/// <summary>
/// Create a new data block instance from a byte array from data found within the container file.
/// </summary>
/// <param name="fs">The FileStream instance to use.</param>
/// <param name="blockSize">The block size, in bytes.</param>
/// <param name="ba">The byte array containing the full block.</param>
/// <param name="logging">Instance of LoggingModule to use for logging events.</param>
/// <returns>A populated DataBlock object.</returns>
public static DataBlock FromBytes(FileStream fs, int blockSize, byte[] ba, LoggingModule logging)
{
try
{
if (ba == null || ba.Length < 1)
{
throw new ArgumentNullException(nameof(ba));
}
if (ba.Length < 64)
{
throw new ArgumentException("Byte array has length less than 64");
}
if (blockSize < 4096)
{
throw new ArgumentOutOfRangeException("Block size must be greater than or equal to 4096");
}
if (blockSize % 4096 != 0)
{
throw new ArgumentOutOfRangeException("Block size must be evenly divisible by 4096");
}
if (fs == null)
{
throw new ArgumentNullException(nameof(fs));
}
if (logging != null)
{
logging.Log(LoggingModule.Severity.Debug, "FromBytes converting " + ba.Length + " bytes to DataBlock");
}
DataBlock ret = new DataBlock(fs, blockSize, null, logging);
ret.Signature = new byte[4];
ret.Logging = logging;
ret.Filestream = fs;
byte[] temp;
Buffer.BlockCopy(ba, 0, ret.Signature, 0, 4);
temp = new byte[4];
Buffer.BlockCopy(ba, 8, temp, 0, 4);
ret.Signature = temp;
temp = new byte[8];
Buffer.BlockCopy(ba, 4, temp, 0, 8);
ret.ParentBlock = BitConverter.ToInt64(temp, 0);
temp = new byte[8];
Buffer.BlockCopy(ba, 12, temp, 0, 8);
ret.ChildBlock = BitConverter.ToInt32(temp, 0);
temp = new byte[4];
Buffer.BlockCopy(ba, 20, temp, 0, 4);
ret.DataLength = BitConverter.ToInt32(temp, 0);
if (logging != null)
{
logging.Log(LoggingModule.Severity.Debug, "FromBytes reading data " + ret.DataLength + " bytes from position 64");
}
temp = new byte[ret.DataLength];
Buffer.BlockCopy(ba, 64, temp, 0, ret.DataLength);
ret.Data = temp;
return(ret);
}
catch (Exception e)
{
if (logging != null)
{
logging.LogException("DataBlock", "FromBytes", e);
}
else
{
LoggingModule.ConsoleException("DataBlock", "FromBytes", e);
}
throw;
}
}
