1 /****************************************************************************
2  * Copyright (c) 1998-2007,2008 Free Software Foundation, Inc.              *
3  *                                                                          *
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5  * copy of this software and associated documentation files (the            *
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11  *                                                                          *
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14  *                                                                          *
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22  *                                                                          *
23  * Except as contained in this notice, the name(s) of the above copyright   *
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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  * This module is intended to encapsulate ncurses's interface to pointing
37  * devices.
38  *
39  * The primary method used is xterm's internal mouse-tracking facility.
40  * Additional methods depend on the platform:
41  *	Alessandro Rubini's GPM server (Linux)
42  *	sysmouse (FreeBSD)
43  *	special-purpose mouse interface for OS/2 EMX.
44  *
45  * Notes for implementors of new mouse-interface methods:
46  *
47  * The code is logically split into a lower level that accepts event reports
48  * in a device-dependent format and an upper level that parses mouse gestures
49  * and filters events.  The mediating data structure is a circular queue of
50  * MEVENT structures.
51  *
52  * Functionally, the lower level's job is to pick up primitive events and
53  * put them on the circular queue.  This can happen in one of two ways:
54  * either (a) _nc_mouse_event() detects a series of incoming mouse reports
55  * and queues them, or (b) code in lib_getch.c detects the kmous prefix in
56  * the keyboard input stream and calls _nc_mouse_inline to queue up a series
57  * of adjacent mouse reports.
58  *
59  * In either case, _nc_mouse_parse() should be called after the series is
60  * accepted to parse the digested mouse reports (low-level MEVENTs) into
61  * a gesture (a high-level or composite MEVENT).
62  *
63  * Don't be too shy about adding new event types or modifiers, if you can find
64  * room for them in the 32-bit mask.  The API is written so that users get
65  * feedback on which theoretical event types they won't see when they call
66  * mousemask. There's one bit per button (the RESERVED_EVENT bit) not being
67  * used yet, and a couple of bits open at the high end.
68  */
69 
70 #ifdef __EMX__
71 #  include <io.h>
72 #  define  INCL_DOS
73 #  define  INCL_VIO
74 #  define  INCL_KBD
75 #  define  INCL_MOU
76 #  define  INCL_DOSPROCESS
77 #  include <os2.h>		/* Need to include before the others */
78 #endif
79 
80 #include <curses.priv.h>
81 
82 MODULE_ID("$Id: lib_mouse.c,v 1.102 2008/10/18 21:48:55 tom Exp $")
83 
84 #include <term.h>
85 #include <tic.h>
86 
87 #if USE_GPM_SUPPORT
88 #include <linux/keyboard.h>	/* defines KG_* macros */
89 
90 #ifdef HAVE_LIBDL
91 /* use dynamic loader to avoid linkage dependency */
92 #include <dlfcn.h>
93 
94 #ifdef RTLD_NOW
95 #define my_RTLD RTLD_NOW
96 #else
97 #ifdef RTLD_LAZY
98 #define my_RTLD RTLD_LAZY
99 #else
100 make an error
101 #endif
102 #endif				/* RTLD_NOW */
103 #endif				/* HAVE_LIBDL */
104 
105 #endif				/* USE_GPM_SUPPORT */
106 
107 #if USE_SYSMOUSE
108 #undef buttons			/* symbol conflict in consio.h */
109 #undef mouse_info		/* symbol conflict in consio.h */
110 #include <osreldate.h>
111 #if (__FreeBSD_version >= 400017)
112 #include <sys/consio.h>
113 #include <sys/fbio.h>
114 #else
115 #include <machine/console.h>
116 #endif
117 #endif				/* use_SYSMOUSE */
118 
119 #define MY_TRACE TRACE_ICALLS|TRACE_IEVENT
120 
121 #define	MASK_RELEASE(x)		NCURSES_MOUSE_MASK(x, 001)
122 #define	MASK_PRESS(x)		NCURSES_MOUSE_MASK(x, 002)
123 #define	MASK_CLICK(x)		NCURSES_MOUSE_MASK(x, 004)
124 #define	MASK_DOUBLE_CLICK(x)	NCURSES_MOUSE_MASK(x, 010)
125 #define	MASK_TRIPLE_CLICK(x)	NCURSES_MOUSE_MASK(x, 020)
126 #define	MASK_RESERVED_EVENT(x)	NCURSES_MOUSE_MASK(x, 040)
127 
128 #if NCURSES_MOUSE_VERSION == 1
129 #define BUTTON_CLICKED        (BUTTON1_CLICKED        | BUTTON2_CLICKED        | BUTTON3_CLICKED        | BUTTON4_CLICKED)
130 #define BUTTON_PRESSED        (BUTTON1_PRESSED        | BUTTON2_PRESSED        | BUTTON3_PRESSED        | BUTTON4_PRESSED)
131 #define BUTTON_RELEASED       (BUTTON1_RELEASED       | BUTTON2_RELEASED       | BUTTON3_RELEASED       | BUTTON4_RELEASED)
132 #define BUTTON_DOUBLE_CLICKED (BUTTON1_DOUBLE_CLICKED | BUTTON2_DOUBLE_CLICKED | BUTTON3_DOUBLE_CLICKED | BUTTON4_DOUBLE_CLICKED)
133 #define BUTTON_TRIPLE_CLICKED (BUTTON1_TRIPLE_CLICKED | BUTTON2_TRIPLE_CLICKED | BUTTON3_TRIPLE_CLICKED | BUTTON4_TRIPLE_CLICKED)
134 #define MAX_BUTTONS  4
135 #else
136 #define BUTTON_CLICKED        (BUTTON1_CLICKED        | BUTTON2_CLICKED        | BUTTON3_CLICKED        | BUTTON4_CLICKED        | BUTTON5_CLICKED)
137 #define BUTTON_PRESSED        (BUTTON1_PRESSED        | BUTTON2_PRESSED        | BUTTON3_PRESSED        | BUTTON4_PRESSED        | BUTTON5_PRESSED)
138 #define BUTTON_RELEASED       (BUTTON1_RELEASED       | BUTTON2_RELEASED       | BUTTON3_RELEASED       | BUTTON4_RELEASED       | BUTTON5_RELEASED)
139 #define BUTTON_DOUBLE_CLICKED (BUTTON1_DOUBLE_CLICKED | BUTTON2_DOUBLE_CLICKED | BUTTON3_DOUBLE_CLICKED | BUTTON4_DOUBLE_CLICKED | BUTTON5_DOUBLE_CLICKED)
140 #define BUTTON_TRIPLE_CLICKED (BUTTON1_TRIPLE_CLICKED | BUTTON2_TRIPLE_CLICKED | BUTTON3_TRIPLE_CLICKED | BUTTON4_TRIPLE_CLICKED | BUTTON5_TRIPLE_CLICKED)
141 #define MAX_BUTTONS  5
142 #endif
143 
144 #define INVALID_EVENT	-1
145 #define NORMAL_EVENT	0
146 
147 #if USE_GPM_SUPPORT
148 
149 #ifndef LIBGPM_SONAME
150 #define LIBGPM_SONAME "libgpm.so"
151 #endif
152 
153 #define GET_DLSYM(name) (my_##name = (TYPE_##name) dlsym(SP->_dlopen_gpm, #name))
154 
155 #endif				/* USE_GPM_SUPPORT */
156 
157 static bool _nc_mouse_parse(SCREEN *, int);
158 static void _nc_mouse_resume(SCREEN *);
159 static void _nc_mouse_wrap(SCREEN *);
160 
161 /* maintain a circular list of mouse events */
162 
163 #define FirstEV(sp)	((sp)->_mouse_events)
164 #define LastEV(sp)	((sp)->_mouse_events + EV_MAX - 1)
165 
166 #undef  NEXT
167 #define NEXT(ep)	((ep >= LastEV(sp)) \
168 			 ? FirstEV(sp) \
169 			 : ep + 1)
170 
171 #undef  PREV
172 #define PREV(ep)	((ep <= FirstEV(sp)) \
173 			 ? LastEV(sp) \
174 			 : ep - 1)
175 
176 #define IndexEV(sp, ep)	(ep - FirstEV(sp))
177 
178 #define RunParams(sp, eventp, runp) \
179 		(long) IndexEV(sp, runp), \
180 		(long) (IndexEV(sp, eventp) + (EV_MAX - 1)) % EV_MAX
181 
182 #ifdef TRACE
183 static void
184 _trace_slot(SCREEN *sp, const char *tag)
185 {
186     MEVENT *ep;
187 
188     _tracef(tag);
189 
190     for (ep = FirstEV(sp); ep <= LastEV(sp); ep++)
191 	_tracef("mouse event queue slot %ld = %s",
192 		(long) IndexEV(sp, ep),
193 		_nc_tracemouse(sp, ep));
194 }
195 #endif
196 
197 #if USE_EMX_MOUSE
198 
199 #  define TOP_ROW          0
200 #  define LEFT_COL         0
201 
202 #  define M_FD(sp) sp->_mouse_fd
203 
204 static void
205 write_event(SCREEN *sp, int down, int button, int x, int y)
206 {
207     char buf[6];
208     unsigned long ignore;
209 
210     strncpy(buf, key_mouse, 3);	/* should be "\033[M" */
211     buf[3] = ' ' + (button - 1) + (down ? 0 : 0x40);
212     buf[4] = ' ' + x - LEFT_COL + 1;
213     buf[5] = ' ' + y - TOP_ROW + 1;
214     DosWrite(sp->_emxmouse_wfd, buf, 6, &ignore);
215 }
216 
217 static void
218 mouse_server(unsigned long param)
219 {
220     SCREEN *sp = (SCREEN *) param;
221     unsigned short fWait = MOU_WAIT;
222     /* NOPTRRECT mourt = { 0,0,24,79 }; */
223     MOUEVENTINFO mouev;
224     HMOU hmou;
225     unsigned short mask = MOUSE_BN1_DOWN | MOUSE_BN2_DOWN | MOUSE_BN3_DOWN;
226     int nbuttons = 3;
227     int oldstate = 0;
228     char err[80];
229     unsigned long rc;
230 
231     /* open the handle for the mouse */
232     if (MouOpen(NULL, &hmou) == 0) {
233 	rc = MouSetEventMask(&mask, hmou);
234 	if (rc) {		/* retry with 2 buttons */
235 	    mask = MOUSE_BN1_DOWN | MOUSE_BN2_DOWN;
236 	    rc = MouSetEventMask(&mask, hmou);
237 	    nbuttons = 2;
238 	}
239 	if (rc == 0 && MouDrawPtr(hmou) == 0) {
240 	    for (;;) {
241 		/* sit and wait on the event queue */
242 		rc = MouReadEventQue(&mouev, &fWait, hmou);
243 		if (rc) {
244 		    sprintf(err, "Error reading mouse queue, rc=%lu.\r\n", rc);
245 		    break;
246 		}
247 		if (!sp->_emxmouse_activated)
248 		    goto finish;
249 
250 		/*
251 		 * OS/2 numbers a 3-button mouse inconsistently from other
252 		 * platforms:
253 		 *      1 = left
254 		 *      2 = right
255 		 *      3 = middle.
256 		 */
257 		if ((mouev.fs ^ oldstate) & MOUSE_BN1_DOWN)
258 		    write_event(sp, mouev.fs & MOUSE_BN1_DOWN,
259 				sp->_emxmouse_buttons[1], mouev.col, mouev.row);
260 		if ((mouev.fs ^ oldstate) & MOUSE_BN2_DOWN)
261 		    write_event(sp, mouev.fs & MOUSE_BN2_DOWN,
262 				sp->_emxmouse_buttons[3], mouev.col, mouev.row);
263 		if ((mouev.fs ^ oldstate) & MOUSE_BN3_DOWN)
264 		    write_event(sp, mouev.fs & MOUSE_BN3_DOWN,
265 				sp->_emxmouse_buttons[2], mouev.col, mouev.row);
266 
267 	      finish:
268 		oldstate = mouev.fs;
269 	    }
270 	} else
271 	    sprintf(err, "Error setting event mask, buttons=%d, rc=%lu.\r\n",
272 		    nbuttons, rc);
273 
274 	DosWrite(2, err, strlen(err), &rc);
275 	MouClose(hmou);
276     }
277     DosExit(EXIT_THREAD, 0L);
278 }
279 
280 #endif /* USE_EMX_MOUSE */
281 
282 #if USE_SYSMOUSE
283 static void
284 sysmouse_server(SCREEN *sp)
285 {
286     struct mouse_info the_mouse;
287     MEVENT *work;
288 
289     the_mouse.operation = MOUSE_GETINFO;
290     if (sp != 0
291 	&& sp->_mouse_fd >= 0
292 	&& sp->_sysmouse_tail < FIFO_SIZE
293 	&& ioctl(sp->_mouse_fd, CONS_MOUSECTL, &the_mouse) != -1) {
294 
295 	if (sp->_sysmouse_head > sp->_sysmouse_tail) {
296 	    sp->_sysmouse_tail = 0;
297 	    sp->_sysmouse_head = 0;
298 	}
299 	work = &(sp->_sysmouse_fifo[sp->_sysmouse_tail]);
300 	memset(work, 0, sizeof(*work));
301 	work->id = NORMAL_EVENT;	/* there's only one mouse... */
302 
303 	sp->_sysmouse_old_buttons = sp->_sysmouse_new_buttons;
304 	sp->_sysmouse_new_buttons = the_mouse.u.data.buttons & 0x7;
305 
306 	if (sp->_sysmouse_new_buttons) {
307 	    if (sp->_sysmouse_new_buttons & 1)
308 		work->bstate |= BUTTON1_PRESSED;
309 	    if (sp->_sysmouse_new_buttons & 2)
310 		work->bstate |= BUTTON2_PRESSED;
311 	    if (sp->_sysmouse_new_buttons & 4)
312 		work->bstate |= BUTTON3_PRESSED;
313 	} else {
314 	    if (sp->_sysmouse_old_buttons & 1)
315 		work->bstate |= BUTTON1_RELEASED;
316 	    if (sp->_sysmouse_old_buttons & 2)
317 		work->bstate |= BUTTON2_RELEASED;
318 	    if (sp->_sysmouse_old_buttons & 4)
319 		work->bstate |= BUTTON3_RELEASED;
320 	}
321 
322 	/* for cosmetic bug in syscons.c on FreeBSD 3.[34] */
323 	the_mouse.operation = MOUSE_HIDE;
324 	ioctl(sp->_mouse_fd, CONS_MOUSECTL, &the_mouse);
325 	the_mouse.operation = MOUSE_SHOW;
326 	ioctl(sp->_mouse_fd, CONS_MOUSECTL, &the_mouse);
327 
328 	/*
329 	 * We're only interested if the button is pressed or released.
330 	 * FIXME: implement continuous event-tracking.
331 	 */
332 	if (sp->_sysmouse_new_buttons != sp->_sysmouse_old_buttons) {
333 	    sp->_sysmouse_tail += 1;
334 	}
335 	work->x = the_mouse.u.data.x / sp->_sysmouse_char_width;
336 	work->y = the_mouse.u.data.y / sp->_sysmouse_char_height;
337     }
338 }
339 
340 static void
341 handle_sysmouse(int sig GCC_UNUSED)
342 {
343     sysmouse_server(SP);
344 }
345 #endif /* USE_SYSMOUSE */
346 
347 static void
348 init_xterm_mouse(SCREEN *sp)
349 {
350     sp->_mouse_type = M_XTERM;
351     sp->_mouse_xtermcap = tigetstr("XM");
352     if (!VALID_STRING(sp->_mouse_xtermcap))
353 	sp->_mouse_xtermcap = "\033[?1000%?%p1%{1}%=%th%el%;";
354 }
355 
356 static void
357 enable_xterm_mouse(SCREEN *sp, int enable)
358 {
359 #if USE_EMX_MOUSE
360     sp->_emxmouse_activated = enable;
361 #else
362     putp(TPARM_1(sp->_mouse_xtermcap, enable));
363 #endif
364     sp->_mouse_active = enable;
365 }
366 
367 #if USE_GPM_SUPPORT
368 static bool
369 allow_gpm_mouse(void)
370 {
371     bool result = FALSE;
372 
373     /* GPM does printf's without checking if stdout is a terminal */
374     if (isatty(fileno(stdout))) {
375 	char *list = getenv("NCURSES_GPM_TERMS");
376 	char *env = getenv("TERM");
377 	if (list != 0) {
378 	    if (env != 0) {
379 		result = _nc_name_match(list, env, "|:");
380 	    }
381 	} else {
382 	    /* GPM checks the beginning of the $TERM variable to decide if it
383 	     * should pass xterm events through.  There is no real advantage in
384 	     * allowing GPM to do this.  Recent versions relax that check, and
385 	     * pretend that GPM can work with any terminal having the kmous
386 	     * capability.  Perhaps that works for someone.  If so, they can
387 	     * set the environment variable (above).
388 	     */
389 	    if (env != 0 && strstr(env, "linux") != 0) {
390 		result = TRUE;
391 	    }
392 	}
393     }
394     return result;
395 }
396 
397 #ifdef HAVE_LIBDL
398 static void
399 unload_gpm_library(SCREEN *sp)
400 {
401     if (SP->_dlopen_gpm != 0) {
402 	T(("unload GPM library"));
403 	sp->_mouse_gpm_loaded = FALSE;
404 	sp->_mouse_fd = -1;
405 	dlclose(sp->_dlopen_gpm);
406 	sp->_dlopen_gpm = 0;
407     }
408 }
409 
410 static void
411 load_gpm_library(SCREEN *sp)
412 {
413     sp->_mouse_gpm_found = FALSE;
414     if ((sp->_dlopen_gpm = dlopen(LIBGPM_SONAME, my_RTLD)) != 0) {
415 	if (GET_DLSYM(gpm_fd) == 0 ||
416 	    GET_DLSYM(Gpm_Open) == 0 ||
417 	    GET_DLSYM(Gpm_Close) == 0 ||
418 	    GET_DLSYM(Gpm_GetEvent) == 0) {
419 	    T(("GPM initialization failed: %s", dlerror()));
420 	    unload_gpm_library(sp);
421 	} else {
422 	    sp->_mouse_gpm_found = TRUE;
423 	    sp->_mouse_gpm_loaded = TRUE;
424 	}
425     }
426 }
427 #endif
428 
429 static bool
430 enable_gpm_mouse(SCREEN *sp, bool enable)
431 {
432     bool result;
433 
434     T((T_CALLED("enable_gpm_mouse(%d)"), enable));
435 
436     if (enable && !sp->_mouse_active) {
437 #ifdef HAVE_LIBDL
438 	if (sp->_mouse_gpm_found && !sp->_mouse_gpm_loaded) {
439 	    load_gpm_library(sp);
440 	}
441 #endif
442 	if (sp->_mouse_gpm_loaded) {
443 	    /* GPM: initialize connection to gpm server */
444 	    sp->_mouse_gpm_connect.eventMask = GPM_DOWN | GPM_UP;
445 	    sp->_mouse_gpm_connect.defaultMask =
446 		(unsigned short) (~(sp->_mouse_gpm_connect.eventMask | GPM_HARD));
447 	    sp->_mouse_gpm_connect.minMod = 0;
448 	    sp->_mouse_gpm_connect.maxMod =
449 		(unsigned short) (~((1 << KG_SHIFT) |
450 				    (1 << KG_SHIFTL) |
451 				    (1 << KG_SHIFTR)));
452 	    /*
453 	     * Note: GPM hardcodes \E[?1001s and \E[?1000h during its open.
454 	     * The former is recognized by wscons (SunOS), and the latter by
455 	     * xterm.  Those will not show up in ncurses' traces.
456 	     */
457 	    result = (my_Gpm_Open(&sp->_mouse_gpm_connect, 0) >= 0);
458 	} else {
459 	    result = FALSE;
460 	}
461 	sp->_mouse_active = result;
462 	T(("GPM open %s", result ? "succeeded" : "failed"));
463     } else {
464 	if (!enable && sp->_mouse_active) {
465 	    /* GPM: close connection to gpm server */
466 	    my_Gpm_Close();
467 	    sp->_mouse_active = FALSE;
468 	    T(("GPM closed"));
469 	}
470 	result = enable;
471     }
472 #ifdef HAVE_LIBDL
473     if (!result) {
474 	unload_gpm_library(sp);
475     }
476 #endif
477     returnBool(result);
478 }
479 #endif /* USE_GPM_SUPPORT */
480 
481 #define xterm_kmous "\033[M"
482 
483 static void
484 initialize_mousetype(SCREEN *sp)
485 {
486     T((T_CALLED("initialize_mousetype()")));
487 
488     /* Try gpm first, because gpm may be configured to run in xterm */
489 #if USE_GPM_SUPPORT
490     if (allow_gpm_mouse()) {
491 	if (!sp->_mouse_gpm_loaded) {
492 #ifdef HAVE_LIBDL
493 	    load_gpm_library(sp);
494 #else /* !HAVE_LIBDL */
495 	    sp->_mouse_gpm_found = TRUE;
496 	    sp->_mouse_gpm_loaded = TRUE;
497 #endif
498 	}
499 
500 	/*
501 	 * The gpm_fd file-descriptor may be negative (xterm).  So we have to
502 	 * maintain our notion of whether the mouse connection is active
503 	 * without testing the file-descriptor.
504 	 */
505 	if (sp->_mouse_gpm_found && enable_gpm_mouse(sp, TRUE)) {
506 	    sp->_mouse_type = M_GPM;
507 	    sp->_mouse_fd = *(my_gpm_fd);
508 	    T(("GPM mouse_fd %d", sp->_mouse_fd));
509 	    returnVoid;
510 	}
511     }
512 #endif /* USE_GPM_SUPPORT */
513 
514     /* OS/2 VIO */
515 #if USE_EMX_MOUSE
516     if (!sp->_emxmouse_thread
517 	&& strstr(cur_term->type.term_names, "xterm") == 0
518 	&& key_mouse) {
519 	int handles[2];
520 
521 	if (pipe(handles) < 0) {
522 	    perror("mouse pipe error");
523 	    returnVoid;
524 	} else {
525 	    int rc;
526 
527 	    if (!sp->_emxmouse_buttons[0]) {
528 		char *s = getenv("MOUSE_BUTTONS_123");
529 
530 		sp->_emxmouse_buttons[0] = 1;
531 		if (s && strlen(s) >= 3) {
532 		    sp->_emxmouse_buttons[1] = s[0] - '0';
533 		    sp->_emxmouse_buttons[2] = s[1] - '0';
534 		    sp->_emxmouse_buttons[3] = s[2] - '0';
535 		} else {
536 		    sp->_emxmouse_buttons[1] = 1;
537 		    sp->_emxmouse_buttons[2] = 3;
538 		    sp->_emxmouse_buttons[3] = 2;
539 		}
540 	    }
541 	    sp->_emxmouse_wfd = handles[1];
542 	    M_FD(sp) = handles[0];
543 	    /* Needed? */
544 	    setmode(handles[0], O_BINARY);
545 	    setmode(handles[1], O_BINARY);
546 	    /* Do not use CRT functions, we may single-threaded. */
547 	    rc = DosCreateThread((unsigned long *) &sp->_emxmouse_thread,
548 				 mouse_server, (long) sp, 0, 8192);
549 	    if (rc) {
550 		printf("mouse thread error %d=%#x", rc, rc);
551 	    } else {
552 		sp->_mouse_type = M_XTERM;
553 	    }
554 	    returnVoid;
555 	}
556     }
557 #endif /* USE_EMX_MOUSE */
558 
559 #if USE_SYSMOUSE
560     {
561 	struct mouse_info the_mouse;
562 	char *the_device = 0;
563 
564 	if (isatty(sp->_ifd))
565 	    the_device = ttyname(sp->_ifd);
566 	if (the_device == 0)
567 	    the_device = "/dev/tty";
568 
569 	sp->_mouse_fd = open(the_device, O_RDWR);
570 
571 	if (sp->_mouse_fd >= 0) {
572 	    /*
573 	     * sysmouse does not have a usable user interface for obtaining
574 	     * mouse events.  The logical way to proceed (reading data on a
575 	     * stream) only works if one opens the device as root.  Even in
576 	     * that mode, careful examination shows we lose events
577 	     * occasionally.  The interface provided for user programs is to
578 	     * establish a signal handler.  really.
579 	     *
580 	     * Take over SIGUSR2 for this purpose since SIGUSR1 is more
581 	     * likely to be used by an application.  getch() will have to
582 	     * handle the misleading EINTR's.
583 	     */
584 	    signal(SIGUSR2, SIG_IGN);
585 	    the_mouse.operation = MOUSE_MODE;
586 	    the_mouse.u.mode.mode = 0;
587 	    the_mouse.u.mode.signal = SIGUSR2;
588 	    if (ioctl(sp->_mouse_fd, CONS_MOUSECTL, &the_mouse) != -1) {
589 		signal(SIGUSR2, handle_sysmouse);
590 		the_mouse.operation = MOUSE_SHOW;
591 		ioctl(sp->_mouse_fd, CONS_MOUSECTL, &the_mouse);
592 
593 #if defined(FBIO_MODEINFO) || defined(CONS_MODEINFO)	/* FreeBSD > 2.x */
594 		{
595 #ifndef FBIO_GETMODE		/* FreeBSD 3.x */
596 #define FBIO_GETMODE    CONS_GET
597 #define FBIO_MODEINFO   CONS_MODEINFO
598 #endif /* FBIO_GETMODE */
599 		    video_info_t the_video;
600 
601 		    if (ioctl(sp->_mouse_fd,
602 			      FBIO_GETMODE,
603 			      &the_video.vi_mode) != -1
604 			&& ioctl(sp->_mouse_fd,
605 				 FBIO_MODEINFO,
606 				 &the_video) != -1) {
607 			sp->_sysmouse_char_width = the_video.vi_cwidth;
608 			sp->_sysmouse_char_height = the_video.vi_cheight;
609 		    }
610 		}
611 #endif /* defined(FBIO_MODEINFO) || defined(CONS_MODEINFO) */
612 
613 		if (sp->_sysmouse_char_width <= 0)
614 		    sp->_sysmouse_char_width = 8;
615 		if (sp->_sysmouse_char_height <= 0)
616 		    sp->_sysmouse_char_height = 16;
617 		sp->_mouse_type = M_SYSMOUSE;
618 		returnVoid;
619 	    }
620 	}
621     }
622 #endif /* USE_SYSMOUSE */
623 
624     /* we know how to recognize mouse events under "xterm" */
625     if (key_mouse != 0) {
626 	if (!strcmp(key_mouse, xterm_kmous)
627 	    || strstr(cur_term->type.term_names, "xterm") != 0) {
628 	    init_xterm_mouse(sp);
629 	}
630     } else if (strstr(cur_term->type.term_names, "xterm") != 0) {
631 	if (_nc_add_to_try(&(sp->_keytry), xterm_kmous, KEY_MOUSE) == OK)
632 	    init_xterm_mouse(sp);
633     }
634     returnVoid;
635 }
636 
637 static bool
638 _nc_mouse_init(SCREEN *sp)
639 /* initialize the mouse */
640 {
641     bool result = FALSE;
642     int i;
643 
644     if (sp != 0) {
645 	if (!sp->_mouse_initialized) {
646 	    sp->_mouse_initialized = TRUE;
647 
648 	    TR(MY_TRACE, ("_nc_mouse_init() called"));
649 
650 	    sp->_mouse_eventp = FirstEV(sp);
651 	    for (i = 0; i < EV_MAX; i++)
652 		sp->_mouse_events[i].id = INVALID_EVENT;
653 
654 	    initialize_mousetype(sp);
655 
656 	    T(("_nc_mouse_init() set mousetype to %d", sp->_mouse_type));
657 	}
658 	result = sp->_mouse_initialized;
659     }
660     return result;
661 }
662 
663 /*
664  * Query to see if there is a pending mouse event.  This is called from
665  * fifo_push() in lib_getch.c
666  */
667 static bool
668 _nc_mouse_event(SCREEN *sp GCC_UNUSED)
669 {
670     MEVENT *eventp = sp->_mouse_eventp;
671     bool result = FALSE;
672 
673     (void) eventp;
674 
675     switch (sp->_mouse_type) {
676     case M_XTERM:
677 	/* xterm: never have to query, mouse events are in the keyboard stream */
678 #if USE_EMX_MOUSE
679 	{
680 	    char kbuf[3];
681 
682 	    int i, res = read(M_FD(sp), &kbuf, 3);	/* Eat the prefix */
683 	    if (res != 3)
684 		printf("Got %d chars instead of 3 for prefix.\n", res);
685 	    for (i = 0; i < res; i++) {
686 		if (kbuf[i] != key_mouse[i])
687 		    printf("Got char %d instead of %d for prefix.\n",
688 			   (int) kbuf[i], (int) key_mouse[i]);
689 	    }
690 	    result = TRUE;
691 	}
692 #endif /* USE_EMX_MOUSE */
693 	break;
694 
695 #if USE_GPM_SUPPORT
696     case M_GPM:
697 	{
698 	    /* query server for event, return TRUE if we find one */
699 	    Gpm_Event ev;
700 
701 	    if (my_Gpm_GetEvent(&ev) == 1) {
702 		/* there's only one mouse... */
703 		eventp->id = NORMAL_EVENT;
704 
705 		eventp->bstate = 0;
706 		switch (ev.type & 0x0f) {
707 		case (GPM_DOWN):
708 		    if (ev.buttons & GPM_B_LEFT)
709 			eventp->bstate |= BUTTON1_PRESSED;
710 		    if (ev.buttons & GPM_B_MIDDLE)
711 			eventp->bstate |= BUTTON2_PRESSED;
712 		    if (ev.buttons & GPM_B_RIGHT)
713 			eventp->bstate |= BUTTON3_PRESSED;
714 		    break;
715 		case (GPM_UP):
716 		    if (ev.buttons & GPM_B_LEFT)
717 			eventp->bstate |= BUTTON1_RELEASED;
718 		    if (ev.buttons & GPM_B_MIDDLE)
719 			eventp->bstate |= BUTTON2_RELEASED;
720 		    if (ev.buttons & GPM_B_RIGHT)
721 			eventp->bstate |= BUTTON3_RELEASED;
722 		    break;
723 		default:
724 		    break;
725 		}
726 
727 		eventp->x = ev.x - 1;
728 		eventp->y = ev.y - 1;
729 		eventp->z = 0;
730 
731 		/* bump the next-free pointer into the circular list */
732 		sp->_mouse_eventp = eventp = NEXT(eventp);
733 		result = TRUE;
734 	    }
735 	}
736 	break;
737 #endif
738 
739 #if USE_SYSMOUSE
740     case M_SYSMOUSE:
741 	if (sp->_sysmouse_head < sp->_sysmouse_tail) {
742 	    *eventp = sp->_sysmouse_fifo[sp->_sysmouse_head];
743 
744 	    /*
745 	     * Point the fifo-head to the next possible location.  If there
746 	     * are none, reset the indices.  This may be interrupted by the
747 	     * signal handler, doing essentially the same reset.
748 	     */
749 	    sp->_sysmouse_head += 1;
750 	    if (sp->_sysmouse_head == sp->_sysmouse_tail) {
751 		sp->_sysmouse_tail = 0;
752 		sp->_sysmouse_head = 0;
753 	    }
754 
755 	    /* bump the next-free pointer into the circular list */
756 	    sp->_mouse_eventp = eventp = NEXT(eventp);
757 	    result = TRUE;
758 	}
759 	break;
760 #endif /* USE_SYSMOUSE */
761 
762     case M_NONE:
763 	break;
764     }
765 
766     return result;		/* true if we found an event */
767 }
768 
769 static bool
770 _nc_mouse_inline(SCREEN *sp)
771 /* mouse report received in the keyboard stream -- parse its info */
772 {
773     int b;
774     bool result = FALSE;
775     MEVENT *eventp = sp->_mouse_eventp;
776 
777     TR(MY_TRACE, ("_nc_mouse_inline() called"));
778 
779     if (sp->_mouse_type == M_XTERM) {
780 	unsigned char kbuf[4];
781 	mmask_t prev;
782 	size_t grabbed;
783 	int res;
784 
785 	/* This code requires that your xterm entry contain the kmous
786 	 * capability and that it be set to the \E[M documented in the
787 	 * Xterm Control Sequences reference.  This is how we
788 	 * arrange for mouse events to be reported via a KEY_MOUSE
789 	 * return value from wgetch().  After this value is received,
790 	 * _nc_mouse_inline() gets called and is immediately
791 	 * responsible for parsing the mouse status information
792 	 * following the prefix.
793 	 *
794 	 * The following quotes from the ctrlseqs.ms document in the
795 	 * X distribution, describing the X mouse tracking feature:
796 	 *
797 	 * Parameters for all mouse tracking escape sequences
798 	 * generated by xterm encode numeric parameters in a single
799 	 * character as value+040.  For example, !  is 1.
800 	 *
801 	 * On button press or release, xterm sends ESC [ M CbCxCy.
802 	 * The low two bits of Cb encode button information: 0=MB1
803 	 * pressed, 1=MB2 pressed, 2=MB3 pressed, 3=release.  The
804 	 * upper bits encode what modifiers were down when the
805 	 * button was pressed and are added together.  4=Shift,
806 	 * 8=Meta, 16=Control.  Cx and Cy are the x and y coordinates
807 	 * of the mouse event.  The upper left corner is (1,1).
808 	 *
809 	 * (End quote)  By the time we get here, we've eaten the
810 	 * key prefix.  FYI, the loop below is necessary because
811 	 * mouse click info isn't guaranteed to present as a
812 	 * single clist item.
813 	 *
814 	 * Wheel mice may return buttons 4 and 5 when the wheel is turned.
815 	 * We encode those as button presses.
816 	 */
817 	for (grabbed = 0; grabbed < 3; grabbed += (size_t) res) {
818 
819 	    /* For VIO mouse we add extra bit 64 to disambiguate button-up. */
820 #if USE_EMX_MOUSE
821 	    res = read(M_FD(sp) >= 0 ? M_FD(sp) : sp->_ifd, &kbuf, 3);
822 #else
823 	    res = read(sp->_ifd, kbuf + grabbed, 3 - grabbed);
824 #endif
825 	    if (res == -1)
826 		break;
827 	}
828 	kbuf[3] = '\0';
829 
830 	TR(TRACE_IEVENT,
831 	   ("_nc_mouse_inline sees the following xterm data: '%s'", kbuf));
832 
833 	/* there's only one mouse... */
834 	eventp->id = NORMAL_EVENT;
835 
836 	/* processing code goes here */
837 	eventp->bstate = 0;
838 	prev = PREV(eventp)->bstate;
839 
840 #if USE_EMX_MOUSE
841 #define PRESS_POSITION(n) \
842 	eventp->bstate = MASK_PRESS(n); \
843 	if (kbuf[0] & 0x40) \
844 	    eventp->bstate = MASK_RELEASE(n)
845 #else
846 #define PRESS_POSITION(n) \
847 	eventp->bstate = (mmask_t) (prev & MASK_PRESS(n) \
848 				    ? REPORT_MOUSE_POSITION \
849 				    : MASK_PRESS(n))
850 #endif
851 
852 	switch (kbuf[0] & 0x3) {
853 	case 0x0:
854 	    if (kbuf[0] & 64)
855 		eventp->bstate = MASK_PRESS(4);
856 	    else
857 		PRESS_POSITION(1);
858 	    break;
859 
860 	case 0x1:
861 #if NCURSES_MOUSE_VERSION == 2
862 	    if (kbuf[0] & 64)
863 		eventp->bstate = MASK_PRESS(5);
864 	    else
865 #endif
866 		PRESS_POSITION(2);
867 	    break;
868 
869 	case 0x2:
870 	    PRESS_POSITION(3);
871 	    break;
872 
873 	case 0x3:
874 	    /*
875 	     * Release events aren't reported for individual buttons, just for
876 	     * the button set as a whole.  However, because there are normally
877 	     * no mouse events under xterm that intervene between press and
878 	     * release, we can infer the button actually released by looking at
879 	     * the previous event.
880 	     */
881 	    if (prev & (BUTTON_PRESSED | BUTTON_RELEASED)) {
882 		eventp->bstate = BUTTON_RELEASED;
883 		for (b = 1; b <= MAX_BUTTONS; ++b) {
884 		    if (!(prev & MASK_PRESS(b)))
885 			eventp->bstate &= ~MASK_RELEASE(b);
886 		}
887 	    } else {
888 		/*
889 		 * XFree86 xterm will return a stream of release-events to
890 		 * let the application know where the mouse is going, if the
891 		 * private mode 1002 or 1003 is enabled.
892 		 */
893 		eventp->bstate = REPORT_MOUSE_POSITION;
894 	    }
895 	    break;
896 	}
897 	result = (eventp->bstate & REPORT_MOUSE_POSITION) ? TRUE : FALSE;
898 
899 	if (kbuf[0] & 4) {
900 	    eventp->bstate |= BUTTON_SHIFT;
901 	}
902 	if (kbuf[0] & 8) {
903 	    eventp->bstate |= BUTTON_ALT;
904 	}
905 	if (kbuf[0] & 16) {
906 	    eventp->bstate |= BUTTON_CTRL;
907 	}
908 
909 	eventp->x = (kbuf[1] - ' ') - 1;
910 	eventp->y = (kbuf[2] - ' ') - 1;
911 	TR(MY_TRACE,
912 	   ("_nc_mouse_inline: primitive mouse-event %s has slot %ld",
913 	    _nc_tracemouse(sp, eventp),
914 	    (long) IndexEV(sp, eventp)));
915 
916 	/* bump the next-free pointer into the circular list */
917 	sp->_mouse_eventp = NEXT(eventp);
918 #if 0				/* this return would be needed for QNX's mods to lib_getch.c */
919 	return (TRUE);
920 #endif
921     }
922 
923     return (result);
924 }
925 
926 static void
927 mouse_activate(SCREEN *sp, bool on)
928 {
929     if (!on && !sp->_mouse_initialized)
930 	return;
931 
932     if (!_nc_mouse_init(sp))
933 	return;
934 
935     if (on) {
936 
937 	switch (sp->_mouse_type) {
938 	case M_XTERM:
939 #if NCURSES_EXT_FUNCS
940 	    keyok(KEY_MOUSE, on);
941 #endif
942 	    TPUTS_TRACE("xterm mouse initialization");
943 	    enable_xterm_mouse(sp, 1);
944 	    break;
945 #if USE_GPM_SUPPORT
946 	case M_GPM:
947 	    if (enable_gpm_mouse(sp, TRUE)) {
948 		sp->_mouse_fd = *(my_gpm_fd);
949 		T(("GPM mouse_fd %d", sp->_mouse_fd));
950 	    }
951 	    break;
952 #endif
953 #if USE_SYSMOUSE
954 	case M_SYSMOUSE:
955 	    signal(SIGUSR2, handle_sysmouse);
956 	    sp->_mouse_active = TRUE;
957 	    break;
958 #endif
959 	case M_NONE:
960 	    return;
961 	}
962 	/* Make runtime binding to cut down on object size of applications that
963 	 * do not use the mouse (e.g., 'clear').
964 	 */
965 	sp->_mouse_event = _nc_mouse_event;
966 	sp->_mouse_inline = _nc_mouse_inline;
967 	sp->_mouse_parse = _nc_mouse_parse;
968 	sp->_mouse_resume = _nc_mouse_resume;
969 	sp->_mouse_wrap = _nc_mouse_wrap;
970     } else {
971 
972 	switch (sp->_mouse_type) {
973 	case M_XTERM:
974 	    TPUTS_TRACE("xterm mouse deinitialization");
975 	    enable_xterm_mouse(sp, 0);
976 	    break;
977 #if USE_GPM_SUPPORT
978 	case M_GPM:
979 	    enable_gpm_mouse(sp, FALSE);
980 	    break;
981 #endif
982 #if USE_SYSMOUSE
983 	case M_SYSMOUSE:
984 	    signal(SIGUSR2, SIG_IGN);
985 	    sp->_mouse_active = FALSE;
986 	    break;
987 #endif
988 	case M_NONE:
989 	    return;
990 	}
991     }
992     _nc_flush();
993 }
994 
995 /**************************************************************************
996  *
997  * Device-independent code
998  *
999  **************************************************************************/
1000 
1001 static bool
1002 _nc_mouse_parse(SCREEN *sp, int runcount)
1003 /* parse a run of atomic mouse events into a gesture */
1004 {
1005     MEVENT *eventp = sp->_mouse_eventp;
1006     MEVENT *ep, *runp, *next, *prev = PREV(eventp);
1007     int n;
1008     int b;
1009     bool merge;
1010 
1011     TR(MY_TRACE, ("_nc_mouse_parse(%d) called", runcount));
1012 
1013     /*
1014      * When we enter this routine, the event list next-free pointer
1015      * points just past a run of mouse events that we know were separated
1016      * in time by less than the critical click interval. The job of this
1017      * routine is to collapse this run into a single higher-level event
1018      * or gesture.
1019      *
1020      * We accomplish this in two passes.  The first pass merges press/release
1021      * pairs into click events.  The second merges runs of click events into
1022      * double or triple-click events.
1023      *
1024      * It's possible that the run may not resolve to a single event (for
1025      * example, if the user quadruple-clicks).  If so, leading events
1026      * in the run are ignored.
1027      *
1028      * Note that this routine is independent of the format of the specific
1029      * format of the pointing-device's reports.  We can use it to parse
1030      * gestures on anything that reports press/release events on a per-
1031      * button basis, as long as the device-dependent mouse code puts stuff
1032      * on the queue in MEVENT format.
1033      */
1034     if (runcount == 1) {
1035 	TR(MY_TRACE,
1036 	   ("_nc_mouse_parse: returning simple mouse event %s at slot %ld",
1037 	    _nc_tracemouse(sp, prev),
1038 	    (long) IndexEV(sp, prev)));
1039 	return (prev->id >= NORMAL_EVENT)
1040 	    ? ((prev->bstate & sp->_mouse_mask) ? TRUE : FALSE)
1041 	    : FALSE;
1042     }
1043 
1044     /* find the start of the run */
1045     runp = eventp;
1046     for (n = runcount; n > 0; n--) {
1047 	runp = PREV(runp);
1048     }
1049 
1050 #ifdef TRACE
1051     if (USE_TRACEF(TRACE_IEVENT)) {
1052 	_trace_slot(sp, "before mouse press/release merge:");
1053 	_tracef("_nc_mouse_parse: run starts at %ld, ends at %ld, count %d",
1054 		RunParams(sp, eventp, runp),
1055 		runcount);
1056 	_nc_unlock_global(tracef);
1057     }
1058 #endif /* TRACE */
1059 
1060     /* first pass; merge press/release pairs */
1061     do {
1062 	merge = FALSE;
1063 	for (ep = runp; (next = NEXT(ep)) != eventp; ep = next) {
1064 
1065 #define MASK_CHANGED(x) (!(ep->bstate & MASK_PRESS(x)) \
1066 		      == !(next->bstate & MASK_RELEASE(x)))
1067 
1068 	    if (ep->x == next->x && ep->y == next->y
1069 		&& (ep->bstate & BUTTON_PRESSED)
1070 		&& MASK_CHANGED(1)
1071 		&& MASK_CHANGED(2)
1072 		&& MASK_CHANGED(3)
1073 		&& MASK_CHANGED(4)
1074 #if NCURSES_MOUSE_VERSION == 2
1075 		&& MASK_CHANGED(5)
1076 #endif
1077 		) {
1078 		for (b = 1; b <= MAX_BUTTONS; ++b) {
1079 		    if ((sp->_mouse_mask & MASK_CLICK(b))
1080 			&& (ep->bstate & MASK_PRESS(b))) {
1081 			ep->bstate &= ~MASK_PRESS(b);
1082 			ep->bstate |= MASK_CLICK(b);
1083 			merge = TRUE;
1084 		    }
1085 		}
1086 		if (merge)
1087 		    next->id = INVALID_EVENT;
1088 	    }
1089 	}
1090     } while
1091 	(merge);
1092 
1093 #ifdef TRACE
1094     if (USE_TRACEF(TRACE_IEVENT)) {
1095 	_trace_slot(sp, "before mouse click merge:");
1096 	_tracef("_nc_mouse_parse: run starts at %ld, ends at %ld, count %d",
1097 		RunParams(sp, eventp, runp),
1098 		runcount);
1099 	_nc_unlock_global(tracef);
1100     }
1101 #endif /* TRACE */
1102 
1103     /*
1104      * Second pass; merge click runs.  At this point, click events are
1105      * each followed by one invalid event. We merge click events
1106      * forward in the queue.
1107      *
1108      * NOTE: There is a problem with this design!  If the application
1109      * allows enough click events to pile up in the circular queue so
1110      * they wrap around, it will cheerfully merge the newest forward
1111      * into the oldest, creating a bogus doubleclick and confusing
1112      * the queue-traversal logic rather badly.  Generally this won't
1113      * happen, because calling getmouse() marks old events invalid and
1114      * ineligible for merges.  The true solution to this problem would
1115      * be to timestamp each MEVENT and perform the obvious sanity check,
1116      * but the timer element would have to have sub-second resolution,
1117      * which would get us into portability trouble.
1118      */
1119     do {
1120 	MEVENT *follower;
1121 
1122 	merge = FALSE;
1123 	for (ep = runp; (next = NEXT(ep)) != eventp; ep = next)
1124 	    if (ep->id != INVALID_EVENT) {
1125 		if (next->id != INVALID_EVENT)
1126 		    continue;
1127 		follower = NEXT(next);
1128 		if (follower->id == INVALID_EVENT)
1129 		    continue;
1130 
1131 		/* merge click events forward */
1132 		if ((ep->bstate & BUTTON_CLICKED)
1133 		    && (follower->bstate & BUTTON_CLICKED)) {
1134 		    for (b = 1; b <= MAX_BUTTONS; ++b) {
1135 			if ((sp->_mouse_mask & MASK_DOUBLE_CLICK(b))
1136 			    && (follower->bstate & MASK_CLICK(b))) {
1137 			    follower->bstate &= ~MASK_CLICK(b);
1138 			    follower->bstate |= MASK_DOUBLE_CLICK(b);
1139 			    merge = TRUE;
1140 			}
1141 		    }
1142 		    if (merge)
1143 			ep->id = INVALID_EVENT;
1144 		}
1145 
1146 		/* merge double-click events forward */
1147 		if ((ep->bstate & BUTTON_DOUBLE_CLICKED)
1148 		    && (follower->bstate & BUTTON_CLICKED)) {
1149 		    for (b = 1; b <= MAX_BUTTONS; ++b) {
1150 			if ((sp->_mouse_mask & MASK_TRIPLE_CLICK(b))
1151 			    && (follower->bstate & MASK_CLICK(b))) {
1152 			    follower->bstate &= ~MASK_CLICK(b);
1153 			    follower->bstate |= MASK_TRIPLE_CLICK(b);
1154 			    merge = TRUE;
1155 			}
1156 		    }
1157 		    if (merge)
1158 			ep->id = INVALID_EVENT;
1159 		}
1160 	    }
1161     } while
1162 	(merge);
1163 
1164 #ifdef TRACE
1165     if (USE_TRACEF(TRACE_IEVENT)) {
1166 	_trace_slot(sp, "before mouse event queue compaction:");
1167 	_tracef("_nc_mouse_parse: run starts at %ld, ends at %ld, count %d",
1168 		RunParams(sp, eventp, runp),
1169 		runcount);
1170 	_nc_unlock_global(tracef);
1171     }
1172 #endif /* TRACE */
1173 
1174     /*
1175      * Now try to throw away trailing events flagged invalid, or that
1176      * don't match the current event mask.
1177      */
1178     for (; runcount; prev = PREV(eventp), runcount--)
1179 	if (prev->id == INVALID_EVENT || !(prev->bstate & sp->_mouse_mask)) {
1180 	    sp->_mouse_eventp = eventp = prev;
1181 	}
1182 #ifdef TRACE
1183     if (USE_TRACEF(TRACE_IEVENT)) {
1184 	_trace_slot(sp, "after mouse event queue compaction:");
1185 	_tracef("_nc_mouse_parse: run starts at %ld, ends at %ld, count %d",
1186 		RunParams(sp, eventp, runp),
1187 		runcount);
1188 	_nc_unlock_global(tracef);
1189     }
1190     for (ep = runp; ep != eventp; ep = NEXT(ep))
1191 	if (ep->id != INVALID_EVENT)
1192 	    TR(MY_TRACE,
1193 	       ("_nc_mouse_parse: returning composite mouse event %s at slot %ld",
1194 		_nc_tracemouse(sp, ep),
1195 		(long) IndexEV(sp, ep)));
1196 #endif /* TRACE */
1197 
1198     /* after all this, do we have a valid event? */
1199     return (PREV(eventp)->id != INVALID_EVENT);
1200 }
1201 
1202 static void
1203 _nc_mouse_wrap(SCREEN *sp)
1204 /* release mouse -- called by endwin() before shellout/exit */
1205 {
1206     TR(MY_TRACE, ("_nc_mouse_wrap() called"));
1207 
1208     switch (sp->_mouse_type) {
1209     case M_XTERM:
1210 	if (sp->_mouse_mask)
1211 	    mouse_activate(sp, FALSE);
1212 	break;
1213 #if USE_GPM_SUPPORT
1214 	/* GPM: pass all mouse events to next client */
1215     case M_GPM:
1216 	if (sp->_mouse_mask)
1217 	    mouse_activate(sp, FALSE);
1218 	break;
1219 #endif
1220 #if USE_SYSMOUSE
1221     case M_SYSMOUSE:
1222 	mouse_activate(sp, FALSE);
1223 	break;
1224 #endif
1225     case M_NONE:
1226 	break;
1227     }
1228 }
1229 
1230 static void
1231 _nc_mouse_resume(SCREEN *sp)
1232 /* re-connect to mouse -- called by doupdate() after shellout */
1233 {
1234     TR(MY_TRACE, ("_nc_mouse_resume() called"));
1235 
1236     switch (sp->_mouse_type) {
1237     case M_XTERM:
1238 	/* xterm: re-enable reporting */
1239 	if (sp->_mouse_mask)
1240 	    mouse_activate(sp, TRUE);
1241 	break;
1242 
1243 #if USE_GPM_SUPPORT
1244     case M_GPM:
1245 	/* GPM: reclaim our event set */
1246 	if (sp->_mouse_mask)
1247 	    mouse_activate(sp, TRUE);
1248 	break;
1249 #endif
1250 
1251 #if USE_SYSMOUSE
1252     case M_SYSMOUSE:
1253 	mouse_activate(sp, TRUE);
1254 	break;
1255 #endif
1256     case M_NONE:
1257 	break;
1258     }
1259 }
1260 
1261 /**************************************************************************
1262  *
1263  * Mouse interface entry points for the API
1264  *
1265  **************************************************************************/
1266 
1267 static int
1268 _nc_getmouse(SCREEN *sp, MEVENT * aevent)
1269 {
1270     T((T_CALLED("getmouse(%p)"), aevent));
1271 
1272     if ((aevent != 0) && (sp != 0) && (sp->_mouse_type != M_NONE)) {
1273 	MEVENT *eventp = sp->_mouse_eventp;
1274 	/* compute the current-event pointer */
1275 	MEVENT *prev = PREV(eventp);
1276 
1277 	/* copy the event we find there */
1278 	*aevent = *prev;
1279 
1280 	TR(TRACE_IEVENT, ("getmouse: returning event %s from slot %ld",
1281 			  _nc_tracemouse(sp, prev),
1282 			  (long) IndexEV(sp, prev)));
1283 
1284 	prev->id = INVALID_EVENT;	/* so the queue slot becomes free */
1285 	returnCode(OK);
1286     }
1287     returnCode(ERR);
1288 }
1289 
1290 /* grab a copy of the current mouse event */
1291 NCURSES_EXPORT(int)
1292 getmouse(MEVENT * aevent)
1293 {
1294     return _nc_getmouse(SP, aevent);
1295 }
1296 
1297 static int
1298 _nc_ungetmouse(SCREEN *sp, MEVENT * aevent)
1299 {
1300     int result = ERR;
1301 
1302     T((T_CALLED("ungetmouse(%p)"), aevent));
1303 
1304     if (aevent != 0 && sp != 0) {
1305 	MEVENT *eventp = sp->_mouse_eventp;
1306 
1307 	/* stick the given event in the next-free slot */
1308 	*eventp = *aevent;
1309 
1310 	/* bump the next-free pointer into the circular list */
1311 	sp->_mouse_eventp = NEXT(eventp);
1312 
1313 	/* push back the notification event on the keyboard queue */
1314 	result = _nc_ungetch(sp, KEY_MOUSE);
1315     }
1316     returnCode(result);
1317 }
1318 
1319 /* enqueue a synthesized mouse event to be seen by the next wgetch() */
1320 NCURSES_EXPORT(int)
1321 ungetmouse(MEVENT * aevent)
1322 {
1323     return _nc_ungetmouse(SP, aevent);
1324 }
1325 
1326 NCURSES_EXPORT(mmask_t)
1327 mousemask(mmask_t newmask, mmask_t * oldmask)
1328 /* set the mouse event mask */
1329 {
1330     mmask_t result = 0;
1331 
1332     T((T_CALLED("mousemask(%#lx,%p)"), (unsigned long) newmask, oldmask));
1333 
1334     if (SP != 0) {
1335 	if (oldmask)
1336 	    *oldmask = SP->_mouse_mask;
1337 
1338 	if (newmask || SP->_mouse_initialized) {
1339 	    _nc_mouse_init(SP);
1340 	    if (SP->_mouse_type != M_NONE) {
1341 		result = newmask &
1342 		    (REPORT_MOUSE_POSITION
1343 		     | BUTTON_ALT
1344 		     | BUTTON_CTRL
1345 		     | BUTTON_SHIFT
1346 		     | BUTTON_PRESSED
1347 		     | BUTTON_RELEASED
1348 		     | BUTTON_CLICKED
1349 		     | BUTTON_DOUBLE_CLICKED
1350 		     | BUTTON_TRIPLE_CLICKED);
1351 
1352 		mouse_activate(SP, (bool) (result != 0));
1353 
1354 		SP->_mouse_mask = result;
1355 	    }
1356 	}
1357     }
1358     returnBits(result);
1359 }
1360 
1361 NCURSES_EXPORT(bool)
1362 wenclose(const WINDOW *win, int y, int x)
1363 /* check to see if given window encloses given screen location */
1364 {
1365     bool result = FALSE;
1366 
1367     T((T_CALLED("wenclose(%p,%d,%d)"), win, y, x));
1368 
1369     if (win != 0) {
1370 	y -= win->_yoffset;
1371 	result = ((win->_begy <= y &&
1372 		   win->_begx <= x &&
1373 		   (win->_begx + win->_maxx) >= x &&
1374 		   (win->_begy + win->_maxy) >= y) ? TRUE : FALSE);
1375     }
1376     returnBool(result);
1377 }
1378 
1379 NCURSES_EXPORT(int)
1380 mouseinterval(int maxclick)
1381 /* set the maximum mouse interval within which to recognize a click */
1382 {
1383     int oldval;
1384 
1385     T((T_CALLED("mouseinterval(%d)"), maxclick));
1386 
1387     if (SP != 0) {
1388 	oldval = SP->_maxclick;
1389 	if (maxclick >= 0)
1390 	    SP->_maxclick = maxclick;
1391     } else {
1392 	oldval = DEFAULT_MAXCLICK;
1393     }
1394 
1395     returnCode(oldval);
1396 }
1397 
1398 /* This may be used by other routines to ask for the existence of mouse
1399    support */
1400 NCURSES_EXPORT(int)
1401 _nc_has_mouse(void)
1402 {
1403     return (SP->_mouse_type == M_NONE ? 0 : 1);
1404 }
1405 
1406 NCURSES_EXPORT(bool)
1407 wmouse_trafo(const WINDOW *win, int *pY, int *pX, bool to_screen)
1408 {
1409     bool result = FALSE;
1410 
1411     T((T_CALLED("wmouse_trafo(%p,%p,%p,%d)"), win, pY, pX, to_screen));
1412 
1413     if (win && pY && pX) {
1414 	int y = *pY;
1415 	int x = *pX;
1416 
1417 	if (to_screen) {
1418 	    y += win->_begy + win->_yoffset;
1419 	    x += win->_begx;
1420 	    if (wenclose(win, y, x))
1421 		result = TRUE;
1422 	} else {
1423 	    if (wenclose(win, y, x)) {
1424 		y -= (win->_begy + win->_yoffset);
1425 		x -= win->_begx;
1426 		result = TRUE;
1427 	    }
1428 	}
1429 	if (result) {
1430 	    *pX = x;
1431 	    *pY = y;
1432 	}
1433     }
1434     returnBool(result);
1435 }
1436