includes/filebackend/FSFileBackend.php

   1 <?php
   2 /**
   3  * File system based backend.
   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  * @ingroup FileBackend
  22  * @author Aaron Schulz
  23  */
  24
  25 /**
  26  * @brief Class for a file system (FS) based file backend.
  27  *
  28  * All "containers" each map to a directory under the backend's base directory.
  29  * For backwards-compatibility, some container paths can be set to custom paths.
  30  * The wiki ID will not be used in any custom paths, so this should be avoided.
  31  *
  32  * Having directories with thousands of files will diminish performance.
  33  * Sharding can be accomplished by using FileRepo-style hash paths.
  34  *
  35  * Status messages should avoid mentioning the internal FS paths.
  36  * PHP warnings are assumed to be logged rather than output.
  37  *
  38  * @ingroup FileBackend
  39  * @since 1.19
  40  */
  41 class FSFileBackend extends FileBackendStore {
  42         protected $basePath; // string; directory holding the container directories
  43         /** @var Array Map of container names to root paths */
  44         protected $containerPaths = array(); // for custom container paths
  45         protected $fileMode; // integer; file permission mode
  46
  47         protected $hadWarningErrors = array();
  48
  49         /**
  50          * @see FileBackendStore::__construct()
  51          * Additional $config params include:
  52          *   - basePath       : File system directory that holds containers.
  53          *   - containerPaths : Map of container names to custom file system directories.
  54          *                      This should only be used for backwards-compatibility.
  55          *   - fileMode       : Octal UNIX file permissions to use on files stored.
  56          */
  57         public function __construct( array $config ) {
  58                 parent::__construct( $config );
  59
  60                 // Remove any possible trailing slash from directories
  61                 if ( isset( $config['basePath'] ) ) {
  62                         $this->basePath = rtrim( $config['basePath'], '/' ); // remove trailing slash
  63                 } else {
  64                         $this->basePath = null; // none; containers must have explicit paths
  65                 }
  66
  67                 if ( isset( $config['containerPaths'] ) ) {
  68                         $this->containerPaths = (array)$config['containerPaths'];
  69                         foreach ( $this->containerPaths as &$path ) {
  70                                 $path = rtrim( $path, '/' );  // remove trailing slash
  71                         }
  72                 }
  73
  74                 $this->fileMode = isset( $config['fileMode'] )
  75                         ? $config['fileMode']
  76                         : 0644;
  77         }
  78
  79         /**
  80          * @see FileBackendStore::resolveContainerPath()
  81          * @param $container string
  82          * @param $relStoragePath string
  83          * @return null|string
  84          */
  85         protected function resolveContainerPath( $container, $relStoragePath ) {
  86                 // Check that container has a root directory
  87                 if ( isset( $this->containerPaths[$container] ) || isset( $this->basePath ) ) {
  88                         // Check for sane relative paths (assume the base paths are OK)
  89                         if ( $this->isLegalRelPath( $relStoragePath ) ) {
  90                                 return $relStoragePath;
  91                         }
  92                 }
  93                 return null;
  94         }
  95
  96         /**
  97          * Sanity check a relative file system path for validity
  98          *
  99          * @param $path string Normalized relative path
 100          * @return bool
 101          */
 102         protected function isLegalRelPath( $path ) {
 103                 // Check for file names longer than 255 chars
 104                 if ( preg_match( '![^/]{256}!', $path ) ) { // ext3/NTFS
 105                         return false;
 106                 }
 107                 if ( wfIsWindows() ) { // NTFS
 108                         return !preg_match( '![:*?"<>|]!', $path );
 109                 } else {
 110                         return true;
 111                 }
 112         }
 113
 114         /**
 115          * Given the short (unresolved) and full (resolved) name of
 116          * a container, return the file system path of the container.
 117          *
 118          * @param $shortCont string
 119          * @param $fullCont string
 120          * @return string|null
 121          */
 122         protected function containerFSRoot( $shortCont, $fullCont ) {
 123                 if ( isset( $this->containerPaths[$shortCont] ) ) {
 124                         return $this->containerPaths[$shortCont];
 125                 } elseif ( isset( $this->basePath ) ) {
 126                         return "{$this->basePath}/{$fullCont}";
 127                 }
 128                 return null; // no container base path defined
 129         }
 130
 131         /**
 132          * Get the absolute file system path for a storage path
 133          *
 134          * @param $storagePath string Storage path
 135          * @return string|null
 136          */
 137         protected function resolveToFSPath( $storagePath ) {
 138                 list( $fullCont, $relPath ) = $this->resolveStoragePathReal( $storagePath );
 139                 if ( $relPath === null ) {
 140                         return null; // invalid
 141                 }
 142                 list( $b, $shortCont, $r ) = FileBackend::splitStoragePath( $storagePath );
 143                 $fsPath = $this->containerFSRoot( $shortCont, $fullCont ); // must be valid
 144                 if ( $relPath != '' ) {
 145                         $fsPath .= "/{$relPath}";
 146                 }
 147                 return $fsPath;
 148         }
 149
 150         /**
 151          * @see FileBackendStore::isPathUsableInternal()
 152          * @return bool
 153          */
 154         public function isPathUsableInternal( $storagePath ) {
 155                 $fsPath = $this->resolveToFSPath( $storagePath );
 156                 if ( $fsPath === null ) {
 157                         return false; // invalid
 158                 }
 159                 $parentDir = dirname( $fsPath );
 160
 161                 if ( file_exists( $fsPath ) ) {
 162                         $ok = is_file( $fsPath ) && is_writable( $fsPath );
 163                 } else {
 164                         $ok = is_dir( $parentDir ) && is_writable( $parentDir );
 165                 }
 166
 167                 return $ok;
 168         }
 169
 170         /**
 171          * @see FileBackendStore::doStoreInternal()
 172          * @return Status
 173          */
 174         protected function doStoreInternal( array $params ) {
 175                 $status = Status::newGood();
 176
 177                 $dest = $this->resolveToFSPath( $params['dst'] );
 178                 if ( $dest === null ) {
 179                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 180                         return $status;
 181                 }
 182
 183                 if ( file_exists( $dest ) ) {
 184                         if ( !empty( $params['overwrite'] ) ) {
 185                                 $ok = unlink( $dest );
 186                                 if ( !$ok ) {
 187                                         $status->fatal( 'backend-fail-delete', $params['dst'] );
 188                                         return $status;
 189                                 }
 190                         } else {
 191                                 $status->fatal( 'backend-fail-alreadyexists', $params['dst'] );
 192                                 return $status;
 193                         }
 194                 }
 195
 196                 if ( !empty( $params['async'] ) ) { // deferred
 197                         $cmd = implode( ' ', array( wfIsWindows() ? 'COPY' : 'cp',
 198                                 wfEscapeShellArg( $this->cleanPathSlashes( $params['src'] ) ),
 199                                 wfEscapeShellArg( $this->cleanPathSlashes( $dest ) )
 200                         ) );
 201                         $status->value = new FSFileOpHandle( $this, $params, 'Store', $cmd, $dest );
 202                 } else { // immediate write
 203                         $ok = copy( $params['src'], $dest );
 204                         // In some cases (at least over NFS), copy() returns true when it fails
 205                         if ( !$ok || ( filesize( $params['src'] ) !== filesize( $dest ) ) ) {
 206                                 if ( $ok ) { // PHP bug
 207                                         unlink( $dest ); // remove broken file
 208                                         trigger_error( __METHOD__ . ": copy() failed but returned true." );
 209                                 }
 210                                 $status->fatal( 'backend-fail-store', $params['src'], $params['dst'] );
 211                                 return $status;
 212                         }
 213                         $this->chmod( $dest );
 214                 }
 215
 216                 return $status;
 217         }
 218
 219         /**
 220          * @see FSFileBackend::doExecuteOpHandlesInternal()
 221          */
 222         protected function _getResponseStore( $errors, Status $status, array $params, $cmd ) {
 223                 if ( $errors !== '' && !( wfIsWindows() && $errors[0] === " " ) ) {
 224                         $status->fatal( 'backend-fail-store', $params['src'], $params['dst'] );
 225                         trigger_error( "$cmd\n$errors", E_USER_WARNING ); // command output
 226                 }
 227         }
 228
 229         /**
 230          * @see FileBackendStore::doCopyInternal()
 231          * @return Status
 232          */
 233         protected function doCopyInternal( array $params ) {
 234                 $status = Status::newGood();
 235
 236                 $source = $this->resolveToFSPath( $params['src'] );
 237                 if ( $source === null ) {
 238                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 239                         return $status;
 240                 }
 241
 242                 $dest = $this->resolveToFSPath( $params['dst'] );
 243                 if ( $dest === null ) {
 244                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 245                         return $status;
 246                 }
 247
 248                 if ( file_exists( $dest ) ) {
 249                         if ( !empty( $params['overwrite'] ) ) {
 250                                 $ok = unlink( $dest );
 251                                 if ( !$ok ) {
 252                                         $status->fatal( 'backend-fail-delete', $params['dst'] );
 253                                         return $status;
 254                                 }
 255                         } else {
 256                                 $status->fatal( 'backend-fail-alreadyexists', $params['dst'] );
 257                                 return $status;
 258                         }
 259                 }
 260
 261                 if ( !empty( $params['async'] ) ) { // deferred
 262                         $cmd = implode( ' ', array( wfIsWindows() ? 'COPY' : 'cp',
 263                                 wfEscapeShellArg( $this->cleanPathSlashes( $source ) ),
 264                                 wfEscapeShellArg( $this->cleanPathSlashes( $dest ) )
 265                         ) );
 266                         $status->value = new FSFileOpHandle( $this, $params, 'Copy', $cmd, $dest );
 267                 } else { // immediate write
 268                         $ok = copy( $source, $dest );
 269                         // In some cases (at least over NFS), copy() returns true when it fails
 270                         if ( !$ok || ( filesize( $source ) !== filesize( $dest ) ) ) {
 271                                 if ( $ok ) { // PHP bug
 272                                         unlink( $dest ); // remove broken file
 273                                         trigger_error( __METHOD__ . ": copy() failed but returned true." );
 274                                 }
 275                                 $status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
 276                                 return $status;
 277                         }
 278                         $this->chmod( $dest );
 279                 }
 280
 281                 return $status;
 282         }
 283
 284         /**
 285          * @see FSFileBackend::doExecuteOpHandlesInternal()
 286          */
 287         protected function _getResponseCopy( $errors, Status $status, array $params, $cmd ) {
 288                 if ( $errors !== '' && !( wfIsWindows() && $errors[0] === " " ) ) {
 289                         $status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
 290                         trigger_error( "$cmd\n$errors", E_USER_WARNING ); // command output
 291                 }
 292         }
 293
 294         /**
 295          * @see FileBackendStore::doMoveInternal()
 296          * @return Status
 297          */
 298         protected function doMoveInternal( array $params ) {
 299                 $status = Status::newGood();
 300
 301                 $source = $this->resolveToFSPath( $params['src'] );
 302                 if ( $source === null ) {
 303                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 304                         return $status;
 305                 }
 306
 307                 $dest = $this->resolveToFSPath( $params['dst'] );
 308                 if ( $dest === null ) {
 309                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 310                         return $status;
 311                 }
 312
 313                 if ( file_exists( $dest ) ) {
 314                         if ( !empty( $params['overwrite'] ) ) {
 315                                 // Windows does not support moving over existing files
 316                                 if ( wfIsWindows() ) {
 317                                         $ok = unlink( $dest );
 318                                         if ( !$ok ) {
 319                                                 $status->fatal( 'backend-fail-delete', $params['dst'] );
 320                                                 return $status;
 321                                         }
 322                                 }
 323                         } else {
 324                                 $status->fatal( 'backend-fail-alreadyexists', $params['dst'] );
 325                                 return $status;
 326                         }
 327                 }
 328
 329                 if ( !empty( $params['async'] ) ) { // deferred
 330                         $cmd = implode( ' ', array( wfIsWindows() ? 'MOVE' : 'mv',
 331                                 wfEscapeShellArg( $this->cleanPathSlashes( $source ) ),
 332                                 wfEscapeShellArg( $this->cleanPathSlashes( $dest ) )
 333                         ) );
 334                         $status->value = new FSFileOpHandle( $this, $params, 'Move', $cmd );
 335                 } else { // immediate write
 336                         $ok = rename( $source, $dest );
 337                         clearstatcache(); // file no longer at source
 338                         if ( !$ok ) {
 339                                 $status->fatal( 'backend-fail-move', $params['src'], $params['dst'] );
 340                                 return $status;
 341                         }
 342                 }
 343
 344                 return $status;
 345         }
 346
 347         /**
 348          * @see FSFileBackend::doExecuteOpHandlesInternal()
 349          */
 350         protected function _getResponseMove( $errors, Status $status, array $params, $cmd ) {
 351                 if ( $errors !== '' && !( wfIsWindows() && $errors[0] === " " ) ) {
 352                         $status->fatal( 'backend-fail-move', $params['src'], $params['dst'] );
 353                         trigger_error( "$cmd\n$errors", E_USER_WARNING ); // command output
 354                 }
 355         }
 356
 357         /**
 358          * @see FileBackendStore::doDeleteInternal()
 359          * @return Status
 360          */
 361         protected function doDeleteInternal( array $params ) {
 362                 $status = Status::newGood();
 363
 364                 $source = $this->resolveToFSPath( $params['src'] );
 365                 if ( $source === null ) {
 366                         $status->fatal( 'backend-fail-invalidpath', $params['src'] );
 367                         return $status;
 368                 }
 369
 370                 if ( !is_file( $source ) ) {
 371                         if ( empty( $params['ignoreMissingSource'] ) ) {
 372                                 $status->fatal( 'backend-fail-delete', $params['src'] );
 373                         }
 374                         return $status; // do nothing; either OK or bad status
 375                 }
 376
 377                 if ( !empty( $params['async'] ) ) { // deferred
 378                         $cmd = implode( ' ', array( wfIsWindows() ? 'DEL' : 'unlink',
 379                                 wfEscapeShellArg( $this->cleanPathSlashes( $source ) )
 380                         ) );
 381                         $status->value = new FSFileOpHandle( $this, $params, 'Copy', $cmd );
 382                 } else { // immediate write
 383                         $ok = unlink( $source );
 384                         if ( !$ok ) {
 385                                 $status->fatal( 'backend-fail-delete', $params['src'] );
 386                                 return $status;
 387                         }
 388                 }
 389
 390                 return $status;
 391         }
 392
 393         /**
 394          * @see FSFileBackend::doExecuteOpHandlesInternal()
 395          */
 396         protected function _getResponseDelete( $errors, Status $status, array $params, $cmd ) {
 397                 if ( $errors !== '' && !( wfIsWindows() && $errors[0] === " " ) ) {
 398                         $status->fatal( 'backend-fail-delete', $params['src'] );
 399                         trigger_error( "$cmd\n$errors", E_USER_WARNING ); // command output
 400                 }
 401         }
 402
 403         /**
 404          * @see FileBackendStore::doCreateInternal()
 405          * @return Status
 406          */
 407         protected function doCreateInternal( array $params ) {
 408                 $status = Status::newGood();
 409
 410                 $dest = $this->resolveToFSPath( $params['dst'] );
 411                 if ( $dest === null ) {
 412                         $status->fatal( 'backend-fail-invalidpath', $params['dst'] );
 413                         return $status;
 414                 }
 415
 416                 if ( file_exists( $dest ) ) {
 417                         if ( !empty( $params['overwrite'] ) ) {
 418                                 $ok = unlink( $dest );
 419                                 if ( !$ok ) {
 420                                         $status->fatal( 'backend-fail-delete', $params['dst'] );
 421                                         return $status;
 422                                 }
 423                         } else {
 424                                 $status->fatal( 'backend-fail-alreadyexists', $params['dst'] );
 425                                 return $status;
 426                         }
 427                 }
 428
 429                 if ( !empty( $params['async'] ) ) { // deferred
 430                         $tempFile = TempFSFile::factory( 'create_', 'tmp' );
 431                         if ( !$tempFile ) {
 432                                 $status->fatal( 'backend-fail-create', $params['dst'] );
 433                                 return $status;
 434                         }
 435                         $bytes = file_put_contents( $tempFile->getPath(), $params['content'] );
 436                         if ( $bytes === false ) {
 437                                 $status->fatal( 'backend-fail-create', $params['dst'] );
 438                                 return $status;
 439                         }
 440                         $cmd = implode( ' ', array( wfIsWindows() ? 'COPY' : 'cp',
 441                                 wfEscapeShellArg( $this->cleanPathSlashes( $tempFile->getPath() ) ),
 442                                 wfEscapeShellArg( $this->cleanPathSlashes( $dest ) )
 443                         ) );
 444                         $status->value = new FSFileOpHandle( $this, $params, 'Create', $cmd, $dest );
 445                         $tempFile->bind( $status->value );
 446                 } else { // immediate write
 447                         $bytes = file_put_contents( $dest, $params['content'] );
 448                         if ( $bytes === false ) {
 449                                 $status->fatal( 'backend-fail-create', $params['dst'] );
 450                                 return $status;
 451                         }
 452                         $this->chmod( $dest );
 453                 }
 454
 455                 return $status;
 456         }
 457
 458         /**
 459          * @see FSFileBackend::doExecuteOpHandlesInternal()
 460          */
 461         protected function _getResponseCreate( $errors, Status $status, array $params, $cmd ) {
 462                 if ( $errors !== '' && !( wfIsWindows() && $errors[0] === " " ) ) {
 463                         $status->fatal( 'backend-fail-create', $params['dst'] );
 464                         trigger_error( "$cmd\n$errors", E_USER_WARNING ); // command output
 465                 }
 466         }
 467
 468         /**
 469          * @see FileBackendStore::doPrepareInternal()
 470          * @return Status
 471          */
 472         protected function doPrepareInternal( $fullCont, $dirRel, array $params ) {
 473                 $status = Status::newGood();
 474                 list( $b, $shortCont, $r ) = FileBackend::splitStoragePath( $params['dir'] );
 475                 $contRoot = $this->containerFSRoot( $shortCont, $fullCont ); // must be valid
 476                 $dir = ( $dirRel != '' ) ? "{$contRoot}/{$dirRel}" : $contRoot;
 477                 $existed = is_dir( $dir ); // already there?
 478                 if ( !wfMkdirParents( $dir ) ) { // make directory and its parents
 479                         $status->fatal( 'directorycreateerror', $params['dir'] ); // fails on races
 480                 } elseif ( !is_writable( $dir ) ) {
 481                         $status->fatal( 'directoryreadonlyerror', $params['dir'] );
 482                 } elseif ( !is_readable( $dir ) ) {
 483                         $status->fatal( 'directorynotreadableerror', $params['dir'] );
 484                 }
 485                 if ( is_dir( $dir ) && !$existed ) {
 486                         // Respect any 'noAccess' or 'noListing' flags...
 487                         $status->merge( $this->doSecureInternal( $fullCont, $dirRel, $params ) );
 488                 }
 489                 return $status;
 490         }
 491
 492         /**
 493          * @see FileBackendStore::doSecureInternal()
 494          * @return Status
 495          */
 496         protected function doSecureInternal( $fullCont, $dirRel, array $params ) {
 497                 $status = Status::newGood();
 498                 list( $b, $shortCont, $r ) = FileBackend::splitStoragePath( $params['dir'] );
 499                 $contRoot = $this->containerFSRoot( $shortCont, $fullCont ); // must be valid
 500                 $dir = ( $dirRel != '' ) ? "{$contRoot}/{$dirRel}" : $contRoot;
 501                 // Seed new directories with a blank index.html, to prevent crawling...
 502                 if ( !empty( $params['noListing'] ) && !file_exists( "{$dir}/index.html" ) ) {
 503                         $bytes = file_put_contents( "{$dir}/index.html", $this->indexHtmlPrivate() );
 504                         if ( $bytes === false ) {
 505                                 $status->fatal( 'backend-fail-create', $params['dir'] . '/index.html' );
 506                                 return $status;
 507                         }
 508                 }
 509                 // Add a .htaccess file to the root of the container...
 510                 if ( !empty( $params['noAccess'] ) && !file_exists( "{$contRoot}/.htaccess" ) ) {
 511                         $bytes = file_put_contents( "{$contRoot}/.htaccess", $this->htaccessPrivate() );
 512                         if ( $bytes === false ) {
 513                                 $storeDir = "mwstore://{$this->name}/{$shortCont}";
 514                                 $status->fatal( 'backend-fail-create', "{$storeDir}/.htaccess" );
 515                                 return $status;
 516                         }
 517                 }
 518                 return $status;
 519         }
 520
 521         /**
 522          * @see FileBackendStore::doPublishInternal()
 523          * @return Status
 524          */
 525         protected function doPublishInternal( $fullCont, $dirRel, array $params ) {
 526                 $status = Status::newGood();
 527                 list( $b, $shortCont, $r ) = FileBackend::splitStoragePath( $params['dir'] );
 528                 $contRoot = $this->containerFSRoot( $shortCont, $fullCont ); // must be valid
 529                 $dir = ( $dirRel != '' ) ? "{$contRoot}/{$dirRel}" : $contRoot;
 530                 // Unseed new directories with a blank index.html, to allow crawling...
 531                 if ( !empty( $params['listing'] ) && is_file( "{$dir}/index.html" ) ) {
 532                         $exists = ( file_get_contents( "{$dir}/index.html" ) === $this->indexHtmlPrivate() );
 533                         if ( $exists && !unlink( "{$dir}/index.html" ) ) { // reverse secure()
 534                                 $status->fatal( 'backend-fail-delete', $params['dir'] . '/index.html' );
 535                                 return $status;
 536                         }
 537                 }
 538                 // Remove the .htaccess file from the root of the container...
 539                 if ( !empty( $params['access'] ) && is_file( "{$contRoot}/.htaccess" ) ) {
 540                         $exists = ( file_get_contents( "{$contRoot}/.htaccess" ) === $this->htaccessPrivate() );
 541                         if ( $exists && !unlink( "{$contRoot}/.htaccess" ) ) { // reverse secure()
 542                                 $storeDir = "mwstore://{$this->name}/{$shortCont}";
 543                                 $status->fatal( 'backend-fail-delete', "{$storeDir}/.htaccess" );
 544                                 return $status;
 545                         }
 546                 }
 547                 return $status;
 548         }
 549
 550         /**
 551          * @see FileBackendStore::doCleanInternal()
 552          * @return Status
 553          */
 554         protected function doCleanInternal( $fullCont, $dirRel, array $params ) {
 555                 $status = Status::newGood();
 556                 list( $b, $shortCont, $r ) = FileBackend::splitStoragePath( $params['dir'] );
 557                 $contRoot = $this->containerFSRoot( $shortCont, $fullCont ); // must be valid
 558                 $dir = ( $dirRel != '' ) ? "{$contRoot}/{$dirRel}" : $contRoot;
 559                 wfSuppressWarnings();
 560                 if ( is_dir( $dir ) ) {
 561                         rmdir( $dir ); // remove directory if empty
 562                 }
 563                 wfRestoreWarnings();
 564                 return $status;
 565         }
 566
 567         /**
 568          * @see FileBackendStore::doFileExists()
 569          * @return array|bool|null
 570          */
 571         protected function doGetFileStat( array $params ) {
 572                 $source = $this->resolveToFSPath( $params['src'] );
 573                 if ( $source === null ) {
 574                         return false; // invalid storage path
 575                 }
 576
 577                 $this->trapWarnings(); // don't trust 'false' if there were errors
 578                 $stat = is_file( $source ) ? stat( $source ) : false; // regular files only
 579                 $hadError = $this->untrapWarnings();
 580
 581                 if ( $stat ) {
 582                         return array(
 583                                 'mtime' => wfTimestamp( TS_MW, $stat['mtime'] ),
 584                                 'size'  => $stat['size']
 585                         );
 586                 } elseif ( !$hadError ) {
 587                         return false; // file does not exist
 588                 } else {
 589                         return null; // failure
 590                 }
 591         }
 592
 593         /**
 594          * @see FileBackendStore::doClearCache()
 595          */
 596         protected function doClearCache( array $paths = null ) {
 597                 clearstatcache(); // clear the PHP file stat cache
 598         }
 599
 600         /**
 601          * @see FileBackendStore::doDirectoryExists()
 602          * @return bool|null
 603          */
 604         protected function doDirectoryExists( $fullCont, $dirRel, array $params ) {
 605                 list( $b, $shortCont, $r ) = FileBackend::splitStoragePath( $params['dir'] );
 606                 $contRoot = $this->containerFSRoot( $shortCont, $fullCont ); // must be valid
 607                 $dir = ( $dirRel != '' ) ? "{$contRoot}/{$dirRel}" : $contRoot;
 608
 609                 $this->trapWarnings(); // don't trust 'false' if there were errors
 610                 $exists = is_dir( $dir );
 611                 $hadError = $this->untrapWarnings();
 612
 613                 return $hadError ? null : $exists;
 614         }
 615
 616         /**
 617          * @see FileBackendStore::getDirectoryListInternal()
 618          * @return Array|null
 619          */
 620         public function getDirectoryListInternal( $fullCont, $dirRel, array $params ) {
 621                 list( $b, $shortCont, $r ) = FileBackend::splitStoragePath( $params['dir'] );
 622                 $contRoot = $this->containerFSRoot( $shortCont, $fullCont ); // must be valid
 623                 $dir = ( $dirRel != '' ) ? "{$contRoot}/{$dirRel}" : $contRoot;
 624                 $exists = is_dir( $dir );
 625                 if ( !$exists ) {
 626                         wfDebug( __METHOD__ . "() given directory does not exist: '$dir'\n" );
 627                         return array(); // nothing under this dir
 628                 } elseif ( !is_readable( $dir ) ) {
 629                         wfDebug( __METHOD__ . "() given directory is unreadable: '$dir'\n" );
 630                         return null; // bad permissions?
 631                 }
 632                 return new FSFileBackendDirList( $dir, $params );
 633         }
 634
 635         /**
 636          * @see FileBackendStore::getFileListInternal()
 637          * @return array|FSFileBackendFileList|null
 638          */
 639         public function getFileListInternal( $fullCont, $dirRel, array $params ) {
 640                 list( $b, $shortCont, $r ) = FileBackend::splitStoragePath( $params['dir'] );
 641                 $contRoot = $this->containerFSRoot( $shortCont, $fullCont ); // must be valid
 642                 $dir = ( $dirRel != '' ) ? "{$contRoot}/{$dirRel}" : $contRoot;
 643                 $exists = is_dir( $dir );
 644                 if ( !$exists ) {
 645                         wfDebug( __METHOD__ . "() given directory does not exist: '$dir'\n" );
 646                         return array(); // nothing under this dir
 647                 } elseif ( !is_readable( $dir ) ) {
 648                         wfDebug( __METHOD__ . "() given directory is unreadable: '$dir'\n" );
 649                         return null; // bad permissions?
 650                 }
 651                 return new FSFileBackendFileList( $dir, $params );
 652         }
 653
 654         /**
 655          * @see FileBackendStore::getLocalReference()
 656          * @return FSFile|null
 657          */
 658         public function getLocalReference( array $params ) {
 659                 $source = $this->resolveToFSPath( $params['src'] );
 660                 if ( $source === null ) {
 661                         return null;
 662                 }
 663                 return new FSFile( $source );
 664         }
 665
 666         /**
 667          * @see FileBackendStore::getLocalCopy()
 668          * @return null|TempFSFile
 669          */
 670         public function getLocalCopy( array $params ) {
 671                 $source = $this->resolveToFSPath( $params['src'] );
 672                 if ( $source === null ) {
 673                         return null;
 674                 }
 675
 676                 // Create a new temporary file with the same extension...
 677                 $ext = FileBackend::extensionFromPath( $params['src'] );
 678                 $tmpFile = TempFSFile::factory( wfBaseName( $source ) . '_', $ext );
 679                 if ( !$tmpFile ) {
 680                         return null;
 681                 }
 682                 $tmpPath = $tmpFile->getPath();
 683
 684                 // Copy the source file over the temp file
 685                 $ok = copy( $source, $tmpPath );
 686                 if ( !$ok ) {
 687                         return null;
 688                 }
 689
 690                 $this->chmod( $tmpPath );
 691
 692                 return $tmpFile;
 693         }
 694
 695         /**
 696          * @see FileBackendStore::directoriesAreVirtual()
 697          * @return bool
 698          */
 699         protected function directoriesAreVirtual() {
 700                 return false;
 701         }
 702
 703         /**
 704          * @see FileBackendStore::doExecuteOpHandlesInternal()
 705          * @return Array List of corresponding Status objects
 706          */
 707         protected function doExecuteOpHandlesInternal( array $fileOpHandles ) {
 708                 $statuses = array();
 709
 710                 $pipes = array();
 711                 foreach ( $fileOpHandles as $index => $fileOpHandle ) {
 712                         $pipes[$index] = popen( "{$fileOpHandle->cmd} 2>&1", 'r' );
 713                 }
 714
 715                 $errs = array();
 716                 foreach ( $pipes as $index => $pipe ) {
 717                         // Result will be empty on success in *NIX. On Windows,
 718                         // it may be something like "        1 file(s) [copied|moved].".
 719                         $errs[$index] = stream_get_contents( $pipe );
 720                         fclose( $pipe );
 721                 }
 722
 723                 foreach ( $fileOpHandles as $index => $fileOpHandle ) {
 724                         $status = Status::newGood();
 725                         $function = '_getResponse' . $fileOpHandle->call;
 726                         $this->$function( $errs[$index], $status, $fileOpHandle->params, $fileOpHandle->cmd );
 727                         $statuses[$index] = $status;
 728                         if ( $status->isOK() && $fileOpHandle->chmodPath ) {
 729                                 $this->chmod( $fileOpHandle->chmodPath );
 730                         }
 731                 }
 732
 733                 clearstatcache(); // files changed
 734                 return $statuses;
 735         }
 736
 737         /**
 738          * Chmod a file, suppressing the warnings
 739          *
 740          * @param $path string Absolute file system path
 741          * @return bool Success
 742          */
 743         protected function chmod( $path ) {
 744                 wfSuppressWarnings();
 745                 $ok = chmod( $path, $this->fileMode );
 746                 wfRestoreWarnings();
 747
 748                 return $ok;
 749         }
 750
 751         /**
 752          * Return the text of an index.html file to hide directory listings
 753          *
 754          * @return string
 755          */
 756         protected function indexHtmlPrivate() {
 757                 return '';
 758         }
 759
 760         /**
 761          * Return the text of a .htaccess file to make a directory private
 762          *
 763          * @return string
 764          */
 765         protected function htaccessPrivate() {
 766                 return "Deny from all\n";
 767         }
 768
 769         /**
 770          * Clean up directory separators for the given OS
 771          *
 772          * @param $path string FS path
 773          * @return string
 774          */
 775         protected function cleanPathSlashes( $path ) {
 776                 return wfIsWindows() ? strtr( $path, '/', '\\' ) : $path;
 777         }
 778
 779         /**
 780          * Listen for E_WARNING errors and track whether any happen
 781          *
 782          * @return bool
 783          */
 784         protected function trapWarnings() {
 785                 $this->hadWarningErrors[] = false; // push to stack
 786                 set_error_handler( array( $this, 'handleWarning' ), E_WARNING );
 787                 return false; // invoke normal PHP error handler
 788         }
 789
 790         /**
 791          * Stop listening for E_WARNING errors and return true if any happened
 792          *
 793          * @return bool
 794          */
 795         protected function untrapWarnings() {
 796                 restore_error_handler(); // restore previous handler
 797                 return array_pop( $this->hadWarningErrors ); // pop from stack
 798         }
 799
 800         /**
 801          * @return bool
 802          */
 803         private function handleWarning() {
 804                 $this->hadWarningErrors[count( $this->hadWarningErrors ) - 1] = true;
 805                 return true; // suppress from PHP handler
 806         }
 807 }
 808
 809 /**
 810  * @see FileBackendStoreOpHandle
 811  */
 812 class FSFileOpHandle extends FileBackendStoreOpHandle {
 813         public $cmd; // string; shell command
 814         public $chmodPath; // string; file to chmod
 815
 816         /**
 817          * @param $backend
 818          * @param $params array
 819          * @param $call
 820          * @param $cmd
 821          * @param $chmodPath null
 822          */
 823         public function __construct( $backend, array $params, $call, $cmd, $chmodPath = null ) {
 824                 $this->backend = $backend;
 825                 $this->params = $params;
 826                 $this->call = $call;
 827                 $this->cmd = $cmd;
 828                 $this->chmodPath = $chmodPath;
 829         }
 830 }
 831
 832 /**
 833  * Wrapper around RecursiveDirectoryIterator/DirectoryIterator that
 834  * catches exception or does any custom behavoir that we may want.
 835  * Do not use this class from places outside FSFileBackend.
 836  *
 837  * @ingroup FileBackend
 838  */
 839 abstract class FSFileBackendList implements Iterator {
 840         /** @var Iterator */
 841         protected $iter;
 842         protected $suffixStart; // integer
 843         protected $pos = 0; // integer
 844         /** @var Array */
 845         protected $params = array();
 846
 847         /**
 848          * @param $dir string file system directory
 849          * @param $params array
 850          */
 851         public function __construct( $dir, array $params ) {
 852                 $dir = realpath( $dir ); // normalize
 853                 $this->suffixStart = strlen( $dir ) + 1; // size of "path/to/dir/"
 854                 $this->params = $params;
 855
 856                 try {
 857                         $this->iter = $this->initIterator( $dir );
 858                 } catch ( UnexpectedValueException $e ) {
 859                         $this->iter = null; // bad permissions? deleted?
 860                 }
 861         }
 862
 863         /**
 864          * Return an appropriate iterator object to wrap
 865          *
 866          * @param $dir string file system directory
 867          * @return Iterator
 868          */
 869         protected function initIterator( $dir ) {
 870                 if ( !empty( $this->params['topOnly'] ) ) { // non-recursive
 871                         # Get an iterator that will get direct sub-nodes
 872                         return new DirectoryIterator( $dir );
 873                 } else { // recursive
 874                         # Get an iterator that will return leaf nodes (non-directories)
 875                         # RecursiveDirectoryIterator extends FilesystemIterator.
 876                         # FilesystemIterator::SKIP_DOTS default is inconsistent in PHP 5.3.x.
 877                         $flags = FilesystemIterator::CURRENT_AS_SELF | FilesystemIterator::SKIP_DOTS;
 878                         return new RecursiveIteratorIterator(
 879                                 new RecursiveDirectoryIterator( $dir, $flags ),
 880                                 RecursiveIteratorIterator::CHILD_FIRST // include dirs
 881                         );
 882                 }
 883         }
 884
 885         /**
 886          * @see Iterator::key()
 887          * @return integer
 888          */
 889         public function key() {
 890                 return $this->pos;
 891         }
 892
 893         /**
 894          * @see Iterator::current()
 895          * @return string|bool String or false
 896          */
 897         public function current() {
 898                 return $this->getRelPath( $this->iter->current()->getPathname() );
 899         }
 900
 901         /**
 902          * @see Iterator::next()
 903          * @return void
 904          */
 905         public function next() {
 906                 try {
 907                         $this->iter->next();
 908                         $this->filterViaNext();
 909                 } catch ( UnexpectedValueException $e ) {
 910                         $this->iter = null;
 911                 }
 912                 ++$this->pos;
 913         }
 914
 915         /**
 916          * @see Iterator::rewind()
 917          * @return void
 918          */
 919         public function rewind() {
 920                 $this->pos = 0;
 921                 try {
 922                         $this->iter->rewind();
 923                         $this->filterViaNext();
 924                 } catch ( UnexpectedValueException $e ) {
 925                         $this->iter = null;
 926                 }
 927         }
 928
 929         /**
 930          * @see Iterator::valid()
 931          * @return bool
 932          */
 933         public function valid() {
 934                 return $this->iter && $this->iter->valid();
 935         }
 936
 937         /**
 938          * Filter out items by advancing to the next ones
 939          */
 940         protected function filterViaNext() {}
 941
 942         /**
 943          * Return only the relative path and normalize slashes to FileBackend-style.
 944          * Uses the "real path" since the suffix is based upon that.
 945          *
 946          * @param $path string
 947          * @return string
 948          */
 949         protected function getRelPath( $path ) {
 950                 return strtr( substr( realpath( $path ), $this->suffixStart ), '\\', '/' );
 951         }
 952 }
 953
 954 class FSFileBackendDirList extends FSFileBackendList {
 955         protected function filterViaNext() {
 956                 while ( $this->iter->valid() ) {
 957                         if ( $this->iter->current()->isDot() || !$this->iter->current()->isDir() ) {
 958                                 $this->iter->next(); // skip non-directories and dot files
 959                         } else {
 960                                 break;
 961                         }
 962                 }
 963         }
 964 }
 965
 966 class FSFileBackendFileList extends FSFileBackendList {
 967         protected function filterViaNext() {
 968                 while ( $this->iter->valid() ) {
 969                         if ( !$this->iter->current()->isFile() ) {
 970                                 $this->iter->next(); // skip non-files and dot files
 971                         } else {
 972                                 break;
 973                         }
 974                 }
 975         }
 976 }