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 10 #include <string.h> 11 12 //////////////////////////////////////////////////////////////////////////////////////// 13 14 void SkRBuffer::readNoSizeCheck(void* buffer, size_t size) 15 { 16 SkASSERT((fData != 0 && fStop == 0) || fPos + size <= fStop); 17 if (buffer) 18 memcpy(buffer, fPos, size); 19 fPos += size; 20 } 21 22 const void* SkRBuffer::skip(size_t size) 23 { 24 const void* result = fPos; 25 readNoSizeCheck(nullptr, size); 26 return result; 27 } 28 29 size_t SkRBuffer::skipToAlign4() 30 { 31 size_t pos = this->pos(); 32 size_t n = SkAlign4(pos) - pos; 33 fPos += n; 34 return n; 35 } 36 37 bool SkRBufferWithSizeCheck::read(void* buffer, size_t size) { 38 fError = fError || (size > static_cast<size_t>(fStop - fPos)); 39 if (!fError && (size > 0)) { 40 readNoSizeCheck(buffer, size); 41 } 42 return !fError; 43 } 44 45 void* SkWBuffer::skip(size_t size) 46 { 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 { 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 138
