includes/filerepo/backend/FSFileBackend.php

   1 <?php
   2 /**
   3  * @file
   4  * @ingroup FileBackend
   5  * @author Aaron Schulz
   6  */
   7
   8 /**
   9  * Class for a file system (FS) based file backend.
  10  *
  11  * All "containers" each map to a directory under the backend's base directory.
  12  * For backwards-compatibility, some container paths can be set to custom paths.
  13  * The wiki ID will not be used in any custom paths, so this should be avoided.
  14  *
  15  * Having directories with thousands of files will diminish performance.
  16  * Sharding can be accomplished by using FileRepo-style hash paths.
  17  *
  18  * Status messages should avoid mentioning the internal FS paths.
  19  * Likewise, error suppression should be used to avoid path disclosure.
  20  *
  21  * @ingroup FileBackend
  22  * @since 1.19
  23  */
  24 class FSFileBackend extends FileBackend {
  25         protected $basePath; // string; directory holding the container directories
  26         /** @var Array Map of container names to root paths */
  27         protected $containerPaths = array(); // for custom container paths
  28         protected $fileMode; // integer; file permission mode
  29
  30         protected $hadWarningErrors = array();
  31
  32         /**
  33          * @see FileBackend::__construct()
  34          * Additional $config params include:
  35          *    basePath       : File system directory that holds containers.
  36          *    containerPaths : Map of container names to custom file system directories.
  37          *                     This should only be used for backwards-compatibility.
  38          *    fileMode       : Octal UNIX file permissions to use on files stored.
  39          */
  40         public function __construct( array $config ) {
  41                 parent::__construct( $config );
  42                 if ( isset( $config['basePath'] ) ) {
  43                         if ( substr( $this->basePath, -1 ) === '/' ) {
  44                                 $this->basePath = substr( $this->basePath, 0, -1 ); // remove trailing slash
  45                         }
  46                 } else {
  47                         $this->basePath = null; // none; containers must have explicit paths
  48                 }
  49                 $this->containerPaths = (array)$config['containerPaths'];
  50                 foreach ( $this->containerPaths as &$path ) {
  51                         if ( substr( $path, -1 ) === '/' ) {
  52                                 $path = substr( $path, 0, -1 ); // remove trailing slash
  53                         }
  54                 }
  55                 $this->fileMode = isset( $config['fileMode'] )
  56                         ? $config['fileMode']
  57                         : 0644;
  58         }
  59
  60         /**
  61          * @see FileBackend::resolveContainerPath()
  62          */
  63         protected function resolveContainerPath( $container, $relStoragePath ) {
  64                 if ( isset( $this->containerPaths[$container] ) || isset( $this->basePath ) ) {
  65                         return $relStoragePath; // container has a root directory
  66                 }
  67                 return null;
  68         }
  69
  70         /**
  71          * Given the short (unresolved) and full (resolved) name of
  72          * a container, return the file system path of the container.
  73          *
  74          * @param $shortCont string
  75          * @param $fullCont string
  76          * @return string|null
  77          */
  78         protected function containerFSRoot( $shortCont, $fullCont ) {
  79                 if ( isset( $this->containerPaths[$shortCont] ) ) {
  80                         return $this->containerPaths[$shortCont];
  81                 } elseif ( isset( $this->basePath ) ) {
  82                         return "{$this->basePath}/{$fullCont}";
  83                 }
  84                 return null; // no container base path defined
  85         }
  86
  87         /**
  88          * Get the absolute file system path for a storage path
  89          *
  90          * @param $storagePath string Storage path
  91          * @return string|null
  92          */
  93         protected function resolveToFSPath( $storagePath ) {
  94                 list( $fullCont, $relPath ) = $this->resolveStoragePathReal( $storagePath );
  95                 if ( $relPath === null ) {
  96                         return null; // invalid
  97                 }
  98                 list( $b, $shortCont, $r ) = FileBackend::splitStoragePath( $storagePath );
  99                 $fsPath = $this->containerFSRoot( $shortCont, $fullCont ); // must be valid
 100                 if ( $relPath != '' ) {
 101                         $fsPath .= "/{$relPath}";
 102                 }
 103                 return $fsPath;
 104         }
 105
 106         /**
 107          * @see FileBackend::isPathUsableInternal()
 108          */
 109         public function isPathUsableInternal( $storagePath ) {
 110                 $fsPath = $this->resolveToFSPath( $storagePath );
 111                 if ( $fsPath === null ) {
 112                         return false; // invalid
 113                 }
 114                 $parentDir = dirname( $fsPath );
 115
 116                 wfSuppressWarnings();
 117                 if ( file_exists( $fsPath ) ) {
 118                         $ok = is_file( $fsPath ) && is_writable( $fsPath );
 119                 } else {
 120                         $ok = is_dir( $parentDir ) && is_writable( $parentDir );
 121                 }
 122                 wfRestoreWarnings();
 123
 124                 return $ok;
 125         }
 126
 127         /**
 128          * @see FileBackend::doStoreInternal()
 129          */
 130         protected function doStoreInternal( array $params ) {
 131                 $status = Status::newGood();
 132
 133                 $dest = $this->resolveToFSPath( $params['dst'] );
 134                 if ( $dest === null ) {
 135                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 136                         return $status;
 137                 }
 138
 139                 if ( file_exists( $dest ) ) {
 140                         if ( !empty( $params['overwrite'] ) ) {
 141                                 wfSuppressWarnings();
 142                                 $ok = unlink( $dest );
 143                                 wfRestoreWarnings();
 144                                 if ( !$ok ) {
 145                                         $status->fatal( 'backend-fail-delete', $params['dst'] );
 146                                         return $status;
 147                                 }
 148                         } else {
 149                                 $status->fatal( 'backend-fail-alreadyexists', $params['dst'] );
 150                                 return $status;
 151                         }
 152                 }
 153
 154                 wfSuppressWarnings();
 155                 $ok = copy( $params['src'], $dest );
 156                 wfRestoreWarnings();
 157                 if ( !$ok ) {
 158                         $status->fatal( 'backend-fail-store', $params['src'], $params['dst'] );
 159                         return $status;
 160                 }
 161
 162                 $this->chmod( $dest );
 163
 164                 return $status;
 165         }
 166
 167         /**
 168          * @see FileBackend::doCopyInternal()
 169          */
 170         protected function doCopyInternal( array $params ) {
 171                 $status = Status::newGood();
 172
 173                 $source = $this->resolveToFSPath( $params['src'] );
 174                 if ( $source === null ) {
 175                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 176                         return $status;
 177                 }
 178
 179                 $dest = $this->resolveToFSPath( $params['dst'] );
 180                 if ( $dest === null ) {
 181                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 182                         return $status;
 183                 }
 184
 185                 if ( file_exists( $dest ) ) {
 186                         if ( !empty( $params['overwrite'] ) ) {
 187                                 wfSuppressWarnings();
 188                                 $ok = unlink( $dest );
 189                                 wfRestoreWarnings();
 190                                 if ( !$ok ) {
 191                                         $status->fatal( 'backend-fail-delete', $params['dst'] );
 192                                         return $status;
 193                                 }
 194                         } else {
 195                                 $status->fatal( 'backend-fail-alreadyexists', $params['dst'] );
 196                                 return $status;
 197                         }
 198                 }
 199
 200                 wfSuppressWarnings();
 201                 $ok = copy( $source, $dest );
 202                 wfRestoreWarnings();
 203                 if ( !$ok ) {
 204                         $status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
 205                         return $status;
 206                 }
 207
 208                 $this->chmod( $dest );
 209
 210                 return $status;
 211         }
 212
 213         /**
 214          * @see FileBackend::doMoveInternal()
 215          */
 216         protected function doMoveInternal( array $params ) {
 217                 $status = Status::newGood();
 218
 219                 $source = $this->resolveToFSPath( $params['src'] );
 220                 if ( $source === null ) {
 221                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 222                         return $status;
 223                 }
 224
 225                 $dest = $this->resolveToFSPath( $params['dst'] );
 226                 if ( $dest === null ) {
 227                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 228                         return $status;
 229                 }
 230
 231                 if ( file_exists( $dest ) ) {
 232                         if ( !empty( $params['overwrite'] ) ) {
 233                                 // Windows does not support moving over existing files
 234                                 if ( wfIsWindows() ) {
 235                                         wfSuppressWarnings();
 236                                         $ok = unlink( $dest );
 237                                         wfRestoreWarnings();
 238                                         if ( !$ok ) {
 239                                                 $status->fatal( 'backend-fail-delete', $params['dst'] );
 240                                                 return $status;
 241                                         }
 242                                 }
 243                         } else {
 244                                 $status->fatal( 'backend-fail-alreadyexists', $params['dst'] );
 245                                 return $status;
 246                         }
 247                 }
 248
 249                 wfSuppressWarnings();
 250                 $ok = rename( $source, $dest );
 251                 clearstatcache(); // file no longer at source
 252                 wfRestoreWarnings();
 253                 if ( !$ok ) {
 254                         $status->fatal( 'backend-fail-move', $params['src'], $params['dst'] );
 255                         return $status;
 256                 }
 257
 258                 return $status;
 259         }
 260
 261         /**
 262          * @see FileBackend::doDeleteInternal()
 263          */
 264         protected function doDeleteInternal( array $params ) {
 265                 $status = Status::newGood();
 266
 267                 $source = $this->resolveToFSPath( $params['src'] );
 268                 if ( $source === null ) {
 269                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 270                         return $status;
 271                 }
 272
 273                 if ( !is_file( $source ) ) {
 274                         if ( empty( $params['ignoreMissingSource'] ) ) {
 275                                 $status->fatal( 'backend-fail-delete', $params['src'] );
 276                         }
 277                         return $status; // do nothing; either OK or bad status
 278                 }
 279
 280                 wfSuppressWarnings();
 281                 $ok = unlink( $source );
 282                 wfRestoreWarnings();
 283                 if ( !$ok ) {
 284                         $status->fatal( 'backend-fail-delete', $params['src'] );
 285                         return $status;
 286                 }
 287
 288                 return $status;
 289         }
 290
 291         /**
 292          * @see FileBackend::doCreateInternal()
 293          */
 294         protected function doCreateInternal( array $params ) {
 295                 $status = Status::newGood();
 296
 297                 $dest = $this->resolveToFSPath( $params['dst'] );
 298                 if ( $dest === null ) {
 299                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 300                         return $status;
 301                 }
 302
 303                 if ( file_exists( $dest ) ) {
 304                         if ( !empty( $params['overwrite'] ) ) {
 305                                 wfSuppressWarnings();
 306                                 $ok = unlink( $dest );
 307                                 wfRestoreWarnings();
 308                                 if ( !$ok ) {
 309                                         $status->fatal( 'backend-fail-delete', $params['dst'] );
 310                                         return $status;
 311                                 }
 312                         } else {
 313                                 $status->fatal( 'backend-fail-alreadyexists', $params['dst'] );
 314                                 return $status;
 315                         }
 316                 }
 317
 318                 wfSuppressWarnings();
 319                 $ok = file_put_contents( $dest, $params['content'] );
 320                 wfRestoreWarnings();
 321                 if ( !$ok ) {
 322                         $status->fatal( 'backend-fail-create', $params['dst'] );
 323                         return $status;
 324                 }
 325
 326                 $this->chmod( $dest );
 327
 328                 return $status;
 329         }
 330
 331         /**
 332          * @see FileBackend::doPrepareInternal()
 333          */
 334         protected function doPrepareInternal( $fullCont, $dirRel, array $params ) {
 335                 $status = Status::newGood();
 336                 list( $b, $shortCont, $r ) = FileBackend::splitStoragePath( $params['dir'] );
 337                 $contRoot = $this->containerFSRoot( $shortCont, $fullCont ); // must be valid
 338                 $dir = ( $dirRel != '' ) ? "{$contRoot}/{$dirRel}" : $contRoot;
 339                 if ( !wfMkdirParents( $dir ) ) { // make directory and its parents
 340                         $status->fatal( 'directorycreateerror', $params['dir'] );
 341                 } elseif ( !is_writable( $dir ) ) {
 342                         $status->fatal( 'directoryreadonlyerror', $params['dir'] );
 343                 } elseif ( !is_readable( $dir ) ) {
 344                         $status->fatal( 'directorynotreadableerror', $params['dir'] );
 345                 }
 346                 return $status;
 347         }
 348
 349         /**
 350          * @see FileBackend::doSecureInternal()
 351          */
 352         protected function doSecureInternal( $fullCont, $dirRel, array $params ) {
 353                 $status = Status::newGood();
 354                 list( $b, $shortCont, $r ) = FileBackend::splitStoragePath( $params['dir'] );
 355                 $contRoot = $this->containerFSRoot( $shortCont, $fullCont ); // must be valid
 356                 $dir = ( $dirRel != '' ) ? "{$contRoot}/{$dirRel}" : $contRoot;
 357                 // Seed new directories with a blank index.html, to prevent crawling...
 358                 if ( !empty( $params['noListing'] ) && !file_exists( "{$dir}/index.html" ) ) {
 359                         wfSuppressWarnings();
 360                         $ok = file_put_contents( "{$dir}/index.html", '' );
 361                         wfRestoreWarnings();
 362                         if ( !$ok ) {
 363                                 $status->fatal( 'backend-fail-create', $params['dir'] . '/index.html' );
 364                                 return $status;
 365                         }
 366                 }
 367                 // Add a .htaccess file to the root of the container...
 368                 if ( !empty( $params['noAccess'] ) ) {
 369                         if ( !file_exists( "{$contRoot}/.htaccess" ) ) {
 370                                 wfSuppressWarnings();
 371                                 $ok = file_put_contents( "{$contRoot}/.htaccess", "Deny from all\n" );
 372                                 wfRestoreWarnings();
 373                                 if ( !$ok ) {
 374                                         $storeDir = "mwstore://{$this->name}/{$shortCont}";
 375                                         $status->fatal( 'backend-fail-create', "{$storeDir}/.htaccess" );
 376                                         return $status;
 377                                 }
 378                         }
 379                 }
 380                 return $status;
 381         }
 382
 383         /**
 384          * @see FileBackend::doCleanInternal()
 385          */
 386         protected function doCleanInternal( $fullCont, $dirRel, array $params ) {
 387                 $status = Status::newGood();
 388                 list( $b, $shortCont, $r ) = FileBackend::splitStoragePath( $params['dir'] );
 389                 $contRoot = $this->containerFSRoot( $shortCont, $fullCont ); // must be valid
 390                 $dir = ( $dirRel != '' ) ? "{$contRoot}/{$dirRel}" : $contRoot;
 391                 wfSuppressWarnings();
 392                 if ( is_dir( $dir ) ) {
 393                         rmdir( $dir ); // remove directory if empty
 394                 }
 395                 wfRestoreWarnings();
 396                 return $status;
 397         }
 398
 399         /**
 400          * @see FileBackend::doFileExists()
 401          */
 402         protected function doGetFileStat( array $params ) {
 403                 $source = $this->resolveToFSPath( $params['src'] );
 404                 if ( $source === null ) {
 405                         return false; // invalid storage path
 406                 }
 407
 408                 $this->trapWarnings();
 409                 $stat = is_file( $source ) ? stat( $source ) : false; // regular files only
 410                 $hadError = $this->untrapWarnings();
 411
 412                 if ( $stat ) {
 413                         return array(
 414                                 'mtime' => wfTimestamp( TS_MW, $stat['mtime'] ),
 415                                 'size'  => $stat['size']
 416                         );
 417                 } elseif ( !$hadError ) {
 418                         return false; // file does not exist
 419                 } else {
 420                         return null; // failure
 421                 }
 422         }
 423
 424         /**
 425          * @see FileBackend::doClearCache()
 426          */
 427         protected function doClearCache( array $paths = null ) {
 428                 clearstatcache(); // clear the PHP file stat cache
 429         }
 430
 431         /**
 432          * @see FileBackend::getFileListInternal()
 433          */
 434         public function getFileListInternal( $fullCont, $dirRel, array $params ) {
 435                 list( $b, $shortCont, $r ) = FileBackend::splitStoragePath( $params['dir'] );
 436                 $contRoot = $this->containerFSRoot( $shortCont, $fullCont ); // must be valid
 437                 $dir = ( $dirRel != '' ) ? "{$contRoot}/{$dirRel}" : $contRoot;
 438                 wfSuppressWarnings();
 439                 $exists = is_dir( $dir );
 440                 wfRestoreWarnings();
 441                 if ( !$exists ) {
 442                         return array(); // nothing under this dir
 443                 }
 444                 wfSuppressWarnings();
 445                 $readable = is_readable( $dir );
 446                 wfRestoreWarnings();
 447                 if ( !$readable ) {
 448                         return null; // bad permissions?
 449                 }
 450                 return new FSFileBackendFileList( $dir );
 451         }
 452
 453         /**
 454          * @see FileBackend::getLocalReference()
 455          */
 456         public function getLocalReference( array $params ) {
 457                 $source = $this->resolveToFSPath( $params['src'] );
 458                 if ( $source === null ) {
 459                         return null;
 460                 }
 461                 return new FSFile( $source );
 462         }
 463
 464         /**
 465          * @see FileBackend::getLocalCopy()
 466          */
 467         public function getLocalCopy( array $params ) {
 468                 $source = $this->resolveToFSPath( $params['src'] );
 469                 if ( $source === null ) {
 470                         return null;
 471                 }
 472
 473                 // Create a new temporary file with the same extension...
 474                 $ext = FileBackend::extensionFromPath( $params['src'] );
 475                 $tmpFile = TempFSFile::factory( wfBaseName( $source ) . '_', $ext );
 476                 if ( !$tmpFile ) {
 477                         return null;
 478                 }
 479                 $tmpPath = $tmpFile->getPath();
 480
 481                 // Copy the source file over the temp file
 482                 wfSuppressWarnings();
 483                 $ok = copy( $source, $tmpPath );
 484                 wfRestoreWarnings();
 485                 if ( !$ok ) {
 486                         return null;
 487                 }
 488
 489                 $this->chmod( $tmpPath );
 490
 491                 return $tmpFile;
 492         }
 493
 494         /**
 495          * Chmod a file, suppressing the warnings
 496          *
 497          * @param $path string Absolute file system path
 498          * @return bool Success
 499          */
 500         protected function chmod( $path ) {
 501                 wfSuppressWarnings();
 502                 $ok = chmod( $path, $this->fileMode );
 503                 wfRestoreWarnings();
 504
 505                 return $ok;
 506         }
 507
 508         /**
 509          * Suppress E_WARNING errors and track whether any happen
 510          *
 511          * @return void
 512          */
 513         protected function trapWarnings() {
 514                 $this->hadWarningErrors[] = false; // push to stack
 515                 set_error_handler( array( $this, 'handleWarning' ), E_WARNING );
 516         }
 517
 518         /**
 519          * Unsuppress E_WARNING errors and return true if any happened
 520          *
 521          * @return bool
 522          */
 523         protected function untrapWarnings() {
 524                 restore_error_handler(); // restore previous handler
 525                 return array_pop( $this->hadWarningErrors ); // pop from stack
 526         }
 527
 528         private function handleWarning() {
 529                 $this->hadWarningErrors[count( $this->hadWarningErrors ) - 1] = true;
 530                 return true; // suppress from PHP handler
 531         }
 532 }
 533
 534 /**
 535  * Wrapper around RecursiveDirectoryIterator that catches
 536  * exception or does any custom behavoir that we may want.
 537  * Do not use this class from places outside FSFileBackend.
 538  *
 539  * @ingroup FileBackend
 540  */
 541 class FSFileBackendFileList implements Iterator {
 542         /** @var RecursiveIteratorIterator */
 543         protected $iter;
 544         protected $suffixStart; // integer
 545         protected $pos = 0; // integer
 546
 547         /**
 548          * @param $dir string file system directory
 549          */
 550         public function __construct( $dir ) {
 551                 $dir = realpath( $dir ); // normalize
 552                 $this->suffixStart = strlen( $dir ) + 1; // size of "path/to/dir/"
 553                 try {
 554                         # Get an iterator that will return leaf nodes (non-directories)
 555                         if ( MWInit::classExists( 'FilesystemIterator' ) ) { // PHP >= 5.3
 556                                 # RecursiveDirectoryIterator extends FilesystemIterator.
 557                                 # FilesystemIterator::SKIP_DOTS default is inconsistent in PHP 5.3.x.
 558                                 $flags = FilesystemIterator::CURRENT_AS_FILEINFO | FilesystemIterator::SKIP_DOTS;
 559                                 $this->iter = new RecursiveIteratorIterator(
 560                                         new RecursiveDirectoryIterator( $dir, $flags ) );
 561                         } else { // PHP < 5.3
 562                                 # RecursiveDirectoryIterator extends DirectoryIterator
 563                                 $this->iter = new RecursiveIteratorIterator(
 564                                         new RecursiveDirectoryIterator( $dir ) );
 565                         }
 566                 } catch ( UnexpectedValueException $e ) {
 567                         $this->iter = null; // bad permissions? deleted?
 568                 }
 569         }
 570
 571         public function current() {
 572                 // Return only the relative path and normalize slashes to FileBackend-style
 573                 // Make sure to use the realpath since the suffix is based upon that
 574                 return str_replace( '\\', '/',
 575                         substr( realpath( $this->iter->current() ), $this->suffixStart ) );
 576         }
 577
 578         public function key() {
 579                 return $this->pos;
 580         }
 581
 582         public function next() {
 583                 try {
 584                         $this->iter->next();
 585                 } catch ( UnexpectedValueException $e ) {
 586                         $this->iter = null;
 587                 }
 588                 ++$this->pos;
 589         }
 590
 591         public function rewind() {
 592                 $this->pos = 0;
 593                 try {
 594                         $this->iter->rewind();
 595                 } catch ( UnexpectedValueException $e ) {
 596                         $this->iter = null;
 597                 }
 598         }
 599
 600         public function valid() {
 601                 return $this->iter && $this->iter->valid();
 602         }
 603 }