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