michael@0: 
michael@0: /*
michael@0:  * Copyright 2006 The Android Open Source Project
michael@0:  *
michael@0:  * Use of this source code is governed by a BSD-style license that can be
michael@0:  * found in the LICENSE file.
michael@0:  */
michael@0: 
michael@0: 
michael@0: #include "SkBuffer.h"
michael@0: 
michael@0: ////////////////////////////////////////////////////////////////////////////////////////
michael@0: 
michael@0: void SkRBuffer::readNoSizeCheck(void* buffer, size_t size)
michael@0: {
michael@0:     SkASSERT((fData != 0 && fStop == 0) || fPos + size <= fStop);
michael@0:     if (buffer)
michael@0:         memcpy(buffer, fPos, size);
michael@0:     fPos += size;
michael@0: }
michael@0: 
michael@0: const void* SkRBuffer::skip(size_t size)
michael@0: {
michael@0:     const void* result = fPos;
michael@0:     readNoSizeCheck(NULL, size);
michael@0:     return result;
michael@0: }
michael@0: 
michael@0: size_t SkRBuffer::skipToAlign4()
michael@0: {
michael@0:     size_t pos = this->pos();
michael@0:     size_t n = SkAlign4(pos) - pos;
michael@0:     fPos += n;
michael@0:     return n;
michael@0: }
michael@0: 
michael@0: bool SkRBufferWithSizeCheck::read(void* buffer, size_t size) {
michael@0:     fError = fError || (fPos + size > fStop);
michael@0:     if (!fError && (size > 0)) {
michael@0:         readNoSizeCheck(buffer, size);
michael@0:     }
michael@0:     return !fError;
michael@0: }
michael@0: 
michael@0: void* SkWBuffer::skip(size_t size)
michael@0: {
michael@0:     void* result = fPos;
michael@0:     writeNoSizeCheck(NULL, size);
michael@0:     return fData == NULL ? NULL : result;
michael@0: }
michael@0: 
michael@0: void SkWBuffer::writeNoSizeCheck(const void* buffer, size_t size)
michael@0: {
michael@0:     SkASSERT(fData == 0 || fStop == 0 || fPos + size <= fStop);
michael@0:     if (fData && buffer)
michael@0:         memcpy(fPos, buffer, size);
michael@0:     fPos += size;
michael@0: }
michael@0: 
michael@0: size_t SkWBuffer::padToAlign4()
michael@0: {
michael@0:     size_t pos = this->pos();
michael@0:     size_t n = SkAlign4(pos) - pos;
michael@0: 
michael@0:     if (n && fData)
michael@0:     {
michael@0:         char* p = fPos;
michael@0:         char* stop = p + n;
michael@0:         do {
michael@0:             *p++ = 0;
michael@0:         } while (p < stop);
michael@0:     }
michael@0:     fPos += n;
michael@0:     return n;
michael@0: }
michael@0: 
michael@0: #if 0
michael@0: #ifdef SK_DEBUG
michael@0:     static void AssertBuffer32(const void* buffer)
michael@0:     {
michael@0:         SkASSERT(buffer);
michael@0:         SkASSERT(((size_t)buffer & 3) == 0);
michael@0:     }
michael@0: #else
michael@0:     #define AssertBuffer32(buffer)
michael@0: #endif
michael@0: 
michael@0: void* sk_buffer_write_int32(void* buffer, int32_t value)
michael@0: {
michael@0:     AssertBuffer32(buffer);
michael@0:     *(int32_t*)buffer = value;
michael@0:     return (char*)buffer + sizeof(int32_t);
michael@0: }
michael@0: 
michael@0: void* sk_buffer_write_int32(void* buffer, const int32_t values[], int count)
michael@0: {
michael@0:     AssertBuffer32(buffer);
michael@0:     SkASSERT(count >= 0);
michael@0: 
michael@0:     memcpy((int32_t*)buffer, values, count * sizeof(int32_t));
michael@0:     return (char*)buffer + count * sizeof(int32_t);
michael@0: }
michael@0: 
michael@0: const void* sk_buffer_read_int32(const void* buffer, int32_t* value)
michael@0: {
michael@0:     AssertBuffer32(buffer);
michael@0:     if (value)
michael@0:         *value = *(const int32_t*)buffer;
michael@0:     return (const char*)buffer + sizeof(int32_t);
michael@0: }
michael@0: 
michael@0: const void* sk_buffer_read_int32(const void* buffer, int32_t values[], int count)
michael@0: {
michael@0:     AssertBuffer32(buffer);
michael@0:     SkASSERT(count >= 0);
michael@0: 
michael@0:     if (values)
michael@0:         memcpy(values, (const int32_t*)buffer, count * sizeof(int32_t));
michael@0:     return (const char*)buffer + count * sizeof(int32_t);
michael@0: }
michael@0: 
michael@0: void* sk_buffer_write_ptr(void* buffer, void* ptr)
michael@0: {
michael@0:     AssertBuffer32(buffer);
michael@0:     *(void**)buffer = ptr;
michael@0:     return (char*)buffer + sizeof(void*);
michael@0: }
michael@0: 
michael@0: const void* sk_buffer_read_ptr(const void* buffer, void** ptr)
michael@0: {
michael@0:     AssertBuffer32(buffer);
michael@0:     if (ptr)
michael@0:         *ptr = *(void**)buffer;
michael@0:     return (const char*)buffer + sizeof(void*);
michael@0: }
michael@0: 
michael@0: #endif