[BlobAsync] Asynchronous Blob Construction Final Patch

content/browser/blob_storage/blob_dispatcher_host.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_BROWSER_BLOB_STORAGE_BLOB_DISPATCHER_HOST_H_
+#define CONTENT_BROWSER_BLOB_STORAGE_BLOB_DISPATCHER_HOST_H_
+
+#include <set>
+#include <string>
+#include <vector>
+
+#include "base/files/file.h"
+#include "base/gtest_prod_util.h"
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "base/memory/shared_memory_handle.h"
+#include "content/common/content_export.h"
+#include "content/public/browser/browser_message_filter.h"
+#include "storage/browser/blob/blob_async_builder_host.h"
+#include "storage/browser/blob/blob_transport_result.h"
+#include "storage/common/blob_storage/blob_storage_constants.h"
+
+class GURL;
+
+namespace IPC {
+class Sender;
+}
+
+namespace storage {
+class DataElement;
+class BlobDataBuilder;
+struct BlobItemBytesRequest;
+struct BlobItemBytesResponse;
+class BlobStorageContext;
+}
+
+namespace content {
+class ChromeBlobStorageContext;
+
+// This class's responsibility is to listen for and dispatch blob storage
+// messages and handle logistics of blob storage for a single child process.
+// When the child process terminates all blob references attributable to
+// that process go away upon destruction of the instance.
+// This lives in the browser process, is single threaded (IO thread), and there
+// is one per child process.
+class CONTENT_EXPORT BlobDispatcherHost : public BrowserMessageFilter {
+ public:
+  explicit BlobDispatcherHost(ChromeBlobStorageContext* blob_storage_context);
+
+  // BrowserMessageFilter implementation.
+  void OnChannelClosing() override;
+  bool OnMessageReceived(const IPC::Message& message) override;
+
+ protected:
+  ~BlobDispatcherHost() override;
+
+ private:
+  friend class base::RefCountedThreadSafe<BlobDispatcherHost>;
+  friend class BlobDispatcherHostTest;
+  FRIEND_TEST_ALL_PREFIXES(BlobDispatcherHostTest, EmptyUUIDs);
+  FRIEND_TEST_ALL_PREFIXES(BlobDispatcherHostTest, OnCancelBuildingBlob);
+  FRIEND_TEST_ALL_PREFIXES(BlobDispatcherHostTest,
+                           BlobReferenceWhileConstructing);
+  FRIEND_TEST_ALL_PREFIXES(BlobDispatcherHostTest,
+                           BlobReferenceWhileShortcutConstructing);
+  FRIEND_TEST_ALL_PREFIXES(BlobDispatcherHostTest,
+                           BlobReferenceWhileConstructingCancelled);
+  FRIEND_TEST_ALL_PREFIXES(BlobDispatcherHostTest, BlobDestructionEdgeCases);
+
+  typedef std::map<std::string, int> BlobReferenceMap;
+
+  void OnRegisterBlobUUID(const std::string& uuid,
+                          const std::string& content_type,
+                          const std::string& content_disposition);
+  void OnStartBuildingBlob(
+      const std::string& uuid,
+      const std::vector<storage::DataElement>& descriptions);
+  void OnMemoryItemResponse(
+      const std::string& uuid,
+      const std::vector<storage::BlobItemBytesResponse>& response);
+  void OnCancelBuildingBlob(const std::string& uuid,
+                            const storage::IPCBlobCreationCancelCode code);
+
+  void OnIncrementBlobRefCount(const std::string& uuid);
+  void OnDecrementBlobRefCount(const std::string& uuid);
+  void OnRegisterPublicBlobURL(const GURL& public_url, const std::string& uuid);
+  void OnRevokePublicBlobURL(const GURL& public_url);
+
+  storage::BlobStorageContext* context();
+
+  // We split this from OnStartBuildingBlob so we can share the code in the
+  // SendIPCResponse method.
+  storage::BlobTransportResult StartBuildingBlob(
+      const std::string& uuid,
+      const std::vector<storage::DataElement>& descriptions);
+
+  // We split this from OnMemoryItemResponse so we can share the code in the
+  // SendIPCResponse method.
+  storage::BlobTransportResult MemoryItemResponse(
+      const std::string& uuid,
+      const std::vector<storage::BlobItemBytesResponse>& response);
+
+  void SendMemoryRequest(
+      const std::string& uuid,
+      const std::vector<storage::BlobItemBytesRequest>& requests,
+      const std::vector<base::SharedMemoryHandle>& memory_handles,
+      std::vector<base::File>* files);
+
+  // Send the appropriate IPC response to the renderer for the given result.
+  void SendIPCResponse(const std::string& uuid,
+                       storage::BlobTransportResult result);
+
+  bool IsInUseInHost(const std::string& uuid);
+  bool IsBeingBuiltInHost(const std::string& uuid);
+  bool IsUrlRegisteredInHost(const GURL& blob_url);
+
+  // Unregisters all blobs and urls that were registered in this host.
+  void ClearHostFromBlobStorageContext();
+
+  // 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_;
+
+  scoped_refptr<ChromeBlobStorageContext> blob_storage_context_;
+  storage::BlobAsyncBuilderHost async_builder_;
+
+  DISALLOW_COPY_AND_ASSIGN(BlobDispatcherHost);
+};
+}  // namespace content
+#endif  // CONTENT_BROWSER_BLOB_STORAGE_BLOB_DISPATCHER_HOST_H_