includes/GlobalFunctions.php

   1 <?php
   2
   3 if ( !defined( 'MEDIAWIKI' ) ) {
   4         die( "This file is part of MediaWiki, it is not a valid entry point" );
   5 }
   6
   7 /**
   8  * Global functions used everywhere
   9  */
  10
  11 require_once dirname(__FILE__) . '/LogPage.php';
  12 require_once dirname(__FILE__) . '/normal/UtfNormalUtil.php';
  13 require_once dirname(__FILE__) . '/XmlFunctions.php';
  14
  15 // Hide compatibility functions from Doxygen
  16 /// @cond
  17
  18 /**
  19  * Compatibility functions
  20  *
  21  * We more or less support PHP 5.0.x and up.
  22  * Re-implementations of newer functions or functions in non-standard
  23  * PHP extensions may be included here.
  24  */
  25 if( !function_exists('iconv') ) {
  26         # iconv support is not in the default configuration and so may not be present.
  27         # Assume will only ever use utf-8 and iso-8859-1.
  28         # This will *not* work in all circumstances.
  29         function iconv( $from, $to, $string ) {
  30                 if(strcasecmp( $from, $to ) == 0) return $string;
  31                 if(strcasecmp( $from, 'utf-8' ) == 0) return utf8_decode( $string );
  32                 if(strcasecmp( $to, 'utf-8' ) == 0) return utf8_encode( $string );
  33                 return $string;
  34         }
  35 }
  36
  37 # UTF-8 substr function based on a PHP manual comment
  38 if ( !function_exists( 'mb_substr' ) ) {
  39         function mb_substr( $str, $start ) {
  40                 $ar = array();
  41                 preg_match_all( '/./us', $str, $ar );
  42
  43                 if( func_num_args() >= 3 ) {
  44                         $end = func_get_arg( 2 );
  45                         return join( '', array_slice( $ar[0], $start, $end ) );
  46                 } else {
  47                         return join( '', array_slice( $ar[0], $start ) );
  48                 }
  49         }
  50 }
  51
  52 if ( !function_exists( 'mb_strlen' ) ) {
  53         /**
  54          * Fallback implementation of mb_strlen, hardcoded to UTF-8.
  55          * @param string $str
  56          * @param string $enc optional encoding; ignored
  57          * @return int
  58          */
  59         function mb_strlen( $str, $enc="" ) {
  60                 $counts = count_chars( $str );
  61                 $total = 0;
  62
  63                 // Count ASCII bytes
  64                 for( $i = 0; $i < 0x80; $i++ ) {
  65                         $total += $counts[$i];
  66                 }
  67
  68                 // Count multibyte sequence heads
  69                 for( $i = 0xc0; $i < 0xff; $i++ ) {
  70                         $total += $counts[$i];
  71                 }
  72                 return $total;
  73         }
  74 }
  75
  76 if ( !function_exists( 'array_diff_key' ) ) {
  77         /**
  78          * Exists in PHP 5.1.0+
  79          * Not quite compatible, two-argument version only
  80          * Null values will cause problems due to this use of isset()
  81          */
  82         function array_diff_key( $left, $right ) {
  83                 $result = $left;
  84                 foreach ( $left as $key => $unused ) {
  85                         if ( isset( $right[$key] ) ) {
  86                                 unset( $result[$key] );
  87                         }
  88                 }
  89                 return $result;
  90         }
  91 }
  92
  93 /// @endcond
  94
  95
  96 /**
  97  * Like array_diff( $a, $b ) except that it works with two-dimensional arrays.
  98  */
  99 function wfArrayDiff2( $a, $b ) {
 100         return array_udiff( $a, $b, 'wfArrayDiff2_cmp' );
 101 }
 102 function wfArrayDiff2_cmp( $a, $b ) {
 103         if ( !is_array( $a ) ) {
 104                 return strcmp( $a, $b );
 105         } elseif ( count( $a ) !== count( $b ) ) {
 106                 return count( $a ) < count( $b ) ? -1 : 1;
 107         } else {
 108                 reset( $a );
 109                 reset( $b );
 110                 while( ( list( $keyA, $valueA ) = each( $a ) ) && ( list( $keyB, $valueB ) = each( $b ) ) ) {
 111                         $cmp = strcmp( $valueA, $valueB );
 112                         if ( $cmp !== 0 ) {
 113                                 return $cmp;
 114                         }
 115                 }
 116                 return 0;
 117         }
 118 }
 119
 120 /**
 121  * Wrapper for clone(), for compatibility with PHP4-friendly extensions.
 122  * PHP 5 won't let you declare a 'clone' function, even conditionally,
 123  * so it has to be a wrapper with a different name.
 124  */
 125 function wfClone( $object ) {
 126         return clone( $object );
 127 }
 128
 129 /**
 130  * Seed Mersenne Twister
 131  * No-op for compatibility; only necessary in PHP < 4.2.0
 132  */
 133 function wfSeedRandom() {
 134         /* No-op */
 135 }
 136
 137 /**
 138  * Get a random decimal value between 0 and 1, in a way
 139  * not likely to give duplicate values for any realistic
 140  * number of articles.
 141  *
 142  * @return string
 143  */
 144 function wfRandom() {
 145         # The maximum random value is "only" 2^31-1, so get two random
 146         # values to reduce the chance of dupes
 147         $max = mt_getrandmax() + 1;
 148         $rand = number_format( (mt_rand() * $max + mt_rand())
 149                 / $max / $max, 12, '.', '' );
 150         return $rand;
 151 }
 152
 153 /**
 154  * We want some things to be included as literal characters in our title URLs
 155  * for prettiness, which urlencode encodes by default.  According to RFC 1738,
 156  * all of the following should be safe:
 157  *
 158  * ;:@&=$-_.+!*'(),
 159  *
 160  * But + is not safe because it's used to indicate a space; &= are only safe in
 161  * paths and not in queries (and we don't distinguish here); ' seems kind of
 162  * scary; and urlencode() doesn't touch -_. to begin with.  Plus, although /
 163  * is reserved, we don't care.  So the list we unescape is:
 164  *
 165  * ;:@$!*(),/
 166  *
 167  * %2F in the page titles seems to fatally break for some reason.
 168  *
 169  * @param $s String:
 170  * @return string
 171 */
 172 function wfUrlencode( $s ) {
 173         $s = urlencode( $s );
 174         $s = str_ireplace(
 175                 array( '%3B','%3A','%40','%24','%21','%2A','%28','%29','%2C','%2F' ),
 176                 array(   ';',  ':',  '@',  '$',  '!',  '*',  '(',  ')',  ',',  '/' ),
 177                 $s
 178         );
 179
 180         return $s;
 181 }
 182
 183 /**
 184  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
 185  * In normal operation this is a NOP.
 186  *
 187  * Controlling globals:
 188  * $wgDebugLogFile - points to the log file
 189  * $wgProfileOnly - if set, normal debug messages will not be recorded.
 190  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
 191  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
 192  *
 193  * @param $text String
 194  * @param $logonly Bool: set true to avoid appearing in HTML when $wgDebugComments is set
 195  */
 196 function wfDebug( $text, $logonly = false ) {
 197         global $wgOut, $wgDebugLogFile, $wgDebugComments, $wgProfileOnly, $wgDebugRawPage;
 198         static $recursion = 0;
 199
 200         static $cache = array(); // Cache of unoutputted messages
 201
 202         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
 203         if ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' && !$wgDebugRawPage ) {
 204                 return;
 205         }
 206
 207         if ( $wgDebugComments && !$logonly ) {
 208                 $cache[] = $text;
 209
 210                 if ( !isset( $wgOut ) ) {
 211                         return;
 212                 }
 213                 if ( !StubObject::isRealObject( $wgOut ) ) {
 214                         if ( $recursion ) {
 215                                 return;
 216                         }
 217                         $recursion++;
 218                         $wgOut->_unstub();
 219                         $recursion--;
 220                 }
 221
 222                 // add the message and possible cached ones to the output
 223                 array_map( array( $wgOut, 'debug' ), $cache );
 224                 $cache = array();
 225         }
 226         if ( '' != $wgDebugLogFile && !$wgProfileOnly ) {
 227                 # Strip unprintables; they can switch terminal modes when binary data
 228                 # gets dumped, which is pretty annoying.
 229                 $text = preg_replace( '![\x00-\x08\x0b\x0c\x0e-\x1f]!', ' ', $text );
 230                 wfErrorLog( $text, $wgDebugLogFile );
 231         }
 232 }
 233
 234 /**
 235  * Send a line giving PHP memory usage.
 236  * @param $exact Bool : print exact values instead of kilobytes (default: false)
 237  */
 238 function wfDebugMem( $exact = false ) {
 239         $mem = memory_get_usage();
 240         if( !$exact ) {
 241                 $mem = floor( $mem / 1024 ) . ' kilobytes';
 242         } else {
 243                 $mem .= ' bytes';
 244         }
 245         wfDebug( "Memory usage: $mem\n" );
 246 }
 247
 248 /**
 249  * Send a line to a supplementary debug log file, if configured, or main debug log if not.
 250  * $wgDebugLogGroups[$logGroup] should be set to a filename to send to a separate log.
 251  *
 252  * @param $logGroup String
 253  * @param $text String
 254  * @param $public Bool: whether to log the event in the public log if no private
 255  *                     log file is specified, (default true)
 256  */
 257 function wfDebugLog( $logGroup, $text, $public = true ) {
 258         global $wgDebugLogGroups, $wgShowHostnames;
 259         if( $text{strlen( $text ) - 1} != "\n" ) $text .= "\n";
 260         if( isset( $wgDebugLogGroups[$logGroup] ) ) {
 261                 $time = wfTimestamp( TS_DB );
 262                 $wiki = wfWikiID();
 263                 if ( $wgShowHostnames ) {
 264                         $host = wfHostname();
 265                 } else {
 266                         $host = '';
 267                 }
 268                 wfErrorLog( "$time $host $wiki: $text", $wgDebugLogGroups[$logGroup] );
 269         } else if ( $public === true ) {
 270                 wfDebug( $text, true );
 271         }
 272 }
 273
 274 /**
 275  * Log for database errors
 276  * @param $text String: database error message.
 277  */
 278 function wfLogDBError( $text ) {
 279         global $wgDBerrorLog, $wgDBname;
 280         if ( $wgDBerrorLog ) {
 281                 $host = trim(`hostname`);
 282                 $text = date('D M j G:i:s T Y') . "\t$host\t$wgDBname\t$text";
 283                 wfErrorLog( $text, $wgDBerrorLog );
 284         }
 285 }
 286
 287 /**
 288  * Log to a file without getting "file size exceeded" signals.
 289  *
 290  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
 291  * send lines to the specified port, prefixed by the specified prefix and a space.
 292  */
 293 function wfErrorLog( $text, $file ) {
 294         if ( substr( $file, 0, 4 ) == 'udp:' ) {
 295                 if ( preg_match( '!^(tcp|udp):(?://)?\[([0-9a-fA-F:]+)\]:(\d+)(?:/(.*))?$!', $file, $m ) ) {
 296                         // IPv6 bracketed host
 297                         $protocol = $m[1];
 298                         $host = $m[2];
 299                         $port = $m[3];
 300                         $prefix = isset( $m[4] ) ? $m[4] : false;
 301                 } elseif ( preg_match( '!^(tcp|udp):(?://)?([a-zA-Z0-9-]+):(\d+)(?:/(.*))?$!', $file, $m ) ) {
 302                         $protocol = $m[1];
 303                         $host = $m[2];
 304                         $port = $m[3];
 305                         $prefix = isset( $m[4] ) ? $m[4] : false;
 306                 } else {
 307                         throw new MWException( __METHOD__.": Invalid UDP specification" );
 308                 }
 309                 // Clean it up for the multiplexer
 310                 if ( strval( $prefix ) !== '' ) {
 311                         $text = preg_replace( '/^/m', $prefix . ' ', $text );
 312                         if ( substr( $text, -1 ) != "\n" ) {
 313                                 $text .= "\n";
 314                         }
 315                 }
 316
 317                 $sock = fsockopen( "$protocol://$host", $port );
 318                 if ( !$sock ) {
 319                         return;
 320                 }
 321                 fwrite( $sock, $text );
 322                 fclose( $sock );
 323         } else {
 324                 wfSuppressWarnings();
 325                 $exists = file_exists( $file );
 326                 $size = $exists ? filesize( $file ) : false;
 327                 if ( !$exists || ( $size !== false && $size + strlen( $text ) < 0x7fffffff ) ) {
 328                         error_log( $text, 3, $file );
 329                 }
 330                 wfRestoreWarnings();
 331         }
 332 }
 333
 334 /**
 335  * @todo document
 336  */
 337 function wfLogProfilingData() {
 338         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
 339         global $wgProfiler, $wgUser;
 340         if ( !isset( $wgProfiler ) )
 341                 return;
 342
 343         $now = wfTime();
 344         $elapsed = $now - $wgRequestTime;
 345         $prof = wfGetProfilingOutput( $wgRequestTime, $elapsed );
 346         $forward = '';
 347         if( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) )
 348                 $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
 349         if( !empty( $_SERVER['HTTP_CLIENT_IP'] ) )
 350                 $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
 351         if( !empty( $_SERVER['HTTP_FROM'] ) )
 352                 $forward .= ' from ' . $_SERVER['HTTP_FROM'];
 353         if( $forward )
 354                 $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
 355         // Don't unstub $wgUser at this late stage just for statistics purposes
 356         if( StubObject::isRealObject($wgUser) && $wgUser->isAnon() )
 357                 $forward .= ' anon';
 358         $log = sprintf( "%s\t%04.3f\t%s\n",
 359           gmdate( 'YmdHis' ), $elapsed,
 360           urldecode( $wgRequest->getRequestURL() . $forward ) );
 361         if ( '' != $wgDebugLogFile && ( $wgRequest->getVal('action') != 'raw' || $wgDebugRawPage ) ) {
 362                 wfErrorLog( $log . $prof, $wgDebugLogFile );
 363         }
 364 }
 365
 366 /**
 367  * Check if the wiki read-only lock file is present. This can be used to lock
 368  * off editing functions, but doesn't guarantee that the database will not be
 369  * modified.
 370  * @return bool
 371  */
 372 function wfReadOnly() {
 373         global $wgReadOnlyFile, $wgReadOnly;
 374
 375         if ( !is_null( $wgReadOnly ) ) {
 376                 return (bool)$wgReadOnly;
 377         }
 378         if ( '' == $wgReadOnlyFile ) {
 379                 return false;
 380         }
 381         // Set $wgReadOnly for faster access next time
 382         if ( is_file( $wgReadOnlyFile ) ) {
 383                 $wgReadOnly = file_get_contents( $wgReadOnlyFile );
 384         } else {
 385                 $wgReadOnly = false;
 386         }
 387         return (bool)$wgReadOnly;
 388 }
 389
 390 function wfReadOnlyReason() {
 391         global $wgReadOnly;
 392         wfReadOnly();
 393         return $wgReadOnly;
 394 }
 395
 396 /**
 397  * Return a Language object from $langcode
 398  * @param $langcode Mixed: either:
 399  *                  - a Language object
 400  *                  - code of the language to get the message for, if it is
 401  *                    a valid code create a language for that language, if
 402  *                    it is a string but not a valid code then make a basic
 403  *                    language object
 404  *                  - a boolean: if it's false then use the current users
 405  *                    language (as a fallback for the old parameter
 406  *                    functionality), or if it is true then use the wikis
 407  * @return Language object
 408  */
 409 function wfGetLangObj( $langcode = false ){
 410         # Identify which language to get or create a language object for.
 411         if( $langcode instanceof Language )
 412                 # Great, we already have the object!
 413                 return $langcode;
 414
 415         global $wgContLang;
 416         if( $langcode === $wgContLang->getCode() || $langcode === true )
 417                 # $langcode is the language code of the wikis content language object.
 418                 # or it is a boolean and value is true
 419                 return $wgContLang;
 420
 421         global $wgLang;
 422         if( $langcode === $wgLang->getCode() || $langcode === false )
 423                 # $langcode is the language code of user language object.
 424                 # or it was a boolean and value is false
 425                 return $wgLang;
 426
 427         $validCodes = array_keys( Language::getLanguageNames() );
 428         if( in_array( $langcode, $validCodes ) )
 429                 # $langcode corresponds to a valid language.
 430                 return Language::factory( $langcode );
 431
 432         # $langcode is a string, but not a valid language code; use content language.
 433         wfDebug( 'Invalid language code passed to wfGetLangObj, falling back to content language.' );
 434         return $wgContLang;
 435 }
 436
 437 /**
 438  * Get a message from anywhere, for the current user language.
 439  *
 440  * Use wfMsgForContent() instead if the message should NOT
 441  * change depending on the user preferences.
 442  *
 443  * @param $key String: lookup key for the message, usually
 444  *    defined in languages/Language.php
 445  *
 446  * This function also takes extra optional parameters (not
 447  * shown in the function definition), which can by used to
 448  * insert variable text into the predefined message.
 449  */
 450 function wfMsg( $key ) {
 451         $args = func_get_args();
 452         array_shift( $args );
 453         return wfMsgReal( $key, $args, true );
 454 }
 455
 456 /**
 457  * Same as above except doesn't transform the message
 458  */
 459 function wfMsgNoTrans( $key ) {
 460         $args = func_get_args();
 461         array_shift( $args );
 462         return wfMsgReal( $key, $args, true, false, false );
 463 }
 464
 465 /**
 466  * Get a message from anywhere, for the current global language
 467  * set with $wgLanguageCode.
 468  *
 469  * Use this if the message should NOT change  dependent on the
 470  * language set in the user's preferences. This is the case for
 471  * most text written into logs, as well as link targets (such as
 472  * the name of the copyright policy page). Link titles, on the
 473  * other hand, should be shown in the UI language.
 474  *
 475  * Note that MediaWiki allows users to change the user interface
 476  * language in their preferences, but a single installation
 477  * typically only contains content in one language.
 478  *
 479  * Be wary of this distinction: If you use wfMsg() where you should
 480  * use wfMsgForContent(), a user of the software may have to
 481  * customize over 70 messages in order to, e.g., fix a link in every
 482  * possible language.
 483  *
 484  * @param $key String: lookup key for the message, usually
 485  *    defined in languages/Language.php
 486  */
 487 function wfMsgForContent( $key ) {
 488         global $wgForceUIMsgAsContentMsg;
 489         $args = func_get_args();
 490         array_shift( $args );
 491         $forcontent = true;
 492         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 493                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 494                 $forcontent = false;
 495         return wfMsgReal( $key, $args, true, $forcontent );
 496 }
 497
 498 /**
 499  * Same as above except doesn't transform the message
 500  */
 501 function wfMsgForContentNoTrans( $key ) {
 502         global $wgForceUIMsgAsContentMsg;
 503         $args = func_get_args();
 504         array_shift( $args );
 505         $forcontent = true;
 506         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 507                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 508                 $forcontent = false;
 509         return wfMsgReal( $key, $args, true, $forcontent, false );
 510 }
 511
 512 /**
 513  * Get a message from the language file, for the UI elements
 514  */
 515 function wfMsgNoDB( $key ) {
 516         $args = func_get_args();
 517         array_shift( $args );
 518         return wfMsgReal( $key, $args, false );
 519 }
 520
 521 /**
 522  * Get a message from the language file, for the content
 523  */
 524 function wfMsgNoDBForContent( $key ) {
 525         global $wgForceUIMsgAsContentMsg;
 526         $args = func_get_args();
 527         array_shift( $args );
 528         $forcontent = true;
 529         if( is_array( $wgForceUIMsgAsContentMsg ) &&
 530                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
 531                 $forcontent = false;
 532         return wfMsgReal( $key, $args, false, $forcontent );
 533 }
 534
 535
 536 /**
 537  * Really get a message
 538  * @param $key String: key to get.
 539  * @param $args
 540  * @param $useDB Boolean
 541  * @param $transform Boolean: Whether or not to transform the message.
 542  * @param $forContent Boolean
 543  * @return String: the requested message.
 544  */
 545 function wfMsgReal( $key, $args, $useDB = true, $forContent=false, $transform = true ) {
 546         wfProfileIn( __METHOD__ );
 547         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
 548         $message = wfMsgReplaceArgs( $message, $args );
 549         wfProfileOut( __METHOD__ );
 550         return $message;
 551 }
 552
 553 /**
 554  * This function provides the message source for messages to be edited which are *not* stored in the database.
 555  * @param $key String:
 556  */
 557 function wfMsgWeirdKey ( $key ) {
 558         $source = wfMsgGetKey( $key, false, true, false );
 559         if ( wfEmptyMsg( $key, $source ) )
 560                 return "";
 561         else
 562                 return $source;
 563 }
 564
 565 /**
 566  * Fetch a message string value, but don't replace any keys yet.
 567  * @param string $key
 568  * @param bool $useDB
 569  * @param string $langcode Code of the language to get the message for, or
 570  *                         behaves as a content language switch if it is a
 571  *                         boolean.
 572  * @return string
 573  * @private
 574  */
 575 function wfMsgGetKey( $key, $useDB, $langCode = false, $transform = true ) {
 576         global $wgContLang, $wgMessageCache;
 577
 578         wfRunHooks('NormalizeMessageKey', array(&$key, &$useDB, &$langCode, &$transform));
 579
 580         # If $wgMessageCache isn't initialised yet, try to return something sensible.
 581         if( is_object( $wgMessageCache ) ) {
 582                 $message = $wgMessageCache->get( $key, $useDB, $langCode );
 583                 if ( $transform ) {
 584                         $message = $wgMessageCache->transform( $message );
 585                 }
 586         } else {
 587                 $lang = wfGetLangObj( $langCode );
 588
 589                 # MessageCache::get() does this already, Language::getMessage() doesn't
 590                 # ISSUE: Should we try to handle "message/lang" here too?
 591                 $key = str_replace( ' ' , '_' , $wgContLang->lcfirst( $key ) );
 592
 593                 if( is_object( $lang ) ) {
 594                         $message = $lang->getMessage( $key );
 595                 } else {
 596                         $message = false;
 597                 }
 598         }
 599
 600         return $message;
 601 }
 602
 603 /**
 604  * Replace message parameter keys on the given formatted output.
 605  *
 606  * @param string $message
 607  * @param array $args
 608  * @return string
 609  * @private
 610  */
 611 function wfMsgReplaceArgs( $message, $args ) {
 612         # Fix windows line-endings
 613         # Some messages are split with explode("\n", $msg)
 614         $message = str_replace( "\r", '', $message );
 615
 616         // Replace arguments
 617         if ( count( $args ) ) {
 618                 if ( is_array( $args[0] ) ) {
 619                         $args = array_values( $args[0] );
 620                 }
 621                 $replacementKeys = array();
 622                 foreach( $args as $n => $param ) {
 623                         $replacementKeys['$' . ($n + 1)] = $param;
 624                 }
 625                 $message = strtr( $message, $replacementKeys );
 626         }
 627
 628         return $message;
 629 }
 630
 631 /**
 632  * Return an HTML-escaped version of a message.
 633  * Parameter replacements, if any, are done *after* the HTML-escaping,
 634  * so parameters may contain HTML (eg links or form controls). Be sure
 635  * to pre-escape them if you really do want plaintext, or just wrap
 636  * the whole thing in htmlspecialchars().
 637  *
 638  * @param string $key
 639  * @param string ... parameters
 640  * @return string
 641  */
 642 function wfMsgHtml( $key ) {
 643         $args = func_get_args();
 644         array_shift( $args );
 645         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key, true ) ), $args );
 646 }
 647
 648 /**
 649  * Return an HTML version of message
 650  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
 651  * so parameters may contain HTML (eg links or form controls). Be sure
 652  * to pre-escape them if you really do want plaintext, or just wrap
 653  * the whole thing in htmlspecialchars().
 654  *
 655  * @param string $key
 656  * @param string ... parameters
 657  * @return string
 658  */
 659 function wfMsgWikiHtml( $key ) {
 660         global $wgOut;
 661         $args = func_get_args();
 662         array_shift( $args );
 663         return wfMsgReplaceArgs( $wgOut->parse( wfMsgGetKey( $key, true ), /* can't be set to false */ true ), $args );
 664 }
 665
 666 /**
 667  * Returns message in the requested format
 668  * @param string $key Key of the message
 669  * @param array $options Processing rules:
 670  *  <i>parse</i>: parses wikitext to html
 671  *  <i>parseinline</i>: parses wikitext to html and removes the surrounding p's added by parser or tidy
 672  *  <i>escape</i>: filters message through htmlspecialchars
 673  *  <i>escapenoentities</i>: same, but allows entity references like &nbsp; through
 674  *  <i>replaceafter</i>: parameters are substituted after parsing or escaping
 675  *  <i>parsemag</i>: transform the message using magic phrases
 676  *  <i>content</i>: fetch message for content language instead of interface
 677  *  <i>language</i>: language code to fetch message for (overriden by <i>content</i>), its behaviour
 678  *                   with parser, parseinline and parsemag is undefined.
 679  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
 680  */
 681 function wfMsgExt( $key, $options ) {
 682         global $wgOut, $wgParser;
 683
 684         $args = func_get_args();
 685         array_shift( $args );
 686         array_shift( $args );
 687
 688         if( !is_array($options) ) {
 689                 $options = array($options);
 690         }
 691
 692         foreach( $options as $option ) {
 693                 if( !in_array( $option, array( 'parse', 'parseinline', 'escape',
 694                 'escapenoentities', 'replaceafter', 'parsemag', 'content',
 695                 'language' ) ) ) {
 696                         trigger_error( "wfMsgExt called with incorrect parameter $option",
 697                                 E_USER_WARNING );
 698                 }
 699         }
 700
 701         if( in_array('content', $options) ) {
 702                 $forContent = true;
 703                 $langCode = true;
 704         } elseif( array_key_exists('language', $options) ) {
 705                 $forContent = false;
 706                 $langCode = $options['language'];
 707                 $validCodes = array_keys( Language::getLanguageNames() );
 708                 if( !in_array($options['language'], $validCodes) ) {
 709                         # Fallback to en, instead of whatever interface language we might have
 710                         $langCode = 'en';
 711                 }
 712         } else {
 713                 $forContent = false;
 714                 $langCode = false;
 715         }
 716
 717         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
 718
 719         if( !in_array('replaceafter', $options) ) {
 720                 $string = wfMsgReplaceArgs( $string, $args );
 721         }
 722
 723         if( in_array('parse', $options) ) {
 724                 $string = $wgOut->parse( $string, true, !$forContent );
 725         } elseif ( in_array('parseinline', $options) ) {
 726                 $string = $wgOut->parse( $string, true, !$forContent );
 727                 $m = array();
 728                 if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
 729                         $string = $m[1];
 730                 }
 731         } elseif ( in_array('parsemag', $options) ) {
 732                 global $wgMessageCache;
 733                 if ( isset( $wgMessageCache ) ) {
 734                         $string = $wgMessageCache->transform( $string, !$forContent );
 735                 }
 736         }
 737
 738         if ( in_array('escape', $options) ) {
 739                 $string = htmlspecialchars ( $string );
 740         } elseif ( in_array( 'escapenoentities', $options ) ) {
 741                 $string = Sanitizer::escapeHtmlAllowEntities( $string );
 742         }
 743
 744         if( in_array('replaceafter', $options) ) {
 745                 $string = wfMsgReplaceArgs( $string, $args );
 746         }
 747
 748         return $string;
 749 }
 750
 751
 752 /**
 753  * Just like exit() but makes a note of it.
 754  * Commits open transactions except if the error parameter is set
 755  *
 756  * @deprecated Please return control to the caller or throw an exception
 757  */
 758 function wfAbruptExit( $error = false ){
 759         static $called = false;
 760         if ( $called ){
 761                 exit( -1 );
 762         }
 763         $called = true;
 764
 765         $bt = wfDebugBacktrace();
 766         if( $bt ) {
 767                 for($i = 0; $i < count($bt) ; $i++){
 768                         $file = isset($bt[$i]['file']) ? $bt[$i]['file'] : "unknown";
 769                         $line = isset($bt[$i]['line']) ? $bt[$i]['line'] : "unknown";
 770                         wfDebug("WARNING: Abrupt exit in $file at line $line\n");
 771                 }
 772         } else {
 773                 wfDebug('WARNING: Abrupt exit\n');
 774         }
 775
 776         wfLogProfilingData();
 777
 778         if ( !$error ) {
 779                 wfGetLB()->closeAll();
 780         }
 781         exit( -1 );
 782 }
 783
 784 /**
 785  * @deprecated Please return control the caller or throw an exception
 786  */
 787 function wfErrorExit() {
 788         wfAbruptExit( true );
 789 }
 790
 791 /**
 792  * Print a simple message and die, returning nonzero to the shell if any.
 793  * Plain die() fails to return nonzero to the shell if you pass a string.
 794  * @param string $msg
 795  */
 796 function wfDie( $msg='' ) {
 797         echo $msg;
 798         die( 1 );
 799 }
 800
 801 /**
 802  * Throw a debugging exception. This function previously once exited the process,
 803  * but now throws an exception instead, with similar results.
 804  *
 805  * @param string $msg Message shown when dieing.
 806  */
 807 function wfDebugDieBacktrace( $msg = '' ) {
 808         throw new MWException( $msg );
 809 }
 810
 811 /**
 812  * Fetch server name for use in error reporting etc.
 813  * Use real server name if available, so we know which machine
 814  * in a server farm generated the current page.
 815  * @return string
 816  */
 817 function wfHostname() {
 818         static $host;
 819         if ( is_null( $host ) ) {
 820                 if ( function_exists( 'posix_uname' ) ) {
 821                         // This function not present on Windows
 822                         $uname = @posix_uname();
 823                 } else {
 824                         $uname = false;
 825                 }
 826                 if( is_array( $uname ) && isset( $uname['nodename'] ) ) {
 827                         $host = $uname['nodename'];
 828                 } else {
 829                         # This may be a virtual server.
 830                         $host = $_SERVER['SERVER_NAME'];
 831                 }
 832         }
 833         return $host;
 834 }
 835
 836         /**
 837          * Returns a HTML comment with the elapsed time since request.
 838          * This method has no side effects.
 839          * @return string
 840          */
 841         function wfReportTime() {
 842                 global $wgRequestTime, $wgShowHostnames;
 843
 844                 $now = wfTime();
 845                 $elapsed = $now - $wgRequestTime;
 846
 847                 return $wgShowHostnames
 848                         ? sprintf( "<!-- Served by %s in %01.3f secs. -->", wfHostname(), $elapsed )
 849                         : sprintf( "<!-- Served in %01.3f secs. -->", $elapsed );
 850         }
 851
 852 /**
 853  * Safety wrapper for debug_backtrace().
 854  *
 855  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
 856  * murky circumstances, which may be triggered in part by stub objects
 857  * or other fancy talkin'.
 858  *
 859  * Will return an empty array if Zend Optimizer is detected, otherwise
 860  * the output from debug_backtrace() (trimmed).
 861  *
 862  * @return array of backtrace information
 863  */
 864 function wfDebugBacktrace() {
 865         if( extension_loaded( 'Zend Optimizer' ) ) {
 866                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
 867                 return array();
 868         } else {
 869                 return array_slice( debug_backtrace(), 1 );
 870         }
 871 }
 872
 873 function wfBacktrace() {
 874         global $wgCommandLineMode;
 875
 876         if ( $wgCommandLineMode ) {
 877                 $msg = '';
 878         } else {
 879                 $msg = "<ul>\n";
 880         }
 881         $backtrace = wfDebugBacktrace();
 882         foreach( $backtrace as $call ) {
 883                 if( isset( $call['file'] ) ) {
 884                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
 885                         $file = $f[count($f)-1];
 886                 } else {
 887                         $file = '-';
 888                 }
 889                 if( isset( $call['line'] ) ) {
 890                         $line = $call['line'];
 891                 } else {
 892                         $line = '-';
 893                 }
 894                 if ( $wgCommandLineMode ) {
 895                         $msg .= "$file line $line calls ";
 896                 } else {
 897                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
 898                 }
 899                 if( !empty( $call['class'] ) ) $msg .= $call['class'] . '::';
 900                 $msg .= $call['function'] . '()';
 901
 902                 if ( $wgCommandLineMode ) {
 903                         $msg .= "\n";
 904                 } else {
 905                         $msg .= "</li>\n";
 906                 }
 907         }
 908         if ( $wgCommandLineMode ) {
 909                 $msg .= "\n";
 910         } else {
 911                 $msg .= "</ul>\n";
 912         }
 913
 914         return $msg;
 915 }
 916
 917
 918 /* Some generic result counters, pulled out of SearchEngine */
 919
 920
 921 /**
 922  * @todo document
 923  */
 924 function wfShowingResults( $offset, $limit ) {
 925         global $wgLang;
 926         return wfMsgExt( 'showingresults', array( 'parseinline' ), $wgLang->formatNum( $limit ), $wgLang->formatNum( $offset+1 ) );
 927 }
 928
 929 /**
 930  * @todo document
 931  */
 932 function wfShowingResultsNum( $offset, $limit, $num ) {
 933         global $wgLang;
 934         return wfMsgExt( 'showingresultsnum', array( 'parseinline' ), $wgLang->formatNum( $limit ), $wgLang->formatNum( $offset+1 ), $wgLang->formatNum( $num ) );
 935 }
 936
 937 /**
 938  * @todo document
 939  */
 940 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
 941         global $wgLang;
 942         $fmtLimit = $wgLang->formatNum( $limit );
 943         $prev = wfMsg( 'prevn', $fmtLimit );
 944         $next = wfMsg( 'nextn', $fmtLimit );
 945
 946         if( is_object( $link ) ) {
 947                 $title =& $link;
 948         } else {
 949                 $title = Title::newFromText( $link );
 950                 if( is_null( $title ) ) {
 951                         return false;
 952                 }
 953         }
 954
 955         if ( 0 != $offset ) {
 956                 $po = $offset - $limit;
 957                 if ( $po < 0 ) { $po = 0; }
 958                 $q = "limit={$limit}&offset={$po}";
 959                 if ( '' != $query ) { $q .= '&'.$query; }
 960                 $plink = '<a href="' . $title->escapeLocalUrl( $q ) . "\" class=\"mw-prevlink\">{$prev}</a>";
 961         } else { $plink = $prev; }
 962
 963         $no = $offset + $limit;
 964         $q = 'limit='.$limit.'&offset='.$no;
 965         if ( '' != $query ) { $q .= '&'.$query; }
 966
 967         if ( $atend ) {
 968                 $nlink = $next;
 969         } else {
 970                 $nlink = '<a href="' . $title->escapeLocalUrl( $q ) . "\" class=\"mw-nextlink\">{$next}</a>";
 971         }
 972         $nums = wfNumLink( $offset, 20, $title, $query ) . ' | ' .
 973           wfNumLink( $offset, 50, $title, $query ) . ' | ' .
 974           wfNumLink( $offset, 100, $title, $query ) . ' | ' .
 975           wfNumLink( $offset, 250, $title, $query ) . ' | ' .
 976           wfNumLink( $offset, 500, $title, $query );
 977
 978         return wfMsg( 'viewprevnext', $plink, $nlink, $nums );
 979 }
 980
 981 /**
 982  * @todo document
 983  */
 984 function wfNumLink( $offset, $limit, &$title, $query = '' ) {
 985         global $wgLang;
 986         if ( '' == $query ) { $q = ''; }
 987         else { $q = $query.'&'; }
 988         $q .= 'limit='.$limit.'&offset='.$offset;
 989
 990         $fmtLimit = $wgLang->formatNum( $limit );
 991         $s = '<a href="' . $title->escapeLocalUrl( $q ) . "\" class=\"mw-numlink\">{$fmtLimit}</a>";
 992         return $s;
 993 }
 994
 995 /**
 996  * @todo document
 997  * @todo FIXME: we may want to blacklist some broken browsers
 998  *
 999  * @return bool Whereas client accept gzip compression
1000  */
1001 function wfClientAcceptsGzip() {
1002         global $wgUseGzip;
1003         if( $wgUseGzip ) {
1004                 # FIXME: we may want to blacklist some broken browsers
1005                 $m = array();
1006                 if( preg_match(
1007                         '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1008                         $_SERVER['HTTP_ACCEPT_ENCODING'],
1009                         $m ) ) {
1010                         if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) return false;
1011                         wfDebug( " accepts gzip\n" );
1012                         return true;
1013                 }
1014         }
1015         return false;
1016 }
1017
1018 /**
1019  * Obtain the offset and limit values from the request string;
1020  * used in special pages
1021  *
1022  * @param $deflimit Default limit if none supplied
1023  * @param $optionname Name of a user preference to check against
1024  * @return array
1025  *
1026  */
1027 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
1028         global $wgRequest;
1029         return $wgRequest->getLimitOffset( $deflimit, $optionname );
1030 }
1031
1032 /**
1033  * Escapes the given text so that it may be output using addWikiText()
1034  * without any linking, formatting, etc. making its way through. This
1035  * is achieved by substituting certain characters with HTML entities.
1036  * As required by the callers, <nowiki> is not used. It currently does
1037  * not filter out characters which have special meaning only at the
1038  * start of a line, such as "*".
1039  *
1040  * @param string $text Text to be escaped
1041  */
1042 function wfEscapeWikiText( $text ) {
1043         $text = str_replace(
1044                 array( '[',     '|',      ']',     '\'',    'ISBN ',     'RFC ',     '://',     "\n=",     '{{' ),
1045                 array( '&#91;', '&#124;', '&#93;', '&#39;', 'ISBN&#32;', 'RFC&#32;', '&#58;//', "\n&#61;", '&#123;&#123;' ),
1046                 htmlspecialchars($text) );
1047         return $text;
1048 }
1049
1050 /**
1051  * @todo document
1052  */
1053 function wfQuotedPrintable( $string, $charset = '' ) {
1054         # Probably incomplete; see RFC 2045
1055         if( empty( $charset ) ) {
1056                 global $wgInputEncoding;
1057                 $charset = $wgInputEncoding;
1058         }
1059         $charset = strtoupper( $charset );
1060         $charset = str_replace( 'ISO-8859', 'ISO8859', $charset ); // ?
1061
1062         $illegal = '\x00-\x08\x0b\x0c\x0e-\x1f\x7f-\xff=';
1063         $replace = $illegal . '\t ?_';
1064         if( !preg_match( "/[$illegal]/", $string ) ) return $string;
1065         $out = "=?$charset?Q?";
1066         $out .= preg_replace( "/([$replace])/e", 'sprintf("=%02X",ord("$1"))', $string );
1067         $out .= '?=';
1068         return $out;
1069 }
1070
1071
1072 /**
1073  * @todo document
1074  * @return float
1075  */
1076 function wfTime() {
1077         return microtime(true);
1078 }
1079
1080 /**
1081  * Sets dest to source and returns the original value of dest
1082  * If source is NULL, it just returns the value, it doesn't set the variable
1083  */
1084 function wfSetVar( &$dest, $source ) {
1085         $temp = $dest;
1086         if ( !is_null( $source ) ) {
1087                 $dest = $source;
1088         }
1089         return $temp;
1090 }
1091
1092 /**
1093  * As for wfSetVar except setting a bit
1094  */
1095 function wfSetBit( &$dest, $bit, $state = true ) {
1096         $temp = (bool)($dest & $bit );
1097         if ( !is_null( $state ) ) {
1098                 if ( $state ) {
1099                         $dest |= $bit;
1100                 } else {
1101                         $dest &= ~$bit;
1102                 }
1103         }
1104         return $temp;
1105 }
1106
1107 /**
1108  * This function takes two arrays as input, and returns a CGI-style string, e.g.
1109  * "days=7&limit=100". Options in the first array override options in the second.
1110  * Options set to "" will not be output.
1111  */
1112 function wfArrayToCGI( $array1, $array2 = NULL )
1113 {
1114         if ( !is_null( $array2 ) ) {
1115                 $array1 = $array1 + $array2;
1116         }
1117
1118         $cgi = '';
1119         foreach ( $array1 as $key => $value ) {
1120                 if ( '' !== $value ) {
1121                         if ( '' != $cgi ) {
1122                                 $cgi .= '&';
1123                         }
1124                         if(is_array($value))
1125                         {
1126                                 $firstTime = true;
1127                                 foreach($value as $v)
1128                                 {
1129                                         $cgi .= ($firstTime ? '' : '&') .
1130                                                 urlencode( $key . '[]' ) . '=' .
1131                                                 urlencode( $v );
1132                                         $firstTime = false;
1133                                 }
1134                         }
1135                         else
1136                                 $cgi .= urlencode( $key ) . '=' .
1137                                         urlencode( $value );
1138                 }
1139         }
1140         return $cgi;
1141 }
1142
1143 /**
1144  * This is the logical opposite of wfArrayToCGI(): it accepts a query string as
1145  * its argument and returns the same string in array form.  This allows compa-
1146  * tibility with legacy functions that accept raw query strings instead of nice
1147  * arrays.  Of course, keys and values are urldecode()d.  Don't try passing in-
1148  * valid query strings, or it will explode.
1149  *
1150  * @param $query string Query string
1151  * @return array Array version of input
1152  */
1153 function wfCgiToArray( $query ) {
1154         if( isset( $query[0] ) and $query[0] == '?' ) {
1155                 $query = substr( $query, 1 );
1156         }
1157         $bits = explode( '&', $query );
1158         $ret = array();
1159         foreach( $bits as $bit ) {
1160                 if( $bit === '' ) {
1161                         continue;
1162                 }
1163                 list( $key, $value ) = explode( '=', $bit );
1164                 $key = urldecode( $key );
1165                 $value = urldecode( $value );
1166                 $ret[$key] = $value;
1167         }
1168         return $ret;
1169 }
1170
1171 /**
1172  * Append a query string to an existing URL, which may or may not already
1173  * have query string parameters already. If so, they will be combined.
1174  *
1175  * @param string $url
1176  * @param string $query
1177  * @return string
1178  */
1179 function wfAppendQuery( $url, $query ) {
1180         if( $query != '' ) {
1181                 if( false === strpos( $url, '?' ) ) {
1182                         $url .= '?';
1183                 } else {
1184                         $url .= '&';
1185                 }
1186                 $url .= $query;
1187         }
1188         return $url;
1189 }
1190
1191 /**
1192  * Expand a potentially local URL to a fully-qualified URL.
1193  * Assumes $wgServer is correct. :)
1194  * @param string $url, either fully-qualified or a local path + query
1195  * @return string Fully-qualified URL
1196  */
1197 function wfExpandUrl( $url ) {
1198         if( substr( $url, 0, 1 ) == '/' ) {
1199                 global $wgServer;
1200                 return $wgServer . $url;
1201         } else {
1202                 return $url;
1203         }
1204 }
1205
1206 /**
1207  * This is obsolete, use SquidUpdate::purge()
1208  * @deprecated
1209  */
1210 function wfPurgeSquidServers ($urlArr) {
1211         SquidUpdate::purge( $urlArr );
1212 }
1213
1214 /**
1215  * Windows-compatible version of escapeshellarg()
1216  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
1217  * function puts single quotes in regardless of OS
1218  */
1219 function wfEscapeShellArg( ) {
1220         $args = func_get_args();
1221         $first = true;
1222         $retVal = '';
1223         foreach ( $args as $arg ) {
1224                 if ( !$first ) {
1225                         $retVal .= ' ';
1226                 } else {
1227                         $first = false;
1228                 }
1229
1230                 if ( wfIsWindows() ) {
1231                         // Escaping for an MSVC-style command line parser
1232                         // Ref: http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
1233                         // Double the backslashes before any double quotes. Escape the double quotes.
1234                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
1235                         $arg = '';
1236                         $delim = false;
1237                         foreach ( $tokens as $token ) {
1238                                 if ( $delim ) {
1239                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
1240                                 } else {
1241                                         $arg .= $token;
1242                                 }
1243                                 $delim = !$delim;
1244                         }
1245                         // Double the backslashes before the end of the string, because
1246                         // we will soon add a quote
1247                         $m = array();
1248                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
1249                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
1250                         }
1251
1252                         // Add surrounding quotes
1253                         $retVal .= '"' . $arg . '"';
1254                 } else {
1255                         $retVal .= escapeshellarg( $arg );
1256                 }
1257         }
1258         return $retVal;
1259 }
1260
1261 /**
1262  * wfMerge attempts to merge differences between three texts.
1263  * Returns true for a clean merge and false for failure or a conflict.
1264  */
1265 function wfMerge( $old, $mine, $yours, &$result ){
1266         global $wgDiff3;
1267
1268         # This check may also protect against code injection in
1269         # case of broken installations.
1270         if(! file_exists( $wgDiff3 ) ){
1271                 wfDebug( "diff3 not found\n" );
1272                 return false;
1273         }
1274
1275         # Make temporary files
1276         $td = wfTempDir();
1277         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1278         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
1279         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
1280
1281         fwrite( $oldtextFile, $old ); fclose( $oldtextFile );
1282         fwrite( $mytextFile, $mine ); fclose( $mytextFile );
1283         fwrite( $yourtextFile, $yours ); fclose( $yourtextFile );
1284
1285         # Check for a conflict
1286         $cmd = $wgDiff3 . ' -a --overlap-only ' .
1287           wfEscapeShellArg( $mytextName ) . ' ' .
1288           wfEscapeShellArg( $oldtextName ) . ' ' .
1289           wfEscapeShellArg( $yourtextName );
1290         $handle = popen( $cmd, 'r' );
1291
1292         if( fgets( $handle, 1024 ) ){
1293                 $conflict = true;
1294         } else {
1295                 $conflict = false;
1296         }
1297         pclose( $handle );
1298
1299         # Merge differences
1300         $cmd = $wgDiff3 . ' -a -e --merge ' .
1301           wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
1302         $handle = popen( $cmd, 'r' );
1303         $result = '';
1304         do {
1305                 $data = fread( $handle, 8192 );
1306                 if ( strlen( $data ) == 0 ) {
1307                         break;
1308                 }
1309                 $result .= $data;
1310         } while ( true );
1311         pclose( $handle );
1312         unlink( $mytextName ); unlink( $oldtextName ); unlink( $yourtextName );
1313
1314         if ( $result === '' && $old !== '' && $conflict == false ) {
1315                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
1316                 $conflict = true;
1317         }
1318         return ! $conflict;
1319 }
1320
1321 /**
1322  * Returns unified plain-text diff of two texts.
1323  * Useful for machine processing of diffs.
1324  * @param $before string The text before the changes.
1325  * @param $after string The text after the changes.
1326  * @param $params string Command-line options for the diff command.
1327  * @return string Unified diff of $before and $after
1328  */
1329 function wfDiff( $before, $after, $params = '-u' ) {
1330         global $wgDiff;
1331
1332         # This check may also protect against code injection in
1333         # case of broken installations.
1334         if( !file_exists( $wgDiff ) ){
1335                 wfDebug( "diff executable not found\n" );
1336                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
1337                 $format = new UnifiedDiffFormatter();
1338                 return $format->format( $diffs );
1339         }
1340
1341         # Make temporary files
1342         $td = wfTempDir();
1343         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1344         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
1345
1346         fwrite( $oldtextFile, $before ); fclose( $oldtextFile );
1347         fwrite( $newtextFile, $after ); fclose( $newtextFile );
1348
1349         // Get the diff of the two files
1350         $cmd = "$wgDiff " . $params . ' ' .wfEscapeShellArg( $oldtextName, $newtextName );
1351
1352         $h = popen( $cmd, 'r' );
1353
1354         $diff = '';
1355
1356         do {
1357                 $data = fread( $h, 8192 );
1358                 if ( strlen( $data ) == 0 ) {
1359                         break;
1360                 }
1361                 $diff .= $data;
1362         } while ( true );
1363
1364         // Clean up
1365         pclose( $h );
1366         unlink( $oldtextName );
1367         unlink( $newtextName );
1368
1369         // Kill the --- and +++ lines. They're not useful.
1370         $diff_lines = explode( "\n", $diff );
1371         if (strpos( $diff_lines[0], '---' ) === 0) {
1372                 unset($diff_lines[0]);
1373         }
1374         if (strpos( $diff_lines[1], '+++' ) === 0) {
1375                 unset($diff_lines[1]);
1376         }
1377
1378         $diff = implode( "\n", $diff_lines );
1379
1380         return $diff;
1381 }
1382
1383 /**
1384  * @todo document
1385  */
1386 function wfVarDump( $var ) {
1387         global $wgOut;
1388         $s = str_replace("\n","<br />\n", var_export( $var, true ) . "\n");
1389         if ( headers_sent() || !@is_object( $wgOut ) ) {
1390                 print $s;
1391         } else {
1392                 $wgOut->addHTML( $s );
1393         }
1394 }
1395
1396 /**
1397  * Provide a simple HTTP error.
1398  */
1399 function wfHttpError( $code, $label, $desc ) {
1400         global $wgOut;
1401         $wgOut->disable();
1402         header( "HTTP/1.0 $code $label" );
1403         header( "Status: $code $label" );
1404         $wgOut->sendCacheControl();
1405
1406         header( 'Content-type: text/html; charset=utf-8' );
1407         print "<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">".
1408                 "<html><head><title>" .
1409                 htmlspecialchars( $label ) .
1410                 "</title></head><body><h1>" .
1411                 htmlspecialchars( $label ) .
1412                 "</h1><p>" .
1413                 nl2br( htmlspecialchars( $desc ) ) .
1414                 "</p></body></html>\n";
1415 }
1416
1417 /**
1418  * Clear away any user-level output buffers, discarding contents.
1419  *
1420  * Suitable for 'starting afresh', for instance when streaming
1421  * relatively large amounts of data without buffering, or wanting to
1422  * output image files without ob_gzhandler's compression.
1423  *
1424  * The optional $resetGzipEncoding parameter controls suppression of
1425  * the Content-Encoding header sent by ob_gzhandler; by default it
1426  * is left. See comments for wfClearOutputBuffers() for why it would
1427  * be used.
1428  *
1429  * Note that some PHP configuration options may add output buffer
1430  * layers which cannot be removed; these are left in place.
1431  *
1432  * @param bool $resetGzipEncoding
1433  */
1434 function wfResetOutputBuffers( $resetGzipEncoding=true ) {
1435         if( $resetGzipEncoding ) {
1436                 // Suppress Content-Encoding and Content-Length
1437                 // headers from 1.10+s wfOutputHandler
1438                 global $wgDisableOutputCompression;
1439                 $wgDisableOutputCompression = true;
1440         }
1441         while( $status = ob_get_status() ) {
1442                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
1443                         // Probably from zlib.output_compression or other
1444                         // PHP-internal setting which can't be removed.
1445                         //
1446                         // Give up, and hope the result doesn't break
1447                         // output behavior.
1448                         break;
1449                 }
1450                 if( !ob_end_clean() ) {
1451                         // Could not remove output buffer handler; abort now
1452                         // to avoid getting in some kind of infinite loop.
1453                         break;
1454                 }
1455                 if( $resetGzipEncoding ) {
1456                         if( $status['name'] == 'ob_gzhandler' ) {
1457                                 // Reset the 'Content-Encoding' field set by this handler
1458                                 // so we can start fresh.
1459                                 header( 'Content-Encoding:' );
1460                                 break;
1461                         }
1462                 }
1463         }
1464 }
1465
1466 /**
1467  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
1468  *
1469  * Clear away output buffers, but keep the Content-Encoding header
1470  * produced by ob_gzhandler, if any.
1471  *
1472  * This should be used for HTTP 304 responses, where you need to
1473  * preserve the Content-Encoding header of the real result, but
1474  * also need to suppress the output of ob_gzhandler to keep to spec
1475  * and avoid breaking Firefox in rare cases where the headers and
1476  * body are broken over two packets.
1477  */
1478 function wfClearOutputBuffers() {
1479         wfResetOutputBuffers( false );
1480 }
1481
1482 /**
1483  * Converts an Accept-* header into an array mapping string values to quality
1484  * factors
1485  */
1486 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
1487         # No arg means accept anything (per HTTP spec)
1488         if( !$accept ) {
1489                 return array( $def => 1.0 );
1490         }
1491
1492         $prefs = array();
1493
1494         $parts = explode( ',', $accept );
1495
1496         foreach( $parts as $part ) {
1497                 # FIXME: doesn't deal with params like 'text/html; level=1'
1498                 @list( $value, $qpart ) = explode( ';', trim( $part ) );
1499                 $match = array();
1500                 if( !isset( $qpart ) ) {
1501                         $prefs[$value] = 1.0;
1502                 } elseif( preg_match( '/q\s*=\s*(\d*\.\d+)/', $qpart, $match ) ) {
1503                         $prefs[$value] = floatval($match[1]);
1504                 }
1505         }
1506
1507         return $prefs;
1508 }
1509
1510 /**
1511  * Checks if a given MIME type matches any of the keys in the given
1512  * array. Basic wildcards are accepted in the array keys.
1513  *
1514  * Returns the matching MIME type (or wildcard) if a match, otherwise
1515  * NULL if no match.
1516  *
1517  * @param string $type
1518  * @param array $avail
1519  * @return string
1520  * @private
1521  */
1522 function mimeTypeMatch( $type, $avail ) {
1523         if( array_key_exists($type, $avail) ) {
1524                 return $type;
1525         } else {
1526                 $parts = explode( '/', $type );
1527                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
1528                         return $parts[0] . '/*';
1529                 } elseif( array_key_exists( '*/*', $avail ) ) {
1530                         return '*/*';
1531                 } else {
1532                         return NULL;
1533                 }
1534         }
1535 }
1536
1537 /**
1538  * Returns the 'best' match between a client's requested internet media types
1539  * and the server's list of available types. Each list should be an associative
1540  * array of type to preference (preference is a float between 0.0 and 1.0).
1541  * Wildcards in the types are acceptable.
1542  *
1543  * @param array $cprefs Client's acceptable type list
1544  * @param array $sprefs Server's offered types
1545  * @return string
1546  *
1547  * @todo FIXME: doesn't handle params like 'text/plain; charset=UTF-8'
1548  * XXX: generalize to negotiate other stuff
1549  */
1550 function wfNegotiateType( $cprefs, $sprefs ) {
1551         $combine = array();
1552
1553         foreach( array_keys($sprefs) as $type ) {
1554                 $parts = explode( '/', $type );
1555                 if( $parts[1] != '*' ) {
1556                         $ckey = mimeTypeMatch( $type, $cprefs );
1557                         if( $ckey ) {
1558                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
1559                         }
1560                 }
1561         }
1562
1563         foreach( array_keys( $cprefs ) as $type ) {
1564                 $parts = explode( '/', $type );
1565                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
1566                         $skey = mimeTypeMatch( $type, $sprefs );
1567                         if( $skey ) {
1568                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
1569                         }
1570                 }
1571         }
1572
1573         $bestq = 0;
1574         $besttype = NULL;
1575
1576         foreach( array_keys( $combine ) as $type ) {
1577                 if( $combine[$type] > $bestq ) {
1578                         $besttype = $type;
1579                         $bestq = $combine[$type];
1580                 }
1581         }
1582
1583         return $besttype;
1584 }
1585
1586 /**
1587  * Array lookup
1588  * Returns an array where the values in the first array are replaced by the
1589  * values in the second array with the corresponding keys
1590  *
1591  * @return array
1592  */
1593 function wfArrayLookup( $a, $b ) {
1594         return array_flip( array_intersect( array_flip( $a ), array_keys( $b ) ) );
1595 }
1596
1597 /**
1598  * Convenience function; returns MediaWiki timestamp for the present time.
1599  * @return string
1600  */
1601 function wfTimestampNow() {
1602         # return NOW
1603         return wfTimestamp( TS_MW, time() );
1604 }
1605
1606 /**
1607  * Reference-counted warning suppression
1608  */
1609 function wfSuppressWarnings( $end = false ) {
1610         static $suppressCount = 0;
1611         static $originalLevel = false;
1612
1613         if ( $end ) {
1614                 if ( $suppressCount ) {
1615                         --$suppressCount;
1616                         if ( !$suppressCount ) {
1617                                 error_reporting( $originalLevel );
1618                         }
1619                 }
1620         } else {
1621                 if ( !$suppressCount ) {
1622                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE ) );
1623                 }
1624                 ++$suppressCount;
1625         }
1626 }
1627
1628 /**
1629  * Restore error level to previous value
1630  */
1631 function wfRestoreWarnings() {
1632         wfSuppressWarnings( true );
1633 }
1634
1635 # Autodetect, convert and provide timestamps of various types
1636
1637 /**
1638  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
1639  */
1640 define('TS_UNIX', 0);
1641
1642 /**
1643  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
1644  */
1645 define('TS_MW', 1);
1646
1647 /**
1648  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
1649  */
1650 define('TS_DB', 2);
1651
1652 /**
1653  * RFC 2822 format, for E-mail and HTTP headers
1654  */
1655 define('TS_RFC2822', 3);
1656
1657 /**
1658  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
1659  *
1660  * This is used by Special:Export
1661  */
1662 define('TS_ISO_8601', 4);
1663
1664 /**
1665  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
1666  *
1667  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
1668  *       DateTime tag and page 36 for the DateTimeOriginal and
1669  *       DateTimeDigitized tags.
1670  */
1671 define('TS_EXIF', 5);
1672
1673 /**
1674  * Oracle format time.
1675  */
1676 define('TS_ORACLE', 6);
1677
1678 /**
1679  * Postgres format time.
1680  */
1681 define('TS_POSTGRES', 7);
1682
1683 /**
1684  * @param mixed $outputtype A timestamp in one of the supported formats, the
1685  *                          function will autodetect which format is supplied
1686  *                          and act accordingly.
1687  * @return string Time in the format specified in $outputtype
1688  */
1689 function wfTimestamp($outputtype=TS_UNIX,$ts=0) {
1690         $uts = 0;
1691         $da = array();
1692         if ($ts==0) {
1693                 $uts=time();
1694         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/D',$ts,$da)) {
1695                 # TS_DB
1696         } elseif (preg_match('/^(\d{4}):(\d\d):(\d\d) (\d\d):(\d\d):(\d\d)$/D',$ts,$da)) {
1697                 # TS_EXIF
1698         } elseif (preg_match('/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/D',$ts,$da)) {
1699                 # TS_MW
1700         } elseif (preg_match('/^\d{1,13}$/D',$ts)) {
1701                 # TS_UNIX
1702                 $uts = $ts;
1703         } elseif (preg_match('/^\d{1,2}-...-\d\d(?:\d\d)? \d\d\.\d\d\.\d\d/', $ts)) {
1704                 # TS_ORACLE
1705                 $uts = strtotime(preg_replace('/(\d\d)\.(\d\d)\.(\d\d)(\.(\d+))?/', "$1:$2:$3",
1706                                 str_replace("+00:00", "UTC", $ts)));
1707         } elseif (preg_match('/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})Z$/', $ts, $da)) {
1708                 # TS_ISO_8601
1709         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)[\+\- ](\d\d)$/',$ts,$da)) {
1710                 # TS_POSTGRES
1711         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d) GMT$/',$ts,$da)) {
1712                 # TS_POSTGRES
1713         } else {
1714                 # Bogus value; fall back to the epoch...
1715                 wfDebug("wfTimestamp() fed bogus time value: $outputtype; $ts\n");
1716                 $uts = 0;
1717         }
1718
1719         if (count( $da ) ) {
1720                 // Warning! gmmktime() acts oddly if the month or day is set to 0
1721                 // We may want to handle that explicitly at some point
1722                 $uts=gmmktime((int)$da[4],(int)$da[5],(int)$da[6],
1723                         (int)$da[2],(int)$da[3],(int)$da[1]);
1724         }
1725
1726         switch($outputtype) {
1727                 case TS_UNIX:
1728                         return $uts;
1729                 case TS_MW:
1730                         return gmdate( 'YmdHis', $uts );
1731                 case TS_DB:
1732                         return gmdate( 'Y-m-d H:i:s', $uts );
1733                 case TS_ISO_8601:
1734                         return gmdate( 'Y-m-d\TH:i:s\Z', $uts );
1735                 // This shouldn't ever be used, but is included for completeness
1736                 case TS_EXIF:
1737                         return gmdate(  'Y:m:d H:i:s', $uts );
1738                 case TS_RFC2822:
1739                         return gmdate( 'D, d M Y H:i:s', $uts ) . ' GMT';
1740                 case TS_ORACLE:
1741                         return gmdate( 'd-M-y h.i.s A', $uts) . ' +00:00';
1742                 case TS_POSTGRES:
1743                         return gmdate( 'Y-m-d H:i:s', $uts) . ' GMT';
1744                 default:
1745                         throw new MWException( 'wfTimestamp() called with illegal output type.');
1746         }
1747 }
1748
1749 /**
1750  * Return a formatted timestamp, or null if input is null.
1751  * For dealing with nullable timestamp columns in the database.
1752  * @param int $outputtype
1753  * @param string $ts
1754  * @return string
1755  */
1756 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
1757         if( is_null( $ts ) ) {
1758                 return null;
1759         } else {
1760                 return wfTimestamp( $outputtype, $ts );
1761         }
1762 }
1763
1764 /**
1765  * Check if the operating system is Windows
1766  *
1767  * @return bool True if it's Windows, False otherwise.
1768  */
1769 function wfIsWindows() {
1770         if (substr(php_uname(), 0, 7) == 'Windows') {
1771                 return true;
1772         } else {
1773                 return false;
1774         }
1775 }
1776
1777 /**
1778  * Swap two variables
1779  */
1780 function swap( &$x, &$y ) {
1781         $z = $x;
1782         $x = $y;
1783         $y = $z;
1784 }
1785
1786 function wfGetCachedNotice( $name ) {
1787         global $wgOut, $wgRenderHashAppend, $parserMemc;
1788         $fname = 'wfGetCachedNotice';
1789         wfProfileIn( $fname );
1790
1791         $needParse = false;
1792
1793         if( $name === 'default' ) {
1794                 // special case
1795                 global $wgSiteNotice;
1796                 $notice = $wgSiteNotice;
1797                 if( empty( $notice ) ) {
1798                         wfProfileOut( $fname );
1799                         return false;
1800                 }
1801         } else {
1802                 $notice = wfMsgForContentNoTrans( $name );
1803                 if( wfEmptyMsg( $name, $notice ) || $notice == '-' ) {
1804                         wfProfileOut( $fname );
1805                         return( false );
1806                 }
1807         }
1808
1809         // Use the extra hash appender to let eg SSL variants separately cache.
1810         $key = wfMemcKey( $name . $wgRenderHashAppend );
1811         $cachedNotice = $parserMemc->get( $key );
1812         if( is_array( $cachedNotice ) ) {
1813                 if( md5( $notice ) == $cachedNotice['hash'] ) {
1814                         $notice = $cachedNotice['html'];
1815                 } else {
1816                         $needParse = true;
1817                 }
1818         } else {
1819                 $needParse = true;
1820         }
1821
1822         if( $needParse ) {
1823                 if( is_object( $wgOut ) ) {
1824                         $parsed = $wgOut->parse( $notice );
1825                         $parserMemc->set( $key, array( 'html' => $parsed, 'hash' => md5( $notice ) ), 600 );
1826                         $notice = $parsed;
1827                 } else {
1828                         wfDebug( 'wfGetCachedNotice called for ' . $name . ' with no $wgOut available' );
1829                         $notice = '';
1830                 }
1831         }
1832
1833         wfProfileOut( $fname );
1834         return $notice;
1835 }
1836
1837 function wfGetNamespaceNotice() {
1838         global $wgTitle;
1839
1840         # Paranoia
1841         if ( !isset( $wgTitle ) || !is_object( $wgTitle ) )
1842                 return "";
1843
1844         $fname = 'wfGetNamespaceNotice';
1845         wfProfileIn( $fname );
1846
1847         $key = "namespacenotice-" . $wgTitle->getNsText();
1848         $namespaceNotice = wfGetCachedNotice( $key );
1849         if ( $namespaceNotice && substr ( $namespaceNotice , 0 ,7 ) != "<p>&lt;" ) {
1850                  $namespaceNotice = '<div id="namespacebanner">' . $namespaceNotice . "</div>";
1851         } else {
1852                 $namespaceNotice = "";
1853         }
1854
1855         wfProfileOut( $fname );
1856         return $namespaceNotice;
1857 }
1858
1859 function wfGetSiteNotice() {
1860         global $wgUser, $wgSiteNotice;
1861         $fname = 'wfGetSiteNotice';
1862         wfProfileIn( $fname );
1863         $siteNotice = '';
1864
1865         if( wfRunHooks( 'SiteNoticeBefore', array( &$siteNotice ) ) ) {
1866                 if( is_object( $wgUser ) && $wgUser->isLoggedIn() ) {
1867                         $siteNotice = wfGetCachedNotice( 'sitenotice' );
1868                 } else {
1869                         $anonNotice = wfGetCachedNotice( 'anonnotice' );
1870                         if( !$anonNotice ) {
1871                                 $siteNotice = wfGetCachedNotice( 'sitenotice' );
1872                         } else {
1873                                 $siteNotice = $anonNotice;
1874                         }
1875                 }
1876                 if( !$siteNotice ) {
1877                         $siteNotice = wfGetCachedNotice( 'default' );
1878                 }
1879         }
1880
1881         wfRunHooks( 'SiteNoticeAfter', array( &$siteNotice ) );
1882         wfProfileOut( $fname );
1883         return $siteNotice;
1884 }
1885
1886 /**
1887  * BC wrapper for MimeMagic::singleton()
1888  * @deprecated
1889  */
1890 function &wfGetMimeMagic() {
1891         return MimeMagic::singleton();
1892 }
1893
1894 /**
1895  * Tries to get the system directory for temporary files.
1896  * The TMPDIR, TMP, and TEMP environment variables are checked in sequence,
1897  * and if none are set /tmp is returned as the generic Unix default.
1898  *
1899  * NOTE: When possible, use the tempfile() function to create temporary
1900  * files to avoid race conditions on file creation, etc.
1901  *
1902  * @return string
1903  */
1904 function wfTempDir() {
1905         foreach( array( 'TMPDIR', 'TMP', 'TEMP' ) as $var ) {
1906                 $tmp = getenv( $var );
1907                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
1908                         return $tmp;
1909                 }
1910         }
1911         # Hope this is Unix of some kind!
1912         return '/tmp';
1913 }
1914
1915 /**
1916  * Make directory, and make all parent directories if they don't exist
1917  *
1918  * @param string $fullDir Full path to directory to create
1919  * @param int $mode Chmod value to use, default is $wgDirectoryMode
1920  * @return bool
1921  */
1922 function wfMkdirParents( $fullDir, $mode = null ) {
1923         global $wgDirectoryMode;
1924         if( strval( $fullDir ) === '' )
1925                 return true;
1926         if( file_exists( $fullDir ) )
1927                 return true;
1928         // If not defined or isn't an int, set to default
1929         if ( is_null( $mode ) ) {
1930                 $mode = $wgDirectoryMode;
1931         }
1932
1933
1934         # Go back through the paths to find the first directory that exists
1935         $currentDir = $fullDir;
1936         $createList = array();
1937         while ( strval( $currentDir ) !== '' && !file_exists( $currentDir ) ) {
1938                 # Strip trailing slashes
1939                 $currentDir = rtrim( $currentDir, '/\\' );
1940
1941                 # Add to create list
1942                 $createList[] = $currentDir;
1943
1944                 # Find next delimiter searching from the end
1945                 $p = max( strrpos( $currentDir, '/' ), strrpos( $currentDir, '\\' ) );
1946                 if ( $p === false ) {
1947                         $currentDir = false;
1948                 } else {
1949                         $currentDir = substr( $currentDir, 0, $p );
1950                 }
1951         }
1952
1953         if ( count( $createList ) == 0 ) {
1954                 # Directory specified already exists
1955                 return true;
1956         } elseif ( $currentDir === false ) {
1957                 # Went all the way back to root and it apparently doesn't exist
1958                 wfDebugLog( 'mkdir', "Root doesn't exist?\n" );
1959                 return false;
1960         }
1961         # Now go forward creating directories
1962         $createList = array_reverse( $createList );
1963
1964         # Is the parent directory writable?
1965         if ( $currentDir === '' ) {
1966                 $currentDir = '/';
1967         }
1968         if ( !is_writable( $currentDir ) ) {
1969                 wfDebugLog( 'mkdir', "Not writable: $currentDir\n" );
1970                 return false;
1971         }
1972
1973         foreach ( $createList as $dir ) {
1974                 # use chmod to override the umask, as suggested by the PHP manual
1975                 if ( !mkdir( $dir, $mode ) || !chmod( $dir, $mode ) ) {
1976                         wfDebugLog( 'mkdir', "Unable to create directory $dir\n" );
1977                         return false;
1978                 }
1979         }
1980         return true;
1981 }
1982
1983 /**
1984  * Increment a statistics counter
1985  */
1986 function wfIncrStats( $key ) {
1987         global $wgStatsMethod;
1988
1989         if( $wgStatsMethod == 'udp' ) {
1990                 global $wgUDPProfilerHost, $wgUDPProfilerPort, $wgDBname;
1991                 static $socket;
1992                 if (!$socket) {
1993                         $socket=socket_create(AF_INET, SOCK_DGRAM, SOL_UDP);
1994                         $statline="stats/{$wgDBname} - 1 1 1 1 1 -total\n";
1995                         socket_sendto($socket,$statline,strlen($statline),0,$wgUDPProfilerHost,$wgUDPProfilerPort);
1996                 }
1997                 $statline="stats/{$wgDBname} - 1 1 1 1 1 {$key}\n";
1998                 @socket_sendto($socket,$statline,strlen($statline),0,$wgUDPProfilerHost,$wgUDPProfilerPort);
1999         } elseif( $wgStatsMethod == 'cache' ) {
2000                 global $wgMemc;
2001                 $key = wfMemcKey( 'stats', $key );
2002                 if ( is_null( $wgMemc->incr( $key ) ) ) {
2003                         $wgMemc->add( $key, 1 );
2004                 }
2005         } else {
2006                 // Disabled
2007         }
2008 }
2009
2010 /**
2011  * @param mixed $nr The number to format
2012  * @param int $acc The number of digits after the decimal point, default 2
2013  * @param bool $round Whether or not to round the value, default true
2014  * @return float
2015  */
2016 function wfPercent( $nr, $acc = 2, $round = true ) {
2017         $ret = sprintf( "%.${acc}f", $nr );
2018         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2019 }
2020
2021 /**
2022  * Encrypt a username/password.
2023  *
2024  * @param string $userid ID of the user
2025  * @param string $password Password of the user
2026  * @return string Hashed password
2027  * @deprecated Use User::crypt() or User::oldCrypt() instead
2028  */
2029 function wfEncryptPassword( $userid, $password ) {
2030         wfDeprecated(__FUNCTION__);
2031         # Just wrap around User::oldCrypt()
2032         return User::oldCrypt($password, $userid);
2033 }
2034
2035 /**
2036  * Appends to second array if $value differs from that in $default
2037  */
2038 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
2039         if ( is_null( $changed ) ) {
2040                 throw new MWException('GlobalFunctions::wfAppendToArrayIfNotDefault got null');
2041         }
2042         if ( $default[$key] !== $value ) {
2043                 $changed[$key] = $value;
2044         }
2045 }
2046
2047 /**
2048  * Since wfMsg() and co suck, they don't return false if the message key they
2049  * looked up didn't exist but a XHTML string, this function checks for the
2050  * nonexistance of messages by looking at wfMsg() output
2051  *
2052  * @param $msg      The message key looked up
2053  * @param $wfMsgOut The output of wfMsg*()
2054  * @return bool
2055  */
2056 function wfEmptyMsg( $msg, $wfMsgOut ) {
2057         return $wfMsgOut === htmlspecialchars( "<$msg>" );
2058 }
2059
2060 /**
2061  * Find out whether or not a mixed variable exists in a string
2062  *
2063  * @param mixed  needle
2064  * @param string haystack
2065  * @return bool
2066  */
2067 function in_string( $needle, $str ) {
2068         return strpos( $str, $needle ) !== false;
2069 }
2070
2071 function wfSpecialList( $page, $details ) {
2072         global $wgContLang;
2073         $details = $details ? ' ' . $wgContLang->getDirMark() . "($details)" : "";
2074         return $page . $details;
2075 }
2076
2077 /**
2078  * Returns a regular expression of url protocols
2079  *
2080  * @return string
2081  */
2082 function wfUrlProtocols() {
2083         global $wgUrlProtocols;
2084
2085         // Support old-style $wgUrlProtocols strings, for backwards compatibility
2086         // with LocalSettings files from 1.5
2087         if ( is_array( $wgUrlProtocols ) ) {
2088                 $protocols = array();
2089                 foreach ($wgUrlProtocols as $protocol)
2090                         $protocols[] = preg_quote( $protocol, '/' );
2091
2092                 return implode( '|', $protocols );
2093         } else {
2094                 return $wgUrlProtocols;
2095         }
2096 }
2097
2098 /**
2099  * Safety wrapper around ini_get() for boolean settings.
2100  * The values returned from ini_get() are pre-normalized for settings
2101  * set via php.ini or php_flag/php_admin_flag... but *not*
2102  * for those set via php_value/php_admin_value.
2103  *
2104  * It's fairly common for people to use php_value instead of php_flag,
2105  * which can leave you with an 'off' setting giving a false positive
2106  * for code that just takes the ini_get() return value as a boolean.
2107  *
2108  * To make things extra interesting, setting via php_value accepts
2109  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2110  * Unrecognized values go false... again opposite PHP's own coercion
2111  * from string to bool.
2112  *
2113  * Luckily, 'properly' set settings will always come back as '0' or '1',
2114  * so we only have to worry about them and the 'improper' settings.
2115  *
2116  * I frickin' hate PHP... :P
2117  *
2118  * @param string $setting
2119  * @return bool
2120  */
2121 function wfIniGetBool( $setting ) {
2122         $val = ini_get( $setting );
2123         // 'on' and 'true' can't have whitespace around them, but '1' can.
2124         return strtolower( $val ) == 'on'
2125                 || strtolower( $val ) == 'true'
2126                 || strtolower( $val ) == 'yes'
2127                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2128 }
2129
2130 /**
2131  * Execute a shell command, with time and memory limits mirrored from the PHP
2132  * configuration if supported.
2133  * @param $cmd Command line, properly escaped for shell.
2134  * @param &$retval optional, will receive the program's exit code.
2135  *                 (non-zero is usually failure)
2136  * @return collected stdout as a string (trailing newlines stripped)
2137  */
2138 function wfShellExec( $cmd, &$retval=null ) {
2139         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize;
2140
2141         if( wfIniGetBool( 'safe_mode' ) ) {
2142                 wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
2143                 $retval = 1;
2144                 return "Unable to run external programs in safe mode.";
2145         }
2146
2147         if ( php_uname( 's' ) == 'Linux' ) {
2148                 $time = intval( ini_get( 'max_execution_time' ) );
2149                 $mem = intval( $wgMaxShellMemory );
2150                 $filesize = intval( $wgMaxShellFileSize );
2151
2152                 if ( $time > 0 && $mem > 0 ) {
2153                         $script = "$IP/bin/ulimit4.sh";
2154                         if ( is_executable( $script ) ) {
2155                                 $cmd = escapeshellarg( $script ) . " $time $mem $filesize " . escapeshellarg( $cmd );
2156                         }
2157                 }
2158         } elseif ( php_uname( 's' ) == 'Windows NT' ) {
2159                 # This is a hack to work around PHP's flawed invocation of cmd.exe
2160                 # http://news.php.net/php.internals/21796
2161                 $cmd = '"' . $cmd . '"';
2162         }
2163         wfDebug( "wfShellExec: $cmd\n" );
2164
2165         $retval = 1; // error by default?
2166         ob_start();
2167         passthru( $cmd, $retval );
2168         $output = ob_get_contents();
2169         ob_end_clean();
2170
2171         if ( $retval == 127 ) {
2172                 wfDebugLog( 'exec', "Possibly missing executable file: $cmd\n" );
2173         }
2174         return $output;
2175
2176 }
2177
2178 /**
2179  * This function works like "use VERSION" in Perl, the program will die with a
2180  * backtrace if the current version of PHP is less than the version provided
2181  *
2182  * This is useful for extensions which due to their nature are not kept in sync
2183  * with releases, and might depend on other versions of PHP than the main code
2184  *
2185  * Note: PHP might die due to parsing errors in some cases before it ever
2186  *       manages to call this function, such is life
2187  *
2188  * @see perldoc -f use
2189  *
2190  * @param mixed $version The version to check, can be a string, an integer, or
2191  *                       a float
2192  */
2193 function wfUsePHP( $req_ver ) {
2194         $php_ver = PHP_VERSION;
2195
2196         if ( version_compare( $php_ver, (string)$req_ver, '<' ) )
2197                  throw new MWException( "PHP $req_ver required--this is only $php_ver" );
2198 }
2199
2200 /**
2201  * This function works like "use VERSION" in Perl except it checks the version
2202  * of MediaWiki, the program will die with a backtrace if the current version
2203  * of MediaWiki is less than the version provided.
2204  *
2205  * This is useful for extensions which due to their nature are not kept in sync
2206  * with releases
2207  *
2208  * @see perldoc -f use
2209  *
2210  * @param mixed $version The version to check, can be a string, an integer, or
2211  *                       a float
2212  */
2213 function wfUseMW( $req_ver ) {
2214         global $wgVersion;
2215
2216         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) )
2217                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
2218 }
2219
2220 /**
2221  * @deprecated use StringUtils::escapeRegexReplacement
2222  */
2223 function wfRegexReplacement( $string ) {
2224         return StringUtils::escapeRegexReplacement( $string );
2225 }
2226
2227 /**
2228  * Return the final portion of a pathname.
2229  * Reimplemented because PHP5's basename() is buggy with multibyte text.
2230  * http://bugs.php.net/bug.php?id=33898
2231  *
2232  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
2233  * We'll consider it so always, as we don't want \s in our Unix paths either.
2234  *
2235  * @param string $path
2236  * @param string $suffix to remove if present
2237  * @return string
2238  */
2239 function wfBaseName( $path, $suffix='' ) {
2240         $encSuffix = ($suffix == '')
2241                 ? ''
2242                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
2243         $matches = array();
2244         if( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2245                 return $matches[1];
2246         } else {
2247                 return '';
2248         }
2249 }
2250
2251 /**
2252  * Generate a relative path name to the given file.
2253  * May explode on non-matching case-insensitive paths,
2254  * funky symlinks, etc.
2255  *
2256  * @param string $path Absolute destination path including target filename
2257  * @param string $from Absolute source path, directory only
2258  * @return string
2259  */
2260 function wfRelativePath( $path, $from ) {
2261         // Normalize mixed input on Windows...
2262         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2263         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2264
2265         // Trim trailing slashes -- fix for drive root
2266         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2267         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2268
2269         $pieces  = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2270         $against = explode( DIRECTORY_SEPARATOR, $from );
2271
2272         if( $pieces[0] !== $against[0] ) {
2273                 // Non-matching Windows drive letters?
2274                 // Return a full path.
2275                 return $path;
2276         }
2277
2278         // Trim off common prefix
2279         while( count( $pieces ) && count( $against )
2280                 && $pieces[0] == $against[0] ) {
2281                 array_shift( $pieces );
2282                 array_shift( $against );
2283         }
2284
2285         // relative dots to bump us to the parent
2286         while( count( $against ) ) {
2287                 array_unshift( $pieces, '..' );
2288                 array_shift( $against );
2289         }
2290
2291         array_push( $pieces, wfBaseName( $path ) );
2292
2293         return implode( DIRECTORY_SEPARATOR, $pieces );
2294 }
2295
2296 /**
2297  * array_merge() does awful things with "numeric" indexes, including
2298  * string indexes when happen to look like integers. When we want
2299  * to merge arrays with arbitrary string indexes, we don't want our
2300  * arrays to be randomly corrupted just because some of them consist
2301  * of numbers.
2302  *
2303  * Fuck you, PHP. Fuck you in the ear!
2304  *
2305  * @param array $array1, [$array2, [...]]
2306  * @return array
2307  */
2308 function wfArrayMerge( $array1/* ... */ ) {
2309         $out = $array1;
2310         for( $i = 1; $i < func_num_args(); $i++ ) {
2311                 foreach( func_get_arg( $i ) as $key => $value ) {
2312                         $out[$key] = $value;
2313                 }
2314         }
2315         return $out;
2316 }
2317
2318 /**
2319  * Make a URL index, appropriate for the el_index field of externallinks.
2320  */
2321 function wfMakeUrlIndex( $url ) {
2322         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
2323         wfSuppressWarnings();
2324         $bits = parse_url( $url );
2325         wfRestoreWarnings();
2326         if ( !$bits ) {
2327                 return false;
2328         }
2329         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
2330         $delimiter = '';
2331         if ( in_array( $bits['scheme'] . '://' , $wgUrlProtocols ) ) {
2332                 $delimiter = '://';
2333         } elseif ( in_array( $bits['scheme'] .':' , $wgUrlProtocols ) ) {
2334                 $delimiter = ':';
2335                 // parse_url detects for news: and mailto: the host part of an url as path
2336                 // We have to correct this wrong detection
2337                 if ( isset ( $bits['path'] ) ) {
2338                         $bits['host'] = $bits['path'];
2339                         $bits['path'] = '';
2340                 }
2341         } else {
2342                 return false;
2343         }
2344
2345         // Reverse the labels in the hostname, convert to lower case
2346         // For emails reverse domainpart only
2347         if ( $bits['scheme'] == 'mailto' ) {
2348                 $mailparts = explode( '@', $bits['host'], 2 );
2349                 if ( count($mailparts) === 2 ) {
2350                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
2351                 } else {
2352                         // No domain specified, don't mangle it
2353                         $domainpart = '';
2354                 }
2355                 $reversedHost = $domainpart . '@' . $mailparts[0];
2356         } else {
2357                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
2358         }
2359         // Add an extra dot to the end
2360         // Why? Is it in wrong place in mailto links?
2361         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
2362                 $reversedHost .= '.';
2363         }
2364         // Reconstruct the pseudo-URL
2365         $prot = $bits['scheme'];
2366         $index = "$prot$delimiter$reversedHost";
2367         // Leave out user and password. Add the port, path, query and fragment
2368         if ( isset( $bits['port'] ) )      $index .= ':' . $bits['port'];
2369         if ( isset( $bits['path'] ) ) {
2370                 $index .= $bits['path'];
2371         } else {
2372                 $index .= '/';
2373         }
2374         if ( isset( $bits['query'] ) )     $index .= '?' . $bits['query'];
2375         if ( isset( $bits['fragment'] ) )  $index .= '#' . $bits['fragment'];
2376         return $index;
2377 }
2378
2379 /**
2380  * Do any deferred updates and clear the list
2381  * TODO: This could be in Wiki.php if that class made any sense at all
2382  */
2383 function wfDoUpdates()
2384 {
2385         global $wgPostCommitUpdateList, $wgDeferredUpdateList;
2386         foreach ( $wgDeferredUpdateList as $update ) {
2387                 $update->doUpdate();
2388         }
2389         foreach ( $wgPostCommitUpdateList as $update ) {
2390                 $update->doUpdate();
2391         }
2392         $wgDeferredUpdateList = array();
2393         $wgPostCommitUpdateList = array();
2394 }
2395
2396 /**
2397  * @deprecated use StringUtils::explodeMarkup
2398  */
2399 function wfExplodeMarkup( $separator, $text ) {
2400         return StringUtils::explodeMarkup( $separator, $text );
2401 }
2402
2403 /**
2404  * Convert an arbitrarily-long digit string from one numeric base
2405  * to another, optionally zero-padding to a minimum column width.
2406  *
2407  * Supports base 2 through 36; digit values 10-36 are represented
2408  * as lowercase letters a-z. Input is case-insensitive.
2409  *
2410  * @param $input string of digits
2411  * @param $sourceBase int 2-36
2412  * @param $destBase int 2-36
2413  * @param $pad int 1 or greater
2414  * @param $lowercase bool
2415  * @return string or false on invalid input
2416  */
2417 function wfBaseConvert( $input, $sourceBase, $destBase, $pad=1, $lowercase=true ) {
2418         $input = strval( $input );
2419         if( $sourceBase < 2 ||
2420                 $sourceBase > 36 ||
2421                 $destBase < 2 ||
2422                 $destBase > 36 ||
2423                 $pad < 1 ||
2424                 $sourceBase != intval( $sourceBase ) ||
2425                 $destBase != intval( $destBase ) ||
2426                 $pad != intval( $pad ) ||
2427                 !is_string( $input ) ||
2428                 $input == '' ) {
2429                 return false;
2430         }
2431         $digitChars = ( $lowercase ) ?  '0123456789abcdefghijklmnopqrstuvwxyz' : '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
2432         $inDigits = array();
2433         $outChars = '';
2434
2435         // Decode and validate input string
2436         $input = strtolower( $input );
2437         for( $i = 0; $i < strlen( $input ); $i++ ) {
2438                 $n = strpos( $digitChars, $input{$i} );
2439                 if( $n === false || $n > $sourceBase ) {
2440                         return false;
2441                 }
2442                 $inDigits[] = $n;
2443         }
2444
2445         // Iterate over the input, modulo-ing out an output digit
2446         // at a time until input is gone.
2447         while( count( $inDigits ) ) {
2448                 $work = 0;
2449                 $workDigits = array();
2450
2451                 // Long division...
2452                 foreach( $inDigits as $digit ) {
2453                         $work *= $sourceBase;
2454                         $work += $digit;
2455
2456                         if( $work < $destBase ) {
2457                                 // Gonna need to pull another digit.
2458                                 if( count( $workDigits ) ) {
2459                                         // Avoid zero-padding; this lets us find
2460                                         // the end of the input very easily when
2461                                         // length drops to zero.
2462                                         $workDigits[] = 0;
2463                                 }
2464                         } else {
2465                                 // Finally! Actual division!
2466                                 $workDigits[] = intval( $work / $destBase );
2467
2468                                 // Isn't it annoying that most programming languages
2469                                 // don't have a single divide-and-remainder operator,
2470                                 // even though the CPU implements it that way?
2471                                 $work = $work % $destBase;
2472                         }
2473                 }
2474
2475                 // All that division leaves us with a remainder,
2476                 // which is conveniently our next output digit.
2477                 $outChars .= $digitChars[$work];
2478
2479                 // And we continue!
2480                 $inDigits = $workDigits;
2481         }
2482
2483         while( strlen( $outChars ) < $pad ) {
2484                 $outChars .= '0';
2485         }
2486
2487         return strrev( $outChars );
2488 }
2489
2490 /**
2491  * Create an object with a given name and an array of construct parameters
2492  * @param string $name
2493  * @param array $p parameters
2494  */
2495 function wfCreateObject( $name, $p ){
2496         $p = array_values( $p );
2497         switch ( count( $p ) ) {
2498                 case 0:
2499                         return new $name;
2500                 case 1:
2501                         return new $name( $p[0] );
2502                 case 2:
2503                         return new $name( $p[0], $p[1] );
2504                 case 3:
2505                         return new $name( $p[0], $p[1], $p[2] );
2506                 case 4:
2507                         return new $name( $p[0], $p[1], $p[2], $p[3] );
2508                 case 5:
2509                         return new $name( $p[0], $p[1], $p[2], $p[3], $p[4] );
2510                 case 6:
2511                         return new $name( $p[0], $p[1], $p[2], $p[3], $p[4], $p[5] );
2512                 default:
2513                         throw new MWException( "Too many arguments to construtor in wfCreateObject" );
2514         }
2515 }
2516
2517 /**
2518  * Alias for modularized function
2519  * @deprecated Use Http::get() instead
2520  */
2521 function wfGetHTTP( $url, $timeout = 'default' ) {
2522         wfDeprecated(__FUNCTION__);
2523         return Http::get( $url, $timeout );
2524 }
2525
2526 /**
2527  * Alias for modularized function
2528  * @deprecated Use Http::isLocalURL() instead
2529  */
2530 function wfIsLocalURL( $url ) {
2531         wfDeprecated(__FUNCTION__);
2532         return Http::isLocalURL( $url );
2533 }
2534
2535 function wfHttpOnlySafe() {
2536         global $wgHttpOnlyBlacklist;
2537         if( !version_compare("5.2", PHP_VERSION, "<") )
2538                 return false;
2539
2540         if( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
2541                 foreach( $wgHttpOnlyBlacklist as $regex ) {
2542                         if( preg_match( $regex, $_SERVER['HTTP_USER_AGENT'] ) ) {
2543                                 return false;
2544                         }
2545                 }
2546         }
2547
2548         return true;
2549 }
2550
2551 /**
2552  * Initialise php session
2553  */
2554 function wfSetupSession() {
2555         global $wgSessionsInMemcached, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $wgCookieHttpOnly;
2556         if( $wgSessionsInMemcached ) {
2557                 require_once( 'MemcachedSessions.php' );
2558         } elseif( 'files' != ini_get( 'session.save_handler' ) ) {
2559                 # If it's left on 'user' or another setting from another
2560                 # application, it will end up failing. Try to recover.
2561                 ini_set ( 'session.save_handler', 'files' );
2562         }
2563         $httpOnlySafe = wfHttpOnlySafe();
2564         wfDebugLog( 'cookie',
2565                 'session_set_cookie_params: "' . implode( '", "',
2566                         array(
2567                                 0,
2568                                 $wgCookiePath,
2569                                 $wgCookieDomain,
2570                                 $wgCookieSecure,
2571                                 $httpOnlySafe && $wgCookieHttpOnly ) ) . '"' );
2572         if( $httpOnlySafe && $wgCookieHttpOnly ) {
2573                 session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $wgCookieHttpOnly );
2574         } else {
2575                 // PHP 5.1 throws warnings if you pass the HttpOnly parameter for 5.2.
2576                 session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure );
2577         }
2578         session_cache_limiter( 'private, must-revalidate' );
2579         wfSuppressWarnings();
2580         session_start();
2581         wfRestoreWarnings();
2582 }
2583
2584 /**
2585  * Get an object from the precompiled serialized directory
2586  *
2587  * @return mixed The variable on success, false on failure
2588  */
2589 function wfGetPrecompiledData( $name ) {
2590         global $IP;
2591
2592         $file = "$IP/serialized/$name";
2593         if ( file_exists( $file ) ) {
2594                 $blob = file_get_contents( $file );
2595                 if ( $blob ) {
2596                         return unserialize( $blob );
2597                 }
2598         }
2599         return false;
2600 }
2601
2602 function wfGetCaller( $level = 2 ) {
2603         $backtrace = wfDebugBacktrace();
2604         if ( isset( $backtrace[$level] ) ) {
2605                 return wfFormatStackFrame($backtrace[$level]);
2606         } else {
2607                 $caller = 'unknown';
2608         }
2609         return $caller;
2610 }
2611
2612 /** Return a string consisting all callers in stack, somewhat useful sometimes for profiling specific points */
2613 function wfGetAllCallers() {
2614         return implode('/', array_map('wfFormatStackFrame',array_reverse(wfDebugBacktrace())));
2615 }
2616
2617 /** Return a string representation of frame */
2618 function wfFormatStackFrame($frame) {
2619         return isset( $frame["class"] )?
2620                 $frame["class"]."::".$frame["function"]:
2621                 $frame["function"];
2622 }
2623
2624 /**
2625  * Get a cache key
2626  */
2627 function wfMemcKey( /*... */ ) {
2628         $args = func_get_args();
2629         $key = wfWikiID() . ':' . implode( ':', $args );
2630         return $key;
2631 }
2632
2633 /**
2634  * Get a cache key for a foreign DB
2635  */
2636 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
2637         $args = array_slice( func_get_args(), 2 );
2638         if ( $prefix ) {
2639                 $key = "$db-$prefix:" . implode( ':', $args );
2640         } else {
2641                 $key = $db . ':' . implode( ':', $args );
2642         }
2643         return $key;
2644 }
2645
2646 /**
2647  * Get an ASCII string identifying this wiki
2648  * This is used as a prefix in memcached keys
2649  */
2650 function wfWikiID( $db = null ) {
2651         if( $db instanceof Database ) {
2652                 return $db->getWikiID();
2653         } else {
2654         global $wgDBprefix, $wgDBname;
2655                 if ( $wgDBprefix ) {
2656                         return "$wgDBname-$wgDBprefix";
2657                 } else {
2658                         return $wgDBname;
2659                 }
2660         }
2661 }
2662
2663 /**
2664  * Split a wiki ID into DB name and table prefix
2665  */
2666 function wfSplitWikiID( $wiki ) {
2667         $bits = explode( '-', $wiki, 2 );
2668         if ( count( $bits ) < 2 ) {
2669                 $bits[] = '';
2670         }
2671         return $bits;
2672 }
2673
2674 /*
2675  * Get a Database object.
2676  * @param integer $db Index of the connection to get. May be DB_MASTER for the
2677  *                master (for write queries), DB_SLAVE for potentially lagged
2678  *                read queries, or an integer >= 0 for a particular server.
2679  *
2680  * @param mixed $groups Query groups. An array of group names that this query
2681  *              belongs to. May contain a single string if the query is only
2682  *              in one group.
2683  *
2684  * @param string $wiki The wiki ID, or false for the current wiki
2685  *
2686  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
2687  * will always return the same object, unless the underlying connection or load
2688  * balancer is manually destroyed.
2689  */
2690 function &wfGetDB( $db, $groups = array(), $wiki = false ) {
2691         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
2692 }
2693
2694 /**
2695  * Get a load balancer object.
2696  *
2697  * @param array $groups List of query groups
2698  * @param string $wiki Wiki ID, or false for the current wiki
2699  * @return LoadBalancer
2700  */
2701 function wfGetLB( $wiki = false ) {
2702         return wfGetLBFactory()->getMainLB( $wiki );
2703 }
2704
2705 /**
2706  * Get the load balancer factory object
2707  */
2708 function &wfGetLBFactory() {
2709         return LBFactory::singleton();
2710 }
2711
2712 /**
2713  * Find a file.
2714  * Shortcut for RepoGroup::singleton()->findFile()
2715  * @param mixed $title Title object or string. May be interwiki.
2716  * @param mixed $time Requested time for an archived image, or false for the
2717  *                    current version. An image object will be returned which
2718  *                    was created at the specified time.
2719  * @param mixed $flags FileRepo::FIND_ flags
2720  * @return File, or false if the file does not exist
2721  */
2722 function wfFindFile( $title, $time = false, $flags = 0 ) {
2723         return RepoGroup::singleton()->findFile( $title, $time, $flags );
2724 }
2725
2726 /**
2727  * Get an object referring to a locally registered file.
2728  * Returns a valid placeholder object if the file does not exist.
2729  */
2730 function wfLocalFile( $title ) {
2731         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
2732 }
2733
2734 /**
2735  * Should low-performance queries be disabled?
2736  *
2737  * @return bool
2738  */
2739 function wfQueriesMustScale() {
2740         global $wgMiserMode;
2741         return $wgMiserMode
2742                 || ( SiteStats::pages() > 100000
2743                 && SiteStats::edits() > 1000000
2744                 && SiteStats::users() > 10000 );
2745 }
2746
2747 /**
2748  * Get the path to a specified script file, respecting file
2749  * extensions; this is a wrapper around $wgScriptExtension etc.
2750  *
2751  * @param string $script Script filename, sans extension
2752  * @return string
2753  */
2754 function wfScript( $script = 'index' ) {
2755         global $wgScriptPath, $wgScriptExtension;
2756         return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
2757 }
2758
2759 /**
2760  * Convenience function converts boolean values into "true"
2761  * or "false" (string) values
2762  *
2763  * @param bool $value
2764  * @return string
2765  */
2766 function wfBoolToStr( $value ) {
2767         return $value ? 'true' : 'false';
2768 }
2769
2770 /**
2771  * Load an extension messages file
2772  *
2773  * @param string $extensionName Name of extension to load messages from\for.
2774  * @param string $langcode Language to load messages for, or false for default
2775  *                         behvaiour (en, content language and user language).
2776  * @since r24808 (v1.11) Using this method of loading extension messages will not work
2777  * on MediaWiki prior to that
2778  */
2779 function wfLoadExtensionMessages( $extensionName, $langcode = false ) {
2780         global $wgExtensionMessagesFiles, $wgMessageCache, $wgLang, $wgContLang;
2781
2782         #For recording whether extension message files have been loaded in a given language.
2783         static $loaded = array();
2784
2785         if( !array_key_exists( $extensionName, $loaded ) ) {
2786                 $loaded[$extensionName] = array();
2787         }
2788
2789         if ( !isset($wgExtensionMessagesFiles[$extensionName]) ) {
2790                 throw new MWException( "Messages file for extensions $extensionName is not defined" );
2791         }
2792
2793         if( !$langcode && !array_key_exists( '*', $loaded[$extensionName] ) ) {
2794                 # Just do en, content language and user language.
2795                 $wgMessageCache->loadMessagesFile( $wgExtensionMessagesFiles[$extensionName], false );
2796                 # Mark that they have been loaded.
2797                 $loaded[$extensionName]['en'] = true;
2798                 $loaded[$extensionName][$wgLang->getCode()] = true;
2799                 $loaded[$extensionName][$wgContLang->getCode()] = true;
2800                 # Mark that this part has been done to avoid weird if statements.
2801                 $loaded[$extensionName]['*'] = true;
2802         } elseif( is_string( $langcode ) && !array_key_exists( $langcode, $loaded[$extensionName] ) ) {
2803                 # Load messages for specified language.
2804                 $wgMessageCache->loadMessagesFile( $wgExtensionMessagesFiles[$extensionName], $langcode );
2805                 # Mark that they have been loaded.
2806                 $loaded[$extensionName][$langcode] = true;
2807         }
2808 }
2809
2810 /**
2811  * Get a platform-independent path to the null file, e.g.
2812  * /dev/null
2813  *
2814  * @return string
2815  */
2816 function wfGetNull() {
2817         return wfIsWindows()
2818                 ? 'NUL'
2819                 : '/dev/null';
2820 }
2821
2822 /**
2823  * Displays a maxlag error
2824  *
2825  * @param string $host Server that lags the most
2826  * @param int $lag Maxlag (actual)
2827  * @param int $maxLag Maxlag (requested)
2828  */
2829 function wfMaxlagError( $host, $lag, $maxLag ) {
2830         global $wgShowHostnames;
2831         header( 'HTTP/1.1 503 Service Unavailable' );
2832         header( 'Retry-After: ' . max( intval( $maxLag ), 5 ) );
2833         header( 'X-Database-Lag: ' . intval( $lag ) );
2834         header( 'Content-Type: text/plain' );
2835         if( $wgShowHostnames ) {
2836                 echo "Waiting for $host: $lag seconds lagged\n";
2837         } else {
2838                 echo "Waiting for a database server: $lag seconds lagged\n";
2839         }
2840 }
2841
2842 /**
2843  * Throws an E_USER_NOTICE saying that $function is deprecated
2844  * @param string $function
2845  * @return null
2846  */
2847 function wfDeprecated( $function ) {
2848         global $wgDebugLogFile;
2849         if ( !$wgDebugLogFile ) {
2850                 return;
2851         }
2852         $callers = wfDebugBacktrace();
2853         if( isset( $callers[2] ) ){
2854                 $callerfunc = $callers[2];
2855                 $callerfile = $callers[1];
2856                 if( isset( $callerfile['file'] ) && isset( $callerfile['line'] ) ){
2857                         $file = $callerfile['file'] . ' at line ' . $callerfile['line'];
2858                 } else {
2859                         $file = '(internal function)';
2860                 }
2861                 $func = '';
2862                 if( isset( $callerfunc['class'] ) )
2863                         $func .= $callerfunc['class'] . '::';
2864                 $func .= @$callerfunc['function'];
2865                 $msg = "Use of $function is deprecated. Called from $func in $file";
2866         } else {
2867                 $msg = "Use of $function is deprecated.";
2868         }
2869         wfDebug( "$msg\n" );
2870 }
2871
2872 /**
2873  * Sleep until the worst slave's replication lag is less than or equal to
2874  * $maxLag, in seconds.  Use this when updating very large numbers of rows, as
2875  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
2876  * a no-op if there are no slaves.
2877  *
2878  * Every time the function has to wait for a slave, it will print a message to
2879  * that effect (and then sleep for a little while), so it's probably not best
2880  * to use this outside maintenance scripts in its present form.
2881  *
2882  * @param int $maxLag
2883  * @return null
2884  */
2885 function wfWaitForSlaves( $maxLag ) {
2886         if( $maxLag ) {
2887                 $lb = wfGetLB();
2888                 list( $host, $lag ) = $lb->getMaxLag();
2889                 while( $lag > $maxLag ) {
2890                         $name = @gethostbyaddr( $host );
2891                         if( $name !== false ) {
2892                                 $host = $name;
2893                         }
2894                         print "Waiting for $host (lagged $lag seconds)...\n";
2895                         sleep($maxLag);
2896                         list( $host, $lag ) = $lb->getMaxLag();
2897                 }
2898         }
2899 }
2900
2901 /** Generate a random 32-character hexadecimal token.
2902  * @param mixed $salt Some sort of salt, if necessary, to add to random characters before hashing.
2903  */
2904 function wfGenerateToken( $salt = '' ) {
2905         $salt = serialize($salt);
2906
2907         return md5( mt_rand( 0, 0x7fffffff ) . $salt );
2908 }
2909
2910 /**
2911  * Replace all invalid characters with -
2912  * @param mixed $title Filename to process
2913  */
2914 function wfStripIllegalFilenameChars( $name ) {
2915         $name = wfBaseName( $name );
2916         $name = preg_replace ( "/[^".Title::legalChars()."]|:/", '-', $name );
2917         return $name;
2918 }