freebsd-skq/20150505/sigcompat.c
2015-05-10 20:02:26 +00:00

326 lines
8.5 KiB
C

/*
* NAME:
* sigcompat - BSD compat signals via POSIX
*
* SYNOPSIS:
* void (*signal(int "sig", void (*"handler")(int)))(int);
* int sigsetmask(int "mask");
* int sigblock(int "mask");
* int sigpause(int "mask");
* int sigvec(int "signo", struct sigvec *"sv", struct sigvec *"osv");
*
* DESCRIPTION:
* These implement the old BSD routines via the POSIX equivalents.
* This module can be used to provide the missing routines, or if
* 'FORCE_POSIX_SIGNALS' is defined, force use of these.
*
* Note that signal() is identical to my Signal() routine except
* for checking for recursion. Within libsig, signal() just
* calls Signal().
*
* BUGS:
* This package assumes POSIX signal handling is available and
* NOT implemeneted using these routines. To be safe, we check
* for recursion and abort(3) if detected.
*
* Sadly, on some systems, sigset_t is an array, and we cannot
* test for this via #if sizeof(sigset_t) ..., so unless
* 'SIGSET_T_INT' is defined, we have to assume the worst and use
* memcpy(3) to handle args and return values.
*
* HISTORY:
* These routines originate from BSD, and are derrived from the
* NetBSD 1.1 implementation. They have been seriously hacked to
* make them portable to other systems.
*
* AUTHOR:
* Simon J. Gerraty <sjg@crufty.net>
*/
/*
* @(#)Copyright (c) 1994, Simon J. Gerraty.
*
* This is free software. It comes with NO WARRANTY.
* Permission to use, modify and distribute this source code
* is granted subject to the following conditions.
* 1/ that the above copyright notice and this notice
* are preserved in all copies and that due credit be given
* to the author.
* 2/ that any changes to this code are clearly commented
* as such so that the author does not get blamed for bugs
* other than his own.
*
* Please send copies of changes and bug-fixes to:
* sjg@crufty.net
*/
/*
* Copyright (c) 1989 The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <signal.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#if defined(sun) && !(defined(__svr4__) || defined(__SVR4))
# define NO_SIGCOMPAT
#endif
#if defined(__MINT__)
# define NO_SIGCOMPAT
#endif
#if !defined(NO_SIGCOMPAT) && (defined(HAVE_SIGACTION) || defined(SA_NOCLDSTOP))
#if defined(LIBC_SCCS) && !defined(lint)
/*static char *sccsid = "from: @(#)sigcompat.c 5.3 (Berkeley) 2/24/91";*/
static char *rcsid = "$Id: sigcompat.c,v 1.23 2011/02/14 00:07:11 sjg Exp $";
#endif /* LIBC_SCCS and not lint */
#undef signal
#include <stdio.h>
#include <string.h>
#include <sys/param.h>
#include <sys/cdefs.h>
#include "assert.h"
#ifndef ASSERT
# define ASSERT assert
#endif
#ifdef NDEBUG
# define _DBUG(x)
#else
# define _DBUG(x) x
#endif
#ifndef SA_RESTART
# define SA_RESTART 2
#endif
#ifndef SV_INTERRUPT
# define SV_INTERRUPT SA_RESTART
#endif
#ifndef MASK_T
# if defined(__hpux__) || defined(__hpux)
# define MASK_T long
# else
# define MASK_T int
# endif
#endif
/* I just hate HPsUX */
#if (defined(__HPUX_VERSION) && __HPUX_VERSION > 9) || defined(__hpux)
# define PAUSE_MASK_T int
#else
# define PAUSE_MASK_T MASK_T
#endif
#ifndef SIG_HDLR
# define SIG_HDLR void
#endif
#ifdef FORCE_POSIX_SIGNALS
#if !(defined(libsig) || defined(libsjg))
/*
* This little block is almost identical to Signal(),
* and make this module standalone.
* We don't use it in libsig by default, as some apps might use both
* and expect _SignalFlags to be used by both.
*/
#ifndef SIGNAL_FLAGS
# define SIGNAL_FLAGS 0 /* no auto-restart */
#endif
int _signalFlags = SIGNAL_FLAGS;
SIG_HDLR(*signal(int sig, SIG_HDLR(*handler)(int)))(int)
{
_DBUG(static int depth_signal = 0);
struct sigaction act, oact;
int n;
_DBUG(++depth_signal);
ASSERT(depth_signal < 2);
act.sa_handler = handler;
sigemptyset(&act.sa_mask);
act.sa_flags = _signalFlags;
n = sigaction(sig, &act, &oact);
_DBUG(--depth_signal);
if (n < 0)
return (SIG_ERR);
return (oact.sa_handler);
}
#else
SIG_HDLR(*signal(int sig, SIG_HDLR(*handler)(int)))(int)
{
extern SIG_HDLR(*Signal(int, void (*)(int)))(int);
_DBUG(static int depth_signal = 0);
SIG_HDLR(*old) __P((int));
_DBUG(++depth_signal);
ASSERT(depth_signal < 2);
old = Signal(sig, handler);
_DBUG(--depth_signal);
return old;
}
#endif
#endif
/*
* on some systems, sigset_t is an array...
* it would be nicer if we could do
* #if sizeof(sigset_t) > sizeof(MASK_T)
*/
#ifdef SIGSET_T_INT
# define ss2m(ss) (MASK_T) *(ss)
# define m2ss(ss, m) *ss = (sigset_t) *(m)
#else
static MASK_T
ss2m(sigset_t *ss)
{
MASK_T ma[(sizeof(sigset_t) / sizeof(MASK_T)) + 1];
memcpy((char *) ma, (char *) ss, sizeof(sigset_t));
return ma[0];
}
static void
m2ss(sigset_t *ss, MASK_T *m)
{
if (sizeof(sigset_t) > sizeof(MASK_T))
memset((char *) ss, 0, sizeof(sigset_t));
memcpy((char *) ss, (char *) m, sizeof(MASK_T));
}
#endif
#if !defined(HAVE_SIGSETMASK) || defined(FORCE_POSIX_SIGNALS)
MASK_T
sigsetmask(MASK_T mask)
{
_DBUG(static int depth_sigsetmask = 0);
sigset_t m, omask;
int n;
_DBUG(++depth_sigsetmask);
ASSERT(depth_sigsetmask < 2);
m2ss(&m, &mask);
n = sigprocmask(SIG_SETMASK, (sigset_t *) & m, (sigset_t *) & omask);
_DBUG(--depth_sigsetmask);
if (n)
return (n);
return ss2m(&omask);
}
MASK_T
sigblock(MASK_T mask)
{
_DBUG(static int depth_sigblock = 0);
sigset_t m, omask;
int n;
_DBUG(++depth_sigblock);
ASSERT(depth_sigblock < 2);
if (mask)
m2ss(&m, &mask);
n = sigprocmask(SIG_BLOCK, (sigset_t *) ((mask) ? &m : 0), (sigset_t *) & omask);
_DBUG(--depth_sigblock);
if (n)
return (n);
return ss2m(&omask);
}
#undef sigpause /* Linux at least */
PAUSE_MASK_T
sigpause(PAUSE_MASK_T mask)
{
_DBUG(static int depth_sigpause = 0);
sigset_t m;
PAUSE_MASK_T n;
_DBUG(++depth_sigpause);
ASSERT(depth_sigpause < 2);
m2ss(&m, &mask);
n = sigsuspend(&m);
_DBUG(--depth_sigpause);
return n;
}
#endif
#if defined(HAVE_SIGVEC) && defined(FORCE_POSIX_SIGNALS)
int
sigvec(int signo, struct sigvec *sv, struct sigvec *osv)
{
_DBUG(static int depth_sigvec = 0);
int ret;
struct sigvec nsv;
_DBUG(++depth_sigvec);
ASSERT(depth_sigvec < 2);
if (sv) {
nsv = *sv;
nsv.sv_flags ^= SV_INTERRUPT; /* !SA_INTERRUPT */
}
ret = sigaction(signo, sv ? (struct sigaction *) & nsv : NULL,
(struct sigaction *) osv);
_DBUG(--depth_sigvec);
if (ret == 0 && osv)
osv->sv_flags ^= SV_INTERRUPT; /* !SA_INTERRUPT */
return (ret);
}
#endif
#ifdef MAIN
# ifndef sigmask
# define sigmask(n) ((unsigned int)1 << (((n) - 1) & (32 - 1)))
# endif
int
main(int argc, char *argv[])
{
MASK_T old = 0;
printf("expect: old=0,old=2\n");
fflush(stdout);
signal(SIGQUIT, SIG_IGN);
old = sigblock(sigmask(SIGINT));
printf("old=%d,", old);
old = sigsetmask(sigmask(SIGALRM));
printf("old=%d\n", old);
}
#endif
#endif