public static async Task <byte[]> BuildBlock(BadBlock badBlock)
{
if (badBlock.Data.Length % 4 != 0)
{
throw new ArgumentException("Bad block data must be dividable by 4", nameof(BadBlock.Data));
}
var structureSize = 6 * 4;
var maxDataSize = 512 - structureSize;
if (badBlock.Data.Length > maxDataSize)
{
throw new ArgumentException($"Bad block data is larger than max data size {maxDataSize}",
nameof(LoadSegBlock.Data));
}
var blockStream = new MemoryStream(badBlock.BlockBytes == null || badBlock.BlockBytes.Length == 0
? new byte[structureSize + badBlock.Data.Length]
: badBlock.BlockBytes);
var size = (structureSize + badBlock.Data.Length) / 4;
await blockStream.WriteAsciiString(BlockIdentifiers.BadBlock);
await blockStream.WriteLittleEndianUInt32((uint)size); // size
// skip checksum, calculated when block is built
blockStream.Seek(4, SeekOrigin.Current);
await blockStream.WriteLittleEndianUInt32(badBlock.HostId); // SCSI Target ID of host, not really used
await blockStream.WriteLittleEndianUInt32(badBlock.NextBadBlock); // next BadBlock block
// skip reserved
blockStream.Seek(4, SeekOrigin.Current);
// bad block data
await blockStream.WriteBytes(badBlock.Data);
// calculate and update checksum
var blockBytes = blockStream.ToArray();
badBlock.Checksum = await BlockHelper.UpdateChecksum(blockBytes, 8);
badBlock.BlockBytes = blockBytes;
return(blockBytes);
}
public static void ResetBadBlockPointers(BadBlock badBlock)
{
badBlock.NextBadBlock = 0;
}
