From 7ccbeab5f095ba377e921e3549f3de9b112665fb Mon Sep 17 00:00:00 2001
From: Aaron Schulz <aaron@users.mediawiki.org>
Date: Mon, 30 Jan 2012 08:00:19 +0000
Subject: [PATCH] * r108353: Made FileBackendMultiWrite consistency checks
 configurable. * Removed redundant code from r110259 and added a comment to
 isValidContainerName().

---
 includes/filerepo/backend/FSFileBackend.php   | 10 -------
 includes/filerepo/backend/FileBackend.php     |  1 +
 .../backend/FileBackendMultiWrite.php         | 27 ++++++++++++++++---
 3 files changed, 25 insertions(+), 13 deletions(-)

diff --git a/includes/filerepo/backend/FSFileBackend.php b/includes/filerepo/backend/FSFileBackend.php
index f6748c81b0..3eabd29cfe 100644
--- a/includes/filerepo/backend/FSFileBackend.php
+++ b/includes/filerepo/backend/FSFileBackend.php
@@ -57,16 +57,6 @@ class FSFileBackend extends FileBackendStore {
 			: 0644;
 	}
 
-	/**
-	 * @see FileBackendStore::resolveContainerName()
-	 */
-	protected function resolveContainerName( $container ) {
-		if ( $container !== '.' ) {
-			return $container; // container is not a traversal
-		}
-		return null;
-	}
-
 	/**
 	 * @see FileBackendStore::resolveContainerPath()
 	 */
diff --git a/includes/filerepo/backend/FileBackend.php b/includes/filerepo/backend/FileBackend.php
index fbae494159..53106941bc 100644
--- a/includes/filerepo/backend/FileBackend.php
+++ b/includes/filerepo/backend/FileBackend.php
@@ -1422,6 +1422,7 @@ abstract class FileBackendStore extends FileBackend {
 	final protected static function isValidContainerName( $container ) {
 		// This accounts for Swift and S3 restrictions while leaving room 
 		// for things like '.xxx' (hex shard chars) or '.seg' (segments).
+		// This disallows directory separators or traversal characters.
 		// Note that matching strings URL encode to the same string;
 		// in Swift, the length restriction is *after* URL encoding.
 		return preg_match( '/^[a-z0-9][a-z0-9-_]{0,199}$/i', $container );
diff --git a/includes/filerepo/backend/FileBackendMultiWrite.php b/includes/filerepo/backend/FileBackendMultiWrite.php
index d09462ab71..550a8af367 100644
--- a/includes/filerepo/backend/FileBackendMultiWrite.php
+++ b/includes/filerepo/backend/FileBackendMultiWrite.php
@@ -24,6 +24,11 @@ class FileBackendMultiWrite extends FileBackend {
 	/** @var Array Prioritized list of FileBackendStore objects */
 	protected $backends = array(); // array of (backend index => backends)
 	protected $masterIndex = -1; // integer; index of master backend
+	protected $syncChecks = 0; // integer bitfield
+
+	/* Possible internal backend consistency checks */
+	const CHECK_SIZE = 1;
+	const CHECK_TIME = 2;
 
 	/**
 	 * Construct a proxy backend that consists of several internal backends.
@@ -33,6 +38,9 @@ class FileBackendMultiWrite extends FileBackend {
 	 *                     FileBackendStore class, but with these additional settings:
 	 *                         'class'         : The name of the backend class
 	 *                         'isMultiMaster' : This must be set for one backend.
+	 *     'syncChecks'  : Integer bitfield of internal backend sync checks to perform.
+	 *                     Possible bits include self::CHECK_SIZE and self::CHECK_TIME.
+	 *                     The checks are done before allowing any file operations.
 	 * @param $config Array
 	 */
 	public function __construct( array $config ) {
@@ -61,6 +69,9 @@ class FileBackendMultiWrite extends FileBackend {
 		if ( $this->masterIndex < 0 ) { // need backends and must have a master
 			throw new MWException( 'No master backend defined.' );
 		}
+		$this->syncChecks = isset( $config['syncChecks'] )
+			? $config['syncChecks']
+			: self::CHECK_SIZE;
 	}
 
 	/**
@@ -156,6 +167,9 @@ class FileBackendMultiWrite extends FileBackend {
 	 */
 	public function consistencyCheck( array $paths ) {
 		$status = Status::newGood();
+		if ( $this->syncChecks == 0 ) {
+			return $status; // skip checks
+		}
 
 		$mBackend = $this->backends[$this->masterIndex];
 		foreach ( array_unique( $paths ) as $path ) {
@@ -171,13 +185,20 @@ class FileBackendMultiWrite extends FileBackend {
 				if ( $mStat ) { // file is in master
 					if ( !$cStat ) { // file should exist
 						$status->fatal( 'backend-fail-synced', $path );
-					} elseif ( $cStat['size'] != $mStat['size'] ) { // wrong size
-						$status->fatal( 'backend-fail-synced', $path );
-					} else {
+						continue;
+					}
+					if ( $this->syncChecks & self::CHECK_SIZE ) {
+						if ( $cStat['size'] != $mStat['size'] ) { // wrong size
+							$status->fatal( 'backend-fail-synced', $path );
+							continue;
+						}
+					}
+					if ( $this->syncChecks & self::CHECK_TIME ) {
 						$mTs = wfTimestamp( TS_UNIX, $mStat['mtime'] );
 						$cTs = wfTimestamp( TS_UNIX, $cStat['mtime'] );
 						if ( abs( $mTs - $cTs ) > 30 ) { // outdated file somewhere
 							$status->fatal( 'backend-fail-synced', $path );
+							continue;
 						}
 					}
 				} else { // file is not in master
-- 
2.20.1