private BruteForceCrcResult results(headerCrc matchHdr, regionCrc matchRgn, uint updateCrc, uint matchCrc, bool isRedump)
{
if (matchHdr == null && matchRgn == null)
{
return new BruteForceCrcResult()
{
Region = _origRegion
}
}
;
//create the header
byte[] header = (matchHdr ?? matchRgn.Header).Data;
bool regionDataChanged = false;
if (matchRgn != null)
{
MemorySection ms = new MemorySection(header);
regionDataChanged = !matchRgn.Region.Equals(_origRegionData);
ms.WriteUInt32B(0x4e000, (uint)matchRgn.Region);
ms.Write(0x4e010, matchRgn.RegionData);
}
uint headerCrc = Crc.Compute(header);
if (headerCrc == _origHeaderCrc)
{
header = null;
}
return(new BruteForceCrcResult()
{
MatchedCrc = matchCrc,
MatchedCrcIsRedump = isRedump,
HeaderChanged = header != null && _origHeaderCrc != headerCrc,
Header = header,
HeaderCrc = Crc.Compute(header),
UpdateChanged = updateCrc != 0 && _origUpdateCrc != updateCrc,
UpdateCrc = updateCrc,
Region = matchRgn?.Region ?? _origRegion,
OriginalRegion = _origRegion,
RegionData = matchRgn?.RegionData,
RegionChanged = matchRgn != null && (regionDataChanged || matchRgn.Region != _origRegion)
});
}
}
public BruteForceCrcResult Match(CrcItem[] crcs)
{
//reduce crcs to 3 - header, update, postUpdate
_origHeaderCrc = crcs[0].Value;
_origUpdateCrc = crcs[1].Value;
long updateSize = (crcs.Length > 2 ? crcs[2].Offset - crcs[1].Offset : 0);
uint postUpdateCrc = (crcs.Length > 2 ? crcs[2].Value : 0);
long postUpdateSize = (crcs.Length > 2 ? crcs[2].Length : 0);
for (int x = 3; x < crcs.Length; x++)
{
postUpdateCrc = ~Crc.Combine(~postUpdateCrc, ~crcs[x].Value, crcs[x].Length);
postUpdateSize += crcs[x].Length;
}
//DateTime dt = DateTime.Now;
//quick test without region brute force (which can take a while)
headerCrc headerMatch = null;
regionCrc regionMatch = null;
uint matchCrc = 0;
uint matchUpdateCrc = 0;
uint u = _updateCrcs.AsParallel().FirstOrDefault(uCrc =>
{
headerCrc m = _hdrs.AsParallel().FirstOrDefault(hdr =>
{
uint crc = ~Crc.Combine(Crc.Combine(~hdr.Crc, ~uCrc, updateSize), ~postUpdateCrc, postUpdateSize);
if (_checkCrcs.ContainsKey(crc))
{
matchCrc = crc;
headerMatch = hdr;
matchUpdateCrc = uCrc;
}
return(matchCrc != 0);
});
return(matchCrc != 0);
});
//Trace.WriteLine(string.Format("Crc Update Combos: {0} - Took: {1}", _updateCrcs.Length.ToString(), (DateTime.Now - dt).TotalMilliseconds.ToString()));
if (headerMatch == null)
{
//dt = DateTime.Now;
//region brute force tests - FirstOrDefault is used and the results are discarded as nesting them causes threading issues
uint u2 = _updateCrcs.AsParallel().FirstOrDefault(uCrc =>
{
//combine the update crc with the post update crc
uint updDataCrc = ~Crc.Combine(~uCrc, ~postUpdateCrc, postUpdateSize);
long updDataSize = updateSize + postUpdateSize;
//compare the header/region with the update and post update combines crc
regionCrc m = _regionData.AsParallel().FirstOrDefault(rgn =>
{
uint crc = ~Crc.Combine(~rgn.Crc, ~updDataCrc, updDataSize);
if (_checkCrcs.ContainsKey(crc))
{
matchCrc = crc;
regionMatch = rgn;
matchUpdateCrc = uCrc;
}
return(matchCrc != 0);
});
return(matchCrc != 0);
});
//Trace.WriteLine(string.Format("Crc Header / Update Combos: {0} - Took: {1}", (_updateCrcs.Length * _regionData.Count).ToString(), (DateTime.Now - dt).TotalMilliseconds.ToString()));
}
return(results(headerMatch, regionMatch, matchUpdateCrc, matchCrc, matchCrc == 0 ? false : _checkCrcs[matchCrc]));
}
