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/*
* Copyright (c) 1988 Mark Nudleman
* Copyright (c) 1988, 1993
* 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.
*/
#ifndef lint
static char sccsid[] = "@(#)signal.c 8.1 (Berkeley) 6/6/93";
#endif /* not lint */
/*
* Routines dealing with signals.
*
* A signal usually merely causes a bit to be set in the "signals" word.
* At some convenient time, the mainline code checks to see if any
* signals need processing by calling psignal().
* If we happen to be reading from a file [in iread()] at the time
* the signal is received, we call intread to interrupt the iread.
*/
#include <less.h>
#include <signal.h>
/*
* "sigs" contains bits indicating signals which need to be processed.
*/
int sigs;
#ifdef SIGTSTP
#define S_STOP 02
#endif
#if defined(SIGWINCH) || defined(SIGWIND)
#define S_WINCH 04
#endif
extern int sc_width, sc_height;
extern int screen_trashed;
extern int lnloop;
extern int linenums;
extern int scroll;
extern int reading;
#ifdef SIGTSTP
/*
* "Stop" (^Z) signal handler.
*/
static void
stop()
{
(void)signal(SIGTSTP, stop);
sigs |= S_STOP;
if (reading)
intread();
}
#endif
#ifdef SIGWINCH
/*
* "Window" change handler
*/
void
winch()
{
(void)signal(SIGWINCH, winch);
sigs |= S_WINCH;
if (reading)
intread();
}
#else
#ifdef SIGWIND
/*
* "Window" change handler
*/
winch()
{
(void)signal(SIGWIND, winch);
sigs |= S_WINCH;
if (reading)
intread();
}
#endif
#endif
static void
purgeandquit()
{
purge(); /* purge buffered output */
quit();
}
/*
* Set up the signal handlers.
*/
init_signals(on)
int on;
{
if (on)
{
/*
* Set signal handlers.
*/
(void)signal(SIGINT, purgeandquit);
#ifdef SIGTSTP
(void)signal(SIGTSTP, stop);
#endif
#ifdef SIGWINCH
(void)signal(SIGWINCH, winch);
#else
#ifdef SIGWIND
(void)signal(SIGWIND, winch);
#endif
#endif
} else
{
/*
* Restore signals to defaults.
*/
(void)signal(SIGINT, SIG_DFL);
#ifdef SIGTSTP
(void)signal(SIGTSTP, SIG_DFL);
#endif
#ifdef SIGWINCH
(void)signal(SIGWINCH, SIG_IGN);
#endif
#ifdef SIGWIND
(void)signal(SIGWIND, SIG_IGN);
#endif
}
}
/*
* Process any signals we have received.
* A received signal cause a bit to be set in "sigs".
*/
psignals()
{
register int tsignals;
if ((tsignals = sigs) == 0)
return;
sigs = 0;
#ifdef S_WINCH
if (tsignals & S_WINCH)
{
int old_width, old_height;
/*
* Re-execute get_term() to read the new window size.
*/
old_width = sc_width;
old_height = sc_height;
get_term();
if (sc_width != old_width || sc_height != old_height)
{
scroll = (sc_height + 1) / 2;
screen_trashed = 1;
}
}
#endif
#ifdef SIGTSTP
if (tsignals & S_STOP)
{
/*
* Clean up the terminal.
*/
#ifdef SIGTTOU
(void)signal(SIGTTOU, SIG_IGN);
#endif
lower_left();
clear_eol();
deinit();
(void)flush();
raw_mode(0);
#ifdef SIGTTOU
(void)signal(SIGTTOU, SIG_DFL);
#endif
(void)signal(SIGTSTP, SIG_DFL);
(void)kill(getpid(), SIGTSTP);
/*
* ... Bye bye. ...
* Hopefully we'll be back later and resume here...
* Reset the terminal and arrange to repaint the
* screen when we get back to the main command loop.
*/
(void)signal(SIGTSTP, stop);
raw_mode(1);
init();
screen_trashed = 1;
}
#endif
}
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