includes/GlobalFunctions.php

   1 <?php
   2 /**
   3  * Global functions used everywhere.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  */
  22
  23 if ( !defined( 'MEDIAWIKI' ) ) {
  24         die( "This file is part of MediaWiki, it is not a valid entry point" );
  25 }
  26
  27 use Liuggio\StatsdClient\StatsdClient;
  28 use Liuggio\StatsdClient\Sender\SocketSender;
  29 use MediaWiki\Logger\LoggerFactory;
  30
  31 // Hide compatibility functions from Doxygen
  32 /// @cond
  33
  34 /**
  35  * Compatibility functions
  36  *
  37  * We support PHP 5.3.3 and up.
  38  * Re-implementations of newer functions or functions in non-standard
  39  * PHP extensions may be included here.
  40  */
  41
  42 if ( !function_exists( 'mb_substr' ) ) {
  43         /**
  44          * @codeCoverageIgnore
  45          * @see Fallback::mb_substr
  46          * @return string
  47          */
  48         function mb_substr( $str, $start, $count = 'end' ) {
  49                 return Fallback::mb_substr( $str, $start, $count );
  50         }
  51
  52         /**
  53          * @codeCoverageIgnore
  54          * @see Fallback::mb_substr_split_unicode
  55          * @return int
  56          */
  57         function mb_substr_split_unicode( $str, $splitPos ) {
  58                 return Fallback::mb_substr_split_unicode( $str, $splitPos );
  59         }
  60 }
  61
  62 if ( !function_exists( 'mb_strlen' ) ) {
  63         /**
  64          * @codeCoverageIgnore
  65          * @see Fallback::mb_strlen
  66          * @return int
  67          */
  68         function mb_strlen( $str, $enc = '' ) {
  69                 return Fallback::mb_strlen( $str, $enc );
  70         }
  71 }
  72
  73 if ( !function_exists( 'mb_strpos' ) ) {
  74         /**
  75          * @codeCoverageIgnore
  76          * @see Fallback::mb_strpos
  77          * @return int
  78          */
  79         function mb_strpos( $haystack, $needle, $offset = 0, $encoding = '' ) {
  80                 return Fallback::mb_strpos( $haystack, $needle, $offset, $encoding );
  81         }
  82 }
  83
  84 if ( !function_exists( 'mb_strrpos' ) ) {
  85         /**
  86          * @codeCoverageIgnore
  87          * @see Fallback::mb_strrpos
  88          * @return int
  89          */
  90         function mb_strrpos( $haystack, $needle, $offset = 0, $encoding = '' ) {
  91                 return Fallback::mb_strrpos( $haystack, $needle, $offset, $encoding );
  92         }
  93 }
  94
  95 // gzdecode function only exists in PHP >= 5.4.0
  96 // http://php.net/gzdecode
  97 if ( !function_exists( 'gzdecode' ) ) {
  98         /**
  99          * @codeCoverageIgnore
 100          * @param string $data
 101          * @return string
 102          */
 103         function gzdecode( $data ) {
 104                 return gzinflate( substr( $data, 10, -8 ) );
 105         }
 106 }
 107
 108 // hash_equals function only exists in PHP >= 5.6.0
 109 // http://php.net/hash_equals
 110 if ( !function_exists( 'hash_equals' ) ) {
 111         /**
 112          * Check whether a user-provided string is equal to a fixed-length secret string
 113          * without revealing bytes of the secret string through timing differences.
 114          *
 115          * The usual way to compare strings (PHP's === operator or the underlying memcmp()
 116          * function in C) is to compare corresponding bytes and stop at the first difference,
 117          * which would take longer for a partial match than for a complete mismatch. This
 118          * is not secure when one of the strings (e.g. an HMAC or token) must remain secret
 119          * and the other may come from an attacker. Statistical analysis of timing measurements
 120          * over many requests may allow the attacker to guess the string's bytes one at a time
 121          * (and check his guesses) even if the timing differences are extremely small.
 122          *
 123          * When making such a security-sensitive comparison, it is essential that the sequence
 124          * in which instructions are executed and memory locations are accessed not depend on
 125          * the secret string's value. HOWEVER, for simplicity, we do not attempt to minimize
 126          * the inevitable leakage of the string's length. That is generally known anyway as
 127          * a chararacteristic of the hash function used to compute the secret value.
 128          *
 129          * Longer explanation: http://www.emerose.com/timing-attacks-explained
 130          *
 131          * @codeCoverageIgnore
 132          * @param string $known_string Fixed-length secret string to compare against
 133          * @param string $user_string User-provided string
 134          * @return bool True if the strings are the same, false otherwise
 135          */
 136         function hash_equals( $known_string, $user_string ) {
 137                 // Strict type checking as in PHP's native implementation
 138                 if ( !is_string( $known_string ) ) {
 139                         trigger_error( 'hash_equals(): Expected known_string to be a string, ' .
 140                                 gettype( $known_string ) . ' given', E_USER_WARNING );
 141
 142                         return false;
 143                 }
 144
 145                 if ( !is_string( $user_string ) ) {
 146                         trigger_error( 'hash_equals(): Expected user_string to be a string, ' .
 147                                 gettype( $user_string ) . ' given', E_USER_WARNING );
 148
 149                         return false;
 150                 }
 151
 152                 $known_string_len = strlen( $known_string );
 153                 if ( $known_string_len !== strlen( $user_string ) ) {
 154                         return false;
 155                 }
 156
 157                 $result = 0;
 158                 for ( $i = 0; $i < $known_string_len; $i++ ) {
 159                         $result |= ord( $known_string[$i] ) ^ ord( $user_string[$i] );
 160                 }
 161
 162                 return ( $result === 0 );
 163         }
 164 }
 165 /// @endcond
 166
 167 /**
 168  * Load an extension
 169  *
 170  * This queues an extension to be loaded through
 171  * the ExtensionRegistry system.
 172  *
 173  * @param string $ext Name of the extension to load
 174  * @param string|null $path Absolute path of where to find the extension.json file
 175  */
 176 function wfLoadExtension( $ext, $path = null ) {
 177         if ( !$path ) {
 178                 global $wgExtensionDirectory;
 179                 $path = "$wgExtensionDirectory/$ext/extension.json";
 180         }
 181         ExtensionRegistry::getInstance()->queue( $path );
 182 }
 183
 184 /**
 185  * Load multiple extensions at once
 186  *
 187  * Same as wfLoadExtension, but more efficient if you
 188  * are loading multiple extensions.
 189  *
 190  * If you want to specify custom paths, you should interact with
 191  * ExtensionRegistry directly.
 192  *
 193  * @see wfLoadExtension
 194  * @param string[] $exts Array of extension names to load
 195  */
 196 function wfLoadExtensions( array $exts ) {
 197         global $wgExtensionDirectory;
 198         $registry = ExtensionRegistry::getInstance();
 199         foreach ( $exts as $ext ) {
 200                 $registry->queue( "$wgExtensionDirectory/$ext/extension.json" );
 201         }
 202 }
 203
 204 /**
 205  * Load a skin
 206  *
 207  * @see wfLoadExtension
 208  * @param string $skin Name of the extension to load
 209  * @param string|null $path Absolute path of where to find the skin.json file
 210  */
 211 function wfLoadSkin( $skin, $path = null ) {
 212         if ( !$path ) {
 213                 global $wgStyleDirectory;
 214                 $path = "$wgStyleDirectory/$skin/skin.json";
 215         }
 216         ExtensionRegistry::getInstance()->queue( $path );
 217 }
 218
 219 /**
 220  * Load multiple skins at once
 221  *
 222  * @see wfLoadExtensions
 223  * @param string[] $skins Array of extension names to load
 224  */
 225 function wfLoadSkins( array $skins ) {
 226         global $wgStyleDirectory;
 227         $registry = ExtensionRegistry::getInstance();
 228         foreach ( $skins as $skin ) {
 229                 $registry->queue( "$wgStyleDirectory/$skin/skin.json" );
 230         }
 231 }
 232
 233 /**
 234  * Like array_diff( $a, $b ) except that it works with two-dimensional arrays.
 235  * @param array $a
 236  * @param array $b
 237  * @return array
 238  */
 239 function wfArrayDiff2( $a, $b ) {
 240         return array_udiff( $a, $b, 'wfArrayDiff2_cmp' );
 241 }
 242
 243 /**
 244  * @param array|string $a
 245  * @param array|string $b
 246  * @return int
 247  */
 248 function wfArrayDiff2_cmp( $a, $b ) {
 249         if ( is_string( $a ) && is_string( $b ) ) {
 250                 return strcmp( $a, $b );
 251         } elseif ( count( $a ) !== count( $b ) ) {
 252                 return count( $a ) < count( $b ) ? -1 : 1;
 253         } else {
 254                 reset( $a );
 255                 reset( $b );
 256                 while ( ( list( , $valueA ) = each( $a ) ) && ( list( , $valueB ) = each( $b ) ) ) {
 257                         $cmp = strcmp( $valueA, $valueB );
 258                         if ( $cmp !== 0 ) {
 259                                 return $cmp;
 260                         }
 261                 }
 262                 return 0;
 263         }
 264 }
 265
 266 /**
 267  * Appends to second array if $value differs from that in $default
 268  *
 269  * @param string|int $key
 270  * @param mixed $value
 271  * @param mixed $default
 272  * @param array $changed Array to alter
 273  * @throws MWException
 274  */
 275 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
 276         if ( is_null( $changed ) ) {
 277                 throw new MWException( 'GlobalFunctions::wfAppendToArrayIfNotDefault got null' );
 278         }
 279         if ( $default[$key] !== $value ) {
 280                 $changed[$key] = $value;
 281         }
 282 }
 283
 284 /**
 285  * Merge arrays in the style of getUserPermissionsErrors, with duplicate removal
 286  * e.g.
 287  *      wfMergeErrorArrays(
 288  *              array( array( 'x' ) ),
 289  *              array( array( 'x', '2' ) ),
 290  *              array( array( 'x' ) ),
 291  *              array( array( 'y' ) )
 292  *      );
 293  * returns:
 294  *              array(
 295  *              array( 'x', '2' ),
 296  *              array( 'x' ),
 297  *              array( 'y' )
 298  *      )
 299  *
 300  * @param array $array1,...
 301  * @return array
 302  */
 303 function wfMergeErrorArrays( /*...*/ ) {
 304         $args = func_get_args();
 305         $out = array();
 306         foreach ( $args as $errors ) {
 307                 foreach ( $errors as $params ) {
 308                         # @todo FIXME: Sometimes get nested arrays for $params,
 309                         # which leads to E_NOTICEs
 310                         $spec = implode( "\t", $params );
 311                         $out[$spec] = $params;
 312                 }
 313         }
 314         return array_values( $out );
 315 }
 316
 317 /**
 318  * Insert array into another array after the specified *KEY*
 319  *
 320  * @param array $array The array.
 321  * @param array $insert The array to insert.
 322  * @param mixed $after The key to insert after
 323  * @return array
 324  */
 325 function wfArrayInsertAfter( array $array, array $insert, $after ) {
 326         // Find the offset of the element to insert after.
 327         $keys = array_keys( $array );
 328         $offsetByKey = array_flip( $keys );
 329
 330         $offset = $offsetByKey[$after];
 331
 332         // Insert at the specified offset
 333         $before = array_slice( $array, 0, $offset + 1, true );
 334         $after = array_slice( $array, $offset + 1, count( $array ) - $offset, true );
 335
 336         $output = $before + $insert + $after;
 337
 338         return $output;
 339 }
 340
 341 /**
 342  * Recursively converts the parameter (an object) to an array with the same data
 343  *
 344  * @param object|array $objOrArray
 345  * @param bool $recursive
 346  * @return array
 347  */
 348 function wfObjectToArray( $objOrArray, $recursive = true ) {
 349         $array = array();
 350         if ( is_object( $objOrArray ) ) {
 351                 $objOrArray = get_object_vars( $objOrArray );
 352         }
 353         foreach ( $objOrArray as $key => $value ) {
 354                 if ( $recursive && ( is_object( $value ) || is_array( $value ) ) ) {
 355                         $value = wfObjectToArray( $value );
 356                 }
 357
 358                 $array[$key] = $value;
 359         }
 360
 361         return $array;
 362 }
 363
 364 /**
 365  * Get a random decimal value between 0 and 1, in a way
 366  * not likely to give duplicate values for any realistic
 367  * number of articles.
 368  *
 369  * @return string
 370  */
 371 function wfRandom() {
 372         # The maximum random value is "only" 2^31-1, so get two random
 373         # values to reduce the chance of dupes
 374         $max = mt_getrandmax() + 1;
 375         $rand = number_format( ( mt_rand() * $max + mt_rand() ) / $max / $max, 12, '.', '' );
 376
 377         return $rand;
 378 }
 379
 380 /**
 381  * Get a random string containing a number of pseudo-random hex
 382  * characters.
 383  * @note This is not secure, if you are trying to generate some sort
 384  *       of token please use MWCryptRand instead.
 385  *
 386  * @param int $length The length of the string to generate
 387  * @return string
 388  * @since 1.20
 389  */
 390 function wfRandomString( $length = 32 ) {
 391         $str = '';
 392         for ( $n = 0; $n < $length; $n += 7 ) {
 393                 $str .= sprintf( '%07x', mt_rand() & 0xfffffff );
 394         }
 395         return substr( $str, 0, $length );
 396 }
 397
 398 /**
 399  * We want some things to be included as literal characters in our title URLs
 400  * for prettiness, which urlencode encodes by default.  According to RFC 1738,
 401  * all of the following should be safe:
 402  *
 403  * ;:@&=$-_.+!*'(),
 404  *
 405  * But + is not safe because it's used to indicate a space; &= are only safe in
 406  * paths and not in queries (and we don't distinguish here); ' seems kind of
 407  * scary; and urlencode() doesn't touch -_. to begin with.  Plus, although /
 408  * is reserved, we don't care.  So the list we unescape is:
 409  *
 410  * ;:@$!*(),/
 411  *
 412  * However, IIS7 redirects fail when the url contains a colon (Bug 22709),
 413  * so no fancy : for IIS7.
 414  *
 415  * %2F in the page titles seems to fatally break for some reason.
 416  *
 417  * @param string $s
 418  * @return string
 419  */
 420 function wfUrlencode( $s ) {
 421         static $needle;
 422
 423         if ( is_null( $s ) ) {
 424                 $needle = null;
 425                 return '';
 426         }
 427
 428         if ( is_null( $needle ) ) {
 429                 $needle = array( '%3B', '%40', '%24', '%21', '%2A', '%28', '%29', '%2C', '%2F' );
 430                 if ( !isset( $_SERVER['SERVER_SOFTWARE'] ) ||
 431                         ( strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/7' ) === false )
 432                 ) {
 433                         $needle[] = '%3A';
 434                 }
 435         }
 436
 437         $s = urlencode( $s );
 438         $s = str_ireplace(
 439                 $needle,
 440                 array( ';', '@', '$', '!', '*', '(', ')', ',', '/', ':' ),
 441                 $s
 442         );
 443
 444         return $s;
 445 }
 446
 447 /**
 448  * This function takes two arrays as input, and returns a CGI-style string, e.g.
 449  * "days=7&limit=100". Options in the first array override options in the second.
 450  * Options set to null or false will not be output.
 451  *
 452  * @param array $array1 ( String|Array )
 453  * @param array $array2 ( String|Array )
 454  * @param string $prefix
 455  * @return string
 456  */
 457 function wfArrayToCgi( $array1, $array2 = null, $prefix = '' ) {
 458         if ( !is_null( $array2 ) ) {
 459                 $array1 = $array1 + $array2;
 460         }
 461
 462         $cgi = '';
 463         foreach ( $array1 as $key => $value ) {
 464                 if ( !is_null( $value ) && $value !== false ) {
 465                         if ( $cgi != '' ) {
 466                                 $cgi .= '&';
 467                         }
 468                         if ( $prefix !== '' ) {
 469                                 $key = $prefix . "[$key]";
 470                         }
 471                         if ( is_array( $value ) ) {
 472                                 $firstTime = true;
 473                                 foreach ( $value as $k => $v ) {
 474                                         $cgi .= $firstTime ? '' : '&';
 475                                         if ( is_array( $v ) ) {
 476                                                 $cgi .= wfArrayToCgi( $v, null, $key . "[$k]" );
 477                                         } else {
 478                                                 $cgi .= urlencode( $key . "[$k]" ) . '=' . urlencode( $v );
 479                                         }
 480                                         $firstTime = false;
 481                                 }
 482                         } else {
 483                                 if ( is_object( $value ) ) {
 484                                         $value = $value->__toString();
 485                                 }
 486                                 $cgi .= urlencode( $key ) . '=' . urlencode( $value );
 487                         }
 488                 }
 489         }
 490         return $cgi;
 491 }
 492
 493 /**
 494  * This is the logical opposite of wfArrayToCgi(): it accepts a query string as
 495  * its argument and returns the same string in array form.  This allows compatibility
 496  * with legacy functions that accept raw query strings instead of nice
 497  * arrays.  Of course, keys and values are urldecode()d.
 498  *
 499  * @param string $query Query string
 500  * @return string[] Array version of input
 501  */
 502 function wfCgiToArray( $query ) {
 503         if ( isset( $query[0] ) && $query[0] == '?' ) {
 504                 $query = substr( $query, 1 );
 505         }
 506         $bits = explode( '&', $query );
 507         $ret = array();
 508         foreach ( $bits as $bit ) {
 509                 if ( $bit === '' ) {
 510                         continue;
 511                 }
 512                 if ( strpos( $bit, '=' ) === false ) {
 513                         // Pieces like &qwerty become 'qwerty' => '' (at least this is what php does)
 514                         $key = $bit;
 515                         $value = '';
 516                 } else {
 517                         list( $key, $value ) = explode( '=', $bit );
 518                 }
 519                 $key = urldecode( $key );
 520                 $value = urldecode( $value );
 521                 if ( strpos( $key, '[' ) !== false ) {
 522                         $keys = array_reverse( explode( '[', $key ) );
 523                         $key = array_pop( $keys );
 524                         $temp = $value;
 525                         foreach ( $keys as $k ) {
 526                                 $k = substr( $k, 0, -1 );
 527                                 $temp = array( $k => $temp );
 528                         }
 529                         if ( isset( $ret[$key] ) ) {
 530                                 $ret[$key] = array_merge( $ret[$key], $temp );
 531                         } else {
 532                                 $ret[$key] = $temp;
 533                         }
 534                 } else {
 535                         $ret[$key] = $value;
 536                 }
 537         }
 538         return $ret;
 539 }
 540
 541 /**
 542  * Append a query string to an existing URL, which may or may not already
 543  * have query string parameters already. If so, they will be combined.
 544  *
 545  * @param string $url
 546  * @param string|string[] $query String or associative array
 547  * @return string
 548  */
 549 function wfAppendQuery( $url, $query ) {
 550         if ( is_array( $query ) ) {
 551                 $query = wfArrayToCgi( $query );
 552         }
 553         if ( $query != '' ) {
 554                 if ( false === strpos( $url, '?' ) ) {
 555                         $url .= '?';
 556                 } else {
 557                         $url .= '&';
 558                 }
 559                 $url .= $query;
 560         }
 561         return $url;
 562 }
 563
 564 /**
 565  * Expand a potentially local URL to a fully-qualified URL. Assumes $wgServer
 566  * is correct.
 567  *
 568  * The meaning of the PROTO_* constants is as follows:
 569  * PROTO_HTTP: Output a URL starting with http://
 570  * PROTO_HTTPS: Output a URL starting with https://
 571  * PROTO_RELATIVE: Output a URL starting with // (protocol-relative URL)
 572  * PROTO_CURRENT: Output a URL starting with either http:// or https:// , depending
 573  *    on which protocol was used for the current incoming request
 574  * PROTO_CANONICAL: For URLs without a domain, like /w/index.php , use $wgCanonicalServer.
 575  *    For protocol-relative URLs, use the protocol of $wgCanonicalServer
 576  * PROTO_INTERNAL: Like PROTO_CANONICAL, but uses $wgInternalServer instead of $wgCanonicalServer
 577  *
 578  * @todo this won't work with current-path-relative URLs
 579  * like "subdir/foo.html", etc.
 580  *
 581  * @param string $url Either fully-qualified or a local path + query
 582  * @param string $defaultProto One of the PROTO_* constants. Determines the
 583  *    protocol to use if $url or $wgServer is protocol-relative
 584  * @return string Fully-qualified URL, current-path-relative URL or false if
 585  *    no valid URL can be constructed
 586  */
 587 function wfExpandUrl( $url, $defaultProto = PROTO_CURRENT ) {
 588         global $wgServer, $wgCanonicalServer, $wgInternalServer, $wgRequest,
 589                 $wgHttpsPort;
 590         if ( $defaultProto === PROTO_CANONICAL ) {
 591                 $serverUrl = $wgCanonicalServer;
 592         } elseif ( $defaultProto === PROTO_INTERNAL && $wgInternalServer !== false ) {
 593                 // Make $wgInternalServer fall back to $wgServer if not set
 594                 $serverUrl = $wgInternalServer;
 595         } else {
 596                 $serverUrl = $wgServer;
 597                 if ( $defaultProto === PROTO_CURRENT ) {
 598                         $defaultProto = $wgRequest->getProtocol() . '://';
 599                 }
 600         }
 601
 602         // Analyze $serverUrl to obtain its protocol
 603         $bits = wfParseUrl( $serverUrl );
 604         $serverHasProto = $bits && $bits['scheme'] != '';
 605
 606         if ( $defaultProto === PROTO_CANONICAL || $defaultProto === PROTO_INTERNAL ) {
 607                 if ( $serverHasProto ) {
 608                         $defaultProto = $bits['scheme'] . '://';
 609                 } else {
 610                         // $wgCanonicalServer or $wgInternalServer doesn't have a protocol.
 611                         // This really isn't supposed to happen. Fall back to HTTP in this
 612                         // ridiculous case.
 613                         $defaultProto = PROTO_HTTP;
 614                 }
 615         }
 616
 617         $defaultProtoWithoutSlashes = substr( $defaultProto, 0, -2 );
 618
 619         if ( substr( $url, 0, 2 ) == '//' ) {
 620                 $url = $defaultProtoWithoutSlashes . $url;
 621         } elseif ( substr( $url, 0, 1 ) == '/' ) {
 622                 // If $serverUrl is protocol-relative, prepend $defaultProtoWithoutSlashes,
 623                 // otherwise leave it alone.
 624                 $url = ( $serverHasProto ? '' : $defaultProtoWithoutSlashes ) . $serverUrl . $url;
 625         }
 626
 627         $bits = wfParseUrl( $url );
 628
 629         // ensure proper port for HTTPS arrives in URL
 630         // https://bugzilla.wikimedia.org/show_bug.cgi?id=65184
 631         if ( $defaultProto === PROTO_HTTPS && $wgHttpsPort != 443 ) {
 632                 $bits['port'] = $wgHttpsPort;
 633         }
 634
 635         if ( $bits && isset( $bits['path'] ) ) {
 636                 $bits['path'] = wfRemoveDotSegments( $bits['path'] );
 637                 return wfAssembleUrl( $bits );
 638         } elseif ( $bits ) {
 639                 # No path to expand
 640                 return $url;
 641         } elseif ( substr( $url, 0, 1 ) != '/' ) {
 642                 # URL is a relative path
 643                 return wfRemoveDotSegments( $url );
 644         }
 645
 646         # Expanded URL is not valid.
 647         return false;
 648 }
 649
 650 /**
 651  * This function will reassemble a URL parsed with wfParseURL.  This is useful
 652  * if you need to edit part of a URL and put it back together.
 653  *
 654  * This is the basic structure used (brackets contain keys for $urlParts):
 655  * [scheme][delimiter][user]:[pass]@[host]:[port][path]?[query]#[fragment]
 656  *
 657  * @todo Need to integrate this into wfExpandUrl (bug 32168)
 658  *
 659  * @since 1.19
 660  * @param array $urlParts URL parts, as output from wfParseUrl
 661  * @return string URL assembled from its component parts
 662  */
 663 function wfAssembleUrl( $urlParts ) {
 664         $result = '';
 665
 666         if ( isset( $urlParts['delimiter'] ) ) {
 667                 if ( isset( $urlParts['scheme'] ) ) {
 668                         $result .= $urlParts['scheme'];
 669                 }
 670
 671                 $result .= $urlParts['delimiter'];
 672         }
 673
 674         if ( isset( $urlParts['host'] ) ) {
 675                 if ( isset( $urlParts['user'] ) ) {
 676                         $result .= $urlParts['user'];
 677                         if ( isset( $urlParts['pass'] ) ) {
 678                                 $result .= ':' . $urlParts['pass'];
 679                         }
 680                         $result .= '@';
 681                 }
 682
 683                 $result .= $urlParts['host'];
 684
 685                 if ( isset( $urlParts['port'] ) ) {
 686                         $result .= ':' . $urlParts['port'];
 687                 }
 688         }
 689
 690         if ( isset( $urlParts['path'] ) ) {
 691                 $result .= $urlParts['path'];
 692         }
 693
 694         if ( isset( $urlParts['query'] ) ) {
 695                 $result .= '?' . $urlParts['query'];
 696         }
 697
 698         if ( isset( $urlParts['fragment'] ) ) {
 699                 $result .= '#' . $urlParts['fragment'];
 700         }
 701
 702         return $result;
 703 }
 704
 705 /**
 706  * Remove all dot-segments in the provided URL path.  For example,
 707  * '/a/./b/../c/' becomes '/a/c/'.  For details on the algorithm, please see
 708  * RFC3986 section 5.2.4.
 709  *
 710  * @todo Need to integrate this into wfExpandUrl (bug 32168)
 711  *
 712  * @param string $urlPath URL path, potentially containing dot-segments
 713  * @return string URL path with all dot-segments removed
 714  */
 715 function wfRemoveDotSegments( $urlPath ) {
 716         $output = '';
 717         $inputOffset = 0;
 718         $inputLength = strlen( $urlPath );
 719
 720         while ( $inputOffset < $inputLength ) {
 721                 $prefixLengthOne = substr( $urlPath, $inputOffset, 1 );
 722                 $prefixLengthTwo = substr( $urlPath, $inputOffset, 2 );
 723                 $prefixLengthThree = substr( $urlPath, $inputOffset, 3 );
 724                 $prefixLengthFour = substr( $urlPath, $inputOffset, 4 );
 725                 $trimOutput = false;
 726
 727                 if ( $prefixLengthTwo == './' ) {
 728                         # Step A, remove leading "./"
 729                         $inputOffset += 2;
 730                 } elseif ( $prefixLengthThree == '../' ) {
 731                         # Step A, remove leading "../"
 732                         $inputOffset += 3;
 733                 } elseif ( ( $prefixLengthTwo == '/.' ) && ( $inputOffset + 2 == $inputLength ) ) {
 734                         # Step B, replace leading "/.$" with "/"
 735                         $inputOffset += 1;
 736                         $urlPath[$inputOffset] = '/';
 737                 } elseif ( $prefixLengthThree == '/./' ) {
 738                         # Step B, replace leading "/./" with "/"
 739                         $inputOffset += 2;
 740                 } elseif ( $prefixLengthThree == '/..' && ( $inputOffset + 3 == $inputLength ) ) {
 741                         # Step C, replace leading "/..$" with "/" and
 742                         # remove last path component in output
 743                         $inputOffset += 2;
 744                         $urlPath[$inputOffset] = '/';
 745                         $trimOutput = true;
 746                 } elseif ( $prefixLengthFour == '/../' ) {
 747                         # Step C, replace leading "/../" with "/" and
 748                         # remove last path component in output
 749                         $inputOffset += 3;
 750                         $trimOutput = true;
 751                 } elseif ( ( $prefixLengthOne == '.' ) && ( $inputOffset + 1 == $inputLength ) ) {
 752                         # Step D, remove "^.$"
 753                         $inputOffset += 1;
 754                 } elseif ( ( $prefixLengthTwo == '..' ) && ( $inputOffset + 2 == $inputLength ) ) {
 755                         # Step D, remove "^..$"
 756                         $inputOffset += 2;
 757                 } else {
 758                         # Step E, move leading path segment to output
 759                         if ( $prefixLengthOne == '/' ) {
 760                                 $slashPos = strpos( $urlPath, '/', $inputOffset + 1 );
 761                         } else {
 762                                 $slashPos = strpos( $urlPath, '/', $inputOffset );
 763                         }
 764                         if ( $slashPos === false ) {
 765                                 $output .= substr( $urlPath, $inputOffset );
 766                                 $inputOffset = $inputLength;
 767                         } else {
 768                                 $output .= substr( $urlPath, $inputOffset, $slashPos - $inputOffset );
 769                                 $inputOffset += $slashPos - $inputOffset;
 770                         }
 771                 }
 772
 773                 if ( $trimOutput ) {
 774                         $slashPos = strrpos( $output, '/' );
 775                         if ( $slashPos === false ) {
 776                                 $output = '';
 777                         } else {
 778                                 $output = substr( $output, 0, $slashPos );
 779                         }
 780                 }
 781         }
 782
 783         return $output;
 784 }
 785
 786 /**
 787  * Returns a regular expression of url protocols
 788  *
 789  * @param bool $includeProtocolRelative If false, remove '//' from the returned protocol list.
 790  *        DO NOT USE this directly, use wfUrlProtocolsWithoutProtRel() instead
 791  * @return string
 792  */
 793 function wfUrlProtocols( $includeProtocolRelative = true ) {
 794         global $wgUrlProtocols;
 795
 796         // Cache return values separately based on $includeProtocolRelative
 797         static $withProtRel = null, $withoutProtRel = null;
 798         $cachedValue = $includeProtocolRelative ? $withProtRel : $withoutProtRel;
 799         if ( !is_null( $cachedValue ) ) {
 800                 return $cachedValue;
 801         }
 802
 803         // Support old-style $wgUrlProtocols strings, for backwards compatibility
 804         // with LocalSettings files from 1.5
 805         if ( is_array( $wgUrlProtocols ) ) {
 806                 $protocols = array();
 807                 foreach ( $wgUrlProtocols as $protocol ) {
 808                         // Filter out '//' if !$includeProtocolRelative
 809                         if ( $includeProtocolRelative || $protocol !== '//' ) {
 810                                 $protocols[] = preg_quote( $protocol, '/' );
 811                         }
 812                 }
 813
 814                 $retval = implode( '|', $protocols );
 815         } else {
 816                 // Ignore $includeProtocolRelative in this case
 817                 // This case exists for pre-1.6 compatibility, and we can safely assume
 818                 // that '//' won't appear in a pre-1.6 config because protocol-relative
 819                 // URLs weren't supported until 1.18
 820                 $retval = $wgUrlProtocols;
 821         }
 822
 823         // Cache return value
 824         if ( $includeProtocolRelative ) {
 825                 $withProtRel = $retval;
 826         } else {
 827                 $withoutProtRel = $retval;
 828         }
 829         return $retval;
 830 }
 831
 832 /**
 833  * Like wfUrlProtocols(), but excludes '//' from the protocol list. Use this if
 834  * you need a regex that matches all URL protocols but does not match protocol-
 835  * relative URLs
 836  * @return string
 837  */
 838 function wfUrlProtocolsWithoutProtRel() {
 839         return wfUrlProtocols( false );
 840 }
 841
 842 /**
 843  * parse_url() work-alike, but non-broken.  Differences:
 844  *
 845  * 1) Does not raise warnings on bad URLs (just returns false).
 846  * 2) Handles protocols that don't use :// (e.g., mailto: and news:, as well as
 847  *    protocol-relative URLs) correctly.
 848  * 3) Adds a "delimiter" element to the array, either '://', ':' or '//' (see (2)).
 849  *
 850  * @param string $url A URL to parse
 851  * @return string[] Bits of the URL in an associative array, per PHP docs
 852  */
 853 function wfParseUrl( $url ) {
 854         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
 855
 856         // Protocol-relative URLs are handled really badly by parse_url(). It's so
 857         // bad that the easiest way to handle them is to just prepend 'http:' and
 858         // strip the protocol out later.
 859         $wasRelative = substr( $url, 0, 2 ) == '//';
 860         if ( $wasRelative ) {
 861                 $url = "http:$url";
 862         }
 863         MediaWiki\suppressWarnings();
 864         $bits = parse_url( $url );
 865         MediaWiki\restoreWarnings();
 866         // parse_url() returns an array without scheme for some invalid URLs, e.g.
 867         // parse_url("%0Ahttp://example.com") == array( 'host' => '%0Ahttp', 'path' => 'example.com' )
 868         if ( !$bits || !isset( $bits['scheme'] ) ) {
 869                 return false;
 870         }
 871
 872         // parse_url() incorrectly handles schemes case-sensitively. Convert it to lowercase.
 873         $bits['scheme'] = strtolower( $bits['scheme'] );
 874
 875         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
 876         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
 877                 $bits['delimiter'] = '://';
 878         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
 879                 $bits['delimiter'] = ':';
 880                 // parse_url detects for news: and mailto: the host part of an url as path
 881                 // We have to correct this wrong detection
 882                 if ( isset( $bits['path'] ) ) {
 883                         $bits['host'] = $bits['path'];
 884                         $bits['path'] = '';
 885                 }
 886         } else {
 887                 return false;
 888         }
 889
 890         /* Provide an empty host for eg. file:/// urls (see bug 28627) */
 891         if ( !isset( $bits['host'] ) ) {
 892                 $bits['host'] = '';
 893
 894                 // bug 45069
 895                 if ( isset( $bits['path'] ) ) {
 896                         /* parse_url loses the third / for file:///c:/ urls (but not on variants) */
 897                         if ( substr( $bits['path'], 0, 1 ) !== '/' ) {
 898                                 $bits['path'] = '/' . $bits['path'];
 899                         }
 900                 } else {
 901                         $bits['path'] = '';
 902                 }
 903         }
 904
 905         // If the URL was protocol-relative, fix scheme and delimiter
 906         if ( $wasRelative ) {
 907                 $bits['scheme'] = '';
 908                 $bits['delimiter'] = '//';
 909         }
 910         return $bits;
 911 }
 912
 913 /**
 914  * Take a URL, make sure it's expanded to fully qualified, and replace any
 915  * encoded non-ASCII Unicode characters with their UTF-8 original forms
 916  * for more compact display and legibility for local audiences.
 917  *
 918  * @todo handle punycode domains too
 919  *
 920  * @param string $url
 921  * @return string
 922  */
 923 function wfExpandIRI( $url ) {
 924         return preg_replace_callback(
 925                 '/((?:%[89A-F][0-9A-F])+)/i',
 926                 'wfExpandIRI_callback',
 927                 wfExpandUrl( $url )
 928         );
 929 }
 930
 931 /**
 932  * Private callback for wfExpandIRI
 933  * @param array $matches
 934  * @return string
 935  */
 936 function wfExpandIRI_callback( $matches ) {
 937         return urldecode( $matches[1] );
 938 }
 939
 940 /**
 941  * Make URL indexes, appropriate for the el_index field of externallinks.
 942  *
 943  * @param string $url
 944  * @return array
 945  */
 946 function wfMakeUrlIndexes( $url ) {
 947         $bits = wfParseUrl( $url );
 948
 949         // Reverse the labels in the hostname, convert to lower case
 950         // For emails reverse domainpart only
 951         if ( $bits['scheme'] == 'mailto' ) {
 952                 $mailparts = explode( '@', $bits['host'], 2 );
 953                 if ( count( $mailparts ) === 2 ) {
 954                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
 955                 } else {
 956                         // No domain specified, don't mangle it
 957                         $domainpart = '';
 958                 }
 959                 $reversedHost = $domainpart . '@' . $mailparts[0];
 960         } else {
 961                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
 962         }
 963         // Add an extra dot to the end
 964         // Why? Is it in wrong place in mailto links?
 965         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
 966                 $reversedHost .= '.';
 967         }
 968         // Reconstruct the pseudo-URL
 969         $prot = $bits['scheme'];
 970         $index = $prot . $bits['delimiter'] . $reversedHost;
 971         // Leave out user and password. Add the port, path, query and fragment
 972         if ( isset( $bits['port'] ) ) {
 973                 $index .= ':' . $bits['port'];
 974         }
 975         if ( isset( $bits['path'] ) ) {
 976                 $index .= $bits['path'];
 977         } else {
 978                 $index .= '/';
 979         }
 980         if ( isset( $bits['query'] ) ) {
 981                 $index .= '?' . $bits['query'];
 982         }
 983         if ( isset( $bits['fragment'] ) ) {
 984                 $index .= '#' . $bits['fragment'];
 985         }
 986
 987         if ( $prot == '' ) {
 988                 return array( "http:$index", "https:$index" );
 989         } else {
 990                 return array( $index );
 991         }
 992 }
 993
 994 /**
 995  * Check whether a given URL has a domain that occurs in a given set of domains
 996  * @param string $url URL
 997  * @param array $domains Array of domains (strings)
 998  * @return bool True if the host part of $url ends in one of the strings in $domains
 999  */
1000 function wfMatchesDomainList( $url, $domains ) {
1001         $bits = wfParseUrl( $url );
1002         if ( is_array( $bits ) && isset( $bits['host'] ) ) {
1003                 $host = '.' . $bits['host'];
1004                 foreach ( (array)$domains as $domain ) {
1005                         $domain = '.' . $domain;
1006                         if ( substr( $host, -strlen( $domain ) ) === $domain ) {
1007                                 return true;
1008                         }
1009                 }
1010         }
1011         return false;
1012 }
1013
1014 /**
1015  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
1016  * In normal operation this is a NOP.
1017  *
1018  * Controlling globals:
1019  * $wgDebugLogFile - points to the log file
1020  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
1021  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
1022  *
1023  * @since 1.25 support for additional context data
1024  *
1025  * @param string $text
1026  * @param string|bool $dest Unused
1027  * @param array $context Additional logging context data
1028  */
1029 function wfDebug( $text, $dest = 'all', array $context = array() ) {
1030         global $wgDebugRawPage, $wgDebugLogPrefix;
1031         global $wgDebugTimestamps, $wgRequestTime;
1032
1033         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
1034                 return;
1035         }
1036
1037         $text = trim( $text );
1038
1039         // Inline logic from deprecated wfDebugTimer()
1040         if ( $wgDebugTimestamps ) {
1041                 $context['seconds_elapsed'] = sprintf(
1042                         '%6.4f',
1043                         microtime( true ) - $wgRequestTime
1044                 );
1045                 $context['memory_used'] = sprintf(
1046                         '%5.1fM',
1047                         ( memory_get_usage( true ) / ( 1024 * 1024 ) )
1048                 );
1049         }
1050
1051         if ( $wgDebugLogPrefix !== '' ) {
1052                 $context['prefix'] = $wgDebugLogPrefix;
1053         }
1054
1055         $logger = LoggerFactory::getInstance( 'wfDebug' );
1056         $logger->debug( $text, $context );
1057 }
1058
1059 /**
1060  * Returns true if debug logging should be suppressed if $wgDebugRawPage = false
1061  * @return bool
1062  */
1063 function wfIsDebugRawPage() {
1064         static $cache;
1065         if ( $cache !== null ) {
1066                 return $cache;
1067         }
1068         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
1069         if ( ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' )
1070                 || (
1071                         isset( $_SERVER['SCRIPT_NAME'] )
1072                         && substr( $_SERVER['SCRIPT_NAME'], -8 ) == 'load.php'
1073                 )
1074         ) {
1075                 $cache = true;
1076         } else {
1077                 $cache = false;
1078         }
1079         return $cache;
1080 }
1081
1082 /**
1083  * Get microsecond timestamps for debug logs
1084  *
1085  * @deprecated since 1.25
1086  * @return string
1087  */
1088 function wfDebugTimer() {
1089         global $wgDebugTimestamps, $wgRequestTime;
1090
1091         wfDeprecated( __METHOD__, '1.25' );
1092
1093         if ( !$wgDebugTimestamps ) {
1094                 return '';
1095         }
1096
1097         $prefix = sprintf( "%6.4f", microtime( true ) - $wgRequestTime );
1098         $mem = sprintf( "%5.1fM", ( memory_get_usage( true ) / ( 1024 * 1024 ) ) );
1099         return "$prefix $mem  ";
1100 }
1101
1102 /**
1103  * Send a line giving PHP memory usage.
1104  *
1105  * @param bool $exact Print exact byte values instead of kibibytes (default: false)
1106  */
1107 function wfDebugMem( $exact = false ) {
1108         $mem = memory_get_usage();
1109         if ( !$exact ) {
1110                 $mem = floor( $mem / 1024 ) . ' KiB';
1111         } else {
1112                 $mem .= ' B';
1113         }
1114         wfDebug( "Memory usage: $mem\n" );
1115 }
1116
1117 /**
1118  * Send a line to a supplementary debug log file, if configured, or main debug
1119  * log if not.
1120  *
1121  * To configure a supplementary log file, set $wgDebugLogGroups[$logGroup] to
1122  * a string filename or an associative array mapping 'destination' to the
1123  * desired filename. The associative array may also contain a 'sample' key
1124  * with an integer value, specifying a sampling factor. Sampled log events
1125  * will be emitted with a 1 in N random chance.
1126  *
1127  * @since 1.23 support for sampling log messages via $wgDebugLogGroups.
1128  * @since 1.25 support for additional context data
1129  * @since 1.25 sample behavior dependent on configured $wgMWLoggerDefaultSpi
1130  *
1131  * @param string $logGroup
1132  * @param string $text
1133  * @param string|bool $dest Destination of the message:
1134  *     - 'all': both to the log and HTML (debug toolbar or HTML comments)
1135  *     - 'log': only to the log and not in HTML
1136  *     - 'private': only to the specific log if set in $wgDebugLogGroups and
1137  *       discarded otherwise
1138  *   For backward compatibility, it can also take a boolean:
1139  *     - true: same as 'all'
1140  *     - false: same as 'private'
1141  * @param array $context Additional logging context data
1142  */
1143 function wfDebugLog(
1144         $logGroup, $text, $dest = 'all', array $context = array()
1145 ) {
1146         // Turn $dest into a string if it's a boolean (for b/c)
1147         if ( $dest === true ) {
1148                 $dest = 'all';
1149         } elseif ( $dest === false ) {
1150                 $dest = 'private';
1151         }
1152
1153         $text = trim( $text );
1154
1155         $logger = LoggerFactory::getInstance( $logGroup );
1156         $context['private'] = ( $dest === 'private' );
1157         $logger->info( $text, $context );
1158 }
1159
1160 /**
1161  * Log for database errors
1162  *
1163  * @since 1.25 support for additional context data
1164  *
1165  * @param string $text Database error message.
1166  * @param array $context Additional logging context data
1167  */
1168 function wfLogDBError( $text, array $context = array() ) {
1169         $logger = LoggerFactory::getInstance( 'wfLogDBError' );
1170         $logger->error( trim( $text ), $context );
1171 }
1172
1173 /**
1174  * Throws a warning that $function is deprecated
1175  *
1176  * @param string $function
1177  * @param string|bool $version Version of MediaWiki that the function
1178  *    was deprecated in (Added in 1.19).
1179  * @param string|bool $component Added in 1.19.
1180  * @param int $callerOffset How far up the call stack is the original
1181  *    caller. 2 = function that called the function that called
1182  *    wfDeprecated (Added in 1.20)
1183  *
1184  * @return null
1185  */
1186 function wfDeprecated( $function, $version = false, $component = false, $callerOffset = 2 ) {
1187         MWDebug::deprecated( $function, $version, $component, $callerOffset + 1 );
1188 }
1189
1190 /**
1191  * Send a warning either to the debug log or in a PHP error depending on
1192  * $wgDevelopmentWarnings. To log warnings in production, use wfLogWarning() instead.
1193  *
1194  * @param string $msg Message to send
1195  * @param int $callerOffset Number of items to go back in the backtrace to
1196  *        find the correct caller (1 = function calling wfWarn, ...)
1197  * @param int $level PHP error level; defaults to E_USER_NOTICE;
1198  *        only used when $wgDevelopmentWarnings is true
1199  */
1200 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
1201         MWDebug::warning( $msg, $callerOffset + 1, $level, 'auto' );
1202 }
1203
1204 /**
1205  * Send a warning as a PHP error and the debug log. This is intended for logging
1206  * warnings in production. For logging development warnings, use WfWarn instead.
1207  *
1208  * @param string $msg Message to send
1209  * @param int $callerOffset Number of items to go back in the backtrace to
1210  *        find the correct caller (1 = function calling wfLogWarning, ...)
1211  * @param int $level PHP error level; defaults to E_USER_WARNING
1212  */
1213 function wfLogWarning( $msg, $callerOffset = 1, $level = E_USER_WARNING ) {
1214         MWDebug::warning( $msg, $callerOffset + 1, $level, 'production' );
1215 }
1216
1217 /**
1218  * Log to a file without getting "file size exceeded" signals.
1219  *
1220  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
1221  * send lines to the specified port, prefixed by the specified prefix and a space.
1222  * @since 1.25 support for additional context data
1223  *
1224  * @param string $text
1225  * @param string $file Filename
1226  * @param array $context Additional logging context data
1227  * @throws MWException
1228  * @deprecated since 1.25 Use MediaWiki\Logger\LegacyLogger::emit or UDPTransport
1229  */
1230 function wfErrorLog( $text, $file, array $context = array() ) {
1231         wfDeprecated( __METHOD__, '1.25' );
1232         $logger = LoggerFactory::getInstance( 'wfErrorLog' );
1233         $context['destination'] = $file;
1234         $logger->info( trim( $text ), $context );
1235 }
1236
1237 /**
1238  * @todo document
1239  */
1240 function wfLogProfilingData() {
1241         global $wgDebugLogGroups, $wgDebugRawPage;
1242
1243         $context = RequestContext::getMain();
1244         $request = $context->getRequest();
1245
1246         $profiler = Profiler::instance();
1247         $profiler->setContext( $context );
1248         $profiler->logData();
1249
1250         $config = $context->getConfig();
1251         if ( $config->has( 'StatsdServer' ) ) {
1252                 $statsdServer = explode( ':', $config->get( 'StatsdServer' ) );
1253                 $statsdHost = $statsdServer[0];
1254                 $statsdPort = isset( $statsdServer[1] ) ? $statsdServer[1] : 8125;
1255                 $statsdSender = new SocketSender( $statsdHost, $statsdPort );
1256                 $statsdClient = new StatsdClient( $statsdSender );
1257                 $statsdClient->send( $context->getStats()->getBuffer() );
1258         }
1259
1260         # Profiling must actually be enabled...
1261         if ( $profiler instanceof ProfilerStub ) {
1262                 return;
1263         }
1264
1265         if ( isset( $wgDebugLogGroups['profileoutput'] )
1266                 && $wgDebugLogGroups['profileoutput'] === false
1267         ) {
1268                 // Explicitly disabled
1269                 return;
1270         }
1271         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
1272                 return;
1273         }
1274
1275         $ctx = array( 'elapsed' => $request->getElapsedTime() );
1276         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
1277                 $ctx['forwarded_for'] = $_SERVER['HTTP_X_FORWARDED_FOR'];
1278         }
1279         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
1280                 $ctx['client_ip'] = $_SERVER['HTTP_CLIENT_IP'];
1281         }
1282         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
1283                 $ctx['from'] = $_SERVER['HTTP_FROM'];
1284         }
1285         if ( isset( $ctx['forwarded_for'] ) ||
1286                 isset( $ctx['client_ip'] ) ||
1287                 isset( $ctx['from'] ) ) {
1288                 $ctx['proxy'] = $_SERVER['REMOTE_ADDR'];
1289         }
1290
1291         // Don't load $wgUser at this late stage just for statistics purposes
1292         // @todo FIXME: We can detect some anons even if it is not loaded.
1293         // See User::getId()
1294         $user = $context->getUser();
1295         $ctx['anon'] = $user->isItemLoaded( 'id' ) && $user->isAnon();
1296
1297         // Command line script uses a FauxRequest object which does not have
1298         // any knowledge about an URL and throw an exception instead.
1299         try {
1300                 $ctx['url'] = urldecode( $request->getRequestURL() );
1301         } catch ( Exception $ignored ) {
1302                 // no-op
1303         }
1304
1305         $ctx['output'] = $profiler->getOutput();
1306
1307         $log = LoggerFactory::getInstance( 'profileoutput' );
1308         $log->info( "Elapsed: {elapsed}; URL: <{url}>\n{output}", $ctx );
1309 }
1310
1311 /**
1312  * Increment a statistics counter
1313  *
1314  * @param string $key
1315  * @param int $count
1316  * @return void
1317  */
1318 function wfIncrStats( $key, $count = 1 ) {
1319         $stats = RequestContext::getMain()->getStats();
1320         $stats->updateCount( $key, $count );
1321 }
1322
1323 /**
1324  * Check whether the wiki is in read-only mode.
1325  *
1326  * @return bool
1327  */
1328 function wfReadOnly() {
1329         return wfReadOnlyReason() !== false;
1330 }
1331
1332 /**
1333  * Get the value of $wgReadOnly or the contents of $wgReadOnlyFile.
1334  *
1335  * @return string|bool String when in read-only mode; false otherwise
1336  */
1337 function wfReadOnlyReason() {
1338         global $wgReadOnly, $wgReadOnlyFile;
1339
1340         if ( $wgReadOnly === null ) {
1341                 // Set $wgReadOnly for faster access next time
1342                 if ( is_file( $wgReadOnlyFile ) && filesize( $wgReadOnlyFile ) > 0 ) {
1343                         $wgReadOnly = file_get_contents( $wgReadOnlyFile );
1344                 } else {
1345                         $wgReadOnly = false;
1346                 }
1347                 // Callers use this method to be aware that data presented to a user
1348                 // may be very stale and thus allowing submissions can be problematic.
1349                 try {
1350                         if ( $wgReadOnly === false && wfGetLB()->getLaggedSlaveMode() ) {
1351                                 $wgReadOnly = 'The database has been automatically locked ' .
1352                                         'while the slave database servers catch up to the master';
1353                         }
1354                 } catch ( DBConnectionError $e ) {
1355                         $wgReadOnly = 'The database has been automatically locked ' .
1356                                 'until the slave database servers become available';
1357                 }
1358         }
1359
1360         return $wgReadOnly;
1361 }
1362
1363 /**
1364  * Return a Language object from $langcode
1365  *
1366  * @param Language|string|bool $langcode Either:
1367  *                  - a Language object
1368  *                  - code of the language to get the message for, if it is
1369  *                    a valid code create a language for that language, if
1370  *                    it is a string but not a valid code then make a basic
1371  *                    language object
1372  *                  - a boolean: if it's false then use the global object for
1373  *                    the current user's language (as a fallback for the old parameter
1374  *                    functionality), or if it is true then use global object
1375  *                    for the wiki's content language.
1376  * @return Language
1377  */
1378 function wfGetLangObj( $langcode = false ) {
1379         # Identify which language to get or create a language object for.
1380         # Using is_object here due to Stub objects.
1381         if ( is_object( $langcode ) ) {
1382                 # Great, we already have the object (hopefully)!
1383                 return $langcode;
1384         }
1385
1386         global $wgContLang, $wgLanguageCode;
1387         if ( $langcode === true || $langcode === $wgLanguageCode ) {
1388                 # $langcode is the language code of the wikis content language object.
1389                 # or it is a boolean and value is true
1390                 return $wgContLang;
1391         }
1392
1393         global $wgLang;
1394         if ( $langcode === false || $langcode === $wgLang->getCode() ) {
1395                 # $langcode is the language code of user language object.
1396                 # or it was a boolean and value is false
1397                 return $wgLang;
1398         }
1399
1400         $validCodes = array_keys( Language::fetchLanguageNames() );
1401         if ( in_array( $langcode, $validCodes ) ) {
1402                 # $langcode corresponds to a valid language.
1403                 return Language::factory( $langcode );
1404         }
1405
1406         # $langcode is a string, but not a valid language code; use content language.
1407         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
1408         return $wgContLang;
1409 }
1410
1411 /**
1412  * This is the function for getting translated interface messages.
1413  *
1414  * @see Message class for documentation how to use them.
1415  * @see https://www.mediawiki.org/wiki/Manual:Messages_API
1416  *
1417  * This function replaces all old wfMsg* functions.
1418  *
1419  * @param string|string[] $key Message key, or array of keys
1420  * @param mixed $params,... Normal message parameters
1421  * @return Message
1422  *
1423  * @since 1.17
1424  *
1425  * @see Message::__construct
1426  */
1427 function wfMessage( $key /*...*/ ) {
1428         $params = func_get_args();
1429         array_shift( $params );
1430         if ( isset( $params[0] ) && is_array( $params[0] ) ) {
1431                 $params = $params[0];
1432         }
1433         return new Message( $key, $params );
1434 }
1435
1436 /**
1437  * This function accepts multiple message keys and returns a message instance
1438  * for the first message which is non-empty. If all messages are empty then an
1439  * instance of the first message key is returned.
1440  *
1441  * @param string|string[] $keys,... Message keys
1442  * @return Message
1443  *
1444  * @since 1.18
1445  *
1446  * @see Message::newFallbackSequence
1447  */
1448 function wfMessageFallback( /*...*/ ) {
1449         $args = func_get_args();
1450         return call_user_func_array( 'Message::newFallbackSequence', $args );
1451 }
1452
1453 /**
1454  * Get a message from anywhere, for the current user language.
1455  *
1456  * Use wfMsgForContent() instead if the message should NOT
1457  * change depending on the user preferences.
1458  *
1459  * @deprecated since 1.18
1460  *
1461  * @param string $key Lookup key for the message, usually
1462  *    defined in languages/Language.php
1463  *
1464  * Parameters to the message, which can be used to insert variable text into
1465  * it, can be passed to this function in the following formats:
1466  * - One per argument, starting at the second parameter
1467  * - As an array in the second parameter
1468  * These are not shown in the function definition.
1469  *
1470  * @return string
1471  */
1472 function wfMsg( $key ) {
1473         wfDeprecated( __METHOD__, '1.21' );
1474
1475         $args = func_get_args();
1476         array_shift( $args );
1477         return wfMsgReal( $key, $args );
1478 }
1479
1480 /**
1481  * Same as above except doesn't transform the message
1482  *
1483  * @deprecated since 1.18
1484  *
1485  * @param string $key
1486  * @return string
1487  */
1488 function wfMsgNoTrans( $key ) {
1489         wfDeprecated( __METHOD__, '1.21' );
1490
1491         $args = func_get_args();
1492         array_shift( $args );
1493         return wfMsgReal( $key, $args, true, false, false );
1494 }
1495
1496 /**
1497  * Get a message from anywhere, for the current global language
1498  * set with $wgLanguageCode.
1499  *
1500  * Use this if the message should NOT change dependent on the
1501  * language set in the user's preferences. This is the case for
1502  * most text written into logs, as well as link targets (such as
1503  * the name of the copyright policy page). Link titles, on the
1504  * other hand, should be shown in the UI language.
1505  *
1506  * Note that MediaWiki allows users to change the user interface
1507  * language in their preferences, but a single installation
1508  * typically only contains content in one language.
1509  *
1510  * Be wary of this distinction: If you use wfMsg() where you should
1511  * use wfMsgForContent(), a user of the software may have to
1512  * customize potentially hundreds of messages in
1513  * order to, e.g., fix a link in every possible language.
1514  *
1515  * @deprecated since 1.18
1516  *
1517  * @param string $key Lookup key for the message, usually
1518  *     defined in languages/Language.php
1519  * @return string
1520  */
1521 function wfMsgForContent( $key ) {
1522         wfDeprecated( __METHOD__, '1.21' );
1523
1524         global $wgForceUIMsgAsContentMsg;
1525         $args = func_get_args();
1526         array_shift( $args );
1527         $forcontent = true;
1528         if ( is_array( $wgForceUIMsgAsContentMsg )
1529                 && in_array( $key, $wgForceUIMsgAsContentMsg )
1530         ) {
1531                 $forcontent = false;
1532         }
1533         return wfMsgReal( $key, $args, true, $forcontent );
1534 }
1535
1536 /**
1537  * Same as above except doesn't transform the message
1538  *
1539  * @deprecated since 1.18
1540  *
1541  * @param string $key
1542  * @return string
1543  */
1544 function wfMsgForContentNoTrans( $key ) {
1545         wfDeprecated( __METHOD__, '1.21' );
1546
1547         global $wgForceUIMsgAsContentMsg;
1548         $args = func_get_args();
1549         array_shift( $args );
1550         $forcontent = true;
1551         if ( is_array( $wgForceUIMsgAsContentMsg )
1552                 && in_array( $key, $wgForceUIMsgAsContentMsg )
1553         ) {
1554                 $forcontent = false;
1555         }
1556         return wfMsgReal( $key, $args, true, $forcontent, false );
1557 }
1558
1559 /**
1560  * Really get a message
1561  *
1562  * @deprecated since 1.18
1563  *
1564  * @param string $key Key to get.
1565  * @param array $args
1566  * @param bool $useDB
1567  * @param string|bool $forContent Language code, or false for user lang, true for content lang.
1568  * @param bool $transform Whether or not to transform the message.
1569  * @return string The requested message.
1570  */
1571 function wfMsgReal( $key, $args, $useDB = true, $forContent = false, $transform = true ) {
1572         wfDeprecated( __METHOD__, '1.21' );
1573
1574         $message = wfMsgGetKey( $key, $useDB, $forContent, $transform );
1575         $message = wfMsgReplaceArgs( $message, $args );
1576         return $message;
1577 }
1578
1579 /**
1580  * Fetch a message string value, but don't replace any keys yet.
1581  *
1582  * @deprecated since 1.18
1583  *
1584  * @param string $key
1585  * @param bool $useDB
1586  * @param string|bool $langCode Code of the language to get the message for, or
1587  *   behaves as a content language switch if it is a boolean.
1588  * @param bool $transform Whether to parse magic words, etc.
1589  * @return string
1590  */
1591 function wfMsgGetKey( $key, $useDB = true, $langCode = false, $transform = true ) {
1592         wfDeprecated( __METHOD__, '1.21' );
1593
1594         Hooks::run( 'NormalizeMessageKey', array( &$key, &$useDB, &$langCode, &$transform ) );
1595
1596         $cache = MessageCache::singleton();
1597         $message = $cache->get( $key, $useDB, $langCode );
1598         if ( $message === false ) {
1599                 $message = '&lt;' . htmlspecialchars( $key ) . '&gt;';
1600         } elseif ( $transform ) {
1601                 $message = $cache->transform( $message );
1602         }
1603         return $message;
1604 }
1605
1606 /**
1607  * Replace message parameter keys on the given formatted output.
1608  *
1609  * @param string $message
1610  * @param array $args
1611  * @return string
1612  * @private
1613  */
1614 function wfMsgReplaceArgs( $message, $args ) {
1615         # Fix windows line-endings
1616         # Some messages are split with explode("\n", $msg)
1617         $message = str_replace( "\r", '', $message );
1618
1619         // Replace arguments
1620         if ( count( $args ) ) {
1621                 if ( is_array( $args[0] ) ) {
1622                         $args = array_values( $args[0] );
1623                 }
1624                 $replacementKeys = array();
1625                 foreach ( $args as $n => $param ) {
1626                         $replacementKeys['$' . ( $n + 1 )] = $param;
1627                 }
1628                 $message = strtr( $message, $replacementKeys );
1629         }
1630
1631         return $message;
1632 }
1633
1634 /**
1635  * Return an HTML-escaped version of a message.
1636  * Parameter replacements, if any, are done *after* the HTML-escaping,
1637  * so parameters may contain HTML (eg links or form controls). Be sure
1638  * to pre-escape them if you really do want plaintext, or just wrap
1639  * the whole thing in htmlspecialchars().
1640  *
1641  * @deprecated since 1.18
1642  *
1643  * @param string $key
1644  * @param string $args,... Parameters
1645  * @return string
1646  */
1647 function wfMsgHtml( $key ) {
1648         wfDeprecated( __METHOD__, '1.21' );
1649
1650         $args = func_get_args();
1651         array_shift( $args );
1652         return wfMsgReplaceArgs( htmlspecialchars( wfMsgGetKey( $key ) ), $args );
1653 }
1654
1655 /**
1656  * Return an HTML version of message
1657  * Parameter replacements, if any, are done *after* parsing the wiki-text message,
1658  * so parameters may contain HTML (eg links or form controls). Be sure
1659  * to pre-escape them if you really do want plaintext, or just wrap
1660  * the whole thing in htmlspecialchars().
1661  *
1662  * @deprecated since 1.18
1663  *
1664  * @param string $key
1665  * @param string $args,... Parameters
1666  * @return string
1667  */
1668 function wfMsgWikiHtml( $key ) {
1669         wfDeprecated( __METHOD__, '1.21' );
1670
1671         $args = func_get_args();
1672         array_shift( $args );
1673         return wfMsgReplaceArgs(
1674                 MessageCache::singleton()->parse( wfMsgGetKey( $key ), null,
1675                 /* can't be set to false */ true, /* interface */ true )->getText(),
1676                 $args );
1677 }
1678
1679 /**
1680  * Returns message in the requested format
1681  *
1682  * @deprecated since 1.18
1683  *
1684  * @param string $key Key of the message
1685  * @param array $options Processing rules.
1686  *   Can take the following options:
1687  *     parse: parses wikitext to HTML
1688  *     parseinline: parses wikitext to HTML and removes the surrounding
1689  *       p's added by parser or tidy
1690  *     escape: filters message through htmlspecialchars
1691  *     escapenoentities: same, but allows entity references like &#160; through
1692  *     replaceafter: parameters are substituted after parsing or escaping
1693  *     parsemag: transform the message using magic phrases
1694  *     content: fetch message for content language instead of interface
1695  *   Also can accept a single associative argument, of the form 'language' => 'xx':
1696  *     language: Language object or language code to fetch message for
1697  *       (overridden by content).
1698  * Behavior for conflicting options (e.g., parse+parseinline) is undefined.
1699  *
1700  * @return string
1701  */
1702 function wfMsgExt( $key, $options ) {
1703         wfDeprecated( __METHOD__, '1.21' );
1704
1705         $args = func_get_args();
1706         array_shift( $args );
1707         array_shift( $args );
1708         $options = (array)$options;
1709         $validOptions = array( 'parse', 'parseinline', 'escape', 'escapenoentities', 'replaceafter',
1710                 'parsemag', 'content' );
1711
1712         foreach ( $options as $arrayKey => $option ) {
1713                 if ( !preg_match( '/^[0-9]+|language$/', $arrayKey ) ) {
1714                         // An unknown index, neither numeric nor "language"
1715                         wfWarn( "wfMsgExt called with incorrect parameter key $arrayKey", 1, E_USER_WARNING );
1716                 } elseif ( preg_match( '/^[0-9]+$/', $arrayKey ) && !in_array( $option, $validOptions ) ) {
1717                         // A numeric index with unknown value
1718                         wfWarn( "wfMsgExt called with incorrect parameter $option", 1, E_USER_WARNING );
1719                 }
1720         }
1721
1722         if ( in_array( 'content', $options, true ) ) {
1723                 $forContent = true;
1724                 $langCode = true;
1725                 $langCodeObj = null;
1726         } elseif ( array_key_exists( 'language', $options ) ) {
1727                 $forContent = false;
1728                 $langCode = wfGetLangObj( $options['language'] );
1729                 $langCodeObj = $langCode;
1730         } else {
1731                 $forContent = false;
1732                 $langCode = false;
1733                 $langCodeObj = null;
1734         }
1735
1736         $string = wfMsgGetKey( $key, /*DB*/true, $langCode, /*Transform*/false );
1737
1738         if ( !in_array( 'replaceafter', $options, true ) ) {
1739                 $string = wfMsgReplaceArgs( $string, $args );
1740         }
1741
1742         $messageCache = MessageCache::singleton();
1743         $parseInline = in_array( 'parseinline', $options, true );
1744         if ( in_array( 'parse', $options, true ) || $parseInline ) {
1745                 $string = $messageCache->parse( $string, null, true, !$forContent, $langCodeObj );
1746                 if ( $string instanceof ParserOutput ) {
1747                         $string = $string->getText();
1748                 }
1749
1750                 if ( $parseInline ) {
1751                         $string = Parser::stripOuterParagraph( $string );
1752                 }
1753         } elseif ( in_array( 'parsemag', $options, true ) ) {
1754                 $string = $messageCache->transform( $string,
1755                                 !$forContent, $langCodeObj );
1756         }
1757
1758         if ( in_array( 'escape', $options, true ) ) {
1759                 $string = htmlspecialchars ( $string );
1760         } elseif ( in_array( 'escapenoentities', $options, true ) ) {
1761                 $string = Sanitizer::escapeHtmlAllowEntities( $string );
1762         }
1763
1764         if ( in_array( 'replaceafter', $options, true ) ) {
1765                 $string = wfMsgReplaceArgs( $string, $args );
1766         }
1767
1768         return $string;
1769 }
1770
1771 /**
1772  * Since wfMsg() and co suck, they don't return false if the message key they
1773  * looked up didn't exist but instead the key wrapped in <>'s, this function checks for the
1774  * nonexistence of messages by checking the MessageCache::get() result directly.
1775  *
1776  * @deprecated since 1.18. Use Message::isDisabled().
1777  *
1778  * @param string $key The message key looked up
1779  * @return bool True if the message *doesn't* exist.
1780  */
1781 function wfEmptyMsg( $key ) {
1782         wfDeprecated( __METHOD__, '1.21' );
1783
1784         return MessageCache::singleton()->get( $key, /*useDB*/true, /*content*/false ) === false;
1785 }
1786
1787 /**
1788  * Fetch server name for use in error reporting etc.
1789  * Use real server name if available, so we know which machine
1790  * in a server farm generated the current page.
1791  *
1792  * @return string
1793  */
1794 function wfHostname() {
1795         static $host;
1796         if ( is_null( $host ) ) {
1797
1798                 # Hostname overriding
1799                 global $wgOverrideHostname;
1800                 if ( $wgOverrideHostname !== false ) {
1801                         # Set static and skip any detection
1802                         $host = $wgOverrideHostname;
1803                         return $host;
1804                 }
1805
1806                 if ( function_exists( 'posix_uname' ) ) {
1807                         // This function not present on Windows
1808                         $uname = posix_uname();
1809                 } else {
1810                         $uname = false;
1811                 }
1812                 if ( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1813                         $host = $uname['nodename'];
1814                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1815                         # Windows computer name
1816                         $host = getenv( 'COMPUTERNAME' );
1817                 } else {
1818                         # This may be a virtual server.
1819                         $host = $_SERVER['SERVER_NAME'];
1820                 }
1821         }
1822         return $host;
1823 }
1824
1825 /**
1826  * Returns a script tag that stores the amount of time it took MediaWiki to
1827  * handle the request in milliseconds as 'wgBackendResponseTime'.
1828  *
1829  * If $wgShowHostnames is true, the script will also set 'wgHostname' to the
1830  * hostname of the server handling the request.
1831  *
1832  * @return string
1833  */
1834 function wfReportTime() {
1835         global $wgRequestTime, $wgShowHostnames;
1836
1837         $responseTime = round( ( microtime( true ) - $wgRequestTime ) * 1000 );
1838         $reportVars = array( 'wgBackendResponseTime' => $responseTime );
1839         if ( $wgShowHostnames ) {
1840                 $reportVars['wgHostname'] = wfHostname();
1841         }
1842         return Skin::makeVariablesScript( $reportVars );
1843 }
1844
1845 /**
1846  * Safety wrapper for debug_backtrace().
1847  *
1848  * Will return an empty array if debug_backtrace is disabled, otherwise
1849  * the output from debug_backtrace() (trimmed).
1850  *
1851  * @param int $limit This parameter can be used to limit the number of stack frames returned
1852  *
1853  * @return array Array of backtrace information
1854  */
1855 function wfDebugBacktrace( $limit = 0 ) {
1856         static $disabled = null;
1857
1858         if ( is_null( $disabled ) ) {
1859                 $disabled = !function_exists( 'debug_backtrace' );
1860                 if ( $disabled ) {
1861                         wfDebug( "debug_backtrace() is disabled\n" );
1862                 }
1863         }
1864         if ( $disabled ) {
1865                 return array();
1866         }
1867
1868         if ( $limit && version_compare( PHP_VERSION, '5.4.0', '>=' ) ) {
1869                 return array_slice( debug_backtrace( DEBUG_BACKTRACE_PROVIDE_OBJECT, $limit + 1 ), 1 );
1870         } else {
1871                 return array_slice( debug_backtrace(), 1 );
1872         }
1873 }
1874
1875 /**
1876  * Get a debug backtrace as a string
1877  *
1878  * @param bool|null $raw If true, the return value is plain text. If false, HTML.
1879  *   Defaults to $wgCommandLineMode if unset.
1880  * @return string
1881  * @since 1.25 Supports $raw parameter.
1882  */
1883 function wfBacktrace( $raw = null ) {
1884         global $wgCommandLineMode;
1885
1886         if ( $raw === null ) {
1887                 $raw = $wgCommandLineMode;
1888         }
1889
1890         if ( $raw ) {
1891                 $frameFormat = "%s line %s calls %s()\n";
1892                 $traceFormat = "%s";
1893         } else {
1894                 $frameFormat = "<li>%s line %s calls %s()</li>\n";
1895                 $traceFormat = "<ul>\n%s</ul>\n";
1896         }
1897
1898         $frames = array_map( function ( $frame ) use ( $frameFormat ) {
1899                 $file = !empty( $frame['file'] ) ? basename( $frame['file'] ) : '-';
1900                 $line = isset( $frame['line'] ) ? $frame['line'] : '-';
1901                 $call = $frame['function'];
1902                 if ( !empty( $frame['class'] ) ) {
1903                         $call = $frame['class'] . $frame['type'] . $call;
1904                 }
1905                 return sprintf( $frameFormat, $file, $line, $call );
1906         }, wfDebugBacktrace() );
1907
1908         return sprintf( $traceFormat, implode( '', $frames ) );
1909 }
1910
1911 /**
1912  * Get the name of the function which called this function
1913  * wfGetCaller( 1 ) is the function with the wfGetCaller() call (ie. __FUNCTION__)
1914  * wfGetCaller( 2 ) [default] is the caller of the function running wfGetCaller()
1915  * wfGetCaller( 3 ) is the parent of that.
1916  *
1917  * @param int $level
1918  * @return string
1919  */
1920 function wfGetCaller( $level = 2 ) {
1921         $backtrace = wfDebugBacktrace( $level + 1 );
1922         if ( isset( $backtrace[$level] ) ) {
1923                 return wfFormatStackFrame( $backtrace[$level] );
1924         } else {
1925                 return 'unknown';
1926         }
1927 }
1928
1929 /**
1930  * Return a string consisting of callers in the stack. Useful sometimes
1931  * for profiling specific points.
1932  *
1933  * @param int $limit The maximum depth of the stack frame to return, or false for the entire stack.
1934  * @return string
1935  */
1936 function wfGetAllCallers( $limit = 3 ) {
1937         $trace = array_reverse( wfDebugBacktrace() );
1938         if ( !$limit || $limit > count( $trace ) - 1 ) {
1939                 $limit = count( $trace ) - 1;
1940         }
1941         $trace = array_slice( $trace, -$limit - 1, $limit );
1942         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1943 }
1944
1945 /**
1946  * Return a string representation of frame
1947  *
1948  * @param array $frame
1949  * @return string
1950  */
1951 function wfFormatStackFrame( $frame ) {
1952         return isset( $frame['class'] ) ?
1953                 $frame['class'] . '::' . $frame['function'] :
1954                 $frame['function'];
1955 }
1956
1957 /* Some generic result counters, pulled out of SearchEngine */
1958
1959 /**
1960  * @todo document
1961  *
1962  * @param int $offset
1963  * @param int $limit
1964  * @return string
1965  */
1966 function wfShowingResults( $offset, $limit ) {
1967         return wfMessage( 'showingresults' )->numParams( $limit, $offset + 1 )->parse();
1968 }
1969
1970 /**
1971  * @todo document
1972  * @todo FIXME: We may want to blacklist some broken browsers
1973  *
1974  * @param bool $force
1975  * @return bool Whereas client accept gzip compression
1976  */
1977 function wfClientAcceptsGzip( $force = false ) {
1978         static $result = null;
1979         if ( $result === null || $force ) {
1980                 $result = false;
1981                 if ( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1982                         # @todo FIXME: We may want to blacklist some broken browsers
1983                         $m = array();
1984                         if ( preg_match(
1985                                         '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1986                                         $_SERVER['HTTP_ACCEPT_ENCODING'],
1987                                         $m
1988                                 )
1989                         ) {
1990                                 if ( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1991                                         $result = false;
1992                                         return $result;
1993                                 }
1994                                 wfDebug( "wfClientAcceptsGzip: client accepts gzip.\n" );
1995                                 $result = true;
1996                         }
1997                 }
1998         }
1999         return $result;
2000 }
2001
2002 /**
2003  * Obtain the offset and limit values from the request string;
2004  * used in special pages
2005  *
2006  * @param int $deflimit Default limit if none supplied
2007  * @param string $optionname Name of a user preference to check against
2008  * @return array
2009  * @deprecated since 1.24, just call WebRequest::getLimitOffset() directly
2010  */
2011 function wfCheckLimits( $deflimit = 50, $optionname = 'rclimit' ) {
2012         global $wgRequest;
2013         wfDeprecated( __METHOD__, '1.24' );
2014         return $wgRequest->getLimitOffset( $deflimit, $optionname );
2015 }
2016
2017 /**
2018  * Escapes the given text so that it may be output using addWikiText()
2019  * without any linking, formatting, etc. making its way through. This
2020  * is achieved by substituting certain characters with HTML entities.
2021  * As required by the callers, "<nowiki>" is not used.
2022  *
2023  * @param string $text Text to be escaped
2024  * @return string
2025  */
2026 function wfEscapeWikiText( $text ) {
2027         static $repl = null, $repl2 = null;
2028         if ( $repl === null ) {
2029                 $repl = array(
2030                         '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
2031                         '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
2032                         '{' => '&#123;', '|' => '&#124;', '}' => '&#125;', ';' => '&#59;',
2033                         "\n#" => "\n&#35;", "\r#" => "\r&#35;",
2034                         "\n*" => "\n&#42;", "\r*" => "\r&#42;",
2035                         "\n:" => "\n&#58;", "\r:" => "\r&#58;",
2036                         "\n " => "\n&#32;", "\r " => "\r&#32;",
2037                         "\n\n" => "\n&#10;", "\r\n" => "&#13;\n",
2038                         "\n\r" => "\n&#13;", "\r\r" => "\r&#13;",
2039                         "\n\t" => "\n&#9;", "\r\t" => "\r&#9;", // "\n\t\n" is treated like "\n\n"
2040                         "\n----" => "\n&#45;---", "\r----" => "\r&#45;---",
2041                         '__' => '_&#95;', '://' => '&#58;//',
2042                 );
2043
2044                 // We have to catch everything "\s" matches in PCRE
2045                 foreach ( array( 'ISBN', 'RFC', 'PMID' ) as $magic ) {
2046                         $repl["$magic "] = "$magic&#32;";
2047                         $repl["$magic\t"] = "$magic&#9;";
2048                         $repl["$magic\r"] = "$magic&#13;";
2049                         $repl["$magic\n"] = "$magic&#10;";
2050                         $repl["$magic\f"] = "$magic&#12;";
2051                 }
2052
2053                 // And handle protocols that don't use "://"
2054                 global $wgUrlProtocols;
2055                 $repl2 = array();
2056                 foreach ( $wgUrlProtocols as $prot ) {
2057                         if ( substr( $prot, -1 ) === ':' ) {
2058                                 $repl2[] = preg_quote( substr( $prot, 0, -1 ), '/' );
2059                         }
2060                 }
2061                 $repl2 = $repl2 ? '/\b(' . join( '|', $repl2 ) . '):/i' : '/^(?!)/';
2062         }
2063         $text = substr( strtr( "\n$text", $repl ), 1 );
2064         $text = preg_replace( $repl2, '$1&#58;', $text );
2065         return $text;
2066 }
2067
2068 /**
2069  * Sets dest to source and returns the original value of dest
2070  * If source is NULL, it just returns the value, it doesn't set the variable
2071  * If force is true, it will set the value even if source is NULL
2072  *
2073  * @param mixed $dest
2074  * @param mixed $source
2075  * @param bool $force
2076  * @return mixed
2077  */
2078 function wfSetVar( &$dest, $source, $force = false ) {
2079         $temp = $dest;
2080         if ( !is_null( $source ) || $force ) {
2081                 $dest = $source;
2082         }
2083         return $temp;
2084 }
2085
2086 /**
2087  * As for wfSetVar except setting a bit
2088  *
2089  * @param int $dest
2090  * @param int $bit
2091  * @param bool $state
2092  *
2093  * @return bool
2094  */
2095 function wfSetBit( &$dest, $bit, $state = true ) {
2096         $temp = (bool)( $dest & $bit );
2097         if ( !is_null( $state ) ) {
2098                 if ( $state ) {
2099                         $dest |= $bit;
2100                 } else {
2101                         $dest &= ~$bit;
2102                 }
2103         }
2104         return $temp;
2105 }
2106
2107 /**
2108  * A wrapper around the PHP function var_export().
2109  * Either print it or add it to the regular output ($wgOut).
2110  *
2111  * @param mixed $var A PHP variable to dump.
2112  */
2113 function wfVarDump( $var ) {
2114         global $wgOut;
2115         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
2116         if ( headers_sent() || !isset( $wgOut ) || !is_object( $wgOut ) ) {
2117                 print $s;
2118         } else {
2119                 $wgOut->addHTML( $s );
2120         }
2121 }
2122
2123 /**
2124  * Provide a simple HTTP error.
2125  *
2126  * @param int|string $code
2127  * @param string $label
2128  * @param string $desc
2129  */
2130 function wfHttpError( $code, $label, $desc ) {
2131         global $wgOut;
2132         HttpStatus::header( $code );
2133         if ( $wgOut ) {
2134                 $wgOut->disable();
2135                 $wgOut->sendCacheControl();
2136         }
2137
2138         header( 'Content-type: text/html; charset=utf-8' );
2139         print '<!DOCTYPE html>' .
2140                 '<html><head><title>' .
2141                 htmlspecialchars( $label ) .
2142                 '</title></head><body><h1>' .
2143                 htmlspecialchars( $label ) .
2144                 '</h1><p>' .
2145                 nl2br( htmlspecialchars( $desc ) ) .
2146                 "</p></body></html>\n";
2147 }
2148
2149 /**
2150  * Clear away any user-level output buffers, discarding contents.
2151  *
2152  * Suitable for 'starting afresh', for instance when streaming
2153  * relatively large amounts of data without buffering, or wanting to
2154  * output image files without ob_gzhandler's compression.
2155  *
2156  * The optional $resetGzipEncoding parameter controls suppression of
2157  * the Content-Encoding header sent by ob_gzhandler; by default it
2158  * is left. See comments for wfClearOutputBuffers() for why it would
2159  * be used.
2160  *
2161  * Note that some PHP configuration options may add output buffer
2162  * layers which cannot be removed; these are left in place.
2163  *
2164  * @param bool $resetGzipEncoding
2165  */
2166 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
2167         if ( $resetGzipEncoding ) {
2168                 // Suppress Content-Encoding and Content-Length
2169                 // headers from 1.10+s wfOutputHandler
2170                 global $wgDisableOutputCompression;
2171                 $wgDisableOutputCompression = true;
2172         }
2173         while ( $status = ob_get_status() ) {
2174                 if ( $status['type'] == 0 /* PHP_OUTPUT_HANDLER_INTERNAL */ ) {
2175                         // Probably from zlib.output_compression or other
2176                         // PHP-internal setting which can't be removed.
2177                         //
2178                         // Give up, and hope the result doesn't break
2179                         // output behavior.
2180                         break;
2181                 }
2182                 if ( !ob_end_clean() ) {
2183                         // Could not remove output buffer handler; abort now
2184                         // to avoid getting in some kind of infinite loop.
2185                         break;
2186                 }
2187                 if ( $resetGzipEncoding ) {
2188                         if ( $status['name'] == 'ob_gzhandler' ) {
2189                                 // Reset the 'Content-Encoding' field set by this handler
2190                                 // so we can start fresh.
2191                                 header_remove( 'Content-Encoding' );
2192                                 break;
2193                         }
2194                 }
2195         }
2196 }
2197
2198 /**
2199  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
2200  *
2201  * Clear away output buffers, but keep the Content-Encoding header
2202  * produced by ob_gzhandler, if any.
2203  *
2204  * This should be used for HTTP 304 responses, where you need to
2205  * preserve the Content-Encoding header of the real result, but
2206  * also need to suppress the output of ob_gzhandler to keep to spec
2207  * and avoid breaking Firefox in rare cases where the headers and
2208  * body are broken over two packets.
2209  */
2210 function wfClearOutputBuffers() {
2211         wfResetOutputBuffers( false );
2212 }
2213
2214 /**
2215  * Converts an Accept-* header into an array mapping string values to quality
2216  * factors
2217  *
2218  * @param string $accept
2219  * @param string $def Default
2220  * @return float[] Associative array of string => float pairs
2221  */
2222 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
2223         # No arg means accept anything (per HTTP spec)
2224         if ( !$accept ) {
2225                 return array( $def => 1.0 );
2226         }
2227
2228         $prefs = array();
2229
2230         $parts = explode( ',', $accept );
2231
2232         foreach ( $parts as $part ) {
2233                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
2234                 $values = explode( ';', trim( $part ) );
2235                 $match = array();
2236                 if ( count( $values ) == 1 ) {
2237                         $prefs[$values[0]] = 1.0;
2238                 } elseif ( preg_match( '/q\s*=\s*(\d*\.\d+)/', $values[1], $match ) ) {
2239                         $prefs[$values[0]] = floatval( $match[1] );
2240                 }
2241         }
2242
2243         return $prefs;
2244 }
2245
2246 /**
2247  * Checks if a given MIME type matches any of the keys in the given
2248  * array. Basic wildcards are accepted in the array keys.
2249  *
2250  * Returns the matching MIME type (or wildcard) if a match, otherwise
2251  * NULL if no match.
2252  *
2253  * @param string $type
2254  * @param array $avail
2255  * @return string
2256  * @private
2257  */
2258 function mimeTypeMatch( $type, $avail ) {
2259         if ( array_key_exists( $type, $avail ) ) {
2260                 return $type;
2261         } else {
2262                 $parts = explode( '/', $type );
2263                 if ( array_key_exists( $parts[0] . '/*', $avail ) ) {
2264                         return $parts[0] . '/*';
2265                 } elseif ( array_key_exists( '*/*', $avail ) ) {
2266                         return '*/*';
2267                 } else {
2268                         return null;
2269                 }
2270         }
2271 }
2272
2273 /**
2274  * Returns the 'best' match between a client's requested internet media types
2275  * and the server's list of available types. Each list should be an associative
2276  * array of type to preference (preference is a float between 0.0 and 1.0).
2277  * Wildcards in the types are acceptable.
2278  *
2279  * @param array $cprefs Client's acceptable type list
2280  * @param array $sprefs Server's offered types
2281  * @return string
2282  *
2283  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
2284  * XXX: generalize to negotiate other stuff
2285  */
2286 function wfNegotiateType( $cprefs, $sprefs ) {
2287         $combine = array();
2288
2289         foreach ( array_keys( $sprefs ) as $type ) {
2290                 $parts = explode( '/', $type );
2291                 if ( $parts[1] != '*' ) {
2292                         $ckey = mimeTypeMatch( $type, $cprefs );
2293                         if ( $ckey ) {
2294                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
2295                         }
2296                 }
2297         }
2298
2299         foreach ( array_keys( $cprefs ) as $type ) {
2300                 $parts = explode( '/', $type );
2301                 if ( $parts[1] != '*' && !array_key_exists( $type, $sprefs ) ) {
2302                         $skey = mimeTypeMatch( $type, $sprefs );
2303                         if ( $skey ) {
2304                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
2305                         }
2306                 }
2307         }
2308
2309         $bestq = 0;
2310         $besttype = null;
2311
2312         foreach ( array_keys( $combine ) as $type ) {
2313                 if ( $combine[$type] > $bestq ) {
2314                         $besttype = $type;
2315                         $bestq = $combine[$type];
2316                 }
2317         }
2318
2319         return $besttype;
2320 }
2321
2322 /**
2323  * Reference-counted warning suppression
2324  *
2325  * @deprecated since 1.26, use MediaWiki\suppressWarnings() directly
2326  * @param bool $end
2327  */
2328 function wfSuppressWarnings( $end = false ) {
2329         MediaWiki\suppressWarnings( $end );
2330 }
2331
2332 /**
2333  * @deprecated since 1.26, use MediaWiki\restoreWarnings() directly
2334  * Restore error level to previous value
2335  */
2336 function wfRestoreWarnings() {
2337         MediaWiki\suppressWarnings( true );
2338 }
2339
2340 # Autodetect, convert and provide timestamps of various types
2341
2342 /**
2343  * Unix time - the number of seconds since 1970-01-01 00:00:00 UTC
2344  */
2345 define( 'TS_UNIX', 0 );
2346
2347 /**
2348  * MediaWiki concatenated string timestamp (YYYYMMDDHHMMSS)
2349  */
2350 define( 'TS_MW', 1 );
2351
2352 /**
2353  * MySQL DATETIME (YYYY-MM-DD HH:MM:SS)
2354  */
2355 define( 'TS_DB', 2 );
2356
2357 /**
2358  * RFC 2822 format, for E-mail and HTTP headers
2359  */
2360 define( 'TS_RFC2822', 3 );
2361
2362 /**
2363  * ISO 8601 format with no timezone: 1986-02-09T20:00:00Z
2364  *
2365  * This is used by Special:Export
2366  */
2367 define( 'TS_ISO_8601', 4 );
2368
2369 /**
2370  * An Exif timestamp (YYYY:MM:DD HH:MM:SS)
2371  *
2372  * @see http://exif.org/Exif2-2.PDF The Exif 2.2 spec, see page 28 for the
2373  *       DateTime tag and page 36 for the DateTimeOriginal and
2374  *       DateTimeDigitized tags.
2375  */
2376 define( 'TS_EXIF', 5 );
2377
2378 /**
2379  * Oracle format time.
2380  */
2381 define( 'TS_ORACLE', 6 );
2382
2383 /**
2384  * Postgres format time.
2385  */
2386 define( 'TS_POSTGRES', 7 );
2387
2388 /**
2389  * ISO 8601 basic format with no timezone: 19860209T200000Z.  This is used by ResourceLoader
2390  */
2391 define( 'TS_ISO_8601_BASIC', 9 );
2392
2393 /**
2394  * Get a timestamp string in one of various formats
2395  *
2396  * @param mixed $outputtype A timestamp in one of the supported formats, the
2397  *   function will autodetect which format is supplied and act accordingly.
2398  * @param mixed $ts Optional timestamp to convert, default 0 for the current time
2399  * @return string|bool String / false The same date in the format specified in $outputtype or false
2400  */
2401 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
2402         try {
2403                 $timestamp = new MWTimestamp( $ts );
2404                 return $timestamp->getTimestamp( $outputtype );
2405         } catch ( TimestampException $e ) {
2406                 wfDebug( "wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n" );
2407                 return false;
2408         }
2409 }
2410
2411 /**
2412  * Return a formatted timestamp, or null if input is null.
2413  * For dealing with nullable timestamp columns in the database.
2414  *
2415  * @param int $outputtype
2416  * @param string $ts
2417  * @return string
2418  */
2419 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2420         if ( is_null( $ts ) ) {
2421                 return null;
2422         } else {
2423                 return wfTimestamp( $outputtype, $ts );
2424         }
2425 }
2426
2427 /**
2428  * Convenience function; returns MediaWiki timestamp for the present time.
2429  *
2430  * @return string
2431  */
2432 function wfTimestampNow() {
2433         # return NOW
2434         return wfTimestamp( TS_MW, time() );
2435 }
2436
2437 /**
2438  * Check if the operating system is Windows
2439  *
2440  * @return bool True if it's Windows, false otherwise.
2441  */
2442 function wfIsWindows() {
2443         static $isWindows = null;
2444         if ( $isWindows === null ) {
2445                 $isWindows = strtoupper( substr( PHP_OS, 0, 3 ) ) === 'WIN';
2446         }
2447         return $isWindows;
2448 }
2449
2450 /**
2451  * Check if we are running under HHVM
2452  *
2453  * @return bool
2454  */
2455 function wfIsHHVM() {
2456         return defined( 'HHVM_VERSION' );
2457 }
2458
2459 /**
2460  * Tries to get the system directory for temporary files. First
2461  * $wgTmpDirectory is checked, and then the TMPDIR, TMP, and TEMP
2462  * environment variables are then checked in sequence, and if none are
2463  * set try sys_get_temp_dir().
2464  *
2465  * NOTE: When possible, use instead the tmpfile() function to create
2466  * temporary files to avoid race conditions on file creation, etc.
2467  *
2468  * @return string
2469  */
2470 function wfTempDir() {
2471         global $wgTmpDirectory;
2472
2473         if ( $wgTmpDirectory !== false ) {
2474                 return $wgTmpDirectory;
2475         }
2476
2477         $tmpDir = array_map( "getenv", array( 'TMPDIR', 'TMP', 'TEMP' ) );
2478
2479         foreach ( $tmpDir as $tmp ) {
2480                 if ( $tmp && file_exists( $tmp ) && is_dir( $tmp ) && is_writable( $tmp ) ) {
2481                         return $tmp;
2482                 }
2483         }
2484         return sys_get_temp_dir();
2485 }
2486
2487 /**
2488  * Make directory, and make all parent directories if they don't exist
2489  *
2490  * @param string $dir Full path to directory to create
2491  * @param int $mode Chmod value to use, default is $wgDirectoryMode
2492  * @param string $caller Optional caller param for debugging.
2493  * @throws MWException
2494  * @return bool
2495  */
2496 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2497         global $wgDirectoryMode;
2498
2499         if ( FileBackend::isStoragePath( $dir ) ) { // sanity
2500                 throw new MWException( __FUNCTION__ . " given storage path '$dir'." );
2501         }
2502
2503         if ( !is_null( $caller ) ) {
2504                 wfDebug( "$caller: called wfMkdirParents($dir)\n" );
2505         }
2506
2507         if ( strval( $dir ) === '' || is_dir( $dir ) ) {
2508                 return true;
2509         }
2510
2511         $dir = str_replace( array( '\\', '/' ), DIRECTORY_SEPARATOR, $dir );
2512
2513         if ( is_null( $mode ) ) {
2514                 $mode = $wgDirectoryMode;
2515         }
2516
2517         // Turn off the normal warning, we're doing our own below
2518         MediaWiki\suppressWarnings();
2519         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2520         MediaWiki\restoreWarnings();
2521
2522         if ( !$ok ) {
2523                 //directory may have been created on another request since we last checked
2524                 if ( is_dir( $dir ) ) {
2525                         return true;
2526                 }
2527
2528                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2529                 wfLogWarning( sprintf( "failed to mkdir \"%s\" mode 0%o", $dir, $mode ) );
2530         }
2531         return $ok;
2532 }
2533
2534 /**
2535  * Remove a directory and all its content.
2536  * Does not hide error.
2537  * @param string $dir
2538  */
2539 function wfRecursiveRemoveDir( $dir ) {
2540         wfDebug( __FUNCTION__ . "( $dir )\n" );
2541         // taken from http://de3.php.net/manual/en/function.rmdir.php#98622
2542         if ( is_dir( $dir ) ) {
2543                 $objects = scandir( $dir );
2544                 foreach ( $objects as $object ) {
2545                         if ( $object != "." && $object != ".." ) {
2546                                 if ( filetype( $dir . '/' . $object ) == "dir" ) {
2547                                         wfRecursiveRemoveDir( $dir . '/' . $object );
2548                                 } else {
2549                                         unlink( $dir . '/' . $object );
2550                                 }
2551                         }
2552                 }
2553                 reset( $objects );
2554                 rmdir( $dir );
2555         }
2556 }
2557
2558 /**
2559  * @param int $nr The number to format
2560  * @param int $acc The number of digits after the decimal point, default 2
2561  * @param bool $round Whether or not to round the value, default true
2562  * @return string
2563  */
2564 function wfPercent( $nr, $acc = 2, $round = true ) {
2565         $ret = sprintf( "%.${acc}f", $nr );
2566         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2567 }
2568
2569 /**
2570  * Safety wrapper around ini_get() for boolean settings.
2571  * The values returned from ini_get() are pre-normalized for settings
2572  * set via php.ini or php_flag/php_admin_flag... but *not*
2573  * for those set via php_value/php_admin_value.
2574  *
2575  * It's fairly common for people to use php_value instead of php_flag,
2576  * which can leave you with an 'off' setting giving a false positive
2577  * for code that just takes the ini_get() return value as a boolean.
2578  *
2579  * To make things extra interesting, setting via php_value accepts
2580  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2581  * Unrecognized values go false... again opposite PHP's own coercion
2582  * from string to bool.
2583  *
2584  * Luckily, 'properly' set settings will always come back as '0' or '1',
2585  * so we only have to worry about them and the 'improper' settings.
2586  *
2587  * I frickin' hate PHP... :P
2588  *
2589  * @param string $setting
2590  * @return bool
2591  */
2592 function wfIniGetBool( $setting ) {
2593         $val = strtolower( ini_get( $setting ) );
2594         // 'on' and 'true' can't have whitespace around them, but '1' can.
2595         return $val == 'on'
2596                 || $val == 'true'
2597                 || $val == 'yes'
2598                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2599 }
2600
2601 /**
2602  * Windows-compatible version of escapeshellarg()
2603  * Windows doesn't recognise single-quotes in the shell, but the escapeshellarg()
2604  * function puts single quotes in regardless of OS.
2605  *
2606  * Also fixes the locale problems on Linux in PHP 5.2.6+ (bug backported to
2607  * earlier distro releases of PHP)
2608  *
2609  * @param string ... strings to escape and glue together, or a single array of strings parameter
2610  * @return string
2611  */
2612 function wfEscapeShellArg( /*...*/ ) {
2613         wfInitShellLocale();
2614
2615         $args = func_get_args();
2616         if ( count( $args ) === 1 && is_array( reset( $args ) ) ) {
2617                 // If only one argument has been passed, and that argument is an array,
2618                 // treat it as a list of arguments
2619                 $args = reset( $args );
2620         }
2621
2622         $first = true;
2623         $retVal = '';
2624         foreach ( $args as $arg ) {
2625                 if ( !$first ) {
2626                         $retVal .= ' ';
2627                 } else {
2628                         $first = false;
2629                 }
2630
2631                 if ( wfIsWindows() ) {
2632                         // Escaping for an MSVC-style command line parser and CMD.EXE
2633                         // @codingStandardsIgnoreStart For long URLs
2634                         // Refs:
2635                         //  * http://web.archive.org/web/20020708081031/http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
2636                         //  * http://technet.microsoft.com/en-us/library/cc723564.aspx
2637                         //  * Bug #13518
2638                         //  * CR r63214
2639                         // Double the backslashes before any double quotes. Escape the double quotes.
2640                         // @codingStandardsIgnoreEnd
2641                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
2642                         $arg = '';
2643                         $iteration = 0;
2644                         foreach ( $tokens as $token ) {
2645                                 if ( $iteration % 2 == 1 ) {
2646                                         // Delimiter, a double quote preceded by zero or more slashes
2647                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
2648                                 } elseif ( $iteration % 4 == 2 ) {
2649                                         // ^ in $token will be outside quotes, need to be escaped
2650                                         $arg .= str_replace( '^', '^^', $token );
2651                                 } else { // $iteration % 4 == 0
2652                                         // ^ in $token will appear inside double quotes, so leave as is
2653                                         $arg .= $token;
2654                                 }
2655                                 $iteration++;
2656                         }
2657                         // Double the backslashes before the end of the string, because
2658                         // we will soon add a quote
2659                         $m = array();
2660                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
2661                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
2662                         }
2663
2664                         // Add surrounding quotes
2665                         $retVal .= '"' . $arg . '"';
2666                 } else {
2667                         $retVal .= escapeshellarg( $arg );
2668                 }
2669         }
2670         return $retVal;
2671 }
2672
2673 /**
2674  * Check if wfShellExec() is effectively disabled via php.ini config
2675  *
2676  * @return bool|string False or one of (safemode,disabled)
2677  * @since 1.22
2678  */
2679 function wfShellExecDisabled() {
2680         static $disabled = null;
2681         if ( is_null( $disabled ) ) {
2682                 if ( wfIniGetBool( 'safe_mode' ) ) {
2683                         wfDebug( "wfShellExec can't run in safe_mode, PHP's exec functions are too broken.\n" );
2684                         $disabled = 'safemode';
2685                 } elseif ( !function_exists( 'proc_open' ) ) {
2686                         wfDebug( "proc_open() is disabled\n" );
2687                         $disabled = 'disabled';
2688                 } else {
2689                         $disabled = false;
2690                 }
2691         }
2692         return $disabled;
2693 }
2694
2695 /**
2696  * Execute a shell command, with time and memory limits mirrored from the PHP
2697  * configuration if supported.
2698  *
2699  * @param string|string[] $cmd If string, a properly shell-escaped command line,
2700  *   or an array of unescaped arguments, in which case each value will be escaped
2701  *   Example:   [ 'convert', '-font', 'font name' ] would produce "'convert' '-font' 'font name'"
2702  * @param null|mixed &$retval Optional, will receive the program's exit code.
2703  *   (non-zero is usually failure). If there is an error from
2704  *   read, select, or proc_open(), this will be set to -1.
2705  * @param array $environ Optional environment variables which should be
2706  *   added to the executed command environment.
2707  * @param array $limits Optional array with limits(filesize, memory, time, walltime)
2708  *   this overwrites the global wgMaxShell* limits.
2709  * @param array $options Array of options:
2710  *   - duplicateStderr: Set this to true to duplicate stderr to stdout,
2711  *     including errors from limit.sh
2712  *   - profileMethod: By default this function will profile based on the calling
2713  *     method. Set this to a string for an alternative method to profile from
2714  *
2715  * @return string Collected stdout as a string
2716  */
2717 function wfShellExec( $cmd, &$retval = null, $environ = array(),
2718         $limits = array(), $options = array()
2719 ) {
2720         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize, $wgMaxShellTime,
2721                 $wgMaxShellWallClockTime, $wgShellCgroup;
2722
2723         $disabled = wfShellExecDisabled();
2724         if ( $disabled ) {
2725                 $retval = 1;
2726                 return $disabled == 'safemode' ?
2727                         'Unable to run external programs in safe mode.' :
2728                         'Unable to run external programs, proc_open() is disabled.';
2729         }
2730
2731         $includeStderr = isset( $options['duplicateStderr'] ) && $options['duplicateStderr'];
2732         $profileMethod = isset( $options['profileMethod'] ) ? $options['profileMethod'] : wfGetCaller();
2733
2734         wfInitShellLocale();
2735
2736         $envcmd = '';
2737         foreach ( $environ as $k => $v ) {
2738                 if ( wfIsWindows() ) {
2739                         /* Surrounding a set in quotes (method used by wfEscapeShellArg) makes the quotes themselves
2740                          * appear in the environment variable, so we must use carat escaping as documented in
2741                          * http://technet.microsoft.com/en-us/library/cc723564.aspx
2742                          * Note however that the quote isn't listed there, but is needed, and the parentheses
2743                          * are listed there but doesn't appear to need it.
2744                          */
2745                         $envcmd .= "set $k=" . preg_replace( '/([&|()<>^"])/', '^\\1', $v ) . '&& ';
2746                 } else {
2747                         /* Assume this is a POSIX shell, thus required to accept variable assignments before the command
2748                          * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_09_01
2749                          */
2750                         $envcmd .= "$k=" . escapeshellarg( $v ) . ' ';
2751                 }
2752         }
2753         if ( is_array( $cmd ) ) {
2754                 $cmd = wfEscapeShellArg( $cmd );
2755         }
2756
2757         $cmd = $envcmd . $cmd;
2758
2759         $useLogPipe = false;
2760         if ( is_executable( '/bin/bash' ) ) {
2761                 $time = intval ( isset( $limits['time'] ) ? $limits['time'] : $wgMaxShellTime );
2762                 if ( isset( $limits['walltime'] ) ) {
2763                         $wallTime = intval( $limits['walltime'] );
2764                 } elseif ( isset( $limits['time'] ) ) {
2765                         $wallTime = $time;
2766                 } else {
2767                         $wallTime = intval( $wgMaxShellWallClockTime );
2768                 }
2769                 $mem = intval ( isset( $limits['memory'] ) ? $limits['memory'] : $wgMaxShellMemory );
2770                 $filesize = intval ( isset( $limits['filesize'] ) ? $limits['filesize'] : $wgMaxShellFileSize );
2771
2772                 if ( $time > 0 || $mem > 0 || $filesize > 0 || $wallTime > 0 ) {
2773                         $cmd = '/bin/bash ' . escapeshellarg( "$IP/includes/limit.sh" ) . ' ' .
2774                                 escapeshellarg( $cmd ) . ' ' .
2775                                 escapeshellarg(
2776                                         "MW_INCLUDE_STDERR=" . ( $includeStderr ? '1' : '' ) . ';' .
2777                                         "MW_CPU_LIMIT=$time; " .
2778                                         'MW_CGROUP=' . escapeshellarg( $wgShellCgroup ) . '; ' .
2779                                         "MW_MEM_LIMIT=$mem; " .
2780                                         "MW_FILE_SIZE_LIMIT=$filesize; " .
2781                                         "MW_WALL_CLOCK_LIMIT=$wallTime; " .
2782                                         "MW_USE_LOG_PIPE=yes"
2783                                 );
2784                         $useLogPipe = true;
2785                 } elseif ( $includeStderr ) {
2786                         $cmd .= ' 2>&1';
2787                 }
2788         } elseif ( $includeStderr ) {
2789                 $cmd .= ' 2>&1';
2790         }
2791         wfDebug( "wfShellExec: $cmd\n" );
2792
2793         $desc = array(
2794                 0 => array( 'file', 'php://stdin', 'r' ),
2795                 1 => array( 'pipe', 'w' ),
2796                 2 => array( 'file', 'php://stderr', 'w' ) );
2797         if ( $useLogPipe ) {
2798                 $desc[3] = array( 'pipe', 'w' );
2799         }
2800         $pipes = null;
2801         $scoped = Profiler::instance()->scopedProfileIn( __FUNCTION__ . '-' . $profileMethod );
2802         $proc = proc_open( $cmd, $desc, $pipes );
2803         if ( !$proc ) {
2804                 wfDebugLog( 'exec', "proc_open() failed: $cmd" );
2805                 $retval = -1;
2806                 return '';
2807         }
2808         $outBuffer = $logBuffer = '';
2809         $emptyArray = array();
2810         $status = false;
2811         $logMsg = false;
2812
2813         // According to the documentation, it is possible for stream_select()
2814         // to fail due to EINTR. I haven't managed to induce this in testing
2815         // despite sending various signals. If it did happen, the error
2816         // message would take the form:
2817         //
2818         // stream_select(): unable to select [4]: Interrupted system call (max_fd=5)
2819         //
2820         // where [4] is the value of the macro EINTR and "Interrupted system
2821         // call" is string which according to the Linux manual is "possibly"
2822         // localised according to LC_MESSAGES.
2823         $eintr = defined( 'SOCKET_EINTR' ) ? SOCKET_EINTR : 4;
2824         $eintrMessage = "stream_select(): unable to select [$eintr]";
2825
2826         // Build a table mapping resource IDs to pipe FDs to work around a
2827         // PHP 5.3 issue in which stream_select() does not preserve array keys
2828         // <https://bugs.php.net/bug.php?id=53427>.
2829         $fds = array();
2830         foreach ( $pipes as $fd => $pipe ) {
2831                 $fds[(int)$pipe] = $fd;
2832         }
2833
2834         $running = true;
2835         $timeout = null;
2836         $numReadyPipes = 0;
2837
2838         while ( $running === true || $numReadyPipes !== 0 ) {
2839                 if ( $running ) {
2840                         $status = proc_get_status( $proc );
2841                         // If the process has terminated, switch to nonblocking selects
2842                         // for getting any data still waiting to be read.
2843                         if ( !$status['running'] ) {
2844                                 $running = false;
2845                                 $timeout = 0;
2846                         }
2847                 }
2848
2849                 $readyPipes = $pipes;
2850
2851                 // Clear last error
2852                 // @codingStandardsIgnoreStart Generic.PHP.NoSilencedErrors.Discouraged
2853                 @trigger_error( '' );
2854                 $numReadyPipes = @stream_select( $readyPipes, $emptyArray, $emptyArray, $timeout );
2855                 if ( $numReadyPipes === false ) {
2856                         // @codingStandardsIgnoreEnd
2857                         $error = error_get_last();
2858                         if ( strncmp( $error['message'], $eintrMessage, strlen( $eintrMessage ) ) == 0 ) {
2859                                 continue;
2860                         } else {
2861                                 trigger_error( $error['message'], E_USER_WARNING );
2862                                 $logMsg = $error['message'];
2863                                 break;
2864                         }
2865                 }
2866                 foreach ( $readyPipes as $pipe ) {
2867                         $block = fread( $pipe, 65536 );
2868                         $fd = $fds[(int)$pipe];
2869                         if ( $block === '' ) {
2870                                 // End of file
2871                                 fclose( $pipes[$fd] );
2872                                 unset( $pipes[$fd] );
2873                                 if ( !$pipes ) {
2874                                         break 2;
2875                                 }
2876                         } elseif ( $block === false ) {
2877                                 // Read error
2878                                 $logMsg = "Error reading from pipe";
2879                                 break 2;
2880                         } elseif ( $fd == 1 ) {
2881                                 // From stdout
2882                                 $outBuffer .= $block;
2883                         } elseif ( $fd == 3 ) {
2884                                 // From log FD
2885                                 $logBuffer .= $block;
2886                                 if ( strpos( $block, "\n" ) !== false ) {
2887                                         $lines = explode( "\n", $logBuffer );
2888                                         $logBuffer = array_pop( $lines );
2889                                         foreach ( $lines as $line ) {
2890                                                 wfDebugLog( 'exec', $line );
2891                                         }
2892                                 }
2893                         }
2894                 }
2895         }
2896
2897         foreach ( $pipes as $pipe ) {
2898                 fclose( $pipe );
2899         }
2900
2901         // Use the status previously collected if possible, since proc_get_status()
2902         // just calls waitpid() which will not return anything useful the second time.
2903         if ( $running ) {
2904                 $status = proc_get_status( $proc );
2905         }
2906
2907         if ( $logMsg !== false ) {
2908                 // Read/select error
2909                 $retval = -1;
2910                 proc_close( $proc );
2911         } elseif ( $status['signaled'] ) {
2912                 $logMsg = "Exited with signal {$status['termsig']}";
2913                 $retval = 128 + $status['termsig'];
2914                 proc_close( $proc );
2915         } else {
2916                 if ( $status['running'] ) {
2917                         $retval = proc_close( $proc );
2918                 } else {
2919                         $retval = $status['exitcode'];
2920                         proc_close( $proc );
2921                 }
2922                 if ( $retval == 127 ) {
2923                         $logMsg = "Possibly missing executable file";
2924                 } elseif ( $retval >= 129 && $retval <= 192 ) {
2925                         $logMsg = "Probably exited with signal " . ( $retval - 128 );
2926                 }
2927         }
2928
2929         if ( $logMsg !== false ) {
2930                 wfDebugLog( 'exec', "$logMsg: $cmd" );
2931         }
2932
2933         return $outBuffer;
2934 }
2935
2936 /**
2937  * Execute a shell command, returning both stdout and stderr. Convenience
2938  * function, as all the arguments to wfShellExec can become unwieldy.
2939  *
2940  * @note This also includes errors from limit.sh, e.g. if $wgMaxShellFileSize is exceeded.
2941  * @param string|string[] $cmd If string, a properly shell-escaped command line,
2942  *   or an array of unescaped arguments, in which case each value will be escaped
2943  *   Example:   [ 'convert', '-font', 'font name' ] would produce "'convert' '-font' 'font name'"
2944  * @param null|mixed &$retval Optional, will receive the program's exit code.
2945  *   (non-zero is usually failure)
2946  * @param array $environ Optional environment variables which should be
2947  *   added to the executed command environment.
2948  * @param array $limits Optional array with limits(filesize, memory, time, walltime)
2949  *   this overwrites the global wgMaxShell* limits.
2950  * @return string Collected stdout and stderr as a string
2951  */
2952 function wfShellExecWithStderr( $cmd, &$retval = null, $environ = array(), $limits = array() ) {
2953         return wfShellExec( $cmd, $retval, $environ, $limits,
2954                 array( 'duplicateStderr' => true, 'profileMethod' => wfGetCaller() ) );
2955 }
2956
2957 /**
2958  * Workaround for http://bugs.php.net/bug.php?id=45132
2959  * escapeshellarg() destroys non-ASCII characters if LANG is not a UTF-8 locale
2960  */
2961 function wfInitShellLocale() {
2962         static $done = false;
2963         if ( $done ) {
2964                 return;
2965         }
2966         $done = true;
2967         global $wgShellLocale;
2968         if ( !wfIniGetBool( 'safe_mode' ) ) {
2969                 putenv( "LC_CTYPE=$wgShellLocale" );
2970                 setlocale( LC_CTYPE, $wgShellLocale );
2971         }
2972 }
2973
2974 /**
2975  * Generate a shell-escaped command line string to run a MediaWiki cli script.
2976  * Note that $parameters should be a flat array and an option with an argument
2977  * should consist of two consecutive items in the array (do not use "--option value").
2978  *
2979  * @param string $script MediaWiki cli script path
2980  * @param array $parameters Arguments and options to the script
2981  * @param array $options Associative array of options:
2982  *              'php': The path to the php executable
2983  *              'wrapper': Path to a PHP wrapper to handle the maintenance script
2984  * @return string
2985  */
2986 function wfShellWikiCmd( $script, array $parameters = array(), array $options = array() ) {
2987         global $wgPhpCli;
2988         // Give site config file a chance to run the script in a wrapper.
2989         // The caller may likely want to call wfBasename() on $script.
2990         Hooks::run( 'wfShellWikiCmd', array( &$script, &$parameters, &$options ) );
2991         $cmd = isset( $options['php'] ) ? array( $options['php'] ) : array( $wgPhpCli );
2992         if ( isset( $options['wrapper'] ) ) {
2993                 $cmd[] = $options['wrapper'];
2994         }
2995         $cmd[] = $script;
2996         // Escape each parameter for shell
2997         return wfEscapeShellArg( array_merge( $cmd, $parameters ) );
2998 }
2999
3000 /**
3001  * wfMerge attempts to merge differences between three texts.
3002  * Returns true for a clean merge and false for failure or a conflict.
3003  *
3004  * @param string $old
3005  * @param string $mine
3006  * @param string $yours
3007  * @param string $result
3008  * @return bool
3009  */
3010 function wfMerge( $old, $mine, $yours, &$result ) {
3011         global $wgDiff3;
3012
3013         # This check may also protect against code injection in
3014         # case of broken installations.
3015         MediaWiki\suppressWarnings();
3016         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
3017         MediaWiki\restoreWarnings();
3018
3019         if ( !$haveDiff3 ) {
3020                 wfDebug( "diff3 not found\n" );
3021                 return false;
3022         }
3023
3024         # Make temporary files
3025         $td = wfTempDir();
3026         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
3027         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
3028         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
3029
3030         # NOTE: diff3 issues a warning to stderr if any of the files does not end with
3031         #       a newline character. To avoid this, we normalize the trailing whitespace before
3032         #       creating the diff.
3033
3034         fwrite( $oldtextFile, rtrim( $old ) . "\n" );
3035         fclose( $oldtextFile );
3036         fwrite( $mytextFile, rtrim( $mine ) . "\n" );
3037         fclose( $mytextFile );
3038         fwrite( $yourtextFile, rtrim( $yours ) . "\n" );
3039         fclose( $yourtextFile );
3040
3041         # Check for a conflict
3042         $cmd = wfEscapeShellArg( $wgDiff3, '-a', '--overlap-only', $mytextName,
3043                 $oldtextName, $yourtextName );
3044         $handle = popen( $cmd, 'r' );
3045
3046         if ( fgets( $handle, 1024 ) ) {
3047                 $conflict = true;
3048         } else {
3049                 $conflict = false;
3050         }
3051         pclose( $handle );
3052
3053         # Merge differences
3054         $cmd = wfEscapeShellArg( $wgDiff3, '-a', '-e', '--merge', $mytextName,
3055                 $oldtextName, $yourtextName );
3056         $handle = popen( $cmd, 'r' );
3057         $result = '';
3058         do {
3059                 $data = fread( $handle, 8192 );
3060                 if ( strlen( $data ) == 0 ) {
3061                         break;
3062                 }
3063                 $result .= $data;
3064         } while ( true );
3065         pclose( $handle );
3066         unlink( $mytextName );
3067         unlink( $oldtextName );
3068         unlink( $yourtextName );
3069
3070         if ( $result === '' && $old !== '' && !$conflict ) {
3071                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
3072                 $conflict = true;
3073         }
3074         return !$conflict;
3075 }
3076
3077 /**
3078  * Returns unified plain-text diff of two texts.
3079  * "Useful" for machine processing of diffs.
3080  *
3081  * @deprecated since 1.25, use DiffEngine/UnifiedDiffFormatter directly
3082  *
3083  * @param string $before The text before the changes.
3084  * @param string $after The text after the changes.
3085  * @param string $params Command-line options for the diff command.
3086  * @return string Unified diff of $before and $after
3087  */
3088 function wfDiff( $before, $after, $params = '-u' ) {
3089         if ( $before == $after ) {
3090                 return '';
3091         }
3092
3093         global $wgDiff;
3094         MediaWiki\suppressWarnings();
3095         $haveDiff = $wgDiff && file_exists( $wgDiff );
3096         MediaWiki\restoreWarnings();
3097
3098         # This check may also protect against code injection in
3099         # case of broken installations.
3100         if ( !$haveDiff ) {
3101                 wfDebug( "diff executable not found\n" );
3102                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
3103                 $format = new UnifiedDiffFormatter();
3104                 return $format->format( $diffs );
3105         }
3106
3107         # Make temporary files
3108         $td = wfTempDir();
3109         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
3110         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
3111
3112         fwrite( $oldtextFile, $before );
3113         fclose( $oldtextFile );
3114         fwrite( $newtextFile, $after );
3115         fclose( $newtextFile );
3116
3117         // Get the diff of the two files
3118         $cmd = "$wgDiff " . $params . ' ' . wfEscapeShellArg( $oldtextName, $newtextName );
3119
3120         $h = popen( $cmd, 'r' );
3121         if ( !$h ) {
3122                 unlink( $oldtextName );
3123                 unlink( $newtextName );
3124                 throw new Exception( __METHOD__ . '(): popen() failed' );
3125         }
3126
3127         $diff = '';
3128
3129         do {
3130                 $data = fread( $h, 8192 );
3131                 if ( strlen( $data ) == 0 ) {
3132                         break;
3133                 }
3134                 $diff .= $data;
3135         } while ( true );
3136
3137         // Clean up
3138         pclose( $h );
3139         unlink( $oldtextName );
3140         unlink( $newtextName );
3141
3142         // Kill the --- and +++ lines. They're not useful.
3143         $diff_lines = explode( "\n", $diff );
3144         if ( isset( $diff_lines[0] ) && strpos( $diff_lines[0], '---' ) === 0 ) {
3145                 unset( $diff_lines[0] );
3146         }
3147         if ( isset( $diff_lines[1] ) && strpos( $diff_lines[1], '+++' ) === 0 ) {
3148                 unset( $diff_lines[1] );
3149         }
3150
3151         $diff = implode( "\n", $diff_lines );
3152
3153         return $diff;
3154 }
3155
3156 /**
3157  * This function works like "use VERSION" in Perl, the program will die with a
3158  * backtrace if the current version of PHP is less than the version provided
3159  *
3160  * This is useful for extensions which due to their nature are not kept in sync
3161  * with releases, and might depend on other versions of PHP than the main code
3162  *
3163  * Note: PHP might die due to parsing errors in some cases before it ever
3164  *       manages to call this function, such is life
3165  *
3166  * @see perldoc -f use
3167  *
3168  * @param string|int|float $req_ver The version to check, can be a string, an integer, or a float
3169  * @throws MWException
3170  */
3171 function wfUsePHP( $req_ver ) {
3172         $php_ver = PHP_VERSION;
3173
3174         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
3175                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
3176         }
3177 }
3178
3179 /**
3180  * This function works like "use VERSION" in Perl except it checks the version
3181  * of MediaWiki, the program will die with a backtrace if the current version
3182  * of MediaWiki is less than the version provided.
3183  *
3184  * This is useful for extensions which due to their nature are not kept in sync
3185  * with releases
3186  *
3187  * Note: Due to the behavior of PHP's version_compare() which is used in this
3188  * function, if you want to allow the 'wmf' development versions add a 'c' (or
3189  * any single letter other than 'a', 'b' or 'p') as a post-fix to your
3190  * targeted version number. For example if you wanted to allow any variation
3191  * of 1.22 use `wfUseMW( '1.22c' )`. Using an 'a' or 'b' instead of 'c' will
3192  * not result in the same comparison due to the internal logic of
3193  * version_compare().
3194  *
3195  * @see perldoc -f use
3196  *
3197  * @param string|int|float $req_ver The version to check, can be a string, an integer, or a float
3198  * @throws MWException
3199  */
3200 function wfUseMW( $req_ver ) {
3201         global $wgVersion;
3202
3203         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
3204                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
3205         }
3206 }
3207
3208 /**
3209  * Return the final portion of a pathname.
3210  * Reimplemented because PHP5's "basename()" is buggy with multibyte text.
3211  * http://bugs.php.net/bug.php?id=33898
3212  *
3213  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
3214  * We'll consider it so always, as we don't want '\s' in our Unix paths either.
3215  *
3216  * @param string $path
3217  * @param string $suffix String to remove if present
3218  * @return string
3219  */
3220 function wfBaseName( $path, $suffix = '' ) {
3221         if ( $suffix == '' ) {
3222                 $encSuffix = '';
3223         } else {
3224                 $encSuffix = '(?:' . preg_quote( $suffix, '#' ) . ')?';
3225         }
3226
3227         $matches = array();
3228         if ( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
3229                 return $matches[1];
3230         } else {
3231                 return '';
3232         }
3233 }
3234
3235 /**
3236  * Generate a relative path name to the given file.
3237  * May explode on non-matching case-insensitive paths,
3238  * funky symlinks, etc.
3239  *
3240  * @param string $path Absolute destination path including target filename
3241  * @param string $from Absolute source path, directory only
3242  * @return string
3243  */
3244 function wfRelativePath( $path, $from ) {
3245         // Normalize mixed input on Windows...
3246         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
3247         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
3248
3249         // Trim trailing slashes -- fix for drive root
3250         $path = rtrim( $path, DIRECTORY_SEPARATOR );
3251         $from = rtrim( $from, DIRECTORY_SEPARATOR );
3252
3253         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
3254         $against = explode( DIRECTORY_SEPARATOR, $from );
3255
3256         if ( $pieces[0] !== $against[0] ) {
3257                 // Non-matching Windows drive letters?
3258                 // Return a full path.
3259                 return $path;
3260         }
3261
3262         // Trim off common prefix
3263         while ( count( $pieces ) && count( $against )
3264                 && $pieces[0] == $against[0] ) {
3265                 array_shift( $pieces );
3266                 array_shift( $against );
3267         }
3268
3269         // relative dots to bump us to the parent
3270         while ( count( $against ) ) {
3271                 array_unshift( $pieces, '..' );
3272                 array_shift( $against );
3273         }
3274
3275         array_push( $pieces, wfBaseName( $path ) );
3276
3277         return implode( DIRECTORY_SEPARATOR, $pieces );
3278 }
3279
3280 /**
3281  * Convert an arbitrarily-long digit string from one numeric base
3282  * to another, optionally zero-padding to a minimum column width.
3283  *
3284  * Supports base 2 through 36; digit values 10-36 are represented
3285  * as lowercase letters a-z. Input is case-insensitive.
3286  *
3287  * @param string $input Input number
3288  * @param int $sourceBase Base of the input number
3289  * @param int $destBase Desired base of the output
3290  * @param int $pad Minimum number of digits in the output (pad with zeroes)
3291  * @param bool $lowercase Whether to output in lowercase or uppercase
3292  * @param string $engine Either "gmp", "bcmath", or "php"
3293  * @return string|bool The output number as a string, or false on error
3294  */
3295 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1,
3296         $lowercase = true, $engine = 'auto'
3297 ) {
3298         $input = (string)$input;
3299         if (
3300                 $sourceBase < 2 ||
3301                 $sourceBase > 36 ||
3302                 $destBase < 2 ||
3303                 $destBase > 36 ||
3304                 $sourceBase != (int)$sourceBase ||
3305                 $destBase != (int)$destBase ||
3306                 $pad != (int)$pad ||
3307                 !preg_match(
3308                         "/^[" . substr( '0123456789abcdefghijklmnopqrstuvwxyz', 0, $sourceBase ) . "]+$/i",
3309                         $input
3310                 )
3311         ) {
3312                 return false;
3313         }
3314
3315         static $baseChars = array(
3316                 10 => 'a', 11 => 'b', 12 => 'c', 13 => 'd', 14 => 'e', 15 => 'f',
3317                 16 => 'g', 17 => 'h', 18 => 'i', 19 => 'j', 20 => 'k', 21 => 'l',
3318                 22 => 'm', 23 => 'n', 24 => 'o', 25 => 'p', 26 => 'q', 27 => 'r',
3319                 28 => 's', 29 => 't', 30 => 'u', 31 => 'v', 32 => 'w', 33 => 'x',
3320                 34 => 'y', 35 => 'z',
3321
3322                 '0' => 0, '1' => 1, '2' => 2, '3' => 3, '4' => 4, '5' => 5,
3323                 '6' => 6, '7' => 7, '8' => 8, '9' => 9, 'a' => 10, 'b' => 11,
3324                 'c' => 12, 'd' => 13, 'e' => 14, 'f' => 15, 'g' => 16, 'h' => 17,
3325                 'i' => 18, 'j' => 19, 'k' => 20, 'l' => 21, 'm' => 22, 'n' => 23,
3326                 'o' => 24, 'p' => 25, 'q' => 26, 'r' => 27, 's' => 28, 't' => 29,
3327                 'u' => 30, 'v' => 31, 'w' => 32, 'x' => 33, 'y' => 34, 'z' => 35
3328         );
3329
3330         if ( extension_loaded( 'gmp' ) && ( $engine == 'auto' || $engine == 'gmp' ) ) {
3331                 // Removing leading zeros works around broken base detection code in
3332                 // some PHP versions (see <https://bugs.php.net/bug.php?id=50175> and
3333                 // <https://bugs.php.net/bug.php?id=55398>).
3334                 $result = gmp_strval( gmp_init( ltrim( $input, '0' ) ?: '0', $sourceBase ), $destBase );
3335         } elseif ( extension_loaded( 'bcmath' ) && ( $engine == 'auto' || $engine == 'bcmath' ) ) {
3336                 $decimal = '0';
3337                 foreach ( str_split( strtolower( $input ) ) as $char ) {
3338                         $decimal = bcmul( $decimal, $sourceBase );
3339                         $decimal = bcadd( $decimal, $baseChars[$char] );
3340                 }
3341
3342                 // @codingStandardsIgnoreStart Generic.CodeAnalysis.ForLoopWithTestFunctionCall.NotAllowed
3343                 for ( $result = ''; bccomp( $decimal, 0 ); $decimal = bcdiv( $decimal, $destBase, 0 ) ) {
3344                         $result .= $baseChars[bcmod( $decimal, $destBase )];
3345                 }
3346                 // @codingStandardsIgnoreEnd
3347
3348                 $result = strrev( $result );
3349         } else {
3350                 $inDigits = array();
3351                 foreach ( str_split( strtolower( $input ) ) as $char ) {
3352                         $inDigits[] = $baseChars[$char];
3353                 }
3354
3355                 // Iterate over the input, modulo-ing out an output digit
3356                 // at a time until input is gone.
3357                 $result = '';
3358                 while ( $inDigits ) {
3359                         $work = 0;
3360                         $workDigits = array();
3361
3362                         // Long division...
3363                         foreach ( $inDigits as $digit ) {
3364                                 $work *= $sourceBase;
3365                                 $work += $digit;
3366
3367                                 if ( $workDigits || $work >= $destBase ) {
3368                                         $workDigits[] = (int)( $work / $destBase );
3369                                 }
3370                                 $work %= $destBase;
3371                         }
3372
3373                         // All that division leaves us with a remainder,
3374                         // which is conveniently our next output digit.
3375                         $result .= $baseChars[$work];
3376
3377                         // And we continue!
3378                         $inDigits = $workDigits;
3379                 }
3380
3381                 $result = strrev( $result );
3382         }
3383
3384         if ( !$lowercase ) {
3385                 $result = strtoupper( $result );
3386         }
3387
3388         return str_pad( $result, $pad, '0', STR_PAD_LEFT );
3389 }
3390
3391 /**
3392  * Check if there is sufficient entropy in php's built-in session generation
3393  *
3394  * @return bool True = there is sufficient entropy
3395  */
3396 function wfCheckEntropy() {
3397         return (
3398                         ( wfIsWindows() && version_compare( PHP_VERSION, '5.3.3', '>=' ) )
3399                         || ini_get( 'session.entropy_file' )
3400                 )
3401                 && intval( ini_get( 'session.entropy_length' ) ) >= 32;
3402 }
3403
3404 /**
3405  * Override session_id before session startup if php's built-in
3406  * session generation code is not secure.
3407  */
3408 function wfFixSessionID() {
3409         // If the cookie or session id is already set we already have a session and should abort
3410         if ( isset( $_COOKIE[session_name()] ) || session_id() ) {
3411                 return;
3412         }
3413
3414         // PHP's built-in session entropy is enabled if:
3415         // - entropy_file is set or you're on Windows with php 5.3.3+
3416         // - AND entropy_length is > 0
3417         // We treat it as disabled if it doesn't have an entropy length of at least 32
3418         $entropyEnabled = wfCheckEntropy();
3419
3420         // If built-in entropy is not enabled or not sufficient override PHP's
3421         // built in session id generation code
3422         if ( !$entropyEnabled ) {
3423                 wfDebug( __METHOD__ . ": PHP's built in entropy is disabled or not sufficient, " .
3424                         "overriding session id generation using our cryptrand source.\n" );
3425                 session_id( MWCryptRand::generateHex( 32 ) );
3426         }
3427 }
3428
3429 /**
3430  * Reset the session_id
3431  *
3432  * @since 1.22
3433  */
3434 function wfResetSessionID() {
3435         global $wgCookieSecure;
3436         $oldSessionId = session_id();
3437         $cookieParams = session_get_cookie_params();
3438         if ( wfCheckEntropy() && $wgCookieSecure == $cookieParams['secure'] ) {
3439                 session_regenerate_id( false );
3440         } else {
3441                 $tmp = $_SESSION;
3442                 session_destroy();
3443                 wfSetupSession( MWCryptRand::generateHex( 32 ) );
3444                 $_SESSION = $tmp;
3445         }
3446         $newSessionId = session_id();
3447         Hooks::run( 'ResetSessionID', array( $oldSessionId, $newSessionId ) );
3448 }
3449
3450 /**
3451  * Initialise php session
3452  *
3453  * @param bool $sessionId
3454  */
3455 function wfSetupSession( $sessionId = false ) {
3456         global $wgSessionsInMemcached, $wgSessionsInObjectCache, $wgCookiePath, $wgCookieDomain,
3457                         $wgCookieSecure, $wgCookieHttpOnly, $wgSessionHandler;
3458         if ( $wgSessionsInObjectCache || $wgSessionsInMemcached ) {
3459                 ObjectCacheSessionHandler::install();
3460         } elseif ( $wgSessionHandler && $wgSessionHandler != ini_get( 'session.save_handler' ) ) {
3461                 # Only set this if $wgSessionHandler isn't null and session.save_handler
3462                 # hasn't already been set to the desired value (that causes errors)
3463                 ini_set( 'session.save_handler', $wgSessionHandler );
3464         }
3465         session_set_cookie_params(
3466                 0, $wgCookiePath, $wgCookieDomain, $wgCookieSecure, $wgCookieHttpOnly );
3467         session_cache_limiter( 'private, must-revalidate' );
3468         if ( $sessionId ) {
3469                 session_id( $sessionId );
3470         } else {
3471                 wfFixSessionID();
3472         }
3473         MediaWiki\suppressWarnings();
3474         session_start();
3475         MediaWiki\restoreWarnings();
3476 }
3477
3478 /**
3479  * Get an object from the precompiled serialized directory
3480  *
3481  * @param string $name
3482  * @return mixed The variable on success, false on failure
3483  */
3484 function wfGetPrecompiledData( $name ) {
3485         global $IP;
3486
3487         $file = "$IP/serialized/$name";
3488         if ( file_exists( $file ) ) {
3489                 $blob = file_get_contents( $file );
3490                 if ( $blob ) {
3491                         return unserialize( $blob );
3492                 }
3493         }
3494         return false;
3495 }
3496
3497 /**
3498  * Get a cache key
3499  *
3500  * @param string $args,...
3501  * @return string
3502  */
3503 function wfMemcKey( /*...*/ ) {
3504         global $wgCachePrefix;
3505         $prefix = $wgCachePrefix === false ? wfWikiID() : $wgCachePrefix;
3506         $args = func_get_args();
3507         $key = $prefix . ':' . implode( ':', $args );
3508         $key = str_replace( ' ', '_', $key );
3509         return $key;
3510 }
3511
3512 /**
3513  * Get a cache key for a foreign DB
3514  *
3515  * @param string $db
3516  * @param string $prefix
3517  * @param string $args,...
3518  * @return string
3519  */
3520 function wfForeignMemcKey( $db, $prefix /*...*/ ) {
3521         $args = array_slice( func_get_args(), 2 );
3522         if ( $prefix ) {
3523                 $key = "$db-$prefix:" . implode( ':', $args );
3524         } else {
3525                 $key = $db . ':' . implode( ':', $args );
3526         }
3527         return str_replace( ' ', '_', $key );
3528 }
3529
3530 /**
3531  * Get an ASCII string identifying this wiki
3532  * This is used as a prefix in memcached keys
3533  *
3534  * @return string
3535  */
3536 function wfWikiID() {
3537         global $wgDBprefix, $wgDBname;
3538         if ( $wgDBprefix ) {
3539                 return "$wgDBname-$wgDBprefix";
3540         } else {
3541                 return $wgDBname;
3542         }
3543 }
3544
3545 /**
3546  * Split a wiki ID into DB name and table prefix
3547  *
3548  * @param string $wiki
3549  *
3550  * @return array
3551  */
3552 function wfSplitWikiID( $wiki ) {
3553         $bits = explode( '-', $wiki, 2 );
3554         if ( count( $bits ) < 2 ) {
3555                 $bits[] = '';
3556         }
3557         return $bits;
3558 }
3559
3560 /**
3561  * Get a Database object.
3562  *
3563  * @param int $db Index of the connection to get. May be DB_MASTER for the
3564  *            master (for write queries), DB_SLAVE for potentially lagged read
3565  *            queries, or an integer >= 0 for a particular server.
3566  *
3567  * @param string|string[] $groups Query groups. An array of group names that this query
3568  *                belongs to. May contain a single string if the query is only
3569  *                in one group.
3570  *
3571  * @param string|bool $wiki The wiki ID, or false for the current wiki
3572  *
3573  * Note: multiple calls to wfGetDB(DB_SLAVE) during the course of one request
3574  * will always return the same object, unless the underlying connection or load
3575  * balancer is manually destroyed.
3576  *
3577  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
3578  * updater to ensure that a proper database is being updated.
3579  *
3580  * @return DatabaseBase
3581  */
3582 function wfGetDB( $db, $groups = array(), $wiki = false ) {
3583         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
3584 }
3585
3586 /**
3587  * Get a load balancer object.
3588  *
3589  * @param string|bool $wiki Wiki ID, or false for the current wiki
3590  * @return LoadBalancer
3591  */
3592 function wfGetLB( $wiki = false ) {
3593         return wfGetLBFactory()->getMainLB( $wiki );
3594 }
3595
3596 /**
3597  * Get the load balancer factory object
3598  *
3599  * @return LBFactory
3600  */
3601 function wfGetLBFactory() {
3602         return LBFactory::singleton();
3603 }
3604
3605 /**
3606  * Find a file.
3607  * Shortcut for RepoGroup::singleton()->findFile()
3608  *
3609  * @param string $title String or Title object
3610  * @param array $options Associative array of options (see RepoGroup::findFile)
3611  * @return File|bool File, or false if the file does not exist
3612  */
3613 function wfFindFile( $title, $options = array() ) {
3614         return RepoGroup::singleton()->findFile( $title, $options );
3615 }
3616
3617 /**
3618  * Get an object referring to a locally registered file.
3619  * Returns a valid placeholder object if the file does not exist.
3620  *
3621  * @param Title|string $title
3622  * @return LocalFile|null A File, or null if passed an invalid Title
3623  */
3624 function wfLocalFile( $title ) {
3625         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
3626 }
3627
3628 /**
3629  * Should low-performance queries be disabled?
3630  *
3631  * @return bool
3632  * @codeCoverageIgnore
3633  */
3634 function wfQueriesMustScale() {
3635         global $wgMiserMode;
3636         return $wgMiserMode
3637                 || ( SiteStats::pages() > 100000
3638                 && SiteStats::edits() > 1000000
3639                 && SiteStats::users() > 10000 );
3640 }
3641
3642 /**
3643  * Get the path to a specified script file, respecting file
3644  * extensions; this is a wrapper around $wgScriptExtension etc.
3645  * except for 'index' and 'load' which use $wgScript/$wgLoadScript
3646  *
3647  * @param string $script Script filename, sans extension
3648  * @return string
3649  */
3650 function wfScript( $script = 'index' ) {
3651         global $wgScriptPath, $wgScriptExtension, $wgScript, $wgLoadScript;
3652         if ( $script === 'index' ) {
3653                 return $wgScript;
3654         } elseif ( $script === 'load' ) {
3655                 return $wgLoadScript;
3656         } else {
3657                 return "{$wgScriptPath}/{$script}{$wgScriptExtension}";
3658         }
3659 }
3660
3661 /**
3662  * Get the script URL.
3663  *
3664  * @return string Script URL
3665  */
3666 function wfGetScriptUrl() {
3667         if ( isset( $_SERVER['SCRIPT_NAME'] ) ) {
3668                 #
3669                 # as it was called, minus the query string.
3670                 #
3671                 # Some sites use Apache rewrite rules to handle subdomains,
3672                 # and have PHP set up in a weird way that causes PHP_SELF
3673                 # to contain the rewritten URL instead of the one that the
3674                 # outside world sees.
3675                 #
3676                 # If in this mode, use SCRIPT_URL instead, which mod_rewrite
3677                 # provides containing the "before" URL.
3678                 return $_SERVER['SCRIPT_NAME'];
3679         } else {
3680                 return $_SERVER['URL'];
3681         }
3682 }
3683
3684 /**
3685  * Convenience function converts boolean values into "true"
3686  * or "false" (string) values
3687  *
3688  * @param bool $value
3689  * @return string
3690  */
3691 function wfBoolToStr( $value ) {
3692         return $value ? 'true' : 'false';
3693 }
3694
3695 /**
3696  * Get a platform-independent path to the null file, e.g. /dev/null
3697  *
3698  * @return string
3699  */
3700 function wfGetNull() {
3701         return wfIsWindows() ? 'NUL' : '/dev/null';
3702 }
3703
3704 /**
3705  * Waits for the slaves to catch up to the master position
3706  *
3707  * Use this when updating very large numbers of rows, as in maintenance scripts,
3708  * to avoid causing too much lag. Of course, this is a no-op if there are no slaves.
3709  *
3710  * By default this waits on the main DB cluster of the current wiki.
3711  * If $cluster is set to "*" it will wait on all DB clusters, including
3712  * external ones. If the lag being waiting on is caused by the code that
3713  * does this check, it makes since to use $ifWritesSince, particularly if
3714  * cluster is "*", to avoid excess overhead.
3715  *
3716  * Never call this function after a big DB write that is still in a transaction.
3717  * This only makes sense after the possible lag inducing changes were committed.
3718  *
3719  * @param float|null $ifWritesSince Only wait if writes were done since this UNIX timestamp
3720  * @param string|bool $wiki Wiki identifier accepted by wfGetLB
3721  * @param string|bool $cluster Cluster name accepted by LBFactory. Default: false.
3722  * @param int|null $timeout Max wait time. Default: 1 day (cli), ~10 seconds (web)
3723  * @return bool Success (able to connect and no timeouts reached)
3724  */
3725 function wfWaitForSlaves(
3726         $ifWritesSince = null, $wiki = false, $cluster = false, $timeout = null
3727 ) {
3728         // B/C: first argument used to be "max seconds of lag"; ignore such values
3729         $ifWritesSince = ( $ifWritesSince > 1e9 ) ? $ifWritesSince : null;
3730
3731         if ( $timeout === null ) {
3732                 $timeout = ( PHP_SAPI === 'cli' ) ? 86400 : 10;
3733         }
3734
3735         // Figure out which clusters need to be checked
3736         /** @var LoadBalancer[] $lbs */
3737         $lbs = array();
3738         if ( $cluster === '*' ) {
3739                 wfGetLBFactory()->forEachLB( function ( LoadBalancer $lb ) use ( &$lbs ) {
3740                         $lbs[] = $lb;
3741                 } );
3742         } elseif ( $cluster !== false ) {
3743                 $lbs[] = wfGetLBFactory()->getExternalLB( $cluster );
3744         } else {
3745                 $lbs[] = wfGetLB( $wiki );
3746         }
3747
3748         // Get all the master positions of applicable DBs right now.
3749         // This can be faster since waiting on one cluster reduces the
3750         // time needed to wait on the next clusters.
3751         $masterPositions = array_fill( 0, count( $lbs ), false );
3752         foreach ( $lbs as $i => $lb ) {
3753                 if ( $lb->getServerCount() <= 1 ) {
3754                         // Bug 27975 - Don't try to wait for slaves if there are none
3755                         // Prevents permission error when getting master position
3756                         continue;
3757                 } elseif ( $ifWritesSince && $lb->lastMasterChangeTimestamp() < $ifWritesSince ) {
3758                         continue; // no writes since the last wait
3759                 }
3760                 $masterPositions[$i] = $lb->getMasterPos();
3761         }
3762
3763         $ok = true;
3764         foreach ( $lbs as $i => $lb ) {
3765                 if ( $masterPositions[$i] ) {
3766                         // The DBMS may not support getMasterPos() or the whole
3767                         // load balancer might be fake (e.g. $wgAllDBsAreLocalhost).
3768                         $ok = $lb->waitForAll( $masterPositions[$i], $timeout ) && $ok;
3769                 }
3770         }
3771
3772         return $ok;
3773 }
3774
3775 /**
3776  * Count down from $seconds to zero on the terminal, with a one-second pause
3777  * between showing each number. For use in command-line scripts.
3778  *
3779  * @codeCoverageIgnore
3780  * @param int $seconds
3781  */
3782 function wfCountDown( $seconds ) {
3783         for ( $i = $seconds; $i >= 0; $i-- ) {
3784                 if ( $i != $seconds ) {
3785                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3786                 }
3787                 echo $i;
3788                 flush();
3789                 if ( $i ) {
3790                         sleep( 1 );
3791                 }
3792         }
3793         echo "\n";
3794 }
3795
3796 /**
3797  * Replace all invalid characters with -
3798  * Additional characters can be defined in $wgIllegalFileChars (see bug 20489)
3799  * By default, $wgIllegalFileChars = ':'
3800  *
3801  * @param string $name Filename to process
3802  * @return string
3803  */
3804 function wfStripIllegalFilenameChars( $name ) {
3805         global $wgIllegalFileChars;
3806         $illegalFileChars = $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '';
3807         $name = wfBaseName( $name );
3808         $name = preg_replace(
3809                 "/[^" . Title::legalChars() . "]" . $illegalFileChars . "/",
3810                 '-',
3811                 $name
3812         );
3813         return $name;
3814 }
3815
3816 /**
3817  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit;
3818  *
3819  * @return int Value the memory limit was set to.
3820  */
3821 function wfMemoryLimit() {
3822         global $wgMemoryLimit;
3823         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3824         if ( $memlimit != -1 ) {
3825                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3826                 if ( $conflimit == -1 ) {
3827                         wfDebug( "Removing PHP's memory limit\n" );
3828                         MediaWiki\suppressWarnings();
3829                         ini_set( 'memory_limit', $conflimit );
3830                         MediaWiki\restoreWarnings();
3831                         return $conflimit;
3832                 } elseif ( $conflimit > $memlimit ) {
3833                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3834                         MediaWiki\suppressWarnings();
3835                         ini_set( 'memory_limit', $conflimit );
3836                         MediaWiki\restoreWarnings();
3837                         return $conflimit;
3838                 }
3839         }
3840         return $memlimit;
3841 }
3842
3843 /**
3844  * Converts shorthand byte notation to integer form
3845  *
3846  * @param string $string
3847  * @return int
3848  */
3849 function wfShorthandToInteger( $string = '' ) {
3850         $string = trim( $string );
3851         if ( $string === '' ) {
3852                 return -1;
3853         }
3854         $last = $string[strlen( $string ) - 1];
3855         $val = intval( $string );
3856         switch ( $last ) {
3857                 case 'g':
3858                 case 'G':
3859                         $val *= 1024;
3860                         // break intentionally missing
3861                 case 'm':
3862                 case 'M':
3863                         $val *= 1024;
3864                         // break intentionally missing
3865                 case 'k':
3866                 case 'K':
3867                         $val *= 1024;
3868         }
3869
3870         return $val;
3871 }
3872
3873 /**
3874  * Get the normalised IETF language tag
3875  * See unit test for examples.
3876  *
3877  * @param string $code The language code.
3878  * @return string The language code which complying with BCP 47 standards.
3879  */
3880 function wfBCP47( $code ) {
3881         $codeSegment = explode( '-', $code );
3882         $codeBCP = array();
3883         foreach ( $codeSegment as $segNo => $seg ) {
3884                 // when previous segment is x, it is a private segment and should be lc
3885                 if ( $segNo > 0 && strtolower( $codeSegment[( $segNo - 1 )] ) == 'x' ) {
3886                         $codeBCP[$segNo] = strtolower( $seg );
3887                 // ISO 3166 country code
3888                 } elseif ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3889                         $codeBCP[$segNo] = strtoupper( $seg );
3890                 // ISO 15924 script code
3891                 } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3892                         $codeBCP[$segNo] = ucfirst( strtolower( $seg ) );
3893                 // Use lowercase for other cases
3894                 } else {
3895                         $codeBCP[$segNo] = strtolower( $seg );
3896                 }
3897         }
3898         $langCode = implode( '-', $codeBCP );
3899         return $langCode;
3900 }
3901
3902 /**
3903  * Get a cache object.
3904  *
3905  * @param int $inputType Cache type, one of the CACHE_* constants.
3906  * @return BagOStuff
3907  */
3908 function wfGetCache( $inputType ) {
3909         return ObjectCache::getInstance( $inputType );
3910 }
3911
3912 /**
3913  * Get the main cache object
3914  *
3915  * @return BagOStuff
3916  */
3917 function wfGetMainCache() {
3918         global $wgMainCacheType;
3919         return ObjectCache::getInstance( $wgMainCacheType );
3920 }
3921
3922 /**
3923  * Get the cache object used by the message cache
3924  *
3925  * @return BagOStuff
3926  */
3927 function wfGetMessageCacheStorage() {
3928         global $wgMessageCacheType;
3929         return ObjectCache::getInstance( $wgMessageCacheType );
3930 }
3931
3932 /**
3933  * Get the cache object used by the parser cache
3934  *
3935  * @return BagOStuff
3936  */
3937 function wfGetParserCacheStorage() {
3938         global $wgParserCacheType;
3939         return ObjectCache::getInstance( $wgParserCacheType );
3940 }
3941
3942 /**
3943  * Call hook functions defined in $wgHooks
3944  *
3945  * @param string $event Event name
3946  * @param array $args Parameters passed to hook functions
3947  * @param string|null $deprecatedVersion Optionally mark hook as deprecated with version number
3948  *
3949  * @return bool True if no handler aborted the hook
3950  * @deprecated 1.25 - use Hooks::run
3951  */
3952 function wfRunHooks( $event, array $args = array(), $deprecatedVersion = null ) {
3953         return Hooks::run( $event, $args, $deprecatedVersion );
3954 }
3955
3956 /**
3957  * Wrapper around php's unpack.
3958  *
3959  * @param string $format The format string (See php's docs)
3960  * @param string $data A binary string of binary data
3961  * @param int|bool $length The minimum length of $data or false. This is to
3962  *      prevent reading beyond the end of $data. false to disable the check.
3963  *
3964  * Also be careful when using this function to read unsigned 32 bit integer
3965  * because php might make it negative.
3966  *
3967  * @throws MWException If $data not long enough, or if unpack fails
3968  * @return array Associative array of the extracted data
3969  */
3970 function wfUnpack( $format, $data, $length = false ) {
3971         if ( $length !== false ) {
3972                 $realLen = strlen( $data );
3973                 if ( $realLen < $length ) {
3974                         throw new MWException( "Tried to use wfUnpack on a "
3975                                 . "string of length $realLen, but needed one "
3976                                 . "of at least length $length."
3977                         );
3978                 }
3979         }
3980
3981         MediaWiki\suppressWarnings();
3982         $result = unpack( $format, $data );
3983         MediaWiki\restoreWarnings();
3984
3985         if ( $result === false ) {
3986                 // If it cannot extract the packed data.
3987                 throw new MWException( "unpack could not unpack binary data" );
3988         }
3989         return $result;
3990 }
3991
3992 /**
3993  * Determine if an image exists on the 'bad image list'.
3994  *
3995  * The format of MediaWiki:Bad_image_list is as follows:
3996  *    * Only list items (lines starting with "*") are considered
3997  *    * The first link on a line must be a link to a bad image
3998  *    * Any subsequent links on the same line are considered to be exceptions,
3999  *      i.e. articles where the image may occur inline.
4000  *
4001  * @param string $name The image name to check
4002  * @param Title|bool $contextTitle The page on which the image occurs, if known
4003  * @param string $blacklist Wikitext of a file blacklist
4004  * @return bool
4005  */
4006 function wfIsBadImage( $name, $contextTitle = false, $blacklist = null ) {
4007         static $badImageCache = null; // based on bad_image_list msg
4008
4009         # Handle redirects
4010         $redirectTitle = RepoGroup::singleton()->checkRedirect( Title::makeTitle( NS_FILE, $name ) );
4011         if ( $redirectTitle ) {
4012                 $name = $redirectTitle->getDBkey();
4013         }
4014
4015         # Run the extension hook
4016         $bad = false;
4017         if ( !Hooks::run( 'BadImage', array( $name, &$bad ) ) ) {
4018                 return $bad;
4019         }
4020
4021         $cacheable = ( $blacklist === null );
4022         if ( $cacheable && $badImageCache !== null ) {
4023                 $badImages = $badImageCache;
4024         } else { // cache miss
4025                 if ( $blacklist === null ) {
4026                         $blacklist = wfMessage( 'bad_image_list' )->inContentLanguage()->plain(); // site list
4027                 }
4028                 # Build the list now
4029                 $badImages = array();
4030                 $lines = explode( "\n", $blacklist );
4031                 foreach ( $lines as $line ) {
4032                         # List items only
4033                         if ( substr( $line, 0, 1 ) !== '*' ) {
4034                                 continue;
4035                         }
4036
4037                         # Find all links
4038                         $m = array();
4039                         if ( !preg_match_all( '/\[\[:?(.*?)\]\]/', $line, $m ) ) {
4040                                 continue;
4041                         }
4042
4043                         $exceptions = array();
4044                         $imageDBkey = false;
4045                         foreach ( $m[1] as $i => $titleText ) {
4046                                 $title = Title::newFromText( $titleText );
4047                                 if ( !is_null( $title ) ) {
4048                                         if ( $i == 0 ) {
4049                                                 $imageDBkey = $title->getDBkey();
4050                                         } else {
4051                                                 $exceptions[$title->getPrefixedDBkey()] = true;
4052                                         }
4053                                 }
4054                         }
4055
4056                         if ( $imageDBkey !== false ) {
4057                                 $badImages[$imageDBkey] = $exceptions;
4058                         }
4059                 }
4060                 if ( $cacheable ) {
4061                         $badImageCache = $badImages;
4062                 }
4063         }
4064
4065         $contextKey = $contextTitle ? $contextTitle->getPrefixedDBkey() : false;
4066         $bad = isset( $badImages[$name] ) && !isset( $badImages[$name][$contextKey] );
4067         return $bad;
4068 }
4069
4070 /**
4071  * Determine whether the client at a given source IP is likely to be able to
4072  * access the wiki via HTTPS.
4073  *
4074  * @param string $ip The IPv4/6 address in the normal human-readable form
4075  * @return bool
4076  */
4077 function wfCanIPUseHTTPS( $ip ) {
4078         $canDo = true;
4079         Hooks::run( 'CanIPUseHTTPS', array( $ip, &$canDo ) );
4080         return !!$canDo;
4081 }
4082
4083 /**
4084  * Determine input string is represents as infinity
4085  *
4086  * @param string $str The string to determine
4087  * @return bool
4088  * @since 1.25
4089  */
4090 function wfIsInfinity( $str ) {
4091         $infinityValues = array( 'infinite', 'indefinite', 'infinity', 'never' );
4092         return in_array( $str, $infinityValues );
4093 }
4094
4095 /**
4096  * Work out the IP address based on various globals
4097  * For trusted proxies, use the XFF client IP (first of the chain)
4098  *
4099  * @deprecated since 1.19; call $wgRequest->getIP() directly.
4100  * @return string
4101  */
4102 function wfGetIP() {
4103         wfDeprecated( __METHOD__, '1.19' );
4104         global $wgRequest;
4105         return $wgRequest->getIP();
4106 }
4107
4108 /**
4109  * Checks if an IP is a trusted proxy provider.
4110  * Useful to tell if X-Forwarded-For data is possibly bogus.
4111  * Squid cache servers for the site are whitelisted.
4112  * @deprecated Since 1.24, use IP::isTrustedProxy()
4113  *
4114  * @param string $ip
4115  * @return bool
4116  */
4117 function wfIsTrustedProxy( $ip ) {
4118         wfDeprecated( __METHOD__, '1.24' );
4119         return IP::isTrustedProxy( $ip );
4120 }
4121
4122 /**
4123  * Checks if an IP matches a proxy we've configured.
4124  * @deprecated Since 1.24, use IP::isConfiguredProxy()
4125  *
4126  * @param string $ip
4127  * @return bool
4128  * @since 1.23 Supports CIDR ranges in $wgSquidServersNoPurge
4129  */
4130 function wfIsConfiguredProxy( $ip ) {
4131         wfDeprecated( __METHOD__, '1.24' );
4132         return IP::isConfiguredProxy( $ip );
4133 }
4134
4135 /**
4136  * Returns true if these thumbnail parameters match one that MediaWiki
4137  * requests from file description pages and/or parser output.
4138  *
4139  * $params is considered non-standard if they involve a non-standard
4140  * width or any non-default parameters aside from width and page number.
4141  * The number of possible files with standard parameters is far less than
4142  * that of all combinations; rate-limiting for them can thus be more generious.
4143  *
4144  * @param File $file
4145  * @param array $params
4146  * @return bool
4147  * @since 1.24 Moved from thumb.php to GlobalFunctions in 1.25
4148  */
4149 function wfThumbIsStandard( File $file, array $params ) {
4150         global $wgThumbLimits, $wgImageLimits, $wgResponsiveImages;
4151
4152         $multipliers = array( 1 );
4153         if ( $wgResponsiveImages ) {
4154                 // These available sizes are hardcoded currently elsewhere in MediaWiki.
4155                 // @see Linker::processResponsiveImages
4156                 $multipliers[] = 1.5;
4157                 $multipliers[] = 2;
4158         }
4159
4160         $handler = $file->getHandler();
4161         if ( !$handler || !isset( $params['width'] ) ) {
4162                 return false;
4163         }
4164
4165         $basicParams = array();
4166         if ( isset( $params['page'] ) ) {
4167                 $basicParams['page'] = $params['page'];
4168         }
4169
4170         $thumbLimits = array();
4171         $imageLimits = array();
4172         // Expand limits to account for multipliers
4173         foreach ( $multipliers as $multiplier ) {
4174                 $thumbLimits = array_merge( $thumbLimits, array_map(
4175                         function ( $width ) use ( $multiplier ) {
4176                                 return round( $width * $multiplier );
4177                         }, $wgThumbLimits )
4178                 );
4179                 $imageLimits = array_merge( $imageLimits, array_map(
4180                         function ( $pair ) use ( $multiplier ) {
4181                                 return array(
4182                                         round( $pair[0] * $multiplier ),
4183                                         round( $pair[1] * $multiplier ),
4184                                 );
4185                         }, $wgImageLimits )
4186                 );
4187         }
4188
4189         // Check if the width matches one of $wgThumbLimits
4190         if ( in_array( $params['width'], $thumbLimits ) ) {
4191                 $normalParams = $basicParams + array( 'width' => $params['width'] );
4192                 // Append any default values to the map (e.g. "lossy", "lossless", ...)
4193                 $handler->normaliseParams( $file, $normalParams );
4194         } else {
4195                 // If not, then check if the width matchs one of $wgImageLimits
4196                 $match = false;
4197                 foreach ( $imageLimits as $pair ) {
4198                         $normalParams = $basicParams + array( 'width' => $pair[0], 'height' => $pair[1] );
4199                         // Decide whether the thumbnail should be scaled on width or height.
4200                         // Also append any default values to the map (e.g. "lossy", "lossless", ...)
4201                         $handler->normaliseParams( $file, $normalParams );
4202                         // Check if this standard thumbnail size maps to the given width
4203                         if ( $normalParams['width'] == $params['width'] ) {
4204                                 $match = true;
4205                                 break;
4206                         }
4207                 }
4208                 if ( !$match ) {
4209                         return false; // not standard for description pages
4210                 }
4211         }
4212
4213         // Check that the given values for non-page, non-width, params are just defaults
4214         foreach ( $params as $key => $value ) {
4215                 if ( !isset( $normalParams[$key] ) || $normalParams[$key] != $value ) {
4216                         return false;
4217                 }
4218         }
4219
4220         return true;
4221 }