cocos-engine/native/cocos/core/DataView.cpp

/****************************************************************************
 Copyright (c) 2021 Xiamen Yaji Software Co., Ltd.
 
 http://www.cocos.com
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated engine source code (the "Software"), a limited,
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 used for developing games. You are not granted to publish, distribute,
 sublicense, and/or sell copies of Cocos Creator.
 
 The software or tools in this License Agreement are licensed, not sold.
 Xiamen Yaji Software Co., Ltd. reserves all rights not expressly granted to you.
 
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 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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#include "core/DataView.h"

namespace cc {

#include "base/Macros.h"
#include "core/ArrayBuffer.h"

ccstd::unordered_map<ccstd::string, DataView::ReaderVariant> DataView::intReaderMap{
    {"getUint8", &DataView::getUint8},
    {"getUint16", &DataView::getUint16},
    {"getUint32", &DataView::getUint32},
    {"getInt8", &DataView::getInt8},
    {"getInt16", &DataView::getInt16},
    {"getInt32", &DataView::getInt32},
};

ccstd::unordered_map<ccstd::string, DataView::IntWritter> DataView::intWritterMap{
    {"setUint8", reinterpret_cast<DataView::IntWritter>(&DataView::setUint8)},
    {"setUint16", reinterpret_cast<DataView::IntWritter>(&DataView::setUint16)},
    {"setUint32", reinterpret_cast<DataView::IntWritter>(&DataView::setUint32)},
    {"setInt8", reinterpret_cast<DataView::IntWritter>(&DataView::setInt8)},
    {"setInt16", reinterpret_cast<DataView::IntWritter>(&DataView::setInt16)},
    {"setInt32", reinterpret_cast<DataView::IntWritter>(&DataView::setInt32)},
};

int32_t DataView::readInt(ReaderVariant &readerVariant, uint32_t offset) {
    return ccstd::visit([offset, this](auto &reader) {
        return static_cast<int32_t>((this->*reader)(offset));
    },
                        readerVariant);
}

DataView::DataView(ArrayBuffer *buffer) : DataView(buffer, 0) {}

DataView::DataView(ArrayBuffer *buffer, uint32_t byteOffset)
: DataView(buffer, byteOffset, buffer ? (buffer->byteLength() - byteOffset) : 0) {}

DataView::DataView(ArrayBuffer *buffer, uint32_t byteOffset, uint32_t byteLength) {
    assign(buffer, byteOffset, byteLength);
}

void DataView::assign(ArrayBuffer *buffer) {
    assign(buffer, 0);
}

void DataView::assign(ArrayBuffer *buffer, uint32_t byteOffset) {
    assign(buffer, byteOffset, buffer ? buffer->byteLength() : 0);
}

void DataView::assign(ArrayBuffer *buffer, uint32_t byteOffset, uint32_t byteLength) {
    CC_ASSERT(buffer != nullptr);
    CC_ASSERT(byteLength > 0);
    _buffer = buffer;
    _byteOffset = byteOffset;
    _byteEndPos = byteLength + byteOffset;
    CC_ASSERT(_byteEndPos <= buffer->_byteLength);

    _data = buffer->_data;
}

uint8_t DataView::getUint8(uint32_t offset) const {
    offset += _byteOffset;
    CC_ASSERT(offset < _byteEndPos);

    return _data[offset];
}

uint16_t DataView::getUint16(uint32_t offset) const {
    offset += _byteOffset;
    CC_ASSERT(offset < (_byteEndPos - 1));

    return *reinterpret_cast<uint16_t *>(_data + offset);
}

uint32_t DataView::getUint32(uint32_t offset) const {
    offset += _byteOffset;
    CC_ASSERT(offset < (_byteEndPos - 3));

    return *reinterpret_cast<uint32_t *>(_data + offset);
}

int8_t DataView::getInt8(uint32_t offset) const {
    offset += _byteOffset;
    CC_ASSERT(offset < _byteEndPos);

    return static_cast<int8_t>(_data[offset]);
}

int16_t DataView::getInt16(uint32_t offset) const {
    offset += _byteOffset;
    CC_ASSERT(offset < (_byteEndPos - 1));

    return *reinterpret_cast<int16_t *>(_data + offset);
}

int32_t DataView::getInt32(uint32_t offset) const {
    offset += _byteOffset;
    CC_ASSERT(offset < (_byteEndPos - 3));

    return *reinterpret_cast<int32_t *>(_data + offset);
}

float DataView::getFloat32(uint32_t offset) const {
    offset += _byteOffset;
    CC_ASSERT(offset < (_byteEndPos - 3));

    return *reinterpret_cast<float *>(_data + offset);
}

void DataView::setUint8(uint32_t offset, uint8_t value) {
    offset += _byteOffset;
    CC_ASSERT(offset < _byteEndPos);

    _data[offset] = value;
}

void DataView::setUint16(uint32_t offset, uint16_t value) {
    offset += _byteOffset;
    CC_ASSERT(offset < _byteEndPos - 1);

    *reinterpret_cast<uint16_t *>(_data + offset) = value;
}

void DataView::setUint32(uint32_t offset, uint32_t value) {
    offset += _byteOffset;
    CC_ASSERT(offset < _byteEndPos - 3);

    *reinterpret_cast<uint32_t *>(_data + offset) = value;
}

void DataView::setInt8(uint32_t offset, int8_t value) {
    offset += _byteOffset;
    CC_ASSERT(offset < _byteEndPos);

    *reinterpret_cast<int8_t *>(_data + offset) = value;
}

void DataView::setInt16(uint32_t offset, int16_t value) {
    offset += _byteOffset;
    CC_ASSERT(offset < _byteEndPos - 1);

    *reinterpret_cast<int16_t *>(_data + offset) = value;
}

void DataView::setInt32(uint32_t offset, int32_t value) {
    offset += _byteOffset;
    CC_ASSERT(offset < _byteEndPos - 3);

    *reinterpret_cast<int32_t *>(_data + offset) = value;
}

void DataView::setFloat32(uint32_t offset, float value) {
    offset += _byteOffset;
    CC_ASSERT(offset < _byteEndPos - 3);

    *(reinterpret_cast<float *>(_data + offset)) = value;
}

} // namespace cc