sigaction.c

Newlib 嵌入式 C库 标准实现代码

/* Copyright (C) 1997, 1998, 1999, 2000 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, write to the Free
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307 USA.  */

/* Modified 05/30/02 by Jeff Johnston, Red Hat Inc. */

#include <errno.h>
#include <signal.h>
#include <string.h>

#include <machine/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 __NR___rt_sigaction __NR_rt_sigaction

static _syscall4(int,__rt_sigaction,int,sig,
                 const struct kernel_sigaction *,act,
                 struct kernel_sigaction *,oact,size_t,size);

/* 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 (sig, act, oact)
     int sig;
     const struct sigaction *act;
     struct sigaction *oact;
{
  int result;
  struct kernel_sigaction kact, koact;
  /* Save the current error value for later.  We need not do this
     if we are guaranteed to have realtime signals.  */

  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 = act->sa_restorer;
    }

  /* XXX The size argument hopefully will have to be changed to the
     real size of the user-level sigset_t.  */
  result = __rt_sigaction (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;
      oact->sa_restorer = koact.sa_restorer;
    }

  return result;
}

weak_alias (__libc_sigaction, __sigaction)
weak_alias (__libc_sigaction, sigaction)