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, 75 insertions, 0 deletions

diff --git a/lib/libc/net/res_update.h b/lib/libc/net/res_update.h
new file mode 100644
index 0000000..a9528c0
--- /dev/null
+++ b/lib/libc/net/res_update.h
@@ -0,0 +1,75 @@
+/*-
+ * Copyright (c) 1983, 1987, 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.
+ */
+
+/* $FreeBSD$ */
+
+#ifndef _RES_UPDATE_H_
+#define _RES_UPDATE_H_
+
+/*
+ * This RR-like structure is particular to UPDATE.
+ */
+struct ns_updrec {
+	struct ns_updrec *r_prev;	/* prev record */
+	struct ns_updrec *r_next;	/* next record */
+	u_int8_t	r_section;	/* ZONE/PREREQUISITE/UPDATE */
+	char *		r_dname;	/* owner of the RR */
+	u_int16_t	r_class;	/* class number */
+	u_int16_t	r_type;		/* type number */
+	u_int32_t	r_ttl;		/* time to live */
+	u_char *	r_data;		/* rdata fields as text string */
+	u_int16_t	r_size;		/* size of r_data field */
+	int		r_opcode;	/* type of operation */
+	/* following fields for private use by the resolver/server routines */
+	struct ns_updrec *r_grpnext;	/* next record when grouped */
+	struct databuf *r_dp;		/* databuf to process */
+	struct databuf *r_deldp;	/* databuf's deleted/overwritten */
+	u_int16_t	r_zone;		/* zone number on server */
+};
+typedef struct ns_updrec ns_updrec;
+
+#define	res_freeupdrec	__res_freeupdrec
+#define	res_mkupdate	__res_mkupdate
+#define	res_mkupdrec	__res_mkupdrec
+#if 0
+#define	res_update	__res_update
+#endif
+
+__BEGIN_DECLS
+void		res_freeupdrec(ns_updrec *);
+int		res_mkupdate(ns_updrec *, u_char *, int);
+ns_updrec *	res_mkupdrec(int, const char *, u_int, u_int, u_long);
+int		res_update(ns_updrec *);
+__END_DECLS
+
+#endif /* _RES_UPDATE_H_ */