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