Blob support for IDB [Chromium]

content/browser/indexed_db/indexed_db_backing_store.h

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_BACKING_STORE_H_
 #define CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_BACKING_STORE_H_
 
 #include <set>
 #include <string>
 #include <vector>
@@ skipping 185 matching lines @@
       RecordIdentifier* record) WARN_UNUSED_RESULT;
   virtual leveldb::Status ClearObjectStore(
       IndexedDBBackingStore::Transaction* transaction,
       int64 database_id,
       int64 object_store_id) WARN_UNUSED_RESULT;
   virtual leveldb::Status DeleteRecord(
       IndexedDBBackingStore::Transaction* transaction,
       int64 database_id,
       int64 object_store_id,
       const RecordIdentifier& record) WARN_UNUSED_RESULT;
+  virtual leveldb::Status DeleteRange(
+      IndexedDBBackingStore::Transaction* transaction,
+      int64 database_id,
+      int64 object_store_id,
+      const IndexedDBKeyRange&) WARN_UNUSED_RESULT;
   virtual leveldb::Status GetKeyGeneratorCurrentNumber(
       IndexedDBBackingStore::Transaction* transaction,
       int64 database_id,
       int64 object_store_id,
       int64* current_number) WARN_UNUSED_RESULT;
   virtual leveldb::Status MaybeUpdateKeyGeneratorCurrentNumber(
       IndexedDBBackingStore::Transaction* transaction,
       int64 database_id,
       int64 object_store_id,
       int64 new_state,
@@ skipping 166 matching lines @@
     ScopedVector<webkit_blob::BlobDataHandle> handles_;
     DISALLOW_COPY_AND_ASSIGN(BlobChangeRecord);
   };
   typedef std::map<std::string, BlobChangeRecord*> BlobChangeMap;
 
   class Transaction {
    public:
     explicit Transaction(IndexedDBBackingStore* backing_store);
     virtual ~Transaction();
     virtual void Begin();
-    virtual leveldb::Status Commit();
+    // The callback will be called eventually on success or failure, or
+    // immediately if phase one is complete due to lack of any blobs to write.
+    virtual leveldb::Status CommitPhaseOne(scoped_refptr<BlobWriteCallback>);
+    virtual leveldb::Status CommitPhaseTwo();
     virtual void Rollback();
     void Reset() {
       backing_store_ = NULL;
       transaction_ = NULL;
     }
     void PutBlobInfo(int64 database_id,
                      int64 object_store_id,
                      const std::string& object_store_data_key,
                      std::vector<IndexedDBBlobInfo>*,
                      ScopedVector<webkit_blob::BlobDataHandle>* handles);
@@ skipping 48 matching lines @@
       virtual ~ChainedBlobWriter() {}
       friend class base::RefCounted<ChainedBlobWriter>;
     };
     class ChainedBlobWriterImpl;
 
     typedef std::vector<WriteDescriptor> WriteDescriptorVec;
 
    private:
     class BlobWriteCallbackWrapper;
 
+    // These return true on success, false on failure.

[cmumford, 2014/05/28 20:34:54]

Nit: You say "these", but the first one (HandleBlobPreTransaction) returns
leveldb::Status. I think you just need to move the comment down one function?

[ericu, 2014/05/28 22:50:42]

Yup; the first one used to return bool before I changed it to leveldb::Status. 
Fixed.

+    leveldb::Status HandleBlobPreTransaction(
+        BlobEntryKeyValuePairVec* new_blob_entries,
+        WriteDescriptorVec* new_files_to_write);
+    bool CollectBlobFilesToRemove();
     // The callback will be called eventually on success or failure.
     void WriteNewBlobs(BlobEntryKeyValuePairVec& new_blob_entries,
                        WriteDescriptorVec& new_files_to_write,
                        scoped_refptr<BlobWriteCallback> callback);
+    leveldb::Status SortBlobsToRemove();
 
     IndexedDBBackingStore* backing_store_;
     scoped_refptr<LevelDBTransaction> transaction_;
     BlobChangeMap blob_change_map_;
     BlobChangeMap incognito_blob_map_;
     int64 database_id_;
+    BlobJournalType blobs_to_remove_;
     scoped_refptr<ChainedBlobWriter> chained_blob_writer_;
   };
 
  protected:
   IndexedDBBackingStore(IndexedDBFactory* indexed_db_factory,
                         const GURL& origin_url,
                         const base::FilePath& blob_path,
                         net::URLRequestContext* request_context,
                         scoped_ptr<LevelDBDatabase> db,
                         scoped_ptr<LevelDBComparator> comparator,
@@ skipping 64 matching lines @@
   scoped_ptr<LevelDBComparator> comparator_;
   // Whenever blobs are registered in active_blob_registry_, indexed_db_factory_
   // will hold a reference to this backing store.
   IndexedDBActiveBlobRegistry active_blob_registry_;
   base::OneShotTimer<IndexedDBBackingStore> close_timer_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_BACKING_STORE_H_