xref: /csrg-svn/lib/libc/net/res_init.c (revision 18548)
118142Sralph #ifndef lint
2*18548Sralph static char sccsid[] = "@(#)res_init.c	4.4 (Berkeley) 04/01/85";
318142Sralph #endif
418142Sralph 
5*18548Sralph /*
6*18548Sralph  * Copyright (c) 1985 Regents of the University of California
7*18548Sralph  *	All Rights Reserved
8*18548Sralph  */
9*18548Sralph 
1018142Sralph #include <sys/types.h>
1118142Sralph #include <sys/socket.h>
1218142Sralph #include <netinet/in.h>
1318142Sralph #include <stdio.h>
1418142Sralph #include <nameser.h>
1518142Sralph #include <resolv.h>
1618142Sralph 
1718142Sralph /*
1818142Sralph  * Resolver state default settings
1918142Sralph  */
2018142Sralph struct state _res = {
2118142Sralph 	90,
2218142Sralph 	2,
2318142Sralph 	RES_RECURSE|RES_DEFNAMES,
2418142Sralph };
2518142Sralph 
2618142Sralph /*
2718142Sralph  * Read the configuration file for default settings.
2818142Sralph  * Return true if the name server address is initialized.
2918142Sralph  */
3018142Sralph res_init()
3118142Sralph {
3218142Sralph 	FILE *fp;
3318142Sralph 	char buf[BUFSIZ], *cp;
3418142Sralph 	int n;
3518142Sralph 	extern u_long inet_addr();
3618527Sralph 	extern char *index(), *getenv();
3718142Sralph 
3818142Sralph 	_res.options |= RES_INIT;
3918142Sralph 	_res.nsaddr.sin_family = AF_INET;
4018142Sralph 	_res.nsaddr.sin_addr.s_addr = INADDR_ANY;
4118527Sralph 	_res.nsaddr.sin_port = HTONS(NAMESERVER_PORT);
4218142Sralph 
4318142Sralph 	/* first try reading the config file */
4418142Sralph 	if ((fp = fopen(CONFFILE, "r")) != NULL) {
4518527Sralph 		if (fgets(_res.defdname, sizeof(_res.defdname), fp) == NULL)
4618142Sralph 			_res.defdname[0] = '\0';
4718142Sralph 		else if ((cp = index(_res.defdname, '\n')) != NULL)
4818142Sralph 			*cp = '\0';
4918527Sralph 		if (fgets(buf, sizeof (buf), fp) != NULL)
5018142Sralph 			_res.nsaddr.sin_addr.s_addr = inet_addr(buf);
5118142Sralph 		(void) fclose(fp);
5218142Sralph 	}
5318142Sralph 
5418527Sralph 	/* Allow user to override the local domain definition */
5518527Sralph 	if ((cp = getenv("LOCALDOMAIN")) != NULL)
5618527Sralph 		strncpy(_res.defdname, cp, sizeof(_res.defdname));
5718142Sralph }
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