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 "SkBuffer.h" 9 #include "SkMalloc.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
