blob: 28370dba9ed9bdc251425562f72365e6fcdd0aa1 [file] [log] [blame]
// Copyright 2015 The Chromium OS Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "trunks/command_transceiver.h"
#include <string>
#include <base/memory/ref_counted.h>
#include <base/memory/weak_ptr.h>
#include <base/sequenced_task_runner.h>
#include "trunks/trunks_export.h"
namespace trunks {
// Sends commands to another CommandTransceiver on a background thread. Response
// callbacks are called on the original calling thread.
// Example:
// base::Thread background_thread("my thread");
// ...
// BackgroundCommandTransceiver background_transceiver(
// next_transceiver,
// background_thread.message_loop_proxy());
// ...
// background_transceiver.SendCommand(my_command, MyCallback);
class TRUNKS_EXPORT BackgroundCommandTransceiver : public CommandTransceiver {
// All commands will be forwarded to |next_transceiver| on |task_runner|,
// regardless of whether the synchronous or asynchronous method is used. This
// class will hold a reference count to |task_runner|. If |task_runner| is
// nullptr, all commands will be forwarded on the current thread. This class
// does not take ownership of |next_transceiver|; it must remain valid for
// the lifetime of the object.
explicit BackgroundCommandTransceiver(
CommandTransceiver* next_transceiver,
const scoped_refptr<base::SequencedTaskRunner>& task_runner);
BackgroundCommandTransceiver(const BackgroundCommandTransceiver&) = delete;
BackgroundCommandTransceiver& operator=(const BackgroundCommandTransceiver&) =
~BackgroundCommandTransceiver() override;
// CommandTranceiver methods.
void SendCommand(const std::string& command,
const ResponseCallback& callback) override;
std::string SendCommandAndWait(const std::string& command) override;
// Sends a |command| to the |next_transceiver_| and invokes a |callback| with
// the command response.
void SendCommandTask(const std::string& command,
const ResponseCallback& callback);
base::WeakPtr<BackgroundCommandTransceiver> GetWeakPtr() {
return weak_factory_.GetWeakPtr();
CommandTransceiver* next_transceiver_;
scoped_refptr<base::SequencedTaskRunner> task_runner_;
// Declared last so weak pointers are invalidated first on destruction.
base::WeakPtrFactory<BackgroundCommandTransceiver> weak_factory_;
} // namespace trunks