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         $mem = sprintf( "%5.1fM", ( memory_get_usage( true ) / (1024*1024) ) );
 760         return "$prefix $mem  " ;
 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 ) > 65506 ) {
 856                                 $text = substr( $text, 0, 65506 );
 857                         }
 858
 859                         if ( substr( $text, -1 ) != "\n" ) {
 860                                 $text .= "\n";
 861                         }
 862                 } elseif ( strlen( $text ) > 65507 ) {
 863                         $text = substr( $text, 0, 65507 );
 864                 }
 865
 866                 $sock = socket_create( $domain, SOCK_DGRAM, SOL_UDP );
 867                 if ( !$sock ) {
 868                         return;
 869                 }
 870
 871                 socket_sendto( $sock, $text, strlen( $text ), 0, $host, $port );
 872                 socket_close( $sock );
 873         } else {
 874                 wfSuppressWarnings();
 875                 $exists = file_exists( $file );
 876                 $size = $exists ? filesize( $file ) : false;
 877                 if ( !$exists || ( $size !== false && $size + strlen( $text ) < 0x7fffffff ) ) {
 878                         file_put_contents( $file, $text, FILE_APPEND );
 879                 }
 880                 wfRestoreWarnings();
 881         }
 882 }
 883
 884 /**
 885  * @todo document
 886  */
 887 function wfLogProfilingData() {
 888         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
 889         global $wgProfileLimit, $wgUser;
 890
 891         $profiler = Profiler::instance();
 892
 893         # Profiling must actually be enabled...
 894         if ( $profiler->isStub() ) {
 895                 return;
 896         }
 897
 898         // Get total page request time and only show pages that longer than
 899         // $wgProfileLimit time (default is 0)
 900         $now = wfTime();
 901         $elapsed = $now - $wgRequestTime;
 902         if ( $elapsed <= $wgProfileLimit ) {
 903                 return;
 904         }
 905
 906         $profiler->logData();
 907
 908         // Check whether this should be logged in the debug file.
 909         if ( $wgDebugLogFile == '' || ( !$wgDebugRawPage && wfIsDebugRawPage() ) ) {
 910                 return;
 911         }
 912
 913         $forward = '';
 914         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
 915                 $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
 916         }
 917         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
 918                 $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
 919         }
 920         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
 921                 $forward .= ' from ' . $_SERVER['HTTP_FROM'];
 922         }
 923         if ( $forward ) {
 924                 $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
 925         }
 926         // Don't load $wgUser at this late stage just for statistics purposes
 927         // @todo FIXME: We can detect some anons even if it is not loaded. See User::getId()
 928         if ( $wgUser->isItemLoaded( 'id' ) && $wgUser->isAnon() ) {
 929                 $forward .= ' anon';
 930         }
 931         $log = sprintf( "%s\t%04.3f\t%s\n",
 932                 gmdate( 'YmdHis' ), $elapsed,
 933                 urldecode( $wgRequest->getRequestURL() . $forward ) );
 934
 935         wfErrorLog( $log . $profiler->getOutput(), $wgDebugLogFile );
 936 }
 937
 938 /**
 939  * Check if the wiki read-only lock file is present. This can be used to lock
 940  * off editing functions, but doesn't guarantee that the database will not be
 941  * modified.
 942  *
 943  * @return bool
 944  */
 945 function wfReadOnly() {
 946         global $wgReadOnlyFile, $wgReadOnly;
 947
 948         if ( !is_null( $wgReadOnly ) ) {
 949                 return (bool)$wgReadOnly;
 950         }
 951         if ( $wgReadOnlyFile == '' ) {
 952                 return false;
 953         }
 954         // Set $wgReadOnly for faster access next time
 955         if ( is_file( $wgReadOnlyFile ) ) {
 956                 $wgReadOnly = file_get_contents( $wgReadOnlyFile );
 957         } else {
 958                 $wgReadOnly = false;
 959         }
 960         return (bool)$wgReadOnly;
 961 }
 962
 963 function wfReadOnlyReason() {
 964         global $wgReadOnly;
 965         wfReadOnly();
 966         return $wgReadOnly;
 967 }
 968
 969 /**
 970  * Return a Language object from $langcode
 971  *
 972  * @param $langcode Mixed: either:
 973  *                  - a Language object
 974  *                  - code of the language to get the message for, if it is
 975  *                    a valid code create a language for that language, if
 976  *                    it is a string but not a valid code then make a basic
 977  *                    language object
 978  *                  - a boolean: if it's false then use the global object for
 979  *                    the current user's language (as a fallback for the old parameter
 980  *                    functionality), or if it is true then use global object
 981  *                    for the wiki's content language.
 982  * @return Language object
 983  */
 984 function wfGetLangObj( $langcode = false ) {
 985         # Identify which language to get or create a language object for.
 986         # Using is_object here due to Stub objects.
 987         if( is_object( $langcode ) ) {
 988                 # Great, we already have the object (hopefully)!
 989                 return $langcode;
 990         }
 991
 992         global $wgContLang, $wgLanguageCode;
 993         if( $langcode === true || $langcode === $wgLanguageCode ) {
 994                 # $langcode is the language code of the wikis content language object.
 995                 # or it is a boolean and value is true
 996                 return $wgContLang;
 997         }
 998
 999         global $wgLang;
1000         if( $langcode === false || $langcode === $wgLang->getCode() ) {
1001                 # $langcode is the language code of user language object.
1002                 # or it was a boolean and value is false
1003                 return $wgLang;
1004         }
1005
1006         $validCodes = array_keys( Language::getLanguageNames() );
1007         if( in_array( $langcode, $validCodes ) ) {
1008                 # $langcode corresponds to a valid language.
1009                 return Language::factory( $langcode );
1010         }
1011
1012         # $langcode is a string, but not a valid language code; use content language.
1013         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
1014         return $wgContLang;
1015 }
1016
1017 /**
1018  * Old function when $wgBetterDirectionality existed
1019  * Removed in core, kept in extensions for backwards compat.
1020  *
1021  * @deprecated since 1.18
1022  * @return Language
1023  */
1024 function wfUILang() {
1025         global $wgLang;
1026         return $wgLang;
1027 }
1028
1029 /**
1030  * This is the new function for getting translated interface messages.
1031  * See the Message class for documentation how to use them.
1032  * The intention is that this function replaces all old wfMsg* functions.
1033  * @param $key \string Message key.
1034  * Varargs: normal message parameters.
1035  * @return Message
1036  * @since 1.17
1037  */
1038 function wfMessage( $key /*...*/) {
1039         $params = func_get_args();
1040         array_shift( $params );
1041         if ( isset( $params[0] ) && is_array( $params[0] ) ) {
1042                 $params = $params[0];
1043         }
1044         return new Message( $key, $params );
1045 }
1046
1047 /**
1048  * This function accepts multiple message keys and returns a message instance
1049  * for the first message which is non-empty. If all messages are empty then an
1050  * instance of the first message key is returned.
1051  * @param varargs: message keys
1052  * @return Message
1053  * @since 1.18
1054  */
1055 function wfMessageFallback( /*...*/ ) {
1056         $args = func_get_args();
1057         return MWFunction::callArray( 'Message::newFallbackSequence', $args );
1058 }
1059
1060 /**
1061  * Get a message from anywhere, for the current user language.
1062  *
1063  * Use wfMsgForContent() instead if the message should NOT
1064  * change depending on the user preferences.
1065  *
1066  * @param $key String: lookup key for the message, usually
1067  *    defined in languages/Language.php
1068  *
1069  * Parameters to the message, which can be used to insert variable text into
1070  * it, can be passed to this function in the following formats:
1071  * - One per argument, starting at the second parameter
1072  * - As an array in the second parameter
1073  * These are not shown in the function definition.
1074  *
1075  * @return String
1076  */
1077 function wfMsg( $key ) {
1078         $args = func_get_args();
1079         array_shift( $args );
1080         return wfMsgReal( $key, $args );
1081 }
1082
1083 /**
1084  * Same as above except doesn't transform the message
1085  *
1086  * @param $key String
1087  * @return String
1088  */
1089 function wfMsgNoTrans( $key ) {
1090         $args = func_get_args();
1091         array_shift( $args );
1092         return wfMsgReal( $key, $args, true, false, false );
1093 }
1094
1095 /**
1096  * Get a message from anywhere, for the current global language
1097  * set with $wgLanguageCode.
1098  *
1099  * Use this if the message should NOT change dependent on the
1100  * language set in the user's preferences. This is the case for
1101  * most text written into logs, as well as link targets (such as
1102  * the name of the copyright policy page). Link titles, on the
1103  * other hand, should be shown in the UI language.
1104  *
1105  * Note that MediaWiki allows users to change the user interface
1106  * language in their preferences, but a single installation
1107  * typically only contains content in one language.
1108  *
1109  * Be wary of this distinction: If you use wfMsg() where you should
1110  * use wfMsgForContent(), a user of the software may have to
1111  * customize potentially hundreds of messages in
1112  * order to, e.g., fix a link in every possible language.
1113  *
1114  * @param $key String: lookup key for the message, usually
1115  *     defined in languages/Language.php
1116  * @return String
1117  */
1118 function wfMsgForContent( $key ) {
1119         global $wgForceUIMsgAsContentMsg;
1120         $args = func_get_args();
1121         array_shift( $args );
1122         $forcontent = true;
1123         if( is_array( $wgForceUIMsgAsContentMsg ) &&
1124                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
1125         {
1126                 $forcontent = false;
1127         }
1128         return wfMsgReal( $key, $args, true, $forcontent );
1129 }
1130
1131 /**
1132  * Same as above except doesn't transform the message
1133  *
1134  * @param $key String
1135  * @return String
1136  */
1137 function wfMsgForContentNoTrans( $key ) {
1138         global $wgForceUIMsgAsContentMsg;
1139         $args = func_get_args();
1140         array_shift( $args );
1141         $forcontent = true;
1142         if( is_array( $wgForceUIMsgAsContentMsg ) &&
1143                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
1144         {
1145                 $forcontent = false;
1146         }
1147         return wfMsgReal( $key, $args, true, $forcontent, false );
1148 }
1149
1150 /**
1151  * Really get a message
1152  *
1153  * @param $key String: key to get.
1154  * @param $args
1155  * @param $useDB Boolean
1156  * @param $forContent Mixed: Language code, or false for user lang, true for content lang.
1157  * @param $transform Boolean: Whether or not to transform the message.
1158  * @return String: the requested message.
1159  */
1160 function wfMsgReal( $key, $args, $useDB = true, $forContent = false, $transform = true ) {
1161         wfProfileIn( __METHOD__ );
1162         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
1163         $message = wfMsgReplaceArgs( $message, $args );
1164         wfProfileOut( __METHOD__ );
1165         return $message;
1166 }
1167
1168 /**
1169  * Fetch a message string value, but don't replace any keys yet.
1170  *
1171  * @param $key String
1172  * @param $useDB Bool
1173  * @param $langCode String: Code of the language to get the message for, or
1174  *                  behaves as a content language switch if it is a boolean.
1175  * @param $transform Boolean: whether to parse magic words, etc.
1176  * @return string
1177  */
1178 function wfMsgGetKey( $key, $useDB = true, $langCode = false, $transform = true ) {
1179         wfRunHooks( 'NormalizeMessageKey', array( &$key, &$useDB, &$langCode, &$transform ) );
1180
1181         $cache = MessageCache::singleton();
1182         $message = $cache->get( $key, $useDB, $langCode );
1183         if( $message === false ) {
1184                 $message = '&lt;' . htmlspecialchars( $key ) . '&gt;';
1185         } elseif ( $transform ) {
1186                 $message = $cache->transform( $message );
1187         }
1188         return $message;
1189 }
1190
1191 /**
1192  * Replace message parameter keys on the given formatted output.
1193  *
1194  * @param $message String
1195  * @param $args Array
1196  * @return string
1197  * @private
1198  */
1199 function wfMsgReplaceArgs( $message, $args ) {
1200         # Fix windows line-endings
1201         # Some messages are split with explode("\n", $msg)
1202         $message = str_replace( "\r", '', $message );
1203
1204         // Replace arguments
1205         if ( count( $args ) ) {
1206                 if ( is_array( $args[0] ) ) {
1207                         $args = array_values( $args[0] );
1208                 }
1209                 $replacementKeys = array();
1210                 foreach( $args as $n => $param ) {
1211                         $replacementKeys['$' . ( $n + 1 )] = $param;
1212                 }
1213                 $message = strtr( $message, $replacementKeys );
1214         }
1215
1216         return $message;
1217 }
1218
1219 /**
1220  * Return an HTML-escaped version of a message.
1221  * Parameter replacements, if any, are done *after* the HTML-escaping,
1222  * so parameters may contain HTML (eg links or form controls). Be sure
1223  * to pre-escape them if you really do want plaintext, or just wrap
1224  * the whole thing in htmlspecialchars().
1225  *
1226  * @param $key String
1227  * @param string ... parameters
1228  * @return string
1229  */
1230 function wfMsgHtml( $key ) {
1231         $args = func_get_args();
1232         array_shift( $args );
1233         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key ) ), $args );
1234 }
1235
1236 /**
1237  * Return an HTML version of message
1238  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
1239  * so parameters may contain HTML (eg links or form controls). Be sure
1240  * to pre-escape them if you really do want plaintext, or just wrap
1241  * the whole thing in htmlspecialchars().
1242  *
1243  * @param $key String
1244  * @param string ... parameters
1245  * @return string
1246  */
1247 function wfMsgWikiHtml( $key ) {
1248         $args = func_get_args();
1249         array_shift( $args );
1250         return wfMsgReplaceArgs(
1251                 MessageCache::singleton()->parse( wfMsgGetKey( $key ), null,
1252                 /* can't be set to false */ true, /* interface */ true )->getText(),
1253                 $args );
1254 }
1255
1256 /**
1257  * Returns message in the requested format
1258  * @param $key String: key of the message
1259  * @param $options Array: processing rules. Can take the following options:
1260  *   <i>parse</i>: parses wikitext to HTML
1261  *   <i>parseinline</i>: parses wikitext to HTML and removes the surrounding
1262  *       p's added by parser or tidy
1263  *   <i>escape</i>: filters message through htmlspecialchars
1264  *   <i>escapenoentities</i>: same, but allows entity references like &#160; through
1265  *   <i>replaceafter</i>: parameters are substituted after parsing or escaping
1266  *   <i>parsemag</i>: transform the message using magic phrases
1267  *   <i>content</i>: fetch message for content language instead of interface
1268  * Also can accept a single associative argument, of the form 'language' => 'xx':
1269  *   <i>language</i>: Language object or language code to fetch message for
1270  *       (overriden by <i>content</i>).
1271  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
1272  *
1273  * @return String
1274  */
1275 function wfMsgExt( $key, $options ) {
1276         $args = func_get_args();
1277         array_shift( $args );
1278         array_shift( $args );
1279         $options = (array)$options;
1280
1281         foreach( $options as $arrayKey => $option ) {
1282                 if( !preg_match( '/^[0-9]+|language$/', $arrayKey ) ) {
1283                         # An unknown index, neither numeric nor "language"
1284                         wfWarn( "wfMsgExt called with incorrect parameter key $arrayKey", 1, E_USER_WARNING );
1285                 } elseif( preg_match( '/^[0-9]+$/', $arrayKey ) && !in_array( $option,
1286                 array( 'parse', 'parseinline', 'escape', 'escapenoentities',
1287                 'replaceafter', 'parsemag', 'content' ) ) ) {
1288                         # A numeric index with unknown value
1289                         wfWarn( "wfMsgExt called with incorrect parameter $option", 1, E_USER_WARNING );
1290                 }
1291         }
1292
1293         if( in_array( 'content', $options, true ) ) {
1294                 $forContent = true;
1295                 $langCode = true;
1296                 $langCodeObj = null;
1297         } elseif( array_key_exists( 'language', $options ) ) {
1298                 $forContent = false;
1299                 $langCode = wfGetLangObj( $options['language'] );
1300                 $langCodeObj = $langCode;
1301         } else {
1302                 $forContent = false;
1303                 $langCode = false;
1304                 $langCodeObj = null;
1305         }
1306
1307         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
1308
1309         if( !in_array( 'replaceafter', $options, true ) ) {
1310                 $string = wfMsgReplaceArgs( $string, $args );
1311         }
1312
1313         $messageCache = MessageCache::singleton();
1314         if( in_array( 'parse', $options, true ) ) {
1315                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj )->getText();
1316         } elseif ( in_array( 'parseinline', $options, true ) ) {
1317                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj )->getText();
1318                 $m = array();
1319                 if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
1320                         $string = $m[1];
1321                 }
1322         } elseif ( in_array( 'parsemag', $options, true ) ) {
1323                 $string = $messageCache->transform( $string,
1324                                 !$forContent, $langCodeObj );
1325         }
1326
1327         if ( in_array( 'escape', $options, true ) ) {
1328                 $string = htmlspecialchars ( $string );
1329         } elseif ( in_array( 'escapenoentities', $options, true ) ) {
1330                 $string = Sanitizer::escapeHtmlAllowEntities( $string );
1331         }
1332
1333         if( in_array( 'replaceafter', $options, true ) ) {
1334                 $string = wfMsgReplaceArgs( $string, $args );
1335         }
1336
1337         return $string;
1338 }
1339
1340 /**
1341  * Since wfMsg() and co suck, they don't return false if the message key they
1342  * looked up didn't exist but a XHTML string, this function checks for the
1343  * nonexistance of messages by checking the MessageCache::get() result directly.
1344  *
1345  * @param $key      String: the message key looked up
1346  * @return Boolean True if the message *doesn't* exist.
1347  */
1348 function wfEmptyMsg( $key ) {
1349         return MessageCache::singleton()->get( $key, /*useDB*/true, /*content*/false ) === false;
1350 }
1351
1352 /**
1353  * Throw a debugging exception. This function previously once exited the process,
1354  * but now throws an exception instead, with similar results.
1355  *
1356  * @param $msg String: message shown when dieing.
1357  */
1358 function wfDebugDieBacktrace( $msg = '' ) {
1359         throw new MWException( $msg );
1360 }
1361
1362 /**
1363  * Fetch server name for use in error reporting etc.
1364  * Use real server name if available, so we know which machine
1365  * in a server farm generated the current page.
1366  *
1367  * @return string
1368  */
1369 function wfHostname() {
1370         static $host;
1371         if ( is_null( $host ) ) {
1372                 if ( function_exists( 'posix_uname' ) ) {
1373                         // This function not present on Windows
1374                         $uname = posix_uname();
1375                 } else {
1376                         $uname = false;
1377                 }
1378                 if( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1379                         $host = $uname['nodename'];
1380                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1381                         # Windows computer name
1382                         $host = getenv( 'COMPUTERNAME' );
1383                 } else {
1384                         # This may be a virtual server.
1385                         $host = $_SERVER['SERVER_NAME'];
1386                 }
1387         }
1388         return $host;
1389 }
1390
1391 /**
1392  * Returns a HTML comment with the elapsed time since request.
1393  * This method has no side effects.
1394  *
1395  * @return string
1396  */
1397 function wfReportTime() {
1398         global $wgRequestTime, $wgShowHostnames;
1399
1400         $now = wfTime();
1401         $elapsed = $now - $wgRequestTime;
1402
1403         return $wgShowHostnames
1404                 ? sprintf( '<!-- Served by %s in %01.3f secs. -->', wfHostname(), $elapsed )
1405                 : sprintf( '<!-- Served in %01.3f secs. -->', $elapsed );
1406 }
1407
1408 /**
1409  * Safety wrapper for debug_backtrace().
1410  *
1411  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
1412  * murky circumstances, which may be triggered in part by stub objects
1413  * or other fancy talkin'.
1414  *
1415  * Will return an empty array if Zend Optimizer is detected or if
1416  * debug_backtrace is disabled, otherwise the output from
1417  * debug_backtrace() (trimmed).
1418  *
1419  * @param $limit int This parameter can be used to limit the number of stack frames returned
1420  *
1421  * @return array of backtrace information
1422  */
1423 function wfDebugBacktrace( $limit = 0 ) {
1424         static $disabled = null;
1425
1426         if( extension_loaded( 'Zend Optimizer' ) ) {
1427                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
1428                 return array();
1429         }
1430
1431         if ( is_null( $disabled ) ) {
1432                 $disabled = false;
1433                 $functions = explode( ',', ini_get( 'disable_functions' ) );
1434                 $functions = array_map( 'trim', $functions );
1435                 $functions = array_map( 'strtolower', $functions );
1436                 if ( in_array( 'debug_backtrace', $functions ) ) {
1437                         wfDebug( "debug_backtrace is in disabled_functions\n" );
1438                         $disabled = true;
1439                 }
1440         }
1441         if ( $disabled ) {
1442                 return array();
1443         }
1444
1445         if ( $limit && version_compare( PHP_VERSION, '5.4.0', '>=' ) ) {
1446                 return array_slice( debug_backtrace( DEBUG_BACKTRACE_PROVIDE_OBJECT, $limit ), 1 );
1447         } else {
1448                 return array_slice( debug_backtrace(), 1 );
1449         }
1450 }
1451
1452 /**
1453  * Get a debug backtrace as a string
1454  *
1455  * @return string
1456  */
1457 function wfBacktrace() {
1458         global $wgCommandLineMode;
1459
1460         if ( $wgCommandLineMode ) {
1461                 $msg = '';
1462         } else {
1463                 $msg = "<ul>\n";
1464         }
1465         $backtrace = wfDebugBacktrace();
1466         foreach( $backtrace as $call ) {
1467                 if( isset( $call['file'] ) ) {
1468                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
1469                         $file = $f[count( $f ) - 1];
1470                 } else {
1471                         $file = '-';
1472                 }
1473                 if( isset( $call['line'] ) ) {
1474                         $line = $call['line'];
1475                 } else {
1476                         $line = '-';
1477                 }
1478                 if ( $wgCommandLineMode ) {
1479                         $msg .= "$file line $line calls ";
1480                 } else {
1481                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
1482                 }
1483                 if( !empty( $call['class'] ) ) {
1484                         $msg .= $call['class'] . $call['type'];
1485                 }
1486                 $msg .= $call['function'] . '()';
1487
1488                 if ( $wgCommandLineMode ) {
1489                         $msg .= "\n";
1490                 } else {
1491                         $msg .= "</li>\n";
1492                 }
1493         }
1494         if ( $wgCommandLineMode ) {
1495                 $msg .= "\n";
1496         } else {
1497                 $msg .= "</ul>\n";
1498         }
1499
1500         return $msg;
1501 }
1502
1503 /**
1504  * Get the name of the function which called this function
1505  *
1506  * @param $level Int
1507  * @return Bool|string
1508  */
1509 function wfGetCaller( $level = 2 ) {
1510         $backtrace = wfDebugBacktrace( $level );
1511         if ( isset( $backtrace[$level] ) ) {
1512                 return wfFormatStackFrame( $backtrace[$level] );
1513         } else {
1514                 $caller = 'unknown';
1515         }
1516         return $caller;
1517 }
1518
1519 /**
1520  * Return a string consisting of callers in the stack. Useful sometimes
1521  * for profiling specific points.
1522  *
1523  * @param $limit The maximum depth of the stack frame to return, or false for
1524  *               the entire stack.
1525  * @return String
1526  */
1527 function wfGetAllCallers( $limit = 3 ) {
1528         $trace = array_reverse( wfDebugBacktrace() );
1529         if ( !$limit || $limit > count( $trace ) - 1 ) {
1530                 $limit = count( $trace ) - 1;
1531         }
1532         $trace = array_slice( $trace, -$limit - 1, $limit );
1533         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1534 }
1535
1536 /**
1537  * Return a string representation of frame
1538  *
1539  * @param $frame Array
1540  * @return Bool
1541  */
1542 function wfFormatStackFrame( $frame ) {
1543         return isset( $frame['class'] ) ?
1544                 $frame['class'] . '::' . $frame['function'] :
1545                 $frame['function'];
1546 }
1547
1548
1549 /* Some generic result counters, pulled out of SearchEngine */
1550
1551
1552 /**
1553  * @todo document
1554  *
1555  * @param $offset Int
1556  * @param $limit Int
1557  * @return String
1558  */
1559 function wfShowingResults( $offset, $limit ) {
1560         global $wgLang;
1561         return wfMsgExt(
1562                 'showingresults',
1563                 array( 'parseinline' ),
1564                 $wgLang->formatNum( $limit ),
1565                 $wgLang->formatNum( $offset + 1 )
1566         );
1567 }
1568
1569 /**
1570  * Generate (prev x| next x) (20|50|100...) type links for paging
1571  *
1572  * @param $offset String
1573  * @param $limit Integer
1574  * @param $link String
1575  * @param $query String: optional URL query parameter string
1576  * @param $atend Bool: optional param for specified if this is the last page
1577  * @return String
1578  */
1579 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
1580         global $wgLang;
1581         $fmtLimit = $wgLang->formatNum( $limit );
1582         // @todo FIXME: Why on earth this needs one message for the text and another one for tooltip?
1583         # Get prev/next link display text
1584         $prev = wfMsgExt( 'prevn', array( 'parsemag', 'escape' ), $fmtLimit );
1585         $next = wfMsgExt( 'nextn', array( 'parsemag', 'escape' ), $fmtLimit );
1586         # Get prev/next link title text
1587         $pTitle = wfMsgExt( 'prevn-title', array( 'parsemag', 'escape' ), $fmtLimit );
1588         $nTitle = wfMsgExt( 'nextn-title', array( 'parsemag', 'escape' ), $fmtLimit );
1589         # Fetch the title object
1590         if( is_object( $link ) ) {
1591                 $title =& $link;
1592         } else {
1593                 $title = Title::newFromText( $link );
1594                 if( is_null( $title ) ) {
1595                         return false;
1596                 }
1597         }
1598         # Make 'previous' link
1599         if( 0 != $offset ) {
1600                 $po = $offset - $limit;
1601                 $po = max( $po, 0 );
1602                 $q = "limit={$limit}&offset={$po}";
1603                 if( $query != '' ) {
1604                         $q .= '&' . $query;
1605                 }
1606                 $plink = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$pTitle}\" class=\"mw-prevlink\">{$prev}</a>";
1607         } else {
1608                 $plink = $prev;
1609         }
1610         # Make 'next' link
1611         $no = $offset + $limit;
1612         $q = "limit={$limit}&offset={$no}";
1613         if( $query != '' ) {
1614                 $q .= '&' . $query;
1615         }
1616         if( $atend ) {
1617                 $nlink = $next;
1618         } else {
1619                 $nlink = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$nTitle}\" class=\"mw-nextlink\">{$next}</a>";
1620         }
1621         # Make links to set number of items per page
1622         $nums = $wgLang->pipeList( array(
1623                 wfNumLink( $offset, 20, $title, $query ),
1624                 wfNumLink( $offset, 50, $title, $query ),
1625                 wfNumLink( $offset, 100, $title, $query ),
1626                 wfNumLink( $offset, 250, $title, $query ),
1627                 wfNumLink( $offset, 500, $title, $query )
1628         ) );
1629         return wfMsgHtml( 'viewprevnext', $plink, $nlink, $nums );
1630 }
1631
1632 /**
1633  * Generate links for (20|50|100...) items-per-page links
1634  *
1635  * @param $offset String
1636  * @param $limit Integer
1637  * @param $title Title
1638  * @param $query String: optional URL query parameter string
1639  */
1640 function wfNumLink( $offset, $limit, $title, $query = '' ) {
1641         global $wgLang;
1642         if( $query == '' ) {
1643                 $q = '';
1644         } else {
1645                 $q = $query.'&';
1646         }
1647         $q .= "limit={$limit}&offset={$offset}";
1648         $fmtLimit = $wgLang->formatNum( $limit );
1649         $lTitle = wfMsgExt( 'shown-title', array( 'parsemag', 'escape' ), $limit );
1650         $s = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$lTitle}\" class=\"mw-numlink\">{$fmtLimit}</a>";
1651         return $s;
1652 }
1653
1654 /**
1655  * @todo document
1656  * @todo FIXME: We may want to blacklist some broken browsers
1657  *
1658  * @param $force Bool
1659  * @return bool Whereas client accept gzip compression
1660  */
1661 function wfClientAcceptsGzip( $force = false ) {
1662         static $result = null;
1663         if ( $result === null || $force ) {
1664                 $result = false;
1665                 if( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1666                         # @todo FIXME: We may want to blacklist some broken browsers
1667                         $m = array();
1668                         if( preg_match(
1669                                 '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1670                                 $_SERVER['HTTP_ACCEPT_ENCODING'],
1671                                 $m )
1672                         )
1673                         {
1674                                 if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1675                                         $result = false;
1676                                         return $result;
1677                                 }
1678                                 wfDebug( " accepts gzip\n" );
1679                                 $result = true;
1680                         }
1681                 }
1682         }
1683         return $result;
1684 }
1685
1686 /**
1687  * Obtain the offset and limit values from the request string;
1688  * used in special pages
1689  *
1690  * @param $deflimit Int default limit if none supplied
1691  * @param $optionname String Name of a user preference to check against
1692  * @return array
1693  *
1694  */
1695 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
1696         global $wgRequest;
1697         return $wgRequest->getLimitOffset( $deflimit, $optionname );
1698 }
1699
1700 /**
1701  * Escapes the given text so that it may be output using addWikiText()
1702  * without any linking, formatting, etc. making its way through. This
1703  * is achieved by substituting certain characters with HTML entities.
1704  * As required by the callers, <nowiki> is not used.
1705  *
1706  * @param $text String: text to be escaped
1707  * @return String
1708  */
1709 function wfEscapeWikiText( $text ) {
1710         $text = strtr( "\n$text", array(
1711                 '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
1712                 '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
1713                 '{' => '&#123;', '|' => '&#124;', '}' => '&#125;',
1714                 "\n#" => "\n&#35;", "\n*" => "\n&#42;",
1715                 "\n:" => "\n&#58;", "\n;" => "\n&#59;",
1716                 '://' => '&#58;//', 'ISBN ' => 'ISBN&#32;', 'RFC ' => 'RFC&#32;',
1717         ) );
1718         return substr( $text, 1 );
1719 }
1720
1721 /**
1722  * Get the current unix timetstamp with microseconds.  Useful for profiling
1723  * @return Float
1724  */
1725 function wfTime() {
1726         return microtime( true );
1727 }
1728
1729 /**
1730  * Sets dest to source and returns the original value of dest
1731  * If source is NULL, it just returns the value, it doesn't set the variable
1732  * If force is true, it will set the value even if source is NULL
1733  *
1734  * @param $dest Mixed
1735  * @param $source Mixed
1736  * @param $force Bool
1737  * @return Mixed
1738  */
1739 function wfSetVar( &$dest, $source, $force = false ) {
1740         $temp = $dest;
1741         if ( !is_null( $source ) || $force ) {
1742                 $dest = $source;
1743         }
1744         return $temp;
1745 }
1746
1747 /**
1748  * As for wfSetVar except setting a bit
1749  *
1750  * @param $dest Int
1751  * @param $bit Int
1752  * @param $state Bool
1753  */
1754 function wfSetBit( &$dest, $bit, $state = true ) {
1755         $temp = (bool)( $dest & $bit );
1756         if ( !is_null( $state ) ) {
1757                 if ( $state ) {
1758                         $dest |= $bit;
1759                 } else {
1760                         $dest &= ~$bit;
1761                 }
1762         }
1763         return $temp;
1764 }
1765
1766 /**
1767  * Windows-compatible version of escapeshellarg()
1768  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
1769  * function puts single quotes in regardless of OS.
1770  *
1771  * Also fixes the locale problems on Linux in PHP 5.2.6+ (bug backported to
1772  * earlier distro releases of PHP)
1773  *
1774  * @param varargs
1775  * @return String
1776  */
1777 function wfEscapeShellArg( ) {
1778         wfInitShellLocale();
1779
1780         $args = func_get_args();
1781         $first = true;
1782         $retVal = '';
1783         foreach ( $args as $arg ) {
1784                 if ( !$first ) {
1785                         $retVal .= ' ';
1786                 } else {
1787                         $first = false;
1788                 }
1789
1790                 if ( wfIsWindows() ) {
1791                         // Escaping for an MSVC-style command line parser and CMD.EXE
1792                         // Refs:
1793                         //  * http://web.archive.org/web/20020708081031/http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
1794                         //  * http://technet.microsoft.com/en-us/library/cc723564.aspx
1795                         //  * Bug #13518
1796                         //  * CR r63214
1797                         // Double the backslashes before any double quotes. Escape the double quotes.
1798                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
1799                         $arg = '';
1800                         $iteration = 0;
1801                         foreach ( $tokens as $token ) {
1802                                 if ( $iteration % 2 == 1 ) {
1803                                         // Delimiter, a double quote preceded by zero or more slashes
1804                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
1805                                 } elseif ( $iteration % 4 == 2 ) {
1806                                         // ^ in $token will be outside quotes, need to be escaped
1807                                         $arg .= str_replace( '^', '^^', $token );
1808                                 } else { // $iteration % 4 == 0
1809                                         // ^ in $token will appear inside double quotes, so leave as is
1810                                         $arg .= $token;
1811                                 }
1812                                 $iteration++;
1813                         }
1814                         // Double the backslashes before the end of the string, because
1815                         // we will soon add a quote
1816                         $m = array();
1817                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
1818                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
1819                         }
1820
1821                         // Add surrounding quotes
1822                         $retVal .= '"' . $arg . '"';
1823                 } else {
1824                         $retVal .= escapeshellarg( $arg );
1825                 }
1826         }
1827         return $retVal;
1828 }
1829
1830 /**
1831  * wfMerge attempts to merge differences between three texts.
1832  * Returns true for a clean merge and false for failure or a conflict.
1833  *
1834  * @param $old String
1835  * @param $mine String
1836  * @param $yours String
1837  * @param $result String
1838  * @return Bool
1839  */
1840 function wfMerge( $old, $mine, $yours, &$result ) {
1841         global $wgDiff3;
1842
1843         # This check may also protect against code injection in
1844         # case of broken installations.
1845         wfSuppressWarnings();
1846         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
1847         wfRestoreWarnings();
1848
1849         if( !$haveDiff3 ) {
1850                 wfDebug( "diff3 not found\n" );
1851                 return false;
1852         }
1853
1854         # Make temporary files
1855         $td = wfTempDir();
1856         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1857         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
1858         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
1859
1860         fwrite( $oldtextFile, $old );
1861         fclose( $oldtextFile );
1862         fwrite( $mytextFile, $mine );
1863         fclose( $mytextFile );
1864         fwrite( $yourtextFile, $yours );
1865         fclose( $yourtextFile );
1866
1867         # Check for a conflict
1868         $cmd = $wgDiff3 . ' -a --overlap-only ' .
1869                 wfEscapeShellArg( $mytextName ) . ' ' .
1870                 wfEscapeShellArg( $oldtextName ) . ' ' .
1871                 wfEscapeShellArg( $yourtextName );
1872         $handle = popen( $cmd, 'r' );
1873
1874         if( fgets( $handle, 1024 ) ) {
1875                 $conflict = true;
1876         } else {
1877                 $conflict = false;
1878         }
1879         pclose( $handle );
1880
1881         # Merge differences
1882         $cmd = $wgDiff3 . ' -a -e --merge ' .
1883                 wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
1884         $handle = popen( $cmd, 'r' );
1885         $result = '';
1886         do {
1887                 $data = fread( $handle, 8192 );
1888                 if ( strlen( $data ) == 0 ) {
1889                         break;
1890                 }
1891                 $result .= $data;
1892         } while ( true );
1893         pclose( $handle );
1894         unlink( $mytextName );
1895         unlink( $oldtextName );
1896         unlink( $yourtextName );
1897
1898         if ( $result === '' && $old !== '' && !$conflict ) {
1899                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
1900                 $conflict = true;
1901         }
1902         return !$conflict;
1903 }
1904
1905 /**
1906  * Returns unified plain-text diff of two texts.
1907  * Useful for machine processing of diffs.
1908  *
1909  * @param $before String: the text before the changes.
1910  * @param $after String: the text after the changes.
1911  * @param $params String: command-line options for the diff command.
1912  * @return String: unified diff of $before and $after
1913  */
1914 function wfDiff( $before, $after, $params = '-u' ) {
1915         if ( $before == $after ) {
1916                 return '';
1917         }
1918
1919         global $wgDiff;
1920         wfSuppressWarnings();
1921         $haveDiff = $wgDiff && file_exists( $wgDiff );
1922         wfRestoreWarnings();
1923
1924         # This check may also protect against code injection in
1925         # case of broken installations.
1926         if( !$haveDiff ) {
1927                 wfDebug( "diff executable not found\n" );
1928                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
1929                 $format = new UnifiedDiffFormatter();
1930                 return $format->format( $diffs );
1931         }
1932
1933         # Make temporary files
1934         $td = wfTempDir();
1935         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1936         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
1937
1938         fwrite( $oldtextFile, $before );
1939         fclose( $oldtextFile );
1940         fwrite( $newtextFile, $after );
1941         fclose( $newtextFile );
1942
1943         // Get the diff of the two files
1944         $cmd = "$wgDiff " . $params . ' ' . wfEscapeShellArg( $oldtextName, $newtextName );
1945
1946         $h = popen( $cmd, 'r' );
1947
1948         $diff = '';
1949
1950         do {
1951                 $data = fread( $h, 8192 );
1952                 if ( strlen( $data ) == 0 ) {
1953                         break;
1954                 }
1955                 $diff .= $data;
1956         } while ( true );
1957
1958         // Clean up
1959         pclose( $h );
1960         unlink( $oldtextName );
1961         unlink( $newtextName );
1962
1963         // Kill the --- and +++ lines. They're not useful.
1964         $diff_lines = explode( "\n", $diff );
1965         if ( strpos( $diff_lines[0], '---' ) === 0 ) {
1966                 unset( $diff_lines[0] );
1967         }
1968         if ( strpos( $diff_lines[1], '+++' ) === 0 ) {
1969                 unset( $diff_lines[1] );
1970         }
1971
1972         $diff = implode( "\n", $diff_lines );
1973
1974         return $diff;
1975 }
1976
1977 /**
1978  * A wrapper around the PHP function var_export().
1979  * Either print it or add it to the regular output ($wgOut).
1980  *
1981  * @param $var A PHP variable to dump.
1982  */
1983 function wfVarDump( $var ) {
1984         global $wgOut;
1985         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
1986         if ( headers_sent() || !isset( $wgOut ) || !is_object( $wgOut ) ) {
1987                 print $s;
1988         } else {
1989                 $wgOut->addHTML( $s );
1990         }
1991 }
1992
1993 /**
1994  * Provide a simple HTTP error.
1995  *
1996  * @param $code Int|String
1997  * @param $label String
1998  * @param $desc String
1999  */
2000 function wfHttpError( $code, $label, $desc ) {
2001         global $wgOut;
2002         $wgOut->disable();
2003         header( "HTTP/1.0 $code $label" );
2004         header( "Status: $code $label" );
2005         $wgOut->sendCacheControl();
2006
2007         header( 'Content-type: text/html; charset=utf-8' );
2008         print "<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">".
2009                 '<html><head><title>' .
2010                 htmlspecialchars( $label ) .
2011                 '</title></head><body><h1>' .
2012                 htmlspecialchars( $label ) .
2013                 '</h1><p>' .
2014                 nl2br( htmlspecialchars( $desc ) ) .
2015                 "</p></body></html>\n";
2016 }
2017
2018 /**
2019  * Clear away any user-level output buffers, discarding contents.
2020  *
2021  * Suitable for 'starting afresh', for instance when streaming
2022  * relatively large amounts of data without buffering, or wanting to
2023  * output image files without ob_gzhandler's compression.
2024  *
2025  * The optional $resetGzipEncoding parameter controls suppression of
2026  * the Content-Encoding header sent by ob_gzhandler; by default it
2027  * is left. See comments for wfClearOutputBuffers() for why it would
2028  * be used.
2029  *
2030  * Note that some PHP configuration options may add output buffer
2031  * layers which cannot be removed; these are left in place.
2032  *
2033  * @param $resetGzipEncoding Bool
2034  */
2035 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
2036         if( $resetGzipEncoding ) {
2037                 // Suppress Content-Encoding and Content-Length
2038                 // headers from 1.10+s wfOutputHandler
2039                 global $wgDisableOutputCompression;
2040                 $wgDisableOutputCompression = true;
2041         }
2042         while( $status = ob_get_status() ) {
2043                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
2044                         // Probably from zlib.output_compression or other
2045                         // PHP-internal setting which can't be removed.
2046                         //
2047                         // Give up, and hope the result doesn't break
2048                         // output behavior.
2049                         break;
2050                 }
2051                 if( !ob_end_clean() ) {
2052                         // Could not remove output buffer handler; abort now
2053                         // to avoid getting in some kind of infinite loop.
2054                         break;
2055                 }
2056                 if( $resetGzipEncoding ) {
2057                         if( $status['name'] == 'ob_gzhandler' ) {
2058                                 // Reset the 'Content-Encoding' field set by this handler
2059                                 // so we can start fresh.
2060                                 if ( function_exists( 'header_remove' ) ) {
2061                                         // Available since PHP 5.3.0
2062                                         header_remove( 'Content-Encoding' );
2063                                 } else {
2064                                         // We need to provide a valid content-coding. See bug 28069
2065                                         header( 'Content-Encoding: identity' );
2066                                 }
2067                                 break;
2068                         }
2069                 }
2070         }
2071 }
2072
2073 /**
2074  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
2075  *
2076  * Clear away output buffers, but keep the Content-Encoding header
2077  * produced by ob_gzhandler, if any.
2078  *
2079  * This should be used for HTTP 304 responses, where you need to
2080  * preserve the Content-Encoding header of the real result, but
2081  * also need to suppress the output of ob_gzhandler to keep to spec
2082  * and avoid breaking Firefox in rare cases where the headers and
2083  * body are broken over two packets.
2084  */
2085 function wfClearOutputBuffers() {
2086         wfResetOutputBuffers( false );
2087 }
2088
2089 /**
2090  * Converts an Accept-* header into an array mapping string values to quality
2091  * factors
2092  *
2093  * @param $accept String
2094  * @param $def String default
2095  * @return Array
2096  */
2097 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
2098         # No arg means accept anything (per HTTP spec)
2099         if( !$accept ) {
2100                 return array( $def => 1.0 );
2101         }
2102
2103         $prefs = array();
2104
2105         $parts = explode( ',', $accept );
2106
2107         foreach( $parts as $part ) {
2108                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
2109                 $values = explode( ';', trim( $part ) );
2110                 $match = array();
2111                 if ( count( $values ) == 1 ) {
2112                         $prefs[$values[0]] = 1.0;
2113                 } elseif ( preg_match( '/q\s*=\s*(\d*\.\d+)/', $values[1], $match ) ) {
2114                         $prefs[$values[0]] = floatval( $match[1] );
2115                 }
2116         }
2117
2118         return $prefs;
2119 }
2120
2121 /**
2122  * Checks if a given MIME type matches any of the keys in the given
2123  * array. Basic wildcards are accepted in the array keys.
2124  *
2125  * Returns the matching MIME type (or wildcard) if a match, otherwise
2126  * NULL if no match.
2127  *
2128  * @param $type String
2129  * @param $avail Array
2130  * @return string
2131  * @private
2132  */
2133 function mimeTypeMatch( $type, $avail ) {
2134         if( array_key_exists( $type, $avail ) ) {
2135                 return $type;
2136         } else {
2137                 $parts = explode( '/', $type );
2138                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
2139                         return $parts[0] . '/*';
2140                 } elseif( array_key_exists( '*/*', $avail ) ) {
2141                         return '*/*';
2142                 } else {
2143                         return null;
2144                 }
2145         }
2146 }
2147
2148 /**
2149  * Returns the 'best' match between a client's requested internet media types
2150  * and the server's list of available types. Each list should be an associative
2151  * array of type to preference (preference is a float between 0.0 and 1.0).
2152  * Wildcards in the types are acceptable.
2153  *
2154  * @param $cprefs Array: client's acceptable type list
2155  * @param $sprefs Array: server's offered types
2156  * @return string
2157  *
2158  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
2159  * XXX: generalize to negotiate other stuff
2160  */
2161 function wfNegotiateType( $cprefs, $sprefs ) {
2162         $combine = array();
2163
2164         foreach( array_keys( $sprefs ) as $type ) {
2165                 $parts = explode( '/', $type );
2166                 if( $parts[1] != '*' ) {
2167                         $ckey = mimeTypeMatch( $type, $cprefs );
2168                         if( $ckey ) {
2169                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
2170                         }
2171                 }
2172         }
2173
2174         foreach( array_keys( $cprefs ) as $type ) {
2175                 $parts = explode( '/', $type );
2176                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
2177                         $skey = mimeTypeMatch( $type, $sprefs );
2178                         if( $skey ) {
2179                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
2180                         }
2181                 }
2182         }
2183
2184         $bestq = 0;
2185         $besttype = null;
2186
2187         foreach( array_keys( $combine ) as $type ) {
2188                 if( $combine[$type] > $bestq ) {
2189                         $besttype = $type;
2190                         $bestq = $combine[$type];
2191                 }
2192         }
2193
2194         return $besttype;
2195 }
2196
2197 /**
2198  * Reference-counted warning suppression
2199  *
2200  * @param $end Bool
2201  */
2202 function wfSuppressWarnings( $end = false ) {
2203         static $suppressCount = 0;
2204         static $originalLevel = false;
2205
2206         if ( $end ) {
2207                 if ( $suppressCount ) {
2208                         --$suppressCount;
2209                         if ( !$suppressCount ) {
2210                                 error_reporting( $originalLevel );
2211                         }
2212                 }
2213         } else {
2214                 if ( !$suppressCount ) {
2215                         // E_DEPRECATED is undefined in PHP 5.2
2216                         if( !defined( 'E_DEPRECATED' ) ) {
2217                                 define( 'E_DEPRECATED', 8192 );
2218                         }
2219                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE | E_USER_WARNING | E_USER_NOTICE | E_DEPRECATED ) );
2220                 }
2221                 ++$suppressCount;
2222         }
2223 }
2224
2225 /**
2226  * Restore error level to previous value
2227  */
2228 function wfRestoreWarnings() {
2229         wfSuppressWarnings( true );
2230 }
2231
2232 # Autodetect, convert and provide timestamps of various types
2233
2234 /**
2235  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
2236  */
2237 define( 'TS_UNIX', 0 );
2238
2239 /**
2240  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
2241  */
2242 define( 'TS_MW', 1 );
2243
2244 /**
2245  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
2246  */
2247 define( 'TS_DB', 2 );
2248
2249 /**
2250  * RFC 2822 format, for E-mail and HTTP headers
2251  */
2252 define( 'TS_RFC2822', 3 );
2253
2254 /**
2255  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
2256  *
2257  * This is used by Special:Export
2258  */
2259 define( 'TS_ISO_8601', 4 );
2260
2261 /**
2262  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
2263  *
2264  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
2265  *       DateTime tag and page 36 for the DateTimeOriginal and
2266  *       DateTimeDigitized tags.
2267  */
2268 define( 'TS_EXIF', 5 );
2269
2270 /**
2271  * Oracle format time.
2272  */
2273 define( 'TS_ORACLE', 6 );
2274
2275 /**
2276  * Postgres format time.
2277  */
2278 define( 'TS_POSTGRES', 7 );
2279
2280 /**
2281  * DB2 format time
2282  */
2283 define( 'TS_DB2', 8 );
2284
2285 /**
2286  * ISO 8601 basic format with no timezone: 19860209T200000Z.  This is used by ResourceLoader
2287  */
2288 define( 'TS_ISO_8601_BASIC', 9 );
2289
2290 /**
2291  * Get a timestamp string in one of various formats
2292  *
2293  * @param $outputtype Mixed: A timestamp in one of the supported formats, the
2294  *                    function will autodetect which format is supplied and act
2295  *                    accordingly.
2296  * @param $ts Mixed: the timestamp to convert or 0 for the current timestamp
2297  * @return Mixed: String / false The same date in the format specified in $outputtype or false
2298  */
2299 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
2300         $uts = 0;
2301         $da = array();
2302         $strtime = '';
2303
2304         if ( !$ts ) { // We want to catch 0, '', null... but not date strings starting with a letter.
2305                 $uts = time();
2306                 $strtime = "@$uts";
2307         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2308                 # TS_DB
2309         } elseif ( preg_match( '/^(\d{4}):(\d\d):(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2310                 # TS_EXIF
2311         } elseif ( preg_match( '/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/D', $ts, $da ) ) {
2312                 # TS_MW
2313         } elseif ( preg_match( '/^-?\d{1,13}$/D', $ts ) ) {
2314                 # TS_UNIX
2315                 $uts = $ts;
2316                 $strtime = "@$ts"; // Undocumented?
2317         } elseif ( preg_match( '/^\d{2}-\d{2}-\d{4} \d{2}:\d{2}:\d{2}.\d{6}$/', $ts ) ) {
2318                 # TS_ORACLE // session altered to DD-MM-YYYY HH24:MI:SS.FF6
2319                 $strtime = preg_replace( '/(\d\d)\.(\d\d)\.(\d\d)(\.(\d+))?/', "$1:$2:$3",
2320                                 str_replace( '+00:00', 'UTC', $ts ) );
2321         } elseif ( preg_match( '/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2322                 # TS_ISO_8601
2323         } elseif ( preg_match( '/^(\d{4})(\d{2})(\d{2})T(\d{2})(\d{2})(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2324                 #TS_ISO_8601_BASIC
2325         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d*[\+\- ](\d\d)$/', $ts, $da ) ) {
2326                 # TS_POSTGRES
2327         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d* GMT$/', $ts, $da ) ) {
2328                 # TS_POSTGRES
2329         } elseif (preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.\d\d\d$/', $ts, $da ) ) {
2330                 # TS_DB2
2331         } elseif ( preg_match( '/^[ \t\r\n]*([A-Z][a-z]{2},[ \t\r\n]*)?' . # Day of week
2332                                                         '\d\d?[ \t\r\n]*[A-Z][a-z]{2}[ \t\r\n]*\d{2}(?:\d{2})?' .  # dd Mon yyyy
2333                                                         '[ \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
2334                 # TS_RFC2822, accepting a trailing comment. See http://www.squid-cache.org/mail-archive/squid-users/200307/0122.html / r77171
2335                 # The regex is a superset of rfc2822 for readability
2336                 $strtime = strtok( $ts, ';' );
2337         } 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 ) ) {
2338                 # TS_RFC850
2339                 $strtime = $ts;
2340         } 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 ) ) {
2341                 # asctime
2342                 $strtime = $ts;
2343         } else {
2344                 # Bogus value...
2345                 wfDebug("wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n");
2346
2347                 return false;
2348         }
2349
2350         static $formats = array(
2351                 TS_UNIX => 'U',
2352                 TS_MW => 'YmdHis',
2353                 TS_DB => 'Y-m-d H:i:s',
2354                 TS_ISO_8601 => 'Y-m-d\TH:i:s\Z',
2355                 TS_ISO_8601_BASIC => 'Ymd\THis\Z',
2356                 TS_EXIF => 'Y:m:d H:i:s', // This shouldn't ever be used, but is included for completeness
2357                 TS_RFC2822 => 'D, d M Y H:i:s',
2358                 TS_ORACLE => 'd-m-Y H:i:s.000000', // Was 'd-M-y h.i.s A' . ' +00:00' before r51500
2359                 TS_POSTGRES => 'Y-m-d H:i:s',
2360                 TS_DB2 => 'Y-m-d H:i:s',
2361         );
2362
2363         if ( !isset( $formats[$outputtype] ) ) {
2364                 throw new MWException( 'wfTimestamp() called with illegal output type.' );
2365         }
2366
2367         if ( function_exists( "date_create" ) ) {
2368                 if ( count( $da ) ) {
2369                         $ds = sprintf("%04d-%02d-%02dT%02d:%02d:%02d.00+00:00",
2370                                 (int)$da[1], (int)$da[2], (int)$da[3],
2371                                 (int)$da[4], (int)$da[5], (int)$da[6]);
2372
2373                         $d = date_create( $ds, new DateTimeZone( 'GMT' ) );
2374                 } elseif ( $strtime ) {
2375                         $d = date_create( $strtime, new DateTimeZone( 'GMT' ) );
2376                 } else {
2377                         return false;
2378                 }
2379
2380                 if ( !$d ) {
2381                         wfDebug("wfTimestamp() fed bogus time value: $outputtype; $ts\n");
2382                         return false;
2383                 }
2384
2385                 $output = $d->format( $formats[$outputtype] );
2386         } else {
2387                 if ( count( $da ) ) {
2388                         // Warning! gmmktime() acts oddly if the month or day is set to 0
2389                         // We may want to handle that explicitly at some point
2390                         $uts = gmmktime( (int)$da[4], (int)$da[5], (int)$da[6],
2391                                 (int)$da[2], (int)$da[3], (int)$da[1] );
2392                 } elseif ( $strtime ) {
2393                         $uts = strtotime( $strtime );
2394                 }
2395
2396                 if ( $uts === false ) {
2397                         wfDebug("wfTimestamp() can't parse the timestamp (non 32-bit time? Update php): $outputtype; $ts\n");
2398                         return false;
2399                 }
2400
2401                 if ( TS_UNIX == $outputtype ) {
2402                         return $uts;
2403                 }
2404                 $output = gmdate( $formats[$outputtype], $uts );
2405         }
2406
2407         if ( ( $outputtype == TS_RFC2822 ) || ( $outputtype == TS_POSTGRES ) ) {
2408                 $output .= ' GMT';
2409         }
2410
2411         return $output;
2412 }
2413
2414 /**
2415  * Return a formatted timestamp, or null if input is null.
2416  * For dealing with nullable timestamp columns in the database.
2417  *
2418  * @param $outputtype Integer
2419  * @param $ts String
2420  * @return String
2421  */
2422 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2423         if( is_null( $ts ) ) {
2424                 return null;
2425         } else {
2426                 return wfTimestamp( $outputtype, $ts );
2427         }
2428 }
2429
2430 /**
2431  * Convenience function; returns MediaWiki timestamp for the present time.
2432  *
2433  * @return string
2434  */
2435 function wfTimestampNow() {
2436         # return NOW
2437         return wfTimestamp( TS_MW, time() );
2438 }
2439
2440 /**
2441  * Check if the operating system is Windows
2442  *
2443  * @return Bool: true if it's Windows, False otherwise.
2444  */
2445 function wfIsWindows() {
2446         static $isWindows = null;
2447         if ( $isWindows === null ) {
2448                 $isWindows = substr( php_uname(), 0, 7 ) == 'Windows';
2449         }
2450         return $isWindows;
2451 }
2452
2453 /**
2454  * Check if we are running under HipHop
2455  *
2456  * @return Bool
2457  */
2458 function wfIsHipHop() {
2459         return function_exists( 'hphp_thread_set_warmup_enabled' );
2460 }
2461
2462 /**
2463  * Swap two variables
2464  *
2465  * @param $x Mixed
2466  * @param $y Mixed
2467  */
2468 function swap( &$x, &$y ) {
2469         $z = $x;
2470         $x = $y;
2471         $y = $z;
2472 }
2473
2474 /**
2475  * Tries to get the system directory for temporary files. The TMPDIR, TMP, and
2476  * TEMP environment variables are then checked in sequence, and if none are set
2477  * try sys_get_temp_dir() for PHP >= 5.2.1. All else fails, return /tmp for Unix
2478  * or C:\Windows\Temp for Windows and hope for the best.
2479  * It is common to call it with tempnam().
2480  *
2481  * NOTE: When possible, use instead the tmpfile() function to create
2482  * temporary files to avoid race conditions on file creation, etc.
2483  *
2484  * @return String
2485  */
2486 function wfTempDir() {
2487         foreach( array( 'TMPDIR', 'TMP', 'TEMP' ) as $var ) {
2488                 $tmp = getenv( $var );
2489                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
2490                         return $tmp;
2491                 }
2492         }
2493         if( function_exists( 'sys_get_temp_dir' ) ) {
2494                 return sys_get_temp_dir();
2495         }
2496         # Usual defaults
2497         return wfIsWindows() ? 'C:\Windows\Temp' : '/tmp';
2498 }
2499
2500 /**
2501  * Make directory, and make all parent directories if they don't exist
2502  *
2503  * @param $dir String: full path to directory to create
2504  * @param $mode Integer: chmod value to use, default is $wgDirectoryMode
2505  * @param $caller String: optional caller param for debugging.
2506  * @return bool
2507  */
2508 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2509         global $wgDirectoryMode;
2510
2511         if ( !is_null( $caller ) ) {
2512                 wfDebug( "$caller: called wfMkdirParents($dir)" );
2513         }
2514
2515         if( strval( $dir ) === '' || file_exists( $dir ) ) {
2516                 return true;
2517         }
2518
2519         $dir = str_replace( array( '\\', '/' ), DIRECTORY_SEPARATOR, $dir );
2520
2521         if ( is_null( $mode ) ) {
2522                 $mode = $wgDirectoryMode;
2523         }
2524
2525         // Turn off the normal warning, we're doing our own below
2526         wfSuppressWarnings();
2527         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2528         wfRestoreWarnings();
2529
2530         if( !$ok ) {
2531                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2532                 trigger_error( __FUNCTION__ . ": failed to mkdir \"$dir\" mode $mode", E_USER_WARNING );
2533         }
2534         return $ok;
2535 }
2536
2537 /**
2538  * Increment a statistics counter
2539  *
2540  * @param $key String
2541  * @param $count Int
2542  */
2543 function wfIncrStats( $key, $count = 1 ) {
2544         global $wgStatsMethod;
2545
2546         $count = intval( $count );
2547
2548         if( $wgStatsMethod == 'udp' ) {
2549                 global $wgUDPProfilerHost, $wgUDPProfilerPort, $wgDBname, $wgAggregateStatsID;
2550                 static $socket;
2551
2552                 $id = $wgAggregateStatsID !== false ? $wgAggregateStatsID : $wgDBname;
2553
2554                 if ( !$socket ) {
2555                         $socket = socket_create( AF_INET, SOCK_DGRAM, SOL_UDP );
2556                         $statline = "stats/{$id} - {$count} 1 1 1 1 -total\n";
2557                         socket_sendto(
2558                                 $socket,
2559                                 $statline,
2560                                 strlen( $statline ),
2561                                 0,
2562                                 $wgUDPProfilerHost,
2563                                 $wgUDPProfilerPort
2564                         );
2565                 }
2566                 $statline = "stats/{$id} - {$count} 1 1 1 1 {$key}\n";
2567                 wfSuppressWarnings();
2568                 socket_sendto(
2569                         $socket,
2570                         $statline,
2571                         strlen( $statline ),
2572                         0,
2573                         $wgUDPProfilerHost,
2574                         $wgUDPProfilerPort
2575                 );
2576                 wfRestoreWarnings();
2577         } elseif( $wgStatsMethod == 'cache' ) {
2578                 global $wgMemc;
2579                 $key = wfMemcKey( 'stats', $key );
2580                 if ( is_null( $wgMemc->incr( $key, $count ) ) ) {
2581                         $wgMemc->add( $key, $count );
2582                 }
2583         } else {
2584                 // Disabled
2585         }
2586 }
2587
2588 /**
2589  * @param $nr Mixed: the number to format
2590  * @param $acc Integer: the number of digits after the decimal point, default 2
2591  * @param $round Boolean: whether or not to round the value, default true
2592  * @return float
2593  */
2594 function wfPercent( $nr, $acc = 2, $round = true ) {
2595         $ret = sprintf( "%.${acc}f", $nr );
2596         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2597 }
2598
2599 /**
2600  * Find out whether or not a mixed variable exists in a string
2601  *
2602  * @param $needle String
2603  * @param $str String
2604  * @param $insensitive Boolean
2605  * @return Boolean
2606  */
2607 function in_string( $needle, $str, $insensitive = false ) {
2608         $func = 'strpos';
2609         if( $insensitive ) $func = 'stripos';
2610
2611         return $func( $str, $needle ) !== false;
2612 }
2613
2614 /**
2615  * Make a list item, used by various special pages
2616  *
2617  * @param $page String Page link
2618  * @param $details String Text between brackets
2619  * @param $oppositedm Boolean   Add the direction mark opposite to your
2620  *                                                              language, to display text properly
2621  * @return String
2622  * @deprecated since 1.19; use Language::specialList() instead
2623  */
2624 function wfSpecialList( $page, $details, $oppositedm = true ) {
2625         global $wgLang;
2626         return $wgLang->specialList( $page, $details, $oppositedm );
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  * Generate a shell-escaped command line string to run a maintenance script.
2807  * Note that $parameters should be a flat array and an option with an argument
2808  * should consist of two consecutive items in the array (do not use "--option value").
2809  * @param $script string MediaWiki maintenance script path
2810  * @param $parameters Array Arguments and options to the script
2811  * @param $options Array Associative array of options:
2812  *              'php': The path to the php executable
2813  *              'wrapper': Path to a PHP wrapper to handle the maintenance script
2814  * @return Array
2815  */
2816 function wfShellMaintenanceCmd( $script, array $parameters = array(), array $options = array() ) {
2817         global $wgPhpCli;
2818         // Give site config file a chance to run the script in a wrapper.
2819         // The caller may likely want to call wfBasename() on $script.
2820         wfRunHooks( 'wfShellMaintenanceCmd', array( &$script, &$parameters, &$options ) );
2821         $cmd = isset( $options['php'] ) ? array( $options['php'] ) : array( $wgPhpCli );
2822         if ( isset( $options['wrapper'] ) ) {
2823                 $cmd[] = $options['wrapper'];
2824         }
2825         $cmd[] = $script;
2826         // Escape each parameter for shell
2827         return implode( " ", array_map( 'wfEscapeShellArg', array_merge( $cmd, $parameters ) ) );
2828 }
2829
2830 /**
2831  * This function works like "use VERSION" in Perl, the program will die with a
2832  * backtrace if the current version of PHP is less than the version provided
2833  *
2834  * This is useful for extensions which due to their nature are not kept in sync
2835  * with releases, and might depend on other versions of PHP than the main code
2836  *
2837  * Note: PHP might die due to parsing errors in some cases before it ever
2838  *       manages to call this function, such is life
2839  *
2840  * @see perldoc -f use
2841  *
2842  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2843  *                 a float
2844  */
2845 function wfUsePHP( $req_ver ) {
2846         $php_ver = PHP_VERSION;
2847
2848         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
2849                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
2850         }
2851 }
2852
2853 /**
2854  * This function works like "use VERSION" in Perl except it checks the version
2855  * of MediaWiki, the program will die with a backtrace if the current version
2856  * of MediaWiki is less than the version provided.
2857  *
2858  * This is useful for extensions which due to their nature are not kept in sync
2859  * with releases
2860  *
2861  * @see perldoc -f use
2862  *
2863  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2864  *                 a float
2865  */
2866 function wfUseMW( $req_ver ) {
2867         global $wgVersion;
2868
2869         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
2870                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
2871         }
2872 }
2873
2874 /**
2875  * Return the final portion of a pathname.
2876  * Reimplemented because PHP5's basename() is buggy with multibyte text.
2877  * http://bugs.php.net/bug.php?id=33898
2878  *
2879  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
2880  * We'll consider it so always, as we don't want \s in our Unix paths either.
2881  *
2882  * @param $path String
2883  * @param $suffix String: to remove if present
2884  * @return String
2885  */
2886 function wfBaseName( $path, $suffix = '' ) {
2887         $encSuffix = ( $suffix == '' )
2888                 ? ''
2889                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
2890         $matches = array();
2891         if( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2892                 return $matches[1];
2893         } else {
2894                 return '';
2895         }
2896 }
2897
2898 /**
2899  * Generate a relative path name to the given file.
2900  * May explode on non-matching case-insensitive paths,
2901  * funky symlinks, etc.
2902  *
2903  * @param $path String: absolute destination path including target filename
2904  * @param $from String: Absolute source path, directory only
2905  * @return String
2906  */
2907 function wfRelativePath( $path, $from ) {
2908         // Normalize mixed input on Windows...
2909         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2910         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2911
2912         // Trim trailing slashes -- fix for drive root
2913         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2914         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2915
2916         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2917         $against = explode( DIRECTORY_SEPARATOR, $from );
2918
2919         if( $pieces[0] !== $against[0] ) {
2920                 // Non-matching Windows drive letters?
2921                 // Return a full path.
2922                 return $path;
2923         }
2924
2925         // Trim off common prefix
2926         while( count( $pieces ) && count( $against )
2927                 && $pieces[0] == $against[0] ) {
2928                 array_shift( $pieces );
2929                 array_shift( $against );
2930         }
2931
2932         // relative dots to bump us to the parent
2933         while( count( $against ) ) {
2934                 array_unshift( $pieces, '..' );
2935                 array_shift( $against );
2936         }
2937
2938         array_push( $pieces, wfBaseName( $path ) );
2939
2940         return implode( DIRECTORY_SEPARATOR, $pieces );
2941 }
2942
2943 /**
2944  * Do any deferred updates and clear the list
2945  *
2946  * @deprecated since 1.19
2947  * @see DeferredUpdates::doUpdate()
2948  */
2949 function wfDoUpdates( $commit = '' ) {
2950         DeferredUpdates::doUpdates( $commit );
2951 }
2952
2953 /**
2954  * Convert an arbitrarily-long digit string from one numeric base
2955  * to another, optionally zero-padding to a minimum column width.
2956  *
2957  * Supports base 2 through 36; digit values 10-36 are represented
2958  * as lowercase letters a-z. Input is case-insensitive.
2959  *
2960  * @param $input String: of digits
2961  * @param $sourceBase Integer: 2-36
2962  * @param $destBase Integer: 2-36
2963  * @param $pad Integer: 1 or greater
2964  * @param $lowercase Boolean
2965  * @return String or false on invalid input
2966  */
2967 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1, $lowercase = true ) {
2968         $input = strval( $input );
2969         if( $sourceBase < 2 ||
2970                 $sourceBase > 36 ||
2971                 $destBase < 2 ||
2972                 $destBase > 36 ||
2973                 $pad < 1 ||
2974                 $sourceBase != intval( $sourceBase ) ||
2975                 $destBase != intval( $destBase ) ||
2976                 $pad != intval( $pad ) ||
2977                 !is_string( $input ) ||
2978                 $input == '' ) {
2979                 return false;
2980         }
2981         $digitChars = ( $lowercase ) ? '0123456789abcdefghijklmnopqrstuvwxyz' : '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
2982         $inDigits = array();
2983         $outChars = '';
2984
2985         // Decode and validate input string
2986         $input = strtolower( $input );
2987         for( $i = 0; $i < strlen( $input ); $i++ ) {
2988                 $n = strpos( $digitChars, $input[$i] );
2989                 if( $n === false || $n > $sourceBase ) {
2990                         return false;
2991                 }
2992                 $inDigits[] = $n;
2993         }
2994
2995         // Iterate over the input, modulo-ing out an output digit
2996         // at a time until input is gone.
2997         while( count( $inDigits ) ) {
2998                 $work = 0;
2999                 $workDigits = array();
3000
3001                 // Long division...
3002                 foreach( $inDigits as $digit ) {
3003                         $work *= $sourceBase;
3004                         $work += $digit;
3005
3006                         if( $work < $destBase ) {
3007                                 // Gonna need to pull another digit.
3008                                 if( count( $workDigits ) ) {
3009                                         // Avoid zero-padding; this lets us find
3010                                         // the end of the input very easily when
3011                                         // length drops to zero.
3012                                         $workDigits[] = 0;
3013                                 }
3014                         } else {
3015                                 // Finally! Actual division!
3016                                 $workDigits[] = intval( $work / $destBase );
3017
3018                                 // Isn't it annoying that most programming languages
3019                                 // don't have a single divide-and-remainder operator,
3020                                 // even though the CPU implements it that way?
3021                                 $work = $work % $destBase;
3022                         }
3023                 }
3024
3025                 // All that division leaves us with a remainder,
3026                 // which is conveniently our next output digit.
3027                 $outChars .= $digitChars[$work];
3028
3029                 // And we continue!
3030                 $inDigits = $workDigits;
3031         }
3032
3033         while( strlen( $outChars ) < $pad ) {
3034                 $outChars .= '0';
3035         }
3036
3037         return strrev( $outChars );
3038 }
3039
3040 /**
3041  * Create an object with a given name and an array of construct parameters
3042  *
3043  * @param $name String
3044  * @param $p Array: parameters
3045  * @deprecated since 1.18, warnings in 1.18, removal in 1.20
3046  */
3047 function wfCreateObject( $name, $p ) {
3048         wfDeprecated( __FUNCTION__ );
3049         return MWFunction::newObj( $name, $p );
3050 }
3051
3052 function wfHttpOnlySafe() {
3053         global $wgHttpOnlyBlacklist;
3054
3055         if( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
3056                 foreach( $wgHttpOnlyBlacklist as $regex ) {
3057                         if( preg_match( $regex, $_SERVER['HTTP_USER_AGENT'] ) ) {
3058                                 return false;
3059                         }
3060                 }
3061         }
3062
3063         return true;
3064 }
3065
3066 /**
3067  * Initialise php session
3068  *
3069  * @param $sessionId Bool
3070  */
3071 function wfSetupSession( $sessionId = false ) {
3072         global $wgSessionsInMemcached, $wgCookiePath, $wgCookieDomain,
3073                         $wgCookieSecure, $wgCookieHttpOnly, $wgSessionHandler;
3074         if( $wgSessionsInMemcached ) {
3075                 if ( !defined( 'MW_COMPILED' ) ) {
3076                         global $IP;
3077                         require_once( "$IP/includes/cache/MemcachedSessions.php" );
3078                 }
3079                 session_set_save_handler( 'memsess_open', 'memsess_close', 'memsess_read',
3080                         'memsess_write', 'memsess_destroy', 'memsess_gc' );
3081
3082                 // It's necessary to register a shutdown function to call session_write_close(),
3083                 // because by the time the request shutdown function for the session module is
3084                 // called, $wgMemc has already been destroyed. Shutdown functions registered
3085                 // this way are called before object destruction.
3086                 register_shutdown_function( 'memsess_write_close' );
3087         } elseif( $wgSessionHandler && $wgSessionHandler != ini_get( 'session.save_handler' ) ) {
3088                 # Only set this if $wgSessionHandler isn't null and session.save_handler
3089                 # hasn't already been set to the desired value (that causes errors)
3090                 ini_set( 'session.save_handler', $wgSessionHandler );
3091         }
3092         $httpOnlySafe = wfHttpOnlySafe() && $wgCookieHttpOnly;
3093         wfDebugLog( 'cookie',
3094                 'session_set_cookie_params: "' . implode( '", "',
3095                         array(
3096                                 0,
3097                                 $wgCookiePath,
3098                                 $wgCookieDomain,
3099                                 $wgCookieSecure,
3100                                 $httpOnlySafe ) ) . '"' );
3101         session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $httpOnlySafe );
3102         session_cache_limiter( 'private, must-revalidate' );
3103         if ( $sessionId ) {
3104                 session_id( $sessionId );
3105         }
3106         wfSuppressWarnings();
3107         session_start();
3108         wfRestoreWarnings();
3109 }
3110
3111 /**
3112  * Get an object from the precompiled serialized directory
3113  *
3114  * @param $name String
3115  * @return Mixed: the variable on success, false on failure
3116  */
3117 function wfGetPrecompiledData( $name ) {
3118         global $IP;
3119
3120         $file = "$IP/serialized/$name";
3121         if ( file_exists( $file ) ) {
3122                 $blob = file_get_contents( $file );
3123                 if ( $blob ) {
3124                         return unserialize( $blob );
3125                 }
3126         }
3127         return false;
3128 }
3129
3130 /**
3131  * Get a cache key
3132  *
3133  * @param varargs
3134  * @return String
3135  */
3136 function wfMemcKey( /*... */ ) {
3137         $args = func_get_args();
3138         $key = wfWikiID() . ':' . implode( ':', $args );
3139         $key = str_replace( ' ', '_', $key );
3140         return $key;
3141 }
3142
3143 /**
3144  * Get a cache key for a foreign DB
3145  *
3146  * @param $db String
3147  * @param $prefix String
3148  * @param varargs String
3149  * @return String
3150  */
3151 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
3152         $args = array_slice( func_get_args(), 2 );
3153         if ( $prefix ) {
3154                 $key = "$db-$prefix:" . implode( ':', $args );
3155         } else {
3156                 $key = $db . ':' . implode( ':', $args );
3157         }
3158         return $key;
3159 }
3160
3161 /**
3162  * Get an ASCII string identifying this wiki
3163  * This is used as a prefix in memcached keys
3164  *
3165  * @return String
3166  */
3167 function wfWikiID() {
3168         global $wgDBprefix, $wgDBname, $wgWikiID;
3169         if ( $wgWikiID !== false ) {
3170                 return $wgWikiID;
3171         } elseif ( $wgDBprefix ) {
3172                 return "$wgDBname-$wgDBprefix";
3173         } else {
3174                 return $wgDBname;
3175         }
3176 }
3177
3178 /**
3179  * Split a wiki ID into DB name and table prefix
3180  *
3181  * @param $wiki String
3182  * @param $bits String
3183  *
3184  * @return array
3185  */
3186 function wfSplitWikiID( $wiki ) {
3187         $bits = explode( '-', $wiki, 2 );
3188         if ( count( $bits ) < 2 ) {
3189                 $bits[] = '';
3190         }
3191         return $bits;
3192 }
3193
3194 /**
3195  * Get a Database object.
3196  *
3197  * @param $db Integer: index of the connection to get. May be DB_MASTER for the
3198  *            master (for write queries), DB_SLAVE for potentially lagged read
3199  *            queries, or an integer >= 0 for a particular server.
3200  *
3201  * @param $groups Mixed: query groups. An array of group names that this query
3202  *                belongs to. May contain a single string if the query is only
3203  *                in one group.
3204  *
3205  * @param $wiki String: the wiki ID, or false for the current wiki
3206  *
3207  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
3208  * will always return the same object, unless the underlying connection or load
3209  * balancer is manually destroyed.
3210  *
3211  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
3212  * updater to ensure that a proper database is being updated.
3213  *
3214  * @return DatabaseBase
3215  */
3216 function &wfGetDB( $db, $groups = array(), $wiki = false ) {
3217         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
3218 }
3219
3220 /**
3221  * Get a load balancer object.
3222  *
3223  * @param $wiki String: wiki ID, or false for the current wiki
3224  * @return LoadBalancer
3225  */
3226 function wfGetLB( $wiki = false ) {
3227         return wfGetLBFactory()->getMainLB( $wiki );
3228 }
3229
3230 /**
3231  * Get the load balancer factory object
3232  *
3233  * @return LBFactory
3234  */
3235 function &wfGetLBFactory() {
3236         return LBFactory::singleton();
3237 }
3238
3239 /**
3240  * Find a file.
3241  * Shortcut for RepoGroup::singleton()->findFile()
3242  *
3243  * @param $title String or Title object
3244  * @param $options Associative array of options:
3245  *     time:           requested time for an archived image, or false for the
3246  *                     current version. An image object will be returned which was
3247  *                     created at the specified time.
3248  *
3249  *     ignoreRedirect: If true, do not follow file redirects
3250  *
3251  *     private:        If true, return restricted (deleted) files if the current
3252  *                     user is allowed to view them. Otherwise, such files will not
3253  *                     be found.
3254  *
3255  *     bypassCache:    If true, do not use the process-local cache of File objects
3256  *
3257  * @return File, or false if the file does not exist
3258  */
3259 function wfFindFile( $title, $options = array() ) {
3260         return RepoGroup::singleton()->findFile( $title, $options );
3261 }
3262
3263 /**
3264  * Get an object referring to a locally registered file.
3265  * Returns a valid placeholder object if the file does not exist.
3266  *
3267  * @param $title Title or String
3268  * @return File, or null if passed an invalid Title
3269  */
3270 function wfLocalFile( $title ) {
3271         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
3272 }
3273
3274 /**
3275  * Stream a file to the browser. Back-compat alias for StreamFile::stream()
3276  * @deprecated since 1.19
3277  */
3278 function wfStreamFile( $fname, $headers = array() ) {
3279         StreamFile::stream( $fname, $headers );
3280 }
3281
3282 /**
3283  * Should low-performance queries be disabled?
3284  *
3285  * @return Boolean
3286  * @codeCoverageIgnore
3287  */
3288 function wfQueriesMustScale() {
3289         global $wgMiserMode;
3290         return $wgMiserMode
3291                 || ( SiteStats::pages() > 100000
3292                 && SiteStats::edits() > 1000000
3293                 && SiteStats::users() > 10000 );
3294 }
3295
3296 /**
3297  * Get the path to a specified script file, respecting file
3298  * extensions; this is a wrapper around $wgScriptExtension etc.
3299  *
3300  * @param $script String: script filename, sans extension
3301  * @return String
3302  */
3303 function wfScript( $script = 'index' ) {
3304         global $wgScriptPath, $wgScriptExtension;
3305         return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
3306 }
3307
3308 /**
3309  * Get the script URL.
3310  *
3311  * @return script URL
3312  */
3313 function wfGetScriptUrl() {
3314         if( isset( $_SERVER['SCRIPT_NAME'] ) ) {
3315                 #
3316                 # as it was called, minus the query string.
3317                 #
3318                 # Some sites use Apache rewrite rules to handle subdomains,
3319                 # and have PHP set up in a weird way that causes PHP_SELF
3320                 # to contain the rewritten URL instead of the one that the
3321                 # outside world sees.
3322                 #
3323                 # If in this mode, use SCRIPT_URL instead, which mod_rewrite
3324                 # provides containing the "before" URL.
3325                 return $_SERVER['SCRIPT_NAME'];
3326         } else {
3327                 return $_SERVER['URL'];
3328         }
3329 }
3330
3331 /**
3332  * Convenience function converts boolean values into "true"
3333  * or "false" (string) values
3334  *
3335  * @param $value Boolean
3336  * @return String
3337  */
3338 function wfBoolToStr( $value ) {
3339         return $value ? 'true' : 'false';
3340 }
3341
3342 /**
3343  * Load an extension messages file
3344  *
3345  * @deprecated since 1.16, warnings in 1.18, remove in 1.20
3346  * @codeCoverageIgnore
3347  */
3348 function wfLoadExtensionMessages() {
3349         wfDeprecated( __FUNCTION__ );
3350 }
3351
3352 /**
3353  * Get a platform-independent path to the null file, e.g. /dev/null
3354  *
3355  * @return string
3356  */
3357 function wfGetNull() {
3358         return wfIsWindows()
3359                 ? 'NUL'
3360                 : '/dev/null';
3361 }
3362
3363 /**
3364  * Throws a warning that $function is deprecated
3365  *
3366  * @param $function String
3367  * @param $version String
3368  * @return null
3369  */
3370 function wfDeprecated( $function, $version = false ) {
3371         static $functionsWarned = array();
3372         if ( !isset( $functionsWarned[$function] ) ) {
3373                 $functionsWarned[$function] = true;
3374                 if ( $version ) {
3375                         global $wgDeprecationReleaseLimit;
3376                         if ( $wgDeprecationReleaseLimit ) {
3377                                 # Strip -* off the end of $version so that branches can use the
3378                                 # format #.##-branchname to avoid issues if the branch is merged into
3379                                 # a version of MediaWiki later than what it was branched from
3380                                 $comparableVersion = preg_replace( '/-.*$/', '', $version );
3381                                 # If the comparableVersion is larger than our release limit then
3382                                 # skip the warning message for the deprecation
3383                                 if ( version_compare( $wgDeprecationReleaseLimit, $comparableVersion, '<' ) ) {
3384                                         return;
3385                                 }
3386                         }
3387                         wfWarn( "Use of $function was deprecated in $version.", 2 );
3388                 } else {
3389                         wfWarn( "Use of $function is deprecated.", 2 );
3390                 }
3391         }
3392 }
3393
3394 /**
3395  * Send a warning either to the debug log or in a PHP error depending on
3396  * $wgDevelopmentWarnings
3397  *
3398  * @param $msg String: message to send
3399  * @param $callerOffset Integer: number of items to go back in the backtrace to
3400  *        find the correct caller (1 = function calling wfWarn, ...)
3401  * @param $level Integer: PHP error level; only used when $wgDevelopmentWarnings
3402  *        is true
3403  */
3404 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
3405         global $wgDevelopmentWarnings;
3406
3407         $callers = wfDebugBacktrace();
3408         if ( isset( $callers[$callerOffset + 1] ) ) {
3409                 $callerfunc = $callers[$callerOffset + 1];
3410                 $callerfile = $callers[$callerOffset];
3411                 if ( isset( $callerfile['file'] ) && isset( $callerfile['line'] ) ) {
3412                         $file = $callerfile['file'] . ' at line ' . $callerfile['line'];
3413                 } else {
3414                         $file = '(internal function)';
3415                 }
3416                 $func = '';
3417                 if ( isset( $callerfunc['class'] ) ) {
3418                         $func .= $callerfunc['class'] . '::';
3419                 }
3420                 if ( isset( $callerfunc['function'] ) ) {
3421                         $func .= $callerfunc['function'];
3422                 }
3423                 $msg .= " [Called from $func in $file]";
3424         }
3425
3426         if ( $wgDevelopmentWarnings ) {
3427                 trigger_error( $msg, $level );
3428         } else {
3429                 wfDebug( "$msg\n" );
3430         }
3431 }
3432
3433 /**
3434  * Modern version of wfWaitForSlaves(). Instead of looking at replication lag
3435  * and waiting for it to go down, this waits for the slaves to catch up to the
3436  * master position. Use this when updating very large numbers of rows, as
3437  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
3438  * a no-op if there are no slaves.
3439  *
3440  * @param $maxLag Integer (deprecated)
3441  * @param $wiki mixed Wiki identifier accepted by wfGetLB
3442  * @return null
3443  */
3444 function wfWaitForSlaves( $maxLag = false, $wiki = false ) {
3445         $lb = wfGetLB( $wiki );
3446         // bug 27975 - Don't try to wait for slaves if there are none
3447         // Prevents permission error when getting master position
3448         if ( $lb->getServerCount() > 1 ) {
3449                 $dbw = $lb->getConnection( DB_MASTER );
3450                 $pos = $dbw->getMasterPos();
3451                 $lb->waitForAll( $pos );
3452         }
3453 }
3454
3455 /**
3456  * Used to be used for outputting text in the installer/updater
3457  * @deprecated since 1.18, warnings in 1.18, remove in 1.20
3458  */
3459 function wfOut( $s ) {
3460         wfDeprecated( __METHOD__ );
3461         global $wgCommandLineMode;
3462         if ( $wgCommandLineMode ) {
3463                 echo $s;
3464         } else {
3465                 echo htmlspecialchars( $s );
3466         }
3467         flush();
3468 }
3469
3470 /**
3471  * Count down from $n to zero on the terminal, with a one-second pause
3472  * between showing each number. For use in command-line scripts.
3473  * @codeCoverageIgnore
3474  */
3475 function wfCountDown( $n ) {
3476         for ( $i = $n; $i >= 0; $i-- ) {
3477                 if ( $i != $n ) {
3478                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3479                 }
3480                 echo $i;
3481                 flush();
3482                 if ( $i ) {
3483                         sleep( 1 );
3484                 }
3485         }
3486         echo "\n";
3487 }
3488
3489 /**
3490  * Generate a random 32-character hexadecimal token.
3491  * @param $salt Mixed: some sort of salt, if necessary, to add to random
3492  *              characters before hashing.
3493  * @return string
3494  * @codeCoverageIgnore
3495  */
3496 function wfGenerateToken( $salt = '' ) {
3497         $salt = serialize( $salt );
3498         return md5( mt_rand( 0, 0x7fffffff ) . $salt );
3499 }
3500
3501 /**
3502  * Replace all invalid characters with -
3503  *
3504  * @param $name Mixed: filename to process
3505  * @return String
3506  */
3507 function wfStripIllegalFilenameChars( $name ) {
3508         global $wgIllegalFileChars;
3509         $name = wfBaseName( $name );
3510         $name = preg_replace(
3511                 "/[^" . Title::legalChars() . "]" .
3512                         ( $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '' ) .
3513                         "/",
3514                 '-',
3515                 $name
3516         );
3517         return $name;
3518 }
3519
3520 /**
3521  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit;
3522  *
3523  * @return Integer value memory was set to.
3524  */
3525 function wfMemoryLimit() {
3526         global $wgMemoryLimit;
3527         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3528         if( $memlimit != -1 ) {
3529                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3530                 if( $conflimit == -1 ) {
3531                         wfDebug( "Removing PHP's memory limit\n" );
3532                         wfSuppressWarnings();
3533                         ini_set( 'memory_limit', $conflimit );
3534                         wfRestoreWarnings();
3535                         return $conflimit;
3536                 } elseif ( $conflimit > $memlimit ) {
3537                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3538                         wfSuppressWarnings();
3539                         ini_set( 'memory_limit', $conflimit );
3540                         wfRestoreWarnings();
3541                         return $conflimit;
3542                 }
3543         }
3544         return $memlimit;
3545 }
3546
3547 /**
3548  * Converts shorthand byte notation to integer form
3549  *
3550  * @param $string String
3551  * @return Integer
3552  */
3553 function wfShorthandToInteger( $string = '' ) {
3554         $string = trim( $string );
3555         if( $string === '' ) {
3556                 return -1;
3557         }
3558         $last = $string[strlen( $string ) - 1];
3559         $val = intval( $string );
3560         switch( $last ) {
3561                 case 'g':
3562                 case 'G':
3563                         $val *= 1024;
3564                         // break intentionally missing
3565                 case 'm':
3566                 case 'M':
3567                         $val *= 1024;
3568                         // break intentionally missing
3569                 case 'k':
3570                 case 'K':
3571                         $val *= 1024;
3572         }
3573
3574         return $val;
3575 }
3576
3577 /**
3578  * Get the normalised IETF language tag
3579  * See unit test for examples.
3580  *
3581  * @param $code String: The language code.
3582  * @return $langCode String: The language code which complying with BCP 47 standards.
3583  */
3584 function wfBCP47( $code ) {
3585         $codeSegment = explode( '-', $code );
3586         $codeBCP = array();
3587         foreach ( $codeSegment as $segNo => $seg ) {
3588                 if ( count( $codeSegment ) > 0 ) {
3589                         // when previous segment is x, it is a private segment and should be lc
3590                         if( $segNo > 0 && strtolower( $codeSegment[( $segNo - 1 )] ) == 'x' ) {
3591                                 $codeBCP[$segNo] = strtolower( $seg );
3592                         // ISO 3166 country code
3593                         } elseif ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3594                                 $codeBCP[$segNo] = strtoupper( $seg );
3595                         // ISO 15924 script code
3596                         } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3597                                 $codeBCP[$segNo] = ucfirst( strtolower( $seg ) );
3598                         // Use lowercase for other cases
3599                         } else {
3600                                 $codeBCP[$segNo] = strtolower( $seg );
3601                         }
3602                 } else {
3603                 // Use lowercase for single segment
3604                         $codeBCP[$segNo] = strtolower( $seg );
3605                 }
3606         }
3607         $langCode = implode( '-', $codeBCP );
3608         return $langCode;
3609 }
3610
3611 /**
3612  * Get a cache object.
3613  *
3614  * @param $inputType integer Cache type, one the the CACHE_* constants.
3615  * @return BagOStuff
3616  */
3617 function wfGetCache( $inputType ) {
3618         return ObjectCache::getInstance( $inputType );
3619 }
3620
3621 /**
3622  * Get the main cache object
3623  *
3624  * @return BagOStuff
3625  */
3626 function wfGetMainCache() {
3627         global $wgMainCacheType;
3628         return ObjectCache::getInstance( $wgMainCacheType );
3629 }
3630
3631 /**
3632  * Get the cache object used by the message cache
3633  *
3634  * @return BagOStuff
3635  */
3636 function wfGetMessageCacheStorage() {
3637         global $wgMessageCacheType;
3638         return ObjectCache::getInstance( $wgMessageCacheType );
3639 }
3640
3641 /**
3642  * Get the cache object used by the parser cache
3643  *
3644  * @return BagOStuff
3645  */
3646 function wfGetParserCacheStorage() {
3647         global $wgParserCacheType;
3648         return ObjectCache::getInstance( $wgParserCacheType );
3649 }
3650
3651 /**
3652  * Call hook functions defined in $wgHooks
3653  *
3654  * @param $event String: event name
3655  * @param $args Array: parameters passed to hook functions
3656  * @return Boolean
3657  */
3658 function wfRunHooks( $event, $args = array() ) {
3659         return Hooks::run( $event, $args );
3660 }