includes/GlobalFunctions.php

   1 <?php
   2 /**
   3  * Global functions used everywhere
   4  * @file
   5  */
   6
   7 if ( !defined( 'MEDIAWIKI' ) ) {
   8         die( "This file is part of MediaWiki, it is not a valid entry point" );
   9 }
  10
  11 // Hide compatibility functions from Doxygen
  12 /// @cond
  13
  14 /**
  15  * Compatibility functions
  16  *
  17  * We support PHP 5.2.3 and up.
  18  * Re-implementations of newer functions or functions in non-standard
  19  * PHP extensions may be included here.
  20  */
  21
  22 if( !function_exists( 'iconv' ) ) {
  23         /** @codeCoverageIgnore */
  24         function iconv( $from, $to, $string ) {
  25                 return Fallback::iconv( $from, $to, $string );
  26         }
  27 }
  28
  29 if ( !function_exists( 'mb_substr' ) ) {
  30         /** @codeCoverageIgnore */
  31         function mb_substr( $str, $start, $count='end' ) {
  32                 return Fallback::mb_substr( $str, $start, $count );
  33         }
  34
  35         /** @codeCoverageIgnore */
  36         function mb_substr_split_unicode( $str, $splitPos ) {
  37                 return Fallback::mb_substr_split_unicode( $str, $splitPos );
  38         }
  39 }
  40
  41 if ( !function_exists( 'mb_strlen' ) ) {
  42         /** @codeCoverageIgnore */
  43         function mb_strlen( $str, $enc = '' ) {
  44                 return Fallback::mb_strlen( $str, $enc );
  45         }
  46 }
  47
  48 if( !function_exists( 'mb_strpos' ) ) {
  49         /** @codeCoverageIgnore */
  50         function mb_strpos( $haystack, $needle, $offset = 0, $encoding = '' ) {
  51                 return Fallback::mb_strpos( $haystack, $needle, $offset, $encoding );
  52         }
  53
  54 }
  55
  56 if( !function_exists( 'mb_strrpos' ) ) {
  57         /** @codeCoverageIgnore */
  58         function mb_strrpos( $haystack, $needle, $offset = 0, $encoding = '' ) {
  59                 return Fallback::mb_strrpos( $haystack, $needle, $offset, $encoding );
  60         }
  61 }
  62
  63
  64 // Support for Wietse Venema's taint feature
  65 if ( !function_exists( 'istainted' ) ) {
  66         /** @codeCoverageIgnore */
  67         function istainted( $var ) {
  68                 return 0;
  69         }
  70         /** @codeCoverageIgnore */
  71         function taint( $var, $level = 0 ) {}
  72         /** @codeCoverageIgnore */
  73         function untaint( $var, $level = 0 ) {}
  74         define( 'TC_HTML', 1 );
  75         define( 'TC_SHELL', 1 );
  76         define( 'TC_MYSQL', 1 );
  77         define( 'TC_PCRE', 1 );
  78         define( 'TC_SELF', 1 );
  79 }
  80 /// @endcond
  81
  82 /**
  83  * Like array_diff( $a, $b ) except that it works with two-dimensional arrays.
  84  */
  85 function wfArrayDiff2( $a, $b ) {
  86         return array_udiff( $a, $b, 'wfArrayDiff2_cmp' );
  87 }
  88
  89 /**
  90  * @param $a
  91  * @param $b
  92  * @return int
  93  */
  94 function wfArrayDiff2_cmp( $a, $b ) {
  95         if ( !is_array( $a ) ) {
  96                 return strcmp( $a, $b );
  97         } elseif ( count( $a ) !== count( $b ) ) {
  98                 return count( $a ) < count( $b ) ? -1 : 1;
  99         } else {
 100                 reset( $a );
 101                 reset( $b );
 102                 while( ( list( , $valueA ) = each( $a ) ) && ( list( , $valueB ) = each( $b ) ) ) {
 103                         $cmp = strcmp( $valueA, $valueB );
 104                         if ( $cmp !== 0 ) {
 105                                 return $cmp;
 106                         }
 107                 }
 108                 return 0;
 109         }
 110 }
 111
 112 /**
 113  * Array lookup
 114  * Returns an array where the values in the first array are replaced by the
 115  * values in the second array with the corresponding keys
 116  *
 117  * @param $a Array
 118  * @param $b Array
 119  * @return array
 120  */
 121 function wfArrayLookup( $a, $b ) {
 122         return array_flip( array_intersect( array_flip( $a ), array_keys( $b ) ) );
 123 }
 124
 125 /**
 126  * Appends to second array if $value differs from that in $default
 127  *
 128  * @param $key String|Int
 129  * @param $value Mixed
 130  * @param $default Mixed
 131  * @param $changed Array to alter
 132  */
 133 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
 134         if ( is_null( $changed ) ) {
 135                 throw new MWException( 'GlobalFunctions::wfAppendToArrayIfNotDefault got null' );
 136         }
 137         if ( $default[$key] !== $value ) {
 138                 $changed[$key] = $value;
 139         }
 140 }
 141
 142 /**
 143  * Backwards array plus for people who haven't bothered to read the PHP manual
 144  * XXX: will not darn your socks for you.
 145  *
 146  * @param $array1 Array
 147  * @param [$array2, [...]] Arrays
 148  * @return Array
 149  */
 150 function wfArrayMerge( $array1/* ... */ ) {
 151         $args = func_get_args();
 152         $args = array_reverse( $args, true );
 153         $out = array();
 154         foreach ( $args as $arg ) {
 155                 $out += $arg;
 156         }
 157         return $out;
 158 }
 159
 160 /**
 161  * Merge arrays in the style of getUserPermissionsErrors, with duplicate removal
 162  * e.g.
 163  *      wfMergeErrorArrays(
 164  *              array( array( 'x' ) ),
 165  *              array( array( 'x', '2' ) ),
 166  *              array( array( 'x' ) ),
 167  *              array( array( 'y' ) )
 168  *      );
 169  * returns:
 170  *              array(
 171  *              array( 'x', '2' ),
 172  *              array( 'x' ),
 173  *              array( 'y' )
 174  *      )
 175  * @param varargs
 176  * @return Array
 177  */
 178 function wfMergeErrorArrays( /*...*/ ) {
 179         $args = func_get_args();
 180         $out = array();
 181         foreach ( $args as $errors ) {
 182                 foreach ( $errors as $params ) {
 183                         # @todo FIXME: Sometimes get nested arrays for $params,
 184                         # which leads to E_NOTICEs
 185                         $spec = implode( "\t", $params );
 186                         $out[$spec] = $params;
 187                 }
 188         }
 189         return array_values( $out );
 190 }
 191
 192 /**
 193  * Insert array into another array after the specified *KEY*
 194  *
 195  * @param $array Array: The array.
 196  * @param $insert Array: The array to insert.
 197  * @param $after Mixed: The key to insert after
 198  * @return Array
 199  */
 200 function wfArrayInsertAfter( $array, $insert, $after ) {
 201         // Find the offset of the element to insert after.
 202         $keys = array_keys( $array );
 203         $offsetByKey = array_flip( $keys );
 204
 205         $offset = $offsetByKey[$after];
 206
 207         // Insert at the specified offset
 208         $before = array_slice( $array, 0, $offset + 1, true );
 209         $after = array_slice( $array, $offset + 1, count( $array ) - $offset, true );
 210
 211         $output = $before + $insert + $after;
 212
 213         return $output;
 214 }
 215
 216 /**
 217  * Recursively converts the parameter (an object) to an array with the same data
 218  *
 219  * @param $objOrArray Object|Array
 220  * @param $recursive Bool
 221  * @return Array
 222  */
 223 function wfObjectToArray( $objOrArray, $recursive = true ) {
 224         $array = array();
 225         if( is_object( $objOrArray ) ) {
 226                 $objOrArray = get_object_vars( $objOrArray );
 227         }
 228         foreach ( $objOrArray as $key => $value ) {
 229                 if ( $recursive && ( is_object( $value ) || is_array( $value ) ) ) {
 230                         $value = wfObjectToArray( $value );
 231                 }
 232
 233                 $array[$key] = $value;
 234         }
 235
 236         return $array;
 237 }
 238
 239 /**
 240  * Wrapper around array_map() which also taints variables
 241  *
 242  * @param  $function Callback
 243  * @param  $input Array
 244  * @return Array
 245  */
 246 function wfArrayMap( $function, $input ) {
 247         $ret = array_map( $function, $input );
 248         foreach ( $ret as $key => $value ) {
 249                 $taint = istainted( $input[$key] );
 250                 if ( $taint ) {
 251                         taint( $ret[$key], $taint );
 252                 }
 253         }
 254         return $ret;
 255 }
 256
 257 /**
 258  * Get a random decimal value between 0 and 1, in a way
 259  * not likely to give duplicate values for any realistic
 260  * number of articles.
 261  *
 262  * @return string
 263  */
 264 function wfRandom() {
 265         # The maximum random value is "only" 2^31-1, so get two random
 266         # values to reduce the chance of dupes
 267         $max = mt_getrandmax() + 1;
 268         $rand = number_format( ( mt_rand() * $max + mt_rand() )
 269                 / $max / $max, 12, '.', '' );
 270         return $rand;
 271 }
 272
 273 /**
 274  * We want some things to be included as literal characters in our title URLs
 275  * for prettiness, which urlencode encodes by default.  According to RFC 1738,
 276  * all of the following should be safe:
 277  *
 278  * ;:@&=$-_.+!*'(),
 279  *
 280  * But + is not safe because it's used to indicate a space; &= are only safe in
 281  * paths and not in queries (and we don't distinguish here); ' seems kind of
 282  * scary; and urlencode() doesn't touch -_. to begin with.  Plus, although /
 283  * is reserved, we don't care.  So the list we unescape is:
 284  *
 285  * ;:@$!*(),/
 286  *
 287  * However, IIS7 redirects fail when the url contains a colon (Bug 22709),
 288  * so no fancy : for IIS7.
 289  *
 290  * %2F in the page titles seems to fatally break for some reason.
 291  *
 292  * @param $s String:
 293  * @return string
 294 */
 295 function wfUrlencode( $s ) {
 296         static $needle;
 297         if ( is_null( $s ) ) {
 298                 $needle = null;
 299                 return '';
 300         }
 301
 302         if ( is_null( $needle ) ) {
 303                 $needle = array( '%3B', '%40', '%24', '%21', '%2A', '%28', '%29', '%2C', '%2F' );
 304                 if ( !isset( $_SERVER['SERVER_SOFTWARE'] ) || ( strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/7' ) === false ) ) {
 305                         $needle[] = '%3A';
 306                 }
 307         }
 308
 309         $s = urlencode( $s );
 310         $s = str_ireplace(
 311                 $needle,
 312                 array( ';', '@', '$', '!', '*', '(', ')', ',', '/', ':' ),
 313                 $s
 314         );
 315
 316         return $s;
 317 }
 318
 319 /**
 320  * This function takes two arrays as input, and returns a CGI-style string, e.g.
 321  * "days=7&limit=100". Options in the first array override options in the second.
 322  * Options set to "" will not be output.
 323  *
 324  * @param $array1 Array ( String|Array )
 325  * @param $array2 Array ( String|Array )
 326  * @param $prefix String
 327  * @return String
 328  */
 329 function wfArrayToCGI( $array1, $array2 = null, $prefix = '' ) {
 330         if ( !is_null( $array2 ) ) {
 331                 $array1 = $array1 + $array2;
 332         }
 333
 334         $cgi = '';
 335         foreach ( $array1 as $key => $value ) {
 336                 if ( $value !== '' ) {
 337                         if ( $cgi != '' ) {
 338                                 $cgi .= '&';
 339                         }
 340                         if ( $prefix !== '' ) {
 341                                 $key = $prefix . "[$key]";
 342                         }
 343                         if ( is_array( $value ) ) {
 344                                 $firstTime = true;
 345                                 foreach ( $value as $k => $v ) {
 346                                         $cgi .= $firstTime ? '' : '&';
 347                                         if ( is_array( $v ) ) {
 348                                                 $cgi .= wfArrayToCGI( $v, null, $key . "[$k]" );
 349                                         } else {
 350                                                 $cgi .= urlencode( $key . "[$k]" ) . '=' . urlencode( $v );
 351                                         }
 352                                         $firstTime = false;
 353                                 }
 354                         } else {
 355                                 if ( is_object( $value ) ) {
 356                                         $value = $value->__toString();
 357                                 }
 358                                 $cgi .= urlencode( $key ) . '=' . urlencode( $value );
 359                         }
 360                 }
 361         }
 362         return $cgi;
 363 }
 364
 365 /**
 366  * This is the logical opposite of wfArrayToCGI(): it accepts a query string as
 367  * its argument and returns the same string in array form.  This allows compa-
 368  * tibility with legacy functions that accept raw query strings instead of nice
 369  * arrays.  Of course, keys and values are urldecode()d.  Don't try passing in-
 370  * valid query strings, or it will explode.
 371  *
 372  * @param $query String: query string
 373  * @return array Array version of input
 374  */
 375 function wfCgiToArray( $query ) {
 376         if ( isset( $query[0] ) && $query[0] == '?' ) {
 377                 $query = substr( $query, 1 );
 378         }
 379         $bits = explode( '&', $query );
 380         $ret = array();
 381         foreach ( $bits as $bit ) {
 382                 if ( $bit === '' ) {
 383                         continue;
 384                 }
 385                 list( $key, $value ) = explode( '=', $bit );
 386                 $key = urldecode( $key );
 387                 $value = urldecode( $value );
 388                 if ( strpos( $key, '[' ) !== false ) {
 389                         $keys = array_reverse( explode( '[', $key ) );
 390                         $key = array_pop( $keys );
 391                         $temp = $value;
 392                         foreach ( $keys as $k ) {
 393                                 $k = substr( $k, 0, -1 );
 394                                 $temp = array( $k => $temp );
 395                         }
 396                         if ( isset( $ret[$key] ) ) {
 397                                 $ret[$key] = array_merge( $ret[$key], $temp );
 398                         } else {
 399                                 $ret[$key] = $temp;
 400                         }
 401                 } else {
 402                         $ret[$key] = $value;
 403                 }
 404         }
 405         return $ret;
 406 }
 407
 408 /**
 409  * Append a query string to an existing URL, which may or may not already
 410  * have query string parameters already. If so, they will be combined.
 411  *
 412  * @param $url String
 413  * @param $query Mixed: string or associative array
 414  * @return string
 415  */
 416 function wfAppendQuery( $url, $query ) {
 417         if ( is_array( $query ) ) {
 418                 $query = wfArrayToCGI( $query );
 419         }
 420         if( $query != '' ) {
 421                 if( false === strpos( $url, '?' ) ) {
 422                         $url .= '?';
 423                 } else {
 424                         $url .= '&';
 425                 }
 426                 $url .= $query;
 427         }
 428         return $url;
 429 }
 430
 431 /**
 432  * Expand a potentially local URL to a fully-qualified URL.  Assumes $wgServer
 433  * is correct.
 434  *
 435  * The meaning of the PROTO_* constants is as follows:
 436  * PROTO_HTTP: Output a URL starting with http://
 437  * PROTO_HTTPS: Output a URL starting with https://
 438  * PROTO_RELATIVE: Output a URL starting with // (protocol-relative URL)
 439  * PROTO_CURRENT: Output a URL starting with either http:// or https:// , depending on which protocol was used for the current incoming request
 440  * PROTO_CANONICAL: For URLs without a domain, like /w/index.php , use $wgCanonicalServer. For protocol-relative URLs, use the protocol of $wgCanonicalServer
 441  * PROTO_INTERNAL: Like PROTO_CANONICAL, but uses $wgInternalServer instead of $wgCanonicalServer
 442  *
 443  * @todo this won't work with current-path-relative URLs
 444  * like "subdir/foo.html", etc.
 445  *
 446  * @param $url String: either fully-qualified or a local path + query
 447  * @param $defaultProto Mixed: one of the PROTO_* constants. Determines the protocol to use if $url or $wgServer is protocol-relative
 448  * @return string Fully-qualified URL
 449  */
 450 function wfExpandUrl( $url, $defaultProto = PROTO_CURRENT ) {
 451         global $wgServer, $wgCanonicalServer, $wgInternalServer;
 452         $serverUrl = $wgServer;
 453         if ( $defaultProto === PROTO_CANONICAL ) {
 454                 $serverUrl = $wgCanonicalServer;
 455         }
 456         // Make $wgInternalServer fall back to $wgServer if not set
 457         if ( $defaultProto === PROTO_INTERNAL && $wgInternalServer !== false ) {
 458                 $serverUrl = $wgInternalServer;
 459         }
 460         if ( $defaultProto === PROTO_CURRENT ) {
 461                 $defaultProto = WebRequest::detectProtocol() . '://';
 462         }
 463
 464         // Analyze $serverUrl to obtain its protocol
 465         $bits = wfParseUrl( $serverUrl );
 466         $serverHasProto = $bits && $bits['scheme'] != '';
 467
 468         if ( $defaultProto === PROTO_CANONICAL || $defaultProto === PROTO_INTERNAL ) {
 469                 if ( $serverHasProto ) {
 470                         $defaultProto = $bits['scheme'] . '://';
 471                 } else {
 472                         // $wgCanonicalServer or $wgInternalServer doesn't have a protocol. This really isn't supposed to happen
 473                         // Fall back to HTTP in this ridiculous case
 474                         $defaultProto = PROTO_HTTP;
 475                 }
 476         }
 477
 478         $defaultProtoWithoutSlashes = substr( $defaultProto, 0, -2 );
 479
 480         if ( substr( $url, 0, 2 ) == '//' ) {
 481                 return $defaultProtoWithoutSlashes . $url;
 482         } elseif ( substr( $url, 0, 1 ) == '/' ) {
 483                 // If $serverUrl is protocol-relative, prepend $defaultProtoWithoutSlashes, otherwise leave it alone
 484                 return ( $serverHasProto ? '' : $defaultProtoWithoutSlashes ) . $serverUrl . $url;
 485         } else {
 486                 return $url;
 487         }
 488 }
 489
 490 /**
 491  * Remove all dot-segments in the provided URL path.  For example,
 492  * '/a/./b/../c/' becomes '/a/c/'.  For details on the algorithm, please see
 493  * RFC3986 section 5.2.4.
 494  *
 495  * @todo Need to integrate this into wfExpandUrl (bug 32168)
 496  *
 497  * @param $urlPath String URL path, potentially containing dot-segments
 498  * @return string URL path with all dot-segments removed
 499  */
 500 function wfRemoveDotSegments( $urlPath ) {
 501         $output = '';
 502
 503         while ( $urlPath ) {
 504                 $matches = null;
 505                 if ( preg_match('%^\.\.?/%', $urlPath, $matches) ) {
 506                         # Step A, remove leading "../" or "./"
 507                         $urlPath = substr( $urlPath, strlen( $matches[0] ) );
 508                 } elseif ( preg_match( '%^/\.(/|$)%', $urlPath, $matches ) ) {
 509                         # Step B, replace leading "/.$" or "/./" with "/"
 510                         $start = strlen( $matches[0] );
 511                         $urlPath = '/' . substr( $urlPath, $start );
 512                 } elseif ( preg_match( '%^/\.\.(/|$)%', $urlPath, $matches ) ) {
 513                         # Step C, replace leading "/..$" or "/../" with "/" and
 514                         # remove last path component in output
 515                         $start = strlen( $matches[0] );
 516                         $urlPath = '/' . substr( $urlPath, $start );
 517                         $output = preg_replace('%(^|/)[^/]*$%', '', $output);
 518                 } elseif ( preg_match( '%^\.\.?$%', $urlPath, $matches ) ) {
 519                         # Step D, remove "^..$" or "^.$"
 520                         $urlPath = '';
 521                 } else {
 522                         # Step E, move leading path segment to output
 523                         preg_match( '%^/?[^/]*%', $urlPath, $matches );
 524                         $urlPath = substr( $urlPath, strlen( $matches[0] ) );
 525                         $output .= $matches[0];
 526                 }
 527         }
 528
 529         return $output;
 530 }
 531
 532 /**
 533  * Returns a regular expression of url protocols
 534  *
 535  * @param $includeProtocolRelative bool If false, remove '//' from the returned protocol list.
 536  *        DO NOT USE this directly, use wfUrlProtocolsWithoutProtRel() instead
 537  * @return String
 538  */
 539 function wfUrlProtocols( $includeProtocolRelative = true ) {
 540         global $wgUrlProtocols;
 541
 542         // Cache return values separately based on $includeProtocolRelative
 543         static $withProtRel = null, $withoutProtRel = null;
 544         $cachedValue = $includeProtocolRelative ? $withProtRel : $withoutProtRel;
 545         if ( !is_null( $cachedValue ) ) {
 546                 return $cachedValue;
 547         }
 548
 549         // Support old-style $wgUrlProtocols strings, for backwards compatibility
 550         // with LocalSettings files from 1.5
 551         if ( is_array( $wgUrlProtocols ) ) {
 552                 $protocols = array();
 553                 foreach ( $wgUrlProtocols as $protocol ) {
 554                         // Filter out '//' if !$includeProtocolRelative
 555                         if ( $includeProtocolRelative || $protocol !== '//' ) {
 556                                 $protocols[] = preg_quote( $protocol, '/' );
 557                         }
 558                 }
 559
 560                 $retval = implode( '|', $protocols );
 561         } else {
 562                 // Ignore $includeProtocolRelative in this case
 563                 // This case exists for pre-1.6 compatibility, and we can safely assume
 564                 // that '//' won't appear in a pre-1.6 config because protocol-relative
 565                 // URLs weren't supported until 1.18
 566                 $retval = $wgUrlProtocols;
 567         }
 568
 569         // Cache return value
 570         if ( $includeProtocolRelative ) {
 571                 $withProtRel = $retval;
 572         } else {
 573                 $withoutProtRel = $retval;
 574         }
 575         return $retval;
 576 }
 577
 578 /**
 579  * Like wfUrlProtocols(), but excludes '//' from the protocol list. Use this if
 580  * you need a regex that matches all URL protocols but does not match protocol-
 581  * relative URLs
 582  * @return String
 583  */
 584 function wfUrlProtocolsWithoutProtRel() {
 585         return wfUrlProtocols( false );
 586 }
 587
 588 /**
 589  * parse_url() work-alike, but non-broken.  Differences:
 590  *
 591  * 1) Does not raise warnings on bad URLs (just returns false)
 592  * 2) Handles protocols that don't use :// (e.g., mailto: and news: , as well as protocol-relative URLs) correctly
 593  * 3) Adds a "delimiter" element to the array, either '://', ':' or '//' (see (2))
 594  *
 595  * @param $url String: a URL to parse
 596  * @return Array: bits of the URL in an associative array, per PHP docs
 597  */
 598 function wfParseUrl( $url ) {
 599         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
 600
 601         // Protocol-relative URLs are handled really badly by parse_url(). It's so bad that the easiest
 602         // way to handle them is to just prepend 'http:' and strip the protocol out later
 603         $wasRelative = substr( $url, 0, 2 ) == '//';
 604         if ( $wasRelative ) {
 605                 $url = "http:$url";
 606         }
 607         wfSuppressWarnings();
 608         $bits = parse_url( $url );
 609         wfRestoreWarnings();
 610         // parse_url() returns an array without scheme for some invalid URLs, e.g.
 611         // parse_url("%0Ahttp://example.com") == array( 'host' => '%0Ahttp', 'path' => 'example.com' )
 612         if ( !$bits || !isset( $bits['scheme'] ) ) {
 613                 return false;
 614         }
 615
 616         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
 617         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
 618                 $bits['delimiter'] = '://';
 619         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
 620                 $bits['delimiter'] = ':';
 621                 // parse_url detects for news: and mailto: the host part of an url as path
 622                 // We have to correct this wrong detection
 623                 if ( isset( $bits['path'] ) ) {
 624                         $bits['host'] = $bits['path'];
 625                         $bits['path'] = '';
 626                 }
 627         } else {
 628                 return false;
 629         }
 630
 631         /* Provide an empty host for eg. file:/// urls (see bug 28627) */
 632         if ( !isset( $bits['host'] ) ) {
 633                 $bits['host'] = '';
 634
 635                 /* parse_url loses the third / for file:///c:/ urls (but not on variants) */
 636                 if ( substr( $bits['path'], 0, 1 ) !== '/' ) {
 637                         $bits['path'] = '/' . $bits['path'];
 638                 }
 639         }
 640
 641         // If the URL was protocol-relative, fix scheme and delimiter
 642         if ( $wasRelative ) {
 643                 $bits['scheme'] = '';
 644                 $bits['delimiter'] = '//';
 645         }
 646         return $bits;
 647 }
 648
 649 /**
 650  * Make a URL index, appropriate for the el_index field of externallinks.
 651  *
 652  * @param $url String
 653  * @return String
 654  */
 655 function wfMakeUrlIndex( $url ) {
 656         $bits = wfParseUrl( $url );
 657
 658         // Reverse the labels in the hostname, convert to lower case
 659         // For emails reverse domainpart only
 660         if ( $bits['scheme'] == 'mailto' ) {
 661                 $mailparts = explode( '@', $bits['host'], 2 );
 662                 if ( count( $mailparts ) === 2 ) {
 663                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
 664                 } else {
 665                         // No domain specified, don't mangle it
 666                         $domainpart = '';
 667                 }
 668                 $reversedHost = $domainpart . '@' . $mailparts[0];
 669         } else {
 670                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
 671         }
 672         // Add an extra dot to the end
 673         // Why? Is it in wrong place in mailto links?
 674         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
 675                 $reversedHost .= '.';
 676         }
 677         // Reconstruct the pseudo-URL
 678         $prot = $bits['scheme'];
 679         $index = $prot . $bits['delimiter'] . $reversedHost;
 680         // Leave out user and password. Add the port, path, query and fragment
 681         if ( isset( $bits['port'] ) ) {
 682                 $index .= ':' . $bits['port'];
 683         }
 684         if ( isset( $bits['path'] ) ) {
 685                 $index .= $bits['path'];
 686         } else {
 687                 $index .= '/';
 688         }
 689         if ( isset( $bits['query'] ) ) {
 690                 $index .= '?' . $bits['query'];
 691         }
 692         if ( isset( $bits['fragment'] ) ) {
 693                 $index .= '#' . $bits['fragment'];
 694         }
 695         return $index;
 696 }
 697
 698 /**
 699  * Check whether a given URL has a domain that occurs in a given set of domains
 700  * @param $url string URL
 701  * @param $domains array Array of domains (strings)
 702  * @return bool True if the host part of $url ends in one of the strings in $domains
 703  */
 704 function wfMatchesDomainList( $url, $domains ) {
 705         $bits = wfParseUrl( $url );
 706         if ( is_array( $bits ) && isset( $bits['host'] ) ) {
 707                 foreach ( (array)$domains as $domain ) {
 708                         // FIXME: This gives false positives. http://nds-nl.wikipedia.org will match nl.wikipedia.org
 709                         // We should use something that interprets dots instead
 710                         if ( substr( $bits['host'], -strlen( $domain ) ) === $domain ) {
 711                                 return true;
 712                         }
 713                 }
 714         }
 715         return false;
 716 }
 717
 718 /**
 719  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
 720  * In normal operation this is a NOP.
 721  *
 722  * Controlling globals:
 723  * $wgDebugLogFile - points to the log file
 724  * $wgProfileOnly - if set, normal debug messages will not be recorded.
 725  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
 726  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
 727  *
 728  * @param $text String
 729  * @param $logonly Bool: set true to avoid appearing in HTML when $wgDebugComments is set
 730  */
 731 function wfDebug( $text, $logonly = false ) {
 732         global $wgOut, $wgDebugLogFile, $wgDebugComments, $wgProfileOnly, $wgDebugRawPage;
 733         global $wgDebugLogPrefix, $wgShowDebug;
 734
 735         static $cache = array(); // Cache of unoutputted messages
 736         $text = wfDebugTimer() . $text;
 737
 738         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
 739                 return;
 740         }
 741
 742         if ( ( $wgDebugComments || $wgShowDebug ) && !$logonly ) {
 743                 $cache[] = $text;
 744
 745                 if ( isset( $wgOut ) && is_object( $wgOut ) ) {
 746                         // add the message and any cached messages to the output
 747                         array_map( array( $wgOut, 'debug' ), $cache );
 748                         $cache = array();
 749                 }
 750         }
 751         if ( wfRunHooks( 'Debug', array( $text, null /* no log group */ ) ) ) {
 752                 if ( $wgDebugLogFile != '' && !$wgProfileOnly ) {
 753                         # Strip unprintables; they can switch terminal modes when binary data
 754                         # gets dumped, which is pretty annoying.
 755                         $text = preg_replace( '![\x00-\x08\x0b\x0c\x0e-\x1a\x1c-\x1f]!', ' ', $text );
 756                         $text = $wgDebugLogPrefix . $text;
 757                         wfErrorLog( $text, $wgDebugLogFile );
 758                 }
 759         }
 760 }
 761
 762 /**
 763  * Returns true if debug logging should be suppressed if $wgDebugRawPage = false
 764  */
 765 function wfIsDebugRawPage() {
 766         static $cache;
 767         if ( $cache !== null ) {
 768                 return $cache;
 769         }
 770         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
 771         if ( ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' )
 772                 || (
 773                         isset( $_SERVER['SCRIPT_NAME'] )
 774                         && substr( $_SERVER['SCRIPT_NAME'], -8 ) == 'load.php'
 775                 ) )
 776         {
 777                 $cache = true;
 778         } else {
 779                 $cache = false;
 780         }
 781         return $cache;
 782 }
 783
 784 /**
 785  * Get microsecond timestamps for debug logs
 786  *
 787  * @return string
 788  */
 789 function wfDebugTimer() {
 790         global $wgDebugTimestamps;
 791         if ( !$wgDebugTimestamps ) {
 792                 return '';
 793         }
 794         static $start = null;
 795
 796         if ( $start === null ) {
 797                 $start = microtime( true );
 798                 $prefix = "\n$start";
 799         } else {
 800                 $prefix = sprintf( "%6.4f", microtime( true ) - $start );
 801         }
 802         $mem = sprintf( "%5.1fM", ( memory_get_usage( true ) / (1024*1024) ) );
 803         return "$prefix $mem  " ;
 804 }
 805
 806 /**
 807  * Send a line giving PHP memory usage.
 808  *
 809  * @param $exact Bool: print exact values instead of kilobytes (default: false)
 810  */
 811 function wfDebugMem( $exact = false ) {
 812         $mem = memory_get_usage();
 813         if( !$exact ) {
 814                 $mem = floor( $mem / 1024 ) . ' kilobytes';
 815         } else {
 816                 $mem .= ' bytes';
 817         }
 818         wfDebug( "Memory usage: $mem\n" );
 819 }
 820
 821 /**
 822  * Send a line to a supplementary debug log file, if configured, or main debug log if not.
 823  * $wgDebugLogGroups[$logGroup] should be set to a filename to send to a separate log.
 824  *
 825  * @param $logGroup String
 826  * @param $text String
 827  * @param $public Bool: whether to log the event in the public log if no private
 828  *                     log file is specified, (default true)
 829  */
 830 function wfDebugLog( $logGroup, $text, $public = true ) {
 831         global $wgDebugLogGroups, $wgShowHostnames;
 832         $text = trim( $text ) . "\n";
 833         if( isset( $wgDebugLogGroups[$logGroup] ) ) {
 834                 $time = wfTimestamp( TS_DB );
 835                 $wiki = wfWikiID();
 836                 if ( $wgShowHostnames ) {
 837                         $host = wfHostname();
 838                 } else {
 839                         $host = '';
 840                 }
 841                 if ( wfRunHooks( 'Debug', array( $text, $logGroup ) ) ) {
 842                         wfErrorLog( "$time $host $wiki: $text", $wgDebugLogGroups[$logGroup] );
 843                 }
 844         } elseif ( $public === true ) {
 845                 wfDebug( $text, true );
 846         }
 847 }
 848
 849 /**
 850  * Log for database errors
 851  *
 852  * @param $text String: database error message.
 853  */
 854 function wfLogDBError( $text ) {
 855         global $wgDBerrorLog, $wgDBname;
 856         if ( $wgDBerrorLog ) {
 857                 $host = trim(`hostname`);
 858                 $text = date( 'D M j G:i:s T Y' ) . "\t$host\t$wgDBname\t$text";
 859                 wfErrorLog( $text, $wgDBerrorLog );
 860         }
 861 }
 862
 863 /**
 864  * Log to a file without getting "file size exceeded" signals.
 865  *
 866  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
 867  * send lines to the specified port, prefixed by the specified prefix and a space.
 868  *
 869  * @param $text String
 870  * @param $file String filename
 871  */
 872 function wfErrorLog( $text, $file ) {
 873         if ( substr( $file, 0, 4 ) == 'udp:' ) {
 874                 # Needs the sockets extension
 875                 if ( preg_match( '!^(tcp|udp):(?://)?\[([0-9a-fA-F:]+)\]:(\d+)(?:/(.*))?$!', $file, $m ) ) {
 876                         // IPv6 bracketed host
 877                         $host = $m[2];
 878                         $port = intval( $m[3] );
 879                         $prefix = isset( $m[4] ) ? $m[4] : false;
 880                         $domain = AF_INET6;
 881                 } elseif ( preg_match( '!^(tcp|udp):(?://)?([a-zA-Z0-9.-]+):(\d+)(?:/(.*))?$!', $file, $m ) ) {
 882                         $host = $m[2];
 883                         if ( !IP::isIPv4( $host ) ) {
 884                                 $host = gethostbyname( $host );
 885                         }
 886                         $port = intval( $m[3] );
 887                         $prefix = isset( $m[4] ) ? $m[4] : false;
 888                         $domain = AF_INET;
 889                 } else {
 890                         throw new MWException( __METHOD__ . ': Invalid UDP specification' );
 891                 }
 892
 893                 // Clean it up for the multiplexer
 894                 if ( strval( $prefix ) !== '' ) {
 895                         $text = preg_replace( '/^/m', $prefix . ' ', $text );
 896
 897                         // Limit to 64KB
 898                         if ( strlen( $text ) > 65506 ) {
 899                                 $text = substr( $text, 0, 65506 );
 900                         }
 901
 902                         if ( substr( $text, -1 ) != "\n" ) {
 903                                 $text .= "\n";
 904                         }
 905                 } elseif ( strlen( $text ) > 65507 ) {
 906                         $text = substr( $text, 0, 65507 );
 907                 }
 908
 909                 $sock = socket_create( $domain, SOCK_DGRAM, SOL_UDP );
 910                 if ( !$sock ) {
 911                         return;
 912                 }
 913
 914                 socket_sendto( $sock, $text, strlen( $text ), 0, $host, $port );
 915                 socket_close( $sock );
 916         } else {
 917                 wfSuppressWarnings();
 918                 $exists = file_exists( $file );
 919                 $size = $exists ? filesize( $file ) : false;
 920                 if ( !$exists || ( $size !== false && $size + strlen( $text ) < 0x7fffffff ) ) {
 921                         file_put_contents( $file, $text, FILE_APPEND );
 922                 }
 923                 wfRestoreWarnings();
 924         }
 925 }
 926
 927 /**
 928  * @todo document
 929  */
 930 function wfLogProfilingData() {
 931         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
 932         global $wgProfileLimit, $wgUser;
 933
 934         $profiler = Profiler::instance();
 935
 936         # Profiling must actually be enabled...
 937         if ( $profiler->isStub() ) {
 938                 return;
 939         }
 940
 941         // Get total page request time and only show pages that longer than
 942         // $wgProfileLimit time (default is 0)
 943         $now = wfTime();
 944         $elapsed = $now - $wgRequestTime;
 945         if ( $elapsed <= $wgProfileLimit ) {
 946                 return;
 947         }
 948
 949         $profiler->logData();
 950
 951         // Check whether this should be logged in the debug file.
 952         if ( $wgDebugLogFile == '' || ( !$wgDebugRawPage && wfIsDebugRawPage() ) ) {
 953                 return;
 954         }
 955
 956         $forward = '';
 957         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
 958                 $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
 959         }
 960         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
 961                 $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
 962         }
 963         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
 964                 $forward .= ' from ' . $_SERVER['HTTP_FROM'];
 965         }
 966         if ( $forward ) {
 967                 $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
 968         }
 969         // Don't load $wgUser at this late stage just for statistics purposes
 970         // @todo FIXME: We can detect some anons even if it is not loaded. See User::getId()
 971         if ( $wgUser->isItemLoaded( 'id' ) && $wgUser->isAnon() ) {
 972                 $forward .= ' anon';
 973         }
 974         $log = sprintf( "%s\t%04.3f\t%s\n",
 975                 gmdate( 'YmdHis' ), $elapsed,
 976                 urldecode( $wgRequest->getRequestURL() . $forward ) );
 977
 978         wfErrorLog( $log . $profiler->getOutput(), $wgDebugLogFile );
 979 }
 980
 981 /**
 982  * Check if the wiki read-only lock file is present. This can be used to lock
 983  * off editing functions, but doesn't guarantee that the database will not be
 984  * modified.
 985  *
 986  * @return bool
 987  */
 988 function wfReadOnly() {
 989         global $wgReadOnlyFile, $wgReadOnly;
 990
 991         if ( !is_null( $wgReadOnly ) ) {
 992                 return (bool)$wgReadOnly;
 993         }
 994         if ( $wgReadOnlyFile == '' ) {
 995                 return false;
 996         }
 997         // Set $wgReadOnly for faster access next time
 998         if ( is_file( $wgReadOnlyFile ) ) {
 999                 $wgReadOnly = file_get_contents( $wgReadOnlyFile );
1000         } else {
1001                 $wgReadOnly = false;
1002         }
1003         return (bool)$wgReadOnly;
1004 }
1005
1006 /**
1007  * @return bool
1008  */
1009 function wfReadOnlyReason() {
1010         global $wgReadOnly;
1011         wfReadOnly();
1012         return $wgReadOnly;
1013 }
1014
1015 /**
1016  * Return a Language object from $langcode
1017  *
1018  * @param $langcode Mixed: either:
1019  *                  - a Language object
1020  *                  - code of the language to get the message for, if it is
1021  *                    a valid code create a language for that language, if
1022  *                    it is a string but not a valid code then make a basic
1023  *                    language object
1024  *                  - a boolean: if it's false then use the global object for
1025  *                    the current user's language (as a fallback for the old parameter
1026  *                    functionality), or if it is true then use global object
1027  *                    for the wiki's content language.
1028  * @return Language object
1029  */
1030 function wfGetLangObj( $langcode = false ) {
1031         # Identify which language to get or create a language object for.
1032         # Using is_object here due to Stub objects.
1033         if( is_object( $langcode ) ) {
1034                 # Great, we already have the object (hopefully)!
1035                 return $langcode;
1036         }
1037
1038         global $wgContLang, $wgLanguageCode;
1039         if( $langcode === true || $langcode === $wgLanguageCode ) {
1040                 # $langcode is the language code of the wikis content language object.
1041                 # or it is a boolean and value is true
1042                 return $wgContLang;
1043         }
1044
1045         global $wgLang;
1046         if( $langcode === false || $langcode === $wgLang->getCode() ) {
1047                 # $langcode is the language code of user language object.
1048                 # or it was a boolean and value is false
1049                 return $wgLang;
1050         }
1051
1052         $validCodes = array_keys( Language::getLanguageNames() );
1053         if( in_array( $langcode, $validCodes ) ) {
1054                 # $langcode corresponds to a valid language.
1055                 return Language::factory( $langcode );
1056         }
1057
1058         # $langcode is a string, but not a valid language code; use content language.
1059         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
1060         return $wgContLang;
1061 }
1062
1063 /**
1064  * Old function when $wgBetterDirectionality existed
1065  * Removed in core, kept in extensions for backwards compat.
1066  *
1067  * @deprecated since 1.18
1068  * @return Language
1069  */
1070 function wfUILang() {
1071         global $wgLang;
1072         return $wgLang;
1073 }
1074
1075 /**
1076  * This is the new function for getting translated interface messages.
1077  * See the Message class for documentation how to use them.
1078  * The intention is that this function replaces all old wfMsg* functions.
1079  * @param $key \string Message key.
1080  * Varargs: normal message parameters.
1081  * @return Message
1082  * @since 1.17
1083  */
1084 function wfMessage( $key /*...*/) {
1085         $params = func_get_args();
1086         array_shift( $params );
1087         if ( isset( $params[0] ) && is_array( $params[0] ) ) {
1088                 $params = $params[0];
1089         }
1090         return new Message( $key, $params );
1091 }
1092
1093 /**
1094  * This function accepts multiple message keys and returns a message instance
1095  * for the first message which is non-empty. If all messages are empty then an
1096  * instance of the first message key is returned.
1097  * @param varargs: message keys
1098  * @return Message
1099  * @since 1.18
1100  */
1101 function wfMessageFallback( /*...*/ ) {
1102         $args = func_get_args();
1103         return MWFunction::callArray( 'Message::newFallbackSequence', $args );
1104 }
1105
1106 /**
1107  * Get a message from anywhere, for the current user language.
1108  *
1109  * Use wfMsgForContent() instead if the message should NOT
1110  * change depending on the user preferences.
1111  *
1112  * @param $key String: lookup key for the message, usually
1113  *    defined in languages/Language.php
1114  *
1115  * Parameters to the message, which can be used to insert variable text into
1116  * it, can be passed to this function in the following formats:
1117  * - One per argument, starting at the second parameter
1118  * - As an array in the second parameter
1119  * These are not shown in the function definition.
1120  *
1121  * @return String
1122  */
1123 function wfMsg( $key ) {
1124         $args = func_get_args();
1125         array_shift( $args );
1126         return wfMsgReal( $key, $args );
1127 }
1128
1129 /**
1130  * Same as above except doesn't transform the message
1131  *
1132  * @param $key String
1133  * @return String
1134  */
1135 function wfMsgNoTrans( $key ) {
1136         $args = func_get_args();
1137         array_shift( $args );
1138         return wfMsgReal( $key, $args, true, false, false );
1139 }
1140
1141 /**
1142  * Get a message from anywhere, for the current global language
1143  * set with $wgLanguageCode.
1144  *
1145  * Use this if the message should NOT change dependent on the
1146  * language set in the user's preferences. This is the case for
1147  * most text written into logs, as well as link targets (such as
1148  * the name of the copyright policy page). Link titles, on the
1149  * other hand, should be shown in the UI language.
1150  *
1151  * Note that MediaWiki allows users to change the user interface
1152  * language in their preferences, but a single installation
1153  * typically only contains content in one language.
1154  *
1155  * Be wary of this distinction: If you use wfMsg() where you should
1156  * use wfMsgForContent(), a user of the software may have to
1157  * customize potentially hundreds of messages in
1158  * order to, e.g., fix a link in every possible language.
1159  *
1160  * @param $key String: lookup key for the message, usually
1161  *     defined in languages/Language.php
1162  * @return String
1163  */
1164 function wfMsgForContent( $key ) {
1165         global $wgForceUIMsgAsContentMsg;
1166         $args = func_get_args();
1167         array_shift( $args );
1168         $forcontent = true;
1169         if( is_array( $wgForceUIMsgAsContentMsg ) &&
1170                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
1171         {
1172                 $forcontent = false;
1173         }
1174         return wfMsgReal( $key, $args, true, $forcontent );
1175 }
1176
1177 /**
1178  * Same as above except doesn't transform the message
1179  *
1180  * @param $key String
1181  * @return String
1182  */
1183 function wfMsgForContentNoTrans( $key ) {
1184         global $wgForceUIMsgAsContentMsg;
1185         $args = func_get_args();
1186         array_shift( $args );
1187         $forcontent = true;
1188         if( is_array( $wgForceUIMsgAsContentMsg ) &&
1189                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
1190         {
1191                 $forcontent = false;
1192         }
1193         return wfMsgReal( $key, $args, true, $forcontent, false );
1194 }
1195
1196 /**
1197  * Really get a message
1198  *
1199  * @param $key String: key to get.
1200  * @param $args
1201  * @param $useDB Boolean
1202  * @param $forContent Mixed: Language code, or false for user lang, true for content lang.
1203  * @param $transform Boolean: Whether or not to transform the message.
1204  * @return String: the requested message.
1205  */
1206 function wfMsgReal( $key, $args, $useDB = true, $forContent = false, $transform = true ) {
1207         wfProfileIn( __METHOD__ );
1208         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
1209         $message = wfMsgReplaceArgs( $message, $args );
1210         wfProfileOut( __METHOD__ );
1211         return $message;
1212 }
1213
1214 /**
1215  * Fetch a message string value, but don't replace any keys yet.
1216  *
1217  * @param $key String
1218  * @param $useDB Bool
1219  * @param $langCode String: Code of the language to get the message for, or
1220  *                  behaves as a content language switch if it is a boolean.
1221  * @param $transform Boolean: whether to parse magic words, etc.
1222  * @return string
1223  */
1224 function wfMsgGetKey( $key, $useDB = true, $langCode = false, $transform = true ) {
1225         wfRunHooks( 'NormalizeMessageKey', array( &$key, &$useDB, &$langCode, &$transform ) );
1226
1227         $cache = MessageCache::singleton();
1228         $message = $cache->get( $key, $useDB, $langCode );
1229         if( $message === false ) {
1230                 $message = '&lt;' . htmlspecialchars( $key ) . '&gt;';
1231         } elseif ( $transform ) {
1232                 $message = $cache->transform( $message );
1233         }
1234         return $message;
1235 }
1236
1237 /**
1238  * Replace message parameter keys on the given formatted output.
1239  *
1240  * @param $message String
1241  * @param $args Array
1242  * @return string
1243  * @private
1244  */
1245 function wfMsgReplaceArgs( $message, $args ) {
1246         # Fix windows line-endings
1247         # Some messages are split with explode("\n", $msg)
1248         $message = str_replace( "\r", '', $message );
1249
1250         // Replace arguments
1251         if ( count( $args ) ) {
1252                 if ( is_array( $args[0] ) ) {
1253                         $args = array_values( $args[0] );
1254                 }
1255                 $replacementKeys = array();
1256                 foreach( $args as $n => $param ) {
1257                         $replacementKeys['$' . ( $n + 1 )] = $param;
1258                 }
1259                 $message = strtr( $message, $replacementKeys );
1260         }
1261
1262         return $message;
1263 }
1264
1265 /**
1266  * Return an HTML-escaped version of a message.
1267  * Parameter replacements, if any, are done *after* the HTML-escaping,
1268  * so parameters may contain HTML (eg links or form controls). Be sure
1269  * to pre-escape them if you really do want plaintext, or just wrap
1270  * the whole thing in htmlspecialchars().
1271  *
1272  * @param $key String
1273  * @param string ... parameters
1274  * @return string
1275  */
1276 function wfMsgHtml( $key ) {
1277         $args = func_get_args();
1278         array_shift( $args );
1279         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key ) ), $args );
1280 }
1281
1282 /**
1283  * Return an HTML version of message
1284  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
1285  * so parameters may contain HTML (eg links or form controls). Be sure
1286  * to pre-escape them if you really do want plaintext, or just wrap
1287  * the whole thing in htmlspecialchars().
1288  *
1289  * @param $key String
1290  * @param string ... parameters
1291  * @return string
1292  */
1293 function wfMsgWikiHtml( $key ) {
1294         $args = func_get_args();
1295         array_shift( $args );
1296         return wfMsgReplaceArgs(
1297                 MessageCache::singleton()->parse( wfMsgGetKey( $key ), null,
1298                 /* can't be set to false */ true, /* interface */ true )->getText(),
1299                 $args );
1300 }
1301
1302 /**
1303  * Returns message in the requested format
1304  * @param $key String: key of the message
1305  * @param $options Array: processing rules. Can take the following options:
1306  *   <i>parse</i>: parses wikitext to HTML
1307  *   <i>parseinline</i>: parses wikitext to HTML and removes the surrounding
1308  *       p's added by parser or tidy
1309  *   <i>escape</i>: filters message through htmlspecialchars
1310  *   <i>escapenoentities</i>: same, but allows entity references like &#160; through
1311  *   <i>replaceafter</i>: parameters are substituted after parsing or escaping
1312  *   <i>parsemag</i>: transform the message using magic phrases
1313  *   <i>content</i>: fetch message for content language instead of interface
1314  * Also can accept a single associative argument, of the form 'language' => 'xx':
1315  *   <i>language</i>: Language object or language code to fetch message for
1316  *       (overriden by <i>content</i>).
1317  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
1318  *
1319  * @return String
1320  */
1321 function wfMsgExt( $key, $options ) {
1322         $args = func_get_args();
1323         array_shift( $args );
1324         array_shift( $args );
1325         $options = (array)$options;
1326
1327         foreach( $options as $arrayKey => $option ) {
1328                 if( !preg_match( '/^[0-9]+|language$/', $arrayKey ) ) {
1329                         # An unknown index, neither numeric nor "language"
1330                         wfWarn( "wfMsgExt called with incorrect parameter key $arrayKey", 1, E_USER_WARNING );
1331                 } elseif( preg_match( '/^[0-9]+$/', $arrayKey ) && !in_array( $option,
1332                 array( 'parse', 'parseinline', 'escape', 'escapenoentities',
1333                 'replaceafter', 'parsemag', 'content' ) ) ) {
1334                         # A numeric index with unknown value
1335                         wfWarn( "wfMsgExt called with incorrect parameter $option", 1, E_USER_WARNING );
1336                 }
1337         }
1338
1339         if( in_array( 'content', $options, true ) ) {
1340                 $forContent = true;
1341                 $langCode = true;
1342                 $langCodeObj = null;
1343         } elseif( array_key_exists( 'language', $options ) ) {
1344                 $forContent = false;
1345                 $langCode = wfGetLangObj( $options['language'] );
1346                 $langCodeObj = $langCode;
1347         } else {
1348                 $forContent = false;
1349                 $langCode = false;
1350                 $langCodeObj = null;
1351         }
1352
1353         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
1354
1355         if( !in_array( 'replaceafter', $options, true ) ) {
1356                 $string = wfMsgReplaceArgs( $string, $args );
1357         }
1358
1359         $messageCache = MessageCache::singleton();
1360         if( in_array( 'parse', $options, true ) ) {
1361                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj )->getText();
1362         } elseif ( in_array( 'parseinline', $options, true ) ) {
1363                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj )->getText();
1364                 $m = array();
1365                 if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
1366                         $string = $m[1];
1367                 }
1368         } elseif ( in_array( 'parsemag', $options, true ) ) {
1369                 $string = $messageCache->transform( $string,
1370                                 !$forContent, $langCodeObj );
1371         }
1372
1373         if ( in_array( 'escape', $options, true ) ) {
1374                 $string = htmlspecialchars ( $string );
1375         } elseif ( in_array( 'escapenoentities', $options, true ) ) {
1376                 $string = Sanitizer::escapeHtmlAllowEntities( $string );
1377         }
1378
1379         if( in_array( 'replaceafter', $options, true ) ) {
1380                 $string = wfMsgReplaceArgs( $string, $args );
1381         }
1382
1383         return $string;
1384 }
1385
1386 /**
1387  * Since wfMsg() and co suck, they don't return false if the message key they
1388  * looked up didn't exist but a XHTML string, this function checks for the
1389  * nonexistance of messages by checking the MessageCache::get() result directly.
1390  *
1391  * @param $key      String: the message key looked up
1392  * @return Boolean True if the message *doesn't* exist.
1393  */
1394 function wfEmptyMsg( $key ) {
1395         return MessageCache::singleton()->get( $key, /*useDB*/true, /*content*/false ) === false;
1396 }
1397
1398 /**
1399  * Throw a debugging exception. This function previously once exited the process,
1400  * but now throws an exception instead, with similar results.
1401  *
1402  * @param $msg String: message shown when dying.
1403  */
1404 function wfDebugDieBacktrace( $msg = '' ) {
1405         throw new MWException( $msg );
1406 }
1407
1408 /**
1409  * Fetch server name for use in error reporting etc.
1410  * Use real server name if available, so we know which machine
1411  * in a server farm generated the current page.
1412  *
1413  * @return string
1414  */
1415 function wfHostname() {
1416         static $host;
1417         if ( is_null( $host ) ) {
1418                 if ( function_exists( 'posix_uname' ) ) {
1419                         // This function not present on Windows
1420                         $uname = posix_uname();
1421                 } else {
1422                         $uname = false;
1423                 }
1424                 if( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1425                         $host = $uname['nodename'];
1426                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1427                         # Windows computer name
1428                         $host = getenv( 'COMPUTERNAME' );
1429                 } else {
1430                         # This may be a virtual server.
1431                         $host = $_SERVER['SERVER_NAME'];
1432                 }
1433         }
1434         return $host;
1435 }
1436
1437 /**
1438  * Returns a HTML comment with the elapsed time since request.
1439  * This method has no side effects.
1440  *
1441  * @return string
1442  */
1443 function wfReportTime() {
1444         global $wgRequestTime, $wgShowHostnames;
1445
1446         $now = wfTime();
1447         $elapsed = $now - $wgRequestTime;
1448
1449         return $wgShowHostnames
1450                 ? sprintf( '<!-- Served by %s in %01.3f secs. -->', wfHostname(), $elapsed )
1451                 : sprintf( '<!-- Served in %01.3f secs. -->', $elapsed );
1452 }
1453
1454 /**
1455  * Safety wrapper for debug_backtrace().
1456  *
1457  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
1458  * murky circumstances, which may be triggered in part by stub objects
1459  * or other fancy talkin'.
1460  *
1461  * Will return an empty array if Zend Optimizer is detected or if
1462  * debug_backtrace is disabled, otherwise the output from
1463  * debug_backtrace() (trimmed).
1464  *
1465  * @param $limit int This parameter can be used to limit the number of stack frames returned
1466  *
1467  * @return array of backtrace information
1468  */
1469 function wfDebugBacktrace( $limit = 0 ) {
1470         static $disabled = null;
1471
1472         if( extension_loaded( 'Zend Optimizer' ) ) {
1473                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
1474                 return array();
1475         }
1476
1477         if ( is_null( $disabled ) ) {
1478                 $disabled = false;
1479                 $functions = explode( ',', ini_get( 'disable_functions' ) );
1480                 $functions = array_map( 'trim', $functions );
1481                 $functions = array_map( 'strtolower', $functions );
1482                 if ( in_array( 'debug_backtrace', $functions ) ) {
1483                         wfDebug( "debug_backtrace is in disabled_functions\n" );
1484                         $disabled = true;
1485                 }
1486         }
1487         if ( $disabled ) {
1488                 return array();
1489         }
1490
1491         if ( $limit && version_compare( PHP_VERSION, '5.4.0', '>=' ) ) {
1492                 return array_slice( debug_backtrace( DEBUG_BACKTRACE_PROVIDE_OBJECT, $limit ), 1 );
1493         } else {
1494                 return array_slice( debug_backtrace(), 1 );
1495         }
1496 }
1497
1498 /**
1499  * Get a debug backtrace as a string
1500  *
1501  * @return string
1502  */
1503 function wfBacktrace() {
1504         global $wgCommandLineMode;
1505
1506         if ( $wgCommandLineMode ) {
1507                 $msg = '';
1508         } else {
1509                 $msg = "<ul>\n";
1510         }
1511         $backtrace = wfDebugBacktrace();
1512         foreach( $backtrace as $call ) {
1513                 if( isset( $call['file'] ) ) {
1514                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
1515                         $file = $f[count( $f ) - 1];
1516                 } else {
1517                         $file = '-';
1518                 }
1519                 if( isset( $call['line'] ) ) {
1520                         $line = $call['line'];
1521                 } else {
1522                         $line = '-';
1523                 }
1524                 if ( $wgCommandLineMode ) {
1525                         $msg .= "$file line $line calls ";
1526                 } else {
1527                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
1528                 }
1529                 if( !empty( $call['class'] ) ) {
1530                         $msg .= $call['class'] . $call['type'];
1531                 }
1532                 $msg .= $call['function'] . '()';
1533
1534                 if ( $wgCommandLineMode ) {
1535                         $msg .= "\n";
1536                 } else {
1537                         $msg .= "</li>\n";
1538                 }
1539         }
1540         if ( $wgCommandLineMode ) {
1541                 $msg .= "\n";
1542         } else {
1543                 $msg .= "</ul>\n";
1544         }
1545
1546         return $msg;
1547 }
1548
1549 /**
1550  * Get the name of the function which called this function
1551  *
1552  * @param $level Int
1553  * @return Bool|string
1554  */
1555 function wfGetCaller( $level = 2 ) {
1556         $backtrace = wfDebugBacktrace( $level );
1557         if ( isset( $backtrace[$level] ) ) {
1558                 return wfFormatStackFrame( $backtrace[$level] );
1559         } else {
1560                 $caller = 'unknown';
1561         }
1562         return $caller;
1563 }
1564
1565 /**
1566  * Return a string consisting of callers in the stack. Useful sometimes
1567  * for profiling specific points.
1568  *
1569  * @param $limit The maximum depth of the stack frame to return, or false for
1570  *               the entire stack.
1571  * @return String
1572  */
1573 function wfGetAllCallers( $limit = 3 ) {
1574         $trace = array_reverse( wfDebugBacktrace() );
1575         if ( !$limit || $limit > count( $trace ) - 1 ) {
1576                 $limit = count( $trace ) - 1;
1577         }
1578         $trace = array_slice( $trace, -$limit - 1, $limit );
1579         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1580 }
1581
1582 /**
1583  * Return a string representation of frame
1584  *
1585  * @param $frame Array
1586  * @return Bool
1587  */
1588 function wfFormatStackFrame( $frame ) {
1589         return isset( $frame['class'] ) ?
1590                 $frame['class'] . '::' . $frame['function'] :
1591                 $frame['function'];
1592 }
1593
1594
1595 /* Some generic result counters, pulled out of SearchEngine */
1596
1597
1598 /**
1599  * @todo document
1600  *
1601  * @param $offset Int
1602  * @param $limit Int
1603  * @return String
1604  */
1605 function wfShowingResults( $offset, $limit ) {
1606         global $wgLang;
1607         return wfMsgExt(
1608                 'showingresults',
1609                 array( 'parseinline' ),
1610                 $wgLang->formatNum( $limit ),
1611                 $wgLang->formatNum( $offset + 1 )
1612         );
1613 }
1614
1615 /**
1616  * Generate (prev x| next x) (20|50|100...) type links for paging
1617  *
1618  * @param $offset String
1619  * @param $limit Integer
1620  * @param $link String
1621  * @param $query String: optional URL query parameter string
1622  * @param $atend Bool: optional param for specified if this is the last page
1623  * @return String
1624  * @deprecated in 1.19; use Language::viewPrevNext() instead
1625  */
1626 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
1627         global $wgLang;
1628
1629         $query = wfCgiToArray( $query );
1630
1631         if( is_object( $link ) ) {
1632                 $title = $link;
1633         } else {
1634                 $title = Title::newFromText( $link );
1635                 if( is_null( $title ) ) {
1636                         return false;
1637                 }
1638         }
1639
1640         return $wgLang->viewPrevNext( $title, $offset, $limit, $query, $atend );
1641 }
1642
1643 /**
1644  * Make a list item, used by various special pages
1645  *
1646  * @param $page String Page link
1647  * @param $details String Text between brackets
1648  * @param $oppositedm Boolean   Add the direction mark opposite to your
1649  *                                                              language, to display text properly
1650  * @return String
1651  * @deprecated since 1.19; use Language::specialList() instead
1652  */
1653 function wfSpecialList( $page, $details, $oppositedm = true ) {
1654         global $wgLang;
1655         return $wgLang->specialList( $page, $details, $oppositedm );
1656 }
1657
1658 /**
1659  * @todo document
1660  * @todo FIXME: We may want to blacklist some broken browsers
1661  *
1662  * @param $force Bool
1663  * @return bool Whereas client accept gzip compression
1664  */
1665 function wfClientAcceptsGzip( $force = false ) {
1666         static $result = null;
1667         if ( $result === null || $force ) {
1668                 $result = false;
1669                 if( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1670                         # @todo FIXME: We may want to blacklist some broken browsers
1671                         $m = array();
1672                         if( preg_match(
1673                                 '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1674                                 $_SERVER['HTTP_ACCEPT_ENCODING'],
1675                                 $m )
1676                         )
1677                         {
1678                                 if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1679                                         $result = false;
1680                                         return $result;
1681                                 }
1682                                 wfDebug( "wfClientAcceptsGzip: client accepts gzip.\n" );
1683                                 $result = true;
1684                         }
1685                 }
1686         }
1687         return $result;
1688 }
1689
1690 /**
1691  * Obtain the offset and limit values from the request string;
1692  * used in special pages
1693  *
1694  * @param $deflimit Int default limit if none supplied
1695  * @param $optionname String Name of a user preference to check against
1696  * @return array
1697  *
1698  */
1699 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
1700         global $wgRequest;
1701         return $wgRequest->getLimitOffset( $deflimit, $optionname );
1702 }
1703
1704 /**
1705  * Escapes the given text so that it may be output using addWikiText()
1706  * without any linking, formatting, etc. making its way through. This
1707  * is achieved by substituting certain characters with HTML entities.
1708  * As required by the callers, <nowiki> is not used.
1709  *
1710  * @param $text String: text to be escaped
1711  * @return String
1712  */
1713 function wfEscapeWikiText( $text ) {
1714         $text = strtr( "\n$text", array(
1715                 '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
1716                 '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
1717                 '{' => '&#123;', '|' => '&#124;', '}' => '&#125;',
1718                 "\n#" => "\n&#35;", "\n*" => "\n&#42;",
1719                 "\n:" => "\n&#58;", "\n;" => "\n&#59;",
1720                 '://' => '&#58;//', 'ISBN ' => 'ISBN&#32;', 'RFC ' => 'RFC&#32;',
1721         ) );
1722         return substr( $text, 1 );
1723 }
1724
1725 /**
1726  * Get the current unix timetstamp with microseconds.  Useful for profiling
1727  * @return Float
1728  */
1729 function wfTime() {
1730         return microtime( true );
1731 }
1732
1733 /**
1734  * Sets dest to source and returns the original value of dest
1735  * If source is NULL, it just returns the value, it doesn't set the variable
1736  * If force is true, it will set the value even if source is NULL
1737  *
1738  * @param $dest Mixed
1739  * @param $source Mixed
1740  * @param $force Bool
1741  * @return Mixed
1742  */
1743 function wfSetVar( &$dest, $source, $force = false ) {
1744         $temp = $dest;
1745         if ( !is_null( $source ) || $force ) {
1746                 $dest = $source;
1747         }
1748         return $temp;
1749 }
1750
1751 /**
1752  * As for wfSetVar except setting a bit
1753  *
1754  * @param $dest Int
1755  * @param $bit Int
1756  * @param $state Bool
1757  */
1758 function wfSetBit( &$dest, $bit, $state = true ) {
1759         $temp = (bool)( $dest & $bit );
1760         if ( !is_null( $state ) ) {
1761                 if ( $state ) {
1762                         $dest |= $bit;
1763                 } else {
1764                         $dest &= ~$bit;
1765                 }
1766         }
1767         return $temp;
1768 }
1769
1770 /**
1771  * A wrapper around the PHP function var_export().
1772  * Either print it or add it to the regular output ($wgOut).
1773  *
1774  * @param $var A PHP variable to dump.
1775  */
1776 function wfVarDump( $var ) {
1777         global $wgOut;
1778         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
1779         if ( headers_sent() || !isset( $wgOut ) || !is_object( $wgOut ) ) {
1780                 print $s;
1781         } else {
1782                 $wgOut->addHTML( $s );
1783         }
1784 }
1785
1786 /**
1787  * Provide a simple HTTP error.
1788  *
1789  * @param $code Int|String
1790  * @param $label String
1791  * @param $desc String
1792  */
1793 function wfHttpError( $code, $label, $desc ) {
1794         global $wgOut;
1795         $wgOut->disable();
1796         header( "HTTP/1.0 $code $label" );
1797         header( "Status: $code $label" );
1798         $wgOut->sendCacheControl();
1799
1800         header( 'Content-type: text/html; charset=utf-8' );
1801         print "<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">".
1802                 '<html><head><title>' .
1803                 htmlspecialchars( $label ) .
1804                 '</title></head><body><h1>' .
1805                 htmlspecialchars( $label ) .
1806                 '</h1><p>' .
1807                 nl2br( htmlspecialchars( $desc ) ) .
1808                 "</p></body></html>\n";
1809 }
1810
1811 /**
1812  * Clear away any user-level output buffers, discarding contents.
1813  *
1814  * Suitable for 'starting afresh', for instance when streaming
1815  * relatively large amounts of data without buffering, or wanting to
1816  * output image files without ob_gzhandler's compression.
1817  *
1818  * The optional $resetGzipEncoding parameter controls suppression of
1819  * the Content-Encoding header sent by ob_gzhandler; by default it
1820  * is left. See comments for wfClearOutputBuffers() for why it would
1821  * be used.
1822  *
1823  * Note that some PHP configuration options may add output buffer
1824  * layers which cannot be removed; these are left in place.
1825  *
1826  * @param $resetGzipEncoding Bool
1827  */
1828 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
1829         if( $resetGzipEncoding ) {
1830                 // Suppress Content-Encoding and Content-Length
1831                 // headers from 1.10+s wfOutputHandler
1832                 global $wgDisableOutputCompression;
1833                 $wgDisableOutputCompression = true;
1834         }
1835         while( $status = ob_get_status() ) {
1836                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
1837                         // Probably from zlib.output_compression or other
1838                         // PHP-internal setting which can't be removed.
1839                         //
1840                         // Give up, and hope the result doesn't break
1841                         // output behavior.
1842                         break;
1843                 }
1844                 if( !ob_end_clean() ) {
1845                         // Could not remove output buffer handler; abort now
1846                         // to avoid getting in some kind of infinite loop.
1847                         break;
1848                 }
1849                 if( $resetGzipEncoding ) {
1850                         if( $status['name'] == 'ob_gzhandler' ) {
1851                                 // Reset the 'Content-Encoding' field set by this handler
1852                                 // so we can start fresh.
1853                                 if ( function_exists( 'header_remove' ) ) {
1854                                         // Available since PHP 5.3.0
1855                                         header_remove( 'Content-Encoding' );
1856                                 } else {
1857                                         // We need to provide a valid content-coding. See bug 28069
1858                                         header( 'Content-Encoding: identity' );
1859                                 }
1860                                 break;
1861                         }
1862                 }
1863         }
1864 }
1865
1866 /**
1867  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
1868  *
1869  * Clear away output buffers, but keep the Content-Encoding header
1870  * produced by ob_gzhandler, if any.
1871  *
1872  * This should be used for HTTP 304 responses, where you need to
1873  * preserve the Content-Encoding header of the real result, but
1874  * also need to suppress the output of ob_gzhandler to keep to spec
1875  * and avoid breaking Firefox in rare cases where the headers and
1876  * body are broken over two packets.
1877  */
1878 function wfClearOutputBuffers() {
1879         wfResetOutputBuffers( false );
1880 }
1881
1882 /**
1883  * Converts an Accept-* header into an array mapping string values to quality
1884  * factors
1885  *
1886  * @param $accept String
1887  * @param $def String default
1888  * @return Array
1889  */
1890 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
1891         # No arg means accept anything (per HTTP spec)
1892         if( !$accept ) {
1893                 return array( $def => 1.0 );
1894         }
1895
1896         $prefs = array();
1897
1898         $parts = explode( ',', $accept );
1899
1900         foreach( $parts as $part ) {
1901                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
1902                 $values = explode( ';', trim( $part ) );
1903                 $match = array();
1904                 if ( count( $values ) == 1 ) {
1905                         $prefs[$values[0]] = 1.0;
1906                 } elseif ( preg_match( '/q\s*=\s*(\d*\.\d+)/', $values[1], $match ) ) {
1907                         $prefs[$values[0]] = floatval( $match[1] );
1908                 }
1909         }
1910
1911         return $prefs;
1912 }
1913
1914 /**
1915  * Checks if a given MIME type matches any of the keys in the given
1916  * array. Basic wildcards are accepted in the array keys.
1917  *
1918  * Returns the matching MIME type (or wildcard) if a match, otherwise
1919  * NULL if no match.
1920  *
1921  * @param $type String
1922  * @param $avail Array
1923  * @return string
1924  * @private
1925  */
1926 function mimeTypeMatch( $type, $avail ) {
1927         if( array_key_exists( $type, $avail ) ) {
1928                 return $type;
1929         } else {
1930                 $parts = explode( '/', $type );
1931                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
1932                         return $parts[0] . '/*';
1933                 } elseif( array_key_exists( '*/*', $avail ) ) {
1934                         return '*/*';
1935                 } else {
1936                         return null;
1937                 }
1938         }
1939 }
1940
1941 /**
1942  * Returns the 'best' match between a client's requested internet media types
1943  * and the server's list of available types. Each list should be an associative
1944  * array of type to preference (preference is a float between 0.0 and 1.0).
1945  * Wildcards in the types are acceptable.
1946  *
1947  * @param $cprefs Array: client's acceptable type list
1948  * @param $sprefs Array: server's offered types
1949  * @return string
1950  *
1951  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
1952  * XXX: generalize to negotiate other stuff
1953  */
1954 function wfNegotiateType( $cprefs, $sprefs ) {
1955         $combine = array();
1956
1957         foreach( array_keys( $sprefs ) as $type ) {
1958                 $parts = explode( '/', $type );
1959                 if( $parts[1] != '*' ) {
1960                         $ckey = mimeTypeMatch( $type, $cprefs );
1961                         if( $ckey ) {
1962                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
1963                         }
1964                 }
1965         }
1966
1967         foreach( array_keys( $cprefs ) as $type ) {
1968                 $parts = explode( '/', $type );
1969                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
1970                         $skey = mimeTypeMatch( $type, $sprefs );
1971                         if( $skey ) {
1972                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
1973                         }
1974                 }
1975         }
1976
1977         $bestq = 0;
1978         $besttype = null;
1979
1980         foreach( array_keys( $combine ) as $type ) {
1981                 if( $combine[$type] > $bestq ) {
1982                         $besttype = $type;
1983                         $bestq = $combine[$type];
1984                 }
1985         }
1986
1987         return $besttype;
1988 }
1989
1990 /**
1991  * Reference-counted warning suppression
1992  *
1993  * @param $end Bool
1994  */
1995 function wfSuppressWarnings( $end = false ) {
1996         static $suppressCount = 0;
1997         static $originalLevel = false;
1998
1999         if ( $end ) {
2000                 if ( $suppressCount ) {
2001                         --$suppressCount;
2002                         if ( !$suppressCount ) {
2003                                 error_reporting( $originalLevel );
2004                         }
2005                 }
2006         } else {
2007                 if ( !$suppressCount ) {
2008                         // E_DEPRECATED is undefined in PHP 5.2
2009                         if( !defined( 'E_DEPRECATED' ) ) {
2010                                 define( 'E_DEPRECATED', 8192 );
2011                         }
2012                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE | E_USER_WARNING | E_USER_NOTICE | E_DEPRECATED ) );
2013                 }
2014                 ++$suppressCount;
2015         }
2016 }
2017
2018 /**
2019  * Restore error level to previous value
2020  */
2021 function wfRestoreWarnings() {
2022         wfSuppressWarnings( true );
2023 }
2024
2025 # Autodetect, convert and provide timestamps of various types
2026
2027 /**
2028  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
2029  */
2030 define( 'TS_UNIX', 0 );
2031
2032 /**
2033  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
2034  */
2035 define( 'TS_MW', 1 );
2036
2037 /**
2038  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
2039  */
2040 define( 'TS_DB', 2 );
2041
2042 /**
2043  * RFC 2822 format, for E-mail and HTTP headers
2044  */
2045 define( 'TS_RFC2822', 3 );
2046
2047 /**
2048  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
2049  *
2050  * This is used by Special:Export
2051  */
2052 define( 'TS_ISO_8601', 4 );
2053
2054 /**
2055  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
2056  *
2057  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
2058  *       DateTime tag and page 36 for the DateTimeOriginal and
2059  *       DateTimeDigitized tags.
2060  */
2061 define( 'TS_EXIF', 5 );
2062
2063 /**
2064  * Oracle format time.
2065  */
2066 define( 'TS_ORACLE', 6 );
2067
2068 /**
2069  * Postgres format time.
2070  */
2071 define( 'TS_POSTGRES', 7 );
2072
2073 /**
2074  * DB2 format time
2075  */
2076 define( 'TS_DB2', 8 );
2077
2078 /**
2079  * ISO 8601 basic format with no timezone: 19860209T200000Z.  This is used by ResourceLoader
2080  */
2081 define( 'TS_ISO_8601_BASIC', 9 );
2082
2083 /**
2084  * Get a timestamp string in one of various formats
2085  *
2086  * @param $outputtype Mixed: A timestamp in one of the supported formats, the
2087  *                    function will autodetect which format is supplied and act
2088  *                    accordingly.
2089  * @param $ts Mixed: the timestamp to convert or 0 for the current timestamp
2090  * @return Mixed: String / false The same date in the format specified in $outputtype or false
2091  */
2092 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
2093         $uts = 0;
2094         $da = array();
2095         $strtime = '';
2096
2097         if ( !$ts ) { // We want to catch 0, '', null... but not date strings starting with a letter.
2098                 $uts = time();
2099                 $strtime = "@$uts";
2100         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2101                 # TS_DB
2102         } elseif ( preg_match( '/^(\d{4}):(\d\d):(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2103                 # TS_EXIF
2104         } elseif ( preg_match( '/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/D', $ts, $da ) ) {
2105                 # TS_MW
2106         } elseif ( preg_match( '/^-?\d{1,13}$/D', $ts ) ) {
2107                 # TS_UNIX
2108                 $uts = $ts;
2109                 $strtime = "@$ts"; // Undocumented?
2110         } elseif ( preg_match( '/^\d{2}-\d{2}-\d{4} \d{2}:\d{2}:\d{2}.\d{6}$/', $ts ) ) {
2111                 # TS_ORACLE // session altered to DD-MM-YYYY HH24:MI:SS.FF6
2112                 $strtime = preg_replace( '/(\d\d)\.(\d\d)\.(\d\d)(\.(\d+))?/', "$1:$2:$3",
2113                                 str_replace( '+00:00', 'UTC', $ts ) );
2114         } elseif ( preg_match( '/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2115                 # TS_ISO_8601
2116         } elseif ( preg_match( '/^(\d{4})(\d{2})(\d{2})T(\d{2})(\d{2})(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2117                 #TS_ISO_8601_BASIC
2118         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d*[\+\- ](\d\d)$/', $ts, $da ) ) {
2119                 # TS_POSTGRES
2120         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d* GMT$/', $ts, $da ) ) {
2121                 # TS_POSTGRES
2122         } elseif (preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.\d\d\d$/', $ts, $da ) ) {
2123                 # TS_DB2
2124         } elseif ( preg_match( '/^[ \t\r\n]*([A-Z][a-z]{2},[ \t\r\n]*)?' . # Day of week
2125                                                         '\d\d?[ \t\r\n]*[A-Z][a-z]{2}[ \t\r\n]*\d{2}(?:\d{2})?' .  # dd Mon yyyy
2126                                                         '[ \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
2127                 # TS_RFC2822, accepting a trailing comment. See http://www.squid-cache.org/mail-archive/squid-users/200307/0122.html / r77171
2128                 # The regex is a superset of rfc2822 for readability
2129                 $strtime = strtok( $ts, ';' );
2130         } 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 ) ) {
2131                 # TS_RFC850
2132                 $strtime = $ts;
2133         } 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 ) ) {
2134                 # asctime
2135                 $strtime = $ts;
2136         } else {
2137                 # Bogus value...
2138                 wfDebug("wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n");
2139
2140                 return false;
2141         }
2142
2143         static $formats = array(
2144                 TS_UNIX => 'U',
2145                 TS_MW => 'YmdHis',
2146                 TS_DB => 'Y-m-d H:i:s',
2147                 TS_ISO_8601 => 'Y-m-d\TH:i:s\Z',
2148                 TS_ISO_8601_BASIC => 'Ymd\THis\Z',
2149                 TS_EXIF => 'Y:m:d H:i:s', // This shouldn't ever be used, but is included for completeness
2150                 TS_RFC2822 => 'D, d M Y H:i:s',
2151                 TS_ORACLE => 'd-m-Y H:i:s.000000', // Was 'd-M-y h.i.s A' . ' +00:00' before r51500
2152                 TS_POSTGRES => 'Y-m-d H:i:s',
2153                 TS_DB2 => 'Y-m-d H:i:s',
2154         );
2155
2156         if ( !isset( $formats[$outputtype] ) ) {
2157                 throw new MWException( 'wfTimestamp() called with illegal output type.' );
2158         }
2159
2160         if ( function_exists( "date_create" ) ) {
2161                 if ( count( $da ) ) {
2162                         $ds = sprintf("%04d-%02d-%02dT%02d:%02d:%02d.00+00:00",
2163                                 (int)$da[1], (int)$da[2], (int)$da[3],
2164                                 (int)$da[4], (int)$da[5], (int)$da[6]);
2165
2166                         $d = date_create( $ds, new DateTimeZone( 'GMT' ) );
2167                 } elseif ( $strtime ) {
2168                         $d = date_create( $strtime, new DateTimeZone( 'GMT' ) );
2169                 } else {
2170                         return false;
2171                 }
2172
2173                 if ( !$d ) {
2174                         wfDebug("wfTimestamp() fed bogus time value: $outputtype; $ts\n");
2175                         return false;
2176                 }
2177
2178                 $output = $d->format( $formats[$outputtype] );
2179         } else {
2180                 if ( count( $da ) ) {
2181                         // Warning! gmmktime() acts oddly if the month or day is set to 0
2182                         // We may want to handle that explicitly at some point
2183                         $uts = gmmktime( (int)$da[4], (int)$da[5], (int)$da[6],
2184                                 (int)$da[2], (int)$da[3], (int)$da[1] );
2185                 } elseif ( $strtime ) {
2186                         $uts = strtotime( $strtime );
2187                 }
2188
2189                 if ( $uts === false ) {
2190                         wfDebug("wfTimestamp() can't parse the timestamp (non 32-bit time? Update php): $outputtype; $ts\n");
2191                         return false;
2192                 }
2193
2194                 if ( TS_UNIX == $outputtype ) {
2195                         return $uts;
2196                 }
2197                 $output = gmdate( $formats[$outputtype], $uts );
2198         }
2199
2200         if ( ( $outputtype == TS_RFC2822 ) || ( $outputtype == TS_POSTGRES ) ) {
2201                 $output .= ' GMT';
2202         }
2203
2204         return $output;
2205 }
2206
2207 /**
2208  * Return a formatted timestamp, or null if input is null.
2209  * For dealing with nullable timestamp columns in the database.
2210  *
2211  * @param $outputtype Integer
2212  * @param $ts String
2213  * @return String
2214  */
2215 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2216         if( is_null( $ts ) ) {
2217                 return null;
2218         } else {
2219                 return wfTimestamp( $outputtype, $ts );
2220         }
2221 }
2222
2223 /**
2224  * Convenience function; returns MediaWiki timestamp for the present time.
2225  *
2226  * @return string
2227  */
2228 function wfTimestampNow() {
2229         # return NOW
2230         return wfTimestamp( TS_MW, time() );
2231 }
2232
2233 /**
2234  * Check if the operating system is Windows
2235  *
2236  * @return Bool: true if it's Windows, False otherwise.
2237  */
2238 function wfIsWindows() {
2239         static $isWindows = null;
2240         if ( $isWindows === null ) {
2241                 $isWindows = substr( php_uname(), 0, 7 ) == 'Windows';
2242         }
2243         return $isWindows;
2244 }
2245
2246 /**
2247  * Check if we are running under HipHop
2248  *
2249  * @return Bool
2250  */
2251 function wfIsHipHop() {
2252         return function_exists( 'hphp_thread_set_warmup_enabled' );
2253 }
2254
2255 /**
2256  * Swap two variables
2257  *
2258  * @param $x Mixed
2259  * @param $y Mixed
2260  */
2261 function swap( &$x, &$y ) {
2262         $z = $x;
2263         $x = $y;
2264         $y = $z;
2265 }
2266
2267 /**
2268  * Tries to get the system directory for temporary files. The TMPDIR, TMP, and
2269  * TEMP environment variables are then checked in sequence, and if none are set
2270  * try sys_get_temp_dir() for PHP >= 5.2.1. All else fails, return /tmp for Unix
2271  * or C:\Windows\Temp for Windows and hope for the best.
2272  * It is common to call it with tempnam().
2273  *
2274  * NOTE: When possible, use instead the tmpfile() function to create
2275  * temporary files to avoid race conditions on file creation, etc.
2276  *
2277  * @return String
2278  */
2279 function wfTempDir() {
2280         foreach( array( 'TMPDIR', 'TMP', 'TEMP' ) as $var ) {
2281                 $tmp = getenv( $var );
2282                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
2283                         return $tmp;
2284                 }
2285         }
2286         if( function_exists( 'sys_get_temp_dir' ) ) {
2287                 return sys_get_temp_dir();
2288         }
2289         # Usual defaults
2290         return wfIsWindows() ? 'C:\Windows\Temp' : '/tmp';
2291 }
2292
2293 /**
2294  * Make directory, and make all parent directories if they don't exist
2295  *
2296  * @param $dir String: full path to directory to create
2297  * @param $mode Integer: chmod value to use, default is $wgDirectoryMode
2298  * @param $caller String: optional caller param for debugging.
2299  * @return bool
2300  */
2301 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2302         global $wgDirectoryMode;
2303
2304         if ( !is_null( $caller ) ) {
2305                 wfDebug( "$caller: called wfMkdirParents($dir)\n" );
2306         }
2307
2308         if( strval( $dir ) === '' || file_exists( $dir ) ) {
2309                 return true;
2310         }
2311
2312         $dir = str_replace( array( '\\', '/' ), DIRECTORY_SEPARATOR, $dir );
2313
2314         if ( is_null( $mode ) ) {
2315                 $mode = $wgDirectoryMode;
2316         }
2317
2318         // Turn off the normal warning, we're doing our own below
2319         wfSuppressWarnings();
2320         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2321         wfRestoreWarnings();
2322
2323         if( !$ok ) {
2324                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2325                 trigger_error( __FUNCTION__ . ": failed to mkdir \"$dir\" mode $mode", E_USER_WARNING );
2326         }
2327         return $ok;
2328 }
2329
2330 /**
2331  * Increment a statistics counter
2332  *
2333  * @param $key String
2334  * @param $count Int
2335  */
2336 function wfIncrStats( $key, $count = 1 ) {
2337         global $wgStatsMethod;
2338
2339         $count = intval( $count );
2340
2341         if( $wgStatsMethod == 'udp' ) {
2342                 global $wgUDPProfilerHost, $wgUDPProfilerPort, $wgDBname, $wgAggregateStatsID;
2343                 static $socket;
2344
2345                 $id = $wgAggregateStatsID !== false ? $wgAggregateStatsID : $wgDBname;
2346
2347                 if ( !$socket ) {
2348                         $socket = socket_create( AF_INET, SOCK_DGRAM, SOL_UDP );
2349                         $statline = "stats/{$id} - {$count} 1 1 1 1 -total\n";
2350                         socket_sendto(
2351                                 $socket,
2352                                 $statline,
2353                                 strlen( $statline ),
2354                                 0,
2355                                 $wgUDPProfilerHost,
2356                                 $wgUDPProfilerPort
2357                         );
2358                 }
2359                 $statline = "stats/{$id} - {$count} 1 1 1 1 {$key}\n";
2360                 wfSuppressWarnings();
2361                 socket_sendto(
2362                         $socket,
2363                         $statline,
2364                         strlen( $statline ),
2365                         0,
2366                         $wgUDPProfilerHost,
2367                         $wgUDPProfilerPort
2368                 );
2369                 wfRestoreWarnings();
2370         } elseif( $wgStatsMethod == 'cache' ) {
2371                 global $wgMemc;
2372                 $key = wfMemcKey( 'stats', $key );
2373                 if ( is_null( $wgMemc->incr( $key, $count ) ) ) {
2374                         $wgMemc->add( $key, $count );
2375                 }
2376         } else {
2377                 // Disabled
2378         }
2379 }
2380
2381 /**
2382  * @param $nr Mixed: the number to format
2383  * @param $acc Integer: the number of digits after the decimal point, default 2
2384  * @param $round Boolean: whether or not to round the value, default true
2385  * @return float
2386  */
2387 function wfPercent( $nr, $acc = 2, $round = true ) {
2388         $ret = sprintf( "%.${acc}f", $nr );
2389         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2390 }
2391
2392 /**
2393  * Find out whether or not a mixed variable exists in a string
2394  *
2395  * @param $needle String
2396  * @param $str String
2397  * @param $insensitive Boolean
2398  * @return Boolean
2399  */
2400 function in_string( $needle, $str, $insensitive = false ) {
2401         $func = 'strpos';
2402         if( $insensitive ) $func = 'stripos';
2403
2404         return $func( $str, $needle ) !== false;
2405 }
2406
2407 /**
2408  * Safety wrapper around ini_get() for boolean settings.
2409  * The values returned from ini_get() are pre-normalized for settings
2410  * set via php.ini or php_flag/php_admin_flag... but *not*
2411  * for those set via php_value/php_admin_value.
2412  *
2413  * It's fairly common for people to use php_value instead of php_flag,
2414  * which can leave you with an 'off' setting giving a false positive
2415  * for code that just takes the ini_get() return value as a boolean.
2416  *
2417  * To make things extra interesting, setting via php_value accepts
2418  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2419  * Unrecognized values go false... again opposite PHP's own coercion
2420  * from string to bool.
2421  *
2422  * Luckily, 'properly' set settings will always come back as '0' or '1',
2423  * so we only have to worry about them and the 'improper' settings.
2424  *
2425  * I frickin' hate PHP... :P
2426  *
2427  * @param $setting String
2428  * @return Bool
2429  */
2430 function wfIniGetBool( $setting ) {
2431         $val = ini_get( $setting );
2432         // 'on' and 'true' can't have whitespace around them, but '1' can.
2433         return strtolower( $val ) == 'on'
2434                 || strtolower( $val ) == 'true'
2435                 || strtolower( $val ) == 'yes'
2436                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2437 }
2438
2439 /**
2440  * Wrapper function for PHP's dl(). This doesn't work in most situations from
2441  * PHP 5.3 onward, and is usually disabled in shared environments anyway.
2442  *
2443  * @param $extension String A PHP extension. The file suffix (.so or .dll)
2444  *                          should be omitted
2445  * @param $fileName String Name of the library, if not $extension.suffix
2446  * @return Bool - Whether or not the extension is loaded
2447  */
2448 function wfDl( $extension, $fileName = null ) {
2449         if( extension_loaded( $extension ) ) {
2450                 return true;
2451         }
2452
2453         $canDl = false;
2454         $sapi = php_sapi_name();
2455         if( version_compare( PHP_VERSION, '5.3.0', '<' ) ||
2456                 $sapi == 'cli' || $sapi == 'cgi' || $sapi == 'embed' )
2457         {
2458                 $canDl = ( function_exists( 'dl' ) && is_callable( 'dl' )
2459                 && wfIniGetBool( 'enable_dl' ) && !wfIniGetBool( 'safe_mode' ) );
2460         }
2461
2462         if( $canDl ) {
2463                 $fileName = $fileName ? $fileName : $extension;
2464                 if( wfIsWindows() ) {
2465                         $fileName = 'php_' . $fileName;
2466                 }
2467                 wfSuppressWarnings();
2468                 dl( $fileName . '.' . PHP_SHLIB_SUFFIX );
2469                 wfRestoreWarnings();
2470         }
2471         return extension_loaded( $extension );
2472 }
2473
2474 /**
2475  * Windows-compatible version of escapeshellarg()
2476  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
2477  * function puts single quotes in regardless of OS.
2478  *
2479  * Also fixes the locale problems on Linux in PHP 5.2.6+ (bug backported to
2480  * earlier distro releases of PHP)
2481  *
2482  * @param varargs
2483  * @return String
2484  */
2485 function wfEscapeShellArg( ) {
2486         wfInitShellLocale();
2487
2488         $args = func_get_args();
2489         $first = true;
2490         $retVal = '';
2491         foreach ( $args as $arg ) {
2492                 if ( !$first ) {
2493                         $retVal .= ' ';
2494                 } else {
2495                         $first = false;
2496                 }
2497
2498                 if ( wfIsWindows() ) {
2499                         // Escaping for an MSVC-style command line parser and CMD.EXE
2500                         // Refs:
2501                         //  * http://web.archive.org/web/20020708081031/http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
2502                         //  * http://technet.microsoft.com/en-us/library/cc723564.aspx
2503                         //  * Bug #13518
2504                         //  * CR r63214
2505                         // Double the backslashes before any double quotes. Escape the double quotes.
2506                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
2507                         $arg = '';
2508                         $iteration = 0;
2509                         foreach ( $tokens as $token ) {
2510                                 if ( $iteration % 2 == 1 ) {
2511                                         // Delimiter, a double quote preceded by zero or more slashes
2512                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
2513                                 } elseif ( $iteration % 4 == 2 ) {
2514                                         // ^ in $token will be outside quotes, need to be escaped
2515                                         $arg .= str_replace( '^', '^^', $token );
2516                                 } else { // $iteration % 4 == 0
2517                                         // ^ in $token will appear inside double quotes, so leave as is
2518                                         $arg .= $token;
2519                                 }
2520                                 $iteration++;
2521                         }
2522                         // Double the backslashes before the end of the string, because
2523                         // we will soon add a quote
2524                         $m = array();
2525                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
2526                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
2527                         }
2528
2529                         // Add surrounding quotes
2530                         $retVal .= '"' . $arg . '"';
2531                 } else {
2532                         $retVal .= escapeshellarg( $arg );
2533                 }
2534         }
2535         return $retVal;
2536 }
2537
2538 /**
2539  * Execute a shell command, with time and memory limits mirrored from the PHP
2540  * configuration if supported.
2541  * @param $cmd String Command line, properly escaped for shell.
2542  * @param &$retval optional, will receive the program's exit code.
2543  *                 (non-zero is usually failure)
2544  * @param $environ Array optional environment variables which should be
2545  *                 added to the executed command environment.
2546  * @return collected stdout as a string (trailing newlines stripped)
2547  */
2548 function wfShellExec( $cmd, &$retval = null, $environ = array() ) {
2549         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize, $wgMaxShellTime;
2550
2551         static $disabled;
2552         if ( is_null( $disabled ) ) {
2553                 $disabled = false;
2554                 if( wfIniGetBool( 'safe_mode' ) ) {
2555                         wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
2556                         $disabled = 'safemode';
2557                 } else {
2558                         $functions = explode( ',', ini_get( 'disable_functions' ) );
2559                         $functions = array_map( 'trim', $functions );
2560                         $functions = array_map( 'strtolower', $functions );
2561                         if ( in_array( 'passthru', $functions ) ) {
2562                                 wfDebug( "passthru is in disabled_functions\n" );
2563                                 $disabled = 'passthru';
2564                         }
2565                 }
2566         }
2567         if ( $disabled ) {
2568                 $retval = 1;
2569                 return $disabled == 'safemode' ?
2570                         'Unable to run external programs in safe mode.' :
2571                         'Unable to run external programs, passthru() is disabled.';
2572         }
2573
2574         wfInitShellLocale();
2575
2576         $envcmd = '';
2577         foreach( $environ as $k => $v ) {
2578                 if ( wfIsWindows() ) {
2579                         /* Surrounding a set in quotes (method used by wfEscapeShellArg) makes the quotes themselves
2580                          * appear in the environment variable, so we must use carat escaping as documented in
2581                          * http://technet.microsoft.com/en-us/library/cc723564.aspx
2582                          * Note however that the quote isn't listed there, but is needed, and the parentheses
2583                          * are listed there but doesn't appear to need it.
2584                          */
2585                         $envcmd .= "set $k=" . preg_replace( '/([&|()<>^"])/', '^\\1', $v ) . '&& ';
2586                 } else {
2587                         /* Assume this is a POSIX shell, thus required to accept variable assignments before the command
2588                          * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_09_01
2589                          */
2590                         $envcmd .= "$k=" . escapeshellarg( $v ) . ' ';
2591                 }
2592         }
2593         $cmd = $envcmd . $cmd;
2594
2595         if ( wfIsWindows() ) {
2596                 if ( version_compare( PHP_VERSION, '5.3.0', '<' ) && /* Fixed in 5.3.0 :) */
2597                         ( version_compare( PHP_VERSION, '5.2.1', '>=' ) || php_uname( 's' ) == 'Windows NT' ) )
2598                 {
2599                         # Hack to work around PHP's flawed invocation of cmd.exe
2600                         # http://news.php.net/php.internals/21796
2601                         # Windows 9x doesn't accept any kind of quotes
2602                         $cmd = '"' . $cmd . '"';
2603                 }
2604         } elseif ( php_uname( 's' ) == 'Linux' ) {
2605                 $time = intval( $wgMaxShellTime );
2606                 $mem = intval( $wgMaxShellMemory );
2607                 $filesize = intval( $wgMaxShellFileSize );
2608
2609                 if ( $time > 0 && $mem > 0 ) {
2610                         $script = "$IP/bin/ulimit4.sh";
2611                         if ( is_executable( $script ) ) {
2612                                 $cmd = '/bin/bash ' . escapeshellarg( $script ) . " $time $mem $filesize " . escapeshellarg( $cmd );
2613                         }
2614                 }
2615         }
2616         wfDebug( "wfShellExec: $cmd\n" );
2617
2618         $retval = 1; // error by default?
2619         ob_start();
2620         passthru( $cmd, $retval );
2621         $output = ob_get_contents();
2622         ob_end_clean();
2623
2624         if ( $retval == 127 ) {
2625                 wfDebugLog( 'exec', "Possibly missing executable file: $cmd\n" );
2626         }
2627         return $output;
2628 }
2629
2630 /**
2631  * Workaround for http://bugs.php.net/bug.php?id=45132
2632  * escapeshellarg() destroys non-ASCII characters if LANG is not a UTF-8 locale
2633  */
2634 function wfInitShellLocale() {
2635         static $done = false;
2636         if ( $done ) {
2637                 return;
2638         }
2639         $done = true;
2640         global $wgShellLocale;
2641         if ( !wfIniGetBool( 'safe_mode' ) ) {
2642                 putenv( "LC_CTYPE=$wgShellLocale" );
2643                 setlocale( LC_CTYPE, $wgShellLocale );
2644         }
2645 }
2646
2647 /**
2648  * Generate a shell-escaped command line string to run a maintenance script.
2649  * Note that $parameters should be a flat array and an option with an argument
2650  * should consist of two consecutive items in the array (do not use "--option value").
2651  * @param $script string MediaWiki maintenance script path
2652  * @param $parameters Array Arguments and options to the script
2653  * @param $options Array Associative array of options:
2654  *              'php': The path to the php executable
2655  *              'wrapper': Path to a PHP wrapper to handle the maintenance script
2656  * @return Array
2657  */
2658 function wfShellMaintenanceCmd( $script, array $parameters = array(), array $options = array() ) {
2659         global $wgPhpCli;
2660         // Give site config file a chance to run the script in a wrapper.
2661         // The caller may likely want to call wfBasename() on $script.
2662         wfRunHooks( 'wfShellMaintenanceCmd', array( &$script, &$parameters, &$options ) );
2663         $cmd = isset( $options['php'] ) ? array( $options['php'] ) : array( $wgPhpCli );
2664         if ( isset( $options['wrapper'] ) ) {
2665                 $cmd[] = $options['wrapper'];
2666         }
2667         $cmd[] = $script;
2668         // Escape each parameter for shell
2669         return implode( " ", array_map( 'wfEscapeShellArg', array_merge( $cmd, $parameters ) ) );
2670 }
2671
2672 /**
2673  * wfMerge attempts to merge differences between three texts.
2674  * Returns true for a clean merge and false for failure or a conflict.
2675  *
2676  * @param $old String
2677  * @param $mine String
2678  * @param $yours String
2679  * @param $result String
2680  * @return Bool
2681  */
2682 function wfMerge( $old, $mine, $yours, &$result ) {
2683         global $wgDiff3;
2684
2685         # This check may also protect against code injection in
2686         # case of broken installations.
2687         wfSuppressWarnings();
2688         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
2689         wfRestoreWarnings();
2690
2691         if( !$haveDiff3 ) {
2692                 wfDebug( "diff3 not found\n" );
2693                 return false;
2694         }
2695
2696         # Make temporary files
2697         $td = wfTempDir();
2698         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
2699         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
2700         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
2701
2702         fwrite( $oldtextFile, $old );
2703         fclose( $oldtextFile );
2704         fwrite( $mytextFile, $mine );
2705         fclose( $mytextFile );
2706         fwrite( $yourtextFile, $yours );
2707         fclose( $yourtextFile );
2708
2709         # Check for a conflict
2710         $cmd = $wgDiff3 . ' -a --overlap-only ' .
2711                 wfEscapeShellArg( $mytextName ) . ' ' .
2712                 wfEscapeShellArg( $oldtextName ) . ' ' .
2713                 wfEscapeShellArg( $yourtextName );
2714         $handle = popen( $cmd, 'r' );
2715
2716         if( fgets( $handle, 1024 ) ) {
2717                 $conflict = true;
2718         } else {
2719                 $conflict = false;
2720         }
2721         pclose( $handle );
2722
2723         # Merge differences
2724         $cmd = $wgDiff3 . ' -a -e --merge ' .
2725                 wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
2726         $handle = popen( $cmd, 'r' );
2727         $result = '';
2728         do {
2729                 $data = fread( $handle, 8192 );
2730                 if ( strlen( $data ) == 0 ) {
2731                         break;
2732                 }
2733                 $result .= $data;
2734         } while ( true );
2735         pclose( $handle );
2736         unlink( $mytextName );
2737         unlink( $oldtextName );
2738         unlink( $yourtextName );
2739
2740         if ( $result === '' && $old !== '' && !$conflict ) {
2741                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
2742                 $conflict = true;
2743         }
2744         return !$conflict;
2745 }
2746
2747 /**
2748  * Returns unified plain-text diff of two texts.
2749  * Useful for machine processing of diffs.
2750  *
2751  * @param $before String: the text before the changes.
2752  * @param $after String: the text after the changes.
2753  * @param $params String: command-line options for the diff command.
2754  * @return String: unified diff of $before and $after
2755  */
2756 function wfDiff( $before, $after, $params = '-u' ) {
2757         if ( $before == $after ) {
2758                 return '';
2759         }
2760
2761         global $wgDiff;
2762         wfSuppressWarnings();
2763         $haveDiff = $wgDiff && file_exists( $wgDiff );
2764         wfRestoreWarnings();
2765
2766         # This check may also protect against code injection in
2767         # case of broken installations.
2768         if( !$haveDiff ) {
2769                 wfDebug( "diff executable not found\n" );
2770                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
2771                 $format = new UnifiedDiffFormatter();
2772                 return $format->format( $diffs );
2773         }
2774
2775         # Make temporary files
2776         $td = wfTempDir();
2777         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
2778         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
2779
2780         fwrite( $oldtextFile, $before );
2781         fclose( $oldtextFile );
2782         fwrite( $newtextFile, $after );
2783         fclose( $newtextFile );
2784
2785         // Get the diff of the two files
2786         $cmd = "$wgDiff " . $params . ' ' . wfEscapeShellArg( $oldtextName, $newtextName );
2787
2788         $h = popen( $cmd, 'r' );
2789
2790         $diff = '';
2791
2792         do {
2793                 $data = fread( $h, 8192 );
2794                 if ( strlen( $data ) == 0 ) {
2795                         break;
2796                 }
2797                 $diff .= $data;
2798         } while ( true );
2799
2800         // Clean up
2801         pclose( $h );
2802         unlink( $oldtextName );
2803         unlink( $newtextName );
2804
2805         // Kill the --- and +++ lines. They're not useful.
2806         $diff_lines = explode( "\n", $diff );
2807         if ( strpos( $diff_lines[0], '---' ) === 0 ) {
2808                 unset( $diff_lines[0] );
2809         }
2810         if ( strpos( $diff_lines[1], '+++' ) === 0 ) {
2811                 unset( $diff_lines[1] );
2812         }
2813
2814         $diff = implode( "\n", $diff_lines );
2815
2816         return $diff;
2817 }
2818
2819 /**
2820  * This function works like "use VERSION" in Perl, the program will die with a
2821  * backtrace if the current version of PHP is less than the version provided
2822  *
2823  * This is useful for extensions which due to their nature are not kept in sync
2824  * with releases, and might depend on other versions of PHP than the main code
2825  *
2826  * Note: PHP might die due to parsing errors in some cases before it ever
2827  *       manages to call this function, such is life
2828  *
2829  * @see perldoc -f use
2830  *
2831  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2832  *                 a float
2833  */
2834 function wfUsePHP( $req_ver ) {
2835         $php_ver = PHP_VERSION;
2836
2837         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
2838                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
2839         }
2840 }
2841
2842 /**
2843  * This function works like "use VERSION" in Perl except it checks the version
2844  * of MediaWiki, the program will die with a backtrace if the current version
2845  * of MediaWiki is less than the version provided.
2846  *
2847  * This is useful for extensions which due to their nature are not kept in sync
2848  * with releases
2849  *
2850  * @see perldoc -f use
2851  *
2852  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2853  *                 a float
2854  */
2855 function wfUseMW( $req_ver ) {
2856         global $wgVersion;
2857
2858         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
2859                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
2860         }
2861 }
2862
2863 /**
2864  * Return the final portion of a pathname.
2865  * Reimplemented because PHP5's basename() is buggy with multibyte text.
2866  * http://bugs.php.net/bug.php?id=33898
2867  *
2868  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
2869  * We'll consider it so always, as we don't want \s in our Unix paths either.
2870  *
2871  * @param $path String
2872  * @param $suffix String: to remove if present
2873  * @return String
2874  */
2875 function wfBaseName( $path, $suffix = '' ) {
2876         $encSuffix = ( $suffix == '' )
2877                 ? ''
2878                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
2879         $matches = array();
2880         if( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2881                 return $matches[1];
2882         } else {
2883                 return '';
2884         }
2885 }
2886
2887 /**
2888  * Generate a relative path name to the given file.
2889  * May explode on non-matching case-insensitive paths,
2890  * funky symlinks, etc.
2891  *
2892  * @param $path String: absolute destination path including target filename
2893  * @param $from String: Absolute source path, directory only
2894  * @return String
2895  */
2896 function wfRelativePath( $path, $from ) {
2897         // Normalize mixed input on Windows...
2898         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2899         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2900
2901         // Trim trailing slashes -- fix for drive root
2902         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2903         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2904
2905         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2906         $against = explode( DIRECTORY_SEPARATOR, $from );
2907
2908         if( $pieces[0] !== $against[0] ) {
2909                 // Non-matching Windows drive letters?
2910                 // Return a full path.
2911                 return $path;
2912         }
2913
2914         // Trim off common prefix
2915         while( count( $pieces ) && count( $against )
2916                 && $pieces[0] == $against[0] ) {
2917                 array_shift( $pieces );
2918                 array_shift( $against );
2919         }
2920
2921         // relative dots to bump us to the parent
2922         while( count( $against ) ) {
2923                 array_unshift( $pieces, '..' );
2924                 array_shift( $against );
2925         }
2926
2927         array_push( $pieces, wfBaseName( $path ) );
2928
2929         return implode( DIRECTORY_SEPARATOR, $pieces );
2930 }
2931
2932 /**
2933  * Do any deferred updates and clear the list
2934  *
2935  * @deprecated since 1.19
2936  * @see DeferredUpdates::doUpdate()
2937  * @param $commit string
2938  */
2939 function wfDoUpdates( $commit = '' ) {
2940         DeferredUpdates::doUpdates( $commit );
2941 }
2942
2943 /**
2944  * Convert an arbitrarily-long digit string from one numeric base
2945  * to another, optionally zero-padding to a minimum column width.
2946  *
2947  * Supports base 2 through 36; digit values 10-36 are represented
2948  * as lowercase letters a-z. Input is case-insensitive.
2949  *
2950  * @param $input String: of digits
2951  * @param $sourceBase Integer: 2-36
2952  * @param $destBase Integer: 2-36
2953  * @param $pad Integer: 1 or greater
2954  * @param $lowercase Boolean
2955  * @return String or false on invalid input
2956  */
2957 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1, $lowercase = true ) {
2958         $input = strval( $input );
2959         if( $sourceBase < 2 ||
2960                 $sourceBase > 36 ||
2961                 $destBase < 2 ||
2962                 $destBase > 36 ||
2963                 $pad < 1 ||
2964                 $sourceBase != intval( $sourceBase ) ||
2965                 $destBase != intval( $destBase ) ||
2966                 $pad != intval( $pad ) ||
2967                 !is_string( $input ) ||
2968                 $input == '' ) {
2969                 return false;
2970         }
2971         $digitChars = ( $lowercase ) ? '0123456789abcdefghijklmnopqrstuvwxyz' : '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
2972         $inDigits = array();
2973         $outChars = '';
2974
2975         // Decode and validate input string
2976         $input = strtolower( $input );
2977         for( $i = 0; $i < strlen( $input ); $i++ ) {
2978                 $n = strpos( $digitChars, $input[$i] );
2979                 if( $n === false || $n > $sourceBase ) {
2980                         return false;
2981                 }
2982                 $inDigits[] = $n;
2983         }
2984
2985         // Iterate over the input, modulo-ing out an output digit
2986         // at a time until input is gone.
2987         while( count( $inDigits ) ) {
2988                 $work = 0;
2989                 $workDigits = array();
2990
2991                 // Long division...
2992                 foreach( $inDigits as $digit ) {
2993                         $work *= $sourceBase;
2994                         $work += $digit;
2995
2996                         if( $work < $destBase ) {
2997                                 // Gonna need to pull another digit.
2998                                 if( count( $workDigits ) ) {
2999                                         // Avoid zero-padding; this lets us find
3000                                         // the end of the input very easily when
3001                                         // length drops to zero.
3002                                         $workDigits[] = 0;
3003                                 }
3004                         } else {
3005                                 // Finally! Actual division!
3006                                 $workDigits[] = intval( $work / $destBase );
3007
3008                                 // Isn't it annoying that most programming languages
3009                                 // don't have a single divide-and-remainder operator,
3010                                 // even though the CPU implements it that way?
3011                                 $work = $work % $destBase;
3012                         }
3013                 }
3014
3015                 // All that division leaves us with a remainder,
3016                 // which is conveniently our next output digit.
3017                 $outChars .= $digitChars[$work];
3018
3019                 // And we continue!
3020                 $inDigits = $workDigits;
3021         }
3022
3023         while( strlen( $outChars ) < $pad ) {
3024                 $outChars .= '0';
3025         }
3026
3027         return strrev( $outChars );
3028 }
3029
3030 /**
3031  * Create an object with a given name and an array of construct parameters
3032  *
3033  * @param $name String
3034  * @param $p Array: parameters
3035  * @return object
3036  * @deprecated since 1.18, warnings in 1.18, removal in 1.20
3037  */
3038 function wfCreateObject( $name, $p ) {
3039         wfDeprecated( __FUNCTION__ );
3040         return MWFunction::newObj( $name, $p );
3041 }
3042
3043 /**
3044  * @return bool
3045  */
3046 function wfHttpOnlySafe() {
3047         global $wgHttpOnlyBlacklist;
3048
3049         if( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
3050                 foreach( $wgHttpOnlyBlacklist as $regex ) {
3051                         if( preg_match( $regex, $_SERVER['HTTP_USER_AGENT'] ) ) {
3052                                 return false;
3053                         }
3054                 }
3055         }
3056
3057         return true;
3058 }
3059
3060 /**
3061  * Initialise php session
3062  *
3063  * @param $sessionId Bool
3064  */
3065 function wfSetupSession( $sessionId = false ) {
3066         global $wgSessionsInMemcached, $wgCookiePath, $wgCookieDomain,
3067                         $wgCookieSecure, $wgCookieHttpOnly, $wgSessionHandler;
3068         if( $wgSessionsInMemcached ) {
3069                 if ( !defined( 'MW_COMPILED' ) ) {
3070                         global $IP;
3071                         require_once( "$IP/includes/cache/MemcachedSessions.php" );
3072                 }
3073                 session_set_save_handler( 'memsess_open', 'memsess_close', 'memsess_read',
3074                         'memsess_write', 'memsess_destroy', 'memsess_gc' );
3075
3076                 // It's necessary to register a shutdown function to call session_write_close(),
3077                 // because by the time the request shutdown function for the session module is
3078                 // called, $wgMemc has already been destroyed. Shutdown functions registered
3079                 // this way are called before object destruction.
3080                 register_shutdown_function( 'memsess_write_close' );
3081         } elseif( $wgSessionHandler && $wgSessionHandler != ini_get( 'session.save_handler' ) ) {
3082                 # Only set this if $wgSessionHandler isn't null and session.save_handler
3083                 # hasn't already been set to the desired value (that causes errors)
3084                 ini_set( 'session.save_handler', $wgSessionHandler );
3085         }
3086         $httpOnlySafe = wfHttpOnlySafe() && $wgCookieHttpOnly;
3087         wfDebugLog( 'cookie',
3088                 'session_set_cookie_params: "' . implode( '", "',
3089                         array(
3090                                 0,
3091                                 $wgCookiePath,
3092                                 $wgCookieDomain,
3093                                 $wgCookieSecure,
3094                                 $httpOnlySafe ) ) . '"' );
3095         session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $httpOnlySafe );
3096         session_cache_limiter( 'private, must-revalidate' );
3097         if ( $sessionId ) {
3098                 session_id( $sessionId );
3099         }
3100         wfSuppressWarnings();
3101         session_start();
3102         wfRestoreWarnings();
3103 }
3104
3105 /**
3106  * Get an object from the precompiled serialized directory
3107  *
3108  * @param $name String
3109  * @return Mixed: the variable on success, false on failure
3110  */
3111 function wfGetPrecompiledData( $name ) {
3112         global $IP;
3113
3114         $file = "$IP/serialized/$name";
3115         if ( file_exists( $file ) ) {
3116                 $blob = file_get_contents( $file );
3117                 if ( $blob ) {
3118                         return unserialize( $blob );
3119                 }
3120         }
3121         return false;
3122 }
3123
3124 /**
3125  * Get a cache key
3126  *
3127  * @param varargs
3128  * @return String
3129  */
3130 function wfMemcKey( /*... */ ) {
3131         $args = func_get_args();
3132         $key = wfWikiID() . ':' . implode( ':', $args );
3133         $key = str_replace( ' ', '_', $key );
3134         return $key;
3135 }
3136
3137 /**
3138  * Get a cache key for a foreign DB
3139  *
3140  * @param $db String
3141  * @param $prefix String
3142  * @param varargs String
3143  * @return String
3144  */
3145 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
3146         $args = array_slice( func_get_args(), 2 );
3147         if ( $prefix ) {
3148                 $key = "$db-$prefix:" . implode( ':', $args );
3149         } else {
3150                 $key = $db . ':' . implode( ':', $args );
3151         }
3152         return $key;
3153 }
3154
3155 /**
3156  * Get an ASCII string identifying this wiki
3157  * This is used as a prefix in memcached keys
3158  *
3159  * @return String
3160  */
3161 function wfWikiID() {
3162         global $wgDBprefix, $wgDBname, $wgWikiID;
3163         if ( $wgWikiID !== false ) {
3164                 return $wgWikiID;
3165         } elseif ( $wgDBprefix ) {
3166                 return "$wgDBname-$wgDBprefix";
3167         } else {
3168                 return $wgDBname;
3169         }
3170 }
3171
3172 /**
3173  * Split a wiki ID into DB name and table prefix
3174  *
3175  * @param $wiki String
3176  *
3177  * @return array
3178  */
3179 function wfSplitWikiID( $wiki ) {
3180         $bits = explode( '-', $wiki, 2 );
3181         if ( count( $bits ) < 2 ) {
3182                 $bits[] = '';
3183         }
3184         return $bits;
3185 }
3186
3187 /**
3188  * Get a Database object.
3189  *
3190  * @param $db Integer: index of the connection to get. May be DB_MASTER for the
3191  *            master (for write queries), DB_SLAVE for potentially lagged read
3192  *            queries, or an integer >= 0 for a particular server.
3193  *
3194  * @param $groups Mixed: query groups. An array of group names that this query
3195  *                belongs to. May contain a single string if the query is only
3196  *                in one group.
3197  *
3198  * @param $wiki String: the wiki ID, or false for the current wiki
3199  *
3200  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
3201  * will always return the same object, unless the underlying connection or load
3202  * balancer is manually destroyed.
3203  *
3204  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
3205  * updater to ensure that a proper database is being updated.
3206  *
3207  * @return DatabaseBase
3208  */
3209 function &wfGetDB( $db, $groups = array(), $wiki = false ) {
3210         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
3211 }
3212
3213 /**
3214  * Get a load balancer object.
3215  *
3216  * @param $wiki String: wiki ID, or false for the current wiki
3217  * @return LoadBalancer
3218  */
3219 function wfGetLB( $wiki = false ) {
3220         return wfGetLBFactory()->getMainLB( $wiki );
3221 }
3222
3223 /**
3224  * Get the load balancer factory object
3225  *
3226  * @return LBFactory
3227  */
3228 function &wfGetLBFactory() {
3229         return LBFactory::singleton();
3230 }
3231
3232 /**
3233  * Find a file.
3234  * Shortcut for RepoGroup::singleton()->findFile()
3235  *
3236  * @param $title String or Title object
3237  * @param $options Associative array of options:
3238  *     time:           requested time for an archived image, or false for the
3239  *                     current version. An image object will be returned which was
3240  *                     created at the specified time.
3241  *
3242  *     ignoreRedirect: If true, do not follow file redirects
3243  *
3244  *     private:        If true, return restricted (deleted) files if the current
3245  *                     user is allowed to view them. Otherwise, such files will not
3246  *                     be found.
3247  *
3248  *     bypassCache:    If true, do not use the process-local cache of File objects
3249  *
3250  * @return File, or false if the file does not exist
3251  */
3252 function wfFindFile( $title, $options = array() ) {
3253         return RepoGroup::singleton()->findFile( $title, $options );
3254 }
3255
3256 /**
3257  * Get an object referring to a locally registered file.
3258  * Returns a valid placeholder object if the file does not exist.
3259  *
3260  * @param $title Title or String
3261  * @return File, or null if passed an invalid Title
3262  */
3263 function wfLocalFile( $title ) {
3264         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
3265 }
3266
3267 /**
3268  * Stream a file to the browser. Back-compat alias for StreamFile::stream()
3269  * @deprecated since 1.19
3270  */
3271 function wfStreamFile( $fname, $headers = array() ) {
3272         StreamFile::stream( $fname, $headers );
3273 }
3274
3275 /**
3276  * Should low-performance queries be disabled?
3277  *
3278  * @return Boolean
3279  * @codeCoverageIgnore
3280  */
3281 function wfQueriesMustScale() {
3282         global $wgMiserMode;
3283         return $wgMiserMode
3284                 || ( SiteStats::pages() > 100000
3285                 && SiteStats::edits() > 1000000
3286                 && SiteStats::users() > 10000 );
3287 }
3288
3289 /**
3290  * Get the path to a specified script file, respecting file
3291  * extensions; this is a wrapper around $wgScriptExtension etc.
3292  *
3293  * @param $script String: script filename, sans extension
3294  * @return String
3295  */
3296 function wfScript( $script = 'index' ) {
3297         global $wgScriptPath, $wgScriptExtension;
3298         return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
3299 }
3300
3301 /**
3302  * Get the script URL.
3303  *
3304  * @return script URL
3305  */
3306 function wfGetScriptUrl() {
3307         if( isset( $_SERVER['SCRIPT_NAME'] ) ) {
3308                 #
3309                 # as it was called, minus the query string.
3310                 #
3311                 # Some sites use Apache rewrite rules to handle subdomains,
3312                 # and have PHP set up in a weird way that causes PHP_SELF
3313                 # to contain the rewritten URL instead of the one that the
3314                 # outside world sees.
3315                 #
3316                 # If in this mode, use SCRIPT_URL instead, which mod_rewrite
3317                 # provides containing the "before" URL.
3318                 return $_SERVER['SCRIPT_NAME'];
3319         } else {
3320                 return $_SERVER['URL'];
3321         }
3322 }
3323
3324 /**
3325  * Convenience function converts boolean values into "true"
3326  * or "false" (string) values
3327  *
3328  * @param $value Boolean
3329  * @return String
3330  */
3331 function wfBoolToStr( $value ) {
3332         return $value ? 'true' : 'false';
3333 }
3334
3335 /**
3336  * Load an extension messages file
3337  *
3338  * @deprecated since 1.16, warnings in 1.18, remove in 1.20
3339  * @codeCoverageIgnore
3340  */
3341 function wfLoadExtensionMessages() {
3342         wfDeprecated( __FUNCTION__ );
3343 }
3344
3345 /**
3346  * Get a platform-independent path to the null file, e.g. /dev/null
3347  *
3348  * @return string
3349  */
3350 function wfGetNull() {
3351         return wfIsWindows()
3352                 ? 'NUL'
3353                 : '/dev/null';
3354 }
3355
3356 /**
3357  * Throws a warning that $function is deprecated
3358  *
3359  * @param $function String
3360  * @param $version String
3361  * @return null
3362  */
3363 function wfDeprecated( $function, $version = false ) {
3364         static $functionsWarned = array();
3365         if ( !isset( $functionsWarned[$function] ) ) {
3366                 $functionsWarned[$function] = true;
3367                 if ( $version ) {
3368                         global $wgDeprecationReleaseLimit;
3369                         if ( $wgDeprecationReleaseLimit ) {
3370                                 # Strip -* off the end of $version so that branches can use the
3371                                 # format #.##-branchname to avoid issues if the branch is merged into
3372                                 # a version of MediaWiki later than what it was branched from
3373                                 $comparableVersion = preg_replace( '/-.*$/', '', $version );
3374                                 # If the comparableVersion is larger than our release limit then
3375                                 # skip the warning message for the deprecation
3376                                 if ( version_compare( $wgDeprecationReleaseLimit, $comparableVersion, '<' ) ) {
3377                                         return;
3378                                 }
3379                         }
3380                         wfWarn( "Use of $function was deprecated in $version.", 2 );
3381                 } else {
3382                         wfWarn( "Use of $function is deprecated.", 2 );
3383                 }
3384         }
3385 }
3386
3387 /**
3388  * Send a warning either to the debug log or in a PHP error depending on
3389  * $wgDevelopmentWarnings
3390  *
3391  * @param $msg String: message to send
3392  * @param $callerOffset Integer: number of items to go back in the backtrace to
3393  *        find the correct caller (1 = function calling wfWarn, ...)
3394  * @param $level Integer: PHP error level; only used when $wgDevelopmentWarnings
3395  *        is true
3396  */
3397 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
3398         global $wgDevelopmentWarnings;
3399
3400         $callers = wfDebugBacktrace();
3401         if ( isset( $callers[$callerOffset + 1] ) ) {
3402                 $callerfunc = $callers[$callerOffset + 1];
3403                 $callerfile = $callers[$callerOffset];
3404                 if ( isset( $callerfile['file'] ) && isset( $callerfile['line'] ) ) {
3405                         $file = $callerfile['file'] . ' at line ' . $callerfile['line'];
3406                 } else {
3407                         $file = '(internal function)';
3408                 }
3409                 $func = '';
3410                 if ( isset( $callerfunc['class'] ) ) {
3411                         $func .= $callerfunc['class'] . '::';
3412                 }
3413                 if ( isset( $callerfunc['function'] ) ) {
3414                         $func .= $callerfunc['function'];
3415                 }
3416                 $msg .= " [Called from $func in $file]";
3417         }
3418
3419         if ( $wgDevelopmentWarnings ) {
3420                 trigger_error( $msg, $level );
3421         } else {
3422                 wfDebug( "$msg\n" );
3423         }
3424 }
3425
3426 /**
3427  * Modern version of wfWaitForSlaves(). Instead of looking at replication lag
3428  * and waiting for it to go down, this waits for the slaves to catch up to the
3429  * master position. Use this when updating very large numbers of rows, as
3430  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
3431  * a no-op if there are no slaves.
3432  *
3433  * @param $maxLag Integer (deprecated)
3434  * @param $wiki mixed Wiki identifier accepted by wfGetLB
3435  */
3436 function wfWaitForSlaves( $maxLag = false, $wiki = false ) {
3437         $lb = wfGetLB( $wiki );
3438         // bug 27975 - Don't try to wait for slaves if there are none
3439         // Prevents permission error when getting master position
3440         if ( $lb->getServerCount() > 1 ) {
3441                 $dbw = $lb->getConnection( DB_MASTER );
3442                 $pos = $dbw->getMasterPos();
3443                 $lb->waitForAll( $pos );
3444         }
3445 }
3446
3447 /**
3448  * Used to be used for outputting text in the installer/updater
3449  * @deprecated since 1.18, warnings in 1.18, remove in 1.20
3450  */
3451 function wfOut( $s ) {
3452         wfDeprecated( __METHOD__ );
3453         global $wgCommandLineMode;
3454         if ( $wgCommandLineMode ) {
3455                 echo $s;
3456         } else {
3457                 echo htmlspecialchars( $s );
3458         }
3459         flush();
3460 }
3461
3462 /**
3463  * Count down from $n to zero on the terminal, with a one-second pause
3464  * between showing each number. For use in command-line scripts.
3465  * @codeCoverageIgnore
3466  * @param $n int
3467  */
3468 function wfCountDown( $n ) {
3469         for ( $i = $n; $i >= 0; $i-- ) {
3470                 if ( $i != $n ) {
3471                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3472                 }
3473                 echo $i;
3474                 flush();
3475                 if ( $i ) {
3476                         sleep( 1 );
3477                 }
3478         }
3479         echo "\n";
3480 }
3481
3482 /**
3483  * Generate a random 32-character hexadecimal token.
3484  * @param $salt Mixed: some sort of salt, if necessary, to add to random
3485  *              characters before hashing.
3486  * @return string
3487  * @codeCoverageIgnore
3488  */
3489 function wfGenerateToken( $salt = '' ) {
3490         $salt = serialize( $salt );
3491         return md5( mt_rand( 0, 0x7fffffff ) . $salt );
3492 }
3493
3494 /**
3495  * Replace all invalid characters with -
3496  *
3497  * @param $name Mixed: filename to process
3498  * @return String
3499  */
3500 function wfStripIllegalFilenameChars( $name ) {
3501         global $wgIllegalFileChars;
3502         $name = wfBaseName( $name );
3503         $name = preg_replace(
3504                 "/[^" . Title::legalChars() . "]" .
3505                         ( $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '' ) .
3506                         "/",
3507                 '-',
3508                 $name
3509         );
3510         return $name;
3511 }
3512
3513 /**
3514  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit;
3515  *
3516  * @return Integer value memory was set to.
3517  */
3518 function wfMemoryLimit() {
3519         global $wgMemoryLimit;
3520         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3521         if( $memlimit != -1 ) {
3522                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3523                 if( $conflimit == -1 ) {
3524                         wfDebug( "Removing PHP's memory limit\n" );
3525                         wfSuppressWarnings();
3526                         ini_set( 'memory_limit', $conflimit );
3527                         wfRestoreWarnings();
3528                         return $conflimit;
3529                 } elseif ( $conflimit > $memlimit ) {
3530                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3531                         wfSuppressWarnings();
3532                         ini_set( 'memory_limit', $conflimit );
3533                         wfRestoreWarnings();
3534                         return $conflimit;
3535                 }
3536         }
3537         return $memlimit;
3538 }
3539
3540 /**
3541  * Converts shorthand byte notation to integer form
3542  *
3543  * @param $string String
3544  * @return Integer
3545  */
3546 function wfShorthandToInteger( $string = '' ) {
3547         $string = trim( $string );
3548         if( $string === '' ) {
3549                 return -1;
3550         }
3551         $last = $string[strlen( $string ) - 1];
3552         $val = intval( $string );
3553         switch( $last ) {
3554                 case 'g':
3555                 case 'G':
3556                         $val *= 1024;
3557                         // break intentionally missing
3558                 case 'm':
3559                 case 'M':
3560                         $val *= 1024;
3561                         // break intentionally missing
3562                 case 'k':
3563                 case 'K':
3564                         $val *= 1024;
3565         }
3566
3567         return $val;
3568 }
3569
3570 /**
3571  * Get the normalised IETF language tag
3572  * See unit test for examples.
3573  *
3574  * @param $code String: The language code.
3575  * @return String: The language code which complying with BCP 47 standards.
3576  */
3577 function wfBCP47( $code ) {
3578         $codeSegment = explode( '-', $code );
3579         $codeBCP = array();
3580         foreach ( $codeSegment as $segNo => $seg ) {
3581                 if ( count( $codeSegment ) > 0 ) {
3582                         // when previous segment is x, it is a private segment and should be lc
3583                         if( $segNo > 0 && strtolower( $codeSegment[( $segNo - 1 )] ) == 'x' ) {
3584                                 $codeBCP[$segNo] = strtolower( $seg );
3585                         // ISO 3166 country code
3586                         } elseif ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3587                                 $codeBCP[$segNo] = strtoupper( $seg );
3588                         // ISO 15924 script code
3589                         } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3590                                 $codeBCP[$segNo] = ucfirst( strtolower( $seg ) );
3591                         // Use lowercase for other cases
3592                         } else {
3593                                 $codeBCP[$segNo] = strtolower( $seg );
3594                         }
3595                 } else {
3596                 // Use lowercase for single segment
3597                         $codeBCP[$segNo] = strtolower( $seg );
3598                 }
3599         }
3600         $langCode = implode( '-', $codeBCP );
3601         return $langCode;
3602 }
3603
3604 /**
3605  * Get a cache object.
3606  *
3607  * @param $inputType integer Cache type, one the the CACHE_* constants.
3608  * @return BagOStuff
3609  */
3610 function wfGetCache( $inputType ) {
3611         return ObjectCache::getInstance( $inputType );
3612 }
3613
3614 /**
3615  * Get the main cache object
3616  *
3617  * @return BagOStuff
3618  */
3619 function wfGetMainCache() {
3620         global $wgMainCacheType;
3621         return ObjectCache::getInstance( $wgMainCacheType );
3622 }
3623
3624 /**
3625  * Get the cache object used by the message cache
3626  *
3627  * @return BagOStuff
3628  */
3629 function wfGetMessageCacheStorage() {
3630         global $wgMessageCacheType;
3631         return ObjectCache::getInstance( $wgMessageCacheType );
3632 }
3633
3634 /**
3635  * Get the cache object used by the parser cache
3636  *
3637  * @return BagOStuff
3638  */
3639 function wfGetParserCacheStorage() {
3640         global $wgParserCacheType;
3641         return ObjectCache::getInstance( $wgParserCacheType );
3642 }
3643
3644 /**
3645  * Call hook functions defined in $wgHooks
3646  *
3647  * @param $event String: event name
3648  * @param $args Array: parameters passed to hook functions
3649  * @return Boolean
3650  */
3651 function wfRunHooks( $event, $args = array() ) {
3652         return Hooks::run( $event, $args );
3653 }
3654
3655 /**
3656  * Wrapper around php's unpack.
3657  *
3658  * @param $format String: The format string (See php's docs)
3659  * @param $data: A binary string of binary data
3660  * @param $length integer or false: The minimun length of $data. This is to
3661  *      prevent reading beyond the end of $data. false to disable the check.
3662  *
3663  * Also be careful when using this function to read unsigned 32 bit integer
3664  * because php might make it negative.
3665  *
3666  * @throws MWException if $data not long enough, or if unpack fails
3667  * @return Associative array of the extracted data
3668  */
3669 function wfUnpack( $format, $data, $length=false ) {
3670         if ( $length !== false ) {
3671                 $realLen = strlen( $data );
3672                 if ( $realLen < $length ) {
3673                         throw new MWException( "Tried to use wfUnpack on a "
3674                                 . "string of length $realLen, but needed one "
3675                                 . "of at least length $length."
3676                         );
3677                 }
3678         }
3679
3680         wfSuppressWarnings();
3681         $result = unpack( $format, $data );
3682         wfRestoreWarnings();
3683
3684         if ( $result === false ) {
3685                 // If it cannot extract the packed data.
3686                 throw new MWException( "unpack could not unpack binary data" );
3687         }
3688         return $result;
3689 }