1/*      $NetBSD: hijackdlsym.c,v 1.1 2011/02/23 15:23:15 pooka Exp $	*/
2
3/*-
4 * Copyright (c) 2011 Antti Kantee.  All Rights Reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
16 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
17 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
18 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
21 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28#include <sys/cdefs.h>
29__RCSID("$NetBSD: hijackdlsym.c,v 1.1 2011/02/23 15:23:15 pooka Exp $");
30
31#include <dlfcn.h>
32
33#include "hijack.h"
34
35/*
36 * This is called from librumpclient in case of LD_PRELOAD.
37 * It ensures correct RTLD_NEXT.
38 *
39 * (note, this module is compiled with -O0 to make sure this
40 * function is not treated as a tailcall or other optimizations
41 * applied)
42 */
43
44/* why is this indirection required for powerpc ???? */
45static void * __noinline
46bouncer(void *handle, const char *symbol)
47{
48
49	return dlsym(handle, symbol);
50}
51
52void *
53rumphijack_dlsym(void *handle, const char *symbol)
54{
55
56	return bouncer(handle, symbol);
57}
58