262 lines
4.7 KiB
C
262 lines
4.7 KiB
C
/*
|
|
* Copyright (C) 1984-2023 Mark Nudelman
|
|
*
|
|
* You may distribute under the terms of either the GNU General Public
|
|
* License or the Less License, as specified in the README file.
|
|
*
|
|
* For more information, see the README file.
|
|
*/
|
|
|
|
|
|
/*
|
|
* 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;
|
|
extern int quit_on_intr;
|
|
extern int secure;
|
|
extern long jump_sline_fraction;
|
|
|
|
/*
|
|
* Interrupt signal handler.
|
|
*/
|
|
#if MSDOS_COMPILER!=WIN32C
|
|
/* ARGSUSED*/
|
|
static RETSIGTYPE u_interrupt(int type)
|
|
{
|
|
bell();
|
|
#if OS2
|
|
LSIGNAL(SIGINT, SIG_ACK);
|
|
#endif
|
|
LSIGNAL(SIGINT, u_interrupt);
|
|
sigs |= S_INTERRUPT;
|
|
#if MSDOS_COMPILER==DJGPPC
|
|
/*
|
|
* If a keyboard has been hit, it must be Ctrl-C
|
|
* (as opposed to Ctrl-Break), so consume it.
|
|
* (Otherwise, Less will beep when it sees Ctrl-C from keyboard.)
|
|
*/
|
|
if (kbhit())
|
|
getkey();
|
|
#endif
|
|
#if HILITE_SEARCH
|
|
set_filter_pattern(NULL, 0);
|
|
#endif
|
|
if (reading)
|
|
intread(); /* May longjmp */
|
|
}
|
|
#endif
|
|
|
|
#ifdef SIGTSTP
|
|
/*
|
|
* "Stop" (^Z) signal handler.
|
|
*/
|
|
/* ARGSUSED*/
|
|
static RETSIGTYPE stop(int type)
|
|
{
|
|
LSIGNAL(SIGTSTP, stop);
|
|
sigs |= S_STOP;
|
|
if (reading)
|
|
intread();
|
|
}
|
|
#endif
|
|
|
|
#undef SIG_LESSWINDOW
|
|
#ifdef SIGWINCH
|
|
#define SIG_LESSWINDOW SIGWINCH
|
|
#else
|
|
#ifdef SIGWIND
|
|
#define SIG_LESSWINDOW SIGWIND
|
|
#endif
|
|
#endif
|
|
|
|
#ifdef SIG_LESSWINDOW
|
|
/*
|
|
* "Window" change handler
|
|
*/
|
|
/* ARGSUSED*/
|
|
public RETSIGTYPE winch(int type)
|
|
{
|
|
LSIGNAL(SIG_LESSWINDOW, winch);
|
|
sigs |= S_WINCH;
|
|
if (reading)
|
|
intread();
|
|
}
|
|
#endif
|
|
|
|
#if MSDOS_COMPILER==WIN32C
|
|
/*
|
|
* Handle CTRL-C and CTRL-BREAK keys.
|
|
*/
|
|
#define WIN32_LEAN_AND_MEAN
|
|
#include <windows.h>
|
|
|
|
static BOOL WINAPI wbreak_handler(DWORD dwCtrlType)
|
|
{
|
|
switch (dwCtrlType)
|
|
{
|
|
case CTRL_C_EVENT:
|
|
case CTRL_BREAK_EVENT:
|
|
sigs |= S_INTERRUPT;
|
|
#if HILITE_SEARCH
|
|
set_filter_pattern(NULL, 0);
|
|
#endif
|
|
return (TRUE);
|
|
default:
|
|
break;
|
|
}
|
|
return (FALSE);
|
|
}
|
|
#endif
|
|
|
|
static RETSIGTYPE terminate(int type)
|
|
{
|
|
quit(15);
|
|
}
|
|
|
|
/*
|
|
* Set up the signal handlers.
|
|
*/
|
|
public void init_signals(int on)
|
|
{
|
|
if (on)
|
|
{
|
|
/*
|
|
* Set signal handlers.
|
|
*/
|
|
#if MSDOS_COMPILER==WIN32C
|
|
SetConsoleCtrlHandler(wbreak_handler, TRUE);
|
|
#else
|
|
(void) LSIGNAL(SIGINT, u_interrupt);
|
|
#endif
|
|
#ifdef SIGTSTP
|
|
(void) LSIGNAL(SIGTSTP, secure ? SIG_IGN : stop);
|
|
#endif
|
|
#ifdef SIGWINCH
|
|
(void) LSIGNAL(SIGWINCH, winch);
|
|
#endif
|
|
#ifdef SIGWIND
|
|
(void) LSIGNAL(SIGWIND, winch);
|
|
#endif
|
|
#ifdef SIGQUIT
|
|
(void) LSIGNAL(SIGQUIT, SIG_IGN);
|
|
#endif
|
|
#ifdef SIGTERM
|
|
(void) LSIGNAL(SIGTERM, terminate);
|
|
#endif
|
|
} else
|
|
{
|
|
/*
|
|
* Restore signals to defaults.
|
|
*/
|
|
#if MSDOS_COMPILER==WIN32C
|
|
SetConsoleCtrlHandler(wbreak_handler, FALSE);
|
|
#else
|
|
(void) LSIGNAL(SIGINT, SIG_DFL);
|
|
#endif
|
|
#ifdef SIGTSTP
|
|
(void) LSIGNAL(SIGTSTP, SIG_DFL);
|
|
#endif
|
|
#ifdef SIGWINCH
|
|
(void) LSIGNAL(SIGWINCH, SIG_IGN);
|
|
#endif
|
|
#ifdef SIGWIND
|
|
(void) LSIGNAL(SIGWIND, SIG_IGN);
|
|
#endif
|
|
#ifdef SIGQUIT
|
|
(void) LSIGNAL(SIGQUIT, SIG_DFL);
|
|
#endif
|
|
#ifdef SIGTERM
|
|
(void) LSIGNAL(SIGTERM, SIG_DFL);
|
|
#endif
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Process any signals we have received.
|
|
* A received signal cause a bit to be set in "sigs".
|
|
*/
|
|
public void psignals(void)
|
|
{
|
|
int tsignals;
|
|
|
|
if ((tsignals = sigs) == 0)
|
|
return;
|
|
sigs = 0;
|
|
|
|
#ifdef SIGTSTP
|
|
if (tsignals & S_STOP)
|
|
{
|
|
/*
|
|
* Clean up the terminal.
|
|
*/
|
|
#ifdef SIGTTOU
|
|
LSIGNAL(SIGTTOU, SIG_IGN);
|
|
#endif
|
|
clear_bot();
|
|
deinit();
|
|
flush();
|
|
raw_mode(0);
|
|
#ifdef SIGTTOU
|
|
LSIGNAL(SIGTTOU, SIG_DFL);
|
|
#endif
|
|
LSIGNAL(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.
|
|
*/
|
|
LSIGNAL(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;
|
|
calc_jump_sline();
|
|
calc_shift_count();
|
|
}
|
|
screen_trashed = 1;
|
|
}
|
|
#endif
|
|
if (tsignals & S_INTERRUPT)
|
|
{
|
|
if (quit_on_intr)
|
|
quit(QUIT_INTERRUPT);
|
|
}
|
|
}
|