Jean-Baptiste Queru | 1202e07 | 2009-11-12 18:46:07 -0800 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (C) 2009 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 | |
| 18 | #ifndef GRALLOC_ALLOCATOR_H_ |
| 19 | #define GRALLOC_ALLOCATOR_H_ |
| 20 | |
| 21 | #include <stdint.h> |
| 22 | #include <sys/types.h> |
| 23 | |
| 24 | #include "gr.h" |
| 25 | |
| 26 | // ---------------------------------------------------------------------------- |
| 27 | |
| 28 | /* |
| 29 | * A simple templatized doubly linked-list implementation |
| 30 | */ |
| 31 | |
| 32 | template <typename NODE> |
| 33 | class LinkedList |
| 34 | { |
| 35 | NODE* mFirst; |
| 36 | NODE* mLast; |
| 37 | |
| 38 | public: |
| 39 | LinkedList() : mFirst(0), mLast(0) { } |
| 40 | bool isEmpty() const { return mFirst == 0; } |
| 41 | NODE const* head() const { return mFirst; } |
| 42 | NODE* head() { return mFirst; } |
| 43 | NODE const* tail() const { return mLast; } |
| 44 | NODE* tail() { return mLast; } |
| 45 | |
| 46 | void insertAfter(NODE* node, NODE* newNode) { |
| 47 | newNode->prev = node; |
| 48 | newNode->next = node->next; |
| 49 | if (node->next == 0) mLast = newNode; |
| 50 | else node->next->prev = newNode; |
| 51 | node->next = newNode; |
| 52 | } |
| 53 | |
| 54 | void insertBefore(NODE* node, NODE* newNode) { |
| 55 | newNode->prev = node->prev; |
| 56 | newNode->next = node; |
| 57 | if (node->prev == 0) mFirst = newNode; |
| 58 | else node->prev->next = newNode; |
| 59 | node->prev = newNode; |
| 60 | } |
| 61 | |
| 62 | void insertHead(NODE* newNode) { |
| 63 | if (mFirst == 0) { |
| 64 | mFirst = mLast = newNode; |
| 65 | newNode->prev = newNode->next = 0; |
| 66 | } else { |
| 67 | newNode->prev = 0; |
| 68 | newNode->next = mFirst; |
| 69 | mFirst->prev = newNode; |
| 70 | mFirst = newNode; |
| 71 | } |
| 72 | } |
| 73 | |
| 74 | void insertTail(NODE* newNode) { |
| 75 | if (mLast == 0) { |
| 76 | insertHead(newNode); |
| 77 | } else { |
| 78 | newNode->prev = mLast; |
| 79 | newNode->next = 0; |
| 80 | mLast->next = newNode; |
| 81 | mLast = newNode; |
| 82 | } |
| 83 | } |
| 84 | |
| 85 | NODE* remove(NODE* node) { |
| 86 | if (node->prev == 0) mFirst = node->next; |
| 87 | else node->prev->next = node->next; |
| 88 | if (node->next == 0) mLast = node->prev; |
| 89 | else node->next->prev = node->prev; |
| 90 | return node; |
| 91 | } |
| 92 | }; |
| 93 | |
| 94 | class SimpleBestFitAllocator |
| 95 | { |
| 96 | public: |
| 97 | |
| 98 | SimpleBestFitAllocator(); |
| 99 | SimpleBestFitAllocator(size_t size); |
| 100 | ~SimpleBestFitAllocator(); |
| 101 | |
| 102 | ssize_t setSize(size_t size); |
| 103 | |
| 104 | ssize_t allocate(size_t size, uint32_t flags = 0); |
| 105 | ssize_t deallocate(size_t offset); |
| 106 | size_t size() const; |
| 107 | |
| 108 | private: |
| 109 | struct chunk_t { |
| 110 | chunk_t(size_t start, size_t size) |
| 111 | : start(start), size(size), free(1), prev(0), next(0) { |
| 112 | } |
| 113 | size_t start; |
| 114 | size_t size : 28; |
| 115 | int free : 4; |
| 116 | mutable chunk_t* prev; |
| 117 | mutable chunk_t* next; |
| 118 | }; |
| 119 | |
| 120 | ssize_t alloc(size_t size, uint32_t flags); |
| 121 | chunk_t* dealloc(size_t start); |
| 122 | |
| 123 | static const int kMemoryAlign; |
| 124 | mutable Locker mLock; |
| 125 | LinkedList<chunk_t> mList; |
| 126 | size_t mHeapSize; |
| 127 | }; |
| 128 | |
| 129 | #endif /* GRALLOC_ALLOCATOR_H_ */ |