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/* Copyright (C) 1997-2017 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 <errno.h>
#include <signal.h>
#include <string.h>
#include <sysdep.h>
#include <sys/syscall.h>
/* The difference here is that the sigaction structure used in the
kernel is not the same as we use in the libc. Therefore we must
translate it here. */
#include <kernel_sigaction.h>
#define SA_RESTORER 0x04000000
extern void __default_sa_restorer (void);
extern void __default_rt_sa_restorer (void);
/* When RT signals are in use we need to use a different return stub. */
#define choose_restorer(flags) \
(flags & SA_SIGINFO) ? __default_rt_sa_restorer \
: __default_sa_restorer
/* If ACT is not NULL, change the action for SIG to *ACT.
If OACT is not NULL, put the old action for SIG in *OACT. */
int
__libc_sigaction (int sig, const struct sigaction *act, struct sigaction *oact)
{
int result;
struct kernel_sigaction kact, koact;
if (act)
{
kact.k_sa_handler = act->sa_handler;
memcpy (&kact.sa_mask, &act->sa_mask, sizeof (sigset_t));
kact.sa_flags = act->sa_flags;
#ifdef HAVE_SA_RESTORER
if (kact.sa_flags & SA_RESTORER)
kact.sa_restorer = act->sa_restorer;
else
{
kact.sa_restorer = choose_restorer (kact.sa_flags);
kact.sa_flags |= SA_RESTORER;
}
#endif
}
/* XXX The size argument hopefully will have to be changed to the
real size of the user-level sigset_t. */
result = INLINE_SYSCALL (rt_sigaction, 4, sig,
act ? &kact : NULL,
oact ? &koact : NULL, _NSIG / 8);
if (oact && result >= 0)
{
oact->sa_handler = koact.k_sa_handler;
memcpy (&oact->sa_mask, &koact.sa_mask, sizeof (sigset_t));
oact->sa_flags = koact.sa_flags;
#ifdef HAVE_SA_RESTORER
oact->sa_restorer = koact.sa_restorer;
#endif
}
return result;
}
libc_hidden_def (__libc_sigaction)
#include <nptl/sigaction.c>
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