includes/GlobalFunctions.php

   1 <?php
   2 /**
   3  * Global functions used everywhere
   4  * @file
   5  */
   6
   7 if ( !defined( 'MEDIAWIKI' ) ) {
   8         die( "This file is part of MediaWiki, it is not a valid entry point" );
   9 }
  10
  11 // Hide compatibility functions from Doxygen
  12 /// @cond
  13
  14 /**
  15  * Compatibility functions
  16  *
  17  * We support PHP 5.2.3 and up.
  18  * Re-implementations of newer functions or functions in non-standard
  19  * PHP extensions may be included here.
  20  */
  21
  22 if( !function_exists( 'iconv' ) ) {
  23         /** @codeCoverageIgnore */
  24         function iconv( $from, $to, $string ) {
  25                 return Fallback::iconv( $from, $to, $string );
  26         }
  27 }
  28
  29 if ( !function_exists( 'mb_substr' ) ) {
  30         /** @codeCoverageIgnore */
  31         function mb_substr( $str, $start, $count='end' ) {
  32                 return Fallback::mb_substr( $str, $start, $count );
  33         }
  34
  35         /** @codeCoverageIgnore */
  36         function mb_substr_split_unicode( $str, $splitPos ) {
  37                 return Fallback::mb_substr_split_unicode( $str, $splitPos );
  38         }
  39 }
  40
  41 if ( !function_exists( 'mb_strlen' ) ) {
  42         /** @codeCoverageIgnore */
  43         function mb_strlen( $str, $enc = '' ) {
  44                 return Fallback::mb_strlen( $str, $enc );
  45         }
  46 }
  47
  48 if( !function_exists( 'mb_strpos' ) ) {
  49         /** @codeCoverageIgnore */
  50         function mb_strpos( $haystack, $needle, $offset = 0, $encoding = '' ) {
  51                 return Fallback::mb_strpos( $haystack, $needle, $offset, $encoding );
  52         }
  53
  54 }
  55
  56 if( !function_exists( 'mb_strrpos' ) ) {
  57         /** @codeCoverageIgnore */
  58         function mb_strrpos( $haystack, $needle, $offset = 0, $encoding = '' ) {
  59                 return Fallback::mb_strrpos( $haystack, $needle, $offset, $encoding );
  60         }
  61 }
  62
  63
  64 // Support for Wietse Venema's taint feature
  65 if ( !function_exists( 'istainted' ) ) {
  66         /** @codeCoverageIgnore */
  67         function istainted( $var ) {
  68                 return 0;
  69         }
  70         /** @codeCoverageIgnore */
  71         function taint( $var, $level = 0 ) {}
  72         /** @codeCoverageIgnore */
  73         function untaint( $var, $level = 0 ) {}
  74         define( 'TC_HTML', 1 );
  75         define( 'TC_SHELL', 1 );
  76         define( 'TC_MYSQL', 1 );
  77         define( 'TC_PCRE', 1 );
  78         define( 'TC_SELF', 1 );
  79 }
  80 /// @endcond
  81
  82 /**
  83  * Like array_diff( $a, $b ) except that it works with two-dimensional arrays.
  84  */
  85 function wfArrayDiff2( $a, $b ) {
  86         return array_udiff( $a, $b, 'wfArrayDiff2_cmp' );
  87 }
  88
  89 /**
  90  * @param $a
  91  * @param $b
  92  * @return int
  93  */
  94 function wfArrayDiff2_cmp( $a, $b ) {
  95         if ( !is_array( $a ) ) {
  96                 return strcmp( $a, $b );
  97         } elseif ( count( $a ) !== count( $b ) ) {
  98                 return count( $a ) < count( $b ) ? -1 : 1;
  99         } else {
 100                 reset( $a );
 101                 reset( $b );
 102                 while( ( list( , $valueA ) = each( $a ) ) && ( list( , $valueB ) = each( $b ) ) ) {
 103                         $cmp = strcmp( $valueA, $valueB );
 104                         if ( $cmp !== 0 ) {
 105                                 return $cmp;
 106                         }
 107                 }
 108                 return 0;
 109         }
 110 }
 111
 112 /**
 113  * Array lookup
 114  * Returns an array where the values in the first array are replaced by the
 115  * values in the second array with the corresponding keys
 116  *
 117  * @param $a Array
 118  * @param $b Array
 119  * @return array
 120  */
 121 function wfArrayLookup( $a, $b ) {
 122         return array_flip( array_intersect( array_flip( $a ), array_keys( $b ) ) );
 123 }
 124
 125 /**
 126  * Appends to second array if $value differs from that in $default
 127  *
 128  * @param $key String|Int
 129  * @param $value Mixed
 130  * @param $default Mixed
 131  * @param $changed Array to alter
 132  */
 133 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
 134         if ( is_null( $changed ) ) {
 135                 throw new MWException( 'GlobalFunctions::wfAppendToArrayIfNotDefault got null' );
 136         }
 137         if ( $default[$key] !== $value ) {
 138                 $changed[$key] = $value;
 139         }
 140 }
 141
 142 /**
 143  * Backwards array plus for people who haven't bothered to read the PHP manual
 144  * XXX: will not darn your socks for you.
 145  *
 146  * @param $array1 Array
 147  * @param [$array2, [...]] Arrays
 148  * @return Array
 149  */
 150 function wfArrayMerge( $array1/* ... */ ) {
 151         $args = func_get_args();
 152         $args = array_reverse( $args, true );
 153         $out = array();
 154         foreach ( $args as $arg ) {
 155                 $out += $arg;
 156         }
 157         return $out;
 158 }
 159
 160 /**
 161  * Merge arrays in the style of getUserPermissionsErrors, with duplicate removal
 162  * e.g.
 163  *      wfMergeErrorArrays(
 164  *              array( array( 'x' ) ),
 165  *              array( array( 'x', '2' ) ),
 166  *              array( array( 'x' ) ),
 167  *              array( array( 'y') )
 168  *      );
 169  * returns:
 170  *              array(
 171  *              array( 'x', '2' ),
 172  *              array( 'x' ),
 173  *              array( 'y' )
 174  *      )
 175  * @param varargs
 176  * @return Array
 177  */
 178 function wfMergeErrorArrays( /*...*/ ) {
 179         $args = func_get_args();
 180         $out = array();
 181         foreach ( $args as $errors ) {
 182                 foreach ( $errors as $params ) {
 183                         # @todo FIXME: Sometimes get nested arrays for $params,
 184                         # which leads to E_NOTICEs
 185                         $spec = implode( "\t", $params );
 186                         $out[$spec] = $params;
 187                 }
 188         }
 189         return array_values( $out );
 190 }
 191
 192 /**
 193  * Insert array into another array after the specified *KEY*
 194  *
 195  * @param $array Array: The array.
 196  * @param $insert Array: The array to insert.
 197  * @param $after Mixed: The key to insert after
 198  * @return Array
 199  */
 200 function wfArrayInsertAfter( $array, $insert, $after ) {
 201         // Find the offset of the element to insert after.
 202         $keys = array_keys( $array );
 203         $offsetByKey = array_flip( $keys );
 204
 205         $offset = $offsetByKey[$after];
 206
 207         // Insert at the specified offset
 208         $before = array_slice( $array, 0, $offset + 1, true );
 209         $after = array_slice( $array, $offset + 1, count( $array ) - $offset, true );
 210
 211         $output = $before + $insert + $after;
 212
 213         return $output;
 214 }
 215
 216 /**
 217  * Recursively converts the parameter (an object) to an array with the same data
 218  *
 219  * @param $objOrArray Object|Array
 220  * @param $recursive Bool
 221  * @return Array
 222  */
 223 function wfObjectToArray( $objOrArray, $recursive = true ) {
 224         $array = array();
 225         if( is_object( $objOrArray ) ) {
 226                 $objOrArray = get_object_vars( $objOrArray );
 227         }
 228         foreach ( $objOrArray as $key => $value ) {
 229                 if ( $recursive && ( is_object( $value ) || is_array( $value ) ) ) {
 230                         $value = wfObjectToArray( $value );
 231                 }
 232
 233                 $array[$key] = $value;
 234         }
 235
 236         return $array;
 237 }
 238
 239 /**
 240  * Wrapper around array_map() which also taints variables
 241  *
 242  * @param  $function Callback
 243  * @param  $input Array
 244  * @return Array
 245  */
 246 function wfArrayMap( $function, $input ) {
 247         $ret = array_map( $function, $input );
 248         foreach ( $ret as $key => $value ) {
 249                 $taint = istainted( $input[$key] );
 250                 if ( $taint ) {
 251                         taint( $ret[$key], $taint );
 252                 }
 253         }
 254         return $ret;
 255 }
 256
 257 /**
 258  * Get a random decimal value between 0 and 1, in a way
 259  * not likely to give duplicate values for any realistic
 260  * number of articles.
 261  *
 262  * @return string
 263  */
 264 function wfRandom() {
 265         # The maximum random value is "only" 2^31-1, so get two random
 266         # values to reduce the chance of dupes
 267         $max = mt_getrandmax() + 1;
 268         $rand = number_format( ( mt_rand() * $max + mt_rand() )
 269                 / $max / $max, 12, '.', '' );
 270         return $rand;
 271 }
 272
 273 /**
 274  * We want some things to be included as literal characters in our title URLs
 275  * for prettiness, which urlencode encodes by default.  According to RFC 1738,
 276  * all of the following should be safe:
 277  *
 278  * ;:@&=$-_.+!*'(),
 279  *
 280  * But + is not safe because it's used to indicate a space; &= are only safe in
 281  * paths and not in queries (and we don't distinguish here); ' seems kind of
 282  * scary; and urlencode() doesn't touch -_. to begin with.  Plus, although /
 283  * is reserved, we don't care.  So the list we unescape is:
 284  *
 285  * ;:@$!*(),/
 286  *
 287  * However, IIS7 redirects fail when the url contains a colon (Bug 22709),
 288  * so no fancy : for IIS7.
 289  *
 290  * %2F in the page titles seems to fatally break for some reason.
 291  *
 292  * @param $s String:
 293  * @return string
 294 */
 295 function wfUrlencode( $s ) {
 296         static $needle;
 297         if ( is_null( $s ) ) {
 298                 $needle = null;
 299                 return;
 300         }
 301
 302         if ( is_null( $needle ) ) {
 303                 $needle = array( '%3B', '%40', '%24', '%21', '%2A', '%28', '%29', '%2C', '%2F' );
 304                 if ( !isset( $_SERVER['SERVER_SOFTWARE'] ) || ( strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/7' ) === false ) ) {
 305                         $needle[] = '%3A';
 306                 }
 307         }
 308
 309         $s = urlencode( $s );
 310         $s = str_ireplace(
 311                 $needle,
 312                 array( ';', '@', '$', '!', '*', '(', ')', ',', '/', ':' ),
 313                 $s
 314         );
 315
 316         return $s;
 317 }
 318
 319 /**
 320  * This function takes two arrays as input, and returns a CGI-style string, e.g.
 321  * "days=7&limit=100". Options in the first array override options in the second.
 322  * Options set to "" will not be output.
 323  *
 324  * @param $array1 Array ( String|Array )
 325  * @param $array2 Array ( String|Array )
 326  * @param $prefix String
 327  * @return String
 328  */
 329 function wfArrayToCGI( $array1, $array2 = null, $prefix = '' ) {
 330         if ( !is_null( $array2 ) ) {
 331                 $array1 = $array1 + $array2;
 332         }
 333
 334         $cgi = '';
 335         foreach ( $array1 as $key => $value ) {
 336                 if ( $value !== '' ) {
 337                         if ( $cgi != '' ) {
 338                                 $cgi .= '&';
 339                         }
 340                         if ( $prefix !== '' ) {
 341                                 $key = $prefix . "[$key]";
 342                         }
 343                         if ( is_array( $value ) ) {
 344                                 $firstTime = true;
 345                                 foreach ( $value as $k => $v ) {
 346                                         $cgi .= $firstTime ? '' : '&';
 347                                         if ( is_array( $v ) ) {
 348                                                 $cgi .= wfArrayToCGI( $v, null, $key . "[$k]" );
 349                                         } else {
 350                                                 $cgi .= urlencode( $key . "[$k]" ) . '=' . urlencode( $v );
 351                                         }
 352                                         $firstTime = false;
 353                                 }
 354                         } else {
 355                                 if ( is_object( $value ) ) {
 356                                         $value = $value->__toString();
 357                                 }
 358                                 $cgi .= urlencode( $key ) . '=' . urlencode( $value );
 359                         }
 360                 }
 361         }
 362         return $cgi;
 363 }
 364
 365 /**
 366  * This is the logical opposite of wfArrayToCGI(): it accepts a query string as
 367  * its argument and returns the same string in array form.  This allows compa-
 368  * tibility with legacy functions that accept raw query strings instead of nice
 369  * arrays.  Of course, keys and values are urldecode()d.  Don't try passing in-
 370  * valid query strings, or it will explode.
 371  *
 372  * @param $query String: query string
 373  * @return array Array version of input
 374  */
 375 function wfCgiToArray( $query ) {
 376         if ( isset( $query[0] ) && $query[0] == '?' ) {
 377                 $query = substr( $query, 1 );
 378         }
 379         $bits = explode( '&', $query );
 380         $ret = array();
 381         foreach ( $bits as $bit ) {
 382                 if ( $bit === '' ) {
 383                         continue;
 384                 }
 385                 list( $key, $value ) = explode( '=', $bit );
 386                 $key = urldecode( $key );
 387                 $value = urldecode( $value );
 388                 if ( strpos( $key, '[' ) !== false ) {
 389                         $keys = array_reverse( explode( '[', $key ) );
 390                         $key = array_pop( $keys );
 391                         $temp = $value;
 392                         foreach ( $keys as $k ) {
 393                                 $k = substr( $k, 0, -1 );
 394                                 $temp = array( $k => $temp );
 395                         }
 396                         if ( isset( $ret[$key] ) ) {
 397                                 $ret[$key] = array_merge( $ret[$key], $temp );
 398                         } else {
 399                                 $ret[$key] = $temp;
 400                         }
 401                 } else {
 402                         $ret[$key] = $value;
 403                 }
 404         }
 405         return $ret;
 406 }
 407
 408 /**
 409  * Append a query string to an existing URL, which may or may not already
 410  * have query string parameters already. If so, they will be combined.
 411  *
 412  * @param $url String
 413  * @param $query Mixed: string or associative array
 414  * @return string
 415  */
 416 function wfAppendQuery( $url, $query ) {
 417         if ( is_array( $query ) ) {
 418                 $query = wfArrayToCGI( $query );
 419         }
 420         if( $query != '' ) {
 421                 if( false === strpos( $url, '?' ) ) {
 422                         $url .= '?';
 423                 } else {
 424                         $url .= '&';
 425                 }
 426                 $url .= $query;
 427         }
 428         return $url;
 429 }
 430
 431 /**
 432  * Expand a potentially local URL to a fully-qualified URL.  Assumes $wgServer
 433  * is correct.
 434  *
 435  * The meaning of the PROTO_* constants is as follows:
 436  * PROTO_HTTP: Output a URL starting with http://
 437  * PROTO_HTTPS: Output a URL starting with https://
 438  * PROTO_RELATIVE: Output a URL starting with // (protocol-relative URL)
 439  * PROTO_CURRENT: Output a URL starting with either http:// or https:// , depending on which protocol was used for the current incoming request
 440  *
 441  * @todo this won't work with current-path-relative URLs
 442  * like "subdir/foo.html", etc.
 443  *
 444  * @param $url String: either fully-qualified or a local path + query
 445  * @param $defaultProto Mixed: one of the PROTO_* constants. Determines the protocol to use if $url or $wgServer is protocol-relative
 446  * @return string Fully-qualified URL
 447  */
 448 function wfExpandUrl( $url, $defaultProto = PROTO_CURRENT ) {
 449         global $wgServer;
 450         if ( $defaultProto === PROTO_CURRENT ) {
 451                 $defaultProto = WebRequest::detectProtocol() . '://';
 452         }
 453
 454         // Analyze $wgServer to obtain its protocol
 455         $bits = wfParseUrl( $wgServer );
 456         $serverHasProto = $bits && $bits['scheme'] != '';
 457         $defaultProtoWithoutSlashes = substr( $defaultProto, 0, -2 );
 458
 459         if( substr( $url, 0, 2 ) == '//' ) {
 460                 return $defaultProtoWithoutSlashes . $url;
 461         } elseif( substr( $url, 0, 1 ) == '/' ) {
 462                 // If $wgServer is protocol-relative, prepend $defaultProtoWithoutSlashes, otherwise leave it alone
 463                 return ( $serverHasProto ? '' : $defaultProtoWithoutSlashes ) . $wgServer . $url;
 464         } else {
 465                 return $url;
 466         }
 467 }
 468
 469 /**
 470  * Returns a regular expression of url protocols
 471  *
 472  * @return String
 473  */
 474 function wfUrlProtocols() {
 475         global $wgUrlProtocols;
 476
 477         static $retval = null;
 478         if ( !is_null( $retval ) ) {
 479                 return $retval;
 480         }
 481
 482         // Support old-style $wgUrlProtocols strings, for backwards compatibility
 483         // with LocalSettings files from 1.5
 484         if ( is_array( $wgUrlProtocols ) ) {
 485                 $protocols = array();
 486                 foreach ( $wgUrlProtocols as $protocol ) {
 487                         $protocols[] = preg_quote( $protocol, '/' );
 488                 }
 489
 490                 $retval = implode( '|', $protocols );
 491         } else {
 492                 $retval = $wgUrlProtocols;
 493         }
 494         return $retval;
 495 }
 496
 497 /**
 498  * parse_url() work-alike, but non-broken.  Differences:
 499  *
 500  * 1) Does not raise warnings on bad URLs (just returns false)
 501  * 2) Handles protocols that don't use :// (e.g., mailto: and news: , as well as protocol-relative URLs) correctly
 502  * 3) Adds a "delimiter" element to the array, either '://', ':' or '//' (see (2))
 503  *
 504  * @param $url String: a URL to parse
 505  * @return Array: bits of the URL in an associative array, per PHP docs
 506  */
 507 function wfParseUrl( $url ) {
 508         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
 509
 510         // Protocol-relative URLs are handled really badly by parse_url(). It's so bad that the easiest
 511         // way to handle them is to just prepend 'http:' and strip the protocol out later
 512         $wasRelative = substr( $url, 0, 2 ) == '//';
 513         if ( $wasRelative ) {
 514                 $url = "http:$url";
 515         }
 516         wfSuppressWarnings();
 517         $bits = parse_url( $url );
 518         wfRestoreWarnings();
 519         // parse_url() returns an array without scheme for some invalid URLs, e.g.
 520         // parse_url("%0Ahttp://example.com") == array( 'host' => '%0Ahttp', 'path' => 'example.com' )
 521         if ( !$bits || !isset( $bits['scheme'] ) ) {
 522                 return false;
 523         }
 524
 525         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
 526         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
 527                 $bits['delimiter'] = '://';
 528         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
 529                 $bits['delimiter'] = ':';
 530                 // parse_url detects for news: and mailto: the host part of an url as path
 531                 // We have to correct this wrong detection
 532                 if ( isset( $bits['path'] ) ) {
 533                         $bits['host'] = $bits['path'];
 534                         $bits['path'] = '';
 535                 }
 536         } else {
 537                 return false;
 538         }
 539
 540         /* Provide an empty host for eg. file:/// urls (see bug 28627) */
 541         if ( !isset( $bits['host'] ) ) {
 542                 $bits['host'] = '';
 543
 544                 /* parse_url loses the third / for file:///c:/ urls (but not on variants) */
 545                 if ( substr( $bits['path'], 0, 1 ) !== '/' ) {
 546                         $bits['path'] = '/' . $bits['path'];
 547                 }
 548         }
 549
 550         // If the URL was protocol-relative, fix scheme and delimiter
 551         if ( $wasRelative ) {
 552                 $bits['scheme'] = '';
 553                 $bits['delimiter'] = '//';
 554         }
 555         return $bits;
 556 }
 557
 558 /**
 559  * Make a URL index, appropriate for the el_index field of externallinks.
 560  *
 561  * @param $url String
 562  * @return String
 563  */
 564 function wfMakeUrlIndex( $url ) {
 565         $bits = wfParseUrl( $url );
 566
 567         // Reverse the labels in the hostname, convert to lower case
 568         // For emails reverse domainpart only
 569         if ( $bits['scheme'] == 'mailto' ) {
 570                 $mailparts = explode( '@', $bits['host'], 2 );
 571                 if ( count( $mailparts ) === 2 ) {
 572                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
 573                 } else {
 574                         // No domain specified, don't mangle it
 575                         $domainpart = '';
 576                 }
 577                 $reversedHost = $domainpart . '@' . $mailparts[0];
 578         } else {
 579                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
 580         }
 581         // Add an extra dot to the end
 582         // Why? Is it in wrong place in mailto links?
 583         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
 584                 $reversedHost .= '.';
 585         }
 586         // Reconstruct the pseudo-URL
 587         $prot = $bits['scheme'];
 588         $index = $prot . $bits['delimiter'] . $reversedHost;
 589         // Leave out user and password. Add the port, path, query and fragment
 590         if ( isset( $bits['port'] ) ) {
 591                 $index .= ':' . $bits['port'];
 592         }
 593         if ( isset( $bits['path'] ) ) {
 594                 $index .= $bits['path'];
 595         } else {
 596                 $index .= '/';
 597         }
 598         if ( isset( $bits['query'] ) ) {
 599                 $index .= '?' . $bits['query'];
 600         }
 601         if ( isset( $bits['fragment'] ) ) {
 602                 $index .= '#' . $bits['fragment'];
 603         }
 604         return $index;
 605 }
 606
 607 /**
 608  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
 609  * In normal operation this is a NOP.
 610  *
 611  * Controlling globals:
 612  * $wgDebugLogFile - points to the log file
 613  * $wgProfileOnly - if set, normal debug messages will not be recorded.
 614  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
 615  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
 616  *
 617  * @param $text String
 618  * @param $logonly Bool: set true to avoid appearing in HTML when $wgDebugComments is set
 619  */
 620 function wfDebug( $text, $logonly = false ) {
 621         global $wgOut, $wgDebugLogFile, $wgDebugComments, $wgProfileOnly, $wgDebugRawPage;
 622         global $wgDebugLogPrefix, $wgShowDebug;
 623
 624         static $cache = array(); // Cache of unoutputted messages
 625         $text = wfDebugTimer() . $text;
 626
 627         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
 628                 return;
 629         }
 630
 631         if ( ( $wgDebugComments || $wgShowDebug ) && !$logonly ) {
 632                 $cache[] = $text;
 633
 634                 if ( isset( $wgOut ) && is_object( $wgOut ) ) {
 635                         // add the message and any cached messages to the output
 636                         array_map( array( $wgOut, 'debug' ), $cache );
 637                         $cache = array();
 638                 }
 639         }
 640         if ( wfRunHooks( 'Debug', array( $text, null /* no log group */ ) ) ) {
 641                 if ( $wgDebugLogFile != '' && !$wgProfileOnly ) {
 642                         # Strip unprintables; they can switch terminal modes when binary data
 643                         # gets dumped, which is pretty annoying.
 644                         $text = preg_replace( '![\x00-\x08\x0b\x0c\x0e-\x1f]!', ' ', $text );
 645                         $text = $wgDebugLogPrefix . $text;
 646                         wfErrorLog( $text, $wgDebugLogFile );
 647                 }
 648         }
 649 }
 650
 651 /**
 652  * Returns true if debug logging should be suppressed if $wgDebugRawPage = false
 653  */
 654 function wfIsDebugRawPage() {
 655         static $cache;
 656         if ( $cache !== null ) {
 657                 return $cache;
 658         }
 659         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
 660         if ( ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' )
 661                 || (
 662                         isset( $_SERVER['SCRIPT_NAME'] )
 663                         && substr( $_SERVER['SCRIPT_NAME'], -8 ) == 'load.php'
 664                 ) )
 665         {
 666                 $cache = true;
 667         } else {
 668                 $cache = false;
 669         }
 670         return $cache;
 671 }
 672
 673 /**
 674  * Get microsecond timestamps for debug logs
 675  *
 676  * @return string
 677  */
 678 function wfDebugTimer() {
 679         global $wgDebugTimestamps;
 680         if ( !$wgDebugTimestamps ) {
 681                 return '';
 682         }
 683         static $start = null;
 684
 685         if ( $start === null ) {
 686                 $start = microtime( true );
 687                 $prefix = "\n$start";
 688         } else {
 689                 $prefix = sprintf( "%6.4f", microtime( true ) - $start );
 690         }
 691
 692         return $prefix . '  ';
 693 }
 694
 695 /**
 696  * Send a line giving PHP memory usage.
 697  *
 698  * @param $exact Bool: print exact values instead of kilobytes (default: false)
 699  */
 700 function wfDebugMem( $exact = false ) {
 701         $mem = memory_get_usage();
 702         if( !$exact ) {
 703                 $mem = floor( $mem / 1024 ) . ' kilobytes';
 704         } else {
 705                 $mem .= ' bytes';
 706         }
 707         wfDebug( "Memory usage: $mem\n" );
 708 }
 709
 710 /**
 711  * Send a line to a supplementary debug log file, if configured, or main debug log if not.
 712  * $wgDebugLogGroups[$logGroup] should be set to a filename to send to a separate log.
 713  *
 714  * @param $logGroup String
 715  * @param $text String
 716  * @param $public Bool: whether to log the event in the public log if no private
 717  *                     log file is specified, (default true)
 718  */
 719 function wfDebugLog( $logGroup, $text, $public = true ) {
 720         global $wgDebugLogGroups, $wgShowHostnames;
 721         $text = trim( $text ) . "\n";
 722         if( isset( $wgDebugLogGroups[$logGroup] ) ) {
 723                 $time = wfTimestamp( TS_DB );
 724                 $wiki = wfWikiID();
 725                 if ( $wgShowHostnames ) {
 726                         $host = wfHostname();
 727                 } else {
 728                         $host = '';
 729                 }
 730                 if ( wfRunHooks( 'Debug', array( $text, $logGroup ) ) ) {
 731                         wfErrorLog( "$time $host $wiki: $text", $wgDebugLogGroups[$logGroup] );
 732                 }
 733         } elseif ( $public === true ) {
 734                 wfDebug( $text, true );
 735         }
 736 }
 737
 738 /**
 739  * Log for database errors
 740  *
 741  * @param $text String: database error message.
 742  */
 743 function wfLogDBError( $text ) {
 744         global $wgDBerrorLog, $wgDBname;
 745         if ( $wgDBerrorLog ) {
 746                 $host = trim(`hostname`);
 747                 $text = date( 'D M j G:i:s T Y' ) . "\t$host\t$wgDBname\t$text";
 748                 wfErrorLog( $text, $wgDBerrorLog );
 749         }
 750 }
 751
 752 /**
 753  * Log to a file without getting "file size exceeded" signals.
 754  *
 755  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
 756  * send lines to the specified port, prefixed by the specified prefix and a space.
 757  *
 758  * @param $text String
 759  * @param $file String filename
 760  */
 761 function wfErrorLog( $text, $file ) {
 762         if ( substr( $file, 0, 4 ) == 'udp:' ) {
 763                 # Needs the sockets extension
 764                 if ( preg_match( '!^(tcp|udp):(?://)?\[([0-9a-fA-F:]+)\]:(\d+)(?:/(.*))?$!', $file, $m ) ) {
 765                         // IPv6 bracketed host
 766                         $host = $m[2];
 767                         $port = intval( $m[3] );
 768                         $prefix = isset( $m[4] ) ? $m[4] : false;
 769                         $domain = AF_INET6;
 770                 } elseif ( preg_match( '!^(tcp|udp):(?://)?([a-zA-Z0-9.-]+):(\d+)(?:/(.*))?$!', $file, $m ) ) {
 771                         $host = $m[2];
 772                         if ( !IP::isIPv4( $host ) ) {
 773                                 $host = gethostbyname( $host );
 774                         }
 775                         $port = intval( $m[3] );
 776                         $prefix = isset( $m[4] ) ? $m[4] : false;
 777                         $domain = AF_INET;
 778                 } else {
 779                         throw new MWException( __METHOD__ . ': Invalid UDP specification' );
 780                 }
 781
 782                 // Clean it up for the multiplexer
 783                 if ( strval( $prefix ) !== '' ) {
 784                         $text = preg_replace( '/^/m', $prefix . ' ', $text );
 785
 786                         // Limit to 64KB
 787                         if ( strlen( $text ) > 65534 ) {
 788                                 $text = substr( $text, 0, 65534 );
 789                         }
 790
 791                         if ( substr( $text, -1 ) != "\n" ) {
 792                                 $text .= "\n";
 793                         }
 794                 } elseif ( strlen( $text ) > 65535 ) {
 795                         $text = substr( $text, 0, 65535 );
 796                 }
 797
 798                 $sock = socket_create( $domain, SOCK_DGRAM, SOL_UDP );
 799                 if ( !$sock ) {
 800                         return;
 801                 }
 802                 socket_sendto( $sock, $text, strlen( $text ), 0, $host, $port );
 803                 socket_close( $sock );
 804         } else {
 805                 wfSuppressWarnings();
 806                 $exists = file_exists( $file );
 807                 $size = $exists ? filesize( $file ) : false;
 808                 if ( !$exists || ( $size !== false && $size + strlen( $text ) < 0x7fffffff ) ) {
 809                         file_put_contents( $file, $text, FILE_APPEND );
 810                 }
 811                 wfRestoreWarnings();
 812         }
 813 }
 814
 815 /**
 816  * @todo document
 817  */
 818 function wfLogProfilingData() {
 819         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
 820         global $wgProfileLimit, $wgUser;
 821
 822         $profiler = Profiler::instance();
 823
 824         # Profiling must actually be enabled...
 825         if ( $profiler->isStub() ) {
 826                 return;
 827         }
 828
 829         // Get total page request time and only show pages that longer than
 830         // $wgProfileLimit time (default is 0)
 831         $now = wfTime();
 832         $elapsed = $now - $wgRequestTime;
 833         if ( $elapsed <= $wgProfileLimit ) {
 834                 return;
 835         }
 836
 837         $profiler->logData();
 838
 839         // Check whether this should be logged in the debug file.
 840         if ( $wgDebugLogFile == '' || ( !$wgDebugRawPage && wfIsDebugRawPage() ) ) {
 841                 return;
 842         }
 843
 844         $forward = '';
 845         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
 846                 $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
 847         }
 848         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
 849                 $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
 850         }
 851         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
 852                 $forward .= ' from ' . $_SERVER['HTTP_FROM'];
 853         }
 854         if ( $forward ) {
 855                 $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
 856         }
 857         // Don't load $wgUser at this late stage just for statistics purposes
 858         // @todo FIXME: We can detect some anons even if it is not loaded. See User::getId()
 859         if ( $wgUser->isItemLoaded( 'id' ) && $wgUser->isAnon() ) {
 860                 $forward .= ' anon';
 861         }
 862         $log = sprintf( "%s\t%04.3f\t%s\n",
 863                 gmdate( 'YmdHis' ), $elapsed,
 864                 urldecode( $wgRequest->getRequestURL() . $forward ) );
 865
 866         wfErrorLog( $log . $profiler->getOutput(), $wgDebugLogFile );
 867 }
 868
 869 /**
 870  * Check if the wiki read-only lock file is present. This can be used to lock
 871  * off editing functions, but doesn't guarantee that the database will not be
 872  * modified.
 873  *
 874  * @return bool
 875  */
 876 function wfReadOnly() {
 877         global $wgReadOnlyFile, $wgReadOnly;
 878
 879         if ( !is_null( $wgReadOnly ) ) {
 880                 return (bool)$wgReadOnly;
 881         }
 882         if ( $wgReadOnlyFile == '' ) {
 883                 return false;
 884         }
 885         // Set $wgReadOnly for faster access next time
 886         if ( is_file( $wgReadOnlyFile ) ) {
 887                 $wgReadOnly = file_get_contents( $wgReadOnlyFile );
 888         } else {
 889                 $wgReadOnly = false;
 890         }
 891         return (bool)$wgReadOnly;
 892 }
 893
 894 function wfReadOnlyReason() {
 895         global $wgReadOnly;
 896         wfReadOnly();
 897         return $wgReadOnly;
 898 }
 899
 900 /**
 901  * Return a Language object from $langcode
 902  *
 903  * @param $langcode Mixed: either:
 904  *                  - a Language object
 905  *                  - code of the language to get the message for, if it is
 906  *                    a valid code create a language for that language, if
 907  *                    it is a string but not a valid code then make a basic
 908  *                    language object
 909  *                  - a boolean: if it's false then use the current users
 910  *                    language (as a fallback for the old parameter
 911  *                    functionality), or if it is true then use the wikis
 912  * @return Language object
 913  */
 914 function wfGetLangObj( $langcode = false ) {
 915         # Identify which language to get or create a language object for.
 916         # Using is_object here due to Stub objects.
 917         if( is_object( $langcode ) ) {
 918                 # Great, we already have the object (hopefully)!
 919                 return $langcode;
 920         }
 921
 922         global $wgContLang, $wgLanguageCode;
 923         if( $langcode === true || $langcode === $wgLanguageCode ) {
 924                 # $langcode is the language code of the wikis content language object.
 925                 # or it is a boolean and value is true
 926                 return $wgContLang;
 927         }
 928
 929         global $wgLang;
 930         if( $langcode === false || $langcode === $wgLang->getCode() ) {
 931                 # $langcode is the language code of user language object.
 932                 # or it was a boolean and value is false
 933                 return $wgLang;
 934         }
 935
 936         $validCodes = array_keys( Language::getLanguageNames() );
 937         if( in_array( $langcode, $validCodes ) ) {
 938                 # $langcode corresponds to a valid language.
 939                 return Language::factory( $langcode );
 940         }
 941
 942         # $langcode is a string, but not a valid language code; use content language.
 943         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
 944         return $wgContLang;
 945 }
 946
 947 /**
 948  * Old function when $wgBetterDirectionality existed
 949  * Removed in core, kept in extensions for backwards compat.
 950  *
 951  * @deprecated since 1.18
 952  * @return Language
 953  */
 954 function wfUILang() {
 955         global $wgLang;
 956         return $wgLang;
 957 }
 958
 959 /**
 960  * This is the new function for getting translated interface messages.
 961  * See the Message class for documentation how to use them.
 962  * The intention is that this function replaces all old wfMsg* functions.
 963  * @param $key \string Message key.
 964  * Varargs: normal message parameters.
 965  * @return Message
 966  * @since 1.17
 967  */
 968 function wfMessage( $key /*...*/) {
 969         $params = func_get_args();
 970         array_shift( $params );
 971         if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 972                 $params = $params[0];
 973         }
 974         return new Message( $key, $params );
 975 }
 976
 977 /**
 978  * This function accepts multiple message keys and returns a message instance
 979  * for the first message which is non-empty. If all messages are empty then an
 980  * instance of the first message key is returned.
 981  * @param varargs: message keys
 982  * @return Message
 983  * @since 1.18
 984  */
 985 function wfMessageFallback( /*...*/ ) {
 986         $args = func_get_args();
 987         return MWFunction::callArray( 'Message::newFallbackSequence', $args );
 988 }
 989
 990 /**
 991  * Get a message from anywhere, for the current user language.
 992  *
 993  * Use wfMsgForContent() instead if the message should NOT
 994  * change depending on the user preferences.
 995  *
 996  * @param $key String: lookup key for the message, usually
 997  *    defined in languages/Language.php
 998  *
 999  * Parameters to the message, which can be used to insert variable text into
1000  * it, can be passed to this function in the following formats:
1001  * - One per argument, starting at the second parameter
1002  * - As an array in the second parameter
1003  * These are not shown in the function definition.
1004  *
1005  * @return String
1006  */
1007 function wfMsg( $key ) {
1008         $args = func_get_args();
1009         array_shift( $args );
1010         return wfMsgReal( $key, $args );
1011 }
1012
1013 /**
1014  * Same as above except doesn't transform the message
1015  *
1016  * @param $key String
1017  * @return String
1018  */
1019 function wfMsgNoTrans( $key ) {
1020         $args = func_get_args();
1021         array_shift( $args );
1022         return wfMsgReal( $key, $args, true, false, false );
1023 }
1024
1025 /**
1026  * Get a message from anywhere, for the current global language
1027  * set with $wgLanguageCode.
1028  *
1029  * Use this if the message should NOT change dependent on the
1030  * language set in the user's preferences. This is the case for
1031  * most text written into logs, as well as link targets (such as
1032  * the name of the copyright policy page). Link titles, on the
1033  * other hand, should be shown in the UI language.
1034  *
1035  * Note that MediaWiki allows users to change the user interface
1036  * language in their preferences, but a single installation
1037  * typically only contains content in one language.
1038  *
1039  * Be wary of this distinction: If you use wfMsg() where you should
1040  * use wfMsgForContent(), a user of the software may have to
1041  * customize potentially hundreds of messages in
1042  * order to, e.g., fix a link in every possible language.
1043  *
1044  * @param $key String: lookup key for the message, usually
1045  *     defined in languages/Language.php
1046  * @return String
1047  */
1048 function wfMsgForContent( $key ) {
1049         global $wgForceUIMsgAsContentMsg;
1050         $args = func_get_args();
1051         array_shift( $args );
1052         $forcontent = true;
1053         if( is_array( $wgForceUIMsgAsContentMsg ) &&
1054                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
1055         {
1056                 $forcontent = false;
1057         }
1058         return wfMsgReal( $key, $args, true, $forcontent );
1059 }
1060
1061 /**
1062  * Same as above except doesn't transform the message
1063  *
1064  * @param $key String
1065  * @return String
1066  */
1067 function wfMsgForContentNoTrans( $key ) {
1068         global $wgForceUIMsgAsContentMsg;
1069         $args = func_get_args();
1070         array_shift( $args );
1071         $forcontent = true;
1072         if( is_array( $wgForceUIMsgAsContentMsg ) &&
1073                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
1074         {
1075                 $forcontent = false;
1076         }
1077         return wfMsgReal( $key, $args, true, $forcontent, false );
1078 }
1079
1080 /**
1081  * Really get a message
1082  *
1083  * @param $key String: key to get.
1084  * @param $args
1085  * @param $useDB Boolean
1086  * @param $forContent Mixed: Language code, or false for user lang, true for content lang.
1087  * @param $transform Boolean: Whether or not to transform the message.
1088  * @return String: the requested message.
1089  */
1090 function wfMsgReal( $key, $args, $useDB = true, $forContent = false, $transform = true ) {
1091         wfProfileIn( __METHOD__ );
1092         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
1093         $message = wfMsgReplaceArgs( $message, $args );
1094         wfProfileOut( __METHOD__ );
1095         return $message;
1096 }
1097
1098 /**
1099  * Fetch a message string value, but don't replace any keys yet.
1100  *
1101  * @param $key String
1102  * @param $useDB Bool
1103  * @param $langCode String: Code of the language to get the message for, or
1104  *                  behaves as a content language switch if it is a boolean.
1105  * @param $transform Boolean: whether to parse magic words, etc.
1106  * @return string
1107  */
1108 function wfMsgGetKey( $key, $useDB = true, $langCode = false, $transform = true ) {
1109         wfRunHooks( 'NormalizeMessageKey', array( &$key, &$useDB, &$langCode, &$transform ) );
1110
1111         $cache = MessageCache::singleton();
1112         $message = $cache->get( $key, $useDB, $langCode );
1113         if( $message === false ) {
1114                 $message = '&lt;' . htmlspecialchars( $key ) . '&gt;';
1115         } elseif ( $transform ) {
1116                 $message = $cache->transform( $message );
1117         }
1118         return $message;
1119 }
1120
1121 /**
1122  * Replace message parameter keys on the given formatted output.
1123  *
1124  * @param $message String
1125  * @param $args Array
1126  * @return string
1127  * @private
1128  */
1129 function wfMsgReplaceArgs( $message, $args ) {
1130         # Fix windows line-endings
1131         # Some messages are split with explode("\n", $msg)
1132         $message = str_replace( "\r", '', $message );
1133
1134         // Replace arguments
1135         if ( count( $args ) ) {
1136                 if ( is_array( $args[0] ) ) {
1137                         $args = array_values( $args[0] );
1138                 }
1139                 $replacementKeys = array();
1140                 foreach( $args as $n => $param ) {
1141                         $replacementKeys['$' . ( $n + 1 )] = $param;
1142                 }
1143                 $message = strtr( $message, $replacementKeys );
1144         }
1145
1146         return $message;
1147 }
1148
1149 /**
1150  * Return an HTML-escaped version of a message.
1151  * Parameter replacements, if any, are done *after* the HTML-escaping,
1152  * so parameters may contain HTML (eg links or form controls). Be sure
1153  * to pre-escape them if you really do want plaintext, or just wrap
1154  * the whole thing in htmlspecialchars().
1155  *
1156  * @param $key String
1157  * @param string ... parameters
1158  * @return string
1159  */
1160 function wfMsgHtml( $key ) {
1161         $args = func_get_args();
1162         array_shift( $args );
1163         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key ) ), $args );
1164 }
1165
1166 /**
1167  * Return an HTML version of message
1168  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
1169  * so parameters may contain HTML (eg links or form controls). Be sure
1170  * to pre-escape them if you really do want plaintext, or just wrap
1171  * the whole thing in htmlspecialchars().
1172  *
1173  * @param $key String
1174  * @param string ... parameters
1175  * @return string
1176  */
1177 function wfMsgWikiHtml( $key ) {
1178         $args = func_get_args();
1179         array_shift( $args );
1180         return wfMsgReplaceArgs(
1181                 MessageCache::singleton()->parse( wfMsgGetKey( $key ), null, /* can't be set to false */ true )->getText(),
1182                 $args );
1183 }
1184
1185 /**
1186  * Returns message in the requested format
1187  * @param $key String: key of the message
1188  * @param $options Array: processing rules. Can take the following options:
1189  *   <i>parse</i>: parses wikitext to HTML
1190  *   <i>parseinline</i>: parses wikitext to HTML and removes the surrounding
1191  *       p's added by parser or tidy
1192  *   <i>escape</i>: filters message through htmlspecialchars
1193  *   <i>escapenoentities</i>: same, but allows entity references like &#160; through
1194  *   <i>replaceafter</i>: parameters are substituted after parsing or escaping
1195  *   <i>parsemag</i>: transform the message using magic phrases
1196  *   <i>content</i>: fetch message for content language instead of interface
1197  * Also can accept a single associative argument, of the form 'language' => 'xx':
1198  *   <i>language</i>: Language object or language code to fetch message for
1199  *       (overriden by <i>content</i>).
1200  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
1201  *
1202  * @return String
1203  */
1204 function wfMsgExt( $key, $options ) {
1205         $args = func_get_args();
1206         array_shift( $args );
1207         array_shift( $args );
1208         $options = (array)$options;
1209
1210         foreach( $options as $arrayKey => $option ) {
1211                 if( !preg_match( '/^[0-9]+|language$/', $arrayKey ) ) {
1212                         # An unknown index, neither numeric nor "language"
1213                         wfWarn( "wfMsgExt called with incorrect parameter key $arrayKey", 1, E_USER_WARNING );
1214                 } elseif( preg_match( '/^[0-9]+$/', $arrayKey ) && !in_array( $option,
1215                 array( 'parse', 'parseinline', 'escape', 'escapenoentities',
1216                 'replaceafter', 'parsemag', 'content' ) ) ) {
1217                         # A numeric index with unknown value
1218                         wfWarn( "wfMsgExt called with incorrect parameter $option", 1, E_USER_WARNING );
1219                 }
1220         }
1221
1222         if( in_array( 'content', $options, true ) ) {
1223                 $forContent = true;
1224                 $langCode = true;
1225                 $langCodeObj = null;
1226         } elseif( array_key_exists( 'language', $options ) ) {
1227                 $forContent = false;
1228                 $langCode = wfGetLangObj( $options['language'] );
1229                 $langCodeObj = $langCode;
1230         } else {
1231                 $forContent = false;
1232                 $langCode = false;
1233                 $langCodeObj = null;
1234         }
1235
1236         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
1237
1238         if( !in_array( 'replaceafter', $options, true ) ) {
1239                 $string = wfMsgReplaceArgs( $string, $args );
1240         }
1241
1242         $messageCache = MessageCache::singleton();
1243         if( in_array( 'parse', $options, true ) ) {
1244                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj )->getText();
1245         } elseif ( in_array( 'parseinline', $options, true ) ) {
1246                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj )->getText();
1247                 $m = array();
1248                 if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
1249                         $string = $m[1];
1250                 }
1251         } elseif ( in_array( 'parsemag', $options, true ) ) {
1252                 $string = $messageCache->transform( $string,
1253                                 !$forContent, $langCodeObj );
1254         }
1255
1256         if ( in_array( 'escape', $options, true ) ) {
1257                 $string = htmlspecialchars ( $string );
1258         } elseif ( in_array( 'escapenoentities', $options, true ) ) {
1259                 $string = Sanitizer::escapeHtmlAllowEntities( $string );
1260         }
1261
1262         if( in_array( 'replaceafter', $options, true ) ) {
1263                 $string = wfMsgReplaceArgs( $string, $args );
1264         }
1265
1266         return $string;
1267 }
1268
1269 /**
1270  * Since wfMsg() and co suck, they don't return false if the message key they
1271  * looked up didn't exist but a XHTML string, this function checks for the
1272  * nonexistance of messages by checking the MessageCache::get() result directly.
1273  *
1274  * @param $key      String: the message key looked up
1275  * @return Boolean True if the message *doesn't* exist.
1276  */
1277 function wfEmptyMsg( $key ) {
1278         return MessageCache::singleton()->get( $key, /*useDB*/true, /*content*/false ) === false;
1279 }
1280
1281 /**
1282  * Throw a debugging exception. This function previously once exited the process,
1283  * but now throws an exception instead, with similar results.
1284  *
1285  * @param $msg String: message shown when dieing.
1286  */
1287 function wfDebugDieBacktrace( $msg = '' ) {
1288         throw new MWException( $msg );
1289 }
1290
1291 /**
1292  * Fetch server name for use in error reporting etc.
1293  * Use real server name if available, so we know which machine
1294  * in a server farm generated the current page.
1295  *
1296  * @return string
1297  */
1298 function wfHostname() {
1299         static $host;
1300         if ( is_null( $host ) ) {
1301                 if ( function_exists( 'posix_uname' ) ) {
1302                         // This function not present on Windows
1303                         $uname = posix_uname();
1304                 } else {
1305                         $uname = false;
1306                 }
1307                 if( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1308                         $host = $uname['nodename'];
1309                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1310                         # Windows computer name
1311                         $host = getenv( 'COMPUTERNAME' );
1312                 } else {
1313                         # This may be a virtual server.
1314                         $host = $_SERVER['SERVER_NAME'];
1315                 }
1316         }
1317         return $host;
1318 }
1319
1320 /**
1321  * Returns a HTML comment with the elapsed time since request.
1322  * This method has no side effects.
1323  *
1324  * @return string
1325  */
1326 function wfReportTime() {
1327         global $wgRequestTime, $wgShowHostnames;
1328
1329         $now = wfTime();
1330         $elapsed = $now - $wgRequestTime;
1331
1332         return $wgShowHostnames
1333                 ? sprintf( '<!-- Served by %s in %01.3f secs. -->', wfHostname(), $elapsed )
1334                 : sprintf( '<!-- Served in %01.3f secs. -->', $elapsed );
1335 }
1336
1337 /**
1338  * Safety wrapper for debug_backtrace().
1339  *
1340  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
1341  * murky circumstances, which may be triggered in part by stub objects
1342  * or other fancy talkin'.
1343  *
1344  * Will return an empty array if Zend Optimizer is detected or if
1345  * debug_backtrace is disabled, otherwise the output from
1346  * debug_backtrace() (trimmed).
1347  *
1348  * @return array of backtrace information
1349  */
1350 function wfDebugBacktrace( $limit = 0 ) {
1351         static $disabled = null;
1352
1353         if( extension_loaded( 'Zend Optimizer' ) ) {
1354                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
1355                 return array();
1356         }
1357
1358         if ( is_null( $disabled ) ) {
1359                 $disabled = false;
1360                 $functions = explode( ',', ini_get( 'disable_functions' ) );
1361                 $functions = array_map( 'trim', $functions );
1362                 $functions = array_map( 'strtolower', $functions );
1363                 if ( in_array( 'debug_backtrace', $functions ) ) {
1364                         wfDebug( "debug_backtrace is in disabled_functions\n" );
1365                         $disabled = true;
1366                 }
1367         }
1368         if ( $disabled ) {
1369                 return array();
1370         }
1371
1372         if ( $limit && version_compare( PHP_VERSION, '5.4.0', '>=' ) ) {
1373                 return array_slice( debug_backtrace( DEBUG_BACKTRACE_PROVIDE_OBJECT, 1 ), 1 );
1374         } else {
1375                 return array_slice( debug_backtrace(), 1 );
1376         }
1377 }
1378
1379 /**
1380  * Get a debug backtrace as a string
1381  *
1382  * @return string
1383  */
1384 function wfBacktrace() {
1385         global $wgCommandLineMode;
1386
1387         if ( $wgCommandLineMode ) {
1388                 $msg = '';
1389         } else {
1390                 $msg = "<ul>\n";
1391         }
1392         $backtrace = wfDebugBacktrace();
1393         foreach( $backtrace as $call ) {
1394                 if( isset( $call['file'] ) ) {
1395                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
1396                         $file = $f[count( $f ) - 1];
1397                 } else {
1398                         $file = '-';
1399                 }
1400                 if( isset( $call['line'] ) ) {
1401                         $line = $call['line'];
1402                 } else {
1403                         $line = '-';
1404                 }
1405                 if ( $wgCommandLineMode ) {
1406                         $msg .= "$file line $line calls ";
1407                 } else {
1408                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
1409                 }
1410                 if( !empty( $call['class'] ) ) {
1411                         $msg .= $call['class'] . $call['type'];
1412                 }
1413                 $msg .= $call['function'] . '()';
1414
1415                 if ( $wgCommandLineMode ) {
1416                         $msg .= "\n";
1417                 } else {
1418                         $msg .= "</li>\n";
1419                 }
1420         }
1421         if ( $wgCommandLineMode ) {
1422                 $msg .= "\n";
1423         } else {
1424                 $msg .= "</ul>\n";
1425         }
1426
1427         return $msg;
1428 }
1429
1430 /**
1431  * Get the name of the function which called this function
1432  *
1433  * @param $level Int
1434  * @return Bool|string
1435  */
1436 function wfGetCaller( $level = 2 ) {
1437         $backtrace = wfDebugBacktrace( $level );
1438         if ( isset( $backtrace[$level] ) ) {
1439                 return wfFormatStackFrame( $backtrace[$level] );
1440         } else {
1441                 $caller = 'unknown';
1442         }
1443         return $caller;
1444 }
1445
1446 /**
1447  * Return a string consisting of callers in the stack. Useful sometimes
1448  * for profiling specific points.
1449  *
1450  * @param $limit The maximum depth of the stack frame to return, or false for
1451  *               the entire stack.
1452  * @return String
1453  */
1454 function wfGetAllCallers( $limit = 3 ) {
1455         $trace = array_reverse( wfDebugBacktrace() );
1456         if ( !$limit || $limit > count( $trace ) - 1 ) {
1457                 $limit = count( $trace ) - 1;
1458         }
1459         $trace = array_slice( $trace, -$limit - 1, $limit );
1460         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1461 }
1462
1463 /**
1464  * Return a string representation of frame
1465  *
1466  * @param $frame Array
1467  * @return Bool
1468  */
1469 function wfFormatStackFrame( $frame ) {
1470         return isset( $frame['class'] ) ?
1471                 $frame['class'] . '::' . $frame['function'] :
1472                 $frame['function'];
1473 }
1474
1475
1476 /* Some generic result counters, pulled out of SearchEngine */
1477
1478
1479 /**
1480  * @todo document
1481  *
1482  * @param $offset Int
1483  * @param $limit Int
1484  * @return String
1485  */
1486 function wfShowingResults( $offset, $limit ) {
1487         global $wgLang;
1488         return wfMsgExt(
1489                 'showingresults',
1490                 array( 'parseinline' ),
1491                 $wgLang->formatNum( $limit ),
1492                 $wgLang->formatNum( $offset + 1 )
1493         );
1494 }
1495
1496 /**
1497  * Generate (prev x| next x) (20|50|100...) type links for paging
1498  *
1499  * @param $offset String
1500  * @param $limit Integer
1501  * @param $link String
1502  * @param $query String: optional URL query parameter string
1503  * @param $atend Bool: optional param for specified if this is the last page
1504  * @return String
1505  */
1506 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
1507         global $wgLang;
1508         $fmtLimit = $wgLang->formatNum( $limit );
1509         // @todo FIXME: Why on earth this needs one message for the text and another one for tooltip?
1510         # Get prev/next link display text
1511         $prev = wfMsgExt( 'prevn', array( 'parsemag', 'escape' ), $fmtLimit );
1512         $next = wfMsgExt( 'nextn', array( 'parsemag', 'escape' ), $fmtLimit );
1513         # Get prev/next link title text
1514         $pTitle = wfMsgExt( 'prevn-title', array( 'parsemag', 'escape' ), $fmtLimit );
1515         $nTitle = wfMsgExt( 'nextn-title', array( 'parsemag', 'escape' ), $fmtLimit );
1516         # Fetch the title object
1517         if( is_object( $link ) ) {
1518                 $title =& $link;
1519         } else {
1520                 $title = Title::newFromText( $link );
1521                 if( is_null( $title ) ) {
1522                         return false;
1523                 }
1524         }
1525         # Make 'previous' link
1526         if( 0 != $offset ) {
1527                 $po = $offset - $limit;
1528                 $po = max( $po, 0 );
1529                 $q = "limit={$limit}&offset={$po}";
1530                 if( $query != '' ) {
1531                         $q .= '&' . $query;
1532                 }
1533                 $plink = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$pTitle}\" class=\"mw-prevlink\">{$prev}</a>";
1534         } else {
1535                 $plink = $prev;
1536         }
1537         # Make 'next' link
1538         $no = $offset + $limit;
1539         $q = "limit={$limit}&offset={$no}";
1540         if( $query != '' ) {
1541                 $q .= '&' . $query;
1542         }
1543         if( $atend ) {
1544                 $nlink = $next;
1545         } else {
1546                 $nlink = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$nTitle}\" class=\"mw-nextlink\">{$next}</a>";
1547         }
1548         # Make links to set number of items per page
1549         $nums = $wgLang->pipeList( array(
1550                 wfNumLink( $offset, 20, $title, $query ),
1551                 wfNumLink( $offset, 50, $title, $query ),
1552                 wfNumLink( $offset, 100, $title, $query ),
1553                 wfNumLink( $offset, 250, $title, $query ),
1554                 wfNumLink( $offset, 500, $title, $query )
1555         ) );
1556         return wfMsgHtml( 'viewprevnext', $plink, $nlink, $nums );
1557 }
1558
1559 /**
1560  * Generate links for (20|50|100...) items-per-page links
1561  *
1562  * @param $offset String
1563  * @param $limit Integer
1564  * @param $title Title
1565  * @param $query String: optional URL query parameter string
1566  */
1567 function wfNumLink( $offset, $limit, $title, $query = '' ) {
1568         global $wgLang;
1569         if( $query == '' ) {
1570                 $q = '';
1571         } else {
1572                 $q = $query.'&';
1573         }
1574         $q .= "limit={$limit}&offset={$offset}";
1575         $fmtLimit = $wgLang->formatNum( $limit );
1576         $lTitle = wfMsgExt( 'shown-title', array( 'parsemag', 'escape' ), $limit );
1577         $s = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$lTitle}\" class=\"mw-numlink\">{$fmtLimit}</a>";
1578         return $s;
1579 }
1580
1581 /**
1582  * @todo document
1583  * @todo FIXME: We may want to blacklist some broken browsers
1584  *
1585  * @param $force Bool
1586  * @return bool Whereas client accept gzip compression
1587  */
1588 function wfClientAcceptsGzip( $force = false ) {
1589         static $result = null;
1590         if ( $result === null || $force ) {
1591                 $result = false;
1592                 if( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1593                         # @todo FIXME: We may want to blacklist some broken browsers
1594                         $m = array();
1595                         if( preg_match(
1596                                 '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1597                                 $_SERVER['HTTP_ACCEPT_ENCODING'],
1598                                 $m )
1599                         )
1600                         {
1601                                 if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1602                                         $result = false;
1603                                         return $result;
1604                                 }
1605                                 wfDebug( " accepts gzip\n" );
1606                                 $result = true;
1607                         }
1608                 }
1609         }
1610         return $result;
1611 }
1612
1613 /**
1614  * Obtain the offset and limit values from the request string;
1615  * used in special pages
1616  *
1617  * @param $deflimit Int default limit if none supplied
1618  * @param $optionname String Name of a user preference to check against
1619  * @return array
1620  *
1621  */
1622 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
1623         global $wgRequest;
1624         return $wgRequest->getLimitOffset( $deflimit, $optionname );
1625 }
1626
1627 /**
1628  * Escapes the given text so that it may be output using addWikiText()
1629  * without any linking, formatting, etc. making its way through. This
1630  * is achieved by substituting certain characters with HTML entities.
1631  * As required by the callers, <nowiki> is not used.
1632  *
1633  * @param $text String: text to be escaped
1634  * @return String
1635  */
1636 function wfEscapeWikiText( $text ) {
1637         $text = strtr( "\n$text", array(
1638                 '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
1639                 '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
1640                 '{' => '&#123;', '|' => '&#124;', '}' => '&#125;',
1641                 "\n#" => "\n&#35;", "\n*" => "\n&#42;",
1642                 "\n:" => "\n&#58;", "\n;" => "\n&#59;",
1643                 '://' => '&#58;//', 'ISBN ' => 'ISBN&#32;', 'RFC ' => 'RFC&#32;',
1644         ) );
1645         return substr( $text, 1 );
1646 }
1647
1648 /**
1649  * Get the current unix timetstamp with microseconds.  Useful for profiling
1650  * @return Float
1651  */
1652 function wfTime() {
1653         return microtime( true );
1654 }
1655
1656 /**
1657  * Sets dest to source and returns the original value of dest
1658  * If source is NULL, it just returns the value, it doesn't set the variable
1659  * If force is true, it will set the value even if source is NULL
1660  *
1661  * @param $dest Mixed
1662  * @param $source Mixed
1663  * @param $force Bool
1664  * @return Mixed
1665  */
1666 function wfSetVar( &$dest, $source, $force = false ) {
1667         $temp = $dest;
1668         if ( !is_null( $source ) || $force ) {
1669                 $dest = $source;
1670         }
1671         return $temp;
1672 }
1673
1674 /**
1675  * As for wfSetVar except setting a bit
1676  *
1677  * @param $dest Int
1678  * @param $bit Int
1679  * @param $state Bool
1680  */
1681 function wfSetBit( &$dest, $bit, $state = true ) {
1682         $temp = (bool)( $dest & $bit );
1683         if ( !is_null( $state ) ) {
1684                 if ( $state ) {
1685                         $dest |= $bit;
1686                 } else {
1687                         $dest &= ~$bit;
1688                 }
1689         }
1690         return $temp;
1691 }
1692
1693 /**
1694  * Windows-compatible version of escapeshellarg()
1695  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
1696  * function puts single quotes in regardless of OS.
1697  *
1698  * Also fixes the locale problems on Linux in PHP 5.2.6+ (bug backported to
1699  * earlier distro releases of PHP)
1700  *
1701  * @param varargs
1702  * @return String
1703  */
1704 function wfEscapeShellArg( ) {
1705         wfInitShellLocale();
1706
1707         $args = func_get_args();
1708         $first = true;
1709         $retVal = '';
1710         foreach ( $args as $arg ) {
1711                 if ( !$first ) {
1712                         $retVal .= ' ';
1713                 } else {
1714                         $first = false;
1715                 }
1716
1717                 if ( wfIsWindows() ) {
1718                         // Escaping for an MSVC-style command line parser and CMD.EXE
1719                         // Refs:
1720                         //  * http://web.archive.org/web/20020708081031/http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
1721                         //  * http://technet.microsoft.com/en-us/library/cc723564.aspx
1722                         //  * Bug #13518
1723                         //  * CR r63214
1724                         // Double the backslashes before any double quotes. Escape the double quotes.
1725                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
1726                         $arg = '';
1727                         $iteration = 0;
1728                         foreach ( $tokens as $token ) {
1729                                 if ( $iteration % 2 == 1 ) {
1730                                         // Delimiter, a double quote preceded by zero or more slashes
1731                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
1732                                 } elseif ( $iteration % 4 == 2 ) {
1733                                         // ^ in $token will be outside quotes, need to be escaped
1734                                         $arg .= str_replace( '^', '^^', $token );
1735                                 } else { // $iteration % 4 == 0
1736                                         // ^ in $token will appear inside double quotes, so leave as is
1737                                         $arg .= $token;
1738                                 }
1739                                 $iteration++;
1740                         }
1741                         // Double the backslashes before the end of the string, because
1742                         // we will soon add a quote
1743                         $m = array();
1744                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
1745                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
1746                         }
1747
1748                         // Add surrounding quotes
1749                         $retVal .= '"' . $arg . '"';
1750                 } else {
1751                         $retVal .= escapeshellarg( $arg );
1752                 }
1753         }
1754         return $retVal;
1755 }
1756
1757 /**
1758  * wfMerge attempts to merge differences between three texts.
1759  * Returns true for a clean merge and false for failure or a conflict.
1760  *
1761  * @param $old String
1762  * @param $mine String
1763  * @param $yours String
1764  * @param $result String
1765  * @return Bool
1766  */
1767 function wfMerge( $old, $mine, $yours, &$result ) {
1768         global $wgDiff3;
1769
1770         # This check may also protect against code injection in
1771         # case of broken installations.
1772         wfSuppressWarnings();
1773         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
1774         wfRestoreWarnings();
1775
1776         if( !$haveDiff3 ) {
1777                 wfDebug( "diff3 not found\n" );
1778                 return false;
1779         }
1780
1781         # Make temporary files
1782         $td = wfTempDir();
1783         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1784         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
1785         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
1786
1787         fwrite( $oldtextFile, $old );
1788         fclose( $oldtextFile );
1789         fwrite( $mytextFile, $mine );
1790         fclose( $mytextFile );
1791         fwrite( $yourtextFile, $yours );
1792         fclose( $yourtextFile );
1793
1794         # Check for a conflict
1795         $cmd = $wgDiff3 . ' -a --overlap-only ' .
1796                 wfEscapeShellArg( $mytextName ) . ' ' .
1797                 wfEscapeShellArg( $oldtextName ) . ' ' .
1798                 wfEscapeShellArg( $yourtextName );
1799         $handle = popen( $cmd, 'r' );
1800
1801         if( fgets( $handle, 1024 ) ) {
1802                 $conflict = true;
1803         } else {
1804                 $conflict = false;
1805         }
1806         pclose( $handle );
1807
1808         # Merge differences
1809         $cmd = $wgDiff3 . ' -a -e --merge ' .
1810                 wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
1811         $handle = popen( $cmd, 'r' );
1812         $result = '';
1813         do {
1814                 $data = fread( $handle, 8192 );
1815                 if ( strlen( $data ) == 0 ) {
1816                         break;
1817                 }
1818                 $result .= $data;
1819         } while ( true );
1820         pclose( $handle );
1821         unlink( $mytextName );
1822         unlink( $oldtextName );
1823         unlink( $yourtextName );
1824
1825         if ( $result === '' && $old !== '' && !$conflict ) {
1826                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
1827                 $conflict = true;
1828         }
1829         return !$conflict;
1830 }
1831
1832 /**
1833  * Returns unified plain-text diff of two texts.
1834  * Useful for machine processing of diffs.
1835  *
1836  * @param $before String: the text before the changes.
1837  * @param $after String: the text after the changes.
1838  * @param $params String: command-line options for the diff command.
1839  * @return String: unified diff of $before and $after
1840  */
1841 function wfDiff( $before, $after, $params = '-u' ) {
1842         if ( $before == $after ) {
1843                 return '';
1844         }
1845
1846         global $wgDiff;
1847         wfSuppressWarnings();
1848         $haveDiff = $wgDiff && file_exists( $wgDiff );
1849         wfRestoreWarnings();
1850
1851         # This check may also protect against code injection in
1852         # case of broken installations.
1853         if( !$haveDiff ) {
1854                 wfDebug( "diff executable not found\n" );
1855                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
1856                 $format = new UnifiedDiffFormatter();
1857                 return $format->format( $diffs );
1858         }
1859
1860         # Make temporary files
1861         $td = wfTempDir();
1862         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1863         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
1864
1865         fwrite( $oldtextFile, $before );
1866         fclose( $oldtextFile );
1867         fwrite( $newtextFile, $after );
1868         fclose( $newtextFile );
1869
1870         // Get the diff of the two files
1871         $cmd = "$wgDiff " . $params . ' ' . wfEscapeShellArg( $oldtextName, $newtextName );
1872
1873         $h = popen( $cmd, 'r' );
1874
1875         $diff = '';
1876
1877         do {
1878                 $data = fread( $h, 8192 );
1879                 if ( strlen( $data ) == 0 ) {
1880                         break;
1881                 }
1882                 $diff .= $data;
1883         } while ( true );
1884
1885         // Clean up
1886         pclose( $h );
1887         unlink( $oldtextName );
1888         unlink( $newtextName );
1889
1890         // Kill the --- and +++ lines. They're not useful.
1891         $diff_lines = explode( "\n", $diff );
1892         if ( strpos( $diff_lines[0], '---' ) === 0 ) {
1893                 unset( $diff_lines[0] );
1894         }
1895         if ( strpos( $diff_lines[1], '+++' ) === 0 ) {
1896                 unset( $diff_lines[1] );
1897         }
1898
1899         $diff = implode( "\n", $diff_lines );
1900
1901         return $diff;
1902 }
1903
1904 /**
1905  * A wrapper around the PHP function var_export().
1906  * Either print it or add it to the regular output ($wgOut).
1907  *
1908  * @param $var A PHP variable to dump.
1909  */
1910 function wfVarDump( $var ) {
1911         global $wgOut;
1912         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
1913         if ( headers_sent() || !isset( $wgOut ) || !is_object( $wgOut ) ) {
1914                 print $s;
1915         } else {
1916                 $wgOut->addHTML( $s );
1917         }
1918 }
1919
1920 /**
1921  * Provide a simple HTTP error.
1922  *
1923  * @param $code Int|String
1924  * @param $label String
1925  * @param $desc String
1926  */
1927 function wfHttpError( $code, $label, $desc ) {
1928         global $wgOut;
1929         $wgOut->disable();
1930         header( "HTTP/1.0 $code $label" );
1931         header( "Status: $code $label" );
1932         $wgOut->sendCacheControl();
1933
1934         header( 'Content-type: text/html; charset=utf-8' );
1935         print "<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">".
1936                 '<html><head><title>' .
1937                 htmlspecialchars( $label ) .
1938                 '</title></head><body><h1>' .
1939                 htmlspecialchars( $label ) .
1940                 '</h1><p>' .
1941                 nl2br( htmlspecialchars( $desc ) ) .
1942                 "</p></body></html>\n";
1943 }
1944
1945 /**
1946  * Clear away any user-level output buffers, discarding contents.
1947  *
1948  * Suitable for 'starting afresh', for instance when streaming
1949  * relatively large amounts of data without buffering, or wanting to
1950  * output image files without ob_gzhandler's compression.
1951  *
1952  * The optional $resetGzipEncoding parameter controls suppression of
1953  * the Content-Encoding header sent by ob_gzhandler; by default it
1954  * is left. See comments for wfClearOutputBuffers() for why it would
1955  * be used.
1956  *
1957  * Note that some PHP configuration options may add output buffer
1958  * layers which cannot be removed; these are left in place.
1959  *
1960  * @param $resetGzipEncoding Bool
1961  */
1962 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
1963         if( $resetGzipEncoding ) {
1964                 // Suppress Content-Encoding and Content-Length
1965                 // headers from 1.10+s wfOutputHandler
1966                 global $wgDisableOutputCompression;
1967                 $wgDisableOutputCompression = true;
1968         }
1969         while( $status = ob_get_status() ) {
1970                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
1971                         // Probably from zlib.output_compression or other
1972                         // PHP-internal setting which can't be removed.
1973                         //
1974                         // Give up, and hope the result doesn't break
1975                         // output behavior.
1976                         break;
1977                 }
1978                 if( !ob_end_clean() ) {
1979                         // Could not remove output buffer handler; abort now
1980                         // to avoid getting in some kind of infinite loop.
1981                         break;
1982                 }
1983                 if( $resetGzipEncoding ) {
1984                         if( $status['name'] == 'ob_gzhandler' ) {
1985                                 // Reset the 'Content-Encoding' field set by this handler
1986                                 // so we can start fresh.
1987                                 if ( function_exists( 'header_remove' ) ) {
1988                                         // Available since PHP 5.3.0
1989                                         header_remove( 'Content-Encoding' );
1990                                 } else {
1991                                         // We need to provide a valid content-coding. See bug 28069
1992                                         header( 'Content-Encoding: identity' );
1993                                 }
1994                                 break;
1995                         }
1996                 }
1997         }
1998 }
1999
2000 /**
2001  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
2002  *
2003  * Clear away output buffers, but keep the Content-Encoding header
2004  * produced by ob_gzhandler, if any.
2005  *
2006  * This should be used for HTTP 304 responses, where you need to
2007  * preserve the Content-Encoding header of the real result, but
2008  * also need to suppress the output of ob_gzhandler to keep to spec
2009  * and avoid breaking Firefox in rare cases where the headers and
2010  * body are broken over two packets.
2011  */
2012 function wfClearOutputBuffers() {
2013         wfResetOutputBuffers( false );
2014 }
2015
2016 /**
2017  * Converts an Accept-* header into an array mapping string values to quality
2018  * factors
2019  *
2020  * @param $accept String
2021  * @param $def String default
2022  * @return Array
2023  */
2024 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
2025         # No arg means accept anything (per HTTP spec)
2026         if( !$accept ) {
2027                 return array( $def => 1.0 );
2028         }
2029
2030         $prefs = array();
2031
2032         $parts = explode( ',', $accept );
2033
2034         foreach( $parts as $part ) {
2035                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
2036                 $values = explode( ';', trim( $part ) );
2037                 $match = array();
2038                 if ( count( $values ) == 1 ) {
2039                         $prefs[$values[0]] = 1.0;
2040                 } elseif ( preg_match( '/q\s*=\s*(\d*\.\d+)/', $values[1], $match ) ) {
2041                         $prefs[$values[0]] = floatval( $match[1] );
2042                 }
2043         }
2044
2045         return $prefs;
2046 }
2047
2048 /**
2049  * Checks if a given MIME type matches any of the keys in the given
2050  * array. Basic wildcards are accepted in the array keys.
2051  *
2052  * Returns the matching MIME type (or wildcard) if a match, otherwise
2053  * NULL if no match.
2054  *
2055  * @param $type String
2056  * @param $avail Array
2057  * @return string
2058  * @private
2059  */
2060 function mimeTypeMatch( $type, $avail ) {
2061         if( array_key_exists( $type, $avail ) ) {
2062                 return $type;
2063         } else {
2064                 $parts = explode( '/', $type );
2065                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
2066                         return $parts[0] . '/*';
2067                 } elseif( array_key_exists( '*/*', $avail ) ) {
2068                         return '*/*';
2069                 } else {
2070                         return null;
2071                 }
2072         }
2073 }
2074
2075 /**
2076  * Returns the 'best' match between a client's requested internet media types
2077  * and the server's list of available types. Each list should be an associative
2078  * array of type to preference (preference is a float between 0.0 and 1.0).
2079  * Wildcards in the types are acceptable.
2080  *
2081  * @param $cprefs Array: client's acceptable type list
2082  * @param $sprefs Array: server's offered types
2083  * @return string
2084  *
2085  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
2086  * XXX: generalize to negotiate other stuff
2087  */
2088 function wfNegotiateType( $cprefs, $sprefs ) {
2089         $combine = array();
2090
2091         foreach( array_keys($sprefs) as $type ) {
2092                 $parts = explode( '/', $type );
2093                 if( $parts[1] != '*' ) {
2094                         $ckey = mimeTypeMatch( $type, $cprefs );
2095                         if( $ckey ) {
2096                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
2097                         }
2098                 }
2099         }
2100
2101         foreach( array_keys( $cprefs ) as $type ) {
2102                 $parts = explode( '/', $type );
2103                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
2104                         $skey = mimeTypeMatch( $type, $sprefs );
2105                         if( $skey ) {
2106                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
2107                         }
2108                 }
2109         }
2110
2111         $bestq = 0;
2112         $besttype = null;
2113
2114         foreach( array_keys( $combine ) as $type ) {
2115                 if( $combine[$type] > $bestq ) {
2116                         $besttype = $type;
2117                         $bestq = $combine[$type];
2118                 }
2119         }
2120
2121         return $besttype;
2122 }
2123
2124 /**
2125  * Reference-counted warning suppression
2126  *
2127  * @param $end Bool
2128  */
2129 function wfSuppressWarnings( $end = false ) {
2130         static $suppressCount = 0;
2131         static $originalLevel = false;
2132
2133         if ( $end ) {
2134                 if ( $suppressCount ) {
2135                         --$suppressCount;
2136                         if ( !$suppressCount ) {
2137                                 error_reporting( $originalLevel );
2138                         }
2139                 }
2140         } else {
2141                 if ( !$suppressCount ) {
2142                         // E_DEPRECATED is undefined in PHP 5.2
2143                         if( !defined( 'E_DEPRECATED' ) ){
2144                                 define( 'E_DEPRECATED', 8192 );
2145                         }
2146                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE | E_USER_WARNING | E_USER_NOTICE | E_DEPRECATED ) );
2147                 }
2148                 ++$suppressCount;
2149         }
2150 }
2151
2152 /**
2153  * Restore error level to previous value
2154  */
2155 function wfRestoreWarnings() {
2156         wfSuppressWarnings( true );
2157 }
2158
2159 # Autodetect, convert and provide timestamps of various types
2160
2161 /**
2162  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
2163  */
2164 define( 'TS_UNIX', 0 );
2165
2166 /**
2167  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
2168  */
2169 define( 'TS_MW', 1 );
2170
2171 /**
2172  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
2173  */
2174 define( 'TS_DB', 2 );
2175
2176 /**
2177  * RFC 2822 format, for E-mail and HTTP headers
2178  */
2179 define( 'TS_RFC2822', 3 );
2180
2181 /**
2182  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
2183  *
2184  * This is used by Special:Export
2185  */
2186 define( 'TS_ISO_8601', 4 );
2187
2188 /**
2189  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
2190  *
2191  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
2192  *       DateTime tag and page 36 for the DateTimeOriginal and
2193  *       DateTimeDigitized tags.
2194  */
2195 define( 'TS_EXIF', 5 );
2196
2197 /**
2198  * Oracle format time.
2199  */
2200 define( 'TS_ORACLE', 6 );
2201
2202 /**
2203  * Postgres format time.
2204  */
2205 define( 'TS_POSTGRES', 7 );
2206
2207 /**
2208  * DB2 format time
2209  */
2210 define( 'TS_DB2', 8 );
2211
2212 /**
2213  * ISO 8601 basic format with no timezone: 19860209T200000Z.  This is used by ResourceLoader
2214  */
2215 define( 'TS_ISO_8601_BASIC', 9 );
2216
2217 /**
2218  * Get a timestamp string in one of various formats
2219  *
2220  * @param $outputtype Mixed: A timestamp in one of the supported formats, the
2221  *                    function will autodetect which format is supplied and act
2222  *                    accordingly.
2223  * @param $ts Mixed: the timestamp to convert or 0 for the current timestamp
2224  * @return Mixed: String / false The same date in the format specified in $outputtype or false
2225  */
2226 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
2227         $uts = 0;
2228         $da = array();
2229         $strtime = '';
2230
2231         if ( !$ts ) { // We want to catch 0, '', null... but not date strings starting with a letter.
2232                 $uts = time();
2233                 $strtime = "@$uts";
2234         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2235                 # TS_DB
2236         } elseif ( preg_match( '/^(\d{4}):(\d\d):(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2237                 # TS_EXIF
2238         } elseif ( preg_match( '/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/D', $ts, $da ) ) {
2239                 # TS_MW
2240         } elseif ( preg_match( '/^-?\d{1,13}$/D', $ts ) ) {
2241                 # TS_UNIX
2242                 $uts = $ts;
2243                 $strtime = "@$ts"; // Undocumented?
2244         } elseif ( preg_match( '/^\d{2}-\d{2}-\d{4} \d{2}:\d{2}:\d{2}.\d{6}$/', $ts ) ) {
2245                 # TS_ORACLE // session altered to DD-MM-YYYY HH24:MI:SS.FF6
2246                 $strtime = preg_replace( '/(\d\d)\.(\d\d)\.(\d\d)(\.(\d+))?/', "$1:$2:$3",
2247                                 str_replace( '+00:00', 'UTC', $ts ) );
2248         } elseif ( preg_match( '/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2249                 # TS_ISO_8601
2250         } elseif ( preg_match( '/^(\d{4})(\d{2})(\d{2})T(\d{2})(\d{2})(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2251                 #TS_ISO_8601_BASIC
2252         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d*[\+\- ](\d\d)$/', $ts, $da ) ) {
2253                 # TS_POSTGRES
2254         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d* GMT$/', $ts, $da ) ) {
2255                 # TS_POSTGRES
2256         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.\d\d\d$/',$ts,$da)) {
2257                 # TS_DB2
2258         } elseif ( preg_match( '/^[ \t\r\n]*([A-Z][a-z]{2},[ \t\r\n]*)?' . # Day of week
2259                                                         '\d\d?[ \t\r\n]*[A-Z][a-z]{2}[ \t\r\n]*\d{2}(?:\d{2})?' .  # dd Mon yyyy
2260                                                         '[ \t\r\n]*\d\d[ \t\r\n]*:[ \t\r\n]*\d\d[ \t\r\n]*:[ \t\r\n]*\d\d/S', $ts ) ) { # hh:mm:ss
2261                 # TS_RFC2822, accepting a trailing comment. See http://www.squid-cache.org/mail-archive/squid-users/200307/0122.html / r77171
2262                 # The regex is a superset of rfc2822 for readability
2263                 $strtime = strtok( $ts, ';' );
2264         } elseif ( preg_match( '/^[A-Z][a-z]{5,8}, \d\d-[A-Z][a-z]{2}-\d{2} \d\d:\d\d:\d\d/', $ts ) ) {
2265                 # TS_RFC850
2266                 $strtime = $ts;
2267         } elseif ( preg_match( '/^[A-Z][a-z]{2} [A-Z][a-z]{2} +\d{1,2} \d\d:\d\d:\d\d \d{4}/', $ts ) ) {
2268                 # asctime
2269                 $strtime = $ts;
2270         } else {
2271                 # Bogus value...
2272                 wfDebug("wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n");
2273
2274                 return false;
2275         }
2276
2277         static $formats = array(
2278                 TS_UNIX => 'U',
2279                 TS_MW => 'YmdHis',
2280                 TS_DB => 'Y-m-d H:i:s',
2281                 TS_ISO_8601 => 'Y-m-d\TH:i:s\Z',
2282                 TS_ISO_8601_BASIC => 'Ymd\THis\Z',
2283                 TS_EXIF => 'Y:m:d H:i:s', // This shouldn't ever be used, but is included for completeness
2284                 TS_RFC2822 => 'D, d M Y H:i:s',
2285                 TS_ORACLE => 'd-m-Y H:i:s.000000', // Was 'd-M-y h.i.s A' . ' +00:00' before r51500
2286                 TS_POSTGRES => 'Y-m-d H:i:s',
2287                 TS_DB2 => 'Y-m-d H:i:s',
2288         );
2289
2290         if ( !isset( $formats[$outputtype] ) ) {
2291                 throw new MWException( 'wfTimestamp() called with illegal output type.' );
2292         }
2293
2294         if ( function_exists( "date_create" ) ) {
2295                 if ( count( $da ) ) {
2296                         $ds = sprintf("%04d-%02d-%02dT%02d:%02d:%02d.00+00:00",
2297                                 (int)$da[1], (int)$da[2], (int)$da[3],
2298                                 (int)$da[4], (int)$da[5], (int)$da[6]);
2299
2300                         $d = date_create( $ds, new DateTimeZone( 'GMT' ) );
2301                 } elseif ( $strtime ) {
2302                         $d = date_create( $strtime, new DateTimeZone( 'GMT' ) );
2303                 } else {
2304                         return false;
2305                 }
2306
2307                 if ( !$d ) {
2308                         wfDebug("wfTimestamp() fed bogus time value: $outputtype; $ts\n");
2309                         return false;
2310                 }
2311
2312                 $output = $d->format( $formats[$outputtype] );
2313         } else {
2314                 if ( count( $da ) ) {
2315                         // Warning! gmmktime() acts oddly if the month or day is set to 0
2316                         // We may want to handle that explicitly at some point
2317                         $uts = gmmktime( (int)$da[4], (int)$da[5], (int)$da[6],
2318                                 (int)$da[2], (int)$da[3], (int)$da[1] );
2319                 } elseif ( $strtime ) {
2320                         $uts = strtotime( $strtime );
2321                 }
2322
2323                 if ( $uts === false ) {
2324                         wfDebug("wfTimestamp() can't parse the timestamp (non 32-bit time? Update php): $outputtype; $ts\n");
2325                         return false;
2326                 }
2327
2328                 if ( TS_UNIX == $outputtype ) {
2329                         return $uts;
2330                 }
2331                 $output = gmdate( $formats[$outputtype], $uts );
2332         }
2333
2334         if ( ( $outputtype == TS_RFC2822 ) || ( $outputtype == TS_POSTGRES ) ) {
2335                 $output .= ' GMT';
2336         }
2337
2338         return $output;
2339 }
2340
2341 /**
2342  * Return a formatted timestamp, or null if input is null.
2343  * For dealing with nullable timestamp columns in the database.
2344  *
2345  * @param $outputtype Integer
2346  * @param $ts String
2347  * @return String
2348  */
2349 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2350         if( is_null( $ts ) ) {
2351                 return null;
2352         } else {
2353                 return wfTimestamp( $outputtype, $ts );
2354         }
2355 }
2356
2357 /**
2358  * Convenience function; returns MediaWiki timestamp for the present time.
2359  *
2360  * @return string
2361  */
2362 function wfTimestampNow() {
2363         # return NOW
2364         return wfTimestamp( TS_MW, time() );
2365 }
2366
2367 /**
2368  * Check if the operating system is Windows
2369  *
2370  * @return Bool: true if it's Windows, False otherwise.
2371  */
2372 function wfIsWindows() {
2373         static $isWindows = null;
2374         if ( $isWindows === null ) {
2375                 $isWindows = substr( php_uname(), 0, 7 ) == 'Windows';
2376         }
2377         return $isWindows;
2378 }
2379
2380 /**
2381  * Check if we are running under HipHop
2382  *
2383  * @return Bool
2384  */
2385 function wfIsHipHop() {
2386         return function_exists( 'hphp_thread_set_warmup_enabled' );
2387 }
2388
2389 /**
2390  * Swap two variables
2391  *
2392  * @param $x Mixed
2393  * @param $y Mixed
2394  */
2395 function swap( &$x, &$y ) {
2396         $z = $x;
2397         $x = $y;
2398         $y = $z;
2399 }
2400
2401 /**
2402  * Tries to get the system directory for temporary files. The TMPDIR, TMP, and
2403  * TEMP environment variables are then checked in sequence, and if none are set
2404  * try sys_get_temp_dir() for PHP >= 5.2.1. All else fails, return /tmp for Unix
2405  * or C:\Windows\Temp for Windows and hope for the best.
2406  * It is common to call it with tempnam().
2407  *
2408  * NOTE: When possible, use instead the tmpfile() function to create
2409  * temporary files to avoid race conditions on file creation, etc.
2410  *
2411  * @return String
2412  */
2413 function wfTempDir() {
2414         foreach( array( 'TMPDIR', 'TMP', 'TEMP' ) as $var ) {
2415                 $tmp = getenv( $var );
2416                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
2417                         return $tmp;
2418                 }
2419         }
2420         if( function_exists( 'sys_get_temp_dir' ) ) {
2421                 return sys_get_temp_dir();
2422         }
2423         # Usual defaults
2424         return wfIsWindows() ? 'C:\Windows\Temp' : '/tmp';
2425 }
2426
2427 /**
2428  * Make directory, and make all parent directories if they don't exist
2429  *
2430  * @param $dir String: full path to directory to create
2431  * @param $mode Integer: chmod value to use, default is $wgDirectoryMode
2432  * @param $caller String: optional caller param for debugging.
2433  * @return bool
2434  */
2435 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2436         global $wgDirectoryMode;
2437
2438         if ( !is_null( $caller ) ) {
2439                 wfDebug( "$caller: called wfMkdirParents($dir)" );
2440         }
2441
2442         if( strval( $dir ) === '' || file_exists( $dir ) ) {
2443                 return true;
2444         }
2445
2446         $dir = str_replace( array( '\\', '/' ), DIRECTORY_SEPARATOR, $dir );
2447
2448         if ( is_null( $mode ) ) {
2449                 $mode = $wgDirectoryMode;
2450         }
2451
2452         // Turn off the normal warning, we're doing our own below
2453         wfSuppressWarnings();
2454         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2455         wfRestoreWarnings();
2456
2457         if( !$ok ) {
2458                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2459                 trigger_error( __FUNCTION__ . ": failed to mkdir \"$dir\" mode $mode", E_USER_WARNING );
2460         }
2461         return $ok;
2462 }
2463
2464 /**
2465  * Increment a statistics counter
2466  *
2467  * @param $key String
2468  * @param $count Int
2469  */
2470 function wfIncrStats( $key, $count = 1 ) {
2471         global $wgStatsMethod;
2472
2473         $count = intval( $count );
2474
2475         if( $wgStatsMethod == 'udp' ) {
2476                 global $wgUDPProfilerHost, $wgUDPProfilerPort, $wgDBname, $wgAggregateStatsID;
2477                 static $socket;
2478
2479                 $id = $wgAggregateStatsID !== false ? $wgAggregateStatsID : $wgDBname;
2480
2481                 if ( !$socket ) {
2482                         $socket = socket_create( AF_INET, SOCK_DGRAM, SOL_UDP );
2483                         $statline = "stats/{$id} - {$count} 1 1 1 1 -total\n";
2484                         socket_sendto(
2485                                 $socket,
2486                                 $statline,
2487                                 strlen( $statline ),
2488                                 0,
2489                                 $wgUDPProfilerHost,
2490                                 $wgUDPProfilerPort
2491                         );
2492                 }
2493                 $statline = "stats/{$id} - {$count} 1 1 1 1 {$key}\n";
2494                 wfSuppressWarnings();
2495                 socket_sendto(
2496                         $socket,
2497                         $statline,
2498                         strlen( $statline ),
2499                         0,
2500                         $wgUDPProfilerHost,
2501                         $wgUDPProfilerPort
2502                 );
2503                 wfRestoreWarnings();
2504         } elseif( $wgStatsMethod == 'cache' ) {
2505                 global $wgMemc;
2506                 $key = wfMemcKey( 'stats', $key );
2507                 if ( is_null( $wgMemc->incr( $key, $count ) ) ) {
2508                         $wgMemc->add( $key, $count );
2509                 }
2510         } else {
2511                 // Disabled
2512         }
2513 }
2514
2515 /**
2516  * @param $nr Mixed: the number to format
2517  * @param $acc Integer: the number of digits after the decimal point, default 2
2518  * @param $round Boolean: whether or not to round the value, default true
2519  * @return float
2520  */
2521 function wfPercent( $nr, $acc = 2, $round = true ) {
2522         $ret = sprintf( "%.${acc}f", $nr );
2523         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2524 }
2525
2526 /**
2527  * Find out whether or not a mixed variable exists in a string
2528  *
2529  * @param $needle String
2530  * @param $str String
2531  * @param $insensitive Boolean
2532  * @return Boolean
2533  */
2534 function in_string( $needle, $str, $insensitive = false ) {
2535         $func = 'strpos';
2536         if( $insensitive ) $func = 'stripos';
2537
2538         return $func( $str, $needle ) !== false;
2539 }
2540
2541 /**
2542  * Make a list item, used by various special pages
2543  *
2544  * @param $page String Page link
2545  * @param $details String Text between brackets
2546  * @param $oppositedm Boolean   Add the direction mark opposite to your
2547  *                                                              language, to display text properly
2548  * @return String
2549  */
2550 function wfSpecialList( $page, $details, $oppositedm = true ) {
2551         global $wgLang;
2552         $dirmark = ( $oppositedm ? $wgLang->getDirMark( true ) : '' ) .
2553                 $wgLang->getDirMark();
2554         $details = $details ? $dirmark . " ($details)" : '';
2555         return $page . $details;
2556 }
2557
2558 /**
2559  * Safety wrapper around ini_get() for boolean settings.
2560  * The values returned from ini_get() are pre-normalized for settings
2561  * set via php.ini or php_flag/php_admin_flag... but *not*
2562  * for those set via php_value/php_admin_value.
2563  *
2564  * It's fairly common for people to use php_value instead of php_flag,
2565  * which can leave you with an 'off' setting giving a false positive
2566  * for code that just takes the ini_get() return value as a boolean.
2567  *
2568  * To make things extra interesting, setting via php_value accepts
2569  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2570  * Unrecognized values go false... again opposite PHP's own coercion
2571  * from string to bool.
2572  *
2573  * Luckily, 'properly' set settings will always come back as '0' or '1',
2574  * so we only have to worry about them and the 'improper' settings.
2575  *
2576  * I frickin' hate PHP... :P
2577  *
2578  * @param $setting String
2579  * @return Bool
2580  */
2581 function wfIniGetBool( $setting ) {
2582         $val = ini_get( $setting );
2583         // 'on' and 'true' can't have whitespace around them, but '1' can.
2584         return strtolower( $val ) == 'on'
2585                 || strtolower( $val ) == 'true'
2586                 || strtolower( $val ) == 'yes'
2587                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2588 }
2589
2590 /**
2591  * Wrapper function for PHP's dl(). This doesn't work in most situations from
2592  * PHP 5.3 onward, and is usually disabled in shared environments anyway.
2593  *
2594  * @param $extension String A PHP extension. The file suffix (.so or .dll)
2595  *                          should be omitted
2596  * @param $fileName String Name of the library, if not $extension.suffix
2597  * @return Bool - Whether or not the extension is loaded
2598  */
2599 function wfDl( $extension, $fileName = null ) {
2600         if( extension_loaded( $extension ) ) {
2601                 return true;
2602         }
2603
2604         $canDl = false;
2605         $sapi = php_sapi_name();
2606         if( version_compare( PHP_VERSION, '5.3.0', '<' ) ||
2607                 $sapi == 'cli' || $sapi == 'cgi' || $sapi == 'embed' )
2608         {
2609                 $canDl = ( function_exists( 'dl' ) && is_callable( 'dl' )
2610                 && wfIniGetBool( 'enable_dl' ) && !wfIniGetBool( 'safe_mode' ) );
2611         }
2612
2613         if( $canDl ) {
2614                 $fileName = $fileName ? $fileName : $extension;
2615                 if( wfIsWindows() ) {
2616                         $fileName = 'php_' . $fileName;
2617                 }
2618                 wfSuppressWarnings();
2619                 dl( $fileName . '.' . PHP_SHLIB_SUFFIX );
2620                 wfRestoreWarnings();
2621         }
2622         return extension_loaded( $extension );
2623 }
2624
2625 /**
2626  * Execute a shell command, with time and memory limits mirrored from the PHP
2627  * configuration if supported.
2628  * @param $cmd String Command line, properly escaped for shell.
2629  * @param &$retval optional, will receive the program's exit code.
2630  *                 (non-zero is usually failure)
2631  * @param $environ Array optional environment variables which should be
2632  *                 added to the executed command environment.
2633  * @return collected stdout as a string (trailing newlines stripped)
2634  */
2635 function wfShellExec( $cmd, &$retval = null, $environ = array() ) {
2636         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize, $wgMaxShellTime;
2637
2638         static $disabled;
2639         if ( is_null( $disabled ) ) {
2640                 $disabled = false;
2641                 if( wfIniGetBool( 'safe_mode' ) ) {
2642                         wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
2643                         $disabled = 'safemode';
2644                 } else {
2645                         $functions = explode( ',', ini_get( 'disable_functions' ) );
2646                         $functions = array_map( 'trim', $functions );
2647                         $functions = array_map( 'strtolower', $functions );
2648                         if ( in_array( 'passthru', $functions ) ) {
2649                                 wfDebug( "passthru is in disabled_functions\n" );
2650                                 $disabled = 'passthru';
2651                         }
2652                 }
2653         }
2654         if ( $disabled ) {
2655                 $retval = 1;
2656                 return $disabled == 'safemode' ?
2657                         'Unable to run external programs in safe mode.' :
2658                         'Unable to run external programs, passthru() is disabled.';
2659         }
2660
2661         wfInitShellLocale();
2662
2663         $envcmd = '';
2664         foreach( $environ as $k => $v ) {
2665                 if ( wfIsWindows() ) {
2666                         /* Surrounding a set in quotes (method used by wfEscapeShellArg) makes the quotes themselves
2667                          * appear in the environment variable, so we must use carat escaping as documented in
2668                          * http://technet.microsoft.com/en-us/library/cc723564.aspx
2669                          * Note however that the quote isn't listed there, but is needed, and the parentheses
2670                          * are listed there but doesn't appear to need it.
2671                          */
2672                         $envcmd .= "set $k=" . preg_replace( '/([&|()<>^"])/', '^\\1', $v ) . '&& ';
2673                 } else {
2674                         /* Assume this is a POSIX shell, thus required to accept variable assignments before the command
2675                          * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_09_01
2676                          */
2677                         $envcmd .= "$k=" . escapeshellarg( $v ) . ' ';
2678                 }
2679         }
2680         $cmd = $envcmd . $cmd;
2681
2682         if ( wfIsWindows() ) {
2683                 if ( version_compare( PHP_VERSION, '5.3.0', '<' ) && /* Fixed in 5.3.0 :) */
2684                         ( version_compare( PHP_VERSION, '5.2.1', '>=' ) || php_uname( 's' ) == 'Windows NT' ) )
2685                 {
2686                         # Hack to work around PHP's flawed invocation of cmd.exe
2687                         # http://news.php.net/php.internals/21796
2688                         # Windows 9x doesn't accept any kind of quotes
2689                         $cmd = '"' . $cmd . '"';
2690                 }
2691         } elseif ( php_uname( 's' ) == 'Linux' ) {
2692                 $time = intval( $wgMaxShellTime );
2693                 $mem = intval( $wgMaxShellMemory );
2694                 $filesize = intval( $wgMaxShellFileSize );
2695
2696                 if ( $time > 0 && $mem > 0 ) {
2697                         $script = "$IP/bin/ulimit4.sh";
2698                         if ( is_executable( $script ) ) {
2699                                 $cmd = '/bin/bash ' . escapeshellarg( $script ) . " $time $mem $filesize " . escapeshellarg( $cmd );
2700                         }
2701                 }
2702         }
2703         wfDebug( "wfShellExec: $cmd\n" );
2704
2705         $retval = 1; // error by default?
2706         ob_start();
2707         passthru( $cmd, $retval );
2708         $output = ob_get_contents();
2709         ob_end_clean();
2710
2711         if ( $retval == 127 ) {
2712                 wfDebugLog( 'exec', "Possibly missing executable file: $cmd\n" );
2713         }
2714         return $output;
2715 }
2716
2717 /**
2718  * Workaround for http://bugs.php.net/bug.php?id=45132
2719  * escapeshellarg() destroys non-ASCII characters if LANG is not a UTF-8 locale
2720  */
2721 function wfInitShellLocale() {
2722         static $done = false;
2723         if ( $done ) {
2724                 return;
2725         }
2726         $done = true;
2727         global $wgShellLocale;
2728         if ( !wfIniGetBool( 'safe_mode' ) ) {
2729                 putenv( "LC_CTYPE=$wgShellLocale" );
2730                 setlocale( LC_CTYPE, $wgShellLocale );
2731         }
2732 }
2733
2734 /**
2735  * This function works like "use VERSION" in Perl, the program will die with a
2736  * backtrace if the current version of PHP is less than the version provided
2737  *
2738  * This is useful for extensions which due to their nature are not kept in sync
2739  * with releases, and might depend on other versions of PHP than the main code
2740  *
2741  * Note: PHP might die due to parsing errors in some cases before it ever
2742  *       manages to call this function, such is life
2743  *
2744  * @see perldoc -f use
2745  *
2746  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2747  *                 a float
2748  */
2749 function wfUsePHP( $req_ver ) {
2750         $php_ver = PHP_VERSION;
2751
2752         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
2753                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
2754         }
2755 }
2756
2757 /**
2758  * This function works like "use VERSION" in Perl except it checks the version
2759  * of MediaWiki, the program will die with a backtrace if the current version
2760  * of MediaWiki is less than the version provided.
2761  *
2762  * This is useful for extensions which due to their nature are not kept in sync
2763  * with releases
2764  *
2765  * @see perldoc -f use
2766  *
2767  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2768  *                 a float
2769  */
2770 function wfUseMW( $req_ver ) {
2771         global $wgVersion;
2772
2773         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
2774                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
2775         }
2776 }
2777
2778 /**
2779  * Return the final portion of a pathname.
2780  * Reimplemented because PHP5's basename() is buggy with multibyte text.
2781  * http://bugs.php.net/bug.php?id=33898
2782  *
2783  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
2784  * We'll consider it so always, as we don't want \s in our Unix paths either.
2785  *
2786  * @param $path String
2787  * @param $suffix String: to remove if present
2788  * @return String
2789  */
2790 function wfBaseName( $path, $suffix = '' ) {
2791         $encSuffix = ( $suffix == '' )
2792                 ? ''
2793                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
2794         $matches = array();
2795         if( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2796                 return $matches[1];
2797         } else {
2798                 return '';
2799         }
2800 }
2801
2802 /**
2803  * Generate a relative path name to the given file.
2804  * May explode on non-matching case-insensitive paths,
2805  * funky symlinks, etc.
2806  *
2807  * @param $path String: absolute destination path including target filename
2808  * @param $from String: Absolute source path, directory only
2809  * @return String
2810  */
2811 function wfRelativePath( $path, $from ) {
2812         // Normalize mixed input on Windows...
2813         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2814         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2815
2816         // Trim trailing slashes -- fix for drive root
2817         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2818         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2819
2820         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2821         $against = explode( DIRECTORY_SEPARATOR, $from );
2822
2823         if( $pieces[0] !== $against[0] ) {
2824                 // Non-matching Windows drive letters?
2825                 // Return a full path.
2826                 return $path;
2827         }
2828
2829         // Trim off common prefix
2830         while( count( $pieces ) && count( $against )
2831                 && $pieces[0] == $against[0] ) {
2832                 array_shift( $pieces );
2833                 array_shift( $against );
2834         }
2835
2836         // relative dots to bump us to the parent
2837         while( count( $against ) ) {
2838                 array_unshift( $pieces, '..' );
2839                 array_shift( $against );
2840         }
2841
2842         array_push( $pieces, wfBaseName( $path ) );
2843
2844         return implode( DIRECTORY_SEPARATOR, $pieces );
2845 }
2846
2847 /**
2848  * Do any deferred updates and clear the list
2849  *
2850  * @param $commit String: set to 'commit' to commit after every update to
2851  *                prevent lock contention
2852  */
2853 function wfDoUpdates( $commit = '' ) {
2854         global $wgDeferredUpdateList;
2855
2856         wfProfileIn( __METHOD__ );
2857
2858         // No need to get master connections in case of empty updates array
2859         if ( !count( $wgDeferredUpdateList ) ) {
2860                 wfProfileOut( __METHOD__ );
2861                 return;
2862         }
2863
2864         $doCommit = $commit == 'commit';
2865         if ( $doCommit ) {
2866                 $dbw = wfGetDB( DB_MASTER );
2867         }
2868
2869         foreach ( $wgDeferredUpdateList as $update ) {
2870                 $update->doUpdate();
2871
2872                 if ( $doCommit && $dbw->trxLevel() ) {
2873                         $dbw->commit();
2874                 }
2875         }
2876
2877         $wgDeferredUpdateList = array();
2878         wfProfileOut( __METHOD__ );
2879 }
2880
2881 /**
2882  * Convert an arbitrarily-long digit string from one numeric base
2883  * to another, optionally zero-padding to a minimum column width.
2884  *
2885  * Supports base 2 through 36; digit values 10-36 are represented
2886  * as lowercase letters a-z. Input is case-insensitive.
2887  *
2888  * @param $input String: of digits
2889  * @param $sourceBase Integer: 2-36
2890  * @param $destBase Integer: 2-36
2891  * @param $pad Integer: 1 or greater
2892  * @param $lowercase Boolean
2893  * @return String or false on invalid input
2894  */
2895 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1, $lowercase = true ) {
2896         $input = strval( $input );
2897         if( $sourceBase < 2 ||
2898                 $sourceBase > 36 ||
2899                 $destBase < 2 ||
2900                 $destBase > 36 ||
2901                 $pad < 1 ||
2902                 $sourceBase != intval( $sourceBase ) ||
2903                 $destBase != intval( $destBase ) ||
2904                 $pad != intval( $pad ) ||
2905                 !is_string( $input ) ||
2906                 $input == '' ) {
2907                 return false;
2908         }
2909         $digitChars = ( $lowercase ) ? '0123456789abcdefghijklmnopqrstuvwxyz' : '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
2910         $inDigits = array();
2911         $outChars = '';
2912
2913         // Decode and validate input string
2914         $input = strtolower( $input );
2915         for( $i = 0; $i < strlen( $input ); $i++ ) {
2916                 $n = strpos( $digitChars, $input[$i] );
2917                 if( $n === false || $n > $sourceBase ) {
2918                         return false;
2919                 }
2920                 $inDigits[] = $n;
2921         }
2922
2923         // Iterate over the input, modulo-ing out an output digit
2924         // at a time until input is gone.
2925         while( count( $inDigits ) ) {
2926                 $work = 0;
2927                 $workDigits = array();
2928
2929                 // Long division...
2930                 foreach( $inDigits as $digit ) {
2931                         $work *= $sourceBase;
2932                         $work += $digit;
2933
2934                         if( $work < $destBase ) {
2935                                 // Gonna need to pull another digit.
2936                                 if( count( $workDigits ) ) {
2937                                         // Avoid zero-padding; this lets us find
2938                                         // the end of the input very easily when
2939                                         // length drops to zero.
2940                                         $workDigits[] = 0;
2941                                 }
2942                         } else {
2943                                 // Finally! Actual division!
2944                                 $workDigits[] = intval( $work / $destBase );
2945
2946                                 // Isn't it annoying that most programming languages
2947                                 // don't have a single divide-and-remainder operator,
2948                                 // even though the CPU implements it that way?
2949                                 $work = $work % $destBase;
2950                         }
2951                 }
2952
2953                 // All that division leaves us with a remainder,
2954                 // which is conveniently our next output digit.
2955                 $outChars .= $digitChars[$work];
2956
2957                 // And we continue!
2958                 $inDigits = $workDigits;
2959         }
2960
2961         while( strlen( $outChars ) < $pad ) {
2962                 $outChars .= '0';
2963         }
2964
2965         return strrev( $outChars );
2966 }
2967
2968 /**
2969  * Create an object with a given name and an array of construct parameters
2970  *
2971  * @param $name String
2972  * @param $p Array: parameters
2973  * @deprecated since 1.18, warnings in 1.18, removal in 1.20
2974  */
2975 function wfCreateObject( $name, $p ) {
2976         wfDeprecated( __FUNCTION__ );
2977         return MWFunction::newObj( $name, $p );
2978 }
2979
2980 function wfHttpOnlySafe() {
2981         global $wgHttpOnlyBlacklist;
2982
2983         if( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
2984                 foreach( $wgHttpOnlyBlacklist as $regex ) {
2985                         if( preg_match( $regex, $_SERVER['HTTP_USER_AGENT'] ) ) {
2986                                 return false;
2987                         }
2988                 }
2989         }
2990
2991         return true;
2992 }
2993
2994 /**
2995  * Initialise php session
2996  *
2997  * @param $sessionId Bool
2998  */
2999 function wfSetupSession( $sessionId = false ) {
3000         global $wgSessionsInMemcached, $wgCookiePath, $wgCookieDomain,
3001                         $wgCookieSecure, $wgCookieHttpOnly, $wgSessionHandler;
3002         if( $wgSessionsInMemcached ) {
3003                 if ( !defined( 'MW_COMPILED' ) ) {
3004                         global $IP;
3005                         require_once( "$IP/includes/cache/MemcachedSessions.php" );
3006                 }
3007                 session_set_save_handler( 'memsess_open', 'memsess_close', 'memsess_read',
3008                         'memsess_write', 'memsess_destroy', 'memsess_gc' );
3009
3010                 // It's necessary to register a shutdown function to call session_write_close(),
3011                 // because by the time the request shutdown function for the session module is
3012                 // called, $wgMemc has already been destroyed. Shutdown functions registered
3013                 // this way are called before object destruction.
3014                 register_shutdown_function( 'memsess_write_close' );
3015         } elseif( $wgSessionHandler && $wgSessionHandler != ini_get( 'session.save_handler' ) ) {
3016                 # Only set this if $wgSessionHandler isn't null and session.save_handler
3017                 # hasn't already been set to the desired value (that causes errors)
3018                 ini_set( 'session.save_handler', $wgSessionHandler );
3019         }
3020         $httpOnlySafe = wfHttpOnlySafe() && $wgCookieHttpOnly;
3021         wfDebugLog( 'cookie',
3022                 'session_set_cookie_params: "' . implode( '", "',
3023                         array(
3024                                 0,
3025                                 $wgCookiePath,
3026                                 $wgCookieDomain,
3027                                 $wgCookieSecure,
3028                                 $httpOnlySafe ) ) . '"' );
3029         session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $httpOnlySafe );
3030         session_cache_limiter( 'private, must-revalidate' );
3031         if ( $sessionId ) {
3032                 session_id( $sessionId );
3033         }
3034         wfSuppressWarnings();
3035         session_start();
3036         wfRestoreWarnings();
3037 }
3038
3039 /**
3040  * Get an object from the precompiled serialized directory
3041  *
3042  * @param $name String
3043  * @return Mixed: the variable on success, false on failure
3044  */
3045 function wfGetPrecompiledData( $name ) {
3046         global $IP;
3047
3048         $file = "$IP/serialized/$name";
3049         if ( file_exists( $file ) ) {
3050                 $blob = file_get_contents( $file );
3051                 if ( $blob ) {
3052                         return unserialize( $blob );
3053                 }
3054         }
3055         return false;
3056 }
3057
3058 /**
3059  * Get a cache key
3060  *
3061  * @param varargs
3062  * @return String
3063  */
3064 function wfMemcKey( /*... */ ) {
3065         $args = func_get_args();
3066         $key = wfWikiID() . ':' . implode( ':', $args );
3067         $key = str_replace( ' ', '_', $key );
3068         return $key;
3069 }
3070
3071 /**
3072  * Get a cache key for a foreign DB
3073  *
3074  * @param $db String
3075  * @param $prefix String
3076  * @param varargs String
3077  * @return String
3078  */
3079 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
3080         $args = array_slice( func_get_args(), 2 );
3081         if ( $prefix ) {
3082                 $key = "$db-$prefix:" . implode( ':', $args );
3083         } else {
3084                 $key = $db . ':' . implode( ':', $args );
3085         }
3086         return $key;
3087 }
3088
3089 /**
3090  * Get an ASCII string identifying this wiki
3091  * This is used as a prefix in memcached keys
3092  *
3093  * @return String
3094  */
3095 function wfWikiID() {
3096         global $wgDBprefix, $wgDBname;
3097         if ( $wgDBprefix ) {
3098                 return "$wgDBname-$wgDBprefix";
3099         } else {
3100                 return $wgDBname;
3101         }
3102 }
3103
3104 /**
3105  * Split a wiki ID into DB name and table prefix
3106  *
3107  * @param $wiki String
3108  * @param $bits String
3109  */
3110 function wfSplitWikiID( $wiki ) {
3111         $bits = explode( '-', $wiki, 2 );
3112         if ( count( $bits ) < 2 ) {
3113                 $bits[] = '';
3114         }
3115         return $bits;
3116 }
3117
3118 /**
3119  * Get a Database object.
3120  *
3121  * @param $db Integer: index of the connection to get. May be DB_MASTER for the
3122  *            master (for write queries), DB_SLAVE for potentially lagged read
3123  *            queries, or an integer >= 0 for a particular server.
3124  *
3125  * @param $groups Mixed: query groups. An array of group names that this query
3126  *                belongs to. May contain a single string if the query is only
3127  *                in one group.
3128  *
3129  * @param $wiki String: the wiki ID, or false for the current wiki
3130  *
3131  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
3132  * will always return the same object, unless the underlying connection or load
3133  * balancer is manually destroyed.
3134  *
3135  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
3136  * updater to ensure that a proper database is being updated.
3137  *
3138  * @return DatabaseBase
3139  */
3140 function &wfGetDB( $db, $groups = array(), $wiki = false ) {
3141         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
3142 }
3143
3144 /**
3145  * Get a load balancer object.
3146  *
3147  * @param $wiki String: wiki ID, or false for the current wiki
3148  * @return LoadBalancer
3149  */
3150 function wfGetLB( $wiki = false ) {
3151         return wfGetLBFactory()->getMainLB( $wiki );
3152 }
3153
3154 /**
3155  * Get the load balancer factory object
3156  *
3157  * @return LBFactory
3158  */
3159 function &wfGetLBFactory() {
3160         return LBFactory::singleton();
3161 }
3162
3163 /**
3164  * Find a file.
3165  * Shortcut for RepoGroup::singleton()->findFile()
3166  *
3167  * @param $title String or Title object
3168  * @param $options Associative array of options:
3169  *     time:           requested time for an archived image, or false for the
3170  *                     current version. An image object will be returned which was
3171  *                     created at the specified time.
3172  *
3173  *     ignoreRedirect: If true, do not follow file redirects
3174  *
3175  *     private:        If true, return restricted (deleted) files if the current
3176  *                     user is allowed to view them. Otherwise, such files will not
3177  *                     be found.
3178  *
3179  *     bypassCache:    If true, do not use the process-local cache of File objects
3180  *
3181  * @return File, or false if the file does not exist
3182  */
3183 function wfFindFile( $title, $options = array() ) {
3184         return RepoGroup::singleton()->findFile( $title, $options );
3185 }
3186
3187 /**
3188  * Get an object referring to a locally registered file.
3189  * Returns a valid placeholder object if the file does not exist.
3190  *
3191  * @param $title Title or String
3192  * @return File, or null if passed an invalid Title
3193  */
3194 function wfLocalFile( $title ) {
3195         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
3196 }
3197
3198 /**
3199  * Should low-performance queries be disabled?
3200  *
3201  * @return Boolean
3202  * @codeCoverageIgnore
3203  */
3204 function wfQueriesMustScale() {
3205         global $wgMiserMode;
3206         return $wgMiserMode
3207                 || ( SiteStats::pages() > 100000
3208                 && SiteStats::edits() > 1000000
3209                 && SiteStats::users() > 10000 );
3210 }
3211
3212 /**
3213  * Get the path to a specified script file, respecting file
3214  * extensions; this is a wrapper around $wgScriptExtension etc.
3215  *
3216  * @param $script String: script filename, sans extension
3217  * @return String
3218  */
3219 function wfScript( $script = 'index' ) {
3220         global $wgScriptPath, $wgScriptExtension;
3221         return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
3222 }
3223
3224 /**
3225  * Get the script URL.
3226  *
3227  * @return script URL
3228  */
3229 function wfGetScriptUrl() {
3230         if( isset( $_SERVER['SCRIPT_NAME'] ) ) {
3231                 #
3232                 # as it was called, minus the query string.
3233                 #
3234                 # Some sites use Apache rewrite rules to handle subdomains,
3235                 # and have PHP set up in a weird way that causes PHP_SELF
3236                 # to contain the rewritten URL instead of the one that the
3237                 # outside world sees.
3238                 #
3239                 # If in this mode, use SCRIPT_URL instead, which mod_rewrite
3240                 # provides containing the "before" URL.
3241                 return $_SERVER['SCRIPT_NAME'];
3242         } else {
3243                 return $_SERVER['URL'];
3244         }
3245 }
3246
3247 /**
3248  * Convenience function converts boolean values into "true"
3249  * or "false" (string) values
3250  *
3251  * @param $value Boolean
3252  * @return String
3253  */
3254 function wfBoolToStr( $value ) {
3255         return $value ? 'true' : 'false';
3256 }
3257
3258 /**
3259  * Load an extension messages file
3260  *
3261  * @deprecated since 1.16, warnings in 1.18, remove in 1.20
3262  * @codeCoverageIgnore
3263  */
3264 function wfLoadExtensionMessages() {
3265         wfDeprecated( __FUNCTION__ );
3266 }
3267
3268 /**
3269  * Get a platform-independent path to the null file, e.g. /dev/null
3270  *
3271  * @return string
3272  */
3273 function wfGetNull() {
3274         return wfIsWindows()
3275                 ? 'NUL'
3276                 : '/dev/null';
3277 }
3278
3279 /**
3280  * Throws a warning that $function is deprecated
3281  *
3282  * @param $function String
3283  * @return null
3284  */
3285 function wfDeprecated( $function ) {
3286         static $functionsWarned = array();
3287         if ( !isset( $functionsWarned[$function] ) ) {
3288                 $functionsWarned[$function] = true;
3289                 wfWarn( "Use of $function is deprecated.", 2 );
3290         }
3291 }
3292
3293 /**
3294  * Send a warning either to the debug log or in a PHP error depending on
3295  * $wgDevelopmentWarnings
3296  *
3297  * @param $msg String: message to send
3298  * @param $callerOffset Integer: number of items to go back in the backtrace to
3299  *        find the correct caller (1 = function calling wfWarn, ...)
3300  * @param $level Integer: PHP error level; only used when $wgDevelopmentWarnings
3301  *        is true
3302  */
3303 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
3304         global $wgDevelopmentWarnings;
3305
3306         $callers = wfDebugBacktrace();
3307         if ( isset( $callers[$callerOffset + 1] ) ) {
3308                 $callerfunc = $callers[$callerOffset + 1];
3309                 $callerfile = $callers[$callerOffset];
3310                 if ( isset( $callerfile['file'] ) && isset( $callerfile['line'] ) ) {
3311                         $file = $callerfile['file'] . ' at line ' . $callerfile['line'];
3312                 } else {
3313                         $file = '(internal function)';
3314                 }
3315                 $func = '';
3316                 if ( isset( $callerfunc['class'] ) ) {
3317                         $func .= $callerfunc['class'] . '::';
3318                 }
3319                 if ( isset( $callerfunc['function'] ) ) {
3320                         $func .= $callerfunc['function'];
3321                 }
3322                 $msg .= " [Called from $func in $file]";
3323         }
3324
3325         if ( $wgDevelopmentWarnings ) {
3326                 trigger_error( $msg, $level );
3327         } else {
3328                 wfDebug( "$msg\n" );
3329         }
3330 }
3331
3332 /**
3333  * Modern version of wfWaitForSlaves(). Instead of looking at replication lag
3334  * and waiting for it to go down, this waits for the slaves to catch up to the
3335  * master position. Use this when updating very large numbers of rows, as
3336  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
3337  * a no-op if there are no slaves.
3338  *
3339  * @param $maxLag Integer (deprecated)
3340  * @param $wiki mixed Wiki identifier accepted by wfGetLB
3341  * @return null
3342  */
3343 function wfWaitForSlaves( $maxLag = false, $wiki = false ) {
3344         $lb = wfGetLB( $wiki );
3345         // bug 27975 - Don't try to wait for slaves if there are none
3346         // Prevents permission error when getting master position
3347         if ( $lb->getServerCount() > 1 ) {
3348                 $dbw = $lb->getConnection( DB_MASTER );
3349                 $pos = $dbw->getMasterPos();
3350                 $lb->waitForAll( $pos );
3351         }
3352 }
3353
3354 /**
3355  * Used to be used for outputting text in the installer/updater
3356  * @deprecated since 1.18, warnings in 1.18, remove in 1.20
3357  */
3358 function wfOut( $s ) {
3359         wfDeprecated( __METHOD__ );
3360         global $wgCommandLineMode;
3361         if ( $wgCommandLineMode ) {
3362                 echo $s;
3363         } else {
3364                 echo htmlspecialchars( $s );
3365         }
3366         flush();
3367 }
3368
3369 /**
3370  * Count down from $n to zero on the terminal, with a one-second pause
3371  * between showing each number. For use in command-line scripts.
3372  * @codeCoverageIgnore
3373  */
3374 function wfCountDown( $n ) {
3375         for ( $i = $n; $i >= 0; $i-- ) {
3376                 if ( $i != $n ) {
3377                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3378                 }
3379                 echo $i;
3380                 flush();
3381                 if ( $i ) {
3382                         sleep( 1 );
3383                 }
3384         }
3385         echo "\n";
3386 }
3387
3388 /**
3389  * Generate a random 32-character hexadecimal token.
3390  * @param $salt Mixed: some sort of salt, if necessary, to add to random
3391  *              characters before hashing.
3392  * @return string
3393  * @codeCoverageIgnore
3394  */
3395 function wfGenerateToken( $salt = '' ) {
3396         $salt = serialize( $salt );
3397         return md5( mt_rand( 0, 0x7fffffff ) . $salt );
3398 }
3399
3400 /**
3401  * Replace all invalid characters with -
3402  *
3403  * @param $name Mixed: filename to process
3404  * @return String
3405  */
3406 function wfStripIllegalFilenameChars( $name ) {
3407         global $wgIllegalFileChars;
3408         $name = wfBaseName( $name );
3409         $name = preg_replace(
3410                 "/[^" . Title::legalChars() . "]" .
3411                         ( $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '' ) .
3412                         "/",
3413                 '-',
3414                 $name
3415         );
3416         return $name;
3417 }
3418
3419 /**
3420  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit;
3421  *
3422  * @return Integer value memory was set to.
3423  */
3424 function wfMemoryLimit() {
3425         global $wgMemoryLimit;
3426         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3427         if( $memlimit != -1 ) {
3428                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3429                 if( $conflimit == -1 ) {
3430                         wfDebug( "Removing PHP's memory limit\n" );
3431                         wfSuppressWarnings();
3432                         ini_set( 'memory_limit', $conflimit );
3433                         wfRestoreWarnings();
3434                         return $conflimit;
3435                 } elseif ( $conflimit > $memlimit ) {
3436                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3437                         wfSuppressWarnings();
3438                         ini_set( 'memory_limit', $conflimit );
3439                         wfRestoreWarnings();
3440                         return $conflimit;
3441                 }
3442         }
3443         return $memlimit;
3444 }
3445
3446 /**
3447  * Converts shorthand byte notation to integer form
3448  *
3449  * @param $string String
3450  * @return Integer
3451  */
3452 function wfShorthandToInteger( $string = '' ) {
3453         $string = trim( $string );
3454         if( $string === '' ) {
3455                 return -1;
3456         }
3457         $last = $string[strlen( $string ) - 1];
3458         $val = intval( $string );
3459         switch( $last ) {
3460                 case 'g':
3461                 case 'G':
3462                         $val *= 1024;
3463                         // break intentionally missing
3464                 case 'm':
3465                 case 'M':
3466                         $val *= 1024;
3467                         // break intentionally missing
3468                 case 'k':
3469                 case 'K':
3470                         $val *= 1024;
3471         }
3472
3473         return $val;
3474 }
3475
3476 /**
3477  * Get the normalised IETF language tag
3478  * See unit test for examples.
3479  *
3480  * @param $code String: The language code.
3481  * @return $langCode String: The language code which complying with BCP 47 standards.
3482  */
3483 function wfBCP47( $code ) {
3484         $codeSegment = explode( '-', $code );
3485         $codeBCP = array();
3486         foreach ( $codeSegment as $segNo => $seg ) {
3487                 if ( count( $codeSegment ) > 0 ) {
3488                         // when previous segment is x, it is a private segment and should be lc
3489                         if( $segNo > 0 && strtolower( $codeSegment[($segNo - 1)] ) == 'x') {
3490                                 $codeBCP[$segNo] = strtolower( $seg );
3491                         // ISO 3166 country code
3492                         } elseif ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3493                                 $codeBCP[$segNo] = strtoupper( $seg );
3494                         // ISO 15924 script code
3495                         } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3496                                 $codeBCP[$segNo] = ucfirst( strtolower( $seg ) );
3497                         // Use lowercase for other cases
3498                         } else {
3499                                 $codeBCP[$segNo] = strtolower( $seg );
3500                         }
3501                 } else {
3502                 // Use lowercase for single segment
3503                         $codeBCP[$segNo] = strtolower( $seg );
3504                 }
3505         }
3506         $langCode = implode( '-', $codeBCP );
3507         return $langCode;
3508 }
3509
3510 /**
3511  * Get a cache object.
3512  *
3513  * @param $inputType integer Cache type, one the the CACHE_* constants.
3514  * @return BagOStuff
3515  */
3516 function wfGetCache( $inputType ) {
3517         return ObjectCache::getInstance( $inputType );
3518 }
3519
3520 /**
3521  * Get the main cache object
3522  *
3523  * @return BagOStuff
3524  */
3525 function wfGetMainCache() {
3526         global $wgMainCacheType;
3527         return ObjectCache::getInstance( $wgMainCacheType );
3528 }
3529
3530 /**
3531  * Get the cache object used by the message cache
3532  *
3533  * @return BagOStuff
3534  */
3535 function wfGetMessageCacheStorage() {
3536         global $wgMessageCacheType;
3537         return ObjectCache::getInstance( $wgMessageCacheType );
3538 }
3539
3540 /**
3541  * Get the cache object used by the parser cache
3542  *
3543  * @return BagOStuff
3544  */
3545 function wfGetParserCacheStorage() {
3546         global $wgParserCacheType;
3547         return ObjectCache::getInstance( $wgParserCacheType );
3548 }
3549
3550 /**
3551  * Call hook functions defined in $wgHooks
3552  *
3553  * @param $event String: event name
3554  * @param $args Array: parameters passed to hook functions
3555  * @return Boolean
3556  */
3557 function wfRunHooks( $event, $args = array() ) {
3558         return Hooks::run( $event, $args );
3559 }