includes/GlobalFunctions.php

   1 <?php
   2 # $Id$
   3
   4 /**
   5  * Global functions used everywhere
   6  * @package MediaWiki
   7  */
   8
   9 /**
  10  * Some globals and requires needed
  11  */
  12
  13 /**
  14  * Total number of articles
  15  * @global integer $wgNumberOfArticles
  16  */
  17 $wgNumberOfArticles = -1; # Unset
  18 /**
  19  * Total number of views
  20  * @global integer $wgTotalViews
  21  */
  22 $wgTotalViews = -1;
  23 /**
  24  * Total number of edits
  25  * @global integer $wgTotalEdits
  26  */
  27 $wgTotalEdits = -1;
  28
  29
  30 require_once( 'DatabaseFunctions.php' );
  31 require_once( 'UpdateClasses.php' );
  32 require_once( 'LogPage.php' );
  33
  34 /**
  35  * Compatibility functions
  36  * PHP <4.3.x is not actively supported; 4.1.x and 4.2.x might or might not work.
  37  * <4.1.x will not work, as we use a number of features introduced in 4.1.0
  38  * such as the new autoglobals.
  39 */
  40 if( !function_exists('iconv') ) {
  41         # iconv support is not in the default configuration and so may not be present.
  42         # Assume will only ever use utf-8 and iso-8859-1.
  43         # This will *not* work in all circumstances.
  44         function iconv( $from, $to, $string ) {
  45                 if(strcasecmp( $from, $to ) == 0) return $string;
  46                 if(strcasecmp( $from, 'utf-8' ) == 0) return utf8_decode( $string );
  47                 if(strcasecmp( $to, 'utf-8' ) == 0) return utf8_encode( $string );
  48                 return $string;
  49         }
  50 }
  51
  52 if( !function_exists('file_get_contents') ) {
  53         # Exists in PHP 4.3.0+
  54         function file_get_contents( $filename ) {
  55                 return implode( '', file( $filename ) );
  56         }
  57 }
  58
  59 if( !function_exists('is_a') ) {
  60         # Exists in PHP 4.2.0+
  61         function is_a( $object, $class_name ) {
  62                 return
  63                         (strcasecmp( get_class( $object ), $class_name ) == 0) ||
  64                          is_subclass_of( $object, $class_name );
  65         }
  66 }
  67
  68 # UTF-8 substr function based on a PHP manual comment
  69 if ( !function_exists( 'mb_substr' ) ) {
  70         function mb_substr($str,$start)
  71         {
  72                 preg_match_all("/./us", $str, $ar);
  73
  74                 if(func_num_args() >= 3) {
  75                         $end = func_get_arg(2);
  76                         return join("",array_slice($ar[0],$start,$end));
  77                 } else {
  78                         return join("",array_slice($ar[0],$start));
  79                 }
  80         }
  81 }
  82
  83 /**
  84  * html_entity_decode exists in PHP 4.3.0+ but is FATALLY BROKEN even then,
  85  * with no UTF-8 support.
  86  *
  87  * @param string $string String having html entities
  88  * @param $quote_style
  89  * @param string $charset Encoding set to use (default 'ISO-8859-1')
  90  */
  91 function do_html_entity_decode( $string, $quote_style=ENT_COMPAT, $charset='ISO-8859-1' ) {
  92         static $trans;
  93         if( !isset( $trans ) ) {
  94                 $trans = array_flip( get_html_translation_table( HTML_ENTITIES, $quote_style ) );
  95                 # Assumes $charset will always be the same through a run, and only understands
  96                 # utf-8 or default. Note - mixing latin1 named entities and unicode numbered
  97                 # ones will result in a bad link.
  98                 if( strcasecmp( 'utf-8', $charset ) == 0 ) {
  99                         $trans = array_map( 'utf8_encode', $trans );
 100                 }
 101         }
 102         return strtr( $string, $trans );
 103 }
 104
 105
 106 /**
 107  * Where as we got a random seed
 108  * @var bool $wgTotalViews
 109  */
 110 $wgRandomSeeded = false;
 111
 112 /**
 113  * Seed Mersenne Twister
 114  * Only necessary in PHP < 4.2.0
 115  *
 116  * @return bool
 117  */
 118 function wfSeedRandom() {
 119         global $wgRandomSeeded;
 120
 121         if ( ! $wgRandomSeeded && version_compare( phpversion(), '4.2.0' ) < 0 ) {
 122                 $seed = hexdec(substr(md5(microtime()),-8)) & 0x7fffffff;
 123                 mt_srand( $seed );
 124                 $wgRandomSeeded = true;
 125         }
 126 }
 127
 128 /**
 129  * Generates a URL from a URL-encoded title and a query string
 130  * Title::getLocalURL() is preferred in most cases
 131  *
 132  * @param string $a URL encoded title
 133  * @param string $q URL (default '')
 134  */
 135 function wfLocalUrl( $a, $q = '' ) {
 136         global $wgServer, $wgScript, $wgArticlePath;
 137
 138         $a = str_replace( ' ', '_', $a );
 139
 140         if ( '' == $a ) {
 141                 if( '' == $q ) {
 142                         $a = $wgScript;
 143                 } else {
 144                         $a = $wgScript.'?'.$q;
 145                 }
 146         } else if ( '' == $q ) {
 147                 $a = str_replace( '$1', $a, $wgArticlePath );
 148         } else if ($wgScript != '' ) {
 149                 $a = "{$wgScript}?title={$a}&{$q}";
 150         } else { //XXX hackish solution for toplevel wikis
 151                 $a = "/{$a}?{$q}";
 152         }
 153         return $a;
 154 }
 155
 156 /**
 157  * @todo document
 158  * @param string $a URL encoded title
 159  * @param string $q URL (default '')
 160  */
 161 function wfLocalUrlE( $a, $q = '' )
 162 {
 163         return htmlspecialchars( wfLocalUrl( $a, $q ) );
 164         # die( "Call to obsolete function wfLocalUrlE()" );
 165 }
 166
 167 /**
 168  * We want / and : to be included as literal characters in our title URLs.
 169  * %2F in the page titles seems to fatally break for some reason.
 170  *
 171  * @param string $s
 172  * @return string
 173 */
 174 function wfUrlencode ( $s ) {
 175         $s = urlencode( $s );
 176         $s = preg_replace( '/%3[Aa]/', ':', $s );
 177         $s = preg_replace( '/%2[Ff]/', '/', $s );
 178
 179         return $s;
 180 }
 181
 182 /**
 183  * Return the UTF-8 sequence for a given Unicode code point.
 184  * Currently doesn't work for values outside the Basic Multilingual Plane.
 185  *
 186  * @param string $codepoint UTF-8 code point.
 187  * @return string HTML UTF-8 Entitie such as '&#1234;'.
 188  */
 189 function wfUtf8Sequence( $codepoint ) {
 190         if($codepoint <         0x80) return chr($codepoint);
 191         if($codepoint <    0x800) return chr($codepoint >>      6 & 0x3f | 0xc0) .
 192                                                                          chr($codepoint           & 0x3f | 0x80);
 193         if($codepoint <  0x10000) return chr($codepoint >> 12 & 0x0f | 0xe0) .
 194                                                                          chr($codepoint >>      6 & 0x3f | 0x80) .
 195                                                                          chr($codepoint           & 0x3f | 0x80);
 196         if($codepoint < 0x110000) return chr($codepoint >> 18 & 0x07 | 0xf0) .
 197                                                                          chr($codepoint >> 12 & 0x3f | 0x80) .
 198                                                                          chr($codepoint >>      6 & 0x3f | 0x80) .
 199                                                                          chr($codepoint           & 0x3f | 0x80);
 200
 201         # There should be no assigned code points outside this range, but...
 202         return "&#$codepoint;";
 203 }
 204
 205 /**
 206  * Converts numeric character entities to UTF-8
 207  *
 208  * @param string $string String to convert.
 209  * @return string Converted string.
 210  */
 211 function wfMungeToUtf8( $string ) {
 212         global $wgInputEncoding; # This is debatable
 213         #$string = iconv($wgInputEncoding, "UTF-8", $string);
 214         $string = preg_replace ( '/&#([0-9]+);/e', 'wfUtf8Sequence($1)', $string );
 215         $string = preg_replace ( '/&#x([0-9a-f]+);/ie', 'wfUtf8Sequence(0x$1)', $string );
 216         # Should also do named entities here
 217         return $string;
 218 }
 219
 220 /**
 221  * Converts a single UTF-8 character into the corresponding HTML character
 222  * entity (for use with preg_replace_callback)
 223  *
 224  * @param array $matches
 225  *
 226  */
 227 function wfUtf8Entity( $matches ) {
 228         $char = $matches[0];
 229         # Find the length
 230         $z = ord( $char{0} );
 231         if ( $z & 0x80 ) {
 232                 $length = 0;
 233                 while ( $z & 0x80 ) {
 234                         $length++;
 235                         $z <<= 1;
 236                 }
 237         } else {
 238                 $length = 1;
 239         }
 240
 241         if ( $length != strlen( $char ) ) {
 242                 return '';
 243         }
 244         if ( $length == 1 ) {
 245                 return $char;
 246         }
 247
 248         # Mask off the length-determining bits and shift back to the original location
 249         $z &= 0xff;
 250         $z >>= $length;
 251
 252         # Add in the free bits from subsequent bytes
 253         for ( $i=1; $i<$length; $i++ ) {
 254                 $z <<= 6;
 255                 $z |= ord( $char{$i} ) & 0x3f;
 256         }
 257
 258         # Make entity
 259         return "&#$z;";
 260 }
 261
 262 /**
 263  * Converts all multi-byte characters in a UTF-8 string into the appropriate
 264  * character entity
 265  */
 266 function wfUtf8ToHTML($string) {
 267         return preg_replace_callback( '/[\\xc0-\\xfd][\\x80-\\xbf]*/', 'wfUtf8Entity', $string );
 268 }
 269
 270 /**
 271  * @todo document
 272  */
 273 function wfDebug( $text, $logonly = false ) {
 274         global $wgOut, $wgDebugLogFile, $wgDebugComments, $wgProfileOnly, $wgDebugRawPage;
 275
 276         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
 277         if ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' && !$wgDebugRawPage ) {
 278                 return;
 279         }
 280
 281         if ( isset( $wgOut ) && $wgDebugComments && !$logonly ) {
 282                 $wgOut->debug( $text );
 283         }
 284         if ( '' != $wgDebugLogFile && !$wgProfileOnly ) {
 285                 error_log( $text, 3, $wgDebugLogFile );
 286         }
 287 }
 288
 289 /**
 290  * Log for database errors
 291  * @param string $text Database error message.
 292  */
 293 function wfLogDBError( $text ) {
 294         global $wgDBerrorLog;
 295         if ( $wgDBerrorLog ) {
 296                 $text = date('D M j G:i:s T Y') . "\t".$text;
 297                 error_log( $text, 3, $wgDBerrorLog );
 298         }
 299 }
 300
 301 /**
 302  * @todo document
 303  */
 304 function logProfilingData() {
 305         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
 306         global $wgProfiling, $wgProfileStack, $wgProfileLimit, $wgUser;
 307         $now = wfTime();
 308
 309         list( $usec, $sec ) = explode( ' ', $wgRequestTime );
 310         $start = (float)$sec + (float)$usec;
 311         $elapsed = $now - $start;
 312         if ( $wgProfiling ) {
 313                 $prof = wfGetProfilingOutput( $start, $elapsed );
 314                 $forward = '';
 315                 if( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) )
 316                         $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
 317                 if( !empty( $_SERVER['HTTP_CLIENT_IP'] ) )
 318                         $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
 319                 if( !empty( $_SERVER['HTTP_FROM'] ) )
 320                         $forward .= ' from ' . $_SERVER['HTTP_FROM'];
 321                 if( $forward )
 322                         $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
 323                 if($wgUser->getId() == 0)
 324                         $forward .= ' anon';
 325                 $log = sprintf( "%s\t%04.3f\t%s\n",
 326                   gmdate( 'YmdHis' ), $elapsed,
 327                   urldecode( $_SERVER['REQUEST_URI'] . $forward ) );
 328                 if ( '' != $wgDebugLogFile && ( $wgRequest->getVal('action') != 'raw' || $wgDebugRawPage ) ) {
 329                         error_log( $log . $prof, 3, $wgDebugLogFile );
 330                 }
 331         }
 332 }
 333
 334 /**
 335  * Check if the wiki read-only lock file is present. This can be used to lock
 336  * off editing functions, but doesn't guarantee that the database will not be
 337  * modified.
 338  * @return bool
 339  */
 340 function wfReadOnly() {
 341         global $wgReadOnlyFile;
 342
 343         if ( '' == $wgReadOnlyFile ) {
 344                 return false;
 345         }
 346         return is_file( $wgReadOnlyFile );
 347 }
 348
 349 /**
 350  * Keys strings for replacement
 351  * @global array $wgReplacementKeys
 352  */
 353 $wgReplacementKeys = array( '$1', '$2', '$3', '$4', '$5', '$6', '$7', '$8', '$9' );
 354
 355 /**
 356  * Get a message from anywhere
 357  */
 358 function wfMsg( $key, $convert=true ) {
 359         global $wgRequest;
 360         if ( $wgRequest->getVal( 'debugmsg' ) ) {
 361                 if ( $key == 'linktrail' /* a special case where we want to return something specific */ )
 362                         return "/^()(.*)$/sD";
 363                 else
 364                         return $key;
 365         }
 366         $args = func_get_args();
 367         if ( count( $args ) ) {
 368                 array_shift( $args );
 369         }
 370         return wfMsgReal( $key, $args, true, $convert );
 371 }
 372
 373 /**
 374  * Get a message from the language file
 375  */
 376 function wfMsgNoDB( $key, $convert=true ) {
 377         $args = func_get_args();
 378         if ( count( $args ) ) {
 379                 array_shift( $args );
 380         }
 381         return wfMsgReal( $key, $args, false, $convert );
 382 }
 383
 384 /**
 385  * Really get a message
 386  */
 387 function wfMsgReal( $key, $args, $useDB, $convert=true ) {
 388         global $wgReplacementKeys, $wgMessageCache, $wgLang;
 389
 390         $fname = 'wfMsg';
 391         wfProfileIn( $fname );
 392         if ( $wgMessageCache ) {
 393                 $message = $wgMessageCache->get( $key, $useDB );
 394         } elseif ( $wgLang ) {
 395                 $message = $wgLang->getMessage( $key );
 396         } else {
 397                 wfDebug( "No language object when getting $key\n" );
 398                 $message = "&lt;$key&gt;";
 399         }
 400
 401         if ( $convert ) {
 402                 $message = $wgLang->convert($message);
 403         }
 404
 405         # Replace arguments
 406         if( count( $args ) ) {
 407                 $message = str_replace( $wgReplacementKeys, $args, $message );
 408         }
 409         wfProfileOut( $fname );
 410         return $message;
 411 }
 412
 413
 414
 415 /**
 416  * Just like exit() but makes a note of it.
 417  * Commits open transactions except if the error parameter is set
 418  */
 419 function wfAbruptExit( $error = false ){
 420         global $wgLoadBalancer;
 421         static $called = false;
 422         if ( $called ){
 423                 exit();
 424         }
 425         $called = true;
 426
 427         if( function_exists( 'debug_backtrace' ) ){ // PHP >= 4.3
 428                 $bt = debug_backtrace();
 429                 for($i = 0; $i < count($bt) ; $i++){
 430                         $file = $bt[$i]['file'];
 431                         $line = $bt[$i]['line'];
 432                         wfDebug("WARNING: Abrupt exit in $file at line $line\n");
 433                 }
 434         } else {
 435                 wfDebug('WARNING: Abrupt exit\n');
 436         }
 437         if ( !$error ) {
 438                 $wgLoadBalancer->closeAll();
 439         }
 440         exit();
 441 }
 442
 443 /**
 444  * @todo document
 445  */
 446 function wfErrorExit() {
 447         wfAbruptExit( true );
 448 }
 449
 450 /**
 451  * Die with a backtrace
 452  * This is meant as a debugging aid to track down where bad data comes from.
 453  * Shouldn't be used in production code except maybe in "shouldn't happen" areas.
 454  *
 455  * @param string $msg Message shown when dieing.
 456  */
 457 function wfDebugDieBacktrace( $msg = '' ) {
 458         global $wgCommandLineMode;
 459
 460         if ( function_exists( 'debug_backtrace' ) ) {
 461                 if ( $wgCommandLineMode ) {
 462                         $msg .= "\nBacktrace:\n";
 463                 } else {
 464                         $msg .= "\n<p>Backtrace:</p>\n<ul>\n";
 465                 }
 466                 $backtrace = debug_backtrace();
 467                 foreach( $backtrace as $call ) {
 468                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
 469                         $file = $f[count($f)-1];
 470                         if ( $wgCommandLineMode ) {
 471                                 $msg .= "$file line {$call['line']} calls ";
 472                         } else {
 473                                 $msg .= '<li>' . $file . ' line ' . $call['line'] . ' calls ';
 474                         }
 475                         if( !empty( $call['class'] ) ) $msg .= $call['class'] . '::';
 476                         $msg .= $call['function'] . '()';
 477
 478                         if ( $wgCommandLineMode ) {
 479                                 $msg .= "\n";
 480                         } else {
 481                                 $msg .= "</li>\n";
 482                         }
 483                 }
 484          }
 485          die( $msg );
 486 }
 487
 488
 489 /* Some generic result counters, pulled out of SearchEngine */
 490
 491
 492 /**
 493  * @todo document
 494  */
 495 function wfShowingResults( $offset, $limit ) {
 496         global $wgLang;
 497         return wfMsg( 'showingresults', $wgLang->formatNum( $limit ), $wgLang->formatNum( $offset+1 ) );
 498 }
 499
 500 /**
 501  * @todo document
 502  */
 503 function wfShowingResultsNum( $offset, $limit, $num ) {
 504         global $wgLang;
 505         return wfMsg( 'showingresultsnum', $wgLang->formatNum( $limit ), $wgLang->formatNum( $offset+1 ), $wgLang->formatNum( $num ) );
 506 }
 507
 508 /**
 509  * @todo document
 510  */
 511 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
 512         global $wgUser, $wgLang;
 513         $fmtLimit = $wgLang->formatNum( $limit );
 514         $prev = wfMsg( 'prevn', $fmtLimit );
 515         $next = wfMsg( 'nextn', $fmtLimit );
 516         $link = wfUrlencode( $link );
 517
 518         $sk = $wgUser->getSkin();
 519         if ( 0 != $offset ) {
 520                 $po = $offset - $limit;
 521                 if ( $po < 0 ) { $po = 0; }
 522                 $q = "limit={$limit}&offset={$po}";
 523                 if ( '' != $query ) { $q .= '&'.$query; }
 524                 $plink = '<a href="' . wfLocalUrlE( $link, $q ) . "\">{$prev}</a>";
 525         } else { $plink = $prev; }
 526
 527         $no = $offset + $limit;
 528         $q = 'limit='.$limit.'&offset='.$no;
 529         if ( '' != $query ) { $q .= '&'.$query; }
 530
 531         if ( $atend ) {
 532                 $nlink = $next;
 533         } else {
 534                 $nlink = '<a href="' . wfLocalUrlE( $link, $q ) . "\">{$next}</a>";
 535         }
 536         $nums = wfNumLink( $offset, 20, $link , $query ) . ' | ' .
 537           wfNumLink( $offset, 50, $link, $query ) . ' | ' .
 538           wfNumLink( $offset, 100, $link, $query ) . ' | ' .
 539           wfNumLink( $offset, 250, $link, $query ) . ' | ' .
 540           wfNumLink( $offset, 500, $link, $query );
 541
 542         return wfMsg( 'viewprevnext', $plink, $nlink, $nums );
 543 }
 544
 545 /**
 546  * @todo document
 547  */
 548 function wfNumLink( $offset, $limit, $link, $query = '' ) {
 549         global $wgUser, $wgLang;
 550         if ( '' == $query ) { $q = ''; }
 551         else { $q = $query.'&'; }
 552         $q .= 'limit='.$limit.'&offset='.$offset;
 553
 554         $fmtLimit = $wgLang->formatNum( $limit );
 555         $s = '<a href="' . wfLocalUrlE( $link, $q ) . "\">{$fmtLimit}</a>";
 556         return $s;
 557 }
 558
 559 /**
 560  * @todo document
 561  * @todo FIXME: we may want to blacklist some broken browsers
 562  *
 563  * @return bool Whereas client accept gzip compression
 564  */
 565 function wfClientAcceptsGzip() {
 566         global $wgUseGzip;
 567         if( $wgUseGzip ) {
 568                 # FIXME: we may want to blacklist some broken browsers
 569                 if( preg_match(
 570                         '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
 571                         $_SERVER['HTTP_ACCEPT_ENCODING'],
 572                         $m ) ) {
 573                         if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) return false;
 574                         wfDebug( " accepts gzip\n" );
 575                         return true;
 576                 }
 577         }
 578         return false;
 579 }
 580
 581 /**
 582  * Yay, more global functions!
 583  */
 584 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
 585         global $wgRequest;
 586         return $wgRequest->getLimitOffset( $deflimit, $optionname );
 587 }
 588
 589 /**
 590  * Escapes the given text so that it may be output using addWikiText()
 591  * without any linking, formatting, etc. making its way through. This
 592  * is achieved by substituting certain characters with HTML entities.
 593  * As required by the callers, <nowiki> is not used. It currently does
 594  * not filter out characters which have special meaning only at the
 595  * start of a line, such as "*".
 596  *
 597  * @param string $text Text to be escaped
 598  */
 599 function wfEscapeWikiText( $text ) {
 600         $text = str_replace(
 601                 array( '[',             '|',      "'",     'ISBN '        , '://'         , "\n=", '{{' ),
 602                 array( '&#91;', '&#124;', '&#39;', 'ISBN&#32;', '&#58;//' , "\n&#61;", '&#123;&#123;' ),
 603                 htmlspecialchars($text) );
 604         return $text;
 605 }
 606
 607 /**
 608  * @todo document
 609  */
 610 function wfQuotedPrintable( $string, $charset = '' ) {
 611         # Probably incomplete; see RFC 2045
 612         if( empty( $charset ) ) {
 613                 global $wgInputEncoding;
 614                 $charset = $wgInputEncoding;
 615         }
 616         $charset = strtoupper( $charset );
 617         $charset = str_replace( 'ISO-8859', 'ISO8859', $charset ); // ?
 618
 619         $illegal = '\x00-\x08\x0b\x0c\x0e-\x1f\x7f-\xff=';
 620         $replace = $illegal . '\t ?_';
 621         if( !preg_match( "/[$illegal]/", $string ) ) return $string;
 622         $out = "=?$charset?Q?";
 623         $out .= preg_replace( "/([$replace])/e", 'sprintf("=%02X",ord("$1"))', $string );
 624         $out .= '?=';
 625         return $out;
 626 }
 627
 628 /**
 629  * @todo document
 630  * @return float
 631  */
 632 function wfTime() {
 633         $st = explode( ' ', microtime() );
 634         return (float)$st[0] + (float)$st[1];
 635 }
 636
 637 /**
 638  * Changes the first character to an HTML entity
 639  */
 640 function wfHtmlEscapeFirst( $text ) {
 641         $ord = ord($text);
 642         $newText = substr($text, 1);
 643         return "&#$ord;$newText";
 644 }
 645
 646 /**
 647  * Sets dest to source and returns the original value of dest
 648  * If source is NULL, it just returns the value, it doesn't set the variable
 649  */
 650 function wfSetVar( &$dest, $source ) {
 651         $temp = $dest;
 652         if ( !is_null( $source ) ) {
 653                 $dest = $source;
 654         }
 655         return $temp;
 656 }
 657
 658 /**
 659  * As for wfSetVar except setting a bit
 660  */
 661 function wfSetBit( &$dest, $bit, $state = true ) {
 662         $temp = (bool)($dest & $bit );
 663         if ( !is_null( $state ) ) {
 664                 if ( $state ) {
 665                         $dest |= $bit;
 666                 } else {
 667                         $dest &= ~$bit;
 668                 }
 669         }
 670         return $temp;
 671 }
 672
 673 /**
 674  * This function takes two arrays as input, and returns a CGI-style string, e.g.
 675  * "days=7&limit=100". Options in the first array override options in the second.
 676  * Options set to "" will not be output.
 677  */
 678 function wfArrayToCGI( $array1, $array2 = NULL )
 679 {
 680         if ( !is_null( $array2 ) ) {
 681                 $array1 = $array1 + $array2;
 682         }
 683
 684         $cgi = '';
 685         foreach ( $array1 as $key => $value ) {
 686                 if ( '' !== $value ) {
 687                         if ( '' != $cgi ) {
 688                                 $cgi .= '&';
 689                         }
 690                         $cgi .= $key.'='.$value;
 691                 }
 692         }
 693         return $cgi;
 694 }
 695
 696 /**
 697  * This is obsolete, use SquidUpdate::purge()
 698  * @deprecated
 699  */
 700 function wfPurgeSquidServers ($urlArr) {
 701         SquidUpdate::purge( $urlArr );
 702 }
 703
 704 /**
 705  * Windows-compatible version of escapeshellarg()
 706  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
 707  * function puts single quotes in regardless of OS
 708  */
 709 function wfEscapeShellArg( ) {
 710         $args = func_get_args();
 711         $first = true;
 712         $retVal = '';
 713         foreach ( $args as $arg ) {
 714                 if ( !$first ) {
 715                         $retVal .= ' ';
 716                 } else {
 717                         $first = false;
 718                 }
 719
 720                 if ( wfIsWindows() ) {
 721                         $retVal .= '"' . str_replace( '"','\"', $arg ) . '"';
 722                 } else {
 723                         $retVal .= escapeshellarg( $arg );
 724                 }
 725         }
 726         return $retVal;
 727 }
 728
 729 /**
 730  * wfMerge attempts to merge differences between three texts.
 731  * Returns true for a clean merge and false for failure or a conflict.
 732  */
 733 function wfMerge( $old, $mine, $yours, &$result ){
 734         global $wgDiff3;
 735
 736         # This check may also protect against code injection in
 737         # case of broken installations.
 738         if(! file_exists( $wgDiff3 ) ){
 739                 return false;
 740         }
 741
 742         # Make temporary files
 743         $td = '/tmp/';
 744         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
 745         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
 746         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
 747
 748         fwrite( $oldtextFile, $old ); fclose( $oldtextFile );
 749         fwrite( $mytextFile, $mine ); fclose( $mytextFile );
 750         fwrite( $yourtextFile, $yours ); fclose( $yourtextFile );
 751
 752         # Check for a conflict
 753         $cmd = wfEscapeShellArg( $wgDiff3 ) . ' -a --overlap-only ' .
 754           wfEscapeShellArg( $mytextName ) . ' ' .
 755           wfEscapeShellArg( $oldtextName ) . ' ' .
 756           wfEscapeShellArg( $yourtextName );
 757         $handle = popen( $cmd, 'r' );
 758
 759         if( fgets( $handle ) ){
 760                 $conflict = true;
 761         } else {
 762                 $conflict = false;
 763         }
 764         pclose( $handle );
 765
 766         # Merge differences
 767         $cmd = wfEscapeShellArg( $wgDiff3 ) . ' -a -e --merge ' .
 768           wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
 769         $handle = popen( $cmd, 'r' );
 770         $result = '';
 771         do {
 772                 $data = fread( $handle, 8192 );
 773                 if ( strlen( $data ) == 0 ) {
 774                         break;
 775                 }
 776                 $result .= $data;
 777         } while ( true );
 778         pclose( $handle );
 779         unlink( $mytextName ); unlink( $oldtextName ); unlink( $yourtextName );
 780         return ! $conflict;
 781 }
 782
 783 /**
 784  * @todo document
 785  */
 786 function wfVarDump( $var ) {
 787         global $wgOut;
 788         $s = str_replace("\n","<br>\n", var_export( $var, true ) . "\n");
 789         if ( headers_sent() || !@is_object( $wgOut ) ) {
 790                 print $s;
 791         } else {
 792                 $wgOut->addHTML( $s );
 793         }
 794 }
 795
 796 /**
 797  * Provide a simple HTTP error.
 798  */
 799 function wfHttpError( $code, $label, $desc ) {
 800         global $wgOut;
 801         $wgOut->disable();
 802         header( "HTTP/1.0 $code $label" );
 803         header( "Status: $code $label" );
 804         $wgOut->sendCacheControl();
 805
 806         # Don't send content if it's a HEAD request.
 807         if( $_SERVER['REQUEST_METHOD'] == 'HEAD' ) {
 808                 header( 'Content-type: text/plain' );
 809                 print "$desc\n";
 810         }
 811 }
 812
 813 /**
 814  * Converts an Accept-* header into an array mapping string values to quality
 815  * factors
 816  */
 817 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
 818         # No arg means accept anything (per HTTP spec)
 819         if( !$accept ) {
 820                 return array( $def => 1 );
 821         }
 822
 823         $prefs = array();
 824
 825         $parts = explode( ',', $accept );
 826
 827         foreach( $parts as $part ) {
 828                 # FIXME: doesn't deal with params like 'text/html; level=1'
 829                 @list( $value, $qpart ) = explode( ';', $part );
 830                 if( !isset( $qpart ) ) {
 831                         $prefs[$value] = 1;
 832                 } elseif( preg_match( '/q\s*=\s*(\d*\.\d+)/', $qpart, $match ) ) {
 833                         $prefs[$value] = $match[1];
 834                 }
 835         }
 836
 837         return $prefs;
 838 }
 839
 840 /**
 841  * @todo document
 842  * @private
 843  */
 844 function mimeTypeMatch( $type, $avail ) {
 845         if( array_key_exists($type, $avail) ) {
 846                 return $type;
 847         } else {
 848                 $parts = explode( '/', $type );
 849                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
 850                         return $parts[0] . '/*';
 851                 } elseif( array_key_exists( '*/*', $avail ) ) {
 852                         return '*/*';
 853                 } else {
 854                         return NULL;
 855                 }
 856         }
 857 }
 858
 859 /**
 860  * @todo FIXME: doesn't handle params like 'text/plain; charset=UTF-8'
 861  * XXX: generalize to negotiate other stuff
 862  */
 863 function wfNegotiateType( $cprefs, $sprefs ) {
 864         $combine = array();
 865
 866         foreach( array_keys($sprefs) as $type ) {
 867                 $parts = explode( '/', $type );
 868                 if( $parts[1] != '*' ) {
 869                         $ckey = mimeTypeMatch( $type, $cprefs );
 870                         if( $ckey ) {
 871                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
 872                         }
 873                 }
 874         }
 875
 876         foreach( array_keys( $cprefs ) as $type ) {
 877                 $parts = explode( '/', $type );
 878                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
 879                         $skey = mimeTypeMatch( $type, $sprefs );
 880                         if( $skey ) {
 881                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
 882                         }
 883                 }
 884         }
 885
 886         $bestq = 0;
 887         $besttype = NULL;
 888
 889         foreach( array_keys( $combine ) as $type ) {
 890                 if( $combine[$type] > $bestq ) {
 891                         $besttype = $type;
 892                         $bestq = $combine[$type];
 893                 }
 894         }
 895
 896         return $besttype;
 897 }
 898
 899 /**
 900  * Array lookup
 901  * Returns an array where the values in the first array are replaced by the
 902  * values in the second array with the corresponding keys
 903  *
 904  * @return array
 905  */
 906 function wfArrayLookup( $a, $b ) {
 907         return array_flip( array_intersect( array_flip( $a ), array_keys( $b ) ) );
 908 }
 909
 910
 911 /**
 912  * Ideally we'd be using actual time fields in the db
 913  * @todo fixme
 914  */
 915 function wfTimestamp2Unix( $ts ) {
 916         return gmmktime( ( (int)substr( $ts, 8, 2) ),
 917                   (int)substr( $ts, 10, 2 ), (int)substr( $ts, 12, 2 ),
 918                   (int)substr( $ts, 4, 2 ), (int)substr( $ts, 6, 2 ),
 919                   (int)substr( $ts, 0, 4 ) );
 920 }
 921
 922 /**
 923  * @todo document
 924  */
 925 function wfUnix2Timestamp( $unixtime ) {
 926         return gmdate( 'YmdHis', $unixtime );
 927 }
 928
 929 /**
 930  * @todo document
 931  */
 932 function wfTimestampNow() {
 933         # return NOW
 934         return gmdate( 'YmdHis' );
 935 }
 936
 937 /**
 938  * Sorting hack for MySQL 3, which doesn't use index sorts for DESC
 939  */
 940 function wfInvertTimestamp( $ts ) {
 941         return strtr(
 942                 $ts,
 943                 '0123456789',
 944                 '9876543210'
 945         );
 946 }
 947
 948 /**
 949  * Reference-counted warning suppression
 950  */
 951 function wfSuppressWarnings( $end = false ) {
 952         static $suppressCount = 0;
 953         static $originalLevel = false;
 954
 955         if ( $end ) {
 956                 if ( $suppressCount ) {
 957                         $suppressCount --;
 958                         if ( !$suppressCount ) {
 959                                 error_reporting( $originalLevel );
 960                         }
 961                 }
 962         } else {
 963                 if ( !$suppressCount ) {
 964                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE ) );
 965                 }
 966                 $suppressCount++;
 967         }
 968 }
 969
 970 /**
 971  * Restore error level to previous value
 972  */
 973 function wfRestoreWarnings() {
 974         wfSuppressWarnings( true );
 975 }
 976
 977 # Autodetect, convert and provide timestamps of various types
 978
 979 /** Standard unix timestamp (number of seconds since 1 Jan 1970) */
 980 define('TS_UNIX',0);
 981 /** MediaWiki concatenated string timestamp (yyyymmddhhmmss) */
 982 define('TS_MW',1);
 983 /** Standard database timestamp (yyyy-mm-dd hh:mm:ss) */
 984 define('TS_DB',2);
 985
 986 /**
 987  * @todo document
 988  */
 989 function wfTimestamp($outputtype=TS_UNIX,$ts=0) {
 990         if (preg_match("/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/",$ts,$da)) {
 991                 # TS_DB
 992                 $uts=gmmktime((int)$da[4],(int)$da[5],(int)$da[6],
 993                             (int)$da[2],(int)$da[3],(int)$da[1]);
 994         } elseif (preg_match("/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/",$ts,$da)) {
 995                 # TS_MW
 996                 $uts=gmmktime((int)$da[4],(int)$da[5],(int)$da[6],
 997                             (int)$da[2],(int)$da[3],(int)$da[1]);
 998         } elseif (preg_match("/^(\d{1,13})$/",$ts,$datearray)) {
 999                 # TS_UNIX
1000                 $uts=$ts;
1001         }
1002
1003         if ($ts==0)
1004                 $uts=time();
1005         switch($outputtype) {
1006         case TS_UNIX:
1007                 return $uts;
1008                 break;
1009         case TS_MW:
1010                 return gmdate( 'YmdHis', $uts );
1011                 break;
1012         case TS_DB:
1013                 return gmdate( 'Y-m-d H:i:s', $uts );
1014                 break;
1015         default:
1016                 return;
1017         }
1018 }
1019
1020 /**
1021  * Check where as the operating system is Windows
1022  *
1023  * @todo document
1024  * @return bool True if it's windows, False otherwise.
1025  */
1026 function wfIsWindows() {
1027         if (substr(php_uname(), 0, 7) == 'Windows') {
1028                 return true;
1029         } else {
1030                 return false;
1031         }
1032 }
1033
1034 ?>