glibc/sysdeps/posix/sigvec.c

182 lines
4.4 KiB
C

/* Copyright (C) 1991-2013 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 <signal.h>
#include <errno.h>
#include <stddef.h>
/* Include macros to convert between `sigset_t' and old-style mask. */
#include <sigset-cvt-mask.h>
#ifndef SA_RESETHAND
/* When sigaction lacks the extension bit for it,
we use a wrapper handler to support SV_RESETHAND. */
struct sigvec_wrapper_data
{
__sighandler_t sw_handler;
unsigned int sw_mask;
};
static void sigvec_wrapper_handler (int sig) __THROW;
static struct sigvec_wrapper_data sigvec_wrapper_data[NSIG];
#endif
/* If VEC is non-NULL, set the handler for SIG to the `sv_handler' member
of VEC. The signals in `sv_mask' will be blocked while the handler runs.
If the SV_RESETHAND bit is set in `sv_flags', the handler for SIG will be
reset to SIG_DFL before `sv_handler' is entered. If OVEC is non-NULL,
it is filled in with the old information for SIG. */
int
__sigvec (sig, vec, ovec)
int sig;
const struct sigvec *vec;
struct sigvec *ovec;
{
struct sigaction old;
#ifndef SA_RESETHAND
if (vec == NULL || !(vec->sv_flags & SV_RESETHAND))
#endif
{
struct sigaction new, *n;
if (vec == NULL)
n = NULL;
else
{
__sighandler_t handler;
unsigned int mask;
unsigned int sv_flags;
unsigned int sa_flags;
handler = vec->sv_handler;
mask = vec->sv_mask;
sv_flags = vec->sv_flags;
sa_flags = 0;
if (sv_flags & SV_ONSTACK)
{
#ifdef SA_ONSTACK
sa_flags |= SA_ONSTACK;
#else
__set_errno (ENOSYS);
return -1;
#endif
}
#ifdef SA_RESTART
if (!(sv_flags & SV_INTERRUPT))
sa_flags |= SA_RESTART;
#endif
#ifdef SA_RESETHAND
if (sv_flags & SV_RESETHAND)
sa_flags |= SA_RESETHAND;
#endif
n = &new;
new.sa_handler = handler;
if (sigset_set_old_mask (&new.sa_mask, mask) < 0)
return -1;
new.sa_flags = sa_flags;
}
if (__sigaction (sig, n, &old) < 0)
return -1;
}
#ifndef SA_RESETHAND
else
{
__sighandler_t handler;
unsigned int mask;
struct sigvec_wrapper_data *data;
struct sigaction wrapper;
handler = vec->sv_handler;
mask = (unsigned int)vec->sv_mask;
data = &sigvec_wrapper_data[sig];
wrapper.sa_handler = sigvec_wrapper_handler;
/* FIXME: should we set wrapper.sa_mask, wrapper.sa_flags?? */
data->sw_handler = handler;
data->sw_mask = mask;
if (__sigaction (sig, &wrapper, &old) < 0)
return -1;
}
#endif
if (ovec != NULL)
{
__sighandler_t handler;
unsigned int sv_flags;
unsigned int sa_flags;
unsigned int mask;
handler = old.sa_handler;
sv_flags = 0;
sa_flags = old.sa_flags;
#ifndef SA_RESETHAND
if (handler == sigvec_wrapper_handler)
{
handler = sigvec_wrapper_data[sig].sw_handler;
/* should we use data->sw_mask?? */
sv_flags |= SV_RESETHAND;
}
#else
if (sa_flags & SA_RESETHAND)
sv_flags |= SV_RESETHAND;
#endif
mask = sigset_get_old_mask (&old.sa_mask);
#ifdef SA_ONSTACK
if (sa_flags & SA_ONSTACK)
sv_flags |= SV_ONSTACK;
#endif
#ifdef SA_RESTART
if (!(sa_flags & SA_RESTART))
#endif
sv_flags |= SV_INTERRUPT;
ovec->sv_handler = handler;
ovec->sv_mask = (int)mask;
ovec->sv_flags = (int)sv_flags;
}
return 0;
}
weak_alias (__sigvec, sigvec)
#ifndef SA_RESETHAND
static void
sigvec_wrapper_handler (sig)
int sig;
{
struct sigvec_wrapper_data *data;
struct sigaction act;
int save;
__sighandler_t handler;
data = &sigvec_wrapper_data[sig];
act.sa_handler = SIG_DFL;
act.sa_flags = 0;
sigset_set_old_mask (&act.sa_mask, data->sw_mask);
handler = data->sw_handler;
save = errno;
(void) __sigaction (sig, &act, (struct sigaction *) NULL);
__set_errno (save);
(*handler) (sig);
}
#endif