X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=networking%2Fnslookup.c;h=8e3c8fed9af02f79755c789001c2d285ef9a0f0f;hb=179e88bec91cfe58096900dc5509a080ff37b083;hp=67fc01547c67d71aeef5c3b01f8b8edc9ca24d2d;hpb=7f4b769c42f3773ff2e2e749547291dcb7e85d01;p=oweals%2Fbusybox.git

diff --git a/networking/nslookup.c b/networking/nslookup.c
index 67fc01547..8e3c8fed9 100644
--- a/networking/nslookup.c
+++ b/networking/nslookup.c
@@ -10,6 +10,29 @@
  *
  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  */
+//config:config NSLOOKUP
+//config:	bool "nslookup"
+//config:	default y
+//config:	help
+//config:	  nslookup is a tool to query Internet name servers.
+
+//applet:IF_NSLOOKUP(APPLET(nslookup, BB_DIR_USR_BIN, BB_SUID_DROP))
+
+//kbuild:lib-$(CONFIG_NSLOOKUP) += nslookup.o
+
+//usage:#define nslookup_trivial_usage
+//usage:       "[HOST] [SERVER]"
+//usage:#define nslookup_full_usage "\n\n"
+//usage:       "Query the nameserver for the IP address of the given HOST\n"
+//usage:       "optionally using a specified DNS server"
+//usage:
+//usage:#define nslookup_example_usage
+//usage:       "$ nslookup localhost\n"
+//usage:       "Server:     default\n"
+//usage:       "Address:    default\n"
+//usage:       "\n"
+//usage:       "Name:       debian\n"
+//usage:       "Address:    127.0.0.1\n"
 
 #include <resolv.h>
 #include "libbb.h"
@@ -124,6 +147,9 @@ static void set_default_dns(const char *server)
 {
 	len_and_sockaddr *lsa;
 
+	if (!server)
+		return;
+
 	/* NB: this works even with, say, "[::1]:5353"! :) */
 	lsa = xhost2sockaddr(server, 53);
 
@@ -167,9 +193,17 @@ int nslookup_main(int argc, char **argv)
 	/* (but it also says "may be enabled in /etc/resolv.conf") */
 	/*_res.options |= RES_USE_INET6;*/
 
-	if (argv[2])
-		set_default_dns(argv[2]);
+	set_default_dns(argv[2]);
 
 	server_print();
+
+	/* getaddrinfo and friends are free to request a resolver
+	 * reinitialization. Just in case, set_default_dns() again
+	 * after getaddrinfo (in server_print). This reportedly helps
+	 * with bug 675 "nslookup does not properly use second argument"
+	 * at least on Debian Wheezy and Openwrt AA (eglibc based).
+	 */
+	set_default_dns(argv[2]);
+
 	return print_host(argv[1], "Name:");
 }