reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 1 | /* libs/corecg/SkBuffer.cpp |
| 2 | ** |
| 3 | ** Copyright 2006, The Android Open Source Project |
| 4 | ** |
| 5 | ** Licensed under the Apache License, Version 2.0 (the "License"); |
| 6 | ** you may not use this file except in compliance with the License. |
| 7 | ** You may obtain a copy of the License at |
| 8 | ** |
| 9 | ** http://www.apache.org/licenses/LICENSE-2.0 |
| 10 | ** |
| 11 | ** Unless required by applicable law or agreed to in writing, software |
| 12 | ** distributed under the License is distributed on an "AS IS" BASIS, |
| 13 | ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 14 | ** See the License for the specific language governing permissions and |
| 15 | ** limitations under the License. |
| 16 | */ |
| 17 | |
| 18 | #include "SkBuffer.h" |
| 19 | |
| 20 | //////////////////////////////////////////////////////////////////////////////////////// |
| 21 | |
| 22 | void SkRBuffer::readNoSizeCheck(void* buffer, size_t size) |
| 23 | { |
| 24 | SkASSERT((fData != 0 && fStop == 0) || fPos + size <= fStop); |
| 25 | if (buffer) |
| 26 | memcpy(buffer, fPos, size); |
| 27 | fPos += size; |
| 28 | } |
| 29 | |
| 30 | const void* SkRBuffer::skip(size_t size) |
| 31 | { |
| 32 | const void* result = fPos; |
| 33 | readNoSizeCheck(NULL, size); |
| 34 | return result; |
| 35 | } |
| 36 | |
| 37 | size_t SkRBuffer::skipToAlign4() |
| 38 | { |
| 39 | size_t pos = this->pos(); |
| 40 | size_t n = SkAlign4(pos) - pos; |
| 41 | fPos += n; |
| 42 | return n; |
| 43 | } |
| 44 | |
| 45 | void* SkWBuffer::skip(size_t size) |
| 46 | { |
| 47 | void* result = fPos; |
| 48 | writeNoSizeCheck(NULL, size); |
| 49 | return fData == NULL ? NULL : result; |
| 50 | } |
| 51 | |
| 52 | void SkWBuffer::writeNoSizeCheck(const void* buffer, size_t size) |
| 53 | { |
| 54 | SkASSERT(fData == 0 || fStop == 0 || fPos + size <= fStop); |
| 55 | if (fData && buffer) |
| 56 | memcpy(fPos, buffer, size); |
| 57 | fPos += size; |
| 58 | } |
| 59 | |
| 60 | size_t SkWBuffer::padToAlign4() |
| 61 | { |
| 62 | size_t pos = this->pos(); |
| 63 | size_t n = SkAlign4(pos) - pos; |
| 64 | |
| 65 | if (n && fData) |
| 66 | { |
| 67 | char* p = fPos; |
| 68 | char* stop = p + n; |
| 69 | do { |
| 70 | *p++ = 0; |
| 71 | } while (p < stop); |
| 72 | } |
| 73 | fPos += n; |
| 74 | return n; |
| 75 | } |
| 76 | |
| 77 | #if 0 |
| 78 | #ifdef SK_DEBUG |
| 79 | static void AssertBuffer32(const void* buffer) |
| 80 | { |
| 81 | SkASSERT(buffer); |
| 82 | SkASSERT(((size_t)buffer & 3) == 0); |
| 83 | } |
| 84 | #else |
| 85 | #define AssertBuffer32(buffer) |
| 86 | #endif |
| 87 | |
| 88 | void* sk_buffer_write_int32(void* buffer, int32_t value) |
| 89 | { |
| 90 | AssertBuffer32(buffer); |
| 91 | *(int32_t*)buffer = value; |
| 92 | return (char*)buffer + sizeof(int32_t); |
| 93 | } |
| 94 | |
| 95 | void* sk_buffer_write_int32(void* buffer, const int32_t values[], int count) |
| 96 | { |
| 97 | AssertBuffer32(buffer); |
| 98 | SkASSERT(count >= 0); |
| 99 | |
| 100 | memcpy((int32_t*)buffer, values, count * sizeof(int32_t)); |
| 101 | return (char*)buffer + count * sizeof(int32_t); |
| 102 | } |
| 103 | |
| 104 | const void* sk_buffer_read_int32(const void* buffer, int32_t* value) |
| 105 | { |
| 106 | AssertBuffer32(buffer); |
| 107 | if (value) |
| 108 | *value = *(const int32_t*)buffer; |
| 109 | return (const char*)buffer + sizeof(int32_t); |
| 110 | } |
| 111 | |
| 112 | const void* sk_buffer_read_int32(const void* buffer, int32_t values[], int count) |
| 113 | { |
| 114 | AssertBuffer32(buffer); |
| 115 | SkASSERT(count >= 0); |
| 116 | |
| 117 | if (values) |
| 118 | memcpy(values, (const int32_t*)buffer, count * sizeof(int32_t)); |
| 119 | return (const char*)buffer + count * sizeof(int32_t); |
| 120 | } |
| 121 | |
| 122 | void* sk_buffer_write_ptr(void* buffer, void* ptr) |
| 123 | { |
| 124 | AssertBuffer32(buffer); |
| 125 | *(void**)buffer = ptr; |
| 126 | return (char*)buffer + sizeof(void*); |
| 127 | } |
| 128 | |
| 129 | const void* sk_buffer_read_ptr(const void* buffer, void** ptr) |
| 130 | { |
| 131 | AssertBuffer32(buffer); |
| 132 | if (ptr) |
| 133 | *ptr = *(void**)buffer; |
| 134 | return (const char*)buffer + sizeof(void*); |
| 135 | } |
| 136 | |
| 137 | #endif |