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         wfDeprecated( __FUNCTION__, '1.32' );
 152         return array_filter( $arr, $callback, ARRAY_FILTER_USE_BOTH );
 153 }
 154
 155 /**
 156  * @deprecated since 1.32, use array_filter() with ARRAY_FILTER_USE_KEY directly
 157  *
 158  * @param array $arr
 159  * @param callable $callback Will be called with the array key and should return a bool which
 160  *   will determine whether the array element is kept.
 161  * @return array
 162  */
 163 function wfArrayFilterByKey( array $arr, callable $callback ) {
 164         wfDeprecated( __FUNCTION__, '1.32' );
 165         return array_filter( $arr, $callback, ARRAY_FILTER_USE_KEY );
 166 }
 167
 168 /**
 169  * Appends to second array if $value differs from that in $default
 170  *
 171  * @param string|int $key
 172  * @param mixed $value
 173  * @param mixed $default
 174  * @param array &$changed Array to alter
 175  * @throws MWException
 176  */
 177 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
 178         if ( is_null( $changed ) ) {
 179                 throw new MWException( 'GlobalFunctions::wfAppendToArrayIfNotDefault got null' );
 180         }
 181         if ( $default[$key] !== $value ) {
 182                 $changed[$key] = $value;
 183         }
 184 }
 185
 186 /**
 187  * Merge arrays in the style of getUserPermissionsErrors, with duplicate removal
 188  * e.g.
 189  *     wfMergeErrorArrays(
 190  *       [ [ 'x' ] ],
 191  *       [ [ 'x', '2' ] ],
 192  *       [ [ 'x' ] ],
 193  *       [ [ 'y' ] ]
 194  *     );
 195  * returns:
 196  *     [
 197  *       [ 'x', '2' ],
 198  *       [ 'x' ],
 199  *       [ 'y' ]
 200  *     ]
 201  *
 202  * @param array ...$args
 203  * @return array
 204  */
 205 function wfMergeErrorArrays( ...$args ) {
 206         $out = [];
 207         foreach ( $args as $errors ) {
 208                 foreach ( $errors as $params ) {
 209                         $originalParams = $params;
 210                         if ( $params[0] instanceof MessageSpecifier ) {
 211                                 $msg = $params[0];
 212                                 $params = array_merge( [ $msg->getKey() ], $msg->getParams() );
 213                         }
 214                         # @todo FIXME: Sometimes get nested arrays for $params,
 215                         # which leads to E_NOTICEs
 216                         $spec = implode( "\t", $params );
 217                         $out[$spec] = $originalParams;
 218                 }
 219         }
 220         return array_values( $out );
 221 }
 222
 223 /**
 224  * Insert array into another array after the specified *KEY*
 225  *
 226  * @param array $array The array.
 227  * @param array $insert The array to insert.
 228  * @param mixed $after The key to insert after
 229  * @return array
 230  */
 231 function wfArrayInsertAfter( array $array, array $insert, $after ) {
 232         // Find the offset of the element to insert after.
 233         $keys = array_keys( $array );
 234         $offsetByKey = array_flip( $keys );
 235
 236         $offset = $offsetByKey[$after];
 237
 238         // Insert at the specified offset
 239         $before = array_slice( $array, 0, $offset + 1, true );
 240         $after = array_slice( $array, $offset + 1, count( $array ) - $offset, true );
 241
 242         $output = $before + $insert + $after;
 243
 244         return $output;
 245 }
 246
 247 /**
 248  * Recursively converts the parameter (an object) to an array with the same data
 249  *
 250  * @param object|array $objOrArray
 251  * @param bool $recursive
 252  * @return array
 253  */
 254 function wfObjectToArray( $objOrArray, $recursive = true ) {
 255         $array = [];
 256         if ( is_object( $objOrArray ) ) {
 257                 $objOrArray = get_object_vars( $objOrArray );
 258         }
 259         foreach ( $objOrArray as $key => $value ) {
 260                 if ( $recursive && ( is_object( $value ) || is_array( $value ) ) ) {
 261                         $value = wfObjectToArray( $value );
 262                 }
 263
 264                 $array[$key] = $value;
 265         }
 266
 267         return $array;
 268 }
 269
 270 /**
 271  * Get a random decimal value in the domain of [0, 1), in a way
 272  * not likely to give duplicate values for any realistic
 273  * number of articles.
 274  *
 275  * @note This is designed for use in relation to Special:RandomPage
 276  *       and the page_random database field.
 277  *
 278  * @return string
 279  */
 280 function wfRandom() {
 281         // The maximum random value is "only" 2^31-1, so get two random
 282         // values to reduce the chance of dupes
 283         $max = mt_getrandmax() + 1;
 284         $rand = number_format( ( mt_rand() * $max + mt_rand() ) / $max / $max, 12, '.', '' );
 285         return $rand;
 286 }
 287
 288 /**
 289  * Get a random string containing a number of pseudo-random hex characters.
 290  *
 291  * @note This is not secure, if you are trying to generate some sort
 292  *       of token please use MWCryptRand instead.
 293  *
 294  * @param int $length The length of the string to generate
 295  * @return string
 296  * @since 1.20
 297  */
 298 function wfRandomString( $length = 32 ) {
 299         $str = '';
 300         for ( $n = 0; $n < $length; $n += 7 ) {
 301                 $str .= sprintf( '%07x', mt_rand() & 0xfffffff );
 302         }
 303         return substr( $str, 0, $length );
 304 }
 305
 306 /**
 307  * We want some things to be included as literal characters in our title URLs
 308  * for prettiness, which urlencode encodes by default.  According to RFC 1738,
 309  * all of the following should be safe:
 310  *
 311  * ;:@&=$-_.+!*'(),
 312  *
 313  * RFC 1738 says ~ is unsafe, however RFC 3986 considers it an unreserved
 314  * character which should not be encoded. More importantly, google chrome
 315  * always converts %7E back to ~, and converting it in this function can
 316  * cause a redirect loop (T105265).
 317  *
 318  * But + is not safe because it's used to indicate a space; &= are only safe in
 319  * paths and not in queries (and we don't distinguish here); ' seems kind of
 320  * scary; and urlencode() doesn't touch -_. to begin with.  Plus, although /
 321  * is reserved, we don't care.  So the list we unescape is:
 322  *
 323  * ;:@$!*(),/~
 324  *
 325  * However, IIS7 redirects fail when the url contains a colon (see T24709),
 326  * so no fancy : for IIS7.
 327  *
 328  * %2F in the page titles seems to fatally break for some reason.
 329  *
 330  * @param string $s
 331  * @return string
 332  */
 333 function wfUrlencode( $s ) {
 334         static $needle;
 335
 336         if ( is_null( $s ) ) {
 337                 $needle = null;
 338                 return '';
 339         }
 340
 341         if ( is_null( $needle ) ) {
 342                 $needle = [ '%3B', '%40', '%24', '%21', '%2A', '%28', '%29', '%2C', '%2F', '%7E' ];
 343                 if ( !isset( $_SERVER['SERVER_SOFTWARE'] ) ||
 344                         ( strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/7' ) === false )
 345                 ) {
 346                         $needle[] = '%3A';
 347                 }
 348         }
 349
 350         $s = urlencode( $s );
 351         $s = str_ireplace(
 352                 $needle,
 353                 [ ';', '@', '$', '!', '*', '(', ')', ',', '/', '~', ':' ],
 354                 $s
 355         );
 356
 357         return $s;
 358 }
 359
 360 /**
 361  * This function takes one or two arrays as input, and returns a CGI-style string, e.g.
 362  * "days=7&limit=100". Options in the first array override options in the second.
 363  * Options set to null or false will not be output.
 364  *
 365  * @param array $array1 ( String|Array )
 366  * @param array|null $array2 ( String|Array )
 367  * @param string $prefix
 368  * @return string
 369  */
 370 function wfArrayToCgi( $array1, $array2 = null, $prefix = '' ) {
 371         if ( !is_null( $array2 ) ) {
 372                 $array1 = $array1 + $array2;
 373         }
 374
 375         $cgi = '';
 376         foreach ( $array1 as $key => $value ) {
 377                 if ( !is_null( $value ) && $value !== false ) {
 378                         if ( $cgi != '' ) {
 379                                 $cgi .= '&';
 380                         }
 381                         if ( $prefix !== '' ) {
 382                                 $key = $prefix . "[$key]";
 383                         }
 384                         if ( is_array( $value ) ) {
 385                                 $firstTime = true;
 386                                 foreach ( $value as $k => $v ) {
 387                                         $cgi .= $firstTime ? '' : '&';
 388                                         if ( is_array( $v ) ) {
 389                                                 $cgi .= wfArrayToCgi( $v, null, $key . "[$k]" );
 390                                         } else {
 391                                                 $cgi .= urlencode( $key . "[$k]" ) . '=' . urlencode( $v );
 392                                         }
 393                                         $firstTime = false;
 394                                 }
 395                         } else {
 396                                 if ( is_object( $value ) ) {
 397                                         $value = $value->__toString();
 398                                 }
 399                                 $cgi .= urlencode( $key ) . '=' . urlencode( $value );
 400                         }
 401                 }
 402         }
 403         return $cgi;
 404 }
 405
 406 /**
 407  * This is the logical opposite of wfArrayToCgi(): it accepts a query string as
 408  * its argument and returns the same string in array form.  This allows compatibility
 409  * with legacy functions that accept raw query strings instead of nice
 410  * arrays.  Of course, keys and values are urldecode()d.
 411  *
 412  * @param string $query Query string
 413  * @return string[] Array version of input
 414  */
 415 function wfCgiToArray( $query ) {
 416         if ( isset( $query[0] ) && $query[0] == '?' ) {
 417                 $query = substr( $query, 1 );
 418         }
 419         $bits = explode( '&', $query );
 420         $ret = [];
 421         foreach ( $bits as $bit ) {
 422                 if ( $bit === '' ) {
 423                         continue;
 424                 }
 425                 if ( strpos( $bit, '=' ) === false ) {
 426                         // Pieces like &qwerty become 'qwerty' => '' (at least this is what php does)
 427                         $key = $bit;
 428                         $value = '';
 429                 } else {
 430                         list( $key, $value ) = explode( '=', $bit );
 431                 }
 432                 $key = urldecode( $key );
 433                 $value = urldecode( $value );
 434                 if ( strpos( $key, '[' ) !== false ) {
 435                         $keys = array_reverse( explode( '[', $key ) );
 436                         $key = array_pop( $keys );
 437                         $temp = $value;
 438                         foreach ( $keys as $k ) {
 439                                 $k = substr( $k, 0, -1 );
 440                                 $temp = [ $k => $temp ];
 441                         }
 442                         if ( isset( $ret[$key] ) ) {
 443                                 $ret[$key] = array_merge( $ret[$key], $temp );
 444                         } else {
 445                                 $ret[$key] = $temp;
 446                         }
 447                 } else {
 448                         $ret[$key] = $value;
 449                 }
 450         }
 451         return $ret;
 452 }
 453
 454 /**
 455  * Append a query string to an existing URL, which may or may not already
 456  * have query string parameters already. If so, they will be combined.
 457  *
 458  * @param string $url
 459  * @param string|string[] $query String or associative array
 460  * @return string
 461  */
 462 function wfAppendQuery( $url, $query ) {
 463         if ( is_array( $query ) ) {
 464                 $query = wfArrayToCgi( $query );
 465         }
 466         if ( $query != '' ) {
 467                 // Remove the fragment, if there is one
 468                 $fragment = false;
 469                 $hashPos = strpos( $url, '#' );
 470                 if ( $hashPos !== false ) {
 471                         $fragment = substr( $url, $hashPos );
 472                         $url = substr( $url, 0, $hashPos );
 473                 }
 474
 475                 // Add parameter
 476                 if ( strpos( $url, '?' ) === false ) {
 477                         $url .= '?';
 478                 } else {
 479                         $url .= '&';
 480                 }
 481                 $url .= $query;
 482
 483                 // Put the fragment back
 484                 if ( $fragment !== false ) {
 485                         $url .= $fragment;
 486                 }
 487         }
 488         return $url;
 489 }
 490
 491 /**
 492  * Expand a potentially local URL to a fully-qualified URL. Assumes $wgServer
 493  * is correct.
 494  *
 495  * The meaning of the PROTO_* constants is as follows:
 496  * PROTO_HTTP: Output a URL starting with http://
 497  * PROTO_HTTPS: Output a URL starting with https://
 498  * PROTO_RELATIVE: Output a URL starting with // (protocol-relative URL)
 499  * PROTO_CURRENT: Output a URL starting with either http:// or https:// , depending
 500  *    on which protocol was used for the current incoming request
 501  * PROTO_CANONICAL: For URLs without a domain, like /w/index.php , use $wgCanonicalServer.
 502  *    For protocol-relative URLs, use the protocol of $wgCanonicalServer
 503  * PROTO_INTERNAL: Like PROTO_CANONICAL, but uses $wgInternalServer instead of $wgCanonicalServer
 504  *
 505  * @todo this won't work with current-path-relative URLs
 506  * like "subdir/foo.html", etc.
 507  *
 508  * @param string $url Either fully-qualified or a local path + query
 509  * @param string|int|null $defaultProto One of the PROTO_* constants. Determines the
 510  *    protocol to use if $url or $wgServer is protocol-relative
 511  * @return string|false Fully-qualified URL, current-path-relative URL or false if
 512  *    no valid URL can be constructed
 513  */
 514 function wfExpandUrl( $url, $defaultProto = PROTO_CURRENT ) {
 515         global $wgServer, $wgCanonicalServer, $wgInternalServer, $wgRequest,
 516                 $wgHttpsPort;
 517         if ( $defaultProto === PROTO_CANONICAL ) {
 518                 $serverUrl = $wgCanonicalServer;
 519         } elseif ( $defaultProto === PROTO_INTERNAL && $wgInternalServer !== false ) {
 520                 // Make $wgInternalServer fall back to $wgServer if not set
 521                 $serverUrl = $wgInternalServer;
 522         } else {
 523                 $serverUrl = $wgServer;
 524                 if ( $defaultProto === PROTO_CURRENT ) {
 525                         $defaultProto = $wgRequest->getProtocol() . '://';
 526                 }
 527         }
 528
 529         // Analyze $serverUrl to obtain its protocol
 530         $bits = wfParseUrl( $serverUrl );
 531         $serverHasProto = $bits && $bits['scheme'] != '';
 532
 533         if ( $defaultProto === PROTO_CANONICAL || $defaultProto === PROTO_INTERNAL ) {
 534                 if ( $serverHasProto ) {
 535                         $defaultProto = $bits['scheme'] . '://';
 536                 } else {
 537                         // $wgCanonicalServer or $wgInternalServer doesn't have a protocol.
 538                         // This really isn't supposed to happen. Fall back to HTTP in this
 539                         // ridiculous case.
 540                         $defaultProto = PROTO_HTTP;
 541                 }
 542         }
 543
 544         $defaultProtoWithoutSlashes = substr( $defaultProto, 0, -2 );
 545
 546         if ( substr( $url, 0, 2 ) == '//' ) {
 547                 $url = $defaultProtoWithoutSlashes . $url;
 548         } elseif ( substr( $url, 0, 1 ) == '/' ) {
 549                 // If $serverUrl is protocol-relative, prepend $defaultProtoWithoutSlashes,
 550                 // otherwise leave it alone.
 551                 if ( $serverHasProto ) {
 552                         $url = $serverUrl . $url;
 553                 } else {
 554                         // If an HTTPS URL is synthesized from a protocol-relative $wgServer, allow the
 555                         // user to override the port number (T67184)
 556                         if ( $defaultProto === PROTO_HTTPS && $wgHttpsPort != 443 ) {
 557                                 if ( isset( $bits['port'] ) ) {
 558                                         throw new Exception( 'A protocol-relative $wgServer may not contain a port number' );
 559                                 }
 560                                 $url = $defaultProtoWithoutSlashes . $serverUrl . ':' . $wgHttpsPort . $url;
 561                         } else {
 562                                 $url = $defaultProtoWithoutSlashes . $serverUrl . $url;
 563                         }
 564                 }
 565         }
 566
 567         $bits = wfParseUrl( $url );
 568
 569         if ( $bits && isset( $bits['path'] ) ) {
 570                 $bits['path'] = wfRemoveDotSegments( $bits['path'] );
 571                 return wfAssembleUrl( $bits );
 572         } elseif ( $bits ) {
 573                 # No path to expand
 574                 return $url;
 575         } elseif ( substr( $url, 0, 1 ) != '/' ) {
 576                 # URL is a relative path
 577                 return wfRemoveDotSegments( $url );
 578         }
 579
 580         # Expanded URL is not valid.
 581         return false;
 582 }
 583
 584 /**
 585  * Get the wiki's "server", i.e. the protocol and host part of the URL, with a
 586  * protocol specified using a PROTO_* constant as in wfExpandUrl()
 587  *
 588  * @since 1.32
 589  * @param string|int|null $proto One of the PROTO_* constants.
 590  * @return string The URL
 591  */
 592 function wfGetServerUrl( $proto ) {
 593         $url = wfExpandUrl( '/', $proto );
 594         return substr( $url, 0, -1 );
 595 }
 596
 597 /**
 598  * This function will reassemble a URL parsed with wfParseURL.  This is useful
 599  * if you need to edit part of a URL and put it back together.
 600  *
 601  * This is the basic structure used (brackets contain keys for $urlParts):
 602  * [scheme][delimiter][user]:[pass]@[host]:[port][path]?[query]#[fragment]
 603  *
 604  * @todo Need to integrate this into wfExpandUrl (see T34168)
 605  *
 606  * @since 1.19
 607  * @param array $urlParts URL parts, as output from wfParseUrl
 608  * @return string URL assembled from its component parts
 609  */
 610 function wfAssembleUrl( $urlParts ) {
 611         $result = '';
 612
 613         if ( isset( $urlParts['delimiter'] ) ) {
 614                 if ( isset( $urlParts['scheme'] ) ) {
 615                         $result .= $urlParts['scheme'];
 616                 }
 617
 618                 $result .= $urlParts['delimiter'];
 619         }
 620
 621         if ( isset( $urlParts['host'] ) ) {
 622                 if ( isset( $urlParts['user'] ) ) {
 623                         $result .= $urlParts['user'];
 624                         if ( isset( $urlParts['pass'] ) ) {
 625                                 $result .= ':' . $urlParts['pass'];
 626                         }
 627                         $result .= '@';
 628                 }
 629
 630                 $result .= $urlParts['host'];
 631
 632                 if ( isset( $urlParts['port'] ) ) {
 633                         $result .= ':' . $urlParts['port'];
 634                 }
 635         }
 636
 637         if ( isset( $urlParts['path'] ) ) {
 638                 $result .= $urlParts['path'];
 639         }
 640
 641         if ( isset( $urlParts['query'] ) ) {
 642                 $result .= '?' . $urlParts['query'];
 643         }
 644
 645         if ( isset( $urlParts['fragment'] ) ) {
 646                 $result .= '#' . $urlParts['fragment'];
 647         }
 648
 649         return $result;
 650 }
 651
 652 /**
 653  * Remove all dot-segments in the provided URL path.  For example,
 654  * '/a/./b/../c/' becomes '/a/c/'.  For details on the algorithm, please see
 655  * RFC3986 section 5.2.4.
 656  *
 657  * @todo Need to integrate this into wfExpandUrl (see T34168)
 658  *
 659  * @since 1.19
 660  *
 661  * @param string $urlPath URL path, potentially containing dot-segments
 662  * @return string URL path with all dot-segments removed
 663  */
 664 function wfRemoveDotSegments( $urlPath ) {
 665         $output = '';
 666         $inputOffset = 0;
 667         $inputLength = strlen( $urlPath );
 668
 669         while ( $inputOffset < $inputLength ) {
 670                 $prefixLengthOne = substr( $urlPath, $inputOffset, 1 );
 671                 $prefixLengthTwo = substr( $urlPath, $inputOffset, 2 );
 672                 $prefixLengthThree = substr( $urlPath, $inputOffset, 3 );
 673                 $prefixLengthFour = substr( $urlPath, $inputOffset, 4 );
 674                 $trimOutput = false;
 675
 676                 if ( $prefixLengthTwo == './' ) {
 677                         # Step A, remove leading "./"
 678                         $inputOffset += 2;
 679                 } elseif ( $prefixLengthThree == '../' ) {
 680                         # Step A, remove leading "../"
 681                         $inputOffset += 3;
 682                 } elseif ( ( $prefixLengthTwo == '/.' ) && ( $inputOffset + 2 == $inputLength ) ) {
 683                         # Step B, replace leading "/.$" with "/"
 684                         $inputOffset += 1;
 685                         $urlPath[$inputOffset] = '/';
 686                 } elseif ( $prefixLengthThree == '/./' ) {
 687                         # Step B, replace leading "/./" with "/"
 688                         $inputOffset += 2;
 689                 } elseif ( $prefixLengthThree == '/..' && ( $inputOffset + 3 == $inputLength ) ) {
 690                         # Step C, replace leading "/..$" with "/" and
 691                         # remove last path component in output
 692                         $inputOffset += 2;
 693                         $urlPath[$inputOffset] = '/';
 694                         $trimOutput = true;
 695                 } elseif ( $prefixLengthFour == '/../' ) {
 696                         # Step C, replace leading "/../" with "/" and
 697                         # remove last path component in output
 698                         $inputOffset += 3;
 699                         $trimOutput = true;
 700                 } elseif ( ( $prefixLengthOne == '.' ) && ( $inputOffset + 1 == $inputLength ) ) {
 701                         # Step D, remove "^.$"
 702                         $inputOffset += 1;
 703                 } elseif ( ( $prefixLengthTwo == '..' ) && ( $inputOffset + 2 == $inputLength ) ) {
 704                         # Step D, remove "^..$"
 705                         $inputOffset += 2;
 706                 } else {
 707                         # Step E, move leading path segment to output
 708                         if ( $prefixLengthOne == '/' ) {
 709                                 $slashPos = strpos( $urlPath, '/', $inputOffset + 1 );
 710                         } else {
 711                                 $slashPos = strpos( $urlPath, '/', $inputOffset );
 712                         }
 713                         if ( $slashPos === false ) {
 714                                 $output .= substr( $urlPath, $inputOffset );
 715                                 $inputOffset = $inputLength;
 716                         } else {
 717                                 $output .= substr( $urlPath, $inputOffset, $slashPos - $inputOffset );
 718                                 $inputOffset += $slashPos - $inputOffset;
 719                         }
 720                 }
 721
 722                 if ( $trimOutput ) {
 723                         $slashPos = strrpos( $output, '/' );
 724                         if ( $slashPos === false ) {
 725                                 $output = '';
 726                         } else {
 727                                 $output = substr( $output, 0, $slashPos );
 728                         }
 729                 }
 730         }
 731
 732         return $output;
 733 }
 734
 735 /**
 736  * Returns a regular expression of url protocols
 737  *
 738  * @param bool $includeProtocolRelative If false, remove '//' from the returned protocol list.
 739  *        DO NOT USE this directly, use wfUrlProtocolsWithoutProtRel() instead
 740  * @return string
 741  */
 742 function wfUrlProtocols( $includeProtocolRelative = true ) {
 743         global $wgUrlProtocols;
 744
 745         // Cache return values separately based on $includeProtocolRelative
 746         static $withProtRel = null, $withoutProtRel = null;
 747         $cachedValue = $includeProtocolRelative ? $withProtRel : $withoutProtRel;
 748         if ( !is_null( $cachedValue ) ) {
 749                 return $cachedValue;
 750         }
 751
 752         // Support old-style $wgUrlProtocols strings, for backwards compatibility
 753         // with LocalSettings files from 1.5
 754         if ( is_array( $wgUrlProtocols ) ) {
 755                 $protocols = [];
 756                 foreach ( $wgUrlProtocols as $protocol ) {
 757                         // Filter out '//' if !$includeProtocolRelative
 758                         if ( $includeProtocolRelative || $protocol !== '//' ) {
 759                                 $protocols[] = preg_quote( $protocol, '/' );
 760                         }
 761                 }
 762
 763                 $retval = implode( '|', $protocols );
 764         } else {
 765                 // Ignore $includeProtocolRelative in this case
 766                 // This case exists for pre-1.6 compatibility, and we can safely assume
 767                 // that '//' won't appear in a pre-1.6 config because protocol-relative
 768                 // URLs weren't supported until 1.18
 769                 $retval = $wgUrlProtocols;
 770         }
 771
 772         // Cache return value
 773         if ( $includeProtocolRelative ) {
 774                 $withProtRel = $retval;
 775         } else {
 776                 $withoutProtRel = $retval;
 777         }
 778         return $retval;
 779 }
 780
 781 /**
 782  * Like wfUrlProtocols(), but excludes '//' from the protocol list. Use this if
 783  * you need a regex that matches all URL protocols but does not match protocol-
 784  * relative URLs
 785  * @return string
 786  */
 787 function wfUrlProtocolsWithoutProtRel() {
 788         return wfUrlProtocols( false );
 789 }
 790
 791 /**
 792  * parse_url() work-alike, but non-broken.  Differences:
 793  *
 794  * 1) Does not raise warnings on bad URLs (just returns false).
 795  * 2) Handles protocols that don't use :// (e.g., mailto: and news:, as well as
 796  *    protocol-relative URLs) correctly.
 797  * 3) Adds a "delimiter" element to the array (see (2)).
 798  * 4) Verifies that the protocol is on the $wgUrlProtocols whitelist.
 799  * 5) Rejects some invalid URLs that parse_url doesn't, e.g. the empty string or URLs starting with
 800  *    a line feed character.
 801  *
 802  * @param string $url A URL to parse
 803  * @return string[]|bool Bits of the URL in an associative array, or false on failure.
 804  *   Possible fields:
 805  *   - scheme: URI scheme (protocol), e.g. 'http', 'mailto'. Lowercase, always present, but can
 806  *       be an empty string for protocol-relative URLs.
 807  *   - delimiter: either '://', ':' or '//'. Always present.
 808  *   - host: domain name / IP. Always present, but could be an empty string, e.g. for file: URLs.
 809  *   - user: user name, e.g. for HTTP Basic auth URLs such as http://user:pass@example.com/
 810  *       Missing when there is no username.
 811  *   - pass: password, same as above.
 812  *   - path: path including the leading /. Will be missing when empty (e.g. 'http://example.com')
 813  *   - query: query string (as a string; see wfCgiToArray() for parsing it), can be missing.
 814  *   - fragment: the part after #, can be missing.
 815  */
 816 function wfParseUrl( $url ) {
 817         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
 818
 819         // Protocol-relative URLs are handled really badly by parse_url(). It's so
 820         // bad that the easiest way to handle them is to just prepend 'http:' and
 821         // strip the protocol out later.
 822         $wasRelative = substr( $url, 0, 2 ) == '//';
 823         if ( $wasRelative ) {
 824                 $url = "http:$url";
 825         }
 826         Wikimedia\suppressWarnings();
 827         $bits = parse_url( $url );
 828         Wikimedia\restoreWarnings();
 829         // parse_url() returns an array without scheme for some invalid URLs, e.g.
 830         // parse_url("%0Ahttp://example.com") == [ 'host' => '%0Ahttp', 'path' => 'example.com' ]
 831         if ( !$bits || !isset( $bits['scheme'] ) ) {
 832                 return false;
 833         }
 834
 835         // parse_url() incorrectly handles schemes case-sensitively. Convert it to lowercase.
 836         $bits['scheme'] = strtolower( $bits['scheme'] );
 837
 838         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
 839         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
 840                 $bits['delimiter'] = '://';
 841         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
 842                 $bits['delimiter'] = ':';
 843                 // parse_url detects for news: and mailto: the host part of an url as path
 844                 // We have to correct this wrong detection
 845                 if ( isset( $bits['path'] ) ) {
 846                         $bits['host'] = $bits['path'];
 847                         $bits['path'] = '';
 848                 }
 849         } else {
 850                 return false;
 851         }
 852
 853         /* Provide an empty host for eg. file:/// urls (see T30627) */
 854         if ( !isset( $bits['host'] ) ) {
 855                 $bits['host'] = '';
 856
 857                 // See T47069
 858                 if ( isset( $bits['path'] ) ) {
 859                         /* parse_url loses the third / for file:///c:/ urls (but not on variants) */
 860                         if ( substr( $bits['path'], 0, 1 ) !== '/' ) {
 861                                 $bits['path'] = '/' . $bits['path'];
 862                         }
 863                 } else {
 864                         $bits['path'] = '';
 865                 }
 866         }
 867
 868         // If the URL was protocol-relative, fix scheme and delimiter
 869         if ( $wasRelative ) {
 870                 $bits['scheme'] = '';
 871                 $bits['delimiter'] = '//';
 872         }
 873         return $bits;
 874 }
 875
 876 /**
 877  * Take a URL, make sure it's expanded to fully qualified, and replace any
 878  * encoded non-ASCII Unicode characters with their UTF-8 original forms
 879  * for more compact display and legibility for local audiences.
 880  *
 881  * @todo handle punycode domains too
 882  *
 883  * @param string $url
 884  * @return string
 885  */
 886 function wfExpandIRI( $url ) {
 887         return preg_replace_callback(
 888                 '/((?:%[89A-F][0-9A-F])+)/i',
 889                 function ( array $matches ) {
 890                         return urldecode( $matches[1] );
 891                 },
 892                 wfExpandUrl( $url )
 893         );
 894 }
 895
 896 /**
 897  * Make URL indexes, appropriate for the el_index field of externallinks.
 898  *
 899  * @deprecated since 1.33, use LinkFilter::makeIndexes() instead
 900  * @param string $url
 901  * @return array
 902  */
 903 function wfMakeUrlIndexes( $url ) {
 904         wfDeprecated( __FUNCTION__, '1.33' );
 905         return LinkFilter::makeIndexes( $url );
 906 }
 907
 908 /**
 909  * Check whether a given URL has a domain that occurs in a given set of domains
 910  * @param string $url
 911  * @param array $domains Array of domains (strings)
 912  * @return bool True if the host part of $url ends in one of the strings in $domains
 913  */
 914 function wfMatchesDomainList( $url, $domains ) {
 915         $bits = wfParseUrl( $url );
 916         if ( is_array( $bits ) && isset( $bits['host'] ) ) {
 917                 $host = '.' . $bits['host'];
 918                 foreach ( (array)$domains as $domain ) {
 919                         $domain = '.' . $domain;
 920                         if ( substr( $host, -strlen( $domain ) ) === $domain ) {
 921                                 return true;
 922                         }
 923                 }
 924         }
 925         return false;
 926 }
 927
 928 /**
 929  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
 930  * In normal operation this is a NOP.
 931  *
 932  * Controlling globals:
 933  * $wgDebugLogFile - points to the log file
 934  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
 935  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
 936  *
 937  * @since 1.25 support for additional context data
 938  *
 939  * @param string $text
 940  * @param string|bool $dest Destination of the message:
 941  *     - 'all': both to the log and HTML (debug toolbar or HTML comments)
 942  *     - 'private': excluded from HTML output
 943  *   For backward compatibility, it can also take a boolean:
 944  *     - true: same as 'all'
 945  *     - false: same as 'private'
 946  * @param array $context Additional logging context data
 947  */
 948 function wfDebug( $text, $dest = 'all', array $context = [] ) {
 949         global $wgDebugRawPage, $wgDebugLogPrefix;
 950         global $wgDebugTimestamps;
 951
 952         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
 953                 return;
 954         }
 955
 956         $text = trim( $text );
 957
 958         if ( $wgDebugTimestamps ) {
 959                 $context['seconds_elapsed'] = sprintf(
 960                         '%6.4f',
 961                         microtime( true ) - $_SERVER['REQUEST_TIME_FLOAT']
 962                 );
 963                 $context['memory_used'] = sprintf(
 964                         '%5.1fM',
 965                         ( memory_get_usage( true ) / ( 1024 * 1024 ) )
 966                 );
 967         }
 968
 969         if ( $wgDebugLogPrefix !== '' ) {
 970                 $context['prefix'] = $wgDebugLogPrefix;
 971         }
 972         $context['private'] = ( $dest === false || $dest === 'private' );
 973
 974         $logger = LoggerFactory::getInstance( 'wfDebug' );
 975         $logger->debug( $text, $context );
 976 }
 977
 978 /**
 979  * Returns true if debug logging should be suppressed if $wgDebugRawPage = false
 980  * @return bool
 981  */
 982 function wfIsDebugRawPage() {
 983         static $cache;
 984         if ( $cache !== null ) {
 985                 return $cache;
 986         }
 987         // Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
 988         // phpcs:ignore MediaWiki.Usage.SuperGlobalsUsage.SuperGlobals
 989         if ( ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' )
 990                 || (
 991                         isset( $_SERVER['SCRIPT_NAME'] )
 992                         && substr( $_SERVER['SCRIPT_NAME'], -8 ) == 'load.php'
 993                 )
 994         ) {
 995                 $cache = true;
 996         } else {
 997                 $cache = false;
 998         }
 999         return $cache;
1000 }
1001
1002 /**
1003  * Send a line giving PHP memory usage.
1004  *
1005  * @param bool $exact Print exact byte values instead of kibibytes (default: false)
1006  */
1007 function wfDebugMem( $exact = false ) {
1008         $mem = memory_get_usage();
1009         if ( !$exact ) {
1010                 $mem = floor( $mem / 1024 ) . ' KiB';
1011         } else {
1012                 $mem .= ' B';
1013         }
1014         wfDebug( "Memory usage: $mem\n" );
1015 }
1016
1017 /**
1018  * Send a line to a supplementary debug log file, if configured, or main debug
1019  * log if not.
1020  *
1021  * To configure a supplementary log file, set $wgDebugLogGroups[$logGroup] to
1022  * a string filename or an associative array mapping 'destination' to the
1023  * desired filename. The associative array may also contain a 'sample' key
1024  * with an integer value, specifying a sampling factor. Sampled log events
1025  * will be emitted with a 1 in N random chance.
1026  *
1027  * @since 1.23 support for sampling log messages via $wgDebugLogGroups.
1028  * @since 1.25 support for additional context data
1029  * @since 1.25 sample behavior dependent on configured $wgMWLoggerDefaultSpi
1030  *
1031  * @param string $logGroup
1032  * @param string $text
1033  * @param string|bool $dest Destination of the message:
1034  *     - 'all': both to the log and HTML (debug toolbar or HTML comments)
1035  *     - 'private': only to the specific log if set in $wgDebugLogGroups and
1036  *       discarded otherwise
1037  *   For backward compatibility, it can also take a boolean:
1038  *     - true: same as 'all'
1039  *     - false: same as 'private'
1040  * @param array $context Additional logging context data
1041  */
1042 function wfDebugLog(
1043         $logGroup, $text, $dest = 'all', array $context = []
1044 ) {
1045         $text = trim( $text );
1046
1047         $logger = LoggerFactory::getInstance( $logGroup );
1048         $context['private'] = ( $dest === false || $dest === 'private' );
1049         $logger->info( $text, $context );
1050 }
1051
1052 /**
1053  * Log for database errors
1054  *
1055  * @since 1.25 support for additional context data
1056  *
1057  * @param string $text Database error message.
1058  * @param array $context Additional logging context data
1059  */
1060 function wfLogDBError( $text, array $context = [] ) {
1061         $logger = LoggerFactory::getInstance( 'wfLogDBError' );
1062         $logger->error( trim( $text ), $context );
1063 }
1064
1065 /**
1066  * Throws a warning that $function is deprecated
1067  *
1068  * @param string $function Function that is deprecated.
1069  * @param string|bool $version Version of MediaWiki that the function
1070  *    was deprecated in (Added in 1.19).
1071  * @param string|bool $component Component to which the function belongs.
1072  *    If false, it is assumed the function is in MediaWiki core (Added in 1.19).
1073  * @param int $callerOffset How far up the call stack is the original
1074  *    caller. 2 = function that called the function that called
1075  *    wfDeprecated (Added in 1.20).
1076  */
1077 function wfDeprecated( $function, $version = false, $component = false, $callerOffset = 2 ) {
1078         MWDebug::deprecated( $function, $version, $component, $callerOffset + 1 );
1079 }
1080
1081 /**
1082  * Send a warning either to the debug log or in a PHP error depending on
1083  * $wgDevelopmentWarnings. To log warnings in production, use wfLogWarning() instead.
1084  *
1085  * @param string $msg Message to send
1086  * @param int $callerOffset Number of items to go back in the backtrace to
1087  *        find the correct caller (1 = function calling wfWarn, ...)
1088  * @param int $level PHP error level; defaults to E_USER_NOTICE;
1089  *        only used when $wgDevelopmentWarnings is true
1090  */
1091 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
1092         MWDebug::warning( $msg, $callerOffset + 1, $level, 'auto' );
1093 }
1094
1095 /**
1096  * Send a warning as a PHP error and the debug log. This is intended for logging
1097  * warnings in production. For logging development warnings, use WfWarn instead.
1098  *
1099  * @param string $msg Message to send
1100  * @param int $callerOffset Number of items to go back in the backtrace to
1101  *        find the correct caller (1 = function calling wfLogWarning, ...)
1102  * @param int $level PHP error level; defaults to E_USER_WARNING
1103  */
1104 function wfLogWarning( $msg, $callerOffset = 1, $level = E_USER_WARNING ) {
1105         MWDebug::warning( $msg, $callerOffset + 1, $level, 'production' );
1106 }
1107
1108 /**
1109  * @todo document
1110  * @todo Move logic to MediaWiki.php
1111  */
1112 function wfLogProfilingData() {
1113         global $wgDebugLogGroups, $wgDebugRawPage;
1114
1115         $context = RequestContext::getMain();
1116         $request = $context->getRequest();
1117
1118         $profiler = Profiler::instance();
1119         $profiler->setContext( $context );
1120         $profiler->logData();
1121
1122         // Send out any buffered statsd metrics as needed
1123         MediaWiki::emitBufferedStatsdData(
1124                 MediaWikiServices::getInstance()->getStatsdDataFactory(),
1125                 $context->getConfig()
1126         );
1127
1128         // Profiling must actually be enabled...
1129         if ( $profiler instanceof ProfilerStub ) {
1130                 return;
1131         }
1132
1133         if ( isset( $wgDebugLogGroups['profileoutput'] )
1134                 && $wgDebugLogGroups['profileoutput'] === false
1135         ) {
1136                 // Explicitly disabled
1137                 return;
1138         }
1139         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
1140                 return;
1141         }
1142
1143         $ctx = [ 'elapsed' => $request->getElapsedTime() ];
1144         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
1145                 $ctx['forwarded_for'] = $_SERVER['HTTP_X_FORWARDED_FOR'];
1146         }
1147         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
1148                 $ctx['client_ip'] = $_SERVER['HTTP_CLIENT_IP'];
1149         }
1150         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
1151                 $ctx['from'] = $_SERVER['HTTP_FROM'];
1152         }
1153         if ( isset( $ctx['forwarded_for'] ) ||
1154                 isset( $ctx['client_ip'] ) ||
1155                 isset( $ctx['from'] ) ) {
1156                 $ctx['proxy'] = $_SERVER['REMOTE_ADDR'];
1157         }
1158
1159         // Don't load $wgUser at this late stage just for statistics purposes
1160         // @todo FIXME: We can detect some anons even if it is not loaded.
1161         // See User::getId()
1162         $user = $context->getUser();
1163         $ctx['anon'] = $user->isItemLoaded( 'id' ) && $user->isAnon();
1164
1165         // Command line script uses a FauxRequest object which does not have
1166         // any knowledge about an URL and throw an exception instead.
1167         try {
1168                 $ctx['url'] = urldecode( $request->getRequestURL() );
1169         } catch ( Exception $ignored ) {
1170                 // no-op
1171         }
1172
1173         $ctx['output'] = $profiler->getOutput();
1174
1175         $log = LoggerFactory::getInstance( 'profileoutput' );
1176         $log->info( "Elapsed: {elapsed}; URL: <{url}>\n{output}", $ctx );
1177 }
1178
1179 /**
1180  * Increment a statistics counter
1181  *
1182  * @param string $key
1183  * @param int $count
1184  * @return void
1185  */
1186 function wfIncrStats( $key, $count = 1 ) {
1187         $stats = MediaWikiServices::getInstance()->getStatsdDataFactory();
1188         $stats->updateCount( $key, $count );
1189 }
1190
1191 /**
1192  * Check whether the wiki is in read-only mode.
1193  *
1194  * @return bool
1195  */
1196 function wfReadOnly() {
1197         return MediaWikiServices::getInstance()->getReadOnlyMode()
1198                 ->isReadOnly();
1199 }
1200
1201 /**
1202  * Check if the site is in read-only mode and return the message if so
1203  *
1204  * This checks wfConfiguredReadOnlyReason() and the main load balancer
1205  * for replica DB lag. This may result in DB connection being made.
1206  *
1207  * @return string|bool String when in read-only mode; false otherwise
1208  */
1209 function wfReadOnlyReason() {
1210         return MediaWikiServices::getInstance()->getReadOnlyMode()
1211                 ->getReason();
1212 }
1213
1214 /**
1215  * Get the value of $wgReadOnly or the contents of $wgReadOnlyFile.
1216  *
1217  * @return string|bool String when in read-only mode; false otherwise
1218  * @since 1.27
1219  */
1220 function wfConfiguredReadOnlyReason() {
1221         return MediaWikiServices::getInstance()->getConfiguredReadOnlyMode()
1222                 ->getReason();
1223 }
1224
1225 /**
1226  * Return a Language object from $langcode
1227  *
1228  * @param Language|string|bool $langcode Either:
1229  *                  - a Language object
1230  *                  - code of the language to get the message for, if it is
1231  *                    a valid code create a language for that language, if
1232  *                    it is a string but not a valid code then make a basic
1233  *                    language object
1234  *                  - a boolean: if it's false then use the global object for
1235  *                    the current user's language (as a fallback for the old parameter
1236  *                    functionality), or if it is true then use global object
1237  *                    for the wiki's content language.
1238  * @return Language
1239  */
1240 function wfGetLangObj( $langcode = false ) {
1241         # Identify which language to get or create a language object for.
1242         # Using is_object here due to Stub objects.
1243         if ( is_object( $langcode ) ) {
1244                 # Great, we already have the object (hopefully)!
1245                 return $langcode;
1246         }
1247
1248         global $wgLanguageCode;
1249         if ( $langcode === true || $langcode === $wgLanguageCode ) {
1250                 # $langcode is the language code of the wikis content language object.
1251                 # or it is a boolean and value is true
1252                 return MediaWikiServices::getInstance()->getContentLanguage();
1253         }
1254
1255         global $wgLang;
1256         if ( $langcode === false || $langcode === $wgLang->getCode() ) {
1257                 # $langcode is the language code of user language object.
1258                 # or it was a boolean and value is false
1259                 return $wgLang;
1260         }
1261
1262         $validCodes = array_keys( Language::fetchLanguageNames() );
1263         if ( in_array( $langcode, $validCodes ) ) {
1264                 # $langcode corresponds to a valid language.
1265                 return Language::factory( $langcode );
1266         }
1267
1268         # $langcode is a string, but not a valid language code; use content language.
1269         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
1270         return MediaWikiServices::getInstance()->getContentLanguage();
1271 }
1272
1273 /**
1274  * This is the function for getting translated interface messages.
1275  *
1276  * @see Message class for documentation how to use them.
1277  * @see https://www.mediawiki.org/wiki/Manual:Messages_API
1278  *
1279  * This function replaces all old wfMsg* functions.
1280  *
1281  * @param string|string[]|MessageSpecifier $key Message key, or array of keys, or a MessageSpecifier
1282  * @param string|string[] ...$params Normal message parameters
1283  * @return Message
1284  *
1285  * @since 1.17
1286  *
1287  * @see Message::__construct
1288  */
1289 function wfMessage( $key, ...$params ) {
1290         $message = new Message( $key );
1291
1292         // We call Message::params() to reduce code duplication
1293         if ( $params ) {
1294                 $message->params( ...$params );
1295         }
1296
1297         return $message;
1298 }
1299
1300 /**
1301  * This function accepts multiple message keys and returns a message instance
1302  * for the first message which is non-empty. If all messages are empty then an
1303  * instance of the first message key is returned.
1304  *
1305  * @param string ...$keys Message keys
1306  * @return Message
1307  *
1308  * @since 1.18
1309  *
1310  * @see Message::newFallbackSequence
1311  */
1312 function wfMessageFallback( ...$keys ) {
1313         return Message::newFallbackSequence( ...$keys );
1314 }
1315
1316 /**
1317  * Replace message parameter keys on the given formatted output.
1318  *
1319  * @param string $message
1320  * @param array $args
1321  * @return string
1322  * @private
1323  */
1324 function wfMsgReplaceArgs( $message, $args ) {
1325         # Fix windows line-endings
1326         # Some messages are split with explode("\n", $msg)
1327         $message = str_replace( "\r", '', $message );
1328
1329         // Replace arguments
1330         if ( is_array( $args ) && $args ) {
1331                 if ( is_array( $args[0] ) ) {
1332                         $args = array_values( $args[0] );
1333                 }
1334                 $replacementKeys = [];
1335                 foreach ( $args as $n => $param ) {
1336                         $replacementKeys['$' . ( $n + 1 )] = $param;
1337                 }
1338                 $message = strtr( $message, $replacementKeys );
1339         }
1340
1341         return $message;
1342 }
1343
1344 /**
1345  * Fetch server name for use in error reporting etc.
1346  * Use real server name if available, so we know which machine
1347  * in a server farm generated the current page.
1348  *
1349  * @return string
1350  */
1351 function wfHostname() {
1352         static $host;
1353         if ( is_null( $host ) ) {
1354                 # Hostname overriding
1355                 global $wgOverrideHostname;
1356                 if ( $wgOverrideHostname !== false ) {
1357                         # Set static and skip any detection
1358                         $host = $wgOverrideHostname;
1359                         return $host;
1360                 }
1361
1362                 if ( function_exists( 'posix_uname' ) ) {
1363                         // This function not present on Windows
1364                         $uname = posix_uname();
1365                 } else {
1366                         $uname = false;
1367                 }
1368                 if ( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1369                         $host = $uname['nodename'];
1370                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1371                         # Windows computer name
1372                         $host = getenv( 'COMPUTERNAME' );
1373                 } else {
1374                         # This may be a virtual server.
1375                         $host = $_SERVER['SERVER_NAME'];
1376                 }
1377         }
1378         return $host;
1379 }
1380
1381 /**
1382  * Returns a script tag that stores the amount of time it took MediaWiki to
1383  * handle the request in milliseconds as 'wgBackendResponseTime'.
1384  *
1385  * If $wgShowHostnames is true, the script will also set 'wgHostname' to the
1386  * hostname of the server handling the request.
1387  *
1388  * @param string|null $nonce Value from OutputPage::getCSPNonce
1389  * @return string|WrappedString HTML
1390  */
1391 function wfReportTime( $nonce = null ) {
1392         global $wgShowHostnames;
1393
1394         $elapsed = ( microtime( true ) - $_SERVER['REQUEST_TIME_FLOAT'] );
1395         // seconds to milliseconds
1396         $responseTime = round( $elapsed * 1000 );
1397         $reportVars = [ 'wgBackendResponseTime' => $responseTime ];
1398         if ( $wgShowHostnames ) {
1399                 $reportVars['wgHostname'] = wfHostname();
1400         }
1401         return Skin::makeVariablesScript( $reportVars, $nonce );
1402 }
1403
1404 /**
1405  * Safety wrapper for debug_backtrace().
1406  *
1407  * Will return an empty array if debug_backtrace is disabled, otherwise
1408  * the output from debug_backtrace() (trimmed).
1409  *
1410  * @param int $limit This parameter can be used to limit the number of stack frames returned
1411  *
1412  * @return array Array of backtrace information
1413  */
1414 function wfDebugBacktrace( $limit = 0 ) {
1415         static $disabled = null;
1416
1417         if ( is_null( $disabled ) ) {
1418                 $disabled = !function_exists( 'debug_backtrace' );
1419                 if ( $disabled ) {
1420                         wfDebug( "debug_backtrace() is disabled\n" );
1421                 }
1422         }
1423         if ( $disabled ) {
1424                 return [];
1425         }
1426
1427         if ( $limit ) {
1428                 return array_slice( debug_backtrace( DEBUG_BACKTRACE_PROVIDE_OBJECT, $limit + 1 ), 1 );
1429         } else {
1430                 return array_slice( debug_backtrace(), 1 );
1431         }
1432 }
1433
1434 /**
1435  * Get a debug backtrace as a string
1436  *
1437  * @param bool|null $raw If true, the return value is plain text. If false, HTML.
1438  *   Defaults to $wgCommandLineMode if unset.
1439  * @return string
1440  * @since 1.25 Supports $raw parameter.
1441  */
1442 function wfBacktrace( $raw = null ) {
1443         global $wgCommandLineMode;
1444
1445         if ( $raw === null ) {
1446                 $raw = $wgCommandLineMode;
1447         }
1448
1449         if ( $raw ) {
1450                 $frameFormat = "%s line %s calls %s()\n";
1451                 $traceFormat = "%s";
1452         } else {
1453                 $frameFormat = "<li>%s line %s calls %s()</li>\n";
1454                 $traceFormat = "<ul>\n%s</ul>\n";
1455         }
1456
1457         $frames = array_map( function ( $frame ) use ( $frameFormat ) {
1458                 $file = !empty( $frame['file'] ) ? basename( $frame['file'] ) : '-';
1459                 $line = $frame['line'] ?? '-';
1460                 $call = $frame['function'];
1461                 if ( !empty( $frame['class'] ) ) {
1462                         $call = $frame['class'] . $frame['type'] . $call;
1463                 }
1464                 return sprintf( $frameFormat, $file, $line, $call );
1465         }, wfDebugBacktrace() );
1466
1467         return sprintf( $traceFormat, implode( '', $frames ) );
1468 }
1469
1470 /**
1471  * Get the name of the function which called this function
1472  * wfGetCaller( 1 ) is the function with the wfGetCaller() call (ie. __FUNCTION__)
1473  * wfGetCaller( 2 ) [default] is the caller of the function running wfGetCaller()
1474  * wfGetCaller( 3 ) is the parent of that.
1475  *
1476  * @param int $level
1477  * @return string
1478  */
1479 function wfGetCaller( $level = 2 ) {
1480         $backtrace = wfDebugBacktrace( $level + 1 );
1481         if ( isset( $backtrace[$level] ) ) {
1482                 return wfFormatStackFrame( $backtrace[$level] );
1483         } else {
1484                 return 'unknown';
1485         }
1486 }
1487
1488 /**
1489  * Return a string consisting of callers in the stack. Useful sometimes
1490  * for profiling specific points.
1491  *
1492  * @param int $limit The maximum depth of the stack frame to return, or false for the entire stack.
1493  * @return string
1494  */
1495 function wfGetAllCallers( $limit = 3 ) {
1496         $trace = array_reverse( wfDebugBacktrace() );
1497         if ( !$limit || $limit > count( $trace ) - 1 ) {
1498                 $limit = count( $trace ) - 1;
1499         }
1500         $trace = array_slice( $trace, -$limit - 1, $limit );
1501         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1502 }
1503
1504 /**
1505  * Return a string representation of frame
1506  *
1507  * @param array $frame
1508  * @return string
1509  */
1510 function wfFormatStackFrame( $frame ) {
1511         if ( !isset( $frame['function'] ) ) {
1512                 return 'NO_FUNCTION_GIVEN';
1513         }
1514         return isset( $frame['class'] ) && isset( $frame['type'] ) ?
1515                 $frame['class'] . $frame['type'] . $frame['function'] :
1516                 $frame['function'];
1517 }
1518
1519 /* Some generic result counters, pulled out of SearchEngine */
1520
1521 /**
1522  * @todo document
1523  *
1524  * @param int $offset
1525  * @param int $limit
1526  * @return string
1527  */
1528 function wfShowingResults( $offset, $limit ) {
1529         return wfMessage( 'showingresults' )->numParams( $limit, $offset + 1 )->parse();
1530 }
1531
1532 /**
1533  * Whether the client accept gzip encoding
1534  *
1535  * Uses the Accept-Encoding header to check if the client supports gzip encoding.
1536  * Use this when considering to send a gzip-encoded response to the client.
1537  *
1538  * @param bool $force Forces another check even if we already have a cached result.
1539  * @return bool
1540  */
1541 function wfClientAcceptsGzip( $force = false ) {
1542         static $result = null;
1543         if ( $result === null || $force ) {
1544                 $result = false;
1545                 if ( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1546                         # @todo FIXME: We may want to blacklist some broken browsers
1547                         $m = [];
1548                         if ( preg_match(
1549                                         '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1550                                         $_SERVER['HTTP_ACCEPT_ENCODING'],
1551                                         $m
1552                                 )
1553                         ) {
1554                                 if ( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1555                                         $result = false;
1556                                         return $result;
1557                                 }
1558                                 wfDebug( "wfClientAcceptsGzip: client accepts gzip.\n" );
1559                                 $result = true;
1560                         }
1561                 }
1562         }
1563         return $result;
1564 }
1565
1566 /**
1567  * Escapes the given text so that it may be output using addWikiText()
1568  * without any linking, formatting, etc. making its way through. This
1569  * is achieved by substituting certain characters with HTML entities.
1570  * As required by the callers, "<nowiki>" is not used.
1571  *
1572  * @param string $text Text to be escaped
1573  * @param-taint $text escapes_html
1574  * @return string
1575  */
1576 function wfEscapeWikiText( $text ) {
1577         global $wgEnableMagicLinks;
1578         static $repl = null, $repl2 = null;
1579         if ( $repl === null || defined( 'MW_PARSER_TEST' ) || defined( 'MW_PHPUNIT_TEST' ) ) {
1580                 // Tests depend upon being able to change $wgEnableMagicLinks, so don't cache
1581                 // in those situations
1582                 $repl = [
1583                         '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
1584                         '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
1585                         '{' => '&#123;', '|' => '&#124;', '}' => '&#125;', ';' => '&#59;',
1586                         "\n#" => "\n&#35;", "\r#" => "\r&#35;",
1587                         "\n*" => "\n&#42;", "\r*" => "\r&#42;",
1588                         "\n:" => "\n&#58;", "\r:" => "\r&#58;",
1589                         "\n " => "\n&#32;", "\r " => "\r&#32;",
1590                         "\n\n" => "\n&#10;", "\r\n" => "&#13;\n",
1591                         "\n\r" => "\n&#13;", "\r\r" => "\r&#13;",
1592                         "\n\t" => "\n&#9;", "\r\t" => "\r&#9;", // "\n\t\n" is treated like "\n\n"
1593                         "\n----" => "\n&#45;---", "\r----" => "\r&#45;---",
1594                         '__' => '_&#95;', '://' => '&#58;//',
1595                 ];
1596
1597                 $magicLinks = array_keys( array_filter( $wgEnableMagicLinks ) );
1598                 // We have to catch everything "\s" matches in PCRE
1599                 foreach ( $magicLinks as $magic ) {
1600                         $repl["$magic "] = "$magic&#32;";
1601                         $repl["$magic\t"] = "$magic&#9;";
1602                         $repl["$magic\r"] = "$magic&#13;";
1603                         $repl["$magic\n"] = "$magic&#10;";
1604                         $repl["$magic\f"] = "$magic&#12;";
1605                 }
1606
1607                 // And handle protocols that don't use "://"
1608                 global $wgUrlProtocols;
1609                 $repl2 = [];
1610                 foreach ( $wgUrlProtocols as $prot ) {
1611                         if ( substr( $prot, -1 ) === ':' ) {
1612                                 $repl2[] = preg_quote( substr( $prot, 0, -1 ), '/' );
1613                         }
1614                 }
1615                 $repl2 = $repl2 ? '/\b(' . implode( '|', $repl2 ) . '):/i' : '/^(?!)/';
1616         }
1617         $text = substr( strtr( "\n$text", $repl ), 1 );
1618         $text = preg_replace( $repl2, '$1&#58;', $text );
1619         return $text;
1620 }
1621
1622 /**
1623  * Sets dest to source and returns the original value of dest
1624  * If source is NULL, it just returns the value, it doesn't set the variable
1625  * If force is true, it will set the value even if source is NULL
1626  *
1627  * @param mixed &$dest
1628  * @param mixed $source
1629  * @param bool $force
1630  * @return mixed
1631  */
1632 function wfSetVar( &$dest, $source, $force = false ) {
1633         $temp = $dest;
1634         if ( !is_null( $source ) || $force ) {
1635                 $dest = $source;
1636         }
1637         return $temp;
1638 }
1639
1640 /**
1641  * As for wfSetVar except setting a bit
1642  *
1643  * @param int &$dest
1644  * @param int $bit
1645  * @param bool $state
1646  *
1647  * @return bool
1648  */
1649 function wfSetBit( &$dest, $bit, $state = true ) {
1650         $temp = (bool)( $dest & $bit );
1651         if ( !is_null( $state ) ) {
1652                 if ( $state ) {
1653                         $dest |= $bit;
1654                 } else {
1655                         $dest &= ~$bit;
1656                 }
1657         }
1658         return $temp;
1659 }
1660
1661 /**
1662  * A wrapper around the PHP function var_export().
1663  * Either print it or add it to the regular output ($wgOut).
1664  *
1665  * @param mixed $var A PHP variable to dump.
1666  */
1667 function wfVarDump( $var ) {
1668         global $wgOut;
1669         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
1670         if ( headers_sent() || !isset( $wgOut ) || !is_object( $wgOut ) ) {
1671                 print $s;
1672         } else {
1673                 $wgOut->addHTML( $s );
1674         }
1675 }
1676
1677 /**
1678  * Provide a simple HTTP error.
1679  *
1680  * @param int|string $code
1681  * @param string $label
1682  * @param string $desc
1683  */
1684 function wfHttpError( $code, $label, $desc ) {
1685         global $wgOut;
1686         HttpStatus::header( $code );
1687         if ( $wgOut ) {
1688                 $wgOut->disable();
1689                 $wgOut->sendCacheControl();
1690         }
1691
1692         MediaWiki\HeaderCallback::warnIfHeadersSent();
1693         header( 'Content-type: text/html; charset=utf-8' );
1694         print '<!DOCTYPE html>' .
1695                 '<html><head><title>' .
1696                 htmlspecialchars( $label ) .
1697                 '</title></head><body><h1>' .
1698                 htmlspecialchars( $label ) .
1699                 '</h1><p>' .
1700                 nl2br( htmlspecialchars( $desc ) ) .
1701                 "</p></body></html>\n";
1702 }
1703
1704 /**
1705  * Clear away any user-level output buffers, discarding contents.
1706  *
1707  * Suitable for 'starting afresh', for instance when streaming
1708  * relatively large amounts of data without buffering, or wanting to
1709  * output image files without ob_gzhandler's compression.
1710  *
1711  * The optional $resetGzipEncoding parameter controls suppression of
1712  * the Content-Encoding header sent by ob_gzhandler; by default it
1713  * is left. See comments for wfClearOutputBuffers() for why it would
1714  * be used.
1715  *
1716  * Note that some PHP configuration options may add output buffer
1717  * layers which cannot be removed; these are left in place.
1718  *
1719  * @param bool $resetGzipEncoding
1720  */
1721 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
1722         if ( $resetGzipEncoding ) {
1723                 // Suppress Content-Encoding and Content-Length
1724                 // headers from OutputHandler::handle.
1725                 global $wgDisableOutputCompression;
1726                 $wgDisableOutputCompression = true;
1727         }
1728         while ( $status = ob_get_status() ) {
1729                 if ( isset( $status['flags'] ) ) {
1730                         $flags = PHP_OUTPUT_HANDLER_CLEANABLE | PHP_OUTPUT_HANDLER_REMOVABLE;
1731                         $deleteable = ( $status['flags'] & $flags ) === $flags;
1732                 } elseif ( isset( $status['del'] ) ) {
1733                         $deleteable = $status['del'];
1734                 } else {
1735                         // Guess that any PHP-internal setting can't be removed.
1736                         $deleteable = $status['type'] !== 0; /* PHP_OUTPUT_HANDLER_INTERNAL */
1737                 }
1738                 if ( !$deleteable ) {
1739                         // Give up, and hope the result doesn't break
1740                         // output behavior.
1741                         break;
1742                 }
1743                 if ( $status['name'] === 'MediaWikiTestCase::wfResetOutputBuffersBarrier' ) {
1744                         // Unit testing barrier to prevent this function from breaking PHPUnit.
1745                         break;
1746                 }
1747                 if ( !ob_end_clean() ) {
1748                         // Could not remove output buffer handler; abort now
1749                         // to avoid getting in some kind of infinite loop.
1750                         break;
1751                 }
1752                 if ( $resetGzipEncoding ) {
1753                         if ( $status['name'] == 'ob_gzhandler' ) {
1754                                 // Reset the 'Content-Encoding' field set by this handler
1755                                 // so we can start fresh.
1756                                 header_remove( 'Content-Encoding' );
1757                                 break;
1758                         }
1759                 }
1760         }
1761 }
1762
1763 /**
1764  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
1765  *
1766  * Clear away output buffers, but keep the Content-Encoding header
1767  * produced by ob_gzhandler, if any.
1768  *
1769  * This should be used for HTTP 304 responses, where you need to
1770  * preserve the Content-Encoding header of the real result, but
1771  * also need to suppress the output of ob_gzhandler to keep to spec
1772  * and avoid breaking Firefox in rare cases where the headers and
1773  * body are broken over two packets.
1774  */
1775 function wfClearOutputBuffers() {
1776         wfResetOutputBuffers( false );
1777 }
1778
1779 /**
1780  * Converts an Accept-* header into an array mapping string values to quality
1781  * factors
1782  *
1783  * @param string $accept
1784  * @param string $def Default
1785  * @return float[] Associative array of string => float pairs
1786  */
1787 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
1788         # No arg means accept anything (per HTTP spec)
1789         if ( !$accept ) {
1790                 return [ $def => 1.0 ];
1791         }
1792
1793         $prefs = [];
1794
1795         $parts = explode( ',', $accept );
1796
1797         foreach ( $parts as $part ) {
1798                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
1799                 $values = explode( ';', trim( $part ) );
1800                 $match = [];
1801                 if ( count( $values ) == 1 ) {
1802                         $prefs[$values[0]] = 1.0;
1803                 } elseif ( preg_match( '/q\s*=\s*(\d*\.\d+)/', $values[1], $match ) ) {
1804                         $prefs[$values[0]] = floatval( $match[1] );
1805                 }
1806         }
1807
1808         return $prefs;
1809 }
1810
1811 /**
1812  * Checks if a given MIME type matches any of the keys in the given
1813  * array. Basic wildcards are accepted in the array keys.
1814  *
1815  * Returns the matching MIME type (or wildcard) if a match, otherwise
1816  * NULL if no match.
1817  *
1818  * @param string $type
1819  * @param array $avail
1820  * @return string
1821  * @private
1822  */
1823 function mimeTypeMatch( $type, $avail ) {
1824         if ( array_key_exists( $type, $avail ) ) {
1825                 return $type;
1826         } else {
1827                 $mainType = explode( '/', $type )[0];
1828                 if ( array_key_exists( "$mainType/*", $avail ) ) {
1829                         return "$mainType/*";
1830                 } elseif ( array_key_exists( '*/*', $avail ) ) {
1831                         return '*/*';
1832                 } else {
1833                         return null;
1834                 }
1835         }
1836 }
1837
1838 /**
1839  * Returns the 'best' match between a client's requested internet media types
1840  * and the server's list of available types. Each list should be an associative
1841  * array of type to preference (preference is a float between 0.0 and 1.0).
1842  * Wildcards in the types are acceptable.
1843  *
1844  * @param array $cprefs Client's acceptable type list
1845  * @param array $sprefs Server's offered types
1846  * @return string
1847  *
1848  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
1849  * XXX: generalize to negotiate other stuff
1850  */
1851 function wfNegotiateType( $cprefs, $sprefs ) {
1852         $combine = [];
1853
1854         foreach ( array_keys( $sprefs ) as $type ) {
1855                 $subType = explode( '/', $type )[1];
1856                 if ( $subType != '*' ) {
1857                         $ckey = mimeTypeMatch( $type, $cprefs );
1858                         if ( $ckey ) {
1859                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
1860                         }
1861                 }
1862         }
1863
1864         foreach ( array_keys( $cprefs ) as $type ) {
1865                 $subType = explode( '/', $type )[1];
1866                 if ( $subType != '*' && !array_key_exists( $type, $sprefs ) ) {
1867                         $skey = mimeTypeMatch( $type, $sprefs );
1868                         if ( $skey ) {
1869                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
1870                         }
1871                 }
1872         }
1873
1874         $bestq = 0;
1875         $besttype = null;
1876
1877         foreach ( array_keys( $combine ) as $type ) {
1878                 if ( $combine[$type] > $bestq ) {
1879                         $besttype = $type;
1880                         $bestq = $combine[$type];
1881                 }
1882         }
1883
1884         return $besttype;
1885 }
1886
1887 /**
1888  * Reference-counted warning suppression
1889  *
1890  * @deprecated since 1.26, use Wikimedia\suppressWarnings() directly
1891  * @param bool $end
1892  */
1893 function wfSuppressWarnings( $end = false ) {
1894         Wikimedia\suppressWarnings( $end );
1895 }
1896
1897 /**
1898  * @deprecated since 1.26, use Wikimedia\restoreWarnings() directly
1899  * Restore error level to previous value
1900  */
1901 function wfRestoreWarnings() {
1902         Wikimedia\restoreWarnings();
1903 }
1904
1905 /**
1906  * Get a timestamp string in one of various formats
1907  *
1908  * @param mixed $outputtype A timestamp in one of the supported formats, the
1909  *   function will autodetect which format is supplied and act accordingly.
1910  * @param mixed $ts Optional timestamp to convert, default 0 for the current time
1911  * @return string|bool String / false The same date in the format specified in $outputtype or false
1912  */
1913 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
1914         $ret = MWTimestamp::convert( $outputtype, $ts );
1915         if ( $ret === false ) {
1916                 wfDebug( "wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n" );
1917         }
1918         return $ret;
1919 }
1920
1921 /**
1922  * Return a formatted timestamp, or null if input is null.
1923  * For dealing with nullable timestamp columns in the database.
1924  *
1925  * @param int $outputtype
1926  * @param string|null $ts
1927  * @return string
1928  */
1929 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
1930         if ( is_null( $ts ) ) {
1931                 return null;
1932         } else {
1933                 return wfTimestamp( $outputtype, $ts );
1934         }
1935 }
1936
1937 /**
1938  * Convenience function; returns MediaWiki timestamp for the present time.
1939  *
1940  * @return string
1941  */
1942 function wfTimestampNow() {
1943         # return NOW
1944         return MWTimestamp::now( TS_MW );
1945 }
1946
1947 /**
1948  * Check if the operating system is Windows
1949  *
1950  * @return bool True if it's Windows, false otherwise.
1951  */
1952 function wfIsWindows() {
1953         static $isWindows = null;
1954         if ( $isWindows === null ) {
1955                 $isWindows = strtoupper( substr( PHP_OS, 0, 3 ) ) === 'WIN';
1956         }
1957         return $isWindows;
1958 }
1959
1960 /**
1961  * Check if we are running under HHVM
1962  *
1963  * @return bool
1964  */
1965 function wfIsHHVM() {
1966         return defined( 'HHVM_VERSION' );
1967 }
1968
1969 /**
1970  * Check if we are running from the commandline
1971  *
1972  * @since 1.31
1973  * @return bool
1974  */
1975 function wfIsCLI() {
1976         return PHP_SAPI === 'cli' || PHP_SAPI === 'phpdbg';
1977 }
1978
1979 /**
1980  * Tries to get the system directory for temporary files. First
1981  * $wgTmpDirectory is checked, and then the TMPDIR, TMP, and TEMP
1982  * environment variables are then checked in sequence, then
1983  * sys_get_temp_dir(), then upload_tmp_dir from php.ini.
1984  *
1985  * NOTE: When possible, use instead the tmpfile() function to create
1986  * temporary files to avoid race conditions on file creation, etc.
1987  *
1988  * @return string
1989  */
1990 function wfTempDir() {
1991         global $wgTmpDirectory;
1992
1993         if ( $wgTmpDirectory !== false ) {
1994                 return $wgTmpDirectory;
1995         }
1996
1997         return TempFSFile::getUsableTempDirectory();
1998 }
1999
2000 /**
2001  * Make directory, and make all parent directories if they don't exist
2002  *
2003  * @param string $dir Full path to directory to create
2004  * @param int|null $mode Chmod value to use, default is $wgDirectoryMode
2005  * @param string|null $caller Optional caller param for debugging.
2006  * @throws MWException
2007  * @return bool
2008  */
2009 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2010         global $wgDirectoryMode;
2011
2012         if ( FileBackend::isStoragePath( $dir ) ) { // sanity
2013                 throw new MWException( __FUNCTION__ . " given storage path '$dir'." );
2014         }
2015
2016         if ( !is_null( $caller ) ) {
2017                 wfDebug( "$caller: called wfMkdirParents($dir)\n" );
2018         }
2019
2020         if ( strval( $dir ) === '' || is_dir( $dir ) ) {
2021                 return true;
2022         }
2023
2024         $dir = str_replace( [ '\\', '/' ], DIRECTORY_SEPARATOR, $dir );
2025
2026         if ( is_null( $mode ) ) {
2027                 $mode = $wgDirectoryMode;
2028         }
2029
2030         // Turn off the normal warning, we're doing our own below
2031         Wikimedia\suppressWarnings();
2032         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2033         Wikimedia\restoreWarnings();
2034
2035         if ( !$ok ) {
2036                 // directory may have been created on another request since we last checked
2037                 if ( is_dir( $dir ) ) {
2038                         return true;
2039                 }
2040
2041                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2042                 wfLogWarning( sprintf( "failed to mkdir \"%s\" mode 0%o", $dir, $mode ) );
2043         }
2044         return $ok;
2045 }
2046
2047 /**
2048  * Remove a directory and all its content.
2049  * Does not hide error.
2050  * @param string $dir
2051  */
2052 function wfRecursiveRemoveDir( $dir ) {
2053         wfDebug( __FUNCTION__ . "( $dir )\n" );
2054         // taken from https://secure.php.net/manual/en/function.rmdir.php#98622
2055         if ( is_dir( $dir ) ) {
2056                 $objects = scandir( $dir );
2057                 foreach ( $objects as $object ) {
2058                         if ( $object != "." && $object != ".." ) {
2059                                 if ( filetype( $dir . '/' . $object ) == "dir" ) {
2060                                         wfRecursiveRemoveDir( $dir . '/' . $object );
2061                                 } else {
2062                                         unlink( $dir . '/' . $object );
2063                                 }
2064                         }
2065                 }
2066                 reset( $objects );
2067                 rmdir( $dir );
2068         }
2069 }
2070
2071 /**
2072  * @param int $nr The number to format
2073  * @param int $acc The number of digits after the decimal point, default 2
2074  * @param bool $round Whether or not to round the value, default true
2075  * @return string
2076  */
2077 function wfPercent( $nr, $acc = 2, $round = true ) {
2078         $ret = sprintf( "%.${acc}f", $nr );
2079         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2080 }
2081
2082 /**
2083  * Safety wrapper around ini_get() for boolean settings.
2084  * The values returned from ini_get() are pre-normalized for settings
2085  * set via php.ini or php_flag/php_admin_flag... but *not*
2086  * for those set via php_value/php_admin_value.
2087  *
2088  * It's fairly common for people to use php_value instead of php_flag,
2089  * which can leave you with an 'off' setting giving a false positive
2090  * for code that just takes the ini_get() return value as a boolean.
2091  *
2092  * To make things extra interesting, setting via php_value accepts
2093  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2094  * Unrecognized values go false... again opposite PHP's own coercion
2095  * from string to bool.
2096  *
2097  * Luckily, 'properly' set settings will always come back as '0' or '1',
2098  * so we only have to worry about them and the 'improper' settings.
2099  *
2100  * I frickin' hate PHP... :P
2101  *
2102  * @param string $setting
2103  * @return bool
2104  */
2105 function wfIniGetBool( $setting ) {
2106         return wfStringToBool( ini_get( $setting ) );
2107 }
2108
2109 /**
2110  * Convert string value to boolean, when the following are interpreted as true:
2111  * - on
2112  * - true
2113  * - yes
2114  * - Any number, except 0
2115  * All other strings are interpreted as false.
2116  *
2117  * @param string $val
2118  * @return bool
2119  * @since 1.31
2120  */
2121 function wfStringToBool( $val ) {
2122         $val = strtolower( $val );
2123         // 'on' and 'true' can't have whitespace around them, but '1' can.
2124         return $val == 'on'
2125                 || $val == 'true'
2126                 || $val == 'yes'
2127                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2128 }
2129
2130 /**
2131  * Version of escapeshellarg() that works better on Windows.
2132  *
2133  * Originally, this fixed the incorrect use of single quotes on Windows
2134  * (https://bugs.php.net/bug.php?id=26285) and the locale problems on Linux in
2135  * PHP 5.2.6+ (bug backported to earlier distro releases of PHP).
2136  *
2137  * @param string|string[] ...$args strings to escape and glue together,
2138  *  or a single array of strings parameter
2139  * @return string
2140  * @deprecated since 1.30 use MediaWiki\Shell::escape()
2141  */
2142 function wfEscapeShellArg( ...$args ) {
2143         return Shell::escape( ...$args );
2144 }
2145
2146 /**
2147  * Execute a shell command, with time and memory limits mirrored from the PHP
2148  * configuration if supported.
2149  *
2150  * @param string|string[] $cmd If string, a properly shell-escaped command line,
2151  *   or an array of unescaped arguments, in which case each value will be escaped
2152  *   Example:   [ 'convert', '-font', 'font name' ] would produce "'convert' '-font' 'font name'"
2153  * @param null|mixed &$retval Optional, will receive the program's exit code.
2154  *   (non-zero is usually failure). If there is an error from
2155  *   read, select, or proc_open(), this will be set to -1.
2156  * @param array $environ Optional environment variables which should be
2157  *   added to the executed command environment.
2158  * @param array $limits Optional array with limits(filesize, memory, time, walltime)
2159  *   this overwrites the global wgMaxShell* limits.
2160  * @param array $options Array of options:
2161  *   - duplicateStderr: Set this to true to duplicate stderr to stdout,
2162  *     including errors from limit.sh
2163  *   - profileMethod: By default this function will profile based on the calling
2164  *     method. Set this to a string for an alternative method to profile from
2165  *
2166  * @return string Collected stdout as a string
2167  * @deprecated since 1.30 use class MediaWiki\Shell\Shell
2168  */
2169 function wfShellExec( $cmd, &$retval = null, $environ = [],
2170         $limits = [], $options = []
2171 ) {
2172         if ( Shell::isDisabled() ) {
2173                 $retval = 1;
2174                 // Backwards compatibility be upon us...
2175                 return 'Unable to run external programs, proc_open() is disabled.';
2176         }
2177
2178         if ( is_array( $cmd ) ) {
2179                 $cmd = Shell::escape( $cmd );
2180         }
2181
2182         $includeStderr = isset( $options['duplicateStderr'] ) && $options['duplicateStderr'];
2183         $profileMethod = $options['profileMethod'] ?? wfGetCaller();
2184
2185         try {
2186                 $result = Shell::command( [] )
2187                         ->unsafeParams( (array)$cmd )
2188                         ->environment( $environ )
2189                         ->limits( $limits )
2190                         ->includeStderr( $includeStderr )
2191                         ->profileMethod( $profileMethod )
2192                         // For b/c
2193                         ->restrict( Shell::RESTRICT_NONE )
2194                         ->execute();
2195         } catch ( ProcOpenError $ex ) {
2196                 $retval = -1;
2197                 return '';
2198         }
2199
2200         $retval = $result->getExitCode();
2201
2202         return $result->getStdout();
2203 }
2204
2205 /**
2206  * Execute a shell command, returning both stdout and stderr. Convenience
2207  * function, as all the arguments to wfShellExec can become unwieldy.
2208  *
2209  * @note This also includes errors from limit.sh, e.g. if $wgMaxShellFileSize is exceeded.
2210  * @param string|string[] $cmd If string, a properly shell-escaped command line,
2211  *   or an array of unescaped arguments, in which case each value will be escaped
2212  *   Example:   [ 'convert', '-font', 'font name' ] would produce "'convert' '-font' 'font name'"
2213  * @param null|mixed &$retval Optional, will receive the program's exit code.
2214  *   (non-zero is usually failure)
2215  * @param array $environ Optional environment variables which should be
2216  *   added to the executed command environment.
2217  * @param array $limits Optional array with limits(filesize, memory, time, walltime)
2218  *   this overwrites the global wgMaxShell* limits.
2219  * @return string Collected stdout and stderr as a string
2220  * @deprecated since 1.30 use class MediaWiki\Shell\Shell
2221  */
2222 function wfShellExecWithStderr( $cmd, &$retval = null, $environ = [], $limits = [] ) {
2223         return wfShellExec( $cmd, $retval, $environ, $limits,
2224                 [ 'duplicateStderr' => true, 'profileMethod' => wfGetCaller() ] );
2225 }
2226
2227 /**
2228  * Generate a shell-escaped command line string to run a MediaWiki cli script.
2229  * Note that $parameters should be a flat array and an option with an argument
2230  * should consist of two consecutive items in the array (do not use "--option value").
2231  *
2232  * @deprecated since 1.31, use Shell::makeScriptCommand()
2233  *
2234  * @param string $script MediaWiki cli script path
2235  * @param array $parameters Arguments and options to the script
2236  * @param array $options Associative array of options:
2237  *     'php': The path to the php executable
2238  *     'wrapper': Path to a PHP wrapper to handle the maintenance script
2239  * @return string
2240  */
2241 function wfShellWikiCmd( $script, array $parameters = [], array $options = [] ) {
2242         global $wgPhpCli;
2243         // Give site config file a chance to run the script in a wrapper.
2244         // The caller may likely want to call wfBasename() on $script.
2245         Hooks::run( 'wfShellWikiCmd', [ &$script, &$parameters, &$options ] );
2246         $cmd = [ $options['php'] ?? $wgPhpCli ];
2247         if ( isset( $options['wrapper'] ) ) {
2248                 $cmd[] = $options['wrapper'];
2249         }
2250         $cmd[] = $script;
2251         // Escape each parameter for shell
2252         return Shell::escape( array_merge( $cmd, $parameters ) );
2253 }
2254
2255 /**
2256  * wfMerge attempts to merge differences between three texts.
2257  * Returns true for a clean merge and false for failure or a conflict.
2258  *
2259  * @param string $old
2260  * @param string $mine
2261  * @param string $yours
2262  * @param string &$result
2263  * @param string|null &$mergeAttemptResult
2264  * @return bool
2265  */
2266 function wfMerge( $old, $mine, $yours, &$result, &$mergeAttemptResult = null ) {
2267         global $wgDiff3;
2268
2269         # This check may also protect against code injection in
2270         # case of broken installations.
2271         Wikimedia\suppressWarnings();
2272         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
2273         Wikimedia\restoreWarnings();
2274
2275         if ( !$haveDiff3 ) {
2276                 wfDebug( "diff3 not found\n" );
2277                 return false;
2278         }
2279
2280         # Make temporary files
2281         $td = wfTempDir();
2282         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
2283         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
2284         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
2285
2286         # NOTE: diff3 issues a warning to stderr if any of the files does not end with
2287         #       a newline character. To avoid this, we normalize the trailing whitespace before
2288         #       creating the diff.
2289
2290         fwrite( $oldtextFile, rtrim( $old ) . "\n" );
2291         fclose( $oldtextFile );
2292         fwrite( $mytextFile, rtrim( $mine ) . "\n" );
2293         fclose( $mytextFile );
2294         fwrite( $yourtextFile, rtrim( $yours ) . "\n" );
2295         fclose( $yourtextFile );
2296
2297         # Check for a conflict
2298         $cmd = Shell::escape( $wgDiff3, '-a', '--overlap-only', $mytextName,
2299                 $oldtextName, $yourtextName );
2300         $handle = popen( $cmd, 'r' );
2301
2302         $mergeAttemptResult = '';
2303         do {
2304                 $data = fread( $handle, 8192 );
2305                 if ( strlen( $data ) == 0 ) {
2306                         break;
2307                 }
2308                 $mergeAttemptResult .= $data;
2309         } while ( true );
2310         pclose( $handle );
2311
2312         $conflict = $mergeAttemptResult !== '';
2313
2314         # Merge differences
2315         $cmd = Shell::escape( $wgDiff3, '-a', '-e', '--merge', $mytextName,
2316                 $oldtextName, $yourtextName );
2317         $handle = popen( $cmd, 'r' );
2318         $result = '';
2319         do {
2320                 $data = fread( $handle, 8192 );
2321                 if ( strlen( $data ) == 0 ) {
2322                         break;
2323                 }
2324                 $result .= $data;
2325         } while ( true );
2326         pclose( $handle );
2327         unlink( $mytextName );
2328         unlink( $oldtextName );
2329         unlink( $yourtextName );
2330
2331         if ( $result === '' && $old !== '' && !$conflict ) {
2332                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
2333                 $conflict = true;
2334         }
2335         return !$conflict;
2336 }
2337
2338 /**
2339  * Returns unified plain-text diff of two texts.
2340  * "Useful" for machine processing of diffs.
2341  *
2342  * @deprecated since 1.25, use DiffEngine/UnifiedDiffFormatter directly
2343  *
2344  * @param string $before The text before the changes.
2345  * @param string $after The text after the changes.
2346  * @param string $params Command-line options for the diff command.
2347  * @return string Unified diff of $before and $after
2348  */
2349 function wfDiff( $before, $after, $params = '-u' ) {
2350         if ( $before == $after ) {
2351                 return '';
2352         }
2353
2354         global $wgDiff;
2355         Wikimedia\suppressWarnings();
2356         $haveDiff = $wgDiff && file_exists( $wgDiff );
2357         Wikimedia\restoreWarnings();
2358
2359         # This check may also protect against code injection in
2360         # case of broken installations.
2361         if ( !$haveDiff ) {
2362                 wfDebug( "diff executable not found\n" );
2363                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
2364                 $format = new UnifiedDiffFormatter();
2365                 return $format->format( $diffs );
2366         }
2367
2368         # Make temporary files
2369         $td = wfTempDir();
2370         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
2371         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
2372
2373         fwrite( $oldtextFile, $before );
2374         fclose( $oldtextFile );
2375         fwrite( $newtextFile, $after );
2376         fclose( $newtextFile );
2377
2378         // Get the diff of the two files
2379         $cmd = "$wgDiff " . $params . ' ' . Shell::escape( $oldtextName, $newtextName );
2380
2381         $h = popen( $cmd, 'r' );
2382         if ( !$h ) {
2383                 unlink( $oldtextName );
2384                 unlink( $newtextName );
2385                 throw new Exception( __METHOD__ . '(): popen() failed' );
2386         }
2387
2388         $diff = '';
2389
2390         do {
2391                 $data = fread( $h, 8192 );
2392                 if ( strlen( $data ) == 0 ) {
2393                         break;
2394                 }
2395                 $diff .= $data;
2396         } while ( true );
2397
2398         // Clean up
2399         pclose( $h );
2400         unlink( $oldtextName );
2401         unlink( $newtextName );
2402
2403         // Kill the --- and +++ lines. They're not useful.
2404         $diff_lines = explode( "\n", $diff );
2405         if ( isset( $diff_lines[0] ) && strpos( $diff_lines[0], '---' ) === 0 ) {
2406                 unset( $diff_lines[0] );
2407         }
2408         if ( isset( $diff_lines[1] ) && strpos( $diff_lines[1], '+++' ) === 0 ) {
2409                 unset( $diff_lines[1] );
2410         }
2411
2412         $diff = implode( "\n", $diff_lines );
2413
2414         return $diff;
2415 }
2416
2417 /**
2418  * Return the final portion of a pathname.
2419  * Reimplemented because PHP5's "basename()" is buggy with multibyte text.
2420  * https://bugs.php.net/bug.php?id=33898
2421  *
2422  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
2423  * We'll consider it so always, as we don't want '\s' in our Unix paths either.
2424  *
2425  * @param string $path
2426  * @param string $suffix String to remove if present
2427  * @return string
2428  */
2429 function wfBaseName( $path, $suffix = '' ) {
2430         if ( $suffix == '' ) {
2431                 $encSuffix = '';
2432         } else {
2433                 $encSuffix = '(?:' . preg_quote( $suffix, '#' ) . ')?';
2434         }
2435
2436         $matches = [];
2437         if ( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2438                 return $matches[1];
2439         } else {
2440                 return '';
2441         }
2442 }
2443
2444 /**
2445  * Generate a relative path name to the given file.
2446  * May explode on non-matching case-insensitive paths,
2447  * funky symlinks, etc.
2448  *
2449  * @param string $path Absolute destination path including target filename
2450  * @param string $from Absolute source path, directory only
2451  * @return string
2452  */
2453 function wfRelativePath( $path, $from ) {
2454         // Normalize mixed input on Windows...
2455         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2456         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2457
2458         // Trim trailing slashes -- fix for drive root
2459         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2460         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2461
2462         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2463         $against = explode( DIRECTORY_SEPARATOR, $from );
2464
2465         if ( $pieces[0] !== $against[0] ) {
2466                 // Non-matching Windows drive letters?
2467                 // Return a full path.
2468                 return $path;
2469         }
2470
2471         // Trim off common prefix
2472         while ( count( $pieces ) && count( $against )
2473                 && $pieces[0] == $against[0] ) {
2474                 array_shift( $pieces );
2475                 array_shift( $against );
2476         }
2477
2478         // relative dots to bump us to the parent
2479         while ( count( $against ) ) {
2480                 array_unshift( $pieces, '..' );
2481                 array_shift( $against );
2482         }
2483
2484         array_push( $pieces, wfBaseName( $path ) );
2485
2486         return implode( DIRECTORY_SEPARATOR, $pieces );
2487 }
2488
2489 /**
2490  * Reset the session id
2491  *
2492  * @deprecated since 1.27, use MediaWiki\Session\SessionManager instead
2493  * @since 1.22
2494  */
2495 function wfResetSessionID() {
2496         wfDeprecated( __FUNCTION__, '1.27' );
2497         $session = SessionManager::getGlobalSession();
2498         $delay = $session->delaySave();
2499
2500         $session->resetId();
2501
2502         // Make sure a session is started, since that's what the old
2503         // wfResetSessionID() did.
2504         if ( session_id() !== $session->getId() ) {
2505                 wfSetupSession( $session->getId() );
2506         }
2507
2508         ScopedCallback::consume( $delay );
2509 }
2510
2511 /**
2512  * Initialise php session
2513  *
2514  * @deprecated since 1.27, use MediaWiki\Session\SessionManager instead.
2515  *  Generally, "using" SessionManager will be calling ->getSessionById() or
2516  *  ::getGlobalSession() (depending on whether you were passing $sessionId
2517  *  here), then calling $session->persist().
2518  * @param bool|string $sessionId
2519  */
2520 function wfSetupSession( $sessionId = false ) {
2521         wfDeprecated( __FUNCTION__, '1.27' );
2522
2523         if ( $sessionId ) {
2524                 session_id( $sessionId );
2525         }
2526
2527         $session = SessionManager::getGlobalSession();
2528         $session->persist();
2529
2530         if ( session_id() !== $session->getId() ) {
2531                 session_id( $session->getId() );
2532         }
2533         Wikimedia\quietCall( 'session_start' );
2534 }
2535
2536 /**
2537  * Get an object from the precompiled serialized directory
2538  *
2539  * @param string $name
2540  * @return mixed The variable on success, false on failure
2541  */
2542 function wfGetPrecompiledData( $name ) {
2543         global $IP;
2544
2545         $file = "$IP/serialized/$name";
2546         if ( file_exists( $file ) ) {
2547                 $blob = file_get_contents( $file );
2548                 if ( $blob ) {
2549                         return unserialize( $blob );
2550                 }
2551         }
2552         return false;
2553 }
2554
2555 /**
2556  * Make a cache key for the local wiki.
2557  *
2558  * @deprecated since 1.30 Call makeKey on a BagOStuff instance
2559  * @param string ...$args
2560  * @return string
2561  */
2562 function wfMemcKey( ...$args ) {
2563         return ObjectCache::getLocalClusterInstance()->makeKey( ...$args );
2564 }
2565
2566 /**
2567  * Make a cache key for a foreign DB.
2568  *
2569  * Must match what wfMemcKey() would produce in context of the foreign wiki.
2570  *
2571  * @param string $db
2572  * @param string $prefix
2573  * @param string ...$args
2574  * @return string
2575  */
2576 function wfForeignMemcKey( $db, $prefix, ...$args ) {
2577         $keyspace = $prefix ? "$db-$prefix" : $db;
2578         return ObjectCache::getLocalClusterInstance()->makeKeyInternal( $keyspace, $args );
2579 }
2580
2581 /**
2582  * Make a cache key with database-agnostic prefix.
2583  *
2584  * Doesn't have a wiki-specific namespace. Uses a generic 'global' prefix
2585  * instead. Must have a prefix as otherwise keys that use a database name
2586  * in the first segment will clash with wfMemcKey/wfForeignMemcKey.
2587  *
2588  * @deprecated since 1.30 Call makeGlobalKey on a BagOStuff instance
2589  * @since 1.26
2590  * @param string ...$args
2591  * @return string
2592  */
2593 function wfGlobalCacheKey( ...$args ) {
2594         return ObjectCache::getLocalClusterInstance()->makeGlobalKey( ...$args );
2595 }
2596
2597 /**
2598  * Get an ASCII string identifying this wiki
2599  * This is used as a prefix in memcached keys
2600  *
2601  * @return string
2602  */
2603 function wfWikiID() {
2604         global $wgDBprefix, $wgDBname;
2605         if ( $wgDBprefix ) {
2606                 return "$wgDBname-$wgDBprefix";
2607         } else {
2608                 return $wgDBname;
2609         }
2610 }
2611
2612 /**
2613  * Split a wiki ID into DB name and table prefix
2614  *
2615  * @param string $wiki
2616  *
2617  * @return array
2618  * @deprecated 1.32
2619  */
2620 function wfSplitWikiID( $wiki ) {
2621         $bits = explode( '-', $wiki, 2 );
2622         if ( count( $bits ) < 2 ) {
2623                 $bits[] = '';
2624         }
2625         return $bits;
2626 }
2627
2628 /**
2629  * Get a Database object.
2630  *
2631  * @param int $db Index of the connection to get. May be DB_MASTER for the
2632  *            master (for write queries), DB_REPLICA for potentially lagged read
2633  *            queries, or an integer >= 0 for a particular server.
2634  *
2635  * @param string|string[] $groups Query groups. An array of group names that this query
2636  *                belongs to. May contain a single string if the query is only
2637  *                in one group.
2638  *
2639  * @param string|bool $wiki The wiki ID, or false for the current wiki
2640  *
2641  * Note: multiple calls to wfGetDB(DB_REPLICA) during the course of one request
2642  * will always return the same object, unless the underlying connection or load
2643  * balancer is manually destroyed.
2644  *
2645  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
2646  * updater to ensure that a proper database is being updated.
2647  *
2648  * @todo Replace calls to wfGetDB with calls to LoadBalancer::getConnection()
2649  *       on an injected instance of LoadBalancer.
2650  *
2651  * @return \Wikimedia\Rdbms\Database
2652  */
2653 function wfGetDB( $db, $groups = [], $wiki = false ) {
2654         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
2655 }
2656
2657 /**
2658  * Get a load balancer object.
2659  *
2660  * @deprecated since 1.27, use MediaWikiServices::getDBLoadBalancer()
2661  *              or MediaWikiServices::getDBLoadBalancerFactory() instead.
2662  *
2663  * @param string|bool $wiki Wiki ID, or false for the current wiki
2664  * @return \Wikimedia\Rdbms\LoadBalancer
2665  */
2666 function wfGetLB( $wiki = false ) {
2667         if ( $wiki === false ) {
2668                 return MediaWikiServices::getInstance()->getDBLoadBalancer();
2669         } else {
2670                 $factory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
2671                 return $factory->getMainLB( $wiki );
2672         }
2673 }
2674
2675 /**
2676  * Get the load balancer factory object
2677  *
2678  * @deprecated since 1.27, use MediaWikiServices::getDBLoadBalancerFactory() instead.
2679  *
2680  * @return \Wikimedia\Rdbms\LBFactory
2681  */
2682 function wfGetLBFactory() {
2683         return MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
2684 }
2685
2686 /**
2687  * Find a file.
2688  * Shortcut for RepoGroup::singleton()->findFile()
2689  *
2690  * @param string|Title $title String or Title object
2691  * @param array $options Associative array of options (see RepoGroup::findFile)
2692  * @return File|bool File, or false if the file does not exist
2693  */
2694 function wfFindFile( $title, $options = [] ) {
2695         return RepoGroup::singleton()->findFile( $title, $options );
2696 }
2697
2698 /**
2699  * Get an object referring to a locally registered file.
2700  * Returns a valid placeholder object if the file does not exist.
2701  *
2702  * @param Title|string $title
2703  * @return LocalFile|null A File, or null if passed an invalid Title
2704  */
2705 function wfLocalFile( $title ) {
2706         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
2707 }
2708
2709 /**
2710  * Should low-performance queries be disabled?
2711  *
2712  * @return bool
2713  * @codeCoverageIgnore
2714  */
2715 function wfQueriesMustScale() {
2716         global $wgMiserMode;
2717         return $wgMiserMode
2718                 || ( SiteStats::pages() > 100000
2719                 && SiteStats::edits() > 1000000
2720                 && SiteStats::users() > 10000 );
2721 }
2722
2723 /**
2724  * Get the path to a specified script file, respecting file
2725  * extensions; this is a wrapper around $wgScriptPath etc.
2726  * except for 'index' and 'load' which use $wgScript/$wgLoadScript
2727  *
2728  * @param string $script Script filename, sans extension
2729  * @return string
2730  */
2731 function wfScript( $script = 'index' ) {
2732         global $wgScriptPath, $wgScript, $wgLoadScript;
2733         if ( $script === 'index' ) {
2734                 return $wgScript;
2735         } elseif ( $script === 'load' ) {
2736                 return $wgLoadScript;
2737         } else {
2738                 return "{$wgScriptPath}/{$script}.php";
2739         }
2740 }
2741
2742 /**
2743  * Get the script URL.
2744  *
2745  * @return string Script URL
2746  */
2747 function wfGetScriptUrl() {
2748         if ( isset( $_SERVER['SCRIPT_NAME'] ) ) {
2749                 /* as it was called, minus the query string.
2750                  *
2751                  * Some sites use Apache rewrite rules to handle subdomains,
2752                  * and have PHP set up in a weird way that causes PHP_SELF
2753                  * to contain the rewritten URL instead of the one that the
2754                  * outside world sees.
2755                  *
2756                  * If in this mode, use SCRIPT_URL instead, which mod_rewrite
2757                  * provides containing the "before" URL.
2758                  */
2759                 return $_SERVER['SCRIPT_NAME'];
2760         } else {
2761                 return $_SERVER['URL'];
2762         }
2763 }
2764
2765 /**
2766  * Convenience function converts boolean values into "true"
2767  * or "false" (string) values
2768  *
2769  * @param bool $value
2770  * @return string
2771  */
2772 function wfBoolToStr( $value ) {
2773         return $value ? 'true' : 'false';
2774 }
2775
2776 /**
2777  * Get a platform-independent path to the null file, e.g. /dev/null
2778  *
2779  * @return string
2780  */
2781 function wfGetNull() {
2782         return wfIsWindows() ? 'NUL' : '/dev/null';
2783 }
2784
2785 /**
2786  * Waits for the replica DBs to catch up to the master position
2787  *
2788  * Use this when updating very large numbers of rows, as in maintenance scripts,
2789  * to avoid causing too much lag. Of course, this is a no-op if there are no replica DBs.
2790  *
2791  * By default this waits on the main DB cluster of the current wiki.
2792  * If $cluster is set to "*" it will wait on all DB clusters, including
2793  * external ones. If the lag being waiting on is caused by the code that
2794  * does this check, it makes since to use $ifWritesSince, particularly if
2795  * cluster is "*", to avoid excess overhead.
2796  *
2797  * Never call this function after a big DB write that is still in a transaction.
2798  * This only makes sense after the possible lag inducing changes were committed.
2799  *
2800  * @param float|null $ifWritesSince Only wait if writes were done since this UNIX timestamp
2801  * @param string|bool $wiki Wiki identifier accepted by wfGetLB
2802  * @param string|bool $cluster Cluster name accepted by LBFactory. Default: false.
2803  * @param int|null $timeout Max wait time. Default: 60 seconds (cli), 1 second (web)
2804  * @return bool Success (able to connect and no timeouts reached)
2805  * @deprecated since 1.27 Use LBFactory::waitForReplication
2806  */
2807 function wfWaitForSlaves(
2808         $ifWritesSince = null, $wiki = false, $cluster = false, $timeout = null
2809 ) {
2810         $lbFactory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
2811
2812         if ( $cluster === '*' ) {
2813                 $cluster = false;
2814                 $domain = false;
2815         } elseif ( $wiki === false ) {
2816                 $domain = $lbFactory->getLocalDomainID();
2817         } else {
2818                 $domain = $wiki;
2819         }
2820
2821         $opts = [
2822                 'domain' => $domain,
2823                 'cluster' => $cluster,
2824                 // B/C: first argument used to be "max seconds of lag"; ignore such values
2825                 'ifWritesSince' => ( $ifWritesSince > 1e9 ) ? $ifWritesSince : null
2826         ];
2827         if ( $timeout !== null ) {
2828                 $opts['timeout'] = $timeout;
2829         }
2830
2831         return $lbFactory->waitForReplication( $opts );
2832 }
2833
2834 /**
2835  * Count down from $seconds to zero on the terminal, with a one-second pause
2836  * between showing each number. For use in command-line scripts.
2837  *
2838  * @deprecated since 1.31, use Maintenance::countDown()
2839  *
2840  * @codeCoverageIgnore
2841  * @param int $seconds
2842  */
2843 function wfCountDown( $seconds ) {
2844         wfDeprecated( __FUNCTION__, '1.31' );
2845         for ( $i = $seconds; $i >= 0; $i-- ) {
2846                 if ( $i != $seconds ) {
2847                         echo str_repeat( "\x08", strlen( $i + 1 ) );
2848                 }
2849                 echo $i;
2850                 flush();
2851                 if ( $i ) {
2852                         sleep( 1 );
2853                 }
2854         }
2855         echo "\n";
2856 }
2857
2858 /**
2859  * Replace all invalid characters with '-'.
2860  * Additional characters can be defined in $wgIllegalFileChars (see T22489).
2861  * By default, $wgIllegalFileChars includes ':', '/', '\'.
2862  *
2863  * @param string $name Filename to process
2864  * @return string
2865  */
2866 function wfStripIllegalFilenameChars( $name ) {
2867         global $wgIllegalFileChars;
2868         $illegalFileChars = $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '';
2869         $name = preg_replace(
2870                 "/[^" . Title::legalChars() . "]" . $illegalFileChars . "/",
2871                 '-',
2872                 $name
2873         );
2874         // $wgIllegalFileChars may not include '/' and '\', so we still need to do this
2875         $name = wfBaseName( $name );
2876         return $name;
2877 }
2878
2879 /**
2880  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit
2881  *
2882  * @return int Resulting value of the memory limit.
2883  */
2884 function wfMemoryLimit() {
2885         global $wgMemoryLimit;
2886         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
2887         if ( $memlimit != -1 ) {
2888                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
2889                 if ( $conflimit == -1 ) {
2890                         wfDebug( "Removing PHP's memory limit\n" );
2891                         Wikimedia\suppressWarnings();
2892                         ini_set( 'memory_limit', $conflimit );
2893                         Wikimedia\restoreWarnings();
2894                         return $conflimit;
2895                 } elseif ( $conflimit > $memlimit ) {
2896                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
2897                         Wikimedia\suppressWarnings();
2898                         ini_set( 'memory_limit', $conflimit );
2899                         Wikimedia\restoreWarnings();
2900                         return $conflimit;
2901                 }
2902         }
2903         return $memlimit;
2904 }
2905
2906 /**
2907  * Set PHP's time limit to the larger of php.ini or $wgTransactionalTimeLimit
2908  *
2909  * @return int Prior time limit
2910  * @since 1.26
2911  */
2912 function wfTransactionalTimeLimit() {
2913         global $wgTransactionalTimeLimit;
2914
2915         $timeLimit = ini_get( 'max_execution_time' );
2916         // Note that CLI scripts use 0
2917         if ( $timeLimit > 0 && $wgTransactionalTimeLimit > $timeLimit ) {
2918                 set_time_limit( $wgTransactionalTimeLimit );
2919         }
2920
2921         ignore_user_abort( true ); // ignore client disconnects
2922
2923         return $timeLimit;
2924 }
2925
2926 /**
2927  * Converts shorthand byte notation to integer form
2928  *
2929  * @param string $string
2930  * @param int $default Returned if $string is empty
2931  * @return int
2932  */
2933 function wfShorthandToInteger( $string = '', $default = -1 ) {
2934         $string = trim( $string );
2935         if ( $string === '' ) {
2936                 return $default;
2937         }
2938         $last = $string[strlen( $string ) - 1];
2939         $val = intval( $string );
2940         switch ( $last ) {
2941                 case 'g':
2942                 case 'G':
2943                         $val *= 1024;
2944                         // break intentionally missing
2945                 case 'm':
2946                 case 'M':
2947                         $val *= 1024;
2948                         // break intentionally missing
2949                 case 'k':
2950                 case 'K':
2951                         $val *= 1024;
2952         }
2953
2954         return $val;
2955 }
2956
2957 /**
2958  * Get the normalised IETF language tag
2959  * See unit test for examples.
2960  * See mediawiki.language.bcp47 for the JavaScript implementation.
2961  *
2962  * @deprecated since 1.31, use LanguageCode::bcp47() directly.
2963  *
2964  * @param string $code The language code.
2965  * @return string The language code which complying with BCP 47 standards.
2966  */
2967 function wfBCP47( $code ) {
2968         wfDeprecated( __METHOD__, '1.31' );
2969         return LanguageCode::bcp47( $code );
2970 }
2971
2972 /**
2973  * Get a specific cache object.
2974  *
2975  * @deprecated since 1.32, use ObjectCache::getInstance() instead
2976  * @param int|string $cacheType A CACHE_* constants, or other key in $wgObjectCaches
2977  * @return BagOStuff
2978  */
2979 function wfGetCache( $cacheType ) {
2980         return ObjectCache::getInstance( $cacheType );
2981 }
2982
2983 /**
2984  * Get the main cache object
2985  *
2986  * @deprecated since 1.32, use ObjectCache::getLocalClusterInstance() instead
2987  * @return BagOStuff
2988  */
2989 function wfGetMainCache() {
2990         return ObjectCache::getLocalClusterInstance();
2991 }
2992
2993 /**
2994  * Get the cache object used by the message cache
2995  *
2996  * @return BagOStuff
2997  */
2998 function wfGetMessageCacheStorage() {
2999         global $wgMessageCacheType;
3000         return ObjectCache::getInstance( $wgMessageCacheType );
3001 }
3002
3003 /**
3004  * Wrapper around php's unpack.
3005  *
3006  * @param string $format The format string (See php's docs)
3007  * @param string $data A binary string of binary data
3008  * @param int|bool $length The minimum length of $data or false. This is to
3009  *      prevent reading beyond the end of $data. false to disable the check.
3010  *
3011  * Also be careful when using this function to read unsigned 32 bit integer
3012  * because php might make it negative.
3013  *
3014  * @throws MWException If $data not long enough, or if unpack fails
3015  * @return array Associative array of the extracted data
3016  */
3017 function wfUnpack( $format, $data, $length = false ) {
3018         if ( $length !== false ) {
3019                 $realLen = strlen( $data );
3020                 if ( $realLen < $length ) {
3021                         throw new MWException( "Tried to use wfUnpack on a "
3022                                 . "string of length $realLen, but needed one "
3023                                 . "of at least length $length."
3024                         );
3025                 }
3026         }
3027
3028         Wikimedia\suppressWarnings();
3029         $result = unpack( $format, $data );
3030         Wikimedia\restoreWarnings();
3031
3032         if ( $result === false ) {
3033                 // If it cannot extract the packed data.
3034                 throw new MWException( "unpack could not unpack binary data" );
3035         }
3036         return $result;
3037 }
3038
3039 /**
3040  * Determine if an image exists on the 'bad image list'.
3041  *
3042  * The format of MediaWiki:Bad_image_list is as follows:
3043  *    * Only list items (lines starting with "*") are considered
3044  *    * The first link on a line must be a link to a bad image
3045  *    * Any subsequent links on the same line are considered to be exceptions,
3046  *      i.e. articles where the image may occur inline.
3047  *
3048  * @param string $name The image name to check
3049  * @param Title|bool $contextTitle The page on which the image occurs, if known
3050  * @param string|null $blacklist Wikitext of a file blacklist
3051  * @return bool
3052  */
3053 function wfIsBadImage( $name, $contextTitle = false, $blacklist = null ) {
3054         # Handle redirects; callers almost always hit wfFindFile() anyway,
3055         # so just use that method because it has a fast process cache.
3056         $file = wfFindFile( $name ); // get the final name
3057         $name = $file ? $file->getTitle()->getDBkey() : $name;
3058
3059         # Run the extension hook
3060         $bad = false;
3061         if ( !Hooks::run( 'BadImage', [ $name, &$bad ] ) ) {
3062                 return (bool)$bad;
3063         }
3064
3065         $cache = ObjectCache::getLocalServerInstance( 'hash' );
3066         $key = $cache->makeKey(
3067                 'bad-image-list', ( $blacklist === null ) ? 'default' : md5( $blacklist )
3068         );
3069         $badImages = $cache->get( $key );
3070
3071         if ( $badImages === false ) { // cache miss
3072                 if ( $blacklist === null ) {
3073                         $blacklist = wfMessage( 'bad_image_list' )->inContentLanguage()->plain(); // site list
3074                 }
3075                 # Build the list now
3076                 $badImages = [];
3077                 $lines = explode( "\n", $blacklist );
3078                 foreach ( $lines as $line ) {
3079                         # List items only
3080                         if ( substr( $line, 0, 1 ) !== '*' ) {
3081                                 continue;
3082                         }
3083
3084                         # Find all links
3085                         $m = [];
3086                         if ( !preg_match_all( '/\[\[:?(.*?)\]\]/', $line, $m ) ) {
3087                                 continue;
3088                         }
3089
3090                         $exceptions = [];
3091                         $imageDBkey = false;
3092                         foreach ( $m[1] as $i => $titleText ) {
3093                                 $title = Title::newFromText( $titleText );
3094                                 if ( !is_null( $title ) ) {
3095                                         if ( $i == 0 ) {
3096                                                 $imageDBkey = $title->getDBkey();
3097                                         } else {
3098                                                 $exceptions[$title->getPrefixedDBkey()] = true;
3099                                         }
3100                                 }
3101                         }
3102
3103                         if ( $imageDBkey !== false ) {
3104                                 $badImages[$imageDBkey] = $exceptions;
3105                         }
3106                 }
3107                 $cache->set( $key, $badImages, 60 );
3108         }
3109
3110         $contextKey = $contextTitle ? $contextTitle->getPrefixedDBkey() : false;
3111         $bad = isset( $badImages[$name] ) && !isset( $badImages[$name][$contextKey] );
3112
3113         return $bad;
3114 }
3115
3116 /**
3117  * Determine whether the client at a given source IP is likely to be able to
3118  * access the wiki via HTTPS.
3119  *
3120  * @param string $ip The IPv4/6 address in the normal human-readable form
3121  * @return bool
3122  */
3123 function wfCanIPUseHTTPS( $ip ) {
3124         $canDo = true;
3125         Hooks::run( 'CanIPUseHTTPS', [ $ip, &$canDo ] );
3126         return !!$canDo;
3127 }
3128
3129 /**
3130  * Determine input string is represents as infinity
3131  *
3132  * @param string $str The string to determine
3133  * @return bool
3134  * @since 1.25
3135  */
3136 function wfIsInfinity( $str ) {
3137         // These are hardcoded elsewhere in MediaWiki (e.g. mediawiki.special.block.js).
3138         $infinityValues = [ 'infinite', 'indefinite', 'infinity', 'never' ];
3139         return in_array( $str, $infinityValues );
3140 }
3141
3142 /**
3143  * Returns true if these thumbnail parameters match one that MediaWiki
3144  * requests from file description pages and/or parser output.
3145  *
3146  * $params is considered non-standard if they involve a non-standard
3147  * width or any non-default parameters aside from width and page number.
3148  * The number of possible files with standard parameters is far less than
3149  * that of all combinations; rate-limiting for them can thus be more generious.
3150  *
3151  * @param File $file
3152  * @param array $params
3153  * @return bool
3154  * @since 1.24 Moved from thumb.php to GlobalFunctions in 1.25
3155  */
3156 function wfThumbIsStandard( File $file, array $params ) {
3157         global $wgThumbLimits, $wgImageLimits, $wgResponsiveImages;
3158
3159         $multipliers = [ 1 ];
3160         if ( $wgResponsiveImages ) {
3161                 // These available sizes are hardcoded currently elsewhere in MediaWiki.
3162                 // @see Linker::processResponsiveImages
3163                 $multipliers[] = 1.5;
3164                 $multipliers[] = 2;
3165         }
3166
3167         $handler = $file->getHandler();
3168         if ( !$handler || !isset( $params['width'] ) ) {
3169                 return false;
3170         }
3171
3172         $basicParams = [];
3173         if ( isset( $params['page'] ) ) {
3174                 $basicParams['page'] = $params['page'];
3175         }
3176
3177         $thumbLimits = [];
3178         $imageLimits = [];
3179         // Expand limits to account for multipliers
3180         foreach ( $multipliers as $multiplier ) {
3181                 $thumbLimits = array_merge( $thumbLimits, array_map(
3182                         function ( $width ) use ( $multiplier ) {
3183                                 return round( $width * $multiplier );
3184                         }, $wgThumbLimits )
3185                 );
3186                 $imageLimits = array_merge( $imageLimits, array_map(
3187                         function ( $pair ) use ( $multiplier ) {
3188                                 return [
3189                                         round( $pair[0] * $multiplier ),
3190                                         round( $pair[1] * $multiplier ),
3191                                 ];
3192                         }, $wgImageLimits )
3193                 );
3194         }
3195
3196         // Check if the width matches one of $wgThumbLimits
3197         if ( in_array( $params['width'], $thumbLimits ) ) {
3198                 $normalParams = $basicParams + [ 'width' => $params['width'] ];
3199                 // Append any default values to the map (e.g. "lossy", "lossless", ...)
3200                 $handler->normaliseParams( $file, $normalParams );
3201         } else {
3202                 // If not, then check if the width matchs one of $wgImageLimits
3203                 $match = false;
3204                 foreach ( $imageLimits as $pair ) {
3205                         $normalParams = $basicParams + [ 'width' => $pair[0], 'height' => $pair[1] ];
3206                         // Decide whether the thumbnail should be scaled on width or height.
3207                         // Also append any default values to the map (e.g. "lossy", "lossless", ...)
3208                         $handler->normaliseParams( $file, $normalParams );
3209                         // Check if this standard thumbnail size maps to the given width
3210                         if ( $normalParams['width'] == $params['width'] ) {
3211                                 $match = true;
3212                                 break;
3213                         }
3214                 }
3215                 if ( !$match ) {
3216                         return false; // not standard for description pages
3217                 }
3218         }
3219
3220         // Check that the given values for non-page, non-width, params are just defaults
3221         foreach ( $params as $key => $value ) {
3222                 if ( !isset( $normalParams[$key] ) || $normalParams[$key] != $value ) {
3223                         return false;
3224                 }
3225         }
3226
3227         return true;
3228 }
3229
3230 /**
3231  * Merges two (possibly) 2 dimensional arrays into the target array ($baseArray).
3232  *
3233  * Values that exist in both values will be combined with += (all values of the array
3234  * of $newValues will be added to the values of the array of $baseArray, while values,
3235  * that exists in both, the value of $baseArray will be used).
3236  *
3237  * @param array $baseArray The array where you want to add the values of $newValues to
3238  * @param array $newValues An array with new values
3239  * @return array The combined array
3240  * @since 1.26
3241  */
3242 function wfArrayPlus2d( array $baseArray, array $newValues ) {
3243         // First merge items that are in both arrays
3244         foreach ( $baseArray as $name => &$groupVal ) {
3245                 if ( isset( $newValues[$name] ) ) {
3246                         $groupVal += $newValues[$name];
3247                 }
3248         }
3249         // Now add items that didn't exist yet
3250         $baseArray += $newValues;
3251
3252         return $baseArray;
3253 }
3254
3255 /**
3256  * Get system resource usage of current request context.
3257  * Invokes the getrusage(2) system call, requesting RUSAGE_SELF if on PHP5
3258  * or RUSAGE_THREAD if on HHVM. Returns false if getrusage is not available.
3259  *
3260  * @since 1.24
3261  * @return array|bool Resource usage data or false if no data available.
3262  */
3263 function wfGetRusage() {
3264         if ( !function_exists( 'getrusage' ) ) {
3265                 return false;
3266         } elseif ( defined( 'HHVM_VERSION' ) && PHP_OS === 'Linux' ) {
3267                 return getrusage( 2 /* RUSAGE_THREAD */ );
3268         } else {
3269                 return getrusage( 0 /* RUSAGE_SELF */ );
3270         }
3271 }