1 /****************************************************************************
2  * Copyright (c) 1998-2005,2006 Free Software Foundation, Inc.              *
3  *                                                                          *
4  * Permission is hereby granted, free of charge, to any person obtaining a  *
5  * copy of this software and associated documentation files (the            *
6  * "Software"), to deal in the Software without restriction, including      *
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9  * copies of the Software, and to permit persons to whom the Software is    *
10  * furnished to do so, subject to the following conditions:                 *
11  *                                                                          *
12  * The above copyright notice and this permission notice shall be included  *
13  * in all copies or substantial portions of the Software.                   *
14  *                                                                          *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
16  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
17  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
18  * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
19  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
20  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
21  * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
22  *                                                                          *
23  * Except as contained in this notice, the name(s) of the above copyright   *
24  * holders shall not be used in advertising or otherwise to promote the     *
25  * sale, use or other dealings in this Software without prior written       *
26  * authorization.                                                           *
27  ****************************************************************************/
28 
29 /****************************************************************************
30  *  Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995               *
31  *     and: Eric S. Raymond <esr@snark.thyrsus.com>                         *
32  *     and: Thomas E. Dickey                        1996-on                 *
33  ****************************************************************************/
34 
35 /*
36 **	lib_getch.c
37 **
38 **	The routine getch().
39 **
40 */
41 
42 #include <curses.priv.h>
43 
44 MODULE_ID("$Id: lib_getch.c,v 1.75 2006/03/04 20:06:09 tom Exp $")
45 
46 #include <fifo_defs.h>
47 
48 NCURSES_EXPORT_VAR(int)
49 ESCDELAY = 1000;		/* max interval betw. chars in funkeys, in millisecs */
50 
51 #ifdef NCURSES_WGETCH_EVENTS
52 #define TWAIT_MASK 7
53 #else
54 #define TWAIT_MASK 3
55 #endif
56 
57 /*
58  * Check for mouse activity, returning nonzero if we find any.
59  */
60 static int
61 check_mouse_activity(int delay EVENTLIST_2nd(_nc_eventlist * evl))
62 {
63     int rc;
64 
65 #if USE_SYSMOUSE
66     if ((SP->_mouse_type == M_SYSMOUSE)
67 	&& (SP->_sysmouse_head < SP->_sysmouse_tail)) {
68 	return 2;
69     }
70 #endif
71     rc = _nc_timed_wait(TWAIT_MASK, delay, (int *) 0 EVENTLIST_2nd(evl));
72 #if USE_SYSMOUSE
73     if ((SP->_mouse_type == M_SYSMOUSE)
74 	&& (SP->_sysmouse_head < SP->_sysmouse_tail)
75 	&& (rc == 0)
76 	&& (errno == EINTR)) {
77 	rc |= 2;
78     }
79 #endif
80     return rc;
81 }
82 
83 static NCURSES_INLINE int
84 fifo_peek(void)
85 {
86     int ch = SP->_fifo[peek];
87     TR(TRACE_IEVENT, ("peeking at %d", peek));
88 
89     p_inc();
90     return ch;
91 }
92 
93 static NCURSES_INLINE int
94 fifo_pull(void)
95 {
96     int ch;
97     ch = SP->_fifo[head];
98     TR(TRACE_IEVENT, ("pulling %s from %d", _tracechar(ch), head));
99 
100     if (peek == head) {
101 	h_inc();
102 	peek = head;
103     } else
104 	h_inc();
105 
106 #ifdef TRACE
107     if (_nc_tracing & TRACE_IEVENT)
108 	_nc_fifo_dump();
109 #endif
110     return ch;
111 }
112 
113 static NCURSES_INLINE int
114 fifo_push(EVENTLIST_0th(_nc_eventlist * evl))
115 {
116     int n;
117     int ch = 0;
118     int mask = 0;
119 
120     (void) mask;
121     if (tail == -1)
122 	return ERR;
123 
124 #ifdef HIDE_EINTR
125   again:
126     errno = 0;
127 #endif
128 
129 #ifdef NCURSES_WGETCH_EVENTS
130     if (evl
131 #if USE_GPM_SUPPORT || USE_EMX_MOUSE || USE_SYSMOUSE
132 	|| (SP->_mouse_fd >= 0)
133 #endif
134 	) {
135 	mask = check_mouse_activity(-1 EVENTLIST_2nd(evl));
136     } else
137 	mask = 0;
138 
139     if (mask & 4) {
140 	T(("fifo_push: ungetch KEY_EVENT"));
141 	ungetch(KEY_EVENT);
142 	return KEY_EVENT;
143     }
144 #elif USE_GPM_SUPPORT || USE_EMX_MOUSE || USE_SYSMOUSE
145     if (SP->_mouse_fd >= 0) {
146 	mask = check_mouse_activity(-1 EVENTLIST_2nd(evl));
147     }
148 #endif
149 
150 #if USE_GPM_SUPPORT || USE_EMX_MOUSE
151     if ((SP->_mouse_fd >= 0) && (mask & 2)) {
152 	SP->_mouse_event(SP);
153 	ch = KEY_MOUSE;
154 	n = 1;
155     } else
156 #endif
157 #if USE_SYSMOUSE
158 	if ((SP->_mouse_type == M_SYSMOUSE)
159 	    && (SP->_sysmouse_head < SP->_sysmouse_tail)) {
160 	SP->_mouse_event(SP);
161 	ch = KEY_MOUSE;
162 	n = 1;
163     } else if ((SP->_mouse_type == M_SYSMOUSE)
164 	       && (mask <= 0) && errno == EINTR) {
165 	SP->_mouse_event(SP);
166 	ch = KEY_MOUSE;
167 	n = 1;
168     } else
169 #endif
170     {				/* Can block... */
171 	unsigned char c2 = 0;
172 	n = read(SP->_ifd, &c2, 1);
173 	ch = c2;
174     }
175 
176 #ifdef HIDE_EINTR
177     /*
178      * Under System V curses with non-restarting signals, getch() returns
179      * with value ERR when a handled signal keeps it from completing.
180      * If signals restart system calls, OTOH, the signal is invisible
181      * except to its handler.
182      *
183      * We don't want this difference to show.  This piece of code
184      * tries to make it look like we always have restarting signals.
185      */
186     if (n <= 0 && errno == EINTR)
187 	goto again;
188 #endif
189 
190     if ((n == -1) || (n == 0)) {
191 	TR(TRACE_IEVENT, ("read(%d,&ch,1)=%d, errno=%d", SP->_ifd, n, errno));
192 	ch = ERR;
193     }
194     TR(TRACE_IEVENT, ("read %d characters", n));
195 
196     SP->_fifo[tail] = ch;
197     SP->_fifohold = 0;
198     if (head == -1)
199 	head = peek = tail;
200     t_inc();
201     TR(TRACE_IEVENT, ("pushed %s at %d", _tracechar(ch), tail));
202 #ifdef TRACE
203     if (_nc_tracing & TRACE_IEVENT)
204 	_nc_fifo_dump();
205 #endif
206     return ch;
207 }
208 
209 static NCURSES_INLINE void
210 fifo_clear(void)
211 {
212     memset(SP->_fifo, 0, sizeof(SP->_fifo));
213     head = -1;
214     tail = peek = 0;
215 }
216 
217 static int kgetch(EVENTLIST_0th(_nc_eventlist * evl));
218 
219 #define wgetch_should_refresh(win) (\
220 	(is_wintouched(win) || (win->_flags & _HASMOVED)) \
221 	&& !(win->_flags & _ISPAD))
222 
223 NCURSES_EXPORT(int)
224 _nc_wgetch(WINDOW *win,
225 	   unsigned long *result,
226 	   int use_meta
227 	   EVENTLIST_2nd(_nc_eventlist * evl))
228 {
229     int ch;
230 #ifdef NCURSES_WGETCH_EVENTS
231     long event_delay = -1;
232 #endif
233 
234     T((T_CALLED("_nc_wgetch(%p)"), win));
235 
236     *result = 0;
237     if (win == 0 || SP == 0)
238 	returnCode(ERR);
239 
240     if (cooked_key_in_fifo()) {
241 	if (wgetch_should_refresh(win))
242 	    wrefresh(win);
243 
244 	*result = fifo_pull();
245 	returnCode(OK);
246     }
247 #ifdef NCURSES_WGETCH_EVENTS
248     if (evl && (evl->count == 0))
249 	evl = NULL;
250     event_delay = _nc_eventlist_timeout(evl);
251 #endif
252 
253     /*
254      * Handle cooked mode.  Grab a string from the screen,
255      * stuff its contents in the FIFO queue, and pop off
256      * the first character to return it.
257      */
258     if (head == -1 &&
259 	!SP->_notty &&
260 	!SP->_raw &&
261 	!SP->_cbreak &&
262 	!SP->_called_wgetch) {
263 	char buf[MAXCOLUMNS], *sp;
264 	int rc;
265 
266 	TR(TRACE_IEVENT, ("filling queue in cooked mode"));
267 
268 	SP->_called_wgetch = TRUE;
269 	rc = wgetnstr(win, buf, MAXCOLUMNS);
270 	SP->_called_wgetch = FALSE;
271 
272 	/* ungetch in reverse order */
273 #ifdef NCURSES_WGETCH_EVENTS
274 	if (rc != KEY_EVENT)
275 #endif
276 	    ungetch('\n');
277 	for (sp = buf + strlen(buf); sp > buf; sp--)
278 	    ungetch(sp[-1]);
279 
280 #ifdef NCURSES_WGETCH_EVENTS
281 	/* Return it first */
282 	if (rc == KEY_EVENT) {
283 	    *result = rc;
284 	    returnCode(OK);
285 	}
286 #endif
287 
288 	*result = fifo_pull();
289 	returnCode(OK);
290     }
291 
292     if (win->_use_keypad != SP->_keypad_on)
293 	_nc_keypad(win->_use_keypad);
294 
295     if (wgetch_should_refresh(win))
296 	wrefresh(win);
297 
298     if (!win->_notimeout && (win->_delay >= 0 || SP->_cbreak > 1)) {
299 	if (head == -1) {	/* fifo is empty */
300 	    int delay;
301 	    int rc;
302 
303 	    TR(TRACE_IEVENT, ("timed delay in wgetch()"));
304 	    if (SP->_cbreak > 1)
305 		delay = (SP->_cbreak - 1) * 100;
306 	    else
307 		delay = win->_delay;
308 
309 #ifdef NCURSES_WGETCH_EVENTS
310 	    if (event_delay >= 0 && delay > event_delay)
311 		delay = event_delay;
312 #endif
313 
314 	    TR(TRACE_IEVENT, ("delay is %d milliseconds", delay));
315 
316 	    rc = check_mouse_activity(delay EVENTLIST_2nd(evl));
317 
318 #ifdef NCURSES_WGETCH_EVENTS
319 	    if (rc & 4) {
320 		*result = KEY_EVENT;
321 		returnCode(OK);
322 	    }
323 #endif
324 	    if (!rc)
325 		returnCode(ERR);
326 	}
327 	/* else go on to read data available */
328     }
329 
330     if (win->_use_keypad) {
331 	/*
332 	 * This is tricky.  We only want to get special-key
333 	 * events one at a time.  But we want to accumulate
334 	 * mouse events until either (a) the mouse logic tells
335 	 * us it's picked up a complete gesture, or (b)
336 	 * there's a detectable time lapse after one.
337 	 *
338 	 * Note: if the mouse code starts failing to compose
339 	 * press/release events into clicks, you should probably
340 	 * increase the wait with mouseinterval().
341 	 */
342 	int runcount = 0;
343 	int rc;
344 
345 	do {
346 	    ch = kgetch(EVENTLIST_1st(evl));
347 	    if (ch == KEY_MOUSE) {
348 		++runcount;
349 		if (SP->_mouse_inline(SP))
350 		    break;
351 	    }
352 	    if (SP->_maxclick < 0)
353 		break;
354 	} while
355 	    (ch == KEY_MOUSE
356 	     && (((rc = check_mouse_activity(SP->_maxclick
357 					     EVENTLIST_2nd(evl))) != 0
358 		  && !(rc & 4))
359 		 || !SP->_mouse_parse(runcount)));
360 #ifdef NCURSES_WGETCH_EVENTS
361 	if ((rc & 4) && !ch == KEY_EVENT) {
362 	    ungetch(ch);
363 	    ch = KEY_EVENT;
364 	}
365 #endif
366 	if (runcount > 0 && ch != KEY_MOUSE) {
367 #ifdef NCURSES_WGETCH_EVENTS
368 	    /* mouse event sequence ended by an event, report event */
369 	    if (ch == KEY_EVENT) {
370 		ungetch(KEY_MOUSE);	/* FIXME This interrupts a gesture... */
371 	    } else
372 #endif
373 	    {
374 		/* mouse event sequence ended by keystroke, store keystroke */
375 		ungetch(ch);
376 		ch = KEY_MOUSE;
377 	    }
378 	}
379     } else {
380 	if (head == -1)
381 	    fifo_push(EVENTLIST_1st(evl));
382 	ch = fifo_pull();
383     }
384 
385     if (ch == ERR) {
386 #if USE_SIZECHANGE
387 	if (SP->_sig_winch) {
388 	    _nc_update_screensize();
389 	    /* resizeterm can push KEY_RESIZE */
390 	    if (cooked_key_in_fifo()) {
391 		*result = fifo_pull();
392 		returnCode(*result >= KEY_MIN ? KEY_CODE_YES : OK);
393 	    }
394 	}
395 #endif
396 	returnCode(ERR);
397     }
398 
399     /*
400      * If echo() is in effect, display the printable version of the
401      * key on the screen.  Carriage return and backspace are treated
402      * specially by Solaris curses:
403      *
404      * If carriage return is defined as a function key in the
405      * terminfo, e.g., kent, then Solaris may return either ^J (or ^M
406      * if nonl() is set) or KEY_ENTER depending on the echo() mode.
407      * We echo before translating carriage return based on nonl(),
408      * since the visual result simply moves the cursor to column 0.
409      *
410      * Backspace is a different matter.  Solaris curses does not
411      * translate it to KEY_BACKSPACE if kbs=^H.  This does not depend
412      * on the stty modes, but appears to be a hardcoded special case.
413      * This is a difference from ncurses, which uses the terminfo entry.
414      * However, we provide the same visual result as Solaris, moving the
415      * cursor to the left.
416      */
417     if (SP->_echo && !(win->_flags & _ISPAD)) {
418 	chtype backup = (ch == KEY_BACKSPACE) ? '\b' : ch;
419 	if (backup < KEY_MIN)
420 	    wechochar(win, backup);
421     }
422 
423     /*
424      * Simulate ICRNL mode
425      */
426     if ((ch == '\r') && SP->_nl)
427 	ch = '\n';
428 
429     /* Strip 8th-bit if so desired.  We do this only for characters that
430      * are in the range 128-255, to provide compatibility with terminals
431      * that display only 7-bit characters.  Note that 'ch' may be a
432      * function key at this point, so we mustn't strip _those_.
433      */
434     if (!use_meta)
435 	if ((ch < KEY_MIN) && (ch & 0x80))
436 	    ch &= 0x7f;
437 
438     T(("wgetch returning : %s", _tracechar(ch)));
439 
440     *result = ch;
441     returnCode(ch >= KEY_MIN ? KEY_CODE_YES : OK);
442 }
443 
444 #ifdef NCURSES_WGETCH_EVENTS
445 NCURSES_EXPORT(int)
446 wgetch_events(WINDOW *win, _nc_eventlist * evl)
447 {
448     int code;
449     unsigned long value;
450 
451     T((T_CALLED("wgetch_events(%p,%p)"), win, evl));
452     code = _nc_wgetch(win,
453 		      &value,
454 		      SP->_use_meta
455 		      EVENTLIST_2nd(evl));
456     if (code != ERR)
457 	code = value;
458     returnCode(code);
459 }
460 #endif
461 
462 NCURSES_EXPORT(int)
463 wgetch(WINDOW *win)
464 {
465     int code;
466     unsigned long value;
467 
468     T((T_CALLED("wgetch(%p)"), win));
469     code = _nc_wgetch(win,
470 		      &value,
471 		      (SP ? SP->_use_meta : 0)
472 		      EVENTLIST_2nd((_nc_eventlist *) 0));
473     if (code != ERR)
474 	code = value;
475     returnCode(code);
476 }
477 
478 /*
479 **      int
480 **      kgetch()
481 **
482 **      Get an input character, but take care of keypad sequences, returning
483 **      an appropriate code when one matches the input.  After each character
484 **      is received, set an alarm call based on ESCDELAY.  If no more of the
485 **      sequence is received by the time the alarm goes off, pass through
486 **      the sequence gotten so far.
487 **
488 **	This function must be called when there are no cooked keys in queue.
489 **	(that is head==-1 || peek==head)
490 **
491 */
492 
493 static int
494 kgetch(EVENTLIST_0th(_nc_eventlist * evl))
495 {
496     struct tries *ptr;
497     int ch = 0;
498     int timeleft = ESCDELAY;
499 
500     TR(TRACE_IEVENT, ("kgetch() called"));
501 
502     ptr = SP->_keytry;
503 
504     for (;;) {
505 	if (cooked_key_in_fifo() && SP->_fifo[head] >= KEY_MIN) {
506 	    break;
507 	} else if (!raw_key_in_fifo()) {
508 	    ch = fifo_push(EVENTLIST_1st(evl));
509 	    if (ch == ERR) {
510 		peek = head;	/* the keys stay uninterpreted */
511 		return ERR;
512 	    }
513 #ifdef NCURSES_WGETCH_EVENTS
514 	    else if (ch == KEY_EVENT) {
515 		peek = head;	/* the keys stay uninterpreted */
516 		return fifo_pull();	/* Remove KEY_EVENT from the queue */
517 	    }
518 #endif
519 	}
520 
521 	ch = fifo_peek();
522 	if (ch >= KEY_MIN) {
523 	    /* If not first in queue, somebody put this key there on purpose in
524 	     * emergency.  Consider it higher priority than the unfinished
525 	     * keysequence we are parsing.
526 	     */
527 	    peek = head;
528 	    /* assume the key is the last in fifo */
529 	    t_dec();		/* remove the key */
530 	    return ch;
531 	}
532 
533 	TR(TRACE_IEVENT, ("ch: %s", _tracechar((unsigned char) ch)));
534 	while ((ptr != NULL) && (ptr->ch != (unsigned char) ch))
535 	    ptr = ptr->sibling;
536 
537 	if (ptr == NULL) {
538 	    TR(TRACE_IEVENT, ("ptr is null"));
539 	    break;
540 	}
541 	TR(TRACE_IEVENT, ("ptr=%p, ch=%d, value=%d",
542 			  ptr, ptr->ch, ptr->value));
543 
544 	if (ptr->value != 0) {	/* sequence terminated */
545 	    TR(TRACE_IEVENT, ("end of sequence"));
546 	    if (peek == tail)
547 		fifo_clear();
548 	    else
549 		head = peek;
550 	    return (ptr->value);
551 	}
552 
553 	ptr = ptr->child;
554 
555 	if (!raw_key_in_fifo()) {
556 	    int rc;
557 
558 	    TR(TRACE_IEVENT, ("waiting for rest of sequence"));
559 	    rc = check_mouse_activity(timeleft EVENTLIST_2nd(evl));
560 #ifdef NCURSES_WGETCH_EVENTS
561 	    if (rc & 4) {
562 		TR(TRACE_IEVENT, ("interrupted by a user event"));
563 		/* FIXME Should have preserved remainder timeleft for reuse... */
564 		peek = head;	/* Restart interpreting later */
565 		return KEY_EVENT;
566 	    }
567 #endif
568 	    if (!rc) {
569 		TR(TRACE_IEVENT, ("ran out of time"));
570 		break;
571 	    }
572 	}
573     }
574     ch = fifo_pull();
575     peek = head;
576     return ch;
577 }
578