gecko/dom/media/MediaDecoderStateMachineScheduler.h
Bobby Holley 4ffe849a5a Bug 1135785 - Return samples on state machine thread. r=cpearce
This is necessary because we're going to want to start disconnecting sample
and seek requests directly from the state machine thread, and the machinery
asserts that disconnection happens on the same thread as resolution.

More generally, this is the right thing to do architecturally, and will help
wean us off the monitor.
2015-03-01 19:33:49 -08:00

88 lines
2.7 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef MediaDecoderStateMachineScheduler_h__
#define MediaDecoderStateMachineScheduler_h__
#include "nsCOMPtr.h"
#include "mozilla/TimeStamp.h"
#include "mozilla/DebugOnly.h"
class nsITimer;
class nsIEventTarget;
namespace mozilla {
class ReentrantMonitor;
class MediaDecoderStateMachineScheduler {
enum State {
SCHEDULER_STATE_NONE,
SCHEDULER_STATE_FROZEN,
SCHEDULER_STATE_FROZEN_WITH_PENDING_TASK,
SCHEDULER_STATE_SHUTDOWN
};
public:
NS_INLINE_DECL_THREADSAFE_REFCOUNTING(MediaDecoderStateMachineScheduler)
MediaDecoderStateMachineScheduler(ReentrantMonitor& aMonitor,
nsresult (*aTimeoutCallback)(void*),
void* aClosure, bool aRealTime);
nsresult Init();
nsresult Schedule(int64_t aUsecs = 0);
void ScheduleAndShutdown();
nsresult TimeoutExpired(int aTimerId);
void FreezeScheduling();
void ThawScheduling();
bool OnStateMachineThread() const;
bool IsScheduled() const;
bool IsRealTime() const {
return mRealTime;
}
nsIEventTarget* GetStateMachineThread() const {
return mEventTarget;
}
bool IsFrozen() const {
return mState == SCHEDULER_STATE_FROZEN ||
mState == SCHEDULER_STATE_FROZEN_WITH_PENDING_TASK;
}
private:
~MediaDecoderStateMachineScheduler();
void ResetTimer();
// Callback function provided by MediaDecoderStateMachine to run
// state machine cycles.
nsresult (*const mTimeoutCallback)(void*);
// Since StateMachineScheduler will never outlive the state machine,
// it is safe to keep a raw pointer only to avoid reference cycles.
void* const mClosure;
// True is we are decoding a realtime stream, like a camera stream
const bool mRealTime;
// Monitor of the decoder
ReentrantMonitor& mMonitor;
// State machine thread
const nsCOMPtr<nsIEventTarget> mEventTarget;
// Timer to schedule callbacks to run the state machine cycles.
nsCOMPtr<nsITimer> mTimer;
// Timestamp at which the next state machine cycle will run.
TimeStamp mTimeout;
// The id of timer tasks, timer callback will only run if id matches.
int mTimerId;
// No more state machine cycles in shutdown state.
State mState;
// Used to check if state machine cycles are running in sequence.
DebugOnly<bool> mInRunningStateMachine;
};
} // namespace mozilla
#endif // MediaDecoderStateMachineScheduler_h__