pluggable.php 105 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
<?php
/**
 * These functions can be replaced via plugins. If plugins do not redefine these
 * functions, then these will be used instead.
 *
 * @package WordPress
 */

if ( ! function_exists( 'wp_set_current_user' ) ) :
	/**
	 * Changes the current user by ID or name.
	 *
	 * Set $id to null and specify a name if you do not know a user's ID.
	 *
	 * Some WordPress functionality is based on the current user and not based on
	 * the signed in user. Therefore, it opens the ability to edit and perform
	 * actions on users who aren't signed in.
	 *
	 * @since 2.0.3
	 *
	 * @global WP_User $current_user The current user object which holds the user data.
	 *
	 * @param int|null $id   User ID.
	 * @param string   $name User's username.
	 * @return WP_User Current user User object.
	 */
	function wp_set_current_user( $id, $name = '' ) {
		global $current_user;

		// If `$id` matches the current user, there is nothing to do.
		if ( isset( $current_user )
		&& ( $current_user instanceof WP_User )
		&& ( $id == $current_user->ID )
		&& ( null !== $id )
		) {
			return $current_user;
		}

		$current_user = new WP_User( $id, $name );

		setup_userdata( $current_user->ID );

		/**
		 * Fires after the current user is set.
		 *
		 * @since 2.0.1
		 */
		do_action( 'set_current_user' );

		return $current_user;
	}
endif;

if ( ! function_exists( 'wp_get_current_user' ) ) :
	/**
	 * Retrieve the current user object.
	 *
	 * Will set the current user, if the current user is not set. The current user
	 * will be set to the logged-in person. If no user is logged-in, then it will
	 * set the current user to 0, which is invalid and won't have any permissions.
	 *
	 * @since 2.0.3
	 *
	 * @see _wp_get_current_user()
	 * @global WP_User $current_user Checks if the current user is set.
	 *
	 * @return WP_User Current WP_User instance.
	 */
	function wp_get_current_user() {
		return _wp_get_current_user();
	}
endif;

if ( ! function_exists( 'get_userdata' ) ) :
	/**
	 * Retrieve user info by user ID.
	 *
	 * @since 0.71
	 *
	 * @param int $user_id User ID
	 * @return WP_User|false WP_User object on success, false on failure.
	 */
	function get_userdata( $user_id ) {
		return get_user_by( 'id', $user_id );
	}
endif;

if ( ! function_exists( 'get_user_by' ) ) :
	/**
	 * Retrieve user info by a given field
	 *
	 * @since 2.8.0
	 * @since 4.4.0 Added 'ID' as an alias of 'id' for the `$field` parameter.
	 * @since 5.8.0 Returns the global `$current_user` if it's the user being fetched.
	 *
	 * @global WP_User $current_user The current user object which holds the user data.
	 *
	 * @param string     $field The field to retrieve the user with. id | ID | slug | email | login.
	 * @param int|string $value A value for $field. A user ID, slug, email address, or login name.
	 * @return WP_User|false WP_User object on success, false on failure.
	 */
	function get_user_by( $field, $value ) {
		global $current_user;

		$userdata = WP_User::get_data_by( $field, $value );

		if ( ! $userdata ) {
			return false;
		}

		if ( $current_user instanceof WP_User && $current_user->ID === (int) $userdata->ID ) {
			return $current_user;
		}

		$user = new WP_User;
		$user->init( $userdata );

		return $user;
	}
endif;

if ( ! function_exists( 'cache_users' ) ) :
	/**
	 * Retrieve info for user lists to prevent multiple queries by get_userdata()
	 *
	 * @since 3.0.0
	 *
	 * @global wpdb $wpdb WordPress database abstraction object.
	 *
	 * @param int[] $user_ids User ID numbers list
	 */
	function cache_users( $user_ids ) {
		global $wpdb;

		$clean = _get_non_cached_ids( $user_ids, 'users' );

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

		$list = implode( ',', $clean );

		$users = $wpdb->get_results( "SELECT * FROM $wpdb->users WHERE ID IN ($list)" );

		$ids = array();
		foreach ( $users as $user ) {
			update_user_caches( $user );
			$ids[] = $user->ID;
		}
		update_meta_cache( 'user', $ids );
	}
endif;

if ( ! function_exists( 'wp_mail' ) ) :
	/**
	 * Sends an email, similar to PHP's mail function.
	 *
	 * A true return value does not automatically mean that the user received the
	 * email successfully. It just only means that the method used was able to
	 * process the request without any errors.
	 *
	 * The default content type is `text/plain` which does not allow using HTML.
	 * However, you can set the content type of the email by using the
	 * {@see 'wp_mail_content_type'} filter.
	 *
	 * The default charset is based on the charset used on the blog. The charset can
	 * be set using the {@see 'wp_mail_charset'} filter.
	 *
	 * @since 1.2.1
	 * @since 5.5.0 is_email() is used for email validation,
	 *              instead of PHPMailer's default validator.
	 *
	 * @global PHPMailer\PHPMailer\PHPMailer $phpmailer
	 *
	 * @param string|string[] $to          Array or comma-separated list of email addresses to send message.
	 * @param string          $subject     Email subject.
	 * @param string          $message     Message contents.
	 * @param string|string[] $headers     Optional. Additional headers.
	 * @param string|string[] $attachments Optional. Paths to files to attach.
	 * @return bool Whether the email was sent successfully.
	 */
	function wp_mail( $to, $subject, $message, $headers = '', $attachments = array() ) {
		// Compact the input, apply the filters, and extract them back out.

		/**
		 * Filters the wp_mail() arguments.
		 *
		 * @since 2.2.0
		 *
		 * @param array $args {
		 *     Array of the `wp_mail()` arguments.
		 *
		 *     @type string|string[] $to          Array or comma-separated list of email addresses to send message.
		 *     @type string          $subject     Email subject.
		 *     @type string          $message     Message contents.
		 *     @type string|string[] $headers     Additional headers.
		 *     @type string|string[] $attachments Paths to files to attach.
		 * }
		 */
		$atts = apply_filters( 'wp_mail', compact( 'to', 'subject', 'message', 'headers', 'attachments' ) );

		/**
		 * Filters whether to preempt sending an email.
		 *
		 * Returning a non-null value will short-circuit {@see wp_mail()}, returning
		 * that value instead. A boolean return value should be used to indicate whether
		 * the email was successfully sent.
		 *
		 * @since 5.7.0
		 *
		 * @param null|bool $return Short-circuit return value.
		 * @param array     $atts {
		 *     Array of the `wp_mail()` arguments.
		 *
		 *     @type string|string[] $to          Array or comma-separated list of email addresses to send message.
		 *     @type string          $subject     Email subject.
		 *     @type string          $message     Message contents.
		 *     @type string|string[] $headers     Additional headers.
		 *     @type string|string[] $attachments Paths to files to attach.
		 * }
		 */
		$pre_wp_mail = apply_filters( 'pre_wp_mail', null, $atts );

		if ( null !== $pre_wp_mail ) {
			return $pre_wp_mail;
		}

		if ( isset( $atts['to'] ) ) {
			$to = $atts['to'];
		}

		if ( ! is_array( $to ) ) {
			$to = explode( ',', $to );
		}

		if ( isset( $atts['subject'] ) ) {
			$subject = $atts['subject'];
		}

		if ( isset( $atts['message'] ) ) {
			$message = $atts['message'];
		}

		if ( isset( $atts['headers'] ) ) {
			$headers = $atts['headers'];
		}

		if ( isset( $atts['attachments'] ) ) {
			$attachments = $atts['attachments'];
		}

		if ( ! is_array( $attachments ) ) {
			$attachments = explode( "\n", str_replace( "\r\n", "\n", $attachments ) );
		}
		global $phpmailer;

		// (Re)create it, if it's gone missing.
		if ( ! ( $phpmailer instanceof PHPMailer\PHPMailer\PHPMailer ) ) {
			require_once ABSPATH . WPINC . '/PHPMailer/PHPMailer.php';
			require_once ABSPATH . WPINC . '/PHPMailer/SMTP.php';
			require_once ABSPATH . WPINC . '/PHPMailer/Exception.php';
			$phpmailer = new PHPMailer\PHPMailer\PHPMailer( true );

			$phpmailer::$validator = static function ( $email ) {
				return (bool) is_email( $email );
			};
		}

		// Headers.
		$cc       = array();
		$bcc      = array();
		$reply_to = array();

		if ( empty( $headers ) ) {
			$headers = array();
		} else {
			if ( ! is_array( $headers ) ) {
				// Explode the headers out, so this function can take
				// both string headers and an array of headers.
				$tempheaders = explode( "\n", str_replace( "\r\n", "\n", $headers ) );
			} else {
				$tempheaders = $headers;
			}
			$headers = array();

			// If it's actually got contents.
			if ( ! empty( $tempheaders ) ) {
				// Iterate through the raw headers.
				foreach ( (array) $tempheaders as $header ) {
					if ( strpos( $header, ':' ) === false ) {
						if ( false !== stripos( $header, 'boundary=' ) ) {
							$parts    = preg_split( '/boundary=/i', trim( $header ) );
							$boundary = trim( str_replace( array( "'", '"' ), '', $parts[1] ) );
						}
						continue;
					}
					// Explode them out.
					list( $name, $content ) = explode( ':', trim( $header ), 2 );

					// Cleanup crew.
					$name    = trim( $name );
					$content = trim( $content );

					switch ( strtolower( $name ) ) {
						// Mainly for legacy -- process a "From:" header if it's there.
						case 'from':
							$bracket_pos = strpos( $content, '<' );
							if ( false !== $bracket_pos ) {
								// Text before the bracketed email is the "From" name.
								if ( $bracket_pos > 0 ) {
									$from_name = substr( $content, 0, $bracket_pos - 1 );
									$from_name = str_replace( '"', '', $from_name );
									$from_name = trim( $from_name );
								}

								$from_email = substr( $content, $bracket_pos + 1 );
								$from_email = str_replace( '>', '', $from_email );
								$from_email = trim( $from_email );

								// Avoid setting an empty $from_email.
							} elseif ( '' !== trim( $content ) ) {
								$from_email = trim( $content );
							}
							break;
						case 'content-type':
							if ( strpos( $content, ';' ) !== false ) {
								list( $type, $charset_content ) = explode( ';', $content );
								$content_type                   = trim( $type );
								if ( false !== stripos( $charset_content, 'charset=' ) ) {
									$charset = trim( str_replace( array( 'charset=', '"' ), '', $charset_content ) );
								} elseif ( false !== stripos( $charset_content, 'boundary=' ) ) {
									$boundary = trim( str_replace( array( 'BOUNDARY=', 'boundary=', '"' ), '', $charset_content ) );
									$charset  = '';
								}

								// Avoid setting an empty $content_type.
							} elseif ( '' !== trim( $content ) ) {
								$content_type = trim( $content );
							}
							break;
						case 'cc':
							$cc = array_merge( (array) $cc, explode( ',', $content ) );
							break;
						case 'bcc':
							$bcc = array_merge( (array) $bcc, explode( ',', $content ) );
							break;
						case 'reply-to':
							$reply_to = array_merge( (array) $reply_to, explode( ',', $content ) );
							break;
						default:
							// Add it to our grand headers array.
							$headers[ trim( $name ) ] = trim( $content );
							break;
					}
				}
			}
		}

		// Empty out the values that may be set.
		$phpmailer->clearAllRecipients();
		$phpmailer->clearAttachments();
		$phpmailer->clearCustomHeaders();
		$phpmailer->clearReplyTos();

		// Set "From" name and email.

		// If we don't have a name from the input headers.
		if ( ! isset( $from_name ) ) {
			$from_name = 'WordPress';
		}

		/*
		 * If we don't have an email from the input headers, default to wordpress@$sitename
		 * Some hosts will block outgoing mail from this address if it doesn't exist,
		 * but there's no easy alternative. Defaulting to admin_email might appear to be
		 * another option, but some hosts may refuse to relay mail from an unknown domain.
		 * See https://core.trac.wordpress.org/ticket/5007.
		 */
		if ( ! isset( $from_email ) ) {
			// Get the site domain and get rid of www.
			$sitename   = wp_parse_url( network_home_url(), PHP_URL_HOST );
			$from_email = 'wordpress@';

			if ( null !== $sitename ) {
				if ( 'www.' === substr( $sitename, 0, 4 ) ) {
					$sitename = substr( $sitename, 4 );
				}

				$from_email .= $sitename;
			}
		}

		/**
		 * Filters the email address to send from.
		 *
		 * @since 2.2.0
		 *
		 * @param string $from_email Email address to send from.
		 */
		$from_email = apply_filters( 'wp_mail_from', $from_email );

		/**
		 * Filters the name to associate with the "from" email address.
		 *
		 * @since 2.3.0
		 *
		 * @param string $from_name Name associated with the "from" email address.
		 */
		$from_name = apply_filters( 'wp_mail_from_name', $from_name );

		try {
			$phpmailer->setFrom( $from_email, $from_name, false );
		} catch ( PHPMailer\PHPMailer\Exception $e ) {
			$mail_error_data                             = compact( 'to', 'subject', 'message', 'headers', 'attachments' );
			$mail_error_data['phpmailer_exception_code'] = $e->getCode();

			/** This filter is documented in wp-includes/pluggable.php */
			do_action( 'wp_mail_failed', new WP_Error( 'wp_mail_failed', $e->getMessage(), $mail_error_data ) );

			return false;
		}

		// Set mail's subject and body.
		$phpmailer->Subject = $subject;
		$phpmailer->Body    = $message;

		// Set destination addresses, using appropriate methods for handling addresses.
		$address_headers = compact( 'to', 'cc', 'bcc', 'reply_to' );

		foreach ( $address_headers as $address_header => $addresses ) {
			if ( empty( $addresses ) ) {
				continue;
			}

			foreach ( (array) $addresses as $address ) {
				try {
					// Break $recipient into name and address parts if in the format "Foo <bar@baz.com>".
					$recipient_name = '';

					if ( preg_match( '/(.*)<(.+)>/', $address, $matches ) ) {
						if ( count( $matches ) == 3 ) {
							$recipient_name = $matches[1];
							$address        = $matches[2];
						}
					}

					switch ( $address_header ) {
						case 'to':
							$phpmailer->addAddress( $address, $recipient_name );
							break;
						case 'cc':
							$phpmailer->addCc( $address, $recipient_name );
							break;
						case 'bcc':
							$phpmailer->addBcc( $address, $recipient_name );
							break;
						case 'reply_to':
							$phpmailer->addReplyTo( $address, $recipient_name );
							break;
					}
				} catch ( PHPMailer\PHPMailer\Exception $e ) {
					continue;
				}
			}
		}

		// Set to use PHP's mail().
		$phpmailer->isMail();

		// Set Content-Type and charset.

		// If we don't have a content-type from the input headers.
		if ( ! isset( $content_type ) ) {
			$content_type = 'text/plain';
		}

		/**
		 * Filters the wp_mail() content type.
		 *
		 * @since 2.3.0
		 *
		 * @param string $content_type Default wp_mail() content type.
		 */
		$content_type = apply_filters( 'wp_mail_content_type', $content_type );

		$phpmailer->ContentType = $content_type;

		// Set whether it's plaintext, depending on $content_type.
		if ( 'text/html' === $content_type ) {
			$phpmailer->isHTML( true );
		}

		// If we don't have a charset from the input headers.
		if ( ! isset( $charset ) ) {
			$charset = get_bloginfo( 'charset' );
		}

		/**
		 * Filters the default wp_mail() charset.
		 *
		 * @since 2.3.0
		 *
		 * @param string $charset Default email charset.
		 */
		$phpmailer->CharSet = apply_filters( 'wp_mail_charset', $charset );

		// Set custom headers.
		if ( ! empty( $headers ) ) {
			foreach ( (array) $headers as $name => $content ) {
				// Only add custom headers not added automatically by PHPMailer.
				if ( ! in_array( $name, array( 'MIME-Version', 'X-Mailer' ), true ) ) {
					try {
						$phpmailer->addCustomHeader( sprintf( '%1$s: %2$s', $name, $content ) );
					} catch ( PHPMailer\PHPMailer\Exception $e ) {
						continue;
					}
				}
			}

			if ( false !== stripos( $content_type, 'multipart' ) && ! empty( $boundary ) ) {
				$phpmailer->addCustomHeader( sprintf( 'Content-Type: %s; boundary="%s"', $content_type, $boundary ) );
			}
		}

		if ( ! empty( $attachments ) ) {
			foreach ( $attachments as $attachment ) {
				try {
					$phpmailer->addAttachment( $attachment );
				} catch ( PHPMailer\PHPMailer\Exception $e ) {
					continue;
				}
			}
		}

		/**
		 * Fires after PHPMailer is initialized.
		 *
		 * @since 2.2.0
		 *
		 * @param PHPMailer $phpmailer The PHPMailer instance (passed by reference).
		 */
		do_action_ref_array( 'phpmailer_init', array( &$phpmailer ) );

		$mail_data = compact( 'to', 'subject', 'message', 'headers', 'attachments' );

		// Send!
		try {
			$send = $phpmailer->send();

			/**
			 * Fires after PHPMailer has successfully sent an email.
			 *
			 * The firing of this action does not necessarily mean that the recipient(s) received the
			 * email successfully. It only means that the `send` method above was able to
			 * process the request without any errors.
			 *
			 * @since 5.9.0
			 *
			 * @param array $mail_data {
			 *     An array containing the email recipient(s), subject, message, headers, and attachments.
			 *
			 *     @type string[] $to          Email addresses to send message.
			 *     @type string   $subject     Email subject.
			 *     @type string   $message     Message contents.
			 *     @type string[] $headers     Additional headers.
			 *     @type string[] $attachments Paths to files to attach.
			 * }
			 */
			do_action( 'wp_mail_succeeded', $mail_data );

			return $send;
		} catch ( PHPMailer\PHPMailer\Exception $e ) {
			$mail_data['phpmailer_exception_code'] = $e->getCode();

			/**
			 * Fires after a PHPMailer\PHPMailer\Exception is caught.
			 *
			 * @since 4.4.0
			 *
			 * @param WP_Error $error A WP_Error object with the PHPMailer\PHPMailer\Exception message, and an array
			 *                        containing the mail recipient, subject, message, headers, and attachments.
			 */
			do_action( 'wp_mail_failed', new WP_Error( 'wp_mail_failed', $e->getMessage(), $mail_data ) );

			return false;
		}
	}
endif;

if ( ! function_exists( 'wp_authenticate' ) ) :
	/**
	 * Authenticate a user, confirming the login credentials are valid.
	 *
	 * @since 2.5.0
	 * @since 4.5.0 `$username` now accepts an email address.
	 *
	 * @param string $username User's username or email address.
	 * @param string $password User's password.
	 * @return WP_User|WP_Error WP_User object if the credentials are valid,
	 *                          otherwise WP_Error.
	 */
	function wp_authenticate( $username, $password ) {
		$username = sanitize_user( $username );
		$password = trim( $password );

		/**
		 * Filters whether a set of user login credentials are valid.
		 *
		 * A WP_User object is returned if the credentials authenticate a user.
		 * WP_Error or null otherwise.
		 *
		 * @since 2.8.0
		 * @since 4.5.0 `$username` now accepts an email address.
		 *
		 * @param null|WP_User|WP_Error $user     WP_User if the user is authenticated.
		 *                                        WP_Error or null otherwise.
		 * @param string                $username Username or email address.
		 * @param string                $password User password
		 */
		$user = apply_filters( 'authenticate', null, $username, $password );

		if ( null == $user ) {
			// TODO: What should the error message be? (Or would these even happen?)
			// Only needed if all authentication handlers fail to return anything.
			$user = new WP_Error( 'authentication_failed', __( '<strong>Error</strong>: Invalid username, email address or incorrect password.' ) );
		}

		$ignore_codes = array( 'empty_username', 'empty_password' );

		if ( is_wp_error( $user ) && ! in_array( $user->get_error_code(), $ignore_codes, true ) ) {
			$error = $user;

			/**
			 * Fires after a user login has failed.
			 *
			 * @since 2.5.0
			 * @since 4.5.0 The value of `$username` can now be an email address.
			 * @since 5.4.0 The `$error` parameter was added.
			 *
			 * @param string   $username Username or email address.
			 * @param WP_Error $error    A WP_Error object with the authentication failure details.
			 */
			do_action( 'wp_login_failed', $username, $error );
		}

		return $user;
	}
endif;

if ( ! function_exists( 'wp_logout' ) ) :
	/**
	 * Log the current user out.
	 *
	 * @since 2.5.0
	 */
	function wp_logout() {
		$user_id = get_current_user_id();

		wp_destroy_current_session();
		wp_clear_auth_cookie();
		wp_set_current_user( 0 );

		/**
		 * Fires after a user is logged out.
		 *
		 * @since 1.5.0
		 * @since 5.5.0 Added the `$user_id` parameter.
		 *
		 * @param int $user_id ID of the user that was logged out.
		 */
		do_action( 'wp_logout', $user_id );
	}
endif;

if ( ! function_exists( 'wp_validate_auth_cookie' ) ) :
	/**
	 * Validates authentication cookie.
	 *
	 * The checks include making sure that the authentication cookie is set and
	 * pulling in the contents (if $cookie is not used).
	 *
	 * Makes sure the cookie is not expired. Verifies the hash in cookie is what is
	 * should be and compares the two.
	 *
	 * @since 2.5.0
	 *
	 * @global int $login_grace_period
	 *
	 * @param string $cookie Optional. If used, will validate contents instead of cookie's.
	 * @param string $scheme Optional. The cookie scheme to use: 'auth', 'secure_auth', or 'logged_in'.
	 * @return int|false User ID if valid cookie, false if invalid.
	 */
	function wp_validate_auth_cookie( $cookie = '', $scheme = '' ) {
		$cookie_elements = wp_parse_auth_cookie( $cookie, $scheme );
		if ( ! $cookie_elements ) {
			/**
			 * Fires if an authentication cookie is malformed.
			 *
			 * @since 2.7.0
			 *
			 * @param string $cookie Malformed auth cookie.
			 * @param string $scheme Authentication scheme. Values include 'auth', 'secure_auth',
			 *                       or 'logged_in'.
			 */
			do_action( 'auth_cookie_malformed', $cookie, $scheme );
			return false;
		}

		$scheme     = $cookie_elements['scheme'];
		$username   = $cookie_elements['username'];
		$hmac       = $cookie_elements['hmac'];
		$token      = $cookie_elements['token'];
		$expired    = $cookie_elements['expiration'];
		$expiration = $cookie_elements['expiration'];

		// Allow a grace period for POST and Ajax requests.
		if ( wp_doing_ajax() || 'POST' === $_SERVER['REQUEST_METHOD'] ) {
			$expired += HOUR_IN_SECONDS;
		}

		// Quick check to see if an honest cookie has expired.
		if ( $expired < time() ) {
			/**
			 * Fires once an authentication cookie has expired.
			 *
			 * @since 2.7.0
			 *
			 * @param string[] $cookie_elements {
			 *     Authentication cookie components. None of the components should be assumed
			 *     to be valid as they come directly from a client-provided cookie value.
			 *
			 *     @type string $username   User's username.
			 *     @type string $expiration The time the cookie expires as a UNIX timestamp.
			 *     @type string $token      User's session token used.
			 *     @type string $hmac       The security hash for the cookie.
			 *     @type string $scheme     The cookie scheme to use.
			 * }
			 */
			do_action( 'auth_cookie_expired', $cookie_elements );
			return false;
		}

		$user = get_user_by( 'login', $username );
		if ( ! $user ) {
			/**
			 * Fires if a bad username is entered in the user authentication process.
			 *
			 * @since 2.7.0
			 *
			 * @param string[] $cookie_elements {
			 *     Authentication cookie components. None of the components should be assumed
			 *     to be valid as they come directly from a client-provided cookie value.
			 *
			 *     @type string $username   User's username.
			 *     @type string $expiration The time the cookie expires as a UNIX timestamp.
			 *     @type string $token      User's session token used.
			 *     @type string $hmac       The security hash for the cookie.
			 *     @type string $scheme     The cookie scheme to use.
			 * }
			 */
			do_action( 'auth_cookie_bad_username', $cookie_elements );
			return false;
		}

		$pass_frag = substr( $user->user_pass, 8, 4 );

		$key = wp_hash( $username . '|' . $pass_frag . '|' . $expiration . '|' . $token, $scheme );

		// If ext/hash is not present, compat.php's hash_hmac() does not support sha256.
		$algo = function_exists( 'hash' ) ? 'sha256' : 'sha1';
		$hash = hash_hmac( $algo, $username . '|' . $expiration . '|' . $token, $key );

		if ( ! hash_equals( $hash, $hmac ) ) {
			/**
			 * Fires if a bad authentication cookie hash is encountered.
			 *
			 * @since 2.7.0
			 *
			 * @param string[] $cookie_elements {
			 *     Authentication cookie components. None of the components should be assumed
			 *     to be valid as they come directly from a client-provided cookie value.
			 *
			 *     @type string $username   User's username.
			 *     @type string $expiration The time the cookie expires as a UNIX timestamp.
			 *     @type string $token      User's session token used.
			 *     @type string $hmac       The security hash for the cookie.
			 *     @type string $scheme     The cookie scheme to use.
			 * }
			 */
			do_action( 'auth_cookie_bad_hash', $cookie_elements );
			return false;
		}

		$manager = WP_Session_Tokens::get_instance( $user->ID );
		if ( ! $manager->verify( $token ) ) {
			/**
			 * Fires if a bad session token is encountered.
			 *
			 * @since 4.0.0
			 *
			 * @param string[] $cookie_elements {
			 *     Authentication cookie components. None of the components should be assumed
			 *     to be valid as they come directly from a client-provided cookie value.
			 *
			 *     @type string $username   User's username.
			 *     @type string $expiration The time the cookie expires as a UNIX timestamp.
			 *     @type string $token      User's session token used.
			 *     @type string $hmac       The security hash for the cookie.
			 *     @type string $scheme     The cookie scheme to use.
			 * }
			 */
			do_action( 'auth_cookie_bad_session_token', $cookie_elements );
			return false;
		}

		// Ajax/POST grace period set above.
		if ( $expiration < time() ) {
			$GLOBALS['login_grace_period'] = 1;
		}

		/**
		 * Fires once an authentication cookie has been validated.
		 *
		 * @since 2.7.0
		 *
		 * @param string[] $cookie_elements {
		 *     Authentication cookie components.
		 *
		 *     @type string $username   User's username.
		 *     @type string $expiration The time the cookie expires as a UNIX timestamp.
		 *     @type string $token      User's session token used.
		 *     @type string $hmac       The security hash for the cookie.
		 *     @type string $scheme     The cookie scheme to use.
		 * }
		 * @param WP_User  $user            User object.
		 */
		do_action( 'auth_cookie_valid', $cookie_elements, $user );

		return $user->ID;
	}
endif;

if ( ! function_exists( 'wp_generate_auth_cookie' ) ) :
	/**
	 * Generates authentication cookie contents.
	 *
	 * @since 2.5.0
	 * @since 4.0.0 The `$token` parameter was added.
	 *
	 * @param int    $user_id    User ID.
	 * @param int    $expiration The time the cookie expires as a UNIX timestamp.
	 * @param string $scheme     Optional. The cookie scheme to use: 'auth', 'secure_auth', or 'logged_in'.
	 *                           Default 'auth'.
	 * @param string $token      User's session token to use for this cookie.
	 * @return string Authentication cookie contents. Empty string if user does not exist.
	 */
	function wp_generate_auth_cookie( $user_id, $expiration, $scheme = 'auth', $token = '' ) {
		$user = get_userdata( $user_id );
		if ( ! $user ) {
			return '';
		}

		if ( ! $token ) {
			$manager = WP_Session_Tokens::get_instance( $user_id );
			$token   = $manager->create( $expiration );
		}

		$pass_frag = substr( $user->user_pass, 8, 4 );

		$key = wp_hash( $user->user_login . '|' . $pass_frag . '|' . $expiration . '|' . $token, $scheme );

		// If ext/hash is not present, compat.php's hash_hmac() does not support sha256.
		$algo = function_exists( 'hash' ) ? 'sha256' : 'sha1';
		$hash = hash_hmac( $algo, $user->user_login . '|' . $expiration . '|' . $token, $key );

		$cookie = $user->user_login . '|' . $expiration . '|' . $token . '|' . $hash;

		/**
		 * Filters the authentication cookie.
		 *
		 * @since 2.5.0
		 * @since 4.0.0 The `$token` parameter was added.
		 *
		 * @param string $cookie     Authentication cookie.
		 * @param int    $user_id    User ID.
		 * @param int    $expiration The time the cookie expires as a UNIX timestamp.
		 * @param string $scheme     Cookie scheme used. Accepts 'auth', 'secure_auth', or 'logged_in'.
		 * @param string $token      User's session token used.
		 */
		return apply_filters( 'auth_cookie', $cookie, $user_id, $expiration, $scheme, $token );
	}
endif;

if ( ! function_exists( 'wp_parse_auth_cookie' ) ) :
	/**
	 * Parses a cookie into its components.
	 *
	 * @since 2.7.0
	 *
	 * @param string $cookie Authentication cookie.
	 * @param string $scheme Optional. The cookie scheme to use: 'auth', 'secure_auth', or 'logged_in'.
	 * @return string[]|false {
	 *     Authentication cookie components. None of the components should be assumed
	 *     to be valid as they come directly from a client-provided cookie value. If
	 *     the cookie value is malformed, false is returned.
	 *
	 *     @type string $username   User's username.
	 *     @type string $expiration The time the cookie expires as a UNIX timestamp.
	 *     @type string $token      User's session token used.
	 *     @type string $hmac       The security hash for the cookie.
	 *     @type string $scheme     The cookie scheme to use.
	 * }
	 */
	function wp_parse_auth_cookie( $cookie = '', $scheme = '' ) {
		if ( empty( $cookie ) ) {
			switch ( $scheme ) {
				case 'auth':
					$cookie_name = AUTH_COOKIE;
					break;
				case 'secure_auth':
					$cookie_name = SECURE_AUTH_COOKIE;
					break;
				case 'logged_in':
					$cookie_name = LOGGED_IN_COOKIE;
					break;
				default:
					if ( is_ssl() ) {
						$cookie_name = SECURE_AUTH_COOKIE;
						$scheme      = 'secure_auth';
					} else {
						$cookie_name = AUTH_COOKIE;
						$scheme      = 'auth';
					}
			}

			if ( empty( $_COOKIE[ $cookie_name ] ) ) {
				return false;
			}
			$cookie = $_COOKIE[ $cookie_name ];
		}

		$cookie_elements = explode( '|', $cookie );
		if ( count( $cookie_elements ) !== 4 ) {
			return false;
		}

		list( $username, $expiration, $token, $hmac ) = $cookie_elements;

		return compact( 'username', 'expiration', 'token', 'hmac', 'scheme' );
	}
endif;

if ( ! function_exists( 'wp_set_auth_cookie' ) ) :
	/**
	 * Sets the authentication cookies based on user ID.
	 *
	 * The $remember parameter increases the time that the cookie will be kept. The
	 * default the cookie is kept without remembering is two days. When $remember is
	 * set, the cookies will be kept for 14 days or two weeks.
	 *
	 * @since 2.5.0
	 * @since 4.3.0 Added the `$token` parameter.
	 *
	 * @param int         $user_id  User ID.
	 * @param bool        $remember Whether to remember the user.
	 * @param bool|string $secure   Whether the auth cookie should only be sent over HTTPS. Default is an empty
	 *                              string which means the value of `is_ssl()` will be used.
	 * @param string      $token    Optional. User's session token to use for this cookie.
	 */
	function wp_set_auth_cookie( $user_id, $remember = false, $secure = '', $token = '' ) {
		if ( $remember ) {
			/**
			 * Filters the duration of the authentication cookie expiration period.
			 *
			 * @since 2.8.0
			 *
			 * @param int  $length   Duration of the expiration period in seconds.
			 * @param int  $user_id  User ID.
			 * @param bool $remember Whether to remember the user login. Default false.
			 */
			$expiration = time() + apply_filters( 'auth_cookie_expiration', 14 * DAY_IN_SECONDS, $user_id, $remember );

			/*
			 * Ensure the browser will continue to send the cookie after the expiration time is reached.
			 * Needed for the login grace period in wp_validate_auth_cookie().
			 */
			$expire = $expiration + ( 12 * HOUR_IN_SECONDS );
		} else {
			/** This filter is documented in wp-includes/pluggable.php */
			$expiration = time() + apply_filters( 'auth_cookie_expiration', 2 * DAY_IN_SECONDS, $user_id, $remember );
			$expire     = 0;
		}

		if ( '' === $secure ) {
			$secure = is_ssl();
		}

		// Front-end cookie is secure when the auth cookie is secure and the site's home URL uses HTTPS.
		$secure_logged_in_cookie = $secure && 'https' === parse_url( get_option( 'home' ), PHP_URL_SCHEME );

		/**
		 * Filters whether the auth cookie should only be sent over HTTPS.
		 *
		 * @since 3.1.0
		 *
		 * @param bool $secure  Whether the cookie should only be sent over HTTPS.
		 * @param int  $user_id User ID.
		 */
		$secure = apply_filters( 'secure_auth_cookie', $secure, $user_id );

		/**
		 * Filters whether the logged in cookie should only be sent over HTTPS.
		 *
		 * @since 3.1.0
		 *
		 * @param bool $secure_logged_in_cookie Whether the logged in cookie should only be sent over HTTPS.
		 * @param int  $user_id                 User ID.
		 * @param bool $secure                  Whether the auth cookie should only be sent over HTTPS.
		 */
		$secure_logged_in_cookie = apply_filters( 'secure_logged_in_cookie', $secure_logged_in_cookie, $user_id, $secure );

		if ( $secure ) {
			$auth_cookie_name = SECURE_AUTH_COOKIE;
			$scheme           = 'secure_auth';
		} else {
			$auth_cookie_name = AUTH_COOKIE;
			$scheme           = 'auth';
		}

		if ( '' === $token ) {
			$manager = WP_Session_Tokens::get_instance( $user_id );
			$token   = $manager->create( $expiration );
		}

		$auth_cookie      = wp_generate_auth_cookie( $user_id, $expiration, $scheme, $token );
		$logged_in_cookie = wp_generate_auth_cookie( $user_id, $expiration, 'logged_in', $token );

		/**
		 * Fires immediately before the authentication cookie is set.
		 *
		 * @since 2.5.0
		 * @since 4.9.0 The `$token` parameter was added.
		 *
		 * @param string $auth_cookie Authentication cookie value.
		 * @param int    $expire      The time the login grace period expires as a UNIX timestamp.
		 *                            Default is 12 hours past the cookie's expiration time.
		 * @param int    $expiration  The time when the authentication cookie expires as a UNIX timestamp.
		 *                            Default is 14 days from now.
		 * @param int    $user_id     User ID.
		 * @param string $scheme      Authentication scheme. Values include 'auth' or 'secure_auth'.
		 * @param string $token       User's session token to use for this cookie.
		 */
		do_action( 'set_auth_cookie', $auth_cookie, $expire, $expiration, $user_id, $scheme, $token );

		/**
		 * Fires immediately before the logged-in authentication cookie is set.
		 *
		 * @since 2.6.0
		 * @since 4.9.0 The `$token` parameter was added.
		 *
		 * @param string $logged_in_cookie The logged-in cookie value.
		 * @param int    $expire           The time the login grace period expires as a UNIX timestamp.
		 *                                 Default is 12 hours past the cookie's expiration time.
		 * @param int    $expiration       The time when the logged-in authentication cookie expires as a UNIX timestamp.
		 *                                 Default is 14 days from now.
		 * @param int    $user_id          User ID.
		 * @param string $scheme           Authentication scheme. Default 'logged_in'.
		 * @param string $token            User's session token to use for this cookie.
		 */
		do_action( 'set_logged_in_cookie', $logged_in_cookie, $expire, $expiration, $user_id, 'logged_in', $token );

		/**
		 * Allows preventing auth cookies from actually being sent to the client.
		 *
		 * @since 4.7.4
		 *
		 * @param bool $send Whether to send auth cookies to the client.
		 */
		if ( ! apply_filters( 'send_auth_cookies', true ) ) {
			return;
		}

		setcookie( $auth_cookie_name, $auth_cookie, $expire, PLUGINS_COOKIE_PATH, COOKIE_DOMAIN, $secure, true );
		setcookie( $auth_cookie_name, $auth_cookie, $expire, ADMIN_COOKIE_PATH, COOKIE_DOMAIN, $secure, true );
		setcookie( LOGGED_IN_COOKIE, $logged_in_cookie, $expire, COOKIEPATH, COOKIE_DOMAIN, $secure_logged_in_cookie, true );
		if ( COOKIEPATH != SITECOOKIEPATH ) {
			setcookie( LOGGED_IN_COOKIE, $logged_in_cookie, $expire, SITECOOKIEPATH, COOKIE_DOMAIN, $secure_logged_in_cookie, true );
		}
	}
endif;

if ( ! function_exists( 'wp_clear_auth_cookie' ) ) :
	/**
	 * Removes all of the cookies associated with authentication.
	 *
	 * @since 2.5.0
	 */
	function wp_clear_auth_cookie() {
		/**
		 * Fires just before the authentication cookies are cleared.
		 *
		 * @since 2.7.0
		 */
		do_action( 'clear_auth_cookie' );

		/** This filter is documented in wp-includes/pluggable.php */
		if ( ! apply_filters( 'send_auth_cookies', true ) ) {
			return;
		}

		// Auth cookies.
		setcookie( AUTH_COOKIE, ' ', time() - YEAR_IN_SECONDS, ADMIN_COOKIE_PATH, COOKIE_DOMAIN );
		setcookie( SECURE_AUTH_COOKIE, ' ', time() - YEAR_IN_SECONDS, ADMIN_COOKIE_PATH, COOKIE_DOMAIN );
		setcookie( AUTH_COOKIE, ' ', time() - YEAR_IN_SECONDS, PLUGINS_COOKIE_PATH, COOKIE_DOMAIN );
		setcookie( SECURE_AUTH_COOKIE, ' ', time() - YEAR_IN_SECONDS, PLUGINS_COOKIE_PATH, COOKIE_DOMAIN );
		setcookie( LOGGED_IN_COOKIE, ' ', time() - YEAR_IN_SECONDS, COOKIEPATH, COOKIE_DOMAIN );
		setcookie( LOGGED_IN_COOKIE, ' ', time() - YEAR_IN_SECONDS, SITECOOKIEPATH, COOKIE_DOMAIN );

		// Settings cookies.
		setcookie( 'wp-settings-' . get_current_user_id(), ' ', time() - YEAR_IN_SECONDS, SITECOOKIEPATH );
		setcookie( 'wp-settings-time-' . get_current_user_id(), ' ', time() - YEAR_IN_SECONDS, SITECOOKIEPATH );

		// Old cookies.
		setcookie( AUTH_COOKIE, ' ', time() - YEAR_IN_SECONDS, COOKIEPATH, COOKIE_DOMAIN );
		setcookie( AUTH_COOKIE, ' ', time() - YEAR_IN_SECONDS, SITECOOKIEPATH, COOKIE_DOMAIN );
		setcookie( SECURE_AUTH_COOKIE, ' ', time() - YEAR_IN_SECONDS, COOKIEPATH, COOKIE_DOMAIN );
		setcookie( SECURE_AUTH_COOKIE, ' ', time() - YEAR_IN_SECONDS, SITECOOKIEPATH, COOKIE_DOMAIN );

		// Even older cookies.
		setcookie( USER_COOKIE, ' ', time() - YEAR_IN_SECONDS, COOKIEPATH, COOKIE_DOMAIN );
		setcookie( PASS_COOKIE, ' ', time() - YEAR_IN_SECONDS, COOKIEPATH, COOKIE_DOMAIN );
		setcookie( USER_COOKIE, ' ', time() - YEAR_IN_SECONDS, SITECOOKIEPATH, COOKIE_DOMAIN );
		setcookie( PASS_COOKIE, ' ', time() - YEAR_IN_SECONDS, SITECOOKIEPATH, COOKIE_DOMAIN );

		// Post password cookie.
		setcookie( 'wp-postpass_' . COOKIEHASH, ' ', time() - YEAR_IN_SECONDS, COOKIEPATH, COOKIE_DOMAIN );
	}
endif;

if ( ! function_exists( 'is_user_logged_in' ) ) :
	/**
	 * Determines whether the current visitor is a logged in user.
	 *
	 * For more information on this and similar theme functions, check out
	 * the {@link https://developer.wordpress.org/themes/basics/conditional-tags/
	 * Conditional Tags} article in the Theme Developer Handbook.
	 *
	 * @since 2.0.0
	 *
	 * @return bool True if user is logged in, false if not logged in.
	 */
	function is_user_logged_in() {
		$user = wp_get_current_user();

		return $user->exists();
	}
endif;

if ( ! function_exists( 'auth_redirect' ) ) :
	/**
	 * Checks if a user is logged in, if not it redirects them to the login page.
	 *
	 * When this code is called from a page, it checks to see if the user viewing the page is logged in.
	 * If the user is not logged in, they are redirected to the login page. The user is redirected
	 * in such a way that, upon logging in, they will be sent directly to the page they were originally
	 * trying to access.
	 *
	 * @since 1.5.0
	 */
	function auth_redirect() {
		$secure = ( is_ssl() || force_ssl_admin() );

		/**
		 * Filters whether to use a secure authentication redirect.
		 *
		 * @since 3.1.0
		 *
		 * @param bool $secure Whether to use a secure authentication redirect. Default false.
		 */
		$secure = apply_filters( 'secure_auth_redirect', $secure );

		// If https is required and request is http, redirect.
		if ( $secure && ! is_ssl() && false !== strpos( $_SERVER['REQUEST_URI'], 'wp-admin' ) ) {
			if ( 0 === strpos( $_SERVER['REQUEST_URI'], 'http' ) ) {
				wp_redirect( set_url_scheme( $_SERVER['REQUEST_URI'], 'https' ) );
				exit;
			} else {
				wp_redirect( 'https://' . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'] );
				exit;
			}
		}

		/**
		 * Filters the authentication redirect scheme.
		 *
		 * @since 2.9.0
		 *
		 * @param string $scheme Authentication redirect scheme. Default empty.
		 */
		$scheme = apply_filters( 'auth_redirect_scheme', '' );

		$user_id = wp_validate_auth_cookie( '', $scheme );
		if ( $user_id ) {
			/**
			 * Fires before the authentication redirect.
			 *
			 * @since 2.8.0
			 *
			 * @param int $user_id User ID.
			 */
			do_action( 'auth_redirect', $user_id );

			// If the user wants ssl but the session is not ssl, redirect.
			if ( ! $secure && get_user_option( 'use_ssl', $user_id ) && false !== strpos( $_SERVER['REQUEST_URI'], 'wp-admin' ) ) {
				if ( 0 === strpos( $_SERVER['REQUEST_URI'], 'http' ) ) {
					wp_redirect( set_url_scheme( $_SERVER['REQUEST_URI'], 'https' ) );
					exit;
				} else {
					wp_redirect( 'https://' . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'] );
					exit;
				}
			}

			return; // The cookie is good, so we're done.
		}

		// The cookie is no good, so force login.
		nocache_headers();

		$redirect = ( strpos( $_SERVER['REQUEST_URI'], '/options.php' ) && wp_get_referer() ) ? wp_get_referer() : set_url_scheme( 'http://' . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'] );

		$login_url = wp_login_url( $redirect, true );

		wp_redirect( $login_url );
		exit;
	}
endif;

if ( ! function_exists( 'check_admin_referer' ) ) :
	/**
	 * Ensures intent by verifying that a user was referred from another admin page with the correct security nonce.
	 *
	 * This function ensures the user intends to perform a given action, which helps protect against clickjacking style
	 * attacks. It verifies intent, not authorisation, therefore it does not verify the user's capabilities. This should
	 * be performed with `current_user_can()` or similar.
	 *
	 * If the nonce value is invalid, the function will exit with an "Are You Sure?" style message.
	 *
	 * @since 1.2.0
	 * @since 2.5.0 The `$query_arg` parameter was added.
	 *
	 * @param int|string $action    The nonce action.
	 * @param string     $query_arg Optional. Key to check for nonce in `$_REQUEST`. Default '_wpnonce'.
	 * @return int|false 1 if the nonce is valid and generated between 0-12 hours ago,
	 *                   2 if the nonce is valid and generated between 12-24 hours ago.
	 *                   False if the nonce is invalid.
	 */
	function check_admin_referer( $action = -1, $query_arg = '_wpnonce' ) {
		if ( -1 === $action ) {
			_doing_it_wrong( __FUNCTION__, __( 'You should specify an action to be verified by using the first parameter.' ), '3.2.0' );
		}

		$adminurl = strtolower( admin_url() );
		$referer  = strtolower( wp_get_referer() );
		$result   = isset( $_REQUEST[ $query_arg ] ) ? wp_verify_nonce( $_REQUEST[ $query_arg ], $action ) : false;

		/**
		 * Fires once the admin request has been validated or not.
		 *
		 * @since 1.5.1
		 *
		 * @param string    $action The nonce action.
		 * @param false|int $result False if the nonce is invalid, 1 if the nonce is valid and generated between
		 *                          0-12 hours ago, 2 if the nonce is valid and generated between 12-24 hours ago.
		 */
		do_action( 'check_admin_referer', $action, $result );

		if ( ! $result && ! ( -1 === $action && strpos( $referer, $adminurl ) === 0 ) ) {
			wp_nonce_ays( $action );
			die();
		}

		return $result;
	}
endif;

if ( ! function_exists( 'check_ajax_referer' ) ) :
	/**
	 * Verifies the Ajax request to prevent processing requests external of the blog.
	 *
	 * @since 2.0.3
	 *
	 * @param int|string   $action    Action nonce.
	 * @param false|string $query_arg Optional. Key to check for the nonce in `$_REQUEST` (since 2.5). If false,
	 *                                `$_REQUEST` values will be evaluated for '_ajax_nonce', and '_wpnonce'
	 *                                (in that order). Default false.
	 * @param bool         $die       Optional. Whether to die early when the nonce cannot be verified.
	 *                                Default true.
	 * @return int|false 1 if the nonce is valid and generated between 0-12 hours ago,
	 *                   2 if the nonce is valid and generated between 12-24 hours ago.
	 *                   False if the nonce is invalid.
	 */
	function check_ajax_referer( $action = -1, $query_arg = false, $die = true ) {
		if ( -1 == $action ) {
			_doing_it_wrong( __FUNCTION__, __( 'You should specify an action to be verified by using the first parameter.' ), '4.7.0' );
		}

		$nonce = '';

		if ( $query_arg && isset( $_REQUEST[ $query_arg ] ) ) {
			$nonce = $_REQUEST[ $query_arg ];
		} elseif ( isset( $_REQUEST['_ajax_nonce'] ) ) {
			$nonce = $_REQUEST['_ajax_nonce'];
		} elseif ( isset( $_REQUEST['_wpnonce'] ) ) {
			$nonce = $_REQUEST['_wpnonce'];
		}

		$result = wp_verify_nonce( $nonce, $action );

		/**
		 * Fires once the Ajax request has been validated or not.
		 *
		 * @since 2.1.0
		 *
		 * @param string    $action The Ajax nonce action.
		 * @param false|int $result False if the nonce is invalid, 1 if the nonce is valid and generated between
		 *                          0-12 hours ago, 2 if the nonce is valid and generated between 12-24 hours ago.
		 */
		do_action( 'check_ajax_referer', $action, $result );

		if ( $die && false === $result ) {
			if ( wp_doing_ajax() ) {
				wp_die( -1, 403 );
			} else {
				die( '-1' );
			}
		}

		return $result;
	}
endif;

if ( ! function_exists( 'wp_redirect' ) ) :
	/**
	 * Redirects to another page.
	 *
	 * Note: wp_redirect() does not exit automatically, and should almost always be
	 * followed by a call to `exit;`:
	 *
	 *     wp_redirect( $url );
	 *     exit;
	 *
	 * Exiting can also be selectively manipulated by using wp_redirect() as a conditional
	 * in conjunction with the {@see 'wp_redirect'} and {@see 'wp_redirect_location'} filters:
	 *
	 *     if ( wp_redirect( $url ) ) {
	 *         exit;
	 *     }
	 *
	 * @since 1.5.1
	 * @since 5.1.0 The `$x_redirect_by` parameter was added.
	 * @since 5.4.0 On invalid status codes, wp_die() is called.
	 *
	 * @global bool $is_IIS
	 *
	 * @param string $location      The path or URL to redirect to.
	 * @param int    $status        Optional. HTTP response status code to use. Default '302' (Moved Temporarily).
	 * @param string $x_redirect_by Optional. The application doing the redirect. Default 'WordPress'.
	 * @return bool False if the redirect was cancelled, true otherwise.
	 */
	function wp_redirect( $location, $status = 302, $x_redirect_by = 'WordPress' ) {
		global $is_IIS;

		/**
		 * Filters the redirect location.
		 *
		 * @since 2.1.0
		 *
		 * @param string $location The path or URL to redirect to.
		 * @param int    $status   The HTTP response status code to use.
		 */
		$location = apply_filters( 'wp_redirect', $location, $status );

		/**
		 * Filters the redirect HTTP response status code to use.
		 *
		 * @since 2.3.0
		 *
		 * @param int    $status   The HTTP response status code to use.
		 * @param string $location The path or URL to redirect to.
		 */
		$status = apply_filters( 'wp_redirect_status', $status, $location );

		if ( ! $location ) {
			return false;
		}

		if ( $status < 300 || 399 < $status ) {
			wp_die( __( 'HTTP redirect status code must be a redirection code, 3xx.' ) );
		}

		$location = wp_sanitize_redirect( $location );

		if ( ! $is_IIS && 'cgi-fcgi' !== PHP_SAPI ) {
			status_header( $status ); // This causes problems on IIS and some FastCGI setups.
		}

		/**
		 * Filters the X-Redirect-By header.
		 *
		 * Allows applications to identify themselves when they're doing a redirect.
		 *
		 * @since 5.1.0
		 *
		 * @param string $x_redirect_by The application doing the redirect.
		 * @param int    $status        Status code to use.
		 * @param string $location      The path to redirect to.
		 */
		$x_redirect_by = apply_filters( 'x_redirect_by', $x_redirect_by, $status, $location );
		if ( is_string( $x_redirect_by ) ) {
			header( "X-Redirect-By: $x_redirect_by" );
		}

		header( "Location: $location", true, $status );

		return true;
	}
endif;

if ( ! function_exists( 'wp_sanitize_redirect' ) ) :
	/**
	 * Sanitizes a URL for use in a redirect.
	 *
	 * @since 2.3.0
	 *
	 * @param string $location The path to redirect to.
	 * @return string Redirect-sanitized URL.
	 */
	function wp_sanitize_redirect( $location ) {
		// Encode spaces.
		$location = str_replace( ' ', '%20', $location );

		$regex    = '/
		(
			(?: [\xC2-\xDF][\x80-\xBF]        # double-byte sequences   110xxxxx 10xxxxxx
			|   \xE0[\xA0-\xBF][\x80-\xBF]    # triple-byte sequences   1110xxxx 10xxxxxx * 2
			|   [\xE1-\xEC][\x80-\xBF]{2}
			|   \xED[\x80-\x9F][\x80-\xBF]
			|   [\xEE-\xEF][\x80-\xBF]{2}
			|   \xF0[\x90-\xBF][\x80-\xBF]{2} # four-byte sequences   11110xxx 10xxxxxx * 3
			|   [\xF1-\xF3][\x80-\xBF]{3}
			|   \xF4[\x80-\x8F][\x80-\xBF]{2}
		){1,40}                              # ...one or more times
		)/x';
		$location = preg_replace_callback( $regex, '_wp_sanitize_utf8_in_redirect', $location );
		$location = preg_replace( '|[^a-z0-9-~+_.?#=&;,/:%!*\[\]()@]|i', '', $location );
		$location = wp_kses_no_null( $location );

		// Remove %0D and %0A from location.
		$strip = array( '%0d', '%0a', '%0D', '%0A' );
		return _deep_replace( $strip, $location );
	}

	/**
	 * URL encode UTF-8 characters in a URL.
	 *
	 * @ignore
	 * @since 4.2.0
	 * @access private
	 *
	 * @see wp_sanitize_redirect()
	 *
	 * @param array $matches RegEx matches against the redirect location.
	 * @return string URL-encoded version of the first RegEx match.
	 */
	function _wp_sanitize_utf8_in_redirect( $matches ) {
		return urlencode( $matches[0] );
	}
endif;

if ( ! function_exists( 'wp_safe_redirect' ) ) :
	/**
	 * Performs a safe (local) redirect, using wp_redirect().
	 *
	 * Checks whether the $location is using an allowed host, if it has an absolute
	 * path. A plugin can therefore set or remove allowed host(s) to or from the
	 * list.
	 *
	 * If the host is not allowed, then the redirect defaults to wp-admin on the siteurl
	 * instead. This prevents malicious redirects which redirect to another host,
	 * but only used in a few places.
	 *
	 * Note: wp_safe_redirect() does not exit automatically, and should almost always be
	 * followed by a call to `exit;`:
	 *
	 *     wp_safe_redirect( $url );
	 *     exit;
	 *
	 * Exiting can also be selectively manipulated by using wp_safe_redirect() as a conditional
	 * in conjunction with the {@see 'wp_redirect'} and {@see 'wp_redirect_location'} filters:
	 *
	 *     if ( wp_safe_redirect( $url ) ) {
	 *         exit;
	 *     }
	 *
	 * @since 2.3.0
	 * @since 5.1.0 The return value from wp_redirect() is now passed on, and the `$x_redirect_by` parameter was added.
	 *
	 * @param string $location      The path or URL to redirect to.
	 * @param int    $status        Optional. HTTP response status code to use. Default '302' (Moved Temporarily).
	 * @param string $x_redirect_by Optional. The application doing the redirect. Default 'WordPress'.
	 * @return bool False if the redirect was cancelled, true otherwise.
	 */
	function wp_safe_redirect( $location, $status = 302, $x_redirect_by = 'WordPress' ) {

		// Need to look at the URL the way it will end up in wp_redirect().
		$location = wp_sanitize_redirect( $location );

		/**
		 * Filters the redirect fallback URL for when the provided redirect is not safe (local).
		 *
		 * @since 4.3.0
		 *
		 * @param string $fallback_url The fallback URL to use by default.
		 * @param int    $status       The HTTP response status code to use.
		 */
		$location = wp_validate_redirect( $location, apply_filters( 'wp_safe_redirect_fallback', admin_url(), $status ) );

		return wp_redirect( $location, $status, $x_redirect_by );
	}
endif;

if ( ! function_exists( 'wp_validate_redirect' ) ) :
	/**
	 * Validates a URL for use in a redirect.
	 *
	 * Checks whether the $location is using an allowed host, if it has an absolute
	 * path. A plugin can therefore set or remove allowed host(s) to or from the
	 * list.
	 *
	 * If the host is not allowed, then the redirect is to $default supplied
	 *
	 * @since 2.8.1
	 *
	 * @param string $location The redirect to validate
	 * @param string $default  The value to return if $location is not allowed
	 * @return string redirect-sanitized URL
	 */
	function wp_validate_redirect( $location, $default = '' ) {
		$location = wp_sanitize_redirect( trim( $location, " \t\n\r\0\x08\x0B" ) );
		// Browsers will assume 'http' is your protocol, and will obey a redirect to a URL starting with '//'.
		if ( '//' === substr( $location, 0, 2 ) ) {
			$location = 'http:' . $location;
		}

		// In PHP 5 parse_url() may fail if the URL query part contains 'http://'.
		// See https://bugs.php.net/bug.php?id=38143
		$cut  = strpos( $location, '?' );
		$test = $cut ? substr( $location, 0, $cut ) : $location;

		$lp = parse_url( $test );

		// Give up if malformed URL.
		if ( false === $lp ) {
			return $default;
		}

		// Allow only 'http' and 'https' schemes. No 'data:', etc.
		if ( isset( $lp['scheme'] ) && ! ( 'http' === $lp['scheme'] || 'https' === $lp['scheme'] ) ) {
			return $default;
		}

		if ( ! isset( $lp['host'] ) && ! empty( $lp['path'] ) && '/' !== $lp['path'][0] ) {
			$path = '';
			if ( ! empty( $_SERVER['REQUEST_URI'] ) ) {
				$path = dirname( parse_url( 'http://placeholder' . $_SERVER['REQUEST_URI'], PHP_URL_PATH ) . '?' );
				$path = wp_normalize_path( $path );
			}
			$location = '/' . ltrim( $path . '/', '/' ) . $location;
		}

		// Reject if certain components are set but host is not.
		// This catches URLs like https:host.com for which parse_url() does not set the host field.
		if ( ! isset( $lp['host'] ) && ( isset( $lp['scheme'] ) || isset( $lp['user'] ) || isset( $lp['pass'] ) || isset( $lp['port'] ) ) ) {
			return $default;
		}

		// Reject malformed components parse_url() can return on odd inputs.
		foreach ( array( 'user', 'pass', 'host' ) as $component ) {
			if ( isset( $lp[ $component ] ) && strpbrk( $lp[ $component ], ':/?#@' ) ) {
				return $default;
			}
		}

		$wpp = parse_url( home_url() );

		/**
		 * Filters the list of allowed hosts to redirect to.
		 *
		 * @since 2.3.0
		 *
		 * @param string[] $hosts An array of allowed host names.
		 * @param string   $host  The host name of the redirect destination; empty string if not set.
		 */
		$allowed_hosts = (array) apply_filters( 'allowed_redirect_hosts', array( $wpp['host'] ), isset( $lp['host'] ) ? $lp['host'] : '' );

		if ( isset( $lp['host'] ) && ( ! in_array( $lp['host'], $allowed_hosts, true ) && strtolower( $wpp['host'] ) !== $lp['host'] ) ) {
			$location = $default;
		}

		return $location;
	}
endif;

if ( ! function_exists( 'wp_notify_postauthor' ) ) :
	/**
	 * Notify an author (and/or others) of a comment/trackback/pingback on a post.
	 *
	 * @since 1.0.0
	 *
	 * @param int|WP_Comment $comment_id Comment ID or WP_Comment object.
	 * @param string         $deprecated Not used
	 * @return bool True on completion. False if no email addresses were specified.
	 */
	function wp_notify_postauthor( $comment_id, $deprecated = null ) {
		if ( null !== $deprecated ) {
			_deprecated_argument( __FUNCTION__, '3.8.0' );
		}

		$comment = get_comment( $comment_id );
		if ( empty( $comment ) || empty( $comment->comment_post_ID ) ) {
			return false;
		}

		$post   = get_post( $comment->comment_post_ID );
		$author = get_userdata( $post->post_author );

		// Who to notify? By default, just the post author, but others can be added.
		$emails = array();
		if ( $author ) {
			$emails[] = $author->user_email;
		}

		/**
		 * Filters the list of email addresses to receive a comment notification.
		 *
		 * By default, only post authors are notified of comments. This filter allows
		 * others to be added.
		 *
		 * @since 3.7.0
		 *
		 * @param string[] $emails     An array of email addresses to receive a comment notification.
		 * @param string   $comment_id The comment ID as a numeric string.
		 */
		$emails = apply_filters( 'comment_notification_recipients', $emails, $comment->comment_ID );
		$emails = array_filter( $emails );

		// If there are no addresses to send the comment to, bail.
		if ( ! count( $emails ) ) {
			return false;
		}

		// Facilitate unsetting below without knowing the keys.
		$emails = array_flip( $emails );

		/**
		 * Filters whether to notify comment authors of their comments on their own posts.
		 *
		 * By default, comment authors aren't notified of their comments on their own
		 * posts. This filter allows you to override that.
		 *
		 * @since 3.8.0
		 *
		 * @param bool   $notify     Whether to notify the post author of their own comment.
		 *                           Default false.
		 * @param string $comment_id The comment ID as a numeric string.
		 */
		$notify_author = apply_filters( 'comment_notification_notify_author', false, $comment->comment_ID );

		// The comment was left by the author.
		if ( $author && ! $notify_author && $comment->user_id == $post->post_author ) {
			unset( $emails[ $author->user_email ] );
		}

		// The author moderated a comment on their own post.
		if ( $author && ! $notify_author && get_current_user_id() == $post->post_author ) {
			unset( $emails[ $author->user_email ] );
		}

		// The post author is no longer a member of the blog.
		if ( $author && ! $notify_author && ! user_can( $post->post_author, 'read_post', $post->ID ) ) {
			unset( $emails[ $author->user_email ] );
		}

		// If there's no email to send the comment to, bail, otherwise flip array back around for use below.
		if ( ! count( $emails ) ) {
			return false;
		} else {
			$emails = array_flip( $emails );
		}

		$switched_locale = switch_to_locale( get_locale() );

		$comment_author_domain = '';
		if ( WP_Http::is_ip_address( $comment->comment_author_IP ) ) {
			$comment_author_domain = gethostbyaddr( $comment->comment_author_IP );
		}

		// The blogname option is escaped with esc_html() on the way into the database in sanitize_option().
		// We want to reverse this for the plain text arena of emails.
		$blogname        = wp_specialchars_decode( get_option( 'blogname' ), ENT_QUOTES );
		$comment_content = wp_specialchars_decode( $comment->comment_content );

		switch ( $comment->comment_type ) {
			case 'trackback':
				/* translators: %s: Post title. */
				$notify_message = sprintf( __( 'New trackback on your post "%s"' ), $post->post_title ) . "\r\n";
				/* translators: 1: Trackback/pingback website name, 2: Website IP address, 3: Website hostname. */
				$notify_message .= sprintf( __( 'Website: %1$s (IP address: %2$s, %3$s)' ), $comment->comment_author, $comment->comment_author_IP, $comment_author_domain ) . "\r\n";
				/* translators: %s: Trackback/pingback/comment author URL. */
				$notify_message .= sprintf( __( 'URL: %s' ), $comment->comment_author_url ) . "\r\n";
				/* translators: %s: Comment text. */
				$notify_message .= sprintf( __( 'Comment: %s' ), "\r\n" . $comment_content ) . "\r\n\r\n";
				$notify_message .= __( 'You can see all trackbacks on this post here:' ) . "\r\n";
				/* translators: Trackback notification email subject. 1: Site title, 2: Post title. */
				$subject = sprintf( __( '[%1$s] Trackback: "%2$s"' ), $blogname, $post->post_title );
				break;

			case 'pingback':
				/* translators: %s: Post title. */
				$notify_message = sprintf( __( 'New pingback on your post "%s"' ), $post->post_title ) . "\r\n";
				/* translators: 1: Trackback/pingback website name, 2: Website IP address, 3: Website hostname. */
				$notify_message .= sprintf( __( 'Website: %1$s (IP address: %2$s, %3$s)' ), $comment->comment_author, $comment->comment_author_IP, $comment_author_domain ) . "\r\n";
				/* translators: %s: Trackback/pingback/comment author URL. */
				$notify_message .= sprintf( __( 'URL: %s' ), $comment->comment_author_url ) . "\r\n";
				/* translators: %s: Comment text. */
				$notify_message .= sprintf( __( 'Comment: %s' ), "\r\n" . $comment_content ) . "\r\n\r\n";
				$notify_message .= __( 'You can see all pingbacks on this post here:' ) . "\r\n";
				/* translators: Pingback notification email subject. 1: Site title, 2: Post title. */
				$subject = sprintf( __( '[%1$s] Pingback: "%2$s"' ), $blogname, $post->post_title );
				break;

			default: // Comments.
				/* translators: %s: Post title. */
				$notify_message = sprintf( __( 'New comment on your post "%s"' ), $post->post_title ) . "\r\n";
				/* translators: 1: Comment author's name, 2: Comment author's IP address, 3: Comment author's hostname. */
				$notify_message .= sprintf( __( 'Author: %1$s (IP address: %2$s, %3$s)' ), $comment->comment_author, $comment->comment_author_IP, $comment_author_domain ) . "\r\n";
				/* translators: %s: Comment author email. */
				$notify_message .= sprintf( __( 'Email: %s' ), $comment->comment_author_email ) . "\r\n";
				/* translators: %s: Trackback/pingback/comment author URL. */
				$notify_message .= sprintf( __( 'URL: %s' ), $comment->comment_author_url ) . "\r\n";

				if ( $comment->comment_parent && user_can( $post->post_author, 'edit_comment', $comment->comment_parent ) ) {
					/* translators: Comment moderation. %s: Parent comment edit URL. */
					$notify_message .= sprintf( __( 'In reply to: %s' ), admin_url( "comment.php?action=editcomment&c={$comment->comment_parent}#wpbody-content" ) ) . "\r\n";
				}

				/* translators: %s: Comment text. */
				$notify_message .= sprintf( __( 'Comment: %s' ), "\r\n" . $comment_content ) . "\r\n\r\n";
				$notify_message .= __( 'You can see all comments on this post here:' ) . "\r\n";
				/* translators: Comment notification email subject. 1: Site title, 2: Post title. */
				$subject = sprintf( __( '[%1$s] Comment: "%2$s"' ), $blogname, $post->post_title );
				break;
		}

		$notify_message .= get_permalink( $comment->comment_post_ID ) . "#comments\r\n\r\n";
		/* translators: %s: Comment URL. */
		$notify_message .= sprintf( __( 'Permalink: %s' ), get_comment_link( $comment ) ) . "\r\n";

		if ( user_can( $post->post_author, 'edit_comment', $comment->comment_ID ) ) {
			if ( EMPTY_TRASH_DAYS ) {
				/* translators: Comment moderation. %s: Comment action URL. */
				$notify_message .= sprintf( __( 'Trash it: %s' ), admin_url( "comment.php?action=trash&c={$comment->comment_ID}#wpbody-content" ) ) . "\r\n";
			} else {
				/* translators: Comment moderation. %s: Comment action URL. */
				$notify_message .= sprintf( __( 'Delete it: %s' ), admin_url( "comment.php?action=delete&c={$comment->comment_ID}#wpbody-content" ) ) . "\r\n";
			}
			/* translators: Comment moderation. %s: Comment action URL. */
			$notify_message .= sprintf( __( 'Spam it: %s' ), admin_url( "comment.php?action=spam&c={$comment->comment_ID}#wpbody-content" ) ) . "\r\n";
		}

		$wp_email = 'wordpress@' . preg_replace( '#^www\.#', '', wp_parse_url( network_home_url(), PHP_URL_HOST ) );

		if ( '' === $comment->comment_author ) {
			$from = "From: \"$blogname\" <$wp_email>";
			if ( '' !== $comment->comment_author_email ) {
				$reply_to = "Reply-To: $comment->comment_author_email";
			}
		} else {
			$from = "From: \"$comment->comment_author\" <$wp_email>";
			if ( '' !== $comment->comment_author_email ) {
				$reply_to = "Reply-To: \"$comment->comment_author_email\" <$comment->comment_author_email>";
			}
		}

		$message_headers = "$from\n"
		. 'Content-Type: text/plain; charset="' . get_option( 'blog_charset' ) . "\"\n";

		if ( isset( $reply_to ) ) {
			$message_headers .= $reply_to . "\n";
		}

		/**
		 * Filters the comment notification email text.
		 *
		 * @since 1.5.2
		 *
		 * @param string $notify_message The comment notification email text.
		 * @param string $comment_id     Comment ID as a numeric string.
		 */
		$notify_message = apply_filters( 'comment_notification_text', $notify_message, $comment->comment_ID );

		/**
		 * Filters the comment notification email subject.
		 *
		 * @since 1.5.2
		 *
		 * @param string $subject    The comment notification email subject.
		 * @param string $comment_id Comment ID as a numeric string.
		 */
		$subject = apply_filters( 'comment_notification_subject', $subject, $comment->comment_ID );

		/**
		 * Filters the comment notification email headers.
		 *
		 * @since 1.5.2
		 *
		 * @param string $message_headers Headers for the comment notification email.
		 * @param string $comment_id      Comment ID as a numeric string.
		 */
		$message_headers = apply_filters( 'comment_notification_headers', $message_headers, $comment->comment_ID );

		foreach ( $emails as $email ) {
			wp_mail( $email, wp_specialchars_decode( $subject ), $notify_message, $message_headers );
		}

		if ( $switched_locale ) {
			restore_previous_locale();
		}

		return true;
	}
endif;

if ( ! function_exists( 'wp_notify_moderator' ) ) :
	/**
	 * Notifies the moderator of the site about a new comment that is awaiting approval.
	 *
	 * @since 1.0.0
	 *
	 * @global wpdb $wpdb WordPress database abstraction object.
	 *
	 * Uses the {@see 'notify_moderator'} filter to determine whether the site moderator
	 * should be notified, overriding the site setting.
	 *
	 * @param int $comment_id Comment ID.
	 * @return true Always returns true.
	 */
	function wp_notify_moderator( $comment_id ) {
		global $wpdb;

		$maybe_notify = get_option( 'moderation_notify' );

		/**
		 * Filters whether to send the site moderator email notifications, overriding the site setting.
		 *
		 * @since 4.4.0
		 *
		 * @param bool $maybe_notify Whether to notify blog moderator.
		 * @param int  $comment_ID   The id of the comment for the notification.
		 */
		$maybe_notify = apply_filters( 'notify_moderator', $maybe_notify, $comment_id );

		if ( ! $maybe_notify ) {
			return true;
		}

		$comment = get_comment( $comment_id );
		$post    = get_post( $comment->comment_post_ID );
		$user    = get_userdata( $post->post_author );
		// Send to the administration and to the post author if the author can modify the comment.
		$emails = array( get_option( 'admin_email' ) );
		if ( $user && user_can( $user->ID, 'edit_comment', $comment_id ) && ! empty( $user->user_email ) ) {
			if ( 0 !== strcasecmp( $user->user_email, get_option( 'admin_email' ) ) ) {
				$emails[] = $user->user_email;
			}
		}

		$switched_locale = switch_to_locale( get_locale() );

		$comment_author_domain = '';
		if ( WP_Http::is_ip_address( $comment->comment_author_IP ) ) {
			$comment_author_domain = gethostbyaddr( $comment->comment_author_IP );
		}

		$comments_waiting = $wpdb->get_var( "SELECT COUNT(*) FROM $wpdb->comments WHERE comment_approved = '0'" );

		// The blogname option is escaped with esc_html() on the way into the database in sanitize_option().
		// We want to reverse this for the plain text arena of emails.
		$blogname        = wp_specialchars_decode( get_option( 'blogname' ), ENT_QUOTES );
		$comment_content = wp_specialchars_decode( $comment->comment_content );

		switch ( $comment->comment_type ) {
			case 'trackback':
				/* translators: %s: Post title. */
				$notify_message  = sprintf( __( 'A new trackback on the post "%s" is waiting for your approval' ), $post->post_title ) . "\r\n";
				$notify_message .= get_permalink( $comment->comment_post_ID ) . "\r\n\r\n";
				/* translators: 1: Trackback/pingback website name, 2: Website IP address, 3: Website hostname. */
				$notify_message .= sprintf( __( 'Website: %1$s (IP address: %2$s, %3$s)' ), $comment->comment_author, $comment->comment_author_IP, $comment_author_domain ) . "\r\n";
				/* translators: %s: Trackback/pingback/comment author URL. */
				$notify_message .= sprintf( __( 'URL: %s' ), $comment->comment_author_url ) . "\r\n";
				$notify_message .= __( 'Trackback excerpt: ' ) . "\r\n" . $comment_content . "\r\n\r\n";
				break;

			case 'pingback':
				/* translators: %s: Post title. */
				$notify_message  = sprintf( __( 'A new pingback on the post "%s" is waiting for your approval' ), $post->post_title ) . "\r\n";
				$notify_message .= get_permalink( $comment->comment_post_ID ) . "\r\n\r\n";
				/* translators: 1: Trackback/pingback website name, 2: Website IP address, 3: Website hostname. */
				$notify_message .= sprintf( __( 'Website: %1$s (IP address: %2$s, %3$s)' ), $comment->comment_author, $comment->comment_author_IP, $comment_author_domain ) . "\r\n";
				/* translators: %s: Trackback/pingback/comment author URL. */
				$notify_message .= sprintf( __( 'URL: %s' ), $comment->comment_author_url ) . "\r\n";
				$notify_message .= __( 'Pingback excerpt: ' ) . "\r\n" . $comment_content . "\r\n\r\n";
				break;

			default: // Comments.
				/* translators: %s: Post title. */
				$notify_message  = sprintf( __( 'A new comment on the post "%s" is waiting for your approval' ), $post->post_title ) . "\r\n";
				$notify_message .= get_permalink( $comment->comment_post_ID ) . "\r\n\r\n";
				/* translators: 1: Comment author's name, 2: Comment author's IP address, 3: Comment author's hostname. */
				$notify_message .= sprintf( __( 'Author: %1$s (IP address: %2$s, %3$s)' ), $comment->comment_author, $comment->comment_author_IP, $comment_author_domain ) . "\r\n";
				/* translators: %s: Comment author email. */
				$notify_message .= sprintf( __( 'Email: %s' ), $comment->comment_author_email ) . "\r\n";
				/* translators: %s: Trackback/pingback/comment author URL. */
				$notify_message .= sprintf( __( 'URL: %s' ), $comment->comment_author_url ) . "\r\n";

				if ( $comment->comment_parent ) {
					/* translators: Comment moderation. %s: Parent comment edit URL. */
					$notify_message .= sprintf( __( 'In reply to: %s' ), admin_url( "comment.php?action=editcomment&c={$comment->comment_parent}#wpbody-content" ) ) . "\r\n";
				}

				/* translators: %s: Comment text. */
				$notify_message .= sprintf( __( 'Comment: %s' ), "\r\n" . $comment_content ) . "\r\n\r\n";
				break;
		}

		/* translators: Comment moderation. %s: Comment action URL. */
		$notify_message .= sprintf( __( 'Approve it: %s' ), admin_url( "comment.php?action=approve&c={$comment_id}#wpbody-content" ) ) . "\r\n";

		if ( EMPTY_TRASH_DAYS ) {
			/* translators: Comment moderation. %s: Comment action URL. */
			$notify_message .= sprintf( __( 'Trash it: %s' ), admin_url( "comment.php?action=trash&c={$comment_id}#wpbody-content" ) ) . "\r\n";
		} else {
			/* translators: Comment moderation. %s: Comment action URL. */
			$notify_message .= sprintf( __( 'Delete it: %s' ), admin_url( "comment.php?action=delete&c={$comment_id}#wpbody-content" ) ) . "\r\n";
		}

		/* translators: Comment moderation. %s: Comment action URL. */
		$notify_message .= sprintf( __( 'Spam it: %s' ), admin_url( "comment.php?action=spam&c={$comment_id}#wpbody-content" ) ) . "\r\n";

		$notify_message .= sprintf(
			/* translators: Comment moderation. %s: Number of comments awaiting approval. */
			_n(
				'Currently %s comment is waiting for approval. Please visit the moderation panel:',
				'Currently %s comments are waiting for approval. Please visit the moderation panel:',
				$comments_waiting
			),
			number_format_i18n( $comments_waiting )
		) . "\r\n";
		$notify_message .= admin_url( 'edit-comments.php?comment_status=moderated#wpbody-content' ) . "\r\n";

		/* translators: Comment moderation notification email subject. 1: Site title, 2: Post title. */
		$subject         = sprintf( __( '[%1$s] Please moderate: "%2$s"' ), $blogname, $post->post_title );
		$message_headers = '';

		/**
		 * Filters the list of recipients for comment moderation emails.
		 *
		 * @since 3.7.0
		 *
		 * @param string[] $emails     List of email addresses to notify for comment moderation.
		 * @param int      $comment_id Comment ID.
		 */
		$emails = apply_filters( 'comment_moderation_recipients', $emails, $comment_id );

		/**
		 * Filters the comment moderation email text.
		 *
		 * @since 1.5.2
		 *
		 * @param string $notify_message Text of the comment moderation email.
		 * @param int    $comment_id     Comment ID.
		 */
		$notify_message = apply_filters( 'comment_moderation_text', $notify_message, $comment_id );

		/**
		 * Filters the comment moderation email subject.
		 *
		 * @since 1.5.2
		 *
		 * @param string $subject    Subject of the comment moderation email.
		 * @param int    $comment_id Comment ID.
		 */
		$subject = apply_filters( 'comment_moderation_subject', $subject, $comment_id );

		/**
		 * Filters the comment moderation email headers.
		 *
		 * @since 2.8.0
		 *
		 * @param string $message_headers Headers for the comment moderation email.
		 * @param int    $comment_id      Comment ID.
		 */
		$message_headers = apply_filters( 'comment_moderation_headers', $message_headers, $comment_id );

		foreach ( $emails as $email ) {
			wp_mail( $email, wp_specialchars_decode( $subject ), $notify_message, $message_headers );
		}

		if ( $switched_locale ) {
			restore_previous_locale();
		}

		return true;
	}
endif;

if ( ! function_exists( 'wp_password_change_notification' ) ) :
	/**
	 * Notify the blog admin of a user changing password, normally via email.
	 *
	 * @since 2.7.0
	 *
	 * @param WP_User $user User object.
	 */
	function wp_password_change_notification( $user ) {
		// Send a copy of password change notification to the admin,
		// but check to see if it's the admin whose password we're changing, and skip this.
		if ( 0 !== strcasecmp( $user->user_email, get_option( 'admin_email' ) ) ) {
			/* translators: %s: User name. */
			$message = sprintf( __( 'Password changed for user: %s' ), $user->user_login ) . "\r\n";
			// The blogname option is escaped with esc_html() on the way into the database in sanitize_option().
			// We want to reverse this for the plain text arena of emails.
			$blogname = wp_specialchars_decode( get_option( 'blogname' ), ENT_QUOTES );

			$wp_password_change_notification_email = array(
				'to'      => get_option( 'admin_email' ),
				/* translators: Password change notification email subject. %s: Site title. */
				'subject' => __( '[%s] Password Changed' ),
				'message' => $message,
				'headers' => '',
			);

			/**
			 * Filters the contents of the password change notification email sent to the site admin.
			 *
			 * @since 4.9.0
			 *
			 * @param array   $wp_password_change_notification_email {
			 *     Used to build wp_mail().
			 *
			 *     @type string $to      The intended recipient - site admin email address.
			 *     @type string $subject The subject of the email.
			 *     @type string $message The body of the email.
			 *     @type string $headers The headers of the email.
			 * }
			 * @param WP_User $user     User object for user whose password was changed.
			 * @param string  $blogname The site title.
			 */
			$wp_password_change_notification_email = apply_filters( 'wp_password_change_notification_email', $wp_password_change_notification_email, $user, $blogname );

			wp_mail(
				$wp_password_change_notification_email['to'],
				wp_specialchars_decode( sprintf( $wp_password_change_notification_email['subject'], $blogname ) ),
				$wp_password_change_notification_email['message'],
				$wp_password_change_notification_email['headers']
			);
		}
	}
endif;

if ( ! function_exists( 'wp_new_user_notification' ) ) :
	/**
	 * Email login credentials to a newly-registered user.
	 *
	 * A new user registration notification is also sent to admin email.
	 *
	 * @since 2.0.0
	 * @since 4.3.0 The `$plaintext_pass` parameter was changed to `$notify`.
	 * @since 4.3.1 The `$plaintext_pass` parameter was deprecated. `$notify` added as a third parameter.
	 * @since 4.6.0 The `$notify` parameter accepts 'user' for sending notification only to the user created.
	 *
	 * @param int    $user_id    User ID.
	 * @param null   $deprecated Not used (argument deprecated).
	 * @param string $notify     Optional. Type of notification that should happen. Accepts 'admin' or an empty
	 *                           string (admin only), 'user', or 'both' (admin and user). Default empty.
	 */
	function wp_new_user_notification( $user_id, $deprecated = null, $notify = '' ) {
		if ( null !== $deprecated ) {
			_deprecated_argument( __FUNCTION__, '4.3.1' );
		}

		// Accepts only 'user', 'admin' , 'both' or default '' as $notify.
		if ( ! in_array( $notify, array( 'user', 'admin', 'both', '' ), true ) ) {
			return;
		}

		$user = get_userdata( $user_id );

		// The blogname option is escaped with esc_html() on the way into the database in sanitize_option().
		// We want to reverse this for the plain text arena of emails.
		$blogname = wp_specialchars_decode( get_option( 'blogname' ), ENT_QUOTES );

		if ( 'user' !== $notify ) {
			$switched_locale = switch_to_locale( get_locale() );

			/* translators: %s: Site title. */
			$message = sprintf( __( 'New user registration on your site %s:' ), $blogname ) . "\r\n\r\n";
			/* translators: %s: User login. */
			$message .= sprintf( __( 'Username: %s' ), $user->user_login ) . "\r\n\r\n";
			/* translators: %s: User email address. */
			$message .= sprintf( __( 'Email: %s' ), $user->user_email ) . "\r\n";

			$wp_new_user_notification_email_admin = array(
				'to'      => get_option( 'admin_email' ),
				/* translators: New user registration notification email subject. %s: Site title. */
				'subject' => __( '[%s] New User Registration' ),
				'message' => $message,
				'headers' => '',
			);

			/**
			 * Filters the contents of the new user notification email sent to the site admin.
			 *
			 * @since 4.9.0
			 *
			 * @param array   $wp_new_user_notification_email_admin {
			 *     Used to build wp_mail().
			 *
			 *     @type string $to      The intended recipient - site admin email address.
			 *     @type string $subject The subject of the email.
			 *     @type string $message The body of the email.
			 *     @type string $headers The headers of the email.
			 * }
			 * @param WP_User $user     User object for new user.
			 * @param string  $blogname The site title.
			 */
			$wp_new_user_notification_email_admin = apply_filters( 'wp_new_user_notification_email_admin', $wp_new_user_notification_email_admin, $user, $blogname );

			wp_mail(
				$wp_new_user_notification_email_admin['to'],
				wp_specialchars_decode( sprintf( $wp_new_user_notification_email_admin['subject'], $blogname ) ),
				$wp_new_user_notification_email_admin['message'],
				$wp_new_user_notification_email_admin['headers']
			);

			if ( $switched_locale ) {
				restore_previous_locale();
			}
		}

		// `$deprecated` was pre-4.3 `$plaintext_pass`. An empty `$plaintext_pass` didn't sent a user notification.
		if ( 'admin' === $notify || ( empty( $deprecated ) && empty( $notify ) ) ) {
			return;
		}

		$key = get_password_reset_key( $user );
		if ( is_wp_error( $key ) ) {
			return;
		}

		$switched_locale = switch_to_locale( get_user_locale( $user ) );

		/* translators: %s: User login. */
		$message  = sprintf( __( 'Username: %s' ), $user->user_login ) . "\r\n\r\n";
		$message .= __( 'To set your password, visit the following address:' ) . "\r\n\r\n";
		$message .= network_site_url( "wp-login.php?action=rp&key=$key&login=" . rawurlencode( $user->user_login ), 'login' ) . "\r\n\r\n";

		$message .= wp_login_url() . "\r\n";

		$wp_new_user_notification_email = array(
			'to'      => $user->user_email,
			/* translators: Login details notification email subject. %s: Site title. */
			'subject' => __( '[%s] Login Details' ),
			'message' => $message,
			'headers' => '',
		);

		/**
		 * Filters the contents of the new user notification email sent to the new user.
		 *
		 * @since 4.9.0
		 *
		 * @param array   $wp_new_user_notification_email {
		 *     Used to build wp_mail().
		 *
		 *     @type string $to      The intended recipient - New user email address.
		 *     @type string $subject The subject of the email.
		 *     @type string $message The body of the email.
		 *     @type string $headers The headers of the email.
		 * }
		 * @param WP_User $user     User object for new user.
		 * @param string  $blogname The site title.
		 */
		$wp_new_user_notification_email = apply_filters( 'wp_new_user_notification_email', $wp_new_user_notification_email, $user, $blogname );

		wp_mail(
			$wp_new_user_notification_email['to'],
			wp_specialchars_decode( sprintf( $wp_new_user_notification_email['subject'], $blogname ) ),
			$wp_new_user_notification_email['message'],
			$wp_new_user_notification_email['headers']
		);

		if ( $switched_locale ) {
			restore_previous_locale();
		}
	}
endif;

if ( ! function_exists( 'wp_nonce_tick' ) ) :
	/**
	 * Returns the time-dependent variable for nonce creation.
	 *
	 * A nonce has a lifespan of two ticks. Nonces in their second tick may be
	 * updated, e.g. by autosave.
	 *
	 * @since 2.5.0
	 *
	 * @return float Float value rounded up to the next highest integer.
	 */
	function wp_nonce_tick() {
		/**
		 * Filters the lifespan of nonces in seconds.
		 *
		 * @since 2.5.0
		 *
		 * @param int $lifespan Lifespan of nonces in seconds. Default 86,400 seconds, or one day.
		 */
		$nonce_life = apply_filters( 'nonce_life', DAY_IN_SECONDS );

		return ceil( time() / ( $nonce_life / 2 ) );
	}
endif;

if ( ! function_exists( 'wp_verify_nonce' ) ) :
	/**
	 * Verifies that a correct security nonce was used with time limit.
	 *
	 * A nonce is valid for 24 hours (by default).
	 *
	 * @since 2.0.3
	 *
	 * @param string     $nonce  Nonce value that was used for verification, usually via a form field.
	 * @param string|int $action Should give context to what is taking place and be the same when nonce was created.
	 * @return int|false 1 if the nonce is valid and generated between 0-12 hours ago,
	 *                   2 if the nonce is valid and generated between 12-24 hours ago.
	 *                   False if the nonce is invalid.
	 */
	function wp_verify_nonce( $nonce, $action = -1 ) {
		$nonce = (string) $nonce;
		$user  = wp_get_current_user();
		$uid   = (int) $user->ID;
		if ( ! $uid ) {
			/**
			 * Filters whether the user who generated the nonce is logged out.
			 *
			 * @since 3.5.0
			 *
			 * @param int    $uid    ID of the nonce-owning user.
			 * @param string $action The nonce action.
			 */
			$uid = apply_filters( 'nonce_user_logged_out', $uid, $action );
		}

		if ( empty( $nonce ) ) {
			return false;
		}

		$token = wp_get_session_token();
		$i     = wp_nonce_tick();

		// Nonce generated 0-12 hours ago.
		$expected = substr( wp_hash( $i . '|' . $action . '|' . $uid . '|' . $token, 'nonce' ), -12, 10 );
		if ( hash_equals( $expected, $nonce ) ) {
			return 1;
		}

		// Nonce generated 12-24 hours ago.
		$expected = substr( wp_hash( ( $i - 1 ) . '|' . $action . '|' . $uid . '|' . $token, 'nonce' ), -12, 10 );
		if ( hash_equals( $expected, $nonce ) ) {
			return 2;
		}

		/**
		 * Fires when nonce verification fails.
		 *
		 * @since 4.4.0
		 *
		 * @param string     $nonce  The invalid nonce.
		 * @param string|int $action The nonce action.
		 * @param WP_User    $user   The current user object.
		 * @param string     $token  The user's session token.
		 */
		do_action( 'wp_verify_nonce_failed', $nonce, $action, $user, $token );

		// Invalid nonce.
		return false;
	}
endif;

if ( ! function_exists( 'wp_create_nonce' ) ) :
	/**
	 * Creates a cryptographic token tied to a specific action, user, user session,
	 * and window of time.
	 *
	 * @since 2.0.3
	 * @since 4.0.0 Session tokens were integrated with nonce creation
	 *
	 * @param string|int $action Scalar value to add context to the nonce.
	 * @return string The token.
	 */
	function wp_create_nonce( $action = -1 ) {
		$user = wp_get_current_user();
		$uid  = (int) $user->ID;
		if ( ! $uid ) {
			/** This filter is documented in wp-includes/pluggable.php */
			$uid = apply_filters( 'nonce_user_logged_out', $uid, $action );
		}

		$token = wp_get_session_token();
		$i     = wp_nonce_tick();

		return substr( wp_hash( $i . '|' . $action . '|' . $uid . '|' . $token, 'nonce' ), -12, 10 );
	}
endif;

if ( ! function_exists( 'wp_salt' ) ) :
	/**
	 * Returns a salt to add to hashes.
	 *
	 * Salts are created using secret keys. Secret keys are located in two places:
	 * in the database and in the wp-config.php file. The secret key in the database
	 * is randomly generated and will be appended to the secret keys in wp-config.php.
	 *
	 * The secret keys in wp-config.php should be updated to strong, random keys to maximize
	 * security. Below is an example of how the secret key constants are defined.
	 * Do not paste this example directly into wp-config.php. Instead, have a
	 * {@link https://api.wordpress.org/secret-key/1.1/salt/ secret key created} just
	 * for you.
	 *
	 *     define('AUTH_KEY',         ' Xakm<o xQy rw4EMsLKM-?!T+,PFF})H4lzcW57AF0U@N@< >M%G4Yt>f`z]MON');
	 *     define('SECURE_AUTH_KEY',  'LzJ}op]mr|6+![P}Ak:uNdJCJZd>(Hx.-Mh#Tz)pCIU#uGEnfFz|f ;;eU%/U^O~');
	 *     define('LOGGED_IN_KEY',    '|i|Ux`9<p-h$aFf(qnT:sDO:D1P^wZ$$/Ra@miTJi9G;ddp_<q}6H1)o|a +&JCM');
	 *     define('NONCE_KEY',        '%:R{[P|,s.KuMltH5}cI;/k<Gx~j!f0I)m_sIyu+&NJZ)-iO>z7X>QYR0Z_XnZ@|');
	 *     define('AUTH_SALT',        'eZyT)-Naw]F8CwA*VaW#q*|.)g@o}||wf~@C-YSt}(dh_r6EbI#A,y|nU2{B#JBW');
	 *     define('SECURE_AUTH_SALT', '!=oLUTXh,QW=H `}`L|9/^4-3 STz},T(w}W<I`.JjPi)<Bmf1v,HpGe}T1:Xt7n');
	 *     define('LOGGED_IN_SALT',   '+XSqHc;@Q*K_b|Z?NC[3H!!EONbh.n<+=uKR:>*c(u`g~EJBf#8u#R{mUEZrozmm');
	 *     define('NONCE_SALT',       'h`GXHhD>SLWVfg1(1(N{;.V!MoE(SfbA_ksP@&`+AycHcAV$+?@3q+rxV{%^VyKT');
	 *
	 * Salting passwords helps against tools which has stored hashed values of
	 * common dictionary strings. The added values makes it harder to crack.
	 *
	 * @since 2.5.0
	 *
	 * @link https://api.wordpress.org/secret-key/1.1/salt/ Create secrets for wp-config.php
	 *
	 * @param string $scheme Authentication scheme (auth, secure_auth, logged_in, nonce)
	 * @return string Salt value
	 */
	function wp_salt( $scheme = 'auth' ) {
		static $cached_salts = array();
		if ( isset( $cached_salts[ $scheme ] ) ) {
			/**
			 * Filters the WordPress salt.
			 *
			 * @since 2.5.0
			 *
			 * @param string $cached_salt Cached salt for the given scheme.
			 * @param string $scheme      Authentication scheme. Values include 'auth',
			 *                            'secure_auth', 'logged_in', and 'nonce'.
			 */
			return apply_filters( 'salt', $cached_salts[ $scheme ], $scheme );
		}

		static $duplicated_keys;
		if ( null === $duplicated_keys ) {
			$duplicated_keys = array( 'put your unique phrase here' => true );
			foreach ( array( 'AUTH', 'SECURE_AUTH', 'LOGGED_IN', 'NONCE', 'SECRET' ) as $first ) {
				foreach ( array( 'KEY', 'SALT' ) as $second ) {
					if ( ! defined( "{$first}_{$second}" ) ) {
						continue;
					}
					$value                     = constant( "{$first}_{$second}" );
					$duplicated_keys[ $value ] = isset( $duplicated_keys[ $value ] );
				}
			}
		}

		$values = array(
			'key'  => '',
			'salt' => '',
		);
		if ( defined( 'SECRET_KEY' ) && SECRET_KEY && empty( $duplicated_keys[ SECRET_KEY ] ) ) {
			$values['key'] = SECRET_KEY;
		}
		if ( 'auth' === $scheme && defined( 'SECRET_SALT' ) && SECRET_SALT && empty( $duplicated_keys[ SECRET_SALT ] ) ) {
			$values['salt'] = SECRET_SALT;
		}

		if ( in_array( $scheme, array( 'auth', 'secure_auth', 'logged_in', 'nonce' ), true ) ) {
			foreach ( array( 'key', 'salt' ) as $type ) {
				$const = strtoupper( "{$scheme}_{$type}" );
				if ( defined( $const ) && constant( $const ) && empty( $duplicated_keys[ constant( $const ) ] ) ) {
					$values[ $type ] = constant( $const );
				} elseif ( ! $values[ $type ] ) {
					$values[ $type ] = get_site_option( "{$scheme}_{$type}" );
					if ( ! $values[ $type ] ) {
						$values[ $type ] = wp_generate_password( 64, true, true );
						update_site_option( "{$scheme}_{$type}", $values[ $type ] );
					}
				}
			}
		} else {
			if ( ! $values['key'] ) {
				$values['key'] = get_site_option( 'secret_key' );
				if ( ! $values['key'] ) {
					$values['key'] = wp_generate_password( 64, true, true );
					update_site_option( 'secret_key', $values['key'] );
				}
			}
			$values['salt'] = hash_hmac( 'md5', $scheme, $values['key'] );
		}

		$cached_salts[ $scheme ] = $values['key'] . $values['salt'];

		/** This filter is documented in wp-includes/pluggable.php */
		return apply_filters( 'salt', $cached_salts[ $scheme ], $scheme );
	}
endif;

if ( ! function_exists( 'wp_hash' ) ) :
	/**
	 * Get hash of given string.
	 *
	 * @since 2.0.3
	 *
	 * @param string $data   Plain text to hash
	 * @param string $scheme Authentication scheme (auth, secure_auth, logged_in, nonce)
	 * @return string Hash of $data
	 */
	function wp_hash( $data, $scheme = 'auth' ) {
		$salt = wp_salt( $scheme );

		return hash_hmac( 'md5', $data, $salt );
	}
endif;

if ( ! function_exists( 'wp_hash_password' ) ) :
	/**
	 * Create a hash (encrypt) of a plain text password.
	 *
	 * For integration with other applications, this function can be overwritten to
	 * instead use the other package password checking algorithm.
	 *
	 * @since 2.5.0
	 *
	 * @global PasswordHash $wp_hasher PHPass object
	 *
	 * @param string $password Plain text user password to hash
	 * @return string The hash string of the password
	 */
	function wp_hash_password( $password ) {
		global $wp_hasher;

		if ( empty( $wp_hasher ) ) {
			require_once ABSPATH . WPINC . '/class-phpass.php';
			// By default, use the portable hash from phpass.
			$wp_hasher = new PasswordHash( 8, true );
		}

		return $wp_hasher->HashPassword( trim( $password ) );
	}
endif;

if ( ! function_exists( 'wp_check_password' ) ) :
	/**
	 * Checks the plaintext password against the encrypted Password.
	 *
	 * Maintains compatibility between old version and the new cookie authentication
	 * protocol using PHPass library. The $hash parameter is the encrypted password
	 * and the function compares the plain text password when encrypted similarly
	 * against the already encrypted password to see if they match.
	 *
	 * For integration with other applications, this function can be overwritten to
	 * instead use the other package password checking algorithm.
	 *
	 * @since 2.5.0
	 *
	 * @global PasswordHash $wp_hasher PHPass object used for checking the password
	 *                                 against the $hash + $password
	 * @uses PasswordHash::CheckPassword
	 *
	 * @param string     $password Plaintext user's password
	 * @param string     $hash     Hash of the user's password to check against.
	 * @param string|int $user_id  Optional. User ID.
	 * @return bool False, if the $password does not match the hashed password
	 */
	function wp_check_password( $password, $hash, $user_id = '' ) {
		global $wp_hasher;

		// If the hash is still md5...
		if ( strlen( $hash ) <= 32 ) {
			$check = hash_equals( $hash, md5( $password ) );
			if ( $check && $user_id ) {
				// Rehash using new hash.
				wp_set_password( $password, $user_id );
				$hash = wp_hash_password( $password );
			}

			/**
			 * Filters whether the plaintext password matches the encrypted password.
			 *
			 * @since 2.5.0
			 *
			 * @param bool       $check    Whether the passwords match.
			 * @param string     $password The plaintext password.
			 * @param string     $hash     The hashed password.
			 * @param string|int $user_id  User ID. Can be empty.
			 */
			return apply_filters( 'check_password', $check, $password, $hash, $user_id );
		}

		// If the stored hash is longer than an MD5,
		// presume the new style phpass portable hash.
		if ( empty( $wp_hasher ) ) {
			require_once ABSPATH . WPINC . '/class-phpass.php';
			// By default, use the portable hash from phpass.
			$wp_hasher = new PasswordHash( 8, true );
		}

		$check = $wp_hasher->CheckPassword( $password, $hash );

		/** This filter is documented in wp-includes/pluggable.php */
		return apply_filters( 'check_password', $check, $password, $hash, $user_id );
	}
endif;

if ( ! function_exists( 'wp_generate_password' ) ) :
	/**
	 * Generates a random password drawn from the defined set of characters.
	 *
	 * Uses wp_rand() is used to create passwords with far less predictability
	 * than similar native PHP functions like `rand()` or `mt_rand()`.
	 *
	 * @since 2.5.0
	 *
	 * @param int  $length              Optional. The length of password to generate. Default 12.
	 * @param bool $special_chars       Optional. Whether to include standard special characters.
	 *                                  Default true.
	 * @param bool $extra_special_chars Optional. Whether to include other special characters.
	 *                                  Used when generating secret keys and salts. Default false.
	 * @return string The random password.
	 */
	function wp_generate_password( $length = 12, $special_chars = true, $extra_special_chars = false ) {
		$chars = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789';
		if ( $special_chars ) {
			$chars .= '!@#$%^&*()';
		}
		if ( $extra_special_chars ) {
			$chars .= '-_ []{}<>~`+=,.;:/?|';
		}

		$password = '';
		for ( $i = 0; $i < $length; $i++ ) {
			$password .= substr( $chars, wp_rand( 0, strlen( $chars ) - 1 ), 1 );
		}

		/**
		 * Filters the randomly-generated password.
		 *
		 * @since 3.0.0
		 * @since 5.3.0 Added the `$length`, `$special_chars`, and `$extra_special_chars` parameters.
		 *
		 * @param string $password            The generated password.
		 * @param int    $length              The length of password to generate.
		 * @param bool   $special_chars       Whether to include standard special characters.
		 * @param bool   $extra_special_chars Whether to include other special characters.
		 */
		return apply_filters( 'random_password', $password, $length, $special_chars, $extra_special_chars );
	}
endif;

if ( ! function_exists( 'wp_rand' ) ) :
	/**
	 * Generates a random number.
	 *
	 * @since 2.6.2
	 * @since 4.4.0 Uses PHP7 random_int() or the random_compat library if available.
	 *
	 * @global string $rnd_value
	 *
	 * @param int $min Lower limit for the generated number
	 * @param int $max Upper limit for the generated number
	 * @return int A random number between min and max
	 */
	function wp_rand( $min = 0, $max = 0 ) {
		global $rnd_value;

		// Some misconfigured 32-bit environments (Entropy PHP, for example)
		// truncate integers larger than PHP_INT_MAX to PHP_INT_MAX rather than overflowing them to floats.
		$max_random_number = 3000000000 === 2147483647 ? (float) '4294967295' : 4294967295; // 4294967295 = 0xffffffff

		// We only handle ints, floats are truncated to their integer value.
		$min = (int) $min;
		$max = (int) $max;

		// Use PHP's CSPRNG, or a compatible method.
		static $use_random_int_functionality = true;
		if ( $use_random_int_functionality ) {
			try {
				$_max = ( 0 != $max ) ? $max : $max_random_number;
				// wp_rand() can accept arguments in either order, PHP cannot.
				$_max = max( $min, $_max );
				$_min = min( $min, $_max );
				$val  = random_int( $_min, $_max );
				if ( false !== $val ) {
					return absint( $val );
				} else {
					$use_random_int_functionality = false;
				}
			} catch ( Error $e ) {
				$use_random_int_functionality = false;
			} catch ( Exception $e ) {
				$use_random_int_functionality = false;
			}
		}

		// Reset $rnd_value after 14 uses.
		// 32 (md5) + 40 (sha1) + 40 (sha1) / 8 = 14 random numbers from $rnd_value.
		if ( strlen( $rnd_value ) < 8 ) {
			if ( defined( 'WP_SETUP_CONFIG' ) ) {
				static $seed = '';
			} else {
				$seed = get_transient( 'random_seed' );
			}
			$rnd_value  = md5( uniqid( microtime() . mt_rand(), true ) . $seed );
			$rnd_value .= sha1( $rnd_value );
			$rnd_value .= sha1( $rnd_value . $seed );
			$seed       = md5( $seed . $rnd_value );
			if ( ! defined( 'WP_SETUP_CONFIG' ) && ! defined( 'WP_INSTALLING' ) ) {
				set_transient( 'random_seed', $seed );
			}
		}

		// Take the first 8 digits for our value.
		$value = substr( $rnd_value, 0, 8 );

		// Strip the first eight, leaving the remainder for the next call to wp_rand().
		$rnd_value = substr( $rnd_value, 8 );

		$value = abs( hexdec( $value ) );

		// Reduce the value to be within the min - max range.
		if ( 0 != $max ) {
			$value = $min + ( $max - $min + 1 ) * $value / ( $max_random_number + 1 );
		}

		return abs( (int) $value );
	}
endif;

if ( ! function_exists( 'wp_set_password' ) ) :
	/**
	 * Updates the user's password with a new encrypted one.
	 *
	 * For integration with other applications, this function can be overwritten to
	 * instead use the other package password checking algorithm.
	 *
	 * Please note: This function should be used sparingly and is really only meant for single-time
	 * application. Leveraging this improperly in a plugin or theme could result in an endless loop
	 * of password resets if precautions are not taken to ensure it does not execute on every page load.
	 *
	 * @since 2.5.0
	 *
	 * @global wpdb $wpdb WordPress database abstraction object.
	 *
	 * @param string $password The plaintext new user password
	 * @param int    $user_id  User ID
	 */
	function wp_set_password( $password, $user_id ) {
		global $wpdb;

		$hash = wp_hash_password( $password );
		$wpdb->update(
			$wpdb->users,
			array(
				'user_pass'           => $hash,
				'user_activation_key' => '',
			),
			array( 'ID' => $user_id )
		);

		clean_user_cache( $user_id );
	}
endif;

if ( ! function_exists( 'get_avatar' ) ) :
	/**
	 * Retrieve the avatar `<img>` tag for a user, email address, MD5 hash, comment, or post.
	 *
	 * @since 2.5.0
	 * @since 4.2.0 Optional `$args` parameter added.
	 *
	 * @param mixed  $id_or_email The Gravatar to retrieve. Accepts a user_id, gravatar md5 hash,
	 *                            user email, WP_User object, WP_Post object, or WP_Comment object.
	 * @param int    $size        Optional. Height and width of the avatar image file in pixels. Default 96.
	 * @param string $default     Optional. URL for the default image or a default type. Accepts '404'
	 *                            (return a 404 instead of a default image), 'retro' (8bit), 'monsterid'
	 *                            (monster), 'wavatar' (cartoon face), 'indenticon' (the "quilt"),
	 *                            'mystery', 'mm', or 'mysteryman' (The Oyster Man), 'blank' (transparent GIF),
	 *                            or 'gravatar_default' (the Gravatar logo). Default is the value of the
	 *                            'avatar_default' option, with a fallback of 'mystery'.
	 * @param string $alt         Optional. Alternative text to use in img tag. Default empty.
	 * @param array  $args {
	 *     Optional. Extra arguments to retrieve the avatar.
	 *
	 *     @type int          $height        Display height of the avatar in pixels. Defaults to $size.
	 *     @type int          $width         Display width of the avatar in pixels. Defaults to $size.
	 *     @type bool         $force_default Whether to always show the default image, never the Gravatar. Default false.
	 *     @type string       $rating        What rating to display avatars up to. Accepts 'G', 'PG', 'R', 'X', and are
	 *                                       judged in that order. Default is the value of the 'avatar_rating' option.
	 *     @type string       $scheme        URL scheme to use. See set_url_scheme() for accepted values.
	 *                                       Default null.
	 *     @type array|string $class         Array or string of additional classes to add to the img element.
	 *                                       Default null.
	 *     @type bool         $force_display Whether to always show the avatar - ignores the show_avatars option.
	 *                                       Default false.
	 *     @type string       $loading       Value for the `loading` attribute.
	 *                                       Default null.
	 *     @type string       $extra_attr    HTML attributes to insert in the IMG element. Is not sanitized. Default empty.
	 * }
	 * @return string|false `<img>` tag for the user's avatar. False on failure.
	 */
	function get_avatar( $id_or_email, $size = 96, $default = '', $alt = '', $args = null ) {
		$defaults = array(
			// get_avatar_data() args.
			'size'          => 96,
			'height'        => null,
			'width'         => null,
			'default'       => get_option( 'avatar_default', 'mystery' ),
			'force_default' => false,
			'rating'        => get_option( 'avatar_rating' ),
			'scheme'        => null,
			'alt'           => '',
			'class'         => null,
			'force_display' => false,
			'loading'       => null,
			'extra_attr'    => '',
		);

		if ( wp_lazy_loading_enabled( 'img', 'get_avatar' ) ) {
			$defaults['loading'] = wp_get_loading_attr_default( 'get_avatar' );
		}

		if ( empty( $args ) ) {
			$args = array();
		}

		$args['size']    = (int) $size;
		$args['default'] = $default;
		$args['alt']     = $alt;

		$args = wp_parse_args( $args, $defaults );

		if ( empty( $args['height'] ) ) {
			$args['height'] = $args['size'];
		}
		if ( empty( $args['width'] ) ) {
			$args['width'] = $args['size'];
		}

		if ( is_object( $id_or_email ) && isset( $id_or_email->comment_ID ) ) {
			$id_or_email = get_comment( $id_or_email );
		}

		/**
		 * Allows the HTML for a user's avatar to be returned early.
		 *
		 * Returning a non-null value will effectively short-circuit get_avatar(), passing
		 * the value through the {@see 'get_avatar'} filter and returning early.
		 *
		 * @since 4.2.0
		 *
		 * @param string|null $avatar      HTML for the user's avatar. Default null.
		 * @param mixed       $id_or_email The avatar to retrieve. Accepts a user_id, Gravatar MD5 hash,
		 *                                 user email, WP_User object, WP_Post object, or WP_Comment object.
		 * @param array       $args        Arguments passed to get_avatar_url(), after processing.
		 */
		$avatar = apply_filters( 'pre_get_avatar', null, $id_or_email, $args );

		if ( ! is_null( $avatar ) ) {
			/** This filter is documented in wp-includes/pluggable.php */
			return apply_filters( 'get_avatar', $avatar, $id_or_email, $args['size'], $args['default'], $args['alt'], $args );
		}

		if ( ! $args['force_display'] && ! get_option( 'show_avatars' ) ) {
			return false;
		}

		$url2x = get_avatar_url( $id_or_email, array_merge( $args, array( 'size' => $args['size'] * 2 ) ) );

		$args = get_avatar_data( $id_or_email, $args );

		$url = $args['url'];

		if ( ! $url || is_wp_error( $url ) ) {
			return false;
		}

		$class = array( 'avatar', 'avatar-' . (int) $args['size'], 'photo' );

		if ( ! $args['found_avatar'] || $args['force_default'] ) {
			$class[] = 'avatar-default';
		}

		if ( $args['class'] ) {
			if ( is_array( $args['class'] ) ) {
				$class = array_merge( $class, $args['class'] );
			} else {
				$class[] = $args['class'];
			}
		}

		// Add `loading` attribute.
		$extra_attr = $args['extra_attr'];
		$loading    = $args['loading'];

		if ( in_array( $loading, array( 'lazy', 'eager' ), true ) && ! preg_match( '/\bloading\s*=/', $extra_attr ) ) {
			if ( ! empty( $extra_attr ) ) {
				$extra_attr .= ' ';
			}

			$extra_attr .= "loading='{$loading}'";
		}

		$avatar = sprintf(
			"<img alt='%s' src='%s' srcset='%s' class='%s' height='%d' width='%d' %s/>",
			esc_attr( $args['alt'] ),
			esc_url( $url ),
			esc_url( $url2x ) . ' 2x',
			esc_attr( implode( ' ', $class ) ),
			(int) $args['height'],
			(int) $args['width'],
			$extra_attr
		);

		/**
		 * Filters the HTML for a user's avatar.
		 *
		 * @since 2.5.0
		 * @since 4.2.0 The `$args` parameter was added.
		 *
		 * @param string $avatar      HTML for the user's avatar.
		 * @param mixed  $id_or_email The avatar to retrieve. Accepts a user_id, Gravatar MD5 hash,
		 *                            user email, WP_User object, WP_Post object, or WP_Comment object.
		 * @param int    $size        Square avatar width and height in pixels to retrieve.
		 * @param string $default     URL for the default image or a default type. Accepts '404', 'retro', 'monsterid',
		 *                            'wavatar', 'indenticon', 'mystery', 'mm', 'mysteryman', 'blank', or 'gravatar_default'.
		 * @param string $alt         Alternative text to use in the avatar image tag.
		 * @param array  $args        Arguments passed to get_avatar_data(), after processing.
		 */
		return apply_filters( 'get_avatar', $avatar, $id_or_email, $args['size'], $args['default'], $args['alt'], $args );
	}
endif;

if ( ! function_exists( 'wp_text_diff' ) ) :
	/**
	 * Displays a human readable HTML representation of the difference between two strings.
	 *
	 * The Diff is available for getting the changes between versions. The output is
	 * HTML, so the primary use is for displaying the changes. If the two strings
	 * are equivalent, then an empty string will be returned.
	 *
	 * @since 2.6.0
	 *
	 * @see wp_parse_args() Used to change defaults to user defined settings.
	 * @uses Text_Diff
	 * @uses WP_Text_Diff_Renderer_Table
	 *
	 * @param string       $left_string  "old" (left) version of string
	 * @param string       $right_string "new" (right) version of string
	 * @param string|array $args {
	 *     Associative array of options to pass to WP_Text_Diff_Renderer_Table().
	 *
	 *     @type string $title           Titles the diff in a manner compatible
	 *                                   with the output. Default empty.
	 *     @type string $title_left      Change the HTML to the left of the title.
	 *                                   Default empty.
	 *     @type string $title_right     Change the HTML to the right of the title.
	 *                                   Default empty.
	 *     @type bool   $show_split_view True for split view (two columns), false for
	 *                                   un-split view (single column). Default true.
	 * }
	 * @return string Empty string if strings are equivalent or HTML with differences.
	 */
	function wp_text_diff( $left_string, $right_string, $args = null ) {
		$defaults = array(
			'title'           => '',
			'title_left'      => '',
			'title_right'     => '',
			'show_split_view' => true,
		);
		$args     = wp_parse_args( $args, $defaults );

		if ( ! class_exists( 'WP_Text_Diff_Renderer_Table', false ) ) {
			require ABSPATH . WPINC . '/wp-diff.php';
		}

		$left_string  = normalize_whitespace( $left_string );
		$right_string = normalize_whitespace( $right_string );

		$left_lines  = explode( "\n", $left_string );
		$right_lines = explode( "\n", $right_string );
		$text_diff   = new Text_Diff( $left_lines, $right_lines );
		$renderer    = new WP_Text_Diff_Renderer_Table( $args );
		$diff        = $renderer->render( $text_diff );

		if ( ! $diff ) {
			return '';
		}

		$is_split_view       = ! empty( $args['show_split_view'] );
		$is_split_view_class = $is_split_view ? ' is-split-view' : '';

		$r = "<table class='diff$is_split_view_class'>\n";

		if ( $args['title'] ) {
			$r .= "<caption class='diff-title'>$args[title]</caption>\n";
		}

		if ( $args['title_left'] || $args['title_right'] ) {
			$r .= '<thead>';
		}

		if ( $args['title_left'] || $args['title_right'] ) {
			$th_or_td_left  = empty( $args['title_left'] ) ? 'td' : 'th';
			$th_or_td_right = empty( $args['title_right'] ) ? 'td' : 'th';

			$r .= "<tr class='diff-sub-title'>\n";
			$r .= "\t<$th_or_td_left>$args[title_left]</$th_or_td_left>\n";
			if ( $is_split_view ) {
				$r .= "\t<$th_or_td_right>$args[title_right]</$th_or_td_right>\n";
			}
			$r .= "</tr>\n";
		}

		if ( $args['title_left'] || $args['title_right'] ) {
			$r .= "</thead>\n";
		}

		$r .= "<tbody>\n$diff\n</tbody>\n";
		$r .= '</table>';

		return $r;
	}
endif;