This repository has been archived by the owner on Feb 11, 2021. It is now read-only.
/
SDL_events.c
620 lines (543 loc) · 15.4 KB
1
2
/*
SDL - Simple DirectMedia Layer
3
Copyright (C) 1997-2010 Sam Lantinga
4
5
This library is free software; you can redistribute it and/or
6
modify it under the terms of the GNU Lesser General Public
7
License as published by the Free Software Foundation; either
8
version 2.1 of the License, or (at your option) any later version.
9
10
11
12
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13
Lesser General Public License for more details.
14
15
16
17
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18
19
Sam Lantinga
20
slouken@libsdl.org
21
*/
22
#include "SDL_config.h"
23
24
25
26
/* General event handling code for SDL */
#include "SDL.h"
27
#include "SDL_events.h"
28
#include "SDL_syswm.h"
29
#include "SDL_thread.h"
30
#include "SDL_sysevents.h"
31
32
33
34
35
#include "SDL_events_c.h"
#include "../timer/SDL_timer_c.h"
#if !SDL_JOYSTICK_DISABLED
#include "../joystick/SDL_joystick_c.h"
#endif
36
37
38
/* Public data -- the event filter */
SDL_EventFilter SDL_EventOK = NULL;
39
void *SDL_EventOKParam;
40
41
42
43
44
45
46
typedef struct {
Uint32 bits[8];
} SDL_DisabledEventBlock;
static SDL_DisabledEventBlock *SDL_disabled_events[256];
static Uint32 SDL_userevents = SDL_USEREVENT;
47
48
49
/* Private data -- event queue */
#define MAXEVENTS 128
50
51
52
53
54
55
56
57
58
static struct
{
SDL_mutex *lock;
int active;
int head;
int tail;
SDL_Event event[MAXEVENTS];
int wmmsg_next;
struct SDL_SysWMmsg wmmsg[MAXEVENTS];
59
60
61
} SDL_EventQ;
/* Private data -- event locking structure */
62
63
64
65
static struct
{
SDL_mutex *lock;
int safe;
66
67
68
} SDL_EventLock;
/* Thread functions */
69
static SDL_Thread *SDL_EventThread = NULL; /* Thread handle */
70
static SDL_threadID event_thread; /* The event thread id */
71
72
73
void
SDL_Lock_EventThread(void)
74
{
75
76
77
78
79
80
81
if (SDL_EventThread && (SDL_ThreadID() != event_thread)) {
/* Grab lock and spin until we're sure event thread stopped */
SDL_mutexP(SDL_EventLock.lock);
while (!SDL_EventLock.safe) {
SDL_Delay(1);
}
}
82
}
83
84
85
void
SDL_Unlock_EventThread(void)
86
{
87
88
89
if (SDL_EventThread && (SDL_ThreadID() != event_thread)) {
SDL_mutexV(SDL_EventLock.lock);
}
90
91
}
92
93
94
static __inline__ SDL_bool
SDL_ShouldPollJoystick()
{
95
#if !SDL_JOYSTICK_DISABLED
96
97
98
99
100
if (SDL_numjoysticks &&
(!SDL_disabled_events[SDL_JOYAXISMOTION >> 8] ||
SDL_JoystickEventState(SDL_QUERY))) {
return SDL_TRUE;
}
101
#endif
102
103
104
return SDL_FALSE;
}
105
106
static int SDLCALL
SDL_GobbleEvents(void *unused)
107
{
108
event_thread = SDL_ThreadID();
109
110
111
while (SDL_EventQ.active) {
SDL_VideoDevice *_this = SDL_GetVideoDevice();
112
113
114
115
116
/* Get events from the video subsystem */
if (_this) {
_this->PumpEvents(_this);
}
117
#if !SDL_JOYSTICK_DISABLED
118
/* Check for joystick state change */
119
if (SDL_ShouldPollJoystick()) {
120
121
SDL_JoystickUpdate();
}
122
123
#endif
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
/* Give up the CPU for the rest of our timeslice */
SDL_EventLock.safe = 1;
if (SDL_timer_running) {
SDL_ThreadedTimerCheck();
}
SDL_Delay(1);
/* Check for event locking.
On the P of the lock mutex, if the lock is held, this thread
will wait until the lock is released before continuing. The
safe flag will be set, meaning that the other thread can go
about it's business. The safe flag is reset before the V,
so as soon as the mutex is free, other threads can see that
it's not safe to interfere with the event thread.
*/
SDL_mutexP(SDL_EventLock.lock);
SDL_EventLock.safe = 0;
SDL_mutexV(SDL_EventLock.lock);
}
SDL_SetTimerThreaded(0);
event_thread = 0;
return (0);
146
147
}
148
149
static int
SDL_StartEventThread(Uint32 flags)
150
{
151
152
153
/* Reset everything to zero */
SDL_EventThread = NULL;
SDL_memset(&SDL_EventLock, 0, sizeof(SDL_EventLock));
154
155
/* Create the lock and set ourselves active */
156
#if !SDL_THREADS_DISABLED
157
158
159
160
SDL_EventQ.lock = SDL_CreateMutex();
if (SDL_EventQ.lock == NULL) {
return (-1);
}
161
#endif /* !SDL_THREADS_DISABLED */
162
SDL_EventQ.active = 1;
163
164
165
166
167
168
169
if ((flags & SDL_INIT_EVENTTHREAD) == SDL_INIT_EVENTTHREAD) {
SDL_EventLock.lock = SDL_CreateMutex();
if (SDL_EventLock.lock == NULL) {
return (-1);
}
SDL_EventLock.safe = 0;
170
171
172
/* The event thread will handle timers too */
SDL_SetTimerThreaded(2);
173
#if (defined(__WIN32__) && !defined(_WIN32_WCE)) && !defined(HAVE_LIBC)
174
#undef SDL_CreateThread
175
176
SDL_EventThread =
SDL_CreateThread(SDL_GobbleEvents, NULL, NULL, NULL);
177
#else
178
SDL_EventThread = SDL_CreateThread(SDL_GobbleEvents, NULL);
179
#endif
180
181
182
183
184
185
186
if (SDL_EventThread == NULL) {
return (-1);
}
} else {
event_thread = 0;
}
return (0);
187
188
}
189
190
static void
SDL_StopEventThread(void)
191
{
192
193
194
195
196
SDL_EventQ.active = 0;
if (SDL_EventThread) {
SDL_WaitThread(SDL_EventThread, NULL);
SDL_EventThread = NULL;
SDL_DestroyMutex(SDL_EventLock.lock);
197
SDL_EventLock.lock = NULL;
198
}
199
200
201
202
if (SDL_EventQ.lock) {
SDL_DestroyMutex(SDL_EventQ.lock);
SDL_EventQ.lock = NULL;
}
203
204
}
205
SDL_threadID
206
SDL_EventThreadID(void)
207
{
208
return (event_thread);
209
210
211
212
}
/* Public functions */
213
214
void
SDL_StopEventLoop(void)
215
{
216
217
int i;
218
219
220
221
222
223
224
225
226
227
228
229
/* Halt the event thread, if running */
SDL_StopEventThread();
/* Shutdown event handlers */
SDL_KeyboardQuit();
SDL_MouseQuit();
SDL_QuitQuit();
/* Clean out EventQ */
SDL_EventQ.head = 0;
SDL_EventQ.tail = 0;
SDL_EventQ.wmmsg_next = 0;
230
231
232
233
234
235
236
237
/* Clear disabled event state */
for (i = 0; i < SDL_arraysize(SDL_disabled_events); ++i) {
if (SDL_disabled_events[i]) {
SDL_free(SDL_disabled_events[i]);
SDL_disabled_events[i] = NULL;
}
}
238
239
240
}
/* This function (and associated calls) may be called more than once */
241
242
int
SDL_StartEventLoop(Uint32 flags)
243
{
244
245
246
247
248
249
250
251
252
int retcode;
/* Clean out the event queue */
SDL_EventThread = NULL;
SDL_EventQ.lock = NULL;
SDL_StopEventLoop();
/* No filter to start with, process most event types */
SDL_EventOK = NULL;
253
SDL_EventState(SDL_SYSWMEVENT, SDL_DISABLE);
254
255
256
257
258
/* Initialize event handlers */
retcode = 0;
retcode += SDL_KeyboardInit();
retcode += SDL_MouseInit();
259
retcode += SDL_TouchInit();
260
261
262
263
264
265
266
267
268
269
270
271
retcode += SDL_QuitInit();
if (retcode < 0) {
/* We don't expect them to fail, but... */
return (-1);
}
/* Create the lock and event thread */
if (SDL_StartEventThread(flags) < 0) {
SDL_StopEventLoop();
return (-1);
}
return (0);
272
273
274
275
}
/* Add an event to the event queue -- called with the queue locked */
276
277
static int
SDL_AddEvent(SDL_Event * event)
278
{
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
int tail, added;
tail = (SDL_EventQ.tail + 1) % MAXEVENTS;
if (tail == SDL_EventQ.head) {
/* Overflow, drop event */
added = 0;
} else {
SDL_EventQ.event[SDL_EventQ.tail] = *event;
if (event->type == SDL_SYSWMEVENT) {
/* Note that it's possible to lose an event */
int next = SDL_EventQ.wmmsg_next;
SDL_EventQ.wmmsg[next] = *event->syswm.msg;
SDL_EventQ.event[SDL_EventQ.tail].syswm.msg =
&SDL_EventQ.wmmsg[next];
SDL_EventQ.wmmsg_next = (next + 1) % MAXEVENTS;
}
SDL_EventQ.tail = tail;
added = 1;
}
return (added);
299
300
301
302
}
/* Cut an event, and return the next valid spot, or the tail */
/* -- called with the queue locked */
303
304
static int
SDL_CutEvent(int spot)
305
{
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
if (spot == SDL_EventQ.head) {
SDL_EventQ.head = (SDL_EventQ.head + 1) % MAXEVENTS;
return (SDL_EventQ.head);
} else if ((spot + 1) % MAXEVENTS == SDL_EventQ.tail) {
SDL_EventQ.tail = spot;
return (SDL_EventQ.tail);
} else
/* We cut the middle -- shift everything over */
{
int here, next;
/* This can probably be optimized with SDL_memcpy() -- careful! */
if (--SDL_EventQ.tail < 0) {
SDL_EventQ.tail = MAXEVENTS - 1;
}
for (here = spot; here != SDL_EventQ.tail; here = next) {
next = (here + 1) % MAXEVENTS;
SDL_EventQ.event[here] = SDL_EventQ.event[next];
}
return (spot);
}
/* NOTREACHED */
328
329
330
}
/* Lock the event queue, take a peep at it, and unlock it */
331
332
int
SDL_PeepEvents(SDL_Event * events, int numevents, SDL_eventaction action,
333
Uint32 minType, Uint32 maxType)
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
{
int i, used;
/* Don't look after we've quit */
if (!SDL_EventQ.active) {
return (-1);
}
/* Lock the event queue */
used = 0;
if (SDL_mutexP(SDL_EventQ.lock) == 0) {
if (action == SDL_ADDEVENT) {
for (i = 0; i < numevents; ++i) {
used += SDL_AddEvent(&events[i]);
}
} else {
SDL_Event tmpevent;
int spot;
/* If 'events' is NULL, just see if they exist */
if (events == NULL) {
action = SDL_PEEKEVENT;
numevents = 1;
events = &tmpevent;
}
spot = SDL_EventQ.head;
while ((used < numevents) && (spot != SDL_EventQ.tail)) {
360
361
Uint32 type = SDL_EventQ.event[spot].type;
if (minType <= type && type <= maxType) {
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
events[used++] = SDL_EventQ.event[spot];
if (action == SDL_GETEVENT) {
spot = SDL_CutEvent(spot);
} else {
spot = (spot + 1) % MAXEVENTS;
}
} else {
spot = (spot + 1) % MAXEVENTS;
}
}
}
SDL_mutexV(SDL_EventQ.lock);
} else {
SDL_SetError("Couldn't lock event queue");
used = -1;
}
return (used);
}
SDL_bool
382
383
384
385
386
387
388
SDL_HasEvent(Uint32 type)
{
return (SDL_PeepEvents(NULL, 0, SDL_PEEKEVENT, type, type) > 0);
}
SDL_bool
SDL_HasEvents(Uint32 minType, Uint32 maxType)
389
{
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
return (SDL_PeepEvents(NULL, 0, SDL_PEEKEVENT, minType, maxType) > 0);
}
void
SDL_FlushEvent(Uint32 type)
{
SDL_FlushEvents(type, type);
}
void
SDL_FlushEvents(Uint32 minType, Uint32 maxType)
{
/* Don't look after we've quit */
if (!SDL_EventQ.active) {
return;
}
407
408
409
/* Make sure the events are current */
SDL_PumpEvents();
410
411
412
413
414
415
416
417
418
419
420
421
422
/* Lock the event queue */
if (SDL_mutexP(SDL_EventQ.lock) == 0) {
int spot = SDL_EventQ.head;
while (spot != SDL_EventQ.tail) {
Uint32 type = SDL_EventQ.event[spot].type;
if (minType <= type && type <= maxType) {
spot = SDL_CutEvent(spot);
} else {
spot = (spot + 1) % MAXEVENTS;
}
}
SDL_mutexV(SDL_EventQ.lock);
}
423
424
425
}
/* Run the system dependent event loops */
426
427
void
SDL_PumpEvents(void)
428
{
429
430
if (!SDL_EventThread) {
SDL_VideoDevice *_this = SDL_GetVideoDevice();
431
432
433
434
435
/* Get events from the video subsystem */
if (_this) {
_this->PumpEvents(_this);
}
436
#if !SDL_JOYSTICK_DISABLED
437
/* Check for joystick state change */
438
if (SDL_ShouldPollJoystick()) {
439
440
SDL_JoystickUpdate();
}
441
#endif
442
}
443
444
445
446
}
/* Public functions */
447
448
int
SDL_PollEvent(SDL_Event * event)
449
{
450
return SDL_WaitEventTimeout(event, 0);
451
452
}
453
454
int
SDL_WaitEvent(SDL_Event * event)
455
{
456
457
458
459
460
461
462
463
464
465
466
467
return SDL_WaitEventTimeout(event, -1);
}
int
SDL_WaitEventTimeout(SDL_Event * event, int timeout)
{
Uint32 expiration = 0;
if (timeout > 0)
expiration = SDL_GetTicks() + timeout;
for (;;) {
468
SDL_PumpEvents();
469
switch (SDL_PeepEvents(event, 1, SDL_GETEVENT, SDL_FIRSTEVENT, SDL_LASTEVENT)) {
470
471
472
473
474
case -1:
return 0;
case 1:
return 1;
case 0:
475
476
477
478
479
480
481
482
if (timeout == 0) {
/* Polling and no events, just return */
return 0;
}
if (timeout > 0 && ((int) (SDL_GetTicks() - expiration) >= 0)) {
/* Timeout expired and no events */
return 0;
}
483
SDL_Delay(10);
484
break;
485
486
}
}
487
488
}
489
490
int
SDL_PushEvent(SDL_Event * event)
491
{
492
493
494
if (SDL_EventOK && !SDL_EventOK(SDL_EventOKParam, event)) {
return 0;
}
495
if (SDL_PeepEvents(event, 1, SDL_ADDEVENT, 0, 0) <= 0) {
496
497
return -1;
}
498
499
500
501
SDL_GestureProcessEvent(event);
502
return 1;
503
504
}
505
506
void
SDL_SetEventFilter(SDL_EventFilter filter, void *userdata)
507
{
508
SDL_Event bitbucket;
509
510
511
512
513
/* Set filter and discard pending events */
SDL_EventOK = filter;
SDL_EventOKParam = userdata;
while (SDL_PollEvent(&bitbucket) > 0);
514
515
}
516
517
SDL_bool
SDL_GetEventFilter(SDL_EventFilter * filter, void **userdata)
518
{
519
520
521
522
523
524
525
if (filter) {
*filter = SDL_EventOK;
}
if (userdata) {
*userdata = SDL_EventOKParam;
}
return SDL_EventOK ? SDL_TRUE : SDL_FALSE;
526
527
}
528
529
void
SDL_FilterEvents(SDL_EventFilter filter, void *userdata)
530
{
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
if (SDL_mutexP(SDL_EventQ.lock) == 0) {
int spot;
spot = SDL_EventQ.head;
while (spot != SDL_EventQ.tail) {
if (filter(userdata, &SDL_EventQ.event[spot])) {
spot = (spot + 1) % MAXEVENTS;
} else {
spot = SDL_CutEvent(spot);
}
}
}
SDL_mutexV(SDL_EventQ.lock);
}
Uint8
547
SDL_EventState(Uint32 type, int state)
548
549
{
Uint8 current_state;
550
551
Uint8 hi = ((type >> 8) & 0xff);
Uint8 lo = (type & 0xff);
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
if (SDL_disabled_events[hi] &&
(SDL_disabled_events[hi]->bits[lo/32] & (1 << (lo&31)))) {
current_state = SDL_DISABLE;
} else {
current_state = SDL_ENABLE;
}
if (state != current_state)
{
switch (state) {
case SDL_DISABLE:
/* Disable this event type and discard pending events */
if (!SDL_disabled_events[hi]) {
SDL_disabled_events[hi] = (SDL_DisabledEventBlock*) SDL_calloc(1, sizeof(SDL_DisabledEventBlock));
if (!SDL_disabled_events[hi]) {
/* Out of memory, nothing we can do... */
break;
}
571
}
572
573
574
575
576
577
578
579
580
SDL_disabled_events[hi]->bits[lo/32] |= (1 << (lo&31));
SDL_FlushEvent(type);
break;
case SDL_ENABLE:
SDL_disabled_events[hi]->bits[lo/32] &= ~(1 << (lo&31));
break;
default:
/* Querying state... */
break;
581
582
583
}
}
584
585
586
587
588
589
590
591
592
593
594
595
596
return current_state;
}
Uint32
SDL_RegisterEvents(int numevents)
{
Uint32 event_base;
if (SDL_userevents+numevents <= SDL_LASTEVENT) {
event_base = SDL_userevents;
SDL_userevents += numevents;
} else {
event_base = (Uint32)-1;
597
}
598
return event_base;
599
600
601
602
}
/* This is a generic event handler.
*/
603
604
int
SDL_SendSysWMEvent(SDL_SysWMmsg * message)
605
{
606
607
608
int posted;
posted = 0;
609
if (SDL_GetEventState(SDL_SYSWMEVENT) == SDL_ENABLE) {
610
611
612
613
614
615
616
617
SDL_Event event;
SDL_memset(&event, 0, sizeof(event));
event.type = SDL_SYSWMEVENT;
event.syswm.msg = message;
posted = (SDL_PushEvent(&event) > 0);
}
/* Update internal event state */
return (posted);
618
}
619
620
/* vi: set ts=4 sw=4 expandtab: */