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/* BSD-like signal function.
Copyright (C) 1991,1992,1996,1997,2000,2002,2005
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> /* For the real memset prototype. */
sigset_t _sigintr; /* Set by siginterrupt. */
/* Set the handler for the signal SIG to HANDLER,
returning the old handler, or SIG_ERR on error. */
__sighandler_t
signal (int sig, __sighandler_t handler)
{
struct sigaction act, oact;
/* Check signal extents to protect __sigismember. */
if (handler == SIG_ERR || sig < 1 || sig >= NSIG)
{
__set_errno (EINVAL);
return SIG_ERR;
}
act.sa_handler = handler;
__sigemptyset (&act.sa_mask);
__sigaddset (&act.sa_mask, sig);
act.sa_flags = __sigismember (&_sigintr, sig) ? 0 : SA_RESTART;
/* In Linux (as of 2.6.25), fails only if sig is SIGKILL or SIGSTOP */
if (sigaction (sig, &act, &oact) < 0)
return SIG_ERR;
return oact.sa_handler;
}
libc_hidden_def(signal)
#ifdef __UCLIBC_SUSV3_LEGACY__
strong_alias(signal,bsd_signal)
#endif
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