1 /* 2 * Copyright (C) 2007 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_BARRIER_H 18 #define ANDROID_BARRIER_H 19 20 #include <stdint.h> 21 #include <sys/types.h> 22 #include <utils/threads.h> 23 24 namespace android { 25 26 class Barrier 27 { 28 public: 29 inline Barrier() : state(CLOSED) { } 30 inline ~Barrier() { } 31 void open() { 32 Mutex::Autolock _l(lock); 33 state = OPENED; 34 cv.broadcast(); 35 } 36 void close() { 37 Mutex::Autolock _l(lock); 38 state = CLOSED; 39 } 40 void wait() const { 41 Mutex::Autolock _l(lock); 42 while (state == CLOSED) { 43 cv.wait(lock); 44 } 45 } 46 private: 47 enum { OPENED, CLOSED }; 48 mutable Mutex lock; 49 mutable Condition cv; 50 volatile int state; 51 }; 52 53 }; // namespace android 54 55 #endif // ANDROID_BARRIER_H 56
