uclibc-ng/libc/sysdeps/linux/sparc64/sigaction.c

/* POSIX.1 sigaction call for Linux/SPARC64.
   Copyright (C) 1997-2017 Free Software Foundation, Inc.
   Contributed by Miguel de Icaza <miguel@nuclecu.unam.mx> and
		  Jakub Jelinek <jj@ultra.linux.cz>.

   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 <string.h>
#include <syscall.h>
#include <sysdep.h>
#include <sys/signal.h>
#include <errno.h>
#include <bits/kernel_sigaction.h>

/* SPARC 64bit userland requires a kernel that has rt signals anyway. */

static void __rt_sigreturn_stub (void);

int __libc_sigaction (int sig, const struct sigaction *act, struct sigaction *oact)
{
  int ret;
  struct kernel_sigaction kact, koact;
  unsigned long stub = ((unsigned long) &__rt_sigreturn_stub) - 8;

  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;
      kact.sa_restorer = NULL;
  }

  /* XXX The size argument hopefully will have to be changed to the
     real size of the user-level sigset_t.  */
  ret = INLINE_SYSCALL (rt_sigaction, 5, sig,
			act ? &kact : 0,
			oact ? &koact : 0, stub, _NSIG / 8);

  if (oact && ret >= 0) {
      oact->sa_handler = koact.k_sa_handler;
      memcpy (&oact->sa_mask, &koact.sa_mask, sizeof (sigset_t));
      oact->sa_flags = koact.sa_flags;
      oact->sa_restorer = koact.sa_restorer;
  }

  return ret;
}

#ifndef LIBC_SIGACTION
# ifndef __UCLIBC_HAS_THREADS__
strong_alias(__libc_sigaction,sigaction)
libc_hidden_def(sigaction)
# else
weak_alias(__libc_sigaction,sigaction)
libc_hidden_weak(sigaction)
# endif
#endif

static void
__rt_sigreturn_stub (void)
{
  __asm__ ("mov %0, %%g1\n\t"
	   "ta	0x6d\n\t"
	   : /* no outputs */
	   : "i" (__NR_rt_sigreturn));
}