blob: b667bfc68afbfc97fb100b7e688e3377916901c8 [file] [log] [blame]
/*
* Copyright (c) 2011 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_UTILITY_SOURCE_PROCESS_THREAD_IMPL_H_
#define MODULES_UTILITY_SOURCE_PROCESS_THREAD_IMPL_H_
#include <stdint.h>
#include <list>
#include <memory>
#include <queue>
#include "api/sequence_checker.h"
#include "api/task_queue/queued_task.h"
#include "modules/include/module.h"
#include "modules/utility/include/process_thread.h"
#include "rtc_base/deprecated/recursive_critical_section.h"
#include "rtc_base/event.h"
#include "rtc_base/location.h"
#include "rtc_base/platform_thread.h"
namespace webrtc {
class ProcessThreadImpl : public ProcessThread {
public:
explicit ProcessThreadImpl(const char* thread_name);
~ProcessThreadImpl() override;
void Start() override;
void Stop() override;
void WakeUp(Module* module) override;
void PostTask(std::unique_ptr<QueuedTask> task) override;
void PostDelayedTask(std::unique_ptr<QueuedTask> task,
uint32_t milliseconds) override;
void RegisterModule(Module* module, const rtc::Location& from) override;
void DeRegisterModule(Module* module) override;
protected:
bool Process();
private:
struct ModuleCallback {
ModuleCallback() = delete;
ModuleCallback(ModuleCallback&& cb) = default;
ModuleCallback(const ModuleCallback& cb) = default;
ModuleCallback(Module* module, const rtc::Location& location)
: module(module), location(location) {}
bool operator==(const ModuleCallback& cb) const {
return cb.module == module;
}
Module* const module;
int64_t next_callback = 0; // Absolute timestamp.
const rtc::Location location;
private:
ModuleCallback& operator=(ModuleCallback&);
};
struct DelayedTask {
DelayedTask(int64_t run_at_ms, std::unique_ptr<QueuedTask> task)
: run_at_ms(run_at_ms), task(task.release()) {}
friend bool operator<(const DelayedTask& lhs, const DelayedTask& rhs) {
// Earliest DelayedTask should be at the top of the priority queue.
return lhs.run_at_ms > rhs.run_at_ms;
}
int64_t run_at_ms;
// DelayedTask owns the |task|, but some delayed tasks must be removed from
// the std::priority_queue, but mustn't be deleted. std::priority_queue does
// not give non-const access to the values, so storing unique_ptr would
// delete the task as soon as it is remove from the priority queue.
// Thus lifetime of the |task| is managed manually.
QueuedTask* task;
};
typedef std::list<ModuleCallback> ModuleList;
void Delete() override;
// The part of Stop processing that doesn't need any locking.
void StopNoLocks();
void WakeUpNoLocks(Module* module);
void WakeUpInternal(Module* module) RTC_EXCLUSIVE_LOCKS_REQUIRED(mutex_);
// Members protected by this mutex are accessed on the constructor thread and
// on the spawned process thread, and locking is needed only while the process
// thread is running.
Mutex mutex_;
SequenceChecker thread_checker_;
rtc::Event wake_up_;
rtc::PlatformThread thread_;
ModuleList modules_ RTC_GUARDED_BY(mutex_);
// Set to true when calling Process, to allow reentrant calls to WakeUp.
bool holds_mutex_ RTC_GUARDED_BY(this) = false;
std::queue<QueuedTask*> queue_;
std::priority_queue<DelayedTask> delayed_tasks_ RTC_GUARDED_BY(mutex_);
// The `stop_` flag is modified only by the construction thread, protected by
// `thread_checker_`. It is read also by the spawned `thread_`. The latter
// thread must take `mutex_` before access, and for thread safety, the
// constructor thread needs to take `mutex_` when it modifies `stop_` and
// `thread_` is running. Annotations like RTC_GUARDED_BY doesn't support this
// usage pattern.
bool stop_ RTC_GUARDED_BY(mutex_);
const char* thread_name_;
};
} // namespace webrtc
#endif // MODULES_UTILITY_SOURCE_PROCESS_THREAD_IMPL_H_