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 $cache = array(); // Cache of unoutputted messages
 879
 880         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
 881                 return;
 882         }
 883
 884         $timer = wfDebugTimer();
 885         if ( $timer !== '' ) {
 886                 $text = preg_replace( '/[^\n]/', $timer . '\0', $text, 1 );
 887         }
 888
 889         if ( ( $wgDebugComments || $wgShowDebug ) && !$logonly ) {
 890                 $cache[] = $text;
 891
 892                 if ( isset( $wgOut ) && is_object( $wgOut ) ) {
 893                         // add the message and any cached messages to the output
 894                         array_map( array( $wgOut, 'debug' ), $cache );
 895                         $cache = array();
 896                 }
 897         }
 898         if ( wfRunHooks( 'Debug', array( $text, null /* no log group */ ) ) ) {
 899                 if ( $wgDebugLogFile != '' && !$wgProfileOnly ) {
 900                         # Strip unprintables; they can switch terminal modes when binary data
 901                         # gets dumped, which is pretty annoying.
 902                         $text = preg_replace( '![\x00-\x08\x0b\x0c\x0e-\x1f]!', ' ', $text );
 903                         $text = $wgDebugLogPrefix . $text;
 904                         wfErrorLog( $text, $wgDebugLogFile );
 905                 }
 906         }
 907
 908         MWDebug::debugMsg( $text );
 909 }
 910
 911 /**
 912  * Returns true if debug logging should be suppressed if $wgDebugRawPage = false
 913  * @return bool
 914  */
 915 function wfIsDebugRawPage() {
 916         static $cache;
 917         if ( $cache !== null ) {
 918                 return $cache;
 919         }
 920         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
 921         if ( ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' )
 922                 || (
 923                         isset( $_SERVER['SCRIPT_NAME'] )
 924                         && substr( $_SERVER['SCRIPT_NAME'], -8 ) == 'load.php'
 925                 ) )
 926         {
 927                 $cache = true;
 928         } else {
 929                 $cache = false;
 930         }
 931         return $cache;
 932 }
 933
 934 /**
 935  * Get microsecond timestamps for debug logs
 936  *
 937  * @return string
 938  */
 939 function wfDebugTimer() {
 940         global $wgDebugTimestamps, $wgRequestTime;
 941
 942         if ( !$wgDebugTimestamps ) {
 943                 return '';
 944         }
 945
 946         $prefix = sprintf( "%6.4f", microtime( true ) - $wgRequestTime );
 947         $mem = sprintf( "%5.1fM", ( memory_get_usage( true ) / ( 1024 * 1024 ) ) );
 948         return "$prefix $mem  ";
 949 }
 950
 951 /**
 952  * Send a line giving PHP memory usage.
 953  *
 954  * @param $exact Bool: print exact values instead of kilobytes (default: false)
 955  */
 956 function wfDebugMem( $exact = false ) {
 957         $mem = memory_get_usage();
 958         if( !$exact ) {
 959                 $mem = floor( $mem / 1024 ) . ' kilobytes';
 960         } else {
 961                 $mem .= ' bytes';
 962         }
 963         wfDebug( "Memory usage: $mem\n" );
 964 }
 965
 966 /**
 967  * Send a line to a supplementary debug log file, if configured, or main debug log if not.
 968  * $wgDebugLogGroups[$logGroup] should be set to a filename to send to a separate log.
 969  *
 970  * @param $logGroup String
 971  * @param $text String
 972  * @param $public Bool: whether to log the event in the public log if no private
 973  *                     log file is specified, (default true)
 974  */
 975 function wfDebugLog( $logGroup, $text, $public = true ) {
 976         global $wgDebugLogGroups;
 977         $text = trim( $text ) . "\n";
 978         if( isset( $wgDebugLogGroups[$logGroup] ) ) {
 979                 $time = wfTimestamp( TS_DB );
 980                 $wiki = wfWikiID();
 981                 $host = wfHostname();
 982                 if ( wfRunHooks( 'Debug', array( $text, $logGroup ) ) ) {
 983                         wfErrorLog( "$time $host $wiki: $text", $wgDebugLogGroups[$logGroup] );
 984                 }
 985         } elseif ( $public === true ) {
 986                 wfDebug( $text, true );
 987         }
 988 }
 989
 990 /**
 991  * Log for database errors
 992  *
 993  * @param $text String: database error message.
 994  */
 995 function wfLogDBError( $text ) {
 996         global $wgDBerrorLog;
 997         if ( $wgDBerrorLog ) {
 998                 $host = wfHostname();
 999                 $wiki = wfWikiID();
1000                 $text = date( 'D M j G:i:s T Y' ) . "\t$host\t$wiki\t$text";
1001                 wfErrorLog( $text, $wgDBerrorLog );
1002         }
1003 }
1004
1005 /**
1006  * Throws a warning that $function is deprecated
1007  *
1008  * @param $function String
1009  * @param $version String|bool: Version of MediaWiki that the function was deprecated in (Added in 1.19).
1010  * @param $component String|bool: Added in 1.19.
1011  * @param $callerOffset integer: How far up the callstack is the original
1012  *    caller. 2 = function that called the function that called
1013  *    wfDeprecated (Added in 1.20)
1014  *
1015  * @return null
1016  */
1017 function wfDeprecated( $function, $version = false, $component = false, $callerOffset = 2 ) {
1018         static $functionsWarned = array();
1019
1020         MWDebug::deprecated( $function, $version, $component );
1021
1022         if ( !isset( $functionsWarned[$function] ) ) {
1023                 $functionsWarned[$function] = true;
1024
1025                 if ( $version ) {
1026                         global $wgDeprecationReleaseLimit;
1027
1028                         if ( $wgDeprecationReleaseLimit && $component === false ) {
1029                                 # Strip -* off the end of $version so that branches can use the
1030                                 # format #.##-branchname to avoid issues if the branch is merged into
1031                                 # a version of MediaWiki later than what it was branched from
1032                                 $comparableVersion = preg_replace( '/-.*$/', '', $version );
1033
1034                                 # If the comparableVersion is larger than our release limit then
1035                                 # skip the warning message for the deprecation
1036                                 if ( version_compare( $wgDeprecationReleaseLimit, $comparableVersion, '<' ) ) {
1037                                         return;
1038                                 }
1039                         }
1040
1041                         $component = $component === false ? 'MediaWiki' : $component;
1042                         wfWarn( "Use of $function was deprecated in $component $version.", $callerOffset );
1043                 } else {
1044                         wfWarn( "Use of $function is deprecated.", $callerOffset );
1045                 }
1046         }
1047 }
1048
1049 /**
1050  * Send a warning either to the debug log or in a PHP error depending on
1051  * $wgDevelopmentWarnings
1052  *
1053  * @param $msg String: message to send
1054  * @param $callerOffset Integer: number of items to go back in the backtrace to
1055  *        find the correct caller (1 = function calling wfWarn, ...)
1056  * @param $level Integer: PHP error level; only used when $wgDevelopmentWarnings
1057  *        is true
1058  */
1059 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
1060         global $wgDevelopmentWarnings;
1061
1062         MWDebug::warning( $msg, $callerOffset + 2 );
1063
1064         $callers = wfDebugBacktrace();
1065         if ( isset( $callers[$callerOffset + 1] ) ) {
1066                 $callerfunc = $callers[$callerOffset + 1];
1067                 $callerfile = $callers[$callerOffset];
1068                 if ( isset( $callerfile['file'] ) && isset( $callerfile['line'] ) ) {
1069                         $file = $callerfile['file'] . ' at line ' . $callerfile['line'];
1070                 } else {
1071                         $file = '(internal function)';
1072                 }
1073                 $func = '';
1074                 if ( isset( $callerfunc['class'] ) ) {
1075                         $func .= $callerfunc['class'] . '::';
1076                 }
1077                 if ( isset( $callerfunc['function'] ) ) {
1078                         $func .= $callerfunc['function'];
1079                 }
1080                 $msg .= " [Called from $func in $file]";
1081         }
1082
1083         if ( $wgDevelopmentWarnings ) {
1084                 trigger_error( $msg, $level );
1085         } else {
1086                 wfDebug( "$msg\n" );
1087         }
1088 }
1089
1090 /**
1091  * Log to a file without getting "file size exceeded" signals.
1092  *
1093  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
1094  * send lines to the specified port, prefixed by the specified prefix and a space.
1095  *
1096  * @param $text String
1097  * @param $file String filename
1098  */
1099 function wfErrorLog( $text, $file ) {
1100         if ( substr( $file, 0, 4 ) == 'udp:' ) {
1101                 # Needs the sockets extension
1102                 if ( preg_match( '!^(tcp|udp):(?://)?\[([0-9a-fA-F:]+)\]:(\d+)(?:/(.*))?$!', $file, $m ) ) {
1103                         // IPv6 bracketed host
1104                         $host = $m[2];
1105                         $port = intval( $m[3] );
1106                         $prefix = isset( $m[4] ) ? $m[4] : false;
1107                         $domain = AF_INET6;
1108                 } elseif ( preg_match( '!^(tcp|udp):(?://)?([a-zA-Z0-9.-]+):(\d+)(?:/(.*))?$!', $file, $m ) ) {
1109                         $host = $m[2];
1110                         if ( !IP::isIPv4( $host ) ) {
1111                                 $host = gethostbyname( $host );
1112                         }
1113                         $port = intval( $m[3] );
1114                         $prefix = isset( $m[4] ) ? $m[4] : false;
1115                         $domain = AF_INET;
1116                 } else {
1117                         throw new MWException( __METHOD__ . ': Invalid UDP specification' );
1118                 }
1119
1120                 // Clean it up for the multiplexer
1121                 if ( strval( $prefix ) !== '' ) {
1122                         $text = preg_replace( '/^/m', $prefix . ' ', $text );
1123
1124                         // Limit to 64KB
1125                         if ( strlen( $text ) > 65506 ) {
1126                                 $text = substr( $text, 0, 65506 );
1127                         }
1128
1129                         if ( substr( $text, -1 ) != "\n" ) {
1130                                 $text .= "\n";
1131                         }
1132                 } elseif ( strlen( $text ) > 65507 ) {
1133                         $text = substr( $text, 0, 65507 );
1134                 }
1135
1136                 $sock = socket_create( $domain, SOCK_DGRAM, SOL_UDP );
1137                 if ( !$sock ) {
1138                         return;
1139                 }
1140
1141                 socket_sendto( $sock, $text, strlen( $text ), 0, $host, $port );
1142                 socket_close( $sock );
1143         } else {
1144                 wfSuppressWarnings();
1145                 $exists = file_exists( $file );
1146                 $size = $exists ? filesize( $file ) : false;
1147                 if ( !$exists || ( $size !== false && $size + strlen( $text ) < 0x7fffffff ) ) {
1148                         file_put_contents( $file, $text, FILE_APPEND );
1149                 }
1150                 wfRestoreWarnings();
1151         }
1152 }
1153
1154 /**
1155  * @todo document
1156  */
1157 function wfLogProfilingData() {
1158         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
1159         global $wgProfileLimit, $wgUser;
1160
1161         $profiler = Profiler::instance();
1162
1163         # Profiling must actually be enabled...
1164         if ( $profiler->isStub() ) {
1165                 return;
1166         }
1167
1168         // Get total page request time and only show pages that longer than
1169         // $wgProfileLimit time (default is 0)
1170         $elapsed = microtime( true ) - $wgRequestTime;
1171         if ( $elapsed <= $wgProfileLimit ) {
1172                 return;
1173         }
1174
1175         $profiler->logData();
1176
1177         // Check whether this should be logged in the debug file.
1178         if ( $wgDebugLogFile == '' || ( !$wgDebugRawPage && wfIsDebugRawPage() ) ) {
1179                 return;
1180         }
1181
1182         $forward = '';
1183         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
1184                 $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
1185         }
1186         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
1187                 $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
1188         }
1189         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
1190                 $forward .= ' from ' . $_SERVER['HTTP_FROM'];
1191         }
1192         if ( $forward ) {
1193                 $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
1194         }
1195         // Don't load $wgUser at this late stage just for statistics purposes
1196         // @todo FIXME: We can detect some anons even if it is not loaded. See User::getId()
1197         if ( $wgUser->isItemLoaded( 'id' ) && $wgUser->isAnon() ) {
1198                 $forward .= ' anon';
1199         }
1200         $log = sprintf( "%s\t%04.3f\t%s\n",
1201                 gmdate( 'YmdHis' ), $elapsed,
1202                 urldecode( $wgRequest->getRequestURL() . $forward ) );
1203
1204         wfErrorLog( $log . $profiler->getOutput(), $wgDebugLogFile );
1205 }
1206
1207 /**
1208  * Increment a statistics counter
1209  *
1210  * @param $key String
1211  * @param $count Int
1212  */
1213 function wfIncrStats( $key, $count = 1 ) {
1214         global $wgStatsMethod;
1215
1216         $count = intval( $count );
1217
1218         if( $wgStatsMethod == 'udp' ) {
1219                 global $wgUDPProfilerHost, $wgUDPProfilerPort, $wgDBname, $wgAggregateStatsID;
1220                 static $socket;
1221
1222                 $id = $wgAggregateStatsID !== false ? $wgAggregateStatsID : $wgDBname;
1223
1224                 if ( !$socket ) {
1225                         $socket = socket_create( AF_INET, SOCK_DGRAM, SOL_UDP );
1226                         $statline = "stats/{$id} - 1 1 1 1 1 -total\n";
1227                         socket_sendto(
1228                                 $socket,
1229                                 $statline,
1230                                 strlen( $statline ),
1231                                 0,
1232                                 $wgUDPProfilerHost,
1233                                 $wgUDPProfilerPort
1234                         );
1235                 }
1236                 $statline = "stats/{$id} - {$count} 1 1 1 1 {$key}\n";
1237                 wfSuppressWarnings();
1238                 socket_sendto(
1239                         $socket,
1240                         $statline,
1241                         strlen( $statline ),
1242                         0,
1243                         $wgUDPProfilerHost,
1244                         $wgUDPProfilerPort
1245                 );
1246                 wfRestoreWarnings();
1247         } elseif( $wgStatsMethod == 'cache' ) {
1248                 global $wgMemc;
1249                 $key = wfMemcKey( 'stats', $key );
1250                 if ( is_null( $wgMemc->incr( $key, $count ) ) ) {
1251                         $wgMemc->add( $key, $count );
1252                 }
1253         } else {
1254                 // Disabled
1255         }
1256 }
1257
1258 /**
1259  * Check if the wiki read-only lock file is present. This can be used to lock
1260  * off editing functions, but doesn't guarantee that the database will not be
1261  * modified.
1262  *
1263  * @return bool
1264  */
1265 function wfReadOnly() {
1266         global $wgReadOnlyFile, $wgReadOnly;
1267
1268         if ( !is_null( $wgReadOnly ) ) {
1269                 return (bool)$wgReadOnly;
1270         }
1271         if ( $wgReadOnlyFile == '' ) {
1272                 return false;
1273         }
1274         // Set $wgReadOnly for faster access next time
1275         if ( is_file( $wgReadOnlyFile ) ) {
1276                 $wgReadOnly = file_get_contents( $wgReadOnlyFile );
1277         } else {
1278                 $wgReadOnly = false;
1279         }
1280         return (bool)$wgReadOnly;
1281 }
1282
1283 /**
1284  * @return bool
1285  */
1286 function wfReadOnlyReason() {
1287         global $wgReadOnly;
1288         wfReadOnly();
1289         return $wgReadOnly;
1290 }
1291
1292 /**
1293  * Return a Language object from $langcode
1294  *
1295  * @param $langcode Mixed: either:
1296  *                  - a Language object
1297  *                  - code of the language to get the message for, if it is
1298  *                    a valid code create a language for that language, if
1299  *                    it is a string but not a valid code then make a basic
1300  *                    language object
1301  *                  - a boolean: if it's false then use the global object for
1302  *                    the current user's language (as a fallback for the old parameter
1303  *                    functionality), or if it is true then use global object
1304  *                    for the wiki's content language.
1305  * @return Language object
1306  */
1307 function wfGetLangObj( $langcode = false ) {
1308         # Identify which language to get or create a language object for.
1309         # Using is_object here due to Stub objects.
1310         if( is_object( $langcode ) ) {
1311                 # Great, we already have the object (hopefully)!
1312                 return $langcode;
1313         }
1314
1315         global $wgContLang, $wgLanguageCode;
1316         if( $langcode === true || $langcode === $wgLanguageCode ) {
1317                 # $langcode is the language code of the wikis content language object.
1318                 # or it is a boolean and value is true
1319                 return $wgContLang;
1320         }
1321
1322         global $wgLang;
1323         if( $langcode === false || $langcode === $wgLang->getCode() ) {
1324                 # $langcode is the language code of user language object.
1325                 # or it was a boolean and value is false
1326                 return $wgLang;
1327         }
1328
1329         $validCodes = array_keys( Language::fetchLanguageNames() );
1330         if( in_array( $langcode, $validCodes ) ) {
1331                 # $langcode corresponds to a valid language.
1332                 return Language::factory( $langcode );
1333         }
1334
1335         # $langcode is a string, but not a valid language code; use content language.
1336         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
1337         return $wgContLang;
1338 }
1339
1340 /**
1341  * Old function when $wgBetterDirectionality existed
1342  * All usage removed, wfUILang can be removed in near future
1343  *
1344  * @deprecated since 1.18
1345  * @return Language
1346  */
1347 function wfUILang() {
1348         wfDeprecated( __METHOD__, '1.18' );
1349         global $wgLang;
1350         return $wgLang;
1351 }
1352
1353 /**
1354  * This is the new function for getting translated interface messages.
1355  * See the Message class for documentation how to use them.
1356  * The intention is that this function replaces all old wfMsg* functions.
1357  * @param $key \string Message key.
1358  * Varargs: normal message parameters.
1359  * @return Message
1360  * @since 1.17
1361  */
1362 function wfMessage( $key /*...*/) {
1363         $params = func_get_args();
1364         array_shift( $params );
1365         if ( isset( $params[0] ) && is_array( $params[0] ) ) {
1366                 $params = $params[0];
1367         }
1368         return new Message( $key, $params );
1369 }
1370
1371 /**
1372  * This function accepts multiple message keys and returns a message instance
1373  * for the first message which is non-empty. If all messages are empty then an
1374  * instance of the first message key is returned.
1375  * @param varargs: message keys
1376  * @return Message
1377  * @since 1.18
1378  */
1379 function wfMessageFallback( /*...*/ ) {
1380         $args = func_get_args();
1381         return MWFunction::callArray( 'Message::newFallbackSequence', $args );
1382 }
1383
1384 /**
1385  * Get a message from anywhere, for the current user language.
1386  *
1387  * Use wfMsgForContent() instead if the message should NOT
1388  * change depending on the user preferences.
1389  *
1390  * @param $key String: lookup key for the message, usually
1391  *    defined in languages/Language.php
1392  *
1393  * Parameters to the message, which can be used to insert variable text into
1394  * it, can be passed to this function in the following formats:
1395  * - One per argument, starting at the second parameter
1396  * - As an array in the second parameter
1397  * These are not shown in the function definition.
1398  *
1399  * @return String
1400  */
1401 function wfMsg( $key ) {
1402         $args = func_get_args();
1403         array_shift( $args );
1404         return wfMsgReal( $key, $args );
1405 }
1406
1407 /**
1408  * Same as above except doesn't transform the message
1409  *
1410  * @param $key String
1411  * @return String
1412  */
1413 function wfMsgNoTrans( $key ) {
1414         $args = func_get_args();
1415         array_shift( $args );
1416         return wfMsgReal( $key, $args, true, false, false );
1417 }
1418
1419 /**
1420  * Get a message from anywhere, for the current global language
1421  * set with $wgLanguageCode.
1422  *
1423  * Use this if the message should NOT change dependent on the
1424  * language set in the user's preferences. This is the case for
1425  * most text written into logs, as well as link targets (such as
1426  * the name of the copyright policy page). Link titles, on the
1427  * other hand, should be shown in the UI language.
1428  *
1429  * Note that MediaWiki allows users to change the user interface
1430  * language in their preferences, but a single installation
1431  * typically only contains content in one language.
1432  *
1433  * Be wary of this distinction: If you use wfMsg() where you should
1434  * use wfMsgForContent(), a user of the software may have to
1435  * customize potentially hundreds of messages in
1436  * order to, e.g., fix a link in every possible language.
1437  *
1438  * @param $key String: lookup key for the message, usually
1439  *     defined in languages/Language.php
1440  * @return String
1441  */
1442 function wfMsgForContent( $key ) {
1443         global $wgForceUIMsgAsContentMsg;
1444         $args = func_get_args();
1445         array_shift( $args );
1446         $forcontent = true;
1447         if( is_array( $wgForceUIMsgAsContentMsg ) &&
1448                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
1449         {
1450                 $forcontent = false;
1451         }
1452         return wfMsgReal( $key, $args, true, $forcontent );
1453 }
1454
1455 /**
1456  * Same as above except doesn't transform the message
1457  *
1458  * @param $key String
1459  * @return String
1460  */
1461 function wfMsgForContentNoTrans( $key ) {
1462         global $wgForceUIMsgAsContentMsg;
1463         $args = func_get_args();
1464         array_shift( $args );
1465         $forcontent = true;
1466         if( is_array( $wgForceUIMsgAsContentMsg ) &&
1467                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
1468         {
1469                 $forcontent = false;
1470         }
1471         return wfMsgReal( $key, $args, true, $forcontent, false );
1472 }
1473
1474 /**
1475  * Really get a message
1476  *
1477  * @param $key String: key to get.
1478  * @param $args
1479  * @param $useDB Boolean
1480  * @param $forContent Mixed: Language code, or false for user lang, true for content lang.
1481  * @param $transform Boolean: Whether or not to transform the message.
1482  * @return String: the requested message.
1483  */
1484 function wfMsgReal( $key, $args, $useDB = true, $forContent = false, $transform = true ) {
1485         wfProfileIn( __METHOD__ );
1486         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
1487         $message = wfMsgReplaceArgs( $message, $args );
1488         wfProfileOut( __METHOD__ );
1489         return $message;
1490 }
1491
1492 /**
1493  * Fetch a message string value, but don't replace any keys yet.
1494  *
1495  * @param $key String
1496  * @param $useDB Bool
1497  * @param $langCode String: Code of the language to get the message for, or
1498  *                  behaves as a content language switch if it is a boolean.
1499  * @param $transform Boolean: whether to parse magic words, etc.
1500  * @return string
1501  */
1502 function wfMsgGetKey( $key, $useDB = true, $langCode = false, $transform = true ) {
1503         wfRunHooks( 'NormalizeMessageKey', array( &$key, &$useDB, &$langCode, &$transform ) );
1504
1505         $cache = MessageCache::singleton();
1506         $message = $cache->get( $key, $useDB, $langCode );
1507         if( $message === false ) {
1508                 $message = '&lt;' . htmlspecialchars( $key ) . '&gt;';
1509         } elseif ( $transform ) {
1510                 $message = $cache->transform( $message );
1511         }
1512         return $message;
1513 }
1514
1515 /**
1516  * Replace message parameter keys on the given formatted output.
1517  *
1518  * @param $message String
1519  * @param $args Array
1520  * @return string
1521  * @private
1522  */
1523 function wfMsgReplaceArgs( $message, $args ) {
1524         # Fix windows line-endings
1525         # Some messages are split with explode("\n", $msg)
1526         $message = str_replace( "\r", '', $message );
1527
1528         // Replace arguments
1529         if ( count( $args ) ) {
1530                 if ( is_array( $args[0] ) ) {
1531                         $args = array_values( $args[0] );
1532                 }
1533                 $replacementKeys = array();
1534                 foreach( $args as $n => $param ) {
1535                         $replacementKeys['$' . ( $n + 1 )] = $param;
1536                 }
1537                 $message = strtr( $message, $replacementKeys );
1538         }
1539
1540         return $message;
1541 }
1542
1543 /**
1544  * Return an HTML-escaped version of a message.
1545  * Parameter replacements, if any, are done *after* the HTML-escaping,
1546  * so parameters may contain HTML (eg links or form controls). Be sure
1547  * to pre-escape them if you really do want plaintext, or just wrap
1548  * the whole thing in htmlspecialchars().
1549  *
1550  * @param $key String
1551  * @param string ... parameters
1552  * @return string
1553  */
1554 function wfMsgHtml( $key ) {
1555         $args = func_get_args();
1556         array_shift( $args );
1557         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key ) ), $args );
1558 }
1559
1560 /**
1561  * Return an HTML version of message
1562  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
1563  * so parameters may contain HTML (eg links or form controls). Be sure
1564  * to pre-escape them if you really do want plaintext, or just wrap
1565  * the whole thing in htmlspecialchars().
1566  *
1567  * @param $key String
1568  * @param string ... parameters
1569  * @return string
1570  */
1571 function wfMsgWikiHtml( $key ) {
1572         $args = func_get_args();
1573         array_shift( $args );
1574         return wfMsgReplaceArgs(
1575                 MessageCache::singleton()->parse( wfMsgGetKey( $key ), null,
1576                 /* can't be set to false */ true, /* interface */ true )->getText(),
1577                 $args );
1578 }
1579
1580 /**
1581  * Returns message in the requested format
1582  * @param $key String: key of the message
1583  * @param $options Array: processing rules. Can take the following options:
1584  *   <i>parse</i>: parses wikitext to HTML
1585  *   <i>parseinline</i>: parses wikitext to HTML and removes the surrounding
1586  *       p's added by parser or tidy
1587  *   <i>escape</i>: filters message through htmlspecialchars
1588  *   <i>escapenoentities</i>: same, but allows entity references like &#160; through
1589  *   <i>replaceafter</i>: parameters are substituted after parsing or escaping
1590  *   <i>parsemag</i>: transform the message using magic phrases
1591  *   <i>content</i>: fetch message for content language instead of interface
1592  * Also can accept a single associative argument, of the form 'language' => 'xx':
1593  *   <i>language</i>: Language object or language code to fetch message for
1594  *       (overriden by <i>content</i>).
1595  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
1596  *
1597  * @return String
1598  */
1599 function wfMsgExt( $key, $options ) {
1600         $args = func_get_args();
1601         array_shift( $args );
1602         array_shift( $args );
1603         $options = (array)$options;
1604
1605         foreach( $options as $arrayKey => $option ) {
1606                 if( !preg_match( '/^[0-9]+|language$/', $arrayKey ) ) {
1607                         # An unknown index, neither numeric nor "language"
1608                         wfWarn( "wfMsgExt called with incorrect parameter key $arrayKey", 1, E_USER_WARNING );
1609                 } elseif( preg_match( '/^[0-9]+$/', $arrayKey ) && !in_array( $option,
1610                 array( 'parse', 'parseinline', 'escape', 'escapenoentities',
1611                 'replaceafter', 'parsemag', 'content' ) ) ) {
1612                         # A numeric index with unknown value
1613                         wfWarn( "wfMsgExt called with incorrect parameter $option", 1, E_USER_WARNING );
1614                 }
1615         }
1616
1617         if( in_array( 'content', $options, true ) ) {
1618                 $forContent = true;
1619                 $langCode = true;
1620                 $langCodeObj = null;
1621         } elseif( array_key_exists( 'language', $options ) ) {
1622                 $forContent = false;
1623                 $langCode = wfGetLangObj( $options['language'] );
1624                 $langCodeObj = $langCode;
1625         } else {
1626                 $forContent = false;
1627                 $langCode = false;
1628                 $langCodeObj = null;
1629         }
1630
1631         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
1632
1633         if( !in_array( 'replaceafter', $options, true ) ) {
1634                 $string = wfMsgReplaceArgs( $string, $args );
1635         }
1636
1637         $messageCache = MessageCache::singleton();
1638         $parseInline = in_array( 'parseinline', $options, true );
1639         if( in_array( 'parse', $options, true ) || $parseInline ) {
1640                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj );
1641                 if ( $string instanceof ParserOutput ) {
1642                         $string = $string->getText();
1643                 }
1644
1645                 if ( $parseInline ) {
1646                         $m = array();
1647                         if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
1648                                 $string = $m[1];
1649                         }
1650                 }
1651         } elseif ( in_array( 'parsemag', $options, true ) ) {
1652                 $string = $messageCache->transform( $string,
1653                                 !$forContent, $langCodeObj );
1654         }
1655
1656         if ( in_array( 'escape', $options, true ) ) {
1657                 $string = htmlspecialchars ( $string );
1658         } elseif ( in_array( 'escapenoentities', $options, true ) ) {
1659                 $string = Sanitizer::escapeHtmlAllowEntities( $string );
1660         }
1661
1662         if( in_array( 'replaceafter', $options, true ) ) {
1663                 $string = wfMsgReplaceArgs( $string, $args );
1664         }
1665
1666         return $string;
1667 }
1668
1669 /**
1670  * Since wfMsg() and co suck, they don't return false if the message key they
1671  * looked up didn't exist but a XHTML string, this function checks for the
1672  * nonexistance of messages by checking the MessageCache::get() result directly.
1673  *
1674  * @param $key      String: the message key looked up
1675  * @return Boolean True if the message *doesn't* exist.
1676  */
1677 function wfEmptyMsg( $key ) {
1678         return MessageCache::singleton()->get( $key, /*useDB*/true, /*content*/false ) === false;
1679 }
1680
1681 /**
1682  * Throw a debugging exception. This function previously once exited the process,
1683  * but now throws an exception instead, with similar results.
1684  *
1685  * @param $msg String: message shown when dying.
1686  */
1687 function wfDebugDieBacktrace( $msg = '' ) {
1688         throw new MWException( $msg );
1689 }
1690
1691 /**
1692  * Fetch server name for use in error reporting etc.
1693  * Use real server name if available, so we know which machine
1694  * in a server farm generated the current page.
1695  *
1696  * @return string
1697  */
1698 function wfHostname() {
1699         static $host;
1700         if ( is_null( $host ) ) {
1701                 if ( function_exists( 'posix_uname' ) ) {
1702                         // This function not present on Windows
1703                         $uname = posix_uname();
1704                 } else {
1705                         $uname = false;
1706                 }
1707                 if( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1708                         $host = $uname['nodename'];
1709                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1710                         # Windows computer name
1711                         $host = getenv( 'COMPUTERNAME' );
1712                 } else {
1713                         # This may be a virtual server.
1714                         $host = $_SERVER['SERVER_NAME'];
1715                 }
1716         }
1717         return $host;
1718 }
1719
1720 /**
1721  * Returns a HTML comment with the elapsed time since request.
1722  * This method has no side effects.
1723  *
1724  * @return string
1725  */
1726 function wfReportTime() {
1727         global $wgRequestTime, $wgShowHostnames;
1728
1729         $elapsed = microtime( true ) - $wgRequestTime;
1730
1731         return $wgShowHostnames
1732                 ? sprintf( '<!-- Served by %s in %01.3f secs. -->', wfHostname(), $elapsed )
1733                 : sprintf( '<!-- Served in %01.3f secs. -->', $elapsed );
1734 }
1735
1736 /**
1737  * Safety wrapper for debug_backtrace().
1738  *
1739  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
1740  * murky circumstances, which may be triggered in part by stub objects
1741  * or other fancy talkin'.
1742  *
1743  * Will return an empty array if Zend Optimizer is detected or if
1744  * debug_backtrace is disabled, otherwise the output from
1745  * debug_backtrace() (trimmed).
1746  *
1747  * @param $limit int This parameter can be used to limit the number of stack frames returned
1748  *
1749  * @return array of backtrace information
1750  */
1751 function wfDebugBacktrace( $limit = 0 ) {
1752         static $disabled = null;
1753
1754         if( extension_loaded( 'Zend Optimizer' ) ) {
1755                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
1756                 return array();
1757         }
1758
1759         if ( is_null( $disabled ) ) {
1760                 $disabled = false;
1761                 $functions = explode( ',', ini_get( 'disable_functions' ) );
1762                 $functions = array_map( 'trim', $functions );
1763                 $functions = array_map( 'strtolower', $functions );
1764                 if ( in_array( 'debug_backtrace', $functions ) ) {
1765                         wfDebug( "debug_backtrace is in disabled_functions\n" );
1766                         $disabled = true;
1767                 }
1768         }
1769         if ( $disabled ) {
1770                 return array();
1771         }
1772
1773         if ( $limit && version_compare( PHP_VERSION, '5.4.0', '>=' ) ) {
1774                 return array_slice( debug_backtrace( DEBUG_BACKTRACE_PROVIDE_OBJECT, $limit ), 1 );
1775         } else {
1776                 return array_slice( debug_backtrace(), 1 );
1777         }
1778 }
1779
1780 /**
1781  * Get a debug backtrace as a string
1782  *
1783  * @return string
1784  */
1785 function wfBacktrace() {
1786         global $wgCommandLineMode;
1787
1788         if ( $wgCommandLineMode ) {
1789                 $msg = '';
1790         } else {
1791                 $msg = "<ul>\n";
1792         }
1793         $backtrace = wfDebugBacktrace();
1794         foreach( $backtrace as $call ) {
1795                 if( isset( $call['file'] ) ) {
1796                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
1797                         $file = $f[count( $f ) - 1];
1798                 } else {
1799                         $file = '-';
1800                 }
1801                 if( isset( $call['line'] ) ) {
1802                         $line = $call['line'];
1803                 } else {
1804                         $line = '-';
1805                 }
1806                 if ( $wgCommandLineMode ) {
1807                         $msg .= "$file line $line calls ";
1808                 } else {
1809                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
1810                 }
1811                 if( !empty( $call['class'] ) ) {
1812                         $msg .= $call['class'] . $call['type'];
1813                 }
1814                 $msg .= $call['function'] . '()';
1815
1816                 if ( $wgCommandLineMode ) {
1817                         $msg .= "\n";
1818                 } else {
1819                         $msg .= "</li>\n";
1820                 }
1821         }
1822         if ( $wgCommandLineMode ) {
1823                 $msg .= "\n";
1824         } else {
1825                 $msg .= "</ul>\n";
1826         }
1827
1828         return $msg;
1829 }
1830
1831 /**
1832  * Get the name of the function which called this function
1833  *
1834  * @param $level Int
1835  * @return Bool|string
1836  */
1837 function wfGetCaller( $level = 2 ) {
1838         $backtrace = wfDebugBacktrace( $level );
1839         if ( isset( $backtrace[$level] ) ) {
1840                 return wfFormatStackFrame( $backtrace[$level] );
1841         } else {
1842                 $caller = 'unknown';
1843         }
1844         return $caller;
1845 }
1846
1847 /**
1848  * Return a string consisting of callers in the stack. Useful sometimes
1849  * for profiling specific points.
1850  *
1851  * @param $limit int The maximum depth of the stack frame to return, or false for
1852  *               the entire stack.
1853  * @return String
1854  */
1855 function wfGetAllCallers( $limit = 3 ) {
1856         $trace = array_reverse( wfDebugBacktrace() );
1857         if ( !$limit || $limit > count( $trace ) - 1 ) {
1858                 $limit = count( $trace ) - 1;
1859         }
1860         $trace = array_slice( $trace, -$limit - 1, $limit );
1861         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1862 }
1863
1864 /**
1865  * Return a string representation of frame
1866  *
1867  * @param $frame Array
1868  * @return Bool
1869  */
1870 function wfFormatStackFrame( $frame ) {
1871         return isset( $frame['class'] ) ?
1872                 $frame['class'] . '::' . $frame['function'] :
1873                 $frame['function'];
1874 }
1875
1876
1877 /* Some generic result counters, pulled out of SearchEngine */
1878
1879
1880 /**
1881  * @todo document
1882  *
1883  * @param $offset Int
1884  * @param $limit Int
1885  * @return String
1886  */
1887 function wfShowingResults( $offset, $limit ) {
1888         global $wgLang;
1889         return wfMsgExt(
1890                 'showingresults',
1891                 array( 'parseinline' ),
1892                 $wgLang->formatNum( $limit ),
1893                 $wgLang->formatNum( $offset + 1 )
1894         );
1895 }
1896
1897 /**
1898  * Generate (prev x| next x) (20|50|100...) type links for paging
1899  *
1900  * @param $offset String
1901  * @param $limit Integer
1902  * @param $link String
1903  * @param $query String: optional URL query parameter string
1904  * @param $atend Bool: optional param for specified if this is the last page
1905  * @return String
1906  * @deprecated in 1.19; use Language::viewPrevNext() instead
1907  */
1908 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
1909         wfDeprecated( __METHOD__, '1.19' );
1910
1911         global $wgLang;
1912
1913         $query = wfCgiToArray( $query );
1914
1915         if( is_object( $link ) ) {
1916                 $title = $link;
1917         } else {
1918                 $title = Title::newFromText( $link );
1919                 if( is_null( $title ) ) {
1920                         return false;
1921                 }
1922         }
1923
1924         return $wgLang->viewPrevNext( $title, $offset, $limit, $query, $atend );
1925 }
1926
1927 /**
1928  * Make a list item, used by various special pages
1929  *
1930  * @param $page String Page link
1931  * @param $details String Text between brackets
1932  * @param $oppositedm Boolean   Add the direction mark opposite to your
1933  *                                                              language, to display text properly
1934  * @return String
1935  * @deprecated since 1.19; use Language::specialList() instead
1936  */
1937 function wfSpecialList( $page, $details, $oppositedm = true ) {
1938         wfDeprecated( __METHOD__, '1.19' );
1939
1940         global $wgLang;
1941         return $wgLang->specialList( $page, $details, $oppositedm );
1942 }
1943
1944 /**
1945  * @todo document
1946  * @todo FIXME: We may want to blacklist some broken browsers
1947  *
1948  * @param $force Bool
1949  * @return bool Whereas client accept gzip compression
1950  */
1951 function wfClientAcceptsGzip( $force = false ) {
1952         static $result = null;
1953         if ( $result === null || $force ) {
1954                 $result = false;
1955                 if( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1956                         # @todo FIXME: We may want to blacklist some broken browsers
1957                         $m = array();
1958                         if( preg_match(
1959                                 '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1960                                 $_SERVER['HTTP_ACCEPT_ENCODING'],
1961                                 $m )
1962                         )
1963                         {
1964                                 if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1965                                         $result = false;
1966                                         return $result;
1967                                 }
1968                                 wfDebug( "wfClientAcceptsGzip: client accepts gzip.\n" );
1969                                 $result = true;
1970                         }
1971                 }
1972         }
1973         return $result;
1974 }
1975
1976 /**
1977  * Obtain the offset and limit values from the request string;
1978  * used in special pages
1979  *
1980  * @param $deflimit Int default limit if none supplied
1981  * @param $optionname String Name of a user preference to check against
1982  * @return array
1983  *
1984  */
1985 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
1986         global $wgRequest;
1987         return $wgRequest->getLimitOffset( $deflimit, $optionname );
1988 }
1989
1990 /**
1991  * Escapes the given text so that it may be output using addWikiText()
1992  * without any linking, formatting, etc. making its way through. This
1993  * is achieved by substituting certain characters with HTML entities.
1994  * As required by the callers, <nowiki> is not used.
1995  *
1996  * @param $text String: text to be escaped
1997  * @return String
1998  */
1999 function wfEscapeWikiText( $text ) {
2000         $text = strtr( "\n$text", array(
2001                 '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
2002                 '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
2003                 '{' => '&#123;', '|' => '&#124;', '}' => '&#125;',
2004                 "\n#" => "\n&#35;", "\n*" => "\n&#42;",
2005                 "\n:" => "\n&#58;", "\n;" => "\n&#59;",
2006                 '://' => '&#58;//', 'ISBN ' => 'ISBN&#32;', 'RFC ' => 'RFC&#32;',
2007         ) );
2008         return substr( $text, 1 );
2009 }
2010
2011 /**
2012  * Get the current unix timetstamp with microseconds.  Useful for profiling
2013  * @return Float
2014  */
2015 function wfTime() {
2016         return microtime( true );
2017 }
2018
2019 /**
2020  * Sets dest to source and returns the original value of dest
2021  * If source is NULL, it just returns the value, it doesn't set the variable
2022  * If force is true, it will set the value even if source is NULL
2023  *
2024  * @param $dest Mixed
2025  * @param $source Mixed
2026  * @param $force Bool
2027  * @return Mixed
2028  */
2029 function wfSetVar( &$dest, $source, $force = false ) {
2030         $temp = $dest;
2031         if ( !is_null( $source ) || $force ) {
2032                 $dest = $source;
2033         }
2034         return $temp;
2035 }
2036
2037 /**
2038  * As for wfSetVar except setting a bit
2039  *
2040  * @param $dest Int
2041  * @param $bit Int
2042  * @param $state Bool
2043  *
2044  * @return bool
2045  */
2046 function wfSetBit( &$dest, $bit, $state = true ) {
2047         $temp = (bool)( $dest & $bit );
2048         if ( !is_null( $state ) ) {
2049                 if ( $state ) {
2050                         $dest |= $bit;
2051                 } else {
2052                         $dest &= ~$bit;
2053                 }
2054         }
2055         return $temp;
2056 }
2057
2058 /**
2059  * A wrapper around the PHP function var_export().
2060  * Either print it or add it to the regular output ($wgOut).
2061  *
2062  * @param $var mixed A PHP variable to dump.
2063  */
2064 function wfVarDump( $var ) {
2065         global $wgOut;
2066         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
2067         if ( headers_sent() || !isset( $wgOut ) || !is_object( $wgOut ) ) {
2068                 print $s;
2069         } else {
2070                 $wgOut->addHTML( $s );
2071         }
2072 }
2073
2074 /**
2075  * Provide a simple HTTP error.
2076  *
2077  * @param $code Int|String
2078  * @param $label String
2079  * @param $desc String
2080  */
2081 function wfHttpError( $code, $label, $desc ) {
2082         global $wgOut;
2083         $wgOut->disable();
2084         header( "HTTP/1.0 $code $label" );
2085         header( "Status: $code $label" );
2086         $wgOut->sendCacheControl();
2087
2088         header( 'Content-type: text/html; charset=utf-8' );
2089         print "<!doctype html>" .
2090                 '<html><head><title>' .
2091                 htmlspecialchars( $label ) .
2092                 '</title></head><body><h1>' .
2093                 htmlspecialchars( $label ) .
2094                 '</h1><p>' .
2095                 nl2br( htmlspecialchars( $desc ) ) .
2096                 "</p></body></html>\n";
2097 }
2098
2099 /**
2100  * Clear away any user-level output buffers, discarding contents.
2101  *
2102  * Suitable for 'starting afresh', for instance when streaming
2103  * relatively large amounts of data without buffering, or wanting to
2104  * output image files without ob_gzhandler's compression.
2105  *
2106  * The optional $resetGzipEncoding parameter controls suppression of
2107  * the Content-Encoding header sent by ob_gzhandler; by default it
2108  * is left. See comments for wfClearOutputBuffers() for why it would
2109  * be used.
2110  *
2111  * Note that some PHP configuration options may add output buffer
2112  * layers which cannot be removed; these are left in place.
2113  *
2114  * @param $resetGzipEncoding Bool
2115  */
2116 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
2117         if( $resetGzipEncoding ) {
2118                 // Suppress Content-Encoding and Content-Length
2119                 // headers from 1.10+s wfOutputHandler
2120                 global $wgDisableOutputCompression;
2121                 $wgDisableOutputCompression = true;
2122         }
2123         while( $status = ob_get_status() ) {
2124                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
2125                         // Probably from zlib.output_compression or other
2126                         // PHP-internal setting which can't be removed.
2127                         //
2128                         // Give up, and hope the result doesn't break
2129                         // output behavior.
2130                         break;
2131                 }
2132                 if( !ob_end_clean() ) {
2133                         // Could not remove output buffer handler; abort now
2134                         // to avoid getting in some kind of infinite loop.
2135                         break;
2136                 }
2137                 if( $resetGzipEncoding ) {
2138                         if( $status['name'] == 'ob_gzhandler' ) {
2139                                 // Reset the 'Content-Encoding' field set by this handler
2140                                 // so we can start fresh.
2141                                 if ( function_exists( 'header_remove' ) ) {
2142                                         // Available since PHP 5.3.0
2143                                         header_remove( 'Content-Encoding' );
2144                                 } else {
2145                                         // We need to provide a valid content-coding. See bug 28069
2146                                         header( 'Content-Encoding: identity' );
2147                                 }
2148                                 break;
2149                         }
2150                 }
2151         }
2152 }
2153
2154 /**
2155  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
2156  *
2157  * Clear away output buffers, but keep the Content-Encoding header
2158  * produced by ob_gzhandler, if any.
2159  *
2160  * This should be used for HTTP 304 responses, where you need to
2161  * preserve the Content-Encoding header of the real result, but
2162  * also need to suppress the output of ob_gzhandler to keep to spec
2163  * and avoid breaking Firefox in rare cases where the headers and
2164  * body are broken over two packets.
2165  */
2166 function wfClearOutputBuffers() {
2167         wfResetOutputBuffers( false );
2168 }
2169
2170 /**
2171  * Converts an Accept-* header into an array mapping string values to quality
2172  * factors
2173  *
2174  * @param $accept String
2175  * @param $def String default
2176  * @return Array
2177  */
2178 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
2179         # No arg means accept anything (per HTTP spec)
2180         if( !$accept ) {
2181                 return array( $def => 1.0 );
2182         }
2183
2184         $prefs = array();
2185
2186         $parts = explode( ',', $accept );
2187
2188         foreach( $parts as $part ) {
2189                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
2190                 $values = explode( ';', trim( $part ) );
2191                 $match = array();
2192                 if ( count( $values ) == 1 ) {
2193                         $prefs[$values[0]] = 1.0;
2194                 } elseif ( preg_match( '/q\s*=\s*(\d*\.\d+)/', $values[1], $match ) ) {
2195                         $prefs[$values[0]] = floatval( $match[1] );
2196                 }
2197         }
2198
2199         return $prefs;
2200 }
2201
2202 /**
2203  * Checks if a given MIME type matches any of the keys in the given
2204  * array. Basic wildcards are accepted in the array keys.
2205  *
2206  * Returns the matching MIME type (or wildcard) if a match, otherwise
2207  * NULL if no match.
2208  *
2209  * @param $type String
2210  * @param $avail Array
2211  * @return string
2212  * @private
2213  */
2214 function mimeTypeMatch( $type, $avail ) {
2215         if( array_key_exists( $type, $avail ) ) {
2216                 return $type;
2217         } else {
2218                 $parts = explode( '/', $type );
2219                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
2220                         return $parts[0] . '/*';
2221                 } elseif( array_key_exists( '*/*', $avail ) ) {
2222                         return '*/*';
2223                 } else {
2224                         return null;
2225                 }
2226         }
2227 }
2228
2229 /**
2230  * Returns the 'best' match between a client's requested internet media types
2231  * and the server's list of available types. Each list should be an associative
2232  * array of type to preference (preference is a float between 0.0 and 1.0).
2233  * Wildcards in the types are acceptable.
2234  *
2235  * @param $cprefs Array: client's acceptable type list
2236  * @param $sprefs Array: server's offered types
2237  * @return string
2238  *
2239  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
2240  * XXX: generalize to negotiate other stuff
2241  */
2242 function wfNegotiateType( $cprefs, $sprefs ) {
2243         $combine = array();
2244
2245         foreach( array_keys( $sprefs ) as $type ) {
2246                 $parts = explode( '/', $type );
2247                 if( $parts[1] != '*' ) {
2248                         $ckey = mimeTypeMatch( $type, $cprefs );
2249                         if( $ckey ) {
2250                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
2251                         }
2252                 }
2253         }
2254
2255         foreach( array_keys( $cprefs ) as $type ) {
2256                 $parts = explode( '/', $type );
2257                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
2258                         $skey = mimeTypeMatch( $type, $sprefs );
2259                         if( $skey ) {
2260                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
2261                         }
2262                 }
2263         }
2264
2265         $bestq = 0;
2266         $besttype = null;
2267
2268         foreach( array_keys( $combine ) as $type ) {
2269                 if( $combine[$type] > $bestq ) {
2270                         $besttype = $type;
2271                         $bestq = $combine[$type];
2272                 }
2273         }
2274
2275         return $besttype;
2276 }
2277
2278 /**
2279  * Reference-counted warning suppression
2280  *
2281  * @param $end Bool
2282  */
2283 function wfSuppressWarnings( $end = false ) {
2284         static $suppressCount = 0;
2285         static $originalLevel = false;
2286
2287         if ( $end ) {
2288                 if ( $suppressCount ) {
2289                         --$suppressCount;
2290                         if ( !$suppressCount ) {
2291                                 error_reporting( $originalLevel );
2292                         }
2293                 }
2294         } else {
2295                 if ( !$suppressCount ) {
2296                         // E_DEPRECATED is undefined in PHP 5.2
2297                         if( !defined( 'E_DEPRECATED' ) ) {
2298                                 define( 'E_DEPRECATED', 8192 );
2299                         }
2300                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE | E_USER_WARNING | E_USER_NOTICE | E_DEPRECATED ) );
2301                 }
2302                 ++$suppressCount;
2303         }
2304 }
2305
2306 /**
2307  * Restore error level to previous value
2308  */
2309 function wfRestoreWarnings() {
2310         wfSuppressWarnings( true );
2311 }
2312
2313 # Autodetect, convert and provide timestamps of various types
2314
2315 /**
2316  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
2317  */
2318 define( 'TS_UNIX', 0 );
2319
2320 /**
2321  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
2322  */
2323 define( 'TS_MW', 1 );
2324
2325 /**
2326  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
2327  */
2328 define( 'TS_DB', 2 );
2329
2330 /**
2331  * RFC 2822 format, for E-mail and HTTP headers
2332  */
2333 define( 'TS_RFC2822', 3 );
2334
2335 /**
2336  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
2337  *
2338  * This is used by Special:Export
2339  */
2340 define( 'TS_ISO_8601', 4 );
2341
2342 /**
2343  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
2344  *
2345  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
2346  *       DateTime tag and page 36 for the DateTimeOriginal and
2347  *       DateTimeDigitized tags.
2348  */
2349 define( 'TS_EXIF', 5 );
2350
2351 /**
2352  * Oracle format time.
2353  */
2354 define( 'TS_ORACLE', 6 );
2355
2356 /**
2357  * Postgres format time.
2358  */
2359 define( 'TS_POSTGRES', 7 );
2360
2361 /**
2362  * DB2 format time
2363  */
2364 define( 'TS_DB2', 8 );
2365
2366 /**
2367  * ISO 8601 basic format with no timezone: 19860209T200000Z.  This is used by ResourceLoader
2368  */
2369 define( 'TS_ISO_8601_BASIC', 9 );
2370
2371 /**
2372  * Get a timestamp string in one of various formats
2373  *
2374  * @param $outputtype Mixed: A timestamp in one of the supported formats, the
2375  *                    function will autodetect which format is supplied and act
2376  *                    accordingly.
2377  * @param $ts Mixed: the timestamp to convert or 0 for the current timestamp
2378  * @return Mixed: String / false The same date in the format specified in $outputtype or false
2379  */
2380 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
2381         $uts = 0;
2382         $da = array();
2383         $strtime = '';
2384
2385         if ( !$ts ) { // We want to catch 0, '', null... but not date strings starting with a letter.
2386                 $uts = time();
2387                 $strtime = "@$uts";
2388         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2389                 # TS_DB
2390         } elseif ( preg_match( '/^(\d{4}):(\d\d):(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2391                 # TS_EXIF
2392         } elseif ( preg_match( '/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/D', $ts, $da ) ) {
2393                 # TS_MW
2394         } elseif ( preg_match( '/^-?\d{1,13}$/D', $ts ) ) {
2395                 # TS_UNIX
2396                 $uts = $ts;
2397                 $strtime = "@$ts"; // http://php.net/manual/en/datetime.formats.compound.php
2398         } elseif ( preg_match( '/^\d{2}-\d{2}-\d{4} \d{2}:\d{2}:\d{2}.\d{6}$/', $ts ) ) {
2399                 # TS_ORACLE // session altered to DD-MM-YYYY HH24:MI:SS.FF6
2400                 $strtime = preg_replace( '/(\d\d)\.(\d\d)\.(\d\d)(\.(\d+))?/', "$1:$2:$3",
2401                                 str_replace( '+00:00', 'UTC', $ts ) );
2402         } elseif ( preg_match( '/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2403                 # TS_ISO_8601
2404         } elseif ( preg_match( '/^(\d{4})(\d{2})(\d{2})T(\d{2})(\d{2})(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2405                 #TS_ISO_8601_BASIC
2406         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d*[\+\- ](\d\d)$/', $ts, $da ) ) {
2407                 # TS_POSTGRES
2408         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d* GMT$/', $ts, $da ) ) {
2409                 # TS_POSTGRES
2410         } elseif (preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.\d\d\d$/', $ts, $da ) ) {
2411                 # TS_DB2
2412         } elseif ( preg_match( '/^[ \t\r\n]*([A-Z][a-z]{2},[ \t\r\n]*)?' . # Day of week
2413                                                         '\d\d?[ \t\r\n]*[A-Z][a-z]{2}[ \t\r\n]*\d{2}(?:\d{2})?' .  # dd Mon yyyy
2414                                                         '[ \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
2415                 # TS_RFC2822, accepting a trailing comment. See http://www.squid-cache.org/mail-archive/squid-users/200307/0122.html / r77171
2416                 # The regex is a superset of rfc2822 for readability
2417                 $strtime = strtok( $ts, ';' );
2418         } 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 ) ) {
2419                 # TS_RFC850
2420                 $strtime = $ts;
2421         } 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 ) ) {
2422                 # asctime
2423                 $strtime = $ts;
2424         } else {
2425                 # Bogus value...
2426                 wfDebug("wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n");
2427
2428                 return false;
2429         }
2430
2431         static $formats = array(
2432                 TS_UNIX => 'U',
2433                 TS_MW => 'YmdHis',
2434                 TS_DB => 'Y-m-d H:i:s',
2435                 TS_ISO_8601 => 'Y-m-d\TH:i:s\Z',
2436                 TS_ISO_8601_BASIC => 'Ymd\THis\Z',
2437                 TS_EXIF => 'Y:m:d H:i:s', // This shouldn't ever be used, but is included for completeness
2438                 TS_RFC2822 => 'D, d M Y H:i:s',
2439                 TS_ORACLE => 'd-m-Y H:i:s.000000', // Was 'd-M-y h.i.s A' . ' +00:00' before r51500
2440                 TS_POSTGRES => 'Y-m-d H:i:s',
2441                 TS_DB2 => 'Y-m-d H:i:s',
2442         );
2443
2444         if ( !isset( $formats[$outputtype] ) ) {
2445                 throw new MWException( 'wfTimestamp() called with illegal output type.' );
2446         }
2447
2448         if ( function_exists( "date_create" ) ) {
2449                 if ( count( $da ) ) {
2450                         $ds = sprintf("%04d-%02d-%02dT%02d:%02d:%02d.00+00:00",
2451                                 (int)$da[1], (int)$da[2], (int)$da[3],
2452                                 (int)$da[4], (int)$da[5], (int)$da[6]);
2453
2454                         $d = date_create( $ds, new DateTimeZone( 'GMT' ) );
2455                 } elseif ( $strtime ) {
2456                         $d = date_create( $strtime, new DateTimeZone( 'GMT' ) );
2457                 } else {
2458                         return false;
2459                 }
2460
2461                 if ( !$d ) {
2462                         wfDebug("wfTimestamp() fed bogus time value: $outputtype; $ts\n");
2463                         return false;
2464                 }
2465
2466                 $output = $d->format( $formats[$outputtype] );
2467         } else {
2468                 if ( count( $da ) ) {
2469                         // Warning! gmmktime() acts oddly if the month or day is set to 0
2470                         // We may want to handle that explicitly at some point
2471                         $uts = gmmktime( (int)$da[4], (int)$da[5], (int)$da[6],
2472                                 (int)$da[2], (int)$da[3], (int)$da[1] );
2473                 } elseif ( $strtime ) {
2474                         $uts = strtotime( $strtime );
2475                 }
2476
2477                 if ( $uts === false ) {
2478                         wfDebug("wfTimestamp() can't parse the timestamp (non 32-bit time? Update php): $outputtype; $ts\n");
2479                         return false;
2480                 }
2481
2482                 if ( TS_UNIX == $outputtype ) {
2483                         return $uts;
2484                 }
2485                 $output = gmdate( $formats[$outputtype], $uts );
2486         }
2487
2488         if ( ( $outputtype == TS_RFC2822 ) || ( $outputtype == TS_POSTGRES ) ) {
2489                 $output .= ' GMT';
2490         }
2491
2492         return $output;
2493 }
2494
2495 /**
2496  * Return a formatted timestamp, or null if input is null.
2497  * For dealing with nullable timestamp columns in the database.
2498  *
2499  * @param $outputtype Integer
2500  * @param $ts String
2501  * @return String
2502  */
2503 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2504         if( is_null( $ts ) ) {
2505                 return null;
2506         } else {
2507                 return wfTimestamp( $outputtype, $ts );
2508         }
2509 }
2510
2511 /**
2512  * Convenience function; returns MediaWiki timestamp for the present time.
2513  *
2514  * @return string
2515  */
2516 function wfTimestampNow() {
2517         # return NOW
2518         return wfTimestamp( TS_MW, time() );
2519 }
2520
2521 /**
2522  * Check if the operating system is Windows
2523  *
2524  * @return Bool: true if it's Windows, False otherwise.
2525  */
2526 function wfIsWindows() {
2527         static $isWindows = null;
2528         if ( $isWindows === null ) {
2529                 $isWindows = substr( php_uname(), 0, 7 ) == 'Windows';
2530         }
2531         return $isWindows;
2532 }
2533
2534 /**
2535  * Check if we are running under HipHop
2536  *
2537  * @return Bool
2538  */
2539 function wfIsHipHop() {
2540         return function_exists( 'hphp_thread_set_warmup_enabled' );
2541 }
2542
2543 /**
2544  * Swap two variables
2545  *
2546  * @param $x Mixed
2547  * @param $y Mixed
2548  */
2549 function swap( &$x, &$y ) {
2550         $z = $x;
2551         $x = $y;
2552         $y = $z;
2553 }
2554
2555 /**
2556  * Tries to get the system directory for temporary files. The TMPDIR, TMP, and
2557  * TEMP environment variables are then checked in sequence, and if none are set
2558  * try sys_get_temp_dir() for PHP >= 5.2.1. All else fails, return /tmp for Unix
2559  * or C:\Windows\Temp for Windows and hope for the best.
2560  * It is common to call it with tempnam().
2561  *
2562  * NOTE: When possible, use instead the tmpfile() function to create
2563  * temporary files to avoid race conditions on file creation, etc.
2564  *
2565  * @return String
2566  */
2567 function wfTempDir() {
2568         foreach( array( 'TMPDIR', 'TMP', 'TEMP' ) as $var ) {
2569                 $tmp = getenv( $var );
2570                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
2571                         return $tmp;
2572                 }
2573         }
2574         if( function_exists( 'sys_get_temp_dir' ) ) {
2575                 return sys_get_temp_dir();
2576         }
2577         # Usual defaults
2578         return wfIsWindows() ? 'C:\Windows\Temp' : '/tmp';
2579 }
2580
2581 /**
2582  * Make directory, and make all parent directories if they don't exist
2583  *
2584  * @param $dir String: full path to directory to create
2585  * @param $mode Integer: chmod value to use, default is $wgDirectoryMode
2586  * @param $caller String: optional caller param for debugging.
2587  * @return bool
2588  */
2589 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2590         global $wgDirectoryMode;
2591
2592         if ( FileBackend::isStoragePath( $dir ) ) { // sanity
2593                 throw new MWException( __FUNCTION__ . " given storage path `$dir`.");
2594         }
2595
2596         if ( !is_null( $caller ) ) {
2597                 wfDebug( "$caller: called wfMkdirParents($dir)\n" );
2598         }
2599
2600         if( strval( $dir ) === '' || file_exists( $dir ) ) {
2601                 return true;
2602         }
2603
2604         $dir = str_replace( array( '\\', '/' ), DIRECTORY_SEPARATOR, $dir );
2605
2606         if ( is_null( $mode ) ) {
2607                 $mode = $wgDirectoryMode;
2608         }
2609
2610         // Turn off the normal warning, we're doing our own below
2611         wfSuppressWarnings();
2612         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2613         wfRestoreWarnings();
2614
2615         if( !$ok ) {
2616                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2617                 trigger_error( __FUNCTION__ . ": failed to mkdir \"$dir\" mode $mode", E_USER_WARNING );
2618         }
2619         return $ok;
2620 }
2621
2622 /**
2623  * Remove a directory and all its content.
2624  * Does not hide error.
2625  */
2626 function wfRecursiveRemoveDir( $dir ) {
2627         wfDebug( __FUNCTION__ . "( $dir )\n" );
2628         // taken from http://de3.php.net/manual/en/function.rmdir.php#98622
2629         if ( is_dir( $dir ) ) {
2630                 $objects = scandir( $dir );
2631                 foreach ( $objects as $object ) {
2632                         if ( $object != "." && $object != ".." ) {
2633                                 if ( filetype( $dir . '/' . $object ) == "dir" ) {
2634                                         wfRecursiveRemoveDir( $dir . '/' . $object );
2635                                 } else {
2636                                         unlink( $dir . '/' . $object );
2637                                 }
2638                         }
2639                 }
2640                 reset( $objects );
2641                 rmdir( $dir );
2642         }
2643 }
2644
2645 /**
2646  * @param $nr Mixed: the number to format
2647  * @param $acc Integer: the number of digits after the decimal point, default 2
2648  * @param $round Boolean: whether or not to round the value, default true
2649  * @return float
2650  */
2651 function wfPercent( $nr, $acc = 2, $round = true ) {
2652         $ret = sprintf( "%.${acc}f", $nr );
2653         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2654 }
2655
2656 /**
2657  * Find out whether or not a mixed variable exists in a string
2658  *
2659  * @param $needle String
2660  * @param $str String
2661  * @param $insensitive Boolean
2662  * @return Boolean
2663  */
2664 function in_string( $needle, $str, $insensitive = false ) {
2665         $func = 'strpos';
2666         if( $insensitive ) $func = 'stripos';
2667
2668         return $func( $str, $needle ) !== false;
2669 }
2670
2671 /**
2672  * Safety wrapper around ini_get() for boolean settings.
2673  * The values returned from ini_get() are pre-normalized for settings
2674  * set via php.ini or php_flag/php_admin_flag... but *not*
2675  * for those set via php_value/php_admin_value.
2676  *
2677  * It's fairly common for people to use php_value instead of php_flag,
2678  * which can leave you with an 'off' setting giving a false positive
2679  * for code that just takes the ini_get() return value as a boolean.
2680  *
2681  * To make things extra interesting, setting via php_value accepts
2682  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2683  * Unrecognized values go false... again opposite PHP's own coercion
2684  * from string to bool.
2685  *
2686  * Luckily, 'properly' set settings will always come back as '0' or '1',
2687  * so we only have to worry about them and the 'improper' settings.
2688  *
2689  * I frickin' hate PHP... :P
2690  *
2691  * @param $setting String
2692  * @return Bool
2693  */
2694 function wfIniGetBool( $setting ) {
2695         $val = ini_get( $setting );
2696         // 'on' and 'true' can't have whitespace around them, but '1' can.
2697         return strtolower( $val ) == 'on'
2698                 || strtolower( $val ) == 'true'
2699                 || strtolower( $val ) == 'yes'
2700                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2701 }
2702
2703 /**
2704  * Wrapper function for PHP's dl(). This doesn't work in most situations from
2705  * PHP 5.3 onward, and is usually disabled in shared environments anyway.
2706  *
2707  * @param $extension String A PHP extension. The file suffix (.so or .dll)
2708  *                          should be omitted
2709  * @param $fileName String Name of the library, if not $extension.suffix
2710  * @return Bool - Whether or not the extension is loaded
2711  */
2712 function wfDl( $extension, $fileName = null ) {
2713         if( extension_loaded( $extension ) ) {
2714                 return true;
2715         }
2716
2717         $canDl = false;
2718         $sapi = php_sapi_name();
2719         if( version_compare( PHP_VERSION, '5.3.0', '<' ) ||
2720                 $sapi == 'cli' || $sapi == 'cgi' || $sapi == 'embed' )
2721         {
2722                 $canDl = ( function_exists( 'dl' ) && is_callable( 'dl' )
2723                 && wfIniGetBool( 'enable_dl' ) && !wfIniGetBool( 'safe_mode' ) );
2724         }
2725
2726         if( $canDl ) {
2727                 $fileName = $fileName ? $fileName : $extension;
2728                 if( wfIsWindows() ) {
2729                         $fileName = 'php_' . $fileName;
2730                 }
2731                 wfSuppressWarnings();
2732                 dl( $fileName . '.' . PHP_SHLIB_SUFFIX );
2733                 wfRestoreWarnings();
2734         }
2735         return extension_loaded( $extension );
2736 }
2737
2738 /**
2739  * Windows-compatible version of escapeshellarg()
2740  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
2741  * function puts single quotes in regardless of OS.
2742  *
2743  * Also fixes the locale problems on Linux in PHP 5.2.6+ (bug backported to
2744  * earlier distro releases of PHP)
2745  *
2746  * @param varargs
2747  * @return String
2748  */
2749 function wfEscapeShellArg( ) {
2750         wfInitShellLocale();
2751
2752         $args = func_get_args();
2753         $first = true;
2754         $retVal = '';
2755         foreach ( $args as $arg ) {
2756                 if ( !$first ) {
2757                         $retVal .= ' ';
2758                 } else {
2759                         $first = false;
2760                 }
2761
2762                 if ( wfIsWindows() ) {
2763                         // Escaping for an MSVC-style command line parser and CMD.EXE
2764                         // Refs:
2765                         //  * http://web.archive.org/web/20020708081031/http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
2766                         //  * http://technet.microsoft.com/en-us/library/cc723564.aspx
2767                         //  * Bug #13518
2768                         //  * CR r63214
2769                         // Double the backslashes before any double quotes. Escape the double quotes.
2770                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
2771                         $arg = '';
2772                         $iteration = 0;
2773                         foreach ( $tokens as $token ) {
2774                                 if ( $iteration % 2 == 1 ) {
2775                                         // Delimiter, a double quote preceded by zero or more slashes
2776                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
2777                                 } elseif ( $iteration % 4 == 2 ) {
2778                                         // ^ in $token will be outside quotes, need to be escaped
2779                                         $arg .= str_replace( '^', '^^', $token );
2780                                 } else { // $iteration % 4 == 0
2781                                         // ^ in $token will appear inside double quotes, so leave as is
2782                                         $arg .= $token;
2783                                 }
2784                                 $iteration++;
2785                         }
2786                         // Double the backslashes before the end of the string, because
2787                         // we will soon add a quote
2788                         $m = array();
2789                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
2790                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
2791                         }
2792
2793                         // Add surrounding quotes
2794                         $retVal .= '"' . $arg . '"';
2795                 } else {
2796                         $retVal .= escapeshellarg( $arg );
2797                 }
2798         }
2799         return $retVal;
2800 }
2801
2802 /**
2803  * Execute a shell command, with time and memory limits mirrored from the PHP
2804  * configuration if supported.
2805  * @param $cmd String Command line, properly escaped for shell.
2806  * @param &$retval null|Mixed optional, will receive the program's exit code.
2807  *                 (non-zero is usually failure)
2808  * @param $environ Array optional environment variables which should be
2809  *                 added to the executed command environment.
2810  * @return string collected stdout as a string (trailing newlines stripped)
2811  */
2812 function wfShellExec( $cmd, &$retval = null, $environ = array() ) {
2813         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize, $wgMaxShellTime;
2814
2815         static $disabled;
2816         if ( is_null( $disabled ) ) {
2817                 $disabled = false;
2818                 if( wfIniGetBool( 'safe_mode' ) ) {
2819                         wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
2820                         $disabled = 'safemode';
2821                 } else {
2822                         $functions = explode( ',', ini_get( 'disable_functions' ) );
2823                         $functions = array_map( 'trim', $functions );
2824                         $functions = array_map( 'strtolower', $functions );
2825                         if ( in_array( 'passthru', $functions ) ) {
2826                                 wfDebug( "passthru is in disabled_functions\n" );
2827                                 $disabled = 'passthru';
2828                         }
2829                 }
2830         }
2831         if ( $disabled ) {
2832                 $retval = 1;
2833                 return $disabled == 'safemode' ?
2834                         'Unable to run external programs in safe mode.' :
2835                         'Unable to run external programs, passthru() is disabled.';
2836         }
2837
2838         wfInitShellLocale();
2839
2840         $envcmd = '';
2841         foreach( $environ as $k => $v ) {
2842                 if ( wfIsWindows() ) {
2843                         /* Surrounding a set in quotes (method used by wfEscapeShellArg) makes the quotes themselves
2844                          * appear in the environment variable, so we must use carat escaping as documented in
2845                          * http://technet.microsoft.com/en-us/library/cc723564.aspx
2846                          * Note however that the quote isn't listed there, but is needed, and the parentheses
2847                          * are listed there but doesn't appear to need it.
2848                          */
2849                         $envcmd .= "set $k=" . preg_replace( '/([&|()<>^"])/', '^\\1', $v ) . '&& ';
2850                 } else {
2851                         /* Assume this is a POSIX shell, thus required to accept variable assignments before the command
2852                          * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_09_01
2853                          */
2854                         $envcmd .= "$k=" . escapeshellarg( $v ) . ' ';
2855                 }
2856         }
2857         $cmd = $envcmd . $cmd;
2858
2859         if ( wfIsWindows() ) {
2860                 if ( version_compare( PHP_VERSION, '5.3.0', '<' ) && /* Fixed in 5.3.0 :) */
2861                         ( version_compare( PHP_VERSION, '5.2.1', '>=' ) || php_uname( 's' ) == 'Windows NT' ) )
2862                 {
2863                         # Hack to work around PHP's flawed invocation of cmd.exe
2864                         # http://news.php.net/php.internals/21796
2865                         # Windows 9x doesn't accept any kind of quotes
2866                         $cmd = '"' . $cmd . '"';
2867                 }
2868         } elseif ( php_uname( 's' ) == 'Linux' ) {
2869                 $time = intval( $wgMaxShellTime );
2870                 $mem = intval( $wgMaxShellMemory );
2871                 $filesize = intval( $wgMaxShellFileSize );
2872
2873                 if ( $time > 0 && $mem > 0 ) {
2874                         $script = "$IP/bin/ulimit4.sh";
2875                         if ( is_executable( $script ) ) {
2876                                 $cmd = '/bin/bash ' . escapeshellarg( $script ) . " $time $mem $filesize " . escapeshellarg( $cmd );
2877                         }
2878                 }
2879         }
2880         wfDebug( "wfShellExec: $cmd\n" );
2881
2882         $retval = 1; // error by default?
2883         ob_start();
2884         passthru( $cmd, $retval );
2885         $output = ob_get_contents();
2886         ob_end_clean();
2887
2888         if ( $retval == 127 ) {
2889                 wfDebugLog( 'exec', "Possibly missing executable file: $cmd\n" );
2890         }
2891         return $output;
2892 }
2893
2894 /**
2895  * Workaround for http://bugs.php.net/bug.php?id=45132
2896  * escapeshellarg() destroys non-ASCII characters if LANG is not a UTF-8 locale
2897  */
2898 function wfInitShellLocale() {
2899         static $done = false;
2900         if ( $done ) {
2901                 return;
2902         }
2903         $done = true;
2904         global $wgShellLocale;
2905         if ( !wfIniGetBool( 'safe_mode' ) ) {
2906                 putenv( "LC_CTYPE=$wgShellLocale" );
2907                 setlocale( LC_CTYPE, $wgShellLocale );
2908         }
2909 }
2910
2911 /**
2912  * Generate a shell-escaped command line string to run a maintenance script.
2913  * Note that $parameters should be a flat array and an option with an argument
2914  * should consist of two consecutive items in the array (do not use "--option value").
2915  * @param $script string MediaWiki maintenance script path
2916  * @param $parameters Array Arguments and options to the script
2917  * @param $options Array Associative array of options:
2918  *              'php': The path to the php executable
2919  *              'wrapper': Path to a PHP wrapper to handle the maintenance script
2920  * @return Array
2921  */
2922 function wfShellMaintenanceCmd( $script, array $parameters = array(), array $options = array() ) {
2923         global $wgPhpCli;
2924         // Give site config file a chance to run the script in a wrapper.
2925         // The caller may likely want to call wfBasename() on $script.
2926         wfRunHooks( 'wfShellMaintenanceCmd', array( &$script, &$parameters, &$options ) );
2927         $cmd = isset( $options['php'] ) ? array( $options['php'] ) : array( $wgPhpCli );
2928         if ( isset( $options['wrapper'] ) ) {
2929                 $cmd[] = $options['wrapper'];
2930         }
2931         $cmd[] = $script;
2932         // Escape each parameter for shell
2933         return implode( " ", array_map( 'wfEscapeShellArg', array_merge( $cmd, $parameters ) ) );
2934 }
2935
2936 /**
2937  * wfMerge attempts to merge differences between three texts.
2938  * Returns true for a clean merge and false for failure or a conflict.
2939  *
2940  * @param $old String
2941  * @param $mine String
2942  * @param $yours String
2943  * @param $result String
2944  * @return Bool
2945  */
2946 function wfMerge( $old, $mine, $yours, &$result ) {
2947         global $wgDiff3;
2948
2949         # This check may also protect against code injection in
2950         # case of broken installations.
2951         wfSuppressWarnings();
2952         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
2953         wfRestoreWarnings();
2954
2955         if( !$haveDiff3 ) {
2956                 wfDebug( "diff3 not found\n" );
2957                 return false;
2958         }
2959
2960         # Make temporary files
2961         $td = wfTempDir();
2962         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
2963         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
2964         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
2965
2966         fwrite( $oldtextFile, $old );
2967         fclose( $oldtextFile );
2968         fwrite( $mytextFile, $mine );
2969         fclose( $mytextFile );
2970         fwrite( $yourtextFile, $yours );
2971         fclose( $yourtextFile );
2972
2973         # Check for a conflict
2974         $cmd = $wgDiff3 . ' -a --overlap-only ' .
2975                 wfEscapeShellArg( $mytextName ) . ' ' .
2976                 wfEscapeShellArg( $oldtextName ) . ' ' .
2977                 wfEscapeShellArg( $yourtextName );
2978         $handle = popen( $cmd, 'r' );
2979
2980         if( fgets( $handle, 1024 ) ) {
2981                 $conflict = true;
2982         } else {
2983                 $conflict = false;
2984         }
2985         pclose( $handle );
2986
2987         # Merge differences
2988         $cmd = $wgDiff3 . ' -a -e --merge ' .
2989                 wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
2990         $handle = popen( $cmd, 'r' );
2991         $result = '';
2992         do {
2993                 $data = fread( $handle, 8192 );
2994                 if ( strlen( $data ) == 0 ) {
2995                         break;
2996                 }
2997                 $result .= $data;
2998         } while ( true );
2999         pclose( $handle );
3000         unlink( $mytextName );
3001         unlink( $oldtextName );
3002         unlink( $yourtextName );
3003
3004         if ( $result === '' && $old !== '' && !$conflict ) {
3005                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
3006                 $conflict = true;
3007         }
3008         return !$conflict;
3009 }
3010
3011 /**
3012  * Returns unified plain-text diff of two texts.
3013  * Useful for machine processing of diffs.
3014  *
3015  * @param $before String: the text before the changes.
3016  * @param $after String: the text after the changes.
3017  * @param $params String: command-line options for the diff command.
3018  * @return String: unified diff of $before and $after
3019  */
3020 function wfDiff( $before, $after, $params = '-u' ) {
3021         if ( $before == $after ) {
3022                 return '';
3023         }
3024
3025         global $wgDiff;
3026         wfSuppressWarnings();
3027         $haveDiff = $wgDiff && file_exists( $wgDiff );
3028         wfRestoreWarnings();
3029
3030         # This check may also protect against code injection in
3031         # case of broken installations.
3032         if( !$haveDiff ) {
3033                 wfDebug( "diff executable not found\n" );
3034                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
3035                 $format = new UnifiedDiffFormatter();
3036                 return $format->format( $diffs );
3037         }
3038
3039         # Make temporary files
3040         $td = wfTempDir();
3041         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
3042         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
3043
3044         fwrite( $oldtextFile, $before );
3045         fclose( $oldtextFile );
3046         fwrite( $newtextFile, $after );
3047         fclose( $newtextFile );
3048
3049         // Get the diff of the two files
3050         $cmd = "$wgDiff " . $params . ' ' . wfEscapeShellArg( $oldtextName, $newtextName );
3051
3052         $h = popen( $cmd, 'r' );
3053
3054         $diff = '';
3055
3056         do {
3057                 $data = fread( $h, 8192 );
3058                 if ( strlen( $data ) == 0 ) {
3059                         break;
3060                 }
3061                 $diff .= $data;
3062         } while ( true );
3063
3064         // Clean up
3065         pclose( $h );
3066         unlink( $oldtextName );
3067         unlink( $newtextName );
3068
3069         // Kill the --- and +++ lines. They're not useful.
3070         $diff_lines = explode( "\n", $diff );
3071         if ( strpos( $diff_lines[0], '---' ) === 0 ) {
3072                 unset( $diff_lines[0] );
3073         }
3074         if ( strpos( $diff_lines[1], '+++' ) === 0 ) {
3075                 unset( $diff_lines[1] );
3076         }
3077
3078         $diff = implode( "\n", $diff_lines );
3079
3080         return $diff;
3081 }
3082
3083 /**
3084  * This function works like "use VERSION" in Perl, the program will die with a
3085  * backtrace if the current version of PHP is less than the version provided
3086  *
3087  * This is useful for extensions which due to their nature are not kept in sync
3088  * with releases, and might depend on other versions of PHP than the main code
3089  *
3090  * Note: PHP might die due to parsing errors in some cases before it ever
3091  *       manages to call this function, such is life
3092  *
3093  * @see perldoc -f use
3094  *
3095  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
3096  *                 a float
3097  */
3098 function wfUsePHP( $req_ver ) {
3099         $php_ver = PHP_VERSION;
3100
3101         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
3102                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
3103         }
3104 }
3105
3106 /**
3107  * This function works like "use VERSION" in Perl except it checks the version
3108  * of MediaWiki, the program will die with a backtrace if the current version
3109  * of MediaWiki is less than the version provided.
3110  *
3111  * This is useful for extensions which due to their nature are not kept in sync
3112  * with releases
3113  *
3114  * @see perldoc -f use
3115  *
3116  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
3117  *                 a float
3118  */
3119 function wfUseMW( $req_ver ) {
3120         global $wgVersion;
3121
3122         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
3123                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
3124         }
3125 }
3126
3127 /**
3128  * Return the final portion of a pathname.
3129  * Reimplemented because PHP5's basename() is buggy with multibyte text.
3130  * http://bugs.php.net/bug.php?id=33898
3131  *
3132  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
3133  * We'll consider it so always, as we don't want \s in our Unix paths either.
3134  *
3135  * @param $path String
3136  * @param $suffix String: to remove if present
3137  * @return String
3138  */
3139 function wfBaseName( $path, $suffix = '' ) {
3140         $encSuffix = ( $suffix == '' )
3141                 ? ''
3142                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
3143         $matches = array();
3144         if( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
3145                 return $matches[1];
3146         } else {
3147                 return '';
3148         }
3149 }
3150
3151 /**
3152  * Generate a relative path name to the given file.
3153  * May explode on non-matching case-insensitive paths,
3154  * funky symlinks, etc.
3155  *
3156  * @param $path String: absolute destination path including target filename
3157  * @param $from String: Absolute source path, directory only
3158  * @return String
3159  */
3160 function wfRelativePath( $path, $from ) {
3161         // Normalize mixed input on Windows...
3162         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
3163         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
3164
3165         // Trim trailing slashes -- fix for drive root
3166         $path = rtrim( $path, DIRECTORY_SEPARATOR );
3167         $from = rtrim( $from, DIRECTORY_SEPARATOR );
3168
3169         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
3170         $against = explode( DIRECTORY_SEPARATOR, $from );
3171
3172         if( $pieces[0] !== $against[0] ) {
3173                 // Non-matching Windows drive letters?
3174                 // Return a full path.
3175                 return $path;
3176         }
3177
3178         // Trim off common prefix
3179         while( count( $pieces ) && count( $against )
3180                 && $pieces[0] == $against[0] ) {
3181                 array_shift( $pieces );
3182                 array_shift( $against );
3183         }
3184
3185         // relative dots to bump us to the parent
3186         while( count( $against ) ) {
3187                 array_unshift( $pieces, '..' );
3188                 array_shift( $against );
3189         }
3190
3191         array_push( $pieces, wfBaseName( $path ) );
3192
3193         return implode( DIRECTORY_SEPARATOR, $pieces );
3194 }
3195
3196 /**
3197  * Do any deferred updates and clear the list
3198  *
3199  * @deprecated since 1.19
3200  * @see DeferredUpdates::doUpdate()
3201  * @param $commit string
3202  */
3203 function wfDoUpdates( $commit = '' ) {
3204         wfDeprecated( __METHOD__, '1.19' );
3205         DeferredUpdates::doUpdates( $commit );
3206 }
3207
3208 /**
3209  * Convert an arbitrarily-long digit string from one numeric base
3210  * to another, optionally zero-padding to a minimum column width.
3211  *
3212  * Supports base 2 through 36; digit values 10-36 are represented
3213  * as lowercase letters a-z. Input is case-insensitive.
3214  *
3215  * @param $input String: of digits
3216  * @param $sourceBase Integer: 2-36
3217  * @param $destBase Integer: 2-36
3218  * @param $pad Integer: 1 or greater
3219  * @param $lowercase Boolean
3220  * @return String or false on invalid input
3221  */
3222 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1, $lowercase = true ) {
3223         $input = strval( $input );
3224         if( $sourceBase < 2 ||
3225                 $sourceBase > 36 ||
3226                 $destBase < 2 ||
3227                 $destBase > 36 ||
3228                 $pad < 1 ||
3229                 $sourceBase != intval( $sourceBase ) ||
3230                 $destBase != intval( $destBase ) ||
3231                 $pad != intval( $pad ) ||
3232                 !is_string( $input ) ||
3233                 $input == '' ) {
3234                 return false;
3235         }
3236         $digitChars = ( $lowercase ) ? '0123456789abcdefghijklmnopqrstuvwxyz' : '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
3237         $inDigits = array();
3238         $outChars = '';
3239
3240         // Decode and validate input string
3241         $input = strtolower( $input );
3242         for( $i = 0; $i < strlen( $input ); $i++ ) {
3243                 $n = strpos( $digitChars, $input[$i] );
3244                 if( $n === false || $n > $sourceBase ) {
3245                         return false;
3246                 }
3247                 $inDigits[] = $n;
3248         }
3249
3250         // Iterate over the input, modulo-ing out an output digit
3251         // at a time until input is gone.
3252         while( count( $inDigits ) ) {
3253                 $work = 0;
3254                 $workDigits = array();
3255
3256                 // Long division...
3257                 foreach( $inDigits as $digit ) {
3258                         $work *= $sourceBase;
3259                         $work += $digit;
3260
3261                         if( $work < $destBase ) {
3262                                 // Gonna need to pull another digit.
3263                                 if( count( $workDigits ) ) {
3264                                         // Avoid zero-padding; this lets us find
3265                                         // the end of the input very easily when
3266                                         // length drops to zero.
3267                                         $workDigits[] = 0;
3268                                 }
3269                         } else {
3270                                 // Finally! Actual division!
3271                                 $workDigits[] = intval( $work / $destBase );
3272
3273                                 // Isn't it annoying that most programming languages
3274                                 // don't have a single divide-and-remainder operator,
3275                                 // even though the CPU implements it that way?
3276                                 $work = $work % $destBase;
3277                         }
3278                 }
3279
3280                 // All that division leaves us with a remainder,
3281                 // which is conveniently our next output digit.
3282                 $outChars .= $digitChars[$work];
3283
3284                 // And we continue!
3285                 $inDigits = $workDigits;
3286         }
3287
3288         while( strlen( $outChars ) < $pad ) {
3289                 $outChars .= '0';
3290         }
3291
3292         return strrev( $outChars );
3293 }
3294
3295 /**
3296  * Create an object with a given name and an array of construct parameters
3297  *
3298  * @param $name String
3299  * @param $p Array: parameters
3300  * @return object
3301  * @deprecated since 1.18, warnings in 1.18, removal in 1.20
3302  */
3303 function wfCreateObject( $name, $p ) {
3304         wfDeprecated( __FUNCTION__, '1.18' );
3305         return MWFunction::newObj( $name, $p );
3306 }
3307
3308 /**
3309  * @return bool
3310  */
3311 function wfHttpOnlySafe() {
3312         global $wgHttpOnlyBlacklist;
3313
3314         if( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
3315                 foreach( $wgHttpOnlyBlacklist as $regex ) {
3316                         if( preg_match( $regex, $_SERVER['HTTP_USER_AGENT'] ) ) {
3317                                 return false;
3318                         }
3319                 }
3320         }
3321
3322         return true;
3323 }
3324
3325 /**
3326  * Initialise php session
3327  *
3328  * @param $sessionId Bool
3329  */
3330 function wfSetupSession( $sessionId = false ) {
3331         global $wgSessionsInMemcached, $wgCookiePath, $wgCookieDomain,
3332                         $wgCookieSecure, $wgCookieHttpOnly, $wgSessionHandler;
3333         if( $wgSessionsInMemcached ) {
3334                 if ( !defined( 'MW_COMPILED' ) ) {
3335                         global $IP;
3336                         require_once( "$IP/includes/cache/MemcachedSessions.php" );
3337                 }
3338                 session_set_save_handler( 'memsess_open', 'memsess_close', 'memsess_read',
3339                         'memsess_write', 'memsess_destroy', 'memsess_gc' );
3340
3341                 // It's necessary to register a shutdown function to call session_write_close(),
3342                 // because by the time the request shutdown function for the session module is
3343                 // called, $wgMemc has already been destroyed. Shutdown functions registered
3344                 // this way are called before object destruction.
3345                 register_shutdown_function( 'memsess_write_close' );
3346         } elseif( $wgSessionHandler && $wgSessionHandler != ini_get( 'session.save_handler' ) ) {
3347                 # Only set this if $wgSessionHandler isn't null and session.save_handler
3348                 # hasn't already been set to the desired value (that causes errors)
3349                 ini_set( 'session.save_handler', $wgSessionHandler );
3350         }
3351         $httpOnlySafe = wfHttpOnlySafe() && $wgCookieHttpOnly;
3352         wfDebugLog( 'cookie',
3353                 'session_set_cookie_params: "' . implode( '", "',
3354                         array(
3355                                 0,
3356                                 $wgCookiePath,
3357                                 $wgCookieDomain,
3358                                 $wgCookieSecure,
3359                                 $httpOnlySafe ) ) . '"' );
3360         session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $httpOnlySafe );
3361         session_cache_limiter( 'private, must-revalidate' );
3362         if ( $sessionId ) {
3363                 session_id( $sessionId );
3364         }
3365         wfSuppressWarnings();
3366         session_start();
3367         wfRestoreWarnings();
3368 }
3369
3370 /**
3371  * Get an object from the precompiled serialized directory
3372  *
3373  * @param $name String
3374  * @return Mixed: the variable on success, false on failure
3375  */
3376 function wfGetPrecompiledData( $name ) {
3377         global $IP;
3378
3379         $file = "$IP/serialized/$name";
3380         if ( file_exists( $file ) ) {
3381                 $blob = file_get_contents( $file );
3382                 if ( $blob ) {
3383                         return unserialize( $blob );
3384                 }
3385         }
3386         return false;
3387 }
3388
3389 /**
3390  * Get a cache key
3391  *
3392  * @param varargs
3393  * @return String
3394  */
3395 function wfMemcKey( /*... */ ) {
3396         global $wgCachePrefix;
3397         $prefix = $wgCachePrefix === false ? wfWikiID() : $wgCachePrefix;
3398         $args = func_get_args();
3399         $key = $prefix . ':' . implode( ':', $args );
3400         $key = str_replace( ' ', '_', $key );
3401         return $key;
3402 }
3403
3404 /**
3405  * Get a cache key for a foreign DB
3406  *
3407  * @param $db String
3408  * @param $prefix String
3409  * @param varargs String
3410  * @return String
3411  */
3412 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
3413         $args = array_slice( func_get_args(), 2 );
3414         if ( $prefix ) {
3415                 $key = "$db-$prefix:" . implode( ':', $args );
3416         } else {
3417                 $key = $db . ':' . implode( ':', $args );
3418         }
3419         return $key;
3420 }
3421
3422 /**
3423  * Get an ASCII string identifying this wiki
3424  * This is used as a prefix in memcached keys
3425  *
3426  * @return String
3427  */
3428 function wfWikiID() {
3429         global $wgDBprefix, $wgDBname;
3430         if ( $wgDBprefix ) {
3431                 return "$wgDBname-$wgDBprefix";
3432         } else {
3433                 return $wgDBname;
3434         }
3435 }
3436
3437 /**
3438  * Split a wiki ID into DB name and table prefix
3439  *
3440  * @param $wiki String
3441  *
3442  * @return array
3443  */
3444 function wfSplitWikiID( $wiki ) {
3445         $bits = explode( '-', $wiki, 2 );
3446         if ( count( $bits ) < 2 ) {
3447                 $bits[] = '';
3448         }
3449         return $bits;
3450 }
3451
3452 /**
3453  * Get a Database object.
3454  *
3455  * @param $db Integer: index of the connection to get. May be DB_MASTER for the
3456  *            master (for write queries), DB_SLAVE for potentially lagged read
3457  *            queries, or an integer >= 0 for a particular server.
3458  *
3459  * @param $groups Mixed: query groups. An array of group names that this query
3460  *                belongs to. May contain a single string if the query is only
3461  *                in one group.
3462  *
3463  * @param $wiki String: the wiki ID, or false for the current wiki
3464  *
3465  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
3466  * will always return the same object, unless the underlying connection or load
3467  * balancer is manually destroyed.
3468  *
3469  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
3470  * updater to ensure that a proper database is being updated.
3471  *
3472  * @return DatabaseBase
3473  */
3474 function &wfGetDB( $db, $groups = array(), $wiki = false ) {
3475         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
3476 }
3477
3478 /**
3479  * Get a load balancer object.
3480  *
3481  * @param $wiki String: wiki ID, or false for the current wiki
3482  * @return LoadBalancer
3483  */
3484 function wfGetLB( $wiki = false ) {
3485         return wfGetLBFactory()->getMainLB( $wiki );
3486 }
3487
3488 /**
3489  * Get the load balancer factory object
3490  *
3491  * @return LBFactory
3492  */
3493 function &wfGetLBFactory() {
3494         return LBFactory::singleton();
3495 }
3496
3497 /**
3498  * Find a file.
3499  * Shortcut for RepoGroup::singleton()->findFile()
3500  *
3501  * @param $title String or Title object
3502  * @param $options array Associative array of options:
3503  *     time:           requested time for an archived image, or false for the
3504  *                     current version. An image object will be returned which was
3505  *                     created at the specified time.
3506  *
3507  *     ignoreRedirect: If true, do not follow file redirects
3508  *
3509  *     private:        If true, return restricted (deleted) files if the current
3510  *                     user is allowed to view them. Otherwise, such files will not
3511  *                     be found.
3512  *
3513  *     bypassCache:    If true, do not use the process-local cache of File objects
3514  *
3515  * @return File, or false if the file does not exist
3516  */
3517 function wfFindFile( $title, $options = array() ) {
3518         return RepoGroup::singleton()->findFile( $title, $options );
3519 }
3520
3521 /**
3522  * Get an object referring to a locally registered file.
3523  * Returns a valid placeholder object if the file does not exist.
3524  *
3525  * @param $title Title|String
3526  * @return File|null A File, or null if passed an invalid Title
3527  */
3528 function wfLocalFile( $title ) {
3529         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
3530 }
3531
3532 /**
3533  * Stream a file to the browser. Back-compat alias for StreamFile::stream()
3534  * @deprecated since 1.19
3535  */
3536 function wfStreamFile( $fname, $headers = array() ) {
3537         wfDeprecated( __FUNCTION__, '1.19' );
3538         StreamFile::stream( $fname, $headers );
3539 }
3540
3541 /**
3542  * Should low-performance queries be disabled?
3543  *
3544  * @return Boolean
3545  * @codeCoverageIgnore
3546  */
3547 function wfQueriesMustScale() {
3548         global $wgMiserMode;
3549         return $wgMiserMode
3550                 || ( SiteStats::pages() > 100000
3551                 && SiteStats::edits() > 1000000
3552                 && SiteStats::users() > 10000 );
3553 }
3554
3555 /**
3556  * Get the path to a specified script file, respecting file
3557  * extensions; this is a wrapper around $wgScriptExtension etc.
3558  *
3559  * @param $script String: script filename, sans extension
3560  * @return String
3561  */
3562 function wfScript( $script = 'index' ) {
3563         global $wgScriptPath, $wgScriptExtension;
3564         return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
3565 }
3566
3567 /**
3568  * Get the script URL.
3569  *
3570  * @return string script URL
3571  */
3572 function wfGetScriptUrl() {
3573         if( isset( $_SERVER['SCRIPT_NAME'] ) ) {
3574                 #
3575                 # as it was called, minus the query string.
3576                 #
3577                 # Some sites use Apache rewrite rules to handle subdomains,
3578                 # and have PHP set up in a weird way that causes PHP_SELF
3579                 # to contain the rewritten URL instead of the one that the
3580                 # outside world sees.
3581                 #
3582                 # If in this mode, use SCRIPT_URL instead, which mod_rewrite
3583                 # provides containing the "before" URL.
3584                 return $_SERVER['SCRIPT_NAME'];
3585         } else {
3586                 return $_SERVER['URL'];
3587         }
3588 }
3589
3590 /**
3591  * Convenience function converts boolean values into "true"
3592  * or "false" (string) values
3593  *
3594  * @param $value Boolean
3595  * @return String
3596  */
3597 function wfBoolToStr( $value ) {
3598         return $value ? 'true' : 'false';
3599 }
3600
3601 /**
3602  * Load an extension messages file
3603  *
3604  * @deprecated since 1.16, warnings in 1.18, remove in 1.20
3605  * @codeCoverageIgnore
3606  */
3607 function wfLoadExtensionMessages() {
3608         wfDeprecated( __FUNCTION__, '1.16' );
3609 }
3610
3611 /**
3612  * Get a platform-independent path to the null file, e.g. /dev/null
3613  *
3614  * @return string
3615  */
3616 function wfGetNull() {
3617         return wfIsWindows()
3618                 ? 'NUL'
3619                 : '/dev/null';
3620 }
3621
3622 /**
3623  * Modern version of wfWaitForSlaves(). Instead of looking at replication lag
3624  * and waiting for it to go down, this waits for the slaves to catch up to the
3625  * master position. Use this when updating very large numbers of rows, as
3626  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
3627  * a no-op if there are no slaves.
3628  *
3629  * @param $maxLag Integer (deprecated)
3630  * @param $wiki mixed Wiki identifier accepted by wfGetLB
3631  */
3632 function wfWaitForSlaves( $maxLag = false, $wiki = false ) {
3633         $lb = wfGetLB( $wiki );
3634         // bug 27975 - Don't try to wait for slaves if there are none
3635         // Prevents permission error when getting master position
3636         if ( $lb->getServerCount() > 1 ) {
3637                 $dbw = $lb->getConnection( DB_MASTER );
3638                 $pos = $dbw->getMasterPos();
3639                 $lb->waitForAll( $pos );
3640         }
3641 }
3642
3643 /**
3644  * Used to be used for outputting text in the installer/updater
3645  * @deprecated since 1.18, warnings in 1.18, remove in 1.20
3646  */
3647 function wfOut( $s ) {
3648         wfDeprecated( __FUNCTION__, '1.18' );
3649         global $wgCommandLineMode;
3650         if ( $wgCommandLineMode ) {
3651                 echo $s;
3652         } else {
3653                 echo htmlspecialchars( $s );
3654         }
3655         flush();
3656 }
3657
3658 /**
3659  * Count down from $n to zero on the terminal, with a one-second pause
3660  * between showing each number. For use in command-line scripts.
3661  * @codeCoverageIgnore
3662  * @param $n int
3663  */
3664 function wfCountDown( $n ) {
3665         for ( $i = $n; $i >= 0; $i-- ) {
3666                 if ( $i != $n ) {
3667                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3668                 }
3669                 echo $i;
3670                 flush();
3671                 if ( $i ) {
3672                         sleep( 1 );
3673                 }
3674         }
3675         echo "\n";
3676 }
3677
3678 /**
3679  * Generate a random 32-character hexadecimal token.
3680  * @param $salt Mixed: some sort of salt, if necessary, to add to random
3681  *              characters before hashing.
3682  * @return string
3683  * @codeCoverageIgnore
3684  */
3685 function wfGenerateToken( $salt = '' ) {
3686         $salt = serialize( $salt );
3687         return md5( mt_rand( 0, 0x7fffffff ) . $salt );
3688 }
3689
3690 /**
3691  * Replace all invalid characters with -
3692  *
3693  * @param $name Mixed: filename to process
3694  * @return String
3695  */
3696 function wfStripIllegalFilenameChars( $name ) {
3697         global $wgIllegalFileChars;
3698         $name = wfBaseName( $name );
3699         $name = preg_replace(
3700                 "/[^" . Title::legalChars() . "]" .
3701                         ( $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '' ) .
3702                         "/",
3703                 '-',
3704                 $name
3705         );
3706         return $name;
3707 }
3708
3709 /**
3710  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit;
3711  *
3712  * @return Integer value memory was set to.
3713  */
3714 function wfMemoryLimit() {
3715         global $wgMemoryLimit;
3716         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3717         if( $memlimit != -1 ) {
3718                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3719                 if( $conflimit == -1 ) {
3720                         wfDebug( "Removing PHP's memory limit\n" );
3721                         wfSuppressWarnings();
3722                         ini_set( 'memory_limit', $conflimit );
3723                         wfRestoreWarnings();
3724                         return $conflimit;
3725                 } elseif ( $conflimit > $memlimit ) {
3726                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3727                         wfSuppressWarnings();
3728                         ini_set( 'memory_limit', $conflimit );
3729                         wfRestoreWarnings();
3730                         return $conflimit;
3731                 }
3732         }
3733         return $memlimit;
3734 }
3735
3736 /**
3737  * Converts shorthand byte notation to integer form
3738  *
3739  * @param $string String
3740  * @return Integer
3741  */
3742 function wfShorthandToInteger( $string = '' ) {
3743         $string = trim( $string );
3744         if( $string === '' ) {
3745                 return -1;
3746         }
3747         $last = $string[strlen( $string ) - 1];
3748         $val = intval( $string );
3749         switch( $last ) {
3750                 case 'g':
3751                 case 'G':
3752                         $val *= 1024;
3753                         // break intentionally missing
3754                 case 'm':
3755                 case 'M':
3756                         $val *= 1024;
3757                         // break intentionally missing
3758                 case 'k':
3759                 case 'K':
3760                         $val *= 1024;
3761         }
3762
3763         return $val;
3764 }
3765
3766 /**
3767  * Get the normalised IETF language tag
3768  * See unit test for examples.
3769  *
3770  * @param $code String: The language code.
3771  * @return String: The language code which complying with BCP 47 standards.
3772  */
3773 function wfBCP47( $code ) {
3774         $codeSegment = explode( '-', $code );
3775         $codeBCP = array();
3776         foreach ( $codeSegment as $segNo => $seg ) {
3777                 if ( count( $codeSegment ) > 0 ) {
3778                         // when previous segment is x, it is a private segment and should be lc
3779                         if( $segNo > 0 && strtolower( $codeSegment[( $segNo - 1 )] ) == 'x' ) {
3780                                 $codeBCP[$segNo] = strtolower( $seg );
3781                         // ISO 3166 country code
3782                         } elseif ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3783                                 $codeBCP[$segNo] = strtoupper( $seg );
3784                         // ISO 15924 script code
3785                         } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3786                                 $codeBCP[$segNo] = ucfirst( strtolower( $seg ) );
3787                         // Use lowercase for other cases
3788                         } else {
3789                                 $codeBCP[$segNo] = strtolower( $seg );
3790                         }
3791                 } else {
3792                 // Use lowercase for single segment
3793                         $codeBCP[$segNo] = strtolower( $seg );
3794                 }
3795         }
3796         $langCode = implode( '-', $codeBCP );
3797         return $langCode;
3798 }
3799
3800 /**
3801  * Get a cache object.
3802  *
3803  * @param $inputType integer Cache type, one the the CACHE_* constants.
3804  * @return BagOStuff
3805  */
3806 function wfGetCache( $inputType ) {
3807         return ObjectCache::getInstance( $inputType );
3808 }
3809
3810 /**
3811  * Get the main cache object
3812  *
3813  * @return BagOStuff
3814  */
3815 function wfGetMainCache() {
3816         global $wgMainCacheType;
3817         return ObjectCache::getInstance( $wgMainCacheType );
3818 }
3819
3820 /**
3821  * Get the cache object used by the message cache
3822  *
3823  * @return BagOStuff
3824  */
3825 function wfGetMessageCacheStorage() {
3826         global $wgMessageCacheType;
3827         return ObjectCache::getInstance( $wgMessageCacheType );
3828 }
3829
3830 /**
3831  * Get the cache object used by the parser cache
3832  *
3833  * @return BagOStuff
3834  */
3835 function wfGetParserCacheStorage() {
3836         global $wgParserCacheType;
3837         return ObjectCache::getInstance( $wgParserCacheType );
3838 }
3839
3840 /**
3841  * Call hook functions defined in $wgHooks
3842  *
3843  * @param $event String: event name
3844  * @param $args Array: parameters passed to hook functions
3845  * @return Boolean True if no handler aborted the hook
3846  */
3847 function wfRunHooks( $event, $args = array() ) {
3848         return Hooks::run( $event, $args );
3849 }
3850
3851 /**
3852  * Wrapper around php's unpack.
3853  *
3854  * @param $format String: The format string (See php's docs)
3855  * @param $data: A binary string of binary data
3856  * @param $length integer or false: The minimun length of $data. This is to
3857  *      prevent reading beyond the end of $data. false to disable the check.
3858  *
3859  * Also be careful when using this function to read unsigned 32 bit integer
3860  * because php might make it negative.
3861  *
3862  * @throws MWException if $data not long enough, or if unpack fails
3863  * @return array Associative array of the extracted data
3864  */
3865 function wfUnpack( $format, $data, $length=false ) {
3866         if ( $length !== false ) {
3867                 $realLen = strlen( $data );
3868                 if ( $realLen < $length ) {
3869                         throw new MWException( "Tried to use wfUnpack on a "
3870                                 . "string of length $realLen, but needed one "
3871                                 . "of at least length $length."
3872                         );
3873                 }
3874         }
3875
3876         wfSuppressWarnings();
3877         $result = unpack( $format, $data );
3878         wfRestoreWarnings();
3879
3880         if ( $result === false ) {
3881                 // If it cannot extract the packed data.
3882                 throw new MWException( "unpack could not unpack binary data" );
3883         }
3884         return $result;
3885 }