/*      $NetBSD: sig.c,v 1.29 2025/06/14 13:43:50 christos Exp $        */

/*-
* Copyright (c) 1992, 1993
*      The Regents of the University of California.  All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Christos Zoulas of Cornell University.
*
* 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. 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.
*/

#include "config.h"
#if !defined(lint) && !defined(SCCSID)
#if 0
static char sccsid[] = "@(#)sig.c       8.1 (Berkeley) 6/4/93";
#else
__RCSID("$NetBSD: sig.c,v 1.29 2025/06/14 13:43:50 christos Exp $");
#endif
#endif /* not lint && not SCCSID */

/*
* sig.c: Signal handling stuff.
*        our policy is to trap all signals, set a good state
*        and pass the ball to our caller.
*/
#include <errno.h>
#include <stdlib.h>

#include "el.h"
#include "common.h"

static EditLine *sel = NULL;

static const int sighdl[] = {
#define _DO(a)  (a),
       ALLSIGS
#undef  _DO
       - 1
};

static void sig_handler(int);

/* sig_handler():
*      This is the handler called for all signals
*      XXX: we cannot pass any data so we just store the old editline
*      state in a private variable
*/
static void
sig_handler(int signo)
{
       int i, save_errno;
       sigset_t nset, oset;

       save_errno = errno;
       (void) sigemptyset(&nset);
       (void) sigaddset(&nset, signo);
       (void) sigprocmask(SIG_BLOCK, &nset, &oset);

       sel->el_signal->sig_no = signo;

       switch (signo) {
       case SIGCONT:
               tty_rawmode(sel);
               if (ed_redisplay(sel, 0) == CC_REFRESH)
                       re_refresh(sel);
               terminal__flush(sel);
               break;

       case SIGWINCH:
               el_resize(sel);
               break;

       default:
               tty_cookedmode(sel);
               break;
       }

       for (i = 0; sighdl[i] != -1; i++)
               if (signo == sighdl[i])
                       break;

       (void) sigaction(signo, &sel->el_signal->sig_action[i], NULL);
       sel->el_signal->sig_action[i].sa_handler = SIG_ERR;
       sel->el_signal->sig_action[i].sa_flags = 0;
       sigemptyset(&sel->el_signal->sig_action[i].sa_mask);
       (void) sigprocmask(SIG_SETMASK, &oset, NULL);
       (void) raise(signo);
       errno = save_errno;
}


/* sig_init():
*      Initialize all signal stuff
*/
libedit_private int
sig_init(EditLine *el)
{
       size_t i;
       sigset_t *nset, oset;

       el->el_signal = el_malloc(sizeof(*el->el_signal));
       if (el->el_signal == NULL)
               return -1;

       nset = &el->el_signal->sig_set;
       (void) sigemptyset(nset);
#define _DO(a) (void) sigaddset(nset, a);
       ALLSIGS
#undef  _DO
       (void) sigprocmask(SIG_BLOCK, nset, &oset);

       for (i = 0; sighdl[i] != -1; i++) {
               el->el_signal->sig_action[i].sa_handler = SIG_ERR;
               el->el_signal->sig_action[i].sa_flags = 0;
               sigemptyset(&el->el_signal->sig_action[i].sa_mask);
       }

       (void) sigprocmask(SIG_SETMASK, &oset, NULL);

       return 0;
}


/* sig_end():
*      Clear all signal stuff
*/
libedit_private void
sig_end(EditLine *el)
{

       el_free(el->el_signal);
       el->el_signal = NULL;
}


/* sig_set():
*      set all the signal handlers
*/
libedit_private void
sig_set(EditLine *el)
{
       size_t i;
       sigset_t oset;
       struct sigaction osa, nsa;

       nsa.sa_handler = sig_handler;
       nsa.sa_flags = SA_ONSTACK;
       sigemptyset(&nsa.sa_mask);

       sel = el;
       (void) sigprocmask(SIG_BLOCK, &el->el_signal->sig_set, &oset);

       for (i = 0; sighdl[i] != -1; i++) {
               /* This could happen if we get interrupted */
               if (sigaction(sighdl[i], &nsa, &osa) != -1 &&
                   osa.sa_handler != sig_handler)
                       el->el_signal->sig_action[i] = osa;
       }
       (void) sigprocmask(SIG_SETMASK, &oset, NULL);
}


/* sig_clr():
*      clear all the signal handlers
*/
libedit_private void
sig_clr(EditLine *el)
{
       size_t i;
       sigset_t oset;

       (void) sigprocmask(SIG_BLOCK, &el->el_signal->sig_set, &oset);

       for (i = 0; sighdl[i] != -1; i++)
               if (el->el_signal->sig_action[i].sa_handler != SIG_ERR)
                       (void)sigaction(sighdl[i],
                           &el->el_signal->sig_action[i], NULL);

       (void)sigprocmask(SIG_SETMASK, &oset, NULL);
}