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\Sender\SocketSender;
  28 use MediaWiki\Logger\LoggerFactory;
  29 use MediaWiki\Session\SessionManager;
  30 use MediaWiki\MediaWikiServices;
  31 use Wikimedia\ScopedCallback;
  32 use Wikimedia\Rdbms\DBReplicationWaitError;
  33
  34 // Hide compatibility functions from Doxygen
  35 /// @cond
  36 /**
  37  * Compatibility functions
  38  *
  39  * We support PHP 5.5.9 and up.
  40  * Re-implementations of newer functions or functions in non-standard
  41  * PHP extensions may be included here.
  42  */
  43
  44 // hash_equals function only exists in PHP >= 5.6.0
  45 // https://secure.php.net/hash_equals
  46 if ( !function_exists( 'hash_equals' ) ) {
  47         /**
  48          * Check whether a user-provided string is equal to a fixed-length secret string
  49          * without revealing bytes of the secret string through timing differences.
  50          *
  51          * The usual way to compare strings (PHP's === operator or the underlying memcmp()
  52          * function in C) is to compare corresponding bytes and stop at the first difference,
  53          * which would take longer for a partial match than for a complete mismatch. This
  54          * is not secure when one of the strings (e.g. an HMAC or token) must remain secret
  55          * and the other may come from an attacker. Statistical analysis of timing measurements
  56          * over many requests may allow the attacker to guess the string's bytes one at a time
  57          * (and check his guesses) even if the timing differences are extremely small.
  58          *
  59          * When making such a security-sensitive comparison, it is essential that the sequence
  60          * in which instructions are executed and memory locations are accessed not depend on
  61          * the secret string's value. HOWEVER, for simplicity, we do not attempt to minimize
  62          * the inevitable leakage of the string's length. That is generally known anyway as
  63          * a chararacteristic of the hash function used to compute the secret value.
  64          *
  65          * Longer explanation: http://www.emerose.com/timing-attacks-explained
  66          *
  67          * @codeCoverageIgnore
  68          * @param string $known_string Fixed-length secret string to compare against
  69          * @param string $user_string User-provided string
  70          * @return bool True if the strings are the same, false otherwise
  71          */
  72         function hash_equals( $known_string, $user_string ) {
  73                 // Strict type checking as in PHP's native implementation
  74                 if ( !is_string( $known_string ) ) {
  75                         trigger_error( 'hash_equals(): Expected known_string to be a string, ' .
  76                                 gettype( $known_string ) . ' given', E_USER_WARNING );
  77
  78                         return false;
  79                 }
  80
  81                 if ( !is_string( $user_string ) ) {
  82                         trigger_error( 'hash_equals(): Expected user_string to be a string, ' .
  83                                 gettype( $user_string ) . ' given', E_USER_WARNING );
  84
  85                         return false;
  86                 }
  87
  88                 $known_string_len = strlen( $known_string );
  89                 if ( $known_string_len !== strlen( $user_string ) ) {
  90                         return false;
  91                 }
  92
  93                 $result = 0;
  94                 for ( $i = 0; $i < $known_string_len; $i++ ) {
  95                         $result |= ord( $known_string[$i] ) ^ ord( $user_string[$i] );
  96                 }
  97
  98                 return ( $result === 0 );
  99         }
 100 }
 101 /// @endcond
 102
 103 /**
 104  * Load an extension
 105  *
 106  * This queues an extension to be loaded through
 107  * the ExtensionRegistry system.
 108  *
 109  * @param string $ext Name of the extension to load
 110  * @param string|null $path Absolute path of where to find the extension.json file
 111  * @since 1.25
 112  */
 113 function wfLoadExtension( $ext, $path = null ) {
 114         if ( !$path ) {
 115                 global $wgExtensionDirectory;
 116                 $path = "$wgExtensionDirectory/$ext/extension.json";
 117         }
 118         ExtensionRegistry::getInstance()->queue( $path );
 119 }
 120
 121 /**
 122  * Load multiple extensions at once
 123  *
 124  * Same as wfLoadExtension, but more efficient if you
 125  * are loading multiple extensions.
 126  *
 127  * If you want to specify custom paths, you should interact with
 128  * ExtensionRegistry directly.
 129  *
 130  * @see wfLoadExtension
 131  * @param string[] $exts Array of extension names to load
 132  * @since 1.25
 133  */
 134 function wfLoadExtensions( array $exts ) {
 135         global $wgExtensionDirectory;
 136         $registry = ExtensionRegistry::getInstance();
 137         foreach ( $exts as $ext ) {
 138                 $registry->queue( "$wgExtensionDirectory/$ext/extension.json" );
 139         }
 140 }
 141
 142 /**
 143  * Load a skin
 144  *
 145  * @see wfLoadExtension
 146  * @param string $skin Name of the extension to load
 147  * @param string|null $path Absolute path of where to find the skin.json file
 148  * @since 1.25
 149  */
 150 function wfLoadSkin( $skin, $path = null ) {
 151         if ( !$path ) {
 152                 global $wgStyleDirectory;
 153                 $path = "$wgStyleDirectory/$skin/skin.json";
 154         }
 155         ExtensionRegistry::getInstance()->queue( $path );
 156 }
 157
 158 /**
 159  * Load multiple skins at once
 160  *
 161  * @see wfLoadExtensions
 162  * @param string[] $skins Array of extension names to load
 163  * @since 1.25
 164  */
 165 function wfLoadSkins( array $skins ) {
 166         global $wgStyleDirectory;
 167         $registry = ExtensionRegistry::getInstance();
 168         foreach ( $skins as $skin ) {
 169                 $registry->queue( "$wgStyleDirectory/$skin/skin.json" );
 170         }
 171 }
 172
 173 /**
 174  * Like array_diff( $a, $b ) except that it works with two-dimensional arrays.
 175  * @param array $a
 176  * @param array $b
 177  * @return array
 178  */
 179 function wfArrayDiff2( $a, $b ) {
 180         return array_udiff( $a, $b, 'wfArrayDiff2_cmp' );
 181 }
 182
 183 /**
 184  * @param array|string $a
 185  * @param array|string $b
 186  * @return int
 187  */
 188 function wfArrayDiff2_cmp( $a, $b ) {
 189         if ( is_string( $a ) && is_string( $b ) ) {
 190                 return strcmp( $a, $b );
 191         } elseif ( count( $a ) !== count( $b ) ) {
 192                 return count( $a ) < count( $b ) ? -1 : 1;
 193         } else {
 194                 reset( $a );
 195                 reset( $b );
 196                 while ( ( list( , $valueA ) = each( $a ) ) && ( list( , $valueB ) = each( $b ) ) ) {
 197                         $cmp = strcmp( $valueA, $valueB );
 198                         if ( $cmp !== 0 ) {
 199                                 return $cmp;
 200                         }
 201                 }
 202                 return 0;
 203         }
 204 }
 205
 206 /**
 207  * Like array_filter with ARRAY_FILTER_USE_BOTH, but works pre-5.6.
 208  *
 209  * @param array $arr
 210  * @param callable $callback Will be called with the array value and key (in that order) and
 211  *   should return a bool which will determine whether the array element is kept.
 212  * @return array
 213  */
 214 function wfArrayFilter( array $arr, callable $callback ) {
 215         if ( defined( 'ARRAY_FILTER_USE_BOTH' ) ) {
 216                 return array_filter( $arr, $callback, ARRAY_FILTER_USE_BOTH );
 217         }
 218         $filteredKeys = array_filter( array_keys( $arr ), function ( $key ) use ( $arr, $callback ) {
 219                 return call_user_func( $callback, $arr[$key], $key );
 220         } );
 221         return array_intersect_key( $arr, array_fill_keys( $filteredKeys, true ) );
 222 }
 223
 224 /**
 225  * Like array_filter with ARRAY_FILTER_USE_KEY, but works pre-5.6.
 226  *
 227  * @param array $arr
 228  * @param callable $callback Will be called with the array key and should return a bool which
 229  *   will determine whether the array element is kept.
 230  * @return array
 231  */
 232 function wfArrayFilterByKey( array $arr, callable $callback ) {
 233         return wfArrayFilter( $arr, function ( $val, $key ) use ( $callback ) {
 234                 return call_user_func( $callback, $key );
 235         } );
 236 }
 237
 238 /**
 239  * Appends to second array if $value differs from that in $default
 240  *
 241  * @param string|int $key
 242  * @param mixed $value
 243  * @param mixed $default
 244  * @param array $changed Array to alter
 245  * @throws MWException
 246  */
 247 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
 248         if ( is_null( $changed ) ) {
 249                 throw new MWException( 'GlobalFunctions::wfAppendToArrayIfNotDefault got null' );
 250         }
 251         if ( $default[$key] !== $value ) {
 252                 $changed[$key] = $value;
 253         }
 254 }
 255
 256 /**
 257  * Merge arrays in the style of getUserPermissionsErrors, with duplicate removal
 258  * e.g.
 259  *     wfMergeErrorArrays(
 260  *       [ [ 'x' ] ],
 261  *       [ [ 'x', '2' ] ],
 262  *       [ [ 'x' ] ],
 263  *       [ [ 'y' ] ]
 264  *     );
 265  * returns:
 266  *     [
 267  *       [ 'x', '2' ],
 268  *       [ 'x' ],
 269  *       [ 'y' ]
 270  *     ]
 271  *
 272  * @param array $array1,...
 273  * @return array
 274  */
 275 function wfMergeErrorArrays( /*...*/ ) {
 276         $args = func_get_args();
 277         $out = [];
 278         foreach ( $args as $errors ) {
 279                 foreach ( $errors as $params ) {
 280                         $originalParams = $params;
 281                         if ( $params[0] instanceof MessageSpecifier ) {
 282                                 $msg = $params[0];
 283                                 $params = array_merge( [ $msg->getKey() ], $msg->getParams() );
 284                         }
 285                         # @todo FIXME: Sometimes get nested arrays for $params,
 286                         # which leads to E_NOTICEs
 287                         $spec = implode( "\t", $params );
 288                         $out[$spec] = $originalParams;
 289                 }
 290         }
 291         return array_values( $out );
 292 }
 293
 294 /**
 295  * Insert array into another array after the specified *KEY*
 296  *
 297  * @param array $array The array.
 298  * @param array $insert The array to insert.
 299  * @param mixed $after The key to insert after
 300  * @return array
 301  */
 302 function wfArrayInsertAfter( array $array, array $insert, $after ) {
 303         // Find the offset of the element to insert after.
 304         $keys = array_keys( $array );
 305         $offsetByKey = array_flip( $keys );
 306
 307         $offset = $offsetByKey[$after];
 308
 309         // Insert at the specified offset
 310         $before = array_slice( $array, 0, $offset + 1, true );
 311         $after = array_slice( $array, $offset + 1, count( $array ) - $offset, true );
 312
 313         $output = $before + $insert + $after;
 314
 315         return $output;
 316 }
 317
 318 /**
 319  * Recursively converts the parameter (an object) to an array with the same data
 320  *
 321  * @param object|array $objOrArray
 322  * @param bool $recursive
 323  * @return array
 324  */
 325 function wfObjectToArray( $objOrArray, $recursive = true ) {
 326         $array = [];
 327         if ( is_object( $objOrArray ) ) {
 328                 $objOrArray = get_object_vars( $objOrArray );
 329         }
 330         foreach ( $objOrArray as $key => $value ) {
 331                 if ( $recursive && ( is_object( $value ) || is_array( $value ) ) ) {
 332                         $value = wfObjectToArray( $value );
 333                 }
 334
 335                 $array[$key] = $value;
 336         }
 337
 338         return $array;
 339 }
 340
 341 /**
 342  * Get a random decimal value between 0 and 1, in a way
 343  * not likely to give duplicate values for any realistic
 344  * number of articles.
 345  *
 346  * @note This is designed for use in relation to Special:RandomPage
 347  *       and the page_random database field.
 348  *
 349  * @return string
 350  */
 351 function wfRandom() {
 352         // The maximum random value is "only" 2^31-1, so get two random
 353         // values to reduce the chance of dupes
 354         $max = mt_getrandmax() + 1;
 355         $rand = number_format( ( mt_rand() * $max + mt_rand() ) / $max / $max, 12, '.', '' );
 356         return $rand;
 357 }
 358
 359 /**
 360  * Get a random string containing a number of pseudo-random hex characters.
 361  *
 362  * @note This is not secure, if you are trying to generate some sort
 363  *       of token please use MWCryptRand instead.
 364  *
 365  * @param int $length The length of the string to generate
 366  * @return string
 367  * @since 1.20
 368  */
 369 function wfRandomString( $length = 32 ) {
 370         $str = '';
 371         for ( $n = 0; $n < $length; $n += 7 ) {
 372                 $str .= sprintf( '%07x', mt_rand() & 0xfffffff );
 373         }
 374         return substr( $str, 0, $length );
 375 }
 376
 377 /**
 378  * We want some things to be included as literal characters in our title URLs
 379  * for prettiness, which urlencode encodes by default.  According to RFC 1738,
 380  * all of the following should be safe:
 381  *
 382  * ;:@&=$-_.+!*'(),
 383  *
 384  * RFC 1738 says ~ is unsafe, however RFC 3986 considers it an unreserved
 385  * character which should not be encoded. More importantly, google chrome
 386  * always converts %7E back to ~, and converting it in this function can
 387  * cause a redirect loop (T105265).
 388  *
 389  * But + is not safe because it's used to indicate a space; &= are only safe in
 390  * paths and not in queries (and we don't distinguish here); ' seems kind of
 391  * scary; and urlencode() doesn't touch -_. to begin with.  Plus, although /
 392  * is reserved, we don't care.  So the list we unescape is:
 393  *
 394  * ;:@$!*(),/~
 395  *
 396  * However, IIS7 redirects fail when the url contains a colon (see T24709),
 397  * so no fancy : for IIS7.
 398  *
 399  * %2F in the page titles seems to fatally break for some reason.
 400  *
 401  * @param string $s
 402  * @return string
 403  */
 404 function wfUrlencode( $s ) {
 405         static $needle;
 406
 407         if ( is_null( $s ) ) {
 408                 $needle = null;
 409                 return '';
 410         }
 411
 412         if ( is_null( $needle ) ) {
 413                 $needle = [ '%3B', '%40', '%24', '%21', '%2A', '%28', '%29', '%2C', '%2F', '%7E' ];
 414                 if ( !isset( $_SERVER['SERVER_SOFTWARE'] ) ||
 415                         ( strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/7' ) === false )
 416                 ) {
 417                         $needle[] = '%3A';
 418                 }
 419         }
 420
 421         $s = urlencode( $s );
 422         $s = str_ireplace(
 423                 $needle,
 424                 [ ';', '@', '$', '!', '*', '(', ')', ',', '/', '~', ':' ],
 425                 $s
 426         );
 427
 428         return $s;
 429 }
 430
 431 /**
 432  * This function takes one or two arrays as input, and returns a CGI-style string, e.g.
 433  * "days=7&limit=100". Options in the first array override options in the second.
 434  * Options set to null or false will not be output.
 435  *
 436  * @param array $array1 ( String|Array )
 437  * @param array|null $array2 ( String|Array )
 438  * @param string $prefix
 439  * @return string
 440  */
 441 function wfArrayToCgi( $array1, $array2 = null, $prefix = '' ) {
 442         if ( !is_null( $array2 ) ) {
 443                 $array1 = $array1 + $array2;
 444         }
 445
 446         $cgi = '';
 447         foreach ( $array1 as $key => $value ) {
 448                 if ( !is_null( $value ) && $value !== false ) {
 449                         if ( $cgi != '' ) {
 450                                 $cgi .= '&';
 451                         }
 452                         if ( $prefix !== '' ) {
 453                                 $key = $prefix . "[$key]";
 454                         }
 455                         if ( is_array( $value ) ) {
 456                                 $firstTime = true;
 457                                 foreach ( $value as $k => $v ) {
 458                                         $cgi .= $firstTime ? '' : '&';
 459                                         if ( is_array( $v ) ) {
 460                                                 $cgi .= wfArrayToCgi( $v, null, $key . "[$k]" );
 461                                         } else {
 462                                                 $cgi .= urlencode( $key . "[$k]" ) . '=' . urlencode( $v );
 463                                         }
 464                                         $firstTime = false;
 465                                 }
 466                         } else {
 467                                 if ( is_object( $value ) ) {
 468                                         $value = $value->__toString();
 469                                 }
 470                                 $cgi .= urlencode( $key ) . '=' . urlencode( $value );
 471                         }
 472                 }
 473         }
 474         return $cgi;
 475 }
 476
 477 /**
 478  * This is the logical opposite of wfArrayToCgi(): it accepts a query string as
 479  * its argument and returns the same string in array form.  This allows compatibility
 480  * with legacy functions that accept raw query strings instead of nice
 481  * arrays.  Of course, keys and values are urldecode()d.
 482  *
 483  * @param string $query Query string
 484  * @return string[] Array version of input
 485  */
 486 function wfCgiToArray( $query ) {
 487         if ( isset( $query[0] ) && $query[0] == '?' ) {
 488                 $query = substr( $query, 1 );
 489         }
 490         $bits = explode( '&', $query );
 491         $ret = [];
 492         foreach ( $bits as $bit ) {
 493                 if ( $bit === '' ) {
 494                         continue;
 495                 }
 496                 if ( strpos( $bit, '=' ) === false ) {
 497                         // Pieces like &qwerty become 'qwerty' => '' (at least this is what php does)
 498                         $key = $bit;
 499                         $value = '';
 500                 } else {
 501                         list( $key, $value ) = explode( '=', $bit );
 502                 }
 503                 $key = urldecode( $key );
 504                 $value = urldecode( $value );
 505                 if ( strpos( $key, '[' ) !== false ) {
 506                         $keys = array_reverse( explode( '[', $key ) );
 507                         $key = array_pop( $keys );
 508                         $temp = $value;
 509                         foreach ( $keys as $k ) {
 510                                 $k = substr( $k, 0, -1 );
 511                                 $temp = [ $k => $temp ];
 512                         }
 513                         if ( isset( $ret[$key] ) ) {
 514                                 $ret[$key] = array_merge( $ret[$key], $temp );
 515                         } else {
 516                                 $ret[$key] = $temp;
 517                         }
 518                 } else {
 519                         $ret[$key] = $value;
 520                 }
 521         }
 522         return $ret;
 523 }
 524
 525 /**
 526  * Append a query string to an existing URL, which may or may not already
 527  * have query string parameters already. If so, they will be combined.
 528  *
 529  * @param string $url
 530  * @param string|string[] $query String or associative array
 531  * @return string
 532  */
 533 function wfAppendQuery( $url, $query ) {
 534         if ( is_array( $query ) ) {
 535                 $query = wfArrayToCgi( $query );
 536         }
 537         if ( $query != '' ) {
 538                 // Remove the fragment, if there is one
 539                 $fragment = false;
 540                 $hashPos = strpos( $url, '#' );
 541                 if ( $hashPos !== false ) {
 542                         $fragment = substr( $url, $hashPos );
 543                         $url = substr( $url, 0, $hashPos );
 544                 }
 545
 546                 // Add parameter
 547                 if ( false === strpos( $url, '?' ) ) {
 548                         $url .= '?';
 549                 } else {
 550                         $url .= '&';
 551                 }
 552                 $url .= $query;
 553
 554                 // Put the fragment back
 555                 if ( $fragment !== false ) {
 556                         $url .= $fragment;
 557                 }
 558         }
 559         return $url;
 560 }
 561
 562 /**
 563  * Expand a potentially local URL to a fully-qualified URL. Assumes $wgServer
 564  * is correct.
 565  *
 566  * The meaning of the PROTO_* constants is as follows:
 567  * PROTO_HTTP: Output a URL starting with http://
 568  * PROTO_HTTPS: Output a URL starting with https://
 569  * PROTO_RELATIVE: Output a URL starting with // (protocol-relative URL)
 570  * PROTO_CURRENT: Output a URL starting with either http:// or https:// , depending
 571  *    on which protocol was used for the current incoming request
 572  * PROTO_CANONICAL: For URLs without a domain, like /w/index.php , use $wgCanonicalServer.
 573  *    For protocol-relative URLs, use the protocol of $wgCanonicalServer
 574  * PROTO_INTERNAL: Like PROTO_CANONICAL, but uses $wgInternalServer instead of $wgCanonicalServer
 575  *
 576  * @todo this won't work with current-path-relative URLs
 577  * like "subdir/foo.html", etc.
 578  *
 579  * @param string $url Either fully-qualified or a local path + query
 580  * @param string $defaultProto One of the PROTO_* constants. Determines the
 581  *    protocol to use if $url or $wgServer is protocol-relative
 582  * @return string|false Fully-qualified URL, current-path-relative URL or false if
 583  *    no valid URL can be constructed
 584  */
 585 function wfExpandUrl( $url, $defaultProto = PROTO_CURRENT ) {
 586         global $wgServer, $wgCanonicalServer, $wgInternalServer, $wgRequest,
 587                 $wgHttpsPort;
 588         if ( $defaultProto === PROTO_CANONICAL ) {
 589                 $serverUrl = $wgCanonicalServer;
 590         } elseif ( $defaultProto === PROTO_INTERNAL && $wgInternalServer !== false ) {
 591                 // Make $wgInternalServer fall back to $wgServer if not set
 592                 $serverUrl = $wgInternalServer;
 593         } else {
 594                 $serverUrl = $wgServer;
 595                 if ( $defaultProto === PROTO_CURRENT ) {
 596                         $defaultProto = $wgRequest->getProtocol() . '://';
 597                 }
 598         }
 599
 600         // Analyze $serverUrl to obtain its protocol
 601         $bits = wfParseUrl( $serverUrl );
 602         $serverHasProto = $bits && $bits['scheme'] != '';
 603
 604         if ( $defaultProto === PROTO_CANONICAL || $defaultProto === PROTO_INTERNAL ) {
 605                 if ( $serverHasProto ) {
 606                         $defaultProto = $bits['scheme'] . '://';
 607                 } else {
 608                         // $wgCanonicalServer or $wgInternalServer doesn't have a protocol.
 609                         // This really isn't supposed to happen. Fall back to HTTP in this
 610                         // ridiculous case.
 611                         $defaultProto = PROTO_HTTP;
 612                 }
 613         }
 614
 615         $defaultProtoWithoutSlashes = substr( $defaultProto, 0, -2 );
 616
 617         if ( substr( $url, 0, 2 ) == '//' ) {
 618                 $url = $defaultProtoWithoutSlashes . $url;
 619         } elseif ( substr( $url, 0, 1 ) == '/' ) {
 620                 // If $serverUrl is protocol-relative, prepend $defaultProtoWithoutSlashes,
 621                 // otherwise leave it alone.
 622                 $url = ( $serverHasProto ? '' : $defaultProtoWithoutSlashes ) . $serverUrl . $url;
 623         }
 624
 625         $bits = wfParseUrl( $url );
 626
 627         // ensure proper port for HTTPS arrives in URL
 628         // https://phabricator.wikimedia.org/T67184
 629         if ( $defaultProto === PROTO_HTTPS && $wgHttpsPort != 443 ) {
 630                 $bits['port'] = $wgHttpsPort;
 631         }
 632
 633         if ( $bits && isset( $bits['path'] ) ) {
 634                 $bits['path'] = wfRemoveDotSegments( $bits['path'] );
 635                 return wfAssembleUrl( $bits );
 636         } elseif ( $bits ) {
 637                 # No path to expand
 638                 return $url;
 639         } elseif ( substr( $url, 0, 1 ) != '/' ) {
 640                 # URL is a relative path
 641                 return wfRemoveDotSegments( $url );
 642         }
 643
 644         # Expanded URL is not valid.
 645         return false;
 646 }
 647
 648 /**
 649  * This function will reassemble a URL parsed with wfParseURL.  This is useful
 650  * if you need to edit part of a URL and put it back together.
 651  *
 652  * This is the basic structure used (brackets contain keys for $urlParts):
 653  * [scheme][delimiter][user]:[pass]@[host]:[port][path]?[query]#[fragment]
 654  *
 655  * @todo Need to integrate this into wfExpandUrl (see T34168)
 656  *
 657  * @since 1.19
 658  * @param array $urlParts URL parts, as output from wfParseUrl
 659  * @return string URL assembled from its component parts
 660  */
 661 function wfAssembleUrl( $urlParts ) {
 662         $result = '';
 663
 664         if ( isset( $urlParts['delimiter'] ) ) {
 665                 if ( isset( $urlParts['scheme'] ) ) {
 666                         $result .= $urlParts['scheme'];
 667                 }
 668
 669                 $result .= $urlParts['delimiter'];
 670         }
 671
 672         if ( isset( $urlParts['host'] ) ) {
 673                 if ( isset( $urlParts['user'] ) ) {
 674                         $result .= $urlParts['user'];
 675                         if ( isset( $urlParts['pass'] ) ) {
 676                                 $result .= ':' . $urlParts['pass'];
 677                         }
 678                         $result .= '@';
 679                 }
 680
 681                 $result .= $urlParts['host'];
 682
 683                 if ( isset( $urlParts['port'] ) ) {
 684                         $result .= ':' . $urlParts['port'];
 685                 }
 686         }
 687
 688         if ( isset( $urlParts['path'] ) ) {
 689                 $result .= $urlParts['path'];
 690         }
 691
 692         if ( isset( $urlParts['query'] ) ) {
 693                 $result .= '?' . $urlParts['query'];
 694         }
 695
 696         if ( isset( $urlParts['fragment'] ) ) {
 697                 $result .= '#' . $urlParts['fragment'];
 698         }
 699
 700         return $result;
 701 }
 702
 703 /**
 704  * Remove all dot-segments in the provided URL path.  For example,
 705  * '/a/./b/../c/' becomes '/a/c/'.  For details on the algorithm, please see
 706  * RFC3986 section 5.2.4.
 707  *
 708  * @todo Need to integrate this into wfExpandUrl (see T34168)
 709  *
 710  * @param string $urlPath URL path, potentially containing dot-segments
 711  * @return string URL path with all dot-segments removed
 712  */
 713 function wfRemoveDotSegments( $urlPath ) {
 714         $output = '';
 715         $inputOffset = 0;
 716         $inputLength = strlen( $urlPath );
 717
 718         while ( $inputOffset < $inputLength ) {
 719                 $prefixLengthOne = substr( $urlPath, $inputOffset, 1 );
 720                 $prefixLengthTwo = substr( $urlPath, $inputOffset, 2 );
 721                 $prefixLengthThree = substr( $urlPath, $inputOffset, 3 );
 722                 $prefixLengthFour = substr( $urlPath, $inputOffset, 4 );
 723                 $trimOutput = false;
 724
 725                 if ( $prefixLengthTwo == './' ) {
 726                         # Step A, remove leading "./"
 727                         $inputOffset += 2;
 728                 } elseif ( $prefixLengthThree == '../' ) {
 729                         # Step A, remove leading "../"
 730                         $inputOffset += 3;
 731                 } elseif ( ( $prefixLengthTwo == '/.' ) && ( $inputOffset + 2 == $inputLength ) ) {
 732                         # Step B, replace leading "/.$" with "/"
 733                         $inputOffset += 1;
 734                         $urlPath[$inputOffset] = '/';
 735                 } elseif ( $prefixLengthThree == '/./' ) {
 736                         # Step B, replace leading "/./" with "/"
 737                         $inputOffset += 2;
 738                 } elseif ( $prefixLengthThree == '/..' && ( $inputOffset + 3 == $inputLength ) ) {
 739                         # Step C, replace leading "/..$" with "/" and
 740                         # remove last path component in output
 741                         $inputOffset += 2;
 742                         $urlPath[$inputOffset] = '/';
 743                         $trimOutput = true;
 744                 } elseif ( $prefixLengthFour == '/../' ) {
 745                         # Step C, replace leading "/../" with "/" and
 746                         # remove last path component in output
 747                         $inputOffset += 3;
 748                         $trimOutput = true;
 749                 } elseif ( ( $prefixLengthOne == '.' ) && ( $inputOffset + 1 == $inputLength ) ) {
 750                         # Step D, remove "^.$"
 751                         $inputOffset += 1;
 752                 } elseif ( ( $prefixLengthTwo == '..' ) && ( $inputOffset + 2 == $inputLength ) ) {
 753                         # Step D, remove "^..$"
 754                         $inputOffset += 2;
 755                 } else {
 756                         # Step E, move leading path segment to output
 757                         if ( $prefixLengthOne == '/' ) {
 758                                 $slashPos = strpos( $urlPath, '/', $inputOffset + 1 );
 759                         } else {
 760                                 $slashPos = strpos( $urlPath, '/', $inputOffset );
 761                         }
 762                         if ( $slashPos === false ) {
 763                                 $output .= substr( $urlPath, $inputOffset );
 764                                 $inputOffset = $inputLength;
 765                         } else {
 766                                 $output .= substr( $urlPath, $inputOffset, $slashPos - $inputOffset );
 767                                 $inputOffset += $slashPos - $inputOffset;
 768                         }
 769                 }
 770
 771                 if ( $trimOutput ) {
 772                         $slashPos = strrpos( $output, '/' );
 773                         if ( $slashPos === false ) {
 774                                 $output = '';
 775                         } else {
 776                                 $output = substr( $output, 0, $slashPos );
 777                         }
 778                 }
 779         }
 780
 781         return $output;
 782 }
 783
 784 /**
 785  * Returns a regular expression of url protocols
 786  *
 787  * @param bool $includeProtocolRelative If false, remove '//' from the returned protocol list.
 788  *        DO NOT USE this directly, use wfUrlProtocolsWithoutProtRel() instead
 789  * @return string
 790  */
 791 function wfUrlProtocols( $includeProtocolRelative = true ) {
 792         global $wgUrlProtocols;
 793
 794         // Cache return values separately based on $includeProtocolRelative
 795         static $withProtRel = null, $withoutProtRel = null;
 796         $cachedValue = $includeProtocolRelative ? $withProtRel : $withoutProtRel;
 797         if ( !is_null( $cachedValue ) ) {
 798                 return $cachedValue;
 799         }
 800
 801         // Support old-style $wgUrlProtocols strings, for backwards compatibility
 802         // with LocalSettings files from 1.5
 803         if ( is_array( $wgUrlProtocols ) ) {
 804                 $protocols = [];
 805                 foreach ( $wgUrlProtocols as $protocol ) {
 806                         // Filter out '//' if !$includeProtocolRelative
 807                         if ( $includeProtocolRelative || $protocol !== '//' ) {
 808                                 $protocols[] = preg_quote( $protocol, '/' );
 809                         }
 810                 }
 811
 812                 $retval = implode( '|', $protocols );
 813         } else {
 814                 // Ignore $includeProtocolRelative in this case
 815                 // This case exists for pre-1.6 compatibility, and we can safely assume
 816                 // that '//' won't appear in a pre-1.6 config because protocol-relative
 817                 // URLs weren't supported until 1.18
 818                 $retval = $wgUrlProtocols;
 819         }
 820
 821         // Cache return value
 822         if ( $includeProtocolRelative ) {
 823                 $withProtRel = $retval;
 824         } else {
 825                 $withoutProtRel = $retval;
 826         }
 827         return $retval;
 828 }
 829
 830 /**
 831  * Like wfUrlProtocols(), but excludes '//' from the protocol list. Use this if
 832  * you need a regex that matches all URL protocols but does not match protocol-
 833  * relative URLs
 834  * @return string
 835  */
 836 function wfUrlProtocolsWithoutProtRel() {
 837         return wfUrlProtocols( false );
 838 }
 839
 840 /**
 841  * parse_url() work-alike, but non-broken.  Differences:
 842  *
 843  * 1) Does not raise warnings on bad URLs (just returns false).
 844  * 2) Handles protocols that don't use :// (e.g., mailto: and news:, as well as
 845  *    protocol-relative URLs) correctly.
 846  * 3) Adds a "delimiter" element to the array, either '://', ':' or '//' (see (2)).
 847  *
 848  * @param string $url A URL to parse
 849  * @return string[]|bool Bits of the URL in an associative array, per PHP docs, false on failure
 850  */
 851 function wfParseUrl( $url ) {
 852         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
 853
 854         // Protocol-relative URLs are handled really badly by parse_url(). It's so
 855         // bad that the easiest way to handle them is to just prepend 'http:' and
 856         // strip the protocol out later.
 857         $wasRelative = substr( $url, 0, 2 ) == '//';
 858         if ( $wasRelative ) {
 859                 $url = "http:$url";
 860         }
 861         MediaWiki\suppressWarnings();
 862         $bits = parse_url( $url );
 863         MediaWiki\restoreWarnings();
 864         // parse_url() returns an array without scheme for some invalid URLs, e.g.
 865         // parse_url("%0Ahttp://example.com") == [ 'host' => '%0Ahttp', 'path' => 'example.com' ]
 866         if ( !$bits || !isset( $bits['scheme'] ) ) {
 867                 return false;
 868         }
 869
 870         // parse_url() incorrectly handles schemes case-sensitively. Convert it to lowercase.
 871         $bits['scheme'] = strtolower( $bits['scheme'] );
 872
 873         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
 874         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
 875                 $bits['delimiter'] = '://';
 876         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
 877                 $bits['delimiter'] = ':';
 878                 // parse_url detects for news: and mailto: the host part of an url as path
 879                 // We have to correct this wrong detection
 880                 if ( isset( $bits['path'] ) ) {
 881                         $bits['host'] = $bits['path'];
 882                         $bits['path'] = '';
 883                 }
 884         } else {
 885                 return false;
 886         }
 887
 888         /* Provide an empty host for eg. file:/// urls (see T30627) */
 889         if ( !isset( $bits['host'] ) ) {
 890                 $bits['host'] = '';
 891
 892                 // See T47069
 893                 if ( isset( $bits['path'] ) ) {
 894                         /* parse_url loses the third / for file:///c:/ urls (but not on variants) */
 895                         if ( substr( $bits['path'], 0, 1 ) !== '/' ) {
 896                                 $bits['path'] = '/' . $bits['path'];
 897                         }
 898                 } else {
 899                         $bits['path'] = '';
 900                 }
 901         }
 902
 903         // If the URL was protocol-relative, fix scheme and delimiter
 904         if ( $wasRelative ) {
 905                 $bits['scheme'] = '';
 906                 $bits['delimiter'] = '//';
 907         }
 908         return $bits;
 909 }
 910
 911 /**
 912  * Take a URL, make sure it's expanded to fully qualified, and replace any
 913  * encoded non-ASCII Unicode characters with their UTF-8 original forms
 914  * for more compact display and legibility for local audiences.
 915  *
 916  * @todo handle punycode domains too
 917  *
 918  * @param string $url
 919  * @return string
 920  */
 921 function wfExpandIRI( $url ) {
 922         return preg_replace_callback(
 923                 '/((?:%[89A-F][0-9A-F])+)/i',
 924                 'wfExpandIRI_callback',
 925                 wfExpandUrl( $url )
 926         );
 927 }
 928
 929 /**
 930  * Private callback for wfExpandIRI
 931  * @param array $matches
 932  * @return string
 933  */
 934 function wfExpandIRI_callback( $matches ) {
 935         return urldecode( $matches[1] );
 936 }
 937
 938 /**
 939  * Make URL indexes, appropriate for the el_index field of externallinks.
 940  *
 941  * @param string $url
 942  * @return array
 943  */
 944 function wfMakeUrlIndexes( $url ) {
 945         $bits = wfParseUrl( $url );
 946
 947         // Reverse the labels in the hostname, convert to lower case
 948         // For emails reverse domainpart only
 949         if ( $bits['scheme'] == 'mailto' ) {
 950                 $mailparts = explode( '@', $bits['host'], 2 );
 951                 if ( count( $mailparts ) === 2 ) {
 952                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
 953                 } else {
 954                         // No domain specified, don't mangle it
 955                         $domainpart = '';
 956                 }
 957                 $reversedHost = $domainpart . '@' . $mailparts[0];
 958         } else {
 959                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
 960         }
 961         // Add an extra dot to the end
 962         // Why? Is it in wrong place in mailto links?
 963         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
 964                 $reversedHost .= '.';
 965         }
 966         // Reconstruct the pseudo-URL
 967         $prot = $bits['scheme'];
 968         $index = $prot . $bits['delimiter'] . $reversedHost;
 969         // Leave out user and password. Add the port, path, query and fragment
 970         if ( isset( $bits['port'] ) ) {
 971                 $index .= ':' . $bits['port'];
 972         }
 973         if ( isset( $bits['path'] ) ) {
 974                 $index .= $bits['path'];
 975         } else {
 976                 $index .= '/';
 977         }
 978         if ( isset( $bits['query'] ) ) {
 979                 $index .= '?' . $bits['query'];
 980         }
 981         if ( isset( $bits['fragment'] ) ) {
 982                 $index .= '#' . $bits['fragment'];
 983         }
 984
 985         if ( $prot == '' ) {
 986                 return [ "http:$index", "https:$index" ];
 987         } else {
 988                 return [ $index ];
 989         }
 990 }
 991
 992 /**
 993  * Check whether a given URL has a domain that occurs in a given set of domains
 994  * @param string $url URL
 995  * @param array $domains Array of domains (strings)
 996  * @return bool True if the host part of $url ends in one of the strings in $domains
 997  */
 998 function wfMatchesDomainList( $url, $domains ) {
 999         $bits = wfParseUrl( $url );
1000         if ( is_array( $bits ) && isset( $bits['host'] ) ) {
1001                 $host = '.' . $bits['host'];
1002                 foreach ( (array)$domains as $domain ) {
1003                         $domain = '.' . $domain;
1004                         if ( substr( $host, -strlen( $domain ) ) === $domain ) {
1005                                 return true;
1006                         }
1007                 }
1008         }
1009         return false;
1010 }
1011
1012 /**
1013  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
1014  * In normal operation this is a NOP.
1015  *
1016  * Controlling globals:
1017  * $wgDebugLogFile - points to the log file
1018  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
1019  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
1020  *
1021  * @since 1.25 support for additional context data
1022  *
1023  * @param string $text
1024  * @param string|bool $dest Destination of the message:
1025  *     - 'all': both to the log and HTML (debug toolbar or HTML comments)
1026  *     - 'private': excluded from HTML output
1027  *   For backward compatibility, it can also take a boolean:
1028  *     - true: same as 'all'
1029  *     - false: same as 'private'
1030  * @param array $context Additional logging context data
1031  */
1032 function wfDebug( $text, $dest = 'all', array $context = [] ) {
1033         global $wgDebugRawPage, $wgDebugLogPrefix;
1034         global $wgDebugTimestamps, $wgRequestTime;
1035
1036         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
1037                 return;
1038         }
1039
1040         $text = trim( $text );
1041
1042         if ( $wgDebugTimestamps ) {
1043                 $context['seconds_elapsed'] = sprintf(
1044                         '%6.4f',
1045                         microtime( true ) - $wgRequestTime
1046                 );
1047                 $context['memory_used'] = sprintf(
1048                         '%5.1fM',
1049                         ( memory_get_usage( true ) / ( 1024 * 1024 ) )
1050                 );
1051         }
1052
1053         if ( $wgDebugLogPrefix !== '' ) {
1054                 $context['prefix'] = $wgDebugLogPrefix;
1055         }
1056         $context['private'] = ( $dest === false || $dest === 'private' );
1057
1058         $logger = LoggerFactory::getInstance( 'wfDebug' );
1059         $logger->debug( $text, $context );
1060 }
1061
1062 /**
1063  * Returns true if debug logging should be suppressed if $wgDebugRawPage = false
1064  * @return bool
1065  */
1066 function wfIsDebugRawPage() {
1067         static $cache;
1068         if ( $cache !== null ) {
1069                 return $cache;
1070         }
1071         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
1072         if ( ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' )
1073                 || (
1074                         isset( $_SERVER['SCRIPT_NAME'] )
1075                         && substr( $_SERVER['SCRIPT_NAME'], -8 ) == 'load.php'
1076                 )
1077         ) {
1078                 $cache = true;
1079         } else {
1080                 $cache = false;
1081         }
1082         return $cache;
1083 }
1084
1085 /**
1086  * Send a line giving PHP memory usage.
1087  *
1088  * @param bool $exact Print exact byte values instead of kibibytes (default: false)
1089  */
1090 function wfDebugMem( $exact = false ) {
1091         $mem = memory_get_usage();
1092         if ( !$exact ) {
1093                 $mem = floor( $mem / 1024 ) . ' KiB';
1094         } else {
1095                 $mem .= ' B';
1096         }
1097         wfDebug( "Memory usage: $mem\n" );
1098 }
1099
1100 /**
1101  * Send a line to a supplementary debug log file, if configured, or main debug
1102  * log if not.
1103  *
1104  * To configure a supplementary log file, set $wgDebugLogGroups[$logGroup] to
1105  * a string filename or an associative array mapping 'destination' to the
1106  * desired filename. The associative array may also contain a 'sample' key
1107  * with an integer value, specifying a sampling factor. Sampled log events
1108  * will be emitted with a 1 in N random chance.
1109  *
1110  * @since 1.23 support for sampling log messages via $wgDebugLogGroups.
1111  * @since 1.25 support for additional context data
1112  * @since 1.25 sample behavior dependent on configured $wgMWLoggerDefaultSpi
1113  *
1114  * @param string $logGroup
1115  * @param string $text
1116  * @param string|bool $dest Destination of the message:
1117  *     - 'all': both to the log and HTML (debug toolbar or HTML comments)
1118  *     - 'private': only to the specific log if set in $wgDebugLogGroups and
1119  *       discarded otherwise
1120  *   For backward compatibility, it can also take a boolean:
1121  *     - true: same as 'all'
1122  *     - false: same as 'private'
1123  * @param array $context Additional logging context data
1124  */
1125 function wfDebugLog(
1126         $logGroup, $text, $dest = 'all', array $context = []
1127 ) {
1128         $text = trim( $text );
1129
1130         $logger = LoggerFactory::getInstance( $logGroup );
1131         $context['private'] = ( $dest === false || $dest === 'private' );
1132         $logger->info( $text, $context );
1133 }
1134
1135 /**
1136  * Log for database errors
1137  *
1138  * @since 1.25 support for additional context data
1139  *
1140  * @param string $text Database error message.
1141  * @param array $context Additional logging context data
1142  */
1143 function wfLogDBError( $text, array $context = [] ) {
1144         $logger = LoggerFactory::getInstance( 'wfLogDBError' );
1145         $logger->error( trim( $text ), $context );
1146 }
1147
1148 /**
1149  * Throws a warning that $function is deprecated
1150  *
1151  * @param string $function
1152  * @param string|bool $version Version of MediaWiki that the function
1153  *    was deprecated in (Added in 1.19).
1154  * @param string|bool $component Added in 1.19.
1155  * @param int $callerOffset How far up the call stack is the original
1156  *    caller. 2 = function that called the function that called
1157  *    wfDeprecated (Added in 1.20)
1158  *
1159  * @return null
1160  */
1161 function wfDeprecated( $function, $version = false, $component = false, $callerOffset = 2 ) {
1162         MWDebug::deprecated( $function, $version, $component, $callerOffset + 1 );
1163 }
1164
1165 /**
1166  * Send a warning either to the debug log or in a PHP error depending on
1167  * $wgDevelopmentWarnings. To log warnings in production, use wfLogWarning() instead.
1168  *
1169  * @param string $msg Message to send
1170  * @param int $callerOffset Number of items to go back in the backtrace to
1171  *        find the correct caller (1 = function calling wfWarn, ...)
1172  * @param int $level PHP error level; defaults to E_USER_NOTICE;
1173  *        only used when $wgDevelopmentWarnings is true
1174  */
1175 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
1176         MWDebug::warning( $msg, $callerOffset + 1, $level, 'auto' );
1177 }
1178
1179 /**
1180  * Send a warning as a PHP error and the debug log. This is intended for logging
1181  * warnings in production. For logging development warnings, use WfWarn instead.
1182  *
1183  * @param string $msg Message to send
1184  * @param int $callerOffset Number of items to go back in the backtrace to
1185  *        find the correct caller (1 = function calling wfLogWarning, ...)
1186  * @param int $level PHP error level; defaults to E_USER_WARNING
1187  */
1188 function wfLogWarning( $msg, $callerOffset = 1, $level = E_USER_WARNING ) {
1189         MWDebug::warning( $msg, $callerOffset + 1, $level, 'production' );
1190 }
1191
1192 /**
1193  * Log to a file without getting "file size exceeded" signals.
1194  *
1195  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
1196  * send lines to the specified port, prefixed by the specified prefix and a space.
1197  * @since 1.25 support for additional context data
1198  *
1199  * @param string $text
1200  * @param string $file Filename
1201  * @param array $context Additional logging context data
1202  * @throws MWException
1203  * @deprecated since 1.25 Use \MediaWiki\Logger\LegacyLogger::emit or UDPTransport
1204  */
1205 function wfErrorLog( $text, $file, array $context = [] ) {
1206         wfDeprecated( __METHOD__, '1.25' );
1207         $logger = LoggerFactory::getInstance( 'wfErrorLog' );
1208         $context['destination'] = $file;
1209         $logger->info( trim( $text ), $context );
1210 }
1211
1212 /**
1213  * @todo document
1214  */
1215 function wfLogProfilingData() {
1216         global $wgDebugLogGroups, $wgDebugRawPage;
1217
1218         $context = RequestContext::getMain();
1219         $request = $context->getRequest();
1220
1221         $profiler = Profiler::instance();
1222         $profiler->setContext( $context );
1223         $profiler->logData();
1224
1225         $config = $context->getConfig();
1226         $stats = MediaWikiServices::getInstance()->getStatsdDataFactory();
1227         if ( $config->get( 'StatsdServer' ) && $stats->hasData() ) {
1228                 try {
1229                         $statsdServer = explode( ':', $config->get( 'StatsdServer' ) );
1230                         $statsdHost = $statsdServer[0];
1231                         $statsdPort = isset( $statsdServer[1] ) ? $statsdServer[1] : 8125;
1232                         $statsdSender = new SocketSender( $statsdHost, $statsdPort );
1233                         $statsdClient = new SamplingStatsdClient( $statsdSender, true, false );
1234                         $statsdClient->setSamplingRates( $config->get( 'StatsdSamplingRates' ) );
1235                         $statsdClient->send( $stats->getData() );
1236                 } catch ( Exception $ex ) {
1237                         MWExceptionHandler::logException( $ex );
1238                 }
1239         }
1240
1241         # Profiling must actually be enabled...
1242         if ( $profiler instanceof ProfilerStub ) {
1243                 return;
1244         }
1245
1246         if ( isset( $wgDebugLogGroups['profileoutput'] )
1247                 && $wgDebugLogGroups['profileoutput'] === false
1248         ) {
1249                 // Explicitly disabled
1250                 return;
1251         }
1252         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
1253                 return;
1254         }
1255
1256         $ctx = [ 'elapsed' => $request->getElapsedTime() ];
1257         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
1258                 $ctx['forwarded_for'] = $_SERVER['HTTP_X_FORWARDED_FOR'];
1259         }
1260         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
1261                 $ctx['client_ip'] = $_SERVER['HTTP_CLIENT_IP'];
1262         }
1263         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
1264                 $ctx['from'] = $_SERVER['HTTP_FROM'];
1265         }
1266         if ( isset( $ctx['forwarded_for'] ) ||
1267                 isset( $ctx['client_ip'] ) ||
1268                 isset( $ctx['from'] ) ) {
1269                 $ctx['proxy'] = $_SERVER['REMOTE_ADDR'];
1270         }
1271
1272         // Don't load $wgUser at this late stage just for statistics purposes
1273         // @todo FIXME: We can detect some anons even if it is not loaded.
1274         // See User::getId()
1275         $user = $context->getUser();
1276         $ctx['anon'] = $user->isItemLoaded( 'id' ) && $user->isAnon();
1277
1278         // Command line script uses a FauxRequest object which does not have
1279         // any knowledge about an URL and throw an exception instead.
1280         try {
1281                 $ctx['url'] = urldecode( $request->getRequestURL() );
1282         } catch ( Exception $ignored ) {
1283                 // no-op
1284         }
1285
1286         $ctx['output'] = $profiler->getOutput();
1287
1288         $log = LoggerFactory::getInstance( 'profileoutput' );
1289         $log->info( "Elapsed: {elapsed}; URL: <{url}>\n{output}", $ctx );
1290 }
1291
1292 /**
1293  * Increment a statistics counter
1294  *
1295  * @param string $key
1296  * @param int $count
1297  * @return void
1298  */
1299 function wfIncrStats( $key, $count = 1 ) {
1300         $stats = MediaWikiServices::getInstance()->getStatsdDataFactory();
1301         $stats->updateCount( $key, $count );
1302 }
1303
1304 /**
1305  * Check whether the wiki is in read-only mode.
1306  *
1307  * @return bool
1308  */
1309 function wfReadOnly() {
1310         return MediaWikiServices::getInstance()->getReadOnlyMode()
1311                 ->isReadOnly();
1312 }
1313
1314 /**
1315  * Check if the site is in read-only mode and return the message if so
1316  *
1317  * This checks wfConfiguredReadOnlyReason() and the main load balancer
1318  * for replica DB lag. This may result in DB connection being made.
1319  *
1320  * @return string|bool String when in read-only mode; false otherwise
1321  */
1322 function wfReadOnlyReason() {
1323         return MediaWikiServices::getInstance()->getReadOnlyMode()
1324                 ->getReason();
1325 }
1326
1327 /**
1328  * Get the value of $wgReadOnly or the contents of $wgReadOnlyFile.
1329  *
1330  * @return string|bool String when in read-only mode; false otherwise
1331  * @since 1.27
1332  */
1333 function wfConfiguredReadOnlyReason() {
1334         return MediaWikiServices::getInstance()->getConfiguredReadOnlyMode()
1335                 ->getReason();
1336 }
1337
1338 /**
1339  * Return a Language object from $langcode
1340  *
1341  * @param Language|string|bool $langcode Either:
1342  *                  - a Language object
1343  *                  - code of the language to get the message for, if it is
1344  *                    a valid code create a language for that language, if
1345  *                    it is a string but not a valid code then make a basic
1346  *                    language object
1347  *                  - a boolean: if it's false then use the global object for
1348  *                    the current user's language (as a fallback for the old parameter
1349  *                    functionality), or if it is true then use global object
1350  *                    for the wiki's content language.
1351  * @return Language
1352  */
1353 function wfGetLangObj( $langcode = false ) {
1354         # Identify which language to get or create a language object for.
1355         # Using is_object here due to Stub objects.
1356         if ( is_object( $langcode ) ) {
1357                 # Great, we already have the object (hopefully)!
1358                 return $langcode;
1359         }
1360
1361         global $wgContLang, $wgLanguageCode;
1362         if ( $langcode === true || $langcode === $wgLanguageCode ) {
1363                 # $langcode is the language code of the wikis content language object.
1364                 # or it is a boolean and value is true
1365                 return $wgContLang;
1366         }
1367
1368         global $wgLang;
1369         if ( $langcode === false || $langcode === $wgLang->getCode() ) {
1370                 # $langcode is the language code of user language object.
1371                 # or it was a boolean and value is false
1372                 return $wgLang;
1373         }
1374
1375         $validCodes = array_keys( Language::fetchLanguageNames() );
1376         if ( in_array( $langcode, $validCodes ) ) {
1377                 # $langcode corresponds to a valid language.
1378                 return Language::factory( $langcode );
1379         }
1380
1381         # $langcode is a string, but not a valid language code; use content language.
1382         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
1383         return $wgContLang;
1384 }
1385
1386 /**
1387  * This is the function for getting translated interface messages.
1388  *
1389  * @see Message class for documentation how to use them.
1390  * @see https://www.mediawiki.org/wiki/Manual:Messages_API
1391  *
1392  * This function replaces all old wfMsg* functions.
1393  *
1394  * @param string|string[]|MessageSpecifier $key Message key, or array of keys, or a MessageSpecifier
1395  * @param mixed $params,... Normal message parameters
1396  * @return Message
1397  *
1398  * @since 1.17
1399  *
1400  * @see Message::__construct
1401  */
1402 function wfMessage( $key /*...*/ ) {
1403         $message = new Message( $key );
1404
1405         // We call Message::params() to reduce code duplication
1406         $params = func_get_args();
1407         array_shift( $params );
1408         if ( $params ) {
1409                 call_user_func_array( [ $message, 'params' ], $params );
1410         }
1411
1412         return $message;
1413 }
1414
1415 /**
1416  * This function accepts multiple message keys and returns a message instance
1417  * for the first message which is non-empty. If all messages are empty then an
1418  * instance of the first message key is returned.
1419  *
1420  * @param string|string[] $keys,... Message keys
1421  * @return Message
1422  *
1423  * @since 1.18
1424  *
1425  * @see Message::newFallbackSequence
1426  */
1427 function wfMessageFallback( /*...*/ ) {
1428         $args = func_get_args();
1429         return call_user_func_array( 'Message::newFallbackSequence', $args );
1430 }
1431
1432 /**
1433  * Replace message parameter keys on the given formatted output.
1434  *
1435  * @param string $message
1436  * @param array $args
1437  * @return string
1438  * @private
1439  */
1440 function wfMsgReplaceArgs( $message, $args ) {
1441         # Fix windows line-endings
1442         # Some messages are split with explode("\n", $msg)
1443         $message = str_replace( "\r", '', $message );
1444
1445         // Replace arguments
1446         if ( is_array( $args ) && $args ) {
1447                 if ( is_array( $args[0] ) ) {
1448                         $args = array_values( $args[0] );
1449                 }
1450                 $replacementKeys = [];
1451                 foreach ( $args as $n => $param ) {
1452                         $replacementKeys['$' . ( $n + 1 )] = $param;
1453                 }
1454                 $message = strtr( $message, $replacementKeys );
1455         }
1456
1457         return $message;
1458 }
1459
1460 /**
1461  * Fetch server name for use in error reporting etc.
1462  * Use real server name if available, so we know which machine
1463  * in a server farm generated the current page.
1464  *
1465  * @return string
1466  */
1467 function wfHostname() {
1468         static $host;
1469         if ( is_null( $host ) ) {
1470                 # Hostname overriding
1471                 global $wgOverrideHostname;
1472                 if ( $wgOverrideHostname !== false ) {
1473                         # Set static and skip any detection
1474                         $host = $wgOverrideHostname;
1475                         return $host;
1476                 }
1477
1478                 if ( function_exists( 'posix_uname' ) ) {
1479                         // This function not present on Windows
1480                         $uname = posix_uname();
1481                 } else {
1482                         $uname = false;
1483                 }
1484                 if ( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1485                         $host = $uname['nodename'];
1486                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1487                         # Windows computer name
1488                         $host = getenv( 'COMPUTERNAME' );
1489                 } else {
1490                         # This may be a virtual server.
1491                         $host = $_SERVER['SERVER_NAME'];
1492                 }
1493         }
1494         return $host;
1495 }
1496
1497 /**
1498  * Returns a script tag that stores the amount of time it took MediaWiki to
1499  * handle the request in milliseconds as 'wgBackendResponseTime'.
1500  *
1501  * If $wgShowHostnames is true, the script will also set 'wgHostname' to the
1502  * hostname of the server handling the request.
1503  *
1504  * @return string
1505  */
1506 function wfReportTime() {
1507         global $wgRequestTime, $wgShowHostnames;
1508
1509         $responseTime = round( ( microtime( true ) - $wgRequestTime ) * 1000 );
1510         $reportVars = [ 'wgBackendResponseTime' => $responseTime ];
1511         if ( $wgShowHostnames ) {
1512                 $reportVars['wgHostname'] = wfHostname();
1513         }
1514         return Skin::makeVariablesScript( $reportVars );
1515 }
1516
1517 /**
1518  * Safety wrapper for debug_backtrace().
1519  *
1520  * Will return an empty array if debug_backtrace is disabled, otherwise
1521  * the output from debug_backtrace() (trimmed).
1522  *
1523  * @param int $limit This parameter can be used to limit the number of stack frames returned
1524  *
1525  * @return array Array of backtrace information
1526  */
1527 function wfDebugBacktrace( $limit = 0 ) {
1528         static $disabled = null;
1529
1530         if ( is_null( $disabled ) ) {
1531                 $disabled = !function_exists( 'debug_backtrace' );
1532                 if ( $disabled ) {
1533                         wfDebug( "debug_backtrace() is disabled\n" );
1534                 }
1535         }
1536         if ( $disabled ) {
1537                 return [];
1538         }
1539
1540         if ( $limit ) {
1541                 return array_slice( debug_backtrace( DEBUG_BACKTRACE_PROVIDE_OBJECT, $limit + 1 ), 1 );
1542         } else {
1543                 return array_slice( debug_backtrace(), 1 );
1544         }
1545 }
1546
1547 /**
1548  * Get a debug backtrace as a string
1549  *
1550  * @param bool|null $raw If true, the return value is plain text. If false, HTML.
1551  *   Defaults to $wgCommandLineMode if unset.
1552  * @return string
1553  * @since 1.25 Supports $raw parameter.
1554  */
1555 function wfBacktrace( $raw = null ) {
1556         global $wgCommandLineMode;
1557
1558         if ( $raw === null ) {
1559                 $raw = $wgCommandLineMode;
1560         }
1561
1562         if ( $raw ) {
1563                 $frameFormat = "%s line %s calls %s()\n";
1564                 $traceFormat = "%s";
1565         } else {
1566                 $frameFormat = "<li>%s line %s calls %s()</li>\n";
1567                 $traceFormat = "<ul>\n%s</ul>\n";
1568         }
1569
1570         $frames = array_map( function ( $frame ) use ( $frameFormat ) {
1571                 $file = !empty( $frame['file'] ) ? basename( $frame['file'] ) : '-';
1572                 $line = isset( $frame['line'] ) ? $frame['line'] : '-';
1573                 $call = $frame['function'];
1574                 if ( !empty( $frame['class'] ) ) {
1575                         $call = $frame['class'] . $frame['type'] . $call;
1576                 }
1577                 return sprintf( $frameFormat, $file, $line, $call );
1578         }, wfDebugBacktrace() );
1579
1580         return sprintf( $traceFormat, implode( '', $frames ) );
1581 }
1582
1583 /**
1584  * Get the name of the function which called this function
1585  * wfGetCaller( 1 ) is the function with the wfGetCaller() call (ie. __FUNCTION__)
1586  * wfGetCaller( 2 ) [default] is the caller of the function running wfGetCaller()
1587  * wfGetCaller( 3 ) is the parent of that.
1588  *
1589  * @param int $level
1590  * @return string
1591  */
1592 function wfGetCaller( $level = 2 ) {
1593         $backtrace = wfDebugBacktrace( $level + 1 );
1594         if ( isset( $backtrace[$level] ) ) {
1595                 return wfFormatStackFrame( $backtrace[$level] );
1596         } else {
1597                 return 'unknown';
1598         }
1599 }
1600
1601 /**
1602  * Return a string consisting of callers in the stack. Useful sometimes
1603  * for profiling specific points.
1604  *
1605  * @param int $limit The maximum depth of the stack frame to return, or false for the entire stack.
1606  * @return string
1607  */
1608 function wfGetAllCallers( $limit = 3 ) {
1609         $trace = array_reverse( wfDebugBacktrace() );
1610         if ( !$limit || $limit > count( $trace ) - 1 ) {
1611                 $limit = count( $trace ) - 1;
1612         }
1613         $trace = array_slice( $trace, -$limit - 1, $limit );
1614         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1615 }
1616
1617 /**
1618  * Return a string representation of frame
1619  *
1620  * @param array $frame
1621  * @return string
1622  */
1623 function wfFormatStackFrame( $frame ) {
1624         if ( !isset( $frame['function'] ) ) {
1625                 return 'NO_FUNCTION_GIVEN';
1626         }
1627         return isset( $frame['class'] ) && isset( $frame['type'] ) ?
1628                 $frame['class'] . $frame['type'] . $frame['function'] :
1629                 $frame['function'];
1630 }
1631
1632 /* Some generic result counters, pulled out of SearchEngine */
1633
1634 /**
1635  * @todo document
1636  *
1637  * @param int $offset
1638  * @param int $limit
1639  * @return string
1640  */
1641 function wfShowingResults( $offset, $limit ) {
1642         return wfMessage( 'showingresults' )->numParams( $limit, $offset + 1 )->parse();
1643 }
1644
1645 /**
1646  * Whether the client accept gzip encoding
1647  *
1648  * Uses the Accept-Encoding header to check if the client supports gzip encoding.
1649  * Use this when considering to send a gzip-encoded response to the client.
1650  *
1651  * @param bool $force Forces another check even if we already have a cached result.
1652  * @return bool
1653  */
1654 function wfClientAcceptsGzip( $force = false ) {
1655         static $result = null;
1656         if ( $result === null || $force ) {
1657                 $result = false;
1658                 if ( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1659                         # @todo FIXME: We may want to blacklist some broken browsers
1660                         $m = [];
1661                         if ( preg_match(
1662                                         '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1663                                         $_SERVER['HTTP_ACCEPT_ENCODING'],
1664                                         $m
1665                                 )
1666                         ) {
1667                                 if ( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1668                                         $result = false;
1669                                         return $result;
1670                                 }
1671                                 wfDebug( "wfClientAcceptsGzip: client accepts gzip.\n" );
1672                                 $result = true;
1673                         }
1674                 }
1675         }
1676         return $result;
1677 }
1678
1679 /**
1680  * Escapes the given text so that it may be output using addWikiText()
1681  * without any linking, formatting, etc. making its way through. This
1682  * is achieved by substituting certain characters with HTML entities.
1683  * As required by the callers, "<nowiki>" is not used.
1684  *
1685  * @param string $text Text to be escaped
1686  * @return string
1687  */
1688 function wfEscapeWikiText( $text ) {
1689         global $wgEnableMagicLinks;
1690         static $repl = null, $repl2 = null;
1691         if ( $repl === null || defined( 'MW_PARSER_TEST' ) || defined( 'MW_PHPUNIT_TEST' ) ) {
1692                 // Tests depend upon being able to change $wgEnableMagicLinks, so don't cache
1693                 // in those situations
1694                 $repl = [
1695                         '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
1696                         '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
1697                         '{' => '&#123;', '|' => '&#124;', '}' => '&#125;', ';' => '&#59;',
1698                         "\n#" => "\n&#35;", "\r#" => "\r&#35;",
1699                         "\n*" => "\n&#42;", "\r*" => "\r&#42;",
1700                         "\n:" => "\n&#58;", "\r:" => "\r&#58;",
1701                         "\n " => "\n&#32;", "\r " => "\r&#32;",
1702                         "\n\n" => "\n&#10;", "\r\n" => "&#13;\n",
1703                         "\n\r" => "\n&#13;", "\r\r" => "\r&#13;",
1704                         "\n\t" => "\n&#9;", "\r\t" => "\r&#9;", // "\n\t\n" is treated like "\n\n"
1705                         "\n----" => "\n&#45;---", "\r----" => "\r&#45;---",
1706                         '__' => '_&#95;', '://' => '&#58;//',
1707                 ];
1708
1709                 $magicLinks = array_keys( array_filter( $wgEnableMagicLinks ) );
1710                 // We have to catch everything "\s" matches in PCRE
1711                 foreach ( $magicLinks as $magic ) {
1712                         $repl["$magic "] = "$magic&#32;";
1713                         $repl["$magic\t"] = "$magic&#9;";
1714                         $repl["$magic\r"] = "$magic&#13;";
1715                         $repl["$magic\n"] = "$magic&#10;";
1716                         $repl["$magic\f"] = "$magic&#12;";
1717                 }
1718
1719                 // And handle protocols that don't use "://"
1720                 global $wgUrlProtocols;
1721                 $repl2 = [];
1722                 foreach ( $wgUrlProtocols as $prot ) {
1723                         if ( substr( $prot, -1 ) === ':' ) {
1724                                 $repl2[] = preg_quote( substr( $prot, 0, -1 ), '/' );
1725                         }
1726                 }
1727                 $repl2 = $repl2 ? '/\b(' . implode( '|', $repl2 ) . '):/i' : '/^(?!)/';
1728         }
1729         $text = substr( strtr( "\n$text", $repl ), 1 );
1730         $text = preg_replace( $repl2, '$1&#58;', $text );
1731         return $text;
1732 }
1733
1734 /**
1735  * Sets dest to source and returns the original value of dest
1736  * If source is NULL, it just returns the value, it doesn't set the variable
1737  * If force is true, it will set the value even if source is NULL
1738  *
1739  * @param mixed $dest
1740  * @param mixed $source
1741  * @param bool $force
1742  * @return mixed
1743  */
1744 function wfSetVar( &$dest, $source, $force = false ) {
1745         $temp = $dest;
1746         if ( !is_null( $source ) || $force ) {
1747                 $dest = $source;
1748         }
1749         return $temp;
1750 }
1751
1752 /**
1753  * As for wfSetVar except setting a bit
1754  *
1755  * @param int $dest
1756  * @param int $bit
1757  * @param bool $state
1758  *
1759  * @return bool
1760  */
1761 function wfSetBit( &$dest, $bit, $state = true ) {
1762         $temp = (bool)( $dest & $bit );
1763         if ( !is_null( $state ) ) {
1764                 if ( $state ) {
1765                         $dest |= $bit;
1766                 } else {
1767                         $dest &= ~$bit;
1768                 }
1769         }
1770         return $temp;
1771 }
1772
1773 /**
1774  * A wrapper around the PHP function var_export().
1775  * Either print it or add it to the regular output ($wgOut).
1776  *
1777  * @param mixed $var A PHP variable to dump.
1778  */
1779 function wfVarDump( $var ) {
1780         global $wgOut;
1781         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
1782         if ( headers_sent() || !isset( $wgOut ) || !is_object( $wgOut ) ) {
1783                 print $s;
1784         } else {
1785                 $wgOut->addHTML( $s );
1786         }
1787 }
1788
1789 /**
1790  * Provide a simple HTTP error.
1791  *
1792  * @param int|string $code
1793  * @param string $label
1794  * @param string $desc
1795  */
1796 function wfHttpError( $code, $label, $desc ) {
1797         global $wgOut;
1798         HttpStatus::header( $code );
1799         if ( $wgOut ) {
1800                 $wgOut->disable();
1801                 $wgOut->sendCacheControl();
1802         }
1803
1804         MediaWiki\HeaderCallback::warnIfHeadersSent();
1805         header( 'Content-type: text/html; charset=utf-8' );
1806         print '<!DOCTYPE html>' .
1807                 '<html><head><title>' .
1808                 htmlspecialchars( $label ) .
1809                 '</title></head><body><h1>' .
1810                 htmlspecialchars( $label ) .
1811                 '</h1><p>' .
1812                 nl2br( htmlspecialchars( $desc ) ) .
1813                 "</p></body></html>\n";
1814 }
1815
1816 /**
1817  * Clear away any user-level output buffers, discarding contents.
1818  *
1819  * Suitable for 'starting afresh', for instance when streaming
1820  * relatively large amounts of data without buffering, or wanting to
1821  * output image files without ob_gzhandler's compression.
1822  *
1823  * The optional $resetGzipEncoding parameter controls suppression of
1824  * the Content-Encoding header sent by ob_gzhandler; by default it
1825  * is left. See comments for wfClearOutputBuffers() for why it would
1826  * be used.
1827  *
1828  * Note that some PHP configuration options may add output buffer
1829  * layers which cannot be removed; these are left in place.
1830  *
1831  * @param bool $resetGzipEncoding
1832  */
1833 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
1834         if ( $resetGzipEncoding ) {
1835                 // Suppress Content-Encoding and Content-Length
1836                 // headers from 1.10+s wfOutputHandler
1837                 global $wgDisableOutputCompression;
1838                 $wgDisableOutputCompression = true;
1839         }
1840         while ( $status = ob_get_status() ) {
1841                 if ( isset( $status['flags'] ) ) {
1842                         $flags = PHP_OUTPUT_HANDLER_CLEANABLE | PHP_OUTPUT_HANDLER_REMOVABLE;
1843                         $deleteable = ( $status['flags'] & $flags ) === $flags;
1844                 } elseif ( isset( $status['del'] ) ) {
1845                         $deleteable = $status['del'];
1846                 } else {
1847                         // Guess that any PHP-internal setting can't be removed.
1848                         $deleteable = $status['type'] !== 0; /* PHP_OUTPUT_HANDLER_INTERNAL */
1849                 }
1850                 if ( !$deleteable ) {
1851                         // Give up, and hope the result doesn't break
1852                         // output behavior.
1853                         break;
1854                 }
1855                 if ( $status['name'] === 'MediaWikiTestCase::wfResetOutputBuffersBarrier' ) {
1856                         // Unit testing barrier to prevent this function from breaking PHPUnit.
1857                         break;
1858                 }
1859                 if ( !ob_end_clean() ) {
1860                         // Could not remove output buffer handler; abort now
1861                         // to avoid getting in some kind of infinite loop.
1862                         break;
1863                 }
1864                 if ( $resetGzipEncoding ) {
1865                         if ( $status['name'] == 'ob_gzhandler' ) {
1866                                 // Reset the 'Content-Encoding' field set by this handler
1867                                 // so we can start fresh.
1868                                 header_remove( 'Content-Encoding' );
1869                                 break;
1870                         }
1871                 }
1872         }
1873 }
1874
1875 /**
1876  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
1877  *
1878  * Clear away output buffers, but keep the Content-Encoding header
1879  * produced by ob_gzhandler, if any.
1880  *
1881  * This should be used for HTTP 304 responses, where you need to
1882  * preserve the Content-Encoding header of the real result, but
1883  * also need to suppress the output of ob_gzhandler to keep to spec
1884  * and avoid breaking Firefox in rare cases where the headers and
1885  * body are broken over two packets.
1886  */
1887 function wfClearOutputBuffers() {
1888         wfResetOutputBuffers( false );
1889 }
1890
1891 /**
1892  * Converts an Accept-* header into an array mapping string values to quality
1893  * factors
1894  *
1895  * @param string $accept
1896  * @param string $def Default
1897  * @return float[] Associative array of string => float pairs
1898  */
1899 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
1900         # No arg means accept anything (per HTTP spec)
1901         if ( !$accept ) {
1902                 return [ $def => 1.0 ];
1903         }
1904
1905         $prefs = [];
1906
1907         $parts = explode( ',', $accept );
1908
1909         foreach ( $parts as $part ) {
1910                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
1911                 $values = explode( ';', trim( $part ) );
1912                 $match = [];
1913                 if ( count( $values ) == 1 ) {
1914                         $prefs[$values[0]] = 1.0;
1915                 } elseif ( preg_match( '/q\s*=\s*(\d*\.\d+)/', $values[1], $match ) ) {
1916                         $prefs[$values[0]] = floatval( $match[1] );
1917                 }
1918         }
1919
1920         return $prefs;
1921 }
1922
1923 /**
1924  * Checks if a given MIME type matches any of the keys in the given
1925  * array. Basic wildcards are accepted in the array keys.
1926  *
1927  * Returns the matching MIME type (or wildcard) if a match, otherwise
1928  * NULL if no match.
1929  *
1930  * @param string $type
1931  * @param array $avail
1932  * @return string
1933  * @private
1934  */
1935 function mimeTypeMatch( $type, $avail ) {
1936         if ( array_key_exists( $type, $avail ) ) {
1937                 return $type;
1938         } else {
1939                 $mainType = explode( '/', $type )[0];
1940                 if ( array_key_exists( "$mainType/*", $avail ) ) {
1941                         return "$mainType/*";
1942                 } elseif ( array_key_exists( '*/*', $avail ) ) {
1943                         return '*/*';
1944                 } else {
1945                         return null;
1946                 }
1947         }
1948 }
1949
1950 /**
1951  * Returns the 'best' match between a client's requested internet media types
1952  * and the server's list of available types. Each list should be an associative
1953  * array of type to preference (preference is a float between 0.0 and 1.0).
1954  * Wildcards in the types are acceptable.
1955  *
1956  * @param array $cprefs Client's acceptable type list
1957  * @param array $sprefs Server's offered types
1958  * @return string
1959  *
1960  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
1961  * XXX: generalize to negotiate other stuff
1962  */
1963 function wfNegotiateType( $cprefs, $sprefs ) {
1964         $combine = [];
1965
1966         foreach ( array_keys( $sprefs ) as $type ) {
1967                 $subType = explode( '/', $type )[1];
1968                 if ( $subType != '*' ) {
1969                         $ckey = mimeTypeMatch( $type, $cprefs );
1970                         if ( $ckey ) {
1971                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
1972                         }
1973                 }
1974         }
1975
1976         foreach ( array_keys( $cprefs ) as $type ) {
1977                 $subType = explode( '/', $type )[1];
1978                 if ( $subType != '*' && !array_key_exists( $type, $sprefs ) ) {
1979                         $skey = mimeTypeMatch( $type, $sprefs );
1980                         if ( $skey ) {
1981                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
1982                         }
1983                 }
1984         }
1985
1986         $bestq = 0;
1987         $besttype = null;
1988
1989         foreach ( array_keys( $combine ) as $type ) {
1990                 if ( $combine[$type] > $bestq ) {
1991                         $besttype = $type;
1992                         $bestq = $combine[$type];
1993                 }
1994         }
1995
1996         return $besttype;
1997 }
1998
1999 /**
2000  * Reference-counted warning suppression
2001  *
2002  * @deprecated since 1.26, use MediaWiki\suppressWarnings() directly
2003  * @param bool $end
2004  */
2005 function wfSuppressWarnings( $end = false ) {
2006         MediaWiki\suppressWarnings( $end );
2007 }
2008
2009 /**
2010  * @deprecated since 1.26, use MediaWiki\restoreWarnings() directly
2011  * Restore error level to previous value
2012  */
2013 function wfRestoreWarnings() {
2014         MediaWiki\suppressWarnings( true );
2015 }
2016
2017 /**
2018  * Get a timestamp string in one of various formats
2019  *
2020  * @param mixed $outputtype A timestamp in one of the supported formats, the
2021  *   function will autodetect which format is supplied and act accordingly.
2022  * @param mixed $ts Optional timestamp to convert, default 0 for the current time
2023  * @return string|bool String / false The same date in the format specified in $outputtype or false
2024  */
2025 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
2026         $ret = MWTimestamp::convert( $outputtype, $ts );
2027         if ( $ret === false ) {
2028                 wfDebug( "wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n" );
2029         }
2030         return $ret;
2031 }
2032
2033 /**
2034  * Return a formatted timestamp, or null if input is null.
2035  * For dealing with nullable timestamp columns in the database.
2036  *
2037  * @param int $outputtype
2038  * @param string $ts
2039  * @return string
2040  */
2041 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2042         if ( is_null( $ts ) ) {
2043                 return null;
2044         } else {
2045                 return wfTimestamp( $outputtype, $ts );
2046         }
2047 }
2048
2049 /**
2050  * Convenience function; returns MediaWiki timestamp for the present time.
2051  *
2052  * @return string
2053  */
2054 function wfTimestampNow() {
2055         # return NOW
2056         return MWTimestamp::now( TS_MW );
2057 }
2058
2059 /**
2060  * Check if the operating system is Windows
2061  *
2062  * @return bool True if it's Windows, false otherwise.
2063  */
2064 function wfIsWindows() {
2065         static $isWindows = null;
2066         if ( $isWindows === null ) {
2067                 $isWindows = strtoupper( substr( PHP_OS, 0, 3 ) ) === 'WIN';
2068         }
2069         return $isWindows;
2070 }
2071
2072 /**
2073  * Check if we are running under HHVM
2074  *
2075  * @return bool
2076  */
2077 function wfIsHHVM() {
2078         return defined( 'HHVM_VERSION' );
2079 }
2080
2081 /**
2082  * Tries to get the system directory for temporary files. First
2083  * $wgTmpDirectory is checked, and then the TMPDIR, TMP, and TEMP
2084  * environment variables are then checked in sequence, then
2085  * sys_get_temp_dir(), then upload_tmp_dir from php.ini.
2086  *
2087  * NOTE: When possible, use instead the tmpfile() function to create
2088  * temporary files to avoid race conditions on file creation, etc.
2089  *
2090  * @return string
2091  */
2092 function wfTempDir() {
2093         global $wgTmpDirectory;
2094
2095         if ( $wgTmpDirectory !== false ) {
2096                 return $wgTmpDirectory;
2097         }
2098
2099         return TempFSFile::getUsableTempDirectory();
2100 }
2101
2102 /**
2103  * Make directory, and make all parent directories if they don't exist
2104  *
2105  * @param string $dir Full path to directory to create
2106  * @param int $mode Chmod value to use, default is $wgDirectoryMode
2107  * @param string $caller Optional caller param for debugging.
2108  * @throws MWException
2109  * @return bool
2110  */
2111 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2112         global $wgDirectoryMode;
2113
2114         if ( FileBackend::isStoragePath( $dir ) ) { // sanity
2115                 throw new MWException( __FUNCTION__ . " given storage path '$dir'." );
2116         }
2117
2118         if ( !is_null( $caller ) ) {
2119                 wfDebug( "$caller: called wfMkdirParents($dir)\n" );
2120         }
2121
2122         if ( strval( $dir ) === '' || is_dir( $dir ) ) {
2123                 return true;
2124         }
2125
2126         $dir = str_replace( [ '\\', '/' ], DIRECTORY_SEPARATOR, $dir );
2127
2128         if ( is_null( $mode ) ) {
2129                 $mode = $wgDirectoryMode;
2130         }
2131
2132         // Turn off the normal warning, we're doing our own below
2133         MediaWiki\suppressWarnings();
2134         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2135         MediaWiki\restoreWarnings();
2136
2137         if ( !$ok ) {
2138                 // directory may have been created on another request since we last checked
2139                 if ( is_dir( $dir ) ) {
2140                         return true;
2141                 }
2142
2143                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2144                 wfLogWarning( sprintf( "failed to mkdir \"%s\" mode 0%o", $dir, $mode ) );
2145         }
2146         return $ok;
2147 }
2148
2149 /**
2150  * Remove a directory and all its content.
2151  * Does not hide error.
2152  * @param string $dir
2153  */
2154 function wfRecursiveRemoveDir( $dir ) {
2155         wfDebug( __FUNCTION__ . "( $dir )\n" );
2156         // taken from https://secure.php.net/manual/en/function.rmdir.php#98622
2157         if ( is_dir( $dir ) ) {
2158                 $objects = scandir( $dir );
2159                 foreach ( $objects as $object ) {
2160                         if ( $object != "." && $object != ".." ) {
2161                                 if ( filetype( $dir . '/' . $object ) == "dir" ) {
2162                                         wfRecursiveRemoveDir( $dir . '/' . $object );
2163                                 } else {
2164                                         unlink( $dir . '/' . $object );
2165                                 }
2166                         }
2167                 }
2168                 reset( $objects );
2169                 rmdir( $dir );
2170         }
2171 }
2172
2173 /**
2174  * @param int $nr The number to format
2175  * @param int $acc The number of digits after the decimal point, default 2
2176  * @param bool $round Whether or not to round the value, default true
2177  * @return string
2178  */
2179 function wfPercent( $nr, $acc = 2, $round = true ) {
2180         $ret = sprintf( "%.${acc}f", $nr );
2181         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2182 }
2183
2184 /**
2185  * Safety wrapper around ini_get() for boolean settings.
2186  * The values returned from ini_get() are pre-normalized for settings
2187  * set via php.ini or php_flag/php_admin_flag... but *not*
2188  * for those set via php_value/php_admin_value.
2189  *
2190  * It's fairly common for people to use php_value instead of php_flag,
2191  * which can leave you with an 'off' setting giving a false positive
2192  * for code that just takes the ini_get() return value as a boolean.
2193  *
2194  * To make things extra interesting, setting via php_value accepts
2195  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2196  * Unrecognized values go false... again opposite PHP's own coercion
2197  * from string to bool.
2198  *
2199  * Luckily, 'properly' set settings will always come back as '0' or '1',
2200  * so we only have to worry about them and the 'improper' settings.
2201  *
2202  * I frickin' hate PHP... :P
2203  *
2204  * @param string $setting
2205  * @return bool
2206  */
2207 function wfIniGetBool( $setting ) {
2208         $val = strtolower( ini_get( $setting ) );
2209         // 'on' and 'true' can't have whitespace around them, but '1' can.
2210         return $val == 'on'
2211                 || $val == 'true'
2212                 || $val == 'yes'
2213                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2214 }
2215
2216 /**
2217  * Version of escapeshellarg() that works better on Windows.
2218  *
2219  * Originally, this fixed the incorrect use of single quotes on Windows
2220  * (https://bugs.php.net/bug.php?id=26285) and the locale problems on Linux in
2221  * PHP 5.2.6+ (bug backported to earlier distro releases of PHP).
2222  *
2223  * @param string ... strings to escape and glue together, or a single array of strings parameter
2224  * @return string
2225  */
2226 function wfEscapeShellArg( /*...*/ ) {
2227         $args = func_get_args();
2228         if ( count( $args ) === 1 && is_array( reset( $args ) ) ) {
2229                 // If only one argument has been passed, and that argument is an array,
2230                 // treat it as a list of arguments
2231                 $args = reset( $args );
2232         }
2233
2234         $first = true;
2235         $retVal = '';
2236         foreach ( $args as $arg ) {
2237                 if ( !$first ) {
2238                         $retVal .= ' ';
2239                 } else {
2240                         $first = false;
2241                 }
2242
2243                 if ( wfIsWindows() ) {
2244                         // Escaping for an MSVC-style command line parser and CMD.EXE
2245                         // @codingStandardsIgnoreStart For long URLs
2246                         // Refs:
2247                         //  * https://web.archive.org/web/20020708081031/http://mailman.lyra.org/pipermail/scite-interest/2002-March/000436.html
2248                         //  * https://technet.microsoft.com/en-us/library/cc723564.aspx
2249                         //  * T15518
2250                         //  * CR r63214
2251                         // Double the backslashes before any double quotes. Escape the double quotes.
2252                         // @codingStandardsIgnoreEnd
2253                         $tokens = preg_split( '/(\\\\*")/', $arg, -1, PREG_SPLIT_DELIM_CAPTURE );
2254                         $arg = '';
2255                         $iteration = 0;
2256                         foreach ( $tokens as $token ) {
2257                                 if ( $iteration % 2 == 1 ) {
2258                                         // Delimiter, a double quote preceded by zero or more slashes
2259                                         $arg .= str_replace( '\\', '\\\\', substr( $token, 0, -1 ) ) . '\\"';
2260                                 } elseif ( $iteration % 4 == 2 ) {
2261                                         // ^ in $token will be outside quotes, need to be escaped
2262                                         $arg .= str_replace( '^', '^^', $token );
2263                                 } else { // $iteration % 4 == 0
2264                                         // ^ in $token will appear inside double quotes, so leave as is
2265                                         $arg .= $token;
2266                                 }
2267                                 $iteration++;
2268                         }
2269                         // Double the backslashes before the end of the string, because
2270                         // we will soon add a quote
2271                         $m = [];
2272                         if ( preg_match( '/^(.*?)(\\\\+)$/', $arg, $m ) ) {
2273                                 $arg = $m[1] . str_replace( '\\', '\\\\', $m[2] );
2274                         }
2275
2276                         // Add surrounding quotes
2277                         $retVal .= '"' . $arg . '"';
2278                 } else {
2279                         $retVal .= escapeshellarg( $arg );
2280                 }
2281         }
2282         return $retVal;
2283 }
2284
2285 /**
2286  * Check if wfShellExec() is effectively disabled via php.ini config
2287  *
2288  * @return bool|string False or 'disabled'
2289  * @since 1.22
2290  */
2291 function wfShellExecDisabled() {
2292         static $disabled = null;
2293         if ( is_null( $disabled ) ) {
2294                 if ( !function_exists( 'proc_open' ) ) {
2295                         wfDebug( "proc_open() is disabled\n" );
2296                         $disabled = 'disabled';
2297                 } else {
2298                         $disabled = false;
2299                 }
2300         }
2301         return $disabled;
2302 }
2303
2304 /**
2305  * Execute a shell command, with time and memory limits mirrored from the PHP
2306  * configuration if supported.
2307  *
2308  * @param string|string[] $cmd If string, a properly shell-escaped command line,
2309  *   or an array of unescaped arguments, in which case each value will be escaped
2310  *   Example:   [ 'convert', '-font', 'font name' ] would produce "'convert' '-font' 'font name'"
2311  * @param null|mixed &$retval Optional, will receive the program's exit code.
2312  *   (non-zero is usually failure). If there is an error from
2313  *   read, select, or proc_open(), this will be set to -1.
2314  * @param array $environ Optional environment variables which should be
2315  *   added to the executed command environment.
2316  * @param array $limits Optional array with limits(filesize, memory, time, walltime)
2317  *   this overwrites the global wgMaxShell* limits.
2318  * @param array $options Array of options:
2319  *   - duplicateStderr: Set this to true to duplicate stderr to stdout,
2320  *     including errors from limit.sh
2321  *   - profileMethod: By default this function will profile based on the calling
2322  *     method. Set this to a string for an alternative method to profile from
2323  *
2324  * @return string Collected stdout as a string
2325  */
2326 function wfShellExec( $cmd, &$retval = null, $environ = [],
2327         $limits = [], $options = []
2328 ) {
2329         global $IP, $wgMaxShellMemory, $wgMaxShellFileSize, $wgMaxShellTime,
2330                 $wgMaxShellWallClockTime, $wgShellCgroup;
2331
2332         $disabled = wfShellExecDisabled();
2333         if ( $disabled ) {
2334                 $retval = 1;
2335                 return 'Unable to run external programs, proc_open() is disabled.';
2336         }
2337
2338         $includeStderr = isset( $options['duplicateStderr'] ) && $options['duplicateStderr'];
2339         $profileMethod = isset( $options['profileMethod'] ) ? $options['profileMethod'] : wfGetCaller();
2340
2341         $envcmd = '';
2342         foreach ( $environ as $k => $v ) {
2343                 if ( wfIsWindows() ) {
2344                         /* Surrounding a set in quotes (method used by wfEscapeShellArg) makes the quotes themselves
2345                          * appear in the environment variable, so we must use carat escaping as documented in
2346                          * https://technet.microsoft.com/en-us/library/cc723564.aspx
2347                          * Note however that the quote isn't listed there, but is needed, and the parentheses
2348                          * are listed there but doesn't appear to need it.
2349                          */
2350                         $envcmd .= "set $k=" . preg_replace( '/([&|()<>^"])/', '^\\1', $v ) . '&& ';
2351                 } else {
2352                         /* Assume this is a POSIX shell, thus required to accept variable assignments before the command
2353                          * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_09_01
2354                          */
2355                         $envcmd .= "$k=" . escapeshellarg( $v ) . ' ';
2356                 }
2357         }
2358         if ( is_array( $cmd ) ) {
2359                 $cmd = wfEscapeShellArg( $cmd );
2360         }
2361
2362         $cmd = $envcmd . $cmd;
2363
2364         $useLogPipe = false;
2365         if ( is_executable( '/bin/bash' ) ) {
2366                 $time = intval( isset( $limits['time'] ) ? $limits['time'] : $wgMaxShellTime );
2367                 if ( isset( $limits['walltime'] ) ) {
2368                         $wallTime = intval( $limits['walltime'] );
2369                 } elseif ( isset( $limits['time'] ) ) {
2370                         $wallTime = $time;
2371                 } else {
2372                         $wallTime = intval( $wgMaxShellWallClockTime );
2373                 }
2374                 $mem = intval( isset( $limits['memory'] ) ? $limits['memory'] : $wgMaxShellMemory );
2375                 $filesize = intval( isset( $limits['filesize'] ) ? $limits['filesize'] : $wgMaxShellFileSize );
2376
2377                 if ( $time > 0 || $mem > 0 || $filesize > 0 || $wallTime > 0 ) {
2378                         $cmd = '/bin/bash ' . escapeshellarg( "$IP/includes/limit.sh" ) . ' ' .
2379                                 escapeshellarg( $cmd ) . ' ' .
2380                                 escapeshellarg(
2381                                         "MW_INCLUDE_STDERR=" . ( $includeStderr ? '1' : '' ) . ';' .
2382                                         "MW_CPU_LIMIT=$time; " .
2383                                         'MW_CGROUP=' . escapeshellarg( $wgShellCgroup ) . '; ' .
2384                                         "MW_MEM_LIMIT=$mem; " .
2385                                         "MW_FILE_SIZE_LIMIT=$filesize; " .
2386                                         "MW_WALL_CLOCK_LIMIT=$wallTime; " .
2387                                         "MW_USE_LOG_PIPE=yes"
2388                                 );
2389                         $useLogPipe = true;
2390                 } elseif ( $includeStderr ) {
2391                         $cmd .= ' 2>&1';
2392                 }
2393         } elseif ( $includeStderr ) {
2394                 $cmd .= ' 2>&1';
2395         }
2396         wfDebug( "wfShellExec: $cmd\n" );
2397
2398         // Don't try to execute commands that exceed Linux's MAX_ARG_STRLEN.
2399         // Other platforms may be more accomodating, but we don't want to be
2400         // accomodating, because very long commands probably include user
2401         // input. See T129506.
2402         if ( strlen( $cmd ) > SHELL_MAX_ARG_STRLEN ) {
2403                 throw new Exception( __METHOD__ .
2404                         '(): total length of $cmd must not exceed SHELL_MAX_ARG_STRLEN' );
2405         }
2406
2407         $desc = [
2408                 0 => [ 'file', 'php://stdin', 'r' ],
2409                 1 => [ 'pipe', 'w' ],
2410                 2 => [ 'file', 'php://stderr', 'w' ] ];
2411         if ( $useLogPipe ) {
2412                 $desc[3] = [ 'pipe', 'w' ];
2413         }
2414         $pipes = null;
2415         $scoped = Profiler::instance()->scopedProfileIn( __FUNCTION__ . '-' . $profileMethod );
2416         $proc = proc_open( $cmd, $desc, $pipes );
2417         if ( !$proc ) {
2418                 wfDebugLog( 'exec', "proc_open() failed: $cmd" );
2419                 $retval = -1;
2420                 return '';
2421         }
2422         $outBuffer = $logBuffer = '';
2423         $emptyArray = [];
2424         $status = false;
2425         $logMsg = false;
2426
2427         /* According to the documentation, it is possible for stream_select()
2428          * to fail due to EINTR. I haven't managed to induce this in testing
2429          * despite sending various signals. If it did happen, the error
2430          * message would take the form:
2431          *
2432          * stream_select(): unable to select [4]: Interrupted system call (max_fd=5)
2433          *
2434          * where [4] is the value of the macro EINTR and "Interrupted system
2435          * call" is string which according to the Linux manual is "possibly"
2436          * localised according to LC_MESSAGES.
2437          */
2438         $eintr = defined( 'SOCKET_EINTR' ) ? SOCKET_EINTR : 4;
2439         $eintrMessage = "stream_select(): unable to select [$eintr]";
2440
2441         $running = true;
2442         $timeout = null;
2443         $numReadyPipes = 0;
2444
2445         while ( $running === true || $numReadyPipes !== 0 ) {
2446                 if ( $running ) {
2447                         $status = proc_get_status( $proc );
2448                         // If the process has terminated, switch to nonblocking selects
2449                         // for getting any data still waiting to be read.
2450                         if ( !$status['running'] ) {
2451                                 $running = false;
2452                                 $timeout = 0;
2453                         }
2454                 }
2455
2456                 $readyPipes = $pipes;
2457
2458                 // Clear last error
2459                 // @codingStandardsIgnoreStart Generic.PHP.NoSilencedErrors.Discouraged
2460                 @trigger_error( '' );
2461                 $numReadyPipes = @stream_select( $readyPipes, $emptyArray, $emptyArray, $timeout );
2462                 if ( $numReadyPipes === false ) {
2463                         // @codingStandardsIgnoreEnd
2464                         $error = error_get_last();
2465                         if ( strncmp( $error['message'], $eintrMessage, strlen( $eintrMessage ) ) == 0 ) {
2466                                 continue;
2467                         } else {
2468                                 trigger_error( $error['message'], E_USER_WARNING );
2469                                 $logMsg = $error['message'];
2470                                 break;
2471                         }
2472                 }
2473                 foreach ( $readyPipes as $fd => $pipe ) {
2474                         $block = fread( $pipe, 65536 );
2475                         if ( $block === '' ) {
2476                                 // End of file
2477                                 fclose( $pipes[$fd] );
2478                                 unset( $pipes[$fd] );
2479                                 if ( !$pipes ) {
2480                                         break 2;
2481                                 }
2482                         } elseif ( $block === false ) {
2483                                 // Read error
2484                                 $logMsg = "Error reading from pipe";
2485                                 break 2;
2486                         } elseif ( $fd == 1 ) {
2487                                 // From stdout
2488                                 $outBuffer .= $block;
2489                         } elseif ( $fd == 3 ) {
2490                                 // From log FD
2491                                 $logBuffer .= $block;
2492                                 if ( strpos( $block, "\n" ) !== false ) {
2493                                         $lines = explode( "\n", $logBuffer );
2494                                         $logBuffer = array_pop( $lines );
2495                                         foreach ( $lines as $line ) {
2496                                                 wfDebugLog( 'exec', $line );
2497                                         }
2498                                 }
2499                         }
2500                 }
2501         }
2502
2503         foreach ( $pipes as $pipe ) {
2504                 fclose( $pipe );
2505         }
2506
2507         // Use the status previously collected if possible, since proc_get_status()
2508         // just calls waitpid() which will not return anything useful the second time.
2509         if ( $running ) {
2510                 $status = proc_get_status( $proc );
2511         }
2512
2513         if ( $logMsg !== false ) {
2514                 // Read/select error
2515                 $retval = -1;
2516                 proc_close( $proc );
2517         } elseif ( $status['signaled'] ) {
2518                 $logMsg = "Exited with signal {$status['termsig']}";
2519                 $retval = 128 + $status['termsig'];
2520                 proc_close( $proc );
2521         } else {
2522                 if ( $status['running'] ) {
2523                         $retval = proc_close( $proc );
2524                 } else {
2525                         $retval = $status['exitcode'];
2526                         proc_close( $proc );
2527                 }
2528                 if ( $retval == 127 ) {
2529                         $logMsg = "Possibly missing executable file";
2530                 } elseif ( $retval >= 129 && $retval <= 192 ) {
2531                         $logMsg = "Probably exited with signal " . ( $retval - 128 );
2532                 }
2533         }
2534
2535         if ( $logMsg !== false ) {
2536                 wfDebugLog( 'exec', "$logMsg: $cmd" );
2537         }
2538
2539         return $outBuffer;
2540 }
2541
2542 /**
2543  * Execute a shell command, returning both stdout and stderr. Convenience
2544  * function, as all the arguments to wfShellExec can become unwieldy.
2545  *
2546  * @note This also includes errors from limit.sh, e.g. if $wgMaxShellFileSize is exceeded.
2547  * @param string|string[] $cmd If string, a properly shell-escaped command line,
2548  *   or an array of unescaped arguments, in which case each value will be escaped
2549  *   Example:   [ 'convert', '-font', 'font name' ] would produce "'convert' '-font' 'font name'"
2550  * @param null|mixed &$retval Optional, will receive the program's exit code.
2551  *   (non-zero is usually failure)
2552  * @param array $environ Optional environment variables which should be
2553  *   added to the executed command environment.
2554  * @param array $limits Optional array with limits(filesize, memory, time, walltime)
2555  *   this overwrites the global wgMaxShell* limits.
2556  * @return string Collected stdout and stderr as a string
2557  */
2558 function wfShellExecWithStderr( $cmd, &$retval = null, $environ = [], $limits = [] ) {
2559         return wfShellExec( $cmd, $retval, $environ, $limits,
2560                 [ 'duplicateStderr' => true, 'profileMethod' => wfGetCaller() ] );
2561 }
2562
2563 /**
2564  * Formerly set the locale for locale-sensitive operations
2565  *
2566  * This is now done in Setup.php.
2567  *
2568  * @deprecated since 1.30, no longer needed
2569  * @see $wgShellLocale
2570  */
2571 function wfInitShellLocale() {
2572 }
2573
2574 /**
2575  * Generate a shell-escaped command line string to run a MediaWiki cli script.
2576  * Note that $parameters should be a flat array and an option with an argument
2577  * should consist of two consecutive items in the array (do not use "--option value").
2578  *
2579  * @param string $script MediaWiki cli script path
2580  * @param array $parameters Arguments and options to the script
2581  * @param array $options Associative array of options:
2582  *     'php': The path to the php executable
2583  *     'wrapper': Path to a PHP wrapper to handle the maintenance script
2584  * @return string
2585  */
2586 function wfShellWikiCmd( $script, array $parameters = [], array $options = [] ) {
2587         global $wgPhpCli;
2588         // Give site config file a chance to run the script in a wrapper.
2589         // The caller may likely want to call wfBasename() on $script.
2590         Hooks::run( 'wfShellWikiCmd', [ &$script, &$parameters, &$options ] );
2591         $cmd = isset( $options['php'] ) ? [ $options['php'] ] : [ $wgPhpCli ];
2592         if ( isset( $options['wrapper'] ) ) {
2593                 $cmd[] = $options['wrapper'];
2594         }
2595         $cmd[] = $script;
2596         // Escape each parameter for shell
2597         return wfEscapeShellArg( array_merge( $cmd, $parameters ) );
2598 }
2599
2600 /**
2601  * wfMerge attempts to merge differences between three texts.
2602  * Returns true for a clean merge and false for failure or a conflict.
2603  *
2604  * @param string $old
2605  * @param string $mine
2606  * @param string $yours
2607  * @param string $result
2608  * @return bool
2609  */
2610 function wfMerge( $old, $mine, $yours, &$result ) {
2611         global $wgDiff3;
2612
2613         # This check may also protect against code injection in
2614         # case of broken installations.
2615         MediaWiki\suppressWarnings();
2616         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
2617         MediaWiki\restoreWarnings();
2618
2619         if ( !$haveDiff3 ) {
2620                 wfDebug( "diff3 not found\n" );
2621                 return false;
2622         }
2623
2624         # Make temporary files
2625         $td = wfTempDir();
2626         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
2627         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
2628         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
2629
2630         # NOTE: diff3 issues a warning to stderr if any of the files does not end with
2631         #       a newline character. To avoid this, we normalize the trailing whitespace before
2632         #       creating the diff.
2633
2634         fwrite( $oldtextFile, rtrim( $old ) . "\n" );
2635         fclose( $oldtextFile );
2636         fwrite( $mytextFile, rtrim( $mine ) . "\n" );
2637         fclose( $mytextFile );
2638         fwrite( $yourtextFile, rtrim( $yours ) . "\n" );
2639         fclose( $yourtextFile );
2640
2641         # Check for a conflict
2642         $cmd = wfEscapeShellArg( $wgDiff3, '-a', '--overlap-only', $mytextName,
2643                 $oldtextName, $yourtextName );
2644         $handle = popen( $cmd, 'r' );
2645
2646         if ( fgets( $handle, 1024 ) ) {
2647                 $conflict = true;
2648         } else {
2649                 $conflict = false;
2650         }
2651         pclose( $handle );
2652
2653         # Merge differences
2654         $cmd = wfEscapeShellArg( $wgDiff3, '-a', '-e', '--merge', $mytextName,
2655                 $oldtextName, $yourtextName );
2656         $handle = popen( $cmd, 'r' );
2657         $result = '';
2658         do {
2659                 $data = fread( $handle, 8192 );
2660                 if ( strlen( $data ) == 0 ) {
2661                         break;
2662                 }
2663                 $result .= $data;
2664         } while ( true );
2665         pclose( $handle );
2666         unlink( $mytextName );
2667         unlink( $oldtextName );
2668         unlink( $yourtextName );
2669
2670         if ( $result === '' && $old !== '' && !$conflict ) {
2671                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
2672                 $conflict = true;
2673         }
2674         return !$conflict;
2675 }
2676
2677 /**
2678  * Returns unified plain-text diff of two texts.
2679  * "Useful" for machine processing of diffs.
2680  *
2681  * @deprecated since 1.25, use DiffEngine/UnifiedDiffFormatter directly
2682  *
2683  * @param string $before The text before the changes.
2684  * @param string $after The text after the changes.
2685  * @param string $params Command-line options for the diff command.
2686  * @return string Unified diff of $before and $after
2687  */
2688 function wfDiff( $before, $after, $params = '-u' ) {
2689         if ( $before == $after ) {
2690                 return '';
2691         }
2692
2693         global $wgDiff;
2694         MediaWiki\suppressWarnings();
2695         $haveDiff = $wgDiff && file_exists( $wgDiff );
2696         MediaWiki\restoreWarnings();
2697
2698         # This check may also protect against code injection in
2699         # case of broken installations.
2700         if ( !$haveDiff ) {
2701                 wfDebug( "diff executable not found\n" );
2702                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
2703                 $format = new UnifiedDiffFormatter();
2704                 return $format->format( $diffs );
2705         }
2706
2707         # Make temporary files
2708         $td = wfTempDir();
2709         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
2710         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
2711
2712         fwrite( $oldtextFile, $before );
2713         fclose( $oldtextFile );
2714         fwrite( $newtextFile, $after );
2715         fclose( $newtextFile );
2716
2717         // Get the diff of the two files
2718         $cmd = "$wgDiff " . $params . ' ' . wfEscapeShellArg( $oldtextName, $newtextName );
2719
2720         $h = popen( $cmd, 'r' );
2721         if ( !$h ) {
2722                 unlink( $oldtextName );
2723                 unlink( $newtextName );
2724                 throw new Exception( __METHOD__ . '(): popen() failed' );
2725         }
2726
2727         $diff = '';
2728
2729         do {
2730                 $data = fread( $h, 8192 );
2731                 if ( strlen( $data ) == 0 ) {
2732                         break;
2733                 }
2734                 $diff .= $data;
2735         } while ( true );
2736
2737         // Clean up
2738         pclose( $h );
2739         unlink( $oldtextName );
2740         unlink( $newtextName );
2741
2742         // Kill the --- and +++ lines. They're not useful.
2743         $diff_lines = explode( "\n", $diff );
2744         if ( isset( $diff_lines[0] ) && strpos( $diff_lines[0], '---' ) === 0 ) {
2745                 unset( $diff_lines[0] );
2746         }
2747         if ( isset( $diff_lines[1] ) && strpos( $diff_lines[1], '+++' ) === 0 ) {
2748                 unset( $diff_lines[1] );
2749         }
2750
2751         $diff = implode( "\n", $diff_lines );
2752
2753         return $diff;
2754 }
2755
2756 /**
2757  * This function works like "use VERSION" in Perl, the program will die with a
2758  * backtrace if the current version of PHP is less than the version provided
2759  *
2760  * This is useful for extensions which due to their nature are not kept in sync
2761  * with releases, and might depend on other versions of PHP than the main code
2762  *
2763  * Note: PHP might die due to parsing errors in some cases before it ever
2764  *       manages to call this function, such is life
2765  *
2766  * @see perldoc -f use
2767  *
2768  * @param string|int|float $req_ver The version to check, can be a string, an integer, or a float
2769  * @throws MWException
2770  */
2771 function wfUsePHP( $req_ver ) {
2772         $php_ver = PHP_VERSION;
2773
2774         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
2775                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
2776         }
2777 }
2778
2779 /**
2780  * This function works like "use VERSION" in Perl except it checks the version
2781  * of MediaWiki, the program will die with a backtrace if the current version
2782  * of MediaWiki is less than the version provided.
2783  *
2784  * This is useful for extensions which due to their nature are not kept in sync
2785  * with releases
2786  *
2787  * Note: Due to the behavior of PHP's version_compare() which is used in this
2788  * function, if you want to allow the 'wmf' development versions add a 'c' (or
2789  * any single letter other than 'a', 'b' or 'p') as a post-fix to your
2790  * targeted version number. For example if you wanted to allow any variation
2791  * of 1.22 use `wfUseMW( '1.22c' )`. Using an 'a' or 'b' instead of 'c' will
2792  * not result in the same comparison due to the internal logic of
2793  * version_compare().
2794  *
2795  * @see perldoc -f use
2796  *
2797  * @deprecated since 1.26, use the "requires' property of extension.json
2798  * @param string|int|float $req_ver The version to check, can be a string, an integer, or a float
2799  * @throws MWException
2800  */
2801 function wfUseMW( $req_ver ) {
2802         global $wgVersion;
2803
2804         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
2805                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
2806         }
2807 }
2808
2809 /**
2810  * Return the final portion of a pathname.
2811  * Reimplemented because PHP5's "basename()" is buggy with multibyte text.
2812  * https://bugs.php.net/bug.php?id=33898
2813  *
2814  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
2815  * We'll consider it so always, as we don't want '\s' in our Unix paths either.
2816  *
2817  * @param string $path
2818  * @param string $suffix String to remove if present
2819  * @return string
2820  */
2821 function wfBaseName( $path, $suffix = '' ) {
2822         if ( $suffix == '' ) {
2823                 $encSuffix = '';
2824         } else {
2825                 $encSuffix = '(?:' . preg_quote( $suffix, '#' ) . ')?';
2826         }
2827
2828         $matches = [];
2829         if ( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2830                 return $matches[1];
2831         } else {
2832                 return '';
2833         }
2834 }
2835
2836 /**
2837  * Generate a relative path name to the given file.
2838  * May explode on non-matching case-insensitive paths,
2839  * funky symlinks, etc.
2840  *
2841  * @param string $path Absolute destination path including target filename
2842  * @param string $from Absolute source path, directory only
2843  * @return string
2844  */
2845 function wfRelativePath( $path, $from ) {
2846         // Normalize mixed input on Windows...
2847         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2848         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2849
2850         // Trim trailing slashes -- fix for drive root
2851         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2852         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2853
2854         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2855         $against = explode( DIRECTORY_SEPARATOR, $from );
2856
2857         if ( $pieces[0] !== $against[0] ) {
2858                 // Non-matching Windows drive letters?
2859                 // Return a full path.
2860                 return $path;
2861         }
2862
2863         // Trim off common prefix
2864         while ( count( $pieces ) && count( $against )
2865                 && $pieces[0] == $against[0] ) {
2866                 array_shift( $pieces );
2867                 array_shift( $against );
2868         }
2869
2870         // relative dots to bump us to the parent
2871         while ( count( $against ) ) {
2872                 array_unshift( $pieces, '..' );
2873                 array_shift( $against );
2874         }
2875
2876         array_push( $pieces, wfBaseName( $path ) );
2877
2878         return implode( DIRECTORY_SEPARATOR, $pieces );
2879 }
2880
2881 /**
2882  * Convert an arbitrarily-long digit string from one numeric base
2883  * to another, optionally zero-padding to a minimum column width.
2884  *
2885  * Supports base 2 through 36; digit values 10-36 are represented
2886  * as lowercase letters a-z. Input is case-insensitive.
2887  *
2888  * @deprecated since 1.27 Use Wikimedia\base_convert() directly
2889  *
2890  * @param string $input Input number
2891  * @param int $sourceBase Base of the input number
2892  * @param int $destBase Desired base of the output
2893  * @param int $pad Minimum number of digits in the output (pad with zeroes)
2894  * @param bool $lowercase Whether to output in lowercase or uppercase
2895  * @param string $engine Either "gmp", "bcmath", or "php"
2896  * @return string|bool The output number as a string, or false on error
2897  */
2898 function wfBaseConvert( $input, $sourceBase, $destBase, $pad = 1,
2899         $lowercase = true, $engine = 'auto'
2900 ) {
2901         return Wikimedia\base_convert( $input, $sourceBase, $destBase, $pad, $lowercase, $engine );
2902 }
2903
2904 /**
2905  * @deprecated since 1.27, PHP's session generation isn't used with
2906  *  MediaWiki\Session\SessionManager
2907  */
2908 function wfFixSessionID() {
2909         wfDeprecated( __FUNCTION__, '1.27' );
2910 }
2911
2912 /**
2913  * Reset the session id
2914  *
2915  * @deprecated since 1.27, use MediaWiki\Session\SessionManager instead
2916  * @since 1.22
2917  */
2918 function wfResetSessionID() {
2919         wfDeprecated( __FUNCTION__, '1.27' );
2920         $session = SessionManager::getGlobalSession();
2921         $delay = $session->delaySave();
2922
2923         $session->resetId();
2924
2925         // Make sure a session is started, since that's what the old
2926         // wfResetSessionID() did.
2927         if ( session_id() !== $session->getId() ) {
2928                 wfSetupSession( $session->getId() );
2929         }
2930
2931         ScopedCallback::consume( $delay );
2932 }
2933
2934 /**
2935  * Initialise php session
2936  *
2937  * @deprecated since 1.27, use MediaWiki\Session\SessionManager instead.
2938  *  Generally, "using" SessionManager will be calling ->getSessionById() or
2939  *  ::getGlobalSession() (depending on whether you were passing $sessionId
2940  *  here), then calling $session->persist().
2941  * @param bool|string $sessionId
2942  */
2943 function wfSetupSession( $sessionId = false ) {
2944         wfDeprecated( __FUNCTION__, '1.27' );
2945
2946         if ( $sessionId ) {
2947                 session_id( $sessionId );
2948         }
2949
2950         $session = SessionManager::getGlobalSession();
2951         $session->persist();
2952
2953         if ( session_id() !== $session->getId() ) {
2954                 session_id( $session->getId() );
2955         }
2956         MediaWiki\quietCall( 'session_start' );
2957 }
2958
2959 /**
2960  * Get an object from the precompiled serialized directory
2961  *
2962  * @param string $name
2963  * @return mixed The variable on success, false on failure
2964  */
2965 function wfGetPrecompiledData( $name ) {
2966         global $IP;
2967
2968         $file = "$IP/serialized/$name";
2969         if ( file_exists( $file ) ) {
2970                 $blob = file_get_contents( $file );
2971                 if ( $blob ) {
2972                         return unserialize( $blob );
2973                 }
2974         }
2975         return false;
2976 }
2977
2978 /**
2979  * Make a cache key for the local wiki.
2980  *
2981  * @deprecated since 1.30 Call makeKey on a BagOStuff instance
2982  * @param string $args,...
2983  * @return string
2984  */
2985 function wfMemcKey( /*...*/ ) {
2986         return call_user_func_array(
2987                 [ ObjectCache::getLocalClusterInstance(), 'makeKey' ],
2988                 func_get_args()
2989         );
2990 }
2991
2992 /**
2993  * Make a cache key for a foreign DB.
2994  *
2995  * Must match what wfMemcKey() would produce in context of the foreign wiki.
2996  *
2997  * @param string $db
2998  * @param string $prefix
2999  * @param string $args,...
3000  * @return string
3001  */
3002 function wfForeignMemcKey( $db, $prefix /*...*/ ) {
3003         $args = array_slice( func_get_args(), 2 );
3004         $keyspace = $prefix ? "$db-$prefix" : $db;
3005         return call_user_func_array(
3006                 [ ObjectCache::getLocalClusterInstance(), 'makeKeyInternal' ],
3007                 [ $keyspace, $args ]
3008         );
3009 }
3010
3011 /**
3012  * Make a cache key with database-agnostic prefix.
3013  *
3014  * Doesn't have a wiki-specific namespace. Uses a generic 'global' prefix
3015  * instead. Must have a prefix as otherwise keys that use a database name
3016  * in the first segment will clash with wfMemcKey/wfForeignMemcKey.
3017  *
3018  * @deprecated since 1.30 Call makeGlobalKey on a BagOStuff instance
3019  * @since 1.26
3020  * @param string $args,...
3021  * @return string
3022  */
3023 function wfGlobalCacheKey( /*...*/ ) {
3024         return call_user_func_array(
3025                 [ ObjectCache::getLocalClusterInstance(), 'makeGlobalKey' ],
3026                 func_get_args()
3027         );
3028 }
3029
3030 /**
3031  * Get an ASCII string identifying this wiki
3032  * This is used as a prefix in memcached keys
3033  *
3034  * @return string
3035  */
3036 function wfWikiID() {
3037         global $wgDBprefix, $wgDBname;
3038         if ( $wgDBprefix ) {
3039                 return "$wgDBname-$wgDBprefix";
3040         } else {
3041                 return $wgDBname;
3042         }
3043 }
3044
3045 /**
3046  * Split a wiki ID into DB name and table prefix
3047  *
3048  * @param string $wiki
3049  *
3050  * @return array
3051  */
3052 function wfSplitWikiID( $wiki ) {
3053         $bits = explode( '-', $wiki, 2 );
3054         if ( count( $bits ) < 2 ) {
3055                 $bits[] = '';
3056         }
3057         return $bits;
3058 }
3059
3060 /**
3061  * Get a Database object.
3062  *
3063  * @param int $db Index of the connection to get. May be DB_MASTER for the
3064  *            master (for write queries), DB_REPLICA for potentially lagged read
3065  *            queries, or an integer >= 0 for a particular server.
3066  *
3067  * @param string|string[] $groups Query groups. An array of group names that this query
3068  *                belongs to. May contain a single string if the query is only
3069  *                in one group.
3070  *
3071  * @param string|bool $wiki The wiki ID, or false for the current wiki
3072  *
3073  * Note: multiple calls to wfGetDB(DB_REPLICA) during the course of one request
3074  * will always return the same object, unless the underlying connection or load
3075  * balancer is manually destroyed.
3076  *
3077  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
3078  * updater to ensure that a proper database is being updated.
3079  *
3080  * @todo Replace calls to wfGetDB with calls to LoadBalancer::getConnection()
3081  *       on an injected instance of LoadBalancer.
3082  *
3083  * @return \Wikimedia\Rdbms\Database
3084  */
3085 function wfGetDB( $db, $groups = [], $wiki = false ) {
3086         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
3087 }
3088
3089 /**
3090  * Get a load balancer object.
3091  *
3092  * @deprecated since 1.27, use MediaWikiServices::getDBLoadBalancer()
3093  *              or MediaWikiServices::getDBLoadBalancerFactory() instead.
3094  *
3095  * @param string|bool $wiki Wiki ID, or false for the current wiki
3096  * @return \Wikimedia\Rdbms\LoadBalancer
3097  */
3098 function wfGetLB( $wiki = false ) {
3099         if ( $wiki === false ) {
3100                 return MediaWikiServices::getInstance()->getDBLoadBalancer();
3101         } else {
3102                 $factory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
3103                 return $factory->getMainLB( $wiki );
3104         }
3105 }
3106
3107 /**
3108  * Get the load balancer factory object
3109  *
3110  * @deprecated since 1.27, use MediaWikiServices::getDBLoadBalancerFactory() instead.
3111  *
3112  * @return \Wikimedia\Rdbms\LBFactory
3113  */
3114 function wfGetLBFactory() {
3115         return MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
3116 }
3117
3118 /**
3119  * Find a file.
3120  * Shortcut for RepoGroup::singleton()->findFile()
3121  *
3122  * @param string $title String or Title object
3123  * @param array $options Associative array of options (see RepoGroup::findFile)
3124  * @return File|bool File, or false if the file does not exist
3125  */
3126 function wfFindFile( $title, $options = [] ) {
3127         return RepoGroup::singleton()->findFile( $title, $options );
3128 }
3129
3130 /**
3131  * Get an object referring to a locally registered file.
3132  * Returns a valid placeholder object if the file does not exist.
3133  *
3134  * @param Title|string $title
3135  * @return LocalFile|null A File, or null if passed an invalid Title
3136  */
3137 function wfLocalFile( $title ) {
3138         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
3139 }
3140
3141 /**
3142  * Should low-performance queries be disabled?
3143  *
3144  * @return bool
3145  * @codeCoverageIgnore
3146  */
3147 function wfQueriesMustScale() {
3148         global $wgMiserMode;
3149         return $wgMiserMode
3150                 || ( SiteStats::pages() > 100000
3151                 && SiteStats::edits() > 1000000
3152                 && SiteStats::users() > 10000 );
3153 }
3154
3155 /**
3156  * Get the path to a specified script file, respecting file
3157  * extensions; this is a wrapper around $wgScriptPath etc.
3158  * except for 'index' and 'load' which use $wgScript/$wgLoadScript
3159  *
3160  * @param string $script Script filename, sans extension
3161  * @return string
3162  */
3163 function wfScript( $script = 'index' ) {
3164         global $wgScriptPath, $wgScript, $wgLoadScript;
3165         if ( $script === 'index' ) {
3166                 return $wgScript;
3167         } elseif ( $script === 'load' ) {
3168                 return $wgLoadScript;
3169         } else {
3170                 return "{$wgScriptPath}/{$script}.php";
3171         }
3172 }
3173
3174 /**
3175  * Get the script URL.
3176  *
3177  * @return string Script URL
3178  */
3179 function wfGetScriptUrl() {
3180         if ( isset( $_SERVER['SCRIPT_NAME'] ) ) {
3181                 /* as it was called, minus the query string.
3182                  *
3183                  * Some sites use Apache rewrite rules to handle subdomains,
3184                  * and have PHP set up in a weird way that causes PHP_SELF
3185                  * to contain the rewritten URL instead of the one that the
3186                  * outside world sees.
3187                  *
3188                  * If in this mode, use SCRIPT_URL instead, which mod_rewrite
3189                  * provides containing the "before" URL.
3190                  */
3191                 return $_SERVER['SCRIPT_NAME'];
3192         } else {
3193                 return $_SERVER['URL'];
3194         }
3195 }
3196
3197 /**
3198  * Convenience function converts boolean values into "true"
3199  * or "false" (string) values
3200  *
3201  * @param bool $value
3202  * @return string
3203  */
3204 function wfBoolToStr( $value ) {
3205         return $value ? 'true' : 'false';
3206 }
3207
3208 /**
3209  * Get a platform-independent path to the null file, e.g. /dev/null
3210  *
3211  * @return string
3212  */
3213 function wfGetNull() {
3214         return wfIsWindows() ? 'NUL' : '/dev/null';
3215 }
3216
3217 /**
3218  * Waits for the replica DBs to catch up to the master position
3219  *
3220  * Use this when updating very large numbers of rows, as in maintenance scripts,
3221  * to avoid causing too much lag. Of course, this is a no-op if there are no replica DBs.
3222  *
3223  * By default this waits on the main DB cluster of the current wiki.
3224  * If $cluster is set to "*" it will wait on all DB clusters, including
3225  * external ones. If the lag being waiting on is caused by the code that
3226  * does this check, it makes since to use $ifWritesSince, particularly if
3227  * cluster is "*", to avoid excess overhead.
3228  *
3229  * Never call this function after a big DB write that is still in a transaction.
3230  * This only makes sense after the possible lag inducing changes were committed.
3231  *
3232  * @param float|null $ifWritesSince Only wait if writes were done since this UNIX timestamp
3233  * @param string|bool $wiki Wiki identifier accepted by wfGetLB
3234  * @param string|bool $cluster Cluster name accepted by LBFactory. Default: false.
3235  * @param int|null $timeout Max wait time. Default: 1 day (cli), ~10 seconds (web)
3236  * @return bool Success (able to connect and no timeouts reached)
3237  * @deprecated since 1.27 Use LBFactory::waitForReplication
3238  */
3239 function wfWaitForSlaves(
3240         $ifWritesSince = null, $wiki = false, $cluster = false, $timeout = null
3241 ) {
3242         if ( $timeout === null ) {
3243                 $timeout = ( PHP_SAPI === 'cli' ) ? 86400 : 10;
3244         }
3245
3246         if ( $cluster === '*' ) {
3247                 $cluster = false;
3248                 $wiki = false;
3249         } elseif ( $wiki === false ) {
3250                 $wiki = wfWikiID();
3251         }
3252
3253         try {
3254                 wfGetLBFactory()->waitForReplication( [
3255                         'wiki' => $wiki,
3256                         'cluster' => $cluster,
3257                         'timeout' => $timeout,
3258                         // B/C: first argument used to be "max seconds of lag"; ignore such values
3259                         'ifWritesSince' => ( $ifWritesSince > 1e9 ) ? $ifWritesSince : null
3260                 ] );
3261         } catch ( DBReplicationWaitError $e ) {
3262                 return false;
3263         }
3264
3265         return true;
3266 }
3267
3268 /**
3269  * Count down from $seconds to zero on the terminal, with a one-second pause
3270  * between showing each number. For use in command-line scripts.
3271  *
3272  * @codeCoverageIgnore
3273  * @param int $seconds
3274  */
3275 function wfCountDown( $seconds ) {
3276         for ( $i = $seconds; $i >= 0; $i-- ) {
3277                 if ( $i != $seconds ) {
3278                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3279                 }
3280                 echo $i;
3281                 flush();
3282                 if ( $i ) {
3283                         sleep( 1 );
3284                 }
3285         }
3286         echo "\n";
3287 }
3288
3289 /**
3290  * Replace all invalid characters with '-'.
3291  * Additional characters can be defined in $wgIllegalFileChars (see T22489).
3292  * By default, $wgIllegalFileChars includes ':', '/', '\'.
3293  *
3294  * @param string $name Filename to process
3295  * @return string
3296  */
3297 function wfStripIllegalFilenameChars( $name ) {
3298         global $wgIllegalFileChars;
3299         $illegalFileChars = $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '';
3300         $name = preg_replace(
3301                 "/[^" . Title::legalChars() . "]" . $illegalFileChars . "/",
3302                 '-',
3303                 $name
3304         );
3305         // $wgIllegalFileChars may not include '/' and '\', so we still need to do this
3306         $name = wfBaseName( $name );
3307         return $name;
3308 }
3309
3310 /**
3311  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit
3312  *
3313  * @return int Resulting value of the memory limit.
3314  */
3315 function wfMemoryLimit() {
3316         global $wgMemoryLimit;
3317         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3318         if ( $memlimit != -1 ) {
3319                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3320                 if ( $conflimit == -1 ) {
3321                         wfDebug( "Removing PHP's memory limit\n" );
3322                         MediaWiki\suppressWarnings();
3323                         ini_set( 'memory_limit', $conflimit );
3324                         MediaWiki\restoreWarnings();
3325                         return $conflimit;
3326                 } elseif ( $conflimit > $memlimit ) {
3327                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3328                         MediaWiki\suppressWarnings();
3329                         ini_set( 'memory_limit', $conflimit );
3330                         MediaWiki\restoreWarnings();
3331                         return $conflimit;
3332                 }
3333         }
3334         return $memlimit;
3335 }
3336
3337 /**
3338  * Set PHP's time limit to the larger of php.ini or $wgTransactionalTimeLimit
3339  *
3340  * @return int Prior time limit
3341  * @since 1.26
3342  */
3343 function wfTransactionalTimeLimit() {
3344         global $wgTransactionalTimeLimit;
3345
3346         $timeLimit = ini_get( 'max_execution_time' );
3347         // Note that CLI scripts use 0
3348         if ( $timeLimit > 0 && $wgTransactionalTimeLimit > $timeLimit ) {
3349                 set_time_limit( $wgTransactionalTimeLimit );
3350         }
3351
3352         ignore_user_abort( true ); // ignore client disconnects
3353
3354         return $timeLimit;
3355 }
3356
3357 /**
3358  * Converts shorthand byte notation to integer form
3359  *
3360  * @param string $string
3361  * @param int $default Returned if $string is empty
3362  * @return int
3363  */
3364 function wfShorthandToInteger( $string = '', $default = -1 ) {
3365         $string = trim( $string );
3366         if ( $string === '' ) {
3367                 return $default;
3368         }
3369         $last = $string[strlen( $string ) - 1];
3370         $val = intval( $string );
3371         switch ( $last ) {
3372                 case 'g':
3373                 case 'G':
3374                         $val *= 1024;
3375                         // break intentionally missing
3376                 case 'm':
3377                 case 'M':
3378                         $val *= 1024;
3379                         // break intentionally missing
3380                 case 'k':
3381                 case 'K':
3382                         $val *= 1024;
3383         }
3384
3385         return $val;
3386 }
3387
3388 /**
3389  * Get the normalised IETF language tag
3390  * See unit test for examples.
3391  *
3392  * @param string $code The language code.
3393  * @return string The language code which complying with BCP 47 standards.
3394  */
3395 function wfBCP47( $code ) {
3396         $codeSegment = explode( '-', $code );
3397         $codeBCP = [];
3398         foreach ( $codeSegment as $segNo => $seg ) {
3399                 // when previous segment is x, it is a private segment and should be lc
3400                 if ( $segNo > 0 && strtolower( $codeSegment[( $segNo - 1 )] ) == 'x' ) {
3401                         $codeBCP[$segNo] = strtolower( $seg );
3402                 // ISO 3166 country code
3403                 } elseif ( ( strlen( $seg ) == 2 ) && ( $segNo > 0 ) ) {
3404                         $codeBCP[$segNo] = strtoupper( $seg );
3405                 // ISO 15924 script code
3406                 } elseif ( ( strlen( $seg ) == 4 ) && ( $segNo > 0 ) ) {
3407                         $codeBCP[$segNo] = ucfirst( strtolower( $seg ) );
3408                 // Use lowercase for other cases
3409                 } else {
3410                         $codeBCP[$segNo] = strtolower( $seg );
3411                 }
3412         }
3413         $langCode = implode( '-', $codeBCP );
3414         return $langCode;
3415 }
3416
3417 /**
3418  * Get a specific cache object.
3419  *
3420  * @param int|string $cacheType A CACHE_* constants, or other key in $wgObjectCaches
3421  * @return BagOStuff
3422  */
3423 function wfGetCache( $cacheType ) {
3424         return ObjectCache::getInstance( $cacheType );
3425 }
3426
3427 /**
3428  * Get the main cache object
3429  *
3430  * @return BagOStuff
3431  */
3432 function wfGetMainCache() {
3433         global $wgMainCacheType;
3434         return ObjectCache::getInstance( $wgMainCacheType );
3435 }
3436
3437 /**
3438  * Get the cache object used by the message cache
3439  *
3440  * @return BagOStuff
3441  */
3442 function wfGetMessageCacheStorage() {
3443         global $wgMessageCacheType;
3444         return ObjectCache::getInstance( $wgMessageCacheType );
3445 }
3446
3447 /**
3448  * Get the cache object used by the parser cache
3449  *
3450  * @return BagOStuff
3451  */
3452 function wfGetParserCacheStorage() {
3453         global $wgParserCacheType;
3454         return ObjectCache::getInstance( $wgParserCacheType );
3455 }
3456
3457 /**
3458  * Call hook functions defined in $wgHooks
3459  *
3460  * @param string $event Event name
3461  * @param array $args Parameters passed to hook functions
3462  * @param string|null $deprecatedVersion Optionally mark hook as deprecated with version number
3463  *
3464  * @return bool True if no handler aborted the hook
3465  * @deprecated since 1.25 - use Hooks::run
3466  */
3467 function wfRunHooks( $event, array $args = [], $deprecatedVersion = null ) {
3468         return Hooks::run( $event, $args, $deprecatedVersion );
3469 }
3470
3471 /**
3472  * Wrapper around php's unpack.
3473  *
3474  * @param string $format The format string (See php's docs)
3475  * @param string $data A binary string of binary data
3476  * @param int|bool $length The minimum length of $data or false. This is to
3477  *      prevent reading beyond the end of $data. false to disable the check.
3478  *
3479  * Also be careful when using this function to read unsigned 32 bit integer
3480  * because php might make it negative.
3481  *
3482  * @throws MWException If $data not long enough, or if unpack fails
3483  * @return array Associative array of the extracted data
3484  */
3485 function wfUnpack( $format, $data, $length = false ) {
3486         if ( $length !== false ) {
3487                 $realLen = strlen( $data );
3488                 if ( $realLen < $length ) {
3489                         throw new MWException( "Tried to use wfUnpack on a "
3490                                 . "string of length $realLen, but needed one "
3491                                 . "of at least length $length."
3492                         );
3493                 }
3494         }
3495
3496         MediaWiki\suppressWarnings();
3497         $result = unpack( $format, $data );
3498         MediaWiki\restoreWarnings();
3499
3500         if ( $result === false ) {
3501                 // If it cannot extract the packed data.
3502                 throw new MWException( "unpack could not unpack binary data" );
3503         }
3504         return $result;
3505 }
3506
3507 /**
3508  * Determine if an image exists on the 'bad image list'.
3509  *
3510  * The format of MediaWiki:Bad_image_list is as follows:
3511  *    * Only list items (lines starting with "*") are considered
3512  *    * The first link on a line must be a link to a bad image
3513  *    * Any subsequent links on the same line are considered to be exceptions,
3514  *      i.e. articles where the image may occur inline.
3515  *
3516  * @param string $name The image name to check
3517  * @param Title|bool $contextTitle The page on which the image occurs, if known
3518  * @param string $blacklist Wikitext of a file blacklist
3519  * @return bool
3520  */
3521 function wfIsBadImage( $name, $contextTitle = false, $blacklist = null ) {
3522         # Handle redirects; callers almost always hit wfFindFile() anyway,
3523         # so just use that method because it has a fast process cache.
3524         $file = wfFindFile( $name ); // get the final name
3525         $name = $file ? $file->getTitle()->getDBkey() : $name;
3526
3527         # Run the extension hook
3528         $bad = false;
3529         if ( !Hooks::run( 'BadImage', [ $name, &$bad ] ) ) {
3530                 return (bool)$bad;
3531         }
3532
3533         $cache = ObjectCache::getLocalServerInstance( 'hash' );
3534         $key = $cache->makeKey(
3535                 'bad-image-list', ( $blacklist === null ) ? 'default' : md5( $blacklist )
3536         );
3537         $badImages = $cache->get( $key );
3538
3539         if ( $badImages === false ) { // cache miss
3540                 if ( $blacklist === null ) {
3541                         $blacklist = wfMessage( 'bad_image_list' )->inContentLanguage()->plain(); // site list
3542                 }
3543                 # Build the list now
3544                 $badImages = [];
3545                 $lines = explode( "\n", $blacklist );
3546                 foreach ( $lines as $line ) {
3547                         # List items only
3548                         if ( substr( $line, 0, 1 ) !== '*' ) {
3549                                 continue;
3550                         }
3551
3552                         # Find all links
3553                         $m = [];
3554                         if ( !preg_match_all( '/\[\[:?(.*?)\]\]/', $line, $m ) ) {
3555                                 continue;
3556                         }
3557
3558                         $exceptions = [];
3559                         $imageDBkey = false;
3560                         foreach ( $m[1] as $i => $titleText ) {
3561                                 $title = Title::newFromText( $titleText );
3562                                 if ( !is_null( $title ) ) {
3563                                         if ( $i == 0 ) {
3564                                                 $imageDBkey = $title->getDBkey();
3565                                         } else {
3566                                                 $exceptions[$title->getPrefixedDBkey()] = true;
3567                                         }
3568                                 }
3569                         }
3570
3571                         if ( $imageDBkey !== false ) {
3572                                 $badImages[$imageDBkey] = $exceptions;
3573                         }
3574                 }
3575                 $cache->set( $key, $badImages, 60 );
3576         }
3577
3578         $contextKey = $contextTitle ? $contextTitle->getPrefixedDBkey() : false;
3579         $bad = isset( $badImages[$name] ) && !isset( $badImages[$name][$contextKey] );
3580
3581         return $bad;
3582 }
3583
3584 /**
3585  * Determine whether the client at a given source IP is likely to be able to
3586  * access the wiki via HTTPS.
3587  *
3588  * @param string $ip The IPv4/6 address in the normal human-readable form
3589  * @return bool
3590  */
3591 function wfCanIPUseHTTPS( $ip ) {
3592         $canDo = true;
3593         Hooks::run( 'CanIPUseHTTPS', [ $ip, &$canDo ] );
3594         return !!$canDo;
3595 }
3596
3597 /**
3598  * Determine input string is represents as infinity
3599  *
3600  * @param string $str The string to determine
3601  * @return bool
3602  * @since 1.25
3603  */
3604 function wfIsInfinity( $str ) {
3605         $infinityValues = [ 'infinite', 'indefinite', 'infinity', 'never' ];
3606         return in_array( $str, $infinityValues );
3607 }
3608
3609 /**
3610  * Returns true if these thumbnail parameters match one that MediaWiki
3611  * requests from file description pages and/or parser output.
3612  *
3613  * $params is considered non-standard if they involve a non-standard
3614  * width or any non-default parameters aside from width and page number.
3615  * The number of possible files with standard parameters is far less than
3616  * that of all combinations; rate-limiting for them can thus be more generious.
3617  *
3618  * @param File $file
3619  * @param array $params
3620  * @return bool
3621  * @since 1.24 Moved from thumb.php to GlobalFunctions in 1.25
3622  */
3623 function wfThumbIsStandard( File $file, array $params ) {
3624         global $wgThumbLimits, $wgImageLimits, $wgResponsiveImages;
3625
3626         $multipliers = [ 1 ];
3627         if ( $wgResponsiveImages ) {
3628                 // These available sizes are hardcoded currently elsewhere in MediaWiki.
3629                 // @see Linker::processResponsiveImages
3630                 $multipliers[] = 1.5;
3631                 $multipliers[] = 2;
3632         }
3633
3634         $handler = $file->getHandler();
3635         if ( !$handler || !isset( $params['width'] ) ) {
3636                 return false;
3637         }
3638
3639         $basicParams = [];
3640         if ( isset( $params['page'] ) ) {
3641                 $basicParams['page'] = $params['page'];
3642         }
3643
3644         $thumbLimits = [];
3645         $imageLimits = [];
3646         // Expand limits to account for multipliers
3647         foreach ( $multipliers as $multiplier ) {
3648                 $thumbLimits = array_merge( $thumbLimits, array_map(
3649                         function ( $width ) use ( $multiplier ) {
3650                                 return round( $width * $multiplier );
3651                         }, $wgThumbLimits )
3652                 );
3653                 $imageLimits = array_merge( $imageLimits, array_map(
3654                         function ( $pair ) use ( $multiplier ) {
3655                                 return [
3656                                         round( $pair[0] * $multiplier ),
3657                                         round( $pair[1] * $multiplier ),
3658                                 ];
3659                         }, $wgImageLimits )
3660                 );
3661         }
3662
3663         // Check if the width matches one of $wgThumbLimits
3664         if ( in_array( $params['width'], $thumbLimits ) ) {
3665                 $normalParams = $basicParams + [ 'width' => $params['width'] ];
3666                 // Append any default values to the map (e.g. "lossy", "lossless", ...)
3667                 $handler->normaliseParams( $file, $normalParams );
3668         } else {
3669                 // If not, then check if the width matchs one of $wgImageLimits
3670                 $match = false;
3671                 foreach ( $imageLimits as $pair ) {
3672                         $normalParams = $basicParams + [ 'width' => $pair[0], 'height' => $pair[1] ];
3673                         // Decide whether the thumbnail should be scaled on width or height.
3674                         // Also append any default values to the map (e.g. "lossy", "lossless", ...)
3675                         $handler->normaliseParams( $file, $normalParams );
3676                         // Check if this standard thumbnail size maps to the given width
3677                         if ( $normalParams['width'] == $params['width'] ) {
3678                                 $match = true;
3679                                 break;
3680                         }
3681                 }
3682                 if ( !$match ) {
3683                         return false; // not standard for description pages
3684                 }
3685         }
3686
3687         // Check that the given values for non-page, non-width, params are just defaults
3688         foreach ( $params as $key => $value ) {
3689                 if ( !isset( $normalParams[$key] ) || $normalParams[$key] != $value ) {
3690                         return false;
3691                 }
3692         }
3693
3694         return true;
3695 }
3696
3697 /**
3698  * Merges two (possibly) 2 dimensional arrays into the target array ($baseArray).
3699  *
3700  * Values that exist in both values will be combined with += (all values of the array
3701  * of $newValues will be added to the values of the array of $baseArray, while values,
3702  * that exists in both, the value of $baseArray will be used).
3703  *
3704  * @param array $baseArray The array where you want to add the values of $newValues to
3705  * @param array $newValues An array with new values
3706  * @return array The combined array
3707  * @since 1.26
3708  */
3709 function wfArrayPlus2d( array $baseArray, array $newValues ) {
3710         // First merge items that are in both arrays
3711         foreach ( $baseArray as $name => &$groupVal ) {
3712                 if ( isset( $newValues[$name] ) ) {
3713                         $groupVal += $newValues[$name];
3714                 }
3715         }
3716         // Now add items that didn't exist yet
3717         $baseArray += $newValues;
3718
3719         return $baseArray;
3720 }