public static bool TryGetMbrInfo(DiskImage hdd, out MbrPartitioningInfo info)
{
info = default;
Debug.Assert(Unsafe.SizeOf <MbrHeader>() == MBR_SIZE);
var headerBytes = hdd.ReadBytes(0, MBR_SIZE);
MbrHeader header = MemoryMarshal.Cast <byte, MbrHeader>(new Span <byte>(headerBytes))[0];
if (header.BootSig != MbrHeader.MbrMagic)
{
return(false);
}
bool hasGpt = false;
for (int i = 0; i < 4; i++)
{
var part = header.GetPartition(i);
hasGpt |= part.Type == MbrPartitionType.GptProtective;
}
//MBR paritioned disks often contain boot loaders in non-paritioned space.
//So to be safe copy all the data.
List <FileExtent> partitions = new List <FileExtent>()
{
new FileExtent(MBR_SIZE, hdd.Length - MBR_SIZE),
};
info = new MbrPartitioningInfo(headerBytes, partitions, hasGpt);
return(true);
}
public async Task WriteParitionTableAsync(Stream diskStream, long diskLength)
{
MbrHeader header = MemoryMarshal.Cast <byte, MbrHeader>(new ReadOnlySpan <byte>(mHeader))[0];
fixupPartitionEntry(ref header.Partition1, diskLength);
fixupPartitionEntry(ref header.Partition2, diskLength);
fixupPartitionEntry(ref header.Partition3, diskLength);
fixupPartitionEntry(ref header.Partition4, diskLength);
var headerBytes = new byte[MBR_SIZE];
MemoryMarshal.Write(new Span <byte>(headerBytes), ref header);
//var headerBytes = MemoryMarshal.Write
diskStream.Seek(0, SeekOrigin.Begin);
await diskStream.WriteAsync(headerBytes, 0, headerBytes.Length);
await diskStream.FlushAsync();
}
