62 lines
1.9 KiB
C++
62 lines
1.9 KiB
C++
#include "CCDataFormat.h"
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#include <cstring>
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#include <stdexcept>
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#include "zip.h"
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std::vector<char> CTL::DataFormat::CompressData(const std::vector<char> &input) {
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if (input.size() < COMPRESSION_THRESHOLD) {
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return input;
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}
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// 计算压缩后最大长度
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uLong maxCompressedSize = compressBound(input.size());
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std::vector<char> compressed(maxCompressedSize + sizeof(uLong)); // +4字节存储原始长度
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// 在头部存储原始数据长度（4字节）
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auto originalSize = static_cast<uLong>(input.size());
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memcpy(compressed.data(), &originalSize, sizeof(uLong));
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// 执行压缩
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int result = compress2(
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reinterpret_cast<Bytef*>(compressed.data()) + sizeof(uLong), // 偏移4字节
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&maxCompressedSize,
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reinterpret_cast<const Bytef*>(input.data()),
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input.size(),
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Z_BEST_COMPRESSION // 最高压缩率
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);
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if (result != Z_OK) {
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throw std::runtime_error("Compression failed");
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}
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// 调整vector大小为实际压缩后长度 + 4字节头
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compressed.resize(maxCompressedSize + sizeof(uLong));
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return compressed;
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}
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std::vector<char> CTL::DataFormat::DecompressData(const std::vector<char> &compressed) {
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if (compressed.size() < sizeof(uLong)) {
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throw std::runtime_error("Invalid compressed data");
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}
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// 从头部提取原始数据长度
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uLong originalSize;
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memcpy(&originalSize, compressed.data(), sizeof(uLong));
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std::vector<char> output(originalSize);
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uLong decompressedSize = originalSize;
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int result = uncompress(
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reinterpret_cast<Bytef*>(output.data()),
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&decompressedSize,
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reinterpret_cast<const Bytef*>(compressed.data()) + sizeof(uLong), // 跳过4字节头
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compressed.size() - sizeof(uLong)
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);
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if (result != Z_OK || decompressedSize != originalSize) {
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throw std::runtime_error("Decompression failed");
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}
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return output;
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}
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