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 // Hide compatibility functions from Doxygen
  28 /// @cond
  29
  30 /**
  31  * Compatibility functions
  32  *
  33  * We support PHP 5.3.2 and up.
  34  * Re-implementations of newer functions or functions in non-standard
  35  * PHP extensions may be included here.
  36  */
  37
  38 if ( !function_exists( 'iconv' ) ) {
  39         /**
  40          * @codeCoverageIgnore
  41          * @return string
  42          */
  43         function iconv( $from, $to, $string ) {
  44                 return Fallback::iconv( $from, $to, $string );
  45         }
  46 }
  47
  48 if ( !function_exists( 'mb_substr' ) ) {
  49         /**
  50          * @codeCoverageIgnore
  51          * @return string
  52          */
  53         function mb_substr( $str, $start, $count = 'end' ) {
  54                 return Fallback::mb_substr( $str, $start, $count );
  55         }
  56
  57         /**
  58          * @codeCoverageIgnore
  59          * @return int
  60          */
  61         function mb_substr_split_unicode( $str, $splitPos ) {
  62                 return Fallback::mb_substr_split_unicode( $str, $splitPos );
  63         }
  64 }
  65
  66 if ( !function_exists( 'mb_strlen' ) ) {
  67         /**
  68          * @codeCoverageIgnore
  69          * @return int
  70          */
  71         function mb_strlen( $str, $enc = '' ) {
  72                 return Fallback::mb_strlen( $str, $enc );
  73         }
  74 }
  75
  76 if ( !function_exists( 'mb_strpos' ) ) {
  77         /**
  78          * @codeCoverageIgnore
  79          * @return int
  80          */
  81         function mb_strpos( $haystack, $needle, $offset = 0, $encoding = '' ) {
  82                 return Fallback::mb_strpos( $haystack, $needle, $offset, $encoding );
  83         }
  84
  85 }
  86
  87 if ( !function_exists( 'mb_strrpos' ) ) {
  88         /**
  89          * @codeCoverageIgnore
  90          * @return int
  91          */
  92         function mb_strrpos( $haystack, $needle, $offset = 0, $encoding = '' ) {
  93                 return Fallback::mb_strrpos( $haystack, $needle, $offset, $encoding );
  94         }
  95 }
  96 /// @endcond
  97
  98 /**
  99  * Like array_diff( $a, $b ) except that it works with two-dimensional arrays.
 100  * @param $a array
 101  * @param $b array
 102  * @return array
 103  */
 104 function wfArrayDiff2( $a, $b ) {
 105         return array_udiff( $a, $b, 'wfArrayDiff2_cmp' );
 106 }
 107
 108 /**
 109  * @param $a
 110  * @param $b
 111  * @return int
 112  */
 113 function wfArrayDiff2_cmp( $a, $b ) {
 114         if ( !is_array( $a ) ) {
 115                 return strcmp( $a, $b );
 116         } elseif ( count( $a ) !== count( $b ) ) {
 117                 return count( $a ) < count( $b ) ? -1 : 1;
 118         } else {
 119                 reset( $a );
 120                 reset( $b );
 121                 while ( ( list( , $valueA ) = each( $a ) ) && ( list( , $valueB ) = each( $b ) ) ) {
 122                         $cmp = strcmp( $valueA, $valueB );
 123                         if ( $cmp !== 0 ) {
 124                                 return $cmp;
 125                         }
 126                 }
 127                 return 0;
 128         }
 129 }
 130
 131 /**
 132  * Array lookup
 133  * Returns an array where the values in the first array are replaced by the
 134  * values in the second array with the corresponding keys
 135  *
 136  * @param $a Array
 137  * @param $b Array
 138  * @return array
 139  */
 140 function wfArrayLookup( $a, $b ) {
 141         return array_flip( array_intersect( array_flip( $a ), array_keys( $b ) ) );
 142 }
 143
 144 /**
 145  * Appends to second array if $value differs from that in $default
 146  *
 147  * @param $key String|Int
 148  * @param $value Mixed
 149  * @param $default Mixed
 150  * @param array $changed to alter
 151  * @throws MWException
 152  */
 153 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
 154         if ( is_null( $changed ) ) {
 155                 throw new MWException( 'GlobalFunctions::wfAppendToArrayIfNotDefault got null' );
 156         }
 157         if ( $default[$key] !== $value ) {
 158                 $changed[$key] = $value;
 159         }
 160 }
 161
 162 /**
 163  * Backwards array plus for people who haven't bothered to read the PHP manual
 164  * XXX: will not darn your socks for you.
 165  *
 166  * @param $array1 Array
 167  * @param [$array2, [...]] Arrays
 168  * @return Array
 169  */
 170 function wfArrayMerge( $array1/* ... */ ) {
 171         $args = func_get_args();
 172         $args = array_reverse( $args, true );
 173         $out = array();
 174         foreach ( $args as $arg ) {
 175                 $out += $arg;
 176         }
 177         return $out;
 178 }
 179
 180 /**
 181  * Merge arrays in the style of getUserPermissionsErrors, with duplicate removal
 182  * e.g.
 183  *      wfMergeErrorArrays(
 184  *              array( array( 'x' ) ),
 185  *              array( array( 'x', '2' ) ),
 186  *              array( array( 'x' ) ),
 187  *              array( array( 'y' ) )
 188  *      );
 189  * returns:
 190  *              array(
 191  *              array( 'x', '2' ),
 192  *              array( 'x' ),
 193  *              array( 'y' )
 194  *      )
 195  * @param varargs
 196  * @return Array
 197  */
 198 function wfMergeErrorArrays( /*...*/ ) {
 199         $args = func_get_args();
 200         $out = array();
 201         foreach ( $args as $errors ) {
 202                 foreach ( $errors as $params ) {
 203                         # @todo FIXME: Sometimes get nested arrays for $params,
 204                         # which leads to E_NOTICEs
 205                         $spec = implode( "\t", $params );
 206                         $out[$spec] = $params;
 207                 }
 208         }
 209         return array_values( $out );
 210 }
 211
 212 /**
 213  * Insert array into another array after the specified *KEY*
 214  *
 215  * @param array $array The array.
 216  * @param array $insert The array to insert.
 217  * @param $after Mixed: The key to insert after
 218  * @return Array
 219  */
 220 function wfArrayInsertAfter( array $array, array $insert, $after ) {
 221         // Find the offset of the element to insert after.
 222         $keys = array_keys( $array );
 223         $offsetByKey = array_flip( $keys );
 224
 225         $offset = $offsetByKey[$after];
 226
 227         // Insert at the specified offset
 228         $before = array_slice( $array, 0, $offset + 1, true );
 229         $after = array_slice( $array, $offset + 1, count( $array ) - $offset, true );
 230
 231         $output = $before + $insert + $after;
 232
 233         return $output;
 234 }
 235
 236 /**
 237  * Recursively converts the parameter (an object) to an array with the same data
 238  *
 239  * @param $objOrArray Object|Array
 240  * @param $recursive Bool
 241  * @return Array
 242  */
 243 function wfObjectToArray( $objOrArray, $recursive = true ) {
 244         $array = array();
 245         if ( is_object( $objOrArray ) ) {
 246                 $objOrArray = get_object_vars( $objOrArray );
 247         }
 248         foreach ( $objOrArray as $key => $value ) {
 249                 if ( $recursive && ( is_object( $value ) || is_array( $value ) ) ) {
 250                         $value = wfObjectToArray( $value );
 251                 }
 252
 253                 $array[$key] = $value;
 254         }
 255
 256         return $array;
 257 }
 258
 259 /**
 260  * Get a random decimal value between 0 and 1, in a way
 261  * not likely to give duplicate values for any realistic
 262  * number of articles.
 263  *
 264  * @return string
 265  */
 266 function wfRandom() {
 267         # The maximum random value is "only" 2^31-1, so get two random
 268         # values to reduce the chance of dupes
 269         $max = mt_getrandmax() + 1;
 270         $rand = number_format( ( mt_rand() * $max + mt_rand() )
 271                 / $max / $max, 12, '.', '' );
 272         return $rand;
 273 }
 274
 275 /**
 276  * Get a random string containing a number of pseudo-random hex
 277  * characters.
 278  * @note This is not secure, if you are trying to generate some sort
 279  *       of token please use MWCryptRand instead.
 280  *
 281  * @param int $length The length of the string to generate
 282  * @return String
 283  * @since 1.20
 284  */
 285 function wfRandomString( $length = 32 ) {
 286         $str = '';
 287         for ( $n = 0; $n < $length; $n += 7 ) {
 288                 $str .= sprintf( '%07x', mt_rand() & 0xfffffff );
 289         }
 290         return substr( $str, 0, $length );
 291 }
 292
 293 /**
 294  * We want some things to be included as literal characters in our title URLs
 295  * for prettiness, which urlencode encodes by default.  According to RFC 1738,
 296  * all of the following should be safe:
 297  *
 298  * ;:@&=$-_.+!*'(),
 299  *
 300  * But + is not safe because it's used to indicate a space; &= are only safe in
 301  * paths and not in queries (and we don't distinguish here); ' seems kind of
 302  * scary; and urlencode() doesn't touch -_. to begin with.  Plus, although /
 303  * is reserved, we don't care.  So the list we unescape is:
 304  *
 305  * ;:@$!*(),/
 306  *
 307  * However, IIS7 redirects fail when the url contains a colon (Bug 22709),
 308  * so no fancy : for IIS7.
 309  *
 310  * %2F in the page titles seems to fatally break for some reason.
 311  *
 312  * @param $s String:
 313  * @return string
 314  */
 315 function wfUrlencode( $s ) {
 316         static $needle;
 317         if ( is_null( $s ) ) {
 318                 $needle = null;
 319                 return '';
 320         }
 321
 322         if ( is_null( $needle ) ) {
 323                 $needle = array( '%3B', '%40', '%24', '%21', '%2A', '%28', '%29', '%2C', '%2F' );
 324                 if ( !isset( $_SERVER['SERVER_SOFTWARE'] ) || ( strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/7' ) === false ) ) {
 325                         $needle[] = '%3A';
 326                 }
 327         }
 328
 329         $s = urlencode( $s );
 330         $s = str_ireplace(
 331                 $needle,
 332                 array( ';', '@', '$', '!', '*', '(', ')', ',', '/', ':' ),
 333                 $s
 334         );
 335
 336         return $s;
 337 }
 338
 339 /**
 340  * This function takes two arrays as input, and returns a CGI-style string, e.g.
 341  * "days=7&limit=100". Options in the first array override options in the second.
 342  * Options set to null or false will not be output.
 343  *
 344  * @param array $array1 ( String|Array )
 345  * @param array $array2 ( String|Array )
 346  * @param $prefix String
 347  * @return String
 348  */
 349 function wfArrayToCgi( $array1, $array2 = null, $prefix = '' ) {
 350         if ( !is_null( $array2 ) ) {
 351                 $array1 = $array1 + $array2;
 352         }
 353
 354         $cgi = '';
 355         foreach ( $array1 as $key => $value ) {
 356                 if ( !is_null( $value ) && $value !== false ) {
 357                         if ( $cgi != '' ) {
 358                                 $cgi .= '&';
 359                         }
 360                         if ( $prefix !== '' ) {
 361                                 $key = $prefix . "[$key]";
 362                         }
 363                         if ( is_array( $value ) ) {
 364                                 $firstTime = true;
 365                                 foreach ( $value as $k => $v ) {
 366                                         $cgi .= $firstTime ? '' : '&';
 367                                         if ( is_array( $v ) ) {
 368                                                 $cgi .= wfArrayToCgi( $v, null, $key . "[$k]" );
 369                                         } else {
 370                                                 $cgi .= urlencode( $key . "[$k]" ) . '=' . urlencode( $v );
 371                                         }
 372                                         $firstTime = false;
 373                                 }
 374                         } else {
 375                                 if ( is_object( $value ) ) {
 376                                         $value = $value->__toString();
 377                                 }
 378                                 $cgi .= urlencode( $key ) . '=' . urlencode( $value );
 379                         }
 380                 }
 381         }
 382         return $cgi;
 383 }
 384
 385 /**
 386  * This is the logical opposite of wfArrayToCgi(): it accepts a query string as
 387  * its argument and returns the same string in array form.  This allows compatibility
 388  * with legacy functions that accept raw query strings instead of nice
 389  * arrays.  Of course, keys and values are urldecode()d.
 390  *
 391  * @param string $query query string
 392  * @return array Array version of input
 393  */
 394 function wfCgiToArray( $query ) {
 395         if ( isset( $query[0] ) && $query[0] == '?' ) {
 396                 $query = substr( $query, 1 );
 397         }
 398         $bits = explode( '&', $query );
 399         $ret = array();
 400         foreach ( $bits as $bit ) {
 401                 if ( $bit === '' ) {
 402                         continue;
 403                 }
 404                 if ( strpos( $bit, '=' ) === false ) {
 405                         // Pieces like &qwerty become 'qwerty' => '' (at least this is what php does)
 406                         $key = $bit;
 407                         $value = '';
 408                 } else {
 409                         list( $key, $value ) = explode( '=', $bit );
 410                 }
 411                 $key = urldecode( $key );
 412                 $value = urldecode( $value );
 413                 if ( strpos( $key, '[' ) !== false ) {
 414                         $keys = array_reverse( explode( '[', $key ) );
 415                         $key = array_pop( $keys );
 416                         $temp = $value;
 417                         foreach ( $keys as $k ) {
 418                                 $k = substr( $k, 0, -1 );
 419                                 $temp = array( $k => $temp );
 420                         }
 421                         if ( isset( $ret[$key] ) ) {
 422                                 $ret[$key] = array_merge( $ret[$key], $temp );
 423                         } else {
 424                                 $ret[$key] = $temp;
 425                         }
 426                 } else {
 427                         $ret[$key] = $value;
 428                 }
 429         }
 430         return $ret;
 431 }
 432
 433 /**
 434  * Append a query string to an existing URL, which may or may not already
 435  * have query string parameters already. If so, they will be combined.
 436  *
 437  * @param $url String
 438  * @param $query Mixed: string or associative array
 439  * @return string
 440  */
 441 function wfAppendQuery( $url, $query ) {
 442         if ( is_array( $query ) ) {
 443                 $query = wfArrayToCgi( $query );
 444         }
 445         if ( $query != '' ) {
 446                 if ( false === strpos( $url, '?' ) ) {
 447                         $url .= '?';
 448                 } else {
 449                         $url .= '&';
 450                 }
 451                 $url .= $query;
 452         }
 453         return $url;
 454 }
 455
 456 /**
 457  * Expand a potentially local URL to a fully-qualified URL.  Assumes $wgServer
 458  * is correct.
 459  *
 460  * The meaning of the PROTO_* constants is as follows:
 461  * PROTO_HTTP: Output a URL starting with http://
 462  * PROTO_HTTPS: Output a URL starting with https://
 463  * PROTO_RELATIVE: Output a URL starting with // (protocol-relative URL)
 464  * PROTO_CURRENT: Output a URL starting with either http:// or https:// , depending on which protocol was used for the current incoming request
 465  * PROTO_CANONICAL: For URLs without a domain, like /w/index.php , use $wgCanonicalServer. For protocol-relative URLs, use the protocol of $wgCanonicalServer
 466  * PROTO_INTERNAL: Like PROTO_CANONICAL, but uses $wgInternalServer instead of $wgCanonicalServer
 467  *
 468  * @todo this won't work with current-path-relative URLs
 469  * like "subdir/foo.html", etc.
 470  *
 471  * @param string $url either fully-qualified or a local path + query
 472  * @param $defaultProto Mixed: one of the PROTO_* constants. Determines the
 473  *                             protocol to use if $url or $wgServer is
 474  *                             protocol-relative
 475  * @return string Fully-qualified URL, current-path-relative URL or false if
 476  *                no valid URL can be constructed
 477  */
 478 function wfExpandUrl( $url, $defaultProto = PROTO_CURRENT ) {
 479         global $wgServer, $wgCanonicalServer, $wgInternalServer;
 480         $serverUrl = $wgServer;
 481         if ( $defaultProto === PROTO_CANONICAL ) {
 482                 $serverUrl = $wgCanonicalServer;
 483         }
 484         // Make $wgInternalServer fall back to $wgServer if not set
 485         if ( $defaultProto === PROTO_INTERNAL && $wgInternalServer !== false ) {
 486                 $serverUrl = $wgInternalServer;
 487         }
 488         if ( $defaultProto === PROTO_CURRENT ) {
 489                 $defaultProto = WebRequest::detectProtocol() . '://';
 490         }
 491
 492         // Analyze $serverUrl to obtain its protocol
 493         $bits = wfParseUrl( $serverUrl );
 494         $serverHasProto = $bits && $bits['scheme'] != '';
 495
 496         if ( $defaultProto === PROTO_CANONICAL || $defaultProto === PROTO_INTERNAL ) {
 497                 if ( $serverHasProto ) {
 498                         $defaultProto = $bits['scheme'] . '://';
 499                 } else {
 500                         // $wgCanonicalServer or $wgInternalServer doesn't have a protocol. This really isn't supposed to happen
 501                         // Fall back to HTTP in this ridiculous case
 502                         $defaultProto = PROTO_HTTP;
 503                 }
 504         }
 505
 506         $defaultProtoWithoutSlashes = substr( $defaultProto, 0, -2 );
 507
 508         if ( substr( $url, 0, 2 ) == '//' ) {
 509                 $url = $defaultProtoWithoutSlashes . $url;
 510         } elseif ( substr( $url, 0, 1 ) == '/' ) {
 511                 // If $serverUrl is protocol-relative, prepend $defaultProtoWithoutSlashes, otherwise leave it alone
 512                 $url = ( $serverHasProto ? '' : $defaultProtoWithoutSlashes ) . $serverUrl . $url;
 513         }
 514
 515         $bits = wfParseUrl( $url );
 516         if ( $bits && isset( $bits['path'] ) ) {
 517                 $bits['path'] = wfRemoveDotSegments( $bits['path'] );
 518                 return wfAssembleUrl( $bits );
 519         } elseif ( $bits ) {
 520                 # No path to expand
 521                 return $url;
 522         } elseif ( substr( $url, 0, 1 ) != '/' ) {
 523                 # URL is a relative path
 524                 return wfRemoveDotSegments( $url );
 525         }
 526
 527         # Expanded URL is not valid.
 528         return false;
 529 }
 530
 531 /**
 532  * This function will reassemble a URL parsed with wfParseURL.  This is useful
 533  * if you need to edit part of a URL and put it back together.
 534  *
 535  * This is the basic structure used (brackets contain keys for $urlParts):
 536  * [scheme][delimiter][user]:[pass]@[host]:[port][path]?[query]#[fragment]
 537  *
 538  * @todo Need to integrate this into wfExpandUrl (bug 32168)
 539  *
 540  * @since 1.19
 541  * @param array $urlParts URL parts, as output from wfParseUrl
 542  * @return string URL assembled from its component parts
 543  */
 544 function wfAssembleUrl( $urlParts ) {
 545         $result = '';
 546
 547         if ( isset( $urlParts['delimiter'] ) ) {
 548                 if ( isset( $urlParts['scheme'] ) ) {
 549                         $result .= $urlParts['scheme'];
 550                 }
 551
 552                 $result .= $urlParts['delimiter'];
 553         }
 554
 555         if ( isset( $urlParts['host'] ) ) {
 556                 if ( isset( $urlParts['user'] ) ) {
 557                         $result .= $urlParts['user'];
 558                         if ( isset( $urlParts['pass'] ) ) {
 559                                 $result .= ':' . $urlParts['pass'];
 560                         }
 561                         $result .= '@';
 562                 }
 563
 564                 $result .= $urlParts['host'];
 565
 566                 if ( isset( $urlParts['port'] ) ) {
 567                         $result .= ':' . $urlParts['port'];
 568                 }
 569         }
 570
 571         if ( isset( $urlParts['path'] ) ) {
 572                 $result .= $urlParts['path'];
 573         }
 574
 575         if ( isset( $urlParts['query'] ) ) {
 576                 $result .= '?' . $urlParts['query'];
 577         }
 578
 579         if ( isset( $urlParts['fragment'] ) ) {
 580                 $result .= '#' . $urlParts['fragment'];
 581         }
 582
 583         return $result;
 584 }
 585
 586 /**
 587  * Remove all dot-segments in the provided URL path.  For example,
 588  * '/a/./b/../c/' becomes '/a/c/'.  For details on the algorithm, please see
 589  * RFC3986 section 5.2.4.
 590  *
 591  * @todo Need to integrate this into wfExpandUrl (bug 32168)
 592  *
 593  * @param string $urlPath URL path, potentially containing dot-segments
 594  * @return string URL path with all dot-segments removed
 595  */
 596 function wfRemoveDotSegments( $urlPath ) {
 597         $output = '';
 598         $inputOffset = 0;
 599         $inputLength = strlen( $urlPath );
 600
 601         while ( $inputOffset < $inputLength ) {
 602                 $prefixLengthOne = substr( $urlPath, $inputOffset, 1 );
 603                 $prefixLengthTwo = substr( $urlPath, $inputOffset, 2 );
 604                 $prefixLengthThree = substr( $urlPath, $inputOffset, 3 );
 605                 $prefixLengthFour = substr( $urlPath, $inputOffset, 4 );
 606                 $trimOutput = false;
 607
 608                 if ( $prefixLengthTwo == './' ) {
 609                         # Step A, remove leading "./"
 610                         $inputOffset += 2;
 611                 } elseif ( $prefixLengthThree == '../' ) {
 612                         # Step A, remove leading "../"
 613                         $inputOffset += 3;
 614                 } elseif ( ( $prefixLengthTwo == '/.' ) && ( $inputOffset + 2 == $inputLength ) ) {
 615                         # Step B, replace leading "/.$" with "/"
 616                         $inputOffset += 1;
 617                         $urlPath[$inputOffset] = '/';
 618                 } elseif ( $prefixLengthThree == '/./' ) {
 619                         # Step B, replace leading "/./" with "/"
 620                         $inputOffset += 2;
 621                 } elseif ( $prefixLengthThree == '/..' && ( $inputOffset + 3 == $inputLength ) ) {
 622                         # Step C, replace leading "/..$" with "/" and
 623                         # remove last path component in output
 624                         $inputOffset += 2;
 625                         $urlPath[$inputOffset] = '/';
 626                         $trimOutput = true;
 627                 } elseif ( $prefixLengthFour == '/../' ) {
 628                         # Step C, replace leading "/../" with "/" and
 629                         # remove last path component in output
 630                         $inputOffset += 3;
 631                         $trimOutput = true;
 632                 } elseif ( ( $prefixLengthOne == '.' ) && ( $inputOffset + 1 == $inputLength ) ) {
 633                         # Step D, remove "^.$"
 634                         $inputOffset += 1;
 635                 } elseif ( ( $prefixLengthTwo == '..' ) && ( $inputOffset + 2 == $inputLength ) ) {
 636                         # Step D, remove "^..$"
 637                         $inputOffset += 2;
 638                 } else {
 639                         # Step E, move leading path segment to output
 640                         if ( $prefixLengthOne == '/' ) {
 641                                 $slashPos = strpos( $urlPath, '/', $inputOffset + 1 );
 642                         } else {
 643                                 $slashPos = strpos( $urlPath, '/', $inputOffset );
 644                         }
 645                         if ( $slashPos === false ) {
 646                                 $output .= substr( $urlPath, $inputOffset );
 647                                 $inputOffset = $inputLength;
 648                         } else {
 649                                 $output .= substr( $urlPath, $inputOffset, $slashPos - $inputOffset );
 650                                 $inputOffset += $slashPos - $inputOffset;
 651                         }
 652                 }
 653
 654                 if ( $trimOutput ) {
 655                         $slashPos = strrpos( $output, '/' );
 656                         if ( $slashPos === false ) {
 657                                 $output = '';
 658                         } else {
 659                                 $output = substr( $output, 0, $slashPos );
 660                         }
 661                 }
 662         }
 663
 664         return $output;
 665 }
 666
 667 /**
 668  * Returns a regular expression of url protocols
 669  *
 670  * @param bool $includeProtocolRelative If false, remove '//' from the returned protocol list.
 671  *        DO NOT USE this directly, use wfUrlProtocolsWithoutProtRel() instead
 672  * @return String
 673  */
 674 function wfUrlProtocols( $includeProtocolRelative = true ) {
 675         global $wgUrlProtocols;
 676
 677         // Cache return values separately based on $includeProtocolRelative
 678         static $withProtRel = null, $withoutProtRel = null;
 679         $cachedValue = $includeProtocolRelative ? $withProtRel : $withoutProtRel;
 680         if ( !is_null( $cachedValue ) ) {
 681                 return $cachedValue;
 682         }
 683
 684         // Support old-style $wgUrlProtocols strings, for backwards compatibility
 685         // with LocalSettings files from 1.5
 686         if ( is_array( $wgUrlProtocols ) ) {
 687                 $protocols = array();
 688                 foreach ( $wgUrlProtocols as $protocol ) {
 689                         // Filter out '//' if !$includeProtocolRelative
 690                         if ( $includeProtocolRelative || $protocol !== '//' ) {
 691                                 $protocols[] = preg_quote( $protocol, '/' );
 692                         }
 693                 }
 694
 695                 $retval = implode( '|', $protocols );
 696         } else {
 697                 // Ignore $includeProtocolRelative in this case
 698                 // This case exists for pre-1.6 compatibility, and we can safely assume
 699                 // that '//' won't appear in a pre-1.6 config because protocol-relative
 700                 // URLs weren't supported until 1.18
 701                 $retval = $wgUrlProtocols;
 702         }
 703
 704         // Cache return value
 705         if ( $includeProtocolRelative ) {
 706                 $withProtRel = $retval;
 707         } else {
 708                 $withoutProtRel = $retval;
 709         }
 710         return $retval;
 711 }
 712
 713 /**
 714  * Like wfUrlProtocols(), but excludes '//' from the protocol list. Use this if
 715  * you need a regex that matches all URL protocols but does not match protocol-
 716  * relative URLs
 717  * @return String
 718  */
 719 function wfUrlProtocolsWithoutProtRel() {
 720         return wfUrlProtocols( false );
 721 }
 722
 723 /**
 724  * parse_url() work-alike, but non-broken.  Differences:
 725  *
 726  * 1) Does not raise warnings on bad URLs (just returns false)
 727  * 2) Handles protocols that don't use :// (e.g., mailto: and news: , as well as protocol-relative URLs) correctly
 728  * 3) Adds a "delimiter" element to the array, either '://', ':' or '//' (see (2))
 729  *
 730  * @param string $url a URL to parse
 731  * @return Array: bits of the URL in an associative array, per PHP docs
 732  */
 733 function wfParseUrl( $url ) {
 734         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
 735
 736         // Protocol-relative URLs are handled really badly by parse_url(). It's so bad that the easiest
 737         // way to handle them is to just prepend 'http:' and strip the protocol out later
 738         $wasRelative = substr( $url, 0, 2 ) == '//';
 739         if ( $wasRelative ) {
 740                 $url = "http:$url";
 741         }
 742         wfSuppressWarnings();
 743         $bits = parse_url( $url );
 744         wfRestoreWarnings();
 745         // parse_url() returns an array without scheme for some invalid URLs, e.g.
 746         // parse_url("%0Ahttp://example.com") == array( 'host' => '%0Ahttp', 'path' => 'example.com' )
 747         if ( !$bits || !isset( $bits['scheme'] ) ) {
 748                 return false;
 749         }
 750
 751         // parse_url() incorrectly handles schemes case-sensitively. Convert it to lowercase.
 752         $bits['scheme'] = strtolower( $bits['scheme'] );
 753
 754         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
 755         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
 756                 $bits['delimiter'] = '://';
 757         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
 758                 $bits['delimiter'] = ':';
 759                 // parse_url detects for news: and mailto: the host part of an url as path
 760                 // We have to correct this wrong detection
 761                 if ( isset( $bits['path'] ) ) {
 762                         $bits['host'] = $bits['path'];
 763                         $bits['path'] = '';
 764                 }
 765         } else {
 766                 return false;
 767         }
 768
 769         /* Provide an empty host for eg. file:/// urls (see bug 28627) */
 770         if ( !isset( $bits['host'] ) ) {
 771                 $bits['host'] = '';
 772
 773                 // bug 45069
 774                 if ( isset( $bits['path'] ) ) {
 775                         /* parse_url loses the third / for file:///c:/ urls (but not on variants) */
 776                         if ( substr( $bits['path'], 0, 1 ) !== '/' ) {
 777                                 $bits['path'] = '/' . $bits['path'];
 778                         }
 779                 } else {
 780                         $bits['path'] = '';
 781                 }
 782         }
 783
 784         // If the URL was protocol-relative, fix scheme and delimiter
 785         if ( $wasRelative ) {
 786                 $bits['scheme'] = '';
 787                 $bits['delimiter'] = '//';
 788         }
 789         return $bits;
 790 }
 791
 792 /**
 793  * Take a URL, make sure it's expanded to fully qualified, and replace any
 794  * encoded non-ASCII Unicode characters with their UTF-8 original forms
 795  * for more compact display and legibility for local audiences.
 796  *
 797  * @todo handle punycode domains too
 798  *
 799  * @param $url string
 800  * @return string
 801  */
 802 function wfExpandIRI( $url ) {
 803         return preg_replace_callback( '/((?:%[89A-F][0-9A-F])+)/i', 'wfExpandIRI_callback', wfExpandUrl( $url ) );
 804 }
 805
 806 /**
 807  * Private callback for wfExpandIRI
 808  * @param array $matches
 809  * @return string
 810  */
 811 function wfExpandIRI_callback( $matches ) {
 812         return urldecode( $matches[1] );
 813 }
 814
 815 /**
 816  * Make URL indexes, appropriate for the el_index field of externallinks.
 817  *
 818  * @param $url String
 819  * @return array
 820  */
 821 function wfMakeUrlIndexes( $url ) {
 822         $bits = wfParseUrl( $url );
 823
 824         // Reverse the labels in the hostname, convert to lower case
 825         // For emails reverse domainpart only
 826         if ( $bits['scheme'] == 'mailto' ) {
 827                 $mailparts = explode( '@', $bits['host'], 2 );
 828                 if ( count( $mailparts ) === 2 ) {
 829                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
 830                 } else {
 831                         // No domain specified, don't mangle it
 832                         $domainpart = '';
 833                 }
 834                 $reversedHost = $domainpart . '@' . $mailparts[0];
 835         } else {
 836                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
 837         }
 838         // Add an extra dot to the end
 839         // Why? Is it in wrong place in mailto links?
 840         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
 841                 $reversedHost .= '.';
 842         }
 843         // Reconstruct the pseudo-URL
 844         $prot = $bits['scheme'];
 845         $index = $prot . $bits['delimiter'] . $reversedHost;
 846         // Leave out user and password. Add the port, path, query and fragment
 847         if ( isset( $bits['port'] ) ) {
 848                 $index .= ':' . $bits['port'];
 849         }
 850         if ( isset( $bits['path'] ) ) {
 851                 $index .= $bits['path'];
 852         } else {
 853                 $index .= '/';
 854         }
 855         if ( isset( $bits['query'] ) ) {
 856                 $index .= '?' . $bits['query'];
 857         }
 858         if ( isset( $bits['fragment'] ) ) {
 859                 $index .= '#' . $bits['fragment'];
 860         }
 861
 862         if ( $prot == '' ) {
 863                 return array( "http:$index", "https:$index" );
 864         } else {
 865                 return array( $index );
 866         }
 867 }
 868
 869 /**
 870  * Check whether a given URL has a domain that occurs in a given set of domains
 871  * @param string $url URL
 872  * @param array $domains Array of domains (strings)
 873  * @return bool True if the host part of $url ends in one of the strings in $domains
 874  */
 875 function wfMatchesDomainList( $url, $domains ) {
 876         $bits = wfParseUrl( $url );
 877         if ( is_array( $bits ) && isset( $bits['host'] ) ) {
 878                 foreach ( (array)$domains as $domain ) {
 879                         // FIXME: This gives false positives. http://nds-nl.wikipedia.org will match nl.wikipedia.org
 880                         // We should use something that interprets dots instead
 881                         if ( substr( $bits['host'], -strlen( $domain ) ) === $domain ) {
 882                                 return true;
 883                         }
 884                 }
 885         }
 886         return false;
 887 }
 888
 889 /**
 890  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
 891  * In normal operation this is a NOP.
 892  *
 893  * Controlling globals:
 894  * $wgDebugLogFile - points to the log file
 895  * $wgProfileOnly - if set, normal debug messages will not be recorded.
 896  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
 897  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
 898  *
 899  * @param $text String
 900  * @param bool $logonly set true to avoid appearing in HTML when $wgDebugComments is set
 901  */
 902 function wfDebug( $text, $logonly = false ) {
 903         global $wgDebugLogFile, $wgProfileOnly, $wgDebugRawPage, $wgDebugLogPrefix;
 904
 905         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
 906                 return;
 907         }
 908
 909         $timer = wfDebugTimer();
 910         if ( $timer !== '' ) {
 911                 $text = preg_replace( '/[^\n]/', $timer . '\0', $text, 1 );
 912         }
 913
 914         if ( !$logonly ) {
 915                 MWDebug::debugMsg( $text );
 916         }
 917
 918         if ( wfRunHooks( 'Debug', array( $text, null /* no log group */ ) ) ) {
 919                 if ( $wgDebugLogFile != '' && !$wgProfileOnly ) {
 920                         # Strip unprintables; they can switch terminal modes when binary data
 921                         # gets dumped, which is pretty annoying.
 922                         $text = preg_replace( '![\x00-\x08\x0b\x0c\x0e-\x1f]!', ' ', $text );
 923                         $text = $wgDebugLogPrefix . $text;
 924                         wfErrorLog( $text, $wgDebugLogFile );
 925                 }
 926         }
 927 }
 928
 929 /**
 930  * Returns true if debug logging should be suppressed if $wgDebugRawPage = false
 931  * @return bool
 932  */
 933 function wfIsDebugRawPage() {
 934         static $cache;
 935         if ( $cache !== null ) {
 936                 return $cache;
 937         }
 938         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
 939         if ( ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' )
 940                 || (
 941                         isset( $_SERVER['SCRIPT_NAME'] )
 942                         && substr( $_SERVER['SCRIPT_NAME'], -8 ) == 'load.php'
 943                 ) )
 944         {
 945                 $cache = true;
 946         } else {
 947                 $cache = false;
 948         }
 949         return $cache;
 950 }
 951
 952 /**
 953  * Get microsecond timestamps for debug logs
 954  *
 955  * @return string
 956  */
 957 function wfDebugTimer() {
 958         global $wgDebugTimestamps, $wgRequestTime;
 959
 960         if ( !$wgDebugTimestamps ) {
 961                 return '';
 962         }
 963
 964         $prefix = sprintf( "%6.4f", microtime( true ) - $wgRequestTime );
 965         $mem = sprintf( "%5.1fM", ( memory_get_usage( true ) / ( 1024 * 1024 ) ) );
 966         return "$prefix $mem  ";
 967 }
 968
 969 /**
 970  * Send a line giving PHP memory usage.
 971  *
 972  * @param bool $exact print exact values instead of kilobytes (default: false)
 973  */
 974 function wfDebugMem( $exact = false ) {
 975         $mem = memory_get_usage();
 976         if ( !$exact ) {
 977                 $mem = floor( $mem / 1024 ) . ' kilobytes';
 978         } else {
 979                 $mem .= ' bytes';
 980         }
 981         wfDebug( "Memory usage: $mem\n" );
 982 }
 983
 984 /**
 985  * Send a line to a supplementary debug log file, if configured, or main debug log if not.
 986  * $wgDebugLogGroups[$logGroup] should be set to a filename to send to a separate log.
 987  *
 988  * @param $logGroup String
 989  * @param $text String
 990  * @param bool $public whether to log the event in the public log if no private
 991  *                     log file is specified, (default true)
 992  */
 993 function wfDebugLog( $logGroup, $text, $public = true ) {
 994         global $wgDebugLogGroups;
 995         $text = trim( $text ) . "\n";
 996         if ( isset( $wgDebugLogGroups[$logGroup] ) ) {
 997                 $time = wfTimestamp( TS_DB );
 998                 $wiki = wfWikiID();
 999                 $host = wfHostname();
1000                 if ( wfRunHooks( 'Debug', array( $text, $logGroup ) ) ) {
1001                         wfErrorLog( "$time $host $wiki: $text", $wgDebugLogGroups[$logGroup] );
1002                 }
1003         } elseif ( $public === true ) {
1004                 wfDebug( "[$logGroup] $text", false );
1005         }
1006 }
1007
1008 /**
1009  * Log for database errors
1010  *
1011  * @param string $text database error message.
1012  */
1013 function wfLogDBError( $text ) {
1014         global $wgDBerrorLog, $wgDBerrorLogTZ;
1015         static $logDBErrorTimeZoneObject = null;
1016
1017         if ( $wgDBerrorLog ) {
1018                 $host = wfHostname();
1019                 $wiki = wfWikiID();
1020
1021                 if ( $wgDBerrorLogTZ && !$logDBErrorTimeZoneObject ) {
1022                         $logDBErrorTimeZoneObject = new DateTimeZone( $wgDBerrorLogTZ );
1023                 }
1024
1025                 // Workaround for https://bugs.php.net/bug.php?id=52063
1026                 // Can be removed when min PHP > 5.3.2
1027                 if ( $logDBErrorTimeZoneObject === null ) {
1028                         $d = date_create( "now" );
1029                 } else {
1030                         $d = date_create( "now", $logDBErrorTimeZoneObject );
1031                 }
1032
1033                 $date = $d->format( 'D M j G:i:s T Y' );
1034
1035                 $text = "$date\t$host\t$wiki\t$text";
1036                 wfErrorLog( $text, $wgDBerrorLog );
1037         }
1038 }
1039
1040 /**
1041  * Throws a warning that $function is deprecated
1042  *
1043  * @param $function String
1044  * @param string|bool $version Version of MediaWiki that the function was deprecated in (Added in 1.19).
1045  * @param string|bool $component Added in 1.19.
1046  * @param $callerOffset integer: How far up the call stack is the original
1047  *    caller. 2 = function that called the function that called
1048  *    wfDeprecated (Added in 1.20)
1049  *
1050  * @return null
1051  */
1052 function wfDeprecated( $function, $version = false, $component = false, $callerOffset = 2 ) {
1053         MWDebug::deprecated( $function, $version, $component, $callerOffset + 1 );
1054 }
1055
1056 /**
1057  * Send a warning either to the debug log or in a PHP error depending on
1058  * $wgDevelopmentWarnings. To log warnings in production, use wfLogWarning() instead.
1059  *
1060  * @param string $msg message to send
1061  * @param $callerOffset Integer: number of items to go back in the backtrace to
1062  *        find the correct caller (1 = function calling wfWarn, ...)
1063  * @param $level Integer: PHP error level; defaults to E_USER_NOTICE;
1064  *        only used when $wgDevelopmentWarnings is true
1065  */
1066 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
1067         MWDebug::warning( $msg, $callerOffset + 1, $level, 'auto' );
1068 }
1069
1070 /**
1071  * Send a warning as a PHP error and the debug log. This is intended for logging
1072  * warnings in production. For logging development warnings, use WfWarn instead.
1073  *
1074  * @param $msg String: message to send
1075  * @param $callerOffset Integer: number of items to go back in the backtrace to
1076  *        find the correct caller (1 = function calling wfLogWarning, ...)
1077  * @param $level Integer: PHP error level; defaults to E_USER_WARNING
1078  */
1079 function wfLogWarning( $msg, $callerOffset = 1, $level = E_USER_WARNING ) {
1080         MWDebug::warning( $msg, $callerOffset + 1, $level, 'production' );
1081 }
1082
1083 /**
1084  * Log to a file without getting "file size exceeded" signals.
1085  *
1086  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
1087  * send lines to the specified port, prefixed by the specified prefix and a space.
1088  *
1089  * @param $text String
1090  * @param string $file filename
1091  * @throws MWException
1092  */
1093 function wfErrorLog( $text, $file ) {
1094         if ( substr( $file, 0, 4 ) == 'udp:' ) {
1095                 # Needs the sockets extension
1096                 if ( preg_match( '!^(tcp|udp):(?://)?\[([0-9a-fA-F:]+)\]:(\d+)(?:/(.*))?$!', $file, $m ) ) {
1097                         // IPv6 bracketed host
1098                         $host = $m[2];
1099                         $port = intval( $m[3] );
1100                         $prefix = isset( $m[4] ) ? $m[4] : false;
1101                         $domain = AF_INET6;
1102                 } elseif ( preg_match( '!^(tcp|udp):(?://)?([a-zA-Z0-9.-]+):(\d+)(?:/(.*))?$!', $file, $m ) ) {
1103                         $host = $m[2];
1104                         if ( !IP::isIPv4( $host ) ) {
1105                                 $host = gethostbyname( $host );
1106                         }
1107                         $port = intval( $m[3] );
1108                         $prefix = isset( $m[4] ) ? $m[4] : false;
1109                         $domain = AF_INET;
1110                 } else {
1111                         throw new MWException( __METHOD__ . ': Invalid UDP specification' );
1112                 }
1113
1114                 // Clean it up for the multiplexer
1115                 if ( strval( $prefix ) !== '' ) {
1116                         $text = preg_replace( '/^/m', $prefix . ' ', $text );
1117
1118                         // Limit to 64KB
1119                         if ( strlen( $text ) > 65506 ) {
1120                                 $text = substr( $text, 0, 65506 );
1121                         }
1122
1123                         if ( substr( $text, -1 ) != "\n" ) {
1124                                 $text .= "\n";
1125                         }
1126                 } elseif ( strlen( $text ) > 65507 ) {
1127                         $text = substr( $text, 0, 65507 );
1128                 }
1129
1130                 $sock = socket_create( $domain, SOCK_DGRAM, SOL_UDP );
1131                 if ( !$sock ) {
1132                         return;
1133                 }
1134
1135                 socket_sendto( $sock, $text, strlen( $text ), 0, $host, $port );
1136                 socket_close( $sock );
1137         } else {
1138                 wfSuppressWarnings();
1139                 $exists = file_exists( $file );
1140                 $size = $exists ? filesize( $file ) : false;
1141                 if ( !$exists || ( $size !== false && $size + strlen( $text ) < 0x7fffffff ) ) {
1142                         file_put_contents( $file, $text, FILE_APPEND );
1143                 }
1144                 wfRestoreWarnings();
1145         }
1146 }
1147
1148 /**
1149  * @todo document
1150  */
1151 function wfLogProfilingData() {
1152         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
1153         global $wgProfileLimit, $wgUser;
1154
1155         StatCounter::singleton()->flush();
1156
1157         $profiler = Profiler::instance();
1158
1159         # Profiling must actually be enabled...
1160         if ( $profiler->isStub() ) {
1161                 return;
1162         }
1163
1164         // Get total page request time and only show pages that longer than
1165         // $wgProfileLimit time (default is 0)
1166         $elapsed = microtime( true ) - $wgRequestTime;
1167         if ( $elapsed <= $wgProfileLimit ) {
1168                 return;
1169         }
1170
1171         $profiler->logData();
1172
1173         // Check whether this should be logged in the debug file.
1174         if ( $wgDebugLogFile == '' || ( !$wgDebugRawPage && wfIsDebugRawPage() ) ) {
1175                 return;
1176         }
1177
1178         $forward = '';
1179         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
1180                 $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
1181         }
1182         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
1183                 $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
1184         }
1185         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
1186                 $forward .= ' from ' . $_SERVER['HTTP_FROM'];
1187         }
1188         if ( $forward ) {
1189                 $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
1190         }
1191         // Don't load $wgUser at this late stage just for statistics purposes
1192         // @todo FIXME: We can detect some anons even if it is not loaded. See User::getId()
1193         if ( $wgUser->isItemLoaded( 'id' ) && $wgUser->isAnon() ) {
1194                 $forward .= ' anon';
1195         }
1196
1197         // Command line script uses a FauxRequest object which does not have
1198         // any knowledge about an URL and throw an exception instead.
1199         try {
1200                 $requestUrl = $wgRequest->getRequestURL();
1201         } catch ( MWException $e ) {
1202                 $requestUrl = 'n/a';
1203         }
1204
1205         $log = sprintf( "%s\t%04.3f\t%s\n",
1206                 gmdate( 'YmdHis' ), $elapsed,
1207                 urldecode( $requestUrl . $forward ) );
1208
1209         wfErrorLog( $log . $profiler->getOutput(), $wgDebugLogFile );
1210 }
1211
1212 /**
1213  * Increment a statistics counter
1214  *
1215  * @param $key String
1216  * @param $count Int
1217  * @return void
1218  */
1219 function wfIncrStats( $key, $count = 1 ) {
1220         StatCounter::singleton()->incr( $key, $count );
1221 }
1222
1223 /**
1224  * Check if the wiki read-only lock file is present. This can be used to lock
1225  * off editing functions, but doesn't guarantee that the database will not be
1226  * modified.
1227  *
1228  * @return bool
1229  */
1230 function wfReadOnly() {
1231         global $wgReadOnlyFile, $wgReadOnly;
1232
1233         if ( !is_null( $wgReadOnly ) ) {
1234                 return (bool)$wgReadOnly;
1235         }
1236         if ( $wgReadOnlyFile == '' ) {
1237                 return false;
1238         }
1239         // Set $wgReadOnly for faster access next time
1240         if ( is_file( $wgReadOnlyFile ) ) {
1241                 $wgReadOnly = file_get_contents( $wgReadOnlyFile );
1242         } else {
1243                 $wgReadOnly = false;
1244         }
1245         return (bool)$wgReadOnly;
1246 }
1247
1248 /**
1249  * @return bool
1250  */
1251 function wfReadOnlyReason() {
1252         global $wgReadOnly;
1253         wfReadOnly();
1254         return $wgReadOnly;
1255 }
1256
1257 /**
1258  * Return a Language object from $langcode
1259  *
1260  * @param $langcode Mixed: either:
1261  *                  - a Language object
1262  *                  - code of the language to get the message for, if it is
1263  *                    a valid code create a language for that language, if
1264  *                    it is a string but not a valid code then make a basic
1265  *                    language object
1266  *                  - a boolean: if it's false then use the global object for
1267  *                    the current user's language (as a fallback for the old parameter
1268  *                    functionality), or if it is true then use global object
1269  *                    for the wiki's content language.
1270  * @return Language object
1271  */
1272 function wfGetLangObj( $langcode = false ) {
1273         # Identify which language to get or create a language object for.
1274         # Using is_object here due to Stub objects.
1275         if ( is_object( $langcode ) ) {
1276                 # Great, we already have the object (hopefully)!
1277                 return $langcode;
1278         }
1279
1280         global $wgContLang, $wgLanguageCode;
1281         if ( $langcode === true || $langcode === $wgLanguageCode ) {
1282                 # $langcode is the language code of the wikis content language object.
1283                 # or it is a boolean and value is true
1284                 return $wgContLang;
1285         }
1286
1287         global $wgLang;
1288         if ( $langcode === false || $langcode === $wgLang->getCode() ) {
1289                 # $langcode is the language code of user language object.
1290                 # or it was a boolean and value is false
1291                 return $wgLang;
1292         }
1293
1294         $validCodes = array_keys( Language::fetchLanguageNames() );
1295         if ( in_array( $langcode, $validCodes ) ) {
1296                 # $langcode corresponds to a valid language.
1297                 return Language::factory( $langcode );
1298         }
1299
1300         # $langcode is a string, but not a valid language code; use content language.
1301         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
1302         return $wgContLang;
1303 }
1304
1305 /**
1306  * Old function when $wgBetterDirectionality existed
1307  * All usage removed, wfUILang can be removed in near future
1308  *
1309  * @deprecated since 1.18
1310  * @return Language
1311  */
1312 function wfUILang() {
1313         wfDeprecated( __METHOD__, '1.18' );
1314         global $wgLang;
1315         return $wgLang;
1316 }
1317
1318 /**
1319  * This is the function for getting translated interface messages.
1320  *
1321  * @see Message class for documentation how to use them.
1322  * @see https://www.mediawiki.org/wiki/Manual:Messages_API
1323  *
1324  * This function replaces all old wfMsg* functions.
1325  *
1326  * @param $key \string Message key.
1327  * Varargs: normal message parameters.
1328  * @return Message
1329  * @since 1.17
1330  */
1331 function wfMessage( $key /*...*/) {
1332         $params = func_get_args();
1333         array_shift( $params );
1334         if ( isset( $params[0] ) && is_array( $params[0] ) ) {
1335                 $params = $params[0];
1336         }
1337         return new Message( $key, $params );
1338 }
1339
1340 /**
1341  * This function accepts multiple message keys and returns a message instance
1342  * for the first message which is non-empty. If all messages are empty then an
1343  * instance of the first message key is returned.
1344  * @param varargs: message keys
1345  * @return Message
1346  * @since 1.18
1347  */
1348 function wfMessageFallback( /*...*/ ) {
1349         $args = func_get_args();
1350         return MWFunction::callArray( 'Message::newFallbackSequence', $args );
1351 }
1352
1353 /**
1354  * Get a message from anywhere, for the current user language.
1355  *
1356  * Use wfMsgForContent() instead if the message should NOT
1357  * change depending on the user preferences.
1358  *
1359  * @deprecated since 1.18
1360  *
1361  * @param string $key lookup key for the message, usually
1362  *    defined in languages/Language.php
1363  *
1364  * Parameters to the message, which can be used to insert variable text into
1365  * it, can be passed to this function in the following formats:
1366  * - One per argument, starting at the second parameter
1367  * - As an array in the second parameter
1368  * These are not shown in the function definition.
1369  *
1370  * @return String
1371  */
1372 function wfMsg( $key ) {
1373         wfDeprecated( __METHOD__, '1.21' );
1374
1375         $args = func_get_args();
1376         array_shift( $args );
1377         return wfMsgReal( $key, $args );
1378 }
1379
1380 /**
1381  * Same as above except doesn't transform the message
1382  *
1383  * @deprecated since 1.18
1384  *
1385  * @param $key String
1386  * @return String
1387  */
1388 function wfMsgNoTrans( $key ) {
1389         wfDeprecated( __METHOD__, '1.21' );
1390
1391         $args = func_get_args();
1392         array_shift( $args );
1393         return wfMsgReal( $key, $args, true, false, false );
1394 }
1395
1396 /**
1397  * Get a message from anywhere, for the current global language
1398  * set with $wgLanguageCode.
1399  *
1400  * Use this if the message should NOT change dependent on the
1401  * language set in the user's preferences. This is the case for
1402  * most text written into logs, as well as link targets (such as
1403  * the name of the copyright policy page). Link titles, on the
1404  * other hand, should be shown in the UI language.
1405  *
1406  * Note that MediaWiki allows users to change the user interface
1407  * language in their preferences, but a single installation
1408  * typically only contains content in one language.
1409  *
1410  * Be wary of this distinction: If you use wfMsg() where you should
1411  * use wfMsgForContent(), a user of the software may have to
1412  * customize potentially hundreds of messages in
1413  * order to, e.g., fix a link in every possible language.
1414  *
1415  * @deprecated since 1.18
1416  *
1417  * @param string $key lookup key for the message, usually
1418  *     defined in languages/Language.php
1419  * @return String
1420  */
1421 function wfMsgForContent( $key ) {
1422         wfDeprecated( __METHOD__, '1.21' );
1423
1424         global $wgForceUIMsgAsContentMsg;
1425         $args = func_get_args();
1426         array_shift( $args );
1427         $forcontent = true;
1428         if ( is_array( $wgForceUIMsgAsContentMsg ) &&
1429                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
1430         {
1431                 $forcontent = false;
1432         }
1433         return wfMsgReal( $key, $args, true, $forcontent );
1434 }
1435
1436 /**
1437  * Same as above except doesn't transform the message
1438  *
1439  * @deprecated since 1.18
1440  *
1441  * @param $key String
1442  * @return String
1443  */
1444 function wfMsgForContentNoTrans( $key ) {
1445         wfDeprecated( __METHOD__, '1.21' );
1446
1447         global $wgForceUIMsgAsContentMsg;
1448         $args = func_get_args();
1449         array_shift( $args );
1450         $forcontent = true;
1451         if ( is_array( $wgForceUIMsgAsContentMsg ) &&
1452                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
1453         {
1454                 $forcontent = false;
1455         }
1456         return wfMsgReal( $key, $args, true, $forcontent, false );
1457 }
1458
1459 /**
1460  * Really get a message
1461  *
1462  * @deprecated since 1.18
1463  *
1464  * @param string $key key to get.
1465  * @param $args
1466  * @param $useDB Boolean
1467  * @param $forContent Mixed: Language code, or false for user lang, true for content lang.
1468  * @param $transform Boolean: Whether or not to transform the message.
1469  * @return String: the requested message.
1470  */
1471 function wfMsgReal( $key, $args, $useDB = true, $forContent = false, $transform = true ) {
1472         wfDeprecated( __METHOD__, '1.21' );
1473
1474         wfProfileIn( __METHOD__ );
1475         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
1476         $message = wfMsgReplaceArgs( $message, $args );
1477         wfProfileOut( __METHOD__ );
1478         return $message;
1479 }
1480
1481 /**
1482  * Fetch a message string value, but don't replace any keys yet.
1483  *
1484  * @deprecated since 1.18
1485  *
1486  * @param $key String
1487  * @param $useDB Bool
1488  * @param string $langCode Code of the language to get the message for, or
1489  *                  behaves as a content language switch if it is a boolean.
1490  * @param $transform Boolean: whether to parse magic words, etc.
1491  * @return string
1492  */
1493 function wfMsgGetKey( $key, $useDB = true, $langCode = false, $transform = true ) {
1494         wfDeprecated( __METHOD__, '1.21' );
1495
1496         wfRunHooks( 'NormalizeMessageKey', array( &$key, &$useDB, &$langCode, &$transform ) );
1497
1498         $cache = MessageCache::singleton();
1499         $message = $cache->get( $key, $useDB, $langCode );
1500         if ( $message === false ) {
1501                 $message = '&lt;' . htmlspecialchars( $key ) . '&gt;';
1502         } elseif ( $transform ) {
1503                 $message = $cache->transform( $message );
1504         }
1505         return $message;
1506 }
1507
1508 /**
1509  * Replace message parameter keys on the given formatted output.
1510  *
1511  * @param $message String
1512  * @param $args Array
1513  * @return string
1514  * @private
1515  */
1516 function wfMsgReplaceArgs( $message, $args ) {
1517         # Fix windows line-endings
1518         # Some messages are split with explode("\n", $msg)
1519         $message = str_replace( "\r", '', $message );
1520
1521         // Replace arguments
1522         if ( count( $args ) ) {
1523                 if ( is_array( $args[0] ) ) {
1524                         $args = array_values( $args[0] );
1525                 }
1526                 $replacementKeys = array();
1527                 foreach ( $args as $n => $param ) {
1528                         $replacementKeys['$' . ( $n + 1 )] = $param;
1529                 }
1530                 $message = strtr( $message, $replacementKeys );
1531         }
1532
1533         return $message;
1534 }
1535
1536 /**
1537  * Return an HTML-escaped version of a message.
1538  * Parameter replacements, if any, are done *after* the HTML-escaping,
1539  * so parameters may contain HTML (eg links or form controls). Be sure
1540  * to pre-escape them if you really do want plaintext, or just wrap
1541  * the whole thing in htmlspecialchars().
1542  *
1543  * @deprecated since 1.18
1544  *
1545  * @param $key String
1546  * @param string ... parameters
1547  * @return string
1548  */
1549 function wfMsgHtml( $key ) {
1550         wfDeprecated( __METHOD__, '1.21' );
1551
1552         $args = func_get_args();
1553         array_shift( $args );
1554         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key ) ), $args );
1555 }
1556
1557 /**
1558  * Return an HTML version of message
1559  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
1560  * so parameters may contain HTML (eg links or form controls). Be sure
1561  * to pre-escape them if you really do want plaintext, or just wrap
1562  * the whole thing in htmlspecialchars().
1563  *
1564  * @deprecated since 1.18
1565  *
1566  * @param $key String
1567  * @param string ... parameters
1568  * @return string
1569  */
1570 function wfMsgWikiHtml( $key ) {
1571         wfDeprecated( __METHOD__, '1.21' );
1572
1573         $args = func_get_args();
1574         array_shift( $args );
1575         return wfMsgReplaceArgs(
1576                 MessageCache::singleton()->parse( wfMsgGetKey( $key ), null,
1577                 /* can't be set to false */ true, /* interface */ true )->getText(),
1578                 $args );
1579 }
1580
1581 /**
1582  * Returns message in the requested format
1583  *
1584  * @deprecated since 1.18
1585  *
1586  * @param string $key key of the message
1587  * @param array $options processing rules. Can take the following options:
1588  *   <i>parse</i>: parses wikitext to HTML
1589  *   <i>parseinline</i>: parses wikitext to HTML and removes the surrounding
1590  *       p's added by parser or tidy
1591  *   <i>escape</i>: filters message through htmlspecialchars
1592  *   <i>escapenoentities</i>: same, but allows entity references like &#160; through
1593  *   <i>replaceafter</i>: parameters are substituted after parsing or escaping
1594  *   <i>parsemag</i>: transform the message using magic phrases
1595  *   <i>content</i>: fetch message for content language instead of interface
1596  * Also can accept a single associative argument, of the form 'language' => 'xx':
1597  *   <i>language</i>: Language object or language code to fetch message for
1598  *       (overridden by <i>content</i>).
1599  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
1600  *
1601  * @return String
1602  */
1603 function wfMsgExt( $key, $options ) {
1604         wfDeprecated( __METHOD__, '1.21' );
1605
1606         $args = func_get_args();
1607         array_shift( $args );
1608         array_shift( $args );
1609         $options = (array)$options;
1610
1611         foreach ( $options as $arrayKey => $option ) {
1612                 if ( !preg_match( '/^[0-9]+|language$/', $arrayKey ) ) {
1613                         # An unknown index, neither numeric nor "language"
1614                         wfWarn( "wfMsgExt called with incorrect parameter key $arrayKey", 1, E_USER_WARNING );
1615                 } elseif ( preg_match( '/^[0-9]+$/', $arrayKey ) && !in_array( $option,
1616                 array( 'parse', 'parseinline', 'escape', 'escapenoentities',
1617                 'replaceafter', 'parsemag', 'content' ) ) ) {
1618                         # A numeric index with unknown value
1619                         wfWarn( "wfMsgExt called with incorrect parameter $option", 1, E_USER_WARNING );
1620                 }
1621         }
1622
1623         if ( in_array( 'content', $options, true ) ) {
1624                 $forContent = true;
1625                 $langCode = true;
1626                 $langCodeObj = null;
1627         } elseif ( array_key_exists( 'language', $options ) ) {
1628                 $forContent = false;
1629                 $langCode = wfGetLangObj( $options['language'] );
1630                 $langCodeObj = $langCode;
1631         } else {
1632                 $forContent = false;
1633                 $langCode = false;
1634                 $langCodeObj = null;
1635         }
1636
1637         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
1638
1639         if ( !in_array( 'replaceafter', $options, true ) ) {
1640                 $string = wfMsgReplaceArgs( $string, $args );
1641         }
1642
1643         $messageCache = MessageCache::singleton();
1644         $parseInline = in_array( 'parseinline', $options, true );
1645         if ( in_array( 'parse', $options, true ) || $parseInline ) {
1646                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj );
1647                 if ( $string instanceof ParserOutput ) {
1648                         $string = $string->getText();
1649                 }
1650
1651                 if ( $parseInline ) {
1652                         $m = array();
1653                         if ( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
1654                                 $string = $m[1];
1655                         }
1656                 }
1657         } elseif ( in_array( 'parsemag', $options, true ) ) {
1658                 $string = $messageCache->transform( $string,
1659                                 !$forContent, $langCodeObj );
1660         }
1661
1662         if ( in_array( 'escape', $options, true ) ) {
1663                 $string = htmlspecialchars ( $string );
1664         } elseif ( in_array( 'escapenoentities', $options, true ) ) {
1665                 $string = Sanitizer::escapeHtmlAllowEntities( $string );
1666         }
1667
1668         if ( in_array( 'replaceafter', $options, true ) ) {
1669                 $string = wfMsgReplaceArgs( $string, $args );
1670         }
1671
1672         return $string;
1673 }
1674
1675 /**
1676  * Since wfMsg() and co suck, they don't return false if the message key they
1677  * looked up didn't exist but instead the key wrapped in <>'s, this function checks for the
1678  * nonexistence of messages by checking the MessageCache::get() result directly.
1679  *
1680  * @deprecated since 1.18. Use Message::isDisabled().
1681  *
1682  * @param $key      String: the message key looked up
1683  * @return Boolean True if the message *doesn't* exist.
1684  */
1685 function wfEmptyMsg( $key ) {
1686         wfDeprecated( __METHOD__, '1.21' );
1687
1688         return MessageCache::singleton()->get( $key, /*useDB*/true, /*content*/false ) === false;
1689 }
1690
1691 /**
1692  * Throw a debugging exception. This function previously once exited the process,
1693  * but now throws an exception instead, with similar results.
1694  *
1695  * @param string $msg message shown when dying.
1696  * @throws MWException
1697  */
1698 function wfDebugDieBacktrace( $msg = '' ) {
1699         throw new MWException( $msg );
1700 }
1701
1702 /**
1703  * Fetch server name for use in error reporting etc.
1704  * Use real server name if available, so we know which machine
1705  * in a server farm generated the current page.
1706  *
1707  * @return string
1708  */
1709 function wfHostname() {
1710         static $host;
1711         if ( is_null( $host ) ) {
1712
1713                 # Hostname overriding
1714                 global $wgOverrideHostname;
1715                 if ( $wgOverrideHostname !== false ) {
1716                         # Set static and skip any detection
1717                         $host = $wgOverrideHostname;
1718                         return $host;
1719                 }
1720
1721                 if ( function_exists( 'posix_uname' ) ) {
1722                         // This function not present on Windows
1723                         $uname = posix_uname();
1724                 } else {
1725                         $uname = false;
1726                 }
1727                 if ( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1728                         $host = $uname['nodename'];
1729                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1730                         # Windows computer name
1731                         $host = getenv( 'COMPUTERNAME' );
1732                 } else {
1733                         # This may be a virtual server.
1734                         $host = $_SERVER['SERVER_NAME'];
1735                 }
1736         }
1737         return $host;
1738 }
1739
1740 /**
1741  * Returns a HTML comment with the elapsed time since request.
1742  * This method has no side effects.
1743  *
1744  * @return string
1745  */
1746 function wfReportTime() {
1747         global $wgRequestTime, $wgShowHostnames;
1748
1749         $elapsed = microtime( true ) - $wgRequestTime;
1750
1751         return $wgShowHostnames
1752                 ? sprintf( '<!-- Served by %s in %01.3f secs. -->', wfHostname(), $elapsed )
1753                 : sprintf( '<!-- Served in %01.3f secs. -->', $elapsed );
1754 }
1755
1756 /**
1757  * Safety wrapper for debug_backtrace().
1758  *
1759  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
1760  * murky circumstances, which may be triggered in part by stub objects
1761  * or other fancy talking'.
1762  *
1763  * Will return an empty array if Zend Optimizer is detected or if
1764  * debug_backtrace is disabled, otherwise the output from
1765  * debug_backtrace() (trimmed).
1766  *
1767  * @param int $limit This parameter can be used to limit the number of stack frames returned
1768  *
1769  * @return array of backtrace information
1770  */
1771 function wfDebugBacktrace( $limit = 0 ) {
1772         static $disabled = null;
1773
1774         if ( extension_loaded( 'Zend Optimizer' ) ) {
1775                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
1776                 return array();
1777         }
1778
1779         if ( is_null( $disabled ) ) {
1780                 $disabled = false;
1781                 $functions = explode( ',', ini_get( 'disable_functions' ) );
1782                 $functions = array_map( 'trim', $functions );
1783                 $functions = array_map( 'strtolower', $functions );
1784                 if ( in_array( 'debug_backtrace', $functions ) ) {
1785                         wfDebug( "debug_backtrace is in disabled_functions\n" );
1786                         $disabled = true;
1787                 }
1788         }
1789         if ( $disabled ) {
1790                 return array();
1791         }
1792
1793         if ( $limit && version_compare( PHP_VERSION, '5.4.0', '>=' ) ) {
1794                 return array_slice( debug_backtrace( DEBUG_BACKTRACE_PROVIDE_OBJECT, $limit + 1 ), 1 );
1795         } else {
1796                 return array_slice( debug_backtrace(), 1 );
1797         }
1798 }
1799
1800 /**
1801  * Get a debug backtrace as a string
1802  *
1803  * @return string
1804  */
1805 function wfBacktrace() {
1806         global $wgCommandLineMode;
1807
1808         if ( $wgCommandLineMode ) {
1809                 $msg = '';
1810         } else {
1811                 $msg = "<ul>\n";
1812         }
1813         $backtrace = wfDebugBacktrace();
1814         foreach ( $backtrace as $call ) {
1815                 if ( isset( $call['file'] ) ) {
1816                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
1817                         $file = $f[count( $f ) - 1];
1818                 } else {
1819                         $file = '-';
1820                 }
1821                 if ( isset( $call['line'] ) ) {
1822                         $line = $call['line'];
1823                 } else {
1824                         $line = '-';
1825                 }
1826                 if ( $wgCommandLineMode ) {
1827                         $msg .= "$file line $line calls ";
1828                 } else {
1829                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
1830                 }
1831                 if ( !empty( $call['class'] ) ) {
1832                         $msg .= $call['class'] . $call['type'];
1833                 }
1834                 $msg .= $call['function'] . '()';
1835
1836                 if ( $wgCommandLineMode ) {
1837                         $msg .= "\n";
1838                 } else {
1839                         $msg .= "</li>\n";
1840                 }
1841         }
1842         if ( $wgCommandLineMode ) {
1843                 $msg .= "\n";
1844         } else {
1845                 $msg .= "</ul>\n";
1846         }
1847
1848         return $msg;
1849 }
1850
1851 /**
1852  * Get the name of the function which called this function
1853  * wfGetCaller( 1 ) is the function with the wfGetCaller() call (ie. __FUNCTION__)
1854  * wfGetCaller( 2 ) [default] is the caller of the function running wfGetCaller()
1855  * wfGetCaller( 3 ) is the parent of that.
1856  *
1857  * @param $level Int
1858  * @return string
1859  */
1860 function wfGetCaller( $level = 2 ) {
1861         $backtrace = wfDebugBacktrace( $level + 1 );
1862         if ( isset( $backtrace[$level] ) ) {
1863                 return wfFormatStackFrame( $backtrace[$level] );
1864         } else {
1865                 return 'unknown';
1866         }
1867 }
1868
1869 /**
1870  * Return a string consisting of callers in the stack. Useful sometimes
1871  * for profiling specific points.
1872  *
1873  * @param int $limit The maximum depth of the stack frame to return, or false for
1874  *               the entire stack.
1875  * @return String
1876  */
1877 function wfGetAllCallers( $limit = 3 ) {
1878         $trace = array_reverse( wfDebugBacktrace() );
1879         if ( !$limit || $limit > count( $trace ) - 1 ) {
1880                 $limit = count( $trace ) - 1;
1881         }
1882         $trace = array_slice( $trace, -$limit - 1, $limit );
1883         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1884 }
1885
1886 /**
1887  * Return a string representation of frame
1888  *
1889  * @param $frame Array
1890  * @return string
1891  */
1892 function wfFormatStackFrame( $frame ) {
1893         return isset( $frame['class'] ) ?
1894                 $frame['class'] . '::' . $frame['function'] :
1895                 $frame['function'];
1896 }
1897
1898 /* Some generic result counters, pulled out of SearchEngine */
1899
1900 /**
1901  * @todo document
1902  *
1903  * @param $offset Int
1904  * @param $limit Int
1905  * @return String
1906  */
1907 function wfShowingResults( $offset, $limit ) {
1908         return wfMessage( 'showingresults' )->numParams( $limit, $offset + 1 )->parse();
1909 }
1910
1911 /**
1912  * Generate (prev x| next x) (20|50|100...) type links for paging
1913  *
1914  * @param $offset String
1915  * @param $limit Integer
1916  * @param $link String
1917  * @param string $query optional URL query parameter string
1918  * @param bool $atend optional param for specified if this is the last page
1919  * @return String
1920  * @deprecated in 1.19; use Language::viewPrevNext() instead
1921  */
1922 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
1923         wfDeprecated( __METHOD__, '1.19' );
1924
1925         global $wgLang;
1926
1927         $query = wfCgiToArray( $query );
1928
1929         if ( is_object( $link ) ) {
1930                 $title = $link;
1931         } else {
1932                 $title = Title::newFromText( $link );
1933                 if ( is_null( $title ) ) {
1934                         return false;
1935                 }
1936         }
1937
1938         return $wgLang->viewPrevNext( $title, $offset, $limit, $query, $atend );
1939 }
1940
1941 /**
1942  * Make a list item, used by various special pages
1943  *
1944  * @param string $page Page link
1945  * @param string $details Text between brackets
1946  * @param $oppositedm Boolean   Add the direction mark opposite to your
1947  *                                                              language, to display text properly
1948  * @return String
1949  * @deprecated since 1.19; use Language::specialList() instead
1950  */
1951 function wfSpecialList( $page, $details, $oppositedm = true ) {
1952         wfDeprecated( __METHOD__, '1.19' );
1953
1954         global $wgLang;
1955         return $wgLang->specialList( $page, $details, $oppositedm );
1956 }
1957
1958 /**
1959  * @todo document
1960  * @todo FIXME: We may want to blacklist some broken browsers
1961  *
1962  * @param $force Bool
1963  * @return bool Whereas client accept gzip compression
1964  */
1965 function wfClientAcceptsGzip( $force = false ) {
1966         static $result = null;
1967         if ( $result === null || $force ) {
1968                 $result = false;
1969                 if ( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1970                         # @todo FIXME: We may want to blacklist some broken browsers
1971                         $m = array();
1972                         if ( preg_match(
1973                                 '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1974                                 $_SERVER['HTTP_ACCEPT_ENCODING'],
1975                                 $m )
1976                         )
1977                         {
1978                                 if ( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1979                                         $result = false;
1980                                         return $result;
1981                                 }
1982                                 wfDebug( "wfClientAcceptsGzip: client accepts gzip.\n" );
1983                                 $result = true;
1984                         }
1985                 }
1986         }
1987         return $result;
1988 }
1989
1990 /**
1991  * Obtain the offset and limit values from the request string;
1992  * used in special pages
1993  *
1994  * @param int $deflimit default limit if none supplied
1995  * @param string $optionname Name of a user preference to check against
1996  * @return array
1997  *
1998  */
1999 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
2000         global $wgRequest;
2001         return $wgRequest->getLimitOffset( $deflimit, $optionname );
2002 }
2003
2004 /**
2005  * Escapes the given text so that it may be output using addWikiText()
2006  * without any linking, formatting, etc. making its way through. This
2007  * is achieved by substituting certain characters with HTML entities.
2008  * As required by the callers, "<nowiki>" is not used.
2009  *
2010  * @param string $text text to be escaped
2011  * @return String
2012  */
2013 function wfEscapeWikiText( $text ) {
2014         $text = strtr( "\n$text", array(
2015                 '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
2016                 '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
2017                 '{' => '&#123;', '|' => '&#124;', '}' => '&#125;',
2018                 "\n#" => "\n&#35;", "\n*" => "\n&#42;",
2019                 "\n:" => "\n&#58;", "\n;" => "\n&#59;",
2020                 '://' => '&#58;//', 'ISBN ' => 'ISBN&#32;', 'RFC ' => 'RFC&#32;',
2021         ) );
2022         return substr( $text, 1 );
2023 }
2024
2025 /**
2026  * Get the current unix timestamp with microseconds.  Useful for profiling
2027  * @return Float
2028  */
2029 function wfTime() {
2030         return microtime( true );
2031 }
2032
2033 /**
2034  * Sets dest to source and returns the original value of dest
2035  * If source is NULL, it just returns the value, it doesn't set the variable
2036  * If force is true, it will set the value even if source is NULL
2037  *
2038  * @param $dest Mixed
2039  * @param $source Mixed
2040  * @param $force Bool
2041  * @return Mixed
2042  */
2043 function wfSetVar( &$dest, $source, $force = false ) {
2044         $temp = $dest;
2045         if ( !is_null( $source ) || $force ) {
2046                 $dest = $source;
2047         }
2048         return $temp;
2049 }
2050
2051 /**
2052  * As for wfSetVar except setting a bit
2053  *
2054  * @param $dest Int
2055  * @param $bit Int
2056  * @param $state Bool
2057  *
2058  * @return bool
2059  */
2060 function wfSetBit( &$dest, $bit, $state = true ) {
2061         $temp = (bool)( $dest & $bit );
2062         if ( !is_null( $state ) ) {
2063                 if ( $state ) {
2064                         $dest |= $bit;
2065                 } else {
2066                         $dest &= ~$bit;
2067                 }
2068         }
2069         return $temp;
2070 }
2071
2072 /**
2073  * A wrapper around the PHP function var_export().
2074  * Either print it or add it to the regular output ($wgOut).
2075  *
2076  * @param $var mixed A PHP variable to dump.
2077  */
2078 function wfVarDump( $var ) {
2079         global $wgOut;
2080         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
2081         if ( headers_sent() || !isset( $wgOut ) || !is_object( $wgOut ) ) {
2082                 print $s;
2083         } else {
2084                 $wgOut->addHTML( $s );
2085         }
2086 }
2087
2088 /**
2089  * Provide a simple HTTP error.
2090  *
2091  * @param $code Int|String
2092  * @param $label String
2093  * @param $desc String
2094  */
2095 function wfHttpError( $code, $label, $desc ) {
2096         global $wgOut;
2097         $wgOut->disable();
2098         header( "HTTP/1.0 $code $label" );
2099         header( "Status: $code $label" );
2100         $wgOut->sendCacheControl();
2101
2102         header( 'Content-type: text/html; charset=utf-8' );
2103         print "<!doctype html>" .
2104                 '<html><head><title>' .
2105                 htmlspecialchars( $label ) .
2106                 '</title></head><body><h1>' .
2107                 htmlspecialchars( $label ) .
2108                 '</h1><p>' .
2109                 nl2br( htmlspecialchars( $desc ) ) .
2110                 "</p></body></html>\n";
2111 }
2112
2113 /**
2114  * Clear away any user-level output buffers, discarding contents.
2115  *
2116  * Suitable for 'starting afresh', for instance when streaming
2117  * relatively large amounts of data without buffering, or wanting to
2118  * output image files without ob_gzhandler's compression.
2119  *
2120  * The optional $resetGzipEncoding parameter controls suppression of
2121  * the Content-Encoding header sent by ob_gzhandler; by default it
2122  * is left. See comments for wfClearOutputBuffers() for why it would
2123  * be used.
2124  *
2125  * Note that some PHP configuration options may add output buffer
2126  * layers which cannot be removed; these are left in place.
2127  *
2128  * @param $resetGzipEncoding Bool
2129  */
2130 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
2131         if ( $resetGzipEncoding ) {
2132                 // Suppress Content-Encoding and Content-Length
2133                 // headers from 1.10+s wfOutputHandler
2134                 global $wgDisableOutputCompression;
2135                 $wgDisableOutputCompression = true;
2136         }
2137         while ( $status = ob_get_status() ) {
2138                 if ( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
2139                         // Probably from zlib.output_compression or other
2140                         // PHP-internal setting which can't be removed.
2141                         //
2142                         // Give up, and hope the result doesn't break
2143                         // output behavior.
2144                         break;
2145                 }
2146                 if ( !ob_end_clean() ) {
2147                         // Could not remove output buffer handler; abort now
2148                         // to avoid getting in some kind of infinite loop.
2149                         break;
2150                 }
2151                 if ( $resetGzipEncoding ) {
2152                         if ( $status['name'] == 'ob_gzhandler' ) {
2153                                 // Reset the 'Content-Encoding' field set by this handler
2154                                 // so we can start fresh.
2155                                 header_remove( 'Content-Encoding' );
2156                                 break;
2157                         }
2158                 }
2159         }
2160 }
2161
2162 /**
2163  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
2164  *
2165  * Clear away output buffers, but keep the Content-Encoding header
2166  * produced by ob_gzhandler, if any.
2167  *
2168  * This should be used for HTTP 304 responses, where you need to
2169  * preserve the Content-Encoding header of the real result, but
2170  * also need to suppress the output of ob_gzhandler to keep to spec
2171  * and avoid breaking Firefox in rare cases where the headers and
2172  * body are broken over two packets.
2173  */
2174 function wfClearOutputBuffers() {
2175         wfResetOutputBuffers( false );
2176 }
2177
2178 /**
2179  * Converts an Accept-* header into an array mapping string values to quality
2180  * factors
2181  *
2182  * @param $accept String
2183  * @param string $def default
2184  * @return Array
2185  */
2186 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
2187         # No arg means accept anything (per HTTP spec)
2188         if ( !$accept ) {
2189                 return array( $def => 1.0 );
2190         }
2191
2192         $prefs = array();
2193
2194         $parts = explode( ',', $accept );
2195
2196         foreach ( $parts as $part ) {
2197                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
2198                 $values = explode( ';', trim( $part ) );
2199                 $match = array();
2200                 if ( count( $values ) == 1 ) {
2201                         $prefs[$values[0]] = 1.0;
2202                 } elseif ( preg_match( '/q\s*=\s*(\d*\.\d+)/', $values[1], $match ) ) {
2203                         $prefs[$values[0]] = floatval( $match[1] );
2204                 }
2205         }
2206
2207         return $prefs;
2208 }
2209
2210 /**
2211  * Checks if a given MIME type matches any of the keys in the given
2212  * array. Basic wildcards are accepted in the array keys.
2213  *
2214  * Returns the matching MIME type (or wildcard) if a match, otherwise
2215  * NULL if no match.
2216  *
2217  * @param $type String
2218  * @param $avail Array
2219  * @return string
2220  * @private
2221  */
2222 function mimeTypeMatch( $type, $avail ) {
2223         if ( array_key_exists( $type, $avail ) ) {
2224                 return $type;
2225         } else {
2226                 $parts = explode( '/', $type );
2227                 if ( array_key_exists( $parts[0] . '/*', $avail ) ) {
2228                         return $parts[0] . '/*';
2229                 } elseif ( array_key_exists( '*/*', $avail ) ) {
2230                         return '*/*';
2231                 } else {
2232                         return null;
2233                 }
2234         }
2235 }
2236
2237 /**
2238  * Returns the 'best' match between a client's requested internet media types
2239  * and the server's list of available types. Each list should be an associative
2240  * array of type to preference (preference is a float between 0.0 and 1.0).
2241  * Wildcards in the types are acceptable.
2242  *
2243  * @param array $cprefs client's acceptable type list
2244  * @param array $sprefs server's offered types
2245  * @return string
2246  *
2247  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
2248  * XXX: generalize to negotiate other stuff
2249  */
2250 function wfNegotiateType( $cprefs, $sprefs ) {
2251         $combine = array();
2252
2253         foreach ( array_keys( $sprefs ) as $type ) {
2254                 $parts = explode( '/', $type );
2255                 if ( $parts[1] != '*' ) {
2256                         $ckey = mimeTypeMatch( $type, $cprefs );
2257                         if ( $ckey ) {
2258                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
2259                         }
2260                 }
2261         }
2262
2263         foreach ( array_keys( $cprefs ) as $type ) {
2264                 $parts = explode( '/', $type );
2265                 if ( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
2266                         $skey = mimeTypeMatch( $type, $sprefs );
2267                         if ( $skey ) {
2268                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
2269                         }
2270                 }
2271         }
2272
2273         $bestq = 0;
2274         $besttype = null;
2275
2276         foreach ( array_keys( $combine ) as $type ) {
2277                 if ( $combine[$type] > $bestq ) {
2278                         $besttype = $type;
2279                         $bestq = $combine[$type];
2280                 }
2281         }
2282
2283         return $besttype;
2284 }
2285
2286 /**
2287  * Reference-counted warning suppression
2288  *
2289  * @param $end Bool
2290  */
2291 function wfSuppressWarnings( $end = false ) {
2292         static $suppressCount = 0;
2293         static $originalLevel = false;
2294
2295         if ( $end ) {
2296                 if ( $suppressCount ) {
2297                         --$suppressCount;
2298                         if ( !$suppressCount ) {
2299                                 error_reporting( $originalLevel );
2300                         }
2301                 }
2302         } else {
2303                 if ( !$suppressCount ) {
2304                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE | E_USER_WARNING | E_USER_NOTICE | E_DEPRECATED | E_USER_DEPRECATED | E_STRICT ) );
2305                 }
2306                 ++$suppressCount;
2307         }
2308 }
2309
2310 /**
2311  * Restore error level to previous value
2312  */
2313 function wfRestoreWarnings() {
2314         wfSuppressWarnings( true );
2315 }
2316
2317 # Autodetect, convert and provide timestamps of various types
2318
2319 /**
2320  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
2321  */
2322 define( 'TS_UNIX', 0 );
2323
2324 /**
2325  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
2326  */
2327 define( 'TS_MW', 1 );
2328
2329 /**
2330  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
2331  */
2332 define( 'TS_DB', 2 );
2333
2334 /**
2335  * RFC 2822 format, for E-mail and HTTP headers
2336  */
2337 define( 'TS_RFC2822', 3 );
2338
2339 /**
2340  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
2341  *
2342  * This is used by Special:Export
2343  */
2344 define( 'TS_ISO_8601', 4 );
2345
2346 /**
2347  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
2348  *
2349  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
2350  *       DateTime tag and page 36 for the DateTimeOriginal and
2351  *       DateTimeDigitized tags.
2352  */
2353 define( 'TS_EXIF', 5 );
2354
2355 /**
2356  * Oracle format time.
2357  */
2358 define( 'TS_ORACLE', 6 );
2359
2360 /**
2361  * Postgres format time.
2362  */
2363 define( 'TS_POSTGRES', 7 );
2364
2365 /**
2366  * ISO 8601 basic format with no timezone: 19860209T200000Z.  This is used by ResourceLoader
2367  */
2368 define( 'TS_ISO_8601_BASIC', 9 );
2369
2370 /**
2371  * Get a timestamp string in one of various formats
2372  *
2373  * @param $outputtype Mixed: A timestamp in one of the supported formats, the
2374  *                    function will autodetect which format is supplied and act
2375  *                    accordingly.
2376  * @param $ts Mixed: optional timestamp to convert, default 0 for the current time
2377  * @return Mixed: String / false The same date in the format specified in $outputtype or false
2378  */
2379 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
2380         try {
2381                 $timestamp = new MWTimestamp( $ts );
2382                 return $timestamp->getTimestamp( $outputtype );
2383         } catch ( TimestampException $e ) {
2384                 wfDebug( "wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n" );
2385                 return false;
2386         }
2387 }
2388
2389 /**
2390  * Return a formatted timestamp, or null if input is null.
2391  * For dealing with nullable timestamp columns in the database.
2392  *
2393  * @param $outputtype Integer
2394  * @param $ts String
2395  * @return String
2396  */
2397 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2398         if ( is_null( $ts ) ) {
2399                 return null;
2400         } else {
2401                 return wfTimestamp( $outputtype, $ts );
2402         }
2403 }
2404
2405 /**
2406  * Convenience function; returns MediaWiki timestamp for the present time.
2407  *
2408  * @return string
2409  */
2410 function wfTimestampNow() {
2411         # return NOW
2412         return wfTimestamp( TS_MW, time() );
2413 }
2414
2415 /**
2416  * Check if the operating system is Windows
2417  *
2418  * @return Bool: true if it's Windows, False otherwise.
2419  */
2420 function wfIsWindows() {
2421         static $isWindows = null;
2422         if ( $isWindows === null ) {
2423                 $isWindows = substr( php_uname(), 0, 7 ) == 'Windows';
2424         }
2425         return $isWindows;
2426 }
2427
2428 /**
2429  * Check if we are running under HipHop
2430  *
2431  * @return Bool
2432  */
2433 function wfIsHipHop() {
2434         return function_exists( 'hphp_thread_set_warmup_enabled' );
2435 }
2436
2437 /**
2438  * Swap two variables
2439  *
2440  * @param $x Mixed
2441  * @param $y Mixed
2442  */
2443 function swap( &$x, &$y ) {
2444         $z = $x;
2445         $x = $y;
2446         $y = $z;
2447 }
2448
2449 /**
2450  * Tries to get the system directory for temporary files. First
2451  * $wgTmpDirectory is checked, and then the TMPDIR, TMP, and TEMP
2452  * environment variables are then checked in sequence, and if none are
2453  * set try sys_get_temp_dir().
2454  *
2455  * NOTE: When possible, use instead the tmpfile() function to create
2456  * temporary files to avoid race conditions on file creation, etc.
2457  *
2458  * @return String
2459  */
2460 function wfTempDir() {
2461         global $wgTmpDirectory;
2462
2463         if ( $wgTmpDirectory !== false ) {
2464                 return $wgTmpDirectory;
2465         }
2466
2467         $tmpDir = array_map( "getenv", array( 'TMPDIR', 'TMP', 'TEMP' ) );
2468
2469         foreach ( $tmpDir as $tmp ) {
2470                 if ( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
2471                         return $tmp;
2472                 }
2473         }
2474         return sys_get_temp_dir();
2475 }
2476
2477 /**
2478  * Make directory, and make all parent directories if they don't exist
2479  *
2480  * @param string $dir full path to directory to create
2481  * @param $mode Integer: chmod value to use, default is $wgDirectoryMode
2482  * @param string $caller optional caller param for debugging.
2483  * @throws MWException
2484  * @return bool
2485  */
2486 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2487         global $wgDirectoryMode;
2488
2489         if ( FileBackend::isStoragePath( $dir ) ) { // sanity
2490                 throw new MWException( __FUNCTION__ . " given storage path '$dir'." );
2491         }
2492
2493         if ( !is_null( $caller ) ) {
2494                 wfDebug( "$caller: called wfMkdirParents($dir)\n" );
2495         }
2496
2497         if ( strval( $dir ) === '' || file_exists( $dir ) ) {
2498                 return true;
2499         }
2500
2501         $dir = str_replace( array( '\\', '/' ), DIRECTORY_SEPARATOR, $dir );
2502
2503         if ( is_null( $mode ) ) {
2504                 $mode = $wgDirectoryMode;
2505         }
2506
2507         // Turn off the normal warning, we're doing our own below
2508         wfSuppressWarnings();
2509         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2510         wfRestoreWarnings();
2511
2512         if ( !$ok ) {
2513                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2514                 wfLogWarning( sprintf( "failed to mkdir \"%s\" mode 0%o", $dir, $mode ) );
2515         }
2516         return $ok;
2517 }
2518
2519 /**
2520  * Remove a directory and all its content.
2521  * Does not hide error.
2522  */
2523 function wfRecursiveRemoveDir( $dir ) {
2524         wfDebug( __FUNCTION__ . "( $dir )\n" );
2525         // taken from http://de3.php.net/manual/en/function.rmdir.php#98622
2526         if ( is_dir( $dir ) ) {
2527                 $objects = scandir( $dir );
2528                 foreach ( $objects as $object ) {
2529                         if ( $object != "." && $object != ".." ) {
2530                                 if ( filetype( $dir . '/' . $object ) == "dir" ) {
2531                                         wfRecursiveRemoveDir( $dir . '/' . $object );
2532                                 } else {
2533                                         unlink( $dir . '/' . $object );
2534                                 }
2535                         }
2536                 }
2537                 reset( $objects );
2538                 rmdir( $dir );
2539         }
2540 }
2541
2542 /**
2543  * @param $nr Mixed: the number to format
2544  * @param $acc Integer: the number of digits after the decimal point, default 2
2545  * @param $round Boolean: whether or not to round the value, default true
2546  * @return float
2547  */
2548 function wfPercent( $nr, $acc = 2, $round = true ) {
2549         $ret = sprintf( "%.${acc}f", $nr );
2550         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2551 }
2552
2553 /**
2554  * Find out whether or not a mixed variable exists in a string
2555  *
2556  * @deprecated Just use str(i)pos
2557  * @param $needle String
2558  * @param $str String
2559  * @param $insensitive Boolean
2560  * @return Boolean
2561  */
2562 function in_string( $needle, $str, $insensitive = false ) {
2563         wfDeprecated( __METHOD__, '1.21' );
2564         $func = 'strpos';
2565         if ( $insensitive ) {
2566                 $func = 'stripos';
2567         }
2568
2569         return $func( $str, $needle ) !== false;
2570 }
2571
2572 /**
2573  * Safety wrapper around ini_get() for boolean settings.
2574  * The values returned from ini_get() are pre-normalized for settings
2575  * set via php.ini or php_flag/php_admin_flag... but *not*
2576  * for those set via php_value/php_admin_value.
2577  *
2578  * It's fairly common for people to use php_value instead of php_flag,
2579  * which can leave you with an 'off' setting giving a false positive
2580  * for code that just takes the ini_get() return value as a boolean.
2581  *
2582  * To make things extra interesting, setting via php_value accepts
2583  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2584  * Unrecognized values go false... again opposite PHP's own coercion
2585  * from string to bool.
2586  *
2587  * Luckily, 'properly' set settings will always come back as '0' or '1',
2588  * so we only have to worry about them and the 'improper' settings.
2589  *
2590  * I frickin' hate PHP... :P
2591  *
2592  * @param $setting String
2593  * @return Bool
2594  */
2595 function wfIniGetBool( $setting ) {
2596         $val = strtolower( ini_get( $setting ) );
2597         // 'on' and 'true' can't have whitespace around them, but '1' can.
2598         return $val == 'on'
2599                 || $val == 'true'
2600                 || $val == 'yes'
2601                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2602 }
2603
2604 /**
2605  * Wrapper function for PHP's dl(). This doesn't work in most situations from
2606  * PHP 5.3 onward, and is usually disabled in shared environments anyway.
2607  *
2608  * @param string $extension A PHP extension. The file suffix (.so or .dll)
2609  *                          should be omitted
2610  * @param string $fileName Name of the library, if not $extension.suffix
2611  * @return Bool - Whether or not the extension is loaded
2612  */
2613 function wfDl( $extension, $fileName = null ) {
2614         if ( extension_loaded( $extension ) ) {
2615                 return true;
2616         }
2617
2618         $canDl = false;
2619         if ( PHP_SAPI == 'cli' || PHP_SAPI == 'cgi' || PHP_SAPI == 'embed' ) {
2620                 $canDl = ( function_exists( 'dl' ) && is_callable( 'dl' )
2621                 && wfIniGetBool( 'enable_dl' ) && !wfIniGetBool( 'safe_mode' ) );
2622         }
2623
2624         if ( $canDl ) {
2625                 $fileName = $fileName ? $fileName : $extension;
2626                 if ( wfIsWindows() ) {
2627                         $fileName = 'php_' . $fileName;
2628                 }
2629                 wfSuppressWarnings();
2630                 dl( $fileName . '.' . PHP_SHLIB_SUFFIX );
2631                 wfRestoreWarnings();
2632         }
2633         return extension_loaded( $extension );
2634 }
2635
2636 /**
2637  * Windows-compatible version of escapeshellarg()
2638  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
2639  * function puts single quotes in regardless of OS.
2640  *
2641  * Also fixes the locale problems on Linux in PHP 5.2.6+ (bug backported to
2642  * earlier distro releases of PHP)
2643  *
2644  * @param varargs
2645  * @return String
2646  */
2647 function wfEscapeShellArg() {
2648         wfInitShellLocale();
2649
2650         $args = func_get_args();
2651         $first = true;
2652         $retVal = '';
2653         foreach ( $args as $arg ) {
2654                 if ( !$first ) {
2655                         $retVal .= ' ';
2656                 } else {
2657                         $first = false;
2658                 }
2659
2660                 if ( wfIsWindows() ) {
2661                         // Escaping for an MSVC-style command line parser and CMD.EXE
2662                         // Refs:
2663                         //  * http://web.archive.org/web/20020708081031/http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
2664                         //  * http://technet.microsoft.com/en-us/library/cc723564.aspx
2665                         //  * Bug #13518
2666                         //  * CR r63214
2667                         // Double the backslashes before any double quotes. Escape the double quotes.
2668                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
2669                         $arg = '';
2670                         $iteration = 0;
2671                         foreach ( $tokens as $token ) {
2672                                 if ( $iteration % 2 == 1 ) {
2673                                         // Delimiter, a double quote preceded by zero or more slashes
2674                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
2675                                 } elseif ( $iteration % 4 == 2 ) {
2676                                         // ^ in $token will be outside quotes, need to be escaped
2677                                         $arg .= str_replace( '^', '^^', $token );
2678                                 } else { // $iteration % 4 == 0
2679                                         // ^ in $token will appear inside double quotes, so leave as is
2680                                         $arg .= $token;
2681                                 }
2682                                 $iteration++;
2683                         }
2684                         // Double the backslashes before the end of the string, because
2685                         // we will soon add a quote
2686                         $m = array();
2687                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
2688                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
2689                         }
2690
2691                         // Add surrounding quotes
2692                         $retVal .= '"' . $arg . '"';
2693                 } else {
2694                         $retVal .= escapeshellarg( $arg );
2695                 }
2696         }
2697         return $retVal;
2698 }
2699
2700 /**
2701  * Check if wfShellExec() is effectively disabled via php.ini config
2702  * @return bool|string False or one of (safemode,disabled)
2703  * @since 1.22
2704  */
2705 function wfShellExecDisabled() {
2706         static $disabled = null;
2707         if ( is_null( $disabled ) ) {
2708                 $disabled = false;
2709                 if ( wfIniGetBool( 'safe_mode' ) ) {
2710                         wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
2711                         $disabled = 'safemode';
2712                 } else {
2713                         $functions = explode( ',', ini_get( 'disable_functions' ) );
2714                         $functions = array_map( 'trim', $functions );
2715                         $functions = array_map( 'strtolower', $functions );
2716                         if ( in_array( 'passthru', $functions ) ) {
2717                                 wfDebug( "passthru is in disabled_functions\n" );
2718                                 $disabled = 'passthru';
2719                         }
2720                 }
2721         }
2722         return $disabled;
2723 }
2724
2725 /**
2726  * Execute a shell command, with time and memory limits mirrored from the PHP
2727  * configuration if supported.
2728  * @param string $cmd Command line, properly escaped for shell.
2729  * @param &$retval null|Mixed optional, will receive the program's exit code.
2730  *                 (non-zero is usually failure)
2731  * @param array $environ optional environment variables which should be
2732  *                 added to the executed command environment.
2733  * @param array $limits optional array with limits(filesize, memory, time, walltime)
2734  *                 this overwrites the global wgShellMax* limits.
2735  * @return string collected stdout as a string (trailing newlines stripped)
2736  */
2737 function wfShellExec( $cmd, &$retval = null, $environ = array(), $limits = array() ) {
2738         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize, $wgMaxShellTime,
2739                 $wgMaxShellWallClockTime, $wgShellCgroup;
2740
2741         $disabled = wfShellExecDisabled();
2742         if ( $disabled ) {
2743                 $retval = 1;
2744                 return $disabled == 'safemode' ?
2745                         'Unable to run external programs in safe mode.' :
2746                         'Unable to run external programs, passthru() is disabled.';
2747         }
2748
2749         wfInitShellLocale();
2750
2751         $envcmd = '';
2752         foreach ( $environ as $k => $v ) {
2753                 if ( wfIsWindows() ) {
2754                         /* Surrounding a set in quotes (method used by wfEscapeShellArg) makes the quotes themselves
2755                          * appear in the environment variable, so we must use carat escaping as documented in
2756                          * http://technet.microsoft.com/en-us/library/cc723564.aspx
2757                          * Note however that the quote isn't listed there, but is needed, and the parentheses
2758                          * are listed there but doesn't appear to need it.
2759                          */
2760                         $envcmd .= "set $k=" . preg_replace( '/([&|()<>^"])/', '^\\1', $v ) . '&& ';
2761                 } else {
2762                         /* Assume this is a POSIX shell, thus required to accept variable assignments before the command
2763                          * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_09_01
2764                          */
2765                         $envcmd .= "$k=" . escapeshellarg( $v ) . ' ';
2766                 }
2767         }
2768         $cmd = $envcmd . $cmd;
2769
2770         if ( php_uname( 's' ) == 'Linux' ) {
2771                 $time = intval ( isset( $limits['time'] ) ? $limits['time'] : $wgMaxShellTime );
2772                 if ( isset( $limits['walltime'] ) ) {
2773                         $wallTime = intval( $limits['walltime'] );
2774                 } elseif ( isset( $limits['time'] ) ) {
2775                         $wallTime = $time;
2776                 } else {
2777                         $wallTime = intval( $wgMaxShellWallClockTime );
2778                 }
2779                 $mem = intval ( isset( $limits['memory'] ) ? $limits['memory'] : $wgMaxShellMemory );
2780                 $filesize = intval ( isset( $limits['filesize'] ) ? $limits['filesize'] : $wgMaxShellFileSize );
2781
2782                 if ( $time > 0 || $mem > 0 || $filesize > 0 || $wallTime > 0 ) {
2783                         $cmd = '/bin/bash ' . escapeshellarg( "$IP/includes/limit.sh" ) . ' ' .
2784                                 escapeshellarg( $cmd ) . ' ' .
2785                                 escapeshellarg(
2786                                         "MW_CPU_LIMIT=$time; " .
2787                                         'MW_CGROUP=' . escapeshellarg( $wgShellCgroup ) . '; ' .
2788                                         "MW_MEM_LIMIT=$mem; " .
2789                                         "MW_FILE_SIZE_LIMIT=$filesize; " .
2790                                         "MW_WALL_CLOCK_LIMIT=$wallTime"
2791                                 );
2792                 }
2793         }
2794         wfDebug( "wfShellExec: $cmd\n" );
2795
2796         $retval = 1; // error by default?
2797         ob_start();
2798         passthru( $cmd, $retval );
2799         $output = ob_get_contents();
2800         ob_end_clean();
2801
2802         if ( $retval == 127 ) {
2803                 wfDebugLog( 'exec', "Possibly missing executable file: $cmd\n" );
2804         }
2805         return $output;
2806 }
2807
2808 /**
2809  * Workaround for http://bugs.php.net/bug.php?id=45132
2810  * escapeshellarg() destroys non-ASCII characters if LANG is not a UTF-8 locale
2811  */
2812 function wfInitShellLocale() {
2813         static $done = false;
2814         if ( $done ) {
2815                 return;
2816         }
2817         $done = true;
2818         global $wgShellLocale;
2819         if ( !wfIniGetBool( 'safe_mode' ) ) {
2820                 putenv( "LC_CTYPE=$wgShellLocale" );
2821                 setlocale( LC_CTYPE, $wgShellLocale );
2822         }
2823 }
2824
2825 /**
2826  * Alias to wfShellWikiCmd()
2827  * @see wfShellWikiCmd()
2828  */
2829 function wfShellMaintenanceCmd( $script, array $parameters = array(), array $options = array() ) {
2830         return wfShellWikiCmd( $script, $parameters, $options );
2831 }
2832
2833 /**
2834  * Generate a shell-escaped command line string to run a MediaWiki cli script.
2835  * Note that $parameters should be a flat array and an option with an argument
2836  * should consist of two consecutive items in the array (do not use "--option value").
2837  * @param string $script MediaWiki cli script path
2838  * @param array $parameters Arguments and options to the script
2839  * @param array $options Associative array of options:
2840  *              'php': The path to the php executable
2841  *              'wrapper': Path to a PHP wrapper to handle the maintenance script
2842  * @return Array
2843  */
2844 function wfShellWikiCmd( $script, array $parameters = array(), array $options = array() ) {
2845         global $wgPhpCli;
2846         // Give site config file a chance to run the script in a wrapper.
2847         // The caller may likely want to call wfBasename() on $script.
2848         wfRunHooks( 'wfShellWikiCmd', array( &$script, &$parameters, &$options ) );
2849         $cmd = isset( $options['php'] ) ? array( $options['php'] ) : array( $wgPhpCli );
2850         if ( isset( $options['wrapper'] ) ) {
2851                 $cmd[] = $options['wrapper'];
2852         }
2853         $cmd[] = $script;
2854         // Escape each parameter for shell
2855         return implode( " ", array_map( 'wfEscapeShellArg', array_merge( $cmd, $parameters ) ) );
2856 }
2857
2858 /**
2859  * wfMerge attempts to merge differences between three texts.
2860  * Returns true for a clean merge and false for failure or a conflict.
2861  *
2862  * @param $old String
2863  * @param $mine String
2864  * @param $yours String
2865  * @param $result String
2866  * @return Bool
2867  */
2868 function wfMerge( $old, $mine, $yours, &$result ) {
2869         global $wgDiff3;
2870
2871         # This check may also protect against code injection in
2872         # case of broken installations.
2873         wfSuppressWarnings();
2874         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
2875         wfRestoreWarnings();
2876
2877         if ( !$haveDiff3 ) {
2878                 wfDebug( "diff3 not found\n" );
2879                 return false;
2880         }
2881
2882         # Make temporary files
2883         $td = wfTempDir();
2884         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
2885         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
2886         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
2887
2888         # NOTE: diff3 issues a warning to stderr if any of the files does not end with
2889         #       a newline character. To avoid this, we normalize the trailing whitespace before
2890         #       creating the diff.
2891
2892         fwrite( $oldtextFile, rtrim( $old ) . "\n" );
2893         fclose( $oldtextFile );
2894         fwrite( $mytextFile, rtrim( $mine ) . "\n" );
2895         fclose( $mytextFile );
2896         fwrite( $yourtextFile, rtrim( $yours ) . "\n" );
2897         fclose( $yourtextFile );
2898
2899         # Check for a conflict
2900         $cmd = wfEscapeShellArg( $wgDiff3 ) . ' -a --overlap-only ' .
2901                 wfEscapeShellArg( $mytextName ) . ' ' .
2902                 wfEscapeShellArg( $oldtextName ) . ' ' .
2903                 wfEscapeShellArg( $yourtextName );
2904         $handle = popen( $cmd, 'r' );
2905
2906         if ( fgets( $handle, 1024 ) ) {
2907                 $conflict = true;
2908         } else {
2909                 $conflict = false;
2910         }
2911         pclose( $handle );
2912
2913         # Merge differences
2914         $cmd = wfEscapeShellArg( $wgDiff3 ) . ' -a -e --merge ' .
2915                 wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
2916         $handle = popen( $cmd, 'r' );
2917         $result = '';
2918         do {
2919                 $data = fread( $handle, 8192 );
2920                 if ( strlen( $data ) == 0 ) {
2921                         break;
2922                 }
2923                 $result .= $data;
2924         } while ( true );
2925         pclose( $handle );
2926         unlink( $mytextName );
2927         unlink( $oldtextName );
2928         unlink( $yourtextName );
2929
2930         if ( $result === '' && $old !== '' && !$conflict ) {
2931                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
2932                 $conflict = true;
2933         }
2934         return !$conflict;
2935 }
2936
2937 /**
2938  * Returns unified plain-text diff of two texts.
2939  * Useful for machine processing of diffs.
2940  *
2941  * @param string $before the text before the changes.
2942  * @param string $after the text after the changes.
2943  * @param string $params command-line options for the diff command.
2944  * @return String: unified diff of $before and $after
2945  */
2946 function wfDiff( $before, $after, $params = '-u' ) {
2947         if ( $before == $after ) {
2948                 return '';
2949         }
2950
2951         global $wgDiff;
2952         wfSuppressWarnings();
2953         $haveDiff = $wgDiff && file_exists( $wgDiff );
2954         wfRestoreWarnings();
2955
2956         # This check may also protect against code injection in
2957         # case of broken installations.
2958         if ( !$haveDiff ) {
2959                 wfDebug( "diff executable not found\n" );
2960                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
2961                 $format = new UnifiedDiffFormatter();
2962                 return $format->format( $diffs );
2963         }
2964
2965         # Make temporary files
2966         $td = wfTempDir();
2967         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
2968         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
2969
2970         fwrite( $oldtextFile, $before );
2971         fclose( $oldtextFile );
2972         fwrite( $newtextFile, $after );
2973         fclose( $newtextFile );
2974
2975         // Get the diff of the two files
2976         $cmd = "$wgDiff " . $params . ' ' . wfEscapeShellArg( $oldtextName, $newtextName );
2977
2978         $h = popen( $cmd, 'r' );
2979
2980         $diff = '';
2981
2982         do {
2983                 $data = fread( $h, 8192 );
2984                 if ( strlen( $data ) == 0 ) {
2985                         break;
2986                 }
2987                 $diff .= $data;
2988         } while ( true );
2989
2990         // Clean up
2991         pclose( $h );
2992         unlink( $oldtextName );
2993         unlink( $newtextName );
2994
2995         // Kill the --- and +++ lines. They're not useful.
2996         $diff_lines = explode( "\n", $diff );
2997         if ( strpos( $diff_lines[0], '---' ) === 0 ) {
2998                 unset( $diff_lines[0] );
2999         }
3000         if ( strpos( $diff_lines[1], '+++' ) === 0 ) {
3001                 unset( $diff_lines[1] );
3002         }
3003
3004         $diff = implode( "\n", $diff_lines );
3005
3006         return $diff;
3007 }
3008
3009 /**
3010  * This function works like "use VERSION" in Perl, the program will die with a
3011  * backtrace if the current version of PHP is less than the version provided
3012  *
3013  * This is useful for extensions which due to their nature are not kept in sync
3014  * with releases, and might depend on other versions of PHP than the main code
3015  *
3016  * Note: PHP might die due to parsing errors in some cases before it ever
3017  *       manages to call this function, such is life
3018  *
3019  * @see perldoc -f use
3020  *
3021  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
3022  *                 a float
3023  * @throws MWException
3024  */
3025 function wfUsePHP( $req_ver ) {
3026         $php_ver = PHP_VERSION;
3027
3028         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
3029                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
3030         }
3031 }
3032
3033 /**
3034  * This function works like "use VERSION" in Perl except it checks the version
3035  * of MediaWiki, the program will die with a backtrace if the current version
3036  * of MediaWiki is less than the version provided.
3037  *
3038  * This is useful for extensions which due to their nature are not kept in sync
3039  * with releases
3040  *
3041  * @see perldoc -f use
3042  *
3043  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
3044  *                 a float
3045  * @throws MWException
3046  */
3047 function wfUseMW( $req_ver ) {
3048         global $wgVersion;
3049
3050         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
3051                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
3052         }
3053 }
3054
3055 /**
3056  * Return the final portion of a pathname.
3057  * Reimplemented because PHP5's "basename()" is buggy with multibyte text.
3058  * http://bugs.php.net/bug.php?id=33898
3059  *
3060  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
3061  * We'll consider it so always, as we don't want '\s' in our Unix paths either.
3062  *
3063  * @param $path String
3064  * @param string $suffix to remove if present
3065  * @return String
3066  */
3067 function wfBaseName( $path, $suffix = '' ) {
3068         $encSuffix = ( $suffix == '' )
3069                 ? ''
3070                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
3071         $matches = array();
3072         if ( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
3073                 return $matches[1];
3074         } else {
3075                 return '';
3076         }
3077 }
3078
3079 /**
3080  * Generate a relative path name to the given file.
3081  * May explode on non-matching case-insensitive paths,
3082  * funky symlinks, etc.
3083  *
3084  * @param string $path absolute destination path including target filename
3085  * @param string $from Absolute source path, directory only
3086  * @return String
3087  */
3088 function wfRelativePath( $path, $from ) {
3089         // Normalize mixed input on Windows...
3090         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
3091         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
3092
3093         // Trim trailing slashes -- fix for drive root
3094         $path = rtrim( $path, DIRECTORY_SEPARATOR );
3095         $from = rtrim( $from, DIRECTORY_SEPARATOR );
3096
3097         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
3098         $against = explode( DIRECTORY_SEPARATOR, $from );
3099
3100         if ( $pieces[0] !== $against[0] ) {
3101                 // Non-matching Windows drive letters?
3102                 // Return a full path.
3103                 return $path;
3104         }
3105
3106         // Trim off common prefix
3107         while ( count( $pieces ) && count( $against )
3108                 && $pieces[0] == $against[0] ) {
3109                 array_shift( $pieces );
3110                 array_shift( $against );
3111         }
3112
3113         // relative dots to bump us to the parent
3114         while ( count( $against ) ) {
3115                 array_unshift( $pieces, '..' );
3116                 array_shift( $against );
3117         }
3118
3119         array_push( $pieces, wfBaseName( $path ) );
3120
3121         return implode( DIRECTORY_SEPARATOR, $pieces );
3122 }
3123
3124 /**
3125  * Do any deferred updates and clear the list
3126  *
3127  * @deprecated since 1.19
3128  * @see DeferredUpdates::doUpdate()
3129  * @param $commit string
3130  */
3131 function wfDoUpdates( $commit = '' ) {
3132         wfDeprecated( __METHOD__, '1.19' );
3133         DeferredUpdates::doUpdates( $commit );
3134 }
3135
3136 /**
3137  * Convert an arbitrarily-long digit string from one numeric base
3138  * to another, optionally zero-padding to a minimum column width.
3139  *
3140  * Supports base 2 through 36; digit values 10-36 are represented
3141  * as lowercase letters a-z. Input is case-insensitive.
3142  *
3143  * @param string $input Input number
3144  * @param int $sourceBase Base of the input number
3145  * @param int $destBase Desired base of the output
3146  * @param int $pad Minimum number of digits in the output (pad with zeroes)
3147  * @param bool $lowercase Whether to output in lowercase or uppercase
3148  * @param string $engine Either "gmp", "bcmath", or "php"
3149  * @return string|bool The output number as a string, or false on error
3150  */
3151 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1, $lowercase = true, $engine = 'auto' ) {
3152         $input = (string)$input;
3153         if (
3154                 $sourceBase < 2 ||
3155                 $sourceBase > 36 ||
3156                 $destBase < 2 ||
3157                 $destBase > 36 ||
3158                 $sourceBase != (int) $sourceBase ||
3159                 $destBase != (int) $destBase ||
3160                 $pad != (int) $pad ||
3161                 !preg_match( "/^[" . substr( '0123456789abcdefghijklmnopqrstuvwxyz', 0, $sourceBase ) . "]+$/i", $input )
3162         ) {
3163                 return false;
3164         }
3165
3166         static $baseChars = array(
3167                 10 => 'a', 11 => 'b', 12 => 'c', 13 => 'd', 14 => 'e', 15 => 'f',
3168                 16 => 'g', 17 => 'h', 18 => 'i', 19 => 'j', 20 => 'k', 21 => 'l',
3169                 22 => 'm', 23 => 'n', 24 => 'o', 25 => 'p', 26 => 'q', 27 => 'r',
3170                 28 => 's', 29 => 't', 30 => 'u', 31 => 'v', 32 => 'w', 33 => 'x',
3171                 34 => 'y', 35 => 'z',
3172
3173                 '0' => 0,  '1' => 1,  '2' => 2,  '3' => 3,  '4' => 4,  '5' => 5,
3174                 '6' => 6,  '7' => 7,  '8' => 8,  '9' => 9,  'a' => 10, 'b' => 11,
3175                 'c' => 12, 'd' => 13, 'e' => 14, 'f' => 15, 'g' => 16, 'h' => 17,
3176                 'i' => 18, 'j' => 19, 'k' => 20, 'l' => 21, 'm' => 22, 'n' => 23,
3177                 'o' => 24, 'p' => 25, 'q' => 26, 'r' => 27, 's' => 28, 't' => 29,
3178                 'u' => 30, 'v' => 31, 'w' => 32, 'x' => 33, 'y' => 34, 'z' => 35
3179         );
3180
3181         if ( extension_loaded( 'gmp' ) && ( $engine == 'auto' || $engine == 'gmp' ) ) {
3182                 $result = gmp_strval( gmp_init( $input, $sourceBase ), $destBase );
3183         } elseif ( extension_loaded( 'bcmath' ) && ( $engine == 'auto' || $engine == 'bcmath' ) ) {
3184                 $decimal = '0';
3185                 foreach ( str_split( strtolower( $input ) ) as $char ) {
3186                         $decimal = bcmul( $decimal, $sourceBase );
3187                         $decimal = bcadd( $decimal, $baseChars[$char] );
3188                 }
3189
3190                 for ( $result = ''; bccomp( $decimal, 0 ); $decimal = bcdiv( $decimal, $destBase, 0 ) ) {
3191                         $result .= $baseChars[bcmod( $decimal, $destBase )];
3192                 }
3193
3194                 $result = strrev( $result );
3195         } else {
3196                 $inDigits = array();
3197                 foreach ( str_split( strtolower( $input ) ) as $char ) {
3198                         $inDigits[] = $baseChars[$char];
3199                 }
3200
3201                 // Iterate over the input, modulo-ing out an output digit
3202                 // at a time until input is gone.
3203                 $result = '';
3204                 while ( $inDigits ) {
3205                         $work = 0;
3206                         $workDigits = array();
3207
3208                         // Long division...
3209                         foreach ( $inDigits as $digit ) {
3210                                 $work *= $sourceBase;
3211                                 $work += $digit;
3212
3213                                 if ( $workDigits || $work >= $destBase ) {
3214                                         $workDigits[] = (int) ( $work / $destBase );
3215                                 }
3216                                 $work %= $destBase;
3217                         }
3218
3219                         // All that division leaves us with a remainder,
3220                         // which is conveniently our next output digit.
3221                         $result .= $baseChars[$work];
3222
3223                         // And we continue!
3224                         $inDigits = $workDigits;
3225                 }
3226
3227                 $result = strrev( $result );
3228         }
3229
3230         if ( !$lowercase ) {
3231                 $result = strtoupper( $result );
3232         }
3233
3234         return str_pad( $result, $pad, '0', STR_PAD_LEFT );
3235 }
3236
3237 /**
3238  * Create an object with a given name and an array of construct parameters
3239  *
3240  * @param $name String
3241  * @param array $p parameters
3242  * @return object
3243  * @deprecated since 1.18, warnings in 1.18, removal in 1.20
3244  */
3245 function wfCreateObject( $name, $p ) {
3246         wfDeprecated( __FUNCTION__, '1.18' );
3247         return MWFunction::newObj( $name, $p );
3248 }
3249
3250 /**
3251  * @return bool
3252  */
3253 function wfHttpOnlySafe() {
3254         global $wgHttpOnlyBlacklist;
3255
3256         if ( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
3257                 foreach ( $wgHttpOnlyBlacklist as $regex ) {
3258                         if ( preg_match( $regex, $_SERVER['HTTP_USER_AGENT'] ) ) {
3259                                 return false;
3260                         }
3261                 }
3262         }
3263
3264         return true;
3265 }
3266
3267 /**
3268  * Check if there is sufficient entropy in php's built-in session generation
3269  * @return bool true = there is sufficient entropy
3270  */
3271 function wfCheckEntropy() {
3272         return (
3273                         ( wfIsWindows() && version_compare( PHP_VERSION, '5.3.3', '>=' ) )
3274                         || ini_get( 'session.entropy_file' )
3275                 )
3276                 && intval( ini_get( 'session.entropy_length' ) ) >= 32;
3277 }
3278
3279 /**
3280  * Override session_id before session startup if php's built-in
3281  * session generation code is not secure.
3282  */
3283 function wfFixSessionID() {
3284         // If the cookie or session id is already set we already have a session and should abort
3285         if ( isset( $_COOKIE[session_name()] ) || session_id() ) {
3286                 return;
3287         }
3288
3289         // PHP's built-in session entropy is enabled if:
3290         // - entropy_file is set or you're on Windows with php 5.3.3+
3291         // - AND entropy_length is > 0
3292         // We treat it as disabled if it doesn't have an entropy length of at least 32
3293         $entropyEnabled = wfCheckEntropy();
3294
3295         // If built-in entropy is not enabled or not sufficient override php's built in session id generation code
3296         if ( !$entropyEnabled ) {
3297                 wfDebug( __METHOD__ . ": PHP's built in entropy is disabled or not sufficient, overriding session id generation using our cryptrand source.\n" );
3298                 session_id( MWCryptRand::generateHex( 32 ) );
3299         }
3300 }
3301
3302 /**
3303  * Initialise php session
3304  *
3305  * @param $sessionId Bool
3306  */
3307 function wfSetupSession( $sessionId = false ) {
3308         global $wgSessionsInMemcached, $wgSessionsInObjectCache, $wgCookiePath, $wgCookieDomain,
3309                         $wgCookieSecure, $wgCookieHttpOnly, $wgSessionHandler;
3310         if ( $wgSessionsInObjectCache || $wgSessionsInMemcached ) {
3311                 ObjectCacheSessionHandler::install();
3312         } elseif ( $wgSessionHandler && $wgSessionHandler != ini_get( 'session.save_handler' ) ) {
3313                 # Only set this if $wgSessionHandler isn't null and session.save_handler
3314                 # hasn't already been set to the desired value (that causes errors)
3315                 ini_set( 'session.save_handler', $wgSessionHandler );
3316         }
3317         $httpOnlySafe = wfHttpOnlySafe() && $wgCookieHttpOnly;
3318         wfDebugLog( 'cookie',
3319                 'session_set_cookie_params: "' . implode( '", "',
3320                         array(
3321                                 0,
3322                                 $wgCookiePath,
3323                                 $wgCookieDomain,
3324                                 $wgCookieSecure,
3325                                 $httpOnlySafe ) ) . '"' );
3326         session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $httpOnlySafe );
3327         session_cache_limiter( 'private, must-revalidate' );
3328         if ( $sessionId ) {
3329                 session_id( $sessionId );
3330         } else {
3331                 wfFixSessionID();
3332         }
3333         wfSuppressWarnings();
3334         session_start();
3335         wfRestoreWarnings();
3336 }
3337
3338 /**
3339  * Get an object from the precompiled serialized directory
3340  *
3341  * @param $name String
3342  * @return Mixed: the variable on success, false on failure
3343  */
3344 function wfGetPrecompiledData( $name ) {
3345         global $IP;
3346
3347         $file = "$IP/serialized/$name";
3348         if ( file_exists( $file ) ) {
3349                 $blob = file_get_contents( $file );
3350                 if ( $blob ) {
3351                         return unserialize( $blob );
3352                 }
3353         }
3354         return false;
3355 }
3356
3357 /**
3358  * Get a cache key
3359  *
3360  * @param varargs
3361  * @return String
3362  */
3363 function wfMemcKey( /*... */ ) {
3364         global $wgCachePrefix;
3365         $prefix = $wgCachePrefix === false ? wfWikiID() : $wgCachePrefix;
3366         $args = func_get_args();
3367         $key = $prefix . ':' . implode( ':', $args );
3368         $key = str_replace( ' ', '_', $key );
3369         return $key;
3370 }
3371
3372 /**
3373  * Get a cache key for a foreign DB
3374  *
3375  * @param $db String
3376  * @param $prefix String
3377  * @param varargs String
3378  * @return String
3379  */
3380 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
3381         $args = array_slice( func_get_args(), 2 );
3382         if ( $prefix ) {
3383                 $key = "$db-$prefix:" . implode( ':', $args );
3384         } else {
3385                 $key = $db . ':' . implode( ':', $args );
3386         }
3387         return str_replace( ' ', '_', $key );
3388 }
3389
3390 /**
3391  * Get an ASCII string identifying this wiki
3392  * This is used as a prefix in memcached keys
3393  *
3394  * @return String
3395  */
3396 function wfWikiID() {
3397         global $wgDBprefix, $wgDBname;
3398         if ( $wgDBprefix ) {
3399                 return "$wgDBname-$wgDBprefix";
3400         } else {
3401                 return $wgDBname;
3402         }
3403 }
3404
3405 /**
3406  * Split a wiki ID into DB name and table prefix
3407  *
3408  * @param $wiki String
3409  *
3410  * @return array
3411  */
3412 function wfSplitWikiID( $wiki ) {
3413         $bits = explode( '-', $wiki, 2 );
3414         if ( count( $bits ) < 2 ) {
3415                 $bits[] = '';
3416         }
3417         return $bits;
3418 }
3419
3420 /**
3421  * Get a Database object.
3422  *
3423  * @param $db Integer: index of the connection to get. May be DB_MASTER for the
3424  *            master (for write queries), DB_SLAVE for potentially lagged read
3425  *            queries, or an integer >= 0 for a particular server.
3426  *
3427  * @param $groups Mixed: query groups. An array of group names that this query
3428  *                belongs to. May contain a single string if the query is only
3429  *                in one group.
3430  *
3431  * @param string $wiki the wiki ID, or false for the current wiki
3432  *
3433  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
3434  * will always return the same object, unless the underlying connection or load
3435  * balancer is manually destroyed.
3436  *
3437  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
3438  * updater to ensure that a proper database is being updated.
3439  *
3440  * @return DatabaseBase
3441  */
3442 function &wfGetDB( $db, $groups = array(), $wiki = false ) {
3443         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
3444 }
3445
3446 /**
3447  * Get a load balancer object.
3448  *
3449  * @param string $wiki wiki ID, or false for the current wiki
3450  * @return LoadBalancer
3451  */
3452 function wfGetLB( $wiki = false ) {
3453         return wfGetLBFactory()->getMainLB( $wiki );
3454 }
3455
3456 /**
3457  * Get the load balancer factory object
3458  *
3459  * @return LBFactory
3460  */
3461 function &wfGetLBFactory() {
3462         return LBFactory::singleton();
3463 }
3464
3465 /**
3466  * Find a file.
3467  * Shortcut for RepoGroup::singleton()->findFile()
3468  *
3469  * @param string $title or Title object
3470  * @param array $options Associative array of options:
3471  *     time:           requested time for an archived image, or false for the
3472  *                     current version. An image object will be returned which was
3473  *                     created at the specified time.
3474  *
3475  *     ignoreRedirect: If true, do not follow file redirects
3476  *
3477  *     private:        If true, return restricted (deleted) files if the current
3478  *                     user is allowed to view them. Otherwise, such files will not
3479  *                     be found.
3480  *
3481  *     bypassCache:    If true, do not use the process-local cache of File objects
3482  *
3483  * @return File, or false if the file does not exist
3484  */
3485 function wfFindFile( $title, $options = array() ) {
3486         return RepoGroup::singleton()->findFile( $title, $options );
3487 }
3488
3489 /**
3490  * Get an object referring to a locally registered file.
3491  * Returns a valid placeholder object if the file does not exist.
3492  *
3493  * @param $title Title|String
3494  * @return LocalFile|null A File, or null if passed an invalid Title
3495  */
3496 function wfLocalFile( $title ) {
3497         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
3498 }
3499
3500 /**
3501  * Stream a file to the browser. Back-compat alias for StreamFile::stream()
3502  * @deprecated since 1.19
3503  */
3504 function wfStreamFile( $fname, $headers = array() ) {
3505         wfDeprecated( __FUNCTION__, '1.19' );
3506         StreamFile::stream( $fname, $headers );
3507 }
3508
3509 /**
3510  * Should low-performance queries be disabled?
3511  *
3512  * @return Boolean
3513  * @codeCoverageIgnore
3514  */
3515 function wfQueriesMustScale() {
3516         global $wgMiserMode;
3517         return $wgMiserMode
3518                 || ( SiteStats::pages() > 100000
3519                 && SiteStats::edits() > 1000000
3520                 && SiteStats::users() > 10000 );
3521 }
3522
3523 /**
3524  * Get the path to a specified script file, respecting file
3525  * extensions; this is a wrapper around $wgScriptExtension etc.
3526  * except for 'index' and 'load' which use $wgScript/$wgLoadScript
3527  *
3528  * @param string $script script filename, sans extension
3529  * @return String
3530  */
3531 function wfScript( $script = 'index' ) {
3532         global $wgScriptPath, $wgScriptExtension, $wgScript, $wgLoadScript;
3533         if ( $script === 'index' ) {
3534                 return $wgScript;
3535         } elseif ( $script === 'load' ) {
3536                 return $wgLoadScript;
3537         } else {
3538                 return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
3539         }
3540 }
3541
3542 /**
3543  * Get the script URL.
3544  *
3545  * @return string script URL
3546  */
3547 function wfGetScriptUrl() {
3548         if ( isset( $_SERVER['SCRIPT_NAME'] ) ) {
3549                 #
3550                 # as it was called, minus the query string.
3551                 #
3552                 # Some sites use Apache rewrite rules to handle subdomains,
3553                 # and have PHP set up in a weird way that causes PHP_SELF
3554                 # to contain the rewritten URL instead of the one that the
3555                 # outside world sees.
3556                 #
3557                 # If in this mode, use SCRIPT_URL instead, which mod_rewrite
3558                 # provides containing the "before" URL.
3559                 return $_SERVER['SCRIPT_NAME'];
3560         } else {
3561                 return $_SERVER['URL'];
3562         }
3563 }
3564
3565 /**
3566  * Convenience function converts boolean values into "true"
3567  * or "false" (string) values
3568  *
3569  * @param $value Boolean
3570  * @return String
3571  */
3572 function wfBoolToStr( $value ) {
3573         return $value ? 'true' : 'false';
3574 }
3575
3576 /**
3577  * Get a platform-independent path to the null file, e.g. /dev/null
3578  *
3579  * @return string
3580  */
3581 function wfGetNull() {
3582         return wfIsWindows()
3583                 ? 'NUL'
3584                 : '/dev/null';
3585 }
3586
3587 /**
3588  * Modern version of wfWaitForSlaves(). Instead of looking at replication lag
3589  * and waiting for it to go down, this waits for the slaves to catch up to the
3590  * master position. Use this when updating very large numbers of rows, as
3591  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
3592  * a no-op if there are no slaves.
3593  *
3594  * @param $maxLag Integer (deprecated)
3595  * @param $wiki mixed Wiki identifier accepted by wfGetLB
3596  * @param $cluster string cluster name accepted by LBFactory
3597  */
3598 function wfWaitForSlaves( $maxLag = false, $wiki = false, $cluster = false ) {
3599         $lb = ( $cluster !== false )
3600                 ? wfGetLBFactory()->getExternalLB( $cluster )
3601                 : wfGetLB( $wiki );
3602         // bug 27975 - Don't try to wait for slaves if there are none
3603         // Prevents permission error when getting master position
3604         if ( $lb->getServerCount() > 1 ) {
3605                 $dbw = $lb->getConnection( DB_MASTER, array(), $wiki );
3606                 $pos = $dbw->getMasterPos();
3607                 // The DBMS may not support getMasterPos() or the whole
3608                 // load balancer might be fake (e.g. $wgAllDBsAreLocalhost).
3609                 if ( $pos !== false ) {
3610                         $lb->waitForAll( $pos );
3611                 }
3612         }
3613 }
3614
3615 /**
3616  * Used to be used for outputting text in the installer/updater
3617  * @deprecated since 1.18, warnings in 1.18, remove in 1.20
3618  */
3619 function wfOut( $s ) {
3620         wfDeprecated( __FUNCTION__, '1.18' );
3621         global $wgCommandLineMode;
3622         if ( $wgCommandLineMode ) {
3623                 echo $s;
3624         } else {
3625                 echo htmlspecialchars( $s );
3626         }
3627         flush();
3628 }
3629
3630 /**
3631  * Count down from $n to zero on the terminal, with a one-second pause
3632  * between showing each number. For use in command-line scripts.
3633  * @codeCoverageIgnore
3634  * @param $n int
3635  */
3636 function wfCountDown( $n ) {
3637         for ( $i = $n; $i >= 0; $i-- ) {
3638                 if ( $i != $n ) {
3639                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3640                 }
3641                 echo $i;
3642                 flush();
3643                 if ( $i ) {
3644                         sleep( 1 );
3645                 }
3646         }
3647         echo "\n";
3648 }
3649
3650 /**
3651  * Generate a random 32-character hexadecimal token.
3652  * @param $salt Mixed: some sort of salt, if necessary, to add to random
3653  *              characters before hashing.
3654  * @return string
3655  * @codeCoverageIgnore
3656  * @deprecated since 1.20; Please use MWCryptRand for security purposes and wfRandomString for pseudo-random strings
3657  * @warning This method is NOT secure. Additionally it has many callers that use it for pseudo-random purposes.
3658  */
3659 function wfGenerateToken( $salt = '' ) {
3660         wfDeprecated( __METHOD__, '1.20' );
3661         $salt = serialize( $salt );
3662         return md5( mt_rand( 0, 0x7fffffff ) . $salt );
3663 }
3664
3665 /**
3666  * Replace all invalid characters with -
3667  * Additional characters can be defined in $wgIllegalFileChars (see bug 20489)
3668  * By default, $wgIllegalFileChars = ':'
3669  *
3670  * @param $name Mixed: filename to process
3671  * @return String
3672  */
3673 function wfStripIllegalFilenameChars( $name ) {
3674         global $wgIllegalFileChars;
3675         $illegalFileChars = $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '';
3676         $name = wfBaseName( $name );
3677         $name = preg_replace(
3678                 "/[^" . Title::legalChars() . "]" . $illegalFileChars . "/",
3679                 '-',
3680                 $name
3681         );
3682         return $name;
3683 }
3684
3685 /**
3686  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit;
3687  *
3688  * @return Integer value memory was set to.
3689  */
3690 function wfMemoryLimit() {
3691         global $wgMemoryLimit;
3692         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3693         if ( $memlimit != -1 ) {
3694                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3695                 if ( $conflimit == -1 ) {
3696                         wfDebug( "Removing PHP's memory limit\n" );
3697                         wfSuppressWarnings();
3698                         ini_set( 'memory_limit', $conflimit );
3699                         wfRestoreWarnings();
3700                         return $conflimit;
3701                 } elseif ( $conflimit > $memlimit ) {
3702                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3703                         wfSuppressWarnings();
3704                         ini_set( 'memory_limit', $conflimit );
3705                         wfRestoreWarnings();
3706                         return $conflimit;
3707                 }
3708         }
3709         return $memlimit;
3710 }
3711
3712 /**
3713  * Converts shorthand byte notation to integer form
3714  *
3715  * @param $string String
3716  * @return Integer
3717  */
3718 function wfShorthandToInteger( $string = '' ) {
3719         $string = trim( $string );
3720         if ( $string === '' ) {
3721                 return -1;
3722         }
3723         $last = $string[strlen( $string ) - 1];
3724         $val = intval( $string );
3725         switch ( $last ) {
3726                 case 'g':
3727                 case 'G':
3728                         $val *= 1024;
3729                         // break intentionally missing
3730                 case 'm':
3731                 case 'M':
3732                         $val *= 1024;
3733                         // break intentionally missing
3734                 case 'k':
3735                 case 'K':
3736                         $val *= 1024;
3737         }
3738
3739         return $val;
3740 }
3741
3742 /**
3743  * Get the normalised IETF language tag
3744  * See unit test for examples.
3745  *
3746  * @param string $code The language code.
3747  * @return String: The language code which complying with BCP 47 standards.
3748  */
3749 function wfBCP47( $code ) {
3750         $codeSegment = explode( '-', $code );
3751         $codeBCP = array();
3752         foreach ( $codeSegment as $segNo => $seg ) {
3753                 if ( count( $codeSegment ) > 0 ) {
3754                         // when previous segment is x, it is a private segment and should be lc
3755                         if ( $segNo > 0 && strtolower( $codeSegment[( $segNo - 1 )] ) == 'x' ) {
3756                                 $codeBCP[$segNo] = strtolower( $seg );
3757                         // ISO 3166 country code
3758                         } elseif ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3759                                 $codeBCP[$segNo] = strtoupper( $seg );
3760                         // ISO 15924 script code
3761                         } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3762                                 $codeBCP[$segNo] = ucfirst( strtolower( $seg ) );
3763                         // Use lowercase for other cases
3764                         } else {
3765                                 $codeBCP[$segNo] = strtolower( $seg );
3766                         }
3767                 } else {
3768                 // Use lowercase for single segment
3769                         $codeBCP[$segNo] = strtolower( $seg );
3770                 }
3771         }
3772         $langCode = implode( '-', $codeBCP );
3773         return $langCode;
3774 }
3775
3776 /**
3777  * Get a cache object.
3778  *
3779  * @param $inputType integer Cache type, one the the CACHE_* constants.
3780  * @return BagOStuff
3781  */
3782 function wfGetCache( $inputType ) {
3783         return ObjectCache::getInstance( $inputType );
3784 }
3785
3786 /**
3787  * Get the main cache object
3788  *
3789  * @return BagOStuff
3790  */
3791 function wfGetMainCache() {
3792         global $wgMainCacheType;
3793         return ObjectCache::getInstance( $wgMainCacheType );
3794 }
3795
3796 /**
3797  * Get the cache object used by the message cache
3798  *
3799  * @return BagOStuff
3800  */
3801 function wfGetMessageCacheStorage() {
3802         global $wgMessageCacheType;
3803         return ObjectCache::getInstance( $wgMessageCacheType );
3804 }
3805
3806 /**
3807  * Get the cache object used by the parser cache
3808  *
3809  * @return BagOStuff
3810  */
3811 function wfGetParserCacheStorage() {
3812         global $wgParserCacheType;
3813         return ObjectCache::getInstance( $wgParserCacheType );
3814 }
3815
3816 /**
3817  * Get the cache object used by the language converter
3818  *
3819  * @return BagOStuff
3820  */
3821 function wfGetLangConverterCacheStorage() {
3822         global $wgLanguageConverterCacheType;
3823         return ObjectCache::getInstance( $wgLanguageConverterCacheType );
3824 }
3825
3826 /**
3827  * Call hook functions defined in $wgHooks
3828  *
3829  * @param string $event event name
3830  * @param array $args parameters passed to hook functions
3831  * @return Boolean True if no handler aborted the hook
3832  */
3833 function wfRunHooks( $event, array $args = array() ) {
3834         return Hooks::run( $event, $args );
3835 }
3836
3837 /**
3838  * Wrapper around php's unpack.
3839  *
3840  * @param string $format The format string (See php's docs)
3841  * @param $data: A binary string of binary data
3842  * @param $length integer or false: The minimum length of $data. This is to
3843  *      prevent reading beyond the end of $data. false to disable the check.
3844  *
3845  * Also be careful when using this function to read unsigned 32 bit integer
3846  * because php might make it negative.
3847  *
3848  * @throws MWException if $data not long enough, or if unpack fails
3849  * @return array Associative array of the extracted data
3850  */
3851 function wfUnpack( $format, $data, $length = false ) {
3852         if ( $length !== false ) {
3853                 $realLen = strlen( $data );
3854                 if ( $realLen < $length ) {
3855                         throw new MWException( "Tried to use wfUnpack on a "
3856                                 . "string of length $realLen, but needed one "
3857                                 . "of at least length $length."
3858                         );
3859                 }
3860         }
3861
3862         wfSuppressWarnings();
3863         $result = unpack( $format, $data );
3864         wfRestoreWarnings();
3865
3866         if ( $result === false ) {
3867                 // If it cannot extract the packed data.
3868                 throw new MWException( "unpack could not unpack binary data" );
3869         }
3870         return $result;
3871 }
3872
3873 /**
3874  * Determine if an image exists on the 'bad image list'.
3875  *
3876  * The format of MediaWiki:Bad_image_list is as follows:
3877  *    * Only list items (lines starting with "*") are considered
3878  *    * The first link on a line must be a link to a bad image
3879  *    * Any subsequent links on the same line are considered to be exceptions,
3880  *      i.e. articles where the image may occur inline.
3881  *
3882  * @param string $name the image name to check
3883  * @param $contextTitle Title|bool the page on which the image occurs, if known
3884  * @param string $blacklist wikitext of a file blacklist
3885  * @return bool
3886  */
3887 function wfIsBadImage( $name, $contextTitle = false, $blacklist = null ) {
3888         static $badImageCache = null; // based on bad_image_list msg
3889         wfProfileIn( __METHOD__ );
3890
3891         # Handle redirects
3892         $redirectTitle = RepoGroup::singleton()->checkRedirect( Title::makeTitle( NS_FILE, $name ) );
3893         if ( $redirectTitle ) {
3894                 $name = $redirectTitle->getDBkey();
3895         }
3896
3897         # Run the extension hook
3898         $bad = false;
3899         if ( !wfRunHooks( 'BadImage', array( $name, &$bad ) ) ) {
3900                 wfProfileOut( __METHOD__ );
3901                 return $bad;
3902         }
3903
3904         $cacheable = ( $blacklist === null );
3905         if ( $cacheable && $badImageCache !== null ) {
3906                 $badImages = $badImageCache;
3907         } else { // cache miss
3908                 if ( $blacklist === null ) {
3909                         $blacklist = wfMessage( 'bad_image_list' )->inContentLanguage()->plain(); // site list
3910                 }
3911                 # Build the list now
3912                 $badImages = array();
3913                 $lines = explode( "\n", $blacklist );
3914                 foreach ( $lines as $line ) {
3915                         # List items only
3916                         if ( substr( $line, 0, 1 ) !== '*' ) {
3917                                 continue;
3918                         }
3919
3920                         # Find all links
3921                         $m = array();
3922                         if ( !preg_match_all( '/\[\[:?(.*?)\]\]/', $line, $m ) ) {
3923                                 continue;
3924                         }
3925
3926                         $exceptions = array();
3927                         $imageDBkey = false;
3928                         foreach ( $m[1] as $i => $titleText ) {
3929                                 $title = Title::newFromText( $titleText );
3930                                 if ( !is_null( $title ) ) {
3931                                         if ( $i == 0 ) {
3932                                                 $imageDBkey = $title->getDBkey();
3933                                         } else {
3934                                                 $exceptions[$title->getPrefixedDBkey()] = true;
3935                                         }
3936                                 }
3937                         }
3938
3939                         if ( $imageDBkey !== false ) {
3940                                 $badImages[$imageDBkey] = $exceptions;
3941                         }
3942                 }
3943                 if ( $cacheable ) {
3944                         $badImageCache = $badImages;
3945                 }
3946         }
3947
3948         $contextKey = $contextTitle ? $contextTitle->getPrefixedDBkey() : false;
3949         $bad = isset( $badImages[$name] ) && !isset( $badImages[$name][$contextKey] );
3950         wfProfileOut( __METHOD__ );
3951         return $bad;
3952 }