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\WrappedString;
  34
  35 /**
  36  * Load an extension
  37  *
  38  * This queues an extension to be loaded through
  39  * the ExtensionRegistry system.
  40  *
  41  * @param string $ext Name of the extension to load
  42  * @param string|null $path Absolute path of where to find the extension.json file
  43  * @since 1.25
  44  */
  45 function wfLoadExtension( $ext, $path = null ) {
  46         if ( !$path ) {
  47                 global $wgExtensionDirectory;
  48                 $path = "$wgExtensionDirectory/$ext/extension.json";
  49         }
  50         ExtensionRegistry::getInstance()->queue( $path );
  51 }
  52
  53 /**
  54  * Load multiple extensions at once
  55  *
  56  * Same as wfLoadExtension, but more efficient if you
  57  * are loading multiple extensions.
  58  *
  59  * If you want to specify custom paths, you should interact with
  60  * ExtensionRegistry directly.
  61  *
  62  * @see wfLoadExtension
  63  * @param string[] $exts Array of extension names to load
  64  * @since 1.25
  65  */
  66 function wfLoadExtensions( array $exts ) {
  67         global $wgExtensionDirectory;
  68         $registry = ExtensionRegistry::getInstance();
  69         foreach ( $exts as $ext ) {
  70                 $registry->queue( "$wgExtensionDirectory/$ext/extension.json" );
  71         }
  72 }
  73
  74 /**
  75  * Load a skin
  76  *
  77  * @see wfLoadExtension
  78  * @param string $skin Name of the extension to load
  79  * @param string|null $path Absolute path of where to find the skin.json file
  80  * @since 1.25
  81  */
  82 function wfLoadSkin( $skin, $path = null ) {
  83         if ( !$path ) {
  84                 global $wgStyleDirectory;
  85                 $path = "$wgStyleDirectory/$skin/skin.json";
  86         }
  87         ExtensionRegistry::getInstance()->queue( $path );
  88 }
  89
  90 /**
  91  * Load multiple skins at once
  92  *
  93  * @see wfLoadExtensions
  94  * @param string[] $skins Array of extension names to load
  95  * @since 1.25
  96  */
  97 function wfLoadSkins( array $skins ) {
  98         global $wgStyleDirectory;
  99         $registry = ExtensionRegistry::getInstance();
 100         foreach ( $skins as $skin ) {
 101                 $registry->queue( "$wgStyleDirectory/$skin/skin.json" );
 102         }
 103 }
 104
 105 /**
 106  * Like array_diff( $a, $b ) except that it works with two-dimensional arrays.
 107  * @param array $a
 108  * @param array $b
 109  * @return array
 110  */
 111 function wfArrayDiff2( $a, $b ) {
 112         return array_udiff( $a, $b, 'wfArrayDiff2_cmp' );
 113 }
 114
 115 /**
 116  * @param array|string $a
 117  * @param array|string $b
 118  * @return int
 119  */
 120 function wfArrayDiff2_cmp( $a, $b ) {
 121         if ( is_string( $a ) && is_string( $b ) ) {
 122                 return strcmp( $a, $b );
 123         } elseif ( count( $a ) !== count( $b ) ) {
 124                 return count( $a ) <=> count( $b );
 125         } else {
 126                 reset( $a );
 127                 reset( $b );
 128                 while ( key( $a ) !== null && key( $b ) !== null ) {
 129                         $valueA = current( $a );
 130                         $valueB = current( $b );
 131                         $cmp = strcmp( $valueA, $valueB );
 132                         if ( $cmp !== 0 ) {
 133                                 return $cmp;
 134                         }
 135                         next( $a );
 136                         next( $b );
 137                 }
 138                 return 0;
 139         }
 140 }
 141
 142 /**
 143  * @deprecated since 1.32, use array_filter() with ARRAY_FILTER_USE_BOTH directly
 144  *
 145  * @param array $arr
 146  * @param callable $callback Will be called with the array value and key (in that order) and
 147  *   should return a bool which will determine whether the array element is kept.
 148  * @return array
 149  */
 150 function wfArrayFilter( array $arr, callable $callback ) {
 151         return array_filter( $arr, $callback, ARRAY_FILTER_USE_BOTH );
 152 }
 153
 154 /**
 155  * @deprecated since 1.32, use array_filter() with ARRAY_FILTER_USE_KEY directly
 156  *
 157  * @param array $arr
 158  * @param callable $callback Will be called with the array key and should return a bool which
 159  *   will determine whether the array element is kept.
 160  * @return array
 161  */
 162 function wfArrayFilterByKey( array $arr, callable $callback ) {
 163         return array_filter( $arr, $callback, ARRAY_FILTER_USE_KEY );
 164 }
 165
 166 /**
 167  * Appends to second array if $value differs from that in $default
 168  *
 169  * @param string|int $key
 170  * @param mixed $value
 171  * @param mixed $default
 172  * @param array &$changed Array to alter
 173  * @throws MWException
 174  */
 175 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
 176         if ( is_null( $changed ) ) {
 177                 throw new MWException( 'GlobalFunctions::wfAppendToArrayIfNotDefault got null' );
 178         }
 179         if ( $default[$key] !== $value ) {
 180                 $changed[$key] = $value;
 181         }
 182 }
 183
 184 /**
 185  * Merge arrays in the style of getUserPermissionsErrors, with duplicate removal
 186  * e.g.
 187  *     wfMergeErrorArrays(
 188  *       [ [ 'x' ] ],
 189  *       [ [ 'x', '2' ] ],
 190  *       [ [ 'x' ] ],
 191  *       [ [ 'y' ] ]
 192  *     );
 193  * returns:
 194  *     [
 195  *       [ 'x', '2' ],
 196  *       [ 'x' ],
 197  *       [ 'y' ]
 198  *     ]
 199  *
 200  * @param array ...$args
 201  * @return array
 202  */
 203 function wfMergeErrorArrays( ...$args ) {
 204         $out = [];
 205         foreach ( $args as $errors ) {
 206                 foreach ( $errors as $params ) {
 207                         $originalParams = $params;
 208                         if ( $params[0] instanceof MessageSpecifier ) {
 209                                 $msg = $params[0];
 210                                 $params = array_merge( [ $msg->getKey() ], $msg->getParams() );
 211                         }
 212                         # @todo FIXME: Sometimes get nested arrays for $params,
 213                         # which leads to E_NOTICEs
 214                         $spec = implode( "\t", $params );
 215                         $out[$spec] = $originalParams;
 216                 }
 217         }
 218         return array_values( $out );
 219 }
 220
 221 /**
 222  * Insert array into another array after the specified *KEY*
 223  *
 224  * @param array $array The array.
 225  * @param array $insert The array to insert.
 226  * @param mixed $after The key to insert after
 227  * @return array
 228  */
 229 function wfArrayInsertAfter( array $array, array $insert, $after ) {
 230         // Find the offset of the element to insert after.
 231         $keys = array_keys( $array );
 232         $offsetByKey = array_flip( $keys );
 233
 234         $offset = $offsetByKey[$after];
 235
 236         // Insert at the specified offset
 237         $before = array_slice( $array, 0, $offset + 1, true );
 238         $after = array_slice( $array, $offset + 1, count( $array ) - $offset, true );
 239
 240         $output = $before + $insert + $after;
 241
 242         return $output;
 243 }
 244
 245 /**
 246  * Recursively converts the parameter (an object) to an array with the same data
 247  *
 248  * @param object|array $objOrArray
 249  * @param bool $recursive
 250  * @return array
 251  */
 252 function wfObjectToArray( $objOrArray, $recursive = true ) {
 253         $array = [];
 254         if ( is_object( $objOrArray ) ) {
 255                 $objOrArray = get_object_vars( $objOrArray );
 256         }
 257         foreach ( $objOrArray as $key => $value ) {
 258                 if ( $recursive && ( is_object( $value ) || is_array( $value ) ) ) {
 259                         $value = wfObjectToArray( $value );
 260                 }
 261
 262                 $array[$key] = $value;
 263         }
 264
 265         return $array;
 266 }
 267
 268 /**
 269  * Get a random decimal value in the domain of [0, 1), in a way
 270  * not likely to give duplicate values for any realistic
 271  * number of articles.
 272  *
 273  * @note This is designed for use in relation to Special:RandomPage
 274  *       and the page_random database field.
 275  *
 276  * @return string
 277  */
 278 function wfRandom() {
 279         // The maximum random value is "only" 2^31-1, so get two random
 280         // values to reduce the chance of dupes
 281         $max = mt_getrandmax() + 1;
 282         $rand = number_format( ( mt_rand() * $max + mt_rand() ) / $max / $max, 12, '.', '' );
 283         return $rand;
 284 }
 285
 286 /**
 287  * Get a random string containing a number of pseudo-random hex characters.
 288  *
 289  * @note This is not secure, if you are trying to generate some sort
 290  *       of token please use MWCryptRand instead.
 291  *
 292  * @param int $length The length of the string to generate
 293  * @return string
 294  * @since 1.20
 295  */
 296 function wfRandomString( $length = 32 ) {
 297         $str = '';
 298         for ( $n = 0; $n < $length; $n += 7 ) {
 299                 $str .= sprintf( '%07x', mt_rand() & 0xfffffff );
 300         }
 301         return substr( $str, 0, $length );
 302 }
 303
 304 /**
 305  * We want some things to be included as literal characters in our title URLs
 306  * for prettiness, which urlencode encodes by default.  According to RFC 1738,
 307  * all of the following should be safe:
 308  *
 309  * ;:@&=$-_.+!*'(),
 310  *
 311  * RFC 1738 says ~ is unsafe, however RFC 3986 considers it an unreserved
 312  * character which should not be encoded. More importantly, google chrome
 313  * always converts %7E back to ~, and converting it in this function can
 314  * cause a redirect loop (T105265).
 315  *
 316  * But + is not safe because it's used to indicate a space; &= are only safe in
 317  * paths and not in queries (and we don't distinguish here); ' seems kind of
 318  * scary; and urlencode() doesn't touch -_. to begin with.  Plus, although /
 319  * is reserved, we don't care.  So the list we unescape is:
 320  *
 321  * ;:@$!*(),/~
 322  *
 323  * However, IIS7 redirects fail when the url contains a colon (see T24709),
 324  * so no fancy : for IIS7.
 325  *
 326  * %2F in the page titles seems to fatally break for some reason.
 327  *
 328  * @param string $s
 329  * @return string
 330  */
 331 function wfUrlencode( $s ) {
 332         static $needle;
 333
 334         if ( is_null( $s ) ) {
 335                 $needle = null;
 336                 return '';
 337         }
 338
 339         if ( is_null( $needle ) ) {
 340                 $needle = [ '%3B', '%40', '%24', '%21', '%2A', '%28', '%29', '%2C', '%2F', '%7E' ];
 341                 if ( !isset( $_SERVER['SERVER_SOFTWARE'] ) ||
 342                         ( strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/7' ) === false )
 343                 ) {
 344                         $needle[] = '%3A';
 345                 }
 346         }
 347
 348         $s = urlencode( $s );
 349         $s = str_ireplace(
 350                 $needle,
 351                 [ ';', '@', '$', '!', '*', '(', ')', ',', '/', '~', ':' ],
 352                 $s
 353         );
 354
 355         return $s;
 356 }
 357
 358 /**
 359  * This function takes one or two arrays as input, and returns a CGI-style string, e.g.
 360  * "days=7&limit=100". Options in the first array override options in the second.
 361  * Options set to null or false will not be output.
 362  *
 363  * @param array $array1 ( String|Array )
 364  * @param array|null $array2 ( String|Array )
 365  * @param string $prefix
 366  * @return string
 367  */
 368 function wfArrayToCgi( $array1, $array2 = null, $prefix = '' ) {
 369         if ( !is_null( $array2 ) ) {
 370                 $array1 = $array1 + $array2;
 371         }
 372
 373         $cgi = '';
 374         foreach ( $array1 as $key => $value ) {
 375                 if ( !is_null( $value ) && $value !== false ) {
 376                         if ( $cgi != '' ) {
 377                                 $cgi .= '&';
 378                         }
 379                         if ( $prefix !== '' ) {
 380                                 $key = $prefix . "[$key]";
 381                         }
 382                         if ( is_array( $value ) ) {
 383                                 $firstTime = true;
 384                                 foreach ( $value as $k => $v ) {
 385                                         $cgi .= $firstTime ? '' : '&';
 386                                         if ( is_array( $v ) ) {
 387                                                 $cgi .= wfArrayToCgi( $v, null, $key . "[$k]" );
 388                                         } else {
 389                                                 $cgi .= urlencode( $key . "[$k]" ) . '=' . urlencode( $v );
 390                                         }
 391                                         $firstTime = false;
 392                                 }
 393                         } else {
 394                                 if ( is_object( $value ) ) {
 395                                         $value = $value->__toString();
 396                                 }
 397                                 $cgi .= urlencode( $key ) . '=' . urlencode( $value );
 398                         }
 399                 }
 400         }
 401         return $cgi;
 402 }
 403
 404 /**
 405  * This is the logical opposite of wfArrayToCgi(): it accepts a query string as
 406  * its argument and returns the same string in array form.  This allows compatibility
 407  * with legacy functions that accept raw query strings instead of nice
 408  * arrays.  Of course, keys and values are urldecode()d.
 409  *
 410  * @param string $query Query string
 411  * @return string[] Array version of input
 412  */
 413 function wfCgiToArray( $query ) {
 414         if ( isset( $query[0] ) && $query[0] == '?' ) {
 415                 $query = substr( $query, 1 );
 416         }
 417         $bits = explode( '&', $query );
 418         $ret = [];
 419         foreach ( $bits as $bit ) {
 420                 if ( $bit === '' ) {
 421                         continue;
 422                 }
 423                 if ( strpos( $bit, '=' ) === false ) {
 424                         // Pieces like &qwerty become 'qwerty' => '' (at least this is what php does)
 425                         $key = $bit;
 426                         $value = '';
 427                 } else {
 428                         list( $key, $value ) = explode( '=', $bit );
 429                 }
 430                 $key = urldecode( $key );
 431                 $value = urldecode( $value );
 432                 if ( strpos( $key, '[' ) !== false ) {
 433                         $keys = array_reverse( explode( '[', $key ) );
 434                         $key = array_pop( $keys );
 435                         $temp = $value;
 436                         foreach ( $keys as $k ) {
 437                                 $k = substr( $k, 0, -1 );
 438                                 $temp = [ $k => $temp ];
 439                         }
 440                         if ( isset( $ret[$key] ) ) {
 441                                 $ret[$key] = array_merge( $ret[$key], $temp );
 442                         } else {
 443                                 $ret[$key] = $temp;
 444                         }
 445                 } else {
 446                         $ret[$key] = $value;
 447                 }
 448         }
 449         return $ret;
 450 }
 451
 452 /**
 453  * Append a query string to an existing URL, which may or may not already
 454  * have query string parameters already. If so, they will be combined.
 455  *
 456  * @param string $url
 457  * @param string|string[] $query String or associative array
 458  * @return string
 459  */
 460 function wfAppendQuery( $url, $query ) {
 461         if ( is_array( $query ) ) {
 462                 $query = wfArrayToCgi( $query );
 463         }
 464         if ( $query != '' ) {
 465                 // Remove the fragment, if there is one
 466                 $fragment = false;
 467                 $hashPos = strpos( $url, '#' );
 468                 if ( $hashPos !== false ) {
 469                         $fragment = substr( $url, $hashPos );
 470                         $url = substr( $url, 0, $hashPos );
 471                 }
 472
 473                 // Add parameter
 474                 if ( strpos( $url, '?' ) === false ) {
 475                         $url .= '?';
 476                 } else {
 477                         $url .= '&';
 478                 }
 479                 $url .= $query;
 480
 481                 // Put the fragment back
 482                 if ( $fragment !== false ) {
 483                         $url .= $fragment;
 484                 }
 485         }
 486         return $url;
 487 }
 488
 489 /**
 490  * Expand a potentially local URL to a fully-qualified URL. Assumes $wgServer
 491  * is correct.
 492  *
 493  * The meaning of the PROTO_* constants is as follows:
 494  * PROTO_HTTP: Output a URL starting with http://
 495  * PROTO_HTTPS: Output a URL starting with https://
 496  * PROTO_RELATIVE: Output a URL starting with // (protocol-relative URL)
 497  * PROTO_CURRENT: Output a URL starting with either http:// or https:// , depending
 498  *    on which protocol was used for the current incoming request
 499  * PROTO_CANONICAL: For URLs without a domain, like /w/index.php , use $wgCanonicalServer.
 500  *    For protocol-relative URLs, use the protocol of $wgCanonicalServer
 501  * PROTO_INTERNAL: Like PROTO_CANONICAL, but uses $wgInternalServer instead of $wgCanonicalServer
 502  *
 503  * @todo this won't work with current-path-relative URLs
 504  * like "subdir/foo.html", etc.
 505  *
 506  * @param string $url Either fully-qualified or a local path + query
 507  * @param string|int|null $defaultProto One of the PROTO_* constants. Determines the
 508  *    protocol to use if $url or $wgServer is protocol-relative
 509  * @return string|false Fully-qualified URL, current-path-relative URL or false if
 510  *    no valid URL can be constructed
 511  */
 512 function wfExpandUrl( $url, $defaultProto = PROTO_CURRENT ) {
 513         global $wgServer, $wgCanonicalServer, $wgInternalServer, $wgRequest,
 514                 $wgHttpsPort;
 515         if ( $defaultProto === PROTO_CANONICAL ) {
 516                 $serverUrl = $wgCanonicalServer;
 517         } elseif ( $defaultProto === PROTO_INTERNAL && $wgInternalServer !== false ) {
 518                 // Make $wgInternalServer fall back to $wgServer if not set
 519                 $serverUrl = $wgInternalServer;
 520         } else {
 521                 $serverUrl = $wgServer;
 522                 if ( $defaultProto === PROTO_CURRENT ) {
 523                         $defaultProto = $wgRequest->getProtocol() . '://';
 524                 }
 525         }
 526
 527         // Analyze $serverUrl to obtain its protocol
 528         $bits = wfParseUrl( $serverUrl );
 529         $serverHasProto = $bits && $bits['scheme'] != '';
 530
 531         if ( $defaultProto === PROTO_CANONICAL || $defaultProto === PROTO_INTERNAL ) {
 532                 if ( $serverHasProto ) {
 533                         $defaultProto = $bits['scheme'] . '://';
 534                 } else {
 535                         // $wgCanonicalServer or $wgInternalServer doesn't have a protocol.
 536                         // This really isn't supposed to happen. Fall back to HTTP in this
 537                         // ridiculous case.
 538                         $defaultProto = PROTO_HTTP;
 539                 }
 540         }
 541
 542         $defaultProtoWithoutSlashes = substr( $defaultProto, 0, -2 );
 543
 544         if ( substr( $url, 0, 2 ) == '//' ) {
 545                 $url = $defaultProtoWithoutSlashes . $url;
 546         } elseif ( substr( $url, 0, 1 ) == '/' ) {
 547                 // If $serverUrl is protocol-relative, prepend $defaultProtoWithoutSlashes,
 548                 // otherwise leave it alone.
 549                 if ( $serverHasProto ) {
 550                         $url = $serverUrl . $url;
 551                 } else {
 552                         // If an HTTPS URL is synthesized from a protocol-relative $wgServer, allow the
 553                         // user to override the port number (T67184)
 554                         if ( $defaultProto === PROTO_HTTPS && $wgHttpsPort != 443 ) {
 555                                 if ( isset( $bits['port'] ) ) {
 556                                         throw new Exception( 'A protocol-relative $wgServer may not contain a port number' );
 557                                 }
 558                                 $url = $defaultProtoWithoutSlashes . $serverUrl . ':' . $wgHttpsPort . $url;
 559                         } else {
 560                                 $url = $defaultProtoWithoutSlashes . $serverUrl . $url;
 561                         }
 562                 }
 563         }
 564
 565         $bits = wfParseUrl( $url );
 566
 567         if ( $bits && isset( $bits['path'] ) ) {
 568                 $bits['path'] = wfRemoveDotSegments( $bits['path'] );
 569                 return wfAssembleUrl( $bits );
 570         } elseif ( $bits ) {
 571                 # No path to expand
 572                 return $url;
 573         } elseif ( substr( $url, 0, 1 ) != '/' ) {
 574                 # URL is a relative path
 575                 return wfRemoveDotSegments( $url );
 576         }
 577
 578         # Expanded URL is not valid.
 579         return false;
 580 }
 581
 582 /**
 583  * Get the wiki's "server", i.e. the protocol and host part of the URL, with a
 584  * protocol specified using a PROTO_* constant as in wfExpandUrl()
 585  *
 586  * @since 1.32
 587  * @param string|int|null $proto One of the PROTO_* constants.
 588  * @return string The URL
 589  */
 590 function wfGetServerUrl( $proto ) {
 591         $url = wfExpandUrl( '/', $proto );
 592         return substr( $url, 0, -1 );
 593 }
 594
 595 /**
 596  * This function will reassemble a URL parsed with wfParseURL.  This is useful
 597  * if you need to edit part of a URL and put it back together.
 598  *
 599  * This is the basic structure used (brackets contain keys for $urlParts):
 600  * [scheme][delimiter][user]:[pass]@[host]:[port][path]?[query]#[fragment]
 601  *
 602  * @todo Need to integrate this into wfExpandUrl (see T34168)
 603  *
 604  * @since 1.19
 605  * @param array $urlParts URL parts, as output from wfParseUrl
 606  * @return string URL assembled from its component parts
 607  */
 608 function wfAssembleUrl( $urlParts ) {
 609         $result = '';
 610
 611         if ( isset( $urlParts['delimiter'] ) ) {
 612                 if ( isset( $urlParts['scheme'] ) ) {
 613                         $result .= $urlParts['scheme'];
 614                 }
 615
 616                 $result .= $urlParts['delimiter'];
 617         }
 618
 619         if ( isset( $urlParts['host'] ) ) {
 620                 if ( isset( $urlParts['user'] ) ) {
 621                         $result .= $urlParts['user'];
 622                         if ( isset( $urlParts['pass'] ) ) {
 623                                 $result .= ':' . $urlParts['pass'];
 624                         }
 625                         $result .= '@';
 626                 }
 627
 628                 $result .= $urlParts['host'];
 629
 630                 if ( isset( $urlParts['port'] ) ) {
 631                         $result .= ':' . $urlParts['port'];
 632                 }
 633         }
 634
 635         if ( isset( $urlParts['path'] ) ) {
 636                 $result .= $urlParts['path'];
 637         }
 638
 639         if ( isset( $urlParts['query'] ) ) {
 640                 $result .= '?' . $urlParts['query'];
 641         }
 642
 643         if ( isset( $urlParts['fragment'] ) ) {
 644                 $result .= '#' . $urlParts['fragment'];
 645         }
 646
 647         return $result;
 648 }
 649
 650 /**
 651  * Remove all dot-segments in the provided URL path.  For example,
 652  * '/a/./b/../c/' becomes '/a/c/'.  For details on the algorithm, please see
 653  * RFC3986 section 5.2.4.
 654  *
 655  * @todo Need to integrate this into wfExpandUrl (see T34168)
 656  *
 657  * @since 1.19
 658  *
 659  * @param string $urlPath URL path, potentially containing dot-segments
 660  * @return string URL path with all dot-segments removed
 661  */
 662 function wfRemoveDotSegments( $urlPath ) {
 663         $output = '';
 664         $inputOffset = 0;
 665         $inputLength = strlen( $urlPath );
 666
 667         while ( $inputOffset < $inputLength ) {
 668                 $prefixLengthOne = substr( $urlPath, $inputOffset, 1 );
 669                 $prefixLengthTwo = substr( $urlPath, $inputOffset, 2 );
 670                 $prefixLengthThree = substr( $urlPath, $inputOffset, 3 );
 671                 $prefixLengthFour = substr( $urlPath, $inputOffset, 4 );
 672                 $trimOutput = false;
 673
 674                 if ( $prefixLengthTwo == './' ) {
 675                         # Step A, remove leading "./"
 676                         $inputOffset += 2;
 677                 } elseif ( $prefixLengthThree == '../' ) {
 678                         # Step A, remove leading "../"
 679                         $inputOffset += 3;
 680                 } elseif ( ( $prefixLengthTwo == '/.' ) && ( $inputOffset + 2 == $inputLength ) ) {
 681                         # Step B, replace leading "/.$" with "/"
 682                         $inputOffset += 1;
 683                         $urlPath[$inputOffset] = '/';
 684                 } elseif ( $prefixLengthThree == '/./' ) {
 685                         # Step B, replace leading "/./" with "/"
 686                         $inputOffset += 2;
 687                 } elseif ( $prefixLengthThree == '/..' && ( $inputOffset + 3 == $inputLength ) ) {
 688                         # Step C, replace leading "/..$" with "/" and
 689                         # remove last path component in output
 690                         $inputOffset += 2;
 691                         $urlPath[$inputOffset] = '/';
 692                         $trimOutput = true;
 693                 } elseif ( $prefixLengthFour == '/../' ) {
 694                         # Step C, replace leading "/../" with "/" and
 695                         # remove last path component in output
 696                         $inputOffset += 3;
 697                         $trimOutput = true;
 698                 } elseif ( ( $prefixLengthOne == '.' ) && ( $inputOffset + 1 == $inputLength ) ) {
 699                         # Step D, remove "^.$"
 700                         $inputOffset += 1;
 701                 } elseif ( ( $prefixLengthTwo == '..' ) && ( $inputOffset + 2 == $inputLength ) ) {
 702                         # Step D, remove "^..$"
 703                         $inputOffset += 2;
 704                 } else {
 705                         # Step E, move leading path segment to output
 706                         if ( $prefixLengthOne == '/' ) {
 707                                 $slashPos = strpos( $urlPath, '/', $inputOffset + 1 );
 708                         } else {
 709                                 $slashPos = strpos( $urlPath, '/', $inputOffset );
 710                         }
 711                         if ( $slashPos === false ) {
 712                                 $output .= substr( $urlPath, $inputOffset );
 713                                 $inputOffset = $inputLength;
 714                         } else {
 715                                 $output .= substr( $urlPath, $inputOffset, $slashPos - $inputOffset );
 716                                 $inputOffset += $slashPos - $inputOffset;
 717                         }
 718                 }
 719
 720                 if ( $trimOutput ) {
 721                         $slashPos = strrpos( $output, '/' );
 722                         if ( $slashPos === false ) {
 723                                 $output = '';
 724                         } else {
 725                                 $output = substr( $output, 0, $slashPos );
 726                         }
 727                 }
 728         }
 729
 730         return $output;
 731 }
 732
 733 /**
 734  * Returns a regular expression of url protocols
 735  *
 736  * @param bool $includeProtocolRelative If false, remove '//' from the returned protocol list.
 737  *        DO NOT USE this directly, use wfUrlProtocolsWithoutProtRel() instead
 738  * @return string
 739  */
 740 function wfUrlProtocols( $includeProtocolRelative = true ) {
 741         global $wgUrlProtocols;
 742
 743         // Cache return values separately based on $includeProtocolRelative
 744         static $withProtRel = null, $withoutProtRel = null;
 745         $cachedValue = $includeProtocolRelative ? $withProtRel : $withoutProtRel;
 746         if ( !is_null( $cachedValue ) ) {
 747                 return $cachedValue;
 748         }
 749
 750         // Support old-style $wgUrlProtocols strings, for backwards compatibility
 751         // with LocalSettings files from 1.5
 752         if ( is_array( $wgUrlProtocols ) ) {
 753                 $protocols = [];
 754                 foreach ( $wgUrlProtocols as $protocol ) {
 755                         // Filter out '//' if !$includeProtocolRelative
 756                         if ( $includeProtocolRelative || $protocol !== '//' ) {
 757                                 $protocols[] = preg_quote( $protocol, '/' );
 758                         }
 759                 }
 760
 761                 $retval = implode( '|', $protocols );
 762         } else {
 763                 // Ignore $includeProtocolRelative in this case
 764                 // This case exists for pre-1.6 compatibility, and we can safely assume
 765                 // that '//' won't appear in a pre-1.6 config because protocol-relative
 766                 // URLs weren't supported until 1.18
 767                 $retval = $wgUrlProtocols;
 768         }
 769
 770         // Cache return value
 771         if ( $includeProtocolRelative ) {
 772                 $withProtRel = $retval;
 773         } else {
 774                 $withoutProtRel = $retval;
 775         }
 776         return $retval;
 777 }
 778
 779 /**
 780  * Like wfUrlProtocols(), but excludes '//' from the protocol list. Use this if
 781  * you need a regex that matches all URL protocols but does not match protocol-
 782  * relative URLs
 783  * @return string
 784  */
 785 function wfUrlProtocolsWithoutProtRel() {
 786         return wfUrlProtocols( false );
 787 }
 788
 789 /**
 790  * parse_url() work-alike, but non-broken.  Differences:
 791  *
 792  * 1) Does not raise warnings on bad URLs (just returns false).
 793  * 2) Handles protocols that don't use :// (e.g., mailto: and news:, as well as
 794  *    protocol-relative URLs) correctly.
 795  * 3) Adds a "delimiter" element to the array (see (2)).
 796  * 4) Verifies that the protocol is on the $wgUrlProtocols whitelist.
 797  * 5) Rejects some invalid URLs that parse_url doesn't, e.g. the empty string or URLs starting with
 798  *    a line feed character.
 799  *
 800  * @param string $url A URL to parse
 801  * @return string[]|bool Bits of the URL in an associative array, or false on failure.
 802  *   Possible fields:
 803  *   - scheme: URI scheme (protocol), e.g. 'http', 'mailto'. Lowercase, always present, but can
 804  *       be an empty string for protocol-relative URLs.
 805  *   - delimiter: either '://', ':' or '//'. Always present.
 806  *   - host: domain name / IP. Always present, but could be an empty string, e.g. for file: URLs.
 807  *   - user: user name, e.g. for HTTP Basic auth URLs such as http://user:pass@example.com/
 808  *       Missing when there is no username.
 809  *   - pass: password, same as above.
 810  *   - path: path including the leading /. Will be missing when empty (e.g. 'http://example.com')
 811  *   - query: query string (as a string; see wfCgiToArray() for parsing it), can be missing.
 812  *   - fragment: the part after #, can be missing.
 813  */
 814 function wfParseUrl( $url ) {
 815         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
 816
 817         // Protocol-relative URLs are handled really badly by parse_url(). It's so
 818         // bad that the easiest way to handle them is to just prepend 'http:' and
 819         // strip the protocol out later.
 820         $wasRelative = substr( $url, 0, 2 ) == '//';
 821         if ( $wasRelative ) {
 822                 $url = "http:$url";
 823         }
 824         Wikimedia\suppressWarnings();
 825         $bits = parse_url( $url );
 826         Wikimedia\restoreWarnings();
 827         // parse_url() returns an array without scheme for some invalid URLs, e.g.
 828         // parse_url("%0Ahttp://example.com") == [ 'host' => '%0Ahttp', 'path' => 'example.com' ]
 829         if ( !$bits || !isset( $bits['scheme'] ) ) {
 830                 return false;
 831         }
 832
 833         // parse_url() incorrectly handles schemes case-sensitively. Convert it to lowercase.
 834         $bits['scheme'] = strtolower( $bits['scheme'] );
 835
 836         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
 837         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
 838                 $bits['delimiter'] = '://';
 839         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
 840                 $bits['delimiter'] = ':';
 841                 // parse_url detects for news: and mailto: the host part of an url as path
 842                 // We have to correct this wrong detection
 843                 if ( isset( $bits['path'] ) ) {
 844                         $bits['host'] = $bits['path'];
 845                         $bits['path'] = '';
 846                 }
 847         } else {
 848                 return false;
 849         }
 850
 851         /* Provide an empty host for eg. file:/// urls (see T30627) */
 852         if ( !isset( $bits['host'] ) ) {
 853                 $bits['host'] = '';
 854
 855                 // See T47069
 856                 if ( isset( $bits['path'] ) ) {
 857                         /* parse_url loses the third / for file:///c:/ urls (but not on variants) */
 858                         if ( substr( $bits['path'], 0, 1 ) !== '/' ) {
 859                                 $bits['path'] = '/' . $bits['path'];
 860                         }
 861                 } else {
 862                         $bits['path'] = '';
 863                 }
 864         }
 865
 866         // If the URL was protocol-relative, fix scheme and delimiter
 867         if ( $wasRelative ) {
 868                 $bits['scheme'] = '';
 869                 $bits['delimiter'] = '//';
 870         }
 871         return $bits;
 872 }
 873
 874 /**
 875  * Take a URL, make sure it's expanded to fully qualified, and replace any
 876  * encoded non-ASCII Unicode characters with their UTF-8 original forms
 877  * for more compact display and legibility for local audiences.
 878  *
 879  * @todo handle punycode domains too
 880  *
 881  * @param string $url
 882  * @return string
 883  */
 884 function wfExpandIRI( $url ) {
 885         return preg_replace_callback(
 886                 '/((?:%[89A-F][0-9A-F])+)/i',
 887                 function ( array $matches ) {
 888                         return urldecode( $matches[1] );
 889                 },
 890                 wfExpandUrl( $url )
 891         );
 892 }
 893
 894 /**
 895  * Make URL indexes, appropriate for the el_index field of externallinks.
 896  *
 897  * @deprecated since 1.33, use LinkFilter::makeIndexes() instead
 898  * @param string $url
 899  * @return array
 900  */
 901 function wfMakeUrlIndexes( $url ) {
 902         wfDeprecated( __FUNCTION__, '1.33' );
 903         return LinkFilter::makeIndexes( $url );
 904 }
 905
 906 /**
 907  * Check whether a given URL has a domain that occurs in a given set of domains
 908  * @param string $url
 909  * @param array $domains Array of domains (strings)
 910  * @return bool True if the host part of $url ends in one of the strings in $domains
 911  */
 912 function wfMatchesDomainList( $url, $domains ) {
 913         $bits = wfParseUrl( $url );
 914         if ( is_array( $bits ) && isset( $bits['host'] ) ) {
 915                 $host = '.' . $bits['host'];
 916                 foreach ( (array)$domains as $domain ) {
 917                         $domain = '.' . $domain;
 918                         if ( substr( $host, -strlen( $domain ) ) === $domain ) {
 919                                 return true;
 920                         }
 921                 }
 922         }
 923         return false;
 924 }
 925
 926 /**
 927  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
 928  * In normal operation this is a NOP.
 929  *
 930  * Controlling globals:
 931  * $wgDebugLogFile - points to the log file
 932  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
 933  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
 934  *
 935  * @since 1.25 support for additional context data
 936  *
 937  * @param string $text
 938  * @param string|bool $dest Destination of the message:
 939  *     - 'all': both to the log and HTML (debug toolbar or HTML comments)
 940  *     - 'private': excluded from HTML output
 941  *   For backward compatibility, it can also take a boolean:
 942  *     - true: same as 'all'
 943  *     - false: same as 'private'
 944  * @param array $context Additional logging context data
 945  */
 946 function wfDebug( $text, $dest = 'all', array $context = [] ) {
 947         global $wgDebugRawPage, $wgDebugLogPrefix;
 948         global $wgDebugTimestamps;
 949
 950         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
 951                 return;
 952         }
 953
 954         $text = trim( $text );
 955
 956         if ( $wgDebugTimestamps ) {
 957                 $context['seconds_elapsed'] = sprintf(
 958                         '%6.4f',
 959                         microtime( true ) - $_SERVER['REQUEST_TIME_FLOAT']
 960                 );
 961                 $context['memory_used'] = sprintf(
 962                         '%5.1fM',
 963                         ( memory_get_usage( true ) / ( 1024 * 1024 ) )
 964                 );
 965         }
 966
 967         if ( $wgDebugLogPrefix !== '' ) {
 968                 $context['prefix'] = $wgDebugLogPrefix;
 969         }
 970         $context['private'] = ( $dest === false || $dest === 'private' );
 971
 972         $logger = LoggerFactory::getInstance( 'wfDebug' );
 973         $logger->debug( $text, $context );
 974 }
 975
 976 /**
 977  * Returns true if debug logging should be suppressed if $wgDebugRawPage = false
 978  * @return bool
 979  */
 980 function wfIsDebugRawPage() {
 981         static $cache;
 982         if ( $cache !== null ) {
 983                 return $cache;
 984         }
 985         // Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
 986         // phpcs:ignore MediaWiki.Usage.SuperGlobalsUsage.SuperGlobals
 987         if ( ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' )
 988                 || (
 989                         isset( $_SERVER['SCRIPT_NAME'] )
 990                         && substr( $_SERVER['SCRIPT_NAME'], -8 ) == 'load.php'
 991                 )
 992         ) {
 993                 $cache = true;
 994         } else {
 995                 $cache = false;
 996         }
 997         return $cache;
 998 }
 999
1000 /**
1001  * Send a line giving PHP memory usage.
1002  *
1003  * @param bool $exact Print exact byte values instead of kibibytes (default: false)
1004  */
1005 function wfDebugMem( $exact = false ) {
1006         $mem = memory_get_usage();
1007         if ( !$exact ) {
1008                 $mem = floor( $mem / 1024 ) . ' KiB';
1009         } else {
1010                 $mem .= ' B';
1011         }
1012         wfDebug( "Memory usage: $mem\n" );
1013 }
1014
1015 /**
1016  * Send a line to a supplementary debug log file, if configured, or main debug
1017  * log if not.
1018  *
1019  * To configure a supplementary log file, set $wgDebugLogGroups[$logGroup] to
1020  * a string filename or an associative array mapping 'destination' to the
1021  * desired filename. The associative array may also contain a 'sample' key
1022  * with an integer value, specifying a sampling factor. Sampled log events
1023  * will be emitted with a 1 in N random chance.
1024  *
1025  * @since 1.23 support for sampling log messages via $wgDebugLogGroups.
1026  * @since 1.25 support for additional context data
1027  * @since 1.25 sample behavior dependent on configured $wgMWLoggerDefaultSpi
1028  *
1029  * @param string $logGroup
1030  * @param string $text
1031  * @param string|bool $dest Destination of the message:
1032  *     - 'all': both to the log and HTML (debug toolbar or HTML comments)
1033  *     - 'private': only to the specific log if set in $wgDebugLogGroups and
1034  *       discarded otherwise
1035  *   For backward compatibility, it can also take a boolean:
1036  *     - true: same as 'all'
1037  *     - false: same as 'private'
1038  * @param array $context Additional logging context data
1039  */
1040 function wfDebugLog(
1041         $logGroup, $text, $dest = 'all', array $context = []
1042 ) {
1043         $text = trim( $text );
1044
1045         $logger = LoggerFactory::getInstance( $logGroup );
1046         $context['private'] = ( $dest === false || $dest === 'private' );
1047         $logger->info( $text, $context );
1048 }
1049
1050 /**
1051  * Log for database errors
1052  *
1053  * @since 1.25 support for additional context data
1054  *
1055  * @param string $text Database error message.
1056  * @param array $context Additional logging context data
1057  */
1058 function wfLogDBError( $text, array $context = [] ) {
1059         $logger = LoggerFactory::getInstance( 'wfLogDBError' );
1060         $logger->error( trim( $text ), $context );
1061 }
1062
1063 /**
1064  * Throws a warning that $function is deprecated
1065  *
1066  * @param string $function
1067  * @param string|bool $version Version of MediaWiki that the function
1068  *    was deprecated in (Added in 1.19).
1069  * @param string|bool $component Added in 1.19.
1070  * @param int $callerOffset How far up the call stack is the original
1071  *    caller. 2 = function that called the function that called
1072  *    wfDeprecated (Added in 1.20)
1073  *
1074  * @return null
1075  */
1076 function wfDeprecated( $function, $version = false, $component = false, $callerOffset = 2 ) {
1077         MWDebug::deprecated( $function, $version, $component, $callerOffset + 1 );
1078 }
1079
1080 /**
1081  * Send a warning either to the debug log or in a PHP error depending on
1082  * $wgDevelopmentWarnings. To log warnings in production, use wfLogWarning() instead.
1083  *
1084  * @param string $msg Message to send
1085  * @param int $callerOffset Number of items to go back in the backtrace to
1086  *        find the correct caller (1 = function calling wfWarn, ...)
1087  * @param int $level PHP error level; defaults to E_USER_NOTICE;
1088  *        only used when $wgDevelopmentWarnings is true
1089  */
1090 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
1091         MWDebug::warning( $msg, $callerOffset + 1, $level, 'auto' );
1092 }
1093
1094 /**
1095  * Send a warning as a PHP error and the debug log. This is intended for logging
1096  * warnings in production. For logging development warnings, use WfWarn instead.
1097  *
1098  * @param string $msg Message to send
1099  * @param int $callerOffset Number of items to go back in the backtrace to
1100  *        find the correct caller (1 = function calling wfLogWarning, ...)
1101  * @param int $level PHP error level; defaults to E_USER_WARNING
1102  */
1103 function wfLogWarning( $msg, $callerOffset = 1, $level = E_USER_WARNING ) {
1104         MWDebug::warning( $msg, $callerOffset + 1, $level, 'production' );
1105 }
1106
1107 /**
1108  * @todo document
1109  * @todo Move logic to MediaWiki.php
1110  */
1111 function wfLogProfilingData() {
1112         global $wgDebugLogGroups, $wgDebugRawPage;
1113
1114         $context = RequestContext::getMain();
1115         $request = $context->getRequest();
1116
1117         $profiler = Profiler::instance();
1118         $profiler->setContext( $context );
1119         $profiler->logData();
1120
1121         // Send out any buffered statsd metrics as needed
1122         MediaWiki::emitBufferedStatsdData(
1123                 MediaWikiServices::getInstance()->getStatsdDataFactory(),
1124                 $context->getConfig()
1125         );
1126
1127         // Profiling must actually be enabled...
1128         if ( $profiler instanceof ProfilerStub ) {
1129                 return;
1130         }
1131
1132         if ( isset( $wgDebugLogGroups['profileoutput'] )
1133                 && $wgDebugLogGroups['profileoutput'] === false
1134         ) {
1135                 // Explicitly disabled
1136                 return;
1137         }
1138         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
1139                 return;
1140         }
1141
1142         $ctx = [ 'elapsed' => $request->getElapsedTime() ];
1143         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
1144                 $ctx['forwarded_for'] = $_SERVER['HTTP_X_FORWARDED_FOR'];
1145         }
1146         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
1147                 $ctx['client_ip'] = $_SERVER['HTTP_CLIENT_IP'];
1148         }
1149         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
1150                 $ctx['from'] = $_SERVER['HTTP_FROM'];
1151         }
1152         if ( isset( $ctx['forwarded_for'] ) ||
1153                 isset( $ctx['client_ip'] ) ||
1154                 isset( $ctx['from'] ) ) {
1155                 $ctx['proxy'] = $_SERVER['REMOTE_ADDR'];
1156         }
1157
1158         // Don't load $wgUser at this late stage just for statistics purposes
1159         // @todo FIXME: We can detect some anons even if it is not loaded.
1160         // See User::getId()
1161         $user = $context->getUser();
1162         $ctx['anon'] = $user->isItemLoaded( 'id' ) && $user->isAnon();
1163
1164         // Command line script uses a FauxRequest object which does not have
1165         // any knowledge about an URL and throw an exception instead.
1166         try {
1167                 $ctx['url'] = urldecode( $request->getRequestURL() );
1168         } catch ( Exception $ignored ) {
1169                 // no-op
1170         }
1171
1172         $ctx['output'] = $profiler->getOutput();
1173
1174         $log = LoggerFactory::getInstance( 'profileoutput' );
1175         $log->info( "Elapsed: {elapsed}; URL: <{url}>\n{output}", $ctx );
1176 }
1177
1178 /**
1179  * Increment a statistics counter
1180  *
1181  * @param string $key
1182  * @param int $count
1183  * @return void
1184  */
1185 function wfIncrStats( $key, $count = 1 ) {
1186         $stats = MediaWikiServices::getInstance()->getStatsdDataFactory();
1187         $stats->updateCount( $key, $count );
1188 }
1189
1190 /**
1191  * Check whether the wiki is in read-only mode.
1192  *
1193  * @return bool
1194  */
1195 function wfReadOnly() {
1196         return MediaWikiServices::getInstance()->getReadOnlyMode()
1197                 ->isReadOnly();
1198 }
1199
1200 /**
1201  * Check if the site is in read-only mode and return the message if so
1202  *
1203  * This checks wfConfiguredReadOnlyReason() and the main load balancer
1204  * for replica DB lag. This may result in DB connection being made.
1205  *
1206  * @return string|bool String when in read-only mode; false otherwise
1207  */
1208 function wfReadOnlyReason() {
1209         return MediaWikiServices::getInstance()->getReadOnlyMode()
1210                 ->getReason();
1211 }
1212
1213 /**
1214  * Get the value of $wgReadOnly or the contents of $wgReadOnlyFile.
1215  *
1216  * @return string|bool String when in read-only mode; false otherwise
1217  * @since 1.27
1218  */
1219 function wfConfiguredReadOnlyReason() {
1220         return MediaWikiServices::getInstance()->getConfiguredReadOnlyMode()
1221                 ->getReason();
1222 }
1223
1224 /**
1225  * Return a Language object from $langcode
1226  *
1227  * @param Language|string|bool $langcode Either:
1228  *                  - a Language object
1229  *                  - code of the language to get the message for, if it is
1230  *                    a valid code create a language for that language, if
1231  *                    it is a string but not a valid code then make a basic
1232  *                    language object
1233  *                  - a boolean: if it's false then use the global object for
1234  *                    the current user's language (as a fallback for the old parameter
1235  *                    functionality), or if it is true then use global object
1236  *                    for the wiki's content language.
1237  * @return Language
1238  */
1239 function wfGetLangObj( $langcode = false ) {
1240         # Identify which language to get or create a language object for.
1241         # Using is_object here due to Stub objects.
1242         if ( is_object( $langcode ) ) {
1243                 # Great, we already have the object (hopefully)!
1244                 return $langcode;
1245         }
1246
1247         global $wgLanguageCode;
1248         if ( $langcode === true || $langcode === $wgLanguageCode ) {
1249                 # $langcode is the language code of the wikis content language object.
1250                 # or it is a boolean and value is true
1251                 return MediaWikiServices::getInstance()->getContentLanguage();
1252         }
1253
1254         global $wgLang;
1255         if ( $langcode === false || $langcode === $wgLang->getCode() ) {
1256                 # $langcode is the language code of user language object.
1257                 # or it was a boolean and value is false
1258                 return $wgLang;
1259         }
1260
1261         $validCodes = array_keys( Language::fetchLanguageNames() );
1262         if ( in_array( $langcode, $validCodes ) ) {
1263                 # $langcode corresponds to a valid language.
1264                 return Language::factory( $langcode );
1265         }
1266
1267         # $langcode is a string, but not a valid language code; use content language.
1268         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
1269         return MediaWikiServices::getInstance()->getContentLanguage();
1270 }
1271
1272 /**
1273  * This is the function for getting translated interface messages.
1274  *
1275  * @see Message class for documentation how to use them.
1276  * @see https://www.mediawiki.org/wiki/Manual:Messages_API
1277  *
1278  * This function replaces all old wfMsg* functions.
1279  *
1280  * @param string|string[]|MessageSpecifier $key Message key, or array of keys, or a MessageSpecifier
1281  * @param string|string[] ...$params Normal message parameters
1282  * @return Message
1283  *
1284  * @since 1.17
1285  *
1286  * @see Message::__construct
1287  */
1288 function wfMessage( $key, ...$params ) {
1289         $message = new Message( $key );
1290
1291         // We call Message::params() to reduce code duplication
1292         if ( $params ) {
1293                 $message->params( ...$params );
1294         }
1295
1296         return $message;
1297 }
1298
1299 /**
1300  * This function accepts multiple message keys and returns a message instance
1301  * for the first message which is non-empty. If all messages are empty then an
1302  * instance of the first message key is returned.
1303  *
1304  * @param string ...$keys Message keys
1305  * @return Message
1306  *
1307  * @since 1.18
1308  *
1309  * @see Message::newFallbackSequence
1310  */
1311 function wfMessageFallback( ...$keys ) {
1312         return Message::newFallbackSequence( ...$keys );
1313 }
1314
1315 /**
1316  * Replace message parameter keys on the given formatted output.
1317  *
1318  * @param string $message
1319  * @param array $args
1320  * @return string
1321  * @private
1322  */
1323 function wfMsgReplaceArgs( $message, $args ) {
1324         # Fix windows line-endings
1325         # Some messages are split with explode("\n", $msg)
1326         $message = str_replace( "\r", '', $message );
1327
1328         // Replace arguments
1329         if ( is_array( $args ) && $args ) {
1330                 if ( is_array( $args[0] ) ) {
1331                         $args = array_values( $args[0] );
1332                 }
1333                 $replacementKeys = [];
1334                 foreach ( $args as $n => $param ) {
1335                         $replacementKeys['$' . ( $n + 1 )] = $param;
1336                 }
1337                 $message = strtr( $message, $replacementKeys );
1338         }
1339
1340         return $message;
1341 }
1342
1343 /**
1344  * Fetch server name for use in error reporting etc.
1345  * Use real server name if available, so we know which machine
1346  * in a server farm generated the current page.
1347  *
1348  * @return string
1349  */
1350 function wfHostname() {
1351         static $host;
1352         if ( is_null( $host ) ) {
1353                 # Hostname overriding
1354                 global $wgOverrideHostname;
1355                 if ( $wgOverrideHostname !== false ) {
1356                         # Set static and skip any detection
1357                         $host = $wgOverrideHostname;
1358                         return $host;
1359                 }
1360
1361                 if ( function_exists( 'posix_uname' ) ) {
1362                         // This function not present on Windows
1363                         $uname = posix_uname();
1364                 } else {
1365                         $uname = false;
1366                 }
1367                 if ( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1368                         $host = $uname['nodename'];
1369                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1370                         # Windows computer name
1371                         $host = getenv( 'COMPUTERNAME' );
1372                 } else {
1373                         # This may be a virtual server.
1374                         $host = $_SERVER['SERVER_NAME'];
1375                 }
1376         }
1377         return $host;
1378 }
1379
1380 /**
1381  * Returns a script tag that stores the amount of time it took MediaWiki to
1382  * handle the request in milliseconds as 'wgBackendResponseTime'.
1383  *
1384  * If $wgShowHostnames is true, the script will also set 'wgHostname' to the
1385  * hostname of the server handling the request.
1386  *
1387  * @param string|null $nonce Value from OutputPage::getCSPNonce
1388  * @return string|WrappedString HTML
1389  */
1390 function wfReportTime( $nonce = null ) {
1391         global $wgShowHostnames;
1392
1393         $elapsed = ( microtime( true ) - $_SERVER['REQUEST_TIME_FLOAT'] );
1394         // seconds to milliseconds
1395         $responseTime = round( $elapsed * 1000 );
1396         $reportVars = [ 'wgBackendResponseTime' => $responseTime ];
1397         if ( $wgShowHostnames ) {
1398                 $reportVars['wgHostname'] = wfHostname();
1399         }
1400         return Skin::makeVariablesScript( $reportVars, $nonce );
1401 }
1402
1403 /**
1404  * Safety wrapper for debug_backtrace().
1405  *
1406  * Will return an empty array if debug_backtrace is disabled, otherwise
1407  * the output from debug_backtrace() (trimmed).
1408  *
1409  * @param int $limit This parameter can be used to limit the number of stack frames returned
1410  *
1411  * @return array Array of backtrace information
1412  */
1413 function wfDebugBacktrace( $limit = 0 ) {
1414         static $disabled = null;
1415
1416         if ( is_null( $disabled ) ) {
1417                 $disabled = !function_exists( 'debug_backtrace' );
1418                 if ( $disabled ) {
1419                         wfDebug( "debug_backtrace() is disabled\n" );
1420                 }
1421         }
1422         if ( $disabled ) {
1423                 return [];
1424         }
1425
1426         if ( $limit ) {
1427                 return array_slice( debug_backtrace( DEBUG_BACKTRACE_PROVIDE_OBJECT, $limit + 1 ), 1 );
1428         } else {
1429                 return array_slice( debug_backtrace(), 1 );
1430         }
1431 }
1432
1433 /**
1434  * Get a debug backtrace as a string
1435  *
1436  * @param bool|null $raw If true, the return value is plain text. If false, HTML.
1437  *   Defaults to $wgCommandLineMode if unset.
1438  * @return string
1439  * @since 1.25 Supports $raw parameter.
1440  */
1441 function wfBacktrace( $raw = null ) {
1442         global $wgCommandLineMode;
1443
1444         if ( $raw === null ) {
1445                 $raw = $wgCommandLineMode;
1446         }
1447
1448         if ( $raw ) {
1449                 $frameFormat = "%s line %s calls %s()\n";
1450                 $traceFormat = "%s";
1451         } else {
1452                 $frameFormat = "<li>%s line %s calls %s()</li>\n";
1453                 $traceFormat = "<ul>\n%s</ul>\n";
1454         }
1455
1456         $frames = array_map( function ( $frame ) use ( $frameFormat ) {
1457                 $file = !empty( $frame['file'] ) ? basename( $frame['file'] ) : '-';
1458                 $line = $frame['line'] ?? '-';
1459                 $call = $frame['function'];
1460                 if ( !empty( $frame['class'] ) ) {
1461                         $call = $frame['class'] . $frame['type'] . $call;
1462                 }
1463                 return sprintf( $frameFormat, $file, $line, $call );
1464         }, wfDebugBacktrace() );
1465
1466         return sprintf( $traceFormat, implode( '', $frames ) );
1467 }
1468
1469 /**
1470  * Get the name of the function which called this function
1471  * wfGetCaller( 1 ) is the function with the wfGetCaller() call (ie. __FUNCTION__)
1472  * wfGetCaller( 2 ) [default] is the caller of the function running wfGetCaller()
1473  * wfGetCaller( 3 ) is the parent of that.
1474  *
1475  * @param int $level
1476  * @return string
1477  */
1478 function wfGetCaller( $level = 2 ) {
1479         $backtrace = wfDebugBacktrace( $level + 1 );
1480         if ( isset( $backtrace[$level] ) ) {
1481                 return wfFormatStackFrame( $backtrace[$level] );
1482         } else {
1483                 return 'unknown';
1484         }
1485 }
1486
1487 /**
1488  * Return a string consisting of callers in the stack. Useful sometimes
1489  * for profiling specific points.
1490  *
1491  * @param int $limit The maximum depth of the stack frame to return, or false for the entire stack.
1492  * @return string
1493  */
1494 function wfGetAllCallers( $limit = 3 ) {
1495         $trace = array_reverse( wfDebugBacktrace() );
1496         if ( !$limit || $limit > count( $trace ) - 1 ) {
1497                 $limit = count( $trace ) - 1;
1498         }
1499         $trace = array_slice( $trace, -$limit - 1, $limit );
1500         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1501 }
1502
1503 /**
1504  * Return a string representation of frame
1505  *
1506  * @param array $frame
1507  * @return string
1508  */
1509 function wfFormatStackFrame( $frame ) {
1510         if ( !isset( $frame['function'] ) ) {
1511                 return 'NO_FUNCTION_GIVEN';
1512         }
1513         return isset( $frame['class'] ) && isset( $frame['type'] ) ?
1514                 $frame['class'] . $frame['type'] . $frame['function'] :
1515                 $frame['function'];
1516 }
1517
1518 /* Some generic result counters, pulled out of SearchEngine */
1519
1520 /**
1521  * @todo document
1522  *
1523  * @param int $offset
1524  * @param int $limit
1525  * @return string
1526  */
1527 function wfShowingResults( $offset, $limit ) {
1528         return wfMessage( 'showingresults' )->numParams( $limit, $offset + 1 )->parse();
1529 }
1530
1531 /**
1532  * Whether the client accept gzip encoding
1533  *
1534  * Uses the Accept-Encoding header to check if the client supports gzip encoding.
1535  * Use this when considering to send a gzip-encoded response to the client.
1536  *
1537  * @param bool $force Forces another check even if we already have a cached result.
1538  * @return bool
1539  */
1540 function wfClientAcceptsGzip( $force = false ) {
1541         static $result = null;
1542         if ( $result === null || $force ) {
1543                 $result = false;
1544                 if ( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1545                         # @todo FIXME: We may want to blacklist some broken browsers
1546                         $m = [];
1547                         if ( preg_match(
1548                                         '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1549                                         $_SERVER['HTTP_ACCEPT_ENCODING'],
1550                                         $m
1551                                 )
1552                         ) {
1553                                 if ( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1554                                         $result = false;
1555                                         return $result;
1556                                 }
1557                                 wfDebug( "wfClientAcceptsGzip: client accepts gzip.\n" );
1558                                 $result = true;
1559                         }
1560                 }
1561         }
1562         return $result;
1563 }
1564
1565 /**
1566  * Escapes the given text so that it may be output using addWikiText()
1567  * without any linking, formatting, etc. making its way through. This
1568  * is achieved by substituting certain characters with HTML entities.
1569  * As required by the callers, "<nowiki>" is not used.
1570  *
1571  * @param string $text Text to be escaped
1572  * @param-taint $text escapes_html
1573  * @return string
1574  */
1575 function wfEscapeWikiText( $text ) {
1576         global $wgEnableMagicLinks;
1577         static $repl = null, $repl2 = null;
1578         if ( $repl === null || defined( 'MW_PARSER_TEST' ) || defined( 'MW_PHPUNIT_TEST' ) ) {
1579                 // Tests depend upon being able to change $wgEnableMagicLinks, so don't cache
1580                 // in those situations
1581                 $repl = [
1582                         '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
1583                         '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
1584                         '{' => '&#123;', '|' => '&#124;', '}' => '&#125;', ';' => '&#59;',
1585                         "\n#" => "\n&#35;", "\r#" => "\r&#35;",
1586                         "\n*" => "\n&#42;", "\r*" => "\r&#42;",
1587                         "\n:" => "\n&#58;", "\r:" => "\r&#58;",
1588                         "\n " => "\n&#32;", "\r " => "\r&#32;",
1589                         "\n\n" => "\n&#10;", "\r\n" => "&#13;\n",
1590                         "\n\r" => "\n&#13;", "\r\r" => "\r&#13;",
1591                         "\n\t" => "\n&#9;", "\r\t" => "\r&#9;", // "\n\t\n" is treated like "\n\n"
1592                         "\n----" => "\n&#45;---", "\r----" => "\r&#45;---",
1593                         '__' => '_&#95;', '://' => '&#58;//',
1594                 ];
1595
1596                 $magicLinks = array_keys( array_filter( $wgEnableMagicLinks ) );
1597                 // We have to catch everything "\s" matches in PCRE
1598                 foreach ( $magicLinks as $magic ) {
1599                         $repl["$magic "] = "$magic&#32;";
1600                         $repl["$magic\t"] = "$magic&#9;";
1601                         $repl["$magic\r"] = "$magic&#13;";
1602                         $repl["$magic\n"] = "$magic&#10;";
1603                         $repl["$magic\f"] = "$magic&#12;";
1604                 }
1605
1606                 // And handle protocols that don't use "://"
1607                 global $wgUrlProtocols;
1608                 $repl2 = [];
1609                 foreach ( $wgUrlProtocols as $prot ) {
1610                         if ( substr( $prot, -1 ) === ':' ) {
1611                                 $repl2[] = preg_quote( substr( $prot, 0, -1 ), '/' );
1612                         }
1613                 }
1614                 $repl2 = $repl2 ? '/\b(' . implode( '|', $repl2 ) . '):/i' : '/^(?!)/';
1615         }
1616         $text = substr( strtr( "\n$text", $repl ), 1 );
1617         $text = preg_replace( $repl2, '$1&#58;', $text );
1618         return $text;
1619 }
1620
1621 /**
1622  * Sets dest to source and returns the original value of dest
1623  * If source is NULL, it just returns the value, it doesn't set the variable
1624  * If force is true, it will set the value even if source is NULL
1625  *
1626  * @param mixed &$dest
1627  * @param mixed $source
1628  * @param bool $force
1629  * @return mixed
1630  */
1631 function wfSetVar( &$dest, $source, $force = false ) {
1632         $temp = $dest;
1633         if ( !is_null( $source ) || $force ) {
1634                 $dest = $source;
1635         }
1636         return $temp;
1637 }
1638
1639 /**
1640  * As for wfSetVar except setting a bit
1641  *
1642  * @param int &$dest
1643  * @param int $bit
1644  * @param bool $state
1645  *
1646  * @return bool
1647  */
1648 function wfSetBit( &$dest, $bit, $state = true ) {
1649         $temp = (bool)( $dest & $bit );
1650         if ( !is_null( $state ) ) {
1651                 if ( $state ) {
1652                         $dest |= $bit;
1653                 } else {
1654                         $dest &= ~$bit;
1655                 }
1656         }
1657         return $temp;
1658 }
1659
1660 /**
1661  * A wrapper around the PHP function var_export().
1662  * Either print it or add it to the regular output ($wgOut).
1663  *
1664  * @param mixed $var A PHP variable to dump.
1665  */
1666 function wfVarDump( $var ) {
1667         global $wgOut;
1668         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
1669         if ( headers_sent() || !isset( $wgOut ) || !is_object( $wgOut ) ) {
1670                 print $s;
1671         } else {
1672                 $wgOut->addHTML( $s );
1673         }
1674 }
1675
1676 /**
1677  * Provide a simple HTTP error.
1678  *
1679  * @param int|string $code
1680  * @param string $label
1681  * @param string $desc
1682  */
1683 function wfHttpError( $code, $label, $desc ) {
1684         global $wgOut;
1685         HttpStatus::header( $code );
1686         if ( $wgOut ) {
1687                 $wgOut->disable();
1688                 $wgOut->sendCacheControl();
1689         }
1690
1691         MediaWiki\HeaderCallback::warnIfHeadersSent();
1692         header( 'Content-type: text/html; charset=utf-8' );
1693         print '<!DOCTYPE html>' .
1694                 '<html><head><title>' .
1695                 htmlspecialchars( $label ) .
1696                 '</title></head><body><h1>' .
1697                 htmlspecialchars( $label ) .
1698                 '</h1><p>' .
1699                 nl2br( htmlspecialchars( $desc ) ) .
1700                 "</p></body></html>\n";
1701 }
1702
1703 /**
1704  * Clear away any user-level output buffers, discarding contents.
1705  *
1706  * Suitable for 'starting afresh', for instance when streaming
1707  * relatively large amounts of data without buffering, or wanting to
1708  * output image files without ob_gzhandler's compression.
1709  *
1710  * The optional $resetGzipEncoding parameter controls suppression of
1711  * the Content-Encoding header sent by ob_gzhandler; by default it
1712  * is left. See comments for wfClearOutputBuffers() for why it would
1713  * be used.
1714  *
1715  * Note that some PHP configuration options may add output buffer
1716  * layers which cannot be removed; these are left in place.
1717  *
1718  * @param bool $resetGzipEncoding
1719  */
1720 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
1721         if ( $resetGzipEncoding ) {
1722                 // Suppress Content-Encoding and Content-Length
1723                 // headers from OutputHandler::handle.
1724                 global $wgDisableOutputCompression;
1725                 $wgDisableOutputCompression = true;
1726         }
1727         while ( $status = ob_get_status() ) {
1728                 if ( isset( $status['flags'] ) ) {
1729                         $flags = PHP_OUTPUT_HANDLER_CLEANABLE | PHP_OUTPUT_HANDLER_REMOVABLE;
1730                         $deleteable = ( $status['flags'] & $flags ) === $flags;
1731                 } elseif ( isset( $status['del'] ) ) {
1732                         $deleteable = $status['del'];
1733                 } else {
1734                         // Guess that any PHP-internal setting can't be removed.
1735                         $deleteable = $status['type'] !== 0; /* PHP_OUTPUT_HANDLER_INTERNAL */
1736                 }
1737                 if ( !$deleteable ) {
1738                         // Give up, and hope the result doesn't break
1739                         // output behavior.
1740                         break;
1741                 }
1742                 if ( $status['name'] === 'MediaWikiTestCase::wfResetOutputBuffersBarrier' ) {
1743                         // Unit testing barrier to prevent this function from breaking PHPUnit.
1744                         break;
1745                 }
1746                 if ( !ob_end_clean() ) {
1747                         // Could not remove output buffer handler; abort now
1748                         // to avoid getting in some kind of infinite loop.
1749                         break;
1750                 }
1751                 if ( $resetGzipEncoding ) {
1752                         if ( $status['name'] == 'ob_gzhandler' ) {
1753                                 // Reset the 'Content-Encoding' field set by this handler
1754                                 // so we can start fresh.
1755                                 header_remove( 'Content-Encoding' );
1756                                 break;
1757                         }
1758                 }
1759         }
1760 }
1761
1762 /**
1763  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
1764  *
1765  * Clear away output buffers, but keep the Content-Encoding header
1766  * produced by ob_gzhandler, if any.
1767  *
1768  * This should be used for HTTP 304 responses, where you need to
1769  * preserve the Content-Encoding header of the real result, but
1770  * also need to suppress the output of ob_gzhandler to keep to spec
1771  * and avoid breaking Firefox in rare cases where the headers and
1772  * body are broken over two packets.
1773  */
1774 function wfClearOutputBuffers() {
1775         wfResetOutputBuffers( false );
1776 }
1777
1778 /**
1779  * Converts an Accept-* header into an array mapping string values to quality
1780  * factors
1781  *
1782  * @param string $accept
1783  * @param string $def Default
1784  * @return float[] Associative array of string => float pairs
1785  */
1786 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
1787         # No arg means accept anything (per HTTP spec)
1788         if ( !$accept ) {
1789                 return [ $def => 1.0 ];
1790         }
1791
1792         $prefs = [];
1793
1794         $parts = explode( ',', $accept );
1795
1796         foreach ( $parts as $part ) {
1797                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
1798                 $values = explode( ';', trim( $part ) );
1799                 $match = [];
1800                 if ( count( $values ) == 1 ) {
1801                         $prefs[$values[0]] = 1.0;
1802                 } elseif ( preg_match( '/q\s*=\s*(\d*\.\d+)/', $values[1], $match ) ) {
1803                         $prefs[$values[0]] = floatval( $match[1] );
1804                 }
1805         }
1806
1807         return $prefs;
1808 }
1809
1810 /**
1811  * Checks if a given MIME type matches any of the keys in the given
1812  * array. Basic wildcards are accepted in the array keys.
1813  *
1814  * Returns the matching MIME type (or wildcard) if a match, otherwise
1815  * NULL if no match.
1816  *
1817  * @param string $type
1818  * @param array $avail
1819  * @return string
1820  * @private
1821  */
1822 function mimeTypeMatch( $type, $avail ) {
1823         if ( array_key_exists( $type, $avail ) ) {
1824                 return $type;
1825         } else {
1826                 $mainType = explode( '/', $type )[0];
1827                 if ( array_key_exists( "$mainType/*", $avail ) ) {
1828                         return "$mainType/*";
1829                 } elseif ( array_key_exists( '*/*', $avail ) ) {
1830                         return '*/*';
1831                 } else {
1832                         return null;
1833                 }
1834         }
1835 }
1836
1837 /**
1838  * Returns the 'best' match between a client's requested internet media types
1839  * and the server's list of available types. Each list should be an associative
1840  * array of type to preference (preference is a float between 0.0 and 1.0).
1841  * Wildcards in the types are acceptable.
1842  *
1843  * @param array $cprefs Client's acceptable type list
1844  * @param array $sprefs Server's offered types
1845  * @return string
1846  *
1847  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
1848  * XXX: generalize to negotiate other stuff
1849  */
1850 function wfNegotiateType( $cprefs, $sprefs ) {
1851         $combine = [];
1852
1853         foreach ( array_keys( $sprefs ) as $type ) {
1854                 $subType = explode( '/', $type )[1];
1855                 if ( $subType != '*' ) {
1856                         $ckey = mimeTypeMatch( $type, $cprefs );
1857                         if ( $ckey ) {
1858                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
1859                         }
1860                 }
1861         }
1862
1863         foreach ( array_keys( $cprefs ) as $type ) {
1864                 $subType = explode( '/', $type )[1];
1865                 if ( $subType != '*' && !array_key_exists( $type, $sprefs ) ) {
1866                         $skey = mimeTypeMatch( $type, $sprefs );
1867                         if ( $skey ) {
1868                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
1869                         }
1870                 }
1871         }
1872
1873         $bestq = 0;
1874         $besttype = null;
1875
1876         foreach ( array_keys( $combine ) as $type ) {
1877                 if ( $combine[$type] > $bestq ) {
1878                         $besttype = $type;
1879                         $bestq = $combine[$type];
1880                 }
1881         }
1882
1883         return $besttype;
1884 }
1885
1886 /**
1887  * Reference-counted warning suppression
1888  *
1889  * @deprecated since 1.26, use Wikimedia\suppressWarnings() directly
1890  * @param bool $end
1891  */
1892 function wfSuppressWarnings( $end = false ) {
1893         Wikimedia\suppressWarnings( $end );
1894 }
1895
1896 /**
1897  * @deprecated since 1.26, use Wikimedia\restoreWarnings() directly
1898  * Restore error level to previous value
1899  */
1900 function wfRestoreWarnings() {
1901         Wikimedia\restoreWarnings();
1902 }
1903
1904 /**
1905  * Get a timestamp string in one of various formats
1906  *
1907  * @param mixed $outputtype A timestamp in one of the supported formats, the
1908  *   function will autodetect which format is supplied and act accordingly.
1909  * @param mixed $ts Optional timestamp to convert, default 0 for the current time
1910  * @return string|bool String / false The same date in the format specified in $outputtype or false
1911  */
1912 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
1913         $ret = MWTimestamp::convert( $outputtype, $ts );
1914         if ( $ret === false ) {
1915                 wfDebug( "wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n" );
1916         }
1917         return $ret;
1918 }
1919
1920 /**
1921  * Return a formatted timestamp, or null if input is null.
1922  * For dealing with nullable timestamp columns in the database.
1923  *
1924  * @param int $outputtype
1925  * @param string|null $ts
1926  * @return string
1927  */
1928 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
1929         if ( is_null( $ts ) ) {
1930                 return null;
1931         } else {
1932                 return wfTimestamp( $outputtype, $ts );
1933         }
1934 }
1935
1936 /**
1937  * Convenience function; returns MediaWiki timestamp for the present time.
1938  *
1939  * @return string
1940  */
1941 function wfTimestampNow() {
1942         # return NOW
1943         return MWTimestamp::now( TS_MW );
1944 }
1945
1946 /**
1947  * Check if the operating system is Windows
1948  *
1949  * @return bool True if it's Windows, false otherwise.
1950  */
1951 function wfIsWindows() {
1952         static $isWindows = null;
1953         if ( $isWindows === null ) {
1954                 $isWindows = strtoupper( substr( PHP_OS, 0, 3 ) ) === 'WIN';
1955         }
1956         return $isWindows;
1957 }
1958
1959 /**
1960  * Check if we are running under HHVM
1961  *
1962  * @return bool
1963  */
1964 function wfIsHHVM() {
1965         return defined( 'HHVM_VERSION' );
1966 }
1967
1968 /**
1969  * Check if we are running from the commandline
1970  *
1971  * @since 1.31
1972  * @return bool
1973  */
1974 function wfIsCLI() {
1975         return PHP_SAPI === 'cli' || PHP_SAPI === 'phpdbg';
1976 }
1977
1978 /**
1979  * Tries to get the system directory for temporary files. First
1980  * $wgTmpDirectory is checked, and then the TMPDIR, TMP, and TEMP
1981  * environment variables are then checked in sequence, then
1982  * sys_get_temp_dir(), then upload_tmp_dir from php.ini.
1983  *
1984  * NOTE: When possible, use instead the tmpfile() function to create
1985  * temporary files to avoid race conditions on file creation, etc.
1986  *
1987  * @return string
1988  */
1989 function wfTempDir() {
1990         global $wgTmpDirectory;
1991
1992         if ( $wgTmpDirectory !== false ) {
1993                 return $wgTmpDirectory;
1994         }
1995
1996         return TempFSFile::getUsableTempDirectory();
1997 }
1998
1999 /**
2000  * Make directory, and make all parent directories if they don't exist
2001  *
2002  * @param string $dir Full path to directory to create
2003  * @param int|null $mode Chmod value to use, default is $wgDirectoryMode
2004  * @param string|null $caller Optional caller param for debugging.
2005  * @throws MWException
2006  * @return bool
2007  */
2008 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2009         global $wgDirectoryMode;
2010
2011         if ( FileBackend::isStoragePath( $dir ) ) { // sanity
2012                 throw new MWException( __FUNCTION__ . " given storage path '$dir'." );
2013         }
2014
2015         if ( !is_null( $caller ) ) {
2016                 wfDebug( "$caller: called wfMkdirParents($dir)\n" );
2017         }
2018
2019         if ( strval( $dir ) === '' || is_dir( $dir ) ) {
2020                 return true;
2021         }
2022
2023         $dir = str_replace( [ '\\', '/' ], DIRECTORY_SEPARATOR, $dir );
2024
2025         if ( is_null( $mode ) ) {
2026                 $mode = $wgDirectoryMode;
2027         }
2028
2029         // Turn off the normal warning, we're doing our own below
2030         Wikimedia\suppressWarnings();
2031         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2032         Wikimedia\restoreWarnings();
2033
2034         if ( !$ok ) {
2035                 // directory may have been created on another request since we last checked
2036                 if ( is_dir( $dir ) ) {
2037                         return true;
2038                 }
2039
2040                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2041                 wfLogWarning( sprintf( "failed to mkdir \"%s\" mode 0%o", $dir, $mode ) );
2042         }
2043         return $ok;
2044 }
2045
2046 /**
2047  * Remove a directory and all its content.
2048  * Does not hide error.
2049  * @param string $dir
2050  */
2051 function wfRecursiveRemoveDir( $dir ) {
2052         wfDebug( __FUNCTION__ . "( $dir )\n" );
2053         // taken from https://secure.php.net/manual/en/function.rmdir.php#98622
2054         if ( is_dir( $dir ) ) {
2055                 $objects = scandir( $dir );
2056                 foreach ( $objects as $object ) {
2057                         if ( $object != "." && $object != ".." ) {
2058                                 if ( filetype( $dir . '/' . $object ) == "dir" ) {
2059                                         wfRecursiveRemoveDir( $dir . '/' . $object );
2060                                 } else {
2061                                         unlink( $dir . '/' . $object );
2062                                 }
2063                         }
2064                 }
2065                 reset( $objects );
2066                 rmdir( $dir );
2067         }
2068 }
2069
2070 /**
2071  * @param int $nr The number to format
2072  * @param int $acc The number of digits after the decimal point, default 2
2073  * @param bool $round Whether or not to round the value, default true
2074  * @return string
2075  */
2076 function wfPercent( $nr, $acc = 2, $round = true ) {
2077         $ret = sprintf( "%.${acc}f", $nr );
2078         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2079 }
2080
2081 /**
2082  * Safety wrapper around ini_get() for boolean settings.
2083  * The values returned from ini_get() are pre-normalized for settings
2084  * set via php.ini or php_flag/php_admin_flag... but *not*
2085  * for those set via php_value/php_admin_value.
2086  *
2087  * It's fairly common for people to use php_value instead of php_flag,
2088  * which can leave you with an 'off' setting giving a false positive
2089  * for code that just takes the ini_get() return value as a boolean.
2090  *
2091  * To make things extra interesting, setting via php_value accepts
2092  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2093  * Unrecognized values go false... again opposite PHP's own coercion
2094  * from string to bool.
2095  *
2096  * Luckily, 'properly' set settings will always come back as '0' or '1',
2097  * so we only have to worry about them and the 'improper' settings.
2098  *
2099  * I frickin' hate PHP... :P
2100  *
2101  * @param string $setting
2102  * @return bool
2103  */
2104 function wfIniGetBool( $setting ) {
2105         return wfStringToBool( ini_get( $setting ) );
2106 }
2107
2108 /**
2109  * Convert string value to boolean, when the following are interpreted as true:
2110  * - on
2111  * - true
2112  * - yes
2113  * - Any number, except 0
2114  * All other strings are interpreted as false.
2115  *
2116  * @param string $val
2117  * @return bool
2118  * @since 1.31
2119  */
2120 function wfStringToBool( $val ) {
2121         $val = strtolower( $val );
2122         // 'on' and 'true' can't have whitespace around them, but '1' can.
2123         return $val == 'on'
2124                 || $val == 'true'
2125                 || $val == 'yes'
2126                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2127 }
2128
2129 /**
2130  * Version of escapeshellarg() that works better on Windows.
2131  *
2132  * Originally, this fixed the incorrect use of single quotes on Windows
2133  * (https://bugs.php.net/bug.php?id=26285) and the locale problems on Linux in
2134  * PHP 5.2.6+ (bug backported to earlier distro releases of PHP).
2135  *
2136  * @param string|string[] ...$args strings to escape and glue together,
2137  *  or a single array of strings parameter
2138  * @return string
2139  * @deprecated since 1.30 use MediaWiki\Shell::escape()
2140  */
2141 function wfEscapeShellArg( ...$args ) {
2142         return Shell::escape( ...$args );
2143 }
2144
2145 /**
2146  * Execute a shell command, with time and memory limits mirrored from the PHP
2147  * configuration if supported.
2148  *
2149  * @param string|string[] $cmd If string, a properly shell-escaped command line,
2150  *   or an array of unescaped arguments, in which case each value will be escaped
2151  *   Example:   [ 'convert', '-font', 'font name' ] would produce "'convert' '-font' 'font name'"
2152  * @param null|mixed &$retval Optional, will receive the program's exit code.
2153  *   (non-zero is usually failure). If there is an error from
2154  *   read, select, or proc_open(), this will be set to -1.
2155  * @param array $environ Optional environment variables which should be
2156  *   added to the executed command environment.
2157  * @param array $limits Optional array with limits(filesize, memory, time, walltime)
2158  *   this overwrites the global wgMaxShell* limits.
2159  * @param array $options Array of options:
2160  *   - duplicateStderr: Set this to true to duplicate stderr to stdout,
2161  *     including errors from limit.sh
2162  *   - profileMethod: By default this function will profile based on the calling
2163  *     method. Set this to a string for an alternative method to profile from
2164  *
2165  * @return string Collected stdout as a string
2166  * @deprecated since 1.30 use class MediaWiki\Shell\Shell
2167  */
2168 function wfShellExec( $cmd, &$retval = null, $environ = [],
2169         $limits = [], $options = []
2170 ) {
2171         if ( Shell::isDisabled() ) {
2172                 $retval = 1;
2173                 // Backwards compatibility be upon us...
2174                 return 'Unable to run external programs, proc_open() is disabled.';
2175         }
2176
2177         if ( is_array( $cmd ) ) {
2178                 $cmd = Shell::escape( $cmd );
2179         }
2180
2181         $includeStderr = isset( $options['duplicateStderr'] ) && $options['duplicateStderr'];
2182         $profileMethod = $options['profileMethod'] ?? wfGetCaller();
2183
2184         try {
2185                 $result = Shell::command( [] )
2186                         ->unsafeParams( (array)$cmd )
2187                         ->environment( $environ )
2188                         ->limits( $limits )
2189                         ->includeStderr( $includeStderr )
2190                         ->profileMethod( $profileMethod )
2191                         // For b/c
2192                         ->restrict( Shell::RESTRICT_NONE )
2193                         ->execute();
2194         } catch ( ProcOpenError $ex ) {
2195                 $retval = -1;
2196                 return '';
2197         }
2198
2199         $retval = $result->getExitCode();
2200
2201         return $result->getStdout();
2202 }
2203
2204 /**
2205  * Execute a shell command, returning both stdout and stderr. Convenience
2206  * function, as all the arguments to wfShellExec can become unwieldy.
2207  *
2208  * @note This also includes errors from limit.sh, e.g. if $wgMaxShellFileSize is exceeded.
2209  * @param string|string[] $cmd If string, a properly shell-escaped command line,
2210  *   or an array of unescaped arguments, in which case each value will be escaped
2211  *   Example:   [ 'convert', '-font', 'font name' ] would produce "'convert' '-font' 'font name'"
2212  * @param null|mixed &$retval Optional, will receive the program's exit code.
2213  *   (non-zero is usually failure)
2214  * @param array $environ Optional environment variables which should be
2215  *   added to the executed command environment.
2216  * @param array $limits Optional array with limits(filesize, memory, time, walltime)
2217  *   this overwrites the global wgMaxShell* limits.
2218  * @return string Collected stdout and stderr as a string
2219  * @deprecated since 1.30 use class MediaWiki\Shell\Shell
2220  */
2221 function wfShellExecWithStderr( $cmd, &$retval = null, $environ = [], $limits = [] ) {
2222         return wfShellExec( $cmd, $retval, $environ, $limits,
2223                 [ 'duplicateStderr' => true, 'profileMethod' => wfGetCaller() ] );
2224 }
2225
2226 /**
2227  * Generate a shell-escaped command line string to run a MediaWiki cli script.
2228  * Note that $parameters should be a flat array and an option with an argument
2229  * should consist of two consecutive items in the array (do not use "--option value").
2230  *
2231  * @deprecated since 1.31, use Shell::makeScriptCommand()
2232  *
2233  * @param string $script MediaWiki cli script path
2234  * @param array $parameters Arguments and options to the script
2235  * @param array $options Associative array of options:
2236  *     'php': The path to the php executable
2237  *     'wrapper': Path to a PHP wrapper to handle the maintenance script
2238  * @return string
2239  */
2240 function wfShellWikiCmd( $script, array $parameters = [], array $options = [] ) {
2241         global $wgPhpCli;
2242         // Give site config file a chance to run the script in a wrapper.
2243         // The caller may likely want to call wfBasename() on $script.
2244         Hooks::run( 'wfShellWikiCmd', [ &$script, &$parameters, &$options ] );
2245         $cmd = [ $options['php'] ?? $wgPhpCli ];
2246         if ( isset( $options['wrapper'] ) ) {
2247                 $cmd[] = $options['wrapper'];
2248         }
2249         $cmd[] = $script;
2250         // Escape each parameter for shell
2251         return Shell::escape( array_merge( $cmd, $parameters ) );
2252 }
2253
2254 /**
2255  * wfMerge attempts to merge differences between three texts.
2256  * Returns true for a clean merge and false for failure or a conflict.
2257  *
2258  * @param string $old
2259  * @param string $mine
2260  * @param string $yours
2261  * @param string &$result
2262  * @param string|null &$mergeAttemptResult
2263  * @return bool
2264  */
2265 function wfMerge( $old, $mine, $yours, &$result, &$mergeAttemptResult = null ) {
2266         global $wgDiff3;
2267
2268         # This check may also protect against code injection in
2269         # case of broken installations.
2270         Wikimedia\suppressWarnings();
2271         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
2272         Wikimedia\restoreWarnings();
2273
2274         if ( !$haveDiff3 ) {
2275                 wfDebug( "diff3 not found\n" );
2276                 return false;
2277         }
2278
2279         # Make temporary files
2280         $td = wfTempDir();
2281         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
2282         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
2283         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
2284
2285         # NOTE: diff3 issues a warning to stderr if any of the files does not end with
2286         #       a newline character. To avoid this, we normalize the trailing whitespace before
2287         #       creating the diff.
2288
2289         fwrite( $oldtextFile, rtrim( $old ) . "\n" );
2290         fclose( $oldtextFile );
2291         fwrite( $mytextFile, rtrim( $mine ) . "\n" );
2292         fclose( $mytextFile );
2293         fwrite( $yourtextFile, rtrim( $yours ) . "\n" );
2294         fclose( $yourtextFile );
2295
2296         # Check for a conflict
2297         $cmd = Shell::escape( $wgDiff3, '-a', '--overlap-only', $mytextName,
2298                 $oldtextName, $yourtextName );
2299         $handle = popen( $cmd, 'r' );
2300
2301         $mergeAttemptResult = '';
2302         do {
2303                 $data = fread( $handle, 8192 );
2304                 if ( strlen( $data ) == 0 ) {
2305                         break;
2306                 }
2307                 $mergeAttemptResult .= $data;
2308         } while ( true );
2309         pclose( $handle );
2310
2311         $conflict = $mergeAttemptResult !== '';
2312
2313         # Merge differences
2314         $cmd = Shell::escape( $wgDiff3, '-a', '-e', '--merge', $mytextName,
2315                 $oldtextName, $yourtextName );
2316         $handle = popen( $cmd, 'r' );
2317         $result = '';
2318         do {
2319                 $data = fread( $handle, 8192 );
2320                 if ( strlen( $data ) == 0 ) {
2321                         break;
2322                 }
2323                 $result .= $data;
2324         } while ( true );
2325         pclose( $handle );
2326         unlink( $mytextName );
2327         unlink( $oldtextName );
2328         unlink( $yourtextName );
2329
2330         if ( $result === '' && $old !== '' && !$conflict ) {
2331                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
2332                 $conflict = true;
2333         }
2334         return !$conflict;
2335 }
2336
2337 /**
2338  * Returns unified plain-text diff of two texts.
2339  * "Useful" for machine processing of diffs.
2340  *
2341  * @deprecated since 1.25, use DiffEngine/UnifiedDiffFormatter directly
2342  *
2343  * @param string $before The text before the changes.
2344  * @param string $after The text after the changes.
2345  * @param string $params Command-line options for the diff command.
2346  * @return string Unified diff of $before and $after
2347  */
2348 function wfDiff( $before, $after, $params = '-u' ) {
2349         if ( $before == $after ) {
2350                 return '';
2351         }
2352
2353         global $wgDiff;
2354         Wikimedia\suppressWarnings();
2355         $haveDiff = $wgDiff && file_exists( $wgDiff );
2356         Wikimedia\restoreWarnings();
2357
2358         # This check may also protect against code injection in
2359         # case of broken installations.
2360         if ( !$haveDiff ) {
2361                 wfDebug( "diff executable not found\n" );
2362                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
2363                 $format = new UnifiedDiffFormatter();
2364                 return $format->format( $diffs );
2365         }
2366
2367         # Make temporary files
2368         $td = wfTempDir();
2369         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
2370         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
2371
2372         fwrite( $oldtextFile, $before );
2373         fclose( $oldtextFile );
2374         fwrite( $newtextFile, $after );
2375         fclose( $newtextFile );
2376
2377         // Get the diff of the two files
2378         $cmd = "$wgDiff " . $params . ' ' . Shell::escape( $oldtextName, $newtextName );
2379
2380         $h = popen( $cmd, 'r' );
2381         if ( !$h ) {
2382                 unlink( $oldtextName );
2383                 unlink( $newtextName );
2384                 throw new Exception( __METHOD__ . '(): popen() failed' );
2385         }
2386
2387         $diff = '';
2388
2389         do {
2390                 $data = fread( $h, 8192 );
2391                 if ( strlen( $data ) == 0 ) {
2392                         break;
2393                 }
2394                 $diff .= $data;
2395         } while ( true );
2396
2397         // Clean up
2398         pclose( $h );
2399         unlink( $oldtextName );
2400         unlink( $newtextName );
2401
2402         // Kill the --- and +++ lines. They're not useful.
2403         $diff_lines = explode( "\n", $diff );
2404         if ( isset( $diff_lines[0] ) && strpos( $diff_lines[0], '---' ) === 0 ) {
2405                 unset( $diff_lines[0] );
2406         }
2407         if ( isset( $diff_lines[1] ) && strpos( $diff_lines[1], '+++' ) === 0 ) {
2408                 unset( $diff_lines[1] );
2409         }
2410
2411         $diff = implode( "\n", $diff_lines );
2412
2413         return $diff;
2414 }
2415
2416 /**
2417  * Return the final portion of a pathname.
2418  * Reimplemented because PHP5's "basename()" is buggy with multibyte text.
2419  * https://bugs.php.net/bug.php?id=33898
2420  *
2421  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
2422  * We'll consider it so always, as we don't want '\s' in our Unix paths either.
2423  *
2424  * @param string $path
2425  * @param string $suffix String to remove if present
2426  * @return string
2427  */
2428 function wfBaseName( $path, $suffix = '' ) {
2429         if ( $suffix == '' ) {
2430                 $encSuffix = '';
2431         } else {
2432                 $encSuffix = '(?:' . preg_quote( $suffix, '#' ) . ')?';
2433         }
2434
2435         $matches = [];
2436         if ( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2437                 return $matches[1];
2438         } else {
2439                 return '';
2440         }
2441 }
2442
2443 /**
2444  * Generate a relative path name to the given file.
2445  * May explode on non-matching case-insensitive paths,
2446  * funky symlinks, etc.
2447  *
2448  * @param string $path Absolute destination path including target filename
2449  * @param string $from Absolute source path, directory only
2450  * @return string
2451  */
2452 function wfRelativePath( $path, $from ) {
2453         // Normalize mixed input on Windows...
2454         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2455         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2456
2457         // Trim trailing slashes -- fix for drive root
2458         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2459         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2460
2461         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2462         $against = explode( DIRECTORY_SEPARATOR, $from );
2463
2464         if ( $pieces[0] !== $against[0] ) {
2465                 // Non-matching Windows drive letters?
2466                 // Return a full path.
2467                 return $path;
2468         }
2469
2470         // Trim off common prefix
2471         while ( count( $pieces ) && count( $against )
2472                 && $pieces[0] == $against[0] ) {
2473                 array_shift( $pieces );
2474                 array_shift( $against );
2475         }
2476
2477         // relative dots to bump us to the parent
2478         while ( count( $against ) ) {
2479                 array_unshift( $pieces, '..' );
2480                 array_shift( $against );
2481         }
2482
2483         array_push( $pieces, wfBaseName( $path ) );
2484
2485         return implode( DIRECTORY_SEPARATOR, $pieces );
2486 }
2487
2488 /**
2489  * Reset the session id
2490  *
2491  * @deprecated since 1.27, use MediaWiki\Session\SessionManager instead
2492  * @since 1.22
2493  */
2494 function wfResetSessionID() {
2495         wfDeprecated( __FUNCTION__, '1.27' );
2496         $session = SessionManager::getGlobalSession();
2497         $delay = $session->delaySave();
2498
2499         $session->resetId();
2500
2501         // Make sure a session is started, since that's what the old
2502         // wfResetSessionID() did.
2503         if ( session_id() !== $session->getId() ) {
2504                 wfSetupSession( $session->getId() );
2505         }
2506
2507         ScopedCallback::consume( $delay );
2508 }
2509
2510 /**
2511  * Initialise php session
2512  *
2513  * @deprecated since 1.27, use MediaWiki\Session\SessionManager instead.
2514  *  Generally, "using" SessionManager will be calling ->getSessionById() or
2515  *  ::getGlobalSession() (depending on whether you were passing $sessionId
2516  *  here), then calling $session->persist().
2517  * @param bool|string $sessionId
2518  */
2519 function wfSetupSession( $sessionId = false ) {
2520         wfDeprecated( __FUNCTION__, '1.27' );
2521
2522         if ( $sessionId ) {
2523                 session_id( $sessionId );
2524         }
2525
2526         $session = SessionManager::getGlobalSession();
2527         $session->persist();
2528
2529         if ( session_id() !== $session->getId() ) {
2530                 session_id( $session->getId() );
2531         }
2532         Wikimedia\quietCall( 'session_start' );
2533 }
2534
2535 /**
2536  * Get an object from the precompiled serialized directory
2537  *
2538  * @param string $name
2539  * @return mixed The variable on success, false on failure
2540  */
2541 function wfGetPrecompiledData( $name ) {
2542         global $IP;
2543
2544         $file = "$IP/serialized/$name";
2545         if ( file_exists( $file ) ) {
2546                 $blob = file_get_contents( $file );
2547                 if ( $blob ) {
2548                         return unserialize( $blob );
2549                 }
2550         }
2551         return false;
2552 }
2553
2554 /**
2555  * Make a cache key for the local wiki.
2556  *
2557  * @deprecated since 1.30 Call makeKey on a BagOStuff instance
2558  * @param string ...$args
2559  * @return string
2560  */
2561 function wfMemcKey( ...$args ) {
2562         return ObjectCache::getLocalClusterInstance()->makeKey( ...$args );
2563 }
2564
2565 /**
2566  * Make a cache key for a foreign DB.
2567  *
2568  * Must match what wfMemcKey() would produce in context of the foreign wiki.
2569  *
2570  * @param string $db
2571  * @param string $prefix
2572  * @param string ...$args
2573  * @return string
2574  */
2575 function wfForeignMemcKey( $db, $prefix, ...$args ) {
2576         $keyspace = $prefix ? "$db-$prefix" : $db;
2577         return ObjectCache::getLocalClusterInstance()->makeKeyInternal( $keyspace, $args );
2578 }
2579
2580 /**
2581  * Make a cache key with database-agnostic prefix.
2582  *
2583  * Doesn't have a wiki-specific namespace. Uses a generic 'global' prefix
2584  * instead. Must have a prefix as otherwise keys that use a database name
2585  * in the first segment will clash with wfMemcKey/wfForeignMemcKey.
2586  *
2587  * @deprecated since 1.30 Call makeGlobalKey on a BagOStuff instance
2588  * @since 1.26
2589  * @param string ...$args
2590  * @return string
2591  */
2592 function wfGlobalCacheKey( ...$args ) {
2593         return ObjectCache::getLocalClusterInstance()->makeGlobalKey( ...$args );
2594 }
2595
2596 /**
2597  * Get an ASCII string identifying this wiki
2598  * This is used as a prefix in memcached keys
2599  *
2600  * @return string
2601  */
2602 function wfWikiID() {
2603         global $wgDBprefix, $wgDBname;
2604         if ( $wgDBprefix ) {
2605                 return "$wgDBname-$wgDBprefix";
2606         } else {
2607                 return $wgDBname;
2608         }
2609 }
2610
2611 /**
2612  * Split a wiki ID into DB name and table prefix
2613  *
2614  * @param string $wiki
2615  *
2616  * @return array
2617  * @deprecated 1.32
2618  */
2619 function wfSplitWikiID( $wiki ) {
2620         $bits = explode( '-', $wiki, 2 );
2621         if ( count( $bits ) < 2 ) {
2622                 $bits[] = '';
2623         }
2624         return $bits;
2625 }
2626
2627 /**
2628  * Get a Database object.
2629  *
2630  * @param int $db Index of the connection to get. May be DB_MASTER for the
2631  *            master (for write queries), DB_REPLICA for potentially lagged read
2632  *            queries, or an integer >= 0 for a particular server.
2633  *
2634  * @param string|string[] $groups Query groups. An array of group names that this query
2635  *                belongs to. May contain a single string if the query is only
2636  *                in one group.
2637  *
2638  * @param string|bool $wiki The wiki ID, or false for the current wiki
2639  *
2640  * Note: multiple calls to wfGetDB(DB_REPLICA) during the course of one request
2641  * will always return the same object, unless the underlying connection or load
2642  * balancer is manually destroyed.
2643  *
2644  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
2645  * updater to ensure that a proper database is being updated.
2646  *
2647  * @todo Replace calls to wfGetDB with calls to LoadBalancer::getConnection()
2648  *       on an injected instance of LoadBalancer.
2649  *
2650  * @return \Wikimedia\Rdbms\Database
2651  */
2652 function wfGetDB( $db, $groups = [], $wiki = false ) {
2653         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
2654 }
2655
2656 /**
2657  * Get a load balancer object.
2658  *
2659  * @deprecated since 1.27, use MediaWikiServices::getDBLoadBalancer()
2660  *              or MediaWikiServices::getDBLoadBalancerFactory() instead.
2661  *
2662  * @param string|bool $wiki Wiki ID, or false for the current wiki
2663  * @return \Wikimedia\Rdbms\LoadBalancer
2664  */
2665 function wfGetLB( $wiki = false ) {
2666         if ( $wiki === false ) {
2667                 return MediaWikiServices::getInstance()->getDBLoadBalancer();
2668         } else {
2669                 $factory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
2670                 return $factory->getMainLB( $wiki );
2671         }
2672 }
2673
2674 /**
2675  * Get the load balancer factory object
2676  *
2677  * @deprecated since 1.27, use MediaWikiServices::getDBLoadBalancerFactory() instead.
2678  *
2679  * @return \Wikimedia\Rdbms\LBFactory
2680  */
2681 function wfGetLBFactory() {
2682         return MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
2683 }
2684
2685 /**
2686  * Find a file.
2687  * Shortcut for RepoGroup::singleton()->findFile()
2688  *
2689  * @param string|Title $title String or Title object
2690  * @param array $options Associative array of options (see RepoGroup::findFile)
2691  * @return File|bool File, or false if the file does not exist
2692  */
2693 function wfFindFile( $title, $options = [] ) {
2694         return RepoGroup::singleton()->findFile( $title, $options );
2695 }
2696
2697 /**
2698  * Get an object referring to a locally registered file.
2699  * Returns a valid placeholder object if the file does not exist.
2700  *
2701  * @param Title|string $title
2702  * @return LocalFile|null A File, or null if passed an invalid Title
2703  */
2704 function wfLocalFile( $title ) {
2705         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
2706 }
2707
2708 /**
2709  * Should low-performance queries be disabled?
2710  *
2711  * @return bool
2712  * @codeCoverageIgnore
2713  */
2714 function wfQueriesMustScale() {
2715         global $wgMiserMode;
2716         return $wgMiserMode
2717                 || ( SiteStats::pages() > 100000
2718                 && SiteStats::edits() > 1000000
2719                 && SiteStats::users() > 10000 );
2720 }
2721
2722 /**
2723  * Get the path to a specified script file, respecting file
2724  * extensions; this is a wrapper around $wgScriptPath etc.
2725  * except for 'index' and 'load' which use $wgScript/$wgLoadScript
2726  *
2727  * @param string $script Script filename, sans extension
2728  * @return string
2729  */
2730 function wfScript( $script = 'index' ) {
2731         global $wgScriptPath, $wgScript, $wgLoadScript;
2732         if ( $script === 'index' ) {
2733                 return $wgScript;
2734         } elseif ( $script === 'load' ) {
2735                 return $wgLoadScript;
2736         } else {
2737                 return "{$wgScriptPath}/{$script}.php";
2738         }
2739 }
2740
2741 /**
2742  * Get the script URL.
2743  *
2744  * @return string Script URL
2745  */
2746 function wfGetScriptUrl() {
2747         if ( isset( $_SERVER['SCRIPT_NAME'] ) ) {
2748                 /* as it was called, minus the query string.
2749                  *
2750                  * Some sites use Apache rewrite rules to handle subdomains,
2751                  * and have PHP set up in a weird way that causes PHP_SELF
2752                  * to contain the rewritten URL instead of the one that the
2753                  * outside world sees.
2754                  *
2755                  * If in this mode, use SCRIPT_URL instead, which mod_rewrite
2756                  * provides containing the "before" URL.
2757                  */
2758                 return $_SERVER['SCRIPT_NAME'];
2759         } else {
2760                 return $_SERVER['URL'];
2761         }
2762 }
2763
2764 /**
2765  * Convenience function converts boolean values into "true"
2766  * or "false" (string) values
2767  *
2768  * @param bool $value
2769  * @return string
2770  */
2771 function wfBoolToStr( $value ) {
2772         return $value ? 'true' : 'false';
2773 }
2774
2775 /**
2776  * Get a platform-independent path to the null file, e.g. /dev/null
2777  *
2778  * @return string
2779  */
2780 function wfGetNull() {
2781         return wfIsWindows() ? 'NUL' : '/dev/null';
2782 }
2783
2784 /**
2785  * Waits for the replica DBs to catch up to the master position
2786  *
2787  * Use this when updating very large numbers of rows, as in maintenance scripts,
2788  * to avoid causing too much lag. Of course, this is a no-op if there are no replica DBs.
2789  *
2790  * By default this waits on the main DB cluster of the current wiki.
2791  * If $cluster is set to "*" it will wait on all DB clusters, including
2792  * external ones. If the lag being waiting on is caused by the code that
2793  * does this check, it makes since to use $ifWritesSince, particularly if
2794  * cluster is "*", to avoid excess overhead.
2795  *
2796  * Never call this function after a big DB write that is still in a transaction.
2797  * This only makes sense after the possible lag inducing changes were committed.
2798  *
2799  * @param float|null $ifWritesSince Only wait if writes were done since this UNIX timestamp
2800  * @param string|bool $wiki Wiki identifier accepted by wfGetLB
2801  * @param string|bool $cluster Cluster name accepted by LBFactory. Default: false.
2802  * @param int|null $timeout Max wait time. Default: 60 seconds (cli), 1 second (web)
2803  * @return bool Success (able to connect and no timeouts reached)
2804  * @deprecated since 1.27 Use LBFactory::waitForReplication
2805  */
2806 function wfWaitForSlaves(
2807         $ifWritesSince = null, $wiki = false, $cluster = false, $timeout = null
2808 ) {
2809         $lbFactory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
2810
2811         if ( $cluster === '*' ) {
2812                 $cluster = false;
2813                 $domain = false;
2814         } elseif ( $wiki === false ) {
2815                 $domain = $lbFactory->getLocalDomainID();
2816         } else {
2817                 $domain = $wiki;
2818         }
2819
2820         $opts = [
2821                 'domain' => $domain,
2822                 'cluster' => $cluster,
2823                 // B/C: first argument used to be "max seconds of lag"; ignore such values
2824                 'ifWritesSince' => ( $ifWritesSince > 1e9 ) ? $ifWritesSince : null
2825         ];
2826         if ( $timeout !== null ) {
2827                 $opts['timeout'] = $timeout;
2828         }
2829
2830         return $lbFactory->waitForReplication( $opts );
2831 }
2832
2833 /**
2834  * Count down from $seconds to zero on the terminal, with a one-second pause
2835  * between showing each number. For use in command-line scripts.
2836  *
2837  * @deprecated since 1.31, use Maintenance::countDown()
2838  *
2839  * @codeCoverageIgnore
2840  * @param int $seconds
2841  */
2842 function wfCountDown( $seconds ) {
2843         wfDeprecated( __FUNCTION__, '1.31' );
2844         for ( $i = $seconds; $i >= 0; $i-- ) {
2845                 if ( $i != $seconds ) {
2846                         echo str_repeat( "\x08", strlen( $i + 1 ) );
2847                 }
2848                 echo $i;
2849                 flush();
2850                 if ( $i ) {
2851                         sleep( 1 );
2852                 }
2853         }
2854         echo "\n";
2855 }
2856
2857 /**
2858  * Replace all invalid characters with '-'.
2859  * Additional characters can be defined in $wgIllegalFileChars (see T22489).
2860  * By default, $wgIllegalFileChars includes ':', '/', '\'.
2861  *
2862  * @param string $name Filename to process
2863  * @return string
2864  */
2865 function wfStripIllegalFilenameChars( $name ) {
2866         global $wgIllegalFileChars;
2867         $illegalFileChars = $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '';
2868         $name = preg_replace(
2869                 "/[^" . Title::legalChars() . "]" . $illegalFileChars . "/",
2870                 '-',
2871                 $name
2872         );
2873         // $wgIllegalFileChars may not include '/' and '\', so we still need to do this
2874         $name = wfBaseName( $name );
2875         return $name;
2876 }
2877
2878 /**
2879  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit
2880  *
2881  * @return int Resulting value of the memory limit.
2882  */
2883 function wfMemoryLimit() {
2884         global $wgMemoryLimit;
2885         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
2886         if ( $memlimit != -1 ) {
2887                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
2888                 if ( $conflimit == -1 ) {
2889                         wfDebug( "Removing PHP's memory limit\n" );
2890                         Wikimedia\suppressWarnings();
2891                         ini_set( 'memory_limit', $conflimit );
2892                         Wikimedia\restoreWarnings();
2893                         return $conflimit;
2894                 } elseif ( $conflimit > $memlimit ) {
2895                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
2896                         Wikimedia\suppressWarnings();
2897                         ini_set( 'memory_limit', $conflimit );
2898                         Wikimedia\restoreWarnings();
2899                         return $conflimit;
2900                 }
2901         }
2902         return $memlimit;
2903 }
2904
2905 /**
2906  * Set PHP's time limit to the larger of php.ini or $wgTransactionalTimeLimit
2907  *
2908  * @return int Prior time limit
2909  * @since 1.26
2910  */
2911 function wfTransactionalTimeLimit() {
2912         global $wgTransactionalTimeLimit;
2913
2914         $timeLimit = ini_get( 'max_execution_time' );
2915         // Note that CLI scripts use 0
2916         if ( $timeLimit > 0 && $wgTransactionalTimeLimit > $timeLimit ) {
2917                 set_time_limit( $wgTransactionalTimeLimit );
2918         }
2919
2920         ignore_user_abort( true ); // ignore client disconnects
2921
2922         return $timeLimit;
2923 }
2924
2925 /**
2926  * Converts shorthand byte notation to integer form
2927  *
2928  * @param string $string
2929  * @param int $default Returned if $string is empty
2930  * @return int
2931  */
2932 function wfShorthandToInteger( $string = '', $default = -1 ) {
2933         $string = trim( $string );
2934         if ( $string === '' ) {
2935                 return $default;
2936         }
2937         $last = $string[strlen( $string ) - 1];
2938         $val = intval( $string );
2939         switch ( $last ) {
2940                 case 'g':
2941                 case 'G':
2942                         $val *= 1024;
2943                         // break intentionally missing
2944                 case 'm':
2945                 case 'M':
2946                         $val *= 1024;
2947                         // break intentionally missing
2948                 case 'k':
2949                 case 'K':
2950                         $val *= 1024;
2951         }
2952
2953         return $val;
2954 }
2955
2956 /**
2957  * Get the normalised IETF language tag
2958  * See unit test for examples.
2959  * See mediawiki.language.bcp47 for the JavaScript implementation.
2960  *
2961  * @deprecated since 1.31, use LanguageCode::bcp47() directly.
2962  *
2963  * @param string $code The language code.
2964  * @return string The language code which complying with BCP 47 standards.
2965  */
2966 function wfBCP47( $code ) {
2967         wfDeprecated( __METHOD__, '1.31' );
2968         return LanguageCode::bcp47( $code );
2969 }
2970
2971 /**
2972  * Get a specific cache object.
2973  *
2974  * @deprecated since 1.32, use ObjectCache::getInstance() instead
2975  * @param int|string $cacheType A CACHE_* constants, or other key in $wgObjectCaches
2976  * @return BagOStuff
2977  */
2978 function wfGetCache( $cacheType ) {
2979         return ObjectCache::getInstance( $cacheType );
2980 }
2981
2982 /**
2983  * Get the main cache object
2984  *
2985  * @deprecated since 1.32, use ObjectCache::getLocalClusterInstance() instead
2986  * @return BagOStuff
2987  */
2988 function wfGetMainCache() {
2989         return ObjectCache::getLocalClusterInstance();
2990 }
2991
2992 /**
2993  * Get the cache object used by the message cache
2994  *
2995  * @return BagOStuff
2996  */
2997 function wfGetMessageCacheStorage() {
2998         global $wgMessageCacheType;
2999         return ObjectCache::getInstance( $wgMessageCacheType );
3000 }
3001
3002 /**
3003  * Wrapper around php's unpack.
3004  *
3005  * @param string $format The format string (See php's docs)
3006  * @param string $data A binary string of binary data
3007  * @param int|bool $length The minimum length of $data or false. This is to
3008  *      prevent reading beyond the end of $data. false to disable the check.
3009  *
3010  * Also be careful when using this function to read unsigned 32 bit integer
3011  * because php might make it negative.
3012  *
3013  * @throws MWException If $data not long enough, or if unpack fails
3014  * @return array Associative array of the extracted data
3015  */
3016 function wfUnpack( $format, $data, $length = false ) {
3017         if ( $length !== false ) {
3018                 $realLen = strlen( $data );
3019                 if ( $realLen < $length ) {
3020                         throw new MWException( "Tried to use wfUnpack on a "
3021                                 . "string of length $realLen, but needed one "
3022                                 . "of at least length $length."
3023                         );
3024                 }
3025         }
3026
3027         Wikimedia\suppressWarnings();
3028         $result = unpack( $format, $data );
3029         Wikimedia\restoreWarnings();
3030
3031         if ( $result === false ) {
3032                 // If it cannot extract the packed data.
3033                 throw new MWException( "unpack could not unpack binary data" );
3034         }
3035         return $result;
3036 }
3037
3038 /**
3039  * Determine if an image exists on the 'bad image list'.
3040  *
3041  * The format of MediaWiki:Bad_image_list is as follows:
3042  *    * Only list items (lines starting with "*") are considered
3043  *    * The first link on a line must be a link to a bad image
3044  *    * Any subsequent links on the same line are considered to be exceptions,
3045  *      i.e. articles where the image may occur inline.
3046  *
3047  * @param string $name The image name to check
3048  * @param Title|bool $contextTitle The page on which the image occurs, if known
3049  * @param string|null $blacklist Wikitext of a file blacklist
3050  * @return bool
3051  */
3052 function wfIsBadImage( $name, $contextTitle = false, $blacklist = null ) {
3053         # Handle redirects; callers almost always hit wfFindFile() anyway,
3054         # so just use that method because it has a fast process cache.
3055         $file = wfFindFile( $name ); // get the final name
3056         $name = $file ? $file->getTitle()->getDBkey() : $name;
3057
3058         # Run the extension hook
3059         $bad = false;
3060         if ( !Hooks::run( 'BadImage', [ $name, &$bad ] ) ) {
3061                 return (bool)$bad;
3062         }
3063
3064         $cache = ObjectCache::getLocalServerInstance( 'hash' );
3065         $key = $cache->makeKey(
3066                 'bad-image-list', ( $blacklist === null ) ? 'default' : md5( $blacklist )
3067         );
3068         $badImages = $cache->get( $key );
3069
3070         if ( $badImages === false ) { // cache miss
3071                 if ( $blacklist === null ) {
3072                         $blacklist = wfMessage( 'bad_image_list' )->inContentLanguage()->plain(); // site list
3073                 }
3074                 # Build the list now
3075                 $badImages = [];
3076                 $lines = explode( "\n", $blacklist );
3077                 foreach ( $lines as $line ) {
3078                         # List items only
3079                         if ( substr( $line, 0, 1 ) !== '*' ) {
3080                                 continue;
3081                         }
3082
3083                         # Find all links
3084                         $m = [];
3085                         if ( !preg_match_all( '/\[\[:?(.*?)\]\]/', $line, $m ) ) {
3086                                 continue;
3087                         }
3088
3089                         $exceptions = [];
3090                         $imageDBkey = false;
3091                         foreach ( $m[1] as $i => $titleText ) {
3092                                 $title = Title::newFromText( $titleText );
3093                                 if ( !is_null( $title ) ) {
3094                                         if ( $i == 0 ) {
3095                                                 $imageDBkey = $title->getDBkey();
3096                                         } else {
3097                                                 $exceptions[$title->getPrefixedDBkey()] = true;
3098                                         }
3099                                 }
3100                         }
3101
3102                         if ( $imageDBkey !== false ) {
3103                                 $badImages[$imageDBkey] = $exceptions;
3104                         }
3105                 }
3106                 $cache->set( $key, $badImages, 60 );
3107         }
3108
3109         $contextKey = $contextTitle ? $contextTitle->getPrefixedDBkey() : false;
3110         $bad = isset( $badImages[$name] ) && !isset( $badImages[$name][$contextKey] );
3111
3112         return $bad;
3113 }
3114
3115 /**
3116  * Determine whether the client at a given source IP is likely to be able to
3117  * access the wiki via HTTPS.
3118  *
3119  * @param string $ip The IPv4/6 address in the normal human-readable form
3120  * @return bool
3121  */
3122 function wfCanIPUseHTTPS( $ip ) {
3123         $canDo = true;
3124         Hooks::run( 'CanIPUseHTTPS', [ $ip, &$canDo ] );
3125         return !!$canDo;
3126 }
3127
3128 /**
3129  * Determine input string is represents as infinity
3130  *
3131  * @param string $str The string to determine
3132  * @return bool
3133  * @since 1.25
3134  */
3135 function wfIsInfinity( $str ) {
3136         // These are hardcoded elsewhere in MediaWiki (e.g. mediawiki.special.block.js).
3137         $infinityValues = [ 'infinite', 'indefinite', 'infinity', 'never' ];
3138         return in_array( $str, $infinityValues );
3139 }
3140
3141 /**
3142  * Returns true if these thumbnail parameters match one that MediaWiki
3143  * requests from file description pages and/or parser output.
3144  *
3145  * $params is considered non-standard if they involve a non-standard
3146  * width or any non-default parameters aside from width and page number.
3147  * The number of possible files with standard parameters is far less than
3148  * that of all combinations; rate-limiting for them can thus be more generious.
3149  *
3150  * @param File $file
3151  * @param array $params
3152  * @return bool
3153  * @since 1.24 Moved from thumb.php to GlobalFunctions in 1.25
3154  */
3155 function wfThumbIsStandard( File $file, array $params ) {
3156         global $wgThumbLimits, $wgImageLimits, $wgResponsiveImages;
3157
3158         $multipliers = [ 1 ];
3159         if ( $wgResponsiveImages ) {
3160                 // These available sizes are hardcoded currently elsewhere in MediaWiki.
3161                 // @see Linker::processResponsiveImages
3162                 $multipliers[] = 1.5;
3163                 $multipliers[] = 2;
3164         }
3165
3166         $handler = $file->getHandler();
3167         if ( !$handler || !isset( $params['width'] ) ) {
3168                 return false;
3169         }
3170
3171         $basicParams = [];
3172         if ( isset( $params['page'] ) ) {
3173                 $basicParams['page'] = $params['page'];
3174         }
3175
3176         $thumbLimits = [];
3177         $imageLimits = [];
3178         // Expand limits to account for multipliers
3179         foreach ( $multipliers as $multiplier ) {
3180                 $thumbLimits = array_merge( $thumbLimits, array_map(
3181                         function ( $width ) use ( $multiplier ) {
3182                                 return round( $width * $multiplier );
3183                         }, $wgThumbLimits )
3184                 );
3185                 $imageLimits = array_merge( $imageLimits, array_map(
3186                         function ( $pair ) use ( $multiplier ) {
3187                                 return [
3188                                         round( $pair[0] * $multiplier ),
3189                                         round( $pair[1] * $multiplier ),
3190                                 ];
3191                         }, $wgImageLimits )
3192                 );
3193         }
3194
3195         // Check if the width matches one of $wgThumbLimits
3196         if ( in_array( $params['width'], $thumbLimits ) ) {
3197                 $normalParams = $basicParams + [ 'width' => $params['width'] ];
3198                 // Append any default values to the map (e.g. "lossy", "lossless", ...)
3199                 $handler->normaliseParams( $file, $normalParams );
3200         } else {
3201                 // If not, then check if the width matchs one of $wgImageLimits
3202                 $match = false;
3203                 foreach ( $imageLimits as $pair ) {
3204                         $normalParams = $basicParams + [ 'width' => $pair[0], 'height' => $pair[1] ];
3205                         // Decide whether the thumbnail should be scaled on width or height.
3206                         // Also append any default values to the map (e.g. "lossy", "lossless", ...)
3207                         $handler->normaliseParams( $file, $normalParams );
3208                         // Check if this standard thumbnail size maps to the given width
3209                         if ( $normalParams['width'] == $params['width'] ) {
3210                                 $match = true;
3211                                 break;
3212                         }
3213                 }
3214                 if ( !$match ) {
3215                         return false; // not standard for description pages
3216                 }
3217         }
3218
3219         // Check that the given values for non-page, non-width, params are just defaults
3220         foreach ( $params as $key => $value ) {
3221                 if ( !isset( $normalParams[$key] ) || $normalParams[$key] != $value ) {
3222                         return false;
3223                 }
3224         }
3225
3226         return true;
3227 }
3228
3229 /**
3230  * Merges two (possibly) 2 dimensional arrays into the target array ($baseArray).
3231  *
3232  * Values that exist in both values will be combined with += (all values of the array
3233  * of $newValues will be added to the values of the array of $baseArray, while values,
3234  * that exists in both, the value of $baseArray will be used).
3235  *
3236  * @param array $baseArray The array where you want to add the values of $newValues to
3237  * @param array $newValues An array with new values
3238  * @return array The combined array
3239  * @since 1.26
3240  */
3241 function wfArrayPlus2d( array $baseArray, array $newValues ) {
3242         // First merge items that are in both arrays
3243         foreach ( $baseArray as $name => &$groupVal ) {
3244                 if ( isset( $newValues[$name] ) ) {
3245                         $groupVal += $newValues[$name];
3246                 }
3247         }
3248         // Now add items that didn't exist yet
3249         $baseArray += $newValues;
3250
3251         return $baseArray;
3252 }
3253
3254 /**
3255  * Get system resource usage of current request context.
3256  * Invokes the getrusage(2) system call, requesting RUSAGE_SELF if on PHP5
3257  * or RUSAGE_THREAD if on HHVM. Returns false if getrusage is not available.
3258  *
3259  * @since 1.24
3260  * @return array|bool Resource usage data or false if no data available.
3261  */
3262 function wfGetRusage() {
3263         if ( !function_exists( 'getrusage' ) ) {
3264                 return false;
3265         } elseif ( defined( 'HHVM_VERSION' ) && PHP_OS === 'Linux' ) {
3266                 return getrusage( 2 /* RUSAGE_THREAD */ );
3267         } else {
3268                 return getrusage( 0 /* RUSAGE_SELF */ );
3269         }
3270 }