mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-26 23:10:06 +00:00
900e445fad
* nptl/pt-vfork.c (vfork_resolve): Rename from vfork_ifunc. (vfork, __vfork): Define via compat_symbol.
78 lines
2.8 KiB
C
78 lines
2.8 KiB
C
/* vfork ABI-compatibility entry points for libpthread.
|
|
Copyright (C) 2014 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
The GNU C Library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with the GNU C Library; if not, see
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
#include <unistd.h>
|
|
#include <shlib-compat.h>
|
|
|
|
/* libpthread used to have its own vfork implementation that differed
|
|
from libc's only in having a pointless micro-optimization. There
|
|
is no longer any use to having a separate copy in libpthread, but
|
|
the historical ABI requires it. For static linking, there is no
|
|
need to provide anything here--the libc version will be linked in.
|
|
For shared library ABI compatibility, there must be __vfork and
|
|
vfork symbols in libpthread.so; so we define them using IFUNC to
|
|
redirect to the libc function. */
|
|
|
|
/* Note! If the architecture doesn't support IFUNC, then we need an
|
|
alternate target-specific mechanism to implement this. So we just
|
|
assume IFUNC here and require that the target override this file
|
|
if necessary.
|
|
|
|
If the architecture can assume all supported versions of gcc will
|
|
produce a tail-call to __libc_vfork, consider including the version
|
|
in sysdeps/unix/sysv/linux/aarch64/pt-vfork.c. */
|
|
|
|
#if !HAVE_IFUNC
|
|
# error "must write pt-vfork for this machine or get IFUNC support"
|
|
#endif
|
|
|
|
#if (SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_20) \
|
|
|| SHLIB_COMPAT (libpthread, GLIBC_2_1_2, GLIBC_2_20))
|
|
|
|
extern __typeof (vfork) __libc_vfork; /* Defined in libc. */
|
|
|
|
static __typeof (vfork) *
|
|
__attribute__ ((used))
|
|
vfork_resolve (void)
|
|
{
|
|
return &__libc_vfork;
|
|
}
|
|
|
|
# ifdef HAVE_ASM_SET_DIRECTIVE
|
|
# define DEFINE_VFORK(name) \
|
|
asm (".set " #name ", vfork_resolve\n" \
|
|
".globl " #name "\n" \
|
|
".type " #name ", %gnu_indirect_function");
|
|
# else
|
|
# define DEFINE_VFORK(name) \
|
|
asm (#name " = vfork_resolve\n" \
|
|
".globl " #name "\n" \
|
|
".type " #name ", %gnu_indirect_function");
|
|
# endif
|
|
#endif
|
|
|
|
#if SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_20)
|
|
DEFINE_VFORK (vfork_ifunc)
|
|
compat_symbol (libpthread, vfork_ifunc, vfork, GLIBC_2_0);
|
|
#endif
|
|
|
|
#if SHLIB_COMPAT (libpthread, GLIBC_2_1_2, GLIBC_2_20)
|
|
DEFINE_VFORK (__vfork_ifunc)
|
|
compat_symbol (libpthread, __vfork_ifunc, __vfork, GLIBC_2_1_2);
|
|
#endif
|