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