includes/GlobalFunctions.php

   1 <?php
   2 /**
   3  * Global functions used everywhere
   4  * @file
   5  */
   6
   7 if ( !defined( 'MEDIAWIKI' ) ) {
   8         die( "This file is part of MediaWiki, it is not a valid entry point" );
   9 }
  10
  11 // Hide compatibility functions from Doxygen
  12 /// @cond
  13
  14 /**
  15  * Compatibility functions
  16  *
  17  * We support PHP 5.2.3 and up.
  18  * Re-implementations of newer functions or functions in non-standard
  19  * PHP extensions may be included here.
  20  */
  21
  22 if( !function_exists( 'iconv' ) ) {
  23         /**
  24          * @codeCoverageIgnore
  25          * @return string
  26          */
  27         function iconv( $from, $to, $string ) {
  28                 return Fallback::iconv( $from, $to, $string );
  29         }
  30 }
  31
  32 if ( !function_exists( 'mb_substr' ) ) {
  33         /**
  34          * @codeCoverageIgnore
  35          * @return string
  36          */
  37         function mb_substr( $str, $start, $count='end' ) {
  38                 return Fallback::mb_substr( $str, $start, $count );
  39         }
  40
  41         /**
  42          * @codeCoverageIgnore
  43          * @return int
  44          */
  45         function mb_substr_split_unicode( $str, $splitPos ) {
  46                 return Fallback::mb_substr_split_unicode( $str, $splitPos );
  47         }
  48 }
  49
  50 if ( !function_exists( 'mb_strlen' ) ) {
  51         /**
  52          * @codeCoverageIgnore
  53          * @return int
  54          */
  55         function mb_strlen( $str, $enc = '' ) {
  56                 return Fallback::mb_strlen( $str, $enc );
  57         }
  58 }
  59
  60 if( !function_exists( 'mb_strpos' ) ) {
  61         /**
  62          * @codeCoverageIgnore
  63          * @return int
  64          */
  65         function mb_strpos( $haystack, $needle, $offset = 0, $encoding = '' ) {
  66                 return Fallback::mb_strpos( $haystack, $needle, $offset, $encoding );
  67         }
  68
  69 }
  70
  71 if( !function_exists( 'mb_strrpos' ) ) {
  72         /**
  73          * @codeCoverageIgnore
  74          * @return int
  75          */
  76         function mb_strrpos( $haystack, $needle, $offset = 0, $encoding = '' ) {
  77                 return Fallback::mb_strrpos( $haystack, $needle, $offset, $encoding );
  78         }
  79 }
  80
  81
  82 // Support for Wietse Venema's taint feature
  83 if ( !function_exists( 'istainted' ) ) {
  84         /**
  85          * @codeCoverageIgnore
  86          * @return int
  87          */
  88         function istainted( $var ) {
  89                 return 0;
  90         }
  91         /** @codeCoverageIgnore */
  92         function taint( $var, $level = 0 ) {}
  93         /** @codeCoverageIgnore */
  94         function untaint( $var, $level = 0 ) {}
  95         define( 'TC_HTML', 1 );
  96         define( 'TC_SHELL', 1 );
  97         define( 'TC_MYSQL', 1 );
  98         define( 'TC_PCRE', 1 );
  99         define( 'TC_SELF', 1 );
 100 }
 101 /// @endcond
 102
 103 /**
 104  * Like array_diff( $a, $b ) except that it works with two-dimensional arrays.
 105  * @param $a array
 106  * @param $b array
 107  * @return array
 108  */
 109 function wfArrayDiff2( $a, $b ) {
 110         return array_udiff( $a, $b, 'wfArrayDiff2_cmp' );
 111 }
 112
 113 /**
 114  * @param $a
 115  * @param $b
 116  * @return int
 117  */
 118 function wfArrayDiff2_cmp( $a, $b ) {
 119         if ( !is_array( $a ) ) {
 120                 return strcmp( $a, $b );
 121         } elseif ( count( $a ) !== count( $b ) ) {
 122                 return count( $a ) < count( $b ) ? -1 : 1;
 123         } else {
 124                 reset( $a );
 125                 reset( $b );
 126                 while( ( list( , $valueA ) = each( $a ) ) && ( list( , $valueB ) = each( $b ) ) ) {
 127                         $cmp = strcmp( $valueA, $valueB );
 128                         if ( $cmp !== 0 ) {
 129                                 return $cmp;
 130                         }
 131                 }
 132                 return 0;
 133         }
 134 }
 135
 136 /**
 137  * Array lookup
 138  * Returns an array where the values in the first array are replaced by the
 139  * values in the second array with the corresponding keys
 140  *
 141  * @param $a Array
 142  * @param $b Array
 143  * @return array
 144  */
 145 function wfArrayLookup( $a, $b ) {
 146         return array_flip( array_intersect( array_flip( $a ), array_keys( $b ) ) );
 147 }
 148
 149 /**
 150  * Appends to second array if $value differs from that in $default
 151  *
 152  * @param $key String|Int
 153  * @param $value Mixed
 154  * @param $default Mixed
 155  * @param $changed Array to alter
 156  */
 157 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
 158         if ( is_null( $changed ) ) {
 159                 throw new MWException( 'GlobalFunctions::wfAppendToArrayIfNotDefault got null' );
 160         }
 161         if ( $default[$key] !== $value ) {
 162                 $changed[$key] = $value;
 163         }
 164 }
 165
 166 /**
 167  * Backwards array plus for people who haven't bothered to read the PHP manual
 168  * XXX: will not darn your socks for you.
 169  *
 170  * @param $array1 Array
 171  * @param [$array2, [...]] Arrays
 172  * @return Array
 173  */
 174 function wfArrayMerge( $array1/* ... */ ) {
 175         $args = func_get_args();
 176         $args = array_reverse( $args, true );
 177         $out = array();
 178         foreach ( $args as $arg ) {
 179                 $out += $arg;
 180         }
 181         return $out;
 182 }
 183
 184 /**
 185  * Merge arrays in the style of getUserPermissionsErrors, with duplicate removal
 186  * e.g.
 187  *      wfMergeErrorArrays(
 188  *              array( array( 'x' ) ),
 189  *              array( array( 'x', '2' ) ),
 190  *              array( array( 'x' ) ),
 191  *              array( array( 'y' ) )
 192  *      );
 193  * returns:
 194  *              array(
 195  *              array( 'x', '2' ),
 196  *              array( 'x' ),
 197  *              array( 'y' )
 198  *      )
 199  * @param varargs
 200  * @return Array
 201  */
 202 function wfMergeErrorArrays( /*...*/ ) {
 203         $args = func_get_args();
 204         $out = array();
 205         foreach ( $args as $errors ) {
 206                 foreach ( $errors as $params ) {
 207                         # @todo FIXME: Sometimes get nested arrays for $params,
 208                         # which leads to E_NOTICEs
 209                         $spec = implode( "\t", $params );
 210                         $out[$spec] = $params;
 211                 }
 212         }
 213         return array_values( $out );
 214 }
 215
 216 /**
 217  * Insert array into another array after the specified *KEY*
 218  *
 219  * @param $array Array: The array.
 220  * @param $insert Array: The array to insert.
 221  * @param $after Mixed: The key to insert after
 222  * @return Array
 223  */
 224 function wfArrayInsertAfter( array $array, array $insert, $after ) {
 225         // Find the offset of the element to insert after.
 226         $keys = array_keys( $array );
 227         $offsetByKey = array_flip( $keys );
 228
 229         $offset = $offsetByKey[$after];
 230
 231         // Insert at the specified offset
 232         $before = array_slice( $array, 0, $offset + 1, true );
 233         $after = array_slice( $array, $offset + 1, count( $array ) - $offset, true );
 234
 235         $output = $before + $insert + $after;
 236
 237         return $output;
 238 }
 239
 240 /**
 241  * Recursively converts the parameter (an object) to an array with the same data
 242  *
 243  * @param $objOrArray Object|Array
 244  * @param $recursive Bool
 245  * @return Array
 246  */
 247 function wfObjectToArray( $objOrArray, $recursive = true ) {
 248         $array = array();
 249         if( is_object( $objOrArray ) ) {
 250                 $objOrArray = get_object_vars( $objOrArray );
 251         }
 252         foreach ( $objOrArray as $key => $value ) {
 253                 if ( $recursive && ( is_object( $value ) || is_array( $value ) ) ) {
 254                         $value = wfObjectToArray( $value );
 255                 }
 256
 257                 $array[$key] = $value;
 258         }
 259
 260         return $array;
 261 }
 262
 263 /**
 264  * Wrapper around array_map() which also taints variables
 265  *
 266  * @param  $function Callback
 267  * @param  $input Array
 268  * @return Array
 269  */
 270 function wfArrayMap( $function, $input ) {
 271         $ret = array_map( $function, $input );
 272         foreach ( $ret as $key => $value ) {
 273                 $taint = istainted( $input[$key] );
 274                 if ( $taint ) {
 275                         taint( $ret[$key], $taint );
 276                 }
 277         }
 278         return $ret;
 279 }
 280
 281 /**
 282  * Get a random decimal value between 0 and 1, in a way
 283  * not likely to give duplicate values for any realistic
 284  * number of articles.
 285  *
 286  * @return string
 287  */
 288 function wfRandom() {
 289         # The maximum random value is "only" 2^31-1, so get two random
 290         # values to reduce the chance of dupes
 291         $max = mt_getrandmax() + 1;
 292         $rand = number_format( ( mt_rand() * $max + mt_rand() )
 293                 / $max / $max, 12, '.', '' );
 294         return $rand;
 295 }
 296
 297 /**
 298  * Get a random string containing a number of pesudo-random hex
 299  * characters.
 300  * @note This is not secure, if you are trying to generate some sort
 301  *       of token please use MWCryptRand instead.
 302  *
 303  * @param $length int The length of the string to generate
 304  * @return String
 305  * @since 1.20
 306  */
 307 function wfRandomString( $length = 32 ) {
 308         $str = '';
 309         while ( strlen( $str ) < $length ) {
 310                 $str .= dechex( mt_rand() );
 311         }
 312         return substr( $str, 0, $length );
 313 }
 314
 315 /**
 316  * We want some things to be included as literal characters in our title URLs
 317  * for prettiness, which urlencode encodes by default.  According to RFC 1738,
 318  * all of the following should be safe:
 319  *
 320  * ;:@&=$-_.+!*'(),
 321  *
 322  * But + is not safe because it's used to indicate a space; &= are only safe in
 323  * paths and not in queries (and we don't distinguish here); ' seems kind of
 324  * scary; and urlencode() doesn't touch -_. to begin with.  Plus, although /
 325  * is reserved, we don't care.  So the list we unescape is:
 326  *
 327  * ;:@$!*(),/
 328  *
 329  * However, IIS7 redirects fail when the url contains a colon (Bug 22709),
 330  * so no fancy : for IIS7.
 331  *
 332  * %2F in the page titles seems to fatally break for some reason.
 333  *
 334  * @param $s String:
 335  * @return string
 336 */
 337 function wfUrlencode( $s ) {
 338         static $needle;
 339         if ( is_null( $s ) ) {
 340                 $needle = null;
 341                 return '';
 342         }
 343
 344         if ( is_null( $needle ) ) {
 345                 $needle = array( '%3B', '%40', '%24', '%21', '%2A', '%28', '%29', '%2C', '%2F' );
 346                 if ( !isset( $_SERVER['SERVER_SOFTWARE'] ) || ( strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/7' ) === false ) ) {
 347                         $needle[] = '%3A';
 348                 }
 349         }
 350
 351         $s = urlencode( $s );
 352         $s = str_ireplace(
 353                 $needle,
 354                 array( ';', '@', '$', '!', '*', '(', ')', ',', '/', ':' ),
 355                 $s
 356         );
 357
 358         return $s;
 359 }
 360
 361 /**
 362  * This function takes two arrays as input, and returns a CGI-style string, e.g.
 363  * "days=7&limit=100". Options in the first array override options in the second.
 364  * Options set to null or false will not be output.
 365  *
 366  * @param $array1 Array ( String|Array )
 367  * @param $array2 Array ( String|Array )
 368  * @param $prefix String
 369  * @return String
 370  */
 371 function wfArrayToCGI( $array1, $array2 = null, $prefix = '' ) {
 372         if ( !is_null( $array2 ) ) {
 373                 $array1 = $array1 + $array2;
 374         }
 375
 376         $cgi = '';
 377         foreach ( $array1 as $key => $value ) {
 378                 if ( !is_null($value) && $value !== false ) {
 379                         if ( $cgi != '' ) {
 380                                 $cgi .= '&';
 381                         }
 382                         if ( $prefix !== '' ) {
 383                                 $key = $prefix . "[$key]";
 384                         }
 385                         if ( is_array( $value ) ) {
 386                                 $firstTime = true;
 387                                 foreach ( $value as $k => $v ) {
 388                                         $cgi .= $firstTime ? '' : '&';
 389                                         if ( is_array( $v ) ) {
 390                                                 $cgi .= wfArrayToCGI( $v, null, $key . "[$k]" );
 391                                         } else {
 392                                                 $cgi .= urlencode( $key . "[$k]" ) . '=' . urlencode( $v );
 393                                         }
 394                                         $firstTime = false;
 395                                 }
 396                         } else {
 397                                 if ( is_object( $value ) ) {
 398                                         $value = $value->__toString();
 399                                 }
 400                                 $cgi .= urlencode( $key ) . '=' . urlencode( $value );
 401                         }
 402                 }
 403         }
 404         return $cgi;
 405 }
 406
 407 /**
 408  * This is the logical opposite of wfArrayToCGI(): it accepts a query string as
 409  * its argument and returns the same string in array form.  This allows compa-
 410  * tibility with legacy functions that accept raw query strings instead of nice
 411  * arrays.  Of course, keys and values are urldecode()d.
 412  *
 413  * @param $query String: query string
 414  * @return array Array version of input
 415  */
 416 function wfCgiToArray( $query ) {
 417         if ( isset( $query[0] ) && $query[0] == '?' ) {
 418                 $query = substr( $query, 1 );
 419         }
 420         $bits = explode( '&', $query );
 421         $ret = array();
 422         foreach ( $bits as $bit ) {
 423                 if ( $bit === '' ) {
 424                         continue;
 425                 }
 426                 if ( strpos( $bit, '=' ) === false ) {
 427                         // Pieces like &qwerty become 'qwerty' => '' (at least this is what php does)
 428                         $key = $bit;
 429                         $value = '';
 430                 } else {
 431                         list( $key, $value ) = explode( '=', $bit );
 432                 }
 433                 $key = urldecode( $key );
 434                 $value = urldecode( $value );
 435                 if ( strpos( $key, '[' ) !== false ) {
 436                         $keys = array_reverse( explode( '[', $key ) );
 437                         $key = array_pop( $keys );
 438                         $temp = $value;
 439                         foreach ( $keys as $k ) {
 440                                 $k = substr( $k, 0, -1 );
 441                                 $temp = array( $k => $temp );
 442                         }
 443                         if ( isset( $ret[$key] ) ) {
 444                                 $ret[$key] = array_merge( $ret[$key], $temp );
 445                         } else {
 446                                 $ret[$key] = $temp;
 447                         }
 448                 } else {
 449                         $ret[$key] = $value;
 450                 }
 451         }
 452         return $ret;
 453 }
 454
 455 /**
 456  * Append a query string to an existing URL, which may or may not already
 457  * have query string parameters already. If so, they will be combined.
 458  *
 459  * @param $url String
 460  * @param $query Mixed: string or associative array
 461  * @return string
 462  */
 463 function wfAppendQuery( $url, $query ) {
 464         if ( is_array( $query ) ) {
 465                 $query = wfArrayToCGI( $query );
 466         }
 467         if( $query != '' ) {
 468                 if( false === strpos( $url, '?' ) ) {
 469                         $url .= '?';
 470                 } else {
 471                         $url .= '&';
 472                 }
 473                 $url .= $query;
 474         }
 475         return $url;
 476 }
 477
 478 /**
 479  * Expand a potentially local URL to a fully-qualified URL.  Assumes $wgServer
 480  * is correct.
 481  *
 482  * The meaning of the PROTO_* constants is as follows:
 483  * PROTO_HTTP: Output a URL starting with http://
 484  * PROTO_HTTPS: Output a URL starting with https://
 485  * PROTO_RELATIVE: Output a URL starting with // (protocol-relative URL)
 486  * PROTO_CURRENT: Output a URL starting with either http:// or https:// , depending on which protocol was used for the current incoming request
 487  * PROTO_CANONICAL: For URLs without a domain, like /w/index.php , use $wgCanonicalServer. For protocol-relative URLs, use the protocol of $wgCanonicalServer
 488  * PROTO_INTERNAL: Like PROTO_CANONICAL, but uses $wgInternalServer instead of $wgCanonicalServer
 489  *
 490  * @todo this won't work with current-path-relative URLs
 491  * like "subdir/foo.html", etc.
 492  *
 493  * @param $url String: either fully-qualified or a local path + query
 494  * @param $defaultProto Mixed: one of the PROTO_* constants. Determines the
 495  *                             protocol to use if $url or $wgServer is
 496  *                             protocol-relative
 497  * @return string Fully-qualified URL, current-path-relative URL or false if
 498  *                no valid URL can be constructed
 499  */
 500 function wfExpandUrl( $url, $defaultProto = PROTO_CURRENT ) {
 501         global $wgServer, $wgCanonicalServer, $wgInternalServer;
 502         $serverUrl = $wgServer;
 503         if ( $defaultProto === PROTO_CANONICAL ) {
 504                 $serverUrl = $wgCanonicalServer;
 505         }
 506         // Make $wgInternalServer fall back to $wgServer if not set
 507         if ( $defaultProto === PROTO_INTERNAL && $wgInternalServer !== false ) {
 508                 $serverUrl = $wgInternalServer;
 509         }
 510         if ( $defaultProto === PROTO_CURRENT ) {
 511                 $defaultProto = WebRequest::detectProtocol() . '://';
 512         }
 513
 514         // Analyze $serverUrl to obtain its protocol
 515         $bits = wfParseUrl( $serverUrl );
 516         $serverHasProto = $bits && $bits['scheme'] != '';
 517
 518         if ( $defaultProto === PROTO_CANONICAL || $defaultProto === PROTO_INTERNAL ) {
 519                 if ( $serverHasProto ) {
 520                         $defaultProto = $bits['scheme'] . '://';
 521                 } else {
 522                         // $wgCanonicalServer or $wgInternalServer doesn't have a protocol. This really isn't supposed to happen
 523                         // Fall back to HTTP in this ridiculous case
 524                         $defaultProto = PROTO_HTTP;
 525                 }
 526         }
 527
 528         $defaultProtoWithoutSlashes = substr( $defaultProto, 0, -2 );
 529
 530         if ( substr( $url, 0, 2 ) == '//' ) {
 531                 $url = $defaultProtoWithoutSlashes . $url;
 532         } elseif ( substr( $url, 0, 1 ) == '/' ) {
 533                 // If $serverUrl is protocol-relative, prepend $defaultProtoWithoutSlashes, otherwise leave it alone
 534                 $url = ( $serverHasProto ? '' : $defaultProtoWithoutSlashes ) . $serverUrl . $url;
 535         }
 536
 537         $bits = wfParseUrl( $url );
 538         if ( $bits && isset( $bits['path'] ) ) {
 539                 $bits['path'] = wfRemoveDotSegments( $bits['path'] );
 540                 return wfAssembleUrl( $bits );
 541         } elseif ( $bits ) {
 542                 # No path to expand
 543                 return $url;
 544         } elseif ( substr( $url, 0, 1 ) != '/' ) {
 545                 # URL is a relative path
 546                 return wfRemoveDotSegments( $url );
 547         }
 548
 549         # Expanded URL is not valid.
 550         return false;
 551 }
 552
 553 /**
 554  * This function will reassemble a URL parsed with wfParseURL.  This is useful
 555  * if you need to edit part of a URL and put it back together.
 556  *
 557  * This is the basic structure used (brackets contain keys for $urlParts):
 558  * [scheme][delimiter][user]:[pass]@[host]:[port][path]?[query]#[fragment]
 559  *
 560  * @todo Need to integrate this into wfExpandUrl (bug 32168)
 561  *
 562  * @param $urlParts Array URL parts, as output from wfParseUrl
 563  * @return string URL assembled from its component parts
 564  */
 565 function wfAssembleUrl( $urlParts ) {
 566         $result = '';
 567
 568         if ( isset( $urlParts['delimiter'] ) ) {
 569                 if ( isset( $urlParts['scheme'] ) ) {
 570                         $result .= $urlParts['scheme'];
 571                 }
 572
 573                 $result .= $urlParts['delimiter'];
 574         }
 575
 576         if ( isset( $urlParts['host'] ) ) {
 577                 if ( isset( $urlParts['user'] ) ) {
 578                         $result .= $urlParts['user'];
 579                         if ( isset( $urlParts['pass'] ) ) {
 580                                 $result .= ':' . $urlParts['pass'];
 581                         }
 582                         $result .= '@';
 583                 }
 584
 585                 $result .= $urlParts['host'];
 586
 587                 if ( isset( $urlParts['port'] ) ) {
 588                         $result .= ':' . $urlParts['port'];
 589                 }
 590         }
 591
 592         if ( isset( $urlParts['path'] ) ) {
 593                 $result .= $urlParts['path'];
 594         }
 595
 596         if ( isset( $urlParts['query'] ) ) {
 597                 $result .= '?' . $urlParts['query'];
 598         }
 599
 600         if ( isset( $urlParts['fragment'] ) ) {
 601                 $result .= '#' . $urlParts['fragment'];
 602         }
 603
 604         return $result;
 605 }
 606
 607 /**
 608  * Remove all dot-segments in the provided URL path.  For example,
 609  * '/a/./b/../c/' becomes '/a/c/'.  For details on the algorithm, please see
 610  * RFC3986 section 5.2.4.
 611  *
 612  * @todo Need to integrate this into wfExpandUrl (bug 32168)
 613  *
 614  * @param $urlPath String URL path, potentially containing dot-segments
 615  * @return string URL path with all dot-segments removed
 616  */
 617 function wfRemoveDotSegments( $urlPath ) {
 618         $output = '';
 619         $inputOffset = 0;
 620         $inputLength = strlen( $urlPath );
 621
 622         while ( $inputOffset < $inputLength ) {
 623                 $prefixLengthOne = substr( $urlPath, $inputOffset, 1 );
 624                 $prefixLengthTwo = substr( $urlPath, $inputOffset, 2 );
 625                 $prefixLengthThree = substr( $urlPath, $inputOffset, 3 );
 626                 $prefixLengthFour = substr( $urlPath, $inputOffset, 4 );
 627                 $trimOutput = false;
 628
 629                 if ( $prefixLengthTwo == './' ) {
 630                         # Step A, remove leading "./"
 631                         $inputOffset += 2;
 632                 } elseif ( $prefixLengthThree == '../' ) {
 633                         # Step A, remove leading "../"
 634                         $inputOffset += 3;
 635                 } elseif ( ( $prefixLengthTwo == '/.' ) && ( $inputOffset + 2 == $inputLength ) ) {
 636                         # Step B, replace leading "/.$" with "/"
 637                         $inputOffset += 1;
 638                         $urlPath[$inputOffset] = '/';
 639                 } elseif ( $prefixLengthThree == '/./' ) {
 640                         # Step B, replace leading "/./" with "/"
 641                         $inputOffset += 2;
 642                 } elseif ( $prefixLengthThree == '/..' && ( $inputOffset + 3 == $inputLength ) ) {
 643                         # Step C, replace leading "/..$" with "/" and
 644                         # remove last path component in output
 645                         $inputOffset += 2;
 646                         $urlPath[$inputOffset] = '/';
 647                         $trimOutput = true;
 648                 } elseif ( $prefixLengthFour == '/../' ) {
 649                         # Step C, replace leading "/../" with "/" and
 650                         # remove last path component in output
 651                         $inputOffset += 3;
 652                         $trimOutput = true;
 653                 } elseif ( ( $prefixLengthOne == '.' ) && ( $inputOffset + 1 == $inputLength ) ) {
 654                         # Step D, remove "^.$"
 655                         $inputOffset += 1;
 656                 } elseif ( ( $prefixLengthTwo == '..' ) && ( $inputOffset + 2 == $inputLength ) ) {
 657                         # Step D, remove "^..$"
 658                         $inputOffset += 2;
 659                 } else {
 660                         # Step E, move leading path segment to output
 661                         if ( $prefixLengthOne == '/' ) {
 662                                 $slashPos = strpos( $urlPath, '/', $inputOffset + 1 );
 663                         } else {
 664                                 $slashPos = strpos( $urlPath, '/', $inputOffset );
 665                         }
 666                         if ( $slashPos === false ) {
 667                                 $output .= substr( $urlPath, $inputOffset );
 668                                 $inputOffset = $inputLength;
 669                         } else {
 670                                 $output .= substr( $urlPath, $inputOffset, $slashPos - $inputOffset );
 671                                 $inputOffset += $slashPos - $inputOffset;
 672                         }
 673                 }
 674
 675                 if ( $trimOutput ) {
 676                         $slashPos = strrpos( $output, '/' );
 677                         if ( $slashPos === false ) {
 678                                 $output = '';
 679                         } else {
 680                                 $output = substr( $output, 0, $slashPos );
 681                         }
 682                 }
 683         }
 684
 685         return $output;
 686 }
 687
 688 /**
 689  * Returns a regular expression of url protocols
 690  *
 691  * @param $includeProtocolRelative bool If false, remove '//' from the returned protocol list.
 692  *        DO NOT USE this directly, use wfUrlProtocolsWithoutProtRel() instead
 693  * @return String
 694  */
 695 function wfUrlProtocols( $includeProtocolRelative = true ) {
 696         global $wgUrlProtocols;
 697
 698         // Cache return values separately based on $includeProtocolRelative
 699         static $withProtRel = null, $withoutProtRel = null;
 700         $cachedValue = $includeProtocolRelative ? $withProtRel : $withoutProtRel;
 701         if ( !is_null( $cachedValue ) ) {
 702                 return $cachedValue;
 703         }
 704
 705         // Support old-style $wgUrlProtocols strings, for backwards compatibility
 706         // with LocalSettings files from 1.5
 707         if ( is_array( $wgUrlProtocols ) ) {
 708                 $protocols = array();
 709                 foreach ( $wgUrlProtocols as $protocol ) {
 710                         // Filter out '//' if !$includeProtocolRelative
 711                         if ( $includeProtocolRelative || $protocol !== '//' ) {
 712                                 $protocols[] = preg_quote( $protocol, '/' );
 713                         }
 714                 }
 715
 716                 $retval = implode( '|', $protocols );
 717         } else {
 718                 // Ignore $includeProtocolRelative in this case
 719                 // This case exists for pre-1.6 compatibility, and we can safely assume
 720                 // that '//' won't appear in a pre-1.6 config because protocol-relative
 721                 // URLs weren't supported until 1.18
 722                 $retval = $wgUrlProtocols;
 723         }
 724
 725         // Cache return value
 726         if ( $includeProtocolRelative ) {
 727                 $withProtRel = $retval;
 728         } else {
 729                 $withoutProtRel = $retval;
 730         }
 731         return $retval;
 732 }
 733
 734 /**
 735  * Like wfUrlProtocols(), but excludes '//' from the protocol list. Use this if
 736  * you need a regex that matches all URL protocols but does not match protocol-
 737  * relative URLs
 738  * @return String
 739  */
 740 function wfUrlProtocolsWithoutProtRel() {
 741         return wfUrlProtocols( false );
 742 }
 743
 744 /**
 745  * parse_url() work-alike, but non-broken.  Differences:
 746  *
 747  * 1) Does not raise warnings on bad URLs (just returns false)
 748  * 2) Handles protocols that don't use :// (e.g., mailto: and news: , as well as protocol-relative URLs) correctly
 749  * 3) Adds a "delimiter" element to the array, either '://', ':' or '//' (see (2))
 750  *
 751  * @param $url String: a URL to parse
 752  * @return Array: bits of the URL in an associative array, per PHP docs
 753  */
 754 function wfParseUrl( $url ) {
 755         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
 756
 757         // Protocol-relative URLs are handled really badly by parse_url(). It's so bad that the easiest
 758         // way to handle them is to just prepend 'http:' and strip the protocol out later
 759         $wasRelative = substr( $url, 0, 2 ) == '//';
 760         if ( $wasRelative ) {
 761                 $url = "http:$url";
 762         }
 763         wfSuppressWarnings();
 764         $bits = parse_url( $url );
 765         wfRestoreWarnings();
 766         // parse_url() returns an array without scheme for some invalid URLs, e.g.
 767         // parse_url("%0Ahttp://example.com") == array( 'host' => '%0Ahttp', 'path' => 'example.com' )
 768         if ( !$bits || !isset( $bits['scheme'] ) ) {
 769                 return false;
 770         }
 771
 772         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
 773         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
 774                 $bits['delimiter'] = '://';
 775         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
 776                 $bits['delimiter'] = ':';
 777                 // parse_url detects for news: and mailto: the host part of an url as path
 778                 // We have to correct this wrong detection
 779                 if ( isset( $bits['path'] ) ) {
 780                         $bits['host'] = $bits['path'];
 781                         $bits['path'] = '';
 782                 }
 783         } else {
 784                 return false;
 785         }
 786
 787         /* Provide an empty host for eg. file:/// urls (see bug 28627) */
 788         if ( !isset( $bits['host'] ) ) {
 789                 $bits['host'] = '';
 790
 791                 /* parse_url loses the third / for file:///c:/ urls (but not on variants) */
 792                 if ( substr( $bits['path'], 0, 1 ) !== '/' ) {
 793                         $bits['path'] = '/' . $bits['path'];
 794                 }
 795         }
 796
 797         // If the URL was protocol-relative, fix scheme and delimiter
 798         if ( $wasRelative ) {
 799                 $bits['scheme'] = '';
 800                 $bits['delimiter'] = '//';
 801         }
 802         return $bits;
 803 }
 804
 805 /**
 806  * Take a URL, make sure it's expanded to fully qualified, and replace any
 807  * encoded non-ASCII Unicode characters with their UTF-8 original forms
 808  * for more compact display and legibility for local audiences.
 809  *
 810  * @todo handle punycode domains too
 811  *
 812  * @param $url string
 813  * @return string
 814  */
 815 function wfExpandIRI( $url ) {
 816         return preg_replace_callback( '/((?:%[89A-F][0-9A-F])+)/i', 'wfExpandIRI_callback', wfExpandUrl( $url ) );
 817 }
 818
 819 /**
 820  * Private callback for wfExpandIRI
 821  * @param array $matches
 822  * @return string
 823  */
 824 function wfExpandIRI_callback( $matches ) {
 825         return urldecode( $matches[1] );
 826 }
 827
 828
 829
 830 /**
 831  * Make URL indexes, appropriate for the el_index field of externallinks.
 832  *
 833  * @param $url String
 834  * @return array
 835  */
 836 function wfMakeUrlIndexes( $url ) {
 837         $bits = wfParseUrl( $url );
 838
 839         // Reverse the labels in the hostname, convert to lower case
 840         // For emails reverse domainpart only
 841         if ( $bits['scheme'] == 'mailto' ) {
 842                 $mailparts = explode( '@', $bits['host'], 2 );
 843                 if ( count( $mailparts ) === 2 ) {
 844                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
 845                 } else {
 846                         // No domain specified, don't mangle it
 847                         $domainpart = '';
 848                 }
 849                 $reversedHost = $domainpart . '@' . $mailparts[0];
 850         } else {
 851                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
 852         }
 853         // Add an extra dot to the end
 854         // Why? Is it in wrong place in mailto links?
 855         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
 856                 $reversedHost .= '.';
 857         }
 858         // Reconstruct the pseudo-URL
 859         $prot = $bits['scheme'];
 860         $index = $prot . $bits['delimiter'] . $reversedHost;
 861         // Leave out user and password. Add the port, path, query and fragment
 862         if ( isset( $bits['port'] ) ) {
 863                 $index .= ':' . $bits['port'];
 864         }
 865         if ( isset( $bits['path'] ) ) {
 866                 $index .= $bits['path'];
 867         } else {
 868                 $index .= '/';
 869         }
 870         if ( isset( $bits['query'] ) ) {
 871                 $index .= '?' . $bits['query'];
 872         }
 873         if ( isset( $bits['fragment'] ) ) {
 874                 $index .= '#' . $bits['fragment'];
 875         }
 876
 877         if ( $prot == '' ) {
 878                 return array( "http:$index", "https:$index" );
 879         } else {
 880                 return array( $index );
 881         }
 882 }
 883
 884 /**
 885  * Check whether a given URL has a domain that occurs in a given set of domains
 886  * @param $url string URL
 887  * @param $domains array Array of domains (strings)
 888  * @return bool True if the host part of $url ends in one of the strings in $domains
 889  */
 890 function wfMatchesDomainList( $url, $domains ) {
 891         $bits = wfParseUrl( $url );
 892         if ( is_array( $bits ) && isset( $bits['host'] ) ) {
 893                 foreach ( (array)$domains as $domain ) {
 894                         // FIXME: This gives false positives. http://nds-nl.wikipedia.org will match nl.wikipedia.org
 895                         // We should use something that interprets dots instead
 896                         if ( substr( $bits['host'], -strlen( $domain ) ) === $domain ) {
 897                                 return true;
 898                         }
 899                 }
 900         }
 901         return false;
 902 }
 903
 904 /**
 905  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
 906  * In normal operation this is a NOP.
 907  *
 908  * Controlling globals:
 909  * $wgDebugLogFile - points to the log file
 910  * $wgProfileOnly - if set, normal debug messages will not be recorded.
 911  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
 912  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
 913  *
 914  * @param $text String
 915  * @param $logonly Bool: set true to avoid appearing in HTML when $wgDebugComments is set
 916  */
 917 function wfDebug( $text, $logonly = false ) {
 918         global $wgOut, $wgDebugLogFile, $wgDebugComments, $wgProfileOnly, $wgDebugRawPage;
 919         global $wgDebugLogPrefix, $wgShowDebug;
 920
 921         static $cache = array(); // Cache of unoutputted messages
 922
 923         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
 924                 return;
 925         }
 926
 927         $timer = wfDebugTimer();
 928         if ( $timer !== '' ) {
 929                 $text = preg_replace( '/[^\n]/', $timer . '\0', $text, 1 );
 930         }
 931
 932         if ( ( $wgDebugComments || $wgShowDebug ) && !$logonly ) {
 933                 $cache[] = $text;
 934
 935                 if ( isset( $wgOut ) && is_object( $wgOut ) ) {
 936                         // add the message and any cached messages to the output
 937                         array_map( array( $wgOut, 'debug' ), $cache );
 938                         $cache = array();
 939                 }
 940         }
 941         if ( wfRunHooks( 'Debug', array( $text, null /* no log group */ ) ) ) {
 942                 if ( $wgDebugLogFile != '' && !$wgProfileOnly ) {
 943                         # Strip unprintables; they can switch terminal modes when binary data
 944                         # gets dumped, which is pretty annoying.
 945                         $text = preg_replace( '![\x00-\x08\x0b\x0c\x0e-\x1f]!', ' ', $text );
 946                         $text = $wgDebugLogPrefix . $text;
 947                         wfErrorLog( $text, $wgDebugLogFile );
 948                 }
 949         }
 950
 951         MWDebug::debugMsg( $text );
 952 }
 953
 954 /**
 955  * Returns true if debug logging should be suppressed if $wgDebugRawPage = false
 956  * @return bool
 957  */
 958 function wfIsDebugRawPage() {
 959         static $cache;
 960         if ( $cache !== null ) {
 961                 return $cache;
 962         }
 963         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
 964         if ( ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' )
 965                 || (
 966                         isset( $_SERVER['SCRIPT_NAME'] )
 967                         && substr( $_SERVER['SCRIPT_NAME'], -8 ) == 'load.php'
 968                 ) )
 969         {
 970                 $cache = true;
 971         } else {
 972                 $cache = false;
 973         }
 974         return $cache;
 975 }
 976
 977 /**
 978  * Get microsecond timestamps for debug logs
 979  *
 980  * @return string
 981  */
 982 function wfDebugTimer() {
 983         global $wgDebugTimestamps, $wgRequestTime;
 984
 985         if ( !$wgDebugTimestamps ) {
 986                 return '';
 987         }
 988
 989         $prefix = sprintf( "%6.4f", microtime( true ) - $wgRequestTime );
 990         $mem = sprintf( "%5.1fM", ( memory_get_usage( true ) / ( 1024 * 1024 ) ) );
 991         return "$prefix $mem  ";
 992 }
 993
 994 /**
 995  * Send a line giving PHP memory usage.
 996  *
 997  * @param $exact Bool: print exact values instead of kilobytes (default: false)
 998  */
 999 function wfDebugMem( $exact = false ) {
1000         $mem = memory_get_usage();
1001         if( !$exact ) {
1002                 $mem = floor( $mem / 1024 ) . ' kilobytes';
1003         } else {
1004                 $mem .= ' bytes';
1005         }
1006         wfDebug( "Memory usage: $mem\n" );
1007 }
1008
1009 /**
1010  * Send a line to a supplementary debug log file, if configured, or main debug log if not.
1011  * $wgDebugLogGroups[$logGroup] should be set to a filename to send to a separate log.
1012  *
1013  * @param $logGroup String
1014  * @param $text String
1015  * @param $public Bool: whether to log the event in the public log if no private
1016  *                     log file is specified, (default true)
1017  */
1018 function wfDebugLog( $logGroup, $text, $public = true ) {
1019         global $wgDebugLogGroups;
1020         $text = trim( $text ) . "\n";
1021         if( isset( $wgDebugLogGroups[$logGroup] ) ) {
1022                 $time = wfTimestamp( TS_DB );
1023                 $wiki = wfWikiID();
1024                 $host = wfHostname();
1025                 if ( wfRunHooks( 'Debug', array( $text, $logGroup ) ) ) {
1026                         wfErrorLog( "$time $host $wiki: $text", $wgDebugLogGroups[$logGroup] );
1027                 }
1028         } elseif ( $public === true ) {
1029                 wfDebug( $text, true );
1030         }
1031 }
1032
1033 /**
1034  * Log for database errors
1035  *
1036  * @param $text String: database error message.
1037  */
1038 function wfLogDBError( $text ) {
1039         global $wgDBerrorLog;
1040         if ( $wgDBerrorLog ) {
1041                 $host = wfHostname();
1042                 $wiki = wfWikiID();
1043                 $text = date( 'D M j G:i:s T Y' ) . "\t$host\t$wiki\t$text";
1044                 wfErrorLog( $text, $wgDBerrorLog );
1045         }
1046 }
1047
1048 /**
1049  * Throws a warning that $function is deprecated
1050  *
1051  * @param $function String
1052  * @param $version String|bool: Version of MediaWiki that the function was deprecated in (Added in 1.19).
1053  * @param $component String|bool: Added in 1.19.
1054  * @param $callerOffset integer: How far up the callstack is the original
1055  *    caller. 2 = function that called the function that called
1056  *    wfDeprecated (Added in 1.20)
1057  *
1058  * @return null
1059  */
1060 function wfDeprecated( $function, $version = false, $component = false, $callerOffset = 2 ) {
1061         static $functionsWarned = array();
1062
1063         MWDebug::deprecated( $function, $version, $component );
1064
1065         if ( !isset( $functionsWarned[$function] ) ) {
1066                 $functionsWarned[$function] = true;
1067
1068                 if ( $version ) {
1069                         global $wgDeprecationReleaseLimit;
1070
1071                         if ( $wgDeprecationReleaseLimit && $component === false ) {
1072                                 # Strip -* off the end of $version so that branches can use the
1073                                 # format #.##-branchname to avoid issues if the branch is merged into
1074                                 # a version of MediaWiki later than what it was branched from
1075                                 $comparableVersion = preg_replace( '/-.*$/', '', $version );
1076
1077                                 # If the comparableVersion is larger than our release limit then
1078                                 # skip the warning message for the deprecation
1079                                 if ( version_compare( $wgDeprecationReleaseLimit, $comparableVersion, '<' ) ) {
1080                                         return;
1081                                 }
1082                         }
1083
1084                         $component = $component === false ? 'MediaWiki' : $component;
1085                         wfWarn( "Use of $function was deprecated in $component $version.", $callerOffset );
1086                 } else {
1087                         wfWarn( "Use of $function is deprecated.", $callerOffset );
1088                 }
1089         }
1090 }
1091
1092 /**
1093  * Send a warning either to the debug log or in a PHP error depending on
1094  * $wgDevelopmentWarnings
1095  *
1096  * @param $msg String: message to send
1097  * @param $callerOffset Integer: number of items to go back in the backtrace to
1098  *        find the correct caller (1 = function calling wfWarn, ...)
1099  * @param $level Integer: PHP error level; only used when $wgDevelopmentWarnings
1100  *        is true
1101  */
1102 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
1103         global $wgDevelopmentWarnings;
1104
1105         MWDebug::warning( $msg, $callerOffset + 2 );
1106
1107         $callers = wfDebugBacktrace();
1108         if ( isset( $callers[$callerOffset + 1] ) ) {
1109                 $callerfunc = $callers[$callerOffset + 1];
1110                 $callerfile = $callers[$callerOffset];
1111                 if ( isset( $callerfile['file'] ) && isset( $callerfile['line'] ) ) {
1112                         $file = $callerfile['file'] . ' at line ' . $callerfile['line'];
1113                 } else {
1114                         $file = '(internal function)';
1115                 }
1116                 $func = '';
1117                 if ( isset( $callerfunc['class'] ) ) {
1118                         $func .= $callerfunc['class'] . '::';
1119                 }
1120                 if ( isset( $callerfunc['function'] ) ) {
1121                         $func .= $callerfunc['function'];
1122                 }
1123                 $msg .= " [Called from $func in $file]";
1124         }
1125
1126         if ( $wgDevelopmentWarnings ) {
1127                 trigger_error( $msg, $level );
1128         } else {
1129                 wfDebug( "$msg\n" );
1130         }
1131 }
1132
1133 /**
1134  * Log to a file without getting "file size exceeded" signals.
1135  *
1136  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
1137  * send lines to the specified port, prefixed by the specified prefix and a space.
1138  *
1139  * @param $text String
1140  * @param $file String filename
1141  */
1142 function wfErrorLog( $text, $file ) {
1143         if ( substr( $file, 0, 4 ) == 'udp:' ) {
1144                 # Needs the sockets extension
1145                 if ( preg_match( '!^(tcp|udp):(?://)?\[([0-9a-fA-F:]+)\]:(\d+)(?:/(.*))?$!', $file, $m ) ) {
1146                         // IPv6 bracketed host
1147                         $host = $m[2];
1148                         $port = intval( $m[3] );
1149                         $prefix = isset( $m[4] ) ? $m[4] : false;
1150                         $domain = AF_INET6;
1151                 } elseif ( preg_match( '!^(tcp|udp):(?://)?([a-zA-Z0-9.-]+):(\d+)(?:/(.*))?$!', $file, $m ) ) {
1152                         $host = $m[2];
1153                         if ( !IP::isIPv4( $host ) ) {
1154                                 $host = gethostbyname( $host );
1155                         }
1156                         $port = intval( $m[3] );
1157                         $prefix = isset( $m[4] ) ? $m[4] : false;
1158                         $domain = AF_INET;
1159                 } else {
1160                         throw new MWException( __METHOD__ . ': Invalid UDP specification' );
1161                 }
1162
1163                 // Clean it up for the multiplexer
1164                 if ( strval( $prefix ) !== '' ) {
1165                         $text = preg_replace( '/^/m', $prefix . ' ', $text );
1166
1167                         // Limit to 64KB
1168                         if ( strlen( $text ) > 65506 ) {
1169                                 $text = substr( $text, 0, 65506 );
1170                         }
1171
1172                         if ( substr( $text, -1 ) != "\n" ) {
1173                                 $text .= "\n";
1174                         }
1175                 } elseif ( strlen( $text ) > 65507 ) {
1176                         $text = substr( $text, 0, 65507 );
1177                 }
1178
1179                 $sock = socket_create( $domain, SOCK_DGRAM, SOL_UDP );
1180                 if ( !$sock ) {
1181                         return;
1182                 }
1183
1184                 socket_sendto( $sock, $text, strlen( $text ), 0, $host, $port );
1185                 socket_close( $sock );
1186         } else {
1187                 wfSuppressWarnings();
1188                 $exists = file_exists( $file );
1189                 $size = $exists ? filesize( $file ) : false;
1190                 if ( !$exists || ( $size !== false && $size + strlen( $text ) < 0x7fffffff ) ) {
1191                         file_put_contents( $file, $text, FILE_APPEND );
1192                 }
1193                 wfRestoreWarnings();
1194         }
1195 }
1196
1197 /**
1198  * @todo document
1199  */
1200 function wfLogProfilingData() {
1201         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
1202         global $wgProfileLimit, $wgUser;
1203
1204         $profiler = Profiler::instance();
1205
1206         # Profiling must actually be enabled...
1207         if ( $profiler->isStub() ) {
1208                 return;
1209         }
1210
1211         // Get total page request time and only show pages that longer than
1212         // $wgProfileLimit time (default is 0)
1213         $elapsed = microtime( true ) - $wgRequestTime;
1214         if ( $elapsed <= $wgProfileLimit ) {
1215                 return;
1216         }
1217
1218         $profiler->logData();
1219
1220         // Check whether this should be logged in the debug file.
1221         if ( $wgDebugLogFile == '' || ( !$wgDebugRawPage && wfIsDebugRawPage() ) ) {
1222                 return;
1223         }
1224
1225         $forward = '';
1226         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
1227                 $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
1228         }
1229         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
1230                 $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
1231         }
1232         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
1233                 $forward .= ' from ' . $_SERVER['HTTP_FROM'];
1234         }
1235         if ( $forward ) {
1236                 $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
1237         }
1238         // Don't load $wgUser at this late stage just for statistics purposes
1239         // @todo FIXME: We can detect some anons even if it is not loaded. See User::getId()
1240         if ( $wgUser->isItemLoaded( 'id' ) && $wgUser->isAnon() ) {
1241                 $forward .= ' anon';
1242         }
1243         $log = sprintf( "%s\t%04.3f\t%s\n",
1244                 gmdate( 'YmdHis' ), $elapsed,
1245                 urldecode( $wgRequest->getRequestURL() . $forward ) );
1246
1247         wfErrorLog( $log . $profiler->getOutput(), $wgDebugLogFile );
1248 }
1249
1250 /**
1251  * Increment a statistics counter
1252  *
1253  * @param $key String
1254  * @param $count Int
1255  */
1256 function wfIncrStats( $key, $count = 1 ) {
1257         global $wgStatsMethod;
1258
1259         $count = intval( $count );
1260
1261         if( $wgStatsMethod == 'udp' ) {
1262                 global $wgUDPProfilerHost, $wgUDPProfilerPort, $wgDBname, $wgAggregateStatsID;
1263                 static $socket;
1264
1265                 $id = $wgAggregateStatsID !== false ? $wgAggregateStatsID : $wgDBname;
1266
1267                 if ( !$socket ) {
1268                         $socket = socket_create( AF_INET, SOCK_DGRAM, SOL_UDP );
1269                         $statline = "stats/{$id} - 1 1 1 1 1 -total\n";
1270                         socket_sendto(
1271                                 $socket,
1272                                 $statline,
1273                                 strlen( $statline ),
1274                                 0,
1275                                 $wgUDPProfilerHost,
1276                                 $wgUDPProfilerPort
1277                         );
1278                 }
1279                 $statline = "stats/{$id} - {$count} 1 1 1 1 {$key}\n";
1280                 wfSuppressWarnings();
1281                 socket_sendto(
1282                         $socket,
1283                         $statline,
1284                         strlen( $statline ),
1285                         0,
1286                         $wgUDPProfilerHost,
1287                         $wgUDPProfilerPort
1288                 );
1289                 wfRestoreWarnings();
1290         } elseif( $wgStatsMethod == 'cache' ) {
1291                 global $wgMemc;
1292                 $key = wfMemcKey( 'stats', $key );
1293                 if ( is_null( $wgMemc->incr( $key, $count ) ) ) {
1294                         $wgMemc->add( $key, $count );
1295                 }
1296         } else {
1297                 // Disabled
1298         }
1299 }
1300
1301 /**
1302  * Check if the wiki read-only lock file is present. This can be used to lock
1303  * off editing functions, but doesn't guarantee that the database will not be
1304  * modified.
1305  *
1306  * @return bool
1307  */
1308 function wfReadOnly() {
1309         global $wgReadOnlyFile, $wgReadOnly;
1310
1311         if ( !is_null( $wgReadOnly ) ) {
1312                 return (bool)$wgReadOnly;
1313         }
1314         if ( $wgReadOnlyFile == '' ) {
1315                 return false;
1316         }
1317         // Set $wgReadOnly for faster access next time
1318         if ( is_file( $wgReadOnlyFile ) ) {
1319                 $wgReadOnly = file_get_contents( $wgReadOnlyFile );
1320         } else {
1321                 $wgReadOnly = false;
1322         }
1323         return (bool)$wgReadOnly;
1324 }
1325
1326 /**
1327  * @return bool
1328  */
1329 function wfReadOnlyReason() {
1330         global $wgReadOnly;
1331         wfReadOnly();
1332         return $wgReadOnly;
1333 }
1334
1335 /**
1336  * Return a Language object from $langcode
1337  *
1338  * @param $langcode Mixed: either:
1339  *                  - a Language object
1340  *                  - code of the language to get the message for, if it is
1341  *                    a valid code create a language for that language, if
1342  *                    it is a string but not a valid code then make a basic
1343  *                    language object
1344  *                  - a boolean: if it's false then use the global object for
1345  *                    the current user's language (as a fallback for the old parameter
1346  *                    functionality), or if it is true then use global object
1347  *                    for the wiki's content language.
1348  * @return Language object
1349  */
1350 function wfGetLangObj( $langcode = false ) {
1351         # Identify which language to get or create a language object for.
1352         # Using is_object here due to Stub objects.
1353         if( is_object( $langcode ) ) {
1354                 # Great, we already have the object (hopefully)!
1355                 return $langcode;
1356         }
1357
1358         global $wgContLang, $wgLanguageCode;
1359         if( $langcode === true || $langcode === $wgLanguageCode ) {
1360                 # $langcode is the language code of the wikis content language object.
1361                 # or it is a boolean and value is true
1362                 return $wgContLang;
1363         }
1364
1365         global $wgLang;
1366         if( $langcode === false || $langcode === $wgLang->getCode() ) {
1367                 # $langcode is the language code of user language object.
1368                 # or it was a boolean and value is false
1369                 return $wgLang;
1370         }
1371
1372         $validCodes = array_keys( Language::fetchLanguageNames() );
1373         if( in_array( $langcode, $validCodes ) ) {
1374                 # $langcode corresponds to a valid language.
1375                 return Language::factory( $langcode );
1376         }
1377
1378         # $langcode is a string, but not a valid language code; use content language.
1379         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
1380         return $wgContLang;
1381 }
1382
1383 /**
1384  * Old function when $wgBetterDirectionality existed
1385  * All usage removed, wfUILang can be removed in near future
1386  *
1387  * @deprecated since 1.18
1388  * @return Language
1389  */
1390 function wfUILang() {
1391         wfDeprecated( __METHOD__, '1.18' );
1392         global $wgLang;
1393         return $wgLang;
1394 }
1395
1396 /**
1397  * This is the new function for getting translated interface messages.
1398  * See the Message class for documentation how to use them.
1399  * The intention is that this function replaces all old wfMsg* functions.
1400  * @param $key \string Message key.
1401  * Varargs: normal message parameters.
1402  * @return Message
1403  * @since 1.17
1404  */
1405 function wfMessage( $key /*...*/) {
1406         $params = func_get_args();
1407         array_shift( $params );
1408         if ( isset( $params[0] ) && is_array( $params[0] ) ) {
1409                 $params = $params[0];
1410         }
1411         return new Message( $key, $params );
1412 }
1413
1414 /**
1415  * This function accepts multiple message keys and returns a message instance
1416  * for the first message which is non-empty. If all messages are empty then an
1417  * instance of the first message key is returned.
1418  * @param varargs: message keys
1419  * @return Message
1420  * @since 1.18
1421  */
1422 function wfMessageFallback( /*...*/ ) {
1423         $args = func_get_args();
1424         return MWFunction::callArray( 'Message::newFallbackSequence', $args );
1425 }
1426
1427 /**
1428  * Get a message from anywhere, for the current user language.
1429  *
1430  * Use wfMsgForContent() instead if the message should NOT
1431  * change depending on the user preferences.
1432  *
1433  * @param $key String: lookup key for the message, usually
1434  *    defined in languages/Language.php
1435  *
1436  * Parameters to the message, which can be used to insert variable text into
1437  * it, can be passed to this function in the following formats:
1438  * - One per argument, starting at the second parameter
1439  * - As an array in the second parameter
1440  * These are not shown in the function definition.
1441  *
1442  * @return String
1443  */
1444 function wfMsg( $key ) {
1445         $args = func_get_args();
1446         array_shift( $args );
1447         return wfMsgReal( $key, $args );
1448 }
1449
1450 /**
1451  * Same as above except doesn't transform the message
1452  *
1453  * @param $key String
1454  * @return String
1455  */
1456 function wfMsgNoTrans( $key ) {
1457         $args = func_get_args();
1458         array_shift( $args );
1459         return wfMsgReal( $key, $args, true, false, false );
1460 }
1461
1462 /**
1463  * Get a message from anywhere, for the current global language
1464  * set with $wgLanguageCode.
1465  *
1466  * Use this if the message should NOT change dependent on the
1467  * language set in the user's preferences. This is the case for
1468  * most text written into logs, as well as link targets (such as
1469  * the name of the copyright policy page). Link titles, on the
1470  * other hand, should be shown in the UI language.
1471  *
1472  * Note that MediaWiki allows users to change the user interface
1473  * language in their preferences, but a single installation
1474  * typically only contains content in one language.
1475  *
1476  * Be wary of this distinction: If you use wfMsg() where you should
1477  * use wfMsgForContent(), a user of the software may have to
1478  * customize potentially hundreds of messages in
1479  * order to, e.g., fix a link in every possible language.
1480  *
1481  * @param $key String: lookup key for the message, usually
1482  *     defined in languages/Language.php
1483  * @return String
1484  */
1485 function wfMsgForContent( $key ) {
1486         global $wgForceUIMsgAsContentMsg;
1487         $args = func_get_args();
1488         array_shift( $args );
1489         $forcontent = true;
1490         if( is_array( $wgForceUIMsgAsContentMsg ) &&
1491                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
1492         {
1493                 $forcontent = false;
1494         }
1495         return wfMsgReal( $key, $args, true, $forcontent );
1496 }
1497
1498 /**
1499  * Same as above except doesn't transform the message
1500  *
1501  * @param $key String
1502  * @return String
1503  */
1504 function wfMsgForContentNoTrans( $key ) {
1505         global $wgForceUIMsgAsContentMsg;
1506         $args = func_get_args();
1507         array_shift( $args );
1508         $forcontent = true;
1509         if( is_array( $wgForceUIMsgAsContentMsg ) &&
1510                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
1511         {
1512                 $forcontent = false;
1513         }
1514         return wfMsgReal( $key, $args, true, $forcontent, false );
1515 }
1516
1517 /**
1518  * Really get a message
1519  *
1520  * @param $key String: key to get.
1521  * @param $args
1522  * @param $useDB Boolean
1523  * @param $forContent Mixed: Language code, or false for user lang, true for content lang.
1524  * @param $transform Boolean: Whether or not to transform the message.
1525  * @return String: the requested message.
1526  */
1527 function wfMsgReal( $key, $args, $useDB = true, $forContent = false, $transform = true ) {
1528         wfProfileIn( __METHOD__ );
1529         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
1530         $message = wfMsgReplaceArgs( $message, $args );
1531         wfProfileOut( __METHOD__ );
1532         return $message;
1533 }
1534
1535 /**
1536  * Fetch a message string value, but don't replace any keys yet.
1537  *
1538  * @param $key String
1539  * @param $useDB Bool
1540  * @param $langCode String: Code of the language to get the message for, or
1541  *                  behaves as a content language switch if it is a boolean.
1542  * @param $transform Boolean: whether to parse magic words, etc.
1543  * @return string
1544  */
1545 function wfMsgGetKey( $key, $useDB = true, $langCode = false, $transform = true ) {
1546         wfRunHooks( 'NormalizeMessageKey', array( &$key, &$useDB, &$langCode, &$transform ) );
1547
1548         $cache = MessageCache::singleton();
1549         $message = $cache->get( $key, $useDB, $langCode );
1550         if( $message === false ) {
1551                 $message = '&lt;' . htmlspecialchars( $key ) . '&gt;';
1552         } elseif ( $transform ) {
1553                 $message = $cache->transform( $message );
1554         }
1555         return $message;
1556 }
1557
1558 /**
1559  * Replace message parameter keys on the given formatted output.
1560  *
1561  * @param $message String
1562  * @param $args Array
1563  * @return string
1564  * @private
1565  */
1566 function wfMsgReplaceArgs( $message, $args ) {
1567         # Fix windows line-endings
1568         # Some messages are split with explode("\n", $msg)
1569         $message = str_replace( "\r", '', $message );
1570
1571         // Replace arguments
1572         if ( count( $args ) ) {
1573                 if ( is_array( $args[0] ) ) {
1574                         $args = array_values( $args[0] );
1575                 }
1576                 $replacementKeys = array();
1577                 foreach( $args as $n => $param ) {
1578                         $replacementKeys['$' . ( $n + 1 )] = $param;
1579                 }
1580                 $message = strtr( $message, $replacementKeys );
1581         }
1582
1583         return $message;
1584 }
1585
1586 /**
1587  * Return an HTML-escaped version of a message.
1588  * Parameter replacements, if any, are done *after* the HTML-escaping,
1589  * so parameters may contain HTML (eg links or form controls). Be sure
1590  * to pre-escape them if you really do want plaintext, or just wrap
1591  * the whole thing in htmlspecialchars().
1592  *
1593  * @param $key String
1594  * @param string ... parameters
1595  * @return string
1596  */
1597 function wfMsgHtml( $key ) {
1598         $args = func_get_args();
1599         array_shift( $args );
1600         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key ) ), $args );
1601 }
1602
1603 /**
1604  * Return an HTML version of message
1605  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
1606  * so parameters may contain HTML (eg links or form controls). Be sure
1607  * to pre-escape them if you really do want plaintext, or just wrap
1608  * the whole thing in htmlspecialchars().
1609  *
1610  * @param $key String
1611  * @param string ... parameters
1612  * @return string
1613  */
1614 function wfMsgWikiHtml( $key ) {
1615         $args = func_get_args();
1616         array_shift( $args );
1617         return wfMsgReplaceArgs(
1618                 MessageCache::singleton()->parse( wfMsgGetKey( $key ), null,
1619                 /* can't be set to false */ true, /* interface */ true )->getText(),
1620                 $args );
1621 }
1622
1623 /**
1624  * Returns message in the requested format
1625  * @param $key String: key of the message
1626  * @param $options Array: processing rules. Can take the following options:
1627  *   <i>parse</i>: parses wikitext to HTML
1628  *   <i>parseinline</i>: parses wikitext to HTML and removes the surrounding
1629  *       p's added by parser or tidy
1630  *   <i>escape</i>: filters message through htmlspecialchars
1631  *   <i>escapenoentities</i>: same, but allows entity references like &#160; through
1632  *   <i>replaceafter</i>: parameters are substituted after parsing or escaping
1633  *   <i>parsemag</i>: transform the message using magic phrases
1634  *   <i>content</i>: fetch message for content language instead of interface
1635  * Also can accept a single associative argument, of the form 'language' => 'xx':
1636  *   <i>language</i>: Language object or language code to fetch message for
1637  *       (overriden by <i>content</i>).
1638  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
1639  *
1640  * @return String
1641  */
1642 function wfMsgExt( $key, $options ) {
1643         $args = func_get_args();
1644         array_shift( $args );
1645         array_shift( $args );
1646         $options = (array)$options;
1647
1648         foreach( $options as $arrayKey => $option ) {
1649                 if( !preg_match( '/^[0-9]+|language$/', $arrayKey ) ) {
1650                         # An unknown index, neither numeric nor "language"
1651                         wfWarn( "wfMsgExt called with incorrect parameter key $arrayKey", 1, E_USER_WARNING );
1652                 } elseif( preg_match( '/^[0-9]+$/', $arrayKey ) && !in_array( $option,
1653                 array( 'parse', 'parseinline', 'escape', 'escapenoentities',
1654                 'replaceafter', 'parsemag', 'content' ) ) ) {
1655                         # A numeric index with unknown value
1656                         wfWarn( "wfMsgExt called with incorrect parameter $option", 1, E_USER_WARNING );
1657                 }
1658         }
1659
1660         if( in_array( 'content', $options, true ) ) {
1661                 $forContent = true;
1662                 $langCode = true;
1663                 $langCodeObj = null;
1664         } elseif( array_key_exists( 'language', $options ) ) {
1665                 $forContent = false;
1666                 $langCode = wfGetLangObj( $options['language'] );
1667                 $langCodeObj = $langCode;
1668         } else {
1669                 $forContent = false;
1670                 $langCode = false;
1671                 $langCodeObj = null;
1672         }
1673
1674         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
1675
1676         if( !in_array( 'replaceafter', $options, true ) ) {
1677                 $string = wfMsgReplaceArgs( $string, $args );
1678         }
1679
1680         $messageCache = MessageCache::singleton();
1681         $parseInline = in_array( 'parseinline', $options, true );
1682         if( in_array( 'parse', $options, true ) || $parseInline ) {
1683                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj );
1684                 if ( $string instanceof ParserOutput ) {
1685                         $string = $string->getText();
1686                 }
1687
1688                 if ( $parseInline ) {
1689                         $m = array();
1690                         if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
1691                                 $string = $m[1];
1692                         }
1693                 }
1694         } elseif ( in_array( 'parsemag', $options, true ) ) {
1695                 $string = $messageCache->transform( $string,
1696                                 !$forContent, $langCodeObj );
1697         }
1698
1699         if ( in_array( 'escape', $options, true ) ) {
1700                 $string = htmlspecialchars ( $string );
1701         } elseif ( in_array( 'escapenoentities', $options, true ) ) {
1702                 $string = Sanitizer::escapeHtmlAllowEntities( $string );
1703         }
1704
1705         if( in_array( 'replaceafter', $options, true ) ) {
1706                 $string = wfMsgReplaceArgs( $string, $args );
1707         }
1708
1709         return $string;
1710 }
1711
1712 /**
1713  * Since wfMsg() and co suck, they don't return false if the message key they
1714  * looked up didn't exist but a XHTML string, this function checks for the
1715  * nonexistance of messages by checking the MessageCache::get() result directly.
1716  *
1717  * @param $key      String: the message key looked up
1718  * @return Boolean True if the message *doesn't* exist.
1719  */
1720 function wfEmptyMsg( $key ) {
1721         return MessageCache::singleton()->get( $key, /*useDB*/true, /*content*/false ) === false;
1722 }
1723
1724 /**
1725  * Throw a debugging exception. This function previously once exited the process,
1726  * but now throws an exception instead, with similar results.
1727  *
1728  * @param $msg String: message shown when dying.
1729  */
1730 function wfDebugDieBacktrace( $msg = '' ) {
1731         throw new MWException( $msg );
1732 }
1733
1734 /**
1735  * Fetch server name for use in error reporting etc.
1736  * Use real server name if available, so we know which machine
1737  * in a server farm generated the current page.
1738  *
1739  * @return string
1740  */
1741 function wfHostname() {
1742         static $host;
1743         if ( is_null( $host ) ) {
1744                 if ( function_exists( 'posix_uname' ) ) {
1745                         // This function not present on Windows
1746                         $uname = posix_uname();
1747                 } else {
1748                         $uname = false;
1749                 }
1750                 if( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1751                         $host = $uname['nodename'];
1752                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1753                         # Windows computer name
1754                         $host = getenv( 'COMPUTERNAME' );
1755                 } else {
1756                         # This may be a virtual server.
1757                         $host = $_SERVER['SERVER_NAME'];
1758                 }
1759         }
1760         return $host;
1761 }
1762
1763 /**
1764  * Returns a HTML comment with the elapsed time since request.
1765  * This method has no side effects.
1766  *
1767  * @return string
1768  */
1769 function wfReportTime() {
1770         global $wgRequestTime, $wgShowHostnames;
1771
1772         $elapsed = microtime( true ) - $wgRequestTime;
1773
1774         return $wgShowHostnames
1775                 ? sprintf( '<!-- Served by %s in %01.3f secs. -->', wfHostname(), $elapsed )
1776                 : sprintf( '<!-- Served in %01.3f secs. -->', $elapsed );
1777 }
1778
1779 /**
1780  * Safety wrapper for debug_backtrace().
1781  *
1782  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
1783  * murky circumstances, which may be triggered in part by stub objects
1784  * or other fancy talkin'.
1785  *
1786  * Will return an empty array if Zend Optimizer is detected or if
1787  * debug_backtrace is disabled, otherwise the output from
1788  * debug_backtrace() (trimmed).
1789  *
1790  * @param $limit int This parameter can be used to limit the number of stack frames returned
1791  *
1792  * @return array of backtrace information
1793  */
1794 function wfDebugBacktrace( $limit = 0 ) {
1795         static $disabled = null;
1796
1797         if( extension_loaded( 'Zend Optimizer' ) ) {
1798                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
1799                 return array();
1800         }
1801
1802         if ( is_null( $disabled ) ) {
1803                 $disabled = false;
1804                 $functions = explode( ',', ini_get( 'disable_functions' ) );
1805                 $functions = array_map( 'trim', $functions );
1806                 $functions = array_map( 'strtolower', $functions );
1807                 if ( in_array( 'debug_backtrace', $functions ) ) {
1808                         wfDebug( "debug_backtrace is in disabled_functions\n" );
1809                         $disabled = true;
1810                 }
1811         }
1812         if ( $disabled ) {
1813                 return array();
1814         }
1815
1816         if ( $limit && version_compare( PHP_VERSION, '5.4.0', '>=' ) ) {
1817                 return array_slice( debug_backtrace( DEBUG_BACKTRACE_PROVIDE_OBJECT, $limit ), 1 );
1818         } else {
1819                 return array_slice( debug_backtrace(), 1 );
1820         }
1821 }
1822
1823 /**
1824  * Get a debug backtrace as a string
1825  *
1826  * @return string
1827  */
1828 function wfBacktrace() {
1829         global $wgCommandLineMode;
1830
1831         if ( $wgCommandLineMode ) {
1832                 $msg = '';
1833         } else {
1834                 $msg = "<ul>\n";
1835         }
1836         $backtrace = wfDebugBacktrace();
1837         foreach( $backtrace as $call ) {
1838                 if( isset( $call['file'] ) ) {
1839                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
1840                         $file = $f[count( $f ) - 1];
1841                 } else {
1842                         $file = '-';
1843                 }
1844                 if( isset( $call['line'] ) ) {
1845                         $line = $call['line'];
1846                 } else {
1847                         $line = '-';
1848                 }
1849                 if ( $wgCommandLineMode ) {
1850                         $msg .= "$file line $line calls ";
1851                 } else {
1852                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
1853                 }
1854                 if( !empty( $call['class'] ) ) {
1855                         $msg .= $call['class'] . $call['type'];
1856                 }
1857                 $msg .= $call['function'] . '()';
1858
1859                 if ( $wgCommandLineMode ) {
1860                         $msg .= "\n";
1861                 } else {
1862                         $msg .= "</li>\n";
1863                 }
1864         }
1865         if ( $wgCommandLineMode ) {
1866                 $msg .= "\n";
1867         } else {
1868                 $msg .= "</ul>\n";
1869         }
1870
1871         return $msg;
1872 }
1873
1874 /**
1875  * Get the name of the function which called this function
1876  *
1877  * @param $level Int
1878  * @return Bool|string
1879  */
1880 function wfGetCaller( $level = 2 ) {
1881         $backtrace = wfDebugBacktrace( $level );
1882         if ( isset( $backtrace[$level] ) ) {
1883                 return wfFormatStackFrame( $backtrace[$level] );
1884         } else {
1885                 $caller = 'unknown';
1886         }
1887         return $caller;
1888 }
1889
1890 /**
1891  * Return a string consisting of callers in the stack. Useful sometimes
1892  * for profiling specific points.
1893  *
1894  * @param $limit int The maximum depth of the stack frame to return, or false for
1895  *               the entire stack.
1896  * @return String
1897  */
1898 function wfGetAllCallers( $limit = 3 ) {
1899         $trace = array_reverse( wfDebugBacktrace() );
1900         if ( !$limit || $limit > count( $trace ) - 1 ) {
1901                 $limit = count( $trace ) - 1;
1902         }
1903         $trace = array_slice( $trace, -$limit - 1, $limit );
1904         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1905 }
1906
1907 /**
1908  * Return a string representation of frame
1909  *
1910  * @param $frame Array
1911  * @return Bool
1912  */
1913 function wfFormatStackFrame( $frame ) {
1914         return isset( $frame['class'] ) ?
1915                 $frame['class'] . '::' . $frame['function'] :
1916                 $frame['function'];
1917 }
1918
1919
1920 /* Some generic result counters, pulled out of SearchEngine */
1921
1922
1923 /**
1924  * @todo document
1925  *
1926  * @param $offset Int
1927  * @param $limit Int
1928  * @return String
1929  */
1930 function wfShowingResults( $offset, $limit ) {
1931         global $wgLang;
1932         return wfMsgExt(
1933                 'showingresults',
1934                 array( 'parseinline' ),
1935                 $wgLang->formatNum( $limit ),
1936                 $wgLang->formatNum( $offset + 1 )
1937         );
1938 }
1939
1940 /**
1941  * Generate (prev x| next x) (20|50|100...) type links for paging
1942  *
1943  * @param $offset String
1944  * @param $limit Integer
1945  * @param $link String
1946  * @param $query String: optional URL query parameter string
1947  * @param $atend Bool: optional param for specified if this is the last page
1948  * @return String
1949  * @deprecated in 1.19; use Language::viewPrevNext() instead
1950  */
1951 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
1952         wfDeprecated( __METHOD__, '1.19' );
1953
1954         global $wgLang;
1955
1956         $query = wfCgiToArray( $query );
1957
1958         if( is_object( $link ) ) {
1959                 $title = $link;
1960         } else {
1961                 $title = Title::newFromText( $link );
1962                 if( is_null( $title ) ) {
1963                         return false;
1964                 }
1965         }
1966
1967         return $wgLang->viewPrevNext( $title, $offset, $limit, $query, $atend );
1968 }
1969
1970 /**
1971  * Make a list item, used by various special pages
1972  *
1973  * @param $page String Page link
1974  * @param $details String Text between brackets
1975  * @param $oppositedm Boolean   Add the direction mark opposite to your
1976  *                                                              language, to display text properly
1977  * @return String
1978  * @deprecated since 1.19; use Language::specialList() instead
1979  */
1980 function wfSpecialList( $page, $details, $oppositedm = true ) {
1981         wfDeprecated( __METHOD__, '1.19' );
1982
1983         global $wgLang;
1984         return $wgLang->specialList( $page, $details, $oppositedm );
1985 }
1986
1987 /**
1988  * @todo document
1989  * @todo FIXME: We may want to blacklist some broken browsers
1990  *
1991  * @param $force Bool
1992  * @return bool Whereas client accept gzip compression
1993  */
1994 function wfClientAcceptsGzip( $force = false ) {
1995         static $result = null;
1996         if ( $result === null || $force ) {
1997                 $result = false;
1998                 if( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1999                         # @todo FIXME: We may want to blacklist some broken browsers
2000                         $m = array();
2001                         if( preg_match(
2002                                 '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
2003                                 $_SERVER['HTTP_ACCEPT_ENCODING'],
2004                                 $m )
2005                         )
2006                         {
2007                                 if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
2008                                         $result = false;
2009                                         return $result;
2010                                 }
2011                                 wfDebug( "wfClientAcceptsGzip: client accepts gzip.\n" );
2012                                 $result = true;
2013                         }
2014                 }
2015         }
2016         return $result;
2017 }
2018
2019 /**
2020  * Obtain the offset and limit values from the request string;
2021  * used in special pages
2022  *
2023  * @param $deflimit Int default limit if none supplied
2024  * @param $optionname String Name of a user preference to check against
2025  * @return array
2026  *
2027  */
2028 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
2029         global $wgRequest;
2030         return $wgRequest->getLimitOffset( $deflimit, $optionname );
2031 }
2032
2033 /**
2034  * Escapes the given text so that it may be output using addWikiText()
2035  * without any linking, formatting, etc. making its way through. This
2036  * is achieved by substituting certain characters with HTML entities.
2037  * As required by the callers, <nowiki> is not used.
2038  *
2039  * @param $text String: text to be escaped
2040  * @return String
2041  */
2042 function wfEscapeWikiText( $text ) {
2043         $text = strtr( "\n$text", array(
2044                 '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
2045                 '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
2046                 '{' => '&#123;', '|' => '&#124;', '}' => '&#125;',
2047                 "\n#" => "\n&#35;", "\n*" => "\n&#42;",
2048                 "\n:" => "\n&#58;", "\n;" => "\n&#59;",
2049                 '://' => '&#58;//', 'ISBN ' => 'ISBN&#32;', 'RFC ' => 'RFC&#32;',
2050         ) );
2051         return substr( $text, 1 );
2052 }
2053
2054 /**
2055  * Get the current unix timetstamp with microseconds.  Useful for profiling
2056  * @return Float
2057  */
2058 function wfTime() {
2059         return microtime( true );
2060 }
2061
2062 /**
2063  * Sets dest to source and returns the original value of dest
2064  * If source is NULL, it just returns the value, it doesn't set the variable
2065  * If force is true, it will set the value even if source is NULL
2066  *
2067  * @param $dest Mixed
2068  * @param $source Mixed
2069  * @param $force Bool
2070  * @return Mixed
2071  */
2072 function wfSetVar( &$dest, $source, $force = false ) {
2073         $temp = $dest;
2074         if ( !is_null( $source ) || $force ) {
2075                 $dest = $source;
2076         }
2077         return $temp;
2078 }
2079
2080 /**
2081  * As for wfSetVar except setting a bit
2082  *
2083  * @param $dest Int
2084  * @param $bit Int
2085  * @param $state Bool
2086  *
2087  * @return bool
2088  */
2089 function wfSetBit( &$dest, $bit, $state = true ) {
2090         $temp = (bool)( $dest & $bit );
2091         if ( !is_null( $state ) ) {
2092                 if ( $state ) {
2093                         $dest |= $bit;
2094                 } else {
2095                         $dest &= ~$bit;
2096                 }
2097         }
2098         return $temp;
2099 }
2100
2101 /**
2102  * A wrapper around the PHP function var_export().
2103  * Either print it or add it to the regular output ($wgOut).
2104  *
2105  * @param $var mixed A PHP variable to dump.
2106  */
2107 function wfVarDump( $var ) {
2108         global $wgOut;
2109         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
2110         if ( headers_sent() || !isset( $wgOut ) || !is_object( $wgOut ) ) {
2111                 print $s;
2112         } else {
2113                 $wgOut->addHTML( $s );
2114         }
2115 }
2116
2117 /**
2118  * Provide a simple HTTP error.
2119  *
2120  * @param $code Int|String
2121  * @param $label String
2122  * @param $desc String
2123  */
2124 function wfHttpError( $code, $label, $desc ) {
2125         global $wgOut;
2126         $wgOut->disable();
2127         header( "HTTP/1.0 $code $label" );
2128         header( "Status: $code $label" );
2129         $wgOut->sendCacheControl();
2130
2131         header( 'Content-type: text/html; charset=utf-8' );
2132         print "<!doctype html>" .
2133                 '<html><head><title>' .
2134                 htmlspecialchars( $label ) .
2135                 '</title></head><body><h1>' .
2136                 htmlspecialchars( $label ) .
2137                 '</h1><p>' .
2138                 nl2br( htmlspecialchars( $desc ) ) .
2139                 "</p></body></html>\n";
2140 }
2141
2142 /**
2143  * Clear away any user-level output buffers, discarding contents.
2144  *
2145  * Suitable for 'starting afresh', for instance when streaming
2146  * relatively large amounts of data without buffering, or wanting to
2147  * output image files without ob_gzhandler's compression.
2148  *
2149  * The optional $resetGzipEncoding parameter controls suppression of
2150  * the Content-Encoding header sent by ob_gzhandler; by default it
2151  * is left. See comments for wfClearOutputBuffers() for why it would
2152  * be used.
2153  *
2154  * Note that some PHP configuration options may add output buffer
2155  * layers which cannot be removed; these are left in place.
2156  *
2157  * @param $resetGzipEncoding Bool
2158  */
2159 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
2160         if( $resetGzipEncoding ) {
2161                 // Suppress Content-Encoding and Content-Length
2162                 // headers from 1.10+s wfOutputHandler
2163                 global $wgDisableOutputCompression;
2164                 $wgDisableOutputCompression = true;
2165         }
2166         while( $status = ob_get_status() ) {
2167                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
2168                         // Probably from zlib.output_compression or other
2169                         // PHP-internal setting which can't be removed.
2170                         //
2171                         // Give up, and hope the result doesn't break
2172                         // output behavior.
2173                         break;
2174                 }
2175                 if( !ob_end_clean() ) {
2176                         // Could not remove output buffer handler; abort now
2177                         // to avoid getting in some kind of infinite loop.
2178                         break;
2179                 }
2180                 if( $resetGzipEncoding ) {
2181                         if( $status['name'] == 'ob_gzhandler' ) {
2182                                 // Reset the 'Content-Encoding' field set by this handler
2183                                 // so we can start fresh.
2184                                 if ( function_exists( 'header_remove' ) ) {
2185                                         // Available since PHP 5.3.0
2186                                         header_remove( 'Content-Encoding' );
2187                                 } else {
2188                                         // We need to provide a valid content-coding. See bug 28069
2189                                         header( 'Content-Encoding: identity' );
2190                                 }
2191                                 break;
2192                         }
2193                 }
2194         }
2195 }
2196
2197 /**
2198  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
2199  *
2200  * Clear away output buffers, but keep the Content-Encoding header
2201  * produced by ob_gzhandler, if any.
2202  *
2203  * This should be used for HTTP 304 responses, where you need to
2204  * preserve the Content-Encoding header of the real result, but
2205  * also need to suppress the output of ob_gzhandler to keep to spec
2206  * and avoid breaking Firefox in rare cases where the headers and
2207  * body are broken over two packets.
2208  */
2209 function wfClearOutputBuffers() {
2210         wfResetOutputBuffers( false );
2211 }
2212
2213 /**
2214  * Converts an Accept-* header into an array mapping string values to quality
2215  * factors
2216  *
2217  * @param $accept String
2218  * @param $def String default
2219  * @return Array
2220  */
2221 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
2222         # No arg means accept anything (per HTTP spec)
2223         if( !$accept ) {
2224                 return array( $def => 1.0 );
2225         }
2226
2227         $prefs = array();
2228
2229         $parts = explode( ',', $accept );
2230
2231         foreach( $parts as $part ) {
2232                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
2233                 $values = explode( ';', trim( $part ) );
2234                 $match = array();
2235                 if ( count( $values ) == 1 ) {
2236                         $prefs[$values[0]] = 1.0;
2237                 } elseif ( preg_match( '/q\s*=\s*(\d*\.\d+)/', $values[1], $match ) ) {
2238                         $prefs[$values[0]] = floatval( $match[1] );
2239                 }
2240         }
2241
2242         return $prefs;
2243 }
2244
2245 /**
2246  * Checks if a given MIME type matches any of the keys in the given
2247  * array. Basic wildcards are accepted in the array keys.
2248  *
2249  * Returns the matching MIME type (or wildcard) if a match, otherwise
2250  * NULL if no match.
2251  *
2252  * @param $type String
2253  * @param $avail Array
2254  * @return string
2255  * @private
2256  */
2257 function mimeTypeMatch( $type, $avail ) {
2258         if( array_key_exists( $type, $avail ) ) {
2259                 return $type;
2260         } else {
2261                 $parts = explode( '/', $type );
2262                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
2263                         return $parts[0] . '/*';
2264                 } elseif( array_key_exists( '*/*', $avail ) ) {
2265                         return '*/*';
2266                 } else {
2267                         return null;
2268                 }
2269         }
2270 }
2271
2272 /**
2273  * Returns the 'best' match between a client's requested internet media types
2274  * and the server's list of available types. Each list should be an associative
2275  * array of type to preference (preference is a float between 0.0 and 1.0).
2276  * Wildcards in the types are acceptable.
2277  *
2278  * @param $cprefs Array: client's acceptable type list
2279  * @param $sprefs Array: server's offered types
2280  * @return string
2281  *
2282  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
2283  * XXX: generalize to negotiate other stuff
2284  */
2285 function wfNegotiateType( $cprefs, $sprefs ) {
2286         $combine = array();
2287
2288         foreach( array_keys( $sprefs ) as $type ) {
2289                 $parts = explode( '/', $type );
2290                 if( $parts[1] != '*' ) {
2291                         $ckey = mimeTypeMatch( $type, $cprefs );
2292                         if( $ckey ) {
2293                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
2294                         }
2295                 }
2296         }
2297
2298         foreach( array_keys( $cprefs ) as $type ) {
2299                 $parts = explode( '/', $type );
2300                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
2301                         $skey = mimeTypeMatch( $type, $sprefs );
2302                         if( $skey ) {
2303                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
2304                         }
2305                 }
2306         }
2307
2308         $bestq = 0;
2309         $besttype = null;
2310
2311         foreach( array_keys( $combine ) as $type ) {
2312                 if( $combine[$type] > $bestq ) {
2313                         $besttype = $type;
2314                         $bestq = $combine[$type];
2315                 }
2316         }
2317
2318         return $besttype;
2319 }
2320
2321 /**
2322  * Reference-counted warning suppression
2323  *
2324  * @param $end Bool
2325  */
2326 function wfSuppressWarnings( $end = false ) {
2327         static $suppressCount = 0;
2328         static $originalLevel = false;
2329
2330         if ( $end ) {
2331                 if ( $suppressCount ) {
2332                         --$suppressCount;
2333                         if ( !$suppressCount ) {
2334                                 error_reporting( $originalLevel );
2335                         }
2336                 }
2337         } else {
2338                 if ( !$suppressCount ) {
2339                         // E_DEPRECATED is undefined in PHP 5.2
2340                         if( !defined( 'E_DEPRECATED' ) ) {
2341                                 define( 'E_DEPRECATED', 8192 );
2342                         }
2343                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE | E_USER_WARNING | E_USER_NOTICE | E_DEPRECATED ) );
2344                 }
2345                 ++$suppressCount;
2346         }
2347 }
2348
2349 /**
2350  * Restore error level to previous value
2351  */
2352 function wfRestoreWarnings() {
2353         wfSuppressWarnings( true );
2354 }
2355
2356 # Autodetect, convert and provide timestamps of various types
2357
2358 /**
2359  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
2360  */
2361 define( 'TS_UNIX', 0 );
2362
2363 /**
2364  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
2365  */
2366 define( 'TS_MW', 1 );
2367
2368 /**
2369  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
2370  */
2371 define( 'TS_DB', 2 );
2372
2373 /**
2374  * RFC 2822 format, for E-mail and HTTP headers
2375  */
2376 define( 'TS_RFC2822', 3 );
2377
2378 /**
2379  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
2380  *
2381  * This is used by Special:Export
2382  */
2383 define( 'TS_ISO_8601', 4 );
2384
2385 /**
2386  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
2387  *
2388  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
2389  *       DateTime tag and page 36 for the DateTimeOriginal and
2390  *       DateTimeDigitized tags.
2391  */
2392 define( 'TS_EXIF', 5 );
2393
2394 /**
2395  * Oracle format time.
2396  */
2397 define( 'TS_ORACLE', 6 );
2398
2399 /**
2400  * Postgres format time.
2401  */
2402 define( 'TS_POSTGRES', 7 );
2403
2404 /**
2405  * DB2 format time
2406  */
2407 define( 'TS_DB2', 8 );
2408
2409 /**
2410  * ISO 8601 basic format with no timezone: 19860209T200000Z.  This is used by ResourceLoader
2411  */
2412 define( 'TS_ISO_8601_BASIC', 9 );
2413
2414 /**
2415  * Get a timestamp string in one of various formats
2416  *
2417  * @param $outputtype Mixed: A timestamp in one of the supported formats, the
2418  *                    function will autodetect which format is supplied and act
2419  *                    accordingly.
2420  * @param $ts Mixed: the timestamp to convert or 0 for the current timestamp
2421  * @return Mixed: String / false The same date in the format specified in $outputtype or false
2422  */
2423 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
2424         $uts = 0;
2425         $da = array();
2426         $strtime = '';
2427
2428         if ( !$ts ) { // We want to catch 0, '', null... but not date strings starting with a letter.
2429                 $uts = time();
2430                 $strtime = "@$uts";
2431         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2432                 # TS_DB
2433         } elseif ( preg_match( '/^(\d{4}):(\d\d):(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2434                 # TS_EXIF
2435         } elseif ( preg_match( '/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/D', $ts, $da ) ) {
2436                 # TS_MW
2437         } elseif ( preg_match( '/^-?\d{1,13}$/D', $ts ) ) {
2438                 # TS_UNIX
2439                 $uts = $ts;
2440                 $strtime = "@$ts"; // http://php.net/manual/en/datetime.formats.compound.php
2441         } elseif ( preg_match( '/^\d{2}-\d{2}-\d{4} \d{2}:\d{2}:\d{2}.\d{6}$/', $ts ) ) {
2442                 # TS_ORACLE // session altered to DD-MM-YYYY HH24:MI:SS.FF6
2443                 $strtime = preg_replace( '/(\d\d)\.(\d\d)\.(\d\d)(\.(\d+))?/', "$1:$2:$3",
2444                                 str_replace( '+00:00', 'UTC', $ts ) );
2445         } elseif ( preg_match( '/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2446                 # TS_ISO_8601
2447         } elseif ( preg_match( '/^(\d{4})(\d{2})(\d{2})T(\d{2})(\d{2})(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2448                 #TS_ISO_8601_BASIC
2449         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d*[\+\- ](\d\d)$/', $ts, $da ) ) {
2450                 # TS_POSTGRES
2451         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d* GMT$/', $ts, $da ) ) {
2452                 # TS_POSTGRES
2453         } elseif (preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.\d\d\d$/', $ts, $da ) ) {
2454                 # TS_DB2
2455         } elseif ( preg_match( '/^[ \t\r\n]*([A-Z][a-z]{2},[ \t\r\n]*)?' . # Day of week
2456                                                         '\d\d?[ \t\r\n]*[A-Z][a-z]{2}[ \t\r\n]*\d{2}(?:\d{2})?' .  # dd Mon yyyy
2457                                                         '[ \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
2458                 # TS_RFC2822, accepting a trailing comment. See http://www.squid-cache.org/mail-archive/squid-users/200307/0122.html / r77171
2459                 # The regex is a superset of rfc2822 for readability
2460                 $strtime = strtok( $ts, ';' );
2461         } 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 ) ) {
2462                 # TS_RFC850
2463                 $strtime = $ts;
2464         } 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 ) ) {
2465                 # asctime
2466                 $strtime = $ts;
2467         } else {
2468                 # Bogus value...
2469                 wfDebug("wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n");
2470
2471                 return false;
2472         }
2473
2474         static $formats = array(
2475                 TS_UNIX => 'U',
2476                 TS_MW => 'YmdHis',
2477                 TS_DB => 'Y-m-d H:i:s',
2478                 TS_ISO_8601 => 'Y-m-d\TH:i:s\Z',
2479                 TS_ISO_8601_BASIC => 'Ymd\THis\Z',
2480                 TS_EXIF => 'Y:m:d H:i:s', // This shouldn't ever be used, but is included for completeness
2481                 TS_RFC2822 => 'D, d M Y H:i:s',
2482                 TS_ORACLE => 'd-m-Y H:i:s.000000', // Was 'd-M-y h.i.s A' . ' +00:00' before r51500
2483                 TS_POSTGRES => 'Y-m-d H:i:s',
2484                 TS_DB2 => 'Y-m-d H:i:s',
2485         );
2486
2487         if ( !isset( $formats[$outputtype] ) ) {
2488                 throw new MWException( 'wfTimestamp() called with illegal output type.' );
2489         }
2490
2491         if ( function_exists( "date_create" ) ) {
2492                 if ( count( $da ) ) {
2493                         $ds = sprintf("%04d-%02d-%02dT%02d:%02d:%02d.00+00:00",
2494                                 (int)$da[1], (int)$da[2], (int)$da[3],
2495                                 (int)$da[4], (int)$da[5], (int)$da[6]);
2496
2497                         $d = date_create( $ds, new DateTimeZone( 'GMT' ) );
2498                 } elseif ( $strtime ) {
2499                         $d = date_create( $strtime, new DateTimeZone( 'GMT' ) );
2500                 } else {
2501                         return false;
2502                 }
2503
2504                 if ( !$d ) {
2505                         wfDebug("wfTimestamp() fed bogus time value: $outputtype; $ts\n");
2506                         return false;
2507                 }
2508
2509                 $output = $d->format( $formats[$outputtype] );
2510         } else {
2511                 if ( count( $da ) ) {
2512                         // Warning! gmmktime() acts oddly if the month or day is set to 0
2513                         // We may want to handle that explicitly at some point
2514                         $uts = gmmktime( (int)$da[4], (int)$da[5], (int)$da[6],
2515                                 (int)$da[2], (int)$da[3], (int)$da[1] );
2516                 } elseif ( $strtime ) {
2517                         $uts = strtotime( $strtime );
2518                 }
2519
2520                 if ( $uts === false ) {
2521                         wfDebug("wfTimestamp() can't parse the timestamp (non 32-bit time? Update php): $outputtype; $ts\n");
2522                         return false;
2523                 }
2524
2525                 if ( TS_UNIX == $outputtype ) {
2526                         return $uts;
2527                 }
2528                 $output = gmdate( $formats[$outputtype], $uts );
2529         }
2530
2531         if ( ( $outputtype == TS_RFC2822 ) || ( $outputtype == TS_POSTGRES ) ) {
2532                 $output .= ' GMT';
2533         }
2534
2535         return $output;
2536 }
2537
2538 /**
2539  * Return a formatted timestamp, or null if input is null.
2540  * For dealing with nullable timestamp columns in the database.
2541  *
2542  * @param $outputtype Integer
2543  * @param $ts String
2544  * @return String
2545  */
2546 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2547         if( is_null( $ts ) ) {
2548                 return null;
2549         } else {
2550                 return wfTimestamp( $outputtype, $ts );
2551         }
2552 }
2553
2554 /**
2555  * Convenience function; returns MediaWiki timestamp for the present time.
2556  *
2557  * @return string
2558  */
2559 function wfTimestampNow() {
2560         # return NOW
2561         return wfTimestamp( TS_MW, time() );
2562 }
2563
2564 /**
2565  * Check if the operating system is Windows
2566  *
2567  * @return Bool: true if it's Windows, False otherwise.
2568  */
2569 function wfIsWindows() {
2570         static $isWindows = null;
2571         if ( $isWindows === null ) {
2572                 $isWindows = substr( php_uname(), 0, 7 ) == 'Windows';
2573         }
2574         return $isWindows;
2575 }
2576
2577 /**
2578  * Check if we are running under HipHop
2579  *
2580  * @return Bool
2581  */
2582 function wfIsHipHop() {
2583         return function_exists( 'hphp_thread_set_warmup_enabled' );
2584 }
2585
2586 /**
2587  * Swap two variables
2588  *
2589  * @param $x Mixed
2590  * @param $y Mixed
2591  */
2592 function swap( &$x, &$y ) {
2593         $z = $x;
2594         $x = $y;
2595         $y = $z;
2596 }
2597
2598 /**
2599  * Tries to get the system directory for temporary files. The TMPDIR, TMP, and
2600  * TEMP environment variables are then checked in sequence, and if none are set
2601  * try sys_get_temp_dir() for PHP >= 5.2.1. All else fails, return /tmp for Unix
2602  * or C:\Windows\Temp for Windows and hope for the best.
2603  * It is common to call it with tempnam().
2604  *
2605  * NOTE: When possible, use instead the tmpfile() function to create
2606  * temporary files to avoid race conditions on file creation, etc.
2607  *
2608  * @return String
2609  */
2610 function wfTempDir() {
2611         foreach( array( 'TMPDIR', 'TMP', 'TEMP' ) as $var ) {
2612                 $tmp = getenv( $var );
2613                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
2614                         return $tmp;
2615                 }
2616         }
2617         if( function_exists( 'sys_get_temp_dir' ) ) {
2618                 return sys_get_temp_dir();
2619         }
2620         # Usual defaults
2621         return wfIsWindows() ? 'C:\Windows\Temp' : '/tmp';
2622 }
2623
2624 /**
2625  * Make directory, and make all parent directories if they don't exist
2626  *
2627  * @param $dir String: full path to directory to create
2628  * @param $mode Integer: chmod value to use, default is $wgDirectoryMode
2629  * @param $caller String: optional caller param for debugging.
2630  * @return bool
2631  */
2632 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2633         global $wgDirectoryMode;
2634
2635         if ( FileBackend::isStoragePath( $dir ) ) { // sanity
2636                 throw new MWException( __FUNCTION__ . " given storage path `$dir`.");
2637         }
2638
2639         if ( !is_null( $caller ) ) {
2640                 wfDebug( "$caller: called wfMkdirParents($dir)\n" );
2641         }
2642
2643         if( strval( $dir ) === '' || file_exists( $dir ) ) {
2644                 return true;
2645         }
2646
2647         $dir = str_replace( array( '\\', '/' ), DIRECTORY_SEPARATOR, $dir );
2648
2649         if ( is_null( $mode ) ) {
2650                 $mode = $wgDirectoryMode;
2651         }
2652
2653         // Turn off the normal warning, we're doing our own below
2654         wfSuppressWarnings();
2655         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2656         wfRestoreWarnings();
2657
2658         if( !$ok ) {
2659                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2660                 trigger_error( __FUNCTION__ . ": failed to mkdir \"$dir\" mode $mode", E_USER_WARNING );
2661         }
2662         return $ok;
2663 }
2664
2665 /**
2666  * Remove a directory and all its content.
2667  * Does not hide error.
2668  */
2669 function wfRecursiveRemoveDir( $dir ) {
2670         wfDebug( __FUNCTION__ . "( $dir )\n" );
2671         // taken from http://de3.php.net/manual/en/function.rmdir.php#98622
2672         if ( is_dir( $dir ) ) {
2673                 $objects = scandir( $dir );
2674                 foreach ( $objects as $object ) {
2675                         if ( $object != "." && $object != ".." ) {
2676                                 if ( filetype( $dir . '/' . $object ) == "dir" ) {
2677                                         wfRecursiveRemoveDir( $dir . '/' . $object );
2678                                 } else {
2679                                         unlink( $dir . '/' . $object );
2680                                 }
2681                         }
2682                 }
2683                 reset( $objects );
2684                 rmdir( $dir );
2685         }
2686 }
2687
2688 /**
2689  * @param $nr Mixed: the number to format
2690  * @param $acc Integer: the number of digits after the decimal point, default 2
2691  * @param $round Boolean: whether or not to round the value, default true
2692  * @return float
2693  */
2694 function wfPercent( $nr, $acc = 2, $round = true ) {
2695         $ret = sprintf( "%.${acc}f", $nr );
2696         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2697 }
2698
2699 /**
2700  * Find out whether or not a mixed variable exists in a string
2701  *
2702  * @param $needle String
2703  * @param $str String
2704  * @param $insensitive Boolean
2705  * @return Boolean
2706  */
2707 function in_string( $needle, $str, $insensitive = false ) {
2708         $func = 'strpos';
2709         if( $insensitive ) $func = 'stripos';
2710
2711         return $func( $str, $needle ) !== false;
2712 }
2713
2714 /**
2715  * Safety wrapper around ini_get() for boolean settings.
2716  * The values returned from ini_get() are pre-normalized for settings
2717  * set via php.ini or php_flag/php_admin_flag... but *not*
2718  * for those set via php_value/php_admin_value.
2719  *
2720  * It's fairly common for people to use php_value instead of php_flag,
2721  * which can leave you with an 'off' setting giving a false positive
2722  * for code that just takes the ini_get() return value as a boolean.
2723  *
2724  * To make things extra interesting, setting via php_value accepts
2725  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2726  * Unrecognized values go false... again opposite PHP's own coercion
2727  * from string to bool.
2728  *
2729  * Luckily, 'properly' set settings will always come back as '0' or '1',
2730  * so we only have to worry about them and the 'improper' settings.
2731  *
2732  * I frickin' hate PHP... :P
2733  *
2734  * @param $setting String
2735  * @return Bool
2736  */
2737 function wfIniGetBool( $setting ) {
2738         $val = ini_get( $setting );
2739         // 'on' and 'true' can't have whitespace around them, but '1' can.
2740         return strtolower( $val ) == 'on'
2741                 || strtolower( $val ) == 'true'
2742                 || strtolower( $val ) == 'yes'
2743                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2744 }
2745
2746 /**
2747  * Wrapper function for PHP's dl(). This doesn't work in most situations from
2748  * PHP 5.3 onward, and is usually disabled in shared environments anyway.
2749  *
2750  * @param $extension String A PHP extension. The file suffix (.so or .dll)
2751  *                          should be omitted
2752  * @param $fileName String Name of the library, if not $extension.suffix
2753  * @return Bool - Whether or not the extension is loaded
2754  */
2755 function wfDl( $extension, $fileName = null ) {
2756         if( extension_loaded( $extension ) ) {
2757                 return true;
2758         }
2759
2760         $canDl = false;
2761         $sapi = php_sapi_name();
2762         if( version_compare( PHP_VERSION, '5.3.0', '<' ) ||
2763                 $sapi == 'cli' || $sapi == 'cgi' || $sapi == 'embed' )
2764         {
2765                 $canDl = ( function_exists( 'dl' ) && is_callable( 'dl' )
2766                 && wfIniGetBool( 'enable_dl' ) && !wfIniGetBool( 'safe_mode' ) );
2767         }
2768
2769         if( $canDl ) {
2770                 $fileName = $fileName ? $fileName : $extension;
2771                 if( wfIsWindows() ) {
2772                         $fileName = 'php_' . $fileName;
2773                 }
2774                 wfSuppressWarnings();
2775                 dl( $fileName . '.' . PHP_SHLIB_SUFFIX );
2776                 wfRestoreWarnings();
2777         }
2778         return extension_loaded( $extension );
2779 }
2780
2781 /**
2782  * Windows-compatible version of escapeshellarg()
2783  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
2784  * function puts single quotes in regardless of OS.
2785  *
2786  * Also fixes the locale problems on Linux in PHP 5.2.6+ (bug backported to
2787  * earlier distro releases of PHP)
2788  *
2789  * @param varargs
2790  * @return String
2791  */
2792 function wfEscapeShellArg( ) {
2793         wfInitShellLocale();
2794
2795         $args = func_get_args();
2796         $first = true;
2797         $retVal = '';
2798         foreach ( $args as $arg ) {
2799                 if ( !$first ) {
2800                         $retVal .= ' ';
2801                 } else {
2802                         $first = false;
2803                 }
2804
2805                 if ( wfIsWindows() ) {
2806                         // Escaping for an MSVC-style command line parser and CMD.EXE
2807                         // Refs:
2808                         //  * http://web.archive.org/web/20020708081031/http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
2809                         //  * http://technet.microsoft.com/en-us/library/cc723564.aspx
2810                         //  * Bug #13518
2811                         //  * CR r63214
2812                         // Double the backslashes before any double quotes. Escape the double quotes.
2813                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
2814                         $arg = '';
2815                         $iteration = 0;
2816                         foreach ( $tokens as $token ) {
2817                                 if ( $iteration % 2 == 1 ) {
2818                                         // Delimiter, a double quote preceded by zero or more slashes
2819                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
2820                                 } elseif ( $iteration % 4 == 2 ) {
2821                                         // ^ in $token will be outside quotes, need to be escaped
2822                                         $arg .= str_replace( '^', '^^', $token );
2823                                 } else { // $iteration % 4 == 0
2824                                         // ^ in $token will appear inside double quotes, so leave as is
2825                                         $arg .= $token;
2826                                 }
2827                                 $iteration++;
2828                         }
2829                         // Double the backslashes before the end of the string, because
2830                         // we will soon add a quote
2831                         $m = array();
2832                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
2833                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
2834                         }
2835
2836                         // Add surrounding quotes
2837                         $retVal .= '"' . $arg . '"';
2838                 } else {
2839                         $retVal .= escapeshellarg( $arg );
2840                 }
2841         }
2842         return $retVal;
2843 }
2844
2845 /**
2846  * Execute a shell command, with time and memory limits mirrored from the PHP
2847  * configuration if supported.
2848  * @param $cmd String Command line, properly escaped for shell.
2849  * @param &$retval null|Mixed optional, will receive the program's exit code.
2850  *                 (non-zero is usually failure)
2851  * @param $environ Array optional environment variables which should be
2852  *                 added to the executed command environment.
2853  * @return string collected stdout as a string (trailing newlines stripped)
2854  */
2855 function wfShellExec( $cmd, &$retval = null, $environ = array() ) {
2856         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize, $wgMaxShellTime;
2857
2858         static $disabled;
2859         if ( is_null( $disabled ) ) {
2860                 $disabled = false;
2861                 if( wfIniGetBool( 'safe_mode' ) ) {
2862                         wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
2863                         $disabled = 'safemode';
2864                 } else {
2865                         $functions = explode( ',', ini_get( 'disable_functions' ) );
2866                         $functions = array_map( 'trim', $functions );
2867                         $functions = array_map( 'strtolower', $functions );
2868                         if ( in_array( 'passthru', $functions ) ) {
2869                                 wfDebug( "passthru is in disabled_functions\n" );
2870                                 $disabled = 'passthru';
2871                         }
2872                 }
2873         }
2874         if ( $disabled ) {
2875                 $retval = 1;
2876                 return $disabled == 'safemode' ?
2877                         'Unable to run external programs in safe mode.' :
2878                         'Unable to run external programs, passthru() is disabled.';
2879         }
2880
2881         wfInitShellLocale();
2882
2883         $envcmd = '';
2884         foreach( $environ as $k => $v ) {
2885                 if ( wfIsWindows() ) {
2886                         /* Surrounding a set in quotes (method used by wfEscapeShellArg) makes the quotes themselves
2887                          * appear in the environment variable, so we must use carat escaping as documented in
2888                          * http://technet.microsoft.com/en-us/library/cc723564.aspx
2889                          * Note however that the quote isn't listed there, but is needed, and the parentheses
2890                          * are listed there but doesn't appear to need it.
2891                          */
2892                         $envcmd .= "set $k=" . preg_replace( '/([&|()<>^"])/', '^\\1', $v ) . '&& ';
2893                 } else {
2894                         /* Assume this is a POSIX shell, thus required to accept variable assignments before the command
2895                          * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_09_01
2896                          */
2897                         $envcmd .= "$k=" . escapeshellarg( $v ) . ' ';
2898                 }
2899         }
2900         $cmd = $envcmd . $cmd;
2901
2902         if ( wfIsWindows() ) {
2903                 if ( version_compare( PHP_VERSION, '5.3.0', '<' ) && /* Fixed in 5.3.0 :) */
2904                         ( version_compare( PHP_VERSION, '5.2.1', '>=' ) || php_uname( 's' ) == 'Windows NT' ) )
2905                 {
2906                         # Hack to work around PHP's flawed invocation of cmd.exe
2907                         # http://news.php.net/php.internals/21796
2908                         # Windows 9x doesn't accept any kind of quotes
2909                         $cmd = '"' . $cmd . '"';
2910                 }
2911         } elseif ( php_uname( 's' ) == 'Linux' ) {
2912                 $time = intval( $wgMaxShellTime );
2913                 $mem = intval( $wgMaxShellMemory );
2914                 $filesize = intval( $wgMaxShellFileSize );
2915
2916                 if ( $time > 0 && $mem > 0 ) {
2917                         $script = "$IP/bin/ulimit4.sh";
2918                         if ( is_executable( $script ) ) {
2919                                 $cmd = '/bin/bash ' . escapeshellarg( $script ) . " $time $mem $filesize " . escapeshellarg( $cmd );
2920                         }
2921                 }
2922         }
2923         wfDebug( "wfShellExec: $cmd\n" );
2924
2925         $retval = 1; // error by default?
2926         ob_start();
2927         passthru( $cmd, $retval );
2928         $output = ob_get_contents();
2929         ob_end_clean();
2930
2931         if ( $retval == 127 ) {
2932                 wfDebugLog( 'exec', "Possibly missing executable file: $cmd\n" );
2933         }
2934         return $output;
2935 }
2936
2937 /**
2938  * Workaround for http://bugs.php.net/bug.php?id=45132
2939  * escapeshellarg() destroys non-ASCII characters if LANG is not a UTF-8 locale
2940  */
2941 function wfInitShellLocale() {
2942         static $done = false;
2943         if ( $done ) {
2944                 return;
2945         }
2946         $done = true;
2947         global $wgShellLocale;
2948         if ( !wfIniGetBool( 'safe_mode' ) ) {
2949                 putenv( "LC_CTYPE=$wgShellLocale" );
2950                 setlocale( LC_CTYPE, $wgShellLocale );
2951         }
2952 }
2953
2954 /**
2955  * Alias to wfShellWikiCmd()
2956  * @see wfShellWikiCmd()
2957  */
2958 function wfShellMaintenanceCmd( $script, array $parameters = array(), array $options = array() ) {
2959         return wfShellWikiCmd( $script, $parameters, $options );
2960 }
2961
2962 /**
2963  * Generate a shell-escaped command line string to run a MediaWiki cli script.
2964  * Note that $parameters should be a flat array and an option with an argument
2965  * should consist of two consecutive items in the array (do not use "--option value").
2966  * @param $script string MediaWiki cli script path
2967  * @param $parameters Array Arguments and options to the script
2968  * @param $options Array Associative array of options:
2969  *              'php': The path to the php executable
2970  *              'wrapper': Path to a PHP wrapper to handle the maintenance script
2971  * @return Array
2972  */
2973 function wfShellWikiCmd( $script, array $parameters = array(), array $options = array() ) {
2974         global $wgPhpCli;
2975         // Give site config file a chance to run the script in a wrapper.
2976         // The caller may likely want to call wfBasename() on $script.
2977         wfRunHooks( 'wfShellWikiCmd', array( &$script, &$parameters, &$options ) );
2978         $cmd = isset( $options['php'] ) ? array( $options['php'] ) : array( $wgPhpCli );
2979         if ( isset( $options['wrapper'] ) ) {
2980                 $cmd[] = $options['wrapper'];
2981         }
2982         $cmd[] = $script;
2983         // Escape each parameter for shell
2984         return implode( " ", array_map( 'wfEscapeShellArg', array_merge( $cmd, $parameters ) ) );
2985 }
2986
2987 /**
2988  * wfMerge attempts to merge differences between three texts.
2989  * Returns true for a clean merge and false for failure or a conflict.
2990  *
2991  * @param $old String
2992  * @param $mine String
2993  * @param $yours String
2994  * @param $result String
2995  * @return Bool
2996  */
2997 function wfMerge( $old, $mine, $yours, &$result ) {
2998         global $wgDiff3;
2999
3000         # This check may also protect against code injection in
3001         # case of broken installations.
3002         wfSuppressWarnings();
3003         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
3004         wfRestoreWarnings();
3005
3006         if( !$haveDiff3 ) {
3007                 wfDebug( "diff3 not found\n" );
3008                 return false;
3009         }
3010
3011         # Make temporary files
3012         $td = wfTempDir();
3013         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
3014         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
3015         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
3016
3017         fwrite( $oldtextFile, $old );
3018         fclose( $oldtextFile );
3019         fwrite( $mytextFile, $mine );
3020         fclose( $mytextFile );
3021         fwrite( $yourtextFile, $yours );
3022         fclose( $yourtextFile );
3023
3024         # Check for a conflict
3025         $cmd = $wgDiff3 . ' -a --overlap-only ' .
3026                 wfEscapeShellArg( $mytextName ) . ' ' .
3027                 wfEscapeShellArg( $oldtextName ) . ' ' .
3028                 wfEscapeShellArg( $yourtextName );
3029         $handle = popen( $cmd, 'r' );
3030
3031         if( fgets( $handle, 1024 ) ) {
3032                 $conflict = true;
3033         } else {
3034                 $conflict = false;
3035         }
3036         pclose( $handle );
3037
3038         # Merge differences
3039         $cmd = $wgDiff3 . ' -a -e --merge ' .
3040                 wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
3041         $handle = popen( $cmd, 'r' );
3042         $result = '';
3043         do {
3044                 $data = fread( $handle, 8192 );
3045                 if ( strlen( $data ) == 0 ) {
3046                         break;
3047                 }
3048                 $result .= $data;
3049         } while ( true );
3050         pclose( $handle );
3051         unlink( $mytextName );
3052         unlink( $oldtextName );
3053         unlink( $yourtextName );
3054
3055         if ( $result === '' && $old !== '' && !$conflict ) {
3056                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
3057                 $conflict = true;
3058         }
3059         return !$conflict;
3060 }
3061
3062 /**
3063  * Returns unified plain-text diff of two texts.
3064  * Useful for machine processing of diffs.
3065  *
3066  * @param $before String: the text before the changes.
3067  * @param $after String: the text after the changes.
3068  * @param $params String: command-line options for the diff command.
3069  * @return String: unified diff of $before and $after
3070  */
3071 function wfDiff( $before, $after, $params = '-u' ) {
3072         if ( $before == $after ) {
3073                 return '';
3074         }
3075
3076         global $wgDiff;
3077         wfSuppressWarnings();
3078         $haveDiff = $wgDiff && file_exists( $wgDiff );
3079         wfRestoreWarnings();
3080
3081         # This check may also protect against code injection in
3082         # case of broken installations.
3083         if( !$haveDiff ) {
3084                 wfDebug( "diff executable not found\n" );
3085                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
3086                 $format = new UnifiedDiffFormatter();
3087                 return $format->format( $diffs );
3088         }
3089
3090         # Make temporary files
3091         $td = wfTempDir();
3092         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
3093         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
3094
3095         fwrite( $oldtextFile, $before );
3096         fclose( $oldtextFile );
3097         fwrite( $newtextFile, $after );
3098         fclose( $newtextFile );
3099
3100         // Get the diff of the two files
3101         $cmd = "$wgDiff " . $params . ' ' . wfEscapeShellArg( $oldtextName, $newtextName );
3102
3103         $h = popen( $cmd, 'r' );
3104
3105         $diff = '';
3106
3107         do {
3108                 $data = fread( $h, 8192 );
3109                 if ( strlen( $data ) == 0 ) {
3110                         break;
3111                 }
3112                 $diff .= $data;
3113         } while ( true );
3114
3115         // Clean up
3116         pclose( $h );
3117         unlink( $oldtextName );
3118         unlink( $newtextName );
3119
3120         // Kill the --- and +++ lines. They're not useful.
3121         $diff_lines = explode( "\n", $diff );
3122         if ( strpos( $diff_lines[0], '---' ) === 0 ) {
3123                 unset( $diff_lines[0] );
3124         }
3125         if ( strpos( $diff_lines[1], '+++' ) === 0 ) {
3126                 unset( $diff_lines[1] );
3127         }
3128
3129         $diff = implode( "\n", $diff_lines );
3130
3131         return $diff;
3132 }
3133
3134 /**
3135  * This function works like "use VERSION" in Perl, the program will die with a
3136  * backtrace if the current version of PHP is less than the version provided
3137  *
3138  * This is useful for extensions which due to their nature are not kept in sync
3139  * with releases, and might depend on other versions of PHP than the main code
3140  *
3141  * Note: PHP might die due to parsing errors in some cases before it ever
3142  *       manages to call this function, such is life
3143  *
3144  * @see perldoc -f use
3145  *
3146  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
3147  *                 a float
3148  */
3149 function wfUsePHP( $req_ver ) {
3150         $php_ver = PHP_VERSION;
3151
3152         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
3153                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
3154         }
3155 }
3156
3157 /**
3158  * This function works like "use VERSION" in Perl except it checks the version
3159  * of MediaWiki, the program will die with a backtrace if the current version
3160  * of MediaWiki is less than the version provided.
3161  *
3162  * This is useful for extensions which due to their nature are not kept in sync
3163  * with releases
3164  *
3165  * @see perldoc -f use
3166  *
3167  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
3168  *                 a float
3169  */
3170 function wfUseMW( $req_ver ) {
3171         global $wgVersion;
3172
3173         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
3174                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
3175         }
3176 }
3177
3178 /**
3179  * Return the final portion of a pathname.
3180  * Reimplemented because PHP5's basename() is buggy with multibyte text.
3181  * http://bugs.php.net/bug.php?id=33898
3182  *
3183  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
3184  * We'll consider it so always, as we don't want \s in our Unix paths either.
3185  *
3186  * @param $path String
3187  * @param $suffix String: to remove if present
3188  * @return String
3189  */
3190 function wfBaseName( $path, $suffix = '' ) {
3191         $encSuffix = ( $suffix == '' )
3192                 ? ''
3193                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
3194         $matches = array();
3195         if( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
3196                 return $matches[1];
3197         } else {
3198                 return '';
3199         }
3200 }
3201
3202 /**
3203  * Generate a relative path name to the given file.
3204  * May explode on non-matching case-insensitive paths,
3205  * funky symlinks, etc.
3206  *
3207  * @param $path String: absolute destination path including target filename
3208  * @param $from String: Absolute source path, directory only
3209  * @return String
3210  */
3211 function wfRelativePath( $path, $from ) {
3212         // Normalize mixed input on Windows...
3213         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
3214         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
3215
3216         // Trim trailing slashes -- fix for drive root
3217         $path = rtrim( $path, DIRECTORY_SEPARATOR );
3218         $from = rtrim( $from, DIRECTORY_SEPARATOR );
3219
3220         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
3221         $against = explode( DIRECTORY_SEPARATOR, $from );
3222
3223         if( $pieces[0] !== $against[0] ) {
3224                 // Non-matching Windows drive letters?
3225                 // Return a full path.
3226                 return $path;
3227         }
3228
3229         // Trim off common prefix
3230         while( count( $pieces ) && count( $against )
3231                 && $pieces[0] == $against[0] ) {
3232                 array_shift( $pieces );
3233                 array_shift( $against );
3234         }
3235
3236         // relative dots to bump us to the parent
3237         while( count( $against ) ) {
3238                 array_unshift( $pieces, '..' );
3239                 array_shift( $against );
3240         }
3241
3242         array_push( $pieces, wfBaseName( $path ) );
3243
3244         return implode( DIRECTORY_SEPARATOR, $pieces );
3245 }
3246
3247 /**
3248  * Do any deferred updates and clear the list
3249  *
3250  * @deprecated since 1.19
3251  * @see DeferredUpdates::doUpdate()
3252  * @param $commit string
3253  */
3254 function wfDoUpdates( $commit = '' ) {
3255         wfDeprecated( __METHOD__, '1.19' );
3256         DeferredUpdates::doUpdates( $commit );
3257 }
3258
3259 /**
3260  * Convert an arbitrarily-long digit string from one numeric base
3261  * to another, optionally zero-padding to a minimum column width.
3262  *
3263  * Supports base 2 through 36; digit values 10-36 are represented
3264  * as lowercase letters a-z. Input is case-insensitive.
3265  *
3266  * @param $input String: of digits
3267  * @param $sourceBase Integer: 2-36
3268  * @param $destBase Integer: 2-36
3269  * @param $pad Integer: 1 or greater
3270  * @param $lowercase Boolean
3271  * @return String or false on invalid input
3272  */
3273 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1, $lowercase = true ) {
3274         $input = strval( $input );
3275         if( $sourceBase < 2 ||
3276                 $sourceBase > 36 ||
3277                 $destBase < 2 ||
3278                 $destBase > 36 ||
3279                 $pad < 1 ||
3280                 $sourceBase != intval( $sourceBase ) ||
3281                 $destBase != intval( $destBase ) ||
3282                 $pad != intval( $pad ) ||
3283                 !is_string( $input ) ||
3284                 $input == '' ) {
3285                 return false;
3286         }
3287         $digitChars = ( $lowercase ) ? '0123456789abcdefghijklmnopqrstuvwxyz' : '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
3288         $inDigits = array();
3289         $outChars = '';
3290
3291         // Decode and validate input string
3292         $input = strtolower( $input );
3293         for( $i = 0; $i < strlen( $input ); $i++ ) {
3294                 $n = strpos( $digitChars, $input[$i] );
3295                 if( $n === false || $n > $sourceBase ) {
3296                         return false;
3297                 }
3298                 $inDigits[] = $n;
3299         }
3300
3301         // Iterate over the input, modulo-ing out an output digit
3302         // at a time until input is gone.
3303         while( count( $inDigits ) ) {
3304                 $work = 0;
3305                 $workDigits = array();
3306
3307                 // Long division...
3308                 foreach( $inDigits as $digit ) {
3309                         $work *= $sourceBase;
3310                         $work += $digit;
3311
3312                         if( $work < $destBase ) {
3313                                 // Gonna need to pull another digit.
3314                                 if( count( $workDigits ) ) {
3315                                         // Avoid zero-padding; this lets us find
3316                                         // the end of the input very easily when
3317                                         // length drops to zero.
3318                                         $workDigits[] = 0;
3319                                 }
3320                         } else {
3321                                 // Finally! Actual division!
3322                                 $workDigits[] = intval( $work / $destBase );
3323
3324                                 // Isn't it annoying that most programming languages
3325                                 // don't have a single divide-and-remainder operator,
3326                                 // even though the CPU implements it that way?
3327                                 $work = $work % $destBase;
3328                         }
3329                 }
3330
3331                 // All that division leaves us with a remainder,
3332                 // which is conveniently our next output digit.
3333                 $outChars .= $digitChars[$work];
3334
3335                 // And we continue!
3336                 $inDigits = $workDigits;
3337         }
3338
3339         while( strlen( $outChars ) < $pad ) {
3340                 $outChars .= '0';
3341         }
3342
3343         return strrev( $outChars );
3344 }
3345
3346 /**
3347  * Create an object with a given name and an array of construct parameters
3348  *
3349  * @param $name String
3350  * @param $p Array: parameters
3351  * @return object
3352  * @deprecated since 1.18, warnings in 1.18, removal in 1.20
3353  */
3354 function wfCreateObject( $name, $p ) {
3355         wfDeprecated( __FUNCTION__, '1.18' );
3356         return MWFunction::newObj( $name, $p );
3357 }
3358
3359 /**
3360  * @return bool
3361  */
3362 function wfHttpOnlySafe() {
3363         global $wgHttpOnlyBlacklist;
3364
3365         if( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
3366                 foreach( $wgHttpOnlyBlacklist as $regex ) {
3367                         if( preg_match( $regex, $_SERVER['HTTP_USER_AGENT'] ) ) {
3368                                 return false;
3369                         }
3370                 }
3371         }
3372
3373         return true;
3374 }
3375
3376 /**
3377  * Override session_id before session startup if php's built-in
3378  * session generation code is not secure.
3379  */
3380 function wfFixSessionID() {
3381         // If the cookie or session id is already set we already have a session and should abort
3382         if ( isset( $_COOKIE[ session_name() ] ) || session_id() ) {
3383                 return;
3384         }
3385
3386         // PHP's built-in session entropy is enabled if:
3387         // - entropy_file is set or you're on Windows with php 5.3.3+
3388         // - AND entropy_length is > 0
3389         // We treat it as disabled if it doesn't have an entropy length of at least 32
3390         $entropyEnabled = (
3391                         ( wfIsWindows() && version_compare( PHP_VERSION, '5.3.3', '>=' ) )
3392                         || ini_get( 'session.entropy_file' )
3393                 )
3394                 && intval( ini_get( 'session.entropy_length' ) ) >= 32;
3395
3396         // If built-in entropy is not enabled or not sufficient override php's built in session id generation code
3397         if ( !$entropyEnabled ) {
3398                 wfDebug( __METHOD__ . ": PHP's built in entropy is disabled or not sufficient, overriding session id generation using our cryptrand source.\n" );
3399                 session_id( MWCryptRand::generateHex( 32 ) );
3400         }
3401 }
3402
3403 /**
3404  * Initialise php session
3405  *
3406  * @param $sessionId Bool
3407  */
3408 function wfSetupSession( $sessionId = false ) {
3409         global $wgSessionsInMemcached, $wgCookiePath, $wgCookieDomain,
3410                         $wgCookieSecure, $wgCookieHttpOnly, $wgSessionHandler;
3411         if( $wgSessionsInMemcached ) {
3412                 if ( !defined( 'MW_COMPILED' ) ) {
3413                         global $IP;
3414                         require_once( "$IP/includes/cache/MemcachedSessions.php" );
3415                 }
3416                 session_set_save_handler( 'memsess_open', 'memsess_close', 'memsess_read',
3417                         'memsess_write', 'memsess_destroy', 'memsess_gc' );
3418
3419                 // It's necessary to register a shutdown function to call session_write_close(),
3420                 // because by the time the request shutdown function for the session module is
3421                 // called, $wgMemc has already been destroyed. Shutdown functions registered
3422                 // this way are called before object destruction.
3423                 register_shutdown_function( 'memsess_write_close' );
3424         } elseif( $wgSessionHandler && $wgSessionHandler != ini_get( 'session.save_handler' ) ) {
3425                 # Only set this if $wgSessionHandler isn't null and session.save_handler
3426                 # hasn't already been set to the desired value (that causes errors)
3427                 ini_set( 'session.save_handler', $wgSessionHandler );
3428         }
3429         $httpOnlySafe = wfHttpOnlySafe() && $wgCookieHttpOnly;
3430         wfDebugLog( 'cookie',
3431                 'session_set_cookie_params: "' . implode( '", "',
3432                         array(
3433                                 0,
3434                                 $wgCookiePath,
3435                                 $wgCookieDomain,
3436                                 $wgCookieSecure,
3437                                 $httpOnlySafe ) ) . '"' );
3438         session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $httpOnlySafe );
3439         session_cache_limiter( 'private, must-revalidate' );
3440         if ( $sessionId ) {
3441                 session_id( $sessionId );
3442         } else {
3443                 wfFixSessionID();
3444         }
3445         wfSuppressWarnings();
3446         session_start();
3447         wfRestoreWarnings();
3448 }
3449
3450 /**
3451  * Get an object from the precompiled serialized directory
3452  *
3453  * @param $name String
3454  * @return Mixed: the variable on success, false on failure
3455  */
3456 function wfGetPrecompiledData( $name ) {
3457         global $IP;
3458
3459         $file = "$IP/serialized/$name";
3460         if ( file_exists( $file ) ) {
3461                 $blob = file_get_contents( $file );
3462                 if ( $blob ) {
3463                         return unserialize( $blob );
3464                 }
3465         }
3466         return false;
3467 }
3468
3469 /**
3470  * Get a cache key
3471  *
3472  * @param varargs
3473  * @return String
3474  */
3475 function wfMemcKey( /*... */ ) {
3476         global $wgCachePrefix;
3477         $prefix = $wgCachePrefix === false ? wfWikiID() : $wgCachePrefix;
3478         $args = func_get_args();
3479         $key = $prefix . ':' . implode( ':', $args );
3480         $key = str_replace( ' ', '_', $key );
3481         return $key;
3482 }
3483
3484 /**
3485  * Get a cache key for a foreign DB
3486  *
3487  * @param $db String
3488  * @param $prefix String
3489  * @param varargs String
3490  * @return String
3491  */
3492 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
3493         $args = array_slice( func_get_args(), 2 );
3494         if ( $prefix ) {
3495                 $key = "$db-$prefix:" . implode( ':', $args );
3496         } else {
3497                 $key = $db . ':' . implode( ':', $args );
3498         }
3499         return $key;
3500 }
3501
3502 /**
3503  * Get an ASCII string identifying this wiki
3504  * This is used as a prefix in memcached keys
3505  *
3506  * @return String
3507  */
3508 function wfWikiID() {
3509         global $wgDBprefix, $wgDBname;
3510         if ( $wgDBprefix ) {
3511                 return "$wgDBname-$wgDBprefix";
3512         } else {
3513                 return $wgDBname;
3514         }
3515 }
3516
3517 /**
3518  * Split a wiki ID into DB name and table prefix
3519  *
3520  * @param $wiki String
3521  *
3522  * @return array
3523  */
3524 function wfSplitWikiID( $wiki ) {
3525         $bits = explode( '-', $wiki, 2 );
3526         if ( count( $bits ) < 2 ) {
3527                 $bits[] = '';
3528         }
3529         return $bits;
3530 }
3531
3532 /**
3533  * Get a Database object.
3534  *
3535  * @param $db Integer: index of the connection to get. May be DB_MASTER for the
3536  *            master (for write queries), DB_SLAVE for potentially lagged read
3537  *            queries, or an integer >= 0 for a particular server.
3538  *
3539  * @param $groups Mixed: query groups. An array of group names that this query
3540  *                belongs to. May contain a single string if the query is only
3541  *                in one group.
3542  *
3543  * @param $wiki String: the wiki ID, or false for the current wiki
3544  *
3545  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
3546  * will always return the same object, unless the underlying connection or load
3547  * balancer is manually destroyed.
3548  *
3549  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
3550  * updater to ensure that a proper database is being updated.
3551  *
3552  * @return DatabaseBase
3553  */
3554 function &wfGetDB( $db, $groups = array(), $wiki = false ) {
3555         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
3556 }
3557
3558 /**
3559  * Get a load balancer object.
3560  *
3561  * @param $wiki String: wiki ID, or false for the current wiki
3562  * @return LoadBalancer
3563  */
3564 function wfGetLB( $wiki = false ) {
3565         return wfGetLBFactory()->getMainLB( $wiki );
3566 }
3567
3568 /**
3569  * Get the load balancer factory object
3570  *
3571  * @return LBFactory
3572  */
3573 function &wfGetLBFactory() {
3574         return LBFactory::singleton();
3575 }
3576
3577 /**
3578  * Find a file.
3579  * Shortcut for RepoGroup::singleton()->findFile()
3580  *
3581  * @param $title String or Title object
3582  * @param $options array Associative array of options:
3583  *     time:           requested time for an archived image, or false for the
3584  *                     current version. An image object will be returned which was
3585  *                     created at the specified time.
3586  *
3587  *     ignoreRedirect: If true, do not follow file redirects
3588  *
3589  *     private:        If true, return restricted (deleted) files if the current
3590  *                     user is allowed to view them. Otherwise, such files will not
3591  *                     be found.
3592  *
3593  *     bypassCache:    If true, do not use the process-local cache of File objects
3594  *
3595  * @return File, or false if the file does not exist
3596  */
3597 function wfFindFile( $title, $options = array() ) {
3598         return RepoGroup::singleton()->findFile( $title, $options );
3599 }
3600
3601 /**
3602  * Get an object referring to a locally registered file.
3603  * Returns a valid placeholder object if the file does not exist.
3604  *
3605  * @param $title Title|String
3606  * @return File|null A File, or null if passed an invalid Title
3607  */
3608 function wfLocalFile( $title ) {
3609         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
3610 }
3611
3612 /**
3613  * Stream a file to the browser. Back-compat alias for StreamFile::stream()
3614  * @deprecated since 1.19
3615  */
3616 function wfStreamFile( $fname, $headers = array() ) {
3617         wfDeprecated( __FUNCTION__, '1.19' );
3618         StreamFile::stream( $fname, $headers );
3619 }
3620
3621 /**
3622  * Should low-performance queries be disabled?
3623  *
3624  * @return Boolean
3625  * @codeCoverageIgnore
3626  */
3627 function wfQueriesMustScale() {
3628         global $wgMiserMode;
3629         return $wgMiserMode
3630                 || ( SiteStats::pages() > 100000
3631                 && SiteStats::edits() > 1000000
3632                 && SiteStats::users() > 10000 );
3633 }
3634
3635 /**
3636  * Get the path to a specified script file, respecting file
3637  * extensions; this is a wrapper around $wgScriptExtension etc.
3638  *
3639  * @param $script String: script filename, sans extension
3640  * @return String
3641  */
3642 function wfScript( $script = 'index' ) {
3643         global $wgScriptPath, $wgScriptExtension;
3644         return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
3645 }
3646
3647 /**
3648  * Get the script URL.
3649  *
3650  * @return string script URL
3651  */
3652 function wfGetScriptUrl() {
3653         if( isset( $_SERVER['SCRIPT_NAME'] ) ) {
3654                 #
3655                 # as it was called, minus the query string.
3656                 #
3657                 # Some sites use Apache rewrite rules to handle subdomains,
3658                 # and have PHP set up in a weird way that causes PHP_SELF
3659                 # to contain the rewritten URL instead of the one that the
3660                 # outside world sees.
3661                 #
3662                 # If in this mode, use SCRIPT_URL instead, which mod_rewrite
3663                 # provides containing the "before" URL.
3664                 return $_SERVER['SCRIPT_NAME'];
3665         } else {
3666                 return $_SERVER['URL'];
3667         }
3668 }
3669
3670 /**
3671  * Convenience function converts boolean values into "true"
3672  * or "false" (string) values
3673  *
3674  * @param $value Boolean
3675  * @return String
3676  */
3677 function wfBoolToStr( $value ) {
3678         return $value ? 'true' : 'false';
3679 }
3680
3681 /**
3682  * Load an extension messages file
3683  *
3684  * @deprecated since 1.16, warnings in 1.18, remove in 1.20
3685  * @codeCoverageIgnore
3686  */
3687 function wfLoadExtensionMessages() {
3688         wfDeprecated( __FUNCTION__, '1.16' );
3689 }
3690
3691 /**
3692  * Get a platform-independent path to the null file, e.g. /dev/null
3693  *
3694  * @return string
3695  */
3696 function wfGetNull() {
3697         return wfIsWindows()
3698                 ? 'NUL'
3699                 : '/dev/null';
3700 }
3701
3702 /**
3703  * Modern version of wfWaitForSlaves(). Instead of looking at replication lag
3704  * and waiting for it to go down, this waits for the slaves to catch up to the
3705  * master position. Use this when updating very large numbers of rows, as
3706  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
3707  * a no-op if there are no slaves.
3708  *
3709  * @param $maxLag Integer (deprecated)
3710  * @param $wiki mixed Wiki identifier accepted by wfGetLB
3711  */
3712 function wfWaitForSlaves( $maxLag = false, $wiki = false ) {
3713         $lb = wfGetLB( $wiki );
3714         // bug 27975 - Don't try to wait for slaves if there are none
3715         // Prevents permission error when getting master position
3716         if ( $lb->getServerCount() > 1 ) {
3717                 $dbw = $lb->getConnection( DB_MASTER );
3718                 $pos = $dbw->getMasterPos();
3719                 $lb->waitForAll( $pos );
3720         }
3721 }
3722
3723 /**
3724  * Used to be used for outputting text in the installer/updater
3725  * @deprecated since 1.18, warnings in 1.18, remove in 1.20
3726  */
3727 function wfOut( $s ) {
3728         wfDeprecated( __FUNCTION__, '1.18' );
3729         global $wgCommandLineMode;
3730         if ( $wgCommandLineMode ) {
3731                 echo $s;
3732         } else {
3733                 echo htmlspecialchars( $s );
3734         }
3735         flush();
3736 }
3737
3738 /**
3739  * Count down from $n to zero on the terminal, with a one-second pause
3740  * between showing each number. For use in command-line scripts.
3741  * @codeCoverageIgnore
3742  * @param $n int
3743  */
3744 function wfCountDown( $n ) {
3745         for ( $i = $n; $i >= 0; $i-- ) {
3746                 if ( $i != $n ) {
3747                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3748                 }
3749                 echo $i;
3750                 flush();
3751                 if ( $i ) {
3752                         sleep( 1 );
3753                 }
3754         }
3755         echo "\n";
3756 }
3757
3758 /**
3759  * Generate a random 32-character hexadecimal token.
3760  * @param $salt Mixed: some sort of salt, if necessary, to add to random
3761  *              characters before hashing.
3762  * @return string
3763  * @codeCoverageIgnore
3764  * @deprecated since 1.20; Please use MWCryptRand for security purposes and wfRandomString for pesudo-random strings
3765  * @warning This method is NOT secure. Additionally it has many callers that use it for pesudo-random purposes.
3766  */
3767 function wfGenerateToken( $salt = '' ) {
3768         wfDeprecated( __METHOD__, '1.20' );
3769         $salt = serialize( $salt );
3770         return md5( mt_rand( 0, 0x7fffffff ) . $salt );
3771 }
3772
3773 /**
3774  * Replace all invalid characters with -
3775  *
3776  * @param $name Mixed: filename to process
3777  * @return String
3778  */
3779 function wfStripIllegalFilenameChars( $name ) {
3780         global $wgIllegalFileChars;
3781         $name = wfBaseName( $name );
3782         $name = preg_replace(
3783                 "/[^" . Title::legalChars() . "]" .
3784                         ( $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '' ) .
3785                         "/",
3786                 '-',
3787                 $name
3788         );
3789         return $name;
3790 }
3791
3792 /**
3793  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit;
3794  *
3795  * @return Integer value memory was set to.
3796  */
3797 function wfMemoryLimit() {
3798         global $wgMemoryLimit;
3799         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3800         if( $memlimit != -1 ) {
3801                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3802                 if( $conflimit == -1 ) {
3803                         wfDebug( "Removing PHP's memory limit\n" );
3804                         wfSuppressWarnings();
3805                         ini_set( 'memory_limit', $conflimit );
3806                         wfRestoreWarnings();
3807                         return $conflimit;
3808                 } elseif ( $conflimit > $memlimit ) {
3809                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3810                         wfSuppressWarnings();
3811                         ini_set( 'memory_limit', $conflimit );
3812                         wfRestoreWarnings();
3813                         return $conflimit;
3814                 }
3815         }
3816         return $memlimit;
3817 }
3818
3819 /**
3820  * Converts shorthand byte notation to integer form
3821  *
3822  * @param $string String
3823  * @return Integer
3824  */
3825 function wfShorthandToInteger( $string = '' ) {
3826         $string = trim( $string );
3827         if( $string === '' ) {
3828                 return -1;
3829         }
3830         $last = $string[strlen( $string ) - 1];
3831         $val = intval( $string );
3832         switch( $last ) {
3833                 case 'g':
3834                 case 'G':
3835                         $val *= 1024;
3836                         // break intentionally missing
3837                 case 'm':
3838                 case 'M':
3839                         $val *= 1024;
3840                         // break intentionally missing
3841                 case 'k':
3842                 case 'K':
3843                         $val *= 1024;
3844         }
3845
3846         return $val;
3847 }
3848
3849 /**
3850  * Get the normalised IETF language tag
3851  * See unit test for examples.
3852  *
3853  * @param $code String: The language code.
3854  * @return String: The language code which complying with BCP 47 standards.
3855  */
3856 function wfBCP47( $code ) {
3857         $codeSegment = explode( '-', $code );
3858         $codeBCP = array();
3859         foreach ( $codeSegment as $segNo => $seg ) {
3860                 if ( count( $codeSegment ) > 0 ) {
3861                         // when previous segment is x, it is a private segment and should be lc
3862                         if( $segNo > 0 && strtolower( $codeSegment[( $segNo - 1 )] ) == 'x' ) {
3863                                 $codeBCP[$segNo] = strtolower( $seg );
3864                         // ISO 3166 country code
3865                         } elseif ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3866                                 $codeBCP[$segNo] = strtoupper( $seg );
3867                         // ISO 15924 script code
3868                         } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3869                                 $codeBCP[$segNo] = ucfirst( strtolower( $seg ) );
3870                         // Use lowercase for other cases
3871                         } else {
3872                                 $codeBCP[$segNo] = strtolower( $seg );
3873                         }
3874                 } else {
3875                 // Use lowercase for single segment
3876                         $codeBCP[$segNo] = strtolower( $seg );
3877                 }
3878         }
3879         $langCode = implode( '-', $codeBCP );
3880         return $langCode;
3881 }
3882
3883 /**
3884  * Get a cache object.
3885  *
3886  * @param $inputType integer Cache type, one the the CACHE_* constants.
3887  * @return BagOStuff
3888  */
3889 function wfGetCache( $inputType ) {
3890         return ObjectCache::getInstance( $inputType );
3891 }
3892
3893 /**
3894  * Get the main cache object
3895  *
3896  * @return BagOStuff
3897  */
3898 function wfGetMainCache() {
3899         global $wgMainCacheType;
3900         return ObjectCache::getInstance( $wgMainCacheType );
3901 }
3902
3903 /**
3904  * Get the cache object used by the message cache
3905  *
3906  * @return BagOStuff
3907  */
3908 function wfGetMessageCacheStorage() {
3909         global $wgMessageCacheType;
3910         return ObjectCache::getInstance( $wgMessageCacheType );
3911 }
3912
3913 /**
3914  * Get the cache object used by the parser cache
3915  *
3916  * @return BagOStuff
3917  */
3918 function wfGetParserCacheStorage() {
3919         global $wgParserCacheType;
3920         return ObjectCache::getInstance( $wgParserCacheType );
3921 }
3922
3923 /**
3924  * Call hook functions defined in $wgHooks
3925  *
3926  * @param $event String: event name
3927  * @param $args Array: parameters passed to hook functions
3928  * @return Boolean True if no handler aborted the hook
3929  */
3930 function wfRunHooks( $event, $args = array() ) {
3931         return Hooks::run( $event, $args );
3932 }
3933
3934 /**
3935  * Wrapper around php's unpack.
3936  *
3937  * @param $format String: The format string (See php's docs)
3938  * @param $data: A binary string of binary data
3939  * @param $length integer or false: The minimun length of $data. This is to
3940  *      prevent reading beyond the end of $data. false to disable the check.
3941  *
3942  * Also be careful when using this function to read unsigned 32 bit integer
3943  * because php might make it negative.
3944  *
3945  * @throws MWException if $data not long enough, or if unpack fails
3946  * @return array Associative array of the extracted data
3947  */
3948 function wfUnpack( $format, $data, $length=false ) {
3949         if ( $length !== false ) {
3950                 $realLen = strlen( $data );
3951                 if ( $realLen < $length ) {
3952                         throw new MWException( "Tried to use wfUnpack on a "
3953                                 . "string of length $realLen, but needed one "
3954                                 . "of at least length $length."
3955                         );
3956                 }
3957         }
3958
3959         wfSuppressWarnings();
3960         $result = unpack( $format, $data );
3961         wfRestoreWarnings();
3962
3963         if ( $result === false ) {
3964                 // If it cannot extract the packed data.
3965                 throw new MWException( "unpack could not unpack binary data" );
3966         }
3967         return $result;
3968 }
3969
3970 /**
3971  * Determine if an image exists on the 'bad image list'.
3972  *
3973  * The format of MediaWiki:Bad_image_list is as follows:
3974  *    * Only list items (lines starting with "*") are considered
3975  *    * The first link on a line must be a link to a bad image
3976  *    * Any subsequent links on the same line are considered to be exceptions,
3977  *      i.e. articles where the image may occur inline.
3978  *
3979  * @param $name string the image name to check
3980  * @param $contextTitle Title|bool the page on which the image occurs, if known
3981  * @param $blacklist string wikitext of a file blacklist
3982  * @return bool
3983  */
3984 function wfIsBadImage( $name, $contextTitle = false, $blacklist = null ) {
3985         static $badImageCache = null; // based on bad_image_list msg
3986         wfProfileIn( __METHOD__ );
3987
3988         # Handle redirects
3989         $redirectTitle = RepoGroup::singleton()->checkRedirect( Title::makeTitle( NS_FILE, $name ) );
3990         if( $redirectTitle ) {
3991                 $name = $redirectTitle->getDbKey();
3992         }
3993
3994         # Run the extension hook
3995         $bad = false;
3996         if( !wfRunHooks( 'BadImage', array( $name, &$bad ) ) ) {
3997                 wfProfileOut( __METHOD__ );
3998                 return $bad;
3999         }
4000
4001         $cacheable = ( $blacklist === null );
4002         if( $cacheable && $badImageCache !== null ) {
4003                 $badImages = $badImageCache;
4004         } else { // cache miss
4005                 if ( $blacklist === null ) {
4006                         $blacklist = wfMsgForContentNoTrans( 'bad_image_list' ); // site list
4007                 }
4008                 # Build the list now
4009                 $badImages = array();
4010                 $lines = explode( "\n", $blacklist );
4011                 foreach( $lines as $line ) {
4012                         # List items only
4013                         if ( substr( $line, 0, 1 ) !== '*' ) {
4014                                 continue;
4015                         }
4016
4017                         # Find all links
4018                         $m = array();
4019                         if ( !preg_match_all( '/\[\[:?(.*?)\]\]/', $line, $m ) ) {
4020                                 continue;
4021                         }
4022
4023                         $exceptions = array();
4024                         $imageDBkey = false;
4025                         foreach ( $m[1] as $i => $titleText ) {
4026                                 $title = Title::newFromText( $titleText );
4027                                 if ( !is_null( $title ) ) {
4028                                         if ( $i == 0 ) {
4029                                                 $imageDBkey = $title->getDBkey();
4030                                         } else {
4031                                                 $exceptions[$title->getPrefixedDBkey()] = true;
4032                                         }
4033                                 }
4034                         }
4035
4036                         if ( $imageDBkey !== false ) {
4037                                 $badImages[$imageDBkey] = $exceptions;
4038                         }
4039                 }
4040                 if ( $cacheable ) {
4041                         $badImageCache = $badImages;
4042                 }
4043         }
4044
4045         $contextKey = $contextTitle ? $contextTitle->getPrefixedDBkey() : false;
4046         $bad = isset( $badImages[$name] ) && !isset( $badImages[$name][$contextKey] );
4047         wfProfileOut( __METHOD__ );
4048         return $bad;
4049 }