1076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian/* 2076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian * Copyright (C) 2007 The Android Open Source Project 3076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian * 4076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian * Licensed under the Apache License, Version 2.0 (the "License"); 5076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian * you may not use this file except in compliance with the License. 6076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian * You may obtain a copy of the License at 7076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian * 8076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian * http://www.apache.org/licenses/LICENSE-2.0 9076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian * 10076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian * Unless required by applicable law or agreed to in writing, software 11076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian * distributed under the License is distributed on an "AS IS" BASIS, 12076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian * See the License for the specific language governing permissions and 14076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian * limitations under the License. 15076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian */ 16076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian 17076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian#ifndef ANDROID_UTILS_SINGLETON_H 18076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian#define ANDROID_UTILS_SINGLETON_H 19076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian 20076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian#include <stdint.h> 21076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian#include <sys/types.h> 22076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian#include <utils/threads.h> 235c78b6861fd4c9246cc88d37178a5567fb668f5bRomain Guy#include <cutils/compiler.h> 24076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian 25076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopiannamespace android { 26076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian// --------------------------------------------------------------------------- 27076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian 28076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopiantemplate <typename TYPE> 295c78b6861fd4c9246cc88d37178a5567fb668f5bRomain Guyclass ANDROID_API Singleton 30076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian{ 31076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopianpublic: 32076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian static TYPE& getInstance() { 33076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian Mutex::Autolock _l(sLock); 34076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian TYPE* instance = sInstance; 35076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian if (instance == 0) { 36076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian instance = new TYPE(); 37076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian sInstance = instance; 38076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian } 39076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian return *instance; 40076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian } 414e0c1f27fdefdd9b0208ea64542c1e39d9327eb9Romain Guy 424e0c1f27fdefdd9b0208ea64542c1e39d9327eb9Romain Guy static bool hasInstance() { 434e0c1f27fdefdd9b0208ea64542c1e39d9327eb9Romain Guy Mutex::Autolock _l(sLock); 444e0c1f27fdefdd9b0208ea64542c1e39d9327eb9Romain Guy return sInstance != 0; 454e0c1f27fdefdd9b0208ea64542c1e39d9327eb9Romain Guy } 46076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian 47076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopianprotected: 48076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian ~Singleton() { }; 49076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian Singleton() { }; 50076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian 51076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopianprivate: 52076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian Singleton(const Singleton&); 53076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian Singleton& operator = (const Singleton&); 54076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian static Mutex sLock; 55076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian static TYPE* sInstance; 56076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian}; 57076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian 589f88afb013a7560bf1362d7999a4609e38d0ea77Mathias Agopian/* 599f88afb013a7560bf1362d7999a4609e38d0ea77Mathias Agopian * use ANDROID_SINGLETON_STATIC_INSTANCE(TYPE) in your implementation file 609f88afb013a7560bf1362d7999a4609e38d0ea77Mathias Agopian * (eg: <TYPE>.cpp) to create the static instance of Singleton<>'s attributes, 619f88afb013a7560bf1362d7999a4609e38d0ea77Mathias Agopian * and avoid to have a copy of them in each compilation units Singleton<TYPE> 629f88afb013a7560bf1362d7999a4609e38d0ea77Mathias Agopian * is used. 63b8510b98b5eb92333157db1359df6f2bbbfb2b39Mathias Agopian * NOTE: we use a version of Mutex ctor that takes a parameter, because 64b8510b98b5eb92333157db1359df6f2bbbfb2b39Mathias Agopian * for some unknown reason using the default ctor doesn't emit the variable! 659f88afb013a7560bf1362d7999a4609e38d0ea77Mathias Agopian */ 669f88afb013a7560bf1362d7999a4609e38d0ea77Mathias Agopian 67b8510b98b5eb92333157db1359df6f2bbbfb2b39Mathias Agopian#define ANDROID_SINGLETON_STATIC_INSTANCE(TYPE) \ 68b8510b98b5eb92333157db1359df6f2bbbfb2b39Mathias Agopian template<> Mutex Singleton< TYPE >::sLock(Mutex::PRIVATE); \ 69114e968482a02b9153d9a236376efb5cd43f4a9aTareq A. Siraj template<> TYPE* Singleton< TYPE >::sInstance(0); \ 70114e968482a02b9153d9a236376efb5cd43f4a9aTareq A. Siraj template class Singleton< TYPE >; 719f88afb013a7560bf1362d7999a4609e38d0ea77Mathias Agopian 729f88afb013a7560bf1362d7999a4609e38d0ea77Mathias Agopian 73076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian// --------------------------------------------------------------------------- 74076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian}; // namespace android 75076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian 76076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian#endif // ANDROID_UTILS_SINGLETON_H 77076b1cc3a9b90aa5b381a1ed268ca0b548444c9bMathias Agopian 78