1 // Copyright 2014 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_ACTIVE_BLOB_REGISTRY_H_ 6 #define CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_ACTIVE_BLOB_REGISTRY_H_ 7 8 #include <map> 9 #include <set> 10 #include <utility> 11 #include "base/basictypes.h" 12 #include "base/files/file_path.h" 13 #include "base/memory/weak_ptr.h" 14 #include "content/common/content_export.h" 15 #include "webkit/common/blob/shareable_file_reference.h" 16 17 namespace content { 18 19 class IndexedDBBackingStore; 20 21 class CONTENT_EXPORT IndexedDBActiveBlobRegistry { 22 public: 23 explicit IndexedDBActiveBlobRegistry(IndexedDBBackingStore* backing_store); 24 ~IndexedDBActiveBlobRegistry(); 25 26 // Most methods of this class, and the closure returned by 27 // GetAddBlobRefCallback, should only be called on the backing_store's task 28 // runner. The exception is the closure returned by GetFinalReleaseCallback, 29 // which just calls ReleaseBlobRefThreadSafe. 30 31 // Use DatabaseMetaDataKey::AllBlobsKey for "the whole database". 32 bool MarkDeletedCheckIfUsed(int64 database_id, int64 blob_key); 33 34 webkit_blob::ShareableFileReference::FinalReleaseCallback 35 GetFinalReleaseCallback(int64 database_id, int64 blob_key); 36 // This closure holds a raw pointer to the IndexedDBActiveBlobRegistry, 37 // and may not be called after it is deleted. 38 base::Closure GetAddBlobRefCallback(int64 database_id, int64 blob_key); 39 // Call this to force the registry to drop its use counts, permitting the 40 // factory to drop any blob-related refcount for the backing store. 41 // This will also turn any outstanding callbacks into no-ops. 42 void ForceShutdown(); 43 44 private: 45 void AddBlobRef(int64 database_id, int64 blob_key); 46 void ReleaseBlobRef(int64 database_id, int64 blob_key); 47 static void ReleaseBlobRefThreadSafe( 48 scoped_refptr<base::TaskRunner> task_runner, 49 base::WeakPtr<IndexedDBActiveBlobRegistry> weak_ptr, 50 int64 database_id, 51 int64 blob_key, 52 const base::FilePath& unused); 53 54 // Maps blob_key -> IsDeleted; if the record's absent, it's not in active use 55 // and we don't care if it's deleted. 56 typedef std::map<int64, bool> SingleDBMap; 57 // Maps DB ID -> SingleDBMap 58 typedef std::map<int64, SingleDBMap> AllDBsMap; 59 typedef std::set<int64> DeletedDBSet; 60 61 AllDBsMap use_tracker_; 62 DeletedDBSet deleted_dbs_; 63 // As long as we've got blobs registered in use_tracker_, 64 // backing_store_->factory() will keep backing_store_ alive for us. And 65 // backing_store_ owns us, so we'll stay alive as long as we're needed. 66 IndexedDBBackingStore* backing_store_; 67 base::WeakPtrFactory<IndexedDBActiveBlobRegistry> weak_factory_; 68 69 DISALLOW_COPY_AND_ASSIGN(IndexedDBActiveBlobRegistry); 70 }; 71 72 } // namespace content 73 74 #endif // CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_ACTIVE_BLOB_REGISTRY_H_ 75