1 /*
2  * Copyright (C) 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_HWUI_SIGNAL_H
18 #define ANDROID_HWUI_SIGNAL_H
19 
20 #include <stdint.h>
21 #include <sys/types.h>
22 #include <utils/threads.h>
23 
24 namespace android {
25 namespace uirenderer {
26 
27 class Signal {
28 public:
29     explicit Signal(Condition::WakeUpType type = Condition::WAKE_UP_ALL)
mType(type)30             : mType(type), mSignaled(false) {}
~Signal()31     ~Signal() {}
32 
signal()33     void signal() {
34         {
35             Mutex::Autolock l(mLock);
36             mSignaled = true;
37         }
38         mCondition.signal(mType);
39     }
40 
wait()41     void wait() {
42         Mutex::Autolock l(mLock);
43         while (!mSignaled) {
44             mCondition.wait(mLock);
45         }
46         mSignaled = false;
47     }
48 
49 private:
50     Condition::WakeUpType mType;
51     volatile bool mSignaled;
52     mutable Mutex mLock;
53     mutable Condition mCondition;
54 };
55 
56 };  // namespace uirenderer
57 };  // namespace android
58 
59 #endif  // ANDROID_HWUI_SIGNAL_H
60