public LogicalRecordSegment ReadLogicalRecordSegment(Stream dlisStream)
{
if (dlisStream == null)
{
return(null);
}
if (dlisStream.IsAtEndOfStream())
{
return(null);
}
var header = _logicalRecordSegmentHeaderBusiness.ReadLogicalRecordSegmentHeader(dlisStream);
if (header == null)
{
return(null);
}
var bodySize = header.LogicalRecordSegmentLength - 4;
LogicalRecordSegmentEncryptionPacket encryptionPacket = null;
if (header.EncryptionPacket)
{
encryptionPacket = _logicalRecordSegmentEncryptionPacketBusiness.ReadLogicalRecordSegmentEncryptionPacket(dlisStream);
if (encryptionPacket == null)
{
return(null);
}
bodySize -= encryptionPacket.Size;
}
LogicalRecordSegmentTrailer trailer = null;
var trailerSize = 0;
if (header.HasTrailer())
{
dlisStream.Seek(bodySize, SeekOrigin.Current);
trailer = _logicalRecordSegmentTrailerBusiness.ReadLogicalRecordSegmentTrailer(dlisStream, header);
if (trailer == null)
{
return(null);
}
trailerSize = header.TrailerSize(trailer);
bodySize -= trailerSize;
dlisStream.Seek(-(bodySize + trailerSize), SeekOrigin.Current);
}
var body = dlisStream.ReadBytes(bodySize);
dlisStream.Seek(trailerSize, SeekOrigin.Current);
return(new LogicalRecordSegment
{
Header = header,
EncryptionPacket = encryptionPacket,
Body = body,
Trailer = trailer
});
}
public static int TrailerSize(this LogicalRecordSegmentHeader header, LogicalRecordSegmentTrailer trailer)
{
if (header == null)
{
return(0);
}
if (trailer == null)
{
return(0);
}
var size = 0;
if (header.TrailingLength)
{
size += 2;
}
if (header.Checksum)
{
size += 2;
}
if (header.Padding)
{
size += trailer.PadCount;
}
return(size);
}
public LogicalRecordSegmentTrailer ReadLogicalRecordSegmentTrailer(Stream dlisStream, LogicalRecordSegmentHeader header)
{
if (dlisStream == null)
{
return(null);
}
if (dlisStream.IsAtBeginningOfStream())
{
return(null);
}
if (header == null)
{
return(null);
}
if (!header.HasTrailer())
{
return(null);
}
var trailer = new LogicalRecordSegmentTrailer();
if (header.TrailingLength)
{
dlisStream.Seek(-2, SeekOrigin.Current);
}
if (header.Checksum)
{
dlisStream.Seek(-2, SeekOrigin.Current);
}
if (header.Padding)
{
dlisStream.Seek(-1, SeekOrigin.Current);
trailer.PadCount = _ushortReader.ReadUSHORT(dlisStream);
dlisStream.Seek(-trailer.PadCount, SeekOrigin.Current);
trailer.Padding = dlisStream.ReadBytes(trailer.PadCount);
}
if (header.Checksum)
{
trailer.Checksum = _unormReader.ReadUNORM(dlisStream);
}
if (header.TrailingLength)
{
trailer.TrailingLength = _unormReader.ReadUNORM(dlisStream);
}
return(trailer);
}
public void LogicalRecordSegmentBusiness_ReadLogicalRecordSegment_Pass()
{
var dlisData = new byte[]
{
0x00, 0x14, 0xFF, 0x00,
0x00, 0x06, 0x00, 0x01,
0x00, 0x00, 0x0B, 0x0C,
0x0D, 0x0E, 0x00, 0x02,
0x00, 0x01, 0x00, 0x14
};
var dlisStream = new MemoryStream(dlisData);
var header = new LogicalRecordSegmentHeader
{
LogicalRecordSegmentLength = 20,
LogicalRecordSegmentAttributes = 0xFF
};
var encryptionPacket = new LogicalRecordSegmentEncryptionPacket
{
Size = 6,
CompanyCode = 1,
EncryptionInfo = new byte[] { 0, 0 }
};
var trailer = new LogicalRecordSegmentTrailer
{
PadCount = 2,
Padding = new byte[] { 0, 2 },
Checksum = 1,
TrailingLength = 20
};
_logicalRecordSegmentHeaderBusiness.Setup(x => x.ReadLogicalRecordSegmentHeader(dlisStream)).Returns(header);
_logicalRecordSegmentEncryptionPacketBusiness.Setup(x => x.ReadLogicalRecordSegmentEncryptionPacket(dlisStream)).Returns(encryptionPacket);
_logicalRecordSegmentTrailerBusiness.Setup(x => x.ReadLogicalRecordSegmentTrailer(dlisStream, header)).Returns(trailer);
/* simulate the mocked objects reading the header and encryption packet by seeking 10 bytes */
dlisStream.Seek(10, SeekOrigin.Begin);
var result = _logicalRecordSegmentBusiness.ReadLogicalRecordSegment(dlisStream);
Assert.AreEqual(0x0B, ((byte[])result.Body)[0]);
Assert.AreEqual(0x0C, ((byte[])result.Body)[1]);
Assert.AreEqual(0x0D, ((byte[])result.Body)[2]);
Assert.AreEqual(0x0E, ((byte[])result.Body)[3]);
}
