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/*
* $Id: hostname.c,v 1.3 1999/12/08 04:23:30 andersen Exp $
* Mini hostname implementation for busybox
*
* Copyright (C) 1999 by Randolph Chung <tausq@debian.org>
*
* adjusted by Erik Andersen <andersee@debian.org> to remove
* use of long options and GNU getopt. Improved the usage info.
*
* 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 <arpa/inet.h>
#include <netdb.h>
#include <unistd.h>
#include <stdio.h>
static const char* hostname_usage =
"hostname [OPTION] {hostname | -F file}\n\n"
"Get or set the hostname or DNS domain name. If a hostname is given\n"
"(or a file with the -F parameter), the host name will be set.\n\n"
"Options:\n"
"\t-s\t\tShort\n"
"\t-i\t\tAddresses for the hostname\n"
"\t-d\t\tDNS domain name\n"
"\t-F FILE\t\tUse the contents of FILE to specify the hostname\n";
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 opt_short = 0;
int opt_domain = 0;
int opt_ip = 0;
struct hostent *h;
char *filename = NULL;
char buf[255];
char *s = NULL;
if (argc < 1) usage(hostname_usage);
while (--argc > 0 && **(++argv) == '-') {
while (*(++(*argv))) {
switch (**argv) {
case 's':
opt_short = 1;
break;
case 'i':
opt_ip = 1;
break;
case 'd':
opt_domain = 1;
break;
case 'F':
filename = optarg;
if (--argc == 0) {
usage(hostname_usage);
}
filename = *(++argv);
break;
default:
usage(hostname_usage);
}
if (filename!=NULL)
break;
}
}
if (argc >= 1) {
do_sethostname(*argv, 0);
} else if (filename!=NULL) {
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);
}
}
exit( 0);
}
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