xref: /openbsd/lib/libcurses/base/lib_mouse.c (revision 898184e3)
1 /* $OpenBSD: lib_mouse.c,v 1.14 2010/01/12 23:22:06 nicm Exp $ */
2 
3 /****************************************************************************
4  * Copyright (c) 1998-2007,2008 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      *
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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  *     and: Thomas E. Dickey                        1996-on                 *
35  ****************************************************************************/
36 
37 /*
38  * This module is intended to encapsulate ncurses's interface to pointing
39  * devices.
40  *
41  * The primary method used is xterm's internal mouse-tracking facility.
42  * Additional methods depend on the platform:
43  *	Alessandro Rubini's GPM server (Linux)
44  *	sysmouse (FreeBSD)
45  *	special-purpose mouse interface for OS/2 EMX.
46  *
47  * Notes for implementors of new mouse-interface methods:
48  *
49  * The code is logically split into a lower level that accepts event reports
50  * in a device-dependent format and an upper level that parses mouse gestures
51  * and filters events.  The mediating data structure is a circular queue of
52  * MEVENT structures.
53  *
54  * Functionally, the lower level's job is to pick up primitive events and
55  * put them on the circular queue.  This can happen in one of two ways:
56  * either (a) _nc_mouse_event() detects a series of incoming mouse reports
57  * and queues them, or (b) code in lib_getch.c detects the kmous prefix in
58  * the keyboard input stream and calls _nc_mouse_inline to queue up a series
59  * of adjacent mouse reports.
60  *
61  * In either case, _nc_mouse_parse() should be called after the series is
62  * accepted to parse the digested mouse reports (low-level MEVENTs) into
63  * a gesture (a high-level or composite MEVENT).
64  *
65  * Don't be too shy about adding new event types or modifiers, if you can find
66  * room for them in the 32-bit mask.  The API is written so that users get
67  * feedback on which theoretical event types they won't see when they call
68  * mousemask. There's one bit per button (the RESERVED_EVENT bit) not being
69  * used yet, and a couple of bits open at the high end.
70  */
71 
72 #ifdef __EMX__
73 #  include <io.h>
74 #  define  INCL_DOS
75 #  define  INCL_VIO
76 #  define  INCL_KBD
77 #  define  INCL_MOU
78 #  define  INCL_DOSPROCESS
79 #  include <os2.h>		/* Need to include before the others */
80 #endif
81 
82 #include <curses.priv.h>
83 
84 MODULE_ID("$Id: lib_mouse.c,v 1.14 2010/01/12 23:22:06 nicm Exp $")
85 
86 #include <term.h>
87 #include <tic.h>
88 
89 #if USE_GPM_SUPPORT
90 #include <linux/keyboard.h>	/* defines KG_* macros */
91 
92 #ifdef HAVE_LIBDL
93 /* use dynamic loader to avoid linkage dependency */
94 #include <dlfcn.h>
95 
96 #ifdef RTLD_NOW
97 #define my_RTLD RTLD_NOW
98 #else
99 #ifdef RTLD_LAZY
100 #define my_RTLD RTLD_LAZY
101 #else
102 make an error
103 #endif
104 #endif				/* RTLD_NOW */
105 #endif				/* HAVE_LIBDL */
106 
107 #endif				/* USE_GPM_SUPPORT */
108 
109 #if USE_SYSMOUSE
110 #undef buttons			/* symbol conflict in consio.h */
111 #undef mouse_info		/* symbol conflict in consio.h */
112 #include <osreldate.h>
113 #if (__FreeBSD_version >= 400017)
114 #include <sys/consio.h>
115 #include <sys/fbio.h>
116 #else
117 #include <machine/console.h>
118 #endif
119 #endif				/* use_SYSMOUSE */
120 
121 #define MY_TRACE TRACE_ICALLS|TRACE_IEVENT
122 
123 #define	MASK_RELEASE(x)		NCURSES_MOUSE_MASK(x, 001)
124 #define	MASK_PRESS(x)		NCURSES_MOUSE_MASK(x, 002)
125 #define	MASK_CLICK(x)		NCURSES_MOUSE_MASK(x, 004)
126 #define	MASK_DOUBLE_CLICK(x)	NCURSES_MOUSE_MASK(x, 010)
127 #define	MASK_TRIPLE_CLICK(x)	NCURSES_MOUSE_MASK(x, 020)
128 #define	MASK_RESERVED_EVENT(x)	NCURSES_MOUSE_MASK(x, 040)
129 
130 #if NCURSES_MOUSE_VERSION == 1
131 #define BUTTON_CLICKED        (BUTTON1_CLICKED        | BUTTON2_CLICKED        | BUTTON3_CLICKED        | BUTTON4_CLICKED)
132 #define BUTTON_PRESSED        (BUTTON1_PRESSED        | BUTTON2_PRESSED        | BUTTON3_PRESSED        | BUTTON4_PRESSED)
133 #define BUTTON_RELEASED       (BUTTON1_RELEASED       | BUTTON2_RELEASED       | BUTTON3_RELEASED       | BUTTON4_RELEASED)
134 #define BUTTON_DOUBLE_CLICKED (BUTTON1_DOUBLE_CLICKED | BUTTON2_DOUBLE_CLICKED | BUTTON3_DOUBLE_CLICKED | BUTTON4_DOUBLE_CLICKED)
135 #define BUTTON_TRIPLE_CLICKED (BUTTON1_TRIPLE_CLICKED | BUTTON2_TRIPLE_CLICKED | BUTTON3_TRIPLE_CLICKED | BUTTON4_TRIPLE_CLICKED)
136 #define MAX_BUTTONS  4
137 #else
138 #define BUTTON_CLICKED        (BUTTON1_CLICKED        | BUTTON2_CLICKED        | BUTTON3_CLICKED        | BUTTON4_CLICKED        | BUTTON5_CLICKED)
139 #define BUTTON_PRESSED        (BUTTON1_PRESSED        | BUTTON2_PRESSED        | BUTTON3_PRESSED        | BUTTON4_PRESSED        | BUTTON5_PRESSED)
140 #define BUTTON_RELEASED       (BUTTON1_RELEASED       | BUTTON2_RELEASED       | BUTTON3_RELEASED       | BUTTON4_RELEASED       | BUTTON5_RELEASED)
141 #define BUTTON_DOUBLE_CLICKED (BUTTON1_DOUBLE_CLICKED | BUTTON2_DOUBLE_CLICKED | BUTTON3_DOUBLE_CLICKED | BUTTON4_DOUBLE_CLICKED | BUTTON5_DOUBLE_CLICKED)
142 #define BUTTON_TRIPLE_CLICKED (BUTTON1_TRIPLE_CLICKED | BUTTON2_TRIPLE_CLICKED | BUTTON3_TRIPLE_CLICKED | BUTTON4_TRIPLE_CLICKED | BUTTON5_TRIPLE_CLICKED)
143 #define MAX_BUTTONS  5
144 #endif
145 
146 #define INVALID_EVENT	-1
147 #define NORMAL_EVENT	0
148 
149 #if USE_GPM_SUPPORT
150 
151 #ifndef LIBGPM_SONAME
152 #define LIBGPM_SONAME "libgpm.so"
153 #endif
154 
155 #define GET_DLSYM(name) (my_##name = (TYPE_##name) dlsym(SP->_dlopen_gpm, #name))
156 
157 #endif				/* USE_GPM_SUPPORT */
158 
159 static bool _nc_mouse_parse(SCREEN *, int);
160 static void _nc_mouse_resume(SCREEN *);
161 static void _nc_mouse_wrap(SCREEN *);
162 
163 /* maintain a circular list of mouse events */
164 
165 #define FirstEV(sp)	((sp)->_mouse_events)
166 #define LastEV(sp)	((sp)->_mouse_events + EV_MAX - 1)
167 
168 #undef  NEXT
169 #define NEXT(ep)	((ep >= LastEV(sp)) \
170 			 ? FirstEV(sp) \
171 			 : ep + 1)
172 
173 #undef  PREV
174 #define PREV(ep)	((ep <= FirstEV(sp)) \
175 			 ? LastEV(sp) \
176 			 : ep - 1)
177 
178 #define IndexEV(sp, ep)	(ep - FirstEV(sp))
179 
180 #define RunParams(sp, eventp, runp) \
181 		(long) IndexEV(sp, runp), \
182 		(long) (IndexEV(sp, eventp) + (EV_MAX - 1)) % EV_MAX
183 
184 #ifdef TRACE
185 static void
186 _trace_slot(SCREEN *sp, const char *tag)
187 {
188     MEVENT *ep;
189 
190     _tracef(tag);
191 
192     for (ep = FirstEV(sp); ep <= LastEV(sp); ep++)
193 	_tracef("mouse event queue slot %ld = %s",
194 		(long) IndexEV(sp, ep),
195 		_nc_tracemouse(sp, ep));
196 }
197 #endif
198 
199 #if USE_EMX_MOUSE
200 
201 #  define TOP_ROW          0
202 #  define LEFT_COL         0
203 
204 #  define M_FD(sp) sp->_mouse_fd
205 
206 static void
207 write_event(SCREEN *sp, int down, int button, int x, int y)
208 {
209     char buf[6];
210     unsigned long ignore;
211 
212     strncpy(buf, key_mouse, 3);	/* should be "\033[M" */
213     buf[3] = ' ' + (button - 1) + (down ? 0 : 0x40);
214     buf[4] = ' ' + x - LEFT_COL + 1;
215     buf[5] = ' ' + y - TOP_ROW + 1;
216     DosWrite(sp->_emxmouse_wfd, buf, 6, &ignore);
217 }
218 
219 static void
220 mouse_server(unsigned long param)
221 {
222     SCREEN *sp = (SCREEN *) param;
223     unsigned short fWait = MOU_WAIT;
224     /* NOPTRRECT mourt = { 0,0,24,79 }; */
225     MOUEVENTINFO mouev;
226     HMOU hmou;
227     unsigned short mask = MOUSE_BN1_DOWN | MOUSE_BN2_DOWN | MOUSE_BN3_DOWN;
228     int nbuttons = 3;
229     int oldstate = 0;
230     char err[80];
231     unsigned long rc;
232 
233     /* open the handle for the mouse */
234     if (MouOpen(NULL, &hmou) == 0) {
235 	rc = MouSetEventMask(&mask, hmou);
236 	if (rc) {		/* retry with 2 buttons */
237 	    mask = MOUSE_BN1_DOWN | MOUSE_BN2_DOWN;
238 	    rc = MouSetEventMask(&mask, hmou);
239 	    nbuttons = 2;
240 	}
241 	if (rc == 0 && MouDrawPtr(hmou) == 0) {
242 	    for (;;) {
243 		/* sit and wait on the event queue */
244 		rc = MouReadEventQue(&mouev, &fWait, hmou);
245 		if (rc) {
246 		    snprintf(err, sizeof(err), "Error reading mouse queue, rc=%lu.\r\n", rc);
247 		    break;
248 		}
249 		if (!sp->_emxmouse_activated)
250 		    goto finish;
251 
252 		/*
253 		 * OS/2 numbers a 3-button mouse inconsistently from other
254 		 * platforms:
255 		 *      1 = left
256 		 *      2 = right
257 		 *      3 = middle.
258 		 */
259 		if ((mouev.fs ^ oldstate) & MOUSE_BN1_DOWN)
260 		    write_event(sp, mouev.fs & MOUSE_BN1_DOWN,
261 				sp->_emxmouse_buttons[1], mouev.col, mouev.row);
262 		if ((mouev.fs ^ oldstate) & MOUSE_BN2_DOWN)
263 		    write_event(sp, mouev.fs & MOUSE_BN2_DOWN,
264 				sp->_emxmouse_buttons[3], mouev.col, mouev.row);
265 		if ((mouev.fs ^ oldstate) & MOUSE_BN3_DOWN)
266 		    write_event(sp, mouev.fs & MOUSE_BN3_DOWN,
267 				sp->_emxmouse_buttons[2], mouev.col, mouev.row);
268 
269 	      finish:
270 		oldstate = mouev.fs;
271 	    }
272 	} else
273 	    snprintf(err, sizeof(err), "Error setting event mask, buttons=%d, rc=%lu.\r\n",
274 		    nbuttons, rc);
275 
276 	DosWrite(2, err, strlen(err), &rc);
277 	MouClose(hmou);
278     }
279     DosExit(EXIT_THREAD, 0L);
280 }
281 
282 #endif /* USE_EMX_MOUSE */
283 
284 #if USE_SYSMOUSE
285 static void
286 sysmouse_server(SCREEN *sp)
287 {
288     struct mouse_info the_mouse;
289     MEVENT *work;
290 
291     the_mouse.operation = MOUSE_GETINFO;
292     if (sp != 0
293 	&& sp->_mouse_fd >= 0
294 	&& sp->_sysmouse_tail < FIFO_SIZE
295 	&& ioctl(sp->_mouse_fd, CONS_MOUSECTL, &the_mouse) != -1) {
296 
297 	if (sp->_sysmouse_head > sp->_sysmouse_tail) {
298 	    sp->_sysmouse_tail = 0;
299 	    sp->_sysmouse_head = 0;
300 	}
301 	work = &(sp->_sysmouse_fifo[sp->_sysmouse_tail]);
302 	memset(work, 0, sizeof(*work));
303 	work->id = NORMAL_EVENT;	/* there's only one mouse... */
304 
305 	sp->_sysmouse_old_buttons = sp->_sysmouse_new_buttons;
306 	sp->_sysmouse_new_buttons = the_mouse.u.data.buttons & 0x7;
307 
308 	if (sp->_sysmouse_new_buttons) {
309 	    if (sp->_sysmouse_new_buttons & 1)
310 		work->bstate |= BUTTON1_PRESSED;
311 	    if (sp->_sysmouse_new_buttons & 2)
312 		work->bstate |= BUTTON2_PRESSED;
313 	    if (sp->_sysmouse_new_buttons & 4)
314 		work->bstate |= BUTTON3_PRESSED;
315 	} else {
316 	    if (sp->_sysmouse_old_buttons & 1)
317 		work->bstate |= BUTTON1_RELEASED;
318 	    if (sp->_sysmouse_old_buttons & 2)
319 		work->bstate |= BUTTON2_RELEASED;
320 	    if (sp->_sysmouse_old_buttons & 4)
321 		work->bstate |= BUTTON3_RELEASED;
322 	}
323 
324 	/* for cosmetic bug in syscons.c on FreeBSD 3.[34] */
325 	the_mouse.operation = MOUSE_HIDE;
326 	ioctl(sp->_mouse_fd, CONS_MOUSECTL, &the_mouse);
327 	the_mouse.operation = MOUSE_SHOW;
328 	ioctl(sp->_mouse_fd, CONS_MOUSECTL, &the_mouse);
329 
330 	/*
331 	 * We're only interested if the button is pressed or released.
332 	 * FIXME: implement continuous event-tracking.
333 	 */
334 	if (sp->_sysmouse_new_buttons != sp->_sysmouse_old_buttons) {
335 	    sp->_sysmouse_tail += 1;
336 	}
337 	work->x = the_mouse.u.data.x / sp->_sysmouse_char_width;
338 	work->y = the_mouse.u.data.y / sp->_sysmouse_char_height;
339     }
340 }
341 
342 static void
343 handle_sysmouse(int sig GCC_UNUSED)
344 {
345     sysmouse_server(SP);
346 }
347 #endif /* USE_SYSMOUSE */
348 
349 static void
350 init_xterm_mouse(SCREEN *sp)
351 {
352     sp->_mouse_type = M_XTERM;
353     sp->_mouse_xtermcap = tigetstr("XM");
354     if (!VALID_STRING(sp->_mouse_xtermcap))
355 	sp->_mouse_xtermcap = "\033[?1000%?%p1%{1}%=%th%el%;";
356 }
357 
358 static void
359 enable_xterm_mouse(SCREEN *sp, int enable)
360 {
361 #if USE_EMX_MOUSE
362     sp->_emxmouse_activated = enable;
363 #else
364     putp(TPARM_1(sp->_mouse_xtermcap, enable));
365 #endif
366     sp->_mouse_active = enable;
367 }
368 
369 #if USE_GPM_SUPPORT
370 static bool
371 allow_gpm_mouse(void)
372 {
373     bool result = FALSE;
374 
375     /* GPM does printf's without checking if stdout is a terminal */
376     if (isatty(fileno(stdout))) {
377 	char *list = getenv("NCURSES_GPM_TERMS");
378 	char *env = getenv("TERM");
379 	if (list != 0) {
380 	    if (env != 0) {
381 		result = _nc_name_match(list, env, "|:");
382 	    }
383 	} else {
384 	    /* GPM checks the beginning of the $TERM variable to decide if it
385 	     * should pass xterm events through.  There is no real advantage in
386 	     * allowing GPM to do this.  Recent versions relax that check, and
387 	     * pretend that GPM can work with any terminal having the kmous
388 	     * capability.  Perhaps that works for someone.  If so, they can
389 	     * set the environment variable (above).
390 	     */
391 	    if (env != 0 && strstr(env, "linux") != 0) {
392 		result = TRUE;
393 	    }
394 	}
395     }
396     return result;
397 }
398 
399 #ifdef HAVE_LIBDL
400 static void
401 unload_gpm_library(SCREEN *sp)
402 {
403     if (SP->_dlopen_gpm != 0) {
404 	T(("unload GPM library"));
405 	sp->_mouse_gpm_loaded = FALSE;
406 	sp->_mouse_fd = -1;
407 	dlclose(sp->_dlopen_gpm);
408 	sp->_dlopen_gpm = 0;
409     }
410 }
411 
412 static void
413 load_gpm_library(SCREEN *sp)
414 {
415     sp->_mouse_gpm_found = FALSE;
416     if ((sp->_dlopen_gpm = dlopen(LIBGPM_SONAME, my_RTLD)) != 0) {
417 	if (GET_DLSYM(gpm_fd) == 0 ||
418 	    GET_DLSYM(Gpm_Open) == 0 ||
419 	    GET_DLSYM(Gpm_Close) == 0 ||
420 	    GET_DLSYM(Gpm_GetEvent) == 0) {
421 	    T(("GPM initialization failed: %s", dlerror()));
422 	    unload_gpm_library(sp);
423 	} else {
424 	    sp->_mouse_gpm_found = TRUE;
425 	    sp->_mouse_gpm_loaded = TRUE;
426 	}
427     }
428 }
429 #endif
430 
431 static bool
432 enable_gpm_mouse(SCREEN *sp, bool enable)
433 {
434     bool result;
435 
436     T((T_CALLED("enable_gpm_mouse(%d)"), enable));
437 
438     if (enable && !sp->_mouse_active) {
439 #ifdef HAVE_LIBDL
440 	if (sp->_mouse_gpm_found && !sp->_mouse_gpm_loaded) {
441 	    load_gpm_library(sp);
442 	}
443 #endif
444 	if (sp->_mouse_gpm_loaded) {
445 	    /* GPM: initialize connection to gpm server */
446 	    sp->_mouse_gpm_connect.eventMask = GPM_DOWN | GPM_UP;
447 	    sp->_mouse_gpm_connect.defaultMask =
448 		(unsigned short) (~(sp->_mouse_gpm_connect.eventMask | GPM_HARD));
449 	    sp->_mouse_gpm_connect.minMod = 0;
450 	    sp->_mouse_gpm_connect.maxMod =
451 		(unsigned short) (~((1 << KG_SHIFT) |
452 				    (1 << KG_SHIFTL) |
453 				    (1 << KG_SHIFTR)));
454 	    /*
455 	     * Note: GPM hardcodes \E[?1001s and \E[?1000h during its open.
456 	     * The former is recognized by wscons (SunOS), and the latter by
457 	     * xterm.  Those will not show up in ncurses' traces.
458 	     */
459 	    result = (my_Gpm_Open(&sp->_mouse_gpm_connect, 0) >= 0);
460 	} else {
461 	    result = FALSE;
462 	}
463 	sp->_mouse_active = result;
464 	T(("GPM open %s", result ? "succeeded" : "failed"));
465     } else {
466 	if (!enable && sp->_mouse_active) {
467 	    /* GPM: close connection to gpm server */
468 	    my_Gpm_Close();
469 	    sp->_mouse_active = FALSE;
470 	    T(("GPM closed"));
471 	}
472 	result = enable;
473     }
474 #ifdef HAVE_LIBDL
475     if (!result) {
476 	unload_gpm_library(sp);
477     }
478 #endif
479     returnBool(result);
480 }
481 #endif /* USE_GPM_SUPPORT */
482 
483 #define xterm_kmous "\033[M"
484 
485 static void
486 initialize_mousetype(SCREEN *sp)
487 {
488     T((T_CALLED("initialize_mousetype()")));
489 
490     /* Try gpm first, because gpm may be configured to run in xterm */
491 #if USE_GPM_SUPPORT
492     if (allow_gpm_mouse()) {
493 	if (!sp->_mouse_gpm_loaded) {
494 #ifdef HAVE_LIBDL
495 	    load_gpm_library(sp);
496 #else /* !HAVE_LIBDL */
497 	    sp->_mouse_gpm_found = TRUE;
498 	    sp->_mouse_gpm_loaded = TRUE;
499 #endif
500 	}
501 
502 	/*
503 	 * The gpm_fd file-descriptor may be negative (xterm).  So we have to
504 	 * maintain our notion of whether the mouse connection is active
505 	 * without testing the file-descriptor.
506 	 */
507 	if (sp->_mouse_gpm_found && enable_gpm_mouse(sp, TRUE)) {
508 	    sp->_mouse_type = M_GPM;
509 	    sp->_mouse_fd = *(my_gpm_fd);
510 	    T(("GPM mouse_fd %d", sp->_mouse_fd));
511 	    returnVoid;
512 	}
513     }
514 #endif /* USE_GPM_SUPPORT */
515 
516     /* OS/2 VIO */
517 #if USE_EMX_MOUSE
518     if (!sp->_emxmouse_thread
519 	&& strstr(cur_term->type.term_names, "xterm") == 0
520 	&& key_mouse) {
521 	int handles[2];
522 
523 	if (pipe(handles) < 0) {
524 	    perror("mouse pipe error");
525 	    returnVoid;
526 	} else {
527 	    int rc;
528 
529 	    if (!sp->_emxmouse_buttons[0]) {
530 		char *s = getenv("MOUSE_BUTTONS_123");
531 
532 		sp->_emxmouse_buttons[0] = 1;
533 		if (s && strlen(s) >= 3) {
534 		    sp->_emxmouse_buttons[1] = s[0] - '0';
535 		    sp->_emxmouse_buttons[2] = s[1] - '0';
536 		    sp->_emxmouse_buttons[3] = s[2] - '0';
537 		} else {
538 		    sp->_emxmouse_buttons[1] = 1;
539 		    sp->_emxmouse_buttons[2] = 3;
540 		    sp->_emxmouse_buttons[3] = 2;
541 		}
542 	    }
543 	    sp->_emxmouse_wfd = handles[1];
544 	    M_FD(sp) = handles[0];
545 	    /* Needed? */
546 	    setmode(handles[0], O_BINARY);
547 	    setmode(handles[1], O_BINARY);
548 	    /* Do not use CRT functions, we may single-threaded. */
549 	    rc = DosCreateThread((unsigned long *) &sp->_emxmouse_thread,
550 				 mouse_server, (long) sp, 0, 8192);
551 	    if (rc) {
552 		printf("mouse thread error %d=%#x", rc, rc);
553 	    } else {
554 		sp->_mouse_type = M_XTERM;
555 	    }
556 	    returnVoid;
557 	}
558     }
559 #endif /* USE_EMX_MOUSE */
560 
561 #if USE_SYSMOUSE
562     {
563 	struct mouse_info the_mouse;
564 	char *the_device = 0;
565 
566 	if (isatty(sp->_ifd))
567 	    the_device = ttyname(sp->_ifd);
568 	if (the_device == 0)
569 	    the_device = "/dev/tty";
570 
571 	sp->_mouse_fd = open(the_device, O_RDWR);
572 
573 	if (sp->_mouse_fd >= 0) {
574 	    /*
575 	     * sysmouse does not have a usable user interface for obtaining
576 	     * mouse events.  The logical way to proceed (reading data on a
577 	     * stream) only works if one opens the device as root.  Even in
578 	     * that mode, careful examination shows we lose events
579 	     * occasionally.  The interface provided for user programs is to
580 	     * establish a signal handler.  really.
581 	     *
582 	     * Take over SIGUSR2 for this purpose since SIGUSR1 is more
583 	     * likely to be used by an application.  getch() will have to
584 	     * handle the misleading EINTR's.
585 	     */
586 	    signal(SIGUSR2, SIG_IGN);
587 	    the_mouse.operation = MOUSE_MODE;
588 	    the_mouse.u.mode.mode = 0;
589 	    the_mouse.u.mode.signal = SIGUSR2;
590 	    if (ioctl(sp->_mouse_fd, CONS_MOUSECTL, &the_mouse) != -1) {
591 		signal(SIGUSR2, handle_sysmouse);
592 		the_mouse.operation = MOUSE_SHOW;
593 		ioctl(sp->_mouse_fd, CONS_MOUSECTL, &the_mouse);
594 
595 #if defined(FBIO_MODEINFO) || defined(CONS_MODEINFO)	/* FreeBSD > 2.x */
596 		{
597 #ifndef FBIO_GETMODE		/* FreeBSD 3.x */
598 #define FBIO_GETMODE    CONS_GET
599 #define FBIO_MODEINFO   CONS_MODEINFO
600 #endif /* FBIO_GETMODE */
601 		    video_info_t the_video;
602 
603 		    if (ioctl(sp->_mouse_fd,
604 			      FBIO_GETMODE,
605 			      &the_video.vi_mode) != -1
606 			&& ioctl(sp->_mouse_fd,
607 				 FBIO_MODEINFO,
608 				 &the_video) != -1) {
609 			sp->_sysmouse_char_width = the_video.vi_cwidth;
610 			sp->_sysmouse_char_height = the_video.vi_cheight;
611 		    }
612 		}
613 #endif /* defined(FBIO_MODEINFO) || defined(CONS_MODEINFO) */
614 
615 		if (sp->_sysmouse_char_width <= 0)
616 		    sp->_sysmouse_char_width = 8;
617 		if (sp->_sysmouse_char_height <= 0)
618 		    sp->_sysmouse_char_height = 16;
619 		sp->_mouse_type = M_SYSMOUSE;
620 		returnVoid;
621 	    }
622 	}
623     }
624 #endif /* USE_SYSMOUSE */
625 
626     /* we know how to recognize mouse events under "xterm" */
627     if (key_mouse != 0) {
628 	if (!strcmp(key_mouse, xterm_kmous)
629 	    || strstr(cur_term->type.term_names, "xterm") != 0) {
630 	    init_xterm_mouse(sp);
631 	}
632     } else if (strstr(cur_term->type.term_names, "xterm") != 0) {
633 	if (_nc_add_to_try(&(sp->_keytry), xterm_kmous, KEY_MOUSE) == OK)
634 	    init_xterm_mouse(sp);
635     }
636     returnVoid;
637 }
638 
639 static bool
640 _nc_mouse_init(SCREEN *sp)
641 /* initialize the mouse */
642 {
643     bool result = FALSE;
644     int i;
645 
646     if (sp != 0) {
647 	if (!sp->_mouse_initialized) {
648 	    sp->_mouse_initialized = TRUE;
649 
650 	    TR(MY_TRACE, ("_nc_mouse_init() called"));
651 
652 	    sp->_mouse_eventp = FirstEV(sp);
653 	    for (i = 0; i < EV_MAX; i++)
654 		sp->_mouse_events[i].id = INVALID_EVENT;
655 
656 	    initialize_mousetype(sp);
657 
658 	    T(("_nc_mouse_init() set mousetype to %d", sp->_mouse_type));
659 	}
660 	result = sp->_mouse_initialized;
661     }
662     return result;
663 }
664 
665 /*
666  * Query to see if there is a pending mouse event.  This is called from
667  * fifo_push() in lib_getch.c
668  */
669 static bool
670 _nc_mouse_event(SCREEN *sp GCC_UNUSED)
671 {
672     MEVENT *eventp = sp->_mouse_eventp;
673     bool result = FALSE;
674 
675     (void) eventp;
676 
677     switch (sp->_mouse_type) {
678     case M_XTERM:
679 	/* xterm: never have to query, mouse events are in the keyboard stream */
680 #if USE_EMX_MOUSE
681 	{
682 	    char kbuf[3];
683 
684 	    int i, res = read(M_FD(sp), &kbuf, 3);	/* Eat the prefix */
685 	    if (res != 3)
686 		printf("Got %d chars instead of 3 for prefix.\n", res);
687 	    for (i = 0; i < res; i++) {
688 		if (kbuf[i] != key_mouse[i])
689 		    printf("Got char %d instead of %d for prefix.\n",
690 			   (int) kbuf[i], (int) key_mouse[i]);
691 	    }
692 	    result = TRUE;
693 	}
694 #endif /* USE_EMX_MOUSE */
695 	break;
696 
697 #if USE_GPM_SUPPORT
698     case M_GPM:
699 	{
700 	    /* query server for event, return TRUE if we find one */
701 	    Gpm_Event ev;
702 
703 	    if (my_Gpm_GetEvent(&ev) == 1) {
704 		/* there's only one mouse... */
705 		eventp->id = NORMAL_EVENT;
706 
707 		eventp->bstate = 0;
708 		switch (ev.type & 0x0f) {
709 		case (GPM_DOWN):
710 		    if (ev.buttons & GPM_B_LEFT)
711 			eventp->bstate |= BUTTON1_PRESSED;
712 		    if (ev.buttons & GPM_B_MIDDLE)
713 			eventp->bstate |= BUTTON2_PRESSED;
714 		    if (ev.buttons & GPM_B_RIGHT)
715 			eventp->bstate |= BUTTON3_PRESSED;
716 		    break;
717 		case (GPM_UP):
718 		    if (ev.buttons & GPM_B_LEFT)
719 			eventp->bstate |= BUTTON1_RELEASED;
720 		    if (ev.buttons & GPM_B_MIDDLE)
721 			eventp->bstate |= BUTTON2_RELEASED;
722 		    if (ev.buttons & GPM_B_RIGHT)
723 			eventp->bstate |= BUTTON3_RELEASED;
724 		    break;
725 		default:
726 		    break;
727 		}
728 
729 		eventp->x = ev.x - 1;
730 		eventp->y = ev.y - 1;
731 		eventp->z = 0;
732 
733 		/* bump the next-free pointer into the circular list */
734 		sp->_mouse_eventp = eventp = NEXT(eventp);
735 		result = TRUE;
736 	    }
737 	}
738 	break;
739 #endif
740 
741 #if USE_SYSMOUSE
742     case M_SYSMOUSE:
743 	if (sp->_sysmouse_head < sp->_sysmouse_tail) {
744 	    *eventp = sp->_sysmouse_fifo[sp->_sysmouse_head];
745 
746 	    /*
747 	     * Point the fifo-head to the next possible location.  If there
748 	     * are none, reset the indices.  This may be interrupted by the
749 	     * signal handler, doing essentially the same reset.
750 	     */
751 	    sp->_sysmouse_head += 1;
752 	    if (sp->_sysmouse_head == sp->_sysmouse_tail) {
753 		sp->_sysmouse_tail = 0;
754 		sp->_sysmouse_head = 0;
755 	    }
756 
757 	    /* bump the next-free pointer into the circular list */
758 	    sp->_mouse_eventp = eventp = NEXT(eventp);
759 	    result = TRUE;
760 	}
761 	break;
762 #endif /* USE_SYSMOUSE */
763 
764     case M_NONE:
765 	break;
766     }
767 
768     return result;		/* true if we found an event */
769 }
770 
771 static bool
772 _nc_mouse_inline(SCREEN *sp)
773 /* mouse report received in the keyboard stream -- parse its info */
774 {
775     int b;
776     bool result = FALSE;
777     MEVENT *eventp = sp->_mouse_eventp;
778 
779     TR(MY_TRACE, ("_nc_mouse_inline() called"));
780 
781     if (sp->_mouse_type == M_XTERM) {
782 	unsigned char kbuf[4];
783 	mmask_t prev;
784 	size_t grabbed;
785 	int res;
786 
787 	/* This code requires that your xterm entry contain the kmous
788 	 * capability and that it be set to the \E[M documented in the
789 	 * Xterm Control Sequences reference.  This is how we
790 	 * arrange for mouse events to be reported via a KEY_MOUSE
791 	 * return value from wgetch().  After this value is received,
792 	 * _nc_mouse_inline() gets called and is immediately
793 	 * responsible for parsing the mouse status information
794 	 * following the prefix.
795 	 *
796 	 * The following quotes from the ctrlseqs.ms document in the
797 	 * X distribution, describing the X mouse tracking feature:
798 	 *
799 	 * Parameters for all mouse tracking escape sequences
800 	 * generated by xterm encode numeric parameters in a single
801 	 * character as value+040.  For example, !  is 1.
802 	 *
803 	 * On button press or release, xterm sends ESC [ M CbCxCy.
804 	 * The low two bits of Cb encode button information: 0=MB1
805 	 * pressed, 1=MB2 pressed, 2=MB3 pressed, 3=release.  The
806 	 * upper bits encode what modifiers were down when the
807 	 * button was pressed and are added together.  4=Shift,
808 	 * 8=Meta, 16=Control.  Cx and Cy are the x and y coordinates
809 	 * of the mouse event.  The upper left corner is (1,1).
810 	 *
811 	 * (End quote)  By the time we get here, we've eaten the
812 	 * key prefix.  FYI, the loop below is necessary because
813 	 * mouse click info isn't guaranteed to present as a
814 	 * single clist item.
815 	 *
816 	 * Wheel mice may return buttons 4 and 5 when the wheel is turned.
817 	 * We encode those as button presses.
818 	 */
819 	for (grabbed = 0; grabbed < 3; grabbed += (size_t) res) {
820 
821 	    /* For VIO mouse we add extra bit 64 to disambiguate button-up. */
822 #if USE_EMX_MOUSE
823 	    res = read(M_FD(sp) >= 0 ? M_FD(sp) : sp->_ifd, &kbuf, 3);
824 #else
825 	    res = read(sp->_ifd, kbuf + grabbed, 3 - grabbed);
826 #endif
827 	    if (res == -1)
828 		break;
829 	}
830 	kbuf[3] = '\0';
831 
832 	TR(TRACE_IEVENT,
833 	   ("_nc_mouse_inline sees the following xterm data: '%s'", kbuf));
834 
835 	/* there's only one mouse... */
836 	eventp->id = NORMAL_EVENT;
837 
838 	/* processing code goes here */
839 	eventp->bstate = 0;
840 	prev = PREV(eventp)->bstate;
841 
842 #if USE_EMX_MOUSE
843 #define PRESS_POSITION(n) \
844 	eventp->bstate = MASK_PRESS(n); \
845 	if (kbuf[0] & 0x40) \
846 	    eventp->bstate = MASK_RELEASE(n)
847 #else
848 #define PRESS_POSITION(n) \
849 	eventp->bstate = (mmask_t) (prev & MASK_PRESS(n) \
850 				    ? REPORT_MOUSE_POSITION \
851 				    : MASK_PRESS(n))
852 #endif
853 
854 	switch (kbuf[0] & 0x3) {
855 	case 0x0:
856 	    if (kbuf[0] & 64)
857 		eventp->bstate = MASK_PRESS(4);
858 	    else
859 		PRESS_POSITION(1);
860 	    break;
861 
862 	case 0x1:
863 #if NCURSES_MOUSE_VERSION == 2
864 	    if (kbuf[0] & 64)
865 		eventp->bstate = MASK_PRESS(5);
866 	    else
867 #endif
868 		PRESS_POSITION(2);
869 	    break;
870 
871 	case 0x2:
872 	    PRESS_POSITION(3);
873 	    break;
874 
875 	case 0x3:
876 	    /*
877 	     * Release events aren't reported for individual buttons, just for
878 	     * the button set as a whole.  However, because there are normally
879 	     * no mouse events under xterm that intervene between press and
880 	     * release, we can infer the button actually released by looking at
881 	     * the previous event.
882 	     */
883 	    if (prev & (BUTTON_PRESSED | BUTTON_RELEASED)) {
884 		eventp->bstate = BUTTON_RELEASED;
885 		for (b = 1; b <= MAX_BUTTONS; ++b) {
886 		    if (!(prev & MASK_PRESS(b)))
887 			eventp->bstate &= ~MASK_RELEASE(b);
888 		}
889 	    } else {
890 		/*
891 		 * XFree86 xterm will return a stream of release-events to
892 		 * let the application know where the mouse is going, if the
893 		 * private mode 1002 or 1003 is enabled.
894 		 */
895 		eventp->bstate = REPORT_MOUSE_POSITION;
896 	    }
897 	    break;
898 	}
899 	result = (eventp->bstate & REPORT_MOUSE_POSITION) ? TRUE : FALSE;
900 
901 	if (kbuf[0] & 4) {
902 	    eventp->bstate |= BUTTON_SHIFT;
903 	}
904 	if (kbuf[0] & 8) {
905 	    eventp->bstate |= BUTTON_ALT;
906 	}
907 	if (kbuf[0] & 16) {
908 	    eventp->bstate |= BUTTON_CTRL;
909 	}
910 
911 	eventp->x = (kbuf[1] - ' ') - 1;
912 	eventp->y = (kbuf[2] - ' ') - 1;
913 	TR(MY_TRACE,
914 	   ("_nc_mouse_inline: primitive mouse-event %s has slot %ld",
915 	    _nc_tracemouse(sp, eventp),
916 	    (long) IndexEV(sp, eventp)));
917 
918 	/* bump the next-free pointer into the circular list */
919 	sp->_mouse_eventp = NEXT(eventp);
920 #if 0				/* this return would be needed for QNX's mods to lib_getch.c */
921 	return (TRUE);
922 #endif
923     }
924 
925     return (result);
926 }
927 
928 static void
929 mouse_activate(SCREEN *sp, bool on)
930 {
931     if (!on && !sp->_mouse_initialized)
932 	return;
933 
934     if (!_nc_mouse_init(sp))
935 	return;
936 
937     if (on) {
938 
939 	switch (sp->_mouse_type) {
940 	case M_XTERM:
941 #if NCURSES_EXT_FUNCS
942 	    keyok(KEY_MOUSE, on);
943 #endif
944 	    TPUTS_TRACE("xterm mouse initialization");
945 	    enable_xterm_mouse(sp, 1);
946 	    break;
947 #if USE_GPM_SUPPORT
948 	case M_GPM:
949 	    if (enable_gpm_mouse(sp, TRUE)) {
950 		sp->_mouse_fd = *(my_gpm_fd);
951 		T(("GPM mouse_fd %d", sp->_mouse_fd));
952 	    }
953 	    break;
954 #endif
955 #if USE_SYSMOUSE
956 	case M_SYSMOUSE:
957 	    signal(SIGUSR2, handle_sysmouse);
958 	    sp->_mouse_active = TRUE;
959 	    break;
960 #endif
961 	case M_NONE:
962 	    return;
963 	}
964 	/* Make runtime binding to cut down on object size of applications that
965 	 * do not use the mouse (e.g., 'clear').
966 	 */
967 	sp->_mouse_event = _nc_mouse_event;
968 	sp->_mouse_inline = _nc_mouse_inline;
969 	sp->_mouse_parse = _nc_mouse_parse;
970 	sp->_mouse_resume = _nc_mouse_resume;
971 	sp->_mouse_wrap = _nc_mouse_wrap;
972     } else {
973 
974 	switch (sp->_mouse_type) {
975 	case M_XTERM:
976 	    TPUTS_TRACE("xterm mouse deinitialization");
977 	    enable_xterm_mouse(sp, 0);
978 	    break;
979 #if USE_GPM_SUPPORT
980 	case M_GPM:
981 	    enable_gpm_mouse(sp, FALSE);
982 	    break;
983 #endif
984 #if USE_SYSMOUSE
985 	case M_SYSMOUSE:
986 	    signal(SIGUSR2, SIG_IGN);
987 	    sp->_mouse_active = FALSE;
988 	    break;
989 #endif
990 	case M_NONE:
991 	    return;
992 	}
993     }
994     _nc_flush();
995 }
996 
997 /**************************************************************************
998  *
999  * Device-independent code
1000  *
1001  **************************************************************************/
1002 
1003 static bool
1004 _nc_mouse_parse(SCREEN *sp, int runcount)
1005 /* parse a run of atomic mouse events into a gesture */
1006 {
1007     MEVENT *eventp = sp->_mouse_eventp;
1008     MEVENT *ep, *runp, *next, *prev = PREV(eventp);
1009     int n;
1010     int b;
1011     bool merge;
1012 
1013     TR(MY_TRACE, ("_nc_mouse_parse(%d) called", runcount));
1014 
1015     /*
1016      * When we enter this routine, the event list next-free pointer
1017      * points just past a run of mouse events that we know were separated
1018      * in time by less than the critical click interval. The job of this
1019      * routine is to collapse this run into a single higher-level event
1020      * or gesture.
1021      *
1022      * We accomplish this in two passes.  The first pass merges press/release
1023      * pairs into click events.  The second merges runs of click events into
1024      * double or triple-click events.
1025      *
1026      * It's possible that the run may not resolve to a single event (for
1027      * example, if the user quadruple-clicks).  If so, leading events
1028      * in the run are ignored.
1029      *
1030      * Note that this routine is independent of the format of the specific
1031      * format of the pointing-device's reports.  We can use it to parse
1032      * gestures on anything that reports press/release events on a per-
1033      * button basis, as long as the device-dependent mouse code puts stuff
1034      * on the queue in MEVENT format.
1035      */
1036     if (runcount == 1) {
1037 	TR(MY_TRACE,
1038 	   ("_nc_mouse_parse: returning simple mouse event %s at slot %ld",
1039 	    _nc_tracemouse(sp, prev),
1040 	    (long) IndexEV(sp, prev)));
1041 	return (prev->id >= NORMAL_EVENT)
1042 	    ? ((prev->bstate & sp->_mouse_mask) ? TRUE : FALSE)
1043 	    : FALSE;
1044     }
1045 
1046     /* find the start of the run */
1047     runp = eventp;
1048     for (n = runcount; n > 0; n--) {
1049 	runp = PREV(runp);
1050     }
1051 
1052 #ifdef TRACE
1053     if (USE_TRACEF(TRACE_IEVENT)) {
1054 	_trace_slot(sp, "before mouse press/release merge:");
1055 	_tracef("_nc_mouse_parse: run starts at %ld, ends at %ld, count %d",
1056 		RunParams(sp, eventp, runp),
1057 		runcount);
1058 	_nc_unlock_global(tracef);
1059     }
1060 #endif /* TRACE */
1061 
1062     /* first pass; merge press/release pairs */
1063     do {
1064 	merge = FALSE;
1065 	for (ep = runp; (next = NEXT(ep)) != eventp; ep = next) {
1066 
1067 #define MASK_CHANGED(x) (!(ep->bstate & MASK_PRESS(x)) \
1068 		      == !(next->bstate & MASK_RELEASE(x)))
1069 
1070 	    if (ep->x == next->x && ep->y == next->y
1071 		&& (ep->bstate & BUTTON_PRESSED)
1072 		&& MASK_CHANGED(1)
1073 		&& MASK_CHANGED(2)
1074 		&& MASK_CHANGED(3)
1075 		&& MASK_CHANGED(4)
1076 #if NCURSES_MOUSE_VERSION == 2
1077 		&& MASK_CHANGED(5)
1078 #endif
1079 		) {
1080 		for (b = 1; b <= MAX_BUTTONS; ++b) {
1081 		    if ((sp->_mouse_mask & MASK_CLICK(b))
1082 			&& (ep->bstate & MASK_PRESS(b))) {
1083 			ep->bstate &= ~MASK_PRESS(b);
1084 			ep->bstate |= MASK_CLICK(b);
1085 			merge = TRUE;
1086 		    }
1087 		}
1088 		if (merge)
1089 		    next->id = INVALID_EVENT;
1090 	    }
1091 	}
1092     } while
1093 	(merge);
1094 
1095 #ifdef TRACE
1096     if (USE_TRACEF(TRACE_IEVENT)) {
1097 	_trace_slot(sp, "before mouse click merge:");
1098 	_tracef("_nc_mouse_parse: run starts at %ld, ends at %ld, count %d",
1099 		RunParams(sp, eventp, runp),
1100 		runcount);
1101 	_nc_unlock_global(tracef);
1102     }
1103 #endif /* TRACE */
1104 
1105     /*
1106      * Second pass; merge click runs.  At this point, click events are
1107      * each followed by one invalid event. We merge click events
1108      * forward in the queue.
1109      *
1110      * NOTE: There is a problem with this design!  If the application
1111      * allows enough click events to pile up in the circular queue so
1112      * they wrap around, it will cheerfully merge the newest forward
1113      * into the oldest, creating a bogus doubleclick and confusing
1114      * the queue-traversal logic rather badly.  Generally this won't
1115      * happen, because calling getmouse() marks old events invalid and
1116      * ineligible for merges.  The true solution to this problem would
1117      * be to timestamp each MEVENT and perform the obvious sanity check,
1118      * but the timer element would have to have sub-second resolution,
1119      * which would get us into portability trouble.
1120      */
1121     do {
1122 	MEVENT *follower;
1123 
1124 	merge = FALSE;
1125 	for (ep = runp; (next = NEXT(ep)) != eventp; ep = next)
1126 	    if (ep->id != INVALID_EVENT) {
1127 		if (next->id != INVALID_EVENT)
1128 		    continue;
1129 		follower = NEXT(next);
1130 		if (follower->id == INVALID_EVENT)
1131 		    continue;
1132 
1133 		/* merge click events forward */
1134 		if ((ep->bstate & BUTTON_CLICKED)
1135 		    && (follower->bstate & BUTTON_CLICKED)) {
1136 		    for (b = 1; b <= MAX_BUTTONS; ++b) {
1137 			if ((sp->_mouse_mask & MASK_DOUBLE_CLICK(b))
1138 			    && (follower->bstate & MASK_CLICK(b))) {
1139 			    follower->bstate &= ~MASK_CLICK(b);
1140 			    follower->bstate |= MASK_DOUBLE_CLICK(b);
1141 			    merge = TRUE;
1142 			}
1143 		    }
1144 		    if (merge)
1145 			ep->id = INVALID_EVENT;
1146 		}
1147 
1148 		/* merge double-click events forward */
1149 		if ((ep->bstate & BUTTON_DOUBLE_CLICKED)
1150 		    && (follower->bstate & BUTTON_CLICKED)) {
1151 		    for (b = 1; b <= MAX_BUTTONS; ++b) {
1152 			if ((sp->_mouse_mask & MASK_TRIPLE_CLICK(b))
1153 			    && (follower->bstate & MASK_CLICK(b))) {
1154 			    follower->bstate &= ~MASK_CLICK(b);
1155 			    follower->bstate |= MASK_TRIPLE_CLICK(b);
1156 			    merge = TRUE;
1157 			}
1158 		    }
1159 		    if (merge)
1160 			ep->id = INVALID_EVENT;
1161 		}
1162 	    }
1163     } while
1164 	(merge);
1165 
1166 #ifdef TRACE
1167     if (USE_TRACEF(TRACE_IEVENT)) {
1168 	_trace_slot(sp, "before mouse event queue compaction:");
1169 	_tracef("_nc_mouse_parse: run starts at %ld, ends at %ld, count %d",
1170 		RunParams(sp, eventp, runp),
1171 		runcount);
1172 	_nc_unlock_global(tracef);
1173     }
1174 #endif /* TRACE */
1175 
1176     /*
1177      * Now try to throw away trailing events flagged invalid, or that
1178      * don't match the current event mask.
1179      */
1180     for (; runcount; prev = PREV(eventp), runcount--)
1181 	if (prev->id == INVALID_EVENT || !(prev->bstate & sp->_mouse_mask)) {
1182 	    sp->_mouse_eventp = eventp = prev;
1183 	}
1184 #ifdef TRACE
1185     if (USE_TRACEF(TRACE_IEVENT)) {
1186 	_trace_slot(sp, "after mouse event queue compaction:");
1187 	_tracef("_nc_mouse_parse: run starts at %ld, ends at %ld, count %d",
1188 		RunParams(sp, eventp, runp),
1189 		runcount);
1190 	_nc_unlock_global(tracef);
1191     }
1192     for (ep = runp; ep != eventp; ep = NEXT(ep))
1193 	if (ep->id != INVALID_EVENT)
1194 	    TR(MY_TRACE,
1195 	       ("_nc_mouse_parse: returning composite mouse event %s at slot %ld",
1196 		_nc_tracemouse(sp, ep),
1197 		(long) IndexEV(sp, ep)));
1198 #endif /* TRACE */
1199 
1200     /* after all this, do we have a valid event? */
1201     return (PREV(eventp)->id != INVALID_EVENT);
1202 }
1203 
1204 static void
1205 _nc_mouse_wrap(SCREEN *sp)
1206 /* release mouse -- called by endwin() before shellout/exit */
1207 {
1208     TR(MY_TRACE, ("_nc_mouse_wrap() called"));
1209 
1210     switch (sp->_mouse_type) {
1211     case M_XTERM:
1212 	if (sp->_mouse_mask)
1213 	    mouse_activate(sp, FALSE);
1214 	break;
1215 #if USE_GPM_SUPPORT
1216 	/* GPM: pass all mouse events to next client */
1217     case M_GPM:
1218 	if (sp->_mouse_mask)
1219 	    mouse_activate(sp, FALSE);
1220 	break;
1221 #endif
1222 #if USE_SYSMOUSE
1223     case M_SYSMOUSE:
1224 	mouse_activate(sp, FALSE);
1225 	break;
1226 #endif
1227     case M_NONE:
1228 	break;
1229     }
1230 }
1231 
1232 static void
1233 _nc_mouse_resume(SCREEN *sp)
1234 /* re-connect to mouse -- called by doupdate() after shellout */
1235 {
1236     TR(MY_TRACE, ("_nc_mouse_resume() called"));
1237 
1238     switch (sp->_mouse_type) {
1239     case M_XTERM:
1240 	/* xterm: re-enable reporting */
1241 	if (sp->_mouse_mask)
1242 	    mouse_activate(sp, TRUE);
1243 	break;
1244 
1245 #if USE_GPM_SUPPORT
1246     case M_GPM:
1247 	/* GPM: reclaim our event set */
1248 	if (sp->_mouse_mask)
1249 	    mouse_activate(sp, TRUE);
1250 	break;
1251 #endif
1252 
1253 #if USE_SYSMOUSE
1254     case M_SYSMOUSE:
1255 	mouse_activate(sp, TRUE);
1256 	break;
1257 #endif
1258     case M_NONE:
1259 	break;
1260     }
1261 }
1262 
1263 /**************************************************************************
1264  *
1265  * Mouse interface entry points for the API
1266  *
1267  **************************************************************************/
1268 
1269 static int
1270 _nc_getmouse(SCREEN *sp, MEVENT * aevent)
1271 {
1272     T((T_CALLED("getmouse(%p)"), aevent));
1273 
1274     if ((aevent != 0) && (sp != 0) && (sp->_mouse_type != M_NONE)) {
1275 	MEVENT *eventp = sp->_mouse_eventp;
1276 	/* compute the current-event pointer */
1277 	MEVENT *prev = PREV(eventp);
1278 
1279 	/* copy the event we find there */
1280 	*aevent = *prev;
1281 
1282 	TR(TRACE_IEVENT, ("getmouse: returning event %s from slot %ld",
1283 			  _nc_tracemouse(sp, prev),
1284 			  (long) IndexEV(sp, prev)));
1285 
1286 	prev->id = INVALID_EVENT;	/* so the queue slot becomes free */
1287 	returnCode(OK);
1288     }
1289     returnCode(ERR);
1290 }
1291 
1292 /* grab a copy of the current mouse event */
1293 NCURSES_EXPORT(int)
1294 getmouse(MEVENT * aevent)
1295 {
1296     return _nc_getmouse(SP, aevent);
1297 }
1298 
1299 static int
1300 _nc_ungetmouse(SCREEN *sp, MEVENT * aevent)
1301 {
1302     int result = ERR;
1303 
1304     T((T_CALLED("ungetmouse(%p)"), aevent));
1305 
1306     if (aevent != 0 && sp != 0) {
1307 	MEVENT *eventp = sp->_mouse_eventp;
1308 
1309 	/* stick the given event in the next-free slot */
1310 	*eventp = *aevent;
1311 
1312 	/* bump the next-free pointer into the circular list */
1313 	sp->_mouse_eventp = NEXT(eventp);
1314 
1315 	/* push back the notification event on the keyboard queue */
1316 	result = _nc_ungetch(sp, KEY_MOUSE);
1317     }
1318     returnCode(result);
1319 }
1320 
1321 /* enqueue a synthesized mouse event to be seen by the next wgetch() */
1322 NCURSES_EXPORT(int)
1323 ungetmouse(MEVENT * aevent)
1324 {
1325     return _nc_ungetmouse(SP, aevent);
1326 }
1327 
1328 NCURSES_EXPORT(mmask_t)
1329 mousemask(mmask_t newmask, mmask_t * oldmask)
1330 /* set the mouse event mask */
1331 {
1332     mmask_t result = 0;
1333 
1334     T((T_CALLED("mousemask(%#lx,%p)"), (unsigned long) newmask, oldmask));
1335 
1336     if (SP != 0) {
1337 	if (oldmask)
1338 	    *oldmask = SP->_mouse_mask;
1339 
1340 	if (newmask || SP->_mouse_initialized) {
1341 	    _nc_mouse_init(SP);
1342 	    if (SP->_mouse_type != M_NONE) {
1343 		result = newmask &
1344 		    (REPORT_MOUSE_POSITION
1345 		     | BUTTON_ALT
1346 		     | BUTTON_CTRL
1347 		     | BUTTON_SHIFT
1348 		     | BUTTON_PRESSED
1349 		     | BUTTON_RELEASED
1350 		     | BUTTON_CLICKED
1351 		     | BUTTON_DOUBLE_CLICKED
1352 		     | BUTTON_TRIPLE_CLICKED);
1353 
1354 		mouse_activate(SP, (bool) (result != 0));
1355 
1356 		SP->_mouse_mask = result;
1357 	    }
1358 	}
1359     }
1360     returnBits(result);
1361 }
1362 
1363 NCURSES_EXPORT(bool)
1364 wenclose(const WINDOW *win, int y, int x)
1365 /* check to see if given window encloses given screen location */
1366 {
1367     bool result = FALSE;
1368 
1369     T((T_CALLED("wenclose(%p,%d,%d)"), win, y, x));
1370 
1371     if (win != 0) {
1372 	y -= win->_yoffset;
1373 	result = ((win->_begy <= y &&
1374 		   win->_begx <= x &&
1375 		   (win->_begx + win->_maxx) >= x &&
1376 		   (win->_begy + win->_maxy) >= y) ? TRUE : FALSE);
1377     }
1378     returnBool(result);
1379 }
1380 
1381 NCURSES_EXPORT(int)
1382 mouseinterval(int maxclick)
1383 /* set the maximum mouse interval within which to recognize a click */
1384 {
1385     int oldval;
1386 
1387     T((T_CALLED("mouseinterval(%d)"), maxclick));
1388 
1389     if (SP != 0) {
1390 	oldval = SP->_maxclick;
1391 	if (maxclick >= 0)
1392 	    SP->_maxclick = maxclick;
1393     } else {
1394 	oldval = DEFAULT_MAXCLICK;
1395     }
1396 
1397     returnCode(oldval);
1398 }
1399 
1400 /* This may be used by other routines to ask for the existence of mouse
1401    support */
1402 NCURSES_EXPORT(int)
1403 _nc_has_mouse(void)
1404 {
1405     return (SP->_mouse_type == M_NONE ? 0 : 1);
1406 }
1407 
1408 NCURSES_EXPORT(bool)
1409 wmouse_trafo(const WINDOW *win, int *pY, int *pX, bool to_screen)
1410 {
1411     bool result = FALSE;
1412 
1413     T((T_CALLED("wmouse_trafo(%p,%p,%p,%d)"), win, pY, pX, to_screen));
1414 
1415     if (win && pY && pX) {
1416 	int y = *pY;
1417 	int x = *pX;
1418 
1419 	if (to_screen) {
1420 	    y += win->_begy + win->_yoffset;
1421 	    x += win->_begx;
1422 	    if (wenclose(win, y, x))
1423 		result = TRUE;
1424 	} else {
1425 	    if (wenclose(win, y, x)) {
1426 		y -= (win->_begy + win->_yoffset);
1427 		x -= win->_begx;
1428 		result = TRUE;
1429 	    }
1430 	}
1431 	if (result) {
1432 	    *pX = x;
1433 	    *pY = y;
1434 	}
1435     }
1436     returnBool(result);
1437 }
1438