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\StaticArrayWriter;
  34 use Wikimedia\Rdbms\DBReplicationWaitError;
  35 use Wikimedia\WrappedString;
  36
  37 /**
  38  * Load an extension
  39  *
  40  * This queues an extension to be loaded through
  41  * the ExtensionRegistry system.
  42  *
  43  * @param string $ext Name of the extension to load
  44  * @param string|null $path Absolute path of where to find the extension.json file
  45  * @since 1.25
  46  */
  47 function wfLoadExtension( $ext, $path = null ) {
  48         if ( !$path ) {
  49                 global $wgExtensionDirectory;
  50                 $path = "$wgExtensionDirectory/$ext/extension.json";
  51         }
  52         ExtensionRegistry::getInstance()->queue( $path );
  53 }
  54
  55 /**
  56  * Load multiple extensions at once
  57  *
  58  * Same as wfLoadExtension, but more efficient if you
  59  * are loading multiple extensions.
  60  *
  61  * If you want to specify custom paths, you should interact with
  62  * ExtensionRegistry directly.
  63  *
  64  * @see wfLoadExtension
  65  * @param string[] $exts Array of extension names to load
  66  * @since 1.25
  67  */
  68 function wfLoadExtensions( array $exts ) {
  69         global $wgExtensionDirectory;
  70         $registry = ExtensionRegistry::getInstance();
  71         foreach ( $exts as $ext ) {
  72                 $registry->queue( "$wgExtensionDirectory/$ext/extension.json" );
  73         }
  74 }
  75
  76 /**
  77  * Load a skin
  78  *
  79  * @see wfLoadExtension
  80  * @param string $skin Name of the extension to load
  81  * @param string|null $path Absolute path of where to find the skin.json file
  82  * @since 1.25
  83  */
  84 function wfLoadSkin( $skin, $path = null ) {
  85         if ( !$path ) {
  86                 global $wgStyleDirectory;
  87                 $path = "$wgStyleDirectory/$skin/skin.json";
  88         }
  89         ExtensionRegistry::getInstance()->queue( $path );
  90 }
  91
  92 /**
  93  * Load multiple skins at once
  94  *
  95  * @see wfLoadExtensions
  96  * @param string[] $skins Array of extension names to load
  97  * @since 1.25
  98  */
  99 function wfLoadSkins( array $skins ) {
 100         global $wgStyleDirectory;
 101         $registry = ExtensionRegistry::getInstance();
 102         foreach ( $skins as $skin ) {
 103                 $registry->queue( "$wgStyleDirectory/$skin/skin.json" );
 104         }
 105 }
 106
 107 /**
 108  * Like array_diff( $a, $b ) except that it works with two-dimensional arrays.
 109  * @param array $a
 110  * @param array $b
 111  * @return array
 112  */
 113 function wfArrayDiff2( $a, $b ) {
 114         return array_udiff( $a, $b, 'wfArrayDiff2_cmp' );
 115 }
 116
 117 /**
 118  * @param array|string $a
 119  * @param array|string $b
 120  * @return int
 121  */
 122 function wfArrayDiff2_cmp( $a, $b ) {
 123         if ( is_string( $a ) && is_string( $b ) ) {
 124                 return strcmp( $a, $b );
 125         } elseif ( count( $a ) !== count( $b ) ) {
 126                 return count( $a ) <=> count( $b );
 127         } else {
 128                 reset( $a );
 129                 reset( $b );
 130                 while ( key( $a ) !== null && key( $b ) !== null ) {
 131                         $valueA = current( $a );
 132                         $valueB = current( $b );
 133                         $cmp = strcmp( $valueA, $valueB );
 134                         if ( $cmp !== 0 ) {
 135                                 return $cmp;
 136                         }
 137                         next( $a );
 138                         next( $b );
 139                 }
 140                 return 0;
 141         }
 142 }
 143
 144 /**
 145  * @deprecated since 1.32, use array_filter() with ARRAY_FILTER_USE_BOTH directly
 146  *
 147  * @param array $arr
 148  * @param callable $callback Will be called with the array value and key (in that order) and
 149  *   should return a bool which will determine whether the array element is kept.
 150  * @return array
 151  */
 152 function wfArrayFilter( array $arr, callable $callback ) {
 153         return array_filter( $arr, $callback, ARRAY_FILTER_USE_BOTH );
 154 }
 155
 156 /**
 157  * @deprecated since 1.32, use array_filter() with ARRAY_FILTER_USE_KEY directly
 158  *
 159  * @param array $arr
 160  * @param callable $callback Will be called with the array key and should return a bool which
 161  *   will determine whether the array element is kept.
 162  * @return array
 163  */
 164 function wfArrayFilterByKey( array $arr, callable $callback ) {
 165         return array_filter( $arr, $callback, ARRAY_FILTER_USE_KEY );
 166 }
 167
 168 /**
 169  * Appends to second array if $value differs from that in $default
 170  *
 171  * @param string|int $key
 172  * @param mixed $value
 173  * @param mixed $default
 174  * @param array &$changed Array to alter
 175  * @throws MWException
 176  */
 177 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
 178         if ( is_null( $changed ) ) {
 179                 throw new MWException( 'GlobalFunctions::wfAppendToArrayIfNotDefault got null' );
 180         }
 181         if ( $default[$key] !== $value ) {
 182                 $changed[$key] = $value;
 183         }
 184 }
 185
 186 /**
 187  * Merge arrays in the style of getUserPermissionsErrors, with duplicate removal
 188  * e.g.
 189  *     wfMergeErrorArrays(
 190  *       [ [ 'x' ] ],
 191  *       [ [ 'x', '2' ] ],
 192  *       [ [ 'x' ] ],
 193  *       [ [ 'y' ] ]
 194  *     );
 195  * returns:
 196  *     [
 197  *       [ 'x', '2' ],
 198  *       [ 'x' ],
 199  *       [ 'y' ]
 200  *     ]
 201  *
 202  * @param array $array1,...
 203  * @return array
 204  */
 205 function wfMergeErrorArrays( /*...*/ ) {
 206         $args = func_get_args();
 207         $out = [];
 208         foreach ( $args as $errors ) {
 209                 foreach ( $errors as $params ) {
 210                         $originalParams = $params;
 211                         if ( $params[0] instanceof MessageSpecifier ) {
 212                                 $msg = $params[0];
 213                                 $params = array_merge( [ $msg->getKey() ], $msg->getParams() );
 214                         }
 215                         # @todo FIXME: Sometimes get nested arrays for $params,
 216                         # which leads to E_NOTICEs
 217                         $spec = implode( "\t", $params );
 218                         $out[$spec] = $originalParams;
 219                 }
 220         }
 221         return array_values( $out );
 222 }
 223
 224 /**
 225  * Insert array into another array after the specified *KEY*
 226  *
 227  * @param array $array The array.
 228  * @param array $insert The array to insert.
 229  * @param mixed $after The key to insert after
 230  * @return array
 231  */
 232 function wfArrayInsertAfter( array $array, array $insert, $after ) {
 233         // Find the offset of the element to insert after.
 234         $keys = array_keys( $array );
 235         $offsetByKey = array_flip( $keys );
 236
 237         $offset = $offsetByKey[$after];
 238
 239         // Insert at the specified offset
 240         $before = array_slice( $array, 0, $offset + 1, true );
 241         $after = array_slice( $array, $offset + 1, count( $array ) - $offset, true );
 242
 243         $output = $before + $insert + $after;
 244
 245         return $output;
 246 }
 247
 248 /**
 249  * Recursively converts the parameter (an object) to an array with the same data
 250  *
 251  * @param object|array $objOrArray
 252  * @param bool $recursive
 253  * @return array
 254  */
 255 function wfObjectToArray( $objOrArray, $recursive = true ) {
 256         $array = [];
 257         if ( is_object( $objOrArray ) ) {
 258                 $objOrArray = get_object_vars( $objOrArray );
 259         }
 260         foreach ( $objOrArray as $key => $value ) {
 261                 if ( $recursive && ( is_object( $value ) || is_array( $value ) ) ) {
 262                         $value = wfObjectToArray( $value );
 263                 }
 264
 265                 $array[$key] = $value;
 266         }
 267
 268         return $array;
 269 }
 270
 271 /**
 272  * Get a random decimal value between 0 and 1, in a way
 273  * not likely to give duplicate values for any realistic
 274  * number of articles.
 275  *
 276  * @note This is designed for use in relation to Special:RandomPage
 277  *       and the page_random database field.
 278  *
 279  * @return string
 280  */
 281 function wfRandom() {
 282         // The maximum random value is "only" 2^31-1, so get two random
 283         // values to reduce the chance of dupes
 284         $max = mt_getrandmax() + 1;
 285         $rand = number_format( ( mt_rand() * $max + mt_rand() ) / $max / $max, 12, '.', '' );
 286         return $rand;
 287 }
 288
 289 /**
 290  * Get a random string containing a number of pseudo-random hex characters.
 291  *
 292  * @note This is not secure, if you are trying to generate some sort
 293  *       of token please use MWCryptRand instead.
 294  *
 295  * @param int $length The length of the string to generate
 296  * @return string
 297  * @since 1.20
 298  */
 299 function wfRandomString( $length = 32 ) {
 300         $str = '';
 301         for ( $n = 0; $n < $length; $n += 7 ) {
 302                 $str .= sprintf( '%07x', mt_rand() & 0xfffffff );
 303         }
 304         return substr( $str, 0, $length );
 305 }
 306
 307 /**
 308  * We want some things to be included as literal characters in our title URLs
 309  * for prettiness, which urlencode encodes by default.  According to RFC 1738,
 310  * all of the following should be safe:
 311  *
 312  * ;:@&=$-_.+!*'(),
 313  *
 314  * RFC 1738 says ~ is unsafe, however RFC 3986 considers it an unreserved
 315  * character which should not be encoded. More importantly, google chrome
 316  * always converts %7E back to ~, and converting it in this function can
 317  * cause a redirect loop (T105265).
 318  *
 319  * But + is not safe because it's used to indicate a space; &= are only safe in
 320  * paths and not in queries (and we don't distinguish here); ' seems kind of
 321  * scary; and urlencode() doesn't touch -_. to begin with.  Plus, although /
 322  * is reserved, we don't care.  So the list we unescape is:
 323  *
 324  * ;:@$!*(),/~
 325  *
 326  * However, IIS7 redirects fail when the url contains a colon (see T24709),
 327  * so no fancy : for IIS7.
 328  *
 329  * %2F in the page titles seems to fatally break for some reason.
 330  *
 331  * @param string $s
 332  * @return string
 333  */
 334 function wfUrlencode( $s ) {
 335         static $needle;
 336
 337         if ( is_null( $s ) ) {
 338                 $needle = null;
 339                 return '';
 340         }
 341
 342         if ( is_null( $needle ) ) {
 343                 $needle = [ '%3B', '%40', '%24', '%21', '%2A', '%28', '%29', '%2C', '%2F', '%7E' ];
 344                 if ( !isset( $_SERVER['SERVER_SOFTWARE'] ) ||
 345                         ( strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/7' ) === false )
 346                 ) {
 347                         $needle[] = '%3A';
 348                 }
 349         }
 350
 351         $s = urlencode( $s );
 352         $s = str_ireplace(
 353                 $needle,
 354                 [ ';', '@', '$', '!', '*', '(', ')', ',', '/', '~', ':' ],
 355                 $s
 356         );
 357
 358         return $s;
 359 }
 360
 361 /**
 362  * This function takes one or two arrays as input, and returns a CGI-style string, e.g.
 363  * "days=7&limit=100". Options in the first array override options in the second.
 364  * Options set to null or false will not be output.
 365  *
 366  * @param array $array1 ( String|Array )
 367  * @param array|null $array2 ( String|Array )
 368  * @param string $prefix
 369  * @return string
 370  */
 371 function wfArrayToCgi( $array1, $array2 = null, $prefix = '' ) {
 372         if ( !is_null( $array2 ) ) {
 373                 $array1 = $array1 + $array2;
 374         }
 375
 376         $cgi = '';
 377         foreach ( $array1 as $key => $value ) {
 378                 if ( !is_null( $value ) && $value !== false ) {
 379                         if ( $cgi != '' ) {
 380                                 $cgi .= '&';
 381                         }
 382                         if ( $prefix !== '' ) {
 383                                 $key = $prefix . "[$key]";
 384                         }
 385                         if ( is_array( $value ) ) {
 386                                 $firstTime = true;
 387                                 foreach ( $value as $k => $v ) {
 388                                         $cgi .= $firstTime ? '' : '&';
 389                                         if ( is_array( $v ) ) {
 390                                                 $cgi .= wfArrayToCgi( $v, null, $key . "[$k]" );
 391                                         } else {
 392                                                 $cgi .= urlencode( $key . "[$k]" ) . '=' . urlencode( $v );
 393                                         }
 394                                         $firstTime = false;
 395                                 }
 396                         } else {
 397                                 if ( is_object( $value ) ) {
 398                                         $value = $value->__toString();
 399                                 }
 400                                 $cgi .= urlencode( $key ) . '=' . urlencode( $value );
 401                         }
 402                 }
 403         }
 404         return $cgi;
 405 }
 406
 407 /**
 408  * This is the logical opposite of wfArrayToCgi(): it accepts a query string as
 409  * its argument and returns the same string in array form.  This allows compatibility
 410  * with legacy functions that accept raw query strings instead of nice
 411  * arrays.  Of course, keys and values are urldecode()d.
 412  *
 413  * @param string $query Query string
 414  * @return string[] Array version of input
 415  */
 416 function wfCgiToArray( $query ) {
 417         if ( isset( $query[0] ) && $query[0] == '?' ) {
 418                 $query = substr( $query, 1 );
 419         }
 420         $bits = explode( '&', $query );
 421         $ret = [];
 422         foreach ( $bits as $bit ) {
 423                 if ( $bit === '' ) {
 424                         continue;
 425                 }
 426                 if ( strpos( $bit, '=' ) === false ) {
 427                         // Pieces like &qwerty become 'qwerty' => '' (at least this is what php does)
 428                         $key = $bit;
 429                         $value = '';
 430                 } else {
 431                         list( $key, $value ) = explode( '=', $bit );
 432                 }
 433                 $key = urldecode( $key );
 434                 $value = urldecode( $value );
 435                 if ( strpos( $key, '[' ) !== false ) {
 436                         $keys = array_reverse( explode( '[', $key ) );
 437                         $key = array_pop( $keys );
 438                         $temp = $value;
 439                         foreach ( $keys as $k ) {
 440                                 $k = substr( $k, 0, -1 );
 441                                 $temp = [ $k => $temp ];
 442                         }
 443                         if ( isset( $ret[$key] ) ) {
 444                                 $ret[$key] = array_merge( $ret[$key], $temp );
 445                         } else {
 446                                 $ret[$key] = $temp;
 447                         }
 448                 } else {
 449                         $ret[$key] = $value;
 450                 }
 451         }
 452         return $ret;
 453 }
 454
 455 /**
 456  * Append a query string to an existing URL, which may or may not already
 457  * have query string parameters already. If so, they will be combined.
 458  *
 459  * @param string $url
 460  * @param string|string[] $query String or associative array
 461  * @return string
 462  */
 463 function wfAppendQuery( $url, $query ) {
 464         if ( is_array( $query ) ) {
 465                 $query = wfArrayToCgi( $query );
 466         }
 467         if ( $query != '' ) {
 468                 // Remove the fragment, if there is one
 469                 $fragment = false;
 470                 $hashPos = strpos( $url, '#' );
 471                 if ( $hashPos !== false ) {
 472                         $fragment = substr( $url, $hashPos );
 473                         $url = substr( $url, 0, $hashPos );
 474                 }
 475
 476                 // Add parameter
 477                 if ( false === strpos( $url, '?' ) ) {
 478                         $url .= '?';
 479                 } else {
 480                         $url .= '&';
 481                 }
 482                 $url .= $query;
 483
 484                 // Put the fragment back
 485                 if ( $fragment !== false ) {
 486                         $url .= $fragment;
 487                 }
 488         }
 489         return $url;
 490 }
 491
 492 /**
 493  * Expand a potentially local URL to a fully-qualified URL. Assumes $wgServer
 494  * is correct.
 495  *
 496  * The meaning of the PROTO_* constants is as follows:
 497  * PROTO_HTTP: Output a URL starting with http://
 498  * PROTO_HTTPS: Output a URL starting with https://
 499  * PROTO_RELATIVE: Output a URL starting with // (protocol-relative URL)
 500  * PROTO_CURRENT: Output a URL starting with either http:// or https:// , depending
 501  *    on which protocol was used for the current incoming request
 502  * PROTO_CANONICAL: For URLs without a domain, like /w/index.php , use $wgCanonicalServer.
 503  *    For protocol-relative URLs, use the protocol of $wgCanonicalServer
 504  * PROTO_INTERNAL: Like PROTO_CANONICAL, but uses $wgInternalServer instead of $wgCanonicalServer
 505  *
 506  * @todo this won't work with current-path-relative URLs
 507  * like "subdir/foo.html", etc.
 508  *
 509  * @param string $url Either fully-qualified or a local path + query
 510  * @param string|int|null $defaultProto One of the PROTO_* constants. Determines the
 511  *    protocol to use if $url or $wgServer is protocol-relative
 512  * @return string|false Fully-qualified URL, current-path-relative URL or false if
 513  *    no valid URL can be constructed
 514  */
 515 function wfExpandUrl( $url, $defaultProto = PROTO_CURRENT ) {
 516         global $wgServer, $wgCanonicalServer, $wgInternalServer, $wgRequest,
 517                 $wgHttpsPort;
 518         if ( $defaultProto === PROTO_CANONICAL ) {
 519                 $serverUrl = $wgCanonicalServer;
 520         } elseif ( $defaultProto === PROTO_INTERNAL && $wgInternalServer !== false ) {
 521                 // Make $wgInternalServer fall back to $wgServer if not set
 522                 $serverUrl = $wgInternalServer;
 523         } else {
 524                 $serverUrl = $wgServer;
 525                 if ( $defaultProto === PROTO_CURRENT ) {
 526                         $defaultProto = $wgRequest->getProtocol() . '://';
 527                 }
 528         }
 529
 530         // Analyze $serverUrl to obtain its protocol
 531         $bits = wfParseUrl( $serverUrl );
 532         $serverHasProto = $bits && $bits['scheme'] != '';
 533
 534         if ( $defaultProto === PROTO_CANONICAL || $defaultProto === PROTO_INTERNAL ) {
 535                 if ( $serverHasProto ) {
 536                         $defaultProto = $bits['scheme'] . '://';
 537                 } else {
 538                         // $wgCanonicalServer or $wgInternalServer doesn't have a protocol.
 539                         // This really isn't supposed to happen. Fall back to HTTP in this
 540                         // ridiculous case.
 541                         $defaultProto = PROTO_HTTP;
 542                 }
 543         }
 544
 545         $defaultProtoWithoutSlashes = substr( $defaultProto, 0, -2 );
 546
 547         if ( substr( $url, 0, 2 ) == '//' ) {
 548                 $url = $defaultProtoWithoutSlashes . $url;
 549         } elseif ( substr( $url, 0, 1 ) == '/' ) {
 550                 // If $serverUrl is protocol-relative, prepend $defaultProtoWithoutSlashes,
 551                 // otherwise leave it alone.
 552                 if ( $serverHasProto ) {
 553                         $url = $serverUrl . $url;
 554                 } else {
 555                         // If an HTTPS URL is synthesized from a protocol-relative $wgServer, allow the
 556                         // user to override the port number (T67184)
 557                         if ( $defaultProto === PROTO_HTTPS && $wgHttpsPort != 443 ) {
 558                                 if ( isset( $bits['port'] ) ) {
 559                                         throw new Exception( 'A protocol-relative $wgServer may not contain a port number' );
 560                                 }
 561                                 $url = $defaultProtoWithoutSlashes . $serverUrl . ':' . $wgHttpsPort . $url;
 562                         } else {
 563                                 $url = $defaultProtoWithoutSlashes . $serverUrl . $url;
 564                         }
 565                 }
 566         }
 567
 568         $bits = wfParseUrl( $url );
 569
 570         if ( $bits && isset( $bits['path'] ) ) {
 571                 $bits['path'] = wfRemoveDotSegments( $bits['path'] );
 572                 return wfAssembleUrl( $bits );
 573         } elseif ( $bits ) {
 574                 # No path to expand
 575                 return $url;
 576         } elseif ( substr( $url, 0, 1 ) != '/' ) {
 577                 # URL is a relative path
 578                 return wfRemoveDotSegments( $url );
 579         }
 580
 581         # Expanded URL is not valid.
 582         return false;
 583 }
 584
 585 /**
 586  * Get the wiki's "server", i.e. the protocol and host part of the URL, with a
 587  * protocol specified using a PROTO_* constant as in wfExpandUrl()
 588  *
 589  * @since 1.32
 590  * @param string|int|null $proto One of the PROTO_* constants.
 591  * @return string The URL
 592  */
 593 function wfGetServerUrl( $proto ) {
 594         $url = wfExpandUrl( '/', $proto );
 595         return substr( $url, 0, -1 );
 596 }
 597
 598 /**
 599  * This function will reassemble a URL parsed with wfParseURL.  This is useful
 600  * if you need to edit part of a URL and put it back together.
 601  *
 602  * This is the basic structure used (brackets contain keys for $urlParts):
 603  * [scheme][delimiter][user]:[pass]@[host]:[port][path]?[query]#[fragment]
 604  *
 605  * @todo Need to integrate this into wfExpandUrl (see T34168)
 606  *
 607  * @since 1.19
 608  * @param array $urlParts URL parts, as output from wfParseUrl
 609  * @return string URL assembled from its component parts
 610  */
 611 function wfAssembleUrl( $urlParts ) {
 612         $result = '';
 613
 614         if ( isset( $urlParts['delimiter'] ) ) {
 615                 if ( isset( $urlParts['scheme'] ) ) {
 616                         $result .= $urlParts['scheme'];
 617                 }
 618
 619                 $result .= $urlParts['delimiter'];
 620         }
 621
 622         if ( isset( $urlParts['host'] ) ) {
 623                 if ( isset( $urlParts['user'] ) ) {
 624                         $result .= $urlParts['user'];
 625                         if ( isset( $urlParts['pass'] ) ) {
 626                                 $result .= ':' . $urlParts['pass'];
 627                         }
 628                         $result .= '@';
 629                 }
 630
 631                 $result .= $urlParts['host'];
 632
 633                 if ( isset( $urlParts['port'] ) ) {
 634                         $result .= ':' . $urlParts['port'];
 635                 }
 636         }
 637
 638         if ( isset( $urlParts['path'] ) ) {
 639                 $result .= $urlParts['path'];
 640         }
 641
 642         if ( isset( $urlParts['query'] ) ) {
 643                 $result .= '?' . $urlParts['query'];
 644         }
 645
 646         if ( isset( $urlParts['fragment'] ) ) {
 647                 $result .= '#' . $urlParts['fragment'];
 648         }
 649
 650         return $result;
 651 }
 652
 653 /**
 654  * Remove all dot-segments in the provided URL path.  For example,
 655  * '/a/./b/../c/' becomes '/a/c/'.  For details on the algorithm, please see
 656  * RFC3986 section 5.2.4.
 657  *
 658  * @todo Need to integrate this into wfExpandUrl (see T34168)
 659  *
 660  * @since 1.19
 661  *
 662  * @param string $urlPath URL path, potentially containing dot-segments
 663  * @return string URL path with all dot-segments removed
 664  */
 665 function wfRemoveDotSegments( $urlPath ) {
 666         $output = '';
 667         $inputOffset = 0;
 668         $inputLength = strlen( $urlPath );
 669
 670         while ( $inputOffset < $inputLength ) {
 671                 $prefixLengthOne = substr( $urlPath, $inputOffset, 1 );
 672                 $prefixLengthTwo = substr( $urlPath, $inputOffset, 2 );
 673                 $prefixLengthThree = substr( $urlPath, $inputOffset, 3 );
 674                 $prefixLengthFour = substr( $urlPath, $inputOffset, 4 );
 675                 $trimOutput = false;
 676
 677                 if ( $prefixLengthTwo == './' ) {
 678                         # Step A, remove leading "./"
 679                         $inputOffset += 2;
 680                 } elseif ( $prefixLengthThree == '../' ) {
 681                         # Step A, remove leading "../"
 682                         $inputOffset += 3;
 683                 } elseif ( ( $prefixLengthTwo == '/.' ) && ( $inputOffset + 2 == $inputLength ) ) {
 684                         # Step B, replace leading "/.$" with "/"
 685                         $inputOffset += 1;
 686                         $urlPath[$inputOffset] = '/';
 687                 } elseif ( $prefixLengthThree == '/./' ) {
 688                         # Step B, replace leading "/./" with "/"
 689                         $inputOffset += 2;
 690                 } elseif ( $prefixLengthThree == '/..' && ( $inputOffset + 3 == $inputLength ) ) {
 691                         # Step C, replace leading "/..$" with "/" and
 692                         # remove last path component in output
 693                         $inputOffset += 2;
 694                         $urlPath[$inputOffset] = '/';
 695                         $trimOutput = true;
 696                 } elseif ( $prefixLengthFour == '/../' ) {
 697                         # Step C, replace leading "/../" with "/" and
 698                         # remove last path component in output
 699                         $inputOffset += 3;
 700                         $trimOutput = true;
 701                 } elseif ( ( $prefixLengthOne == '.' ) && ( $inputOffset + 1 == $inputLength ) ) {
 702                         # Step D, remove "^.$"
 703                         $inputOffset += 1;
 704                 } elseif ( ( $prefixLengthTwo == '..' ) && ( $inputOffset + 2 == $inputLength ) ) {
 705                         # Step D, remove "^..$"
 706                         $inputOffset += 2;
 707                 } else {
 708                         # Step E, move leading path segment to output
 709                         if ( $prefixLengthOne == '/' ) {
 710                                 $slashPos = strpos( $urlPath, '/', $inputOffset + 1 );
 711                         } else {
 712                                 $slashPos = strpos( $urlPath, '/', $inputOffset );
 713                         }
 714                         if ( $slashPos === false ) {
 715                                 $output .= substr( $urlPath, $inputOffset );
 716                                 $inputOffset = $inputLength;
 717                         } else {
 718                                 $output .= substr( $urlPath, $inputOffset, $slashPos - $inputOffset );
 719                                 $inputOffset += $slashPos - $inputOffset;
 720                         }
 721                 }
 722
 723                 if ( $trimOutput ) {
 724                         $slashPos = strrpos( $output, '/' );
 725                         if ( $slashPos === false ) {
 726                                 $output = '';
 727                         } else {
 728                                 $output = substr( $output, 0, $slashPos );
 729                         }
 730                 }
 731         }
 732
 733         return $output;
 734 }
 735
 736 /**
 737  * Returns a regular expression of url protocols
 738  *
 739  * @param bool $includeProtocolRelative If false, remove '//' from the returned protocol list.
 740  *        DO NOT USE this directly, use wfUrlProtocolsWithoutProtRel() instead
 741  * @return string
 742  */
 743 function wfUrlProtocols( $includeProtocolRelative = true ) {
 744         global $wgUrlProtocols;
 745
 746         // Cache return values separately based on $includeProtocolRelative
 747         static $withProtRel = null, $withoutProtRel = null;
 748         $cachedValue = $includeProtocolRelative ? $withProtRel : $withoutProtRel;
 749         if ( !is_null( $cachedValue ) ) {
 750                 return $cachedValue;
 751         }
 752
 753         // Support old-style $wgUrlProtocols strings, for backwards compatibility
 754         // with LocalSettings files from 1.5
 755         if ( is_array( $wgUrlProtocols ) ) {
 756                 $protocols = [];
 757                 foreach ( $wgUrlProtocols as $protocol ) {
 758                         // Filter out '//' if !$includeProtocolRelative
 759                         if ( $includeProtocolRelative || $protocol !== '//' ) {
 760                                 $protocols[] = preg_quote( $protocol, '/' );
 761                         }
 762                 }
 763
 764                 $retval = implode( '|', $protocols );
 765         } else {
 766                 // Ignore $includeProtocolRelative in this case
 767                 // This case exists for pre-1.6 compatibility, and we can safely assume
 768                 // that '//' won't appear in a pre-1.6 config because protocol-relative
 769                 // URLs weren't supported until 1.18
 770                 $retval = $wgUrlProtocols;
 771         }
 772
 773         // Cache return value
 774         if ( $includeProtocolRelative ) {
 775                 $withProtRel = $retval;
 776         } else {
 777                 $withoutProtRel = $retval;
 778         }
 779         return $retval;
 780 }
 781
 782 /**
 783  * Like wfUrlProtocols(), but excludes '//' from the protocol list. Use this if
 784  * you need a regex that matches all URL protocols but does not match protocol-
 785  * relative URLs
 786  * @return string
 787  */
 788 function wfUrlProtocolsWithoutProtRel() {
 789         return wfUrlProtocols( false );
 790 }
 791
 792 /**
 793  * parse_url() work-alike, but non-broken.  Differences:
 794  *
 795  * 1) Does not raise warnings on bad URLs (just returns false).
 796  * 2) Handles protocols that don't use :// (e.g., mailto: and news:, as well as
 797  *    protocol-relative URLs) correctly.
 798  * 3) Adds a "delimiter" element to the array (see (2)).
 799  * 4) Verifies that the protocol is on the $wgUrlProtocols whitelist.
 800  * 5) Rejects some invalid URLs that parse_url doesn't, e.g. the empty string or URLs starting with
 801  *    a line feed character.
 802  *
 803  * @param string $url A URL to parse
 804  * @return string[]|bool Bits of the URL in an associative array, or false on failure.
 805  *   Possible fields:
 806  *   - scheme: URI scheme (protocol), e.g. 'http', 'mailto'. Lowercase, always present, but can
 807  *       be an empty string for protocol-relative URLs.
 808  *   - delimiter: either '://', ':' or '//'. Always present.
 809  *   - host: domain name / IP. Always present, but could be an empty string, e.g. for file: URLs.
 810  *   - user: user name, e.g. for HTTP Basic auth URLs such as http://user:pass@example.com/
 811  *       Missing when there is no username.
 812  *   - pass: password, same as above.
 813  *   - path: path including the leading /. Will be missing when empty (e.g. 'http://example.com')
 814  *   - query: query string (as a string; see wfCgiToArray() for parsing it), can be missing.
 815  *   - fragment: the part after #, can be missing.
 816  */
 817 function wfParseUrl( $url ) {
 818         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
 819
 820         // Protocol-relative URLs are handled really badly by parse_url(). It's so
 821         // bad that the easiest way to handle them is to just prepend 'http:' and
 822         // strip the protocol out later.
 823         $wasRelative = substr( $url, 0, 2 ) == '//';
 824         if ( $wasRelative ) {
 825                 $url = "http:$url";
 826         }
 827         Wikimedia\suppressWarnings();
 828         $bits = parse_url( $url );
 829         Wikimedia\restoreWarnings();
 830         // parse_url() returns an array without scheme for some invalid URLs, e.g.
 831         // parse_url("%0Ahttp://example.com") == [ 'host' => '%0Ahttp', 'path' => 'example.com' ]
 832         if ( !$bits || !isset( $bits['scheme'] ) ) {
 833                 return false;
 834         }
 835
 836         // parse_url() incorrectly handles schemes case-sensitively. Convert it to lowercase.
 837         $bits['scheme'] = strtolower( $bits['scheme'] );
 838
 839         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
 840         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
 841                 $bits['delimiter'] = '://';
 842         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
 843                 $bits['delimiter'] = ':';
 844                 // parse_url detects for news: and mailto: the host part of an url as path
 845                 // We have to correct this wrong detection
 846                 if ( isset( $bits['path'] ) ) {
 847                         $bits['host'] = $bits['path'];
 848                         $bits['path'] = '';
 849                 }
 850         } else {
 851                 return false;
 852         }
 853
 854         /* Provide an empty host for eg. file:/// urls (see T30627) */
 855         if ( !isset( $bits['host'] ) ) {
 856                 $bits['host'] = '';
 857
 858                 // See T47069
 859                 if ( isset( $bits['path'] ) ) {
 860                         /* parse_url loses the third / for file:///c:/ urls (but not on variants) */
 861                         if ( substr( $bits['path'], 0, 1 ) !== '/' ) {
 862                                 $bits['path'] = '/' . $bits['path'];
 863                         }
 864                 } else {
 865                         $bits['path'] = '';
 866                 }
 867         }
 868
 869         // If the URL was protocol-relative, fix scheme and delimiter
 870         if ( $wasRelative ) {
 871                 $bits['scheme'] = '';
 872                 $bits['delimiter'] = '//';
 873         }
 874         return $bits;
 875 }
 876
 877 /**
 878  * Take a URL, make sure it's expanded to fully qualified, and replace any
 879  * encoded non-ASCII Unicode characters with their UTF-8 original forms
 880  * for more compact display and legibility for local audiences.
 881  *
 882  * @todo handle punycode domains too
 883  *
 884  * @param string $url
 885  * @return string
 886  */
 887 function wfExpandIRI( $url ) {
 888         return preg_replace_callback(
 889                 '/((?:%[89A-F][0-9A-F])+)/i',
 890                 function ( array $matches ) {
 891                         return urldecode( $matches[1] );
 892                 },
 893                 wfExpandUrl( $url )
 894         );
 895 }
 896
 897 /**
 898  * Make URL indexes, appropriate for the el_index field of externallinks.
 899  *
 900  * @param string $url
 901  * @return array
 902  */
 903 function wfMakeUrlIndexes( $url ) {
 904         $bits = wfParseUrl( $url );
 905
 906         // Reverse the labels in the hostname, convert to lower case
 907         // For emails reverse domainpart only
 908         if ( $bits['scheme'] == 'mailto' ) {
 909                 $mailparts = explode( '@', $bits['host'], 2 );
 910                 if ( count( $mailparts ) === 2 ) {
 911                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
 912                 } else {
 913                         // No domain specified, don't mangle it
 914                         $domainpart = '';
 915                 }
 916                 $reversedHost = $domainpart . '@' . $mailparts[0];
 917         } else {
 918                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
 919         }
 920         // Add an extra dot to the end
 921         // Why? Is it in wrong place in mailto links?
 922         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
 923                 $reversedHost .= '.';
 924         }
 925         // Reconstruct the pseudo-URL
 926         $prot = $bits['scheme'];
 927         $index = $prot . $bits['delimiter'] . $reversedHost;
 928         // Leave out user and password. Add the port, path, query and fragment
 929         if ( isset( $bits['port'] ) ) {
 930                 $index .= ':' . $bits['port'];
 931         }
 932         if ( isset( $bits['path'] ) ) {
 933                 $index .= $bits['path'];
 934         } else {
 935                 $index .= '/';
 936         }
 937         if ( isset( $bits['query'] ) ) {
 938                 $index .= '?' . $bits['query'];
 939         }
 940         if ( isset( $bits['fragment'] ) ) {
 941                 $index .= '#' . $bits['fragment'];
 942         }
 943
 944         if ( $prot == '' ) {
 945                 return [ "http:$index", "https:$index" ];
 946         } else {
 947                 return [ $index ];
 948         }
 949 }
 950
 951 /**
 952  * Check whether a given URL has a domain that occurs in a given set of domains
 953  * @param string $url
 954  * @param array $domains Array of domains (strings)
 955  * @return bool True if the host part of $url ends in one of the strings in $domains
 956  */
 957 function wfMatchesDomainList( $url, $domains ) {
 958         $bits = wfParseUrl( $url );
 959         if ( is_array( $bits ) && isset( $bits['host'] ) ) {
 960                 $host = '.' . $bits['host'];
 961                 foreach ( (array)$domains as $domain ) {
 962                         $domain = '.' . $domain;
 963                         if ( substr( $host, -strlen( $domain ) ) === $domain ) {
 964                                 return true;
 965                         }
 966                 }
 967         }
 968         return false;
 969 }
 970
 971 /**
 972  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
 973  * In normal operation this is a NOP.
 974  *
 975  * Controlling globals:
 976  * $wgDebugLogFile - points to the log file
 977  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
 978  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
 979  *
 980  * @since 1.25 support for additional context data
 981  *
 982  * @param string $text
 983  * @param string|bool $dest Destination of the message:
 984  *     - 'all': both to the log and HTML (debug toolbar or HTML comments)
 985  *     - 'private': excluded from HTML output
 986  *   For backward compatibility, it can also take a boolean:
 987  *     - true: same as 'all'
 988  *     - false: same as 'private'
 989  * @param array $context Additional logging context data
 990  */
 991 function wfDebug( $text, $dest = 'all', array $context = [] ) {
 992         global $wgDebugRawPage, $wgDebugLogPrefix;
 993         global $wgDebugTimestamps;
 994
 995         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
 996                 return;
 997         }
 998
 999         $text = trim( $text );
1000
1001         if ( $wgDebugTimestamps ) {
1002                 $context['seconds_elapsed'] = sprintf(
1003                         '%6.4f',
1004                         microtime( true ) - $_SERVER['REQUEST_TIME_FLOAT']
1005                 );
1006                 $context['memory_used'] = sprintf(
1007                         '%5.1fM',
1008                         ( memory_get_usage( true ) / ( 1024 * 1024 ) )
1009                 );
1010         }
1011
1012         if ( $wgDebugLogPrefix !== '' ) {
1013                 $context['prefix'] = $wgDebugLogPrefix;
1014         }
1015         $context['private'] = ( $dest === false || $dest === 'private' );
1016
1017         $logger = LoggerFactory::getInstance( 'wfDebug' );
1018         $logger->debug( $text, $context );
1019 }
1020
1021 /**
1022  * Returns true if debug logging should be suppressed if $wgDebugRawPage = false
1023  * @return bool
1024  */
1025 function wfIsDebugRawPage() {
1026         static $cache;
1027         if ( $cache !== null ) {
1028                 return $cache;
1029         }
1030         // Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
1031         // phpcs:ignore MediaWiki.Usage.SuperGlobalsUsage.SuperGlobals
1032         if ( ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' )
1033                 || (
1034                         isset( $_SERVER['SCRIPT_NAME'] )
1035                         && substr( $_SERVER['SCRIPT_NAME'], -8 ) == 'load.php'
1036                 )
1037         ) {
1038                 $cache = true;
1039         } else {
1040                 $cache = false;
1041         }
1042         return $cache;
1043 }
1044
1045 /**
1046  * Send a line giving PHP memory usage.
1047  *
1048  * @param bool $exact Print exact byte values instead of kibibytes (default: false)
1049  */
1050 function wfDebugMem( $exact = false ) {
1051         $mem = memory_get_usage();
1052         if ( !$exact ) {
1053                 $mem = floor( $mem / 1024 ) . ' KiB';
1054         } else {
1055                 $mem .= ' B';
1056         }
1057         wfDebug( "Memory usage: $mem\n" );
1058 }
1059
1060 /**
1061  * Send a line to a supplementary debug log file, if configured, or main debug
1062  * log if not.
1063  *
1064  * To configure a supplementary log file, set $wgDebugLogGroups[$logGroup] to
1065  * a string filename or an associative array mapping 'destination' to the
1066  * desired filename. The associative array may also contain a 'sample' key
1067  * with an integer value, specifying a sampling factor. Sampled log events
1068  * will be emitted with a 1 in N random chance.
1069  *
1070  * @since 1.23 support for sampling log messages via $wgDebugLogGroups.
1071  * @since 1.25 support for additional context data
1072  * @since 1.25 sample behavior dependent on configured $wgMWLoggerDefaultSpi
1073  *
1074  * @param string $logGroup
1075  * @param string $text
1076  * @param string|bool $dest Destination of the message:
1077  *     - 'all': both to the log and HTML (debug toolbar or HTML comments)
1078  *     - 'private': only to the specific log if set in $wgDebugLogGroups and
1079  *       discarded otherwise
1080  *   For backward compatibility, it can also take a boolean:
1081  *     - true: same as 'all'
1082  *     - false: same as 'private'
1083  * @param array $context Additional logging context data
1084  */
1085 function wfDebugLog(
1086         $logGroup, $text, $dest = 'all', array $context = []
1087 ) {
1088         $text = trim( $text );
1089
1090         $logger = LoggerFactory::getInstance( $logGroup );
1091         $context['private'] = ( $dest === false || $dest === 'private' );
1092         $logger->info( $text, $context );
1093 }
1094
1095 /**
1096  * Log for database errors
1097  *
1098  * @since 1.25 support for additional context data
1099  *
1100  * @param string $text Database error message.
1101  * @param array $context Additional logging context data
1102  */
1103 function wfLogDBError( $text, array $context = [] ) {
1104         $logger = LoggerFactory::getInstance( 'wfLogDBError' );
1105         $logger->error( trim( $text ), $context );
1106 }
1107
1108 /**
1109  * Throws a warning that $function is deprecated
1110  *
1111  * @param string $function
1112  * @param string|bool $version Version of MediaWiki that the function
1113  *    was deprecated in (Added in 1.19).
1114  * @param string|bool $component Added in 1.19.
1115  * @param int $callerOffset How far up the call stack is the original
1116  *    caller. 2 = function that called the function that called
1117  *    wfDeprecated (Added in 1.20)
1118  *
1119  * @return null
1120  */
1121 function wfDeprecated( $function, $version = false, $component = false, $callerOffset = 2 ) {
1122         MWDebug::deprecated( $function, $version, $component, $callerOffset + 1 );
1123 }
1124
1125 /**
1126  * Send a warning either to the debug log or in a PHP error depending on
1127  * $wgDevelopmentWarnings. To log warnings in production, use wfLogWarning() instead.
1128  *
1129  * @param string $msg Message to send
1130  * @param int $callerOffset Number of items to go back in the backtrace to
1131  *        find the correct caller (1 = function calling wfWarn, ...)
1132  * @param int $level PHP error level; defaults to E_USER_NOTICE;
1133  *        only used when $wgDevelopmentWarnings is true
1134  */
1135 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
1136         MWDebug::warning( $msg, $callerOffset + 1, $level, 'auto' );
1137 }
1138
1139 /**
1140  * Send a warning as a PHP error and the debug log. This is intended for logging
1141  * warnings in production. For logging development warnings, use WfWarn instead.
1142  *
1143  * @param string $msg Message to send
1144  * @param int $callerOffset Number of items to go back in the backtrace to
1145  *        find the correct caller (1 = function calling wfLogWarning, ...)
1146  * @param int $level PHP error level; defaults to E_USER_WARNING
1147  */
1148 function wfLogWarning( $msg, $callerOffset = 1, $level = E_USER_WARNING ) {
1149         MWDebug::warning( $msg, $callerOffset + 1, $level, 'production' );
1150 }
1151
1152 /**
1153  * Log to a file without getting "file size exceeded" signals.
1154  *
1155  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
1156  * send lines to the specified port, prefixed by the specified prefix and a space.
1157  * @since 1.25 support for additional context data
1158  *
1159  * @param string $text
1160  * @param string $file Filename
1161  * @param array $context Additional logging context data
1162  * @throws MWException
1163  * @deprecated since 1.25 Use \MediaWiki\Logger\LegacyLogger::emit or UDPTransport
1164  */
1165 function wfErrorLog( $text, $file, array $context = [] ) {
1166         wfDeprecated( __METHOD__, '1.25' );
1167         $logger = LoggerFactory::getInstance( 'wfErrorLog' );
1168         $context['destination'] = $file;
1169         $logger->info( trim( $text ), $context );
1170 }
1171
1172 /**
1173  * @todo document
1174  * @todo Move logic to MediaWiki.php
1175  */
1176 function wfLogProfilingData() {
1177         global $wgDebugLogGroups, $wgDebugRawPage;
1178
1179         $context = RequestContext::getMain();
1180         $request = $context->getRequest();
1181
1182         $profiler = Profiler::instance();
1183         $profiler->setContext( $context );
1184         $profiler->logData();
1185
1186         // Send out any buffered statsd metrics as needed
1187         MediaWiki::emitBufferedStatsdData(
1188                 MediaWikiServices::getInstance()->getStatsdDataFactory(),
1189                 $context->getConfig()
1190         );
1191
1192         // Profiling must actually be enabled...
1193         if ( $profiler instanceof ProfilerStub ) {
1194                 return;
1195         }
1196
1197         if ( isset( $wgDebugLogGroups['profileoutput'] )
1198                 && $wgDebugLogGroups['profileoutput'] === false
1199         ) {
1200                 // Explicitly disabled
1201                 return;
1202         }
1203         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
1204                 return;
1205         }
1206
1207         $ctx = [ 'elapsed' => $request->getElapsedTime() ];
1208         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
1209                 $ctx['forwarded_for'] = $_SERVER['HTTP_X_FORWARDED_FOR'];
1210         }
1211         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
1212                 $ctx['client_ip'] = $_SERVER['HTTP_CLIENT_IP'];
1213         }
1214         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
1215                 $ctx['from'] = $_SERVER['HTTP_FROM'];
1216         }
1217         if ( isset( $ctx['forwarded_for'] ) ||
1218                 isset( $ctx['client_ip'] ) ||
1219                 isset( $ctx['from'] ) ) {
1220                 $ctx['proxy'] = $_SERVER['REMOTE_ADDR'];
1221         }
1222
1223         // Don't load $wgUser at this late stage just for statistics purposes
1224         // @todo FIXME: We can detect some anons even if it is not loaded.
1225         // See User::getId()
1226         $user = $context->getUser();
1227         $ctx['anon'] = $user->isItemLoaded( 'id' ) && $user->isAnon();
1228
1229         // Command line script uses a FauxRequest object which does not have
1230         // any knowledge about an URL and throw an exception instead.
1231         try {
1232                 $ctx['url'] = urldecode( $request->getRequestURL() );
1233         } catch ( Exception $ignored ) {
1234                 // no-op
1235         }
1236
1237         $ctx['output'] = $profiler->getOutput();
1238
1239         $log = LoggerFactory::getInstance( 'profileoutput' );
1240         $log->info( "Elapsed: {elapsed}; URL: <{url}>\n{output}", $ctx );
1241 }
1242
1243 /**
1244  * Increment a statistics counter
1245  *
1246  * @param string $key
1247  * @param int $count
1248  * @return void
1249  */
1250 function wfIncrStats( $key, $count = 1 ) {
1251         $stats = MediaWikiServices::getInstance()->getStatsdDataFactory();
1252         $stats->updateCount( $key, $count );
1253 }
1254
1255 /**
1256  * Check whether the wiki is in read-only mode.
1257  *
1258  * @return bool
1259  */
1260 function wfReadOnly() {
1261         return MediaWikiServices::getInstance()->getReadOnlyMode()
1262                 ->isReadOnly();
1263 }
1264
1265 /**
1266  * Check if the site is in read-only mode and return the message if so
1267  *
1268  * This checks wfConfiguredReadOnlyReason() and the main load balancer
1269  * for replica DB lag. This may result in DB connection being made.
1270  *
1271  * @return string|bool String when in read-only mode; false otherwise
1272  */
1273 function wfReadOnlyReason() {
1274         return MediaWikiServices::getInstance()->getReadOnlyMode()
1275                 ->getReason();
1276 }
1277
1278 /**
1279  * Get the value of $wgReadOnly or the contents of $wgReadOnlyFile.
1280  *
1281  * @return string|bool String when in read-only mode; false otherwise
1282  * @since 1.27
1283  */
1284 function wfConfiguredReadOnlyReason() {
1285         return MediaWikiServices::getInstance()->getConfiguredReadOnlyMode()
1286                 ->getReason();
1287 }
1288
1289 /**
1290  * Return a Language object from $langcode
1291  *
1292  * @param Language|string|bool $langcode Either:
1293  *                  - a Language object
1294  *                  - code of the language to get the message for, if it is
1295  *                    a valid code create a language for that language, if
1296  *                    it is a string but not a valid code then make a basic
1297  *                    language object
1298  *                  - a boolean: if it's false then use the global object for
1299  *                    the current user's language (as a fallback for the old parameter
1300  *                    functionality), or if it is true then use global object
1301  *                    for the wiki's content language.
1302  * @return Language
1303  */
1304 function wfGetLangObj( $langcode = false ) {
1305         # Identify which language to get or create a language object for.
1306         # Using is_object here due to Stub objects.
1307         if ( is_object( $langcode ) ) {
1308                 # Great, we already have the object (hopefully)!
1309                 return $langcode;
1310         }
1311
1312         global $wgLanguageCode;
1313         if ( $langcode === true || $langcode === $wgLanguageCode ) {
1314                 # $langcode is the language code of the wikis content language object.
1315                 # or it is a boolean and value is true
1316                 return MediaWikiServices::getInstance()->getContentLanguage();
1317         }
1318
1319         global $wgLang;
1320         if ( $langcode === false || $langcode === $wgLang->getCode() ) {
1321                 # $langcode is the language code of user language object.
1322                 # or it was a boolean and value is false
1323                 return $wgLang;
1324         }
1325
1326         $validCodes = array_keys( Language::fetchLanguageNames() );
1327         if ( in_array( $langcode, $validCodes ) ) {
1328                 # $langcode corresponds to a valid language.
1329                 return Language::factory( $langcode );
1330         }
1331
1332         # $langcode is a string, but not a valid language code; use content language.
1333         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
1334         return MediaWikiServices::getInstance()->getContentLanguage();
1335 }
1336
1337 /**
1338  * This is the function for getting translated interface messages.
1339  *
1340  * @see Message class for documentation how to use them.
1341  * @see https://www.mediawiki.org/wiki/Manual:Messages_API
1342  *
1343  * This function replaces all old wfMsg* functions.
1344  *
1345  * @param string|string[]|MessageSpecifier $key Message key, or array of keys, or a MessageSpecifier
1346  * @param string|string[] ...$params Normal message parameters
1347  * @return Message
1348  *
1349  * @since 1.17
1350  *
1351  * @see Message::__construct
1352  */
1353 function wfMessage( $key, ...$params ) {
1354         $message = new Message( $key );
1355
1356         // We call Message::params() to reduce code duplication
1357         if ( $params ) {
1358                 $message->params( ...$params );
1359         }
1360
1361         return $message;
1362 }
1363
1364 /**
1365  * This function accepts multiple message keys and returns a message instance
1366  * for the first message which is non-empty. If all messages are empty then an
1367  * instance of the first message key is returned.
1368  *
1369  * @param string ...$keys Message keys
1370  * @return Message
1371  *
1372  * @since 1.18
1373  *
1374  * @see Message::newFallbackSequence
1375  */
1376 function wfMessageFallback( ...$keys ) {
1377         return Message::newFallbackSequence( ...$keys );
1378 }
1379
1380 /**
1381  * Replace message parameter keys on the given formatted output.
1382  *
1383  * @param string $message
1384  * @param array $args
1385  * @return string
1386  * @private
1387  */
1388 function wfMsgReplaceArgs( $message, $args ) {
1389         # Fix windows line-endings
1390         # Some messages are split with explode("\n", $msg)
1391         $message = str_replace( "\r", '', $message );
1392
1393         // Replace arguments
1394         if ( is_array( $args ) && $args ) {
1395                 if ( is_array( $args[0] ) ) {
1396                         $args = array_values( $args[0] );
1397                 }
1398                 $replacementKeys = [];
1399                 foreach ( $args as $n => $param ) {
1400                         $replacementKeys['$' . ( $n + 1 )] = $param;
1401                 }
1402                 $message = strtr( $message, $replacementKeys );
1403         }
1404
1405         return $message;
1406 }
1407
1408 /**
1409  * Fetch server name for use in error reporting etc.
1410  * Use real server name if available, so we know which machine
1411  * in a server farm generated the current page.
1412  *
1413  * @return string
1414  */
1415 function wfHostname() {
1416         static $host;
1417         if ( is_null( $host ) ) {
1418                 # Hostname overriding
1419                 global $wgOverrideHostname;
1420                 if ( $wgOverrideHostname !== false ) {
1421                         # Set static and skip any detection
1422                         $host = $wgOverrideHostname;
1423                         return $host;
1424                 }
1425
1426                 if ( function_exists( 'posix_uname' ) ) {
1427                         // This function not present on Windows
1428                         $uname = posix_uname();
1429                 } else {
1430                         $uname = false;
1431                 }
1432                 if ( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1433                         $host = $uname['nodename'];
1434                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1435                         # Windows computer name
1436                         $host = getenv( 'COMPUTERNAME' );
1437                 } else {
1438                         # This may be a virtual server.
1439                         $host = $_SERVER['SERVER_NAME'];
1440                 }
1441         }
1442         return $host;
1443 }
1444
1445 /**
1446  * Returns a script tag that stores the amount of time it took MediaWiki to
1447  * handle the request in milliseconds as 'wgBackendResponseTime'.
1448  *
1449  * If $wgShowHostnames is true, the script will also set 'wgHostname' to the
1450  * hostname of the server handling the request.
1451  *
1452  * @param string|null $nonce Value from OutputPage::getCSPNonce
1453  * @return string|WrappedString HTML
1454  */
1455 function wfReportTime( $nonce = null ) {
1456         global $wgShowHostnames;
1457
1458         $elapsed = ( microtime( true ) - $_SERVER['REQUEST_TIME_FLOAT'] );
1459         // seconds to milliseconds
1460         $responseTime = round( $elapsed * 1000 );
1461         $reportVars = [ 'wgBackendResponseTime' => $responseTime ];
1462         if ( $wgShowHostnames ) {
1463                 $reportVars['wgHostname'] = wfHostname();
1464         }
1465         return Skin::makeVariablesScript( $reportVars, $nonce );
1466 }
1467
1468 /**
1469  * Safety wrapper for debug_backtrace().
1470  *
1471  * Will return an empty array if debug_backtrace is disabled, otherwise
1472  * the output from debug_backtrace() (trimmed).
1473  *
1474  * @param int $limit This parameter can be used to limit the number of stack frames returned
1475  *
1476  * @return array Array of backtrace information
1477  */
1478 function wfDebugBacktrace( $limit = 0 ) {
1479         static $disabled = null;
1480
1481         if ( is_null( $disabled ) ) {
1482                 $disabled = !function_exists( 'debug_backtrace' );
1483                 if ( $disabled ) {
1484                         wfDebug( "debug_backtrace() is disabled\n" );
1485                 }
1486         }
1487         if ( $disabled ) {
1488                 return [];
1489         }
1490
1491         if ( $limit ) {
1492                 return array_slice( debug_backtrace( DEBUG_BACKTRACE_PROVIDE_OBJECT, $limit + 1 ), 1 );
1493         } else {
1494                 return array_slice( debug_backtrace(), 1 );
1495         }
1496 }
1497
1498 /**
1499  * Get a debug backtrace as a string
1500  *
1501  * @param bool|null $raw If true, the return value is plain text. If false, HTML.
1502  *   Defaults to $wgCommandLineMode if unset.
1503  * @return string
1504  * @since 1.25 Supports $raw parameter.
1505  */
1506 function wfBacktrace( $raw = null ) {
1507         global $wgCommandLineMode;
1508
1509         if ( $raw === null ) {
1510                 $raw = $wgCommandLineMode;
1511         }
1512
1513         if ( $raw ) {
1514                 $frameFormat = "%s line %s calls %s()\n";
1515                 $traceFormat = "%s";
1516         } else {
1517                 $frameFormat = "<li>%s line %s calls %s()</li>\n";
1518                 $traceFormat = "<ul>\n%s</ul>\n";
1519         }
1520
1521         $frames = array_map( function ( $frame ) use ( $frameFormat ) {
1522                 $file = !empty( $frame['file'] ) ? basename( $frame['file'] ) : '-';
1523                 $line = $frame['line'] ?? '-';
1524                 $call = $frame['function'];
1525                 if ( !empty( $frame['class'] ) ) {
1526                         $call = $frame['class'] . $frame['type'] . $call;
1527                 }
1528                 return sprintf( $frameFormat, $file, $line, $call );
1529         }, wfDebugBacktrace() );
1530
1531         return sprintf( $traceFormat, implode( '', $frames ) );
1532 }
1533
1534 /**
1535  * Get the name of the function which called this function
1536  * wfGetCaller( 1 ) is the function with the wfGetCaller() call (ie. __FUNCTION__)
1537  * wfGetCaller( 2 ) [default] is the caller of the function running wfGetCaller()
1538  * wfGetCaller( 3 ) is the parent of that.
1539  *
1540  * @param int $level
1541  * @return string
1542  */
1543 function wfGetCaller( $level = 2 ) {
1544         $backtrace = wfDebugBacktrace( $level + 1 );
1545         if ( isset( $backtrace[$level] ) ) {
1546                 return wfFormatStackFrame( $backtrace[$level] );
1547         } else {
1548                 return 'unknown';
1549         }
1550 }
1551
1552 /**
1553  * Return a string consisting of callers in the stack. Useful sometimes
1554  * for profiling specific points.
1555  *
1556  * @param int $limit The maximum depth of the stack frame to return, or false for the entire stack.
1557  * @return string
1558  */
1559 function wfGetAllCallers( $limit = 3 ) {
1560         $trace = array_reverse( wfDebugBacktrace() );
1561         if ( !$limit || $limit > count( $trace ) - 1 ) {
1562                 $limit = count( $trace ) - 1;
1563         }
1564         $trace = array_slice( $trace, -$limit - 1, $limit );
1565         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1566 }
1567
1568 /**
1569  * Return a string representation of frame
1570  *
1571  * @param array $frame
1572  * @return string
1573  */
1574 function wfFormatStackFrame( $frame ) {
1575         if ( !isset( $frame['function'] ) ) {
1576                 return 'NO_FUNCTION_GIVEN';
1577         }
1578         return isset( $frame['class'] ) && isset( $frame['type'] ) ?
1579                 $frame['class'] . $frame['type'] . $frame['function'] :
1580                 $frame['function'];
1581 }
1582
1583 /* Some generic result counters, pulled out of SearchEngine */
1584
1585 /**
1586  * @todo document
1587  *
1588  * @param int $offset
1589  * @param int $limit
1590  * @return string
1591  */
1592 function wfShowingResults( $offset, $limit ) {
1593         return wfMessage( 'showingresults' )->numParams( $limit, $offset + 1 )->parse();
1594 }
1595
1596 /**
1597  * Whether the client accept gzip encoding
1598  *
1599  * Uses the Accept-Encoding header to check if the client supports gzip encoding.
1600  * Use this when considering to send a gzip-encoded response to the client.
1601  *
1602  * @param bool $force Forces another check even if we already have a cached result.
1603  * @return bool
1604  */
1605 function wfClientAcceptsGzip( $force = false ) {
1606         static $result = null;
1607         if ( $result === null || $force ) {
1608                 $result = false;
1609                 if ( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1610                         # @todo FIXME: We may want to blacklist some broken browsers
1611                         $m = [];
1612                         if ( preg_match(
1613                                         '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1614                                         $_SERVER['HTTP_ACCEPT_ENCODING'],
1615                                         $m
1616                                 )
1617                         ) {
1618                                 if ( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1619                                         $result = false;
1620                                         return $result;
1621                                 }
1622                                 wfDebug( "wfClientAcceptsGzip: client accepts gzip.\n" );
1623                                 $result = true;
1624                         }
1625                 }
1626         }
1627         return $result;
1628 }
1629
1630 /**
1631  * Escapes the given text so that it may be output using addWikiText()
1632  * without any linking, formatting, etc. making its way through. This
1633  * is achieved by substituting certain characters with HTML entities.
1634  * As required by the callers, "<nowiki>" is not used.
1635  *
1636  * @param string $text Text to be escaped
1637  * @param-taint $text escapes_html
1638  * @return string
1639  */
1640 function wfEscapeWikiText( $text ) {
1641         global $wgEnableMagicLinks;
1642         static $repl = null, $repl2 = null;
1643         if ( $repl === null || defined( 'MW_PARSER_TEST' ) || defined( 'MW_PHPUNIT_TEST' ) ) {
1644                 // Tests depend upon being able to change $wgEnableMagicLinks, so don't cache
1645                 // in those situations
1646                 $repl = [
1647                         '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
1648                         '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
1649                         '{' => '&#123;', '|' => '&#124;', '}' => '&#125;', ';' => '&#59;',
1650                         "\n#" => "\n&#35;", "\r#" => "\r&#35;",
1651                         "\n*" => "\n&#42;", "\r*" => "\r&#42;",
1652                         "\n:" => "\n&#58;", "\r:" => "\r&#58;",
1653                         "\n " => "\n&#32;", "\r " => "\r&#32;",
1654                         "\n\n" => "\n&#10;", "\r\n" => "&#13;\n",
1655                         "\n\r" => "\n&#13;", "\r\r" => "\r&#13;",
1656                         "\n\t" => "\n&#9;", "\r\t" => "\r&#9;", // "\n\t\n" is treated like "\n\n"
1657                         "\n----" => "\n&#45;---", "\r----" => "\r&#45;---",
1658                         '__' => '_&#95;', '://' => '&#58;//',
1659                 ];
1660
1661                 $magicLinks = array_keys( array_filter( $wgEnableMagicLinks ) );
1662                 // We have to catch everything "\s" matches in PCRE
1663                 foreach ( $magicLinks as $magic ) {
1664                         $repl["$magic "] = "$magic&#32;";
1665                         $repl["$magic\t"] = "$magic&#9;";
1666                         $repl["$magic\r"] = "$magic&#13;";
1667                         $repl["$magic\n"] = "$magic&#10;";
1668                         $repl["$magic\f"] = "$magic&#12;";
1669                 }
1670
1671                 // And handle protocols that don't use "://"
1672                 global $wgUrlProtocols;
1673                 $repl2 = [];
1674                 foreach ( $wgUrlProtocols as $prot ) {
1675                         if ( substr( $prot, -1 ) === ':' ) {
1676                                 $repl2[] = preg_quote( substr( $prot, 0, -1 ), '/' );
1677                         }
1678                 }
1679                 $repl2 = $repl2 ? '/\b(' . implode( '|', $repl2 ) . '):/i' : '/^(?!)/';
1680         }
1681         $text = substr( strtr( "\n$text", $repl ), 1 );
1682         $text = preg_replace( $repl2, '$1&#58;', $text );
1683         return $text;
1684 }
1685
1686 /**
1687  * Sets dest to source and returns the original value of dest
1688  * If source is NULL, it just returns the value, it doesn't set the variable
1689  * If force is true, it will set the value even if source is NULL
1690  *
1691  * @param mixed &$dest
1692  * @param mixed $source
1693  * @param bool $force
1694  * @return mixed
1695  */
1696 function wfSetVar( &$dest, $source, $force = false ) {
1697         $temp = $dest;
1698         if ( !is_null( $source ) || $force ) {
1699                 $dest = $source;
1700         }
1701         return $temp;
1702 }
1703
1704 /**
1705  * As for wfSetVar except setting a bit
1706  *
1707  * @param int &$dest
1708  * @param int $bit
1709  * @param bool $state
1710  *
1711  * @return bool
1712  */
1713 function wfSetBit( &$dest, $bit, $state = true ) {
1714         $temp = (bool)( $dest & $bit );
1715         if ( !is_null( $state ) ) {
1716                 if ( $state ) {
1717                         $dest |= $bit;
1718                 } else {
1719                         $dest &= ~$bit;
1720                 }
1721         }
1722         return $temp;
1723 }
1724
1725 /**
1726  * A wrapper around the PHP function var_export().
1727  * Either print it or add it to the regular output ($wgOut).
1728  *
1729  * @param mixed $var A PHP variable to dump.
1730  */
1731 function wfVarDump( $var ) {
1732         global $wgOut;
1733         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
1734         if ( headers_sent() || !isset( $wgOut ) || !is_object( $wgOut ) ) {
1735                 print $s;
1736         } else {
1737                 $wgOut->addHTML( $s );
1738         }
1739 }
1740
1741 /**
1742  * Provide a simple HTTP error.
1743  *
1744  * @param int|string $code
1745  * @param string $label
1746  * @param string $desc
1747  */
1748 function wfHttpError( $code, $label, $desc ) {
1749         global $wgOut;
1750         HttpStatus::header( $code );
1751         if ( $wgOut ) {
1752                 $wgOut->disable();
1753                 $wgOut->sendCacheControl();
1754         }
1755
1756         MediaWiki\HeaderCallback::warnIfHeadersSent();
1757         header( 'Content-type: text/html; charset=utf-8' );
1758         print '<!DOCTYPE html>' .
1759                 '<html><head><title>' .
1760                 htmlspecialchars( $label ) .
1761                 '</title></head><body><h1>' .
1762                 htmlspecialchars( $label ) .
1763                 '</h1><p>' .
1764                 nl2br( htmlspecialchars( $desc ) ) .
1765                 "</p></body></html>\n";
1766 }
1767
1768 /**
1769  * Clear away any user-level output buffers, discarding contents.
1770  *
1771  * Suitable for 'starting afresh', for instance when streaming
1772  * relatively large amounts of data without buffering, or wanting to
1773  * output image files without ob_gzhandler's compression.
1774  *
1775  * The optional $resetGzipEncoding parameter controls suppression of
1776  * the Content-Encoding header sent by ob_gzhandler; by default it
1777  * is left. See comments for wfClearOutputBuffers() for why it would
1778  * be used.
1779  *
1780  * Note that some PHP configuration options may add output buffer
1781  * layers which cannot be removed; these are left in place.
1782  *
1783  * @param bool $resetGzipEncoding
1784  */
1785 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
1786         if ( $resetGzipEncoding ) {
1787                 // Suppress Content-Encoding and Content-Length
1788                 // headers from OutputHandler::handle.
1789                 global $wgDisableOutputCompression;
1790                 $wgDisableOutputCompression = true;
1791         }
1792         while ( $status = ob_get_status() ) {
1793                 if ( isset( $status['flags'] ) ) {
1794                         $flags = PHP_OUTPUT_HANDLER_CLEANABLE | PHP_OUTPUT_HANDLER_REMOVABLE;
1795                         $deleteable = ( $status['flags'] & $flags ) === $flags;
1796                 } elseif ( isset( $status['del'] ) ) {
1797                         $deleteable = $status['del'];
1798                 } else {
1799                         // Guess that any PHP-internal setting can't be removed.
1800                         $deleteable = $status['type'] !== 0; /* PHP_OUTPUT_HANDLER_INTERNAL */
1801                 }
1802                 if ( !$deleteable ) {
1803                         // Give up, and hope the result doesn't break
1804                         // output behavior.
1805                         break;
1806                 }
1807                 if ( $status['name'] === 'MediaWikiTestCase::wfResetOutputBuffersBarrier' ) {
1808                         // Unit testing barrier to prevent this function from breaking PHPUnit.
1809                         break;
1810                 }
1811                 if ( !ob_end_clean() ) {
1812                         // Could not remove output buffer handler; abort now
1813                         // to avoid getting in some kind of infinite loop.
1814                         break;
1815                 }
1816                 if ( $resetGzipEncoding ) {
1817                         if ( $status['name'] == 'ob_gzhandler' ) {
1818                                 // Reset the 'Content-Encoding' field set by this handler
1819                                 // so we can start fresh.
1820                                 header_remove( 'Content-Encoding' );
1821                                 break;
1822                         }
1823                 }
1824         }
1825 }
1826
1827 /**
1828  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
1829  *
1830  * Clear away output buffers, but keep the Content-Encoding header
1831  * produced by ob_gzhandler, if any.
1832  *
1833  * This should be used for HTTP 304 responses, where you need to
1834  * preserve the Content-Encoding header of the real result, but
1835  * also need to suppress the output of ob_gzhandler to keep to spec
1836  * and avoid breaking Firefox in rare cases where the headers and
1837  * body are broken over two packets.
1838  */
1839 function wfClearOutputBuffers() {
1840         wfResetOutputBuffers( false );
1841 }
1842
1843 /**
1844  * Converts an Accept-* header into an array mapping string values to quality
1845  * factors
1846  *
1847  * @param string $accept
1848  * @param string $def Default
1849  * @return float[] Associative array of string => float pairs
1850  */
1851 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
1852         # No arg means accept anything (per HTTP spec)
1853         if ( !$accept ) {
1854                 return [ $def => 1.0 ];
1855         }
1856
1857         $prefs = [];
1858
1859         $parts = explode( ',', $accept );
1860
1861         foreach ( $parts as $part ) {
1862                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
1863                 $values = explode( ';', trim( $part ) );
1864                 $match = [];
1865                 if ( count( $values ) == 1 ) {
1866                         $prefs[$values[0]] = 1.0;
1867                 } elseif ( preg_match( '/q\s*=\s*(\d*\.\d+)/', $values[1], $match ) ) {
1868                         $prefs[$values[0]] = floatval( $match[1] );
1869                 }
1870         }
1871
1872         return $prefs;
1873 }
1874
1875 /**
1876  * Checks if a given MIME type matches any of the keys in the given
1877  * array. Basic wildcards are accepted in the array keys.
1878  *
1879  * Returns the matching MIME type (or wildcard) if a match, otherwise
1880  * NULL if no match.
1881  *
1882  * @param string $type
1883  * @param array $avail
1884  * @return string
1885  * @private
1886  */
1887 function mimeTypeMatch( $type, $avail ) {
1888         if ( array_key_exists( $type, $avail ) ) {
1889                 return $type;
1890         } else {
1891                 $mainType = explode( '/', $type )[0];
1892                 if ( array_key_exists( "$mainType/*", $avail ) ) {
1893                         return "$mainType/*";
1894                 } elseif ( array_key_exists( '*/*', $avail ) ) {
1895                         return '*/*';
1896                 } else {
1897                         return null;
1898                 }
1899         }
1900 }
1901
1902 /**
1903  * Returns the 'best' match between a client's requested internet media types
1904  * and the server's list of available types. Each list should be an associative
1905  * array of type to preference (preference is a float between 0.0 and 1.0).
1906  * Wildcards in the types are acceptable.
1907  *
1908  * @param array $cprefs Client's acceptable type list
1909  * @param array $sprefs Server's offered types
1910  * @return string
1911  *
1912  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
1913  * XXX: generalize to negotiate other stuff
1914  */
1915 function wfNegotiateType( $cprefs, $sprefs ) {
1916         $combine = [];
1917
1918         foreach ( array_keys( $sprefs ) as $type ) {
1919                 $subType = explode( '/', $type )[1];
1920                 if ( $subType != '*' ) {
1921                         $ckey = mimeTypeMatch( $type, $cprefs );
1922                         if ( $ckey ) {
1923                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
1924                         }
1925                 }
1926         }
1927
1928         foreach ( array_keys( $cprefs ) as $type ) {
1929                 $subType = explode( '/', $type )[1];
1930                 if ( $subType != '*' && !array_key_exists( $type, $sprefs ) ) {
1931                         $skey = mimeTypeMatch( $type, $sprefs );
1932                         if ( $skey ) {
1933                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
1934                         }
1935                 }
1936         }
1937
1938         $bestq = 0;
1939         $besttype = null;
1940
1941         foreach ( array_keys( $combine ) as $type ) {
1942                 if ( $combine[$type] > $bestq ) {
1943                         $besttype = $type;
1944                         $bestq = $combine[$type];
1945                 }
1946         }
1947
1948         return $besttype;
1949 }
1950
1951 /**
1952  * Reference-counted warning suppression
1953  *
1954  * @deprecated since 1.26, use Wikimedia\suppressWarnings() directly
1955  * @param bool $end
1956  */
1957 function wfSuppressWarnings( $end = false ) {
1958         Wikimedia\suppressWarnings( $end );
1959 }
1960
1961 /**
1962  * @deprecated since 1.26, use Wikimedia\restoreWarnings() directly
1963  * Restore error level to previous value
1964  */
1965 function wfRestoreWarnings() {
1966         Wikimedia\restoreWarnings();
1967 }
1968
1969 /**
1970  * Get a timestamp string in one of various formats
1971  *
1972  * @param mixed $outputtype A timestamp in one of the supported formats, the
1973  *   function will autodetect which format is supplied and act accordingly.
1974  * @param mixed $ts Optional timestamp to convert, default 0 for the current time
1975  * @return string|bool String / false The same date in the format specified in $outputtype or false
1976  */
1977 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
1978         $ret = MWTimestamp::convert( $outputtype, $ts );
1979         if ( $ret === false ) {
1980                 wfDebug( "wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n" );
1981         }
1982         return $ret;
1983 }
1984
1985 /**
1986  * Return a formatted timestamp, or null if input is null.
1987  * For dealing with nullable timestamp columns in the database.
1988  *
1989  * @param int $outputtype
1990  * @param string|null $ts
1991  * @return string
1992  */
1993 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
1994         if ( is_null( $ts ) ) {
1995                 return null;
1996         } else {
1997                 return wfTimestamp( $outputtype, $ts );
1998         }
1999 }
2000
2001 /**
2002  * Convenience function; returns MediaWiki timestamp for the present time.
2003  *
2004  * @return string
2005  */
2006 function wfTimestampNow() {
2007         # return NOW
2008         return MWTimestamp::now( TS_MW );
2009 }
2010
2011 /**
2012  * Check if the operating system is Windows
2013  *
2014  * @return bool True if it's Windows, false otherwise.
2015  */
2016 function wfIsWindows() {
2017         static $isWindows = null;
2018         if ( $isWindows === null ) {
2019                 $isWindows = strtoupper( substr( PHP_OS, 0, 3 ) ) === 'WIN';
2020         }
2021         return $isWindows;
2022 }
2023
2024 /**
2025  * Check if we are running under HHVM
2026  *
2027  * @return bool
2028  */
2029 function wfIsHHVM() {
2030         return defined( 'HHVM_VERSION' );
2031 }
2032
2033 /**
2034  * Check if we are running from the commandline
2035  *
2036  * @since 1.31
2037  * @return bool
2038  */
2039 function wfIsCLI() {
2040         return PHP_SAPI === 'cli' || PHP_SAPI === 'phpdbg';
2041 }
2042
2043 /**
2044  * Tries to get the system directory for temporary files. First
2045  * $wgTmpDirectory is checked, and then the TMPDIR, TMP, and TEMP
2046  * environment variables are then checked in sequence, then
2047  * sys_get_temp_dir(), then upload_tmp_dir from php.ini.
2048  *
2049  * NOTE: When possible, use instead the tmpfile() function to create
2050  * temporary files to avoid race conditions on file creation, etc.
2051  *
2052  * @return string
2053  */
2054 function wfTempDir() {
2055         global $wgTmpDirectory;
2056
2057         if ( $wgTmpDirectory !== false ) {
2058                 return $wgTmpDirectory;
2059         }
2060
2061         return TempFSFile::getUsableTempDirectory();
2062 }
2063
2064 /**
2065  * Make directory, and make all parent directories if they don't exist
2066  *
2067  * @param string $dir Full path to directory to create
2068  * @param int|null $mode Chmod value to use, default is $wgDirectoryMode
2069  * @param string|null $caller Optional caller param for debugging.
2070  * @throws MWException
2071  * @return bool
2072  */
2073 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2074         global $wgDirectoryMode;
2075
2076         if ( FileBackend::isStoragePath( $dir ) ) { // sanity
2077                 throw new MWException( __FUNCTION__ . " given storage path '$dir'." );
2078         }
2079
2080         if ( !is_null( $caller ) ) {
2081                 wfDebug( "$caller: called wfMkdirParents($dir)\n" );
2082         }
2083
2084         if ( strval( $dir ) === '' || is_dir( $dir ) ) {
2085                 return true;
2086         }
2087
2088         $dir = str_replace( [ '\\', '/' ], DIRECTORY_SEPARATOR, $dir );
2089
2090         if ( is_null( $mode ) ) {
2091                 $mode = $wgDirectoryMode;
2092         }
2093
2094         // Turn off the normal warning, we're doing our own below
2095         Wikimedia\suppressWarnings();
2096         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2097         Wikimedia\restoreWarnings();
2098
2099         if ( !$ok ) {
2100                 // directory may have been created on another request since we last checked
2101                 if ( is_dir( $dir ) ) {
2102                         return true;
2103                 }
2104
2105                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2106                 wfLogWarning( sprintf( "failed to mkdir \"%s\" mode 0%o", $dir, $mode ) );
2107         }
2108         return $ok;
2109 }
2110
2111 /**
2112  * Remove a directory and all its content.
2113  * Does not hide error.
2114  * @param string $dir
2115  */
2116 function wfRecursiveRemoveDir( $dir ) {
2117         wfDebug( __FUNCTION__ . "( $dir )\n" );
2118         // taken from https://secure.php.net/manual/en/function.rmdir.php#98622
2119         if ( is_dir( $dir ) ) {
2120                 $objects = scandir( $dir );
2121                 foreach ( $objects as $object ) {
2122                         if ( $object != "." && $object != ".." ) {
2123                                 if ( filetype( $dir . '/' . $object ) == "dir" ) {
2124                                         wfRecursiveRemoveDir( $dir . '/' . $object );
2125                                 } else {
2126                                         unlink( $dir . '/' . $object );
2127                                 }
2128                         }
2129                 }
2130                 reset( $objects );
2131                 rmdir( $dir );
2132         }
2133 }
2134
2135 /**
2136  * @param int $nr The number to format
2137  * @param int $acc The number of digits after the decimal point, default 2
2138  * @param bool $round Whether or not to round the value, default true
2139  * @return string
2140  */
2141 function wfPercent( $nr, $acc = 2, $round = true ) {
2142         $ret = sprintf( "%.${acc}f", $nr );
2143         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2144 }
2145
2146 /**
2147  * Safety wrapper around ini_get() for boolean settings.
2148  * The values returned from ini_get() are pre-normalized for settings
2149  * set via php.ini or php_flag/php_admin_flag... but *not*
2150  * for those set via php_value/php_admin_value.
2151  *
2152  * It's fairly common for people to use php_value instead of php_flag,
2153  * which can leave you with an 'off' setting giving a false positive
2154  * for code that just takes the ini_get() return value as a boolean.
2155  *
2156  * To make things extra interesting, setting via php_value accepts
2157  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2158  * Unrecognized values go false... again opposite PHP's own coercion
2159  * from string to bool.
2160  *
2161  * Luckily, 'properly' set settings will always come back as '0' or '1',
2162  * so we only have to worry about them and the 'improper' settings.
2163  *
2164  * I frickin' hate PHP... :P
2165  *
2166  * @param string $setting
2167  * @return bool
2168  */
2169 function wfIniGetBool( $setting ) {
2170         return wfStringToBool( ini_get( $setting ) );
2171 }
2172
2173 /**
2174  * Convert string value to boolean, when the following are interpreted as true:
2175  * - on
2176  * - true
2177  * - yes
2178  * - Any number, except 0
2179  * All other strings are interpreted as false.
2180  *
2181  * @param string $val
2182  * @return bool
2183  * @since 1.31
2184  */
2185 function wfStringToBool( $val ) {
2186         $val = strtolower( $val );
2187         // 'on' and 'true' can't have whitespace around them, but '1' can.
2188         return $val == 'on'
2189                 || $val == 'true'
2190                 || $val == 'yes'
2191                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2192 }
2193
2194 /**
2195  * Version of escapeshellarg() that works better on Windows.
2196  *
2197  * Originally, this fixed the incorrect use of single quotes on Windows
2198  * (https://bugs.php.net/bug.php?id=26285) and the locale problems on Linux in
2199  * PHP 5.2.6+ (bug backported to earlier distro releases of PHP).
2200  *
2201  * @param string $args,... strings to escape and glue together,
2202  *  or a single array of strings parameter
2203  * @return string
2204  * @deprecated since 1.30 use MediaWiki\Shell::escape()
2205  */
2206 function wfEscapeShellArg( /*...*/ ) {
2207         return Shell::escape( ...func_get_args() );
2208 }
2209
2210 /**
2211  * Execute a shell command, with time and memory limits mirrored from the PHP
2212  * configuration if supported.
2213  *
2214  * @param string|string[] $cmd If string, a properly shell-escaped command line,
2215  *   or an array of unescaped arguments, in which case each value will be escaped
2216  *   Example:   [ 'convert', '-font', 'font name' ] would produce "'convert' '-font' 'font name'"
2217  * @param null|mixed &$retval Optional, will receive the program's exit code.
2218  *   (non-zero is usually failure). If there is an error from
2219  *   read, select, or proc_open(), this will be set to -1.
2220  * @param array $environ Optional environment variables which should be
2221  *   added to the executed command environment.
2222  * @param array $limits Optional array with limits(filesize, memory, time, walltime)
2223  *   this overwrites the global wgMaxShell* limits.
2224  * @param array $options Array of options:
2225  *   - duplicateStderr: Set this to true to duplicate stderr to stdout,
2226  *     including errors from limit.sh
2227  *   - profileMethod: By default this function will profile based on the calling
2228  *     method. Set this to a string for an alternative method to profile from
2229  *
2230  * @return string Collected stdout as a string
2231  * @deprecated since 1.30 use class MediaWiki\Shell\Shell
2232  */
2233 function wfShellExec( $cmd, &$retval = null, $environ = [],
2234         $limits = [], $options = []
2235 ) {
2236         if ( Shell::isDisabled() ) {
2237                 $retval = 1;
2238                 // Backwards compatibility be upon us...
2239                 return 'Unable to run external programs, proc_open() is disabled.';
2240         }
2241
2242         if ( is_array( $cmd ) ) {
2243                 $cmd = Shell::escape( $cmd );
2244         }
2245
2246         $includeStderr = isset( $options['duplicateStderr'] ) && $options['duplicateStderr'];
2247         $profileMethod = $options['profileMethod'] ?? wfGetCaller();
2248
2249         try {
2250                 $result = Shell::command( [] )
2251                         ->unsafeParams( (array)$cmd )
2252                         ->environment( $environ )
2253                         ->limits( $limits )
2254                         ->includeStderr( $includeStderr )
2255                         ->profileMethod( $profileMethod )
2256                         // For b/c
2257                         ->restrict( Shell::RESTRICT_NONE )
2258                         ->execute();
2259         } catch ( ProcOpenError $ex ) {
2260                 $retval = -1;
2261                 return '';
2262         }
2263
2264         $retval = $result->getExitCode();
2265
2266         return $result->getStdout();
2267 }
2268
2269 /**
2270  * Execute a shell command, returning both stdout and stderr. Convenience
2271  * function, as all the arguments to wfShellExec can become unwieldy.
2272  *
2273  * @note This also includes errors from limit.sh, e.g. if $wgMaxShellFileSize is exceeded.
2274  * @param string|string[] $cmd If string, a properly shell-escaped command line,
2275  *   or an array of unescaped arguments, in which case each value will be escaped
2276  *   Example:   [ 'convert', '-font', 'font name' ] would produce "'convert' '-font' 'font name'"
2277  * @param null|mixed &$retval Optional, will receive the program's exit code.
2278  *   (non-zero is usually failure)
2279  * @param array $environ Optional environment variables which should be
2280  *   added to the executed command environment.
2281  * @param array $limits Optional array with limits(filesize, memory, time, walltime)
2282  *   this overwrites the global wgMaxShell* limits.
2283  * @return string Collected stdout and stderr as a string
2284  * @deprecated since 1.30 use class MediaWiki\Shell\Shell
2285  */
2286 function wfShellExecWithStderr( $cmd, &$retval = null, $environ = [], $limits = [] ) {
2287         return wfShellExec( $cmd, $retval, $environ, $limits,
2288                 [ 'duplicateStderr' => true, 'profileMethod' => wfGetCaller() ] );
2289 }
2290
2291 /**
2292  * Generate a shell-escaped command line string to run a MediaWiki cli script.
2293  * Note that $parameters should be a flat array and an option with an argument
2294  * should consist of two consecutive items in the array (do not use "--option value").
2295  *
2296  * @deprecated since 1.31, use Shell::makeScriptCommand()
2297  *
2298  * @param string $script MediaWiki cli script path
2299  * @param array $parameters Arguments and options to the script
2300  * @param array $options Associative array of options:
2301  *     'php': The path to the php executable
2302  *     'wrapper': Path to a PHP wrapper to handle the maintenance script
2303  * @return string
2304  */
2305 function wfShellWikiCmd( $script, array $parameters = [], array $options = [] ) {
2306         global $wgPhpCli;
2307         // Give site config file a chance to run the script in a wrapper.
2308         // The caller may likely want to call wfBasename() on $script.
2309         Hooks::run( 'wfShellWikiCmd', [ &$script, &$parameters, &$options ] );
2310         $cmd = [ $options['php'] ?? $wgPhpCli ];
2311         if ( isset( $options['wrapper'] ) ) {
2312                 $cmd[] = $options['wrapper'];
2313         }
2314         $cmd[] = $script;
2315         // Escape each parameter for shell
2316         return Shell::escape( array_merge( $cmd, $parameters ) );
2317 }
2318
2319 /**
2320  * wfMerge attempts to merge differences between three texts.
2321  * Returns true for a clean merge and false for failure or a conflict.
2322  *
2323  * @param string $old
2324  * @param string $mine
2325  * @param string $yours
2326  * @param string &$result
2327  * @param string|null &$mergeAttemptResult
2328  * @return bool
2329  */
2330 function wfMerge( $old, $mine, $yours, &$result, &$mergeAttemptResult = null ) {
2331         global $wgDiff3;
2332
2333         # This check may also protect against code injection in
2334         # case of broken installations.
2335         Wikimedia\suppressWarnings();
2336         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
2337         Wikimedia\restoreWarnings();
2338
2339         if ( !$haveDiff3 ) {
2340                 wfDebug( "diff3 not found\n" );
2341                 return false;
2342         }
2343
2344         # Make temporary files
2345         $td = wfTempDir();
2346         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
2347         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
2348         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
2349
2350         # NOTE: diff3 issues a warning to stderr if any of the files does not end with
2351         #       a newline character. To avoid this, we normalize the trailing whitespace before
2352         #       creating the diff.
2353
2354         fwrite( $oldtextFile, rtrim( $old ) . "\n" );
2355         fclose( $oldtextFile );
2356         fwrite( $mytextFile, rtrim( $mine ) . "\n" );
2357         fclose( $mytextFile );
2358         fwrite( $yourtextFile, rtrim( $yours ) . "\n" );
2359         fclose( $yourtextFile );
2360
2361         # Check for a conflict
2362         $cmd = Shell::escape( $wgDiff3, '-a', '--overlap-only', $mytextName,
2363                 $oldtextName, $yourtextName );
2364         $handle = popen( $cmd, 'r' );
2365
2366         $mergeAttemptResult = '';
2367         do {
2368                 $data = fread( $handle, 8192 );
2369                 if ( strlen( $data ) == 0 ) {
2370                         break;
2371                 }
2372                 $mergeAttemptResult .= $data;
2373         } while ( true );
2374         pclose( $handle );
2375
2376         $conflict = $mergeAttemptResult !== '';
2377
2378         # Merge differences
2379         $cmd = Shell::escape( $wgDiff3, '-a', '-e', '--merge', $mytextName,
2380                 $oldtextName, $yourtextName );
2381         $handle = popen( $cmd, 'r' );
2382         $result = '';
2383         do {
2384                 $data = fread( $handle, 8192 );
2385                 if ( strlen( $data ) == 0 ) {
2386                         break;
2387                 }
2388                 $result .= $data;
2389         } while ( true );
2390         pclose( $handle );
2391         unlink( $mytextName );
2392         unlink( $oldtextName );
2393         unlink( $yourtextName );
2394
2395         if ( $result === '' && $old !== '' && !$conflict ) {
2396                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
2397                 $conflict = true;
2398         }
2399         return !$conflict;
2400 }
2401
2402 /**
2403  * Returns unified plain-text diff of two texts.
2404  * "Useful" for machine processing of diffs.
2405  *
2406  * @deprecated since 1.25, use DiffEngine/UnifiedDiffFormatter directly
2407  *
2408  * @param string $before The text before the changes.
2409  * @param string $after The text after the changes.
2410  * @param string $params Command-line options for the diff command.
2411  * @return string Unified diff of $before and $after
2412  */
2413 function wfDiff( $before, $after, $params = '-u' ) {
2414         if ( $before == $after ) {
2415                 return '';
2416         }
2417
2418         global $wgDiff;
2419         Wikimedia\suppressWarnings();
2420         $haveDiff = $wgDiff && file_exists( $wgDiff );
2421         Wikimedia\restoreWarnings();
2422
2423         # This check may also protect against code injection in
2424         # case of broken installations.
2425         if ( !$haveDiff ) {
2426                 wfDebug( "diff executable not found\n" );
2427                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
2428                 $format = new UnifiedDiffFormatter();
2429                 return $format->format( $diffs );
2430         }
2431
2432         # Make temporary files
2433         $td = wfTempDir();
2434         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
2435         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
2436
2437         fwrite( $oldtextFile, $before );
2438         fclose( $oldtextFile );
2439         fwrite( $newtextFile, $after );
2440         fclose( $newtextFile );
2441
2442         // Get the diff of the two files
2443         $cmd = "$wgDiff " . $params . ' ' . Shell::escape( $oldtextName, $newtextName );
2444
2445         $h = popen( $cmd, 'r' );
2446         if ( !$h ) {
2447                 unlink( $oldtextName );
2448                 unlink( $newtextName );
2449                 throw new Exception( __METHOD__ . '(): popen() failed' );
2450         }
2451
2452         $diff = '';
2453
2454         do {
2455                 $data = fread( $h, 8192 );
2456                 if ( strlen( $data ) == 0 ) {
2457                         break;
2458                 }
2459                 $diff .= $data;
2460         } while ( true );
2461
2462         // Clean up
2463         pclose( $h );
2464         unlink( $oldtextName );
2465         unlink( $newtextName );
2466
2467         // Kill the --- and +++ lines. They're not useful.
2468         $diff_lines = explode( "\n", $diff );
2469         if ( isset( $diff_lines[0] ) && strpos( $diff_lines[0], '---' ) === 0 ) {
2470                 unset( $diff_lines[0] );
2471         }
2472         if ( isset( $diff_lines[1] ) && strpos( $diff_lines[1], '+++' ) === 0 ) {
2473                 unset( $diff_lines[1] );
2474         }
2475
2476         $diff = implode( "\n", $diff_lines );
2477
2478         return $diff;
2479 }
2480
2481 /**
2482  * This function works like "use VERSION" in Perl, the program will die with a
2483  * backtrace if the current version of PHP is less than the version provided
2484  *
2485  * This is useful for extensions which due to their nature are not kept in sync
2486  * with releases, and might depend on other versions of PHP than the main code
2487  *
2488  * Note: PHP might die due to parsing errors in some cases before it ever
2489  *       manages to call this function, such is life
2490  *
2491  * @see perldoc -f use
2492  *
2493  * @param string|int|float $req_ver The version to check, can be a string, an integer, or a float
2494  *
2495  * @deprecated since 1.30
2496  *
2497  * @throws MWException
2498  */
2499 function wfUsePHP( $req_ver ) {
2500         wfDeprecated( __FUNCTION__, '1.30' );
2501         $php_ver = PHP_VERSION;
2502
2503         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
2504                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
2505         }
2506 }
2507
2508 /**
2509  * This function works like "use VERSION" in Perl except it checks the version
2510  * of MediaWiki, the program will die with a backtrace if the current version
2511  * of MediaWiki is less than the version provided.
2512  *
2513  * This is useful for extensions which due to their nature are not kept in sync
2514  * with releases
2515  *
2516  * Note: Due to the behavior of PHP's version_compare() which is used in this
2517  * function, if you want to allow the 'wmf' development versions add a 'c' (or
2518  * any single letter other than 'a', 'b' or 'p') as a post-fix to your
2519  * targeted version number. For example if you wanted to allow any variation
2520  * of 1.22 use `wfUseMW( '1.22c' )`. Using an 'a' or 'b' instead of 'c' will
2521  * not result in the same comparison due to the internal logic of
2522  * version_compare().
2523  *
2524  * @see perldoc -f use
2525  *
2526  * @deprecated since 1.26, use the "requires" property of extension.json
2527  * @param string|int|float $req_ver The version to check, can be a string, an integer, or a float
2528  * @throws MWException
2529  */
2530 function wfUseMW( $req_ver ) {
2531         global $wgVersion;
2532
2533         wfDeprecated( __FUNCTION__, '1.26' );
2534
2535         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
2536                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
2537         }
2538 }
2539
2540 /**
2541  * Return the final portion of a pathname.
2542  * Reimplemented because PHP5's "basename()" is buggy with multibyte text.
2543  * https://bugs.php.net/bug.php?id=33898
2544  *
2545  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
2546  * We'll consider it so always, as we don't want '\s' in our Unix paths either.
2547  *
2548  * @param string $path
2549  * @param string $suffix String to remove if present
2550  * @return string
2551  */
2552 function wfBaseName( $path, $suffix = '' ) {
2553         if ( $suffix == '' ) {
2554                 $encSuffix = '';
2555         } else {
2556                 $encSuffix = '(?:' . preg_quote( $suffix, '#' ) . ')?';
2557         }
2558
2559         $matches = [];
2560         if ( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2561                 return $matches[1];
2562         } else {
2563                 return '';
2564         }
2565 }
2566
2567 /**
2568  * Generate a relative path name to the given file.
2569  * May explode on non-matching case-insensitive paths,
2570  * funky symlinks, etc.
2571  *
2572  * @param string $path Absolute destination path including target filename
2573  * @param string $from Absolute source path, directory only
2574  * @return string
2575  */
2576 function wfRelativePath( $path, $from ) {
2577         // Normalize mixed input on Windows...
2578         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2579         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2580
2581         // Trim trailing slashes -- fix for drive root
2582         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2583         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2584
2585         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2586         $against = explode( DIRECTORY_SEPARATOR, $from );
2587
2588         if ( $pieces[0] !== $against[0] ) {
2589                 // Non-matching Windows drive letters?
2590                 // Return a full path.
2591                 return $path;
2592         }
2593
2594         // Trim off common prefix
2595         while ( count( $pieces ) && count( $against )
2596                 && $pieces[0] == $against[0] ) {
2597                 array_shift( $pieces );
2598                 array_shift( $against );
2599         }
2600
2601         // relative dots to bump us to the parent
2602         while ( count( $against ) ) {
2603                 array_unshift( $pieces, '..' );
2604                 array_shift( $against );
2605         }
2606
2607         array_push( $pieces, wfBaseName( $path ) );
2608
2609         return implode( DIRECTORY_SEPARATOR, $pieces );
2610 }
2611
2612 /**
2613  * Reset the session id
2614  *
2615  * @deprecated since 1.27, use MediaWiki\Session\SessionManager instead
2616  * @since 1.22
2617  */
2618 function wfResetSessionID() {
2619         wfDeprecated( __FUNCTION__, '1.27' );
2620         $session = SessionManager::getGlobalSession();
2621         $delay = $session->delaySave();
2622
2623         $session->resetId();
2624
2625         // Make sure a session is started, since that's what the old
2626         // wfResetSessionID() did.
2627         if ( session_id() !== $session->getId() ) {
2628                 wfSetupSession( $session->getId() );
2629         }
2630
2631         ScopedCallback::consume( $delay );
2632 }
2633
2634 /**
2635  * Initialise php session
2636  *
2637  * @deprecated since 1.27, use MediaWiki\Session\SessionManager instead.
2638  *  Generally, "using" SessionManager will be calling ->getSessionById() or
2639  *  ::getGlobalSession() (depending on whether you were passing $sessionId
2640  *  here), then calling $session->persist().
2641  * @param bool|string $sessionId
2642  */
2643 function wfSetupSession( $sessionId = false ) {
2644         wfDeprecated( __FUNCTION__, '1.27' );
2645
2646         if ( $sessionId ) {
2647                 session_id( $sessionId );
2648         }
2649
2650         $session = SessionManager::getGlobalSession();
2651         $session->persist();
2652
2653         if ( session_id() !== $session->getId() ) {
2654                 session_id( $session->getId() );
2655         }
2656         Wikimedia\quietCall( 'session_start' );
2657 }
2658
2659 /**
2660  * Get an object from the precompiled serialized directory
2661  *
2662  * @param string $name
2663  * @return mixed The variable on success, false on failure
2664  */
2665 function wfGetPrecompiledData( $name ) {
2666         global $IP;
2667
2668         $file = "$IP/serialized/$name";
2669         if ( file_exists( $file ) ) {
2670                 $blob = file_get_contents( $file );
2671                 if ( $blob ) {
2672                         return unserialize( $blob );
2673                 }
2674         }
2675         return false;
2676 }
2677
2678 /**
2679  * @deprecated since 1.32 use StaticArrayWriter instead
2680  * @since 1.32
2681  * @param string[] $data Array with string keys/values to export
2682  * @param string $header
2683  * @return string PHP code
2684  */
2685 function wfMakeStaticArrayFile( array $data, $header = 'Automatically generated' ) {
2686         return ( new StaticArrayWriter() )->create( $data, $header );
2687 }
2688
2689 /**
2690  * Make a cache key for the local wiki.
2691  *
2692  * @deprecated since 1.30 Call makeKey on a BagOStuff instance
2693  * @param string $args,...
2694  * @return string
2695  */
2696 function wfMemcKey( /*...*/ ) {
2697         return ObjectCache::getLocalClusterInstance()->makeKey( ...func_get_args() );
2698 }
2699
2700 /**
2701  * Make a cache key for a foreign DB.
2702  *
2703  * Must match what wfMemcKey() would produce in context of the foreign wiki.
2704  *
2705  * @param string $db
2706  * @param string $prefix
2707  * @param string $args,...
2708  * @return string
2709  */
2710 function wfForeignMemcKey( $db, $prefix /*...*/ ) {
2711         $args = array_slice( func_get_args(), 2 );
2712         $keyspace = $prefix ? "$db-$prefix" : $db;
2713         return ObjectCache::getLocalClusterInstance()->makeKeyInternal( $keyspace, $args );
2714 }
2715
2716 /**
2717  * Make a cache key with database-agnostic prefix.
2718  *
2719  * Doesn't have a wiki-specific namespace. Uses a generic 'global' prefix
2720  * instead. Must have a prefix as otherwise keys that use a database name
2721  * in the first segment will clash with wfMemcKey/wfForeignMemcKey.
2722  *
2723  * @deprecated since 1.30 Call makeGlobalKey on a BagOStuff instance
2724  * @since 1.26
2725  * @param string $args,...
2726  * @return string
2727  */
2728 function wfGlobalCacheKey( /*...*/ ) {
2729         return ObjectCache::getLocalClusterInstance()->makeGlobalKey( ...func_get_args() );
2730 }
2731
2732 /**
2733  * Get an ASCII string identifying this wiki
2734  * This is used as a prefix in memcached keys
2735  *
2736  * @return string
2737  */
2738 function wfWikiID() {
2739         global $wgDBprefix, $wgDBname;
2740         if ( $wgDBprefix ) {
2741                 return "$wgDBname-$wgDBprefix";
2742         } else {
2743                 return $wgDBname;
2744         }
2745 }
2746
2747 /**
2748  * Split a wiki ID into DB name and table prefix
2749  *
2750  * @param string $wiki
2751  *
2752  * @return array
2753  */
2754 function wfSplitWikiID( $wiki ) {
2755         $bits = explode( '-', $wiki, 2 );
2756         if ( count( $bits ) < 2 ) {
2757                 $bits[] = '';
2758         }
2759         return $bits;
2760 }
2761
2762 /**
2763  * Get a Database object.
2764  *
2765  * @param int $db Index of the connection to get. May be DB_MASTER for the
2766  *            master (for write queries), DB_REPLICA for potentially lagged read
2767  *            queries, or an integer >= 0 for a particular server.
2768  *
2769  * @param string|string[] $groups Query groups. An array of group names that this query
2770  *                belongs to. May contain a single string if the query is only
2771  *                in one group.
2772  *
2773  * @param string|bool $wiki The wiki ID, or false for the current wiki
2774  *
2775  * Note: multiple calls to wfGetDB(DB_REPLICA) during the course of one request
2776  * will always return the same object, unless the underlying connection or load
2777  * balancer is manually destroyed.
2778  *
2779  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
2780  * updater to ensure that a proper database is being updated.
2781  *
2782  * @todo Replace calls to wfGetDB with calls to LoadBalancer::getConnection()
2783  *       on an injected instance of LoadBalancer.
2784  *
2785  * @return \Wikimedia\Rdbms\Database
2786  */
2787 function wfGetDB( $db, $groups = [], $wiki = false ) {
2788         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
2789 }
2790
2791 /**
2792  * Get a load balancer object.
2793  *
2794  * @deprecated since 1.27, use MediaWikiServices::getDBLoadBalancer()
2795  *              or MediaWikiServices::getDBLoadBalancerFactory() instead.
2796  *
2797  * @param string|bool $wiki Wiki ID, or false for the current wiki
2798  * @return \Wikimedia\Rdbms\LoadBalancer
2799  */
2800 function wfGetLB( $wiki = false ) {
2801         if ( $wiki === false ) {
2802                 return MediaWikiServices::getInstance()->getDBLoadBalancer();
2803         } else {
2804                 $factory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
2805                 return $factory->getMainLB( $wiki );
2806         }
2807 }
2808
2809 /**
2810  * Get the load balancer factory object
2811  *
2812  * @deprecated since 1.27, use MediaWikiServices::getDBLoadBalancerFactory() instead.
2813  *
2814  * @return \Wikimedia\Rdbms\LBFactory
2815  */
2816 function wfGetLBFactory() {
2817         return MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
2818 }
2819
2820 /**
2821  * Find a file.
2822  * Shortcut for RepoGroup::singleton()->findFile()
2823  *
2824  * @param string|Title $title String or Title object
2825  * @param array $options Associative array of options (see RepoGroup::findFile)
2826  * @return File|bool File, or false if the file does not exist
2827  */
2828 function wfFindFile( $title, $options = [] ) {
2829         return RepoGroup::singleton()->findFile( $title, $options );
2830 }
2831
2832 /**
2833  * Get an object referring to a locally registered file.
2834  * Returns a valid placeholder object if the file does not exist.
2835  *
2836  * @param Title|string $title
2837  * @return LocalFile|null A File, or null if passed an invalid Title
2838  */
2839 function wfLocalFile( $title ) {
2840         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
2841 }
2842
2843 /**
2844  * Should low-performance queries be disabled?
2845  *
2846  * @return bool
2847  * @codeCoverageIgnore
2848  */
2849 function wfQueriesMustScale() {
2850         global $wgMiserMode;
2851         return $wgMiserMode
2852                 || ( SiteStats::pages() > 100000
2853                 && SiteStats::edits() > 1000000
2854                 && SiteStats::users() > 10000 );
2855 }
2856
2857 /**
2858  * Get the path to a specified script file, respecting file
2859  * extensions; this is a wrapper around $wgScriptPath etc.
2860  * except for 'index' and 'load' which use $wgScript/$wgLoadScript
2861  *
2862  * @param string $script Script filename, sans extension
2863  * @return string
2864  */
2865 function wfScript( $script = 'index' ) {
2866         global $wgScriptPath, $wgScript, $wgLoadScript;
2867         if ( $script === 'index' ) {
2868                 return $wgScript;
2869         } elseif ( $script === 'load' ) {
2870                 return $wgLoadScript;
2871         } else {
2872                 return "{$wgScriptPath}/{$script}.php";
2873         }
2874 }
2875
2876 /**
2877  * Get the script URL.
2878  *
2879  * @return string Script URL
2880  */
2881 function wfGetScriptUrl() {
2882         if ( isset( $_SERVER['SCRIPT_NAME'] ) ) {
2883                 /* as it was called, minus the query string.
2884                  *
2885                  * Some sites use Apache rewrite rules to handle subdomains,
2886                  * and have PHP set up in a weird way that causes PHP_SELF
2887                  * to contain the rewritten URL instead of the one that the
2888                  * outside world sees.
2889                  *
2890                  * If in this mode, use SCRIPT_URL instead, which mod_rewrite
2891                  * provides containing the "before" URL.
2892                  */
2893                 return $_SERVER['SCRIPT_NAME'];
2894         } else {
2895                 return $_SERVER['URL'];
2896         }
2897 }
2898
2899 /**
2900  * Convenience function converts boolean values into "true"
2901  * or "false" (string) values
2902  *
2903  * @param bool $value
2904  * @return string
2905  */
2906 function wfBoolToStr( $value ) {
2907         return $value ? 'true' : 'false';
2908 }
2909
2910 /**
2911  * Get a platform-independent path to the null file, e.g. /dev/null
2912  *
2913  * @return string
2914  */
2915 function wfGetNull() {
2916         return wfIsWindows() ? 'NUL' : '/dev/null';
2917 }
2918
2919 /**
2920  * Waits for the replica DBs to catch up to the master position
2921  *
2922  * Use this when updating very large numbers of rows, as in maintenance scripts,
2923  * to avoid causing too much lag. Of course, this is a no-op if there are no replica DBs.
2924  *
2925  * By default this waits on the main DB cluster of the current wiki.
2926  * If $cluster is set to "*" it will wait on all DB clusters, including
2927  * external ones. If the lag being waiting on is caused by the code that
2928  * does this check, it makes since to use $ifWritesSince, particularly if
2929  * cluster is "*", to avoid excess overhead.
2930  *
2931  * Never call this function after a big DB write that is still in a transaction.
2932  * This only makes sense after the possible lag inducing changes were committed.
2933  *
2934  * @param float|null $ifWritesSince Only wait if writes were done since this UNIX timestamp
2935  * @param string|bool $wiki Wiki identifier accepted by wfGetLB
2936  * @param string|bool $cluster Cluster name accepted by LBFactory. Default: false.
2937  * @param int|null $timeout Max wait time. Default: 1 day (cli), ~10 seconds (web)
2938  * @return bool Success (able to connect and no timeouts reached)
2939  * @deprecated since 1.27 Use LBFactory::waitForReplication
2940  */
2941 function wfWaitForSlaves(
2942         $ifWritesSince = null, $wiki = false, $cluster = false, $timeout = null
2943 ) {
2944         if ( $timeout === null ) {
2945                 $timeout = wfIsCLI() ? 60 : 10;
2946         }
2947
2948         if ( $cluster === '*' ) {
2949                 $cluster = false;
2950                 $wiki = false;
2951         } elseif ( $wiki === false ) {
2952                 $wiki = wfWikiID();
2953         }
2954
2955         try {
2956                 $lbFactory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
2957                 $lbFactory->waitForReplication( [
2958                         'wiki' => $wiki,
2959                         'cluster' => $cluster,
2960                         'timeout' => $timeout,
2961                         // B/C: first argument used to be "max seconds of lag"; ignore such values
2962                         'ifWritesSince' => ( $ifWritesSince > 1e9 ) ? $ifWritesSince : null
2963                 ] );
2964         } catch ( DBReplicationWaitError $e ) {
2965                 return false;
2966         }
2967
2968         return true;
2969 }
2970
2971 /**
2972  * Count down from $seconds to zero on the terminal, with a one-second pause
2973  * between showing each number. For use in command-line scripts.
2974  *
2975  * @deprecated since 1.31, use Maintenance::countDown()
2976  *
2977  * @codeCoverageIgnore
2978  * @param int $seconds
2979  */
2980 function wfCountDown( $seconds ) {
2981         wfDeprecated( __FUNCTION__, '1.31' );
2982         for ( $i = $seconds; $i >= 0; $i-- ) {
2983                 if ( $i != $seconds ) {
2984                         echo str_repeat( "\x08", strlen( $i + 1 ) );
2985                 }
2986                 echo $i;
2987                 flush();
2988                 if ( $i ) {
2989                         sleep( 1 );
2990                 }
2991         }
2992         echo "\n";
2993 }
2994
2995 /**
2996  * Replace all invalid characters with '-'.
2997  * Additional characters can be defined in $wgIllegalFileChars (see T22489).
2998  * By default, $wgIllegalFileChars includes ':', '/', '\'.
2999  *
3000  * @param string $name Filename to process
3001  * @return string
3002  */
3003 function wfStripIllegalFilenameChars( $name ) {
3004         global $wgIllegalFileChars;
3005         $illegalFileChars = $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '';
3006         $name = preg_replace(
3007                 "/[^" . Title::legalChars() . "]" . $illegalFileChars . "/",
3008                 '-',
3009                 $name
3010         );
3011         // $wgIllegalFileChars may not include '/' and '\', so we still need to do this
3012         $name = wfBaseName( $name );
3013         return $name;
3014 }
3015
3016 /**
3017  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit
3018  *
3019  * @return int Resulting value of the memory limit.
3020  */
3021 function wfMemoryLimit() {
3022         global $wgMemoryLimit;
3023         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3024         if ( $memlimit != -1 ) {
3025                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3026                 if ( $conflimit == -1 ) {
3027                         wfDebug( "Removing PHP's memory limit\n" );
3028                         Wikimedia\suppressWarnings();
3029                         ini_set( 'memory_limit', $conflimit );
3030                         Wikimedia\restoreWarnings();
3031                         return $conflimit;
3032                 } elseif ( $conflimit > $memlimit ) {
3033                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3034                         Wikimedia\suppressWarnings();
3035                         ini_set( 'memory_limit', $conflimit );
3036                         Wikimedia\restoreWarnings();
3037                         return $conflimit;
3038                 }
3039         }
3040         return $memlimit;
3041 }
3042
3043 /**
3044  * Set PHP's time limit to the larger of php.ini or $wgTransactionalTimeLimit
3045  *
3046  * @return int Prior time limit
3047  * @since 1.26
3048  */
3049 function wfTransactionalTimeLimit() {
3050         global $wgTransactionalTimeLimit;
3051
3052         $timeLimit = ini_get( 'max_execution_time' );
3053         // Note that CLI scripts use 0
3054         if ( $timeLimit > 0 && $wgTransactionalTimeLimit > $timeLimit ) {
3055                 set_time_limit( $wgTransactionalTimeLimit );
3056         }
3057
3058         ignore_user_abort( true ); // ignore client disconnects
3059
3060         return $timeLimit;
3061 }
3062
3063 /**
3064  * Converts shorthand byte notation to integer form
3065  *
3066  * @param string $string
3067  * @param int $default Returned if $string is empty
3068  * @return int
3069  */
3070 function wfShorthandToInteger( $string = '', $default = -1 ) {
3071         $string = trim( $string );
3072         if ( $string === '' ) {
3073                 return $default;
3074         }
3075         $last = $string[strlen( $string ) - 1];
3076         $val = intval( $string );
3077         switch ( $last ) {
3078                 case 'g':
3079                 case 'G':
3080                         $val *= 1024;
3081                         // break intentionally missing
3082                 case 'm':
3083                 case 'M':
3084                         $val *= 1024;
3085                         // break intentionally missing
3086                 case 'k':
3087                 case 'K':
3088                         $val *= 1024;
3089         }
3090
3091         return $val;
3092 }
3093
3094 /**
3095  * Get the normalised IETF language tag
3096  * See unit test for examples.
3097  * See mediawiki.language.bcp47 for the JavaScript implementation.
3098  *
3099  * @deprecated since 1.31, use LanguageCode::bcp47() directly.
3100  *
3101  * @param string $code The language code.
3102  * @return string The language code which complying with BCP 47 standards.
3103  */
3104 function wfBCP47( $code ) {
3105         wfDeprecated( __METHOD__, '1.31' );
3106         return LanguageCode::bcp47( $code );
3107 }
3108
3109 /**
3110  * Get a specific cache object.
3111  *
3112  * @deprecated since 1.32, use ObjectCache::getInstance() instead
3113  * @param int|string $cacheType A CACHE_* constants, or other key in $wgObjectCaches
3114  * @return BagOStuff
3115  */
3116 function wfGetCache( $cacheType ) {
3117         return ObjectCache::getInstance( $cacheType );
3118 }
3119
3120 /**
3121  * Get the main cache object
3122  *
3123  * @deprecated since 1.32, use ObjectCache::getLocalClusterInstance() instead
3124  * @return BagOStuff
3125  */
3126 function wfGetMainCache() {
3127         return ObjectCache::getLocalClusterInstance();
3128 }
3129
3130 /**
3131  * Get the cache object used by the message cache
3132  *
3133  * @return BagOStuff
3134  */
3135 function wfGetMessageCacheStorage() {
3136         global $wgMessageCacheType;
3137         return ObjectCache::getInstance( $wgMessageCacheType );
3138 }
3139
3140 /**
3141  * Call hook functions defined in $wgHooks
3142  *
3143  * @param string $event Event name
3144  * @param array $args Parameters passed to hook functions
3145  * @param string|null $deprecatedVersion Optionally mark hook as deprecated with version number
3146  *
3147  * @return bool True if no handler aborted the hook
3148  * @deprecated since 1.25 - use Hooks::run
3149  */
3150 function wfRunHooks( $event, array $args = [], $deprecatedVersion = null ) {
3151         wfDeprecated( __METHOD__, '1.25' );
3152         return Hooks::run( $event, $args, $deprecatedVersion );
3153 }
3154
3155 /**
3156  * Wrapper around php's unpack.
3157  *
3158  * @param string $format The format string (See php's docs)
3159  * @param string $data A binary string of binary data
3160  * @param int|bool $length The minimum length of $data or false. This is to
3161  *      prevent reading beyond the end of $data. false to disable the check.
3162  *
3163  * Also be careful when using this function to read unsigned 32 bit integer
3164  * because php might make it negative.
3165  *
3166  * @throws MWException If $data not long enough, or if unpack fails
3167  * @return array Associative array of the extracted data
3168  */
3169 function wfUnpack( $format, $data, $length = false ) {
3170         if ( $length !== false ) {
3171                 $realLen = strlen( $data );
3172                 if ( $realLen < $length ) {
3173                         throw new MWException( "Tried to use wfUnpack on a "
3174                                 . "string of length $realLen, but needed one "
3175                                 . "of at least length $length."
3176                         );
3177                 }
3178         }
3179
3180         Wikimedia\suppressWarnings();
3181         $result = unpack( $format, $data );
3182         Wikimedia\restoreWarnings();
3183
3184         if ( $result === false ) {
3185                 // If it cannot extract the packed data.
3186                 throw new MWException( "unpack could not unpack binary data" );
3187         }
3188         return $result;
3189 }
3190
3191 /**
3192  * Determine if an image exists on the 'bad image list'.
3193  *
3194  * The format of MediaWiki:Bad_image_list is as follows:
3195  *    * Only list items (lines starting with "*") are considered
3196  *    * The first link on a line must be a link to a bad image
3197  *    * Any subsequent links on the same line are considered to be exceptions,
3198  *      i.e. articles where the image may occur inline.
3199  *
3200  * @param string $name The image name to check
3201  * @param Title|bool $contextTitle The page on which the image occurs, if known
3202  * @param string|null $blacklist Wikitext of a file blacklist
3203  * @return bool
3204  */
3205 function wfIsBadImage( $name, $contextTitle = false, $blacklist = null ) {
3206         # Handle redirects; callers almost always hit wfFindFile() anyway,
3207         # so just use that method because it has a fast process cache.
3208         $file = wfFindFile( $name ); // get the final name
3209         $name = $file ? $file->getTitle()->getDBkey() : $name;
3210
3211         # Run the extension hook
3212         $bad = false;
3213         if ( !Hooks::run( 'BadImage', [ $name, &$bad ] ) ) {
3214                 return (bool)$bad;
3215         }
3216
3217         $cache = ObjectCache::getLocalServerInstance( 'hash' );
3218         $key = $cache->makeKey(
3219                 'bad-image-list', ( $blacklist === null ) ? 'default' : md5( $blacklist )
3220         );
3221         $badImages = $cache->get( $key );
3222
3223         if ( $badImages === false ) { // cache miss
3224                 if ( $blacklist === null ) {
3225                         $blacklist = wfMessage( 'bad_image_list' )->inContentLanguage()->plain(); // site list
3226                 }
3227                 # Build the list now
3228                 $badImages = [];
3229                 $lines = explode( "\n", $blacklist );
3230                 foreach ( $lines as $line ) {
3231                         # List items only
3232                         if ( substr( $line, 0, 1 ) !== '*' ) {
3233                                 continue;
3234                         }
3235
3236                         # Find all links
3237                         $m = [];
3238                         if ( !preg_match_all( '/\[\[:?(.*?)\]\]/', $line, $m ) ) {
3239                                 continue;
3240                         }
3241
3242                         $exceptions = [];
3243                         $imageDBkey = false;
3244                         foreach ( $m[1] as $i => $titleText ) {
3245                                 $title = Title::newFromText( $titleText );
3246                                 if ( !is_null( $title ) ) {
3247                                         if ( $i == 0 ) {
3248                                                 $imageDBkey = $title->getDBkey();
3249                                         } else {
3250                                                 $exceptions[$title->getPrefixedDBkey()] = true;
3251                                         }
3252                                 }
3253                         }
3254
3255                         if ( $imageDBkey !== false ) {
3256                                 $badImages[$imageDBkey] = $exceptions;
3257                         }
3258                 }
3259                 $cache->set( $key, $badImages, 60 );
3260         }
3261
3262         $contextKey = $contextTitle ? $contextTitle->getPrefixedDBkey() : false;
3263         $bad = isset( $badImages[$name] ) && !isset( $badImages[$name][$contextKey] );
3264
3265         return $bad;
3266 }
3267
3268 /**
3269  * Determine whether the client at a given source IP is likely to be able to
3270  * access the wiki via HTTPS.
3271  *
3272  * @param string $ip The IPv4/6 address in the normal human-readable form
3273  * @return bool
3274  */
3275 function wfCanIPUseHTTPS( $ip ) {
3276         $canDo = true;
3277         Hooks::run( 'CanIPUseHTTPS', [ $ip, &$canDo ] );
3278         return !!$canDo;
3279 }
3280
3281 /**
3282  * Determine input string is represents as infinity
3283  *
3284  * @param string $str The string to determine
3285  * @return bool
3286  * @since 1.25
3287  */
3288 function wfIsInfinity( $str ) {
3289         // These are hardcoded elsewhere in MediaWiki (e.g. mediawiki.special.block.js).
3290         $infinityValues = [ 'infinite', 'indefinite', 'infinity', 'never' ];
3291         return in_array( $str, $infinityValues );
3292 }
3293
3294 /**
3295  * Returns true if these thumbnail parameters match one that MediaWiki
3296  * requests from file description pages and/or parser output.
3297  *
3298  * $params is considered non-standard if they involve a non-standard
3299  * width or any non-default parameters aside from width and page number.
3300  * The number of possible files with standard parameters is far less than
3301  * that of all combinations; rate-limiting for them can thus be more generious.
3302  *
3303  * @param File $file
3304  * @param array $params
3305  * @return bool
3306  * @since 1.24 Moved from thumb.php to GlobalFunctions in 1.25
3307  */
3308 function wfThumbIsStandard( File $file, array $params ) {
3309         global $wgThumbLimits, $wgImageLimits, $wgResponsiveImages;
3310
3311         $multipliers = [ 1 ];
3312         if ( $wgResponsiveImages ) {
3313                 // These available sizes are hardcoded currently elsewhere in MediaWiki.
3314                 // @see Linker::processResponsiveImages
3315                 $multipliers[] = 1.5;
3316                 $multipliers[] = 2;
3317         }
3318
3319         $handler = $file->getHandler();
3320         if ( !$handler || !isset( $params['width'] ) ) {
3321                 return false;
3322         }
3323
3324         $basicParams = [];
3325         if ( isset( $params['page'] ) ) {
3326                 $basicParams['page'] = $params['page'];
3327         }
3328
3329         $thumbLimits = [];
3330         $imageLimits = [];
3331         // Expand limits to account for multipliers
3332         foreach ( $multipliers as $multiplier ) {
3333                 $thumbLimits = array_merge( $thumbLimits, array_map(
3334                         function ( $width ) use ( $multiplier ) {
3335                                 return round( $width * $multiplier );
3336                         }, $wgThumbLimits )
3337                 );
3338                 $imageLimits = array_merge( $imageLimits, array_map(
3339                         function ( $pair ) use ( $multiplier ) {
3340                                 return [
3341                                         round( $pair[0] * $multiplier ),
3342                                         round( $pair[1] * $multiplier ),
3343                                 ];
3344                         }, $wgImageLimits )
3345                 );
3346         }
3347
3348         // Check if the width matches one of $wgThumbLimits
3349         if ( in_array( $params['width'], $thumbLimits ) ) {
3350                 $normalParams = $basicParams + [ 'width' => $params['width'] ];
3351                 // Append any default values to the map (e.g. "lossy", "lossless", ...)
3352                 $handler->normaliseParams( $file, $normalParams );
3353         } else {
3354                 // If not, then check if the width matchs one of $wgImageLimits
3355                 $match = false;
3356                 foreach ( $imageLimits as $pair ) {
3357                         $normalParams = $basicParams + [ 'width' => $pair[0], 'height' => $pair[1] ];
3358                         // Decide whether the thumbnail should be scaled on width or height.
3359                         // Also append any default values to the map (e.g. "lossy", "lossless", ...)
3360                         $handler->normaliseParams( $file, $normalParams );
3361                         // Check if this standard thumbnail size maps to the given width
3362                         if ( $normalParams['width'] == $params['width'] ) {
3363                                 $match = true;
3364                                 break;
3365                         }
3366                 }
3367                 if ( !$match ) {
3368                         return false; // not standard for description pages
3369                 }
3370         }
3371
3372         // Check that the given values for non-page, non-width, params are just defaults
3373         foreach ( $params as $key => $value ) {
3374                 if ( !isset( $normalParams[$key] ) || $normalParams[$key] != $value ) {
3375                         return false;
3376                 }
3377         }
3378
3379         return true;
3380 }
3381
3382 /**
3383  * Merges two (possibly) 2 dimensional arrays into the target array ($baseArray).
3384  *
3385  * Values that exist in both values will be combined with += (all values of the array
3386  * of $newValues will be added to the values of the array of $baseArray, while values,
3387  * that exists in both, the value of $baseArray will be used).
3388  *
3389  * @param array $baseArray The array where you want to add the values of $newValues to
3390  * @param array $newValues An array with new values
3391  * @return array The combined array
3392  * @since 1.26
3393  */
3394 function wfArrayPlus2d( array $baseArray, array $newValues ) {
3395         // First merge items that are in both arrays
3396         foreach ( $baseArray as $name => &$groupVal ) {
3397                 if ( isset( $newValues[$name] ) ) {
3398                         $groupVal += $newValues[$name];
3399                 }
3400         }
3401         // Now add items that didn't exist yet
3402         $baseArray += $newValues;
3403
3404         return $baseArray;
3405 }
3406
3407 /**
3408  * Get system resource usage of current request context.
3409  * Invokes the getrusage(2) system call, requesting RUSAGE_SELF if on PHP5
3410  * or RUSAGE_THREAD if on HHVM. Returns false if getrusage is not available.
3411  *
3412  * @since 1.24
3413  * @return array|bool Resource usage data or false if no data available.
3414  */
3415 function wfGetRusage() {
3416         if ( !function_exists( 'getrusage' ) ) {
3417                 return false;
3418         } elseif ( defined( 'HHVM_VERSION' ) && PHP_OS === 'Linux' ) {
3419                 return getrusage( 2 /* RUSAGE_THREAD */ );
3420         } else {
3421                 return getrusage( 0 /* RUSAGE_SELF */ );
3422         }
3423 }