1 /* 2 * Copyright (C) 2014 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 LINKEDBLOCKINGQUEUE_H_ 18 #define LINKEDBLOCKINGQUEUE_H_ 19 20 #include <utils/List.h> 21 #include <utils/Mutex.h> 22 #include <utils/Condition.h> 23 24 namespace android { 25 26 template<typename T> 27 class LinkedBlockingQueue { 28 List<T> mList; 29 Mutex mLock; 30 Condition mContentAvailableCondition; 31 32 T front(bool remove) { 33 Mutex::Autolock autolock(mLock); 34 while (mList.empty()) { 35 mContentAvailableCondition.wait(mLock); 36 } 37 T e = *(mList.begin()); 38 if (remove) { 39 mList.erase(mList.begin()); 40 } 41 return e; 42 } 43 44 DISALLOW_EVIL_CONSTRUCTORS(LinkedBlockingQueue); 45 46 public: 47 LinkedBlockingQueue() { 48 } 49 50 ~LinkedBlockingQueue() { 51 } 52 53 bool empty() { 54 Mutex::Autolock autolock(mLock); 55 return mList.empty(); 56 } 57 58 void clear() { 59 Mutex::Autolock autolock(mLock); 60 mList.clear(); 61 } 62 63 T peek() { 64 return front(false); 65 } 66 67 T take() { 68 return front(true); 69 } 70 71 void push(T e) { 72 Mutex::Autolock autolock(mLock); 73 mList.push_back(e); 74 mContentAvailableCondition.signal(); 75 } 76 }; 77 78 } /* namespace android */ 79 #endif /* LINKEDBLOCKINGQUEUE_H_ */ 80
