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/*
* $Id: hostname.c,v 1.1 1999/12/07 23:14:59 andersen Exp $
* Mini hostname implementation for busybox
*
* Copyright (C) 1999 by Randolph Chung <tausq@debian.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "internal.h"
#include <errno.h>
#include <getopt.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <unistd.h>
#include <stdio.h>
static const char* hostname_usage = "hostname [OPTION] {hostname | -F file}\n\n"
"Options:\n"
"\t-s, --short\t\tshort\n"
"\t-i, --ip-address\t\taddresses for the hostname\n"
"\t-d, --domain\t\tDNS domain name\n"
"If a hostname is given, or a file is given with the -F parameter, the host\n"
"name will be set\n";
static char short_opts[] = "sidF:";
static const struct option long_opts[] = {
{ "short", no_argument, NULL, 's' },
{ "ip-address", no_argument, NULL, 'i' },
{ "domain", no_argument, NULL, 'd' },
{ NULL, 0, NULL, 0 }
};
void do_sethostname(char *s, int isfile)
{
FILE *f;
char buf[255];
if (!s) return;
if (!isfile) {
if (sethostname(s, strlen(s)) < 0) {
if (errno == EPERM)
fprintf(stderr, "hostname: you must be root to change the hostname\n");
else
perror("sethostname");
exit(1);
}
} else {
if ((f = fopen(s, "r")) == NULL) {
perror(s);
exit(1);
} else {
fgets(buf, 255, f);
fclose(f);
if (buf[strlen(buf)-1] == '\n') buf[strlen(buf)-1] = 0;
if (sethostname(buf, strlen(buf)) < 0) {
perror("sethostname");
exit(1);
}
}
}
}
int hostname_main(int argc, char **argv)
{
int c;
int opt_short = 0;
int opt_domain = 0;
int opt_ip = 0;
int opt_file = 0;
struct hostent *h;
char *filename = NULL;
char buf[255];
char *s = NULL;
if (argc < 1) usage(hostname_usage);
while ((c = getopt_long(argc, argv, short_opts, long_opts, NULL)) != -1) {
switch (c) {
case 's': opt_short = 1; break;
case 'i': opt_ip = 1; break;
case 'd': opt_domain = 1; break;
case 'F': opt_file = 1; filename = optarg; break;
default: usage(hostname_usage);
}
}
if (optind < argc) {
do_sethostname(argv[optind], 0);
} else if (opt_file) {
do_sethostname(filename, 1);
} else {
gethostname(buf, 255);
if (opt_short) {
s = strchr(buf, '.');
if (!s) s = buf; *s = 0;
printf("%s\n", buf);
} else if (opt_domain) {
s = strchr(buf, '.');
printf("%s\n", (s ? s+1 : ""));
} else if (opt_ip) {
h = gethostbyname(buf);
if (!h) {
printf("Host not found\n");
exit(1);
}
printf("%s\n", inet_ntoa(*(struct in_addr *)(h->h_addr)));
} else {
printf("%s\n", buf);
}
}
return 0;
}
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