includes/libs/filebackend/FSFileBackend.php
<?php
/**
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
* http://www.gnu.org/copyleft/gpl.html
*
* @file
* @ingroup FileBackend
*/
/**
* File system based backend.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
* http://www.gnu.org/copyleft/gpl.html
*
* @file
* @ingroup FileBackend
*/
use Shellbox\Shellbox;
use Wikimedia\AtEase\AtEase;
use Wikimedia\Timestamp\ConvertibleTimestamp;
/**
* @brief Class for a file system (FS) based file backend.
*
* All "containers" each map to a directory under the backend's base directory.
* For backwards-compatibility, some container paths can be set to custom paths.
* The domain ID will not be used in any custom paths, so this should be avoided.
*
* Having directories with thousands of files will diminish performance.
* Sharding can be accomplished by using FileRepo-style hash paths.
*
* StatusValue messages should avoid mentioning the internal FS paths.
* PHP warnings are assumed to be logged rather than output.
*
* @ingroup FileBackend
* @since 1.19
*/
class FSFileBackend extends FileBackendStore {
/** @var MapCacheLRU Cache for known prepared/usable directories */
protected $usableDirCache;
/** @var string|null Directory holding the container directories */
protected $basePath;
/** @var array<string,string> Map of container names to root paths for custom container paths */
protected $containerPaths;
/** @var int Directory permission mode */
protected $dirMode;
/** @var int File permission mode */
protected $fileMode;
/** @var string Required OS username to own files */
protected $fileOwner;
/** @var string Simpler version of PHP_OS_FAMILY */
protected $os;
/** @var string OS username running this script */
protected $currentUser;
/** @var bool[] Map of (stack index => whether a warning happened) */
private $warningTrapStack = [];
/**
* @see FileBackendStore::__construct()
* Additional $config params include:
* - basePath : File system directory that holds containers.
* - containerPaths : Map of container names to custom file system directories.
* This should only be used for backwards-compatibility.
* - fileMode : Octal UNIX file permissions to use on files stored.
* - directoryMode : Octal UNIX file permissions to use on directories created.
* @param array $config
*/
public function __construct( array $config ) {
parent::__construct( $config );
if ( PHP_OS_FAMILY === 'Windows' ) {
$this->os = 'Windows';
} elseif ( PHP_OS_FAMILY === 'BSD' || PHP_OS_FAMILY === 'Darwin' ) {
$this->os = 'BSD';
} else {
$this->os = 'Linux';
}
// Remove any possible trailing slash from directories
if ( isset( $config['basePath'] ) ) {
$this->basePath = rtrim( $config['basePath'], '/' ); // remove trailing slash
} else {
$this->basePath = null; // none; containers must have explicit paths
}
$this->containerPaths = [];
foreach ( ( $config['containerPaths'] ?? [] ) as $container => $fsPath ) {
$this->containerPaths[$container] = rtrim( $fsPath, '/' ); // remove trailing slash
}
$this->fileMode = $config['fileMode'] ?? 0644;
$this->dirMode = $config['directoryMode'] ?? 0777;
if ( isset( $config['fileOwner'] ) && function_exists( 'posix_getuid' ) ) {
$this->fileOwner = $config['fileOwner'];
// Cache this, assuming it doesn't change
$this->currentUser = posix_getpwuid( posix_getuid() )['name'];
}
$this->usableDirCache = new MapCacheLRU( self::CACHE_CHEAP_SIZE );
}
public function getFeatures() {
return self::ATTR_UNICODE_PATHS;
}
protected function resolveContainerPath( $container, $relStoragePath ) {
// Check that container has a root directory
if ( isset( $this->containerPaths[$container] ) || isset( $this->basePath ) ) {
// Check for sensible relative paths (assume the base paths are OK)
if ( $this->isLegalRelPath( $relStoragePath ) ) {
return $relStoragePath;
}
}
return null; // invalid
}
/**
* Check a relative file system path for validity
*
* @param string $fsPath Normalized relative path
* @return bool
*/
protected function isLegalRelPath( $fsPath ) {
// Check for file names longer than 255 chars
if ( preg_match( '![^/]{256}!', $fsPath ) ) { // ext3/NTFS
return false;
}
if ( $this->os === 'Windows' ) { // NTFS
return !preg_match( '![:*?"<>|]!', $fsPath );
} else {
return true;
}
}
/**
* Given the short (unresolved) and full (resolved) name of
* a container, return the file system path of the container.
*
* @param string $shortCont
* @param string $fullCont
* @return string|null
*/
protected function containerFSRoot( $shortCont, $fullCont ) {
if ( isset( $this->containerPaths[$shortCont] ) ) {
return $this->containerPaths[$shortCont];
} elseif ( isset( $this->basePath ) ) {
return "{$this->basePath}/{$fullCont}";
}
return null; // no container base path defined
}
/**
* Get the absolute file system path for a storage path
*
* @param string $storagePath
* @return string|null
*/
protected function resolveToFSPath( $storagePath ) {
[ $fullCont, $relPath ] = $this->resolveStoragePathReal( $storagePath );
if ( $relPath === null ) {
return null; // invalid
}
[ , $shortCont, ] = FileBackend::splitStoragePath( $storagePath );
$fsPath = $this->containerFSRoot( $shortCont, $fullCont ); // must be valid
if ( $relPath != '' ) {
$fsPath .= "/{$relPath}";
}
return $fsPath;
}
public function isPathUsableInternal( $storagePath ) {
$fsPath = $this->resolveToFSPath( $storagePath );
if ( $fsPath === null ) {
return false; // invalid
}
if ( $this->fileOwner !== null && $this->currentUser !== $this->fileOwner ) {
trigger_error( __METHOD__ . ": PHP process owner is not '{$this->fileOwner}'." );
return false;
}
$fsDirectory = dirname( $fsPath );
$usable = $this->usableDirCache->get( $fsDirectory, MapCacheLRU::TTL_PROC_SHORT );
if ( $usable === null ) {
AtEase::suppressWarnings();
$usable = is_dir( $fsDirectory ) && is_writable( $fsDirectory );
AtEase::restoreWarnings();
$this->usableDirCache->set( $fsDirectory, $usable ? 1 : 0 );
}
return $usable;
}
protected function doCreateInternal( array $params ) {
$status = $this->newStatus();
$fsDstPath = $this->resolveToFSPath( $params['dst'] );
if ( $fsDstPath === null ) {
$status->fatal( 'backend-fail-invalidpath', $params['dst'] );
return $status;
}
if ( !empty( $params['async'] ) ) { // deferred
$tempFile = $this->newTempFileWithContent( $params );
if ( !$tempFile ) {
$status->fatal( 'backend-fail-create', $params['dst'] );
return $status;
}
$cmd = $this->makeCopyCommand( $tempFile->getPath(), $fsDstPath, false );
$handler = function ( $errors, StatusValue $status, array $params, $cmd ) {
if ( $errors !== '' && !( $this->os === 'Windows' && $errors[0] === " " ) ) {
$status->fatal( 'backend-fail-create', $params['dst'] );
trigger_error( "$cmd\n$errors", E_USER_WARNING ); // command output
}
};
$status->value = new FSFileOpHandle( $this, $params, $handler, $cmd );
$tempFile->bind( $status->value );
} else { // immediate write
$created = false;
// Use fwrite+rename since (a) this clears xattrs, (b) threads still reading the old
// inode are unaffected since it writes to a new inode, and (c) new threads reading
// the file will either totally see the old version or totally see the new version
$fsStagePath = $this->makeStagingPath( $fsDstPath );
$this->trapWarningsIgnoringNotFound();
$stageHandle = fopen( $fsStagePath, 'xb' );
if ( $stageHandle ) {
$bytes = fwrite( $stageHandle, $params['content'] );
$created = ( $bytes === strlen( $params['content'] ) );
fclose( $stageHandle );
$created = $created ? rename( $fsStagePath, $fsDstPath ) : false;
}
$hadError = $this->untrapWarnings();
if ( $hadError || !$created ) {
$status->fatal( 'backend-fail-create', $params['dst'] );
return $status;
}
$this->chmod( $fsDstPath );
}
return $status;
}
protected function doStoreInternal( array $params ) {
$status = $this->newStatus();
$fsSrcPath = $params['src']; // file system path
$fsDstPath = $this->resolveToFSPath( $params['dst'] );
if ( $fsDstPath === null ) {
$status->fatal( 'backend-fail-invalidpath', $params['dst'] );
return $status;
}
if ( $fsSrcPath === $fsDstPath ) {
$status->fatal( 'backend-fail-internal', $this->name );
return $status;
}
if ( !empty( $params['async'] ) ) { // deferred
$cmd = $this->makeCopyCommand( $fsSrcPath, $fsDstPath, false );
$handler = function ( $errors, StatusValue $status, array $params, $cmd ) {
if ( $errors !== '' && !( $this->os === 'Windows' && $errors[0] === " " ) ) {
$status->fatal( 'backend-fail-store', $params['src'], $params['dst'] );
trigger_error( "$cmd\n$errors", E_USER_WARNING ); // command output
}
};
$status->value = new FSFileOpHandle( $this, $params, $handler, $cmd );
} else { // immediate write
$stored = false;
// Use fwrite+rename since (a) this clears xattrs, (b) threads still reading the old
// inode are unaffected since it writes to a new inode, and (c) new threads reading
// the file will either totally see the old version or totally see the new version
$fsStagePath = $this->makeStagingPath( $fsDstPath );
$this->trapWarningsIgnoringNotFound();
$srcHandle = fopen( $fsSrcPath, 'rb' );
if ( $srcHandle ) {
$stageHandle = fopen( $fsStagePath, 'xb' );
if ( $stageHandle ) {
$bytes = stream_copy_to_stream( $srcHandle, $stageHandle );
$stored = ( $bytes !== false && $bytes === fstat( $srcHandle )['size'] );
fclose( $stageHandle );
$stored = $stored ? rename( $fsStagePath, $fsDstPath ) : false;
}
fclose( $srcHandle );
}
$hadError = $this->untrapWarnings();
if ( $hadError || !$stored ) {
$status->fatal( 'backend-fail-store', $params['src'], $params['dst'] );
return $status;
}
$this->chmod( $fsDstPath );
}
return $status;
}
protected function doCopyInternal( array $params ) {
$status = $this->newStatus();
$fsSrcPath = $this->resolveToFSPath( $params['src'] );
if ( $fsSrcPath === null ) {
$status->fatal( 'backend-fail-invalidpath', $params['src'] );
return $status;
}
$fsDstPath = $this->resolveToFSPath( $params['dst'] );
if ( $fsDstPath === null ) {
$status->fatal( 'backend-fail-invalidpath', $params['dst'] );
return $status;
}
if ( $fsSrcPath === $fsDstPath ) {
return $status; // no-op
}
$ignoreMissing = !empty( $params['ignoreMissingSource'] );
if ( !empty( $params['async'] ) ) { // deferred
$cmd = $this->makeCopyCommand( $fsSrcPath, $fsDstPath, $ignoreMissing );
$handler = function ( $errors, StatusValue $status, array $params, $cmd ) {
if ( $errors !== '' && !( $this->os === 'Windows' && $errors[0] === " " ) ) {
$status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
trigger_error( "$cmd\n$errors", E_USER_WARNING ); // command output
}
};
$status->value = new FSFileOpHandle( $this, $params, $handler, $cmd );
} else { // immediate write
$copied = false;
// Use fwrite+rename since (a) this clears xattrs, (b) threads still reading the old
// inode are unaffected since it writes to a new inode, and (c) new threads reading
// the file will either totally see the old version or totally see the new version
$fsStagePath = $this->makeStagingPath( $fsDstPath );
$this->trapWarningsIgnoringNotFound();
$srcHandle = fopen( $fsSrcPath, 'rb' );
if ( $srcHandle ) {
$stageHandle = fopen( $fsStagePath, 'xb' );
if ( $stageHandle ) {
$bytes = stream_copy_to_stream( $srcHandle, $stageHandle );
$copied = ( $bytes !== false && $bytes === fstat( $srcHandle )['size'] );
fclose( $stageHandle );
$copied = $copied ? rename( $fsStagePath, $fsDstPath ) : false;
}
fclose( $srcHandle );
}
$hadError = $this->untrapWarnings();
if ( $hadError || ( !$copied && !$ignoreMissing ) ) {
$status->fatal( 'backend-fail-copy', $params['src'], $params['dst'] );
return $status;
}
if ( $copied ) {
$this->chmod( $fsDstPath );
}
}
return $status;
}
protected function doMoveInternal( array $params ) {
$status = $this->newStatus();
$fsSrcPath = $this->resolveToFSPath( $params['src'] );
if ( $fsSrcPath === null ) {
$status->fatal( 'backend-fail-invalidpath', $params['src'] );
return $status;
}
$fsDstPath = $this->resolveToFSPath( $params['dst'] );
if ( $fsDstPath === null ) {
$status->fatal( 'backend-fail-invalidpath', $params['dst'] );
return $status;
}
if ( $fsSrcPath === $fsDstPath ) {
return $status; // no-op
}
$ignoreMissing = !empty( $params['ignoreMissingSource'] );
if ( !empty( $params['async'] ) ) { // deferred
$cmd = $this->makeMoveCommand( $fsSrcPath, $fsDstPath, $ignoreMissing );
$handler = function ( $errors, StatusValue $status, array $params, $cmd ) {
if ( $errors !== '' && !( $this->os === 'Windows' && $errors[0] === " " ) ) {
$status->fatal( 'backend-fail-move', $params['src'], $params['dst'] );
trigger_error( "$cmd\n$errors", E_USER_WARNING ); // command output
}
};
$status->value = new FSFileOpHandle( $this, $params, $handler, $cmd );
} else { // immediate write
// Use rename() here since (a) this clears xattrs, (b) any threads still reading the
// old inode are unaffected since it writes to a new inode, and (c) this is fast and
// atomic within a file system volume (as is normally the case)
$this->trapWarningsIgnoringNotFound();
$moved = rename( $fsSrcPath, $fsDstPath );
$hadError = $this->untrapWarnings();
if ( $hadError || ( !$moved && !$ignoreMissing ) ) {
$status->fatal( 'backend-fail-move', $params['src'], $params['dst'] );
return $status;
}
}
return $status;
}
protected function doDeleteInternal( array $params ) {
$status = $this->newStatus();
$fsSrcPath = $this->resolveToFSPath( $params['src'] );
if ( $fsSrcPath === null ) {
$status->fatal( 'backend-fail-invalidpath', $params['src'] );
return $status;
}
$ignoreMissing = !empty( $params['ignoreMissingSource'] );
if ( !empty( $params['async'] ) ) { // deferred
$cmd = $this->makeUnlinkCommand( $fsSrcPath, $ignoreMissing );
$handler = function ( $errors, StatusValue $status, array $params, $cmd ) {
if ( $errors !== '' && !( $this->os === 'Windows' && $errors[0] === " " ) ) {
$status->fatal( 'backend-fail-delete', $params['src'] );
trigger_error( "$cmd\n$errors", E_USER_WARNING ); // command output
}
};
$status->value = new FSFileOpHandle( $this, $params, $handler, $cmd );
} else { // immediate write
$this->trapWarningsIgnoringNotFound();
$deleted = unlink( $fsSrcPath );
$hadError = $this->untrapWarnings();
if ( $hadError || ( !$deleted && !$ignoreMissing ) ) {
$status->fatal( 'backend-fail-delete', $params['src'] );
return $status;
}
}
return $status;
}
/**
* @inheritDoc
*/
protected function doPrepareInternal( $fullCont, $dirRel, array $params ) {
$status = $this->newStatus();
[ , $shortCont, ] = FileBackend::splitStoragePath( $params['dir'] );
$contRoot = $this->containerFSRoot( $shortCont, $fullCont ); // must be valid
$fsDirectory = ( $dirRel != '' ) ? "{$contRoot}/{$dirRel}" : $contRoot;
// Create the directory and its parents as needed...
$created = false;
AtEase::suppressWarnings();
$alreadyExisted = is_dir( $fsDirectory ); // already there?
if ( !$alreadyExisted ) {
$created = mkdir( $fsDirectory, $this->dirMode, true );
if ( !$created ) {
$alreadyExisted = is_dir( $fsDirectory ); // another thread made it?
}
}
$isWritable = $created ?: is_writable( $fsDirectory ); // assume writable if created here
AtEase::restoreWarnings();
if ( !$alreadyExisted && !$created ) {
$this->logger->error( __METHOD__ . ": cannot create directory $fsDirectory" );
$status->fatal( 'directorycreateerror', $params['dir'] ); // fails on races
} elseif ( !$isWritable ) {
$this->logger->error( __METHOD__ . ": directory $fsDirectory is read-only" );
$status->fatal( 'directoryreadonlyerror', $params['dir'] );
}
// Respect any 'noAccess' or 'noListing' flags...
if ( $created ) {
$status->merge( $this->doSecureInternal( $fullCont, $dirRel, $params ) );
}
if ( $status->isGood() ) {
$this->usableDirCache->set( $fsDirectory, 1 );
}
return $status;
}
protected function doSecureInternal( $fullCont, $dirRel, array $params ) {
$status = $this->newStatus();
[ , $shortCont, ] = FileBackend::splitStoragePath( $params['dir'] );
$contRoot = $this->containerFSRoot( $shortCont, $fullCont ); // must be valid
$fsDirectory = ( $dirRel != '' ) ? "{$contRoot}/{$dirRel}" : $contRoot;
// Seed new directories with a blank index.html, to prevent crawling...
if ( !empty( $params['noListing'] ) && !is_file( "{$fsDirectory}/index.html" ) ) {
$this->trapWarnings();
$bytes = file_put_contents( "{$fsDirectory}/index.html", $this->indexHtmlPrivate() );
$this->untrapWarnings();
if ( $bytes === false ) {
$status->fatal( 'backend-fail-create', $params['dir'] . '/index.html' );
}
}
// Add a .htaccess file to the root of the container...
if ( !empty( $params['noAccess'] ) && !is_file( "{$contRoot}/.htaccess" ) ) {
AtEase::suppressWarnings();
$bytes = file_put_contents( "{$contRoot}/.htaccess", $this->htaccessPrivate() );
AtEase::restoreWarnings();
if ( $bytes === false ) {
$storeDir = "mwstore://{$this->name}/{$shortCont}";
$status->fatal( 'backend-fail-create', "{$storeDir}/.htaccess" );
}
}
return $status;
}
protected function doPublishInternal( $fullCont, $dirRel, array $params ) {
$status = $this->newStatus();
[ , $shortCont, ] = FileBackend::splitStoragePath( $params['dir'] );
$contRoot = $this->containerFSRoot( $shortCont, $fullCont ); // must be valid
$fsDirectory = ( $dirRel != '' ) ? "{$contRoot}/{$dirRel}" : $contRoot;
// Unseed new directories with a blank index.html, to allow crawling...
if ( !empty( $params['listing'] ) && is_file( "{$fsDirectory}/index.html" ) ) {
$exists = ( file_get_contents( "{$fsDirectory}/index.html" ) === $this->indexHtmlPrivate() );
if ( $exists && !$this->unlink( "{$fsDirectory}/index.html" ) ) { // reverse secure()
$status->fatal( 'backend-fail-delete', $params['dir'] . '/index.html' );
}
}
// Remove the .htaccess file from the root of the container...
if ( !empty( $params['access'] ) && is_file( "{$contRoot}/.htaccess" ) ) {
$exists = ( file_get_contents( "{$contRoot}/.htaccess" ) === $this->htaccessPrivate() );
if ( $exists && !$this->unlink( "{$contRoot}/.htaccess" ) ) { // reverse secure()
$storeDir = "mwstore://{$this->name}/{$shortCont}";
$status->fatal( 'backend-fail-delete', "{$storeDir}/.htaccess" );
}
}
return $status;
}
protected function doCleanInternal( $fullCont, $dirRel, array $params ) {
$status = $this->newStatus();
[ , $shortCont, ] = FileBackend::splitStoragePath( $params['dir'] );
$contRoot = $this->containerFSRoot( $shortCont, $fullCont ); // must be valid
$fsDirectory = ( $dirRel != '' ) ? "{$contRoot}/{$dirRel}" : $contRoot;
$this->rmdir( $fsDirectory );
return $status;
}
protected function doGetFileStat( array $params ) {
$fsSrcPath = $this->resolveToFSPath( $params['src'] );
if ( $fsSrcPath === null ) {
return self::RES_ERROR; // invalid storage path
}
$this->trapWarnings(); // don't trust 'false' if there were errors
$stat = is_file( $fsSrcPath ) ? stat( $fsSrcPath ) : false; // regular files only
$hadError = $this->untrapWarnings();
if ( is_array( $stat ) ) {
$ct = new ConvertibleTimestamp( $stat['mtime'] );
return [
'mtime' => $ct->getTimestamp( TS_MW ),
'size' => $stat['size']
];
}
return $hadError ? self::RES_ERROR : self::RES_ABSENT;
}
protected function doClearCache( array $paths = null ) {
if ( is_array( $paths ) ) {
foreach ( $paths as $path ) {
$fsPath = $this->resolveToFSPath( $path );
if ( $fsPath !== null ) {
clearstatcache( true, $fsPath );
$this->usableDirCache->clear( $fsPath );
}
}
} else {
clearstatcache( true ); // clear the PHP file stat cache
$this->usableDirCache->clear();
}
}
protected function doDirectoryExists( $fullCont, $dirRel, array $params ) {
[ , $shortCont, ] = FileBackend::splitStoragePath( $params['dir'] );
$contRoot = $this->containerFSRoot( $shortCont, $fullCont ); // must be valid
$fsDirectory = ( $dirRel != '' ) ? "{$contRoot}/{$dirRel}" : $contRoot;
$this->trapWarnings(); // don't trust 'false' if there were errors
$exists = is_dir( $fsDirectory );
$hadError = $this->untrapWarnings();
return $hadError ? self::RES_ERROR : $exists;
}
/**
* @see FileBackendStore::getDirectoryListInternal()
* @param string $fullCont
* @param string $dirRel
* @param array $params
* @return array|FSFileBackendDirList|null
*/
public function getDirectoryListInternal( $fullCont, $dirRel, array $params ) {
[ , $shortCont, ] = FileBackend::splitStoragePath( $params['dir'] );
$contRoot = $this->containerFSRoot( $shortCont, $fullCont ); // must be valid
$fsDirectory = ( $dirRel != '' ) ? "{$contRoot}/{$dirRel}" : $contRoot;
$list = new FSFileBackendDirList( $fsDirectory, $params );
$error = $list->getLastError();
if ( $error !== null ) {
if ( $this->isFileNotFoundError( $error ) ) {
$this->logger->info( __METHOD__ . ": non-existant directory: '$fsDirectory'" );
return []; // nothing under this dir
} elseif ( is_dir( $fsDirectory ) ) {
$this->logger->warning( __METHOD__ . ": unreadable directory: '$fsDirectory'" );
return self::RES_ERROR; // bad permissions?
} else {
$this->logger->warning( __METHOD__ . ": unreachable directory: '$fsDirectory'" );
return self::RES_ERROR;
}
}
return $list;
}
/**
* @see FileBackendStore::getFileListInternal()
* @param string $fullCont
* @param string $dirRel
* @param array $params
* @return array|FSFileBackendFileList|null
*/
public function getFileListInternal( $fullCont, $dirRel, array $params ) {
[ , $shortCont, ] = FileBackend::splitStoragePath( $params['dir'] );
$contRoot = $this->containerFSRoot( $shortCont, $fullCont ); // must be valid
$fsDirectory = ( $dirRel != '' ) ? "{$contRoot}/{$dirRel}" : $contRoot;
$list = new FSFileBackendFileList( $fsDirectory, $params );
$error = $list->getLastError();
if ( $error !== null ) {
if ( $this->isFileNotFoundError( $error ) ) {
$this->logger->info( __METHOD__ . ": non-existent directory: '$fsDirectory'" );
return []; // nothing under this dir
} elseif ( is_dir( $fsDirectory ) ) {
$this->logger->warning( __METHOD__ .
": unreadable directory: '$fsDirectory': $error" );
return self::RES_ERROR; // bad permissions?
} else {
$this->logger->warning( __METHOD__ .
": unreachable directory: '$fsDirectory': $error" );
return self::RES_ERROR;
}
}
return $list;
}
protected function doGetLocalReferenceMulti( array $params ) {
$fsFiles = []; // (path => FSFile)
foreach ( $params['srcs'] as $src ) {
$source = $this->resolveToFSPath( $src );
if ( $source === null ) {
$fsFiles[$src] = self::RES_ERROR; // invalid path
continue;
}
$this->trapWarnings(); // don't trust 'false' if there were errors
$isFile = is_file( $source ); // regular files only
$hadError = $this->untrapWarnings();
if ( $isFile ) {
$fsFiles[$src] = new FSFile( $source );
} elseif ( $hadError ) {
$fsFiles[$src] = self::RES_ERROR;
} else {
$fsFiles[$src] = self::RES_ABSENT;
}
}
return $fsFiles;
}
protected function doGetLocalCopyMulti( array $params ) {
$tmpFiles = []; // (path => TempFSFile)
foreach ( $params['srcs'] as $src ) {
$source = $this->resolveToFSPath( $src );
if ( $source === null ) {
$tmpFiles[$src] = self::RES_ERROR; // invalid path
continue;
}
// Create a new temporary file with the same extension...
$ext = FileBackend::extensionFromPath( $src );
$tmpFile = $this->tmpFileFactory->newTempFSFile( 'localcopy_', $ext );
if ( !$tmpFile ) {
$tmpFiles[$src] = self::RES_ERROR;
continue;
}
$tmpPath = $tmpFile->getPath();
// Copy the source file over the temp file
$this->trapWarnings(); // don't trust 'false' if there were errors
$isFile = is_file( $source ); // regular files only
$copySuccess = $isFile ? copy( $source, $tmpPath ) : false;
$hadError = $this->untrapWarnings();
if ( $copySuccess ) {
$this->chmod( $tmpPath );
$tmpFiles[$src] = $tmpFile;
} elseif ( $hadError ) {
$tmpFiles[$src] = self::RES_ERROR; // copy failed
} else {
$tmpFiles[$src] = self::RES_ABSENT;
}
}
return $tmpFiles;
}
protected function directoriesAreVirtual() {
return false;
}
/**
* @param FSFileOpHandle[] $fileOpHandles
*
* @return StatusValue[]
*/
protected function doExecuteOpHandlesInternal( array $fileOpHandles ) {
$statuses = [];
$pipes = [];
foreach ( $fileOpHandles as $index => $fileOpHandle ) {
$pipes[$index] = popen( $fileOpHandle->cmd, 'r' );
}
$errs = [];
foreach ( $pipes as $index => $pipe ) {
// Result will be empty on success in *NIX. On Windows,
// it may be something like " 1 file(s) [copied|moved].".
$errs[$index] = stream_get_contents( $pipe );
fclose( $pipe );
}
foreach ( $fileOpHandles as $index => $fileOpHandle ) {
$status = $this->newStatus();
$function = $fileOpHandle->callback;
$function( $errs[$index], $status, $fileOpHandle->params, $fileOpHandle->cmd );
$statuses[$index] = $status;
}
return $statuses;
}
/**
* @param string $fsPath Absolute file system path
* @return string Absolute file system path on the same device
*/
private function makeStagingPath( $fsPath ) {
$time = dechex( time() ); // make it easy to find old orphans
$hash = \Wikimedia\base_convert( md5( basename( $fsPath ) ), 16, 36, 25 );
$unique = \Wikimedia\base_convert( bin2hex( random_bytes( 16 ) ), 16, 36, 25 );
return dirname( $fsPath ) . "/.{$time}_{$hash}_{$unique}.tmpfsfile";
}
/**
* @param string $fsSrcPath Absolute file system path
* @param string $fsDstPath Absolute file system path
* @param bool $ignoreMissing Whether to no-op if the source file is non-existent
* @return string Command
*/
private function makeCopyCommand( $fsSrcPath, $fsDstPath, $ignoreMissing ) {
// Use copy+rename since (a) this clears xattrs, (b) threads still reading the old
// inode are unaffected since it writes to a new inode, and (c) new threads reading
// the file will either totally see the old version or totally see the new version
$fsStagePath = $this->makeStagingPath( $fsDstPath );
$encSrc = Shellbox::escape( $this->cleanPathSlashes( $fsSrcPath ) );
$encStage = Shellbox::escape( $this->cleanPathSlashes( $fsStagePath ) );
$encDst = Shellbox::escape( $this->cleanPathSlashes( $fsDstPath ) );
if ( $this->os === 'Windows' ) {
// https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/copy
// https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/move
$cmdWrite = "COPY /B /Y $encSrc $encStage 2>&1 && MOVE /Y $encStage $encDst 2>&1";
$cmd = $ignoreMissing ? "IF EXIST $encSrc $cmdWrite" : $cmdWrite;
} else {
// https://manpages.debian.org/buster/coreutils/cp.1.en.html
// https://manpages.debian.org/buster/coreutils/mv.1.en.html
$cmdWrite = "cp $encSrc $encStage 2>&1 && mv $encStage $encDst 2>&1";
$cmd = $ignoreMissing ? "test -f $encSrc && $cmdWrite" : $cmdWrite;
// Clean up permissions on any newly created destination file
$octalPermissions = '0' . decoct( $this->fileMode );
if ( strlen( $octalPermissions ) == 4 ) {
$cmd .= " && chmod $octalPermissions $encDst 2>/dev/null";
}
}
return $cmd;
}
/**
* @param string $fsSrcPath Absolute file system path
* @param string $fsDstPath Absolute file system path
* @param bool $ignoreMissing Whether to no-op if the source file is non-existent
* @return string Command
*/
private function makeMoveCommand( $fsSrcPath, $fsDstPath, $ignoreMissing = false ) {
// https://manpages.debian.org/buster/coreutils/mv.1.en.html
// https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/move
$encSrc = Shellbox::escape( $this->cleanPathSlashes( $fsSrcPath ) );
$encDst = Shellbox::escape( $this->cleanPathSlashes( $fsDstPath ) );
if ( $this->os === 'Windows' ) {
$writeCmd = "MOVE /Y $encSrc $encDst 2>&1";
$cmd = $ignoreMissing ? "IF EXIST $encSrc $writeCmd" : $writeCmd;
} else {
$writeCmd = "mv -f $encSrc $encDst 2>&1";
$cmd = $ignoreMissing ? "test -f $encSrc && $writeCmd" : $writeCmd;
}
return $cmd;
}
/**
* @param string $fsPath Absolute file system path
* @param bool $ignoreMissing Whether to no-op if the file is non-existent
* @return string Command
*/
private function makeUnlinkCommand( $fsPath, $ignoreMissing = false ) {
// https://manpages.debian.org/buster/coreutils/rm.1.en.html
// https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/del
$encSrc = Shellbox::escape( $this->cleanPathSlashes( $fsPath ) );
if ( $this->os === 'Windows' ) {
$writeCmd = "DEL /Q $encSrc 2>&1";
$cmd = $ignoreMissing ? "IF EXIST $encSrc $writeCmd" : $writeCmd;
} else {
$cmd = $ignoreMissing ? "rm -f $encSrc 2>&1" : "rm $encSrc 2>&1";
}
return $cmd;
}
/**
* Chmod a file, suppressing the warnings
*
* @param string $fsPath Absolute file system path
* @return bool Success
*/
protected function chmod( $fsPath ) {
if ( $this->os === 'Windows' ) {
return true;
}
AtEase::suppressWarnings();
$ok = chmod( $fsPath, $this->fileMode );
AtEase::restoreWarnings();
return $ok;
}
/**
* Unlink a file, suppressing the warnings
*
* @param string $fsPath Absolute file system path
* @return bool Success
*/
protected function unlink( $fsPath ) {
AtEase::suppressWarnings();
$ok = unlink( $fsPath );
AtEase::restoreWarnings();
clearstatcache( true, $fsPath );
return $ok;
}
/**
* Remove an empty directory, suppressing the warnings
*
* @param string $fsDirectory Absolute file system path
* @return bool Success
*/
protected function rmdir( $fsDirectory ) {
AtEase::suppressWarnings();
$ok = rmdir( $fsDirectory ); // remove directory if empty
AtEase::restoreWarnings();
clearstatcache( true, $fsDirectory );
return $ok;
}
/**
* @param array $params Parameters for FileBackend 'create' operation
* @return TempFSFile|null
*/
protected function newTempFileWithContent( array $params ) {
$tempFile = $this->tmpFileFactory->newTempFSFile( 'create_', 'tmp' );
if ( !$tempFile ) {
return null;
}
AtEase::suppressWarnings();
if ( file_put_contents( $tempFile->getPath(), $params['content'] ) === false ) {
$tempFile = null;
}
AtEase::restoreWarnings();
return $tempFile;
}
/**
* Return the text of an index.html file to hide directory listings
*
* @return string
*/
protected function indexHtmlPrivate() {
return '';
}
/**
* Return the text of a .htaccess file to make a directory private
*
* @return string
*/
protected function htaccessPrivate() {
return "Require all denied\n";
}
/**
* Clean up directory separators for the given OS
*
* @param string $fsPath
* @return string
*/
protected function cleanPathSlashes( $fsPath ) {
return ( $this->os === 'Windows' ) ? strtr( $fsPath, '/', '\\' ) : $fsPath;
}
/**
* Listen for E_WARNING errors and track whether any that happen
*
* @param string|null $regexIgnore Optional regex of errors to ignore
*/
protected function trapWarnings( $regexIgnore = null ) {
$this->warningTrapStack[] = false;
set_error_handler( function ( $errno, $errstr ) use ( $regexIgnore ) {
if ( $regexIgnore === null || !preg_match( $regexIgnore, $errstr ) ) {
$this->logger->error( $errstr );
$this->warningTrapStack[count( $this->warningTrapStack ) - 1] = true;
}
return true; // suppress from PHP handler
}, E_WARNING );
}
/**
* Track E_WARNING errors but ignore any that correspond to ENOENT "No such file or directory"
*/
protected function trapWarningsIgnoringNotFound() {
$this->trapWarnings( $this->getFileNotFoundRegex() );
}
/**
* Stop listening for E_WARNING errors and get whether any happened
*
* @return bool Whether any warnings happened
*/
protected function untrapWarnings() {
restore_error_handler();
return array_pop( $this->warningTrapStack );
}
/**
* Get a regex matching file not found errors
*
* @return string
*/
protected function getFileNotFoundRegex() {
static $regex;
if ( $regex === null ) {
// "No such file or directory": string literal in spl_directory.c etc.
$alternatives = [ ': No such file or directory' ];
if ( $this->os === 'Windows' ) {
// 2 = The system cannot find the file specified.
// 3 = The system cannot find the path specified.
$alternatives[] = ' \(code: [23]\)';
}
if ( function_exists( 'pcntl_strerror' ) ) {
$alternatives[] = preg_quote( ': ' . pcntl_strerror( 2 ), '/' );
} elseif ( function_exists( 'socket_strerror' ) && defined( 'SOCKET_ENOENT' ) ) {
$alternatives[] = preg_quote( ': ' . socket_strerror( SOCKET_ENOENT ), '/' );
}
$regex = '/(' . implode( '|', $alternatives ) . ')$/';
}
return $regex;
}
/**
* Determine whether a given error message is a file not found error.
*
* @param string $error
* @return bool
*/
protected function isFileNotFoundError( $error ) {
return (bool)preg_match( $this->getFileNotFoundRegex(), $error );
}
}