public static Frame ReadFromStream(Stream inputStream)
{
byte[] frameBytes = new byte[BW_HEADER_LENGTH];
string[] authorizationTokens;
try
{
inputStream.Read(frameBytes, 0, BW_HEADER_LENGTH);
string frameHeader = Encoding.UTF8.GetString(frameBytes);
authorizationTokens = Regex.Split(frameHeader.Trim(), " ");
}
catch (IOException ex)
{
throw new IOException("The Header is corrupted.\n", ex);
}
if (authorizationTokens.Length != 3)
{
throw new CorruptedFrameException("Frame header must have a length of 3.\nCurrent length: " + authorizationTokens.Length);
}
Command command = CommandUtils.GetCommand(authorizationTokens[0]);
int frameLength;
try
{
frameLength = int.Parse(authorizationTokens[1]);
}
catch (FormatException ex)
{
throw new CorruptedFrameException("The length of the Frame Header is invalid.\n", ex);
}
int sequenceNumber;
try
{
sequenceNumber = int.Parse(authorizationTokens[2]);
}
catch (FormatException ex)
{
throw new CorruptedFrameException("The sequence number is invalid.\n", ex);
}
List <VSKeyPair> vsKeyPairs = new List <VSKeyPair>();
List <PayloadObject> payloadObjects = new List <PayloadObject>();
List <RoutingObject> routingObjects = new List <RoutingObject>();
string currentLine;
while (!(currentLine = ReadLine(inputStream)).Equals("end"))
{
string[] tokens = Regex.Split(currentLine, " ");
if (tokens.Length != 3)
{
throw new CorruptedFrameException("The Header does not contain three fields but " + tokens.Length + ".");
}
int length;
try
{
length = int.Parse(tokens[2]);
if (length < 0)
{
throw new CorruptedFrameException("The length of the Header is negative: " + currentLine);
}
}
catch (FormatException ex)
{
throw new CorruptedFrameException("The length of the Header is corrupted: " + currentLine + "\n", ex);
}
switch (tokens[0])
{
case "kv":
string key = tokens[1];
byte[] vkBody = new byte[length];
inputStream.Read(vkBody, 0, length);
VSKeyPair vsKeyPair = new VSKeyPair(key, vkBody);
vsKeyPairs.Add(vsKeyPair);
inputStream.ReadByte();
break;
case "ro":
int routingNumber;
try
{
routingNumber = int.Parse(tokens[1]);
if (routingNumber < 0 || routingNumber > 255)
{
throw new CorruptedFrameException("The Routing number must be: 0 < routingNumber > 255: " + currentLine);
}
}
catch (FormatException ex)
{
throw new CorruptedFrameException("The Routing number must be: 0 < routingNumber > 255: " + currentLine);
}
byte[] routingBody = new byte[length];
inputStream.Read(routingBody, 0, length);
RoutingObject routingObject = new RoutingObject(routingNumber, routingBody);
routingObjects.Add(routingObject);
inputStream.ReadByte();
break;
case "po":
PayloadType payloadType;
try
{
payloadType = PayloadUtils.FromString(tokens[1]);
}
catch (ArgumentException ex)
{
throw new CorruptedFrameException("The Payload type is invalid: " + currentLine + "\n", ex);
}
byte[] payloadBody = new byte[length];
inputStream.Read(payloadBody, 0, length);
PayloadObject payloadObject = new PayloadObject(payloadType, payloadBody);
payloadObjects.Add(payloadObject);
inputStream.ReadByte();
break;
default:
throw new CorruptedFrameException("The Header is invalid: " + currentLine);
}
}
return(new Frame(command, sequenceNumber, vsKeyPairs, payloadObjects, routingObjects));
}
