reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (C) 2008 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 SkWriter32_DEFINED |
| 18 | #define SkWriter32_DEFINED |
| 19 | |
| 20 | #include "SkTypes.h" |
| 21 | |
| 22 | #include "SkScalar.h" |
| 23 | #include "SkPoint.h" |
| 24 | #include "SkRect.h" |
| 25 | |
| 26 | class SkStream; |
| 27 | class SkWStream; |
| 28 | |
| 29 | class SkWriter32 : SkNoncopyable { |
| 30 | public: |
| 31 | SkWriter32(size_t minSize) { |
| 32 | fMinSize = minSize; |
| 33 | fSize = 0; |
| 34 | fHead = fTail = NULL; |
| 35 | } |
| 36 | ~SkWriter32(); |
| 37 | |
| 38 | bool writeBool(bool value) { |
| 39 | this->writeInt(value); |
| 40 | return value; |
| 41 | } |
| 42 | |
| 43 | void writeInt(int32_t value) { |
| 44 | *(int32_t*)this->reserve(sizeof(value)) = value; |
| 45 | } |
| 46 | |
| 47 | void write8(int32_t value) { |
| 48 | *(int32_t*)this->reserve(sizeof(value)) = value & 0xFF; |
| 49 | } |
| 50 | |
| 51 | void write16(int32_t value) { |
| 52 | *(int32_t*)this->reserve(sizeof(value)) = value & 0xFFFF; |
| 53 | } |
| 54 | |
| 55 | void write32(int32_t value) { |
| 56 | *(int32_t*)this->reserve(sizeof(value)) = value; |
| 57 | } |
| 58 | |
| 59 | void writeScalar(SkScalar value) { |
| 60 | *(SkScalar*)this->reserve(sizeof(value)) = value; |
| 61 | } |
| 62 | |
| 63 | void writePoint(const SkPoint& pt) { |
| 64 | *(SkPoint*)this->reserve(sizeof(pt)) = pt; |
| 65 | } |
| 66 | |
| 67 | void writeRect(const SkRect& rect) { |
| 68 | *(SkRect*)this->reserve(sizeof(rect)) = rect; |
| 69 | } |
| 70 | |
| 71 | // write count bytes (must be a multiple of 4) |
| 72 | void writeMul4(const void* values, size_t size) { |
| 73 | SkASSERT(SkAlign4(size) == size); |
| 74 | // if we could query how much is avail in the current block, we might |
| 75 | // copy that much, and then alloc the rest. That would reduce the waste |
| 76 | // in the current block |
| 77 | memcpy(this->reserve(size), values, size); |
| 78 | } |
| 79 | |
| 80 | void writePad(const void* src, size_t size); |
| 81 | |
| 82 | // return the current offset (will always be a multiple of 4) |
| 83 | uint32_t size() const { return fSize; } |
| 84 | void reset(); |
| 85 | uint32_t* reserve(size_t size); // size MUST be multiple of 4 |
| 86 | |
| 87 | // return the address of the 4byte int at the specified offset (which must |
| 88 | // be a multiple of 4. This does not allocate any new space, so the returned |
| 89 | // address is only valid for 1 int. |
| 90 | uint32_t* peek32(size_t offset); |
| 91 | |
| 92 | // copy into a single buffer (allocated by caller). Must be at least size() |
| 93 | void flatten(void* dst) const; |
| 94 | |
| 95 | // read from the stream, and write up to length bytes. Return the actual |
| 96 | // number of bytes written. |
| 97 | size_t readFromStream(SkStream*, size_t length); |
| 98 | |
| 99 | bool writeToStream(SkWStream*); |
| 100 | |
| 101 | private: |
| 102 | size_t fMinSize; |
| 103 | uint32_t fSize; |
| 104 | |
| 105 | struct Block; |
| 106 | Block* fHead; |
| 107 | Block* fTail; |
| 108 | |
| 109 | Block* newBlock(size_t bytes); |
| 110 | }; |
| 111 | |
| 112 | #endif |