includes/GlobalFunctions.php

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