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 use Wikimedia\WrappedString;
  35
  36 /**
  37  * Load an extension
  38  *
  39  * This queues an extension to be loaded through
  40  * the ExtensionRegistry system.
  41  *
  42  * @param string $ext Name of the extension to load
  43  * @param string|null $path Absolute path of where to find the extension.json file
  44  * @since 1.25
  45  */
  46 function wfLoadExtension( $ext, $path = null ) {
  47         if ( !$path ) {
  48                 global $wgExtensionDirectory;
  49                 $path = "$wgExtensionDirectory/$ext/extension.json";
  50         }
  51         ExtensionRegistry::getInstance()->queue( $path );
  52 }
  53
  54 /**
  55  * Load multiple extensions at once
  56  *
  57  * Same as wfLoadExtension, but more efficient if you
  58  * are loading multiple extensions.
  59  *
  60  * If you want to specify custom paths, you should interact with
  61  * ExtensionRegistry directly.
  62  *
  63  * @see wfLoadExtension
  64  * @param string[] $exts Array of extension names to load
  65  * @since 1.25
  66  */
  67 function wfLoadExtensions( array $exts ) {
  68         global $wgExtensionDirectory;
  69         $registry = ExtensionRegistry::getInstance();
  70         foreach ( $exts as $ext ) {
  71                 $registry->queue( "$wgExtensionDirectory/$ext/extension.json" );
  72         }
  73 }
  74
  75 /**
  76  * Load a skin
  77  *
  78  * @see wfLoadExtension
  79  * @param string $skin Name of the extension to load
  80  * @param string|null $path Absolute path of where to find the skin.json file
  81  * @since 1.25
  82  */
  83 function wfLoadSkin( $skin, $path = null ) {
  84         if ( !$path ) {
  85                 global $wgStyleDirectory;
  86                 $path = "$wgStyleDirectory/$skin/skin.json";
  87         }
  88         ExtensionRegistry::getInstance()->queue( $path );
  89 }
  90
  91 /**
  92  * Load multiple skins at once
  93  *
  94  * @see wfLoadExtensions
  95  * @param string[] $skins Array of extension names to load
  96  * @since 1.25
  97  */
  98 function wfLoadSkins( array $skins ) {
  99         global $wgStyleDirectory;
 100         $registry = ExtensionRegistry::getInstance();
 101         foreach ( $skins as $skin ) {
 102                 $registry->queue( "$wgStyleDirectory/$skin/skin.json" );
 103         }
 104 }
 105
 106 /**
 107  * Like array_diff( $a, $b ) except that it works with two-dimensional arrays.
 108  * @param array $a
 109  * @param array $b
 110  * @return array
 111  */
 112 function wfArrayDiff2( $a, $b ) {
 113         return array_udiff( $a, $b, 'wfArrayDiff2_cmp' );
 114 }
 115
 116 /**
 117  * @param array|string $a
 118  * @param array|string $b
 119  * @return int
 120  */
 121 function wfArrayDiff2_cmp( $a, $b ) {
 122         if ( is_string( $a ) && is_string( $b ) ) {
 123                 return strcmp( $a, $b );
 124         } elseif ( count( $a ) !== count( $b ) ) {
 125                 return count( $a ) <=> count( $b );
 126         } else {
 127                 reset( $a );
 128                 reset( $b );
 129                 while ( key( $a ) !== null && key( $b ) !== null ) {
 130                         $valueA = current( $a );
 131                         $valueB = current( $b );
 132                         $cmp = strcmp( $valueA, $valueB );
 133                         if ( $cmp !== 0 ) {
 134                                 return $cmp;
 135                         }
 136                         next( $a );
 137                         next( $b );
 138                 }
 139                 return 0;
 140         }
 141 }
 142
 143 /**
 144  * @deprecated since 1.32, use array_filter() with ARRAY_FILTER_USE_BOTH directly
 145  *
 146  * @param array $arr
 147  * @param callable $callback Will be called with the array value and key (in that order) and
 148  *   should return a bool which will determine whether the array element is kept.
 149  * @return array
 150  */
 151 function wfArrayFilter( array $arr, callable $callback ) {
 152         return array_filter( $arr, $callback, ARRAY_FILTER_USE_BOTH );
 153 }
 154
 155 /**
 156  * @deprecated since 1.32, use array_filter() with ARRAY_FILTER_USE_KEY directly
 157  *
 158  * @param array $arr
 159  * @param callable $callback Will be called with the array key and should return a bool which
 160  *   will determine whether the array element is kept.
 161  * @return array
 162  */
 163 function wfArrayFilterByKey( array $arr, callable $callback ) {
 164         return array_filter( $arr, $callback, ARRAY_FILTER_USE_KEY );
 165 }
 166
 167 /**
 168  * Appends to second array if $value differs from that in $default
 169  *
 170  * @param string|int $key
 171  * @param mixed $value
 172  * @param mixed $default
 173  * @param array &$changed Array to alter
 174  * @throws MWException
 175  */
 176 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
 177         if ( is_null( $changed ) ) {
 178                 throw new MWException( 'GlobalFunctions::wfAppendToArrayIfNotDefault got null' );
 179         }
 180         if ( $default[$key] !== $value ) {
 181                 $changed[$key] = $value;
 182         }
 183 }
 184
 185 /**
 186  * Merge arrays in the style of getUserPermissionsErrors, with duplicate removal
 187  * e.g.
 188  *     wfMergeErrorArrays(
 189  *       [ [ 'x' ] ],
 190  *       [ [ 'x', '2' ] ],
 191  *       [ [ 'x' ] ],
 192  *       [ [ 'y' ] ]
 193  *     );
 194  * returns:
 195  *     [
 196  *       [ 'x', '2' ],
 197  *       [ 'x' ],
 198  *       [ 'y' ]
 199  *     ]
 200  *
 201  * @param array $array1,...
 202  * @return array
 203  */
 204 function wfMergeErrorArrays( /*...*/ ) {
 205         $args = func_get_args();
 206         $out = [];
 207         foreach ( $args as $errors ) {
 208                 foreach ( $errors as $params ) {
 209                         $originalParams = $params;
 210                         if ( $params[0] instanceof MessageSpecifier ) {
 211                                 $msg = $params[0];
 212                                 $params = array_merge( [ $msg->getKey() ], $msg->getParams() );
 213                         }
 214                         # @todo FIXME: Sometimes get nested arrays for $params,
 215                         # which leads to E_NOTICEs
 216                         $spec = implode( "\t", $params );
 217                         $out[$spec] = $originalParams;
 218                 }
 219         }
 220         return array_values( $out );
 221 }
 222
 223 /**
 224  * Insert array into another array after the specified *KEY*
 225  *
 226  * @param array $array The array.
 227  * @param array $insert The array to insert.
 228  * @param mixed $after The key to insert after
 229  * @return array
 230  */
 231 function wfArrayInsertAfter( array $array, array $insert, $after ) {
 232         // Find the offset of the element to insert after.
 233         $keys = array_keys( $array );
 234         $offsetByKey = array_flip( $keys );
 235
 236         $offset = $offsetByKey[$after];
 237
 238         // Insert at the specified offset
 239         $before = array_slice( $array, 0, $offset + 1, true );
 240         $after = array_slice( $array, $offset + 1, count( $array ) - $offset, true );
 241
 242         $output = $before + $insert + $after;
 243
 244         return $output;
 245 }
 246
 247 /**
 248  * Recursively converts the parameter (an object) to an array with the same data
 249  *
 250  * @param object|array $objOrArray
 251  * @param bool $recursive
 252  * @return array
 253  */
 254 function wfObjectToArray( $objOrArray, $recursive = true ) {
 255         $array = [];
 256         if ( is_object( $objOrArray ) ) {
 257                 $objOrArray = get_object_vars( $objOrArray );
 258         }
 259         foreach ( $objOrArray as $key => $value ) {
 260                 if ( $recursive && ( is_object( $value ) || is_array( $value ) ) ) {
 261                         $value = wfObjectToArray( $value );
 262                 }
 263
 264                 $array[$key] = $value;
 265         }
 266
 267         return $array;
 268 }
 269
 270 /**
 271  * Get a random decimal value between 0 and 1, in a way
 272  * not likely to give duplicate values for any realistic
 273  * number of articles.
 274  *
 275  * @note This is designed for use in relation to Special:RandomPage
 276  *       and the page_random database field.
 277  *
 278  * @return string
 279  */
 280 function wfRandom() {
 281         // The maximum random value is "only" 2^31-1, so get two random
 282         // values to reduce the chance of dupes
 283         $max = mt_getrandmax() + 1;
 284         $rand = number_format( ( mt_rand() * $max + mt_rand() ) / $max / $max, 12, '.', '' );
 285         return $rand;
 286 }
 287
 288 /**
 289  * Get a random string containing a number of pseudo-random hex characters.
 290  *
 291  * @note This is not secure, if you are trying to generate some sort
 292  *       of token please use MWCryptRand instead.
 293  *
 294  * @param int $length The length of the string to generate
 295  * @return string
 296  * @since 1.20
 297  */
 298 function wfRandomString( $length = 32 ) {
 299         $str = '';
 300         for ( $n = 0; $n < $length; $n += 7 ) {
 301                 $str .= sprintf( '%07x', mt_rand() & 0xfffffff );
 302         }
 303         return substr( $str, 0, $length );
 304 }
 305
 306 /**
 307  * We want some things to be included as literal characters in our title URLs
 308  * for prettiness, which urlencode encodes by default.  According to RFC 1738,
 309  * all of the following should be safe:
 310  *
 311  * ;:@&=$-_.+!*'(),
 312  *
 313  * RFC 1738 says ~ is unsafe, however RFC 3986 considers it an unreserved
 314  * character which should not be encoded. More importantly, google chrome
 315  * always converts %7E back to ~, and converting it in this function can
 316  * cause a redirect loop (T105265).
 317  *
 318  * But + is not safe because it's used to indicate a space; &= are only safe in
 319  * paths and not in queries (and we don't distinguish here); ' seems kind of
 320  * scary; and urlencode() doesn't touch -_. to begin with.  Plus, although /
 321  * is reserved, we don't care.  So the list we unescape is:
 322  *
 323  * ;:@$!*(),/~
 324  *
 325  * However, IIS7 redirects fail when the url contains a colon (see T24709),
 326  * so no fancy : for IIS7.
 327  *
 328  * %2F in the page titles seems to fatally break for some reason.
 329  *
 330  * @param string $s
 331  * @return string
 332  */
 333 function wfUrlencode( $s ) {
 334         static $needle;
 335
 336         if ( is_null( $s ) ) {
 337                 $needle = null;
 338                 return '';
 339         }
 340
 341         if ( is_null( $needle ) ) {
 342                 $needle = [ '%3B', '%40', '%24', '%21', '%2A', '%28', '%29', '%2C', '%2F', '%7E' ];
 343                 if ( !isset( $_SERVER['SERVER_SOFTWARE'] ) ||
 344                         ( strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/7' ) === false )
 345                 ) {
 346                         $needle[] = '%3A';
 347                 }
 348         }
 349
 350         $s = urlencode( $s );
 351         $s = str_ireplace(
 352                 $needle,
 353                 [ ';', '@', '$', '!', '*', '(', ')', ',', '/', '~', ':' ],
 354                 $s
 355         );
 356
 357         return $s;
 358 }
 359
 360 /**
 361  * This function takes one or two arrays as input, and returns a CGI-style string, e.g.
 362  * "days=7&limit=100". Options in the first array override options in the second.
 363  * Options set to null or false will not be output.
 364  *
 365  * @param array $array1 ( String|Array )
 366  * @param array|null $array2 ( String|Array )
 367  * @param string $prefix
 368  * @return string
 369  */
 370 function wfArrayToCgi( $array1, $array2 = null, $prefix = '' ) {
 371         if ( !is_null( $array2 ) ) {
 372                 $array1 = $array1 + $array2;
 373         }
 374
 375         $cgi = '';
 376         foreach ( $array1 as $key => $value ) {
 377                 if ( !is_null( $value ) && $value !== false ) {
 378                         if ( $cgi != '' ) {
 379                                 $cgi .= '&';
 380                         }
 381                         if ( $prefix !== '' ) {
 382                                 $key = $prefix . "[$key]";
 383                         }
 384                         if ( is_array( $value ) ) {
 385                                 $firstTime = true;
 386                                 foreach ( $value as $k => $v ) {
 387                                         $cgi .= $firstTime ? '' : '&';
 388                                         if ( is_array( $v ) ) {
 389                                                 $cgi .= wfArrayToCgi( $v, null, $key . "[$k]" );
 390                                         } else {
 391                                                 $cgi .= urlencode( $key . "[$k]" ) . '=' . urlencode( $v );
 392                                         }
 393                                         $firstTime = false;
 394                                 }
 395                         } else {
 396                                 if ( is_object( $value ) ) {
 397                                         $value = $value->__toString();
 398                                 }
 399                                 $cgi .= urlencode( $key ) . '=' . urlencode( $value );
 400                         }
 401                 }
 402         }
 403         return $cgi;
 404 }
 405
 406 /**
 407  * This is the logical opposite of wfArrayToCgi(): it accepts a query string as
 408  * its argument and returns the same string in array form.  This allows compatibility
 409  * with legacy functions that accept raw query strings instead of nice
 410  * arrays.  Of course, keys and values are urldecode()d.
 411  *
 412  * @param string $query Query string
 413  * @return string[] Array version of input
 414  */
 415 function wfCgiToArray( $query ) {
 416         if ( isset( $query[0] ) && $query[0] == '?' ) {
 417                 $query = substr( $query, 1 );
 418         }
 419         $bits = explode( '&', $query );
 420         $ret = [];
 421         foreach ( $bits as $bit ) {
 422                 if ( $bit === '' ) {
 423                         continue;
 424                 }
 425                 if ( strpos( $bit, '=' ) === false ) {
 426                         // Pieces like &qwerty become 'qwerty' => '' (at least this is what php does)
 427                         $key = $bit;
 428                         $value = '';
 429                 } else {
 430                         list( $key, $value ) = explode( '=', $bit );
 431                 }
 432                 $key = urldecode( $key );
 433                 $value = urldecode( $value );
 434                 if ( strpos( $key, '[' ) !== false ) {
 435                         $keys = array_reverse( explode( '[', $key ) );
 436                         $key = array_pop( $keys );
 437                         $temp = $value;
 438                         foreach ( $keys as $k ) {
 439                                 $k = substr( $k, 0, -1 );
 440                                 $temp = [ $k => $temp ];
 441                         }
 442                         if ( isset( $ret[$key] ) ) {
 443                                 $ret[$key] = array_merge( $ret[$key], $temp );
 444                         } else {
 445                                 $ret[$key] = $temp;
 446                         }
 447                 } else {
 448                         $ret[$key] = $value;
 449                 }
 450         }
 451         return $ret;
 452 }
 453
 454 /**
 455  * Append a query string to an existing URL, which may or may not already
 456  * have query string parameters already. If so, they will be combined.
 457  *
 458  * @param string $url
 459  * @param string|string[] $query String or associative array
 460  * @return string
 461  */
 462 function wfAppendQuery( $url, $query ) {
 463         if ( is_array( $query ) ) {
 464                 $query = wfArrayToCgi( $query );
 465         }
 466         if ( $query != '' ) {
 467                 // Remove the fragment, if there is one
 468                 $fragment = false;
 469                 $hashPos = strpos( $url, '#' );
 470                 if ( $hashPos !== false ) {
 471                         $fragment = substr( $url, $hashPos );
 472                         $url = substr( $url, 0, $hashPos );
 473                 }
 474
 475                 // Add parameter
 476                 if ( false === strpos( $url, '?' ) ) {
 477                         $url .= '?';
 478                 } else {
 479                         $url .= '&';
 480                 }
 481                 $url .= $query;
 482
 483                 // Put the fragment back
 484                 if ( $fragment !== false ) {
 485                         $url .= $fragment;
 486                 }
 487         }
 488         return $url;
 489 }
 490
 491 /**
 492  * Expand a potentially local URL to a fully-qualified URL. Assumes $wgServer
 493  * is correct.
 494  *
 495  * The meaning of the PROTO_* constants is as follows:
 496  * PROTO_HTTP: Output a URL starting with http://
 497  * PROTO_HTTPS: Output a URL starting with https://
 498  * PROTO_RELATIVE: Output a URL starting with // (protocol-relative URL)
 499  * PROTO_CURRENT: Output a URL starting with either http:// or https:// , depending
 500  *    on which protocol was used for the current incoming request
 501  * PROTO_CANONICAL: For URLs without a domain, like /w/index.php , use $wgCanonicalServer.
 502  *    For protocol-relative URLs, use the protocol of $wgCanonicalServer
 503  * PROTO_INTERNAL: Like PROTO_CANONICAL, but uses $wgInternalServer instead of $wgCanonicalServer
 504  *
 505  * @todo this won't work with current-path-relative URLs
 506  * like "subdir/foo.html", etc.
 507  *
 508  * @param string $url Either fully-qualified or a local path + query
 509  * @param string|int|null $defaultProto One of the PROTO_* constants. Determines the
 510  *    protocol to use if $url or $wgServer is protocol-relative
 511  * @return string|false Fully-qualified URL, current-path-relative URL or false if
 512  *    no valid URL can be constructed
 513  */
 514 function wfExpandUrl( $url, $defaultProto = PROTO_CURRENT ) {
 515         global $wgServer, $wgCanonicalServer, $wgInternalServer, $wgRequest,
 516                 $wgHttpsPort;
 517         if ( $defaultProto === PROTO_CANONICAL ) {
 518                 $serverUrl = $wgCanonicalServer;
 519         } elseif ( $defaultProto === PROTO_INTERNAL && $wgInternalServer !== false ) {
 520                 // Make $wgInternalServer fall back to $wgServer if not set
 521                 $serverUrl = $wgInternalServer;
 522         } else {
 523                 $serverUrl = $wgServer;
 524                 if ( $defaultProto === PROTO_CURRENT ) {
 525                         $defaultProto = $wgRequest->getProtocol() . '://';
 526                 }
 527         }
 528
 529         // Analyze $serverUrl to obtain its protocol
 530         $bits = wfParseUrl( $serverUrl );
 531         $serverHasProto = $bits && $bits['scheme'] != '';
 532
 533         if ( $defaultProto === PROTO_CANONICAL || $defaultProto === PROTO_INTERNAL ) {
 534                 if ( $serverHasProto ) {
 535                         $defaultProto = $bits['scheme'] . '://';
 536                 } else {
 537                         // $wgCanonicalServer or $wgInternalServer doesn't have a protocol.
 538                         // This really isn't supposed to happen. Fall back to HTTP in this
 539                         // ridiculous case.
 540                         $defaultProto = PROTO_HTTP;
 541                 }
 542         }
 543
 544         $defaultProtoWithoutSlashes = substr( $defaultProto, 0, -2 );
 545
 546         if ( substr( $url, 0, 2 ) == '//' ) {
 547                 $url = $defaultProtoWithoutSlashes . $url;
 548         } elseif ( substr( $url, 0, 1 ) == '/' ) {
 549                 // If $serverUrl is protocol-relative, prepend $defaultProtoWithoutSlashes,
 550                 // otherwise leave it alone.
 551                 if ( $serverHasProto ) {
 552                         $url = $serverUrl . $url;
 553                 } else {
 554                         // If an HTTPS URL is synthesized from a protocol-relative $wgServer, allow the
 555                         // user to override the port number (T67184)
 556                         if ( $defaultProto === PROTO_HTTPS && $wgHttpsPort != 443 ) {
 557                                 if ( isset( $bits['port'] ) ) {
 558                                         throw new Exception( 'A protocol-relative $wgServer may not contain a port number' );
 559                                 }
 560                                 $url = $defaultProtoWithoutSlashes . $serverUrl . ':' . $wgHttpsPort . $url;
 561                         } else {
 562                                 $url = $defaultProtoWithoutSlashes . $serverUrl . $url;
 563                         }
 564                 }
 565         }
 566
 567         $bits = wfParseUrl( $url );
 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  * Get the wiki's "server", i.e. the protocol and host part of the URL, with a
 586  * protocol specified using a PROTO_* constant as in wfExpandUrl()
 587  *
 588  * @since 1.32
 589  * @param string|int|null $proto One of the PROTO_* constants.
 590  * @return string The URL
 591  */
 592 function wfGetServerUrl( $proto ) {
 593         $url = wfExpandUrl( '/', $proto );
 594         return substr( $url, 0, -1 );
 595 }
 596
 597 /**
 598  * This function will reassemble a URL parsed with wfParseURL.  This is useful
 599  * if you need to edit part of a URL and put it back together.
 600  *
 601  * This is the basic structure used (brackets contain keys for $urlParts):
 602  * [scheme][delimiter][user]:[pass]@[host]:[port][path]?[query]#[fragment]
 603  *
 604  * @todo Need to integrate this into wfExpandUrl (see T34168)
 605  *
 606  * @since 1.19
 607  * @param array $urlParts URL parts, as output from wfParseUrl
 608  * @return string URL assembled from its component parts
 609  */
 610 function wfAssembleUrl( $urlParts ) {
 611         $result = '';
 612
 613         if ( isset( $urlParts['delimiter'] ) ) {
 614                 if ( isset( $urlParts['scheme'] ) ) {
 615                         $result .= $urlParts['scheme'];
 616                 }
 617
 618                 $result .= $urlParts['delimiter'];
 619         }
 620
 621         if ( isset( $urlParts['host'] ) ) {
 622                 if ( isset( $urlParts['user'] ) ) {
 623                         $result .= $urlParts['user'];
 624                         if ( isset( $urlParts['pass'] ) ) {
 625                                 $result .= ':' . $urlParts['pass'];
 626                         }
 627                         $result .= '@';
 628                 }
 629
 630                 $result .= $urlParts['host'];
 631
 632                 if ( isset( $urlParts['port'] ) ) {
 633                         $result .= ':' . $urlParts['port'];
 634                 }
 635         }
 636
 637         if ( isset( $urlParts['path'] ) ) {
 638                 $result .= $urlParts['path'];
 639         }
 640
 641         if ( isset( $urlParts['query'] ) ) {
 642                 $result .= '?' . $urlParts['query'];
 643         }
 644
 645         if ( isset( $urlParts['fragment'] ) ) {
 646                 $result .= '#' . $urlParts['fragment'];
 647         }
 648
 649         return $result;
 650 }
 651
 652 /**
 653  * Remove all dot-segments in the provided URL path.  For example,
 654  * '/a/./b/../c/' becomes '/a/c/'.  For details on the algorithm, please see
 655  * RFC3986 section 5.2.4.
 656  *
 657  * @todo Need to integrate this into wfExpandUrl (see T34168)
 658  *
 659  * @since 1.19
 660  *
 661  * @param string $urlPath URL path, potentially containing dot-segments
 662  * @return string URL path with all dot-segments removed
 663  */
 664 function wfRemoveDotSegments( $urlPath ) {
 665         $output = '';
 666         $inputOffset = 0;
 667         $inputLength = strlen( $urlPath );
 668
 669         while ( $inputOffset < $inputLength ) {
 670                 $prefixLengthOne = substr( $urlPath, $inputOffset, 1 );
 671                 $prefixLengthTwo = substr( $urlPath, $inputOffset, 2 );
 672                 $prefixLengthThree = substr( $urlPath, $inputOffset, 3 );
 673                 $prefixLengthFour = substr( $urlPath, $inputOffset, 4 );
 674                 $trimOutput = false;
 675
 676                 if ( $prefixLengthTwo == './' ) {
 677                         # Step A, remove leading "./"
 678                         $inputOffset += 2;
 679                 } elseif ( $prefixLengthThree == '../' ) {
 680                         # Step A, remove leading "../"
 681                         $inputOffset += 3;
 682                 } elseif ( ( $prefixLengthTwo == '/.' ) && ( $inputOffset + 2 == $inputLength ) ) {
 683                         # Step B, replace leading "/.$" with "/"
 684                         $inputOffset += 1;
 685                         $urlPath[$inputOffset] = '/';
 686                 } elseif ( $prefixLengthThree == '/./' ) {
 687                         # Step B, replace leading "/./" with "/"
 688                         $inputOffset += 2;
 689                 } elseif ( $prefixLengthThree == '/..' && ( $inputOffset + 3 == $inputLength ) ) {
 690                         # Step C, replace leading "/..$" with "/" and
 691                         # remove last path component in output
 692                         $inputOffset += 2;
 693                         $urlPath[$inputOffset] = '/';
 694                         $trimOutput = true;
 695                 } elseif ( $prefixLengthFour == '/../' ) {
 696                         # Step C, replace leading "/../" with "/" and
 697                         # remove last path component in output
 698                         $inputOffset += 3;
 699                         $trimOutput = true;
 700                 } elseif ( ( $prefixLengthOne == '.' ) && ( $inputOffset + 1 == $inputLength ) ) {
 701                         # Step D, remove "^.$"
 702                         $inputOffset += 1;
 703                 } elseif ( ( $prefixLengthTwo == '..' ) && ( $inputOffset + 2 == $inputLength ) ) {
 704                         # Step D, remove "^..$"
 705                         $inputOffset += 2;
 706                 } else {
 707                         # Step E, move leading path segment to output
 708                         if ( $prefixLengthOne == '/' ) {
 709                                 $slashPos = strpos( $urlPath, '/', $inputOffset + 1 );
 710                         } else {
 711                                 $slashPos = strpos( $urlPath, '/', $inputOffset );
 712                         }
 713                         if ( $slashPos === false ) {
 714                                 $output .= substr( $urlPath, $inputOffset );
 715                                 $inputOffset = $inputLength;
 716                         } else {
 717                                 $output .= substr( $urlPath, $inputOffset, $slashPos - $inputOffset );
 718                                 $inputOffset += $slashPos - $inputOffset;
 719                         }
 720                 }
 721
 722                 if ( $trimOutput ) {
 723                         $slashPos = strrpos( $output, '/' );
 724                         if ( $slashPos === false ) {
 725                                 $output = '';
 726                         } else {
 727                                 $output = substr( $output, 0, $slashPos );
 728                         }
 729                 }
 730         }
 731
 732         return $output;
 733 }
 734
 735 /**
 736  * Returns a regular expression of url protocols
 737  *
 738  * @param bool $includeProtocolRelative If false, remove '//' from the returned protocol list.
 739  *        DO NOT USE this directly, use wfUrlProtocolsWithoutProtRel() instead
 740  * @return string
 741  */
 742 function wfUrlProtocols( $includeProtocolRelative = true ) {
 743         global $wgUrlProtocols;
 744
 745         // Cache return values separately based on $includeProtocolRelative
 746         static $withProtRel = null, $withoutProtRel = null;
 747         $cachedValue = $includeProtocolRelative ? $withProtRel : $withoutProtRel;
 748         if ( !is_null( $cachedValue ) ) {
 749                 return $cachedValue;
 750         }
 751
 752         // Support old-style $wgUrlProtocols strings, for backwards compatibility
 753         // with LocalSettings files from 1.5
 754         if ( is_array( $wgUrlProtocols ) ) {
 755                 $protocols = [];
 756                 foreach ( $wgUrlProtocols as $protocol ) {
 757                         // Filter out '//' if !$includeProtocolRelative
 758                         if ( $includeProtocolRelative || $protocol !== '//' ) {
 759                                 $protocols[] = preg_quote( $protocol, '/' );
 760                         }
 761                 }
 762
 763                 $retval = implode( '|', $protocols );
 764         } else {
 765                 // Ignore $includeProtocolRelative in this case
 766                 // This case exists for pre-1.6 compatibility, and we can safely assume
 767                 // that '//' won't appear in a pre-1.6 config because protocol-relative
 768                 // URLs weren't supported until 1.18
 769                 $retval = $wgUrlProtocols;
 770         }
 771
 772         // Cache return value
 773         if ( $includeProtocolRelative ) {
 774                 $withProtRel = $retval;
 775         } else {
 776                 $withoutProtRel = $retval;
 777         }
 778         return $retval;
 779 }
 780
 781 /**
 782  * Like wfUrlProtocols(), but excludes '//' from the protocol list. Use this if
 783  * you need a regex that matches all URL protocols but does not match protocol-
 784  * relative URLs
 785  * @return string
 786  */
 787 function wfUrlProtocolsWithoutProtRel() {
 788         return wfUrlProtocols( false );
 789 }
 790
 791 /**
 792  * parse_url() work-alike, but non-broken.  Differences:
 793  *
 794  * 1) Does not raise warnings on bad URLs (just returns false).
 795  * 2) Handles protocols that don't use :// (e.g., mailto: and news:, as well as
 796  *    protocol-relative URLs) correctly.
 797  * 3) Adds a "delimiter" element to the array (see (2)).
 798  * 4) Verifies that the protocol is on the $wgUrlProtocols whitelist.
 799  * 5) Rejects some invalid URLs that parse_url doesn't, e.g. the empty string or URLs starting with
 800  *    a line feed character.
 801  *
 802  * @param string $url A URL to parse
 803  * @return string[]|bool Bits of the URL in an associative array, or false on failure.
 804  *   Possible fields:
 805  *   - scheme: URI scheme (protocol), e.g. 'http', 'mailto'. Lowercase, always present, but can
 806  *       be an empty string for protocol-relative URLs.
 807  *   - delimiter: either '://', ':' or '//'. Always present.
 808  *   - host: domain name / IP. Always present, but could be an empty string, e.g. for file: URLs.
 809  *   - user: user name, e.g. for HTTP Basic auth URLs such as http://user:pass@example.com/
 810  *       Missing when there is no username.
 811  *   - pass: password, same as above.
 812  *   - path: path including the leading /. Will be missing when empty (e.g. 'http://example.com')
 813  *   - query: query string (as a string; see wfCgiToArray() for parsing it), can be missing.
 814  *   - fragment: the part after #, can be missing.
 815  */
 816 function wfParseUrl( $url ) {
 817         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
 818
 819         // Protocol-relative URLs are handled really badly by parse_url(). It's so
 820         // bad that the easiest way to handle them is to just prepend 'http:' and
 821         // strip the protocol out later.
 822         $wasRelative = substr( $url, 0, 2 ) == '//';
 823         if ( $wasRelative ) {
 824                 $url = "http:$url";
 825         }
 826         Wikimedia\suppressWarnings();
 827         $bits = parse_url( $url );
 828         Wikimedia\restoreWarnings();
 829         // parse_url() returns an array without scheme for some invalid URLs, e.g.
 830         // parse_url("%0Ahttp://example.com") == [ 'host' => '%0Ahttp', 'path' => 'example.com' ]
 831         if ( !$bits || !isset( $bits['scheme'] ) ) {
 832                 return false;
 833         }
 834
 835         // parse_url() incorrectly handles schemes case-sensitively. Convert it to lowercase.
 836         $bits['scheme'] = strtolower( $bits['scheme'] );
 837
 838         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
 839         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
 840                 $bits['delimiter'] = '://';
 841         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
 842                 $bits['delimiter'] = ':';
 843                 // parse_url detects for news: and mailto: the host part of an url as path
 844                 // We have to correct this wrong detection
 845                 if ( isset( $bits['path'] ) ) {
 846                         $bits['host'] = $bits['path'];
 847                         $bits['path'] = '';
 848                 }
 849         } else {
 850                 return false;
 851         }
 852
 853         /* Provide an empty host for eg. file:/// urls (see T30627) */
 854         if ( !isset( $bits['host'] ) ) {
 855                 $bits['host'] = '';
 856
 857                 // See T47069
 858                 if ( isset( $bits['path'] ) ) {
 859                         /* parse_url loses the third / for file:///c:/ urls (but not on variants) */
 860                         if ( substr( $bits['path'], 0, 1 ) !== '/' ) {
 861                                 $bits['path'] = '/' . $bits['path'];
 862                         }
 863                 } else {
 864                         $bits['path'] = '';
 865                 }
 866         }
 867
 868         // If the URL was protocol-relative, fix scheme and delimiter
 869         if ( $wasRelative ) {
 870                 $bits['scheme'] = '';
 871                 $bits['delimiter'] = '//';
 872         }
 873         return $bits;
 874 }
 875
 876 /**
 877  * Take a URL, make sure it's expanded to fully qualified, and replace any
 878  * encoded non-ASCII Unicode characters with their UTF-8 original forms
 879  * for more compact display and legibility for local audiences.
 880  *
 881  * @todo handle punycode domains too
 882  *
 883  * @param string $url
 884  * @return string
 885  */
 886 function wfExpandIRI( $url ) {
 887         return preg_replace_callback(
 888                 '/((?:%[89A-F][0-9A-F])+)/i',
 889                 function ( array $matches ) {
 890                         return urldecode( $matches[1] );
 891                 },
 892                 wfExpandUrl( $url )
 893         );
 894 }
 895
 896 /**
 897  * Make URL indexes, appropriate for the el_index field of externallinks.
 898  *
 899  * @param string $url
 900  * @return array
 901  */
 902 function wfMakeUrlIndexes( $url ) {
 903         $bits = wfParseUrl( $url );
 904
 905         // Reverse the labels in the hostname, convert to lower case
 906         // For emails reverse domainpart only
 907         if ( $bits['scheme'] == 'mailto' ) {
 908                 $mailparts = explode( '@', $bits['host'], 2 );
 909                 if ( count( $mailparts ) === 2 ) {
 910                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
 911                 } else {
 912                         // No domain specified, don't mangle it
 913                         $domainpart = '';
 914                 }
 915                 $reversedHost = $domainpart . '@' . $mailparts[0];
 916         } else {
 917                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
 918         }
 919         // Add an extra dot to the end
 920         // Why? Is it in wrong place in mailto links?
 921         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
 922                 $reversedHost .= '.';
 923         }
 924         // Reconstruct the pseudo-URL
 925         $prot = $bits['scheme'];
 926         $index = $prot . $bits['delimiter'] . $reversedHost;
 927         // Leave out user and password. Add the port, path, query and fragment
 928         if ( isset( $bits['port'] ) ) {
 929                 $index .= ':' . $bits['port'];
 930         }
 931         if ( isset( $bits['path'] ) ) {
 932                 $index .= $bits['path'];
 933         } else {
 934                 $index .= '/';
 935         }
 936         if ( isset( $bits['query'] ) ) {
 937                 $index .= '?' . $bits['query'];
 938         }
 939         if ( isset( $bits['fragment'] ) ) {
 940                 $index .= '#' . $bits['fragment'];
 941         }
 942
 943         if ( $prot == '' ) {
 944                 return [ "http:$index", "https:$index" ];
 945         } else {
 946                 return [ $index ];
 947         }
 948 }
 949
 950 /**
 951  * Check whether a given URL has a domain that occurs in a given set of domains
 952  * @param string $url
 953  * @param array $domains Array of domains (strings)
 954  * @return bool True if the host part of $url ends in one of the strings in $domains
 955  */
 956 function wfMatchesDomainList( $url, $domains ) {
 957         $bits = wfParseUrl( $url );
 958         if ( is_array( $bits ) && isset( $bits['host'] ) ) {
 959                 $host = '.' . $bits['host'];
 960                 foreach ( (array)$domains as $domain ) {
 961                         $domain = '.' . $domain;
 962                         if ( substr( $host, -strlen( $domain ) ) === $domain ) {
 963                                 return true;
 964                         }
 965                 }
 966         }
 967         return false;
 968 }
 969
 970 /**
 971  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
 972  * In normal operation this is a NOP.
 973  *
 974  * Controlling globals:
 975  * $wgDebugLogFile - points to the log file
 976  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
 977  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
 978  *
 979  * @since 1.25 support for additional context data
 980  *
 981  * @param string $text
 982  * @param string|bool $dest Destination of the message:
 983  *     - 'all': both to the log and HTML (debug toolbar or HTML comments)
 984  *     - 'private': excluded from HTML output
 985  *   For backward compatibility, it can also take a boolean:
 986  *     - true: same as 'all'
 987  *     - false: same as 'private'
 988  * @param array $context Additional logging context data
 989  */
 990 function wfDebug( $text, $dest = 'all', array $context = [] ) {
 991         global $wgDebugRawPage, $wgDebugLogPrefix;
 992         global $wgDebugTimestamps;
 993
 994         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
 995                 return;
 996         }
 997
 998         $text = trim( $text );
 999
1000         if ( $wgDebugTimestamps ) {
1001                 $context['seconds_elapsed'] = sprintf(
1002                         '%6.4f',
1003                         microtime( true ) - $_SERVER['REQUEST_TIME_FLOAT']
1004                 );
1005                 $context['memory_used'] = sprintf(
1006                         '%5.1fM',
1007                         ( memory_get_usage( true ) / ( 1024 * 1024 ) )
1008                 );
1009         }
1010
1011         if ( $wgDebugLogPrefix !== '' ) {
1012                 $context['prefix'] = $wgDebugLogPrefix;
1013         }
1014         $context['private'] = ( $dest === false || $dest === 'private' );
1015
1016         $logger = LoggerFactory::getInstance( 'wfDebug' );
1017         $logger->debug( $text, $context );
1018 }
1019
1020 /**
1021  * Returns true if debug logging should be suppressed if $wgDebugRawPage = false
1022  * @return bool
1023  */
1024 function wfIsDebugRawPage() {
1025         static $cache;
1026         if ( $cache !== null ) {
1027                 return $cache;
1028         }
1029         // Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
1030         // phpcs:ignore MediaWiki.Usage.SuperGlobalsUsage.SuperGlobals
1031         if ( ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' )
1032                 || (
1033                         isset( $_SERVER['SCRIPT_NAME'] )
1034                         && substr( $_SERVER['SCRIPT_NAME'], -8 ) == 'load.php'
1035                 )
1036         ) {
1037                 $cache = true;
1038         } else {
1039                 $cache = false;
1040         }
1041         return $cache;
1042 }
1043
1044 /**
1045  * Send a line giving PHP memory usage.
1046  *
1047  * @param bool $exact Print exact byte values instead of kibibytes (default: false)
1048  */
1049 function wfDebugMem( $exact = false ) {
1050         $mem = memory_get_usage();
1051         if ( !$exact ) {
1052                 $mem = floor( $mem / 1024 ) . ' KiB';
1053         } else {
1054                 $mem .= ' B';
1055         }
1056         wfDebug( "Memory usage: $mem\n" );
1057 }
1058
1059 /**
1060  * Send a line to a supplementary debug log file, if configured, or main debug
1061  * log if not.
1062  *
1063  * To configure a supplementary log file, set $wgDebugLogGroups[$logGroup] to
1064  * a string filename or an associative array mapping 'destination' to the
1065  * desired filename. The associative array may also contain a 'sample' key
1066  * with an integer value, specifying a sampling factor. Sampled log events
1067  * will be emitted with a 1 in N random chance.
1068  *
1069  * @since 1.23 support for sampling log messages via $wgDebugLogGroups.
1070  * @since 1.25 support for additional context data
1071  * @since 1.25 sample behavior dependent on configured $wgMWLoggerDefaultSpi
1072  *
1073  * @param string $logGroup
1074  * @param string $text
1075  * @param string|bool $dest Destination of the message:
1076  *     - 'all': both to the log and HTML (debug toolbar or HTML comments)
1077  *     - 'private': only to the specific log if set in $wgDebugLogGroups and
1078  *       discarded otherwise
1079  *   For backward compatibility, it can also take a boolean:
1080  *     - true: same as 'all'
1081  *     - false: same as 'private'
1082  * @param array $context Additional logging context data
1083  */
1084 function wfDebugLog(
1085         $logGroup, $text, $dest = 'all', array $context = []
1086 ) {
1087         $text = trim( $text );
1088
1089         $logger = LoggerFactory::getInstance( $logGroup );
1090         $context['private'] = ( $dest === false || $dest === 'private' );
1091         $logger->info( $text, $context );
1092 }
1093
1094 /**
1095  * Log for database errors
1096  *
1097  * @since 1.25 support for additional context data
1098  *
1099  * @param string $text Database error message.
1100  * @param array $context Additional logging context data
1101  */
1102 function wfLogDBError( $text, array $context = [] ) {
1103         $logger = LoggerFactory::getInstance( 'wfLogDBError' );
1104         $logger->error( trim( $text ), $context );
1105 }
1106
1107 /**
1108  * Throws a warning that $function is deprecated
1109  *
1110  * @param string $function
1111  * @param string|bool $version Version of MediaWiki that the function
1112  *    was deprecated in (Added in 1.19).
1113  * @param string|bool $component Added in 1.19.
1114  * @param int $callerOffset How far up the call stack is the original
1115  *    caller. 2 = function that called the function that called
1116  *    wfDeprecated (Added in 1.20)
1117  *
1118  * @return null
1119  */
1120 function wfDeprecated( $function, $version = false, $component = false, $callerOffset = 2 ) {
1121         MWDebug::deprecated( $function, $version, $component, $callerOffset + 1 );
1122 }
1123
1124 /**
1125  * Send a warning either to the debug log or in a PHP error depending on
1126  * $wgDevelopmentWarnings. To log warnings in production, use wfLogWarning() instead.
1127  *
1128  * @param string $msg Message to send
1129  * @param int $callerOffset Number of items to go back in the backtrace to
1130  *        find the correct caller (1 = function calling wfWarn, ...)
1131  * @param int $level PHP error level; defaults to E_USER_NOTICE;
1132  *        only used when $wgDevelopmentWarnings is true
1133  */
1134 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
1135         MWDebug::warning( $msg, $callerOffset + 1, $level, 'auto' );
1136 }
1137
1138 /**
1139  * Send a warning as a PHP error and the debug log. This is intended for logging
1140  * warnings in production. For logging development warnings, use WfWarn instead.
1141  *
1142  * @param string $msg Message to send
1143  * @param int $callerOffset Number of items to go back in the backtrace to
1144  *        find the correct caller (1 = function calling wfLogWarning, ...)
1145  * @param int $level PHP error level; defaults to E_USER_WARNING
1146  */
1147 function wfLogWarning( $msg, $callerOffset = 1, $level = E_USER_WARNING ) {
1148         MWDebug::warning( $msg, $callerOffset + 1, $level, 'production' );
1149 }
1150
1151 /**
1152  * Log to a file without getting "file size exceeded" signals.
1153  *
1154  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
1155  * send lines to the specified port, prefixed by the specified prefix and a space.
1156  * @since 1.25 support for additional context data
1157  *
1158  * @param string $text
1159  * @param string $file Filename
1160  * @param array $context Additional logging context data
1161  * @throws MWException
1162  * @deprecated since 1.25 Use \MediaWiki\Logger\LegacyLogger::emit or UDPTransport
1163  */
1164 function wfErrorLog( $text, $file, array $context = [] ) {
1165         wfDeprecated( __METHOD__, '1.25' );
1166         $logger = LoggerFactory::getInstance( 'wfErrorLog' );
1167         $context['destination'] = $file;
1168         $logger->info( trim( $text ), $context );
1169 }
1170
1171 /**
1172  * @todo document
1173  * @todo Move logic to MediaWiki.php
1174  */
1175 function wfLogProfilingData() {
1176         global $wgDebugLogGroups, $wgDebugRawPage;
1177
1178         $context = RequestContext::getMain();
1179         $request = $context->getRequest();
1180
1181         $profiler = Profiler::instance();
1182         $profiler->setContext( $context );
1183         $profiler->logData();
1184
1185         // Send out any buffered statsd metrics as needed
1186         MediaWiki::emitBufferedStatsdData(
1187                 MediaWikiServices::getInstance()->getStatsdDataFactory(),
1188                 $context->getConfig()
1189         );
1190
1191         // Profiling must actually be enabled...
1192         if ( $profiler instanceof ProfilerStub ) {
1193                 return;
1194         }
1195
1196         if ( isset( $wgDebugLogGroups['profileoutput'] )
1197                 && $wgDebugLogGroups['profileoutput'] === false
1198         ) {
1199                 // Explicitly disabled
1200                 return;
1201         }
1202         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
1203                 return;
1204         }
1205
1206         $ctx = [ 'elapsed' => $request->getElapsedTime() ];
1207         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
1208                 $ctx['forwarded_for'] = $_SERVER['HTTP_X_FORWARDED_FOR'];
1209         }
1210         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
1211                 $ctx['client_ip'] = $_SERVER['HTTP_CLIENT_IP'];
1212         }
1213         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
1214                 $ctx['from'] = $_SERVER['HTTP_FROM'];
1215         }
1216         if ( isset( $ctx['forwarded_for'] ) ||
1217                 isset( $ctx['client_ip'] ) ||
1218                 isset( $ctx['from'] ) ) {
1219                 $ctx['proxy'] = $_SERVER['REMOTE_ADDR'];
1220         }
1221
1222         // Don't load $wgUser at this late stage just for statistics purposes
1223         // @todo FIXME: We can detect some anons even if it is not loaded.
1224         // See User::getId()
1225         $user = $context->getUser();
1226         $ctx['anon'] = $user->isItemLoaded( 'id' ) && $user->isAnon();
1227
1228         // Command line script uses a FauxRequest object which does not have
1229         // any knowledge about an URL and throw an exception instead.
1230         try {
1231                 $ctx['url'] = urldecode( $request->getRequestURL() );
1232         } catch ( Exception $ignored ) {
1233                 // no-op
1234         }
1235
1236         $ctx['output'] = $profiler->getOutput();
1237
1238         $log = LoggerFactory::getInstance( 'profileoutput' );
1239         $log->info( "Elapsed: {elapsed}; URL: <{url}>\n{output}", $ctx );
1240 }
1241
1242 /**
1243  * Increment a statistics counter
1244  *
1245  * @param string $key
1246  * @param int $count
1247  * @return void
1248  */
1249 function wfIncrStats( $key, $count = 1 ) {
1250         $stats = MediaWikiServices::getInstance()->getStatsdDataFactory();
1251         $stats->updateCount( $key, $count );
1252 }
1253
1254 /**
1255  * Check whether the wiki is in read-only mode.
1256  *
1257  * @return bool
1258  */
1259 function wfReadOnly() {
1260         return MediaWikiServices::getInstance()->getReadOnlyMode()
1261                 ->isReadOnly();
1262 }
1263
1264 /**
1265  * Check if the site is in read-only mode and return the message if so
1266  *
1267  * This checks wfConfiguredReadOnlyReason() and the main load balancer
1268  * for replica DB lag. This may result in DB connection being made.
1269  *
1270  * @return string|bool String when in read-only mode; false otherwise
1271  */
1272 function wfReadOnlyReason() {
1273         return MediaWikiServices::getInstance()->getReadOnlyMode()
1274                 ->getReason();
1275 }
1276
1277 /**
1278  * Get the value of $wgReadOnly or the contents of $wgReadOnlyFile.
1279  *
1280  * @return string|bool String when in read-only mode; false otherwise
1281  * @since 1.27
1282  */
1283 function wfConfiguredReadOnlyReason() {
1284         return MediaWikiServices::getInstance()->getConfiguredReadOnlyMode()
1285                 ->getReason();
1286 }
1287
1288 /**
1289  * Return a Language object from $langcode
1290  *
1291  * @param Language|string|bool $langcode Either:
1292  *                  - a Language object
1293  *                  - code of the language to get the message for, if it is
1294  *                    a valid code create a language for that language, if
1295  *                    it is a string but not a valid code then make a basic
1296  *                    language object
1297  *                  - a boolean: if it's false then use the global object for
1298  *                    the current user's language (as a fallback for the old parameter
1299  *                    functionality), or if it is true then use global object
1300  *                    for the wiki's content language.
1301  * @return Language
1302  */
1303 function wfGetLangObj( $langcode = false ) {
1304         # Identify which language to get or create a language object for.
1305         # Using is_object here due to Stub objects.
1306         if ( is_object( $langcode ) ) {
1307                 # Great, we already have the object (hopefully)!
1308                 return $langcode;
1309         }
1310
1311         global $wgLanguageCode;
1312         if ( $langcode === true || $langcode === $wgLanguageCode ) {
1313                 # $langcode is the language code of the wikis content language object.
1314                 # or it is a boolean and value is true
1315                 return MediaWikiServices::getInstance()->getContentLanguage();
1316         }
1317
1318         global $wgLang;
1319         if ( $langcode === false || $langcode === $wgLang->getCode() ) {
1320                 # $langcode is the language code of user language object.
1321                 # or it was a boolean and value is false
1322                 return $wgLang;
1323         }
1324
1325         $validCodes = array_keys( Language::fetchLanguageNames() );
1326         if ( in_array( $langcode, $validCodes ) ) {
1327                 # $langcode corresponds to a valid language.
1328                 return Language::factory( $langcode );
1329         }
1330
1331         # $langcode is a string, but not a valid language code; use content language.
1332         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
1333         return MediaWikiServices::getInstance()->getContentLanguage();
1334 }
1335
1336 /**
1337  * This is the function for getting translated interface messages.
1338  *
1339  * @see Message class for documentation how to use them.
1340  * @see https://www.mediawiki.org/wiki/Manual:Messages_API
1341  *
1342  * This function replaces all old wfMsg* functions.
1343  *
1344  * @param string|string[]|MessageSpecifier $key Message key, or array of keys, or a MessageSpecifier
1345  * @param string|string[] ...$params Normal message parameters
1346  * @return Message
1347  *
1348  * @since 1.17
1349  *
1350  * @see Message::__construct
1351  */
1352 function wfMessage( $key, ...$params ) {
1353         $message = new Message( $key );
1354
1355         // We call Message::params() to reduce code duplication
1356         if ( $params ) {
1357                 $message->params( ...$params );
1358         }
1359
1360         return $message;
1361 }
1362
1363 /**
1364  * This function accepts multiple message keys and returns a message instance
1365  * for the first message which is non-empty. If all messages are empty then an
1366  * instance of the first message key is returned.
1367  *
1368  * @param string ...$keys Message keys
1369  * @return Message
1370  *
1371  * @since 1.18
1372  *
1373  * @see Message::newFallbackSequence
1374  */
1375 function wfMessageFallback( ...$keys ) {
1376         return Message::newFallbackSequence( ...$keys );
1377 }
1378
1379 /**
1380  * Replace message parameter keys on the given formatted output.
1381  *
1382  * @param string $message
1383  * @param array $args
1384  * @return string
1385  * @private
1386  */
1387 function wfMsgReplaceArgs( $message, $args ) {
1388         # Fix windows line-endings
1389         # Some messages are split with explode("\n", $msg)
1390         $message = str_replace( "\r", '', $message );
1391
1392         // Replace arguments
1393         if ( is_array( $args ) && $args ) {
1394                 if ( is_array( $args[0] ) ) {
1395                         $args = array_values( $args[0] );
1396                 }
1397                 $replacementKeys = [];
1398                 foreach ( $args as $n => $param ) {
1399                         $replacementKeys['$' . ( $n + 1 )] = $param;
1400                 }
1401                 $message = strtr( $message, $replacementKeys );
1402         }
1403
1404         return $message;
1405 }
1406
1407 /**
1408  * Fetch server name for use in error reporting etc.
1409  * Use real server name if available, so we know which machine
1410  * in a server farm generated the current page.
1411  *
1412  * @return string
1413  */
1414 function wfHostname() {
1415         static $host;
1416         if ( is_null( $host ) ) {
1417                 # Hostname overriding
1418                 global $wgOverrideHostname;
1419                 if ( $wgOverrideHostname !== false ) {
1420                         # Set static and skip any detection
1421                         $host = $wgOverrideHostname;
1422                         return $host;
1423                 }
1424
1425                 if ( function_exists( 'posix_uname' ) ) {
1426                         // This function not present on Windows
1427                         $uname = posix_uname();
1428                 } else {
1429                         $uname = false;
1430                 }
1431                 if ( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1432                         $host = $uname['nodename'];
1433                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1434                         # Windows computer name
1435                         $host = getenv( 'COMPUTERNAME' );
1436                 } else {
1437                         # This may be a virtual server.
1438                         $host = $_SERVER['SERVER_NAME'];
1439                 }
1440         }
1441         return $host;
1442 }
1443
1444 /**
1445  * Returns a script tag that stores the amount of time it took MediaWiki to
1446  * handle the request in milliseconds as 'wgBackendResponseTime'.
1447  *
1448  * If $wgShowHostnames is true, the script will also set 'wgHostname' to the
1449  * hostname of the server handling the request.
1450  *
1451  * @param string|null $nonce Value from OutputPage::getCSPNonce
1452  * @return string|WrappedString HTML
1453  */
1454 function wfReportTime( $nonce = null ) {
1455         global $wgShowHostnames;
1456
1457         $elapsed = ( microtime( true ) - $_SERVER['REQUEST_TIME_FLOAT'] );
1458         // seconds to milliseconds
1459         $responseTime = round( $elapsed * 1000 );
1460         $reportVars = [ 'wgBackendResponseTime' => $responseTime ];
1461         if ( $wgShowHostnames ) {
1462                 $reportVars['wgHostname'] = wfHostname();
1463         }
1464         return Skin::makeVariablesScript( $reportVars, $nonce );
1465 }
1466
1467 /**
1468  * Safety wrapper for debug_backtrace().
1469  *
1470  * Will return an empty array if debug_backtrace is disabled, otherwise
1471  * the output from debug_backtrace() (trimmed).
1472  *
1473  * @param int $limit This parameter can be used to limit the number of stack frames returned
1474  *
1475  * @return array Array of backtrace information
1476  */
1477 function wfDebugBacktrace( $limit = 0 ) {
1478         static $disabled = null;
1479
1480         if ( is_null( $disabled ) ) {
1481                 $disabled = !function_exists( 'debug_backtrace' );
1482                 if ( $disabled ) {
1483                         wfDebug( "debug_backtrace() is disabled\n" );
1484                 }
1485         }
1486         if ( $disabled ) {
1487                 return [];
1488         }
1489
1490         if ( $limit ) {
1491                 return array_slice( debug_backtrace( DEBUG_BACKTRACE_PROVIDE_OBJECT, $limit + 1 ), 1 );
1492         } else {
1493                 return array_slice( debug_backtrace(), 1 );
1494         }
1495 }
1496
1497 /**
1498  * Get a debug backtrace as a string
1499  *
1500  * @param bool|null $raw If true, the return value is plain text. If false, HTML.
1501  *   Defaults to $wgCommandLineMode if unset.
1502  * @return string
1503  * @since 1.25 Supports $raw parameter.
1504  */
1505 function wfBacktrace( $raw = null ) {
1506         global $wgCommandLineMode;
1507
1508         if ( $raw === null ) {
1509                 $raw = $wgCommandLineMode;
1510         }
1511
1512         if ( $raw ) {
1513                 $frameFormat = "%s line %s calls %s()\n";
1514                 $traceFormat = "%s";
1515         } else {
1516                 $frameFormat = "<li>%s line %s calls %s()</li>\n";
1517                 $traceFormat = "<ul>\n%s</ul>\n";
1518         }
1519
1520         $frames = array_map( function ( $frame ) use ( $frameFormat ) {
1521                 $file = !empty( $frame['file'] ) ? basename( $frame['file'] ) : '-';
1522                 $line = $frame['line'] ?? '-';
1523                 $call = $frame['function'];
1524                 if ( !empty( $frame['class'] ) ) {
1525                         $call = $frame['class'] . $frame['type'] . $call;
1526                 }
1527                 return sprintf( $frameFormat, $file, $line, $call );
1528         }, wfDebugBacktrace() );
1529
1530         return sprintf( $traceFormat, implode( '', $frames ) );
1531 }
1532
1533 /**
1534  * Get the name of the function which called this function
1535  * wfGetCaller( 1 ) is the function with the wfGetCaller() call (ie. __FUNCTION__)
1536  * wfGetCaller( 2 ) [default] is the caller of the function running wfGetCaller()
1537  * wfGetCaller( 3 ) is the parent of that.
1538  *
1539  * @param int $level
1540  * @return string
1541  */
1542 function wfGetCaller( $level = 2 ) {
1543         $backtrace = wfDebugBacktrace( $level + 1 );
1544         if ( isset( $backtrace[$level] ) ) {
1545                 return wfFormatStackFrame( $backtrace[$level] );
1546         } else {
1547                 return 'unknown';
1548         }
1549 }
1550
1551 /**
1552  * Return a string consisting of callers in the stack. Useful sometimes
1553  * for profiling specific points.
1554  *
1555  * @param int $limit The maximum depth of the stack frame to return, or false for the entire stack.
1556  * @return string
1557  */
1558 function wfGetAllCallers( $limit = 3 ) {
1559         $trace = array_reverse( wfDebugBacktrace() );
1560         if ( !$limit || $limit > count( $trace ) - 1 ) {
1561                 $limit = count( $trace ) - 1;
1562         }
1563         $trace = array_slice( $trace, -$limit - 1, $limit );
1564         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1565 }
1566
1567 /**
1568  * Return a string representation of frame
1569  *
1570  * @param array $frame
1571  * @return string
1572  */
1573 function wfFormatStackFrame( $frame ) {
1574         if ( !isset( $frame['function'] ) ) {
1575                 return 'NO_FUNCTION_GIVEN';
1576         }
1577         return isset( $frame['class'] ) && isset( $frame['type'] ) ?
1578                 $frame['class'] . $frame['type'] . $frame['function'] :
1579                 $frame['function'];
1580 }
1581
1582 /* Some generic result counters, pulled out of SearchEngine */
1583
1584 /**
1585  * @todo document
1586  *
1587  * @param int $offset
1588  * @param int $limit
1589  * @return string
1590  */
1591 function wfShowingResults( $offset, $limit ) {
1592         return wfMessage( 'showingresults' )->numParams( $limit, $offset + 1 )->parse();
1593 }
1594
1595 /**
1596  * Whether the client accept gzip encoding
1597  *
1598  * Uses the Accept-Encoding header to check if the client supports gzip encoding.
1599  * Use this when considering to send a gzip-encoded response to the client.
1600  *
1601  * @param bool $force Forces another check even if we already have a cached result.
1602  * @return bool
1603  */
1604 function wfClientAcceptsGzip( $force = false ) {
1605         static $result = null;
1606         if ( $result === null || $force ) {
1607                 $result = false;
1608                 if ( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1609                         # @todo FIXME: We may want to blacklist some broken browsers
1610                         $m = [];
1611                         if ( preg_match(
1612                                         '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1613                                         $_SERVER['HTTP_ACCEPT_ENCODING'],
1614                                         $m
1615                                 )
1616                         ) {
1617                                 if ( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1618                                         $result = false;
1619                                         return $result;
1620                                 }
1621                                 wfDebug( "wfClientAcceptsGzip: client accepts gzip.\n" );
1622                                 $result = true;
1623                         }
1624                 }
1625         }
1626         return $result;
1627 }
1628
1629 /**
1630  * Escapes the given text so that it may be output using addWikiText()
1631  * without any linking, formatting, etc. making its way through. This
1632  * is achieved by substituting certain characters with HTML entities.
1633  * As required by the callers, "<nowiki>" is not used.
1634  *
1635  * @param string $text Text to be escaped
1636  * @param-taint $text escapes_html
1637  * @return string
1638  */
1639 function wfEscapeWikiText( $text ) {
1640         global $wgEnableMagicLinks;
1641         static $repl = null, $repl2 = null;
1642         if ( $repl === null || defined( 'MW_PARSER_TEST' ) || defined( 'MW_PHPUNIT_TEST' ) ) {
1643                 // Tests depend upon being able to change $wgEnableMagicLinks, so don't cache
1644                 // in those situations
1645                 $repl = [
1646                         '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
1647                         '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
1648                         '{' => '&#123;', '|' => '&#124;', '}' => '&#125;', ';' => '&#59;',
1649                         "\n#" => "\n&#35;", "\r#" => "\r&#35;",
1650                         "\n*" => "\n&#42;", "\r*" => "\r&#42;",
1651                         "\n:" => "\n&#58;", "\r:" => "\r&#58;",
1652                         "\n " => "\n&#32;", "\r " => "\r&#32;",
1653                         "\n\n" => "\n&#10;", "\r\n" => "&#13;\n",
1654                         "\n\r" => "\n&#13;", "\r\r" => "\r&#13;",
1655                         "\n\t" => "\n&#9;", "\r\t" => "\r&#9;", // "\n\t\n" is treated like "\n\n"
1656                         "\n----" => "\n&#45;---", "\r----" => "\r&#45;---",
1657                         '__' => '_&#95;', '://' => '&#58;//',
1658                 ];
1659
1660                 $magicLinks = array_keys( array_filter( $wgEnableMagicLinks ) );
1661                 // We have to catch everything "\s" matches in PCRE
1662                 foreach ( $magicLinks as $magic ) {
1663                         $repl["$magic "] = "$magic&#32;";
1664                         $repl["$magic\t"] = "$magic&#9;";
1665                         $repl["$magic\r"] = "$magic&#13;";
1666                         $repl["$magic\n"] = "$magic&#10;";
1667                         $repl["$magic\f"] = "$magic&#12;";
1668                 }
1669
1670                 // And handle protocols that don't use "://"
1671                 global $wgUrlProtocols;
1672                 $repl2 = [];
1673                 foreach ( $wgUrlProtocols as $prot ) {
1674                         if ( substr( $prot, -1 ) === ':' ) {
1675                                 $repl2[] = preg_quote( substr( $prot, 0, -1 ), '/' );
1676                         }
1677                 }
1678                 $repl2 = $repl2 ? '/\b(' . implode( '|', $repl2 ) . '):/i' : '/^(?!)/';
1679         }
1680         $text = substr( strtr( "\n$text", $repl ), 1 );
1681         $text = preg_replace( $repl2, '$1&#58;', $text );
1682         return $text;
1683 }
1684
1685 /**
1686  * Sets dest to source and returns the original value of dest
1687  * If source is NULL, it just returns the value, it doesn't set the variable
1688  * If force is true, it will set the value even if source is NULL
1689  *
1690  * @param mixed &$dest
1691  * @param mixed $source
1692  * @param bool $force
1693  * @return mixed
1694  */
1695 function wfSetVar( &$dest, $source, $force = false ) {
1696         $temp = $dest;
1697         if ( !is_null( $source ) || $force ) {
1698                 $dest = $source;
1699         }
1700         return $temp;
1701 }
1702
1703 /**
1704  * As for wfSetVar except setting a bit
1705  *
1706  * @param int &$dest
1707  * @param int $bit
1708  * @param bool $state
1709  *
1710  * @return bool
1711  */
1712 function wfSetBit( &$dest, $bit, $state = true ) {
1713         $temp = (bool)( $dest & $bit );
1714         if ( !is_null( $state ) ) {
1715                 if ( $state ) {
1716                         $dest |= $bit;
1717                 } else {
1718                         $dest &= ~$bit;
1719                 }
1720         }
1721         return $temp;
1722 }
1723
1724 /**
1725  * A wrapper around the PHP function var_export().
1726  * Either print it or add it to the regular output ($wgOut).
1727  *
1728  * @param mixed $var A PHP variable to dump.
1729  */
1730 function wfVarDump( $var ) {
1731         global $wgOut;
1732         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
1733         if ( headers_sent() || !isset( $wgOut ) || !is_object( $wgOut ) ) {
1734                 print $s;
1735         } else {
1736                 $wgOut->addHTML( $s );
1737         }
1738 }
1739
1740 /**
1741  * Provide a simple HTTP error.
1742  *
1743  * @param int|string $code
1744  * @param string $label
1745  * @param string $desc
1746  */
1747 function wfHttpError( $code, $label, $desc ) {
1748         global $wgOut;
1749         HttpStatus::header( $code );
1750         if ( $wgOut ) {
1751                 $wgOut->disable();
1752                 $wgOut->sendCacheControl();
1753         }
1754
1755         MediaWiki\HeaderCallback::warnIfHeadersSent();
1756         header( 'Content-type: text/html; charset=utf-8' );
1757         print '<!DOCTYPE html>' .
1758                 '<html><head><title>' .
1759                 htmlspecialchars( $label ) .
1760                 '</title></head><body><h1>' .
1761                 htmlspecialchars( $label ) .
1762                 '</h1><p>' .
1763                 nl2br( htmlspecialchars( $desc ) ) .
1764                 "</p></body></html>\n";
1765 }
1766
1767 /**
1768  * Clear away any user-level output buffers, discarding contents.
1769  *
1770  * Suitable for 'starting afresh', for instance when streaming
1771  * relatively large amounts of data without buffering, or wanting to
1772  * output image files without ob_gzhandler's compression.
1773  *
1774  * The optional $resetGzipEncoding parameter controls suppression of
1775  * the Content-Encoding header sent by ob_gzhandler; by default it
1776  * is left. See comments for wfClearOutputBuffers() for why it would
1777  * be used.
1778  *
1779  * Note that some PHP configuration options may add output buffer
1780  * layers which cannot be removed; these are left in place.
1781  *
1782  * @param bool $resetGzipEncoding
1783  */
1784 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
1785         if ( $resetGzipEncoding ) {
1786                 // Suppress Content-Encoding and Content-Length
1787                 // headers from OutputHandler::handle.
1788                 global $wgDisableOutputCompression;
1789                 $wgDisableOutputCompression = true;
1790         }
1791         while ( $status = ob_get_status() ) {
1792                 if ( isset( $status['flags'] ) ) {
1793                         $flags = PHP_OUTPUT_HANDLER_CLEANABLE | PHP_OUTPUT_HANDLER_REMOVABLE;
1794                         $deleteable = ( $status['flags'] & $flags ) === $flags;
1795                 } elseif ( isset( $status['del'] ) ) {
1796                         $deleteable = $status['del'];
1797                 } else {
1798                         // Guess that any PHP-internal setting can't be removed.
1799                         $deleteable = $status['type'] !== 0; /* PHP_OUTPUT_HANDLER_INTERNAL */
1800                 }
1801                 if ( !$deleteable ) {
1802                         // Give up, and hope the result doesn't break
1803                         // output behavior.
1804                         break;
1805                 }
1806                 if ( $status['name'] === 'MediaWikiTestCase::wfResetOutputBuffersBarrier' ) {
1807                         // Unit testing barrier to prevent this function from breaking PHPUnit.
1808                         break;
1809                 }
1810                 if ( !ob_end_clean() ) {
1811                         // Could not remove output buffer handler; abort now
1812                         // to avoid getting in some kind of infinite loop.
1813                         break;
1814                 }
1815                 if ( $resetGzipEncoding ) {
1816                         if ( $status['name'] == 'ob_gzhandler' ) {
1817                                 // Reset the 'Content-Encoding' field set by this handler
1818                                 // so we can start fresh.
1819                                 header_remove( 'Content-Encoding' );
1820                                 break;
1821                         }
1822                 }
1823         }
1824 }
1825
1826 /**
1827  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
1828  *
1829  * Clear away output buffers, but keep the Content-Encoding header
1830  * produced by ob_gzhandler, if any.
1831  *
1832  * This should be used for HTTP 304 responses, where you need to
1833  * preserve the Content-Encoding header of the real result, but
1834  * also need to suppress the output of ob_gzhandler to keep to spec
1835  * and avoid breaking Firefox in rare cases where the headers and
1836  * body are broken over two packets.
1837  */
1838 function wfClearOutputBuffers() {
1839         wfResetOutputBuffers( false );
1840 }
1841
1842 /**
1843  * Converts an Accept-* header into an array mapping string values to quality
1844  * factors
1845  *
1846  * @param string $accept
1847  * @param string $def Default
1848  * @return float[] Associative array of string => float pairs
1849  */
1850 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
1851         # No arg means accept anything (per HTTP spec)
1852         if ( !$accept ) {
1853                 return [ $def => 1.0 ];
1854         }
1855
1856         $prefs = [];
1857
1858         $parts = explode( ',', $accept );
1859
1860         foreach ( $parts as $part ) {
1861                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
1862                 $values = explode( ';', trim( $part ) );
1863                 $match = [];
1864                 if ( count( $values ) == 1 ) {
1865                         $prefs[$values[0]] = 1.0;
1866                 } elseif ( preg_match( '/q\s*=\s*(\d*\.\d+)/', $values[1], $match ) ) {
1867                         $prefs[$values[0]] = floatval( $match[1] );
1868                 }
1869         }
1870
1871         return $prefs;
1872 }
1873
1874 /**
1875  * Checks if a given MIME type matches any of the keys in the given
1876  * array. Basic wildcards are accepted in the array keys.
1877  *
1878  * Returns the matching MIME type (or wildcard) if a match, otherwise
1879  * NULL if no match.
1880  *
1881  * @param string $type
1882  * @param array $avail
1883  * @return string
1884  * @private
1885  */
1886 function mimeTypeMatch( $type, $avail ) {
1887         if ( array_key_exists( $type, $avail ) ) {
1888                 return $type;
1889         } else {
1890                 $mainType = explode( '/', $type )[0];
1891                 if ( array_key_exists( "$mainType/*", $avail ) ) {
1892                         return "$mainType/*";
1893                 } elseif ( array_key_exists( '*/*', $avail ) ) {
1894                         return '*/*';
1895                 } else {
1896                         return null;
1897                 }
1898         }
1899 }
1900
1901 /**
1902  * Returns the 'best' match between a client's requested internet media types
1903  * and the server's list of available types. Each list should be an associative
1904  * array of type to preference (preference is a float between 0.0 and 1.0).
1905  * Wildcards in the types are acceptable.
1906  *
1907  * @param array $cprefs Client's acceptable type list
1908  * @param array $sprefs Server's offered types
1909  * @return string
1910  *
1911  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
1912  * XXX: generalize to negotiate other stuff
1913  */
1914 function wfNegotiateType( $cprefs, $sprefs ) {
1915         $combine = [];
1916
1917         foreach ( array_keys( $sprefs ) as $type ) {
1918                 $subType = explode( '/', $type )[1];
1919                 if ( $subType != '*' ) {
1920                         $ckey = mimeTypeMatch( $type, $cprefs );
1921                         if ( $ckey ) {
1922                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
1923                         }
1924                 }
1925         }
1926
1927         foreach ( array_keys( $cprefs ) as $type ) {
1928                 $subType = explode( '/', $type )[1];
1929                 if ( $subType != '*' && !array_key_exists( $type, $sprefs ) ) {
1930                         $skey = mimeTypeMatch( $type, $sprefs );
1931                         if ( $skey ) {
1932                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
1933                         }
1934                 }
1935         }
1936
1937         $bestq = 0;
1938         $besttype = null;
1939
1940         foreach ( array_keys( $combine ) as $type ) {
1941                 if ( $combine[$type] > $bestq ) {
1942                         $besttype = $type;
1943                         $bestq = $combine[$type];
1944                 }
1945         }
1946
1947         return $besttype;
1948 }
1949
1950 /**
1951  * Reference-counted warning suppression
1952  *
1953  * @deprecated since 1.26, use Wikimedia\suppressWarnings() directly
1954  * @param bool $end
1955  */
1956 function wfSuppressWarnings( $end = false ) {
1957         Wikimedia\suppressWarnings( $end );
1958 }
1959
1960 /**
1961  * @deprecated since 1.26, use Wikimedia\restoreWarnings() directly
1962  * Restore error level to previous value
1963  */
1964 function wfRestoreWarnings() {
1965         Wikimedia\restoreWarnings();
1966 }
1967
1968 /**
1969  * Get a timestamp string in one of various formats
1970  *
1971  * @param mixed $outputtype A timestamp in one of the supported formats, the
1972  *   function will autodetect which format is supplied and act accordingly.
1973  * @param mixed $ts Optional timestamp to convert, default 0 for the current time
1974  * @return string|bool String / false The same date in the format specified in $outputtype or false
1975  */
1976 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
1977         $ret = MWTimestamp::convert( $outputtype, $ts );
1978         if ( $ret === false ) {
1979                 wfDebug( "wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n" );
1980         }
1981         return $ret;
1982 }
1983
1984 /**
1985  * Return a formatted timestamp, or null if input is null.
1986  * For dealing with nullable timestamp columns in the database.
1987  *
1988  * @param int $outputtype
1989  * @param string|null $ts
1990  * @return string
1991  */
1992 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
1993         if ( is_null( $ts ) ) {
1994                 return null;
1995         } else {
1996                 return wfTimestamp( $outputtype, $ts );
1997         }
1998 }
1999
2000 /**
2001  * Convenience function; returns MediaWiki timestamp for the present time.
2002  *
2003  * @return string
2004  */
2005 function wfTimestampNow() {
2006         # return NOW
2007         return MWTimestamp::now( TS_MW );
2008 }
2009
2010 /**
2011  * Check if the operating system is Windows
2012  *
2013  * @return bool True if it's Windows, false otherwise.
2014  */
2015 function wfIsWindows() {
2016         static $isWindows = null;
2017         if ( $isWindows === null ) {
2018                 $isWindows = strtoupper( substr( PHP_OS, 0, 3 ) ) === 'WIN';
2019         }
2020         return $isWindows;
2021 }
2022
2023 /**
2024  * Check if we are running under HHVM
2025  *
2026  * @return bool
2027  */
2028 function wfIsHHVM() {
2029         return defined( 'HHVM_VERSION' );
2030 }
2031
2032 /**
2033  * Check if we are running from the commandline
2034  *
2035  * @since 1.31
2036  * @return bool
2037  */
2038 function wfIsCLI() {
2039         return PHP_SAPI === 'cli' || PHP_SAPI === 'phpdbg';
2040 }
2041
2042 /**
2043  * Tries to get the system directory for temporary files. First
2044  * $wgTmpDirectory is checked, and then the TMPDIR, TMP, and TEMP
2045  * environment variables are then checked in sequence, then
2046  * sys_get_temp_dir(), then upload_tmp_dir from php.ini.
2047  *
2048  * NOTE: When possible, use instead the tmpfile() function to create
2049  * temporary files to avoid race conditions on file creation, etc.
2050  *
2051  * @return string
2052  */
2053 function wfTempDir() {
2054         global $wgTmpDirectory;
2055
2056         if ( $wgTmpDirectory !== false ) {
2057                 return $wgTmpDirectory;
2058         }
2059
2060         return TempFSFile::getUsableTempDirectory();
2061 }
2062
2063 /**
2064  * Make directory, and make all parent directories if they don't exist
2065  *
2066  * @param string $dir Full path to directory to create
2067  * @param int|null $mode Chmod value to use, default is $wgDirectoryMode
2068  * @param string|null $caller Optional caller param for debugging.
2069  * @throws MWException
2070  * @return bool
2071  */
2072 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2073         global $wgDirectoryMode;
2074
2075         if ( FileBackend::isStoragePath( $dir ) ) { // sanity
2076                 throw new MWException( __FUNCTION__ . " given storage path '$dir'." );
2077         }
2078
2079         if ( !is_null( $caller ) ) {
2080                 wfDebug( "$caller: called wfMkdirParents($dir)\n" );
2081         }
2082
2083         if ( strval( $dir ) === '' || is_dir( $dir ) ) {
2084                 return true;
2085         }
2086
2087         $dir = str_replace( [ '\\', '/' ], DIRECTORY_SEPARATOR, $dir );
2088
2089         if ( is_null( $mode ) ) {
2090                 $mode = $wgDirectoryMode;
2091         }
2092
2093         // Turn off the normal warning, we're doing our own below
2094         Wikimedia\suppressWarnings();
2095         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2096         Wikimedia\restoreWarnings();
2097
2098         if ( !$ok ) {
2099                 // directory may have been created on another request since we last checked
2100                 if ( is_dir( $dir ) ) {
2101                         return true;
2102                 }
2103
2104                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2105                 wfLogWarning( sprintf( "failed to mkdir \"%s\" mode 0%o", $dir, $mode ) );
2106         }
2107         return $ok;
2108 }
2109
2110 /**
2111  * Remove a directory and all its content.
2112  * Does not hide error.
2113  * @param string $dir
2114  */
2115 function wfRecursiveRemoveDir( $dir ) {
2116         wfDebug( __FUNCTION__ . "( $dir )\n" );
2117         // taken from https://secure.php.net/manual/en/function.rmdir.php#98622
2118         if ( is_dir( $dir ) ) {
2119                 $objects = scandir( $dir );
2120                 foreach ( $objects as $object ) {
2121                         if ( $object != "." && $object != ".." ) {
2122                                 if ( filetype( $dir . '/' . $object ) == "dir" ) {
2123                                         wfRecursiveRemoveDir( $dir . '/' . $object );
2124                                 } else {
2125                                         unlink( $dir . '/' . $object );
2126                                 }
2127                         }
2128                 }
2129                 reset( $objects );
2130                 rmdir( $dir );
2131         }
2132 }
2133
2134 /**
2135  * @param int $nr The number to format
2136  * @param int $acc The number of digits after the decimal point, default 2
2137  * @param bool $round Whether or not to round the value, default true
2138  * @return string
2139  */
2140 function wfPercent( $nr, $acc = 2, $round = true ) {
2141         $ret = sprintf( "%.${acc}f", $nr );
2142         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2143 }
2144
2145 /**
2146  * Safety wrapper around ini_get() for boolean settings.
2147  * The values returned from ini_get() are pre-normalized for settings
2148  * set via php.ini or php_flag/php_admin_flag... but *not*
2149  * for those set via php_value/php_admin_value.
2150  *
2151  * It's fairly common for people to use php_value instead of php_flag,
2152  * which can leave you with an 'off' setting giving a false positive
2153  * for code that just takes the ini_get() return value as a boolean.
2154  *
2155  * To make things extra interesting, setting via php_value accepts
2156  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2157  * Unrecognized values go false... again opposite PHP's own coercion
2158  * from string to bool.
2159  *
2160  * Luckily, 'properly' set settings will always come back as '0' or '1',
2161  * so we only have to worry about them and the 'improper' settings.
2162  *
2163  * I frickin' hate PHP... :P
2164  *
2165  * @param string $setting
2166  * @return bool
2167  */
2168 function wfIniGetBool( $setting ) {
2169         return wfStringToBool( ini_get( $setting ) );
2170 }
2171
2172 /**
2173  * Convert string value to boolean, when the following are interpreted as true:
2174  * - on
2175  * - true
2176  * - yes
2177  * - Any number, except 0
2178  * All other strings are interpreted as false.
2179  *
2180  * @param string $val
2181  * @return bool
2182  * @since 1.31
2183  */
2184 function wfStringToBool( $val ) {
2185         $val = strtolower( $val );
2186         // 'on' and 'true' can't have whitespace around them, but '1' can.
2187         return $val == 'on'
2188                 || $val == 'true'
2189                 || $val == 'yes'
2190                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2191 }
2192
2193 /**
2194  * Version of escapeshellarg() that works better on Windows.
2195  *
2196  * Originally, this fixed the incorrect use of single quotes on Windows
2197  * (https://bugs.php.net/bug.php?id=26285) and the locale problems on Linux in
2198  * PHP 5.2.6+ (bug backported to earlier distro releases of PHP).
2199  *
2200  * @param string $args,... strings to escape and glue together,
2201  *  or a single array of strings parameter
2202  * @return string
2203  * @deprecated since 1.30 use MediaWiki\Shell::escape()
2204  */
2205 function wfEscapeShellArg( /*...*/ ) {
2206         return Shell::escape( ...func_get_args() );
2207 }
2208
2209 /**
2210  * Execute a shell command, with time and memory limits mirrored from the PHP
2211  * configuration if supported.
2212  *
2213  * @param string|string[] $cmd If string, a properly shell-escaped command line,
2214  *   or an array of unescaped arguments, in which case each value will be escaped
2215  *   Example:   [ 'convert', '-font', 'font name' ] would produce "'convert' '-font' 'font name'"
2216  * @param null|mixed &$retval Optional, will receive the program's exit code.
2217  *   (non-zero is usually failure). If there is an error from
2218  *   read, select, or proc_open(), this will be set to -1.
2219  * @param array $environ Optional environment variables which should be
2220  *   added to the executed command environment.
2221  * @param array $limits Optional array with limits(filesize, memory, time, walltime)
2222  *   this overwrites the global wgMaxShell* limits.
2223  * @param array $options Array of options:
2224  *   - duplicateStderr: Set this to true to duplicate stderr to stdout,
2225  *     including errors from limit.sh
2226  *   - profileMethod: By default this function will profile based on the calling
2227  *     method. Set this to a string for an alternative method to profile from
2228  *
2229  * @return string Collected stdout as a string
2230  * @deprecated since 1.30 use class MediaWiki\Shell\Shell
2231  */
2232 function wfShellExec( $cmd, &$retval = null, $environ = [],
2233         $limits = [], $options = []
2234 ) {
2235         if ( Shell::isDisabled() ) {
2236                 $retval = 1;
2237                 // Backwards compatibility be upon us...
2238                 return 'Unable to run external programs, proc_open() is disabled.';
2239         }
2240
2241         if ( is_array( $cmd ) ) {
2242                 $cmd = Shell::escape( $cmd );
2243         }
2244
2245         $includeStderr = isset( $options['duplicateStderr'] ) && $options['duplicateStderr'];
2246         $profileMethod = $options['profileMethod'] ?? wfGetCaller();
2247
2248         try {
2249                 $result = Shell::command( [] )
2250                         ->unsafeParams( (array)$cmd )
2251                         ->environment( $environ )
2252                         ->limits( $limits )
2253                         ->includeStderr( $includeStderr )
2254                         ->profileMethod( $profileMethod )
2255                         // For b/c
2256                         ->restrict( Shell::RESTRICT_NONE )
2257                         ->execute();
2258         } catch ( ProcOpenError $ex ) {
2259                 $retval = -1;
2260                 return '';
2261         }
2262
2263         $retval = $result->getExitCode();
2264
2265         return $result->getStdout();
2266 }
2267
2268 /**
2269  * Execute a shell command, returning both stdout and stderr. Convenience
2270  * function, as all the arguments to wfShellExec can become unwieldy.
2271  *
2272  * @note This also includes errors from limit.sh, e.g. if $wgMaxShellFileSize is exceeded.
2273  * @param string|string[] $cmd If string, a properly shell-escaped command line,
2274  *   or an array of unescaped arguments, in which case each value will be escaped
2275  *   Example:   [ 'convert', '-font', 'font name' ] would produce "'convert' '-font' 'font name'"
2276  * @param null|mixed &$retval Optional, will receive the program's exit code.
2277  *   (non-zero is usually failure)
2278  * @param array $environ Optional environment variables which should be
2279  *   added to the executed command environment.
2280  * @param array $limits Optional array with limits(filesize, memory, time, walltime)
2281  *   this overwrites the global wgMaxShell* limits.
2282  * @return string Collected stdout and stderr as a string
2283  * @deprecated since 1.30 use class MediaWiki\Shell\Shell
2284  */
2285 function wfShellExecWithStderr( $cmd, &$retval = null, $environ = [], $limits = [] ) {
2286         return wfShellExec( $cmd, $retval, $environ, $limits,
2287                 [ 'duplicateStderr' => true, 'profileMethod' => wfGetCaller() ] );
2288 }
2289
2290 /**
2291  * Generate a shell-escaped command line string to run a MediaWiki cli script.
2292  * Note that $parameters should be a flat array and an option with an argument
2293  * should consist of two consecutive items in the array (do not use "--option value").
2294  *
2295  * @deprecated since 1.31, use Shell::makeScriptCommand()
2296  *
2297  * @param string $script MediaWiki cli script path
2298  * @param array $parameters Arguments and options to the script
2299  * @param array $options Associative array of options:
2300  *     'php': The path to the php executable
2301  *     'wrapper': Path to a PHP wrapper to handle the maintenance script
2302  * @return string
2303  */
2304 function wfShellWikiCmd( $script, array $parameters = [], array $options = [] ) {
2305         global $wgPhpCli;
2306         // Give site config file a chance to run the script in a wrapper.
2307         // The caller may likely want to call wfBasename() on $script.
2308         Hooks::run( 'wfShellWikiCmd', [ &$script, &$parameters, &$options ] );
2309         $cmd = [ $options['php'] ?? $wgPhpCli ];
2310         if ( isset( $options['wrapper'] ) ) {
2311                 $cmd[] = $options['wrapper'];
2312         }
2313         $cmd[] = $script;
2314         // Escape each parameter for shell
2315         return Shell::escape( array_merge( $cmd, $parameters ) );
2316 }
2317
2318 /**
2319  * wfMerge attempts to merge differences between three texts.
2320  * Returns true for a clean merge and false for failure or a conflict.
2321  *
2322  * @param string $old
2323  * @param string $mine
2324  * @param string $yours
2325  * @param string &$result
2326  * @param string|null &$mergeAttemptResult
2327  * @return bool
2328  */
2329 function wfMerge( $old, $mine, $yours, &$result, &$mergeAttemptResult = null ) {
2330         global $wgDiff3;
2331
2332         # This check may also protect against code injection in
2333         # case of broken installations.
2334         Wikimedia\suppressWarnings();
2335         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
2336         Wikimedia\restoreWarnings();
2337
2338         if ( !$haveDiff3 ) {
2339                 wfDebug( "diff3 not found\n" );
2340                 return false;
2341         }
2342
2343         # Make temporary files
2344         $td = wfTempDir();
2345         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
2346         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
2347         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
2348
2349         # NOTE: diff3 issues a warning to stderr if any of the files does not end with
2350         #       a newline character. To avoid this, we normalize the trailing whitespace before
2351         #       creating the diff.
2352
2353         fwrite( $oldtextFile, rtrim( $old ) . "\n" );
2354         fclose( $oldtextFile );
2355         fwrite( $mytextFile, rtrim( $mine ) . "\n" );
2356         fclose( $mytextFile );
2357         fwrite( $yourtextFile, rtrim( $yours ) . "\n" );
2358         fclose( $yourtextFile );
2359
2360         # Check for a conflict
2361         $cmd = Shell::escape( $wgDiff3, '-a', '--overlap-only', $mytextName,
2362                 $oldtextName, $yourtextName );
2363         $handle = popen( $cmd, 'r' );
2364
2365         $mergeAttemptResult = '';
2366         do {
2367                 $data = fread( $handle, 8192 );
2368                 if ( strlen( $data ) == 0 ) {
2369                         break;
2370                 }
2371                 $mergeAttemptResult .= $data;
2372         } while ( true );
2373         pclose( $handle );
2374
2375         $conflict = $mergeAttemptResult !== '';
2376
2377         # Merge differences
2378         $cmd = Shell::escape( $wgDiff3, '-a', '-e', '--merge', $mytextName,
2379                 $oldtextName, $yourtextName );
2380         $handle = popen( $cmd, 'r' );
2381         $result = '';
2382         do {
2383                 $data = fread( $handle, 8192 );
2384                 if ( strlen( $data ) == 0 ) {
2385                         break;
2386                 }
2387                 $result .= $data;
2388         } while ( true );
2389         pclose( $handle );
2390         unlink( $mytextName );
2391         unlink( $oldtextName );
2392         unlink( $yourtextName );
2393
2394         if ( $result === '' && $old !== '' && !$conflict ) {
2395                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
2396                 $conflict = true;
2397         }
2398         return !$conflict;
2399 }
2400
2401 /**
2402  * Returns unified plain-text diff of two texts.
2403  * "Useful" for machine processing of diffs.
2404  *
2405  * @deprecated since 1.25, use DiffEngine/UnifiedDiffFormatter directly
2406  *
2407  * @param string $before The text before the changes.
2408  * @param string $after The text after the changes.
2409  * @param string $params Command-line options for the diff command.
2410  * @return string Unified diff of $before and $after
2411  */
2412 function wfDiff( $before, $after, $params = '-u' ) {
2413         if ( $before == $after ) {
2414                 return '';
2415         }
2416
2417         global $wgDiff;
2418         Wikimedia\suppressWarnings();
2419         $haveDiff = $wgDiff && file_exists( $wgDiff );
2420         Wikimedia\restoreWarnings();
2421
2422         # This check may also protect against code injection in
2423         # case of broken installations.
2424         if ( !$haveDiff ) {
2425                 wfDebug( "diff executable not found\n" );
2426                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
2427                 $format = new UnifiedDiffFormatter();
2428                 return $format->format( $diffs );
2429         }
2430
2431         # Make temporary files
2432         $td = wfTempDir();
2433         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
2434         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
2435
2436         fwrite( $oldtextFile, $before );
2437         fclose( $oldtextFile );
2438         fwrite( $newtextFile, $after );
2439         fclose( $newtextFile );
2440
2441         // Get the diff of the two files
2442         $cmd = "$wgDiff " . $params . ' ' . Shell::escape( $oldtextName, $newtextName );
2443
2444         $h = popen( $cmd, 'r' );
2445         if ( !$h ) {
2446                 unlink( $oldtextName );
2447                 unlink( $newtextName );
2448                 throw new Exception( __METHOD__ . '(): popen() failed' );
2449         }
2450
2451         $diff = '';
2452
2453         do {
2454                 $data = fread( $h, 8192 );
2455                 if ( strlen( $data ) == 0 ) {
2456                         break;
2457                 }
2458                 $diff .= $data;
2459         } while ( true );
2460
2461         // Clean up
2462         pclose( $h );
2463         unlink( $oldtextName );
2464         unlink( $newtextName );
2465
2466         // Kill the --- and +++ lines. They're not useful.
2467         $diff_lines = explode( "\n", $diff );
2468         if ( isset( $diff_lines[0] ) && strpos( $diff_lines[0], '---' ) === 0 ) {
2469                 unset( $diff_lines[0] );
2470         }
2471         if ( isset( $diff_lines[1] ) && strpos( $diff_lines[1], '+++' ) === 0 ) {
2472                 unset( $diff_lines[1] );
2473         }
2474
2475         $diff = implode( "\n", $diff_lines );
2476
2477         return $diff;
2478 }
2479
2480 /**
2481  * This function works like "use VERSION" in Perl, the program will die with a
2482  * backtrace if the current version of PHP is less than the version provided
2483  *
2484  * This is useful for extensions which due to their nature are not kept in sync
2485  * with releases, and might depend on other versions of PHP than the main code
2486  *
2487  * Note: PHP might die due to parsing errors in some cases before it ever
2488  *       manages to call this function, such is life
2489  *
2490  * @see perldoc -f use
2491  *
2492  * @param string|int|float $req_ver The version to check, can be a string, an integer, or a float
2493  *
2494  * @deprecated since 1.30
2495  *
2496  * @throws MWException
2497  */
2498 function wfUsePHP( $req_ver ) {
2499         wfDeprecated( __FUNCTION__, '1.30' );
2500         $php_ver = PHP_VERSION;
2501
2502         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
2503                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
2504         }
2505 }
2506
2507 /**
2508  * This function works like "use VERSION" in Perl except it checks the version
2509  * of MediaWiki, the program will die with a backtrace if the current version
2510  * of MediaWiki is less than the version provided.
2511  *
2512  * This is useful for extensions which due to their nature are not kept in sync
2513  * with releases
2514  *
2515  * Note: Due to the behavior of PHP's version_compare() which is used in this
2516  * function, if you want to allow the 'wmf' development versions add a 'c' (or
2517  * any single letter other than 'a', 'b' or 'p') as a post-fix to your
2518  * targeted version number. For example if you wanted to allow any variation
2519  * of 1.22 use `wfUseMW( '1.22c' )`. Using an 'a' or 'b' instead of 'c' will
2520  * not result in the same comparison due to the internal logic of
2521  * version_compare().
2522  *
2523  * @see perldoc -f use
2524  *
2525  * @deprecated since 1.26, use the "requires" property of extension.json
2526  * @param string|int|float $req_ver The version to check, can be a string, an integer, or a float
2527  * @throws MWException
2528  */
2529 function wfUseMW( $req_ver ) {
2530         global $wgVersion;
2531
2532         wfDeprecated( __FUNCTION__, '1.26' );
2533
2534         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
2535                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
2536         }
2537 }
2538
2539 /**
2540  * Return the final portion of a pathname.
2541  * Reimplemented because PHP5's "basename()" is buggy with multibyte text.
2542  * https://bugs.php.net/bug.php?id=33898
2543  *
2544  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
2545  * We'll consider it so always, as we don't want '\s' in our Unix paths either.
2546  *
2547  * @param string $path
2548  * @param string $suffix String to remove if present
2549  * @return string
2550  */
2551 function wfBaseName( $path, $suffix = '' ) {
2552         if ( $suffix == '' ) {
2553                 $encSuffix = '';
2554         } else {
2555                 $encSuffix = '(?:' . preg_quote( $suffix, '#' ) . ')?';
2556         }
2557
2558         $matches = [];
2559         if ( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2560                 return $matches[1];
2561         } else {
2562                 return '';
2563         }
2564 }
2565
2566 /**
2567  * Generate a relative path name to the given file.
2568  * May explode on non-matching case-insensitive paths,
2569  * funky symlinks, etc.
2570  *
2571  * @param string $path Absolute destination path including target filename
2572  * @param string $from Absolute source path, directory only
2573  * @return string
2574  */
2575 function wfRelativePath( $path, $from ) {
2576         // Normalize mixed input on Windows...
2577         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2578         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2579
2580         // Trim trailing slashes -- fix for drive root
2581         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2582         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2583
2584         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2585         $against = explode( DIRECTORY_SEPARATOR, $from );
2586
2587         if ( $pieces[0] !== $against[0] ) {
2588                 // Non-matching Windows drive letters?
2589                 // Return a full path.
2590                 return $path;
2591         }
2592
2593         // Trim off common prefix
2594         while ( count( $pieces ) && count( $against )
2595                 && $pieces[0] == $against[0] ) {
2596                 array_shift( $pieces );
2597                 array_shift( $against );
2598         }
2599
2600         // relative dots to bump us to the parent
2601         while ( count( $against ) ) {
2602                 array_unshift( $pieces, '..' );
2603                 array_shift( $against );
2604         }
2605
2606         array_push( $pieces, wfBaseName( $path ) );
2607
2608         return implode( DIRECTORY_SEPARATOR, $pieces );
2609 }
2610
2611 /**
2612  * Reset the session id
2613  *
2614  * @deprecated since 1.27, use MediaWiki\Session\SessionManager instead
2615  * @since 1.22
2616  */
2617 function wfResetSessionID() {
2618         wfDeprecated( __FUNCTION__, '1.27' );
2619         $session = SessionManager::getGlobalSession();
2620         $delay = $session->delaySave();
2621
2622         $session->resetId();
2623
2624         // Make sure a session is started, since that's what the old
2625         // wfResetSessionID() did.
2626         if ( session_id() !== $session->getId() ) {
2627                 wfSetupSession( $session->getId() );
2628         }
2629
2630         ScopedCallback::consume( $delay );
2631 }
2632
2633 /**
2634  * Initialise php session
2635  *
2636  * @deprecated since 1.27, use MediaWiki\Session\SessionManager instead.
2637  *  Generally, "using" SessionManager will be calling ->getSessionById() or
2638  *  ::getGlobalSession() (depending on whether you were passing $sessionId
2639  *  here), then calling $session->persist().
2640  * @param bool|string $sessionId
2641  */
2642 function wfSetupSession( $sessionId = false ) {
2643         wfDeprecated( __FUNCTION__, '1.27' );
2644
2645         if ( $sessionId ) {
2646                 session_id( $sessionId );
2647         }
2648
2649         $session = SessionManager::getGlobalSession();
2650         $session->persist();
2651
2652         if ( session_id() !== $session->getId() ) {
2653                 session_id( $session->getId() );
2654         }
2655         Wikimedia\quietCall( 'session_start' );
2656 }
2657
2658 /**
2659  * Get an object from the precompiled serialized directory
2660  *
2661  * @param string $name
2662  * @return mixed The variable on success, false on failure
2663  */
2664 function wfGetPrecompiledData( $name ) {
2665         global $IP;
2666
2667         $file = "$IP/serialized/$name";
2668         if ( file_exists( $file ) ) {
2669                 $blob = file_get_contents( $file );
2670                 if ( $blob ) {
2671                         return unserialize( $blob );
2672                 }
2673         }
2674         return false;
2675 }
2676
2677 /**
2678  * @since 1.32
2679  * @param string[] $data Array with string keys/values to export
2680  * @param string $header
2681  * @return string PHP code
2682  */
2683 function wfMakeStaticArrayFile( array $data, $header = 'Automatically generated' ) {
2684         $format = "\t%s => %s,\n";
2685         $code = "<?php\n"
2686                 . "// " . implode( "\n// ", explode( "\n", $header ) ) . "\n"
2687                 . "return [\n";
2688         foreach ( $data as $key => $value ) {
2689                 $code .= sprintf(
2690                         $format,
2691                         var_export( $key, true ),
2692                         var_export( $value, true )
2693                 );
2694         }
2695         $code .= "];\n";
2696         return $code;
2697 }
2698
2699 /**
2700  * Make a cache key for the local wiki.
2701  *
2702  * @deprecated since 1.30 Call makeKey on a BagOStuff instance
2703  * @param string $args,...
2704  * @return string
2705  */
2706 function wfMemcKey( /*...*/ ) {
2707         return ObjectCache::getLocalClusterInstance()->makeKey( ...func_get_args() );
2708 }
2709
2710 /**
2711  * Make a cache key for a foreign DB.
2712  *
2713  * Must match what wfMemcKey() would produce in context of the foreign wiki.
2714  *
2715  * @param string $db
2716  * @param string $prefix
2717  * @param string $args,...
2718  * @return string
2719  */
2720 function wfForeignMemcKey( $db, $prefix /*...*/ ) {
2721         $args = array_slice( func_get_args(), 2 );
2722         $keyspace = $prefix ? "$db-$prefix" : $db;
2723         return ObjectCache::getLocalClusterInstance()->makeKeyInternal( $keyspace, $args );
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 ObjectCache::getLocalClusterInstance()->makeGlobalKey( ...func_get_args() );
2740 }
2741
2742 /**
2743  * Get an ASCII string identifying this wiki
2744  * This is used as a prefix in memcached keys
2745  *
2746  * @return string
2747  */
2748 function wfWikiID() {
2749         global $wgDBprefix, $wgDBname;
2750         if ( $wgDBprefix ) {
2751                 return "$wgDBname-$wgDBprefix";
2752         } else {
2753                 return $wgDBname;
2754         }
2755 }
2756
2757 /**
2758  * Split a wiki ID into DB name and table prefix
2759  *
2760  * @param string $wiki
2761  *
2762  * @return array
2763  */
2764 function wfSplitWikiID( $wiki ) {
2765         $bits = explode( '-', $wiki, 2 );
2766         if ( count( $bits ) < 2 ) {
2767                 $bits[] = '';
2768         }
2769         return $bits;
2770 }
2771
2772 /**
2773  * Get a Database object.
2774  *
2775  * @param int $db Index of the connection to get. May be DB_MASTER for the
2776  *            master (for write queries), DB_REPLICA for potentially lagged read
2777  *            queries, or an integer >= 0 for a particular server.
2778  *
2779  * @param string|string[] $groups Query groups. An array of group names that this query
2780  *                belongs to. May contain a single string if the query is only
2781  *                in one group.
2782  *
2783  * @param string|bool $wiki The wiki ID, or false for the current wiki
2784  *
2785  * Note: multiple calls to wfGetDB(DB_REPLICA) during the course of one request
2786  * will always return the same object, unless the underlying connection or load
2787  * balancer is manually destroyed.
2788  *
2789  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
2790  * updater to ensure that a proper database is being updated.
2791  *
2792  * @todo Replace calls to wfGetDB with calls to LoadBalancer::getConnection()
2793  *       on an injected instance of LoadBalancer.
2794  *
2795  * @return \Wikimedia\Rdbms\Database
2796  */
2797 function wfGetDB( $db, $groups = [], $wiki = false ) {
2798         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
2799 }
2800
2801 /**
2802  * Get a load balancer object.
2803  *
2804  * @deprecated since 1.27, use MediaWikiServices::getDBLoadBalancer()
2805  *              or MediaWikiServices::getDBLoadBalancerFactory() instead.
2806  *
2807  * @param string|bool $wiki Wiki ID, or false for the current wiki
2808  * @return \Wikimedia\Rdbms\LoadBalancer
2809  */
2810 function wfGetLB( $wiki = false ) {
2811         if ( $wiki === false ) {
2812                 return MediaWikiServices::getInstance()->getDBLoadBalancer();
2813         } else {
2814                 $factory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
2815                 return $factory->getMainLB( $wiki );
2816         }
2817 }
2818
2819 /**
2820  * Get the load balancer factory object
2821  *
2822  * @deprecated since 1.27, use MediaWikiServices::getDBLoadBalancerFactory() instead.
2823  *
2824  * @return \Wikimedia\Rdbms\LBFactory
2825  */
2826 function wfGetLBFactory() {
2827         return MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
2828 }
2829
2830 /**
2831  * Find a file.
2832  * Shortcut for RepoGroup::singleton()->findFile()
2833  *
2834  * @param string|Title $title String or Title object
2835  * @param array $options Associative array of options (see RepoGroup::findFile)
2836  * @return File|bool File, or false if the file does not exist
2837  */
2838 function wfFindFile( $title, $options = [] ) {
2839         return RepoGroup::singleton()->findFile( $title, $options );
2840 }
2841
2842 /**
2843  * Get an object referring to a locally registered file.
2844  * Returns a valid placeholder object if the file does not exist.
2845  *
2846  * @param Title|string $title
2847  * @return LocalFile|null A File, or null if passed an invalid Title
2848  */
2849 function wfLocalFile( $title ) {
2850         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
2851 }
2852
2853 /**
2854  * Should low-performance queries be disabled?
2855  *
2856  * @return bool
2857  * @codeCoverageIgnore
2858  */
2859 function wfQueriesMustScale() {
2860         global $wgMiserMode;
2861         return $wgMiserMode
2862                 || ( SiteStats::pages() > 100000
2863                 && SiteStats::edits() > 1000000
2864                 && SiteStats::users() > 10000 );
2865 }
2866
2867 /**
2868  * Get the path to a specified script file, respecting file
2869  * extensions; this is a wrapper around $wgScriptPath etc.
2870  * except for 'index' and 'load' which use $wgScript/$wgLoadScript
2871  *
2872  * @param string $script Script filename, sans extension
2873  * @return string
2874  */
2875 function wfScript( $script = 'index' ) {
2876         global $wgScriptPath, $wgScript, $wgLoadScript;
2877         if ( $script === 'index' ) {
2878                 return $wgScript;
2879         } elseif ( $script === 'load' ) {
2880                 return $wgLoadScript;
2881         } else {
2882                 return "{$wgScriptPath}/{$script}.php";
2883         }
2884 }
2885
2886 /**
2887  * Get the script URL.
2888  *
2889  * @return string Script URL
2890  */
2891 function wfGetScriptUrl() {
2892         if ( isset( $_SERVER['SCRIPT_NAME'] ) ) {
2893                 /* as it was called, minus the query string.
2894                  *
2895                  * Some sites use Apache rewrite rules to handle subdomains,
2896                  * and have PHP set up in a weird way that causes PHP_SELF
2897                  * to contain the rewritten URL instead of the one that the
2898                  * outside world sees.
2899                  *
2900                  * If in this mode, use SCRIPT_URL instead, which mod_rewrite
2901                  * provides containing the "before" URL.
2902                  */
2903                 return $_SERVER['SCRIPT_NAME'];
2904         } else {
2905                 return $_SERVER['URL'];
2906         }
2907 }
2908
2909 /**
2910  * Convenience function converts boolean values into "true"
2911  * or "false" (string) values
2912  *
2913  * @param bool $value
2914  * @return string
2915  */
2916 function wfBoolToStr( $value ) {
2917         return $value ? 'true' : 'false';
2918 }
2919
2920 /**
2921  * Get a platform-independent path to the null file, e.g. /dev/null
2922  *
2923  * @return string
2924  */
2925 function wfGetNull() {
2926         return wfIsWindows() ? 'NUL' : '/dev/null';
2927 }
2928
2929 /**
2930  * Waits for the replica DBs to catch up to the master position
2931  *
2932  * Use this when updating very large numbers of rows, as in maintenance scripts,
2933  * to avoid causing too much lag. Of course, this is a no-op if there are no replica DBs.
2934  *
2935  * By default this waits on the main DB cluster of the current wiki.
2936  * If $cluster is set to "*" it will wait on all DB clusters, including
2937  * external ones. If the lag being waiting on is caused by the code that
2938  * does this check, it makes since to use $ifWritesSince, particularly if
2939  * cluster is "*", to avoid excess overhead.
2940  *
2941  * Never call this function after a big DB write that is still in a transaction.
2942  * This only makes sense after the possible lag inducing changes were committed.
2943  *
2944  * @param float|null $ifWritesSince Only wait if writes were done since this UNIX timestamp
2945  * @param string|bool $wiki Wiki identifier accepted by wfGetLB
2946  * @param string|bool $cluster Cluster name accepted by LBFactory. Default: false.
2947  * @param int|null $timeout Max wait time. Default: 1 day (cli), ~10 seconds (web)
2948  * @return bool Success (able to connect and no timeouts reached)
2949  * @deprecated since 1.27 Use LBFactory::waitForReplication
2950  */
2951 function wfWaitForSlaves(
2952         $ifWritesSince = null, $wiki = false, $cluster = false, $timeout = null
2953 ) {
2954         if ( $timeout === null ) {
2955                 $timeout = wfIsCLI() ? 60 : 10;
2956         }
2957
2958         if ( $cluster === '*' ) {
2959                 $cluster = false;
2960                 $wiki = false;
2961         } elseif ( $wiki === false ) {
2962                 $wiki = wfWikiID();
2963         }
2964
2965         try {
2966                 $lbFactory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
2967                 $lbFactory->waitForReplication( [
2968                         'wiki' => $wiki,
2969                         'cluster' => $cluster,
2970                         'timeout' => $timeout,
2971                         // B/C: first argument used to be "max seconds of lag"; ignore such values
2972                         'ifWritesSince' => ( $ifWritesSince > 1e9 ) ? $ifWritesSince : null
2973                 ] );
2974         } catch ( DBReplicationWaitError $e ) {
2975                 return false;
2976         }
2977
2978         return true;
2979 }
2980
2981 /**
2982  * Count down from $seconds to zero on the terminal, with a one-second pause
2983  * between showing each number. For use in command-line scripts.
2984  *
2985  * @deprecated since 1.31, use Maintenance::countDown()
2986  *
2987  * @codeCoverageIgnore
2988  * @param int $seconds
2989  */
2990 function wfCountDown( $seconds ) {
2991         wfDeprecated( __FUNCTION__, '1.31' );
2992         for ( $i = $seconds; $i >= 0; $i-- ) {
2993                 if ( $i != $seconds ) {
2994                         echo str_repeat( "\x08", strlen( $i + 1 ) );
2995                 }
2996                 echo $i;
2997                 flush();
2998                 if ( $i ) {
2999                         sleep( 1 );
3000                 }
3001         }
3002         echo "\n";
3003 }
3004
3005 /**
3006  * Replace all invalid characters with '-'.
3007  * Additional characters can be defined in $wgIllegalFileChars (see T22489).
3008  * By default, $wgIllegalFileChars includes ':', '/', '\'.
3009  *
3010  * @param string $name Filename to process
3011  * @return string
3012  */
3013 function wfStripIllegalFilenameChars( $name ) {
3014         global $wgIllegalFileChars;
3015         $illegalFileChars = $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '';
3016         $name = preg_replace(
3017                 "/[^" . Title::legalChars() . "]" . $illegalFileChars . "/",
3018                 '-',
3019                 $name
3020         );
3021         // $wgIllegalFileChars may not include '/' and '\', so we still need to do this
3022         $name = wfBaseName( $name );
3023         return $name;
3024 }
3025
3026 /**
3027  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit
3028  *
3029  * @return int Resulting value of the memory limit.
3030  */
3031 function wfMemoryLimit() {
3032         global $wgMemoryLimit;
3033         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3034         if ( $memlimit != -1 ) {
3035                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3036                 if ( $conflimit == -1 ) {
3037                         wfDebug( "Removing PHP's memory limit\n" );
3038                         Wikimedia\suppressWarnings();
3039                         ini_set( 'memory_limit', $conflimit );
3040                         Wikimedia\restoreWarnings();
3041                         return $conflimit;
3042                 } elseif ( $conflimit > $memlimit ) {
3043                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3044                         Wikimedia\suppressWarnings();
3045                         ini_set( 'memory_limit', $conflimit );
3046                         Wikimedia\restoreWarnings();
3047                         return $conflimit;
3048                 }
3049         }
3050         return $memlimit;
3051 }
3052
3053 /**
3054  * Set PHP's time limit to the larger of php.ini or $wgTransactionalTimeLimit
3055  *
3056  * @return int Prior time limit
3057  * @since 1.26
3058  */
3059 function wfTransactionalTimeLimit() {
3060         global $wgTransactionalTimeLimit;
3061
3062         $timeLimit = ini_get( 'max_execution_time' );
3063         // Note that CLI scripts use 0
3064         if ( $timeLimit > 0 && $wgTransactionalTimeLimit > $timeLimit ) {
3065                 set_time_limit( $wgTransactionalTimeLimit );
3066         }
3067
3068         ignore_user_abort( true ); // ignore client disconnects
3069
3070         return $timeLimit;
3071 }
3072
3073 /**
3074  * Converts shorthand byte notation to integer form
3075  *
3076  * @param string $string
3077  * @param int $default Returned if $string is empty
3078  * @return int
3079  */
3080 function wfShorthandToInteger( $string = '', $default = -1 ) {
3081         $string = trim( $string );
3082         if ( $string === '' ) {
3083                 return $default;
3084         }
3085         $last = $string[strlen( $string ) - 1];
3086         $val = intval( $string );
3087         switch ( $last ) {
3088                 case 'g':
3089                 case 'G':
3090                         $val *= 1024;
3091                         // break intentionally missing
3092                 case 'm':
3093                 case 'M':
3094                         $val *= 1024;
3095                         // break intentionally missing
3096                 case 'k':
3097                 case 'K':
3098                         $val *= 1024;
3099         }
3100
3101         return $val;
3102 }
3103
3104 /**
3105  * Get the normalised IETF language tag
3106  * See unit test for examples.
3107  * See mediawiki.language.bcp47 for the JavaScript implementation.
3108  *
3109  * @deprecated since 1.31, use LanguageCode::bcp47() directly.
3110  *
3111  * @param string $code The language code.
3112  * @return string The language code which complying with BCP 47 standards.
3113  */
3114 function wfBCP47( $code ) {
3115         wfDeprecated( __METHOD__, '1.31' );
3116         return LanguageCode::bcp47( $code );
3117 }
3118
3119 /**
3120  * Get a specific cache object.
3121  *
3122  * @deprecated since 1.32, use ObjectCache::getInstance() instead
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  * @deprecated since 1.32, use ObjectCache::getLocalClusterInstance() instead
3134  * @return BagOStuff
3135  */
3136 function wfGetMainCache() {
3137         return ObjectCache::getLocalClusterInstance();
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  * Call hook functions defined in $wgHooks
3152  *
3153  * @param string $event Event name
3154  * @param array $args Parameters passed to hook functions
3155  * @param string|null $deprecatedVersion Optionally mark hook as deprecated with version number
3156  *
3157  * @return bool True if no handler aborted the hook
3158  * @deprecated since 1.25 - use Hooks::run
3159  */
3160 function wfRunHooks( $event, array $args = [], $deprecatedVersion = null ) {
3161         wfDeprecated( __METHOD__, '1.25' );
3162         return Hooks::run( $event, $args, $deprecatedVersion );
3163 }
3164
3165 /**
3166  * Wrapper around php's unpack.
3167  *
3168  * @param string $format The format string (See php's docs)
3169  * @param string $data A binary string of binary data
3170  * @param int|bool $length The minimum length of $data or false. This is to
3171  *      prevent reading beyond the end of $data. false to disable the check.
3172  *
3173  * Also be careful when using this function to read unsigned 32 bit integer
3174  * because php might make it negative.
3175  *
3176  * @throws MWException If $data not long enough, or if unpack fails
3177  * @return array Associative array of the extracted data
3178  */
3179 function wfUnpack( $format, $data, $length = false ) {
3180         if ( $length !== false ) {
3181                 $realLen = strlen( $data );
3182                 if ( $realLen < $length ) {
3183                         throw new MWException( "Tried to use wfUnpack on a "
3184                                 . "string of length $realLen, but needed one "
3185                                 . "of at least length $length."
3186                         );
3187                 }
3188         }
3189
3190         Wikimedia\suppressWarnings();
3191         $result = unpack( $format, $data );
3192         Wikimedia\restoreWarnings();
3193
3194         if ( $result === false ) {
3195                 // If it cannot extract the packed data.
3196                 throw new MWException( "unpack could not unpack binary data" );
3197         }
3198         return $result;
3199 }
3200
3201 /**
3202  * Determine if an image exists on the 'bad image list'.
3203  *
3204  * The format of MediaWiki:Bad_image_list is as follows:
3205  *    * Only list items (lines starting with "*") are considered
3206  *    * The first link on a line must be a link to a bad image
3207  *    * Any subsequent links on the same line are considered to be exceptions,
3208  *      i.e. articles where the image may occur inline.
3209  *
3210  * @param string $name The image name to check
3211  * @param Title|bool $contextTitle The page on which the image occurs, if known
3212  * @param string|null $blacklist Wikitext of a file blacklist
3213  * @return bool
3214  */
3215 function wfIsBadImage( $name, $contextTitle = false, $blacklist = null ) {
3216         # Handle redirects; callers almost always hit wfFindFile() anyway,
3217         # so just use that method because it has a fast process cache.
3218         $file = wfFindFile( $name ); // get the final name
3219         $name = $file ? $file->getTitle()->getDBkey() : $name;
3220
3221         # Run the extension hook
3222         $bad = false;
3223         if ( !Hooks::run( 'BadImage', [ $name, &$bad ] ) ) {
3224                 return (bool)$bad;
3225         }
3226
3227         $cache = ObjectCache::getLocalServerInstance( 'hash' );
3228         $key = $cache->makeKey(
3229                 'bad-image-list', ( $blacklist === null ) ? 'default' : md5( $blacklist )
3230         );
3231         $badImages = $cache->get( $key );
3232
3233         if ( $badImages === false ) { // cache miss
3234                 if ( $blacklist === null ) {
3235                         $blacklist = wfMessage( 'bad_image_list' )->inContentLanguage()->plain(); // site list
3236                 }
3237                 # Build the list now
3238                 $badImages = [];
3239                 $lines = explode( "\n", $blacklist );
3240                 foreach ( $lines as $line ) {
3241                         # List items only
3242                         if ( substr( $line, 0, 1 ) !== '*' ) {
3243                                 continue;
3244                         }
3245
3246                         # Find all links
3247                         $m = [];
3248                         if ( !preg_match_all( '/\[\[:?(.*?)\]\]/', $line, $m ) ) {
3249                                 continue;
3250                         }
3251
3252                         $exceptions = [];
3253                         $imageDBkey = false;
3254                         foreach ( $m[1] as $i => $titleText ) {
3255                                 $title = Title::newFromText( $titleText );
3256                                 if ( !is_null( $title ) ) {
3257                                         if ( $i == 0 ) {
3258                                                 $imageDBkey = $title->getDBkey();
3259                                         } else {
3260                                                 $exceptions[$title->getPrefixedDBkey()] = true;
3261                                         }
3262                                 }
3263                         }
3264
3265                         if ( $imageDBkey !== false ) {
3266                                 $badImages[$imageDBkey] = $exceptions;
3267                         }
3268                 }
3269                 $cache->set( $key, $badImages, 60 );
3270         }
3271
3272         $contextKey = $contextTitle ? $contextTitle->getPrefixedDBkey() : false;
3273         $bad = isset( $badImages[$name] ) && !isset( $badImages[$name][$contextKey] );
3274
3275         return $bad;
3276 }
3277
3278 /**
3279  * Determine whether the client at a given source IP is likely to be able to
3280  * access the wiki via HTTPS.
3281  *
3282  * @param string $ip The IPv4/6 address in the normal human-readable form
3283  * @return bool
3284  */
3285 function wfCanIPUseHTTPS( $ip ) {
3286         $canDo = true;
3287         Hooks::run( 'CanIPUseHTTPS', [ $ip, &$canDo ] );
3288         return !!$canDo;
3289 }
3290
3291 /**
3292  * Determine input string is represents as infinity
3293  *
3294  * @param string $str The string to determine
3295  * @return bool
3296  * @since 1.25
3297  */
3298 function wfIsInfinity( $str ) {
3299         // These are hardcoded elsewhere in MediaWiki (e.g. mediawiki.special.block.js).
3300         $infinityValues = [ 'infinite', 'indefinite', 'infinity', 'never' ];
3301         return in_array( $str, $infinityValues );
3302 }
3303
3304 /**
3305  * Returns true if these thumbnail parameters match one that MediaWiki
3306  * requests from file description pages and/or parser output.
3307  *
3308  * $params is considered non-standard if they involve a non-standard
3309  * width or any non-default parameters aside from width and page number.
3310  * The number of possible files with standard parameters is far less than
3311  * that of all combinations; rate-limiting for them can thus be more generious.
3312  *
3313  * @param File $file
3314  * @param array $params
3315  * @return bool
3316  * @since 1.24 Moved from thumb.php to GlobalFunctions in 1.25
3317  */
3318 function wfThumbIsStandard( File $file, array $params ) {
3319         global $wgThumbLimits, $wgImageLimits, $wgResponsiveImages;
3320
3321         $multipliers = [ 1 ];
3322         if ( $wgResponsiveImages ) {
3323                 // These available sizes are hardcoded currently elsewhere in MediaWiki.
3324                 // @see Linker::processResponsiveImages
3325                 $multipliers[] = 1.5;
3326                 $multipliers[] = 2;
3327         }
3328
3329         $handler = $file->getHandler();
3330         if ( !$handler || !isset( $params['width'] ) ) {
3331                 return false;
3332         }
3333
3334         $basicParams = [];
3335         if ( isset( $params['page'] ) ) {
3336                 $basicParams['page'] = $params['page'];
3337         }
3338
3339         $thumbLimits = [];
3340         $imageLimits = [];
3341         // Expand limits to account for multipliers
3342         foreach ( $multipliers as $multiplier ) {
3343                 $thumbLimits = array_merge( $thumbLimits, array_map(
3344                         function ( $width ) use ( $multiplier ) {
3345                                 return round( $width * $multiplier );
3346                         }, $wgThumbLimits )
3347                 );
3348                 $imageLimits = array_merge( $imageLimits, array_map(
3349                         function ( $pair ) use ( $multiplier ) {
3350                                 return [
3351                                         round( $pair[0] * $multiplier ),
3352                                         round( $pair[1] * $multiplier ),
3353                                 ];
3354                         }, $wgImageLimits )
3355                 );
3356         }
3357
3358         // Check if the width matches one of $wgThumbLimits
3359         if ( in_array( $params['width'], $thumbLimits ) ) {
3360                 $normalParams = $basicParams + [ 'width' => $params['width'] ];
3361                 // Append any default values to the map (e.g. "lossy", "lossless", ...)
3362                 $handler->normaliseParams( $file, $normalParams );
3363         } else {
3364                 // If not, then check if the width matchs one of $wgImageLimits
3365                 $match = false;
3366                 foreach ( $imageLimits as $pair ) {
3367                         $normalParams = $basicParams + [ 'width' => $pair[0], 'height' => $pair[1] ];
3368                         // Decide whether the thumbnail should be scaled on width or height.
3369                         // Also append any default values to the map (e.g. "lossy", "lossless", ...)
3370                         $handler->normaliseParams( $file, $normalParams );
3371                         // Check if this standard thumbnail size maps to the given width
3372                         if ( $normalParams['width'] == $params['width'] ) {
3373                                 $match = true;
3374                                 break;
3375                         }
3376                 }
3377                 if ( !$match ) {
3378                         return false; // not standard for description pages
3379                 }
3380         }
3381
3382         // Check that the given values for non-page, non-width, params are just defaults
3383         foreach ( $params as $key => $value ) {
3384                 if ( !isset( $normalParams[$key] ) || $normalParams[$key] != $value ) {
3385                         return false;
3386                 }
3387         }
3388
3389         return true;
3390 }
3391
3392 /**
3393  * Merges two (possibly) 2 dimensional arrays into the target array ($baseArray).
3394  *
3395  * Values that exist in both values will be combined with += (all values of the array
3396  * of $newValues will be added to the values of the array of $baseArray, while values,
3397  * that exists in both, the value of $baseArray will be used).
3398  *
3399  * @param array $baseArray The array where you want to add the values of $newValues to
3400  * @param array $newValues An array with new values
3401  * @return array The combined array
3402  * @since 1.26
3403  */
3404 function wfArrayPlus2d( array $baseArray, array $newValues ) {
3405         // First merge items that are in both arrays
3406         foreach ( $baseArray as $name => &$groupVal ) {
3407                 if ( isset( $newValues[$name] ) ) {
3408                         $groupVal += $newValues[$name];
3409                 }
3410         }
3411         // Now add items that didn't exist yet
3412         $baseArray += $newValues;
3413
3414         return $baseArray;
3415 }
3416
3417 /**
3418  * Get system resource usage of current request context.
3419  * Invokes the getrusage(2) system call, requesting RUSAGE_SELF if on PHP5
3420  * or RUSAGE_THREAD if on HHVM. Returns false if getrusage is not available.
3421  *
3422  * @since 1.24
3423  * @return array|bool Resource usage data or false if no data available.
3424  */
3425 function wfGetRusage() {
3426         if ( !function_exists( 'getrusage' ) ) {
3427                 return false;
3428         } elseif ( defined( 'HHVM_VERSION' ) && PHP_OS === 'Linux' ) {
3429                 return getrusage( 2 /* RUSAGE_THREAD */ );
3430         } else {
3431                 return getrusage( 0 /* RUSAGE_SELF */ );
3432         }
3433 }