www.pudn.com > vxWorks_Lab.rar > unixServer.c

/* unixServer - reads client requests and sends a reply. */ 
 
/* Copyright 1984-1994 Wind River Systems, Inc. */ 
 
/* 
modification history 
-------------------- 
01c,06apr98,dlk  removed free (pClientInet). 
01b,05dec94,bss  cleaned up.  WRS coding conventions enforced.  
01a,???????,???  written. 
*/ 
 
/* 
DESCRIPTION 
*/ 
 
/* includes */ 
 
#include  
#include  
#include  
#include  
#include  
 
/* defines */ 
 
#define MAX_MSG_LEN 80 
 
#define FOREVER for (;;)		/* for WRS coding conventions */ 
#define LOCAL static 
 
/* typedefs */ 
 
typedef int SOCK_FD; 
 
/* forward declarations */ 
 
LOCAL void error (); 
 
/******************************************************************************* 
 * 
 * main - entry point to unixServer 
 * 
 * This routine sets up a UDP socket and then sits in an infinite 
 * loop reading client messages, printing them to the console, and 
 * sending a reply. 
 */ 
 
main (argc, argv) 
	int argc; 
	char ** argv; 
	{ 
	short port; 
	int					clientAddrLength; 
	SOCK_FD				sockFd; 
	struct sockaddr_in	clientAddr; 
	struct sockaddr_in	srvAddr; 
	char				buf [MAX_MSG_LEN]; 
	char *				reply = "Here is your reply\n"; 
	u_short				clientPort; 
	char *				pClientInet; 
 
	clientAddrLength = sizeof (clientAddr); 
 
	/* Get the server port number */ 
	if (argc != 2) 
		{ 
		fprintf (stderr, "Usage: %s portNumber\n", argv[0]); 
		exit (1); 
		} 
	port = (short) atoi (argv [1]); 
 
	/* Create a socket */ 
	if ((sockFd = socket (PF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) 
		error ("Socket failed"); 
 
	/*  
	 * Bind to a well known address. INADDR_ANY says any network 
	 * interface will do. hton?() routines put things in network 
	 * byte order  
	 */ 
 
	bzero ((char *) &srvAddr, sizeof (srvAddr)); 
	srvAddr.sin_family		= AF_INET; 
	srvAddr.sin_port		= htons(port); 
	srvAddr.sin_addr.s_addr = INADDR_ANY; 
 
	if (bind (sockFd, &srvAddr, sizeof(srvAddr)) < 0) 
		{ 
		close (sockFd); 
		error ("Bind failed"); 
		} 
 
	FOREVER 
		{ 
		if (recvfrom (sockFd, buf, MAX_MSG_LEN, 0, &clientAddr, 
					  &clientAddrLength)  < 0) 
			{ 
			close (sockFd); 
			error ("recvfrom failed"); 
			} 
 
		clientPort = ntohs (clientAddr.sin_port); 
		pClientInet = inet_ntoa (clientAddr.sin_addr); 
 
		printf ("Message received from client (port = %d, inet = %s):\n", 
				clientPort, pClientInet); 
		printf ("%s\n", buf); 
 
		if (sendto (sockFd, reply, strlen(reply) + 1, 0, 
					&clientAddr, clientAddrLength) < 0) 
			{ 
			close (sockFd); 
			error ("sendto failed"); 
			} 
		} 
	} 
 
/******************************************************************************* 
 * 
 * error - aborts a process on an error  
 * 
 * This funcion displays the reason a process crashed  
 * and terminates that process. 
 */ 
 
LOCAL void error (pStr) 
	char * pStr; 
	{ 
	perror (pStr); 
	exit (1); 
	}