NetBSD/lib/libcurses/tstp.c
roy 501d84b3ab curses: don't optimize stdout buffer for non BSD platforms
The way BSD setvbuf works is not portable and should not be relied on.
This is only important if curses is started, stopped and started in the
same session which is how portable applications handle terminal resizing.
2018-10-18 07:53:13 +00:00

369 lines
8.4 KiB
C

/* $NetBSD: tstp.c,v 1.44 2018/10/18 07:53:13 roy Exp $ */
/*
* Copyright (c) 1981, 1993, 1994
* 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. 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 <sys/cdefs.h>
#ifndef lint
#if 0
static char sccsid[] = "@(#)tstp.c 8.3 (Berkeley) 5/4/94";
#else
__RCSID("$NetBSD: tstp.c,v 1.44 2018/10/18 07:53:13 roy Exp $");
#endif
#endif /* not lint */
#include <sys/ioctl.h>
#include <sys/param.h>
#include <errno.h>
#include <signal.h>
#include <termios.h>
#include <unistd.h>
#include "curses.h"
#include "curses_private.h"
static int tstp_set;
static int winch_set;
static void (*otstpfn)(int) = SIG_DFL;
static struct sigaction owsa;
#ifndef TCSASOFT
#define TCSASOFT 0
#endif
/*
* stop_signal_handler --
* Handle stop signals.
*/
void
__stop_signal_handler(/*ARGSUSED*/int signo)
{
sigset_t oset, set;
/*
* Block window change and timer signals. The latter is because
* applications use timers to decide when to repaint the screen.
*/
(void)sigemptyset(&set);
(void)sigaddset(&set, SIGALRM);
(void)sigaddset(&set, SIGWINCH);
(void)sigprocmask(SIG_BLOCK, &set, &oset);
/*
* End the window, which also resets the terminal state to the
* original modes.
*/
__stopwin();
/* Unblock SIGTSTP. */
(void)sigemptyset(&set);
(void)sigaddset(&set, SIGTSTP);
(void)sigprocmask(SIG_UNBLOCK, &set, NULL);
/* Stop ourselves. */
(void)kill(0, SIGTSTP);
/* Time passes ... */
/* restart things */
__restartwin();
/* Reset the signals. */
(void)sigprocmask(SIG_SETMASK, &oset, NULL);
}
/*
* Set the TSTP handler.
*/
void
__set_stophandler(void)
{
#ifdef DEBUG
__CTRACE(__CTRACE_MISC, "__set_stophandler: %d\n", tstp_set);
#endif
if (!tstp_set) {
otstpfn = signal(SIGTSTP, __stop_signal_handler);
tstp_set = 1;
}
}
/*
* Restore the TSTP handler.
*/
void
__restore_stophandler(void)
{
#ifdef DEBUG
__CTRACE(__CTRACE_MISC, "__restore_stophandler: %d\n", tstp_set);
#endif
if (tstp_set) {
(void)signal(SIGTSTP, otstpfn);
tstp_set = 0;
}
}
/*
* winch_signal_handler --
* Handle winch signals by pushing KEY_RESIZE into the input stream.
*/
void
__winch_signal_handler(/*ARGSUSED*/int signo)
{
struct winsize win;
if (ioctl(fileno(_cursesi_screen->outfd), TIOCGWINSZ, &win) != -1 &&
win.ws_row != 0 && win.ws_col != 0)
{
LINES = win.ws_row;
COLS = win.ws_col;
}
/*
* If there was a previous handler, call that,
* otherwise tell getch() to send KEY_RESIZE.
*/
if (owsa.sa_handler != SIG_DFL &&
owsa.sa_handler != SIG_IGN &&
owsa.sa_handler != SIG_ERR &&
owsa.sa_handler != SIG_HOLD)
owsa.sa_handler(signo);
else
_cursesi_screen->resized = 1;
}
/*
* Set the WINCH handler.
*/
void
__set_winchhandler(void)
{
#ifdef DEBUG
__CTRACE(__CTRACE_MISC, "__set_winchhandler: %d\n", winch_set);
#endif
if (!winch_set) {
struct sigaction sa;
sa.sa_handler = __winch_signal_handler;
sa.sa_flags = 0;
sigemptyset(&sa.sa_mask);
sigaction(SIGWINCH, &sa, &owsa);
winch_set = 1;
#ifdef DEBUG
__CTRACE(__CTRACE_MISC,
"__set_winchhandler: owsa.sa_handler=%p\n",
owsa.sa_handler);
#endif
}
}
/*
* Restore the WINCH handler.
*/
void
__restore_winchhandler(void)
{
#ifdef DEBUG
__CTRACE(__CTRACE_MISC, "__restore_winchhandler: %d\n", winch_set);
#endif
if (winch_set > 0) {
struct sigaction cwsa;
sigaction(SIGWINCH, NULL, &cwsa);
if (cwsa.sa_handler == owsa.sa_handler) {
sigaction(SIGWINCH, &owsa, NULL);
winch_set = 0;
} else {
/*
* We're now using the programs WINCH handler,
* so don't restore the previous one.
*/
winch_set = -1;
#ifdef DEBUG
__CTRACE(__CTRACE_MISC, "cwsa.sa_handler = %p\n",
cwsa.sa_handler);
#endif
}
}
}
/* To allow both SIGTSTP and endwin() to come back nicely, we provide
the following routines. */
int
__stopwin(void)
{
#ifdef DEBUG
__CTRACE(__CTRACE_MISC, "__stopwin\n");
#endif
if (_cursesi_screen == NULL)
return ERR;
if (_cursesi_screen->endwin)
return OK;
/* Get the current terminal state (which the user may have changed). */
(void)tcgetattr(fileno(_cursesi_screen->infd),
&_cursesi_screen->save_termios);
__restore_stophandler();
__restore_winchhandler();
if (curscr != NULL) {
__unsetattr(0);
__mvcur((int)curscr->cury, (int)curscr->curx,
(int)curscr->maxy - 1, 0, 0);
}
if (meta_on != NULL)
(void)tputs(meta_on, 0, __cputchar);
if ((curscr != NULL) && (curscr->flags & __KEYPAD))
(void)tputs(keypad_local, 0, __cputchar);
(void)tputs(cursor_normal, 0, __cputchar);
(void)tputs(exit_ca_mode, 0, __cputchar);
(void)fflush(_cursesi_screen->outfd);
#ifdef BSD
(void)setvbuf(_cursesi_screen->outfd, NULL, _IOLBF, 0);
#endif
_cursesi_screen->endwin = 1;
return tcsetattr(fileno(_cursesi_screen->infd), TCSASOFT | TCSADRAIN,
&_cursesi_screen->orig_termios) ? ERR : OK;
}
void
__restartwin(void)
{
struct winsize win;
int nlines, ncols;
#ifdef DEBUG
__CTRACE(__CTRACE_MISC, "__restartwin\n");
#endif
if (!_cursesi_screen->endwin)
return;
/* Reset the curses SIGTSTP and SIGWINCH signal handlers. */
__set_stophandler();
__set_winchhandler();
/*
* Check to see if the window size has changed.
* If the application didn't update LINES and COLS,
* set the * resized flag to tell getch() to push KEY_RESIZE.
* Update curscr (which also updates __virtscr) and stdscr
* to match the new size.
*/
if (ioctl(fileno(_cursesi_screen->outfd), TIOCGWINSZ, &win) != -1 &&
win.ws_row != 0 && win.ws_col != 0)
{
if (win.ws_row != LINES) {
LINES = win.ws_row;
_cursesi_screen->resized = 1;
}
if (win.ws_col != COLS) {
COLS = win.ws_col;
_cursesi_screen->resized = 1;
}
}
/*
* We need to make local copies of LINES and COLS, otherwise we
* could lose if they are changed between wresize() calls.
*/
nlines = LINES;
ncols = COLS;
if (curscr->maxy != nlines || curscr->maxx != ncols)
wresize(curscr, nlines, ncols);
if (stdscr->maxy != nlines || stdscr->maxx != ncols)
wresize(stdscr, nlines, ncols);
/* save the new "default" terminal state */
(void)tcgetattr(fileno(_cursesi_screen->infd),
&_cursesi_screen->orig_termios);
/* Reset the terminal state to the mode just before we stopped. */
(void)tcsetattr(fileno(_cursesi_screen->infd), TCSASOFT | TCSADRAIN,
&_cursesi_screen->save_termios);
/* Restore colours */
__restore_colors();
/* Reset meta */
__restore_meta_state();
/* Restart the screen. */
__startwin(_cursesi_screen);
/* Reset cursor visibility */
__restore_cursor_vis();
/* Repaint the screen. */
wrefresh(curscr);
}
int
def_prog_mode(void)
{
if (_cursesi_screen->endwin)
return ERR;
return tcgetattr(fileno(_cursesi_screen->infd),
&_cursesi_screen->save_termios) ? ERR : OK;
}
int
reset_prog_mode(void)
{
return tcsetattr(fileno(_cursesi_screen->infd), TCSASOFT | TCSADRAIN,
&_cursesi_screen->save_termios) ? ERR : OK;
}
int
def_shell_mode(void)
{
return tcgetattr(fileno(_cursesi_screen->infd),
&_cursesi_screen->orig_termios) ? ERR : OK;
}
int
reset_shell_mode(void)
{
return __stopwin();
}