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