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                 // bug 45069
 813                 if ( isset( $bits['path'] ) ) {
 814                         /* parse_url loses the third / for file:///c:/ urls (but not on variants) */
 815                         if ( substr( $bits['path'], 0, 1 ) !== '/' ) {
 816                                 $bits['path'] = '/' . $bits['path'];
 817                         }
 818                 } else {
 819                         $bits['path'] = '';
 820                 }
 821         }
 822
 823         // If the URL was protocol-relative, fix scheme and delimiter
 824         if ( $wasRelative ) {
 825                 $bits['scheme'] = '';
 826                 $bits['delimiter'] = '//';
 827         }
 828         return $bits;
 829 }
 830
 831 /**
 832  * Take a URL, make sure it's expanded to fully qualified, and replace any
 833  * encoded non-ASCII Unicode characters with their UTF-8 original forms
 834  * for more compact display and legibility for local audiences.
 835  *
 836  * @todo handle punycode domains too
 837  *
 838  * @param $url string
 839  * @return string
 840  */
 841 function wfExpandIRI( $url ) {
 842         return preg_replace_callback( '/((?:%[89A-F][0-9A-F])+)/i', 'wfExpandIRI_callback', wfExpandUrl( $url ) );
 843 }
 844
 845 /**
 846  * Private callback for wfExpandIRI
 847  * @param array $matches
 848  * @return string
 849  */
 850 function wfExpandIRI_callback( $matches ) {
 851         return urldecode( $matches[1] );
 852 }
 853
 854
 855
 856 /**
 857  * Make URL indexes, appropriate for the el_index field of externallinks.
 858  *
 859  * @param $url String
 860  * @return array
 861  */
 862 function wfMakeUrlIndexes( $url ) {
 863         $bits = wfParseUrl( $url );
 864
 865         // Reverse the labels in the hostname, convert to lower case
 866         // For emails reverse domainpart only
 867         if ( $bits['scheme'] == 'mailto' ) {
 868                 $mailparts = explode( '@', $bits['host'], 2 );
 869                 if ( count( $mailparts ) === 2 ) {
 870                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
 871                 } else {
 872                         // No domain specified, don't mangle it
 873                         $domainpart = '';
 874                 }
 875                 $reversedHost = $domainpart . '@' . $mailparts[0];
 876         } else {
 877                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
 878         }
 879         // Add an extra dot to the end
 880         // Why? Is it in wrong place in mailto links?
 881         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
 882                 $reversedHost .= '.';
 883         }
 884         // Reconstruct the pseudo-URL
 885         $prot = $bits['scheme'];
 886         $index = $prot . $bits['delimiter'] . $reversedHost;
 887         // Leave out user and password. Add the port, path, query and fragment
 888         if ( isset( $bits['port'] ) ) {
 889                 $index .= ':' . $bits['port'];
 890         }
 891         if ( isset( $bits['path'] ) ) {
 892                 $index .= $bits['path'];
 893         } else {
 894                 $index .= '/';
 895         }
 896         if ( isset( $bits['query'] ) ) {
 897                 $index .= '?' . $bits['query'];
 898         }
 899         if ( isset( $bits['fragment'] ) ) {
 900                 $index .= '#' . $bits['fragment'];
 901         }
 902
 903         if ( $prot == '' ) {
 904                 return array( "http:$index", "https:$index" );
 905         } else {
 906                 return array( $index );
 907         }
 908 }
 909
 910 /**
 911  * Check whether a given URL has a domain that occurs in a given set of domains
 912  * @param $url string URL
 913  * @param $domains array Array of domains (strings)
 914  * @return bool True if the host part of $url ends in one of the strings in $domains
 915  */
 916 function wfMatchesDomainList( $url, $domains ) {
 917         $bits = wfParseUrl( $url );
 918         if ( is_array( $bits ) && isset( $bits['host'] ) ) {
 919                 foreach ( (array)$domains as $domain ) {
 920                         // FIXME: This gives false positives. http://nds-nl.wikipedia.org will match nl.wikipedia.org
 921                         // We should use something that interprets dots instead
 922                         if ( substr( $bits['host'], -strlen( $domain ) ) === $domain ) {
 923                                 return true;
 924                         }
 925                 }
 926         }
 927         return false;
 928 }
 929
 930 /**
 931  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
 932  * In normal operation this is a NOP.
 933  *
 934  * Controlling globals:
 935  * $wgDebugLogFile - points to the log file
 936  * $wgProfileOnly - if set, normal debug messages will not be recorded.
 937  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
 938  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
 939  *
 940  * @param $text String
 941  * @param $logonly Bool: set true to avoid appearing in HTML when $wgDebugComments is set
 942  */
 943 function wfDebug( $text, $logonly = false ) {
 944         global $wgDebugLogFile, $wgProfileOnly, $wgDebugRawPage, $wgDebugLogPrefix;
 945
 946         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
 947                 return;
 948         }
 949
 950         $timer = wfDebugTimer();
 951         if ( $timer !== '' ) {
 952                 $text = preg_replace( '/[^\n]/', $timer . '\0', $text, 1 );
 953         }
 954
 955         if ( !$logonly ) {
 956                 MWDebug::debugMsg( $text );
 957         }
 958
 959         if ( wfRunHooks( 'Debug', array( $text, null /* no log group */ ) ) ) {
 960                 if ( $wgDebugLogFile != '' && !$wgProfileOnly ) {
 961                         # Strip unprintables; they can switch terminal modes when binary data
 962                         # gets dumped, which is pretty annoying.
 963                         $text = preg_replace( '![\x00-\x08\x0b\x0c\x0e-\x1f]!', ' ', $text );
 964                         $text = $wgDebugLogPrefix . $text;
 965                         wfErrorLog( $text, $wgDebugLogFile );
 966                 }
 967         }
 968 }
 969
 970 /**
 971  * Returns true if debug logging should be suppressed if $wgDebugRawPage = false
 972  * @return bool
 973  */
 974 function wfIsDebugRawPage() {
 975         static $cache;
 976         if ( $cache !== null ) {
 977                 return $cache;
 978         }
 979         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
 980         if ( ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' )
 981                 || (
 982                         isset( $_SERVER['SCRIPT_NAME'] )
 983                         && substr( $_SERVER['SCRIPT_NAME'], -8 ) == 'load.php'
 984                 ) )
 985         {
 986                 $cache = true;
 987         } else {
 988                 $cache = false;
 989         }
 990         return $cache;
 991 }
 992
 993 /**
 994  * Get microsecond timestamps for debug logs
 995  *
 996  * @return string
 997  */
 998 function wfDebugTimer() {
 999         global $wgDebugTimestamps, $wgRequestTime;
1000
1001         if ( !$wgDebugTimestamps ) {
1002                 return '';
1003         }
1004
1005         $prefix = sprintf( "%6.4f", microtime( true ) - $wgRequestTime );
1006         $mem = sprintf( "%5.1fM", ( memory_get_usage( true ) / ( 1024 * 1024 ) ) );
1007         return "$prefix $mem  ";
1008 }
1009
1010 /**
1011  * Send a line giving PHP memory usage.
1012  *
1013  * @param $exact Bool: print exact values instead of kilobytes (default: false)
1014  */
1015 function wfDebugMem( $exact = false ) {
1016         $mem = memory_get_usage();
1017         if( !$exact ) {
1018                 $mem = floor( $mem / 1024 ) . ' kilobytes';
1019         } else {
1020                 $mem .= ' bytes';
1021         }
1022         wfDebug( "Memory usage: $mem\n" );
1023 }
1024
1025 /**
1026  * Send a line to a supplementary debug log file, if configured, or main debug log if not.
1027  * $wgDebugLogGroups[$logGroup] should be set to a filename to send to a separate log.
1028  *
1029  * @param $logGroup String
1030  * @param $text String
1031  * @param $public Bool: whether to log the event in the public log if no private
1032  *                     log file is specified, (default true)
1033  */
1034 function wfDebugLog( $logGroup, $text, $public = true ) {
1035         global $wgDebugLogGroups;
1036         $text = trim( $text ) . "\n";
1037         if( isset( $wgDebugLogGroups[$logGroup] ) ) {
1038                 $time = wfTimestamp( TS_DB );
1039                 $wiki = wfWikiID();
1040                 $host = wfHostname();
1041                 if ( wfRunHooks( 'Debug', array( $text, $logGroup ) ) ) {
1042                         wfErrorLog( "$time $host $wiki: $text", $wgDebugLogGroups[$logGroup] );
1043                 }
1044         } elseif ( $public === true ) {
1045                 wfDebug( "[$logGroup] $text", true );
1046         }
1047 }
1048
1049 /**
1050  * Log for database errors
1051  *
1052  * @param $text String: database error message.
1053  */
1054 function wfLogDBError( $text ) {
1055         global $wgDBerrorLog, $wgDBerrorLogTZ;
1056         static $logDBErrorTimeZoneObject = null;
1057
1058         if ( $wgDBerrorLog ) {
1059                 $host = wfHostname();
1060                 $wiki = wfWikiID();
1061
1062                 if ( $wgDBerrorLogTZ && !$logDBErrorTimeZoneObject ) {
1063                         $logDBErrorTimeZoneObject = new DateTimeZone( $wgDBerrorLogTZ );
1064                 }
1065
1066                 // Workaround for https://bugs.php.net/bug.php?id=52063
1067                 // Can be removed when min PHP > 5.3.2
1068                 if ( $logDBErrorTimeZoneObject === null ) {
1069                         $d = date_create( "now" );
1070                 } else {
1071                         $d = date_create( "now", $logDBErrorTimeZoneObject );
1072                 }
1073
1074                 $date = $d->format( 'D M j G:i:s T Y' );
1075
1076                 $text = "$date\t$host\t$wiki\t$text";
1077                 wfErrorLog( $text, $wgDBerrorLog );
1078         }
1079 }
1080
1081 /**
1082  * Throws a warning that $function is deprecated
1083  *
1084  * @param $function String
1085  * @param $version String|bool: Version of MediaWiki that the function was deprecated in (Added in 1.19).
1086  * @param $component String|bool: Added in 1.19.
1087  * @param $callerOffset integer: How far up the callstack is the original
1088  *    caller. 2 = function that called the function that called
1089  *    wfDeprecated (Added in 1.20)
1090  *
1091  * @return null
1092  */
1093 function wfDeprecated( $function, $version = false, $component = false, $callerOffset = 2 ) {
1094         MWDebug::deprecated( $function, $version, $component, $callerOffset + 1 );
1095 }
1096
1097 /**
1098  * Send a warning either to the debug log or in a PHP error depending on
1099  * $wgDevelopmentWarnings
1100  *
1101  * @param $msg String: message to send
1102  * @param $callerOffset Integer: number of items to go back in the backtrace to
1103  *        find the correct caller (1 = function calling wfWarn, ...)
1104  * @param $level Integer: PHP error level; only used when $wgDevelopmentWarnings
1105  *        is true
1106  */
1107 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
1108         MWDebug::warning( $msg, $callerOffset + 1, $level );
1109 }
1110
1111 /**
1112  * Log to a file without getting "file size exceeded" signals.
1113  *
1114  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
1115  * send lines to the specified port, prefixed by the specified prefix and a space.
1116  *
1117  * @param $text String
1118  * @param $file String filename
1119  * @throws MWException
1120  */
1121 function wfErrorLog( $text, $file ) {
1122         if ( substr( $file, 0, 4 ) == 'udp:' ) {
1123                 # Needs the sockets extension
1124                 if ( preg_match( '!^(tcp|udp):(?://)?\[([0-9a-fA-F:]+)\]:(\d+)(?:/(.*))?$!', $file, $m ) ) {
1125                         // IPv6 bracketed host
1126                         $host = $m[2];
1127                         $port = intval( $m[3] );
1128                         $prefix = isset( $m[4] ) ? $m[4] : false;
1129                         $domain = AF_INET6;
1130                 } elseif ( preg_match( '!^(tcp|udp):(?://)?([a-zA-Z0-9.-]+):(\d+)(?:/(.*))?$!', $file, $m ) ) {
1131                         $host = $m[2];
1132                         if ( !IP::isIPv4( $host ) ) {
1133                                 $host = gethostbyname( $host );
1134                         }
1135                         $port = intval( $m[3] );
1136                         $prefix = isset( $m[4] ) ? $m[4] : false;
1137                         $domain = AF_INET;
1138                 } else {
1139                         throw new MWException( __METHOD__ . ': Invalid UDP specification' );
1140                 }
1141
1142                 // Clean it up for the multiplexer
1143                 if ( strval( $prefix ) !== '' ) {
1144                         $text = preg_replace( '/^/m', $prefix . ' ', $text );
1145
1146                         // Limit to 64KB
1147                         if ( strlen( $text ) > 65506 ) {
1148                                 $text = substr( $text, 0, 65506 );
1149                         }
1150
1151                         if ( substr( $text, -1 ) != "\n" ) {
1152                                 $text .= "\n";
1153                         }
1154                 } elseif ( strlen( $text ) > 65507 ) {
1155                         $text = substr( $text, 0, 65507 );
1156                 }
1157
1158                 $sock = socket_create( $domain, SOCK_DGRAM, SOL_UDP );
1159                 if ( !$sock ) {
1160                         return;
1161                 }
1162
1163                 socket_sendto( $sock, $text, strlen( $text ), 0, $host, $port );
1164                 socket_close( $sock );
1165         } else {
1166                 wfSuppressWarnings();
1167                 $exists = file_exists( $file );
1168                 $size = $exists ? filesize( $file ) : false;
1169                 if ( !$exists || ( $size !== false && $size + strlen( $text ) < 0x7fffffff ) ) {
1170                         file_put_contents( $file, $text, FILE_APPEND );
1171                 }
1172                 wfRestoreWarnings();
1173         }
1174 }
1175
1176 /**
1177  * @todo document
1178  */
1179 function wfLogProfilingData() {
1180         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
1181         global $wgProfileLimit, $wgUser;
1182
1183         $profiler = Profiler::instance();
1184
1185         # Profiling must actually be enabled...
1186         if ( $profiler->isStub() ) {
1187                 return;
1188         }
1189
1190         // Get total page request time and only show pages that longer than
1191         // $wgProfileLimit time (default is 0)
1192         $elapsed = microtime( true ) - $wgRequestTime;
1193         if ( $elapsed <= $wgProfileLimit ) {
1194                 return;
1195         }
1196
1197         $profiler->logData();
1198
1199         // Check whether this should be logged in the debug file.
1200         if ( $wgDebugLogFile == '' || ( !$wgDebugRawPage && wfIsDebugRawPage() ) ) {
1201                 return;
1202         }
1203
1204         $forward = '';
1205         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
1206                 $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
1207         }
1208         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
1209                 $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
1210         }
1211         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
1212                 $forward .= ' from ' . $_SERVER['HTTP_FROM'];
1213         }
1214         if ( $forward ) {
1215                 $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
1216         }
1217         // Don't load $wgUser at this late stage just for statistics purposes
1218         // @todo FIXME: We can detect some anons even if it is not loaded. See User::getId()
1219         if ( $wgUser->isItemLoaded( 'id' ) && $wgUser->isAnon() ) {
1220                 $forward .= ' anon';
1221         }
1222
1223         // Command line script uses a FauxRequest object which does not have
1224         // any knowledge about an URL and throw an exception instead.
1225         try {
1226                 $requestUrl = $wgRequest->getRequestURL();
1227         } catch ( MWException $e ) {
1228                 $requestUrl = 'n/a';
1229         }
1230
1231         $log = sprintf( "%s\t%04.3f\t%s\n",
1232                 gmdate( 'YmdHis' ), $elapsed,
1233                 urldecode( $requestUrl . $forward ) );
1234
1235         wfErrorLog( $log . $profiler->getOutput(), $wgDebugLogFile );
1236 }
1237
1238 /**
1239  * Increment a statistics counter
1240  *
1241  * @param $key String
1242  * @param $count Int
1243  * @return void
1244  */
1245 function wfIncrStats( $key, $count = 1 ) {
1246         global $wgStatsMethod;
1247
1248         $count = intval( $count );
1249         if ( $count == 0 ) {
1250                 return;
1251         }
1252
1253         if( $wgStatsMethod == 'udp' ) {
1254                 global $wgUDPProfilerHost, $wgUDPProfilerPort, $wgAggregateStatsID;
1255                 static $socket;
1256
1257                 $id = $wgAggregateStatsID !== false ? $wgAggregateStatsID : wfWikiID();
1258
1259                 if ( !$socket ) {
1260                         $socket = socket_create( AF_INET, SOCK_DGRAM, SOL_UDP );
1261                         $statline = "stats/{$id} - 1 1 1 1 1 -total\n";
1262                         socket_sendto(
1263                                 $socket,
1264                                 $statline,
1265                                 strlen( $statline ),
1266                                 0,
1267                                 $wgUDPProfilerHost,
1268                                 $wgUDPProfilerPort
1269                         );
1270                 }
1271                 $statline = "stats/{$id} - {$count} 1 1 1 1 {$key}\n";
1272                 wfSuppressWarnings();
1273                 socket_sendto(
1274                         $socket,
1275                         $statline,
1276                         strlen( $statline ),
1277                         0,
1278                         $wgUDPProfilerHost,
1279                         $wgUDPProfilerPort
1280                 );
1281                 wfRestoreWarnings();
1282         } elseif( $wgStatsMethod == 'cache' ) {
1283                 global $wgMemc;
1284                 $key = wfMemcKey( 'stats', $key );
1285                 if ( is_null( $wgMemc->incr( $key, $count ) ) ) {
1286                         $wgMemc->add( $key, $count );
1287                 }
1288         } else {
1289                 // Disabled
1290         }
1291 }
1292
1293 /**
1294  * Check if the wiki read-only lock file is present. This can be used to lock
1295  * off editing functions, but doesn't guarantee that the database will not be
1296  * modified.
1297  *
1298  * @return bool
1299  */
1300 function wfReadOnly() {
1301         global $wgReadOnlyFile, $wgReadOnly;
1302
1303         if ( !is_null( $wgReadOnly ) ) {
1304                 return (bool)$wgReadOnly;
1305         }
1306         if ( $wgReadOnlyFile == '' ) {
1307                 return false;
1308         }
1309         // Set $wgReadOnly for faster access next time
1310         if ( is_file( $wgReadOnlyFile ) ) {
1311                 $wgReadOnly = file_get_contents( $wgReadOnlyFile );
1312         } else {
1313                 $wgReadOnly = false;
1314         }
1315         return (bool)$wgReadOnly;
1316 }
1317
1318 /**
1319  * @return bool
1320  */
1321 function wfReadOnlyReason() {
1322         global $wgReadOnly;
1323         wfReadOnly();
1324         return $wgReadOnly;
1325 }
1326
1327 /**
1328  * Return a Language object from $langcode
1329  *
1330  * @param $langcode Mixed: either:
1331  *                  - a Language object
1332  *                  - code of the language to get the message for, if it is
1333  *                    a valid code create a language for that language, if
1334  *                    it is a string but not a valid code then make a basic
1335  *                    language object
1336  *                  - a boolean: if it's false then use the global object for
1337  *                    the current user's language (as a fallback for the old parameter
1338  *                    functionality), or if it is true then use global object
1339  *                    for the wiki's content language.
1340  * @return Language object
1341  */
1342 function wfGetLangObj( $langcode = false ) {
1343         # Identify which language to get or create a language object for.
1344         # Using is_object here due to Stub objects.
1345         if( is_object( $langcode ) ) {
1346                 # Great, we already have the object (hopefully)!
1347                 return $langcode;
1348         }
1349
1350         global $wgContLang, $wgLanguageCode;
1351         if( $langcode === true || $langcode === $wgLanguageCode ) {
1352                 # $langcode is the language code of the wikis content language object.
1353                 # or it is a boolean and value is true
1354                 return $wgContLang;
1355         }
1356
1357         global $wgLang;
1358         if( $langcode === false || $langcode === $wgLang->getCode() ) {
1359                 # $langcode is the language code of user language object.
1360                 # or it was a boolean and value is false
1361                 return $wgLang;
1362         }
1363
1364         $validCodes = array_keys( Language::fetchLanguageNames() );
1365         if( in_array( $langcode, $validCodes ) ) {
1366                 # $langcode corresponds to a valid language.
1367                 return Language::factory( $langcode );
1368         }
1369
1370         # $langcode is a string, but not a valid language code; use content language.
1371         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
1372         return $wgContLang;
1373 }
1374
1375 /**
1376  * Old function when $wgBetterDirectionality existed
1377  * All usage removed, wfUILang can be removed in near future
1378  *
1379  * @deprecated since 1.18
1380  * @return Language
1381  */
1382 function wfUILang() {
1383         wfDeprecated( __METHOD__, '1.18' );
1384         global $wgLang;
1385         return $wgLang;
1386 }
1387
1388 /**
1389  * This is the new function for getting translated interface messages.
1390  * See the Message class for documentation how to use them.
1391  * The intention is that this function replaces all old wfMsg* functions.
1392  * @param $key \string Message key.
1393  * Varargs: normal message parameters.
1394  * @return Message
1395  * @since 1.17
1396  */
1397 function wfMessage( $key /*...*/) {
1398         $params = func_get_args();
1399         array_shift( $params );
1400         if ( isset( $params[0] ) && is_array( $params[0] ) ) {
1401                 $params = $params[0];
1402         }
1403         return new Message( $key, $params );
1404 }
1405
1406 /**
1407  * This function accepts multiple message keys and returns a message instance
1408  * for the first message which is non-empty. If all messages are empty then an
1409  * instance of the first message key is returned.
1410  * @param varargs: message keys
1411  * @return Message
1412  * @since 1.18
1413  */
1414 function wfMessageFallback( /*...*/ ) {
1415         $args = func_get_args();
1416         return MWFunction::callArray( 'Message::newFallbackSequence', $args );
1417 }
1418
1419 /**
1420  * Get a message from anywhere, for the current user language.
1421  *
1422  * Use wfMsgForContent() instead if the message should NOT
1423  * change depending on the user preferences.
1424  *
1425  * @deprecated since 1.18
1426  *
1427  * @param $key String: lookup key for the message, usually
1428  *    defined in languages/Language.php
1429  *
1430  * Parameters to the message, which can be used to insert variable text into
1431  * it, can be passed to this function in the following formats:
1432  * - One per argument, starting at the second parameter
1433  * - As an array in the second parameter
1434  * These are not shown in the function definition.
1435  *
1436  * @return String
1437  */
1438 function wfMsg( $key ) {
1439         wfDeprecated( __METHOD__, '1.21' );
1440
1441         $args = func_get_args();
1442         array_shift( $args );
1443         return wfMsgReal( $key, $args );
1444 }
1445
1446 /**
1447  * Same as above except doesn't transform the message
1448  *
1449  * @deprecated since 1.18
1450  *
1451  * @param $key String
1452  * @return String
1453  */
1454 function wfMsgNoTrans( $key ) {
1455         wfDeprecated( __METHOD__, '1.21' );
1456
1457         $args = func_get_args();
1458         array_shift( $args );
1459         return wfMsgReal( $key, $args, true, false, false );
1460 }
1461
1462 /**
1463  * Get a message from anywhere, for the current global language
1464  * set with $wgLanguageCode.
1465  *
1466  * Use this if the message should NOT change dependent on the
1467  * language set in the user's preferences. This is the case for
1468  * most text written into logs, as well as link targets (such as
1469  * the name of the copyright policy page). Link titles, on the
1470  * other hand, should be shown in the UI language.
1471  *
1472  * Note that MediaWiki allows users to change the user interface
1473  * language in their preferences, but a single installation
1474  * typically only contains content in one language.
1475  *
1476  * Be wary of this distinction: If you use wfMsg() where you should
1477  * use wfMsgForContent(), a user of the software may have to
1478  * customize potentially hundreds of messages in
1479  * order to, e.g., fix a link in every possible language.
1480  *
1481  * @deprecated since 1.18
1482  *
1483  * @param $key String: lookup key for the message, usually
1484  *     defined in languages/Language.php
1485  * @return String
1486  */
1487 function wfMsgForContent( $key ) {
1488         wfDeprecated( __METHOD__, '1.21' );
1489
1490         global $wgForceUIMsgAsContentMsg;
1491         $args = func_get_args();
1492         array_shift( $args );
1493         $forcontent = true;
1494         if( is_array( $wgForceUIMsgAsContentMsg ) &&
1495                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
1496         {
1497                 $forcontent = false;
1498         }
1499         return wfMsgReal( $key, $args, true, $forcontent );
1500 }
1501
1502 /**
1503  * Same as above except doesn't transform the message
1504  *
1505  * @deprecated since 1.18
1506  *
1507  * @param $key String
1508  * @return String
1509  */
1510 function wfMsgForContentNoTrans( $key ) {
1511         wfDeprecated( __METHOD__, '1.21' );
1512
1513         global $wgForceUIMsgAsContentMsg;
1514         $args = func_get_args();
1515         array_shift( $args );
1516         $forcontent = true;
1517         if( is_array( $wgForceUIMsgAsContentMsg ) &&
1518                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
1519         {
1520                 $forcontent = false;
1521         }
1522         return wfMsgReal( $key, $args, true, $forcontent, false );
1523 }
1524
1525 /**
1526  * Really get a message
1527  *
1528  * @deprecated since 1.18
1529  *
1530  * @param $key String: key to get.
1531  * @param $args
1532  * @param $useDB Boolean
1533  * @param $forContent Mixed: Language code, or false for user lang, true for content lang.
1534  * @param $transform Boolean: Whether or not to transform the message.
1535  * @return String: the requested message.
1536  */
1537 function wfMsgReal( $key, $args, $useDB = true, $forContent = false, $transform = true ) {
1538         wfDeprecated( __METHOD__, '1.21' );
1539
1540         wfProfileIn( __METHOD__ );
1541         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
1542         $message = wfMsgReplaceArgs( $message, $args );
1543         wfProfileOut( __METHOD__ );
1544         return $message;
1545 }
1546
1547 /**
1548  * Fetch a message string value, but don't replace any keys yet.
1549  *
1550  * @deprecated since 1.18
1551  *
1552  * @param $key String
1553  * @param $useDB Bool
1554  * @param $langCode String: Code of the language to get the message for, or
1555  *                  behaves as a content language switch if it is a boolean.
1556  * @param $transform Boolean: whether to parse magic words, etc.
1557  * @return string
1558  */
1559 function wfMsgGetKey( $key, $useDB = true, $langCode = false, $transform = true ) {
1560         wfDeprecated( __METHOD__, '1.21' );
1561
1562         wfRunHooks( 'NormalizeMessageKey', array( &$key, &$useDB, &$langCode, &$transform ) );
1563
1564         $cache = MessageCache::singleton();
1565         $message = $cache->get( $key, $useDB, $langCode );
1566         if( $message === false ) {
1567                 $message = '&lt;' . htmlspecialchars( $key ) . '&gt;';
1568         } elseif ( $transform ) {
1569                 $message = $cache->transform( $message );
1570         }
1571         return $message;
1572 }
1573
1574 /**
1575  * Replace message parameter keys on the given formatted output.
1576  *
1577  * @param $message String
1578  * @param $args Array
1579  * @return string
1580  * @private
1581  */
1582 function wfMsgReplaceArgs( $message, $args ) {
1583         # Fix windows line-endings
1584         # Some messages are split with explode("\n", $msg)
1585         $message = str_replace( "\r", '', $message );
1586
1587         // Replace arguments
1588         if ( count( $args ) ) {
1589                 if ( is_array( $args[0] ) ) {
1590                         $args = array_values( $args[0] );
1591                 }
1592                 $replacementKeys = array();
1593                 foreach( $args as $n => $param ) {
1594                         $replacementKeys['$' . ( $n + 1 )] = $param;
1595                 }
1596                 $message = strtr( $message, $replacementKeys );
1597         }
1598
1599         return $message;
1600 }
1601
1602 /**
1603  * Return an HTML-escaped version of a message.
1604  * Parameter replacements, if any, are done *after* the HTML-escaping,
1605  * so parameters may contain HTML (eg links or form controls). Be sure
1606  * to pre-escape them if you really do want plaintext, or just wrap
1607  * the whole thing in htmlspecialchars().
1608  *
1609  * @deprecated since 1.18
1610  *
1611  * @param $key String
1612  * @param string ... parameters
1613  * @return string
1614  */
1615 function wfMsgHtml( $key ) {
1616         wfDeprecated( __METHOD__, '1.21' );
1617
1618         $args = func_get_args();
1619         array_shift( $args );
1620         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key ) ), $args );
1621 }
1622
1623 /**
1624  * Return an HTML version of message
1625  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
1626  * so parameters may contain HTML (eg links or form controls). Be sure
1627  * to pre-escape them if you really do want plaintext, or just wrap
1628  * the whole thing in htmlspecialchars().
1629  *
1630  * @deprecated since 1.18
1631  *
1632  * @param $key String
1633  * @param string ... parameters
1634  * @return string
1635  */
1636 function wfMsgWikiHtml( $key ) {
1637         wfDeprecated( __METHOD__, '1.21' );
1638
1639         $args = func_get_args();
1640         array_shift( $args );
1641         return wfMsgReplaceArgs(
1642                 MessageCache::singleton()->parse( wfMsgGetKey( $key ), null,
1643                 /* can't be set to false */ true, /* interface */ true )->getText(),
1644                 $args );
1645 }
1646
1647 /**
1648  * Returns message in the requested format
1649  *
1650  * @deprecated since 1.18
1651  *
1652  * @param $key String: key of the message
1653  * @param $options Array: processing rules. Can take the following options:
1654  *   <i>parse</i>: parses wikitext to HTML
1655  *   <i>parseinline</i>: parses wikitext to HTML and removes the surrounding
1656  *       p's added by parser or tidy
1657  *   <i>escape</i>: filters message through htmlspecialchars
1658  *   <i>escapenoentities</i>: same, but allows entity references like &#160; through
1659  *   <i>replaceafter</i>: parameters are substituted after parsing or escaping
1660  *   <i>parsemag</i>: transform the message using magic phrases
1661  *   <i>content</i>: fetch message for content language instead of interface
1662  * Also can accept a single associative argument, of the form 'language' => 'xx':
1663  *   <i>language</i>: Language object or language code to fetch message for
1664  *       (overriden by <i>content</i>).
1665  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
1666  *
1667  * @return String
1668  */
1669 function wfMsgExt( $key, $options ) {
1670         wfDeprecated( __METHOD__, '1.21' );
1671
1672         $args = func_get_args();
1673         array_shift( $args );
1674         array_shift( $args );
1675         $options = (array)$options;
1676
1677         foreach( $options as $arrayKey => $option ) {
1678                 if( !preg_match( '/^[0-9]+|language$/', $arrayKey ) ) {
1679                         # An unknown index, neither numeric nor "language"
1680                         wfWarn( "wfMsgExt called with incorrect parameter key $arrayKey", 1, E_USER_WARNING );
1681                 } elseif( preg_match( '/^[0-9]+$/', $arrayKey ) && !in_array( $option,
1682                 array( 'parse', 'parseinline', 'escape', 'escapenoentities',
1683                 'replaceafter', 'parsemag', 'content' ) ) ) {
1684                         # A numeric index with unknown value
1685                         wfWarn( "wfMsgExt called with incorrect parameter $option", 1, E_USER_WARNING );
1686                 }
1687         }
1688
1689         if( in_array( 'content', $options, true ) ) {
1690                 $forContent = true;
1691                 $langCode = true;
1692                 $langCodeObj = null;
1693         } elseif( array_key_exists( 'language', $options ) ) {
1694                 $forContent = false;
1695                 $langCode = wfGetLangObj( $options['language'] );
1696                 $langCodeObj = $langCode;
1697         } else {
1698                 $forContent = false;
1699                 $langCode = false;
1700                 $langCodeObj = null;
1701         }
1702
1703         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
1704
1705         if( !in_array( 'replaceafter', $options, true ) ) {
1706                 $string = wfMsgReplaceArgs( $string, $args );
1707         }
1708
1709         $messageCache = MessageCache::singleton();
1710         $parseInline = in_array( 'parseinline', $options, true );
1711         if( in_array( 'parse', $options, true ) || $parseInline ) {
1712                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj );
1713                 if ( $string instanceof ParserOutput ) {
1714                         $string = $string->getText();
1715                 }
1716
1717                 if ( $parseInline ) {
1718                         $m = array();
1719                         if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
1720                                 $string = $m[1];
1721                         }
1722                 }
1723         } elseif ( in_array( 'parsemag', $options, true ) ) {
1724                 $string = $messageCache->transform( $string,
1725                                 !$forContent, $langCodeObj );
1726         }
1727
1728         if ( in_array( 'escape', $options, true ) ) {
1729                 $string = htmlspecialchars ( $string );
1730         } elseif ( in_array( 'escapenoentities', $options, true ) ) {
1731                 $string = Sanitizer::escapeHtmlAllowEntities( $string );
1732         }
1733
1734         if( in_array( 'replaceafter', $options, true ) ) {
1735                 $string = wfMsgReplaceArgs( $string, $args );
1736         }
1737
1738         return $string;
1739 }
1740
1741 /**
1742  * Since wfMsg() and co suck, they don't return false if the message key they
1743  * looked up didn't exist but a XHTML string, this function checks for the
1744  * nonexistance of messages by checking the MessageCache::get() result directly.
1745  *
1746  * @deprecated since 1.18. Use Message::isDisabled().
1747  *
1748  * @param $key      String: the message key looked up
1749  * @return Boolean True if the message *doesn't* exist.
1750  */
1751 function wfEmptyMsg( $key ) {
1752         wfDeprecated( __METHOD__, '1.21' );
1753
1754         return MessageCache::singleton()->get( $key, /*useDB*/true, /*content*/false ) === false;
1755 }
1756
1757 /**
1758  * Throw a debugging exception. This function previously once exited the process,
1759  * but now throws an exception instead, with similar results.
1760  *
1761  * @param $msg String: message shown when dying.
1762  * @throws MWException
1763  */
1764 function wfDebugDieBacktrace( $msg = '' ) {
1765         throw new MWException( $msg );
1766 }
1767
1768 /**
1769  * Fetch server name for use in error reporting etc.
1770  * Use real server name if available, so we know which machine
1771  * in a server farm generated the current page.
1772  *
1773  * @return string
1774  */
1775 function wfHostname() {
1776         static $host;
1777         if ( is_null( $host ) ) {
1778
1779                 # Hostname overriding
1780                 global $wgOverrideHostname;
1781                 if( $wgOverrideHostname !== false ) {
1782                         # Set static and skip any detection
1783                         $host = $wgOverrideHostname;
1784                         return $host;
1785                 }
1786
1787                 if ( function_exists( 'posix_uname' ) ) {
1788                         // This function not present on Windows
1789                         $uname = posix_uname();
1790                 } else {
1791                         $uname = false;
1792                 }
1793                 if( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1794                         $host = $uname['nodename'];
1795                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1796                         # Windows computer name
1797                         $host = getenv( 'COMPUTERNAME' );
1798                 } else {
1799                         # This may be a virtual server.
1800                         $host = $_SERVER['SERVER_NAME'];
1801                 }
1802         }
1803         return $host;
1804 }
1805
1806 /**
1807  * Returns a HTML comment with the elapsed time since request.
1808  * This method has no side effects.
1809  *
1810  * @return string
1811  */
1812 function wfReportTime() {
1813         global $wgRequestTime, $wgShowHostnames;
1814
1815         $elapsed = microtime( true ) - $wgRequestTime;
1816
1817         return $wgShowHostnames
1818                 ? sprintf( '<!-- Served by %s in %01.3f secs. -->', wfHostname(), $elapsed )
1819                 : sprintf( '<!-- Served in %01.3f secs. -->', $elapsed );
1820 }
1821
1822 /**
1823  * Safety wrapper for debug_backtrace().
1824  *
1825  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
1826  * murky circumstances, which may be triggered in part by stub objects
1827  * or other fancy talkin'.
1828  *
1829  * Will return an empty array if Zend Optimizer is detected or if
1830  * debug_backtrace is disabled, otherwise the output from
1831  * debug_backtrace() (trimmed).
1832  *
1833  * @param $limit int This parameter can be used to limit the number of stack frames returned
1834  *
1835  * @return array of backtrace information
1836  */
1837 function wfDebugBacktrace( $limit = 0 ) {
1838         static $disabled = null;
1839
1840         if( extension_loaded( 'Zend Optimizer' ) ) {
1841                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
1842                 return array();
1843         }
1844
1845         if ( is_null( $disabled ) ) {
1846                 $disabled = false;
1847                 $functions = explode( ',', ini_get( 'disable_functions' ) );
1848                 $functions = array_map( 'trim', $functions );
1849                 $functions = array_map( 'strtolower', $functions );
1850                 if ( in_array( 'debug_backtrace', $functions ) ) {
1851                         wfDebug( "debug_backtrace is in disabled_functions\n" );
1852                         $disabled = true;
1853                 }
1854         }
1855         if ( $disabled ) {
1856                 return array();
1857         }
1858
1859         if ( $limit && version_compare( PHP_VERSION, '5.4.0', '>=' ) ) {
1860                 return array_slice( debug_backtrace( DEBUG_BACKTRACE_PROVIDE_OBJECT, $limit + 1 ), 1 );
1861         } else {
1862                 return array_slice( debug_backtrace(), 1 );
1863         }
1864 }
1865
1866 /**
1867  * Get a debug backtrace as a string
1868  *
1869  * @return string
1870  */
1871 function wfBacktrace() {
1872         global $wgCommandLineMode;
1873
1874         if ( $wgCommandLineMode ) {
1875                 $msg = '';
1876         } else {
1877                 $msg = "<ul>\n";
1878         }
1879         $backtrace = wfDebugBacktrace();
1880         foreach( $backtrace as $call ) {
1881                 if( isset( $call['file'] ) ) {
1882                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
1883                         $file = $f[count( $f ) - 1];
1884                 } else {
1885                         $file = '-';
1886                 }
1887                 if( isset( $call['line'] ) ) {
1888                         $line = $call['line'];
1889                 } else {
1890                         $line = '-';
1891                 }
1892                 if ( $wgCommandLineMode ) {
1893                         $msg .= "$file line $line calls ";
1894                 } else {
1895                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
1896                 }
1897                 if( !empty( $call['class'] ) ) {
1898                         $msg .= $call['class'] . $call['type'];
1899                 }
1900                 $msg .= $call['function'] . '()';
1901
1902                 if ( $wgCommandLineMode ) {
1903                         $msg .= "\n";
1904                 } else {
1905                         $msg .= "</li>\n";
1906                 }
1907         }
1908         if ( $wgCommandLineMode ) {
1909                 $msg .= "\n";
1910         } else {
1911                 $msg .= "</ul>\n";
1912         }
1913
1914         return $msg;
1915 }
1916
1917 /**
1918  * Get the name of the function which called this function
1919  * wfGetCaller( 1 ) is the function with the wfGetCaller() call (ie. __FUNCTION__)
1920  * wfGetCaller( 2 ) [default] is the caller of the function running wfGetCaller()
1921  * wfGetCaller( 3 ) is the parent of that.
1922  *
1923  * @param $level Int
1924  * @return string
1925  */
1926 function wfGetCaller( $level = 2 ) {
1927         $backtrace = wfDebugBacktrace( $level + 1 );
1928         if ( isset( $backtrace[$level] ) ) {
1929                 return wfFormatStackFrame( $backtrace[$level] );
1930         } else {
1931                 return 'unknown';
1932         }
1933 }
1934
1935 /**
1936  * Return a string consisting of callers in the stack. Useful sometimes
1937  * for profiling specific points.
1938  *
1939  * @param $limit int The maximum depth of the stack frame to return, or false for
1940  *               the entire stack.
1941  * @return String
1942  */
1943 function wfGetAllCallers( $limit = 3 ) {
1944         $trace = array_reverse( wfDebugBacktrace() );
1945         if ( !$limit || $limit > count( $trace ) - 1 ) {
1946                 $limit = count( $trace ) - 1;
1947         }
1948         $trace = array_slice( $trace, -$limit - 1, $limit );
1949         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1950 }
1951
1952 /**
1953  * Return a string representation of frame
1954  *
1955  * @param $frame Array
1956  * @return string
1957  */
1958 function wfFormatStackFrame( $frame ) {
1959         return isset( $frame['class'] ) ?
1960                 $frame['class'] . '::' . $frame['function'] :
1961                 $frame['function'];
1962 }
1963
1964
1965 /* Some generic result counters, pulled out of SearchEngine */
1966
1967
1968 /**
1969  * @todo document
1970  *
1971  * @param $offset Int
1972  * @param $limit Int
1973  * @return String
1974  */
1975 function wfShowingResults( $offset, $limit ) {
1976         return wfMessage( 'showingresults' )->numParams( $limit, $offset + 1 )->parse();
1977 }
1978
1979 /**
1980  * Generate (prev x| next x) (20|50|100...) type links for paging
1981  *
1982  * @param $offset String
1983  * @param $limit Integer
1984  * @param $link String
1985  * @param $query String: optional URL query parameter string
1986  * @param $atend Bool: optional param for specified if this is the last page
1987  * @return String
1988  * @deprecated in 1.19; use Language::viewPrevNext() instead
1989  */
1990 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
1991         wfDeprecated( __METHOD__, '1.19' );
1992
1993         global $wgLang;
1994
1995         $query = wfCgiToArray( $query );
1996
1997         if( is_object( $link ) ) {
1998                 $title = $link;
1999         } else {
2000                 $title = Title::newFromText( $link );
2001                 if( is_null( $title ) ) {
2002                         return false;
2003                 }
2004         }
2005
2006         return $wgLang->viewPrevNext( $title, $offset, $limit, $query, $atend );
2007 }
2008
2009 /**
2010  * Make a list item, used by various special pages
2011  *
2012  * @param $page String Page link
2013  * @param $details String Text between brackets
2014  * @param $oppositedm Boolean   Add the direction mark opposite to your
2015  *                                                              language, to display text properly
2016  * @return String
2017  * @deprecated since 1.19; use Language::specialList() instead
2018  */
2019 function wfSpecialList( $page, $details, $oppositedm = true ) {
2020         wfDeprecated( __METHOD__, '1.19' );
2021
2022         global $wgLang;
2023         return $wgLang->specialList( $page, $details, $oppositedm );
2024 }
2025
2026 /**
2027  * @todo document
2028  * @todo FIXME: We may want to blacklist some broken browsers
2029  *
2030  * @param $force Bool
2031  * @return bool Whereas client accept gzip compression
2032  */
2033 function wfClientAcceptsGzip( $force = false ) {
2034         static $result = null;
2035         if ( $result === null || $force ) {
2036                 $result = false;
2037                 if( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
2038                         # @todo FIXME: We may want to blacklist some broken browsers
2039                         $m = array();
2040                         if( preg_match(
2041                                 '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
2042                                 $_SERVER['HTTP_ACCEPT_ENCODING'],
2043                                 $m )
2044                         )
2045                         {
2046                                 if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
2047                                         $result = false;
2048                                         return $result;
2049                                 }
2050                                 wfDebug( "wfClientAcceptsGzip: client accepts gzip.\n" );
2051                                 $result = true;
2052                         }
2053                 }
2054         }
2055         return $result;
2056 }
2057
2058 /**
2059  * Obtain the offset and limit values from the request string;
2060  * used in special pages
2061  *
2062  * @param $deflimit Int default limit if none supplied
2063  * @param $optionname String Name of a user preference to check against
2064  * @return array
2065  *
2066  */
2067 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
2068         global $wgRequest;
2069         return $wgRequest->getLimitOffset( $deflimit, $optionname );
2070 }
2071
2072 /**
2073  * Escapes the given text so that it may be output using addWikiText()
2074  * without any linking, formatting, etc. making its way through. This
2075  * is achieved by substituting certain characters with HTML entities.
2076  * As required by the callers, "<nowiki>" is not used.
2077  *
2078  * @param $text String: text to be escaped
2079  * @return String
2080  */
2081 function wfEscapeWikiText( $text ) {
2082         $text = strtr( "\n$text", array(
2083                 '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
2084                 '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
2085                 '{' => '&#123;', '|' => '&#124;', '}' => '&#125;',
2086                 "\n#" => "\n&#35;", "\n*" => "\n&#42;",
2087                 "\n:" => "\n&#58;", "\n;" => "\n&#59;",
2088                 '://' => '&#58;//', 'ISBN ' => 'ISBN&#32;', 'RFC ' => 'RFC&#32;',
2089         ) );
2090         return substr( $text, 1 );
2091 }
2092
2093 /**
2094  * Get the current unix timetstamp with microseconds.  Useful for profiling
2095  * @return Float
2096  */
2097 function wfTime() {
2098         return microtime( true );
2099 }
2100
2101 /**
2102  * Sets dest to source and returns the original value of dest
2103  * If source is NULL, it just returns the value, it doesn't set the variable
2104  * If force is true, it will set the value even if source is NULL
2105  *
2106  * @param $dest Mixed
2107  * @param $source Mixed
2108  * @param $force Bool
2109  * @return Mixed
2110  */
2111 function wfSetVar( &$dest, $source, $force = false ) {
2112         $temp = $dest;
2113         if ( !is_null( $source ) || $force ) {
2114                 $dest = $source;
2115         }
2116         return $temp;
2117 }
2118
2119 /**
2120  * As for wfSetVar except setting a bit
2121  *
2122  * @param $dest Int
2123  * @param $bit Int
2124  * @param $state Bool
2125  *
2126  * @return bool
2127  */
2128 function wfSetBit( &$dest, $bit, $state = true ) {
2129         $temp = (bool)( $dest & $bit );
2130         if ( !is_null( $state ) ) {
2131                 if ( $state ) {
2132                         $dest |= $bit;
2133                 } else {
2134                         $dest &= ~$bit;
2135                 }
2136         }
2137         return $temp;
2138 }
2139
2140 /**
2141  * A wrapper around the PHP function var_export().
2142  * Either print it or add it to the regular output ($wgOut).
2143  *
2144  * @param $var mixed A PHP variable to dump.
2145  */
2146 function wfVarDump( $var ) {
2147         global $wgOut;
2148         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
2149         if ( headers_sent() || !isset( $wgOut ) || !is_object( $wgOut ) ) {
2150                 print $s;
2151         } else {
2152                 $wgOut->addHTML( $s );
2153         }
2154 }
2155
2156 /**
2157  * Provide a simple HTTP error.
2158  *
2159  * @param $code Int|String
2160  * @param $label String
2161  * @param $desc String
2162  */
2163 function wfHttpError( $code, $label, $desc ) {
2164         global $wgOut;
2165         $wgOut->disable();
2166         header( "HTTP/1.0 $code $label" );
2167         header( "Status: $code $label" );
2168         $wgOut->sendCacheControl();
2169
2170         header( 'Content-type: text/html; charset=utf-8' );
2171         print "<!doctype html>" .
2172                 '<html><head><title>' .
2173                 htmlspecialchars( $label ) .
2174                 '</title></head><body><h1>' .
2175                 htmlspecialchars( $label ) .
2176                 '</h1><p>' .
2177                 nl2br( htmlspecialchars( $desc ) ) .
2178                 "</p></body></html>\n";
2179 }
2180
2181 /**
2182  * Clear away any user-level output buffers, discarding contents.
2183  *
2184  * Suitable for 'starting afresh', for instance when streaming
2185  * relatively large amounts of data without buffering, or wanting to
2186  * output image files without ob_gzhandler's compression.
2187  *
2188  * The optional $resetGzipEncoding parameter controls suppression of
2189  * the Content-Encoding header sent by ob_gzhandler; by default it
2190  * is left. See comments for wfClearOutputBuffers() for why it would
2191  * be used.
2192  *
2193  * Note that some PHP configuration options may add output buffer
2194  * layers which cannot be removed; these are left in place.
2195  *
2196  * @param $resetGzipEncoding Bool
2197  */
2198 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
2199         if( $resetGzipEncoding ) {
2200                 // Suppress Content-Encoding and Content-Length
2201                 // headers from 1.10+s wfOutputHandler
2202                 global $wgDisableOutputCompression;
2203                 $wgDisableOutputCompression = true;
2204         }
2205         while( $status = ob_get_status() ) {
2206                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
2207                         // Probably from zlib.output_compression or other
2208                         // PHP-internal setting which can't be removed.
2209                         //
2210                         // Give up, and hope the result doesn't break
2211                         // output behavior.
2212                         break;
2213                 }
2214                 if( !ob_end_clean() ) {
2215                         // Could not remove output buffer handler; abort now
2216                         // to avoid getting in some kind of infinite loop.
2217                         break;
2218                 }
2219                 if( $resetGzipEncoding ) {
2220                         if( $status['name'] == 'ob_gzhandler' ) {
2221                                 // Reset the 'Content-Encoding' field set by this handler
2222                                 // so we can start fresh.
2223                                 header_remove( 'Content-Encoding' );
2224                                 break;
2225                         }
2226                 }
2227         }
2228 }
2229
2230 /**
2231  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
2232  *
2233  * Clear away output buffers, but keep the Content-Encoding header
2234  * produced by ob_gzhandler, if any.
2235  *
2236  * This should be used for HTTP 304 responses, where you need to
2237  * preserve the Content-Encoding header of the real result, but
2238  * also need to suppress the output of ob_gzhandler to keep to spec
2239  * and avoid breaking Firefox in rare cases where the headers and
2240  * body are broken over two packets.
2241  */
2242 function wfClearOutputBuffers() {
2243         wfResetOutputBuffers( false );
2244 }
2245
2246 /**
2247  * Converts an Accept-* header into an array mapping string values to quality
2248  * factors
2249  *
2250  * @param $accept String
2251  * @param $def String default
2252  * @return Array
2253  */
2254 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
2255         # No arg means accept anything (per HTTP spec)
2256         if( !$accept ) {
2257                 return array( $def => 1.0 );
2258         }
2259
2260         $prefs = array();
2261
2262         $parts = explode( ',', $accept );
2263
2264         foreach( $parts as $part ) {
2265                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
2266                 $values = explode( ';', trim( $part ) );
2267                 $match = array();
2268                 if ( count( $values ) == 1 ) {
2269                         $prefs[$values[0]] = 1.0;
2270                 } elseif ( preg_match( '/q\s*=\s*(\d*\.\d+)/', $values[1], $match ) ) {
2271                         $prefs[$values[0]] = floatval( $match[1] );
2272                 }
2273         }
2274
2275         return $prefs;
2276 }
2277
2278 /**
2279  * Checks if a given MIME type matches any of the keys in the given
2280  * array. Basic wildcards are accepted in the array keys.
2281  *
2282  * Returns the matching MIME type (or wildcard) if a match, otherwise
2283  * NULL if no match.
2284  *
2285  * @param $type String
2286  * @param $avail Array
2287  * @return string
2288  * @private
2289  */
2290 function mimeTypeMatch( $type, $avail ) {
2291         if( array_key_exists( $type, $avail ) ) {
2292                 return $type;
2293         } else {
2294                 $parts = explode( '/', $type );
2295                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
2296                         return $parts[0] . '/*';
2297                 } elseif( array_key_exists( '*/*', $avail ) ) {
2298                         return '*/*';
2299                 } else {
2300                         return null;
2301                 }
2302         }
2303 }
2304
2305 /**
2306  * Returns the 'best' match between a client's requested internet media types
2307  * and the server's list of available types. Each list should be an associative
2308  * array of type to preference (preference is a float between 0.0 and 1.0).
2309  * Wildcards in the types are acceptable.
2310  *
2311  * @param $cprefs Array: client's acceptable type list
2312  * @param $sprefs Array: server's offered types
2313  * @return string
2314  *
2315  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
2316  * XXX: generalize to negotiate other stuff
2317  */
2318 function wfNegotiateType( $cprefs, $sprefs ) {
2319         $combine = array();
2320
2321         foreach( array_keys( $sprefs ) as $type ) {
2322                 $parts = explode( '/', $type );
2323                 if( $parts[1] != '*' ) {
2324                         $ckey = mimeTypeMatch( $type, $cprefs );
2325                         if( $ckey ) {
2326                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
2327                         }
2328                 }
2329         }
2330
2331         foreach( array_keys( $cprefs ) as $type ) {
2332                 $parts = explode( '/', $type );
2333                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
2334                         $skey = mimeTypeMatch( $type, $sprefs );
2335                         if( $skey ) {
2336                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
2337                         }
2338                 }
2339         }
2340
2341         $bestq = 0;
2342         $besttype = null;
2343
2344         foreach( array_keys( $combine ) as $type ) {
2345                 if( $combine[$type] > $bestq ) {
2346                         $besttype = $type;
2347                         $bestq = $combine[$type];
2348                 }
2349         }
2350
2351         return $besttype;
2352 }
2353
2354 /**
2355  * Reference-counted warning suppression
2356  *
2357  * @param $end Bool
2358  */
2359 function wfSuppressWarnings( $end = false ) {
2360         static $suppressCount = 0;
2361         static $originalLevel = false;
2362
2363         if ( $end ) {
2364                 if ( $suppressCount ) {
2365                         --$suppressCount;
2366                         if ( !$suppressCount ) {
2367                                 error_reporting( $originalLevel );
2368                         }
2369                 }
2370         } else {
2371                 if ( !$suppressCount ) {
2372                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE | E_USER_WARNING | E_USER_NOTICE | E_DEPRECATED | E_USER_DEPRECATED | E_STRICT ) );
2373                 }
2374                 ++$suppressCount;
2375         }
2376 }
2377
2378 /**
2379  * Restore error level to previous value
2380  */
2381 function wfRestoreWarnings() {
2382         wfSuppressWarnings( true );
2383 }
2384
2385 # Autodetect, convert and provide timestamps of various types
2386
2387 /**
2388  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
2389  */
2390 define( 'TS_UNIX', 0 );
2391
2392 /**
2393  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
2394  */
2395 define( 'TS_MW', 1 );
2396
2397 /**
2398  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
2399  */
2400 define( 'TS_DB', 2 );
2401
2402 /**
2403  * RFC 2822 format, for E-mail and HTTP headers
2404  */
2405 define( 'TS_RFC2822', 3 );
2406
2407 /**
2408  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
2409  *
2410  * This is used by Special:Export
2411  */
2412 define( 'TS_ISO_8601', 4 );
2413
2414 /**
2415  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
2416  *
2417  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
2418  *       DateTime tag and page 36 for the DateTimeOriginal and
2419  *       DateTimeDigitized tags.
2420  */
2421 define( 'TS_EXIF', 5 );
2422
2423 /**
2424  * Oracle format time.
2425  */
2426 define( 'TS_ORACLE', 6 );
2427
2428 /**
2429  * Postgres format time.
2430  */
2431 define( 'TS_POSTGRES', 7 );
2432
2433 /**
2434  * DB2 format time
2435  */
2436 define( 'TS_DB2', 8 );
2437
2438 /**
2439  * ISO 8601 basic format with no timezone: 19860209T200000Z.  This is used by ResourceLoader
2440  */
2441 define( 'TS_ISO_8601_BASIC', 9 );
2442
2443 /**
2444  * Get a timestamp string in one of various formats
2445  *
2446  * @param $outputtype Mixed: A timestamp in one of the supported formats, the
2447  *                    function will autodetect which format is supplied and act
2448  *                    accordingly.
2449  * @param $ts Mixed: optional timestamp to convert, default 0 for the current time
2450  * @return Mixed: String / false The same date in the format specified in $outputtype or false
2451  */
2452 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
2453         try {
2454                 $timestamp = new MWTimestamp( $ts );
2455                 return $timestamp->getTimestamp( $outputtype );
2456         } catch( TimestampException $e ) {
2457                 wfDebug( "wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n" );
2458                 return false;
2459         }
2460 }
2461
2462 /**
2463  * Return a formatted timestamp, or null if input is null.
2464  * For dealing with nullable timestamp columns in the database.
2465  *
2466  * @param $outputtype Integer
2467  * @param $ts String
2468  * @return String
2469  */
2470 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2471         if( is_null( $ts ) ) {
2472                 return null;
2473         } else {
2474                 return wfTimestamp( $outputtype, $ts );
2475         }
2476 }
2477
2478 /**
2479  * Convenience function; returns MediaWiki timestamp for the present time.
2480  *
2481  * @return string
2482  */
2483 function wfTimestampNow() {
2484         # return NOW
2485         return wfTimestamp( TS_MW, time() );
2486 }
2487
2488 /**
2489  * Check if the operating system is Windows
2490  *
2491  * @return Bool: true if it's Windows, False otherwise.
2492  */
2493 function wfIsWindows() {
2494         static $isWindows = null;
2495         if ( $isWindows === null ) {
2496                 $isWindows = substr( php_uname(), 0, 7 ) == 'Windows';
2497         }
2498         return $isWindows;
2499 }
2500
2501 /**
2502  * Check if we are running under HipHop
2503  *
2504  * @return Bool
2505  */
2506 function wfIsHipHop() {
2507         return function_exists( 'hphp_thread_set_warmup_enabled' );
2508 }
2509
2510 /**
2511  * Swap two variables
2512  *
2513  * @param $x Mixed
2514  * @param $y Mixed
2515  */
2516 function swap( &$x, &$y ) {
2517         $z = $x;
2518         $x = $y;
2519         $y = $z;
2520 }
2521
2522 /**
2523  * Tries to get the system directory for temporary files. First
2524  * $wgTmpDirectory is checked, and then the TMPDIR, TMP, and TEMP
2525  * environment variables are then checked in sequence, and if none are
2526  * set try sys_get_temp_dir().
2527  *
2528  * NOTE: When possible, use instead the tmpfile() function to create
2529  * temporary files to avoid race conditions on file creation, etc.
2530  *
2531  * @return String
2532  */
2533 function wfTempDir() {
2534         global $wgTmpDirectory;
2535
2536         if ( $wgTmpDirectory !== false ) {
2537                 return $wgTmpDirectory;
2538         }
2539
2540         $tmpDir = array_map( "getenv", array( 'TMPDIR', 'TMP', 'TEMP' ) );
2541
2542         foreach( $tmpDir as $tmp ) {
2543                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
2544                         return $tmp;
2545                 }
2546         }
2547         return sys_get_temp_dir();
2548 }
2549
2550 /**
2551  * Make directory, and make all parent directories if they don't exist
2552  *
2553  * @param $dir String: full path to directory to create
2554  * @param $mode Integer: chmod value to use, default is $wgDirectoryMode
2555  * @param $caller String: optional caller param for debugging.
2556  * @throws MWException
2557  * @return bool
2558  */
2559 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2560         global $wgDirectoryMode;
2561
2562         if ( FileBackend::isStoragePath( $dir ) ) { // sanity
2563                 throw new MWException( __FUNCTION__ . " given storage path '$dir'." );
2564         }
2565
2566         if ( !is_null( $caller ) ) {
2567                 wfDebug( "$caller: called wfMkdirParents($dir)\n" );
2568         }
2569
2570         if( strval( $dir ) === '' || file_exists( $dir ) ) {
2571                 return true;
2572         }
2573
2574         $dir = str_replace( array( '\\', '/' ), DIRECTORY_SEPARATOR, $dir );
2575
2576         if ( is_null( $mode ) ) {
2577                 $mode = $wgDirectoryMode;
2578         }
2579
2580         // Turn off the normal warning, we're doing our own below
2581         wfSuppressWarnings();
2582         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2583         wfRestoreWarnings();
2584
2585         if( !$ok ) {
2586                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2587                 trigger_error( sprintf( "%s: failed to mkdir \"%s\" mode 0%o", __FUNCTION__, $dir, $mode ),
2588                         E_USER_WARNING );
2589         }
2590         return $ok;
2591 }
2592
2593 /**
2594  * Remove a directory and all its content.
2595  * Does not hide error.
2596  */
2597 function wfRecursiveRemoveDir( $dir ) {
2598         wfDebug( __FUNCTION__ . "( $dir )\n" );
2599         // taken from http://de3.php.net/manual/en/function.rmdir.php#98622
2600         if ( is_dir( $dir ) ) {
2601                 $objects = scandir( $dir );
2602                 foreach ( $objects as $object ) {
2603                         if ( $object != "." && $object != ".." ) {
2604                                 if ( filetype( $dir . '/' . $object ) == "dir" ) {
2605                                         wfRecursiveRemoveDir( $dir . '/' . $object );
2606                                 } else {
2607                                         unlink( $dir . '/' . $object );
2608                                 }
2609                         }
2610                 }
2611                 reset( $objects );
2612                 rmdir( $dir );
2613         }
2614 }
2615
2616 /**
2617  * @param $nr Mixed: the number to format
2618  * @param $acc Integer: the number of digits after the decimal point, default 2
2619  * @param $round Boolean: whether or not to round the value, default true
2620  * @return float
2621  */
2622 function wfPercent( $nr, $acc = 2, $round = true ) {
2623         $ret = sprintf( "%.${acc}f", $nr );
2624         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2625 }
2626
2627 /**
2628  * Find out whether or not a mixed variable exists in a string
2629  *
2630  * @deprecated Just use str(i)pos
2631  * @param $needle String
2632  * @param $str String
2633  * @param $insensitive Boolean
2634  * @return Boolean
2635  */
2636 function in_string( $needle, $str, $insensitive = false ) {
2637         wfDeprecated( __METHOD__, '1.21' );
2638         $func = 'strpos';
2639         if( $insensitive ) $func = 'stripos';
2640
2641         return $func( $str, $needle ) !== false;
2642 }
2643
2644 /**
2645  * Safety wrapper around ini_get() for boolean settings.
2646  * The values returned from ini_get() are pre-normalized for settings
2647  * set via php.ini or php_flag/php_admin_flag... but *not*
2648  * for those set via php_value/php_admin_value.
2649  *
2650  * It's fairly common for people to use php_value instead of php_flag,
2651  * which can leave you with an 'off' setting giving a false positive
2652  * for code that just takes the ini_get() return value as a boolean.
2653  *
2654  * To make things extra interesting, setting via php_value accepts
2655  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2656  * Unrecognized values go false... again opposite PHP's own coercion
2657  * from string to bool.
2658  *
2659  * Luckily, 'properly' set settings will always come back as '0' or '1',
2660  * so we only have to worry about them and the 'improper' settings.
2661  *
2662  * I frickin' hate PHP... :P
2663  *
2664  * @param $setting String
2665  * @return Bool
2666  */
2667 function wfIniGetBool( $setting ) {
2668         $val = ini_get( $setting );
2669         // 'on' and 'true' can't have whitespace around them, but '1' can.
2670         return strtolower( $val ) == 'on'
2671                 || strtolower( $val ) == 'true'
2672                 || strtolower( $val ) == 'yes'
2673                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2674 }
2675
2676 /**
2677  * Wrapper function for PHP's dl(). This doesn't work in most situations from
2678  * PHP 5.3 onward, and is usually disabled in shared environments anyway.
2679  *
2680  * @param $extension String A PHP extension. The file suffix (.so or .dll)
2681  *                          should be omitted
2682  * @param $fileName String Name of the library, if not $extension.suffix
2683  * @return Bool - Whether or not the extension is loaded
2684  */
2685 function wfDl( $extension, $fileName = null ) {
2686         if( extension_loaded( $extension ) ) {
2687                 return true;
2688         }
2689
2690         $canDl = false;
2691         if( PHP_SAPI == 'cli' || PHP_SAPI == 'cgi' || PHP_SAPI == 'embed' ) {
2692                 $canDl = ( function_exists( 'dl' ) && is_callable( 'dl' )
2693                 && wfIniGetBool( 'enable_dl' ) && !wfIniGetBool( 'safe_mode' ) );
2694         }
2695
2696         if( $canDl ) {
2697                 $fileName = $fileName ? $fileName : $extension;
2698                 if( wfIsWindows() ) {
2699                         $fileName = 'php_' . $fileName;
2700                 }
2701                 wfSuppressWarnings();
2702                 dl( $fileName . '.' . PHP_SHLIB_SUFFIX );
2703                 wfRestoreWarnings();
2704         }
2705         return extension_loaded( $extension );
2706 }
2707
2708 /**
2709  * Windows-compatible version of escapeshellarg()
2710  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
2711  * function puts single quotes in regardless of OS.
2712  *
2713  * Also fixes the locale problems on Linux in PHP 5.2.6+ (bug backported to
2714  * earlier distro releases of PHP)
2715  *
2716  * @param varargs
2717  * @return String
2718  */
2719 function wfEscapeShellArg( ) {
2720         wfInitShellLocale();
2721
2722         $args = func_get_args();
2723         $first = true;
2724         $retVal = '';
2725         foreach ( $args as $arg ) {
2726                 if ( !$first ) {
2727                         $retVal .= ' ';
2728                 } else {
2729                         $first = false;
2730                 }
2731
2732                 if ( wfIsWindows() ) {
2733                         // Escaping for an MSVC-style command line parser and CMD.EXE
2734                         // Refs:
2735                         //  * http://web.archive.org/web/20020708081031/http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
2736                         //  * http://technet.microsoft.com/en-us/library/cc723564.aspx
2737                         //  * Bug #13518
2738                         //  * CR r63214
2739                         // Double the backslashes before any double quotes. Escape the double quotes.
2740                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
2741                         $arg = '';
2742                         $iteration = 0;
2743                         foreach ( $tokens as $token ) {
2744                                 if ( $iteration % 2 == 1 ) {
2745                                         // Delimiter, a double quote preceded by zero or more slashes
2746                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
2747                                 } elseif ( $iteration % 4 == 2 ) {
2748                                         // ^ in $token will be outside quotes, need to be escaped
2749                                         $arg .= str_replace( '^', '^^', $token );
2750                                 } else { // $iteration % 4 == 0
2751                                         // ^ in $token will appear inside double quotes, so leave as is
2752                                         $arg .= $token;
2753                                 }
2754                                 $iteration++;
2755                         }
2756                         // Double the backslashes before the end of the string, because
2757                         // we will soon add a quote
2758                         $m = array();
2759                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
2760                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
2761                         }
2762
2763                         // Add surrounding quotes
2764                         $retVal .= '"' . $arg . '"';
2765                 } else {
2766                         $retVal .= escapeshellarg( $arg );
2767                 }
2768         }
2769         return $retVal;
2770 }
2771
2772 /**
2773  * Execute a shell command, with time and memory limits mirrored from the PHP
2774  * configuration if supported.
2775  * @param $cmd String Command line, properly escaped for shell.
2776  * @param &$retval null|Mixed optional, will receive the program's exit code.
2777  *                 (non-zero is usually failure)
2778  * @param $environ Array optional environment variables which should be
2779  *                 added to the executed command environment.
2780  * @param $limits Array optional array with limits(filesize, memory, time, walltime)
2781  *                 this overwrites the global wgShellMax* limits.
2782  * @return string collected stdout as a string (trailing newlines stripped)
2783  */
2784 function wfShellExec( $cmd, &$retval = null, $environ = array(), $limits = array() ) {
2785         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize, $wgMaxShellTime,
2786                 $wgMaxShellWallClockTime, $wgShellCgroup;
2787
2788         static $disabled;
2789         if ( is_null( $disabled ) ) {
2790                 $disabled = false;
2791                 if( wfIniGetBool( 'safe_mode' ) ) {
2792                         wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
2793                         $disabled = 'safemode';
2794                 } else {
2795                         $functions = explode( ',', ini_get( 'disable_functions' ) );
2796                         $functions = array_map( 'trim', $functions );
2797                         $functions = array_map( 'strtolower', $functions );
2798                         if ( in_array( 'passthru', $functions ) ) {
2799                                 wfDebug( "passthru is in disabled_functions\n" );
2800                                 $disabled = 'passthru';
2801                         }
2802                 }
2803         }
2804         if ( $disabled ) {
2805                 $retval = 1;
2806                 return $disabled == 'safemode' ?
2807                         'Unable to run external programs in safe mode.' :
2808                         'Unable to run external programs, passthru() is disabled.';
2809         }
2810
2811         wfInitShellLocale();
2812
2813         $envcmd = '';
2814         foreach( $environ as $k => $v ) {
2815                 if ( wfIsWindows() ) {
2816                         /* Surrounding a set in quotes (method used by wfEscapeShellArg) makes the quotes themselves
2817                          * appear in the environment variable, so we must use carat escaping as documented in
2818                          * http://technet.microsoft.com/en-us/library/cc723564.aspx
2819                          * Note however that the quote isn't listed there, but is needed, and the parentheses
2820                          * are listed there but doesn't appear to need it.
2821                          */
2822                         $envcmd .= "set $k=" . preg_replace( '/([&|()<>^"])/', '^\\1', $v ) . '&& ';
2823                 } else {
2824                         /* Assume this is a POSIX shell, thus required to accept variable assignments before the command
2825                          * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_09_01
2826                          */
2827                         $envcmd .= "$k=" . escapeshellarg( $v ) . ' ';
2828                 }
2829         }
2830         $cmd = $envcmd . $cmd;
2831
2832         if ( php_uname( 's' ) == 'Linux' ) {
2833                 $time = intval ( isset( $limits['time'] ) ? $limits['time'] : $wgMaxShellTime );
2834                 if ( isset( $limits['walltime'] ) ) {
2835                         $wallTime = intval( $limits['walltime'] );
2836                 } elseif ( isset( $limits['time'] ) ) {
2837                         $wallTime = $time;
2838                 } else {
2839                         $wallTime = intval( $wgMaxShellWallClockTime );
2840                 }
2841                 $mem = intval ( isset( $limits['memory'] ) ? $limits['memory'] : $wgMaxShellMemory );
2842                 $filesize = intval ( isset( $limits['filesize'] ) ? $limits['filesize'] : $wgMaxShellFileSize );
2843
2844                 if ( $time > 0 || $mem > 0 || $filesize > 0 || $wallTime > 0 ) {
2845                         $cmd = '/bin/bash ' . escapeshellarg( "$IP/includes/limit.sh" ) . ' ' .
2846                                 escapeshellarg( $cmd ) . ' ' .
2847                                 escapeshellarg(
2848                                         "MW_CPU_LIMIT=$time; " .
2849                                         'MW_CGROUP=' . escapeshellarg( $wgShellCgroup ) . '; ' .
2850                                         "MW_MEM_LIMIT=$mem; " .
2851                                         "MW_FILE_SIZE_LIMIT=$filesize; " .
2852                                         "MW_WALL_CLOCK_LIMIT=$wallTime"
2853                                 );
2854                 }
2855         }
2856         wfDebug( "wfShellExec: $cmd\n" );
2857
2858         $retval = 1; // error by default?
2859         ob_start();
2860         passthru( $cmd, $retval );
2861         $output = ob_get_contents();
2862         ob_end_clean();
2863
2864         if ( $retval == 127 ) {
2865                 wfDebugLog( 'exec', "Possibly missing executable file: $cmd\n" );
2866         }
2867         return $output;
2868 }
2869
2870 /**
2871  * Workaround for http://bugs.php.net/bug.php?id=45132
2872  * escapeshellarg() destroys non-ASCII characters if LANG is not a UTF-8 locale
2873  */
2874 function wfInitShellLocale() {
2875         static $done = false;
2876         if ( $done ) {
2877                 return;
2878         }
2879         $done = true;
2880         global $wgShellLocale;
2881         if ( !wfIniGetBool( 'safe_mode' ) ) {
2882                 putenv( "LC_CTYPE=$wgShellLocale" );
2883                 setlocale( LC_CTYPE, $wgShellLocale );
2884         }
2885 }
2886
2887 /**
2888  * Alias to wfShellWikiCmd()
2889  * @see wfShellWikiCmd()
2890  */
2891 function wfShellMaintenanceCmd( $script, array $parameters = array(), array $options = array() ) {
2892         return wfShellWikiCmd( $script, $parameters, $options );
2893 }
2894
2895 /**
2896  * Generate a shell-escaped command line string to run a MediaWiki cli script.
2897  * Note that $parameters should be a flat array and an option with an argument
2898  * should consist of two consecutive items in the array (do not use "--option value").
2899  * @param $script string MediaWiki cli script path
2900  * @param $parameters Array Arguments and options to the script
2901  * @param $options Array Associative array of options:
2902  *              'php': The path to the php executable
2903  *              'wrapper': Path to a PHP wrapper to handle the maintenance script
2904  * @return Array
2905  */
2906 function wfShellWikiCmd( $script, array $parameters = array(), array $options = array() ) {
2907         global $wgPhpCli;
2908         // Give site config file a chance to run the script in a wrapper.
2909         // The caller may likely want to call wfBasename() on $script.
2910         wfRunHooks( 'wfShellWikiCmd', array( &$script, &$parameters, &$options ) );
2911         $cmd = isset( $options['php'] ) ? array( $options['php'] ) : array( $wgPhpCli );
2912         if ( isset( $options['wrapper'] ) ) {
2913                 $cmd[] = $options['wrapper'];
2914         }
2915         $cmd[] = $script;
2916         // Escape each parameter for shell
2917         return implode( " ", array_map( 'wfEscapeShellArg', array_merge( $cmd, $parameters ) ) );
2918 }
2919
2920 /**
2921  * wfMerge attempts to merge differences between three texts.
2922  * Returns true for a clean merge and false for failure or a conflict.
2923  *
2924  * @param $old String
2925  * @param $mine String
2926  * @param $yours String
2927  * @param $result String
2928  * @return Bool
2929  */
2930 function wfMerge( $old, $mine, $yours, &$result ) {
2931         global $wgDiff3;
2932
2933         # This check may also protect against code injection in
2934         # case of broken installations.
2935         wfSuppressWarnings();
2936         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
2937         wfRestoreWarnings();
2938
2939         if( !$haveDiff3 ) {
2940                 wfDebug( "diff3 not found\n" );
2941                 return false;
2942         }
2943
2944         # Make temporary files
2945         $td = wfTempDir();
2946         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
2947         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
2948         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
2949
2950         # NOTE: diff3 issues a warning to stderr if any of the files does not end with
2951         #       a newline character. To avoid this, we normalize the trailing whitespace before
2952         #       creating the diff.
2953
2954         fwrite( $oldtextFile, rtrim( $old ) . "\n" );
2955         fclose( $oldtextFile );
2956         fwrite( $mytextFile, rtrim( $mine ) . "\n" );
2957         fclose( $mytextFile );
2958         fwrite( $yourtextFile, rtrim( $yours ) . "\n" );
2959         fclose( $yourtextFile );
2960
2961         # Check for a conflict
2962         $cmd = wfEscapeShellArg( $wgDiff3 ) . ' -a --overlap-only ' .
2963                 wfEscapeShellArg( $mytextName ) . ' ' .
2964                 wfEscapeShellArg( $oldtextName ) . ' ' .
2965                 wfEscapeShellArg( $yourtextName );
2966         $handle = popen( $cmd, 'r' );
2967
2968         if( fgets( $handle, 1024 ) ) {
2969                 $conflict = true;
2970         } else {
2971                 $conflict = false;
2972         }
2973         pclose( $handle );
2974
2975         # Merge differences
2976         $cmd = wfEscapeShellArg( $wgDiff3 ) . ' -a -e --merge ' .
2977                 wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
2978         $handle = popen( $cmd, 'r' );
2979         $result = '';
2980         do {
2981                 $data = fread( $handle, 8192 );
2982                 if ( strlen( $data ) == 0 ) {
2983                         break;
2984                 }
2985                 $result .= $data;
2986         } while ( true );
2987         pclose( $handle );
2988         unlink( $mytextName );
2989         unlink( $oldtextName );
2990         unlink( $yourtextName );
2991
2992         if ( $result === '' && $old !== '' && !$conflict ) {
2993                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
2994                 $conflict = true;
2995         }
2996         return !$conflict;
2997 }
2998
2999 /**
3000  * Returns unified plain-text diff of two texts.
3001  * Useful for machine processing of diffs.
3002  *
3003  * @param $before String: the text before the changes.
3004  * @param $after String: the text after the changes.
3005  * @param $params String: command-line options for the diff command.
3006  * @return String: unified diff of $before and $after
3007  */
3008 function wfDiff( $before, $after, $params = '-u' ) {
3009         if ( $before == $after ) {
3010                 return '';
3011         }
3012
3013         global $wgDiff;
3014         wfSuppressWarnings();
3015         $haveDiff = $wgDiff && file_exists( $wgDiff );
3016         wfRestoreWarnings();
3017
3018         # This check may also protect against code injection in
3019         # case of broken installations.
3020         if( !$haveDiff ) {
3021                 wfDebug( "diff executable not found\n" );
3022                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
3023                 $format = new UnifiedDiffFormatter();
3024                 return $format->format( $diffs );
3025         }
3026
3027         # Make temporary files
3028         $td = wfTempDir();
3029         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
3030         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
3031
3032         fwrite( $oldtextFile, $before );
3033         fclose( $oldtextFile );
3034         fwrite( $newtextFile, $after );
3035         fclose( $newtextFile );
3036
3037         // Get the diff of the two files
3038         $cmd = "$wgDiff " . $params . ' ' . wfEscapeShellArg( $oldtextName, $newtextName );
3039
3040         $h = popen( $cmd, 'r' );
3041
3042         $diff = '';
3043
3044         do {
3045                 $data = fread( $h, 8192 );
3046                 if ( strlen( $data ) == 0 ) {
3047                         break;
3048                 }
3049                 $diff .= $data;
3050         } while ( true );
3051
3052         // Clean up
3053         pclose( $h );
3054         unlink( $oldtextName );
3055         unlink( $newtextName );
3056
3057         // Kill the --- and +++ lines. They're not useful.
3058         $diff_lines = explode( "\n", $diff );
3059         if ( strpos( $diff_lines[0], '---' ) === 0 ) {
3060                 unset( $diff_lines[0] );
3061         }
3062         if ( strpos( $diff_lines[1], '+++' ) === 0 ) {
3063                 unset( $diff_lines[1] );
3064         }
3065
3066         $diff = implode( "\n", $diff_lines );
3067
3068         return $diff;
3069 }
3070
3071 /**
3072  * This function works like "use VERSION" in Perl, the program will die with a
3073  * backtrace if the current version of PHP is less than the version provided
3074  *
3075  * This is useful for extensions which due to their nature are not kept in sync
3076  * with releases, and might depend on other versions of PHP than the main code
3077  *
3078  * Note: PHP might die due to parsing errors in some cases before it ever
3079  *       manages to call this function, such is life
3080  *
3081  * @see perldoc -f use
3082  *
3083  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
3084  *                 a float
3085  * @throws MWException
3086  */
3087 function wfUsePHP( $req_ver ) {
3088         $php_ver = PHP_VERSION;
3089
3090         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
3091                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
3092         }
3093 }
3094
3095 /**
3096  * This function works like "use VERSION" in Perl except it checks the version
3097  * of MediaWiki, the program will die with a backtrace if the current version
3098  * of MediaWiki is less than the version provided.
3099  *
3100  * This is useful for extensions which due to their nature are not kept in sync
3101  * with releases
3102  *
3103  * @see perldoc -f use
3104  *
3105  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
3106  *                 a float
3107  * @throws MWException
3108  */
3109 function wfUseMW( $req_ver ) {
3110         global $wgVersion;
3111
3112         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
3113                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
3114         }
3115 }
3116
3117 /**
3118  * Return the final portion of a pathname.
3119  * Reimplemented because PHP5's "basename()" is buggy with multibyte text.
3120  * http://bugs.php.net/bug.php?id=33898
3121  *
3122  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
3123  * We'll consider it so always, as we don't want '\s' in our Unix paths either.
3124  *
3125  * @param $path String
3126  * @param $suffix String: to remove if present
3127  * @return String
3128  */
3129 function wfBaseName( $path, $suffix = '' ) {
3130         $encSuffix = ( $suffix == '' )
3131                 ? ''
3132                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
3133         $matches = array();
3134         if( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
3135                 return $matches[1];
3136         } else {
3137                 return '';
3138         }
3139 }
3140
3141 /**
3142  * Generate a relative path name to the given file.
3143  * May explode on non-matching case-insensitive paths,
3144  * funky symlinks, etc.
3145  *
3146  * @param $path String: absolute destination path including target filename
3147  * @param $from String: Absolute source path, directory only
3148  * @return String
3149  */
3150 function wfRelativePath( $path, $from ) {
3151         // Normalize mixed input on Windows...
3152         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
3153         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
3154
3155         // Trim trailing slashes -- fix for drive root
3156         $path = rtrim( $path, DIRECTORY_SEPARATOR );
3157         $from = rtrim( $from, DIRECTORY_SEPARATOR );
3158
3159         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
3160         $against = explode( DIRECTORY_SEPARATOR, $from );
3161
3162         if( $pieces[0] !== $against[0] ) {
3163                 // Non-matching Windows drive letters?
3164                 // Return a full path.
3165                 return $path;
3166         }
3167
3168         // Trim off common prefix
3169         while( count( $pieces ) && count( $against )
3170                 && $pieces[0] == $against[0] ) {
3171                 array_shift( $pieces );
3172                 array_shift( $against );
3173         }
3174
3175         // relative dots to bump us to the parent
3176         while( count( $against ) ) {
3177                 array_unshift( $pieces, '..' );
3178                 array_shift( $against );
3179         }
3180
3181         array_push( $pieces, wfBaseName( $path ) );
3182
3183         return implode( DIRECTORY_SEPARATOR, $pieces );
3184 }
3185
3186 /**
3187  * Do any deferred updates and clear the list
3188  *
3189  * @deprecated since 1.19
3190  * @see DeferredUpdates::doUpdate()
3191  * @param $commit string
3192  */
3193 function wfDoUpdates( $commit = '' ) {
3194         wfDeprecated( __METHOD__, '1.19' );
3195         DeferredUpdates::doUpdates( $commit );
3196 }
3197
3198 /**
3199  * Convert an arbitrarily-long digit string from one numeric base
3200  * to another, optionally zero-padding to a minimum column width.
3201  *
3202  * Supports base 2 through 36; digit values 10-36 are represented
3203  * as lowercase letters a-z. Input is case-insensitive.
3204  *
3205  * @param string $input Input number
3206  * @param int $sourceBase Base of the input number
3207  * @param int $destBase Desired base of the output
3208  * @param int $pad Minimum number of digits in the output (pad with zeroes)
3209  * @param bool $lowercase Whether to output in lowercase or uppercase
3210  * @param string $engine Either "gmp", "bcmath", or "php"
3211  * @return string|bool The output number as a string, or false on error
3212  */
3213 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1, $lowercase = true, $engine = 'auto' ) {
3214         $input = (string)$input;
3215         if(
3216                 $sourceBase < 2 ||
3217                 $sourceBase > 36 ||
3218                 $destBase < 2 ||
3219                 $destBase > 36 ||
3220                 $sourceBase != (int) $sourceBase ||
3221                 $destBase != (int) $destBase ||
3222                 $pad != (int) $pad ||
3223                 !preg_match( "/^[" . substr( '0123456789abcdefghijklmnopqrstuvwxyz', 0, $sourceBase ) . "]+$/i", $input )
3224         ) {
3225                 return false;
3226         }
3227
3228         static $baseChars = array (
3229                 10 => 'a', 11 => 'b', 12 => 'c', 13 => 'd', 14 => 'e', 15 => 'f',
3230                 16 => 'g', 17 => 'h', 18 => 'i', 19 => 'j', 20 => 'k', 21 => 'l',
3231                 22 => 'm', 23 => 'n', 24 => 'o', 25 => 'p', 26 => 'q', 27 => 'r',
3232                 28 => 's', 29 => 't', 30 => 'u', 31 => 'v', 32 => 'w', 33 => 'x',
3233                 34 => 'y', 35 => 'z',
3234
3235                 '0' => 0,  '1' => 1,  '2' => 2,  '3' => 3,  '4' => 4,  '5' => 5,
3236                 '6' => 6,  '7' => 7,  '8' => 8,  '9' => 9,  'a' => 10, 'b' => 11,
3237                 'c' => 12, 'd' => 13, 'e' => 14, 'f' => 15, 'g' => 16, 'h' => 17,
3238                 'i' => 18, 'j' => 19, 'k' => 20, 'l' => 21, 'm' => 22, 'n' => 23,
3239                 'o' => 24, 'p' => 25, 'q' => 26, 'r' => 27, 's' => 28, 't' => 29,
3240                 'u' => 30, 'v' => 31, 'w' => 32, 'x' => 33, 'y' => 34, 'z' => 35
3241         );
3242
3243         if( extension_loaded( 'gmp' ) && ( $engine == 'auto' || $engine == 'gmp' ) ) {
3244                 $result = gmp_strval( gmp_init( $input, $sourceBase ), $destBase );
3245         } elseif( extension_loaded( 'bcmath' ) && ( $engine == 'auto' || $engine == 'bcmath' ) ) {
3246                 $decimal = '0';
3247                 foreach( str_split( strtolower( $input ) ) as $char ) {
3248                         $decimal = bcmul( $decimal, $sourceBase );
3249                         $decimal = bcadd( $decimal, $baseChars[$char] );
3250                 }
3251
3252                 for( $result = ''; bccomp( $decimal, 0 ); $decimal = bcdiv( $decimal, $destBase, 0 ) ) {
3253                         $result .= $baseChars[bcmod( $decimal, $destBase )];
3254                 }
3255
3256                 $result = strrev( $result );
3257         } else {
3258                 $inDigits = array();
3259                 foreach( str_split( strtolower( $input ) ) as $char ) {
3260                         $inDigits[] = $baseChars[$char];
3261                 }
3262
3263                 // Iterate over the input, modulo-ing out an output digit
3264                 // at a time until input is gone.
3265                 $result = '';
3266                 while( $inDigits ) {
3267                         $work = 0;
3268                         $workDigits = array();
3269
3270                         // Long division...
3271                         foreach( $inDigits as $digit ) {
3272                                 $work *= $sourceBase;
3273                                 $work += $digit;
3274
3275                                 if( $workDigits || $work >= $destBase ) {
3276                                         $workDigits[] = (int) ( $work / $destBase );
3277                                 }
3278                                 $work %= $destBase;
3279                         }
3280
3281                         // All that division leaves us with a remainder,
3282                         // which is conveniently our next output digit.
3283                         $result .= $baseChars[$work];
3284
3285                         // And we continue!
3286                         $inDigits = $workDigits;
3287                 }
3288
3289                 $result = strrev( $result );
3290         }
3291
3292         if( !$lowercase ) {
3293                 $result = strtoupper( $result );
3294         }
3295
3296         return str_pad( $result, $pad, '0', STR_PAD_LEFT );
3297 }
3298
3299 /**
3300  * Create an object with a given name and an array of construct parameters
3301  *
3302  * @param $name String
3303  * @param $p Array: parameters
3304  * @return object
3305  * @deprecated since 1.18, warnings in 1.18, removal in 1.20
3306  */
3307 function wfCreateObject( $name, $p ) {
3308         wfDeprecated( __FUNCTION__, '1.18' );
3309         return MWFunction::newObj( $name, $p );
3310 }
3311
3312 /**
3313  * @return bool
3314  */
3315 function wfHttpOnlySafe() {
3316         global $wgHttpOnlyBlacklist;
3317
3318         if( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
3319                 foreach( $wgHttpOnlyBlacklist as $regex ) {
3320                         if( preg_match( $regex, $_SERVER['HTTP_USER_AGENT'] ) ) {
3321                                 return false;
3322                         }
3323                 }
3324         }
3325
3326         return true;
3327 }
3328
3329 /**
3330  * Check if there is sufficent entropy in php's built-in session generation
3331  * @return bool true = there is sufficient entropy
3332  */
3333 function wfCheckEntropy() {
3334         return (
3335                         ( wfIsWindows() && version_compare( PHP_VERSION, '5.3.3', '>=' ) )
3336                         || ini_get( 'session.entropy_file' )
3337                 )
3338                 && intval( ini_get( 'session.entropy_length' ) ) >= 32;
3339 }
3340
3341 /**
3342  * Override session_id before session startup if php's built-in
3343  * session generation code is not secure.
3344  */
3345 function wfFixSessionID() {
3346         // If the cookie or session id is already set we already have a session and should abort
3347         if ( isset( $_COOKIE[ session_name() ] ) || session_id() ) {
3348                 return;
3349         }
3350
3351         // PHP's built-in session entropy is enabled if:
3352         // - entropy_file is set or you're on Windows with php 5.3.3+
3353         // - AND entropy_length is > 0
3354         // We treat it as disabled if it doesn't have an entropy length of at least 32
3355         $entropyEnabled = wfCheckEntropy();
3356
3357         // If built-in entropy is not enabled or not sufficient override php's built in session id generation code
3358         if ( !$entropyEnabled ) {
3359                 wfDebug( __METHOD__ . ": PHP's built in entropy is disabled or not sufficient, overriding session id generation using our cryptrand source.\n" );
3360                 session_id( MWCryptRand::generateHex( 32 ) );
3361         }
3362 }
3363
3364 /**
3365  * Initialise php session
3366  *
3367  * @param $sessionId Bool
3368  */
3369 function wfSetupSession( $sessionId = false ) {
3370         global $wgSessionsInMemcached, $wgSessionsInObjectCache, $wgCookiePath, $wgCookieDomain,
3371                         $wgCookieSecure, $wgCookieHttpOnly, $wgSessionHandler;
3372         if( $wgSessionsInObjectCache || $wgSessionsInMemcached ) {
3373                 ObjectCacheSessionHandler::install();
3374         } elseif( $wgSessionHandler && $wgSessionHandler != ini_get( 'session.save_handler' ) ) {
3375                 # Only set this if $wgSessionHandler isn't null and session.save_handler
3376                 # hasn't already been set to the desired value (that causes errors)
3377                 ini_set( 'session.save_handler', $wgSessionHandler );
3378         }
3379         $httpOnlySafe = wfHttpOnlySafe() && $wgCookieHttpOnly;
3380         wfDebugLog( 'cookie',
3381                 'session_set_cookie_params: "' . implode( '", "',
3382                         array(
3383                                 0,
3384                                 $wgCookiePath,
3385                                 $wgCookieDomain,
3386                                 $wgCookieSecure,
3387                                 $httpOnlySafe ) ) . '"' );
3388         session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $httpOnlySafe );
3389         session_cache_limiter( 'private, must-revalidate' );
3390         if ( $sessionId ) {
3391                 session_id( $sessionId );
3392         } else {
3393                 wfFixSessionID();
3394         }
3395         wfSuppressWarnings();
3396         session_start();
3397         wfRestoreWarnings();
3398 }
3399
3400 /**
3401  * Get an object from the precompiled serialized directory
3402  *
3403  * @param $name String
3404  * @return Mixed: the variable on success, false on failure
3405  */
3406 function wfGetPrecompiledData( $name ) {
3407         global $IP;
3408
3409         $file = "$IP/serialized/$name";
3410         if ( file_exists( $file ) ) {
3411                 $blob = file_get_contents( $file );
3412                 if ( $blob ) {
3413                         return unserialize( $blob );
3414                 }
3415         }
3416         return false;
3417 }
3418
3419 /**
3420  * Get a cache key
3421  *
3422  * @param varargs
3423  * @return String
3424  */
3425 function wfMemcKey( /*... */ ) {
3426         global $wgCachePrefix;
3427         $prefix = $wgCachePrefix === false ? wfWikiID() : $wgCachePrefix;
3428         $args = func_get_args();
3429         $key = $prefix . ':' . implode( ':', $args );
3430         $key = str_replace( ' ', '_', $key );
3431         return $key;
3432 }
3433
3434 /**
3435  * Get a cache key for a foreign DB
3436  *
3437  * @param $db String
3438  * @param $prefix String
3439  * @param varargs String
3440  * @return String
3441  */
3442 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
3443         $args = array_slice( func_get_args(), 2 );
3444         if ( $prefix ) {
3445                 $key = "$db-$prefix:" . implode( ':', $args );
3446         } else {
3447                 $key = $db . ':' . implode( ':', $args );
3448         }
3449         return $key;
3450 }
3451
3452 /**
3453  * Get an ASCII string identifying this wiki
3454  * This is used as a prefix in memcached keys
3455  *
3456  * @return String
3457  */
3458 function wfWikiID() {
3459         global $wgDBprefix, $wgDBname;
3460         if ( $wgDBprefix ) {
3461                 return "$wgDBname-$wgDBprefix";
3462         } else {
3463                 return $wgDBname;
3464         }
3465 }
3466
3467 /**
3468  * Split a wiki ID into DB name and table prefix
3469  *
3470  * @param $wiki String
3471  *
3472  * @return array
3473  */
3474 function wfSplitWikiID( $wiki ) {
3475         $bits = explode( '-', $wiki, 2 );
3476         if ( count( $bits ) < 2 ) {
3477                 $bits[] = '';
3478         }
3479         return $bits;
3480 }
3481
3482 /**
3483  * Get a Database object.
3484  *
3485  * @param $db Integer: index of the connection to get. May be DB_MASTER for the
3486  *            master (for write queries), DB_SLAVE for potentially lagged read
3487  *            queries, or an integer >= 0 for a particular server.
3488  *
3489  * @param $groups Mixed: query groups. An array of group names that this query
3490  *                belongs to. May contain a single string if the query is only
3491  *                in one group.
3492  *
3493  * @param $wiki String: the wiki ID, or false for the current wiki
3494  *
3495  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
3496  * will always return the same object, unless the underlying connection or load
3497  * balancer is manually destroyed.
3498  *
3499  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
3500  * updater to ensure that a proper database is being updated.
3501  *
3502  * @return DatabaseBase
3503  */
3504 function &wfGetDB( $db, $groups = array(), $wiki = false ) {
3505         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
3506 }
3507
3508 /**
3509  * Get a load balancer object.
3510  *
3511  * @param $wiki String: wiki ID, or false for the current wiki
3512  * @return LoadBalancer
3513  */
3514 function wfGetLB( $wiki = false ) {
3515         return wfGetLBFactory()->getMainLB( $wiki );
3516 }
3517
3518 /**
3519  * Get the load balancer factory object
3520  *
3521  * @return LBFactory
3522  */
3523 function &wfGetLBFactory() {
3524         return LBFactory::singleton();
3525 }
3526
3527 /**
3528  * Find a file.
3529  * Shortcut for RepoGroup::singleton()->findFile()
3530  *
3531  * @param $title String or Title object
3532  * @param $options array Associative array of options:
3533  *     time:           requested time for an archived image, or false for the
3534  *                     current version. An image object will be returned which was
3535  *                     created at the specified time.
3536  *
3537  *     ignoreRedirect: If true, do not follow file redirects
3538  *
3539  *     private:        If true, return restricted (deleted) files if the current
3540  *                     user is allowed to view them. Otherwise, such files will not
3541  *                     be found.
3542  *
3543  *     bypassCache:    If true, do not use the process-local cache of File objects
3544  *
3545  * @return File, or false if the file does not exist
3546  */
3547 function wfFindFile( $title, $options = array() ) {
3548         return RepoGroup::singleton()->findFile( $title, $options );
3549 }
3550
3551 /**
3552  * Get an object referring to a locally registered file.
3553  * Returns a valid placeholder object if the file does not exist.
3554  *
3555  * @param $title Title|String
3556  * @return LocalFile|null A File, or null if passed an invalid Title
3557  */
3558 function wfLocalFile( $title ) {
3559         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
3560 }
3561
3562 /**
3563  * Stream a file to the browser. Back-compat alias for StreamFile::stream()
3564  * @deprecated since 1.19
3565  */
3566 function wfStreamFile( $fname, $headers = array() ) {
3567         wfDeprecated( __FUNCTION__, '1.19' );
3568         StreamFile::stream( $fname, $headers );
3569 }
3570
3571 /**
3572  * Should low-performance queries be disabled?
3573  *
3574  * @return Boolean
3575  * @codeCoverageIgnore
3576  */
3577 function wfQueriesMustScale() {
3578         global $wgMiserMode;
3579         return $wgMiserMode
3580                 || ( SiteStats::pages() > 100000
3581                 && SiteStats::edits() > 1000000
3582                 && SiteStats::users() > 10000 );
3583 }
3584
3585 /**
3586  * Get the path to a specified script file, respecting file
3587  * extensions; this is a wrapper around $wgScriptExtension etc.
3588  * except for 'index' and 'load' which use $wgScript/$wgLoadScript
3589  *
3590  * @param $script String: script filename, sans extension
3591  * @return String
3592  */
3593 function wfScript( $script = 'index' ) {
3594         global $wgScriptPath, $wgScriptExtension, $wgScript, $wgLoadScript;
3595         if ( $script === 'index' ) {
3596                 return $wgScript;
3597         } else if ( $script === 'load' ) {
3598                 return $wgLoadScript;
3599         } else {
3600                 return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
3601         }
3602 }
3603
3604 /**
3605  * Get the script URL.
3606  *
3607  * @return string script URL
3608  */
3609 function wfGetScriptUrl() {
3610         if( isset( $_SERVER['SCRIPT_NAME'] ) ) {
3611                 #
3612                 # as it was called, minus the query string.
3613                 #
3614                 # Some sites use Apache rewrite rules to handle subdomains,
3615                 # and have PHP set up in a weird way that causes PHP_SELF
3616                 # to contain the rewritten URL instead of the one that the
3617                 # outside world sees.
3618                 #
3619                 # If in this mode, use SCRIPT_URL instead, which mod_rewrite
3620                 # provides containing the "before" URL.
3621                 return $_SERVER['SCRIPT_NAME'];
3622         } else {
3623                 return $_SERVER['URL'];
3624         }
3625 }
3626
3627 /**
3628  * Convenience function converts boolean values into "true"
3629  * or "false" (string) values
3630  *
3631  * @param $value Boolean
3632  * @return String
3633  */
3634 function wfBoolToStr( $value ) {
3635         return $value ? 'true' : 'false';
3636 }
3637
3638 /**
3639  * Get a platform-independent path to the null file, e.g. /dev/null
3640  *
3641  * @return string
3642  */
3643 function wfGetNull() {
3644         return wfIsWindows()
3645                 ? 'NUL'
3646                 : '/dev/null';
3647 }
3648
3649 /**
3650  * Modern version of wfWaitForSlaves(). Instead of looking at replication lag
3651  * and waiting for it to go down, this waits for the slaves to catch up to the
3652  * master position. Use this when updating very large numbers of rows, as
3653  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
3654  * a no-op if there are no slaves.
3655  *
3656  * @param $maxLag Integer (deprecated)
3657  * @param $wiki mixed Wiki identifier accepted by wfGetLB
3658  */
3659 function wfWaitForSlaves( $maxLag = false, $wiki = false ) {
3660         $lb = wfGetLB( $wiki );
3661         // bug 27975 - Don't try to wait for slaves if there are none
3662         // Prevents permission error when getting master position
3663         if ( $lb->getServerCount() > 1 ) {
3664                 $dbw = $lb->getConnection( DB_MASTER );
3665                 $pos = $dbw->getMasterPos();
3666                 $lb->waitForAll( $pos );
3667         }
3668 }
3669
3670 /**
3671  * Used to be used for outputting text in the installer/updater
3672  * @deprecated since 1.18, warnings in 1.18, remove in 1.20
3673  */
3674 function wfOut( $s ) {
3675         wfDeprecated( __FUNCTION__, '1.18' );
3676         global $wgCommandLineMode;
3677         if ( $wgCommandLineMode ) {
3678                 echo $s;
3679         } else {
3680                 echo htmlspecialchars( $s );
3681         }
3682         flush();
3683 }
3684
3685 /**
3686  * Count down from $n to zero on the terminal, with a one-second pause
3687  * between showing each number. For use in command-line scripts.
3688  * @codeCoverageIgnore
3689  * @param $n int
3690  */
3691 function wfCountDown( $n ) {
3692         for ( $i = $n; $i >= 0; $i-- ) {
3693                 if ( $i != $n ) {
3694                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3695                 }
3696                 echo $i;
3697                 flush();
3698                 if ( $i ) {
3699                         sleep( 1 );
3700                 }
3701         }
3702         echo "\n";
3703 }
3704
3705 /**
3706  * Generate a random 32-character hexadecimal token.
3707  * @param $salt Mixed: some sort of salt, if necessary, to add to random
3708  *              characters before hashing.
3709  * @return string
3710  * @codeCoverageIgnore
3711  * @deprecated since 1.20; Please use MWCryptRand for security purposes and wfRandomString for pesudo-random strings
3712  * @warning This method is NOT secure. Additionally it has many callers that use it for pesudo-random purposes.
3713  */
3714 function wfGenerateToken( $salt = '' ) {
3715         wfDeprecated( __METHOD__, '1.20' );
3716         $salt = serialize( $salt );
3717         return md5( mt_rand( 0, 0x7fffffff ) . $salt );
3718 }
3719
3720 /**
3721  * Replace all invalid characters with -
3722  * Additional characters can be defined in $wgIllegalFileChars (see bug 20489)
3723  * By default, $wgIllegalFileChars = ':'
3724  *
3725  * @param $name Mixed: filename to process
3726  * @return String
3727  */
3728 function wfStripIllegalFilenameChars( $name ) {
3729         global $wgIllegalFileChars;
3730         $illegalFileChars = $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '';
3731         $name = wfBaseName( $name );
3732         $name = preg_replace(
3733                 "/[^" . Title::legalChars() . "]" . $illegalFileChars . "/",
3734                 '-',
3735                 $name
3736         );
3737         return $name;
3738 }
3739
3740 /**
3741  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit;
3742  *
3743  * @return Integer value memory was set to.
3744  */
3745 function wfMemoryLimit() {
3746         global $wgMemoryLimit;
3747         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3748         if( $memlimit != -1 ) {
3749                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3750                 if( $conflimit == -1 ) {
3751                         wfDebug( "Removing PHP's memory limit\n" );
3752                         wfSuppressWarnings();
3753                         ini_set( 'memory_limit', $conflimit );
3754                         wfRestoreWarnings();
3755                         return $conflimit;
3756                 } elseif ( $conflimit > $memlimit ) {
3757                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3758                         wfSuppressWarnings();
3759                         ini_set( 'memory_limit', $conflimit );
3760                         wfRestoreWarnings();
3761                         return $conflimit;
3762                 }
3763         }
3764         return $memlimit;
3765 }
3766
3767 /**
3768  * Converts shorthand byte notation to integer form
3769  *
3770  * @param $string String
3771  * @return Integer
3772  */
3773 function wfShorthandToInteger( $string = '' ) {
3774         $string = trim( $string );
3775         if( $string === '' ) {
3776                 return -1;
3777         }
3778         $last = $string[strlen( $string ) - 1];
3779         $val = intval( $string );
3780         switch( $last ) {
3781                 case 'g':
3782                 case 'G':
3783                         $val *= 1024;
3784                         // break intentionally missing
3785                 case 'm':
3786                 case 'M':
3787                         $val *= 1024;
3788                         // break intentionally missing
3789                 case 'k':
3790                 case 'K':
3791                         $val *= 1024;
3792         }
3793
3794         return $val;
3795 }
3796
3797 /**
3798  * Get the normalised IETF language tag
3799  * See unit test for examples.
3800  *
3801  * @param $code String: The language code.
3802  * @return String: The language code which complying with BCP 47 standards.
3803  */
3804 function wfBCP47( $code ) {
3805         $codeSegment = explode( '-', $code );
3806         $codeBCP = array();
3807         foreach ( $codeSegment as $segNo => $seg ) {
3808                 if ( count( $codeSegment ) > 0 ) {
3809                         // when previous segment is x, it is a private segment and should be lc
3810                         if( $segNo > 0 && strtolower( $codeSegment[( $segNo - 1 )] ) == 'x' ) {
3811                                 $codeBCP[$segNo] = strtolower( $seg );
3812                         // ISO 3166 country code
3813                         } elseif ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3814                                 $codeBCP[$segNo] = strtoupper( $seg );
3815                         // ISO 15924 script code
3816                         } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3817                                 $codeBCP[$segNo] = ucfirst( strtolower( $seg ) );
3818                         // Use lowercase for other cases
3819                         } else {
3820                                 $codeBCP[$segNo] = strtolower( $seg );
3821                         }
3822                 } else {
3823                 // Use lowercase for single segment
3824                         $codeBCP[$segNo] = strtolower( $seg );
3825                 }
3826         }
3827         $langCode = implode( '-', $codeBCP );
3828         return $langCode;
3829 }
3830
3831 /**
3832  * Get a cache object.
3833  *
3834  * @param $inputType integer Cache type, one the the CACHE_* constants.
3835  * @return BagOStuff
3836  */
3837 function wfGetCache( $inputType ) {
3838         return ObjectCache::getInstance( $inputType );
3839 }
3840
3841 /**
3842  * Get the main cache object
3843  *
3844  * @return BagOStuff
3845  */
3846 function wfGetMainCache() {
3847         global $wgMainCacheType;
3848         return ObjectCache::getInstance( $wgMainCacheType );
3849 }
3850
3851 /**
3852  * Get the cache object used by the message cache
3853  *
3854  * @return BagOStuff
3855  */
3856 function wfGetMessageCacheStorage() {
3857         global $wgMessageCacheType;
3858         return ObjectCache::getInstance( $wgMessageCacheType );
3859 }
3860
3861 /**
3862  * Get the cache object used by the parser cache
3863  *
3864  * @return BagOStuff
3865  */
3866 function wfGetParserCacheStorage() {
3867         global $wgParserCacheType;
3868         return ObjectCache::getInstance( $wgParserCacheType );
3869 }
3870
3871 /**
3872  * Get the cache object used by the language converter
3873  *
3874  * @return BagOStuff
3875  */
3876 function wfGetLangConverterCacheStorage() {
3877         global $wgLanguageConverterCacheType;
3878         return ObjectCache::getInstance( $wgLanguageConverterCacheType );
3879 }
3880
3881 /**
3882  * Call hook functions defined in $wgHooks
3883  *
3884  * @param $event String: event name
3885  * @param $args Array: parameters passed to hook functions
3886  * @return Boolean True if no handler aborted the hook
3887  */
3888 function wfRunHooks( $event, $args = array() ) {
3889         return Hooks::run( $event, $args );
3890 }
3891
3892 /**
3893  * Wrapper around php's unpack.
3894  *
3895  * @param $format String: The format string (See php's docs)
3896  * @param $data: A binary string of binary data
3897  * @param $length integer or false: The minimun length of $data. This is to
3898  *      prevent reading beyond the end of $data. false to disable the check.
3899  *
3900  * Also be careful when using this function to read unsigned 32 bit integer
3901  * because php might make it negative.
3902  *
3903  * @throws MWException if $data not long enough, or if unpack fails
3904  * @return array Associative array of the extracted data
3905  */
3906 function wfUnpack( $format, $data, $length=false ) {
3907         if ( $length !== false ) {
3908                 $realLen = strlen( $data );
3909                 if ( $realLen < $length ) {
3910                         throw new MWException( "Tried to use wfUnpack on a "
3911                                 . "string of length $realLen, but needed one "
3912                                 . "of at least length $length."
3913                         );
3914                 }
3915         }
3916
3917         wfSuppressWarnings();
3918         $result = unpack( $format, $data );
3919         wfRestoreWarnings();
3920
3921         if ( $result === false ) {
3922                 // If it cannot extract the packed data.
3923                 throw new MWException( "unpack could not unpack binary data" );
3924         }
3925         return $result;
3926 }
3927
3928 /**
3929  * Determine if an image exists on the 'bad image list'.
3930  *
3931  * The format of MediaWiki:Bad_image_list is as follows:
3932  *    * Only list items (lines starting with "*") are considered
3933  *    * The first link on a line must be a link to a bad image
3934  *    * Any subsequent links on the same line are considered to be exceptions,
3935  *      i.e. articles where the image may occur inline.
3936  *
3937  * @param $name string the image name to check
3938  * @param $contextTitle Title|bool the page on which the image occurs, if known
3939  * @param $blacklist string wikitext of a file blacklist
3940  * @return bool
3941  */
3942 function wfIsBadImage( $name, $contextTitle = false, $blacklist = null ) {
3943         static $badImageCache = null; // based on bad_image_list msg
3944         wfProfileIn( __METHOD__ );
3945
3946         # Handle redirects
3947         $redirectTitle = RepoGroup::singleton()->checkRedirect( Title::makeTitle( NS_FILE, $name ) );
3948         if( $redirectTitle ) {
3949                 $name = $redirectTitle->getDbKey();
3950         }
3951
3952         # Run the extension hook
3953         $bad = false;
3954         if( !wfRunHooks( 'BadImage', array( $name, &$bad ) ) ) {
3955                 wfProfileOut( __METHOD__ );
3956                 return $bad;
3957         }
3958
3959         $cacheable = ( $blacklist === null );
3960         if( $cacheable && $badImageCache !== null ) {
3961                 $badImages = $badImageCache;
3962         } else { // cache miss
3963                 if ( $blacklist === null ) {
3964                         $blacklist = wfMessage( 'bad_image_list' )->inContentLanguage()->plain(); // site list
3965                 }
3966                 # Build the list now
3967                 $badImages = array();
3968                 $lines = explode( "\n", $blacklist );
3969                 foreach( $lines as $line ) {
3970                         # List items only
3971                         if ( substr( $line, 0, 1 ) !== '*' ) {
3972                                 continue;
3973                         }
3974
3975                         # Find all links
3976                         $m = array();
3977                         if ( !preg_match_all( '/\[\[:?(.*?)\]\]/', $line, $m ) ) {
3978                                 continue;
3979                         }
3980
3981                         $exceptions = array();
3982                         $imageDBkey = false;
3983                         foreach ( $m[1] as $i => $titleText ) {
3984                                 $title = Title::newFromText( $titleText );
3985                                 if ( !is_null( $title ) ) {
3986                                         if ( $i == 0 ) {
3987                                                 $imageDBkey = $title->getDBkey();
3988                                         } else {
3989                                                 $exceptions[$title->getPrefixedDBkey()] = true;
3990                                         }
3991                                 }
3992                         }
3993
3994                         if ( $imageDBkey !== false ) {
3995                                 $badImages[$imageDBkey] = $exceptions;
3996                         }
3997                 }
3998                 if ( $cacheable ) {
3999                         $badImageCache = $badImages;
4000                 }
4001         }
4002
4003         $contextKey = $contextTitle ? $contextTitle->getPrefixedDBkey() : false;
4004         $bad = isset( $badImages[$name] ) && !isset( $badImages[$name][$contextKey] );
4005         wfProfileOut( __METHOD__ );
4006         return $bad;
4007 }