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  */
 173 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
 174         if ( is_null( $changed ) ) {
 175                 throw new MWException( 'GlobalFunctions::wfAppendToArrayIfNotDefault got null' );
 176         }
 177         if ( $default[$key] !== $value ) {
 178                 $changed[$key] = $value;
 179         }
 180 }
 181
 182 /**
 183  * Backwards array plus for people who haven't bothered to read the PHP manual
 184  * XXX: will not darn your socks for you.
 185  *
 186  * @param $array1 Array
 187  * @param [$array2, [...]] Arrays
 188  * @return Array
 189  */
 190 function wfArrayMerge( $array1/* ... */ ) {
 191         $args = func_get_args();
 192         $args = array_reverse( $args, true );
 193         $out = array();
 194         foreach ( $args as $arg ) {
 195                 $out += $arg;
 196         }
 197         return $out;
 198 }
 199
 200 /**
 201  * Merge arrays in the style of getUserPermissionsErrors, with duplicate removal
 202  * e.g.
 203  *      wfMergeErrorArrays(
 204  *              array( array( 'x' ) ),
 205  *              array( array( 'x', '2' ) ),
 206  *              array( array( 'x' ) ),
 207  *              array( array( 'y' ) )
 208  *      );
 209  * returns:
 210  *              array(
 211  *              array( 'x', '2' ),
 212  *              array( 'x' ),
 213  *              array( 'y' )
 214  *      )
 215  * @param varargs
 216  * @return Array
 217  */
 218 function wfMergeErrorArrays( /*...*/ ) {
 219         $args = func_get_args();
 220         $out = array();
 221         foreach ( $args as $errors ) {
 222                 foreach ( $errors as $params ) {
 223                         # @todo FIXME: Sometimes get nested arrays for $params,
 224                         # which leads to E_NOTICEs
 225                         $spec = implode( "\t", $params );
 226                         $out[$spec] = $params;
 227                 }
 228         }
 229         return array_values( $out );
 230 }
 231
 232 /**
 233  * Insert array into another array after the specified *KEY*
 234  *
 235  * @param $array Array: The array.
 236  * @param $insert Array: The array to insert.
 237  * @param $after Mixed: The key to insert after
 238  * @return Array
 239  */
 240 function wfArrayInsertAfter( array $array, array $insert, $after ) {
 241         // Find the offset of the element to insert after.
 242         $keys = array_keys( $array );
 243         $offsetByKey = array_flip( $keys );
 244
 245         $offset = $offsetByKey[$after];
 246
 247         // Insert at the specified offset
 248         $before = array_slice( $array, 0, $offset + 1, true );
 249         $after = array_slice( $array, $offset + 1, count( $array ) - $offset, true );
 250
 251         $output = $before + $insert + $after;
 252
 253         return $output;
 254 }
 255
 256 /**
 257  * Recursively converts the parameter (an object) to an array with the same data
 258  *
 259  * @param $objOrArray Object|Array
 260  * @param $recursive Bool
 261  * @return Array
 262  */
 263 function wfObjectToArray( $objOrArray, $recursive = true ) {
 264         $array = array();
 265         if( is_object( $objOrArray ) ) {
 266                 $objOrArray = get_object_vars( $objOrArray );
 267         }
 268         foreach ( $objOrArray as $key => $value ) {
 269                 if ( $recursive && ( is_object( $value ) || is_array( $value ) ) ) {
 270                         $value = wfObjectToArray( $value );
 271                 }
 272
 273                 $array[$key] = $value;
 274         }
 275
 276         return $array;
 277 }
 278
 279 /**
 280  * Wrapper around array_map() which also taints variables
 281  *
 282  * @param  $function Callback
 283  * @param  $input Array
 284  * @return Array
 285  */
 286 function wfArrayMap( $function, $input ) {
 287         $ret = array_map( $function, $input );
 288         foreach ( $ret as $key => $value ) {
 289                 $taint = istainted( $input[$key] );
 290                 if ( $taint ) {
 291                         taint( $ret[$key], $taint );
 292                 }
 293         }
 294         return $ret;
 295 }
 296
 297 /**
 298  * Get a random decimal value between 0 and 1, in a way
 299  * not likely to give duplicate values for any realistic
 300  * number of articles.
 301  *
 302  * @return string
 303  */
 304 function wfRandom() {
 305         # The maximum random value is "only" 2^31-1, so get two random
 306         # values to reduce the chance of dupes
 307         $max = mt_getrandmax() + 1;
 308         $rand = number_format( ( mt_rand() * $max + mt_rand() )
 309                 / $max / $max, 12, '.', '' );
 310         return $rand;
 311 }
 312
 313 /**
 314  * Get a random string containing a number of pesudo-random hex
 315  * characters.
 316  * @note This is not secure, if you are trying to generate some sort
 317  *       of token please use MWCryptRand instead.
 318  *
 319  * @param $length int The length of the string to generate
 320  * @return String
 321  * @since 1.20
 322  */
 323 function wfRandomString( $length = 32 ) {
 324         $str = '';
 325         while ( strlen( $str ) < $length ) {
 326                 $str .= dechex( mt_rand() );
 327         }
 328         return substr( $str, 0, $length );
 329 }
 330
 331 /**
 332  * We want some things to be included as literal characters in our title URLs
 333  * for prettiness, which urlencode encodes by default.  According to RFC 1738,
 334  * all of the following should be safe:
 335  *
 336  * ;:@&=$-_.+!*'(),
 337  *
 338  * But + is not safe because it's used to indicate a space; &= are only safe in
 339  * paths and not in queries (and we don't distinguish here); ' seems kind of
 340  * scary; and urlencode() doesn't touch -_. to begin with.  Plus, although /
 341  * is reserved, we don't care.  So the list we unescape is:
 342  *
 343  * ;:@$!*(),/
 344  *
 345  * However, IIS7 redirects fail when the url contains a colon (Bug 22709),
 346  * so no fancy : for IIS7.
 347  *
 348  * %2F in the page titles seems to fatally break for some reason.
 349  *
 350  * @param $s String:
 351  * @return string
 352 */
 353 function wfUrlencode( $s ) {
 354         static $needle;
 355         if ( is_null( $s ) ) {
 356                 $needle = null;
 357                 return '';
 358         }
 359
 360         if ( is_null( $needle ) ) {
 361                 $needle = array( '%3B', '%40', '%24', '%21', '%2A', '%28', '%29', '%2C', '%2F' );
 362                 if ( !isset( $_SERVER['SERVER_SOFTWARE'] ) || ( strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/7' ) === false ) ) {
 363                         $needle[] = '%3A';
 364                 }
 365         }
 366
 367         $s = urlencode( $s );
 368         $s = str_ireplace(
 369                 $needle,
 370                 array( ';', '@', '$', '!', '*', '(', ')', ',', '/', ':' ),
 371                 $s
 372         );
 373
 374         return $s;
 375 }
 376
 377 /**
 378  * This function takes two arrays as input, and returns a CGI-style string, e.g.
 379  * "days=7&limit=100". Options in the first array override options in the second.
 380  * Options set to null or false will not be output.
 381  *
 382  * @param $array1 Array ( String|Array )
 383  * @param $array2 Array ( String|Array )
 384  * @param $prefix String
 385  * @return String
 386  */
 387 function wfArrayToCgi( $array1, $array2 = null, $prefix = '' ) {
 388         if ( !is_null( $array2 ) ) {
 389                 $array1 = $array1 + $array2;
 390         }
 391
 392         $cgi = '';
 393         foreach ( $array1 as $key => $value ) {
 394                 if ( !is_null($value) && $value !== false ) {
 395                         if ( $cgi != '' ) {
 396                                 $cgi .= '&';
 397                         }
 398                         if ( $prefix !== '' ) {
 399                                 $key = $prefix . "[$key]";
 400                         }
 401                         if ( is_array( $value ) ) {
 402                                 $firstTime = true;
 403                                 foreach ( $value as $k => $v ) {
 404                                         $cgi .= $firstTime ? '' : '&';
 405                                         if ( is_array( $v ) ) {
 406                                                 $cgi .= wfArrayToCgi( $v, null, $key . "[$k]" );
 407                                         } else {
 408                                                 $cgi .= urlencode( $key . "[$k]" ) . '=' . urlencode( $v );
 409                                         }
 410                                         $firstTime = false;
 411                                 }
 412                         } else {
 413                                 if ( is_object( $value ) ) {
 414                                         $value = $value->__toString();
 415                                 }
 416                                 $cgi .= urlencode( $key ) . '=' . urlencode( $value );
 417                         }
 418                 }
 419         }
 420         return $cgi;
 421 }
 422
 423 /**
 424  * This is the logical opposite of wfArrayToCgi(): it accepts a query string as
 425  * its argument and returns the same string in array form.  This allows compa-
 426  * tibility with legacy functions that accept raw query strings instead of nice
 427  * arrays.  Of course, keys and values are urldecode()d.
 428  *
 429  * @param $query String: query string
 430  * @return array Array version of input
 431  */
 432 function wfCgiToArray( $query ) {
 433         if ( isset( $query[0] ) && $query[0] == '?' ) {
 434                 $query = substr( $query, 1 );
 435         }
 436         $bits = explode( '&', $query );
 437         $ret = array();
 438         foreach ( $bits as $bit ) {
 439                 if ( $bit === '' ) {
 440                         continue;
 441                 }
 442                 if ( strpos( $bit, '=' ) === false ) {
 443                         // Pieces like &qwerty become 'qwerty' => '' (at least this is what php does)
 444                         $key = $bit;
 445                         $value = '';
 446                 } else {
 447                         list( $key, $value ) = explode( '=', $bit );
 448                 }
 449                 $key = urldecode( $key );
 450                 $value = urldecode( $value );
 451                 if ( strpos( $key, '[' ) !== false ) {
 452                         $keys = array_reverse( explode( '[', $key ) );
 453                         $key = array_pop( $keys );
 454                         $temp = $value;
 455                         foreach ( $keys as $k ) {
 456                                 $k = substr( $k, 0, -1 );
 457                                 $temp = array( $k => $temp );
 458                         }
 459                         if ( isset( $ret[$key] ) ) {
 460                                 $ret[$key] = array_merge( $ret[$key], $temp );
 461                         } else {
 462                                 $ret[$key] = $temp;
 463                         }
 464                 } else {
 465                         $ret[$key] = $value;
 466                 }
 467         }
 468         return $ret;
 469 }
 470
 471 /**
 472  * Append a query string to an existing URL, which may or may not already
 473  * have query string parameters already. If so, they will be combined.
 474  *
 475  * @param $url String
 476  * @param $query Mixed: string or associative array
 477  * @return string
 478  */
 479 function wfAppendQuery( $url, $query ) {
 480         if ( is_array( $query ) ) {
 481                 $query = wfArrayToCgi( $query );
 482         }
 483         if( $query != '' ) {
 484                 if( false === strpos( $url, '?' ) ) {
 485                         $url .= '?';
 486                 } else {
 487                         $url .= '&';
 488                 }
 489                 $url .= $query;
 490         }
 491         return $url;
 492 }
 493
 494 /**
 495  * Expand a potentially local URL to a fully-qualified URL.  Assumes $wgServer
 496  * is correct.
 497  *
 498  * The meaning of the PROTO_* constants is as follows:
 499  * PROTO_HTTP: Output a URL starting with http://
 500  * PROTO_HTTPS: Output a URL starting with https://
 501  * PROTO_RELATIVE: Output a URL starting with // (protocol-relative URL)
 502  * PROTO_CURRENT: Output a URL starting with either http:// or https:// , depending on which protocol was used for the current incoming request
 503  * PROTO_CANONICAL: For URLs without a domain, like /w/index.php , use $wgCanonicalServer. For protocol-relative URLs, use the protocol of $wgCanonicalServer
 504  * PROTO_INTERNAL: Like PROTO_CANONICAL, but uses $wgInternalServer instead of $wgCanonicalServer
 505  *
 506  * @todo this won't work with current-path-relative URLs
 507  * like "subdir/foo.html", etc.
 508  *
 509  * @param $url String: either fully-qualified or a local path + query
 510  * @param $defaultProto Mixed: one of the PROTO_* constants. Determines the
 511  *                             protocol to use if $url or $wgServer is
 512  *                             protocol-relative
 513  * @return string Fully-qualified URL, current-path-relative URL or false if
 514  *                no valid URL can be constructed
 515  */
 516 function wfExpandUrl( $url, $defaultProto = PROTO_CURRENT ) {
 517         global $wgServer, $wgCanonicalServer, $wgInternalServer;
 518         $serverUrl = $wgServer;
 519         if ( $defaultProto === PROTO_CANONICAL ) {
 520                 $serverUrl = $wgCanonicalServer;
 521         }
 522         // Make $wgInternalServer fall back to $wgServer if not set
 523         if ( $defaultProto === PROTO_INTERNAL && $wgInternalServer !== false ) {
 524                 $serverUrl = $wgInternalServer;
 525         }
 526         if ( $defaultProto === PROTO_CURRENT ) {
 527                 $defaultProto = WebRequest::detectProtocol() . '://';
 528         }
 529
 530         // Analyze $serverUrl to obtain its protocol
 531         $bits = wfParseUrl( $serverUrl );
 532         $serverHasProto = $bits && $bits['scheme'] != '';
 533
 534         if ( $defaultProto === PROTO_CANONICAL || $defaultProto === PROTO_INTERNAL ) {
 535                 if ( $serverHasProto ) {
 536                         $defaultProto = $bits['scheme'] . '://';
 537                 } else {
 538                         // $wgCanonicalServer or $wgInternalServer doesn't have a protocol. This really isn't supposed to happen
 539                         // Fall back to HTTP in this ridiculous case
 540                         $defaultProto = PROTO_HTTP;
 541                 }
 542         }
 543
 544         $defaultProtoWithoutSlashes = substr( $defaultProto, 0, -2 );
 545
 546         if ( substr( $url, 0, 2 ) == '//' ) {
 547                 $url = $defaultProtoWithoutSlashes . $url;
 548         } elseif ( substr( $url, 0, 1 ) == '/' ) {
 549                 // If $serverUrl is protocol-relative, prepend $defaultProtoWithoutSlashes, otherwise leave it alone
 550                 $url = ( $serverHasProto ? '' : $defaultProtoWithoutSlashes ) . $serverUrl . $url;
 551         }
 552
 553         $bits = wfParseUrl( $url );
 554         if ( $bits && isset( $bits['path'] ) ) {
 555                 $bits['path'] = wfRemoveDotSegments( $bits['path'] );
 556                 return wfAssembleUrl( $bits );
 557         } elseif ( $bits ) {
 558                 # No path to expand
 559                 return $url;
 560         } elseif ( substr( $url, 0, 1 ) != '/' ) {
 561                 # URL is a relative path
 562                 return wfRemoveDotSegments( $url );
 563         }
 564
 565         # Expanded URL is not valid.
 566         return false;
 567 }
 568
 569 /**
 570  * This function will reassemble a URL parsed with wfParseURL.  This is useful
 571  * if you need to edit part of a URL and put it back together.
 572  *
 573  * This is the basic structure used (brackets contain keys for $urlParts):
 574  * [scheme][delimiter][user]:[pass]@[host]:[port][path]?[query]#[fragment]
 575  *
 576  * @todo Need to integrate this into wfExpandUrl (bug 32168)
 577  *
 578  * @since 1.19
 579  * @param $urlParts Array URL parts, as output from wfParseUrl
 580  * @return string URL assembled from its component parts
 581  */
 582 function wfAssembleUrl( $urlParts ) {
 583         $result = '';
 584
 585         if ( isset( $urlParts['delimiter'] ) ) {
 586                 if ( isset( $urlParts['scheme'] ) ) {
 587                         $result .= $urlParts['scheme'];
 588                 }
 589
 590                 $result .= $urlParts['delimiter'];
 591         }
 592
 593         if ( isset( $urlParts['host'] ) ) {
 594                 if ( isset( $urlParts['user'] ) ) {
 595                         $result .= $urlParts['user'];
 596                         if ( isset( $urlParts['pass'] ) ) {
 597                                 $result .= ':' . $urlParts['pass'];
 598                         }
 599                         $result .= '@';
 600                 }
 601
 602                 $result .= $urlParts['host'];
 603
 604                 if ( isset( $urlParts['port'] ) ) {
 605                         $result .= ':' . $urlParts['port'];
 606                 }
 607         }
 608
 609         if ( isset( $urlParts['path'] ) ) {
 610                 $result .= $urlParts['path'];
 611         }
 612
 613         if ( isset( $urlParts['query'] ) ) {
 614                 $result .= '?' . $urlParts['query'];
 615         }
 616
 617         if ( isset( $urlParts['fragment'] ) ) {
 618                 $result .= '#' . $urlParts['fragment'];
 619         }
 620
 621         return $result;
 622 }
 623
 624 /**
 625  * Remove all dot-segments in the provided URL path.  For example,
 626  * '/a/./b/../c/' becomes '/a/c/'.  For details on the algorithm, please see
 627  * RFC3986 section 5.2.4.
 628  *
 629  * @todo Need to integrate this into wfExpandUrl (bug 32168)
 630  *
 631  * @param $urlPath String URL path, potentially containing dot-segments
 632  * @return string URL path with all dot-segments removed
 633  */
 634 function wfRemoveDotSegments( $urlPath ) {
 635         $output = '';
 636         $inputOffset = 0;
 637         $inputLength = strlen( $urlPath );
 638
 639         while ( $inputOffset < $inputLength ) {
 640                 $prefixLengthOne = substr( $urlPath, $inputOffset, 1 );
 641                 $prefixLengthTwo = substr( $urlPath, $inputOffset, 2 );
 642                 $prefixLengthThree = substr( $urlPath, $inputOffset, 3 );
 643                 $prefixLengthFour = substr( $urlPath, $inputOffset, 4 );
 644                 $trimOutput = false;
 645
 646                 if ( $prefixLengthTwo == './' ) {
 647                         # Step A, remove leading "./"
 648                         $inputOffset += 2;
 649                 } elseif ( $prefixLengthThree == '../' ) {
 650                         # Step A, remove leading "../"
 651                         $inputOffset += 3;
 652                 } elseif ( ( $prefixLengthTwo == '/.' ) && ( $inputOffset + 2 == $inputLength ) ) {
 653                         # Step B, replace leading "/.$" with "/"
 654                         $inputOffset += 1;
 655                         $urlPath[$inputOffset] = '/';
 656                 } elseif ( $prefixLengthThree == '/./' ) {
 657                         # Step B, replace leading "/./" with "/"
 658                         $inputOffset += 2;
 659                 } elseif ( $prefixLengthThree == '/..' && ( $inputOffset + 3 == $inputLength ) ) {
 660                         # Step C, replace leading "/..$" with "/" and
 661                         # remove last path component in output
 662                         $inputOffset += 2;
 663                         $urlPath[$inputOffset] = '/';
 664                         $trimOutput = true;
 665                 } elseif ( $prefixLengthFour == '/../' ) {
 666                         # Step C, replace leading "/../" with "/" and
 667                         # remove last path component in output
 668                         $inputOffset += 3;
 669                         $trimOutput = true;
 670                 } elseif ( ( $prefixLengthOne == '.' ) && ( $inputOffset + 1 == $inputLength ) ) {
 671                         # Step D, remove "^.$"
 672                         $inputOffset += 1;
 673                 } elseif ( ( $prefixLengthTwo == '..' ) && ( $inputOffset + 2 == $inputLength ) ) {
 674                         # Step D, remove "^..$"
 675                         $inputOffset += 2;
 676                 } else {
 677                         # Step E, move leading path segment to output
 678                         if ( $prefixLengthOne == '/' ) {
 679                                 $slashPos = strpos( $urlPath, '/', $inputOffset + 1 );
 680                         } else {
 681                                 $slashPos = strpos( $urlPath, '/', $inputOffset );
 682                         }
 683                         if ( $slashPos === false ) {
 684                                 $output .= substr( $urlPath, $inputOffset );
 685                                 $inputOffset = $inputLength;
 686                         } else {
 687                                 $output .= substr( $urlPath, $inputOffset, $slashPos - $inputOffset );
 688                                 $inputOffset += $slashPos - $inputOffset;
 689                         }
 690                 }
 691
 692                 if ( $trimOutput ) {
 693                         $slashPos = strrpos( $output, '/' );
 694                         if ( $slashPos === false ) {
 695                                 $output = '';
 696                         } else {
 697                                 $output = substr( $output, 0, $slashPos );
 698                         }
 699                 }
 700         }
 701
 702         return $output;
 703 }
 704
 705 /**
 706  * Returns a regular expression of url protocols
 707  *
 708  * @param $includeProtocolRelative bool If false, remove '//' from the returned protocol list.
 709  *        DO NOT USE this directly, use wfUrlProtocolsWithoutProtRel() instead
 710  * @return String
 711  */
 712 function wfUrlProtocols( $includeProtocolRelative = true ) {
 713         global $wgUrlProtocols;
 714
 715         // Cache return values separately based on $includeProtocolRelative
 716         static $withProtRel = null, $withoutProtRel = null;
 717         $cachedValue = $includeProtocolRelative ? $withProtRel : $withoutProtRel;
 718         if ( !is_null( $cachedValue ) ) {
 719                 return $cachedValue;
 720         }
 721
 722         // Support old-style $wgUrlProtocols strings, for backwards compatibility
 723         // with LocalSettings files from 1.5
 724         if ( is_array( $wgUrlProtocols ) ) {
 725                 $protocols = array();
 726                 foreach ( $wgUrlProtocols as $protocol ) {
 727                         // Filter out '//' if !$includeProtocolRelative
 728                         if ( $includeProtocolRelative || $protocol !== '//' ) {
 729                                 $protocols[] = preg_quote( $protocol, '/' );
 730                         }
 731                 }
 732
 733                 $retval = implode( '|', $protocols );
 734         } else {
 735                 // Ignore $includeProtocolRelative in this case
 736                 // This case exists for pre-1.6 compatibility, and we can safely assume
 737                 // that '//' won't appear in a pre-1.6 config because protocol-relative
 738                 // URLs weren't supported until 1.18
 739                 $retval = $wgUrlProtocols;
 740         }
 741
 742         // Cache return value
 743         if ( $includeProtocolRelative ) {
 744                 $withProtRel = $retval;
 745         } else {
 746                 $withoutProtRel = $retval;
 747         }
 748         return $retval;
 749 }
 750
 751 /**
 752  * Like wfUrlProtocols(), but excludes '//' from the protocol list. Use this if
 753  * you need a regex that matches all URL protocols but does not match protocol-
 754  * relative URLs
 755  * @return String
 756  */
 757 function wfUrlProtocolsWithoutProtRel() {
 758         return wfUrlProtocols( false );
 759 }
 760
 761 /**
 762  * parse_url() work-alike, but non-broken.  Differences:
 763  *
 764  * 1) Does not raise warnings on bad URLs (just returns false)
 765  * 2) Handles protocols that don't use :// (e.g., mailto: and news: , as well as protocol-relative URLs) correctly
 766  * 3) Adds a "delimiter" element to the array, either '://', ':' or '//' (see (2))
 767  *
 768  * @param $url String: a URL to parse
 769  * @return Array: bits of the URL in an associative array, per PHP docs
 770  */
 771 function wfParseUrl( $url ) {
 772         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
 773
 774         // Protocol-relative URLs are handled really badly by parse_url(). It's so bad that the easiest
 775         // way to handle them is to just prepend 'http:' and strip the protocol out later
 776         $wasRelative = substr( $url, 0, 2 ) == '//';
 777         if ( $wasRelative ) {
 778                 $url = "http:$url";
 779         }
 780         wfSuppressWarnings();
 781         $bits = parse_url( $url );
 782         wfRestoreWarnings();
 783         // parse_url() returns an array without scheme for some invalid URLs, e.g.
 784         // parse_url("%0Ahttp://example.com") == array( 'host' => '%0Ahttp', 'path' => 'example.com' )
 785         if ( !$bits || !isset( $bits['scheme'] ) ) {
 786                 return false;
 787         }
 788
 789         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
 790         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
 791                 $bits['delimiter'] = '://';
 792         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
 793                 $bits['delimiter'] = ':';
 794                 // parse_url detects for news: and mailto: the host part of an url as path
 795                 // We have to correct this wrong detection
 796                 if ( isset( $bits['path'] ) ) {
 797                         $bits['host'] = $bits['path'];
 798                         $bits['path'] = '';
 799                 }
 800         } else {
 801                 return false;
 802         }
 803
 804         /* Provide an empty host for eg. file:/// urls (see bug 28627) */
 805         if ( !isset( $bits['host'] ) ) {
 806                 $bits['host'] = '';
 807
 808                 /* parse_url loses the third / for file:///c:/ urls (but not on variants) */
 809                 if ( substr( $bits['path'], 0, 1 ) !== '/' ) {
 810                         $bits['path'] = '/' . $bits['path'];
 811                 }
 812         }
 813
 814         // If the URL was protocol-relative, fix scheme and delimiter
 815         if ( $wasRelative ) {
 816                 $bits['scheme'] = '';
 817                 $bits['delimiter'] = '//';
 818         }
 819         return $bits;
 820 }
 821
 822 /**
 823  * Take a URL, make sure it's expanded to fully qualified, and replace any
 824  * encoded non-ASCII Unicode characters with their UTF-8 original forms
 825  * for more compact display and legibility for local audiences.
 826  *
 827  * @todo handle punycode domains too
 828  *
 829  * @param $url string
 830  * @return string
 831  */
 832 function wfExpandIRI( $url ) {
 833         return preg_replace_callback( '/((?:%[89A-F][0-9A-F])+)/i', 'wfExpandIRI_callback', wfExpandUrl( $url ) );
 834 }
 835
 836 /**
 837  * Private callback for wfExpandIRI
 838  * @param array $matches
 839  * @return string
 840  */
 841 function wfExpandIRI_callback( $matches ) {
 842         return urldecode( $matches[1] );
 843 }
 844
 845
 846
 847 /**
 848  * Make URL indexes, appropriate for the el_index field of externallinks.
 849  *
 850  * @param $url String
 851  * @return array
 852  */
 853 function wfMakeUrlIndexes( $url ) {
 854         $bits = wfParseUrl( $url );
 855
 856         // Reverse the labels in the hostname, convert to lower case
 857         // For emails reverse domainpart only
 858         if ( $bits['scheme'] == 'mailto' ) {
 859                 $mailparts = explode( '@', $bits['host'], 2 );
 860                 if ( count( $mailparts ) === 2 ) {
 861                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
 862                 } else {
 863                         // No domain specified, don't mangle it
 864                         $domainpart = '';
 865                 }
 866                 $reversedHost = $domainpart . '@' . $mailparts[0];
 867         } else {
 868                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
 869         }
 870         // Add an extra dot to the end
 871         // Why? Is it in wrong place in mailto links?
 872         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
 873                 $reversedHost .= '.';
 874         }
 875         // Reconstruct the pseudo-URL
 876         $prot = $bits['scheme'];
 877         $index = $prot . $bits['delimiter'] . $reversedHost;
 878         // Leave out user and password. Add the port, path, query and fragment
 879         if ( isset( $bits['port'] ) ) {
 880                 $index .= ':' . $bits['port'];
 881         }
 882         if ( isset( $bits['path'] ) ) {
 883                 $index .= $bits['path'];
 884         } else {
 885                 $index .= '/';
 886         }
 887         if ( isset( $bits['query'] ) ) {
 888                 $index .= '?' . $bits['query'];
 889         }
 890         if ( isset( $bits['fragment'] ) ) {
 891                 $index .= '#' . $bits['fragment'];
 892         }
 893
 894         if ( $prot == '' ) {
 895                 return array( "http:$index", "https:$index" );
 896         } else {
 897                 return array( $index );
 898         }
 899 }
 900
 901 /**
 902  * Check whether a given URL has a domain that occurs in a given set of domains
 903  * @param $url string URL
 904  * @param $domains array Array of domains (strings)
 905  * @return bool True if the host part of $url ends in one of the strings in $domains
 906  */
 907 function wfMatchesDomainList( $url, $domains ) {
 908         $bits = wfParseUrl( $url );
 909         if ( is_array( $bits ) && isset( $bits['host'] ) ) {
 910                 foreach ( (array)$domains as $domain ) {
 911                         // FIXME: This gives false positives. http://nds-nl.wikipedia.org will match nl.wikipedia.org
 912                         // We should use something that interprets dots instead
 913                         if ( substr( $bits['host'], -strlen( $domain ) ) === $domain ) {
 914                                 return true;
 915                         }
 916                 }
 917         }
 918         return false;
 919 }
 920
 921 /**
 922  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
 923  * In normal operation this is a NOP.
 924  *
 925  * Controlling globals:
 926  * $wgDebugLogFile - points to the log file
 927  * $wgProfileOnly - if set, normal debug messages will not be recorded.
 928  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
 929  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
 930  *
 931  * @param $text String
 932  * @param $logonly Bool: set true to avoid appearing in HTML when $wgDebugComments is set
 933  */
 934 function wfDebug( $text, $logonly = false ) {
 935         global $wgOut, $wgDebugLogFile, $wgDebugComments, $wgProfileOnly, $wgDebugRawPage;
 936         global $wgDebugLogPrefix, $wgShowDebug;
 937
 938         static $cache = array(); // Cache of unoutputted messages
 939
 940         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
 941                 return;
 942         }
 943
 944         $timer = wfDebugTimer();
 945         if ( $timer !== '' ) {
 946                 $text = preg_replace( '/[^\n]/', $timer . '\0', $text, 1 );
 947         }
 948
 949         if ( ( $wgDebugComments || $wgShowDebug ) && !$logonly ) {
 950                 $cache[] = $text;
 951
 952                 if ( isset( $wgOut ) && is_object( $wgOut ) ) {
 953                         // add the message and any cached messages to the output
 954                         array_map( array( $wgOut, 'debug' ), $cache );
 955                         $cache = array();
 956                 }
 957         }
 958         if ( wfRunHooks( 'Debug', array( $text, null /* no log group */ ) ) ) {
 959                 if ( $wgDebugLogFile != '' && !$wgProfileOnly ) {
 960                         # Strip unprintables; they can switch terminal modes when binary data
 961                         # gets dumped, which is pretty annoying.
 962                         $text = preg_replace( '![\x00-\x08\x0b\x0c\x0e-\x1f]!', ' ', $text );
 963                         $text = $wgDebugLogPrefix . $text;
 964                         wfErrorLog( $text, $wgDebugLogFile );
 965                 }
 966         }
 967
 968         MWDebug::debugMsg( $text );
 969 }
 970
 971 /**
 972  * Returns true if debug logging should be suppressed if $wgDebugRawPage = false
 973  * @return bool
 974  */
 975 function wfIsDebugRawPage() {
 976         static $cache;
 977         if ( $cache !== null ) {
 978                 return $cache;
 979         }
 980         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
 981         if ( ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' )
 982                 || (
 983                         isset( $_SERVER['SCRIPT_NAME'] )
 984                         && substr( $_SERVER['SCRIPT_NAME'], -8 ) == 'load.php'
 985                 ) )
 986         {
 987                 $cache = true;
 988         } else {
 989                 $cache = false;
 990         }
 991         return $cache;
 992 }
 993
 994 /**
 995  * Get microsecond timestamps for debug logs
 996  *
 997  * @return string
 998  */
 999 function wfDebugTimer() {
1000         global $wgDebugTimestamps, $wgRequestTime;
1001
1002         if ( !$wgDebugTimestamps ) {
1003                 return '';
1004         }
1005
1006         $prefix = sprintf( "%6.4f", microtime( true ) - $wgRequestTime );
1007         $mem = sprintf( "%5.1fM", ( memory_get_usage( true ) / ( 1024 * 1024 ) ) );
1008         return "$prefix $mem  ";
1009 }
1010
1011 /**
1012  * Send a line giving PHP memory usage.
1013  *
1014  * @param $exact Bool: print exact values instead of kilobytes (default: false)
1015  */
1016 function wfDebugMem( $exact = false ) {
1017         $mem = memory_get_usage();
1018         if( !$exact ) {
1019                 $mem = floor( $mem / 1024 ) . ' kilobytes';
1020         } else {
1021                 $mem .= ' bytes';
1022         }
1023         wfDebug( "Memory usage: $mem\n" );
1024 }
1025
1026 /**
1027  * Send a line to a supplementary debug log file, if configured, or main debug log if not.
1028  * $wgDebugLogGroups[$logGroup] should be set to a filename to send to a separate log.
1029  *
1030  * @param $logGroup String
1031  * @param $text String
1032  * @param $public Bool: whether to log the event in the public log if no private
1033  *                     log file is specified, (default true)
1034  */
1035 function wfDebugLog( $logGroup, $text, $public = true ) {
1036         global $wgDebugLogGroups;
1037         $text = trim( $text ) . "\n";
1038         if( isset( $wgDebugLogGroups[$logGroup] ) ) {
1039                 $time = wfTimestamp( TS_DB );
1040                 $wiki = wfWikiID();
1041                 $host = wfHostname();
1042                 if ( wfRunHooks( 'Debug', array( $text, $logGroup ) ) ) {
1043                         wfErrorLog( "$time $host $wiki: $text", $wgDebugLogGroups[$logGroup] );
1044                 }
1045         } elseif ( $public === true ) {
1046                 wfDebug( $text, true );
1047         }
1048 }
1049
1050 /**
1051  * Log for database errors
1052  *
1053  * @param $text String: database error message.
1054  */
1055 function wfLogDBError( $text ) {
1056         global $wgDBerrorLog;
1057         if ( $wgDBerrorLog ) {
1058                 $host = wfHostname();
1059                 $wiki = wfWikiID();
1060                 $text = date( 'D M j G:i:s T Y' ) . "\t$host\t$wiki\t$text";
1061                 wfErrorLog( $text, $wgDBerrorLog );
1062         }
1063 }
1064
1065 /**
1066  * Throws a warning that $function is deprecated
1067  *
1068  * @param $function String
1069  * @param $version String|bool: Version of MediaWiki that the function was deprecated in (Added in 1.19).
1070  * @param $component String|bool: Added in 1.19.
1071  * @param $callerOffset integer: How far up the callstack is the original
1072  *    caller. 2 = function that called the function that called
1073  *    wfDeprecated (Added in 1.20)
1074  *
1075  * @return null
1076  */
1077 function wfDeprecated( $function, $version = false, $component = false, $callerOffset = 2 ) {
1078         static $functionsWarned = array();
1079
1080         MWDebug::deprecated( $function, $version, $component );
1081
1082         if ( !isset( $functionsWarned[$function] ) ) {
1083                 $functionsWarned[$function] = true;
1084
1085                 if ( $version ) {
1086                         global $wgDeprecationReleaseLimit;
1087
1088                         if ( $wgDeprecationReleaseLimit && $component === false ) {
1089                                 # Strip -* off the end of $version so that branches can use the
1090                                 # format #.##-branchname to avoid issues if the branch is merged into
1091                                 # a version of MediaWiki later than what it was branched from
1092                                 $comparableVersion = preg_replace( '/-.*$/', '', $version );
1093
1094                                 # If the comparableVersion is larger than our release limit then
1095                                 # skip the warning message for the deprecation
1096                                 if ( version_compare( $wgDeprecationReleaseLimit, $comparableVersion, '<' ) ) {
1097                                         return;
1098                                 }
1099                         }
1100
1101                         $component = $component === false ? 'MediaWiki' : $component;
1102                         wfWarn( "Use of $function was deprecated in $component $version.", $callerOffset );
1103                 } else {
1104                         wfWarn( "Use of $function is deprecated.", $callerOffset );
1105                 }
1106         }
1107 }
1108
1109 /**
1110  * Send a warning either to the debug log or in a PHP error depending on
1111  * $wgDevelopmentWarnings
1112  *
1113  * @param $msg String: message to send
1114  * @param $callerOffset Integer: number of items to go back in the backtrace to
1115  *        find the correct caller (1 = function calling wfWarn, ...)
1116  * @param $level Integer: PHP error level; only used when $wgDevelopmentWarnings
1117  *        is true
1118  */
1119 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
1120         global $wgDevelopmentWarnings;
1121
1122         MWDebug::warning( $msg, $callerOffset + 2 );
1123
1124         $callers = wfDebugBacktrace();
1125         if ( isset( $callers[$callerOffset + 1] ) ) {
1126                 $callerfunc = $callers[$callerOffset + 1];
1127                 $callerfile = $callers[$callerOffset];
1128                 if ( isset( $callerfile['file'] ) && isset( $callerfile['line'] ) ) {
1129                         $file = $callerfile['file'] . ' at line ' . $callerfile['line'];
1130                 } else {
1131                         $file = '(internal function)';
1132                 }
1133                 $func = '';
1134                 if ( isset( $callerfunc['class'] ) ) {
1135                         $func .= $callerfunc['class'] . '::';
1136                 }
1137                 if ( isset( $callerfunc['function'] ) ) {
1138                         $func .= $callerfunc['function'];
1139                 }
1140                 $msg .= " [Called from $func in $file]";
1141         }
1142
1143         if ( $wgDevelopmentWarnings ) {
1144                 trigger_error( $msg, $level );
1145         } else {
1146                 wfDebug( "$msg\n" );
1147         }
1148 }
1149
1150 /**
1151  * Log to a file without getting "file size exceeded" signals.
1152  *
1153  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
1154  * send lines to the specified port, prefixed by the specified prefix and a space.
1155  *
1156  * @param $text String
1157  * @param $file String filename
1158  */
1159 function wfErrorLog( $text, $file ) {
1160         if ( substr( $file, 0, 4 ) == 'udp:' ) {
1161                 # Needs the sockets extension
1162                 if ( preg_match( '!^(tcp|udp):(?://)?\[([0-9a-fA-F:]+)\]:(\d+)(?:/(.*))?$!', $file, $m ) ) {
1163                         // IPv6 bracketed host
1164                         $host = $m[2];
1165                         $port = intval( $m[3] );
1166                         $prefix = isset( $m[4] ) ? $m[4] : false;
1167                         $domain = AF_INET6;
1168                 } elseif ( preg_match( '!^(tcp|udp):(?://)?([a-zA-Z0-9.-]+):(\d+)(?:/(.*))?$!', $file, $m ) ) {
1169                         $host = $m[2];
1170                         if ( !IP::isIPv4( $host ) ) {
1171                                 $host = gethostbyname( $host );
1172                         }
1173                         $port = intval( $m[3] );
1174                         $prefix = isset( $m[4] ) ? $m[4] : false;
1175                         $domain = AF_INET;
1176                 } else {
1177                         throw new MWException( __METHOD__ . ': Invalid UDP specification' );
1178                 }
1179
1180                 // Clean it up for the multiplexer
1181                 if ( strval( $prefix ) !== '' ) {
1182                         $text = preg_replace( '/^/m', $prefix . ' ', $text );
1183
1184                         // Limit to 64KB
1185                         if ( strlen( $text ) > 65506 ) {
1186                                 $text = substr( $text, 0, 65506 );
1187                         }
1188
1189                         if ( substr( $text, -1 ) != "\n" ) {
1190                                 $text .= "\n";
1191                         }
1192                 } elseif ( strlen( $text ) > 65507 ) {
1193                         $text = substr( $text, 0, 65507 );
1194                 }
1195
1196                 $sock = socket_create( $domain, SOCK_DGRAM, SOL_UDP );
1197                 if ( !$sock ) {
1198                         return;
1199                 }
1200
1201                 socket_sendto( $sock, $text, strlen( $text ), 0, $host, $port );
1202                 socket_close( $sock );
1203         } else {
1204                 wfSuppressWarnings();
1205                 $exists = file_exists( $file );
1206                 $size = $exists ? filesize( $file ) : false;
1207                 if ( !$exists || ( $size !== false && $size + strlen( $text ) < 0x7fffffff ) ) {
1208                         file_put_contents( $file, $text, FILE_APPEND );
1209                 }
1210                 wfRestoreWarnings();
1211         }
1212 }
1213
1214 /**
1215  * @todo document
1216  */
1217 function wfLogProfilingData() {
1218         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
1219         global $wgProfileLimit, $wgUser;
1220
1221         $profiler = Profiler::instance();
1222
1223         # Profiling must actually be enabled...
1224         if ( $profiler->isStub() ) {
1225                 return;
1226         }
1227
1228         // Get total page request time and only show pages that longer than
1229         // $wgProfileLimit time (default is 0)
1230         $elapsed = microtime( true ) - $wgRequestTime;
1231         if ( $elapsed <= $wgProfileLimit ) {
1232                 return;
1233         }
1234
1235         $profiler->logData();
1236
1237         // Check whether this should be logged in the debug file.
1238         if ( $wgDebugLogFile == '' || ( !$wgDebugRawPage && wfIsDebugRawPage() ) ) {
1239                 return;
1240         }
1241
1242         $forward = '';
1243         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
1244                 $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
1245         }
1246         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
1247                 $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
1248         }
1249         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
1250                 $forward .= ' from ' . $_SERVER['HTTP_FROM'];
1251         }
1252         if ( $forward ) {
1253                 $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
1254         }
1255         // Don't load $wgUser at this late stage just for statistics purposes
1256         // @todo FIXME: We can detect some anons even if it is not loaded. See User::getId()
1257         if ( $wgUser->isItemLoaded( 'id' ) && $wgUser->isAnon() ) {
1258                 $forward .= ' anon';
1259         }
1260         $log = sprintf( "%s\t%04.3f\t%s\n",
1261                 gmdate( 'YmdHis' ), $elapsed,
1262                 urldecode( $wgRequest->getRequestURL() . $forward ) );
1263
1264         wfErrorLog( $log . $profiler->getOutput(), $wgDebugLogFile );
1265 }
1266
1267 /**
1268  * Increment a statistics counter
1269  *
1270  * @param $key String
1271  * @param $count Int
1272  */
1273 function wfIncrStats( $key, $count = 1 ) {
1274         global $wgStatsMethod;
1275
1276         $count = intval( $count );
1277
1278         if( $wgStatsMethod == 'udp' ) {
1279                 global $wgUDPProfilerHost, $wgUDPProfilerPort, $wgDBname, $wgAggregateStatsID;
1280                 static $socket;
1281
1282                 $id = $wgAggregateStatsID !== false ? $wgAggregateStatsID : $wgDBname;
1283
1284                 if ( !$socket ) {
1285                         $socket = socket_create( AF_INET, SOCK_DGRAM, SOL_UDP );
1286                         $statline = "stats/{$id} - 1 1 1 1 1 -total\n";
1287                         socket_sendto(
1288                                 $socket,
1289                                 $statline,
1290                                 strlen( $statline ),
1291                                 0,
1292                                 $wgUDPProfilerHost,
1293                                 $wgUDPProfilerPort
1294                         );
1295                 }
1296                 $statline = "stats/{$id} - {$count} 1 1 1 1 {$key}\n";
1297                 wfSuppressWarnings();
1298                 socket_sendto(
1299                         $socket,
1300                         $statline,
1301                         strlen( $statline ),
1302                         0,
1303                         $wgUDPProfilerHost,
1304                         $wgUDPProfilerPort
1305                 );
1306                 wfRestoreWarnings();
1307         } elseif( $wgStatsMethod == 'cache' ) {
1308                 global $wgMemc;
1309                 $key = wfMemcKey( 'stats', $key );
1310                 if ( is_null( $wgMemc->incr( $key, $count ) ) ) {
1311                         $wgMemc->add( $key, $count );
1312                 }
1313         } else {
1314                 // Disabled
1315         }
1316 }
1317
1318 /**
1319  * Check if the wiki read-only lock file is present. This can be used to lock
1320  * off editing functions, but doesn't guarantee that the database will not be
1321  * modified.
1322  *
1323  * @return bool
1324  */
1325 function wfReadOnly() {
1326         global $wgReadOnlyFile, $wgReadOnly;
1327
1328         if ( !is_null( $wgReadOnly ) ) {
1329                 return (bool)$wgReadOnly;
1330         }
1331         if ( $wgReadOnlyFile == '' ) {
1332                 return false;
1333         }
1334         // Set $wgReadOnly for faster access next time
1335         if ( is_file( $wgReadOnlyFile ) ) {
1336                 $wgReadOnly = file_get_contents( $wgReadOnlyFile );
1337         } else {
1338                 $wgReadOnly = false;
1339         }
1340         return (bool)$wgReadOnly;
1341 }
1342
1343 /**
1344  * @return bool
1345  */
1346 function wfReadOnlyReason() {
1347         global $wgReadOnly;
1348         wfReadOnly();
1349         return $wgReadOnly;
1350 }
1351
1352 /**
1353  * Return a Language object from $langcode
1354  *
1355  * @param $langcode Mixed: either:
1356  *                  - a Language object
1357  *                  - code of the language to get the message for, if it is
1358  *                    a valid code create a language for that language, if
1359  *                    it is a string but not a valid code then make a basic
1360  *                    language object
1361  *                  - a boolean: if it's false then use the global object for
1362  *                    the current user's language (as a fallback for the old parameter
1363  *                    functionality), or if it is true then use global object
1364  *                    for the wiki's content language.
1365  * @return Language object
1366  */
1367 function wfGetLangObj( $langcode = false ) {
1368         # Identify which language to get or create a language object for.
1369         # Using is_object here due to Stub objects.
1370         if( is_object( $langcode ) ) {
1371                 # Great, we already have the object (hopefully)!
1372                 return $langcode;
1373         }
1374
1375         global $wgContLang, $wgLanguageCode;
1376         if( $langcode === true || $langcode === $wgLanguageCode ) {
1377                 # $langcode is the language code of the wikis content language object.
1378                 # or it is a boolean and value is true
1379                 return $wgContLang;
1380         }
1381
1382         global $wgLang;
1383         if( $langcode === false || $langcode === $wgLang->getCode() ) {
1384                 # $langcode is the language code of user language object.
1385                 # or it was a boolean and value is false
1386                 return $wgLang;
1387         }
1388
1389         $validCodes = array_keys( Language::fetchLanguageNames() );
1390         if( in_array( $langcode, $validCodes ) ) {
1391                 # $langcode corresponds to a valid language.
1392                 return Language::factory( $langcode );
1393         }
1394
1395         # $langcode is a string, but not a valid language code; use content language.
1396         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
1397         return $wgContLang;
1398 }
1399
1400 /**
1401  * Old function when $wgBetterDirectionality existed
1402  * All usage removed, wfUILang can be removed in near future
1403  *
1404  * @deprecated since 1.18
1405  * @return Language
1406  */
1407 function wfUILang() {
1408         wfDeprecated( __METHOD__, '1.18' );
1409         global $wgLang;
1410         return $wgLang;
1411 }
1412
1413 /**
1414  * This is the new function for getting translated interface messages.
1415  * See the Message class for documentation how to use them.
1416  * The intention is that this function replaces all old wfMsg* functions.
1417  * @param $key \string Message key.
1418  * Varargs: normal message parameters.
1419  * @return Message
1420  * @since 1.17
1421  */
1422 function wfMessage( $key /*...*/) {
1423         $params = func_get_args();
1424         array_shift( $params );
1425         if ( isset( $params[0] ) && is_array( $params[0] ) ) {
1426                 $params = $params[0];
1427         }
1428         return new Message( $key, $params );
1429 }
1430
1431 /**
1432  * This function accepts multiple message keys and returns a message instance
1433  * for the first message which is non-empty. If all messages are empty then an
1434  * instance of the first message key is returned.
1435  * @param varargs: message keys
1436  * @return Message
1437  * @since 1.18
1438  */
1439 function wfMessageFallback( /*...*/ ) {
1440         $args = func_get_args();
1441         return MWFunction::callArray( 'Message::newFallbackSequence', $args );
1442 }
1443
1444 /**
1445  * Get a message from anywhere, for the current user language.
1446  *
1447  * Use wfMsgForContent() instead if the message should NOT
1448  * change depending on the user preferences.
1449  *
1450  * @param $key String: lookup key for the message, usually
1451  *    defined in languages/Language.php
1452  *
1453  * Parameters to the message, which can be used to insert variable text into
1454  * it, can be passed to this function in the following formats:
1455  * - One per argument, starting at the second parameter
1456  * - As an array in the second parameter
1457  * These are not shown in the function definition.
1458  *
1459  * @return String
1460  */
1461 function wfMsg( $key ) {
1462         $args = func_get_args();
1463         array_shift( $args );
1464         return wfMsgReal( $key, $args );
1465 }
1466
1467 /**
1468  * Same as above except doesn't transform the message
1469  *
1470  * @param $key String
1471  * @return String
1472  */
1473 function wfMsgNoTrans( $key ) {
1474         $args = func_get_args();
1475         array_shift( $args );
1476         return wfMsgReal( $key, $args, true, false, false );
1477 }
1478
1479 /**
1480  * Get a message from anywhere, for the current global language
1481  * set with $wgLanguageCode.
1482  *
1483  * Use this if the message should NOT change dependent on the
1484  * language set in the user's preferences. This is the case for
1485  * most text written into logs, as well as link targets (such as
1486  * the name of the copyright policy page). Link titles, on the
1487  * other hand, should be shown in the UI language.
1488  *
1489  * Note that MediaWiki allows users to change the user interface
1490  * language in their preferences, but a single installation
1491  * typically only contains content in one language.
1492  *
1493  * Be wary of this distinction: If you use wfMsg() where you should
1494  * use wfMsgForContent(), a user of the software may have to
1495  * customize potentially hundreds of messages in
1496  * order to, e.g., fix a link in every possible language.
1497  *
1498  * @param $key String: lookup key for the message, usually
1499  *     defined in languages/Language.php
1500  * @return String
1501  */
1502 function wfMsgForContent( $key ) {
1503         global $wgForceUIMsgAsContentMsg;
1504         $args = func_get_args();
1505         array_shift( $args );
1506         $forcontent = true;
1507         if( is_array( $wgForceUIMsgAsContentMsg ) &&
1508                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
1509         {
1510                 $forcontent = false;
1511         }
1512         return wfMsgReal( $key, $args, true, $forcontent );
1513 }
1514
1515 /**
1516  * Same as above except doesn't transform the message
1517  *
1518  * @param $key String
1519  * @return String
1520  */
1521 function wfMsgForContentNoTrans( $key ) {
1522         global $wgForceUIMsgAsContentMsg;
1523         $args = func_get_args();
1524         array_shift( $args );
1525         $forcontent = true;
1526         if( is_array( $wgForceUIMsgAsContentMsg ) &&
1527                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
1528         {
1529                 $forcontent = false;
1530         }
1531         return wfMsgReal( $key, $args, true, $forcontent, false );
1532 }
1533
1534 /**
1535  * Really get a message
1536  *
1537  * @param $key String: key to get.
1538  * @param $args
1539  * @param $useDB Boolean
1540  * @param $forContent Mixed: Language code, or false for user lang, true for content lang.
1541  * @param $transform Boolean: Whether or not to transform the message.
1542  * @return String: the requested message.
1543  */
1544 function wfMsgReal( $key, $args, $useDB = true, $forContent = false, $transform = true ) {
1545         wfProfileIn( __METHOD__ );
1546         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
1547         $message = wfMsgReplaceArgs( $message, $args );
1548         wfProfileOut( __METHOD__ );
1549         return $message;
1550 }
1551
1552 /**
1553  * Fetch a message string value, but don't replace any keys yet.
1554  *
1555  * @param $key String
1556  * @param $useDB Bool
1557  * @param $langCode String: Code of the language to get the message for, or
1558  *                  behaves as a content language switch if it is a boolean.
1559  * @param $transform Boolean: whether to parse magic words, etc.
1560  * @return string
1561  */
1562 function wfMsgGetKey( $key, $useDB = true, $langCode = false, $transform = true ) {
1563         wfRunHooks( 'NormalizeMessageKey', array( &$key, &$useDB, &$langCode, &$transform ) );
1564
1565         $cache = MessageCache::singleton();
1566         $message = $cache->get( $key, $useDB, $langCode );
1567         if( $message === false ) {
1568                 $message = '&lt;' . htmlspecialchars( $key ) . '&gt;';
1569         } elseif ( $transform ) {
1570                 $message = $cache->transform( $message );
1571         }
1572         return $message;
1573 }
1574
1575 /**
1576  * Replace message parameter keys on the given formatted output.
1577  *
1578  * @param $message String
1579  * @param $args Array
1580  * @return string
1581  * @private
1582  */
1583 function wfMsgReplaceArgs( $message, $args ) {
1584         # Fix windows line-endings
1585         # Some messages are split with explode("\n", $msg)
1586         $message = str_replace( "\r", '', $message );
1587
1588         // Replace arguments
1589         if ( count( $args ) ) {
1590                 if ( is_array( $args[0] ) ) {
1591                         $args = array_values( $args[0] );
1592                 }
1593                 $replacementKeys = array();
1594                 foreach( $args as $n => $param ) {
1595                         $replacementKeys['$' . ( $n + 1 )] = $param;
1596                 }
1597                 $message = strtr( $message, $replacementKeys );
1598         }
1599
1600         return $message;
1601 }
1602
1603 /**
1604  * Return an HTML-escaped version of a message.
1605  * Parameter replacements, if any, are done *after* the HTML-escaping,
1606  * so parameters may contain HTML (eg links or form controls). Be sure
1607  * to pre-escape them if you really do want plaintext, or just wrap
1608  * the whole thing in htmlspecialchars().
1609  *
1610  * @param $key String
1611  * @param string ... parameters
1612  * @return string
1613  */
1614 function wfMsgHtml( $key ) {
1615         $args = func_get_args();
1616         array_shift( $args );
1617         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key ) ), $args );
1618 }
1619
1620 /**
1621  * Return an HTML version of message
1622  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
1623  * so parameters may contain HTML (eg links or form controls). Be sure
1624  * to pre-escape them if you really do want plaintext, or just wrap
1625  * the whole thing in htmlspecialchars().
1626  *
1627  * @param $key String
1628  * @param string ... parameters
1629  * @return string
1630  */
1631 function wfMsgWikiHtml( $key ) {
1632         $args = func_get_args();
1633         array_shift( $args );
1634         return wfMsgReplaceArgs(
1635                 MessageCache::singleton()->parse( wfMsgGetKey( $key ), null,
1636                 /* can't be set to false */ true, /* interface */ true )->getText(),
1637                 $args );
1638 }
1639
1640 /**
1641  * Returns message in the requested format
1642  * @param $key String: key of the message
1643  * @param $options Array: processing rules. Can take the following options:
1644  *   <i>parse</i>: parses wikitext to HTML
1645  *   <i>parseinline</i>: parses wikitext to HTML and removes the surrounding
1646  *       p's added by parser or tidy
1647  *   <i>escape</i>: filters message through htmlspecialchars
1648  *   <i>escapenoentities</i>: same, but allows entity references like &#160; through
1649  *   <i>replaceafter</i>: parameters are substituted after parsing or escaping
1650  *   <i>parsemag</i>: transform the message using magic phrases
1651  *   <i>content</i>: fetch message for content language instead of interface
1652  * Also can accept a single associative argument, of the form 'language' => 'xx':
1653  *   <i>language</i>: Language object or language code to fetch message for
1654  *       (overriden by <i>content</i>).
1655  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
1656  *
1657  * @return String
1658  */
1659 function wfMsgExt( $key, $options ) {
1660         $args = func_get_args();
1661         array_shift( $args );
1662         array_shift( $args );
1663         $options = (array)$options;
1664
1665         foreach( $options as $arrayKey => $option ) {
1666                 if( !preg_match( '/^[0-9]+|language$/', $arrayKey ) ) {
1667                         # An unknown index, neither numeric nor "language"
1668                         wfWarn( "wfMsgExt called with incorrect parameter key $arrayKey", 1, E_USER_WARNING );
1669                 } elseif( preg_match( '/^[0-9]+$/', $arrayKey ) && !in_array( $option,
1670                 array( 'parse', 'parseinline', 'escape', 'escapenoentities',
1671                 'replaceafter', 'parsemag', 'content' ) ) ) {
1672                         # A numeric index with unknown value
1673                         wfWarn( "wfMsgExt called with incorrect parameter $option", 1, E_USER_WARNING );
1674                 }
1675         }
1676
1677         if( in_array( 'content', $options, true ) ) {
1678                 $forContent = true;
1679                 $langCode = true;
1680                 $langCodeObj = null;
1681         } elseif( array_key_exists( 'language', $options ) ) {
1682                 $forContent = false;
1683                 $langCode = wfGetLangObj( $options['language'] );
1684                 $langCodeObj = $langCode;
1685         } else {
1686                 $forContent = false;
1687                 $langCode = false;
1688                 $langCodeObj = null;
1689         }
1690
1691         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
1692
1693         if( !in_array( 'replaceafter', $options, true ) ) {
1694                 $string = wfMsgReplaceArgs( $string, $args );
1695         }
1696
1697         $messageCache = MessageCache::singleton();
1698         $parseInline = in_array( 'parseinline', $options, true );
1699         if( in_array( 'parse', $options, true ) || $parseInline ) {
1700                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj );
1701                 if ( $string instanceof ParserOutput ) {
1702                         $string = $string->getText();
1703                 }
1704
1705                 if ( $parseInline ) {
1706                         $m = array();
1707                         if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
1708                                 $string = $m[1];
1709                         }
1710                 }
1711         } elseif ( in_array( 'parsemag', $options, true ) ) {
1712                 $string = $messageCache->transform( $string,
1713                                 !$forContent, $langCodeObj );
1714         }
1715
1716         if ( in_array( 'escape', $options, true ) ) {
1717                 $string = htmlspecialchars ( $string );
1718         } elseif ( in_array( 'escapenoentities', $options, true ) ) {
1719                 $string = Sanitizer::escapeHtmlAllowEntities( $string );
1720         }
1721
1722         if( in_array( 'replaceafter', $options, true ) ) {
1723                 $string = wfMsgReplaceArgs( $string, $args );
1724         }
1725
1726         return $string;
1727 }
1728
1729 /**
1730  * Since wfMsg() and co suck, they don't return false if the message key they
1731  * looked up didn't exist but a XHTML string, this function checks for the
1732  * nonexistance of messages by checking the MessageCache::get() result directly.
1733  *
1734  * @param $key      String: the message key looked up
1735  * @return Boolean True if the message *doesn't* exist.
1736  */
1737 function wfEmptyMsg( $key ) {
1738         return MessageCache::singleton()->get( $key, /*useDB*/true, /*content*/false ) === false;
1739 }
1740
1741 /**
1742  * Throw a debugging exception. This function previously once exited the process,
1743  * but now throws an exception instead, with similar results.
1744  *
1745  * @param $msg String: message shown when dying.
1746  */
1747 function wfDebugDieBacktrace( $msg = '' ) {
1748         throw new MWException( $msg );
1749 }
1750
1751 /**
1752  * Fetch server name for use in error reporting etc.
1753  * Use real server name if available, so we know which machine
1754  * in a server farm generated the current page.
1755  *
1756  * @return string
1757  */
1758 function wfHostname() {
1759         static $host;
1760         if ( is_null( $host ) ) {
1761                 if ( function_exists( 'posix_uname' ) ) {
1762                         // This function not present on Windows
1763                         $uname = posix_uname();
1764                 } else {
1765                         $uname = false;
1766                 }
1767                 if( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1768                         $host = $uname['nodename'];
1769                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1770                         # Windows computer name
1771                         $host = getenv( 'COMPUTERNAME' );
1772                 } else {
1773                         # This may be a virtual server.
1774                         $host = $_SERVER['SERVER_NAME'];
1775                 }
1776         }
1777         return $host;
1778 }
1779
1780 /**
1781  * Returns a HTML comment with the elapsed time since request.
1782  * This method has no side effects.
1783  *
1784  * @return string
1785  */
1786 function wfReportTime() {
1787         global $wgRequestTime, $wgShowHostnames;
1788
1789         $elapsed = microtime( true ) - $wgRequestTime;
1790
1791         return $wgShowHostnames
1792                 ? sprintf( '<!-- Served by %s in %01.3f secs. -->', wfHostname(), $elapsed )
1793                 : sprintf( '<!-- Served in %01.3f secs. -->', $elapsed );
1794 }
1795
1796 /**
1797  * Safety wrapper for debug_backtrace().
1798  *
1799  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
1800  * murky circumstances, which may be triggered in part by stub objects
1801  * or other fancy talkin'.
1802  *
1803  * Will return an empty array if Zend Optimizer is detected or if
1804  * debug_backtrace is disabled, otherwise the output from
1805  * debug_backtrace() (trimmed).
1806  *
1807  * @param $limit int This parameter can be used to limit the number of stack frames returned
1808  *
1809  * @return array of backtrace information
1810  */
1811 function wfDebugBacktrace( $limit = 0 ) {
1812         static $disabled = null;
1813
1814         if( extension_loaded( 'Zend Optimizer' ) ) {
1815                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
1816                 return array();
1817         }
1818
1819         if ( is_null( $disabled ) ) {
1820                 $disabled = false;
1821                 $functions = explode( ',', ini_get( 'disable_functions' ) );
1822                 $functions = array_map( 'trim', $functions );
1823                 $functions = array_map( 'strtolower', $functions );
1824                 if ( in_array( 'debug_backtrace', $functions ) ) {
1825                         wfDebug( "debug_backtrace is in disabled_functions\n" );
1826                         $disabled = true;
1827                 }
1828         }
1829         if ( $disabled ) {
1830                 return array();
1831         }
1832
1833         if ( $limit && version_compare( PHP_VERSION, '5.4.0', '>=' ) ) {
1834                 return array_slice( debug_backtrace( DEBUG_BACKTRACE_PROVIDE_OBJECT, $limit + 1 ), 1 );
1835         } else {
1836                 return array_slice( debug_backtrace(), 1 );
1837         }
1838 }
1839
1840 /**
1841  * Get a debug backtrace as a string
1842  *
1843  * @return string
1844  */
1845 function wfBacktrace() {
1846         global $wgCommandLineMode;
1847
1848         if ( $wgCommandLineMode ) {
1849                 $msg = '';
1850         } else {
1851                 $msg = "<ul>\n";
1852         }
1853         $backtrace = wfDebugBacktrace();
1854         foreach( $backtrace as $call ) {
1855                 if( isset( $call['file'] ) ) {
1856                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
1857                         $file = $f[count( $f ) - 1];
1858                 } else {
1859                         $file = '-';
1860                 }
1861                 if( isset( $call['line'] ) ) {
1862                         $line = $call['line'];
1863                 } else {
1864                         $line = '-';
1865                 }
1866                 if ( $wgCommandLineMode ) {
1867                         $msg .= "$file line $line calls ";
1868                 } else {
1869                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
1870                 }
1871                 if( !empty( $call['class'] ) ) {
1872                         $msg .= $call['class'] . $call['type'];
1873                 }
1874                 $msg .= $call['function'] . '()';
1875
1876                 if ( $wgCommandLineMode ) {
1877                         $msg .= "\n";
1878                 } else {
1879                         $msg .= "</li>\n";
1880                 }
1881         }
1882         if ( $wgCommandLineMode ) {
1883                 $msg .= "\n";
1884         } else {
1885                 $msg .= "</ul>\n";
1886         }
1887
1888         return $msg;
1889 }
1890
1891 /**
1892  * Get the name of the function which called this function
1893  * wfGetCaller( 1 ) is the function with the wfGetCaller() call (ie. __FUNCTION__)
1894  * wfGetCaller( 2 ) [default] is the caller of the function running wfGetCaller()
1895  * wfGetCaller( 3 ) is the parent of that.
1896  *
1897  * @param $level Int
1898  * @return Bool|string
1899  */
1900 function wfGetCaller( $level = 2 ) {
1901         $backtrace = wfDebugBacktrace( $level + 1 );
1902         if ( isset( $backtrace[$level] ) ) {
1903                 return wfFormatStackFrame( $backtrace[$level] );
1904         } else {
1905                 $caller = 'unknown';
1906         }
1907         return $caller;
1908 }
1909
1910 /**
1911  * Return a string consisting of callers in the stack. Useful sometimes
1912  * for profiling specific points.
1913  *
1914  * @param $limit int The maximum depth of the stack frame to return, or false for
1915  *               the entire stack.
1916  * @return String
1917  */
1918 function wfGetAllCallers( $limit = 3 ) {
1919         $trace = array_reverse( wfDebugBacktrace() );
1920         if ( !$limit || $limit > count( $trace ) - 1 ) {
1921                 $limit = count( $trace ) - 1;
1922         }
1923         $trace = array_slice( $trace, -$limit - 1, $limit );
1924         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1925 }
1926
1927 /**
1928  * Return a string representation of frame
1929  *
1930  * @param $frame Array
1931  * @return Bool
1932  */
1933 function wfFormatStackFrame( $frame ) {
1934         return isset( $frame['class'] ) ?
1935                 $frame['class'] . '::' . $frame['function'] :
1936                 $frame['function'];
1937 }
1938
1939
1940 /* Some generic result counters, pulled out of SearchEngine */
1941
1942
1943 /**
1944  * @todo document
1945  *
1946  * @param $offset Int
1947  * @param $limit Int
1948  * @return String
1949  */
1950 function wfShowingResults( $offset, $limit ) {
1951         global $wgLang;
1952         return wfMsgExt(
1953                 'showingresults',
1954                 array( 'parseinline' ),
1955                 $wgLang->formatNum( $limit ),
1956                 $wgLang->formatNum( $offset + 1 )
1957         );
1958 }
1959
1960 /**
1961  * Generate (prev x| next x) (20|50|100...) type links for paging
1962  *
1963  * @param $offset String
1964  * @param $limit Integer
1965  * @param $link String
1966  * @param $query String: optional URL query parameter string
1967  * @param $atend Bool: optional param for specified if this is the last page
1968  * @return String
1969  * @deprecated in 1.19; use Language::viewPrevNext() instead
1970  */
1971 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
1972         wfDeprecated( __METHOD__, '1.19' );
1973
1974         global $wgLang;
1975
1976         $query = wfCgiToArray( $query );
1977
1978         if( is_object( $link ) ) {
1979                 $title = $link;
1980         } else {
1981                 $title = Title::newFromText( $link );
1982                 if( is_null( $title ) ) {
1983                         return false;
1984                 }
1985         }
1986
1987         return $wgLang->viewPrevNext( $title, $offset, $limit, $query, $atend );
1988 }
1989
1990 /**
1991  * Make a list item, used by various special pages
1992  *
1993  * @param $page String Page link
1994  * @param $details String Text between brackets
1995  * @param $oppositedm Boolean   Add the direction mark opposite to your
1996  *                                                              language, to display text properly
1997  * @return String
1998  * @deprecated since 1.19; use Language::specialList() instead
1999  */
2000 function wfSpecialList( $page, $details, $oppositedm = true ) {
2001         wfDeprecated( __METHOD__, '1.19' );
2002
2003         global $wgLang;
2004         return $wgLang->specialList( $page, $details, $oppositedm );
2005 }
2006
2007 /**
2008  * @todo document
2009  * @todo FIXME: We may want to blacklist some broken browsers
2010  *
2011  * @param $force Bool
2012  * @return bool Whereas client accept gzip compression
2013  */
2014 function wfClientAcceptsGzip( $force = false ) {
2015         static $result = null;
2016         if ( $result === null || $force ) {
2017                 $result = false;
2018                 if( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
2019                         # @todo FIXME: We may want to blacklist some broken browsers
2020                         $m = array();
2021                         if( preg_match(
2022                                 '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
2023                                 $_SERVER['HTTP_ACCEPT_ENCODING'],
2024                                 $m )
2025                         )
2026                         {
2027                                 if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
2028                                         $result = false;
2029                                         return $result;
2030                                 }
2031                                 wfDebug( "wfClientAcceptsGzip: client accepts gzip.\n" );
2032                                 $result = true;
2033                         }
2034                 }
2035         }
2036         return $result;
2037 }
2038
2039 /**
2040  * Obtain the offset and limit values from the request string;
2041  * used in special pages
2042  *
2043  * @param $deflimit Int default limit if none supplied
2044  * @param $optionname String Name of a user preference to check against
2045  * @return array
2046  *
2047  */
2048 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
2049         global $wgRequest;
2050         return $wgRequest->getLimitOffset( $deflimit, $optionname );
2051 }
2052
2053 /**
2054  * Escapes the given text so that it may be output using addWikiText()
2055  * without any linking, formatting, etc. making its way through. This
2056  * is achieved by substituting certain characters with HTML entities.
2057  * As required by the callers, <nowiki> is not used.
2058  *
2059  * @param $text String: text to be escaped
2060  * @return String
2061  */
2062 function wfEscapeWikiText( $text ) {
2063         $text = strtr( "\n$text", array(
2064                 '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
2065                 '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
2066                 '{' => '&#123;', '|' => '&#124;', '}' => '&#125;',
2067                 "\n#" => "\n&#35;", "\n*" => "\n&#42;",
2068                 "\n:" => "\n&#58;", "\n;" => "\n&#59;",
2069                 '://' => '&#58;//', 'ISBN ' => 'ISBN&#32;', 'RFC ' => 'RFC&#32;',
2070         ) );
2071         return substr( $text, 1 );
2072 }
2073
2074 /**
2075  * Get the current unix timetstamp with microseconds.  Useful for profiling
2076  * @return Float
2077  */
2078 function wfTime() {
2079         return microtime( true );
2080 }
2081
2082 /**
2083  * Sets dest to source and returns the original value of dest
2084  * If source is NULL, it just returns the value, it doesn't set the variable
2085  * If force is true, it will set the value even if source is NULL
2086  *
2087  * @param $dest Mixed
2088  * @param $source Mixed
2089  * @param $force Bool
2090  * @return Mixed
2091  */
2092 function wfSetVar( &$dest, $source, $force = false ) {
2093         $temp = $dest;
2094         if ( !is_null( $source ) || $force ) {
2095                 $dest = $source;
2096         }
2097         return $temp;
2098 }
2099
2100 /**
2101  * As for wfSetVar except setting a bit
2102  *
2103  * @param $dest Int
2104  * @param $bit Int
2105  * @param $state Bool
2106  *
2107  * @return bool
2108  */
2109 function wfSetBit( &$dest, $bit, $state = true ) {
2110         $temp = (bool)( $dest & $bit );
2111         if ( !is_null( $state ) ) {
2112                 if ( $state ) {
2113                         $dest |= $bit;
2114                 } else {
2115                         $dest &= ~$bit;
2116                 }
2117         }
2118         return $temp;
2119 }
2120
2121 /**
2122  * A wrapper around the PHP function var_export().
2123  * Either print it or add it to the regular output ($wgOut).
2124  *
2125  * @param $var mixed A PHP variable to dump.
2126  */
2127 function wfVarDump( $var ) {
2128         global $wgOut;
2129         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
2130         if ( headers_sent() || !isset( $wgOut ) || !is_object( $wgOut ) ) {
2131                 print $s;
2132         } else {
2133                 $wgOut->addHTML( $s );
2134         }
2135 }
2136
2137 /**
2138  * Provide a simple HTTP error.
2139  *
2140  * @param $code Int|String
2141  * @param $label String
2142  * @param $desc String
2143  */
2144 function wfHttpError( $code, $label, $desc ) {
2145         global $wgOut;
2146         $wgOut->disable();
2147         header( "HTTP/1.0 $code $label" );
2148         header( "Status: $code $label" );
2149         $wgOut->sendCacheControl();
2150
2151         header( 'Content-type: text/html; charset=utf-8' );
2152         print "<!doctype html>" .
2153                 '<html><head><title>' .
2154                 htmlspecialchars( $label ) .
2155                 '</title></head><body><h1>' .
2156                 htmlspecialchars( $label ) .
2157                 '</h1><p>' .
2158                 nl2br( htmlspecialchars( $desc ) ) .
2159                 "</p></body></html>\n";
2160 }
2161
2162 /**
2163  * Clear away any user-level output buffers, discarding contents.
2164  *
2165  * Suitable for 'starting afresh', for instance when streaming
2166  * relatively large amounts of data without buffering, or wanting to
2167  * output image files without ob_gzhandler's compression.
2168  *
2169  * The optional $resetGzipEncoding parameter controls suppression of
2170  * the Content-Encoding header sent by ob_gzhandler; by default it
2171  * is left. See comments for wfClearOutputBuffers() for why it would
2172  * be used.
2173  *
2174  * Note that some PHP configuration options may add output buffer
2175  * layers which cannot be removed; these are left in place.
2176  *
2177  * @param $resetGzipEncoding Bool
2178  */
2179 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
2180         if( $resetGzipEncoding ) {
2181                 // Suppress Content-Encoding and Content-Length
2182                 // headers from 1.10+s wfOutputHandler
2183                 global $wgDisableOutputCompression;
2184                 $wgDisableOutputCompression = true;
2185         }
2186         while( $status = ob_get_status() ) {
2187                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
2188                         // Probably from zlib.output_compression or other
2189                         // PHP-internal setting which can't be removed.
2190                         //
2191                         // Give up, and hope the result doesn't break
2192                         // output behavior.
2193                         break;
2194                 }
2195                 if( !ob_end_clean() ) {
2196                         // Could not remove output buffer handler; abort now
2197                         // to avoid getting in some kind of infinite loop.
2198                         break;
2199                 }
2200                 if( $resetGzipEncoding ) {
2201                         if( $status['name'] == 'ob_gzhandler' ) {
2202                                 // Reset the 'Content-Encoding' field set by this handler
2203                                 // so we can start fresh.
2204                                 header_remove( 'Content-Encoding' );
2205                                 break;
2206                         }
2207                 }
2208         }
2209 }
2210
2211 /**
2212  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
2213  *
2214  * Clear away output buffers, but keep the Content-Encoding header
2215  * produced by ob_gzhandler, if any.
2216  *
2217  * This should be used for HTTP 304 responses, where you need to
2218  * preserve the Content-Encoding header of the real result, but
2219  * also need to suppress the output of ob_gzhandler to keep to spec
2220  * and avoid breaking Firefox in rare cases where the headers and
2221  * body are broken over two packets.
2222  */
2223 function wfClearOutputBuffers() {
2224         wfResetOutputBuffers( false );
2225 }
2226
2227 /**
2228  * Converts an Accept-* header into an array mapping string values to quality
2229  * factors
2230  *
2231  * @param $accept String
2232  * @param $def String default
2233  * @return Array
2234  */
2235 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
2236         # No arg means accept anything (per HTTP spec)
2237         if( !$accept ) {
2238                 return array( $def => 1.0 );
2239         }
2240
2241         $prefs = array();
2242
2243         $parts = explode( ',', $accept );
2244
2245         foreach( $parts as $part ) {
2246                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
2247                 $values = explode( ';', trim( $part ) );
2248                 $match = array();
2249                 if ( count( $values ) == 1 ) {
2250                         $prefs[$values[0]] = 1.0;
2251                 } elseif ( preg_match( '/q\s*=\s*(\d*\.\d+)/', $values[1], $match ) ) {
2252                         $prefs[$values[0]] = floatval( $match[1] );
2253                 }
2254         }
2255
2256         return $prefs;
2257 }
2258
2259 /**
2260  * Checks if a given MIME type matches any of the keys in the given
2261  * array. Basic wildcards are accepted in the array keys.
2262  *
2263  * Returns the matching MIME type (or wildcard) if a match, otherwise
2264  * NULL if no match.
2265  *
2266  * @param $type String
2267  * @param $avail Array
2268  * @return string
2269  * @private
2270  */
2271 function mimeTypeMatch( $type, $avail ) {
2272         if( array_key_exists( $type, $avail ) ) {
2273                 return $type;
2274         } else {
2275                 $parts = explode( '/', $type );
2276                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
2277                         return $parts[0] . '/*';
2278                 } elseif( array_key_exists( '*/*', $avail ) ) {
2279                         return '*/*';
2280                 } else {
2281                         return null;
2282                 }
2283         }
2284 }
2285
2286 /**
2287  * Returns the 'best' match between a client's requested internet media types
2288  * and the server's list of available types. Each list should be an associative
2289  * array of type to preference (preference is a float between 0.0 and 1.0).
2290  * Wildcards in the types are acceptable.
2291  *
2292  * @param $cprefs Array: client's acceptable type list
2293  * @param $sprefs Array: server's offered types
2294  * @return string
2295  *
2296  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
2297  * XXX: generalize to negotiate other stuff
2298  */
2299 function wfNegotiateType( $cprefs, $sprefs ) {
2300         $combine = array();
2301
2302         foreach( array_keys( $sprefs ) as $type ) {
2303                 $parts = explode( '/', $type );
2304                 if( $parts[1] != '*' ) {
2305                         $ckey = mimeTypeMatch( $type, $cprefs );
2306                         if( $ckey ) {
2307                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
2308                         }
2309                 }
2310         }
2311
2312         foreach( array_keys( $cprefs ) as $type ) {
2313                 $parts = explode( '/', $type );
2314                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
2315                         $skey = mimeTypeMatch( $type, $sprefs );
2316                         if( $skey ) {
2317                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
2318                         }
2319                 }
2320         }
2321
2322         $bestq = 0;
2323         $besttype = null;
2324
2325         foreach( array_keys( $combine ) as $type ) {
2326                 if( $combine[$type] > $bestq ) {
2327                         $besttype = $type;
2328                         $bestq = $combine[$type];
2329                 }
2330         }
2331
2332         return $besttype;
2333 }
2334
2335 /**
2336  * Reference-counted warning suppression
2337  *
2338  * @param $end Bool
2339  */
2340 function wfSuppressWarnings( $end = false ) {
2341         static $suppressCount = 0;
2342         static $originalLevel = false;
2343
2344         if ( $end ) {
2345                 if ( $suppressCount ) {
2346                         --$suppressCount;
2347                         if ( !$suppressCount ) {
2348                                 error_reporting( $originalLevel );
2349                         }
2350                 }
2351         } else {
2352                 if ( !$suppressCount ) {
2353                         // E_DEPRECATED is undefined in PHP 5.2
2354                         if( !defined( 'E_DEPRECATED' ) ) {
2355                                 define( 'E_DEPRECATED', 8192 );
2356                         }
2357                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE | E_USER_WARNING | E_USER_NOTICE | E_DEPRECATED ) );
2358                 }
2359                 ++$suppressCount;
2360         }
2361 }
2362
2363 /**
2364  * Restore error level to previous value
2365  */
2366 function wfRestoreWarnings() {
2367         wfSuppressWarnings( true );
2368 }
2369
2370 # Autodetect, convert and provide timestamps of various types
2371
2372 /**
2373  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
2374  */
2375 define( 'TS_UNIX', 0 );
2376
2377 /**
2378  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
2379  */
2380 define( 'TS_MW', 1 );
2381
2382 /**
2383  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
2384  */
2385 define( 'TS_DB', 2 );
2386
2387 /**
2388  * RFC 2822 format, for E-mail and HTTP headers
2389  */
2390 define( 'TS_RFC2822', 3 );
2391
2392 /**
2393  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
2394  *
2395  * This is used by Special:Export
2396  */
2397 define( 'TS_ISO_8601', 4 );
2398
2399 /**
2400  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
2401  *
2402  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
2403  *       DateTime tag and page 36 for the DateTimeOriginal and
2404  *       DateTimeDigitized tags.
2405  */
2406 define( 'TS_EXIF', 5 );
2407
2408 /**
2409  * Oracle format time.
2410  */
2411 define( 'TS_ORACLE', 6 );
2412
2413 /**
2414  * Postgres format time.
2415  */
2416 define( 'TS_POSTGRES', 7 );
2417
2418 /**
2419  * DB2 format time
2420  */
2421 define( 'TS_DB2', 8 );
2422
2423 /**
2424  * ISO 8601 basic format with no timezone: 19860209T200000Z.  This is used by ResourceLoader
2425  */
2426 define( 'TS_ISO_8601_BASIC', 9 );
2427
2428 /**
2429  * Get a timestamp string in one of various formats
2430  *
2431  * @param $outputtype Mixed: A timestamp in one of the supported formats, the
2432  *                    function will autodetect which format is supplied and act
2433  *                    accordingly.
2434  * @param $ts Mixed: the timestamp to convert or 0 for the current timestamp
2435  * @return Mixed: String / false The same date in the format specified in $outputtype or false
2436  */
2437 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
2438         $uts = 0;
2439         $da = array();
2440         $strtime = '';
2441
2442         if ( !$ts ) { // We want to catch 0, '', null... but not date strings starting with a letter.
2443                 $uts = time();
2444                 $strtime = "@$uts";
2445         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2446                 # TS_DB
2447         } elseif ( preg_match( '/^(\d{4}):(\d\d):(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2448                 # TS_EXIF
2449         } elseif ( preg_match( '/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/D', $ts, $da ) ) {
2450                 # TS_MW
2451         } elseif ( preg_match( '/^-?\d{1,13}$/D', $ts ) ) {
2452                 # TS_UNIX
2453                 $uts = $ts;
2454                 $strtime = "@$ts"; // http://php.net/manual/en/datetime.formats.compound.php
2455         } elseif ( preg_match( '/^\d{2}-\d{2}-\d{4} \d{2}:\d{2}:\d{2}.\d{6}$/', $ts ) ) {
2456                 # TS_ORACLE // session altered to DD-MM-YYYY HH24:MI:SS.FF6
2457                 $strtime = preg_replace( '/(\d\d)\.(\d\d)\.(\d\d)(\.(\d+))?/', "$1:$2:$3",
2458                                 str_replace( '+00:00', 'UTC', $ts ) );
2459         } elseif ( preg_match( '/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2460                 # TS_ISO_8601
2461         } elseif ( preg_match( '/^(\d{4})(\d{2})(\d{2})T(\d{2})(\d{2})(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2462                 #TS_ISO_8601_BASIC
2463         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d*[\+\- ](\d\d)$/', $ts, $da ) ) {
2464                 # TS_POSTGRES
2465         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d* GMT$/', $ts, $da ) ) {
2466                 # TS_POSTGRES
2467         } elseif (preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.\d\d\d$/', $ts, $da ) ) {
2468                 # TS_DB2
2469         } elseif ( preg_match( '/^[ \t\r\n]*([A-Z][a-z]{2},[ \t\r\n]*)?' . # Day of week
2470                                                         '\d\d?[ \t\r\n]*[A-Z][a-z]{2}[ \t\r\n]*\d{2}(?:\d{2})?' .  # dd Mon yyyy
2471                                                         '[ \t\r\n]*\d\d[ \t\r\n]*:[ \t\r\n]*\d\d[ \t\r\n]*:[ \t\r\n]*\d\d/S', $ts ) ) { # hh:mm:ss
2472                 # TS_RFC2822, accepting a trailing comment. See http://www.squid-cache.org/mail-archive/squid-users/200307/0122.html / r77171
2473                 # The regex is a superset of rfc2822 for readability
2474                 $strtime = strtok( $ts, ';' );
2475         } elseif ( preg_match( '/^[A-Z][a-z]{5,8}, \d\d-[A-Z][a-z]{2}-\d{2} \d\d:\d\d:\d\d/', $ts ) ) {
2476                 # TS_RFC850
2477                 $strtime = $ts;
2478         } elseif ( preg_match( '/^[A-Z][a-z]{2} [A-Z][a-z]{2} +\d{1,2} \d\d:\d\d:\d\d \d{4}/', $ts ) ) {
2479                 # asctime
2480                 $strtime = $ts;
2481         } else {
2482                 # Bogus value...
2483                 wfDebug("wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n");
2484
2485                 return false;
2486         }
2487
2488         static $formats = array(
2489                 TS_UNIX => 'U',
2490                 TS_MW => 'YmdHis',
2491                 TS_DB => 'Y-m-d H:i:s',
2492                 TS_ISO_8601 => 'Y-m-d\TH:i:s\Z',
2493                 TS_ISO_8601_BASIC => 'Ymd\THis\Z',
2494                 TS_EXIF => 'Y:m:d H:i:s', // This shouldn't ever be used, but is included for completeness
2495                 TS_RFC2822 => 'D, d M Y H:i:s',
2496                 TS_ORACLE => 'd-m-Y H:i:s.000000', // Was 'd-M-y h.i.s A' . ' +00:00' before r51500
2497                 TS_POSTGRES => 'Y-m-d H:i:s',
2498                 TS_DB2 => 'Y-m-d H:i:s',
2499         );
2500
2501         if ( !isset( $formats[$outputtype] ) ) {
2502                 throw new MWException( 'wfTimestamp() called with illegal output type.' );
2503         }
2504
2505         if ( function_exists( "date_create" ) ) {
2506                 if ( count( $da ) ) {
2507                         $ds = sprintf("%04d-%02d-%02dT%02d:%02d:%02d.00+00:00",
2508                                 (int)$da[1], (int)$da[2], (int)$da[3],
2509                                 (int)$da[4], (int)$da[5], (int)$da[6]);
2510
2511                         $d = date_create( $ds, new DateTimeZone( 'GMT' ) );
2512                 } elseif ( $strtime ) {
2513                         $d = date_create( $strtime, new DateTimeZone( 'GMT' ) );
2514                 } else {
2515                         return false;
2516                 }
2517
2518                 if ( !$d ) {
2519                         wfDebug("wfTimestamp() fed bogus time value: $outputtype; $ts\n");
2520                         return false;
2521                 }
2522
2523                 $output = $d->format( $formats[$outputtype] );
2524         } else {
2525                 if ( count( $da ) ) {
2526                         // Warning! gmmktime() acts oddly if the month or day is set to 0
2527                         // We may want to handle that explicitly at some point
2528                         $uts = gmmktime( (int)$da[4], (int)$da[5], (int)$da[6],
2529                                 (int)$da[2], (int)$da[3], (int)$da[1] );
2530                 } elseif ( $strtime ) {
2531                         $uts = strtotime( $strtime );
2532                 }
2533
2534                 if ( $uts === false ) {
2535                         wfDebug("wfTimestamp() can't parse the timestamp (non 32-bit time? Update php): $outputtype; $ts\n");
2536                         return false;
2537                 }
2538
2539                 if ( TS_UNIX == $outputtype ) {
2540                         return $uts;
2541                 }
2542                 $output = gmdate( $formats[$outputtype], $uts );
2543         }
2544
2545         if ( ( $outputtype == TS_RFC2822 ) || ( $outputtype == TS_POSTGRES ) ) {
2546                 $output .= ' GMT';
2547         }
2548
2549         return $output;
2550 }
2551
2552 /**
2553  * Return a formatted timestamp, or null if input is null.
2554  * For dealing with nullable timestamp columns in the database.
2555  *
2556  * @param $outputtype Integer
2557  * @param $ts String
2558  * @return String
2559  */
2560 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2561         if( is_null( $ts ) ) {
2562                 return null;
2563         } else {
2564                 return wfTimestamp( $outputtype, $ts );
2565         }
2566 }
2567
2568 /**
2569  * Convenience function; returns MediaWiki timestamp for the present time.
2570  *
2571  * @return string
2572  */
2573 function wfTimestampNow() {
2574         # return NOW
2575         return wfTimestamp( TS_MW, time() );
2576 }
2577
2578 /**
2579  * Check if the operating system is Windows
2580  *
2581  * @return Bool: true if it's Windows, False otherwise.
2582  */
2583 function wfIsWindows() {
2584         static $isWindows = null;
2585         if ( $isWindows === null ) {
2586                 $isWindows = substr( php_uname(), 0, 7 ) == 'Windows';
2587         }
2588         return $isWindows;
2589 }
2590
2591 /**
2592  * Check if we are running under HipHop
2593  *
2594  * @return Bool
2595  */
2596 function wfIsHipHop() {
2597         return function_exists( 'hphp_thread_set_warmup_enabled' );
2598 }
2599
2600 /**
2601  * Swap two variables
2602  *
2603  * @param $x Mixed
2604  * @param $y Mixed
2605  */
2606 function swap( &$x, &$y ) {
2607         $z = $x;
2608         $x = $y;
2609         $y = $z;
2610 }
2611
2612 /**
2613  * Tries to get the system directory for temporary files. First
2614  * $wgTmpDirectory is checked, and then the TMPDIR, TMP, and TEMP
2615  * environment variables are then checked in sequence, and if none are
2616  * set try sys_get_temp_dir().
2617  *
2618  * NOTE: When possible, use instead the tmpfile() function to create
2619  * temporary files to avoid race conditions on file creation, etc.
2620  *
2621  * @return String
2622  */
2623 function wfTempDir() {
2624         global $wgTmpDirectory;
2625
2626         if ( $wgTmpDirectory !== false ) {
2627                 return $wgTmpDirectory;
2628         }
2629
2630         $tmpDir = array_map( "getenv", array( 'TMPDIR', 'TMP', 'TEMP' ) );
2631
2632         foreach( $tmpDir as $tmp ) {
2633                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
2634                         return $tmp;
2635                 }
2636         }
2637         return sys_get_temp_dir();
2638 }
2639
2640 /**
2641  * Make directory, and make all parent directories if they don't exist
2642  *
2643  * @param $dir String: full path to directory to create
2644  * @param $mode Integer: chmod value to use, default is $wgDirectoryMode
2645  * @param $caller String: optional caller param for debugging.
2646  * @return bool
2647  */
2648 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2649         global $wgDirectoryMode;
2650
2651         if ( FileBackend::isStoragePath( $dir ) ) { // sanity
2652                 throw new MWException( __FUNCTION__ . " given storage path `$dir`.");
2653         }
2654
2655         if ( !is_null( $caller ) ) {
2656                 wfDebug( "$caller: called wfMkdirParents($dir)\n" );
2657         }
2658
2659         if( strval( $dir ) === '' || file_exists( $dir ) ) {
2660                 return true;
2661         }
2662
2663         $dir = str_replace( array( '\\', '/' ), DIRECTORY_SEPARATOR, $dir );
2664
2665         if ( is_null( $mode ) ) {
2666                 $mode = $wgDirectoryMode;
2667         }
2668
2669         // Turn off the normal warning, we're doing our own below
2670         wfSuppressWarnings();
2671         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2672         wfRestoreWarnings();
2673
2674         if( !$ok ) {
2675                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2676                 trigger_error( sprintf( "%s: failed to mkdir \"%s\" mode 0%o", __FUNCTION__, $dir, $mode ),
2677                         E_USER_WARNING );
2678         }
2679         return $ok;
2680 }
2681
2682 /**
2683  * Remove a directory and all its content.
2684  * Does not hide error.
2685  */
2686 function wfRecursiveRemoveDir( $dir ) {
2687         wfDebug( __FUNCTION__ . "( $dir )\n" );
2688         // taken from http://de3.php.net/manual/en/function.rmdir.php#98622
2689         if ( is_dir( $dir ) ) {
2690                 $objects = scandir( $dir );
2691                 foreach ( $objects as $object ) {
2692                         if ( $object != "." && $object != ".." ) {
2693                                 if ( filetype( $dir . '/' . $object ) == "dir" ) {
2694                                         wfRecursiveRemoveDir( $dir . '/' . $object );
2695                                 } else {
2696                                         unlink( $dir . '/' . $object );
2697                                 }
2698                         }
2699                 }
2700                 reset( $objects );
2701                 rmdir( $dir );
2702         }
2703 }
2704
2705 /**
2706  * @param $nr Mixed: the number to format
2707  * @param $acc Integer: the number of digits after the decimal point, default 2
2708  * @param $round Boolean: whether or not to round the value, default true
2709  * @return float
2710  */
2711 function wfPercent( $nr, $acc = 2, $round = true ) {
2712         $ret = sprintf( "%.${acc}f", $nr );
2713         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2714 }
2715
2716 /**
2717  * Find out whether or not a mixed variable exists in a string
2718  *
2719  * @param $needle String
2720  * @param $str String
2721  * @param $insensitive Boolean
2722  * @return Boolean
2723  */
2724 function in_string( $needle, $str, $insensitive = false ) {
2725         $func = 'strpos';
2726         if( $insensitive ) $func = 'stripos';
2727
2728         return $func( $str, $needle ) !== false;
2729 }
2730
2731 /**
2732  * Safety wrapper around ini_get() for boolean settings.
2733  * The values returned from ini_get() are pre-normalized for settings
2734  * set via php.ini or php_flag/php_admin_flag... but *not*
2735  * for those set via php_value/php_admin_value.
2736  *
2737  * It's fairly common for people to use php_value instead of php_flag,
2738  * which can leave you with an 'off' setting giving a false positive
2739  * for code that just takes the ini_get() return value as a boolean.
2740  *
2741  * To make things extra interesting, setting via php_value accepts
2742  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2743  * Unrecognized values go false... again opposite PHP's own coercion
2744  * from string to bool.
2745  *
2746  * Luckily, 'properly' set settings will always come back as '0' or '1',
2747  * so we only have to worry about them and the 'improper' settings.
2748  *
2749  * I frickin' hate PHP... :P
2750  *
2751  * @param $setting String
2752  * @return Bool
2753  */
2754 function wfIniGetBool( $setting ) {
2755         $val = ini_get( $setting );
2756         // 'on' and 'true' can't have whitespace around them, but '1' can.
2757         return strtolower( $val ) == 'on'
2758                 || strtolower( $val ) == 'true'
2759                 || strtolower( $val ) == 'yes'
2760                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2761 }
2762
2763 /**
2764  * Wrapper function for PHP's dl(). This doesn't work in most situations from
2765  * PHP 5.3 onward, and is usually disabled in shared environments anyway.
2766  *
2767  * @param $extension String A PHP extension. The file suffix (.so or .dll)
2768  *                          should be omitted
2769  * @param $fileName String Name of the library, if not $extension.suffix
2770  * @return Bool - Whether or not the extension is loaded
2771  */
2772 function wfDl( $extension, $fileName = null ) {
2773         if( extension_loaded( $extension ) ) {
2774                 return true;
2775         }
2776
2777         $canDl = false;
2778         $sapi = php_sapi_name();
2779         if( $sapi == 'cli' || $sapi == 'cgi' || $sapi == 'embed' ) {
2780                 $canDl = ( function_exists( 'dl' ) && is_callable( 'dl' )
2781                 && wfIniGetBool( 'enable_dl' ) && !wfIniGetBool( 'safe_mode' ) );
2782         }
2783
2784         if( $canDl ) {
2785                 $fileName = $fileName ? $fileName : $extension;
2786                 if( wfIsWindows() ) {
2787                         $fileName = 'php_' . $fileName;
2788                 }
2789                 wfSuppressWarnings();
2790                 dl( $fileName . '.' . PHP_SHLIB_SUFFIX );
2791                 wfRestoreWarnings();
2792         }
2793         return extension_loaded( $extension );
2794 }
2795
2796 /**
2797  * Windows-compatible version of escapeshellarg()
2798  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
2799  * function puts single quotes in regardless of OS.
2800  *
2801  * Also fixes the locale problems on Linux in PHP 5.2.6+ (bug backported to
2802  * earlier distro releases of PHP)
2803  *
2804  * @param varargs
2805  * @return String
2806  */
2807 function wfEscapeShellArg( ) {
2808         wfInitShellLocale();
2809
2810         $args = func_get_args();
2811         $first = true;
2812         $retVal = '';
2813         foreach ( $args as $arg ) {
2814                 if ( !$first ) {
2815                         $retVal .= ' ';
2816                 } else {
2817                         $first = false;
2818                 }
2819
2820                 if ( wfIsWindows() ) {
2821                         // Escaping for an MSVC-style command line parser and CMD.EXE
2822                         // Refs:
2823                         //  * http://web.archive.org/web/20020708081031/http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
2824                         //  * http://technet.microsoft.com/en-us/library/cc723564.aspx
2825                         //  * Bug #13518
2826                         //  * CR r63214
2827                         // Double the backslashes before any double quotes. Escape the double quotes.
2828                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
2829                         $arg = '';
2830                         $iteration = 0;
2831                         foreach ( $tokens as $token ) {
2832                                 if ( $iteration % 2 == 1 ) {
2833                                         // Delimiter, a double quote preceded by zero or more slashes
2834                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
2835                                 } elseif ( $iteration % 4 == 2 ) {
2836                                         // ^ in $token will be outside quotes, need to be escaped
2837                                         $arg .= str_replace( '^', '^^', $token );
2838                                 } else { // $iteration % 4 == 0
2839                                         // ^ in $token will appear inside double quotes, so leave as is
2840                                         $arg .= $token;
2841                                 }
2842                                 $iteration++;
2843                         }
2844                         // Double the backslashes before the end of the string, because
2845                         // we will soon add a quote
2846                         $m = array();
2847                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
2848                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
2849                         }
2850
2851                         // Add surrounding quotes
2852                         $retVal .= '"' . $arg . '"';
2853                 } else {
2854                         $retVal .= escapeshellarg( $arg );
2855                 }
2856         }
2857         return $retVal;
2858 }
2859
2860 /**
2861  * Execute a shell command, with time and memory limits mirrored from the PHP
2862  * configuration if supported.
2863  * @param $cmd String Command line, properly escaped for shell.
2864  * @param &$retval null|Mixed optional, will receive the program's exit code.
2865  *                 (non-zero is usually failure)
2866  * @param $environ Array optional environment variables which should be
2867  *                 added to the executed command environment.
2868  * @return string collected stdout as a string (trailing newlines stripped)
2869  */
2870 function wfShellExec( $cmd, &$retval = null, $environ = array() ) {
2871         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize, $wgMaxShellTime;
2872
2873         static $disabled;
2874         if ( is_null( $disabled ) ) {
2875                 $disabled = false;
2876                 if( wfIniGetBool( 'safe_mode' ) ) {
2877                         wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
2878                         $disabled = 'safemode';
2879                 } else {
2880                         $functions = explode( ',', ini_get( 'disable_functions' ) );
2881                         $functions = array_map( 'trim', $functions );
2882                         $functions = array_map( 'strtolower', $functions );
2883                         if ( in_array( 'passthru', $functions ) ) {
2884                                 wfDebug( "passthru is in disabled_functions\n" );
2885                                 $disabled = 'passthru';
2886                         }
2887                 }
2888         }
2889         if ( $disabled ) {
2890                 $retval = 1;
2891                 return $disabled == 'safemode' ?
2892                         'Unable to run external programs in safe mode.' :
2893                         'Unable to run external programs, passthru() is disabled.';
2894         }
2895
2896         wfInitShellLocale();
2897
2898         $envcmd = '';
2899         foreach( $environ as $k => $v ) {
2900                 if ( wfIsWindows() ) {
2901                         /* Surrounding a set in quotes (method used by wfEscapeShellArg) makes the quotes themselves
2902                          * appear in the environment variable, so we must use carat escaping as documented in
2903                          * http://technet.microsoft.com/en-us/library/cc723564.aspx
2904                          * Note however that the quote isn't listed there, but is needed, and the parentheses
2905                          * are listed there but doesn't appear to need it.
2906                          */
2907                         $envcmd .= "set $k=" . preg_replace( '/([&|()<>^"])/', '^\\1', $v ) . '&& ';
2908                 } else {
2909                         /* Assume this is a POSIX shell, thus required to accept variable assignments before the command
2910                          * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_09_01
2911                          */
2912                         $envcmd .= "$k=" . escapeshellarg( $v ) . ' ';
2913                 }
2914         }
2915         $cmd = $envcmd . $cmd;
2916
2917         if ( php_uname( 's' ) == 'Linux' ) {
2918                 $time = intval( $wgMaxShellTime );
2919                 $mem = intval( $wgMaxShellMemory );
2920                 $filesize = intval( $wgMaxShellFileSize );
2921
2922                 if ( $time > 0 && $mem > 0 ) {
2923                         $script = "$IP/bin/ulimit4.sh";
2924                         if ( is_executable( $script ) ) {
2925                                 $cmd = '/bin/bash ' . escapeshellarg( $script ) . " $time $mem $filesize " . escapeshellarg( $cmd );
2926                         }
2927                 }
2928         }
2929         wfDebug( "wfShellExec: $cmd\n" );
2930
2931         $retval = 1; // error by default?
2932         ob_start();
2933         passthru( $cmd, $retval );
2934         $output = ob_get_contents();
2935         ob_end_clean();
2936
2937         if ( $retval == 127 ) {
2938                 wfDebugLog( 'exec', "Possibly missing executable file: $cmd\n" );
2939         }
2940         return $output;
2941 }
2942
2943 /**
2944  * Workaround for http://bugs.php.net/bug.php?id=45132
2945  * escapeshellarg() destroys non-ASCII characters if LANG is not a UTF-8 locale
2946  */
2947 function wfInitShellLocale() {
2948         static $done = false;
2949         if ( $done ) {
2950                 return;
2951         }
2952         $done = true;
2953         global $wgShellLocale;
2954         if ( !wfIniGetBool( 'safe_mode' ) ) {
2955                 putenv( "LC_CTYPE=$wgShellLocale" );
2956                 setlocale( LC_CTYPE, $wgShellLocale );
2957         }
2958 }
2959
2960 /**
2961  * Alias to wfShellWikiCmd()
2962  * @see wfShellWikiCmd()
2963  */
2964 function wfShellMaintenanceCmd( $script, array $parameters = array(), array $options = array() ) {
2965         return wfShellWikiCmd( $script, $parameters, $options );
2966 }
2967
2968 /**
2969  * Generate a shell-escaped command line string to run a MediaWiki cli script.
2970  * Note that $parameters should be a flat array and an option with an argument
2971  * should consist of two consecutive items in the array (do not use "--option value").
2972  * @param $script string MediaWiki cli script path
2973  * @param $parameters Array Arguments and options to the script
2974  * @param $options Array Associative array of options:
2975  *              'php': The path to the php executable
2976  *              'wrapper': Path to a PHP wrapper to handle the maintenance script
2977  * @return Array
2978  */
2979 function wfShellWikiCmd( $script, array $parameters = array(), array $options = array() ) {
2980         global $wgPhpCli;
2981         // Give site config file a chance to run the script in a wrapper.
2982         // The caller may likely want to call wfBasename() on $script.
2983         wfRunHooks( 'wfShellWikiCmd', array( &$script, &$parameters, &$options ) );
2984         $cmd = isset( $options['php'] ) ? array( $options['php'] ) : array( $wgPhpCli );
2985         if ( isset( $options['wrapper'] ) ) {
2986                 $cmd[] = $options['wrapper'];
2987         }
2988         $cmd[] = $script;
2989         // Escape each parameter for shell
2990         return implode( " ", array_map( 'wfEscapeShellArg', array_merge( $cmd, $parameters ) ) );
2991 }
2992
2993 /**
2994  * wfMerge attempts to merge differences between three texts.
2995  * Returns true for a clean merge and false for failure or a conflict.
2996  *
2997  * @param $old String
2998  * @param $mine String
2999  * @param $yours String
3000  * @param $result String
3001  * @return Bool
3002  */
3003 function wfMerge( $old, $mine, $yours, &$result ) {
3004         global $wgDiff3;
3005
3006         # This check may also protect against code injection in
3007         # case of broken installations.
3008         wfSuppressWarnings();
3009         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
3010         wfRestoreWarnings();
3011
3012         if( !$haveDiff3 ) {
3013                 wfDebug( "diff3 not found\n" );
3014                 return false;
3015         }
3016
3017         # Make temporary files
3018         $td = wfTempDir();
3019         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
3020         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
3021         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
3022
3023         fwrite( $oldtextFile, $old );
3024         fclose( $oldtextFile );
3025         fwrite( $mytextFile, $mine );
3026         fclose( $mytextFile );
3027         fwrite( $yourtextFile, $yours );
3028         fclose( $yourtextFile );
3029
3030         # Check for a conflict
3031         $cmd = $wgDiff3 . ' -a --overlap-only ' .
3032                 wfEscapeShellArg( $mytextName ) . ' ' .
3033                 wfEscapeShellArg( $oldtextName ) . ' ' .
3034                 wfEscapeShellArg( $yourtextName );
3035         $handle = popen( $cmd, 'r' );
3036
3037         if( fgets( $handle, 1024 ) ) {
3038                 $conflict = true;
3039         } else {
3040                 $conflict = false;
3041         }
3042         pclose( $handle );
3043
3044         # Merge differences
3045         $cmd = $wgDiff3 . ' -a -e --merge ' .
3046                 wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
3047         $handle = popen( $cmd, 'r' );
3048         $result = '';
3049         do {
3050                 $data = fread( $handle, 8192 );
3051                 if ( strlen( $data ) == 0 ) {
3052                         break;
3053                 }
3054                 $result .= $data;
3055         } while ( true );
3056         pclose( $handle );
3057         unlink( $mytextName );
3058         unlink( $oldtextName );
3059         unlink( $yourtextName );
3060
3061         if ( $result === '' && $old !== '' && !$conflict ) {
3062                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
3063                 $conflict = true;
3064         }
3065         return !$conflict;
3066 }
3067
3068 /**
3069  * Returns unified plain-text diff of two texts.
3070  * Useful for machine processing of diffs.
3071  *
3072  * @param $before String: the text before the changes.
3073  * @param $after String: the text after the changes.
3074  * @param $params String: command-line options for the diff command.
3075  * @return String: unified diff of $before and $after
3076  */
3077 function wfDiff( $before, $after, $params = '-u' ) {
3078         if ( $before == $after ) {
3079                 return '';
3080         }
3081
3082         global $wgDiff;
3083         wfSuppressWarnings();
3084         $haveDiff = $wgDiff && file_exists( $wgDiff );
3085         wfRestoreWarnings();
3086
3087         # This check may also protect against code injection in
3088         # case of broken installations.
3089         if( !$haveDiff ) {
3090                 wfDebug( "diff executable not found\n" );
3091                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
3092                 $format = new UnifiedDiffFormatter();
3093                 return $format->format( $diffs );
3094         }
3095
3096         # Make temporary files
3097         $td = wfTempDir();
3098         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
3099         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
3100
3101         fwrite( $oldtextFile, $before );
3102         fclose( $oldtextFile );
3103         fwrite( $newtextFile, $after );
3104         fclose( $newtextFile );
3105
3106         // Get the diff of the two files
3107         $cmd = "$wgDiff " . $params . ' ' . wfEscapeShellArg( $oldtextName, $newtextName );
3108
3109         $h = popen( $cmd, 'r' );
3110
3111         $diff = '';
3112
3113         do {
3114                 $data = fread( $h, 8192 );
3115                 if ( strlen( $data ) == 0 ) {
3116                         break;
3117                 }
3118                 $diff .= $data;
3119         } while ( true );
3120
3121         // Clean up
3122         pclose( $h );
3123         unlink( $oldtextName );
3124         unlink( $newtextName );
3125
3126         // Kill the --- and +++ lines. They're not useful.
3127         $diff_lines = explode( "\n", $diff );
3128         if ( strpos( $diff_lines[0], '---' ) === 0 ) {
3129                 unset( $diff_lines[0] );
3130         }
3131         if ( strpos( $diff_lines[1], '+++' ) === 0 ) {
3132                 unset( $diff_lines[1] );
3133         }
3134
3135         $diff = implode( "\n", $diff_lines );
3136
3137         return $diff;
3138 }
3139
3140 /**
3141  * This function works like "use VERSION" in Perl, the program will die with a
3142  * backtrace if the current version of PHP is less than the version provided
3143  *
3144  * This is useful for extensions which due to their nature are not kept in sync
3145  * with releases, and might depend on other versions of PHP than the main code
3146  *
3147  * Note: PHP might die due to parsing errors in some cases before it ever
3148  *       manages to call this function, such is life
3149  *
3150  * @see perldoc -f use
3151  *
3152  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
3153  *                 a float
3154  */
3155 function wfUsePHP( $req_ver ) {
3156         $php_ver = PHP_VERSION;
3157
3158         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
3159                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
3160         }
3161 }
3162
3163 /**
3164  * This function works like "use VERSION" in Perl except it checks the version
3165  * of MediaWiki, the program will die with a backtrace if the current version
3166  * of MediaWiki is less than the version provided.
3167  *
3168  * This is useful for extensions which due to their nature are not kept in sync
3169  * with releases
3170  *
3171  * @see perldoc -f use
3172  *
3173  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
3174  *                 a float
3175  */
3176 function wfUseMW( $req_ver ) {
3177         global $wgVersion;
3178
3179         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
3180                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
3181         }
3182 }
3183
3184 /**
3185  * Return the final portion of a pathname.
3186  * Reimplemented because PHP5's basename() is buggy with multibyte text.
3187  * http://bugs.php.net/bug.php?id=33898
3188  *
3189  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
3190  * We'll consider it so always, as we don't want \s in our Unix paths either.
3191  *
3192  * @param $path String
3193  * @param $suffix String: to remove if present
3194  * @return String
3195  */
3196 function wfBaseName( $path, $suffix = '' ) {
3197         $encSuffix = ( $suffix == '' )
3198                 ? ''
3199                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
3200         $matches = array();
3201         if( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
3202                 return $matches[1];
3203         } else {
3204                 return '';
3205         }
3206 }
3207
3208 /**
3209  * Generate a relative path name to the given file.
3210  * May explode on non-matching case-insensitive paths,
3211  * funky symlinks, etc.
3212  *
3213  * @param $path String: absolute destination path including target filename
3214  * @param $from String: Absolute source path, directory only
3215  * @return String
3216  */
3217 function wfRelativePath( $path, $from ) {
3218         // Normalize mixed input on Windows...
3219         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
3220         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
3221
3222         // Trim trailing slashes -- fix for drive root
3223         $path = rtrim( $path, DIRECTORY_SEPARATOR );
3224         $from = rtrim( $from, DIRECTORY_SEPARATOR );
3225
3226         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
3227         $against = explode( DIRECTORY_SEPARATOR, $from );
3228
3229         if( $pieces[0] !== $against[0] ) {
3230                 // Non-matching Windows drive letters?
3231                 // Return a full path.
3232                 return $path;
3233         }
3234
3235         // Trim off common prefix
3236         while( count( $pieces ) && count( $against )
3237                 && $pieces[0] == $against[0] ) {
3238                 array_shift( $pieces );
3239                 array_shift( $against );
3240         }
3241
3242         // relative dots to bump us to the parent
3243         while( count( $against ) ) {
3244                 array_unshift( $pieces, '..' );
3245                 array_shift( $against );
3246         }
3247
3248         array_push( $pieces, wfBaseName( $path ) );
3249
3250         return implode( DIRECTORY_SEPARATOR, $pieces );
3251 }
3252
3253 /**
3254  * Do any deferred updates and clear the list
3255  *
3256  * @deprecated since 1.19
3257  * @see DeferredUpdates::doUpdate()
3258  * @param $commit string
3259  */
3260 function wfDoUpdates( $commit = '' ) {
3261         wfDeprecated( __METHOD__, '1.19' );
3262         DeferredUpdates::doUpdates( $commit );
3263 }
3264
3265 /**
3266  * Convert an arbitrarily-long digit string from one numeric base
3267  * to another, optionally zero-padding to a minimum column width.
3268  *
3269  * Supports base 2 through 36; digit values 10-36 are represented
3270  * as lowercase letters a-z. Input is case-insensitive.
3271  *
3272  * @param $input String: of digits
3273  * @param $sourceBase Integer: 2-36
3274  * @param $destBase Integer: 2-36
3275  * @param $pad Integer: 1 or greater
3276  * @param $lowercase Boolean
3277  * @return String or false on invalid input
3278  */
3279 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1, $lowercase = true ) {
3280         $input = strval( $input );
3281         if( $sourceBase < 2 ||
3282                 $sourceBase > 36 ||
3283                 $destBase < 2 ||
3284                 $destBase > 36 ||
3285                 $pad < 1 ||
3286                 $sourceBase != intval( $sourceBase ) ||
3287                 $destBase != intval( $destBase ) ||
3288                 $pad != intval( $pad ) ||
3289                 !is_string( $input ) ||
3290                 $input == '' ) {
3291                 return false;
3292         }
3293         $digitChars = ( $lowercase ) ? '0123456789abcdefghijklmnopqrstuvwxyz' : '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
3294         $inDigits = array();
3295         $outChars = '';
3296
3297         // Decode and validate input string
3298         $input = strtolower( $input );
3299         for( $i = 0; $i < strlen( $input ); $i++ ) {
3300                 $n = strpos( $digitChars, $input[$i] );
3301                 if( $n === false || $n > $sourceBase ) {
3302                         return false;
3303                 }
3304                 $inDigits[] = $n;
3305         }
3306
3307         // Iterate over the input, modulo-ing out an output digit
3308         // at a time until input is gone.
3309         while( count( $inDigits ) ) {
3310                 $work = 0;
3311                 $workDigits = array();
3312
3313                 // Long division...
3314                 foreach( $inDigits as $digit ) {
3315                         $work *= $sourceBase;
3316                         $work += $digit;
3317
3318                         if( $work < $destBase ) {
3319                                 // Gonna need to pull another digit.
3320                                 if( count( $workDigits ) ) {
3321                                         // Avoid zero-padding; this lets us find
3322                                         // the end of the input very easily when
3323                                         // length drops to zero.
3324                                         $workDigits[] = 0;
3325                                 }
3326                         } else {
3327                                 // Finally! Actual division!
3328                                 $workDigits[] = intval( $work / $destBase );
3329
3330                                 // Isn't it annoying that most programming languages
3331                                 // don't have a single divide-and-remainder operator,
3332                                 // even though the CPU implements it that way?
3333                                 $work = $work % $destBase;
3334                         }
3335                 }
3336
3337                 // All that division leaves us with a remainder,
3338                 // which is conveniently our next output digit.
3339                 $outChars .= $digitChars[$work];
3340
3341                 // And we continue!
3342                 $inDigits = $workDigits;
3343         }
3344
3345         while( strlen( $outChars ) < $pad ) {
3346                 $outChars .= '0';
3347         }
3348
3349         return strrev( $outChars );
3350 }
3351
3352 /**
3353  * Create an object with a given name and an array of construct parameters
3354  *
3355  * @param $name String
3356  * @param $p Array: parameters
3357  * @return object
3358  * @deprecated since 1.18, warnings in 1.18, removal in 1.20
3359  */
3360 function wfCreateObject( $name, $p ) {
3361         wfDeprecated( __FUNCTION__, '1.18' );
3362         return MWFunction::newObj( $name, $p );
3363 }
3364
3365 /**
3366  * @return bool
3367  */
3368 function wfHttpOnlySafe() {
3369         global $wgHttpOnlyBlacklist;
3370
3371         if( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
3372                 foreach( $wgHttpOnlyBlacklist as $regex ) {
3373                         if( preg_match( $regex, $_SERVER['HTTP_USER_AGENT'] ) ) {
3374                                 return false;
3375                         }
3376                 }
3377         }
3378
3379         return true;
3380 }
3381
3382 /**
3383  * Override session_id before session startup if php's built-in
3384  * session generation code is not secure.
3385  */
3386 function wfFixSessionID() {
3387         // If the cookie or session id is already set we already have a session and should abort
3388         if ( isset( $_COOKIE[ session_name() ] ) || session_id() ) {
3389                 return;
3390         }
3391
3392         // PHP's built-in session entropy is enabled if:
3393         // - entropy_file is set or you're on Windows with php 5.3.3+
3394         // - AND entropy_length is > 0
3395         // We treat it as disabled if it doesn't have an entropy length of at least 32
3396         $entropyEnabled = (
3397                         ( wfIsWindows() && version_compare( PHP_VERSION, '5.3.3', '>=' ) )
3398                         || ini_get( 'session.entropy_file' )
3399                 )
3400                 && intval( ini_get( 'session.entropy_length' ) ) >= 32;
3401
3402         // If built-in entropy is not enabled or not sufficient override php's built in session id generation code
3403         if ( !$entropyEnabled ) {
3404                 wfDebug( __METHOD__ . ": PHP's built in entropy is disabled or not sufficient, overriding session id generation using our cryptrand source.\n" );
3405                 session_id( MWCryptRand::generateHex( 32 ) );
3406         }
3407 }
3408
3409 /**
3410  * Initialise php session
3411  *
3412  * @param $sessionId Bool
3413  */
3414 function wfSetupSession( $sessionId = false ) {
3415         global $wgSessionsInMemcached, $wgCookiePath, $wgCookieDomain,
3416                         $wgCookieSecure, $wgCookieHttpOnly, $wgSessionHandler;
3417         if( $wgSessionsInMemcached ) {
3418                 if ( !defined( 'MW_COMPILED' ) ) {
3419                         global $IP;
3420                         require_once( "$IP/includes/cache/MemcachedSessions.php" );
3421                 }
3422                 session_set_save_handler( 'memsess_open', 'memsess_close', 'memsess_read',
3423                         'memsess_write', 'memsess_destroy', 'memsess_gc' );
3424
3425                 // It's necessary to register a shutdown function to call session_write_close(),
3426                 // because by the time the request shutdown function for the session module is
3427                 // called, $wgMemc has already been destroyed. Shutdown functions registered
3428                 // this way are called before object destruction.
3429                 register_shutdown_function( 'memsess_write_close' );
3430         } elseif( $wgSessionHandler && $wgSessionHandler != ini_get( 'session.save_handler' ) ) {
3431                 # Only set this if $wgSessionHandler isn't null and session.save_handler
3432                 # hasn't already been set to the desired value (that causes errors)
3433                 ini_set( 'session.save_handler', $wgSessionHandler );
3434         }
3435         $httpOnlySafe = wfHttpOnlySafe() && $wgCookieHttpOnly;
3436         wfDebugLog( 'cookie',
3437                 'session_set_cookie_params: "' . implode( '", "',
3438                         array(
3439                                 0,
3440                                 $wgCookiePath,
3441                                 $wgCookieDomain,
3442                                 $wgCookieSecure,
3443                                 $httpOnlySafe ) ) . '"' );
3444         session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $httpOnlySafe );
3445         session_cache_limiter( 'private, must-revalidate' );
3446         if ( $sessionId ) {
3447                 session_id( $sessionId );
3448         } else {
3449                 wfFixSessionID();
3450         }
3451         wfSuppressWarnings();
3452         session_start();
3453         wfRestoreWarnings();
3454 }
3455
3456 /**
3457  * Get an object from the precompiled serialized directory
3458  *
3459  * @param $name String
3460  * @return Mixed: the variable on success, false on failure
3461  */
3462 function wfGetPrecompiledData( $name ) {
3463         global $IP;
3464
3465         $file = "$IP/serialized/$name";
3466         if ( file_exists( $file ) ) {
3467                 $blob = file_get_contents( $file );
3468                 if ( $blob ) {
3469                         return unserialize( $blob );
3470                 }
3471         }
3472         return false;
3473 }
3474
3475 /**
3476  * Get a cache key
3477  *
3478  * @param varargs
3479  * @return String
3480  */
3481 function wfMemcKey( /*... */ ) {
3482         global $wgCachePrefix;
3483         $prefix = $wgCachePrefix === false ? wfWikiID() : $wgCachePrefix;
3484         $args = func_get_args();
3485         $key = $prefix . ':' . implode( ':', $args );
3486         $key = str_replace( ' ', '_', $key );
3487         return $key;
3488 }
3489
3490 /**
3491  * Get a cache key for a foreign DB
3492  *
3493  * @param $db String
3494  * @param $prefix String
3495  * @param varargs String
3496  * @return String
3497  */
3498 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
3499         $args = array_slice( func_get_args(), 2 );
3500         if ( $prefix ) {
3501                 $key = "$db-$prefix:" . implode( ':', $args );
3502         } else {
3503                 $key = $db . ':' . implode( ':', $args );
3504         }
3505         return $key;
3506 }
3507
3508 /**
3509  * Get an ASCII string identifying this wiki
3510  * This is used as a prefix in memcached keys
3511  *
3512  * @return String
3513  */
3514 function wfWikiID() {
3515         global $wgDBprefix, $wgDBname;
3516         if ( $wgDBprefix ) {
3517                 return "$wgDBname-$wgDBprefix";
3518         } else {
3519                 return $wgDBname;
3520         }
3521 }
3522
3523 /**
3524  * Split a wiki ID into DB name and table prefix
3525  *
3526  * @param $wiki String
3527  *
3528  * @return array
3529  */
3530 function wfSplitWikiID( $wiki ) {
3531         $bits = explode( '-', $wiki, 2 );
3532         if ( count( $bits ) < 2 ) {
3533                 $bits[] = '';
3534         }
3535         return $bits;
3536 }
3537
3538 /**
3539  * Get a Database object.
3540  *
3541  * @param $db Integer: index of the connection to get. May be DB_MASTER for the
3542  *            master (for write queries), DB_SLAVE for potentially lagged read
3543  *            queries, or an integer >= 0 for a particular server.
3544  *
3545  * @param $groups Mixed: query groups. An array of group names that this query
3546  *                belongs to. May contain a single string if the query is only
3547  *                in one group.
3548  *
3549  * @param $wiki String: the wiki ID, or false for the current wiki
3550  *
3551  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
3552  * will always return the same object, unless the underlying connection or load
3553  * balancer is manually destroyed.
3554  *
3555  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
3556  * updater to ensure that a proper database is being updated.
3557  *
3558  * @return DatabaseBase
3559  */
3560 function &wfGetDB( $db, $groups = array(), $wiki = false ) {
3561         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
3562 }
3563
3564 /**
3565  * Get a load balancer object.
3566  *
3567  * @param $wiki String: wiki ID, or false for the current wiki
3568  * @return LoadBalancer
3569  */
3570 function wfGetLB( $wiki = false ) {
3571         return wfGetLBFactory()->getMainLB( $wiki );
3572 }
3573
3574 /**
3575  * Get the load balancer factory object
3576  *
3577  * @return LBFactory
3578  */
3579 function &wfGetLBFactory() {
3580         return LBFactory::singleton();
3581 }
3582
3583 /**
3584  * Find a file.
3585  * Shortcut for RepoGroup::singleton()->findFile()
3586  *
3587  * @param $title String or Title object
3588  * @param $options array Associative array of options:
3589  *     time:           requested time for an archived image, or false for the
3590  *                     current version. An image object will be returned which was
3591  *                     created at the specified time.
3592  *
3593  *     ignoreRedirect: If true, do not follow file redirects
3594  *
3595  *     private:        If true, return restricted (deleted) files if the current
3596  *                     user is allowed to view them. Otherwise, such files will not
3597  *                     be found.
3598  *
3599  *     bypassCache:    If true, do not use the process-local cache of File objects
3600  *
3601  * @return File, or false if the file does not exist
3602  */
3603 function wfFindFile( $title, $options = array() ) {
3604         return RepoGroup::singleton()->findFile( $title, $options );
3605 }
3606
3607 /**
3608  * Get an object referring to a locally registered file.
3609  * Returns a valid placeholder object if the file does not exist.
3610  *
3611  * @param $title Title|String
3612  * @return LocalFile|null A File, or null if passed an invalid Title
3613  */
3614 function wfLocalFile( $title ) {
3615         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
3616 }
3617
3618 /**
3619  * Stream a file to the browser. Back-compat alias for StreamFile::stream()
3620  * @deprecated since 1.19
3621  */
3622 function wfStreamFile( $fname, $headers = array() ) {
3623         wfDeprecated( __FUNCTION__, '1.19' );
3624         StreamFile::stream( $fname, $headers );
3625 }
3626
3627 /**
3628  * Should low-performance queries be disabled?
3629  *
3630  * @return Boolean
3631  * @codeCoverageIgnore
3632  */
3633 function wfQueriesMustScale() {
3634         global $wgMiserMode;
3635         return $wgMiserMode
3636                 || ( SiteStats::pages() > 100000
3637                 && SiteStats::edits() > 1000000
3638                 && SiteStats::users() > 10000 );
3639 }
3640
3641 /**
3642  * Get the path to a specified script file, respecting file
3643  * extensions; this is a wrapper around $wgScriptExtension etc.
3644  *
3645  * @param $script String: script filename, sans extension
3646  * @return String
3647  */
3648 function wfScript( $script = 'index' ) {
3649         global $wgScriptPath, $wgScriptExtension;
3650         return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
3651 }
3652
3653 /**
3654  * Get the script URL.
3655  *
3656  * @return string script URL
3657  */
3658 function wfGetScriptUrl() {
3659         if( isset( $_SERVER['SCRIPT_NAME'] ) ) {
3660                 #
3661                 # as it was called, minus the query string.
3662                 #
3663                 # Some sites use Apache rewrite rules to handle subdomains,
3664                 # and have PHP set up in a weird way that causes PHP_SELF
3665                 # to contain the rewritten URL instead of the one that the
3666                 # outside world sees.
3667                 #
3668                 # If in this mode, use SCRIPT_URL instead, which mod_rewrite
3669                 # provides containing the "before" URL.
3670                 return $_SERVER['SCRIPT_NAME'];
3671         } else {
3672                 return $_SERVER['URL'];
3673         }
3674 }
3675
3676 /**
3677  * Convenience function converts boolean values into "true"
3678  * or "false" (string) values
3679  *
3680  * @param $value Boolean
3681  * @return String
3682  */
3683 function wfBoolToStr( $value ) {
3684         return $value ? 'true' : 'false';
3685 }
3686
3687 /**
3688  * Load an extension messages file
3689  *
3690  * @deprecated since 1.16, warnings in 1.18, remove in 1.20
3691  * @codeCoverageIgnore
3692  */
3693 function wfLoadExtensionMessages() {
3694         wfDeprecated( __FUNCTION__, '1.16' );
3695 }
3696
3697 /**
3698  * Get a platform-independent path to the null file, e.g. /dev/null
3699  *
3700  * @return string
3701  */
3702 function wfGetNull() {
3703         return wfIsWindows()
3704                 ? 'NUL'
3705                 : '/dev/null';
3706 }
3707
3708 /**
3709  * Modern version of wfWaitForSlaves(). Instead of looking at replication lag
3710  * and waiting for it to go down, this waits for the slaves to catch up to the
3711  * master position. Use this when updating very large numbers of rows, as
3712  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
3713  * a no-op if there are no slaves.
3714  *
3715  * @param $maxLag Integer (deprecated)
3716  * @param $wiki mixed Wiki identifier accepted by wfGetLB
3717  */
3718 function wfWaitForSlaves( $maxLag = false, $wiki = false ) {
3719         $lb = wfGetLB( $wiki );
3720         // bug 27975 - Don't try to wait for slaves if there are none
3721         // Prevents permission error when getting master position
3722         if ( $lb->getServerCount() > 1 ) {
3723                 $dbw = $lb->getConnection( DB_MASTER );
3724                 $pos = $dbw->getMasterPos();
3725                 $lb->waitForAll( $pos );
3726         }
3727 }
3728
3729 /**
3730  * Used to be used for outputting text in the installer/updater
3731  * @deprecated since 1.18, warnings in 1.18, remove in 1.20
3732  */
3733 function wfOut( $s ) {
3734         wfDeprecated( __FUNCTION__, '1.18' );
3735         global $wgCommandLineMode;
3736         if ( $wgCommandLineMode ) {
3737                 echo $s;
3738         } else {
3739                 echo htmlspecialchars( $s );
3740         }
3741         flush();
3742 }
3743
3744 /**
3745  * Count down from $n to zero on the terminal, with a one-second pause
3746  * between showing each number. For use in command-line scripts.
3747  * @codeCoverageIgnore
3748  * @param $n int
3749  */
3750 function wfCountDown( $n ) {
3751         for ( $i = $n; $i >= 0; $i-- ) {
3752                 if ( $i != $n ) {
3753                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3754                 }
3755                 echo $i;
3756                 flush();
3757                 if ( $i ) {
3758                         sleep( 1 );
3759                 }
3760         }
3761         echo "\n";
3762 }
3763
3764 /**
3765  * Generate a random 32-character hexadecimal token.
3766  * @param $salt Mixed: some sort of salt, if necessary, to add to random
3767  *              characters before hashing.
3768  * @return string
3769  * @codeCoverageIgnore
3770  * @deprecated since 1.20; Please use MWCryptRand for security purposes and wfRandomString for pesudo-random strings
3771  * @warning This method is NOT secure. Additionally it has many callers that use it for pesudo-random purposes.
3772  */
3773 function wfGenerateToken( $salt = '' ) {
3774         wfDeprecated( __METHOD__, '1.20' );
3775         $salt = serialize( $salt );
3776         return md5( mt_rand( 0, 0x7fffffff ) . $salt );
3777 }
3778
3779 /**
3780  * Replace all invalid characters with -
3781  *
3782  * @param $name Mixed: filename to process
3783  * @return String
3784  */
3785 function wfStripIllegalFilenameChars( $name ) {
3786         global $wgIllegalFileChars;
3787         $name = wfBaseName( $name );
3788         $name = preg_replace(
3789                 "/[^" . Title::legalChars() . "]" .
3790                         ( $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '' ) .
3791                         "/",
3792                 '-',
3793                 $name
3794         );
3795         return $name;
3796 }
3797
3798 /**
3799  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit;
3800  *
3801  * @return Integer value memory was set to.
3802  */
3803 function wfMemoryLimit() {
3804         global $wgMemoryLimit;
3805         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3806         if( $memlimit != -1 ) {
3807                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3808                 if( $conflimit == -1 ) {
3809                         wfDebug( "Removing PHP's memory limit\n" );
3810                         wfSuppressWarnings();
3811                         ini_set( 'memory_limit', $conflimit );
3812                         wfRestoreWarnings();
3813                         return $conflimit;
3814                 } elseif ( $conflimit > $memlimit ) {
3815                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3816                         wfSuppressWarnings();
3817                         ini_set( 'memory_limit', $conflimit );
3818                         wfRestoreWarnings();
3819                         return $conflimit;
3820                 }
3821         }
3822         return $memlimit;
3823 }
3824
3825 /**
3826  * Converts shorthand byte notation to integer form
3827  *
3828  * @param $string String
3829  * @return Integer
3830  */
3831 function wfShorthandToInteger( $string = '' ) {
3832         $string = trim( $string );
3833         if( $string === '' ) {
3834                 return -1;
3835         }
3836         $last = $string[strlen( $string ) - 1];
3837         $val = intval( $string );
3838         switch( $last ) {
3839                 case 'g':
3840                 case 'G':
3841                         $val *= 1024;
3842                         // break intentionally missing
3843                 case 'm':
3844                 case 'M':
3845                         $val *= 1024;
3846                         // break intentionally missing
3847                 case 'k':
3848                 case 'K':
3849                         $val *= 1024;
3850         }
3851
3852         return $val;
3853 }
3854
3855 /**
3856  * Get the normalised IETF language tag
3857  * See unit test for examples.
3858  *
3859  * @param $code String: The language code.
3860  * @return String: The language code which complying with BCP 47 standards.
3861  */
3862 function wfBCP47( $code ) {
3863         $codeSegment = explode( '-', $code );
3864         $codeBCP = array();
3865         foreach ( $codeSegment as $segNo => $seg ) {
3866                 if ( count( $codeSegment ) > 0 ) {
3867                         // when previous segment is x, it is a private segment and should be lc
3868                         if( $segNo > 0 && strtolower( $codeSegment[( $segNo - 1 )] ) == 'x' ) {
3869                                 $codeBCP[$segNo] = strtolower( $seg );
3870                         // ISO 3166 country code
3871                         } elseif ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3872                                 $codeBCP[$segNo] = strtoupper( $seg );
3873                         // ISO 15924 script code
3874                         } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3875                                 $codeBCP[$segNo] = ucfirst( strtolower( $seg ) );
3876                         // Use lowercase for other cases
3877                         } else {
3878                                 $codeBCP[$segNo] = strtolower( $seg );
3879                         }
3880                 } else {
3881                 // Use lowercase for single segment
3882                         $codeBCP[$segNo] = strtolower( $seg );
3883                 }
3884         }
3885         $langCode = implode( '-', $codeBCP );
3886         return $langCode;
3887 }
3888
3889 /**
3890  * Get a cache object.
3891  *
3892  * @param $inputType integer Cache type, one the the CACHE_* constants.
3893  * @return BagOStuff
3894  */
3895 function wfGetCache( $inputType ) {
3896         return ObjectCache::getInstance( $inputType );
3897 }
3898
3899 /**
3900  * Get the main cache object
3901  *
3902  * @return BagOStuff
3903  */
3904 function wfGetMainCache() {
3905         global $wgMainCacheType;
3906         return ObjectCache::getInstance( $wgMainCacheType );
3907 }
3908
3909 /**
3910  * Get the cache object used by the message cache
3911  *
3912  * @return BagOStuff
3913  */
3914 function wfGetMessageCacheStorage() {
3915         global $wgMessageCacheType;
3916         return ObjectCache::getInstance( $wgMessageCacheType );
3917 }
3918
3919 /**
3920  * Get the cache object used by the parser cache
3921  *
3922  * @return BagOStuff
3923  */
3924 function wfGetParserCacheStorage() {
3925         global $wgParserCacheType;
3926         return ObjectCache::getInstance( $wgParserCacheType );
3927 }
3928
3929 /**
3930  * Get the cache object used by the language converter
3931  *
3932  * @return BagOStuff
3933  */
3934 function wfGetLangConverterCacheStorage() {
3935         global $wgLanguageConverterCacheType;
3936         return ObjectCache::getInstance( $wgLanguageConverterCacheType );
3937 }
3938
3939 /**
3940  * Call hook functions defined in $wgHooks
3941  *
3942  * @param $event String: event name
3943  * @param $args Array: parameters passed to hook functions
3944  * @return Boolean True if no handler aborted the hook
3945  */
3946 function wfRunHooks( $event, $args = array() ) {
3947         return Hooks::run( $event, $args );
3948 }
3949
3950 /**
3951  * Wrapper around php's unpack.
3952  *
3953  * @param $format String: The format string (See php's docs)
3954  * @param $data: A binary string of binary data
3955  * @param $length integer or false: The minimun length of $data. This is to
3956  *      prevent reading beyond the end of $data. false to disable the check.
3957  *
3958  * Also be careful when using this function to read unsigned 32 bit integer
3959  * because php might make it negative.
3960  *
3961  * @throws MWException if $data not long enough, or if unpack fails
3962  * @return array Associative array of the extracted data
3963  */
3964 function wfUnpack( $format, $data, $length=false ) {
3965         if ( $length !== false ) {
3966                 $realLen = strlen( $data );
3967                 if ( $realLen < $length ) {
3968                         throw new MWException( "Tried to use wfUnpack on a "
3969                                 . "string of length $realLen, but needed one "
3970                                 . "of at least length $length."
3971                         );
3972                 }
3973         }
3974
3975         wfSuppressWarnings();
3976         $result = unpack( $format, $data );
3977         wfRestoreWarnings();
3978
3979         if ( $result === false ) {
3980                 // If it cannot extract the packed data.
3981                 throw new MWException( "unpack could not unpack binary data" );
3982         }
3983         return $result;
3984 }
3985
3986 /**
3987  * Determine if an image exists on the 'bad image list'.
3988  *
3989  * The format of MediaWiki:Bad_image_list is as follows:
3990  *    * Only list items (lines starting with "*") are considered
3991  *    * The first link on a line must be a link to a bad image
3992  *    * Any subsequent links on the same line are considered to be exceptions,
3993  *      i.e. articles where the image may occur inline.
3994  *
3995  * @param $name string the image name to check
3996  * @param $contextTitle Title|bool the page on which the image occurs, if known
3997  * @param $blacklist string wikitext of a file blacklist
3998  * @return bool
3999  */
4000 function wfIsBadImage( $name, $contextTitle = false, $blacklist = null ) {
4001         static $badImageCache = null; // based on bad_image_list msg
4002         wfProfileIn( __METHOD__ );
4003
4004         # Handle redirects
4005         $redirectTitle = RepoGroup::singleton()->checkRedirect( Title::makeTitle( NS_FILE, $name ) );
4006         if( $redirectTitle ) {
4007                 $name = $redirectTitle->getDbKey();
4008         }
4009
4010         # Run the extension hook
4011         $bad = false;
4012         if( !wfRunHooks( 'BadImage', array( $name, &$bad ) ) ) {
4013                 wfProfileOut( __METHOD__ );
4014                 return $bad;
4015         }
4016
4017         $cacheable = ( $blacklist === null );
4018         if( $cacheable && $badImageCache !== null ) {
4019                 $badImages = $badImageCache;
4020         } else { // cache miss
4021                 if ( $blacklist === null ) {
4022                         $blacklist = wfMsgForContentNoTrans( 'bad_image_list' ); // site list
4023                 }
4024                 # Build the list now
4025                 $badImages = array();
4026                 $lines = explode( "\n", $blacklist );
4027                 foreach( $lines as $line ) {
4028                         # List items only
4029                         if ( substr( $line, 0, 1 ) !== '*' ) {
4030                                 continue;
4031                         }
4032
4033                         # Find all links
4034                         $m = array();
4035                         if ( !preg_match_all( '/\[\[:?(.*?)\]\]/', $line, $m ) ) {
4036                                 continue;
4037                         }
4038
4039                         $exceptions = array();
4040                         $imageDBkey = false;
4041                         foreach ( $m[1] as $i => $titleText ) {
4042                                 $title = Title::newFromText( $titleText );
4043                                 if ( !is_null( $title ) ) {
4044                                         if ( $i == 0 ) {
4045                                                 $imageDBkey = $title->getDBkey();
4046                                         } else {
4047                                                 $exceptions[$title->getPrefixedDBkey()] = true;
4048                                         }
4049                                 }
4050                         }
4051
4052                         if ( $imageDBkey !== false ) {
4053                                 $badImages[$imageDBkey] = $exceptions;
4054                         }
4055                 }
4056                 if ( $cacheable ) {
4057                         $badImageCache = $badImages;
4058                 }
4059         }
4060
4061         $contextKey = $contextTitle ? $contextTitle->getPrefixedDBkey() : false;
4062         $bad = isset( $badImages[$name] ) && !isset( $badImages[$name][$contextKey] );
4063         wfProfileOut( __METHOD__ );
4064         return $bad;
4065 }