string parsing problem??

[mankeyrabbit]

hi,
Im writing a client to connect to the MSN Messenger network. When connecting for the first time everything works fine, but, whne redirected by the server and opening a new connection, the parser goes strange. Ive put my code for the recv/parse function below. The problem is that instead of:

VER 1 MSNP7\r\n
INF 2 MD5\r\n

etc, i get:

ER 1 MSNP7\r\n
NF 2 MD5\r\n

which is strange because it works fine when opening the first connection. I have also noticed that if i throw an ASSERT exception, everything seems to work fine also. could someone please help me?

void recieveData()
{

	char buffer;
	CString cmd("a", 4299);
	int index = 0;
	while(true)
	{
		int nbytes = recv(ns->socket, &buffer, sizeof(unsigned char), 0);
		if(nbytes == SOCKET_ERROR)
		{
	//		log_write("Recieve error: %d", WSAGetLastError());
			buffer = '0';
		}
		else
		{
		if((nbytes >= 0))
		{
			log_write("%c, %d\n", buffer, index);
				char *cmdStr = cmd.GetBuffer(4298);
			ASSERT(index < 4298); // if assert is not thrown, result is for some reason garbled.
			cmdStr[index] = buffer;
//			cmd.SetAt(index, buffer);

			index++;
			if(buffer == '\n')
			{
				cmd.SetAt(index, '\0');
				cmd = cmd.Left(index);
				log_write("%s", cmd);
				serverwindow_write((char *)((const char *)cmd), JM_RECIEVED);
				int end = cmd.Find(" ", 4);
				int l = end - 4;
				CString id = CString(' ', 6);
				for(int i = 0; i < l; i++)
				{
					id.SetAt(i, cmd[i + 4]);
				}
				stringtoint((char *)((const char *)id), recievedMsg.trID);
				recievedMsg.cmd[0] = cmd[0];
				recievedMsg.cmd[1] = cmd[1];
				recievedMsg.cmd[2] = cmd[2];
				CString parms = cmd.Right(cmd.GetLength() - end - 1);
				parms = parms.Left(parms.GetLength() - 2);
				parms += '\0';

				recievedMsg.nParams = 0;
				recievedMsg.params = new char *[10];
				int b = 0;
				int e = 0;
				int k = 0;
				if(parms.Find(' ', 0) == -1) // if there is only one parameter
				{
					recievedMsg.params = new char *[1];
					recievedMsg.params[0] = new char[parms.GetLength()];
					strcpy(recievedMsg.params[0], parms.GetBuffer(parms.GetLength()));
					recievedMsg.nParams = 1;
				}
				else
				{
				while(e != parms.GetLength())
				{
					if(b != 0) {b = e + 1;}
					e = parms.Find(' ', b);
					if(e == -1) e = parms.GetLength();
					recievedMsg.params[k] = new char[e - b];
					recievedMsg.nParams++;
					for(i = 0; i < (e - b); i++)
					{
						char c = parms.GetAt(b + i);
						strcpy(&(recievedMsg.params[k])[i], &c);
					}
					strcpy(&(recievedMsg.params[k])[e-b], "\0");
					k++;
					if(b == 0) {b++;}
				}
				}
				cmdsWaiting = true;
				cmd.Empty();
				cmd = CString("a", 4299);
				index = 0;
				buffer = NULL;
			}
		}
	}
}
}

thanks

[j0nas]

First, I have to say that your code is a bit hard to understand/read... Why don't you implement a function that reads a whole string from a socket stream?

That would clear up things... Your bug is that you lose one char (at some point).

With a string read function, the parsing would be a lot simplier.

[kuphryn]

It is difficult to debug your code. There is no comment. How did you come up with the solution? Did you design it or was it a shot in the dark?

Kuphryn