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/* @(#)udpd.c 1.6 2003/12/29 Connectathon Testsuite */
/*
* server for simple udp ping program.
* listens on socket for request, then echos back
* request from client.
*/
#define UDP_PORT 3457
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
static void
xxit(s)
char *s;
{
perror(s);
exit(1);
}
/*ARGSUSED*/
int
main(argc, argv)
int argc;
char **argv;
{
int s; /* socket */
struct sockaddr_in addr; /* socket address */
int ret;
#ifdef HAVE_SOCKLEN_T
socklen_t addrlen = sizeof(struct sockaddr_in);
#else
size_t addrlen = sizeof(struct sockaddr_in);
#endif
struct hostent *hp;
char buf[BUFSIZ];
if ((s = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0)
xxit("socket");
addr.sin_family = AF_INET;
addr.sin_port = htons(UDP_PORT);
addr.sin_addr.s_addr = INADDR_ANY;
if (bind(s, (struct sockaddr *)&addr, addrlen) < 0)
xxit("bind");
while(1) {
fprintf(stderr, "%s awaiting request\n", argv[0]);
addrlen = sizeof(struct sockaddr_in);
ret = recvfrom(s, buf, BUFSIZ, 0, (struct sockaddr *)&addr,
&addrlen);
if (ret < 0)
xxit("recvfrom");
#ifdef __STDC__
if (hp = gethostbyaddr((const char *)&addr.sin_addr,
sizeof(addr.sin_addr), AF_INET))
#else
if (hp = gethostbyaddr(&addr.sin_addr, sizeof(addr.sin_addr),
AF_INET))
#endif
fprintf(stderr, "\
%s: accepted request from host %s\n", argv[0], hp->h_name);
else
fprintf(stderr, "\
%s: accepted request from host %x\n", argv[0], addr.sin_addr.s_addr);
fprintf(stderr, " recvfrom ret %d\n", ret);
if (ret > 0) {
*buf = *buf + 1;
ret = sendto(s, buf, ret, 0, (struct sockaddr *)&addr,
addrlen);
fprintf(stderr, " sendto ret %d\n", ret);
}
}
}
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