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_FRAME_WAITER_H
18 #define ANDROID_FRAME_WAITER_H
19 
20 #include <gui/GLConsumer.h>
21 
22 namespace android {
23 
24 class FrameWaiter : public GLConsumer::FrameAvailableListener {
25 public:
FrameWaiter()26     FrameWaiter():
27             mPendingFrames(0) {
28     }
29 
waitForFrame()30     void waitForFrame() {
31         Mutex::Autolock lock(mMutex);
32         while (mPendingFrames == 0) {
33             mCondition.wait(mMutex);
34         }
35         mPendingFrames--;
36     }
37 
onFrameAvailable(const BufferItem &)38     virtual void onFrameAvailable(const BufferItem& /* item */) {
39         Mutex::Autolock lock(mMutex);
40         mPendingFrames++;
41         mCondition.signal();
42     }
43 
44 private:
45     int mPendingFrames;
46     Mutex mMutex;
47     Condition mCondition;
48 };
49 
50 } // namespace android
51 
52 #endif
53