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 MediaWiki\Logger\LoggerFactory;
  28 use MediaWiki\ProcOpenError;
  29 use MediaWiki\Session\SessionManager;
  30 use MediaWiki\MediaWikiServices;
  31 use MediaWiki\Shell\Shell;
  32 use Wikimedia\ScopedCallback;
  33 use Wikimedia\Rdbms\DBReplicationWaitError;
  34
  35 // Hide compatibility functions from Doxygen
  36 /// @cond
  37 /**
  38  * Compatibility functions
  39  *
  40  * We support PHP 5.5.9 and up.
  41  * Re-implementations of newer functions or functions in non-standard
  42  * PHP extensions may be included here.
  43  */
  44
  45 // hash_equals function only exists in PHP >= 5.6.0
  46 // https://secure.php.net/hash_equals
  47 if ( !function_exists( 'hash_equals' ) ) {
  48         /**
  49          * Check whether a user-provided string is equal to a fixed-length secret string
  50          * without revealing bytes of the secret string through timing differences.
  51          *
  52          * The usual way to compare strings (PHP's === operator or the underlying memcmp()
  53          * function in C) is to compare corresponding bytes and stop at the first difference,
  54          * which would take longer for a partial match than for a complete mismatch. This
  55          * is not secure when one of the strings (e.g. an HMAC or token) must remain secret
  56          * and the other may come from an attacker. Statistical analysis of timing measurements
  57          * over many requests may allow the attacker to guess the string's bytes one at a time
  58          * (and check his guesses) even if the timing differences are extremely small.
  59          *
  60          * When making such a security-sensitive comparison, it is essential that the sequence
  61          * in which instructions are executed and memory locations are accessed not depend on
  62          * the secret string's value. HOWEVER, for simplicity, we do not attempt to minimize
  63          * the inevitable leakage of the string's length. That is generally known anyway as
  64          * a chararacteristic of the hash function used to compute the secret value.
  65          *
  66          * Longer explanation: http://www.emerose.com/timing-attacks-explained
  67          *
  68          * @codeCoverageIgnore
  69          * @param string $known_string Fixed-length secret string to compare against
  70          * @param string $user_string User-provided string
  71          * @return bool True if the strings are the same, false otherwise
  72          */
  73         function hash_equals( $known_string, $user_string ) {
  74                 // Strict type checking as in PHP's native implementation
  75                 if ( !is_string( $known_string ) ) {
  76                         trigger_error( 'hash_equals(): Expected known_string to be a string, ' .
  77                                 gettype( $known_string ) . ' given', E_USER_WARNING );
  78
  79                         return false;
  80                 }
  81
  82                 if ( !is_string( $user_string ) ) {
  83                         trigger_error( 'hash_equals(): Expected user_string to be a string, ' .
  84                                 gettype( $user_string ) . ' given', E_USER_WARNING );
  85
  86                         return false;
  87                 }
  88
  89                 $known_string_len = strlen( $known_string );
  90                 if ( $known_string_len !== strlen( $user_string ) ) {
  91                         return false;
  92                 }
  93
  94                 $result = 0;
  95                 for ( $i = 0; $i < $known_string_len; $i++ ) {
  96                         $result |= ord( $known_string[$i] ) ^ ord( $user_string[$i] );
  97                 }
  98
  99                 return ( $result === 0 );
 100         }
 101 }
 102 /// @endcond
 103
 104 /**
 105  * Load an extension
 106  *
 107  * This queues an extension to be loaded through
 108  * the ExtensionRegistry system.
 109  *
 110  * @param string $ext Name of the extension to load
 111  * @param string|null $path Absolute path of where to find the extension.json file
 112  * @since 1.25
 113  */
 114 function wfLoadExtension( $ext, $path = null ) {
 115         if ( !$path ) {
 116                 global $wgExtensionDirectory;
 117                 $path = "$wgExtensionDirectory/$ext/extension.json";
 118         }
 119         ExtensionRegistry::getInstance()->queue( $path );
 120 }
 121
 122 /**
 123  * Load multiple extensions at once
 124  *
 125  * Same as wfLoadExtension, but more efficient if you
 126  * are loading multiple extensions.
 127  *
 128  * If you want to specify custom paths, you should interact with
 129  * ExtensionRegistry directly.
 130  *
 131  * @see wfLoadExtension
 132  * @param string[] $exts Array of extension names to load
 133  * @since 1.25
 134  */
 135 function wfLoadExtensions( array $exts ) {
 136         global $wgExtensionDirectory;
 137         $registry = ExtensionRegistry::getInstance();
 138         foreach ( $exts as $ext ) {
 139                 $registry->queue( "$wgExtensionDirectory/$ext/extension.json" );
 140         }
 141 }
 142
 143 /**
 144  * Load a skin
 145  *
 146  * @see wfLoadExtension
 147  * @param string $skin Name of the extension to load
 148  * @param string|null $path Absolute path of where to find the skin.json file
 149  * @since 1.25
 150  */
 151 function wfLoadSkin( $skin, $path = null ) {
 152         if ( !$path ) {
 153                 global $wgStyleDirectory;
 154                 $path = "$wgStyleDirectory/$skin/skin.json";
 155         }
 156         ExtensionRegistry::getInstance()->queue( $path );
 157 }
 158
 159 /**
 160  * Load multiple skins at once
 161  *
 162  * @see wfLoadExtensions
 163  * @param string[] $skins Array of extension names to load
 164  * @since 1.25
 165  */
 166 function wfLoadSkins( array $skins ) {
 167         global $wgStyleDirectory;
 168         $registry = ExtensionRegistry::getInstance();
 169         foreach ( $skins as $skin ) {
 170                 $registry->queue( "$wgStyleDirectory/$skin/skin.json" );
 171         }
 172 }
 173
 174 /**
 175  * Like array_diff( $a, $b ) except that it works with two-dimensional arrays.
 176  * @param array $a
 177  * @param array $b
 178  * @return array
 179  */
 180 function wfArrayDiff2( $a, $b ) {
 181         return array_udiff( $a, $b, 'wfArrayDiff2_cmp' );
 182 }
 183
 184 /**
 185  * @param array|string $a
 186  * @param array|string $b
 187  * @return int
 188  */
 189 function wfArrayDiff2_cmp( $a, $b ) {
 190         if ( is_string( $a ) && is_string( $b ) ) {
 191                 return strcmp( $a, $b );
 192         } elseif ( count( $a ) !== count( $b ) ) {
 193                 return count( $a ) < count( $b ) ? -1 : 1;
 194         } else {
 195                 reset( $a );
 196                 reset( $b );
 197                 while ( key( $a ) !== null && key( $b ) !== null ) {
 198                         $valueA = current( $a );
 199                         $valueB = current( $b );
 200                         $cmp = strcmp( $valueA, $valueB );
 201                         if ( $cmp !== 0 ) {
 202                                 return $cmp;
 203                         }
 204                         next( $a );
 205                         next( $b );
 206                 }
 207                 return 0;
 208         }
 209 }
 210
 211 /**
 212  * Like array_filter with ARRAY_FILTER_USE_BOTH, but works pre-5.6.
 213  *
 214  * @param array $arr
 215  * @param callable $callback Will be called with the array value and key (in that order) and
 216  *   should return a bool which will determine whether the array element is kept.
 217  * @return array
 218  */
 219 function wfArrayFilter( array $arr, callable $callback ) {
 220         if ( defined( 'ARRAY_FILTER_USE_BOTH' ) ) {
 221                 return array_filter( $arr, $callback, ARRAY_FILTER_USE_BOTH );
 222         }
 223         $filteredKeys = array_filter( array_keys( $arr ), function ( $key ) use ( $arr, $callback ) {
 224                 return call_user_func( $callback, $arr[$key], $key );
 225         } );
 226         return array_intersect_key( $arr, array_fill_keys( $filteredKeys, true ) );
 227 }
 228
 229 /**
 230  * Like array_filter with ARRAY_FILTER_USE_KEY, but works pre-5.6.
 231  *
 232  * @param array $arr
 233  * @param callable $callback Will be called with the array key and should return a bool which
 234  *   will determine whether the array element is kept.
 235  * @return array
 236  */
 237 function wfArrayFilterByKey( array $arr, callable $callback ) {
 238         return wfArrayFilter( $arr, function ( $val, $key ) use ( $callback ) {
 239                 return call_user_func( $callback, $key );
 240         } );
 241 }
 242
 243 /**
 244  * Appends to second array if $value differs from that in $default
 245  *
 246  * @param string|int $key
 247  * @param mixed $value
 248  * @param mixed $default
 249  * @param array &$changed Array to alter
 250  * @throws MWException
 251  */
 252 function wfAppendToArrayIfNotDefault( $key, $value, $default, &$changed ) {
 253         if ( is_null( $changed ) ) {
 254                 throw new MWException( 'GlobalFunctions::wfAppendToArrayIfNotDefault got null' );
 255         }
 256         if ( $default[$key] !== $value ) {
 257                 $changed[$key] = $value;
 258         }
 259 }
 260
 261 /**
 262  * Merge arrays in the style of getUserPermissionsErrors, with duplicate removal
 263  * e.g.
 264  *     wfMergeErrorArrays(
 265  *       [ [ 'x' ] ],
 266  *       [ [ 'x', '2' ] ],
 267  *       [ [ 'x' ] ],
 268  *       [ [ 'y' ] ]
 269  *     );
 270  * returns:
 271  *     [
 272  *       [ 'x', '2' ],
 273  *       [ 'x' ],
 274  *       [ 'y' ]
 275  *     ]
 276  *
 277  * @param array $array1,...
 278  * @return array
 279  */
 280 function wfMergeErrorArrays( /*...*/ ) {
 281         $args = func_get_args();
 282         $out = [];
 283         foreach ( $args as $errors ) {
 284                 foreach ( $errors as $params ) {
 285                         $originalParams = $params;
 286                         if ( $params[0] instanceof MessageSpecifier ) {
 287                                 $msg = $params[0];
 288                                 $params = array_merge( [ $msg->getKey() ], $msg->getParams() );
 289                         }
 290                         # @todo FIXME: Sometimes get nested arrays for $params,
 291                         # which leads to E_NOTICEs
 292                         $spec = implode( "\t", $params );
 293                         $out[$spec] = $originalParams;
 294                 }
 295         }
 296         return array_values( $out );
 297 }
 298
 299 /**
 300  * Insert array into another array after the specified *KEY*
 301  *
 302  * @param array $array The array.
 303  * @param array $insert The array to insert.
 304  * @param mixed $after The key to insert after
 305  * @return array
 306  */
 307 function wfArrayInsertAfter( array $array, array $insert, $after ) {
 308         // Find the offset of the element to insert after.
 309         $keys = array_keys( $array );
 310         $offsetByKey = array_flip( $keys );
 311
 312         $offset = $offsetByKey[$after];
 313
 314         // Insert at the specified offset
 315         $before = array_slice( $array, 0, $offset + 1, true );
 316         $after = array_slice( $array, $offset + 1, count( $array ) - $offset, true );
 317
 318         $output = $before + $insert + $after;
 319
 320         return $output;
 321 }
 322
 323 /**
 324  * Recursively converts the parameter (an object) to an array with the same data
 325  *
 326  * @param object|array $objOrArray
 327  * @param bool $recursive
 328  * @return array
 329  */
 330 function wfObjectToArray( $objOrArray, $recursive = true ) {
 331         $array = [];
 332         if ( is_object( $objOrArray ) ) {
 333                 $objOrArray = get_object_vars( $objOrArray );
 334         }
 335         foreach ( $objOrArray as $key => $value ) {
 336                 if ( $recursive && ( is_object( $value ) || is_array( $value ) ) ) {
 337                         $value = wfObjectToArray( $value );
 338                 }
 339
 340                 $array[$key] = $value;
 341         }
 342
 343         return $array;
 344 }
 345
 346 /**
 347  * Get a random decimal value between 0 and 1, in a way
 348  * not likely to give duplicate values for any realistic
 349  * number of articles.
 350  *
 351  * @note This is designed for use in relation to Special:RandomPage
 352  *       and the page_random database field.
 353  *
 354  * @return string
 355  */
 356 function wfRandom() {
 357         // The maximum random value is "only" 2^31-1, so get two random
 358         // values to reduce the chance of dupes
 359         $max = mt_getrandmax() + 1;
 360         $rand = number_format( ( mt_rand() * $max + mt_rand() ) / $max / $max, 12, '.', '' );
 361         return $rand;
 362 }
 363
 364 /**
 365  * Get a random string containing a number of pseudo-random hex characters.
 366  *
 367  * @note This is not secure, if you are trying to generate some sort
 368  *       of token please use MWCryptRand instead.
 369  *
 370  * @param int $length The length of the string to generate
 371  * @return string
 372  * @since 1.20
 373  */
 374 function wfRandomString( $length = 32 ) {
 375         $str = '';
 376         for ( $n = 0; $n < $length; $n += 7 ) {
 377                 $str .= sprintf( '%07x', mt_rand() & 0xfffffff );
 378         }
 379         return substr( $str, 0, $length );
 380 }
 381
 382 /**
 383  * We want some things to be included as literal characters in our title URLs
 384  * for prettiness, which urlencode encodes by default.  According to RFC 1738,
 385  * all of the following should be safe:
 386  *
 387  * ;:@&=$-_.+!*'(),
 388  *
 389  * RFC 1738 says ~ is unsafe, however RFC 3986 considers it an unreserved
 390  * character which should not be encoded. More importantly, google chrome
 391  * always converts %7E back to ~, and converting it in this function can
 392  * cause a redirect loop (T105265).
 393  *
 394  * But + is not safe because it's used to indicate a space; &= are only safe in
 395  * paths and not in queries (and we don't distinguish here); ' seems kind of
 396  * scary; and urlencode() doesn't touch -_. to begin with.  Plus, although /
 397  * is reserved, we don't care.  So the list we unescape is:
 398  *
 399  * ;:@$!*(),/~
 400  *
 401  * However, IIS7 redirects fail when the url contains a colon (see T24709),
 402  * so no fancy : for IIS7.
 403  *
 404  * %2F in the page titles seems to fatally break for some reason.
 405  *
 406  * @param string $s
 407  * @return string
 408  */
 409 function wfUrlencode( $s ) {
 410         static $needle;
 411
 412         if ( is_null( $s ) ) {
 413                 $needle = null;
 414                 return '';
 415         }
 416
 417         if ( is_null( $needle ) ) {
 418                 $needle = [ '%3B', '%40', '%24', '%21', '%2A', '%28', '%29', '%2C', '%2F', '%7E' ];
 419                 if ( !isset( $_SERVER['SERVER_SOFTWARE'] ) ||
 420                         ( strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/7' ) === false )
 421                 ) {
 422                         $needle[] = '%3A';
 423                 }
 424         }
 425
 426         $s = urlencode( $s );
 427         $s = str_ireplace(
 428                 $needle,
 429                 [ ';', '@', '$', '!', '*', '(', ')', ',', '/', '~', ':' ],
 430                 $s
 431         );
 432
 433         return $s;
 434 }
 435
 436 /**
 437  * This function takes one or two arrays as input, and returns a CGI-style string, e.g.
 438  * "days=7&limit=100". Options in the first array override options in the second.
 439  * Options set to null or false will not be output.
 440  *
 441  * @param array $array1 ( String|Array )
 442  * @param array|null $array2 ( String|Array )
 443  * @param string $prefix
 444  * @return string
 445  */
 446 function wfArrayToCgi( $array1, $array2 = null, $prefix = '' ) {
 447         if ( !is_null( $array2 ) ) {
 448                 $array1 = $array1 + $array2;
 449         }
 450
 451         $cgi = '';
 452         foreach ( $array1 as $key => $value ) {
 453                 if ( !is_null( $value ) && $value !== false ) {
 454                         if ( $cgi != '' ) {
 455                                 $cgi .= '&';
 456                         }
 457                         if ( $prefix !== '' ) {
 458                                 $key = $prefix . "[$key]";
 459                         }
 460                         if ( is_array( $value ) ) {
 461                                 $firstTime = true;
 462                                 foreach ( $value as $k => $v ) {
 463                                         $cgi .= $firstTime ? '' : '&';
 464                                         if ( is_array( $v ) ) {
 465                                                 $cgi .= wfArrayToCgi( $v, null, $key . "[$k]" );
 466                                         } else {
 467                                                 $cgi .= urlencode( $key . "[$k]" ) . '=' . urlencode( $v );
 468                                         }
 469                                         $firstTime = false;
 470                                 }
 471                         } else {
 472                                 if ( is_object( $value ) ) {
 473                                         $value = $value->__toString();
 474                                 }
 475                                 $cgi .= urlencode( $key ) . '=' . urlencode( $value );
 476                         }
 477                 }
 478         }
 479         return $cgi;
 480 }
 481
 482 /**
 483  * This is the logical opposite of wfArrayToCgi(): it accepts a query string as
 484  * its argument and returns the same string in array form.  This allows compatibility
 485  * with legacy functions that accept raw query strings instead of nice
 486  * arrays.  Of course, keys and values are urldecode()d.
 487  *
 488  * @param string $query Query string
 489  * @return string[] Array version of input
 490  */
 491 function wfCgiToArray( $query ) {
 492         if ( isset( $query[0] ) && $query[0] == '?' ) {
 493                 $query = substr( $query, 1 );
 494         }
 495         $bits = explode( '&', $query );
 496         $ret = [];
 497         foreach ( $bits as $bit ) {
 498                 if ( $bit === '' ) {
 499                         continue;
 500                 }
 501                 if ( strpos( $bit, '=' ) === false ) {
 502                         // Pieces like &qwerty become 'qwerty' => '' (at least this is what php does)
 503                         $key = $bit;
 504                         $value = '';
 505                 } else {
 506                         list( $key, $value ) = explode( '=', $bit );
 507                 }
 508                 $key = urldecode( $key );
 509                 $value = urldecode( $value );
 510                 if ( strpos( $key, '[' ) !== false ) {
 511                         $keys = array_reverse( explode( '[', $key ) );
 512                         $key = array_pop( $keys );
 513                         $temp = $value;
 514                         foreach ( $keys as $k ) {
 515                                 $k = substr( $k, 0, -1 );
 516                                 $temp = [ $k => $temp ];
 517                         }
 518                         if ( isset( $ret[$key] ) ) {
 519                                 $ret[$key] = array_merge( $ret[$key], $temp );
 520                         } else {
 521                                 $ret[$key] = $temp;
 522                         }
 523                 } else {
 524                         $ret[$key] = $value;
 525                 }
 526         }
 527         return $ret;
 528 }
 529
 530 /**
 531  * Append a query string to an existing URL, which may or may not already
 532  * have query string parameters already. If so, they will be combined.
 533  *
 534  * @param string $url
 535  * @param string|string[] $query String or associative array
 536  * @return string
 537  */
 538 function wfAppendQuery( $url, $query ) {
 539         if ( is_array( $query ) ) {
 540                 $query = wfArrayToCgi( $query );
 541         }
 542         if ( $query != '' ) {
 543                 // Remove the fragment, if there is one
 544                 $fragment = false;
 545                 $hashPos = strpos( $url, '#' );
 546                 if ( $hashPos !== false ) {
 547                         $fragment = substr( $url, $hashPos );
 548                         $url = substr( $url, 0, $hashPos );
 549                 }
 550
 551                 // Add parameter
 552                 if ( false === strpos( $url, '?' ) ) {
 553                         $url .= '?';
 554                 } else {
 555                         $url .= '&';
 556                 }
 557                 $url .= $query;
 558
 559                 // Put the fragment back
 560                 if ( $fragment !== false ) {
 561                         $url .= $fragment;
 562                 }
 563         }
 564         return $url;
 565 }
 566
 567 /**
 568  * Expand a potentially local URL to a fully-qualified URL. Assumes $wgServer
 569  * is correct.
 570  *
 571  * The meaning of the PROTO_* constants is as follows:
 572  * PROTO_HTTP: Output a URL starting with http://
 573  * PROTO_HTTPS: Output a URL starting with https://
 574  * PROTO_RELATIVE: Output a URL starting with // (protocol-relative URL)
 575  * PROTO_CURRENT: Output a URL starting with either http:// or https:// , depending
 576  *    on which protocol was used for the current incoming request
 577  * PROTO_CANONICAL: For URLs without a domain, like /w/index.php , use $wgCanonicalServer.
 578  *    For protocol-relative URLs, use the protocol of $wgCanonicalServer
 579  * PROTO_INTERNAL: Like PROTO_CANONICAL, but uses $wgInternalServer instead of $wgCanonicalServer
 580  *
 581  * @todo this won't work with current-path-relative URLs
 582  * like "subdir/foo.html", etc.
 583  *
 584  * @param string $url Either fully-qualified or a local path + query
 585  * @param string|int|null $defaultProto One of the PROTO_* constants. Determines the
 586  *    protocol to use if $url or $wgServer is protocol-relative
 587  * @return string|false Fully-qualified URL, current-path-relative URL or false if
 588  *    no valid URL can be constructed
 589  */
 590 function wfExpandUrl( $url, $defaultProto = PROTO_CURRENT ) {
 591         global $wgServer, $wgCanonicalServer, $wgInternalServer, $wgRequest,
 592                 $wgHttpsPort;
 593         if ( $defaultProto === PROTO_CANONICAL ) {
 594                 $serverUrl = $wgCanonicalServer;
 595         } elseif ( $defaultProto === PROTO_INTERNAL && $wgInternalServer !== false ) {
 596                 // Make $wgInternalServer fall back to $wgServer if not set
 597                 $serverUrl = $wgInternalServer;
 598         } else {
 599                 $serverUrl = $wgServer;
 600                 if ( $defaultProto === PROTO_CURRENT ) {
 601                         $defaultProto = $wgRequest->getProtocol() . '://';
 602                 }
 603         }
 604
 605         // Analyze $serverUrl to obtain its protocol
 606         $bits = wfParseUrl( $serverUrl );
 607         $serverHasProto = $bits && $bits['scheme'] != '';
 608
 609         if ( $defaultProto === PROTO_CANONICAL || $defaultProto === PROTO_INTERNAL ) {
 610                 if ( $serverHasProto ) {
 611                         $defaultProto = $bits['scheme'] . '://';
 612                 } else {
 613                         // $wgCanonicalServer or $wgInternalServer doesn't have a protocol.
 614                         // This really isn't supposed to happen. Fall back to HTTP in this
 615                         // ridiculous case.
 616                         $defaultProto = PROTO_HTTP;
 617                 }
 618         }
 619
 620         $defaultProtoWithoutSlashes = substr( $defaultProto, 0, -2 );
 621
 622         if ( substr( $url, 0, 2 ) == '//' ) {
 623                 $url = $defaultProtoWithoutSlashes . $url;
 624         } elseif ( substr( $url, 0, 1 ) == '/' ) {
 625                 // If $serverUrl is protocol-relative, prepend $defaultProtoWithoutSlashes,
 626                 // otherwise leave it alone.
 627                 $url = ( $serverHasProto ? '' : $defaultProtoWithoutSlashes ) . $serverUrl . $url;
 628         }
 629
 630         $bits = wfParseUrl( $url );
 631
 632         // ensure proper port for HTTPS arrives in URL
 633         // https://phabricator.wikimedia.org/T67184
 634         if ( $defaultProto === PROTO_HTTPS && $wgHttpsPort != 443 ) {
 635                 $bits['port'] = $wgHttpsPort;
 636         }
 637
 638         if ( $bits && isset( $bits['path'] ) ) {
 639                 $bits['path'] = wfRemoveDotSegments( $bits['path'] );
 640                 return wfAssembleUrl( $bits );
 641         } elseif ( $bits ) {
 642                 # No path to expand
 643                 return $url;
 644         } elseif ( substr( $url, 0, 1 ) != '/' ) {
 645                 # URL is a relative path
 646                 return wfRemoveDotSegments( $url );
 647         }
 648
 649         # Expanded URL is not valid.
 650         return false;
 651 }
 652
 653 /**
 654  * This function will reassemble a URL parsed with wfParseURL.  This is useful
 655  * if you need to edit part of a URL and put it back together.
 656  *
 657  * This is the basic structure used (brackets contain keys for $urlParts):
 658  * [scheme][delimiter][user]:[pass]@[host]:[port][path]?[query]#[fragment]
 659  *
 660  * @todo Need to integrate this into wfExpandUrl (see T34168)
 661  *
 662  * @since 1.19
 663  * @param array $urlParts URL parts, as output from wfParseUrl
 664  * @return string URL assembled from its component parts
 665  */
 666 function wfAssembleUrl( $urlParts ) {
 667         $result = '';
 668
 669         if ( isset( $urlParts['delimiter'] ) ) {
 670                 if ( isset( $urlParts['scheme'] ) ) {
 671                         $result .= $urlParts['scheme'];
 672                 }
 673
 674                 $result .= $urlParts['delimiter'];
 675         }
 676
 677         if ( isset( $urlParts['host'] ) ) {
 678                 if ( isset( $urlParts['user'] ) ) {
 679                         $result .= $urlParts['user'];
 680                         if ( isset( $urlParts['pass'] ) ) {
 681                                 $result .= ':' . $urlParts['pass'];
 682                         }
 683                         $result .= '@';
 684                 }
 685
 686                 $result .= $urlParts['host'];
 687
 688                 if ( isset( $urlParts['port'] ) ) {
 689                         $result .= ':' . $urlParts['port'];
 690                 }
 691         }
 692
 693         if ( isset( $urlParts['path'] ) ) {
 694                 $result .= $urlParts['path'];
 695         }
 696
 697         if ( isset( $urlParts['query'] ) ) {
 698                 $result .= '?' . $urlParts['query'];
 699         }
 700
 701         if ( isset( $urlParts['fragment'] ) ) {
 702                 $result .= '#' . $urlParts['fragment'];
 703         }
 704
 705         return $result;
 706 }
 707
 708 /**
 709  * Remove all dot-segments in the provided URL path.  For example,
 710  * '/a/./b/../c/' becomes '/a/c/'.  For details on the algorithm, please see
 711  * RFC3986 section 5.2.4.
 712  *
 713  * @todo Need to integrate this into wfExpandUrl (see T34168)
 714  *
 715  * @since 1.19
 716  *
 717  * @param string $urlPath URL path, potentially containing dot-segments
 718  * @return string URL path with all dot-segments removed
 719  */
 720 function wfRemoveDotSegments( $urlPath ) {
 721         $output = '';
 722         $inputOffset = 0;
 723         $inputLength = strlen( $urlPath );
 724
 725         while ( $inputOffset < $inputLength ) {
 726                 $prefixLengthOne = substr( $urlPath, $inputOffset, 1 );
 727                 $prefixLengthTwo = substr( $urlPath, $inputOffset, 2 );
 728                 $prefixLengthThree = substr( $urlPath, $inputOffset, 3 );
 729                 $prefixLengthFour = substr( $urlPath, $inputOffset, 4 );
 730                 $trimOutput = false;
 731
 732                 if ( $prefixLengthTwo == './' ) {
 733                         # Step A, remove leading "./"
 734                         $inputOffset += 2;
 735                 } elseif ( $prefixLengthThree == '../' ) {
 736                         # Step A, remove leading "../"
 737                         $inputOffset += 3;
 738                 } elseif ( ( $prefixLengthTwo == '/.' ) && ( $inputOffset + 2 == $inputLength ) ) {
 739                         # Step B, replace leading "/.$" with "/"
 740                         $inputOffset += 1;
 741                         $urlPath[$inputOffset] = '/';
 742                 } elseif ( $prefixLengthThree == '/./' ) {
 743                         # Step B, replace leading "/./" with "/"
 744                         $inputOffset += 2;
 745                 } elseif ( $prefixLengthThree == '/..' && ( $inputOffset + 3 == $inputLength ) ) {
 746                         # Step C, replace leading "/..$" with "/" and
 747                         # remove last path component in output
 748                         $inputOffset += 2;
 749                         $urlPath[$inputOffset] = '/';
 750                         $trimOutput = true;
 751                 } elseif ( $prefixLengthFour == '/../' ) {
 752                         # Step C, replace leading "/../" with "/" and
 753                         # remove last path component in output
 754                         $inputOffset += 3;
 755                         $trimOutput = true;
 756                 } elseif ( ( $prefixLengthOne == '.' ) && ( $inputOffset + 1 == $inputLength ) ) {
 757                         # Step D, remove "^.$"
 758                         $inputOffset += 1;
 759                 } elseif ( ( $prefixLengthTwo == '..' ) && ( $inputOffset + 2 == $inputLength ) ) {
 760                         # Step D, remove "^..$"
 761                         $inputOffset += 2;
 762                 } else {
 763                         # Step E, move leading path segment to output
 764                         if ( $prefixLengthOne == '/' ) {
 765                                 $slashPos = strpos( $urlPath, '/', $inputOffset + 1 );
 766                         } else {
 767                                 $slashPos = strpos( $urlPath, '/', $inputOffset );
 768                         }
 769                         if ( $slashPos === false ) {
 770                                 $output .= substr( $urlPath, $inputOffset );
 771                                 $inputOffset = $inputLength;
 772                         } else {
 773                                 $output .= substr( $urlPath, $inputOffset, $slashPos - $inputOffset );
 774                                 $inputOffset += $slashPos - $inputOffset;
 775                         }
 776                 }
 777
 778                 if ( $trimOutput ) {
 779                         $slashPos = strrpos( $output, '/' );
 780                         if ( $slashPos === false ) {
 781                                 $output = '';
 782                         } else {
 783                                 $output = substr( $output, 0, $slashPos );
 784                         }
 785                 }
 786         }
 787
 788         return $output;
 789 }
 790
 791 /**
 792  * Returns a regular expression of url protocols
 793  *
 794  * @param bool $includeProtocolRelative If false, remove '//' from the returned protocol list.
 795  *        DO NOT USE this directly, use wfUrlProtocolsWithoutProtRel() instead
 796  * @return string
 797  */
 798 function wfUrlProtocols( $includeProtocolRelative = true ) {
 799         global $wgUrlProtocols;
 800
 801         // Cache return values separately based on $includeProtocolRelative
 802         static $withProtRel = null, $withoutProtRel = null;
 803         $cachedValue = $includeProtocolRelative ? $withProtRel : $withoutProtRel;
 804         if ( !is_null( $cachedValue ) ) {
 805                 return $cachedValue;
 806         }
 807
 808         // Support old-style $wgUrlProtocols strings, for backwards compatibility
 809         // with LocalSettings files from 1.5
 810         if ( is_array( $wgUrlProtocols ) ) {
 811                 $protocols = [];
 812                 foreach ( $wgUrlProtocols as $protocol ) {
 813                         // Filter out '//' if !$includeProtocolRelative
 814                         if ( $includeProtocolRelative || $protocol !== '//' ) {
 815                                 $protocols[] = preg_quote( $protocol, '/' );
 816                         }
 817                 }
 818
 819                 $retval = implode( '|', $protocols );
 820         } else {
 821                 // Ignore $includeProtocolRelative in this case
 822                 // This case exists for pre-1.6 compatibility, and we can safely assume
 823                 // that '//' won't appear in a pre-1.6 config because protocol-relative
 824                 // URLs weren't supported until 1.18
 825                 $retval = $wgUrlProtocols;
 826         }
 827
 828         // Cache return value
 829         if ( $includeProtocolRelative ) {
 830                 $withProtRel = $retval;
 831         } else {
 832                 $withoutProtRel = $retval;
 833         }
 834         return $retval;
 835 }
 836
 837 /**
 838  * Like wfUrlProtocols(), but excludes '//' from the protocol list. Use this if
 839  * you need a regex that matches all URL protocols but does not match protocol-
 840  * relative URLs
 841  * @return string
 842  */
 843 function wfUrlProtocolsWithoutProtRel() {
 844         return wfUrlProtocols( false );
 845 }
 846
 847 /**
 848  * parse_url() work-alike, but non-broken.  Differences:
 849  *
 850  * 1) Does not raise warnings on bad URLs (just returns false).
 851  * 2) Handles protocols that don't use :// (e.g., mailto: and news:, as well as
 852  *    protocol-relative URLs) correctly.
 853  * 3) Adds a "delimiter" element to the array (see (2)).
 854  * 4) Verifies that the protocol is on the $wgUrlProtocols whitelist.
 855  * 5) Rejects some invalid URLs that parse_url doesn't, e.g. the empty string or URLs starting with
 856  *    a line feed character.
 857  *
 858  * @param string $url A URL to parse
 859  * @return string[]|bool Bits of the URL in an associative array, or false on failure.
 860  *   Possible fields:
 861  *   - scheme: URI scheme (protocol), e.g. 'http', 'mailto'. Lowercase, always present, but can
 862  *       be an empty string for protocol-relative URLs.
 863  *   - delimiter: either '://', ':' or '//'. Always present.
 864  *   - host: domain name / IP. Always present, but could be an empty string, e.g. for file: URLs.
 865  *   - user: user name, e.g. for HTTP Basic auth URLs such as http://user:pass@example.com/
 866  *       Missing when there is no username.
 867  *   - pass: password, same as above.
 868  *   - path: path including the leading /. Will be missing when empty (e.g. 'http://example.com')
 869  *   - query: query string (as a string; see wfCgiToArray() for parsing it), can be missing.
 870  *   - fragment: the part after #, can be missing.
 871  */
 872 function wfParseUrl( $url ) {
 873         global $wgUrlProtocols; // Allow all protocols defined in DefaultSettings/LocalSettings.php
 874
 875         // Protocol-relative URLs are handled really badly by parse_url(). It's so
 876         // bad that the easiest way to handle them is to just prepend 'http:' and
 877         // strip the protocol out later.
 878         $wasRelative = substr( $url, 0, 2 ) == '//';
 879         if ( $wasRelative ) {
 880                 $url = "http:$url";
 881         }
 882         Wikimedia\suppressWarnings();
 883         $bits = parse_url( $url );
 884         Wikimedia\restoreWarnings();
 885         // parse_url() returns an array without scheme for some invalid URLs, e.g.
 886         // parse_url("%0Ahttp://example.com") == [ 'host' => '%0Ahttp', 'path' => 'example.com' ]
 887         if ( !$bits || !isset( $bits['scheme'] ) ) {
 888                 return false;
 889         }
 890
 891         // parse_url() incorrectly handles schemes case-sensitively. Convert it to lowercase.
 892         $bits['scheme'] = strtolower( $bits['scheme'] );
 893
 894         // most of the protocols are followed by ://, but mailto: and sometimes news: not, check for it
 895         if ( in_array( $bits['scheme'] . '://', $wgUrlProtocols ) ) {
 896                 $bits['delimiter'] = '://';
 897         } elseif ( in_array( $bits['scheme'] . ':', $wgUrlProtocols ) ) {
 898                 $bits['delimiter'] = ':';
 899                 // parse_url detects for news: and mailto: the host part of an url as path
 900                 // We have to correct this wrong detection
 901                 if ( isset( $bits['path'] ) ) {
 902                         $bits['host'] = $bits['path'];
 903                         $bits['path'] = '';
 904                 }
 905         } else {
 906                 return false;
 907         }
 908
 909         /* Provide an empty host for eg. file:/// urls (see T30627) */
 910         if ( !isset( $bits['host'] ) ) {
 911                 $bits['host'] = '';
 912
 913                 // See T47069
 914                 if ( isset( $bits['path'] ) ) {
 915                         /* parse_url loses the third / for file:///c:/ urls (but not on variants) */
 916                         if ( substr( $bits['path'], 0, 1 ) !== '/' ) {
 917                                 $bits['path'] = '/' . $bits['path'];
 918                         }
 919                 } else {
 920                         $bits['path'] = '';
 921                 }
 922         }
 923
 924         // If the URL was protocol-relative, fix scheme and delimiter
 925         if ( $wasRelative ) {
 926                 $bits['scheme'] = '';
 927                 $bits['delimiter'] = '//';
 928         }
 929         return $bits;
 930 }
 931
 932 /**
 933  * Take a URL, make sure it's expanded to fully qualified, and replace any
 934  * encoded non-ASCII Unicode characters with their UTF-8 original forms
 935  * for more compact display and legibility for local audiences.
 936  *
 937  * @todo handle punycode domains too
 938  *
 939  * @param string $url
 940  * @return string
 941  */
 942 function wfExpandIRI( $url ) {
 943         return preg_replace_callback(
 944                 '/((?:%[89A-F][0-9A-F])+)/i',
 945                 'wfExpandIRI_callback',
 946                 wfExpandUrl( $url )
 947         );
 948 }
 949
 950 /**
 951  * Private callback for wfExpandIRI
 952  * @param array $matches
 953  * @return string
 954  */
 955 function wfExpandIRI_callback( $matches ) {
 956         return urldecode( $matches[1] );
 957 }
 958
 959 /**
 960  * Make URL indexes, appropriate for the el_index field of externallinks.
 961  *
 962  * @param string $url
 963  * @return array
 964  */
 965 function wfMakeUrlIndexes( $url ) {
 966         $bits = wfParseUrl( $url );
 967
 968         // Reverse the labels in the hostname, convert to lower case
 969         // For emails reverse domainpart only
 970         if ( $bits['scheme'] == 'mailto' ) {
 971                 $mailparts = explode( '@', $bits['host'], 2 );
 972                 if ( count( $mailparts ) === 2 ) {
 973                         $domainpart = strtolower( implode( '.', array_reverse( explode( '.', $mailparts[1] ) ) ) );
 974                 } else {
 975                         // No domain specified, don't mangle it
 976                         $domainpart = '';
 977                 }
 978                 $reversedHost = $domainpart . '@' . $mailparts[0];
 979         } else {
 980                 $reversedHost = strtolower( implode( '.', array_reverse( explode( '.', $bits['host'] ) ) ) );
 981         }
 982         // Add an extra dot to the end
 983         // Why? Is it in wrong place in mailto links?
 984         if ( substr( $reversedHost, -1, 1 ) !== '.' ) {
 985                 $reversedHost .= '.';
 986         }
 987         // Reconstruct the pseudo-URL
 988         $prot = $bits['scheme'];
 989         $index = $prot . $bits['delimiter'] . $reversedHost;
 990         // Leave out user and password. Add the port, path, query and fragment
 991         if ( isset( $bits['port'] ) ) {
 992                 $index .= ':' . $bits['port'];
 993         }
 994         if ( isset( $bits['path'] ) ) {
 995                 $index .= $bits['path'];
 996         } else {
 997                 $index .= '/';
 998         }
 999         if ( isset( $bits['query'] ) ) {
1000                 $index .= '?' . $bits['query'];
1001         }
1002         if ( isset( $bits['fragment'] ) ) {
1003                 $index .= '#' . $bits['fragment'];
1004         }
1005
1006         if ( $prot == '' ) {
1007                 return [ "http:$index", "https:$index" ];
1008         } else {
1009                 return [ $index ];
1010         }
1011 }
1012
1013 /**
1014  * Check whether a given URL has a domain that occurs in a given set of domains
1015  * @param string $url
1016  * @param array $domains Array of domains (strings)
1017  * @return bool True if the host part of $url ends in one of the strings in $domains
1018  */
1019 function wfMatchesDomainList( $url, $domains ) {
1020         $bits = wfParseUrl( $url );
1021         if ( is_array( $bits ) && isset( $bits['host'] ) ) {
1022                 $host = '.' . $bits['host'];
1023                 foreach ( (array)$domains as $domain ) {
1024                         $domain = '.' . $domain;
1025                         if ( substr( $host, -strlen( $domain ) ) === $domain ) {
1026                                 return true;
1027                         }
1028                 }
1029         }
1030         return false;
1031 }
1032
1033 /**
1034  * Sends a line to the debug log if enabled or, optionally, to a comment in output.
1035  * In normal operation this is a NOP.
1036  *
1037  * Controlling globals:
1038  * $wgDebugLogFile - points to the log file
1039  * $wgDebugRawPage - if false, 'action=raw' hits will not result in debug output.
1040  * $wgDebugComments - if on, some debug items may appear in comments in the HTML output.
1041  *
1042  * @since 1.25 support for additional context data
1043  *
1044  * @param string $text
1045  * @param string|bool $dest Destination of the message:
1046  *     - 'all': both to the log and HTML (debug toolbar or HTML comments)
1047  *     - 'private': excluded from HTML output
1048  *   For backward compatibility, it can also take a boolean:
1049  *     - true: same as 'all'
1050  *     - false: same as 'private'
1051  * @param array $context Additional logging context data
1052  */
1053 function wfDebug( $text, $dest = 'all', array $context = [] ) {
1054         global $wgDebugRawPage, $wgDebugLogPrefix;
1055         global $wgDebugTimestamps;
1056
1057         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
1058                 return;
1059         }
1060
1061         $text = trim( $text );
1062
1063         if ( $wgDebugTimestamps ) {
1064                 $context['seconds_elapsed'] = sprintf(
1065                         '%6.4f',
1066                         microtime( true ) - $_SERVER['REQUEST_TIME_FLOAT']
1067                 );
1068                 $context['memory_used'] = sprintf(
1069                         '%5.1fM',
1070                         ( memory_get_usage( true ) / ( 1024 * 1024 ) )
1071                 );
1072         }
1073
1074         if ( $wgDebugLogPrefix !== '' ) {
1075                 $context['prefix'] = $wgDebugLogPrefix;
1076         }
1077         $context['private'] = ( $dest === false || $dest === 'private' );
1078
1079         $logger = LoggerFactory::getInstance( 'wfDebug' );
1080         $logger->debug( $text, $context );
1081 }
1082
1083 /**
1084  * Returns true if debug logging should be suppressed if $wgDebugRawPage = false
1085  * @return bool
1086  */
1087 function wfIsDebugRawPage() {
1088         static $cache;
1089         if ( $cache !== null ) {
1090                 return $cache;
1091         }
1092         # Check for raw action using $_GET not $wgRequest, since the latter might not be initialised yet
1093         if ( ( isset( $_GET['action'] ) && $_GET['action'] == 'raw' )
1094                 || (
1095                         isset( $_SERVER['SCRIPT_NAME'] )
1096                         && substr( $_SERVER['SCRIPT_NAME'], -8 ) == 'load.php'
1097                 )
1098         ) {
1099                 $cache = true;
1100         } else {
1101                 $cache = false;
1102         }
1103         return $cache;
1104 }
1105
1106 /**
1107  * Send a line giving PHP memory usage.
1108  *
1109  * @param bool $exact Print exact byte values instead of kibibytes (default: false)
1110  */
1111 function wfDebugMem( $exact = false ) {
1112         $mem = memory_get_usage();
1113         if ( !$exact ) {
1114                 $mem = floor( $mem / 1024 ) . ' KiB';
1115         } else {
1116                 $mem .= ' B';
1117         }
1118         wfDebug( "Memory usage: $mem\n" );
1119 }
1120
1121 /**
1122  * Send a line to a supplementary debug log file, if configured, or main debug
1123  * log if not.
1124  *
1125  * To configure a supplementary log file, set $wgDebugLogGroups[$logGroup] to
1126  * a string filename or an associative array mapping 'destination' to the
1127  * desired filename. The associative array may also contain a 'sample' key
1128  * with an integer value, specifying a sampling factor. Sampled log events
1129  * will be emitted with a 1 in N random chance.
1130  *
1131  * @since 1.23 support for sampling log messages via $wgDebugLogGroups.
1132  * @since 1.25 support for additional context data
1133  * @since 1.25 sample behavior dependent on configured $wgMWLoggerDefaultSpi
1134  *
1135  * @param string $logGroup
1136  * @param string $text
1137  * @param string|bool $dest Destination of the message:
1138  *     - 'all': both to the log and HTML (debug toolbar or HTML comments)
1139  *     - 'private': only to the specific log if set in $wgDebugLogGroups and
1140  *       discarded otherwise
1141  *   For backward compatibility, it can also take a boolean:
1142  *     - true: same as 'all'
1143  *     - false: same as 'private'
1144  * @param array $context Additional logging context data
1145  */
1146 function wfDebugLog(
1147         $logGroup, $text, $dest = 'all', array $context = []
1148 ) {
1149         $text = trim( $text );
1150
1151         $logger = LoggerFactory::getInstance( $logGroup );
1152         $context['private'] = ( $dest === false || $dest === 'private' );
1153         $logger->info( $text, $context );
1154 }
1155
1156 /**
1157  * Log for database errors
1158  *
1159  * @since 1.25 support for additional context data
1160  *
1161  * @param string $text Database error message.
1162  * @param array $context Additional logging context data
1163  */
1164 function wfLogDBError( $text, array $context = [] ) {
1165         $logger = LoggerFactory::getInstance( 'wfLogDBError' );
1166         $logger->error( trim( $text ), $context );
1167 }
1168
1169 /**
1170  * Throws a warning that $function is deprecated
1171  *
1172  * @param string $function
1173  * @param string|bool $version Version of MediaWiki that the function
1174  *    was deprecated in (Added in 1.19).
1175  * @param string|bool $component Added in 1.19.
1176  * @param int $callerOffset How far up the call stack is the original
1177  *    caller. 2 = function that called the function that called
1178  *    wfDeprecated (Added in 1.20)
1179  *
1180  * @return null
1181  */
1182 function wfDeprecated( $function, $version = false, $component = false, $callerOffset = 2 ) {
1183         MWDebug::deprecated( $function, $version, $component, $callerOffset + 1 );
1184 }
1185
1186 /**
1187  * Send a warning either to the debug log or in a PHP error depending on
1188  * $wgDevelopmentWarnings. To log warnings in production, use wfLogWarning() instead.
1189  *
1190  * @param string $msg Message to send
1191  * @param int $callerOffset Number of items to go back in the backtrace to
1192  *        find the correct caller (1 = function calling wfWarn, ...)
1193  * @param int $level PHP error level; defaults to E_USER_NOTICE;
1194  *        only used when $wgDevelopmentWarnings is true
1195  */
1196 function wfWarn( $msg, $callerOffset = 1, $level = E_USER_NOTICE ) {
1197         MWDebug::warning( $msg, $callerOffset + 1, $level, 'auto' );
1198 }
1199
1200 /**
1201  * Send a warning as a PHP error and the debug log. This is intended for logging
1202  * warnings in production. For logging development warnings, use WfWarn instead.
1203  *
1204  * @param string $msg Message to send
1205  * @param int $callerOffset Number of items to go back in the backtrace to
1206  *        find the correct caller (1 = function calling wfLogWarning, ...)
1207  * @param int $level PHP error level; defaults to E_USER_WARNING
1208  */
1209 function wfLogWarning( $msg, $callerOffset = 1, $level = E_USER_WARNING ) {
1210         MWDebug::warning( $msg, $callerOffset + 1, $level, 'production' );
1211 }
1212
1213 /**
1214  * Log to a file without getting "file size exceeded" signals.
1215  *
1216  * Can also log to TCP or UDP with the syntax udp://host:port/prefix. This will
1217  * send lines to the specified port, prefixed by the specified prefix and a space.
1218  * @since 1.25 support for additional context data
1219  *
1220  * @param string $text
1221  * @param string $file Filename
1222  * @param array $context Additional logging context data
1223  * @throws MWException
1224  * @deprecated since 1.25 Use \MediaWiki\Logger\LegacyLogger::emit or UDPTransport
1225  */
1226 function wfErrorLog( $text, $file, array $context = [] ) {
1227         wfDeprecated( __METHOD__, '1.25' );
1228         $logger = LoggerFactory::getInstance( 'wfErrorLog' );
1229         $context['destination'] = $file;
1230         $logger->info( trim( $text ), $context );
1231 }
1232
1233 /**
1234  * @todo document
1235  * @todo Move logic to MediaWiki.php
1236  */
1237 function wfLogProfilingData() {
1238         global $wgDebugLogGroups, $wgDebugRawPage;
1239
1240         $context = RequestContext::getMain();
1241         $request = $context->getRequest();
1242
1243         $profiler = Profiler::instance();
1244         $profiler->setContext( $context );
1245         $profiler->logData();
1246
1247         // Send out any buffered statsd metrics as needed
1248         MediaWiki::emitBufferedStatsdData(
1249                 MediaWikiServices::getInstance()->getStatsdDataFactory(),
1250                 $context->getConfig()
1251         );
1252
1253         // Profiling must actually be enabled...
1254         if ( $profiler instanceof ProfilerStub ) {
1255                 return;
1256         }
1257
1258         if ( isset( $wgDebugLogGroups['profileoutput'] )
1259                 && $wgDebugLogGroups['profileoutput'] === false
1260         ) {
1261                 // Explicitly disabled
1262                 return;
1263         }
1264         if ( !$wgDebugRawPage && wfIsDebugRawPage() ) {
1265                 return;
1266         }
1267
1268         $ctx = [ 'elapsed' => $request->getElapsedTime() ];
1269         if ( !empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
1270                 $ctx['forwarded_for'] = $_SERVER['HTTP_X_FORWARDED_FOR'];
1271         }
1272         if ( !empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
1273                 $ctx['client_ip'] = $_SERVER['HTTP_CLIENT_IP'];
1274         }
1275         if ( !empty( $_SERVER['HTTP_FROM'] ) ) {
1276                 $ctx['from'] = $_SERVER['HTTP_FROM'];
1277         }
1278         if ( isset( $ctx['forwarded_for'] ) ||
1279                 isset( $ctx['client_ip'] ) ||
1280                 isset( $ctx['from'] ) ) {
1281                 $ctx['proxy'] = $_SERVER['REMOTE_ADDR'];
1282         }
1283
1284         // Don't load $wgUser at this late stage just for statistics purposes
1285         // @todo FIXME: We can detect some anons even if it is not loaded.
1286         // See User::getId()
1287         $user = $context->getUser();
1288         $ctx['anon'] = $user->isItemLoaded( 'id' ) && $user->isAnon();
1289
1290         // Command line script uses a FauxRequest object which does not have
1291         // any knowledge about an URL and throw an exception instead.
1292         try {
1293                 $ctx['url'] = urldecode( $request->getRequestURL() );
1294         } catch ( Exception $ignored ) {
1295                 // no-op
1296         }
1297
1298         $ctx['output'] = $profiler->getOutput();
1299
1300         $log = LoggerFactory::getInstance( 'profileoutput' );
1301         $log->info( "Elapsed: {elapsed}; URL: <{url}>\n{output}", $ctx );
1302 }
1303
1304 /**
1305  * Increment a statistics counter
1306  *
1307  * @param string $key
1308  * @param int $count
1309  * @return void
1310  */
1311 function wfIncrStats( $key, $count = 1 ) {
1312         $stats = MediaWikiServices::getInstance()->getStatsdDataFactory();
1313         $stats->updateCount( $key, $count );
1314 }
1315
1316 /**
1317  * Check whether the wiki is in read-only mode.
1318  *
1319  * @return bool
1320  */
1321 function wfReadOnly() {
1322         return MediaWikiServices::getInstance()->getReadOnlyMode()
1323                 ->isReadOnly();
1324 }
1325
1326 /**
1327  * Check if the site is in read-only mode and return the message if so
1328  *
1329  * This checks wfConfiguredReadOnlyReason() and the main load balancer
1330  * for replica DB lag. This may result in DB connection being made.
1331  *
1332  * @return string|bool String when in read-only mode; false otherwise
1333  */
1334 function wfReadOnlyReason() {
1335         return MediaWikiServices::getInstance()->getReadOnlyMode()
1336                 ->getReason();
1337 }
1338
1339 /**
1340  * Get the value of $wgReadOnly or the contents of $wgReadOnlyFile.
1341  *
1342  * @return string|bool String when in read-only mode; false otherwise
1343  * @since 1.27
1344  */
1345 function wfConfiguredReadOnlyReason() {
1346         return MediaWikiServices::getInstance()->getConfiguredReadOnlyMode()
1347                 ->getReason();
1348 }
1349
1350 /**
1351  * Return a Language object from $langcode
1352  *
1353  * @param Language|string|bool $langcode Either:
1354  *                  - a Language object
1355  *                  - code of the language to get the message for, if it is
1356  *                    a valid code create a language for that language, if
1357  *                    it is a string but not a valid code then make a basic
1358  *                    language object
1359  *                  - a boolean: if it's false then use the global object for
1360  *                    the current user's language (as a fallback for the old parameter
1361  *                    functionality), or if it is true then use global object
1362  *                    for the wiki's content language.
1363  * @return Language
1364  */
1365 function wfGetLangObj( $langcode = false ) {
1366         # Identify which language to get or create a language object for.
1367         # Using is_object here due to Stub objects.
1368         if ( is_object( $langcode ) ) {
1369                 # Great, we already have the object (hopefully)!
1370                 return $langcode;
1371         }
1372
1373         global $wgContLang, $wgLanguageCode;
1374         if ( $langcode === true || $langcode === $wgLanguageCode ) {
1375                 # $langcode is the language code of the wikis content language object.
1376                 # or it is a boolean and value is true
1377                 return $wgContLang;
1378         }
1379
1380         global $wgLang;
1381         if ( $langcode === false || $langcode === $wgLang->getCode() ) {
1382                 # $langcode is the language code of user language object.
1383                 # or it was a boolean and value is false
1384                 return $wgLang;
1385         }
1386
1387         $validCodes = array_keys( Language::fetchLanguageNames() );
1388         if ( in_array( $langcode, $validCodes ) ) {
1389                 # $langcode corresponds to a valid language.
1390                 return Language::factory( $langcode );
1391         }
1392
1393         # $langcode is a string, but not a valid language code; use content language.
1394         wfDebug( "Invalid language code passed to wfGetLangObj, falling back to content language.\n" );
1395         return $wgContLang;
1396 }
1397
1398 /**
1399  * This is the function for getting translated interface messages.
1400  *
1401  * @see Message class for documentation how to use them.
1402  * @see https://www.mediawiki.org/wiki/Manual:Messages_API
1403  *
1404  * This function replaces all old wfMsg* functions.
1405  *
1406  * @param string|string[]|MessageSpecifier $key Message key, or array of keys, or a MessageSpecifier
1407  * @param mixed $params,... Normal message parameters
1408  * @return Message
1409  *
1410  * @since 1.17
1411  *
1412  * @see Message::__construct
1413  */
1414 function wfMessage( $key /*...*/ ) {
1415         $message = new Message( $key );
1416
1417         // We call Message::params() to reduce code duplication
1418         $params = func_get_args();
1419         array_shift( $params );
1420         if ( $params ) {
1421                 call_user_func_array( [ $message, 'params' ], $params );
1422         }
1423
1424         return $message;
1425 }
1426
1427 /**
1428  * This function accepts multiple message keys and returns a message instance
1429  * for the first message which is non-empty. If all messages are empty then an
1430  * instance of the first message key is returned.
1431  *
1432  * @param string|string[] $keys,... Message keys
1433  * @return Message
1434  *
1435  * @since 1.18
1436  *
1437  * @see Message::newFallbackSequence
1438  */
1439 function wfMessageFallback( /*...*/ ) {
1440         $args = func_get_args();
1441         return call_user_func_array( 'Message::newFallbackSequence', $args );
1442 }
1443
1444 /**
1445  * Replace message parameter keys on the given formatted output.
1446  *
1447  * @param string $message
1448  * @param array $args
1449  * @return string
1450  * @private
1451  */
1452 function wfMsgReplaceArgs( $message, $args ) {
1453         # Fix windows line-endings
1454         # Some messages are split with explode("\n", $msg)
1455         $message = str_replace( "\r", '', $message );
1456
1457         // Replace arguments
1458         if ( is_array( $args ) && $args ) {
1459                 if ( is_array( $args[0] ) ) {
1460                         $args = array_values( $args[0] );
1461                 }
1462                 $replacementKeys = [];
1463                 foreach ( $args as $n => $param ) {
1464                         $replacementKeys['$' . ( $n + 1 )] = $param;
1465                 }
1466                 $message = strtr( $message, $replacementKeys );
1467         }
1468
1469         return $message;
1470 }
1471
1472 /**
1473  * Fetch server name for use in error reporting etc.
1474  * Use real server name if available, so we know which machine
1475  * in a server farm generated the current page.
1476  *
1477  * @return string
1478  */
1479 function wfHostname() {
1480         static $host;
1481         if ( is_null( $host ) ) {
1482                 # Hostname overriding
1483                 global $wgOverrideHostname;
1484                 if ( $wgOverrideHostname !== false ) {
1485                         # Set static and skip any detection
1486                         $host = $wgOverrideHostname;
1487                         return $host;
1488                 }
1489
1490                 if ( function_exists( 'posix_uname' ) ) {
1491                         // This function not present on Windows
1492                         $uname = posix_uname();
1493                 } else {
1494                         $uname = false;
1495                 }
1496                 if ( is_array( $uname ) && isset( $uname['nodename'] ) ) {
1497                         $host = $uname['nodename'];
1498                 } elseif ( getenv( 'COMPUTERNAME' ) ) {
1499                         # Windows computer name
1500                         $host = getenv( 'COMPUTERNAME' );
1501                 } else {
1502                         # This may be a virtual server.
1503                         $host = $_SERVER['SERVER_NAME'];
1504                 }
1505         }
1506         return $host;
1507 }
1508
1509 /**
1510  * Returns a script tag that stores the amount of time it took MediaWiki to
1511  * handle the request in milliseconds as 'wgBackendResponseTime'.
1512  *
1513  * If $wgShowHostnames is true, the script will also set 'wgHostname' to the
1514  * hostname of the server handling the request.
1515  *
1516  * @param string $nonce Value from OutputPage::getCSPNonce
1517  * @return string
1518  */
1519 function wfReportTime( $nonce = null ) {
1520         global $wgShowHostnames;
1521
1522         $elapsed = ( microtime( true ) - $_SERVER['REQUEST_TIME_FLOAT'] );
1523         // seconds to milliseconds
1524         $responseTime = round( $elapsed * 1000 );
1525         $reportVars = [ 'wgBackendResponseTime' => $responseTime ];
1526         if ( $wgShowHostnames ) {
1527                 $reportVars['wgHostname'] = wfHostname();
1528         }
1529         return Skin::makeVariablesScript( $reportVars, $nonce );
1530 }
1531
1532 /**
1533  * Safety wrapper for debug_backtrace().
1534  *
1535  * Will return an empty array if debug_backtrace is disabled, otherwise
1536  * the output from debug_backtrace() (trimmed).
1537  *
1538  * @param int $limit This parameter can be used to limit the number of stack frames returned
1539  *
1540  * @return array Array of backtrace information
1541  */
1542 function wfDebugBacktrace( $limit = 0 ) {
1543         static $disabled = null;
1544
1545         if ( is_null( $disabled ) ) {
1546                 $disabled = !function_exists( 'debug_backtrace' );
1547                 if ( $disabled ) {
1548                         wfDebug( "debug_backtrace() is disabled\n" );
1549                 }
1550         }
1551         if ( $disabled ) {
1552                 return [];
1553         }
1554
1555         if ( $limit ) {
1556                 return array_slice( debug_backtrace( DEBUG_BACKTRACE_PROVIDE_OBJECT, $limit + 1 ), 1 );
1557         } else {
1558                 return array_slice( debug_backtrace(), 1 );
1559         }
1560 }
1561
1562 /**
1563  * Get a debug backtrace as a string
1564  *
1565  * @param bool|null $raw If true, the return value is plain text. If false, HTML.
1566  *   Defaults to $wgCommandLineMode if unset.
1567  * @return string
1568  * @since 1.25 Supports $raw parameter.
1569  */
1570 function wfBacktrace( $raw = null ) {
1571         global $wgCommandLineMode;
1572
1573         if ( $raw === null ) {
1574                 $raw = $wgCommandLineMode;
1575         }
1576
1577         if ( $raw ) {
1578                 $frameFormat = "%s line %s calls %s()\n";
1579                 $traceFormat = "%s";
1580         } else {
1581                 $frameFormat = "<li>%s line %s calls %s()</li>\n";
1582                 $traceFormat = "<ul>\n%s</ul>\n";
1583         }
1584
1585         $frames = array_map( function ( $frame ) use ( $frameFormat ) {
1586                 $file = !empty( $frame['file'] ) ? basename( $frame['file'] ) : '-';
1587                 $line = isset( $frame['line'] ) ? $frame['line'] : '-';
1588                 $call = $frame['function'];
1589                 if ( !empty( $frame['class'] ) ) {
1590                         $call = $frame['class'] . $frame['type'] . $call;
1591                 }
1592                 return sprintf( $frameFormat, $file, $line, $call );
1593         }, wfDebugBacktrace() );
1594
1595         return sprintf( $traceFormat, implode( '', $frames ) );
1596 }
1597
1598 /**
1599  * Get the name of the function which called this function
1600  * wfGetCaller( 1 ) is the function with the wfGetCaller() call (ie. __FUNCTION__)
1601  * wfGetCaller( 2 ) [default] is the caller of the function running wfGetCaller()
1602  * wfGetCaller( 3 ) is the parent of that.
1603  *
1604  * @param int $level
1605  * @return string
1606  */
1607 function wfGetCaller( $level = 2 ) {
1608         $backtrace = wfDebugBacktrace( $level + 1 );
1609         if ( isset( $backtrace[$level] ) ) {
1610                 return wfFormatStackFrame( $backtrace[$level] );
1611         } else {
1612                 return 'unknown';
1613         }
1614 }
1615
1616 /**
1617  * Return a string consisting of callers in the stack. Useful sometimes
1618  * for profiling specific points.
1619  *
1620  * @param int $limit The maximum depth of the stack frame to return, or false for the entire stack.
1621  * @return string
1622  */
1623 function wfGetAllCallers( $limit = 3 ) {
1624         $trace = array_reverse( wfDebugBacktrace() );
1625         if ( !$limit || $limit > count( $trace ) - 1 ) {
1626                 $limit = count( $trace ) - 1;
1627         }
1628         $trace = array_slice( $trace, -$limit - 1, $limit );
1629         return implode( '/', array_map( 'wfFormatStackFrame', $trace ) );
1630 }
1631
1632 /**
1633  * Return a string representation of frame
1634  *
1635  * @param array $frame
1636  * @return string
1637  */
1638 function wfFormatStackFrame( $frame ) {
1639         if ( !isset( $frame['function'] ) ) {
1640                 return 'NO_FUNCTION_GIVEN';
1641         }
1642         return isset( $frame['class'] ) && isset( $frame['type'] ) ?
1643                 $frame['class'] . $frame['type'] . $frame['function'] :
1644                 $frame['function'];
1645 }
1646
1647 /* Some generic result counters, pulled out of SearchEngine */
1648
1649 /**
1650  * @todo document
1651  *
1652  * @param int $offset
1653  * @param int $limit
1654  * @return string
1655  */
1656 function wfShowingResults( $offset, $limit ) {
1657         return wfMessage( 'showingresults' )->numParams( $limit, $offset + 1 )->parse();
1658 }
1659
1660 /**
1661  * Whether the client accept gzip encoding
1662  *
1663  * Uses the Accept-Encoding header to check if the client supports gzip encoding.
1664  * Use this when considering to send a gzip-encoded response to the client.
1665  *
1666  * @param bool $force Forces another check even if we already have a cached result.
1667  * @return bool
1668  */
1669 function wfClientAcceptsGzip( $force = false ) {
1670         static $result = null;
1671         if ( $result === null || $force ) {
1672                 $result = false;
1673                 if ( isset( $_SERVER['HTTP_ACCEPT_ENCODING'] ) ) {
1674                         # @todo FIXME: We may want to blacklist some broken browsers
1675                         $m = [];
1676                         if ( preg_match(
1677                                         '/\bgzip(?:;(q)=([0-9]+(?:\.[0-9]+)))?\b/',
1678                                         $_SERVER['HTTP_ACCEPT_ENCODING'],
1679                                         $m
1680                                 )
1681                         ) {
1682                                 if ( isset( $m[2] ) && ( $m[1] == 'q' ) && ( $m[2] == 0 ) ) {
1683                                         $result = false;
1684                                         return $result;
1685                                 }
1686                                 wfDebug( "wfClientAcceptsGzip: client accepts gzip.\n" );
1687                                 $result = true;
1688                         }
1689                 }
1690         }
1691         return $result;
1692 }
1693
1694 /**
1695  * Escapes the given text so that it may be output using addWikiText()
1696  * without any linking, formatting, etc. making its way through. This
1697  * is achieved by substituting certain characters with HTML entities.
1698  * As required by the callers, "<nowiki>" is not used.
1699  *
1700  * @param string $text Text to be escaped
1701  * @return string
1702  */
1703 function wfEscapeWikiText( $text ) {
1704         global $wgEnableMagicLinks;
1705         static $repl = null, $repl2 = null;
1706         if ( $repl === null || defined( 'MW_PARSER_TEST' ) || defined( 'MW_PHPUNIT_TEST' ) ) {
1707                 // Tests depend upon being able to change $wgEnableMagicLinks, so don't cache
1708                 // in those situations
1709                 $repl = [
1710                         '"' => '&#34;', '&' => '&#38;', "'" => '&#39;', '<' => '&#60;',
1711                         '=' => '&#61;', '>' => '&#62;', '[' => '&#91;', ']' => '&#93;',
1712                         '{' => '&#123;', '|' => '&#124;', '}' => '&#125;', ';' => '&#59;',
1713                         "\n#" => "\n&#35;", "\r#" => "\r&#35;",
1714                         "\n*" => "\n&#42;", "\r*" => "\r&#42;",
1715                         "\n:" => "\n&#58;", "\r:" => "\r&#58;",
1716                         "\n " => "\n&#32;", "\r " => "\r&#32;",
1717                         "\n\n" => "\n&#10;", "\r\n" => "&#13;\n",
1718                         "\n\r" => "\n&#13;", "\r\r" => "\r&#13;",
1719                         "\n\t" => "\n&#9;", "\r\t" => "\r&#9;", // "\n\t\n" is treated like "\n\n"
1720                         "\n----" => "\n&#45;---", "\r----" => "\r&#45;---",
1721                         '__' => '_&#95;', '://' => '&#58;//',
1722                 ];
1723
1724                 $magicLinks = array_keys( array_filter( $wgEnableMagicLinks ) );
1725                 // We have to catch everything "\s" matches in PCRE
1726                 foreach ( $magicLinks as $magic ) {
1727                         $repl["$magic "] = "$magic&#32;";
1728                         $repl["$magic\t"] = "$magic&#9;";
1729                         $repl["$magic\r"] = "$magic&#13;";
1730                         $repl["$magic\n"] = "$magic&#10;";
1731                         $repl["$magic\f"] = "$magic&#12;";
1732                 }
1733
1734                 // And handle protocols that don't use "://"
1735                 global $wgUrlProtocols;
1736                 $repl2 = [];
1737                 foreach ( $wgUrlProtocols as $prot ) {
1738                         if ( substr( $prot, -1 ) === ':' ) {
1739                                 $repl2[] = preg_quote( substr( $prot, 0, -1 ), '/' );
1740                         }
1741                 }
1742                 $repl2 = $repl2 ? '/\b(' . implode( '|', $repl2 ) . '):/i' : '/^(?!)/';
1743         }
1744         $text = substr( strtr( "\n$text", $repl ), 1 );
1745         $text = preg_replace( $repl2, '$1&#58;', $text );
1746         return $text;
1747 }
1748
1749 /**
1750  * Sets dest to source and returns the original value of dest
1751  * If source is NULL, it just returns the value, it doesn't set the variable
1752  * If force is true, it will set the value even if source is NULL
1753  *
1754  * @param mixed &$dest
1755  * @param mixed $source
1756  * @param bool $force
1757  * @return mixed
1758  */
1759 function wfSetVar( &$dest, $source, $force = false ) {
1760         $temp = $dest;
1761         if ( !is_null( $source ) || $force ) {
1762                 $dest = $source;
1763         }
1764         return $temp;
1765 }
1766
1767 /**
1768  * As for wfSetVar except setting a bit
1769  *
1770  * @param int &$dest
1771  * @param int $bit
1772  * @param bool $state
1773  *
1774  * @return bool
1775  */
1776 function wfSetBit( &$dest, $bit, $state = true ) {
1777         $temp = (bool)( $dest & $bit );
1778         if ( !is_null( $state ) ) {
1779                 if ( $state ) {
1780                         $dest |= $bit;
1781                 } else {
1782                         $dest &= ~$bit;
1783                 }
1784         }
1785         return $temp;
1786 }
1787
1788 /**
1789  * A wrapper around the PHP function var_export().
1790  * Either print it or add it to the regular output ($wgOut).
1791  *
1792  * @param mixed $var A PHP variable to dump.
1793  */
1794 function wfVarDump( $var ) {
1795         global $wgOut;
1796         $s = str_replace( "\n", "<br />\n", var_export( $var, true ) . "\n" );
1797         if ( headers_sent() || !isset( $wgOut ) || !is_object( $wgOut ) ) {
1798                 print $s;
1799         } else {
1800                 $wgOut->addHTML( $s );
1801         }
1802 }
1803
1804 /**
1805  * Provide a simple HTTP error.
1806  *
1807  * @param int|string $code
1808  * @param string $label
1809  * @param string $desc
1810  */
1811 function wfHttpError( $code, $label, $desc ) {
1812         global $wgOut;
1813         HttpStatus::header( $code );
1814         if ( $wgOut ) {
1815                 $wgOut->disable();
1816                 $wgOut->sendCacheControl();
1817         }
1818
1819         MediaWiki\HeaderCallback::warnIfHeadersSent();
1820         header( 'Content-type: text/html; charset=utf-8' );
1821         print '<!DOCTYPE html>' .
1822                 '<html><head><title>' .
1823                 htmlspecialchars( $label ) .
1824                 '</title></head><body><h1>' .
1825                 htmlspecialchars( $label ) .
1826                 '</h1><p>' .
1827                 nl2br( htmlspecialchars( $desc ) ) .
1828                 "</p></body></html>\n";
1829 }
1830
1831 /**
1832  * Clear away any user-level output buffers, discarding contents.
1833  *
1834  * Suitable for 'starting afresh', for instance when streaming
1835  * relatively large amounts of data without buffering, or wanting to
1836  * output image files without ob_gzhandler's compression.
1837  *
1838  * The optional $resetGzipEncoding parameter controls suppression of
1839  * the Content-Encoding header sent by ob_gzhandler; by default it
1840  * is left. See comments for wfClearOutputBuffers() for why it would
1841  * be used.
1842  *
1843  * Note that some PHP configuration options may add output buffer
1844  * layers which cannot be removed; these are left in place.
1845  *
1846  * @param bool $resetGzipEncoding
1847  */
1848 function wfResetOutputBuffers( $resetGzipEncoding = true ) {
1849         if ( $resetGzipEncoding ) {
1850                 // Suppress Content-Encoding and Content-Length
1851                 // headers from OutputHandler::handle.
1852                 global $wgDisableOutputCompression;
1853                 $wgDisableOutputCompression = true;
1854         }
1855         while ( $status = ob_get_status() ) {
1856                 if ( isset( $status['flags'] ) ) {
1857                         $flags = PHP_OUTPUT_HANDLER_CLEANABLE | PHP_OUTPUT_HANDLER_REMOVABLE;
1858                         $deleteable = ( $status['flags'] & $flags ) === $flags;
1859                 } elseif ( isset( $status['del'] ) ) {
1860                         $deleteable = $status['del'];
1861                 } else {
1862                         // Guess that any PHP-internal setting can't be removed.
1863                         $deleteable = $status['type'] !== 0; /* PHP_OUTPUT_HANDLER_INTERNAL */
1864                 }
1865                 if ( !$deleteable ) {
1866                         // Give up, and hope the result doesn't break
1867                         // output behavior.
1868                         break;
1869                 }
1870                 if ( $status['name'] === 'MediaWikiTestCase::wfResetOutputBuffersBarrier' ) {
1871                         // Unit testing barrier to prevent this function from breaking PHPUnit.
1872                         break;
1873                 }
1874                 if ( !ob_end_clean() ) {
1875                         // Could not remove output buffer handler; abort now
1876                         // to avoid getting in some kind of infinite loop.
1877                         break;
1878                 }
1879                 if ( $resetGzipEncoding ) {
1880                         if ( $status['name'] == 'ob_gzhandler' ) {
1881                                 // Reset the 'Content-Encoding' field set by this handler
1882                                 // so we can start fresh.
1883                                 header_remove( 'Content-Encoding' );
1884                                 break;
1885                         }
1886                 }
1887         }
1888 }
1889
1890 /**
1891  * More legible than passing a 'false' parameter to wfResetOutputBuffers():
1892  *
1893  * Clear away output buffers, but keep the Content-Encoding header
1894  * produced by ob_gzhandler, if any.
1895  *
1896  * This should be used for HTTP 304 responses, where you need to
1897  * preserve the Content-Encoding header of the real result, but
1898  * also need to suppress the output of ob_gzhandler to keep to spec
1899  * and avoid breaking Firefox in rare cases where the headers and
1900  * body are broken over two packets.
1901  */
1902 function wfClearOutputBuffers() {
1903         wfResetOutputBuffers( false );
1904 }
1905
1906 /**
1907  * Converts an Accept-* header into an array mapping string values to quality
1908  * factors
1909  *
1910  * @param string $accept
1911  * @param string $def Default
1912  * @return float[] Associative array of string => float pairs
1913  */
1914 function wfAcceptToPrefs( $accept, $def = '*/*' ) {
1915         # No arg means accept anything (per HTTP spec)
1916         if ( !$accept ) {
1917                 return [ $def => 1.0 ];
1918         }
1919
1920         $prefs = [];
1921
1922         $parts = explode( ',', $accept );
1923
1924         foreach ( $parts as $part ) {
1925                 # @todo FIXME: Doesn't deal with params like 'text/html; level=1'
1926                 $values = explode( ';', trim( $part ) );
1927                 $match = [];
1928                 if ( count( $values ) == 1 ) {
1929                         $prefs[$values[0]] = 1.0;
1930                 } elseif ( preg_match( '/q\s*=\s*(\d*\.\d+)/', $values[1], $match ) ) {
1931                         $prefs[$values[0]] = floatval( $match[1] );
1932                 }
1933         }
1934
1935         return $prefs;
1936 }
1937
1938 /**
1939  * Checks if a given MIME type matches any of the keys in the given
1940  * array. Basic wildcards are accepted in the array keys.
1941  *
1942  * Returns the matching MIME type (or wildcard) if a match, otherwise
1943  * NULL if no match.
1944  *
1945  * @param string $type
1946  * @param array $avail
1947  * @return string
1948  * @private
1949  */
1950 function mimeTypeMatch( $type, $avail ) {
1951         if ( array_key_exists( $type, $avail ) ) {
1952                 return $type;
1953         } else {
1954                 $mainType = explode( '/', $type )[0];
1955                 if ( array_key_exists( "$mainType/*", $avail ) ) {
1956                         return "$mainType/*";
1957                 } elseif ( array_key_exists( '*/*', $avail ) ) {
1958                         return '*/*';
1959                 } else {
1960                         return null;
1961                 }
1962         }
1963 }
1964
1965 /**
1966  * Returns the 'best' match between a client's requested internet media types
1967  * and the server's list of available types. Each list should be an associative
1968  * array of type to preference (preference is a float between 0.0 and 1.0).
1969  * Wildcards in the types are acceptable.
1970  *
1971  * @param array $cprefs Client's acceptable type list
1972  * @param array $sprefs Server's offered types
1973  * @return string
1974  *
1975  * @todo FIXME: Doesn't handle params like 'text/plain; charset=UTF-8'
1976  * XXX: generalize to negotiate other stuff
1977  */
1978 function wfNegotiateType( $cprefs, $sprefs ) {
1979         $combine = [];
1980
1981         foreach ( array_keys( $sprefs ) as $type ) {
1982                 $subType = explode( '/', $type )[1];
1983                 if ( $subType != '*' ) {
1984                         $ckey = mimeTypeMatch( $type, $cprefs );
1985                         if ( $ckey ) {
1986                                 $combine[$type] = $sprefs[$type] * $cprefs[$ckey];
1987                         }
1988                 }
1989         }
1990
1991         foreach ( array_keys( $cprefs ) as $type ) {
1992                 $subType = explode( '/', $type )[1];
1993                 if ( $subType != '*' && !array_key_exists( $type, $sprefs ) ) {
1994                         $skey = mimeTypeMatch( $type, $sprefs );
1995                         if ( $skey ) {
1996                                 $combine[$type] = $sprefs[$skey] * $cprefs[$type];
1997                         }
1998                 }
1999         }
2000
2001         $bestq = 0;
2002         $besttype = null;
2003
2004         foreach ( array_keys( $combine ) as $type ) {
2005                 if ( $combine[$type] > $bestq ) {
2006                         $besttype = $type;
2007                         $bestq = $combine[$type];
2008                 }
2009         }
2010
2011         return $besttype;
2012 }
2013
2014 /**
2015  * Reference-counted warning suppression
2016  *
2017  * @deprecated since 1.26, use Wikimedia\suppressWarnings() directly
2018  * @param bool $end
2019  */
2020 function wfSuppressWarnings( $end = false ) {
2021         Wikimedia\suppressWarnings( $end );
2022 }
2023
2024 /**
2025  * @deprecated since 1.26, use Wikimedia\restoreWarnings() directly
2026  * Restore error level to previous value
2027  */
2028 function wfRestoreWarnings() {
2029         Wikimedia\restoreWarnings();
2030 }
2031
2032 /**
2033  * Get a timestamp string in one of various formats
2034  *
2035  * @param mixed $outputtype A timestamp in one of the supported formats, the
2036  *   function will autodetect which format is supplied and act accordingly.
2037  * @param mixed $ts Optional timestamp to convert, default 0 for the current time
2038  * @return string|bool String / false The same date in the format specified in $outputtype or false
2039  */
2040 function wfTimestamp( $outputtype = TS_UNIX, $ts = 0 ) {
2041         $ret = MWTimestamp::convert( $outputtype, $ts );
2042         if ( $ret === false ) {
2043                 wfDebug( "wfTimestamp() fed bogus time value: TYPE=$outputtype; VALUE=$ts\n" );
2044         }
2045         return $ret;
2046 }
2047
2048 /**
2049  * Return a formatted timestamp, or null if input is null.
2050  * For dealing with nullable timestamp columns in the database.
2051  *
2052  * @param int $outputtype
2053  * @param string $ts
2054  * @return string
2055  */
2056 function wfTimestampOrNull( $outputtype = TS_UNIX, $ts = null ) {
2057         if ( is_null( $ts ) ) {
2058                 return null;
2059         } else {
2060                 return wfTimestamp( $outputtype, $ts );
2061         }
2062 }
2063
2064 /**
2065  * Convenience function; returns MediaWiki timestamp for the present time.
2066  *
2067  * @return string
2068  */
2069 function wfTimestampNow() {
2070         # return NOW
2071         return MWTimestamp::now( TS_MW );
2072 }
2073
2074 /**
2075  * Check if the operating system is Windows
2076  *
2077  * @return bool True if it's Windows, false otherwise.
2078  */
2079 function wfIsWindows() {
2080         static $isWindows = null;
2081         if ( $isWindows === null ) {
2082                 $isWindows = strtoupper( substr( PHP_OS, 0, 3 ) ) === 'WIN';
2083         }
2084         return $isWindows;
2085 }
2086
2087 /**
2088  * Check if we are running under HHVM
2089  *
2090  * @return bool
2091  */
2092 function wfIsHHVM() {
2093         return defined( 'HHVM_VERSION' );
2094 }
2095
2096 /**
2097  * Check if we are running from the commandline
2098  *
2099  * @since 1.31
2100  * @return bool
2101  */
2102 function wfIsCLI() {
2103         return PHP_SAPI === 'cli' || PHP_SAPI === 'phpdbg';
2104 }
2105
2106 /**
2107  * Tries to get the system directory for temporary files. First
2108  * $wgTmpDirectory is checked, and then the TMPDIR, TMP, and TEMP
2109  * environment variables are then checked in sequence, then
2110  * sys_get_temp_dir(), then upload_tmp_dir from php.ini.
2111  *
2112  * NOTE: When possible, use instead the tmpfile() function to create
2113  * temporary files to avoid race conditions on file creation, etc.
2114  *
2115  * @return string
2116  */
2117 function wfTempDir() {
2118         global $wgTmpDirectory;
2119
2120         if ( $wgTmpDirectory !== false ) {
2121                 return $wgTmpDirectory;
2122         }
2123
2124         return TempFSFile::getUsableTempDirectory();
2125 }
2126
2127 /**
2128  * Make directory, and make all parent directories if they don't exist
2129  *
2130  * @param string $dir Full path to directory to create
2131  * @param int $mode Chmod value to use, default is $wgDirectoryMode
2132  * @param string $caller Optional caller param for debugging.
2133  * @throws MWException
2134  * @return bool
2135  */
2136 function wfMkdirParents( $dir, $mode = null, $caller = null ) {
2137         global $wgDirectoryMode;
2138
2139         if ( FileBackend::isStoragePath( $dir ) ) { // sanity
2140                 throw new MWException( __FUNCTION__ . " given storage path '$dir'." );
2141         }
2142
2143         if ( !is_null( $caller ) ) {
2144                 wfDebug( "$caller: called wfMkdirParents($dir)\n" );
2145         }
2146
2147         if ( strval( $dir ) === '' || is_dir( $dir ) ) {
2148                 return true;
2149         }
2150
2151         $dir = str_replace( [ '\\', '/' ], DIRECTORY_SEPARATOR, $dir );
2152
2153         if ( is_null( $mode ) ) {
2154                 $mode = $wgDirectoryMode;
2155         }
2156
2157         // Turn off the normal warning, we're doing our own below
2158         Wikimedia\suppressWarnings();
2159         $ok = mkdir( $dir, $mode, true ); // PHP5 <3
2160         Wikimedia\restoreWarnings();
2161
2162         if ( !$ok ) {
2163                 // directory may have been created on another request since we last checked
2164                 if ( is_dir( $dir ) ) {
2165                         return true;
2166                 }
2167
2168                 // PHP doesn't report the path in its warning message, so add our own to aid in diagnosis.
2169                 wfLogWarning( sprintf( "failed to mkdir \"%s\" mode 0%o", $dir, $mode ) );
2170         }
2171         return $ok;
2172 }
2173
2174 /**
2175  * Remove a directory and all its content.
2176  * Does not hide error.
2177  * @param string $dir
2178  */
2179 function wfRecursiveRemoveDir( $dir ) {
2180         wfDebug( __FUNCTION__ . "( $dir )\n" );
2181         // taken from https://secure.php.net/manual/en/function.rmdir.php#98622
2182         if ( is_dir( $dir ) ) {
2183                 $objects = scandir( $dir );
2184                 foreach ( $objects as $object ) {
2185                         if ( $object != "." && $object != ".." ) {
2186                                 if ( filetype( $dir . '/' . $object ) == "dir" ) {
2187                                         wfRecursiveRemoveDir( $dir . '/' . $object );
2188                                 } else {
2189                                         unlink( $dir . '/' . $object );
2190                                 }
2191                         }
2192                 }
2193                 reset( $objects );
2194                 rmdir( $dir );
2195         }
2196 }
2197
2198 /**
2199  * @param int $nr The number to format
2200  * @param int $acc The number of digits after the decimal point, default 2
2201  * @param bool $round Whether or not to round the value, default true
2202  * @return string
2203  */
2204 function wfPercent( $nr, $acc = 2, $round = true ) {
2205         $ret = sprintf( "%.${acc}f", $nr );
2206         return $round ? round( $ret, $acc ) . '%' : "$ret%";
2207 }
2208
2209 /**
2210  * Safety wrapper around ini_get() for boolean settings.
2211  * The values returned from ini_get() are pre-normalized for settings
2212  * set via php.ini or php_flag/php_admin_flag... but *not*
2213  * for those set via php_value/php_admin_value.
2214  *
2215  * It's fairly common for people to use php_value instead of php_flag,
2216  * which can leave you with an 'off' setting giving a false positive
2217  * for code that just takes the ini_get() return value as a boolean.
2218  *
2219  * To make things extra interesting, setting via php_value accepts
2220  * "true" and "yes" as true, but php.ini and php_flag consider them false. :)
2221  * Unrecognized values go false... again opposite PHP's own coercion
2222  * from string to bool.
2223  *
2224  * Luckily, 'properly' set settings will always come back as '0' or '1',
2225  * so we only have to worry about them and the 'improper' settings.
2226  *
2227  * I frickin' hate PHP... :P
2228  *
2229  * @param string $setting
2230  * @return bool
2231  */
2232 function wfIniGetBool( $setting ) {
2233         return wfStringToBool( ini_get( $setting ) );
2234 }
2235
2236 /**
2237  * Convert string value to boolean, when the following are interpreted as true:
2238  * - on
2239  * - true
2240  * - yes
2241  * - Any number, except 0
2242  * All other strings are interpreted as false.
2243  *
2244  * @param string $val
2245  * @return bool
2246  * @since 1.31
2247  */
2248 function wfStringToBool( $val ) {
2249         $val = strtolower( $val );
2250         // 'on' and 'true' can't have whitespace around them, but '1' can.
2251         return $val == 'on'
2252                 || $val == 'true'
2253                 || $val == 'yes'
2254                 || preg_match( "/^\s*[+-]?0*[1-9]/", $val ); // approx C atoi() function
2255 }
2256
2257 /**
2258  * Version of escapeshellarg() that works better on Windows.
2259  *
2260  * Originally, this fixed the incorrect use of single quotes on Windows
2261  * (https://bugs.php.net/bug.php?id=26285) and the locale problems on Linux in
2262  * PHP 5.2.6+ (bug backported to earlier distro releases of PHP).
2263  *
2264  * @param string $args,... strings to escape and glue together,
2265  *  or a single array of strings parameter
2266  * @return string
2267  * @deprecated since 1.30 use MediaWiki\Shell::escape()
2268  */
2269 function wfEscapeShellArg( /*...*/ ) {
2270         $args = func_get_args();
2271
2272         return call_user_func_array( Shell::class . '::escape', $args );
2273 }
2274
2275 /**
2276  * Execute a shell command, with time and memory limits mirrored from the PHP
2277  * configuration if supported.
2278  *
2279  * @param string|string[] $cmd If string, a properly shell-escaped command line,
2280  *   or an array of unescaped arguments, in which case each value will be escaped
2281  *   Example:   [ 'convert', '-font', 'font name' ] would produce "'convert' '-font' 'font name'"
2282  * @param null|mixed &$retval Optional, will receive the program's exit code.
2283  *   (non-zero is usually failure). If there is an error from
2284  *   read, select, or proc_open(), this will be set to -1.
2285  * @param array $environ Optional environment variables which should be
2286  *   added to the executed command environment.
2287  * @param array $limits Optional array with limits(filesize, memory, time, walltime)
2288  *   this overwrites the global wgMaxShell* limits.
2289  * @param array $options Array of options:
2290  *   - duplicateStderr: Set this to true to duplicate stderr to stdout,
2291  *     including errors from limit.sh
2292  *   - profileMethod: By default this function will profile based on the calling
2293  *     method. Set this to a string for an alternative method to profile from
2294  *
2295  * @return string Collected stdout as a string
2296  * @deprecated since 1.30 use class MediaWiki\Shell\Shell
2297  */
2298 function wfShellExec( $cmd, &$retval = null, $environ = [],
2299         $limits = [], $options = []
2300 ) {
2301         if ( Shell::isDisabled() ) {
2302                 $retval = 1;
2303                 // Backwards compatibility be upon us...
2304                 return 'Unable to run external programs, proc_open() is disabled.';
2305         }
2306
2307         if ( is_array( $cmd ) ) {
2308                 $cmd = Shell::escape( $cmd );
2309         }
2310
2311         $includeStderr = isset( $options['duplicateStderr'] ) && $options['duplicateStderr'];
2312         $profileMethod = isset( $options['profileMethod'] ) ? $options['profileMethod'] : wfGetCaller();
2313
2314         try {
2315                 $result = Shell::command( [] )
2316                         ->unsafeParams( (array)$cmd )
2317                         ->environment( $environ )
2318                         ->limits( $limits )
2319                         ->includeStderr( $includeStderr )
2320                         ->profileMethod( $profileMethod )
2321                         // For b/c
2322                         ->restrict( Shell::RESTRICT_NONE )
2323                         ->execute();
2324         } catch ( ProcOpenError $ex ) {
2325                 $retval = -1;
2326                 return '';
2327         }
2328
2329         $retval = $result->getExitCode();
2330
2331         return $result->getStdout();
2332 }
2333
2334 /**
2335  * Execute a shell command, returning both stdout and stderr. Convenience
2336  * function, as all the arguments to wfShellExec can become unwieldy.
2337  *
2338  * @note This also includes errors from limit.sh, e.g. if $wgMaxShellFileSize is exceeded.
2339  * @param string|string[] $cmd If string, a properly shell-escaped command line,
2340  *   or an array of unescaped arguments, in which case each value will be escaped
2341  *   Example:   [ 'convert', '-font', 'font name' ] would produce "'convert' '-font' 'font name'"
2342  * @param null|mixed &$retval Optional, will receive the program's exit code.
2343  *   (non-zero is usually failure)
2344  * @param array $environ Optional environment variables which should be
2345  *   added to the executed command environment.
2346  * @param array $limits Optional array with limits(filesize, memory, time, walltime)
2347  *   this overwrites the global wgMaxShell* limits.
2348  * @return string Collected stdout and stderr as a string
2349  * @deprecated since 1.30 use class MediaWiki\Shell\Shell
2350  */
2351 function wfShellExecWithStderr( $cmd, &$retval = null, $environ = [], $limits = [] ) {
2352         return wfShellExec( $cmd, $retval, $environ, $limits,
2353                 [ 'duplicateStderr' => true, 'profileMethod' => wfGetCaller() ] );
2354 }
2355
2356 /**
2357  * Generate a shell-escaped command line string to run a MediaWiki cli script.
2358  * Note that $parameters should be a flat array and an option with an argument
2359  * should consist of two consecutive items in the array (do not use "--option value").
2360  *
2361  * @deprecated since 1.31, use Shell::makeScriptCommand()
2362  *
2363  * @param string $script MediaWiki cli script path
2364  * @param array $parameters Arguments and options to the script
2365  * @param array $options Associative array of options:
2366  *     'php': The path to the php executable
2367  *     'wrapper': Path to a PHP wrapper to handle the maintenance script
2368  * @return string
2369  */
2370 function wfShellWikiCmd( $script, array $parameters = [], array $options = [] ) {
2371         global $wgPhpCli;
2372         // Give site config file a chance to run the script in a wrapper.
2373         // The caller may likely want to call wfBasename() on $script.
2374         Hooks::run( 'wfShellWikiCmd', [ &$script, &$parameters, &$options ] );
2375         $cmd = isset( $options['php'] ) ? [ $options['php'] ] : [ $wgPhpCli ];
2376         if ( isset( $options['wrapper'] ) ) {
2377                 $cmd[] = $options['wrapper'];
2378         }
2379         $cmd[] = $script;
2380         // Escape each parameter for shell
2381         return Shell::escape( array_merge( $cmd, $parameters ) );
2382 }
2383
2384 /**
2385  * wfMerge attempts to merge differences between three texts.
2386  * Returns true for a clean merge and false for failure or a conflict.
2387  *
2388  * @param string $old
2389  * @param string $mine
2390  * @param string $yours
2391  * @param string &$result
2392  * @param string &$mergeAttemptResult
2393  * @return bool
2394  */
2395 function wfMerge( $old, $mine, $yours, &$result, &$mergeAttemptResult = null ) {
2396         global $wgDiff3;
2397
2398         # This check may also protect against code injection in
2399         # case of broken installations.
2400         Wikimedia\suppressWarnings();
2401         $haveDiff3 = $wgDiff3 && file_exists( $wgDiff3 );
2402         Wikimedia\restoreWarnings();
2403
2404         if ( !$haveDiff3 ) {
2405                 wfDebug( "diff3 not found\n" );
2406                 return false;
2407         }
2408
2409         # Make temporary files
2410         $td = wfTempDir();
2411         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
2412         $mytextFile = fopen( $mytextName = tempnam( $td, 'merge-mine-' ), 'w' );
2413         $yourtextFile = fopen( $yourtextName = tempnam( $td, 'merge-your-' ), 'w' );
2414
2415         # NOTE: diff3 issues a warning to stderr if any of the files does not end with
2416         #       a newline character. To avoid this, we normalize the trailing whitespace before
2417         #       creating the diff.
2418
2419         fwrite( $oldtextFile, rtrim( $old ) . "\n" );
2420         fclose( $oldtextFile );
2421         fwrite( $mytextFile, rtrim( $mine ) . "\n" );
2422         fclose( $mytextFile );
2423         fwrite( $yourtextFile, rtrim( $yours ) . "\n" );
2424         fclose( $yourtextFile );
2425
2426         # Check for a conflict
2427         $cmd = Shell::escape( $wgDiff3, '-a', '--overlap-only', $mytextName,
2428                 $oldtextName, $yourtextName );
2429         $handle = popen( $cmd, 'r' );
2430
2431         $mergeAttemptResult = '';
2432         do {
2433                 $data = fread( $handle, 8192 );
2434                 if ( strlen( $data ) == 0 ) {
2435                         break;
2436                 }
2437                 $mergeAttemptResult .= $data;
2438         } while ( true );
2439         pclose( $handle );
2440
2441         $conflict = $mergeAttemptResult !== '';
2442
2443         # Merge differences
2444         $cmd = Shell::escape( $wgDiff3, '-a', '-e', '--merge', $mytextName,
2445                 $oldtextName, $yourtextName );
2446         $handle = popen( $cmd, 'r' );
2447         $result = '';
2448         do {
2449                 $data = fread( $handle, 8192 );
2450                 if ( strlen( $data ) == 0 ) {
2451                         break;
2452                 }
2453                 $result .= $data;
2454         } while ( true );
2455         pclose( $handle );
2456         unlink( $mytextName );
2457         unlink( $oldtextName );
2458         unlink( $yourtextName );
2459
2460         if ( $result === '' && $old !== '' && !$conflict ) {
2461                 wfDebug( "Unexpected null result from diff3. Command: $cmd\n" );
2462                 $conflict = true;
2463         }
2464         return !$conflict;
2465 }
2466
2467 /**
2468  * Returns unified plain-text diff of two texts.
2469  * "Useful" for machine processing of diffs.
2470  *
2471  * @deprecated since 1.25, use DiffEngine/UnifiedDiffFormatter directly
2472  *
2473  * @param string $before The text before the changes.
2474  * @param string $after The text after the changes.
2475  * @param string $params Command-line options for the diff command.
2476  * @return string Unified diff of $before and $after
2477  */
2478 function wfDiff( $before, $after, $params = '-u' ) {
2479         if ( $before == $after ) {
2480                 return '';
2481         }
2482
2483         global $wgDiff;
2484         Wikimedia\suppressWarnings();
2485         $haveDiff = $wgDiff && file_exists( $wgDiff );
2486         Wikimedia\restoreWarnings();
2487
2488         # This check may also protect against code injection in
2489         # case of broken installations.
2490         if ( !$haveDiff ) {
2491                 wfDebug( "diff executable not found\n" );
2492                 $diffs = new Diff( explode( "\n", $before ), explode( "\n", $after ) );
2493                 $format = new UnifiedDiffFormatter();
2494                 return $format->format( $diffs );
2495         }
2496
2497         # Make temporary files
2498         $td = wfTempDir();
2499         $oldtextFile = fopen( $oldtextName = tempnam( $td, 'merge-old-' ), 'w' );
2500         $newtextFile = fopen( $newtextName = tempnam( $td, 'merge-your-' ), 'w' );
2501
2502         fwrite( $oldtextFile, $before );
2503         fclose( $oldtextFile );
2504         fwrite( $newtextFile, $after );
2505         fclose( $newtextFile );
2506
2507         // Get the diff of the two files
2508         $cmd = "$wgDiff " . $params . ' ' . Shell::escape( $oldtextName, $newtextName );
2509
2510         $h = popen( $cmd, 'r' );
2511         if ( !$h ) {
2512                 unlink( $oldtextName );
2513                 unlink( $newtextName );
2514                 throw new Exception( __METHOD__ . '(): popen() failed' );
2515         }
2516
2517         $diff = '';
2518
2519         do {
2520                 $data = fread( $h, 8192 );
2521                 if ( strlen( $data ) == 0 ) {
2522                         break;
2523                 }
2524                 $diff .= $data;
2525         } while ( true );
2526
2527         // Clean up
2528         pclose( $h );
2529         unlink( $oldtextName );
2530         unlink( $newtextName );
2531
2532         // Kill the --- and +++ lines. They're not useful.
2533         $diff_lines = explode( "\n", $diff );
2534         if ( isset( $diff_lines[0] ) && strpos( $diff_lines[0], '---' ) === 0 ) {
2535                 unset( $diff_lines[0] );
2536         }
2537         if ( isset( $diff_lines[1] ) && strpos( $diff_lines[1], '+++' ) === 0 ) {
2538                 unset( $diff_lines[1] );
2539         }
2540
2541         $diff = implode( "\n", $diff_lines );
2542
2543         return $diff;
2544 }
2545
2546 /**
2547  * This function works like "use VERSION" in Perl, the program will die with a
2548  * backtrace if the current version of PHP is less than the version provided
2549  *
2550  * This is useful for extensions which due to their nature are not kept in sync
2551  * with releases, and might depend on other versions of PHP than the main code
2552  *
2553  * Note: PHP might die due to parsing errors in some cases before it ever
2554  *       manages to call this function, such is life
2555  *
2556  * @see perldoc -f use
2557  *
2558  * @param string|int|float $req_ver The version to check, can be a string, an integer, or a float
2559  *
2560  * @deprecated since 1.30
2561  *
2562  * @throws MWException
2563  */
2564 function wfUsePHP( $req_ver ) {
2565         wfDeprecated( __FUNCTION__, '1.30' );
2566         $php_ver = PHP_VERSION;
2567
2568         if ( version_compare( $php_ver, (string)$req_ver, '<' ) ) {
2569                 throw new MWException( "PHP $req_ver required--this is only $php_ver" );
2570         }
2571 }
2572
2573 /**
2574  * This function works like "use VERSION" in Perl except it checks the version
2575  * of MediaWiki, the program will die with a backtrace if the current version
2576  * of MediaWiki is less than the version provided.
2577  *
2578  * This is useful for extensions which due to their nature are not kept in sync
2579  * with releases
2580  *
2581  * Note: Due to the behavior of PHP's version_compare() which is used in this
2582  * function, if you want to allow the 'wmf' development versions add a 'c' (or
2583  * any single letter other than 'a', 'b' or 'p') as a post-fix to your
2584  * targeted version number. For example if you wanted to allow any variation
2585  * of 1.22 use `wfUseMW( '1.22c' )`. Using an 'a' or 'b' instead of 'c' will
2586  * not result in the same comparison due to the internal logic of
2587  * version_compare().
2588  *
2589  * @see perldoc -f use
2590  *
2591  * @deprecated since 1.26, use the "requires" property of extension.json
2592  * @param string|int|float $req_ver The version to check, can be a string, an integer, or a float
2593  * @throws MWException
2594  */
2595 function wfUseMW( $req_ver ) {
2596         global $wgVersion;
2597
2598         if ( version_compare( $wgVersion, (string)$req_ver, '<' ) ) {
2599                 throw new MWException( "MediaWiki $req_ver required--this is only $wgVersion" );
2600         }
2601 }
2602
2603 /**
2604  * Return the final portion of a pathname.
2605  * Reimplemented because PHP5's "basename()" is buggy with multibyte text.
2606  * https://bugs.php.net/bug.php?id=33898
2607  *
2608  * PHP's basename() only considers '\' a pathchar on Windows and Netware.
2609  * We'll consider it so always, as we don't want '\s' in our Unix paths either.
2610  *
2611  * @param string $path
2612  * @param string $suffix String to remove if present
2613  * @return string
2614  */
2615 function wfBaseName( $path, $suffix = '' ) {
2616         if ( $suffix == '' ) {
2617                 $encSuffix = '';
2618         } else {
2619                 $encSuffix = '(?:' . preg_quote( $suffix, '#' ) . ')?';
2620         }
2621
2622         $matches = [];
2623         if ( preg_match( "#([^/\\\\]*?){$encSuffix}[/\\\\]*$#", $path, $matches ) ) {
2624                 return $matches[1];
2625         } else {
2626                 return '';
2627         }
2628 }
2629
2630 /**
2631  * Generate a relative path name to the given file.
2632  * May explode on non-matching case-insensitive paths,
2633  * funky symlinks, etc.
2634  *
2635  * @param string $path Absolute destination path including target filename
2636  * @param string $from Absolute source path, directory only
2637  * @return string
2638  */
2639 function wfRelativePath( $path, $from ) {
2640         // Normalize mixed input on Windows...
2641         $path = str_replace( '/', DIRECTORY_SEPARATOR, $path );
2642         $from = str_replace( '/', DIRECTORY_SEPARATOR, $from );
2643
2644         // Trim trailing slashes -- fix for drive root
2645         $path = rtrim( $path, DIRECTORY_SEPARATOR );
2646         $from = rtrim( $from, DIRECTORY_SEPARATOR );
2647
2648         $pieces = explode( DIRECTORY_SEPARATOR, dirname( $path ) );
2649         $against = explode( DIRECTORY_SEPARATOR, $from );
2650
2651         if ( $pieces[0] !== $against[0] ) {
2652                 // Non-matching Windows drive letters?
2653                 // Return a full path.
2654                 return $path;
2655         }
2656
2657         // Trim off common prefix
2658         while ( count( $pieces ) && count( $against )
2659                 && $pieces[0] == $against[0] ) {
2660                 array_shift( $pieces );
2661                 array_shift( $against );
2662         }
2663
2664         // relative dots to bump us to the parent
2665         while ( count( $against ) ) {
2666                 array_unshift( $pieces, '..' );
2667                 array_shift( $against );
2668         }
2669
2670         array_push( $pieces, wfBaseName( $path ) );
2671
2672         return implode( DIRECTORY_SEPARATOR, $pieces );
2673 }
2674
2675 /**
2676  * Reset the session id
2677  *
2678  * @deprecated since 1.27, use MediaWiki\Session\SessionManager instead
2679  * @since 1.22
2680  */
2681 function wfResetSessionID() {
2682         wfDeprecated( __FUNCTION__, '1.27' );
2683         $session = SessionManager::getGlobalSession();
2684         $delay = $session->delaySave();
2685
2686         $session->resetId();
2687
2688         // Make sure a session is started, since that's what the old
2689         // wfResetSessionID() did.
2690         if ( session_id() !== $session->getId() ) {
2691                 wfSetupSession( $session->getId() );
2692         }
2693
2694         ScopedCallback::consume( $delay );
2695 }
2696
2697 /**
2698  * Initialise php session
2699  *
2700  * @deprecated since 1.27, use MediaWiki\Session\SessionManager instead.
2701  *  Generally, "using" SessionManager will be calling ->getSessionById() or
2702  *  ::getGlobalSession() (depending on whether you were passing $sessionId
2703  *  here), then calling $session->persist().
2704  * @param bool|string $sessionId
2705  */
2706 function wfSetupSession( $sessionId = false ) {
2707         wfDeprecated( __FUNCTION__, '1.27' );
2708
2709         if ( $sessionId ) {
2710                 session_id( $sessionId );
2711         }
2712
2713         $session = SessionManager::getGlobalSession();
2714         $session->persist();
2715
2716         if ( session_id() !== $session->getId() ) {
2717                 session_id( $session->getId() );
2718         }
2719         Wikimedia\quietCall( 'session_start' );
2720 }
2721
2722 /**
2723  * Get an object from the precompiled serialized directory
2724  *
2725  * @param string $name
2726  * @return mixed The variable on success, false on failure
2727  */
2728 function wfGetPrecompiledData( $name ) {
2729         global $IP;
2730
2731         $file = "$IP/serialized/$name";
2732         if ( file_exists( $file ) ) {
2733                 $blob = file_get_contents( $file );
2734                 if ( $blob ) {
2735                         return unserialize( $blob );
2736                 }
2737         }
2738         return false;
2739 }
2740
2741 /**
2742  * Make a cache key for the local wiki.
2743  *
2744  * @deprecated since 1.30 Call makeKey on a BagOStuff instance
2745  * @param string $args,...
2746  * @return string
2747  */
2748 function wfMemcKey( /*...*/ ) {
2749         return call_user_func_array(
2750                 [ ObjectCache::getLocalClusterInstance(), 'makeKey' ],
2751                 func_get_args()
2752         );
2753 }
2754
2755 /**
2756  * Make a cache key for a foreign DB.
2757  *
2758  * Must match what wfMemcKey() would produce in context of the foreign wiki.
2759  *
2760  * @param string $db
2761  * @param string $prefix
2762  * @param string $args,...
2763  * @return string
2764  */
2765 function wfForeignMemcKey( $db, $prefix /*...*/ ) {
2766         $args = array_slice( func_get_args(), 2 );
2767         $keyspace = $prefix ? "$db-$prefix" : $db;
2768         return call_user_func_array(
2769                 [ ObjectCache::getLocalClusterInstance(), 'makeKeyInternal' ],
2770                 [ $keyspace, $args ]
2771         );
2772 }
2773
2774 /**
2775  * Make a cache key with database-agnostic prefix.
2776  *
2777  * Doesn't have a wiki-specific namespace. Uses a generic 'global' prefix
2778  * instead. Must have a prefix as otherwise keys that use a database name
2779  * in the first segment will clash with wfMemcKey/wfForeignMemcKey.
2780  *
2781  * @deprecated since 1.30 Call makeGlobalKey on a BagOStuff instance
2782  * @since 1.26
2783  * @param string $args,...
2784  * @return string
2785  */
2786 function wfGlobalCacheKey( /*...*/ ) {
2787         return call_user_func_array(
2788                 [ ObjectCache::getLocalClusterInstance(), 'makeGlobalKey' ],
2789                 func_get_args()
2790         );
2791 }
2792
2793 /**
2794  * Get an ASCII string identifying this wiki
2795  * This is used as a prefix in memcached keys
2796  *
2797  * @return string
2798  */
2799 function wfWikiID() {
2800         global $wgDBprefix, $wgDBname;
2801         if ( $wgDBprefix ) {
2802                 return "$wgDBname-$wgDBprefix";
2803         } else {
2804                 return $wgDBname;
2805         }
2806 }
2807
2808 /**
2809  * Split a wiki ID into DB name and table prefix
2810  *
2811  * @param string $wiki
2812  *
2813  * @return array
2814  */
2815 function wfSplitWikiID( $wiki ) {
2816         $bits = explode( '-', $wiki, 2 );
2817         if ( count( $bits ) < 2 ) {
2818                 $bits[] = '';
2819         }
2820         return $bits;
2821 }
2822
2823 /**
2824  * Get a Database object.
2825  *
2826  * @param int $db Index of the connection to get. May be DB_MASTER for the
2827  *            master (for write queries), DB_REPLICA for potentially lagged read
2828  *            queries, or an integer >= 0 for a particular server.
2829  *
2830  * @param string|string[] $groups Query groups. An array of group names that this query
2831  *                belongs to. May contain a single string if the query is only
2832  *                in one group.
2833  *
2834  * @param string|bool $wiki The wiki ID, or false for the current wiki
2835  *
2836  * Note: multiple calls to wfGetDB(DB_REPLICA) during the course of one request
2837  * will always return the same object, unless the underlying connection or load
2838  * balancer is manually destroyed.
2839  *
2840  * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
2841  * updater to ensure that a proper database is being updated.
2842  *
2843  * @todo Replace calls to wfGetDB with calls to LoadBalancer::getConnection()
2844  *       on an injected instance of LoadBalancer.
2845  *
2846  * @return \Wikimedia\Rdbms\Database
2847  */
2848 function wfGetDB( $db, $groups = [], $wiki = false ) {
2849         return wfGetLB( $wiki )->getConnection( $db, $groups, $wiki );
2850 }
2851
2852 /**
2853  * Get a load balancer object.
2854  *
2855  * @deprecated since 1.27, use MediaWikiServices::getDBLoadBalancer()
2856  *              or MediaWikiServices::getDBLoadBalancerFactory() instead.
2857  *
2858  * @param string|bool $wiki Wiki ID, or false for the current wiki
2859  * @return \Wikimedia\Rdbms\LoadBalancer
2860  */
2861 function wfGetLB( $wiki = false ) {
2862         if ( $wiki === false ) {
2863                 return MediaWikiServices::getInstance()->getDBLoadBalancer();
2864         } else {
2865                 $factory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
2866                 return $factory->getMainLB( $wiki );
2867         }
2868 }
2869
2870 /**
2871  * Get the load balancer factory object
2872  *
2873  * @deprecated since 1.27, use MediaWikiServices::getDBLoadBalancerFactory() instead.
2874  *
2875  * @return \Wikimedia\Rdbms\LBFactory
2876  */
2877 function wfGetLBFactory() {
2878         return MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
2879 }
2880
2881 /**
2882  * Find a file.
2883  * Shortcut for RepoGroup::singleton()->findFile()
2884  *
2885  * @param string|Title $title String or Title object
2886  * @param array $options Associative array of options (see RepoGroup::findFile)
2887  * @return File|bool File, or false if the file does not exist
2888  */
2889 function wfFindFile( $title, $options = [] ) {
2890         return RepoGroup::singleton()->findFile( $title, $options );
2891 }
2892
2893 /**
2894  * Get an object referring to a locally registered file.
2895  * Returns a valid placeholder object if the file does not exist.
2896  *
2897  * @param Title|string $title
2898  * @return LocalFile|null A File, or null if passed an invalid Title
2899  */
2900 function wfLocalFile( $title ) {
2901         return RepoGroup::singleton()->getLocalRepo()->newFile( $title );
2902 }
2903
2904 /**
2905  * Should low-performance queries be disabled?
2906  *
2907  * @return bool
2908  * @codeCoverageIgnore
2909  */
2910 function wfQueriesMustScale() {
2911         global $wgMiserMode;
2912         return $wgMiserMode
2913                 || ( SiteStats::pages() > 100000
2914                 && SiteStats::edits() > 1000000
2915                 && SiteStats::users() > 10000 );
2916 }
2917
2918 /**
2919  * Get the path to a specified script file, respecting file
2920  * extensions; this is a wrapper around $wgScriptPath etc.
2921  * except for 'index' and 'load' which use $wgScript/$wgLoadScript
2922  *
2923  * @param string $script Script filename, sans extension
2924  * @return string
2925  */
2926 function wfScript( $script = 'index' ) {
2927         global $wgScriptPath, $wgScript, $wgLoadScript;
2928         if ( $script === 'index' ) {
2929                 return $wgScript;
2930         } elseif ( $script === 'load' ) {
2931                 return $wgLoadScript;
2932         } else {
2933                 return "{$wgScriptPath}/{$script}.php";
2934         }
2935 }
2936
2937 /**
2938  * Get the script URL.
2939  *
2940  * @return string Script URL
2941  */
2942 function wfGetScriptUrl() {
2943         if ( isset( $_SERVER['SCRIPT_NAME'] ) ) {
2944                 /* as it was called, minus the query string.
2945                  *
2946                  * Some sites use Apache rewrite rules to handle subdomains,
2947                  * and have PHP set up in a weird way that causes PHP_SELF
2948                  * to contain the rewritten URL instead of the one that the
2949                  * outside world sees.
2950                  *
2951                  * If in this mode, use SCRIPT_URL instead, which mod_rewrite
2952                  * provides containing the "before" URL.
2953                  */
2954                 return $_SERVER['SCRIPT_NAME'];
2955         } else {
2956                 return $_SERVER['URL'];
2957         }
2958 }
2959
2960 /**
2961  * Convenience function converts boolean values into "true"
2962  * or "false" (string) values
2963  *
2964  * @param bool $value
2965  * @return string
2966  */
2967 function wfBoolToStr( $value ) {
2968         return $value ? 'true' : 'false';
2969 }
2970
2971 /**
2972  * Get a platform-independent path to the null file, e.g. /dev/null
2973  *
2974  * @return string
2975  */
2976 function wfGetNull() {
2977         return wfIsWindows() ? 'NUL' : '/dev/null';
2978 }
2979
2980 /**
2981  * Waits for the replica DBs to catch up to the master position
2982  *
2983  * Use this when updating very large numbers of rows, as in maintenance scripts,
2984  * to avoid causing too much lag. Of course, this is a no-op if there are no replica DBs.
2985  *
2986  * By default this waits on the main DB cluster of the current wiki.
2987  * If $cluster is set to "*" it will wait on all DB clusters, including
2988  * external ones. If the lag being waiting on is caused by the code that
2989  * does this check, it makes since to use $ifWritesSince, particularly if
2990  * cluster is "*", to avoid excess overhead.
2991  *
2992  * Never call this function after a big DB write that is still in a transaction.
2993  * This only makes sense after the possible lag inducing changes were committed.
2994  *
2995  * @param float|null $ifWritesSince Only wait if writes were done since this UNIX timestamp
2996  * @param string|bool $wiki Wiki identifier accepted by wfGetLB
2997  * @param string|bool $cluster Cluster name accepted by LBFactory. Default: false.
2998  * @param int|null $timeout Max wait time. Default: 1 day (cli), ~10 seconds (web)
2999  * @return bool Success (able to connect and no timeouts reached)
3000  * @deprecated since 1.27 Use LBFactory::waitForReplication
3001  */
3002 function wfWaitForSlaves(
3003         $ifWritesSince = null, $wiki = false, $cluster = false, $timeout = null
3004 ) {
3005         if ( $timeout === null ) {
3006                 $timeout = wfIsCLI() ? 60 : 10;
3007         }
3008
3009         if ( $cluster === '*' ) {
3010                 $cluster = false;
3011                 $wiki = false;
3012         } elseif ( $wiki === false ) {
3013                 $wiki = wfWikiID();
3014         }
3015
3016         try {
3017                 $lbFactory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
3018                 $lbFactory->waitForReplication( [
3019                         'wiki' => $wiki,
3020                         'cluster' => $cluster,
3021                         'timeout' => $timeout,
3022                         // B/C: first argument used to be "max seconds of lag"; ignore such values
3023                         'ifWritesSince' => ( $ifWritesSince > 1e9 ) ? $ifWritesSince : null
3024                 ] );
3025         } catch ( DBReplicationWaitError $e ) {
3026                 return false;
3027         }
3028
3029         return true;
3030 }
3031
3032 /**
3033  * Count down from $seconds to zero on the terminal, with a one-second pause
3034  * between showing each number. For use in command-line scripts.
3035  *
3036  * @deprecated since 1.31, use Maintenance::countDown()
3037  *
3038  * @codeCoverageIgnore
3039  * @param int $seconds
3040  */
3041 function wfCountDown( $seconds ) {
3042         wfDeprecated( __FUNCTION__, '1.31' );
3043         for ( $i = $seconds; $i >= 0; $i-- ) {
3044                 if ( $i != $seconds ) {
3045                         echo str_repeat( "\x08", strlen( $i + 1 ) );
3046                 }
3047                 echo $i;
3048                 flush();
3049                 if ( $i ) {
3050                         sleep( 1 );
3051                 }
3052         }
3053         echo "\n";
3054 }
3055
3056 /**
3057  * Replace all invalid characters with '-'.
3058  * Additional characters can be defined in $wgIllegalFileChars (see T22489).
3059  * By default, $wgIllegalFileChars includes ':', '/', '\'.
3060  *
3061  * @param string $name Filename to process
3062  * @return string
3063  */
3064 function wfStripIllegalFilenameChars( $name ) {
3065         global $wgIllegalFileChars;
3066         $illegalFileChars = $wgIllegalFileChars ? "|[" . $wgIllegalFileChars . "]" : '';
3067         $name = preg_replace(
3068                 "/[^" . Title::legalChars() . "]" . $illegalFileChars . "/",
3069                 '-',
3070                 $name
3071         );
3072         // $wgIllegalFileChars may not include '/' and '\', so we still need to do this
3073         $name = wfBaseName( $name );
3074         return $name;
3075 }
3076
3077 /**
3078  * Set PHP's memory limit to the larger of php.ini or $wgMemoryLimit
3079  *
3080  * @return int Resulting value of the memory limit.
3081  */
3082 function wfMemoryLimit() {
3083         global $wgMemoryLimit;
3084         $memlimit = wfShorthandToInteger( ini_get( 'memory_limit' ) );
3085         if ( $memlimit != -1 ) {
3086                 $conflimit = wfShorthandToInteger( $wgMemoryLimit );
3087                 if ( $conflimit == -1 ) {
3088                         wfDebug( "Removing PHP's memory limit\n" );
3089                         Wikimedia\suppressWarnings();
3090                         ini_set( 'memory_limit', $conflimit );
3091                         Wikimedia\restoreWarnings();
3092                         return $conflimit;
3093                 } elseif ( $conflimit > $memlimit ) {
3094                         wfDebug( "Raising PHP's memory limit to $conflimit bytes\n" );
3095                         Wikimedia\suppressWarnings();
3096                         ini_set( 'memory_limit', $conflimit );
3097                         Wikimedia\restoreWarnings();
3098                         return $conflimit;
3099                 }
3100         }
3101         return $memlimit;
3102 }
3103
3104 /**
3105  * Set PHP's time limit to the larger of php.ini or $wgTransactionalTimeLimit
3106  *
3107  * @return int Prior time limit
3108  * @since 1.26
3109  */
3110 function wfTransactionalTimeLimit() {
3111         global $wgTransactionalTimeLimit;
3112
3113         $timeLimit = ini_get( 'max_execution_time' );
3114         // Note that CLI scripts use 0
3115         if ( $timeLimit > 0 && $wgTransactionalTimeLimit > $timeLimit ) {
3116                 set_time_limit( $wgTransactionalTimeLimit );
3117         }
3118
3119         ignore_user_abort( true ); // ignore client disconnects
3120
3121         return $timeLimit;
3122 }
3123
3124 /**
3125  * Converts shorthand byte notation to integer form
3126  *
3127  * @param string $string
3128  * @param int $default Returned if $string is empty
3129  * @return int
3130  */
3131 function wfShorthandToInteger( $string = '', $default = -1 ) {
3132         $string = trim( $string );
3133         if ( $string === '' ) {
3134                 return $default;
3135         }
3136         $last = $string[strlen( $string ) - 1];
3137         $val = intval( $string );
3138         switch ( $last ) {
3139                 case 'g':
3140                 case 'G':
3141                         $val *= 1024;
3142                         // break intentionally missing
3143                 case 'm':
3144                 case 'M':
3145                         $val *= 1024;
3146                         // break intentionally missing
3147                 case 'k':
3148                 case 'K':
3149                         $val *= 1024;
3150         }
3151
3152         return $val;
3153 }
3154
3155 /**
3156  * Get the normalised IETF language tag
3157  * See unit test for examples.
3158  * See mediawiki.language.bcp47 for the JavaScript implementation.
3159  *
3160  * @deprecated since 1.31, use LanguageCode::bcp47() directly.
3161  *
3162  * @param string $code The language code.
3163  * @return string The language code which complying with BCP 47 standards.
3164  */
3165 function wfBCP47( $code ) {
3166         return LanguageCode::bcp47( $code );
3167 }
3168
3169 /**
3170  * Get a specific cache object.
3171  *
3172  * @param int|string $cacheType A CACHE_* constants, or other key in $wgObjectCaches
3173  * @return BagOStuff
3174  */
3175 function wfGetCache( $cacheType ) {
3176         return ObjectCache::getInstance( $cacheType );
3177 }
3178
3179 /**
3180  * Get the main cache object
3181  *
3182  * @return BagOStuff
3183  */
3184 function wfGetMainCache() {
3185         global $wgMainCacheType;
3186         return ObjectCache::getInstance( $wgMainCacheType );
3187 }
3188
3189 /**
3190  * Get the cache object used by the message cache
3191  *
3192  * @return BagOStuff
3193  */
3194 function wfGetMessageCacheStorage() {
3195         global $wgMessageCacheType;
3196         return ObjectCache::getInstance( $wgMessageCacheType );
3197 }
3198
3199 /**
3200  * Get the cache object used by the parser cache
3201  *
3202  * @deprecated since 1.30, use MediaWikiServices::getParserCache()->getCacheStorage()
3203  * @return BagOStuff
3204  */
3205 function wfGetParserCacheStorage() {
3206         global $wgParserCacheType;
3207         return ObjectCache::getInstance( $wgParserCacheType );
3208 }
3209
3210 /**
3211  * Call hook functions defined in $wgHooks
3212  *
3213  * @param string $event Event name
3214  * @param array $args Parameters passed to hook functions
3215  * @param string|null $deprecatedVersion Optionally mark hook as deprecated with version number
3216  *
3217  * @return bool True if no handler aborted the hook
3218  * @deprecated since 1.25 - use Hooks::run
3219  */
3220 function wfRunHooks( $event, array $args = [], $deprecatedVersion = null ) {
3221         wfDeprecated( __METHOD__, '1.25' );
3222         return Hooks::run( $event, $args, $deprecatedVersion );
3223 }
3224
3225 /**
3226  * Wrapper around php's unpack.
3227  *
3228  * @param string $format The format string (See php's docs)
3229  * @param string $data A binary string of binary data
3230  * @param int|bool $length The minimum length of $data or false. This is to
3231  *      prevent reading beyond the end of $data. false to disable the check.
3232  *
3233  * Also be careful when using this function to read unsigned 32 bit integer
3234  * because php might make it negative.
3235  *
3236  * @throws MWException If $data not long enough, or if unpack fails
3237  * @return array Associative array of the extracted data
3238  */
3239 function wfUnpack( $format, $data, $length = false ) {
3240         if ( $length !== false ) {
3241                 $realLen = strlen( $data );
3242                 if ( $realLen < $length ) {
3243                         throw new MWException( "Tried to use wfUnpack on a "
3244                                 . "string of length $realLen, but needed one "
3245                                 . "of at least length $length."
3246                         );
3247                 }
3248         }
3249
3250         Wikimedia\suppressWarnings();
3251         $result = unpack( $format, $data );
3252         Wikimedia\restoreWarnings();
3253
3254         if ( $result === false ) {
3255                 // If it cannot extract the packed data.
3256                 throw new MWException( "unpack could not unpack binary data" );
3257         }
3258         return $result;
3259 }
3260
3261 /**
3262  * Determine if an image exists on the 'bad image list'.
3263  *
3264  * The format of MediaWiki:Bad_image_list is as follows:
3265  *    * Only list items (lines starting with "*") are considered
3266  *    * The first link on a line must be a link to a bad image
3267  *    * Any subsequent links on the same line are considered to be exceptions,
3268  *      i.e. articles where the image may occur inline.
3269  *
3270  * @param string $name The image name to check
3271  * @param Title|bool $contextTitle The page on which the image occurs, if known
3272  * @param string $blacklist Wikitext of a file blacklist
3273  * @return bool
3274  */
3275 function wfIsBadImage( $name, $contextTitle = false, $blacklist = null ) {
3276         # Handle redirects; callers almost always hit wfFindFile() anyway,
3277         # so just use that method because it has a fast process cache.
3278         $file = wfFindFile( $name ); // get the final name
3279         $name = $file ? $file->getTitle()->getDBkey() : $name;
3280
3281         # Run the extension hook
3282         $bad = false;
3283         if ( !Hooks::run( 'BadImage', [ $name, &$bad ] ) ) {
3284                 return (bool)$bad;
3285         }
3286
3287         $cache = ObjectCache::getLocalServerInstance( 'hash' );
3288         $key = $cache->makeKey(
3289                 'bad-image-list', ( $blacklist === null ) ? 'default' : md5( $blacklist )
3290         );
3291         $badImages = $cache->get( $key );
3292
3293         if ( $badImages === false ) { // cache miss
3294                 if ( $blacklist === null ) {
3295                         $blacklist = wfMessage( 'bad_image_list' )->inContentLanguage()->plain(); // site list
3296                 }
3297                 # Build the list now
3298                 $badImages = [];
3299                 $lines = explode( "\n", $blacklist );
3300                 foreach ( $lines as $line ) {
3301                         # List items only
3302                         if ( substr( $line, 0, 1 ) !== '*' ) {
3303                                 continue;
3304                         }
3305
3306                         # Find all links
3307                         $m = [];
3308                         if ( !preg_match_all( '/\[\[:?(.*?)\]\]/', $line, $m ) ) {
3309                                 continue;
3310                         }
3311
3312                         $exceptions = [];
3313                         $imageDBkey = false;
3314                         foreach ( $m[1] as $i => $titleText ) {
3315                                 $title = Title::newFromText( $titleText );
3316                                 if ( !is_null( $title ) ) {
3317                                         if ( $i == 0 ) {
3318                                                 $imageDBkey = $title->getDBkey();
3319                                         } else {
3320                                                 $exceptions[$title->getPrefixedDBkey()] = true;
3321                                         }
3322                                 }
3323                         }
3324
3325                         if ( $imageDBkey !== false ) {
3326                                 $badImages[$imageDBkey] = $exceptions;
3327                         }
3328                 }
3329                 $cache->set( $key, $badImages, 60 );
3330         }
3331
3332         $contextKey = $contextTitle ? $contextTitle->getPrefixedDBkey() : false;
3333         $bad = isset( $badImages[$name] ) && !isset( $badImages[$name][$contextKey] );
3334
3335         return $bad;
3336 }
3337
3338 /**
3339  * Determine whether the client at a given source IP is likely to be able to
3340  * access the wiki via HTTPS.
3341  *
3342  * @param string $ip The IPv4/6 address in the normal human-readable form
3343  * @return bool
3344  */
3345 function wfCanIPUseHTTPS( $ip ) {
3346         $canDo = true;
3347         Hooks::run( 'CanIPUseHTTPS', [ $ip, &$canDo ] );
3348         return !!$canDo;
3349 }
3350
3351 /**
3352  * Determine input string is represents as infinity
3353  *
3354  * @param string $str The string to determine
3355  * @return bool
3356  * @since 1.25
3357  */
3358 function wfIsInfinity( $str ) {
3359         // These are hardcoded elsewhere in MediaWiki (e.g. mediawiki.special.block.js).
3360         $infinityValues = [ 'infinite', 'indefinite', 'infinity', 'never' ];
3361         return in_array( $str, $infinityValues );
3362 }
3363
3364 /**
3365  * Returns true if these thumbnail parameters match one that MediaWiki
3366  * requests from file description pages and/or parser output.
3367  *
3368  * $params is considered non-standard if they involve a non-standard
3369  * width or any non-default parameters aside from width and page number.
3370  * The number of possible files with standard parameters is far less than
3371  * that of all combinations; rate-limiting for them can thus be more generious.
3372  *
3373  * @param File $file
3374  * @param array $params
3375  * @return bool
3376  * @since 1.24 Moved from thumb.php to GlobalFunctions in 1.25
3377  */
3378 function wfThumbIsStandard( File $file, array $params ) {
3379         global $wgThumbLimits, $wgImageLimits, $wgResponsiveImages;
3380
3381         $multipliers = [ 1 ];
3382         if ( $wgResponsiveImages ) {
3383                 // These available sizes are hardcoded currently elsewhere in MediaWiki.
3384                 // @see Linker::processResponsiveImages
3385                 $multipliers[] = 1.5;
3386                 $multipliers[] = 2;
3387         }
3388
3389         $handler = $file->getHandler();
3390         if ( !$handler || !isset( $params['width'] ) ) {
3391                 return false;
3392         }
3393
3394         $basicParams = [];
3395         if ( isset( $params['page'] ) ) {
3396                 $basicParams['page'] = $params['page'];
3397         }
3398
3399         $thumbLimits = [];
3400         $imageLimits = [];
3401         // Expand limits to account for multipliers
3402         foreach ( $multipliers as $multiplier ) {
3403                 $thumbLimits = array_merge( $thumbLimits, array_map(
3404                         function ( $width ) use ( $multiplier ) {
3405                                 return round( $width * $multiplier );
3406                         }, $wgThumbLimits )
3407                 );
3408                 $imageLimits = array_merge( $imageLimits, array_map(
3409                         function ( $pair ) use ( $multiplier ) {
3410                                 return [
3411                                         round( $pair[0] * $multiplier ),
3412                                         round( $pair[1] * $multiplier ),
3413                                 ];
3414                         }, $wgImageLimits )
3415                 );
3416         }
3417
3418         // Check if the width matches one of $wgThumbLimits
3419         if ( in_array( $params['width'], $thumbLimits ) ) {
3420                 $normalParams = $basicParams + [ 'width' => $params['width'] ];
3421                 // Append any default values to the map (e.g. "lossy", "lossless", ...)
3422                 $handler->normaliseParams( $file, $normalParams );
3423         } else {
3424                 // If not, then check if the width matchs one of $wgImageLimits
3425                 $match = false;
3426                 foreach ( $imageLimits as $pair ) {
3427                         $normalParams = $basicParams + [ 'width' => $pair[0], 'height' => $pair[1] ];
3428                         // Decide whether the thumbnail should be scaled on width or height.
3429                         // Also append any default values to the map (e.g. "lossy", "lossless", ...)
3430                         $handler->normaliseParams( $file, $normalParams );
3431                         // Check if this standard thumbnail size maps to the given width
3432                         if ( $normalParams['width'] == $params['width'] ) {
3433                                 $match = true;
3434                                 break;
3435                         }
3436                 }
3437                 if ( !$match ) {
3438                         return false; // not standard for description pages
3439                 }
3440         }
3441
3442         // Check that the given values for non-page, non-width, params are just defaults
3443         foreach ( $params as $key => $value ) {
3444                 if ( !isset( $normalParams[$key] ) || $normalParams[$key] != $value ) {
3445                         return false;
3446                 }
3447         }
3448
3449         return true;
3450 }
3451
3452 /**
3453  * Merges two (possibly) 2 dimensional arrays into the target array ($baseArray).
3454  *
3455  * Values that exist in both values will be combined with += (all values of the array
3456  * of $newValues will be added to the values of the array of $baseArray, while values,
3457  * that exists in both, the value of $baseArray will be used).
3458  *
3459  * @param array $baseArray The array where you want to add the values of $newValues to
3460  * @param array $newValues An array with new values
3461  * @return array The combined array
3462  * @since 1.26
3463  */
3464 function wfArrayPlus2d( array $baseArray, array $newValues ) {
3465         // First merge items that are in both arrays
3466         foreach ( $baseArray as $name => &$groupVal ) {
3467                 if ( isset( $newValues[$name] ) ) {
3468                         $groupVal += $newValues[$name];
3469                 }
3470         }
3471         // Now add items that didn't exist yet
3472         $baseArray += $newValues;
3473
3474         return $baseArray;
3475 }
3476
3477 /**
3478  * Get system resource usage of current request context.
3479  * Invokes the getrusage(2) system call, requesting RUSAGE_SELF if on PHP5
3480  * or RUSAGE_THREAD if on HHVM. Returns false if getrusage is not available.
3481  *
3482  * @since 1.24
3483  * @return array|bool Resource usage data or false if no data available.
3484  */
3485 function wfGetRusage() {
3486         if ( !function_exists( 'getrusage' ) ) {
3487                 return false;
3488         } elseif ( defined( 'HHVM_VERSION' ) && PHP_OS === 'Linux' ) {
3489                 return getrusage( 2 /* RUSAGE_THREAD */ );
3490         } else {
3491                 return getrusage( 0 /* RUSAGE_SELF */ );
3492         }
3493 }