Jcowdy at 21:22, 16 June 2011

2011-06-16T21:22:45Z

Jcowdy: Created page with '== About == This is a simple TCP usage example. It is an echo test client that sends a message to the echo server and then prints out the reply. The echo protocol is defined in R...'

2011-06-10T19:50:30Z

Created page with '== About == This is a simple TCP usage example. It is an echo test client that sends a message to the echo server and then prints out the reply. The echo protocol is defined in R...'

New page

== About ==
This is a simple TCP usage example. It is an echo test client that sends a message to the echo server and then prints out the reply.
The echo protocol is defined in RFC 862. In short, we send a message to the server, and the server echos the exact same message back.

== Usage ==
* Add the the to the shell directory as xsh_echotest.c
* Modify shell.c and shell.h to include the echotest command.
* Modify the Makefile in the shell directory to include xsh_echotest.c and then make XINU from the compile directory
* Boot XINU
* Run netup command from the shell
* Run echoclient from the shell with the arguments of the echoserver's ip and the message to be sent in quotes
**eg: echoclient 192.168.6.102 "Hello XINU World!"

== echotest.c ==
<nowiki>#include <stddef.h>
#include <stdio.h>
#include <device.h>
#include <ether.h>
#include <tcp.h>
#include <string.h>

#define MSG_MAX_LEN 64
#define ECHO_PORT 7

/**
* Shell command (echotest) sends a message to an echo server per RFC 862.
* It waits for a response, then prints out the reply from the echo server.
* Expects args: echotest, echo server ip, Message to echo in quotes
* @param nargs number of arguments in args array
* @param args array of arguments
* @return non-zero value on error
*/
shellcmd xsh_echotest(int nargs, char *args[])
{
ushort dev = 0;
char buf[MSG_MAX_LEN];

char *dest = args[1];

struct netaddr dst;
struct netaddr *localhost;
struct netif *interface;

int len;

/* Allocate a new TCP device */
if ((ushort)SYSERR == (dev = tcpAlloc()))
{
fprintf(stderr, "Client: Failed to allocate a TCP device.");
return SYSERR;
}

/* Look up local ip info */
interface = netLookup((ethertab[0].dev)->num);
if (NULL == interface)
{
fprintf(stderr, "Client: No network interface found\r\n");
return SYSERR;
}
localhost = &(interface->ip);

/* Change the destination to ipv4 */
if (SYSERR == dot2ipv4(dest, &dst))
{
fprintf(stderr, "Client: Failed to convert ip address.");
return SYSERR;
}

/* Open the TCP device with the destination and echo port*/
if (SYSERR == open(dev, localhost, &dst, NULL, ECHO_PORT, TCP_ACTIVE))
{
fprintf(stderr, "Client: Could not open the UDP device\r\n");
return SYSERR;
}

/* Send the message to the destination*/
memcpy(buf, args[2], MSG_MAX_LEN);

if(SYSERR == write(dev, buf, MSG_MAX_LEN))
{
fprintf(stderr, "Client: Error writing packet to the network");
close(dev);
return SYSERR;
}

/* Read a response from the server */
if(SYSERR != (len = read(dev, buf, MSG_MAX_LEN)))
{
printf("Client: Got response - %s\r\n", buf);
}

/* Close the device when done */
close(dev);

return 0;
</nowiki>

@@ Line 12: / Line 12: @@
 **eg: echoclient 192.168.6.102 "Hello XINU World!"
-== echotest.c ==
+== xsh_echotest.c ==
   <nowiki>#include <stddef.h>
 #include <stdio.h>
@@ Line 70: / Line 70: @@
      if (SYSERR == open(dev, localhost, &dst, NULL, ECHO_PORT, TCP_ACTIVE))
+     {
-         fprintf(stderr, "Client: Could not open the UDP device\r\n");
+         fprintf(stderr, "Client: Could not open the TCP device\r\n");
          return SYSERR;
+     }
@@ Line 94: / Line 94: @@
      return 0;
 </nowiki>

TCP Echo Test - Revision history

Jcowdy at 21:22, 16 June 2011

Jcowdy: Created page with '== About == This is a simple TCP usage example. It is an echo test client that sends a message to the echo server and then prints out the reply. The echo protocol is defined in R...'