includes/GlobalFunctions.php

   1 <?php
   2 /**
   3  * Global functions used everywhere.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  */
  22
  23 if ( !defined( 'MEDIAWIKI' ) ) {
  24         die( "This file is part of MediaWiki, it is not a valid entry point" );
  25 }
  26
  27 use MediaWiki\Logger\LoggerFactory;
  28 use MediaWiki\ProcOpenError;
  29 use MediaWiki\Session\SessionManager;
  30 use MediaWiki\MediaWikiServices;
  31 use MediaWiki\Shell\Shell;
  32 use Wikimedia\ScopedCallback;
  33 use Wikimedia\Rdbms\DBReplicationWaitError;
  34 use Wikimedia\WrappedString;
  35
  36 /**
  37  * Load an extension
  38  *
  39  * This queues an extension to be loaded through
  40  * the ExtensionRegistry system.
  41  *
  42  * @param string $ext Name of the extension to load
  43  * @param string|null $path Absolute path of where to find the extension.json file
  44  * @since 1.25
  45  */
  46 function wfLoadExtension( $ext, $path = null ) {
  47         if ( !$path ) {
  48                 global $wgExtensionDirectory;
  49                 $path = "$wgExtensionDirectory/$ext/extension.json";
  50         }
  51         ExtensionRegistry::getInstance()->queue( $path );
  52 }
  53
  54 /**
  55  * Load multiple extensions at once
  56  *
  57  * Same as wfLoadExtension, but more efficient if you
  58  * are loading multiple extensions.
  59  *
  60  * If you want to specify custom paths, you should interact with
  61  * ExtensionRegistry directly.
  62  *
  63  * @see wfLoadExtension
  64  * @param string[] $exts Array of extension names to load
  65  * @since 1.25
  66  */
  67 function wfLoadExtensions( array $exts ) {
  68         global $wgExtensionDirectory;
  69         $registry = ExtensionRegistry::getInstance();
  70         foreach ( $exts as $ext ) {
  71                 $registry->queue( "$wgExtensionDirectory/$ext/extension.json" );
  72         }
  73 }
  74
  75 /**
  76  * Load a skin
  77  *
  78  * @see wfLoadExtension
  79  * @param string $skin Name of the extension to load
  80  * @param string|null $path Absolute path of where to find the skin.json file
  81  * @since 1.25
  82  */
  83 function wfLoadSkin( $skin, $path = null ) {
  84         if ( !$path ) {
  85                 global $wgStyleDirectory;
  86                 $path = "$wgStyleDirectory/$skin/skin.json";
  87         }
  88         ExtensionRegistry::getInstance()->queue( $path );
  89 }
  90
  91 /**
  92  * Load multiple skins at once
  93  *
  94  * @see wfLoadExtensions
  95  * @param string[] $skins Array of extension names to load
  96  * @since 1.25
  97  */
  98 function wfLoadSkins( array $skins ) {
  99         global $wgStyleDirectory;
 100         $registry = ExtensionRegistry::getInstance();
 101         foreach ( $skins as $skin ) {
 102                 $registry->queue( "$wgStyleDirectory/$skin/skin.json" );
 103         }
 104 }
 105
 106 /**
 107  * Like array_diff( $a, $b ) except that it works with two-dimensional arrays.
 108  * @param array $a
 109  * @param array $b
 110  * @return array
 111  */
 112 function wfArrayDiff2( $a, $b ) {
 113         return array_udiff( $a, $b, 'wfArrayDiff2_cmp' );
 114 }
 115
 116 /**
 117  * @param array|string $a
 118  * @param array|string $b
 119  * @return int
 120  */
 121 function wfArrayDiff2_cmp( $a, $b ) {
 122         if ( is_string( $a ) && is_string( $b ) ) {
 123                 return strcmp( $a, $b );
 124         } elseif ( count( $a ) !== count( $b ) ) {
 125                 return count( $a ) <=> count( $b );
 126         } else {
 127                 reset( $a );
 128                 reset( $b );
 129                 while ( key( $a ) !== null && key( $b ) !== null ) {
 130                         $valueA = current( $a );
 131                         $valueB = current( $b );
 132                         $cmp = strcmp( $valueA, $valueB );
 133                         if ( $cmp !== 0 ) {
 134                                 return $cmp;
 135                         }
 136                         next( $a );
 137                         next( $b );
 138                 }
 139                 return 0;
 140         }
 141 }
 142
 143 /**
 144  * Like array_filter with ARRAY_FILTER_USE_BOTH, but works pre-5.6.
 145  *
 146  * @param array $arr
 147  * @param callable $callback Will be called with the array value and key (in that order) and
 148  *   should return a bool which will determine whether the array element is kept.
 149  * @return array
 150  */
 151 function wfArrayFilter( array $arr, callable $callback ) {
 152         if ( defined( 'ARRAY_FILTER_USE_BOTH' ) ) {
 153                 return array_filter( $arr, $callback, ARRAY_FILTER_USE_BOTH );
 154         }
 155         $filteredKeys = array_filter( array_keys( $arr ), function ( $key ) use ( $arr, $callback ) {
 156                 return call_user_func( $callback, $arr[$key], $key );
 157         } );
 158         return array_intersect_key( $arr, array_fill_keys( $filteredKeys, true ) );
 159 }
 160
 161 /**
 162  * Like array_filter with ARRAY_FILTER_USE_KEY, but works pre-5.6.
 163  *
 164  * @param array $arr
 165  * @param callable $callback Will be called with the array key and should return a bool which
 166  *   will determine whether the array element is kept.
 167  * @return array
 168  */
 169 function wfArrayFilterByKey( array $arr, callable $callback ) {
 170         return wfArrayFilter( $arr, function ( $val, $key ) use ( $callback ) {
 171                 return call_user_func( $callback, $key );
 172         } );
 173 }
 174
 175 /**
 176  * Appends to second array if $value differs from that in $default
 177  *
 178  * @param string|int $key
 179  * @param mixed $value
 180  * @param mixed $default
 181  * @param array &$changed Array to alter
 182  * @throws MWException
 183  */
 184 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
 185         if ( is_null( $changed ) ) {
 186                 throw new MWException( 'GlobalFunctions::wfAppendToArrayIfNotDefault got null' );
 187         }
 188         if ( $default[$key] !== $value ) {
 189                 $changed[$key] = $value;
 190         }
 191 }
 192
 193 /**
 194  * Merge arrays in the style of getUserPermissionsErrors, with duplicate removal
 195  * e.g.
 196  *     wfMergeErrorArrays(
 197  *       [ [ 'x' ] ],
 198  *       [ [ 'x', '2' ] ],
 199  *       [ [ 'x' ] ],
 200  *       [ [ 'y' ] ]
 201  *     );
 202  * returns:
 203  *     [
 204  *       [ 'x', '2' ],
 205  *       [ 'x' ],
 206  *       [ 'y' ]
 207  *     ]
 208  *
 209  * @param array $array1,...
 210  * @return array
 211  */
 212 function wfMergeErrorArrays( /*...*/ ) {
 213         $args = func_get_args();
 214         $out = [];
 215         foreach ( $args as $errors ) {
 216                 foreach ( $errors as $params ) {
 217                         $originalParams = $params;
 218                         if ( $params[0] instanceof MessageSpecifier ) {
 219                                 $msg = $params[0];
 220                                 $params = array_merge( [ $msg->getKey() ], $msg->getParams() );
 221                         }
 222                         # @todo FIXME: Sometimes get nested arrays for $params,
 223                         # which leads to E_NOTICEs
 224                         $spec = implode( "\t", $params );
 225                         $out[$spec] = $originalParams;
 226                 }
 227         }
 228         return array_values( $out );
 229 }
 230
 231 /**
 232  * Insert array into another array after the specified *KEY*
 233  *
 234  * @param array $array The array.
 235  * @param array $insert The array to insert.
 236  * @param mixed $after The key to insert after
 237  * @return array
 238  */
 239 function wfArrayInsertAfter( array $array, array $insert, $after ) {
 240         // Find the offset of the element to insert after.
 241         $keys = array_keys( $array );
 242         $offsetByKey = array_flip( $keys );
 243
 244         $offset = $offsetByKey[$after];
 245
 246         // Insert at the specified offset
 247         $before = array_slice( $array, 0, $offset + 1, true );
 248         $after = array_slice( $array, $offset + 1, count( $array ) - $offset, true );
 249
 250         $output = $before + $insert + $after;
 251
 252         return $output;
 253 }
 254
 255 /**
 256  * Recursively converts the parameter (an object) to an array with the same data
 257  *
 258  * @param object|array $objOrArray
 259  * @param bool $recursive
 260  * @return array
 261  */
 262 function wfObjectToArray( $objOrArray, $recursive = true ) {
 263         $array = [];
 264         if ( is_object( $objOrArray ) ) {
 265                 $objOrArray = get_object_vars( $objOrArray );
 266         }
 267         foreach ( $objOrArray as $key => $value ) {
 268                 if ( $recursive && ( is_object( $value ) || is_array( $value ) ) ) {
 269                         $value = wfObjectToArray( $value );
 270                 }
 271
 272                 $array[$key] = $value;
 273         }
 274
 275         return $array;
 276 }
 277
 278 /**
 279  * Get a random decimal value between 0 and 1, in a way
 280  * not likely to give duplicate values for any realistic
 281  * number of articles.
 282  *
 283  * @note This is designed for use in relation to Special:RandomPage
 284  *       and the page_random database field.
 285  *
 286  * @return string
 287  */
 288 function wfRandom() {
 289         // The maximum random value is "only" 2^31-1, so get two random
 290         // values to reduce the chance of dupes
 291         $max = mt_getrandmax() + 1;
 292         $rand = number_format( ( mt_rand() * $max + mt_rand() ) / $max / $max, 12, '.', '' );
 293         return $rand;
 294 }
 295
 296 /**
 297  * Get a random string containing a number of pseudo-random hex characters.
 298  *
 299  * @note This is not secure, if you are trying to generate some sort
 300  *       of token please use MWCryptRand instead.
 301  *
 302  * @param int $length The length of the string to generate
 303  * @return string
 304  * @since 1.20
 305  */
 306 function wfRandomString( $length = 32 ) {
 307         $str = '';
 308         for ( $n = 0; $n < $length; $n += 7 ) {
 309                 $str .= sprintf( '%07x', mt_rand() & 0xfffffff );
 310         }
 311         return substr( $str, 0, $length );
 312 }
 313
 314 /**
 315  * We want some things to be included as literal characters in our title URLs
 316  * for prettiness, which urlencode encodes by default.  According to RFC 1738,
 317  * all of the following should be safe:
 318  *
 319  * ;:@&=$-_.+!*'(),
 320  *
 321  * RFC 1738 says ~ is unsafe, however RFC 3986 considers it an unreserved
 322  * character which should not be encoded. More importantly, google chrome
 323  * always converts %7E back to ~, and converting it in this function can
 324  * cause a redirect loop (T105265).
 325  *
 326  * But + is not safe because it's used to indicate a space; &= are only safe in
 327  * paths and not in queries (and we don't distinguish here); ' seems kind of
 328  * scary; and urlencode() doesn't touch -_. to begin with.  Plus, although /
 329  * is reserved, we don't care.  So the list we unescape is:
 330  *
 331  * ;:@$!*(),/~
 332  *
 333  * However, IIS7 redirects fail when the url contains a colon (see T24709),
 334  * so no fancy : for IIS7.
 335  *
 336  * %2F in the page titles seems to fatally break for some reason.
 337  *
 338  * @param string $s
 339  * @return string
 340  */
 341 function wfUrlencode( $s ) {
 342         static $needle;
 343
 344         if ( is_null( $s ) ) {
 345                 $needle = null;
 346                 return '';
 347         }
 348
 349         if ( is_null( $needle ) ) {
 350                 $needle = [ '%3B', '%40', '%24', '%21', '%2A', '%28', '%29', '%2C', '%2F', '%7E' ];
 351                 if ( !isset( $_SERVER['SERVER_SOFTWARE'] ) ||
 352                         ( strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/7' ) === false )
 353                 ) {
 354                         $needle[] = '%3A';
 355                 }
 356         }
 357
 358         $s = urlencode( $s );
 359         $s = str_ireplace(
 360                 $needle,
 361                 [ ';', '@', '$', '!', '*', '(', ')', ',', '/', '~', ':' ],
 362                 $s
 363         );
 364
 365         return $s;
 366 }
 367
 368 /**
 369  * This function takes one or two arrays as input, and returns a CGI-style string, e.g.
 370  * "days=7&limit=100". Options in the first array override options in the second.
 371  * Options set to null or false will not be output.
 372  *
 373  * @param array $array1 ( String|Array )
 374  * @param array|null $array2 ( String|Array )
 375  * @param string $prefix
 376  * @return string
 377  */
 378 function wfArrayToCgi( $array1, $array2 = null, $prefix = '' ) {
 379         if ( !is_null( $array2 ) ) {
 380                 $array1 = $array1 + $array2;
 381         }
 382
 383         $cgi = '';
 384         foreach ( $array1 as $key => $value ) {
 385                 if ( !is_null( $value ) && $value !== false ) {
 386                         if ( $cgi != '' ) {
 387                                 $cgi .= '&';
 388                         }
 389                         if ( $prefix !== '' ) {
 390                                 $key = $prefix . "[$key]";
 391                         }
 392                         if ( is_array( $value ) ) {
 393                                 $firstTime = true;
 394                                 foreach ( $value as $k => $v ) {
 395                                         $cgi .= $firstTime ? '' : '&';
 396                                         if ( is_array( $v ) ) {
 397                                                 $cgi .= wfArrayToCgi( $v, null, $key . "[$k]" );
 398                                         } else {
 399                                                 $cgi .= urlencode( $key . "[$k]" ) . '=' . urlencode( $v );
 400                                         }
 401                                         $firstTime = false;
 402                                 }
 403                         } else {
 404                                 if ( is_object( $value ) ) {
 405                                         $value = $value->__toString();
 406                                 }
 407                                 $cgi .= urlencode( $key ) . '=' . urlencode( $value );
 408                         }
 409                 }
 410         }
 411         return $cgi;
 412 }
 413
 414 /**
 415  * This is the logical opposite of wfArrayToCgi(): it accepts a query string as
 416  * its argument and returns the same string in array form.  This allows compatibility
 417  * with legacy functions that accept raw query strings instead of nice
 418  * arrays.  Of course, keys and values are urldecode()d.
 419  *
 420  * @param string $query Query string
 421  * @return string[] Array version of input
 422  */
 423 function wfCgiToArray( $query ) {
 424         if ( isset( $query[0] ) && $query[0] == '?' ) {
 425                 $query = substr( $query, 1 );
 426         }
 427         $bits = explode( '&', $query );
 428         $ret = [];
 429         foreach ( $bits as $bit ) {
 430                 if ( $bit === '' ) {
 431                         continue;
 432                 }
 433                 if ( strpos( $bit, '=' ) === false ) {
 434                         // Pieces like &qwerty become 'qwerty' => '' (at least this is what php does)
 435                         $key = $bit;
 436                         $value = '';
 437                 } else {
 438                         list( $key, $value ) = explode( '=', $bit );
 439                 }
 440                 $key = urldecode( $key );
 441                 $value = urldecode( $value );
 442                 if ( strpos( $key, '[' ) !== false ) {
 443                         $keys = array_reverse( explode( '[', $key ) );
 444                         $key = array_pop( $keys );
 445                         $temp = $value;
 446                         foreach ( $keys as $k ) {
 447                                 $k = substr( $k, 0, -1 );
 448                                 $temp = [ $k => $temp ];
 449                         }
 450                         if ( isset( $ret[$key] ) ) {
 451                                 $ret[$key] = array_merge( $ret[$key], $temp );
 452                         } else {
 453                                 $ret[$key] = $temp;
 454                         }
 455                 } else {
 456                         $ret[$key] = $value;
 457                 }
 458         }
 459         return $ret;
 460 }
 461
 462 /**
 463  * Append a query string to an existing URL, which may or may not already
 464  * have query string parameters already. If so, they will be combined.
 465  *
 466  * @param string $url
 467  * @param string|string[] $query String or associative array
 468  * @return string
 469  */
 470 function wfAppendQuery( $url, $query ) {
 471         if ( is_array( $query ) ) {
 472                 $query = wfArrayToCgi( $query );
 473         }
 474         if ( $query != '' ) {
 475                 // Remove the fragment, if there is one
 476                 $fragment = false;
 477                 $hashPos = strpos( $url, '#' );
 478                 if ( $hashPos !== false ) {
 479                         $fragment = substr( $url, $hashPos );
 480                         $url = substr( $url, 0, $hashPos );
 481                 }
 482
 483                 // Add parameter
 484                 if ( false === strpos( $url, '?' ) ) {
 485                         $url .= '?';
 486                 } else {
 487                         $url .= '&';
 488                 }
 489                 $url .= $query;
 490
 491                 // Put the fragment back
 492                 if ( $fragment !== false ) {
 493                         $url .= $fragment;
 494                 }
 495         }
 496         return $url;
 497 }
 498
 499 /**
 500  * Expand a potentially local URL to a fully-qualified URL. Assumes $wgServer
 501  * is correct.
 502  *
 503  * The meaning of the PROTO_* constants is as follows:
 504  * PROTO_HTTP: Output a URL starting with http://
 505  * PROTO_HTTPS: Output a URL starting with https://
 506  * PROTO_RELATIVE: Output a URL starting with // (protocol-relative URL)
 507  * PROTO_CURRENT: Output a URL starting with either http:// or https:// , depending
 508  *    on which protocol was used for the current incoming request
 509  * PROTO_CANONICAL: For URLs without a domain, like /w/index.php , use $wgCanonicalServer.
 510  *    For protocol-relative URLs, use the protocol of $wgCanonicalServer
 511  * PROTO_INTERNAL: Like PROTO_CANONICAL, but uses $wgInternalServer instead of $wgCanonicalServer
 512  *
 513  * @todo this won't work with current-path-relative URLs
 514  * like "subdir/foo.html", etc.
 515  *
 516  * @param string $url Either fully-qualified or a local path + query
 517  * @param string|int|null $defaultProto One of the PROTO_* constants. Determines the
 518  *    protocol to use if $url or $wgServer is protocol-relative
 519  * @return string|false Fully-qualified URL, current-path-relative URL or false if
 520  *    no valid URL can be constructed
 521  */
 522 function wfExpandUrl( $url, $defaultProto = PROTO_CURRENT ) {
 523         global $wgServer, $wgCanonicalServer, $wgInternalServer, $wgRequest,
 524                 $wgHttpsPort;
 525         if ( $defaultProto === PROTO_CANONICAL ) {
 526                 $serverUrl = $wgCanonicalServer;
 527         } elseif ( $defaultProto === PROTO_INTERNAL && $wgInternalServer !== false ) {
 528                 // Make $wgInternalServer fall back to $wgServer if not set
 529                 $serverUrl = $wgInternalServer;
 530         } else {
 531                 $serverUrl = $wgServer;
 532                 if ( $defaultProto === PROTO_CURRENT ) {
 533                         $defaultProto = $wgRequest->getProtocol() . '://';
 534                 }
 535         }
 536
 537         // Analyze $serverUrl to obtain its protocol
 538         $bits = wfParseUrl( $serverUrl );
 539         $serverHasProto = $bits && $bits['scheme'] != '';
 540
 541         if ( $defaultProto === PROTO_CANONICAL || $defaultProto === PROTO_INTERNAL ) {
 542                 if ( $serverHasProto ) {
 543                         $defaultProto = $bits['scheme'] . '://';
 544                 } else {
 545                         // $wgCanonicalServer or $wgInternalServer doesn't have a protocol.
 546                         // This really isn't supposed to happen. Fall back to HTTP in this
 547                         // ridiculous case.
 548                         $defaultProto = PROTO_HTTP;
 549                 }
 550         }
 551
 552         $defaultProtoWithoutSlashes = substr( $defaultProto, 0, -2 );
 553
 554         if ( substr( $url, 0, 2 ) == '//' ) {
 555                 $url = $defaultProtoWithoutSlashes . $url;
 556         } elseif ( substr( $url, 0, 1 ) == '/' ) {
 557                 // If $serverUrl is protocol-relative, prepend $defaultProtoWithoutSlashes,
 558                 // otherwise leave it alone.
 559                 $url = ( $serverHasProto ? '' : $defaultProtoWithoutSlashes ) . $serverUrl . $url;
 560         }
 561
 562         $bits = wfParseUrl( $url );
 563
 564         // ensure proper port for HTTPS arrives in URL
 565         // https://phabricator.wikimedia.org/T67184
 566         if ( $defaultProto === PROTO_HTTPS && $wgHttpsPort != 443 ) {
 567                 $bits['port'] = $wgHttpsPort;
 568         }
 569
 570         if ( $bits && isset( $bits['path'] ) ) {
 571                 $bits['path'] = wfRemoveDotSegments( $bits['path'] );
 572                 return wfAssembleUrl( $bits );
 573         } elseif ( $bits ) {
 574                 # No path to expand
 575                 return $url;
 576         } elseif ( substr( $url, 0, 1 ) != '/' ) {
 577                 # URL is a relative path
 578                 return wfRemoveDotSegments( $url );
 579         }
 580
 581         # Expanded URL is not valid.
 582         return false;
 583 }
 584
 585 /**
 586  * This function will reassemble a URL parsed with wfParseURL.  This is useful
 587  * if you need to edit part of a URL and put it back together.
 588  *
 589  * This is the basic structure used (brackets contain keys for $urlParts):
 590  * [scheme][delimiter][user]:[pass]@[host]:[port][path]?[query]#[fragment]
 591  *
 592  * @todo Need to integrate this into wfExpandUrl (see T34168)
 593  *
 594  * @since 1.19
 595  * @param array $urlParts URL parts, as output from wfParseUrl
 596  * @return string URL assembled from its component parts
 597  */
 598 function wfAssembleUrl( $urlParts ) {
 599         $result = '';
 600
 601         if ( isset( $urlParts['delimiter'] ) ) {
 602                 if ( isset( $urlParts['scheme'] ) ) {
 603                         $result .= $urlParts['scheme'];
 604                 }
 605
 606                 $result .= $urlParts['delimiter'];
 607         }
 608
 609         if ( isset( $urlParts['host'] ) ) {
 610                 if ( isset( $urlParts['user'] ) ) {
 611                         $result .= $urlParts['user'];
 612                         if ( isset( $urlParts['pass'] ) ) {
 613                                 $result .= ':' . $urlParts['pass'];
 614                         }
 615                         $result .= '@';
 616                 }
 617
 618                 $result .= $urlParts['host'];
 619
 620                 if ( isset( $urlParts['port'] ) ) {
 621                         $result .= ':' . $urlParts['port'];
 622                 }
 623         }
 624
 625         if ( isset( $urlParts['path'] ) ) {
 626                 $result .= $urlParts['path'];
 627         }
 628
 629         if ( isset( $urlParts['query'] ) ) {
 630                 $result .= '?' . $urlParts['query'];
 631         }
 632
 633         if ( isset( $urlParts['fragment'] ) ) {
 634                 $result .= '#' . $urlParts['fragment'];
 635         }
 636
 637         return $result;
 638 }
 639
 640 /**
 641  * Remove all dot-segments in the provided URL path.  For example,
 642  * '/a/./b/../c/' becomes '/a/c/'.  For details on the algorithm, please see
 643  * RFC3986 section 5.2.4.
 644  *
 645  * @todo Need to integrate this into wfExpandUrl (see T34168)
 646  *
 647  * @since 1.19
 648  *
 649  * @param string $urlPath URL path, potentially containing dot-segments
 650  * @return string URL path with all dot-segments removed
 651  */
 652 function wfRemoveDotSegments( $urlPath ) {
 653         $output = '';
 654         $inputOffset = 0;
 655         $inputLength = strlen( $urlPath );
 656
 657         while ( $inputOffset < $inputLength ) {
 658                 $prefixLengthOne = substr( $urlPath, $inputOffset, 1 );
 659                 $prefixLengthTwo = substr( $urlPath, $inputOffset, 2 );
 660                 $prefixLengthThree = substr( $urlPath, $inputOffset, 3 );
 661                 $prefixLengthFour = substr( $urlPath, $inputOffset, 4 );
 662                 $trimOutput = false;
 663
 664                 if ( $prefixLengthTwo == './' ) {
 665                         # Step A, remove leading "./"
 666                         $inputOffset += 2;
 667                 } elseif ( $prefixLengthThree == '../' ) {
 668                         # Step A, remove leading "../"
 669                         $inputOffset += 3;
 670                 } elseif ( ( $prefixLengthTwo == '/.' ) && ( $inputOffset + 2 == $inputLength ) ) {
 671                         # Step B, replace leading "/.$" with "/"
 672                         $inputOffset += 1;
 673                         $urlPath[$inputOffset] = '/';
 674                 } elseif ( $prefixLengthThree == '/./' ) {
 675                         # Step B, replace leading "/./" with "/"
 676                         $inputOffset += 2;
 677                 } elseif ( $prefixLengthThree == '/..' && ( $inputOffset + 3 == $inputLength ) ) {
 678                         # Step C, replace leading "/..$" with "/" and
 679                         # remove last path component in output
 680                         $inputOffset += 2;
 681                         $urlPath[$inputOffset] = '/';
 682                         $trimOutput = true;
 683                 } elseif ( $prefixLengthFour == '/../' ) {
 684                         # Step C, replace leading "/../" with "/" and
 685                         # remove last path component in output
 686                         $inputOffset += 3;
 687                         $trimOutput = true;
 688                 } elseif ( ( $prefixLengthOne == '.' ) && ( $inputOffset + 1 == $inputLength ) ) {
 689                         # Step D, remove "^.$"
 690                         $inputOffset += 1;
 691                 } elseif ( ( $prefixLengthTwo == '..' ) && ( $inputOffset + 2 == $inputLength ) ) {
 692                         # Step D, remove "^..$"
 693                         $inputOffset += 2;
 694                 } else {
 695                         # Step E, move leading path segment to output
 696                         if ( $prefixLengthOne == '/' ) {
 697                                 $slashPos = strpos( $urlPath, '/', $inputOffset + 1 );
 698                         } else {
 699                                 $slashPos = strpos( $urlPath, '/', $inputOffset );
 700                         }
 701                         if ( $slashPos === false ) {
 702                                 $output .= substr( $urlPath, $inputOffset );
 703                                 $inputOffset = $inputLength;
 704                         } else {
 705                                 $output .= substr( $urlPath, $inputOffset, $slashPos - $inputOffset );
 706                                 $inputOffset += $slashPos - $inputOffset;
 707                         }
 708                 }
 709
 710                 if ( $trimOutput ) {
 711                         $slashPos = strrpos( $output, '/' );
 712                         if ( $slashPos === false ) {
 713                                 $output = '';
 714                         } else {
 715                                 $output = substr( $output, 0, $slashPos );
 716                         }
 717                 }
 718         }
 719
 720         return $output;
 721 }
 722
 723 /**
 724  * Returns a regular expression of url protocols
 725  *
 726  * @param bool $includeProtocolRelative If false, remove '//' from the returned protocol list.
 727  *        DO NOT USE this directly, use wfUrlProtocolsWithoutProtRel() instead
 728  * @return string
 729  */
 730 function wfUrlProtocols( $includeProtocolRelative = true ) {
 731         global $wgUrlProtocols;
 732
 733         // Cache return values separately based on $includeProtocolRelative
 734         static $withProtRel = null, $withoutProtRel = null;
 735         $cachedValue = $includeProtocolRelative ? $withProtRel : $withoutProtRel;
 736         if ( !is_null( $cachedValue ) ) {
 737                 return $cachedValue;
 738         }
 739
 740         // Support old-style $wgUrlProtocols strings, for backwards compatibility
 741         // with LocalSettings files from 1.5
 742         if ( is_array( $wgUrlProtocols ) ) {
 743                 $protocols = [];
 744                 foreach ( $wgUrlProtocols as $protocol ) {
 745                         // Filter out '//' if !$includeProtocolRelative
 746                         if ( $includeProtocolRelative || $protocol !== '//' ) {
 747                                 $protocols[] = preg_quote( $protocol, '/' );
 748                         }
 749                 }
 750
 751                 $retval = implode( '|', $protocols );
 752         } else {
 753                 // Ignore $includeProtocolRelative in this case
 754                 // This case exists for pre-1.6 compatibility, and we can safely assume
 755                 // that '//' won't appear in a pre-1.6 config because protocol-relative
 756                 // URLs weren't supported until 1.18
 757                 $retval = $wgUrlProtocols;
 758         }
 759
 760         // Cache return value
 761         if ( $includeProtocolRelative ) {
 762                 $withProtRel = $retval;
 763         } else {
 764                 $withoutProtRel = $retval;
 765         }
 766         return $retval;
 767 }
 768
 769 /**
 770  * Like wfUrlProtocols(), but excludes '//' from the protocol list. Use this if
 771  * you need a regex that matches all URL protocols but does not match protocol-
 772  * relative URLs
 773  * @return string
 774  */
 775 function wfUrlProtocolsWithoutProtRel() {
 776         return wfUrlProtocols( false );
 777 }
 778
 779 /**
 780  * parse_url() work-alike, but non-broken.  Differences:
 781  *
 782  * 1) Does not raise warnings on bad URLs (just returns false).
 783  * 2) Handles protocols that don't use :// (e.g., mailto: and news:, as well as
 784  *    protocol-relative URLs) correctly.
 785  * 3) Adds a "delimiter" element to the array (see (2)).
 786  * 4) Verifies that the protocol is on the $wgUrlProtocols whitelist.
 787  * 5) Rejects some invalid URLs that parse_url doesn't, e.g. the empty string or URLs starting with
 788  *    a line feed character.
 789  *
 790  * @param string $url A URL to parse
 791  * @return string[]|bool Bits of the URL in an associative array, or false on failure.
 792  *   Possible fields:
 793  *   - scheme: URI scheme (protocol), e.g. 'http', 'mailto'. Lowercase, always present, but can
 794  *       be an empty string for protocol-relative URLs.
 795  *   - delimiter: either '://', ':' or '//'. Always present.
 796  *   - host: domain name / IP. Always present, but could be an empty string, e.g. for file: URLs.
 797  *   - user: user name, e.g. for HTTP Basic auth URLs such as http://user:pass@example.com/
 798  *       Missing when there is no username.
 799  *   - pass: password, same as above.
 800  *   - path: path including the leading /. Will be missing when empty (e.g. 'http://example.com')
 801  *   - query: query string (as a string; see wfCgiToArray() for parsing it), can be missing.
 802  *   - fragment: the part after #, can be missing.
 803  */
 804 function wfParseUrl( $url ) {
 805         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
 806
 807         // Protocol-relative URLs are handled really badly by parse_url(). It's so
 808         // bad that the easiest way to handle them is to just prepend 'http:' and
 809         // strip the protocol out later.
 810         $wasRelative = substr( $url, 0, 2 ) == '//';
 811         if ( $wasRelative ) {
 812                 $url = "http:$url";
 813         }
 814         Wikimedia\suppressWarnings();
 815         $bits = parse_url( $url );
 816         Wikimedia\restoreWarnings();
 817         // parse_url() returns an array without scheme for some invalid URLs, e.g.
 818         // parse_url("%0Ahttp://example.com") == [ 'host' => '%0Ahttp', 'path' => 'example.com' ]
 819         if ( !$bits || !isset( $bits['scheme'] ) ) {
 820                 return false;
 821         }
 822
 823         // parse_url() incorrectly handles schemes case-sensitively. Convert it to lowercase.
 824         $bits['scheme'] = strtolower( $bits['scheme'] );
 825
 826         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
 827         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
 828                 $bits['delimiter'] = '://';
 829         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
 830                 $bits['delimiter'] = ':';
 831                 // parse_url detects for news: and mailto: the host part of an url as path
 832                 // We have to correct this wrong detection
 833                 if ( isset( $bits['path'] ) ) {
 834                         $bits['host'] = $bits['path'];
 835                         $bits['path'] = '';
 836                 }
 837         } else {
 838                 return false;
 839         }
 840
 841         /* Provide an empty host for eg. file:/// urls (see T30627) */
 842         if ( !isset( $bits['host'] ) ) {
 843                 $bits['host'] = '';
 844
 845                 // See T47069
 846                 if ( isset( $bits['path'] ) ) {
 847                         /* parse_url loses the third / for file:///c:/ urls (but not on variants) */
 848                         if ( substr( $bits['path'], 0, 1 ) !== '/' ) {
 849                                 $bits['path'] = '/' . $bits['path'];
 850                         }
 851                 } else {
 852                         $bits['path'] = '';
 853                 }
 854         }
 855
 856         // If the URL was protocol-relative, fix scheme and delimiter
 857         if ( $wasRelative ) {
 858                 $bits['scheme'] = '';
 859                 $bits['delimiter'] = '//';
 860         }
 861         return $bits;
 862 }
 863
 864 /**
 865  * Take a URL, make sure it's expanded to fully qualified, and replace any
 866  * encoded non-ASCII Unicode characters with their UTF-8 original forms
 867  * for more compact display and legibility for local audiences.
 868  *
 869  * @todo handle punycode domains too
 870  *
 871  * @param string $url
 872  * @return string
 873  */
 874 function wfExpandIRI( $url ) {
 875         return preg_replace_callback(
 876                 '/((?:%[89A-F][0-9A-F])+)/i',
 877                 'wfExpandIRI_callback',
 878                 wfExpandUrl( $url )
 879         );
 880 }
 881
 882 /**
 883  * Private callback for wfExpandIRI
 884  * @param array $matches
 885  * @return string
 886  */
 887 function wfExpandIRI_callback( $matches ) {
 888         return urldecode( $matches[1] );
 889 }
 890
 891 /**
 892  * Make URL indexes, appropriate for the el_index field of externallinks.
 893  *
 894  * @param string $url
 895  * @return array
 896  */
 897 function wfMakeUrlIndexes( $url ) {
 898         $bits = wfParseUrl( $url );
 899
 900         // Reverse the labels in the hostname, convert to lower case
 901         // For emails reverse domainpart only
 902         if ( $bits['scheme'] == 'mailto' ) {
 903                 $mailparts = explode( '@', $bits['host'], 2 );
 904                 if ( count( $mailparts ) === 2 ) {
 905                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
 906                 } else {
 907                         // No domain specified, don't mangle it
 908                         $domainpart = '';
 909                 }
 910                 $reversedHost = $domainpart . '@' . $mailparts[0];
 911         } else {
 912                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
 913         }
 914         // Add an extra dot to the end
 915         // Why? Is it in wrong place in mailto links?
 916         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
 917                 $reversedHost .= '.';
 918         }
 919         // Reconstruct the pseudo-URL
 920         $prot = $bits['scheme'];
 921         $index = $prot . $bits['delimiter'] . $reversedHost;
 922         // Leave out user and password. Add the port, path, query and fragment
 923         if ( isset( $bits['port'] ) ) {
 924                 $index .= ':' . $bits['port'];
 925         }
 926         if ( isset( $bits['path'] ) ) {
 927                 $index .= $bits['path'];
 928         } else {
 929                 $index .= '/';
 930         }
 931         if ( isset( $bits['query'] ) ) {
 932                 $index .= '?' . $bits['query'];
 933         }
 934         if ( isset( $bits['fragment'] ) ) {
 935                 $index .= '#' . $bits['fragment'];
 936         }
 937
 938         if ( $prot == '' ) {
 939                 return [ "http:$index", "https:$index" ];
 940         } else {
 941                 return [ $index ];
 942         }
 943 }
 944
 945 /**
 946  * Check whether a given URL has a domain that occurs in a given set of domains
 947  * @param string $url
 948  * @param array $domains Array of domains (strings)
 949  * @return bool True if the host part of $url ends in one of the strings in $domains
 950  */
 951 function wfMatchesDomainList( $url, $domains ) {
 952         $bits = wfParseUrl( $url );
 953         if ( is_array( $bits ) && isset( $bits['host'] ) ) {
 954                 $host = '.' . $bits['host'];
 955                 foreach ( (array)$domains as $domain ) {
 956                         $domain = '.' . $domain;
 957                         if ( substr( $host, -strlen( $domain ) ) === $domain ) {
 958                                 return true;
 959                         }
 960                 }
 961         }
 962         return false;
 963 }
 964
 965 /**
 966  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
 967  * In normal operation this is a NOP.
 968  *
 969  * Controlling globals:
 970  * $wgDebugLogFile - points to the log file
 971  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
 972  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
 973  *
 974  * @since 1.25 support for additional context data
 975  *
 976  * @param string $text
 977  * @param string|bool $dest Destination of the message:
 978  *     - 'all': both to the log and HTML (debug toolbar or HTML comments)
 979  *     - 'private': excluded from HTML output
 980  *   For backward compatibility, it can also take a boolean:
 981  *     - true: same as 'all'
 982  *     - false: same as 'private'
 983  * @param array $context Additional logging context data
 984  */
 985 function wfDebug( $text, $dest = 'all', array $context = [] ) {
 986         global $wgDebugRawPage, $wgDebugLogPrefix;
 987         global $wgDebugTimestamps;
 988
 989         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
 990                 return;
 991         }
 992
 993         $text = trim( $text );
 994
 995         if ( $wgDebugTimestamps ) {
 996                 $context['seconds_elapsed'] = sprintf(
 997                         '%6.4f',
 998                         microtime( true ) - $_SERVER['REQUEST_TIME_FLOAT']
 999                 );
1000                 $context['memory_used'] = sprintf(
1001                         '%5.1fM',
1002                         ( memory_get_usage( true ) / ( 1024 * 1024 ) )
1003                 );
1004         }
1005
1006         if ( $wgDebugLogPrefix !== '' ) {
1007                 $context['prefix'] = $wgDebugLogPrefix;
1008         }
1009         $context['private'] = ( $dest === false || $dest === 'private' );
1010
1011         $logger = LoggerFactory::getInstance( 'wfDebug' );
1012         $logger->debug( $text, $context );
1013 }
1014
1015 /**
1016  * Returns true if debug logging should be suppressed if $wgDebugRawPage = false
1017  * @return bool
1018  */
1019 function wfIsDebugRawPage() {
1020         static $cache;
1021         if ( $cache !== null ) {
1022                 return $cache;
1023         }
1024         // Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
1025         // phpcs:ignore MediaWiki.Usage.SuperGlobalsUsage.SuperGlobals
1026         if ( ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' )
1027                 || (
1028                         isset( $_SERVER['SCRIPT_NAME'] )
1029                         && substr( $_SERVER['SCRIPT_NAME'], -8 ) == 'load.php'
1030                 )
1031         ) {
1032                 $cache = true;
1033         } else {
1034                 $cache = false;
1035         }
1036         return $cache;
1037 }
1038
1039 /**
1040  * Send a line giving PHP memory usage.
1041  *
1042  * @param bool $exact Print exact byte values instead of kibibytes (default: false)
1043  */
1044 function wfDebugMem( $exact = false ) {
1045         $mem = memory_get_usage();
1046         if ( !$exact ) {
1047                 $mem = floor( $mem / 1024 ) . ' KiB';
1048         } else {
1049                 $mem .= ' B';
1050         }
1051         wfDebug( "Memory usage: $mem\n" );
1052 }
1053
1054 /**
1055  * Send a line to a supplementary debug log file, if configured, or main debug
1056  * log if not.
1057  *
1058  * To configure a supplementary log file, set $wgDebugLogGroups[$logGroup] to
1059  * a string filename or an associative array mapping 'destination' to the
1060  * desired filename. The associative array may also contain a 'sample' key
1061  * with an integer value, specifying a sampling factor. Sampled log events
1062  * will be emitted with a 1 in N random chance.
1063  *
1064  * @since 1.23 support for sampling log messages via $wgDebugLogGroups.
1065  * @since 1.25 support for additional context data
1066  * @since 1.25 sample behavior dependent on configured $wgMWLoggerDefaultSpi
1067  *
1068  * @param string $logGroup
1069  * @param string $text
1070  * @param string|bool $dest Destination of the message:
1071  *     - 'all': both to the log and HTML (debug toolbar or HTML comments)
1072  *     - 'private': only to the specific log if set in $wgDebugLogGroups and
1073  *       discarded otherwise
1074  *   For backward compatibility, it can also take a boolean:
1075  *     - true: same as 'all'
1076  *     - false: same as 'private'
1077  * @param array $context Additional logging context data
1078  */
1079 function wfDebugLog(
1080         $logGroup, $text, $dest = 'all', array $context = []
1081 ) {
1082         $text = trim( $text );
1083
1084         $logger = LoggerFactory::getInstance( $logGroup );
1085         $context['private'] = ( $dest === false || $dest === 'private' );
1086         $logger->info( $text, $context );
1087 }
1088
1089 /**
1090  * Log for database errors
1091  *
1092  * @since 1.25 support for additional context data
1093  *
1094  * @param string $text Database error message.
1095  * @param array $context Additional logging context data
1096  */
1097 function wfLogDBError( $text, array $context = [] ) {
1098         $logger = LoggerFactory::getInstance( 'wfLogDBError' );
1099         $logger->error( trim( $text ), $context );
1100 }
1101
1102 /**
1103  * Throws a warning that $function is deprecated
1104  *
1105  * @param string $function
1106  * @param string|bool $version Version of MediaWiki that the function
1107  *    was deprecated in (Added in 1.19).
1108  * @param string|bool $component Added in 1.19.
1109  * @param int $callerOffset How far up the call stack is the original
1110  *    caller. 2 = function that called the function that called
1111  *    wfDeprecated (Added in 1.20)
1112  *
1113  * @return null
1114  */
1115 function wfDeprecated( $function, $version = false, $component = false, $callerOffset = 2 ) {
1116         MWDebug::deprecated( $function, $version, $component, $callerOffset + 1 );
1117 }
1118
1119 /**
1120  * Send a warning either to the debug log or in a PHP error depending on
1121  * $wgDevelopmentWarnings. To log warnings in production, use wfLogWarning() instead.
1122  *
1123  * @param string $msg Message to send
1124  * @param int $callerOffset Number of items to go back in the backtrace to
1125  *        find the correct caller (1 = function calling wfWarn, ...)
1126  * @param int $level PHP error level; defaults to E_USER_NOTICE;
1127  *        only used when $wgDevelopmentWarnings is true
1128  */
1129 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
1130         MWDebug::warning( $msg, $callerOffset + 1, $level, 'auto' );
1131 }
1132
1133 /**
1134  * Send a warning as a PHP error and the debug log. This is intended for logging
1135  * warnings in production. For logging development warnings, use WfWarn instead.
1136  *
1137  * @param string $msg Message to send
1138  * @param int $callerOffset Number of items to go back in the backtrace to
1139  *        find the correct caller (1 = function calling wfLogWarning, ...)
1140  * @param int $level PHP error level; defaults to E_USER_WARNING
1141  */
1142 function wfLogWarning( $msg, $callerOffset = 1, $level = E_USER_WARNING ) {
1143         MWDebug::warning( $msg, $callerOffset + 1, $level, 'production' );
1144 }
1145
1146 /**
1147  * Log to a file without getting "file size exceeded" signals.
1148  *
1149  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
1150  * send lines to the specified port, prefixed by the specified prefix and a space.
1151  * @since 1.25 support for additional context data
1152  *
1153  * @param string $text
1154  * @param string $file Filename
1155  * @param array $context Additional logging context data
1156  * @throws MWException
1157  * @deprecated since 1.25 Use \MediaWiki\Logger\LegacyLogger::emit or UDPTransport
1158  */
1159 function wfErrorLog( $text, $file, array $context = [] ) {
1160         wfDeprecated( __METHOD__, '1.25' );
1161         $logger = LoggerFactory::getInstance( 'wfErrorLog' );
1162         $context['destination'] = $file;
1163         $logger->info( trim( $text ), $context );
1164 }
1165
1166 /**
1167  * @todo document
1168  * @todo Move logic to MediaWiki.php
1169  */
1170 function wfLogProfilingData() {
1171         global $wgDebugLogGroups, $wgDebugRawPage;
1172
1173         $context = RequestContext::getMain();
1174         $request = $context->getRequest();
1175
1176         $profiler = Profiler::instance();
1177         $profiler->setContext( $context );
1178         $profiler->logData();
1179
1180         // Send out any buffered statsd metrics as needed
1181         MediaWiki::emitBufferedStatsdData(
1182                 MediaWikiServices::getInstance()->getStatsdDataFactory(),
1183                 $context->getConfig()
1184         );
1185
1186         // Profiling must actually be enabled...
1187         if ( $profiler instanceof ProfilerStub ) {
1188                 return;
1189         }
1190
1191         if ( isset( $wgDebugLogGroups['profileoutput'] )
1192                 && $wgDebugLogGroups['profileoutput'] === false
1193         ) {
1194                 // Explicitly disabled
1195                 return;
1196         }
1197         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
1198                 return;
1199         }
1200
1201         $ctx = [ 'elapsed' => $request->getElapsedTime() ];
1202         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
1203                 $ctx['forwarded_for'] = $_SERVER['HTTP_X_FORWARDED_FOR'];
1204         }
1205         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
1206                 $ctx['client_ip'] = $_SERVER['HTTP_CLIENT_IP'];
1207         }
1208         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
1209                 $ctx['from'] = $_SERVER['HTTP_FROM'];
1210         }
1211         if ( isset( $ctx['forwarded_for'] ) ||
1212                 isset( $ctx['client_ip'] ) ||
1213                 isset( $ctx['from'] ) ) {
1214                 $ctx['proxy'] = $_SERVER['REMOTE_ADDR'];
1215         }
1216
1217         // Don't load $wgUser at this late stage just for statistics purposes
1218         // @todo FIXME: We can detect some anons even if it is not loaded.
1219         // See User::getId()
1220         $user = $context->getUser();
1221         $ctx['anon'] = $user->isItemLoaded( 'id' ) && $user->isAnon();
1222
1223         // Command line script uses a FauxRequest object which does not have
1224         // any knowledge about an URL and throw an exception instead.
1225         try {
1226                 $ctx['url'] = urldecode( $request->getRequestURL() );
1227         } catch ( Exception $ignored ) {
1228                 // no-op
1229         }
1230
1231         $ctx['output'] = $profiler->getOutput();
1232
1233         $log = LoggerFactory::getInstance( 'profileoutput' );
1234         $log->info( "Elapsed: {elapsed}; URL: <{url}>\n{output}", $ctx );
1235 }
1236
1237 /**
1238  * Increment a statistics counter
1239  *
1240  * @param string $key
1241  * @param int $count
1242  * @return void
1243  */
1244 function wfIncrStats( $key, $count = 1 ) {
1245         $stats = MediaWikiServices::getInstance()->getStatsdDataFactory();
1246         $stats->updateCount( $key, $count );
1247 }
1248
1249 /**
1250  * Check whether the wiki is in read-only mode.
1251  *
1252  * @return bool
1253  */
1254 function wfReadOnly() {
1255         return MediaWikiServices::getInstance()->getReadOnlyMode()
1256                 ->isReadOnly();
1257 }
1258
1259 /**
1260  * Check if the site is in read-only mode and return the message if so
1261  *
1262  * This checks wfConfiguredReadOnlyReason() and the main load balancer
1263  * for replica DB lag. This may result in DB connection being made.
1264  *
1265  * @return string|bool String when in read-only mode; false otherwise
1266  */
1267 function wfReadOnlyReason() {
1268         return MediaWikiServices::getInstance()->getReadOnlyMode()
1269                 ->getReason();
1270 }
1271
1272 /**
1273  * Get the value of $wgReadOnly or the contents of $wgReadOnlyFile.
1274  *
1275  * @return string|bool String when in read-only mode; false otherwise
1276  * @since 1.27
1277  */
1278 function wfConfiguredReadOnlyReason() {
1279         return MediaWikiServices::getInstance()->getConfiguredReadOnlyMode()
1280                 ->getReason();
1281 }
1282
1283 /**
1284  * Return a Language object from $langcode
1285  *
1286  * @param Language|string|bool $langcode Either:
1287  *                  - a Language object
1288  *                  - code of the language to get the message for, if it is
1289  *                    a valid code create a language for that language, if
1290  *                    it is a string but not a valid code then make a basic
1291  *                    language object
1292  *                  - a boolean: if it's false then use the global object for
1293  *                    the current user's language (as a fallback for the old parameter
1294  *                    functionality), or if it is true then use global object
1295  *                    for the wiki's content language.
1296  * @return Language
1297  */
1298 function wfGetLangObj( $langcode = false ) {
1299         # Identify which language to get or create a language object for.
1300         # Using is_object here due to Stub objects.
1301         if ( is_object( $langcode ) ) {
1302                 # Great, we already have the object (hopefully)!
1303                 return $langcode;
1304         }
1305
1306         global $wgContLang, $wgLanguageCode;
1307         if ( $langcode === true || $langcode === $wgLanguageCode ) {
1308                 # $langcode is the language code of the wikis content language object.
1309                 # or it is a boolean and value is true
1310                 return $wgContLang;
1311         }
1312
1313         global $wgLang;
1314         if ( $langcode === false || $langcode === $wgLang->getCode() ) {
1315                 # $langcode is the language code of user language object.
1316                 # or it was a boolean and value is false
1317                 return $wgLang;
1318         }
1319
1320         $validCodes = array_keys( Language::fetchLanguageNames() );
1321         if ( in_array( $langcode, $validCodes ) ) {
1322                 # $langcode corresponds to a valid language.
1323                 return Language::factory( $langcode );
1324         }
1325
1326         # $langcode is a string, but not a valid language code; use content language.
1327         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
1328         return $wgContLang;
1329 }
1330
1331 /**
1332  * This is the function for getting translated interface messages.
1333  *
1334  * @see Message class for documentation how to use them.
1335  * @see https://www.mediawiki.org/wiki/Manual:Messages_API
1336  *
1337  * This function replaces all old wfMsg* functions.
1338  *
1339  * @param string|string[]|MessageSpecifier $key Message key, or array of keys, or a MessageSpecifier
1340  * @param string|string[] ...$params Normal message parameters
1341  * @return Message
1342  *
1343  * @since 1.17
1344  *
1345  * @see Message::__construct
1346  */
1347 function wfMessage( $key, ...$params ) {
1348         $message = new Message( $key );
1349
1350         // We call Message::params() to reduce code duplication
1351         if ( $params ) {
1352                 $message->params( ...$params );
1353         }
1354
1355         return $message;
1356 }
1357
1358 /**
1359  * This function accepts multiple message keys and returns a message instance
1360  * for the first message which is non-empty. If all messages are empty then an
1361  * instance of the first message key is returned.
1362  *
1363  * @param string ...$keys Message keys
1364  * @return Message
1365  *
1366  * @since 1.18
1367  *
1368  * @see Message::newFallbackSequence
1369  */
1370 function wfMessageFallback( ...$keys ) {
1371         return Message::newFallbackSequence( ...$keys );
1372 }
1373
1374 /**
1375  * Replace message parameter keys on the given formatted output.
1376  *
1377  * @param string $message
1378  * @param array $args
1379  * @return string
1380  * @private
1381  */
1382 function wfMsgReplaceArgs( $message, $args ) {
1383         # Fix windows line-endings
1384         # Some messages are split with explode("\n", $msg)
1385         $message = str_replace( "\r", '', $message );
1386
1387         // Replace arguments
1388         if ( is_array( $args ) && $args ) {
1389                 if ( is_array( $args[0] ) ) {
1390                         $args = array_values( $args[0] );
1391                 }
1392                 $replacementKeys = [];
1393                 foreach ( $args as $n => $param ) {
1394                         $replacementKeys['$' . ( $n + 1 )] = $param;
1395                 }
1396                 $message = strtr( $message, $replacementKeys );
1397         }
1398
1399         return $message;
1400 }
1401
1402 /**
1403  * Fetch server name for use in error reporting etc.
1404  * Use real server name if available, so we know which machine
1405  * in a server farm generated the current page.
1406  *
1407  * @return string
1408  */
1409 function wfHostname() {
1410         static $host;
1411         if ( is_null( $host ) ) {
1412                 # Hostname overriding
1413                 global $wgOverrideHostname;
1414                 if ( $wgOverrideHostname !== false ) {
1415                         # Set static and skip any detection
1416                         $host = $wgOverrideHostname;
1417                         return $host;
1418                 }
1419
1420                 if ( function_exists( 'posix_uname' ) ) {
1421                         // This function not present on Windows
1422                         $uname = posix_uname();
1423                 } else {
1424                         $uname = false;
1425                 }
1426                 if ( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1427                         $host = $uname['nodename'];
1428                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1429                         # Windows computer name
1430                         $host = getenv( 'COMPUTERNAME' );
1431                 } else {
1432                         # This may be a virtual server.
1433                         $host = $_SERVER['SERVER_NAME'];
1434                 }
1435         }
1436         return $host;
1437 }
1438
1439 /**
1440  * Returns a script tag that stores the amount of time it took MediaWiki to
1441  * handle the request in milliseconds as 'wgBackendResponseTime'.
1442  *
1443  * If $wgShowHostnames is true, the script will also set 'wgHostname' to the
1444  * hostname of the server handling the request.
1445  *
1446  * @param string|null $nonce Value from OutputPage::getCSPNonce
1447  * @return string|WrappedString HTML
1448  */
1449 function wfReportTime( $nonce = null ) {
1450         global $wgShowHostnames;
1451
1452         $elapsed = ( microtime( true ) - $_SERVER['REQUEST_TIME_FLOAT'] );
1453         // seconds to milliseconds
1454         $responseTime = round( $elapsed * 1000 );
1455         $reportVars = [ 'wgBackendResponseTime' => $responseTime ];
1456         if ( $wgShowHostnames ) {
1457                 $reportVars['wgHostname'] = wfHostname();
1458         }
1459         return Skin::makeVariablesScript( $reportVars, $nonce );
1460 }
1461
1462 /**
1463  * Safety wrapper for debug_backtrace().
1464  *
1465  * Will return an empty array if debug_backtrace is disabled, otherwise
1466  * the output from debug_backtrace() (trimmed).
1467  *
1468  * @param int $limit This parameter can be used to limit the number of stack frames returned
1469  *
1470  * @return array Array of backtrace information
1471  */
1472 function wfDebugBacktrace( $limit = 0 ) {
1473         static $disabled = null;
1474
1475         if ( is_null( $disabled ) ) {
1476                 $disabled = !function_exists( 'debug_backtrace' );
1477                 if ( $disabled ) {
1478                         wfDebug( "debug_backtrace() is disabled\n" );
1479                 }
1480         }
1481         if ( $disabled ) {
1482                 return [];
1483         }
1484
1485         if ( $limit ) {
1486                 return array_slice( debug_backtrace( DEBUG_BACKTRACE_PROVIDE_OBJECT, $limit + 1 ), 1 );
1487         } else {
1488                 return array_slice( debug_backtrace(), 1 );
1489         }
1490 }
1491
1492 /**
1493  * Get a debug backtrace as a string
1494  *
1495  * @param bool|null $raw If true, the return value is plain text. If false, HTML.
1496  *   Defaults to $wgCommandLineMode if unset.
1497  * @return string
1498  * @since 1.25 Supports $raw parameter.
1499  */
1500 function wfBacktrace( $raw = null ) {
1501         global $wgCommandLineMode;
1502
1503         if ( $raw === null ) {
1504                 $raw = $wgCommandLineMode;
1505         }
1506
1507         if ( $raw ) {
1508                 $frameFormat = "%s line %s calls %s()\n";
1509                 $traceFormat = "%s";
1510         } else {
1511                 $frameFormat = "<li>%s line %s calls %s()</li>\n";
1512                 $traceFormat = "<ul>\n%s</ul>\n";
1513         }
1514
1515         $frames = array_map( function ( $frame ) use ( $frameFormat ) {
1516                 $file = !empty( $frame['file'] ) ? basename( $frame['file'] ) : '-';
1517                 $line = $frame['line'] ?? '-';
1518                 $call = $frame['function'];
1519                 if ( !empty( $frame['class'] ) ) {
1520                         $call = $frame['class'] . $frame['type'] . $call;
1521                 }
1522                 return sprintf( $frameFormat, $file, $line, $call );
1523         }, wfDebugBacktrace() );
1524
1525         return sprintf( $traceFormat, implode( '', $frames ) );
1526 }
1527
1528 /**
1529  * Get the name of the function which called this function
1530  * wfGetCaller( 1 ) is the function with the wfGetCaller() call (ie. __FUNCTION__)
1531  * wfGetCaller( 2 ) [default] is the caller of the function running wfGetCaller()
1532  * wfGetCaller( 3 ) is the parent of that.
1533  *
1534  * @param int $level
1535  * @return string
1536  */
1537 function wfGetCaller( $level = 2 ) {
1538         $backtrace = wfDebugBacktrace( $level + 1 );
1539         if ( isset( $backtrace[$level] ) ) {
1540                 return wfFormatStackFrame( $backtrace[$level] );
1541         } else {
1542                 return 'unknown';
1543         }
1544 }
1545
1546 /**
1547  * Return a string consisting of callers in the stack. Useful sometimes
1548  * for profiling specific points.
1549  *
1550  * @param int $limit The maximum depth of the stack frame to return, or false for the entire stack.
1551  * @return string
1552  */
1553 function wfGetAllCallers( $limit = 3 ) {
1554         $trace = array_reverse( wfDebugBacktrace() );
1555         if ( !$limit || $limit > count( $trace ) - 1 ) {
1556                 $limit = count( $trace ) - 1;
1557         }
1558         $trace = array_slice( $trace, -$limit - 1, $limit );
1559         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1560 }
1561
1562 /**
1563  * Return a string representation of frame
1564  *
1565  * @param array $frame
1566  * @return string
1567  */
1568 function wfFormatStackFrame( $frame ) {
1569         if ( !isset( $frame['function'] ) ) {
1570                 return 'NO_FUNCTION_GIVEN';
1571         }
1572         return isset( $frame['class'] ) && isset( $frame['type'] ) ?
1573                 $frame['class'] . $frame['type'] . $frame['function'] :
1574                 $frame['function'];
1575 }
1576
1577 /* Some generic result counters, pulled out of SearchEngine */
1578
1579 /**
1580  * @todo document
1581  *
1582  * @param int $offset
1583  * @param int $limit
1584  * @return string
1585  */
1586 function wfShowingResults( $offset, $limit ) {
1587         return wfMessage( 'showingresults' )->numParams( $limit, $offset + 1 )->parse();
1588 }
1589
1590 /**
1591  * Whether the client accept gzip encoding
1592  *
1593  * Uses the Accept-Encoding header to check if the client supports gzip encoding.
1594  * Use this when considering to send a gzip-encoded response to the client.
1595  *
1596  * @param bool $force Forces another check even if we already have a cached result.
1597  * @return bool
1598  */
1599 function wfClientAcceptsGzip( $force = false ) {
1600         static $result = null;
1601         if ( $result === null || $force ) {
1602                 $result = false;
1603                 if ( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1604                         # @todo FIXME: We may want to blacklist some broken browsers
1605                         $m = [];
1606                         if ( preg_match(
1607                                         '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1608                                         $_SERVER['HTTP_ACCEPT_ENCODING'],
1609                                         $m
1610                                 )
1611                         ) {
1612                                 if ( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1613                                         $result = false;
1614                                         return $result;
1615                                 }
1616                                 wfDebug( "wfClientAcceptsGzip: client accepts gzip.\n" );
1617                                 $result = true;
1618                         }
1619                 }
1620         }
1621         return $result;
1622 }
1623
1624 /**
1625  * Escapes the given text so that it may be output using addWikiText()
1626  * without any linking, formatting, etc. making its way through. This
1627  * is achieved by substituting certain characters with HTML entities.
1628  * As required by the callers, "<nowiki>" is not used.
1629  *
1630  * @param string $text Text to be escaped
1631  * @param-taint $text escapes_html
1632  * @return string
1633  */
1634 function wfEscapeWikiText( $text ) {
1635         global $wgEnableMagicLinks;
1636         static $repl = null, $repl2 = null;
1637         if ( $repl === null || defined( 'MW_PARSER_TEST' ) || defined( 'MW_PHPUNIT_TEST' ) ) {
1638                 // Tests depend upon being able to change $wgEnableMagicLinks, so don't cache
1639                 // in those situations
1640                 $repl = [
1641                         '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
1642                         '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
1643                         '{' => '&#123;', '|' => '&#124;', '}' => '&#125;', ';' => '&#59;',
1644                         "\n#" => "\n&#35;", "\r#" => "\r&#35;",
1645                         "\n*" => "\n&#42;", "\r*" => "\r&#42;",
1646                         "\n:" => "\n&#58;", "\r:" => "\r&#58;",
1647                         "\n " => "\n&#32;", "\r " => "\r&#32;",
1648                         "\n\n" => "\n&#10;", "\r\n" => "&#13;\n",
1649                         "\n\r" => "\n&#13;", "\r\r" => "\r&#13;",
1650                         "\n\t" => "\n&#9;", "\r\t" => "\r&#9;", // "\n\t\n" is treated like "\n\n"
1651                         "\n----" => "\n&#45;---", "\r----" => "\r&#45;---",
1652                         '__' => '_&#95;', '://' => '&#58;//',
1653                 ];
1654
1655                 $magicLinks = array_keys( array_filter( $wgEnableMagicLinks ) );
1656                 // We have to catch everything "\s" matches in PCRE
1657                 foreach ( $magicLinks as $magic ) {
1658                         $repl["$magic "] = "$magic&#32;";
1659                         $repl["$magic\t"] = "$magic&#9;";
1660                         $repl["$magic\r"] = "$magic&#13;";
1661                         $repl["$magic\n"] = "$magic&#10;";
1662                         $repl["$magic\f"] = "$magic&#12;";
1663                 }
1664
1665                 // And handle protocols that don't use "://"
1666                 global $wgUrlProtocols;
1667                 $repl2 = [];
1668                 foreach ( $wgUrlProtocols as $prot ) {
1669                         if ( substr( $prot, -1 ) === ':' ) {
1670                                 $repl2[] = preg_quote( substr( $prot, 0, -1 ), '/' );
1671                         }
1672                 }
1673                 $repl2 = $repl2 ? '/\b(' . implode( '|', $repl2 ) . '):/i' : '/^(?!)/';
1674         }
1675         $text = substr( strtr( "\n$text", $repl ), 1 );
1676         $text = preg_replace( $repl2, '$1&#58;', $text );
1677         return $text;
1678 }
1679
1680 /**
1681  * Sets dest to source and returns the original value of dest
1682  * If source is NULL, it just returns the value, it doesn't set the variable
1683  * If force is true, it will set the value even if source is NULL
1684  *
1685  * @param mixed &$dest
1686  * @param mixed $source
1687  * @param bool $force
1688  * @return mixed
1689  */
1690 function wfSetVar( &$dest, $source, $force = false ) {
1691         $temp = $dest;
1692         if ( !is_null( $source ) || $force ) {
1693                 $dest = $source;
1694         }
1695         return $temp;
1696 }
1697
1698 /**
1699  * As for wfSetVar except setting a bit
1700  *
1701  * @param int &$dest
1702  * @param int $bit
1703  * @param bool $state
1704  *
1705  * @return bool
1706  */
1707 function wfSetBit( &$dest, $bit, $state = true ) {
1708         $temp = (bool)( $dest & $bit );
1709         if ( !is_null( $state ) ) {
1710                 if ( $state ) {
1711                         $dest |= $bit;
1712                 } else {
1713                         $dest &= ~$bit;
1714                 }
1715         }
1716         return $temp;
1717 }
1718
1719 /**
1720  * A wrapper around the PHP function var_export().
1721  * Either print it or add it to the regular output ($wgOut).
1722  *
1723  * @param mixed $var A PHP variable to dump.
1724  */
1725 function wfVarDump( $var ) {
1726         global $wgOut;
1727         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
1728         if ( headers_sent() || !isset( $wgOut ) || !is_object( $wgOut ) ) {
1729                 print $s;
1730         } else {
1731                 $wgOut->addHTML( $s );
1732         }
1733 }
1734
1735 /**
1736  * Provide a simple HTTP error.
1737  *
1738  * @param int|string $code
1739  * @param string $label
1740  * @param string $desc
1741  */
1742 function wfHttpError( $code, $label, $desc ) {
1743         global $wgOut;
1744         HttpStatus::header( $code );
1745         if ( $wgOut ) {
1746                 $wgOut->disable();
1747                 $wgOut->sendCacheControl();
1748         }
1749
1750         MediaWiki\HeaderCallback::warnIfHeadersSent();
1751         header( 'Content-type: text/html; charset=utf-8' );
1752         print '<!DOCTYPE html>' .
1753                 '<html><head><title>' .
1754                 htmlspecialchars( $label ) .
1755                 '</title></head><body><h1>' .
1756                 htmlspecialchars( $label ) .
1757                 '</h1><p>' .
1758                 nl2br( htmlspecialchars( $desc ) ) .
1759                 "</p></body></html>\n";
1760 }
1761
1762 /**
1763  * Clear away any user-level output buffers, discarding contents.
1764  *
1765  * Suitable for 'starting afresh', for instance when streaming
1766  * relatively large amounts of data without buffering, or wanting to
1767  * output image files without ob_gzhandler's compression.
1768  *
1769  * The optional $resetGzipEncoding parameter controls suppression of
1770  * the Content-Encoding header sent by ob_gzhandler; by default it
1771  * is left. See comments for wfClearOutputBuffers() for why it would
1772  * be used.
1773  *
1774  * Note that some PHP configuration options may add output buffer
1775  * layers which cannot be removed; these are left in place.
1776  *
1777  * @param bool $resetGzipEncoding
1778  */
1779 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
1780         if ( $resetGzipEncoding ) {
1781                 // Suppress Content-Encoding and Content-Length
1782                 // headers from OutputHandler::handle.
1783                 global $wgDisableOutputCompression;
1784                 $wgDisableOutputCompression = true;
1785         }
1786         while ( $status = ob_get_status() ) {
1787                 if ( isset( $status['flags'] ) ) {
1788                         $flags = PHP_OUTPUT_HANDLER_CLEANABLE | PHP_OUTPUT_HANDLER_REMOVABLE;
1789                         $deleteable = ( $status['flags'] & $flags ) === $flags;
1790                 } elseif ( isset( $status['del'] ) ) {
1791                         $deleteable = $status['del'];
1792                 } else {
1793                         // Guess that any PHP-internal setting can't be removed.
1794                         $deleteable = $status['type'] !== 0; /* PHP_OUTPUT_HANDLER_INTERNAL */
1795                 }
1796                 if ( !$deleteable ) {
1797                         // Give up, and hope the result doesn't break
1798                         // output behavior.
1799                         break;
1800                 }
1801                 if ( $status['name'] === 'MediaWikiTestCase::wfResetOutputBuffersBarrier' ) {
1802                         // Unit testing barrier to prevent this function from breaking PHPUnit.
1803                         break;
1804                 }
1805                 if ( !ob_end_clean() ) {
1806                         // Could not remove output buffer handler; abort now
1807                         // to avoid getting in some kind of infinite loop.
1808                         break;
1809                 }
1810                 if ( $resetGzipEncoding ) {
1811                         if ( $status['name'] == 'ob_gzhandler' ) {
1812                                 // Reset the 'Content-Encoding' field set by this handler
1813                                 // so we can start fresh.
1814                                 header_remove( 'Content-Encoding' );
1815                                 break;
1816                         }
1817                 }
1818         }
1819 }
1820
1821 /**
1822  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
1823  *
1824  * Clear away output buffers, but keep the Content-Encoding header
1825  * produced by ob_gzhandler, if any.
1826  *
1827  * This should be used for HTTP 304 responses, where you need to
1828  * preserve the Content-Encoding header of the real result, but
1829  * also need to suppress the output of ob_gzhandler to keep to spec
1830  * and avoid breaking Firefox in rare cases where the headers and
1831  * body are broken over two packets.
1832  */
1833 function wfClearOutputBuffers() {
1834         wfResetOutputBuffers( false );
1835 }
1836
1837 /**
1838  * Converts an Accept-* header into an array mapping string values to quality
1839  * factors
1840  *
1841  * @param string $accept
1842  * @param string $def Default
1843  * @return float[] Associative array of string => float pairs
1844  */
1845 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
1846         # No arg means accept anything (per HTTP spec)
1847         if ( !$accept ) {
1848                 return [ $def => 1.0 ];
1849         }
1850
1851         $prefs = [];
1852
1853         $parts = explode( ',', $accept );
1854
1855         foreach ( $parts as $part ) {
1856                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
1857                 $values = explode( ';', trim( $part ) );
1858                 $match = [];
1859                 if ( count( $values ) == 1 ) {
1860                         $prefs[$values[0]] = 1.0;
1861                 } elseif ( preg_match( '/q\s*=\s*(\d*\.\d+)/', $values[1], $match ) ) {
1862                         $prefs[$values[0]] = floatval( $match[1] );
1863                 }
1864         }
1865
1866         return $prefs;
1867 }
1868
1869 /**
1870  * Checks if a given MIME type matches any of the keys in the given
1871  * array. Basic wildcards are accepted in the array keys.
1872  *
1873  * Returns the matching MIME type (or wildcard) if a match, otherwise
1874  * NULL if no match.
1875  *
1876  * @param string $type
1877  * @param array $avail
1878  * @return string
1879  * @private
1880  */
1881 function mimeTypeMatch( $type, $avail ) {
1882         if ( array_key_exists( $type, $avail ) ) {
1883                 return $type;
1884         } else {
1885                 $mainType = explode( '/', $type )[0];
1886                 if ( array_key_exists( "$mainType/*", $avail ) ) {
1887                         return "$mainType/*";
1888                 } elseif ( array_key_exists( '*/*', $avail ) ) {
1889                         return '*/*';
1890                 } else {
1891                         return null;
1892                 }
1893         }
1894 }
1895
1896 /**
1897  * Returns the 'best' match between a client's requested internet media types
1898  * and the server's list of available types. Each list should be an associative
1899  * array of type to preference (preference is a float between 0.0 and 1.0).
1900  * Wildcards in the types are acceptable.
1901  *
1902  * @param array $cprefs Client's acceptable type list
1903  * @param array $sprefs Server's offered types
1904  * @return string
1905  *
1906  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
1907  * XXX: generalize to negotiate other stuff
1908  */
1909 function wfNegotiateType( $cprefs, $sprefs ) {
1910         $combine = [];
1911
1912         foreach ( array_keys( $sprefs ) as $type ) {
1913                 $subType = explode( '/', $type )[1];
1914                 if ( $subType != '*' ) {
1915                         $ckey = mimeTypeMatch( $type, $cprefs );
1916                         if ( $ckey ) {
1917                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
1918                         }
1919                 }
1920         }
1921
1922         foreach ( array_keys( $cprefs ) as $type ) {
1923                 $subType = explode( '/', $type )[1];
1924                 if ( $subType != '*' && !array_key_exists( $type, $sprefs ) ) {
1925                         $skey = mimeTypeMatch( $type, $sprefs );
1926                         if ( $skey ) {
1927                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
1928                         }
1929                 }
1930         }
1931
1932         $bestq = 0;
1933         $besttype = null;
1934
1935         foreach ( array_keys( $combine ) as $type ) {
1936                 if ( $combine[$type] > $bestq ) {
1937                         $besttype = $type;
1938                         $bestq = $combine[$type];
1939                 }
1940         }
1941
1942         return $besttype;
1943 }
1944
1945 /**
1946  * Reference-counted warning suppression
1947  *
1948  * @deprecated since 1.26, use Wikimedia\suppressWarnings() directly
1949  * @param bool $end
1950  */
1951 function wfSuppressWarnings( $end = false ) {
1952         Wikimedia\suppressWarnings( $end );
1953 }
1954
1955 /**
1956  * @deprecated since 1.26, use Wikimedia\restoreWarnings() directly
1957  * Restore error level to previous value
1958  */
1959 function wfRestoreWarnings() {
1960         Wikimedia\restoreWarnings();
1961 }
1962
1963 /**
1964  * Get a timestamp string in one of various formats
1965  *
1966  * @param mixed $outputtype A timestamp in one of the supported formats, the
1967  *   function will autodetect which format is supplied and act accordingly.
1968  * @param mixed $ts Optional timestamp to convert, default 0 for the current time
1969  * @return string|bool String / false The same date in the format specified in $outputtype or false
1970  */
1971 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
1972         $ret = MWTimestamp::convert( $outputtype, $ts );
1973         if ( $ret === false ) {
1974                 wfDebug( "wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n" );
1975         }
1976         return $ret;
1977 }
1978
1979 /**
1980  * Return a formatted timestamp, or null if input is null.
1981  * For dealing with nullable timestamp columns in the database.
1982  *
1983  * @param int $outputtype
1984  * @param string|null $ts
1985  * @return string
1986  */
1987 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
1988         if ( is_null( $ts ) ) {
1989                 return null;
1990         } else {
1991                 return wfTimestamp( $outputtype, $ts );
1992         }
1993 }
1994
1995 /**
1996  * Convenience function; returns MediaWiki timestamp for the present time.
1997  *
1998  * @return string
1999  */
2000 function wfTimestampNow() {
2001         # return NOW
2002         return MWTimestamp::now( TS_MW );
2003 }
2004
2005 /**
2006  * Check if the operating system is Windows
2007  *
2008  * @return bool True if it's Windows, false otherwise.
2009  */
2010 function wfIsWindows() {
2011         static $isWindows = null;
2012         if ( $isWindows === null ) {
2013                 $isWindows = strtoupper( substr( PHP_OS, 0, 3 ) ) === 'WIN';
2014         }
2015         return $isWindows;
2016 }
2017
2018 /**
2019  * Check if we are running under HHVM
2020  *
2021  * @return bool
2022  */
2023 function wfIsHHVM() {
2024         return defined( 'HHVM_VERSION' );
2025 }
2026
2027 /**
2028  * Check if we are running from the commandline
2029  *
2030  * @since 1.31
2031  * @return bool
2032  */
2033 function wfIsCLI() {
2034         return PHP_SAPI === 'cli' || PHP_SAPI === 'phpdbg';
2035 }
2036
2037 /**
2038  * Tries to get the system directory for temporary files. First
2039  * $wgTmpDirectory is checked, and then the TMPDIR, TMP, and TEMP
2040  * environment variables are then checked in sequence, then
2041  * sys_get_temp_dir(), then upload_tmp_dir from php.ini.
2042  *
2043  * NOTE: When possible, use instead the tmpfile() function to create
2044  * temporary files to avoid race conditions on file creation, etc.
2045  *
2046  * @return string
2047  */
2048 function wfTempDir() {
2049         global $wgTmpDirectory;
2050
2051         if ( $wgTmpDirectory !== false ) {
2052                 return $wgTmpDirectory;
2053         }
2054
2055         return TempFSFile::getUsableTempDirectory();
2056 }
2057
2058 /**
2059  * Make directory, and make all parent directories if they don't exist
2060  *
2061  * @param string $dir Full path to directory to create
2062  * @param int|null $mode Chmod value to use, default is $wgDirectoryMode
2063  * @param string|null $caller Optional caller param for debugging.
2064  * @throws MWException
2065  * @return bool
2066  */
2067 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2068         global $wgDirectoryMode;
2069
2070         if ( FileBackend::isStoragePath( $dir ) ) { // sanity
2071                 throw new MWException( __FUNCTION__ . " given storage path '$dir'." );
2072         }
2073
2074         if ( !is_null( $caller ) ) {
2075                 wfDebug( "$caller: called wfMkdirParents($dir)\n" );
2076         }
2077
2078         if ( strval( $dir ) === '' || is_dir( $dir ) ) {
2079                 return true;
2080         }
2081
2082         $dir = str_replace( [ '\\', '/' ], DIRECTORY_SEPARATOR, $dir );
2083
2084         if ( is_null( $mode ) ) {
2085                 $mode = $wgDirectoryMode;
2086         }
2087
2088         // Turn off the normal warning, we're doing our own below
2089         Wikimedia\suppressWarnings();
2090         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2091         Wikimedia\restoreWarnings();
2092
2093         if ( !$ok ) {
2094                 // directory may have been created on another request since we last checked
2095                 if ( is_dir( $dir ) ) {
2096                         return true;
2097                 }
2098
2099                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2100                 wfLogWarning( sprintf( "failed to mkdir \"%s\" mode 0%o", $dir, $mode ) );
2101         }
2102         return $ok;
2103 }
2104
2105 /**
2106  * Remove a directory and all its content.
2107  * Does not hide error.
2108  * @param string $dir
2109  */
2110 function wfRecursiveRemoveDir( $dir ) {
2111         wfDebug( __FUNCTION__ . "( $dir )\n" );
2112         // taken from https://secure.php.net/manual/en/function.rmdir.php#98622
2113         if ( is_dir( $dir ) ) {
2114                 $objects = scandir( $dir );
2115                 foreach ( $objects as $object ) {
2116                         if ( $object != "." && $object != ".." ) {
2117                                 if ( filetype( $dir . '/' . $object ) == "dir" ) {
2118                                         wfRecursiveRemoveDir( $dir . '/' . $object );
2119                                 } else {
2120                                         unlink( $dir . '/' . $object );
2121                                 }
2122                         }
2123                 }
2124                 reset( $objects );
2125                 rmdir( $dir );
2126         }
2127 }
2128
2129 /**
2130  * @param int $nr The number to format
2131  * @param int $acc The number of digits after the decimal point, default 2
2132  * @param bool $round Whether or not to round the value, default true
2133  * @return string
2134  */
2135 function wfPercent( $nr, $acc = 2, $round = true ) {
2136         $ret = sprintf( "%.${acc}f", $nr );
2137         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2138 }
2139
2140 /**
2141  * Safety wrapper around ini_get() for boolean settings.
2142  * The values returned from ini_get() are pre-normalized for settings
2143  * set via php.ini or php_flag/php_admin_flag... but *not*
2144  * for those set via php_value/php_admin_value.
2145  *
2146  * It's fairly common for people to use php_value instead of php_flag,
2147  * which can leave you with an 'off' setting giving a false positive
2148  * for code that just takes the ini_get() return value as a boolean.
2149  *
2150  * To make things extra interesting, setting via php_value accepts
2151  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2152  * Unrecognized values go false... again opposite PHP's own coercion
2153  * from string to bool.
2154  *
2155  * Luckily, 'properly' set settings will always come back as '0' or '1',
2156  * so we only have to worry about them and the 'improper' settings.
2157  *
2158  * I frickin' hate PHP... :P
2159  *
2160  * @param string $setting
2161  * @return bool
2162  */
2163 function wfIniGetBool( $setting ) {
2164         return wfStringToBool( ini_get( $setting ) );
2165 }
2166
2167 /**
2168  * Convert string value to boolean, when the following are interpreted as true:
2169  * - on
2170  * - true
2171  * - yes
2172  * - Any number, except 0
2173  * All other strings are interpreted as false.
2174  *
2175  * @param string $val
2176  * @return bool
2177  * @since 1.31
2178  */
2179 function wfStringToBool( $val ) {
2180         $val = strtolower( $val );
2181         // 'on' and 'true' can't have whitespace around them, but '1' can.
2182         return $val == 'on'
2183                 || $val == 'true'
2184                 || $val == 'yes'
2185                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2186 }
2187
2188 /**
2189  * Version of escapeshellarg() that works better on Windows.
2190  *
2191  * Originally, this fixed the incorrect use of single quotes on Windows
2192  * (https://bugs.php.net/bug.php?id=26285) and the locale problems on Linux in
2193  * PHP 5.2.6+ (bug backported to earlier distro releases of PHP).
2194  *
2195  * @param string $args,... strings to escape and glue together,
2196  *  or a single array of strings parameter
2197  * @return string
2198  * @deprecated since 1.30 use MediaWiki\Shell::escape()
2199  */
2200 function wfEscapeShellArg( /*...*/ ) {
2201         return Shell::escape( ...func_get_args() );
2202 }
2203
2204 /**
2205  * Execute a shell command, with time and memory limits mirrored from the PHP
2206  * configuration if supported.
2207  *
2208  * @param string|string[] $cmd If string, a properly shell-escaped command line,
2209  *   or an array of unescaped arguments, in which case each value will be escaped
2210  *   Example:   [ 'convert', '-font', 'font name' ] would produce "'convert' '-font' 'font name'"
2211  * @param null|mixed &$retval Optional, will receive the program's exit code.
2212  *   (non-zero is usually failure). If there is an error from
2213  *   read, select, or proc_open(), this will be set to -1.
2214  * @param array $environ Optional environment variables which should be
2215  *   added to the executed command environment.
2216  * @param array $limits Optional array with limits(filesize, memory, time, walltime)
2217  *   this overwrites the global wgMaxShell* limits.
2218  * @param array $options Array of options:
2219  *   - duplicateStderr: Set this to true to duplicate stderr to stdout,
2220  *     including errors from limit.sh
2221  *   - profileMethod: By default this function will profile based on the calling
2222  *     method. Set this to a string for an alternative method to profile from
2223  *
2224  * @return string Collected stdout as a string
2225  * @deprecated since 1.30 use class MediaWiki\Shell\Shell
2226  */
2227 function wfShellExec( $cmd, &$retval = null, $environ = [],
2228         $limits = [], $options = []
2229 ) {
2230         if ( Shell::isDisabled() ) {
2231                 $retval = 1;
2232                 // Backwards compatibility be upon us...
2233                 return 'Unable to run external programs, proc_open() is disabled.';
2234         }
2235
2236         if ( is_array( $cmd ) ) {
2237                 $cmd = Shell::escape( $cmd );
2238         }
2239
2240         $includeStderr = isset( $options['duplicateStderr'] ) && $options['duplicateStderr'];
2241         $profileMethod = $options['profileMethod'] ?? wfGetCaller();
2242
2243         try {
2244                 $result = Shell::command( [] )
2245                         ->unsafeParams( (array)$cmd )
2246                         ->environment( $environ )
2247                         ->limits( $limits )
2248                         ->includeStderr( $includeStderr )
2249                         ->profileMethod( $profileMethod )
2250                         // For b/c
2251                         ->restrict( Shell::RESTRICT_NONE )
2252                         ->execute();
2253         } catch ( ProcOpenError $ex ) {
2254                 $retval = -1;
2255                 return '';
2256         }
2257
2258         $retval = $result->getExitCode();
2259
2260         return $result->getStdout();
2261 }
2262
2263 /**
2264  * Execute a shell command, returning both stdout and stderr. Convenience
2265  * function, as all the arguments to wfShellExec can become unwieldy.
2266  *
2267  * @note This also includes errors from limit.sh, e.g. if $wgMaxShellFileSize is exceeded.
2268  * @param string|string[] $cmd If string, a properly shell-escaped command line,
2269  *   or an array of unescaped arguments, in which case each value will be escaped
2270  *   Example:   [ 'convert', '-font', 'font name' ] would produce "'convert' '-font' 'font name'"
2271  * @param null|mixed &$retval Optional, will receive the program's exit code.
2272  *   (non-zero is usually failure)
2273  * @param array $environ Optional environment variables which should be
2274  *   added to the executed command environment.
2275  * @param array $limits Optional array with limits(filesize, memory, time, walltime)
2276  *   this overwrites the global wgMaxShell* limits.
2277  * @return string Collected stdout and stderr as a string
2278  * @deprecated since 1.30 use class MediaWiki\Shell\Shell
2279  */
2280 function wfShellExecWithStderr( $cmd, &$retval = null, $environ = [], $limits = [] ) {
2281         return wfShellExec( $cmd, $retval, $environ, $limits,
2282                 [ 'duplicateStderr' => true, 'profileMethod' => wfGetCaller() ] );
2283 }
2284
2285 /**
2286  * Generate a shell-escaped command line string to run a MediaWiki cli script.
2287  * Note that $parameters should be a flat array and an option with an argument
2288  * should consist of two consecutive items in the array (do not use "--option value").
2289  *
2290  * @deprecated since 1.31, use Shell::makeScriptCommand()
2291  *
2292  * @param string $script MediaWiki cli script path
2293  * @param array $parameters Arguments and options to the script
2294  * @param array $options Associative array of options:
2295  *     'php': The path to the php executable
2296  *     'wrapper': Path to a PHP wrapper to handle the maintenance script
2297  * @return string
2298  */
2299 function wfShellWikiCmd( $script, array $parameters = [], array $options = [] ) {
2300         global $wgPhpCli;
2301         // Give site config file a chance to run the script in a wrapper.
2302         // The caller may likely want to call wfBasename() on $script.
2303         Hooks::run( 'wfShellWikiCmd', [ &$script, &$parameters, &$options ] );
2304         $cmd = [ $options['php'] ?? $wgPhpCli ];
2305         if ( isset( $options['wrapper'] ) ) {
2306                 $cmd[] = $options['wrapper'];
2307         }
2308         $cmd[] = $script;
2309         // Escape each parameter for shell
2310         return Shell::escape( array_merge( $cmd, $parameters ) );
2311 }
2312
2313 /**
2314  * wfMerge attempts to merge differences between three texts.
2315  * Returns true for a clean merge and false for failure or a conflict.
2316  *
2317  * @param string $old
2318  * @param string $mine
2319  * @param string $yours
2320  * @param string &$result
2321  * @param string|null &$mergeAttemptResult
2322  * @return bool
2323  */
2324 function wfMerge( $old, $mine, $yours, &$result, &$mergeAttemptResult = null ) {
2325         global $wgDiff3;
2326
2327         # This check may also protect against code injection in
2328         # case of broken installations.
2329         Wikimedia\suppressWarnings();
2330         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
2331         Wikimedia\restoreWarnings();
2332
2333         if ( !$haveDiff3 ) {
2334                 wfDebug( "diff3 not found\n" );
2335                 return false;
2336         }
2337
2338         # Make temporary files
2339         $td = wfTempDir();
2340         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
2341         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
2342         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
2343
2344         # NOTE: diff3 issues a warning to stderr if any of the files does not end with
2345         #       a newline character. To avoid this, we normalize the trailing whitespace before
2346         #       creating the diff.
2347
2348         fwrite( $oldtextFile, rtrim( $old ) . "\n" );
2349         fclose( $oldtextFile );
2350         fwrite( $mytextFile, rtrim( $mine ) . "\n" );
2351         fclose( $mytextFile );
2352         fwrite( $yourtextFile, rtrim( $yours ) . "\n" );
2353         fclose( $yourtextFile );
2354
2355         # Check for a conflict
2356         $cmd = Shell::escape( $wgDiff3, '-a', '--overlap-only', $mytextName,
2357                 $oldtextName, $yourtextName );
2358         $handle = popen( $cmd, 'r' );
2359
2360         $mergeAttemptResult = '';
2361         do {
2362                 $data = fread( $handle, 8192 );
2363                 if ( strlen( $data ) == 0 ) {
2364                         break;
2365                 }
2366                 $mergeAttemptResult .= $data;
2367         } while ( true );
2368         pclose( $handle );
2369
2370         $conflict = $mergeAttemptResult !== '';
2371
2372         # Merge differences
2373         $cmd = Shell::escape( $wgDiff3, '-a', '-e', '--merge', $mytextName,
2374                 $oldtextName, $yourtextName );
2375         $handle = popen( $cmd, 'r' );
2376         $result = '';
2377         do {
2378                 $data = fread( $handle, 8192 );
2379                 if ( strlen( $data ) == 0 ) {
2380                         break;
2381                 }
2382                 $result .= $data;
2383         } while ( true );
2384         pclose( $handle );
2385         unlink( $mytextName );
2386         unlink( $oldtextName );
2387         unlink( $yourtextName );
2388
2389         if ( $result === '' && $old !== '' && !$conflict ) {
2390                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
2391                 $conflict = true;
2392         }
2393         return !$conflict;
2394 }
2395
2396 /**
2397  * Returns unified plain-text diff of two texts.
2398  * "Useful" for machine processing of diffs.
2399  *
2400  * @deprecated since 1.25, use DiffEngine/UnifiedDiffFormatter directly
2401  *
2402  * @param string $before The text before the changes.
2403  * @param string $after The text after the changes.
2404  * @param string $params Command-line options for the diff command.
2405  * @return string Unified diff of $before and $after
2406  */
2407 function wfDiff( $before, $after, $params = '-u' ) {
2408         if ( $before == $after ) {
2409                 return '';
2410         }
2411
2412         global $wgDiff;
2413         Wikimedia\suppressWarnings();
2414         $haveDiff = $wgDiff && file_exists( $wgDiff );
2415         Wikimedia\restoreWarnings();
2416
2417         # This check may also protect against code injection in
2418         # case of broken installations.
2419         if ( !$haveDiff ) {
2420                 wfDebug( "diff executable not found\n" );
2421                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
2422                 $format = new UnifiedDiffFormatter();
2423                 return $format->format( $diffs );
2424         }
2425
2426         # Make temporary files
2427         $td = wfTempDir();
2428         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
2429         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
2430
2431         fwrite( $oldtextFile, $before );
2432         fclose( $oldtextFile );
2433         fwrite( $newtextFile, $after );
2434         fclose( $newtextFile );
2435
2436         // Get the diff of the two files
2437         $cmd = "$wgDiff " . $params . ' ' . Shell::escape( $oldtextName, $newtextName );
2438
2439         $h = popen( $cmd, 'r' );
2440         if ( !$h ) {
2441                 unlink( $oldtextName );
2442                 unlink( $newtextName );
2443                 throw new Exception( __METHOD__ . '(): popen() failed' );
2444         }
2445
2446         $diff = '';
2447
2448         do {
2449                 $data = fread( $h, 8192 );
2450                 if ( strlen( $data ) == 0 ) {
2451                         break;
2452                 }
2453                 $diff .= $data;
2454         } while ( true );
2455
2456         // Clean up
2457         pclose( $h );
2458         unlink( $oldtextName );
2459         unlink( $newtextName );
2460
2461         // Kill the --- and +++ lines. They're not useful.
2462         $diff_lines = explode( "\n", $diff );
2463         if ( isset( $diff_lines[0] ) && strpos( $diff_lines[0], '---' ) === 0 ) {
2464                 unset( $diff_lines[0] );
2465         }
2466         if ( isset( $diff_lines[1] ) && strpos( $diff_lines[1], '+++' ) === 0 ) {
2467                 unset( $diff_lines[1] );
2468         }
2469
2470         $diff = implode( "\n", $diff_lines );
2471
2472         return $diff;
2473 }
2474
2475 /**
2476  * This function works like "use VERSION" in Perl, the program will die with a
2477  * backtrace if the current version of PHP is less than the version provided
2478  *
2479  * This is useful for extensions which due to their nature are not kept in sync
2480  * with releases, and might depend on other versions of PHP than the main code
2481  *
2482  * Note: PHP might die due to parsing errors in some cases before it ever
2483  *       manages to call this function, such is life
2484  *
2485  * @see perldoc -f use
2486  *
2487  * @param string|int|float $req_ver The version to check, can be a string, an integer, or a float
2488  *
2489  * @deprecated since 1.30
2490  *
2491  * @throws MWException
2492  */
2493 function wfUsePHP( $req_ver ) {
2494         wfDeprecated( __FUNCTION__, '1.30' );
2495         $php_ver = PHP_VERSION;
2496
2497         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
2498                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
2499         }
2500 }
2501
2502 /**
2503  * This function works like "use VERSION" in Perl except it checks the version
2504  * of MediaWiki, the program will die with a backtrace if the current version
2505  * of MediaWiki is less than the version provided.
2506  *
2507  * This is useful for extensions which due to their nature are not kept in sync
2508  * with releases
2509  *
2510  * Note: Due to the behavior of PHP's version_compare() which is used in this
2511  * function, if you want to allow the 'wmf' development versions add a 'c' (or
2512  * any single letter other than 'a', 'b' or 'p') as a post-fix to your
2513  * targeted version number. For example if you wanted to allow any variation
2514  * of 1.22 use `wfUseMW( '1.22c' )`. Using an 'a' or 'b' instead of 'c' will
2515  * not result in the same comparison due to the internal logic of
2516  * version_compare().
2517  *
2518  * @see perldoc -f use
2519  *
2520  * @deprecated since 1.26, use the "requires" property of extension.json
2521  * @param string|int|float $req_ver The version to check, can be a string, an integer, or a float
2522  * @throws MWException
2523  */
2524 function wfUseMW( $req_ver ) {
2525         global $wgVersion;
2526
2527         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
2528                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
2529         }
2530 }
2531
2532 /**
2533  * Return the final portion of a pathname.
2534  * Reimplemented because PHP5's "basename()" is buggy with multibyte text.
2535  * https://bugs.php.net/bug.php?id=33898
2536  *
2537  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
2538  * We'll consider it so always, as we don't want '\s' in our Unix paths either.
2539  *
2540  * @param string $path
2541  * @param string $suffix String to remove if present
2542  * @return string
2543  */
2544 function wfBaseName( $path, $suffix = '' ) {
2545         if ( $suffix == '' ) {
2546                 $encSuffix = '';
2547         } else {
2548                 $encSuffix = '(?:' . preg_quote( $suffix, '#' ) . ')?';
2549         }
2550
2551         $matches = [];
2552         if ( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2553                 return $matches[1];
2554         } else {
2555                 return '';
2556         }
2557 }
2558
2559 /**
2560  * Generate a relative path name to the given file.
2561  * May explode on non-matching case-insensitive paths,
2562  * funky symlinks, etc.
2563  *
2564  * @param string $path Absolute destination path including target filename
2565  * @param string $from Absolute source path, directory only
2566  * @return string
2567  */
2568 function wfRelativePath( $path, $from ) {
2569         // Normalize mixed input on Windows...
2570         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2571         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2572
2573         // Trim trailing slashes -- fix for drive root
2574         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2575         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2576
2577         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2578         $against = explode( DIRECTORY_SEPARATOR, $from );
2579
2580         if ( $pieces[0] !== $against[0] ) {
2581                 // Non-matching Windows drive letters?
2582                 // Return a full path.
2583                 return $path;
2584         }
2585
2586         // Trim off common prefix
2587         while ( count( $pieces ) && count( $against )
2588                 && $pieces[0] == $against[0] ) {
2589                 array_shift( $pieces );
2590                 array_shift( $against );
2591         }
2592
2593         // relative dots to bump us to the parent
2594         while ( count( $against ) ) {
2595                 array_unshift( $pieces, '..' );
2596                 array_shift( $against );
2597         }
2598
2599         array_push( $pieces, wfBaseName( $path ) );
2600
2601         return implode( DIRECTORY_SEPARATOR, $pieces );
2602 }
2603
2604 /**
2605  * Reset the session id
2606  *
2607  * @deprecated since 1.27, use MediaWiki\Session\SessionManager instead
2608  * @since 1.22
2609  */
2610 function wfResetSessionID() {
2611         wfDeprecated( __FUNCTION__, '1.27' );
2612         $session = SessionManager::getGlobalSession();
2613         $delay = $session->delaySave();
2614
2615         $session->resetId();
2616
2617         // Make sure a session is started, since that's what the old
2618         // wfResetSessionID() did.
2619         if ( session_id() !== $session->getId() ) {
2620                 wfSetupSession( $session->getId() );
2621         }
2622
2623         ScopedCallback::consume( $delay );
2624 }
2625
2626 /**
2627  * Initialise php session
2628  *
2629  * @deprecated since 1.27, use MediaWiki\Session\SessionManager instead.
2630  *  Generally, "using" SessionManager will be calling ->getSessionById() or
2631  *  ::getGlobalSession() (depending on whether you were passing $sessionId
2632  *  here), then calling $session->persist().
2633  * @param bool|string $sessionId
2634  */
2635 function wfSetupSession( $sessionId = false ) {
2636         wfDeprecated( __FUNCTION__, '1.27' );
2637
2638         if ( $sessionId ) {
2639                 session_id( $sessionId );
2640         }
2641
2642         $session = SessionManager::getGlobalSession();
2643         $session->persist();
2644
2645         if ( session_id() !== $session->getId() ) {
2646                 session_id( $session->getId() );
2647         }
2648         Wikimedia\quietCall( 'session_start' );
2649 }
2650
2651 /**
2652  * Get an object from the precompiled serialized directory
2653  *
2654  * @param string $name
2655  * @return mixed The variable on success, false on failure
2656  */
2657 function wfGetPrecompiledData( $name ) {
2658         global $IP;
2659
2660         $file = "$IP/serialized/$name";
2661         if ( file_exists( $file ) ) {
2662                 $blob = file_get_contents( $file );
2663                 if ( $blob ) {
2664                         return unserialize( $blob );
2665                 }
2666         }
2667         return false;
2668 }
2669
2670 /**
2671  * @since 1.32
2672  * @param string[] $data Array with string keys/values to export
2673  * @param string $header
2674  * @return string PHP code
2675  */
2676 function wfMakeStaticArrayFile( array $data, $header = 'Automatically generated' ) {
2677         $format = "\t%s => %s,\n";
2678         $code = "<?php\n"
2679                 . "// " . implode( "\n// ", explode( "\n", $header ) ) . "\n"
2680                 . "return [\n";
2681         foreach ( $data as $key => $value ) {
2682                 $code .= sprintf(
2683                         $format,
2684                         var_export( $key, true ),
2685                         var_export( $value, true )
2686                 );
2687         }
2688         $code .= "];\n";
2689         return $code;
2690 }
2691
2692 /**
2693  * Make a cache key for the local wiki.
2694  *
2695  * @deprecated since 1.30 Call makeKey on a BagOStuff instance
2696  * @param string $args,...
2697  * @return string
2698  */
2699 function wfMemcKey( /*...*/ ) {
2700         return ObjectCache::getLocalClusterInstance()->makeKey( ...func_get_args() );
2701 }
2702
2703 /**
2704  * Make a cache key for a foreign DB.
2705  *
2706  * Must match what wfMemcKey() would produce in context of the foreign wiki.
2707  *
2708  * @param string $db
2709  * @param string $prefix
2710  * @param string $args,...
2711  * @return string
2712  */
2713 function wfForeignMemcKey( $db, $prefix /*...*/ ) {
2714         $args = array_slice( func_get_args(), 2 );
2715         $keyspace = $prefix ? "$db-$prefix" : $db;
2716         return ObjectCache::getLocalClusterInstance()->makeKeyInternal( $keyspace, $args );
2717 }
2718
2719 /**
2720  * Make a cache key with database-agnostic prefix.
2721  *
2722  * Doesn't have a wiki-specific namespace. Uses a generic 'global' prefix
2723  * instead. Must have a prefix as otherwise keys that use a database name
2724  * in the first segment will clash with wfMemcKey/wfForeignMemcKey.
2725  *
2726  * @deprecated since 1.30 Call makeGlobalKey on a BagOStuff instance
2727  * @since 1.26
2728  * @param string $args,...
2729  * @return string
2730  */
2731 function wfGlobalCacheKey( /*...*/ ) {
2732         return ObjectCache::getLocalClusterInstance()->makeGlobalKey( ...func_get_args() );
2733 }
2734
2735 /**
2736  * Get an ASCII string identifying this wiki
2737  * This is used as a prefix in memcached keys
2738  *
2739  * @return string
2740  */
2741 function wfWikiID() {
2742         global $wgDBprefix, $wgDBname;
2743         if ( $wgDBprefix ) {
2744                 return "$wgDBname-$wgDBprefix";
2745         } else {
2746                 return $wgDBname;
2747         }
2748 }
2749
2750 /**
2751  * Split a wiki ID into DB name and table prefix
2752  *
2753  * @param string $wiki
2754  *
2755  * @return array
2756  */
2757 function wfSplitWikiID( $wiki ) {
2758         $bits = explode( '-', $wiki, 2 );
2759         if ( count( $bits ) < 2 ) {
2760                 $bits[] = '';
2761         }
2762         return $bits;
2763 }
2764
2765 /**
2766  * Get a Database object.
2767  *
2768  * @param int $db Index of the connection to get. May be DB_MASTER for the
2769  *            master (for write queries), DB_REPLICA for potentially lagged read
2770  *            queries, or an integer >= 0 for a particular server.
2771  *
2772  * @param string|string[] $groups Query groups. An array of group names that this query
2773  *                belongs to. May contain a single string if the query is only
2774  *                in one group.
2775  *
2776  * @param string|bool $wiki The wiki ID, or false for the current wiki
2777  *
2778  * Note: multiple calls to wfGetDB(DB_REPLICA) during the course of one request
2779  * will always return the same object, unless the underlying connection or load
2780  * balancer is manually destroyed.
2781  *
2782  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
2783  * updater to ensure that a proper database is being updated.
2784  *
2785  * @todo Replace calls to wfGetDB with calls to LoadBalancer::getConnection()
2786  *       on an injected instance of LoadBalancer.
2787  *
2788  * @return \Wikimedia\Rdbms\Database
2789  */
2790 function wfGetDB( $db, $groups = [], $wiki = false ) {
2791         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
2792 }
2793
2794 /**
2795  * Get a load balancer object.
2796  *
2797  * @deprecated since 1.27, use MediaWikiServices::getDBLoadBalancer()
2798  *              or MediaWikiServices::getDBLoadBalancerFactory() instead.
2799  *
2800  * @param string|bool $wiki Wiki ID, or false for the current wiki
2801  * @return \Wikimedia\Rdbms\LoadBalancer
2802  */
2803 function wfGetLB( $wiki = false ) {
2804         if ( $wiki === false ) {
2805                 return MediaWikiServices::getInstance()->getDBLoadBalancer();
2806         } else {
2807                 $factory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
2808                 return $factory->getMainLB( $wiki );
2809         }
2810 }
2811
2812 /**
2813  * Get the load balancer factory object
2814  *
2815  * @deprecated since 1.27, use MediaWikiServices::getDBLoadBalancerFactory() instead.
2816  *
2817  * @return \Wikimedia\Rdbms\LBFactory
2818  */
2819 function wfGetLBFactory() {
2820         return MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
2821 }
2822
2823 /**
2824  * Find a file.
2825  * Shortcut for RepoGroup::singleton()->findFile()
2826  *
2827  * @param string|Title $title String or Title object
2828  * @param array $options Associative array of options (see RepoGroup::findFile)
2829  * @return File|bool File, or false if the file does not exist
2830  */
2831 function wfFindFile( $title, $options = [] ) {
2832         return RepoGroup::singleton()->findFile( $title, $options );
2833 }
2834
2835 /**
2836  * Get an object referring to a locally registered file.
2837  * Returns a valid placeholder object if the file does not exist.
2838  *
2839  * @param Title|string $title
2840  * @return LocalFile|null A File, or null if passed an invalid Title
2841  */
2842 function wfLocalFile( $title ) {
2843         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
2844 }
2845
2846 /**
2847  * Should low-performance queries be disabled?
2848  *
2849  * @return bool
2850  * @codeCoverageIgnore
2851  */
2852 function wfQueriesMustScale() {
2853         global $wgMiserMode;
2854         return $wgMiserMode
2855                 || ( SiteStats::pages() > 100000
2856                 && SiteStats::edits() > 1000000
2857                 && SiteStats::users() > 10000 );
2858 }
2859
2860 /**
2861  * Get the path to a specified script file, respecting file
2862  * extensions; this is a wrapper around $wgScriptPath etc.
2863  * except for 'index' and 'load' which use $wgScript/$wgLoadScript
2864  *
2865  * @param string $script Script filename, sans extension
2866  * @return string
2867  */
2868 function wfScript( $script = 'index' ) {
2869         global $wgScriptPath, $wgScript, $wgLoadScript;
2870         if ( $script === 'index' ) {
2871                 return $wgScript;
2872         } elseif ( $script === 'load' ) {
2873                 return $wgLoadScript;
2874         } else {
2875                 return "{$wgScriptPath}/{$script}.php";
2876         }
2877 }
2878
2879 /**
2880  * Get the script URL.
2881  *
2882  * @return string Script URL
2883  */
2884 function wfGetScriptUrl() {
2885         if ( isset( $_SERVER['SCRIPT_NAME'] ) ) {
2886                 /* as it was called, minus the query string.
2887                  *
2888                  * Some sites use Apache rewrite rules to handle subdomains,
2889                  * and have PHP set up in a weird way that causes PHP_SELF
2890                  * to contain the rewritten URL instead of the one that the
2891                  * outside world sees.
2892                  *
2893                  * If in this mode, use SCRIPT_URL instead, which mod_rewrite
2894                  * provides containing the "before" URL.
2895                  */
2896                 return $_SERVER['SCRIPT_NAME'];
2897         } else {
2898                 return $_SERVER['URL'];
2899         }
2900 }
2901
2902 /**
2903  * Convenience function converts boolean values into "true"
2904  * or "false" (string) values
2905  *
2906  * @param bool $value
2907  * @return string
2908  */
2909 function wfBoolToStr( $value ) {
2910         return $value ? 'true' : 'false';
2911 }
2912
2913 /**
2914  * Get a platform-independent path to the null file, e.g. /dev/null
2915  *
2916  * @return string
2917  */
2918 function wfGetNull() {
2919         return wfIsWindows() ? 'NUL' : '/dev/null';
2920 }
2921
2922 /**
2923  * Waits for the replica DBs to catch up to the master position
2924  *
2925  * Use this when updating very large numbers of rows, as in maintenance scripts,
2926  * to avoid causing too much lag. Of course, this is a no-op if there are no replica DBs.
2927  *
2928  * By default this waits on the main DB cluster of the current wiki.
2929  * If $cluster is set to "*" it will wait on all DB clusters, including
2930  * external ones. If the lag being waiting on is caused by the code that
2931  * does this check, it makes since to use $ifWritesSince, particularly if
2932  * cluster is "*", to avoid excess overhead.
2933  *
2934  * Never call this function after a big DB write that is still in a transaction.
2935  * This only makes sense after the possible lag inducing changes were committed.
2936  *
2937  * @param float|null $ifWritesSince Only wait if writes were done since this UNIX timestamp
2938  * @param string|bool $wiki Wiki identifier accepted by wfGetLB
2939  * @param string|bool $cluster Cluster name accepted by LBFactory. Default: false.
2940  * @param int|null $timeout Max wait time. Default: 1 day (cli), ~10 seconds (web)
2941  * @return bool Success (able to connect and no timeouts reached)
2942  * @deprecated since 1.27 Use LBFactory::waitForReplication
2943  */
2944 function wfWaitForSlaves(
2945         $ifWritesSince = null, $wiki = false, $cluster = false, $timeout = null
2946 ) {
2947         if ( $timeout === null ) {
2948                 $timeout = wfIsCLI() ? 60 : 10;
2949         }
2950
2951         if ( $cluster === '*' ) {
2952                 $cluster = false;
2953                 $wiki = false;
2954         } elseif ( $wiki === false ) {
2955                 $wiki = wfWikiID();
2956         }
2957
2958         try {
2959                 $lbFactory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
2960                 $lbFactory->waitForReplication( [
2961                         'wiki' => $wiki,
2962                         'cluster' => $cluster,
2963                         'timeout' => $timeout,
2964                         // B/C: first argument used to be "max seconds of lag"; ignore such values
2965                         'ifWritesSince' => ( $ifWritesSince > 1e9 ) ? $ifWritesSince : null
2966                 ] );
2967         } catch ( DBReplicationWaitError $e ) {
2968                 return false;
2969         }
2970
2971         return true;
2972 }
2973
2974 /**
2975  * Count down from $seconds to zero on the terminal, with a one-second pause
2976  * between showing each number. For use in command-line scripts.
2977  *
2978  * @deprecated since 1.31, use Maintenance::countDown()
2979  *
2980  * @codeCoverageIgnore
2981  * @param int $seconds
2982  */
2983 function wfCountDown( $seconds ) {
2984         wfDeprecated( __FUNCTION__, '1.31' );
2985         for ( $i = $seconds; $i >= 0; $i-- ) {
2986                 if ( $i != $seconds ) {
2987                         echo str_repeat( "\x08", strlen( $i + 1 ) );
2988                 }
2989                 echo $i;
2990                 flush();
2991                 if ( $i ) {
2992                         sleep( 1 );
2993                 }
2994         }
2995         echo "\n";
2996 }
2997
2998 /**
2999  * Replace all invalid characters with '-'.
3000  * Additional characters can be defined in $wgIllegalFileChars (see T22489).
3001  * By default, $wgIllegalFileChars includes ':', '/', '\'.
3002  *
3003  * @param string $name Filename to process
3004  * @return string
3005  */
3006 function wfStripIllegalFilenameChars( $name ) {
3007         global $wgIllegalFileChars;
3008         $illegalFileChars = $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '';
3009         $name = preg_replace(
3010                 "/[^" . Title::legalChars() . "]" . $illegalFileChars . "/",
3011                 '-',
3012                 $name
3013         );
3014         // $wgIllegalFileChars may not include '/' and '\', so we still need to do this
3015         $name = wfBaseName( $name );
3016         return $name;
3017 }
3018
3019 /**
3020  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit
3021  *
3022  * @return int Resulting value of the memory limit.
3023  */
3024 function wfMemoryLimit() {
3025         global $wgMemoryLimit;
3026         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3027         if ( $memlimit != -1 ) {
3028                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3029                 if ( $conflimit == -1 ) {
3030                         wfDebug( "Removing PHP's memory limit\n" );
3031                         Wikimedia\suppressWarnings();
3032                         ini_set( 'memory_limit', $conflimit );
3033                         Wikimedia\restoreWarnings();
3034                         return $conflimit;
3035                 } elseif ( $conflimit > $memlimit ) {
3036                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3037                         Wikimedia\suppressWarnings();
3038                         ini_set( 'memory_limit', $conflimit );
3039                         Wikimedia\restoreWarnings();
3040                         return $conflimit;
3041                 }
3042         }
3043         return $memlimit;
3044 }
3045
3046 /**
3047  * Set PHP's time limit to the larger of php.ini or $wgTransactionalTimeLimit
3048  *
3049  * @return int Prior time limit
3050  * @since 1.26
3051  */
3052 function wfTransactionalTimeLimit() {
3053         global $wgTransactionalTimeLimit;
3054
3055         $timeLimit = ini_get( 'max_execution_time' );
3056         // Note that CLI scripts use 0
3057         if ( $timeLimit > 0 && $wgTransactionalTimeLimit > $timeLimit ) {
3058                 set_time_limit( $wgTransactionalTimeLimit );
3059         }
3060
3061         ignore_user_abort( true ); // ignore client disconnects
3062
3063         return $timeLimit;
3064 }
3065
3066 /**
3067  * Converts shorthand byte notation to integer form
3068  *
3069  * @param string $string
3070  * @param int $default Returned if $string is empty
3071  * @return int
3072  */
3073 function wfShorthandToInteger( $string = '', $default = -1 ) {
3074         $string = trim( $string );
3075         if ( $string === '' ) {
3076                 return $default;
3077         }
3078         $last = $string[strlen( $string ) - 1];
3079         $val = intval( $string );
3080         switch ( $last ) {
3081                 case 'g':
3082                 case 'G':
3083                         $val *= 1024;
3084                         // break intentionally missing
3085                 case 'm':
3086                 case 'M':
3087                         $val *= 1024;
3088                         // break intentionally missing
3089                 case 'k':
3090                 case 'K':
3091                         $val *= 1024;
3092         }
3093
3094         return $val;
3095 }
3096
3097 /**
3098  * Get the normalised IETF language tag
3099  * See unit test for examples.
3100  * See mediawiki.language.bcp47 for the JavaScript implementation.
3101  *
3102  * @deprecated since 1.31, use LanguageCode::bcp47() directly.
3103  *
3104  * @param string $code The language code.
3105  * @return string The language code which complying with BCP 47 standards.
3106  */
3107 function wfBCP47( $code ) {
3108         wfDeprecated( __METHOD__, '1.31' );
3109         return LanguageCode::bcp47( $code );
3110 }
3111
3112 /**
3113  * Get a specific cache object.
3114  *
3115  * @param int|string $cacheType A CACHE_* constants, or other key in $wgObjectCaches
3116  * @return BagOStuff
3117  */
3118 function wfGetCache( $cacheType ) {
3119         return ObjectCache::getInstance( $cacheType );
3120 }
3121
3122 /**
3123  * Get the main cache object
3124  *
3125  * @return BagOStuff
3126  */
3127 function wfGetMainCache() {
3128         global $wgMainCacheType;
3129         return ObjectCache::getInstance( $wgMainCacheType );
3130 }
3131
3132 /**
3133  * Get the cache object used by the message cache
3134  *
3135  * @return BagOStuff
3136  */
3137 function wfGetMessageCacheStorage() {
3138         global $wgMessageCacheType;
3139         return ObjectCache::getInstance( $wgMessageCacheType );
3140 }
3141
3142 /**
3143  * Call hook functions defined in $wgHooks
3144  *
3145  * @param string $event Event name
3146  * @param array $args Parameters passed to hook functions
3147  * @param string|null $deprecatedVersion Optionally mark hook as deprecated with version number
3148  *
3149  * @return bool True if no handler aborted the hook
3150  * @deprecated since 1.25 - use Hooks::run
3151  */
3152 function wfRunHooks( $event, array $args = [], $deprecatedVersion = null ) {
3153         wfDeprecated( __METHOD__, '1.25' );
3154         return Hooks::run( $event, $args, $deprecatedVersion );
3155 }
3156
3157 /**
3158  * Wrapper around php's unpack.
3159  *
3160  * @param string $format The format string (See php's docs)
3161  * @param string $data A binary string of binary data
3162  * @param int|bool $length The minimum length of $data or false. This is to
3163  *      prevent reading beyond the end of $data. false to disable the check.
3164  *
3165  * Also be careful when using this function to read unsigned 32 bit integer
3166  * because php might make it negative.
3167  *
3168  * @throws MWException If $data not long enough, or if unpack fails
3169  * @return array Associative array of the extracted data
3170  */
3171 function wfUnpack( $format, $data, $length = false ) {
3172         if ( $length !== false ) {
3173                 $realLen = strlen( $data );
3174                 if ( $realLen < $length ) {
3175                         throw new MWException( "Tried to use wfUnpack on a "
3176                                 . "string of length $realLen, but needed one "
3177                                 . "of at least length $length."
3178                         );
3179                 }
3180         }
3181
3182         Wikimedia\suppressWarnings();
3183         $result = unpack( $format, $data );
3184         Wikimedia\restoreWarnings();
3185
3186         if ( $result === false ) {
3187                 // If it cannot extract the packed data.
3188                 throw new MWException( "unpack could not unpack binary data" );
3189         }
3190         return $result;
3191 }
3192
3193 /**
3194  * Determine if an image exists on the 'bad image list'.
3195  *
3196  * The format of MediaWiki:Bad_image_list is as follows:
3197  *    * Only list items (lines starting with "*") are considered
3198  *    * The first link on a line must be a link to a bad image
3199  *    * Any subsequent links on the same line are considered to be exceptions,
3200  *      i.e. articles where the image may occur inline.
3201  *
3202  * @param string $name The image name to check
3203  * @param Title|bool $contextTitle The page on which the image occurs, if known
3204  * @param string|null $blacklist Wikitext of a file blacklist
3205  * @return bool
3206  */
3207 function wfIsBadImage( $name, $contextTitle = false, $blacklist = null ) {
3208         # Handle redirects; callers almost always hit wfFindFile() anyway,
3209         # so just use that method because it has a fast process cache.
3210         $file = wfFindFile( $name ); // get the final name
3211         $name = $file ? $file->getTitle()->getDBkey() : $name;
3212
3213         # Run the extension hook
3214         $bad = false;
3215         if ( !Hooks::run( 'BadImage', [ $name, &$bad ] ) ) {
3216                 return (bool)$bad;
3217         }
3218
3219         $cache = ObjectCache::getLocalServerInstance( 'hash' );
3220         $key = $cache->makeKey(
3221                 'bad-image-list', ( $blacklist === null ) ? 'default' : md5( $blacklist )
3222         );
3223         $badImages = $cache->get( $key );
3224
3225         if ( $badImages === false ) { // cache miss
3226                 if ( $blacklist === null ) {
3227                         $blacklist = wfMessage( 'bad_image_list' )->inContentLanguage()->plain(); // site list
3228                 }
3229                 # Build the list now
3230                 $badImages = [];
3231                 $lines = explode( "\n", $blacklist );
3232                 foreach ( $lines as $line ) {
3233                         # List items only
3234                         if ( substr( $line, 0, 1 ) !== '*' ) {
3235                                 continue;
3236                         }
3237
3238                         # Find all links
3239                         $m = [];
3240                         if ( !preg_match_all( '/\[\[:?(.*?)\]\]/', $line, $m ) ) {
3241                                 continue;
3242                         }
3243
3244                         $exceptions = [];
3245                         $imageDBkey = false;
3246                         foreach ( $m[1] as $i => $titleText ) {
3247                                 $title = Title::newFromText( $titleText );
3248                                 if ( !is_null( $title ) ) {
3249                                         if ( $i == 0 ) {
3250                                                 $imageDBkey = $title->getDBkey();
3251                                         } else {
3252                                                 $exceptions[$title->getPrefixedDBkey()] = true;
3253                                         }
3254                                 }
3255                         }
3256
3257                         if ( $imageDBkey !== false ) {
3258                                 $badImages[$imageDBkey] = $exceptions;
3259                         }
3260                 }
3261                 $cache->set( $key, $badImages, 60 );
3262         }
3263
3264         $contextKey = $contextTitle ? $contextTitle->getPrefixedDBkey() : false;
3265         $bad = isset( $badImages[$name] ) && !isset( $badImages[$name][$contextKey] );
3266
3267         return $bad;
3268 }
3269
3270 /**
3271  * Determine whether the client at a given source IP is likely to be able to
3272  * access the wiki via HTTPS.
3273  *
3274  * @param string $ip The IPv4/6 address in the normal human-readable form
3275  * @return bool
3276  */
3277 function wfCanIPUseHTTPS( $ip ) {
3278         $canDo = true;
3279         Hooks::run( 'CanIPUseHTTPS', [ $ip, &$canDo ] );
3280         return !!$canDo;
3281 }
3282
3283 /**
3284  * Determine input string is represents as infinity
3285  *
3286  * @param string $str The string to determine
3287  * @return bool
3288  * @since 1.25
3289  */
3290 function wfIsInfinity( $str ) {
3291         // These are hardcoded elsewhere in MediaWiki (e.g. mediawiki.special.block.js).
3292         $infinityValues = [ 'infinite', 'indefinite', 'infinity', 'never' ];
3293         return in_array( $str, $infinityValues );
3294 }
3295
3296 /**
3297  * Returns true if these thumbnail parameters match one that MediaWiki
3298  * requests from file description pages and/or parser output.
3299  *
3300  * $params is considered non-standard if they involve a non-standard
3301  * width or any non-default parameters aside from width and page number.
3302  * The number of possible files with standard parameters is far less than
3303  * that of all combinations; rate-limiting for them can thus be more generious.
3304  *
3305  * @param File $file
3306  * @param array $params
3307  * @return bool
3308  * @since 1.24 Moved from thumb.php to GlobalFunctions in 1.25
3309  */
3310 function wfThumbIsStandard( File $file, array $params ) {
3311         global $wgThumbLimits, $wgImageLimits, $wgResponsiveImages;
3312
3313         $multipliers = [ 1 ];
3314         if ( $wgResponsiveImages ) {
3315                 // These available sizes are hardcoded currently elsewhere in MediaWiki.
3316                 // @see Linker::processResponsiveImages
3317                 $multipliers[] = 1.5;
3318                 $multipliers[] = 2;
3319         }
3320
3321         $handler = $file->getHandler();
3322         if ( !$handler || !isset( $params['width'] ) ) {
3323                 return false;
3324         }
3325
3326         $basicParams = [];
3327         if ( isset( $params['page'] ) ) {
3328                 $basicParams['page'] = $params['page'];
3329         }
3330
3331         $thumbLimits = [];
3332         $imageLimits = [];
3333         // Expand limits to account for multipliers
3334         foreach ( $multipliers as $multiplier ) {
3335                 $thumbLimits = array_merge( $thumbLimits, array_map(
3336                         function ( $width ) use ( $multiplier ) {
3337                                 return round( $width * $multiplier );
3338                         }, $wgThumbLimits )
3339                 );
3340                 $imageLimits = array_merge( $imageLimits, array_map(
3341                         function ( $pair ) use ( $multiplier ) {
3342                                 return [
3343                                         round( $pair[0] * $multiplier ),
3344                                         round( $pair[1] * $multiplier ),
3345                                 ];
3346                         }, $wgImageLimits )
3347                 );
3348         }
3349
3350         // Check if the width matches one of $wgThumbLimits
3351         if ( in_array( $params['width'], $thumbLimits ) ) {
3352                 $normalParams = $basicParams + [ 'width' => $params['width'] ];
3353                 // Append any default values to the map (e.g. "lossy", "lossless", ...)
3354                 $handler->normaliseParams( $file, $normalParams );
3355         } else {
3356                 // If not, then check if the width matchs one of $wgImageLimits
3357                 $match = false;
3358                 foreach ( $imageLimits as $pair ) {
3359                         $normalParams = $basicParams + [ 'width' => $pair[0], 'height' => $pair[1] ];
3360                         // Decide whether the thumbnail should be scaled on width or height.
3361                         // Also append any default values to the map (e.g. "lossy", "lossless", ...)
3362                         $handler->normaliseParams( $file, $normalParams );
3363                         // Check if this standard thumbnail size maps to the given width
3364                         if ( $normalParams['width'] == $params['width'] ) {
3365                                 $match = true;
3366                                 break;
3367                         }
3368                 }
3369                 if ( !$match ) {
3370                         return false; // not standard for description pages
3371                 }
3372         }
3373
3374         // Check that the given values for non-page, non-width, params are just defaults
3375         foreach ( $params as $key => $value ) {
3376                 if ( !isset( $normalParams[$key] ) || $normalParams[$key] != $value ) {
3377                         return false;
3378                 }
3379         }
3380
3381         return true;
3382 }
3383
3384 /**
3385  * Merges two (possibly) 2 dimensional arrays into the target array ($baseArray).
3386  *
3387  * Values that exist in both values will be combined with += (all values of the array
3388  * of $newValues will be added to the values of the array of $baseArray, while values,
3389  * that exists in both, the value of $baseArray will be used).
3390  *
3391  * @param array $baseArray The array where you want to add the values of $newValues to
3392  * @param array $newValues An array with new values
3393  * @return array The combined array
3394  * @since 1.26
3395  */
3396 function wfArrayPlus2d( array $baseArray, array $newValues ) {
3397         // First merge items that are in both arrays
3398         foreach ( $baseArray as $name => &$groupVal ) {
3399                 if ( isset( $newValues[$name] ) ) {
3400                         $groupVal += $newValues[$name];
3401                 }
3402         }
3403         // Now add items that didn't exist yet
3404         $baseArray += $newValues;
3405
3406         return $baseArray;
3407 }
3408
3409 /**
3410  * Get system resource usage of current request context.
3411  * Invokes the getrusage(2) system call, requesting RUSAGE_SELF if on PHP5
3412  * or RUSAGE_THREAD if on HHVM. Returns false if getrusage is not available.
3413  *
3414  * @since 1.24
3415  * @return array|bool Resource usage data or false if no data available.
3416  */
3417 function wfGetRusage() {
3418         if ( !function_exists( 'getrusage' ) ) {
3419                 return false;
3420         } elseif ( defined( 'HHVM_VERSION' ) && PHP_OS === 'Linux' ) {
3421                 return getrusage( 2 /* RUSAGE_THREAD */ );
3422         } else {
3423                 return getrusage( 0 /* RUSAGE_SELF */ );
3424         }
3425 }