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  */
  85 function wfArrayDiff2( $a, $b ) {
  86         return array_udiff( $a, $b, 'wfArrayDiff2_cmp' );
  87 }
  88
  89 /**
  90  * @param $a
  91  * @param $b
  92  * @return int
  93  */
  94 function wfArrayDiff2_cmp( $a, $b ) {
  95         if ( !is_array( $a ) ) {
  96                 return strcmp( $a, $b );
  97         } elseif ( count( $a ) !== count( $b ) ) {
  98                 return count( $a ) < count( $b ) ? -1 : 1;
  99         } else {
 100                 reset( $a );
 101                 reset( $b );
 102                 while( ( list( , $valueA ) = each( $a ) ) && ( list( , $valueB ) = each( $b ) ) ) {
 103                         $cmp = strcmp( $valueA, $valueB );
 104                         if ( $cmp !== 0 ) {
 105                                 return $cmp;
 106                         }
 107                 }
 108                 return 0;
 109         }
 110 }
 111
 112 /**
 113  * Array lookup
 114  * Returns an array where the values in the first array are replaced by the
 115  * values in the second array with the corresponding keys
 116  *
 117  * @param $a Array
 118  * @param $b Array
 119  * @return array
 120  */
 121 function wfArrayLookup( $a, $b ) {
 122         return array_flip( array_intersect( array_flip( $a ), array_keys( $b ) ) );
 123 }
 124
 125 /**
 126  * Appends to second array if $value differs from that in $default
 127  *
 128  * @param $key String|Int
 129  * @param $value Mixed
 130  * @param $default Mixed
 131  * @param $changed Array to alter
 132  */
 133 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
 134         if ( is_null( $changed ) ) {
 135                 throw new MWException( 'GlobalFunctions::wfAppendToArrayIfNotDefault got null' );
 136         }
 137         if ( $default[$key] !== $value ) {
 138                 $changed[$key] = $value;
 139         }
 140 }
 141
 142 /**
 143  * Backwards array plus for people who haven't bothered to read the PHP manual
 144  * XXX: will not darn your socks for you.
 145  *
 146  * @param $array1 Array
 147  * @param [$array2, [...]] Arrays
 148  * @return Array
 149  */
 150 function wfArrayMerge( $array1/* ... */ ) {
 151         $args = func_get_args();
 152         $args = array_reverse( $args, true );
 153         $out = array();
 154         foreach ( $args as $arg ) {
 155                 $out += $arg;
 156         }
 157         return $out;
 158 }
 159
 160 /**
 161  * Merge arrays in the style of getUserPermissionsErrors, with duplicate removal
 162  * e.g.
 163  *      wfMergeErrorArrays(
 164  *              array( array( 'x' ) ),
 165  *              array( array( 'x', '2' ) ),
 166  *              array( array( 'x' ) ),
 167  *              array( array( 'y') )
 168  *      );
 169  * returns:
 170  *              array(
 171  *              array( 'x', '2' ),
 172  *              array( 'x' ),
 173  *              array( 'y' )
 174  *      )
 175  * @param varargs
 176  * @return Array
 177  */
 178 function wfMergeErrorArrays( /*...*/ ) {
 179         $args = func_get_args();
 180         $out = array();
 181         foreach ( $args as $errors ) {
 182                 foreach ( $errors as $params ) {
 183                         # @todo FIXME: Sometimes get nested arrays for $params,
 184                         # which leads to E_NOTICEs
 185                         $spec = implode( "\t", $params );
 186                         $out[$spec] = $params;
 187                 }
 188         }
 189         return array_values( $out );
 190 }
 191
 192 /**
 193  * Insert array into another array after the specified *KEY*
 194  *
 195  * @param $array Array: The array.
 196  * @param $insert Array: The array to insert.
 197  * @param $after Mixed: The key to insert after
 198  * @return Array
 199  */
 200 function wfArrayInsertAfter( $array, $insert, $after ) {
 201         // Find the offset of the element to insert after.
 202         $keys = array_keys( $array );
 203         $offsetByKey = array_flip( $keys );
 204
 205         $offset = $offsetByKey[$after];
 206
 207         // Insert at the specified offset
 208         $before = array_slice( $array, 0, $offset + 1, true );
 209         $after = array_slice( $array, $offset + 1, count( $array ) - $offset, true );
 210
 211         $output = $before + $insert + $after;
 212
 213         return $output;
 214 }
 215
 216 /**
 217  * Recursively converts the parameter (an object) to an array with the same data
 218  *
 219  * @param $objOrArray Object|Array
 220  * @param $recursive Bool
 221  * @return Array
 222  */
 223 function wfObjectToArray( $objOrArray, $recursive = true ) {
 224         $array = array();
 225         if( is_object( $objOrArray ) ) {
 226                 $objOrArray = get_object_vars( $objOrArray );
 227         }
 228         foreach ( $objOrArray as $key => $value ) {
 229                 if ( $recursive && ( is_object( $value ) || is_array( $value ) ) ) {
 230                         $value = wfObjectToArray( $value );
 231                 }
 232
 233                 $array[$key] = $value;
 234         }
 235
 236         return $array;
 237 }
 238
 239 /**
 240  * Wrapper around array_map() which also taints variables
 241  *
 242  * @param  $function Callback
 243  * @param  $input Array
 244  * @return Array
 245  */
 246 function wfArrayMap( $function, $input ) {
 247         $ret = array_map( $function, $input );
 248         foreach ( $ret as $key => $value ) {
 249                 $taint = istainted( $input[$key] );
 250                 if ( $taint ) {
 251                         taint( $ret[$key], $taint );
 252                 }
 253         }
 254         return $ret;
 255 }
 256
 257 /**
 258  * Get a random decimal value between 0 and 1, in a way
 259  * not likely to give duplicate values for any realistic
 260  * number of articles.
 261  *
 262  * @return string
 263  */
 264 function wfRandom() {
 265         # The maximum random value is "only" 2^31-1, so get two random
 266         # values to reduce the chance of dupes
 267         $max = mt_getrandmax() + 1;
 268         $rand = number_format( ( mt_rand() * $max + mt_rand() )
 269                 / $max / $max, 12, '.', '' );
 270         return $rand;
 271 }
 272
 273 /**
 274  * We want some things to be included as literal characters in our title URLs
 275  * for prettiness, which urlencode encodes by default.  According to RFC 1738,
 276  * all of the following should be safe:
 277  *
 278  * ;:@&=$-_.+!*'(),
 279  *
 280  * But + is not safe because it's used to indicate a space; &= are only safe in
 281  * paths and not in queries (and we don't distinguish here); ' seems kind of
 282  * scary; and urlencode() doesn't touch -_. to begin with.  Plus, although /
 283  * is reserved, we don't care.  So the list we unescape is:
 284  *
 285  * ;:@$!*(),/
 286  *
 287  * However, IIS7 redirects fail when the url contains a colon (Bug 22709),
 288  * so no fancy : for IIS7.
 289  *
 290  * %2F in the page titles seems to fatally break for some reason.
 291  *
 292  * @param $s String:
 293  * @return string
 294 */
 295 function wfUrlencode( $s ) {
 296         static $needle;
 297         if ( is_null( $s ) ) {
 298                 $needle = null;
 299                 return;
 300         }
 301
 302         if ( is_null( $needle ) ) {
 303                 $needle = array( '%3B', '%40', '%24', '%21', '%2A', '%28', '%29', '%2C', '%2F' );
 304                 if ( !isset( $_SERVER['SERVER_SOFTWARE'] ) || ( strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/7' ) === false ) ) {
 305                         $needle[] = '%3A';
 306                 }
 307         }
 308
 309         $s = urlencode( $s );
 310         $s = str_ireplace(
 311                 $needle,
 312                 array( ';', '@', '$', '!', '*', '(', ')', ',', '/', ':' ),
 313                 $s
 314         );
 315
 316         return $s;
 317 }
 318
 319 /**
 320  * This function takes two arrays as input, and returns a CGI-style string, e.g.
 321  * "days=7&limit=100". Options in the first array override options in the second.
 322  * Options set to "" will not be output.
 323  *
 324  * @param $array1 Array ( String|Array )
 325  * @param $array2 Array ( String|Array )
 326  * @param $prefix String
 327  * @return String
 328  */
 329 function wfArrayToCGI( $array1, $array2 = null, $prefix = '' ) {
 330         if ( !is_null( $array2 ) ) {
 331                 $array1 = $array1 + $array2;
 332         }
 333
 334         $cgi = '';
 335         foreach ( $array1 as $key => $value ) {
 336                 if ( $value !== '' ) {
 337                         if ( $cgi != '' ) {
 338                                 $cgi .= '&';
 339                         }
 340                         if ( $prefix !== '' ) {
 341                                 $key = $prefix . "[$key]";
 342                         }
 343                         if ( is_array( $value ) ) {
 344                                 $firstTime = true;
 345                                 foreach ( $value as $k => $v ) {
 346                                         $cgi .= $firstTime ? '' : '&';
 347                                         if ( is_array( $v ) ) {
 348                                                 $cgi .= wfArrayToCGI( $v, null, $key . "[$k]" );
 349                                         } else {
 350                                                 $cgi .= urlencode( $key . "[$k]" ) . '=' . urlencode( $v );
 351                                         }
 352                                         $firstTime = false;
 353                                 }
 354                         } else {
 355                                 if ( is_object( $value ) ) {
 356                                         $value = $value->__toString();
 357                                 }
 358                                 $cgi .= urlencode( $key ) . '=' . urlencode( $value );
 359                         }
 360                 }
 361         }
 362         return $cgi;
 363 }
 364
 365 /**
 366  * This is the logical opposite of wfArrayToCGI(): it accepts a query string as
 367  * its argument and returns the same string in array form.  This allows compa-
 368  * tibility with legacy functions that accept raw query strings instead of nice
 369  * arrays.  Of course, keys and values are urldecode()d.  Don't try passing in-
 370  * valid query strings, or it will explode.
 371  *
 372  * @param $query String: query string
 373  * @return array Array version of input
 374  */
 375 function wfCgiToArray( $query ) {
 376         if ( isset( $query[0] ) && $query[0] == '?' ) {
 377                 $query = substr( $query, 1 );
 378         }
 379         $bits = explode( '&', $query );
 380         $ret = array();
 381         foreach ( $bits as $bit ) {
 382                 if ( $bit === '' ) {
 383                         continue;
 384                 }
 385                 list( $key, $value ) = explode( '=', $bit );
 386                 $key = urldecode( $key );
 387                 $value = urldecode( $value );
 388                 if ( strpos( $key, '[' ) !== false ) {
 389                         $keys = array_reverse( explode( '[', $key ) );
 390                         $key = array_pop( $keys );
 391                         $temp = $value;
 392                         foreach ( $keys as $k ) {
 393                                 $k = substr( $k, 0, -1 );
 394                                 $temp = array( $k => $temp );
 395                         }
 396                         if ( isset( $ret[$key] ) ) {
 397                                 $ret[$key] = array_merge( $ret[$key], $temp );
 398                         } else {
 399                                 $ret[$key] = $temp;
 400                         }
 401                 } else {
 402                         $ret[$key] = $value;
 403                 }
 404         }
 405         return $ret;
 406 }
 407
 408 /**
 409  * Append a query string to an existing URL, which may or may not already
 410  * have query string parameters already. If so, they will be combined.
 411  *
 412  * @param $url String
 413  * @param $query Mixed: string or associative array
 414  * @return string
 415  */
 416 function wfAppendQuery( $url, $query ) {
 417         if ( is_array( $query ) ) {
 418                 $query = wfArrayToCGI( $query );
 419         }
 420         if( $query != '' ) {
 421                 if( false === strpos( $url, '?' ) ) {
 422                         $url .= '?';
 423                 } else {
 424                         $url .= '&';
 425                 }
 426                 $url .= $query;
 427         }
 428         return $url;
 429 }
 430
 431 /**
 432  * Expand a potentially local URL to a fully-qualified URL.  Assumes $wgServer
 433  * is correct.
 434  *
 435  * The meaning of the PROTO_* constants is as follows:
 436  * PROTO_HTTP: Output a URL starting with http://
 437  * PROTO_HTTPS: Output a URL starting with https://
 438  * PROTO_RELATIVE: Output a URL starting with // (protocol-relative URL)
 439  * PROTO_CURRENT: Output a URL starting with either http:// or https:// , depending on which protocol was used for the current incoming request
 440  * PROTO_CANONICAL: For URLs without a domain, like /w/index.php , use $wgCanonicalServer. For protocol-relative URLs, use the protocol of $wgCanonicalServer
 441  *
 442  * @todo this won't work with current-path-relative URLs
 443  * like "subdir/foo.html", etc.
 444  *
 445  * @param $url String: either fully-qualified or a local path + query
 446  * @param $defaultProto Mixed: one of the PROTO_* constants. Determines the protocol to use if $url or $wgServer is protocol-relative
 447  * @return string Fully-qualified URL
 448  */
 449 function wfExpandUrl( $url, $defaultProto = PROTO_CURRENT ) {
 450         global $wgServer, $wgCanonicalServer;
 451         $serverUrl = $defaultProto === PROTO_CANONICAL ? $wgCanonicalServer : $wgServer;
 452
 453         if ( $defaultProto === PROTO_CURRENT ) {
 454                 $defaultProto = WebRequest::detectProtocol() . '://';
 455         }
 456
 457         // Analyze $serverUrl to obtain its protocol
 458         $bits = wfParseUrl( $serverUrl );
 459         $serverHasProto = $bits && $bits['scheme'] != '';
 460
 461         if ( $defaultProto === PROTO_CANONICAL ) {
 462                 if ( $serverHasProto ) {
 463                         $defaultProto = $bits['scheme'] . '://';
 464                 } else {
 465                         // $wgCanonicalServer doesn't have a protocol. This really isn't supposed to happen
 466                         // Fall back to HTTP in this ridiculous case
 467                         $defaultProto = PROTO_HTTP;
 468                 }
 469         }
 470
 471         $defaultProtoWithoutSlashes = substr( $defaultProto, 0, -2 );
 472
 473         if( substr( $url, 0, 2 ) == '//' ) {
 474                 return $defaultProtoWithoutSlashes . $url;
 475         } elseif( substr( $url, 0, 1 ) == '/' ) {
 476                 // If $serverUrl is protocol-relative, prepend $defaultProtoWithoutSlashes, otherwise leave it alone
 477                 return ( $serverHasProto ? '' : $defaultProtoWithoutSlashes ) . $serverUrl . $url;
 478         } else {
 479                 return $url;
 480         }
 481 }
 482
 483 /**
 484  * Returns a regular expression of url protocols
 485  *
 486  * @param $includeProtocolRelative bool If false, remove '//' from the returned protocol list.
 487  *        DO NOT USE this directy, use wfUrlProtocolsWithoutProtRel() instead
 488  * @return String
 489  */
 490 function wfUrlProtocols( $includeProtocolRelative = true ) {
 491         global $wgUrlProtocols;
 492
 493         // Cache return values separately based on $includeProtocolRelative
 494         static $withProtRel = null, $withoutProtRel = null;
 495         $cachedValue = $includeProtocolRelative ? $withProtRel : $withoutProtRel;
 496         if ( !is_null( $cachedValue ) ) {
 497                 return $cachedValue;
 498         }
 499
 500         // Support old-style $wgUrlProtocols strings, for backwards compatibility
 501         // with LocalSettings files from 1.5
 502         if ( is_array( $wgUrlProtocols ) ) {
 503                 $protocols = array();
 504                 foreach ( $wgUrlProtocols as $protocol ) {
 505                         // Filter out '//' if !$includeProtocolRelative
 506                         if ( $includeProtocolRelative || $protocol !== '//' ) {
 507                                 $protocols[] = preg_quote( $protocol, '/' );
 508                         }
 509                 }
 510
 511                 $retval = implode( '|', $protocols );
 512         } else {
 513                 // Ignore $includeProtocolRelative in this case
 514                 // This case exists for pre-1.6 compatibility, and we can safely assume
 515                 // that '//' won't appear in a pre-1.6 config because protocol-relative
 516                 // URLs weren't supported until 1.18
 517                 $retval = $wgUrlProtocols;
 518         }
 519
 520         // Cache return value
 521         if ( $includeProtocolRelative ) {
 522                 $withProtRel = $retval;
 523         } else {
 524                 $withoutProtRel = $retval;
 525         }
 526         return $retval;
 527 }
 528
 529 /**
 530  * Like wfUrlProtocols(), but excludes '//' from the protocol list. Use this if
 531  * you need a regex that matches all URL protocols but does not match protocol-
 532  * relative URLs
 533  */
 534 function wfUrlProtocolsWithoutProtRel() {
 535         return wfUrlProtocols( false );
 536 }
 537
 538 /**
 539  * parse_url() work-alike, but non-broken.  Differences:
 540  *
 541  * 1) Does not raise warnings on bad URLs (just returns false)
 542  * 2) Handles protocols that don't use :// (e.g., mailto: and news: , as well as protocol-relative URLs) correctly
 543  * 3) Adds a "delimiter" element to the array, either '://', ':' or '//' (see (2))
 544  *
 545  * @param $url String: a URL to parse
 546  * @return Array: bits of the URL in an associative array, per PHP docs
 547  */
 548 function wfParseUrl( $url ) {
 549         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
 550
 551         // Protocol-relative URLs are handled really badly by parse_url(). It's so bad that the easiest
 552         // way to handle them is to just prepend 'http:' and strip the protocol out later
 553         $wasRelative = substr( $url, 0, 2 ) == '//';
 554         if ( $wasRelative ) {
 555                 $url = "http:$url";
 556         }
 557         wfSuppressWarnings();
 558         $bits = parse_url( $url );
 559         wfRestoreWarnings();
 560         // parse_url() returns an array without scheme for some invalid URLs, e.g.
 561         // parse_url("%0Ahttp://example.com") == array( 'host' => '%0Ahttp', 'path' => 'example.com' )
 562         if ( !$bits || !isset( $bits['scheme'] ) ) {
 563                 return false;
 564         }
 565
 566         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
 567         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
 568                 $bits['delimiter'] = '://';
 569         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
 570                 $bits['delimiter'] = ':';
 571                 // parse_url detects for news: and mailto: the host part of an url as path
 572                 // We have to correct this wrong detection
 573                 if ( isset( $bits['path'] ) ) {
 574                         $bits['host'] = $bits['path'];
 575                         $bits['path'] = '';
 576                 }
 577         } else {
 578                 return false;
 579         }
 580
 581         /* Provide an empty host for eg. file:/// urls (see bug 28627) */
 582         if ( !isset( $bits['host'] ) ) {
 583                 $bits['host'] = '';
 584
 585                 /* parse_url loses the third / for file:///c:/ urls (but not on variants) */
 586                 if ( substr( $bits['path'], 0, 1 ) !== '/' ) {
 587                         $bits['path'] = '/' . $bits['path'];
 588                 }
 589         }
 590
 591         // If the URL was protocol-relative, fix scheme and delimiter
 592         if ( $wasRelative ) {
 593                 $bits['scheme'] = '';
 594                 $bits['delimiter'] = '//';
 595         }
 596         return $bits;
 597 }
 598
 599 /**
 600  * Make a URL index, appropriate for the el_index field of externallinks.
 601  *
 602  * @param $url String
 603  * @return String
 604  */
 605 function wfMakeUrlIndex( $url ) {
 606         $bits = wfParseUrl( $url );
 607
 608         // Reverse the labels in the hostname, convert to lower case
 609         // For emails reverse domainpart only
 610         if ( $bits['scheme'] == 'mailto' ) {
 611                 $mailparts = explode( '@', $bits['host'], 2 );
 612                 if ( count( $mailparts ) === 2 ) {
 613                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
 614                 } else {
 615                         // No domain specified, don't mangle it
 616                         $domainpart = '';
 617                 }
 618                 $reversedHost = $domainpart . '@' . $mailparts[0];
 619         } else {
 620                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
 621         }
 622         // Add an extra dot to the end
 623         // Why? Is it in wrong place in mailto links?
 624         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
 625                 $reversedHost .= '.';
 626         }
 627         // Reconstruct the pseudo-URL
 628         $prot = $bits['scheme'];
 629         $index = $prot . $bits['delimiter'] . $reversedHost;
 630         // Leave out user and password. Add the port, path, query and fragment
 631         if ( isset( $bits['port'] ) ) {
 632                 $index .= ':' . $bits['port'];
 633         }
 634         if ( isset( $bits['path'] ) ) {
 635                 $index .= $bits['path'];
 636         } else {
 637                 $index .= '/';
 638         }
 639         if ( isset( $bits['query'] ) ) {
 640                 $index .= '?' . $bits['query'];
 641         }
 642         if ( isset( $bits['fragment'] ) ) {
 643                 $index .= '#' . $bits['fragment'];
 644         }
 645         return $index;
 646 }
 647
 648 /**
 649  * Check whether a given URL has a domain that occurs in a given set of domains
 650  * @param $url string URL
 651  * @param $domains array Array of domains (strings)
 652  * @return bool True if the host part of $url ends in one of the strings in $domains
 653  */
 654 function wfMatchesDomainList( $url, $domains ) {
 655         $bits = wfParseUrl( $url );
 656         if ( is_array( $bits ) && isset( $bits['host'] ) ) {
 657                 foreach ( (array)$domains as $domain ) {
 658                         // FIXME: This gives false positives. http://nds-nl.wikipedia.org will match nl.wikipedia.org
 659                         // We should use something that interprets dots instead
 660                         if ( substr( $bits['host'], -strlen( $domain ) ) === $domain ) {
 661                                 return true;
 662                         }
 663                 }
 664         }
 665         return false;
 666 }
 667
 668 /**
 669  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
 670  * In normal operation this is a NOP.
 671  *
 672  * Controlling globals:
 673  * $wgDebugLogFile - points to the log file
 674  * $wgProfileOnly - if set, normal debug messages will not be recorded.
 675  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
 676  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
 677  *
 678  * @param $text String
 679  * @param $logonly Bool: set true to avoid appearing in HTML when $wgDebugComments is set
 680  */
 681 function wfDebug( $text, $logonly = false ) {
 682         global $wgOut, $wgDebugLogFile, $wgDebugComments, $wgProfileOnly, $wgDebugRawPage;
 683         global $wgDebugLogPrefix, $wgShowDebug;
 684
 685         static $cache = array(); // Cache of unoutputted messages
 686         $text = wfDebugTimer() . $text;
 687
 688         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
 689                 return;
 690         }
 691
 692         if ( ( $wgDebugComments || $wgShowDebug ) && !$logonly ) {
 693                 $cache[] = $text;
 694
 695                 if ( isset( $wgOut ) && is_object( $wgOut ) ) {
 696                         // add the message and any cached messages to the output
 697                         array_map( array( $wgOut, 'debug' ), $cache );
 698                         $cache = array();
 699                 }
 700         }
 701         if ( wfRunHooks( 'Debug', array( $text, null /* no log group */ ) ) ) {
 702                 if ( $wgDebugLogFile != '' && !$wgProfileOnly ) {
 703                         # Strip unprintables; they can switch terminal modes when binary data
 704                         # gets dumped, which is pretty annoying.
 705                         $text = preg_replace( '![\x00-\x08\x0b\x0c\x0e-\x1f]!', ' ', $text );
 706                         $text = $wgDebugLogPrefix . $text;
 707                         wfErrorLog( $text, $wgDebugLogFile );
 708                 }
 709         }
 710 }
 711
 712 /**
 713  * Returns true if debug logging should be suppressed if $wgDebugRawPage = false
 714  */
 715 function wfIsDebugRawPage() {
 716         static $cache;
 717         if ( $cache !== null ) {
 718                 return $cache;
 719         }
 720         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
 721         if ( ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' )
 722                 || (
 723                         isset( $_SERVER['SCRIPT_NAME'] )
 724                         && substr( $_SERVER['SCRIPT_NAME'], -8 ) == 'load.php'
 725                 ) )
 726         {
 727                 $cache = true;
 728         } else {
 729                 $cache = false;
 730         }
 731         return $cache;
 732 }
 733
 734 /**
 735  * Get microsecond timestamps for debug logs
 736  *
 737  * @return string
 738  */
 739 function wfDebugTimer() {
 740         global $wgDebugTimestamps;
 741         if ( !$wgDebugTimestamps ) {
 742                 return '';
 743         }
 744         static $start = null;
 745
 746         if ( $start === null ) {
 747                 $start = microtime( true );
 748                 $prefix = "\n$start";
 749         } else {
 750                 $prefix = sprintf( "%6.4f", microtime( true ) - $start );
 751         }
 752
 753         return $prefix . '  ';
 754 }
 755
 756 /**
 757  * Send a line giving PHP memory usage.
 758  *
 759  * @param $exact Bool: print exact values instead of kilobytes (default: false)
 760  */
 761 function wfDebugMem( $exact = false ) {
 762         $mem = memory_get_usage();
 763         if( !$exact ) {
 764                 $mem = floor( $mem / 1024 ) . ' kilobytes';
 765         } else {
 766                 $mem .= ' bytes';
 767         }
 768         wfDebug( "Memory usage: $mem\n" );
 769 }
 770
 771 /**
 772  * Send a line to a supplementary debug log file, if configured, or main debug log if not.
 773  * $wgDebugLogGroups[$logGroup] should be set to a filename to send to a separate log.
 774  *
 775  * @param $logGroup String
 776  * @param $text String
 777  * @param $public Bool: whether to log the event in the public log if no private
 778  *                     log file is specified, (default true)
 779  */
 780 function wfDebugLog( $logGroup, $text, $public = true ) {
 781         global $wgDebugLogGroups, $wgShowHostnames;
 782         $text = trim( $text ) . "\n";
 783         if( isset( $wgDebugLogGroups[$logGroup] ) ) {
 784                 $time = wfTimestamp( TS_DB );
 785                 $wiki = wfWikiID();
 786                 if ( $wgShowHostnames ) {
 787                         $host = wfHostname();
 788                 } else {
 789                         $host = '';
 790                 }
 791                 if ( wfRunHooks( 'Debug', array( $text, $logGroup ) ) ) {
 792                         wfErrorLog( "$time $host $wiki: $text", $wgDebugLogGroups[$logGroup] );
 793                 }
 794         } elseif ( $public === true ) {
 795                 wfDebug( $text, true );
 796         }
 797 }
 798
 799 /**
 800  * Log for database errors
 801  *
 802  * @param $text String: database error message.
 803  */
 804 function wfLogDBError( $text ) {
 805         global $wgDBerrorLog, $wgDBname;
 806         if ( $wgDBerrorLog ) {
 807                 $host = trim(`hostname`);
 808                 $text = date( 'D M j G:i:s T Y' ) . "\t$host\t$wgDBname\t$text";
 809                 wfErrorLog( $text, $wgDBerrorLog );
 810         }
 811 }
 812
 813 /**
 814  * Log to a file without getting "file size exceeded" signals.
 815  *
 816  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
 817  * send lines to the specified port, prefixed by the specified prefix and a space.
 818  *
 819  * @param $text String
 820  * @param $file String filename
 821  */
 822 function wfErrorLog( $text, $file ) {
 823         if ( substr( $file, 0, 4 ) == 'udp:' ) {
 824                 # Needs the sockets extension
 825                 if ( preg_match( '!^(tcp|udp):(?://)?\[([0-9a-fA-F:]+)\]:(\d+)(?:/(.*))?$!', $file, $m ) ) {
 826                         // IPv6 bracketed host
 827                         $host = $m[2];
 828                         $port = intval( $m[3] );
 829                         $prefix = isset( $m[4] ) ? $m[4] : false;
 830                         $domain = AF_INET6;
 831                 } elseif ( preg_match( '!^(tcp|udp):(?://)?([a-zA-Z0-9.-]+):(\d+)(?:/(.*))?$!', $file, $m ) ) {
 832                         $host = $m[2];
 833                         if ( !IP::isIPv4( $host ) ) {
 834                                 $host = gethostbyname( $host );
 835                         }
 836                         $port = intval( $m[3] );
 837                         $prefix = isset( $m[4] ) ? $m[4] : false;
 838                         $domain = AF_INET;
 839                 } else {
 840                         throw new MWException( __METHOD__ . ': Invalid UDP specification' );
 841                 }
 842
 843                 // Clean it up for the multiplexer
 844                 if ( strval( $prefix ) !== '' ) {
 845                         $text = preg_replace( '/^/m', $prefix . ' ', $text );
 846
 847                         // Limit to 64KB
 848                         if ( strlen( $text ) > 65534 ) {
 849                                 $text = substr( $text, 0, 65534 );
 850                         }
 851
 852                         if ( substr( $text, -1 ) != "\n" ) {
 853                                 $text .= "\n";
 854                         }
 855                 } elseif ( strlen( $text ) > 65535 ) {
 856                         $text = substr( $text, 0, 65535 );
 857                 }
 858
 859                 $sock = socket_create( $domain, SOCK_DGRAM, SOL_UDP );
 860                 if ( !$sock ) {
 861                         return;
 862                 }
 863                 socket_sendto( $sock, $text, strlen( $text ), 0, $host, $port );
 864                 socket_close( $sock );
 865         } else {
 866                 wfSuppressWarnings();
 867                 $exists = file_exists( $file );
 868                 $size = $exists ? filesize( $file ) : false;
 869                 if ( !$exists || ( $size !== false && $size + strlen( $text ) < 0x7fffffff ) ) {
 870                         file_put_contents( $file, $text, FILE_APPEND );
 871                 }
 872                 wfRestoreWarnings();
 873         }
 874 }
 875
 876 /**
 877  * @todo document
 878  */
 879 function wfLogProfilingData() {
 880         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
 881         global $wgProfileLimit, $wgUser;
 882
 883         $profiler = Profiler::instance();
 884
 885         # Profiling must actually be enabled...
 886         if ( $profiler->isStub() ) {
 887                 return;
 888         }
 889
 890         // Get total page request time and only show pages that longer than
 891         // $wgProfileLimit time (default is 0)
 892         $now = wfTime();
 893         $elapsed = $now - $wgRequestTime;
 894         if ( $elapsed <= $wgProfileLimit ) {
 895                 return;
 896         }
 897
 898         $profiler->logData();
 899
 900         // Check whether this should be logged in the debug file.
 901         if ( $wgDebugLogFile == '' || ( !$wgDebugRawPage && wfIsDebugRawPage() ) ) {
 902                 return;
 903         }
 904
 905         $forward = '';
 906         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
 907                 $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
 908         }
 909         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
 910                 $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
 911         }
 912         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
 913                 $forward .= ' from ' . $_SERVER['HTTP_FROM'];
 914         }
 915         if ( $forward ) {
 916                 $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
 917         }
 918         // Don't load $wgUser at this late stage just for statistics purposes
 919         // @todo FIXME: We can detect some anons even if it is not loaded. See User::getId()
 920         if ( $wgUser->isItemLoaded( 'id' ) && $wgUser->isAnon() ) {
 921                 $forward .= ' anon';
 922         }
 923         $log = sprintf( "%s\t%04.3f\t%s\n",
 924                 gmdate( 'YmdHis' ), $elapsed,
 925                 urldecode( $wgRequest->getRequestURL() . $forward ) );
 926
 927         wfErrorLog( $log . $profiler->getOutput(), $wgDebugLogFile );
 928 }
 929
 930 /**
 931  * Check if the wiki read-only lock file is present. This can be used to lock
 932  * off editing functions, but doesn't guarantee that the database will not be
 933  * modified.
 934  *
 935  * @return bool
 936  */
 937 function wfReadOnly() {
 938         global $wgReadOnlyFile, $wgReadOnly;
 939
 940         if ( !is_null( $wgReadOnly ) ) {
 941                 return (bool)$wgReadOnly;
 942         }
 943         if ( $wgReadOnlyFile == '' ) {
 944                 return false;
 945         }
 946         // Set $wgReadOnly for faster access next time
 947         if ( is_file( $wgReadOnlyFile ) ) {
 948                 $wgReadOnly = file_get_contents( $wgReadOnlyFile );
 949         } else {
 950                 $wgReadOnly = false;
 951         }
 952         return (bool)$wgReadOnly;
 953 }
 954
 955 function wfReadOnlyReason() {
 956         global $wgReadOnly;
 957         wfReadOnly();
 958         return $wgReadOnly;
 959 }
 960
 961 /**
 962  * Return a Language object from $langcode
 963  *
 964  * @param $langcode Mixed: either:
 965  *                  - a Language object
 966  *                  - code of the language to get the message for, if it is
 967  *                    a valid code create a language for that language, if
 968  *                    it is a string but not a valid code then make a basic
 969  *                    language object
 970  *                  - a boolean: if it's false then use the current users
 971  *                    language (as a fallback for the old parameter
 972  *                    functionality), or if it is true then use the wikis
 973  * @return Language object
 974  */
 975 function wfGetLangObj( $langcode = false ) {
 976         # Identify which language to get or create a language object for.
 977         # Using is_object here due to Stub objects.
 978         if( is_object( $langcode ) ) {
 979                 # Great, we already have the object (hopefully)!
 980                 return $langcode;
 981         }
 982
 983         global $wgContLang, $wgLanguageCode;
 984         if( $langcode === true || $langcode === $wgLanguageCode ) {
 985                 # $langcode is the language code of the wikis content language object.
 986                 # or it is a boolean and value is true
 987                 return $wgContLang;
 988         }
 989
 990         global $wgLang;
 991         if( $langcode === false || $langcode === $wgLang->getCode() ) {
 992                 # $langcode is the language code of user language object.
 993                 # or it was a boolean and value is false
 994                 return $wgLang;
 995         }
 996
 997         $validCodes = array_keys( Language::getLanguageNames() );
 998         if( in_array( $langcode, $validCodes ) ) {
 999                 # $langcode corresponds to a valid language.
1000                 return Language::factory( $langcode );
1001         }
1002
1003         # $langcode is a string, but not a valid language code; use content language.
1004         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
1005         return $wgContLang;
1006 }
1007
1008 /**
1009  * Old function when $wgBetterDirectionality existed
1010  * Removed in core, kept in extensions for backwards compat.
1011  *
1012  * @deprecated since 1.18
1013  * @return Language
1014  */
1015 function wfUILang() {
1016         global $wgLang;
1017         return $wgLang;
1018 }
1019
1020 /**
1021  * This is the new function for getting translated interface messages.
1022  * See the Message class for documentation how to use them.
1023  * The intention is that this function replaces all old wfMsg* functions.
1024  * @param $key \string Message key.
1025  * Varargs: normal message parameters.
1026  * @return Message
1027  * @since 1.17
1028  */
1029 function wfMessage( $key /*...*/) {
1030         $params = func_get_args();
1031         array_shift( $params );
1032         if ( isset( $params[0] ) && is_array( $params[0] ) ) {
1033                 $params = $params[0];
1034         }
1035         return new Message( $key, $params );
1036 }
1037
1038 /**
1039  * This function accepts multiple message keys and returns a message instance
1040  * for the first message which is non-empty. If all messages are empty then an
1041  * instance of the first message key is returned.
1042  * @param varargs: message keys
1043  * @return Message
1044  * @since 1.18
1045  */
1046 function wfMessageFallback( /*...*/ ) {
1047         $args = func_get_args();
1048         return MWFunction::callArray( 'Message::newFallbackSequence', $args );
1049 }
1050
1051 /**
1052  * Get a message from anywhere, for the current user language.
1053  *
1054  * Use wfMsgForContent() instead if the message should NOT
1055  * change depending on the user preferences.
1056  *
1057  * @param $key String: lookup key for the message, usually
1058  *    defined in languages/Language.php
1059  *
1060  * Parameters to the message, which can be used to insert variable text into
1061  * it, can be passed to this function in the following formats:
1062  * - One per argument, starting at the second parameter
1063  * - As an array in the second parameter
1064  * These are not shown in the function definition.
1065  *
1066  * @return String
1067  */
1068 function wfMsg( $key ) {
1069         $args = func_get_args();
1070         array_shift( $args );
1071         return wfMsgReal( $key, $args );
1072 }
1073
1074 /**
1075  * Same as above except doesn't transform the message
1076  *
1077  * @param $key String
1078  * @return String
1079  */
1080 function wfMsgNoTrans( $key ) {
1081         $args = func_get_args();
1082         array_shift( $args );
1083         return wfMsgReal( $key, $args, true, false, false );
1084 }
1085
1086 /**
1087  * Get a message from anywhere, for the current global language
1088  * set with $wgLanguageCode.
1089  *
1090  * Use this if the message should NOT change dependent on the
1091  * language set in the user's preferences. This is the case for
1092  * most text written into logs, as well as link targets (such as
1093  * the name of the copyright policy page). Link titles, on the
1094  * other hand, should be shown in the UI language.
1095  *
1096  * Note that MediaWiki allows users to change the user interface
1097  * language in their preferences, but a single installation
1098  * typically only contains content in one language.
1099  *
1100  * Be wary of this distinction: If you use wfMsg() where you should
1101  * use wfMsgForContent(), a user of the software may have to
1102  * customize potentially hundreds of messages in
1103  * order to, e.g., fix a link in every possible language.
1104  *
1105  * @param $key String: lookup key for the message, usually
1106  *     defined in languages/Language.php
1107  * @return String
1108  */
1109 function wfMsgForContent( $key ) {
1110         global $wgForceUIMsgAsContentMsg;
1111         $args = func_get_args();
1112         array_shift( $args );
1113         $forcontent = true;
1114         if( is_array( $wgForceUIMsgAsContentMsg ) &&
1115                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
1116         {
1117                 $forcontent = false;
1118         }
1119         return wfMsgReal( $key, $args, true, $forcontent );
1120 }
1121
1122 /**
1123  * Same as above except doesn't transform the message
1124  *
1125  * @param $key String
1126  * @return String
1127  */
1128 function wfMsgForContentNoTrans( $key ) {
1129         global $wgForceUIMsgAsContentMsg;
1130         $args = func_get_args();
1131         array_shift( $args );
1132         $forcontent = true;
1133         if( is_array( $wgForceUIMsgAsContentMsg ) &&
1134                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
1135         {
1136                 $forcontent = false;
1137         }
1138         return wfMsgReal( $key, $args, true, $forcontent, false );
1139 }
1140
1141 /**
1142  * Really get a message
1143  *
1144  * @param $key String: key to get.
1145  * @param $args
1146  * @param $useDB Boolean
1147  * @param $forContent Mixed: Language code, or false for user lang, true for content lang.
1148  * @param $transform Boolean: Whether or not to transform the message.
1149  * @return String: the requested message.
1150  */
1151 function wfMsgReal( $key, $args, $useDB = true, $forContent = false, $transform = true ) {
1152         wfProfileIn( __METHOD__ );
1153         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
1154         $message = wfMsgReplaceArgs( $message, $args );
1155         wfProfileOut( __METHOD__ );
1156         return $message;
1157 }
1158
1159 /**
1160  * Fetch a message string value, but don't replace any keys yet.
1161  *
1162  * @param $key String
1163  * @param $useDB Bool
1164  * @param $langCode String: Code of the language to get the message for, or
1165  *                  behaves as a content language switch if it is a boolean.
1166  * @param $transform Boolean: whether to parse magic words, etc.
1167  * @return string
1168  */
1169 function wfMsgGetKey( $key, $useDB = true, $langCode = false, $transform = true ) {
1170         wfRunHooks( 'NormalizeMessageKey', array( &$key, &$useDB, &$langCode, &$transform ) );
1171
1172         $cache = MessageCache::singleton();
1173         $message = $cache->get( $key, $useDB, $langCode );
1174         if( $message === false ) {
1175                 $message = '&lt;' . htmlspecialchars( $key ) . '&gt;';
1176         } elseif ( $transform ) {
1177                 $message = $cache->transform( $message );
1178         }
1179         return $message;
1180 }
1181
1182 /**
1183  * Replace message parameter keys on the given formatted output.
1184  *
1185  * @param $message String
1186  * @param $args Array
1187  * @return string
1188  * @private
1189  */
1190 function wfMsgReplaceArgs( $message, $args ) {
1191         # Fix windows line-endings
1192         # Some messages are split with explode("\n", $msg)
1193         $message = str_replace( "\r", '', $message );
1194
1195         // Replace arguments
1196         if ( count( $args ) ) {
1197                 if ( is_array( $args[0] ) ) {
1198                         $args = array_values( $args[0] );
1199                 }
1200                 $replacementKeys = array();
1201                 foreach( $args as $n => $param ) {
1202                         $replacementKeys['$' . ( $n + 1 )] = $param;
1203                 }
1204                 $message = strtr( $message, $replacementKeys );
1205         }
1206
1207         return $message;
1208 }
1209
1210 /**
1211  * Return an HTML-escaped version of a message.
1212  * Parameter replacements, if any, are done *after* the HTML-escaping,
1213  * so parameters may contain HTML (eg links or form controls). Be sure
1214  * to pre-escape them if you really do want plaintext, or just wrap
1215  * the whole thing in htmlspecialchars().
1216  *
1217  * @param $key String
1218  * @param string ... parameters
1219  * @return string
1220  */
1221 function wfMsgHtml( $key ) {
1222         $args = func_get_args();
1223         array_shift( $args );
1224         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key ) ), $args );
1225 }
1226
1227 /**
1228  * Return an HTML version of message
1229  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
1230  * so parameters may contain HTML (eg links or form controls). Be sure
1231  * to pre-escape them if you really do want plaintext, or just wrap
1232  * the whole thing in htmlspecialchars().
1233  *
1234  * @param $key String
1235  * @param string ... parameters
1236  * @return string
1237  */
1238 function wfMsgWikiHtml( $key ) {
1239         $args = func_get_args();
1240         array_shift( $args );
1241         return wfMsgReplaceArgs(
1242                 MessageCache::singleton()->parse( wfMsgGetKey( $key ), null,
1243                 /* can't be set to false */ true, /* interface */ true )->getText(),
1244                 $args );
1245 }
1246
1247 /**
1248  * Returns message in the requested format
1249  * @param $key String: key of the message
1250  * @param $options Array: processing rules. Can take the following options:
1251  *   <i>parse</i>: parses wikitext to HTML
1252  *   <i>parseinline</i>: parses wikitext to HTML and removes the surrounding
1253  *       p's added by parser or tidy
1254  *   <i>escape</i>: filters message through htmlspecialchars
1255  *   <i>escapenoentities</i>: same, but allows entity references like &#160; through
1256  *   <i>replaceafter</i>: parameters are substituted after parsing or escaping
1257  *   <i>parsemag</i>: transform the message using magic phrases
1258  *   <i>content</i>: fetch message for content language instead of interface
1259  * Also can accept a single associative argument, of the form 'language' => 'xx':
1260  *   <i>language</i>: Language object or language code to fetch message for
1261  *       (overriden by <i>content</i>).
1262  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
1263  *
1264  * @return String
1265  */
1266 function wfMsgExt( $key, $options ) {
1267         $args = func_get_args();
1268         array_shift( $args );
1269         array_shift( $args );
1270         $options = (array)$options;
1271
1272         foreach( $options as $arrayKey => $option ) {
1273                 if( !preg_match( '/^[0-9]+|language$/', $arrayKey ) ) {
1274                         # An unknown index, neither numeric nor "language"
1275                         wfWarn( "wfMsgExt called with incorrect parameter key $arrayKey", 1, E_USER_WARNING );
1276                 } elseif( preg_match( '/^[0-9]+$/', $arrayKey ) && !in_array( $option,
1277                 array( 'parse', 'parseinline', 'escape', 'escapenoentities',
1278                 'replaceafter', 'parsemag', 'content' ) ) ) {
1279                         # A numeric index with unknown value
1280                         wfWarn( "wfMsgExt called with incorrect parameter $option", 1, E_USER_WARNING );
1281                 }
1282         }
1283
1284         if( in_array( 'content', $options, true ) ) {
1285                 $forContent = true;
1286                 $langCode = true;
1287                 $langCodeObj = null;
1288         } elseif( array_key_exists( 'language', $options ) ) {
1289                 $forContent = false;
1290                 $langCode = wfGetLangObj( $options['language'] );
1291                 $langCodeObj = $langCode;
1292         } else {
1293                 $forContent = false;
1294                 $langCode = false;
1295                 $langCodeObj = null;
1296         }
1297
1298         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
1299
1300         if( !in_array( 'replaceafter', $options, true ) ) {
1301                 $string = wfMsgReplaceArgs( $string, $args );
1302         }
1303
1304         $messageCache = MessageCache::singleton();
1305         if( in_array( 'parse', $options, true ) ) {
1306                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj )->getText();
1307         } elseif ( in_array( 'parseinline', $options, true ) ) {
1308                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj )->getText();
1309                 $m = array();
1310                 if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
1311                         $string = $m[1];
1312                 }
1313         } elseif ( in_array( 'parsemag', $options, true ) ) {
1314                 $string = $messageCache->transform( $string,
1315                                 !$forContent, $langCodeObj );
1316         }
1317
1318         if ( in_array( 'escape', $options, true ) ) {
1319                 $string = htmlspecialchars ( $string );
1320         } elseif ( in_array( 'escapenoentities', $options, true ) ) {
1321                 $string = Sanitizer::escapeHtmlAllowEntities( $string );
1322         }
1323
1324         if( in_array( 'replaceafter', $options, true ) ) {
1325                 $string = wfMsgReplaceArgs( $string, $args );
1326         }
1327
1328         return $string;
1329 }
1330
1331 /**
1332  * Since wfMsg() and co suck, they don't return false if the message key they
1333  * looked up didn't exist but a XHTML string, this function checks for the
1334  * nonexistance of messages by checking the MessageCache::get() result directly.
1335  *
1336  * @param $key      String: the message key looked up
1337  * @return Boolean True if the message *doesn't* exist.
1338  */
1339 function wfEmptyMsg( $key ) {
1340         return MessageCache::singleton()->get( $key, /*useDB*/true, /*content*/false ) === false;
1341 }
1342
1343 /**
1344  * Throw a debugging exception. This function previously once exited the process,
1345  * but now throws an exception instead, with similar results.
1346  *
1347  * @param $msg String: message shown when dieing.
1348  */
1349 function wfDebugDieBacktrace( $msg = '' ) {
1350         throw new MWException( $msg );
1351 }
1352
1353 /**
1354  * Fetch server name for use in error reporting etc.
1355  * Use real server name if available, so we know which machine
1356  * in a server farm generated the current page.
1357  *
1358  * @return string
1359  */
1360 function wfHostname() {
1361         static $host;
1362         if ( is_null( $host ) ) {
1363                 if ( function_exists( 'posix_uname' ) ) {
1364                         // This function not present on Windows
1365                         $uname = posix_uname();
1366                 } else {
1367                         $uname = false;
1368                 }
1369                 if( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1370                         $host = $uname['nodename'];
1371                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1372                         # Windows computer name
1373                         $host = getenv( 'COMPUTERNAME' );
1374                 } else {
1375                         # This may be a virtual server.
1376                         $host = $_SERVER['SERVER_NAME'];
1377                 }
1378         }
1379         return $host;
1380 }
1381
1382 /**
1383  * Returns a HTML comment with the elapsed time since request.
1384  * This method has no side effects.
1385  *
1386  * @return string
1387  */
1388 function wfReportTime() {
1389         global $wgRequestTime, $wgShowHostnames;
1390
1391         $now = wfTime();
1392         $elapsed = $now - $wgRequestTime;
1393
1394         return $wgShowHostnames
1395                 ? sprintf( '<!-- Served by %s in %01.3f secs. -->', wfHostname(), $elapsed )
1396                 : sprintf( '<!-- Served in %01.3f secs. -->', $elapsed );
1397 }
1398
1399 /**
1400  * Safety wrapper for debug_backtrace().
1401  *
1402  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
1403  * murky circumstances, which may be triggered in part by stub objects
1404  * or other fancy talkin'.
1405  *
1406  * Will return an empty array if Zend Optimizer is detected or if
1407  * debug_backtrace is disabled, otherwise the output from
1408  * debug_backtrace() (trimmed).
1409  *
1410  * @param $limit int This parameter can be used to limit the number of stack frames returned
1411  *
1412  * @return array of backtrace information
1413  */
1414 function wfDebugBacktrace( $limit = 0 ) {
1415         static $disabled = null;
1416
1417         if( extension_loaded( 'Zend Optimizer' ) ) {
1418                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
1419                 return array();
1420         }
1421
1422         if ( is_null( $disabled ) ) {
1423                 $disabled = false;
1424                 $functions = explode( ',', ini_get( 'disable_functions' ) );
1425                 $functions = array_map( 'trim', $functions );
1426                 $functions = array_map( 'strtolower', $functions );
1427                 if ( in_array( 'debug_backtrace', $functions ) ) {
1428                         wfDebug( "debug_backtrace is in disabled_functions\n" );
1429                         $disabled = true;
1430                 }
1431         }
1432         if ( $disabled ) {
1433                 return array();
1434         }
1435
1436         if ( $limit && version_compare( PHP_VERSION, '5.4.0', '>=' ) ) {
1437                 return array_slice( debug_backtrace( DEBUG_BACKTRACE_PROVIDE_OBJECT, $limit ), 1 );
1438         } else {
1439                 return array_slice( debug_backtrace(), 1 );
1440         }
1441 }
1442
1443 /**
1444  * Get a debug backtrace as a string
1445  *
1446  * @return string
1447  */
1448 function wfBacktrace() {
1449         global $wgCommandLineMode;
1450
1451         if ( $wgCommandLineMode ) {
1452                 $msg = '';
1453         } else {
1454                 $msg = "<ul>\n";
1455         }
1456         $backtrace = wfDebugBacktrace();
1457         foreach( $backtrace as $call ) {
1458                 if( isset( $call['file'] ) ) {
1459                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
1460                         $file = $f[count( $f ) - 1];
1461                 } else {
1462                         $file = '-';
1463                 }
1464                 if( isset( $call['line'] ) ) {
1465                         $line = $call['line'];
1466                 } else {
1467                         $line = '-';
1468                 }
1469                 if ( $wgCommandLineMode ) {
1470                         $msg .= "$file line $line calls ";
1471                 } else {
1472                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
1473                 }
1474                 if( !empty( $call['class'] ) ) {
1475                         $msg .= $call['class'] . $call['type'];
1476                 }
1477                 $msg .= $call['function'] . '()';
1478
1479                 if ( $wgCommandLineMode ) {
1480                         $msg .= "\n";
1481                 } else {
1482                         $msg .= "</li>\n";
1483                 }
1484         }
1485         if ( $wgCommandLineMode ) {
1486                 $msg .= "\n";
1487         } else {
1488                 $msg .= "</ul>\n";
1489         }
1490
1491         return $msg;
1492 }
1493
1494 /**
1495  * Get the name of the function which called this function
1496  *
1497  * @param $level Int
1498  * @return Bool|string
1499  */
1500 function wfGetCaller( $level = 2 ) {
1501         $backtrace = wfDebugBacktrace( $level );
1502         if ( isset( $backtrace[$level] ) ) {
1503                 return wfFormatStackFrame( $backtrace[$level] );
1504         } else {
1505                 $caller = 'unknown';
1506         }
1507         return $caller;
1508 }
1509
1510 /**
1511  * Return a string consisting of callers in the stack. Useful sometimes
1512  * for profiling specific points.
1513  *
1514  * @param $limit The maximum depth of the stack frame to return, or false for
1515  *               the entire stack.
1516  * @return String
1517  */
1518 function wfGetAllCallers( $limit = 3 ) {
1519         $trace = array_reverse( wfDebugBacktrace() );
1520         if ( !$limit || $limit > count( $trace ) - 1 ) {
1521                 $limit = count( $trace ) - 1;
1522         }
1523         $trace = array_slice( $trace, -$limit - 1, $limit );
1524         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1525 }
1526
1527 /**
1528  * Return a string representation of frame
1529  *
1530  * @param $frame Array
1531  * @return Bool
1532  */
1533 function wfFormatStackFrame( $frame ) {
1534         return isset( $frame['class'] ) ?
1535                 $frame['class'] . '::' . $frame['function'] :
1536                 $frame['function'];
1537 }
1538
1539
1540 /* Some generic result counters, pulled out of SearchEngine */
1541
1542
1543 /**
1544  * @todo document
1545  *
1546  * @param $offset Int
1547  * @param $limit Int
1548  * @return String
1549  */
1550 function wfShowingResults( $offset, $limit ) {
1551         global $wgLang;
1552         return wfMsgExt(
1553                 'showingresults',
1554                 array( 'parseinline' ),
1555                 $wgLang->formatNum( $limit ),
1556                 $wgLang->formatNum( $offset + 1 )
1557         );
1558 }
1559
1560 /**
1561  * Generate (prev x| next x) (20|50|100...) type links for paging
1562  *
1563  * @param $offset String
1564  * @param $limit Integer
1565  * @param $link String
1566  * @param $query String: optional URL query parameter string
1567  * @param $atend Bool: optional param for specified if this is the last page
1568  * @return String
1569  */
1570 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
1571         global $wgLang;
1572         $fmtLimit = $wgLang->formatNum( $limit );
1573         // @todo FIXME: Why on earth this needs one message for the text and another one for tooltip?
1574         # Get prev/next link display text
1575         $prev = wfMsgExt( 'prevn', array( 'parsemag', 'escape' ), $fmtLimit );
1576         $next = wfMsgExt( 'nextn', array( 'parsemag', 'escape' ), $fmtLimit );
1577         # Get prev/next link title text
1578         $pTitle = wfMsgExt( 'prevn-title', array( 'parsemag', 'escape' ), $fmtLimit );
1579         $nTitle = wfMsgExt( 'nextn-title', array( 'parsemag', 'escape' ), $fmtLimit );
1580         # Fetch the title object
1581         if( is_object( $link ) ) {
1582                 $title =& $link;
1583         } else {
1584                 $title = Title::newFromText( $link );
1585                 if( is_null( $title ) ) {
1586                         return false;
1587                 }
1588         }
1589         # Make 'previous' link
1590         if( 0 != $offset ) {
1591                 $po = $offset - $limit;
1592                 $po = max( $po, 0 );
1593                 $q = "limit={$limit}&offset={$po}";
1594                 if( $query != '' ) {
1595                         $q .= '&' . $query;
1596                 }
1597                 $plink = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$pTitle}\" class=\"mw-prevlink\">{$prev}</a>";
1598         } else {
1599                 $plink = $prev;
1600         }
1601         # Make 'next' link
1602         $no = $offset + $limit;
1603         $q = "limit={$limit}&offset={$no}";
1604         if( $query != '' ) {
1605                 $q .= '&' . $query;
1606         }
1607         if( $atend ) {
1608                 $nlink = $next;
1609         } else {
1610                 $nlink = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$nTitle}\" class=\"mw-nextlink\">{$next}</a>";
1611         }
1612         # Make links to set number of items per page
1613         $nums = $wgLang->pipeList( array(
1614                 wfNumLink( $offset, 20, $title, $query ),
1615                 wfNumLink( $offset, 50, $title, $query ),
1616                 wfNumLink( $offset, 100, $title, $query ),
1617                 wfNumLink( $offset, 250, $title, $query ),
1618                 wfNumLink( $offset, 500, $title, $query )
1619         ) );
1620         return wfMsgHtml( 'viewprevnext', $plink, $nlink, $nums );
1621 }
1622
1623 /**
1624  * Generate links for (20|50|100...) items-per-page links
1625  *
1626  * @param $offset String
1627  * @param $limit Integer
1628  * @param $title Title
1629  * @param $query String: optional URL query parameter string
1630  */
1631 function wfNumLink( $offset, $limit, $title, $query = '' ) {
1632         global $wgLang;
1633         if( $query == '' ) {
1634                 $q = '';
1635         } else {
1636                 $q = $query.'&';
1637         }
1638         $q .= "limit={$limit}&offset={$offset}";
1639         $fmtLimit = $wgLang->formatNum( $limit );
1640         $lTitle = wfMsgExt( 'shown-title', array( 'parsemag', 'escape' ), $limit );
1641         $s = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$lTitle}\" class=\"mw-numlink\">{$fmtLimit}</a>";
1642         return $s;
1643 }
1644
1645 /**
1646  * @todo document
1647  * @todo FIXME: We may want to blacklist some broken browsers
1648  *
1649  * @param $force Bool
1650  * @return bool Whereas client accept gzip compression
1651  */
1652 function wfClientAcceptsGzip( $force = false ) {
1653         static $result = null;
1654         if ( $result === null || $force ) {
1655                 $result = false;
1656                 if( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1657                         # @todo FIXME: We may want to blacklist some broken browsers
1658                         $m = array();
1659                         if( preg_match(
1660                                 '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1661                                 $_SERVER['HTTP_ACCEPT_ENCODING'],
1662                                 $m )
1663                         )
1664                         {
1665                                 if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1666                                         $result = false;
1667                                         return $result;
1668                                 }
1669                                 wfDebug( " accepts gzip\n" );
1670                                 $result = true;
1671                         }
1672                 }
1673         }
1674         return $result;
1675 }
1676
1677 /**
1678  * Obtain the offset and limit values from the request string;
1679  * used in special pages
1680  *
1681  * @param $deflimit Int default limit if none supplied
1682  * @param $optionname String Name of a user preference to check against
1683  * @return array
1684  *
1685  */
1686 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
1687         global $wgRequest;
1688         return $wgRequest->getLimitOffset( $deflimit, $optionname );
1689 }
1690
1691 /**
1692  * Escapes the given text so that it may be output using addWikiText()
1693  * without any linking, formatting, etc. making its way through. This
1694  * is achieved by substituting certain characters with HTML entities.
1695  * As required by the callers, <nowiki> is not used.
1696  *
1697  * @param $text String: text to be escaped
1698  * @return String
1699  */
1700 function wfEscapeWikiText( $text ) {
1701         $text = strtr( "\n$text", array(
1702                 '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
1703                 '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
1704                 '{' => '&#123;', '|' => '&#124;', '}' => '&#125;',
1705                 "\n#" => "\n&#35;", "\n*" => "\n&#42;",
1706                 "\n:" => "\n&#58;", "\n;" => "\n&#59;",
1707                 '://' => '&#58;//', 'ISBN ' => 'ISBN&#32;', 'RFC ' => 'RFC&#32;',
1708         ) );
1709         return substr( $text, 1 );
1710 }
1711
1712 /**
1713  * Get the current unix timetstamp with microseconds.  Useful for profiling
1714  * @return Float
1715  */
1716 function wfTime() {
1717         return microtime( true );
1718 }
1719
1720 /**
1721  * Sets dest to source and returns the original value of dest
1722  * If source is NULL, it just returns the value, it doesn't set the variable
1723  * If force is true, it will set the value even if source is NULL
1724  *
1725  * @param $dest Mixed
1726  * @param $source Mixed
1727  * @param $force Bool
1728  * @return Mixed
1729  */
1730 function wfSetVar( &$dest, $source, $force = false ) {
1731         $temp = $dest;
1732         if ( !is_null( $source ) || $force ) {
1733                 $dest = $source;
1734         }
1735         return $temp;
1736 }
1737
1738 /**
1739  * As for wfSetVar except setting a bit
1740  *
1741  * @param $dest Int
1742  * @param $bit Int
1743  * @param $state Bool
1744  */
1745 function wfSetBit( &$dest, $bit, $state = true ) {
1746         $temp = (bool)( $dest & $bit );
1747         if ( !is_null( $state ) ) {
1748                 if ( $state ) {
1749                         $dest |= $bit;
1750                 } else {
1751                         $dest &= ~$bit;
1752                 }
1753         }
1754         return $temp;
1755 }
1756
1757 /**
1758  * Windows-compatible version of escapeshellarg()
1759  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
1760  * function puts single quotes in regardless of OS.
1761  *
1762  * Also fixes the locale problems on Linux in PHP 5.2.6+ (bug backported to
1763  * earlier distro releases of PHP)
1764  *
1765  * @param varargs
1766  * @return String
1767  */
1768 function wfEscapeShellArg( ) {
1769         wfInitShellLocale();
1770
1771         $args = func_get_args();
1772         $first = true;
1773         $retVal = '';
1774         foreach ( $args as $arg ) {
1775                 if ( !$first ) {
1776                         $retVal .= ' ';
1777                 } else {
1778                         $first = false;
1779                 }
1780
1781                 if ( wfIsWindows() ) {
1782                         // Escaping for an MSVC-style command line parser and CMD.EXE
1783                         // Refs:
1784                         //  * http://web.archive.org/web/20020708081031/http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
1785                         //  * http://technet.microsoft.com/en-us/library/cc723564.aspx
1786                         //  * Bug #13518
1787                         //  * CR r63214
1788                         // Double the backslashes before any double quotes. Escape the double quotes.
1789                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
1790                         $arg = '';
1791                         $iteration = 0;
1792                         foreach ( $tokens as $token ) {
1793                                 if ( $iteration % 2 == 1 ) {
1794                                         // Delimiter, a double quote preceded by zero or more slashes
1795                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
1796                                 } elseif ( $iteration % 4 == 2 ) {
1797                                         // ^ in $token will be outside quotes, need to be escaped
1798                                         $arg .= str_replace( '^', '^^', $token );
1799                                 } else { // $iteration % 4 == 0
1800                                         // ^ in $token will appear inside double quotes, so leave as is
1801                                         $arg .= $token;
1802                                 }
1803                                 $iteration++;
1804                         }
1805                         // Double the backslashes before the end of the string, because
1806                         // we will soon add a quote
1807                         $m = array();
1808                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
1809                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
1810                         }
1811
1812                         // Add surrounding quotes
1813                         $retVal .= '"' . $arg . '"';
1814                 } else {
1815                         $retVal .= escapeshellarg( $arg );
1816                 }
1817         }
1818         return $retVal;
1819 }
1820
1821 /**
1822  * wfMerge attempts to merge differences between three texts.
1823  * Returns true for a clean merge and false for failure or a conflict.
1824  *
1825  * @param $old String
1826  * @param $mine String
1827  * @param $yours String
1828  * @param $result String
1829  * @return Bool
1830  */
1831 function wfMerge( $old, $mine, $yours, &$result ) {
1832         global $wgDiff3;
1833
1834         # This check may also protect against code injection in
1835         # case of broken installations.
1836         wfSuppressWarnings();
1837         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
1838         wfRestoreWarnings();
1839
1840         if( !$haveDiff3 ) {
1841                 wfDebug( "diff3 not found\n" );
1842                 return false;
1843         }
1844
1845         # Make temporary files
1846         $td = wfTempDir();
1847         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1848         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
1849         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
1850
1851         fwrite( $oldtextFile, $old );
1852         fclose( $oldtextFile );
1853         fwrite( $mytextFile, $mine );
1854         fclose( $mytextFile );
1855         fwrite( $yourtextFile, $yours );
1856         fclose( $yourtextFile );
1857
1858         # Check for a conflict
1859         $cmd = $wgDiff3 . ' -a --overlap-only ' .
1860                 wfEscapeShellArg( $mytextName ) . ' ' .
1861                 wfEscapeShellArg( $oldtextName ) . ' ' .
1862                 wfEscapeShellArg( $yourtextName );
1863         $handle = popen( $cmd, 'r' );
1864
1865         if( fgets( $handle, 1024 ) ) {
1866                 $conflict = true;
1867         } else {
1868                 $conflict = false;
1869         }
1870         pclose( $handle );
1871
1872         # Merge differences
1873         $cmd = $wgDiff3 . ' -a -e --merge ' .
1874                 wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
1875         $handle = popen( $cmd, 'r' );
1876         $result = '';
1877         do {
1878                 $data = fread( $handle, 8192 );
1879                 if ( strlen( $data ) == 0 ) {
1880                         break;
1881                 }
1882                 $result .= $data;
1883         } while ( true );
1884         pclose( $handle );
1885         unlink( $mytextName );
1886         unlink( $oldtextName );
1887         unlink( $yourtextName );
1888
1889         if ( $result === '' && $old !== '' && !$conflict ) {
1890                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
1891                 $conflict = true;
1892         }
1893         return !$conflict;
1894 }
1895
1896 /**
1897  * Returns unified plain-text diff of two texts.
1898  * Useful for machine processing of diffs.
1899  *
1900  * @param $before String: the text before the changes.
1901  * @param $after String: the text after the changes.
1902  * @param $params String: command-line options for the diff command.
1903  * @return String: unified diff of $before and $after
1904  */
1905 function wfDiff( $before, $after, $params = '-u' ) {
1906         if ( $before == $after ) {
1907                 return '';
1908         }
1909
1910         global $wgDiff;
1911         wfSuppressWarnings();
1912         $haveDiff = $wgDiff && file_exists( $wgDiff );
1913         wfRestoreWarnings();
1914
1915         # This check may also protect against code injection in
1916         # case of broken installations.
1917         if( !$haveDiff ) {
1918                 wfDebug( "diff executable not found\n" );
1919                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
1920                 $format = new UnifiedDiffFormatter();
1921                 return $format->format( $diffs );
1922         }
1923
1924         # Make temporary files
1925         $td = wfTempDir();
1926         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1927         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
1928
1929         fwrite( $oldtextFile, $before );
1930         fclose( $oldtextFile );
1931         fwrite( $newtextFile, $after );
1932         fclose( $newtextFile );
1933
1934         // Get the diff of the two files
1935         $cmd = "$wgDiff " . $params . ' ' . wfEscapeShellArg( $oldtextName, $newtextName );
1936
1937         $h = popen( $cmd, 'r' );
1938
1939         $diff = '';
1940
1941         do {
1942                 $data = fread( $h, 8192 );
1943                 if ( strlen( $data ) == 0 ) {
1944                         break;
1945                 }
1946                 $diff .= $data;
1947         } while ( true );
1948
1949         // Clean up
1950         pclose( $h );
1951         unlink( $oldtextName );
1952         unlink( $newtextName );
1953
1954         // Kill the --- and +++ lines. They're not useful.
1955         $diff_lines = explode( "\n", $diff );
1956         if ( strpos( $diff_lines[0], '---' ) === 0 ) {
1957                 unset( $diff_lines[0] );
1958         }
1959         if ( strpos( $diff_lines[1], '+++' ) === 0 ) {
1960                 unset( $diff_lines[1] );
1961         }
1962
1963         $diff = implode( "\n", $diff_lines );
1964
1965         return $diff;
1966 }
1967
1968 /**
1969  * A wrapper around the PHP function var_export().
1970  * Either print it or add it to the regular output ($wgOut).
1971  *
1972  * @param $var A PHP variable to dump.
1973  */
1974 function wfVarDump( $var ) {
1975         global $wgOut;
1976         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
1977         if ( headers_sent() || !isset( $wgOut ) || !is_object( $wgOut ) ) {
1978                 print $s;
1979         } else {
1980                 $wgOut->addHTML( $s );
1981         }
1982 }
1983
1984 /**
1985  * Provide a simple HTTP error.
1986  *
1987  * @param $code Int|String
1988  * @param $label String
1989  * @param $desc String
1990  */
1991 function wfHttpError( $code, $label, $desc ) {
1992         global $wgOut;
1993         $wgOut->disable();
1994         header( "HTTP/1.0 $code $label" );
1995         header( "Status: $code $label" );
1996         $wgOut->sendCacheControl();
1997
1998         header( 'Content-type: text/html; charset=utf-8' );
1999         print "<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">".
2000                 '<html><head><title>' .
2001                 htmlspecialchars( $label ) .
2002                 '</title></head><body><h1>' .
2003                 htmlspecialchars( $label ) .
2004                 '</h1><p>' .
2005                 nl2br( htmlspecialchars( $desc ) ) .
2006                 "</p></body></html>\n";
2007 }
2008
2009 /**
2010  * Clear away any user-level output buffers, discarding contents.
2011  *
2012  * Suitable for 'starting afresh', for instance when streaming
2013  * relatively large amounts of data without buffering, or wanting to
2014  * output image files without ob_gzhandler's compression.
2015  *
2016  * The optional $resetGzipEncoding parameter controls suppression of
2017  * the Content-Encoding header sent by ob_gzhandler; by default it
2018  * is left. See comments for wfClearOutputBuffers() for why it would
2019  * be used.
2020  *
2021  * Note that some PHP configuration options may add output buffer
2022  * layers which cannot be removed; these are left in place.
2023  *
2024  * @param $resetGzipEncoding Bool
2025  */
2026 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
2027         if( $resetGzipEncoding ) {
2028                 // Suppress Content-Encoding and Content-Length
2029                 // headers from 1.10+s wfOutputHandler
2030                 global $wgDisableOutputCompression;
2031                 $wgDisableOutputCompression = true;
2032         }
2033         while( $status = ob_get_status() ) {
2034                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
2035                         // Probably from zlib.output_compression or other
2036                         // PHP-internal setting which can't be removed.
2037                         //
2038                         // Give up, and hope the result doesn't break
2039                         // output behavior.
2040                         break;
2041                 }
2042                 if( !ob_end_clean() ) {
2043                         // Could not remove output buffer handler; abort now
2044                         // to avoid getting in some kind of infinite loop.
2045                         break;
2046                 }
2047                 if( $resetGzipEncoding ) {
2048                         if( $status['name'] == 'ob_gzhandler' ) {
2049                                 // Reset the 'Content-Encoding' field set by this handler
2050                                 // so we can start fresh.
2051                                 if ( function_exists( 'header_remove' ) ) {
2052                                         // Available since PHP 5.3.0
2053                                         header_remove( 'Content-Encoding' );
2054                                 } else {
2055                                         // We need to provide a valid content-coding. See bug 28069
2056                                         header( 'Content-Encoding: identity' );
2057                                 }
2058                                 break;
2059                         }
2060                 }
2061         }
2062 }
2063
2064 /**
2065  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
2066  *
2067  * Clear away output buffers, but keep the Content-Encoding header
2068  * produced by ob_gzhandler, if any.
2069  *
2070  * This should be used for HTTP 304 responses, where you need to
2071  * preserve the Content-Encoding header of the real result, but
2072  * also need to suppress the output of ob_gzhandler to keep to spec
2073  * and avoid breaking Firefox in rare cases where the headers and
2074  * body are broken over two packets.
2075  */
2076 function wfClearOutputBuffers() {
2077         wfResetOutputBuffers( false );
2078 }
2079
2080 /**
2081  * Converts an Accept-* header into an array mapping string values to quality
2082  * factors
2083  *
2084  * @param $accept String
2085  * @param $def String default
2086  * @return Array
2087  */
2088 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
2089         # No arg means accept anything (per HTTP spec)
2090         if( !$accept ) {
2091                 return array( $def => 1.0 );
2092         }
2093
2094         $prefs = array();
2095
2096         $parts = explode( ',', $accept );
2097
2098         foreach( $parts as $part ) {
2099                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
2100                 $values = explode( ';', trim( $part ) );
2101                 $match = array();
2102                 if ( count( $values ) == 1 ) {
2103                         $prefs[$values[0]] = 1.0;
2104                 } elseif ( preg_match( '/q\s*=\s*(\d*\.\d+)/', $values[1], $match ) ) {
2105                         $prefs[$values[0]] = floatval( $match[1] );
2106                 }
2107         }
2108
2109         return $prefs;
2110 }
2111
2112 /**
2113  * Checks if a given MIME type matches any of the keys in the given
2114  * array. Basic wildcards are accepted in the array keys.
2115  *
2116  * Returns the matching MIME type (or wildcard) if a match, otherwise
2117  * NULL if no match.
2118  *
2119  * @param $type String
2120  * @param $avail Array
2121  * @return string
2122  * @private
2123  */
2124 function mimeTypeMatch( $type, $avail ) {
2125         if( array_key_exists( $type, $avail ) ) {
2126                 return $type;
2127         } else {
2128                 $parts = explode( '/', $type );
2129                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
2130                         return $parts[0] . '/*';
2131                 } elseif( array_key_exists( '*/*', $avail ) ) {
2132                         return '*/*';
2133                 } else {
2134                         return null;
2135                 }
2136         }
2137 }
2138
2139 /**
2140  * Returns the 'best' match between a client's requested internet media types
2141  * and the server's list of available types. Each list should be an associative
2142  * array of type to preference (preference is a float between 0.0 and 1.0).
2143  * Wildcards in the types are acceptable.
2144  *
2145  * @param $cprefs Array: client's acceptable type list
2146  * @param $sprefs Array: server's offered types
2147  * @return string
2148  *
2149  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
2150  * XXX: generalize to negotiate other stuff
2151  */
2152 function wfNegotiateType( $cprefs, $sprefs ) {
2153         $combine = array();
2154
2155         foreach( array_keys($sprefs) as $type ) {
2156                 $parts = explode( '/', $type );
2157                 if( $parts[1] != '*' ) {
2158                         $ckey = mimeTypeMatch( $type, $cprefs );
2159                         if( $ckey ) {
2160                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
2161                         }
2162                 }
2163         }
2164
2165         foreach( array_keys( $cprefs ) as $type ) {
2166                 $parts = explode( '/', $type );
2167                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
2168                         $skey = mimeTypeMatch( $type, $sprefs );
2169                         if( $skey ) {
2170                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
2171                         }
2172                 }
2173         }
2174
2175         $bestq = 0;
2176         $besttype = null;
2177
2178         foreach( array_keys( $combine ) as $type ) {
2179                 if( $combine[$type] > $bestq ) {
2180                         $besttype = $type;
2181                         $bestq = $combine[$type];
2182                 }
2183         }
2184
2185         return $besttype;
2186 }
2187
2188 /**
2189  * Reference-counted warning suppression
2190  *
2191  * @param $end Bool
2192  */
2193 function wfSuppressWarnings( $end = false ) {
2194         static $suppressCount = 0;
2195         static $originalLevel = false;
2196
2197         if ( $end ) {
2198                 if ( $suppressCount ) {
2199                         --$suppressCount;
2200                         if ( !$suppressCount ) {
2201                                 error_reporting( $originalLevel );
2202                         }
2203                 }
2204         } else {
2205                 if ( !$suppressCount ) {
2206                         // E_DEPRECATED is undefined in PHP 5.2
2207                         if( !defined( 'E_DEPRECATED' ) ){
2208                                 define( 'E_DEPRECATED', 8192 );
2209                         }
2210                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE | E_USER_WARNING | E_USER_NOTICE | E_DEPRECATED ) );
2211                 }
2212                 ++$suppressCount;
2213         }
2214 }
2215
2216 /**
2217  * Restore error level to previous value
2218  */
2219 function wfRestoreWarnings() {
2220         wfSuppressWarnings( true );
2221 }
2222
2223 # Autodetect, convert and provide timestamps of various types
2224
2225 /**
2226  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
2227  */
2228 define( 'TS_UNIX', 0 );
2229
2230 /**
2231  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
2232  */
2233 define( 'TS_MW', 1 );
2234
2235 /**
2236  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
2237  */
2238 define( 'TS_DB', 2 );
2239
2240 /**
2241  * RFC 2822 format, for E-mail and HTTP headers
2242  */
2243 define( 'TS_RFC2822', 3 );
2244
2245 /**
2246  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
2247  *
2248  * This is used by Special:Export
2249  */
2250 define( 'TS_ISO_8601', 4 );
2251
2252 /**
2253  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
2254  *
2255  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
2256  *       DateTime tag and page 36 for the DateTimeOriginal and
2257  *       DateTimeDigitized tags.
2258  */
2259 define( 'TS_EXIF', 5 );
2260
2261 /**
2262  * Oracle format time.
2263  */
2264 define( 'TS_ORACLE', 6 );
2265
2266 /**
2267  * Postgres format time.
2268  */
2269 define( 'TS_POSTGRES', 7 );
2270
2271 /**
2272  * DB2 format time
2273  */
2274 define( 'TS_DB2', 8 );
2275
2276 /**
2277  * ISO 8601 basic format with no timezone: 19860209T200000Z.  This is used by ResourceLoader
2278  */
2279 define( 'TS_ISO_8601_BASIC', 9 );
2280
2281 /**
2282  * Get a timestamp string in one of various formats
2283  *
2284  * @param $outputtype Mixed: A timestamp in one of the supported formats, the
2285  *                    function will autodetect which format is supplied and act
2286  *                    accordingly.
2287  * @param $ts Mixed: the timestamp to convert or 0 for the current timestamp
2288  * @return Mixed: String / false The same date in the format specified in $outputtype or false
2289  */
2290 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
2291         $uts = 0;
2292         $da = array();
2293         $strtime = '';
2294
2295         if ( !$ts ) { // We want to catch 0, '', null... but not date strings starting with a letter.
2296                 $uts = time();
2297                 $strtime = "@$uts";
2298         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2299                 # TS_DB
2300         } elseif ( preg_match( '/^(\d{4}):(\d\d):(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2301                 # TS_EXIF
2302         } elseif ( preg_match( '/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/D', $ts, $da ) ) {
2303                 # TS_MW
2304         } elseif ( preg_match( '/^-?\d{1,13}$/D', $ts ) ) {
2305                 # TS_UNIX
2306                 $uts = $ts;
2307                 $strtime = "@$ts"; // Undocumented?
2308         } elseif ( preg_match( '/^\d{2}-\d{2}-\d{4} \d{2}:\d{2}:\d{2}.\d{6}$/', $ts ) ) {
2309                 # TS_ORACLE // session altered to DD-MM-YYYY HH24:MI:SS.FF6
2310                 $strtime = preg_replace( '/(\d\d)\.(\d\d)\.(\d\d)(\.(\d+))?/', "$1:$2:$3",
2311                                 str_replace( '+00:00', 'UTC', $ts ) );
2312         } elseif ( preg_match( '/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2313                 # TS_ISO_8601
2314         } elseif ( preg_match( '/^(\d{4})(\d{2})(\d{2})T(\d{2})(\d{2})(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2315                 #TS_ISO_8601_BASIC
2316         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d*[\+\- ](\d\d)$/', $ts, $da ) ) {
2317                 # TS_POSTGRES
2318         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d* GMT$/', $ts, $da ) ) {
2319                 # TS_POSTGRES
2320         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.\d\d\d$/',$ts,$da)) {
2321                 # TS_DB2
2322         } elseif ( preg_match( '/^[ \t\r\n]*([A-Z][a-z]{2},[ \t\r\n]*)?' . # Day of week
2323                                                         '\d\d?[ \t\r\n]*[A-Z][a-z]{2}[ \t\r\n]*\d{2}(?:\d{2})?' .  # dd Mon yyyy
2324                                                         '[ \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
2325                 # TS_RFC2822, accepting a trailing comment. See http://www.squid-cache.org/mail-archive/squid-users/200307/0122.html / r77171
2326                 # The regex is a superset of rfc2822 for readability
2327                 $strtime = strtok( $ts, ';' );
2328         } 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 ) ) {
2329                 # TS_RFC850
2330                 $strtime = $ts;
2331         } 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 ) ) {
2332                 # asctime
2333                 $strtime = $ts;
2334         } else {
2335                 # Bogus value...
2336                 wfDebug("wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n");
2337
2338                 return false;
2339         }
2340
2341         static $formats = array(
2342                 TS_UNIX => 'U',
2343                 TS_MW => 'YmdHis',
2344                 TS_DB => 'Y-m-d H:i:s',
2345                 TS_ISO_8601 => 'Y-m-d\TH:i:s\Z',
2346                 TS_ISO_8601_BASIC => 'Ymd\THis\Z',
2347                 TS_EXIF => 'Y:m:d H:i:s', // This shouldn't ever be used, but is included for completeness
2348                 TS_RFC2822 => 'D, d M Y H:i:s',
2349                 TS_ORACLE => 'd-m-Y H:i:s.000000', // Was 'd-M-y h.i.s A' . ' +00:00' before r51500
2350                 TS_POSTGRES => 'Y-m-d H:i:s',
2351                 TS_DB2 => 'Y-m-d H:i:s',
2352         );
2353
2354         if ( !isset( $formats[$outputtype] ) ) {
2355                 throw new MWException( 'wfTimestamp() called with illegal output type.' );
2356         }
2357
2358         if ( function_exists( "date_create" ) ) {
2359                 if ( count( $da ) ) {
2360                         $ds = sprintf("%04d-%02d-%02dT%02d:%02d:%02d.00+00:00",
2361                                 (int)$da[1], (int)$da[2], (int)$da[3],
2362                                 (int)$da[4], (int)$da[5], (int)$da[6]);
2363
2364                         $d = date_create( $ds, new DateTimeZone( 'GMT' ) );
2365                 } elseif ( $strtime ) {
2366                         $d = date_create( $strtime, new DateTimeZone( 'GMT' ) );
2367                 } else {
2368                         return false;
2369                 }
2370
2371                 if ( !$d ) {
2372                         wfDebug("wfTimestamp() fed bogus time value: $outputtype; $ts\n");
2373                         return false;
2374                 }
2375
2376                 $output = $d->format( $formats[$outputtype] );
2377         } else {
2378                 if ( count( $da ) ) {
2379                         // Warning! gmmktime() acts oddly if the month or day is set to 0
2380                         // We may want to handle that explicitly at some point
2381                         $uts = gmmktime( (int)$da[4], (int)$da[5], (int)$da[6],
2382                                 (int)$da[2], (int)$da[3], (int)$da[1] );
2383                 } elseif ( $strtime ) {
2384                         $uts = strtotime( $strtime );
2385                 }
2386
2387                 if ( $uts === false ) {
2388                         wfDebug("wfTimestamp() can't parse the timestamp (non 32-bit time? Update php): $outputtype; $ts\n");
2389                         return false;
2390                 }
2391
2392                 if ( TS_UNIX == $outputtype ) {
2393                         return $uts;
2394                 }
2395                 $output = gmdate( $formats[$outputtype], $uts );
2396         }
2397
2398         if ( ( $outputtype == TS_RFC2822 ) || ( $outputtype == TS_POSTGRES ) ) {
2399                 $output .= ' GMT';
2400         }
2401
2402         return $output;
2403 }
2404
2405 /**
2406  * Return a formatted timestamp, or null if input is null.
2407  * For dealing with nullable timestamp columns in the database.
2408  *
2409  * @param $outputtype Integer
2410  * @param $ts String
2411  * @return String
2412  */
2413 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2414         if( is_null( $ts ) ) {
2415                 return null;
2416         } else {
2417                 return wfTimestamp( $outputtype, $ts );
2418         }
2419 }
2420
2421 /**
2422  * Convenience function; returns MediaWiki timestamp for the present time.
2423  *
2424  * @return string
2425  */
2426 function wfTimestampNow() {
2427         # return NOW
2428         return wfTimestamp( TS_MW, time() );
2429 }
2430
2431 /**
2432  * Check if the operating system is Windows
2433  *
2434  * @return Bool: true if it's Windows, False otherwise.
2435  */
2436 function wfIsWindows() {
2437         static $isWindows = null;
2438         if ( $isWindows === null ) {
2439                 $isWindows = substr( php_uname(), 0, 7 ) == 'Windows';
2440         }
2441         return $isWindows;
2442 }
2443
2444 /**
2445  * Check if we are running under HipHop
2446  *
2447  * @return Bool
2448  */
2449 function wfIsHipHop() {
2450         return function_exists( 'hphp_thread_set_warmup_enabled' );
2451 }
2452
2453 /**
2454  * Swap two variables
2455  *
2456  * @param $x Mixed
2457  * @param $y Mixed
2458  */
2459 function swap( &$x, &$y ) {
2460         $z = $x;
2461         $x = $y;
2462         $y = $z;
2463 }
2464
2465 /**
2466  * Tries to get the system directory for temporary files. The TMPDIR, TMP, and
2467  * TEMP environment variables are then checked in sequence, and if none are set
2468  * try sys_get_temp_dir() for PHP >= 5.2.1. All else fails, return /tmp for Unix
2469  * or C:\Windows\Temp for Windows and hope for the best.
2470  * It is common to call it with tempnam().
2471  *
2472  * NOTE: When possible, use instead the tmpfile() function to create
2473  * temporary files to avoid race conditions on file creation, etc.
2474  *
2475  * @return String
2476  */
2477 function wfTempDir() {
2478         foreach( array( 'TMPDIR', 'TMP', 'TEMP' ) as $var ) {
2479                 $tmp = getenv( $var );
2480                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
2481                         return $tmp;
2482                 }
2483         }
2484         if( function_exists( 'sys_get_temp_dir' ) ) {
2485                 return sys_get_temp_dir();
2486         }
2487         # Usual defaults
2488         return wfIsWindows() ? 'C:\Windows\Temp' : '/tmp';
2489 }
2490
2491 /**
2492  * Make directory, and make all parent directories if they don't exist
2493  *
2494  * @param $dir String: full path to directory to create
2495  * @param $mode Integer: chmod value to use, default is $wgDirectoryMode
2496  * @param $caller String: optional caller param for debugging.
2497  * @return bool
2498  */
2499 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2500         global $wgDirectoryMode;
2501
2502         if ( !is_null( $caller ) ) {
2503                 wfDebug( "$caller: called wfMkdirParents($dir)" );
2504         }
2505
2506         if( strval( $dir ) === '' || file_exists( $dir ) ) {
2507                 return true;
2508         }
2509
2510         $dir = str_replace( array( '\\', '/' ), DIRECTORY_SEPARATOR, $dir );
2511
2512         if ( is_null( $mode ) ) {
2513                 $mode = $wgDirectoryMode;
2514         }
2515
2516         // Turn off the normal warning, we're doing our own below
2517         wfSuppressWarnings();
2518         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2519         wfRestoreWarnings();
2520
2521         if( !$ok ) {
2522                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2523                 trigger_error( __FUNCTION__ . ": failed to mkdir \"$dir\" mode $mode", E_USER_WARNING );
2524         }
2525         return $ok;
2526 }
2527
2528 /**
2529  * Increment a statistics counter
2530  *
2531  * @param $key String
2532  * @param $count Int
2533  */
2534 function wfIncrStats( $key, $count = 1 ) {
2535         global $wgStatsMethod;
2536
2537         $count = intval( $count );
2538
2539         if( $wgStatsMethod == 'udp' ) {
2540                 global $wgUDPProfilerHost, $wgUDPProfilerPort, $wgDBname, $wgAggregateStatsID;
2541                 static $socket;
2542
2543                 $id = $wgAggregateStatsID !== false ? $wgAggregateStatsID : $wgDBname;
2544
2545                 if ( !$socket ) {
2546                         $socket = socket_create( AF_INET, SOCK_DGRAM, SOL_UDP );
2547                         $statline = "stats/{$id} - {$count} 1 1 1 1 -total\n";
2548                         socket_sendto(
2549                                 $socket,
2550                                 $statline,
2551                                 strlen( $statline ),
2552                                 0,
2553                                 $wgUDPProfilerHost,
2554                                 $wgUDPProfilerPort
2555                         );
2556                 }
2557                 $statline = "stats/{$id} - {$count} 1 1 1 1 {$key}\n";
2558                 wfSuppressWarnings();
2559                 socket_sendto(
2560                         $socket,
2561                         $statline,
2562                         strlen( $statline ),
2563                         0,
2564                         $wgUDPProfilerHost,
2565                         $wgUDPProfilerPort
2566                 );
2567                 wfRestoreWarnings();
2568         } elseif( $wgStatsMethod == 'cache' ) {
2569                 global $wgMemc;
2570                 $key = wfMemcKey( 'stats', $key );
2571                 if ( is_null( $wgMemc->incr( $key, $count ) ) ) {
2572                         $wgMemc->add( $key, $count );
2573                 }
2574         } else {
2575                 // Disabled
2576         }
2577 }
2578
2579 /**
2580  * @param $nr Mixed: the number to format
2581  * @param $acc Integer: the number of digits after the decimal point, default 2
2582  * @param $round Boolean: whether or not to round the value, default true
2583  * @return float
2584  */
2585 function wfPercent( $nr, $acc = 2, $round = true ) {
2586         $ret = sprintf( "%.${acc}f", $nr );
2587         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2588 }
2589
2590 /**
2591  * Find out whether or not a mixed variable exists in a string
2592  *
2593  * @param $needle String
2594  * @param $str String
2595  * @param $insensitive Boolean
2596  * @return Boolean
2597  */
2598 function in_string( $needle, $str, $insensitive = false ) {
2599         $func = 'strpos';
2600         if( $insensitive ) $func = 'stripos';
2601
2602         return $func( $str, $needle ) !== false;
2603 }
2604
2605 /**
2606  * Make a list item, used by various special pages
2607  *
2608  * @param $page String Page link
2609  * @param $details String Text between brackets
2610  * @param $oppositedm Boolean   Add the direction mark opposite to your
2611  *                                                              language, to display text properly
2612  * @return String
2613  */
2614 function wfSpecialList( $page, $details, $oppositedm = true ) {
2615         global $wgLang;
2616         $dirmark = ( $oppositedm ? $wgLang->getDirMark( true ) : '' ) .
2617                 $wgLang->getDirMark();
2618         $details = $details ? $dirmark . " ($details)" : '';
2619         return $page . $details;
2620 }
2621
2622 /**
2623  * Safety wrapper around ini_get() for boolean settings.
2624  * The values returned from ini_get() are pre-normalized for settings
2625  * set via php.ini or php_flag/php_admin_flag... but *not*
2626  * for those set via php_value/php_admin_value.
2627  *
2628  * It's fairly common for people to use php_value instead of php_flag,
2629  * which can leave you with an 'off' setting giving a false positive
2630  * for code that just takes the ini_get() return value as a boolean.
2631  *
2632  * To make things extra interesting, setting via php_value accepts
2633  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2634  * Unrecognized values go false... again opposite PHP's own coercion
2635  * from string to bool.
2636  *
2637  * Luckily, 'properly' set settings will always come back as '0' or '1',
2638  * so we only have to worry about them and the 'improper' settings.
2639  *
2640  * I frickin' hate PHP... :P
2641  *
2642  * @param $setting String
2643  * @return Bool
2644  */
2645 function wfIniGetBool( $setting ) {
2646         $val = ini_get( $setting );
2647         // 'on' and 'true' can't have whitespace around them, but '1' can.
2648         return strtolower( $val ) == 'on'
2649                 || strtolower( $val ) == 'true'
2650                 || strtolower( $val ) == 'yes'
2651                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2652 }
2653
2654 /**
2655  * Wrapper function for PHP's dl(). This doesn't work in most situations from
2656  * PHP 5.3 onward, and is usually disabled in shared environments anyway.
2657  *
2658  * @param $extension String A PHP extension. The file suffix (.so or .dll)
2659  *                          should be omitted
2660  * @param $fileName String Name of the library, if not $extension.suffix
2661  * @return Bool - Whether or not the extension is loaded
2662  */
2663 function wfDl( $extension, $fileName = null ) {
2664         if( extension_loaded( $extension ) ) {
2665                 return true;
2666         }
2667
2668         $canDl = false;
2669         $sapi = php_sapi_name();
2670         if( version_compare( PHP_VERSION, '5.3.0', '<' ) ||
2671                 $sapi == 'cli' || $sapi == 'cgi' || $sapi == 'embed' )
2672         {
2673                 $canDl = ( function_exists( 'dl' ) && is_callable( 'dl' )
2674                 && wfIniGetBool( 'enable_dl' ) && !wfIniGetBool( 'safe_mode' ) );
2675         }
2676
2677         if( $canDl ) {
2678                 $fileName = $fileName ? $fileName : $extension;
2679                 if( wfIsWindows() ) {
2680                         $fileName = 'php_' . $fileName;
2681                 }
2682                 wfSuppressWarnings();
2683                 dl( $fileName . '.' . PHP_SHLIB_SUFFIX );
2684                 wfRestoreWarnings();
2685         }
2686         return extension_loaded( $extension );
2687 }
2688
2689 /**
2690  * Execute a shell command, with time and memory limits mirrored from the PHP
2691  * configuration if supported.
2692  * @param $cmd String Command line, properly escaped for shell.
2693  * @param &$retval optional, will receive the program's exit code.
2694  *                 (non-zero is usually failure)
2695  * @param $environ Array optional environment variables which should be
2696  *                 added to the executed command environment.
2697  * @return collected stdout as a string (trailing newlines stripped)
2698  */
2699 function wfShellExec( $cmd, &$retval = null, $environ = array() ) {
2700         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize, $wgMaxShellTime;
2701
2702         static $disabled;
2703         if ( is_null( $disabled ) ) {
2704                 $disabled = false;
2705                 if( wfIniGetBool( 'safe_mode' ) ) {
2706                         wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
2707                         $disabled = 'safemode';
2708                 } else {
2709                         $functions = explode( ',', ini_get( 'disable_functions' ) );
2710                         $functions = array_map( 'trim', $functions );
2711                         $functions = array_map( 'strtolower', $functions );
2712                         if ( in_array( 'passthru', $functions ) ) {
2713                                 wfDebug( "passthru is in disabled_functions\n" );
2714                                 $disabled = 'passthru';
2715                         }
2716                 }
2717         }
2718         if ( $disabled ) {
2719                 $retval = 1;
2720                 return $disabled == 'safemode' ?
2721                         'Unable to run external programs in safe mode.' :
2722                         'Unable to run external programs, passthru() is disabled.';
2723         }
2724
2725         wfInitShellLocale();
2726
2727         $envcmd = '';
2728         foreach( $environ as $k => $v ) {
2729                 if ( wfIsWindows() ) {
2730                         /* Surrounding a set in quotes (method used by wfEscapeShellArg) makes the quotes themselves
2731                          * appear in the environment variable, so we must use carat escaping as documented in
2732                          * http://technet.microsoft.com/en-us/library/cc723564.aspx
2733                          * Note however that the quote isn't listed there, but is needed, and the parentheses
2734                          * are listed there but doesn't appear to need it.
2735                          */
2736                         $envcmd .= "set $k=" . preg_replace( '/([&|()<>^"])/', '^\\1', $v ) . '&& ';
2737                 } else {
2738                         /* Assume this is a POSIX shell, thus required to accept variable assignments before the command
2739                          * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_09_01
2740                          */
2741                         $envcmd .= "$k=" . escapeshellarg( $v ) . ' ';
2742                 }
2743         }
2744         $cmd = $envcmd . $cmd;
2745
2746         if ( wfIsWindows() ) {
2747                 if ( version_compare( PHP_VERSION, '5.3.0', '<' ) && /* Fixed in 5.3.0 :) */
2748                         ( version_compare( PHP_VERSION, '5.2.1', '>=' ) || php_uname( 's' ) == 'Windows NT' ) )
2749                 {
2750                         # Hack to work around PHP's flawed invocation of cmd.exe
2751                         # http://news.php.net/php.internals/21796
2752                         # Windows 9x doesn't accept any kind of quotes
2753                         $cmd = '"' . $cmd . '"';
2754                 }
2755         } elseif ( php_uname( 's' ) == 'Linux' ) {
2756                 $time = intval( $wgMaxShellTime );
2757                 $mem = intval( $wgMaxShellMemory );
2758                 $filesize = intval( $wgMaxShellFileSize );
2759
2760                 if ( $time > 0 && $mem > 0 ) {
2761                         $script = "$IP/bin/ulimit4.sh";
2762                         if ( is_executable( $script ) ) {
2763                                 $cmd = '/bin/bash ' . escapeshellarg( $script ) . " $time $mem $filesize " . escapeshellarg( $cmd );
2764                         }
2765                 }
2766         }
2767         wfDebug( "wfShellExec: $cmd\n" );
2768
2769         $retval = 1; // error by default?
2770         ob_start();
2771         passthru( $cmd, $retval );
2772         $output = ob_get_contents();
2773         ob_end_clean();
2774
2775         if ( $retval == 127 ) {
2776                 wfDebugLog( 'exec', "Possibly missing executable file: $cmd\n" );
2777         }
2778         return $output;
2779 }
2780
2781 /**
2782  * Workaround for http://bugs.php.net/bug.php?id=45132
2783  * escapeshellarg() destroys non-ASCII characters if LANG is not a UTF-8 locale
2784  */
2785 function wfInitShellLocale() {
2786         static $done = false;
2787         if ( $done ) {
2788                 return;
2789         }
2790         $done = true;
2791         global $wgShellLocale;
2792         if ( !wfIniGetBool( 'safe_mode' ) ) {
2793                 putenv( "LC_CTYPE=$wgShellLocale" );
2794                 setlocale( LC_CTYPE, $wgShellLocale );
2795         }
2796 }
2797
2798 /**
2799  * This function works like "use VERSION" in Perl, the program will die with a
2800  * backtrace if the current version of PHP is less than the version provided
2801  *
2802  * This is useful for extensions which due to their nature are not kept in sync
2803  * with releases, and might depend on other versions of PHP than the main code
2804  *
2805  * Note: PHP might die due to parsing errors in some cases before it ever
2806  *       manages to call this function, such is life
2807  *
2808  * @see perldoc -f use
2809  *
2810  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2811  *                 a float
2812  */
2813 function wfUsePHP( $req_ver ) {
2814         $php_ver = PHP_VERSION;
2815
2816         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
2817                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
2818         }
2819 }
2820
2821 /**
2822  * This function works like "use VERSION" in Perl except it checks the version
2823  * of MediaWiki, the program will die with a backtrace if the current version
2824  * of MediaWiki is less than the version provided.
2825  *
2826  * This is useful for extensions which due to their nature are not kept in sync
2827  * with releases
2828  *
2829  * @see perldoc -f use
2830  *
2831  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2832  *                 a float
2833  */
2834 function wfUseMW( $req_ver ) {
2835         global $wgVersion;
2836
2837         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
2838                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
2839         }
2840 }
2841
2842 /**
2843  * Return the final portion of a pathname.
2844  * Reimplemented because PHP5's basename() is buggy with multibyte text.
2845  * http://bugs.php.net/bug.php?id=33898
2846  *
2847  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
2848  * We'll consider it so always, as we don't want \s in our Unix paths either.
2849  *
2850  * @param $path String
2851  * @param $suffix String: to remove if present
2852  * @return String
2853  */
2854 function wfBaseName( $path, $suffix = '' ) {
2855         $encSuffix = ( $suffix == '' )
2856                 ? ''
2857                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
2858         $matches = array();
2859         if( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2860                 return $matches[1];
2861         } else {
2862                 return '';
2863         }
2864 }
2865
2866 /**
2867  * Generate a relative path name to the given file.
2868  * May explode on non-matching case-insensitive paths,
2869  * funky symlinks, etc.
2870  *
2871  * @param $path String: absolute destination path including target filename
2872  * @param $from String: Absolute source path, directory only
2873  * @return String
2874  */
2875 function wfRelativePath( $path, $from ) {
2876         // Normalize mixed input on Windows...
2877         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2878         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2879
2880         // Trim trailing slashes -- fix for drive root
2881         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2882         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2883
2884         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2885         $against = explode( DIRECTORY_SEPARATOR, $from );
2886
2887         if( $pieces[0] !== $against[0] ) {
2888                 // Non-matching Windows drive letters?
2889                 // Return a full path.
2890                 return $path;
2891         }
2892
2893         // Trim off common prefix
2894         while( count( $pieces ) && count( $against )
2895                 && $pieces[0] == $against[0] ) {
2896                 array_shift( $pieces );
2897                 array_shift( $against );
2898         }
2899
2900         // relative dots to bump us to the parent
2901         while( count( $against ) ) {
2902                 array_unshift( $pieces, '..' );
2903                 array_shift( $against );
2904         }
2905
2906         array_push( $pieces, wfBaseName( $path ) );
2907
2908         return implode( DIRECTORY_SEPARATOR, $pieces );
2909 }
2910
2911 /**
2912  * Do any deferred updates and clear the list
2913  *
2914  * @param $commit String: set to 'commit' to commit after every update to
2915  *                prevent lock contention
2916  */
2917 function wfDoUpdates( $commit = '' ) {
2918         global $wgDeferredUpdateList;
2919
2920         wfProfileIn( __METHOD__ );
2921
2922         // No need to get master connections in case of empty updates array
2923         if ( !count( $wgDeferredUpdateList ) ) {
2924                 wfProfileOut( __METHOD__ );
2925                 return;
2926         }
2927
2928         $doCommit = $commit == 'commit';
2929         if ( $doCommit ) {
2930                 $dbw = wfGetDB( DB_MASTER );
2931         }
2932
2933         foreach ( $wgDeferredUpdateList as $update ) {
2934                 $update->doUpdate();
2935
2936                 if ( $doCommit && $dbw->trxLevel() ) {
2937                         $dbw->commit();
2938                 }
2939         }
2940
2941         $wgDeferredUpdateList = array();
2942         wfProfileOut( __METHOD__ );
2943 }
2944
2945 /**
2946  * Convert an arbitrarily-long digit string from one numeric base
2947  * to another, optionally zero-padding to a minimum column width.
2948  *
2949  * Supports base 2 through 36; digit values 10-36 are represented
2950  * as lowercase letters a-z. Input is case-insensitive.
2951  *
2952  * @param $input String: of digits
2953  * @param $sourceBase Integer: 2-36
2954  * @param $destBase Integer: 2-36
2955  * @param $pad Integer: 1 or greater
2956  * @param $lowercase Boolean
2957  * @return String or false on invalid input
2958  */
2959 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1, $lowercase = true ) {
2960         $input = strval( $input );
2961         if( $sourceBase < 2 ||
2962                 $sourceBase > 36 ||
2963                 $destBase < 2 ||
2964                 $destBase > 36 ||
2965                 $pad < 1 ||
2966                 $sourceBase != intval( $sourceBase ) ||
2967                 $destBase != intval( $destBase ) ||
2968                 $pad != intval( $pad ) ||
2969                 !is_string( $input ) ||
2970                 $input == '' ) {
2971                 return false;
2972         }
2973         $digitChars = ( $lowercase ) ? '0123456789abcdefghijklmnopqrstuvwxyz' : '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
2974         $inDigits = array();
2975         $outChars = '';
2976
2977         // Decode and validate input string
2978         $input = strtolower( $input );
2979         for( $i = 0; $i < strlen( $input ); $i++ ) {
2980                 $n = strpos( $digitChars, $input[$i] );
2981                 if( $n === false || $n > $sourceBase ) {
2982                         return false;
2983                 }
2984                 $inDigits[] = $n;
2985         }
2986
2987         // Iterate over the input, modulo-ing out an output digit
2988         // at a time until input is gone.
2989         while( count( $inDigits ) ) {
2990                 $work = 0;
2991                 $workDigits = array();
2992
2993                 // Long division...
2994                 foreach( $inDigits as $digit ) {
2995                         $work *= $sourceBase;
2996                         $work += $digit;
2997
2998                         if( $work < $destBase ) {
2999                                 // Gonna need to pull another digit.
3000                                 if( count( $workDigits ) ) {
3001                                         // Avoid zero-padding; this lets us find
3002                                         // the end of the input very easily when
3003                                         // length drops to zero.
3004                                         $workDigits[] = 0;
3005                                 }
3006                         } else {
3007                                 // Finally! Actual division!
3008                                 $workDigits[] = intval( $work / $destBase );
3009
3010                                 // Isn't it annoying that most programming languages
3011                                 // don't have a single divide-and-remainder operator,
3012                                 // even though the CPU implements it that way?
3013                                 $work = $work % $destBase;
3014                         }
3015                 }
3016
3017                 // All that division leaves us with a remainder,
3018                 // which is conveniently our next output digit.
3019                 $outChars .= $digitChars[$work];
3020
3021                 // And we continue!
3022                 $inDigits = $workDigits;
3023         }
3024
3025         while( strlen( $outChars ) < $pad ) {
3026                 $outChars .= '0';
3027         }
3028
3029         return strrev( $outChars );
3030 }
3031
3032 /**
3033  * Create an object with a given name and an array of construct parameters
3034  *
3035  * @param $name String
3036  * @param $p Array: parameters
3037  * @deprecated since 1.18, warnings in 1.18, removal in 1.20
3038  */
3039 function wfCreateObject( $name, $p ) {
3040         wfDeprecated( __FUNCTION__ );
3041         return MWFunction::newObj( $name, $p );
3042 }
3043
3044 function wfHttpOnlySafe() {
3045         global $wgHttpOnlyBlacklist;
3046
3047         if( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
3048                 foreach( $wgHttpOnlyBlacklist as $regex ) {
3049                         if( preg_match( $regex, $_SERVER['HTTP_USER_AGENT'] ) ) {
3050                                 return false;
3051                         }
3052                 }
3053         }
3054
3055         return true;
3056 }
3057
3058 /**
3059  * Initialise php session
3060  *
3061  * @param $sessionId Bool
3062  */
3063 function wfSetupSession( $sessionId = false ) {
3064         global $wgSessionsInMemcached, $wgCookiePath, $wgCookieDomain,
3065                         $wgCookieSecure, $wgCookieHttpOnly, $wgSessionHandler;
3066         if( $wgSessionsInMemcached ) {
3067                 if ( !defined( 'MW_COMPILED' ) ) {
3068                         global $IP;
3069                         require_once( "$IP/includes/cache/MemcachedSessions.php" );
3070                 }
3071                 session_set_save_handler( 'memsess_open', 'memsess_close', 'memsess_read',
3072                         'memsess_write', 'memsess_destroy', 'memsess_gc' );
3073
3074                 // It's necessary to register a shutdown function to call session_write_close(),
3075                 // because by the time the request shutdown function for the session module is
3076                 // called, $wgMemc has already been destroyed. Shutdown functions registered
3077                 // this way are called before object destruction.
3078                 register_shutdown_function( 'memsess_write_close' );
3079         } elseif( $wgSessionHandler && $wgSessionHandler != ini_get( 'session.save_handler' ) ) {
3080                 # Only set this if $wgSessionHandler isn't null and session.save_handler
3081                 # hasn't already been set to the desired value (that causes errors)
3082                 ini_set( 'session.save_handler', $wgSessionHandler );
3083         }
3084         $httpOnlySafe = wfHttpOnlySafe() && $wgCookieHttpOnly;
3085         wfDebugLog( 'cookie',
3086                 'session_set_cookie_params: "' . implode( '", "',
3087                         array(
3088                                 0,
3089                                 $wgCookiePath,
3090                                 $wgCookieDomain,
3091                                 $wgCookieSecure,
3092                                 $httpOnlySafe ) ) . '"' );
3093         session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $httpOnlySafe );
3094         session_cache_limiter( 'private, must-revalidate' );
3095         if ( $sessionId ) {
3096                 session_id( $sessionId );
3097         }
3098         wfSuppressWarnings();
3099         session_start();
3100         wfRestoreWarnings();
3101 }
3102
3103 /**
3104  * Get an object from the precompiled serialized directory
3105  *
3106  * @param $name String
3107  * @return Mixed: the variable on success, false on failure
3108  */
3109 function wfGetPrecompiledData( $name ) {
3110         global $IP;
3111
3112         $file = "$IP/serialized/$name";
3113         if ( file_exists( $file ) ) {
3114                 $blob = file_get_contents( $file );
3115                 if ( $blob ) {
3116                         return unserialize( $blob );
3117                 }
3118         }
3119         return false;
3120 }
3121
3122 /**
3123  * Get a cache key
3124  *
3125  * @param varargs
3126  * @return String
3127  */
3128 function wfMemcKey( /*... */ ) {
3129         $args = func_get_args();
3130         $key = wfWikiID() . ':' . implode( ':', $args );
3131         $key = str_replace( ' ', '_', $key );
3132         return $key;
3133 }
3134
3135 /**
3136  * Get a cache key for a foreign DB
3137  *
3138  * @param $db String
3139  * @param $prefix String
3140  * @param varargs String
3141  * @return String
3142  */
3143 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
3144         $args = array_slice( func_get_args(), 2 );
3145         if ( $prefix ) {
3146                 $key = "$db-$prefix:" . implode( ':', $args );
3147         } else {
3148                 $key = $db . ':' . implode( ':', $args );
3149         }
3150         return $key;
3151 }
3152
3153 /**
3154  * Get an ASCII string identifying this wiki
3155  * This is used as a prefix in memcached keys
3156  *
3157  * @return String
3158  */
3159 function wfWikiID() {
3160         global $wgDBprefix, $wgDBname;
3161         if ( $wgDBprefix ) {
3162                 return "$wgDBname-$wgDBprefix";
3163         } else {
3164                 return $wgDBname;
3165         }
3166 }
3167
3168 /**
3169  * Split a wiki ID into DB name and table prefix
3170  *
3171  * @param $wiki String
3172  * @param $bits String
3173  */
3174 function wfSplitWikiID( $wiki ) {
3175         $bits = explode( '-', $wiki, 2 );
3176         if ( count( $bits ) < 2 ) {
3177                 $bits[] = '';
3178         }
3179         return $bits;
3180 }
3181
3182 /**
3183  * Get a Database object.
3184  *
3185  * @param $db Integer: index of the connection to get. May be DB_MASTER for the
3186  *            master (for write queries), DB_SLAVE for potentially lagged read
3187  *            queries, or an integer >= 0 for a particular server.
3188  *
3189  * @param $groups Mixed: query groups. An array of group names that this query
3190  *                belongs to. May contain a single string if the query is only
3191  *                in one group.
3192  *
3193  * @param $wiki String: the wiki ID, or false for the current wiki
3194  *
3195  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
3196  * will always return the same object, unless the underlying connection or load
3197  * balancer is manually destroyed.
3198  *
3199  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
3200  * updater to ensure that a proper database is being updated.
3201  *
3202  * @return DatabaseBase
3203  */
3204 function &wfGetDB( $db, $groups = array(), $wiki = false ) {
3205         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
3206 }
3207
3208 /**
3209  * Get a load balancer object.
3210  *
3211  * @param $wiki String: wiki ID, or false for the current wiki
3212  * @return LoadBalancer
3213  */
3214 function wfGetLB( $wiki = false ) {
3215         return wfGetLBFactory()->getMainLB( $wiki );
3216 }
3217
3218 /**
3219  * Get the load balancer factory object
3220  *
3221  * @return LBFactory
3222  */
3223 function &wfGetLBFactory() {
3224         return LBFactory::singleton();
3225 }
3226
3227 /**
3228  * Find a file.
3229  * Shortcut for RepoGroup::singleton()->findFile()
3230  *
3231  * @param $title String or Title object
3232  * @param $options Associative array of options:
3233  *     time:           requested time for an archived image, or false for the
3234  *                     current version. An image object will be returned which was
3235  *                     created at the specified time.
3236  *
3237  *     ignoreRedirect: If true, do not follow file redirects
3238  *
3239  *     private:        If true, return restricted (deleted) files if the current
3240  *                     user is allowed to view them. Otherwise, such files will not
3241  *                     be found.
3242  *
3243  *     bypassCache:    If true, do not use the process-local cache of File objects
3244  *
3245  * @return File, or false if the file does not exist
3246  */
3247 function wfFindFile( $title, $options = array() ) {
3248         return RepoGroup::singleton()->findFile( $title, $options );
3249 }
3250
3251 /**
3252  * Get an object referring to a locally registered file.
3253  * Returns a valid placeholder object if the file does not exist.
3254  *
3255  * @param $title Title or String
3256  * @return File, or null if passed an invalid Title
3257  */
3258 function wfLocalFile( $title ) {
3259         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
3260 }
3261
3262 /**
3263  * Stream a file to the browser. Back-compat alias for StreamFile::stream()
3264  * @deprecated since 1.19
3265  */
3266 function wfStreamFile( $fname, $headers = array() ) {
3267         StreamFile::stream( $fname, $headers );
3268 }
3269
3270 /**
3271  * Should low-performance queries be disabled?
3272  *
3273  * @return Boolean
3274  * @codeCoverageIgnore
3275  */
3276 function wfQueriesMustScale() {
3277         global $wgMiserMode;
3278         return $wgMiserMode
3279                 || ( SiteStats::pages() > 100000
3280                 && SiteStats::edits() > 1000000
3281                 && SiteStats::users() > 10000 );
3282 }
3283
3284 /**
3285  * Get the path to a specified script file, respecting file
3286  * extensions; this is a wrapper around $wgScriptExtension etc.
3287  *
3288  * @param $script String: script filename, sans extension
3289  * @return String
3290  */
3291 function wfScript( $script = 'index' ) {
3292         global $wgScriptPath, $wgScriptExtension;
3293         return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
3294 }
3295
3296 /**
3297  * Get the script URL.
3298  *
3299  * @return script URL
3300  */
3301 function wfGetScriptUrl() {
3302         if( isset( $_SERVER['SCRIPT_NAME'] ) ) {
3303                 #
3304                 # as it was called, minus the query string.
3305                 #
3306                 # Some sites use Apache rewrite rules to handle subdomains,
3307                 # and have PHP set up in a weird way that causes PHP_SELF
3308                 # to contain the rewritten URL instead of the one that the
3309                 # outside world sees.
3310                 #
3311                 # If in this mode, use SCRIPT_URL instead, which mod_rewrite
3312                 # provides containing the "before" URL.
3313                 return $_SERVER['SCRIPT_NAME'];
3314         } else {
3315                 return $_SERVER['URL'];
3316         }
3317 }
3318
3319 /**
3320  * Convenience function converts boolean values into "true"
3321  * or "false" (string) values
3322  *
3323  * @param $value Boolean
3324  * @return String
3325  */
3326 function wfBoolToStr( $value ) {
3327         return $value ? 'true' : 'false';
3328 }
3329
3330 /**
3331  * Load an extension messages file
3332  *
3333  * @deprecated since 1.16, warnings in 1.18, remove in 1.20
3334  * @codeCoverageIgnore
3335  */
3336 function wfLoadExtensionMessages() {
3337         wfDeprecated( __FUNCTION__ );
3338 }
3339
3340 /**
3341  * Get a platform-independent path to the null file, e.g. /dev/null
3342  *
3343  * @return string
3344  */
3345 function wfGetNull() {
3346         return wfIsWindows()
3347                 ? 'NUL'
3348                 : '/dev/null';
3349 }
3350
3351 /**
3352  * Throws a warning that $function is deprecated
3353  *
3354  * @param $function String
3355  * @return null
3356  */
3357 function wfDeprecated( $function ) {
3358         static $functionsWarned = array();
3359         if ( !isset( $functionsWarned[$function] ) ) {
3360                 $functionsWarned[$function] = true;
3361                 wfWarn( "Use of $function is deprecated.", 2 );
3362         }
3363 }
3364
3365 /**
3366  * Send a warning either to the debug log or in a PHP error depending on
3367  * $wgDevelopmentWarnings
3368  *
3369  * @param $msg String: message to send
3370  * @param $callerOffset Integer: number of items to go back in the backtrace to
3371  *        find the correct caller (1 = function calling wfWarn, ...)
3372  * @param $level Integer: PHP error level; only used when $wgDevelopmentWarnings
3373  *        is true
3374  */
3375 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
3376         global $wgDevelopmentWarnings;
3377
3378         $callers = wfDebugBacktrace();
3379         if ( isset( $callers[$callerOffset + 1] ) ) {
3380                 $callerfunc = $callers[$callerOffset + 1];
3381                 $callerfile = $callers[$callerOffset];
3382                 if ( isset( $callerfile['file'] ) && isset( $callerfile['line'] ) ) {
3383                         $file = $callerfile['file'] . ' at line ' . $callerfile['line'];
3384                 } else {
3385                         $file = '(internal function)';
3386                 }
3387                 $func = '';
3388                 if ( isset( $callerfunc['class'] ) ) {
3389                         $func .= $callerfunc['class'] . '::';
3390                 }
3391                 if ( isset( $callerfunc['function'] ) ) {
3392                         $func .= $callerfunc['function'];
3393                 }
3394                 $msg .= " [Called from $func in $file]";
3395         }
3396
3397         if ( $wgDevelopmentWarnings ) {
3398                 trigger_error( $msg, $level );
3399         } else {
3400                 wfDebug( "$msg\n" );
3401         }
3402 }
3403
3404 /**
3405  * Modern version of wfWaitForSlaves(). Instead of looking at replication lag
3406  * and waiting for it to go down, this waits for the slaves to catch up to the
3407  * master position. Use this when updating very large numbers of rows, as
3408  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
3409  * a no-op if there are no slaves.
3410  *
3411  * @param $maxLag Integer (deprecated)
3412  * @param $wiki mixed Wiki identifier accepted by wfGetLB
3413  * @return null
3414  */
3415 function wfWaitForSlaves( $maxLag = false, $wiki = false ) {
3416         $lb = wfGetLB( $wiki );
3417         // bug 27975 - Don't try to wait for slaves if there are none
3418         // Prevents permission error when getting master position
3419         if ( $lb->getServerCount() > 1 ) {
3420                 $dbw = $lb->getConnection( DB_MASTER );
3421                 $pos = $dbw->getMasterPos();
3422                 $lb->waitForAll( $pos );
3423         }
3424 }
3425
3426 /**
3427  * Used to be used for outputting text in the installer/updater
3428  * @deprecated since 1.18, warnings in 1.18, remove in 1.20
3429  */
3430 function wfOut( $s ) {
3431         wfDeprecated( __METHOD__ );
3432         global $wgCommandLineMode;
3433         if ( $wgCommandLineMode ) {
3434                 echo $s;
3435         } else {
3436                 echo htmlspecialchars( $s );
3437         }
3438         flush();
3439 }
3440
3441 /**
3442  * Count down from $n to zero on the terminal, with a one-second pause
3443  * between showing each number. For use in command-line scripts.
3444  * @codeCoverageIgnore
3445  */
3446 function wfCountDown( $n ) {
3447         for ( $i = $n; $i >= 0; $i-- ) {
3448                 if ( $i != $n ) {
3449                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3450                 }
3451                 echo $i;
3452                 flush();
3453                 if ( $i ) {
3454                         sleep( 1 );
3455                 }
3456         }
3457         echo "\n";
3458 }
3459
3460 /**
3461  * Generate a random 32-character hexadecimal token.
3462  * @param $salt Mixed: some sort of salt, if necessary, to add to random
3463  *              characters before hashing.
3464  * @return string
3465  * @codeCoverageIgnore
3466  */
3467 function wfGenerateToken( $salt = '' ) {
3468         $salt = serialize( $salt );
3469         return md5( mt_rand( 0, 0x7fffffff ) . $salt );
3470 }
3471
3472 /**
3473  * Replace all invalid characters with -
3474  *
3475  * @param $name Mixed: filename to process
3476  * @return String
3477  */
3478 function wfStripIllegalFilenameChars( $name ) {
3479         global $wgIllegalFileChars;
3480         $name = wfBaseName( $name );
3481         $name = preg_replace(
3482                 "/[^" . Title::legalChars() . "]" .
3483                         ( $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '' ) .
3484                         "/",
3485                 '-',
3486                 $name
3487         );
3488         return $name;
3489 }
3490
3491 /**
3492  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit;
3493  *
3494  * @return Integer value memory was set to.
3495  */
3496 function wfMemoryLimit() {
3497         global $wgMemoryLimit;
3498         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3499         if( $memlimit != -1 ) {
3500                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3501                 if( $conflimit == -1 ) {
3502                         wfDebug( "Removing PHP's memory limit\n" );
3503                         wfSuppressWarnings();
3504                         ini_set( 'memory_limit', $conflimit );
3505                         wfRestoreWarnings();
3506                         return $conflimit;
3507                 } elseif ( $conflimit > $memlimit ) {
3508                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3509                         wfSuppressWarnings();
3510                         ini_set( 'memory_limit', $conflimit );
3511                         wfRestoreWarnings();
3512                         return $conflimit;
3513                 }
3514         }
3515         return $memlimit;
3516 }
3517
3518 /**
3519  * Converts shorthand byte notation to integer form
3520  *
3521  * @param $string String
3522  * @return Integer
3523  */
3524 function wfShorthandToInteger( $string = '' ) {
3525         $string = trim( $string );
3526         if( $string === '' ) {
3527                 return -1;
3528         }
3529         $last = $string[strlen( $string ) - 1];
3530         $val = intval( $string );
3531         switch( $last ) {
3532                 case 'g':
3533                 case 'G':
3534                         $val *= 1024;
3535                         // break intentionally missing
3536                 case 'm':
3537                 case 'M':
3538                         $val *= 1024;
3539                         // break intentionally missing
3540                 case 'k':
3541                 case 'K':
3542                         $val *= 1024;
3543         }
3544
3545         return $val;
3546 }
3547
3548 /**
3549  * Get the normalised IETF language tag
3550  * See unit test for examples.
3551  *
3552  * @param $code String: The language code.
3553  * @return $langCode String: The language code which complying with BCP 47 standards.
3554  */
3555 function wfBCP47( $code ) {
3556         $codeSegment = explode( '-', $code );
3557         $codeBCP = array();
3558         foreach ( $codeSegment as $segNo => $seg ) {
3559                 if ( count( $codeSegment ) > 0 ) {
3560                         // when previous segment is x, it is a private segment and should be lc
3561                         if( $segNo > 0 && strtolower( $codeSegment[($segNo - 1)] ) == 'x') {
3562                                 $codeBCP[$segNo] = strtolower( $seg );
3563                         // ISO 3166 country code
3564                         } elseif ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3565                                 $codeBCP[$segNo] = strtoupper( $seg );
3566                         // ISO 15924 script code
3567                         } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3568                                 $codeBCP[$segNo] = ucfirst( strtolower( $seg ) );
3569                         // Use lowercase for other cases
3570                         } else {
3571                                 $codeBCP[$segNo] = strtolower( $seg );
3572                         }
3573                 } else {
3574                 // Use lowercase for single segment
3575                         $codeBCP[$segNo] = strtolower( $seg );
3576                 }
3577         }
3578         $langCode = implode( '-', $codeBCP );
3579         return $langCode;
3580 }
3581
3582 /**
3583  * Get a cache object.
3584  *
3585  * @param $inputType integer Cache type, one the the CACHE_* constants.
3586  * @return BagOStuff
3587  */
3588 function wfGetCache( $inputType ) {
3589         return ObjectCache::getInstance( $inputType );
3590 }
3591
3592 /**
3593  * Get the main cache object
3594  *
3595  * @return BagOStuff
3596  */
3597 function wfGetMainCache() {
3598         global $wgMainCacheType;
3599         return ObjectCache::getInstance( $wgMainCacheType );
3600 }
3601
3602 /**
3603  * Get the cache object used by the message cache
3604  *
3605  * @return BagOStuff
3606  */
3607 function wfGetMessageCacheStorage() {
3608         global $wgMessageCacheType;
3609         return ObjectCache::getInstance( $wgMessageCacheType );
3610 }
3611
3612 /**
3613  * Get the cache object used by the parser cache
3614  *
3615  * @return BagOStuff
3616  */
3617 function wfGetParserCacheStorage() {
3618         global $wgParserCacheType;
3619         return ObjectCache::getInstance( $wgParserCacheType );
3620 }
3621
3622 /**
3623  * Call hook functions defined in $wgHooks
3624  *
3625  * @param $event String: event name
3626  * @param $args Array: parameters passed to hook functions
3627  * @return Boolean
3628  */
3629 function wfRunHooks( $event, $args = array() ) {
3630         return Hooks::run( $event, $args );
3631 }