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Diffstat (limited to 'www/wiki/includes/libs/filebackend/FileBackend.php')
| -rw-r--r-- | www/wiki/includes/libs/filebackend/FileBackend.php | 1638 |
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diff --git a/www/wiki/includes/libs/filebackend/FileBackend.php b/www/wiki/includes/libs/filebackend/FileBackend.php new file mode 100644 index 00000000..08f960a6 --- /dev/null +++ b/www/wiki/includes/libs/filebackend/FileBackend.php @@ -0,0 +1,1638 @@ +<?php +/** + * @defgroup FileBackend File backend + * + * File backend is used to interact with file storage systems, + * such as the local file system, NFS, or cloud storage systems. + */ + +/** + * Base class for all file backends. + * + * 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 Psr\Log\LoggerAwareInterface; +use Psr\Log\LoggerInterface; +use Wikimedia\ScopedCallback; + +/** + * @brief Base class for all file backend classes (including multi-write backends). + * + * This class defines the methods as abstract that subclasses must implement. + * Outside callers can assume that all backends will have these functions. + * + * All "storage paths" are of the format "mwstore://<backend>/<container>/<path>". + * The "backend" portion is unique name for the application to refer to a backend, while + * the "container" portion is a top-level directory of the backend. The "path" portion + * is a relative path that uses UNIX file system (FS) notation, though any particular + * backend may not actually be using a local filesystem. Therefore, the relative paths + * are only virtual. + * + * Backend contents are stored under "domain"-specific container names by default. + * A domain is simply a logical umbrella for entities, such as those belonging to a certain + * application or portion of a website, for example. A domain can be local or global. + * Global (qualified) backends are achieved by configuring the "domain ID" to a constant. + * Global domains are simpler, but local domains can be used by choosing a domain ID based on + * the current context, such as which language of a website is being used. + * + * For legacy reasons, the FSFileBackend class allows manually setting the paths of + * containers to ones that do not respect the "domain ID". + * + * In key/value (object) stores, containers are the only hierarchy (the rest is emulated). + * FS-based backends are somewhat more restrictive due to the existence of real + * directory files; a regular file cannot have the same name as a directory. Other + * backends with virtual directories may not have this limitation. Callers should + * store files in such a way that no files and directories are under the same path. + * + * In general, this class allows for callers to access storage through the same + * interface, without regard to the underlying storage system. However, calling code + * must follow certain patterns and be aware of certain things to ensure compatibility: + * - a) Always call prepare() on the parent directory before trying to put a file there; + * key/value stores only need the container to exist first, but filesystems need + * all the parent directories to exist first (prepare() is aware of all this) + * - b) Always call clean() on a directory when it might become empty to avoid empty + * directory buildup on filesystems; key/value stores never have empty directories, + * so doing this helps preserve consistency in both cases + * - c) Likewise, do not rely on the existence of empty directories for anything; + * calling directoryExists() on a path that prepare() was previously called on + * will return false for key/value stores if there are no files under that path + * - d) Never alter the resulting FSFile returned from getLocalReference(), as it could + * either be a copy of the source file in /tmp or the original source file itself + * - e) Use a file layout that results in never attempting to store files over directories + * or directories over files; key/value stores allow this but filesystems do not + * - f) Use ASCII file names (e.g. base32, IDs, hashes) to avoid Unicode issues in Windows + * - g) Do not assume that move operations are atomic (difficult with key/value stores) + * - h) Do not assume that file stat or read operations always have immediate consistency; + * various methods have a "latest" flag that should always be used if up-to-date + * information is required (this trades performance for correctness as needed) + * - i) Do not assume that directory listings have immediate consistency + * + * Methods of subclasses should avoid throwing exceptions at all costs. + * As a corollary, external dependencies should be kept to a minimum. + * + * @ingroup FileBackend + * @since 1.19 + */ +abstract class FileBackend implements LoggerAwareInterface { + /** @var string Unique backend name */ + protected $name; + + /** @var string Unique domain name */ + protected $domainId; + + /** @var string Read-only explanation message */ + protected $readOnly; + + /** @var string When to do operations in parallel */ + protected $parallelize; + + /** @var int How many operations can be done in parallel */ + protected $concurrency; + + /** @var string Temporary file directory */ + protected $tmpDirectory; + + /** @var LockManager */ + protected $lockManager; + /** @var FileJournal */ + protected $fileJournal; + /** @var LoggerInterface */ + protected $logger; + /** @var object|string Class name or object With profileIn/profileOut methods */ + protected $profiler; + + /** @var callable */ + protected $obResetFunc; + /** @var callable */ + protected $streamMimeFunc; + /** @var callable */ + protected $statusWrapper; + + /** Bitfield flags for supported features */ + const ATTR_HEADERS = 1; // files can be tagged with standard HTTP headers + const ATTR_METADATA = 2; // files can be stored with metadata key/values + const ATTR_UNICODE_PATHS = 4; // files can have Unicode paths (not just ASCII) + + /** + * Create a new backend instance from configuration. + * This should only be called from within FileBackendGroup. + * + * @param array $config Parameters include: + * - name : The unique name of this backend. + * This should consist of alphanumberic, '-', and '_' characters. + * This name should not be changed after use (e.g. with journaling). + * Note that the name is *not* used in actual container names. + * - domainId : Prefix to container names that is unique to this backend. + * It should only consist of alphanumberic, '-', and '_' characters. + * This ID is what avoids collisions if multiple logical backends + * use the same storage system, so this should be set carefully. + * - lockManager : LockManager object to use for any file locking. + * If not provided, then no file locking will be enforced. + * - fileJournal : FileJournal object to use for logging changes to files. + * If not provided, then change journaling will be disabled. + * - readOnly : Write operations are disallowed if this is a non-empty string. + * It should be an explanation for the backend being read-only. + * - parallelize : When to do file operations in parallel (when possible). + * Allowed values are "implicit", "explicit" and "off". + * - concurrency : How many file operations can be done in parallel. + * - tmpDirectory : Directory to use for temporary files. If this is not set or null, + * then the backend will try to discover a usable temporary directory. + * - obResetFunc : alternative callback to clear the output buffer + * - streamMimeFunc : alternative method to determine the content type from the path + * - logger : Optional PSR logger object. + * - profiler : Optional class name or object With profileIn/profileOut methods. + * @throws InvalidArgumentException + */ + public function __construct( array $config ) { + $this->name = $config['name']; + $this->domainId = isset( $config['domainId'] ) + ? $config['domainId'] // e.g. "my_wiki-en_" + : $config['wikiId']; // b/c alias + if ( !preg_match( '!^[a-zA-Z0-9-_]{1,255}$!', $this->name ) ) { + throw new InvalidArgumentException( "Backend name '{$this->name}' is invalid." ); + } elseif ( !is_string( $this->domainId ) ) { + throw new InvalidArgumentException( + "Backend domain ID not provided for '{$this->name}'." ); + } + $this->lockManager = isset( $config['lockManager'] ) + ? $config['lockManager'] + : new NullLockManager( [] ); + $this->fileJournal = isset( $config['fileJournal'] ) + ? $config['fileJournal'] + : FileJournal::factory( [ 'class' => NullFileJournal::class ], $this->name ); + $this->readOnly = isset( $config['readOnly'] ) + ? (string)$config['readOnly'] + : ''; + $this->parallelize = isset( $config['parallelize'] ) + ? (string)$config['parallelize'] + : 'off'; + $this->concurrency = isset( $config['concurrency'] ) + ? (int)$config['concurrency'] + : 50; + $this->obResetFunc = isset( $config['obResetFunc'] ) + ? $config['obResetFunc'] + : [ $this, 'resetOutputBuffer' ]; + $this->streamMimeFunc = isset( $config['streamMimeFunc'] ) + ? $config['streamMimeFunc'] + : null; + $this->statusWrapper = isset( $config['statusWrapper'] ) ? $config['statusWrapper'] : null; + + $this->profiler = isset( $config['profiler'] ) ? $config['profiler'] : null; + $this->logger = isset( $config['logger'] ) ? $config['logger'] : new \Psr\Log\NullLogger(); + $this->statusWrapper = isset( $config['statusWrapper'] ) ? $config['statusWrapper'] : null; + $this->tmpDirectory = isset( $config['tmpDirectory'] ) ? $config['tmpDirectory'] : null; + } + + public function setLogger( LoggerInterface $logger ) { + $this->logger = $logger; + } + + /** + * Get the unique backend name. + * We may have multiple different backends of the same type. + * For example, we can have two Swift backends using different proxies. + * + * @return string + */ + final public function getName() { + return $this->name; + } + + /** + * Get the domain identifier used for this backend (possibly empty). + * + * @return string + * @since 1.28 + */ + final public function getDomainId() { + return $this->domainId; + } + + /** + * Alias to getDomainId() + * @return string + * @since 1.20 + */ + final public function getWikiId() { + return $this->getDomainId(); + } + + /** + * Check if this backend is read-only + * + * @return bool + */ + final public function isReadOnly() { + return ( $this->readOnly != '' ); + } + + /** + * Get an explanatory message if this backend is read-only + * + * @return string|bool Returns false if the backend is not read-only + */ + final public function getReadOnlyReason() { + return ( $this->readOnly != '' ) ? $this->readOnly : false; + } + + /** + * Get the a bitfield of extra features supported by the backend medium + * + * @return int Bitfield of FileBackend::ATTR_* flags + * @since 1.23 + */ + public function getFeatures() { + return self::ATTR_UNICODE_PATHS; + } + + /** + * Check if the backend medium supports a field of extra features + * + * @param int $bitfield Bitfield of FileBackend::ATTR_* flags + * @return bool + * @since 1.23 + */ + final public function hasFeatures( $bitfield ) { + return ( $this->getFeatures() & $bitfield ) === $bitfield; + } + + /** + * This is the main entry point into the backend for write operations. + * Callers supply an ordered list of operations to perform as a transaction. + * Files will be locked, the stat cache cleared, and then the operations attempted. + * If any serious errors occur, all attempted operations will be rolled back. + * + * $ops is an array of arrays. The outer array holds a list of operations. + * Each inner array is a set of key value pairs that specify an operation. + * + * Supported operations and their parameters. The supported actions are: + * - create + * - store + * - copy + * - move + * - delete + * - describe (since 1.21) + * - null + * + * FSFile/TempFSFile object support was added in 1.27. + * + * a) Create a new file in storage with the contents of a string + * @code + * [ + * 'op' => 'create', + * 'dst' => <storage path>, + * 'content' => <string of new file contents>, + * 'overwrite' => <boolean>, + * 'overwriteSame' => <boolean>, + * 'headers' => <HTTP header name/value map> # since 1.21 + * ] + * @endcode + * + * b) Copy a file system file into storage + * @code + * [ + * 'op' => 'store', + * 'src' => <file system path, FSFile, or TempFSFile>, + * 'dst' => <storage path>, + * 'overwrite' => <boolean>, + * 'overwriteSame' => <boolean>, + * 'headers' => <HTTP header name/value map> # since 1.21 + * ] + * @endcode + * + * c) Copy a file within storage + * @code + * [ + * 'op' => 'copy', + * 'src' => <storage path>, + * 'dst' => <storage path>, + * 'overwrite' => <boolean>, + * 'overwriteSame' => <boolean>, + * 'ignoreMissingSource' => <boolean>, # since 1.21 + * 'headers' => <HTTP header name/value map> # since 1.21 + * ] + * @endcode + * + * d) Move a file within storage + * @code + * [ + * 'op' => 'move', + * 'src' => <storage path>, + * 'dst' => <storage path>, + * 'overwrite' => <boolean>, + * 'overwriteSame' => <boolean>, + * 'ignoreMissingSource' => <boolean>, # since 1.21 + * 'headers' => <HTTP header name/value map> # since 1.21 + * ] + * @endcode + * + * e) Delete a file within storage + * @code + * [ + * 'op' => 'delete', + * 'src' => <storage path>, + * 'ignoreMissingSource' => <boolean> + * ] + * @endcode + * + * f) Update metadata for a file within storage + * @code + * [ + * 'op' => 'describe', + * 'src' => <storage path>, + * 'headers' => <HTTP header name/value map> + * ] + * @endcode + * + * g) Do nothing (no-op) + * @code + * [ + * 'op' => 'null', + * ] + * @endcode + * + * Boolean flags for operations (operation-specific): + * - ignoreMissingSource : The operation will simply succeed and do + * nothing if the source file does not exist. + * - overwrite : Any destination file will be overwritten. + * - overwriteSame : If a file already exists at the destination with the + * same contents, then do nothing to the destination file + * instead of giving an error. This does not compare headers. + * This option is ignored if 'overwrite' is already provided. + * - headers : If supplied, the result of merging these headers with any + * existing source file headers (replacing conflicting ones) + * will be set as the destination file headers. Headers are + * deleted if their value is set to the empty string. When a + * file has headers they are included in responses to GET and + * HEAD requests to the backing store for that file. + * Header values should be no larger than 255 bytes, except for + * Content-Disposition. The system might ignore or truncate any + * headers that are too long to store (exact limits will vary). + * Backends that don't support metadata ignore this. (since 1.21) + * + * $opts is an associative of boolean flags, including: + * - force : Operation precondition errors no longer trigger an abort. + * Any remaining operations are still attempted. Unexpected + * failures may still cause remaining operations to be aborted. + * - nonLocking : No locks are acquired for the operations. + * This can increase performance for non-critical writes. + * This has no effect unless the 'force' flag is set. + * - nonJournaled : Don't log this operation batch in the file journal. + * This limits the ability of recovery scripts. + * - parallelize : Try to do operations in parallel when possible. + * - bypassReadOnly : Allow writes in read-only mode. (since 1.20) + * - preserveCache : Don't clear the process cache before checking files. + * This should only be used if all entries in the process + * cache were added after the files were already locked. (since 1.20) + * + * @remarks Remarks on locking: + * File system paths given to operations should refer to files that are + * already locked or otherwise safe from modification from other processes. + * Normally these files will be new temp files, which should be adequate. + * + * @par Return value: + * + * This returns a Status, which contains all warnings and fatals that occurred + * during the operation. The 'failCount', 'successCount', and 'success' members + * will reflect each operation attempted. + * + * The StatusValue will be "OK" unless: + * - a) unexpected operation errors occurred (network partitions, disk full...) + * - b) significant operation errors occurred and 'force' was not set + * + * @param array $ops List of operations to execute in order + * @param array $opts Batch operation options + * @return StatusValue + */ + final public function doOperations( array $ops, array $opts = [] ) { + if ( empty( $opts['bypassReadOnly'] ) && $this->isReadOnly() ) { + return $this->newStatus( 'backend-fail-readonly', $this->name, $this->readOnly ); + } + if ( !count( $ops ) ) { + return $this->newStatus(); // nothing to do + } + + $ops = $this->resolveFSFileObjects( $ops ); + if ( empty( $opts['force'] ) ) { // sanity + unset( $opts['nonLocking'] ); + } + + /** @noinspection PhpUnusedLocalVariableInspection */ + $scope = $this->getScopedPHPBehaviorForOps(); // try to ignore client aborts + + return $this->doOperationsInternal( $ops, $opts ); + } + + /** + * @see FileBackend::doOperations() + * @param array $ops + * @param array $opts + */ + abstract protected function doOperationsInternal( array $ops, array $opts ); + + /** + * Same as doOperations() except it takes a single operation. + * If you are doing a batch of operations that should either + * all succeed or all fail, then use that function instead. + * + * @see FileBackend::doOperations() + * + * @param array $op Operation + * @param array $opts Operation options + * @return StatusValue + */ + final public function doOperation( array $op, array $opts = [] ) { + return $this->doOperations( [ $op ], $opts ); + } + + /** + * Performs a single create operation. + * This sets $params['op'] to 'create' and passes it to doOperation(). + * + * @see FileBackend::doOperation() + * + * @param array $params Operation parameters + * @param array $opts Operation options + * @return StatusValue + */ + final public function create( array $params, array $opts = [] ) { + return $this->doOperation( [ 'op' => 'create' ] + $params, $opts ); + } + + /** + * Performs a single store operation. + * This sets $params['op'] to 'store' and passes it to doOperation(). + * + * @see FileBackend::doOperation() + * + * @param array $params Operation parameters + * @param array $opts Operation options + * @return StatusValue + */ + final public function store( array $params, array $opts = [] ) { + return $this->doOperation( [ 'op' => 'store' ] + $params, $opts ); + } + + /** + * Performs a single copy operation. + * This sets $params['op'] to 'copy' and passes it to doOperation(). + * + * @see FileBackend::doOperation() + * + * @param array $params Operation parameters + * @param array $opts Operation options + * @return StatusValue + */ + final public function copy( array $params, array $opts = [] ) { + return $this->doOperation( [ 'op' => 'copy' ] + $params, $opts ); + } + + /** + * Performs a single move operation. + * This sets $params['op'] to 'move' and passes it to doOperation(). + * + * @see FileBackend::doOperation() + * + * @param array $params Operation parameters + * @param array $opts Operation options + * @return StatusValue + */ + final public function move( array $params, array $opts = [] ) { + return $this->doOperation( [ 'op' => 'move' ] + $params, $opts ); + } + + /** + * Performs a single delete operation. + * This sets $params['op'] to 'delete' and passes it to doOperation(). + * + * @see FileBackend::doOperation() + * + * @param array $params Operation parameters + * @param array $opts Operation options + * @return StatusValue + */ + final public function delete( array $params, array $opts = [] ) { + return $this->doOperation( [ 'op' => 'delete' ] + $params, $opts ); + } + + /** + * Performs a single describe operation. + * This sets $params['op'] to 'describe' and passes it to doOperation(). + * + * @see FileBackend::doOperation() + * + * @param array $params Operation parameters + * @param array $opts Operation options + * @return StatusValue + * @since 1.21 + */ + final public function describe( array $params, array $opts = [] ) { + return $this->doOperation( [ 'op' => 'describe' ] + $params, $opts ); + } + + /** + * Perform a set of independent file operations on some files. + * + * This does no locking, nor journaling, and possibly no stat calls. + * Any destination files that already exist will be overwritten. + * This should *only* be used on non-original files, like cache files. + * + * Supported operations and their parameters: + * - create + * - store + * - copy + * - move + * - delete + * - describe (since 1.21) + * - null + * + * FSFile/TempFSFile object support was added in 1.27. + * + * a) Create a new file in storage with the contents of a string + * @code + * [ + * 'op' => 'create', + * 'dst' => <storage path>, + * 'content' => <string of new file contents>, + * 'headers' => <HTTP header name/value map> # since 1.21 + * ] + * @endcode + * + * b) Copy a file system file into storage + * @code + * [ + * 'op' => 'store', + * 'src' => <file system path, FSFile, or TempFSFile>, + * 'dst' => <storage path>, + * 'headers' => <HTTP header name/value map> # since 1.21 + * ] + * @endcode + * + * c) Copy a file within storage + * @code + * [ + * 'op' => 'copy', + * 'src' => <storage path>, + * 'dst' => <storage path>, + * 'ignoreMissingSource' => <boolean>, # since 1.21 + * 'headers' => <HTTP header name/value map> # since 1.21 + * ] + * @endcode + * + * d) Move a file within storage + * @code + * [ + * 'op' => 'move', + * 'src' => <storage path>, + * 'dst' => <storage path>, + * 'ignoreMissingSource' => <boolean>, # since 1.21 + * 'headers' => <HTTP header name/value map> # since 1.21 + * ] + * @endcode + * + * e) Delete a file within storage + * @code + * [ + * 'op' => 'delete', + * 'src' => <storage path>, + * 'ignoreMissingSource' => <boolean> + * ] + * @endcode + * + * f) Update metadata for a file within storage + * @code + * [ + * 'op' => 'describe', + * 'src' => <storage path>, + * 'headers' => <HTTP header name/value map> + * ] + * @endcode + * + * g) Do nothing (no-op) + * @code + * [ + * 'op' => 'null', + * ] + * @endcode + * + * @par Boolean flags for operations (operation-specific): + * - ignoreMissingSource : The operation will simply succeed and do + * nothing if the source file does not exist. + * - headers : If supplied with a header name/value map, the backend will + * reply with these headers when GETs/HEADs of the destination + * file are made. Header values should be smaller than 256 bytes. + * Content-Disposition headers can be longer, though the system + * might ignore or truncate ones that are too long to store. + * Existing headers will remain, but these will replace any + * conflicting previous headers, and headers will be removed + * if they are set to an empty string. + * Backends that don't support metadata ignore this. (since 1.21) + * + * $opts is an associative of boolean flags, including: + * - bypassReadOnly : Allow writes in read-only mode (since 1.20) + * + * @par Return value: + * This returns a Status, which contains all warnings and fatals that occurred + * during the operation. The 'failCount', 'successCount', and 'success' members + * will reflect each operation attempted for the given files. The StatusValue will be + * considered "OK" as long as no fatal errors occurred. + * + * @param array $ops Set of operations to execute + * @param array $opts Batch operation options + * @return StatusValue + * @since 1.20 + */ + final public function doQuickOperations( array $ops, array $opts = [] ) { + if ( empty( $opts['bypassReadOnly'] ) && $this->isReadOnly() ) { + return $this->newStatus( 'backend-fail-readonly', $this->name, $this->readOnly ); + } + if ( !count( $ops ) ) { + return $this->newStatus(); // nothing to do + } + + $ops = $this->resolveFSFileObjects( $ops ); + foreach ( $ops as &$op ) { + $op['overwrite'] = true; // avoids RTTs in key/value stores + } + + /** @noinspection PhpUnusedLocalVariableInspection */ + $scope = $this->getScopedPHPBehaviorForOps(); // try to ignore client aborts + + return $this->doQuickOperationsInternal( $ops ); + } + + /** + * @see FileBackend::doQuickOperations() + * @param array $ops + * @since 1.20 + */ + abstract protected function doQuickOperationsInternal( array $ops ); + + /** + * Same as doQuickOperations() except it takes a single operation. + * If you are doing a batch of operations, then use that function instead. + * + * @see FileBackend::doQuickOperations() + * + * @param array $op Operation + * @return StatusValue + * @since 1.20 + */ + final public function doQuickOperation( array $op ) { + return $this->doQuickOperations( [ $op ] ); + } + + /** + * Performs a single quick create operation. + * This sets $params['op'] to 'create' and passes it to doQuickOperation(). + * + * @see FileBackend::doQuickOperation() + * + * @param array $params Operation parameters + * @return StatusValue + * @since 1.20 + */ + final public function quickCreate( array $params ) { + return $this->doQuickOperation( [ 'op' => 'create' ] + $params ); + } + + /** + * Performs a single quick store operation. + * This sets $params['op'] to 'store' and passes it to doQuickOperation(). + * + * @see FileBackend::doQuickOperation() + * + * @param array $params Operation parameters + * @return StatusValue + * @since 1.20 + */ + final public function quickStore( array $params ) { + return $this->doQuickOperation( [ 'op' => 'store' ] + $params ); + } + + /** + * Performs a single quick copy operation. + * This sets $params['op'] to 'copy' and passes it to doQuickOperation(). + * + * @see FileBackend::doQuickOperation() + * + * @param array $params Operation parameters + * @return StatusValue + * @since 1.20 + */ + final public function quickCopy( array $params ) { + return $this->doQuickOperation( [ 'op' => 'copy' ] + $params ); + } + + /** + * Performs a single quick move operation. + * This sets $params['op'] to 'move' and passes it to doQuickOperation(). + * + * @see FileBackend::doQuickOperation() + * + * @param array $params Operation parameters + * @return StatusValue + * @since 1.20 + */ + final public function quickMove( array $params ) { + return $this->doQuickOperation( [ 'op' => 'move' ] + $params ); + } + + /** + * Performs a single quick delete operation. + * This sets $params['op'] to 'delete' and passes it to doQuickOperation(). + * + * @see FileBackend::doQuickOperation() + * + * @param array $params Operation parameters + * @return StatusValue + * @since 1.20 + */ + final public function quickDelete( array $params ) { + return $this->doQuickOperation( [ 'op' => 'delete' ] + $params ); + } + + /** + * Performs a single quick describe operation. + * This sets $params['op'] to 'describe' and passes it to doQuickOperation(). + * + * @see FileBackend::doQuickOperation() + * + * @param array $params Operation parameters + * @return StatusValue + * @since 1.21 + */ + final public function quickDescribe( array $params ) { + return $this->doQuickOperation( [ 'op' => 'describe' ] + $params ); + } + + /** + * Concatenate a list of storage files into a single file system file. + * The target path should refer to a file that is already locked or + * otherwise safe from modification from other processes. Normally, + * the file will be a new temp file, which should be adequate. + * + * @param array $params Operation parameters, include: + * - srcs : ordered source storage paths (e.g. chunk1, chunk2, ...) + * - dst : file system path to 0-byte temp file + * - parallelize : try to do operations in parallel when possible + * @return StatusValue + */ + abstract public function concatenate( array $params ); + + /** + * Prepare a storage directory for usage. + * This will create any required containers and parent directories. + * Backends using key/value stores only need to create the container. + * + * The 'noAccess' and 'noListing' parameters works the same as in secure(), + * except they are only applied *if* the directory/container had to be created. + * These flags should always be set for directories that have private files. + * However, setting them is not guaranteed to actually do anything. + * Additional server configuration may be needed to achieve the desired effect. + * + * @param array $params Parameters include: + * - dir : storage directory + * - noAccess : try to deny file access (since 1.20) + * - noListing : try to deny file listing (since 1.20) + * - bypassReadOnly : allow writes in read-only mode (since 1.20) + * @return StatusValue + */ + final public function prepare( array $params ) { + if ( empty( $params['bypassReadOnly'] ) && $this->isReadOnly() ) { + return $this->newStatus( 'backend-fail-readonly', $this->name, $this->readOnly ); + } + /** @noinspection PhpUnusedLocalVariableInspection */ + $scope = $this->getScopedPHPBehaviorForOps(); // try to ignore client aborts + return $this->doPrepare( $params ); + } + + /** + * @see FileBackend::prepare() + * @param array $params + */ + abstract protected function doPrepare( array $params ); + + /** + * Take measures to block web access to a storage directory and + * the container it belongs to. FS backends might add .htaccess + * files whereas key/value store backends might revoke container + * access to the storage user representing end-users in web requests. + * + * This is not guaranteed to actually make files or listings publically hidden. + * Additional server configuration may be needed to achieve the desired effect. + * + * @param array $params Parameters include: + * - dir : storage directory + * - noAccess : try to deny file access + * - noListing : try to deny file listing + * - bypassReadOnly : allow writes in read-only mode (since 1.20) + * @return StatusValue + */ + final public function secure( array $params ) { + if ( empty( $params['bypassReadOnly'] ) && $this->isReadOnly() ) { + return $this->newStatus( 'backend-fail-readonly', $this->name, $this->readOnly ); + } + /** @noinspection PhpUnusedLocalVariableInspection */ + $scope = $this->getScopedPHPBehaviorForOps(); // try to ignore client aborts + return $this->doSecure( $params ); + } + + /** + * @see FileBackend::secure() + * @param array $params + */ + abstract protected function doSecure( array $params ); + + /** + * Remove measures to block web access to a storage directory and + * the container it belongs to. FS backends might remove .htaccess + * files whereas key/value store backends might grant container + * access to the storage user representing end-users in web requests. + * This essentially can undo the result of secure() calls. + * + * This is not guaranteed to actually make files or listings publically viewable. + * Additional server configuration may be needed to achieve the desired effect. + * + * @param array $params Parameters include: + * - dir : storage directory + * - access : try to allow file access + * - listing : try to allow file listing + * - bypassReadOnly : allow writes in read-only mode (since 1.20) + * @return StatusValue + * @since 1.20 + */ + final public function publish( array $params ) { + if ( empty( $params['bypassReadOnly'] ) && $this->isReadOnly() ) { + return $this->newStatus( 'backend-fail-readonly', $this->name, $this->readOnly ); + } + /** @noinspection PhpUnusedLocalVariableInspection */ + $scope = $this->getScopedPHPBehaviorForOps(); // try to ignore client aborts + return $this->doPublish( $params ); + } + + /** + * @see FileBackend::publish() + * @param array $params + */ + abstract protected function doPublish( array $params ); + + /** + * Delete a storage directory if it is empty. + * Backends using key/value stores may do nothing unless the directory + * is that of an empty container, in which case it will be deleted. + * + * @param array $params Parameters include: + * - dir : storage directory + * - recursive : recursively delete empty subdirectories first (since 1.20) + * - bypassReadOnly : allow writes in read-only mode (since 1.20) + * @return StatusValue + */ + final public function clean( array $params ) { + if ( empty( $params['bypassReadOnly'] ) && $this->isReadOnly() ) { + return $this->newStatus( 'backend-fail-readonly', $this->name, $this->readOnly ); + } + /** @noinspection PhpUnusedLocalVariableInspection */ + $scope = $this->getScopedPHPBehaviorForOps(); // try to ignore client aborts + return $this->doClean( $params ); + } + + /** + * @see FileBackend::clean() + * @param array $params + */ + abstract protected function doClean( array $params ); + + /** + * Enter file operation scope. + * This just makes PHP ignore user aborts/disconnects until the return + * value leaves scope. This returns null and does nothing in CLI mode. + * + * @return ScopedCallback|null + */ + final protected function getScopedPHPBehaviorForOps() { + if ( PHP_SAPI != 'cli' ) { // https://bugs.php.net/bug.php?id=47540 + $old = ignore_user_abort( true ); // avoid half-finished operations + return new ScopedCallback( function () use ( $old ) { + ignore_user_abort( $old ); + } ); + } + + return null; + } + + /** + * Check if a file exists at a storage path in the backend. + * This returns false if only a directory exists at the path. + * + * @param array $params Parameters include: + * - src : source storage path + * - latest : use the latest available data + * @return bool|null Returns null on failure + */ + abstract public function fileExists( array $params ); + + /** + * Get the last-modified timestamp of the file at a storage path. + * + * @param array $params Parameters include: + * - src : source storage path + * - latest : use the latest available data + * @return string|bool TS_MW timestamp or false on failure + */ + abstract public function getFileTimestamp( array $params ); + + /** + * Get the contents of a file at a storage path in the backend. + * This should be avoided for potentially large files. + * + * @param array $params Parameters include: + * - src : source storage path + * - latest : use the latest available data + * @return string|bool Returns false on failure + */ + final public function getFileContents( array $params ) { + $contents = $this->getFileContentsMulti( + [ 'srcs' => [ $params['src'] ] ] + $params ); + + return $contents[$params['src']]; + } + + /** + * Like getFileContents() except it takes an array of storage paths + * and returns a map of storage paths to strings (or null on failure). + * The map keys (paths) are in the same order as the provided list of paths. + * + * @see FileBackend::getFileContents() + * + * @param array $params Parameters include: + * - srcs : list of source storage paths + * - latest : use the latest available data + * - parallelize : try to do operations in parallel when possible + * @return array Map of (path name => string or false on failure) + * @since 1.20 + */ + abstract public function getFileContentsMulti( array $params ); + + /** + * Get metadata about a file at a storage path in the backend. + * If the file does not exist, then this returns false. + * Otherwise, the result is an associative array that includes: + * - headers : map of HTTP headers used for GET/HEAD requests (name => value) + * - metadata : map of file metadata (name => value) + * Metadata keys and headers names will be returned in all lower-case. + * Additional values may be included for internal use only. + * + * Use FileBackend::hasFeatures() to check how well this is supported. + * + * @param array $params + * $params include: + * - src : source storage path + * - latest : use the latest available data + * @return array|bool Returns false on failure + * @since 1.23 + */ + abstract public function getFileXAttributes( array $params ); + + /** + * Get the size (bytes) of a file at a storage path in the backend. + * + * @param array $params Parameters include: + * - src : source storage path + * - latest : use the latest available data + * @return int|bool Returns false on failure + */ + abstract public function getFileSize( array $params ); + + /** + * Get quick information about a file at a storage path in the backend. + * If the file does not exist, then this returns false. + * Otherwise, the result is an associative array that includes: + * - mtime : the last-modified timestamp (TS_MW) + * - size : the file size (bytes) + * Additional values may be included for internal use only. + * + * @param array $params Parameters include: + * - src : source storage path + * - latest : use the latest available data + * @return array|bool|null Returns null on failure + */ + abstract public function getFileStat( array $params ); + + /** + * Get a SHA-1 hash of the file at a storage path in the backend. + * + * @param array $params Parameters include: + * - src : source storage path + * - latest : use the latest available data + * @return string|bool Hash string or false on failure + */ + abstract public function getFileSha1Base36( array $params ); + + /** + * Get the properties of the file at a storage path in the backend. + * This gives the result of FSFile::getProps() on a local copy of the file. + * + * @param array $params Parameters include: + * - src : source storage path + * - latest : use the latest available data + * @return array Returns FSFile::placeholderProps() on failure + */ + abstract public function getFileProps( array $params ); + + /** + * Stream the file at a storage path in the backend. + * + * If the file does not exists, an HTTP 404 error will be given. + * Appropriate HTTP headers (Status, Content-Type, Content-Length) + * will be sent if streaming began, while none will be sent otherwise. + * Implementations should flush the output buffer before sending data. + * + * @param array $params Parameters include: + * - src : source storage path + * - headers : list of additional HTTP headers to send if the file exists + * - options : HTTP request header map with lower case keys (since 1.28). Supports: + * range : format is "bytes=(\d*-\d*)" + * if-modified-since : format is an HTTP date + * - headless : only include the body (and headers from "headers") (since 1.28) + * - latest : use the latest available data + * - allowOB : preserve any output buffers (since 1.28) + * @return StatusValue + */ + abstract public function streamFile( array $params ); + + /** + * Returns a file system file, identical to the file at a storage path. + * The file returned is either: + * - a) A local copy of the file at a storage path in the backend. + * The temporary copy will have the same extension as the source. + * - b) An original of the file at a storage path in the backend. + * Temporary files may be purged when the file object falls out of scope. + * + * Write operations should *never* be done on this file as some backends + * may do internal tracking or may be instances of FileBackendMultiWrite. + * In that latter case, there are copies of the file that must stay in sync. + * Additionally, further calls to this function may return the same file. + * + * @param array $params Parameters include: + * - src : source storage path + * - latest : use the latest available data + * @return FSFile|null Returns null on failure + */ + final public function getLocalReference( array $params ) { + $fsFiles = $this->getLocalReferenceMulti( + [ 'srcs' => [ $params['src'] ] ] + $params ); + + return $fsFiles[$params['src']]; + } + + /** + * Like getLocalReference() except it takes an array of storage paths + * and returns a map of storage paths to FSFile objects (or null on failure). + * The map keys (paths) are in the same order as the provided list of paths. + * + * @see FileBackend::getLocalReference() + * + * @param array $params Parameters include: + * - srcs : list of source storage paths + * - latest : use the latest available data + * - parallelize : try to do operations in parallel when possible + * @return array Map of (path name => FSFile or null on failure) + * @since 1.20 + */ + abstract public function getLocalReferenceMulti( array $params ); + + /** + * Get a local copy on disk of the file at a storage path in the backend. + * The temporary copy will have the same file extension as the source. + * Temporary files may be purged when the file object falls out of scope. + * + * @param array $params Parameters include: + * - src : source storage path + * - latest : use the latest available data + * @return TempFSFile|null Returns null on failure + */ + final public function getLocalCopy( array $params ) { + $tmpFiles = $this->getLocalCopyMulti( + [ 'srcs' => [ $params['src'] ] ] + $params ); + + return $tmpFiles[$params['src']]; + } + + /** + * Like getLocalCopy() except it takes an array of storage paths and + * returns a map of storage paths to TempFSFile objects (or null on failure). + * The map keys (paths) are in the same order as the provided list of paths. + * + * @see FileBackend::getLocalCopy() + * + * @param array $params Parameters include: + * - srcs : list of source storage paths + * - latest : use the latest available data + * - parallelize : try to do operations in parallel when possible + * @return array Map of (path name => TempFSFile or null on failure) + * @since 1.20 + */ + abstract public function getLocalCopyMulti( array $params ); + + /** + * Return an HTTP URL to a given file that requires no authentication to use. + * The URL may be pre-authenticated (via some token in the URL) and temporary. + * This will return null if the backend cannot make an HTTP URL for the file. + * + * This is useful for key/value stores when using scripts that seek around + * large files and those scripts (and the backend) support HTTP Range headers. + * Otherwise, one would need to use getLocalReference(), which involves loading + * the entire file on to local disk. + * + * @param array $params Parameters include: + * - src : source storage path + * - ttl : lifetime (seconds) if pre-authenticated; default is 1 day + * @return string|null + * @since 1.21 + */ + abstract public function getFileHttpUrl( array $params ); + + /** + * Check if a directory exists at a given storage path. + * Backends using key/value stores will check if the path is a + * virtual directory, meaning there are files under the given directory. + * + * Storage backends with eventual consistency might return stale data. + * + * @param array $params Parameters include: + * - dir : storage directory + * @return bool|null Returns null on failure + * @since 1.20 + */ + abstract public function directoryExists( array $params ); + + /** + * Get an iterator to list *all* directories under a storage directory. + * If the directory is of the form "mwstore://backend/container", + * then all directories in the container will be listed. + * If the directory is of form "mwstore://backend/container/dir", + * then all directories directly under that directory will be listed. + * Results will be storage directories relative to the given directory. + * + * Storage backends with eventual consistency might return stale data. + * + * Failures during iteration can result in FileBackendError exceptions (since 1.22). + * + * @param array $params Parameters include: + * - dir : storage directory + * - topOnly : only return direct child dirs of the directory + * @return Traversable|array|null Returns null on failure + * @since 1.20 + */ + abstract public function getDirectoryList( array $params ); + + /** + * Same as FileBackend::getDirectoryList() except only lists + * directories that are immediately under the given directory. + * + * Storage backends with eventual consistency might return stale data. + * + * Failures during iteration can result in FileBackendError exceptions (since 1.22). + * + * @param array $params Parameters include: + * - dir : storage directory + * @return Traversable|array|null Returns null on failure + * @since 1.20 + */ + final public function getTopDirectoryList( array $params ) { + return $this->getDirectoryList( [ 'topOnly' => true ] + $params ); + } + + /** + * Get an iterator to list *all* stored files under a storage directory. + * If the directory is of the form "mwstore://backend/container", + * then all files in the container will be listed. + * If the directory is of form "mwstore://backend/container/dir", + * then all files under that directory will be listed. + * Results will be storage paths relative to the given directory. + * + * Storage backends with eventual consistency might return stale data. + * + * Failures during iteration can result in FileBackendError exceptions (since 1.22). + * + * @param array $params Parameters include: + * - dir : storage directory + * - topOnly : only return direct child files of the directory (since 1.20) + * - adviseStat : set to true if stat requests will be made on the files (since 1.22) + * @return Traversable|array|null Returns null on failure + */ + abstract public function getFileList( array $params ); + + /** + * Same as FileBackend::getFileList() except only lists + * files that are immediately under the given directory. + * + * Storage backends with eventual consistency might return stale data. + * + * Failures during iteration can result in FileBackendError exceptions (since 1.22). + * + * @param array $params Parameters include: + * - dir : storage directory + * - adviseStat : set to true if stat requests will be made on the files (since 1.22) + * @return Traversable|array|null Returns null on failure + * @since 1.20 + */ + final public function getTopFileList( array $params ) { + return $this->getFileList( [ 'topOnly' => true ] + $params ); + } + + /** + * Preload persistent file stat cache and property cache into in-process cache. + * This should be used when stat calls will be made on a known list of a many files. + * + * @see FileBackend::getFileStat() + * + * @param array $paths Storage paths + */ + abstract public function preloadCache( array $paths ); + + /** + * Invalidate any in-process file stat and property cache. + * If $paths is given, then only the cache for those files will be cleared. + * + * @see FileBackend::getFileStat() + * + * @param array $paths Storage paths (optional) + */ + abstract public function clearCache( array $paths = null ); + + /** + * Preload file stat information (concurrently if possible) into in-process cache. + * + * This should be used when stat calls will be made on a known list of a many files. + * This does not make use of the persistent file stat cache. + * + * @see FileBackend::getFileStat() + * + * @param array $params Parameters include: + * - srcs : list of source storage paths + * - latest : use the latest available data + * @return bool All requests proceeded without I/O errors (since 1.24) + * @since 1.23 + */ + abstract public function preloadFileStat( array $params ); + + /** + * Lock the files at the given storage paths in the backend. + * This will either lock all the files or none (on failure). + * + * Callers should consider using getScopedFileLocks() instead. + * + * @param array $paths Storage paths + * @param int $type LockManager::LOCK_* constant + * @param int $timeout Timeout in seconds (0 means non-blocking) (since 1.24) + * @return StatusValue + */ + final public function lockFiles( array $paths, $type, $timeout = 0 ) { + $paths = array_map( 'FileBackend::normalizeStoragePath', $paths ); + + return $this->wrapStatus( $this->lockManager->lock( $paths, $type, $timeout ) ); + } + + /** + * Unlock the files at the given storage paths in the backend. + * + * @param array $paths Storage paths + * @param int $type LockManager::LOCK_* constant + * @return StatusValue + */ + final public function unlockFiles( array $paths, $type ) { + $paths = array_map( 'FileBackend::normalizeStoragePath', $paths ); + + return $this->wrapStatus( $this->lockManager->unlock( $paths, $type ) ); + } + + /** + * Lock the files at the given storage paths in the backend. + * This will either lock all the files or none (on failure). + * On failure, the StatusValue object will be updated with errors. + * + * Once the return value goes out scope, the locks will be released and + * the StatusValue updated. Unlock fatals will not change the StatusValue "OK" value. + * + * @see ScopedLock::factory() + * + * @param array $paths List of storage paths or map of lock types to path lists + * @param int|string $type LockManager::LOCK_* constant or "mixed" + * @param StatusValue $status StatusValue to update on lock/unlock + * @param int $timeout Timeout in seconds (0 means non-blocking) (since 1.24) + * @return ScopedLock|null Returns null on failure + */ + final public function getScopedFileLocks( + array $paths, $type, StatusValue $status, $timeout = 0 + ) { + if ( $type === 'mixed' ) { + foreach ( $paths as &$typePaths ) { + $typePaths = array_map( 'FileBackend::normalizeStoragePath', $typePaths ); + } + } else { + $paths = array_map( 'FileBackend::normalizeStoragePath', $paths ); + } + + return ScopedLock::factory( $this->lockManager, $paths, $type, $status, $timeout ); + } + + /** + * Get an array of scoped locks needed for a batch of file operations. + * + * Normally, FileBackend::doOperations() handles locking, unless + * the 'nonLocking' param is passed in. This function is useful if you + * want the files to be locked for a broader scope than just when the + * files are changing. For example, if you need to update DB metadata, + * you may want to keep the files locked until finished. + * + * @see FileBackend::doOperations() + * + * @param array $ops List of file operations to FileBackend::doOperations() + * @param StatusValue $status StatusValue to update on lock/unlock + * @return ScopedLock|null + * @since 1.20 + */ + abstract public function getScopedLocksForOps( array $ops, StatusValue $status ); + + /** + * Get the root storage path of this backend. + * All container paths are "subdirectories" of this path. + * + * @return string Storage path + * @since 1.20 + */ + final public function getRootStoragePath() { + return "mwstore://{$this->name}"; + } + + /** + * Get the storage path for the given container for this backend + * + * @param string $container Container name + * @return string Storage path + * @since 1.21 + */ + final public function getContainerStoragePath( $container ) { + return $this->getRootStoragePath() . "/{$container}"; + } + + /** + * Get the file journal object for this backend + * + * @return FileJournal + */ + final public function getJournal() { + return $this->fileJournal; + } + + /** + * Convert FSFile 'src' paths to string paths (with an 'srcRef' field set to the FSFile) + * + * The 'srcRef' field keeps any TempFSFile objects in scope for the backend to have it + * around as long it needs (which may vary greatly depending on configuration) + * + * @param array $ops File operation batch for FileBaclend::doOperations() + * @return array File operation batch + */ + protected function resolveFSFileObjects( array $ops ) { + foreach ( $ops as &$op ) { + $src = isset( $op['src'] ) ? $op['src'] : null; + if ( $src instanceof FSFile ) { + $op['srcRef'] = $src; + $op['src'] = $src->getPath(); + } + } + unset( $op ); + + return $ops; + } + + /** + * Check if a given path is a "mwstore://" path. + * This does not do any further validation or any existence checks. + * + * @param string $path + * @return bool + */ + final public static function isStoragePath( $path ) { + return ( strpos( $path, 'mwstore://' ) === 0 ); + } + + /** + * Split a storage path into a backend name, a container name, + * and a relative file path. The relative path may be the empty string. + * This does not do any path normalization or traversal checks. + * + * @param string $storagePath + * @return array (backend, container, rel object) or (null, null, null) + */ + final public static function splitStoragePath( $storagePath ) { + if ( self::isStoragePath( $storagePath ) ) { + // Remove the "mwstore://" prefix and split the path + $parts = explode( '/', substr( $storagePath, 10 ), 3 ); + if ( count( $parts ) >= 2 && $parts[0] != '' && $parts[1] != '' ) { + if ( count( $parts ) == 3 ) { + return $parts; // e.g. "backend/container/path" + } else { + return [ $parts[0], $parts[1], '' ]; // e.g. "backend/container" + } + } + } + + return [ null, null, null ]; + } + + /** + * Normalize a storage path by cleaning up directory separators. + * Returns null if the path is not of the format of a valid storage path. + * + * @param string $storagePath + * @return string|null + */ + final public static function normalizeStoragePath( $storagePath ) { + list( $backend, $container, $relPath ) = self::splitStoragePath( $storagePath ); + if ( $relPath !== null ) { // must be for this backend + $relPath = self::normalizeContainerPath( $relPath ); + if ( $relPath !== null ) { + return ( $relPath != '' ) + ? "mwstore://{$backend}/{$container}/{$relPath}" + : "mwstore://{$backend}/{$container}"; + } + } + + return null; + } + + /** + * Get the parent storage directory of a storage path. + * This returns a path like "mwstore://backend/container", + * "mwstore://backend/container/...", or null if there is no parent. + * + * @param string $storagePath + * @return string|null + */ + final public static function parentStoragePath( $storagePath ) { + $storagePath = dirname( $storagePath ); + list( , , $rel ) = self::splitStoragePath( $storagePath ); + + return ( $rel === null ) ? null : $storagePath; + } + + /** + * Get the final extension from a storage or FS path + * + * @param string $path + * @param string $case One of (rawcase, uppercase, lowercase) (since 1.24) + * @return string + */ + final public static function extensionFromPath( $path, $case = 'lowercase' ) { + $i = strrpos( $path, '.' ); + $ext = $i ? substr( $path, $i + 1 ) : ''; + + if ( $case === 'lowercase' ) { + $ext = strtolower( $ext ); + } elseif ( $case === 'uppercase' ) { + $ext = strtoupper( $ext ); + } + + return $ext; + } + + /** + * Check if a relative path has no directory traversals + * + * @param string $path + * @return bool + * @since 1.20 + */ + final public static function isPathTraversalFree( $path ) { + return ( self::normalizeContainerPath( $path ) !== null ); + } + + /** + * Build a Content-Disposition header value per RFC 6266. + * + * @param string $type One of (attachment, inline) + * @param string $filename Suggested file name (should not contain slashes) + * @throws FileBackendError + * @return string + * @since 1.20 + */ + final public static function makeContentDisposition( $type, $filename = '' ) { + $parts = []; + + $type = strtolower( $type ); + if ( !in_array( $type, [ 'inline', 'attachment' ] ) ) { + throw new InvalidArgumentException( "Invalid Content-Disposition type '$type'." ); + } + $parts[] = $type; + + if ( strlen( $filename ) ) { + $parts[] = "filename*=UTF-8''" . rawurlencode( basename( $filename ) ); + } + + return implode( ';', $parts ); + } + + /** + * Validate and normalize a relative storage path. + * Null is returned if the path involves directory traversal. + * Traversal is insecure for FS backends and broken for others. + * + * This uses the same traversal protection as Title::secureAndSplit(). + * + * @param string $path Storage path relative to a container + * @return string|null + */ + final protected static function normalizeContainerPath( $path ) { + // Normalize directory separators + $path = strtr( $path, '\\', '/' ); + // Collapse any consecutive directory separators + $path = preg_replace( '![/]{2,}!', '/', $path ); + // Remove any leading directory separator + $path = ltrim( $path, '/' ); + // Use the same traversal protection as Title::secureAndSplit() + if ( strpos( $path, '.' ) !== false ) { + if ( + $path === '.' || + $path === '..' || + strpos( $path, './' ) === 0 || + strpos( $path, '../' ) === 0 || + strpos( $path, '/./' ) !== false || + strpos( $path, '/../' ) !== false + ) { + return null; + } + } + + return $path; + } + + /** + * Yields the result of the status wrapper callback on either: + * - StatusValue::newGood() if this method is called without parameters + * - StatusValue::newFatal() with all parameters to this method if passed in + * + * @param string $args,... + * @return StatusValue + */ + final protected function newStatus() { + $args = func_get_args(); + if ( count( $args ) ) { + $sv = call_user_func_array( [ StatusValue::class, 'newFatal' ], $args ); + } else { + $sv = StatusValue::newGood(); + } + + return $this->wrapStatus( $sv ); + } + + /** + * @param StatusValue $sv + * @return StatusValue Modified status or StatusValue subclass + */ + final protected function wrapStatus( StatusValue $sv ) { + return $this->statusWrapper ? call_user_func( $this->statusWrapper, $sv ) : $sv; + } + + /** + * @param string $section + * @return ScopedCallback|null + */ + protected function scopedProfileSection( $section ) { + if ( $this->profiler ) { + call_user_func( [ $this->profiler, 'profileIn' ], $section ); + return new ScopedCallback( [ $this->profiler, 'profileOut' ], [ $section ] ); + } + + return null; + } + + protected function resetOutputBuffer() { + while ( ob_get_status() ) { + if ( !ob_end_clean() ) { + // Could not remove output buffer handler; abort now + // to avoid getting in some kind of infinite loop. + break; + } + } + } +} |