| 1 | /* |
|---|---|
| 2 | * Copyright 2006 The Android Open Source Project |
| 3 | * |
| 4 | * Use of this source code is governed by a BSD-style license that can be |
| 5 | * found in the LICENSE file. |
| 6 | */ |
| 7 | |
| 8 | #include "include/private/SkMalloc.h" |
| 9 | #include "src/core/SkBuffer.h" |
| 10 | #include <string.h> |
| 11 | |
| 12 | /////////////////////////////////////////////////////////////////////////////////////////////////// |
| 13 | |
| 14 | const void* SkRBuffer::skip(size_t size) { |
| 15 | if (fValid && size <= this->available()) { |
| 16 | const void* pos = fPos; |
| 17 | fPos += size; |
| 18 | return pos; |
| 19 | } |
| 20 | fValid = false; |
| 21 | return nullptr; |
| 22 | } |
| 23 | |
| 24 | bool SkRBuffer::read(void* buffer, size_t size) { |
| 25 | if (const void* src = this->skip(size)) { |
| 26 | sk_careful_memcpy(buffer, src, size); |
| 27 | return true; |
| 28 | } |
| 29 | return false; |
| 30 | } |
| 31 | |
| 32 | bool SkRBuffer::skipToAlign4() { |
| 33 | intptr_t pos = reinterpret_cast<intptr_t>(fPos); |
| 34 | size_t n = SkAlign4(pos) - pos; |
| 35 | if (fValid && n <= this->available()) { |
| 36 | fPos += n; |
| 37 | return true; |
| 38 | } else { |
| 39 | fValid = false; |
| 40 | return false; |
| 41 | } |
| 42 | } |
| 43 | |
| 44 | /////////////////////////////////////////////////////////////////////////////////////////////////// |
| 45 | |
| 46 | void* SkWBuffer::skip(size_t size) { |
| 47 | void* result = fPos; |
| 48 | writeNoSizeCheck(nullptr, size); |
| 49 | return fData == nullptr ? nullptr : result; |
| 50 | } |
| 51 | |
| 52 | void SkWBuffer::writeNoSizeCheck(const void* buffer, size_t size) { |
| 53 | SkASSERT(fData == nullptr || fStop == nullptr || fPos + size <= fStop); |
| 54 | if (fData && buffer) { |
| 55 | sk_careful_memcpy(fPos, buffer, size); |
| 56 | } |
| 57 | fPos += size; |
| 58 | } |
| 59 | |
| 60 | size_t SkWBuffer::padToAlign4() { |
| 61 | size_t pos = this->pos(); |
| 62 | size_t n = SkAlign4(pos) - pos; |
| 63 | |
| 64 | if (n && fData) |
| 65 | { |
| 66 | char* p = fPos; |
| 67 | char* stop = p + n; |
| 68 | do { |
| 69 | *p++ = 0; |
| 70 | } while (p < stop); |
| 71 | } |
| 72 | fPos += n; |
| 73 | return n; |
| 74 | } |
| 75 | |
| 76 | #if 0 |
| 77 | #ifdef SK_DEBUG |
| 78 | static void AssertBuffer32(const void* buffer) |
| 79 | { |
| 80 | SkASSERT(buffer); |
| 81 | SkASSERT(((size_t)buffer & 3) == 0); |
| 82 | } |
| 83 | #else |
| 84 | #define AssertBuffer32(buffer) |
| 85 | #endif |
| 86 | |
| 87 | #endif |
| 88 |