aboutsummaryrefslogtreecommitdiff
path: root/nx-X11/programs/Xserver/hw/sunLynx/sunLyMouse.c
blob: 00df3db7cd1cee734bade58fe8a9c1dd43f0a35b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
/* $Xorg: sunLyMouse.c,v 1.3 2000/08/17 19:48:37 cpqbld Exp $ */
/*
 * This is sunMouse.c modified for LynxOS
 * Copyright 1996 by Thomas Mueller
 *
 * Permission to use, copy, modify, distribute, and sell this software and its
 * documentation for any purpose is hereby granted without fee, provided that
 * the above copyright notice appear in all copies and that both that
 * copyright notice and this permission notice appear in supporting
 * documentation, and that the name of Thomas Mueller not be used in
 * advertising or publicity pertaining to distribution of the software without
 * specific, written prior permission.  Thomas Mueller makes no representations
 * about the suitability of this software for any purpose.  It is provided
 * "as is" without express or implied warranty.
 *
 * THOMAS MUELLER DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
 * EVENT SHALL THOMAS MUELLER BE LIABLE FOR ANY SPECIAL, INDIRECT OR
 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 * PERFORMANCE OF THIS SOFTWARE.
 *
 */
/* $XFree86: xc/programs/Xserver/hw/sunLynx/sunLyMouse.c,v 3.3 2001/01/17 22:36:53 dawes Exp $ */

/*-
 * Copyright 1987 by the Regents of the University of California
 *
 * Permission to use, copy, modify, and distribute this
 * software and its documentation for any purpose and without
 * fee is hereby granted, provided that the above copyright
 * notice appear in all copies.  The University of California
 * makes no representations about the suitability of this
 * software for any purpose.  It is provided "as is" without
 * express or implied warranty.
 */

/************************************************************
Copyright 1987 by Sun Microsystems, Inc. Mountain View, CA.

                    All Rights Reserved

Permission  to  use,  copy,  modify,  and  distribute   this
software  and  its documentation for any purpose and without
fee is hereby granted, provided that the above copyright no-
tice  appear  in all copies and that both that copyright no-
tice and this permission notice appear in  supporting  docu-
mentation,  and  that the names of Sun or The Open Group
not be used in advertising or publicity pertaining to 
distribution  of  the software  without specific prior 
written permission. Sun and The Open Group make no 
representations about the suitability of this software for 
any purpose. It is provided "as is" without any express or 
implied warranty.

SUN DISCLAIMS ALL WARRANTIES WITH REGARD TO  THIS  SOFTWARE,
INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FIT-
NESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SUN BE  LI-
ABLE  FOR  ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,  DATA  OR
PROFITS,  WHETHER  IN  AN  ACTION OF CONTRACT, NEGLIGENCE OR
OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION  WITH
THE USE OR PERFORMANCE OF THIS SOFTWARE.

********************************************************/
/*
 * Copyright 1991, 1992, 1993 Kaleb S. Keithley
 *
 * Permission to use, copy, modify, and distribute this
 * software and its documentation for any purpose and without
 * fee is hereby granted, provided that the above copyright
 * notice appear in all copies.  Kaleb S. Keithley makes no 
 * representations about the suitability of this software for 
 * any purpose.  It is provided "as is" without express or 
 * implied warranty.
 */

#define NEED_EVENTS
#include    "sun.h"

Bool sunActiveZaphod = TRUE;

static Bool sunCursorOffScreen();
static void sunCrossScreen();
static void sunWarpCursor();

miPointerScreenFuncRec sunPointerScreenFuncs = {
    sunCursorOffScreen,
    sunCrossScreen,
    sunWarpCursor,
};

/*-
 *-----------------------------------------------------------------------
 * sunMouseCtrl --
 *	Alter the control parameters for the mouse. Since acceleration
 *	etc. is done from the PtrCtrl record in the mouse's device record,
 *	there's nothing to do here.
 *
 * Results:
 *	None.
 *
 * Side Effects:
 *	None.
 *
 *-----------------------------------------------------------------------
 */
/*ARGSUSED*/
static 
void sunMouseCtrl (
    DeviceIntPtr    device,
    PtrCtrl*	    ctrl)
{
}

/*-
 *-----------------------------------------------------------------------
 * sunMouseProc --
 *	Handle the initialization, etc. of a mouse
 *
 * Results:
 *	none.
 *
 * Side Effects:
 *
 * Note:
 *	When using sunwindows, all input comes off a single fd, stored in the
 *	global windowFd.  Therefore, only one device should be enabled and
 *	disabled, even though the application still sees both mouse and
 *	keyboard.  We have arbitrarily chosen to enable and disable windowFd
 *	in the keyboard routine sunKbdProc rather than in sunMouseProc.
 *
 *-----------------------------------------------------------------------
 */
int sunMouseProc (
    DeviceIntPtr  device,
    int	    	  what)
{
    struct termio tty;
    DevicePtr	  pMouse = (DevicePtr) device;
    int	    	  format;
    static int	  oformat;
    BYTE    	  map[4];
    char	  *dev;

    switch (what) {
	case DEVICE_INIT:
	    if (pMouse != LookupPointerDevice()) {
		ErrorF ("Cannot open non-system mouse");	
		return !Success;
	    }
	    if (sunPtrPriv.fd == -1)
		return !Success;
	    pMouse->devicePrivate = (pointer) &sunPtrPriv;
	    pMouse->on = FALSE;
	    map[1] = 1;
	    map[2] = 2;
	    map[3] = 3;
	    InitPointerDeviceStruct(
		pMouse, map, 3, miPointerGetMotionEvents,
 		sunMouseCtrl, miPointerGetMotionBufferSize());
	    break;

	case DEVICE_ON:
	    /* set mouse to raw mode */
	    if (ioctl(sunPtrPriv.fd, TCGETA, &tty) != -1) {
	        tty.c_iflag = (IGNPAR | IGNBRK) & (~PARMRK) & (~ISTRIP);
		tty.c_oflag = 0;
		tty.c_cflag = CREAD | CS8;
		tty.c_lflag = 0;
		tty.c_line = 0;
		tty.c_cc[VTIME] = 0;
		tty.c_cc[VMIN] = 0;
		if (ioctl(sunPtrPriv.fd, TCSETAW, &tty) < 0)
		    perror("ioctl TCSETAW");
	    } else
		perror("ioctl TCGETA");
	    sunPtrPriv.bmask = 0;
	    AddEnabledDevice (sunPtrPriv.fd);
	    pMouse->on = TRUE;
	    break;

	case DEVICE_CLOSE:
	    pMouse->on = FALSE;
	    break;

	case DEVICE_OFF:
	    pMouse->on = FALSE;
	    RemoveEnabledDevice (sunPtrPriv.fd);
	    break;
    }
    return Success;
}

/* mouse protocol code from XFree86 */

#define P_MS		0			/* Microsoft */
#define P_MSC		1			/* Mouse Systems Corp */
#define P_MM		2			/* MMseries */
#define P_LOGI		3			/* Logitech */
#define P_BM		4			/* BusMouse ??? */
#define P_LOGIMAN	5			/* MouseMan / TrackMan
						   [CHRIS-211092] */
#define P_PS2		6			/* PS/2 mouse */
#define P_MMHIT		7			/* MM_HitTab */

static int
xf86MouseProtocol(rBuf, nBytes, evBuf)
     unsigned char *rBuf;
     int nBytes;
     Firm_event evBuf[];
{
  int                  i, buttons, dx, dy;
  static int           pBufP = 0;
  static unsigned char pBuf[8];
  static int lastButtons;
  int change;
  int numEvents = 0;

  const int mseType = P_MSC;
  const int chordMiddle = 0;

  static unsigned char proto[8][5] = {
    /*  hd_mask hd_id   dp_mask dp_id   nobytes */
    { 	0x40,	0x40,	0x40,	0x00,	3 	},  /* MicroSoft */
    {	0xf8,	0x80,	0x00,	0x00,	5	},  /* MouseSystems */
    {	0xe0,	0x80,	0x80,	0x00,	3	},  /* MMSeries */
    {	0xe0,	0x80,	0x80,	0x00,	3	},  /* Logitech */
    {	0xf8,	0x80,	0x00,	0x00,	5	},  /* BusMouse */
    { 	0x40,	0x40,	0x40,	0x00,	3 	},  /* MouseMan
                                                       [CHRIS-211092] */
    {	0xc0,	0x00,	0x00,	0x00,	3	},  /* PS/2 mouse */
    {	0xe0,	0x80,	0x80,	0x00,	3	},  /* MM_HitTablet */
  };
  
  for ( i=0; i < nBytes; i++) {
    /*
     * Hack for resyncing: We check here for a package that is:
     *  a) illegal (detected by wrong data-package header)
     *  b) invalid (0x80 == -128 and that might be wrong for MouseSystems)
     *  c) bad header-package
     *
     * NOTE: b) is a voilation of the MouseSystems-Protocol, since values of
     *       -128 are allowed, but since they are very seldom we can easily
     *       use them as package-header with no button pressed.
     * NOTE/2: On a PS/2 mouse any byte is valid as a data byte. Furthermore,
     *         0x80 is not valid as a header byte. For a PS/2 mouse we skip
     *         checking data bytes.
     *         For resyncing a PS/2 mouse we require the two most significant
     *         bits in the header byte to be 0. These are the overflow bits,
     *         and in case of an overflow we actually lose sync. Overflows
     *         are very rare, however, and we quickly gain sync again after
     *         an overflow condition. This is the best we can do. (Actually,
     *         we could use bit 0x08 in the header byte for resyncing, since
     *         that bit is supposed to be always on, but nobody told
     *         Microsoft...)
     */
    if (pBufP != 0 && mseType != P_PS2 &&
	((rBuf[i] & proto[mseType][2]) != proto[mseType][3]
	 || rBuf[i] == 0x80))
      {
	pBufP = 0;          /* skip package */
      }

    if (pBufP == 0 &&
	(rBuf[i] & proto[mseType][0]) != proto[mseType][1])
      {
	/*
	 * Hack for Logitech MouseMan Mouse - Middle button
	 *
	 * Unfortunately this mouse has variable length packets: the standard
	 * Microsoft 3 byte packet plus an optional 4th byte whenever the
	 * middle button status changes.
	 *
	 * We have already processed the standard packet with the movement
	 * and button info.  Now post an event message with the old status
	 * of the left and right buttons and the updated middle button.
	 */

        /*
	 * Even worse, different MouseMen and TrackMen differ in the 4th
         * byte: some will send 0x00/0x20, others 0x01/0x21, or even
         * 0x02/0x22, so I have to strip off the lower bits. [CHRIS-211092]
	 */
	if ((mseType == P_MS || mseType == P_LOGIMAN)
          && (char)(rBuf[i] & ~0x23) == 0)
	  {
	    buttons = ((int)(rBuf[i] & 0x20) >> 4)
	      | (lastButtons & 0x05);

	    change = buttons ^ lastButtons;
	    /* a little naive, but sufficient for now */
	    if (change & 4)
	    {
	     evBuf[numEvents].id = MS_LEFT;
	     evBuf[numEvents].value = (buttons & 4) ? VKEY_DOWN : VKEY_UP;
	     ++numEvents;
	    }
	    if (change & 2)
	    {
	     evBuf[numEvents].id = MS_MIDDLE;
	     evBuf[numEvents].value = (buttons & 2) ? VKEY_DOWN : VKEY_UP;
	     ++numEvents;
	    }
	    if (change & 1)
	    {
	     evBuf[numEvents].id = MS_RIGHT;
	     evBuf[numEvents].value = (buttons & 1) ? VKEY_DOWN : VKEY_UP;
	     ++numEvents;
	    }
	    lastButtons = buttons;
	  }

	continue;            /* skip package */
      }


    pBuf[pBufP++] = rBuf[i];
    if (pBufP != proto[mseType][4]) continue;


    /*
     * assembly full package
     */
    switch(mseType) {
      
    case P_LOGIMAN:	    /* MouseMan / TrackMan   [CHRIS-211092] */
    case P_MS:              /* Microsoft */
      if (chordMiddle)
	buttons = (((int) pBuf[0] & 0x30) == 0x30) ? 2 :
		  ((int)(pBuf[0] & 0x20) >> 3)
		  | ((int)(pBuf[0] & 0x10) >> 4);
      else {
        buttons = (lastButtons & 2)
		  | ((int)(pBuf[0] & 0x20) >> 3)
		  | ((int)(pBuf[0] & 0x10) >> 4);
      }
      dx = (char)((pBuf[0] & 0x03) << 6) | (pBuf[1] & 0x3F);
      dy = (char)((pBuf[0] & 0x0C) << 4) | (pBuf[2] & 0x3F);
      break;
      
    case P_MSC:             /* Mouse Systems Corp */
      buttons = (~pBuf[0]) & 0x07;
      dx =    (char)(pBuf[1]) + (char)(pBuf[3]);
      dy = - ((char)(pBuf[2]) + (char)(pBuf[4]));
      break;

      
    case P_MMHIT:           /* MM_HitTablet */
      buttons = pBuf[0] & 0x07;
      if (buttons != 0)
        buttons = 1 << (buttons - 1);
      dx = (pBuf[0] & 0x10) ?   pBuf[1] : - pBuf[1];
      dy = (pBuf[0] & 0x08) ? - pBuf[2] :   pBuf[2];
      break;

    case P_MM:              /* MM Series */
    case P_LOGI:            /* Logitech Mice */
      buttons = pBuf[0] & 0x07;
      dx = (pBuf[0] & 0x10) ?   pBuf[1] : - pBuf[1];
      dy = (pBuf[0] & 0x08) ? - pBuf[2] :   pBuf[2];
      break;
      
    case P_BM:              /* BusMouse */
      buttons = (~pBuf[0]) & 0x07;
      dx =   pBuf[1];
      dy = - pBuf[2];
      break;

    case P_PS2:		    /* PS/2 mouse */
      buttons = (pBuf[0] & 0x04) >> 1 |       /* Middle */
	        (pBuf[0] & 0x02) >> 1 |       /* Right */
		(pBuf[0] & 0x01) << 2;        /* Left */
      dx = (pBuf[0] & 0x10) ?    pBuf[1]-256  :  pBuf[1];
      dy = (pBuf[0] & 0x20) ?  -(pBuf[2]-256) : -pBuf[2];
      break;
    }

    /* a little naive, but sufficient for now */
    change = buttons ^ lastButtons;
    if (change & 4)
    {
     evBuf[numEvents].id = MS_LEFT;
     evBuf[numEvents].value = (buttons & 4) ? VKEY_DOWN : VKEY_UP;
     ++numEvents;
    }
    if (change & 2)
    {
     evBuf[numEvents].id = MS_MIDDLE;
     evBuf[numEvents].value = (buttons & 2) ? VKEY_DOWN : VKEY_UP;
     ++numEvents;
    }
    if (change & 1)
    {
     evBuf[numEvents].id = MS_RIGHT;
     evBuf[numEvents].value = (buttons & 1) ? VKEY_DOWN : VKEY_UP;
     ++numEvents;
    }
    lastButtons = buttons;

    if (dx)
    {
     evBuf[numEvents].id = LOC_X_DELTA;
     evBuf[numEvents].value = dx;
     ++numEvents;
    }
    if (dy)
    {
     evBuf[numEvents].id = LOC_Y_DELTA;
     evBuf[numEvents].value = -dy;
     ++numEvents;
    }
    pBufP = 0;
  }
  return numEvents;
}
    
/*-
 *-----------------------------------------------------------------------
 * sunMouseGetEvents --
 *	Return the events waiting in the wings for the given mouse.
 *
 * Results:
 *	A pointer to an array of Firm_events or (Firm_event *)0 if no events
 *	The number of events contained in the array.
 *	A boolean as to whether more events might be available.
 *
 * Side Effects:
 *	None.
 *-----------------------------------------------------------------------
 */

Firm_event* sunMouseGetEvents (
    int		fd,
    Bool	on,
    int*	pNumEvents,
    Bool*	pAgain)
{
    static Firm_event	evBuf[MAXEVENTS];   /* Buffer for Firm_events */
    int	 nBytes;	    /* number of bytes available. */
    char buf[8];

    if ((nBytes = read(fd, buf, sizeof(buf))) == -1) {
   	if (errno == EWOULDBLOCK || errno == EAGAIN || errno == EINTR) {
    	    *pNumEvents = 0;
    	    if (errno == EINTR)
    	    	*pAgain = TRUE;
    	    else
	    	*pAgain = FALSE;
    	} else {
	    Error ("sunMouseGetEvents read");
	    FatalError ("Could not read from mouse");
    	}
    } else {
	if (on) {
	    *pAgain = (nBytes == sizeof(buf)); /* very unlikely... */
	    if (*pNumEvents = xf86MouseProtocol(buf, nBytes, evBuf))
	    {
		struct timeval now;
		int i;

		X_GETTIMEOFDAY(&now);
		for (i=0;i<*pNumEvents;i++)
		    evBuf[i].time = now;
	    }
	} else {
	    *pNumEvents = 0;
	    *pAgain = FALSE;
	}
    }
    return evBuf;
}


/*-
 *-----------------------------------------------------------------------
 * MouseAccelerate --
 *	Given a delta and a mouse, return the acceleration of the delta.
 *
 * Results:
 *	The corrected delta
 *
 * Side Effects:
 *	None.
 *
 *-----------------------------------------------------------------------
 */
static short
MouseAccelerate (device, delta)
    DeviceIntPtr  device;
    int	    	  delta;
{
    int  sgn = sign(delta);
    PtrCtrl *pCtrl;
    short ret;

    delta = abs(delta);
    pCtrl = &device->ptrfeed->ctrl;
    if (delta > pCtrl->threshold) {
	ret = 
	    (short) sgn * 
		(pCtrl->threshold + ((delta - pCtrl->threshold) * pCtrl->num) /
		    pCtrl->den);
    } else {
	ret = (short) sgn * delta;
    }
    return ret;
}

/*-
 *-----------------------------------------------------------------------
 * sunMouseEnqueueEvent --
 *	Given a Firm_event for a mouse, pass it off the the dix layer
 *	properly converted...
 *
 * Results:
 *	None.
 *
 * Side Effects:
 *	The cursor may be redrawn...? devPrivate/x/y will be altered.
 *
 *-----------------------------------------------------------------------
 */

void sunMouseEnqueueEvent (
    DeviceIntPtr  device,
    Firm_event	  *fe)
{
    xEvent		xE;
    sunPtrPrivPtr	pPriv;	/* Private data for pointer */
    int			bmask;	/* Temporary button mask */
    unsigned long	time;
    int			x, y;

    pPriv = (sunPtrPrivPtr)device->public.devicePrivate;

    time = xE.u.keyButtonPointer.time = TVTOMILLI(fe->time);

    switch (fe->id) {
    case MS_LEFT:
    case MS_MIDDLE:
    case MS_RIGHT:
	/*
	 * A button changed state. Sometimes we will get two events
	 * for a single state change. Should we get a button event which
	 * reflects the current state of affairs, that event is discarded.
	 *
	 * Mouse buttons start at 1.
	 */
	xE.u.u.detail = (fe->id - MS_LEFT) + 1;
	bmask = 1 << xE.u.u.detail;
	if (fe->value == VKEY_UP) {
	    if (pPriv->bmask & bmask) {
		xE.u.u.type = ButtonRelease;
		pPriv->bmask &= ~bmask;
	    } else {
		return;
	    }
	} else {
	    if ((pPriv->bmask & bmask) == 0) {
		xE.u.u.type = ButtonPress;
		pPriv->bmask |= bmask;
	    } else {
		return;
	    }
	}
	mieqEnqueue (&xE);
	break;
    case LOC_X_DELTA:
	miPointerDeltaCursor (MouseAccelerate(device,fe->value),0,time);
	break;
    case LOC_Y_DELTA:
	/*
	 * For some reason, motion up generates a positive y delta
	 * and motion down a negative delta, so we must subtract
	 * here instead of add...
	 */
	miPointerDeltaCursor (0,-MouseAccelerate(device,fe->value),time);
	break;
    case LOC_X_ABSOLUTE:
	miPointerPosition (&x, &y);
	miPointerAbsoluteCursor (fe->value, y, time);
	break;
    case LOC_Y_ABSOLUTE:
	miPointerPosition (&x, &y);
	miPointerAbsoluteCursor (x, fe->value, time);
	break;
    default:
	FatalError ("sunMouseEnqueueEvent: unrecognized id\n");
	break;
    }
}

/*ARGSUSED*/
static Bool
sunCursorOffScreen (pScreen, x, y)
    ScreenPtr	*pScreen;
    int		*x, *y;
{
    int	    index, ret = FALSE;
    extern Bool PointerConfinedToScreen();

    if (PointerConfinedToScreen()) return TRUE;
    /*
     * Active Zaphod implementation:
     *    increment or decrement the current screen
     *    if the x is to the right or the left of
     *    the current screen.
     */
    if (sunActiveZaphod &&
	screenInfo.numScreens > 1 && (*x >= (*pScreen)->width || *x < 0)) {
	index = (*pScreen)->myNum;
	if (*x < 0) {
	    index = (index ? index : screenInfo.numScreens) - 1;
	    *pScreen = screenInfo.screens[index];
	    *x += (*pScreen)->width;
	} else {
	    *x -= (*pScreen)->width;
	    index = (index + 1) % screenInfo.numScreens;
	    *pScreen = screenInfo.screens[index];
	}
	ret = TRUE;
    }
    return ret;
}

static void
sunCrossScreen (pScreen, entering)
    ScreenPtr	pScreen;
    Bool	entering;
{
    if (sunFbs[pScreen->myNum].EnterLeave)
	(*sunFbs[pScreen->myNum].EnterLeave) (pScreen, entering ? 0 : 1);
}

static void
sunWarpCursor (pScreen, x, y)
    ScreenPtr	pScreen;
    int		x, y;
{
    sigset_t newsigmask;

    (void) sigemptyset (&newsigmask);
    (void) sigaddset (&newsigmask, SIGIO);
    (void) sigprocmask (SIG_BLOCK, &newsigmask, (sigset_t *)NULL);
    miPointerWarpCursor (pScreen, x, y);
    (void) sigprocmask (SIG_UNBLOCK, &newsigmask, (sigset_t *)NULL);
}