PrismLauncher/logic/GZip.cpp

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#include "GZip.h"
#include <zlib.h>
#include <QByteArray>
// HACK: workaround for terrible macro crap on Windows
int wrap_inflate (z_streamp strm, int flush)
{
return inflate(strm, flush);
}
#ifdef inflate
#undef inflate
#endif
bool GZip::inflate(const QByteArray &compressedBytes, QByteArray &uncompressedBytes)
{
if (compressedBytes.size() == 0)
{
uncompressedBytes = compressedBytes;
return true;
}
unsigned uncompLength = compressedBytes.size();
unsigned half_length = compressedBytes.size() / 2;
uncompressedBytes.clear();
uncompressedBytes.resize(uncompLength);
z_stream strm;
strm.next_in = (Bytef *)compressedBytes.data();
strm.avail_in = compressedBytes.size();
strm.total_out = 0;
strm.zalloc = Z_NULL;
strm.zfree = Z_NULL;
bool done = false;
if (inflateInit2(&strm, (16 + MAX_WBITS)) != Z_OK)
{
return false;
}
while (!done)
{
// If our output buffer is too small
if (strm.total_out >= uncompLength)
{
uncompressedBytes.resize(uncompLength + half_length);
uncompLength += half_length;
}
strm.next_out = (Bytef *)(uncompressedBytes.data() + strm.total_out);
strm.avail_out = uncompLength - strm.total_out;
// Inflate another chunk.
int err = wrap_inflate(&strm, Z_SYNC_FLUSH);
if (err == Z_STREAM_END)
done = true;
else if (err != Z_OK)
{
break;
}
}
if (inflateEnd(&strm) != Z_OK)
{
return false;
}
uncompressedBytes.resize(strm.total_out);
return true;
}