includes/installer/Installer.php

   1 <?php
   2 /**
   3  * Base code for MediaWiki installer.
   4  *
   5  * @file
   6  * @ingroup Deployment
   7  */
   8
   9 /**
  10  * This documentation group collects source code files with deployment functionality.
  11  *
  12  * @defgroup Deployment Deployment
  13  */
  14
  15 /**
  16  * Base installer class.
  17  *
  18  * This class provides the base for installation and update functionality
  19  * for both MediaWiki core and extensions.
  20  *
  21  * @ingroup Deployment
  22  * @since 1.17
  23  */
  24 abstract class Installer {
  25
  26         /**
  27          * TODO: make protected?
  28          *
  29          * @var array
  30          */
  31         public $settings;
  32
  33         /**
  34          * Cached DB installer instances, access using getDBInstaller().
  35          *
  36          * @var array
  37          */
  38         protected $dbInstallers = array();
  39
  40         /**
  41          * Minimum memory size in MB.
  42          *
  43          * @var integer
  44          */
  45         protected $minMemorySize = 50;
  46
  47         /**
  48          * Cached Title, used by parse().
  49          *
  50          * @var Title
  51          */
  52         protected $parserTitle;
  53
  54         /**
  55          * Cached ParserOptions, used by parse().
  56          *
  57          * @var ParserOptions
  58          */
  59         protected $parserOptions;
  60
  61         /**
  62          * Known database types. These correspond to the class names <type>Installer,
  63          * and are also MediaWiki database types valid for $wgDBtype.
  64          *
  65          * To add a new type, create a <type>Installer class and a Database<type>
  66          * class, and add a config-type-<type> message to MessagesEn.php.
  67          *
  68          * @var array
  69          */
  70         protected static $dbTypes = array(
  71                 'mysql',
  72                 'postgres',
  73                 'oracle',
  74                 'sqlite',
  75         );
  76
  77         /**
  78          * A list of environment check methods called by doEnvironmentChecks().
  79          * These may output warnings using showMessage(), and/or abort the
  80          * installation process by returning false.
  81          *
  82          * @var array
  83          */
  84         protected $envChecks = array(
  85                 'envCheckMediaWikiVersion',
  86                 'envCheckDB',
  87                 'envCheckRegisterGlobals',
  88                 'envCheckBrokenXML',
  89                 'envCheckPHP531',
  90                 'envCheckMagicQuotes',
  91                 'envCheckMagicSybase',
  92                 'envCheckMbstring',
  93                 'envCheckZE1',
  94                 'envCheckSafeMode',
  95                 'envCheckXML',
  96                 'envCheckPCRE',
  97                 'envCheckMemory',
  98                 'envCheckCache',
  99                 'envCheckDiff3',
 100                 'envCheckGraphics',
 101                 'envCheckPath',
 102                 'envCheckExtension',
 103                 'envCheckShellLocale',
 104                 'envCheckUploadsDirectory',
 105                 'envCheckLibicu'
 106         );
 107
 108         /**
 109          * UI interface for displaying a short message
 110          * The parameters are like parameters to wfMsg().
 111          * The messages will be in wikitext format, which will be converted to an
 112          * output format such as HTML or text before being sent to the user.
 113          */
 114         public abstract function showMessage( $msg /*, ... */ );
 115
 116         /**
 117          * Constructor, always call this from child classes.
 118          */
 119         public function __construct() {
 120                 // Disable the i18n cache and LoadBalancer
 121                 Language::getLocalisationCache()->disableBackend();
 122                 LBFactory::disableBackend();
 123         }
 124
 125         /**
 126          * Get a list of known DB types.
 127          */
 128         public static function getDBTypes() {
 129                 return self::$dbTypes;
 130         }
 131
 132         /**
 133          * Do initial checks of the PHP environment. Set variables according to
 134          * the observed environment.
 135          *
 136          * It's possible that this may be called under the CLI SAPI, not the SAPI
 137          * that the wiki will primarily run under. In that case, the subclass should
 138          * initialise variables such as wgScriptPath, before calling this function.
 139          *
 140          * Under the web subclass, it can already be assumed that PHP 5+ is in use
 141          * and that sessions are working.
 142          *
 143          * @return boolean
 144          */
 145         public function doEnvironmentChecks() {
 146                 $this->showMessage( 'config-env-php', phpversion() );
 147
 148                 $good = true;
 149
 150                 foreach ( $this->envChecks as $check ) {
 151                         $status = $this->$check();
 152                         if ( $status === false ) {
 153                                 $good = false;
 154                         }
 155                 }
 156
 157                 $this->setVar( '_Environment', $good );
 158
 159                 if ( $good ) {
 160                         $this->showMessage( 'config-env-good' );
 161                 } else {
 162                         $this->showMessage( 'config-env-bad' );
 163                 }
 164
 165                 return $good;
 166         }
 167
 168         /**
 169          * Set a MW configuration variable, or internal installer configuration variable.
 170          *
 171          * @param $name String
 172          * @param $value Mixed
 173          */
 174         public function setVar( $name, $value ) {
 175                 $this->settings[$name] = $value;
 176         }
 177
 178         /**
 179          * Get an MW configuration variable, or internal installer configuration variable.
 180          * The defaults come from $GLOBALS (ultimately DefaultSettings.php).
 181          * Installer variables are typically prefixed by an underscore.
 182          *
 183          * @param $name String
 184          * @param $default Mixed
 185          *
 186          * @return mixed
 187          */
 188         public function getVar( $name, $default = null ) {
 189                 if ( !isset( $this->settings[$name] ) ) {
 190                         return $default;
 191                 } else {
 192                         return $this->settings[$name];
 193                 }
 194         }
 195
 196         /**
 197          * Get an instance of DatabaseInstaller for the specified DB type.
 198          *
 199          * @param $type Mixed: DB installer for which is needed, false to use default.
 200          *
 201          * @return DatabaseInstaller
 202          */
 203         public function getDBInstaller( $type = false ) {
 204                 if ( !$type ) {
 205                         $type = $this->getVar( 'wgDBtype' );
 206                 }
 207
 208                 $type = strtolower( $type );
 209
 210                 if ( !isset( $this->dbInstallers[$type] ) ) {
 211                         $class = ucfirst( $type ). 'Installer';
 212                         $this->dbInstallers[$type] = new $class( $this );
 213                 }
 214
 215                 return $this->dbInstallers[$type];
 216         }
 217
 218         /**
 219          * Determine if LocalSettings exists. If it does, return an appropriate
 220          * status for whether upgrading is enabled or not.
 221          *
 222          * @return Status
 223          */
 224         public function getLocalSettingsStatus() {
 225                 global $IP;
 226
 227                 $status = Status::newGood();
 228
 229                 wfSuppressWarnings();
 230                 $ls = file_exists( "$IP/LocalSettings.php" );
 231                 wfRestoreWarnings();
 232
 233                 if( $ls ) {
 234                         require( "$IP/includes/DefaultSettings.php" );
 235                         require_once( "$IP/LocalSettings.php" );
 236                         $vars = get_defined_vars();
 237                         if( isset( $vars['wgUpgradeKey'] ) && $vars['wgUpgradeKey'] ) {
 238                                 $status->warning( 'config-localsettings-upgrade' );
 239                                 $this->setVar( '_UpgradeKey', $vars['wgUpgradeKey' ] );
 240                         } else {
 241                                 $status->fatal( 'config-localsettings-noupgrade' );
 242                         }
 243                 }
 244
 245                 return $status;
 246         }
 247
 248         /**
 249          * Get a fake password for sending back to the user in HTML.
 250          * This is a security mechanism to avoid compromise of the password in the
 251          * event of session ID compromise.
 252          *
 253          * @param $realPassword String
 254          *
 255          * @return string
 256          */
 257         public function getFakePassword( $realPassword ) {
 258                 return str_repeat( '*', strlen( $realPassword ) );
 259         }
 260
 261         /**
 262          * Set a variable which stores a password, except if the new value is a
 263          * fake password in which case leave it as it is.
 264          *
 265          * @param $name String
 266          * @param $value Mixed
 267          */
 268         public function setPassword( $name, $value ) {
 269                 if ( !preg_match( '/^\*+$/', $value ) ) {
 270                         $this->setVar( $name, $value );
 271                 }
 272         }
 273
 274         /**
 275          * On POSIX systems return the primary group of the webserver we're running under.
 276          * On other systems just returns null.
 277          *
 278          * This is used to advice the user that he should chgrp his config/data/images directory as the
 279          * webserver user before he can install.
 280          *
 281          * Public because SqliteInstaller needs it, and doesn't subclass Installer.
 282          *
 283          * @return mixed
 284          */
 285         public static function maybeGetWebserverPrimaryGroup() {
 286                 if ( !function_exists( 'posix_getegid' ) || !function_exists( 'posix_getpwuid' ) ) {
 287                         # I don't know this, this isn't UNIX.
 288                         return null;
 289                 }
 290
 291                 # posix_getegid() *not* getmygid() because we want the group of the webserver,
 292                 # not whoever owns the current script.
 293                 $gid = posix_getegid();
 294                 $getpwuid = posix_getpwuid( $gid );
 295                 $group = $getpwuid['name'];
 296
 297                 return $group;
 298         }
 299
 300         /**
 301          * Convert wikitext $text to HTML.
 302          *
 303          * This is potentially error prone since many parser features require a complete
 304          * installed MW database. The solution is to just not use those features when you
 305          * write your messages. This appears to work well enough. Basic formatting and
 306          * external links work just fine.
 307          *
 308          * But in case a translator decides to throw in a #ifexist or internal link or
 309          * whatever, this function is guarded to catch the attempted DB access and to present
 310          * some fallback text.
 311          *
 312          * @param $text String
 313          * @param $lineStart Boolean
 314          * @return String
 315          */
 316         public function parse( $text, $lineStart = false ) {
 317                 global $wgParser;
 318
 319                 try {
 320                         $out = $wgParser->parse( $text, $this->parserTitle, $this->parserOptions, $lineStart );
 321                         $html = $out->getText();
 322                 } catch ( DBAccessError $e ) {
 323                         $html = '<!--DB access attempted during parse-->  ' . htmlspecialchars( $text );
 324
 325                         if ( !empty( $this->debug ) ) {
 326                                 $html .= "<!--\n" . $e->getTraceAsString() . "\n-->";
 327                         }
 328                 }
 329
 330                 return $html;
 331         }
 332
 333         /**
 334          * TODO: document
 335          *
 336          * @param $installer DatabaseInstaller
 337          *
 338          * @return Status
 339          */
 340         public function installTables( DatabaseInstaller &$installer ) {
 341                 $status = $installer->createTables();
 342
 343                 if( $status->isOK() ) {
 344                         LBFactory::enableBackend();
 345                 }
 346
 347                 return $status;
 348         }
 349
 350         /**
 351          * Exports all wg* variables stored by the installer into global scope.
 352          */
 353         public function exportVars() {
 354                 foreach ( $this->settings as $name => $value ) {
 355                         if ( substr( $name, 0, 2 ) == 'wg' ) {
 356                                 $GLOBALS[$name] = $value;
 357                         }
 358                 }
 359         }
 360
 361         /**
 362          * Check if we're installing the latest version.
 363          */
 364         protected function envCheckMediaWikiVersion() {
 365                 global $wgVersion;
 366
 367                 if( !$this->getVar( '_ExternalHTTP' ) ) {
 368                         $this->showMessage( 'config-env-latest-disabled' );
 369                         return;
 370                 }
 371
 372                 $repository = wfGetRepository();
 373                 $currentVersion = $repository->getLatestCoreVersion();
 374
 375                 if ( $currentVersion === false ) {
 376                         # For when the request is successful but there's e.g. some silly man in
 377                         # the middle firewall blocking us, e.g. one of those annoying airport ones
 378                         $this->showMessage( 'config-env-latest-can-not-check', $repository->getLocation() );
 379                         return;
 380                 }
 381
 382                 if( version_compare( $wgVersion, $currentVersion, '<' ) ) {
 383                         $this->showMessage( 'config-env-latest-old' );
 384                         // FIXME: this only works for the web installer!
 385                         $this->showHelpBox( 'config-env-latest-help', $wgVersion, $currentVersion );
 386                 } elseif( version_compare( $wgVersion, $currentVersion, '>' ) ) {
 387                         $this->showMessage( 'config-env-latest-new' );
 388                 } else {
 389                         $this->showMessage( 'config-env-latest-ok' );
 390                 }
 391         }
 392
 393         /**
 394          * Environment check for DB types.
 395          */
 396         protected function envCheckDB() {
 397                 global $wgLang;
 398
 399                 $compiledDBs = array();
 400                 $goodNames = array();
 401                 $allNames = array();
 402
 403                 foreach ( self::getDBTypes() as $name ) {
 404                         $db = $this->getDBInstaller( $name );
 405                         $readableName = wfMsg( 'config-type-' . $name );
 406
 407                         if ( $db->isCompiled() ) {
 408                                 $compiledDBs[] = $name;
 409                                 $goodNames[] = $readableName;
 410                         }
 411
 412                         $allNames[] = $readableName;
 413                 }
 414
 415                 $this->setVar( '_CompiledDBs', $compiledDBs );
 416
 417                 if ( !$compiledDBs ) {
 418                         $this->showMessage( 'config-no-db' );
 419                         // FIXME: this only works for the web installer!
 420                         $this->showHelpBox( 'config-no-db-help', $wgLang->commaList( $allNames ) );
 421                         return false;
 422                 }
 423
 424                 $this->showMessage( 'config-have-db', $wgLang->listToText( $goodNames ), count( $goodNames ) );
 425
 426                 // Check for FTS3 full-text search module
 427                 $sqlite = $this->getDBInstaller( 'sqlite' );
 428                 if ( $sqlite->isCompiled() ) {
 429                         $db = new DatabaseSqliteStandalone( ':memory:' );
 430                         $this->showMessage( $db->getFulltextSearchModule() == 'FTS3'
 431                                 ? 'config-have-fts3'
 432                                 : 'config-no-fts3'
 433                         );
 434                 }
 435         }
 436
 437         /**
 438          * Environment check for register_globals.
 439          */
 440         protected function envCheckRegisterGlobals() {
 441                 if( wfIniGetBool( "magic_quotes_runtime" ) ) {
 442                         $this->showMessage( 'config-register-globals' );
 443                 }
 444         }
 445
 446         /**
 447          * Some versions of libxml+PHP break < and > encoding horribly
 448          */
 449         protected function envCheckBrokenXML() {
 450                 $test = new PhpXmlBugTester();
 451                 if ( !$test->ok ) {
 452                         $this->showMessage( 'config-brokenlibxml' );
 453                         return false;
 454                 }
 455         }
 456
 457         /**
 458          * Test PHP (probably 5.3.1, but it could regress again) to make sure that
 459          * reference parameters to __call() are not converted to null
 460          */
 461         protected function envCheckPHP531() {
 462                 $test = new PhpRefCallBugTester;
 463                 $test->execute();
 464                 if ( !$test->ok ) {
 465                         $this->showMessage( 'config-using531' );
 466                         return false;
 467                 }
 468         }
 469
 470         /**
 471          * Environment check for magic_quotes_runtime.
 472          */
 473         protected function envCheckMagicQuotes() {
 474                 if( wfIniGetBool( "magic_quotes_runtime" ) ) {
 475                         $this->showMessage( 'config-magic-quotes-runtime' );
 476                         return false;
 477                 }
 478         }
 479
 480         /**
 481          * Environment check for magic_quotes_sybase.
 482          */
 483         protected function envCheckMagicSybase() {
 484                 if ( wfIniGetBool( 'magic_quotes_sybase' ) ) {
 485                         $this->showMessage( 'config-magic-quotes-sybase' );
 486                         return false;
 487                 }
 488         }
 489
 490         /**
 491          * Environment check for mbstring.func_overload.
 492          */
 493         protected function envCheckMbstring() {
 494                 if ( wfIniGetBool( 'mbstring.func_overload' ) ) {
 495                         $this->showMessage( 'config-mbstring' );
 496                         return false;
 497                 }
 498         }
 499
 500         /**
 501          * Environment check for zend.ze1_compatibility_mode.
 502          */
 503         protected function envCheckZE1() {
 504                 if ( wfIniGetBool( 'zend.ze1_compatibility_mode' ) ) {
 505                         $this->showMessage( 'config-ze1' );
 506                         return false;
 507                 }
 508         }
 509
 510         /**
 511          * Environment check for safe_mode.
 512          */
 513         protected function envCheckSafeMode() {
 514                 if ( wfIniGetBool( 'safe_mode' ) ) {
 515                         $this->setVar( '_SafeMode', true );
 516                         $this->showMessage( 'config-safe-mode' );
 517                 }
 518         }
 519
 520         /**
 521          * Environment check for the XML module.
 522          */
 523         protected function envCheckXML() {
 524                 if ( !function_exists( "utf8_encode" ) ) {
 525                         $this->showMessage( 'config-xml-bad' );
 526                         return false;
 527                 }
 528                 $this->showMessage( 'config-xml-good' );
 529         }
 530
 531         /**
 532          * Environment check for the PCRE module.
 533          */
 534         protected function envCheckPCRE() {
 535                 if ( !function_exists( 'preg_match' ) ) {
 536                         $this->showMessage( 'config-pcre' );
 537                         return false;
 538                 }
 539                 wfSuppressWarnings();
 540                 $regexd = preg_replace( '/[\x{0400}-\x{04FF}]/u', '', '-АБВГД-' );
 541                 wfRestoreWarnings();
 542                 if ( $regexd != '--' ) {
 543                         $this->showMessage( 'config-pcre-no-utf8' );
 544                         return false;
 545                 }
 546         }
 547
 548         /**
 549          * Environment check for available memory.
 550          */
 551         protected function envCheckMemory() {
 552                 $limit = ini_get( 'memory_limit' );
 553
 554                 if ( !$limit || $limit == -1 ) {
 555                         $this->showMessage( 'config-memory-none' );
 556                         return true;
 557                 }
 558
 559                 $n = intval( $limit );
 560
 561                 if( preg_match( '/^([0-9]+)[Mm]$/', trim( $limit ), $m ) ) {
 562                         $n = intval( $m[1] * ( 1024 * 1024 ) );
 563                 }
 564
 565                 if( $n < $this->minMemorySize * 1024 * 1024 ) {
 566                         $newLimit = "{$this->minMemorySize}M";
 567
 568                         if( ini_set( "memory_limit", $newLimit ) === false ) {
 569                                 $this->showMessage( 'config-memory-bad', $limit );
 570                         } else {
 571                                 $this->showMessage( 'config-memory-raised', $limit, $newLimit );
 572                                 $this->setVar( '_RaiseMemory', true );
 573                         }
 574                 } else {
 575                         $this->showMessage( 'config-memory-ok', $limit );
 576                 }
 577         }
 578
 579         /**
 580          * Environment check for compiled object cache types.
 581          */
 582         protected function envCheckCache() {
 583                 $caches = array();
 584
 585                 foreach ( $this->objectCaches as $name => $function ) {
 586                         if ( function_exists( $function ) ) {
 587                                 $caches[$name] = true;
 588                                 $this->showMessage( 'config-' . $name );
 589                         }
 590                 }
 591
 592                 if ( !$caches ) {
 593                         $this->showMessage( 'config-no-cache' );
 594                 }
 595
 596                 $this->setVar( '_Caches', $caches );
 597         }
 598
 599         /**
 600          * Search for GNU diff3.
 601          */
 602         protected function envCheckDiff3() {
 603                 $names = array( "gdiff3", "diff3", "diff3.exe" );
 604                 $versionInfo = array( '$1 --version 2>&1', 'GNU diffutils' );
 605
 606                 $diff3 = $this->locateExecutableInDefaultPaths( $names, $versionInfo );
 607
 608                 if ( $diff3 ) {
 609                         $this->showMessage( 'config-diff3-good', $diff3 );
 610                         $this->setVar( 'wgDiff3', $diff3 );
 611                 } else {
 612                         $this->setVar( 'wgDiff3', false );
 613                         $this->showMessage( 'config-diff3-bad' );
 614                 }
 615         }
 616
 617         /**
 618          * Environment check for ImageMagick and GD.
 619          */
 620         protected function envCheckGraphics() {
 621                 $names = array( wfIsWindows() ? 'convert.exe' : 'convert' );
 622                 $convert = $this->locateExecutableInDefaultPaths( $names, array( '$1 -version', 'ImageMagick' ) );
 623
 624                 if ( $convert ) {
 625                         $this->setVar( 'wgImageMagickConvertCommand', $convert );
 626                         $this->showMessage( 'config-imagemagick', $convert );
 627                         return true;
 628                 } elseif ( function_exists( 'imagejpeg' ) ) {
 629                         $this->showMessage( 'config-gd' );
 630                         return true;
 631                 } else {
 632                         $this->showMessage( 'no-scaling' );
 633                 }
 634         }
 635
 636         /**
 637          * Environment check for setting $IP and $wgScriptPath.
 638          */
 639         protected function envCheckPath() {
 640                 global $IP;
 641                 $IP = dirname( dirname( dirname( __FILE__ ) ) );
 642
 643                 $this->setVar( 'IP', $IP );
 644                 $this->showMessage( 'config-dir', $IP );
 645
 646                 // PHP_SELF isn't available sometimes, such as when PHP is CGI but
 647                 // cgi.fix_pathinfo is disabled. In that case, fall back to SCRIPT_NAME
 648                 // to get the path to the current script... hopefully it's reliable. SIGH
 649                 if ( !empty( $_SERVER['PHP_SELF'] ) ) {
 650                         $path = $_SERVER['PHP_SELF'];
 651                 } elseif ( !empty( $_SERVER['SCRIPT_NAME'] ) ) {
 652                         $path = $_SERVER['SCRIPT_NAME'];
 653                 } elseif ( $this->getVar( 'wgScriptPath' ) ) {
 654                         // Some kind soul has set it for us already (e.g. debconf)
 655                         return true;
 656                 } else {
 657                         $this->showMessage( 'config-no-uri' );
 658                         return false;
 659                 }
 660
 661                 $uri = preg_replace( '{^(.*)/config.*$}', '$1', $path );
 662                 $this->setVar( 'wgScriptPath', $uri );
 663                 $this->showMessage( 'config-uri', $uri );
 664         }
 665
 666         /**
 667          * Environment check for setting the preferred PHP file extension.
 668          */
 669         protected function envCheckExtension() {
 670                 // FIXME: detect this properly
 671                 if ( defined( 'MW_INSTALL_PHP5_EXT' ) ) {
 672                         $ext = 'php5';
 673                 } else {
 674                         $ext = 'php';
 675                 }
 676
 677                 $this->setVar( 'wgScriptExtension', ".$ext" );
 678                 $this->showMessage( 'config-file-extension', $ext );
 679         }
 680
 681         /**
 682          * TODO: document
 683          */
 684         protected function envCheckShellLocale() {
 685                 $os = php_uname( 's' );
 686                 $supported = array( 'Linux', 'SunOS', 'HP-UX', 'Darwin' ); # Tested these
 687
 688                 if ( !in_array( $os, $supported ) ) {
 689                         return true;
 690                 }
 691
 692                 # Get a list of available locales.
 693                 $ret = false;
 694                 $lines = wfShellExec( '/usr/bin/locale -a', $ret );
 695
 696                 if ( $ret ) {
 697                         return true;
 698                 }
 699
 700                 $lines = wfArrayMap( 'trim', explode( "\n", $lines ) );
 701                 $candidatesByLocale = array();
 702                 $candidatesByLang = array();
 703
 704                 foreach ( $lines as $line ) {
 705                         if ( $line === '' ) {
 706                                 continue;
 707                         }
 708
 709                         if ( !preg_match( '/^([a-zA-Z]+)(_[a-zA-Z]+|)\.(utf8|UTF-8)(@[a-zA-Z_]*|)$/i', $line, $m ) ) {
 710                                 continue;
 711                         }
 712
 713                         list( $all, $lang, $territory, $charset, $modifier ) = $m;
 714
 715                         $candidatesByLocale[$m[0]] = $m;
 716                         $candidatesByLang[$lang][] = $m;
 717                 }
 718
 719                 # Try the current value of LANG.
 720                 if ( isset( $candidatesByLocale[ getenv( 'LANG' ) ] ) ) {
 721                         $this->setVar( 'wgShellLocale', getenv( 'LANG' ) );
 722                         $this->showMessage( 'config-shell-locale', getenv( 'LANG' ) );
 723                         return true;
 724                 }
 725
 726                 # Try the most common ones.
 727                 $commonLocales = array( 'en_US.UTF-8', 'en_US.utf8', 'de_DE.UTF-8', 'de_DE.utf8' );
 728                 foreach ( $commonLocales as $commonLocale ) {
 729                         if ( isset( $candidatesByLocale[$commonLocale] ) ) {
 730                                 $this->setVar( 'wgShellLocale', $commonLocale );
 731                                 $this->showMessage( 'config-shell-locale', $commonLocale );
 732                                 return true;
 733                         }
 734                 }
 735
 736                 # Is there an available locale in the Wiki's language?
 737                 $wikiLang = $this->getVar( 'wgLanguageCode' );
 738
 739                 if ( isset( $candidatesByLang[$wikiLang] ) ) {
 740                         $m = reset( $candidatesByLang[$wikiLang] );
 741                         $this->setVar( 'wgShellLocale', $m[0] );
 742                         $this->showMessage( 'config-shell-locale', $m[0] );
 743                         return true;
 744                 }
 745
 746                 # Are there any at all?
 747                 if ( count( $candidatesByLocale ) ) {
 748                         $m = reset( $candidatesByLocale );
 749                         $this->setVar( 'wgShellLocale', $m[0] );
 750                         $this->showMessage( 'config-shell-locale', $m[0] );
 751                         return true;
 752                 }
 753
 754                 # Give up.
 755                 return true;
 756         }
 757
 758         /**
 759          * TODO: document
 760          */
 761         protected function envCheckUploadsDirectory() {
 762                 global $IP, $wgServer;
 763
 764                 $dir = $IP . '/images/';
 765                 $url = $wgServer . $this->getVar( 'wgScriptPath' ) . '/images/';
 766                 $safe = !$this->dirIsExecutable( $dir, $url );
 767
 768                 if ( $safe ) {
 769                         $this->showMessage( 'config-uploads-safe' );
 770                 } else {
 771                         $this->showMessage( 'config-uploads-not-safe', $dir );
 772                 }
 773         }
 774
 775         /**
 776          * Convert a hex string representing a Unicode code point to that code point.
 777          * @param $c String
 778          * @return string
 779          */
 780         protected function unicodeChar( $c ) {
 781                 $c = hexdec($c);
 782                 if ($c <= 0x7F) {
 783                         return chr($c);
 784                 } else if ($c <= 0x7FF) {
 785                         return chr(0xC0 | $c >> 6) . chr(0x80 | $c & 0x3F);
 786                 } else if ($c <= 0xFFFF) {
 787                         return chr(0xE0 | $c >> 12) . chr(0x80 | $c >> 6 & 0x3F)
 788                                 . chr(0x80 | $c & 0x3F);
 789                 } else if ($c <= 0x10FFFF) {
 790                         return chr(0xF0 | $c >> 18) . chr(0x80 | $c >> 12 & 0x3F)
 791                                 . chr(0x80 | $c >> 6 & 0x3F)
 792                                 . chr(0x80 | $c & 0x3F);
 793                 } else {
 794                         return false;
 795                 }
 796         }
 797
 798
 799         /**
 800          * Check the libicu version
 801          */
 802         protected function envCheckLibicu() {
 803                 $utf8 = function_exists( 'utf8_normalize' );
 804                 $intl = function_exists( 'normalizer_normalize' );
 805
 806                 /**
 807                  * This needs to be updated something that the latest libicu
 808                  * will properly normalize.  This normalization was found at
 809                  * http://www.unicode.org/versions/Unicode5.2.0/#Character_Additions
 810                  * Note that we use the hex representation to create the code
 811                  * points in order to avoid any Unicode-destroying during transit.
 812                  */
 813                 $not_normal_c = $this->unicodeChar("FA6C");
 814                 $normal_c = $this->unicodeChar("242EE");
 815
 816                 $useNormalizer = 'php';
 817                 $needsUpdate = false;
 818
 819                 /**
 820                  * We're going to prefer the pecl extension here unless
 821                  * utf8_normalize is more up to date.
 822                  */
 823                 if( $utf8 ) {
 824                         $useNormalizer = 'utf8';
 825                         $utf8 = utf8_normalize( $not_normal_c, UNORM_NFC );
 826                         if ( $utf8 !== $normal_c ) $needsUpdate = true;
 827                 }
 828                 if( $intl ) {
 829                         $useNormalizer = 'intl';
 830                         $intl = normalizer_normalize( $not_normal_c, Normalizer::FORM_C );
 831                         if ( $intl !== $normal_c ) $needsUpdate = true;
 832                 }
 833
 834                 // Uses messages 'config-unicode-using-php', 'config-unicode-using-utf8', 'config-unicode-using-intl'
 835                 if( $useNormalizer === 'php' ) {
 836                         $this->showMessage( 'config-unicode-pure-php-warning' );
 837                 } else {
 838                         $this->showMessage( 'config-unicode-using-' . $useNormalizer );
 839                         if( $needsUpdate ) {
 840                                 $this->showMessage( 'config-unicode-update-warning' );
 841                         }
 842                 }
 843         }
 844
 845         /**
 846          * Get an array of likely places we can find executables. Check a bunch
 847          * of known Unix-like defaults, as well as the PATH environment variable
 848          * (which should maybe make it work for Windows?)
 849          *
 850          * @return Array
 851          */
 852         protected static function getPossibleBinPaths() {
 853                 return array_merge(
 854                         array( '/usr/bin', '/usr/local/bin', '/opt/csw/bin',
 855                                 '/usr/gnu/bin', '/usr/sfw/bin', '/sw/bin', '/opt/local/bin' ),
 856                         explode( PATH_SEPARATOR, getenv( 'PATH' ) )
 857                 );
 858         }
 859
 860         /**
 861          * Search a path for any of the given executable names. Returns the
 862          * executable name if found. Also checks the version string returned
 863          * by each executable.
 864          *
 865          * Used only by environment checks.
 866          *
 867          * @param $path String: path to search
 868          * @param $names Array of executable names
 869          * @param $versionInfo Boolean false or array with two members:
 870          *               0 => Command to run for version check, with $1 for the full executable name
 871          *               1 => String to compare the output with
 872          *
 873          * If $versionInfo is not false, only executables with a version
 874          * matching $versionInfo[1] will be returned.
 875          */
 876         public static function locateExecutable( $path, $names, $versionInfo = false ) {
 877                 if ( !is_array( $names ) ) {
 878                         $names = array( $names );
 879                 }
 880
 881                 foreach ( $names as $name ) {
 882                         $command = $path . DIRECTORY_SEPARATOR . $name;
 883
 884                         wfSuppressWarnings();
 885                         $file_exists = file_exists( $command );
 886                         wfRestoreWarnings();
 887
 888                         if ( $file_exists ) {
 889                                 if ( !$versionInfo ) {
 890                                         return $command;
 891                                 }
 892
 893                                 $file = str_replace( '$1', wfEscapeShellArg( $command ), $versionInfo[0] );
 894                                 if ( strstr( wfShellExec( $file ), $versionInfo[1] ) !== false ) {
 895                                         return $command;
 896                                 }
 897                         }
 898                 }
 899                 return false;
 900         }
 901
 902         /**
 903          * Same as locateExecutable(), but checks in getPossibleBinPaths() by default
 904          * @see locateExecutable()
 905          */
 906         public static function locateExecutableInDefaultPaths( $names, $versionInfo = false ) {
 907                 foreach( self::getPossibleBinPaths() as $path ) {
 908                         $exe = self::locateExecutable( $path, $names, $versionInfo );
 909                         if( $exe !== false ) {
 910                                 return $exe;
 911                         }
 912                 }
 913                 return false;
 914         }
 915
 916         /**
 917          * Checks if scripts located in the given directory can be executed via the given URL.
 918          *
 919          * Used only by environment checks.
 920          */
 921         public function dirIsExecutable( $dir, $url ) {
 922                 $scriptTypes = array(
 923                         'php' => array(
 924                                 "<?php echo 'ex' . 'ec';",
 925                                 "#!/var/env php5\n<?php echo 'ex' . 'ec';",
 926                         ),
 927                 );
 928
 929                 // it would be good to check other popular languages here, but it'll be slow.
 930
 931                 wfSuppressWarnings();
 932
 933                 foreach ( $scriptTypes as $ext => $contents ) {
 934                         foreach ( $contents as $source ) {
 935                                 $file = 'exectest.' . $ext;
 936
 937                                 if ( !file_put_contents( $dir . $file, $source ) ) {
 938                                         break;
 939                                 }
 940
 941                                 $text = Http::get( $url . $file );
 942                                 unlink( $dir . $file );
 943
 944                                 if ( $text == 'exec' ) {
 945                                         wfRestoreWarnings();
 946                                         return $ext;
 947                                 }
 948                         }
 949                 }
 950
 951                 wfRestoreWarnings();
 952
 953                 return false;
 954         }
 955
 956 }