1/* ABI compatibility for 'system' symbol in libpthread ABI.
2 Copyright (C) 2002-2016 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
5
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
10
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
15
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, see
18 <http://www.gnu.org/licenses/>. */
19
20#include <stdlib.h>
21#include <shlib-compat.h>
22
23/* libpthread once had its own 'system', though there was no apparent
24 reason for it. There is no use in having a separate symbol in
25 libpthread, but the historical ABI requires it. For static linking,
26 there is no need to provide anything here--the libc version will be
27 linked in. For shared library ABI compatibility, there must be a
28 'system' symbol in libpthread.so; so we define it using IFUNC to
29 redirect to the libc function. */
30
31#if SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_22)
32
33# if HAVE_IFUNC
34
35static __typeof (system) *
36__attribute__ ((used))
37system_resolve (void)
38{
39 return &__libc_system;
40}
41
42asm (".globl system_ifunc\n"
43 ".type system_ifunc, %gnu_indirect_function");
44
45# ifdef HAVE_ASM_SET_DIRECTIVE
46asm (".set system_ifunc, system_resolve");
47# else
48asm ("system_ifunc = system_resolve");
49# endif
50
51# else /* !HAVE_IFUNC */
52
53static int __attribute__ ((used))
54system_compat (const char *line)
55{
56 return __libc_system (line);
57}
58strong_alias (system_compat, system_ifunc)
59
60# endif /* HAVE_IFUNC */
61
62compat_symbol (libpthread, system_ifunc, system, GLIBC_2_0);
63
64#endif
65