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authorEric Andersen2001-06-12 22:21:24 +0000
committerEric Andersen2001-06-12 22:21:24 +0000
commitdab3d46b9d35e0a0279b3700fe411f876bb25781 (patch)
tree929770563fe1fb9df68e8cb70fdc62f24dbeb68c /networking/nslookup.c
parent583e3ca45609dd3cb208b9134b7b96f581b4baf1 (diff)
downloadbusybox-dab3d46b9d35e0a0279b3700fe411f876bb25781.zip
busybox-dab3d46b9d35e0a0279b3700fe411f876bb25781.tar.gz
A patch from Benjamin Zeckel <bzeckel@cisco.com> to allow
nslookup.c to display the correct default nameservers.
Diffstat (limited to 'networking/nslookup.c')
-rw-r--r--networking/nslookup.c79
1 files changed, 40 insertions, 39 deletions
diff --git a/networking/nslookup.c b/networking/nslookup.c
index 8791b5e..1c75bb5 100644
--- a/networking/nslookup.c
+++ b/networking/nslookup.c
@@ -31,6 +31,8 @@
#include <sys/socket.h>
#include <sys/types.h>
#include <netinet/in.h>
+#include <resolv.h>
+#include <arpa/inet.h>
#include "busybox.h"
/*
@@ -39,19 +41,8 @@
|
| [ TODO ]
| + find out how to use non-default name servers
- | + find out how the real nslookup gets the default name server
*/
-/* I have to see how the real nslookup does this.
- * I could dig through /etc/resolv.conf, but is there a
- * better (programatic) way?
- */
-static inline void server_print(void)
-{
- printf("Server: %s\n", "default");
- printf("Address: %s\n\n", "default");
-}
-
/* only works for IPv4 */
static int addr_fprint(char *addr)
{
@@ -68,24 +59,6 @@ static int addr_fprint(char *addr)
return 0;
}
-/* changes a c-string matching the perl regex \d+\.\d+\.\d+\.\d+
- * into a u_int32_t
- */
-static u_int32_t str_to_addr(const char *addr)
-{
- u_int32_t split[4];
- u_int32_t ip;
-
- sscanf(addr, "%d.%d.%d.%d",
- &split[0], &split[1], &split[2], &split[3]);
-
- /* assuming sscanf worked */
- ip = (split[0] << 24) |
- (split[1] << 16) | (split[2] << 8) | (split[3]);
-
- return htonl(ip);
-}
-
/* takes the NULL-terminated array h_addr_list, and
* prints its contents appropriately
*/
@@ -116,15 +89,6 @@ static int addr_list_fprint(char **h_addr_list)
return 0;
}
-/* gethostbyaddr wrapper */
-static struct hostent *gethostbyaddr_wrapper(const char *address)
-{
- struct in_addr addr;
-
- addr.s_addr = str_to_addr(address);
- return gethostbyaddr((char *) &addr, 4, AF_INET); /* IPv4 only for now */
-}
-
/* print the results as nslookup would */
static struct hostent *hostent_fprint(struct hostent *host)
{
@@ -137,6 +101,42 @@ static struct hostent *hostent_fprint(struct hostent *host)
return host;
}
+/* changes a c-string matching the perl regex \d+\.\d+\.\d+\.\d+
+ * into a u_int32_t
+ */
+static u_int32_t str_to_addr(const char *addr)
+{
+ u_int32_t split[4];
+ u_int32_t ip;
+
+ sscanf(addr, "%d.%d.%d.%d",
+ &split[0], &split[1], &split[2], &split[3]);
+
+ /* assuming sscanf worked */
+ ip = (split[0] << 24) |
+ (split[1] << 16) | (split[2] << 8) | (split[3]);
+
+ return htonl(ip);
+}
+
+/* gethostbyaddr wrapper */
+static struct hostent *gethostbyaddr_wrapper(const char *address)
+{
+ struct in_addr addr;
+
+ addr.s_addr = str_to_addr(address);
+ return gethostbyaddr((char *) &addr, 4, AF_INET); /* IPv4 only for now */
+}
+
+/* lookup the default nameserver and display it */
+static inline void server_print(void)
+{
+ struct sockaddr_in def = _res.nsaddr_list[0];
+ char *ip = inet_ntoa(def.sin_addr);
+
+ hostent_fprint(gethostbyaddr_wrapper(ip));
+ printf("\n");
+}
/* naive function to check whether char *s is an ip address */
static int is_ip_address(const char *s)
@@ -160,6 +160,7 @@ int nslookup_main(int argc, char **argv)
show_usage();
}
+ res_init();
server_print();
if (is_ip_address(argv[1])) {
host = gethostbyaddr_wrapper(argv[1]);
@@ -170,4 +171,4 @@ int nslookup_main(int argc, char **argv)
return EXIT_SUCCESS;
}
-/* $Id: nslookup.c,v 1.22 2001/02/20 06:14:08 andersen Exp $ */
+/* $Id: nslookup.c,v 1.23 2001/06/12 22:21:24 andersen Exp $ */