Update the resolver in libc to BIND9's one.

Since, res_sendsigned(3) and the friends use MD5 functions, it is
hard to include them without having MD5 functions in libc.  So,
res_sendsigned(3) is not merged into libc.

Since, res_update(3) in BIND9 is not binary compatible with our
res_update(3), res_update(3) is leaved as is, except some
necessary modifications.
The res_update(3) and the friends are not essential part of the
resolver.  They are not defined in resolv.h but defined in
res_update.h separately in BIND9.  Further, they are not called from
our tree.  So, I hide them from our resolv.h, but leave them only
for binary backward compatibility (perhaps, no one calls them).

Since, struct __res_state_ext is not exposed in BIND9, I hide it
from our resolv.h.  And, global variable _res_ext is removed.  It
breaks binary backward compatibility.  But, since it is not used from
outside of our libc, I think it is safe.

Reviewed by:	arch@ (no objection)

1 files changed, 2 insertions, 1 deletions

diff --git a/lib/libc/net/res_mkupdate.c b/lib/libc/net/res_mkupdate.c
index 4892235..29cb95a 100644
--- a/lib/libc/net/res_mkupdate.c
+++ b/lib/libc/net/res_mkupdate.c
@@ -39,6 +39,7 @@ __FBSDID("$FreeBSD$");
 #include <unistd.h>
 #include <ctype.h>
 
+#include "res_update.h"
 #include "res_config.h"
 
 static int getnum_str(u_char **, u_char *);
@@ -73,7 +74,7 @@ res_mkupdate(ns_updrec *rrecp_in, u_char *buf, int buflen) {
 	u_char *dnptrs[20], **dpp, **lastdnptr;
 
 	if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
-		h_errno = NETDB_INTERNAL;
+		RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
 		return (-1);
 	}