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-rw-r--r--lib/libc/net/res_init.c223
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diff --git a/lib/libc/net/res_init.c b/lib/libc/net/res_init.c
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+/*-
+ * Copyright (c) 1985, 1989, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * -
+ * Portions Copyright (c) 1993 by Digital Equipment Corporation.
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies, and that
+ * the name of Digital Equipment Corporation not be used in advertising or
+ * publicity pertaining to distribution of the document or software without
+ * specific, written prior permission.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
+ * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
+ * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
+ * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
+ * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
+ * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
+ * SOFTWARE.
+ * -
+ * --Copyright--
+ */
+
+#if defined(LIBC_SCCS) && !defined(lint)
+static char sccsid[] = "@(#)res_init.c 8.1 (Berkeley) 6/7/93";
+static char rcsid[] = "$Id: res_init.c,v 4.9.1.1 1993/05/02 22:43:03 vixie Rel $";
+#endif /* LIBC_SCCS and not lint */
+
+#include <sys/param.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <arpa/nameser.h>
+#include <resolv.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+/*
+ * Resolver state default settings
+ */
+
+struct __res_state _res = {
+ RES_TIMEOUT, /* retransmition time interval */
+ 4, /* number of times to retransmit */
+ RES_DEFAULT, /* options flags */
+ 1, /* number of name servers */
+};
+
+/*
+ * Set up default settings. If the configuration file exist, the values
+ * there will have precedence. Otherwise, the server address is set to
+ * INADDR_ANY and the default domain name comes from the gethostname().
+ *
+ * The configuration file should only be used if you want to redefine your
+ * domain or run without a server on your machine.
+ *
+ * Return 0 if completes successfully, -1 on error
+ */
+res_init()
+{
+ register FILE *fp;
+ register char *cp, **pp;
+ register int n;
+ char buf[BUFSIZ];
+ int nserv = 0; /* number of nameserver records read from file */
+ int haveenv = 0;
+ int havesearch = 0;
+
+#ifdef USELOOPBACK
+ _res.nsaddr.sin_addr = inet_makeaddr(IN_LOOPBACKNET, 1);
+#else
+ _res.nsaddr.sin_addr.s_addr = INADDR_ANY;
+#endif
+ _res.nsaddr.sin_family = AF_INET;
+ _res.nsaddr.sin_port = htons(NAMESERVER_PORT);
+ _res.nscount = 1;
+ _res.pfcode = 0;
+
+ /* Allow user to override the local domain definition */
+ if ((cp = getenv("LOCALDOMAIN")) != NULL) {
+ (void)strncpy(_res.defdname, cp, sizeof(_res.defdname));
+ if ((cp = strpbrk(_res.defdname, " \t\n")) != NULL)
+ *cp = '\0';
+ haveenv++;
+ }
+
+ if ((fp = fopen(_PATH_RESCONF, "r")) != NULL) {
+ /* read the config file */
+ while (fgets(buf, sizeof(buf), fp) != NULL) {
+ /* skip comments */
+ if ((*buf == ';') || (*buf == '#'))
+ continue;
+ /* read default domain name */
+ if (!strncmp(buf, "domain", sizeof("domain") - 1)) {
+ if (haveenv) /* skip if have from environ */
+ continue;
+ cp = buf + sizeof("domain") - 1;
+ while (*cp == ' ' || *cp == '\t')
+ cp++;
+ if ((*cp == '\0') || (*cp == '\n'))
+ continue;
+ (void)strncpy(_res.defdname, cp,
+ sizeof(_res.defdname) - 1);
+ if ((cp = strpbrk(_res.defdname, " \t\n")) != NULL)
+ *cp = '\0';
+ havesearch = 0;
+ continue;
+ }
+ /* set search list */
+ if (!strncmp(buf, "search", sizeof("search") - 1)) {
+ if (haveenv) /* skip if have from environ */
+ continue;
+ cp = buf + sizeof("search") - 1;
+ while (*cp == ' ' || *cp == '\t')
+ cp++;
+ if ((*cp == '\0') || (*cp == '\n'))
+ continue;
+ (void)strncpy(_res.defdname, cp,
+ sizeof(_res.defdname) - 1);
+ if ((cp = strchr(_res.defdname, '\n')) != NULL)
+ *cp = '\0';
+ /*
+ * Set search list to be blank-separated strings
+ * on rest of line.
+ */
+ cp = _res.defdname;
+ pp = _res.dnsrch;
+ *pp++ = cp;
+ for (n = 0; *cp && pp < _res.dnsrch + MAXDNSRCH; cp++) {
+ if (*cp == ' ' || *cp == '\t') {
+ *cp = 0;
+ n = 1;
+ } else if (n) {
+ *pp++ = cp;
+ n = 0;
+ }
+ }
+ /* null terminate last domain if there are excess */
+ while (*cp != '\0' && *cp != ' ' && *cp != '\t')
+ cp++;
+ *cp = '\0';
+ *pp++ = 0;
+ havesearch = 1;
+ continue;
+ }
+ /* read nameservers to query */
+ if (!strncmp(buf, "nameserver", sizeof("nameserver") - 1) &&
+ nserv < MAXNS) {
+ struct in_addr a;
+
+ cp = buf + sizeof("nameserver") - 1;
+ while (*cp == ' ' || *cp == '\t')
+ cp++;
+ if ((*cp != '\0') && (*cp != '\n') && inet_aton(cp, &a)) {
+ _res.nsaddr_list[nserv].sin_addr = a;
+ _res.nsaddr_list[nserv].sin_family = AF_INET;
+ _res.nsaddr_list[nserv].sin_port =
+ htons(NAMESERVER_PORT);
+ nserv++;
+ }
+ continue;
+ }
+ }
+ if (nserv > 1)
+ _res.nscount = nserv;
+ (void) fclose(fp);
+ }
+ if (_res.defdname[0] == 0) {
+ if (gethostname(buf, sizeof(_res.defdname)) == 0 &&
+ (cp = strchr(buf, '.')))
+ (void)strcpy(_res.defdname, cp + 1);
+ }
+
+ /* find components of local domain that might be searched */
+ if (havesearch == 0) {
+ pp = _res.dnsrch;
+ *pp++ = _res.defdname;
+ for (cp = _res.defdname, n = 0; *cp; cp++)
+ if (*cp == '.')
+ n++;
+ cp = _res.defdname;
+ for (; n >= LOCALDOMAINPARTS && pp < _res.dnsrch + MAXDFLSRCH;
+ n--) {
+ cp = strchr(cp, '.');
+ *pp++ = ++cp;
+ }
+ *pp++ = 0;
+ }
+ _res.options |= RES_INIT;
+ return (0);
+}
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