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, $wgDBerrorLogInUTC;
1057         if ( $wgDBerrorLog ) {
1058                 $host = wfHostname();
1059                 $wiki = wfWikiID();
1060
1061                 if( $wgDBerrorLogInUTC ) {
1062                         $wikiTimezone = date_default_timezone_get();
1063                         date_default_timezone_set( 'UTC' );
1064                 }
1065                 $date = date( 'D M j G:i:s T Y' );
1066                 if( $wgDBerrorLogInUTC ) {
1067                         // Restore timezone
1068                         date_default_timezone_set( $wikiTimezone );
1069                 }
1070
1071                 $text = "$date\t$host\t$wiki\t$text";
1072                 wfErrorLog( $text, $wgDBerrorLog );
1073         }
1074 }
1075
1076 /**
1077  * Throws a warning that $function is deprecated
1078  *
1079  * @param $function String
1080  * @param $version String|bool: Version of MediaWiki that the function was deprecated in (Added in 1.19).
1081  * @param $component String|bool: Added in 1.19.
1082  * @param $callerOffset integer: How far up the callstack is the original
1083  *    caller. 2 = function that called the function that called
1084  *    wfDeprecated (Added in 1.20)
1085  *
1086  * @return null
1087  */
1088 function wfDeprecated( $function, $version = false, $component = false, $callerOffset = 2 ) {
1089         static $functionsWarned = array();
1090
1091         MWDebug::deprecated( $function, $version, $component );
1092
1093         if ( !isset( $functionsWarned[$function] ) ) {
1094                 $functionsWarned[$function] = true;
1095
1096                 if ( $version ) {
1097                         global $wgDeprecationReleaseLimit;
1098
1099                         if ( $wgDeprecationReleaseLimit && $component === false ) {
1100                                 # Strip -* off the end of $version so that branches can use the
1101                                 # format #.##-branchname to avoid issues if the branch is merged into
1102                                 # a version of MediaWiki later than what it was branched from
1103                                 $comparableVersion = preg_replace( '/-.*$/', '', $version );
1104
1105                                 # If the comparableVersion is larger than our release limit then
1106                                 # skip the warning message for the deprecation
1107                                 if ( version_compare( $wgDeprecationReleaseLimit, $comparableVersion, '<' ) ) {
1108                                         return;
1109                                 }
1110                         }
1111
1112                         $component = $component === false ? 'MediaWiki' : $component;
1113                         wfWarn( "Use of $function was deprecated in $component $version.", $callerOffset );
1114                 } else {
1115                         wfWarn( "Use of $function is deprecated.", $callerOffset );
1116                 }
1117         }
1118 }
1119
1120 /**
1121  * Send a warning either to the debug log or in a PHP error depending on
1122  * $wgDevelopmentWarnings
1123  *
1124  * @param $msg String: message to send
1125  * @param $callerOffset Integer: number of items to go back in the backtrace to
1126  *        find the correct caller (1 = function calling wfWarn, ...)
1127  * @param $level Integer: PHP error level; only used when $wgDevelopmentWarnings
1128  *        is true
1129  */
1130 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
1131         global $wgDevelopmentWarnings;
1132
1133         MWDebug::warning( $msg, $callerOffset + 2 );
1134
1135         $callers = wfDebugBacktrace();
1136         if ( isset( $callers[$callerOffset + 1] ) ) {
1137                 $callerfunc = $callers[$callerOffset + 1];
1138                 $callerfile = $callers[$callerOffset];
1139                 if ( isset( $callerfile['file'] ) && isset( $callerfile['line'] ) ) {
1140                         $file = $callerfile['file'] . ' at line ' . $callerfile['line'];
1141                 } else {
1142                         $file = '(internal function)';
1143                 }
1144                 $func = '';
1145                 if ( isset( $callerfunc['class'] ) ) {
1146                         $func .= $callerfunc['class'] . '::';
1147                 }
1148                 if ( isset( $callerfunc['function'] ) ) {
1149                         $func .= $callerfunc['function'];
1150                 }
1151                 $msg .= " [Called from $func in $file]";
1152         }
1153
1154         if ( $wgDevelopmentWarnings ) {
1155                 trigger_error( $msg, $level );
1156         } else {
1157                 wfDebug( "$msg\n" );
1158         }
1159 }
1160
1161 /**
1162  * Log to a file without getting "file size exceeded" signals.
1163  *
1164  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
1165  * send lines to the specified port, prefixed by the specified prefix and a space.
1166  *
1167  * @param $text String
1168  * @param $file String filename
1169  */
1170 function wfErrorLog( $text, $file ) {
1171         if ( substr( $file, 0, 4 ) == 'udp:' ) {
1172                 # Needs the sockets extension
1173                 if ( preg_match( '!^(tcp|udp):(?://)?\[([0-9a-fA-F:]+)\]:(\d+)(?:/(.*))?$!', $file, $m ) ) {
1174                         // IPv6 bracketed host
1175                         $host = $m[2];
1176                         $port = intval( $m[3] );
1177                         $prefix = isset( $m[4] ) ? $m[4] : false;
1178                         $domain = AF_INET6;
1179                 } elseif ( preg_match( '!^(tcp|udp):(?://)?([a-zA-Z0-9.-]+):(\d+)(?:/(.*))?$!', $file, $m ) ) {
1180                         $host = $m[2];
1181                         if ( !IP::isIPv4( $host ) ) {
1182                                 $host = gethostbyname( $host );
1183                         }
1184                         $port = intval( $m[3] );
1185                         $prefix = isset( $m[4] ) ? $m[4] : false;
1186                         $domain = AF_INET;
1187                 } else {
1188                         throw new MWException( __METHOD__ . ': Invalid UDP specification' );
1189                 }
1190
1191                 // Clean it up for the multiplexer
1192                 if ( strval( $prefix ) !== '' ) {
1193                         $text = preg_replace( '/^/m', $prefix . ' ', $text );
1194
1195                         // Limit to 64KB
1196                         if ( strlen( $text ) > 65506 ) {
1197                                 $text = substr( $text, 0, 65506 );
1198                         }
1199
1200                         if ( substr( $text, -1 ) != "\n" ) {
1201                                 $text .= "\n";
1202                         }
1203                 } elseif ( strlen( $text ) > 65507 ) {
1204                         $text = substr( $text, 0, 65507 );
1205                 }
1206
1207                 $sock = socket_create( $domain, SOCK_DGRAM, SOL_UDP );
1208                 if ( !$sock ) {
1209                         return;
1210                 }
1211
1212                 socket_sendto( $sock, $text, strlen( $text ), 0, $host, $port );
1213                 socket_close( $sock );
1214         } else {
1215                 wfSuppressWarnings();
1216                 $exists = file_exists( $file );
1217                 $size = $exists ? filesize( $file ) : false;
1218                 if ( !$exists || ( $size !== false && $size + strlen( $text ) < 0x7fffffff ) ) {
1219                         file_put_contents( $file, $text, FILE_APPEND );
1220                 }
1221                 wfRestoreWarnings();
1222         }
1223 }
1224
1225 /**
1226  * @todo document
1227  */
1228 function wfLogProfilingData() {
1229         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
1230         global $wgProfileLimit, $wgUser;
1231
1232         $profiler = Profiler::instance();
1233
1234         # Profiling must actually be enabled...
1235         if ( $profiler->isStub() ) {
1236                 return;
1237         }
1238
1239         // Get total page request time and only show pages that longer than
1240         // $wgProfileLimit time (default is 0)
1241         $elapsed = microtime( true ) - $wgRequestTime;
1242         if ( $elapsed <= $wgProfileLimit ) {
1243                 return;
1244         }
1245
1246         $profiler->logData();
1247
1248         // Check whether this should be logged in the debug file.
1249         if ( $wgDebugLogFile == '' || ( !$wgDebugRawPage && wfIsDebugRawPage() ) ) {
1250                 return;
1251         }
1252
1253         $forward = '';
1254         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
1255                 $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
1256         }
1257         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
1258                 $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
1259         }
1260         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
1261                 $forward .= ' from ' . $_SERVER['HTTP_FROM'];
1262         }
1263         if ( $forward ) {
1264                 $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
1265         }
1266         // Don't load $wgUser at this late stage just for statistics purposes
1267         // @todo FIXME: We can detect some anons even if it is not loaded. See User::getId()
1268         if ( $wgUser->isItemLoaded( 'id' ) && $wgUser->isAnon() ) {
1269                 $forward .= ' anon';
1270         }
1271         $log = sprintf( "%s\t%04.3f\t%s\n",
1272                 gmdate( 'YmdHis' ), $elapsed,
1273                 urldecode( $wgRequest->getRequestURL() . $forward ) );
1274
1275         wfErrorLog( $log . $profiler->getOutput(), $wgDebugLogFile );
1276 }
1277
1278 /**
1279  * Increment a statistics counter
1280  *
1281  * @param $key String
1282  * @param $count Int
1283  */
1284 function wfIncrStats( $key, $count = 1 ) {
1285         global $wgStatsMethod;
1286
1287         $count = intval( $count );
1288
1289         if( $wgStatsMethod == 'udp' ) {
1290                 global $wgUDPProfilerHost, $wgUDPProfilerPort, $wgDBname, $wgAggregateStatsID;
1291                 static $socket;
1292
1293                 $id = $wgAggregateStatsID !== false ? $wgAggregateStatsID : $wgDBname;
1294
1295                 if ( !$socket ) {
1296                         $socket = socket_create( AF_INET, SOCK_DGRAM, SOL_UDP );
1297                         $statline = "stats/{$id} - 1 1 1 1 1 -total\n";
1298                         socket_sendto(
1299                                 $socket,
1300                                 $statline,
1301                                 strlen( $statline ),
1302                                 0,
1303                                 $wgUDPProfilerHost,
1304                                 $wgUDPProfilerPort
1305                         );
1306                 }
1307                 $statline = "stats/{$id} - {$count} 1 1 1 1 {$key}\n";
1308                 wfSuppressWarnings();
1309                 socket_sendto(
1310                         $socket,
1311                         $statline,
1312                         strlen( $statline ),
1313                         0,
1314                         $wgUDPProfilerHost,
1315                         $wgUDPProfilerPort
1316                 );
1317                 wfRestoreWarnings();
1318         } elseif( $wgStatsMethod == 'cache' ) {
1319                 global $wgMemc;
1320                 $key = wfMemcKey( 'stats', $key );
1321                 if ( is_null( $wgMemc->incr( $key, $count ) ) ) {
1322                         $wgMemc->add( $key, $count );
1323                 }
1324         } else {
1325                 // Disabled
1326         }
1327 }
1328
1329 /**
1330  * Check if the wiki read-only lock file is present. This can be used to lock
1331  * off editing functions, but doesn't guarantee that the database will not be
1332  * modified.
1333  *
1334  * @return bool
1335  */
1336 function wfReadOnly() {
1337         global $wgReadOnlyFile, $wgReadOnly;
1338
1339         if ( !is_null( $wgReadOnly ) ) {
1340                 return (bool)$wgReadOnly;
1341         }
1342         if ( $wgReadOnlyFile == '' ) {
1343                 return false;
1344         }
1345         // Set $wgReadOnly for faster access next time
1346         if ( is_file( $wgReadOnlyFile ) ) {
1347                 $wgReadOnly = file_get_contents( $wgReadOnlyFile );
1348         } else {
1349                 $wgReadOnly = false;
1350         }
1351         return (bool)$wgReadOnly;
1352 }
1353
1354 /**
1355  * @return bool
1356  */
1357 function wfReadOnlyReason() {
1358         global $wgReadOnly;
1359         wfReadOnly();
1360         return $wgReadOnly;
1361 }
1362
1363 /**
1364  * Return a Language object from $langcode
1365  *
1366  * @param $langcode Mixed: either:
1367  *                  - a Language object
1368  *                  - code of the language to get the message for, if it is
1369  *                    a valid code create a language for that language, if
1370  *                    it is a string but not a valid code then make a basic
1371  *                    language object
1372  *                  - a boolean: if it's false then use the global object for
1373  *                    the current user's language (as a fallback for the old parameter
1374  *                    functionality), or if it is true then use global object
1375  *                    for the wiki's content language.
1376  * @return Language object
1377  */
1378 function wfGetLangObj( $langcode = false ) {
1379         # Identify which language to get or create a language object for.
1380         # Using is_object here due to Stub objects.
1381         if( is_object( $langcode ) ) {
1382                 # Great, we already have the object (hopefully)!
1383                 return $langcode;
1384         }
1385
1386         global $wgContLang, $wgLanguageCode;
1387         if( $langcode === true || $langcode === $wgLanguageCode ) {
1388                 # $langcode is the language code of the wikis content language object.
1389                 # or it is a boolean and value is true
1390                 return $wgContLang;
1391         }
1392
1393         global $wgLang;
1394         if( $langcode === false || $langcode === $wgLang->getCode() ) {
1395                 # $langcode is the language code of user language object.
1396                 # or it was a boolean and value is false
1397                 return $wgLang;
1398         }
1399
1400         $validCodes = array_keys( Language::fetchLanguageNames() );
1401         if( in_array( $langcode, $validCodes ) ) {
1402                 # $langcode corresponds to a valid language.
1403                 return Language::factory( $langcode );
1404         }
1405
1406         # $langcode is a string, but not a valid language code; use content language.
1407         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
1408         return $wgContLang;
1409 }
1410
1411 /**
1412  * Old function when $wgBetterDirectionality existed
1413  * All usage removed, wfUILang can be removed in near future
1414  *
1415  * @deprecated since 1.18
1416  * @return Language
1417  */
1418 function wfUILang() {
1419         wfDeprecated( __METHOD__, '1.18' );
1420         global $wgLang;
1421         return $wgLang;
1422 }
1423
1424 /**
1425  * This is the new function for getting translated interface messages.
1426  * See the Message class for documentation how to use them.
1427  * The intention is that this function replaces all old wfMsg* functions.
1428  * @param $key \string Message key.
1429  * Varargs: normal message parameters.
1430  * @return Message
1431  * @since 1.17
1432  */
1433 function wfMessage( $key /*...*/) {
1434         $params = func_get_args();
1435         array_shift( $params );
1436         if ( isset( $params[0] ) && is_array( $params[0] ) ) {
1437                 $params = $params[0];
1438         }
1439         return new Message( $key, $params );
1440 }
1441
1442 /**
1443  * This function accepts multiple message keys and returns a message instance
1444  * for the first message which is non-empty. If all messages are empty then an
1445  * instance of the first message key is returned.
1446  * @param varargs: message keys
1447  * @return Message
1448  * @since 1.18
1449  */
1450 function wfMessageFallback( /*...*/ ) {
1451         $args = func_get_args();
1452         return MWFunction::callArray( 'Message::newFallbackSequence', $args );
1453 }
1454
1455 /**
1456  * Get a message from anywhere, for the current user language.
1457  *
1458  * Use wfMsgForContent() instead if the message should NOT
1459  * change depending on the user preferences.
1460  *
1461  * @deprecated since 1.18
1462  *
1463  * @param $key String: lookup key for the message, usually
1464  *    defined in languages/Language.php
1465  *
1466  * Parameters to the message, which can be used to insert variable text into
1467  * it, can be passed to this function in the following formats:
1468  * - One per argument, starting at the second parameter
1469  * - As an array in the second parameter
1470  * These are not shown in the function definition.
1471  *
1472  * @return String
1473  */
1474 function wfMsg( $key ) {
1475         $args = func_get_args();
1476         array_shift( $args );
1477         return wfMsgReal( $key, $args );
1478 }
1479
1480 /**
1481  * Same as above except doesn't transform the message
1482  *
1483  * @deprecated since 1.18
1484  *
1485  * @param $key String
1486  * @return String
1487  */
1488 function wfMsgNoTrans( $key ) {
1489         $args = func_get_args();
1490         array_shift( $args );
1491         return wfMsgReal( $key, $args, true, false, false );
1492 }
1493
1494 /**
1495  * Get a message from anywhere, for the current global language
1496  * set with $wgLanguageCode.
1497  *
1498  * Use this if the message should NOT change dependent on the
1499  * language set in the user's preferences. This is the case for
1500  * most text written into logs, as well as link targets (such as
1501  * the name of the copyright policy page). Link titles, on the
1502  * other hand, should be shown in the UI language.
1503  *
1504  * Note that MediaWiki allows users to change the user interface
1505  * language in their preferences, but a single installation
1506  * typically only contains content in one language.
1507  *
1508  * Be wary of this distinction: If you use wfMsg() where you should
1509  * use wfMsgForContent(), a user of the software may have to
1510  * customize potentially hundreds of messages in
1511  * order to, e.g., fix a link in every possible language.
1512  *
1513  * @deprecated since 1.18
1514  *
1515  * @param $key String: lookup key for the message, usually
1516  *     defined in languages/Language.php
1517  * @return String
1518  */
1519 function wfMsgForContent( $key ) {
1520         global $wgForceUIMsgAsContentMsg;
1521         $args = func_get_args();
1522         array_shift( $args );
1523         $forcontent = true;
1524         if( is_array( $wgForceUIMsgAsContentMsg ) &&
1525                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
1526         {
1527                 $forcontent = false;
1528         }
1529         return wfMsgReal( $key, $args, true, $forcontent );
1530 }
1531
1532 /**
1533  * Same as above except doesn't transform the message
1534  *
1535  * @deprecated since 1.18
1536  *
1537  * @param $key String
1538  * @return String
1539  */
1540 function wfMsgForContentNoTrans( $key ) {
1541         global $wgForceUIMsgAsContentMsg;
1542         $args = func_get_args();
1543         array_shift( $args );
1544         $forcontent = true;
1545         if( is_array( $wgForceUIMsgAsContentMsg ) &&
1546                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
1547         {
1548                 $forcontent = false;
1549         }
1550         return wfMsgReal( $key, $args, true, $forcontent, false );
1551 }
1552
1553 /**
1554  * Really get a message
1555  *
1556  * @deprecated since 1.18
1557  *
1558  * @param $key String: key to get.
1559  * @param $args
1560  * @param $useDB Boolean
1561  * @param $forContent Mixed: Language code, or false for user lang, true for content lang.
1562  * @param $transform Boolean: Whether or not to transform the message.
1563  * @return String: the requested message.
1564  */
1565 function wfMsgReal( $key, $args, $useDB = true, $forContent = false, $transform = true ) {
1566         wfProfileIn( __METHOD__ );
1567         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
1568         $message = wfMsgReplaceArgs( $message, $args );
1569         wfProfileOut( __METHOD__ );
1570         return $message;
1571 }
1572
1573 /**
1574  * Fetch a message string value, but don't replace any keys yet.
1575  *
1576  * @deprecated since 1.18
1577  *
1578  * @param $key String
1579  * @param $useDB Bool
1580  * @param $langCode String: Code of the language to get the message for, or
1581  *                  behaves as a content language switch if it is a boolean.
1582  * @param $transform Boolean: whether to parse magic words, etc.
1583  * @return string
1584  */
1585 function wfMsgGetKey( $key, $useDB = true, $langCode = false, $transform = true ) {
1586         wfRunHooks( 'NormalizeMessageKey', array( &$key, &$useDB, &$langCode, &$transform ) );
1587
1588         $cache = MessageCache::singleton();
1589         $message = $cache->get( $key, $useDB, $langCode );
1590         if( $message === false ) {
1591                 $message = '&lt;' . htmlspecialchars( $key ) . '&gt;';
1592         } elseif ( $transform ) {
1593                 $message = $cache->transform( $message );
1594         }
1595         return $message;
1596 }
1597
1598 /**
1599  * Replace message parameter keys on the given formatted output.
1600  *
1601  * @deprecated since 1.18
1602  *
1603  * @param $message String
1604  * @param $args Array
1605  * @return string
1606  * @private
1607  */
1608 function wfMsgReplaceArgs( $message, $args ) {
1609         # Fix windows line-endings
1610         # Some messages are split with explode("\n", $msg)
1611         $message = str_replace( "\r", '', $message );
1612
1613         // Replace arguments
1614         if ( count( $args ) ) {
1615                 if ( is_array( $args[0] ) ) {
1616                         $args = array_values( $args[0] );
1617                 }
1618                 $replacementKeys = array();
1619                 foreach( $args as $n => $param ) {
1620                         $replacementKeys['$' . ( $n + 1 )] = $param;
1621                 }
1622                 $message = strtr( $message, $replacementKeys );
1623         }
1624
1625         return $message;
1626 }
1627
1628 /**
1629  * Return an HTML-escaped version of a message.
1630  * Parameter replacements, if any, are done *after* the HTML-escaping,
1631  * so parameters may contain HTML (eg links or form controls). Be sure
1632  * to pre-escape them if you really do want plaintext, or just wrap
1633  * the whole thing in htmlspecialchars().
1634  *
1635  * @deprecated since 1.18
1636  *
1637  * @param $key String
1638  * @param string ... parameters
1639  * @return string
1640  */
1641 function wfMsgHtml( $key ) {
1642         $args = func_get_args();
1643         array_shift( $args );
1644         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key ) ), $args );
1645 }
1646
1647 /**
1648  * Return an HTML version of message
1649  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
1650  * so parameters may contain HTML (eg links or form controls). Be sure
1651  * to pre-escape them if you really do want plaintext, or just wrap
1652  * the whole thing in htmlspecialchars().
1653  *
1654  * @deprecated since 1.18
1655  *
1656  * @param $key String
1657  * @param string ... parameters
1658  * @return string
1659  */
1660 function wfMsgWikiHtml( $key ) {
1661         $args = func_get_args();
1662         array_shift( $args );
1663         return wfMsgReplaceArgs(
1664                 MessageCache::singleton()->parse( wfMsgGetKey( $key ), null,
1665                 /* can't be set to false */ true, /* interface */ true )->getText(),
1666                 $args );
1667 }
1668
1669 /**
1670  * Returns message in the requested format
1671  *
1672  * @deprecated since 1.18
1673  *
1674  * @param $key String: key of the message
1675  * @param $options Array: processing rules. Can take the following options:
1676  *   <i>parse</i>: parses wikitext to HTML
1677  *   <i>parseinline</i>: parses wikitext to HTML and removes the surrounding
1678  *       p's added by parser or tidy
1679  *   <i>escape</i>: filters message through htmlspecialchars
1680  *   <i>escapenoentities</i>: same, but allows entity references like &#160; through
1681  *   <i>replaceafter</i>: parameters are substituted after parsing or escaping
1682  *   <i>parsemag</i>: transform the message using magic phrases
1683  *   <i>content</i>: fetch message for content language instead of interface
1684  * Also can accept a single associative argument, of the form 'language' => 'xx':
1685  *   <i>language</i>: Language object or language code to fetch message for
1686  *       (overriden by <i>content</i>).
1687  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
1688  *
1689  * @return String
1690  */
1691 function wfMsgExt( $key, $options ) {
1692         $args = func_get_args();
1693         array_shift( $args );
1694         array_shift( $args );
1695         $options = (array)$options;
1696
1697         foreach( $options as $arrayKey => $option ) {
1698                 if( !preg_match( '/^[0-9]+|language$/', $arrayKey ) ) {
1699                         # An unknown index, neither numeric nor "language"
1700                         wfWarn( "wfMsgExt called with incorrect parameter key $arrayKey", 1, E_USER_WARNING );
1701                 } elseif( preg_match( '/^[0-9]+$/', $arrayKey ) && !in_array( $option,
1702                 array( 'parse', 'parseinline', 'escape', 'escapenoentities',
1703                 'replaceafter', 'parsemag', 'content' ) ) ) {
1704                         # A numeric index with unknown value
1705                         wfWarn( "wfMsgExt called with incorrect parameter $option", 1, E_USER_WARNING );
1706                 }
1707         }
1708
1709         if( in_array( 'content', $options, true ) ) {
1710                 $forContent = true;
1711                 $langCode = true;
1712                 $langCodeObj = null;
1713         } elseif( array_key_exists( 'language', $options ) ) {
1714                 $forContent = false;
1715                 $langCode = wfGetLangObj( $options['language'] );
1716                 $langCodeObj = $langCode;
1717         } else {
1718                 $forContent = false;
1719                 $langCode = false;
1720                 $langCodeObj = null;
1721         }
1722
1723         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
1724
1725         if( !in_array( 'replaceafter', $options, true ) ) {
1726                 $string = wfMsgReplaceArgs( $string, $args );
1727         }
1728
1729         $messageCache = MessageCache::singleton();
1730         $parseInline = in_array( 'parseinline', $options, true );
1731         if( in_array( 'parse', $options, true ) || $parseInline ) {
1732                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj );
1733                 if ( $string instanceof ParserOutput ) {
1734                         $string = $string->getText();
1735                 }
1736
1737                 if ( $parseInline ) {
1738                         $m = array();
1739                         if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
1740                                 $string = $m[1];
1741                         }
1742                 }
1743         } elseif ( in_array( 'parsemag', $options, true ) ) {
1744                 $string = $messageCache->transform( $string,
1745                                 !$forContent, $langCodeObj );
1746         }
1747
1748         if ( in_array( 'escape', $options, true ) ) {
1749                 $string = htmlspecialchars ( $string );
1750         } elseif ( in_array( 'escapenoentities', $options, true ) ) {
1751                 $string = Sanitizer::escapeHtmlAllowEntities( $string );
1752         }
1753
1754         if( in_array( 'replaceafter', $options, true ) ) {
1755                 $string = wfMsgReplaceArgs( $string, $args );
1756         }
1757
1758         return $string;
1759 }
1760
1761 /**
1762  * Since wfMsg() and co suck, they don't return false if the message key they
1763  * looked up didn't exist but a XHTML string, this function checks for the
1764  * nonexistance of messages by checking the MessageCache::get() result directly.
1765  *
1766  * @deprecated since 1.18
1767  *
1768  * @param $key      String: the message key looked up
1769  * @return Boolean True if the message *doesn't* exist.
1770  */
1771 function wfEmptyMsg( $key ) {
1772         return MessageCache::singleton()->get( $key, /*useDB*/true, /*content*/false ) === false;
1773 }
1774
1775 /**
1776  * Throw a debugging exception. This function previously once exited the process,
1777  * but now throws an exception instead, with similar results.
1778  *
1779  * @param $msg String: message shown when dying.
1780  */
1781 function wfDebugDieBacktrace( $msg = '' ) {
1782         throw new MWException( $msg );
1783 }
1784
1785 /**
1786  * Fetch server name for use in error reporting etc.
1787  * Use real server name if available, so we know which machine
1788  * in a server farm generated the current page.
1789  *
1790  * @return string
1791  */
1792 function wfHostname() {
1793         static $host;
1794         if ( is_null( $host ) ) {
1795
1796                 # Hostname overriding
1797                 global $wgOverrideHostname;
1798                 if( $wgOverrideHostname !== false ) {
1799                         # Set static and skip any detection
1800                         $host = $wgOverrideHostname;
1801                         return $host;
1802                 }
1803
1804                 if ( function_exists( 'posix_uname' ) ) {
1805                         // This function not present on Windows
1806                         $uname = posix_uname();
1807                 } else {
1808                         $uname = false;
1809                 }
1810                 if( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1811                         $host = $uname['nodename'];
1812                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1813                         # Windows computer name
1814                         $host = getenv( 'COMPUTERNAME' );
1815                 } else {
1816                         # This may be a virtual server.
1817                         $host = $_SERVER['SERVER_NAME'];
1818                 }
1819         }
1820         return $host;
1821 }
1822
1823 /**
1824  * Returns a HTML comment with the elapsed time since request.
1825  * This method has no side effects.
1826  *
1827  * @return string
1828  */
1829 function wfReportTime() {
1830         global $wgRequestTime, $wgShowHostnames;
1831
1832         $elapsed = microtime( true ) - $wgRequestTime;
1833
1834         return $wgShowHostnames
1835                 ? sprintf( '<!-- Served by %s in %01.3f secs. -->', wfHostname(), $elapsed )
1836                 : sprintf( '<!-- Served in %01.3f secs. -->', $elapsed );
1837 }
1838
1839 /**
1840  * Safety wrapper for debug_backtrace().
1841  *
1842  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
1843  * murky circumstances, which may be triggered in part by stub objects
1844  * or other fancy talkin'.
1845  *
1846  * Will return an empty array if Zend Optimizer is detected or if
1847  * debug_backtrace is disabled, otherwise the output from
1848  * debug_backtrace() (trimmed).
1849  *
1850  * @param $limit int This parameter can be used to limit the number of stack frames returned
1851  *
1852  * @return array of backtrace information
1853  */
1854 function wfDebugBacktrace( $limit = 0 ) {
1855         static $disabled = null;
1856
1857         if( extension_loaded( 'Zend Optimizer' ) ) {
1858                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
1859                 return array();
1860         }
1861
1862         if ( is_null( $disabled ) ) {
1863                 $disabled = false;
1864                 $functions = explode( ',', ini_get( 'disable_functions' ) );
1865                 $functions = array_map( 'trim', $functions );
1866                 $functions = array_map( 'strtolower', $functions );
1867                 if ( in_array( 'debug_backtrace', $functions ) ) {
1868                         wfDebug( "debug_backtrace is in disabled_functions\n" );
1869                         $disabled = true;
1870                 }
1871         }
1872         if ( $disabled ) {
1873                 return array();
1874         }
1875
1876         if ( $limit && version_compare( PHP_VERSION, '5.4.0', '>=' ) ) {
1877                 return array_slice( debug_backtrace( DEBUG_BACKTRACE_PROVIDE_OBJECT, $limit + 1 ), 1 );
1878         } else {
1879                 return array_slice( debug_backtrace(), 1 );
1880         }
1881 }
1882
1883 /**
1884  * Get a debug backtrace as a string
1885  *
1886  * @return string
1887  */
1888 function wfBacktrace() {
1889         global $wgCommandLineMode;
1890
1891         if ( $wgCommandLineMode ) {
1892                 $msg = '';
1893         } else {
1894                 $msg = "<ul>\n";
1895         }
1896         $backtrace = wfDebugBacktrace();
1897         foreach( $backtrace as $call ) {
1898                 if( isset( $call['file'] ) ) {
1899                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
1900                         $file = $f[count( $f ) - 1];
1901                 } else {
1902                         $file = '-';
1903                 }
1904                 if( isset( $call['line'] ) ) {
1905                         $line = $call['line'];
1906                 } else {
1907                         $line = '-';
1908                 }
1909                 if ( $wgCommandLineMode ) {
1910                         $msg .= "$file line $line calls ";
1911                 } else {
1912                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
1913                 }
1914                 if( !empty( $call['class'] ) ) {
1915                         $msg .= $call['class'] . $call['type'];
1916                 }
1917                 $msg .= $call['function'] . '()';
1918
1919                 if ( $wgCommandLineMode ) {
1920                         $msg .= "\n";
1921                 } else {
1922                         $msg .= "</li>\n";
1923                 }
1924         }
1925         if ( $wgCommandLineMode ) {
1926                 $msg .= "\n";
1927         } else {
1928                 $msg .= "</ul>\n";
1929         }
1930
1931         return $msg;
1932 }
1933
1934 /**
1935  * Get the name of the function which called this function
1936  * wfGetCaller( 1 ) is the function with the wfGetCaller() call (ie. __FUNCTION__)
1937  * wfGetCaller( 2 ) [default] is the caller of the function running wfGetCaller()
1938  * wfGetCaller( 3 ) is the parent of that.
1939  *
1940  * @param $level Int
1941  * @return Bool|string
1942  */
1943 function wfGetCaller( $level = 2 ) {
1944         $backtrace = wfDebugBacktrace( $level + 1 );
1945         if ( isset( $backtrace[$level] ) ) {
1946                 return wfFormatStackFrame( $backtrace[$level] );
1947         } else {
1948                 $caller = 'unknown';
1949         }
1950         return $caller;
1951 }
1952
1953 /**
1954  * Return a string consisting of callers in the stack. Useful sometimes
1955  * for profiling specific points.
1956  *
1957  * @param $limit int The maximum depth of the stack frame to return, or false for
1958  *               the entire stack.
1959  * @return String
1960  */
1961 function wfGetAllCallers( $limit = 3 ) {
1962         $trace = array_reverse( wfDebugBacktrace() );
1963         if ( !$limit || $limit > count( $trace ) - 1 ) {
1964                 $limit = count( $trace ) - 1;
1965         }
1966         $trace = array_slice( $trace, -$limit - 1, $limit );
1967         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1968 }
1969
1970 /**
1971  * Return a string representation of frame
1972  *
1973  * @param $frame Array
1974  * @return Bool
1975  */
1976 function wfFormatStackFrame( $frame ) {
1977         return isset( $frame['class'] ) ?
1978                 $frame['class'] . '::' . $frame['function'] :
1979                 $frame['function'];
1980 }
1981
1982
1983 /* Some generic result counters, pulled out of SearchEngine */
1984
1985
1986 /**
1987  * @todo document
1988  *
1989  * @param $offset Int
1990  * @param $limit Int
1991  * @return String
1992  */
1993 function wfShowingResults( $offset, $limit ) {
1994         global $wgLang;
1995         return wfMsgExt(
1996                 'showingresults',
1997                 array( 'parseinline' ),
1998                 $wgLang->formatNum( $limit ),
1999                 $wgLang->formatNum( $offset + 1 )
2000         );
2001 }
2002
2003 /**
2004  * Generate (prev x| next x) (20|50|100...) type links for paging
2005  *
2006  * @param $offset String
2007  * @param $limit Integer
2008  * @param $link String
2009  * @param $query String: optional URL query parameter string
2010  * @param $atend Bool: optional param for specified if this is the last page
2011  * @return String
2012  * @deprecated in 1.19; use Language::viewPrevNext() instead
2013  */
2014 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
2015         wfDeprecated( __METHOD__, '1.19' );
2016
2017         global $wgLang;
2018
2019         $query = wfCgiToArray( $query );
2020
2021         if( is_object( $link ) ) {
2022                 $title = $link;
2023         } else {
2024                 $title = Title::newFromText( $link );
2025                 if( is_null( $title ) ) {
2026                         return false;
2027                 }
2028         }
2029
2030         return $wgLang->viewPrevNext( $title, $offset, $limit, $query, $atend );
2031 }
2032
2033 /**
2034  * Make a list item, used by various special pages
2035  *
2036  * @param $page String Page link
2037  * @param $details String Text between brackets
2038  * @param $oppositedm Boolean   Add the direction mark opposite to your
2039  *                                                              language, to display text properly
2040  * @return String
2041  * @deprecated since 1.19; use Language::specialList() instead
2042  */
2043 function wfSpecialList( $page, $details, $oppositedm = true ) {
2044         wfDeprecated( __METHOD__, '1.19' );
2045
2046         global $wgLang;
2047         return $wgLang->specialList( $page, $details, $oppositedm );
2048 }
2049
2050 /**
2051  * @todo document
2052  * @todo FIXME: We may want to blacklist some broken browsers
2053  *
2054  * @param $force Bool
2055  * @return bool Whereas client accept gzip compression
2056  */
2057 function wfClientAcceptsGzip( $force = false ) {
2058         static $result = null;
2059         if ( $result === null || $force ) {
2060                 $result = false;
2061                 if( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
2062                         # @todo FIXME: We may want to blacklist some broken browsers
2063                         $m = array();
2064                         if( preg_match(
2065                                 '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
2066                                 $_SERVER['HTTP_ACCEPT_ENCODING'],
2067                                 $m )
2068                         )
2069                         {
2070                                 if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
2071                                         $result = false;
2072                                         return $result;
2073                                 }
2074                                 wfDebug( "wfClientAcceptsGzip: client accepts gzip.\n" );
2075                                 $result = true;
2076                         }
2077                 }
2078         }
2079         return $result;
2080 }
2081
2082 /**
2083  * Obtain the offset and limit values from the request string;
2084  * used in special pages
2085  *
2086  * @param $deflimit Int default limit if none supplied
2087  * @param $optionname String Name of a user preference to check against
2088  * @return array
2089  *
2090  */
2091 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
2092         global $wgRequest;
2093         return $wgRequest->getLimitOffset( $deflimit, $optionname );
2094 }
2095
2096 /**
2097  * Escapes the given text so that it may be output using addWikiText()
2098  * without any linking, formatting, etc. making its way through. This
2099  * is achieved by substituting certain characters with HTML entities.
2100  * As required by the callers, "<nowiki>" is not used.
2101  *
2102  * @param $text String: text to be escaped
2103  * @return String
2104  */
2105 function wfEscapeWikiText( $text ) {
2106         $text = strtr( "\n$text", array(
2107                 '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
2108                 '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
2109                 '{' => '&#123;', '|' => '&#124;', '}' => '&#125;',
2110                 "\n#" => "\n&#35;", "\n*" => "\n&#42;",
2111                 "\n:" => "\n&#58;", "\n;" => "\n&#59;",
2112                 '://' => '&#58;//', 'ISBN ' => 'ISBN&#32;', 'RFC ' => 'RFC&#32;',
2113         ) );
2114         return substr( $text, 1 );
2115 }
2116
2117 /**
2118  * Get the current unix timetstamp with microseconds.  Useful for profiling
2119  * @return Float
2120  */
2121 function wfTime() {
2122         return microtime( true );
2123 }
2124
2125 /**
2126  * Sets dest to source and returns the original value of dest
2127  * If source is NULL, it just returns the value, it doesn't set the variable
2128  * If force is true, it will set the value even if source is NULL
2129  *
2130  * @param $dest Mixed
2131  * @param $source Mixed
2132  * @param $force Bool
2133  * @return Mixed
2134  */
2135 function wfSetVar( &$dest, $source, $force = false ) {
2136         $temp = $dest;
2137         if ( !is_null( $source ) || $force ) {
2138                 $dest = $source;
2139         }
2140         return $temp;
2141 }
2142
2143 /**
2144  * As for wfSetVar except setting a bit
2145  *
2146  * @param $dest Int
2147  * @param $bit Int
2148  * @param $state Bool
2149  *
2150  * @return bool
2151  */
2152 function wfSetBit( &$dest, $bit, $state = true ) {
2153         $temp = (bool)( $dest & $bit );
2154         if ( !is_null( $state ) ) {
2155                 if ( $state ) {
2156                         $dest |= $bit;
2157                 } else {
2158                         $dest &= ~$bit;
2159                 }
2160         }
2161         return $temp;
2162 }
2163
2164 /**
2165  * A wrapper around the PHP function var_export().
2166  * Either print it or add it to the regular output ($wgOut).
2167  *
2168  * @param $var mixed A PHP variable to dump.
2169  */
2170 function wfVarDump( $var ) {
2171         global $wgOut;
2172         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
2173         if ( headers_sent() || !isset( $wgOut ) || !is_object( $wgOut ) ) {
2174                 print $s;
2175         } else {
2176                 $wgOut->addHTML( $s );
2177         }
2178 }
2179
2180 /**
2181  * Provide a simple HTTP error.
2182  *
2183  * @param $code Int|String
2184  * @param $label String
2185  * @param $desc String
2186  */
2187 function wfHttpError( $code, $label, $desc ) {
2188         global $wgOut;
2189         $wgOut->disable();
2190         header( "HTTP/1.0 $code $label" );
2191         header( "Status: $code $label" );
2192         $wgOut->sendCacheControl();
2193
2194         header( 'Content-type: text/html; charset=utf-8' );
2195         print "<!doctype html>" .
2196                 '<html><head><title>' .
2197                 htmlspecialchars( $label ) .
2198                 '</title></head><body><h1>' .
2199                 htmlspecialchars( $label ) .
2200                 '</h1><p>' .
2201                 nl2br( htmlspecialchars( $desc ) ) .
2202                 "</p></body></html>\n";
2203 }
2204
2205 /**
2206  * Clear away any user-level output buffers, discarding contents.
2207  *
2208  * Suitable for 'starting afresh', for instance when streaming
2209  * relatively large amounts of data without buffering, or wanting to
2210  * output image files without ob_gzhandler's compression.
2211  *
2212  * The optional $resetGzipEncoding parameter controls suppression of
2213  * the Content-Encoding header sent by ob_gzhandler; by default it
2214  * is left. See comments for wfClearOutputBuffers() for why it would
2215  * be used.
2216  *
2217  * Note that some PHP configuration options may add output buffer
2218  * layers which cannot be removed; these are left in place.
2219  *
2220  * @param $resetGzipEncoding Bool
2221  */
2222 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
2223         if( $resetGzipEncoding ) {
2224                 // Suppress Content-Encoding and Content-Length
2225                 // headers from 1.10+s wfOutputHandler
2226                 global $wgDisableOutputCompression;
2227                 $wgDisableOutputCompression = true;
2228         }
2229         while( $status = ob_get_status() ) {
2230                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
2231                         // Probably from zlib.output_compression or other
2232                         // PHP-internal setting which can't be removed.
2233                         //
2234                         // Give up, and hope the result doesn't break
2235                         // output behavior.
2236                         break;
2237                 }
2238                 if( !ob_end_clean() ) {
2239                         // Could not remove output buffer handler; abort now
2240                         // to avoid getting in some kind of infinite loop.
2241                         break;
2242                 }
2243                 if( $resetGzipEncoding ) {
2244                         if( $status['name'] == 'ob_gzhandler' ) {
2245                                 // Reset the 'Content-Encoding' field set by this handler
2246                                 // so we can start fresh.
2247                                 header_remove( 'Content-Encoding' );
2248                                 break;
2249                         }
2250                 }
2251         }
2252 }
2253
2254 /**
2255  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
2256  *
2257  * Clear away output buffers, but keep the Content-Encoding header
2258  * produced by ob_gzhandler, if any.
2259  *
2260  * This should be used for HTTP 304 responses, where you need to
2261  * preserve the Content-Encoding header of the real result, but
2262  * also need to suppress the output of ob_gzhandler to keep to spec
2263  * and avoid breaking Firefox in rare cases where the headers and
2264  * body are broken over two packets.
2265  */
2266 function wfClearOutputBuffers() {
2267         wfResetOutputBuffers( false );
2268 }
2269
2270 /**
2271  * Converts an Accept-* header into an array mapping string values to quality
2272  * factors
2273  *
2274  * @param $accept String
2275  * @param $def String default
2276  * @return Array
2277  */
2278 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
2279         # No arg means accept anything (per HTTP spec)
2280         if( !$accept ) {
2281                 return array( $def => 1.0 );
2282         }
2283
2284         $prefs = array();
2285
2286         $parts = explode( ',', $accept );
2287
2288         foreach( $parts as $part ) {
2289                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
2290                 $values = explode( ';', trim( $part ) );
2291                 $match = array();
2292                 if ( count( $values ) == 1 ) {
2293                         $prefs[$values[0]] = 1.0;
2294                 } elseif ( preg_match( '/q\s*=\s*(\d*\.\d+)/', $values[1], $match ) ) {
2295                         $prefs[$values[0]] = floatval( $match[1] );
2296                 }
2297         }
2298
2299         return $prefs;
2300 }
2301
2302 /**
2303  * Checks if a given MIME type matches any of the keys in the given
2304  * array. Basic wildcards are accepted in the array keys.
2305  *
2306  * Returns the matching MIME type (or wildcard) if a match, otherwise
2307  * NULL if no match.
2308  *
2309  * @param $type String
2310  * @param $avail Array
2311  * @return string
2312  * @private
2313  */
2314 function mimeTypeMatch( $type, $avail ) {
2315         if( array_key_exists( $type, $avail ) ) {
2316                 return $type;
2317         } else {
2318                 $parts = explode( '/', $type );
2319                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
2320                         return $parts[0] . '/*';
2321                 } elseif( array_key_exists( '*/*', $avail ) ) {
2322                         return '*/*';
2323                 } else {
2324                         return null;
2325                 }
2326         }
2327 }
2328
2329 /**
2330  * Returns the 'best' match between a client's requested internet media types
2331  * and the server's list of available types. Each list should be an associative
2332  * array of type to preference (preference is a float between 0.0 and 1.0).
2333  * Wildcards in the types are acceptable.
2334  *
2335  * @param $cprefs Array: client's acceptable type list
2336  * @param $sprefs Array: server's offered types
2337  * @return string
2338  *
2339  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
2340  * XXX: generalize to negotiate other stuff
2341  */
2342 function wfNegotiateType( $cprefs, $sprefs ) {
2343         $combine = array();
2344
2345         foreach( array_keys( $sprefs ) as $type ) {
2346                 $parts = explode( '/', $type );
2347                 if( $parts[1] != '*' ) {
2348                         $ckey = mimeTypeMatch( $type, $cprefs );
2349                         if( $ckey ) {
2350                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
2351                         }
2352                 }
2353         }
2354
2355         foreach( array_keys( $cprefs ) as $type ) {
2356                 $parts = explode( '/', $type );
2357                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
2358                         $skey = mimeTypeMatch( $type, $sprefs );
2359                         if( $skey ) {
2360                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
2361                         }
2362                 }
2363         }
2364
2365         $bestq = 0;
2366         $besttype = null;
2367
2368         foreach( array_keys( $combine ) as $type ) {
2369                 if( $combine[$type] > $bestq ) {
2370                         $besttype = $type;
2371                         $bestq = $combine[$type];
2372                 }
2373         }
2374
2375         return $besttype;
2376 }
2377
2378 /**
2379  * Reference-counted warning suppression
2380  *
2381  * @param $end Bool
2382  */
2383 function wfSuppressWarnings( $end = false ) {
2384         static $suppressCount = 0;
2385         static $originalLevel = false;
2386
2387         if ( $end ) {
2388                 if ( $suppressCount ) {
2389                         --$suppressCount;
2390                         if ( !$suppressCount ) {
2391                                 error_reporting( $originalLevel );
2392                         }
2393                 }
2394         } else {
2395                 if ( !$suppressCount ) {
2396                         // E_DEPRECATED is undefined in PHP 5.2
2397                         if( !defined( 'E_DEPRECATED' ) ) {
2398                                 define( 'E_DEPRECATED', 8192 );
2399                         }
2400                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE | E_USER_WARNING | E_USER_NOTICE | E_DEPRECATED ) );
2401                 }
2402                 ++$suppressCount;
2403         }
2404 }
2405
2406 /**
2407  * Restore error level to previous value
2408  */
2409 function wfRestoreWarnings() {
2410         wfSuppressWarnings( true );
2411 }
2412
2413 # Autodetect, convert and provide timestamps of various types
2414
2415 /**
2416  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
2417  */
2418 define( 'TS_UNIX', 0 );
2419
2420 /**
2421  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
2422  */
2423 define( 'TS_MW', 1 );
2424
2425 /**
2426  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
2427  */
2428 define( 'TS_DB', 2 );
2429
2430 /**
2431  * RFC 2822 format, for E-mail and HTTP headers
2432  */
2433 define( 'TS_RFC2822', 3 );
2434
2435 /**
2436  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
2437  *
2438  * This is used by Special:Export
2439  */
2440 define( 'TS_ISO_8601', 4 );
2441
2442 /**
2443  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
2444  *
2445  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
2446  *       DateTime tag and page 36 for the DateTimeOriginal and
2447  *       DateTimeDigitized tags.
2448  */
2449 define( 'TS_EXIF', 5 );
2450
2451 /**
2452  * Oracle format time.
2453  */
2454 define( 'TS_ORACLE', 6 );
2455
2456 /**
2457  * Postgres format time.
2458  */
2459 define( 'TS_POSTGRES', 7 );
2460
2461 /**
2462  * DB2 format time
2463  */
2464 define( 'TS_DB2', 8 );
2465
2466 /**
2467  * ISO 8601 basic format with no timezone: 19860209T200000Z.  This is used by ResourceLoader
2468  */
2469 define( 'TS_ISO_8601_BASIC', 9 );
2470
2471 /**
2472  * Get a timestamp string in one of various formats
2473  *
2474  * @param $outputtype Mixed: A timestamp in one of the supported formats, the
2475  *                    function will autodetect which format is supplied and act
2476  *                    accordingly.
2477  * @param $ts Mixed: the timestamp to convert or 0 for the current timestamp
2478  * @return Mixed: String / false The same date in the format specified in $outputtype or false
2479  */
2480 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
2481         $uts = 0;
2482         $da = array();
2483         $strtime = '';
2484
2485         if ( !$ts ) { // We want to catch 0, '', null... but not date strings starting with a letter.
2486                 $uts = time();
2487                 $strtime = "@$uts";
2488         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2489                 # TS_DB
2490         } elseif ( preg_match( '/^(\d{4}):(\d\d):(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2491                 # TS_EXIF
2492         } elseif ( preg_match( '/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/D', $ts, $da ) ) {
2493                 # TS_MW
2494         } elseif ( preg_match( '/^-?\d{1,13}$/D', $ts ) ) {
2495                 # TS_UNIX
2496                 $uts = $ts;
2497                 $strtime = "@$ts"; // http://php.net/manual/en/datetime.formats.compound.php
2498         } elseif ( preg_match( '/^\d{2}-\d{2}-\d{4} \d{2}:\d{2}:\d{2}.\d{6}$/', $ts ) ) {
2499                 # TS_ORACLE // session altered to DD-MM-YYYY HH24:MI:SS.FF6
2500                 $strtime = preg_replace( '/(\d\d)\.(\d\d)\.(\d\d)(\.(\d+))?/', "$1:$2:$3",
2501                                 str_replace( '+00:00', 'UTC', $ts ) );
2502         } elseif ( preg_match( '/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2503                 # TS_ISO_8601
2504         } elseif ( preg_match( '/^(\d{4})(\d{2})(\d{2})T(\d{2})(\d{2})(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2505                 #TS_ISO_8601_BASIC
2506         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d*[\+\- ](\d\d)$/', $ts, $da ) ) {
2507                 # TS_POSTGRES
2508         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d* GMT$/', $ts, $da ) ) {
2509                 # TS_POSTGRES
2510         } elseif (preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.\d\d\d$/', $ts, $da ) ) {
2511                 # TS_DB2
2512         } elseif ( preg_match( '/^[ \t\r\n]*([A-Z][a-z]{2},[ \t\r\n]*)?' . # Day of week
2513                                                         '\d\d?[ \t\r\n]*[A-Z][a-z]{2}[ \t\r\n]*\d{2}(?:\d{2})?' .  # dd Mon yyyy
2514                                                         '[ \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
2515                 # TS_RFC2822, accepting a trailing comment. See http://www.squid-cache.org/mail-archive/squid-users/200307/0122.html / r77171
2516                 # The regex is a superset of rfc2822 for readability
2517                 $strtime = strtok( $ts, ';' );
2518         } 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 ) ) {
2519                 # TS_RFC850
2520                 $strtime = $ts;
2521         } 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 ) ) {
2522                 # asctime
2523                 $strtime = $ts;
2524         } else {
2525                 # Bogus value...
2526                 wfDebug("wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n");
2527
2528                 return false;
2529         }
2530
2531         static $formats = array(
2532                 TS_UNIX => 'U',
2533                 TS_MW => 'YmdHis',
2534                 TS_DB => 'Y-m-d H:i:s',
2535                 TS_ISO_8601 => 'Y-m-d\TH:i:s\Z',
2536                 TS_ISO_8601_BASIC => 'Ymd\THis\Z',
2537                 TS_EXIF => 'Y:m:d H:i:s', // This shouldn't ever be used, but is included for completeness
2538                 TS_RFC2822 => 'D, d M Y H:i:s',
2539                 TS_ORACLE => 'd-m-Y H:i:s.000000', // Was 'd-M-y h.i.s A' . ' +00:00' before r51500
2540                 TS_POSTGRES => 'Y-m-d H:i:s',
2541                 TS_DB2 => 'Y-m-d H:i:s',
2542         );
2543
2544         if ( !isset( $formats[$outputtype] ) ) {
2545                 throw new MWException( 'wfTimestamp() called with illegal output type.' );
2546         }
2547
2548         if ( function_exists( "date_create" ) ) {
2549                 if ( count( $da ) ) {
2550                         $ds = sprintf("%04d-%02d-%02dT%02d:%02d:%02d.00+00:00",
2551                                 (int)$da[1], (int)$da[2], (int)$da[3],
2552                                 (int)$da[4], (int)$da[5], (int)$da[6]);
2553
2554                         $d = date_create( $ds, new DateTimeZone( 'GMT' ) );
2555                 } elseif ( $strtime ) {
2556                         $d = date_create( $strtime, new DateTimeZone( 'GMT' ) );
2557                 } else {
2558                         return false;
2559                 }
2560
2561                 if ( !$d ) {
2562                         wfDebug("wfTimestamp() fed bogus time value: $outputtype; $ts\n");
2563                         return false;
2564                 }
2565
2566                 $output = $d->format( $formats[$outputtype] );
2567         } else {
2568                 if ( count( $da ) ) {
2569                         // Warning! gmmktime() acts oddly if the month or day is set to 0
2570                         // We may want to handle that explicitly at some point
2571                         $uts = gmmktime( (int)$da[4], (int)$da[5], (int)$da[6],
2572                                 (int)$da[2], (int)$da[3], (int)$da[1] );
2573                 } elseif ( $strtime ) {
2574                         $uts = strtotime( $strtime );
2575                 }
2576
2577                 if ( $uts === false ) {
2578                         wfDebug("wfTimestamp() can't parse the timestamp (non 32-bit time? Update php): $outputtype; $ts\n");
2579                         return false;
2580                 }
2581
2582                 if ( TS_UNIX == $outputtype ) {
2583                         return $uts;
2584                 }
2585                 $output = gmdate( $formats[$outputtype], $uts );
2586         }
2587
2588         if ( ( $outputtype == TS_RFC2822 ) || ( $outputtype == TS_POSTGRES ) ) {
2589                 $output .= ' GMT';
2590         }
2591
2592         return $output;
2593 }
2594
2595 /**
2596  * Return a formatted timestamp, or null if input is null.
2597  * For dealing with nullable timestamp columns in the database.
2598  *
2599  * @param $outputtype Integer
2600  * @param $ts String
2601  * @return String
2602  */
2603 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2604         if( is_null( $ts ) ) {
2605                 return null;
2606         } else {
2607                 return wfTimestamp( $outputtype, $ts );
2608         }
2609 }
2610
2611 /**
2612  * Convenience function; returns MediaWiki timestamp for the present time.
2613  *
2614  * @return string
2615  */
2616 function wfTimestampNow() {
2617         # return NOW
2618         return wfTimestamp( TS_MW, time() );
2619 }
2620
2621 /**
2622  * Check if the operating system is Windows
2623  *
2624  * @return Bool: true if it's Windows, False otherwise.
2625  */
2626 function wfIsWindows() {
2627         static $isWindows = null;
2628         if ( $isWindows === null ) {
2629                 $isWindows = substr( php_uname(), 0, 7 ) == 'Windows';
2630         }
2631         return $isWindows;
2632 }
2633
2634 /**
2635  * Check if we are running under HipHop
2636  *
2637  * @return Bool
2638  */
2639 function wfIsHipHop() {
2640         return function_exists( 'hphp_thread_set_warmup_enabled' );
2641 }
2642
2643 /**
2644  * Swap two variables
2645  *
2646  * @param $x Mixed
2647  * @param $y Mixed
2648  */
2649 function swap( &$x, &$y ) {
2650         $z = $x;
2651         $x = $y;
2652         $y = $z;
2653 }
2654
2655 /**
2656  * Tries to get the system directory for temporary files. First
2657  * $wgTmpDirectory is checked, and then the TMPDIR, TMP, and TEMP
2658  * environment variables are then checked in sequence, and if none are
2659  * set try sys_get_temp_dir().
2660  *
2661  * NOTE: When possible, use instead the tmpfile() function to create
2662  * temporary files to avoid race conditions on file creation, etc.
2663  *
2664  * @return String
2665  */
2666 function wfTempDir() {
2667         global $wgTmpDirectory;
2668
2669         if ( $wgTmpDirectory !== false ) {
2670                 return $wgTmpDirectory;
2671         }
2672
2673         $tmpDir = array_map( "getenv", array( 'TMPDIR', 'TMP', 'TEMP' ) );
2674
2675         foreach( $tmpDir as $tmp ) {
2676                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
2677                         return $tmp;
2678                 }
2679         }
2680         return sys_get_temp_dir();
2681 }
2682
2683 /**
2684  * Make directory, and make all parent directories if they don't exist
2685  *
2686  * @param $dir String: full path to directory to create
2687  * @param $mode Integer: chmod value to use, default is $wgDirectoryMode
2688  * @param $caller String: optional caller param for debugging.
2689  * @return bool
2690  */
2691 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2692         global $wgDirectoryMode;
2693
2694         if ( FileBackend::isStoragePath( $dir ) ) { // sanity
2695                 throw new MWException( __FUNCTION__ . " given storage path `$dir`.");
2696         }
2697
2698         if ( !is_null( $caller ) ) {
2699                 wfDebug( "$caller: called wfMkdirParents($dir)\n" );
2700         }
2701
2702         if( strval( $dir ) === '' || file_exists( $dir ) ) {
2703                 return true;
2704         }
2705
2706         $dir = str_replace( array( '\\', '/' ), DIRECTORY_SEPARATOR, $dir );
2707
2708         if ( is_null( $mode ) ) {
2709                 $mode = $wgDirectoryMode;
2710         }
2711
2712         // Turn off the normal warning, we're doing our own below
2713         wfSuppressWarnings();
2714         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2715         wfRestoreWarnings();
2716
2717         if( !$ok ) {
2718                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2719                 trigger_error( sprintf( "%s: failed to mkdir \"%s\" mode 0%o", __FUNCTION__, $dir, $mode ),
2720                         E_USER_WARNING );
2721         }
2722         return $ok;
2723 }
2724
2725 /**
2726  * Remove a directory and all its content.
2727  * Does not hide error.
2728  */
2729 function wfRecursiveRemoveDir( $dir ) {
2730         wfDebug( __FUNCTION__ . "( $dir )\n" );
2731         // taken from http://de3.php.net/manual/en/function.rmdir.php#98622
2732         if ( is_dir( $dir ) ) {
2733                 $objects = scandir( $dir );
2734                 foreach ( $objects as $object ) {
2735                         if ( $object != "." && $object != ".." ) {
2736                                 if ( filetype( $dir . '/' . $object ) == "dir" ) {
2737                                         wfRecursiveRemoveDir( $dir . '/' . $object );
2738                                 } else {
2739                                         unlink( $dir . '/' . $object );
2740                                 }
2741                         }
2742                 }
2743                 reset( $objects );
2744                 rmdir( $dir );
2745         }
2746 }
2747
2748 /**
2749  * @param $nr Mixed: the number to format
2750  * @param $acc Integer: the number of digits after the decimal point, default 2
2751  * @param $round Boolean: whether or not to round the value, default true
2752  * @return float
2753  */
2754 function wfPercent( $nr, $acc = 2, $round = true ) {
2755         $ret = sprintf( "%.${acc}f", $nr );
2756         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2757 }
2758
2759 /**
2760  * Find out whether or not a mixed variable exists in a string
2761  *
2762  * @param $needle String
2763  * @param $str String
2764  * @param $insensitive Boolean
2765  * @return Boolean
2766  */
2767 function in_string( $needle, $str, $insensitive = false ) {
2768         $func = 'strpos';
2769         if( $insensitive ) $func = 'stripos';
2770
2771         return $func( $str, $needle ) !== false;
2772 }
2773
2774 /**
2775  * Safety wrapper around ini_get() for boolean settings.
2776  * The values returned from ini_get() are pre-normalized for settings
2777  * set via php.ini or php_flag/php_admin_flag... but *not*
2778  * for those set via php_value/php_admin_value.
2779  *
2780  * It's fairly common for people to use php_value instead of php_flag,
2781  * which can leave you with an 'off' setting giving a false positive
2782  * for code that just takes the ini_get() return value as a boolean.
2783  *
2784  * To make things extra interesting, setting via php_value accepts
2785  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2786  * Unrecognized values go false... again opposite PHP's own coercion
2787  * from string to bool.
2788  *
2789  * Luckily, 'properly' set settings will always come back as '0' or '1',
2790  * so we only have to worry about them and the 'improper' settings.
2791  *
2792  * I frickin' hate PHP... :P
2793  *
2794  * @param $setting String
2795  * @return Bool
2796  */
2797 function wfIniGetBool( $setting ) {
2798         $val = ini_get( $setting );
2799         // 'on' and 'true' can't have whitespace around them, but '1' can.
2800         return strtolower( $val ) == 'on'
2801                 || strtolower( $val ) == 'true'
2802                 || strtolower( $val ) == 'yes'
2803                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2804 }
2805
2806 /**
2807  * Wrapper function for PHP's dl(). This doesn't work in most situations from
2808  * PHP 5.3 onward, and is usually disabled in shared environments anyway.
2809  *
2810  * @param $extension String A PHP extension. The file suffix (.so or .dll)
2811  *                          should be omitted
2812  * @param $fileName String Name of the library, if not $extension.suffix
2813  * @return Bool - Whether or not the extension is loaded
2814  */
2815 function wfDl( $extension, $fileName = null ) {
2816         if( extension_loaded( $extension ) ) {
2817                 return true;
2818         }
2819
2820         $canDl = false;
2821         $sapi = php_sapi_name();
2822         if( $sapi == 'cli' || $sapi == 'cgi' || $sapi == 'embed' ) {
2823                 $canDl = ( function_exists( 'dl' ) && is_callable( 'dl' )
2824                 && wfIniGetBool( 'enable_dl' ) && !wfIniGetBool( 'safe_mode' ) );
2825         }
2826
2827         if( $canDl ) {
2828                 $fileName = $fileName ? $fileName : $extension;
2829                 if( wfIsWindows() ) {
2830                         $fileName = 'php_' . $fileName;
2831                 }
2832                 wfSuppressWarnings();
2833                 dl( $fileName . '.' . PHP_SHLIB_SUFFIX );
2834                 wfRestoreWarnings();
2835         }
2836         return extension_loaded( $extension );
2837 }
2838
2839 /**
2840  * Windows-compatible version of escapeshellarg()
2841  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
2842  * function puts single quotes in regardless of OS.
2843  *
2844  * Also fixes the locale problems on Linux in PHP 5.2.6+ (bug backported to
2845  * earlier distro releases of PHP)
2846  *
2847  * @param varargs
2848  * @return String
2849  */
2850 function wfEscapeShellArg( ) {
2851         wfInitShellLocale();
2852
2853         $args = func_get_args();
2854         $first = true;
2855         $retVal = '';
2856         foreach ( $args as $arg ) {
2857                 if ( !$first ) {
2858                         $retVal .= ' ';
2859                 } else {
2860                         $first = false;
2861                 }
2862
2863                 if ( wfIsWindows() ) {
2864                         // Escaping for an MSVC-style command line parser and CMD.EXE
2865                         // Refs:
2866                         //  * http://web.archive.org/web/20020708081031/http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
2867                         //  * http://technet.microsoft.com/en-us/library/cc723564.aspx
2868                         //  * Bug #13518
2869                         //  * CR r63214
2870                         // Double the backslashes before any double quotes. Escape the double quotes.
2871                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
2872                         $arg = '';
2873                         $iteration = 0;
2874                         foreach ( $tokens as $token ) {
2875                                 if ( $iteration % 2 == 1 ) {
2876                                         // Delimiter, a double quote preceded by zero or more slashes
2877                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
2878                                 } elseif ( $iteration % 4 == 2 ) {
2879                                         // ^ in $token will be outside quotes, need to be escaped
2880                                         $arg .= str_replace( '^', '^^', $token );
2881                                 } else { // $iteration % 4 == 0
2882                                         // ^ in $token will appear inside double quotes, so leave as is
2883                                         $arg .= $token;
2884                                 }
2885                                 $iteration++;
2886                         }
2887                         // Double the backslashes before the end of the string, because
2888                         // we will soon add a quote
2889                         $m = array();
2890                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
2891                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
2892                         }
2893
2894                         // Add surrounding quotes
2895                         $retVal .= '"' . $arg . '"';
2896                 } else {
2897                         $retVal .= escapeshellarg( $arg );
2898                 }
2899         }
2900         return $retVal;
2901 }
2902
2903 /**
2904  * Execute a shell command, with time and memory limits mirrored from the PHP
2905  * configuration if supported.
2906  * @param $cmd String Command line, properly escaped for shell.
2907  * @param &$retval null|Mixed optional, will receive the program's exit code.
2908  *                 (non-zero is usually failure)
2909  * @param $environ Array optional environment variables which should be
2910  *                 added to the executed command environment.
2911  * @param $limits Array optional array with limits(filesize, memory, time)
2912  *                 this overwrites the global wgShellMax* limits.
2913  * @return string collected stdout as a string (trailing newlines stripped)
2914  */
2915 function wfShellExec( $cmd, &$retval = null, $environ = array(), $limits = array() ) {
2916         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize, $wgMaxShellTime;
2917
2918         static $disabled;
2919         if ( is_null( $disabled ) ) {
2920                 $disabled = false;
2921                 if( wfIniGetBool( 'safe_mode' ) ) {
2922                         wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
2923                         $disabled = 'safemode';
2924                 } else {
2925                         $functions = explode( ',', ini_get( 'disable_functions' ) );
2926                         $functions = array_map( 'trim', $functions );
2927                         $functions = array_map( 'strtolower', $functions );
2928                         if ( in_array( 'passthru', $functions ) ) {
2929                                 wfDebug( "passthru is in disabled_functions\n" );
2930                                 $disabled = 'passthru';
2931                         }
2932                 }
2933         }
2934         if ( $disabled ) {
2935                 $retval = 1;
2936                 return $disabled == 'safemode' ?
2937                         'Unable to run external programs in safe mode.' :
2938                         'Unable to run external programs, passthru() is disabled.';
2939         }
2940
2941         wfInitShellLocale();
2942
2943         $envcmd = '';
2944         foreach( $environ as $k => $v ) {
2945                 if ( wfIsWindows() ) {
2946                         /* Surrounding a set in quotes (method used by wfEscapeShellArg) makes the quotes themselves
2947                          * appear in the environment variable, so we must use carat escaping as documented in
2948                          * http://technet.microsoft.com/en-us/library/cc723564.aspx
2949                          * Note however that the quote isn't listed there, but is needed, and the parentheses
2950                          * are listed there but doesn't appear to need it.
2951                          */
2952                         $envcmd .= "set $k=" . preg_replace( '/([&|()<>^"])/', '^\\1', $v ) . '&& ';
2953                 } else {
2954                         /* Assume this is a POSIX shell, thus required to accept variable assignments before the command
2955                          * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_09_01
2956                          */
2957                         $envcmd .= "$k=" . escapeshellarg( $v ) . ' ';
2958                 }
2959         }
2960         $cmd = $envcmd . $cmd;
2961
2962         if ( php_uname( 's' ) == 'Linux' ) {
2963                 $time = intval ( isset($limits['time']) ? $limits['time'] : $wgMaxShellTime );
2964                 $mem = intval ( isset($limits['memory']) ? $limits['memory'] : $wgMaxShellMemory );
2965                 $filesize = intval ( isset($limits['filesize']) ? $limits['filesize'] : $wgMaxShellFileSize );
2966
2967                 if ( $time > 0 && $mem > 0 ) {
2968                         $script = "$IP/bin/ulimit4.sh";
2969                         if ( is_executable( $script ) ) {
2970                                 $cmd = '/bin/bash ' . escapeshellarg( $script ) . " $time $mem $filesize " . escapeshellarg( $cmd );
2971                         }
2972                 }
2973         }
2974         wfDebug( "wfShellExec: $cmd\n" );
2975
2976         $retval = 1; // error by default?
2977         ob_start();
2978         passthru( $cmd, $retval );
2979         $output = ob_get_contents();
2980         ob_end_clean();
2981
2982         if ( $retval == 127 ) {
2983                 wfDebugLog( 'exec', "Possibly missing executable file: $cmd\n" );
2984         }
2985         return $output;
2986 }
2987
2988 /**
2989  * Workaround for http://bugs.php.net/bug.php?id=45132
2990  * escapeshellarg() destroys non-ASCII characters if LANG is not a UTF-8 locale
2991  */
2992 function wfInitShellLocale() {
2993         static $done = false;
2994         if ( $done ) {
2995                 return;
2996         }
2997         $done = true;
2998         global $wgShellLocale;
2999         if ( !wfIniGetBool( 'safe_mode' ) ) {
3000                 putenv( "LC_CTYPE=$wgShellLocale" );
3001                 setlocale( LC_CTYPE, $wgShellLocale );
3002         }
3003 }
3004
3005 /**
3006  * Alias to wfShellWikiCmd()
3007  * @see wfShellWikiCmd()
3008  */
3009 function wfShellMaintenanceCmd( $script, array $parameters = array(), array $options = array() ) {
3010         return wfShellWikiCmd( $script, $parameters, $options );
3011 }
3012
3013 /**
3014  * Generate a shell-escaped command line string to run a MediaWiki cli script.
3015  * Note that $parameters should be a flat array and an option with an argument
3016  * should consist of two consecutive items in the array (do not use "--option value").
3017  * @param $script string MediaWiki cli script path
3018  * @param $parameters Array Arguments and options to the script
3019  * @param $options Array Associative array of options:
3020  *              'php': The path to the php executable
3021  *              'wrapper': Path to a PHP wrapper to handle the maintenance script
3022  * @return Array
3023  */
3024 function wfShellWikiCmd( $script, array $parameters = array(), array $options = array() ) {
3025         global $wgPhpCli;
3026         // Give site config file a chance to run the script in a wrapper.
3027         // The caller may likely want to call wfBasename() on $script.
3028         wfRunHooks( 'wfShellWikiCmd', array( &$script, &$parameters, &$options ) );
3029         $cmd = isset( $options['php'] ) ? array( $options['php'] ) : array( $wgPhpCli );
3030         if ( isset( $options['wrapper'] ) ) {
3031                 $cmd[] = $options['wrapper'];
3032         }
3033         $cmd[] = $script;
3034         // Escape each parameter for shell
3035         return implode( " ", array_map( 'wfEscapeShellArg', array_merge( $cmd, $parameters ) ) );
3036 }
3037
3038 /**
3039  * wfMerge attempts to merge differences between three texts.
3040  * Returns true for a clean merge and false for failure or a conflict.
3041  *
3042  * @param $old String
3043  * @param $mine String
3044  * @param $yours String
3045  * @param $result String
3046  * @return Bool
3047  */
3048 function wfMerge( $old, $mine, $yours, &$result ) {
3049         global $wgDiff3;
3050
3051         # This check may also protect against code injection in
3052         # case of broken installations.
3053         wfSuppressWarnings();
3054         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
3055         wfRestoreWarnings();
3056
3057         if( !$haveDiff3 ) {
3058                 wfDebug( "diff3 not found\n" );
3059                 return false;
3060         }
3061
3062         # Make temporary files
3063         $td = wfTempDir();
3064         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
3065         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
3066         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
3067
3068         fwrite( $oldtextFile, $old );
3069         fclose( $oldtextFile );
3070         fwrite( $mytextFile, $mine );
3071         fclose( $mytextFile );
3072         fwrite( $yourtextFile, $yours );
3073         fclose( $yourtextFile );
3074
3075         # Check for a conflict
3076         $cmd = $wgDiff3 . ' -a --overlap-only ' .
3077                 wfEscapeShellArg( $mytextName ) . ' ' .
3078                 wfEscapeShellArg( $oldtextName ) . ' ' .
3079                 wfEscapeShellArg( $yourtextName );
3080         $handle = popen( $cmd, 'r' );
3081
3082         if( fgets( $handle, 1024 ) ) {
3083                 $conflict = true;
3084         } else {
3085                 $conflict = false;
3086         }
3087         pclose( $handle );
3088
3089         # Merge differences
3090         $cmd = $wgDiff3 . ' -a -e --merge ' .
3091                 wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
3092         $handle = popen( $cmd, 'r' );
3093         $result = '';
3094         do {
3095                 $data = fread( $handle, 8192 );
3096                 if ( strlen( $data ) == 0 ) {
3097                         break;
3098                 }
3099                 $result .= $data;
3100         } while ( true );
3101         pclose( $handle );
3102         unlink( $mytextName );
3103         unlink( $oldtextName );
3104         unlink( $yourtextName );
3105
3106         if ( $result === '' && $old !== '' && !$conflict ) {
3107                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
3108                 $conflict = true;
3109         }
3110         return !$conflict;
3111 }
3112
3113 /**
3114  * Returns unified plain-text diff of two texts.
3115  * Useful for machine processing of diffs.
3116  *
3117  * @param $before String: the text before the changes.
3118  * @param $after String: the text after the changes.
3119  * @param $params String: command-line options for the diff command.
3120  * @return String: unified diff of $before and $after
3121  */
3122 function wfDiff( $before, $after, $params = '-u' ) {
3123         if ( $before == $after ) {
3124                 return '';
3125         }
3126
3127         global $wgDiff;
3128         wfSuppressWarnings();
3129         $haveDiff = $wgDiff && file_exists( $wgDiff );
3130         wfRestoreWarnings();
3131
3132         # This check may also protect against code injection in
3133         # case of broken installations.
3134         if( !$haveDiff ) {
3135                 wfDebug( "diff executable not found\n" );
3136                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
3137                 $format = new UnifiedDiffFormatter();
3138                 return $format->format( $diffs );
3139         }
3140
3141         # Make temporary files
3142         $td = wfTempDir();
3143         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
3144         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
3145
3146         fwrite( $oldtextFile, $before );
3147         fclose( $oldtextFile );
3148         fwrite( $newtextFile, $after );
3149         fclose( $newtextFile );
3150
3151         // Get the diff of the two files
3152         $cmd = "$wgDiff " . $params . ' ' . wfEscapeShellArg( $oldtextName, $newtextName );
3153
3154         $h = popen( $cmd, 'r' );
3155
3156         $diff = '';
3157
3158         do {
3159                 $data = fread( $h, 8192 );
3160                 if ( strlen( $data ) == 0 ) {
3161                         break;
3162                 }
3163                 $diff .= $data;
3164         } while ( true );
3165
3166         // Clean up
3167         pclose( $h );
3168         unlink( $oldtextName );
3169         unlink( $newtextName );
3170
3171         // Kill the --- and +++ lines. They're not useful.
3172         $diff_lines = explode( "\n", $diff );
3173         if ( strpos( $diff_lines[0], '---' ) === 0 ) {
3174                 unset( $diff_lines[0] );
3175         }
3176         if ( strpos( $diff_lines[1], '+++' ) === 0 ) {
3177                 unset( $diff_lines[1] );
3178         }
3179
3180         $diff = implode( "\n", $diff_lines );
3181
3182         return $diff;
3183 }
3184
3185 /**
3186  * This function works like "use VERSION" in Perl, the program will die with a
3187  * backtrace if the current version of PHP is less than the version provided
3188  *
3189  * This is useful for extensions which due to their nature are not kept in sync
3190  * with releases, and might depend on other versions of PHP than the main code
3191  *
3192  * Note: PHP might die due to parsing errors in some cases before it ever
3193  *       manages to call this function, such is life
3194  *
3195  * @see perldoc -f use
3196  *
3197  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
3198  *                 a float
3199  */
3200 function wfUsePHP( $req_ver ) {
3201         $php_ver = PHP_VERSION;
3202
3203         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
3204                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
3205         }
3206 }
3207
3208 /**
3209  * This function works like "use VERSION" in Perl except it checks the version
3210  * of MediaWiki, the program will die with a backtrace if the current version
3211  * of MediaWiki is less than the version provided.
3212  *
3213  * This is useful for extensions which due to their nature are not kept in sync
3214  * with releases
3215  *
3216  * @see perldoc -f use
3217  *
3218  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
3219  *                 a float
3220  */
3221 function wfUseMW( $req_ver ) {
3222         global $wgVersion;
3223
3224         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
3225                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
3226         }
3227 }
3228
3229 /**
3230  * Return the final portion of a pathname.
3231  * Reimplemented because PHP5's "basename()" is buggy with multibyte text.
3232  * http://bugs.php.net/bug.php?id=33898
3233  *
3234  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
3235  * We'll consider it so always, as we don't want '\s' in our Unix paths either.
3236  *
3237  * @param $path String
3238  * @param $suffix String: to remove if present
3239  * @return String
3240  */
3241 function wfBaseName( $path, $suffix = '' ) {
3242         $encSuffix = ( $suffix == '' )
3243                 ? ''
3244                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
3245         $matches = array();
3246         if( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
3247                 return $matches[1];
3248         } else {
3249                 return '';
3250         }
3251 }
3252
3253 /**
3254  * Generate a relative path name to the given file.
3255  * May explode on non-matching case-insensitive paths,
3256  * funky symlinks, etc.
3257  *
3258  * @param $path String: absolute destination path including target filename
3259  * @param $from String: Absolute source path, directory only
3260  * @return String
3261  */
3262 function wfRelativePath( $path, $from ) {
3263         // Normalize mixed input on Windows...
3264         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
3265         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
3266
3267         // Trim trailing slashes -- fix for drive root
3268         $path = rtrim( $path, DIRECTORY_SEPARATOR );
3269         $from = rtrim( $from, DIRECTORY_SEPARATOR );
3270
3271         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
3272         $against = explode( DIRECTORY_SEPARATOR, $from );
3273
3274         if( $pieces[0] !== $against[0] ) {
3275                 // Non-matching Windows drive letters?
3276                 // Return a full path.
3277                 return $path;
3278         }
3279
3280         // Trim off common prefix
3281         while( count( $pieces ) && count( $against )
3282                 && $pieces[0] == $against[0] ) {
3283                 array_shift( $pieces );
3284                 array_shift( $against );
3285         }
3286
3287         // relative dots to bump us to the parent
3288         while( count( $against ) ) {
3289                 array_unshift( $pieces, '..' );
3290                 array_shift( $against );
3291         }
3292
3293         array_push( $pieces, wfBaseName( $path ) );
3294
3295         return implode( DIRECTORY_SEPARATOR, $pieces );
3296 }
3297
3298 /**
3299  * Do any deferred updates and clear the list
3300  *
3301  * @deprecated since 1.19
3302  * @see DeferredUpdates::doUpdate()
3303  * @param $commit string
3304  */
3305 function wfDoUpdates( $commit = '' ) {
3306         wfDeprecated( __METHOD__, '1.19' );
3307         DeferredUpdates::doUpdates( $commit );
3308 }
3309
3310 /**
3311  * Convert an arbitrarily-long digit string from one numeric base
3312  * to another, optionally zero-padding to a minimum column width.
3313  *
3314  * Supports base 2 through 36; digit values 10-36 are represented
3315  * as lowercase letters a-z. Input is case-insensitive.
3316  *
3317  * @param $input String: of digits
3318  * @param $sourceBase Integer: 2-36
3319  * @param $destBase Integer: 2-36
3320  * @param $pad Integer: 1 or greater
3321  * @param $lowercase Boolean
3322  * @return String or false on invalid input
3323  */
3324 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1, $lowercase = true ) {
3325         $input = strval( $input );
3326         if( $sourceBase < 2 ||
3327                 $sourceBase > 36 ||
3328                 $destBase < 2 ||
3329                 $destBase > 36 ||
3330                 $pad < 1 ||
3331                 $sourceBase != intval( $sourceBase ) ||
3332                 $destBase != intval( $destBase ) ||
3333                 $pad != intval( $pad ) ||
3334                 !is_string( $input ) ||
3335                 $input == '' ) {
3336                 return false;
3337         }
3338         $digitChars = ( $lowercase ) ? '0123456789abcdefghijklmnopqrstuvwxyz' : '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
3339         $inDigits = array();
3340         $outChars = '';
3341
3342         // Decode and validate input string
3343         $input = strtolower( $input );
3344         for( $i = 0; $i < strlen( $input ); $i++ ) {
3345                 $n = strpos( $digitChars, $input[$i] );
3346                 if( $n === false || $n > $sourceBase ) {
3347                         return false;
3348                 }
3349                 $inDigits[] = $n;
3350         }
3351
3352         // Iterate over the input, modulo-ing out an output digit
3353         // at a time until input is gone.
3354         while( count( $inDigits ) ) {
3355                 $work = 0;
3356                 $workDigits = array();
3357
3358                 // Long division...
3359                 foreach( $inDigits as $digit ) {
3360                         $work *= $sourceBase;
3361                         $work += $digit;
3362
3363                         if( $work < $destBase ) {
3364                                 // Gonna need to pull another digit.
3365                                 if( count( $workDigits ) ) {
3366                                         // Avoid zero-padding; this lets us find
3367                                         // the end of the input very easily when
3368                                         // length drops to zero.
3369                                         $workDigits[] = 0;
3370                                 }
3371                         } else {
3372                                 // Finally! Actual division!
3373                                 $workDigits[] = intval( $work / $destBase );
3374
3375                                 // Isn't it annoying that most programming languages
3376                                 // don't have a single divide-and-remainder operator,
3377                                 // even though the CPU implements it that way?
3378                                 $work = $work % $destBase;
3379                         }
3380                 }
3381
3382                 // All that division leaves us with a remainder,
3383                 // which is conveniently our next output digit.
3384                 $outChars .= $digitChars[$work];
3385
3386                 // And we continue!
3387                 $inDigits = $workDigits;
3388         }
3389
3390         while( strlen( $outChars ) < $pad ) {
3391                 $outChars .= '0';
3392         }
3393
3394         return strrev( $outChars );
3395 }
3396
3397 /**
3398  * Create an object with a given name and an array of construct parameters
3399  *
3400  * @param $name String
3401  * @param $p Array: parameters
3402  * @return object
3403  * @deprecated since 1.18, warnings in 1.18, removal in 1.20
3404  */
3405 function wfCreateObject( $name, $p ) {
3406         wfDeprecated( __FUNCTION__, '1.18' );
3407         return MWFunction::newObj( $name, $p );
3408 }
3409
3410 /**
3411  * @return bool
3412  */
3413 function wfHttpOnlySafe() {
3414         global $wgHttpOnlyBlacklist;
3415
3416         if( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
3417                 foreach( $wgHttpOnlyBlacklist as $regex ) {
3418                         if( preg_match( $regex, $_SERVER['HTTP_USER_AGENT'] ) ) {
3419                                 return false;
3420                         }
3421                 }
3422         }
3423
3424         return true;
3425 }
3426
3427 /**
3428  * Override session_id before session startup if php's built-in
3429  * session generation code is not secure.
3430  */
3431 function wfFixSessionID() {
3432         // If the cookie or session id is already set we already have a session and should abort
3433         if ( isset( $_COOKIE[ session_name() ] ) || session_id() ) {
3434                 return;
3435         }
3436
3437         // PHP's built-in session entropy is enabled if:
3438         // - entropy_file is set or you're on Windows with php 5.3.3+
3439         // - AND entropy_length is > 0
3440         // We treat it as disabled if it doesn't have an entropy length of at least 32
3441         $entropyEnabled = (
3442                         ( wfIsWindows() && version_compare( PHP_VERSION, '5.3.3', '>=' ) )
3443                         || ini_get( 'session.entropy_file' )
3444                 )
3445                 && intval( ini_get( 'session.entropy_length' ) ) >= 32;
3446
3447         // If built-in entropy is not enabled or not sufficient override php's built in session id generation code
3448         if ( !$entropyEnabled ) {
3449                 wfDebug( __METHOD__ . ": PHP's built in entropy is disabled or not sufficient, overriding session id generation using our cryptrand source.\n" );
3450                 session_id( MWCryptRand::generateHex( 32 ) );
3451         }
3452 }
3453
3454 /**
3455  * Initialise php session
3456  *
3457  * @param $sessionId Bool
3458  */
3459 function wfSetupSession( $sessionId = false ) {
3460         global $wgSessionsInMemcached, $wgCookiePath, $wgCookieDomain,
3461                         $wgCookieSecure, $wgCookieHttpOnly, $wgSessionHandler;
3462         if( $wgSessionsInMemcached ) {
3463                 if ( !defined( 'MW_COMPILED' ) ) {
3464                         global $IP;
3465                         require_once( "$IP/includes/cache/MemcachedSessions.php" );
3466                 }
3467                 session_set_save_handler( 'memsess_open', 'memsess_close', 'memsess_read',
3468                         'memsess_write', 'memsess_destroy', 'memsess_gc' );
3469
3470                 // It's necessary to register a shutdown function to call session_write_close(),
3471                 // because by the time the request shutdown function for the session module is
3472                 // called, $wgMemc has already been destroyed. Shutdown functions registered
3473                 // this way are called before object destruction.
3474                 register_shutdown_function( 'memsess_write_close' );
3475         } elseif( $wgSessionHandler && $wgSessionHandler != ini_get( 'session.save_handler' ) ) {
3476                 # Only set this if $wgSessionHandler isn't null and session.save_handler
3477                 # hasn't already been set to the desired value (that causes errors)
3478                 ini_set( 'session.save_handler', $wgSessionHandler );
3479         }
3480         $httpOnlySafe = wfHttpOnlySafe() && $wgCookieHttpOnly;
3481         wfDebugLog( 'cookie',
3482                 'session_set_cookie_params: "' . implode( '", "',
3483                         array(
3484                                 0,
3485                                 $wgCookiePath,
3486                                 $wgCookieDomain,
3487                                 $wgCookieSecure,
3488                                 $httpOnlySafe ) ) . '"' );
3489         session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $httpOnlySafe );
3490         session_cache_limiter( 'private, must-revalidate' );
3491         if ( $sessionId ) {
3492                 session_id( $sessionId );
3493         } else {
3494                 wfFixSessionID();
3495         }
3496         wfSuppressWarnings();
3497         session_start();
3498         wfRestoreWarnings();
3499 }
3500
3501 /**
3502  * Get an object from the precompiled serialized directory
3503  *
3504  * @param $name String
3505  * @return Mixed: the variable on success, false on failure
3506  */
3507 function wfGetPrecompiledData( $name ) {
3508         global $IP;
3509
3510         $file = "$IP/serialized/$name";
3511         if ( file_exists( $file ) ) {
3512                 $blob = file_get_contents( $file );
3513                 if ( $blob ) {
3514                         return unserialize( $blob );
3515                 }
3516         }
3517         return false;
3518 }
3519
3520 /**
3521  * Get a cache key
3522  *
3523  * @param varargs
3524  * @return String
3525  */
3526 function wfMemcKey( /*... */ ) {
3527         global $wgCachePrefix;
3528         $prefix = $wgCachePrefix === false ? wfWikiID() : $wgCachePrefix;
3529         $args = func_get_args();
3530         $key = $prefix . ':' . implode( ':', $args );
3531         $key = str_replace( ' ', '_', $key );
3532         return $key;
3533 }
3534
3535 /**
3536  * Get a cache key for a foreign DB
3537  *
3538  * @param $db String
3539  * @param $prefix String
3540  * @param varargs String
3541  * @return String
3542  */
3543 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
3544         $args = array_slice( func_get_args(), 2 );
3545         if ( $prefix ) {
3546                 $key = "$db-$prefix:" . implode( ':', $args );
3547         } else {
3548                 $key = $db . ':' . implode( ':', $args );
3549         }
3550         return $key;
3551 }
3552
3553 /**
3554  * Get an ASCII string identifying this wiki
3555  * This is used as a prefix in memcached keys
3556  *
3557  * @return String
3558  */
3559 function wfWikiID() {
3560         global $wgDBprefix, $wgDBname;
3561         if ( $wgDBprefix ) {
3562                 return "$wgDBname-$wgDBprefix";
3563         } else {
3564                 return $wgDBname;
3565         }
3566 }
3567
3568 /**
3569  * Split a wiki ID into DB name and table prefix
3570  *
3571  * @param $wiki String
3572  *
3573  * @return array
3574  */
3575 function wfSplitWikiID( $wiki ) {
3576         $bits = explode( '-', $wiki, 2 );
3577         if ( count( $bits ) < 2 ) {
3578                 $bits[] = '';
3579         }
3580         return $bits;
3581 }
3582
3583 /**
3584  * Get a Database object.
3585  *
3586  * @param $db Integer: index of the connection to get. May be DB_MASTER for the
3587  *            master (for write queries), DB_SLAVE for potentially lagged read
3588  *            queries, or an integer >= 0 for a particular server.
3589  *
3590  * @param $groups Mixed: query groups. An array of group names that this query
3591  *                belongs to. May contain a single string if the query is only
3592  *                in one group.
3593  *
3594  * @param $wiki String: the wiki ID, or false for the current wiki
3595  *
3596  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
3597  * will always return the same object, unless the underlying connection or load
3598  * balancer is manually destroyed.
3599  *
3600  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
3601  * updater to ensure that a proper database is being updated.
3602  *
3603  * @return DatabaseBase
3604  */
3605 function &wfGetDB( $db, $groups = array(), $wiki = false ) {
3606         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
3607 }
3608
3609 /**
3610  * Get a load balancer object.
3611  *
3612  * @param $wiki String: wiki ID, or false for the current wiki
3613  * @return LoadBalancer
3614  */
3615 function wfGetLB( $wiki = false ) {
3616         return wfGetLBFactory()->getMainLB( $wiki );
3617 }
3618
3619 /**
3620  * Get the load balancer factory object
3621  *
3622  * @return LBFactory
3623  */
3624 function &wfGetLBFactory() {
3625         return LBFactory::singleton();
3626 }
3627
3628 /**
3629  * Find a file.
3630  * Shortcut for RepoGroup::singleton()->findFile()
3631  *
3632  * @param $title String or Title object
3633  * @param $options array Associative array of options:
3634  *     time:           requested time for an archived image, or false for the
3635  *                     current version. An image object will be returned which was
3636  *                     created at the specified time.
3637  *
3638  *     ignoreRedirect: If true, do not follow file redirects
3639  *
3640  *     private:        If true, return restricted (deleted) files if the current
3641  *                     user is allowed to view them. Otherwise, such files will not
3642  *                     be found.
3643  *
3644  *     bypassCache:    If true, do not use the process-local cache of File objects
3645  *
3646  * @return File, or false if the file does not exist
3647  */
3648 function wfFindFile( $title, $options = array() ) {
3649         return RepoGroup::singleton()->findFile( $title, $options );
3650 }
3651
3652 /**
3653  * Get an object referring to a locally registered file.
3654  * Returns a valid placeholder object if the file does not exist.
3655  *
3656  * @param $title Title|String
3657  * @return LocalFile|null A File, or null if passed an invalid Title
3658  */
3659 function wfLocalFile( $title ) {
3660         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
3661 }
3662
3663 /**
3664  * Stream a file to the browser. Back-compat alias for StreamFile::stream()
3665  * @deprecated since 1.19
3666  */
3667 function wfStreamFile( $fname, $headers = array() ) {
3668         wfDeprecated( __FUNCTION__, '1.19' );
3669         StreamFile::stream( $fname, $headers );
3670 }
3671
3672 /**
3673  * Should low-performance queries be disabled?
3674  *
3675  * @return Boolean
3676  * @codeCoverageIgnore
3677  */
3678 function wfQueriesMustScale() {
3679         global $wgMiserMode;
3680         return $wgMiserMode
3681                 || ( SiteStats::pages() > 100000
3682                 && SiteStats::edits() > 1000000
3683                 && SiteStats::users() > 10000 );
3684 }
3685
3686 /**
3687  * Get the path to a specified script file, respecting file
3688  * extensions; this is a wrapper around $wgScriptExtension etc.
3689  *
3690  * @param $script String: script filename, sans extension
3691  * @return String
3692  */
3693 function wfScript( $script = 'index' ) {
3694         global $wgScriptPath, $wgScriptExtension;
3695         return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
3696 }
3697
3698 /**
3699  * Get the script URL.
3700  *
3701  * @return string script URL
3702  */
3703 function wfGetScriptUrl() {
3704         if( isset( $_SERVER['SCRIPT_NAME'] ) ) {
3705                 #
3706                 # as it was called, minus the query string.
3707                 #
3708                 # Some sites use Apache rewrite rules to handle subdomains,
3709                 # and have PHP set up in a weird way that causes PHP_SELF
3710                 # to contain the rewritten URL instead of the one that the
3711                 # outside world sees.
3712                 #
3713                 # If in this mode, use SCRIPT_URL instead, which mod_rewrite
3714                 # provides containing the "before" URL.
3715                 return $_SERVER['SCRIPT_NAME'];
3716         } else {
3717                 return $_SERVER['URL'];
3718         }
3719 }
3720
3721 /**
3722  * Convenience function converts boolean values into "true"
3723  * or "false" (string) values
3724  *
3725  * @param $value Boolean
3726  * @return String
3727  */
3728 function wfBoolToStr( $value ) {
3729         return $value ? 'true' : 'false';
3730 }
3731
3732 /**
3733  * Load an extension messages file
3734  *
3735  * @deprecated since 1.16, warnings in 1.18, remove in 1.20
3736  * @codeCoverageIgnore
3737  */
3738 function wfLoadExtensionMessages() {
3739         wfDeprecated( __FUNCTION__, '1.16' );
3740 }
3741
3742 /**
3743  * Get a platform-independent path to the null file, e.g. /dev/null
3744  *
3745  * @return string
3746  */
3747 function wfGetNull() {
3748         return wfIsWindows()
3749                 ? 'NUL'
3750                 : '/dev/null';
3751 }
3752
3753 /**
3754  * Modern version of wfWaitForSlaves(). Instead of looking at replication lag
3755  * and waiting for it to go down, this waits for the slaves to catch up to the
3756  * master position. Use this when updating very large numbers of rows, as
3757  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
3758  * a no-op if there are no slaves.
3759  *
3760  * @param $maxLag Integer (deprecated)
3761  * @param $wiki mixed Wiki identifier accepted by wfGetLB
3762  */
3763 function wfWaitForSlaves( $maxLag = false, $wiki = false ) {
3764         $lb = wfGetLB( $wiki );
3765         // bug 27975 - Don't try to wait for slaves if there are none
3766         // Prevents permission error when getting master position
3767         if ( $lb->getServerCount() > 1 ) {
3768                 $dbw = $lb->getConnection( DB_MASTER );
3769                 $pos = $dbw->getMasterPos();
3770                 $lb->waitForAll( $pos );
3771         }
3772 }
3773
3774 /**
3775  * Used to be used for outputting text in the installer/updater
3776  * @deprecated since 1.18, warnings in 1.18, remove in 1.20
3777  */
3778 function wfOut( $s ) {
3779         wfDeprecated( __FUNCTION__, '1.18' );
3780         global $wgCommandLineMode;
3781         if ( $wgCommandLineMode ) {
3782                 echo $s;
3783         } else {
3784                 echo htmlspecialchars( $s );
3785         }
3786         flush();
3787 }
3788
3789 /**
3790  * Count down from $n to zero on the terminal, with a one-second pause
3791  * between showing each number. For use in command-line scripts.
3792  * @codeCoverageIgnore
3793  * @param $n int
3794  */
3795 function wfCountDown( $n ) {
3796         for ( $i = $n; $i >= 0; $i-- ) {
3797                 if ( $i != $n ) {
3798                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3799                 }
3800                 echo $i;
3801                 flush();
3802                 if ( $i ) {
3803                         sleep( 1 );
3804                 }
3805         }
3806         echo "\n";
3807 }
3808
3809 /**
3810  * Generate a random 32-character hexadecimal token.
3811  * @param $salt Mixed: some sort of salt, if necessary, to add to random
3812  *              characters before hashing.
3813  * @return string
3814  * @codeCoverageIgnore
3815  * @deprecated since 1.20; Please use MWCryptRand for security purposes and wfRandomString for pesudo-random strings
3816  * @warning This method is NOT secure. Additionally it has many callers that use it for pesudo-random purposes.
3817  */
3818 function wfGenerateToken( $salt = '' ) {
3819         wfDeprecated( __METHOD__, '1.20' );
3820         $salt = serialize( $salt );
3821         return md5( mt_rand( 0, 0x7fffffff ) . $salt );
3822 }
3823
3824 /**
3825  * Replace all invalid characters with -
3826  *
3827  * @param $name Mixed: filename to process
3828  * @return String
3829  */
3830 function wfStripIllegalFilenameChars( $name ) {
3831         global $wgIllegalFileChars;
3832         $name = wfBaseName( $name );
3833         $name = preg_replace(
3834                 "/[^" . Title::legalChars() . "]" .
3835                         ( $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '' ) .
3836                         "/",
3837                 '-',
3838                 $name
3839         );
3840         return $name;
3841 }
3842
3843 /**
3844  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit;
3845  *
3846  * @return Integer value memory was set to.
3847  */
3848 function wfMemoryLimit() {
3849         global $wgMemoryLimit;
3850         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3851         if( $memlimit != -1 ) {
3852                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3853                 if( $conflimit == -1 ) {
3854                         wfDebug( "Removing PHP's memory limit\n" );
3855                         wfSuppressWarnings();
3856                         ini_set( 'memory_limit', $conflimit );
3857                         wfRestoreWarnings();
3858                         return $conflimit;
3859                 } elseif ( $conflimit > $memlimit ) {
3860                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3861                         wfSuppressWarnings();
3862                         ini_set( 'memory_limit', $conflimit );
3863                         wfRestoreWarnings();
3864                         return $conflimit;
3865                 }
3866         }
3867         return $memlimit;
3868 }
3869
3870 /**
3871  * Converts shorthand byte notation to integer form
3872  *
3873  * @param $string String
3874  * @return Integer
3875  */
3876 function wfShorthandToInteger( $string = '' ) {
3877         $string = trim( $string );
3878         if( $string === '' ) {
3879                 return -1;
3880         }
3881         $last = $string[strlen( $string ) - 1];
3882         $val = intval( $string );
3883         switch( $last ) {
3884                 case 'g':
3885                 case 'G':
3886                         $val *= 1024;
3887                         // break intentionally missing
3888                 case 'm':
3889                 case 'M':
3890                         $val *= 1024;
3891                         // break intentionally missing
3892                 case 'k':
3893                 case 'K':
3894                         $val *= 1024;
3895         }
3896
3897         return $val;
3898 }
3899
3900 /**
3901  * Get the normalised IETF language tag
3902  * See unit test for examples.
3903  *
3904  * @param $code String: The language code.
3905  * @return String: The language code which complying with BCP 47 standards.
3906  */
3907 function wfBCP47( $code ) {
3908         $codeSegment = explode( '-', $code );
3909         $codeBCP = array();
3910         foreach ( $codeSegment as $segNo => $seg ) {
3911                 if ( count( $codeSegment ) > 0 ) {
3912                         // when previous segment is x, it is a private segment and should be lc
3913                         if( $segNo > 0 && strtolower( $codeSegment[( $segNo - 1 )] ) == 'x' ) {
3914                                 $codeBCP[$segNo] = strtolower( $seg );
3915                         // ISO 3166 country code
3916                         } elseif ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3917                                 $codeBCP[$segNo] = strtoupper( $seg );
3918                         // ISO 15924 script code
3919                         } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3920                                 $codeBCP[$segNo] = ucfirst( strtolower( $seg ) );
3921                         // Use lowercase for other cases
3922                         } else {
3923                                 $codeBCP[$segNo] = strtolower( $seg );
3924                         }
3925                 } else {
3926                 // Use lowercase for single segment
3927                         $codeBCP[$segNo] = strtolower( $seg );
3928                 }
3929         }
3930         $langCode = implode( '-', $codeBCP );
3931         return $langCode;
3932 }
3933
3934 /**
3935  * Get a cache object.
3936  *
3937  * @param $inputType integer Cache type, one the the CACHE_* constants.
3938  * @return BagOStuff
3939  */
3940 function wfGetCache( $inputType ) {
3941         return ObjectCache::getInstance( $inputType );
3942 }
3943
3944 /**
3945  * Get the main cache object
3946  *
3947  * @return BagOStuff
3948  */
3949 function wfGetMainCache() {
3950         global $wgMainCacheType;
3951         return ObjectCache::getInstance( $wgMainCacheType );
3952 }
3953
3954 /**
3955  * Get the cache object used by the message cache
3956  *
3957  * @return BagOStuff
3958  */
3959 function wfGetMessageCacheStorage() {
3960         global $wgMessageCacheType;
3961         return ObjectCache::getInstance( $wgMessageCacheType );
3962 }
3963
3964 /**
3965  * Get the cache object used by the parser cache
3966  *
3967  * @return BagOStuff
3968  */
3969 function wfGetParserCacheStorage() {
3970         global $wgParserCacheType;
3971         return ObjectCache::getInstance( $wgParserCacheType );
3972 }
3973
3974 /**
3975  * Get the cache object used by the language converter
3976  *
3977  * @return BagOStuff
3978  */
3979 function wfGetLangConverterCacheStorage() {
3980         global $wgLanguageConverterCacheType;
3981         return ObjectCache::getInstance( $wgLanguageConverterCacheType );
3982 }
3983
3984 /**
3985  * Call hook functions defined in $wgHooks
3986  *
3987  * @param $event String: event name
3988  * @param $args Array: parameters passed to hook functions
3989  * @return Boolean True if no handler aborted the hook
3990  */
3991 function wfRunHooks( $event, $args = array() ) {
3992         return Hooks::run( $event, $args );
3993 }
3994
3995 /**
3996  * Wrapper around php's unpack.
3997  *
3998  * @param $format String: The format string (See php's docs)
3999  * @param $data: A binary string of binary data
4000  * @param $length integer or false: The minimun length of $data. This is to
4001  *      prevent reading beyond the end of $data. false to disable the check.
4002  *
4003  * Also be careful when using this function to read unsigned 32 bit integer
4004  * because php might make it negative.
4005  *
4006  * @throws MWException if $data not long enough, or if unpack fails
4007  * @return array Associative array of the extracted data
4008  */
4009 function wfUnpack( $format, $data, $length=false ) {
4010         if ( $length !== false ) {
4011                 $realLen = strlen( $data );
4012                 if ( $realLen < $length ) {
4013                         throw new MWException( "Tried to use wfUnpack on a "
4014                                 . "string of length $realLen, but needed one "
4015                                 . "of at least length $length."
4016                         );
4017                 }
4018         }
4019
4020         wfSuppressWarnings();
4021         $result = unpack( $format, $data );
4022         wfRestoreWarnings();
4023
4024         if ( $result === false ) {
4025                 // If it cannot extract the packed data.
4026                 throw new MWException( "unpack could not unpack binary data" );
4027         }
4028         return $result;
4029 }
4030
4031 /**
4032  * Determine if an image exists on the 'bad image list'.
4033  *
4034  * The format of MediaWiki:Bad_image_list is as follows:
4035  *    * Only list items (lines starting with "*") are considered
4036  *    * The first link on a line must be a link to a bad image
4037  *    * Any subsequent links on the same line are considered to be exceptions,
4038  *      i.e. articles where the image may occur inline.
4039  *
4040  * @param $name string the image name to check
4041  * @param $contextTitle Title|bool the page on which the image occurs, if known
4042  * @param $blacklist string wikitext of a file blacklist
4043  * @return bool
4044  */
4045 function wfIsBadImage( $name, $contextTitle = false, $blacklist = null ) {
4046         static $badImageCache = null; // based on bad_image_list msg
4047         wfProfileIn( __METHOD__ );
4048
4049         # Handle redirects
4050         $redirectTitle = RepoGroup::singleton()->checkRedirect( Title::makeTitle( NS_FILE, $name ) );
4051         if( $redirectTitle ) {
4052                 $name = $redirectTitle->getDbKey();
4053         }
4054
4055         # Run the extension hook
4056         $bad = false;
4057         if( !wfRunHooks( 'BadImage', array( $name, &$bad ) ) ) {
4058                 wfProfileOut( __METHOD__ );
4059                 return $bad;
4060         }
4061
4062         $cacheable = ( $blacklist === null );
4063         if( $cacheable && $badImageCache !== null ) {
4064                 $badImages = $badImageCache;
4065         } else { // cache miss
4066                 if ( $blacklist === null ) {
4067                         $blacklist = wfMsgForContentNoTrans( 'bad_image_list' ); // site list
4068                 }
4069                 # Build the list now
4070                 $badImages = array();
4071                 $lines = explode( "\n", $blacklist );
4072                 foreach( $lines as $line ) {
4073                         # List items only
4074                         if ( substr( $line, 0, 1 ) !== '*' ) {
4075                                 continue;
4076                         }
4077
4078                         # Find all links
4079                         $m = array();
4080                         if ( !preg_match_all( '/\[\[:?(.*?)\]\]/', $line, $m ) ) {
4081                                 continue;
4082                         }
4083
4084                         $exceptions = array();
4085                         $imageDBkey = false;
4086                         foreach ( $m[1] as $i => $titleText ) {
4087                                 $title = Title::newFromText( $titleText );
4088                                 if ( !is_null( $title ) ) {
4089                                         if ( $i == 0 ) {
4090                                                 $imageDBkey = $title->getDBkey();
4091                                         } else {
4092                                                 $exceptions[$title->getPrefixedDBkey()] = true;
4093                                         }
4094                                 }
4095                         }
4096
4097                         if ( $imageDBkey !== false ) {
4098                                 $badImages[$imageDBkey] = $exceptions;
4099                         }
4100                 }
4101                 if ( $cacheable ) {
4102                         $badImageCache = $badImages;
4103                 }
4104         }
4105
4106         $contextKey = $contextTitle ? $contextTitle->getPrefixedDBkey() : false;
4107         $bad = isset( $badImages[$name] ) && !isset( $badImages[$name][$contextKey] );
4108         wfProfileOut( __METHOD__ );
4109         return $bad;
4110 }