xref: /openbsd-src/lib/libcurses/base/lib_mouse.c (revision 92dd1ec0a89df25171bc5d61a3d95ea1a68cef0b)
1 /*	$OpenBSD: lib_mouse.c,v 1.1 1999/01/18 19:09:52 millert Exp $	*/
2 
3 /****************************************************************************
4  * Copyright (c) 1998 Free Software Foundation, Inc.                        *
5  *                                                                          *
6  * Permission is hereby granted, free of charge, to any person obtaining a  *
7  * copy of this software and associated documentation files (the            *
8  * "Software"), to deal in the Software without restriction, including      *
9  * without limitation the rights to use, copy, modify, merge, publish,      *
10  * distribute, distribute with modifications, sublicense, and/or sell       *
11  * copies of the Software, and to permit persons to whom the Software is    *
12  * furnished to do so, subject to the following conditions:                 *
13  *                                                                          *
14  * The above copyright notice and this permission notice shall be included  *
15  * in all copies or substantial portions of the Software.                   *
16  *                                                                          *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
18  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
19  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
20  * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
21  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
22  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
23  * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
24  *                                                                          *
25  * Except as contained in this notice, the name(s) of the above copyright   *
26  * holders shall not be used in advertising or otherwise to promote the     *
27  * sale, use or other dealings in this Software without prior written       *
28  * authorization.                                                           *
29  ****************************************************************************/
30 
31 /****************************************************************************
32  *  Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995               *
33  *     and: Eric S. Raymond <esr@snark.thyrsus.com>                         *
34  ****************************************************************************/
35 
36 /*
37  * This module is intended to encapsulate ncurses's interface to pointing
38  * devices.
39  *
40  * The first method used is xterm's internal mouse-tracking facility.
41  * The second (not yet implemented) will be Alessandro Rubini's GPM server.
42  *
43  * Notes for implementors of new mouse-interface methods:
44  *
45  * The code is logically split into a lower level that accepts event reports
46  * in a device-dependent format and an upper level that parses mouse gestures
47  * and filters events.  The mediating data structure is a circular queue of
48  * MEVENT structures.
49  *
50  * Functionally, the lower level's job is to pick up primitive events and
51  * put them on the circular queue.  This can happen in one of two ways:
52  * either (a) _nc_mouse_event() detects a series of incoming mouse reports
53  * and queues them, or (b) code in lib_getch.c detects the kmous prefix in
54  * the keyboard input stream and calls _nc_mouse_inline to queue up a series
55  * of adjacent mouse reports.
56  *
57  * In either case, _nc_mouse_parse() should be called after the series is
58  * accepted to parse the digested mouse reports (low-level MEVENTs) into
59  * a gesture (a high-level or composite MEVENT).
60  *
61  * Don't be too shy about adding new event types or modifiers, if you can find
62  * room for them in the 32-bit mask.  The API is written so that users get
63  * feedback on which theoretical event types they won't see when they call
64  * mousemask. There's one bit per button (the RESERVED_EVENT bit) not being
65  * used yet, and a couple of bits open at the high end.
66  */
67 
68 #ifdef __EMX__
69 #  include "io.h"
70 #  include "fcntl.h"
71 #  define  INCL_DOS
72 #  define  INCL_VIO
73 #  define  INCL_KBD
74 #  define  INCL_MOU
75 #  define  INCL_DOSPROCESS
76 #  include <os2.h>			/* Need to include before the others */
77 #endif
78 
79 #include <curses.priv.h>
80 #include <term.h>
81 
82 #if USE_GPM_SUPPORT
83 #ifndef LINT		/* don't need this for llib-lncurses */
84 #undef buttons		/* term.h defines this, and gpm uses it! */
85 #include <gpm.h>
86 #endif
87 #endif
88 
89 MODULE_ID("$From: lib_mouse.c,v 1.41 1998/12/02 15:03:22 juergen Exp $")
90 
91 #define MY_TRACE TRACE_ICALLS|TRACE_IEVENT
92 
93 #define INVALID_EVENT	-1
94 
95 static int		mousetype;
96 #define M_XTERM		-1	/* use xterm's mouse tracking? */
97 #define M_NONE		0	/* no mouse device */
98 #define M_GPM		1	/* use GPM */
99 #define M_QNX		2	/* QNX mouse on console */
100 #define M_QNX_TERM	3	/* QNX mouse on pterm/xterm (using qansi-m) */
101 
102 #if USE_GPM_SUPPORT
103 #ifndef LINT
104 static Gpm_Connect gpm_connect;
105 #endif
106 #endif
107 
108 static mmask_t	eventmask;		/* current event mask */
109 
110 static bool _nc_mouse_parse(int);
111 static void _nc_mouse_resume(SCREEN *);
112 static void _nc_mouse_wrap(SCREEN *);
113 
114 /* maintain a circular list of mouse events */
115 
116 /* The definition of the circular list size (EV_MAX), is in curses.priv.h, so
117  * wgetch() may refer to the size and call _nc_mouse_parse() before circular
118  * list overflow.
119  */
120 static MEVENT	events[EV_MAX];		/* hold the last mouse event seen */
121 static MEVENT	*eventp = events;	/* next free slot in event queue */
122 #define NEXT(ep)	((ep == events + EV_MAX - 1) ? events : ep + 1)
123 #define PREV(ep)	((ep == events) ? events + EV_MAX - 1 : ep - 1)
124 
125 #ifdef TRACE
126 static void _trace_slot(const char *tag)
127 {
128 	MEVENT *ep;
129 
130 	_tracef(tag);
131 
132 	for (ep = events; ep < events + EV_MAX; ep++)
133 		_tracef("mouse event queue slot %ld = %s",
134 			(long) (ep - events),
135 			_tracemouse(ep));
136 }
137 #endif
138 
139 #ifdef USE_EMX_MOUSE
140 
141 #  define TOP_ROW          0
142 #  define LEFT_COL         0
143 
144 static int mouse_wfd;
145 static int mouse_thread;
146 static int mouse_activated;
147 static char mouse_buttons[] = { 0, 1, 3, 2};
148 
149 
150 #  define M_FD(sp) sp->_mouse_fd
151 
152 static void
153 write_event(int down, int button, int x, int y)
154 {
155     char buf[6];
156     unsigned long ignore;
157 
158     strcpy(buf, key_mouse);
159     buf[3] = ' ' + (button - 1) + (down ? 0 : 0x40);
160     buf[4] = ' ' + x - LEFT_COL + 1;
161     buf[5] = ' ' + y - TOP_ROW + 1;
162     DosWrite(mouse_wfd, buf, 6, &ignore);
163 }
164 
165 static void
166 mouse_server(unsigned long ignored GCC_UNUSED)
167 {
168     unsigned short fWait = MOU_WAIT;
169     /* NOPTRRECT mourt = { 0,0,24,79 }; */
170     MOUEVENTINFO mouev;
171     HMOU hmou;
172     unsigned short mask = MOUSE_BN1_DOWN | MOUSE_BN2_DOWN | MOUSE_BN3_DOWN;
173     int oldstate = 0;
174     char errmess[] = "Unexpected termination of mouse thread\r\n";
175     unsigned long ignore;
176 
177     /* open the handle for the mouse */
178     if (MouOpen(NULL,&hmou) == 0) {
179 
180 	if (MouSetEventMask(&mask,hmou) == 0
181 	 && MouDrawPtr(hmou) == 0) {
182 
183 	    for (;;) {
184 		/* sit and wait on the event queue */
185 		if (MouReadEventQue(&mouev,&fWait,hmou))
186 			break;
187 		if (!mouse_activated)
188 		    goto finish;
189 
190 		/*
191 		 * OS/2 numbers a 3-button mouse inconsistently from other
192 		 * platforms:
193 		 *	1 = left
194 		 *	2 = right
195 		 *	3 = middle.
196 		 */
197 		if ((mouev.fs ^ oldstate) & MOUSE_BN1_DOWN)
198 		    write_event(mouev.fs  & MOUSE_BN1_DOWN,
199 				mouse_buttons[1], mouev.col, mouev.row);
200 		if ((mouev.fs ^ oldstate) & MOUSE_BN2_DOWN)
201 		    write_event(mouev.fs  & MOUSE_BN2_DOWN,
202 				mouse_buttons[3], mouev.col, mouev.row);
203 		if ((mouev.fs ^ oldstate) & MOUSE_BN3_DOWN)
204 		    write_event(mouev.fs  & MOUSE_BN3_DOWN,
205 				mouse_buttons[2], mouev.col, mouev.row);
206 
207 	      finish:
208 		oldstate = mouev.fs;
209 	    }
210 	}
211 
212 	DosWrite(2, errmess, strlen(errmess), &ignore);
213 	MouClose(hmou);
214     }
215     DosExit(EXIT_THREAD, 0L );
216 }
217 static void
218 server_state(const int state)
219 { /* It would be nice to implement pointer-off and stop looping... */
220     mouse_activated = state;
221 }
222 
223 #endif
224 
225 /* FIXME: The list of names should be configurable */
226 static int is_xterm(const char *name)
227 {
228     return (!strncmp(name, "xterm", 5)
229       ||    !strncmp(name, "rxvt",  4)
230       ||    !strncmp(name, "kterm", 5)
231       ||    !strncmp(name, "color_xterm", 11));
232 }
233 
234 static int initialized;
235 
236 static void _nc_mouse_init(void)
237 /* initialize the mouse */
238 {
239     int i;
240 
241     if (initialized) {
242 	return;
243     }
244     initialized = TRUE;
245 
246     TR(MY_TRACE, ("_nc_mouse_init() called"));
247 
248     for (i = 0; i < EV_MAX; i++)
249 	events[i].id = INVALID_EVENT;
250 
251     /* we know how to recognize mouse events under xterm */
252     if (key_mouse != 0
253      && is_xterm(cur_term->type.term_names))
254 	mousetype = M_XTERM;
255 
256 #if USE_GPM_SUPPORT
257     else if (!strncmp(cur_term->type.term_names, "linux", 5))
258     {
259 	/* GPM: initialize connection to gpm server */
260 	gpm_connect.eventMask = GPM_DOWN|GPM_UP;
261 	gpm_connect.defaultMask = ~gpm_connect.eventMask;
262 	gpm_connect.minMod = 0;
263 	gpm_connect.maxMod = ~0;
264 	if (Gpm_Open (&gpm_connect, 0) >= 0) { /* returns the file-descriptor */
265 	    mousetype = M_GPM;
266 	    SP->_mouse_fd = gpm_fd;
267 	}
268     }
269 #endif
270 
271     /* OS/2 VIO */
272 #ifdef USE_EMX_MOUSE
273     if (!mouse_thread && mousetype != M_XTERM && key_mouse) {
274 	int handles[2];
275 	if (pipe(handles) < 0) {
276 	    perror("mouse pipe error");
277 	} else {
278 	    int rc;
279 
280 	    if (!mouse_buttons[0]) {
281 		char *s = getenv("MOUSE_BUTTONS_123");
282 
283 		mouse_buttons[0] = 1;
284 		if (s && strlen(s) >= 3) {
285 		    mouse_buttons[1] = s[0] - '0';
286 		    mouse_buttons[2] = s[1] - '0';
287 		    mouse_buttons[3] = s[2] - '0';
288 		}
289 	    }
290 	    mouse_wfd = handles[1];
291 	    M_FD(SP) = handles[0];
292 	    /* Needed? */
293 	    setmode(handles[0], O_BINARY);
294 	    setmode(handles[1], O_BINARY);
295 	    /* Do not use CRT functions, we may single-threaded. */
296 	    rc = DosCreateThread((unsigned long*)&mouse_thread, mouse_server, 0, 0, 8192);
297 	    if (rc)
298 		printf("mouse thread error %d=%#x", rc, rc);
299 	    else
300 		mousetype = M_XTERM;
301 	}
302     }
303 #endif
304 
305     T(("_nc_mouse_init() set mousetype to %d", mousetype));
306 }
307 
308 static bool _nc_mouse_event(SCREEN *sp GCC_UNUSED)
309 /* query to see if there is a pending mouse event */
310 {
311 #if USE_GPM_SUPPORT
312     /* GPM: query server for event, return TRUE if we find one */
313     Gpm_Event ev;
314 
315     if (gpm_fd >= 0
316      && _nc_timed_wait(2, 0, (int *)0)
317      && Gpm_GetEvent(&ev) == 1)
318     {
319 	eventp->id = 0;		/* there's only one mouse... */
320 
321 	eventp->bstate = 0;
322 	switch (ev.type & 0x0f)
323 	{
324 	case(GPM_DOWN):
325 	    if (ev.buttons & GPM_B_LEFT)   eventp->bstate |= BUTTON1_PRESSED;
326 	    if (ev.buttons & GPM_B_MIDDLE) eventp->bstate |= BUTTON2_PRESSED;
327 	    if (ev.buttons & GPM_B_RIGHT)  eventp->bstate |= BUTTON3_PRESSED;
328 	    break;
329 	case(GPM_UP):
330 	    if (ev.buttons & GPM_B_LEFT)   eventp->bstate |= BUTTON1_RELEASED;
331 	    if (ev.buttons & GPM_B_MIDDLE) eventp->bstate |= BUTTON2_RELEASED;
332 	    if (ev.buttons & GPM_B_RIGHT)  eventp->bstate |= BUTTON3_RELEASED;
333 	    break;
334 	default:
335 	    break;
336 	}
337 
338 	eventp->x = ev.x - 1;
339 	eventp->y = ev.y - 1;
340 	eventp->z = 0;
341 
342 	/* bump the next-free pointer into the circular list */
343 	eventp = NEXT(eventp);
344 	return (TRUE);
345     }
346 #endif
347 
348     /* xterm: never have to query, mouse events are in the keyboard stream */
349     return(FALSE);	/* no event waiting */
350 }
351 
352 static bool _nc_mouse_inline(SCREEN *sp)
353 /* mouse report received in the keyboard stream -- parse its info */
354 {
355     TR(MY_TRACE, ("_nc_mouse_inline() called"));
356 
357     if (mousetype == M_XTERM)
358     {
359 	unsigned char	kbuf[4];
360 	MEVENT	*prev;
361 	size_t	grabbed;
362 	int	res;
363 
364 	/* This code requires that your xterm entry contain the kmous
365 	 * capability and that it be set to the \E[M documented in the
366 	 * Xterm Control Sequences reference.  This is how we
367 	 * arrange for mouse events to be reported via a KEY_MOUSE
368 	 * return value from wgetch().  After this value is received,
369 	 * _nc_mouse_inline() gets called and is immediately
370 	 * responsible for parsing the mouse status information
371 	 * following the prefix.
372 	 *
373 	 * The following quotes from the ctrlseqs.ms document in the
374 	 * X distribution, describing the X mouse tracking feature:
375 	 *
376 	 * Parameters for all mouse tracking escape sequences
377 	 * generated by xterm encode numeric parameters in a single
378 	 * character as value+040.  For example, !  is 1.
379 	 *
380 	 * On button press or release, xterm sends ESC [ M CbCxCy.
381 	 * The low two bits of Cb encode button information: 0=MB1
382 	 * pressed, 1=MB2 pressed, 2=MB3 pressed, 3=release.  The
383 	 * upper bits encode what modifiers were down when the
384 	 * button was pressed and are added together.  4=Shift,
385 	 * 8=Meta, 16=Control.  Cx and Cy are the x and y coordinates
386 	 * of the mouse event.  The upper left corner is (1,1).
387 	 *
388 	 * (End quote)  By the time we get here, we've eaten the
389 	 * key prefix.  FYI, the loop below is necessary because
390 	 * mouse click info isn't guaranteed to present as a
391 	 * single clist item.  It always does under Linux but often
392 	 * fails to under Solaris.
393 	 */
394 	for (grabbed = 0; grabbed < 3; grabbed += res)
395 	{
396 
397 	/* For VIO mouse we add extra bit 64 to disambiguate button-up. */
398 #ifdef USE_EMX_MOUSE
399 	     res = read( M_FD(sp) >= 0 ? M_FD(sp) : sp->_ifd, &kbuf, 3);
400 #else
401 	     res = read(sp->_ifd, kbuf + grabbed, 3-grabbed);
402 #endif
403 	     if (res == -1)
404 		 break;
405 	}
406 	kbuf[3] = '\0';
407 
408 	TR(TRACE_IEVENT, ("_nc_mouse_inline sees the following xterm data: '%s'", kbuf));
409 
410 	eventp->id = 0;		/* there's only one mouse... */
411 
412 	/* processing code goes here */
413 	eventp->bstate = 0;
414 	switch (kbuf[0] & 0x3)
415 	{
416 	case 0x0:
417 	    eventp->bstate = BUTTON1_PRESSED;
418 #ifdef USE_EMX_MOUSE
419 	    if (kbuf[0] & 0x40)
420 		eventp->bstate = BUTTON1_RELEASED;
421 #endif
422 	    break;
423 
424 	case 0x1:
425 	    eventp->bstate = BUTTON2_PRESSED;
426 #ifdef USE_EMX_MOUSE
427 	    if (kbuf[0] & 0x40)
428 		eventp->bstate = BUTTON2_RELEASED;
429 #endif
430 	    break;
431 
432 	case 0x2:
433 	    eventp->bstate = BUTTON3_PRESSED;
434 #ifdef USE_EMX_MOUSE
435 	    if (kbuf[0] & 0x40)
436 		eventp->bstate = BUTTON3_RELEASED;
437 #endif
438 	    break;
439 
440 	case 0x3:
441 	    /*
442 	     * Release events aren't reported for individual buttons,
443 	     * just for the button set as a whole...
444 	     */
445 	    eventp->bstate =
446 		(BUTTON1_RELEASED |
447 		 BUTTON2_RELEASED |
448 		 BUTTON3_RELEASED);
449 	    /*
450 	     * ...however, because there are no kinds of mouse events under
451 	     * xterm that can intervene between press and release, we can
452 	     * deduce which buttons were actually released by looking at the
453 	     * previous event.
454 	     */
455 	    prev = PREV(eventp);
456 	    if (!(prev->bstate & BUTTON1_PRESSED))
457 		eventp->bstate &=~ BUTTON1_RELEASED;
458 	    if (!(prev->bstate & BUTTON2_PRESSED))
459 		eventp->bstate &=~ BUTTON2_RELEASED;
460 	    if (!(prev->bstate & BUTTON3_PRESSED))
461 		eventp->bstate &=~ BUTTON3_RELEASED;
462 	    break;
463 	}
464 
465 	if (kbuf[0] & 4) {
466 	    eventp->bstate |= BUTTON_SHIFT;
467 	}
468 	if (kbuf[0] & 8) {
469 	    eventp->bstate |= BUTTON_ALT;
470 	}
471 	if (kbuf[0] & 16) {
472 	    eventp->bstate |= BUTTON_CTRL;
473 	}
474 
475 	eventp->x = (kbuf[1] - ' ') - 1;
476 	eventp->y = (kbuf[2] - ' ') - 1;
477 	TR(MY_TRACE, ("_nc_mouse_inline: primitive mouse-event %s has slot %ld",
478 		_tracemouse(eventp),
479 		(long) (eventp - events)));
480 
481 	/* bump the next-free pointer into the circular list */
482 	eventp = NEXT(eventp);
483 #if 0	/* this return would be needed for QNX's mods to lib_getch.c */
484 	return(TRUE);
485 #endif
486     }
487 
488     return(FALSE);
489 }
490 
491 static void mouse_activate(bool on)
492 {
493     if (!on && !initialized)
494 	return;
495 
496     _nc_mouse_init();
497 
498     if (on) {
499 
500 	switch (mousetype) {
501 	case M_XTERM:
502 #ifdef NCURSES_EXT_FUNCS
503 	    keyok(KEY_MOUSE, on);
504 #endif
505 	    TPUTS_TRACE("xterm mouse initialization");
506 #ifdef USE_EMX_MOUSE
507 	    server_state(1);
508 #else
509 	    putp("\033[?1000h");
510 #endif
511 	    break;
512 #if USE_GPM_SUPPORT
513 	case M_GPM:
514 	    SP->_mouse_fd = gpm_fd;
515 	    break;
516 #endif
517 	}
518 	/* Make runtime binding to cut down on object size of applications that
519 	 * do not use the mouse (e.g., 'clear').
520 	 */
521 	SP->_mouse_event  = _nc_mouse_event;
522 	SP->_mouse_inline = _nc_mouse_inline;
523 	SP->_mouse_parse  = _nc_mouse_parse;
524 	SP->_mouse_resume = _nc_mouse_resume;
525 	SP->_mouse_wrap   = _nc_mouse_wrap;
526 
527     } else {
528 
529 	switch (mousetype) {
530 	case M_XTERM:
531 	    TPUTS_TRACE("xterm mouse deinitialization");
532 #ifdef USE_EMX_MOUSE
533 	    server_state(0);
534 #else
535 	    putp("\033[?1000l");
536 #endif
537 	    break;
538 #if USE_GPM_SUPPORT
539 	case M_GPM:
540 	    break;
541 #endif
542 	}
543     }
544     (void) fflush(SP->_ofp);
545 }
546 
547 /**************************************************************************
548  *
549  * Device-independent code
550  *
551  **************************************************************************/
552 
553 static bool _nc_mouse_parse(int runcount)
554 /* parse a run of atomic mouse events into a gesture */
555 {
556     MEVENT	*ep, *runp, *next, *prev = PREV(eventp);
557     int		n;
558     bool	merge;
559 
560     TR(MY_TRACE, ("_nc_mouse_parse(%d) called", runcount));
561 
562     /*
563      * When we enter this routine, the event list next-free pointer
564      * points just past a run of mouse events that we know were separated
565      * in time by less than the critical click interval. The job of this
566      * routine is to collaps this run into a single higher-level event
567      * or gesture.
568      *
569      * We accomplish this in two passes.  The first pass merges press/release
570      * pairs into click events.  The second merges runs of click events into
571      * double or triple-click events.
572      *
573      * It's possible that the run may not resolve to a single event (for
574      * example, if the user quadruple-clicks).  If so, leading events
575      * in the run are ignored.
576      *
577      * Note that this routine is independent of the format of the specific
578      * format of the pointing-device's reports.  We can use it to parse
579      * gestures on anything that reports press/release events on a per-
580      * button basis, as long as the device-dependent mouse code puts stuff
581      * on the queue in MEVENT format.
582      */
583     if (runcount == 1)
584     {
585 	TR(MY_TRACE, ("_nc_mouse_parse: returning simple mouse event %s at slot %ld",
586 	   _tracemouse(prev),
587 	   (long) (prev - events)));
588 	return (prev->id >= 0)
589 		? ((prev->bstate & eventmask) ? TRUE : FALSE)
590 		: FALSE;
591     }
592 
593     /* find the start of the run */
594     runp = eventp;
595     for (n = runcount; n > 0; n--) {
596 	runp = PREV(runp);
597     }
598 
599 #ifdef TRACE
600     if (_nc_tracing & TRACE_IEVENT)
601     {
602 	_trace_slot("before mouse press/release merge:");
603 	_tracef("_nc_mouse_parse: run starts at %ld, ends at %ld, count %d",
604 	    (long) (runp - events),
605 	    (long) ((eventp - events) + (EV_MAX-1)) % EV_MAX,
606 	    runcount);
607     }
608 #endif /* TRACE */
609 
610     /* first pass; merge press/release pairs */
611     do {
612 	merge = FALSE;
613 	for (ep = runp; next = NEXT(ep), next != eventp; ep = next)
614 	{
615 	    if (ep->x == next->x && ep->y == next->y
616 		&& (ep->bstate & (BUTTON1_PRESSED|BUTTON2_PRESSED|BUTTON3_PRESSED))
617 		&& (!(ep->bstate & BUTTON1_PRESSED)
618 		    == !(next->bstate & BUTTON1_RELEASED))
619 		&& (!(ep->bstate & BUTTON2_PRESSED)
620 		    == !(next->bstate & BUTTON2_RELEASED))
621 		&& (!(ep->bstate & BUTTON3_PRESSED)
622 		    == !(next->bstate & BUTTON3_RELEASED))
623 		)
624 	    {
625 		if ((eventmask & BUTTON1_CLICKED)
626 			&& (ep->bstate & BUTTON1_PRESSED))
627 		{
628 		    ep->bstate &=~ BUTTON1_PRESSED;
629 		    ep->bstate |= BUTTON1_CLICKED;
630 		    merge = TRUE;
631 		}
632 		if ((eventmask & BUTTON2_CLICKED)
633 			&& (ep->bstate & BUTTON2_PRESSED))
634 		{
635 		    ep->bstate &=~ BUTTON2_PRESSED;
636 		    ep->bstate |= BUTTON2_CLICKED;
637 		    merge = TRUE;
638 		}
639 		if ((eventmask & BUTTON3_CLICKED)
640 			&& (ep->bstate & BUTTON3_PRESSED))
641 		{
642 		    ep->bstate &=~ BUTTON3_PRESSED;
643 		    ep->bstate |= BUTTON3_CLICKED;
644 		    merge = TRUE;
645 		}
646 		if (merge)
647 		    next->id = INVALID_EVENT;
648 	    }
649 	}
650     } while
651 	(merge);
652 
653 #ifdef TRACE
654     if (_nc_tracing & TRACE_IEVENT)
655     {
656 	_trace_slot("before mouse click merge:");
657 	_tracef("_nc_mouse_parse: run starts at %ld, ends at %ld, count %d",
658 	    (long) (runp - events),
659 	    (long) ((eventp - events) + (EV_MAX-1)) % EV_MAX,
660 	    runcount);
661     }
662 #endif /* TRACE */
663 
664     /*
665      * Second pass; merge click runs.  At this point, click events are
666      * each followed by one invalid event. We merge click events
667      * forward in the queue.
668      *
669      * NOTE: There is a problem with this design!  If the application
670      * allows enough click events to pile up in the circular queue so
671      * they wrap around, it will cheerfully merge the newest forward
672      * into the oldest, creating a bogus doubleclick and confusing
673      * the queue-traversal logic rather badly.  Generally this won't
674      * happen, because calling getmouse() marks old events invalid and
675      * ineligible for merges.  The true solution to this problem would
676      * be to timestamp each MEVENT and perform the obvious sanity check,
677      * but the timer element would have to have sub-second resolution,
678      * which would get us into portability trouble.
679      */
680     do {
681 	MEVENT	*follower;
682 
683 	merge = FALSE;
684 	for (ep = runp; next = NEXT(ep), next != eventp; ep = next)
685 	    if (ep->id != INVALID_EVENT)
686 	    {
687 		if (next->id != INVALID_EVENT)
688 		    continue;
689 		follower = NEXT(next);
690 		if (follower->id == INVALID_EVENT)
691 		    continue;
692 
693 		/* merge click events forward */
694 		if ((ep->bstate &
695 			(BUTTON1_CLICKED | BUTTON2_CLICKED | BUTTON3_CLICKED))
696 		    && (follower->bstate &
697 			(BUTTON1_CLICKED | BUTTON2_CLICKED | BUTTON3_CLICKED)))
698 		{
699 		    if ((eventmask & BUTTON1_DOUBLE_CLICKED)
700 			&& (follower->bstate & BUTTON1_CLICKED))
701 		    {
702 			follower->bstate &=~ BUTTON1_CLICKED;
703 			follower->bstate |= BUTTON1_DOUBLE_CLICKED;
704 			merge = TRUE;
705 		    }
706 		    if ((eventmask & BUTTON2_DOUBLE_CLICKED)
707 			&& (follower->bstate & BUTTON2_CLICKED))
708 		    {
709 			follower->bstate &=~ BUTTON2_CLICKED;
710 			follower->bstate |= BUTTON2_DOUBLE_CLICKED;
711 			merge = TRUE;
712 		    }
713 		    if ((eventmask & BUTTON3_DOUBLE_CLICKED)
714 			&& (follower->bstate & BUTTON3_CLICKED))
715 		    {
716 			follower->bstate &=~ BUTTON3_CLICKED;
717 			follower->bstate |= BUTTON3_DOUBLE_CLICKED;
718 			merge = TRUE;
719 		    }
720 		    if (merge)
721 			ep->id = INVALID_EVENT;
722 		}
723 
724 		/* merge double-click events forward */
725 		if ((ep->bstate &
726 			(BUTTON1_DOUBLE_CLICKED
727 			 | BUTTON2_DOUBLE_CLICKED
728 			 | BUTTON3_DOUBLE_CLICKED))
729 		    && (follower->bstate &
730 			(BUTTON1_CLICKED | BUTTON2_CLICKED | BUTTON3_CLICKED)))
731 		{
732 		    if ((eventmask & BUTTON1_TRIPLE_CLICKED)
733 			&& (follower->bstate & BUTTON1_CLICKED))
734 		    {
735 			follower->bstate &=~ BUTTON1_CLICKED;
736 			follower->bstate |= BUTTON1_TRIPLE_CLICKED;
737 			merge = TRUE;
738 		    }
739 		    if ((eventmask & BUTTON2_TRIPLE_CLICKED)
740 			&& (follower->bstate & BUTTON2_CLICKED))
741 		    {
742 			follower->bstate &=~ BUTTON2_CLICKED;
743 			follower->bstate |= BUTTON2_TRIPLE_CLICKED;
744 			merge = TRUE;
745 		    }
746 		    if ((eventmask & BUTTON3_TRIPLE_CLICKED)
747 			&& (follower->bstate & BUTTON3_CLICKED))
748 		    {
749 			follower->bstate &=~ BUTTON3_CLICKED;
750 			follower->bstate |= BUTTON3_TRIPLE_CLICKED;
751 			merge = TRUE;
752 		    }
753 		    if (merge)
754 			ep->id = INVALID_EVENT;
755 		}
756 	    }
757     } while
758 	(merge);
759 
760 #ifdef TRACE
761     if (_nc_tracing & TRACE_IEVENT)
762     {
763 	_trace_slot("before mouse event queue compaction:");
764 	_tracef("_nc_mouse_parse: run starts at %ld, ends at %ld, count %d",
765 	    (long) (runp - events),
766 	    (long) ((eventp - events) + (EV_MAX-1)) % EV_MAX,
767 	    runcount);
768     }
769 #endif /* TRACE */
770 
771     /*
772      * Now try to throw away trailing events flagged invalid, or that
773      * don't match the current event mask.
774      */
775     for (; runcount; prev = PREV(eventp), runcount--)
776 	if (prev->id == INVALID_EVENT || !(prev->bstate & eventmask)) {
777 	    eventp = prev;
778 	}
779 
780 #ifdef TRACE
781     if (_nc_tracing & TRACE_IEVENT)
782     {
783 	_trace_slot("after mouse event queue compaction:");
784 	_tracef("_nc_mouse_parse: run starts at %ld, ends at %ld, count %d",
785 	    (long) (runp - events),
786 	    (long) ((eventp - events) + (EV_MAX-1)) % EV_MAX,
787 	    runcount);
788     }
789     for (ep = runp; ep != eventp; ep = NEXT(ep))
790 	if (ep->id != INVALID_EVENT)
791 	    TR(MY_TRACE, ("_nc_mouse_parse: returning composite mouse event %s at slot %ld",
792 		_tracemouse(ep),
793 		(long) (ep - events)));
794 #endif /* TRACE */
795 
796     /* after all this, do we have a valid event? */
797     return(PREV(eventp)->id != INVALID_EVENT);
798 }
799 
800 static void _nc_mouse_wrap(SCREEN *sp GCC_UNUSED)
801 /* release mouse -- called by endwin() before shellout/exit */
802 {
803     TR(MY_TRACE, ("_nc_mouse_wrap() called"));
804 
805     switch (mousetype) {
806     case M_XTERM:
807         if (eventmask)
808             mouse_activate(FALSE);
809         break;
810 #if USE_GPM_SUPPORT
811 	/* GPM: pass all mouse events to next client */
812 	case M_GPM:
813 	    break;
814 #endif
815     }
816 }
817 
818 static void _nc_mouse_resume(SCREEN *sp GCC_UNUSED)
819 /* re-connect to mouse -- called by doupdate() after shellout */
820 {
821     TR(MY_TRACE, ("_nc_mouse_resume() called"));
822 
823     /* xterm: re-enable reporting */
824     if (mousetype == M_XTERM && eventmask)
825 	mouse_activate(TRUE);
826 
827     /* GPM: reclaim our event set */
828 }
829 
830 /**************************************************************************
831  *
832  * Mouse interface entry points for the API
833  *
834  **************************************************************************/
835 
836 int getmouse(MEVENT *aevent)
837 /* grab a copy of the current mouse event */
838 {
839     T((T_CALLED("getmouse(%p)"), aevent));
840 
841     if (aevent && (mousetype != M_NONE))
842     {
843 	/* compute the current-event pointer */
844 	MEVENT	*prev = PREV(eventp);
845 
846 	/* copy the event we find there */
847 	*aevent = *prev;
848 
849 	TR(TRACE_IEVENT, ("getmouse: returning event %s from slot %ld",
850 	    _tracemouse(prev),
851 	    (long) (prev - events)));
852 
853 	prev->id = INVALID_EVENT;	/* so the queue slot becomes free */
854 	returnCode(OK);
855     }
856     returnCode(ERR);
857 }
858 
859 int ungetmouse(MEVENT *aevent)
860 /* enqueue a synthesized mouse event to be seen by the next wgetch() */
861 {
862     /* stick the given event in the next-free slot */
863     *eventp = *aevent;
864 
865     /* bump the next-free pointer into the circular list */
866     eventp = NEXT(eventp);
867 
868     /* push back the notification event on the keyboard queue */
869     return ungetch(KEY_MOUSE);
870 }
871 
872 mmask_t mousemask(mmask_t newmask, mmask_t *oldmask)
873 /* set the mouse event mask */
874 {
875     mmask_t result = 0;
876 
877     T((T_CALLED("mousemask(%#lx,%p)"), newmask, oldmask));
878 
879     if (oldmask)
880 	*oldmask = eventmask;
881 
882     if (!newmask && !initialized)
883 	returnCode(0);
884 
885     _nc_mouse_init();
886     if ( mousetype != M_NONE )
887     {
888 	eventmask = newmask &
889 	    (BUTTON_ALT | BUTTON_CTRL | BUTTON_SHIFT
890 	     | BUTTON1_PRESSED | BUTTON1_RELEASED | BUTTON1_CLICKED
891 	     | BUTTON1_DOUBLE_CLICKED | BUTTON1_TRIPLE_CLICKED
892 	     | BUTTON2_PRESSED | BUTTON2_RELEASED | BUTTON2_CLICKED
893 	     | BUTTON2_DOUBLE_CLICKED | BUTTON2_TRIPLE_CLICKED
894 	     | BUTTON3_PRESSED | BUTTON3_RELEASED | BUTTON3_CLICKED
895 	     | BUTTON3_DOUBLE_CLICKED | BUTTON3_TRIPLE_CLICKED);
896 
897 	mouse_activate(eventmask != 0);
898 
899 	result = eventmask;
900     }
901 
902     returnCode(result);
903 }
904 
905 bool wenclose(const WINDOW *win, int y, int x)
906 /* check to see if given window encloses given screen location */
907 {
908     if (win)
909     {
910 	y -= win->_yoffset;
911 	return ((win->_begy <= y &&
912 		 win->_begx <= x &&
913 		 (win->_begx + win->_maxx) >= x &&
914 		 (win->_begy + win->_maxy) >= y) ? TRUE : FALSE);
915     }
916     return FALSE;
917 }
918 
919 int mouseinterval(int maxclick)
920 /* set the maximum mouse interval within which to recognize a click */
921 {
922     int oldval;
923 
924     if (SP != 0) {
925 	oldval = SP->_maxclick;
926 	if (maxclick >= 0)
927 	    SP->_maxclick = maxclick;
928     } else {
929 	oldval = DEFAULT_MAXCLICK;
930     }
931 
932     return(oldval);
933 }
934 
935 /* This may be used by other routines to ask for the existence of mouse
936    support */
937 int _nc_has_mouse(void) {
938   return (mousetype==M_NONE ? 0:1);
939 }
940 
941 bool wmouse_trafo(const WINDOW* win, int* pY, int* pX, bool to_screen)
942 {
943   bool result = FALSE;
944 
945   if (win && pY && pX)
946     {
947       int y = *pY; int x = *pX;
948 
949       if (to_screen)
950 	{
951 	  y += win->_begy + win->_yoffset;
952 	  x += win->_begx;
953 	  if (wenclose(win,y,x))
954 	    result = TRUE;
955 	}
956       else
957 	{
958 	  if (wenclose(win,y,x))
959 	    {
960 	      y -= (win->_begy + win->_yoffset);
961 	      x -= win->_begx;
962 	      result = TRUE;
963 	    }
964 	}
965       if (result)
966 	{
967 	  *pX = x;
968 	  *pY = y;
969 	}
970     }
971   return(result);
972 }
973 
974 /* lib_mouse.c ends here */
975