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/* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/* tests/resolve/resolve.c */
/*
* Copyright 1995 by the Massachusetts Institute of Technology.
* All Rights Reserved.
*
* Export of this software from the United States of America may
* require a specific license from the United States Government.
* It is the responsibility of any person or organization contemplating
* export to obtain such a license before exporting.
*
* WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
* distribute this software and its documentation for any purpose and
* without fee is hereby granted, provided that the above copyright
* notice appear in all copies and that both that copyright notice and
* this permission notice appear in supporting documentation, and that
* the name of M.I.T. not be used in advertising or publicity pertaining
* to distribution of the software without specific, written prior
* permission. Furthermore if you modify this software you must label
* your software as modified software and not distribute it in such a
* fashion that it might be confused with the original M.I.T. software.
* M.I.T. makes no representations about the suitability of
* this software for any purpose. It is provided "as is" without express
* or implied warranty.
*/
/*
* A simple program to test the functionality of the resolver library.
* It simply will try to get the IP address of the host, and then look
* up the name from the address. If the resulting name does not contain the
* domain name, then the resolve library is broken.
*
* Warning: It is possible to fool this program into thinking everything is
* alright by a clever use of /etc/hosts - but this is better than nothing.
*
* Usage:
* resolve [hostname]
*
* When invoked with no arguments, gethostname is used for the local host.
*
*/
/* This program tests the resolve library and sees if it is broken... */
#include "autoconf.h"
#include <stdio.h>
#if STDC_HEADERS
#include <string.h>
#else
#ifndef HAVE_STRCHR
#define strchr index
#endif
char *strchr();
#endif
#ifdef HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <netinet/in.h>
#include <netdb.h>
#ifndef MAXHOSTNAMELEN
# define MAXHOSTNAMELEN 256
#endif
int
main(argc, argv)
int argc;
char **argv;
{
char myname[MAXHOSTNAMELEN+1];
char *ptr, *fqdn;
struct in_addr addrcopy;
struct hostent *host;
int quiet = 0;
argc--; argv++;
while (argc) {
if ((strcmp(*argv, "--quiet") == 0) ||
(strcmp(*argv, "-q") == 0)) {
quiet++;
} else
break;
argc--; argv++;
}
if (argc >= 1) {
strncpy(myname, *argv, MAXHOSTNAMELEN);
} else {
if(gethostname(myname, MAXHOSTNAMELEN)) {
perror("gethostname failure");
exit(1);
}
}
myname[MAXHOSTNAMELEN] = '\0'; /* for safety */
/* Look up the address... */
if (!quiet)
printf("Hostname: %s\n", myname);
/* Set the hosts db to close each time - effectively rewinding file */
sethostent(0);
if((host = gethostbyname (myname)) == NULL) {
fprintf(stderr,
"Could not look up address for hostname '%s' - fatal\n",
myname);
exit(2);
}
fqdn = strdup(host->h_name);
if (fqdn == NULL) {
perror("strdup");
exit(2);
}
ptr = host->h_addr_list[0];
#define UC(a) (((int)a)&0xff)
if (!quiet)
printf("Host address: %d.%d.%d.%d\n",
UC(ptr[0]), UC(ptr[1]), UC(ptr[2]), UC(ptr[3]));
memcpy(&addrcopy.s_addr, ptr, 4);
/* Convert back to full name */
if ((host = gethostbyaddr(&addrcopy.s_addr, 4, AF_INET)) == NULL) {
if (!quiet)
fprintf(stderr, "Error looking up IP address\n");
} else {
free(fqdn);
fqdn = strdup(host->h_name);
if (fqdn == NULL) {
perror("strdup");
exit (2);
}
}
if (quiet)
printf("%s\n", fqdn);
else
printf("FQDN: %s\n", fqdn);
if (!quiet)
printf("Resolve library appears to have passed the test\n");
/* All ok */
exit(0);
}
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