[BlobAsync] Patch 3: Renderer Classes & Logic

content/child/blob_storage/blob_transport_controller.h

+// Copyright 2015 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_CHILD_BLOB_STORAGE_BLOB_TRANSPORT_CONTROLLER_H_
+#define CONTENT_CHILD_BLOB_STORAGE_BLOB_TRANSPORT_CONTROLLER_H_
+
+#include <string>
+#include <vector>
+
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/shared_memory_handle.h"
+#include "content/child/blob_storage/blob_transport_temporary_holder.h"
+#include "storage/common/blob_storage/blob_storage_constants.h"
+
+namespace base {
+template <typename T>
+struct DefaultLazyInstanceTraits;
+}
+
+namespace IPC {
+class Sender;
+}
+
+namespace content {
+
+// This class is used to manage all the asynchronous transporation of blobs from
+// the Renderer to the Browser process, where it's handling the Renderer side.
+// This function of this class is to:
+// * Be a lazy singleton,
+// * delegate calls to the BlobTransportTemporaryHolder, and
+// * send IPC responses.
+// Must be used on the IO thread.
+class BlobTransportController {
+ public:
+  static BlobTransportController* GetInstance();
+
+  // This kicks off a blob transfer to the browser thread, which involves
+  // sending an IPC message and storing the blob consolidation object.
+  void InitiateBlobTransfer(const std::string& uuid,
+                            const std::string& type,
+                            scoped_ptr<BlobConsolidation> consolidation,
+                            IPC::Sender* sender);
+
+  // This responds to the request using the sender.
+  void OnMemoryRequest(
+      const std::string& uuid,
+      const std::vector<storage::BlobItemBytesRequest>& requests,
+      std::vector<base::SharedMemoryHandle>* memory_handles,
+      const std::vector<IPC::PlatformFileForTransit>& file_handles,
+      IPC::Sender* sender);
+
+  void OnCancel(const std::string& uuid,
+                storage::IPCBlobCreationCancelCode code);
+
+  void OnDone(const std::string& uuid);
+
+  ~BlobTransportController();
+
+ private:
+  friend struct base::DefaultLazyInstanceTraits<BlobTransportController>;
+
+  BlobTransportController();
+
+  // Sends the IPC to cancel the blob transfer, and releases the blob from
+  // internal storage.
+  void CancelBlobTransfer(const std::string& uuid,
+                          storage::IPCBlobCreationCancelCode code,
+                          IPC::Sender* sender);
+
+  BlobTransportTemporaryHolder holder_;
+
+  DISALLOW_COPY_AND_ASSIGN(BlobTransportController);
+};
+
+}  // namespace content
+#endif  // CONTENT_CHILD_BLOB_STORAGE_BLOB_TRANSPORT_CONTROLLER_H_