76 lines
2.0 KiB
C++
Vendored
76 lines
2.0 KiB
C++
Vendored
/* Copyright (C) Teemu Suutari */
|
|
|
|
#include "LZBSDecompressor.hpp"
|
|
#include "InputStream.hpp"
|
|
#include "OutputStream.hpp"
|
|
#include "common/Common.hpp"
|
|
|
|
|
|
namespace ancient::internal
|
|
{
|
|
|
|
bool LZBSDecompressor::detectHeaderXPK(uint32_t hdr) noexcept
|
|
{
|
|
return hdr==FourCC("LZBS");
|
|
}
|
|
|
|
std::shared_ptr<XPKDecompressor> LZBSDecompressor::create(uint32_t hdr,uint32_t recursionLevel,const Buffer &packedData,std::shared_ptr<XPKDecompressor::State> &state,bool verify)
|
|
{
|
|
return std::make_shared<LZBSDecompressor>(hdr,recursionLevel,packedData,state,verify);
|
|
}
|
|
|
|
LZBSDecompressor::LZBSDecompressor(uint32_t hdr,uint32_t recursionLevel,const Buffer &packedData,std::shared_ptr<XPKDecompressor::State> &state,bool verify) :
|
|
XPKDecompressor(recursionLevel),
|
|
_packedData(packedData)
|
|
{
|
|
if (!detectHeaderXPK(hdr) || _packedData.size()<1) throw Decompressor::InvalidFormatError();
|
|
}
|
|
|
|
LZBSDecompressor::~LZBSDecompressor()
|
|
{
|
|
// nothing needed
|
|
}
|
|
|
|
const std::string &LZBSDecompressor::getSubName() const noexcept
|
|
{
|
|
static std::string name="XPK-LZBS: LZBS CyberYAFA compressor";
|
|
return name;
|
|
}
|
|
|
|
void LZBSDecompressor::decompressImpl(Buffer &rawData,const Buffer &previousData,bool verify)
|
|
{
|
|
ForwardInputStream inputStream(_packedData,1,_packedData.size());
|
|
MSBBitReader<ForwardInputStream> bitReader(inputStream);
|
|
auto readBits=[&](uint32_t count)->uint32_t
|
|
{
|
|
return rotateBits(bitReader.readBits8(count),count);
|
|
};
|
|
|
|
ForwardOutputStream outputStream(rawData,0,rawData.size());
|
|
|
|
uint32_t bits=0,maxBits=uint32_t(_packedData[0]);
|
|
while (!outputStream.eof())
|
|
{
|
|
if (!readBits(1))
|
|
{
|
|
outputStream.writeByte(readBits(8));
|
|
} else {
|
|
uint32_t count=readBits(8)+2;
|
|
if (count==2)
|
|
{
|
|
count=readBits(12);
|
|
if (!count) throw Decompressor::DecompressionError();
|
|
for (uint32_t i=0;i<count;i++)
|
|
outputStream.writeByte(readBits(8));
|
|
} else {
|
|
while (outputStream.getOffset()>=(1ULL<<bits) && bits<maxBits) bits++;
|
|
uint32_t distance=readBits(bits);
|
|
|
|
outputStream.copy(distance,count);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
}
|