DisconnectWaiter.h revision 49bfda1fbdf828a8ea63ae2c2fa25739f6e48527 
1/*
2 * Copyright 2013 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef ANDROID_DISCONNECT_WAITER_H
18#define ANDROID_DISCONNECT_WAITER_H
19
20#include <gui/IConsumerListener.h>
21
22#include <utils/Condition.h>
23#include <utils/Mutex.h>
24
25namespace android {
26
27// Note that GLConsumer will lose the notifications
28// onBuffersReleased and onFrameAvailable as there is currently
29// no way to forward the events.  This DisconnectWaiter will not let the
30// disconnect finish until finishDisconnect() is called.  It will
31// also block until a disconnect is called
32class DisconnectWaiter : public BnConsumerListener {
33public:
34    DisconnectWaiter () :
35        mWaitForDisconnect(false),
36        mPendingFrames(0) {
37    }
38
39    void waitForFrame() {
40        Mutex::Autolock lock(mMutex);
41        while (mPendingFrames == 0) {
42            mFrameCondition.wait(mMutex);
43        }
44        mPendingFrames--;
45    }
46
47    virtual void onFrameAvailable() {
48        Mutex::Autolock lock(mMutex);
49        mPendingFrames++;
50        mFrameCondition.signal();
51    }
52
53    virtual void onBuffersReleased() {
54        Mutex::Autolock lock(mMutex);
55        while (!mWaitForDisconnect) {
56            mDisconnectCondition.wait(mMutex);
57        }
58    }
59
60    virtual void onSidebandStreamChanged() {}
61
62    void finishDisconnect() {
63        Mutex::Autolock lock(mMutex);
64        mWaitForDisconnect = true;
65        mDisconnectCondition.signal();
66    }
67
68private:
69    Mutex mMutex;
70
71    bool mWaitForDisconnect;
72    Condition mDisconnectCondition;
73
74    int mPendingFrames;
75    Condition mFrameCondition;
76};
77
78} // namespace android
79
80#endif
81