NetBSD/lib/libc/resolv/res_compat.c
christos 4b05f4b58a Jump through taller hoops to provide binary compatibility with programs
compiled with the older and shorter _res. We now use _nres internally
which is the new and bigger one.  We define a _res which is the old
size one if COMPAT__RES is set, and then we consult selected values from
this old _res in res_init(), to emulate the old behavior.
2004-06-09 18:07:03 +00:00

84 lines
3.0 KiB
C

/* $NetBSD: res_compat.c,v 1.1 2004/06/09 18:07:03 christos Exp $ */
/*-
* Copyright (c) 2004 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Christos Zoulas.
*
* 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 NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
__RCSID("$NetBSD: res_compat.c,v 1.1 2004/06/09 18:07:03 christos Exp $");
#endif
#include <sys/types.h>
#include <arpa/inet.h>
#include <arpa/nameser.h>
#include <netdb.h>
#include <string.h>
#define __OLD_RES_STATE
#include <resolv.h>
#undef _res
/*
* Binary Compatibility; this symbol does not appear in a header file
* Most userland programs use this to set res_options before res_init()
* is called. There are hooks to res_init() to consult the data in this
* structure. The hooks are provided indirectly by the two functions below.
* We depend on the fact the the first 440 [32 bit machines] bytes are
* shared between the two structures.
*/
#ifndef __BIND_NOSTATIC
struct __res_state _res
#if defined(__BIND_RES_TEXT)
= { RES_TIMEOUT, } /* Motorola, et al. */
# endif
;
void *__res_get_old_state(void);
void __res_put_old_state(void *);
void *
__res_get_old_state(void)
{
return &_res;
}
void
__res_put_old_state(void *res)
{
(void)memcpy(&_res, res, sizeof(_res));
}
#endif