glibc/nptl/pt-fork.c
Florian Weimer f06f3f05b4 fork in libpthread cannot use IFUNC resolver [BZ #19861]
This commit only addresses the fork case, the vfork case has to be a
tail call, which is why the generic code needs an IFUNC resolver
there.
2016-06-01 07:14:42 +02:00

50 lines
1.9 KiB
C

/* ABI compatibility for 'fork' symbol in libpthread ABI.
Copyright (C) 2002-2016 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
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 once had its own fork, though there was no apparent reason
for it. There is no use in having a separate symbol 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 __fork and fork symbols in
libpthread.so.
With an IFUNC resolver, it would be possible to avoid the
indirection, but the IFUNC resolver might run before the
__libc_fork symbol has been relocated, in which case the IFUNC
resolver would not be able to provide the correct address. */
#if SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_22)
static pid_t __attribute__ ((used))
fork_compat (void)
{
return __libc_fork ();
}
strong_alias (fork_compat, fork_alias)
compat_symbol (libpthread, fork_alias, fork, GLIBC_2_0);
strong_alias (fork_compat, __fork_alias)
compat_symbol (libpthread, __fork_alias, __fork, GLIBC_2_0);
#endif