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
  97
  98 // Support for Wietse Venema's taint feature
  99 if ( !function_exists( 'istainted' ) ) {
 100         /**
 101          * @codeCoverageIgnore
 102          * @return int
 103          */
 104         function istainted( $var ) {
 105                 return 0;
 106         }
 107         /** @codeCoverageIgnore */
 108         function taint( $var, $level = 0 ) {}
 109         /** @codeCoverageIgnore */
 110         function untaint( $var, $level = 0 ) {}
 111         define( 'TC_HTML', 1 );
 112         define( 'TC_SHELL', 1 );
 113         define( 'TC_MYSQL', 1 );
 114         define( 'TC_PCRE', 1 );
 115         define( 'TC_SELF', 1 );
 116 }
 117 /// @endcond
 118
 119 /**
 120  * Like array_diff( $a, $b ) except that it works with two-dimensional arrays.
 121  * @param $a array
 122  * @param $b array
 123  * @return array
 124  */
 125 function wfArrayDiff2( $a, $b ) {
 126         return array_udiff( $a, $b, 'wfArrayDiff2_cmp' );
 127 }
 128
 129 /**
 130  * @param $a
 131  * @param $b
 132  * @return int
 133  */
 134 function wfArrayDiff2_cmp( $a, $b ) {
 135         if ( !is_array( $a ) ) {
 136                 return strcmp( $a, $b );
 137         } elseif ( count( $a ) !== count( $b ) ) {
 138                 return count( $a ) < count( $b ) ? -1 : 1;
 139         } else {
 140                 reset( $a );
 141                 reset( $b );
 142                 while( ( list( , $valueA ) = each( $a ) ) && ( list( , $valueB ) = each( $b ) ) ) {
 143                         $cmp = strcmp( $valueA, $valueB );
 144                         if ( $cmp !== 0 ) {
 145                                 return $cmp;
 146                         }
 147                 }
 148                 return 0;
 149         }
 150 }
 151
 152 /**
 153  * Array lookup
 154  * Returns an array where the values in the first array are replaced by the
 155  * values in the second array with the corresponding keys
 156  *
 157  * @param $a Array
 158  * @param $b Array
 159  * @return array
 160  */
 161 function wfArrayLookup( $a, $b ) {
 162         return array_flip( array_intersect( array_flip( $a ), array_keys( $b ) ) );
 163 }
 164
 165 /**
 166  * Appends to second array if $value differs from that in $default
 167  *
 168  * @param $key String|Int
 169  * @param $value Mixed
 170  * @param $default Mixed
 171  * @param $changed Array to alter
 172  * @throws MWException
 173  */
 174 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
 175         if ( is_null( $changed ) ) {
 176                 throw new MWException( 'GlobalFunctions::wfAppendToArrayIfNotDefault got null' );
 177         }
 178         if ( $default[$key] !== $value ) {
 179                 $changed[$key] = $value;
 180         }
 181 }
 182
 183 /**
 184  * Backwards array plus for people who haven't bothered to read the PHP manual
 185  * XXX: will not darn your socks for you.
 186  *
 187  * @param $array1 Array
 188  * @param [$array2, [...]] Arrays
 189  * @return Array
 190  */
 191 function wfArrayMerge( $array1/* ... */ ) {
 192         $args = func_get_args();
 193         $args = array_reverse( $args, true );
 194         $out = array();
 195         foreach ( $args as $arg ) {
 196                 $out += $arg;
 197         }
 198         return $out;
 199 }
 200
 201 /**
 202  * Merge arrays in the style of getUserPermissionsErrors, with duplicate removal
 203  * e.g.
 204  *      wfMergeErrorArrays(
 205  *              array( array( 'x' ) ),
 206  *              array( array( 'x', '2' ) ),
 207  *              array( array( 'x' ) ),
 208  *              array( array( 'y' ) )
 209  *      );
 210  * returns:
 211  *              array(
 212  *              array( 'x', '2' ),
 213  *              array( 'x' ),
 214  *              array( 'y' )
 215  *      )
 216  * @param varargs
 217  * @return Array
 218  */
 219 function wfMergeErrorArrays( /*...*/ ) {
 220         $args = func_get_args();
 221         $out = array();
 222         foreach ( $args as $errors ) {
 223                 foreach ( $errors as $params ) {
 224                         # @todo FIXME: Sometimes get nested arrays for $params,
 225                         # which leads to E_NOTICEs
 226                         $spec = implode( "\t", $params );
 227                         $out[$spec] = $params;
 228                 }
 229         }
 230         return array_values( $out );
 231 }
 232
 233 /**
 234  * Insert array into another array after the specified *KEY*
 235  *
 236  * @param $array Array: The array.
 237  * @param $insert Array: The array to insert.
 238  * @param $after Mixed: The key to insert after
 239  * @return Array
 240  */
 241 function wfArrayInsertAfter( array $array, array $insert, $after ) {
 242         // Find the offset of the element to insert after.
 243         $keys = array_keys( $array );
 244         $offsetByKey = array_flip( $keys );
 245
 246         $offset = $offsetByKey[$after];
 247
 248         // Insert at the specified offset
 249         $before = array_slice( $array, 0, $offset + 1, true );
 250         $after = array_slice( $array, $offset + 1, count( $array ) - $offset, true );
 251
 252         $output = $before + $insert + $after;
 253
 254         return $output;
 255 }
 256
 257 /**
 258  * Recursively converts the parameter (an object) to an array with the same data
 259  *
 260  * @param $objOrArray Object|Array
 261  * @param $recursive Bool
 262  * @return Array
 263  */
 264 function wfObjectToArray( $objOrArray, $recursive = true ) {
 265         $array = array();
 266         if( is_object( $objOrArray ) ) {
 267                 $objOrArray = get_object_vars( $objOrArray );
 268         }
 269         foreach ( $objOrArray as $key => $value ) {
 270                 if ( $recursive && ( is_object( $value ) || is_array( $value ) ) ) {
 271                         $value = wfObjectToArray( $value );
 272                 }
 273
 274                 $array[$key] = $value;
 275         }
 276
 277         return $array;
 278 }
 279
 280 /**
 281  * Wrapper around array_map() which also taints variables
 282  *
 283  * @param  $function Callback
 284  * @param  $input Array
 285  * @return Array
 286  */
 287 function wfArrayMap( $function, $input ) {
 288         $ret = array_map( $function, $input );
 289         foreach ( $ret as $key => $value ) {
 290                 $taint = istainted( $input[$key] );
 291                 if ( $taint ) {
 292                         taint( $ret[$key], $taint );
 293                 }
 294         }
 295         return $ret;
 296 }
 297
 298 /**
 299  * Get a random decimal value between 0 and 1, in a way
 300  * not likely to give duplicate values for any realistic
 301  * number of articles.
 302  *
 303  * @return string
 304  */
 305 function wfRandom() {
 306         # The maximum random value is "only" 2^31-1, so get two random
 307         # values to reduce the chance of dupes
 308         $max = mt_getrandmax() + 1;
 309         $rand = number_format( ( mt_rand() * $max + mt_rand() )
 310                 / $max / $max, 12, '.', '' );
 311         return $rand;
 312 }
 313
 314 /**
 315  * Get a random string containing a number of pesudo-random hex
 316  * characters.
 317  * @note This is not secure, if you are trying to generate some sort
 318  *       of token please use MWCryptRand instead.
 319  *
 320  * @param $length int The length of the string to generate
 321  * @return String
 322  * @since 1.20
 323  */
 324 function wfRandomString( $length = 32 ) {
 325         $str = '';
 326         while ( strlen( $str ) < $length ) {
 327                 $str .= dechex( mt_rand() );
 328         }
 329         return substr( $str, 0, $length );
 330 }
 331
 332 /**
 333  * We want some things to be included as literal characters in our title URLs
 334  * for prettiness, which urlencode encodes by default.  According to RFC 1738,
 335  * all of the following should be safe:
 336  *
 337  * ;:@&=$-_.+!*'(),
 338  *
 339  * But + is not safe because it's used to indicate a space; &= are only safe in
 340  * paths and not in queries (and we don't distinguish here); ' seems kind of
 341  * scary; and urlencode() doesn't touch -_. to begin with.  Plus, although /
 342  * is reserved, we don't care.  So the list we unescape is:
 343  *
 344  * ;:@$!*(),/
 345  *
 346  * However, IIS7 redirects fail when the url contains a colon (Bug 22709),
 347  * so no fancy : for IIS7.
 348  *
 349  * %2F in the page titles seems to fatally break for some reason.
 350  *
 351  * @param $s String:
 352  * @return string
 353 */
 354 function wfUrlencode( $s ) {
 355         static $needle;
 356         if ( is_null( $s ) ) {
 357                 $needle = null;
 358                 return '';
 359         }
 360
 361         if ( is_null( $needle ) ) {
 362                 $needle = array( '%3B', '%40', '%24', '%21', '%2A', '%28', '%29', '%2C', '%2F' );
 363                 if ( !isset( $_SERVER['SERVER_SOFTWARE'] ) || ( strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/7' ) === false ) ) {
 364                         $needle[] = '%3A';
 365                 }
 366         }
 367
 368         $s = urlencode( $s );
 369         $s = str_ireplace(
 370                 $needle,
 371                 array( ';', '@', '$', '!', '*', '(', ')', ',', '/', ':' ),
 372                 $s
 373         );
 374
 375         return $s;
 376 }
 377
 378 /**
 379  * This function takes two arrays as input, and returns a CGI-style string, e.g.
 380  * "days=7&limit=100". Options in the first array override options in the second.
 381  * Options set to null or false will not be output.
 382  *
 383  * @param $array1 Array ( String|Array )
 384  * @param $array2 Array ( String|Array )
 385  * @param $prefix String
 386  * @return String
 387  */
 388 function wfArrayToCgi( $array1, $array2 = null, $prefix = '' ) {
 389         if ( !is_null( $array2 ) ) {
 390                 $array1 = $array1 + $array2;
 391         }
 392
 393         $cgi = '';
 394         foreach ( $array1 as $key => $value ) {
 395                 if ( !is_null( $value ) && $value !== false ) {
 396                         if ( $cgi != '' ) {
 397                                 $cgi .= '&';
 398                         }
 399                         if ( $prefix !== '' ) {
 400                                 $key = $prefix . "[$key]";
 401                         }
 402                         if ( is_array( $value ) ) {
 403                                 $firstTime = true;
 404                                 foreach ( $value as $k => $v ) {
 405                                         $cgi .= $firstTime ? '' : '&';
 406                                         if ( is_array( $v ) ) {
 407                                                 $cgi .= wfArrayToCgi( $v, null, $key . "[$k]" );
 408                                         } else {
 409                                                 $cgi .= urlencode( $key . "[$k]" ) . '=' . urlencode( $v );
 410                                         }
 411                                         $firstTime = false;
 412                                 }
 413                         } else {
 414                                 if ( is_object( $value ) ) {
 415                                         $value = $value->__toString();
 416                                 }
 417                                 $cgi .= urlencode( $key ) . '=' . urlencode( $value );
 418                         }
 419                 }
 420         }
 421         return $cgi;
 422 }
 423
 424 /**
 425  * This is the logical opposite of wfArrayToCgi(): it accepts a query string as
 426  * its argument and returns the same string in array form.  This allows compa-
 427  * tibility with legacy functions that accept raw query strings instead of nice
 428  * arrays.  Of course, keys and values are urldecode()d.
 429  *
 430  * @param $query String: query string
 431  * @return array Array version of input
 432  */
 433 function wfCgiToArray( $query ) {
 434         if ( isset( $query[0] ) && $query[0] == '?' ) {
 435                 $query = substr( $query, 1 );
 436         }
 437         $bits = explode( '&', $query );
 438         $ret = array();
 439         foreach ( $bits as $bit ) {
 440                 if ( $bit === '' ) {
 441                         continue;
 442                 }
 443                 if ( strpos( $bit, '=' ) === false ) {
 444                         // Pieces like &qwerty become 'qwerty' => '' (at least this is what php does)
 445                         $key = $bit;
 446                         $value = '';
 447                 } else {
 448                         list( $key, $value ) = explode( '=', $bit );
 449                 }
 450                 $key = urldecode( $key );
 451                 $value = urldecode( $value );
 452                 if ( strpos( $key, '[' ) !== false ) {
 453                         $keys = array_reverse( explode( '[', $key ) );
 454                         $key = array_pop( $keys );
 455                         $temp = $value;
 456                         foreach ( $keys as $k ) {
 457                                 $k = substr( $k, 0, -1 );
 458                                 $temp = array( $k => $temp );
 459                         }
 460                         if ( isset( $ret[$key] ) ) {
 461                                 $ret[$key] = array_merge( $ret[$key], $temp );
 462                         } else {
 463                                 $ret[$key] = $temp;
 464                         }
 465                 } else {
 466                         $ret[$key] = $value;
 467                 }
 468         }
 469         return $ret;
 470 }
 471
 472 /**
 473  * Append a query string to an existing URL, which may or may not already
 474  * have query string parameters already. If so, they will be combined.
 475  *
 476  * @param $url String
 477  * @param $query Mixed: string or associative array
 478  * @return string
 479  */
 480 function wfAppendQuery( $url, $query ) {
 481         if ( is_array( $query ) ) {
 482                 $query = wfArrayToCgi( $query );
 483         }
 484         if( $query != '' ) {
 485                 if( false === strpos( $url, '?' ) ) {
 486                         $url .= '?';
 487                 } else {
 488                         $url .= '&';
 489                 }
 490                 $url .= $query;
 491         }
 492         return $url;
 493 }
 494
 495 /**
 496  * Expand a potentially local URL to a fully-qualified URL.  Assumes $wgServer
 497  * is correct.
 498  *
 499  * The meaning of the PROTO_* constants is as follows:
 500  * PROTO_HTTP: Output a URL starting with http://
 501  * PROTO_HTTPS: Output a URL starting with https://
 502  * PROTO_RELATIVE: Output a URL starting with // (protocol-relative URL)
 503  * PROTO_CURRENT: Output a URL starting with either http:// or https:// , depending on which protocol was used for the current incoming request
 504  * PROTO_CANONICAL: For URLs without a domain, like /w/index.php , use $wgCanonicalServer. For protocol-relative URLs, use the protocol of $wgCanonicalServer
 505  * PROTO_INTERNAL: Like PROTO_CANONICAL, but uses $wgInternalServer instead of $wgCanonicalServer
 506  *
 507  * @todo this won't work with current-path-relative URLs
 508  * like "subdir/foo.html", etc.
 509  *
 510  * @param $url String: either fully-qualified or a local path + query
 511  * @param $defaultProto Mixed: one of the PROTO_* constants. Determines the
 512  *                             protocol to use if $url or $wgServer is
 513  *                             protocol-relative
 514  * @return string Fully-qualified URL, current-path-relative URL or false if
 515  *                no valid URL can be constructed
 516  */
 517 function wfExpandUrl( $url, $defaultProto = PROTO_CURRENT ) {
 518         global $wgServer, $wgCanonicalServer, $wgInternalServer;
 519         $serverUrl = $wgServer;
 520         if ( $defaultProto === PROTO_CANONICAL ) {
 521                 $serverUrl = $wgCanonicalServer;
 522         }
 523         // Make $wgInternalServer fall back to $wgServer if not set
 524         if ( $defaultProto === PROTO_INTERNAL && $wgInternalServer !== false ) {
 525                 $serverUrl = $wgInternalServer;
 526         }
 527         if ( $defaultProto === PROTO_CURRENT ) {
 528                 $defaultProto = WebRequest::detectProtocol() . '://';
 529         }
 530
 531         // Analyze $serverUrl to obtain its protocol
 532         $bits = wfParseUrl( $serverUrl );
 533         $serverHasProto = $bits && $bits['scheme'] != '';
 534
 535         if ( $defaultProto === PROTO_CANONICAL || $defaultProto === PROTO_INTERNAL ) {
 536                 if ( $serverHasProto ) {
 537                         $defaultProto = $bits['scheme'] . '://';
 538                 } else {
 539                         // $wgCanonicalServer or $wgInternalServer doesn't have a protocol. This really isn't supposed to happen
 540                         // Fall back to HTTP in this ridiculous case
 541                         $defaultProto = PROTO_HTTP;
 542                 }
 543         }
 544
 545         $defaultProtoWithoutSlashes = substr( $defaultProto, 0, -2 );
 546
 547         if ( substr( $url, 0, 2 ) == '//' ) {
 548                 $url = $defaultProtoWithoutSlashes . $url;
 549         } elseif ( substr( $url, 0, 1 ) == '/' ) {
 550                 // If $serverUrl is protocol-relative, prepend $defaultProtoWithoutSlashes, otherwise leave it alone
 551                 $url = ( $serverHasProto ? '' : $defaultProtoWithoutSlashes ) . $serverUrl . $url;
 552         }
 553
 554         $bits = wfParseUrl( $url );
 555         if ( $bits && isset( $bits['path'] ) ) {
 556                 $bits['path'] = wfRemoveDotSegments( $bits['path'] );
 557                 return wfAssembleUrl( $bits );
 558         } elseif ( $bits ) {
 559                 # No path to expand
 560                 return $url;
 561         } elseif ( substr( $url, 0, 1 ) != '/' ) {
 562                 # URL is a relative path
 563                 return wfRemoveDotSegments( $url );
 564         }
 565
 566         # Expanded URL is not valid.
 567         return false;
 568 }
 569
 570 /**
 571  * This function will reassemble a URL parsed with wfParseURL.  This is useful
 572  * if you need to edit part of a URL and put it back together.
 573  *
 574  * This is the basic structure used (brackets contain keys for $urlParts):
 575  * [scheme][delimiter][user]:[pass]@[host]:[port][path]?[query]#[fragment]
 576  *
 577  * @todo Need to integrate this into wfExpandUrl (bug 32168)
 578  *
 579  * @since 1.19
 580  * @param $urlParts Array URL parts, as output from wfParseUrl
 581  * @return string URL assembled from its component parts
 582  */
 583 function wfAssembleUrl( $urlParts ) {
 584         $result = '';
 585
 586         if ( isset( $urlParts['delimiter'] ) ) {
 587                 if ( isset( $urlParts['scheme'] ) ) {
 588                         $result .= $urlParts['scheme'];
 589                 }
 590
 591                 $result .= $urlParts['delimiter'];
 592         }
 593
 594         if ( isset( $urlParts['host'] ) ) {
 595                 if ( isset( $urlParts['user'] ) ) {
 596                         $result .= $urlParts['user'];
 597                         if ( isset( $urlParts['pass'] ) ) {
 598                                 $result .= ':' . $urlParts['pass'];
 599                         }
 600                         $result .= '@';
 601                 }
 602
 603                 $result .= $urlParts['host'];
 604
 605                 if ( isset( $urlParts['port'] ) ) {
 606                         $result .= ':' . $urlParts['port'];
 607                 }
 608         }
 609
 610         if ( isset( $urlParts['path'] ) ) {
 611                 $result .= $urlParts['path'];
 612         }
 613
 614         if ( isset( $urlParts['query'] ) ) {
 615                 $result .= '?' . $urlParts['query'];
 616         }
 617
 618         if ( isset( $urlParts['fragment'] ) ) {
 619                 $result .= '#' . $urlParts['fragment'];
 620         }
 621
 622         return $result;
 623 }
 624
 625 /**
 626  * Remove all dot-segments in the provided URL path.  For example,
 627  * '/a/./b/../c/' becomes '/a/c/'.  For details on the algorithm, please see
 628  * RFC3986 section 5.2.4.
 629  *
 630  * @todo Need to integrate this into wfExpandUrl (bug 32168)
 631  *
 632  * @param $urlPath String URL path, potentially containing dot-segments
 633  * @return string URL path with all dot-segments removed
 634  */
 635 function wfRemoveDotSegments( $urlPath ) {
 636         $output = '';
 637         $inputOffset = 0;
 638         $inputLength = strlen( $urlPath );
 639
 640         while ( $inputOffset < $inputLength ) {
 641                 $prefixLengthOne = substr( $urlPath, $inputOffset, 1 );
 642                 $prefixLengthTwo = substr( $urlPath, $inputOffset, 2 );
 643                 $prefixLengthThree = substr( $urlPath, $inputOffset, 3 );
 644                 $prefixLengthFour = substr( $urlPath, $inputOffset, 4 );
 645                 $trimOutput = false;
 646
 647                 if ( $prefixLengthTwo == './' ) {
 648                         # Step A, remove leading "./"
 649                         $inputOffset += 2;
 650                 } elseif ( $prefixLengthThree == '../' ) {
 651                         # Step A, remove leading "../"
 652                         $inputOffset += 3;
 653                 } elseif ( ( $prefixLengthTwo == '/.' ) && ( $inputOffset + 2 == $inputLength ) ) {
 654                         # Step B, replace leading "/.$" with "/"
 655                         $inputOffset += 1;
 656                         $urlPath[$inputOffset] = '/';
 657                 } elseif ( $prefixLengthThree == '/./' ) {
 658                         # Step B, replace leading "/./" with "/"
 659                         $inputOffset += 2;
 660                 } elseif ( $prefixLengthThree == '/..' && ( $inputOffset + 3 == $inputLength ) ) {
 661                         # Step C, replace leading "/..$" with "/" and
 662                         # remove last path component in output
 663                         $inputOffset += 2;
 664                         $urlPath[$inputOffset] = '/';
 665                         $trimOutput = true;
 666                 } elseif ( $prefixLengthFour == '/../' ) {
 667                         # Step C, replace leading "/../" with "/" and
 668                         # remove last path component in output
 669                         $inputOffset += 3;
 670                         $trimOutput = true;
 671                 } elseif ( ( $prefixLengthOne == '.' ) && ( $inputOffset + 1 == $inputLength ) ) {
 672                         # Step D, remove "^.$"
 673                         $inputOffset += 1;
 674                 } elseif ( ( $prefixLengthTwo == '..' ) && ( $inputOffset + 2 == $inputLength ) ) {
 675                         # Step D, remove "^..$"
 676                         $inputOffset += 2;
 677                 } else {
 678                         # Step E, move leading path segment to output
 679                         if ( $prefixLengthOne == '/' ) {
 680                                 $slashPos = strpos( $urlPath, '/', $inputOffset + 1 );
 681                         } else {
 682                                 $slashPos = strpos( $urlPath, '/', $inputOffset );
 683                         }
 684                         if ( $slashPos === false ) {
 685                                 $output .= substr( $urlPath, $inputOffset );
 686                                 $inputOffset = $inputLength;
 687                         } else {
 688                                 $output .= substr( $urlPath, $inputOffset, $slashPos - $inputOffset );
 689                                 $inputOffset += $slashPos - $inputOffset;
 690                         }
 691                 }
 692
 693                 if ( $trimOutput ) {
 694                         $slashPos = strrpos( $output, '/' );
 695                         if ( $slashPos === false ) {
 696                                 $output = '';
 697                         } else {
 698                                 $output = substr( $output, 0, $slashPos );
 699                         }
 700                 }
 701         }
 702
 703         return $output;
 704 }
 705
 706 /**
 707  * Returns a regular expression of url protocols
 708  *
 709  * @param $includeProtocolRelative bool If false, remove '//' from the returned protocol list.
 710  *        DO NOT USE this directly, use wfUrlProtocolsWithoutProtRel() instead
 711  * @return String
 712  */
 713 function wfUrlProtocols( $includeProtocolRelative = true ) {
 714         global $wgUrlProtocols;
 715
 716         // Cache return values separately based on $includeProtocolRelative
 717         static $withProtRel = null, $withoutProtRel = null;
 718         $cachedValue = $includeProtocolRelative ? $withProtRel : $withoutProtRel;
 719         if ( !is_null( $cachedValue ) ) {
 720                 return $cachedValue;
 721         }
 722
 723         // Support old-style $wgUrlProtocols strings, for backwards compatibility
 724         // with LocalSettings files from 1.5
 725         if ( is_array( $wgUrlProtocols ) ) {
 726                 $protocols = array();
 727                 foreach ( $wgUrlProtocols as $protocol ) {
 728                         // Filter out '//' if !$includeProtocolRelative
 729                         if ( $includeProtocolRelative || $protocol !== '//' ) {
 730                                 $protocols[] = preg_quote( $protocol, '/' );
 731                         }
 732                 }
 733
 734                 $retval = implode( '|', $protocols );
 735         } else {
 736                 // Ignore $includeProtocolRelative in this case
 737                 // This case exists for pre-1.6 compatibility, and we can safely assume
 738                 // that '//' won't appear in a pre-1.6 config because protocol-relative
 739                 // URLs weren't supported until 1.18
 740                 $retval = $wgUrlProtocols;
 741         }
 742
 743         // Cache return value
 744         if ( $includeProtocolRelative ) {
 745                 $withProtRel = $retval;
 746         } else {
 747                 $withoutProtRel = $retval;
 748         }
 749         return $retval;
 750 }
 751
 752 /**
 753  * Like wfUrlProtocols(), but excludes '//' from the protocol list. Use this if
 754  * you need a regex that matches all URL protocols but does not match protocol-
 755  * relative URLs
 756  * @return String
 757  */
 758 function wfUrlProtocolsWithoutProtRel() {
 759         return wfUrlProtocols( false );
 760 }
 761
 762 /**
 763  * parse_url() work-alike, but non-broken.  Differences:
 764  *
 765  * 1) Does not raise warnings on bad URLs (just returns false)
 766  * 2) Handles protocols that don't use :// (e.g., mailto: and news: , as well as protocol-relative URLs) correctly
 767  * 3) Adds a "delimiter" element to the array, either '://', ':' or '//' (see (2))
 768  *
 769  * @param $url String: a URL to parse
 770  * @return Array: bits of the URL in an associative array, per PHP docs
 771  */
 772 function wfParseUrl( $url ) {
 773         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
 774
 775         // Protocol-relative URLs are handled really badly by parse_url(). It's so bad that the easiest
 776         // way to handle them is to just prepend 'http:' and strip the protocol out later
 777         $wasRelative = substr( $url, 0, 2 ) == '//';
 778         if ( $wasRelative ) {
 779                 $url = "http:$url";
 780         }
 781         wfSuppressWarnings();
 782         $bits = parse_url( $url );
 783         wfRestoreWarnings();
 784         // parse_url() returns an array without scheme for some invalid URLs, e.g.
 785         // parse_url("%0Ahttp://example.com") == array( 'host' => '%0Ahttp', 'path' => 'example.com' )
 786         if ( !$bits || !isset( $bits['scheme'] ) ) {
 787                 return false;
 788         }
 789
 790         // parse_url() incorrectly handles schemes case-sensitively. Convert it to lowercase.
 791         $bits['scheme'] = strtolower( $bits['scheme'] );
 792
 793         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
 794         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
 795                 $bits['delimiter'] = '://';
 796         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
 797                 $bits['delimiter'] = ':';
 798                 // parse_url detects for news: and mailto: the host part of an url as path
 799                 // We have to correct this wrong detection
 800                 if ( isset( $bits['path'] ) ) {
 801                         $bits['host'] = $bits['path'];
 802                         $bits['path'] = '';
 803                 }
 804         } else {
 805                 return false;
 806         }
 807
 808         /* Provide an empty host for eg. file:/// urls (see bug 28627) */
 809         if ( !isset( $bits['host'] ) ) {
 810                 $bits['host'] = '';
 811
 812                 /* parse_url loses the third / for file:///c:/ urls (but not on variants) */
 813                 if ( substr( $bits['path'], 0, 1 ) !== '/' ) {
 814                         $bits['path'] = '/' . $bits['path'];
 815                 }
 816         }
 817
 818         // If the URL was protocol-relative, fix scheme and delimiter
 819         if ( $wasRelative ) {
 820                 $bits['scheme'] = '';
 821                 $bits['delimiter'] = '//';
 822         }
 823         return $bits;
 824 }
 825
 826 /**
 827  * Take a URL, make sure it's expanded to fully qualified, and replace any
 828  * encoded non-ASCII Unicode characters with their UTF-8 original forms
 829  * for more compact display and legibility for local audiences.
 830  *
 831  * @todo handle punycode domains too
 832  *
 833  * @param $url string
 834  * @return string
 835  */
 836 function wfExpandIRI( $url ) {
 837         return preg_replace_callback( '/((?:%[89A-F][0-9A-F])+)/i', 'wfExpandIRI_callback', wfExpandUrl( $url ) );
 838 }
 839
 840 /**
 841  * Private callback for wfExpandIRI
 842  * @param array $matches
 843  * @return string
 844  */
 845 function wfExpandIRI_callback( $matches ) {
 846         return urldecode( $matches[1] );
 847 }
 848
 849
 850
 851 /**
 852  * Make URL indexes, appropriate for the el_index field of externallinks.
 853  *
 854  * @param $url String
 855  * @return array
 856  */
 857 function wfMakeUrlIndexes( $url ) {
 858         $bits = wfParseUrl( $url );
 859
 860         // Reverse the labels in the hostname, convert to lower case
 861         // For emails reverse domainpart only
 862         if ( $bits['scheme'] == 'mailto' ) {
 863                 $mailparts = explode( '@', $bits['host'], 2 );
 864                 if ( count( $mailparts ) === 2 ) {
 865                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
 866                 } else {
 867                         // No domain specified, don't mangle it
 868                         $domainpart = '';
 869                 }
 870                 $reversedHost = $domainpart . '@' . $mailparts[0];
 871         } else {
 872                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
 873         }
 874         // Add an extra dot to the end
 875         // Why? Is it in wrong place in mailto links?
 876         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
 877                 $reversedHost .= '.';
 878         }
 879         // Reconstruct the pseudo-URL
 880         $prot = $bits['scheme'];
 881         $index = $prot . $bits['delimiter'] . $reversedHost;
 882         // Leave out user and password. Add the port, path, query and fragment
 883         if ( isset( $bits['port'] ) ) {
 884                 $index .= ':' . $bits['port'];
 885         }
 886         if ( isset( $bits['path'] ) ) {
 887                 $index .= $bits['path'];
 888         } else {
 889                 $index .= '/';
 890         }
 891         if ( isset( $bits['query'] ) ) {
 892                 $index .= '?' . $bits['query'];
 893         }
 894         if ( isset( $bits['fragment'] ) ) {
 895                 $index .= '#' . $bits['fragment'];
 896         }
 897
 898         if ( $prot == '' ) {
 899                 return array( "http:$index", "https:$index" );
 900         } else {
 901                 return array( $index );
 902         }
 903 }
 904
 905 /**
 906  * Check whether a given URL has a domain that occurs in a given set of domains
 907  * @param $url string URL
 908  * @param $domains array Array of domains (strings)
 909  * @return bool True if the host part of $url ends in one of the strings in $domains
 910  */
 911 function wfMatchesDomainList( $url, $domains ) {
 912         $bits = wfParseUrl( $url );
 913         if ( is_array( $bits ) && isset( $bits['host'] ) ) {
 914                 foreach ( (array)$domains as $domain ) {
 915                         // FIXME: This gives false positives. http://nds-nl.wikipedia.org will match nl.wikipedia.org
 916                         // We should use something that interprets dots instead
 917                         if ( substr( $bits['host'], -strlen( $domain ) ) === $domain ) {
 918                                 return true;
 919                         }
 920                 }
 921         }
 922         return false;
 923 }
 924
 925 /**
 926  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
 927  * In normal operation this is a NOP.
 928  *
 929  * Controlling globals:
 930  * $wgDebugLogFile - points to the log file
 931  * $wgProfileOnly - if set, normal debug messages will not be recorded.
 932  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
 933  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
 934  *
 935  * @param $text String
 936  * @param $logonly Bool: set true to avoid appearing in HTML when $wgDebugComments is set
 937  */
 938 function wfDebug( $text, $logonly = false ) {
 939         global $wgDebugLogFile, $wgProfileOnly, $wgDebugRawPage, $wgDebugLogPrefix;
 940
 941         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
 942                 return;
 943         }
 944
 945         $timer = wfDebugTimer();
 946         if ( $timer !== '' ) {
 947                 $text = preg_replace( '/[^\n]/', $timer . '\0', $text, 1 );
 948         }
 949
 950         if ( !$logonly ) {
 951                 MWDebug::debugMsg( $text );
 952         }
 953
 954         if ( wfRunHooks( 'Debug', array( $text, null /* no log group */ ) ) ) {
 955                 if ( $wgDebugLogFile != '' && !$wgProfileOnly ) {
 956                         # Strip unprintables; they can switch terminal modes when binary data
 957                         # gets dumped, which is pretty annoying.
 958                         $text = preg_replace( '![\x00-\x08\x0b\x0c\x0e-\x1f]!', ' ', $text );
 959                         $text = $wgDebugLogPrefix . $text;
 960                         wfErrorLog( $text, $wgDebugLogFile );
 961                 }
 962         }
 963 }
 964
 965 /**
 966  * Returns true if debug logging should be suppressed if $wgDebugRawPage = false
 967  * @return bool
 968  */
 969 function wfIsDebugRawPage() {
 970         static $cache;
 971         if ( $cache !== null ) {
 972                 return $cache;
 973         }
 974         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
 975         if ( ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' )
 976                 || (
 977                         isset( $_SERVER['SCRIPT_NAME'] )
 978                         && substr( $_SERVER['SCRIPT_NAME'], -8 ) == 'load.php'
 979                 ) )
 980         {
 981                 $cache = true;
 982         } else {
 983                 $cache = false;
 984         }
 985         return $cache;
 986 }
 987
 988 /**
 989  * Get microsecond timestamps for debug logs
 990  *
 991  * @return string
 992  */
 993 function wfDebugTimer() {
 994         global $wgDebugTimestamps, $wgRequestTime;
 995
 996         if ( !$wgDebugTimestamps ) {
 997                 return '';
 998         }
 999
1000         $prefix = sprintf( "%6.4f", microtime( true ) - $wgRequestTime );
1001         $mem = sprintf( "%5.1fM", ( memory_get_usage( true ) / ( 1024 * 1024 ) ) );
1002         return "$prefix $mem  ";
1003 }
1004
1005 /**
1006  * Send a line giving PHP memory usage.
1007  *
1008  * @param $exact Bool: print exact values instead of kilobytes (default: false)
1009  */
1010 function wfDebugMem( $exact = false ) {
1011         $mem = memory_get_usage();
1012         if( !$exact ) {
1013                 $mem = floor( $mem / 1024 ) . ' kilobytes';
1014         } else {
1015                 $mem .= ' bytes';
1016         }
1017         wfDebug( "Memory usage: $mem\n" );
1018 }
1019
1020 /**
1021  * Send a line to a supplementary debug log file, if configured, or main debug log if not.
1022  * $wgDebugLogGroups[$logGroup] should be set to a filename to send to a separate log.
1023  *
1024  * @param $logGroup String
1025  * @param $text String
1026  * @param $public Bool: whether to log the event in the public log if no private
1027  *                     log file is specified, (default true)
1028  */
1029 function wfDebugLog( $logGroup, $text, $public = true ) {
1030         global $wgDebugLogGroups;
1031         $text = trim( $text ) . "\n";
1032         if( isset( $wgDebugLogGroups[$logGroup] ) ) {
1033                 $time = wfTimestamp( TS_DB );
1034                 $wiki = wfWikiID();
1035                 $host = wfHostname();
1036                 if ( wfRunHooks( 'Debug', array( $text, $logGroup ) ) ) {
1037                         wfErrorLog( "$time $host $wiki: $text", $wgDebugLogGroups[$logGroup] );
1038                 }
1039         } elseif ( $public === true ) {
1040                 wfDebug( "[$logGroup] $text", true );
1041         }
1042 }
1043
1044 /**
1045  * Log for database errors
1046  *
1047  * @param $text String: database error message.
1048  */
1049 function wfLogDBError( $text ) {
1050         global $wgDBerrorLog, $wgDBerrorLogTZ;
1051         static $logDBErrorTimeZoneObject = null;
1052
1053         if ( $wgDBerrorLog ) {
1054                 $host = wfHostname();
1055                 $wiki = wfWikiID();
1056
1057                 if ( $wgDBerrorLogTZ && !$logDBErrorTimeZoneObject ) {
1058                         $logDBErrorTimeZoneObject = new DateTimeZone( $wgDBerrorLogTZ );
1059                 }
1060
1061                 // Workaround for https://bugs.php.net/bug.php?id=52063
1062                 // Can be removed when min PHP > 5.3.2
1063                 if ( $logDBErrorTimeZoneObject === null ) {
1064                         $d = date_create( "now" );
1065                 } else {
1066                         $d = date_create( "now", $logDBErrorTimeZoneObject );
1067                 }
1068
1069                 $date = $d->format( 'D M j G:i:s T Y' );
1070
1071                 $text = "$date\t$host\t$wiki\t$text";
1072                 wfErrorLog( $text, $wgDBerrorLog );
1073         }
1074 }
1075
1076 /**
1077  * Throws a warning that $function is deprecated
1078  *
1079  * @param $function String
1080  * @param $version String|bool: Version of MediaWiki that the function was deprecated in (Added in 1.19).
1081  * @param $component String|bool: Added in 1.19.
1082  * @param $callerOffset integer: How far up the callstack is the original
1083  *    caller. 2 = function that called the function that called
1084  *    wfDeprecated (Added in 1.20)
1085  *
1086  * @return null
1087  */
1088 function wfDeprecated( $function, $version = false, $component = false, $callerOffset = 2 ) {
1089         MWDebug::deprecated( $function, $version, $component, $callerOffset + 1 );
1090 }
1091
1092 /**
1093  * Send a warning either to the debug log or in a PHP error depending on
1094  * $wgDevelopmentWarnings
1095  *
1096  * @param $msg String: message to send
1097  * @param $callerOffset Integer: number of items to go back in the backtrace to
1098  *        find the correct caller (1 = function calling wfWarn, ...)
1099  * @param $level Integer: PHP error level; only used when $wgDevelopmentWarnings
1100  *        is true
1101  */
1102 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
1103         MWDebug::warning( $msg, $callerOffset + 1, $level );
1104 }
1105
1106 /**
1107  * Log to a file without getting "file size exceeded" signals.
1108  *
1109  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
1110  * send lines to the specified port, prefixed by the specified prefix and a space.
1111  *
1112  * @param $text String
1113  * @param $file String filename
1114  * @throws MWException
1115  */
1116 function wfErrorLog( $text, $file ) {
1117         if ( substr( $file, 0, 4 ) == 'udp:' ) {
1118                 # Needs the sockets extension
1119                 if ( preg_match( '!^(tcp|udp):(?://)?\[([0-9a-fA-F:]+)\]:(\d+)(?:/(.*))?$!', $file, $m ) ) {
1120                         // IPv6 bracketed host
1121                         $host = $m[2];
1122                         $port = intval( $m[3] );
1123                         $prefix = isset( $m[4] ) ? $m[4] : false;
1124                         $domain = AF_INET6;
1125                 } elseif ( preg_match( '!^(tcp|udp):(?://)?([a-zA-Z0-9.-]+):(\d+)(?:/(.*))?$!', $file, $m ) ) {
1126                         $host = $m[2];
1127                         if ( !IP::isIPv4( $host ) ) {
1128                                 $host = gethostbyname( $host );
1129                         }
1130                         $port = intval( $m[3] );
1131                         $prefix = isset( $m[4] ) ? $m[4] : false;
1132                         $domain = AF_INET;
1133                 } else {
1134                         throw new MWException( __METHOD__ . ': Invalid UDP specification' );
1135                 }
1136
1137                 // Clean it up for the multiplexer
1138                 if ( strval( $prefix ) !== '' ) {
1139                         $text = preg_replace( '/^/m', $prefix . ' ', $text );
1140
1141                         // Limit to 64KB
1142                         if ( strlen( $text ) > 65506 ) {
1143                                 $text = substr( $text, 0, 65506 );
1144                         }
1145
1146                         if ( substr( $text, -1 ) != "\n" ) {
1147                                 $text .= "\n";
1148                         }
1149                 } elseif ( strlen( $text ) > 65507 ) {
1150                         $text = substr( $text, 0, 65507 );
1151                 }
1152
1153                 $sock = socket_create( $domain, SOCK_DGRAM, SOL_UDP );
1154                 if ( !$sock ) {
1155                         return;
1156                 }
1157
1158                 socket_sendto( $sock, $text, strlen( $text ), 0, $host, $port );
1159                 socket_close( $sock );
1160         } else {
1161                 wfSuppressWarnings();
1162                 $exists = file_exists( $file );
1163                 $size = $exists ? filesize( $file ) : false;
1164                 if ( !$exists || ( $size !== false && $size + strlen( $text ) < 0x7fffffff ) ) {
1165                         file_put_contents( $file, $text, FILE_APPEND );
1166                 }
1167                 wfRestoreWarnings();
1168         }
1169 }
1170
1171 /**
1172  * @todo document
1173  */
1174 function wfLogProfilingData() {
1175         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
1176         global $wgProfileLimit, $wgUser;
1177
1178         $profiler = Profiler::instance();
1179
1180         # Profiling must actually be enabled...
1181         if ( $profiler->isStub() ) {
1182                 return;
1183         }
1184
1185         // Get total page request time and only show pages that longer than
1186         // $wgProfileLimit time (default is 0)
1187         $elapsed = microtime( true ) - $wgRequestTime;
1188         if ( $elapsed <= $wgProfileLimit ) {
1189                 return;
1190         }
1191
1192         $profiler->logData();
1193
1194         // Check whether this should be logged in the debug file.
1195         if ( $wgDebugLogFile == '' || ( !$wgDebugRawPage && wfIsDebugRawPage() ) ) {
1196                 return;
1197         }
1198
1199         $forward = '';
1200         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
1201                 $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
1202         }
1203         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
1204                 $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
1205         }
1206         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
1207                 $forward .= ' from ' . $_SERVER['HTTP_FROM'];
1208         }
1209         if ( $forward ) {
1210                 $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
1211         }
1212         // Don't load $wgUser at this late stage just for statistics purposes
1213         // @todo FIXME: We can detect some anons even if it is not loaded. See User::getId()
1214         if ( $wgUser->isItemLoaded( 'id' ) && $wgUser->isAnon() ) {
1215                 $forward .= ' anon';
1216         }
1217
1218         // Command line script uses a FauxRequest object which does not have
1219         // any knowledge about an URL and throw an exception instead.
1220         try {
1221                 $requestUrl = $wgRequest->getRequestURL();
1222         } catch ( MWException $e ) {
1223                 $requestUrl = 'n/a';
1224         }
1225
1226         $log = sprintf( "%s\t%04.3f\t%s\n",
1227                 gmdate( 'YmdHis' ), $elapsed,
1228                 urldecode( $requestUrl . $forward ) );
1229
1230         wfErrorLog( $log . $profiler->getOutput(), $wgDebugLogFile );
1231 }
1232
1233 /**
1234  * Increment a statistics counter
1235  *
1236  * @param $key String
1237  * @param $count Int
1238  * @return void
1239  */
1240 function wfIncrStats( $key, $count = 1 ) {
1241         global $wgStatsMethod;
1242
1243         $count = intval( $count );
1244         if ( $count == 0 ) {
1245                 return;
1246         }
1247
1248         if( $wgStatsMethod == 'udp' ) {
1249                 global $wgUDPProfilerHost, $wgUDPProfilerPort, $wgAggregateStatsID;
1250                 static $socket;
1251
1252                 $id = $wgAggregateStatsID !== false ? $wgAggregateStatsID : wfWikiID();
1253
1254                 if ( !$socket ) {
1255                         $socket = socket_create( AF_INET, SOCK_DGRAM, SOL_UDP );
1256                         $statline = "stats/{$id} - 1 1 1 1 1 -total\n";
1257                         socket_sendto(
1258                                 $socket,
1259                                 $statline,
1260                                 strlen( $statline ),
1261                                 0,
1262                                 $wgUDPProfilerHost,
1263                                 $wgUDPProfilerPort
1264                         );
1265                 }
1266                 $statline = "stats/{$id} - {$count} 1 1 1 1 {$key}\n";
1267                 wfSuppressWarnings();
1268                 socket_sendto(
1269                         $socket,
1270                         $statline,
1271                         strlen( $statline ),
1272                         0,
1273                         $wgUDPProfilerHost,
1274                         $wgUDPProfilerPort
1275                 );
1276                 wfRestoreWarnings();
1277         } elseif( $wgStatsMethod == 'cache' ) {
1278                 global $wgMemc;
1279                 $key = wfMemcKey( 'stats', $key );
1280                 if ( is_null( $wgMemc->incr( $key, $count ) ) ) {
1281                         $wgMemc->add( $key, $count );
1282                 }
1283         } else {
1284                 // Disabled
1285         }
1286 }
1287
1288 /**
1289  * Check if the wiki read-only lock file is present. This can be used to lock
1290  * off editing functions, but doesn't guarantee that the database will not be
1291  * modified.
1292  *
1293  * @return bool
1294  */
1295 function wfReadOnly() {
1296         global $wgReadOnlyFile, $wgReadOnly;
1297
1298         if ( !is_null( $wgReadOnly ) ) {
1299                 return (bool)$wgReadOnly;
1300         }
1301         if ( $wgReadOnlyFile == '' ) {
1302                 return false;
1303         }
1304         // Set $wgReadOnly for faster access next time
1305         if ( is_file( $wgReadOnlyFile ) ) {
1306                 $wgReadOnly = file_get_contents( $wgReadOnlyFile );
1307         } else {
1308                 $wgReadOnly = false;
1309         }
1310         return (bool)$wgReadOnly;
1311 }
1312
1313 /**
1314  * @return bool
1315  */
1316 function wfReadOnlyReason() {
1317         global $wgReadOnly;
1318         wfReadOnly();
1319         return $wgReadOnly;
1320 }
1321
1322 /**
1323  * Return a Language object from $langcode
1324  *
1325  * @param $langcode Mixed: either:
1326  *                  - a Language object
1327  *                  - code of the language to get the message for, if it is
1328  *                    a valid code create a language for that language, if
1329  *                    it is a string but not a valid code then make a basic
1330  *                    language object
1331  *                  - a boolean: if it's false then use the global object for
1332  *                    the current user's language (as a fallback for the old parameter
1333  *                    functionality), or if it is true then use global object
1334  *                    for the wiki's content language.
1335  * @return Language object
1336  */
1337 function wfGetLangObj( $langcode = false ) {
1338         # Identify which language to get or create a language object for.
1339         # Using is_object here due to Stub objects.
1340         if( is_object( $langcode ) ) {
1341                 # Great, we already have the object (hopefully)!
1342                 return $langcode;
1343         }
1344
1345         global $wgContLang, $wgLanguageCode;
1346         if( $langcode === true || $langcode === $wgLanguageCode ) {
1347                 # $langcode is the language code of the wikis content language object.
1348                 # or it is a boolean and value is true
1349                 return $wgContLang;
1350         }
1351
1352         global $wgLang;
1353         if( $langcode === false || $langcode === $wgLang->getCode() ) {
1354                 # $langcode is the language code of user language object.
1355                 # or it was a boolean and value is false
1356                 return $wgLang;
1357         }
1358
1359         $validCodes = array_keys( Language::fetchLanguageNames() );
1360         if( in_array( $langcode, $validCodes ) ) {
1361                 # $langcode corresponds to a valid language.
1362                 return Language::factory( $langcode );
1363         }
1364
1365         # $langcode is a string, but not a valid language code; use content language.
1366         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
1367         return $wgContLang;
1368 }
1369
1370 /**
1371  * Old function when $wgBetterDirectionality existed
1372  * All usage removed, wfUILang can be removed in near future
1373  *
1374  * @deprecated since 1.18
1375  * @return Language
1376  */
1377 function wfUILang() {
1378         wfDeprecated( __METHOD__, '1.18' );
1379         global $wgLang;
1380         return $wgLang;
1381 }
1382
1383 /**
1384  * This is the new function for getting translated interface messages.
1385  * See the Message class for documentation how to use them.
1386  * The intention is that this function replaces all old wfMsg* functions.
1387  * @param $key \string Message key.
1388  * Varargs: normal message parameters.
1389  * @return Message
1390  * @since 1.17
1391  */
1392 function wfMessage( $key /*...*/) {
1393         $params = func_get_args();
1394         array_shift( $params );
1395         if ( isset( $params[0] ) && is_array( $params[0] ) ) {
1396                 $params = $params[0];
1397         }
1398         return new Message( $key, $params );
1399 }
1400
1401 /**
1402  * This function accepts multiple message keys and returns a message instance
1403  * for the first message which is non-empty. If all messages are empty then an
1404  * instance of the first message key is returned.
1405  * @param varargs: message keys
1406  * @return Message
1407  * @since 1.18
1408  */
1409 function wfMessageFallback( /*...*/ ) {
1410         $args = func_get_args();
1411         return MWFunction::callArray( 'Message::newFallbackSequence', $args );
1412 }
1413
1414 /**
1415  * Get a message from anywhere, for the current user language.
1416  *
1417  * Use wfMsgForContent() instead if the message should NOT
1418  * change depending on the user preferences.
1419  *
1420  * @deprecated since 1.18
1421  *
1422  * @param $key String: lookup key for the message, usually
1423  *    defined in languages/Language.php
1424  *
1425  * Parameters to the message, which can be used to insert variable text into
1426  * it, can be passed to this function in the following formats:
1427  * - One per argument, starting at the second parameter
1428  * - As an array in the second parameter
1429  * These are not shown in the function definition.
1430  *
1431  * @return String
1432  */
1433 function wfMsg( $key ) {
1434         wfDeprecated( __METHOD__, '1.21' );
1435
1436         $args = func_get_args();
1437         array_shift( $args );
1438         return wfMsgReal( $key, $args );
1439 }
1440
1441 /**
1442  * Same as above except doesn't transform the message
1443  *
1444  * @deprecated since 1.18
1445  *
1446  * @param $key String
1447  * @return String
1448  */
1449 function wfMsgNoTrans( $key ) {
1450         wfDeprecated( __METHOD__, '1.21' );
1451
1452         $args = func_get_args();
1453         array_shift( $args );
1454         return wfMsgReal( $key, $args, true, false, false );
1455 }
1456
1457 /**
1458  * Get a message from anywhere, for the current global language
1459  * set with $wgLanguageCode.
1460  *
1461  * Use this if the message should NOT change dependent on the
1462  * language set in the user's preferences. This is the case for
1463  * most text written into logs, as well as link targets (such as
1464  * the name of the copyright policy page). Link titles, on the
1465  * other hand, should be shown in the UI language.
1466  *
1467  * Note that MediaWiki allows users to change the user interface
1468  * language in their preferences, but a single installation
1469  * typically only contains content in one language.
1470  *
1471  * Be wary of this distinction: If you use wfMsg() where you should
1472  * use wfMsgForContent(), a user of the software may have to
1473  * customize potentially hundreds of messages in
1474  * order to, e.g., fix a link in every possible language.
1475  *
1476  * @deprecated since 1.18
1477  *
1478  * @param $key String: lookup key for the message, usually
1479  *     defined in languages/Language.php
1480  * @return String
1481  */
1482 function wfMsgForContent( $key ) {
1483         wfDeprecated( __METHOD__, '1.21' );
1484
1485         global $wgForceUIMsgAsContentMsg;
1486         $args = func_get_args();
1487         array_shift( $args );
1488         $forcontent = true;
1489         if( is_array( $wgForceUIMsgAsContentMsg ) &&
1490                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
1491         {
1492                 $forcontent = false;
1493         }
1494         return wfMsgReal( $key, $args, true, $forcontent );
1495 }
1496
1497 /**
1498  * Same as above except doesn't transform the message
1499  *
1500  * @deprecated since 1.18
1501  *
1502  * @param $key String
1503  * @return String
1504  */
1505 function wfMsgForContentNoTrans( $key ) {
1506         wfDeprecated( __METHOD__, '1.21' );
1507
1508         global $wgForceUIMsgAsContentMsg;
1509         $args = func_get_args();
1510         array_shift( $args );
1511         $forcontent = true;
1512         if( is_array( $wgForceUIMsgAsContentMsg ) &&
1513                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
1514         {
1515                 $forcontent = false;
1516         }
1517         return wfMsgReal( $key, $args, true, $forcontent, false );
1518 }
1519
1520 /**
1521  * Really get a message
1522  *
1523  * @deprecated since 1.18
1524  *
1525  * @param $key String: key to get.
1526  * @param $args
1527  * @param $useDB Boolean
1528  * @param $forContent Mixed: Language code, or false for user lang, true for content lang.
1529  * @param $transform Boolean: Whether or not to transform the message.
1530  * @return String: the requested message.
1531  */
1532 function wfMsgReal( $key, $args, $useDB = true, $forContent = false, $transform = true ) {
1533         wfDeprecated( __METHOD__, '1.21' );
1534
1535         wfProfileIn( __METHOD__ );
1536         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
1537         $message = wfMsgReplaceArgs( $message, $args );
1538         wfProfileOut( __METHOD__ );
1539         return $message;
1540 }
1541
1542 /**
1543  * Fetch a message string value, but don't replace any keys yet.
1544  *
1545  * @deprecated since 1.18
1546  *
1547  * @param $key String
1548  * @param $useDB Bool
1549  * @param $langCode String: Code of the language to get the message for, or
1550  *                  behaves as a content language switch if it is a boolean.
1551  * @param $transform Boolean: whether to parse magic words, etc.
1552  * @return string
1553  */
1554 function wfMsgGetKey( $key, $useDB = true, $langCode = false, $transform = true ) {
1555         wfDeprecated( __METHOD__, '1.21' );
1556
1557         wfRunHooks( 'NormalizeMessageKey', array( &$key, &$useDB, &$langCode, &$transform ) );
1558
1559         $cache = MessageCache::singleton();
1560         $message = $cache->get( $key, $useDB, $langCode );
1561         if( $message === false ) {
1562                 $message = '&lt;' . htmlspecialchars( $key ) . '&gt;';
1563         } elseif ( $transform ) {
1564                 $message = $cache->transform( $message );
1565         }
1566         return $message;
1567 }
1568
1569 /**
1570  * Replace message parameter keys on the given formatted output.
1571  *
1572  * @param $message String
1573  * @param $args Array
1574  * @return string
1575  * @private
1576  */
1577 function wfMsgReplaceArgs( $message, $args ) {
1578         # Fix windows line-endings
1579         # Some messages are split with explode("\n", $msg)
1580         $message = str_replace( "\r", '', $message );
1581
1582         // Replace arguments
1583         if ( count( $args ) ) {
1584                 if ( is_array( $args[0] ) ) {
1585                         $args = array_values( $args[0] );
1586                 }
1587                 $replacementKeys = array();
1588                 foreach( $args as $n => $param ) {
1589                         $replacementKeys['$' . ( $n + 1 )] = $param;
1590                 }
1591                 $message = strtr( $message, $replacementKeys );
1592         }
1593
1594         return $message;
1595 }
1596
1597 /**
1598  * Return an HTML-escaped version of a message.
1599  * Parameter replacements, if any, are done *after* the HTML-escaping,
1600  * so parameters may contain HTML (eg links or form controls). Be sure
1601  * to pre-escape them if you really do want plaintext, or just wrap
1602  * the whole thing in htmlspecialchars().
1603  *
1604  * @deprecated since 1.18
1605  *
1606  * @param $key String
1607  * @param string ... parameters
1608  * @return string
1609  */
1610 function wfMsgHtml( $key ) {
1611         wfDeprecated( __METHOD__, '1.21' );
1612
1613         $args = func_get_args();
1614         array_shift( $args );
1615         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key ) ), $args );
1616 }
1617
1618 /**
1619  * Return an HTML version of message
1620  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
1621  * so parameters may contain HTML (eg links or form controls). Be sure
1622  * to pre-escape them if you really do want plaintext, or just wrap
1623  * the whole thing in htmlspecialchars().
1624  *
1625  * @deprecated since 1.18
1626  *
1627  * @param $key String
1628  * @param string ... parameters
1629  * @return string
1630  */
1631 function wfMsgWikiHtml( $key ) {
1632         wfDeprecated( __METHOD__, '1.21' );
1633
1634         $args = func_get_args();
1635         array_shift( $args );
1636         return wfMsgReplaceArgs(
1637                 MessageCache::singleton()->parse( wfMsgGetKey( $key ), null,
1638                 /* can't be set to false */ true, /* interface */ true )->getText(),
1639                 $args );
1640 }
1641
1642 /**
1643  * Returns message in the requested format
1644  *
1645  * @deprecated since 1.18
1646  *
1647  * @param $key String: key of the message
1648  * @param $options Array: processing rules. Can take the following options:
1649  *   <i>parse</i>: parses wikitext to HTML
1650  *   <i>parseinline</i>: parses wikitext to HTML and removes the surrounding
1651  *       p's added by parser or tidy
1652  *   <i>escape</i>: filters message through htmlspecialchars
1653  *   <i>escapenoentities</i>: same, but allows entity references like &#160; through
1654  *   <i>replaceafter</i>: parameters are substituted after parsing or escaping
1655  *   <i>parsemag</i>: transform the message using magic phrases
1656  *   <i>content</i>: fetch message for content language instead of interface
1657  * Also can accept a single associative argument, of the form 'language' => 'xx':
1658  *   <i>language</i>: Language object or language code to fetch message for
1659  *       (overriden by <i>content</i>).
1660  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
1661  *
1662  * @return String
1663  */
1664 function wfMsgExt( $key, $options ) {
1665         wfDeprecated( __METHOD__, '1.21' );
1666
1667         $args = func_get_args();
1668         array_shift( $args );
1669         array_shift( $args );
1670         $options = (array)$options;
1671
1672         foreach( $options as $arrayKey => $option ) {
1673                 if( !preg_match( '/^[0-9]+|language$/', $arrayKey ) ) {
1674                         # An unknown index, neither numeric nor "language"
1675                         wfWarn( "wfMsgExt called with incorrect parameter key $arrayKey", 1, E_USER_WARNING );
1676                 } elseif( preg_match( '/^[0-9]+$/', $arrayKey ) && !in_array( $option,
1677                 array( 'parse', 'parseinline', 'escape', 'escapenoentities',
1678                 'replaceafter', 'parsemag', 'content' ) ) ) {
1679                         # A numeric index with unknown value
1680                         wfWarn( "wfMsgExt called with incorrect parameter $option", 1, E_USER_WARNING );
1681                 }
1682         }
1683
1684         if( in_array( 'content', $options, true ) ) {
1685                 $forContent = true;
1686                 $langCode = true;
1687                 $langCodeObj = null;
1688         } elseif( array_key_exists( 'language', $options ) ) {
1689                 $forContent = false;
1690                 $langCode = wfGetLangObj( $options['language'] );
1691                 $langCodeObj = $langCode;
1692         } else {
1693                 $forContent = false;
1694                 $langCode = false;
1695                 $langCodeObj = null;
1696         }
1697
1698         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
1699
1700         if( !in_array( 'replaceafter', $options, true ) ) {
1701                 $string = wfMsgReplaceArgs( $string, $args );
1702         }
1703
1704         $messageCache = MessageCache::singleton();
1705         $parseInline = in_array( 'parseinline', $options, true );
1706         if( in_array( 'parse', $options, true ) || $parseInline ) {
1707                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj );
1708                 if ( $string instanceof ParserOutput ) {
1709                         $string = $string->getText();
1710                 }
1711
1712                 if ( $parseInline ) {
1713                         $m = array();
1714                         if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
1715                                 $string = $m[1];
1716                         }
1717                 }
1718         } elseif ( in_array( 'parsemag', $options, true ) ) {
1719                 $string = $messageCache->transform( $string,
1720                                 !$forContent, $langCodeObj );
1721         }
1722
1723         if ( in_array( 'escape', $options, true ) ) {
1724                 $string = htmlspecialchars ( $string );
1725         } elseif ( in_array( 'escapenoentities', $options, true ) ) {
1726                 $string = Sanitizer::escapeHtmlAllowEntities( $string );
1727         }
1728
1729         if( in_array( 'replaceafter', $options, true ) ) {
1730                 $string = wfMsgReplaceArgs( $string, $args );
1731         }
1732
1733         return $string;
1734 }
1735
1736 /**
1737  * Since wfMsg() and co suck, they don't return false if the message key they
1738  * looked up didn't exist but a XHTML string, this function checks for the
1739  * nonexistance of messages by checking the MessageCache::get() result directly.
1740  *
1741  * @deprecated since 1.18. Use Message::isDisabled().
1742  *
1743  * @param $key      String: the message key looked up
1744  * @return Boolean True if the message *doesn't* exist.
1745  */
1746 function wfEmptyMsg( $key ) {
1747         wfDeprecated( __METHOD__, '1.21' );
1748
1749         return MessageCache::singleton()->get( $key, /*useDB*/true, /*content*/false ) === false;
1750 }
1751
1752 /**
1753  * Throw a debugging exception. This function previously once exited the process,
1754  * but now throws an exception instead, with similar results.
1755  *
1756  * @param $msg String: message shown when dying.
1757  * @throws MWException
1758  */
1759 function wfDebugDieBacktrace( $msg = '' ) {
1760         throw new MWException( $msg );
1761 }
1762
1763 /**
1764  * Fetch server name for use in error reporting etc.
1765  * Use real server name if available, so we know which machine
1766  * in a server farm generated the current page.
1767  *
1768  * @return string
1769  */
1770 function wfHostname() {
1771         static $host;
1772         if ( is_null( $host ) ) {
1773
1774                 # Hostname overriding
1775                 global $wgOverrideHostname;
1776                 if( $wgOverrideHostname !== false ) {
1777                         # Set static and skip any detection
1778                         $host = $wgOverrideHostname;
1779                         return $host;
1780                 }
1781
1782                 if ( function_exists( 'posix_uname' ) ) {
1783                         // This function not present on Windows
1784                         $uname = posix_uname();
1785                 } else {
1786                         $uname = false;
1787                 }
1788                 if( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1789                         $host = $uname['nodename'];
1790                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1791                         # Windows computer name
1792                         $host = getenv( 'COMPUTERNAME' );
1793                 } else {
1794                         # This may be a virtual server.
1795                         $host = $_SERVER['SERVER_NAME'];
1796                 }
1797         }
1798         return $host;
1799 }
1800
1801 /**
1802  * Returns a HTML comment with the elapsed time since request.
1803  * This method has no side effects.
1804  *
1805  * @return string
1806  */
1807 function wfReportTime() {
1808         global $wgRequestTime, $wgShowHostnames;
1809
1810         $elapsed = microtime( true ) - $wgRequestTime;
1811
1812         return $wgShowHostnames
1813                 ? sprintf( '<!-- Served by %s in %01.3f secs. -->', wfHostname(), $elapsed )
1814                 : sprintf( '<!-- Served in %01.3f secs. -->', $elapsed );
1815 }
1816
1817 /**
1818  * Safety wrapper for debug_backtrace().
1819  *
1820  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
1821  * murky circumstances, which may be triggered in part by stub objects
1822  * or other fancy talkin'.
1823  *
1824  * Will return an empty array if Zend Optimizer is detected or if
1825  * debug_backtrace is disabled, otherwise the output from
1826  * debug_backtrace() (trimmed).
1827  *
1828  * @param $limit int This parameter can be used to limit the number of stack frames returned
1829  *
1830  * @return array of backtrace information
1831  */
1832 function wfDebugBacktrace( $limit = 0 ) {
1833         static $disabled = null;
1834
1835         if( extension_loaded( 'Zend Optimizer' ) ) {
1836                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
1837                 return array();
1838         }
1839
1840         if ( is_null( $disabled ) ) {
1841                 $disabled = false;
1842                 $functions = explode( ',', ini_get( 'disable_functions' ) );
1843                 $functions = array_map( 'trim', $functions );
1844                 $functions = array_map( 'strtolower', $functions );
1845                 if ( in_array( 'debug_backtrace', $functions ) ) {
1846                         wfDebug( "debug_backtrace is in disabled_functions\n" );
1847                         $disabled = true;
1848                 }
1849         }
1850         if ( $disabled ) {
1851                 return array();
1852         }
1853
1854         if ( $limit && version_compare( PHP_VERSION, '5.4.0', '>=' ) ) {
1855                 return array_slice( debug_backtrace( DEBUG_BACKTRACE_PROVIDE_OBJECT, $limit + 1 ), 1 );
1856         } else {
1857                 return array_slice( debug_backtrace(), 1 );
1858         }
1859 }
1860
1861 /**
1862  * Get a debug backtrace as a string
1863  *
1864  * @return string
1865  */
1866 function wfBacktrace() {
1867         global $wgCommandLineMode;
1868
1869         if ( $wgCommandLineMode ) {
1870                 $msg = '';
1871         } else {
1872                 $msg = "<ul>\n";
1873         }
1874         $backtrace = wfDebugBacktrace();
1875         foreach( $backtrace as $call ) {
1876                 if( isset( $call['file'] ) ) {
1877                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
1878                         $file = $f[count( $f ) - 1];
1879                 } else {
1880                         $file = '-';
1881                 }
1882                 if( isset( $call['line'] ) ) {
1883                         $line = $call['line'];
1884                 } else {
1885                         $line = '-';
1886                 }
1887                 if ( $wgCommandLineMode ) {
1888                         $msg .= "$file line $line calls ";
1889                 } else {
1890                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
1891                 }
1892                 if( !empty( $call['class'] ) ) {
1893                         $msg .= $call['class'] . $call['type'];
1894                 }
1895                 $msg .= $call['function'] . '()';
1896
1897                 if ( $wgCommandLineMode ) {
1898                         $msg .= "\n";
1899                 } else {
1900                         $msg .= "</li>\n";
1901                 }
1902         }
1903         if ( $wgCommandLineMode ) {
1904                 $msg .= "\n";
1905         } else {
1906                 $msg .= "</ul>\n";
1907         }
1908
1909         return $msg;
1910 }
1911
1912 /**
1913  * Get the name of the function which called this function
1914  * wfGetCaller( 1 ) is the function with the wfGetCaller() call (ie. __FUNCTION__)
1915  * wfGetCaller( 2 ) [default] is the caller of the function running wfGetCaller()
1916  * wfGetCaller( 3 ) is the parent of that.
1917  *
1918  * @param $level Int
1919  * @return string
1920  */
1921 function wfGetCaller( $level = 2 ) {
1922         $backtrace = wfDebugBacktrace( $level + 1 );
1923         if ( isset( $backtrace[$level] ) ) {
1924                 return wfFormatStackFrame( $backtrace[$level] );
1925         } else {
1926                 return 'unknown';
1927         }
1928 }
1929
1930 /**
1931  * Return a string consisting of callers in the stack. Useful sometimes
1932  * for profiling specific points.
1933  *
1934  * @param $limit int The maximum depth of the stack frame to return, or false for
1935  *               the entire stack.
1936  * @return String
1937  */
1938 function wfGetAllCallers( $limit = 3 ) {
1939         $trace = array_reverse( wfDebugBacktrace() );
1940         if ( !$limit || $limit > count( $trace ) - 1 ) {
1941                 $limit = count( $trace ) - 1;
1942         }
1943         $trace = array_slice( $trace, -$limit - 1, $limit );
1944         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1945 }
1946
1947 /**
1948  * Return a string representation of frame
1949  *
1950  * @param $frame Array
1951  * @return string
1952  */
1953 function wfFormatStackFrame( $frame ) {
1954         return isset( $frame['class'] ) ?
1955                 $frame['class'] . '::' . $frame['function'] :
1956                 $frame['function'];
1957 }
1958
1959
1960 /* Some generic result counters, pulled out of SearchEngine */
1961
1962
1963 /**
1964  * @todo document
1965  *
1966  * @param $offset Int
1967  * @param $limit Int
1968  * @return String
1969  */
1970 function wfShowingResults( $offset, $limit ) {
1971         return wfMessage( 'showingresults' )->numParams( $limit, $offset + 1 )->parse();
1972 }
1973
1974 /**
1975  * Generate (prev x| next x) (20|50|100...) type links for paging
1976  *
1977  * @param $offset String
1978  * @param $limit Integer
1979  * @param $link String
1980  * @param $query String: optional URL query parameter string
1981  * @param $atend Bool: optional param for specified if this is the last page
1982  * @return String
1983  * @deprecated in 1.19; use Language::viewPrevNext() instead
1984  */
1985 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
1986         wfDeprecated( __METHOD__, '1.19' );
1987
1988         global $wgLang;
1989
1990         $query = wfCgiToArray( $query );
1991
1992         if( is_object( $link ) ) {
1993                 $title = $link;
1994         } else {
1995                 $title = Title::newFromText( $link );
1996                 if( is_null( $title ) ) {
1997                         return false;
1998                 }
1999         }
2000
2001         return $wgLang->viewPrevNext( $title, $offset, $limit, $query, $atend );
2002 }
2003
2004 /**
2005  * Make a list item, used by various special pages
2006  *
2007  * @param $page String Page link
2008  * @param $details String Text between brackets
2009  * @param $oppositedm Boolean   Add the direction mark opposite to your
2010  *                                                              language, to display text properly
2011  * @return String
2012  * @deprecated since 1.19; use Language::specialList() instead
2013  */
2014 function wfSpecialList( $page, $details, $oppositedm = true ) {
2015         wfDeprecated( __METHOD__, '1.19' );
2016
2017         global $wgLang;
2018         return $wgLang->specialList( $page, $details, $oppositedm );
2019 }
2020
2021 /**
2022  * @todo document
2023  * @todo FIXME: We may want to blacklist some broken browsers
2024  *
2025  * @param $force Bool
2026  * @return bool Whereas client accept gzip compression
2027  */
2028 function wfClientAcceptsGzip( $force = false ) {
2029         static $result = null;
2030         if ( $result === null || $force ) {
2031                 $result = false;
2032                 if( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
2033                         # @todo FIXME: We may want to blacklist some broken browsers
2034                         $m = array();
2035                         if( preg_match(
2036                                 '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
2037                                 $_SERVER['HTTP_ACCEPT_ENCODING'],
2038                                 $m )
2039                         )
2040                         {
2041                                 if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
2042                                         $result = false;
2043                                         return $result;
2044                                 }
2045                                 wfDebug( "wfClientAcceptsGzip: client accepts gzip.\n" );
2046                                 $result = true;
2047                         }
2048                 }
2049         }
2050         return $result;
2051 }
2052
2053 /**
2054  * Obtain the offset and limit values from the request string;
2055  * used in special pages
2056  *
2057  * @param $deflimit Int default limit if none supplied
2058  * @param $optionname String Name of a user preference to check against
2059  * @return array
2060  *
2061  */
2062 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
2063         global $wgRequest;
2064         return $wgRequest->getLimitOffset( $deflimit, $optionname );
2065 }
2066
2067 /**
2068  * Escapes the given text so that it may be output using addWikiText()
2069  * without any linking, formatting, etc. making its way through. This
2070  * is achieved by substituting certain characters with HTML entities.
2071  * As required by the callers, "<nowiki>" is not used.
2072  *
2073  * @param $text String: text to be escaped
2074  * @return String
2075  */
2076 function wfEscapeWikiText( $text ) {
2077         $text = strtr( "\n$text", array(
2078                 '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
2079                 '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
2080                 '{' => '&#123;', '|' => '&#124;', '}' => '&#125;',
2081                 "\n#" => "\n&#35;", "\n*" => "\n&#42;",
2082                 "\n:" => "\n&#58;", "\n;" => "\n&#59;",
2083                 '://' => '&#58;//', 'ISBN ' => 'ISBN&#32;', 'RFC ' => 'RFC&#32;',
2084         ) );
2085         return substr( $text, 1 );
2086 }
2087
2088 /**
2089  * Get the current unix timetstamp with microseconds.  Useful for profiling
2090  * @return Float
2091  */
2092 function wfTime() {
2093         return microtime( true );
2094 }
2095
2096 /**
2097  * Sets dest to source and returns the original value of dest
2098  * If source is NULL, it just returns the value, it doesn't set the variable
2099  * If force is true, it will set the value even if source is NULL
2100  *
2101  * @param $dest Mixed
2102  * @param $source Mixed
2103  * @param $force Bool
2104  * @return Mixed
2105  */
2106 function wfSetVar( &$dest, $source, $force = false ) {
2107         $temp = $dest;
2108         if ( !is_null( $source ) || $force ) {
2109                 $dest = $source;
2110         }
2111         return $temp;
2112 }
2113
2114 /**
2115  * As for wfSetVar except setting a bit
2116  *
2117  * @param $dest Int
2118  * @param $bit Int
2119  * @param $state Bool
2120  *
2121  * @return bool
2122  */
2123 function wfSetBit( &$dest, $bit, $state = true ) {
2124         $temp = (bool)( $dest & $bit );
2125         if ( !is_null( $state ) ) {
2126                 if ( $state ) {
2127                         $dest |= $bit;
2128                 } else {
2129                         $dest &= ~$bit;
2130                 }
2131         }
2132         return $temp;
2133 }
2134
2135 /**
2136  * A wrapper around the PHP function var_export().
2137  * Either print it or add it to the regular output ($wgOut).
2138  *
2139  * @param $var mixed A PHP variable to dump.
2140  */
2141 function wfVarDump( $var ) {
2142         global $wgOut;
2143         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
2144         if ( headers_sent() || !isset( $wgOut ) || !is_object( $wgOut ) ) {
2145                 print $s;
2146         } else {
2147                 $wgOut->addHTML( $s );
2148         }
2149 }
2150
2151 /**
2152  * Provide a simple HTTP error.
2153  *
2154  * @param $code Int|String
2155  * @param $label String
2156  * @param $desc String
2157  */
2158 function wfHttpError( $code, $label, $desc ) {
2159         global $wgOut;
2160         $wgOut->disable();
2161         header( "HTTP/1.0 $code $label" );
2162         header( "Status: $code $label" );
2163         $wgOut->sendCacheControl();
2164
2165         header( 'Content-type: text/html; charset=utf-8' );
2166         print "<!doctype html>" .
2167                 '<html><head><title>' .
2168                 htmlspecialchars( $label ) .
2169                 '</title></head><body><h1>' .
2170                 htmlspecialchars( $label ) .
2171                 '</h1><p>' .
2172                 nl2br( htmlspecialchars( $desc ) ) .
2173                 "</p></body></html>\n";
2174 }
2175
2176 /**
2177  * Clear away any user-level output buffers, discarding contents.
2178  *
2179  * Suitable for 'starting afresh', for instance when streaming
2180  * relatively large amounts of data without buffering, or wanting to
2181  * output image files without ob_gzhandler's compression.
2182  *
2183  * The optional $resetGzipEncoding parameter controls suppression of
2184  * the Content-Encoding header sent by ob_gzhandler; by default it
2185  * is left. See comments for wfClearOutputBuffers() for why it would
2186  * be used.
2187  *
2188  * Note that some PHP configuration options may add output buffer
2189  * layers which cannot be removed; these are left in place.
2190  *
2191  * @param $resetGzipEncoding Bool
2192  */
2193 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
2194         if( $resetGzipEncoding ) {
2195                 // Suppress Content-Encoding and Content-Length
2196                 // headers from 1.10+s wfOutputHandler
2197                 global $wgDisableOutputCompression;
2198                 $wgDisableOutputCompression = true;
2199         }
2200         while( $status = ob_get_status() ) {
2201                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
2202                         // Probably from zlib.output_compression or other
2203                         // PHP-internal setting which can't be removed.
2204                         //
2205                         // Give up, and hope the result doesn't break
2206                         // output behavior.
2207                         break;
2208                 }
2209                 if( !ob_end_clean() ) {
2210                         // Could not remove output buffer handler; abort now
2211                         // to avoid getting in some kind of infinite loop.
2212                         break;
2213                 }
2214                 if( $resetGzipEncoding ) {
2215                         if( $status['name'] == 'ob_gzhandler' ) {
2216                                 // Reset the 'Content-Encoding' field set by this handler
2217                                 // so we can start fresh.
2218                                 header_remove( 'Content-Encoding' );
2219                                 break;
2220                         }
2221                 }
2222         }
2223 }
2224
2225 /**
2226  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
2227  *
2228  * Clear away output buffers, but keep the Content-Encoding header
2229  * produced by ob_gzhandler, if any.
2230  *
2231  * This should be used for HTTP 304 responses, where you need to
2232  * preserve the Content-Encoding header of the real result, but
2233  * also need to suppress the output of ob_gzhandler to keep to spec
2234  * and avoid breaking Firefox in rare cases where the headers and
2235  * body are broken over two packets.
2236  */
2237 function wfClearOutputBuffers() {
2238         wfResetOutputBuffers( false );
2239 }
2240
2241 /**
2242  * Converts an Accept-* header into an array mapping string values to quality
2243  * factors
2244  *
2245  * @param $accept String
2246  * @param $def String default
2247  * @return Array
2248  */
2249 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
2250         # No arg means accept anything (per HTTP spec)
2251         if( !$accept ) {
2252                 return array( $def => 1.0 );
2253         }
2254
2255         $prefs = array();
2256
2257         $parts = explode( ',', $accept );
2258
2259         foreach( $parts as $part ) {
2260                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
2261                 $values = explode( ';', trim( $part ) );
2262                 $match = array();
2263                 if ( count( $values ) == 1 ) {
2264                         $prefs[$values[0]] = 1.0;
2265                 } elseif ( preg_match( '/q\s*=\s*(\d*\.\d+)/', $values[1], $match ) ) {
2266                         $prefs[$values[0]] = floatval( $match[1] );
2267                 }
2268         }
2269
2270         return $prefs;
2271 }
2272
2273 /**
2274  * Checks if a given MIME type matches any of the keys in the given
2275  * array. Basic wildcards are accepted in the array keys.
2276  *
2277  * Returns the matching MIME type (or wildcard) if a match, otherwise
2278  * NULL if no match.
2279  *
2280  * @param $type String
2281  * @param $avail Array
2282  * @return string
2283  * @private
2284  */
2285 function mimeTypeMatch( $type, $avail ) {
2286         if( array_key_exists( $type, $avail ) ) {
2287                 return $type;
2288         } else {
2289                 $parts = explode( '/', $type );
2290                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
2291                         return $parts[0] . '/*';
2292                 } elseif( array_key_exists( '*/*', $avail ) ) {
2293                         return '*/*';
2294                 } else {
2295                         return null;
2296                 }
2297         }
2298 }
2299
2300 /**
2301  * Returns the 'best' match between a client's requested internet media types
2302  * and the server's list of available types. Each list should be an associative
2303  * array of type to preference (preference is a float between 0.0 and 1.0).
2304  * Wildcards in the types are acceptable.
2305  *
2306  * @param $cprefs Array: client's acceptable type list
2307  * @param $sprefs Array: server's offered types
2308  * @return string
2309  *
2310  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
2311  * XXX: generalize to negotiate other stuff
2312  */
2313 function wfNegotiateType( $cprefs, $sprefs ) {
2314         $combine = array();
2315
2316         foreach( array_keys( $sprefs ) as $type ) {
2317                 $parts = explode( '/', $type );
2318                 if( $parts[1] != '*' ) {
2319                         $ckey = mimeTypeMatch( $type, $cprefs );
2320                         if( $ckey ) {
2321                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
2322                         }
2323                 }
2324         }
2325
2326         foreach( array_keys( $cprefs ) as $type ) {
2327                 $parts = explode( '/', $type );
2328                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
2329                         $skey = mimeTypeMatch( $type, $sprefs );
2330                         if( $skey ) {
2331                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
2332                         }
2333                 }
2334         }
2335
2336         $bestq = 0;
2337         $besttype = null;
2338
2339         foreach( array_keys( $combine ) as $type ) {
2340                 if( $combine[$type] > $bestq ) {
2341                         $besttype = $type;
2342                         $bestq = $combine[$type];
2343                 }
2344         }
2345
2346         return $besttype;
2347 }
2348
2349 /**
2350  * Reference-counted warning suppression
2351  *
2352  * @param $end Bool
2353  */
2354 function wfSuppressWarnings( $end = false ) {
2355         static $suppressCount = 0;
2356         static $originalLevel = false;
2357
2358         if ( $end ) {
2359                 if ( $suppressCount ) {
2360                         --$suppressCount;
2361                         if ( !$suppressCount ) {
2362                                 error_reporting( $originalLevel );
2363                         }
2364                 }
2365         } else {
2366                 if ( !$suppressCount ) {
2367                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE | E_USER_WARNING | E_USER_NOTICE | E_DEPRECATED | E_USER_DEPRECATED | E_STRICT ) );
2368                 }
2369                 ++$suppressCount;
2370         }
2371 }
2372
2373 /**
2374  * Restore error level to previous value
2375  */
2376 function wfRestoreWarnings() {
2377         wfSuppressWarnings( true );
2378 }
2379
2380 # Autodetect, convert and provide timestamps of various types
2381
2382 /**
2383  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
2384  */
2385 define( 'TS_UNIX', 0 );
2386
2387 /**
2388  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
2389  */
2390 define( 'TS_MW', 1 );
2391
2392 /**
2393  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
2394  */
2395 define( 'TS_DB', 2 );
2396
2397 /**
2398  * RFC 2822 format, for E-mail and HTTP headers
2399  */
2400 define( 'TS_RFC2822', 3 );
2401
2402 /**
2403  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
2404  *
2405  * This is used by Special:Export
2406  */
2407 define( 'TS_ISO_8601', 4 );
2408
2409 /**
2410  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
2411  *
2412  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
2413  *       DateTime tag and page 36 for the DateTimeOriginal and
2414  *       DateTimeDigitized tags.
2415  */
2416 define( 'TS_EXIF', 5 );
2417
2418 /**
2419  * Oracle format time.
2420  */
2421 define( 'TS_ORACLE', 6 );
2422
2423 /**
2424  * Postgres format time.
2425  */
2426 define( 'TS_POSTGRES', 7 );
2427
2428 /**
2429  * DB2 format time
2430  */
2431 define( 'TS_DB2', 8 );
2432
2433 /**
2434  * ISO 8601 basic format with no timezone: 19860209T200000Z.  This is used by ResourceLoader
2435  */
2436 define( 'TS_ISO_8601_BASIC', 9 );
2437
2438 /**
2439  * Get a timestamp string in one of various formats
2440  *
2441  * @param $outputtype Mixed: A timestamp in one of the supported formats, the
2442  *                    function will autodetect which format is supplied and act
2443  *                    accordingly.
2444  * @param $ts Mixed: optional timestamp to convert, default 0 for the current time
2445  * @return Mixed: String / false The same date in the format specified in $outputtype or false
2446  */
2447 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
2448         try {
2449                 $timestamp = new MWTimestamp( $ts );
2450                 return $timestamp->getTimestamp( $outputtype );
2451         } catch( TimestampException $e ) {
2452                 wfDebug( "wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n" );
2453                 return false;
2454         }
2455 }
2456
2457 /**
2458  * Return a formatted timestamp, or null if input is null.
2459  * For dealing with nullable timestamp columns in the database.
2460  *
2461  * @param $outputtype Integer
2462  * @param $ts String
2463  * @return String
2464  */
2465 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2466         if( is_null( $ts ) ) {
2467                 return null;
2468         } else {
2469                 return wfTimestamp( $outputtype, $ts );
2470         }
2471 }
2472
2473 /**
2474  * Convenience function; returns MediaWiki timestamp for the present time.
2475  *
2476  * @return string
2477  */
2478 function wfTimestampNow() {
2479         # return NOW
2480         return wfTimestamp( TS_MW, time() );
2481 }
2482
2483 /**
2484  * Check if the operating system is Windows
2485  *
2486  * @return Bool: true if it's Windows, False otherwise.
2487  */
2488 function wfIsWindows() {
2489         static $isWindows = null;
2490         if ( $isWindows === null ) {
2491                 $isWindows = substr( php_uname(), 0, 7 ) == 'Windows';
2492         }
2493         return $isWindows;
2494 }
2495
2496 /**
2497  * Check if we are running under HipHop
2498  *
2499  * @return Bool
2500  */
2501 function wfIsHipHop() {
2502         return function_exists( 'hphp_thread_set_warmup_enabled' );
2503 }
2504
2505 /**
2506  * Swap two variables
2507  *
2508  * @param $x Mixed
2509  * @param $y Mixed
2510  */
2511 function swap( &$x, &$y ) {
2512         $z = $x;
2513         $x = $y;
2514         $y = $z;
2515 }
2516
2517 /**
2518  * Tries to get the system directory for temporary files. First
2519  * $wgTmpDirectory is checked, and then the TMPDIR, TMP, and TEMP
2520  * environment variables are then checked in sequence, and if none are
2521  * set try sys_get_temp_dir().
2522  *
2523  * NOTE: When possible, use instead the tmpfile() function to create
2524  * temporary files to avoid race conditions on file creation, etc.
2525  *
2526  * @return String
2527  */
2528 function wfTempDir() {
2529         global $wgTmpDirectory;
2530
2531         if ( $wgTmpDirectory !== false ) {
2532                 return $wgTmpDirectory;
2533         }
2534
2535         $tmpDir = array_map( "getenv", array( 'TMPDIR', 'TMP', 'TEMP' ) );
2536
2537         foreach( $tmpDir as $tmp ) {
2538                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
2539                         return $tmp;
2540                 }
2541         }
2542         return sys_get_temp_dir();
2543 }
2544
2545 /**
2546  * Make directory, and make all parent directories if they don't exist
2547  *
2548  * @param $dir String: full path to directory to create
2549  * @param $mode Integer: chmod value to use, default is $wgDirectoryMode
2550  * @param $caller String: optional caller param for debugging.
2551  * @throws MWException
2552  * @return bool
2553  */
2554 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2555         global $wgDirectoryMode;
2556
2557         if ( FileBackend::isStoragePath( $dir ) ) { // sanity
2558                 throw new MWException( __FUNCTION__ . " given storage path '$dir'." );
2559         }
2560
2561         if ( !is_null( $caller ) ) {
2562                 wfDebug( "$caller: called wfMkdirParents($dir)\n" );
2563         }
2564
2565         if( strval( $dir ) === '' || file_exists( $dir ) ) {
2566                 return true;
2567         }
2568
2569         $dir = str_replace( array( '\\', '/' ), DIRECTORY_SEPARATOR, $dir );
2570
2571         if ( is_null( $mode ) ) {
2572                 $mode = $wgDirectoryMode;
2573         }
2574
2575         // Turn off the normal warning, we're doing our own below
2576         wfSuppressWarnings();
2577         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2578         wfRestoreWarnings();
2579
2580         if( !$ok ) {
2581                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2582                 trigger_error( sprintf( "%s: failed to mkdir \"%s\" mode 0%o", __FUNCTION__, $dir, $mode ),
2583                         E_USER_WARNING );
2584         }
2585         return $ok;
2586 }
2587
2588 /**
2589  * Remove a directory and all its content.
2590  * Does not hide error.
2591  */
2592 function wfRecursiveRemoveDir( $dir ) {
2593         wfDebug( __FUNCTION__ . "( $dir )\n" );
2594         // taken from http://de3.php.net/manual/en/function.rmdir.php#98622
2595         if ( is_dir( $dir ) ) {
2596                 $objects = scandir( $dir );
2597                 foreach ( $objects as $object ) {
2598                         if ( $object != "." && $object != ".." ) {
2599                                 if ( filetype( $dir . '/' . $object ) == "dir" ) {
2600                                         wfRecursiveRemoveDir( $dir . '/' . $object );
2601                                 } else {
2602                                         unlink( $dir . '/' . $object );
2603                                 }
2604                         }
2605                 }
2606                 reset( $objects );
2607                 rmdir( $dir );
2608         }
2609 }
2610
2611 /**
2612  * @param $nr Mixed: the number to format
2613  * @param $acc Integer: the number of digits after the decimal point, default 2
2614  * @param $round Boolean: whether or not to round the value, default true
2615  * @return float
2616  */
2617 function wfPercent( $nr, $acc = 2, $round = true ) {
2618         $ret = sprintf( "%.${acc}f", $nr );
2619         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2620 }
2621
2622 /**
2623  * Find out whether or not a mixed variable exists in a string
2624  *
2625  * @deprecated Just use str(i)pos
2626  * @param $needle String
2627  * @param $str String
2628  * @param $insensitive Boolean
2629  * @return Boolean
2630  */
2631 function in_string( $needle, $str, $insensitive = false ) {
2632         wfDeprecated( __METHOD__, '1.21' );
2633         $func = 'strpos';
2634         if( $insensitive ) $func = 'stripos';
2635
2636         return $func( $str, $needle ) !== false;
2637 }
2638
2639 /**
2640  * Safety wrapper around ini_get() for boolean settings.
2641  * The values returned from ini_get() are pre-normalized for settings
2642  * set via php.ini or php_flag/php_admin_flag... but *not*
2643  * for those set via php_value/php_admin_value.
2644  *
2645  * It's fairly common for people to use php_value instead of php_flag,
2646  * which can leave you with an 'off' setting giving a false positive
2647  * for code that just takes the ini_get() return value as a boolean.
2648  *
2649  * To make things extra interesting, setting via php_value accepts
2650  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2651  * Unrecognized values go false... again opposite PHP's own coercion
2652  * from string to bool.
2653  *
2654  * Luckily, 'properly' set settings will always come back as '0' or '1',
2655  * so we only have to worry about them and the 'improper' settings.
2656  *
2657  * I frickin' hate PHP... :P
2658  *
2659  * @param $setting String
2660  * @return Bool
2661  */
2662 function wfIniGetBool( $setting ) {
2663         $val = ini_get( $setting );
2664         // 'on' and 'true' can't have whitespace around them, but '1' can.
2665         return strtolower( $val ) == 'on'
2666                 || strtolower( $val ) == 'true'
2667                 || strtolower( $val ) == 'yes'
2668                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2669 }
2670
2671 /**
2672  * Wrapper function for PHP's dl(). This doesn't work in most situations from
2673  * PHP 5.3 onward, and is usually disabled in shared environments anyway.
2674  *
2675  * @param $extension String A PHP extension. The file suffix (.so or .dll)
2676  *                          should be omitted
2677  * @param $fileName String Name of the library, if not $extension.suffix
2678  * @return Bool - Whether or not the extension is loaded
2679  */
2680 function wfDl( $extension, $fileName = null ) {
2681         if( extension_loaded( $extension ) ) {
2682                 return true;
2683         }
2684
2685         $canDl = false;
2686         if( PHP_SAPI == 'cli' || PHP_SAPI == 'cgi' || PHP_SAPI == 'embed' ) {
2687                 $canDl = ( function_exists( 'dl' ) && is_callable( 'dl' )
2688                 && wfIniGetBool( 'enable_dl' ) && !wfIniGetBool( 'safe_mode' ) );
2689         }
2690
2691         if( $canDl ) {
2692                 $fileName = $fileName ? $fileName : $extension;
2693                 if( wfIsWindows() ) {
2694                         $fileName = 'php_' . $fileName;
2695                 }
2696                 wfSuppressWarnings();
2697                 dl( $fileName . '.' . PHP_SHLIB_SUFFIX );
2698                 wfRestoreWarnings();
2699         }
2700         return extension_loaded( $extension );
2701 }
2702
2703 /**
2704  * Windows-compatible version of escapeshellarg()
2705  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
2706  * function puts single quotes in regardless of OS.
2707  *
2708  * Also fixes the locale problems on Linux in PHP 5.2.6+ (bug backported to
2709  * earlier distro releases of PHP)
2710  *
2711  * @param varargs
2712  * @return String
2713  */
2714 function wfEscapeShellArg( ) {
2715         wfInitShellLocale();
2716
2717         $args = func_get_args();
2718         $first = true;
2719         $retVal = '';
2720         foreach ( $args as $arg ) {
2721                 if ( !$first ) {
2722                         $retVal .= ' ';
2723                 } else {
2724                         $first = false;
2725                 }
2726
2727                 if ( wfIsWindows() ) {
2728                         // Escaping for an MSVC-style command line parser and CMD.EXE
2729                         // Refs:
2730                         //  * http://web.archive.org/web/20020708081031/http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
2731                         //  * http://technet.microsoft.com/en-us/library/cc723564.aspx
2732                         //  * Bug #13518
2733                         //  * CR r63214
2734                         // Double the backslashes before any double quotes. Escape the double quotes.
2735                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
2736                         $arg = '';
2737                         $iteration = 0;
2738                         foreach ( $tokens as $token ) {
2739                                 if ( $iteration % 2 == 1 ) {
2740                                         // Delimiter, a double quote preceded by zero or more slashes
2741                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
2742                                 } elseif ( $iteration % 4 == 2 ) {
2743                                         // ^ in $token will be outside quotes, need to be escaped
2744                                         $arg .= str_replace( '^', '^^', $token );
2745                                 } else { // $iteration % 4 == 0
2746                                         // ^ in $token will appear inside double quotes, so leave as is
2747                                         $arg .= $token;
2748                                 }
2749                                 $iteration++;
2750                         }
2751                         // Double the backslashes before the end of the string, because
2752                         // we will soon add a quote
2753                         $m = array();
2754                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
2755                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
2756                         }
2757
2758                         // Add surrounding quotes
2759                         $retVal .= '"' . $arg . '"';
2760                 } else {
2761                         $retVal .= escapeshellarg( $arg );
2762                 }
2763         }
2764         return $retVal;
2765 }
2766
2767 /**
2768  * Execute a shell command, with time and memory limits mirrored from the PHP
2769  * configuration if supported.
2770  * @param $cmd String Command line, properly escaped for shell.
2771  * @param &$retval null|Mixed optional, will receive the program's exit code.
2772  *                 (non-zero is usually failure)
2773  * @param $environ Array optional environment variables which should be
2774  *                 added to the executed command environment.
2775  * @param $limits Array optional array with limits(filesize, memory, time, walltime)
2776  *                 this overwrites the global wgShellMax* limits.
2777  * @return string collected stdout as a string (trailing newlines stripped)
2778  */
2779 function wfShellExec( $cmd, &$retval = null, $environ = array(), $limits = array() ) {
2780         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize, $wgMaxShellTime,
2781                 $wgMaxShellWallClockTime, $wgShellCgroup;
2782
2783         static $disabled;
2784         if ( is_null( $disabled ) ) {
2785                 $disabled = false;
2786                 if( wfIniGetBool( 'safe_mode' ) ) {
2787                         wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
2788                         $disabled = 'safemode';
2789                 } else {
2790                         $functions = explode( ',', ini_get( 'disable_functions' ) );
2791                         $functions = array_map( 'trim', $functions );
2792                         $functions = array_map( 'strtolower', $functions );
2793                         if ( in_array( 'passthru', $functions ) ) {
2794                                 wfDebug( "passthru is in disabled_functions\n" );
2795                                 $disabled = 'passthru';
2796                         }
2797                 }
2798         }
2799         if ( $disabled ) {
2800                 $retval = 1;
2801                 return $disabled == 'safemode' ?
2802                         'Unable to run external programs in safe mode.' :
2803                         'Unable to run external programs, passthru() is disabled.';
2804         }
2805
2806         wfInitShellLocale();
2807
2808         $envcmd = '';
2809         foreach( $environ as $k => $v ) {
2810                 if ( wfIsWindows() ) {
2811                         /* Surrounding a set in quotes (method used by wfEscapeShellArg) makes the quotes themselves
2812                          * appear in the environment variable, so we must use carat escaping as documented in
2813                          * http://technet.microsoft.com/en-us/library/cc723564.aspx
2814                          * Note however that the quote isn't listed there, but is needed, and the parentheses
2815                          * are listed there but doesn't appear to need it.
2816                          */
2817                         $envcmd .= "set $k=" . preg_replace( '/([&|()<>^"])/', '^\\1', $v ) . '&& ';
2818                 } else {
2819                         /* Assume this is a POSIX shell, thus required to accept variable assignments before the command
2820                          * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_09_01
2821                          */
2822                         $envcmd .= "$k=" . escapeshellarg( $v ) . ' ';
2823                 }
2824         }
2825         $cmd = $envcmd . $cmd;
2826
2827         if ( php_uname( 's' ) == 'Linux' ) {
2828                 $time = intval ( isset( $limits['time'] ) ? $limits['time'] : $wgMaxShellTime );
2829                 if ( isset( $limits['walltime'] ) ) {
2830                         $wallTime = intval( $limits['walltime'] );
2831                 } elseif ( isset( $limits['time'] ) ) {
2832                         $wallTime = $time;
2833                 } else {
2834                         $wallTime = intval( $wgMaxShellWallClockTime );
2835                 }
2836                 $mem = intval ( isset( $limits['memory'] ) ? $limits['memory'] : $wgMaxShellMemory );
2837                 $filesize = intval ( isset( $limits['filesize'] ) ? $limits['filesize'] : $wgMaxShellFileSize );
2838
2839                 if ( $time > 0 || $mem > 0 || $filesize > 0 || $wallTime > 0 ) {
2840                         $cmd = '/bin/bash ' . escapeshellarg( "$IP/includes/limit.sh" ) . ' ' .
2841                                 escapeshellarg( $cmd ) . ' ' .
2842                                 escapeshellarg(
2843                                         "MW_CPU_LIMIT=$time; " .
2844                                         'MW_CGROUP=' . escapeshellarg( $wgShellCgroup ) . '; ' .
2845                                         "MW_MEM_LIMIT=$mem; " .
2846                                         "MW_FILE_SIZE_LIMIT=$filesize; " .
2847                                         "MW_WALL_CLOCK_LIMIT=$wallTime"
2848                                 );
2849                 }
2850         }
2851         wfDebug( "wfShellExec: $cmd\n" );
2852
2853         $retval = 1; // error by default?
2854         ob_start();
2855         passthru( $cmd, $retval );
2856         $output = ob_get_contents();
2857         ob_end_clean();
2858
2859         if ( $retval == 127 ) {
2860                 wfDebugLog( 'exec', "Possibly missing executable file: $cmd\n" );
2861         }
2862         return $output;
2863 }
2864
2865 /**
2866  * Workaround for http://bugs.php.net/bug.php?id=45132
2867  * escapeshellarg() destroys non-ASCII characters if LANG is not a UTF-8 locale
2868  */
2869 function wfInitShellLocale() {
2870         static $done = false;
2871         if ( $done ) {
2872                 return;
2873         }
2874         $done = true;
2875         global $wgShellLocale;
2876         if ( !wfIniGetBool( 'safe_mode' ) ) {
2877                 putenv( "LC_CTYPE=$wgShellLocale" );
2878                 setlocale( LC_CTYPE, $wgShellLocale );
2879         }
2880 }
2881
2882 /**
2883  * Alias to wfShellWikiCmd()
2884  * @see wfShellWikiCmd()
2885  */
2886 function wfShellMaintenanceCmd( $script, array $parameters = array(), array $options = array() ) {
2887         return wfShellWikiCmd( $script, $parameters, $options );
2888 }
2889
2890 /**
2891  * Generate a shell-escaped command line string to run a MediaWiki cli script.
2892  * Note that $parameters should be a flat array and an option with an argument
2893  * should consist of two consecutive items in the array (do not use "--option value").
2894  * @param $script string MediaWiki cli script path
2895  * @param $parameters Array Arguments and options to the script
2896  * @param $options Array Associative array of options:
2897  *              'php': The path to the php executable
2898  *              'wrapper': Path to a PHP wrapper to handle the maintenance script
2899  * @return Array
2900  */
2901 function wfShellWikiCmd( $script, array $parameters = array(), array $options = array() ) {
2902         global $wgPhpCli;
2903         // Give site config file a chance to run the script in a wrapper.
2904         // The caller may likely want to call wfBasename() on $script.
2905         wfRunHooks( 'wfShellWikiCmd', array( &$script, &$parameters, &$options ) );
2906         $cmd = isset( $options['php'] ) ? array( $options['php'] ) : array( $wgPhpCli );
2907         if ( isset( $options['wrapper'] ) ) {
2908                 $cmd[] = $options['wrapper'];
2909         }
2910         $cmd[] = $script;
2911         // Escape each parameter for shell
2912         return implode( " ", array_map( 'wfEscapeShellArg', array_merge( $cmd, $parameters ) ) );
2913 }
2914
2915 /**
2916  * wfMerge attempts to merge differences between three texts.
2917  * Returns true for a clean merge and false for failure or a conflict.
2918  *
2919  * @param $old String
2920  * @param $mine String
2921  * @param $yours String
2922  * @param $result String
2923  * @return Bool
2924  */
2925 function wfMerge( $old, $mine, $yours, &$result ) {
2926         global $wgDiff3;
2927
2928         # This check may also protect against code injection in
2929         # case of broken installations.
2930         wfSuppressWarnings();
2931         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
2932         wfRestoreWarnings();
2933
2934         if( !$haveDiff3 ) {
2935                 wfDebug( "diff3 not found\n" );
2936                 return false;
2937         }
2938
2939         # Make temporary files
2940         $td = wfTempDir();
2941         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
2942         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
2943         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
2944
2945         # NOTE: diff3 issues a warning to stderr if any of the files does not end with
2946         #       a newline character. To avoid this, we normalize the trailing whitespace before
2947         #       creating the diff.
2948
2949         fwrite( $oldtextFile, rtrim( $old ) . "\n" );
2950         fclose( $oldtextFile );
2951         fwrite( $mytextFile, rtrim( $mine ) . "\n" );
2952         fclose( $mytextFile );
2953         fwrite( $yourtextFile, rtrim( $yours ) . "\n" );
2954         fclose( $yourtextFile );
2955
2956         # Check for a conflict
2957         $cmd = wfEscapeShellArg( $wgDiff3 ) . ' -a --overlap-only ' .
2958                 wfEscapeShellArg( $mytextName ) . ' ' .
2959                 wfEscapeShellArg( $oldtextName ) . ' ' .
2960                 wfEscapeShellArg( $yourtextName );
2961         $handle = popen( $cmd, 'r' );
2962
2963         if( fgets( $handle, 1024 ) ) {
2964                 $conflict = true;
2965         } else {
2966                 $conflict = false;
2967         }
2968         pclose( $handle );
2969
2970         # Merge differences
2971         $cmd = wfEscapeShellArg( $wgDiff3 ) . ' -a -e --merge ' .
2972                 wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
2973         $handle = popen( $cmd, 'r' );
2974         $result = '';
2975         do {
2976                 $data = fread( $handle, 8192 );
2977                 if ( strlen( $data ) == 0 ) {
2978                         break;
2979                 }
2980                 $result .= $data;
2981         } while ( true );
2982         pclose( $handle );
2983         unlink( $mytextName );
2984         unlink( $oldtextName );
2985         unlink( $yourtextName );
2986
2987         if ( $result === '' && $old !== '' && !$conflict ) {
2988                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
2989                 $conflict = true;
2990         }
2991         return !$conflict;
2992 }
2993
2994 /**
2995  * Returns unified plain-text diff of two texts.
2996  * Useful for machine processing of diffs.
2997  *
2998  * @param $before String: the text before the changes.
2999  * @param $after String: the text after the changes.
3000  * @param $params String: command-line options for the diff command.
3001  * @return String: unified diff of $before and $after
3002  */
3003 function wfDiff( $before, $after, $params = '-u' ) {
3004         if ( $before == $after ) {
3005                 return '';
3006         }
3007
3008         global $wgDiff;
3009         wfSuppressWarnings();
3010         $haveDiff = $wgDiff && file_exists( $wgDiff );
3011         wfRestoreWarnings();
3012
3013         # This check may also protect against code injection in
3014         # case of broken installations.
3015         if( !$haveDiff ) {
3016                 wfDebug( "diff executable not found\n" );
3017                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
3018                 $format = new UnifiedDiffFormatter();
3019                 return $format->format( $diffs );
3020         }
3021
3022         # Make temporary files
3023         $td = wfTempDir();
3024         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
3025         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
3026
3027         fwrite( $oldtextFile, $before );
3028         fclose( $oldtextFile );
3029         fwrite( $newtextFile, $after );
3030         fclose( $newtextFile );
3031
3032         // Get the diff of the two files
3033         $cmd = "$wgDiff " . $params . ' ' . wfEscapeShellArg( $oldtextName, $newtextName );
3034
3035         $h = popen( $cmd, 'r' );
3036
3037         $diff = '';
3038
3039         do {
3040                 $data = fread( $h, 8192 );
3041                 if ( strlen( $data ) == 0 ) {
3042                         break;
3043                 }
3044                 $diff .= $data;
3045         } while ( true );
3046
3047         // Clean up
3048         pclose( $h );
3049         unlink( $oldtextName );
3050         unlink( $newtextName );
3051
3052         // Kill the --- and +++ lines. They're not useful.
3053         $diff_lines = explode( "\n", $diff );
3054         if ( strpos( $diff_lines[0], '---' ) === 0 ) {
3055                 unset( $diff_lines[0] );
3056         }
3057         if ( strpos( $diff_lines[1], '+++' ) === 0 ) {
3058                 unset( $diff_lines[1] );
3059         }
3060
3061         $diff = implode( "\n", $diff_lines );
3062
3063         return $diff;
3064 }
3065
3066 /**
3067  * This function works like "use VERSION" in Perl, the program will die with a
3068  * backtrace if the current version of PHP is less than the version provided
3069  *
3070  * This is useful for extensions which due to their nature are not kept in sync
3071  * with releases, and might depend on other versions of PHP than the main code
3072  *
3073  * Note: PHP might die due to parsing errors in some cases before it ever
3074  *       manages to call this function, such is life
3075  *
3076  * @see perldoc -f use
3077  *
3078  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
3079  *                 a float
3080  * @throws MWException
3081  */
3082 function wfUsePHP( $req_ver ) {
3083         $php_ver = PHP_VERSION;
3084
3085         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
3086                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
3087         }
3088 }
3089
3090 /**
3091  * This function works like "use VERSION" in Perl except it checks the version
3092  * of MediaWiki, the program will die with a backtrace if the current version
3093  * of MediaWiki is less than the version provided.
3094  *
3095  * This is useful for extensions which due to their nature are not kept in sync
3096  * with releases
3097  *
3098  * @see perldoc -f use
3099  *
3100  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
3101  *                 a float
3102  * @throws MWException
3103  */
3104 function wfUseMW( $req_ver ) {
3105         global $wgVersion;
3106
3107         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
3108                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
3109         }
3110 }
3111
3112 /**
3113  * Return the final portion of a pathname.
3114  * Reimplemented because PHP5's "basename()" is buggy with multibyte text.
3115  * http://bugs.php.net/bug.php?id=33898
3116  *
3117  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
3118  * We'll consider it so always, as we don't want '\s' in our Unix paths either.
3119  *
3120  * @param $path String
3121  * @param $suffix String: to remove if present
3122  * @return String
3123  */
3124 function wfBaseName( $path, $suffix = '' ) {
3125         $encSuffix = ( $suffix == '' )
3126                 ? ''
3127                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
3128         $matches = array();
3129         if( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
3130                 return $matches[1];
3131         } else {
3132                 return '';
3133         }
3134 }
3135
3136 /**
3137  * Generate a relative path name to the given file.
3138  * May explode on non-matching case-insensitive paths,
3139  * funky symlinks, etc.
3140  *
3141  * @param $path String: absolute destination path including target filename
3142  * @param $from String: Absolute source path, directory only
3143  * @return String
3144  */
3145 function wfRelativePath( $path, $from ) {
3146         // Normalize mixed input on Windows...
3147         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
3148         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
3149
3150         // Trim trailing slashes -- fix for drive root
3151         $path = rtrim( $path, DIRECTORY_SEPARATOR );
3152         $from = rtrim( $from, DIRECTORY_SEPARATOR );
3153
3154         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
3155         $against = explode( DIRECTORY_SEPARATOR, $from );
3156
3157         if( $pieces[0] !== $against[0] ) {
3158                 // Non-matching Windows drive letters?
3159                 // Return a full path.
3160                 return $path;
3161         }
3162
3163         // Trim off common prefix
3164         while( count( $pieces ) && count( $against )
3165                 && $pieces[0] == $against[0] ) {
3166                 array_shift( $pieces );
3167                 array_shift( $against );
3168         }
3169
3170         // relative dots to bump us to the parent
3171         while( count( $against ) ) {
3172                 array_unshift( $pieces, '..' );
3173                 array_shift( $against );
3174         }
3175
3176         array_push( $pieces, wfBaseName( $path ) );
3177
3178         return implode( DIRECTORY_SEPARATOR, $pieces );
3179 }
3180
3181 /**
3182  * Do any deferred updates and clear the list
3183  *
3184  * @deprecated since 1.19
3185  * @see DeferredUpdates::doUpdate()
3186  * @param $commit string
3187  */
3188 function wfDoUpdates( $commit = '' ) {
3189         wfDeprecated( __METHOD__, '1.19' );
3190         DeferredUpdates::doUpdates( $commit );
3191 }
3192
3193 /**
3194  * Convert an arbitrarily-long digit string from one numeric base
3195  * to another, optionally zero-padding to a minimum column width.
3196  *
3197  * Supports base 2 through 36; digit values 10-36 are represented
3198  * as lowercase letters a-z. Input is case-insensitive.
3199  *
3200  * @param string $input Input number
3201  * @param int $sourceBase Base of the input number
3202  * @param int $destBase Desired base of the output
3203  * @param int $pad Minimum number of digits in the output (pad with zeroes)
3204  * @param bool $lowercase Whether to output in lowercase or uppercase
3205  * @param string $engine Either "gmp", "bcmath", or "php"
3206  * @return string|bool The output number as a string, or false on error
3207  */
3208 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1, $lowercase = true, $engine = 'auto' ) {
3209         if(
3210                 $sourceBase < 2 ||
3211                 $sourceBase > 36 ||
3212                 $destBase < 2 ||
3213                 $destBase > 36 ||
3214                 $sourceBase != (int) $sourceBase ||
3215                 $destBase != (int) $destBase ||
3216                 $pad != (int) $pad ||
3217                 !preg_match( "/^[" . substr( '0123456789abcdefghijklmnopqrstuvwxyz', 0, $sourceBase ) . "]+$/i", $input )
3218         ) {
3219                 return false;
3220         }
3221
3222         static $baseChars = array (
3223                 10 => 'a', 11 => 'b', 12 => 'c', 13 => 'd', 14 => 'e', 15 => 'f',
3224                 16 => 'g', 17 => 'h', 18 => 'i', 19 => 'j', 20 => 'k', 21 => 'l',
3225                 22 => 'm', 23 => 'n', 24 => 'o', 25 => 'p', 26 => 'q', 27 => 'r',
3226                 28 => 's', 29 => 't', 30 => 'u', 31 => 'v', 32 => 'w', 33 => 'x',
3227                 34 => 'y', 35 => 'z',
3228
3229                 '0' => 0,  '1' => 1,  '2' => 2,  '3' => 3,  '4' => 4,  '5' => 5,
3230                 '6' => 6,  '7' => 7,  '8' => 8,  '9' => 9,  'a' => 10, 'b' => 11,
3231                 'c' => 12, 'd' => 13, 'e' => 14, 'f' => 15, 'g' => 16, 'h' => 17,
3232                 'i' => 18, 'j' => 19, 'k' => 20, 'l' => 21, 'm' => 22, 'n' => 23,
3233                 'o' => 24, 'p' => 25, 'q' => 26, 'r' => 27, 's' => 28, 't' => 29,
3234                 'u' => 30, 'v' => 31, 'w' => 32, 'x' => 33, 'y' => 34, 'z' => 35
3235         );
3236
3237         if( extension_loaded( 'gmp' ) && ( $engine == 'auto' || $engine == 'gmp' ) ) {
3238                 $result = gmp_strval( gmp_init( $input, $sourceBase ), $destBase );
3239         } elseif( extension_loaded( 'bcmath' ) && ( $engine == 'auto' || $engine == 'bcmath' ) ) {
3240                 $decimal = '0';
3241                 foreach( str_split( strtolower( $input ) ) as $char ) {
3242                         $decimal = bcmul( $decimal, $sourceBase );
3243                         $decimal = bcadd( $decimal, $baseChars[$char] );
3244                 }
3245
3246                 for( $result = ''; bccomp( $decimal, 0 ); $decimal = bcdiv( $decimal, $destBase, 0 ) ) {
3247                         $result .= $baseChars[bcmod( $decimal, $destBase )];
3248                 }
3249
3250                 $result = strrev( $result );
3251         } else {
3252                 $inDigits = array();
3253                 foreach( str_split( strtolower( $input ) ) as $char ) {
3254                         $inDigits[] = $baseChars[$char];
3255                 }
3256
3257                 // Iterate over the input, modulo-ing out an output digit
3258                 // at a time until input is gone.
3259                 $result = '';
3260                 while( $inDigits ) {
3261                         $work = 0;
3262                         $workDigits = array();
3263
3264                         // Long division...
3265                         foreach( $inDigits as $digit ) {
3266                                 $work *= $sourceBase;
3267                                 $work += $digit;
3268
3269                                 if( $workDigits || $work >= $destBase ) {
3270                                         $workDigits[] = (int) ( $work / $destBase );
3271                                 }
3272                                 $work %= $destBase;
3273                         }
3274
3275                         // All that division leaves us with a remainder,
3276                         // which is conveniently our next output digit.
3277                         $result .= $baseChars[$work];
3278
3279                         // And we continue!
3280                         $inDigits = $workDigits;
3281                 }
3282
3283                 $result = strrev( $result );
3284         }
3285
3286         if( !$lowercase ) {
3287                 $result = strtoupper( $result );
3288         }
3289
3290         return str_pad( $result, $pad, '0', STR_PAD_LEFT );
3291 }
3292
3293 /**
3294  * Create an object with a given name and an array of construct parameters
3295  *
3296  * @param $name String
3297  * @param $p Array: parameters
3298  * @return object
3299  * @deprecated since 1.18, warnings in 1.18, removal in 1.20
3300  */
3301 function wfCreateObject( $name, $p ) {
3302         wfDeprecated( __FUNCTION__, '1.18' );
3303         return MWFunction::newObj( $name, $p );
3304 }
3305
3306 /**
3307  * @return bool
3308  */
3309 function wfHttpOnlySafe() {
3310         global $wgHttpOnlyBlacklist;
3311
3312         if( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
3313                 foreach( $wgHttpOnlyBlacklist as $regex ) {
3314                         if( preg_match( $regex, $_SERVER['HTTP_USER_AGENT'] ) ) {
3315                                 return false;
3316                         }
3317                 }
3318         }
3319
3320         return true;
3321 }
3322
3323 /**
3324  * Check if there is sufficent entropy in php's built-in session generation
3325  * @return bool true = there is sufficient entropy
3326  */
3327 function wfCheckEntropy() {
3328         return (
3329                         ( wfIsWindows() && version_compare( PHP_VERSION, '5.3.3', '>=' ) )
3330                         || ini_get( 'session.entropy_file' )
3331                 )
3332                 && intval( ini_get( 'session.entropy_length' ) ) >= 32;
3333 }
3334
3335 /**
3336  * Override session_id before session startup if php's built-in
3337  * session generation code is not secure.
3338  */
3339 function wfFixSessionID() {
3340         // If the cookie or session id is already set we already have a session and should abort
3341         if ( isset( $_COOKIE[ session_name() ] ) || session_id() ) {
3342                 return;
3343         }
3344
3345         // PHP's built-in session entropy is enabled if:
3346         // - entropy_file is set or you're on Windows with php 5.3.3+
3347         // - AND entropy_length is > 0
3348         // We treat it as disabled if it doesn't have an entropy length of at least 32
3349         $entropyEnabled = wfCheckEntropy();
3350
3351         // If built-in entropy is not enabled or not sufficient override php's built in session id generation code
3352         if ( !$entropyEnabled ) {
3353                 wfDebug( __METHOD__ . ": PHP's built in entropy is disabled or not sufficient, overriding session id generation using our cryptrand source.\n" );
3354                 session_id( MWCryptRand::generateHex( 32 ) );
3355         }
3356 }
3357
3358 /**
3359  * Initialise php session
3360  *
3361  * @param $sessionId Bool
3362  */
3363 function wfSetupSession( $sessionId = false ) {
3364         global $wgSessionsInMemcached, $wgSessionsInObjectCache, $wgCookiePath, $wgCookieDomain,
3365                         $wgCookieSecure, $wgCookieHttpOnly, $wgSessionHandler;
3366         if( $wgSessionsInObjectCache || $wgSessionsInMemcached ) {
3367                 ObjectCacheSessionHandler::install();
3368         } elseif( $wgSessionHandler && $wgSessionHandler != ini_get( 'session.save_handler' ) ) {
3369                 # Only set this if $wgSessionHandler isn't null and session.save_handler
3370                 # hasn't already been set to the desired value (that causes errors)
3371                 ini_set( 'session.save_handler', $wgSessionHandler );
3372         }
3373         $httpOnlySafe = wfHttpOnlySafe() && $wgCookieHttpOnly;
3374         wfDebugLog( 'cookie',
3375                 'session_set_cookie_params: "' . implode( '", "',
3376                         array(
3377                                 0,
3378                                 $wgCookiePath,
3379                                 $wgCookieDomain,
3380                                 $wgCookieSecure,
3381                                 $httpOnlySafe ) ) . '"' );
3382         session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $httpOnlySafe );
3383         session_cache_limiter( 'private, must-revalidate' );
3384         if ( $sessionId ) {
3385                 session_id( $sessionId );
3386         } else {
3387                 wfFixSessionID();
3388         }
3389         wfSuppressWarnings();
3390         session_start();
3391         wfRestoreWarnings();
3392 }
3393
3394 /**
3395  * Get an object from the precompiled serialized directory
3396  *
3397  * @param $name String
3398  * @return Mixed: the variable on success, false on failure
3399  */
3400 function wfGetPrecompiledData( $name ) {
3401         global $IP;
3402
3403         $file = "$IP/serialized/$name";
3404         if ( file_exists( $file ) ) {
3405                 $blob = file_get_contents( $file );
3406                 if ( $blob ) {
3407                         return unserialize( $blob );
3408                 }
3409         }
3410         return false;
3411 }
3412
3413 /**
3414  * Get a cache key
3415  *
3416  * @param varargs
3417  * @return String
3418  */
3419 function wfMemcKey( /*... */ ) {
3420         global $wgCachePrefix;
3421         $prefix = $wgCachePrefix === false ? wfWikiID() : $wgCachePrefix;
3422         $args = func_get_args();
3423         $key = $prefix . ':' . implode( ':', $args );
3424         $key = str_replace( ' ', '_', $key );
3425         return $key;
3426 }
3427
3428 /**
3429  * Get a cache key for a foreign DB
3430  *
3431  * @param $db String
3432  * @param $prefix String
3433  * @param varargs String
3434  * @return String
3435  */
3436 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
3437         $args = array_slice( func_get_args(), 2 );
3438         if ( $prefix ) {
3439                 $key = "$db-$prefix:" . implode( ':', $args );
3440         } else {
3441                 $key = $db . ':' . implode( ':', $args );
3442         }
3443         return $key;
3444 }
3445
3446 /**
3447  * Get an ASCII string identifying this wiki
3448  * This is used as a prefix in memcached keys
3449  *
3450  * @return String
3451  */
3452 function wfWikiID() {
3453         global $wgDBprefix, $wgDBname;
3454         if ( $wgDBprefix ) {
3455                 return "$wgDBname-$wgDBprefix";
3456         } else {
3457                 return $wgDBname;
3458         }
3459 }
3460
3461 /**
3462  * Split a wiki ID into DB name and table prefix
3463  *
3464  * @param $wiki String
3465  *
3466  * @return array
3467  */
3468 function wfSplitWikiID( $wiki ) {
3469         $bits = explode( '-', $wiki, 2 );
3470         if ( count( $bits ) < 2 ) {
3471                 $bits[] = '';
3472         }
3473         return $bits;
3474 }
3475
3476 /**
3477  * Get a Database object.
3478  *
3479  * @param $db Integer: index of the connection to get. May be DB_MASTER for the
3480  *            master (for write queries), DB_SLAVE for potentially lagged read
3481  *            queries, or an integer >= 0 for a particular server.
3482  *
3483  * @param $groups Mixed: query groups. An array of group names that this query
3484  *                belongs to. May contain a single string if the query is only
3485  *                in one group.
3486  *
3487  * @param $wiki String: the wiki ID, or false for the current wiki
3488  *
3489  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
3490  * will always return the same object, unless the underlying connection or load
3491  * balancer is manually destroyed.
3492  *
3493  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
3494  * updater to ensure that a proper database is being updated.
3495  *
3496  * @return DatabaseBase
3497  */
3498 function &wfGetDB( $db, $groups = array(), $wiki = false ) {
3499         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
3500 }
3501
3502 /**
3503  * Get a load balancer object.
3504  *
3505  * @param $wiki String: wiki ID, or false for the current wiki
3506  * @return LoadBalancer
3507  */
3508 function wfGetLB( $wiki = false ) {
3509         return wfGetLBFactory()->getMainLB( $wiki );
3510 }
3511
3512 /**
3513  * Get the load balancer factory object
3514  *
3515  * @return LBFactory
3516  */
3517 function &wfGetLBFactory() {
3518         return LBFactory::singleton();
3519 }
3520
3521 /**
3522  * Find a file.
3523  * Shortcut for RepoGroup::singleton()->findFile()
3524  *
3525  * @param $title String or Title object
3526  * @param $options array Associative array of options:
3527  *     time:           requested time for an archived image, or false for the
3528  *                     current version. An image object will be returned which was
3529  *                     created at the specified time.
3530  *
3531  *     ignoreRedirect: If true, do not follow file redirects
3532  *
3533  *     private:        If true, return restricted (deleted) files if the current
3534  *                     user is allowed to view them. Otherwise, such files will not
3535  *                     be found.
3536  *
3537  *     bypassCache:    If true, do not use the process-local cache of File objects
3538  *
3539  * @return File, or false if the file does not exist
3540  */
3541 function wfFindFile( $title, $options = array() ) {
3542         return RepoGroup::singleton()->findFile( $title, $options );
3543 }
3544
3545 /**
3546  * Get an object referring to a locally registered file.
3547  * Returns a valid placeholder object if the file does not exist.
3548  *
3549  * @param $title Title|String
3550  * @return LocalFile|null A File, or null if passed an invalid Title
3551  */
3552 function wfLocalFile( $title ) {
3553         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
3554 }
3555
3556 /**
3557  * Stream a file to the browser. Back-compat alias for StreamFile::stream()
3558  * @deprecated since 1.19
3559  */
3560 function wfStreamFile( $fname, $headers = array() ) {
3561         wfDeprecated( __FUNCTION__, '1.19' );
3562         StreamFile::stream( $fname, $headers );
3563 }
3564
3565 /**
3566  * Should low-performance queries be disabled?
3567  *
3568  * @return Boolean
3569  * @codeCoverageIgnore
3570  */
3571 function wfQueriesMustScale() {
3572         global $wgMiserMode;
3573         return $wgMiserMode
3574                 || ( SiteStats::pages() > 100000
3575                 && SiteStats::edits() > 1000000
3576                 && SiteStats::users() > 10000 );
3577 }
3578
3579 /**
3580  * Get the path to a specified script file, respecting file
3581  * extensions; this is a wrapper around $wgScriptExtension etc.
3582  * except for 'index' and 'load' which use $wgScript/$wgLoadScript
3583  *
3584  * @param $script String: script filename, sans extension
3585  * @return String
3586  */
3587 function wfScript( $script = 'index' ) {
3588         global $wgScriptPath, $wgScriptExtension, $wgScript, $wgLoadScript;
3589         if ( $script === 'index' ) {
3590                 return $wgScript;
3591         } else if ( $script === 'load' ) {
3592                 return $wgLoadScript;
3593         } else {
3594                 return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
3595         }
3596 }
3597
3598 /**
3599  * Get the script URL.
3600  *
3601  * @return string script URL
3602  */
3603 function wfGetScriptUrl() {
3604         if( isset( $_SERVER['SCRIPT_NAME'] ) ) {
3605                 #
3606                 # as it was called, minus the query string.
3607                 #
3608                 # Some sites use Apache rewrite rules to handle subdomains,
3609                 # and have PHP set up in a weird way that causes PHP_SELF
3610                 # to contain the rewritten URL instead of the one that the
3611                 # outside world sees.
3612                 #
3613                 # If in this mode, use SCRIPT_URL instead, which mod_rewrite
3614                 # provides containing the "before" URL.
3615                 return $_SERVER['SCRIPT_NAME'];
3616         } else {
3617                 return $_SERVER['URL'];
3618         }
3619 }
3620
3621 /**
3622  * Convenience function converts boolean values into "true"
3623  * or "false" (string) values
3624  *
3625  * @param $value Boolean
3626  * @return String
3627  */
3628 function wfBoolToStr( $value ) {
3629         return $value ? 'true' : 'false';
3630 }
3631
3632 /**
3633  * Get a platform-independent path to the null file, e.g. /dev/null
3634  *
3635  * @return string
3636  */
3637 function wfGetNull() {
3638         return wfIsWindows()
3639                 ? 'NUL'
3640                 : '/dev/null';
3641 }
3642
3643 /**
3644  * Modern version of wfWaitForSlaves(). Instead of looking at replication lag
3645  * and waiting for it to go down, this waits for the slaves to catch up to the
3646  * master position. Use this when updating very large numbers of rows, as
3647  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
3648  * a no-op if there are no slaves.
3649  *
3650  * @param $maxLag Integer (deprecated)
3651  * @param $wiki mixed Wiki identifier accepted by wfGetLB
3652  */
3653 function wfWaitForSlaves( $maxLag = false, $wiki = false ) {
3654         $lb = wfGetLB( $wiki );
3655         // bug 27975 - Don't try to wait for slaves if there are none
3656         // Prevents permission error when getting master position
3657         if ( $lb->getServerCount() > 1 ) {
3658                 $dbw = $lb->getConnection( DB_MASTER );
3659                 $pos = $dbw->getMasterPos();
3660                 $lb->waitForAll( $pos );
3661         }
3662 }
3663
3664 /**
3665  * Used to be used for outputting text in the installer/updater
3666  * @deprecated since 1.18, warnings in 1.18, remove in 1.20
3667  */
3668 function wfOut( $s ) {
3669         wfDeprecated( __FUNCTION__, '1.18' );
3670         global $wgCommandLineMode;
3671         if ( $wgCommandLineMode ) {
3672                 echo $s;
3673         } else {
3674                 echo htmlspecialchars( $s );
3675         }
3676         flush();
3677 }
3678
3679 /**
3680  * Count down from $n to zero on the terminal, with a one-second pause
3681  * between showing each number. For use in command-line scripts.
3682  * @codeCoverageIgnore
3683  * @param $n int
3684  */
3685 function wfCountDown( $n ) {
3686         for ( $i = $n; $i >= 0; $i-- ) {
3687                 if ( $i != $n ) {
3688                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3689                 }
3690                 echo $i;
3691                 flush();
3692                 if ( $i ) {
3693                         sleep( 1 );
3694                 }
3695         }
3696         echo "\n";
3697 }
3698
3699 /**
3700  * Generate a random 32-character hexadecimal token.
3701  * @param $salt Mixed: some sort of salt, if necessary, to add to random
3702  *              characters before hashing.
3703  * @return string
3704  * @codeCoverageIgnore
3705  * @deprecated since 1.20; Please use MWCryptRand for security purposes and wfRandomString for pesudo-random strings
3706  * @warning This method is NOT secure. Additionally it has many callers that use it for pesudo-random purposes.
3707  */
3708 function wfGenerateToken( $salt = '' ) {
3709         wfDeprecated( __METHOD__, '1.20' );
3710         $salt = serialize( $salt );
3711         return md5( mt_rand( 0, 0x7fffffff ) . $salt );
3712 }
3713
3714 /**
3715  * Replace all invalid characters with -
3716  * Additional characters can be defined in $wgIllegalFileChars (see bug 20489)
3717  * By default, $wgIllegalFileChars = ':'
3718  *
3719  * @param $name Mixed: filename to process
3720  * @return String
3721  */
3722 function wfStripIllegalFilenameChars( $name ) {
3723         global $wgIllegalFileChars;
3724         $illegalFileChars = $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '';
3725         $name = wfBaseName( $name );
3726         $name = preg_replace(
3727                 "/[^" . Title::legalChars() . "]" . $illegalFileChars . "/",
3728                 '-',
3729                 $name
3730         );
3731         return $name;
3732 }
3733
3734 /**
3735  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit;
3736  *
3737  * @return Integer value memory was set to.
3738  */
3739 function wfMemoryLimit() {
3740         global $wgMemoryLimit;
3741         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3742         if( $memlimit != -1 ) {
3743                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3744                 if( $conflimit == -1 ) {
3745                         wfDebug( "Removing PHP's memory limit\n" );
3746                         wfSuppressWarnings();
3747                         ini_set( 'memory_limit', $conflimit );
3748                         wfRestoreWarnings();
3749                         return $conflimit;
3750                 } elseif ( $conflimit > $memlimit ) {
3751                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3752                         wfSuppressWarnings();
3753                         ini_set( 'memory_limit', $conflimit );
3754                         wfRestoreWarnings();
3755                         return $conflimit;
3756                 }
3757         }
3758         return $memlimit;
3759 }
3760
3761 /**
3762  * Converts shorthand byte notation to integer form
3763  *
3764  * @param $string String
3765  * @return Integer
3766  */
3767 function wfShorthandToInteger( $string = '' ) {
3768         $string = trim( $string );
3769         if( $string === '' ) {
3770                 return -1;
3771         }
3772         $last = $string[strlen( $string ) - 1];
3773         $val = intval( $string );
3774         switch( $last ) {
3775                 case 'g':
3776                 case 'G':
3777                         $val *= 1024;
3778                         // break intentionally missing
3779                 case 'm':
3780                 case 'M':
3781                         $val *= 1024;
3782                         // break intentionally missing
3783                 case 'k':
3784                 case 'K':
3785                         $val *= 1024;
3786         }
3787
3788         return $val;
3789 }
3790
3791 /**
3792  * Get the normalised IETF language tag
3793  * See unit test for examples.
3794  *
3795  * @param $code String: The language code.
3796  * @return String: The language code which complying with BCP 47 standards.
3797  */
3798 function wfBCP47( $code ) {
3799         $codeSegment = explode( '-', $code );
3800         $codeBCP = array();
3801         foreach ( $codeSegment as $segNo => $seg ) {
3802                 if ( count( $codeSegment ) > 0 ) {
3803                         // when previous segment is x, it is a private segment and should be lc
3804                         if( $segNo > 0 && strtolower( $codeSegment[( $segNo - 1 )] ) == 'x' ) {
3805                                 $codeBCP[$segNo] = strtolower( $seg );
3806                         // ISO 3166 country code
3807                         } elseif ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3808                                 $codeBCP[$segNo] = strtoupper( $seg );
3809                         // ISO 15924 script code
3810                         } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3811                                 $codeBCP[$segNo] = ucfirst( strtolower( $seg ) );
3812                         // Use lowercase for other cases
3813                         } else {
3814                                 $codeBCP[$segNo] = strtolower( $seg );
3815                         }
3816                 } else {
3817                 // Use lowercase for single segment
3818                         $codeBCP[$segNo] = strtolower( $seg );
3819                 }
3820         }
3821         $langCode = implode( '-', $codeBCP );
3822         return $langCode;
3823 }
3824
3825 /**
3826  * Get a cache object.
3827  *
3828  * @param $inputType integer Cache type, one the the CACHE_* constants.
3829  * @return BagOStuff
3830  */
3831 function wfGetCache( $inputType ) {
3832         return ObjectCache::getInstance( $inputType );
3833 }
3834
3835 /**
3836  * Get the main cache object
3837  *
3838  * @return BagOStuff
3839  */
3840 function wfGetMainCache() {
3841         global $wgMainCacheType;
3842         return ObjectCache::getInstance( $wgMainCacheType );
3843 }
3844
3845 /**
3846  * Get the cache object used by the message cache
3847  *
3848  * @return BagOStuff
3849  */
3850 function wfGetMessageCacheStorage() {
3851         global $wgMessageCacheType;
3852         return ObjectCache::getInstance( $wgMessageCacheType );
3853 }
3854
3855 /**
3856  * Get the cache object used by the parser cache
3857  *
3858  * @return BagOStuff
3859  */
3860 function wfGetParserCacheStorage() {
3861         global $wgParserCacheType;
3862         return ObjectCache::getInstance( $wgParserCacheType );
3863 }
3864
3865 /**
3866  * Get the cache object used by the language converter
3867  *
3868  * @return BagOStuff
3869  */
3870 function wfGetLangConverterCacheStorage() {
3871         global $wgLanguageConverterCacheType;
3872         return ObjectCache::getInstance( $wgLanguageConverterCacheType );
3873 }
3874
3875 /**
3876  * Call hook functions defined in $wgHooks
3877  *
3878  * @param $event String: event name
3879  * @param $args Array: parameters passed to hook functions
3880  * @return Boolean True if no handler aborted the hook
3881  */
3882 function wfRunHooks( $event, $args = array() ) {
3883         return Hooks::run( $event, $args );
3884 }
3885
3886 /**
3887  * Wrapper around php's unpack.
3888  *
3889  * @param $format String: The format string (See php's docs)
3890  * @param $data: A binary string of binary data
3891  * @param $length integer or false: The minimun length of $data. This is to
3892  *      prevent reading beyond the end of $data. false to disable the check.
3893  *
3894  * Also be careful when using this function to read unsigned 32 bit integer
3895  * because php might make it negative.
3896  *
3897  * @throws MWException if $data not long enough, or if unpack fails
3898  * @return array Associative array of the extracted data
3899  */
3900 function wfUnpack( $format, $data, $length=false ) {
3901         if ( $length !== false ) {
3902                 $realLen = strlen( $data );
3903                 if ( $realLen < $length ) {
3904                         throw new MWException( "Tried to use wfUnpack on a "
3905                                 . "string of length $realLen, but needed one "
3906                                 . "of at least length $length."
3907                         );
3908                 }
3909         }
3910
3911         wfSuppressWarnings();
3912         $result = unpack( $format, $data );
3913         wfRestoreWarnings();
3914
3915         if ( $result === false ) {
3916                 // If it cannot extract the packed data.
3917                 throw new MWException( "unpack could not unpack binary data" );
3918         }
3919         return $result;
3920 }
3921
3922 /**
3923  * Determine if an image exists on the 'bad image list'.
3924  *
3925  * The format of MediaWiki:Bad_image_list is as follows:
3926  *    * Only list items (lines starting with "*") are considered
3927  *    * The first link on a line must be a link to a bad image
3928  *    * Any subsequent links on the same line are considered to be exceptions,
3929  *      i.e. articles where the image may occur inline.
3930  *
3931  * @param $name string the image name to check
3932  * @param $contextTitle Title|bool the page on which the image occurs, if known
3933  * @param $blacklist string wikitext of a file blacklist
3934  * @return bool
3935  */
3936 function wfIsBadImage( $name, $contextTitle = false, $blacklist = null ) {
3937         static $badImageCache = null; // based on bad_image_list msg
3938         wfProfileIn( __METHOD__ );
3939
3940         # Handle redirects
3941         $redirectTitle = RepoGroup::singleton()->checkRedirect( Title::makeTitle( NS_FILE, $name ) );
3942         if( $redirectTitle ) {
3943                 $name = $redirectTitle->getDbKey();
3944         }
3945
3946         # Run the extension hook
3947         $bad = false;
3948         if( !wfRunHooks( 'BadImage', array( $name, &$bad ) ) ) {
3949                 wfProfileOut( __METHOD__ );
3950                 return $bad;
3951         }
3952
3953         $cacheable = ( $blacklist === null );
3954         if( $cacheable && $badImageCache !== null ) {
3955                 $badImages = $badImageCache;
3956         } else { // cache miss
3957                 if ( $blacklist === null ) {
3958                         $blacklist = wfMessage( 'bad_image_list' )->inContentLanguage()->plain(); // site list
3959                 }
3960                 # Build the list now
3961                 $badImages = array();
3962                 $lines = explode( "\n", $blacklist );
3963                 foreach( $lines as $line ) {
3964                         # List items only
3965                         if ( substr( $line, 0, 1 ) !== '*' ) {
3966                                 continue;
3967                         }
3968
3969                         # Find all links
3970                         $m = array();
3971                         if ( !preg_match_all( '/\[\[:?(.*?)\]\]/', $line, $m ) ) {
3972                                 continue;
3973                         }
3974
3975                         $exceptions = array();
3976                         $imageDBkey = false;
3977                         foreach ( $m[1] as $i => $titleText ) {
3978                                 $title = Title::newFromText( $titleText );
3979                                 if ( !is_null( $title ) ) {
3980                                         if ( $i == 0 ) {
3981                                                 $imageDBkey = $title->getDBkey();
3982                                         } else {
3983                                                 $exceptions[$title->getPrefixedDBkey()] = true;
3984                                         }
3985                                 }
3986                         }
3987
3988                         if ( $imageDBkey !== false ) {
3989                                 $badImages[$imageDBkey] = $exceptions;
3990                         }
3991                 }
3992                 if ( $cacheable ) {
3993                         $badImageCache = $badImages;
3994                 }
3995         }
3996
3997         $contextKey = $contextTitle ? $contextTitle->getPrefixedDBkey() : false;
3998         $bad = isset( $badImages[$name] ) && !isset( $badImages[$name][$contextKey] );
3999         wfProfileOut( __METHOD__ );
4000         return $bad;
4001 }