blob: becffb9ad3878105791ea785a07ac15c77406df0 [file] [log] [blame]
/*
* Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#ifndef MODULES_INCLUDE_MODULE_H_
#define MODULES_INCLUDE_MODULE_H_
#include "typedefs.h" // NOLINT(build/include)
namespace webrtc {
class ProcessThread;
class Module {
public:
// Returns the number of milliseconds until the module wants a worker
// thread to call Process.
// This method is called on the same worker thread as Process will
// be called on.
// TODO(tommi): Almost all implementations of this function, need to know
// the current tick count. Consider passing it as an argument. It could
// also improve the accuracy of when the next callback occurs since the
// thread that calls Process() will also have it's tick count reference
// which might not match with what the implementations use.
virtual int64_t TimeUntilNextProcess() = 0;
// Process any pending tasks such as timeouts.
// Called on a worker thread.
virtual void Process() = 0;
// This method is called when the module is attached to a *running* process
// thread or detached from one. In the case of detaching, |process_thread|
// will be nullptr.
//
// This method will be called in the following cases:
//
// * Non-null process_thread:
// * ProcessThread::RegisterModule() is called while the thread is running.
// * ProcessThread::Start() is called and RegisterModule has previously
// been called. The thread will be started immediately after notifying
// all modules.
//
// * Null process_thread:
// * ProcessThread::DeRegisterModule() is called while the thread is
// running.
// * ProcessThread::Stop() was called and the thread has been stopped.
//
// NOTE: This method is not called from the worker thread itself, but from
// the thread that registers/deregisters the module or calls Start/Stop.
virtual void ProcessThreadAttached(ProcessThread* process_thread) {}
protected:
virtual ~Module() {}
};
// Reference counted version of the Module interface.
class RefCountedModule : public Module {
public:
// Increase the reference count by one.
// Returns the incremented reference count.
virtual int32_t AddRef() const = 0;
// Decrease the reference count by one.
// Returns the decreased reference count.
// Returns 0 if the last reference was just released.
// When the reference count reaches 0 the object will self-destruct.
virtual int32_t Release() const = 0;
protected:
~RefCountedModule() override = default;
};
} // namespace webrtc
#endif // MODULES_INCLUDE_MODULE_H_