SWORD_NAMESPACE_START
/******************************************************************************
* XzCompress Constructor - Initializes data for instance of XzCompress
*
*/
XzCompress::XzCompress() : SWCompress() {
level = 3;
// start with the estimated memory usage for our preset
memlimit = lzma_easy_decoder_memusage(level | LZMA_PRESET_EXTREME);
// and round up to a power of 2--
// bit twiddle hack to determine next greatest power of 2 from:
// http://graphics.stanford.edu/~seander/bithacks.html#RoundUpPowerOf2
memlimit--;
memlimit |= memlimit >> 1;
memlimit |= memlimit >> 2;
memlimit |= memlimit >> 4;
memlimit |= memlimit >> 8;
memlimit |= memlimit >> 16;
memlimit++;
// double that for safety's sake
memlimit <<= 1;
}
int LzmaConnectorReader::resetConnectorReader (void)
{
lzma_end (&_lzmaDecompStream);
resetDecompStream();
if (LZMA_OK != lzma_stream_decoder (&_lzmaDecompStream, lzma_easy_decoder_memusage (getCompressionLevel()), DECODER_FLAGS)) {
return -1;
}
return 0;
}
LzmaConnectorReader::LzmaConnectorReader (const CompressionSettings & compressionSettings, unsigned int ulInBufSize, unsigned int ulOutBufSize) :
ConnectorReader{compressionSettings}
{
if ((ulOutBufSize == 0) || (ulInBufSize == 0) ||
(nullptr == (_pOutputBuffer = new unsigned char[ulOutBufSize])) ||
(nullptr == (_pInputBuffer = new unsigned char[ulInBufSize]))) {
// throw a c++ exception here
}
_ulInBufSize = ulInBufSize;
_ulOutBufSize = ulOutBufSize;
resetDecompStream();
if (LZMA_OK != lzma_stream_decoder (&_lzmaDecompStream, lzma_easy_decoder_memusage (getCompressionLevel()), DECODER_FLAGS)) {
// throw a c++ exception here
}
}
void XzCompress::setLevel(int l) {
level = l;
// having changed the compression level, we need to adjust our memlimit accordingly,
// as in the constructor:
// start with the estimated memory usage for our preset
memlimit = lzma_easy_decoder_memusage(level | LZMA_PRESET_EXTREME);
// and round up to a power of 2--
// bit twiddle hack to determine next greatest power of 2 from:
// http://graphics.stanford.edu/~seander/bithacks.html#RoundUpPowerOf2
memlimit--;
memlimit |= memlimit >> 1;
memlimit |= memlimit >> 2;
memlimit |= memlimit >> 4;
memlimit |= memlimit >> 8;
memlimit |= memlimit >> 16;
memlimit++;
// double that for safety's sake
memlimit <<= 1;
};
Handle<Value> lzmaEasyDecoderMemusage(const Arguments& args) {
HandleScope scope;
Local<Integer> arg = Local<Integer>::Cast(args[0]);
return scope.Close(Uint64ToNumberMaxNull(lzma_easy_decoder_memusage(arg->Value())));
}