/**
*\brief does data compression
*
*will be called from a thread.
*should not try to allocate memory.
*Need not be reentrant itself as it will only run once at a time.
*
*\param input input buffer (holding blk_sz bytes)
*\param outbuf output buffer large enough for worst case compression
*\returns number of bytes written to outbuf
*/
size_t compress(char *input, char *outbuf)
{
uint32_t preset = COMPRESSION_LEVEL | (COMPRESSION_EXTREME ? LZMA_PRESET_EXTREME : 0);
int r;
size_t out_pos=0;
lzma_check check = INTEGRITY_CHECK;
r=lzma_raw_buffer_encode(lz_flt,&lzma_alc,(uint8_t*)input,blk_sz,(uint8_t*)outbuf,&out_pos,bound);
// r=lzma_easy_buffer_encode(preset,check,&lzma_alc,(uint8_t*)input,blk_sz,(uint8_t*)outbuf,&out_pos,bound);
assert(r == LZMA_OK);
return out_pos;
}
size_t fa_compress_block(fa_compression_t compression, void* out, size_t outSize, const void* in, size_t inSize)
{
switch (compression)
{
default: return inSize;
case FA_COMPRESSION_FASTLZ:
{
if (inSize < 16)
{
return inSize;
}
return fastlz_compress_level(2, in, inSize, out);
}
break;
#if defined(FA_ZLIB_ENABLE)
case FA_COMPRESSION_DEFLATE:
{
uLongf destLen = outSize;
if (outSize < compressBound(inSize))
{
return inSize;
}
if (compress2(out, &destLen, in, inSize, Z_DEFAULT_COMPRESSION) != Z_OK)
{
return inSize;
}
return destLen;
}
break;
#endif
#if defined(FA_LZMA_ENABLE)
case FA_COMPRESSION_LZMA2:
{
size_t outPos = 0;
lzma_filter filters[2];
lzma_options_lzma options;
if (lzma_lzma_preset(&options, 6))
{
return inSize;
}
filters[0].id = LZMA_FILTER_LZMA2;
filters[0].options = &options;
filters[1].id = LZMA_VLI_UNKNOWN;
lzma_ret ret = lzma_raw_buffer_encode(filters, NULL, in, inSize, out, &outPos, outSize);
if (ret != LZMA_OK)
{
return inSize;
}
return outPos;
}
break;
#endif
}
}
