1 /* $NetBSD: tstp.c,v 1.40 2013/10/15 13:00:52 christos Exp $ */
2
3 /*
4 * Copyright (c) 1981, 1993, 1994
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33 #ifndef lint
34 #if 0
35 static char sccsid[] = "@(#)tstp.c 8.3 (Berkeley) 5/4/94";
36 #else
37 __RCSID("$NetBSD: tstp.c,v 1.40 2013/10/15 13:00:52 christos Exp $");
38 #endif
39 #endif /* not lint */
40
41 #include <sys/ioctl.h>
42
43 #include <errno.h>
44 #include <signal.h>
45 #include <termios.h>
46 #include <unistd.h>
47
48 #include "curses.h"
49 #include "curses_private.h"
50
51 static int tstp_set = 0;
52 static int winch_set = 0;
53
54 static void (*otstpfn)
55 __P((int)) = SIG_DFL;
56
57 static struct sigaction owsa;
58 #ifndef TCSASOFT
59 #define TCSASOFT 0
60 #endif
61
62 /*
63 * stop_signal_handler --
64 * Handle stop signals.
65 */
66 void
__stop_signal_handler(int signo)67 __stop_signal_handler(/*ARGSUSED*/int signo)
68 {
69 sigset_t oset, set;
70
71 /*
72 * Block window change and timer signals. The latter is because
73 * applications use timers to decide when to repaint the screen.
74 */
75 (void) sigemptyset(&set);
76 (void) sigaddset(&set, SIGALRM);
77 (void) sigaddset(&set, SIGWINCH);
78 (void) sigprocmask(SIG_BLOCK, &set, &oset);
79
80 /*
81 * End the window, which also resets the terminal state to the
82 * original modes.
83 */
84 __stopwin();
85
86 /* Unblock SIGTSTP. */
87 (void) sigemptyset(&set);
88 (void) sigaddset(&set, SIGTSTP);
89 (void) sigprocmask(SIG_UNBLOCK, &set, NULL);
90
91 /* Stop ourselves. */
92 (void) kill(0, SIGTSTP);
93
94 /* Time passes ... */
95
96 /* restart things */
97 __restartwin();
98
99 /* Reset the signals. */
100 (void) sigprocmask(SIG_SETMASK, &oset, NULL);
101 }
102
103 /*
104 * Set the TSTP handler.
105 */
106 void
__set_stophandler(void)107 __set_stophandler(void)
108 {
109 #ifdef DEBUG
110 __CTRACE(__CTRACE_MISC, "__set_stophandler: %d\n", tstp_set);
111 #endif
112 if (!tstp_set) {
113 otstpfn = signal(SIGTSTP, __stop_signal_handler);
114 tstp_set = 1;
115 }
116 }
117
118 /*
119 * Restore the TSTP handler.
120 */
121 void
__restore_stophandler(void)122 __restore_stophandler(void)
123 {
124 #ifdef DEBUG
125 __CTRACE(__CTRACE_MISC, "__restore_stophandler: %d\n", tstp_set);
126 #endif
127 if (tstp_set) {
128 (void) signal(SIGTSTP, otstpfn);
129 tstp_set = 0;
130 }
131 }
132
133 /*
134 * winch_signal_handler --
135 * Handle winch signals by pushing KEY_RESIZE into the input stream.
136 */
137 void
__winch_signal_handler(int signo)138 __winch_signal_handler(/*ARGSUSED*/int signo)
139 {
140 struct winsize win;
141
142 if (ioctl(fileno(_cursesi_screen->outfd), TIOCGWINSZ, &win) != -1 &&
143 win.ws_row != 0 && win.ws_col != 0) {
144 LINES = win.ws_row;
145 COLS = win.ws_col;
146 }
147 /*
148 * If there was a previous handler, call that,
149 * otherwise tell getch() to send KEY_RESIZE.
150 */
151 if (owsa.sa_handler != NULL)
152 owsa.sa_handler(signo);
153 else
154 _cursesi_screen->resized = 1;
155 }
156
157 /*
158 * Set the WINCH handler.
159 */
160 void
__set_winchhandler(void)161 __set_winchhandler(void)
162 {
163 #ifdef DEBUG
164 __CTRACE(__CTRACE_MISC, "__set_winchhandler: %d\n", winch_set);
165 #endif
166 if (!winch_set) {
167 struct sigaction sa;
168
169 sa.sa_handler = __winch_signal_handler;
170 sa.sa_flags = 0;
171 sigemptyset(&sa.sa_mask);
172 sigaction(SIGWINCH, &sa, &owsa);
173 winch_set = 1;
174 #ifdef DEBUG
175 __CTRACE(__CTRACE_MISC,
176 "__set_winchhandler: owsa.sa_handler=%p\n",
177 owsa.sa_handler);
178 #endif
179 }
180 }
181
182 /*
183 * Restore the WINCH handler.
184 */
185 void
__restore_winchhandler(void)186 __restore_winchhandler(void)
187 {
188 #ifdef DEBUG
189 __CTRACE(__CTRACE_MISC, "__restore_winchhandler: %d\n", winch_set);
190 #endif
191 if (winch_set > 0) {
192 struct sigaction cwsa;
193
194 sigaction(SIGWINCH, NULL, &cwsa);
195 if (cwsa.sa_handler == owsa.sa_handler) {
196 sigaction(SIGWINCH, &owsa, NULL);
197 winch_set = 0;
198 } else {
199 /*
200 * We're now using the programs WINCH handler,
201 * so don't restore the previous one.
202 */
203 winch_set = -1;
204 #ifdef DEBUG
205 __CTRACE(__CTRACE_MISC, "cwsa.sa_handler = %p\n",
206 cwsa.sa_handler);
207 #endif
208 }
209 }
210 }
211
212 /* To allow both SIGTSTP and endwin() to come back nicely, we provide
213 the following routines. */
214
215 int
__stopwin(void)216 __stopwin(void)
217 {
218 #ifdef DEBUG
219 __CTRACE(__CTRACE_MISC, "__stopwin\n");
220 #endif
221 if (_cursesi_screen->endwin)
222 return OK;
223
224 /* Get the current terminal state (which the user may have changed). */
225 (void) tcgetattr(fileno(_cursesi_screen->infd),
226 &_cursesi_screen->save_termios);
227
228 __restore_stophandler();
229 __restore_winchhandler();
230
231 if (curscr != NULL) {
232 __unsetattr(0);
233 __mvcur((int) curscr->cury, (int) curscr->curx,
234 (int) curscr->maxy - 1, 0, 0);
235 }
236
237 if (meta_on != NULL)
238 (void) tputs(meta_on, 0, __cputchar);
239
240 if ((curscr != NULL) && (curscr->flags & __KEYPAD))
241 (void) tputs(keypad_local, 0, __cputchar);
242 (void) tputs(cursor_normal, 0, __cputchar);
243 (void) tputs(exit_ca_mode, 0, __cputchar);
244 (void) fflush(_cursesi_screen->outfd);
245 (void) setvbuf(_cursesi_screen->outfd, NULL, _IOLBF, (size_t) 0);
246
247 _cursesi_screen->endwin = 1;
248
249 return tcsetattr(fileno(_cursesi_screen->infd), TCSASOFT | TCSADRAIN,
250 &_cursesi_screen->orig_termios) ? ERR : OK;
251 }
252
253
254 void
__restartwin(void)255 __restartwin(void)
256 {
257 struct winsize win;
258 int nlines, ncols;
259
260 #ifdef DEBUG
261 __CTRACE(__CTRACE_MISC, "__restartwin\n");
262 #endif
263 if (!_cursesi_screen->endwin)
264 return;
265
266 /* Reset the curses SIGTSTP and SIGWINCH signal handlers. */
267 __set_stophandler();
268 __set_winchhandler();
269
270 /*
271 * Check to see if the window size has changed.
272 * If the application didn't update LINES and COLS,
273 * set the * resized flag to tell getch() to push KEY_RESIZE.
274 * Update curscr (which also updates __virtscr) and stdscr
275 * to match the new size.
276 */
277 if (ioctl(fileno(_cursesi_screen->outfd), TIOCGWINSZ, &win) != -1 &&
278 win.ws_row != 0 && win.ws_col != 0) {
279 if (win.ws_row != LINES) {
280 LINES = win.ws_row;
281 _cursesi_screen->resized = 1;
282 }
283 if (win.ws_col != COLS) {
284 COLS = win.ws_col;
285 _cursesi_screen->resized = 1;
286 }
287 }
288 /*
289 * We need to make local copies of LINES and COLS, otherwise we
290 * could lose if they are changed between wresize() calls.
291 */
292 nlines = LINES;
293 ncols = COLS;
294 if (curscr->maxy != nlines || curscr->maxx != ncols)
295 wresize(curscr, nlines, ncols);
296 if (stdscr->maxy != nlines || stdscr->maxx != ncols)
297 wresize(stdscr, nlines, ncols);
298
299 /* save the new "default" terminal state */
300 (void) tcgetattr(fileno(_cursesi_screen->infd),
301 &_cursesi_screen->orig_termios);
302
303 /* Reset the terminal state to the mode just before we stopped. */
304 (void) tcsetattr(fileno(_cursesi_screen->infd), TCSASOFT | TCSADRAIN,
305 &_cursesi_screen->save_termios);
306
307 /* Restore colours */
308 __restore_colors();
309
310 /* Reset meta */
311 __restore_meta_state();
312
313 /* Restart the screen. */
314 __startwin(_cursesi_screen);
315
316 /* Reset cursor visibility */
317 __restore_cursor_vis();
318
319 /* Repaint the screen. */
320 wrefresh(curscr);
321 }
322
323 int
def_prog_mode(void)324 def_prog_mode(void)
325 {
326 if (_cursesi_screen->endwin)
327 return ERR;
328
329 return tcgetattr(fileno(_cursesi_screen->infd),
330 &_cursesi_screen->save_termios) ? ERR : OK;
331 }
332
333 int
reset_prog_mode(void)334 reset_prog_mode(void)
335 {
336
337 return tcsetattr(fileno(_cursesi_screen->infd), TCSASOFT | TCSADRAIN,
338 &_cursesi_screen->save_termios) ? ERR : OK;
339 }
340
341 int
def_shell_mode(void)342 def_shell_mode(void)
343 {
344 return tcgetattr(fileno(_cursesi_screen->infd),
345 &_cursesi_screen->orig_termios) ? ERR : OK;
346 }
347
348 int
reset_shell_mode(void)349 reset_shell_mode(void)
350 {
351 return __stopwin();
352 }
353