includes/GlobalFunctions.php

   1 <?php
   2 /**
   3  * Global functions used everywhere.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  */
  22
  23 if ( !defined( 'MEDIAWIKI' ) ) {
  24         die( "This file is part of MediaWiki, it is not a valid entry point" );
  25 }
  26
  27 use MediaWiki\Logger\LoggerFactory;
  28 use MediaWiki\ProcOpenError;
  29 use MediaWiki\Session\SessionManager;
  30 use MediaWiki\MediaWikiServices;
  31 use MediaWiki\Shell\Shell;
  32 use Wikimedia\ScopedCallback;
  33 use Wikimedia\Rdbms\DBReplicationWaitError;
  34
  35 /**
  36  * Load an extension
  37  *
  38  * This queues an extension to be loaded through
  39  * the ExtensionRegistry system.
  40  *
  41  * @param string $ext Name of the extension to load
  42  * @param string|null $path Absolute path of where to find the extension.json file
  43  * @since 1.25
  44  */
  45 function wfLoadExtension( $ext, $path = null ) {
  46         if ( !$path ) {
  47                 global $wgExtensionDirectory;
  48                 $path = "$wgExtensionDirectory/$ext/extension.json";
  49         }
  50         ExtensionRegistry::getInstance()->queue( $path );
  51 }
  52
  53 /**
  54  * Load multiple extensions at once
  55  *
  56  * Same as wfLoadExtension, but more efficient if you
  57  * are loading multiple extensions.
  58  *
  59  * If you want to specify custom paths, you should interact with
  60  * ExtensionRegistry directly.
  61  *
  62  * @see wfLoadExtension
  63  * @param string[] $exts Array of extension names to load
  64  * @since 1.25
  65  */
  66 function wfLoadExtensions( array $exts ) {
  67         global $wgExtensionDirectory;
  68         $registry = ExtensionRegistry::getInstance();
  69         foreach ( $exts as $ext ) {
  70                 $registry->queue( "$wgExtensionDirectory/$ext/extension.json" );
  71         }
  72 }
  73
  74 /**
  75  * Load a skin
  76  *
  77  * @see wfLoadExtension
  78  * @param string $skin Name of the extension to load
  79  * @param string|null $path Absolute path of where to find the skin.json file
  80  * @since 1.25
  81  */
  82 function wfLoadSkin( $skin, $path = null ) {
  83         if ( !$path ) {
  84                 global $wgStyleDirectory;
  85                 $path = "$wgStyleDirectory/$skin/skin.json";
  86         }
  87         ExtensionRegistry::getInstance()->queue( $path );
  88 }
  89
  90 /**
  91  * Load multiple skins at once
  92  *
  93  * @see wfLoadExtensions
  94  * @param string[] $skins Array of extension names to load
  95  * @since 1.25
  96  */
  97 function wfLoadSkins( array $skins ) {
  98         global $wgStyleDirectory;
  99         $registry = ExtensionRegistry::getInstance();
 100         foreach ( $skins as $skin ) {
 101                 $registry->queue( "$wgStyleDirectory/$skin/skin.json" );
 102         }
 103 }
 104
 105 /**
 106  * Like array_diff( $a, $b ) except that it works with two-dimensional arrays.
 107  * @param array $a
 108  * @param array $b
 109  * @return array
 110  */
 111 function wfArrayDiff2( $a, $b ) {
 112         return array_udiff( $a, $b, 'wfArrayDiff2_cmp' );
 113 }
 114
 115 /**
 116  * @param array|string $a
 117  * @param array|string $b
 118  * @return int
 119  */
 120 function wfArrayDiff2_cmp( $a, $b ) {
 121         if ( is_string( $a ) && is_string( $b ) ) {
 122                 return strcmp( $a, $b );
 123         } elseif ( count( $a ) !== count( $b ) ) {
 124                 return count( $a ) < count( $b ) ? -1 : 1;
 125         } else {
 126                 reset( $a );
 127                 reset( $b );
 128                 while ( key( $a ) !== null && key( $b ) !== null ) {
 129                         $valueA = current( $a );
 130                         $valueB = current( $b );
 131                         $cmp = strcmp( $valueA, $valueB );
 132                         if ( $cmp !== 0 ) {
 133                                 return $cmp;
 134                         }
 135                         next( $a );
 136                         next( $b );
 137                 }
 138                 return 0;
 139         }
 140 }
 141
 142 /**
 143  * Like array_filter with ARRAY_FILTER_USE_BOTH, but works pre-5.6.
 144  *
 145  * @param array $arr
 146  * @param callable $callback Will be called with the array value and key (in that order) and
 147  *   should return a bool which will determine whether the array element is kept.
 148  * @return array
 149  */
 150 function wfArrayFilter( array $arr, callable $callback ) {
 151         if ( defined( 'ARRAY_FILTER_USE_BOTH' ) ) {
 152                 return array_filter( $arr, $callback, ARRAY_FILTER_USE_BOTH );
 153         }
 154         $filteredKeys = array_filter( array_keys( $arr ), function ( $key ) use ( $arr, $callback ) {
 155                 return call_user_func( $callback, $arr[$key], $key );
 156         } );
 157         return array_intersect_key( $arr, array_fill_keys( $filteredKeys, true ) );
 158 }
 159
 160 /**
 161  * Like array_filter with ARRAY_FILTER_USE_KEY, but works pre-5.6.
 162  *
 163  * @param array $arr
 164  * @param callable $callback Will be called with the array key and should return a bool which
 165  *   will determine whether the array element is kept.
 166  * @return array
 167  */
 168 function wfArrayFilterByKey( array $arr, callable $callback ) {
 169         return wfArrayFilter( $arr, function ( $val, $key ) use ( $callback ) {
 170                 return call_user_func( $callback, $key );
 171         } );
 172 }
 173
 174 /**
 175  * Appends to second array if $value differs from that in $default
 176  *
 177  * @param string|int $key
 178  * @param mixed $value
 179  * @param mixed $default
 180  * @param array &$changed Array to alter
 181  * @throws MWException
 182  */
 183 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
 184         if ( is_null( $changed ) ) {
 185                 throw new MWException( 'GlobalFunctions::wfAppendToArrayIfNotDefault got null' );
 186         }
 187         if ( $default[$key] !== $value ) {
 188                 $changed[$key] = $value;
 189         }
 190 }
 191
 192 /**
 193  * Merge arrays in the style of getUserPermissionsErrors, with duplicate removal
 194  * e.g.
 195  *     wfMergeErrorArrays(
 196  *       [ [ 'x' ] ],
 197  *       [ [ 'x', '2' ] ],
 198  *       [ [ 'x' ] ],
 199  *       [ [ 'y' ] ]
 200  *     );
 201  * returns:
 202  *     [
 203  *       [ 'x', '2' ],
 204  *       [ 'x' ],
 205  *       [ 'y' ]
 206  *     ]
 207  *
 208  * @param array $array1,...
 209  * @return array
 210  */
 211 function wfMergeErrorArrays( /*...*/ ) {
 212         $args = func_get_args();
 213         $out = [];
 214         foreach ( $args as $errors ) {
 215                 foreach ( $errors as $params ) {
 216                         $originalParams = $params;
 217                         if ( $params[0] instanceof MessageSpecifier ) {
 218                                 $msg = $params[0];
 219                                 $params = array_merge( [ $msg->getKey() ], $msg->getParams() );
 220                         }
 221                         # @todo FIXME: Sometimes get nested arrays for $params,
 222                         # which leads to E_NOTICEs
 223                         $spec = implode( "\t", $params );
 224                         $out[$spec] = $originalParams;
 225                 }
 226         }
 227         return array_values( $out );
 228 }
 229
 230 /**
 231  * Insert array into another array after the specified *KEY*
 232  *
 233  * @param array $array The array.
 234  * @param array $insert The array to insert.
 235  * @param mixed $after The key to insert after
 236  * @return array
 237  */
 238 function wfArrayInsertAfter( array $array, array $insert, $after ) {
 239         // Find the offset of the element to insert after.
 240         $keys = array_keys( $array );
 241         $offsetByKey = array_flip( $keys );
 242
 243         $offset = $offsetByKey[$after];
 244
 245         // Insert at the specified offset
 246         $before = array_slice( $array, 0, $offset + 1, true );
 247         $after = array_slice( $array, $offset + 1, count( $array ) - $offset, true );
 248
 249         $output = $before + $insert + $after;
 250
 251         return $output;
 252 }
 253
 254 /**
 255  * Recursively converts the parameter (an object) to an array with the same data
 256  *
 257  * @param object|array $objOrArray
 258  * @param bool $recursive
 259  * @return array
 260  */
 261 function wfObjectToArray( $objOrArray, $recursive = true ) {
 262         $array = [];
 263         if ( is_object( $objOrArray ) ) {
 264                 $objOrArray = get_object_vars( $objOrArray );
 265         }
 266         foreach ( $objOrArray as $key => $value ) {
 267                 if ( $recursive && ( is_object( $value ) || is_array( $value ) ) ) {
 268                         $value = wfObjectToArray( $value );
 269                 }
 270
 271                 $array[$key] = $value;
 272         }
 273
 274         return $array;
 275 }
 276
 277 /**
 278  * Get a random decimal value between 0 and 1, in a way
 279  * not likely to give duplicate values for any realistic
 280  * number of articles.
 281  *
 282  * @note This is designed for use in relation to Special:RandomPage
 283  *       and the page_random database field.
 284  *
 285  * @return string
 286  */
 287 function wfRandom() {
 288         // The maximum random value is "only" 2^31-1, so get two random
 289         // values to reduce the chance of dupes
 290         $max = mt_getrandmax() + 1;
 291         $rand = number_format( ( mt_rand() * $max + mt_rand() ) / $max / $max, 12, '.', '' );
 292         return $rand;
 293 }
 294
 295 /**
 296  * Get a random string containing a number of pseudo-random hex characters.
 297  *
 298  * @note This is not secure, if you are trying to generate some sort
 299  *       of token please use MWCryptRand instead.
 300  *
 301  * @param int $length The length of the string to generate
 302  * @return string
 303  * @since 1.20
 304  */
 305 function wfRandomString( $length = 32 ) {
 306         $str = '';
 307         for ( $n = 0; $n < $length; $n += 7 ) {
 308                 $str .= sprintf( '%07x', mt_rand() & 0xfffffff );
 309         }
 310         return substr( $str, 0, $length );
 311 }
 312
 313 /**
 314  * We want some things to be included as literal characters in our title URLs
 315  * for prettiness, which urlencode encodes by default.  According to RFC 1738,
 316  * all of the following should be safe:
 317  *
 318  * ;:@&=$-_.+!*'(),
 319  *
 320  * RFC 1738 says ~ is unsafe, however RFC 3986 considers it an unreserved
 321  * character which should not be encoded. More importantly, google chrome
 322  * always converts %7E back to ~, and converting it in this function can
 323  * cause a redirect loop (T105265).
 324  *
 325  * But + is not safe because it's used to indicate a space; &= are only safe in
 326  * paths and not in queries (and we don't distinguish here); ' seems kind of
 327  * scary; and urlencode() doesn't touch -_. to begin with.  Plus, although /
 328  * is reserved, we don't care.  So the list we unescape is:
 329  *
 330  * ;:@$!*(),/~
 331  *
 332  * However, IIS7 redirects fail when the url contains a colon (see T24709),
 333  * so no fancy : for IIS7.
 334  *
 335  * %2F in the page titles seems to fatally break for some reason.
 336  *
 337  * @param string $s
 338  * @return string
 339  */
 340 function wfUrlencode( $s ) {
 341         static $needle;
 342
 343         if ( is_null( $s ) ) {
 344                 $needle = null;
 345                 return '';
 346         }
 347
 348         if ( is_null( $needle ) ) {
 349                 $needle = [ '%3B', '%40', '%24', '%21', '%2A', '%28', '%29', '%2C', '%2F', '%7E' ];
 350                 if ( !isset( $_SERVER['SERVER_SOFTWARE'] ) ||
 351                         ( strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/7' ) === false )
 352                 ) {
 353                         $needle[] = '%3A';
 354                 }
 355         }
 356
 357         $s = urlencode( $s );
 358         $s = str_ireplace(
 359                 $needle,
 360                 [ ';', '@', '$', '!', '*', '(', ')', ',', '/', '~', ':' ],
 361                 $s
 362         );
 363
 364         return $s;
 365 }
 366
 367 /**
 368  * This function takes one or two arrays as input, and returns a CGI-style string, e.g.
 369  * "days=7&limit=100". Options in the first array override options in the second.
 370  * Options set to null or false will not be output.
 371  *
 372  * @param array $array1 ( String|Array )
 373  * @param array|null $array2 ( String|Array )
 374  * @param string $prefix
 375  * @return string
 376  */
 377 function wfArrayToCgi( $array1, $array2 = null, $prefix = '' ) {
 378         if ( !is_null( $array2 ) ) {
 379                 $array1 = $array1 + $array2;
 380         }
 381
 382         $cgi = '';
 383         foreach ( $array1 as $key => $value ) {
 384                 if ( !is_null( $value ) && $value !== false ) {
 385                         if ( $cgi != '' ) {
 386                                 $cgi .= '&';
 387                         }
 388                         if ( $prefix !== '' ) {
 389                                 $key = $prefix . "[$key]";
 390                         }
 391                         if ( is_array( $value ) ) {
 392                                 $firstTime = true;
 393                                 foreach ( $value as $k => $v ) {
 394                                         $cgi .= $firstTime ? '' : '&';
 395                                         if ( is_array( $v ) ) {
 396                                                 $cgi .= wfArrayToCgi( $v, null, $key . "[$k]" );
 397                                         } else {
 398                                                 $cgi .= urlencode( $key . "[$k]" ) . '=' . urlencode( $v );
 399                                         }
 400                                         $firstTime = false;
 401                                 }
 402                         } else {
 403                                 if ( is_object( $value ) ) {
 404                                         $value = $value->__toString();
 405                                 }
 406                                 $cgi .= urlencode( $key ) . '=' . urlencode( $value );
 407                         }
 408                 }
 409         }
 410         return $cgi;
 411 }
 412
 413 /**
 414  * This is the logical opposite of wfArrayToCgi(): it accepts a query string as
 415  * its argument and returns the same string in array form.  This allows compatibility
 416  * with legacy functions that accept raw query strings instead of nice
 417  * arrays.  Of course, keys and values are urldecode()d.
 418  *
 419  * @param string $query Query string
 420  * @return string[] Array version of input
 421  */
 422 function wfCgiToArray( $query ) {
 423         if ( isset( $query[0] ) && $query[0] == '?' ) {
 424                 $query = substr( $query, 1 );
 425         }
 426         $bits = explode( '&', $query );
 427         $ret = [];
 428         foreach ( $bits as $bit ) {
 429                 if ( $bit === '' ) {
 430                         continue;
 431                 }
 432                 if ( strpos( $bit, '=' ) === false ) {
 433                         // Pieces like &qwerty become 'qwerty' => '' (at least this is what php does)
 434                         $key = $bit;
 435                         $value = '';
 436                 } else {
 437                         list( $key, $value ) = explode( '=', $bit );
 438                 }
 439                 $key = urldecode( $key );
 440                 $value = urldecode( $value );
 441                 if ( strpos( $key, '[' ) !== false ) {
 442                         $keys = array_reverse( explode( '[', $key ) );
 443                         $key = array_pop( $keys );
 444                         $temp = $value;
 445                         foreach ( $keys as $k ) {
 446                                 $k = substr( $k, 0, -1 );
 447                                 $temp = [ $k => $temp ];
 448                         }
 449                         if ( isset( $ret[$key] ) ) {
 450                                 $ret[$key] = array_merge( $ret[$key], $temp );
 451                         } else {
 452                                 $ret[$key] = $temp;
 453                         }
 454                 } else {
 455                         $ret[$key] = $value;
 456                 }
 457         }
 458         return $ret;
 459 }
 460
 461 /**
 462  * Append a query string to an existing URL, which may or may not already
 463  * have query string parameters already. If so, they will be combined.
 464  *
 465  * @param string $url
 466  * @param string|string[] $query String or associative array
 467  * @return string
 468  */
 469 function wfAppendQuery( $url, $query ) {
 470         if ( is_array( $query ) ) {
 471                 $query = wfArrayToCgi( $query );
 472         }
 473         if ( $query != '' ) {
 474                 // Remove the fragment, if there is one
 475                 $fragment = false;
 476                 $hashPos = strpos( $url, '#' );
 477                 if ( $hashPos !== false ) {
 478                         $fragment = substr( $url, $hashPos );
 479                         $url = substr( $url, 0, $hashPos );
 480                 }
 481
 482                 // Add parameter
 483                 if ( false === strpos( $url, '?' ) ) {
 484                         $url .= '?';
 485                 } else {
 486                         $url .= '&';
 487                 }
 488                 $url .= $query;
 489
 490                 // Put the fragment back
 491                 if ( $fragment !== false ) {
 492                         $url .= $fragment;
 493                 }
 494         }
 495         return $url;
 496 }
 497
 498 /**
 499  * Expand a potentially local URL to a fully-qualified URL. Assumes $wgServer
 500  * is correct.
 501  *
 502  * The meaning of the PROTO_* constants is as follows:
 503  * PROTO_HTTP: Output a URL starting with http://
 504  * PROTO_HTTPS: Output a URL starting with https://
 505  * PROTO_RELATIVE: Output a URL starting with // (protocol-relative URL)
 506  * PROTO_CURRENT: Output a URL starting with either http:// or https:// , depending
 507  *    on which protocol was used for the current incoming request
 508  * PROTO_CANONICAL: For URLs without a domain, like /w/index.php , use $wgCanonicalServer.
 509  *    For protocol-relative URLs, use the protocol of $wgCanonicalServer
 510  * PROTO_INTERNAL: Like PROTO_CANONICAL, but uses $wgInternalServer instead of $wgCanonicalServer
 511  *
 512  * @todo this won't work with current-path-relative URLs
 513  * like "subdir/foo.html", etc.
 514  *
 515  * @param string $url Either fully-qualified or a local path + query
 516  * @param string|int|null $defaultProto One of the PROTO_* constants. Determines the
 517  *    protocol to use if $url or $wgServer is protocol-relative
 518  * @return string|false Fully-qualified URL, current-path-relative URL or false if
 519  *    no valid URL can be constructed
 520  */
 521 function wfExpandUrl( $url, $defaultProto = PROTO_CURRENT ) {
 522         global $wgServer, $wgCanonicalServer, $wgInternalServer, $wgRequest,
 523                 $wgHttpsPort;
 524         if ( $defaultProto === PROTO_CANONICAL ) {
 525                 $serverUrl = $wgCanonicalServer;
 526         } elseif ( $defaultProto === PROTO_INTERNAL && $wgInternalServer !== false ) {
 527                 // Make $wgInternalServer fall back to $wgServer if not set
 528                 $serverUrl = $wgInternalServer;
 529         } else {
 530                 $serverUrl = $wgServer;
 531                 if ( $defaultProto === PROTO_CURRENT ) {
 532                         $defaultProto = $wgRequest->getProtocol() . '://';
 533                 }
 534         }
 535
 536         // Analyze $serverUrl to obtain its protocol
 537         $bits = wfParseUrl( $serverUrl );
 538         $serverHasProto = $bits && $bits['scheme'] != '';
 539
 540         if ( $defaultProto === PROTO_CANONICAL || $defaultProto === PROTO_INTERNAL ) {
 541                 if ( $serverHasProto ) {
 542                         $defaultProto = $bits['scheme'] . '://';
 543                 } else {
 544                         // $wgCanonicalServer or $wgInternalServer doesn't have a protocol.
 545                         // This really isn't supposed to happen. Fall back to HTTP in this
 546                         // ridiculous case.
 547                         $defaultProto = PROTO_HTTP;
 548                 }
 549         }
 550
 551         $defaultProtoWithoutSlashes = substr( $defaultProto, 0, -2 );
 552
 553         if ( substr( $url, 0, 2 ) == '//' ) {
 554                 $url = $defaultProtoWithoutSlashes . $url;
 555         } elseif ( substr( $url, 0, 1 ) == '/' ) {
 556                 // If $serverUrl is protocol-relative, prepend $defaultProtoWithoutSlashes,
 557                 // otherwise leave it alone.
 558                 $url = ( $serverHasProto ? '' : $defaultProtoWithoutSlashes ) . $serverUrl . $url;
 559         }
 560
 561         $bits = wfParseUrl( $url );
 562
 563         // ensure proper port for HTTPS arrives in URL
 564         // https://phabricator.wikimedia.org/T67184
 565         if ( $defaultProto === PROTO_HTTPS && $wgHttpsPort != 443 ) {
 566                 $bits['port'] = $wgHttpsPort;
 567         }
 568
 569         if ( $bits && isset( $bits['path'] ) ) {
 570                 $bits['path'] = wfRemoveDotSegments( $bits['path'] );
 571                 return wfAssembleUrl( $bits );
 572         } elseif ( $bits ) {
 573                 # No path to expand
 574                 return $url;
 575         } elseif ( substr( $url, 0, 1 ) != '/' ) {
 576                 # URL is a relative path
 577                 return wfRemoveDotSegments( $url );
 578         }
 579
 580         # Expanded URL is not valid.
 581         return false;
 582 }
 583
 584 /**
 585  * This function will reassemble a URL parsed with wfParseURL.  This is useful
 586  * if you need to edit part of a URL and put it back together.
 587  *
 588  * This is the basic structure used (brackets contain keys for $urlParts):
 589  * [scheme][delimiter][user]:[pass]@[host]:[port][path]?[query]#[fragment]
 590  *
 591  * @todo Need to integrate this into wfExpandUrl (see T34168)
 592  *
 593  * @since 1.19
 594  * @param array $urlParts URL parts, as output from wfParseUrl
 595  * @return string URL assembled from its component parts
 596  */
 597 function wfAssembleUrl( $urlParts ) {
 598         $result = '';
 599
 600         if ( isset( $urlParts['delimiter'] ) ) {
 601                 if ( isset( $urlParts['scheme'] ) ) {
 602                         $result .= $urlParts['scheme'];
 603                 }
 604
 605                 $result .= $urlParts['delimiter'];
 606         }
 607
 608         if ( isset( $urlParts['host'] ) ) {
 609                 if ( isset( $urlParts['user'] ) ) {
 610                         $result .= $urlParts['user'];
 611                         if ( isset( $urlParts['pass'] ) ) {
 612                                 $result .= ':' . $urlParts['pass'];
 613                         }
 614                         $result .= '@';
 615                 }
 616
 617                 $result .= $urlParts['host'];
 618
 619                 if ( isset( $urlParts['port'] ) ) {
 620                         $result .= ':' . $urlParts['port'];
 621                 }
 622         }
 623
 624         if ( isset( $urlParts['path'] ) ) {
 625                 $result .= $urlParts['path'];
 626         }
 627
 628         if ( isset( $urlParts['query'] ) ) {
 629                 $result .= '?' . $urlParts['query'];
 630         }
 631
 632         if ( isset( $urlParts['fragment'] ) ) {
 633                 $result .= '#' . $urlParts['fragment'];
 634         }
 635
 636         return $result;
 637 }
 638
 639 /**
 640  * Remove all dot-segments in the provided URL path.  For example,
 641  * '/a/./b/../c/' becomes '/a/c/'.  For details on the algorithm, please see
 642  * RFC3986 section 5.2.4.
 643  *
 644  * @todo Need to integrate this into wfExpandUrl (see T34168)
 645  *
 646  * @param string $urlPath URL path, potentially containing dot-segments
 647  * @return string URL path with all dot-segments removed
 648  */
 649 function wfRemoveDotSegments( $urlPath ) {
 650         $output = '';
 651         $inputOffset = 0;
 652         $inputLength = strlen( $urlPath );
 653
 654         while ( $inputOffset < $inputLength ) {
 655                 $prefixLengthOne = substr( $urlPath, $inputOffset, 1 );
 656                 $prefixLengthTwo = substr( $urlPath, $inputOffset, 2 );
 657                 $prefixLengthThree = substr( $urlPath, $inputOffset, 3 );
 658                 $prefixLengthFour = substr( $urlPath, $inputOffset, 4 );
 659                 $trimOutput = false;
 660
 661                 if ( $prefixLengthTwo == './' ) {
 662                         # Step A, remove leading "./"
 663                         $inputOffset += 2;
 664                 } elseif ( $prefixLengthThree == '../' ) {
 665                         # Step A, remove leading "../"
 666                         $inputOffset += 3;
 667                 } elseif ( ( $prefixLengthTwo == '/.' ) && ( $inputOffset + 2 == $inputLength ) ) {
 668                         # Step B, replace leading "/.$" with "/"
 669                         $inputOffset += 1;
 670                         $urlPath[$inputOffset] = '/';
 671                 } elseif ( $prefixLengthThree == '/./' ) {
 672                         # Step B, replace leading "/./" with "/"
 673                         $inputOffset += 2;
 674                 } elseif ( $prefixLengthThree == '/..' && ( $inputOffset + 3 == $inputLength ) ) {
 675                         # Step C, replace leading "/..$" with "/" and
 676                         # remove last path component in output
 677                         $inputOffset += 2;
 678                         $urlPath[$inputOffset] = '/';
 679                         $trimOutput = true;
 680                 } elseif ( $prefixLengthFour == '/../' ) {
 681                         # Step C, replace leading "/../" with "/" and
 682                         # remove last path component in output
 683                         $inputOffset += 3;
 684                         $trimOutput = true;
 685                 } elseif ( ( $prefixLengthOne == '.' ) && ( $inputOffset + 1 == $inputLength ) ) {
 686                         # Step D, remove "^.$"
 687                         $inputOffset += 1;
 688                 } elseif ( ( $prefixLengthTwo == '..' ) && ( $inputOffset + 2 == $inputLength ) ) {
 689                         # Step D, remove "^..$"
 690                         $inputOffset += 2;
 691                 } else {
 692                         # Step E, move leading path segment to output
 693                         if ( $prefixLengthOne == '/' ) {
 694                                 $slashPos = strpos( $urlPath, '/', $inputOffset + 1 );
 695                         } else {
 696                                 $slashPos = strpos( $urlPath, '/', $inputOffset );
 697                         }
 698                         if ( $slashPos === false ) {
 699                                 $output .= substr( $urlPath, $inputOffset );
 700                                 $inputOffset = $inputLength;
 701                         } else {
 702                                 $output .= substr( $urlPath, $inputOffset, $slashPos - $inputOffset );
 703                                 $inputOffset += $slashPos - $inputOffset;
 704                         }
 705                 }
 706
 707                 if ( $trimOutput ) {
 708                         $slashPos = strrpos( $output, '/' );
 709                         if ( $slashPos === false ) {
 710                                 $output = '';
 711                         } else {
 712                                 $output = substr( $output, 0, $slashPos );
 713                         }
 714                 }
 715         }
 716
 717         return $output;
 718 }
 719
 720 /**
 721  * Returns a regular expression of url protocols
 722  *
 723  * @param bool $includeProtocolRelative If false, remove '//' from the returned protocol list.
 724  *        DO NOT USE this directly, use wfUrlProtocolsWithoutProtRel() instead
 725  * @return string
 726  */
 727 function wfUrlProtocols( $includeProtocolRelative = true ) {
 728         global $wgUrlProtocols;
 729
 730         // Cache return values separately based on $includeProtocolRelative
 731         static $withProtRel = null, $withoutProtRel = null;
 732         $cachedValue = $includeProtocolRelative ? $withProtRel : $withoutProtRel;
 733         if ( !is_null( $cachedValue ) ) {
 734                 return $cachedValue;
 735         }
 736
 737         // Support old-style $wgUrlProtocols strings, for backwards compatibility
 738         // with LocalSettings files from 1.5
 739         if ( is_array( $wgUrlProtocols ) ) {
 740                 $protocols = [];
 741                 foreach ( $wgUrlProtocols as $protocol ) {
 742                         // Filter out '//' if !$includeProtocolRelative
 743                         if ( $includeProtocolRelative || $protocol !== '//' ) {
 744                                 $protocols[] = preg_quote( $protocol, '/' );
 745                         }
 746                 }
 747
 748                 $retval = implode( '|', $protocols );
 749         } else {
 750                 // Ignore $includeProtocolRelative in this case
 751                 // This case exists for pre-1.6 compatibility, and we can safely assume
 752                 // that '//' won't appear in a pre-1.6 config because protocol-relative
 753                 // URLs weren't supported until 1.18
 754                 $retval = $wgUrlProtocols;
 755         }
 756
 757         // Cache return value
 758         if ( $includeProtocolRelative ) {
 759                 $withProtRel = $retval;
 760         } else {
 761                 $withoutProtRel = $retval;
 762         }
 763         return $retval;
 764 }
 765
 766 /**
 767  * Like wfUrlProtocols(), but excludes '//' from the protocol list. Use this if
 768  * you need a regex that matches all URL protocols but does not match protocol-
 769  * relative URLs
 770  * @return string
 771  */
 772 function wfUrlProtocolsWithoutProtRel() {
 773         return wfUrlProtocols( false );
 774 }
 775
 776 /**
 777  * parse_url() work-alike, but non-broken.  Differences:
 778  *
 779  * 1) Does not raise warnings on bad URLs (just returns false).
 780  * 2) Handles protocols that don't use :// (e.g., mailto: and news:, as well as
 781  *    protocol-relative URLs) correctly.
 782  * 3) Adds a "delimiter" element to the array (see (2)).
 783  * 4) Verifies that the protocol is on the $wgUrlProtocols whitelist.
 784  * 5) Rejects some invalid URLs that parse_url doesn't, e.g. the empty string or URLs starting with
 785  *    a line feed character.
 786  *
 787  * @param string $url A URL to parse
 788  * @return string[]|bool Bits of the URL in an associative array, or false on failure.
 789  *   Possible fields:
 790  *   - scheme: URI scheme (protocol), e.g. 'http', 'mailto'. Lowercase, always present, but can
 791  *       be an empty string for protocol-relative URLs.
 792  *   - delimiter: either '://', ':' or '//'. Always present.
 793  *   - host: domain name / IP. Always present, but could be an empty string, e.g. for file: URLs.
 794  *   - user: user name, e.g. for HTTP Basic auth URLs such as http://user:pass@example.com/
 795  *       Missing when there is no username.
 796  *   - pass: password, same as above.
 797  *   - path: path including the leading /. Will be missing when empty (e.g. 'http://example.com')
 798  *   - query: query string (as a string; see wfCgiToArray() for parsing it), can be missing.
 799  *   - fragment: the part after #, can be missing.
 800  */
 801 function wfParseUrl( $url ) {
 802         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
 803
 804         // Protocol-relative URLs are handled really badly by parse_url(). It's so
 805         // bad that the easiest way to handle them is to just prepend 'http:' and
 806         // strip the protocol out later.
 807         $wasRelative = substr( $url, 0, 2 ) == '//';
 808         if ( $wasRelative ) {
 809                 $url = "http:$url";
 810         }
 811         Wikimedia\suppressWarnings();
 812         $bits = parse_url( $url );
 813         Wikimedia\restoreWarnings();
 814         // parse_url() returns an array without scheme for some invalid URLs, e.g.
 815         // parse_url("%0Ahttp://example.com") == [ 'host' => '%0Ahttp', 'path' => 'example.com' ]
 816         if ( !$bits || !isset( $bits['scheme'] ) ) {
 817                 return false;
 818         }
 819
 820         // parse_url() incorrectly handles schemes case-sensitively. Convert it to lowercase.
 821         $bits['scheme'] = strtolower( $bits['scheme'] );
 822
 823         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
 824         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
 825                 $bits['delimiter'] = '://';
 826         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
 827                 $bits['delimiter'] = ':';
 828                 // parse_url detects for news: and mailto: the host part of an url as path
 829                 // We have to correct this wrong detection
 830                 if ( isset( $bits['path'] ) ) {
 831                         $bits['host'] = $bits['path'];
 832                         $bits['path'] = '';
 833                 }
 834         } else {
 835                 return false;
 836         }
 837
 838         /* Provide an empty host for eg. file:/// urls (see T30627) */
 839         if ( !isset( $bits['host'] ) ) {
 840                 $bits['host'] = '';
 841
 842                 // See T47069
 843                 if ( isset( $bits['path'] ) ) {
 844                         /* parse_url loses the third / for file:///c:/ urls (but not on variants) */
 845                         if ( substr( $bits['path'], 0, 1 ) !== '/' ) {
 846                                 $bits['path'] = '/' . $bits['path'];
 847                         }
 848                 } else {
 849                         $bits['path'] = '';
 850                 }
 851         }
 852
 853         // If the URL was protocol-relative, fix scheme and delimiter
 854         if ( $wasRelative ) {
 855                 $bits['scheme'] = '';
 856                 $bits['delimiter'] = '//';
 857         }
 858         return $bits;
 859 }
 860
 861 /**
 862  * Take a URL, make sure it's expanded to fully qualified, and replace any
 863  * encoded non-ASCII Unicode characters with their UTF-8 original forms
 864  * for more compact display and legibility for local audiences.
 865  *
 866  * @todo handle punycode domains too
 867  *
 868  * @param string $url
 869  * @return string
 870  */
 871 function wfExpandIRI( $url ) {
 872         return preg_replace_callback(
 873                 '/((?:%[89A-F][0-9A-F])+)/i',
 874                 'wfExpandIRI_callback',
 875                 wfExpandUrl( $url )
 876         );
 877 }
 878
 879 /**
 880  * Private callback for wfExpandIRI
 881  * @param array $matches
 882  * @return string
 883  */
 884 function wfExpandIRI_callback( $matches ) {
 885         return urldecode( $matches[1] );
 886 }
 887
 888 /**
 889  * Make URL indexes, appropriate for the el_index field of externallinks.
 890  *
 891  * @param string $url
 892  * @return array
 893  */
 894 function wfMakeUrlIndexes( $url ) {
 895         $bits = wfParseUrl( $url );
 896
 897         // Reverse the labels in the hostname, convert to lower case
 898         // For emails reverse domainpart only
 899         if ( $bits['scheme'] == 'mailto' ) {
 900                 $mailparts = explode( '@', $bits['host'], 2 );
 901                 if ( count( $mailparts ) === 2 ) {
 902                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
 903                 } else {
 904                         // No domain specified, don't mangle it
 905                         $domainpart = '';
 906                 }
 907                 $reversedHost = $domainpart . '@' . $mailparts[0];
 908         } else {
 909                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
 910         }
 911         // Add an extra dot to the end
 912         // Why? Is it in wrong place in mailto links?
 913         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
 914                 $reversedHost .= '.';
 915         }
 916         // Reconstruct the pseudo-URL
 917         $prot = $bits['scheme'];
 918         $index = $prot . $bits['delimiter'] . $reversedHost;
 919         // Leave out user and password. Add the port, path, query and fragment
 920         if ( isset( $bits['port'] ) ) {
 921                 $index .= ':' . $bits['port'];
 922         }
 923         if ( isset( $bits['path'] ) ) {
 924                 $index .= $bits['path'];
 925         } else {
 926                 $index .= '/';
 927         }
 928         if ( isset( $bits['query'] ) ) {
 929                 $index .= '?' . $bits['query'];
 930         }
 931         if ( isset( $bits['fragment'] ) ) {
 932                 $index .= '#' . $bits['fragment'];
 933         }
 934
 935         if ( $prot == '' ) {
 936                 return [ "http:$index", "https:$index" ];
 937         } else {
 938                 return [ $index ];
 939         }
 940 }
 941
 942 /**
 943  * Check whether a given URL has a domain that occurs in a given set of domains
 944  * @param string $url
 945  * @param array $domains Array of domains (strings)
 946  * @return bool True if the host part of $url ends in one of the strings in $domains
 947  */
 948 function wfMatchesDomainList( $url, $domains ) {
 949         $bits = wfParseUrl( $url );
 950         if ( is_array( $bits ) && isset( $bits['host'] ) ) {
 951                 $host = '.' . $bits['host'];
 952                 foreach ( (array)$domains as $domain ) {
 953                         $domain = '.' . $domain;
 954                         if ( substr( $host, -strlen( $domain ) ) === $domain ) {
 955                                 return true;
 956                         }
 957                 }
 958         }
 959         return false;
 960 }
 961
 962 /**
 963  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
 964  * In normal operation this is a NOP.
 965  *
 966  * Controlling globals:
 967  * $wgDebugLogFile - points to the log file
 968  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
 969  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
 970  *
 971  * @since 1.25 support for additional context data
 972  *
 973  * @param string $text
 974  * @param string|bool $dest Destination of the message:
 975  *     - 'all': both to the log and HTML (debug toolbar or HTML comments)
 976  *     - 'private': excluded from HTML output
 977  *   For backward compatibility, it can also take a boolean:
 978  *     - true: same as 'all'
 979  *     - false: same as 'private'
 980  * @param array $context Additional logging context data
 981  */
 982 function wfDebug( $text, $dest = 'all', array $context = [] ) {
 983         global $wgDebugRawPage, $wgDebugLogPrefix;
 984         global $wgDebugTimestamps;
 985
 986         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
 987                 return;
 988         }
 989
 990         $text = trim( $text );
 991
 992         if ( $wgDebugTimestamps ) {
 993                 $context['seconds_elapsed'] = sprintf(
 994                         '%6.4f',
 995                         microtime( true ) - $_SERVER['REQUEST_TIME_FLOAT']
 996                 );
 997                 $context['memory_used'] = sprintf(
 998                         '%5.1fM',
 999                         ( memory_get_usage( true ) / ( 1024 * 1024 ) )
1000                 );
1001         }
1002
1003         if ( $wgDebugLogPrefix !== '' ) {
1004                 $context['prefix'] = $wgDebugLogPrefix;
1005         }
1006         $context['private'] = ( $dest === false || $dest === 'private' );
1007
1008         $logger = LoggerFactory::getInstance( 'wfDebug' );
1009         $logger->debug( $text, $context );
1010 }
1011
1012 /**
1013  * Returns true if debug logging should be suppressed if $wgDebugRawPage = false
1014  * @return bool
1015  */
1016 function wfIsDebugRawPage() {
1017         static $cache;
1018         if ( $cache !== null ) {
1019                 return $cache;
1020         }
1021         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
1022         if ( ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' )
1023                 || (
1024                         isset( $_SERVER['SCRIPT_NAME'] )
1025                         && substr( $_SERVER['SCRIPT_NAME'], -8 ) == 'load.php'
1026                 )
1027         ) {
1028                 $cache = true;
1029         } else {
1030                 $cache = false;
1031         }
1032         return $cache;
1033 }
1034
1035 /**
1036  * Send a line giving PHP memory usage.
1037  *
1038  * @param bool $exact Print exact byte values instead of kibibytes (default: false)
1039  */
1040 function wfDebugMem( $exact = false ) {
1041         $mem = memory_get_usage();
1042         if ( !$exact ) {
1043                 $mem = floor( $mem / 1024 ) . ' KiB';
1044         } else {
1045                 $mem .= ' B';
1046         }
1047         wfDebug( "Memory usage: $mem\n" );
1048 }
1049
1050 /**
1051  * Send a line to a supplementary debug log file, if configured, or main debug
1052  * log if not.
1053  *
1054  * To configure a supplementary log file, set $wgDebugLogGroups[$logGroup] to
1055  * a string filename or an associative array mapping 'destination' to the
1056  * desired filename. The associative array may also contain a 'sample' key
1057  * with an integer value, specifying a sampling factor. Sampled log events
1058  * will be emitted with a 1 in N random chance.
1059  *
1060  * @since 1.23 support for sampling log messages via $wgDebugLogGroups.
1061  * @since 1.25 support for additional context data
1062  * @since 1.25 sample behavior dependent on configured $wgMWLoggerDefaultSpi
1063  *
1064  * @param string $logGroup
1065  * @param string $text
1066  * @param string|bool $dest Destination of the message:
1067  *     - 'all': both to the log and HTML (debug toolbar or HTML comments)
1068  *     - 'private': only to the specific log if set in $wgDebugLogGroups and
1069  *       discarded otherwise
1070  *   For backward compatibility, it can also take a boolean:
1071  *     - true: same as 'all'
1072  *     - false: same as 'private'
1073  * @param array $context Additional logging context data
1074  */
1075 function wfDebugLog(
1076         $logGroup, $text, $dest = 'all', array $context = []
1077 ) {
1078         $text = trim( $text );
1079
1080         $logger = LoggerFactory::getInstance( $logGroup );
1081         $context['private'] = ( $dest === false || $dest === 'private' );
1082         $logger->info( $text, $context );
1083 }
1084
1085 /**
1086  * Log for database errors
1087  *
1088  * @since 1.25 support for additional context data
1089  *
1090  * @param string $text Database error message.
1091  * @param array $context Additional logging context data
1092  */
1093 function wfLogDBError( $text, array $context = [] ) {
1094         $logger = LoggerFactory::getInstance( 'wfLogDBError' );
1095         $logger->error( trim( $text ), $context );
1096 }
1097
1098 /**
1099  * Throws a warning that $function is deprecated
1100  *
1101  * @param string $function
1102  * @param string|bool $version Version of MediaWiki that the function
1103  *    was deprecated in (Added in 1.19).
1104  * @param string|bool $component Added in 1.19.
1105  * @param int $callerOffset How far up the call stack is the original
1106  *    caller. 2 = function that called the function that called
1107  *    wfDeprecated (Added in 1.20)
1108  *
1109  * @return null
1110  */
1111 function wfDeprecated( $function, $version = false, $component = false, $callerOffset = 2 ) {
1112         MWDebug::deprecated( $function, $version, $component, $callerOffset + 1 );
1113 }
1114
1115 /**
1116  * Send a warning either to the debug log or in a PHP error depending on
1117  * $wgDevelopmentWarnings. To log warnings in production, use wfLogWarning() instead.
1118  *
1119  * @param string $msg Message to send
1120  * @param int $callerOffset Number of items to go back in the backtrace to
1121  *        find the correct caller (1 = function calling wfWarn, ...)
1122  * @param int $level PHP error level; defaults to E_USER_NOTICE;
1123  *        only used when $wgDevelopmentWarnings is true
1124  */
1125 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
1126         MWDebug::warning( $msg, $callerOffset + 1, $level, 'auto' );
1127 }
1128
1129 /**
1130  * Send a warning as a PHP error and the debug log. This is intended for logging
1131  * warnings in production. For logging development warnings, use WfWarn instead.
1132  *
1133  * @param string $msg Message to send
1134  * @param int $callerOffset Number of items to go back in the backtrace to
1135  *        find the correct caller (1 = function calling wfLogWarning, ...)
1136  * @param int $level PHP error level; defaults to E_USER_WARNING
1137  */
1138 function wfLogWarning( $msg, $callerOffset = 1, $level = E_USER_WARNING ) {
1139         MWDebug::warning( $msg, $callerOffset + 1, $level, 'production' );
1140 }
1141
1142 /**
1143  * Log to a file without getting "file size exceeded" signals.
1144  *
1145  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
1146  * send lines to the specified port, prefixed by the specified prefix and a space.
1147  * @since 1.25 support for additional context data
1148  *
1149  * @param string $text
1150  * @param string $file Filename
1151  * @param array $context Additional logging context data
1152  * @throws MWException
1153  * @deprecated since 1.25 Use \MediaWiki\Logger\LegacyLogger::emit or UDPTransport
1154  */
1155 function wfErrorLog( $text, $file, array $context = [] ) {
1156         wfDeprecated( __METHOD__, '1.25' );
1157         $logger = LoggerFactory::getInstance( 'wfErrorLog' );
1158         $context['destination'] = $file;
1159         $logger->info( trim( $text ), $context );
1160 }
1161
1162 /**
1163  * @todo document
1164  * @todo Move logic to MediaWiki.php
1165  */
1166 function wfLogProfilingData() {
1167         global $wgDebugLogGroups, $wgDebugRawPage;
1168
1169         $context = RequestContext::getMain();
1170         $request = $context->getRequest();
1171
1172         $profiler = Profiler::instance();
1173         $profiler->setContext( $context );
1174         $profiler->logData();
1175
1176         // Send out any buffered statsd metrics as needed
1177         MediaWiki::emitBufferedStatsdData(
1178                 MediaWikiServices::getInstance()->getStatsdDataFactory(),
1179                 $context->getConfig()
1180         );
1181
1182         // Profiling must actually be enabled...
1183         if ( $profiler instanceof ProfilerStub ) {
1184                 return;
1185         }
1186
1187         if ( isset( $wgDebugLogGroups['profileoutput'] )
1188                 && $wgDebugLogGroups['profileoutput'] === false
1189         ) {
1190                 // Explicitly disabled
1191                 return;
1192         }
1193         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
1194                 return;
1195         }
1196
1197         $ctx = [ 'elapsed' => $request->getElapsedTime() ];
1198         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
1199                 $ctx['forwarded_for'] = $_SERVER['HTTP_X_FORWARDED_FOR'];
1200         }
1201         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
1202                 $ctx['client_ip'] = $_SERVER['HTTP_CLIENT_IP'];
1203         }
1204         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
1205                 $ctx['from'] = $_SERVER['HTTP_FROM'];
1206         }
1207         if ( isset( $ctx['forwarded_for'] ) ||
1208                 isset( $ctx['client_ip'] ) ||
1209                 isset( $ctx['from'] ) ) {
1210                 $ctx['proxy'] = $_SERVER['REMOTE_ADDR'];
1211         }
1212
1213         // Don't load $wgUser at this late stage just for statistics purposes
1214         // @todo FIXME: We can detect some anons even if it is not loaded.
1215         // See User::getId()
1216         $user = $context->getUser();
1217         $ctx['anon'] = $user->isItemLoaded( 'id' ) && $user->isAnon();
1218
1219         // Command line script uses a FauxRequest object which does not have
1220         // any knowledge about an URL and throw an exception instead.
1221         try {
1222                 $ctx['url'] = urldecode( $request->getRequestURL() );
1223         } catch ( Exception $ignored ) {
1224                 // no-op
1225         }
1226
1227         $ctx['output'] = $profiler->getOutput();
1228
1229         $log = LoggerFactory::getInstance( 'profileoutput' );
1230         $log->info( "Elapsed: {elapsed}; URL: <{url}>\n{output}", $ctx );
1231 }
1232
1233 /**
1234  * Increment a statistics counter
1235  *
1236  * @param string $key
1237  * @param int $count
1238  * @return void
1239  */
1240 function wfIncrStats( $key, $count = 1 ) {
1241         $stats = MediaWikiServices::getInstance()->getStatsdDataFactory();
1242         $stats->updateCount( $key, $count );
1243 }
1244
1245 /**
1246  * Check whether the wiki is in read-only mode.
1247  *
1248  * @return bool
1249  */
1250 function wfReadOnly() {
1251         return MediaWikiServices::getInstance()->getReadOnlyMode()
1252                 ->isReadOnly();
1253 }
1254
1255 /**
1256  * Check if the site is in read-only mode and return the message if so
1257  *
1258  * This checks wfConfiguredReadOnlyReason() and the main load balancer
1259  * for replica DB lag. This may result in DB connection being made.
1260  *
1261  * @return string|bool String when in read-only mode; false otherwise
1262  */
1263 function wfReadOnlyReason() {
1264         return MediaWikiServices::getInstance()->getReadOnlyMode()
1265                 ->getReason();
1266 }
1267
1268 /**
1269  * Get the value of $wgReadOnly or the contents of $wgReadOnlyFile.
1270  *
1271  * @return string|bool String when in read-only mode; false otherwise
1272  * @since 1.27
1273  */
1274 function wfConfiguredReadOnlyReason() {
1275         return MediaWikiServices::getInstance()->getConfiguredReadOnlyMode()
1276                 ->getReason();
1277 }
1278
1279 /**
1280  * Return a Language object from $langcode
1281  *
1282  * @param Language|string|bool $langcode Either:
1283  *                  - a Language object
1284  *                  - code of the language to get the message for, if it is
1285  *                    a valid code create a language for that language, if
1286  *                    it is a string but not a valid code then make a basic
1287  *                    language object
1288  *                  - a boolean: if it's false then use the global object for
1289  *                    the current user's language (as a fallback for the old parameter
1290  *                    functionality), or if it is true then use global object
1291  *                    for the wiki's content language.
1292  * @return Language
1293  */
1294 function wfGetLangObj( $langcode = false ) {
1295         # Identify which language to get or create a language object for.
1296         # Using is_object here due to Stub objects.
1297         if ( is_object( $langcode ) ) {
1298                 # Great, we already have the object (hopefully)!
1299                 return $langcode;
1300         }
1301
1302         global $wgContLang, $wgLanguageCode;
1303         if ( $langcode === true || $langcode === $wgLanguageCode ) {
1304                 # $langcode is the language code of the wikis content language object.
1305                 # or it is a boolean and value is true
1306                 return $wgContLang;
1307         }
1308
1309         global $wgLang;
1310         if ( $langcode === false || $langcode === $wgLang->getCode() ) {
1311                 # $langcode is the language code of user language object.
1312                 # or it was a boolean and value is false
1313                 return $wgLang;
1314         }
1315
1316         $validCodes = array_keys( Language::fetchLanguageNames() );
1317         if ( in_array( $langcode, $validCodes ) ) {
1318                 # $langcode corresponds to a valid language.
1319                 return Language::factory( $langcode );
1320         }
1321
1322         # $langcode is a string, but not a valid language code; use content language.
1323         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
1324         return $wgContLang;
1325 }
1326
1327 /**
1328  * This is the function for getting translated interface messages.
1329  *
1330  * @see Message class for documentation how to use them.
1331  * @see https://www.mediawiki.org/wiki/Manual:Messages_API
1332  *
1333  * This function replaces all old wfMsg* functions.
1334  *
1335  * @param string|string[]|MessageSpecifier $key Message key, or array of keys, or a MessageSpecifier
1336  * @param mixed $params,... Normal message parameters
1337  * @return Message
1338  *
1339  * @since 1.17
1340  *
1341  * @see Message::__construct
1342  */
1343 function wfMessage( $key /*...*/ ) {
1344         $message = new Message( $key );
1345
1346         // We call Message::params() to reduce code duplication
1347         $params = func_get_args();
1348         array_shift( $params );
1349         if ( $params ) {
1350                 call_user_func_array( [ $message, 'params' ], $params );
1351         }
1352
1353         return $message;
1354 }
1355
1356 /**
1357  * This function accepts multiple message keys and returns a message instance
1358  * for the first message which is non-empty. If all messages are empty then an
1359  * instance of the first message key is returned.
1360  *
1361  * @param string|string[] $keys,... Message keys
1362  * @return Message
1363  *
1364  * @since 1.18
1365  *
1366  * @see Message::newFallbackSequence
1367  */
1368 function wfMessageFallback( /*...*/ ) {
1369         $args = func_get_args();
1370         return call_user_func_array( 'Message::newFallbackSequence', $args );
1371 }
1372
1373 /**
1374  * Replace message parameter keys on the given formatted output.
1375  *
1376  * @param string $message
1377  * @param array $args
1378  * @return string
1379  * @private
1380  */
1381 function wfMsgReplaceArgs( $message, $args ) {
1382         # Fix windows line-endings
1383         # Some messages are split with explode("\n", $msg)
1384         $message = str_replace( "\r", '', $message );
1385
1386         // Replace arguments
1387         if ( is_array( $args ) && $args ) {
1388                 if ( is_array( $args[0] ) ) {
1389                         $args = array_values( $args[0] );
1390                 }
1391                 $replacementKeys = [];
1392                 foreach ( $args as $n => $param ) {
1393                         $replacementKeys['$' . ( $n + 1 )] = $param;
1394                 }
1395                 $message = strtr( $message, $replacementKeys );
1396         }
1397
1398         return $message;
1399 }
1400
1401 /**
1402  * Fetch server name for use in error reporting etc.
1403  * Use real server name if available, so we know which machine
1404  * in a server farm generated the current page.
1405  *
1406  * @return string
1407  */
1408 function wfHostname() {
1409         static $host;
1410         if ( is_null( $host ) ) {
1411                 # Hostname overriding
1412                 global $wgOverrideHostname;
1413                 if ( $wgOverrideHostname !== false ) {
1414                         # Set static and skip any detection
1415                         $host = $wgOverrideHostname;
1416                         return $host;
1417                 }
1418
1419                 if ( function_exists( 'posix_uname' ) ) {
1420                         // This function not present on Windows
1421                         $uname = posix_uname();
1422                 } else {
1423                         $uname = false;
1424                 }
1425                 if ( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1426                         $host = $uname['nodename'];
1427                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1428                         # Windows computer name
1429                         $host = getenv( 'COMPUTERNAME' );
1430                 } else {
1431                         # This may be a virtual server.
1432                         $host = $_SERVER['SERVER_NAME'];
1433                 }
1434         }
1435         return $host;
1436 }
1437
1438 /**
1439  * Returns a script tag that stores the amount of time it took MediaWiki to
1440  * handle the request in milliseconds as 'wgBackendResponseTime'.
1441  *
1442  * If $wgShowHostnames is true, the script will also set 'wgHostname' to the
1443  * hostname of the server handling the request.
1444  *
1445  * @return string
1446  */
1447 function wfReportTime() {
1448         global $wgShowHostnames;
1449
1450         $elapsed = ( microtime( true ) - $_SERVER['REQUEST_TIME_FLOAT'] );
1451         // seconds to milliseconds
1452         $responseTime = round( $elapsed * 1000 );
1453         $reportVars = [ 'wgBackendResponseTime' => $responseTime ];
1454         if ( $wgShowHostnames ) {
1455                 $reportVars['wgHostname'] = wfHostname();
1456         }
1457         return Skin::makeVariablesScript( $reportVars );
1458 }
1459
1460 /**
1461  * Safety wrapper for debug_backtrace().
1462  *
1463  * Will return an empty array if debug_backtrace is disabled, otherwise
1464  * the output from debug_backtrace() (trimmed).
1465  *
1466  * @param int $limit This parameter can be used to limit the number of stack frames returned
1467  *
1468  * @return array Array of backtrace information
1469  */
1470 function wfDebugBacktrace( $limit = 0 ) {
1471         static $disabled = null;
1472
1473         if ( is_null( $disabled ) ) {
1474                 $disabled = !function_exists( 'debug_backtrace' );
1475                 if ( $disabled ) {
1476                         wfDebug( "debug_backtrace() is disabled\n" );
1477                 }
1478         }
1479         if ( $disabled ) {
1480                 return [];
1481         }
1482
1483         if ( $limit ) {
1484                 return array_slice( debug_backtrace( DEBUG_BACKTRACE_PROVIDE_OBJECT, $limit + 1 ), 1 );
1485         } else {
1486                 return array_slice( debug_backtrace(), 1 );
1487         }
1488 }
1489
1490 /**
1491  * Get a debug backtrace as a string
1492  *
1493  * @param bool|null $raw If true, the return value is plain text. If false, HTML.
1494  *   Defaults to $wgCommandLineMode if unset.
1495  * @return string
1496  * @since 1.25 Supports $raw parameter.
1497  */
1498 function wfBacktrace( $raw = null ) {
1499         global $wgCommandLineMode;
1500
1501         if ( $raw === null ) {
1502                 $raw = $wgCommandLineMode;
1503         }
1504
1505         if ( $raw ) {
1506                 $frameFormat = "%s line %s calls %s()\n";
1507                 $traceFormat = "%s";
1508         } else {
1509                 $frameFormat = "<li>%s line %s calls %s()</li>\n";
1510                 $traceFormat = "<ul>\n%s</ul>\n";
1511         }
1512
1513         $frames = array_map( function ( $frame ) use ( $frameFormat ) {
1514                 $file = !empty( $frame['file'] ) ? basename( $frame['file'] ) : '-';
1515                 $line = isset( $frame['line'] ) ? $frame['line'] : '-';
1516                 $call = $frame['function'];
1517                 if ( !empty( $frame['class'] ) ) {
1518                         $call = $frame['class'] . $frame['type'] . $call;
1519                 }
1520                 return sprintf( $frameFormat, $file, $line, $call );
1521         }, wfDebugBacktrace() );
1522
1523         return sprintf( $traceFormat, implode( '', $frames ) );
1524 }
1525
1526 /**
1527  * Get the name of the function which called this function
1528  * wfGetCaller( 1 ) is the function with the wfGetCaller() call (ie. __FUNCTION__)
1529  * wfGetCaller( 2 ) [default] is the caller of the function running wfGetCaller()
1530  * wfGetCaller( 3 ) is the parent of that.
1531  *
1532  * @param int $level
1533  * @return string
1534  */
1535 function wfGetCaller( $level = 2 ) {
1536         $backtrace = wfDebugBacktrace( $level + 1 );
1537         if ( isset( $backtrace[$level] ) ) {
1538                 return wfFormatStackFrame( $backtrace[$level] );
1539         } else {
1540                 return 'unknown';
1541         }
1542 }
1543
1544 /**
1545  * Return a string consisting of callers in the stack. Useful sometimes
1546  * for profiling specific points.
1547  *
1548  * @param int $limit The maximum depth of the stack frame to return, or false for the entire stack.
1549  * @return string
1550  */
1551 function wfGetAllCallers( $limit = 3 ) {
1552         $trace = array_reverse( wfDebugBacktrace() );
1553         if ( !$limit || $limit > count( $trace ) - 1 ) {
1554                 $limit = count( $trace ) - 1;
1555         }
1556         $trace = array_slice( $trace, -$limit - 1, $limit );
1557         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1558 }
1559
1560 /**
1561  * Return a string representation of frame
1562  *
1563  * @param array $frame
1564  * @return string
1565  */
1566 function wfFormatStackFrame( $frame ) {
1567         if ( !isset( $frame['function'] ) ) {
1568                 return 'NO_FUNCTION_GIVEN';
1569         }
1570         return isset( $frame['class'] ) && isset( $frame['type'] ) ?
1571                 $frame['class'] . $frame['type'] . $frame['function'] :
1572                 $frame['function'];
1573 }
1574
1575 /* Some generic result counters, pulled out of SearchEngine */
1576
1577 /**
1578  * @todo document
1579  *
1580  * @param int $offset
1581  * @param int $limit
1582  * @return string
1583  */
1584 function wfShowingResults( $offset, $limit ) {
1585         return wfMessage( 'showingresults' )->numParams( $limit, $offset + 1 )->parse();
1586 }
1587
1588 /**
1589  * Whether the client accept gzip encoding
1590  *
1591  * Uses the Accept-Encoding header to check if the client supports gzip encoding.
1592  * Use this when considering to send a gzip-encoded response to the client.
1593  *
1594  * @param bool $force Forces another check even if we already have a cached result.
1595  * @return bool
1596  */
1597 function wfClientAcceptsGzip( $force = false ) {
1598         static $result = null;
1599         if ( $result === null || $force ) {
1600                 $result = false;
1601                 if ( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1602                         # @todo FIXME: We may want to blacklist some broken browsers
1603                         $m = [];
1604                         if ( preg_match(
1605                                         '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1606                                         $_SERVER['HTTP_ACCEPT_ENCODING'],
1607                                         $m
1608                                 )
1609                         ) {
1610                                 if ( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1611                                         $result = false;
1612                                         return $result;
1613                                 }
1614                                 wfDebug( "wfClientAcceptsGzip: client accepts gzip.\n" );
1615                                 $result = true;
1616                         }
1617                 }
1618         }
1619         return $result;
1620 }
1621
1622 /**
1623  * Escapes the given text so that it may be output using addWikiText()
1624  * without any linking, formatting, etc. making its way through. This
1625  * is achieved by substituting certain characters with HTML entities.
1626  * As required by the callers, "<nowiki>" is not used.
1627  *
1628  * @param string $text Text to be escaped
1629  * @return string
1630  */
1631 function wfEscapeWikiText( $text ) {
1632         global $wgEnableMagicLinks;
1633         static $repl = null, $repl2 = null;
1634         if ( $repl === null || defined( 'MW_PARSER_TEST' ) || defined( 'MW_PHPUNIT_TEST' ) ) {
1635                 // Tests depend upon being able to change $wgEnableMagicLinks, so don't cache
1636                 // in those situations
1637                 $repl = [
1638                         '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
1639                         '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
1640                         '{' => '&#123;', '|' => '&#124;', '}' => '&#125;', ';' => '&#59;',
1641                         "\n#" => "\n&#35;", "\r#" => "\r&#35;",
1642                         "\n*" => "\n&#42;", "\r*" => "\r&#42;",
1643                         "\n:" => "\n&#58;", "\r:" => "\r&#58;",
1644                         "\n " => "\n&#32;", "\r " => "\r&#32;",
1645                         "\n\n" => "\n&#10;", "\r\n" => "&#13;\n",
1646                         "\n\r" => "\n&#13;", "\r\r" => "\r&#13;",
1647                         "\n\t" => "\n&#9;", "\r\t" => "\r&#9;", // "\n\t\n" is treated like "\n\n"
1648                         "\n----" => "\n&#45;---", "\r----" => "\r&#45;---",
1649                         '__' => '_&#95;', '://' => '&#58;//',
1650                 ];
1651
1652                 $magicLinks = array_keys( array_filter( $wgEnableMagicLinks ) );
1653                 // We have to catch everything "\s" matches in PCRE
1654                 foreach ( $magicLinks as $magic ) {
1655                         $repl["$magic "] = "$magic&#32;";
1656                         $repl["$magic\t"] = "$magic&#9;";
1657                         $repl["$magic\r"] = "$magic&#13;";
1658                         $repl["$magic\n"] = "$magic&#10;";
1659                         $repl["$magic\f"] = "$magic&#12;";
1660                 }
1661
1662                 // And handle protocols that don't use "://"
1663                 global $wgUrlProtocols;
1664                 $repl2 = [];
1665                 foreach ( $wgUrlProtocols as $prot ) {
1666                         if ( substr( $prot, -1 ) === ':' ) {
1667                                 $repl2[] = preg_quote( substr( $prot, 0, -1 ), '/' );
1668                         }
1669                 }
1670                 $repl2 = $repl2 ? '/\b(' . implode( '|', $repl2 ) . '):/i' : '/^(?!)/';
1671         }
1672         $text = substr( strtr( "\n$text", $repl ), 1 );
1673         $text = preg_replace( $repl2, '$1&#58;', $text );
1674         return $text;
1675 }
1676
1677 /**
1678  * Sets dest to source and returns the original value of dest
1679  * If source is NULL, it just returns the value, it doesn't set the variable
1680  * If force is true, it will set the value even if source is NULL
1681  *
1682  * @param mixed &$dest
1683  * @param mixed $source
1684  * @param bool $force
1685  * @return mixed
1686  */
1687 function wfSetVar( &$dest, $source, $force = false ) {
1688         $temp = $dest;
1689         if ( !is_null( $source ) || $force ) {
1690                 $dest = $source;
1691         }
1692         return $temp;
1693 }
1694
1695 /**
1696  * As for wfSetVar except setting a bit
1697  *
1698  * @param int &$dest
1699  * @param int $bit
1700  * @param bool $state
1701  *
1702  * @return bool
1703  */
1704 function wfSetBit( &$dest, $bit, $state = true ) {
1705         $temp = (bool)( $dest & $bit );
1706         if ( !is_null( $state ) ) {
1707                 if ( $state ) {
1708                         $dest |= $bit;
1709                 } else {
1710                         $dest &= ~$bit;
1711                 }
1712         }
1713         return $temp;
1714 }
1715
1716 /**
1717  * A wrapper around the PHP function var_export().
1718  * Either print it or add it to the regular output ($wgOut).
1719  *
1720  * @param mixed $var A PHP variable to dump.
1721  */
1722 function wfVarDump( $var ) {
1723         global $wgOut;
1724         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
1725         if ( headers_sent() || !isset( $wgOut ) || !is_object( $wgOut ) ) {
1726                 print $s;
1727         } else {
1728                 $wgOut->addHTML( $s );
1729         }
1730 }
1731
1732 /**
1733  * Provide a simple HTTP error.
1734  *
1735  * @param int|string $code
1736  * @param string $label
1737  * @param string $desc
1738  */
1739 function wfHttpError( $code, $label, $desc ) {
1740         global $wgOut;
1741         HttpStatus::header( $code );
1742         if ( $wgOut ) {
1743                 $wgOut->disable();
1744                 $wgOut->sendCacheControl();
1745         }
1746
1747         MediaWiki\HeaderCallback::warnIfHeadersSent();
1748         header( 'Content-type: text/html; charset=utf-8' );
1749         print '<!DOCTYPE html>' .
1750                 '<html><head><title>' .
1751                 htmlspecialchars( $label ) .
1752                 '</title></head><body><h1>' .
1753                 htmlspecialchars( $label ) .
1754                 '</h1><p>' .
1755                 nl2br( htmlspecialchars( $desc ) ) .
1756                 "</p></body></html>\n";
1757 }
1758
1759 /**
1760  * Clear away any user-level output buffers, discarding contents.
1761  *
1762  * Suitable for 'starting afresh', for instance when streaming
1763  * relatively large amounts of data without buffering, or wanting to
1764  * output image files without ob_gzhandler's compression.
1765  *
1766  * The optional $resetGzipEncoding parameter controls suppression of
1767  * the Content-Encoding header sent by ob_gzhandler; by default it
1768  * is left. See comments for wfClearOutputBuffers() for why it would
1769  * be used.
1770  *
1771  * Note that some PHP configuration options may add output buffer
1772  * layers which cannot be removed; these are left in place.
1773  *
1774  * @param bool $resetGzipEncoding
1775  */
1776 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
1777         if ( $resetGzipEncoding ) {
1778                 // Suppress Content-Encoding and Content-Length
1779                 // headers from OutputHandler::handle.
1780                 global $wgDisableOutputCompression;
1781                 $wgDisableOutputCompression = true;
1782         }
1783         while ( $status = ob_get_status() ) {
1784                 if ( isset( $status['flags'] ) ) {
1785                         $flags = PHP_OUTPUT_HANDLER_CLEANABLE | PHP_OUTPUT_HANDLER_REMOVABLE;
1786                         $deleteable = ( $status['flags'] & $flags ) === $flags;
1787                 } elseif ( isset( $status['del'] ) ) {
1788                         $deleteable = $status['del'];
1789                 } else {
1790                         // Guess that any PHP-internal setting can't be removed.
1791                         $deleteable = $status['type'] !== 0; /* PHP_OUTPUT_HANDLER_INTERNAL */
1792                 }
1793                 if ( !$deleteable ) {
1794                         // Give up, and hope the result doesn't break
1795                         // output behavior.
1796                         break;
1797                 }
1798                 if ( $status['name'] === 'MediaWikiTestCase::wfResetOutputBuffersBarrier' ) {
1799                         // Unit testing barrier to prevent this function from breaking PHPUnit.
1800                         break;
1801                 }
1802                 if ( !ob_end_clean() ) {
1803                         // Could not remove output buffer handler; abort now
1804                         // to avoid getting in some kind of infinite loop.
1805                         break;
1806                 }
1807                 if ( $resetGzipEncoding ) {
1808                         if ( $status['name'] == 'ob_gzhandler' ) {
1809                                 // Reset the 'Content-Encoding' field set by this handler
1810                                 // so we can start fresh.
1811                                 header_remove( 'Content-Encoding' );
1812                                 break;
1813                         }
1814                 }
1815         }
1816 }
1817
1818 /**
1819  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
1820  *
1821  * Clear away output buffers, but keep the Content-Encoding header
1822  * produced by ob_gzhandler, if any.
1823  *
1824  * This should be used for HTTP 304 responses, where you need to
1825  * preserve the Content-Encoding header of the real result, but
1826  * also need to suppress the output of ob_gzhandler to keep to spec
1827  * and avoid breaking Firefox in rare cases where the headers and
1828  * body are broken over two packets.
1829  */
1830 function wfClearOutputBuffers() {
1831         wfResetOutputBuffers( false );
1832 }
1833
1834 /**
1835  * Converts an Accept-* header into an array mapping string values to quality
1836  * factors
1837  *
1838  * @param string $accept
1839  * @param string $def Default
1840  * @return float[] Associative array of string => float pairs
1841  */
1842 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
1843         # No arg means accept anything (per HTTP spec)
1844         if ( !$accept ) {
1845                 return [ $def => 1.0 ];
1846         }
1847
1848         $prefs = [];
1849
1850         $parts = explode( ',', $accept );
1851
1852         foreach ( $parts as $part ) {
1853                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
1854                 $values = explode( ';', trim( $part ) );
1855                 $match = [];
1856                 if ( count( $values ) == 1 ) {
1857                         $prefs[$values[0]] = 1.0;
1858                 } elseif ( preg_match( '/q\s*=\s*(\d*\.\d+)/', $values[1], $match ) ) {
1859                         $prefs[$values[0]] = floatval( $match[1] );
1860                 }
1861         }
1862
1863         return $prefs;
1864 }
1865
1866 /**
1867  * Checks if a given MIME type matches any of the keys in the given
1868  * array. Basic wildcards are accepted in the array keys.
1869  *
1870  * Returns the matching MIME type (or wildcard) if a match, otherwise
1871  * NULL if no match.
1872  *
1873  * @param string $type
1874  * @param array $avail
1875  * @return string
1876  * @private
1877  */
1878 function mimeTypeMatch( $type, $avail ) {
1879         if ( array_key_exists( $type, $avail ) ) {
1880                 return $type;
1881         } else {
1882                 $mainType = explode( '/', $type )[0];
1883                 if ( array_key_exists( "$mainType/*", $avail ) ) {
1884                         return "$mainType/*";
1885                 } elseif ( array_key_exists( '*/*', $avail ) ) {
1886                         return '*/*';
1887                 } else {
1888                         return null;
1889                 }
1890         }
1891 }
1892
1893 /**
1894  * Returns the 'best' match between a client's requested internet media types
1895  * and the server's list of available types. Each list should be an associative
1896  * array of type to preference (preference is a float between 0.0 and 1.0).
1897  * Wildcards in the types are acceptable.
1898  *
1899  * @param array $cprefs Client's acceptable type list
1900  * @param array $sprefs Server's offered types
1901  * @return string
1902  *
1903  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
1904  * XXX: generalize to negotiate other stuff
1905  */
1906 function wfNegotiateType( $cprefs, $sprefs ) {
1907         $combine = [];
1908
1909         foreach ( array_keys( $sprefs ) as $type ) {
1910                 $subType = explode( '/', $type )[1];
1911                 if ( $subType != '*' ) {
1912                         $ckey = mimeTypeMatch( $type, $cprefs );
1913                         if ( $ckey ) {
1914                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
1915                         }
1916                 }
1917         }
1918
1919         foreach ( array_keys( $cprefs ) as $type ) {
1920                 $subType = explode( '/', $type )[1];
1921                 if ( $subType != '*' && !array_key_exists( $type, $sprefs ) ) {
1922                         $skey = mimeTypeMatch( $type, $sprefs );
1923                         if ( $skey ) {
1924                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
1925                         }
1926                 }
1927         }
1928
1929         $bestq = 0;
1930         $besttype = null;
1931
1932         foreach ( array_keys( $combine ) as $type ) {
1933                 if ( $combine[$type] > $bestq ) {
1934                         $besttype = $type;
1935                         $bestq = $combine[$type];
1936                 }
1937         }
1938
1939         return $besttype;
1940 }
1941
1942 /**
1943  * Reference-counted warning suppression
1944  *
1945  * @deprecated since 1.26, use Wikimedia\suppressWarnings() directly
1946  * @param bool $end
1947  */
1948 function wfSuppressWarnings( $end = false ) {
1949         Wikimedia\suppressWarnings( $end );
1950 }
1951
1952 /**
1953  * @deprecated since 1.26, use Wikimedia\restoreWarnings() directly
1954  * Restore error level to previous value
1955  */
1956 function wfRestoreWarnings() {
1957         Wikimedia\restoreWarnings();
1958 }
1959
1960 /**
1961  * Get a timestamp string in one of various formats
1962  *
1963  * @param mixed $outputtype A timestamp in one of the supported formats, the
1964  *   function will autodetect which format is supplied and act accordingly.
1965  * @param mixed $ts Optional timestamp to convert, default 0 for the current time
1966  * @return string|bool String / false The same date in the format specified in $outputtype or false
1967  */
1968 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
1969         $ret = MWTimestamp::convert( $outputtype, $ts );
1970         if ( $ret === false ) {
1971                 wfDebug( "wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n" );
1972         }
1973         return $ret;
1974 }
1975
1976 /**
1977  * Return a formatted timestamp, or null if input is null.
1978  * For dealing with nullable timestamp columns in the database.
1979  *
1980  * @param int $outputtype
1981  * @param string $ts
1982  * @return string
1983  */
1984 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
1985         if ( is_null( $ts ) ) {
1986                 return null;
1987         } else {
1988                 return wfTimestamp( $outputtype, $ts );
1989         }
1990 }
1991
1992 /**
1993  * Convenience function; returns MediaWiki timestamp for the present time.
1994  *
1995  * @return string
1996  */
1997 function wfTimestampNow() {
1998         # return NOW
1999         return MWTimestamp::now( TS_MW );
2000 }
2001
2002 /**
2003  * Check if the operating system is Windows
2004  *
2005  * @return bool True if it's Windows, false otherwise.
2006  */
2007 function wfIsWindows() {
2008         static $isWindows = null;
2009         if ( $isWindows === null ) {
2010                 $isWindows = strtoupper( substr( PHP_OS, 0, 3 ) ) === 'WIN';
2011         }
2012         return $isWindows;
2013 }
2014
2015 /**
2016  * Check if we are running under HHVM
2017  *
2018  * @return bool
2019  */
2020 function wfIsHHVM() {
2021         return defined( 'HHVM_VERSION' );
2022 }
2023
2024 /**
2025  * Check if we are running from the commandline
2026  *
2027  * @since 1.31
2028  * @return bool
2029  */
2030 function wfIsCLI() {
2031         return PHP_SAPI === 'cli' || PHP_SAPI === 'phpdbg';
2032 }
2033
2034 /**
2035  * Tries to get the system directory for temporary files. First
2036  * $wgTmpDirectory is checked, and then the TMPDIR, TMP, and TEMP
2037  * environment variables are then checked in sequence, then
2038  * sys_get_temp_dir(), then upload_tmp_dir from php.ini.
2039  *
2040  * NOTE: When possible, use instead the tmpfile() function to create
2041  * temporary files to avoid race conditions on file creation, etc.
2042  *
2043  * @return string
2044  */
2045 function wfTempDir() {
2046         global $wgTmpDirectory;
2047
2048         if ( $wgTmpDirectory !== false ) {
2049                 return $wgTmpDirectory;
2050         }
2051
2052         return TempFSFile::getUsableTempDirectory();
2053 }
2054
2055 /**
2056  * Make directory, and make all parent directories if they don't exist
2057  *
2058  * @param string $dir Full path to directory to create
2059  * @param int $mode Chmod value to use, default is $wgDirectoryMode
2060  * @param string $caller Optional caller param for debugging.
2061  * @throws MWException
2062  * @return bool
2063  */
2064 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2065         global $wgDirectoryMode;
2066
2067         if ( FileBackend::isStoragePath( $dir ) ) { // sanity
2068                 throw new MWException( __FUNCTION__ . " given storage path '$dir'." );
2069         }
2070
2071         if ( !is_null( $caller ) ) {
2072                 wfDebug( "$caller: called wfMkdirParents($dir)\n" );
2073         }
2074
2075         if ( strval( $dir ) === '' || is_dir( $dir ) ) {
2076                 return true;
2077         }
2078
2079         $dir = str_replace( [ '\\', '/' ], DIRECTORY_SEPARATOR, $dir );
2080
2081         if ( is_null( $mode ) ) {
2082                 $mode = $wgDirectoryMode;
2083         }
2084
2085         // Turn off the normal warning, we're doing our own below
2086         Wikimedia\suppressWarnings();
2087         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2088         Wikimedia\restoreWarnings();
2089
2090         if ( !$ok ) {
2091                 // directory may have been created on another request since we last checked
2092                 if ( is_dir( $dir ) ) {
2093                         return true;
2094                 }
2095
2096                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2097                 wfLogWarning( sprintf( "failed to mkdir \"%s\" mode 0%o", $dir, $mode ) );
2098         }
2099         return $ok;
2100 }
2101
2102 /**
2103  * Remove a directory and all its content.
2104  * Does not hide error.
2105  * @param string $dir
2106  */
2107 function wfRecursiveRemoveDir( $dir ) {
2108         wfDebug( __FUNCTION__ . "( $dir )\n" );
2109         // taken from https://secure.php.net/manual/en/function.rmdir.php#98622
2110         if ( is_dir( $dir ) ) {
2111                 $objects = scandir( $dir );
2112                 foreach ( $objects as $object ) {
2113                         if ( $object != "." && $object != ".." ) {
2114                                 if ( filetype( $dir . '/' . $object ) == "dir" ) {
2115                                         wfRecursiveRemoveDir( $dir . '/' . $object );
2116                                 } else {
2117                                         unlink( $dir . '/' . $object );
2118                                 }
2119                         }
2120                 }
2121                 reset( $objects );
2122                 rmdir( $dir );
2123         }
2124 }
2125
2126 /**
2127  * @param int $nr The number to format
2128  * @param int $acc The number of digits after the decimal point, default 2
2129  * @param bool $round Whether or not to round the value, default true
2130  * @return string
2131  */
2132 function wfPercent( $nr, $acc = 2, $round = true ) {
2133         $ret = sprintf( "%.${acc}f", $nr );
2134         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2135 }
2136
2137 /**
2138  * Safety wrapper around ini_get() for boolean settings.
2139  * The values returned from ini_get() are pre-normalized for settings
2140  * set via php.ini or php_flag/php_admin_flag... but *not*
2141  * for those set via php_value/php_admin_value.
2142  *
2143  * It's fairly common for people to use php_value instead of php_flag,
2144  * which can leave you with an 'off' setting giving a false positive
2145  * for code that just takes the ini_get() return value as a boolean.
2146  *
2147  * To make things extra interesting, setting via php_value accepts
2148  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2149  * Unrecognized values go false... again opposite PHP's own coercion
2150  * from string to bool.
2151  *
2152  * Luckily, 'properly' set settings will always come back as '0' or '1',
2153  * so we only have to worry about them and the 'improper' settings.
2154  *
2155  * I frickin' hate PHP... :P
2156  *
2157  * @param string $setting
2158  * @return bool
2159  */
2160 function wfIniGetBool( $setting ) {
2161         return wfStringToBool( ini_get( $setting ) );
2162 }
2163
2164 /**
2165  * Convert string value to boolean, when the following are interpreted as true:
2166  * - on
2167  * - true
2168  * - yes
2169  * - Any number, except 0
2170  * All other strings are interpreted as false.
2171  *
2172  * @param string $val
2173  * @return bool
2174  * @since 1.31
2175  */
2176 function wfStringToBool( $val ) {
2177         $val = strtolower( $val );
2178         // 'on' and 'true' can't have whitespace around them, but '1' can.
2179         return $val == 'on'
2180                 || $val == 'true'
2181                 || $val == 'yes'
2182                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2183 }
2184
2185 /**
2186  * Version of escapeshellarg() that works better on Windows.
2187  *
2188  * Originally, this fixed the incorrect use of single quotes on Windows
2189  * (https://bugs.php.net/bug.php?id=26285) and the locale problems on Linux in
2190  * PHP 5.2.6+ (bug backported to earlier distro releases of PHP).
2191  *
2192  * @param string $args,... strings to escape and glue together,
2193  *  or a single array of strings parameter
2194  * @return string
2195  * @deprecated since 1.30 use MediaWiki\Shell::escape()
2196  */
2197 function wfEscapeShellArg( /*...*/ ) {
2198         $args = func_get_args();
2199
2200         return call_user_func_array( Shell::class . '::escape', $args );
2201 }
2202
2203 /**
2204  * Check if wfShellExec() is effectively disabled via php.ini config
2205  *
2206  * @return bool|string False or 'disabled'
2207  * @since 1.22
2208  * @deprecated since 1.30 use MediaWiki\Shell::isDisabled()
2209  */
2210 function wfShellExecDisabled() {
2211         wfDeprecated( __FUNCTION__, '1.30' );
2212         return Shell::isDisabled() ? 'disabled' : false;
2213 }
2214
2215 /**
2216  * Execute a shell command, with time and memory limits mirrored from the PHP
2217  * configuration if supported.
2218  *
2219  * @param string|string[] $cmd If string, a properly shell-escaped command line,
2220  *   or an array of unescaped arguments, in which case each value will be escaped
2221  *   Example:   [ 'convert', '-font', 'font name' ] would produce "'convert' '-font' 'font name'"
2222  * @param null|mixed &$retval Optional, will receive the program's exit code.
2223  *   (non-zero is usually failure). If there is an error from
2224  *   read, select, or proc_open(), this will be set to -1.
2225  * @param array $environ Optional environment variables which should be
2226  *   added to the executed command environment.
2227  * @param array $limits Optional array with limits(filesize, memory, time, walltime)
2228  *   this overwrites the global wgMaxShell* limits.
2229  * @param array $options Array of options:
2230  *   - duplicateStderr: Set this to true to duplicate stderr to stdout,
2231  *     including errors from limit.sh
2232  *   - profileMethod: By default this function will profile based on the calling
2233  *     method. Set this to a string for an alternative method to profile from
2234  *
2235  * @return string Collected stdout as a string
2236  * @deprecated since 1.30 use class MediaWiki\Shell\Shell
2237  */
2238 function wfShellExec( $cmd, &$retval = null, $environ = [],
2239         $limits = [], $options = []
2240 ) {
2241         if ( Shell::isDisabled() ) {
2242                 $retval = 1;
2243                 // Backwards compatibility be upon us...
2244                 return 'Unable to run external programs, proc_open() is disabled.';
2245         }
2246
2247         if ( is_array( $cmd ) ) {
2248                 $cmd = Shell::escape( $cmd );
2249         }
2250
2251         $includeStderr = isset( $options['duplicateStderr'] ) && $options['duplicateStderr'];
2252         $profileMethod = isset( $options['profileMethod'] ) ? $options['profileMethod'] : wfGetCaller();
2253
2254         try {
2255                 $result = Shell::command( [] )
2256                         ->unsafeParams( (array)$cmd )
2257                         ->environment( $environ )
2258                         ->limits( $limits )
2259                         ->includeStderr( $includeStderr )
2260                         ->profileMethod( $profileMethod )
2261                         // For b/c
2262                         ->restrict( Shell::RESTRICT_NONE )
2263                         ->execute();
2264         } catch ( ProcOpenError $ex ) {
2265                 $retval = -1;
2266                 return '';
2267         }
2268
2269         $retval = $result->getExitCode();
2270
2271         return $result->getStdout();
2272 }
2273
2274 /**
2275  * Execute a shell command, returning both stdout and stderr. Convenience
2276  * function, as all the arguments to wfShellExec can become unwieldy.
2277  *
2278  * @note This also includes errors from limit.sh, e.g. if $wgMaxShellFileSize is exceeded.
2279  * @param string|string[] $cmd If string, a properly shell-escaped command line,
2280  *   or an array of unescaped arguments, in which case each value will be escaped
2281  *   Example:   [ 'convert', '-font', 'font name' ] would produce "'convert' '-font' 'font name'"
2282  * @param null|mixed &$retval Optional, will receive the program's exit code.
2283  *   (non-zero is usually failure)
2284  * @param array $environ Optional environment variables which should be
2285  *   added to the executed command environment.
2286  * @param array $limits Optional array with limits(filesize, memory, time, walltime)
2287  *   this overwrites the global wgMaxShell* limits.
2288  * @return string Collected stdout and stderr as a string
2289  * @deprecated since 1.30 use class MediaWiki\Shell\Shell
2290  */
2291 function wfShellExecWithStderr( $cmd, &$retval = null, $environ = [], $limits = [] ) {
2292         return wfShellExec( $cmd, $retval, $environ, $limits,
2293                 [ 'duplicateStderr' => true, 'profileMethod' => wfGetCaller() ] );
2294 }
2295
2296 /**
2297  * Formerly set the locale for locale-sensitive operations
2298  *
2299  * This is now done in Setup.php.
2300  *
2301  * @deprecated since 1.30, no longer needed
2302  * @see $wgShellLocale
2303  */
2304 function wfInitShellLocale() {
2305         wfDeprecated( __FUNCTION__, '1.30' );
2306 }
2307
2308 /**
2309  * Generate a shell-escaped command line string to run a MediaWiki cli script.
2310  * Note that $parameters should be a flat array and an option with an argument
2311  * should consist of two consecutive items in the array (do not use "--option value").
2312  *
2313  * @deprecated since 1.31, use Shell::makeScriptCommand()
2314  *
2315  * @param string $script MediaWiki cli script path
2316  * @param array $parameters Arguments and options to the script
2317  * @param array $options Associative array of options:
2318  *     'php': The path to the php executable
2319  *     'wrapper': Path to a PHP wrapper to handle the maintenance script
2320  * @return string
2321  */
2322 function wfShellWikiCmd( $script, array $parameters = [], array $options = [] ) {
2323         global $wgPhpCli;
2324         // Give site config file a chance to run the script in a wrapper.
2325         // The caller may likely want to call wfBasename() on $script.
2326         Hooks::run( 'wfShellWikiCmd', [ &$script, &$parameters, &$options ] );
2327         $cmd = isset( $options['php'] ) ? [ $options['php'] ] : [ $wgPhpCli ];
2328         if ( isset( $options['wrapper'] ) ) {
2329                 $cmd[] = $options['wrapper'];
2330         }
2331         $cmd[] = $script;
2332         // Escape each parameter for shell
2333         return Shell::escape( array_merge( $cmd, $parameters ) );
2334 }
2335
2336 /**
2337  * wfMerge attempts to merge differences between three texts.
2338  * Returns true for a clean merge and false for failure or a conflict.
2339  *
2340  * @param string $old
2341  * @param string $mine
2342  * @param string $yours
2343  * @param string &$result
2344  * @param string &$mergeAttemptResult
2345  * @return bool
2346  */
2347 function wfMerge( $old, $mine, $yours, &$result, &$mergeAttemptResult = null ) {
2348         global $wgDiff3;
2349
2350         # This check may also protect against code injection in
2351         # case of broken installations.
2352         Wikimedia\suppressWarnings();
2353         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
2354         Wikimedia\restoreWarnings();
2355
2356         if ( !$haveDiff3 ) {
2357                 wfDebug( "diff3 not found\n" );
2358                 return false;
2359         }
2360
2361         # Make temporary files
2362         $td = wfTempDir();
2363         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
2364         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
2365         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
2366
2367         # NOTE: diff3 issues a warning to stderr if any of the files does not end with
2368         #       a newline character. To avoid this, we normalize the trailing whitespace before
2369         #       creating the diff.
2370
2371         fwrite( $oldtextFile, rtrim( $old ) . "\n" );
2372         fclose( $oldtextFile );
2373         fwrite( $mytextFile, rtrim( $mine ) . "\n" );
2374         fclose( $mytextFile );
2375         fwrite( $yourtextFile, rtrim( $yours ) . "\n" );
2376         fclose( $yourtextFile );
2377
2378         # Check for a conflict
2379         $cmd = Shell::escape( $wgDiff3, '-a', '--overlap-only', $mytextName,
2380                 $oldtextName, $yourtextName );
2381         $handle = popen( $cmd, 'r' );
2382
2383         $mergeAttemptResult = '';
2384         do {
2385                 $data = fread( $handle, 8192 );
2386                 if ( strlen( $data ) == 0 ) {
2387                         break;
2388                 }
2389                 $mergeAttemptResult .= $data;
2390         } while ( true );
2391         pclose( $handle );
2392
2393         $conflict = $mergeAttemptResult !== '';
2394
2395         # Merge differences
2396         $cmd = Shell::escape( $wgDiff3, '-a', '-e', '--merge', $mytextName,
2397                 $oldtextName, $yourtextName );
2398         $handle = popen( $cmd, 'r' );
2399         $result = '';
2400         do {
2401                 $data = fread( $handle, 8192 );
2402                 if ( strlen( $data ) == 0 ) {
2403                         break;
2404                 }
2405                 $result .= $data;
2406         } while ( true );
2407         pclose( $handle );
2408         unlink( $mytextName );
2409         unlink( $oldtextName );
2410         unlink( $yourtextName );
2411
2412         if ( $result === '' && $old !== '' && !$conflict ) {
2413                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
2414                 $conflict = true;
2415         }
2416         return !$conflict;
2417 }
2418
2419 /**
2420  * Returns unified plain-text diff of two texts.
2421  * "Useful" for machine processing of diffs.
2422  *
2423  * @deprecated since 1.25, use DiffEngine/UnifiedDiffFormatter directly
2424  *
2425  * @param string $before The text before the changes.
2426  * @param string $after The text after the changes.
2427  * @param string $params Command-line options for the diff command.
2428  * @return string Unified diff of $before and $after
2429  */
2430 function wfDiff( $before, $after, $params = '-u' ) {
2431         if ( $before == $after ) {
2432                 return '';
2433         }
2434
2435         global $wgDiff;
2436         Wikimedia\suppressWarnings();
2437         $haveDiff = $wgDiff && file_exists( $wgDiff );
2438         Wikimedia\restoreWarnings();
2439
2440         # This check may also protect against code injection in
2441         # case of broken installations.
2442         if ( !$haveDiff ) {
2443                 wfDebug( "diff executable not found\n" );
2444                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
2445                 $format = new UnifiedDiffFormatter();
2446                 return $format->format( $diffs );
2447         }
2448
2449         # Make temporary files
2450         $td = wfTempDir();
2451         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
2452         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
2453
2454         fwrite( $oldtextFile, $before );
2455         fclose( $oldtextFile );
2456         fwrite( $newtextFile, $after );
2457         fclose( $newtextFile );
2458
2459         // Get the diff of the two files
2460         $cmd = "$wgDiff " . $params . ' ' . Shell::escape( $oldtextName, $newtextName );
2461
2462         $h = popen( $cmd, 'r' );
2463         if ( !$h ) {
2464                 unlink( $oldtextName );
2465                 unlink( $newtextName );
2466                 throw new Exception( __METHOD__ . '(): popen() failed' );
2467         }
2468
2469         $diff = '';
2470
2471         do {
2472                 $data = fread( $h, 8192 );
2473                 if ( strlen( $data ) == 0 ) {
2474                         break;
2475                 }
2476                 $diff .= $data;
2477         } while ( true );
2478
2479         // Clean up
2480         pclose( $h );
2481         unlink( $oldtextName );
2482         unlink( $newtextName );
2483
2484         // Kill the --- and +++ lines. They're not useful.
2485         $diff_lines = explode( "\n", $diff );
2486         if ( isset( $diff_lines[0] ) && strpos( $diff_lines[0], '---' ) === 0 ) {
2487                 unset( $diff_lines[0] );
2488         }
2489         if ( isset( $diff_lines[1] ) && strpos( $diff_lines[1], '+++' ) === 0 ) {
2490                 unset( $diff_lines[1] );
2491         }
2492
2493         $diff = implode( "\n", $diff_lines );
2494
2495         return $diff;
2496 }
2497
2498 /**
2499  * This function works like "use VERSION" in Perl, the program will die with a
2500  * backtrace if the current version of PHP is less than the version provided
2501  *
2502  * This is useful for extensions which due to their nature are not kept in sync
2503  * with releases, and might depend on other versions of PHP than the main code
2504  *
2505  * Note: PHP might die due to parsing errors in some cases before it ever
2506  *       manages to call this function, such is life
2507  *
2508  * @see perldoc -f use
2509  *
2510  * @param string|int|float $req_ver The version to check, can be a string, an integer, or a float
2511  *
2512  * @deprecated since 1.30
2513  *
2514  * @throws MWException
2515  */
2516 function wfUsePHP( $req_ver ) {
2517         wfDeprecated( __FUNCTION__, '1.30' );
2518         $php_ver = PHP_VERSION;
2519
2520         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
2521                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
2522         }
2523 }
2524
2525 /**
2526  * This function works like "use VERSION" in Perl except it checks the version
2527  * of MediaWiki, the program will die with a backtrace if the current version
2528  * of MediaWiki is less than the version provided.
2529  *
2530  * This is useful for extensions which due to their nature are not kept in sync
2531  * with releases
2532  *
2533  * Note: Due to the behavior of PHP's version_compare() which is used in this
2534  * function, if you want to allow the 'wmf' development versions add a 'c' (or
2535  * any single letter other than 'a', 'b' or 'p') as a post-fix to your
2536  * targeted version number. For example if you wanted to allow any variation
2537  * of 1.22 use `wfUseMW( '1.22c' )`. Using an 'a' or 'b' instead of 'c' will
2538  * not result in the same comparison due to the internal logic of
2539  * version_compare().
2540  *
2541  * @see perldoc -f use
2542  *
2543  * @deprecated since 1.26, use the "requires" property of extension.json
2544  * @param string|int|float $req_ver The version to check, can be a string, an integer, or a float
2545  * @throws MWException
2546  */
2547 function wfUseMW( $req_ver ) {
2548         global $wgVersion;
2549
2550         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
2551                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
2552         }
2553 }
2554
2555 /**
2556  * Return the final portion of a pathname.
2557  * Reimplemented because PHP5's "basename()" is buggy with multibyte text.
2558  * https://bugs.php.net/bug.php?id=33898
2559  *
2560  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
2561  * We'll consider it so always, as we don't want '\s' in our Unix paths either.
2562  *
2563  * @param string $path
2564  * @param string $suffix String to remove if present
2565  * @return string
2566  */
2567 function wfBaseName( $path, $suffix = '' ) {
2568         if ( $suffix == '' ) {
2569                 $encSuffix = '';
2570         } else {
2571                 $encSuffix = '(?:' . preg_quote( $suffix, '#' ) . ')?';
2572         }
2573
2574         $matches = [];
2575         if ( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2576                 return $matches[1];
2577         } else {
2578                 return '';
2579         }
2580 }
2581
2582 /**
2583  * Generate a relative path name to the given file.
2584  * May explode on non-matching case-insensitive paths,
2585  * funky symlinks, etc.
2586  *
2587  * @param string $path Absolute destination path including target filename
2588  * @param string $from Absolute source path, directory only
2589  * @return string
2590  */
2591 function wfRelativePath( $path, $from ) {
2592         // Normalize mixed input on Windows...
2593         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2594         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2595
2596         // Trim trailing slashes -- fix for drive root
2597         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2598         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2599
2600         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2601         $against = explode( DIRECTORY_SEPARATOR, $from );
2602
2603         if ( $pieces[0] !== $against[0] ) {
2604                 // Non-matching Windows drive letters?
2605                 // Return a full path.
2606                 return $path;
2607         }
2608
2609         // Trim off common prefix
2610         while ( count( $pieces ) && count( $against )
2611                 && $pieces[0] == $against[0] ) {
2612                 array_shift( $pieces );
2613                 array_shift( $against );
2614         }
2615
2616         // relative dots to bump us to the parent
2617         while ( count( $against ) ) {
2618                 array_unshift( $pieces, '..' );
2619                 array_shift( $against );
2620         }
2621
2622         array_push( $pieces, wfBaseName( $path ) );
2623
2624         return implode( DIRECTORY_SEPARATOR, $pieces );
2625 }
2626
2627 /**
2628  * Reset the session id
2629  *
2630  * @deprecated since 1.27, use MediaWiki\Session\SessionManager instead
2631  * @since 1.22
2632  */
2633 function wfResetSessionID() {
2634         wfDeprecated( __FUNCTION__, '1.27' );
2635         $session = SessionManager::getGlobalSession();
2636         $delay = $session->delaySave();
2637
2638         $session->resetId();
2639
2640         // Make sure a session is started, since that's what the old
2641         // wfResetSessionID() did.
2642         if ( session_id() !== $session->getId() ) {
2643                 wfSetupSession( $session->getId() );
2644         }
2645
2646         ScopedCallback::consume( $delay );
2647 }
2648
2649 /**
2650  * Initialise php session
2651  *
2652  * @deprecated since 1.27, use MediaWiki\Session\SessionManager instead.
2653  *  Generally, "using" SessionManager will be calling ->getSessionById() or
2654  *  ::getGlobalSession() (depending on whether you were passing $sessionId
2655  *  here), then calling $session->persist().
2656  * @param bool|string $sessionId
2657  */
2658 function wfSetupSession( $sessionId = false ) {
2659         wfDeprecated( __FUNCTION__, '1.27' );
2660
2661         if ( $sessionId ) {
2662                 session_id( $sessionId );
2663         }
2664
2665         $session = SessionManager::getGlobalSession();
2666         $session->persist();
2667
2668         if ( session_id() !== $session->getId() ) {
2669                 session_id( $session->getId() );
2670         }
2671         Wikimedia\quietCall( 'session_start' );
2672 }
2673
2674 /**
2675  * Get an object from the precompiled serialized directory
2676  *
2677  * @param string $name
2678  * @return mixed The variable on success, false on failure
2679  */
2680 function wfGetPrecompiledData( $name ) {
2681         global $IP;
2682
2683         $file = "$IP/serialized/$name";
2684         if ( file_exists( $file ) ) {
2685                 $blob = file_get_contents( $file );
2686                 if ( $blob ) {
2687                         return unserialize( $blob );
2688                 }
2689         }
2690         return false;
2691 }
2692
2693 /**
2694  * Make a cache key for the local wiki.
2695  *
2696  * @deprecated since 1.30 Call makeKey on a BagOStuff instance
2697  * @param string $args,...
2698  * @return string
2699  */
2700 function wfMemcKey( /*...*/ ) {
2701         return call_user_func_array(
2702                 [ ObjectCache::getLocalClusterInstance(), 'makeKey' ],
2703                 func_get_args()
2704         );
2705 }
2706
2707 /**
2708  * Make a cache key for a foreign DB.
2709  *
2710  * Must match what wfMemcKey() would produce in context of the foreign wiki.
2711  *
2712  * @param string $db
2713  * @param string $prefix
2714  * @param string $args,...
2715  * @return string
2716  */
2717 function wfForeignMemcKey( $db, $prefix /*...*/ ) {
2718         $args = array_slice( func_get_args(), 2 );
2719         $keyspace = $prefix ? "$db-$prefix" : $db;
2720         return call_user_func_array(
2721                 [ ObjectCache::getLocalClusterInstance(), 'makeKeyInternal' ],
2722                 [ $keyspace, $args ]
2723         );
2724 }
2725
2726 /**
2727  * Make a cache key with database-agnostic prefix.
2728  *
2729  * Doesn't have a wiki-specific namespace. Uses a generic 'global' prefix
2730  * instead. Must have a prefix as otherwise keys that use a database name
2731  * in the first segment will clash with wfMemcKey/wfForeignMemcKey.
2732  *
2733  * @deprecated since 1.30 Call makeGlobalKey on a BagOStuff instance
2734  * @since 1.26
2735  * @param string $args,...
2736  * @return string
2737  */
2738 function wfGlobalCacheKey( /*...*/ ) {
2739         return call_user_func_array(
2740                 [ ObjectCache::getLocalClusterInstance(), 'makeGlobalKey' ],
2741                 func_get_args()
2742         );
2743 }
2744
2745 /**
2746  * Get an ASCII string identifying this wiki
2747  * This is used as a prefix in memcached keys
2748  *
2749  * @return string
2750  */
2751 function wfWikiID() {
2752         global $wgDBprefix, $wgDBname;
2753         if ( $wgDBprefix ) {
2754                 return "$wgDBname-$wgDBprefix";
2755         } else {
2756                 return $wgDBname;
2757         }
2758 }
2759
2760 /**
2761  * Split a wiki ID into DB name and table prefix
2762  *
2763  * @param string $wiki
2764  *
2765  * @return array
2766  */
2767 function wfSplitWikiID( $wiki ) {
2768         $bits = explode( '-', $wiki, 2 );
2769         if ( count( $bits ) < 2 ) {
2770                 $bits[] = '';
2771         }
2772         return $bits;
2773 }
2774
2775 /**
2776  * Get a Database object.
2777  *
2778  * @param int $db Index of the connection to get. May be DB_MASTER for the
2779  *            master (for write queries), DB_REPLICA for potentially lagged read
2780  *            queries, or an integer >= 0 for a particular server.
2781  *
2782  * @param string|string[] $groups Query groups. An array of group names that this query
2783  *                belongs to. May contain a single string if the query is only
2784  *                in one group.
2785  *
2786  * @param string|bool $wiki The wiki ID, or false for the current wiki
2787  *
2788  * Note: multiple calls to wfGetDB(DB_REPLICA) during the course of one request
2789  * will always return the same object, unless the underlying connection or load
2790  * balancer is manually destroyed.
2791  *
2792  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
2793  * updater to ensure that a proper database is being updated.
2794  *
2795  * @todo Replace calls to wfGetDB with calls to LoadBalancer::getConnection()
2796  *       on an injected instance of LoadBalancer.
2797  *
2798  * @return \Wikimedia\Rdbms\Database
2799  */
2800 function wfGetDB( $db, $groups = [], $wiki = false ) {
2801         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
2802 }
2803
2804 /**
2805  * Get a load balancer object.
2806  *
2807  * @deprecated since 1.27, use MediaWikiServices::getDBLoadBalancer()
2808  *              or MediaWikiServices::getDBLoadBalancerFactory() instead.
2809  *
2810  * @param string|bool $wiki Wiki ID, or false for the current wiki
2811  * @return \Wikimedia\Rdbms\LoadBalancer
2812  */
2813 function wfGetLB( $wiki = false ) {
2814         if ( $wiki === false ) {
2815                 return MediaWikiServices::getInstance()->getDBLoadBalancer();
2816         } else {
2817                 $factory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
2818                 return $factory->getMainLB( $wiki );
2819         }
2820 }
2821
2822 /**
2823  * Get the load balancer factory object
2824  *
2825  * @deprecated since 1.27, use MediaWikiServices::getDBLoadBalancerFactory() instead.
2826  *
2827  * @return \Wikimedia\Rdbms\LBFactory
2828  */
2829 function wfGetLBFactory() {
2830         return MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
2831 }
2832
2833 /**
2834  * Find a file.
2835  * Shortcut for RepoGroup::singleton()->findFile()
2836  *
2837  * @param string|Title $title String or Title object
2838  * @param array $options Associative array of options (see RepoGroup::findFile)
2839  * @return File|bool File, or false if the file does not exist
2840  */
2841 function wfFindFile( $title, $options = [] ) {
2842         return RepoGroup::singleton()->findFile( $title, $options );
2843 }
2844
2845 /**
2846  * Get an object referring to a locally registered file.
2847  * Returns a valid placeholder object if the file does not exist.
2848  *
2849  * @param Title|string $title
2850  * @return LocalFile|null A File, or null if passed an invalid Title
2851  */
2852 function wfLocalFile( $title ) {
2853         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
2854 }
2855
2856 /**
2857  * Should low-performance queries be disabled?
2858  *
2859  * @return bool
2860  * @codeCoverageIgnore
2861  */
2862 function wfQueriesMustScale() {
2863         global $wgMiserMode;
2864         return $wgMiserMode
2865                 || ( SiteStats::pages() > 100000
2866                 && SiteStats::edits() > 1000000
2867                 && SiteStats::users() > 10000 );
2868 }
2869
2870 /**
2871  * Get the path to a specified script file, respecting file
2872  * extensions; this is a wrapper around $wgScriptPath etc.
2873  * except for 'index' and 'load' which use $wgScript/$wgLoadScript
2874  *
2875  * @param string $script Script filename, sans extension
2876  * @return string
2877  */
2878 function wfScript( $script = 'index' ) {
2879         global $wgScriptPath, $wgScript, $wgLoadScript;
2880         if ( $script === 'index' ) {
2881                 return $wgScript;
2882         } elseif ( $script === 'load' ) {
2883                 return $wgLoadScript;
2884         } else {
2885                 return "{$wgScriptPath}/{$script}.php";
2886         }
2887 }
2888
2889 /**
2890  * Get the script URL.
2891  *
2892  * @return string Script URL
2893  */
2894 function wfGetScriptUrl() {
2895         if ( isset( $_SERVER['SCRIPT_NAME'] ) ) {
2896                 /* as it was called, minus the query string.
2897                  *
2898                  * Some sites use Apache rewrite rules to handle subdomains,
2899                  * and have PHP set up in a weird way that causes PHP_SELF
2900                  * to contain the rewritten URL instead of the one that the
2901                  * outside world sees.
2902                  *
2903                  * If in this mode, use SCRIPT_URL instead, which mod_rewrite
2904                  * provides containing the "before" URL.
2905                  */
2906                 return $_SERVER['SCRIPT_NAME'];
2907         } else {
2908                 return $_SERVER['URL'];
2909         }
2910 }
2911
2912 /**
2913  * Convenience function converts boolean values into "true"
2914  * or "false" (string) values
2915  *
2916  * @param bool $value
2917  * @return string
2918  */
2919 function wfBoolToStr( $value ) {
2920         return $value ? 'true' : 'false';
2921 }
2922
2923 /**
2924  * Get a platform-independent path to the null file, e.g. /dev/null
2925  *
2926  * @return string
2927  */
2928 function wfGetNull() {
2929         return wfIsWindows() ? 'NUL' : '/dev/null';
2930 }
2931
2932 /**
2933  * Waits for the replica DBs to catch up to the master position
2934  *
2935  * Use this when updating very large numbers of rows, as in maintenance scripts,
2936  * to avoid causing too much lag. Of course, this is a no-op if there are no replica DBs.
2937  *
2938  * By default this waits on the main DB cluster of the current wiki.
2939  * If $cluster is set to "*" it will wait on all DB clusters, including
2940  * external ones. If the lag being waiting on is caused by the code that
2941  * does this check, it makes since to use $ifWritesSince, particularly if
2942  * cluster is "*", to avoid excess overhead.
2943  *
2944  * Never call this function after a big DB write that is still in a transaction.
2945  * This only makes sense after the possible lag inducing changes were committed.
2946  *
2947  * @param float|null $ifWritesSince Only wait if writes were done since this UNIX timestamp
2948  * @param string|bool $wiki Wiki identifier accepted by wfGetLB
2949  * @param string|bool $cluster Cluster name accepted by LBFactory. Default: false.
2950  * @param int|null $timeout Max wait time. Default: 1 day (cli), ~10 seconds (web)
2951  * @return bool Success (able to connect and no timeouts reached)
2952  * @deprecated since 1.27 Use LBFactory::waitForReplication
2953  */
2954 function wfWaitForSlaves(
2955         $ifWritesSince = null, $wiki = false, $cluster = false, $timeout = null
2956 ) {
2957         if ( $timeout === null ) {
2958                 $timeout = wfIsCLI() ? 60 : 10;
2959         }
2960
2961         if ( $cluster === '*' ) {
2962                 $cluster = false;
2963                 $wiki = false;
2964         } elseif ( $wiki === false ) {
2965                 $wiki = wfWikiID();
2966         }
2967
2968         try {
2969                 $lbFactory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
2970                 $lbFactory->waitForReplication( [
2971                         'wiki' => $wiki,
2972                         'cluster' => $cluster,
2973                         'timeout' => $timeout,
2974                         // B/C: first argument used to be "max seconds of lag"; ignore such values
2975                         'ifWritesSince' => ( $ifWritesSince > 1e9 ) ? $ifWritesSince : null
2976                 ] );
2977         } catch ( DBReplicationWaitError $e ) {
2978                 return false;
2979         }
2980
2981         return true;
2982 }
2983
2984 /**
2985  * Count down from $seconds to zero on the terminal, with a one-second pause
2986  * between showing each number. For use in command-line scripts.
2987  *
2988  * @deprecated since 1.31, use Maintenance::countDown()
2989  *
2990  * @codeCoverageIgnore
2991  * @param int $seconds
2992  */
2993 function wfCountDown( $seconds ) {
2994         for ( $i = $seconds; $i >= 0; $i-- ) {
2995                 if ( $i != $seconds ) {
2996                         echo str_repeat( "\x08", strlen( $i + 1 ) );
2997                 }
2998                 echo $i;
2999                 flush();
3000                 if ( $i ) {
3001                         sleep( 1 );
3002                 }
3003         }
3004         echo "\n";
3005 }
3006
3007 /**
3008  * Replace all invalid characters with '-'.
3009  * Additional characters can be defined in $wgIllegalFileChars (see T22489).
3010  * By default, $wgIllegalFileChars includes ':', '/', '\'.
3011  *
3012  * @param string $name Filename to process
3013  * @return string
3014  */
3015 function wfStripIllegalFilenameChars( $name ) {
3016         global $wgIllegalFileChars;
3017         $illegalFileChars = $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '';
3018         $name = preg_replace(
3019                 "/[^" . Title::legalChars() . "]" . $illegalFileChars . "/",
3020                 '-',
3021                 $name
3022         );
3023         // $wgIllegalFileChars may not include '/' and '\', so we still need to do this
3024         $name = wfBaseName( $name );
3025         return $name;
3026 }
3027
3028 /**
3029  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit
3030  *
3031  * @return int Resulting value of the memory limit.
3032  */
3033 function wfMemoryLimit() {
3034         global $wgMemoryLimit;
3035         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3036         if ( $memlimit != -1 ) {
3037                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3038                 if ( $conflimit == -1 ) {
3039                         wfDebug( "Removing PHP's memory limit\n" );
3040                         Wikimedia\suppressWarnings();
3041                         ini_set( 'memory_limit', $conflimit );
3042                         Wikimedia\restoreWarnings();
3043                         return $conflimit;
3044                 } elseif ( $conflimit > $memlimit ) {
3045                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3046                         Wikimedia\suppressWarnings();
3047                         ini_set( 'memory_limit', $conflimit );
3048                         Wikimedia\restoreWarnings();
3049                         return $conflimit;
3050                 }
3051         }
3052         return $memlimit;
3053 }
3054
3055 /**
3056  * Set PHP's time limit to the larger of php.ini or $wgTransactionalTimeLimit
3057  *
3058  * @return int Prior time limit
3059  * @since 1.26
3060  */
3061 function wfTransactionalTimeLimit() {
3062         global $wgTransactionalTimeLimit;
3063
3064         $timeLimit = ini_get( 'max_execution_time' );
3065         // Note that CLI scripts use 0
3066         if ( $timeLimit > 0 && $wgTransactionalTimeLimit > $timeLimit ) {
3067                 set_time_limit( $wgTransactionalTimeLimit );
3068         }
3069
3070         ignore_user_abort( true ); // ignore client disconnects
3071
3072         return $timeLimit;
3073 }
3074
3075 /**
3076  * Converts shorthand byte notation to integer form
3077  *
3078  * @param string $string
3079  * @param int $default Returned if $string is empty
3080  * @return int
3081  */
3082 function wfShorthandToInteger( $string = '', $default = -1 ) {
3083         $string = trim( $string );
3084         if ( $string === '' ) {
3085                 return $default;
3086         }
3087         $last = $string[strlen( $string ) - 1];
3088         $val = intval( $string );
3089         switch ( $last ) {
3090                 case 'g':
3091                 case 'G':
3092                         $val *= 1024;
3093                         // break intentionally missing
3094                 case 'm':
3095                 case 'M':
3096                         $val *= 1024;
3097                         // break intentionally missing
3098                 case 'k':
3099                 case 'K':
3100                         $val *= 1024;
3101         }
3102
3103         return $val;
3104 }
3105
3106 /**
3107  * Get the normalised IETF language tag
3108  * See unit test for examples.
3109  * See mediawiki.language.bcp47 for the JavaScript implementation.
3110  *
3111  * @deprecated since 1.31, use LanguageCode::bcp47() directly.
3112  *
3113  * @param string $code The language code.
3114  * @return string The language code which complying with BCP 47 standards.
3115  */
3116 function wfBCP47( $code ) {
3117         return LanguageCode::bcp47( $code );
3118 }
3119
3120 /**
3121  * Get a specific cache object.
3122  *
3123  * @param int|string $cacheType A CACHE_* constants, or other key in $wgObjectCaches
3124  * @return BagOStuff
3125  */
3126 function wfGetCache( $cacheType ) {
3127         return ObjectCache::getInstance( $cacheType );
3128 }
3129
3130 /**
3131  * Get the main cache object
3132  *
3133  * @return BagOStuff
3134  */
3135 function wfGetMainCache() {
3136         global $wgMainCacheType;
3137         return ObjectCache::getInstance( $wgMainCacheType );
3138 }
3139
3140 /**
3141  * Get the cache object used by the message cache
3142  *
3143  * @return BagOStuff
3144  */
3145 function wfGetMessageCacheStorage() {
3146         global $wgMessageCacheType;
3147         return ObjectCache::getInstance( $wgMessageCacheType );
3148 }
3149
3150 /**
3151  * Get the cache object used by the parser cache
3152  *
3153  * @deprecated since 1.30, use MediaWikiServices::getParserCache()->getCacheStorage()
3154  * @return BagOStuff
3155  */
3156 function wfGetParserCacheStorage() {
3157         global $wgParserCacheType;
3158         return ObjectCache::getInstance( $wgParserCacheType );
3159 }
3160
3161 /**
3162  * Call hook functions defined in $wgHooks
3163  *
3164  * @param string $event Event name
3165  * @param array $args Parameters passed to hook functions
3166  * @param string|null $deprecatedVersion Optionally mark hook as deprecated with version number
3167  *
3168  * @return bool True if no handler aborted the hook
3169  * @deprecated since 1.25 - use Hooks::run
3170  */
3171 function wfRunHooks( $event, array $args = [], $deprecatedVersion = null ) {
3172         wfDeprecated( __METHOD__, '1.25' );
3173         return Hooks::run( $event, $args, $deprecatedVersion );
3174 }
3175
3176 /**
3177  * Wrapper around php's unpack.
3178  *
3179  * @param string $format The format string (See php's docs)
3180  * @param string $data A binary string of binary data
3181  * @param int|bool $length The minimum length of $data or false. This is to
3182  *      prevent reading beyond the end of $data. false to disable the check.
3183  *
3184  * Also be careful when using this function to read unsigned 32 bit integer
3185  * because php might make it negative.
3186  *
3187  * @throws MWException If $data not long enough, or if unpack fails
3188  * @return array Associative array of the extracted data
3189  */
3190 function wfUnpack( $format, $data, $length = false ) {
3191         if ( $length !== false ) {
3192                 $realLen = strlen( $data );
3193                 if ( $realLen < $length ) {
3194                         throw new MWException( "Tried to use wfUnpack on a "
3195                                 . "string of length $realLen, but needed one "
3196                                 . "of at least length $length."
3197                         );
3198                 }
3199         }
3200
3201         Wikimedia\suppressWarnings();
3202         $result = unpack( $format, $data );
3203         Wikimedia\restoreWarnings();
3204
3205         if ( $result === false ) {
3206                 // If it cannot extract the packed data.
3207                 throw new MWException( "unpack could not unpack binary data" );
3208         }
3209         return $result;
3210 }
3211
3212 /**
3213  * Determine if an image exists on the 'bad image list'.
3214  *
3215  * The format of MediaWiki:Bad_image_list is as follows:
3216  *    * Only list items (lines starting with "*") are considered
3217  *    * The first link on a line must be a link to a bad image
3218  *    * Any subsequent links on the same line are considered to be exceptions,
3219  *      i.e. articles where the image may occur inline.
3220  *
3221  * @param string $name The image name to check
3222  * @param Title|bool $contextTitle The page on which the image occurs, if known
3223  * @param string $blacklist Wikitext of a file blacklist
3224  * @return bool
3225  */
3226 function wfIsBadImage( $name, $contextTitle = false, $blacklist = null ) {
3227         # Handle redirects; callers almost always hit wfFindFile() anyway,
3228         # so just use that method because it has a fast process cache.
3229         $file = wfFindFile( $name ); // get the final name
3230         $name = $file ? $file->getTitle()->getDBkey() : $name;
3231
3232         # Run the extension hook
3233         $bad = false;
3234         if ( !Hooks::run( 'BadImage', [ $name, &$bad ] ) ) {
3235                 return (bool)$bad;
3236         }
3237
3238         $cache = ObjectCache::getLocalServerInstance( 'hash' );
3239         $key = $cache->makeKey(
3240                 'bad-image-list', ( $blacklist === null ) ? 'default' : md5( $blacklist )
3241         );
3242         $badImages = $cache->get( $key );
3243
3244         if ( $badImages === false ) { // cache miss
3245                 if ( $blacklist === null ) {
3246                         $blacklist = wfMessage( 'bad_image_list' )->inContentLanguage()->plain(); // site list
3247                 }
3248                 # Build the list now
3249                 $badImages = [];
3250                 $lines = explode( "\n", $blacklist );
3251                 foreach ( $lines as $line ) {
3252                         # List items only
3253                         if ( substr( $line, 0, 1 ) !== '*' ) {
3254                                 continue;
3255                         }
3256
3257                         # Find all links
3258                         $m = [];
3259                         if ( !preg_match_all( '/\[\[:?(.*?)\]\]/', $line, $m ) ) {
3260                                 continue;
3261                         }
3262
3263                         $exceptions = [];
3264                         $imageDBkey = false;
3265                         foreach ( $m[1] as $i => $titleText ) {
3266                                 $title = Title::newFromText( $titleText );
3267                                 if ( !is_null( $title ) ) {
3268                                         if ( $i == 0 ) {
3269                                                 $imageDBkey = $title->getDBkey();
3270                                         } else {
3271                                                 $exceptions[$title->getPrefixedDBkey()] = true;
3272                                         }
3273                                 }
3274                         }
3275
3276                         if ( $imageDBkey !== false ) {
3277                                 $badImages[$imageDBkey] = $exceptions;
3278                         }
3279                 }
3280                 $cache->set( $key, $badImages, 60 );
3281         }
3282
3283         $contextKey = $contextTitle ? $contextTitle->getPrefixedDBkey() : false;
3284         $bad = isset( $badImages[$name] ) && !isset( $badImages[$name][$contextKey] );
3285
3286         return $bad;
3287 }
3288
3289 /**
3290  * Determine whether the client at a given source IP is likely to be able to
3291  * access the wiki via HTTPS.
3292  *
3293  * @param string $ip The IPv4/6 address in the normal human-readable form
3294  * @return bool
3295  */
3296 function wfCanIPUseHTTPS( $ip ) {
3297         $canDo = true;
3298         Hooks::run( 'CanIPUseHTTPS', [ $ip, &$canDo ] );
3299         return !!$canDo;
3300 }
3301
3302 /**
3303  * Determine input string is represents as infinity
3304  *
3305  * @param string $str The string to determine
3306  * @return bool
3307  * @since 1.25
3308  */
3309 function wfIsInfinity( $str ) {
3310         // These are hardcoded elsewhere in MediaWiki (e.g. mediawiki.special.block.js).
3311         $infinityValues = [ 'infinite', 'indefinite', 'infinity', 'never' ];
3312         return in_array( $str, $infinityValues );
3313 }
3314
3315 /**
3316  * Returns true if these thumbnail parameters match one that MediaWiki
3317  * requests from file description pages and/or parser output.
3318  *
3319  * $params is considered non-standard if they involve a non-standard
3320  * width or any non-default parameters aside from width and page number.
3321  * The number of possible files with standard parameters is far less than
3322  * that of all combinations; rate-limiting for them can thus be more generious.
3323  *
3324  * @param File $file
3325  * @param array $params
3326  * @return bool
3327  * @since 1.24 Moved from thumb.php to GlobalFunctions in 1.25
3328  */
3329 function wfThumbIsStandard( File $file, array $params ) {
3330         global $wgThumbLimits, $wgImageLimits, $wgResponsiveImages;
3331
3332         $multipliers = [ 1 ];
3333         if ( $wgResponsiveImages ) {
3334                 // These available sizes are hardcoded currently elsewhere in MediaWiki.
3335                 // @see Linker::processResponsiveImages
3336                 $multipliers[] = 1.5;
3337                 $multipliers[] = 2;
3338         }
3339
3340         $handler = $file->getHandler();
3341         if ( !$handler || !isset( $params['width'] ) ) {
3342                 return false;
3343         }
3344
3345         $basicParams = [];
3346         if ( isset( $params['page'] ) ) {
3347                 $basicParams['page'] = $params['page'];
3348         }
3349
3350         $thumbLimits = [];
3351         $imageLimits = [];
3352         // Expand limits to account for multipliers
3353         foreach ( $multipliers as $multiplier ) {
3354                 $thumbLimits = array_merge( $thumbLimits, array_map(
3355                         function ( $width ) use ( $multiplier ) {
3356                                 return round( $width * $multiplier );
3357                         }, $wgThumbLimits )
3358                 );
3359                 $imageLimits = array_merge( $imageLimits, array_map(
3360                         function ( $pair ) use ( $multiplier ) {
3361                                 return [
3362                                         round( $pair[0] * $multiplier ),
3363                                         round( $pair[1] * $multiplier ),
3364                                 ];
3365                         }, $wgImageLimits )
3366                 );
3367         }
3368
3369         // Check if the width matches one of $wgThumbLimits
3370         if ( in_array( $params['width'], $thumbLimits ) ) {
3371                 $normalParams = $basicParams + [ 'width' => $params['width'] ];
3372                 // Append any default values to the map (e.g. "lossy", "lossless", ...)
3373                 $handler->normaliseParams( $file, $normalParams );
3374         } else {
3375                 // If not, then check if the width matchs one of $wgImageLimits
3376                 $match = false;
3377                 foreach ( $imageLimits as $pair ) {
3378                         $normalParams = $basicParams + [ 'width' => $pair[0], 'height' => $pair[1] ];
3379                         // Decide whether the thumbnail should be scaled on width or height.
3380                         // Also append any default values to the map (e.g. "lossy", "lossless", ...)
3381                         $handler->normaliseParams( $file, $normalParams );
3382                         // Check if this standard thumbnail size maps to the given width
3383                         if ( $normalParams['width'] == $params['width'] ) {
3384                                 $match = true;
3385                                 break;
3386                         }
3387                 }
3388                 if ( !$match ) {
3389                         return false; // not standard for description pages
3390                 }
3391         }
3392
3393         // Check that the given values for non-page, non-width, params are just defaults
3394         foreach ( $params as $key => $value ) {
3395                 if ( !isset( $normalParams[$key] ) || $normalParams[$key] != $value ) {
3396                         return false;
3397                 }
3398         }
3399
3400         return true;
3401 }
3402
3403 /**
3404  * Merges two (possibly) 2 dimensional arrays into the target array ($baseArray).
3405  *
3406  * Values that exist in both values will be combined with += (all values of the array
3407  * of $newValues will be added to the values of the array of $baseArray, while values,
3408  * that exists in both, the value of $baseArray will be used).
3409  *
3410  * @param array $baseArray The array where you want to add the values of $newValues to
3411  * @param array $newValues An array with new values
3412  * @return array The combined array
3413  * @since 1.26
3414  */
3415 function wfArrayPlus2d( array $baseArray, array $newValues ) {
3416         // First merge items that are in both arrays
3417         foreach ( $baseArray as $name => &$groupVal ) {
3418                 if ( isset( $newValues[$name] ) ) {
3419                         $groupVal += $newValues[$name];
3420                 }
3421         }
3422         // Now add items that didn't exist yet
3423         $baseArray += $newValues;
3424
3425         return $baseArray;
3426 }
3427
3428 /**
3429  * Get system resource usage of current request context.
3430  * Invokes the getrusage(2) system call, requesting RUSAGE_SELF if on PHP5
3431  * or RUSAGE_THREAD if on HHVM. Returns false if getrusage is not available.
3432  *
3433  * @since 1.24
3434  * @return array|bool Resource usage data or false if no data available.
3435  */
3436 function wfGetRusage() {
3437         if ( !function_exists( 'getrusage' ) ) {
3438                 return false;
3439         } elseif ( defined( 'HHVM_VERSION' ) && PHP_OS === 'Linux' ) {
3440                 return getrusage( 2 /* RUSAGE_THREAD */ );
3441         } else {
3442                 return getrusage( 0 /* RUSAGE_SELF */ );
3443         }
3444 }