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/* Copyright (C) 2008 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by David Bartley <dtbartle@csclub.uwaterloo.ca>, 2008.
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. */
#include <inline-syscall.h>
#include <errno.h>
#include <stddef.h>
#include <signal.h>
#include <string.h>
#include <ucontext.h>
#include <tls.h>
#include <assert.h>
#include <bits/libc-lock.h>
#include <stdio.h>
#include <socketP.h>
static void (*sighandlers[_NSIG])(int, struct siginfo *, void *) = {0};
static sigset_t sigmasks[_NSIG];
__libc_lock_define_initialized (, signal_lock);
/* Solaris expects the ucontext_t to be switched back at the end
of signal processing; one cannot simply return from the
sighandler. As well, Solaris always calls the 3-param version
of the handler (i.e. sa_sigaction). */
/* Defined in sighandler.c. */
extern void __sighandler(int, siginfo_t *, void *);
DECLARE_INLINE_SYSCALL (int, sigaction, int signum,
const struct sigaction *act, struct sigaction *oldact);
DECLARE_INLINE_SYSCALL (int64_t, lwp_sigmask, int how, unsigned int bits0,
unsigned int bits1);
int
__libc_sigaction (sig, act, oact)
int sig;
const struct sigaction *act;
struct sigaction *oact;
{
int result = -1;
if (sig < 0 || sig >= NSIG)
{
__set_errno (EINVAL);
return -1;
}
if (!act && !oact)
{
__set_errno (EINVAL);
return -1;
}
/* Block all signals and lock. */
rval_t oldmask;
oldmask.rval64 = INLINE_SYSCALL (lwp_sigmask, 3, SIG_SETMASK,
(unsigned int)-1, (unsigned int)-1);
__libc_lock_lock (signal_lock);
void (*old_sigaction)(int, siginfo_t *, void *) = sighandlers[sig];
sigset_t old_sigmask = sigmasks[sig];
if (act)
{
struct sigaction _act = *act;
if (act->sa_handler != SIG_DFL && act->sa_handler != SIG_IGN)
{
_act.sa_sigaction = __sighandler;
(void)sigfillset (&_act.sa_mask);
}
result = INLINE_SYSCALL (sigaction, 3, sig, &_act, oact);
if (result == 0)
{
sighandlers[sig] = act->sa_sigaction;
sigmasks[sig] = act->sa_mask;
}
}
if (oact)
{
/* If we called sigaction above don't call it again. */
if (!act)
result = INLINE_SYSCALL(sigaction, 3, sig, NULL, oact);
if (result == 0)
{
if (oact->sa_handler != SIG_DFL && oact->sa_handler != SIG_IGN)
{
oact->sa_sigaction = old_sigaction;
oact->sa_mask = old_sigmask;
}
}
}
/* Unlock and restore signals. */
__libc_lock_unlock (signal_lock);
(void)INLINE_SYSCALL (lwp_sigmask, 3, SIG_SETMASK,
(unsigned int)oldmask.rval1, (unsigned int)oldmask.rval2);
return result;
}
libc_hidden_def (__libc_sigaction)
#ifndef LIBC_SIGACTION
weak_alias (__libc_sigaction, __sigaction)
libc_hidden_weak (__sigaction)
weak_alias (__libc_sigaction, sigaction)
#endif
asm (".globl __sighandler_end");
void __sighandler (int sig, siginfo_t *sip, void *uvp)
{
assert (sig >= 0 && sig < NSIG);
ucontext_t *uctx = (ucontext_t*)uvp;
if (sig == SIGPIPE && SIGPIPE_IS_DISABLED)
{
setcontext (uctx);
assert (0); /* never reached */
}
/* All signals are blocked (we passed a filled sa_mask above). */
__libc_lock_lock (signal_lock);
void (*handler)(int, siginfo_t *, void *) = sighandlers[sig];
sigset_t mask = sigmasks[sig];
__libc_lock_unlock (signal_lock);
/* Set signals to wait sigaction wants. */
(void)INLINE_SYSCALL (lwp_sigmask, 3, SIG_SETMASK,
(unsigned int)mask.__sigbits[0], (unsigned int)mask.__sigbits[1]);
(*handler)(sig, sip, uvp);
setcontext (uctx);
assert (0); /* never reached */
}
asm ("__sighandler_end:");
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