[BlobAsync] Asynchronous Blob Construction Final Patch

content/browser/fileapi/blob_storage_host.h

-// Copyright 2014 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_FILEAPI_BLOB_STORAGE_HOST_H_
-#define CONTENT_BROWSER_FILEAPI_BLOB_STORAGE_HOST_H_
-
-#include <map>
-#include <set>
-#include <string>
-
-#include "base/compiler_specific.h"
-#include "base/macros.h"
-#include "base/memory/weak_ptr.h"
-#include "content/common/content_export.h"
-#include "storage/common/data_element.h"
-
-class GURL;
-
-namespace storage {
-class BlobDataHandle;
-class BlobStorageHost;
-class BlobStorageContext;
-}
-
-namespace content {
-
-// This class handles the logistics of blob storage for a single child process.
-// There is one instance per child process. When the child process
-// terminates all blob references attibutable to that process go away upon
-// destruction of the instance. The class is single threaded and should
-// only be used on the IO thread.
-class CONTENT_EXPORT BlobStorageHost {
- public:
-  explicit BlobStorageHost(storage::BlobStorageContext* context);
-  ~BlobStorageHost();
-
-  // Methods to support the IPC message protocol.
-  // A false return indicates a problem with the inputs
-  // like a non-existent or pre-existent uuid or url.
-  bool StartBuildingBlob(const std::string& uuid) WARN_UNUSED_RESULT;
-  bool AppendBlobDataItem(const std::string& uuid,
-                          const storage::DataElement& data_item)
-      WARN_UNUSED_RESULT;
-  bool CancelBuildingBlob(const std::string& uuid) WARN_UNUSED_RESULT;
-  bool FinishBuildingBlob(const std::string& uuid,
-                          const std::string& type) WARN_UNUSED_RESULT;
-  bool IncrementBlobRefCount(const std::string& uuid) WARN_UNUSED_RESULT;
-  bool DecrementBlobRefCount(const std::string& uuid) WARN_UNUSED_RESULT;
-  bool RegisterPublicBlobURL(const GURL& blob_url,
-                             const std::string& uuid) WARN_UNUSED_RESULT;
-  bool RevokePublicBlobURL(const GURL& blob_url) WARN_UNUSED_RESULT;
-
- private:
-  typedef std::map<std::string, int> BlobReferenceMap;
-
-  bool IsInUseInHost(const std::string& uuid);
-  bool IsBeingBuiltInHost(const std::string& uuid);
-  bool IsUrlRegisteredInHost(const GURL& blob_url);
-
-  // Collection of blob ids and a count of how many usages
-  // of that id are attributable to this consumer.
-  BlobReferenceMap blobs_inuse_map_;
-
-  // The set of public blob urls coined by this consumer.
-  std::set<GURL> public_blob_urls_;
-
-  base::WeakPtr<storage::BlobStorageContext> context_;
-
-  DISALLOW_COPY_AND_ASSIGN(BlobStorageHost);
-};
-
-}  // namespace content
-
-#endif  // CONTENT_BROWSER_FILEAPI_BLOB_STORAGE_HOST_H_