1 /* 2 * Copyright (C) 2010 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 UTILS_POOL_H 18 #define UTILS_POOL_H 19 20 #include <utils/TypeHelpers.h> 21 22 namespace android { 23 24 class PoolImpl { 25 public: 26 PoolImpl(size_t objSize); 27 ~PoolImpl(); 28 29 void* allocImpl(); 30 void freeImpl(void* obj); 31 32 private: 33 size_t mObjSize; 34 }; 35 36 /* 37 * A homogeneous typed memory pool for fixed size objects. 38 * Not intended to be thread-safe. 39 */ 40 template<typename T> 41 class Pool : private PoolImpl { 42 public: 43 /* Creates an initially empty pool. */ Pool()44 Pool() : PoolImpl(sizeof(T)) { } 45 46 /* Destroys the pool. 47 * Assumes that the pool is empty. */ ~Pool()48 ~Pool() { } 49 50 /* Allocates an object from the pool, growing the pool if needed. */ alloc()51 inline T* alloc() { 52 void* mem = allocImpl(); 53 if (! traits<T>::has_trivial_ctor) { 54 return new (mem) T(); 55 } else { 56 return static_cast<T*>(mem); 57 } 58 } 59 60 /* Frees an object from the pool. */ free(T * obj)61 inline void free(T* obj) { 62 if (! traits<T>::has_trivial_dtor) { 63 obj->~T(); 64 } 65 freeImpl(obj); 66 } 67 }; 68 69 } // namespace android 70 71 #endif // UTILS_POOL_H 72