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/* $OpenBSD: signal.c,v 1.3 2001/11/19 19:02:14 mpech Exp $ */
/*
* Copyright (c) 1984,1985,1989,1994,1995 Mark Nudelman
* 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 in the documentation and/or other materials provided with
* the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*/
/*
* 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.
*/
public int sigs;
extern int sc_width, sc_height;
extern int screen_trashed;
extern int lnloop;
extern int linenums;
extern int wscroll;
extern int reading;
/*
* Interrupt signal handler.
*/
/* ARGSUSED*/
static RETSIGTYPE
u_interrupt(type)
int type;
{
#if OS2
SIGNAL(SIGINT, SIG_ACK);
#endif
SIGNAL(SIGINT, u_interrupt);
sigs |= S_INTERRUPT;
if (reading)
intread();
}
#ifdef SIGTSTP
/*
* "Stop" (^Z) signal handler.
*/
/* ARGSUSED*/
static RETSIGTYPE
stop(type)
int type;
{
SIGNAL(SIGTSTP, stop);
sigs |= S_STOP;
if (reading)
intread();
}
#endif
#ifdef SIGWINCH
/*
* "Window" change handler
*/
/* ARGSUSED*/
public RETSIGTYPE
winch(type)
int type;
{
SIGNAL(SIGWINCH, winch);
sigs |= S_WINCH;
if (reading)
intread();
}
#else
#ifdef SIGWIND
/*
* "Window" change handler
*/
/* ARGSUSED*/
public RETSIGTYPE
winch(type)
int type;
{
SIGNAL(SIGWIND, winch);
sigs |= S_WINCH;
if (reading)
intread();
}
#endif
#endif
/*
* Set up the signal handlers.
*/
public void
init_signals(on)
int on;
{
if (on)
{
/*
* Set signal handlers.
*/
(void) SIGNAL(SIGINT, u_interrupt);
#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".
*/
public void
psignals()
{
int tsignals;
if ((tsignals = sigs) == 0)
return;
sigs = 0;
#ifdef SIGTSTP
if (tsignals & S_STOP)
{
/*
* Clean up the terminal.
*/
#ifdef SIGTTOU
SIGNAL(SIGTTOU, SIG_IGN);
#endif
clear_bot();
deinit();
flush();
raw_mode(0);
#ifdef SIGTTOU
SIGNAL(SIGTTOU, SIG_DFL);
#endif
SIGNAL(SIGTSTP, SIG_DFL);
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.
*/
SIGNAL(SIGTSTP, stop);
raw_mode(1);
init();
screen_trashed = 1;
tsignals |= S_WINCH;
}
#endif
#ifdef S_WINCH
if (tsignals & S_WINCH)
{
int old_width, old_height;
/*
* Re-execute scrsize() 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)
{
wscroll = (sc_height + 1) / 2;
screen_trashed = 1;
}
}
#endif
if (tsignals & S_INTERRUPT)
{
bell();
/*
* {{ You may wish to replace the bell() with
* error("Interrupt", NULL_PARG); }}
*/
/*
* If we were interrupted while in the "calculating
* line numbers" loop, turn off line numbers.
*/
if (lnloop)
{
lnloop = 0;
if (linenums == 2)
screen_trashed = 1;
linenums = 0;
error("Line numbers turned off", NULL_PARG);
}
}
}
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