1 2 /* 3 * Copyright 2006 The Android Open Source Project 4 * 5 * Use of this source code is governed by a BSD-style license that can be 6 * found in the LICENSE file. 7 */ 8 9 10 #ifndef SkChunkAlloc_DEFINED 11 #define SkChunkAlloc_DEFINED 12 13 #include "SkTypes.h" 14 15 class SkChunkAlloc : SkNoncopyable { 16 public: 17 SkChunkAlloc(size_t minSize); 18 ~SkChunkAlloc(); 19 20 /** 21 * Free up all allocated blocks. This invalidates all returned 22 * pointers. 23 */ 24 void reset(); 25 /** 26 * Reset to 0 used bytes preserving as much memory as possible. 27 * This invalidates all returned pointers. 28 */ 29 void rewind(); 30 31 enum AllocFailType { 32 kReturnNil_AllocFailType, 33 kThrow_AllocFailType 34 }; 35 36 void* alloc(size_t bytes, AllocFailType); 37 void* allocThrow(size_t bytes) { 38 return this->alloc(bytes, kThrow_AllocFailType); 39 } 40 41 /** Call this to unalloc the most-recently allocated ptr by alloc(). On 42 success, the number of bytes freed is returned, or 0 if the block could 43 not be unallocated. This is a hint to the underlying allocator that 44 the previous allocation may be reused, but the implementation is free 45 to ignore this call (and return 0). 46 */ 47 size_t unalloc(void* ptr); 48 49 size_t totalCapacity() const { return fTotalCapacity; } 50 size_t totalUsed() const { return fTotalUsed; } 51 SkDEBUGCODE(int blockCount() const { return fBlockCount; }) 52 SkDEBUGCODE(size_t totalLost() const { return fTotalLost; }) 53 54 /** 55 * Returns true if the specified address is within one of the chunks, and 56 * has at least 1-byte following the address (i.e. if addr points to the 57 * end of a chunk, then contains() will return false). 58 */ 59 bool contains(const void* addr) const; 60 61 private: 62 struct Block; 63 64 Block* fBlock; 65 size_t fMinSize; 66 size_t fChunkSize; 67 size_t fTotalCapacity; 68 size_t fTotalUsed; // will be <= fTotalCapacity 69 SkDEBUGCODE(int fBlockCount;) 70 SkDEBUGCODE(size_t fTotalLost;) // will be <= fTotalCapacity 71 72 Block* newBlock(size_t bytes, AllocFailType ftype); 73 Block* addBlockIfNecessary(size_t bytes, AllocFailType ftype); 74 75 SkDEBUGCODE(void validate();) 76 }; 77 78 #endif 79
