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 "storage/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 storage::ShareableFileReference::FinalReleaseCallback GetFinalReleaseCallback( 35 int64 database_id, 36 int64 blob_key); 37 // This closure holds a raw pointer to the IndexedDBActiveBlobRegistry, 38 // and may not be called after it is deleted. 39 base::Closure GetAddBlobRefCallback(int64 database_id, int64 blob_key); 40 // Call this to force the registry to drop its use counts, permitting the 41 // factory to drop any blob-related refcount for the backing store. 42 // This will also turn any outstanding callbacks into no-ops. 43 void ForceShutdown(); 44 45 private: 46 // Maps blob_key -> IsDeleted; if the record's absent, it's not in active use 47 // and we don't care if it's deleted. 48 typedef std::map<int64, bool> SingleDBMap; 49 // Maps DB ID -> SingleDBMap 50 typedef std::map<int64, SingleDBMap> AllDBsMap; 51 typedef std::set<int64> DeletedDBSet; 52 53 void AddBlobRef(int64 database_id, int64 blob_key); 54 void ReleaseBlobRef(int64 database_id, int64 blob_key); 55 static void ReleaseBlobRefThreadSafe( 56 scoped_refptr<base::TaskRunner> task_runner, 57 base::WeakPtr<IndexedDBActiveBlobRegistry> weak_ptr, 58 int64 database_id, 59 int64 blob_key, 60 const base::FilePath& unused); 61 62 AllDBsMap use_tracker_; 63 DeletedDBSet deleted_dbs_; 64 // As long as we've got blobs registered in use_tracker_, 65 // backing_store_->factory() will keep backing_store_ alive for us. And 66 // backing_store_ owns us, so we'll stay alive as long as we're needed. 67 IndexedDBBackingStore* backing_store_; 68 base::WeakPtrFactory<IndexedDBActiveBlobRegistry> weak_factory_; 69 70 DISALLOW_COPY_AND_ASSIGN(IndexedDBActiveBlobRegistry); 71 }; 72 73 } // namespace content 74 75 #endif // CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_ACTIVE_BLOB_REGISTRY_H_ 76