includes/GlobalFunctions.php

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