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