includes/GlobalFunctions.php

   1 <?php
   2 /**
   3  * Global functions used everywhere
   4  * @file
   5  */
   6
   7 if ( !defined( 'MEDIAWIKI' ) ) {
   8         die( "This file is part of MediaWiki, it is not a valid entry point" );
   9 }
  10
  11 // Hide compatibility functions from Doxygen
  12 /// @cond
  13
  14 /**
  15  * Compatibility functions
  16  *
  17  * We support PHP 5.2.3 and up.
  18  * Re-implementations of newer functions or functions in non-standard
  19  * PHP extensions may be included here.
  20  */
  21
  22 if( !function_exists( 'iconv' ) ) {
  23         /** @codeCoverageIgnore */
  24         function iconv( $from, $to, $string ) {
  25                 return Fallback::iconv( $from, $to, $string );
  26         }
  27 }
  28
  29 if ( !function_exists( 'mb_substr' ) ) {
  30         /** @codeCoverageIgnore */
  31         function mb_substr( $str, $start, $count='end' ) {
  32                 return Fallback::mb_substr( $str, $start, $count );
  33         }
  34
  35         /** @codeCoverageIgnore */
  36         function mb_substr_split_unicode( $str, $splitPos ) {
  37                 return Fallback::mb_substr_split_unicode( $str, $splitPos );
  38         }
  39 }
  40
  41 if ( !function_exists( 'mb_strlen' ) ) {
  42         /** @codeCoverageIgnore */
  43         function mb_strlen( $str, $enc = '' ) {
  44                 return Fallback::mb_strlen( $str, $enc );
  45         }
  46 }
  47
  48 if( !function_exists( 'mb_strpos' ) ) {
  49         /** @codeCoverageIgnore */
  50         function mb_strpos( $haystack, $needle, $offset = 0, $encoding = '' ) {
  51                 return Fallback::mb_strpos( $haystack, $needle, $offset, $encoding );
  52         }
  53
  54 }
  55
  56 if( !function_exists( 'mb_strrpos' ) ) {
  57         /** @codeCoverageIgnore */
  58         function mb_strrpos( $haystack, $needle, $offset = 0, $encoding = '' ) {
  59                 return Fallback::mb_strrpos( $haystack, $needle, $offset, $encoding );
  60         }
  61 }
  62
  63
  64 // Support for Wietse Venema's taint feature
  65 if ( !function_exists( 'istainted' ) ) {
  66         /** @codeCoverageIgnore */
  67         function istainted( $var ) {
  68                 return 0;
  69         }
  70         /** @codeCoverageIgnore */
  71         function taint( $var, $level = 0 ) {}
  72         /** @codeCoverageIgnore */
  73         function untaint( $var, $level = 0 ) {}
  74         define( 'TC_HTML', 1 );
  75         define( 'TC_SHELL', 1 );
  76         define( 'TC_MYSQL', 1 );
  77         define( 'TC_PCRE', 1 );
  78         define( 'TC_SELF', 1 );
  79 }
  80 /// @endcond
  81
  82 /**
  83  * Like array_diff( $a, $b ) except that it works with two-dimensional arrays.
  84  */
  85 function wfArrayDiff2( $a, $b ) {
  86         return array_udiff( $a, $b, 'wfArrayDiff2_cmp' );
  87 }
  88
  89 /**
  90  * @param $a
  91  * @param $b
  92  * @return int
  93  */
  94 function wfArrayDiff2_cmp( $a, $b ) {
  95         if ( !is_array( $a ) ) {
  96                 return strcmp( $a, $b );
  97         } elseif ( count( $a ) !== count( $b ) ) {
  98                 return count( $a ) < count( $b ) ? -1 : 1;
  99         } else {
 100                 reset( $a );
 101                 reset( $b );
 102                 while( ( list( , $valueA ) = each( $a ) ) && ( list( , $valueB ) = each( $b ) ) ) {
 103                         $cmp = strcmp( $valueA, $valueB );
 104                         if ( $cmp !== 0 ) {
 105                                 return $cmp;
 106                         }
 107                 }
 108                 return 0;
 109         }
 110 }
 111
 112 /**
 113  * Array lookup
 114  * Returns an array where the values in the first array are replaced by the
 115  * values in the second array with the corresponding keys
 116  *
 117  * @param $a Array
 118  * @param $b Array
 119  * @return array
 120  */
 121 function wfArrayLookup( $a, $b ) {
 122         return array_flip( array_intersect( array_flip( $a ), array_keys( $b ) ) );
 123 }
 124
 125 /**
 126  * Appends to second array if $value differs from that in $default
 127  *
 128  * @param $key String|Int
 129  * @param $value Mixed
 130  * @param $default Mixed
 131  * @param $changed Array to alter
 132  */
 133 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
 134         if ( is_null( $changed ) ) {
 135                 throw new MWException( 'GlobalFunctions::wfAppendToArrayIfNotDefault got null' );
 136         }
 137         if ( $default[$key] !== $value ) {
 138                 $changed[$key] = $value;
 139         }
 140 }
 141
 142 /**
 143  * Backwards array plus for people who haven't bothered to read the PHP manual
 144  * XXX: will not darn your socks for you.
 145  *
 146  * @param $array1 Array
 147  * @param [$array2, [...]] Arrays
 148  * @return Array
 149  */
 150 function wfArrayMerge( $array1/* ... */ ) {
 151         $args = func_get_args();
 152         $args = array_reverse( $args, true );
 153         $out = array();
 154         foreach ( $args as $arg ) {
 155                 $out += $arg;
 156         }
 157         return $out;
 158 }
 159
 160 /**
 161  * Merge arrays in the style of getUserPermissionsErrors, with duplicate removal
 162  * e.g.
 163  *      wfMergeErrorArrays(
 164  *              array( array( 'x' ) ),
 165  *              array( array( 'x', '2' ) ),
 166  *              array( array( 'x' ) ),
 167  *              array( array( 'y') )
 168  *      );
 169  * returns:
 170  *              array(
 171  *              array( 'x', '2' ),
 172  *              array( 'x' ),
 173  *              array( 'y' )
 174  *      )
 175  * @param varargs
 176  * @return Array
 177  */
 178 function wfMergeErrorArrays( /*...*/ ) {
 179         $args = func_get_args();
 180         $out = array();
 181         foreach ( $args as $errors ) {
 182                 foreach ( $errors as $params ) {
 183                         # @todo FIXME: Sometimes get nested arrays for $params,
 184                         # which leads to E_NOTICEs
 185                         $spec = implode( "\t", $params );
 186                         $out[$spec] = $params;
 187                 }
 188         }
 189         return array_values( $out );
 190 }
 191
 192 /**
 193  * Insert array into another array after the specified *KEY*
 194  *
 195  * @param $array Array: The array.
 196  * @param $insert Array: The array to insert.
 197  * @param $after Mixed: The key to insert after
 198  * @return Array
 199  */
 200 function wfArrayInsertAfter( $array, $insert, $after ) {
 201         // Find the offset of the element to insert after.
 202         $keys = array_keys( $array );
 203         $offsetByKey = array_flip( $keys );
 204
 205         $offset = $offsetByKey[$after];
 206
 207         // Insert at the specified offset
 208         $before = array_slice( $array, 0, $offset + 1, true );
 209         $after = array_slice( $array, $offset + 1, count( $array ) - $offset, true );
 210
 211         $output = $before + $insert + $after;
 212
 213         return $output;
 214 }
 215
 216 /**
 217  * Recursively converts the parameter (an object) to an array with the same data
 218  *
 219  * @param $objOrArray Object|Array
 220  * @param $recursive Bool
 221  * @return Array
 222  */
 223 function wfObjectToArray( $objOrArray, $recursive = true ) {
 224         $array = array();
 225         if( is_object( $objOrArray ) ) {
 226                 $objOrArray = get_object_vars( $objOrArray );
 227         }
 228         foreach ( $objOrArray as $key => $value ) {
 229                 if ( $recursive && ( is_object( $value ) || is_array( $value ) ) ) {
 230                         $value = wfObjectToArray( $value );
 231                 }
 232
 233                 $array[$key] = $value;
 234         }
 235
 236         return $array;
 237 }
 238
 239 /**
 240  * Wrapper around array_map() which also taints variables
 241  *
 242  * @param  $function Callback
 243  * @param  $input Array
 244  * @return Array
 245  */
 246 function wfArrayMap( $function, $input ) {
 247         $ret = array_map( $function, $input );
 248         foreach ( $ret as $key => $value ) {
 249                 $taint = istainted( $input[$key] );
 250                 if ( $taint ) {
 251                         taint( $ret[$key], $taint );
 252                 }
 253         }
 254         return $ret;
 255 }
 256
 257 /**
 258  * Get a random decimal value between 0 and 1, in a way
 259  * not likely to give duplicate values for any realistic
 260  * number of articles.
 261  *
 262  * @return string
 263  */
 264 function wfRandom() {
 265         # The maximum random value is "only" 2^31-1, so get two random
 266         # values to reduce the chance of dupes
 267         $max = mt_getrandmax() + 1;
 268         $rand = number_format( ( mt_rand() * $max + mt_rand() )
 269                 / $max / $max, 12, '.', '' );
 270         return $rand;
 271 }
 272
 273 /**
 274  * We want some things to be included as literal characters in our title URLs
 275  * for prettiness, which urlencode encodes by default.  According to RFC 1738,
 276  * all of the following should be safe:
 277  *
 278  * ;:@&=$-_.+!*'(),
 279  *
 280  * But + is not safe because it's used to indicate a space; &= are only safe in
 281  * paths and not in queries (and we don't distinguish here); ' seems kind of
 282  * scary; and urlencode() doesn't touch -_. to begin with.  Plus, although /
 283  * is reserved, we don't care.  So the list we unescape is:
 284  *
 285  * ;:@$!*(),/
 286  *
 287  * However, IIS7 redirects fail when the url contains a colon (Bug 22709),
 288  * so no fancy : for IIS7.
 289  *
 290  * %2F in the page titles seems to fatally break for some reason.
 291  *
 292  * @param $s String:
 293  * @return string
 294 */
 295 function wfUrlencode( $s ) {
 296         static $needle;
 297         if ( is_null( $s ) ) {
 298                 $needle = null;
 299                 return;
 300         }
 301
 302         if ( is_null( $needle ) ) {
 303                 $needle = array( '%3B', '%40', '%24', '%21', '%2A', '%28', '%29', '%2C', '%2F' );
 304                 if ( !isset( $_SERVER['SERVER_SOFTWARE'] ) || ( strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/7' ) === false ) ) {
 305                         $needle[] = '%3A';
 306                 }
 307         }
 308
 309         $s = urlencode( $s );
 310         $s = str_ireplace(
 311                 $needle,
 312                 array( ';', '@', '$', '!', '*', '(', ')', ',', '/', ':' ),
 313                 $s
 314         );
 315
 316         return $s;
 317 }
 318
 319 /**
 320  * This function takes two arrays as input, and returns a CGI-style string, e.g.
 321  * "days=7&limit=100". Options in the first array override options in the second.
 322  * Options set to "" will not be output.
 323  *
 324  * @param $array1 Array ( String|Array )
 325  * @param $array2 Array ( String|Array )
 326  * @param $prefix String
 327  * @return String
 328  */
 329 function wfArrayToCGI( $array1, $array2 = null, $prefix = '' ) {
 330         if ( !is_null( $array2 ) ) {
 331                 $array1 = $array1 + $array2;
 332         }
 333
 334         $cgi = '';
 335         foreach ( $array1 as $key => $value ) {
 336                 if ( $value !== '' ) {
 337                         if ( $cgi != '' ) {
 338                                 $cgi .= '&';
 339                         }
 340                         if ( $prefix !== '' ) {
 341                                 $key = $prefix . "[$key]";
 342                         }
 343                         if ( is_array( $value ) ) {
 344                                 $firstTime = true;
 345                                 foreach ( $value as $k => $v ) {
 346                                         $cgi .= $firstTime ? '' : '&';
 347                                         if ( is_array( $v ) ) {
 348                                                 $cgi .= wfArrayToCGI( $v, null, $key . "[$k]" );
 349                                         } else {
 350                                                 $cgi .= urlencode( $key . "[$k]" ) . '=' . urlencode( $v );
 351                                         }
 352                                         $firstTime = false;
 353                                 }
 354                         } else {
 355                                 if ( is_object( $value ) ) {
 356                                         $value = $value->__toString();
 357                                 }
 358                                 $cgi .= urlencode( $key ) . '=' . urlencode( $value );
 359                         }
 360                 }
 361         }
 362         return $cgi;
 363 }
 364
 365 /**
 366  * This is the logical opposite of wfArrayToCGI(): it accepts a query string as
 367  * its argument and returns the same string in array form.  This allows compa-
 368  * tibility with legacy functions that accept raw query strings instead of nice
 369  * arrays.  Of course, keys and values are urldecode()d.  Don't try passing in-
 370  * valid query strings, or it will explode.
 371  *
 372  * @param $query String: query string
 373  * @return array Array version of input
 374  */
 375 function wfCgiToArray( $query ) {
 376         if ( isset( $query[0] ) && $query[0] == '?' ) {
 377                 $query = substr( $query, 1 );
 378         }
 379         $bits = explode( '&', $query );
 380         $ret = array();
 381         foreach ( $bits as $bit ) {
 382                 if ( $bit === '' ) {
 383                         continue;
 384                 }
 385                 list( $key, $value ) = explode( '=', $bit );
 386                 $key = urldecode( $key );
 387                 $value = urldecode( $value );
 388                 if ( strpos( $key, '[' ) !== false ) {
 389                         $keys = array_reverse( explode( '[', $key ) );
 390                         $key = array_pop( $keys );
 391                         $temp = $value;
 392                         foreach ( $keys as $k ) {
 393                                 $k = substr( $k, 0, -1 );
 394                                 $temp = array( $k => $temp );
 395                         }
 396                         if ( isset( $ret[$key] ) ) {
 397                                 $ret[$key] = array_merge( $ret[$key], $temp );
 398                         } else {
 399                                 $ret[$key] = $temp;
 400                         }
 401                 } else {
 402                         $ret[$key] = $value;
 403                 }
 404         }
 405         return $ret;
 406 }
 407
 408 /**
 409  * Append a query string to an existing URL, which may or may not already
 410  * have query string parameters already. If so, they will be combined.
 411  *
 412  * @param $url String
 413  * @param $query Mixed: string or associative array
 414  * @return string
 415  */
 416 function wfAppendQuery( $url, $query ) {
 417         if ( is_array( $query ) ) {
 418                 $query = wfArrayToCGI( $query );
 419         }
 420         if( $query != '' ) {
 421                 if( false === strpos( $url, '?' ) ) {
 422                         $url .= '?';
 423                 } else {
 424                         $url .= '&';
 425                 }
 426                 $url .= $query;
 427         }
 428         return $url;
 429 }
 430
 431 /**
 432  * Expand a potentially local URL to a fully-qualified URL.  Assumes $wgServer
 433  * is correct.
 434  *
 435  * The meaning of the PROTO_* constants is as follows:
 436  * PROTO_HTTP: Output a URL starting with http://
 437  * PROTO_HTTPS: Output a URL starting with https://
 438  * PROTO_RELATIVE: Output a URL starting with // (protocol-relative URL)
 439  * PROTO_CURRENT: Output a URL starting with either http:// or https:// , depending on which protocol was used for the current incoming request
 440  *
 441  * @todo this won't work with current-path-relative URLs
 442  * like "subdir/foo.html", etc.
 443  *
 444  * @param $url String: either fully-qualified or a local path + query
 445  * @param $defaultProto Mixed: one of the PROTO_* constants. Determines the protocol to use if $url or $wgServer is protocol-relative
 446  * @return string Fully-qualified URL
 447  */
 448 function wfExpandUrl( $url, $defaultProto = PROTO_CURRENT ) {
 449         global $wgServer;
 450         if ( $defaultProto === PROTO_CURRENT ) {
 451                 $defaultProto = WebRequest::detectProtocol() . '://';
 452         }
 453
 454         // Analyze $wgServer to obtain its protocol
 455         $bits = wfParseUrl( $wgServer );
 456         $serverHasProto = $bits && $bits['scheme'] != '';
 457         $defaultProtoWithoutSlashes = substr( $defaultProto, 0, -2 );
 458
 459         if( substr( $url, 0, 2 ) == '//' ) {
 460                 return $defaultProtoWithoutSlashes . $url;
 461         } elseif( substr( $url, 0, 1 ) == '/' ) {
 462                 // If $wgServer is protocol-relative, prepend $defaultProtoWithoutSlashes, otherwise leave it alone
 463                 return ( $serverHasProto ? '' : $defaultProtoWithoutSlashes ) . $wgServer . $url;
 464         } else {
 465                 return $url;
 466         }
 467 }
 468
 469 /**
 470  * Returns a regular expression of url protocols
 471  *
 472  * @param $includeProtocolRelative bool If false, remove '//' from the returned protocol list.
 473  *        DO NOT USE this directy, use wfUrlProtocolsWithoutProtRel() instead
 474  * @return String
 475  */
 476 function wfUrlProtocols( $includeProtocolRelative = true ) {
 477         global $wgUrlProtocols;
 478
 479         // Cache return values separately based on $includeProtocolRelative
 480         static $withProtRel = null, $withoutProtRel = null;
 481         $cachedValue = $includeProtocolRelative ? $withProtRel : $withoutProtRel;
 482         if ( !is_null( $cachedValue ) ) {
 483                 return $cachedValue;
 484         }
 485
 486         // Support old-style $wgUrlProtocols strings, for backwards compatibility
 487         // with LocalSettings files from 1.5
 488         if ( is_array( $wgUrlProtocols ) ) {
 489                 $protocols = array();
 490                 foreach ( $wgUrlProtocols as $protocol ) {
 491                         // Filter out '//' if !$includeProtocolRelative
 492                         if ( $includeProtocolRelative || $protocol !== '//' ) {
 493                                 $protocols[] = preg_quote( $protocol, '/' );
 494                         }
 495                 }
 496
 497                 $retval = implode( '|', $protocols );
 498         } else {
 499                 // Ignore $includeProtocolRelative in this case
 500                 // This case exists for pre-1.6 compatibility, and we can safely assume
 501                 // that '//' won't appear in a pre-1.6 config because protocol-relative
 502                 // URLs weren't supported until 1.18
 503                 $retval = $wgUrlProtocols;
 504         }
 505
 506         // Cache return value
 507         if ( $includeProtocolRelative ) {
 508                 $withProtRel = $retval;
 509         } else {
 510                 $withoutProtRel = $retval;
 511         }
 512         return $retval;
 513 }
 514
 515 /**
 516  * Like wfUrlProtocols(), but excludes '//' from the protocol list. Use this if
 517  * you need a regex that matches all URL protocols but does not match protocol-
 518  * relative URLs
 519  */
 520 function wfUrlProtocolsWithoutProtRel() {
 521         return wfUrlProtocols( false );
 522 }
 523
 524 /**
 525  * parse_url() work-alike, but non-broken.  Differences:
 526  *
 527  * 1) Does not raise warnings on bad URLs (just returns false)
 528  * 2) Handles protocols that don't use :// (e.g., mailto: and news: , as well as protocol-relative URLs) correctly
 529  * 3) Adds a "delimiter" element to the array, either '://', ':' or '//' (see (2))
 530  *
 531  * @param $url String: a URL to parse
 532  * @return Array: bits of the URL in an associative array, per PHP docs
 533  */
 534 function wfParseUrl( $url ) {
 535         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
 536
 537         // Protocol-relative URLs are handled really badly by parse_url(). It's so bad that the easiest
 538         // way to handle them is to just prepend 'http:' and strip the protocol out later
 539         $wasRelative = substr( $url, 0, 2 ) == '//';
 540         if ( $wasRelative ) {
 541                 $url = "http:$url";
 542         }
 543         wfSuppressWarnings();
 544         $bits = parse_url( $url );
 545         wfRestoreWarnings();
 546         // parse_url() returns an array without scheme for some invalid URLs, e.g.
 547         // parse_url("%0Ahttp://example.com") == array( 'host' => '%0Ahttp', 'path' => 'example.com' )
 548         if ( !$bits || !isset( $bits['scheme'] ) ) {
 549                 return false;
 550         }
 551
 552         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
 553         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
 554                 $bits['delimiter'] = '://';
 555         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
 556                 $bits['delimiter'] = ':';
 557                 // parse_url detects for news: and mailto: the host part of an url as path
 558                 // We have to correct this wrong detection
 559                 if ( isset( $bits['path'] ) ) {
 560                         $bits['host'] = $bits['path'];
 561                         $bits['path'] = '';
 562                 }
 563         } else {
 564                 return false;
 565         }
 566
 567         /* Provide an empty host for eg. file:/// urls (see bug 28627) */
 568         if ( !isset( $bits['host'] ) ) {
 569                 $bits['host'] = '';
 570
 571                 /* parse_url loses the third / for file:///c:/ urls (but not on variants) */
 572                 if ( substr( $bits['path'], 0, 1 ) !== '/' ) {
 573                         $bits['path'] = '/' . $bits['path'];
 574                 }
 575         }
 576
 577         // If the URL was protocol-relative, fix scheme and delimiter
 578         if ( $wasRelative ) {
 579                 $bits['scheme'] = '';
 580                 $bits['delimiter'] = '//';
 581         }
 582         return $bits;
 583 }
 584
 585 /**
 586  * Make a URL index, appropriate for the el_index field of externallinks.
 587  *
 588  * @param $url String
 589  * @return String
 590  */
 591 function wfMakeUrlIndex( $url ) {
 592         $bits = wfParseUrl( $url );
 593
 594         // Reverse the labels in the hostname, convert to lower case
 595         // For emails reverse domainpart only
 596         if ( $bits['scheme'] == 'mailto' ) {
 597                 $mailparts = explode( '@', $bits['host'], 2 );
 598                 if ( count( $mailparts ) === 2 ) {
 599                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
 600                 } else {
 601                         // No domain specified, don't mangle it
 602                         $domainpart = '';
 603                 }
 604                 $reversedHost = $domainpart . '@' . $mailparts[0];
 605         } else {
 606                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
 607         }
 608         // Add an extra dot to the end
 609         // Why? Is it in wrong place in mailto links?
 610         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
 611                 $reversedHost .= '.';
 612         }
 613         // Reconstruct the pseudo-URL
 614         $prot = $bits['scheme'];
 615         $index = $prot . $bits['delimiter'] . $reversedHost;
 616         // Leave out user and password. Add the port, path, query and fragment
 617         if ( isset( $bits['port'] ) ) {
 618                 $index .= ':' . $bits['port'];
 619         }
 620         if ( isset( $bits['path'] ) ) {
 621                 $index .= $bits['path'];
 622         } else {
 623                 $index .= '/';
 624         }
 625         if ( isset( $bits['query'] ) ) {
 626                 $index .= '?' . $bits['query'];
 627         }
 628         if ( isset( $bits['fragment'] ) ) {
 629                 $index .= '#' . $bits['fragment'];
 630         }
 631         return $index;
 632 }
 633
 634 /**
 635  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
 636  * In normal operation this is a NOP.
 637  *
 638  * Controlling globals:
 639  * $wgDebugLogFile - points to the log file
 640  * $wgProfileOnly - if set, normal debug messages will not be recorded.
 641  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
 642  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
 643  *
 644  * @param $text String
 645  * @param $logonly Bool: set true to avoid appearing in HTML when $wgDebugComments is set
 646  */
 647 function wfDebug( $text, $logonly = false ) {
 648         global $wgOut, $wgDebugLogFile, $wgDebugComments, $wgProfileOnly, $wgDebugRawPage;
 649         global $wgDebugLogPrefix, $wgShowDebug;
 650
 651         static $cache = array(); // Cache of unoutputted messages
 652         $text = wfDebugTimer() . $text;
 653
 654         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
 655                 return;
 656         }
 657
 658         if ( ( $wgDebugComments || $wgShowDebug ) && !$logonly ) {
 659                 $cache[] = $text;
 660
 661                 if ( isset( $wgOut ) && is_object( $wgOut ) ) {
 662                         // add the message and any cached messages to the output
 663                         array_map( array( $wgOut, 'debug' ), $cache );
 664                         $cache = array();
 665                 }
 666         }
 667         if ( wfRunHooks( 'Debug', array( $text, null /* no log group */ ) ) ) {
 668                 if ( $wgDebugLogFile != '' && !$wgProfileOnly ) {
 669                         # Strip unprintables; they can switch terminal modes when binary data
 670                         # gets dumped, which is pretty annoying.
 671                         $text = preg_replace( '![\x00-\x08\x0b\x0c\x0e-\x1f]!', ' ', $text );
 672                         $text = $wgDebugLogPrefix . $text;
 673                         wfErrorLog( $text, $wgDebugLogFile );
 674                 }
 675         }
 676 }
 677
 678 /**
 679  * Returns true if debug logging should be suppressed if $wgDebugRawPage = false
 680  */
 681 function wfIsDebugRawPage() {
 682         static $cache;
 683         if ( $cache !== null ) {
 684                 return $cache;
 685         }
 686         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
 687         if ( ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' )
 688                 || (
 689                         isset( $_SERVER['SCRIPT_NAME'] )
 690                         && substr( $_SERVER['SCRIPT_NAME'], -8 ) == 'load.php'
 691                 ) )
 692         {
 693                 $cache = true;
 694         } else {
 695                 $cache = false;
 696         }
 697         return $cache;
 698 }
 699
 700 /**
 701  * Get microsecond timestamps for debug logs
 702  *
 703  * @return string
 704  */
 705 function wfDebugTimer() {
 706         global $wgDebugTimestamps;
 707         if ( !$wgDebugTimestamps ) {
 708                 return '';
 709         }
 710         static $start = null;
 711
 712         if ( $start === null ) {
 713                 $start = microtime( true );
 714                 $prefix = "\n$start";
 715         } else {
 716                 $prefix = sprintf( "%6.4f", microtime( true ) - $start );
 717         }
 718
 719         return $prefix . '  ';
 720 }
 721
 722 /**
 723  * Send a line giving PHP memory usage.
 724  *
 725  * @param $exact Bool: print exact values instead of kilobytes (default: false)
 726  */
 727 function wfDebugMem( $exact = false ) {
 728         $mem = memory_get_usage();
 729         if( !$exact ) {
 730                 $mem = floor( $mem / 1024 ) . ' kilobytes';
 731         } else {
 732                 $mem .= ' bytes';
 733         }
 734         wfDebug( "Memory usage: $mem\n" );
 735 }
 736
 737 /**
 738  * Send a line to a supplementary debug log file, if configured, or main debug log if not.
 739  * $wgDebugLogGroups[$logGroup] should be set to a filename to send to a separate log.
 740  *
 741  * @param $logGroup String
 742  * @param $text String
 743  * @param $public Bool: whether to log the event in the public log if no private
 744  *                     log file is specified, (default true)
 745  */
 746 function wfDebugLog( $logGroup, $text, $public = true ) {
 747         global $wgDebugLogGroups, $wgShowHostnames;
 748         $text = trim( $text ) . "\n";
 749         if( isset( $wgDebugLogGroups[$logGroup] ) ) {
 750                 $time = wfTimestamp( TS_DB );
 751                 $wiki = wfWikiID();
 752                 if ( $wgShowHostnames ) {
 753                         $host = wfHostname();
 754                 } else {
 755                         $host = '';
 756                 }
 757                 if ( wfRunHooks( 'Debug', array( $text, $logGroup ) ) ) {
 758                         wfErrorLog( "$time $host $wiki: $text", $wgDebugLogGroups[$logGroup] );
 759                 }
 760         } elseif ( $public === true ) {
 761                 wfDebug( $text, true );
 762         }
 763 }
 764
 765 /**
 766  * Log for database errors
 767  *
 768  * @param $text String: database error message.
 769  */
 770 function wfLogDBError( $text ) {
 771         global $wgDBerrorLog, $wgDBname;
 772         if ( $wgDBerrorLog ) {
 773                 $host = trim(`hostname`);
 774                 $text = date( 'D M j G:i:s T Y' ) . "\t$host\t$wgDBname\t$text";
 775                 wfErrorLog( $text, $wgDBerrorLog );
 776         }
 777 }
 778
 779 /**
 780  * Log to a file without getting "file size exceeded" signals.
 781  *
 782  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
 783  * send lines to the specified port, prefixed by the specified prefix and a space.
 784  *
 785  * @param $text String
 786  * @param $file String filename
 787  */
 788 function wfErrorLog( $text, $file ) {
 789         if ( substr( $file, 0, 4 ) == 'udp:' ) {
 790                 # Needs the sockets extension
 791                 if ( preg_match( '!^(tcp|udp):(?://)?\[([0-9a-fA-F:]+)\]:(\d+)(?:/(.*))?$!', $file, $m ) ) {
 792                         // IPv6 bracketed host
 793                         $host = $m[2];
 794                         $port = intval( $m[3] );
 795                         $prefix = isset( $m[4] ) ? $m[4] : false;
 796                         $domain = AF_INET6;
 797                 } elseif ( preg_match( '!^(tcp|udp):(?://)?([a-zA-Z0-9.-]+):(\d+)(?:/(.*))?$!', $file, $m ) ) {
 798                         $host = $m[2];
 799                         if ( !IP::isIPv4( $host ) ) {
 800                                 $host = gethostbyname( $host );
 801                         }
 802                         $port = intval( $m[3] );
 803                         $prefix = isset( $m[4] ) ? $m[4] : false;
 804                         $domain = AF_INET;
 805                 } else {
 806                         throw new MWException( __METHOD__ . ': Invalid UDP specification' );
 807                 }
 808
 809                 // Clean it up for the multiplexer
 810                 if ( strval( $prefix ) !== '' ) {
 811                         $text = preg_replace( '/^/m', $prefix . ' ', $text );
 812
 813                         // Limit to 64KB
 814                         if ( strlen( $text ) > 65534 ) {
 815                                 $text = substr( $text, 0, 65534 );
 816                         }
 817
 818                         if ( substr( $text, -1 ) != "\n" ) {
 819                                 $text .= "\n";
 820                         }
 821                 } elseif ( strlen( $text ) > 65535 ) {
 822                         $text = substr( $text, 0, 65535 );
 823                 }
 824
 825                 $sock = socket_create( $domain, SOCK_DGRAM, SOL_UDP );
 826                 if ( !$sock ) {
 827                         return;
 828                 }
 829                 socket_sendto( $sock, $text, strlen( $text ), 0, $host, $port );
 830                 socket_close( $sock );
 831         } else {
 832                 wfSuppressWarnings();
 833                 $exists = file_exists( $file );
 834                 $size = $exists ? filesize( $file ) : false;
 835                 if ( !$exists || ( $size !== false && $size + strlen( $text ) < 0x7fffffff ) ) {
 836                         file_put_contents( $file, $text, FILE_APPEND );
 837                 }
 838                 wfRestoreWarnings();
 839         }
 840 }
 841
 842 /**
 843  * @todo document
 844  */
 845 function wfLogProfilingData() {
 846         global $wgRequestTime, $wgDebugLogFile, $wgDebugRawPage, $wgRequest;
 847         global $wgProfileLimit, $wgUser;
 848
 849         $profiler = Profiler::instance();
 850
 851         # Profiling must actually be enabled...
 852         if ( $profiler->isStub() ) {
 853                 return;
 854         }
 855
 856         // Get total page request time and only show pages that longer than
 857         // $wgProfileLimit time (default is 0)
 858         $now = wfTime();
 859         $elapsed = $now - $wgRequestTime;
 860         if ( $elapsed <= $wgProfileLimit ) {
 861                 return;
 862         }
 863
 864         $profiler->logData();
 865
 866         // Check whether this should be logged in the debug file.
 867         if ( $wgDebugLogFile == '' || ( !$wgDebugRawPage && wfIsDebugRawPage() ) ) {
 868                 return;
 869         }
 870
 871         $forward = '';
 872         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
 873                 $forward = ' forwarded for ' . $_SERVER['HTTP_X_FORWARDED_FOR'];
 874         }
 875         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
 876                 $forward .= ' client IP ' . $_SERVER['HTTP_CLIENT_IP'];
 877         }
 878         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
 879                 $forward .= ' from ' . $_SERVER['HTTP_FROM'];
 880         }
 881         if ( $forward ) {
 882                 $forward = "\t(proxied via {$_SERVER['REMOTE_ADDR']}{$forward})";
 883         }
 884         // Don't load $wgUser at this late stage just for statistics purposes
 885         // @todo FIXME: We can detect some anons even if it is not loaded. See User::getId()
 886         if ( $wgUser->isItemLoaded( 'id' ) && $wgUser->isAnon() ) {
 887                 $forward .= ' anon';
 888         }
 889         $log = sprintf( "%s\t%04.3f\t%s\n",
 890                 gmdate( 'YmdHis' ), $elapsed,
 891                 urldecode( $wgRequest->getRequestURL() . $forward ) );
 892
 893         wfErrorLog( $log . $profiler->getOutput(), $wgDebugLogFile );
 894 }
 895
 896 /**
 897  * Check if the wiki read-only lock file is present. This can be used to lock
 898  * off editing functions, but doesn't guarantee that the database will not be
 899  * modified.
 900  *
 901  * @return bool
 902  */
 903 function wfReadOnly() {
 904         global $wgReadOnlyFile, $wgReadOnly;
 905
 906         if ( !is_null( $wgReadOnly ) ) {
 907                 return (bool)$wgReadOnly;
 908         }
 909         if ( $wgReadOnlyFile == '' ) {
 910                 return false;
 911         }
 912         // Set $wgReadOnly for faster access next time
 913         if ( is_file( $wgReadOnlyFile ) ) {
 914                 $wgReadOnly = file_get_contents( $wgReadOnlyFile );
 915         } else {
 916                 $wgReadOnly = false;
 917         }
 918         return (bool)$wgReadOnly;
 919 }
 920
 921 function wfReadOnlyReason() {
 922         global $wgReadOnly;
 923         wfReadOnly();
 924         return $wgReadOnly;
 925 }
 926
 927 /**
 928  * Return a Language object from $langcode
 929  *
 930  * @param $langcode Mixed: either:
 931  *                  - a Language object
 932  *                  - code of the language to get the message for, if it is
 933  *                    a valid code create a language for that language, if
 934  *                    it is a string but not a valid code then make a basic
 935  *                    language object
 936  *                  - a boolean: if it's false then use the current users
 937  *                    language (as a fallback for the old parameter
 938  *                    functionality), or if it is true then use the wikis
 939  * @return Language object
 940  */
 941 function wfGetLangObj( $langcode = false ) {
 942         # Identify which language to get or create a language object for.
 943         # Using is_object here due to Stub objects.
 944         if( is_object( $langcode ) ) {
 945                 # Great, we already have the object (hopefully)!
 946                 return $langcode;
 947         }
 948
 949         global $wgContLang, $wgLanguageCode;
 950         if( $langcode === true || $langcode === $wgLanguageCode ) {
 951                 # $langcode is the language code of the wikis content language object.
 952                 # or it is a boolean and value is true
 953                 return $wgContLang;
 954         }
 955
 956         global $wgLang;
 957         if( $langcode === false || $langcode === $wgLang->getCode() ) {
 958                 # $langcode is the language code of user language object.
 959                 # or it was a boolean and value is false
 960                 return $wgLang;
 961         }
 962
 963         $validCodes = array_keys( Language::getLanguageNames() );
 964         if( in_array( $langcode, $validCodes ) ) {
 965                 # $langcode corresponds to a valid language.
 966                 return Language::factory( $langcode );
 967         }
 968
 969         # $langcode is a string, but not a valid language code; use content language.
 970         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
 971         return $wgContLang;
 972 }
 973
 974 /**
 975  * Old function when $wgBetterDirectionality existed
 976  * Removed in core, kept in extensions for backwards compat.
 977  *
 978  * @deprecated since 1.18
 979  * @return Language
 980  */
 981 function wfUILang() {
 982         global $wgLang;
 983         return $wgLang;
 984 }
 985
 986 /**
 987  * This is the new function for getting translated interface messages.
 988  * See the Message class for documentation how to use them.
 989  * The intention is that this function replaces all old wfMsg* functions.
 990  * @param $key \string Message key.
 991  * Varargs: normal message parameters.
 992  * @return Message
 993  * @since 1.17
 994  */
 995 function wfMessage( $key /*...*/) {
 996         $params = func_get_args();
 997         array_shift( $params );
 998         if ( isset( $params[0] ) && is_array( $params[0] ) ) {
 999                 $params = $params[0];
1000         }
1001         return new Message( $key, $params );
1002 }
1003
1004 /**
1005  * This function accepts multiple message keys and returns a message instance
1006  * for the first message which is non-empty. If all messages are empty then an
1007  * instance of the first message key is returned.
1008  * @param varargs: message keys
1009  * @return Message
1010  * @since 1.18
1011  */
1012 function wfMessageFallback( /*...*/ ) {
1013         $args = func_get_args();
1014         return MWFunction::callArray( 'Message::newFallbackSequence', $args );
1015 }
1016
1017 /**
1018  * Get a message from anywhere, for the current user language.
1019  *
1020  * Use wfMsgForContent() instead if the message should NOT
1021  * change depending on the user preferences.
1022  *
1023  * @param $key String: lookup key for the message, usually
1024  *    defined in languages/Language.php
1025  *
1026  * Parameters to the message, which can be used to insert variable text into
1027  * it, can be passed to this function in the following formats:
1028  * - One per argument, starting at the second parameter
1029  * - As an array in the second parameter
1030  * These are not shown in the function definition.
1031  *
1032  * @return String
1033  */
1034 function wfMsg( $key ) {
1035         $args = func_get_args();
1036         array_shift( $args );
1037         return wfMsgReal( $key, $args );
1038 }
1039
1040 /**
1041  * Same as above except doesn't transform the message
1042  *
1043  * @param $key String
1044  * @return String
1045  */
1046 function wfMsgNoTrans( $key ) {
1047         $args = func_get_args();
1048         array_shift( $args );
1049         return wfMsgReal( $key, $args, true, false, false );
1050 }
1051
1052 /**
1053  * Get a message from anywhere, for the current global language
1054  * set with $wgLanguageCode.
1055  *
1056  * Use this if the message should NOT change dependent on the
1057  * language set in the user's preferences. This is the case for
1058  * most text written into logs, as well as link targets (such as
1059  * the name of the copyright policy page). Link titles, on the
1060  * other hand, should be shown in the UI language.
1061  *
1062  * Note that MediaWiki allows users to change the user interface
1063  * language in their preferences, but a single installation
1064  * typically only contains content in one language.
1065  *
1066  * Be wary of this distinction: If you use wfMsg() where you should
1067  * use wfMsgForContent(), a user of the software may have to
1068  * customize potentially hundreds of messages in
1069  * order to, e.g., fix a link in every possible language.
1070  *
1071  * @param $key String: lookup key for the message, usually
1072  *     defined in languages/Language.php
1073  * @return String
1074  */
1075 function wfMsgForContent( $key ) {
1076         global $wgForceUIMsgAsContentMsg;
1077         $args = func_get_args();
1078         array_shift( $args );
1079         $forcontent = true;
1080         if( is_array( $wgForceUIMsgAsContentMsg ) &&
1081                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
1082         {
1083                 $forcontent = false;
1084         }
1085         return wfMsgReal( $key, $args, true, $forcontent );
1086 }
1087
1088 /**
1089  * Same as above except doesn't transform the message
1090  *
1091  * @param $key String
1092  * @return String
1093  */
1094 function wfMsgForContentNoTrans( $key ) {
1095         global $wgForceUIMsgAsContentMsg;
1096         $args = func_get_args();
1097         array_shift( $args );
1098         $forcontent = true;
1099         if( is_array( $wgForceUIMsgAsContentMsg ) &&
1100                 in_array( $key, $wgForceUIMsgAsContentMsg ) )
1101         {
1102                 $forcontent = false;
1103         }
1104         return wfMsgReal( $key, $args, true, $forcontent, false );
1105 }
1106
1107 /**
1108  * Really get a message
1109  *
1110  * @param $key String: key to get.
1111  * @param $args
1112  * @param $useDB Boolean
1113  * @param $forContent Mixed: Language code, or false for user lang, true for content lang.
1114  * @param $transform Boolean: Whether or not to transform the message.
1115  * @return String: the requested message.
1116  */
1117 function wfMsgReal( $key, $args, $useDB = true, $forContent = false, $transform = true ) {
1118         wfProfileIn( __METHOD__ );
1119         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
1120         $message = wfMsgReplaceArgs( $message, $args );
1121         wfProfileOut( __METHOD__ );
1122         return $message;
1123 }
1124
1125 /**
1126  * Fetch a message string value, but don't replace any keys yet.
1127  *
1128  * @param $key String
1129  * @param $useDB Bool
1130  * @param $langCode String: Code of the language to get the message for, or
1131  *                  behaves as a content language switch if it is a boolean.
1132  * @param $transform Boolean: whether to parse magic words, etc.
1133  * @return string
1134  */
1135 function wfMsgGetKey( $key, $useDB = true, $langCode = false, $transform = true ) {
1136         wfRunHooks( 'NormalizeMessageKey', array( &$key, &$useDB, &$langCode, &$transform ) );
1137
1138         $cache = MessageCache::singleton();
1139         $message = $cache->get( $key, $useDB, $langCode );
1140         if( $message === false ) {
1141                 $message = '&lt;' . htmlspecialchars( $key ) . '&gt;';
1142         } elseif ( $transform ) {
1143                 $message = $cache->transform( $message );
1144         }
1145         return $message;
1146 }
1147
1148 /**
1149  * Replace message parameter keys on the given formatted output.
1150  *
1151  * @param $message String
1152  * @param $args Array
1153  * @return string
1154  * @private
1155  */
1156 function wfMsgReplaceArgs( $message, $args ) {
1157         # Fix windows line-endings
1158         # Some messages are split with explode("\n", $msg)
1159         $message = str_replace( "\r", '', $message );
1160
1161         // Replace arguments
1162         if ( count( $args ) ) {
1163                 if ( is_array( $args[0] ) ) {
1164                         $args = array_values( $args[0] );
1165                 }
1166                 $replacementKeys = array();
1167                 foreach( $args as $n => $param ) {
1168                         $replacementKeys['$' . ( $n + 1 )] = $param;
1169                 }
1170                 $message = strtr( $message, $replacementKeys );
1171         }
1172
1173         return $message;
1174 }
1175
1176 /**
1177  * Return an HTML-escaped version of a message.
1178  * Parameter replacements, if any, are done *after* the HTML-escaping,
1179  * so parameters may contain HTML (eg links or form controls). Be sure
1180  * to pre-escape them if you really do want plaintext, or just wrap
1181  * the whole thing in htmlspecialchars().
1182  *
1183  * @param $key String
1184  * @param string ... parameters
1185  * @return string
1186  */
1187 function wfMsgHtml( $key ) {
1188         $args = func_get_args();
1189         array_shift( $args );
1190         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key ) ), $args );
1191 }
1192
1193 /**
1194  * Return an HTML version of message
1195  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
1196  * so parameters may contain HTML (eg links or form controls). Be sure
1197  * to pre-escape them if you really do want plaintext, or just wrap
1198  * the whole thing in htmlspecialchars().
1199  *
1200  * @param $key String
1201  * @param string ... parameters
1202  * @return string
1203  */
1204 function wfMsgWikiHtml( $key ) {
1205         $args = func_get_args();
1206         array_shift( $args );
1207         return wfMsgReplaceArgs(
1208                 MessageCache::singleton()->parse( wfMsgGetKey( $key ), null,
1209                 /* can't be set to false */ true, /* interface */ true )->getText(),
1210                 $args );
1211 }
1212
1213 /**
1214  * Returns message in the requested format
1215  * @param $key String: key of the message
1216  * @param $options Array: processing rules. Can take the following options:
1217  *   <i>parse</i>: parses wikitext to HTML
1218  *   <i>parseinline</i>: parses wikitext to HTML and removes the surrounding
1219  *       p's added by parser or tidy
1220  *   <i>escape</i>: filters message through htmlspecialchars
1221  *   <i>escapenoentities</i>: same, but allows entity references like &#160; through
1222  *   <i>replaceafter</i>: parameters are substituted after parsing or escaping
1223  *   <i>parsemag</i>: transform the message using magic phrases
1224  *   <i>content</i>: fetch message for content language instead of interface
1225  * Also can accept a single associative argument, of the form 'language' => 'xx':
1226  *   <i>language</i>: Language object or language code to fetch message for
1227  *       (overriden by <i>content</i>).
1228  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
1229  *
1230  * @return String
1231  */
1232 function wfMsgExt( $key, $options ) {
1233         $args = func_get_args();
1234         array_shift( $args );
1235         array_shift( $args );
1236         $options = (array)$options;
1237
1238         foreach( $options as $arrayKey => $option ) {
1239                 if( !preg_match( '/^[0-9]+|language$/', $arrayKey ) ) {
1240                         # An unknown index, neither numeric nor "language"
1241                         wfWarn( "wfMsgExt called with incorrect parameter key $arrayKey", 1, E_USER_WARNING );
1242                 } elseif( preg_match( '/^[0-9]+$/', $arrayKey ) && !in_array( $option,
1243                 array( 'parse', 'parseinline', 'escape', 'escapenoentities',
1244                 'replaceafter', 'parsemag', 'content' ) ) ) {
1245                         # A numeric index with unknown value
1246                         wfWarn( "wfMsgExt called with incorrect parameter $option", 1, E_USER_WARNING );
1247                 }
1248         }
1249
1250         if( in_array( 'content', $options, true ) ) {
1251                 $forContent = true;
1252                 $langCode = true;
1253                 $langCodeObj = null;
1254         } elseif( array_key_exists( 'language', $options ) ) {
1255                 $forContent = false;
1256                 $langCode = wfGetLangObj( $options['language'] );
1257                 $langCodeObj = $langCode;
1258         } else {
1259                 $forContent = false;
1260                 $langCode = false;
1261                 $langCodeObj = null;
1262         }
1263
1264         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
1265
1266         if( !in_array( 'replaceafter', $options, true ) ) {
1267                 $string = wfMsgReplaceArgs( $string, $args );
1268         }
1269
1270         $messageCache = MessageCache::singleton();
1271         if( in_array( 'parse', $options, true ) ) {
1272                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj )->getText();
1273         } elseif ( in_array( 'parseinline', $options, true ) ) {
1274                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj )->getText();
1275                 $m = array();
1276                 if( preg_match( '/^<p>(.*)\n?<\/p>\n?$/sU', $string, $m ) ) {
1277                         $string = $m[1];
1278                 }
1279         } elseif ( in_array( 'parsemag', $options, true ) ) {
1280                 $string = $messageCache->transform( $string,
1281                                 !$forContent, $langCodeObj );
1282         }
1283
1284         if ( in_array( 'escape', $options, true ) ) {
1285                 $string = htmlspecialchars ( $string );
1286         } elseif ( in_array( 'escapenoentities', $options, true ) ) {
1287                 $string = Sanitizer::escapeHtmlAllowEntities( $string );
1288         }
1289
1290         if( in_array( 'replaceafter', $options, true ) ) {
1291                 $string = wfMsgReplaceArgs( $string, $args );
1292         }
1293
1294         return $string;
1295 }
1296
1297 /**
1298  * Since wfMsg() and co suck, they don't return false if the message key they
1299  * looked up didn't exist but a XHTML string, this function checks for the
1300  * nonexistance of messages by checking the MessageCache::get() result directly.
1301  *
1302  * @param $key      String: the message key looked up
1303  * @return Boolean True if the message *doesn't* exist.
1304  */
1305 function wfEmptyMsg( $key ) {
1306         return MessageCache::singleton()->get( $key, /*useDB*/true, /*content*/false ) === false;
1307 }
1308
1309 /**
1310  * Throw a debugging exception. This function previously once exited the process,
1311  * but now throws an exception instead, with similar results.
1312  *
1313  * @param $msg String: message shown when dieing.
1314  */
1315 function wfDebugDieBacktrace( $msg = '' ) {
1316         throw new MWException( $msg );
1317 }
1318
1319 /**
1320  * Fetch server name for use in error reporting etc.
1321  * Use real server name if available, so we know which machine
1322  * in a server farm generated the current page.
1323  *
1324  * @return string
1325  */
1326 function wfHostname() {
1327         static $host;
1328         if ( is_null( $host ) ) {
1329                 if ( function_exists( 'posix_uname' ) ) {
1330                         // This function not present on Windows
1331                         $uname = posix_uname();
1332                 } else {
1333                         $uname = false;
1334                 }
1335                 if( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1336                         $host = $uname['nodename'];
1337                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1338                         # Windows computer name
1339                         $host = getenv( 'COMPUTERNAME' );
1340                 } else {
1341                         # This may be a virtual server.
1342                         $host = $_SERVER['SERVER_NAME'];
1343                 }
1344         }
1345         return $host;
1346 }
1347
1348 /**
1349  * Returns a HTML comment with the elapsed time since request.
1350  * This method has no side effects.
1351  *
1352  * @return string
1353  */
1354 function wfReportTime() {
1355         global $wgRequestTime, $wgShowHostnames;
1356
1357         $now = wfTime();
1358         $elapsed = $now - $wgRequestTime;
1359
1360         return $wgShowHostnames
1361                 ? sprintf( '<!-- Served by %s in %01.3f secs. -->', wfHostname(), $elapsed )
1362                 : sprintf( '<!-- Served in %01.3f secs. -->', $elapsed );
1363 }
1364
1365 /**
1366  * Safety wrapper for debug_backtrace().
1367  *
1368  * With Zend Optimizer 3.2.0 loaded, this causes segfaults under somewhat
1369  * murky circumstances, which may be triggered in part by stub objects
1370  * or other fancy talkin'.
1371  *
1372  * Will return an empty array if Zend Optimizer is detected or if
1373  * debug_backtrace is disabled, otherwise the output from
1374  * debug_backtrace() (trimmed).
1375  *
1376  * @return array of backtrace information
1377  */
1378 function wfDebugBacktrace( $limit = 0 ) {
1379         static $disabled = null;
1380
1381         if( extension_loaded( 'Zend Optimizer' ) ) {
1382                 wfDebug( "Zend Optimizer detected; skipping debug_backtrace for safety.\n" );
1383                 return array();
1384         }
1385
1386         if ( is_null( $disabled ) ) {
1387                 $disabled = false;
1388                 $functions = explode( ',', ini_get( 'disable_functions' ) );
1389                 $functions = array_map( 'trim', $functions );
1390                 $functions = array_map( 'strtolower', $functions );
1391                 if ( in_array( 'debug_backtrace', $functions ) ) {
1392                         wfDebug( "debug_backtrace is in disabled_functions\n" );
1393                         $disabled = true;
1394                 }
1395         }
1396         if ( $disabled ) {
1397                 return array();
1398         }
1399
1400         if ( $limit && version_compare( PHP_VERSION, '5.4.0', '>=' ) ) {
1401                 return array_slice( debug_backtrace( DEBUG_BACKTRACE_PROVIDE_OBJECT, 1 ), 1 );
1402         } else {
1403                 return array_slice( debug_backtrace(), 1 );
1404         }
1405 }
1406
1407 /**
1408  * Get a debug backtrace as a string
1409  *
1410  * @return string
1411  */
1412 function wfBacktrace() {
1413         global $wgCommandLineMode;
1414
1415         if ( $wgCommandLineMode ) {
1416                 $msg = '';
1417         } else {
1418                 $msg = "<ul>\n";
1419         }
1420         $backtrace = wfDebugBacktrace();
1421         foreach( $backtrace as $call ) {
1422                 if( isset( $call['file'] ) ) {
1423                         $f = explode( DIRECTORY_SEPARATOR, $call['file'] );
1424                         $file = $f[count( $f ) - 1];
1425                 } else {
1426                         $file = '-';
1427                 }
1428                 if( isset( $call['line'] ) ) {
1429                         $line = $call['line'];
1430                 } else {
1431                         $line = '-';
1432                 }
1433                 if ( $wgCommandLineMode ) {
1434                         $msg .= "$file line $line calls ";
1435                 } else {
1436                         $msg .= '<li>' . $file . ' line ' . $line . ' calls ';
1437                 }
1438                 if( !empty( $call['class'] ) ) {
1439                         $msg .= $call['class'] . $call['type'];
1440                 }
1441                 $msg .= $call['function'] . '()';
1442
1443                 if ( $wgCommandLineMode ) {
1444                         $msg .= "\n";
1445                 } else {
1446                         $msg .= "</li>\n";
1447                 }
1448         }
1449         if ( $wgCommandLineMode ) {
1450                 $msg .= "\n";
1451         } else {
1452                 $msg .= "</ul>\n";
1453         }
1454
1455         return $msg;
1456 }
1457
1458 /**
1459  * Get the name of the function which called this function
1460  *
1461  * @param $level Int
1462  * @return Bool|string
1463  */
1464 function wfGetCaller( $level = 2 ) {
1465         $backtrace = wfDebugBacktrace( $level );
1466         if ( isset( $backtrace[$level] ) ) {
1467                 return wfFormatStackFrame( $backtrace[$level] );
1468         } else {
1469                 $caller = 'unknown';
1470         }
1471         return $caller;
1472 }
1473
1474 /**
1475  * Return a string consisting of callers in the stack. Useful sometimes
1476  * for profiling specific points.
1477  *
1478  * @param $limit The maximum depth of the stack frame to return, or false for
1479  *               the entire stack.
1480  * @return String
1481  */
1482 function wfGetAllCallers( $limit = 3 ) {
1483         $trace = array_reverse( wfDebugBacktrace() );
1484         if ( !$limit || $limit > count( $trace ) - 1 ) {
1485                 $limit = count( $trace ) - 1;
1486         }
1487         $trace = array_slice( $trace, -$limit - 1, $limit );
1488         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1489 }
1490
1491 /**
1492  * Return a string representation of frame
1493  *
1494  * @param $frame Array
1495  * @return Bool
1496  */
1497 function wfFormatStackFrame( $frame ) {
1498         return isset( $frame['class'] ) ?
1499                 $frame['class'] . '::' . $frame['function'] :
1500                 $frame['function'];
1501 }
1502
1503
1504 /* Some generic result counters, pulled out of SearchEngine */
1505
1506
1507 /**
1508  * @todo document
1509  *
1510  * @param $offset Int
1511  * @param $limit Int
1512  * @return String
1513  */
1514 function wfShowingResults( $offset, $limit ) {
1515         global $wgLang;
1516         return wfMsgExt(
1517                 'showingresults',
1518                 array( 'parseinline' ),
1519                 $wgLang->formatNum( $limit ),
1520                 $wgLang->formatNum( $offset + 1 )
1521         );
1522 }
1523
1524 /**
1525  * Generate (prev x| next x) (20|50|100...) type links for paging
1526  *
1527  * @param $offset String
1528  * @param $limit Integer
1529  * @param $link String
1530  * @param $query String: optional URL query parameter string
1531  * @param $atend Bool: optional param for specified if this is the last page
1532  * @return String
1533  */
1534 function wfViewPrevNext( $offset, $limit, $link, $query = '', $atend = false ) {
1535         global $wgLang;
1536         $fmtLimit = $wgLang->formatNum( $limit );
1537         // @todo FIXME: Why on earth this needs one message for the text and another one for tooltip?
1538         # Get prev/next link display text
1539         $prev = wfMsgExt( 'prevn', array( 'parsemag', 'escape' ), $fmtLimit );
1540         $next = wfMsgExt( 'nextn', array( 'parsemag', 'escape' ), $fmtLimit );
1541         # Get prev/next link title text
1542         $pTitle = wfMsgExt( 'prevn-title', array( 'parsemag', 'escape' ), $fmtLimit );
1543         $nTitle = wfMsgExt( 'nextn-title', array( 'parsemag', 'escape' ), $fmtLimit );
1544         # Fetch the title object
1545         if( is_object( $link ) ) {
1546                 $title =& $link;
1547         } else {
1548                 $title = Title::newFromText( $link );
1549                 if( is_null( $title ) ) {
1550                         return false;
1551                 }
1552         }
1553         # Make 'previous' link
1554         if( 0 != $offset ) {
1555                 $po = $offset - $limit;
1556                 $po = max( $po, 0 );
1557                 $q = "limit={$limit}&offset={$po}";
1558                 if( $query != '' ) {
1559                         $q .= '&' . $query;
1560                 }
1561                 $plink = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$pTitle}\" class=\"mw-prevlink\">{$prev}</a>";
1562         } else {
1563                 $plink = $prev;
1564         }
1565         # Make 'next' link
1566         $no = $offset + $limit;
1567         $q = "limit={$limit}&offset={$no}";
1568         if( $query != '' ) {
1569                 $q .= '&' . $query;
1570         }
1571         if( $atend ) {
1572                 $nlink = $next;
1573         } else {
1574                 $nlink = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$nTitle}\" class=\"mw-nextlink\">{$next}</a>";
1575         }
1576         # Make links to set number of items per page
1577         $nums = $wgLang->pipeList( array(
1578                 wfNumLink( $offset, 20, $title, $query ),
1579                 wfNumLink( $offset, 50, $title, $query ),
1580                 wfNumLink( $offset, 100, $title, $query ),
1581                 wfNumLink( $offset, 250, $title, $query ),
1582                 wfNumLink( $offset, 500, $title, $query )
1583         ) );
1584         return wfMsgHtml( 'viewprevnext', $plink, $nlink, $nums );
1585 }
1586
1587 /**
1588  * Generate links for (20|50|100...) items-per-page links
1589  *
1590  * @param $offset String
1591  * @param $limit Integer
1592  * @param $title Title
1593  * @param $query String: optional URL query parameter string
1594  */
1595 function wfNumLink( $offset, $limit, $title, $query = '' ) {
1596         global $wgLang;
1597         if( $query == '' ) {
1598                 $q = '';
1599         } else {
1600                 $q = $query.'&';
1601         }
1602         $q .= "limit={$limit}&offset={$offset}";
1603         $fmtLimit = $wgLang->formatNum( $limit );
1604         $lTitle = wfMsgExt( 'shown-title', array( 'parsemag', 'escape' ), $limit );
1605         $s = '<a href="' . $title->escapeLocalURL( $q ) . "\" title=\"{$lTitle}\" class=\"mw-numlink\">{$fmtLimit}</a>";
1606         return $s;
1607 }
1608
1609 /**
1610  * @todo document
1611  * @todo FIXME: We may want to blacklist some broken browsers
1612  *
1613  * @param $force Bool
1614  * @return bool Whereas client accept gzip compression
1615  */
1616 function wfClientAcceptsGzip( $force = false ) {
1617         static $result = null;
1618         if ( $result === null || $force ) {
1619                 $result = false;
1620                 if( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1621                         # @todo FIXME: We may want to blacklist some broken browsers
1622                         $m = array();
1623                         if( preg_match(
1624                                 '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1625                                 $_SERVER['HTTP_ACCEPT_ENCODING'],
1626                                 $m )
1627                         )
1628                         {
1629                                 if( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1630                                         $result = false;
1631                                         return $result;
1632                                 }
1633                                 wfDebug( " accepts gzip\n" );
1634                                 $result = true;
1635                         }
1636                 }
1637         }
1638         return $result;
1639 }
1640
1641 /**
1642  * Obtain the offset and limit values from the request string;
1643  * used in special pages
1644  *
1645  * @param $deflimit Int default limit if none supplied
1646  * @param $optionname String Name of a user preference to check against
1647  * @return array
1648  *
1649  */
1650 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
1651         global $wgRequest;
1652         return $wgRequest->getLimitOffset( $deflimit, $optionname );
1653 }
1654
1655 /**
1656  * Escapes the given text so that it may be output using addWikiText()
1657  * without any linking, formatting, etc. making its way through. This
1658  * is achieved by substituting certain characters with HTML entities.
1659  * As required by the callers, <nowiki> is not used.
1660  *
1661  * @param $text String: text to be escaped
1662  * @return String
1663  */
1664 function wfEscapeWikiText( $text ) {
1665         $text = strtr( "\n$text", array(
1666                 '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
1667                 '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
1668                 '{' => '&#123;', '|' => '&#124;', '}' => '&#125;',
1669                 "\n#" => "\n&#35;", "\n*" => "\n&#42;",
1670                 "\n:" => "\n&#58;", "\n;" => "\n&#59;",
1671                 '://' => '&#58;//', 'ISBN ' => 'ISBN&#32;', 'RFC ' => 'RFC&#32;',
1672         ) );
1673         return substr( $text, 1 );
1674 }
1675
1676 /**
1677  * Get the current unix timetstamp with microseconds.  Useful for profiling
1678  * @return Float
1679  */
1680 function wfTime() {
1681         return microtime( true );
1682 }
1683
1684 /**
1685  * Sets dest to source and returns the original value of dest
1686  * If source is NULL, it just returns the value, it doesn't set the variable
1687  * If force is true, it will set the value even if source is NULL
1688  *
1689  * @param $dest Mixed
1690  * @param $source Mixed
1691  * @param $force Bool
1692  * @return Mixed
1693  */
1694 function wfSetVar( &$dest, $source, $force = false ) {
1695         $temp = $dest;
1696         if ( !is_null( $source ) || $force ) {
1697                 $dest = $source;
1698         }
1699         return $temp;
1700 }
1701
1702 /**
1703  * As for wfSetVar except setting a bit
1704  *
1705  * @param $dest Int
1706  * @param $bit Int
1707  * @param $state Bool
1708  */
1709 function wfSetBit( &$dest, $bit, $state = true ) {
1710         $temp = (bool)( $dest & $bit );
1711         if ( !is_null( $state ) ) {
1712                 if ( $state ) {
1713                         $dest |= $bit;
1714                 } else {
1715                         $dest &= ~$bit;
1716                 }
1717         }
1718         return $temp;
1719 }
1720
1721 /**
1722  * Windows-compatible version of escapeshellarg()
1723  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
1724  * function puts single quotes in regardless of OS.
1725  *
1726  * Also fixes the locale problems on Linux in PHP 5.2.6+ (bug backported to
1727  * earlier distro releases of PHP)
1728  *
1729  * @param varargs
1730  * @return String
1731  */
1732 function wfEscapeShellArg( ) {
1733         wfInitShellLocale();
1734
1735         $args = func_get_args();
1736         $first = true;
1737         $retVal = '';
1738         foreach ( $args as $arg ) {
1739                 if ( !$first ) {
1740                         $retVal .= ' ';
1741                 } else {
1742                         $first = false;
1743                 }
1744
1745                 if ( wfIsWindows() ) {
1746                         // Escaping for an MSVC-style command line parser and CMD.EXE
1747                         // Refs:
1748                         //  * http://web.archive.org/web/20020708081031/http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
1749                         //  * http://technet.microsoft.com/en-us/library/cc723564.aspx
1750                         //  * Bug #13518
1751                         //  * CR r63214
1752                         // Double the backslashes before any double quotes. Escape the double quotes.
1753                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
1754                         $arg = '';
1755                         $iteration = 0;
1756                         foreach ( $tokens as $token ) {
1757                                 if ( $iteration % 2 == 1 ) {
1758                                         // Delimiter, a double quote preceded by zero or more slashes
1759                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
1760                                 } elseif ( $iteration % 4 == 2 ) {
1761                                         // ^ in $token will be outside quotes, need to be escaped
1762                                         $arg .= str_replace( '^', '^^', $token );
1763                                 } else { // $iteration % 4 == 0
1764                                         // ^ in $token will appear inside double quotes, so leave as is
1765                                         $arg .= $token;
1766                                 }
1767                                 $iteration++;
1768                         }
1769                         // Double the backslashes before the end of the string, because
1770                         // we will soon add a quote
1771                         $m = array();
1772                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
1773                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
1774                         }
1775
1776                         // Add surrounding quotes
1777                         $retVal .= '"' . $arg . '"';
1778                 } else {
1779                         $retVal .= escapeshellarg( $arg );
1780                 }
1781         }
1782         return $retVal;
1783 }
1784
1785 /**
1786  * wfMerge attempts to merge differences between three texts.
1787  * Returns true for a clean merge and false for failure or a conflict.
1788  *
1789  * @param $old String
1790  * @param $mine String
1791  * @param $yours String
1792  * @param $result String
1793  * @return Bool
1794  */
1795 function wfMerge( $old, $mine, $yours, &$result ) {
1796         global $wgDiff3;
1797
1798         # This check may also protect against code injection in
1799         # case of broken installations.
1800         wfSuppressWarnings();
1801         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
1802         wfRestoreWarnings();
1803
1804         if( !$haveDiff3 ) {
1805                 wfDebug( "diff3 not found\n" );
1806                 return false;
1807         }
1808
1809         # Make temporary files
1810         $td = wfTempDir();
1811         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1812         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
1813         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
1814
1815         fwrite( $oldtextFile, $old );
1816         fclose( $oldtextFile );
1817         fwrite( $mytextFile, $mine );
1818         fclose( $mytextFile );
1819         fwrite( $yourtextFile, $yours );
1820         fclose( $yourtextFile );
1821
1822         # Check for a conflict
1823         $cmd = $wgDiff3 . ' -a --overlap-only ' .
1824                 wfEscapeShellArg( $mytextName ) . ' ' .
1825                 wfEscapeShellArg( $oldtextName ) . ' ' .
1826                 wfEscapeShellArg( $yourtextName );
1827         $handle = popen( $cmd, 'r' );
1828
1829         if( fgets( $handle, 1024 ) ) {
1830                 $conflict = true;
1831         } else {
1832                 $conflict = false;
1833         }
1834         pclose( $handle );
1835
1836         # Merge differences
1837         $cmd = $wgDiff3 . ' -a -e --merge ' .
1838                 wfEscapeShellArg( $mytextName, $oldtextName, $yourtextName );
1839         $handle = popen( $cmd, 'r' );
1840         $result = '';
1841         do {
1842                 $data = fread( $handle, 8192 );
1843                 if ( strlen( $data ) == 0 ) {
1844                         break;
1845                 }
1846                 $result .= $data;
1847         } while ( true );
1848         pclose( $handle );
1849         unlink( $mytextName );
1850         unlink( $oldtextName );
1851         unlink( $yourtextName );
1852
1853         if ( $result === '' && $old !== '' && !$conflict ) {
1854                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
1855                 $conflict = true;
1856         }
1857         return !$conflict;
1858 }
1859
1860 /**
1861  * Returns unified plain-text diff of two texts.
1862  * Useful for machine processing of diffs.
1863  *
1864  * @param $before String: the text before the changes.
1865  * @param $after String: the text after the changes.
1866  * @param $params String: command-line options for the diff command.
1867  * @return String: unified diff of $before and $after
1868  */
1869 function wfDiff( $before, $after, $params = '-u' ) {
1870         if ( $before == $after ) {
1871                 return '';
1872         }
1873
1874         global $wgDiff;
1875         wfSuppressWarnings();
1876         $haveDiff = $wgDiff && file_exists( $wgDiff );
1877         wfRestoreWarnings();
1878
1879         # This check may also protect against code injection in
1880         # case of broken installations.
1881         if( !$haveDiff ) {
1882                 wfDebug( "diff executable not found\n" );
1883                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
1884                 $format = new UnifiedDiffFormatter();
1885                 return $format->format( $diffs );
1886         }
1887
1888         # Make temporary files
1889         $td = wfTempDir();
1890         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
1891         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
1892
1893         fwrite( $oldtextFile, $before );
1894         fclose( $oldtextFile );
1895         fwrite( $newtextFile, $after );
1896         fclose( $newtextFile );
1897
1898         // Get the diff of the two files
1899         $cmd = "$wgDiff " . $params . ' ' . wfEscapeShellArg( $oldtextName, $newtextName );
1900
1901         $h = popen( $cmd, 'r' );
1902
1903         $diff = '';
1904
1905         do {
1906                 $data = fread( $h, 8192 );
1907                 if ( strlen( $data ) == 0 ) {
1908                         break;
1909                 }
1910                 $diff .= $data;
1911         } while ( true );
1912
1913         // Clean up
1914         pclose( $h );
1915         unlink( $oldtextName );
1916         unlink( $newtextName );
1917
1918         // Kill the --- and +++ lines. They're not useful.
1919         $diff_lines = explode( "\n", $diff );
1920         if ( strpos( $diff_lines[0], '---' ) === 0 ) {
1921                 unset( $diff_lines[0] );
1922         }
1923         if ( strpos( $diff_lines[1], '+++' ) === 0 ) {
1924                 unset( $diff_lines[1] );
1925         }
1926
1927         $diff = implode( "\n", $diff_lines );
1928
1929         return $diff;
1930 }
1931
1932 /**
1933  * A wrapper around the PHP function var_export().
1934  * Either print it or add it to the regular output ($wgOut).
1935  *
1936  * @param $var A PHP variable to dump.
1937  */
1938 function wfVarDump( $var ) {
1939         global $wgOut;
1940         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
1941         if ( headers_sent() || !isset( $wgOut ) || !is_object( $wgOut ) ) {
1942                 print $s;
1943         } else {
1944                 $wgOut->addHTML( $s );
1945         }
1946 }
1947
1948 /**
1949  * Provide a simple HTTP error.
1950  *
1951  * @param $code Int|String
1952  * @param $label String
1953  * @param $desc String
1954  */
1955 function wfHttpError( $code, $label, $desc ) {
1956         global $wgOut;
1957         $wgOut->disable();
1958         header( "HTTP/1.0 $code $label" );
1959         header( "Status: $code $label" );
1960         $wgOut->sendCacheControl();
1961
1962         header( 'Content-type: text/html; charset=utf-8' );
1963         print "<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">".
1964                 '<html><head><title>' .
1965                 htmlspecialchars( $label ) .
1966                 '</title></head><body><h1>' .
1967                 htmlspecialchars( $label ) .
1968                 '</h1><p>' .
1969                 nl2br( htmlspecialchars( $desc ) ) .
1970                 "</p></body></html>\n";
1971 }
1972
1973 /**
1974  * Clear away any user-level output buffers, discarding contents.
1975  *
1976  * Suitable for 'starting afresh', for instance when streaming
1977  * relatively large amounts of data without buffering, or wanting to
1978  * output image files without ob_gzhandler's compression.
1979  *
1980  * The optional $resetGzipEncoding parameter controls suppression of
1981  * the Content-Encoding header sent by ob_gzhandler; by default it
1982  * is left. See comments for wfClearOutputBuffers() for why it would
1983  * be used.
1984  *
1985  * Note that some PHP configuration options may add output buffer
1986  * layers which cannot be removed; these are left in place.
1987  *
1988  * @param $resetGzipEncoding Bool
1989  */
1990 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
1991         if( $resetGzipEncoding ) {
1992                 // Suppress Content-Encoding and Content-Length
1993                 // headers from 1.10+s wfOutputHandler
1994                 global $wgDisableOutputCompression;
1995                 $wgDisableOutputCompression = true;
1996         }
1997         while( $status = ob_get_status() ) {
1998                 if( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
1999                         // Probably from zlib.output_compression or other
2000                         // PHP-internal setting which can't be removed.
2001                         //
2002                         // Give up, and hope the result doesn't break
2003                         // output behavior.
2004                         break;
2005                 }
2006                 if( !ob_end_clean() ) {
2007                         // Could not remove output buffer handler; abort now
2008                         // to avoid getting in some kind of infinite loop.
2009                         break;
2010                 }
2011                 if( $resetGzipEncoding ) {
2012                         if( $status['name'] == 'ob_gzhandler' ) {
2013                                 // Reset the 'Content-Encoding' field set by this handler
2014                                 // so we can start fresh.
2015                                 if ( function_exists( 'header_remove' ) ) {
2016                                         // Available since PHP 5.3.0
2017                                         header_remove( 'Content-Encoding' );
2018                                 } else {
2019                                         // We need to provide a valid content-coding. See bug 28069
2020                                         header( 'Content-Encoding: identity' );
2021                                 }
2022                                 break;
2023                         }
2024                 }
2025         }
2026 }
2027
2028 /**
2029  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
2030  *
2031  * Clear away output buffers, but keep the Content-Encoding header
2032  * produced by ob_gzhandler, if any.
2033  *
2034  * This should be used for HTTP 304 responses, where you need to
2035  * preserve the Content-Encoding header of the real result, but
2036  * also need to suppress the output of ob_gzhandler to keep to spec
2037  * and avoid breaking Firefox in rare cases where the headers and
2038  * body are broken over two packets.
2039  */
2040 function wfClearOutputBuffers() {
2041         wfResetOutputBuffers( false );
2042 }
2043
2044 /**
2045  * Converts an Accept-* header into an array mapping string values to quality
2046  * factors
2047  *
2048  * @param $accept String
2049  * @param $def String default
2050  * @return Array
2051  */
2052 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
2053         # No arg means accept anything (per HTTP spec)
2054         if( !$accept ) {
2055                 return array( $def => 1.0 );
2056         }
2057
2058         $prefs = array();
2059
2060         $parts = explode( ',', $accept );
2061
2062         foreach( $parts as $part ) {
2063                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
2064                 $values = explode( ';', trim( $part ) );
2065                 $match = array();
2066                 if ( count( $values ) == 1 ) {
2067                         $prefs[$values[0]] = 1.0;
2068                 } elseif ( preg_match( '/q\s*=\s*(\d*\.\d+)/', $values[1], $match ) ) {
2069                         $prefs[$values[0]] = floatval( $match[1] );
2070                 }
2071         }
2072
2073         return $prefs;
2074 }
2075
2076 /**
2077  * Checks if a given MIME type matches any of the keys in the given
2078  * array. Basic wildcards are accepted in the array keys.
2079  *
2080  * Returns the matching MIME type (or wildcard) if a match, otherwise
2081  * NULL if no match.
2082  *
2083  * @param $type String
2084  * @param $avail Array
2085  * @return string
2086  * @private
2087  */
2088 function mimeTypeMatch( $type, $avail ) {
2089         if( array_key_exists( $type, $avail ) ) {
2090                 return $type;
2091         } else {
2092                 $parts = explode( '/', $type );
2093                 if( array_key_exists( $parts[0] . '/*', $avail ) ) {
2094                         return $parts[0] . '/*';
2095                 } elseif( array_key_exists( '*/*', $avail ) ) {
2096                         return '*/*';
2097                 } else {
2098                         return null;
2099                 }
2100         }
2101 }
2102
2103 /**
2104  * Returns the 'best' match between a client's requested internet media types
2105  * and the server's list of available types. Each list should be an associative
2106  * array of type to preference (preference is a float between 0.0 and 1.0).
2107  * Wildcards in the types are acceptable.
2108  *
2109  * @param $cprefs Array: client's acceptable type list
2110  * @param $sprefs Array: server's offered types
2111  * @return string
2112  *
2113  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
2114  * XXX: generalize to negotiate other stuff
2115  */
2116 function wfNegotiateType( $cprefs, $sprefs ) {
2117         $combine = array();
2118
2119         foreach( array_keys($sprefs) as $type ) {
2120                 $parts = explode( '/', $type );
2121                 if( $parts[1] != '*' ) {
2122                         $ckey = mimeTypeMatch( $type, $cprefs );
2123                         if( $ckey ) {
2124                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
2125                         }
2126                 }
2127         }
2128
2129         foreach( array_keys( $cprefs ) as $type ) {
2130                 $parts = explode( '/', $type );
2131                 if( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
2132                         $skey = mimeTypeMatch( $type, $sprefs );
2133                         if( $skey ) {
2134                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
2135                         }
2136                 }
2137         }
2138
2139         $bestq = 0;
2140         $besttype = null;
2141
2142         foreach( array_keys( $combine ) as $type ) {
2143                 if( $combine[$type] > $bestq ) {
2144                         $besttype = $type;
2145                         $bestq = $combine[$type];
2146                 }
2147         }
2148
2149         return $besttype;
2150 }
2151
2152 /**
2153  * Reference-counted warning suppression
2154  *
2155  * @param $end Bool
2156  */
2157 function wfSuppressWarnings( $end = false ) {
2158         static $suppressCount = 0;
2159         static $originalLevel = false;
2160
2161         if ( $end ) {
2162                 if ( $suppressCount ) {
2163                         --$suppressCount;
2164                         if ( !$suppressCount ) {
2165                                 error_reporting( $originalLevel );
2166                         }
2167                 }
2168         } else {
2169                 if ( !$suppressCount ) {
2170                         // E_DEPRECATED is undefined in PHP 5.2
2171                         if( !defined( 'E_DEPRECATED' ) ){
2172                                 define( 'E_DEPRECATED', 8192 );
2173                         }
2174                         $originalLevel = error_reporting( E_ALL & ~( E_WARNING | E_NOTICE | E_USER_WARNING | E_USER_NOTICE | E_DEPRECATED ) );
2175                 }
2176                 ++$suppressCount;
2177         }
2178 }
2179
2180 /**
2181  * Restore error level to previous value
2182  */
2183 function wfRestoreWarnings() {
2184         wfSuppressWarnings( true );
2185 }
2186
2187 # Autodetect, convert and provide timestamps of various types
2188
2189 /**
2190  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
2191  */
2192 define( 'TS_UNIX', 0 );
2193
2194 /**
2195  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
2196  */
2197 define( 'TS_MW', 1 );
2198
2199 /**
2200  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
2201  */
2202 define( 'TS_DB', 2 );
2203
2204 /**
2205  * RFC 2822 format, for E-mail and HTTP headers
2206  */
2207 define( 'TS_RFC2822', 3 );
2208
2209 /**
2210  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
2211  *
2212  * This is used by Special:Export
2213  */
2214 define( 'TS_ISO_8601', 4 );
2215
2216 /**
2217  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
2218  *
2219  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
2220  *       DateTime tag and page 36 for the DateTimeOriginal and
2221  *       DateTimeDigitized tags.
2222  */
2223 define( 'TS_EXIF', 5 );
2224
2225 /**
2226  * Oracle format time.
2227  */
2228 define( 'TS_ORACLE', 6 );
2229
2230 /**
2231  * Postgres format time.
2232  */
2233 define( 'TS_POSTGRES', 7 );
2234
2235 /**
2236  * DB2 format time
2237  */
2238 define( 'TS_DB2', 8 );
2239
2240 /**
2241  * ISO 8601 basic format with no timezone: 19860209T200000Z.  This is used by ResourceLoader
2242  */
2243 define( 'TS_ISO_8601_BASIC', 9 );
2244
2245 /**
2246  * Get a timestamp string in one of various formats
2247  *
2248  * @param $outputtype Mixed: A timestamp in one of the supported formats, the
2249  *                    function will autodetect which format is supplied and act
2250  *                    accordingly.
2251  * @param $ts Mixed: the timestamp to convert or 0 for the current timestamp
2252  * @return Mixed: String / false The same date in the format specified in $outputtype or false
2253  */
2254 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
2255         $uts = 0;
2256         $da = array();
2257         $strtime = '';
2258
2259         if ( !$ts ) { // We want to catch 0, '', null... but not date strings starting with a letter.
2260                 $uts = time();
2261                 $strtime = "@$uts";
2262         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2263                 # TS_DB
2264         } elseif ( preg_match( '/^(\d{4}):(\d\d):(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
2265                 # TS_EXIF
2266         } elseif ( preg_match( '/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/D', $ts, $da ) ) {
2267                 # TS_MW
2268         } elseif ( preg_match( '/^-?\d{1,13}$/D', $ts ) ) {
2269                 # TS_UNIX
2270                 $uts = $ts;
2271                 $strtime = "@$ts"; // Undocumented?
2272         } elseif ( preg_match( '/^\d{2}-\d{2}-\d{4} \d{2}:\d{2}:\d{2}.\d{6}$/', $ts ) ) {
2273                 # TS_ORACLE // session altered to DD-MM-YYYY HH24:MI:SS.FF6
2274                 $strtime = preg_replace( '/(\d\d)\.(\d\d)\.(\d\d)(\.(\d+))?/', "$1:$2:$3",
2275                                 str_replace( '+00:00', 'UTC', $ts ) );
2276         } elseif ( preg_match( '/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2277                 # TS_ISO_8601
2278         } elseif ( preg_match( '/^(\d{4})(\d{2})(\d{2})T(\d{2})(\d{2})(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
2279                 #TS_ISO_8601_BASIC
2280         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d*[\+\- ](\d\d)$/', $ts, $da ) ) {
2281                 # TS_POSTGRES
2282         } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d* GMT$/', $ts, $da ) ) {
2283                 # TS_POSTGRES
2284         } elseif (preg_match('/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.\d\d\d$/',$ts,$da)) {
2285                 # TS_DB2
2286         } elseif ( preg_match( '/^[ \t\r\n]*([A-Z][a-z]{2},[ \t\r\n]*)?' . # Day of week
2287                                                         '\d\d?[ \t\r\n]*[A-Z][a-z]{2}[ \t\r\n]*\d{2}(?:\d{2})?' .  # dd Mon yyyy
2288                                                         '[ \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
2289                 # TS_RFC2822, accepting a trailing comment. See http://www.squid-cache.org/mail-archive/squid-users/200307/0122.html / r77171
2290                 # The regex is a superset of rfc2822 for readability
2291                 $strtime = strtok( $ts, ';' );
2292         } 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 ) ) {
2293                 # TS_RFC850
2294                 $strtime = $ts;
2295         } 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 ) ) {
2296                 # asctime
2297                 $strtime = $ts;
2298         } else {
2299                 # Bogus value...
2300                 wfDebug("wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n");
2301
2302                 return false;
2303         }
2304
2305         static $formats = array(
2306                 TS_UNIX => 'U',
2307                 TS_MW => 'YmdHis',
2308                 TS_DB => 'Y-m-d H:i:s',
2309                 TS_ISO_8601 => 'Y-m-d\TH:i:s\Z',
2310                 TS_ISO_8601_BASIC => 'Ymd\THis\Z',
2311                 TS_EXIF => 'Y:m:d H:i:s', // This shouldn't ever be used, but is included for completeness
2312                 TS_RFC2822 => 'D, d M Y H:i:s',
2313                 TS_ORACLE => 'd-m-Y H:i:s.000000', // Was 'd-M-y h.i.s A' . ' +00:00' before r51500
2314                 TS_POSTGRES => 'Y-m-d H:i:s',
2315                 TS_DB2 => 'Y-m-d H:i:s',
2316         );
2317
2318         if ( !isset( $formats[$outputtype] ) ) {
2319                 throw new MWException( 'wfTimestamp() called with illegal output type.' );
2320         }
2321
2322         if ( function_exists( "date_create" ) ) {
2323                 if ( count( $da ) ) {
2324                         $ds = sprintf("%04d-%02d-%02dT%02d:%02d:%02d.00+00:00",
2325                                 (int)$da[1], (int)$da[2], (int)$da[3],
2326                                 (int)$da[4], (int)$da[5], (int)$da[6]);
2327
2328                         $d = date_create( $ds, new DateTimeZone( 'GMT' ) );
2329                 } elseif ( $strtime ) {
2330                         $d = date_create( $strtime, new DateTimeZone( 'GMT' ) );
2331                 } else {
2332                         return false;
2333                 }
2334
2335                 if ( !$d ) {
2336                         wfDebug("wfTimestamp() fed bogus time value: $outputtype; $ts\n");
2337                         return false;
2338                 }
2339
2340                 $output = $d->format( $formats[$outputtype] );
2341         } else {
2342                 if ( count( $da ) ) {
2343                         // Warning! gmmktime() acts oddly if the month or day is set to 0
2344                         // We may want to handle that explicitly at some point
2345                         $uts = gmmktime( (int)$da[4], (int)$da[5], (int)$da[6],
2346                                 (int)$da[2], (int)$da[3], (int)$da[1] );
2347                 } elseif ( $strtime ) {
2348                         $uts = strtotime( $strtime );
2349                 }
2350
2351                 if ( $uts === false ) {
2352                         wfDebug("wfTimestamp() can't parse the timestamp (non 32-bit time? Update php): $outputtype; $ts\n");
2353                         return false;
2354                 }
2355
2356                 if ( TS_UNIX == $outputtype ) {
2357                         return $uts;
2358                 }
2359                 $output = gmdate( $formats[$outputtype], $uts );
2360         }
2361
2362         if ( ( $outputtype == TS_RFC2822 ) || ( $outputtype == TS_POSTGRES ) ) {
2363                 $output .= ' GMT';
2364         }
2365
2366         return $output;
2367 }
2368
2369 /**
2370  * Return a formatted timestamp, or null if input is null.
2371  * For dealing with nullable timestamp columns in the database.
2372  *
2373  * @param $outputtype Integer
2374  * @param $ts String
2375  * @return String
2376  */
2377 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2378         if( is_null( $ts ) ) {
2379                 return null;
2380         } else {
2381                 return wfTimestamp( $outputtype, $ts );
2382         }
2383 }
2384
2385 /**
2386  * Convenience function; returns MediaWiki timestamp for the present time.
2387  *
2388  * @return string
2389  */
2390 function wfTimestampNow() {
2391         # return NOW
2392         return wfTimestamp( TS_MW, time() );
2393 }
2394
2395 /**
2396  * Check if the operating system is Windows
2397  *
2398  * @return Bool: true if it's Windows, False otherwise.
2399  */
2400 function wfIsWindows() {
2401         static $isWindows = null;
2402         if ( $isWindows === null ) {
2403                 $isWindows = substr( php_uname(), 0, 7 ) == 'Windows';
2404         }
2405         return $isWindows;
2406 }
2407
2408 /**
2409  * Check if we are running under HipHop
2410  *
2411  * @return Bool
2412  */
2413 function wfIsHipHop() {
2414         return function_exists( 'hphp_thread_set_warmup_enabled' );
2415 }
2416
2417 /**
2418  * Swap two variables
2419  *
2420  * @param $x Mixed
2421  * @param $y Mixed
2422  */
2423 function swap( &$x, &$y ) {
2424         $z = $x;
2425         $x = $y;
2426         $y = $z;
2427 }
2428
2429 /**
2430  * Tries to get the system directory for temporary files. The TMPDIR, TMP, and
2431  * TEMP environment variables are then checked in sequence, and if none are set
2432  * try sys_get_temp_dir() for PHP >= 5.2.1. All else fails, return /tmp for Unix
2433  * or C:\Windows\Temp for Windows and hope for the best.
2434  * It is common to call it with tempnam().
2435  *
2436  * NOTE: When possible, use instead the tmpfile() function to create
2437  * temporary files to avoid race conditions on file creation, etc.
2438  *
2439  * @return String
2440  */
2441 function wfTempDir() {
2442         foreach( array( 'TMPDIR', 'TMP', 'TEMP' ) as $var ) {
2443                 $tmp = getenv( $var );
2444                 if( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
2445                         return $tmp;
2446                 }
2447         }
2448         if( function_exists( 'sys_get_temp_dir' ) ) {
2449                 return sys_get_temp_dir();
2450         }
2451         # Usual defaults
2452         return wfIsWindows() ? 'C:\Windows\Temp' : '/tmp';
2453 }
2454
2455 /**
2456  * Make directory, and make all parent directories if they don't exist
2457  *
2458  * @param $dir String: full path to directory to create
2459  * @param $mode Integer: chmod value to use, default is $wgDirectoryMode
2460  * @param $caller String: optional caller param for debugging.
2461  * @return bool
2462  */
2463 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2464         global $wgDirectoryMode;
2465
2466         if ( !is_null( $caller ) ) {
2467                 wfDebug( "$caller: called wfMkdirParents($dir)" );
2468         }
2469
2470         if( strval( $dir ) === '' || file_exists( $dir ) ) {
2471                 return true;
2472         }
2473
2474         $dir = str_replace( array( '\\', '/' ), DIRECTORY_SEPARATOR, $dir );
2475
2476         if ( is_null( $mode ) ) {
2477                 $mode = $wgDirectoryMode;
2478         }
2479
2480         // Turn off the normal warning, we're doing our own below
2481         wfSuppressWarnings();
2482         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2483         wfRestoreWarnings();
2484
2485         if( !$ok ) {
2486                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2487                 trigger_error( __FUNCTION__ . ": failed to mkdir \"$dir\" mode $mode", E_USER_WARNING );
2488         }
2489         return $ok;
2490 }
2491
2492 /**
2493  * Increment a statistics counter
2494  *
2495  * @param $key String
2496  * @param $count Int
2497  */
2498 function wfIncrStats( $key, $count = 1 ) {
2499         global $wgStatsMethod;
2500
2501         $count = intval( $count );
2502
2503         if( $wgStatsMethod == 'udp' ) {
2504                 global $wgUDPProfilerHost, $wgUDPProfilerPort, $wgDBname, $wgAggregateStatsID;
2505                 static $socket;
2506
2507                 $id = $wgAggregateStatsID !== false ? $wgAggregateStatsID : $wgDBname;
2508
2509                 if ( !$socket ) {
2510                         $socket = socket_create( AF_INET, SOCK_DGRAM, SOL_UDP );
2511                         $statline = "stats/{$id} - {$count} 1 1 1 1 -total\n";
2512                         socket_sendto(
2513                                 $socket,
2514                                 $statline,
2515                                 strlen( $statline ),
2516                                 0,
2517                                 $wgUDPProfilerHost,
2518                                 $wgUDPProfilerPort
2519                         );
2520                 }
2521                 $statline = "stats/{$id} - {$count} 1 1 1 1 {$key}\n";
2522                 wfSuppressWarnings();
2523                 socket_sendto(
2524                         $socket,
2525                         $statline,
2526                         strlen( $statline ),
2527                         0,
2528                         $wgUDPProfilerHost,
2529                         $wgUDPProfilerPort
2530                 );
2531                 wfRestoreWarnings();
2532         } elseif( $wgStatsMethod == 'cache' ) {
2533                 global $wgMemc;
2534                 $key = wfMemcKey( 'stats', $key );
2535                 if ( is_null( $wgMemc->incr( $key, $count ) ) ) {
2536                         $wgMemc->add( $key, $count );
2537                 }
2538         } else {
2539                 // Disabled
2540         }
2541 }
2542
2543 /**
2544  * @param $nr Mixed: the number to format
2545  * @param $acc Integer: the number of digits after the decimal point, default 2
2546  * @param $round Boolean: whether or not to round the value, default true
2547  * @return float
2548  */
2549 function wfPercent( $nr, $acc = 2, $round = true ) {
2550         $ret = sprintf( "%.${acc}f", $nr );
2551         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2552 }
2553
2554 /**
2555  * Find out whether or not a mixed variable exists in a string
2556  *
2557  * @param $needle String
2558  * @param $str String
2559  * @param $insensitive Boolean
2560  * @return Boolean
2561  */
2562 function in_string( $needle, $str, $insensitive = false ) {
2563         $func = 'strpos';
2564         if( $insensitive ) $func = 'stripos';
2565
2566         return $func( $str, $needle ) !== false;
2567 }
2568
2569 /**
2570  * Make a list item, used by various special pages
2571  *
2572  * @param $page String Page link
2573  * @param $details String Text between brackets
2574  * @param $oppositedm Boolean   Add the direction mark opposite to your
2575  *                                                              language, to display text properly
2576  * @return String
2577  */
2578 function wfSpecialList( $page, $details, $oppositedm = true ) {
2579         global $wgLang;
2580         $dirmark = ( $oppositedm ? $wgLang->getDirMark( true ) : '' ) .
2581                 $wgLang->getDirMark();
2582         $details = $details ? $dirmark . " ($details)" : '';
2583         return $page . $details;
2584 }
2585
2586 /**
2587  * Safety wrapper around ini_get() for boolean settings.
2588  * The values returned from ini_get() are pre-normalized for settings
2589  * set via php.ini or php_flag/php_admin_flag... but *not*
2590  * for those set via php_value/php_admin_value.
2591  *
2592  * It's fairly common for people to use php_value instead of php_flag,
2593  * which can leave you with an 'off' setting giving a false positive
2594  * for code that just takes the ini_get() return value as a boolean.
2595  *
2596  * To make things extra interesting, setting via php_value accepts
2597  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2598  * Unrecognized values go false... again opposite PHP's own coercion
2599  * from string to bool.
2600  *
2601  * Luckily, 'properly' set settings will always come back as '0' or '1',
2602  * so we only have to worry about them and the 'improper' settings.
2603  *
2604  * I frickin' hate PHP... :P
2605  *
2606  * @param $setting String
2607  * @return Bool
2608  */
2609 function wfIniGetBool( $setting ) {
2610         $val = ini_get( $setting );
2611         // 'on' and 'true' can't have whitespace around them, but '1' can.
2612         return strtolower( $val ) == 'on'
2613                 || strtolower( $val ) == 'true'
2614                 || strtolower( $val ) == 'yes'
2615                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2616 }
2617
2618 /**
2619  * Wrapper function for PHP's dl(). This doesn't work in most situations from
2620  * PHP 5.3 onward, and is usually disabled in shared environments anyway.
2621  *
2622  * @param $extension String A PHP extension. The file suffix (.so or .dll)
2623  *                          should be omitted
2624  * @param $fileName String Name of the library, if not $extension.suffix
2625  * @return Bool - Whether or not the extension is loaded
2626  */
2627 function wfDl( $extension, $fileName = null ) {
2628         if( extension_loaded( $extension ) ) {
2629                 return true;
2630         }
2631
2632         $canDl = false;
2633         $sapi = php_sapi_name();
2634         if( version_compare( PHP_VERSION, '5.3.0', '<' ) ||
2635                 $sapi == 'cli' || $sapi == 'cgi' || $sapi == 'embed' )
2636         {
2637                 $canDl = ( function_exists( 'dl' ) && is_callable( 'dl' )
2638                 && wfIniGetBool( 'enable_dl' ) && !wfIniGetBool( 'safe_mode' ) );
2639         }
2640
2641         if( $canDl ) {
2642                 $fileName = $fileName ? $fileName : $extension;
2643                 if( wfIsWindows() ) {
2644                         $fileName = 'php_' . $fileName;
2645                 }
2646                 wfSuppressWarnings();
2647                 dl( $fileName . '.' . PHP_SHLIB_SUFFIX );
2648                 wfRestoreWarnings();
2649         }
2650         return extension_loaded( $extension );
2651 }
2652
2653 /**
2654  * Execute a shell command, with time and memory limits mirrored from the PHP
2655  * configuration if supported.
2656  * @param $cmd String Command line, properly escaped for shell.
2657  * @param &$retval optional, will receive the program's exit code.
2658  *                 (non-zero is usually failure)
2659  * @param $environ Array optional environment variables which should be
2660  *                 added to the executed command environment.
2661  * @return collected stdout as a string (trailing newlines stripped)
2662  */
2663 function wfShellExec( $cmd, &$retval = null, $environ = array() ) {
2664         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize, $wgMaxShellTime;
2665
2666         static $disabled;
2667         if ( is_null( $disabled ) ) {
2668                 $disabled = false;
2669                 if( wfIniGetBool( 'safe_mode' ) ) {
2670                         wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
2671                         $disabled = 'safemode';
2672                 } else {
2673                         $functions = explode( ',', ini_get( 'disable_functions' ) );
2674                         $functions = array_map( 'trim', $functions );
2675                         $functions = array_map( 'strtolower', $functions );
2676                         if ( in_array( 'passthru', $functions ) ) {
2677                                 wfDebug( "passthru is in disabled_functions\n" );
2678                                 $disabled = 'passthru';
2679                         }
2680                 }
2681         }
2682         if ( $disabled ) {
2683                 $retval = 1;
2684                 return $disabled == 'safemode' ?
2685                         'Unable to run external programs in safe mode.' :
2686                         'Unable to run external programs, passthru() is disabled.';
2687         }
2688
2689         wfInitShellLocale();
2690
2691         $envcmd = '';
2692         foreach( $environ as $k => $v ) {
2693                 if ( wfIsWindows() ) {
2694                         /* Surrounding a set in quotes (method used by wfEscapeShellArg) makes the quotes themselves
2695                          * appear in the environment variable, so we must use carat escaping as documented in
2696                          * http://technet.microsoft.com/en-us/library/cc723564.aspx
2697                          * Note however that the quote isn't listed there, but is needed, and the parentheses
2698                          * are listed there but doesn't appear to need it.
2699                          */
2700                         $envcmd .= "set $k=" . preg_replace( '/([&|()<>^"])/', '^\\1', $v ) . '&& ';
2701                 } else {
2702                         /* Assume this is a POSIX shell, thus required to accept variable assignments before the command
2703                          * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_09_01
2704                          */
2705                         $envcmd .= "$k=" . escapeshellarg( $v ) . ' ';
2706                 }
2707         }
2708         $cmd = $envcmd . $cmd;
2709
2710         if ( wfIsWindows() ) {
2711                 if ( version_compare( PHP_VERSION, '5.3.0', '<' ) && /* Fixed in 5.3.0 :) */
2712                         ( version_compare( PHP_VERSION, '5.2.1', '>=' ) || php_uname( 's' ) == 'Windows NT' ) )
2713                 {
2714                         # Hack to work around PHP's flawed invocation of cmd.exe
2715                         # http://news.php.net/php.internals/21796
2716                         # Windows 9x doesn't accept any kind of quotes
2717                         $cmd = '"' . $cmd . '"';
2718                 }
2719         } elseif ( php_uname( 's' ) == 'Linux' ) {
2720                 $time = intval( $wgMaxShellTime );
2721                 $mem = intval( $wgMaxShellMemory );
2722                 $filesize = intval( $wgMaxShellFileSize );
2723
2724                 if ( $time > 0 && $mem > 0 ) {
2725                         $script = "$IP/bin/ulimit4.sh";
2726                         if ( is_executable( $script ) ) {
2727                                 $cmd = '/bin/bash ' . escapeshellarg( $script ) . " $time $mem $filesize " . escapeshellarg( $cmd );
2728                         }
2729                 }
2730         }
2731         wfDebug( "wfShellExec: $cmd\n" );
2732
2733         $retval = 1; // error by default?
2734         ob_start();
2735         passthru( $cmd, $retval );
2736         $output = ob_get_contents();
2737         ob_end_clean();
2738
2739         if ( $retval == 127 ) {
2740                 wfDebugLog( 'exec', "Possibly missing executable file: $cmd\n" );
2741         }
2742         return $output;
2743 }
2744
2745 /**
2746  * Workaround for http://bugs.php.net/bug.php?id=45132
2747  * escapeshellarg() destroys non-ASCII characters if LANG is not a UTF-8 locale
2748  */
2749 function wfInitShellLocale() {
2750         static $done = false;
2751         if ( $done ) {
2752                 return;
2753         }
2754         $done = true;
2755         global $wgShellLocale;
2756         if ( !wfIniGetBool( 'safe_mode' ) ) {
2757                 putenv( "LC_CTYPE=$wgShellLocale" );
2758                 setlocale( LC_CTYPE, $wgShellLocale );
2759         }
2760 }
2761
2762 /**
2763  * This function works like "use VERSION" in Perl, the program will die with a
2764  * backtrace if the current version of PHP is less than the version provided
2765  *
2766  * This is useful for extensions which due to their nature are not kept in sync
2767  * with releases, and might depend on other versions of PHP than the main code
2768  *
2769  * Note: PHP might die due to parsing errors in some cases before it ever
2770  *       manages to call this function, such is life
2771  *
2772  * @see perldoc -f use
2773  *
2774  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2775  *                 a float
2776  */
2777 function wfUsePHP( $req_ver ) {
2778         $php_ver = PHP_VERSION;
2779
2780         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
2781                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
2782         }
2783 }
2784
2785 /**
2786  * This function works like "use VERSION" in Perl except it checks the version
2787  * of MediaWiki, the program will die with a backtrace if the current version
2788  * of MediaWiki is less than the version provided.
2789  *
2790  * This is useful for extensions which due to their nature are not kept in sync
2791  * with releases
2792  *
2793  * @see perldoc -f use
2794  *
2795  * @param $req_ver Mixed: the version to check, can be a string, an integer, or
2796  *                 a float
2797  */
2798 function wfUseMW( $req_ver ) {
2799         global $wgVersion;
2800
2801         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
2802                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
2803         }
2804 }
2805
2806 /**
2807  * Return the final portion of a pathname.
2808  * Reimplemented because PHP5's basename() is buggy with multibyte text.
2809  * http://bugs.php.net/bug.php?id=33898
2810  *
2811  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
2812  * We'll consider it so always, as we don't want \s in our Unix paths either.
2813  *
2814  * @param $path String
2815  * @param $suffix String: to remove if present
2816  * @return String
2817  */
2818 function wfBaseName( $path, $suffix = '' ) {
2819         $encSuffix = ( $suffix == '' )
2820                 ? ''
2821                 : ( '(?:' . preg_quote( $suffix, '#' ) . ')?' );
2822         $matches = array();
2823         if( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2824                 return $matches[1];
2825         } else {
2826                 return '';
2827         }
2828 }
2829
2830 /**
2831  * Generate a relative path name to the given file.
2832  * May explode on non-matching case-insensitive paths,
2833  * funky symlinks, etc.
2834  *
2835  * @param $path String: absolute destination path including target filename
2836  * @param $from String: Absolute source path, directory only
2837  * @return String
2838  */
2839 function wfRelativePath( $path, $from ) {
2840         // Normalize mixed input on Windows...
2841         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2842         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2843
2844         // Trim trailing slashes -- fix for drive root
2845         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2846         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2847
2848         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2849         $against = explode( DIRECTORY_SEPARATOR, $from );
2850
2851         if( $pieces[0] !== $against[0] ) {
2852                 // Non-matching Windows drive letters?
2853                 // Return a full path.
2854                 return $path;
2855         }
2856
2857         // Trim off common prefix
2858         while( count( $pieces ) && count( $against )
2859                 && $pieces[0] == $against[0] ) {
2860                 array_shift( $pieces );
2861                 array_shift( $against );
2862         }
2863
2864         // relative dots to bump us to the parent
2865         while( count( $against ) ) {
2866                 array_unshift( $pieces, '..' );
2867                 array_shift( $against );
2868         }
2869
2870         array_push( $pieces, wfBaseName( $path ) );
2871
2872         return implode( DIRECTORY_SEPARATOR, $pieces );
2873 }
2874
2875 /**
2876  * Do any deferred updates and clear the list
2877  *
2878  * @param $commit String: set to 'commit' to commit after every update to
2879  *                prevent lock contention
2880  */
2881 function wfDoUpdates( $commit = '' ) {
2882         global $wgDeferredUpdateList;
2883
2884         wfProfileIn( __METHOD__ );
2885
2886         // No need to get master connections in case of empty updates array
2887         if ( !count( $wgDeferredUpdateList ) ) {
2888                 wfProfileOut( __METHOD__ );
2889                 return;
2890         }
2891
2892         $doCommit = $commit == 'commit';
2893         if ( $doCommit ) {
2894                 $dbw = wfGetDB( DB_MASTER );
2895         }
2896
2897         foreach ( $wgDeferredUpdateList as $update ) {
2898                 $update->doUpdate();
2899
2900                 if ( $doCommit && $dbw->trxLevel() ) {
2901                         $dbw->commit();
2902                 }
2903         }
2904
2905         $wgDeferredUpdateList = array();
2906         wfProfileOut( __METHOD__ );
2907 }
2908
2909 /**
2910  * Convert an arbitrarily-long digit string from one numeric base
2911  * to another, optionally zero-padding to a minimum column width.
2912  *
2913  * Supports base 2 through 36; digit values 10-36 are represented
2914  * as lowercase letters a-z. Input is case-insensitive.
2915  *
2916  * @param $input String: of digits
2917  * @param $sourceBase Integer: 2-36
2918  * @param $destBase Integer: 2-36
2919  * @param $pad Integer: 1 or greater
2920  * @param $lowercase Boolean
2921  * @return String or false on invalid input
2922  */
2923 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1, $lowercase = true ) {
2924         $input = strval( $input );
2925         if( $sourceBase < 2 ||
2926                 $sourceBase > 36 ||
2927                 $destBase < 2 ||
2928                 $destBase > 36 ||
2929                 $pad < 1 ||
2930                 $sourceBase != intval( $sourceBase ) ||
2931                 $destBase != intval( $destBase ) ||
2932                 $pad != intval( $pad ) ||
2933                 !is_string( $input ) ||
2934                 $input == '' ) {
2935                 return false;
2936         }
2937         $digitChars = ( $lowercase ) ? '0123456789abcdefghijklmnopqrstuvwxyz' : '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
2938         $inDigits = array();
2939         $outChars = '';
2940
2941         // Decode and validate input string
2942         $input = strtolower( $input );
2943         for( $i = 0; $i < strlen( $input ); $i++ ) {
2944                 $n = strpos( $digitChars, $input[$i] );
2945                 if( $n === false || $n > $sourceBase ) {
2946                         return false;
2947                 }
2948                 $inDigits[] = $n;
2949         }
2950
2951         // Iterate over the input, modulo-ing out an output digit
2952         // at a time until input is gone.
2953         while( count( $inDigits ) ) {
2954                 $work = 0;
2955                 $workDigits = array();
2956
2957                 // Long division...
2958                 foreach( $inDigits as $digit ) {
2959                         $work *= $sourceBase;
2960                         $work += $digit;
2961
2962                         if( $work < $destBase ) {
2963                                 // Gonna need to pull another digit.
2964                                 if( count( $workDigits ) ) {
2965                                         // Avoid zero-padding; this lets us find
2966                                         // the end of the input very easily when
2967                                         // length drops to zero.
2968                                         $workDigits[] = 0;
2969                                 }
2970                         } else {
2971                                 // Finally! Actual division!
2972                                 $workDigits[] = intval( $work / $destBase );
2973
2974                                 // Isn't it annoying that most programming languages
2975                                 // don't have a single divide-and-remainder operator,
2976                                 // even though the CPU implements it that way?
2977                                 $work = $work % $destBase;
2978                         }
2979                 }
2980
2981                 // All that division leaves us with a remainder,
2982                 // which is conveniently our next output digit.
2983                 $outChars .= $digitChars[$work];
2984
2985                 // And we continue!
2986                 $inDigits = $workDigits;
2987         }
2988
2989         while( strlen( $outChars ) < $pad ) {
2990                 $outChars .= '0';
2991         }
2992
2993         return strrev( $outChars );
2994 }
2995
2996 /**
2997  * Create an object with a given name and an array of construct parameters
2998  *
2999  * @param $name String
3000  * @param $p Array: parameters
3001  * @deprecated since 1.18, warnings in 1.18, removal in 1.20
3002  */
3003 function wfCreateObject( $name, $p ) {
3004         wfDeprecated( __FUNCTION__ );
3005         return MWFunction::newObj( $name, $p );
3006 }
3007
3008 function wfHttpOnlySafe() {
3009         global $wgHttpOnlyBlacklist;
3010
3011         if( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
3012                 foreach( $wgHttpOnlyBlacklist as $regex ) {
3013                         if( preg_match( $regex, $_SERVER['HTTP_USER_AGENT'] ) ) {
3014                                 return false;
3015                         }
3016                 }
3017         }
3018
3019         return true;
3020 }
3021
3022 /**
3023  * Initialise php session
3024  *
3025  * @param $sessionId Bool
3026  */
3027 function wfSetupSession( $sessionId = false ) {
3028         global $wgSessionsInMemcached, $wgCookiePath, $wgCookieDomain,
3029                         $wgCookieSecure, $wgCookieHttpOnly, $wgSessionHandler;
3030         if( $wgSessionsInMemcached ) {
3031                 if ( !defined( 'MW_COMPILED' ) ) {
3032                         global $IP;
3033                         require_once( "$IP/includes/cache/MemcachedSessions.php" );
3034                 }
3035                 session_set_save_handler( 'memsess_open', 'memsess_close', 'memsess_read',
3036                         'memsess_write', 'memsess_destroy', 'memsess_gc' );
3037
3038                 // It's necessary to register a shutdown function to call session_write_close(),
3039                 // because by the time the request shutdown function for the session module is
3040                 // called, $wgMemc has already been destroyed. Shutdown functions registered
3041                 // this way are called before object destruction.
3042                 register_shutdown_function( 'memsess_write_close' );
3043         } elseif( $wgSessionHandler && $wgSessionHandler != ini_get( 'session.save_handler' ) ) {
3044                 # Only set this if $wgSessionHandler isn't null and session.save_handler
3045                 # hasn't already been set to the desired value (that causes errors)
3046                 ini_set( 'session.save_handler', $wgSessionHandler );
3047         }
3048         $httpOnlySafe = wfHttpOnlySafe() && $wgCookieHttpOnly;
3049         wfDebugLog( 'cookie',
3050                 'session_set_cookie_params: "' . implode( '", "',
3051                         array(
3052                                 0,
3053                                 $wgCookiePath,
3054                                 $wgCookieDomain,
3055                                 $wgCookieSecure,
3056                                 $httpOnlySafe ) ) . '"' );
3057         session_set_cookie_params( 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $httpOnlySafe );
3058         session_cache_limiter( 'private, must-revalidate' );
3059         if ( $sessionId ) {
3060                 session_id( $sessionId );
3061         }
3062         wfSuppressWarnings();
3063         session_start();
3064         wfRestoreWarnings();
3065 }
3066
3067 /**
3068  * Get an object from the precompiled serialized directory
3069  *
3070  * @param $name String
3071  * @return Mixed: the variable on success, false on failure
3072  */
3073 function wfGetPrecompiledData( $name ) {
3074         global $IP;
3075
3076         $file = "$IP/serialized/$name";
3077         if ( file_exists( $file ) ) {
3078                 $blob = file_get_contents( $file );
3079                 if ( $blob ) {
3080                         return unserialize( $blob );
3081                 }
3082         }
3083         return false;
3084 }
3085
3086 /**
3087  * Get a cache key
3088  *
3089  * @param varargs
3090  * @return String
3091  */
3092 function wfMemcKey( /*... */ ) {
3093         $args = func_get_args();
3094         $key = wfWikiID() . ':' . implode( ':', $args );
3095         $key = str_replace( ' ', '_', $key );
3096         return $key;
3097 }
3098
3099 /**
3100  * Get a cache key for a foreign DB
3101  *
3102  * @param $db String
3103  * @param $prefix String
3104  * @param varargs String
3105  * @return String
3106  */
3107 function wfForeignMemcKey( $db, $prefix /*, ... */ ) {
3108         $args = array_slice( func_get_args(), 2 );
3109         if ( $prefix ) {
3110                 $key = "$db-$prefix:" . implode( ':', $args );
3111         } else {
3112                 $key = $db . ':' . implode( ':', $args );
3113         }
3114         return $key;
3115 }
3116
3117 /**
3118  * Get an ASCII string identifying this wiki
3119  * This is used as a prefix in memcached keys
3120  *
3121  * @return String
3122  */
3123 function wfWikiID() {
3124         global $wgDBprefix, $wgDBname;
3125         if ( $wgDBprefix ) {
3126                 return "$wgDBname-$wgDBprefix";
3127         } else {
3128                 return $wgDBname;
3129         }
3130 }
3131
3132 /**
3133  * Split a wiki ID into DB name and table prefix
3134  *
3135  * @param $wiki String
3136  * @param $bits String
3137  */
3138 function wfSplitWikiID( $wiki ) {
3139         $bits = explode( '-', $wiki, 2 );
3140         if ( count( $bits ) < 2 ) {
3141                 $bits[] = '';
3142         }
3143         return $bits;
3144 }
3145
3146 /**
3147  * Get a Database object.
3148  *
3149  * @param $db Integer: index of the connection to get. May be DB_MASTER for the
3150  *            master (for write queries), DB_SLAVE for potentially lagged read
3151  *            queries, or an integer >= 0 for a particular server.
3152  *
3153  * @param $groups Mixed: query groups. An array of group names that this query
3154  *                belongs to. May contain a single string if the query is only
3155  *                in one group.
3156  *
3157  * @param $wiki String: the wiki ID, or false for the current wiki
3158  *
3159  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
3160  * will always return the same object, unless the underlying connection or load
3161  * balancer is manually destroyed.
3162  *
3163  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
3164  * updater to ensure that a proper database is being updated.
3165  *
3166  * @return DatabaseBase
3167  */
3168 function &wfGetDB( $db, $groups = array(), $wiki = false ) {
3169         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
3170 }
3171
3172 /**
3173  * Get a load balancer object.
3174  *
3175  * @param $wiki String: wiki ID, or false for the current wiki
3176  * @return LoadBalancer
3177  */
3178 function wfGetLB( $wiki = false ) {
3179         return wfGetLBFactory()->getMainLB( $wiki );
3180 }
3181
3182 /**
3183  * Get the load balancer factory object
3184  *
3185  * @return LBFactory
3186  */
3187 function &wfGetLBFactory() {
3188         return LBFactory::singleton();
3189 }
3190
3191 /**
3192  * Find a file.
3193  * Shortcut for RepoGroup::singleton()->findFile()
3194  *
3195  * @param $title String or Title object
3196  * @param $options Associative array of options:
3197  *     time:           requested time for an archived image, or false for the
3198  *                     current version. An image object will be returned which was
3199  *                     created at the specified time.
3200  *
3201  *     ignoreRedirect: If true, do not follow file redirects
3202  *
3203  *     private:        If true, return restricted (deleted) files if the current
3204  *                     user is allowed to view them. Otherwise, such files will not
3205  *                     be found.
3206  *
3207  *     bypassCache:    If true, do not use the process-local cache of File objects
3208  *
3209  * @return File, or false if the file does not exist
3210  */
3211 function wfFindFile( $title, $options = array() ) {
3212         return RepoGroup::singleton()->findFile( $title, $options );
3213 }
3214
3215 /**
3216  * Get an object referring to a locally registered file.
3217  * Returns a valid placeholder object if the file does not exist.
3218  *
3219  * @param $title Title or String
3220  * @return File, or null if passed an invalid Title
3221  */
3222 function wfLocalFile( $title ) {
3223         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
3224 }
3225
3226 /**
3227  * Stream a file to the browser. Back-compat alias for StreamFile::stream()
3228  * @deprecated since 1.19
3229  */
3230 function wfStreamFile( $fname, $headers = array() ) {
3231         StreamFile::stream( $fname, $headers );
3232 }
3233
3234 /**
3235  * Should low-performance queries be disabled?
3236  *
3237  * @return Boolean
3238  * @codeCoverageIgnore
3239  */
3240 function wfQueriesMustScale() {
3241         global $wgMiserMode;
3242         return $wgMiserMode
3243                 || ( SiteStats::pages() > 100000
3244                 && SiteStats::edits() > 1000000
3245                 && SiteStats::users() > 10000 );
3246 }
3247
3248 /**
3249  * Get the path to a specified script file, respecting file
3250  * extensions; this is a wrapper around $wgScriptExtension etc.
3251  *
3252  * @param $script String: script filename, sans extension
3253  * @return String
3254  */
3255 function wfScript( $script = 'index' ) {
3256         global $wgScriptPath, $wgScriptExtension;
3257         return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
3258 }
3259
3260 /**
3261  * Get the script URL.
3262  *
3263  * @return script URL
3264  */
3265 function wfGetScriptUrl() {
3266         if( isset( $_SERVER['SCRIPT_NAME'] ) ) {
3267                 #
3268                 # as it was called, minus the query string.
3269                 #
3270                 # Some sites use Apache rewrite rules to handle subdomains,
3271                 # and have PHP set up in a weird way that causes PHP_SELF
3272                 # to contain the rewritten URL instead of the one that the
3273                 # outside world sees.
3274                 #
3275                 # If in this mode, use SCRIPT_URL instead, which mod_rewrite
3276                 # provides containing the "before" URL.
3277                 return $_SERVER['SCRIPT_NAME'];
3278         } else {
3279                 return $_SERVER['URL'];
3280         }
3281 }
3282
3283 /**
3284  * Convenience function converts boolean values into "true"
3285  * or "false" (string) values
3286  *
3287  * @param $value Boolean
3288  * @return String
3289  */
3290 function wfBoolToStr( $value ) {
3291         return $value ? 'true' : 'false';
3292 }
3293
3294 /**
3295  * Load an extension messages file
3296  *
3297  * @deprecated since 1.16, warnings in 1.18, remove in 1.20
3298  * @codeCoverageIgnore
3299  */
3300 function wfLoadExtensionMessages() {
3301         wfDeprecated( __FUNCTION__ );
3302 }
3303
3304 /**
3305  * Get a platform-independent path to the null file, e.g. /dev/null
3306  *
3307  * @return string
3308  */
3309 function wfGetNull() {
3310         return wfIsWindows()
3311                 ? 'NUL'
3312                 : '/dev/null';
3313 }
3314
3315 /**
3316  * Throws a warning that $function is deprecated
3317  *
3318  * @param $function String
3319  * @return null
3320  */
3321 function wfDeprecated( $function ) {
3322         static $functionsWarned = array();
3323         if ( !isset( $functionsWarned[$function] ) ) {
3324                 $functionsWarned[$function] = true;
3325                 wfWarn( "Use of $function is deprecated.", 2 );
3326         }
3327 }
3328
3329 /**
3330  * Send a warning either to the debug log or in a PHP error depending on
3331  * $wgDevelopmentWarnings
3332  *
3333  * @param $msg String: message to send
3334  * @param $callerOffset Integer: number of items to go back in the backtrace to
3335  *        find the correct caller (1 = function calling wfWarn, ...)
3336  * @param $level Integer: PHP error level; only used when $wgDevelopmentWarnings
3337  *        is true
3338  */
3339 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
3340         global $wgDevelopmentWarnings;
3341
3342         $callers = wfDebugBacktrace();
3343         if ( isset( $callers[$callerOffset + 1] ) ) {
3344                 $callerfunc = $callers[$callerOffset + 1];
3345                 $callerfile = $callers[$callerOffset];
3346                 if ( isset( $callerfile['file'] ) && isset( $callerfile['line'] ) ) {
3347                         $file = $callerfile['file'] . ' at line ' . $callerfile['line'];
3348                 } else {
3349                         $file = '(internal function)';
3350                 }
3351                 $func = '';
3352                 if ( isset( $callerfunc['class'] ) ) {
3353                         $func .= $callerfunc['class'] . '::';
3354                 }
3355                 if ( isset( $callerfunc['function'] ) ) {
3356                         $func .= $callerfunc['function'];
3357                 }
3358                 $msg .= " [Called from $func in $file]";
3359         }
3360
3361         if ( $wgDevelopmentWarnings ) {
3362                 trigger_error( $msg, $level );
3363         } else {
3364                 wfDebug( "$msg\n" );
3365         }
3366 }
3367
3368 /**
3369  * Modern version of wfWaitForSlaves(). Instead of looking at replication lag
3370  * and waiting for it to go down, this waits for the slaves to catch up to the
3371  * master position. Use this when updating very large numbers of rows, as
3372  * in maintenance scripts, to avoid causing too much lag.  Of course, this is
3373  * a no-op if there are no slaves.
3374  *
3375  * @param $maxLag Integer (deprecated)
3376  * @param $wiki mixed Wiki identifier accepted by wfGetLB
3377  * @return null
3378  */
3379 function wfWaitForSlaves( $maxLag = false, $wiki = false ) {
3380         $lb = wfGetLB( $wiki );
3381         // bug 27975 - Don't try to wait for slaves if there are none
3382         // Prevents permission error when getting master position
3383         if ( $lb->getServerCount() > 1 ) {
3384                 $dbw = $lb->getConnection( DB_MASTER );
3385                 $pos = $dbw->getMasterPos();
3386                 $lb->waitForAll( $pos );
3387         }
3388 }
3389
3390 /**
3391  * Used to be used for outputting text in the installer/updater
3392  * @deprecated since 1.18, warnings in 1.18, remove in 1.20
3393  */
3394 function wfOut( $s ) {
3395         wfDeprecated( __METHOD__ );
3396         global $wgCommandLineMode;
3397         if ( $wgCommandLineMode ) {
3398                 echo $s;
3399         } else {
3400                 echo htmlspecialchars( $s );
3401         }
3402         flush();
3403 }
3404
3405 /**
3406  * Count down from $n to zero on the terminal, with a one-second pause
3407  * between showing each number. For use in command-line scripts.
3408  * @codeCoverageIgnore
3409  */
3410 function wfCountDown( $n ) {
3411         for ( $i = $n; $i >= 0; $i-- ) {
3412                 if ( $i != $n ) {
3413                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3414                 }
3415                 echo $i;
3416                 flush();
3417                 if ( $i ) {
3418                         sleep( 1 );
3419                 }
3420         }
3421         echo "\n";
3422 }
3423
3424 /**
3425  * Generate a random 32-character hexadecimal token.
3426  * @param $salt Mixed: some sort of salt, if necessary, to add to random
3427  *              characters before hashing.
3428  * @return string
3429  * @codeCoverageIgnore
3430  */
3431 function wfGenerateToken( $salt = '' ) {
3432         $salt = serialize( $salt );
3433         return md5( mt_rand( 0, 0x7fffffff ) . $salt );
3434 }
3435
3436 /**
3437  * Replace all invalid characters with -
3438  *
3439  * @param $name Mixed: filename to process
3440  * @return String
3441  */
3442 function wfStripIllegalFilenameChars( $name ) {
3443         global $wgIllegalFileChars;
3444         $name = wfBaseName( $name );
3445         $name = preg_replace(
3446                 "/[^" . Title::legalChars() . "]" .
3447                         ( $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '' ) .
3448                         "/",
3449                 '-',
3450                 $name
3451         );
3452         return $name;
3453 }
3454
3455 /**
3456  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit;
3457  *
3458  * @return Integer value memory was set to.
3459  */
3460 function wfMemoryLimit() {
3461         global $wgMemoryLimit;
3462         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3463         if( $memlimit != -1 ) {
3464                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3465                 if( $conflimit == -1 ) {
3466                         wfDebug( "Removing PHP's memory limit\n" );
3467                         wfSuppressWarnings();
3468                         ini_set( 'memory_limit', $conflimit );
3469                         wfRestoreWarnings();
3470                         return $conflimit;
3471                 } elseif ( $conflimit > $memlimit ) {
3472                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3473                         wfSuppressWarnings();
3474                         ini_set( 'memory_limit', $conflimit );
3475                         wfRestoreWarnings();
3476                         return $conflimit;
3477                 }
3478         }
3479         return $memlimit;
3480 }
3481
3482 /**
3483  * Converts shorthand byte notation to integer form
3484  *
3485  * @param $string String
3486  * @return Integer
3487  */
3488 function wfShorthandToInteger( $string = '' ) {
3489         $string = trim( $string );
3490         if( $string === '' ) {
3491                 return -1;
3492         }
3493         $last = $string[strlen( $string ) - 1];
3494         $val = intval( $string );
3495         switch( $last ) {
3496                 case 'g':
3497                 case 'G':
3498                         $val *= 1024;
3499                         // break intentionally missing
3500                 case 'm':
3501                 case 'M':
3502                         $val *= 1024;
3503                         // break intentionally missing
3504                 case 'k':
3505                 case 'K':
3506                         $val *= 1024;
3507         }
3508
3509         return $val;
3510 }
3511
3512 /**
3513  * Get the normalised IETF language tag
3514  * See unit test for examples.
3515  *
3516  * @param $code String: The language code.
3517  * @return $langCode String: The language code which complying with BCP 47 standards.
3518  */
3519 function wfBCP47( $code ) {
3520         $codeSegment = explode( '-', $code );
3521         $codeBCP = array();
3522         foreach ( $codeSegment as $segNo => $seg ) {
3523                 if ( count( $codeSegment ) > 0 ) {
3524                         // when previous segment is x, it is a private segment and should be lc
3525                         if( $segNo > 0 && strtolower( $codeSegment[($segNo - 1)] ) == 'x') {
3526                                 $codeBCP[$segNo] = strtolower( $seg );
3527                         // ISO 3166 country code
3528                         } elseif ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3529                                 $codeBCP[$segNo] = strtoupper( $seg );
3530                         // ISO 15924 script code
3531                         } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3532                                 $codeBCP[$segNo] = ucfirst( strtolower( $seg ) );
3533                         // Use lowercase for other cases
3534                         } else {
3535                                 $codeBCP[$segNo] = strtolower( $seg );
3536                         }
3537                 } else {
3538                 // Use lowercase for single segment
3539                         $codeBCP[$segNo] = strtolower( $seg );
3540                 }
3541         }
3542         $langCode = implode( '-', $codeBCP );
3543         return $langCode;
3544 }
3545
3546 /**
3547  * Get a cache object.
3548  *
3549  * @param $inputType integer Cache type, one the the CACHE_* constants.
3550  * @return BagOStuff
3551  */
3552 function wfGetCache( $inputType ) {
3553         return ObjectCache::getInstance( $inputType );
3554 }
3555
3556 /**
3557  * Get the main cache object
3558  *
3559  * @return BagOStuff
3560  */
3561 function wfGetMainCache() {
3562         global $wgMainCacheType;
3563         return ObjectCache::getInstance( $wgMainCacheType );
3564 }
3565
3566 /**
3567  * Get the cache object used by the message cache
3568  *
3569  * @return BagOStuff
3570  */
3571 function wfGetMessageCacheStorage() {
3572         global $wgMessageCacheType;
3573         return ObjectCache::getInstance( $wgMessageCacheType );
3574 }
3575
3576 /**
3577  * Get the cache object used by the parser cache
3578  *
3579  * @return BagOStuff
3580  */
3581 function wfGetParserCacheStorage() {
3582         global $wgParserCacheType;
3583         return ObjectCache::getInstance( $wgParserCacheType );
3584 }
3585
3586 /**
3587  * Call hook functions defined in $wgHooks
3588  *
3589  * @param $event String: event name
3590  * @param $args Array: parameters passed to hook functions
3591  * @return Boolean
3592  */
3593 function wfRunHooks( $event, $args = array() ) {
3594         return Hooks::run( $event, $args );
3595 }