696 7697 7698 7699 7700 7701 7702 7703 7704 7705 7706 7707 7708 7709 7710 7711 7712 7713 7714 7715 7716 7717 7718 7719 7720 7721 7722 7723 7724 7725 7726 7727 7728 7729 7730 7731 7732 7733 7734 7735 7736 7737 7738 7739 7740 7741 7742 7743 7744 7745 7746 7747 7748 7749 7750 7751 7752 7753 7754 7755 7756 7757 7758 7759 7760 7761 7762 7763 7764 7765 7766 7767 7768 7769 7770 7771 7772 7773 7774 7775 7776 7777 7778 7779 7780 7781 7782 7783 7784 7785 7786 7787 7788 7789 7790 7791 7792 7793 7794 7795 7796 7797 7798 7799 7800 7801 7802 7803 7804 7805 7806 7807 7808 7809 7810 7811 7812 7813 7814 7815 7816 7817 7818 7819 7820 7821 7822 7823 7824 7825 7826 7827 7828 7829 7830 7831 7832 7833 7834 7835 7836 7837 7838 7839 7840 7841 7842 7843 7844 7845 7846 7847 7848 7849 7850 7851 7852 7853 7854 7855 7856 7857 7858 7859 7860 7861 7862 7863 7864 7865 7866 7867 7868 7869 7870 7871 7872 7873 7874 7875 7876 7877 7878 7879 7880 7881 7882 7883 7884 7885 7886 7887 7888 7889 7890 7891 7892 7893 7894 7895 7896 7897 7898 7899 7900 7901 7902 7903 7904 7905 7906 7907 7908 7909 7910 7911 7912 7913 7914 7915 7916 7917 7918 7919 7920 7921 7922 7923 7924 7925 7926 7927 7928 7929 7930 7931 7932 7933 7934 7935 7936 7937 7938 7939 7940 7941 7942 7943 7944 7945 7946 7947 7948 7949 7950 7951 7952 7953 7954 7955 7956 7957 7958 7959 7960 7961 7962 7963 7964 7965 7966 7967 7968 7969 7970 7971 7972 7973 7974 7975 7976 7977 7978 7979 7980 7981 7982 7983 7984 7985 7986 7987 7988 7989 7990 7991 7992 7993 7994 7995 7996 7997 7998 7999 8000 8001 8002 8003 8004 8005 8006 8007 8008 8009 8010 8011 8012 8013 8014 8015 8016 8017 8018 8019 8020 8021 8022 8023 8024 8025 8026 8027 8028 8029 8030 8031 8032 8033 8034 8035 8036 8037 8038 8039 8040 8041 8042 8043 8044 8045 8046 8047 8048 8049 8050 8051 8052 8053 8054 8055 8056 8057 8058 8059 8060 8061 8062 8063 8064 8065 8066 8067 8068 8069 8070 8071 8072 8073 8074 8075 8076 8077 8078 8079 8080 8081 8082 8083 8084 8085 8086 8087 8088 8089 8090 8091 8092 8093 8094 8095 8096 8097 8098 8099 8100 8101 8102 8103 8104 8105 8106 8107 8108 8109 8110 8111 8112 8113 8114 8115 8116 8117 8118 8119 8120 8121 8122 8123 8124 8125 8126 8127 8128 8129 8130 8131 8132 8133 8134 8135 8136 8137 8138 8139 8140 8141 8142 8143 8144 8145 8146 8147 8148 8149 8150 8151 8152 8153 8154 8155 8156 8157 8158 8159 8160 8161 8162 8163 8164 8165 8166 8167 8168 8169 8170 8171 8172 8173 8174 8175 8176 8177 8178 8179 8180 8181 8182 8183 8184 8185 8186 8187 8188 8189 8190 8191 8192 8193 8194 8195 8196 8197 8198 8199 8200 8201 8202 8203 8204 8205 8206 8207 8208 8209 8210 8211 8212 8213 8214 8215 8216 8217 8218 8219 8220 8221 8222 8223 8224 8225 8226 8227 8228 8229 8230 8231 8232 8233 8234 8235 8236 8237 8238 8239 8240 8241 8242 8243 8244 8245 8246 8247 8248 8249 8250 8251 8252 8253 8254 8255 8256 8257 8258 8259 8260 8261 8262 8263 8264 8265 8266 8267 8268 8269 8270 8271 8272 8273 8274 8275 8276 8277 8278 8279 8280 8281 8282 8283 8284 8285 8286 8287 8288 8289 8290 8291 8292 8293 8294 8295 8296 8297 8298 8299 8300 8301 8302 8303 8304 8305 8306 8307 8308 8309 8310 8311 8312 8313 8314 8315 8316 8317 8318 8319 8320 8321 8322 8323 8324 8325 8326 8327 8328 8329 8330 8331 8332 8333 8334 8335 8336 8337 8338 8339 8340 8341 8342 8343 8344 8345 8346 8347 8348 8349 8350 8351 8352 8353 8354 8355 8356 8357 8358 8359 8360 8361 8362 8363 8364 8365 8366 8367 8368 8369 8370 8371 8372 8373 8374 8375 8376 8377 8378 8379 8380 8381 8382 8383 8384 8385 8386 8387 8388 8389 8390 8391 8392 
<?php

/**
 * @file
 * Common functions that many Drupal modules will need to reference.
 *
 * The functions that are critical and need to be available even when serving
 * a cached page are instead located in bootstrap.inc.
 */

/**
 * @defgroup php_wrappers PHP wrapper functions
 * @{
 * Functions that are wrappers or custom implementations of PHP functions.
 *
 * Certain PHP functions should not be used in Drupal. Instead, Drupal's
 * replacement functions should be used.
 *
 * For example, for improved or more secure UTF8-handling, or RFC-compliant
 * handling of URLs in Drupal.
 *
 * For ease of use and memorizing, all these wrapper functions use the same name
 * as the original PHP function, but prefixed with "drupal_". Beware, however,
 * that not all wrapper functions support the same arguments as the original
 * functions.
 *
 * You should always use these wrapper functions in your code.
 *
 * Wrong:
 * @code
 *   $my_substring = substr($original_string, 0, 5);
 * @endcode
 *
 * Correct:
 * @code
 *   $my_substring = drupal_substr($original_string, 0, 5);
 * @endcode
 *
 * @}
 */

/**
 * Return status for saving which involved creating a new item.
 */
define('SAVED_NEW', 1);

/**
 * Return status for saving which involved an update to an existing item.
 */
define('SAVED_UPDATED', 2);

/**
 * Return status for saving which deleted an existing item.
 */
define('SAVED_DELETED', 3);

/**
 * The default group for system CSS files added to the page.
 */
define('CSS_SYSTEM', -100);

/**
 * The default group for module CSS files added to the page.
 */
define('CSS_DEFAULT', 0);

/**
 * The default group for theme CSS files added to the page.
 */
define('CSS_THEME', 100);

/**
 * The default group for JavaScript and jQuery libraries added to the page.
 */
define('JS_LIBRARY', -100);

/**
 * The default group for module JavaScript code added to the page.
 */
define('JS_DEFAULT', 0);

/**
 * The default group for theme JavaScript code added to the page.
 */
define('JS_THEME', 100);

/**
 * Error code indicating that the request exceeded the specified timeout.
 *
 * @see drupal_http_request()
 */
define('HTTP_REQUEST_TIMEOUT', -1);

/**
 * @defgroup block_caching Block Caching
 * @{
 * Constants that define each block's caching state.
 *
 * Modules specify how their blocks can be cached in their hook_block_info()
 * implementations. Caching can be turned off (DRUPAL_NO_CACHE), managed by the
 * module declaring the block (DRUPAL_CACHE_CUSTOM), or managed by the core
 * Block module. If the Block module is managing the cache, you can specify that
 * the block is the same for every page and user (DRUPAL_CACHE_GLOBAL), or that
 * it can change depending on the page (DRUPAL_CACHE_PER_PAGE) or by user
 * (DRUPAL_CACHE_PER_ROLE or DRUPAL_CACHE_PER_USER). Page and user settings can
 * be combined with a bitwise-binary or operator; for example,
 * DRUPAL_CACHE_PER_ROLE | DRUPAL_CACHE_PER_PAGE means that the block can change
 * depending on the user role or page it is on.
 *
 * The block cache is cleared in cache_clear_all(), and uses the same clearing
 * policy than page cache (node, comment, user, taxonomy added or updated...).
 * Blocks requiring more fine-grained clearing might consider disabling the
 * built-in block cache (DRUPAL_NO_CACHE) and roll their own.
 *
 * Note that user 1 is excluded from block caching.
 */

/**
 * The block should not get cached.
 *
 * This setting should be used:
 * - For simple blocks (notably those that do not perform any db query), where
 *   querying the db cache would be more expensive than directly generating the
 *   content.
 * - For blocks that change too frequently.
 */
define('DRUPAL_NO_CACHE', -1);

/**
 * The block is handling its own caching in its hook_block_view().
 *
 * This setting is useful when time based expiration is needed or a site uses a
 * node access which invalidates standard block cache.
 */
define('DRUPAL_CACHE_CUSTOM', -2);

/**
 * The block or element can change depending on the user's roles.
 *
 * This is the default setting for blocks, used when the block does not specify
 * anything.
 */
define('DRUPAL_CACHE_PER_ROLE', 0x0001);

/**
 * The block or element can change depending on the user.
 *
 * This setting can be resource-consuming for sites with large number of users,
 * and thus should only be used when DRUPAL_CACHE_PER_ROLE is not sufficient.
 */
define('DRUPAL_CACHE_PER_USER', 0x0002);

/**
 * The block or element can change depending on the page being viewed.
 */
define('DRUPAL_CACHE_PER_PAGE', 0x0004);

/**
 * The block or element is the same for every user and page that it is visible.
 */
define('DRUPAL_CACHE_GLOBAL', 0x0008);

/**
 * @} End of "defgroup block_caching".
 */

/**
 * Adds content to a specified region.
 *
 * @param $region
 *   Page region the content is added to.
 * @param $data
 *   Content to be added.
 */
function drupal_add_region_content($region = NULL, $data = NULL) {
  static $content = array();

  if (isset($region) && isset($data)) {
    $content[$region][] = $data;
  }
  return $content;
}

/**
 * Gets assigned content for a given region.
 *
 * @param $region
 *   A specified region to fetch content for. If NULL, all regions will be
 *   returned.
 * @param $delimiter
 *   Content to be inserted between imploded array elements.
 */
function drupal_get_region_content($region = NULL, $delimiter = ' ') {
  $content = drupal_add_region_content();
  if (isset($region)) {
    if (isset($content[$region]) && is_array($content[$region])) {
      return implode($delimiter, $content[$region]);
    }
  }
  else {
    foreach (array_keys($content) as $region) {
      if (is_array($content[$region])) {
        $content[$region] = implode($delimiter, $content[$region]);
      }
    }
    return $content;
  }
}

/**
 * Gets the name of the currently active installation profile.
 *
 * When this function is called during Drupal's initial installation process,
 * the name of the profile that's about to be installed is stored in the global
 * installation state. At all other times, the standard Drupal systems variable
 * table contains the name of the current profile, and we can call
 * variable_get() to determine what one is active.
 *
 * @return $profile
 *   The name of the installation profile.
 */
function drupal_get_profile() {
  global $install_state;

  if (isset($install_state['parameters']['profile'])) {
    $profile = $install_state['parameters']['profile'];
  }
  else {
    $profile = variable_get('install_profile', 'standard');
  }

  return $profile;
}


/**
 * Sets the breadcrumb trail for the current page.
 *
 * @param $breadcrumb
 *   Array of links, starting with "home" and proceeding up to but not including
 *   the current page.
 */
function drupal_set_breadcrumb($breadcrumb = NULL) {
  $stored_breadcrumb = &drupal_static(__FUNCTION__);

  if (isset($breadcrumb)) {
    $stored_breadcrumb = $breadcrumb;
  }
  return $stored_breadcrumb;
}

/**
 * Gets the breadcrumb trail for the current page.
 */
function drupal_get_breadcrumb() {
  $breadcrumb = drupal_set_breadcrumb();

  if (!isset($breadcrumb)) {
    $breadcrumb = menu_get_active_breadcrumb();
  }

  return $breadcrumb;
}

/**
 * Returns a string containing RDF namespace declarations for use in XML and
 * XHTML output.
 */
function drupal_get_rdf_namespaces() {
  $xml_rdf_namespaces = array();

  // Serializes the RDF namespaces in XML namespace syntax.
  if (function_exists('rdf_get_namespaces')) {
    foreach (rdf_get_namespaces() as $prefix => $uri) {
      $xml_rdf_namespaces[] = 'xmlns:' . $prefix . '="' . $uri . '"';
    }
  }
  return count($xml_rdf_namespaces) ? "\n  " . implode("\n  ", $xml_rdf_namespaces) : '';
}

/**
 * Adds output to the HEAD tag of the HTML page.
 *
 * This function can be called as long as the headers aren't sent. Pass no
 * arguments (or NULL for both) to retrieve the currently stored elements.
 *
 * @param $data
 *   A renderable array. If the '#type' key is not set then 'html_tag' will be
 *   added as the default '#type'.
 * @param $key
 *   A unique string key to allow implementations of hook_html_head_alter() to
 *   identify the element in $data. Required if $data is not NULL.
 *
 * @return
 *   An array of all stored HEAD elements.
 *
 * @see theme_html_tag()
 */
function drupal_add_html_head($data = NULL, $key = NULL) {
  $stored_head = &drupal_static(__FUNCTION__);

  if (!isset($stored_head)) {
    // Make sure the defaults, including Content-Type, come first.
    $stored_head = _drupal_default_html_head();
  }

  if (isset($data) && isset($key)) {
    if (!isset($data['#type'])) {
      $data['#type'] = 'html_tag';
    }
    $stored_head[$key] = $data;
  }
  return $stored_head;
}

/**
 * Returns elements that are always displayed in the HEAD tag of the HTML page.
 */
function _drupal_default_html_head() {
  // Add default elements. Make sure the Content-Type comes first because the
  // IE browser may be vulnerable to XSS via encoding attacks from any content
  // that comes before this META tag, such as a TITLE tag.
  $elements['system_meta_content_type'] = array(
    '#type' => 'html_tag',
    '#tag' => 'meta',
    '#attributes' => array(
      'http-equiv' => 'Content-Type',
      'content' => 'text/html; charset=utf-8',
    ),
    // Security: This always has to be output first.
    '#weight' => -1000,
  );
  // Show Drupal and the major version number in the META GENERATOR tag.
  // Get the major version.
  list($version, ) = explode('.', VERSION);
  $elements['system_meta_generator'] = array(
    '#type' => 'html_tag',
    '#tag' => 'meta',
    '#attributes' => array(
      'name' => 'Generator',
      'content' => 'Drupal ' . $version . ' (http://drupal.org)',
    ),
  );
  // Also send the generator in the HTTP header.
  $elements['system_meta_generator']['#attached']['drupal_add_http_header'][] = array('X-Generator', $elements['system_meta_generator']['#attributes']['content']);
  return $elements;
}

/**
 * Retrieves output to be displayed in the HEAD tag of the HTML page.
 */
function drupal_get_html_head() {
  $elements = drupal_add_html_head();
  drupal_alter('html_head', $elements);
  return drupal_render($elements);
}

/**
 * Adds a feed URL for the current page.
 *
 * This function can be called as long the HTML header hasn't been sent.
 *
 * @param $url
 *   An internal system path or a fully qualified external URL of the feed.
 * @param $title
 *   The title of the feed.
 */
function drupal_add_feed($url = NULL, $title = '') {
  $stored_feed_links = &drupal_static(__FUNCTION__, array());

  if (isset($url)) {
    $stored_feed_links[$url] = theme('feed_icon', array('url' => $url, 'title' => $title));

    drupal_add_html_head_link(array(
      'rel' => 'alternate',
      'type' => 'application/rss+xml',
      'title' => $title,
      // Force the URL to be absolute, for consistency with other <link> tags
      // output by Drupal.
      'href' => url($url, array('absolute' => TRUE)),
    ));
  }
  return $stored_feed_links;
}

/**
 * Gets the feed URLs for the current page.
 *
 * @param $delimiter
 *   A delimiter to split feeds by.
 */
function drupal_get_feeds($delimiter = "\n") {
  $feeds = drupal_add_feed();
  return implode($feeds, $delimiter);
}

/**
 * @defgroup http_handling HTTP handling
 * @{
 * Functions to properly handle HTTP responses.
 */

/**
 * Processes a URL query parameter array to remove unwanted elements.
 *
 * @param $query
 *   (optional) An array to be processed. Defaults to $_GET.
 * @param $exclude
 *   (optional) A list of $query array keys to remove. Use "parent[child]" to
 *   exclude nested items. Defaults to array('q').
 * @param $parent
 *   Internal use only. Used to build the $query array key for nested items.
 *
 * @return
 *   An array containing query parameters, which can be used for url().
 */
function drupal_get_query_parameters(array $query = NULL, array $exclude = array('q'), $parent = '') {
  // Set defaults, if none given.
  if (!isset($query)) {
    $query = $_GET;
  }
  // If $exclude is empty, there is nothing to filter.
  if (empty($exclude)) {
    return $query;
  }
  elseif (!$parent) {
    $exclude = array_flip($exclude);
  }

  $params = array();
  foreach ($query as $key => $value) {
    $string_key = ($parent ? $parent . '[' . $key . ']' : $key);
    if (isset($exclude[$string_key])) {
      continue;
    }

    if (is_array($value)) {
      $params[$key] = drupal_get_query_parameters($value, $exclude, $string_key);
    }
    else {
      $params[$key] = $value;
    }
  }

  return $params;
}

/**
 * Splits a URL-encoded query string into an array.
 *
 * @param $query
 *   The query string to split.
 *
 * @return
 *   An array of URL decoded couples $param_name => $value.
 */
function drupal_get_query_array($query) {
  $result = array();
  if (!empty($query)) {
    foreach (explode('&', $query) as $param) {
      $param = explode('=', $param, 2);
      $result[$param[0]] = isset($param[1]) ? rawurldecode($param[1]) : '';
    }
  }
  return $result;
}

/**
 * Parses an array into a valid, rawurlencoded query string.
 *
 * This differs from http_build_query() as we need to rawurlencode() (instead of
 * urlencode()) all query parameters.
 *
 * @param $query
 *   The query parameter array to be processed, e.g. $_GET.
 * @param $parent
 *   Internal use only. Used to build the $query array key for nested items.
 *
 * @return
 *   A rawurlencoded string which can be used as or appended to the URL query
 *   string.
 *
 * @see drupal_get_query_parameters()
 * @ingroup php_wrappers
 */
function drupal_http_build_query(array $query, $parent = '') {
  $params = array();

  foreach ($query as $key => $value) {
    $key = ($parent ? $parent . '[' . rawurlencode($key) . ']' : rawurlencode($key));

    // Recurse into children.
    if (is_array($value)) {
      $params[] = drupal_http_build_query($value, $key);
    }
    // If a query parameter value is NULL, only append its key.
    elseif (!isset($value)) {
      $params[] = $key;
    }
    else {
      // For better readability of paths in query strings, we decode slashes.
      $params[] = $key . '=' . str_replace('%2F', '/', rawurlencode($value));
    }
  }

  return implode('&', $params);
}

/**
 * Prepares a 'destination' URL query parameter for use with drupal_goto().
 *
 * Used to direct the user back to the referring page after completing a form.
 * By default the current URL is returned. If a destination exists in the
 * previous request, that destination is returned. As such, a destination can
 * persist across multiple pages.
 *
 * @return
 *   An associative array containing the key:
 *   - destination: The path provided via the destination query string or, if
 *     not available, the current path.
 *
 * @see current_path()
 * @see drupal_goto()
 */
function drupal_get_destination() {
  $destination = &drupal_static(__FUNCTION__);

  if (isset($destination)) {
    return $destination;
  }

  if (isset($_GET['destination'])) {
    $destination = array('destination' => $_GET['destination']);
  }
  else {
    $path = $_GET['q'];
    $query = drupal_http_build_query(drupal_get_query_parameters());
    if ($query != '') {
      $path .= '?' . $query;
    }
    $destination = array('destination' => $path);
  }
  return $destination;
}

/**
 * Parses a URL string into its path, query, and fragment components.
 *
 * This function splits both internal paths like @code node?b=c#d @endcode and
 * external URLs like @code https://example.com/a?b=c#d @endcode into their
 * component parts. See
 * @link http://tools.ietf.org/html/rfc3986#section-3 RFC 3986 @endlink for an
 * explanation of what the component parts are.
 *
 * Note that, unlike the RFC, when passed an external URL, this function
 * groups the scheme, authority, and path together into the path component.
 *
 * @param string $url
 *   The internal path or external URL string to parse.
 *
 * @return array
 *   An associative array containing:
 *   - path: The path component of $url. If $url is an external URL, this
 *     includes the scheme, authority, and path.
 *   - query: An array of query parameters from $url, if they exist.
 *   - fragment: The fragment component from $url, if it exists.
 *
 * @see drupal_goto()
 * @see l()
 * @see url()
 * @see http://tools.ietf.org/html/rfc3986
 *
 * @ingroup php_wrappers
 */
function drupal_parse_url($url) {
  $options = array(
    'path' => NULL,
    'query' => array(),
    'fragment' => '',
  );

  // External URLs: not using parse_url() here, so we do not have to rebuild
  // the scheme, host, and path without having any use for it.
  if (strpos($url, '://') !== FALSE) {
    // Split off everything before the query string into 'path'.
    $parts = explode('?', $url);
    $options['path'] = $parts[0];
    // If there is a query string, transform it into keyed query parameters.
    if (isset($parts[1])) {
      $query_parts = explode('#', $parts[1]);
      parse_str($query_parts[0], $options['query']);
      // Take over the fragment, if there is any.
      if (isset($query_parts[1])) {
        $options['fragment'] = $query_parts[1];
      }
    }
  }
  // Internal URLs.
  else {
    // parse_url() does not support relative URLs, so make it absolute. E.g. the
    // relative URL "foo/bar:1" isn't properly parsed.
    $parts = parse_url('http://example.com/' . $url);
    // Strip the leading slash that was just added.
    $options['path'] = substr($parts['path'], 1);
    if (isset($parts['query'])) {
      parse_str($parts['query'], $options['query']);
    }
    if (isset($parts['fragment'])) {
      $options['fragment'] = $parts['fragment'];
    }
  }
  // The 'q' parameter contains the path of the current page if clean URLs are
  // disabled. It overrides the 'path' of the URL when present, even if clean
  // URLs are enabled, due to how Apache rewriting rules work.
  if (isset($options['query']['q'])) {
    $options['path'] = $options['query']['q'];
    unset($options['query']['q']);
  }

  return $options;
}

/**
 * Encodes a Drupal path for use in a URL.
 *
 * For aesthetic reasons slashes are not escaped.
 *
 * Note that url() takes care of calling this function, so a path passed to that
 * function should not be encoded in advance.
 *
 * @param $path
 *   The Drupal path to encode.
 */
function drupal_encode_path($path) {
  return str_replace('%2F', '/', rawurlencode($path));
}

/**
 * Sends the user to a different page.
 *
 * This issues an on-site HTTP redirect. The function makes sure the redirected
 * URL is formatted correctly.
 *
 * Usually the redirected URL is constructed from this function's input
 * parameters. However you may override that behavior by setting a
 * destination in either the $_REQUEST-array (i.e. by using
 * the query string of an URI) This is used to direct the user back to
 * the proper page after completing a form. For example, after editing
 * a post on the 'admin/content'-page or after having logged on using the
 * 'user login'-block in a sidebar. The function drupal_get_destination()
 * can be used to help set the destination URL.
 *
 * Drupal will ensure that messages set by drupal_set_message() and other
 * session data are written to the database before the user is redirected.
 *
 * This function ends the request; use it instead of a return in your menu
 * callback.
 *
 * @param $path
 *   (optional) A Drupal path or a full URL, which will be passed to url() to
 *   compute the redirect for the URL.
 * @param $options
 *   (optional) An associative array of additional URL options to pass to url().
 * @param $http_response_code
 *   (optional) The HTTP status code to use for the redirection, defaults to
 *   302. The valid values for 3xx redirection status codes are defined in
 *   @link http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.3 RFC 2616 @endlink
 *   and the
 *   @link http://tools.ietf.org/html/draft-reschke-http-status-308-07 draft for the new HTTP status codes: @endlink
 *   - 301: Moved Permanently (the recommended value for most redirects).
 *   - 302: Found (default in Drupal and PHP, sometimes used for spamming search
 *     engines).
 *   - 303: See Other.
 *   - 304: Not Modified.
 *   - 305: Use Proxy.
 *   - 307: Temporary Redirect.
 *
 * @see drupal_get_destination()
 * @see url()
 */
function drupal_goto($path = '', array $options = array(), $http_response_code = 302) {
  // A destination in $_GET always overrides the function arguments.
  // We do not allow absolute URLs to be passed via $_GET, as this can be an attack vector.
  if (isset($_GET['destination']) && !url_is_external($_GET['destination'])) {
    $destination = drupal_parse_url($_GET['destination']);
    $path = $destination['path'];
    $options['query'] = $destination['query'];
    $options['fragment'] = $destination['fragment'];
  }

  drupal_alter('drupal_goto', $path, $options, $http_response_code);

  // The 'Location' HTTP header must be absolute.
  $options['absolute'] = TRUE;

  $url = url($path, $options);

  header('Location: ' . $url, TRUE, $http_response_code);

  // The "Location" header sends a redirect status code to the HTTP daemon. In
  // some cases this can be wrong, so we make sure none of the code below the
  // drupal_goto() call gets executed upon redirection.
  drupal_exit($url);
}

/**
 * Delivers a "site is under maintenance" message to the browser.
 *
 * Page callback functions wanting to report a "site offline" message should
 * return MENU_SITE_OFFLINE instead of calling drupal_site_offline(). However,
 * functions that are invoked in contexts where that return value might not
 * bubble up to menu_execute_active_handler() should call drupal_site_offline().
 */
function drupal_site_offline() {
  drupal_deliver_page(MENU_SITE_OFFLINE);
}

/**
 * Delivers a "page not found" error to the browser.
 *
 * Page callback functions wanting to report a "page not found" message should
 * return MENU_NOT_FOUND instead of calling drupal_not_found(). However,
 * functions that are invoked in contexts where that return value might not
 * bubble up to menu_execute_active_handler() should call drupal_not_found().
 */
function drupal_not_found() {
  drupal_deliver_page(MENU_NOT_FOUND);
}

/**
 * Delivers an "access denied" error to the browser.
 *
 * Page callback functions wanting to report an "access denied" message should
 * return MENU_ACCESS_DENIED instead of calling drupal_access_denied(). However,
 * functions that are invoked in contexts where that return value might not
 * bubble up to menu_execute_active_handler() should call
 * drupal_access_denied().
 */
function drupal_access_denied() {
  drupal_deliver_page(MENU_ACCESS_DENIED);
}

/**
 * Performs an HTTP request.
 *
 * This is a flexible and powerful HTTP client implementation. Correctly
 * handles GET, POST, PUT or any other HTTP requests. Handles redirects.
 *
 * @param $url
 *   A string containing a fully qualified URI.
 * @param array $options
 *   (optional) An array that can have one or more of the following elements:
 *   - headers: An array containing request headers to send as name/value pairs.
 *   - method: A string containing the request method. Defaults to 'GET'.
 *   - data: A string containing the request body, formatted as
 *     'param=value&param=value&...'. Defaults to NULL.
 *   - max_redirects: An integer representing how many times a redirect
 *     may be followed. Defaults to 3.
 *   - timeout: A float representing the maximum number of seconds the function
 *     call may take. The default is 30 seconds. If a timeout occurs, the error
 *     code is set to the HTTP_REQUEST_TIMEOUT constant.
 *   - context: A context resource created with stream_context_create().
 *
 * @return object
 *   An object that can have one or more of the following components:
 *   - request: A string containing the request body that was sent.
 *   - code: An integer containing the response status code, or the error code
 *     if an error occurred.
 *   - protocol: The response protocol (e.g. HTTP/1.1 or HTTP/1.0).
 *   - status_message: The status message from the response, if a response was
 *     received.
 *   - redirect_code: If redirected, an integer containing the initial response
 *     status code.
 *   - redirect_url: If redirected, a string containing the URL of the redirect
 *     target.
 *   - error: If an error occurred, the error message. Otherwise not set.
 *   - headers: An array containing the response headers as name/value pairs.
 *     HTTP header names are case-insensitive (RFC 2616, section 4.2), so for
 *     easy access the array keys are returned in lower case.
 *   - data: A string containing the response body that was received.
 */
function drupal_http_request($url, array $options = array()) {
  // Allow an alternate HTTP client library to replace Drupal's default
  // implementation.
  $override_function = variable_get('drupal_http_request_function', FALSE);
  if (!empty($override_function) && function_exists($override_function)) {
    return $override_function($url, $options);
  }

  $result = new stdClass();

  // Parse the URL and make sure we can handle the schema.
  $uri = @parse_url($url);

  if ($uri == FALSE) {
    $result->error = 'unable to parse URL';
    $result->code = -1001;
    return $result;
  }

  if (!isset($uri['scheme'])) {
    $result->error = 'missing schema';
    $result->code = -1002;
    return $result;
  }

  timer_start(__FUNCTION__);

  // Merge the default options.
  $options += array(
    'headers' => array(),
    'method' => 'GET',
    'data' => NULL,
    'max_redirects' => 3,
    'timeout' => 30.0,
    'context' => NULL,
  );

  // Merge the default headers.
  $options['headers'] += array(
    'User-Agent' => 'Drupal (+http://drupal.org/)',
  );

  // stream_socket_client() requires timeout to be a float.
  $options['timeout'] = (float) $options['timeout'];

  // Use a proxy if one is defined and the host is not on the excluded list.
  $proxy_server = variable_get('proxy_server', '');
  if ($proxy_server && _drupal_http_use_proxy($uri['host'])) {
    // Set the scheme so we open a socket to the proxy server.
    $uri['scheme'] = 'proxy';
    // Set the path to be the full URL.
    $uri['path'] = $url;
    // Since the URL is passed as the path, we won't use the parsed query.
    unset($uri['query']);

    // Add in username and password to Proxy-Authorization header if needed.
    if ($proxy_username = variable_get('proxy_username', '')) {
      $proxy_password = variable_get('proxy_password', '');
      $options['headers']['Proxy-Authorization'] = 'Basic ' . base64_encode($proxy_username . (!empty($proxy_password) ? ":" . $proxy_password : ''));
    }
    // Some proxies reject requests with any User-Agent headers, while others
    // require a specific one.
    $proxy_user_agent = variable_get('proxy_user_agent', '');
    // The default value matches neither condition.
    if ($proxy_user_agent === NULL) {
      unset($options['headers']['User-Agent']);
    }
    elseif ($proxy_user_agent) {
      $options['headers']['User-Agent'] = $proxy_user_agent;
    }
  }

  switch ($uri['scheme']) {
    case 'proxy':
      // Make the socket connection to a proxy server.
      $socket = 'tcp://' . $proxy_server . ':' . variable_get('proxy_port', 8080);
      // The Host header still needs to match the real request.
      $options['headers']['Host'] = $uri['host'];
      $options['headers']['Host'] .= isset($uri['port']) && $uri['port'] != 80 ? ':' . $uri['port'] : '';
      break;

    case 'http':
    case 'feed':
      $port = isset($uri['port']) ? $uri['port'] : 80;
      $socket = 'tcp://' . $uri['host'] . ':' . $port;
      // RFC 2616: "non-standard ports MUST, default ports MAY be included".
      // We don't add the standard port to prevent from breaking rewrite rules
      // checking the host that do not take into account the port number.
      $options['headers']['Host'] = $uri['host'] . ($port != 80 ? ':' . $port : '');
      break;

    case 'https':
      // Note: Only works when PHP is compiled with OpenSSL support.
      $port = isset($uri['port']) ? $uri['port'] : 443;
      $socket = 'ssl://' . $uri['host'] . ':' . $port;
      $options['headers']['Host'] = $uri['host'] . ($port != 443 ? ':' . $port : '');
      break;

    default:
      $result->error = 'invalid schema ' . $uri['scheme'];
      $result->code = -1003;
      return $result;
  }

  if (empty($options['context'])) {
    $fp = @stream_socket_client($socket, $errno, $errstr, $options['timeout']);
  }
  else {
    // Create a stream with context. Allows verification of a SSL certificate.
    $fp = @stream_socket_client($socket, $errno, $errstr, $options['timeout'], STREAM_CLIENT_CONNECT, $options['context']);
  }

  // Make sure the socket opened properly.
  if (!$fp) {
    // When a network error occurs, we use a negative number so it does not
    // clash with the HTTP status codes.
    $result->code = -$errno;
    $result->error = trim($errstr) ? trim($errstr) : t('Error opening socket @socket', array('@socket' => $socket));

    // Mark that this request failed. This will trigger a check of the web
    // server's ability to make outgoing HTTP requests the next time that
    // requirements checking is performed.
    // See system_requirements().
    variable_set('drupal_http_request_fails', TRUE);

    return $result;
  }

  // Construct the path to act on.
  $path = isset($uri['path']) ? $uri['path'] : '/';
  if (isset($uri['query'])) {
    $path .= '?' . $uri['query'];
  }

  // Only add Content-Length if we actually have any content or if it is a POST
  // or PUT request. Some non-standard servers get confused by Content-Length in
  // at least HEAD/GET requests, and Squid always requires Content-Length in
  // POST/PUT requests.
  $content_length = strlen($options['data']);
  if ($content_length > 0 || $options['method'] == 'POST' || $options['method'] == 'PUT') {
    $options['headers']['Content-Length'] = $content_length;
  }

  // If the server URL has a user then attempt to use basic authentication.
  if (isset($uri['user'])) {
    $options['headers']['Authorization'] = 'Basic ' . base64_encode($uri['user'] . (isset($uri['pass']) ? ':' . $uri['pass'] : ':'));
  }

  // If the database prefix is being used by SimpleTest to run the tests in a copied
  // database then set the user-agent header to the database prefix so that any
  // calls to other Drupal pages will run the SimpleTest prefixed database. The
  // user-agent is used to ensure that multiple testing sessions running at the
  // same time won't interfere with each other as they would if the database
  // prefix were stored statically in a file or database variable.
  $test_info = &$GLOBALS['drupal_test_info'];
  if (!empty($test_info['test_run_id'])) {
    $options['headers']['User-Agent'] = drupal_generate_test_ua($test_info['test_run_id']);
  }

  $request = $options['method'] . ' ' . $path . " HTTP/1.0\r\n";
  foreach ($options['headers'] as $name => $value) {
    $request .= $name . ': ' . trim($value) . "\r\n";
  }
  $request .= "\r\n" . $options['data'];
  $result->request = $request;
  // Calculate how much time is left of the original timeout value.
  $timeout = $options['timeout'] - timer_read(__FUNCTION__) / 1000;
  if ($timeout > 0) {
    stream_set_timeout($fp, floor($timeout), floor(1000000 * fmod($timeout, 1)));
    fwrite($fp, $request);
  }

  // Fetch response. Due to PHP bugs like http://bugs.php.net/bug.php?id=43782
  // and http://bugs.php.net/bug.php?id=46049 we can't rely on feof(), but
  // instead must invoke stream_get_meta_data() each iteration.
  $info = stream_get_meta_data($fp);
  $alive = !$info['eof'] && !$info['timed_out'];
  $response = '';

  while ($alive) {
    // Calculate how much time is left of the original timeout value.
    $timeout = $options['timeout'] - timer_read(__FUNCTION__) / 1000;
    if ($timeout <= 0) {
      $info['timed_out'] = TRUE;
      break;
    }
    stream_set_timeout($fp, floor($timeout), floor(1000000 * fmod($timeout, 1)));
    $chunk = fread($fp, 1024);
    $response .= $chunk;
    $info = stream_get_meta_data($fp);
    $alive = !$info['eof'] && !$info['timed_out'] && $chunk;
  }
  fclose($fp);

  if ($info['timed_out']) {
    $result->code = HTTP_REQUEST_TIMEOUT;
    $result->error = 'request timed out';
    return $result;
  }
  // Parse response headers from the response body.
  // Be tolerant of malformed HTTP responses that separate header and body with
  // \n\n or \r\r instead of \r\n\r\n.
  list($response, $result->data) = preg_split("/\r\n\r\n|\n\n|\r\r/", $response, 2);
  $response = preg_split("/\r\n|\n|\r/", $response);

  // Parse the response status line.
  $response_status_array = _drupal_parse_response_status(trim(array_shift($response)));
  $result->protocol = $response_status_array['http_version'];
  $result->status_message = $response_status_array['reason_phrase'];
  $code = $response_status_array['response_code'];

  $result->headers = array();

  // Parse the response headers.
  while ($line = trim(array_shift($response))) {
    list($name, $value) = explode(':', $line, 2);
    $name = strtolower($name);
    if (isset($result->headers[$name]) && $name == 'set-cookie') {
      // RFC 2109: the Set-Cookie response header comprises the token Set-
      // Cookie:, followed by a comma-separated list of one or more cookies.
      $result->headers[$name] .= ',' . trim($value);
    }
    else {
      $result->headers[$name] = trim($value);
    }
  }

  $responses = array(
    100 => 'Continue',
    101 => 'Switching Protocols',
    200 => 'OK',
    201 => 'Created',
    202 => 'Accepted',
    203 => 'Non-Authoritative Information',
    204 => 'No Content',
    205 => 'Reset Content',
    206 => 'Partial Content',
    300 => 'Multiple Choices',
    301 => 'Moved Permanently',
    302 => 'Found',
    303 => 'See Other',
    304 => 'Not Modified',
    305 => 'Use Proxy',
    307 => 'Temporary Redirect',
    400 => 'Bad Request',
    401 => 'Unauthorized',
    402 => 'Payment Required',
    403 => 'Forbidden',
    404 => 'Not Found',
    405 => 'Method Not Allowed',
    406 => 'Not Acceptable',
    407 => 'Proxy Authentication Required',
    408 => 'Request Time-out',
    409 => 'Conflict',
    410 => 'Gone',
    411 => 'Length Required',
    412 => 'Precondition Failed',
    413 => 'Request Entity Too Large',
    414 => 'Request-URI Too Large',
    415 => 'Unsupported Media Type',
    416 => 'Requested range not satisfiable',
    417 => 'Expectation Failed',
    500 => 'Internal Server Error',
    501 => 'Not Implemented',
    502 => 'Bad Gateway',
    503 => 'Service Unavailable',
    504 => 'Gateway Time-out',
    505 => 'HTTP Version not supported',
  );
  // RFC 2616 states that all unknown HTTP codes must be treated the same as the
  // base code in their class.
  if (!isset($responses[$code])) {
    $code = floor($code / 100) * 100;
  }
  $result->code = $code;

  switch ($code) {
    case 200: // OK
    case 304: // Not modified
      break;
    case 301: // Moved permanently
    case 302: // Moved temporarily
    case 307: // Moved temporarily
      $location = $result->headers['location'];
      $options['timeout'] -= timer_read(__FUNCTION__) / 1000;
      if ($options['timeout'] <= 0) {
        $result->code = HTTP_REQUEST_TIMEOUT;
        $result->error = 'request timed out';
      }
      elseif ($options['max_redirects']) {
        // Redirect to the new location.
        $options['max_redirects']--;
        $result = drupal_http_request($location, $options);
        $result->redirect_code = $code;
      }
      if (!isset($result->redirect_url)) {
        $result->redirect_url = $location;
      }
      break;
    default:
      $result->error = $result->status_message;
  }

  return $result;
}

/**
 * Splits an HTTP response status line into components.
 *
 * See the @link http://www.w3.org/Protocols/rfc2616/rfc2616-sec6.html status line definition @endlink
 * in RFC 2616.
 *
 * @param string $respone
 *   The response status line, for example 'HTTP/1.1 500 Internal Server Error'.
 *
 * @return array
 *   Keyed array containing the component parts. If the response is malformed,
 *   all possible parts will be extracted. 'reason_phrase' could be empty.
 *   Possible keys:
 *   - 'http_version'
 *   - 'response_code'
 *   - 'reason_phrase'
 */
function _drupal_parse_response_status($response) {
  $response_array = explode(' ', trim($response), 3);
  // Set up empty values.
  $result = array(
    'reason_phrase' => '',
  );
  $result['http_version'] = $response_array[0];
  $result['response_code'] = $response_array[1];
  if (isset($response_array[2])) {
    $result['reason_phrase'] = $response_array[2];
  }
  return $result;
}

/**
 * Helper function for determining hosts excluded from needing a proxy.
 *
 * @return
 *   TRUE if a proxy should be used for this host.
 */
function _drupal_http_use_proxy($host) {
  $proxy_exceptions = variable_get('proxy_exceptions', array('localhost', '127.0.0.1'));
  return !in_array(strtolower($host), $proxy_exceptions, TRUE);
}

/**
 * @} End of "HTTP handling".
 */

/**
 * Strips slashes from a string or array of strings.
 *
 * Callback for array_walk() within fix_gpx_magic().
 *
 * @param $item
 *   An individual string or array of strings from superglobals.
 */
function _fix_gpc_magic(&$item) {
  if (is_array($item)) {
    array_walk($item, '_fix_gpc_magic');
  }
  else {
    $item = stripslashes($item);
  }
}

/**
 * Strips slashes from $_FILES items.
 *
 * Callback for array_walk() within fix_gpc_magic().
 *
 * The tmp_name key is skipped keys since PHP generates single backslashes for
 * file paths on Windows systems.
 *
 * @param $item
 *   An item from $_FILES.
 * @param $key
 *   The key for the item within $_FILES.
 *
 * @see http://php.net/manual/features.file-upload.php#42280
 */
function _fix_gpc_magic_files(&$item, $key) {
  if ($key != 'tmp_name') {
    if (is_array($item)) {
      array_walk($item, '_fix_gpc_magic_files');
    }
    else {
      $item = stripslashes($item);
    }
  }
}

/**
 * Fixes double-escaping caused by "magic quotes" in some PHP installations.
 *
 * @see _fix_gpc_magic()
 * @see _fix_gpc_magic_files()
 */
function fix_gpc_magic() {
  static $fixed = FALSE;
  if (!$fixed && ini_get('magic_quotes_gpc')) {
    array_walk($_GET, '_fix_gpc_magic');
    array_walk($_POST, '_fix_gpc_magic');
    array_walk($_COOKIE, '_fix_gpc_magic');
    array_walk($_REQUEST, '_fix_gpc_magic');
    array_walk($_FILES, '_fix_gpc_magic_files');
  }
  $fixed = TRUE;
}

/**
 * @defgroup validation Input validation
 * @{
 * Functions to validate user input.
 */

/**
 * Verifies the syntax of the given e-mail address.
 *
 * This uses the
 * @link http://php.net/manual/filter.filters.validate.php PHP e-mail validation filter. @endlink
 *
 * @param $mail
 *   A string containing an e-mail address.
 *
 * @return
 *   TRUE if the address is in a valid format.
 */
function valid_email_address($mail) {
  return (bool)filter_var($mail, FILTER_VALIDATE_EMAIL);
}

/**
 * Verifies the syntax of the given URL.
 *
 * This function should only be used on actual URLs. It should not be used for
 * Drupal menu paths, which can contain arbitrary characters.
 * Valid values per RFC 3986.
 * @param $url
 *   The URL to verify.
 * @param $absolute
 *   Whether the URL is absolute (beginning with a scheme such as "http:").
 *
 * @return
 *   TRUE if the URL is in a valid format.
 */
function valid_url($url, $absolute = FALSE) {
  if ($absolute) {
    return (bool)preg_match("
      /^                                                      # Start at the beginning of the text
      (?:ftp|https?|feed):\/\/                                # Look for ftp, http, https or feed schemes
      (?:                                                     # Userinfo (optional) which is typically
        (?:(?:[\w\.\-\+!$&'\(\)*\+,;=]|%[0-9a-f]{2})+:)*      # a username or a username and password
        (?:[\w\.\-\+%!$&'\(\)*\+,;=]|%[0-9a-f]{2})+@          # combination
      )?
      (?:
        (?:[a-z0-9\-\.]|%[0-9a-f]{2})+                        # A domain name or a IPv4 address
        |(?:\[(?:[0-9a-f]{0,4}:)*(?:[0-9a-f]{0,4})\])         # or a well formed IPv6 address
      )
      (?::[0-9]+)?                                            # Server port number (optional)
      (?:[\/|\?]
        (?:[\w#!:\.\?\+=&@$'~*,;\/\(\)\[\]\-]|%[0-9a-f]{2})   # The path and query (optional)
      *)?
    $/xi", $url);
  }
  else {
    return (bool)preg_match("/^(?:[\w#!:\.\?\+=&@$'~*,;\/\(\)\[\]\-]|%[0-9a-f]{2})+$/i", $url);
  }
}

/**
 * @} End of "defgroup validation".
 */

/**
 * Registers an event for the current visitor to the flood control mechanism.
 *
 * @param $name
 *   The name of an event.
 * @param $window
 *   Optional number of seconds before this event expires. Defaults to 3600 (1
 *   hour). Typically uses the same value as the flood_is_allowed() $window
 *   parameter. Expired events are purged on cron run to prevent the flood table
 *   from growing indefinitely.
 * @param $identifier
 *   Optional identifier (defaults to the current user's IP address).
 */
function flood_register_event($name, $window = 3600, $identifier = NULL) {
  if (!isset($identifier)) {
    $identifier = ip_address();
  }
  db_insert('flood')
    ->fields(array(
      'event' => $name,
      'identifier' => $identifier,
      'timestamp' => REQUEST_TIME,
      'expiration' => REQUEST_TIME + $window,
    ))
    ->execute();
}

/**
 * Makes the flood control mechanism forget an event for the current visitor.
 *
 * @param $name
 *   The name of an event.
 * @param $identifier
 *   Optional identifier (defaults to the current user's IP address).
 */
function flood_clear_event($name, $identifier = NULL) {
  if (!isset($identifier)) {
    $identifier = ip_address();
  }
  db_delete('flood')
    ->condition('event', $name)
    ->condition('identifier', $identifier)
    ->execute();
}

/**
 * Checks whether a user is allowed to proceed with the specified event.
 *
 * Events can have thresholds saying that each user can only do that event
 * a certain number of times in a time window. This function verifies that the
 * current user has not exceeded this threshold.
 *
 * @param $name
 *   The unique name of the event.
 * @param $threshold
 *   The maximum number of times each user can do this event per time window.
 * @param $window
 *   Number of seconds in the time window for this event (default is 3600
 *   seconds, or 1 hour).
 * @param $identifier
 *   Unique identifier of the current user. Defaults to their IP address.
 *
 * @return
 *   TRUE if the user is allowed to proceed. FALSE if they have exceeded the
 *   threshold and should not be allowed to proceed.
 */
function flood_is_allowed($name, $threshold, $window = 3600, $identifier = NULL) {
  if (!isset($identifier)) {
    $identifier = ip_address();
  }
  $number = db_query("SELECT COUNT(*) FROM {flood} WHERE event = :event AND identifier = :identifier AND timestamp > :timestamp", array(
    ':event' => $name,
    ':identifier' => $identifier,
    ':timestamp' => REQUEST_TIME - $window))
    ->fetchField();
  return ($number < $threshold);
}

/**
 * @defgroup sanitization Sanitization functions
 * @{
 * Functions to sanitize values.
 *
 * See http://drupal.org/writing-secure-code for information
 * on writing secure code.
 */

/**
 * Strips dangerous protocols (e.g. 'javascript:') from a URI.
 *
 * This function must be called for all URIs within user-entered input prior
 * to being output to an HTML attribute value. It is often called as part of
 * check_url() or filter_xss(), but those functions return an HTML-encoded
 * string, so this function can be called independently when the output needs to
 * be a plain-text string for passing to t(), l(), drupal_attributes(), or
 * another function that will call check_plain() separately.
 *
 * @param $uri
 *   A plain-text URI that might contain dangerous protocols.
 *
 * @return
 *   A plain-text URI stripped of dangerous protocols. As with all plain-text
 *   strings, this return value must not be output to an HTML page without
 *   check_plain() being called on it. However, it can be passed to functions
 *   expecting plain-text strings.
 *
 * @see check_url()
 */
function drupal_strip_dangerous_protocols($uri) {
  static $allowed_protocols;

  if (!isset($allowed_protocols)) {
    $allowed_protocols = array_flip(variable_get('filter_allowed_protocols', array('ftp', 'http', 'https', 'irc', 'mailto', 'news', 'nntp', 'rtsp', 'sftp', 'ssh', 'tel', 'telnet', 'webcal')));
  }

  // Iteratively remove any invalid protocol found.
  do {
    $before = $uri;
    $colonpos = strpos($uri, ':');
    if ($colonpos > 0) {
      // We found a colon, possibly a protocol. Verify.
      $protocol = substr($uri, 0, $colonpos);
      // If a colon is preceded by a slash, question mark or hash, it cannot
      // possibly be part of the URL scheme. This must be a relative URL, which
      // inherits the (safe) protocol of the base document.
      if (preg_match('![/?#]!', $protocol)) {
        break;
      }
      // Check if this is a disallowed protocol. Per RFC2616, section 3.2.3
      // (URI Comparison) scheme comparison must be case-insensitive.
      if (!isset($allowed_protocols[strtolower($protocol)])) {
        $uri = substr($uri, $colonpos + 1);
      }
    }
  } while ($before != $uri);

  return $uri;
}

/**
 * Strips dangerous protocols from a URI and encodes it for output to HTML.
 *
 * @param $uri
 *   A plain-text URI that might contain dangerous protocols.
 *
 * @return
 *   A URI stripped of dangerous protocols and encoded for output to an HTML
 *   attribute value. Because it is already encoded, it should not be set as a
 *   value within a $attributes array passed to drupal_attributes(), because
 *   drupal_attributes() expects those values to be plain-text strings. To pass
 *   a filtered URI to drupal_attributes(), call
 *   drupal_strip_dangerous_protocols() instead.
 *
 * @see drupal_strip_dangerous_protocols()
 */
function check_url($uri) {
  return check_plain(drupal_strip_dangerous_protocols($uri));
}

/**
 * Applies a very permissive XSS/HTML filter for admin-only use.
 *
 * Use only for fields where it is impractical to use the
 * whole filter system, but where some (mainly inline) mark-up
 * is desired (so check_plain() is not acceptable).
 *
 * Allows all tags that can be used inside an HTML body, save
 * for scripts and styles.
 */
function filter_xss_admin($string) {
  return filter_xss($string, array('a', 'abbr', 'acronym', 'address', 'article', 'aside', 'b', 'bdi', 'bdo', 'big', 'blockquote', 'br', 'caption', 'cite', 'code', 'col', 'colgroup', 'command', 'dd', 'del', 'details', 'dfn', 'div', 'dl', 'dt', 'em', 'figcaption', 'figure', 'footer', 'h1', 'h2', 'h3', 'h4', 'h5', 'h6', 'header', 'hgroup', 'hr', 'i', 'img', 'ins', 'kbd', 'li', 'mark', 'menu', 'meter', 'nav', 'ol', 'output', 'p', 'pre', 'progress', 'q', 'rp', 'rt', 'ruby', 's', 'samp', 'section', 'small', 'span', 'strong', 'sub', 'summary', 'sup', 'table', 'tbody', 'td', 'tfoot', 'th', 'thead', 'time', 'tr', 'tt', 'u', 'ul', 'var', 'wbr'));
}

/**
 * Filters HTML to prevent cross-site-scripting (XSS) vulnerabilities.
 *
 * Based on kses by Ulf Harnhammar, see http://sourceforge.net/projects/kses.
 * For examples of various XSS attacks, see: http://ha.ckers.org/xss.html.
 *
 * This code does four things:
 * - Removes characters and constructs that can trick browsers.
 * - Makes sure all HTML entities are well-formed.
 * - Makes sure all HTML tags and attributes are well-formed.
 * - Makes sure no HTML tags contain URLs with a disallowed protocol (e.g.
 *   javascript:).
 *
 * @param $string
 *   The string with raw HTML in it. It will be stripped of everything that can
 *   cause an XSS attack.
 * @param $allowed_tags
 *   An array of allowed tags.
 *
 * @return
 *   An XSS safe version of $string, or an empty string if $string is not
 *   valid UTF-8.
 *
 * @see drupal_validate_utf8()
 */
function filter_xss($string, $allowed_tags = array('a', 'em', 'strong', 'cite', 'blockquote', 'code', 'ul', 'ol', 'li', 'dl', 'dt', 'dd')) {
  // Only operate on valid UTF-8 strings. This is necessary to prevent cross
  // site scripting issues on Internet Explorer 6.
  if (!drupal_validate_utf8($string)) {
    return '';
  }
  // Store the text format.
  _filter_xss_split($allowed_tags, TRUE);
  // Remove NULL characters (ignored by some browsers).
  $string = str_replace(chr(0), '', $string);
  // Remove Netscape 4 JS entities.
  $string = preg_replace('%&\s*\{[^}]*(\}\s*;?|$)%', '', $string);

  // Defuse all HTML entities.
  $string = str_replace('&', '&amp;', $string);
  // Change back only well-formed entities in our whitelist:
  // Decimal numeric entities.
  $string = preg_replace('/&amp;#([0-9]+;)/', '&#\1', $string);
  // Hexadecimal numeric entities.
  $string = preg_replace('/&amp;#[Xx]0*((?:[0-9A-Fa-f]{2})+;)/', '&#x\1', $string);
  // Named entities.
  $string = preg_replace('/&amp;([A-Za-z][A-Za-z0-9]*;)/', '&\1', $string);

  return preg_replace_callback('%
    (
    <(?=[^a-zA-Z!/])  # a lone <
    |                 # or
    <!--.*?-->        # a comment
    |                 # or
    <[^>]*(>|$)       # a string that starts with a <, up until the > or the end of the string
    |                 # or
    >                 # just a >
    )%x', '_filter_xss_split', $string);
}

/**
 * Processes an HTML tag.
 *
 * @param $m
 *   An array with various meaning depending on the value of $store.
 *   If $store is TRUE then the array contains the allowed tags.
 *   If $store is FALSE then the array has one element, the HTML tag to process.
 * @param $store
 *   Whether to store $m.
 *
 * @return
 *   If the element isn't allowed, an empty string. Otherwise, the cleaned up
 *   version of the HTML element.
 */
function _filter_xss_split($m, $store = FALSE) {
  static $allowed_html;

  if ($store) {
    $allowed_html = array_flip($m);
    return;
  }

  $string = $m[1];

  if (substr($string, 0, 1) != '<') {
    // We matched a lone ">" character.
    return '&gt;';
  }
  elseif (strlen($string) == 1) {
    // We matched a lone "<" character.
    return '&lt;';
  }

  if (!preg_match('%^<\s*(/\s*)?([a-zA-Z0-9\-]+)([^>]*)>?|(<!--.*?-->)$%', $string, $matches)) {
    // Seriously malformed.
    return '';
  }

  $slash = trim($matches[1]);
  $elem = &$matches[2];
  $attrlist = &$matches[3];
  $comment = &$matches[4];

  if ($comment) {
    $elem = '!--';
  }

  if (!isset($allowed_html[strtolower($elem)])) {
    // Disallowed HTML element.
    return '';
  }

  if ($comment) {
    return $comment;
  }

  if ($slash != '') {
    return "</$elem>";
  }

  // Is there a closing XHTML slash at the end of the attributes?
  $attrlist = preg_replace('%(\s?)/\s*$%', '\1', $attrlist, -1, $count);
  $xhtml_slash = $count ? ' /' : '';

  // Clean up attributes.
  $attr2 = implode(' ', _filter_xss_attributes($attrlist));
  $attr2 = preg_replace('/[<>]/', '', $attr2);
  $attr2 = strlen($attr2) ? ' ' . $attr2 : '';

  return "<$elem$attr2$xhtml_slash>";
}

/**
 * Processes a string of HTML attributes.
 *
 * @return
 *   Cleaned up version of the HTML attributes.
 */
function _filter_xss_attributes($attr) {
  $attrarr = array();
  $mode = 0;
  $attrname = '';

  while (strlen($attr) != 0) {
    // Was the last operation successful?
    $working = 0;

    switch ($mode) {
      case 0:
        // Attribute name, href for instance.
        if (preg_match('/^([-a-zA-Z]+)/', $attr, $match)) {
          $attrname = strtolower($match[1]);
          $skip = ($attrname == 'style' || substr($attrname, 0, 2) == 'on');
          $working = $mode = 1;
          $attr = preg_replace('/^[-a-zA-Z]+/', '', $attr);
        }
        break;

      case 1:
        // Equals sign or valueless ("selected").
        if (preg_match('/^\s*=\s*/', $attr)) {
          $working = 1; $mode = 2;
          $attr = preg_replace('/^\s*=\s*/', '', $attr);
          break;
        }

        if (preg_match('/^\s+/', $attr)) {
          $working = 1; $mode = 0;
          if (!$skip) {
            $attrarr[] = $attrname;
          }
          $attr = preg_replace('/^\s+/', '', $attr);
        }
        break;

      case 2:
        // Attribute value, a URL after href= for instance.
        if (preg_match('/^"([^"]*)"(\s+|$)/', $attr, $match)) {
          $thisval = filter_xss_bad_protocol($match[1]);

          if (!$skip) {
            $attrarr[] = "$attrname=\"$thisval\"";
          }
          $working = 1;
          $mode = 0;
          $attr = preg_replace('/^"[^"]*"(\s+|$)/', '', $attr);
          break;
        }

        if (preg_match("/^'([^']*)'(\s+|$)/", $attr, $match)) {
          $thisval = filter_xss_bad_protocol($match[1]);

          if (!$skip) {
            $attrarr[] = "$attrname='$thisval'";
          }
          $working = 1; $mode = 0;
          $attr = preg_replace("/^'[^']*'(\s+|$)/", '', $attr);
          break;
        }

        if (preg_match("%^([^\s\"']+)(\s+|$)%", $attr, $match)) {
          $thisval = filter_xss_bad_protocol($match[1]);

          if (!$skip) {
            $attrarr[] = "$attrname=\"$thisval\"";
          }
          $working = 1; $mode = 0;
          $attr = preg_replace("%^[^\s\"']+(\s+|$)%", '', $attr);
        }
        break;
    }

    if ($working == 0) {
      // Not well formed; remove and try again.
      $attr = preg_replace('/
        ^
        (
        "[^"]*("|$)     # - a string that starts with a double quote, up until the next double quote or the end of the string
        |               # or
        \'[^\']*(\'|$)| # - a string that starts with a quote, up until the next quote or the end of the string
        |               # or
        \S              # - a non-whitespace character
        )*              # any number of the above three
        \s*             # any number of whitespaces
        /x', '', $attr);
      $mode = 0;
    }
  }

  // The attribute list ends with a valueless attribute like "selected".
  if ($mode == 1 && !$skip) {
    $attrarr[] = $attrname;
  }
  return $attrarr;
}

/**
 * Processes an HTML attribute value and strips dangerous protocols from URLs.
 *
 * @param $string
 *   The string with the attribute value.
 * @param $decode
 *   (deprecated) Whether to decode entities in the $string. Set to FALSE if the
 *   $string is in plain text, TRUE otherwise. Defaults to TRUE. This parameter
 *   is deprecated and will be removed in Drupal 8. To process a plain-text URI,
 *   call drupal_strip_dangerous_protocols() or check_url() instead.
 *
 * @return
 *   Cleaned up and HTML-escaped version of $string.
 */
function filter_xss_bad_protocol($string, $decode = TRUE) {
  // Get the plain text representation of the attribute value (i.e. its meaning).
  // @todo Remove the $decode parameter in Drupal 8, and always assume an HTML
  //   string that needs decoding.
  if ($decode) {
    if (!function_exists('decode_entities')) {
      require_once DRUPAL_ROOT . '/includes/unicode.inc';
    }

    $string = decode_entities($string);
  }
  return check_plain(drupal_strip_dangerous_protocols($string));
}

/**
 * @} End of "defgroup sanitization".
 */

/**
 * @defgroup format Formatting
 * @{
 * Functions to format numbers, strings, dates, etc.
 */

/**
 * Formats an RSS channel.
 *
 * Arbitrary elements may be added using the $args associative array.
 */
function format_rss_channel($title, $link, $description, $items, $langcode = NULL, $args = array()) {
  global $language_content;
  $langcode = $langcode ? $langcode : $language_content->language;

  $output = "<channel>\n";
  $output .= ' <title>' . check_plain($title) . "</title>\n";
  $output .= ' <link>' . check_url($link) . "</link>\n";

  // The RSS 2.0 "spec" doesn't indicate HTML can be used in the description.
  // We strip all HTML tags, but need to prevent double encoding from properly
  // escaped source data (such as &amp becoming &amp;amp;).
  $output .= ' <description>' . check_plain(decode_entities(strip_tags($description))) . "</description>\n";
  $output .= ' <language>' . check_plain($langcode) . "</language>\n";
  $output .= format_xml_elements($args);
  $output .= $items;
  $output .= "</channel>\n";

  return $output;
}

/**
 * Formats a single RSS item.
 *
 * Arbitrary elements may be added using the $args associative array.
 */
function format_rss_item($title, $link, $description, $args = array()) {
  $output = "<item>\n";
  $output .= ' <title>' . check_plain($title) . "</title>\n";
  $output .= ' <link>' . check_url($link) . "</link>\n";
  $output .= ' <description>' . check_plain($description) . "</description>\n";
  $output .= format_xml_elements($args);
  $output .= "</item>\n";

  return $output;
}

/**
 * Formats XML elements.
 *
 * @param $array
 *   An array where each item represents an element and is either a:
 *   - (key => value) pair (<key>value</key>)
 *   - Associative array with fields:
 *     - 'key': element name
 *     - 'value': element contents
 *     - 'attributes': associative array of element attributes
 *
 * In both cases, 'value' can be a simple string, or it can be another array
 * with the same format as $array itself for nesting.
 */
function format_xml_elements($array) {
  $output = '';
  foreach ($array as $key => $value) {
    if (is_numeric($key)) {
      if ($value['key']) {
        $output .= ' <' . $value['key'];
        if (isset($value['attributes']) && is_array($value['attributes'])) {
          $output .= drupal_attributes($value['attributes']);
        }

        if (isset($value['value']) && $value['value'] != '') {
          $output .= '>' . (is_array($value['value']) ? format_xml_elements($value['value']) : check_plain($value['value'])) . '</' . $value['key'] . ">\n";
        }
        else {
          $output .= " />\n";
        }
      }
    }
    else {
      $output .= ' <' . $key . '>' . (is_array($value) ? format_xml_elements($value) : check_plain($value)) . "</$key>\n";
    }
  }
  return $output;
}

/**
 * Formats a string containing a count of items.
 *
 * This function ensures that the string is pluralized correctly. Since t() is
 * called by this function, make sure not to pass already-localized strings to
 * it.
 *
 * For example:
 * @code
 *   $output = format_plural($node->comment_count, '1 comment', '@count comments');
 * @endcode
 *
 * Example with additional replacements:
 * @code
 *   $output = format_plural($update_count,
 *     'Changed the content type of 1 post from %old-type to %new-type.',
 *     'Changed the content type of @count posts from %old-type to %new-type.',
 *     array('%old-type' => $info->old_type, '%new-type' => $info->new_type));
 * @endcode
 *
 * @param $count
 *   The item count to display.
 * @param $singular
 *   The string for the singular case. Make sure it is clear this is singular,
 *   to ease translation (e.g. use "1 new comment" instead of "1 new"). Do not
 *   use @count in the singular string.
 * @param $plural
 *   The string for the plural case. Make sure it is clear this is plural, to
 *   ease translation. Use @count in place of the item count, as in
 *   "@count new comments".
 * @param $args
 *   An associative array of replacements to make after translation. Instances
 *   of any key in this array are replaced with the corresponding value.
 *   Based on the first character of the key, the value is escaped and/or
 *   themed. See format_string(). Note that you do not need to include @count
 *   in this array; this replacement is done automatically for the plural case.
 * @param $options
 *   An associative array of additional options. See t() for allowed keys.
 *
 * @return
 *   A translated string.
 *
 * @see t()
 * @see format_string()
 */
function format_plural($count, $singular, $plural, array $args = array(), array $options = array()) {
  $args['@count'] = $count;
  if ($count == 1) {
    return t($singular, $args, $options);
  }

  // Get the plural index through the gettext formula.
  $index = (function_exists('locale_get_plural')) ? locale_get_plural($count, isset($options['langcode']) ? $options['langcode'] : NULL) : -1;
  // If the index cannot be computed, use the plural as a fallback (which
  // allows for most flexiblity with the replaceable @count value).
  if ($index < 0) {
    return t($plural, $args, $options);
  }
  else {
    switch ($index) {
      case "0":
        return t($singular, $args, $options);
      case "1":
        return t($plural, $args, $options);
      default:
        unset($args['@count']);
        $args['@count[' . $index . ']'] = $count;
        return t(strtr($plural, array('@count' => '@count[' . $index . ']')), $args, $options);
    }
  }
}

/**
 * Parses a given byte count.
 *
 * @param $size
 *   A size expressed as a number of bytes with optional SI or IEC binary unit
 *   prefix (e.g. 2, 3K, 5MB, 10G, 6GiB, 8 bytes, 9mbytes).
 *
 * @return
 *   An integer representation of the size in bytes.
 */
function parse_size($size) {
  $unit = preg_replace('/[^bkmgtpezy]/i', '', $size); // Remove the non-unit characters from the size.
  $size = preg_replace('/[^0-9\.]/', '', $size); // Remove the non-numeric characters from the size.
  if ($unit) {
    // Find the position of the unit in the ordered string which is the power of magnitude to multiply a kilobyte by.
    return round($size * pow(DRUPAL_KILOBYTE, stripos('bkmgtpezy', $unit[0])));
  }
  else {
    return round($size);
  }
}

/**
 * Generates a string representation for the given byte count.
 *
 * @param $size
 *   A size in bytes.
 * @param $langcode
 *   Optional language code to translate to a language other than what is used
 *   to display the page.
 *
 * @return
 *   A translated string representation of the size.
 */
function format_size($size, $langcode = NULL) {
  if ($size < DRUPAL_KILOBYTE) {
    return format_plural($size, '1 byte', '@count bytes', array(), array('langcode' => $langcode));
  }
  else {
    $size = $size / DRUPAL_KILOBYTE; // Convert bytes to kilobytes.
    $units = array(
      t('@size KB', array(), array('langcode' => $langcode)),
      t('@size MB', array(), array('langcode' => $langcode)),
      t('@size GB', array(), array('langcode' => $langcode)),
      t('@size TB', array(), array('langcode' => $langcode)),
      t('@size PB', array(), array('langcode' => $langcode)),
      t('@size EB', array(), array('langcode' => $langcode)),
      t('@size ZB', array(), array('langcode' => $langcode)),
      t('@size YB', array(), array('langcode' => $langcode)),
    );
    foreach ($units as $unit) {
      if (round($size, 2) >= DRUPAL_KILOBYTE) {
        $size = $size / DRUPAL_KILOBYTE;
      }
      else {
        break;
      }
    }
    return str_replace('@size', round($size, 2), $unit);
  }
}

/**
 * Formats a time interval with the requested granularity.
 *
 * @param $interval
 *   The length of the interval in seconds.
 * @param $granularity
 *   How many different units to display in the string.
 * @param $langcode
 *   Optional language code to translate to a language other than
 *   what is used to display the page.
 *
 * @return
 *   A translated string representation of the interval.
 */
function format_interval($interval, $granularity = 2, $langcode = NULL) {
  $units = array(
    '1 year|@count years' => 31536000,
    '1 month|@count months' => 2592000,
    '1 week|@count weeks' => 604800,
    '1 day|@count days' => 86400,
    '1 hour|@count hours' => 3600,
    '1 min|@count min' => 60,
    '1 sec|@count sec' => 1
  );
  $output = '';
  foreach ($units as $key => $value) {
    $key = explode('|', $key);
    if ($interval >= $value) {
      $output .= ($output ? ' ' : '') . format_plural(floor($interval / $value), $key[0], $key[1], array(), array('langcode' => $langcode));
      $interval %= $value;
      $granularity--;
    }

    if ($granularity == 0) {
      break;
    }
  }
  return $output ? $output : t('0 sec', array(), array('langcode' => $langcode));
}

/**
 * Formats a date, using a date type or a custom date format string.
 *
 * @param $timestamp
 *   A UNIX timestamp to format.
 * @param $type
 *   (optional) The format to use, one of:
 *   - 'short', 'medium', or 'long' (the corresponding built-in date formats).
 *   - The name of a date type defined by a module in hook_date_format_types(),
 *     if it's been assigned a format.
 *   - The machine name of an administrator-defined date format.
 *   - 'custom', to use $format.
 *   Defaults to 'medium'.
 * @param $format
 *   (optional) If $type is 'custom', a PHP date format string suitable for
 *   input to date(). Use a backslash to escape ordinary text, so it does not
 *   get interpreted as date format characters.
 * @param $timezone
 *   (optional) Time zone identifier, as described at
 *   http://php.net/manual/timezones.php Defaults to the time zone used to
 *   display the page.
 * @param $langcode
 *   (optional) Language code to translate to. Defaults to the language used to
 *   display the page.
 *
 * @return
 *   A translated date string in the requested format.
 */
function format_date($timestamp, $type = 'medium', $format = '', $timezone = NULL, $langcode = NULL) {
  // Use the advanced drupal_static() pattern, since this is called very often.
  static $drupal_static_fast;
  if (!isset($drupal_static_fast)) {
    $drupal_static_fast['timezones'] = &drupal_static(__FUNCTION__);
  }
  $timezones = &$drupal_static_fast['timezones'];

  if (!isset($timezone)) {
    $timezone = date_default_timezone_get();
  }
  // Store DateTimeZone objects in an array rather than repeatedly
  // constructing identical objects over the life of a request.
  if (!isset($timezones[$timezone])) {
    $timezones[$timezone] = timezone_open($timezone);
  }

  // Use the default langcode if none is set.
  global $language;
  if (empty($langcode)) {
    $langcode = isset($language->language) ? $language->language : 'en';
  }

  switch ($type) {
    case 'short':
      $format = variable_get('date_format_short', 'm/d/Y - H:i');
      break;

    case 'long':
      $format = variable_get('date_format_long', 'l, F j, Y - H:i');
      break;

    case 'custom':
      // No change to format.
      break;

    case 'medium':
    default:
      // Retrieve the format of the custom $type passed.
      if ($type != 'medium') {
        $format = variable_get('date_format_' . $type, '');
      }
      // Fall back to 'medium'.
      if ($format === '') {
        $format = variable_get('date_format_medium', 'D, m/d/Y - H:i');
      }
      break;
  }

  // Create a DateTime object from the timestamp.
  $date_time = date_create('@' . $timestamp);
  // Set the time zone for the DateTime object.
  date_timezone_set($date_time, $timezones[$timezone]);

  // Encode markers that should be translated. 'A' becomes '\xEF\AA\xFF'.
  // xEF and xFF are invalid UTF-8 sequences, and we assume they are not in the
  // input string.
  // Paired backslashes are isolated to prevent errors in read-ahead evaluation.
  // The read-ahead expression ensures that A matches, but not \A.
  $format = preg_replace(array('/\\\\\\\\/', '/(?<!\\\\)([AaeDlMTF])/'), array("\xEF\\\\\\\\\xFF", "\xEF\\\\\$1\$1\xFF"), $format);

  // Call date_format().
  $format = date_format($date_time, $format);

  // Pass the langcode to _format_date_callback().
  _format_date_callback(NULL, $langcode);

  // Translate the marked sequences.
  return preg_replace_callback('/\xEF([AaeDlMTF]?)(.*?)\xFF/', '_format_date_callback', $format);
}

/**
 * Returns an ISO8601 formatted date based on the given date.
 *
 * Callback for use within hook_rdf_mapping() implementations.
 *
 * @param $date
 *   A UNIX timestamp.
 *
 * @return string
 *   An ISO8601 formatted date.
 */
function date_iso8601($date) {
  // The DATE_ISO8601 constant cannot be used here because it does not match
  // date('c') and produces invalid RDF markup.
  return date('c', $date);
}

/**
 * Translates a formatted date string.
 *
 * Callback for preg_replace_callback() within format_date().
 */
function _format_date_callback(array $matches = NULL, $new_langcode = NULL) {
  // We cache translations to avoid redundant and rather costly calls to t().
  static $cache, $langcode;

  if (!isset($matches)) {
    $langcode = $new_langcode;
    return;
  }

  $code = $matches[1];
  $string = $matches[2];

  if (!isset($cache[$langcode][$code][$string])) {
    $options = array(
      'langcode' => $langcode,
    );

    if ($code == 'F') {
      $options['context'] = 'Long month name';
    }

    if ($code == '') {
      $cache[$langcode][$code][$string] = $string;
    }
    else {
      $cache[$langcode][$code][$string] = t($string, array(), $options);
    }
  }
  return $cache[$langcode][$code][$string];
}

/**
 * Format a username.
 *
 * This is also the label callback implementation of
 * callback_entity_info_label() for user_entity_info().
 *
 * By default, the passed-in object's 'name' property is used if it exists, or
 * else, the site-defined value for the 'anonymous' variable. However, a module
 * may override this by implementing hook_username_alter(&$name, $account).
 *
 * @see hook_username_alter()
 *
 * @param $account
 *   The account object for the user whose name is to be formatted.
 *
 * @return
 *   An unsanitized string with the username to display. The code receiving
 *   this result must ensure that check_plain() is called on it before it is
 *   printed to the page.
 */
function format_username($account) {
  $name = !empty($account->name) ? $account->name : variable_get('anonymous', t('Anonymous'));
  drupal_alter('username', $name, $account);
  return $name;
}

/**
 * @} End of "defgroup format".
 */

/**
 * Generates an internal or external URL.
 *
 * When creating links in modules, consider whether l() could be a better
 * alternative than url().
 *
 * @param $path
 *   (optional) The internal path or external URL being linked to, such as
 *   "node/34" or "http://example.com/foo". The default value is equivalent to
 *   passing in '<front>'. A few notes:
 *   - If you provide a full URL, it will be considered an external URL.
 *   - If you provide only the path (e.g. "node/34"), it will be
 *     considered an internal link. In this case, it should be a system URL,
 *     and it will be replaced with the alias, if one exists. Additional query
 *     arguments for internal paths must be supplied in $options['query'], not
 *     included in $path.
 *   - If you provide an internal path and $options['alias'] is set to TRUE, the
 *     path is assumed already to be the correct path alias, and the alias is
 *     not looked up.
 *   - The special string '<front>' generates a link to the site's base URL.
 *   - If your external URL contains a query (e.g. http://example.com/foo?a=b),
 *     then you can either URL encode the query keys and values yourself and
 *     include them in $path, or use $options['query'] to let this function
 *     URL encode them.
 * @param $options
 *   (optional) An associative array of additional options, with the following
 *   elements:
 *   - 'query': An array of query key/value-pairs (without any URL-encoding) to
 *     append to the URL.
 *   - 'fragment': A fragment identifier (named anchor) to append to the URL.
 *     Do not include the leading '#' character.
 *   - 'absolute': Defaults to FALSE. Whether to force the output to be an
 *     absolute link (beginning with http:). Useful for links that will be
 *     displayed outside the site, such as in an RSS feed.
 *   - 'alias': Defaults to FALSE. Whether the given path is a URL alias
 *     already.
 *   - 'external': Whether the given path is an external URL.
 *   - 'language': An optional language object. If the path being linked to is
 *     internal to the site, $options['language'] is used to look up the alias
 *     for the URL. If $options['language'] is omitted, the global $language_url
 *     will be used.
 *   - 'https': Whether this URL should point to a secure location. If not
 *     defined, the current scheme is used, so the user stays on HTTP or HTTPS
 *     respectively. TRUE enforces HTTPS and FALSE enforces HTTP, but HTTPS can
 *     only be enforced when the variable 'https' is set to TRUE.
 *   - 'base_url': Only used internally, to modify the base URL when a language
 *     dependent URL requires so.
 *   - 'prefix': Only used internally, to modify the path when a language
 *     dependent URL requires so.
 *   - 'script': The script filename in Drupal's root directory to use when
 *     clean URLs are disabled, such as 'index.php'. Defaults to an empty
 *     string, as most modern web servers automatically find 'index.php'. If
 *     clean URLs are disabled, the value of $path is appended as query
 *     parameter 'q' to $options['script'] in the returned URL. When deploying
 *     Drupal on a web server that cannot be configured to automatically find
 *     index.php, then hook_url_outbound_alter() can be implemented to force
 *     this value to 'index.php'.
 *   - 'entity_type': The entity type of the object that called url(). Only
 *     set if url() is invoked by entity_uri().
 *   - 'entity': The entity object (such as a node) for which the URL is being
 *     generated. Only set if url() is invoked by entity_uri().
 *
 * @return
 *   A string containing a URL to the given path.
 */
function url($path = NULL, array $options = array()) {
  // Merge in defaults.
  $options += array(
    'fragment' => '',
    'query' => array(),
    'absolute' => FALSE,
    'alias' => FALSE,
    'prefix' => ''
  );

  // A duplicate of the code from url_is_external() to avoid needing another
  // function call, since performance inside url() is critical.
  if (!isset($options['external'])) {
    // Return an external link if $path contains an allowed absolute URL. Avoid
    // calling drupal_strip_dangerous_protocols() if there is any slash (/),
    // hash (#) or question_mark (?) before the colon (:) occurrence - if any -
    // as this would clearly mean it is not a URL. If the path starts with 2
    // slashes then it is always considered an external URL without an explicit
    // protocol part.
    $colonpos = strpos($path, ':');
    $options['external'] = (strpos($path, '//') === 0)
      || ($colonpos !== FALSE
        && !preg_match('![/?#]!', substr($path, 0, $colonpos))
        && drupal_strip_dangerous_protocols($path) == $path);
  }

  // Preserve the original path before altering or aliasing.
  $original_path = $path;

  // Allow other modules to alter the outbound URL and options.
  drupal_alter('url_outbound', $path, $options, $original_path);

  if (isset($options['fragment']) && $options['fragment'] !== '') {
    $options['fragment'] = '#' . $options['fragment'];
  }

  if ($options['external']) {
    // Split off the fragment.
    if (strpos($path, '#') !== FALSE) {
      list($path, $old_fragment) = explode('#', $path, 2);
      // If $options contains no fragment, take it over from the path.
      if (isset($old_fragment) && !$options['fragment']) {
        $options['fragment'] = '#' . $old_fragment;
      }
    }
    // Append the query.
    if ($options['query']) {
      $path .= (strpos($path, '?') !== FALSE ? '&' : '?') . drupal_http_build_query($options['query']);
    }
    if (isset($options['https']) && variable_get('https', FALSE)) {
      if ($options['https'] === TRUE) {
        $path = str_replace('http://', 'https://', $path);
      }
      elseif ($options['https'] === FALSE) {
        $path = str_replace('https://', 'http://', $path);
      }
    }
    // Reassemble.
    return $path . $options['fragment'];
  }

  // Strip leading slashes from internal paths to prevent them becoming external
  // URLs without protocol. /example.com should not be turned into
  // //example.com.
  $path = ltrim($path, '/');

  global $base_url, $base_secure_url, $base_insecure_url;

  // The base_url might be rewritten from the language rewrite in domain mode.
  if (!isset($options['base_url'])) {
    if (isset($options['https']) && variable_get('https', FALSE)) {
      if ($options['https'] === TRUE) {
        $options['base_url'] = $base_secure_url;
        $options['absolute'] = TRUE;
      }
      elseif ($options['https'] === FALSE) {
        $options['base_url'] = $base_insecure_url;
        $options['absolute'] = TRUE;
      }
    }
    else {
      $options['base_url'] = $base_url;
    }
  }

  // The special path '<front>' links to the default front page.
  if ($path == '<front>') {
    $path = '';
  }
  elseif (!empty($path) && !$options['alias']) {
    $language = isset($options['language']) && isset($options['language']->language) ? $options['language']->language : '';
    $alias = drupal_get_path_alias($original_path, $language);
    if ($alias != $original_path) {
      $path = $alias;
    }
  }

  $base = $options['absolute'] ? $options['base_url'] . '/' : base_path();
  $prefix = empty($path) ? rtrim($options['prefix'], '/') : $options['prefix'];

  // With Clean URLs.
  if (!empty($GLOBALS['conf']['clean_url'])) {
    $path = drupal_encode_path($prefix . $path);
    if ($options['query']) {
      return $base . $path . '?' . drupal_http_build_query($options['query']) . $options['fragment'];
    }
    else {
      return $base . $path . $options['fragment'];
    }
  }
  // Without Clean URLs.
  else {
    $path = $prefix . $path;
    $query = array();
    if (!empty($path)) {
      $query['q'] = $path;
    }
    if ($options['query']) {
      // We do not use array_merge() here to prevent overriding $path via query
      // parameters.
      $query += $options['query'];
    }
    $query = $query ? ('?' . drupal_http_build_query($query)) : '';
    $script = isset($options['script']) ? $options['script'] : '';
    return $base . $script . $query . $options['fragment'];
  }
}

/**
 * Returns TRUE if a path is external to Drupal (e.g. http://example.com).
 *
 * If a path cannot be assessed by Drupal's menu handler, then we must
 * treat it as potentially insecure.
 *
 * @param $path
 *   The internal path or external URL being linked to, such as "node/34" or
 *   "http://example.com/foo".
 *
 * @return
 *   Boolean TRUE or FALSE, where TRUE indicates an external path.
 */
function url_is_external($path) {
  $colonpos = strpos($path, ':');
  // Avoid calling drupal_strip_dangerous_protocols() if there is any slash (/),
  // hash (#) or question_mark (?) before the colon (:) occurrence - if any - as
  // this would clearly mean it is not a URL. If the path starts with 2 slashes
  // then it is always considered an external URL without an explicit protocol
  // part.
  return (strpos($path, '//') === 0)
    || ($colonpos !== FALSE
      && !preg_match('![/?#]!', substr($path, 0, $colonpos))
      && drupal_strip_dangerous_protocols($path) == $path);
}

/**
 * Formats an attribute string for an HTTP header.
 *
 * @param $attributes
 *   An associative array of attributes such as 'rel'.
 *
 * @return
 *   A ; separated string ready for insertion in a HTTP header. No escaping is
 *   performed for HTML entities, so this string is not safe to be printed.
 *
 * @see drupal_add_http_header()
 */
function drupal_http_header_attributes(array $attributes = array()) {
  foreach ($attributes as $attribute => &$data) {
    if (is_array($data)) {
      $data = implode(' ', $data);
    }
    $data = $attribute . '="' . $data . '"';
  }
  return $attributes ? ' ' . implode('; ', $attributes) : '';
}

/**
 * Converts an associative array to an XML/HTML tag attribute string.
 *
 * Each array key and its value will be formatted into an attribute string.
 * If a value is itself an array, then its elements are concatenated to a single
 * space-delimited string (for example, a class attribute with multiple values).
 *
 * Attribute values are sanitized by running them through check_plain().
 * Attribute names are not automatically sanitized. When using user-supplied
 * attribute names, it is strongly recommended to allow only white-listed names,
 * since certain attributes carry security risks and can be abused.
 *
 * Examples of security aspects when using drupal_attributes:
 * @code
 *   // By running the value in the following statement through check_plain,
 *   // the malicious script is neutralized.
 *   drupal_attributes(array('title' => t('<script>steal_cookie();</script>')));
 *
 *   // The statement below demonstrates dangerous use of drupal_attributes, and
 *   // will return an onmouseout attribute with JavaScript code that, when used
 *   // as attribute in a tag, will cause users to be redirected to another site.
 *   //
 *   // In this case, the 'onmouseout' attribute should not be whitelisted --
 *   // you don't want users to have the ability to add this attribute or others
 *   // that take JavaScript commands.
 *   drupal_attributes(array('onmouseout' => 'window.location="http://malicious.com/";')));
 * @endcode
 *
 * @param $attributes
 *   An associative array of key-value pairs to be converted to attributes.
 *
 * @return
 *   A string ready for insertion in a tag (starts with a space).
 *
 * @ingroup sanitization
 */
function drupal_attributes(array $attributes = array()) {
  foreach ($attributes as $attribute => &$data) {
    $data = implode(' ', (array) $data);
    $data = $attribute . '="' . check_plain($data) . '"';
  }
  return $attributes ? ' ' . implode(' ', $attributes) : '';
}

/**
 * Formats an internal or external URL link as an HTML anchor tag.
 *
 * This function correctly handles aliased paths and adds an 'active' class
 * attribute to links that point to the current page (for theming), so all
 * internal links output by modules should be generated by this function if
 * possible.
 *
 * However, for links enclosed in translatable text you should use t() and
 * embed the HTML anchor tag directly in the translated string. For example:
 * @code
 * t('Visit the <a href="@url">settings</a> page', array('@url' => url('admin')));
 * @endcode
 * This keeps the context of the link title ('settings' in the example) for
 * translators.
 *
 * @param string $text
 *   The translated link text for the anchor tag.
 * @param string $path
 *   The internal path or external URL being linked to, such as "node/34" or
 *   "http://example.com/foo". After the url() function is called to construct
 *   the URL from $path and $options, the resulting URL is passed through
 *   check_plain() before it is inserted into the HTML anchor tag, to ensure
 *   well-formed HTML. See url() for more information and notes.
 * @param array $options
 *   An associative array of additional options. Defaults to an empty array. It
 *   may contain the following elements.
 *   - 'attributes': An associative array of HTML attributes to apply to the
 *     anchor tag. If element 'class' is included, it must be an array; 'title'
 *     must be a string; other elements are more flexible, as they just need
 *     to work in a call to drupal_attributes($options['attributes']).
 *   - 'html' (default FALSE): Whether $text is HTML or just plain-text. For
 *     example, to make an image tag into a link, this must be set to TRUE, or
 *     you will see the escaped HTML image tag. $text is not sanitized if
 *     'html' is TRUE. The calling function must ensure that $text is already
 *     safe.
 *   - 'language': An optional language object. If the path being linked to is
 *     internal to the site, $options['language'] is used to determine whether
 *     the link is "active", or pointing to the current page (the language as
 *     well as the path must match). This element is also used by url().
 *   - Additional $options elements used by the url() function.
 *
 * @return string
 *   An HTML string containing a link to the given path.
 *
 * @see url()
 */
function l($text, $path, array $options = array()) {
  global $language_url;
  static $use_theme = NULL;

  // Merge in defaults.
  $options += array(
    'attributes' => array(),
    'html' => FALSE,
  );

  // Append active class.
  if (($path == $_GET['q'] || ($path == '<front>' && drupal_is_front_page())) &&
      (empty($options['language']) || $options['language']->language == $language_url->language)) {
    $options['attributes']['class'][] = 'active';
  }

  // Remove all HTML and PHP tags from a tooltip. For best performance, we act only
  // if a quick strpos() pre-check gave a suspicion (because strip_tags() is expensive).
  if (isset($options['attributes']['title']) && strpos($options['attributes']['title'], '<') !== FALSE) {
    $options['attributes']['title'] = strip_tags($options['attributes']['title']);
  }

  // Determine if rendering of the link is to be done with a theme function
  // or the inline default. Inline is faster, but if the theme system has been
  // loaded and a module or theme implements a preprocess or process function
  // or overrides the theme_link() function, then invoke theme(). Preliminary
  // benchmarks indicate that invoking theme() can slow down the l() function
  // by 20% or more, and that some of the link-heavy Drupal pages spend more
  // than 10% of the total page request time in the l() function.
  if (!isset($use_theme) && function_exists('theme')) {
    // Allow edge cases to prevent theme initialization and force inline link
    // rendering.
    if (variable_get('theme_link', TRUE)) {
      drupal_theme_initialize();
      $registry = theme_get_registry(FALSE);
      // We don't want to duplicate functionality that's in theme(), so any
      // hint of a module or theme doing anything at all special with the 'link'
      // theme hook should simply result in theme() being called. This includes
      // the overriding of theme_link() with an alternate function or template,
      // the presence of preprocess or process functions, or the presence of
      // include files.
      $use_theme = !isset($registry['link']['function']) || ($registry['link']['function'] != 'theme_link');
      $use_theme = $use_theme || !empty($registry['link']['preprocess functions']) || !empty($registry['link']['process functions']) || !empty($registry['link']['includes']);
    }
    else {
      $use_theme = FALSE;
    }
  }
  if ($use_theme) {
    return theme('link', array('text' => $text, 'path' => $path, 'options' => $options));
  }
  // The result of url() is a plain-text URL. Because we are using it here
  // in an HTML argument context, we need to encode it properly.
  return '<a href="' . check_plain(url($path, $options)) . '"' . drupal_attributes($options['attributes']) . '>' . ($options['html'] ? $text : check_plain($text)) . '</a>';
}

/**
 * Delivers a page callback result to the browser in the appropriate format.
 *
 * This function is most commonly called by menu_execute_active_handler(), but
 * can also be called by error conditions such as drupal_not_found(),
 * drupal_access_denied(), and drupal_site_offline().
 *
 * When a user requests a page, index.php calls menu_execute_active_handler(),
 * which calls the 'page callback' function registered in hook_menu(). The page
 * callback function can return one of:
 * - NULL: to indicate no content.
 * - An integer menu status constant: to indicate an error condition.
 * - A string of HTML content.
 * - A renderable array of content.
 * Returning a renderable array rather than a string of HTML is preferred,
 * because that provides modules with more flexibility in customizing the final
 * result.
 *
 * When the page callback returns its constructed content to
 * menu_execute_active_handler(), this function gets called. The purpose of
 * this function is to determine the most appropriate 'delivery callback'
 * function to route the content to. The delivery callback function then
 * sends the content to the browser in the needed format. The default delivery
 * callback is drupal_deliver_html_page(), which delivers the content as an HTML
 * page, complete with blocks in addition to the content. This default can be
 * overridden on a per menu router item basis by setting 'delivery callback' in
 * hook_menu() or hook_menu_alter(), and can also be overridden on a per request
 * basis in hook_page_delivery_callback_alter().
 *
 * For example, the same page callback function can be used for an HTML
 * version of the page and an Ajax version of the page. The page callback
 * function just needs to decide what content is to be returned and the
 * delivery callback function will send it as an HTML page or an Ajax
 * response, as appropriate.
 *
 * In order for page callbacks to be reusable in different delivery formats,
 * they should not issue any "print" or "echo" statements, but instead just
 * return content.
 *
 * Also note that this function does not perform access checks. The delivery
 * callback function specified in hook_menu(), hook_menu_alter(), or
 * hook_page_delivery_callback_alter() will be called even if the router item
 * access checks fail. This is intentional (it is needed for JSON and other
 * purposes), but it has security implications. Do not call this function
 * directly unless you understand the security implications, and be careful in
 * writing delivery callbacks, so that they do not violate security. See
 * drupal_deliver_html_page() for an example of a delivery callback that
 * respects security.
 *
 * @param $page_callback_result
 *   The result of a page callback. Can be one of:
 *   - NULL: to indicate no content.
 *   - An integer menu status constant: to indicate an error condition.
 *   - A string of HTML content.
 *   - A renderable array of content.
 * @param $default_delivery_callback
 *   (Optional) If given, it is the name of a delivery function most likely
 *   to be appropriate for the page request as determined by the calling
 *   function (e.g., menu_execute_active_handler()). If not given, it is
 *   determined from the menu router information of the current page.
 *
 * @see menu_execute_active_handler()
 * @see hook_menu()
 * @see hook_menu_alter()
 * @see hook_page_delivery_callback_alter()
 */
function drupal_deliver_page($page_callback_result, $default_delivery_callback = NULL) {
  if (!isset($default_delivery_callback) && ($router_item = menu_get_item())) {
    $default_delivery_callback = $router_item['delivery_callback'];
  }
  $delivery_callback = !empty($default_delivery_callback) ? $default_delivery_callback : 'drupal_deliver_html_page';
  // Give modules a chance to alter the delivery callback used, based on
  // request-time context (e.g., HTTP request headers).
  drupal_alter('page_delivery_callback', $delivery_callback);
  if (function_exists($delivery_callback)) {
    $delivery_callback($page_callback_result);
  }
  else {
    // If a delivery callback is specified, but doesn't exist as a function,
    // something is wrong, but don't print anything, since it's not known
    // what format the response needs to be in.
    watchdog('delivery callback not found', 'callback %callback not found: %q.', array('%callback' => $delivery_callback, '%q' => $_GET['q']), WATCHDOG_ERROR);
  }
}

/**
 * Packages and sends the result of a page callback to the browser as HTML.
 *
 * @param $page_callback_result
 *   The result of a page callback. Can be one of:
 *   - NULL: to indicate no content.
 *   - An integer menu status constant: to indicate an error condition.
 *   - A string of HTML content.
 *   - A renderable array of content.
 *
 * @see drupal_deliver_page()
 */
function drupal_deliver_html_page($page_callback_result) {
  // Emit the correct charset HTTP header, but not if the page callback
  // result is NULL, since that likely indicates that it printed something
  // in which case, no further headers may be sent, and not if code running
  // for this page request has already set the content type header.
  if (isset($page_callback_result) && is_null(drupal_get_http_header('Content-Type'))) {
    drupal_add_http_header('Content-Type', 'text/html; charset=utf-8');
  }

  // Send appropriate HTTP-Header for browsers and search engines.
  global $language;
  drupal_add_http_header('Content-Language', $language->language);

  // Menu status constants are integers; page content is a string or array.
  if (is_int($page_callback_result)) {
    // @todo: Break these up into separate functions?
    switch ($page_callback_result) {
      case MENU_NOT_FOUND:
        // Print a 404 page.
        drupal_add_http_header('Status', '404 Not Found');

        watchdog('page not found', check_plain($_GET['q']), NULL, WATCHDOG_WARNING);

        // Check for and return a fast 404 page if configured.
        drupal_fast_404();

        // Keep old path for reference, and to allow forms to redirect to it.
        if (!isset($_GET['destination'])) {
          // Make sure that the current path is not interpreted as external URL.
          if (!url_is_external($_GET['q'])) {
            $_GET['destination'] = $_GET['q'];
          }
        }

        $path = drupal_get_normal_path(variable_get('site_404', ''));
        if ($path && $path != $_GET['q']) {
          // Custom 404 handler. Set the active item in case there are tabs to
          // display, or other dependencies on the path.
          menu_set_active_item($path);
          $return = menu_execute_active_handler($path, FALSE);
        }

        if (empty($return) || $return == MENU_NOT_FOUND || $return == MENU_ACCESS_DENIED) {
          // Standard 404 handler.
          drupal_set_title(t('Page not found'));
          $return = t('The requested page "@path" could not be found.', array('@path' => request_uri()));
        }

        drupal_set_page_content($return);
        $page = element_info('page');
        print drupal_render_page($page);
        break;

      case MENU_ACCESS_DENIED:
        // Print a 403 page.
        drupal_add_http_header('Status', '403 Forbidden');
        watchdog('access denied', check_plain($_GET['q']), NULL, WATCHDOG_WARNING);

        // Keep old path for reference, and to allow forms to redirect to it.
        if (!isset($_GET['destination'])) {
          // Make sure that the current path is not interpreted as external URL.
          if (!url_is_external($_GET['q'])) {
            $_GET['destination'] = $_GET['q'];
          }
        }

        $path = drupal_get_normal_path(variable_get('site_403', ''));
        if ($path && $path != $_GET['q']) {
          // Custom 403 handler. Set the active item in case there are tabs to
          // display or other dependencies on the path.
          menu_set_active_item($path);
          $return = menu_execute_active_handler($path, FALSE);
        }

        if (empty($return) || $return == MENU_NOT_FOUND || $return == MENU_ACCESS_DENIED) {
          // Standard 403 handler.
          drupal_set_title(t('Access denied'));
          $return = t('You are not authorized to access this page.');
        }

        print drupal_render_page($return);
        break;

      case MENU_SITE_OFFLINE:
        // Print a 503 page.
        drupal_maintenance_theme();
        drupal_add_http_header('Status', '503 Service unavailable');
        drupal_set_title(t('Site under maintenance'));
        print theme('maintenance_page', array('content' => filter_xss_admin(variable_get('maintenance_mode_message',
          t('@site is currently under maintenance. We should be back shortly. Thank you for your patience.', array('@site' => variable_get('site_name', 'Drupal')))))));
        break;
    }
  }
  elseif (isset($page_callback_result)) {
    // Print anything besides a menu constant, assuming it's not NULL or
    // undefined.
    print drupal_render_page($page_callback_result);
  }

  // Perform end-of-request tasks.
  drupal_page_footer();
}

/**
 * Performs end-of-request tasks.
 *
 * This function sets the page cache if appropriate, and allows modules to
 * react to the closing of the page by calling hook_exit().
 */
function drupal_page_footer() {
  global $user;

  module_invoke_all('exit');

  // Commit the user session, if needed.
  drupal_session_commit();

  if (variable_get('cache', 0) && ($cache = drupal_page_set_cache())) {
    drupal_serve_page_from_cache($cache);
  }
  else {
    ob_flush();
  }

  _registry_check_code(REGISTRY_WRITE_LOOKUP_CACHE);
  drupal_cache_system_paths();
  module_implements_write_cache();
  system_run_automated_cron();
}

/**
 * Performs end-of-request tasks.
 *
 * In some cases page requests need to end without calling drupal_page_footer().
 * In these cases, call drupal_exit() instead. There should rarely be a reason
 * to call exit instead of drupal_exit();
 *
 * @param $destination
 *   If this function is called from drupal_goto(), then this argument
 *   will be a fully-qualified URL that is the destination of the redirect.
 *   This should be passed along to hook_exit() implementations.
 */
function drupal_exit($destination = NULL) {
  if (drupal_get_bootstrap_phase() == DRUPAL_BOOTSTRAP_FULL) {
    if (!defined('MAINTENANCE_MODE') || MAINTENANCE_MODE != 'update') {
      module_invoke_all('exit', $destination);
    }
    drupal_session_commit();
  }
  exit;
}

/**
 * Forms an associative array from a linear array.
 *
 * This function walks through the provided array and constructs an associative
 * array out of it. The keys of the resulting array will be the values of the
 * input array. The values will be the same as the keys unless a function is
 * specified, in which case the output of the function is used for the values
 * instead.
 *
 * @param $array
 *   A linear array.
 * @param $function
 *   A name of a function to apply to all values before output.
 *
 * @return
 *   An associative array.
 */
function drupal_map_assoc($array, $function = NULL) {
  // array_combine() fails with empty arrays:
  // http://bugs.php.net/bug.php?id=34857.
  $array = !empty($array) ? array_combine($array, $array) : array();
  if (is_callable($function)) {
    $array = array_map($function, $array);
  }
  return $array;
}

/**
 * Attempts to set the PHP maximum execution time.
 *
 * This function is a wrapper around the PHP function set_time_limit().
 * When called, set_time_limit() restarts the timeout counter from zero.
 * In other words, if the timeout is the default 30 seconds, and 25 seconds
 * into script execution a call such as set_time_limit(20) is made, the
 * script will run for a total of 45 seconds before timing out.
 *
 * It also means that it is possible to decrease the total time limit if
 * the sum of the new time limit and the current time spent running the
 * script is inferior to the original time limit. It is inherent to the way
 * set_time_limit() works, it should rather be called with an appropriate
 * value every time you need to allocate a certain amount of time
 * to execute a task than only once at the beginning of the script.
 *
 * Before calling set_time_limit(), we check if this function is available
 * because it could be disabled by the server administrator. We also hide all
 * the errors that could occur when calling set_time_limit(), because it is
 * not possible to reliably ensure that PHP or a security extension will
 * not issue a warning/error if they prevent the use of this function.
 *
 * @param $time_limit
 *   An integer specifying the new time limit, in seconds. A value of 0
 *   indicates unlimited execution time.
 *
 * @ingroup php_wrappers
 */
function drupal_set_time_limit($time_limit) {
  if (function_exists('set_time_limit')) {
    @set_time_limit($time_limit);
  }
}

/**
 * Returns the path to a system item (module, theme, etc.).
 *
 * @param $type
 *   The type of the item (i.e. theme, theme_engine, module, profile).
 * @param $name
 *   The name of the item for which the path is requested.
 *
 * @return
 *   The path to the requested item or an empty string if the item is not found.
 */
function drupal_get_path($type, $name) {
  return dirname(drupal_get_filename($type, $name));
}

/**
 * Returns the base URL path (i.e., directory) of the Drupal installation.
 *
 * base_path() adds a "/" to the beginning and end of the returned path if the
 * path is not empty. At the very least, this will return "/".
 *
 * Examples:
 * - http://example.com returns "/" because the path is empty.
 * - http://example.com/drupal/folder returns "/drupal/folder/".
 */
function base_path() {
  return $GLOBALS['base_path'];
}

/**
 * Adds a LINK tag with a distinct 'rel' attribute to the page's HEAD.
 *
 * This function can be called as long the HTML header hasn't been sent, which
 * on normal pages is up through the preprocess step of theme('html'). Adding
 * a link will overwrite a prior link with the exact same 'rel' and 'href'
 * attributes.
 *
 * @param $attributes
 *   Associative array of element attributes including 'href' and 'rel'.
 * @param $header
 *   Optional flag to determine if a HTTP 'Link:' header should be sent.
 */
function drupal_add_html_head_link($attributes, $header = FALSE) {
  $element = array(
    '#tag' => 'link',
    '#attributes' => $attributes,
  );
  $href = $attributes['href'];

  if ($header) {
    // Also add a HTTP header "Link:".
    $href = '<' . check_plain($attributes['href']) . '>;';
    unset($attributes['href']);
    $element['#attached']['drupal_add_http_header'][] = array('Link',  $href . drupal_http_header_attributes($attributes), TRUE);
  }

  drupal_add_html_head($element, 'drupal_add_html_head_link:' . $attributes['rel'] . ':' . $href);
}

/**
 * Adds a cascading stylesheet to the stylesheet queue.
 *
 * Calling drupal_static_reset('drupal_add_css') will clear all cascading
 * stylesheets added so far.
 *
 * If CSS aggregation/compression is enabled, all cascading style sheets added
 * with $options['preprocess'] set to TRUE will be merged into one aggregate
 * file and compressed by removing all extraneous white space.
 * Preprocessed inline stylesheets will not be aggregated into this single file;
 * instead, they are just compressed upon output on the page. Externally hosted
 * stylesheets are never aggregated or compressed.
 *
 * The reason for aggregating the files is outlined quite thoroughly here:
 * http://www.die.net/musings/page_load_time/ "Load fewer external objects. Due
 * to request overhead, one bigger file just loads faster than two smaller ones
 * half its size."
 *
 * $options['preprocess'] should be only set to TRUE when a file is required for
 * all typical visitors and most pages of a site. It is critical that all
 * preprocessed files are added unconditionally on every page, even if the
 * files do not happen to be needed on a page. This is normally done by calling
 * drupal_add_css() in a hook_init() implementation.
 *
 * Non-preprocessed files should only be added to the page when they are
 * actually needed.
 *
 * @param $data
 *   (optional) The stylesheet data to be added, depending on what is passed
 *   through to the $options['type'] parameter:
 *   - 'file': The path to the CSS file relative to the base_path(), or a
 *     stream wrapper URI. For example: "modules/devel/devel.css" or
 *     "public://generated_css/stylesheet_1.css". Note that Modules should
 *     always prefix the names of their CSS files with the module name; for
 *     example, system-menus.css rather than simply menus.css. Themes can
 *     override module-supplied CSS files based on their filenames, and this
 *     prefixing helps prevent confusing name collisions for theme developers.
 *     See drupal_get_css() where the overrides are performed. Also, if the
 *     direction of the current language is right-to-left (Hebrew, Arabic,
 *     etc.), the function will also look for an RTL CSS file and append it to
 *     the list. The name of this file should have an '-rtl.css' suffix. For
 *     example, a CSS file called 'mymodule-name.css' will have a
 *     'mymodule-name-rtl.css' file added to the list, if exists in the same
 *     directory. This CSS file should contain overrides for properties which
 *     should be reversed or otherwise different in a right-to-left display.
 *   - 'inline': A string of CSS that should be placed in the given scope. Note
 *     that it is better practice to use 'file' stylesheets, rather than
 *     'inline', as the CSS would then be aggregated and cached.
 *   - 'external': The absolute path to an external CSS file that is not hosted
 *     on the local server. These files will not be aggregated if CSS
 *     aggregation is enabled.
 * @param $options
 *   (optional) A string defining the 'type' of CSS that is being added in the
 *   $data parameter ('file', 'inline', or 'external'), or an array which can
 *   have any or all of the following keys:
 *   - 'type': The type of stylesheet being added. Available options are 'file',
 *     'inline' or 'external'. Defaults to 'file'.
 *   - 'basename': Force a basename for the file being added. Modules are
 *     expected to use stylesheets with unique filenames, but integration of
 *     external libraries may make this impossible. The basename of
 *     'modules/node/node.css' is 'node.css'. If the external library "node.js"
 *     ships with a 'node.css', then a different, unique basename would be
 *     'node.js.css'.
 *   - 'group': A number identifying the group in which to add the stylesheet.
 *     Available constants are:
 *     - CSS_SYSTEM: Any system-layer CSS.
 *     - CSS_DEFAULT: (default) Any module-layer CSS.
 *     - CSS_THEME: Any theme-layer CSS.
 *     The group number serves as a weight: the markup for loading a stylesheet
 *     within a lower weight group is output to the page before the markup for
 *     loading a stylesheet within a higher weight group, so CSS within higher
 *     weight groups take precendence over CSS within lower weight groups.
 *   - 'every_page': For optimal front-end performance when aggregation is
 *     enabled, this should be set to TRUE if the stylesheet is present on every
 *     page of the website for users for whom it is present at all. This
 *     defaults to FALSE. It is set to TRUE for stylesheets added via module and
 *     theme .info files. Modules that add stylesheets within hook_init()
 *     implementations, or from other code that ensures that the stylesheet is
 *     added to all website pages, should also set this flag to TRUE. All
 *     stylesheets within the same group that have the 'every_page' flag set to
 *     TRUE and do not have 'preprocess' set to FALSE are aggregated together
 *     into a single aggregate file, and that aggregate file can be reused
 *     across a user's entire site visit, leading to faster navigation between
 *     pages. However, stylesheets that are only needed on pages less frequently
 *     visited, can be added by code that only runs for those particular pages,
 *     and that code should not set the 'every_page' flag. This minimizes the
 *     size of the aggregate file that the user needs to download when first
 *     visiting the website. Stylesheets without the 'every_page' flag are
 *     aggregated into a separate aggregate file. This other aggregate file is
 *     likely to change from page to page, and each new aggregate file needs to
 *     be downloaded when first encountered, so it should be kept relatively
 *     small by ensuring that most commonly needed stylesheets are added to
 *     every page.
 *   - 'weight': The weight of the stylesheet specifies the order in which the
 *     CSS will appear relative to other stylesheets with the same group and
 *     'every_page' flag. The exact ordering of stylesheets is as follows:
 *     - First by group.
 *     - Then by the 'every_page' flag, with TRUE coming before FALSE.
 *     - Then by weight.
 *     - Then by the order in which the CSS was added. For example, all else
 *       being the same, a stylesheet added by a call to drupal_add_css() that
 *       happened later in the page request gets added to the page after one for
 *       which drupal_add_css() happened earlier in the page request.
 *   - 'media': The media type for the stylesheet, e.g., all, print, screen.
 *     Defaults to 'all'.
 *   - 'preprocess': If TRUE and CSS aggregation/compression is enabled, the
 *     styles will be aggregated and compressed. Defaults to TRUE.
 *   - 'browsers': An array containing information specifying which browsers
 *     should load the CSS item. See drupal_pre_render_conditional_comments()
 *     for details.
 *
 * @return
 *   An array of queued cascading stylesheets.
 *
 * @see drupal_get_css()
 */
function drupal_add_css($data = NULL, $options = NULL) {
  $css = &drupal_static(__FUNCTION__, array());

  // Construct the options, taking the defaults into consideration.
  if (isset($options)) {
    if (!is_array($options)) {
      $options = array('type' => $options);
    }
  }
  else {
    $options = array();
  }

  // Create an array of CSS files for each media type first, since each type needs to be served
  // to the browser differently.
  if (isset($data)) {
    $options += array(
      'type' => 'file',
      'group' => CSS_DEFAULT,
      'weight' => 0,
      'every_page' => FALSE,
      'media' => 'all',
      'preprocess' => TRUE,
      'data' => $data,
      'browsers' => array(),
    );
    $options['browsers'] += array(
      'IE' => TRUE,
      '!IE' => TRUE,
    );

    // Files with a query string cannot be preprocessed.
    if ($options['type'] === 'file' && $options['preprocess'] && strpos($options['data'], '?') !== FALSE) {
      $options['preprocess'] = FALSE;
    }

    // Always add a tiny value to the weight, to conserve the insertion order.
    $options['weight'] += count($css) / 1000;

    // Add the data to the CSS array depending on the type.
    switch ($options['type']) {
      case 'inline':
        // For inline stylesheets, we don't want to use the $data as the array
        // key as $data could be a very long string of CSS.
        $css[] = $options;
        break;
      default:
        // Local and external files must keep their name as the associative key
        // so the same CSS file is not be added twice.
        $css[$data] = $options;
    }
  }

  return $css;
}

/**
 * Returns a themed representation of all stylesheets to attach to the page.
 *
 * It loads the CSS in order, with 'module' first, then 'theme' afterwards.
 * This ensures proper cascading of styles so themes can easily override
 * module styles through CSS selectors.
 *
 * Themes may replace module-defined CSS files by adding a stylesheet with the
 * same filename. For example, themes/bartik/system-menus.css would replace
 * modules/system/system-menus.css. This allows themes to override complete
 * CSS files, rather than specific selectors, when necessary.
 *
 * If the original CSS file is being overridden by a theme, the theme is
 * responsible for supplying an accompanying RTL CSS file to replace the
 * module's.
 *
 * @param $css
 *   (optional) An array of CSS files. If no array is provided, the default
 *   stylesheets array is used instead.
 * @param $skip_alter
 *   (optional) If set to TRUE, this function skips calling drupal_alter() on
 *   $css, useful when the calling function passes a $css array that has already
 *   been altered.
 *
 * @return
 *   A string of XHTML CSS tags.
 *
 * @see drupal_add_css()
 */
function drupal_get_css($css = NULL, $skip_alter = FALSE) {
  if (!isset($css)) {
    $css = drupal_add_css();
  }

  // Allow modules and themes to alter the CSS items.
  if (!$skip_alter) {
    drupal_alter('css', $css);
  }

  // Sort CSS items, so that they appear in the correct order.
  uasort($css, 'drupal_sort_css_js');

  // Provide the page with information about the individual CSS files used,
  // information not otherwise available when CSS aggregation is enabled. The
  // setting is attached later in this function, but is set here, so that CSS
  // files removed below are still considered "used" and prevented from being
  // added in a later AJAX request.
  // Skip if no files were added to the page or jQuery.extend() will overwrite
  // the Drupal.settings.ajaxPageState.css object with an empty array.
  if (!empty($css)) {
    // Cast the array to an object to be on the safe side even if not empty.
    $setting['ajaxPageState']['css'] = (object) array_fill_keys(array_keys($css), 1);
  }

  // Remove the overridden CSS files. Later CSS files override former ones.
  $previous_item = array();
  foreach ($css as $key => $item) {
    if ($item['type'] == 'file') {
      // If defined, force a unique basename for this file.
      $basename = isset($item['basename']) ? $item['basename'] : drupal_basename($item['data']);
      if (isset($previous_item[$basename])) {
        // Remove the previous item that shared the same base name.
        unset($css[$previous_item[$basename]]);
      }
      $previous_item[$basename] = $key;
    }
  }

  // Render the HTML needed to load the CSS.
  $styles = array(
    '#type' => 'styles',
    '#items' => $css,
  );

  if (!empty($setting)) {
    $styles['#attached']['js'][] = array('type' => 'setting', 'data' => $setting);
  }

  return drupal_render($styles);
}

/**
 * Sorts CSS and JavaScript resources.
 *
 * Callback for uasort() within:
 * - drupal_get_css()
 * - drupal_get_js()
 *
 * This sort order helps optimize front-end performance while providing modules
 * and themes with the necessary control for ordering the CSS and JavaScript
 * appearing on a page.
 *
 * @param $a
 *   First item for comparison. The compared items should be associative arrays
 *   of member items from drupal_add_css() or drupal_add_js().
 * @param $b
 *   Second item for comparison.
 *
 * @see drupal_add_css()
 * @see drupal_add_js()
 */
function drupal_sort_css_js($a, $b) {
  // First order by group, so that, for example, all items in the CSS_SYSTEM
  // group appear before items in the CSS_DEFAULT group, which appear before
  // all items in the CSS_THEME group. Modules may create additional groups by
  // defining their own constants.
  if ($a['group'] < $b['group']) {
    return -1;
  }
  elseif ($a['group'] > $b['group']) {
    return 1;
  }
  // Within a group, order all infrequently needed, page-specific files after
  // common files needed throughout the website. Separating this way allows for
  // the aggregate file generated for all of the common files to be reused
  // across a site visit without being cut by a page using a less common file.
  elseif ($a['every_page'] && !$b['every_page']) {
    return -1;
  }
  elseif (!$a['every_page'] && $b['every_page']) {
    return 1;
  }
  // Finally, order by weight.
  elseif ($a['weight'] < $b['weight']) {
    return -1;
  }
  elseif ($a['weight'] > $b['weight']) {
    return 1;
  }
  else {
    return 0;
  }
}

/**
 * Default callback to group CSS items.
 *
 * This function arranges the CSS items that are in the #items property of the
 * styles element into groups. Arranging the CSS items into groups serves two
 * purposes. When aggregation is enabled, files within a group are aggregated
 * into a single file, significantly improving page loading performance by
 * minimizing network traffic overhead. When aggregation is disabled, grouping
 * allows multiple files to be loaded from a single STYLE tag, enabling sites
 * with many modules enabled or a complex theme being used to stay within IE's
 * 31 CSS inclusion tag limit: http://drupal.org/node/228818.
 *
 * This function puts multiple items into the same group if they are groupable
 * and if they are for the same 'media' and 'browsers'. Items of the 'file' type
 * are groupable if their 'preprocess' flag is TRUE, items of the 'inline' type
 * are always groupable, and items of the 'external' type are never groupable.
 * This function also ensures that the process of grouping items does not change
 * their relative order. This requirement may result in multiple groups for the
 * same type, media, and browsers, if needed to accommodate other items in
 * between.
 *
 * @param $css
 *   An array of CSS items, as returned by drupal_add_css(), but after
 *   alteration performed by drupal_get_css().
 *
 * @return
 *   An array of CSS groups. Each group contains the same keys (e.g., 'media',
 *   'data', etc.) as a CSS item from the $css parameter, with the value of
 *   each key applying to the group as a whole. Each group also contains an
 *   'items' key, which is the subset of items from $css that are in the group.
 *
 * @see drupal_pre_render_styles()
 * @see system_element_info()
 */
function drupal_group_css($css) {
  $groups = array();
  // If a group can contain multiple items, we track the information that must
  // be the same for each item in the group, so that when we iterate the next
  // item, we can determine if it can be put into the current group, or if a
  // new group needs to be made for it.
  $current_group_keys = NULL;
  // When creating a new group, we pre-increment $i, so by initializing it to
  // -1, the first group will have index 0.
  $i = -1;
  foreach ($css as $item) {
    // The browsers for which the CSS item needs to be loaded is part of the
    // information that determines when a new group is needed, but the order of
    // keys in the array doesn't matter, and we don't want a new group if all
    // that's different is that order.
    ksort($item['browsers']);

    // If the item can be grouped with other items, set $group_keys to an array
    // of information that must be the same for all items in its group. If the
    // item can't be grouped with other items, set $group_keys to FALSE. We
    // put items into a group that can be aggregated together: whether they will
    // be aggregated is up to the _drupal_css_aggregate() function or an
    // override of that function specified in hook_css_alter(), but regardless
    // of the details of that function, a group represents items that can be
    // aggregated. Since a group may be rendered with a single HTML tag, all
    // items in the group must share the same information that would need to be
    // part of that HTML tag.
    switch ($item['type']) {
      case 'file':
        // Group file items if their 'preprocess' flag is TRUE.
        // Help ensure maximum reuse of aggregate files by only grouping
        // together items that share the same 'group' value and 'every_page'
        // flag. See drupal_add_css() for details about that.
        $group_keys = $item['preprocess'] ? array($item['type'], $item['group'], $item['every_page'], $item['media'], $item['browsers']) : FALSE;
        break;
      case 'inline':
        // Always group inline items.
        $group_keys = array($item['type'], $item['media'], $item['browsers']);
        break;
      case 'external':
        // Do not group external items.
        $group_keys = FALSE;
        break;
    }

    // If the group keys don't match the most recent group we're working with,
    // then a new group must be made.
    if ($group_keys !== $current_group_keys) {
      $i++;
      // Initialize the new group with the same properties as the first item
      // being placed into it. The item's 'data' and 'weight' properties are
      // unique to the item and should not be carried over to the group.
      $groups[$i] = $item;
      unset($groups[$i]['data'], $groups[$i]['weight']);
      $groups[$i]['items'] = array();
      $current_group_keys = $group_keys ? $group_keys : NULL;
    }

    // Add the item to the current group.
    $groups[$i]['items'][] = $item;
  }
  return $groups;
}

/**
 * Default callback to aggregate CSS files and inline content.
 *
 * Having the browser load fewer CSS files results in much faster page loads
 * than when it loads many small files. This function aggregates files within
 * the same group into a single file unless the site-wide setting to do so is
 * disabled (commonly the case during site development). To optimize download,
 * it also compresses the aggregate files by removing comments, whitespace, and
 * other unnecessary content. Additionally, this functions aggregates inline
 * content together, regardless of the site-wide aggregation setting.
 *
 * @param $css_groups
 *   An array of CSS groups as returned by drupal_group_css(). This function
 *   modifies the group's 'data' property for each group that is aggregated.
 *
 * @see drupal_group_css()
 * @see drupal_pre_render_styles()
 * @see system_element_info()
 */
function drupal_aggregate_css(&$css_groups) {
  $preprocess_css = (variable_get('preprocess_css', FALSE) && (!defined('MAINTENANCE_MODE') || MAINTENANCE_MODE != 'update'));

  // For each group that needs aggregation, aggregate its items.
  foreach ($css_groups as $key => $group) {
    switch ($group['type']) {
      // If a file group can be aggregated into a single file, do so, and set
      // the group's data property to the file path of the aggregate file.
      case 'file':
        if ($group['preprocess'] && $preprocess_css) {
          $css_groups[$key]['data'] = drupal_build_css_cache($group['items']);
        }
        break;
      // Aggregate all inline CSS content into the group's data property.
      case 'inline':
        $css_groups[$key]['data'] = '';
        foreach ($group['items'] as $item) {
          $css_groups[$key]['data'] .= drupal_load_stylesheet_content($item['data'], $item['preprocess']);
        }
        break;
    }
  }
}

/**
 * #pre_render callback to add the elements needed for CSS tags to be rendered.
 *
 * For production websites, LINK tags are preferable to STYLE tags with @import
 * statements, because:
 * - They are the standard tag intended for linking to a resource.
 * - On Firefox 2 and perhaps other browsers, CSS files included with @import
 *   statements don't get saved when saving the complete web page for offline
 *   use: http://drupal.org/node/145218.
 * - On IE, if only LINK tags and no @import statements are used, all the CSS
 *   files are downloaded in parallel, resulting in faster page load, but if
 *   @import statements are used and span across multiple STYLE tags, all the
 *   ones from one STYLE tag must be downloaded before downloading begins for
 *   the next STYLE tag. Furthermore, IE7 does not support media declaration on
 *   the @import statement, so multiple STYLE tags must be used when different
 *   files are for different media types. Non-IE browsers always download in
 *   parallel, so this is an IE-specific performance quirk:
 *   http://www.stevesouders.com/blog/2009/04/09/dont-use-import/.
 *
 * However, IE has an annoying limit of 31 total CSS inclusion tags
 * (http://drupal.org/node/228818) and LINK tags are limited to one file per
 * tag, whereas STYLE tags can contain multiple @import statements allowing
 * multiple files to be loaded per tag. When CSS aggregation is disabled, a
 * Drupal site can easily have more than 31 CSS files that need to be loaded, so
 * using LINK tags exclusively would result in a site that would display
 * incorrectly in IE. Depending on different needs, different strategies can be
 * employed to decide when to use LINK tags and when to use STYLE tags.
 *
 * The strategy employed by this function is to use LINK tags for all aggregate
 * files and for all files that cannot be aggregated (e.g., if 'preprocess' is
 * set to FALSE or the type is 'external'), and to use STYLE tags for groups
 * of files that could be aggregated together but aren't (e.g., if the site-wide
 * aggregation setting is disabled). This results in all LINK tags when
 * aggregation is enabled, a guarantee that as many or only slightly more tags
 * are used with aggregation disabled than enabled (so that if the limit were to
 * be crossed with aggregation enabled, the site developer would also notice the
 * problem while aggregation is disabled), and an easy way for a developer to
 * view HTML source while aggregation is disabled and know what files will be
 * aggregated together when aggregation becomes enabled.
 *
 * This function evaluates the aggregation enabled/disabled condition on a group
 * by group basis by testing whether an aggregate file has been made for the
 * group rather than by testing the site-wide aggregation setting. This allows
 * this function to work correctly even if modules have implemented custom
 * logic for grouping and aggregating files.
 *
 * @param $element
 *   A render array containing:
 *   - '#items': The CSS items as returned by drupal_add_css() and altered by
 *     drupal_get_css().
 *   - '#group_callback': A function to call to group #items to enable the use
 *     of fewer tags by aggregating files and/or using multiple @import
 *     statements within a single tag.
 *   - '#aggregate_callback': A function to call to aggregate the items within
 *     the groups arranged by the #group_callback function.
 *
 * @return
 *   A render array that will render to a string of XHTML CSS tags.
 *
 * @see drupal_get_css()
 */
function drupal_pre_render_styles($elements) {
  // Group and aggregate the items.
  if (isset($elements['#group_callback'])) {
    $elements['#groups'] = $elements['#group_callback']($elements['#items']);
  }
  if (isset($elements['#aggregate_callback'])) {
    $elements['#aggregate_callback']($elements['#groups']);
  }

  // A dummy query-string is added to filenames, to gain control over
  // browser-caching. The string changes on every update or full cache
  // flush, forcing browsers to load a new copy of the files, as the
  // URL changed.
  $query_string = variable_get('css_js_query_string', '0');

  // For inline CSS to validate as XHTML, all CSS containing XHTML needs to be
  // wrapped in CDATA. To make that backwards compatible with HTML 4, we need to
  // comment out the CDATA-tag.
  $embed_prefix = "\n<!--/*--><![CDATA[/*><!--*/\n";
  $embed_suffix = "\n/*]]>*/-->\n";

  // Defaults for LINK and STYLE elements.
  $link_element_defaults = array(
    '#type' => 'html_tag',
    '#tag' => 'link',
    '#attributes' => array(
      'type' => 'text/css',
      'rel' => 'stylesheet',
    ),
  );
  $style_element_defaults = array(
    '#type' => 'html_tag',
    '#tag' => 'style',
    '#attributes' => array(
      'type' => 'text/css',
    ),
  );

  // Loop through each group.
  foreach ($elements['#groups'] as $group) {
    switch ($group['type']) {
      // For file items, there are three possibilites.
      // - The group has been aggregated: in this case, output a LINK tag for
      //   the aggregate file.
      // - The group can be aggregated but has not been (most likely because
      //   the site administrator disabled the site-wide setting): in this case,
      //   output as few STYLE tags for the group as possible, using @import
      //   statement for each file in the group. This enables us to stay within
      //   IE's limit of 31 total CSS inclusion tags.
      // - The group contains items not eligible for aggregation (their
      //   'preprocess' flag has been set to FALSE): in this case, output a LINK
      //   tag for each file.
      case 'file':
        // The group has been aggregated into a single file: output a LINK tag
        // for the aggregate file.
        if (isset($group['data'])) {
          $element = $link_element_defaults;
          $element['#attributes']['href'] = file_create_url($group['data']);
          $element['#attributes']['media'] = $group['media'];
          $element['#browsers'] = $group['browsers'];
          $elements[] = $element;
        }
        // The group can be aggregated, but hasn't been: combine multiple items
        // into as few STYLE tags as possible.
        elseif ($group['preprocess']) {
          $import = array();
          foreach ($group['items'] as $item) {
            // A theme's .info file may have an entry for a file that doesn't
            // exist as a way of overriding a module or base theme CSS file from
            // being added to the page. Normally, file_exists() calls that need
            // to run for every page request should be minimized, but this one
            // is okay, because it only runs when CSS aggregation is disabled.
            // On a server under heavy enough load that file_exists() calls need
            // to be minimized, CSS aggregation should be enabled, in which case
            // this code is not run. When aggregation is enabled,
            // drupal_load_stylesheet() checks file_exists(), but only when
            // building the aggregate file, which is then reused for many page
            // requests.
            if (file_exists($item['data'])) {
              // The dummy query string needs to be added to the URL to control
              // browser-caching. IE7 does not support a media type on the
              // @import statement, so we instead specify the media for the
              // group on the STYLE tag.
              $import[] = '@import url("' . check_plain(file_create_url($item['data']) . '?' . $query_string) . '");';
            }
          }
          // In addition to IE's limit of 31 total CSS inclusion tags, it also
          // has a limit of 31 @import statements per STYLE tag.
          while (!empty($import)) {
            $import_batch = array_slice($import, 0, 31);
            $import = array_slice($import, 31);
            $element = $style_element_defaults;
            // This simplifies the JavaScript regex, allowing each line
            // (separated by \n) to be treated as a completely different string.
            // This means that we can use ^ and $ on one line at a time, and not
            // worry about style tags since they'll never match the regex.
            $element['#value'] = "\n" . implode("\n", $import_batch) . "\n";
            $element['#attributes']['media'] = $group['media'];
            $element['#browsers'] = $group['browsers'];
            $elements[] = $element;
          }
        }
        // The group contains items ineligible for aggregation: output a LINK
        // tag for each file.
        else {
          foreach ($group['items'] as $item) {
            $element = $link_element_defaults;
            // We do not check file_exists() here, because this code runs for
            // files whose 'preprocess' is set to FALSE, and therefore, even
            // when aggregation is enabled, and we want to avoid needlessly
            // taxing a server that may be under heavy load. The file_exists()
            // performed above for files whose 'preprocess' is TRUE is done for
            // the benefit of theme .info files, but code that deals with files
            // whose 'preprocess' is FALSE is responsible for ensuring the file
            // exists.
            // The dummy query string needs to be added to the URL to control
            // browser-caching.
            $query_string_separator = (strpos($item['data'], '?') !== FALSE) ? '&' : '?';
            $element['#attributes']['href'] = file_create_url($item['data']) . $query_string_separator . $query_string;
            $element['#attributes']['media'] = $item['media'];
            $element['#browsers'] = $group['browsers'];
            $elements[] = $element;
          }
        }
        break;
      // For inline content, the 'data' property contains the CSS content. If
      // the group's 'data' property is set, then output it in a single STYLE
      // tag. Otherwise, output a separate STYLE tag for each item.
      case 'inline':
        if (isset($group['data'])) {
          $element = $style_element_defaults;
          $element['#value'] = $group['data'];
          $element['#value_prefix'] = $embed_prefix;
          $element['#value_suffix'] = $embed_suffix;
          $element['#attributes']['media'] = $group['media'];
          $element['#browsers'] = $group['browsers'];
          $elements[] = $element;
        }
        else {
          foreach ($group['items'] as $item) {
            $element = $style_element_defaults;
            $element['#value'] = $item['data'];
            $element['#value_prefix'] = $embed_prefix;
            $element['#value_suffix'] = $embed_suffix;
            $element['#attributes']['media'] = $item['media'];
            $element['#browsers'] = $group['browsers'];
            $elements[] = $element;
          }
        }
        break;
      // Output a LINK tag for each external item. The item's 'data' property
      // contains the full URL.
      case 'external':
        foreach ($group['items'] as $item) {
          $element = $link_element_defaults;
          $element['#attributes']['href'] = $item['data'];
          $element['#attributes']['media'] = $item['media'];
          $element['#browsers'] = $group['browsers'];
          $elements[] = $element;
        }
        break;
    }
  }

  return $elements;
}

/**
 * Aggregates and optimizes CSS files into a cache file in the files directory.
 *
 * The file name for the CSS cache file is generated from the hash of the
 * aggregated contents of the files in $css. This forces proxies and browsers
 * to download new CSS when the CSS changes.
 *
 * The cache file name is retrieved on a page load via a lookup variable that
 * contains an associative array. The array key is the hash of the file names
 * in $css while the value is the cache file name. The cache file is generated
 * in two cases. First, if there is no file name value for the key, which will
 * happen if a new file name has been added to $css or after the lookup
 * variable is emptied to force a rebuild of the cache. Second, the cache file
 * is generated if it is missing on disk. Old cache files are not deleted
 * immediately when the lookup variable is emptied, but are deleted after a set
 * period by drupal_delete_file_if_stale(). This ensures that files referenced
 * by a cached page will still be available.
 *
 * @param $css
 *   An array of CSS files to aggregate and compress into one file.
 *
 * @return
 *   The URI of the CSS cache file, or FALSE if the file could not be saved.
 */
function drupal_build_css_cache($css) {
  $data = '';
  $uri = '';
  $map = variable_get('drupal_css_cache_files', array());
  // Create a new array so that only the file names are used to create the hash.
  // This prevents new aggregates from being created unnecessarily.
  $css_data = array();
  foreach ($css as $css_file) {
    $css_data[] = $css_file['data'];
  }
  $key = hash('sha256', serialize($css_data));
  if (isset($map[$key])) {
    $uri = $map[$key];
  }

  if (empty($uri) || !file_exists($uri)) {
    // Build aggregate CSS file.
    foreach ($css as $stylesheet) {
      // Only 'file' stylesheets can be aggregated.
      if ($stylesheet['type'] == 'file') {
        $contents = drupal_load_stylesheet($stylesheet['data'], TRUE);

        // Build the base URL of this CSS file: start with the full URL.
        $css_base_url = file_create_url($stylesheet['data']);
        // Move to the parent.
        $css_base_url = substr($css_base_url, 0, strrpos($css_base_url, '/'));
        // Simplify to a relative URL if the stylesheet URL starts with the
        // base URL of the website.
        if (substr($css_base_url, 0, strlen($GLOBALS['base_root'])) == $GLOBALS['base_root']) {
          $css_base_url = substr($css_base_url, strlen($GLOBALS['base_root']));
        }

        _drupal_build_css_path(NULL, $css_base_url . '/');
        // Anchor all paths in the CSS with its base URL, ignoring external and absolute paths.
        $data .= preg_replace_callback('/url\(\s*[\'"]?(?![a-z]+:|\/+)([^\'")]+)[\'"]?\s*\)/i', '_drupal_build_css_path', $contents);
      }
    }

    // Per the W3C specification at http://www.w3.org/TR/REC-CSS2/cascade.html#at-import,
    // @import rules must proceed any other style, so we move those to the top.
    $regexp = '/@import[^;]+;/i';
    preg_match_all($regexp, $data, $matches);
    $data = preg_replace($regexp, '', $data);
    $data = implode('', $matches[0]) . $data;

    // Prefix filename to prevent blocking by firewalls which reject files
    // starting with "ad*".
    $filename = 'css_' . drupal_hash_base64($data) . '.css';
    // Create the css/ within the files folder.
    $csspath = 'public://css';
    $uri = $csspath . '/' . $filename;
    // Create the CSS file.
    file_prepare_directory($csspath, FILE_CREATE_DIRECTORY);
    if (!file_exists($uri) && !file_unmanaged_save_data($data, $uri, FILE_EXISTS_REPLACE)) {
      return FALSE;
    }
    // If CSS gzip compression is enabled, clean URLs are enabled (which means
    // that rewrite rules are working) and the zlib extension is available then
    // create a gzipped version of this file. This file is served conditionally
    // to browsers that accept gzip using .htaccess rules.
    if (variable_get('css_gzip_compression', TRUE) && variable_get('clean_url', 0) && extension_loaded('zlib')) {
      if (!file_exists($uri . '.gz') && !file_unmanaged_save_data(gzencode($data, 9, FORCE_GZIP), $uri . '.gz', FILE_EXISTS_REPLACE)) {
        return FALSE;
      }
    }
    // Save the updated map.
    $map[$key] = $uri;
    variable_set('drupal_css_cache_files', $map);
  }
  return $uri;
}

/**
 * Prefixes all paths within a CSS file for drupal_build_css_cache().
 */
function _drupal_build_css_path($matches, $base = NULL) {
  $_base = &drupal_static(__FUNCTION__);
  // Store base path for preg_replace_callback.
  if (isset($base)) {
    $_base = $base;
  }

  // Prefix with base and remove '../' segments where possible.
  $path = $_base . $matches[1];
  $last = '';
  while ($path != $last) {
    $last = $path;
    $path = preg_replace('`(^|/)(?!\.\./)([^/]+)/\.\./`', '$1', $path);
  }
  return 'url(' . $path . ')';
}

/**
 * Loads the stylesheet and resolves all @import commands.
 *
 * Loads a stylesheet and replaces @import commands with the contents of the
 * imported file. Use this instead of file_get_contents when processing
 * stylesheets.
 *
 * The returned contents are compressed removing white space and comments only
 * when CSS aggregation is enabled. This optimization will not apply for
 * color.module enabled themes with CSS aggregation turned off.
 *
 * @param $file
 *   Name of the stylesheet to be processed.
 * @param $optimize
 *   Defines if CSS contents should be compressed or not.
 * @param $reset_basepath
 *   Used internally to facilitate recursive resolution of @import commands.
 *
 * @return
 *   Contents of the stylesheet, including any resolved @import commands.
 */
function drupal_load_stylesheet($file, $optimize = NULL, $reset_basepath = TRUE) {
  // These statics are not cache variables, so we don't use drupal_static().
  static $_optimize, $basepath;
  if ($reset_basepath) {
    $basepath = '';
  }
  // Store the value of $optimize for preg_replace_callback with nested
  // @import loops.
  if (isset($optimize)) {
    $_optimize = $optimize;
  }

  // Stylesheets are relative one to each other. Start by adding a base path
  // prefix provided by the parent stylesheet (if necessary).
  if ($basepath && !file_uri_scheme($file)) {
    $file = $basepath . '/' . $file;
  }
  // Store the parent base path to restore it later.
  $parent_base_path = $basepath;
  // Set the current base path to process possible child imports.
  $basepath = dirname($file);

  // Load the CSS stylesheet. We suppress errors because themes may specify
  // stylesheets in their .info file that don't exist in the theme's path,
  // but are merely there to disable certain module CSS files.
  $content = '';
  if ($contents = @file_get_contents($file)) {
    // Return the processed stylesheet.
    $content = drupal_load_stylesheet_content($contents, $_optimize);
  }

  // Restore the parent base path as the file and its childen are processed.
  $basepath = $parent_base_path;
  return $content;
}

/**
 * Processes the contents of a stylesheet for aggregation.
 *
 * @param $contents
 *   The contents of the stylesheet.
 * @param $optimize
 *   (optional) Boolean whether CSS contents should be minified. Defaults to
 *   FALSE.
 *
 * @return
 *   Contents of the stylesheet including the imported stylesheets.
 */
function drupal_load_stylesheet_content($contents, $optimize = FALSE) {
  // Remove multiple charset declarations for standards compliance (and fixing Safari problems).
  $contents = preg_replace('/^@charset\s+[\'"](\S*?)\b[\'"];/i', '', $contents);

  if ($optimize) {
    // Perform some safe CSS optimizations.
    // Regexp to match comment blocks.
    $comment     = '/\*[^*]*\*+(?:[^/*][^*]*\*+)*/';
    // Regexp to match double quoted strings.
    $double_quot = '"[^"\\\\]*(?:\\\\.[^"\\\\]*)*"';
    // Regexp to match single quoted strings.
    $single_quot = "'[^'\\\\]*(?:\\\\.[^'\\\\]*)*'";
    // Strip all comment blocks, but keep double/single quoted strings.
    $contents = preg_replace(
      "<($double_quot|$single_quot)|$comment>Ss",
      "$1",
      $contents
    );
    // Remove certain whitespace.
    // There are different conditions for removing leading and trailing
    // whitespace.
    // @see http://php.net/manual/regexp.reference.subpatterns.php
    $contents = preg_replace('<
      # Strip leading and trailing whitespace.
        \s*([@{};,])\s*
      # Strip only leading whitespace from:
      # - Closing parenthesis: Retain "@media (bar) and foo".
      | \s+([\)])
      # Strip only trailing whitespace from:
      # - Opening parenthesis: Retain "@media (bar) and foo".
      # - Colon: Retain :pseudo-selectors.
      | ([\(:])\s+
    >xS',
      // Only one of the three capturing groups will match, so its reference
      // will contain the wanted value and the references for the
      // two non-matching groups will be replaced with empty strings.
      '$1$2$3',
      $contents
    );
    // End the file with a new line.
    $contents = trim($contents);
    $contents .= "\n";
  }

  // Replaces @import commands with the actual stylesheet content.
  // This happens recursively but omits external files.
  $contents = preg_replace_callback('/@import\s*(?:url\(\s*)?[\'"]?(?![a-z]+:)(?!\/\/)([^\'"\()]+)[\'"]?\s*\)?\s*;/', '_drupal_load_stylesheet', $contents);
  return $contents;
}

/**
 * Loads stylesheets recursively and returns contents with corrected paths.
 *
 * This function is used for recursive loading of stylesheets and
 * returns the stylesheet content with all url() paths corrected.
 */
function _drupal_load_stylesheet($matches) {
  $filename = $matches[1];
  // Load the imported stylesheet and replace @import commands in there as well.
  $file = drupal_load_stylesheet($filename, NULL, FALSE);

  // Determine the file's directory.
  $directory = dirname($filename);
  // If the file is in the current directory, make sure '.' doesn't appear in
  // the url() path.
  $directory = $directory == '.' ? '' : $directory .'/';

  // Alter all internal url() paths. Leave external paths alone. We don't need
  // to normalize absolute paths here (i.e. remove folder/... segments) because
  // that will be done later.
  return preg_replace('/url\(\s*([\'"]?)(?![a-z]+:|\/+)([^\'")]+)([\'"]?)\s*\)/i', 'url(\1' . $directory . '\2\3)', $file);
}

/**
 * Deletes old cached CSS files.
 */
function drupal_clear_css_cache() {
  variable_del('drupal_css_cache_files');
  file_scan_directory('public://css', '/.*/', array('callback' => 'drupal_delete_file_if_stale'));
}

/**
 * Callback to delete files modified more than a set time ago.
 */
function drupal_delete_file_if_stale($uri) {
  // Default stale file threshold is 30 days.
  if (REQUEST_TIME - filemtime($uri) > variable_get('drupal_stale_file_threshold', 2592000)) {
    file_unmanaged_delete($uri);
  }
}

/**
 * Prepares a string for use as a CSS identifier (element, class, or ID name).
 *
 * http://www.w3.org/TR/CSS21/syndata.html#characters shows the syntax for valid
 * CSS identifiers (including element names, classes, and IDs in selectors.)
 *
 * @param $identifier
 *   The identifier to clean.
 * @param $filter
 *   An array of string replacements to use on the identifier.
 *
 * @return
 *   The cleaned identifier.
 */
function drupal_clean_css_identifier($identifier, $filter = array(' ' => '-', '_' => '-', '/' => '-', '[' => '-', ']' => '')) {
  // By default, we filter using Drupal's coding standards.
  $identifier = strtr($identifier, $filter);

  // Valid characters in a CSS identifier are:
  // - the hyphen (U+002D)
  // - a-z (U+0030 - U+0039)
  // - A-Z (U+0041 - U+005A)
  // - the underscore (U+005F)
  // - 0-9 (U+0061 - U+007A)
  // - ISO 10646 characters U+00A1 and higher
  // We strip out any character not in the above list.
  $identifier = preg_replace('/[^\x{002D}\x{0030}-\x{0039}\x{0041}-\x{005A}\x{005F}\x{0061}-\x{007A}\x{00A1}-\x{FFFF}]/u', '', $identifier);

  return $identifier;
}

/**
 * Prepares a string for use as a valid class name.
 *
 * Do not pass one string containing multiple classes as they will be
 * incorrectly concatenated with dashes, i.e. "one two" will become "one-two".
 *
 * @param $class
 *   The class name to clean.
 *
 * @return
 *   The cleaned class name.
 */
function drupal_html_class($class) {
  // The output of this function will never change, so this uses a normal
  // static instead of drupal_static().
  static $classes = array();

  if (!isset($classes[$class])) {
    $classes[$class] = drupal_clean_css_identifier(drupal_strtolower($class));
  }
  return $classes[$class];
}

/**
 * Prepares a string for use as a valid HTML ID and guarantees uniqueness.
 *
 * This function ensures that each passed HTML ID value only exists once on the
 * page. By tracking the already returned ids, this function enables forms,
 * blocks, and other content to be output multiple times on the same page,
 * without breaking (X)HTML validation.
 *
 * For already existing IDs, a counter is appended to the ID string. Therefore,
 * JavaScript and CSS code should not rely on any value that was generated by
 * this function and instead should rely on manually added CSS classes or
 * similarly reliable constructs.
 *
 * Two consecutive hyphens separate the counter from the original ID. To manage
 * uniqueness across multiple Ajax requests on the same page, Ajax requests
 * POST an array of all IDs currently present on the page, which are used to
 * prime this function's cache upon first invocation.
 *
 * To allow reverse-parsing of IDs submitted via Ajax, any multiple consecutive
 * hyphens in the originally passed $id are replaced with a single hyphen.
 *
 * @param $id
 *   The ID to clean.
 *
 * @return
 *   The cleaned ID.
 */
function drupal_html_id($id) {
  // If this is an Ajax request, then content returned by this page request will
  // be merged with content already on the base page. The HTML IDs must be
  // unique for the fully merged content. Therefore, initialize $seen_ids to
  // take into account IDs that are already in use on the base page.
  $seen_ids_init = &drupal_static(__FUNCTION__ . ':init');
  if (!isset($seen_ids_init)) {
    // Ideally, Drupal would provide an API to persist state information about
    // prior page requests in the database, and we'd be able to add this
    // function's $seen_ids static variable to that state information in order
    // to have it properly initialized for this page request. However, no such
    // page state API exists, so instead, ajax.js adds all of the in-use HTML
    // IDs to the POST data of Ajax submissions. Direct use of $_POST is
    // normally not recommended as it could open up security risks, but because
    // the raw POST data is cast to a number before being returned by this
    // function, this usage is safe.
    if (empty($_POST['ajax_html_ids'])) {
      $seen_ids_init = array();
    }
    else {
      // This function ensures uniqueness by appending a counter to the base id
      // requested by the calling function after the first occurrence of that
      // requested id. $_POST['ajax_html_ids'] contains the ids as they were
      // returned by this function, potentially with the appended counter, so
      // we parse that to reconstruct the $seen_ids array.
      if (isset($_POST['ajax_html_ids'][0]) && strpos($_POST['ajax_html_ids'][0], ',') === FALSE) {
        $ajax_html_ids = $_POST['ajax_html_ids'];
      }
      else {
        // jquery.form.js may send the server a comma-separated string as the
        // first element of an array (see http://drupal.org/node/1575060), so
        // we need to convert it to an array in that case.
        $ajax_html_ids = explode(',', $_POST['ajax_html_ids'][0]);
      }
      foreach ($ajax_html_ids as $seen_id) {
        // We rely on '--' being used solely for separating a base id from the
        // counter, which this function ensures when returning an id.
        $parts = explode('--', $seen_id, 2);
        if (!empty($parts[1]) && is_numeric($parts[1])) {
          list($seen_id, $i) = $parts;
        }
        else {
          $i = 1;
        }
        if (!isset($seen_ids_init[$seen_id]) || ($i > $seen_ids_init[$seen_id])) {
          $seen_ids_init[$seen_id] = $i;
        }
      }
    }
  }
  $seen_ids = &drupal_static(__FUNCTION__, $seen_ids_init);

  $id = strtr(drupal_strtolower($id), array(' ' => '-', '_' => '-', '[' => '-', ']' => ''));

  // As defined in http://www.w3.org/TR/html4/types.html#type-name, HTML IDs can
  // only contain letters, digits ([0-9]), hyphens ("-"), underscores ("_"),
  // colons (":"), and periods ("."). We strip out any character not in that
  // list. Note that the CSS spec doesn't allow colons or periods in identifiers
  // (http://www.w3.org/TR/CSS21/syndata.html#characters), so we strip those two
  // characters as well.
  $id = preg_replace('/[^A-Za-z0-9\-_]/', '', $id);

  // Removing multiple consecutive hyphens.
  $id = preg_replace('/\-+/', '-', $id);
  // Ensure IDs are unique by appending a counter after the first occurrence.
  // The counter needs to be appended with a delimiter that does not exist in
  // the base ID. Requiring a unique delimiter helps ensure that we really do
  // return unique IDs and also helps us re-create the $seen_ids array during
  // Ajax requests.
  if (isset($seen_ids[$id])) {
    $id = $id . '--' . ++$seen_ids[$id];
  }
  else {
    $seen_ids[$id] = 1;
  }

  return $id;
}

/**
 * Provides a standard HTML class name that identifies a page region.
 *
 * It is recommended that template preprocess functions apply this class to any
 * page region that is output by the theme (Drupal core already handles this in
 * the standard template preprocess implementation). Standardizing the class
 * names in this way allows modules to implement certain features, such as
 * drag-and-drop or dynamic Ajax loading, in a theme-independent way.
 *
 * @param $region
 *   The name of the page region (for example, 'page_top' or 'content').
 *
 * @return
 *   An HTML class that identifies the region (for example, 'region-page-top'
 *   or 'region-content').
 *
 * @see template_preprocess_region()
 */
function drupal_region_class($region) {
  return drupal_html_class("region-$region");
}

/**
 * Adds a JavaScript file, setting, or inline code to the page.
 *
 * The behavior of this function depends on the parameters it is called with.
 * Generally, it handles the addition of JavaScript to the page, either as
 * reference to an existing file or as inline code. The following actions can be
 * performed using this function:
 * - Add a file ('file'): Adds a reference to a JavaScript file to the page.
 * - Add inline JavaScript code ('inline'): Executes a piece of JavaScript code
 *   on the current page by placing the code directly in the page (for example,
 *   to tell the user that a new message arrived, by opening a pop up, alert
 *   box, etc.). This should only be used for JavaScript that cannot be executed
 *   from a file. When adding inline code, make sure that you are not relying on
 *   $() being the jQuery function. Wrap your code in
 *   @code (function ($) {... })(jQuery); @endcode
 *   or use jQuery() instead of $().
 * - Add external JavaScript ('external'): Allows the inclusion of external
 *   JavaScript files that are not hosted on the local server. Note that these
 *   external JavaScript references do not get aggregated when preprocessing is
 *   on.
 * - Add settings ('setting'): Adds settings to Drupal's global storage of
 *   JavaScript settings. Per-page settings are required by some modules to
 *   function properly. All settings will be accessible at Drupal.settings.
 *
 * Examples:
 * @code
 *   drupal_add_js('misc/collapse.js');
 *   drupal_add_js('misc/collapse.js', 'file');
 *   drupal_add_js('jQuery(document).ready(function () { alert("Hello!"); });', 'inline');
 *   drupal_add_js('jQuery(document).ready(function () { alert("Hello!"); });',
 *     array('type' => 'inline', 'scope' => 'footer', 'weight' => 5)
 *   );
 *   drupal_add_js('http://example.com/example.js', 'external');
 *   drupal_add_js(array('myModule' => array('key' => 'value')), 'setting');
 * @endcode
 *
 * Calling drupal_static_reset('drupal_add_js') will clear all JavaScript added
 * so far.
 *
 * If JavaScript aggregation is enabled, all JavaScript files added with
 * $options['preprocess'] set to TRUE will be merged into one aggregate file.
 * Preprocessed inline JavaScript will not be aggregated into this single file.
 * Externally hosted JavaScripts are never aggregated.
 *
 * The reason for aggregating the files is outlined quite thoroughly here:
 * http://www.die.net/musings/page_load_time/ "Load fewer external objects. Due
 * to request overhead, one bigger file just loads faster than two smaller ones
 * half its size."
 *
 * $options['preprocess'] should be only set to TRUE when a file is required for
 * all typical visitors and most pages of a site. It is critical that all
 * preprocessed files are added unconditionally on every page, even if the
 * files are not needed on a page. This is normally done by calling
 * drupal_add_js() in a hook_init() implementation.
 *
 * Non-preprocessed files should only be added to the page when they are
 * actually needed.
 *
 * @param $data
 *   (optional) If given, the value depends on the $options parameter, or
 *   $options['type'] if $options is passed as an associative array:
 *   - 'file': Path to the file relative to base_path().
 *   - 'inline': The JavaScript code that should be placed in the given scope.
 *   - 'external': The absolute path to an external JavaScript file that is not
 *     hosted on the local server. These files will not be aggregated if
 *     JavaScript aggregation is enabled.
 *   - 'setting': An associative array with configuration options. The array is
 *     merged directly into Drupal.settings. All modules should wrap their
 *     actual configuration settings in another variable to prevent conflicts in
 *     the Drupal.settings namespace. Items added with a string key will replace
 *     existing settings with that key; items with numeric array keys will be
 *     added to the existing settings array.
 * @param $options
 *   (optional) A string defining the type of JavaScript that is being added in
 *   the $data parameter ('file'/'setting'/'inline'/'external'), or an
 *   associative array. JavaScript settings should always pass the string
 *   'setting' only. Other types can have the following elements in the array:
 *   - type: The type of JavaScript that is to be added to the page. Allowed
 *     values are 'file', 'inline', 'external' or 'setting'. Defaults
 *     to 'file'.
 *   - scope: The location in which you want to place the script. Possible
 *     values are 'header' or 'footer'. If your theme implements different
 *     regions, you can also use these. Defaults to 'header'.
 *   - group: A number identifying the group in which to add the JavaScript.
 *     Available constants are:
 *     - JS_LIBRARY: Any libraries, settings, or jQuery plugins.
 *     - JS_DEFAULT: Any module-layer JavaScript.
 *     - JS_THEME: Any theme-layer JavaScript.
 *     The group number serves as a weight: JavaScript within a lower weight
 *     group is presented on the page before JavaScript within a higher weight
 *     group.
 *   - every_page: For optimal front-end performance when aggregation is
 *     enabled, this should be set to TRUE if the JavaScript is present on every
 *     page of the website for users for whom it is present at all. This
 *     defaults to FALSE. It is set to TRUE for JavaScript files that are added
 *     via module and theme .info files. Modules that add JavaScript within
 *     hook_init() implementations, or from other code that ensures that the
 *     JavaScript is added to all website pages, should also set this flag to
 *     TRUE. All JavaScript files within the same group and that have the
 *     'every_page' flag set to TRUE and do not have 'preprocess' set to FALSE
 *     are aggregated together into a single aggregate file, and that aggregate
 *     file can be reused across a user's entire site visit, leading to faster
 *     navigation between pages. However, JavaScript that is only needed on
 *     pages less frequently visited, can be added by code that only runs for
 *     those particular pages, and that code should not set the 'every_page'
 *     flag. This minimizes the size of the aggregate file that the user needs
 *     to download when first visiting the website. JavaScript without the
 *     'every_page' flag is aggregated into a separate aggregate file. This
 *     other aggregate file is likely to change from page to page, and each new
 *     aggregate file needs to be downloaded when first encountered, so it
 *     should be kept relatively small by ensuring that most commonly needed
 *     JavaScript is added to every page.
 *   - weight: A number defining the order in which the JavaScript is added to
 *     the page relative to other JavaScript with the same 'scope', 'group',
 *     and 'every_page' value. In some cases, the order in which the JavaScript
 *     is presented on the page is very important. jQuery, for example, must be
 *     added to the page before any jQuery code is run, so jquery.js uses the
 *     JS_LIBRARY group and a weight of -20, jquery.once.js (a library drupal.js
 *     depends on) uses the JS_LIBRARY group and a weight of -19, drupal.js uses
 *     the JS_LIBRARY group and a weight of -1, other libraries use the
 *     JS_LIBRARY group and a weight of 0 or higher, and all other scripts use
 *     one of the other group constants. The exact ordering of JavaScript is as
 *     follows:
 *     - First by scope, with 'header' first, 'footer' last, and any other
 *       scopes provided by a custom theme coming in between, as determined by
 *       the theme.
 *     - Then by group.
 *     - Then by the 'every_page' flag, with TRUE coming before FALSE.
 *     - Then by weight.
 *     - Then by the order in which the JavaScript was added. For example, all
 *       else being the same, JavaScript added by a call to drupal_add_js() that
 *       happened later in the page request gets added to the page after one for
 *       which drupal_add_js() happened earlier in the page request.
 *   - requires_jquery: Set this to FALSE if the JavaScript you are adding does
 *     not have a dependency on jQuery. Defaults to TRUE, except for JavaScript
 *     settings where it defaults to FALSE. This is used on sites that have the
 *     'javascript_always_use_jquery' variable set to FALSE; on those sites, if
 *     all the JavaScript added to the page by drupal_add_js() does not have a
 *     dependency on jQuery, then for improved front-end performance Drupal
 *     will not add jQuery and related libraries and settings to the page.
 *   - defer: If set to TRUE, the defer attribute is set on the <script>
 *     tag. Defaults to FALSE.
 *   - cache: If set to FALSE, the JavaScript file is loaded anew on every page
 *     call; in other words, it is not cached. Used only when 'type' references
 *     a JavaScript file. Defaults to TRUE.
 *   - preprocess: If TRUE and JavaScript aggregation is enabled, the script
 *     file will be aggregated. Defaults to TRUE.
 *
 * @return
 *   The current array of JavaScript files, settings, and in-line code,
 *   including Drupal defaults, anything previously added with calls to
 *   drupal_add_js(), and this function call's additions.
 *
 * @see drupal_get_js()
 */
function drupal_add_js($data = NULL, $options = NULL) {
  $javascript = &drupal_static(__FUNCTION__, array());
  $jquery_added = &drupal_static(__FUNCTION__ . ':jquery_added', FALSE);

  // If the $javascript variable has been reset with drupal_static_reset(),
  // jQuery and related files will have been removed from the list, so set the
  // variable back to FALSE to indicate they have not yet been added.
  if (empty($javascript)) {
    $jquery_added = FALSE;
  }

  // Construct the options, taking the defaults into consideration.
  if (isset($options)) {
    if (!is_array($options)) {
      $options = array('type' => $options);
    }
  }
  else {
    $options = array();
  }
  if (isset($options['type']) && $options['type'] == 'setting') {
    $options += array('requires_jquery' => FALSE);
  }
  $options += drupal_js_defaults($data);

  // Preprocess can only be set if caching is enabled.
  $options['preprocess'] = $options['cache'] ? $options['preprocess'] : FALSE;

  // Tweak the weight so that files of the same weight are included in the
  // order of the calls to drupal_add_js().
  $options['weight'] += count($javascript) / 1000;

  if (isset($data)) {
    // Add jquery.js, drupal.js, and related files and settings if they have
    // not been added yet. However, if the 'javascript_always_use_jquery'
    // variable is set to FALSE (indicating that the site does not want jQuery
    // automatically added on all pages) then only add it if a file or setting
    // that requires jQuery is being added also.
    if (!$jquery_added && (variable_get('javascript_always_use_jquery', TRUE) || $options['requires_jquery'])) {
      $jquery_added = TRUE;
      // url() generates the prefix using hook_url_outbound_alter(). Instead of
      // running the hook_url_outbound_alter() again here, extract the prefix
      // from url().
      url('', array('prefix' => &$prefix));
      $default_javascript = array(
        'settings' => array(
          'data' => array(
            array('basePath' => base_path()),
            array('pathPrefix' => empty($prefix) ? '' : $prefix),
          ),
          'type' => 'setting',
          'scope' => 'header',
          'group' => JS_LIBRARY,
          'every_page' => TRUE,
          'weight' => 0,
        ),
        'misc/drupal.js' => array(
          'data' => 'misc/drupal.js',
          'type' => 'file',
          'scope' => 'header',
          'group' => JS_LIBRARY,
          'every_page' => TRUE,
          'weight' => -1,
          'requires_jquery' => TRUE,
          'preprocess' => TRUE,
          'cache' => TRUE,
          'defer' => FALSE,
        ),
      );
      $javascript = drupal_array_merge_deep($javascript, $default_javascript);
      // Register all required libraries.
      drupal_add_library('system', 'jquery', TRUE);
      drupal_add_library('system', 'jquery.once', TRUE);
    }

    switch ($options['type']) {
      case 'setting':
        // All JavaScript settings are placed in the header of the page with
        // the library weight so that inline scripts appear afterwards.
        $javascript['settings']['data'][] = $data;
        break;

      case 'inline':
        $javascript[] = $options;
        break;

      default: // 'file' and 'external'
        // Local and external files must keep their name as the associative key
        // so the same JavaScript file is not added twice.
        $javascript[$options['data']] = $options;
    }
  }
  return $javascript;
}

/**
 * Constructs an array of the defaults that are used for JavaScript items.
 *
 * @param $data
 *   (optional) The default data parameter for the JavaScript item array.
 *
 * @see drupal_get_js()
 * @see drupal_add_js()
 */
function drupal_js_defaults($data = NULL) {
  return array(
    'type' => 'file',
    'group' => JS_DEFAULT,
    'every_page' => FALSE,
    'weight' => 0,
    'requires_jquery' => TRUE,
    'scope' => 'header',
    'cache' => TRUE,
    'defer' => FALSE,
    'preprocess' => TRUE,
    'version' => NULL,
    'data' => $data,
  );
}

/**
 * Returns a themed presentation of all JavaScript code for the current page.
 *
 * References to JavaScript files are placed in a certain order: first, all
 * 'core' files, then all 'module' and finally all 'theme' JavaScript files
 * are added to the page. Then, all settings are output, followed by 'inline'
 * JavaScript code. If running update.php, all preprocessing is disabled.
 *
 * Note that hook_js_alter(&$javascript) is called during this function call
 * to allow alterations of the JavaScript during its presentation. Calls to
 * drupal_add_js() from hook_js_alter() will not be added to the output
 * presentation. The correct way to add JavaScript during hook_js_alter()
 * is to add another element to the $javascript array, deriving from
 * drupal_js_defaults(). See locale_js_alter() for an example of this.
 *
 * @param $scope
 *   (optional) The scope for which the JavaScript rules should be returned.
 *   Defaults to 'header'.
 * @param $javascript
 *   (optional) An array with all JavaScript code. Defaults to the default
 *   JavaScript array for the given scope.
 * @param $skip_alter
 *   (optional) If set to TRUE, this function skips calling drupal_alter() on
 *   $javascript, useful when the calling function passes a $javascript array
 *   that has already been altered.
 *
 * @return
 *   All JavaScript code segments and includes for the scope as HTML tags.
 *
 * @see drupal_add_js()
 * @see locale_js_alter()
 * @see drupal_js_defaults()
 */
function drupal_get_js($scope = 'header', $javascript = NULL, $skip_alter = FALSE) {
  if (!isset($javascript)) {
    $javascript = drupal_add_js();
  }

  // If no JavaScript items have been added, or if the only JavaScript items
  // that have been added are JavaScript settings (which don't do anything
  // without any JavaScript code to use them), then no JavaScript code should
  // be added to the page.
  if (empty($javascript) || (isset($javascript['settings']) && count($javascript) == 1)) {
    return '';
  }

  // Allow modules to alter the JavaScript.
  if (!$skip_alter) {
    drupal_alter('js', $javascript);
  }

  // Filter out elements of the given scope.
  $items = array();
  foreach ($javascript as $key => $item) {
    if ($item['scope'] == $scope) {
      $items[$key] = $item;
    }
  }

  $output = '';
  // The index counter is used to keep aggregated and non-aggregated files in
  // order by weight.
  $index = 1;
  $processed = array();
  $files = array();
  $preprocess_js = (variable_get('preprocess_js', FALSE) && (!defined('MAINTENANCE_MODE') || MAINTENANCE_MODE != 'update'));

  // A dummy query-string is added to filenames, to gain control over
  // browser-caching. The string changes on every update or full cache
  // flush, forcing browsers to load a new copy of the files, as the
  // URL changed. Files that should not be cached (see drupal_add_js())
  // get REQUEST_TIME as query-string instead, to enforce reload on every
  // page request.
  $default_query_string = variable_get('css_js_query_string', '0');

  // For inline JavaScript to validate as XHTML, all JavaScript containing
  // XHTML needs to be wrapped in CDATA. To make that backwards compatible
  // with HTML 4, we need to comment out the CDATA-tag.
  $embed_prefix = "\n<!--//--><![CDATA[//><!--\n";
  $embed_suffix = "\n//--><!]]>\n";

  // Since JavaScript may look for arguments in the URL and act on them, some
  // third-party code might require the use of a different query string.
  $js_version_string = variable_get('drupal_js_version_query_string', 'v=');

  // Sort the JavaScript so that it appears in the correct order.
  uasort($items, 'drupal_sort_css_js');

  // Provide the page with information about the individual JavaScript files
  // used, information not otherwise available when aggregation is enabled.
  $setting['ajaxPageState']['js'] = array_fill_keys(array_keys($items), 1);
  unset($setting['ajaxPageState']['js']['settings']);
  drupal_add_js($setting, 'setting');

  // If we're outputting the header scope, then this might be the final time
  // that drupal_get_js() is running, so add the setting to this output as well
  // as to the drupal_add_js() cache. If $items['settings'] doesn't exist, it's
  // because drupal_get_js() was intentionally passed a $javascript argument
  // stripped off settings, potentially in order to override how settings get
  // output, so in this case, do not add the setting to this output.
  if ($scope == 'header' && isset($items['settings'])) {
    $items['settings']['data'][] = $setting;
  }

  // Loop through the JavaScript to construct the rendered output.
  $element = array(
    '#tag' => 'script',
    '#value' => '',
    '#attributes' => array(
      'type' => 'text/javascript',
    ),
  );
  foreach ($items as $item) {
    $query_string =  empty($item['version']) ? $default_query_string : $js_version_string . $item['version'];

    switch ($item['type']) {
      case 'setting':
        $js_element = $element;
        $js_element['#value_prefix'] = $embed_prefix;
        $js_element['#value'] = 'jQuery.extend(Drupal.settings, ' . drupal_json_encode(drupal_array_merge_deep_array($item['data'])) . ");";
        $js_element['#value_suffix'] = $embed_suffix;
        $output .= theme('html_tag', array('element' => $js_element));
        break;

      case 'inline':
        $js_element = $element;
        if ($item['defer']) {
          $js_element['#attributes']['defer'] = 'defer';
        }
        $js_element['#value_prefix'] = $embed_prefix;
        $js_element['#value'] = $item['data'];
        $js_element['#value_suffix'] = $embed_suffix;
        $processed[$index++] = theme('html_tag', array('element' => $js_element));
        break;

      case 'file':
        $js_element = $element;
        if (!$item['preprocess'] || !$preprocess_js) {
          if ($item['defer']) {
            $js_element['#attributes']['defer'] = 'defer';
          }
          $query_string_separator = (strpos($item['data'], '?') !== FALSE) ? '&' : '?';
          $js_element['#attributes']['src'] = file_create_url($item['data']) . $query_string_separator . ($item['cache'] ? $query_string : REQUEST_TIME);
          $processed[$index++] = theme('html_tag', array('element' => $js_element));
        }
        else {
          // By increasing the index for each aggregated file, we maintain
          // the relative ordering of JS by weight. We also set the key such
          // that groups are split by items sharing the same 'group' value and
          // 'every_page' flag. While this potentially results in more aggregate
          // files, it helps make each one more reusable across a site visit,
          // leading to better front-end performance of a website as a whole.
          // See drupal_add_js() for details.
          $key = 'aggregate_' . $item['group'] . '_' . $item['every_page'] . '_' . $index;
          $processed[$key] = '';
          $files[$key][$item['data']] = $item;
        }
        break;

      case 'external':
        $js_element = $element;
        // Preprocessing for external JavaScript files is ignored.
        if ($item['defer']) {
          $js_element['#attributes']['defer'] = 'defer';
        }
        $js_element['#attributes']['src'] = $item['data'];
        $processed[$index++] = theme('html_tag', array('element' => $js_element));
        break;
    }
  }

  // Aggregate any remaining JS files that haven't already been output.
  if ($preprocess_js && count($files) > 0) {
    foreach ($files as $key => $file_set) {
      $uri = drupal_build_js_cache($file_set);
      // Only include the file if was written successfully. Errors are logged
      // using watchdog.
      if ($uri) {
        $preprocess_file = file_create_url($uri);
        $js_element = $element;
        $js_element['#attributes']['src'] = $preprocess_file;
        $processed[$key] = theme('html_tag', array('element' => $js_element));
      }
    }
  }

  // Keep the order of JS files consistent as some are preprocessed and others are not.
  // Make sure any inline or JS setting variables appear last after libraries have loaded.
  return implode('', $processed) . $output;
}

/**
 * Adds attachments to a render() structure.
 *
 * Libraries, JavaScript, CSS and other types of custom structures are attached
 * to elements using the #attached property. The #attached property is an
 * associative array, where the keys are the attachment types and the values are
 * the attached data. For example:
 * @code
 * $build['#attached'] = array(
 *   'js' => array(drupal_get_path('module', 'taxonomy') . '/taxonomy.js'),
 *   'css' => array(drupal_get_path('module', 'taxonomy') . '/taxonomy.css'),
 * );
 * @endcode
 *
 * 'js', 'css', and 'library' are types that get special handling. For any
 * other kind of attached data, the array key must be the full name of the
 * callback function and each value an array of arguments. For example:
 * @code
 * $build['#attached']['drupal_add_http_header'] = array(
 *   array('Content-Type', 'application/rss+xml; charset=utf-8'),
 * );
 * @endcode
 *
 * External 'js' and 'css' files can also be loaded. For example:
 * @code
 * $build['#attached']['js'] = array(
 *   'http://code.jquery.com/jquery-1.4.2.min.js' => array(
 *     'type' => 'external',
 *   ),
 * );
 * @endcode
 *
 * @param $elements
 *   The structured array describing the data being rendered.
 * @param $group
 *   The default group of JavaScript and CSS being added. This is only applied
 *   to the stylesheets and JavaScript items that don't have an explicit group
 *   assigned to them.
 * @param $dependency_check
 *   When TRUE, will exit if a given library's dependencies are missing. When
 *   set to FALSE, will continue to add the libraries, even though one or more
 *   dependencies are missing. Defaults to FALSE.
 * @param $every_page
 *   Set to TRUE to indicate that the attachments are added to every page on the
 *   site. Only attachments with the every_page flag set to TRUE can participate
 *   in JavaScript/CSS aggregation.
 *
 * @return
 *   FALSE if there were any missing library dependencies; TRUE if all library
 *   dependencies were met.
 *
 * @see drupal_add_library()
 * @see drupal_add_js()
 * @see drupal_add_css()
 * @see drupal_render()
 */
function drupal_process_attached($elements, $group = JS_DEFAULT, $dependency_check = FALSE, $every_page = NULL) {
  // Add defaults to the special attached structures that should be processed differently.
  $elements['#attached'] += array(
    'library' => array(),
    'js' => array(),
    'css' => array(),
  );

  // Add the libraries first.
  $success = TRUE;
  foreach ($elements['#attached']['library'] as $library) {
    if (drupal_add_library($library[0], $library[1], $every_page) === FALSE) {
      $success = FALSE;
      // Exit if the dependency is missing.
      if ($dependency_check) {
        return $success;
      }
    }
  }
  unset($elements['#attached']['library']);

  // Add both the JavaScript and the CSS.
  // The parameters for drupal_add_js() and drupal_add_css() require special
  // handling.
  foreach (array('js', 'css') as $type) {
    foreach ($elements['#attached'][$type] as $data => $options) {
      // If the value is not an array, it's a filename and passed as first
      // (and only) argument.
      if (!is_array($options)) {
        $data = $options;
        $options = NULL;
      }
      // In some cases, the first parameter ($data) is an array. Arrays can't be
      // passed as keys in PHP, so we have to get $data from the value array.
      if (is_numeric($data)) {
        $data = $options['data'];
        unset($options['data']);
      }
      // Apply the default group if it isn't explicitly given.
      if (!isset($options['group'])) {
        $options['group'] = $group;
      }
      // Set the every_page flag if one was passed.
      if (isset($every_page)) {
        $options['every_page'] = $every_page;
      }
      call_user_func('drupal_add_' . $type, $data, $options);
    }
    unset($elements['#attached'][$type]);
  }

  // Add additional types of attachments specified in the render() structure.
  // Libraries, JavaScript and CSS have been added already, as they require
  // special handling.
  foreach ($elements['#attached'] as $callback => $options) {
    if (function_exists($callback)) {
      foreach ($elements['#attached'][$callback] as $args) {
        call_user_func_array($callback, $args);
      }
    }
  }

  return $success;
}

/**
 * Adds JavaScript to change the state of an element based on another element.
 *
 * A "state" means a certain property on a DOM element, such as "visible" or
 * "checked". A state can be applied to an element, depending on the state of
 * another element on the page. In general, states depend on HTML attributes and
 * DOM element properties, which change due to user interaction.
 *
 * Since states are driven by JavaScript only, it is important to understand
 * that all states are applied on presentation only, none of the states force
 * any server-side logic, and that they will not be applied for site visitors
 * without JavaScript support. All modules implementing states have to make
 * sure that the intended logic also works without JavaScript being enabled.
 *
 * #states is an associative array in the form of:
 * @code
 * array(
 *   STATE1 => CONDITIONS_ARRAY1,
 *   STATE2 => CONDITIONS_ARRAY2,
 *   ...
 * )
 * @endcode
 * Each key is the name of a state to apply to the element, such as 'visible'.
 * Each value is a list of conditions that denote when the state should be
 * applied.
 *
 * Multiple different states may be specified to act on complex conditions:
 * @code
 * array(
 *   'visible' => CONDITIONS,
 *   'checked' => OTHER_CONDITIONS,
 * )
 * @endcode
 *
 * Every condition is a key/value pair, whose key is a jQuery selector that
 * denotes another element on the page, and whose value is an array of
 * conditions, which must bet met on that element:
 * @code
 * array(
 *   'visible' => array(
 *     JQUERY_SELECTOR => REMOTE_CONDITIONS,
 *     JQUERY_SELECTOR => REMOTE_CONDITIONS,
 *     ...
 *   ),
 * )
 * @endcode
 * All conditions must be met for the state to be applied.
 *
 * Each remote condition is a key/value pair specifying conditions on the other
 * element that need to be met to apply the state to the element:
 * @code
 * array(
 *   'visible' => array(
 *     ':input[name="remote_checkbox"]' => array('checked' => TRUE),
 *   ),
 * )
 * @endcode
 *
 * For example, to show a textfield only when a checkbox is checked:
 * @code
 * $form['toggle_me'] = array(
 *   '#type' => 'checkbox',
 *   '#title' => t('Tick this box to type'),
 * );
 * $form['settings'] = array(
 *   '#type' => 'textfield',
 *   '#states' => array(
 *     // Only show this field when the 'toggle_me' checkbox is enabled.
 *     'visible' => array(
 *       ':input[name="toggle_me"]' => array('checked' => TRUE),
 *     ),
 *   ),
 * );
 * @endcode
 *
 * The following states may be applied to an element:
 * - enabled
 * - disabled
 * - required
 * - optional
 * - visible
 * - invisible
 * - checked
 * - unchecked
 * - expanded
 * - collapsed
 *
 * The following states may be used in remote conditions:
 * - empty
 * - filled
 * - checked
 * - unchecked
 * - expanded
 * - collapsed
 * - value
 *
 * The following states exist for both elements and remote conditions, but are
 * not fully implemented and may not change anything on the element:
 * - relevant
 * - irrelevant
 * - valid
 * - invalid
 * - touched
 * - untouched
 * - readwrite
 * - readonly
 *
 * When referencing select lists and radio buttons in remote conditions, a
 * 'value' condition must be used:
 * @code
 *   '#states' => array(
 *     // Show the settings if 'bar' has been selected for 'foo'.
 *     'visible' => array(
 *       ':input[name="foo"]' => array('value' => 'bar'),
 *     ),
 *   ),
 * @endcode
 *
 * @param $elements
 *   A renderable array element having a #states property as described above.
 *
 * @see form_example_states_form()
 */
function drupal_process_states(&$elements) {
  $elements['#attached']['library'][] = array('system', 'drupal.states');
  $elements['#attached']['js'][] = array(
    'type' => 'setting',
    'data' => array('states' => array('#' . $elements['#id'] => $elements['#states'])),
  );
}

/**
 * Adds multiple JavaScript or CSS files at the same time.
 *
 * A library defines a set of JavaScript and/or CSS files, optionally using
 * settings, and optionally requiring another library. For example, a library
 * can be a jQuery plugin, a JavaScript framework, or a CSS framework. This
 * function allows modules to load a library defined/shipped by itself or a
 * depending module, without having to add all files of the library separately.
 * Each library is only loaded once.
 *
 * @param $module
 *   The name of the module that registered the library.
 * @param $name
 *   The name of the library to add.
 * @param $every_page
 *   Set to TRUE if this library is added to every page on the site. Only items
 *   with the every_page flag set to TRUE can participate in aggregation.
 *
 * @return
 *   TRUE if the library was successfully added; FALSE if the library or one of
 *   its dependencies could not be added.
 *
 * @see drupal_get_library()
 * @see hook_library()
 * @see hook_library_alter()
 */
function drupal_add_library($module, $name, $every_page = NULL) {
  $added = &drupal_static(__FUNCTION__, array());

  // Only process the library if it exists and it was not added already.
  if (!isset($added[$module][$name])) {
    if ($library = drupal_get_library($module, $name)) {
      // Add all components within the library.
      $elements['#attached'] = array(
        'library' => $library['dependencies'],
        'js' => $library['js'],
        'css' => $library['css'],
      );
      $added[$module][$name] = drupal_process_attached($elements, JS_LIBRARY, TRUE, $every_page);
    }
    else {
      // Requested library does not exist.
      $added[$module][$name] = FALSE;
    }
  }

  return $added[$module][$name];
}

/**
 * Retrieves information for a JavaScript/CSS library.
 *
 * Library information is statically cached. Libraries are keyed by module for
 * several reasons:
 * - Libraries are not unique. Multiple modules might ship with the same library
 *   in a different version or variant. This registry cannot (and does not
 *   attempt to) prevent library conflicts.
 * - Modules implementing and thereby depending on a library that is registered
 *   by another module can only rely on that module's library.
 * - Two (or more) modules can still register the same library and use it
 *   without conflicts in case the libraries are loaded on certain pages only.
 *
 * @param $module
 *   The name of a module that registered a library.
 * @param $name
 *   (optional) The name of a registered library to retrieve. By default, all
 *   libraries registered by $module are returned.
 *
 * @return
 *   The definition of the requested library, if $name was passed and it exists,
 *   or FALSE if it does not exist. If no $name was passed, an associative array
 *   of libraries registered by $module is returned (which may be empty).
 *
 * @see drupal_add_library()
 * @see hook_library()
 * @see hook_library_alter()
 *
 * @todo The purpose of drupal_get_*() is completely different to other page
 *   requisite API functions; find and use a different name.
 */
function drupal_get_library($module, $name = NULL) {
  $libraries = &drupal_static(__FUNCTION__, array());

  if (!isset($libraries[$module])) {
    // Retrieve all libraries associated with the module.
    $module_libraries = module_invoke($module, 'library');
    if (empty($module_libraries)) {
      $module_libraries = array();
    }
    // Allow modules to alter the module's registered libraries.
    drupal_alter('library', $module_libraries, $module);

    foreach ($module_libraries as $key => $data) {
      if (is_array($data)) {
        // Add default elements to allow for easier processing.
        $module_libraries[$key] += array('dependencies' => array(), 'js' => array(), 'css' => array());
        foreach ($module_libraries[$key]['js'] as $file => $options) {
          $module_libraries[$key]['js'][$file]['version'] = $module_libraries[$key]['version'];
        }
      }
    }
    $libraries[$module] = $module_libraries;
  }
  if (isset($name)) {
    if (!isset($libraries[$module][$name])) {
      $libraries[$module][$name] = FALSE;
    }
    return $libraries[$module][$name];
  }
  return $libraries[$module];
}

/**
 * Assists in adding the tableDrag JavaScript behavior to a themed table.
 *
 * Draggable tables should be used wherever an outline or list of sortable items
 * needs to be arranged by an end-user. Draggable tables are very flexible and
 * can manipulate the value of form elements placed within individual columns.
 *
 * To set up a table to use drag and drop in place of weight select-lists or in
 * place of a form that contains parent relationships, the form must be themed
 * into a table. The table must have an ID attribute set. If using
 * theme_table(), the ID may be set as follows:
 * @code
 * $output = theme('table', array('header' => $header, 'rows' => $rows, 'attributes' => array('id' => 'my-module-table')));
 * return $output;
 * @endcode
 *
 * In the theme function for the form, a special class must be added to each
 * form element within the same column, "grouping" them together.
 *
 * In a situation where a single weight column is being sorted in the table, the
 * classes could be added like this (in the theme function):
 * @code
 * $form['my_elements'][$delta]['weight']['#attributes']['class'] = array('my-elements-weight');
 * @endcode
 *
 * Each row of the table must also have a class of "draggable" in order to
 * enable the drag handles:
 * @code
 * $row = array(...);
 * $rows[] = array(
 *   'data' => $row,
 *   'class' => array('draggable'),
 * );
 * @endcode
 *
 * When tree relationships are present, the two additional classes
 * 'tabledrag-leaf' and 'tabledrag-root' can be used to refine the behavior:
 * - Rows with the 'tabledrag-leaf' class cannot have child rows.
 * - Rows with the 'tabledrag-root' class cannot be nested under a parent row.
 *
 * Calling drupal_add_tabledrag() would then be written as such:
 * @code
 * drupal_add_tabledrag('my-module-table', 'order', 'sibling', 'my-elements-weight');
 * @endcode
 *
 * In a more complex case where there are several groups in one column (such as
 * the block regions on the admin/structure/block page), a separate subgroup
 * class must also be added to differentiate the groups.
 * @code
 * $form['my_elements'][$region][$delta]['weight']['#attributes']['class'] = array('my-elements-weight', 'my-elements-weight-' . $region);
 * @endcode
 *
 * $group is still 'my-element-weight', and the additional $subgroup variable
 * will be passed in as 'my-elements-weight-' . $region. This also means that
 * you'll need to call drupal_add_tabledrag() once for every region added.
 *
 * @code
 * foreach ($regions as $region) {
 *   drupal_add_tabledrag('my-module-table', 'order', 'sibling', 'my-elements-weight', 'my-elements-weight-' . $region);
 * }
 * @endcode
 *
 * In a situation where tree relationships are present, adding multiple
 * subgroups is not necessary, because the table will contain indentations that
 * provide enough information about the sibling and parent relationships. See
 * theme_menu_overview_form() for an example creating a table containing parent
 * relationships.
 *
 * Note that this function should be called from the theme layer, such as in a
 * .tpl.php file, theme_ function, or in a template_preprocess function, not in
 * a form declaration. Though the same JavaScript could be added to the page
 * using drupal_add_js() directly, this function helps keep template files
 * clean and readable. It also prevents tabledrag.js from being added twice
 * accidentally.
 *
 * @param $table_id
 *   String containing the target table's id attribute. If the table does not
 *   have an id, one will need to be set, such as <table id="my-module-table">.
 * @param $action
 *   String describing the action to be done on the form item. Either 'match'
 *   'depth', or 'order'. Match is typically used for parent relationships.
 *   Order is typically used to set weights on other form elements with the same
 *   group. Depth updates the target element with the current indentation.
 * @param $relationship
 *   String describing where the $action variable should be performed. Either
 *   'parent', 'sibling', 'group', or 'self'. Parent will only look for fields
 *   up the tree. Sibling will look for fields in the same group in rows above
 *   and below it. Self affects the dragged row itself. Group affects the
 *   dragged row, plus any children below it (the entire dragged group).
 * @param $group
 *   A class name applied on all related form elements for this action.
 * @param $subgroup
 *   (optional) If the group has several subgroups within it, this string should
 *   contain the class name identifying fields in the same subgroup.
 * @param $source
 *   (optional) If the $action is 'match', this string should contain the class
 *   name identifying what field will be used as the source value when matching
 *   the value in $subgroup.
 * @param $hidden
 *   (optional) The column containing the field elements may be entirely hidden
 *   from view dynamically when the JavaScript is loaded. Set to FALSE if the
 *   column should not be hidden.
 * @param $limit
 *   (optional) Limit the maximum amount of parenting in this table.
 * @see block-admin-display-form.tpl.php
 * @see theme_menu_overview_form()
 */
function drupal_add_tabledrag($table_id, $action, $relationship, $group, $subgroup = NULL, $source = NULL, $hidden = TRUE, $limit = 0) {
  $js_added = &drupal_static(__FUNCTION__, FALSE);
  if (!$js_added) {
    // Add the table drag JavaScript to the page before the module JavaScript
    // to ensure that table drag behaviors are registered before any module
    // uses it.
    drupal_add_library('system', 'jquery.cookie');
    drupal_add_js('misc/tabledrag.js', array('weight' => -1));
    $js_added = TRUE;
  }

  // If a subgroup or source isn't set, assume it is the same as the group.
  $target = isset($subgroup) ? $subgroup : $group;
  $source = isset($source) ? $source : $target;
  $settings['tableDrag'][$table_id][$group][] = array(
    'target' => $target,
    'source' => $source,
    'relationship' => $relationship,
    'action' => $action,
    'hidden' => $hidden,
    'limit' => $limit,
  );
  drupal_add_js($settings, 'setting');
}

/**
 * Aggregates JavaScript files into a cache file in the files directory.
 *
 * The file name for the JavaScript cache file is generated from the hash of
 * the aggregated contents of the files in $files. This forces proxies and
 * browsers to download new JavaScript when the JavaScript changes.
 *
 * The cache file name is retrieved on a page load via a lookup variable that
 * contains an associative array. The array key is the hash of the names in
 * $files while the value is the cache file name. The cache file is generated
 * in two cases. First, if there is no file name value for the key, which will
 * happen if a new file name has been added to $files or after the lookup
 * variable is emptied to force a rebuild of the cache. Second, the cache file
 * is generated if it is missing on disk. Old cache files are not deleted
 * immediately when the lookup variable is emptied, but are deleted after a set
 * period by drupal_delete_file_if_stale(). This ensures that files referenced
 * by a cached page will still be available.
 *
 * @param $files
 *   An array of JavaScript files to aggregate and compress into one file.
 *
 * @return
 *   The URI of the cache file, or FALSE if the file could not be saved.
 */
function drupal_build_js_cache($files) {
  $contents = '';
  $uri = '';
  $map = variable_get('drupal_js_cache_files', array());
  // Create a new array so that only the file names are used to create the hash.
  // This prevents new aggregates from being created unnecessarily.
  $js_data = array();
  foreach ($files as $file) {
    $js_data[] = $file['data'];
  }
  $key = hash('sha256', serialize($js_data));
  if (isset($map[$key])) {
    $uri = $map[$key];
  }

  if (empty($uri) || !file_exists($uri)) {
    // Build aggregate JS file.
    foreach ($files as $path => $info) {
      if ($info['preprocess']) {
        // Append a ';' and a newline after each JS file to prevent them from running together.
        $contents .= file_get_contents($path) . ";\n";
      }
    }
    // Prefix filename to prevent blocking by firewalls which reject files
    // starting with "ad*".
    $filename = 'js_' . drupal_hash_base64($contents) . '.js';
    // Create the js/ within the files folder.
    $jspath = 'public://js';
    $uri = $jspath . '/' . $filename;
    // Create the JS file.
    file_prepare_directory($jspath, FILE_CREATE_DIRECTORY);
    if (!file_exists($uri) && !file_unmanaged_save_data($contents, $uri, FILE_EXISTS_REPLACE)) {
      return FALSE;
    }
    // If JS gzip compression is enabled, clean URLs are enabled (which means
    // that rewrite rules are working) and the zlib extension is available then
    // create a gzipped version of this file. This file is served conditionally
    // to browsers that accept gzip using .htaccess rules.
    if (variable_get('js_gzip_compression', TRUE) && variable_get('clean_url', 0) && extension_loaded('zlib')) {
      if (!file_exists($uri . '.gz') && !file_unmanaged_save_data(gzencode($contents, 9, FORCE_GZIP), $uri . '.gz', FILE_EXISTS_REPLACE)) {
        return FALSE;
      }
    }
    $map[$key] = $uri;
    variable_set('drupal_js_cache_files', $map);
  }
  return $uri;
}

/**
 * Deletes old cached JavaScript files and variables.
 */
function drupal_clear_js_cache() {
  variable_del('javascript_parsed');
  variable_del('drupal_js_cache_files');
  file_scan_directory('public://js', '/.*/', array('callback' => 'drupal_delete_file_if_stale'));
}

/**
 * Converts a PHP variable into its JavaScript equivalent.
 *
 * We use HTML-safe strings, with several characters escaped.
 *
 * @see drupal_json_decode()
 * @see drupal_json_encode_helper()
 * @ingroup php_wrappers
 */
function drupal_json_encode($var) {
  // The PHP version cannot change within a request.
  static $php530;

  if (!isset($php530)) {
    $php530 = version_compare(PHP_VERSION, '5.3.0', '>=');
  }

  if ($php530) {
    // Encode <, >, ', &, and " using the json_encode() options parameter.
    return json_encode($var, JSON_HEX_TAG | JSON_HEX_APOS | JSON_HEX_AMP | JSON_HEX_QUOT);
  }

  // json_encode() escapes <, >, ', &, and " using its options parameter, but
  // does not support this parameter prior to PHP 5.3.0.  Use a helper instead.
  include_once DRUPAL_ROOT . '/includes/json-encode.inc';
  return drupal_json_encode_helper($var);
}

/**
 * Converts an HTML-safe JSON string into its PHP equivalent.
 *
 * @see drupal_json_encode()
 * @ingroup php_wrappers
 */
function drupal_json_decode($var) {
  return json_decode($var, TRUE);
}

/**
 * Returns data in JSON format.
 *
 * This function should be used for JavaScript callback functions returning
 * data in JSON format. It sets the header for JavaScript output.
 *
 * @param $var
 *   (optional) If set, the variable will be converted to JSON and output.
 */
function drupal_json_output($var = NULL) {
  // We are returning JSON, so tell the browser.
  drupal_add_http_header('Content-Type', 'application/json');

  if (isset($var)) {
    echo drupal_json_encode($var);
  }
}

/**
 * Ensures the private key variable used to generate tokens is set.
 *
 * @return
 *   The private key.
 */
function drupal_get_private_key() {
  if (!($key = variable_get('drupal_private_key', 0))) {
    $key = drupal_random_key();
    variable_set('drupal_private_key', $key);
  }
  return $key;
}

/**
 * Generates a token based on $value, the user session, and the private key.
 *
 * @param $value
 *   An additional value to base the token on.
 *
 * The generated token is based on the session ID of the current user. Normally,
 * anonymous users do not have a session, so the generated token will be
 * different on every page request. To generate a token for users without a
 * session, manually start a session prior to calling this function.
 *
 * @return string
 *   A 43-character URL-safe token for validation, based on the user session ID,
 *   the hash salt provided from drupal_get_hash_salt(), and the
 *   'drupal_private_key' configuration variable.
 *
 * @see drupal_get_hash_salt()
 */
function drupal_get_token($value = '') {
  return drupal_hmac_base64($value, session_id() . drupal_get_private_key() . drupal_get_hash_salt());
}

/**
 * Validates a token based on $value, the user session, and the private key.
 *
 * @param $token
 *   The token to be validated.
 * @param $value
 *   An additional value to base the token on.
 * @param $skip_anonymous
 *   Set to true to skip token validation for anonymous users.
 *
 * @return
 *   True for a valid token, false for an invalid token. When $skip_anonymous
 *   is true, the return value will always be true for anonymous users.
 */
function drupal_valid_token($token, $value = '', $skip_anonymous = FALSE) {
  global $user;
  return (($skip_anonymous && $user->uid == 0) || ($token === drupal_get_token($value)));
}

function _drupal_bootstrap_full() {
  static $called = FALSE;

  if ($called) {
    return;
  }
  $called = TRUE;
  require_once DRUPAL_ROOT . '/' . variable_get('path_inc', 'includes/path.inc');
  require_once DRUPAL_ROOT . '/includes/theme.inc';
  require_once DRUPAL_ROOT . '/includes/pager.inc';
  require_once DRUPAL_ROOT . '/' . variable_get('menu_inc', 'includes/menu.inc');
  require_once DRUPAL_ROOT . '/includes/tablesort.inc';
  require_once DRUPAL_ROOT . '/includes/file.inc';
  require_once DRUPAL_ROOT . '/includes/unicode.inc';
  require_once DRUPAL_ROOT . '/includes/image.inc';
  require_once DRUPAL_ROOT . '/includes/form.inc';
  require_once DRUPAL_ROOT . '/includes/mail.inc';
  require_once DRUPAL_ROOT . '/includes/actions.inc';
  require_once DRUPAL_ROOT . '/includes/ajax.inc';
  require_once DRUPAL_ROOT . '/includes/token.inc';
  require_once DRUPAL_ROOT . '/includes/errors.inc';

  // Detect string handling method
  unicode_check();
  // Undo magic quotes
  fix_gpc_magic();
  // Load all enabled modules
  module_load_all();
  // Make sure all stream wrappers are registered.
  file_get_stream_wrappers();
  // Ensure mt_rand is reseeded, to prevent random values from one page load
  // being exploited to predict random values in subsequent page loads.
  $seed = unpack("L", drupal_random_bytes(4));
  mt_srand($seed[1]);

  $test_info = &$GLOBALS['drupal_test_info'];
  if (!empty($test_info['in_child_site'])) {
    // Running inside the simpletest child site, log fatal errors to test
    // specific file directory.
    ini_set('log_errors', 1);
    ini_set('error_log', 'public://error.log');
  }

  // Initialize $_GET['q'] prior to invoking hook_init().
  drupal_path_initialize();

  // Let all modules take action before the menu system handles the request.
  // We do not want this while running update.php.
  if (!defined('MAINTENANCE_MODE') || MAINTENANCE_MODE != 'update') {
    // Prior to invoking hook_init(), initialize the theme (potentially a custom
    // one for this page), so that:
    // - Modules with hook_init() implementations that call theme() or
    //   theme_get_registry() don't initialize the incorrect theme.
    // - The theme can have hook_*_alter() implementations affect page building
    //   (e.g., hook_form_alter(), hook_node_view_alter(), hook_page_alter()),
    //   ahead of when rendering starts.
    menu_set_custom_theme();
    drupal_theme_initialize();
    module_invoke_all('init');
  }
}

/**
 * Stores the current page in the cache.
 *
 * If page_compression is enabled, a gzipped version of the page is stored in
 * the cache to avoid compressing the output on each request. The cache entry
 * is unzipped in the relatively rare event that the page is requested by a
 * client without gzip support.
 *
 * Page compression requires the PHP zlib extension
 * (http://php.net/manual/ref.zlib.php).
 *
 * @see drupal_page_header()
 */
function drupal_page_set_cache() {
  global $base_root;

  if (drupal_page_is_cacheable()) {

    // Check whether the current page might be compressed.
    $page_compressed = variable_get('page_compression', TRUE) && extension_loaded('zlib');

    $cache = (object) array(
      'cid' => $base_root . request_uri(),
      'data' => array(
        'path' => $_GET['q'],
        'body' => ob_get_clean(),
        'title' => drupal_get_title(),
        'headers' => array(),
        // We need to store whether page was compressed or not,
        // because by the time it is read, the configuration might change.
        'page_compressed' => $page_compressed,
      ),
      'expire' => CACHE_TEMPORARY,
      'created' => REQUEST_TIME,
    );

    // Restore preferred header names based on the lower-case names returned
    // by drupal_get_http_header().
    $header_names = _drupal_set_preferred_header_name();
    foreach (drupal_get_http_header() as $name_lower => $value) {
      $cache->data['headers'][$header_names[$name_lower]] = $value;
      if ($name_lower == 'expires') {
        // Use the actual timestamp from an Expires header if available.
        $cache->expire = strtotime($value);
      }
    }

    if ($cache->data['body']) {
      if ($page_compressed) {
        $cache->data['body'] = gzencode($cache->data['body'], 9, FORCE_GZIP);
      }
      cache_set($cache->cid, $cache->data, 'cache_page', $cache->expire);
    }
    return $cache;
  }
}

/**
 * Executes a cron run when called.
 *
 * Do not call this function from a test. Use $this->cronRun() instead.
 *
 * @return
 *   TRUE if cron ran successfully.
 */
function drupal_cron_run() {
  // Allow execution to continue even if the request gets canceled.
  @ignore_user_abort(TRUE);

  // Prevent session information from being saved while cron is running.
  $original_session_saving = drupal_save_session();
  drupal_save_session(FALSE);

  // Force the current user to anonymous to ensure consistent permissions on
  // cron runs.
  $original_user = $GLOBALS['user'];
  $GLOBALS['user'] = drupal_anonymous_user();

  // Try to allocate enough time to run all the hook_cron implementations.
  drupal_set_time_limit(240);

  $return = FALSE;
  // Grab the defined cron queues.
  $queues = module_invoke_all('cron_queue_info');
  drupal_alter('cron_queue_info', $queues);

  // Try to acquire cron lock.
  if (!lock_acquire('cron', 240.0)) {
    // Cron is still running normally.
    watchdog('cron', 'Attempting to re-run cron while it is already running.', array(), WATCHDOG_WARNING);
  }
  else {
    // Make sure every queue exists. There is no harm in trying to recreate an
    // existing queue.
    foreach ($queues as $queue_name => $info) {
      DrupalQueue::get($queue_name)->createQueue();
    }

    // Iterate through the modules calling their cron handlers (if any):
    foreach (module_implements('cron') as $module) {
      // Do not let an exception thrown by one module disturb another.
      try {
        module_invoke($module, 'cron');
      }
      catch (Exception $e) {
        watchdog_exception('cron', $e);
      }
    }

    // Record cron time.
    variable_set('cron_last', REQUEST_TIME);
    watchdog('cron', 'Cron run completed.', array(), WATCHDOG_NOTICE);

    // Release cron lock.
    lock_release('cron');

    // Return TRUE so other functions can check if it did run successfully
    $return = TRUE;
  }

  foreach ($queues as $queue_name => $info) {
    if (!empty($info['skip on cron'])) {
      // Do not run if queue wants to skip.
      continue;
    }
    $function = $info['worker callback'];
    $end = time() + (isset($info['time']) ? $info['time'] : 15);
    $queue = DrupalQueue::get($queue_name);
    while (time() < $end && ($item = $queue->claimItem())) {
      try {
        $function($item->data);
        $queue->deleteItem($item);
      }
      catch (Exception $e) {
        // In case of exception log it and leave the item in the queue
        // to be processed again later.
        watchdog_exception('cron', $e);
      }
    }
  }
  // Restore the user.
  $GLOBALS['user'] = $original_user;
  drupal_save_session($original_session_saving);

  return $return;
}

/**
 * DEPRECATED: Shutdown function: Performs cron cleanup.
 *
 * This function is deprecated because the 'cron_semaphore' variable it
 * references no longer exists. It is therefore no longer used as a shutdown
 * function by Drupal core.
 *
 * @deprecated
 */
function drupal_cron_cleanup() {
  // See if the semaphore is still locked.
  if (variable_get('cron_semaphore', FALSE)) {
    watchdog('cron', 'Cron run exceeded the time limit and was aborted.', array(), WATCHDOG_WARNING);

    // Release cron semaphore.
    variable_del('cron_semaphore');
  }
}

/**
 * Returns information about system object files (modules, themes, etc.).
 *
 * This function is used to find all or some system object files (module files,
 * theme files, etc.) that exist on the site. It searches in several locations,
 * depending on what type of object you are looking for. For instance, if you
 * are looking for modules and call:
 * @code
 * drupal_system_listing("/\.module$/", "modules", 'name', 0);
 * @endcode
 * this function will search the site-wide modules directory (i.e., /modules/),
 * your installation profile's directory (i.e.,
 * /profiles/your_site_profile/modules/), the all-sites directory (i.e.,
 * /sites/all/modules/), and your site-specific directory (i.e.,
 * /sites/your_site_dir/modules/), in that order, and return information about
 * all of the files ending in .module in those directories.
 *
 * The information is returned in an associative array, which can be keyed on
 * the file name ($key = 'filename'), the file name without the extension ($key
 * = 'name'), or the full file stream URI ($key = 'uri'). If you use a key of
 * 'filename' or 'name', files found later in the search will take precedence
 * over files found earlier (unless they belong to a module or theme not
 * compatible with Drupal core); if you choose a key of 'uri', you will get all
 * files found.
 *
 * @param string $mask
 *   The preg_match() regular expression for the files to find.
 * @param string $directory
 *   The subdirectory name in which the files are found. For example,
 *   'modules' will search in sub-directories of the top-level /modules
 *   directory, sub-directories of /sites/all/modules/, etc.
 * @param string $key
 *   The key to be used for the associative array returned. Possible values are
 *   'uri', for the file's URI; 'filename', for the basename of the file; and
 *   'name' for the name of the file without the extension. If you choose 'name'
 *   or 'filename', only the highest-precedence file will be returned.
 * @param int $min_depth
 *   Minimum depth of directories to return files from, relative to each
 *   directory searched. For instance, a minimum depth of 2 would find modules
 *   inside /modules/node/tests, but not modules directly in /modules/node.
 *
 * @return array
 *   An associative array of file objects, keyed on the chosen key. Each element
 *   in the array is an object containing file information, with properties:
 *   - 'uri': Full URI of the file.
 *   - 'filename': File name.
 *   - 'name': Name of file without the extension.
 */
function drupal_system_listing($mask, $directory, $key = 'name', $min_depth = 1) {
  $config = conf_path();

  $searchdir = array($directory);
  $files = array();

  // The 'profiles' directory contains pristine collections of modules and
  // themes as organized by a distribution. It is pristine in the same way
  // that /modules is pristine for core; users should avoid changing anything
  // there in favor of sites/all or sites/<domain> directories.
  $profiles = array();
  $profile = drupal_get_profile();
  // For SimpleTest to be able to test modules packaged together with a
  // distribution we need to include the profile of the parent site (in which
  // test runs are triggered).
  if (drupal_valid_test_ua()) {
    $testing_profile = variable_get('simpletest_parent_profile', FALSE);
    if ($testing_profile && $testing_profile != $profile) {
      $profiles[] = $testing_profile;
    }
  }
  // In case both profile directories contain the same extension, the actual
  // profile always has precedence.
  $profiles[] = $profile;
  foreach ($profiles as $profile) {
    if (file_exists("profiles/$profile/$directory")) {
      $searchdir[] = "profiles/$profile/$directory";
    }
  }

  // Always search sites/all/* as well as the global directories.
  $searchdir[] = 'sites/all/' . $directory;

  if (file_exists("$config/$directory")) {
    $searchdir[] = "$config/$directory";
  }

  // Get current list of items.
  if (!function_exists('file_scan_directory')) {
    require_once DRUPAL_ROOT . '/includes/file.inc';
  }
  foreach ($searchdir as $dir) {
    $files_to_add = file_scan_directory($dir, $mask, array('key' => $key, 'min_depth' => $min_depth));

    // Duplicate files found in later search directories take precedence over
    // earlier ones, so we want them to overwrite keys in our resulting
    // $files array.
    // The exception to this is if the later file is from a module or theme not
    // compatible with Drupal core. This may occur during upgrades of Drupal
    // core when new modules exist in core while older contrib modules with the
    // same name exist in a directory such as sites/all/modules/.
    foreach (array_intersect_key($files_to_add, $files) as $file_key => $file) {
      // If it has no info file, then we just behave liberally and accept the
      // new resource on the list for merging.
      if (file_exists($info_file = dirname($file->uri) . '/' . $file->name . '.info')) {
        // Get the .info file for the module or theme this file belongs to.
        $info = drupal_parse_info_file($info_file);

        // If the module or theme is incompatible with Drupal core, remove it
        // from the array for the current search directory, so it is not
        // overwritten when merged with the $files array.
        if (isset($info['core']) && $info['core'] != DRUPAL_CORE_COMPATIBILITY) {
          unset($files_to_add[$file_key]);
        }
      }
    }
    $files = array_merge($files, $files_to_add);
  }

  return $files;
}

/**
 * Sets the main page content value for later use.
 *
 * Given the nature of the Drupal page handling, this will be called once with
 * a string or array. We store that and return it later as the block is being
 * displayed.
 *
 * @param $content
 *   A string or renderable array representing the body of the page.
 *
 * @return
 *   If called without $content, a renderable array representing the body of
 *   the page.
 */
function drupal_set_page_content($content = NULL) {
  $content_block = &drupal_static(__FUNCTION__, NULL);
  $main_content_display = &drupal_static('system_main_content_added', FALSE);

  if (!empty($content)) {
    $content_block = (is_array($content) ? $content : array('main' => array('#markup' => $content)));
  }
  else {
    // Indicate that the main content has been requested. We assume that
    // the module requesting the content will be adding it to the page.
    // A module can indicate that it does not handle the content by setting
    // the static variable back to FALSE after calling this function.
    $main_content_display = TRUE;
    return $content_block;
  }
}

/**
 * #pre_render callback to render #browsers into #prefix and #suffix.
 *
 * @param $elements
 *   A render array with a '#browsers' property. The '#browsers' property can
 *   contain any or all of the following keys:
 *   - 'IE': If FALSE, the element is not rendered by Internet Explorer. If
 *     TRUE, the element is rendered by Internet Explorer. Can also be a string
 *     containing an expression for Internet Explorer to evaluate as part of a
 *     conditional comment. For example, this can be set to 'lt IE 7' for the
 *     element to be rendered in Internet Explorer 6, but not in Internet
 *     Explorer 7 or higher. Defaults to TRUE.
 *   - '!IE': If FALSE, the element is not rendered by browsers other than
 *     Internet Explorer. If TRUE, the element is rendered by those browsers.
 *     Defaults to TRUE.
 *   Examples:
 *   - To render an element in all browsers, '#browsers' can be left out or set
 *     to array('IE' => TRUE, '!IE' => TRUE).
 *   - To render an element in Internet Explorer only, '#browsers' can be set
 *     to array('!IE' => FALSE).
 *   - To render an element in Internet Explorer 6 only, '#browsers' can be set
 *     to array('IE' => 'lt IE 7', '!IE' => FALSE).
 *   - To render an element in Internet Explorer 8 and higher and in all other
 *     browsers, '#browsers' can be set to array('IE' => 'gte IE 8').
 *
 * @return
 *   The passed-in element with markup for conditional comments potentially
 *   added to '#prefix' and '#suffix'.
 */
function drupal_pre_render_conditional_comments($elements) {
  $browsers = isset($elements['#browsers']) ? $elements['#browsers'] : array();
  $browsers += array(
    'IE' => TRUE,
    '!IE' => TRUE,
  );

  // If rendering in all browsers, no need for conditional comments.
  if ($browsers['IE'] === TRUE && $browsers['!IE']) {
    return $elements;
  }

  // Determine the conditional comment expression for Internet Explorer to
  // evaluate.
  if ($browsers['IE'] === TRUE) {
    $expression = 'IE';
  }
  elseif ($browsers['IE'] === FALSE) {
    $expression = '!IE';
  }
  else {
    $expression = $browsers['IE'];
  }

  // Wrap the element's potentially existing #prefix and #suffix properties with
  // conditional comment markup. The conditional comment expression is evaluated
  // by Internet Explorer only. To control the rendering by other browsers,
  // either the "downlevel-hidden" or "downlevel-revealed" technique must be
  // used. See http://en.wikipedia.org/wiki/Conditional_comment for details.
  $elements += array(
    '#prefix' => '',
    '#suffix' => '',
  );
  if (!$browsers['!IE']) {
    // "downlevel-hidden".
    $elements['#prefix'] = "\n<!--[if $expression]>\n" . $elements['#prefix'];
    $elements['#suffix'] .= "<![endif]-->\n";
  }
  else {
    // "downlevel-revealed".
    $elements['#prefix'] = "\n<!--[if $expression]><!-->\n" . $elements['#prefix'];
    $elements['#suffix'] .= "<!--<![endif]-->\n";
  }

  return $elements;
}

/**
 * #pre_render callback to render a link into #markup.
 *
 * Doing so during pre_render gives modules a chance to alter the link parts.
 *
 * @param $elements
 *   A structured array whose keys form the arguments to l():
 *   - #title: The link text to pass as argument to l().
 *   - #href: The URL path component to pass as argument to l().
 *   - #options: (optional) An array of options to pass to l().
 *
 * @return
 *   The passed-in elements containing a rendered link in '#markup'.
 */
function drupal_pre_render_link($element) {
  // By default, link options to pass to l() are normally set in #options.
  $element += array('#options' => array());
  // However, within the scope of renderable elements, #attributes is a valid
  // way to specify attributes, too. Take them into account, but do not override
  // attributes from #options.
  if (isset($element['#attributes'])) {
    $element['#options'] += array('attributes' => array());
    $element['#options']['attributes'] += $element['#attributes'];
  }

  // This #pre_render callback can be invoked from inside or outside of a Form
  // API context, and depending on that, a HTML ID may be already set in
  // different locations. #options should have precedence over Form API's #id.
  // #attributes have been taken over into #options above already.
  if (isset($element['#options']['attributes']['id'])) {
    $element['#id'] = $element['#options']['attributes']['id'];
  }
  elseif (isset($element['#id'])) {
    $element['#options']['attributes']['id'] = $element['#id'];
  }

  // Conditionally invoke ajax_pre_render_element(), if #ajax is set.
  if (isset($element['#ajax']) && !isset($element['#ajax_processed'])) {
    // If no HTML ID was found above, automatically create one.
    if (!isset($element['#id'])) {
      $element['#id'] = $element['#options']['attributes']['id'] = drupal_html_id('ajax-link');
    }
    // If #ajax['path] was not specified, use the href as Ajax request URL.
    if (!isset($element['#ajax']['path'])) {
      $element['#ajax']['path'] = $element['#href'];
      $element['#ajax']['options'] = $element['#options'];
    }
    $element = ajax_pre_render_element($element);
  }

  $element['#markup'] = l($element['#title'], $element['#href'], $element['#options']);
  return $element;
}

/**
 * #pre_render callback that collects child links into a single array.
 *
 * This function can be added as a pre_render callback for a renderable array,
 * usually one which will be themed by theme_links(). It iterates through all
 * unrendered children of the element, collects any #links properties it finds,
 * merges them into the parent element's #links array, and prevents those
 * children from being rendered separately.
 *
 * The purpose of this is to allow links to be logically grouped into related
 * categories, so that each child group can be rendered as its own list of
 * links if drupal_render() is called on it, but calling drupal_render() on the
 * parent element will still produce a single list containing all the remaining
 * links, regardless of what group they were in.
 *
 * A typical example comes from node links, which are stored in a renderable
 * array similar to this:
 * @code
 * $node->content['links'] = array(
 *   '#theme' => 'links__node',
 *   '#pre_render' => array('drupal_pre_render_links'),
 *   'comment' => array(
 *     '#theme' => 'links__node__comment',
 *     '#links' => array(
 *       // An array of links associated with node comments, suitable for
 *       // passing in to theme_links().
 *     ),
 *   ),
 *   'statistics' => array(
 *     '#theme' => 'links__node__statistics',
 *     '#links' => array(
 *       // An array of links associated with node statistics, suitable for
 *       // passing in to theme_links().
 *     ),
 *   ),
 *   'translation' => array(
 *     '#theme' => 'links__node__translation',
 *     '#links' => array(
 *       // An array of links associated with node translation, suitable for
 *       // passing in to theme_links().
 *     ),
 *   ),
 * );
 * @endcode
 *
 * In this example, the links are grouped by functionality, which can be
 * helpful to themers who want to display certain kinds of links independently.
 * For example, adding this code to node.tpl.php will result in the comment
 * links being rendered as a single list:
 * @code
 * print render($content['links']['comment']);
 * @endcode
 *
 * (where $node->content has been transformed into $content before handing
 * control to the node.tpl.php template).
 *
 * The pre_render function defined here allows the above flexibility, but also
 * allows the following code to be used to render all remaining links into a
 * single list, regardless of their group:
 * @code
 * print render($content['links']);
 * @endcode
 *
 * In the above example, this will result in the statistics and translation
 * links being rendered together in a single list (but not the comment links,
 * which were rendered previously on their own).
 *
 * Because of the way this function works, the individual properties of each
 * group (for example, a group-specific #theme property such as
 * 'links__node__comment' in the example above, or any other property such as
 * #attributes or #pre_render that is attached to it) are only used when that
 * group is rendered on its own. When the group is rendered together with other
 * children, these child-specific properties are ignored, and only the overall
 * properties of the parent are used.
 */
function drupal_pre_render_links($element) {
  $element += array('#links' => array());
  foreach (element_children($element) as $key) {
    $child = &$element[$key];
    // If the child has links which have not been printed yet and the user has
    // access to it, merge its links in to the parent.
    if (isset($child['#links']) && empty($child['#printed']) && (!isset($child['#access']) || $child['#access'])) {
      $element['#links'] += $child['#links'];
      // Mark the child as having been printed already (so that its links
      // cannot be mistakenly rendered twice).
      $child['#printed'] = TRUE;
    }
  }
  return $element;
}

/**
 * #pre_render callback to append contents in #markup to #children.
 *
 * This needs to be a #pre_render callback, because eventually assigned
 * #theme_wrappers will expect the element's rendered content in #children.
 * Note that if also a #theme is defined for the element, then the result of
 * the theme callback will override #children.
 *
 * @param $elements
 *   A structured array using the #markup key.
 *
 * @return
 *   The passed-in elements, but #markup appended to #children.
 *
 * @see drupal_render()
 */
function drupal_pre_render_markup($elements) {
  $elements['#children'] = $elements['#markup'];
  return $elements;
}

/**
 * Renders the page, including all theming.
 *
 * @param $page
 *   A string or array representing the content of a page. The array consists of
 *   the following keys:
 *   - #type: Value is always 'page'. This pushes the theming through
 *     page.tpl.php (required).
 *   - #show_messages: Suppress drupal_get_message() items. Used by Batch
 *     API (optional).
 *
 * @see hook_page_alter()
 * @see element_info()
 */
function drupal_render_page($page) {
  $main_content_display = &drupal_static('system_main_content_added', FALSE);

  // Allow menu callbacks to return strings or arbitrary arrays to render.
  // If the array returned is not of #type page directly, we need to fill
  // in the page with defaults.
  if (is_string($page) || (is_array($page) && (!isset($page['#type']) || ($page['#type'] != 'page')))) {
    drupal_set_page_content($page);
    $page = element_info('page');
  }

  // Modules can add elements to $page as needed in hook_page_build().
  foreach (module_implements('page_build') as $module) {
    $function = $module . '_page_build';
    $function($page);
  }
  // Modules alter the $page as needed. Blocks are populated into regions like
  // 'sidebar_first', 'footer', etc.
  drupal_alter('page', $page);

  // If no module has taken care of the main content, add it to the page now.
  // This allows the site to still be usable even if no modules that
  // control page regions (for example, the Block module) are enabled.
  if (!$main_content_display) {
    $page['content']['system_main'] = drupal_set_page_content();
  }

  return drupal_render($page);
}

/**
 * Renders HTML given a structured array tree.
 *
 * Recursively iterates over each of the array elements, generating HTML code.
 *
 * Renderable arrays have two kinds of key/value pairs: properties and
 * children. Properties have keys starting with '#' and their values influence
 * how the array will be rendered. Children are all elements whose keys do not
 * start with a '#'. Their values should be renderable arrays themselves,
 * which will be rendered during the rendering of the parent array. The markup
 * provided by the children is typically inserted into the markup generated by
 * the parent array.
 *
 * HTML generation for a renderable array, and the treatment of any children,
 * is controlled by two properties containing theme functions, #theme and
 * #theme_wrappers.
 *
 * #theme is the theme function called first. If it is set and the element has
 * any children, it is the responsibility of the theme function to render
 * these children. For elements that are not allowed to have any children,
 * e.g. buttons or textfields, the theme function can be used to render the
 * element itself. If #theme is not present and the element has children, each
 * child is itself rendered by a call to drupal_render(), and the results are
 * concatenated.
 *
 * The #theme_wrappers property contains an array of theme functions which will
 * be called, in order, after #theme has run. These can be used to add further
 * markup around the rendered children; e.g., fieldsets add the required markup
 * for a fieldset around their rendered child elements. All wrapper theme
 * functions have to include the element's #children property in their output,
 * as it contains the output of the previous theme functions and the rendered
 * children.
 *
 * For example, for the form element type, by default only the #theme_wrappers
 * property is set, which adds the form markup around the rendered child
 * elements of the form. This allows you to set the #theme property on a
 * specific form to a custom theme function, giving you complete control over
 * the placement of the form's children while not at all having to deal with
 * the form markup itself.
 *
 * drupal_render() can optionally cache the rendered output of elements to
 * improve performance. To use drupal_render() caching, set the element's #cache
 * property to an associative array with one or several of the following keys:
 * - 'keys': An array of one or more keys that identify the element. If 'keys'
 *   is set, the cache ID is created automatically from these keys. See
 *   drupal_render_cid_create().
 * - 'granularity' (optional): Define the cache granularity using binary
 *   combinations of the cache granularity constants, e.g.
 *   DRUPAL_CACHE_PER_USER to cache for each user separately or
 *   DRUPAL_CACHE_PER_PAGE | DRUPAL_CACHE_PER_ROLE to cache separately for each
 *   page and role. If not specified the element is cached globally for each
 *   theme and language.
 * - 'cid': Specify the cache ID directly. Either 'keys' or 'cid' is required.
 *   If 'cid' is set, 'keys' and 'granularity' are ignored. Use only if you
 *   have special requirements.
 * - 'expire': Set to one of the cache lifetime constants.
 * - 'bin': Specify a cache bin to cache the element in. Defaults to 'cache'.
 *
 * This function is usually called from within another function, like
 * drupal_get_form() or a theme function. Elements are sorted internally
 * using uasort(). Since this is expensive, when passing already sorted
 * elements to drupal_render(), for example from a database query, set
 * $elements['#sorted'] = TRUE to avoid sorting them a second time.
 *
 * drupal_render() flags each element with a '#printed' status to indicate that
 * the element has been rendered, which allows individual elements of a given
 * array to be rendered independently and prevents them from being rendered
 * more than once on subsequent calls to drupal_render() (e.g., as part of a
 * larger array). If the same array or array element is passed more than once
 * to drupal_render(), it simply returns an empty string.
 *
 * @param array $elements
 *   The structured array describing the data to be rendered.
 *
 * @return string
 *   The rendered HTML.
 */
function drupal_render(&$elements) {
  // Early-return nothing if user does not have access.
  if (empty($elements) || (isset($elements['#access']) && !$elements['#access'])) {
    return '';
  }

  // Do not print elements twice.
  if (!empty($elements['#printed'])) {
    return '';
  }

  // Try to fetch the element's markup from cache and return.
  if (isset($elements['#cache'])) {
    $cached_output = drupal_render_cache_get($elements);
    if ($cached_output !== FALSE) {
      return $cached_output;
    }
  }

  // If #markup is set, ensure #type is set. This allows to specify just #markup
  // on an element without setting #type.
  if (isset($elements['#markup']) && !isset($elements['#type'])) {
    $elements['#type'] = 'markup';
  }

  // If the default values for this element have not been loaded yet, populate
  // them.
  if (isset($elements['#type']) && empty($elements['#defaults_loaded'])) {
    $elements += element_info($elements['#type']);
  }

  // Make any final changes to the element before it is rendered. This means
  // that the $element or the children can be altered or corrected before the
  // element is rendered into the final text.
  if (isset($elements['#pre_render'])) {
    foreach ($elements['#pre_render'] as $function) {
      if (function_exists($function)) {
        $elements = $function($elements);
      }
    }
  }

  // Allow #pre_render to abort rendering.
  if (!empty($elements['#printed'])) {
    return '';
  }

  // Get the children of the element, sorted by weight.
  $children = element_children($elements, TRUE);

  // Initialize this element's #children, unless a #pre_render callback already
  // preset #children.
  if (!isset($elements['#children'])) {
    $elements['#children'] = '';
  }
  // Call the element's #theme function if it is set. Then any children of the
  // element have to be rendered there.
  if (isset($elements['#theme'])) {
    $elements['#children'] = theme($elements['#theme'], $elements);
  }
  // If #theme was not set and the element has children, render them now.
  // This is the same process as drupal_render_children() but is inlined
  // for speed.
  if ($elements['#children'] == '') {
    foreach ($children as $key) {
      $elements['#children'] .= drupal_render($elements[$key]);
    }
  }

  // Let the theme functions in #theme_wrappers add markup around the rendered
  // children.
  if (isset($elements['#theme_wrappers'])) {
    foreach ($elements['#theme_wrappers'] as $theme_wrapper) {
      $elements['#children'] = theme($theme_wrapper, $elements);
    }
  }

  // Filter the outputted content and make any last changes before the
  // content is sent to the browser. The changes are made on $content
  // which allows the output'ed text to be filtered.
  if (isset($elements['#post_render'])) {
    foreach ($elements['#post_render'] as $function) {
      if (function_exists($function)) {
        $elements['#children'] = $function($elements['#children'], $elements);
      }
    }
  }

  // Add any JavaScript state information associated with the element.
  if (!empty($elements['#states'])) {
    drupal_process_states($elements);
  }

  // Add additional libraries, CSS, JavaScript an other custom
  // attached data associated with this element.
  if (!empty($elements['#attached'])) {
    drupal_process_attached($elements);
  }

  $prefix = isset($elements['#prefix']) ? $elements['#prefix'] : '';
  $suffix = isset($elements['#suffix']) ? $elements['#suffix'] : '';
  $output = $prefix . $elements['#children'] . $suffix;

  // Cache the processed element if #cache is set.
  if (isset($elements['#cache'])) {
    drupal_render_cache_set($output, $elements);
  }

  $elements['#printed'] = TRUE;
  return $output;
}

/**
 * Renders children of an element and concatenates them.
 *
 * @param array $element
 *   The structured array whose children shall be rendered.
 * @param array $children_keys
 *   (optional) If the keys of the element's children are already known, they
 *   can be passed in to save another run of element_children().
 *
 * @return string
 *   The rendered HTML of all children of the element.

 * @see drupal_render()
 */
function drupal_render_children(&$element, $children_keys = NULL) {
  if ($children_keys === NULL) {
    $children_keys = element_children($element);
  }
  $output = '';
  foreach ($children_keys as $key) {
    if (!empty($element[$key])) {
      $output .= drupal_render($element[$key]);
    }
  }
  return $output;
}

/**
 * Renders an element.
 *
 * This function renders an element using drupal_render(). The top level
 * element is shown with show() before rendering, so it will always be rendered
 * even if hide() had been previously used on it.
 *
 * @param $element
 *   The element to be rendered.
 *
 * @return
 *   The rendered element.
 *
 * @see drupal_render()
 * @see show()
 * @see hide()
 */
function render(&$element) {
  if (is_array($element)) {
    show($element);
    return drupal_render($element);
  }
  else {
    // Safe-guard for inappropriate use of render() on flat variables: return
    // the variable as-is.
    return $element;
  }
}

/**
 * Hides an element from later rendering.
 *
 * The first time render() or drupal_render() is called on an element tree,
 * as each element in the tree is rendered, it is marked with a #printed flag
 * and the rendered children of the element are cached. Subsequent calls to
 * render() or drupal_render() will not traverse the child tree of this element
 * again: they will just use the cached children. So if you want to hide an
 * element, be sure to call hide() on the element before its parent tree is
 * rendered for the first time, as it will have no effect on subsequent
 * renderings of the parent tree.
 *
 * @param $element
 *   The element to be hidden.
 *
 * @return
 *   The element.
 *
 * @see render()
 * @see show()
 */
function hide(&$element) {
  $element['#printed'] = TRUE;
  return $element;
}

/**
 * Shows a hidden element for later rendering.
 *
 * You can also use render($element), which shows the element while rendering
 * it.
 *
 * The first time render() or drupal_render() is called on an element tree,
 * as each element in the tree is rendered, it is marked with a #printed flag
 * and the rendered children of the element are cached. Subsequent calls to
 * render() or drupal_render() will not traverse the child tree of this element
 * again: they will just use the cached children. So if you want to show an
 * element, be sure to call show() on the element before its parent tree is
 * rendered for the first time, as it will have no effect on subsequent
 * renderings of the parent tree.
 *
 * @param $element
 *   The element to be shown.
 *
 * @return
 *   The element.
 *
 * @see render()
 * @see hide()
 */
function show(&$element) {
  $element['#printed'] = FALSE;
  return $element;
}

/**
 * Gets the rendered output of a renderable element from the cache.
 *
 * @param $elements
 *   A renderable array.
 *
 * @return
 *   A markup string containing the rendered content of the element, or FALSE
 *   if no cached copy of the element is available.
 *
 * @see drupal_render()
 * @see drupal_render_cache_set()
 */
function drupal_render_cache_get($elements) {
  if (!in_array($_SERVER['REQUEST_METHOD'], array('GET', 'HEAD')) || !$cid = drupal_render_cid_create($elements)) {
    return FALSE;
  }
  $bin = isset($elements['#cache']['bin']) ? $elements['#cache']['bin'] : 'cache';

  if (!empty($cid) && $cache = cache_get($cid, $bin)) {
    // Add additional libraries, JavaScript, CSS and other data attached
    // to this element.
    if (isset($cache->data['#attached'])) {
      drupal_process_attached($cache->data);
    }
    // Return the rendered output.
    return $cache->data['#markup'];
  }
  return FALSE;
}

/**
 * Caches the rendered output of a renderable element.
 *
 * This is called by drupal_render() if the #cache property is set on an
 * element.
 *
 * @param $markup
 *   The rendered output string of $elements.
 * @param $elements
 *   A renderable array.
 *
 * @see drupal_render_cache_get()
 */
function drupal_render_cache_set(&$markup, $elements) {
  // Create the cache ID for the element.
  if (!in_array($_SERVER['REQUEST_METHOD'], array('GET', 'HEAD')) || !$cid = drupal_render_cid_create($elements)) {
    return FALSE;
  }

  // Cache implementations are allowed to modify the markup, to support
  // replacing markup with edge-side include commands. The supporting cache
  // backend will store the markup in some other key (like
  // $data['#real-value']) and return an include command instead. When the
  // ESI command is executed by the content accelerator, the real value can
  // be retrieved and used.
  $data['#markup'] = &$markup;
  // Persist attached data associated with this element.
  $attached = drupal_render_collect_attached($elements, TRUE);
  if ($attached) {
    $data['#attached'] = $attached;
  }
  $bin = isset($elements['#cache']['bin']) ? $elements['#cache']['bin'] : 'cache';
  $expire = isset($elements['#cache']['expire']) ? $elements['#cache']['expire'] : CACHE_PERMANENT;
  cache_set($cid, $data, $bin, $expire);
}

/**
 * Collects #attached for an element and its children into a single array.
 *
 * When caching elements, it is necessary to collect all libraries, JavaScript
 * and CSS into a single array, from both the element itself and all child
 * elements. This allows drupal_render() to add these back to the page when the
 * element is returned from cache.
 *
 * @param $elements
 *   The element to collect #attached from.
 * @param $return
 *   Whether to return the attached elements and reset the internal static.
 *
 * @return
 *   The #attached array for this element and its descendants.
 */
function drupal_render_collect_attached($elements, $return = FALSE) {
  $attached = &drupal_static(__FUNCTION__, array());

  // Collect all #attached for this element.
  if (isset($elements['#attached'])) {
    foreach ($elements['#attached'] as $key => $value) {
      if (!isset($attached[$key])) {
        $attached[$key] = array();
      }
      $attached[$key] = array_merge($attached[$key], $value);
    }
  }
  if ($children = element_children($elements)) {
    foreach ($children as $child) {
      drupal_render_collect_attached($elements[$child]);
    }
  }

  // If this was the first call to the function, return all attached elements
  // and reset the static cache.
  if ($return) {
    $return = $attached;
    $attached = array();
    return $return;
  }
}

/**
 * Prepares an element for caching based on a query.
 *
 * This smart caching strategy saves Drupal from querying and rendering to HTML
 * when the underlying query is unchanged.
 *
 * Expensive queries should use the query builder to create the query and then
 * call this function. Executing the query and formatting results should happen
 * in a #pre_render callback.
 *
 * @param $query
 *   A select query object as returned by db_select().
 * @param $function
 *   The name of the function doing this caching. A _pre_render suffix will be
 *   added to this string and is also part of the cache key in
 *   drupal_render_cache_set() and drupal_render_cache_get().
 * @param $expire
 *   The cache expire time, passed eventually to cache_set().
 * @param $granularity
 *   One or more granularity constants passed to drupal_render_cid_parts().
 *
 * @return
 *   A renderable array with the following keys and values:
 *   - #query: The passed-in $query.
 *   - #pre_render: $function with a _pre_render suffix.
 *   - #cache: An associative array prepared for drupal_render_cache_set().
 */
function drupal_render_cache_by_query($query, $function, $expire = CACHE_TEMPORARY, $granularity = NULL) {
  $cache_keys = array_merge(array($function), drupal_render_cid_parts($granularity));
  $query->preExecute();
  $cache_keys[] = hash('sha256', serialize(array((string) $query, $query->getArguments())));
  return array(
    '#query' => $query,
    '#pre_render' => array($function . '_pre_render'),
    '#cache' => array(
      'keys' => $cache_keys,
      'expire' => $expire,
    ),
  );
}

/**
 * Returns cache ID parts for building a cache ID.
 *
 * @param $granularity
 *   One or more cache granularity constants. For example, to cache separately
 *   for each user, use DRUPAL_CACHE_PER_USER. To cache separately for each
 *   page and role, use the expression:
 *   @code
 *   DRUPAL_CACHE_PER_PAGE | DRUPAL_CACHE_PER_ROLE
 *   @endcode
 *
 * @return
 *   An array of cache ID parts, always containing the active theme. If the
 *   locale module is enabled it also contains the active language. If
 *   $granularity was passed in, more parts are added.
 */
function drupal_render_cid_parts($granularity = NULL) {
  global $theme, $base_root, $user;

  $cid_parts[] = $theme;
  // If Locale is enabled but we have only one language we do not need it as cid
  // part.
  if (drupal_multilingual()) {
    foreach (language_types_configurable() as $language_type) {
      $cid_parts[] = $GLOBALS[$language_type]->language;
    }
  }

  if (!empty($granularity)) {
    // 'PER_ROLE' and 'PER_USER' are mutually exclusive. 'PER_USER' can be a
    // resource drag for sites with many users, so when a module is being
    // equivocal, we favor the less expensive 'PER_ROLE' pattern.
    if ($granularity & DRUPAL_CACHE_PER_ROLE) {
      $cid_parts[] = 'r.' . implode(',', array_keys($user->roles));
    }
    elseif ($granularity & DRUPAL_CACHE_PER_USER) {
      $cid_parts[] = "u.$user->uid";
    }

    if ($granularity & DRUPAL_CACHE_PER_PAGE) {
      $cid_parts[] = $base_root . request_uri();
    }
  }

  return $cid_parts;
}

/**
 * Creates the cache ID for a renderable element.
 *
 * This creates the cache ID string, either by returning the #cache['cid']
 * property if present or by building the cache ID out of the #cache['keys']
 * and, optionally, the #cache['granularity'] properties.
 *
 * @param $elements
 *   A renderable array.
 *
 * @return
 *   The cache ID string, or FALSE if the element may not be cached.
 */
function drupal_render_cid_create($elements) {
  if (isset($elements['#cache']['cid'])) {
    return $elements['#cache']['cid'];
  }
  elseif (isset($elements['#cache']['keys'])) {
    $granularity = isset($elements['#cache']['granularity']) ? $elements['#cache']['granularity'] : NULL;
    // Merge in additional cache ID parts based provided by drupal_render_cid_parts().
    $cid_parts = array_merge($elements['#cache']['keys'], drupal_render_cid_parts($granularity));
    return implode(':', $cid_parts);
  }
  return FALSE;
}

/**
 * Function used by uasort to sort structured arrays by weight.
 */
function element_sort($a, $b) {
  $a_weight = (is_array($a) && isset($a['#weight'])) ? $a['#weight'] : 0;
  $b_weight = (is_array($b) && isset($b['#weight'])) ? $b['#weight'] : 0;
  if ($a_weight == $b_weight) {
    return 0;
  }
  return ($a_weight < $b_weight) ? -1 : 1;
}

/**
 * Array sorting callback; sorts elements by title.
 */
function element_sort_by_title($a, $b) {
  $a_title = (is_array($a) && isset($a['#title'])) ? $a['#title'] : '';
  $b_title = (is_array($b) && isset($b['#title'])) ? $b['#title'] : '';
  return strnatcasecmp($a_title, $b_title);
}

/**
 * Retrieves the default properties for the defined element type.
 *
 * @param $type
 *   An element type as defined by hook_element_info().
 */
function element_info($type) {
  // Use the advanced drupal_static() pattern, since this is called very often.
  static $drupal_static_fast;
  if (!isset($drupal_static_fast)) {
    $drupal_static_fast['cache'] = &drupal_static(__FUNCTION__);
  }
  $cache = &$drupal_static_fast['cache'];

  if (!isset($cache)) {
    $cache = module_invoke_all('element_info');
    foreach ($cache as $element_type => $info) {
      $cache[$element_type]['#type'] = $element_type;
    }
    // Allow modules to alter the element type defaults.
    drupal_alter('element_info', $cache);
  }

  return isset($cache[$type]) ? $cache[$type] : array();
}

/**
 * Retrieves a single property for the defined element type.
 *
 * @param $type
 *   An element type as defined by hook_element_info().
 * @param $property_name
 *   The property within the element type that should be returned.
 * @param $default
 *   (Optional) The value to return if the element type does not specify a
 *   value for the property. Defaults to NULL.
 */
function element_info_property($type, $property_name, $default = NULL) {
  return (($info = element_info($type)) && array_key_exists($property_name, $info)) ? $info[$property_name] : $default;
}

/**
 * Sorts a structured array by the 'weight' element.
 *
 * Note that the sorting is by the 'weight' array element, not by the render
 * element property '#weight'.
 *
 * Callback for uasort() used in various functions.
 *
 * @param $a
 *   First item for comparison. The compared items should be associative arrays
 *   that optionally include a 'weight' element. For items without a 'weight'
 *   element, a default value of 0 will be used.
 * @param $b
 *   Second item for comparison.
 */
function drupal_sort_weight($a, $b) {
  $a_weight = (is_array($a) && isset($a['weight'])) ? $a['weight'] : 0;
  $b_weight = (is_array($b) && isset($b['weight'])) ? $b['weight'] : 0;
  if ($a_weight == $b_weight) {
    return 0;
  }
  return ($a_weight < $b_weight) ? -1 : 1;
}

/**
 * Array sorting callback; sorts elements by 'title' key.
 */
function drupal_sort_title($a, $b) {
  if (!isset($b['title'])) {
    return -1;
  }
  if (!isset($a['title'])) {
    return 1;
  }
  return strcasecmp($a['title'], $b['title']);
}

/**
 * Checks if the key is a property.
 */
function element_property($key) {
  return $key[0] == '#';
}

/**
 * Gets properties of a structured array element (keys beginning with '#').
 */
function element_properties($element) {
  return array_filter(array_keys((array) $element), 'element_property');
}

/**
 * Checks if the key is a child.
 */
function element_child($key) {
  return !isset($key[0]) || $key[0] != '#';
}

/**
 * Identifies the children of an element array, optionally sorted by weight.
 *
 * The children of a element array are those key/value pairs whose key does
 * not start with a '#'. See drupal_render() for details.
 *
 * @param $elements
 *   The element array whose children are to be identified.
 * @param $sort
 *   Boolean to indicate whether the children should be sorted by weight.
 *
 * @return
 *   The array keys of the element's children.
 */
function element_children(&$elements, $sort = FALSE) {
  // Do not attempt to sort elements which have already been sorted.
  $sort = isset($elements['#sorted']) ? !$elements['#sorted'] : $sort;

  // Filter out properties from the element, leaving only children.
  $children = array();
  $sortable = FALSE;
  foreach ($elements as $key => $value) {
    if ($key === '' || $key[0] !== '#') {
      $children[$key] = $value;
      if (is_array($value) && isset($value['#weight'])) {
        $sortable = TRUE;
      }
    }
  }
  // Sort the children if necessary.
  if ($sort && $sortable) {
    uasort($children, 'element_sort');
    // Put the sorted children back into $elements in the correct order, to
    // preserve sorting if the same element is passed through
    // element_children() twice.
    foreach ($children as $key => $child) {
      unset($elements[$key]);
      $elements[$key] = $child;
    }
    $elements['#sorted'] = TRUE;
  }

  return array_keys($children);
}

/**
 * Returns the visible children of an element.
 *
 * @param $elements
 *   The parent element.
 *
 * @return
 *   The array keys of the element's visible children.
 */
function element_get_visible_children(array $elements) {
  $visible_children = array();

  foreach (element_children($elements) as $key) {
    $child = $elements[$key];

    // Skip un-accessible children.
    if (isset($child['#access']) && !$child['#access']) {
      continue;
    }

    // Skip value and hidden elements, since they are not rendered.
    if (isset($child['#type']) && in_array($child['#type'], array('value', 'hidden'))) {
      continue;
    }

    $visible_children[$key] = $child;
  }

  return array_keys($visible_children);
}

/**
 * Sets HTML attributes based on element properties.
 *
 * @param $element
 *   The renderable element to process.
 * @param $map
 *   An associative array whose keys are element property names and whose values
 *   are the HTML attribute names to set for corresponding the property; e.g.,
 *   array('#propertyname' => 'attributename'). If both names are identical
 *   except for the leading '#', then an attribute name value is sufficient and
 *   no property name needs to be specified.
 */
function element_set_attributes(array &$element, array $map) {
  foreach ($map as $property => $attribute) {
    // If the key is numeric, the attribute name needs to be taken over.
    if (is_int($property)) {
      $property = '#' . $attribute;
    }
    // Do not overwrite already existing attributes.
    if (isset($element[$property]) && !isset($element['#attributes'][$attribute])) {
      $element['#attributes'][$attribute] = $element[$property];
    }
  }
}

/**
 * Recursively computes the difference of arrays with additional index check.
 *
 * This is a version of array_diff_assoc() that supports multidimensional
 * arrays.
 *
 * @param array $array1
 *   The array to compare from.
 * @param array $array2
 *   The array to compare to.
 *
 * @return array
 *   Returns an array containing all the values from array1 that are not present
 *   in array2.
 */
function drupal_array_diff_assoc_recursive($array1, $array2) {
  $difference = array();

  foreach ($array1 as $key => $value) {
    if (is_array($value)) {
      if (!array_key_exists($key, $array2) || !is_array($array2[$key])) {
        $difference[$key] = $value;
      }
      else {
        $new_diff = drupal_array_diff_assoc_recursive($value, $array2[$key]);
        if (!empty($new_diff)) {
          $difference[$key] = $new_diff;
        }
      }
    }
    elseif (!array_key_exists($key, $array2) || $array2[$key] !== $value) {
      $difference[$key] = $value;
    }
  }

  return $difference;
}

/**
 * Sets a value in a nested array with variable depth.
 *
 * This helper function should be used when the depth of the array element you
 * are changing may vary (that is, the number of parent keys is variable). It
 * is primarily used for form structures and renderable arrays.
 *
 * Example:
 * @code
 * // Assume you have a 'signature' element somewhere in a form. It might be:
 * $form['signature_settings']['signature'] = array(
 *   '#type' => 'text_format',
 *   '#title' => t('Signature'),
 * );
 * // Or, it might be further nested:
 * $form['signature_settings']['user']['signature'] = array(
 *   '#type' => 'text_format',
 *   '#title' => t('Signature'),
 * );
 * @endcode
 *
 * To deal with the situation, the code needs to figure out the route to the
 * element, given an array of parents that is either
 * @code array('signature_settings', 'signature') @endcode in the first case or
 * @code array('signature_settings', 'user', 'signature') @endcode in the second
 * case.
 *
 * Without this helper function the only way to set the signature element in one
 * line would be using eval(), which should be avoided:
 * @code
 * // Do not do this! Avoid eval().
 * eval('$form[\'' . implode("']['", $parents) . '\'] = $element;');
 * @endcode
 *
 * Instead, use this helper function:
 * @code
 * drupal_array_set_nested_value($form, $parents, $element);
 * @endcode
 *
 * However if the number of array parent keys is static, the value should always
 * be set directly rather than calling this function. For instance, for the
 * first example we could just do:
 * @code
 * $form['signature_settings']['signature'] = $element;
 * @endcode
 *
 * @param $array
 *   A reference to the array to modify.
 * @param $parents
 *   An array of parent keys, starting with the outermost key.
 * @param $value
 *   The value to set.
 * @param $force
 *   (Optional) If TRUE, the value is forced into the structure even if it
 *   requires the deletion of an already existing non-array parent value. If
 *   FALSE, PHP throws an error if trying to add into a value that is not an
 *   array. Defaults to FALSE.
 *
 * @see drupal_array_get_nested_value()
 */
function drupal_array_set_nested_value(array &$array, array $parents, $value, $force = FALSE) {
  $ref = &$array;
  foreach ($parents as $parent) {
    // PHP auto-creates container arrays and NULL entries without error if $ref
    // is NULL, but throws an error if $ref is set, but not an array.
    if ($force && isset($ref) && !is_array($ref)) {
      $ref = array();
    }
    $ref = &$ref[$parent];
  }
  $ref = $value;
}

/**
 * Retrieves a value from a nested array with variable depth.
 *
 * This helper function should be used when the depth of the array element being
 * retrieved may vary (that is, the number of parent keys is variable). It is
 * primarily used for form structures and renderable arrays.
 *
 * Without this helper function the only way to get a nested array value with
 * variable depth in one line would be using eval(), which should be avoided:
 * @code
 * // Do not do this! Avoid eval().
 * // May also throw a PHP notice, if the variable array keys do not exist.
 * eval('$value = $array[\'' . implode("']['", $parents) . "'];");
 * @endcode
 *
 * Instead, use this helper function:
 * @code
 * $value = drupal_array_get_nested_value($form, $parents);
 * @endcode
 *
 * A return value of NULL is ambiguous, and can mean either that the requested
 * key does not exist, or that the actual value is NULL. If it is required to
 * know whether the nested array key actually exists, pass a third argument that
 * is altered by reference:
 * @code
 * $key_exists = NULL;
 * $value = drupal_array_get_nested_value($form, $parents, $key_exists);
 * if ($key_exists) {
 *   // ... do something with $value ...
 * }
 * @endcode
 *
 * However if the number of array parent keys is static, the value should always
 * be retrieved directly rather than calling this function. For instance:
 * @code
 * $value = $form['signature_settings']['signature'];
 * @endcode
 *
 * @param $array
 *   The array from which to get the value.
 * @param $parents
 *   An array of parent keys of the value, starting with the outermost key.
 * @param $key_exists
 *   (optional) If given, an already defined variable that is altered by
 *   reference.
 *
 * @return
 *   The requested nested value. Possibly NULL if the value is NULL or not all
 *   nested parent keys exist. $key_exists is altered by reference and is a
 *   Boolean that indicates whether all nested parent keys exist (TRUE) or not
 *   (FALSE). This allows to distinguish between the two possibilities when NULL
 *   is returned.
 *
 * @see drupal_array_set_nested_value()
 */
function &drupal_array_get_nested_value(array &$array, array $parents, &$key_exists = NULL) {
  $ref = &$array;
  foreach ($parents as $parent) {
    if (is_array($ref) && array_key_exists($parent, $ref)) {
      $ref = &$ref[$parent];
    }
    else {
      $key_exists = FALSE;
      $null = NULL;
      return $null;
    }
  }
  $key_exists = TRUE;
  return $ref;
}

/**
 * Determines whether a nested array contains the requested keys.
 *
 * This helper function should be used when the depth of the array element to be
 * checked may vary (that is, the number of parent keys is variable). See
 * drupal_array_set_nested_value() for details. It is primarily used for form
 * structures and renderable arrays.
 *
 * If it is required to also get the value of the checked nested key, use
 * drupal_array_get_nested_value() instead.
 *
 * If the number of array parent keys is static, this helper function is
 * unnecessary and the following code can be used instead:
 * @code
 * $value_exists = isset($form['signature_settings']['signature']);
 * $key_exists = array_key_exists('signature', $form['signature_settings']);
 * @endcode
 *
 * @param $array
 *   The array with the value to check for.
 * @param $parents
 *   An array of parent keys of the value, starting with the outermost key.
 *
 * @return
 *   TRUE if all the parent keys exist, FALSE otherwise.
 *
 * @see drupal_array_get_nested_value()
 */
function drupal_array_nested_key_exists(array $array, array $parents) {
  // Although this function is similar to PHP's array_key_exists(), its
  // arguments should be consistent with drupal_array_get_nested_value().
  $key_exists = NULL;
  drupal_array_get_nested_value($array, $parents, $key_exists);
  return $key_exists;
}

/**
 * Provides theme registration for themes across .inc files.
 */
function drupal_common_theme() {
  return array(
    // From theme.inc.
    'html' => array(
      'render element' => 'page',
      'template' => 'html',
    ),
    'page' => array(
      'render element' => 'page',
      'template' => 'page',
    ),
    'region' => array(
      'render element' => 'elements',
      'template' => 'region',
    ),
    'status_messages' => array(
      'variables' => array('display' => NULL),
    ),
    'link' => array(
      'variables' => array('text' => NULL, 'path' => NULL, 'options' => array()),
    ),
    'links' => array(
      'variables' => array('links' => NULL, 'attributes' => array('class' => array('links')), 'heading' => array()),
    ),
    'image' => array(
      // HTML 4 and XHTML 1.0 always require an alt attribute. The HTML 5 draft
      // allows the alt attribute to be omitted in some cases. Therefore,
      // default the alt attribute to an empty string, but allow code calling
      // theme('image') to pass explicit NULL for it to be omitted. Usually,
      // neither omission nor an empty string satisfies accessibility
      // requirements, so it is strongly encouraged for code calling
      // theme('image') to pass a meaningful value for the alt variable.
      // - http://www.w3.org/TR/REC-html40/struct/objects.html#h-13.8
      // - http://www.w3.org/TR/xhtml1/dtds.html
      // - http://dev.w3.org/html5/spec/Overview.html#alt
      // The title attribute is optional in all cases, so it is omitted by
      // default.
      'variables' => array('path' => NULL, 'width' => NULL, 'height' => NULL, 'alt' => '', 'title' => NULL, 'attributes' => array()),
    ),
    'breadcrumb' => array(
      'variables' => array('breadcrumb' => NULL),
    ),
    'help' => array(
      'variables' => array(),
    ),
    'table' => array(
      'variables' => array('header' => NULL, 'rows' => NULL, 'attributes' => array(), 'caption' => NULL, 'colgroups' => array(), 'sticky' => TRUE, 'empty' => ''),
    ),
    'tablesort_indicator' => array(
      'variables' => array('style' => NULL),
    ),
    'mark' => array(
      'variables' => array('type' => MARK_NEW),
    ),
    'item_list' => array(
      'variables' => array('items' => array(), 'title' => NULL, 'type' => 'ul', 'attributes' => array()),
    ),
    'more_help_link' => array(
      'variables' => array('url' => NULL),
    ),
    'feed_icon' => array(
      'variables' => array('url' => NULL, 'title' => NULL),
    ),
    'more_link' => array(
      'variables' => array('url' => NULL, 'title' => NULL)
    ),
    'username' => array(
      'variables' => array('account' => NULL),
    ),
    'progress_bar' => array(
      'variables' => array('percent' => NULL, 'message' => NULL),
    ),
    'indentation' => array(
      'variables' => array('size' => 1),
    ),
    'html_tag' => array(
      'render element' => 'element',
    ),
    // From theme.maintenance.inc.
    'maintenance_page' => array(
      'variables' => array('content' => NULL, 'show_messages' => TRUE),
      'template' => 'maintenance-page',
    ),
    'update_page' => array(
      'variables' => array('content' => NULL, 'show_messages' => TRUE),
    ),
    'install_page' => array(
      'variables' => array('content' => NULL),
    ),
    'task_list' => array(
      'variables' => array('items' => NULL, 'active' => NULL),
    ),
    'authorize_message' => array(
      'variables' => array('message' => NULL, 'success' => TRUE),
    ),
    'authorize_report' => array(
      'variables' => array('messages' => array()),
    ),
    // From pager.inc.
    'pager' => array(
      'variables' => array('tags' => array(), 'element' => 0, 'parameters' => array(), 'quantity' => 9),
    ),
    'pager_first' => array(
      'variables' => array('text' => NULL, 'element' => 0, 'parameters' => array()),
    ),
    'pager_previous' => array(
      'variables' => array('text' => NULL, 'element' => 0, 'interval' => 1, 'parameters' => array()),
    ),
    'pager_next' => array(
      'variables' => array('text' => NULL, 'element' => 0, 'interval' => 1, 'parameters' => array()),
    ),
    'pager_last' => array(
      'variables' => array('text' => NULL, 'element' => 0, 'parameters' => array()),
    ),
    'pager_link' => array(
      'variables' => array('text' => NULL, 'page_new' => NULL, 'element' => NULL, 'parameters' => array(), 'attributes' => array()),
    ),
    // From menu.inc.
    'menu_link' => array(
      'render element' => 'element',
    ),
    'menu_tree' => array(
      'render element' => 'tree',
    ),
    'menu_local_task' => array(
      'render element' => 'element',
    ),
    'menu_local_action' => array(
      'render element' => 'element',
    ),
    'menu_local_tasks' => array(
      'variables' => array('primary' => array(), 'secondary' => array()),
    ),
    // From form.inc.
    'select' => array(
      'render element' => 'element',
    ),
    'fieldset' => array(
      'render element' => 'element',
    ),
    'radio' => array(
      'render element' => 'element',
    ),
    'radios' => array(
      'render element' => 'element',
    ),
    'date' => array(
      'render element' => 'element',
    ),
    'exposed_filters' => array(
      'render element' => 'form',
    ),
    'checkbox' => array(
      'render element' => 'element',
    ),
    'checkboxes' => array(
      'render element' => 'element',
    ),
    'button' => array(
      'render element' => 'element',
    ),
    'image_button' => array(
      'render element' => 'element',
    ),
    'hidden' => array(
      'render element' => 'element',
    ),
    'textfield' => array(
      'render element' => 'element',
    ),
    'form' => array(
      'render element' => 'element',
    ),
    'textarea' => array(
      'render element' => 'element',
    ),
    'password' => array(
      'render element' => 'element',
    ),
    'file' => array(
      'render element' => 'element',
    ),
    'tableselect' => array(
      'render element' => 'element',
    ),
    'form_element' => array(
      'render element' => 'element',
    ),
    'form_required_marker' => array(
      'render element' => 'element',
    ),
    'form_element_label' => array(
      'render element' => 'element',
    ),
    'vertical_tabs' => array(
      'render element' => 'element',
    ),
    'container' => array(
      'render element' => 'element',
    ),
  );
}

/**
 * @addtogroup schemaapi
 * @{
 */

/**
 * Creates all tables defined in a module's hook_schema().
 *
 * Note: This function does not pass the module's schema through
 * hook_schema_alter(). The module's tables will be created exactly as the
 * module defines them.
 *
 * @param $module
 *   The module for which the tables will be created.
 */
function drupal_install_schema($module) {
  $schema = drupal_get_schema_unprocessed($module);
  _drupal_schema_initialize($schema, $module, FALSE);

  foreach ($schema as $name => $table) {
    db_create_table($name, $table);
  }
}

/**
 * Removes all tables defined in a module's hook_schema().
 *
 * Note: This function does not pass the module's schema through
 * hook_schema_alter(). The module's tables will be created exactly as the
 * module defines them.
 *
 * @param $module
 *   The module for which the tables will be removed.
 *
 * @return
 *   An array of arrays with the following key/value pairs:
 *    - success: a boolean indicating whether the query succeeded.
 *    - query: the SQL query(s) executed, passed through check_plain().
 */
function drupal_uninstall_schema($module) {
  $schema = drupal_get_schema_unprocessed($module);
  _drupal_schema_initialize($schema, $module, FALSE);

  foreach ($schema as $table) {
    if (db_table_exists($table['name'])) {
      db_drop_table($table['name']);
    }
  }
}

/**
 * Returns the unprocessed and unaltered version of a module's schema.
 *
 * Use this function only if you explicitly need the original
 * specification of a schema, as it was defined in a module's
 * hook_schema(). No additional default values will be set,
 * hook_schema_alter() is not invoked and these unprocessed
 * definitions won't be cached.
 *
 * This function can be used to retrieve a schema specification in
 * hook_schema(), so it allows you to derive your tables from existing
 * specifications.
 *
 * It is also used by drupal_install_schema() and
 * drupal_uninstall_schema() to ensure that a module's tables are
 * created exactly as specified without any changes introduced by a
 * module that implements hook_schema_alter().
 *
 * @param $module
 *   The module to which the table belongs.
 * @param $table
 *   The name of the table. If not given, the module's complete schema
 *   is returned.
 */
function drupal_get_schema_unprocessed($module, $table = NULL) {
  // Load the .install file to get hook_schema.
  module_load_install($module);
  $schema = module_invoke($module, 'schema');

  if (isset($table) && isset($schema[$table])) {
    return $schema[$table];
  }
  elseif (!empty($schema)) {
    return $schema;
  }
  return array();
}

/**
 * Fills in required default values for table definitions from hook_schema().
 *
 * @param $schema
 *   The schema definition array as it was returned by the module's
 *   hook_schema().
 * @param $module
 *   The module for which hook_schema() was invoked.
 * @param $remove_descriptions
 *   (optional) Whether to additionally remove 'description' keys of all tables
 *   and fields to improve performance of serialize() and unserialize().
 *   Defaults to TRUE.
 */
function _drupal_schema_initialize(&$schema, $module, $remove_descriptions = TRUE) {
  // Set the name and module key for all tables.
  foreach ($schema as $name => &$table) {
    if (empty($table['module'])) {
      $table['module'] = $module;
    }
    if (!isset($table['name'])) {
      $table['name'] = $name;
    }
    if ($remove_descriptions) {
      unset($table['description']);
      foreach ($table['fields'] as &$field) {
        unset($field['description']);
      }
    }
  }
}

/**
 * Retrieves the type for every field in a table schema.
 *
 * @param $table
 *   The name of the table from which to retrieve type information.
 *
 * @return
 *   An array of types, keyed by field name.
 */
function drupal_schema_field_types($table) {
  $table_schema = drupal_get_schema($table);
  foreach ($table_schema['fields'] as $field_name => $field_info) {
    $field_types[$field_name] = isset($field_info['type']) ? $field_info['type'] : NULL;
  }
  return $field_types;
}

/**
 * Retrieves a list of fields from a table schema.
 *
 * The returned list is suitable for use in an SQL query.
 *
 * @param $table
 *   The name of the table from which to retrieve fields.
 * @param
 *   An optional prefix to to all fields.
 *
 * @return An array of fields.
 */
function drupal_schema_fields_sql($table, $prefix = NULL) {
  $schema = drupal_get_schema($table);
  $fields = array_keys($schema['fields']);
  if ($prefix) {
    $columns = array();
    foreach ($fields as $field) {
      $columns[] = "$prefix.$field";
    }
    return $columns;
  }
  else {
    return $fields;
  }
}

/**
 * Saves (inserts or updates) a record to the database based upon the schema.
 *
 * Do not use drupal_write_record() within hook_update_N() functions, since the
 * database schema cannot be relied upon when a user is running a series of
 * updates. Instead, use db_insert() or db_update() to save the record.
 *
 * @param $table
 *   The name of the table; this must be defined by a hook_schema()
 *   implementation.
 * @param $record
 *   An object or array representing the record to write, passed in by
 *   reference. If inserting a new record, values not provided in $record will
 *   be populated in $record and in the database with the default values from
 *   the schema, as well as a single serial (auto-increment) field (if present).
 *   If updating an existing record, only provided values are updated in the
 *   database, and $record is not modified.
 * @param $primary_keys
 *   To indicate that this is a new record to be inserted, omit this argument.
 *   If this is an update, this argument specifies the primary keys' field
 *   names. If there is only 1 field in the key, you may pass in a string; if
 *   there are multiple fields in the key, pass in an array.
 *
 * @return
 *   If the record insert or update failed, returns FALSE. If it succeeded,
 *   returns SAVED_NEW or SAVED_UPDATED, depending on the operation performed.
 */
function drupal_write_record($table, &$record, $primary_keys = array()) {
  // Standardize $primary_keys to an array.
  if (is_string($primary_keys)) {
    $primary_keys = array($primary_keys);
  }

  $schema = drupal_get_schema($table);
  if (empty($schema)) {
    return FALSE;
  }

  $object = (object) $record;
  $fields = array();

  // Go through the schema to determine fields to write.
  foreach ($schema['fields'] as $field => $info) {
    if ($info['type'] == 'serial') {
      // Skip serial types if we are updating.
      if (!empty($primary_keys)) {
        continue;
      }
      // Track serial field so we can helpfully populate them after the query.
      // NOTE: Each table should come with one serial field only.
      $serial = $field;
    }

    // Skip field if it is in $primary_keys as it is unnecessary to update a
    // field to the value it is already set to.
    if (in_array($field, $primary_keys)) {
      continue;
    }

    if (!property_exists($object, $field)) {
      // Skip fields that are not provided, default values are already known
      // by the database.
      continue;
    }

    // Build array of fields to update or insert.
    if (empty($info['serialize'])) {
      $fields[$field] = $object->$field;
    }
    else {
      $fields[$field] = serialize($object->$field);
    }

    // Type cast to proper datatype, except when the value is NULL and the
    // column allows this.
    //
    // MySQL PDO silently casts e.g. FALSE and '' to 0 when inserting the value
    // into an integer column, but PostgreSQL PDO does not. Also type cast NULL
    // when the column does not allow this.
    if (isset($object->$field) || !empty($info['not null'])) {
      if ($info['type'] == 'int' || $info['type'] == 'serial') {
        $fields[$field] = (int) $fields[$field];
      }
      elseif ($info['type'] == 'float') {
        $fields[$field] = (float) $fields[$field];
      }
      else {
        $fields[$field] = (string) $fields[$field];
      }
    }
  }

  if (empty($fields)) {
    return;
  }

  // Build the SQL.
  if (empty($primary_keys)) {
    // We are doing an insert.
    $options = array('return' => Database::RETURN_INSERT_ID);
    if (isset($serial) && isset($fields[$serial])) {
      // If the serial column has been explicitly set with an ID, then we don't
      // require the database to return the last insert id.
      if ($fields[$serial]) {
        $options['return'] = Database::RETURN_AFFECTED;
      }
      // If a serial column does exist with no value (i.e. 0) then remove it as
      // the database will insert the correct value for us.
      else {
        unset($fields[$serial]);
      }
    }
    $query = db_insert($table, $options)->fields($fields);
    $return = SAVED_NEW;
  }
  else {
    $query = db_update($table)->fields($fields);
    foreach ($primary_keys as $key) {
      $query->condition($key, $object->$key);
    }
    $return = SAVED_UPDATED;
  }

  // Execute the SQL.
  if ($query_return = $query->execute()) {
    if (isset($serial)) {
      // If the database was not told to return the last insert id, it will be
      // because we already know it.
      if (isset($options) && $options['return'] != Database::RETURN_INSERT_ID) {
        $object->$serial = $fields[$serial];
      }
      else {
        $object->$serial = $query_return;
      }
    }
  }
  // If we have a single-field primary key but got no insert ID, the
  // query failed. Note that we explicitly check for FALSE, because
  // a valid update query which doesn't change any values will return
  // zero (0) affected rows.
  elseif ($query_return === FALSE && count($primary_keys) == 1) {
    $return = FALSE;
  }

  // If we are inserting, populate empty fields with default values.
  if (empty($primary_keys)) {
    foreach ($schema['fields'] as $field => $info) {
      if (isset($info['default']) && !property_exists($object, $field)) {
        $object->$field = $info['default'];
      }
    }
  }

  // If we began with an array, convert back.
  if (is_array($record)) {
    $record = (array) $object;
  }

  return $return;
}

/**
 * @} End of "addtogroup schemaapi".
 */

/**
 * Parses Drupal module and theme .info files.
 *
 * Info files are NOT for placing arbitrary theme and module-specific settings.
 * Use variable_get() and variable_set() for that.
 *
 * Information stored in a module .info file:
 * - name: The real name of the module for display purposes.
 * - description: A brief description of the module.
 * - dependencies: An array of shortnames of other modules this module requires.
 * - package: The name of the package of modules this module belongs to.
 *
 * See forum.info for an example of a module .info file.
 *
 * Information stored in a theme .info file:
 * - name: The real name of the theme for display purposes.
 * - description: Brief description.
 * - screenshot: Path to screenshot relative to the theme's .info file.
 * - engine: Theme engine; typically phptemplate.
 * - base: Name of a base theme, if applicable; e.g., base = zen.
 * - regions: Listed regions; e.g., region[left] = Left sidebar.
 * - features: Features available; e.g., features[] = logo.
 * - stylesheets: Theme stylesheets; e.g., stylesheets[all][] = my-style.css.
 * - scripts: Theme scripts; e.g., scripts[] = my-script.js.
 *
 * See bartik.info for an example of a theme .info file.
 *
 * @param $filename
 *   The file we are parsing. Accepts file with relative or absolute path.
 *
 * @return
 *   The info array.
 *
 * @see drupal_parse_info_format()
 */
function drupal_parse_info_file($filename) {
  $info = &drupal_static(__FUNCTION__, array());

  if (!isset($info[$filename])) {
    if (!file_exists($filename)) {
      $info[$filename] = array();
    }
    else {
      $data = file_get_contents($filename);
      $info[$filename] = drupal_parse_info_format($data);
    }
  }
  return $info[$filename];
}

/**
 * Parses data in Drupal's .info format.
 *
 * Data should be in an .ini-like format to specify values. White-space
 * generally doesn't matter, except inside values:
 * @code
 *   key = value
 *   key = "value"
 *   key = 'value'
 *   key = "multi-line
 *   value"
 *   key = 'multi-line
 *   value'
 *   key
 *   =
 *   'value'
 * @endcode
 *
 * Arrays are created using a HTTP GET alike syntax:
 * @code
 *   key[] = "numeric array"
 *   key[index] = "associative array"
 *   key[index][] = "nested numeric array"
 *   key[index][index] = "nested associative array"
 * @endcode
 *
 * PHP constants are substituted in, but only when used as the entire value.
 * Comments should start with a semi-colon at the beginning of a line.
 *
 * @param $data
 *   A string to parse.
 *
 * @return
 *   The info array.
 *
 * @see drupal_parse_info_file()
 */
function drupal_parse_info_format($data) {
  $info = array();
  $constants = get_defined_constants();

  if (preg_match_all('
    @^\s*                           # Start at the beginning of a line, ignoring leading whitespace
    ((?:
      [^=;\[\]]|                    # Key names cannot contain equal signs, semi-colons or square brackets,
      \[[^\[\]]*\]                  # unless they are balanced and not nested
    )+?)
    \s*=\s*                         # Key/value pairs are separated by equal signs (ignoring white-space)
    (?:
      ("(?:[^"]|(?<=\\\\)")*")|     # Double-quoted string, which may contain slash-escaped quotes/slashes
      (\'(?:[^\']|(?<=\\\\)\')*\')| # Single-quoted string, which may contain slash-escaped quotes/slashes
      ([^\r\n]*?)                   # Non-quoted string
    )\s*$                           # Stop at the next end of a line, ignoring trailing whitespace
    @msx', $data, $matches, PREG_SET_ORDER)) {
    foreach ($matches as $match) {
      // Fetch the key and value string.
      $i = 0;
      foreach (array('key', 'value1', 'value2', 'value3') as $var) {
        $$var = isset($match[++$i]) ? $match[$i] : '';
      }
      $value = stripslashes(substr($value1, 1, -1)) . stripslashes(substr($value2, 1, -1)) . $value3;

      // Parse array syntax.
      $keys = preg_split('/\]?\[/', rtrim($key, ']'));
      $last = array_pop($keys);
      $parent = &$info;

      // Create nested arrays.
      foreach ($keys as $key) {
        if ($key == '') {
          $key = count($parent);
        }
        if (!isset($parent[$key]) || !is_array($parent[$key])) {
          $parent[$key] = array();
        }
        $parent = &$parent[$key];
      }

      // Handle PHP constants.
      if (isset($constants[$value])) {
        $value = $constants[$value];
      }

      // Insert actual value.
      if ($last == '') {
        $last = count($parent);
      }
      $parent[$last] = $value;
    }
  }

  return $info;
}

/**
 * Returns a list of severity levels, as defined in RFC 3164.
 *
 * @return
 *   Array of the possible severity levels for log messages.
 *
 * @see http://www.ietf.org/rfc/rfc3164.txt
 * @see watchdog()
 * @ingroup logging_severity_levels
 */
function watchdog_severity_levels() {
  return array(
    WATCHDOG_EMERGENCY => t('emergency'),
    WATCHDOG_ALERT     => t('alert'),
    WATCHDOG_CRITICAL  => t('critical'),
    WATCHDOG_ERROR     => t('error'),
    WATCHDOG_WARNING   => t('warning'),
    WATCHDOG_NOTICE    => t('notice'),
    WATCHDOG_INFO      => t('info'),
    WATCHDOG_DEBUG     => t('debug'),
  );
}


/**
 * Explodes a string of tags into an array.
 *
 * @see drupal_implode_tags()
 */
function drupal_explode_tags($tags) {
  // This regexp allows the following types of user input:
  // this, "somecompany, llc", "and ""this"" w,o.rks", foo bar
  $regexp = '%(?:^|,\ *)("(?>[^"]*)(?>""[^"]* )*"|(?: [^",]*))%x';
  preg_match_all($regexp, $tags, $matches);
  $typed_tags = array_unique($matches[1]);

  $tags = array();
  foreach ($typed_tags as $tag) {
    // If a user has escaped a term (to demonstrate that it is a group,
    // or includes a comma or quote character), we remove the escape
    // formatting so to save the term into the database as the user intends.
    $tag = trim(str_replace('""', '"', preg_replace('/^"(.*)"$/', '\1', $tag)));
    if ($tag != "") {
      $tags[] = $tag;
    }
  }

  return $tags;
}

/**
 * Implodes an array of tags into a string.
 *
 * @see drupal_explode_tags()
 */
function drupal_implode_tags($tags) {
  $encoded_tags = array();
  foreach ($tags as $tag) {
    // Commas and quotes in tag names are special cases, so encode them.
    if (strpos($tag, ',') !== FALSE || strpos($tag, '"') !== FALSE) {
      $tag = '"' . str_replace('"', '""', $tag) . '"';
    }

    $encoded_tags[] = $tag;
  }
  return implode(', ', $encoded_tags);
}

/**
 * Flushes all cached data on the site.
 *
 * Empties cache tables, rebuilds the menu cache and theme registries, and
 * invokes a hook so that other modules' cache data can be cleared as well.
 */
function drupal_flush_all_caches() {
  // Change query-strings on css/js files to enforce reload for all users.
  _drupal_flush_css_js();

  registry_rebuild();
  drupal_clear_css_cache();
  drupal_clear_js_cache();

  // Rebuild the theme data. Note that the module data is rebuilt above, as
  // part of registry_rebuild().
  system_rebuild_theme_data();
  drupal_theme_rebuild();

  entity_info_cache_clear();
  node_types_rebuild();
  // node_menu() defines menu items based on node types so it needs to come
  // after node types are rebuilt.
  menu_rebuild();

  // Synchronize to catch any actions that were added or removed.
  actions_synchronize();

  // Don't clear cache_form - in-progress form submissions may break.
  // Ordered so clearing the page cache will always be the last action.
  $core = array('cache', 'cache_path', 'cache_filter', 'cache_bootstrap', 'cache_page');
  $cache_tables = array_merge(module_invoke_all('flush_caches'), $core);
  foreach ($cache_tables as $table) {
    cache_clear_all('*', $table, TRUE);
  }

  // Rebuild the bootstrap module list. We do this here so that developers
  // can get new hook_boot() implementations registered without having to
  // write a hook_update_N() function.
  _system_update_bootstrap_status();
}

/**
 * Changes the dummy query string added to all CSS and JavaScript files.
 *
 * Changing the dummy query string appended to CSS and JavaScript files forces
 * all browsers to reload fresh files.
 */
function _drupal_flush_css_js() {
  // The timestamp is converted to base 36 in order to make it more compact.
  variable_set('css_js_query_string', base_convert(REQUEST_TIME, 10, 36));
}

/**
 * Outputs debug information.
 *
 * The debug information is passed on to trigger_error() after being converted
 * to a string using _drupal_debug_message().
 *
 * @param $data
 *   Data to be output.
 * @param $label
 *   Label to prefix the data.
 * @param $print_r
 *   Flag to switch between print_r() and var_export() for data conversion to
 *   string. Set $print_r to TRUE when dealing with a recursive data structure
 *   as var_export() will generate an error.
 */
function debug($data, $label = NULL, $print_r = FALSE) {
  // Print $data contents to string.
  $string = check_plain($print_r ? print_r($data, TRUE) : var_export($data, TRUE));

  // Display values with pre-formatting to increase readability.
  $string = '<pre>' . $string . '</pre>';

  trigger_error(trim($label ? "$label: $string" : $string));
}

/**
 * Parses a dependency for comparison by drupal_check_incompatibility().
 *
 * @param $dependency
 *   A dependency string, for example 'foo (>=7.x-4.5-beta5, 3.x)'.
 *
 * @return
 *   An associative array with three keys:
 *   - 'name' includes the name of the thing to depend on (e.g. 'foo').
 *   - 'original_version' contains the original version string (which can be
 *     used in the UI for reporting incompatibilities).
 *   - 'versions' is a list of associative arrays, each containing the keys
 *     'op' and 'version'. 'op' can be one of: '=', '==', '!=', '<>', '<',
 *     '<=', '>', or '>='. 'version' is one piece like '4.5-beta3'.
 *   Callers should pass this structure to drupal_check_incompatibility().
 *
 * @see drupal_check_incompatibility()
 */
function drupal_parse_dependency($dependency) {
  // We use named subpatterns and support every op that version_compare
  // supports. Also, op is optional and defaults to equals.
  $p_op = '(?P<operation>!=|==|=|<|<=|>|>=|<>)?';
  // Core version is always optional: 7.x-2.x and 2.x is treated the same.
  $p_core = '(?:' . preg_quote(DRUPAL_CORE_COMPATIBILITY) . '-)?';
  $p_major = '(?P<major>\d+)';
  // By setting the minor version to x, branches can be matched.
  $p_minor = '(?P<minor>(?:\d+|x)(?:-[A-Za-z]+\d+)?)';
  $value = array();
  $parts = explode('(', $dependency, 2);
  $value['name'] = trim($parts[0]);
  if (isset($parts[1])) {
    $value['original_version'] = ' (' . $parts[1];
    foreach (explode(',', $parts[1]) as $version) {
      if (preg_match("/^\s*$p_op\s*$p_core$p_major\.$p_minor/", $version, $matches)) {
        $op = !empty($matches['operation']) ? $matches['operation'] : '=';
        if ($matches['minor'] == 'x') {
          // Drupal considers "2.x" to mean any version that begins with
          // "2" (e.g. 2.0, 2.9 are all "2.x"). PHP's version_compare(),
          // on the other hand, treats "x" as a string; so to
          // version_compare(), "2.x" is considered less than 2.0. This
          // means that >=2.x and <2.x are handled by version_compare()
          // as we need, but > and <= are not.
          if ($op == '>' || $op == '<=') {
            $matches['major']++;
          }
          // Equivalence can be checked by adding two restrictions.
          if ($op == '=' || $op == '==') {
            $value['versions'][] = array('op' => '<', 'version' => ($matches['major'] + 1) . '.x');
            $op = '>=';
          }
        }
        $value['versions'][] = array('op' => $op, 'version' => $matches['major'] . '.' . $matches['minor']);
      }
    }
  }
  return $value;
}

/**
 * Checks whether a version is compatible with a given dependency.
 *
 * @param $v
 *   The parsed dependency structure from drupal_parse_dependency().
 * @param $current_version
 *   The version to check against (like 4.2).
 *
 * @return
 *   NULL if compatible, otherwise the original dependency version string that
 *   caused the incompatibility.
 *
 * @see drupal_parse_dependency()
 */
function drupal_check_incompatibility($v, $current_version) {
  if (!empty($v['versions'])) {
    foreach ($v['versions'] as $required_version) {
      if ((isset($required_version['op']) && !version_compare($current_version, $required_version['version'], $required_version['op']))) {
        return $v['original_version'];
      }
    }
  }
}

/**
 * Get the entity info array of an entity type.
 *
 * @param $entity_type
 *   The entity type, e.g. node, for which the info shall be returned, or NULL
 *   to return an array with info about all types.
 *
 * @see hook_entity_info()
 * @see hook_entity_info_alter()
 */
function entity_get_info($entity_type = NULL) {
  global $language;

  // Use the advanced drupal_static() pattern, since this is called very often.
  static $drupal_static_fast;
  if (!isset($drupal_static_fast)) {
    $drupal_static_fast['entity_info'] = &drupal_static(__FUNCTION__);
  }
  $entity_info = &$drupal_static_fast['entity_info'];

  // hook_entity_info() includes translated strings, so each language is cached
  // separately.
  $langcode = $language->language;

  if (empty($entity_info)) {
    if ($cache = cache_get("entity_info:$langcode")) {
      $entity_info = $cache->data;
    }
    else {
      $entity_info = module_invoke_all('entity_info');
      // Merge in default values.
      foreach ($entity_info as $name => $data) {
        $entity_info[$name] += array(
          'fieldable' => FALSE,
          'controller class' => 'DrupalDefaultEntityController',
          'static cache' => TRUE,
          'field cache' => TRUE,
          'load hook' => $name . '_load',
          'bundles' => array(),
          'view modes' => array(),
          'entity keys' => array(),
          'translation' => array(),
        );
        $entity_info[$name]['entity keys'] += array(
          'revision' => '',
          'bundle' => '',
        );
        foreach ($entity_info[$name]['view modes'] as $view_mode => $view_mode_info) {
          $entity_info[$name]['view modes'][$view_mode] += array(
            'custom settings' => FALSE,
          );
        }
        // If no bundle key is provided, assume a single bundle, named after
        // the entity type.
        if (empty($entity_info[$name]['entity keys']['bundle']) && empty($entity_info[$name]['bundles'])) {
          $entity_info[$name]['bundles'] = array($name => array('label' => $entity_info[$name]['label']));
        }
        // Prepare entity schema fields SQL info for
        // DrupalEntityControllerInterface::buildQuery().
        if (isset($entity_info[$name]['base table'])) {
          $entity_info[$name]['base table field types'] = drupal_schema_field_types($entity_info[$name]['base table']);
          $entity_info[$name]['schema_fields_sql']['base table'] = drupal_schema_fields_sql($entity_info[$name]['base table']);
          if (isset($entity_info[$name]['revision table'])) {
            $entity_info[$name]['schema_fields_sql']['revision table'] = drupal_schema_fields_sql($entity_info[$name]['revision table']);
          }
        }
      }
      // Let other modules alter the entity info.
      drupal_alter('entity_info', $entity_info);
      cache_set("entity_info:$langcode", $entity_info);
    }
  }

  if (empty($entity_type)) {
    return $entity_info;
  }
  elseif (isset($entity_info[$entity_type])) {
    return $entity_info[$entity_type];
  }
}

/**
 * Resets the cached information about entity types.
 */
function entity_info_cache_clear() {
  drupal_static_reset('entity_get_info');
  // Clear all languages.
  cache_clear_all('entity_info:', 'cache', TRUE);
}

/**
 * Helper function to extract id, vid, and bundle name from an entity.
 *
 * @param $entity_type
 *   The entity type; e.g. 'node' or 'user'.
 * @param $entity
 *   The entity from which to extract values.
 *
 * @return
 *   A numerically indexed array (not a hash table) containing these
 *   elements:
 *   - 0: Primary ID of the entity.
 *   - 1: Revision ID of the entity, or NULL if $entity_type is not versioned.
 *   - 2: Bundle name of the entity, or NULL if $entity_type has no bundles.
 */
function entity_extract_ids($entity_type, $entity) {
  $info = entity_get_info($entity_type);

  // Objects being created might not have id/vid yet.
  $id = isset($entity->{$info['entity keys']['id']}) ? $entity->{$info['entity keys']['id']} : NULL;
  $vid = ($info['entity keys']['revision'] && isset($entity->{$info['entity keys']['revision']})) ? $entity->{$info['entity keys']['revision']} : NULL;

  if (!empty($info['entity keys']['bundle'])) {
    // Explicitly fail for malformed entities missing the bundle property.
    if (!isset($entity->{$info['entity keys']['bundle']}) || $entity->{$info['entity keys']['bundle']} === '') {
      throw new EntityMalformedException(t('Missing bundle property on entity of type @entity_type.', array('@entity_type' => $entity_type)));
    }
    $bundle = $entity->{$info['entity keys']['bundle']};
  }
  else {
    // The entity type provides no bundle key: assume a single bundle, named
    // after the entity type.
    $bundle = $entity_type;
  }

  return array($id, $vid, $bundle);
}

/**
 * Helper function to assemble an object structure with initial ids.
 *
 * This function can be seen as reciprocal to entity_extract_ids().
 *
 * @param $entity_type
 *   The entity type; e.g. 'node' or 'user'.
 * @param $ids
 *   A numerically indexed array, as returned by entity_extract_ids().
 *
 * @return
 *   An entity structure, initialized with the ids provided.
 *
 * @see entity_extract_ids()
 */
function entity_create_stub_entity($entity_type, $ids) {
  $entity = new stdClass();
  $info = entity_get_info($entity_type);
  $entity->{$info['entity keys']['id']} = $ids[0];
  if (!empty($info['entity keys']['revision']) && isset($ids[1])) {
    $entity->{$info['entity keys']['revision']} = $ids[1];
  }
  if (!empty($info['entity keys']['bundle']) && isset($ids[2])) {
    $entity->{$info['entity keys']['bundle']} = $ids[2];
  }
  return $entity;
}

/**
 * Load entities from the database.
 *
 * The entities are stored in a static memory cache, and will not require
 * database access if loaded again during the same page request.
 *
 * The actual loading is done through a class that has to implement the
 * DrupalEntityControllerInterface interface. By default,
 * DrupalDefaultEntityController is used. Entity types can specify that a
 * different class should be used by setting the 'controller class' key in
 * hook_entity_info(). These classes can either implement the
 * DrupalEntityControllerInterface interface, or, most commonly, extend the
 * DrupalDefaultEntityController class. See node_entity_info() and the
 * NodeController in node.module as an example.
 *
 * @param $entity_type
 *   The entity type to load, e.g. node or user.
 * @param $ids
 *   An array of entity IDs, or FALSE to load all entities.
 * @param $conditions
 *   (deprecated) An associative array of conditions on the base table, where
 *   the keys are the database fields and the values are the values those
 *   fields must have. Instead, it is preferable to use EntityFieldQuery to
 *   retrieve a list of entity IDs loadable by this function.
 * @param $reset
 *   Whether to reset the internal cache for the requested entity type.
 *
 * @return
 *   An array of entity objects indexed by their ids. When no results are
 *   found, an empty array is returned.
 *
 * @todo Remove $conditions in Drupal 8.
 *
 * @see hook_entity_info()
 * @see DrupalEntityControllerInterface
 * @see DrupalDefaultEntityController
 * @see EntityFieldQuery
 */
function entity_load($entity_type, $ids = FALSE, $conditions = array(), $reset = FALSE) {
  if ($reset) {
    entity_get_controller($entity_type)->resetCache();
  }
  return entity_get_controller($entity_type)->load($ids, $conditions);
}

/**
 * Loads the unchanged, i.e. not modified, entity from the database.
 *
 * Unlike entity_load() this function ensures the entity is directly loaded from
 * the database, thus bypassing any static cache. In particular, this function
 * is useful to determine changes by comparing the entity being saved to the
 * stored entity.
 *
 * @param $entity_type
 *   The entity type to load, e.g. node or user.
 * @param $id
 *   The ID of the entity to load.
 *
 * @return
 *   The unchanged entity, or FALSE if the entity cannot be loaded.
 */
function entity_load_unchanged($entity_type, $id) {
  entity_get_controller($entity_type)->resetCache(array($id));
  $result = entity_get_controller($entity_type)->load(array($id));
  return reset($result);
}

/**
 * Gets the entity controller for an entity type.
 *
 * @return DrupalEntityControllerInterface
 *   The entity controller object for the specified entity type.
 */
function entity_get_controller($entity_type) {
  $controllers = &drupal_static(__FUNCTION__, array());
  if (!isset($controllers[$entity_type])) {
    $type_info = entity_get_info($entity_type);
    $class = $type_info['controller class'];
    $controllers[$entity_type] = new $class($entity_type);
  }
  return $controllers[$entity_type];
}

/**
 * Invoke hook_entity_prepare_view().
 *
 * If adding a new entity similar to nodes, comments or users, you should
 * invoke this function during the ENTITY_build_content() or
 * ENTITY_view_multiple() phases of rendering to allow other modules to alter
 * the objects during this phase. This is needed for situations where
 * information needs to be loaded outside of ENTITY_load() - particularly
 * when loading entities into one another - i.e. a user object into a node, due
 * to the potential for unwanted side-effects such as caching and infinite
 * recursion. By convention, entity_prepare_view() is called after
 * field_attach_prepare_view() to allow entity level hooks to act on content
 * loaded by field API.
 *
 * @param $entity_type
 *   The type of entity, i.e. 'node', 'user'.
 * @param $entities
 *   The entity objects which are being prepared for view, keyed by object ID.
 * @param $langcode
 *   (optional) A language code to be used for rendering. Defaults to the global
 *   content language of the current request.
 *
 * @see hook_entity_prepare_view()
 */
function entity_prepare_view($entity_type, $entities, $langcode = NULL) {
  if (!isset($langcode)) {
    $langcode = $GLOBALS['language_content']->language;
  }

  // To ensure hooks are only run once per entity, check for an
  // entity_view_prepared flag and only process items without it.
  // @todo: resolve this more generally for both entity and field level hooks.
  $prepare = array();
  foreach ($entities as $id => $entity) {
    if (empty($entity->entity_view_prepared)) {
      // Add this entity to the items to be prepared.
      $prepare[$id] = $entity;

      // Mark this item as prepared.
      $entity->entity_view_prepared = TRUE;
    }
  }

  if (!empty($prepare)) {
    module_invoke_all('entity_prepare_view', $prepare, $entity_type, $langcode);
  }
}

/**
 * Invoke hook_entity_view_mode_alter().
 *
 * If adding a new entity similar to nodes, comments or users, you should invoke
 * this function during the ENTITY_build_content() or ENTITY_view_multiple()
 * phases of rendering to allow other modules to alter the view mode during this
 * phase. This function needs to be called before field_attach_prepare_view() to
 * ensure that the correct content is loaded by field API.
 *
 * @param $entity_type
 *   The type of entity, i.e. 'node', 'user'.
 * @param $entities
 *   The entity objects which are being prepared for view, keyed by object ID.
 * @param $view_mode
 *   The original view mode e.g. 'full', 'teaser'...
 * @param $langcode
 *   (optional) A language code to be used for rendering. Defaults to the global
 *   content language of the current request.
 * @return
 *   An associative array with arrays of entities keyed by view mode.
 *
 * @see hook_entity_view_mode_alter()
 */
function entity_view_mode_prepare($entity_type, $entities, $view_mode, $langcode = NULL) {
  if (!isset($langcode)) {
    $langcode = $GLOBALS['language_content']->language;
  }

  // To ensure hooks are never run after field_attach_prepare_view() only
  // process items without the entity_view_prepared flag.
  $entities_by_view_mode = array();
  foreach ($entities as $id => $entity) {
    $entity_view_mode = $view_mode;
    if (empty($entity->entity_view_prepared)) {

      // Allow modules to change the view mode.
      $context = array(
        'entity_type' => $entity_type,
        'entity' => $entity,
        'langcode' => $langcode,
      );
      drupal_alter('entity_view_mode', $entity_view_mode, $context);
    }

    $entities_by_view_mode[$entity_view_mode][$id] = $entity;
  }

  return $entities_by_view_mode;
}

/**
 * Returns the URI elements of an entity.
 *
 * @param $entity_type
 *   The entity type; e.g. 'node' or 'user'.
 * @param $entity
 *   The entity for which to generate a path.
 * @return
 *   An array containing the 'path' and 'options' keys used to build the URI of
 *   the entity, and matching the signature of url(). NULL if the entity has no
 *   URI of its own.
 */
function entity_uri($entity_type, $entity) {
  $info = entity_get_info($entity_type);
  list($id, $vid, $bundle) = entity_extract_ids($entity_type, $entity);

  // A bundle-specific callback takes precedence over the generic one for the
  // entity type.
  if (isset($info['bundles'][$bundle]['uri callback'])) {
    $uri_callback = $info['bundles'][$bundle]['uri callback'];
  }
  elseif (isset($info['uri callback'])) {
    $uri_callback = $info['uri callback'];
  }
  else {
    return NULL;
  }

  // Invoke the callback to get the URI. If there is no callback, return NULL.
  if (isset($uri_callback) && function_exists($uri_callback)) {
    $uri = $uri_callback($entity);
    // Pass the entity data to url() so that alter functions do not need to
    // lookup this entity again.
    $uri['options']['entity_type'] = $entity_type;
    $uri['options']['entity'] = $entity;
    return $uri;
  }
}

/**
 * Returns the label of an entity.
 *
 * See the 'label callback' component of the hook_entity_info() return value
 * for more information.
 *
 * @param $entity_type
 *   The entity type; e.g., 'node' or 'user'.
 * @param $entity
 *   The entity for which to generate the label.
 *
 * @return
 *   The entity label, or FALSE if not found.
 */
function entity_label($entity_type, $entity) {
  $label = FALSE;
  $info = entity_get_info($entity_type);
  if (isset($info['label callback']) && function_exists($info['label callback'])) {
    $label = $info['label callback']($entity, $entity_type);
  }
  elseif (!empty($info['entity keys']['label']) && isset($entity->{$info['entity keys']['label']})) {
    $label = $entity->{$info['entity keys']['label']};
  }

  return $label;
}

/**
 * Returns the language of an entity.
 *
 * @param $entity_type
 *   The entity type; e.g., 'node' or 'user'.
 * @param $entity
 *   The entity for which to get the language.
 *
 * @return
 *   A valid language code or NULL if the entity has no language support.
 */
function entity_language($entity_type, $entity) {
  $info = entity_get_info($entity_type);

  // Invoke the callback to get the language. If there is no callback, try to
  // get it from a property of the entity, otherwise NULL.
  if (isset($info['language callback']) && function_exists($info['language callback'])) {
    $langcode = $info['language callback']($entity_type, $entity);
  }
  elseif (!empty($info['entity keys']['language']) && isset($entity->{$info['entity keys']['language']})) {
    $langcode = $entity->{$info['entity keys']['language']};
  }
  else {
    // The value returned in D8 would be LANGUAGE_NONE, we cannot use it here to
    // preserve backward compatibility. In fact this function has been
    // introduced very late in the D7 life cycle, mainly as the proper default
    // for field_attach_form(). By returning LANGUAGE_NONE when no language
    // information is available, we would introduce a potentially BC-breaking
    // API change, since field_attach_form() defaults to the default language
    // instead of LANGUAGE_NONE. Moreover this allows us to distinguish between
    // entities that have no language specified from ones that do not have
    // language support at all.
    $langcode = NULL;
  }

  return $langcode;
}

/**
 * Attaches field API validation to entity forms.
 */
function entity_form_field_validate($entity_type, $form, &$form_state) {
  // All field attach API functions act on an entity object, but during form
  // validation, we don't have one. $form_state contains the entity as it was
  // prior to processing the current form submission, and we must not update it
  // until we have fully validated the submitted input. Therefore, for
  // validation, act on a pseudo entity created out of the form values.
  $pseudo_entity = (object) $form_state['values'];
  field_attach_form_validate($entity_type, $pseudo_entity, $form, $form_state);
}

/**
 * Copies submitted values to entity properties for simple entity forms.
 *
 * During the submission handling of an entity form's "Save", "Preview", and
 * possibly other buttons, the form state's entity needs to be updated with the
 * submitted form values. Each entity form implements its own builder function
 * for doing this, appropriate for the particular entity and form, whereas
 * modules may specify additional builder functions in $form['#entity_builders']
 * for copying the form values of added form elements to entity properties.
 * Many of the main entity builder functions can call this helper function to
 * re-use its logic of copying $form_state['values'][PROPERTY] values to
 * $entity->PROPERTY for all entries in $form_state['values'] that are not field
 * data, and calling field_attach_submit() to copy field data. Apart from that
 * this helper invokes any additional builder functions that have been specified
 * in $form['#entity_builders'].
 *
 * For some entity forms (e.g., forms with complex non-field data and forms that
 * simultaneously edit multiple entities), this behavior may be inappropriate,
 * so the builder function for such forms needs to implement the required
 * functionality instead of calling this function.
 */
function entity_form_submit_build_entity($entity_type, $entity, $form, &$form_state) {
  $info = entity_get_info($entity_type);
  list(, , $bundle) = entity_extract_ids($entity_type, $entity);

  // Copy top-level form values that are not for fields to entity properties,
  // without changing existing entity properties that are not being edited by
  // this form. Copying field values must be done using field_attach_submit().
  $values_excluding_fields = $info['fieldable'] ? array_diff_key($form_state['values'], field_info_instances($entity_type, $bundle)) : $form_state['values'];
  foreach ($values_excluding_fields as $key => $value) {
    $entity->$key = $value;
  }

  // Invoke all specified builders for copying form values to entity properties.
  if (isset($form['#entity_builders'])) {
    foreach ($form['#entity_builders'] as $function) {
      $function($entity_type, $entity, $form, $form_state);
    }
  }

  // Copy field values to the entity.
  if ($info['fieldable']) {
    field_attach_submit($entity_type, $entity, $form, $form_state);
  }
}

/**
 * Performs one or more XML-RPC request(s).
 *
 * Usage example:
 * @code
 * $result = xmlrpc('http://example.com/xmlrpc.php', array(
 *   'service.methodName' => array($parameter, $second, $third),
 * ));
 * @endcode
 *
 * @param $url
 *   An absolute URL of the XML-RPC endpoint.
 * @param $args
 *   An associative array whose keys are the methods to call and whose values
 *   are the arguments to pass to the respective method. If multiple methods
 *   are specified, a system.multicall is performed.
 * @param $options
 *   (optional) An array of options to pass along to drupal_http_request().
 *
 * @return
 *   For one request:
 *     Either the return value of the method on success, or FALSE.
 *     If FALSE is returned, see xmlrpc_errno() and xmlrpc_error_msg().
 *   For multiple requests:
 *     An array of results. Each result will either be the result
 *     returned by the method called, or an xmlrpc_error object if the call
 *     failed. See xmlrpc_error().
 */
function xmlrpc($url, $args, $options = array()) {
  require_once DRUPAL_ROOT . '/includes/xmlrpc.inc';
  return _xmlrpc($url, $args, $options);
}

/**
 * Retrieves a list of all available archivers.
 *
 * @see hook_archiver_info()
 * @see hook_archiver_info_alter()
 */
function archiver_get_info() {
  $archiver_info = &drupal_static(__FUNCTION__, array());

  if (empty($archiver_info)) {
    $cache = cache_get('archiver_info');
    if ($cache === FALSE) {
      // Rebuild the cache and save it.
      $archiver_info = module_invoke_all('archiver_info');
      drupal_alter('archiver_info', $archiver_info);
      uasort($archiver_info, 'drupal_sort_weight');
      cache_set('archiver_info', $archiver_info);
    }
    else {
      $archiver_info = $cache->data;
    }
  }

  return $archiver_info;
}

/**
 * Returns a string of supported archive extensions.
 *
 * @return
 *   A space-separated string of extensions suitable for use by the file
 *   validation system.
 */
function archiver_get_extensions() {
  $valid_extensions = array();
  foreach (archiver_get_info() as $archive) {
    foreach ($archive['extensions'] as $extension) {
      foreach (explode('.', $extension) as $part) {
        if (!in_array($part, $valid_extensions)) {
          $valid_extensions[] = $part;
        }
      }
    }
  }
  return implode(' ', $valid_extensions);
}

/**
 * Creates the appropriate archiver for the specified file.
 *
 * @param $file
 *   The full path of the archive file. Note that stream wrapper paths are
 *   supported, but not remote ones.
 *
 * @return
 *   A newly created instance of the archiver class appropriate
 *   for the specified file, already bound to that file.
 *   If no appropriate archiver class was found, will return FALSE.
 */
function archiver_get_archiver($file) {
  // Archivers can only work on local paths
  $filepath = drupal_realpath($file);
  if (!is_file($filepath)) {
    throw new Exception(t('Archivers can only operate on local files: %file not supported', array('%file' => $file)));
  }
  $archiver_info = archiver_get_info();

  foreach ($archiver_info as $implementation) {
    foreach ($implementation['extensions'] as $extension) {
      // Because extensions may be multi-part, such as .tar.gz,
      // we cannot use simpler approaches like substr() or pathinfo().
      // This method isn't quite as clean but gets the job done.
      // Also note that the file may not yet exist, so we cannot rely
      // on fileinfo() or other disk-level utilities.
      if (strrpos($filepath, '.' . $extension) === strlen($filepath) - strlen('.' . $extension)) {
        return new $implementation['class']($filepath);
      }
    }
  }
}

/**
 * Assembles the Drupal Updater registry.
 *
 * An Updater is a class that knows how to update various parts of the Drupal
 * file system, for example to update modules that have newer releases, or to
 * install a new theme.
 *
 * @return
 *   The Drupal Updater class registry.
 *
 * @see hook_updater_info()
 * @see hook_updater_info_alter()
 */
function drupal_get_updaters() {
  $updaters = &drupal_static(__FUNCTION__);
  if (!isset($updaters)) {
    $updaters = module_invoke_all('updater_info');
    drupal_alter('updater_info', $updaters);
    uasort($updaters, 'drupal_sort_weight');
  }
  return $updaters;
}

/**
 * Assembles the Drupal FileTransfer registry.
 *
 * @return
 *   The Drupal FileTransfer class registry.
 *
 * @see FileTransfer
 * @see hook_filetransfer_info()
 * @see hook_filetransfer_info_alter()
 */
function drupal_get_filetransfer_info() {
  $info = &drupal_static(__FUNCTION__);
  if (!isset($info)) {
    // Since we have to manually set the 'file path' default for each
    // module separately, we can't use module_invoke_all().
    $info = array();
    foreach (module_implements('filetransfer_info') as $module) {
      $function = $module . '_filetransfer_info';
      if (function_exists($function)) {
        $result = $function();
        if (isset($result) && is_array($result)) {
          foreach ($result as &$values) {
            if (empty($values['file path'])) {
              $values['file path'] = drupal_get_path('module', $module);
            }
          }
          $info = array_merge_recursive($info, $result);
        }
      }
    }
    drupal_alter('filetransfer_info', $info);
    uasort($info, 'drupal_sort_weight');
  }
  return $info;
}