private static bool TryLocateMpqHeader(
Stream sourceStream,
#if NETCOREAPP3_0
[NotNullWhen(true)]
#endif
out MpqHeader?mpqHeader,
out long headerOffset)
{
sourceStream.Seek(0, SeekOrigin.Begin);
using (var reader = new BinaryReader(sourceStream, new UTF8Encoding(), true))
{
for (headerOffset = 0; headerOffset < sourceStream.Length - MpqHeader.Size; headerOffset += PreArchiveAlignBytes)
{
if (reader.ReadUInt32() == MpqHeader.MpqId)
{
sourceStream.Seek(-4, SeekOrigin.Current);
mpqHeader = MpqHeader.FromReader(reader);
mpqHeader.HeaderOffset = (uint)headerOffset;
return(true);
}
sourceStream.Seek(PreArchiveAlignBytes - 4, SeekOrigin.Current);
}
}
mpqHeader = null;
headerOffset = -1;
return(false);
}
private static long LocateMpqHeader(Stream sourceStream, out MpqHeader mpqHeader)
{
using (var reader = new BinaryReader(sourceStream, new UTF8Encoding(), true))
{
for (long i = 0; i < sourceStream.Length - MpqHeader.Size; i += PreArchiveAlignBytes)
{
sourceStream.Seek(i, SeekOrigin.Begin);
mpqHeader = MpqHeader.FromReader(reader);
if (mpqHeader?.SetHeaderOffset(i) ?? false)
{
return(i);
}
}
}
mpqHeader = null;
return(-1);
}
