SDL  2.0
SDL.c
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1 /*
2  Simple DirectMedia Layer
3  Copyright (C) 1997-2019 Sam Lantinga <slouken@libsdl.org>
4 
5  This software is provided 'as-is', without any express or implied
6  warranty. In no event will the authors be held liable for any damages
7  arising from the use of this software.
8 
9  Permission is granted to anyone to use this software for any purpose,
10  including commercial applications, and to alter it and redistribute it
11  freely, subject to the following restrictions:
12 
13  1. The origin of this software must not be misrepresented; you must not
14  claim that you wrote the original software. If you use this software
15  in a product, an acknowledgment in the product documentation would be
16  appreciated but is not required.
17  2. Altered source versions must be plainly marked as such, and must not be
18  misrepresented as being the original software.
19  3. This notice may not be removed or altered from any source distribution.
20 */
21 #include "./SDL_internal.h"
22 
23 #if defined(__WIN32__)
25 #endif
26 
27 /* Initialization code for SDL */
28 
29 #include "SDL.h"
30 #include "SDL_bits.h"
31 #include "SDL_revision.h"
32 #include "SDL_assert_c.h"
33 #include "events/SDL_events_c.h"
34 #include "haptic/SDL_haptic_c.h"
36 #include "sensor/SDL_sensor_c.h"
37 
38 /* Initialization/Cleanup routines */
39 #if !SDL_TIMERS_DISABLED
40 # include "timer/SDL_timer_c.h"
41 #endif
42 #if SDL_VIDEO_DRIVER_WINDOWS
43 extern int SDL_HelperWindowCreate(void);
44 extern int SDL_HelperWindowDestroy(void);
45 #endif
46 
47 
48 /* The initialized subsystems */
49 #ifdef SDL_MAIN_NEEDED
51 #else
53 #endif
56 
57 /* Private helper to increment a subsystem's ref counter. */
58 static void
60 {
61  int subsystem_index = SDL_MostSignificantBitIndex32(subsystem);
62  SDL_assert(SDL_SubsystemRefCount[subsystem_index] < 255);
63  ++SDL_SubsystemRefCount[subsystem_index];
64 }
65 
66 /* Private helper to decrement a subsystem's ref counter. */
67 static void
69 {
70  int subsystem_index = SDL_MostSignificantBitIndex32(subsystem);
71  if (SDL_SubsystemRefCount[subsystem_index] > 0) {
72  --SDL_SubsystemRefCount[subsystem_index];
73  }
74 }
75 
76 /* Private helper to check if a system needs init. */
77 static SDL_bool
79 {
80  int subsystem_index = SDL_MostSignificantBitIndex32(subsystem);
81  SDL_assert(SDL_SubsystemRefCount[subsystem_index] < 255);
82  return (SDL_SubsystemRefCount[subsystem_index] == 0) ? SDL_TRUE : SDL_FALSE;
83 }
84 
85 /* Private helper to check if a system needs to be quit. */
86 static SDL_bool
88  int subsystem_index = SDL_MostSignificantBitIndex32(subsystem);
89  if (SDL_SubsystemRefCount[subsystem_index] == 0) {
90  return SDL_FALSE;
91  }
92 
93  /* If we're in SDL_Quit, we shut down every subsystem, even if refcount
94  * isn't zero.
95  */
96  return (SDL_SubsystemRefCount[subsystem_index] == 1 || SDL_bInMainQuit) ? SDL_TRUE : SDL_FALSE;
97 }
98 
99 void
101 {
103 }
104 
105 int
107 {
108  if (!SDL_MainIsReady) {
109  SDL_SetError("Application didn't initialize properly, did you include SDL_main.h in the file containing your main() function?");
110  return -1;
111  }
112 
113  /* Clear the error message */
114  SDL_ClearError();
115 
116  if ((flags & SDL_INIT_GAMECONTROLLER)) {
117  /* game controller implies joystick */
118  flags |= SDL_INIT_JOYSTICK;
119  }
120 
121  if ((flags & (SDL_INIT_VIDEO|SDL_INIT_JOYSTICK))) {
122  /* video or joystick implies events */
123  flags |= SDL_INIT_EVENTS;
124  }
125 
126 #if SDL_VIDEO_DRIVER_WINDOWS
127  if ((flags & (SDL_INIT_HAPTIC|SDL_INIT_JOYSTICK))) {
128  if (SDL_HelperWindowCreate() < 0) {
129  return -1;
130  }
131  }
132 #endif
133 
134 #if !SDL_TIMERS_DISABLED
135  SDL_TicksInit();
136 #endif
137 
138  /* Initialize the event subsystem */
139  if ((flags & SDL_INIT_EVENTS)) {
140 #if !SDL_EVENTS_DISABLED
141  if (SDL_PrivateShouldInitSubsystem(SDL_INIT_EVENTS)) {
142  if (SDL_EventsInit() < 0) {
143  return (-1);
144  }
145  }
146  SDL_PrivateSubsystemRefCountIncr(SDL_INIT_EVENTS);
147 #else
148  return SDL_SetError("SDL not built with events support");
149 #endif
150  }
151 
152  /* Initialize the timer subsystem */
153  if ((flags & SDL_INIT_TIMER)){
154 #if !SDL_TIMERS_DISABLED
155  if (SDL_PrivateShouldInitSubsystem(SDL_INIT_TIMER)) {
156  if (SDL_TimerInit() < 0) {
157  return (-1);
158  }
159  }
160  SDL_PrivateSubsystemRefCountIncr(SDL_INIT_TIMER);
161 #else
162  return SDL_SetError("SDL not built with timer support");
163 #endif
164  }
165 
166  /* Initialize the video subsystem */
167  if ((flags & SDL_INIT_VIDEO)){
168 #if !SDL_VIDEO_DISABLED
169  if (SDL_PrivateShouldInitSubsystem(SDL_INIT_VIDEO)) {
170  if (SDL_VideoInit(NULL) < 0) {
171  return (-1);
172  }
173  }
174  SDL_PrivateSubsystemRefCountIncr(SDL_INIT_VIDEO);
175 #else
176  return SDL_SetError("SDL not built with video support");
177 #endif
178  }
179 
180  /* Initialize the audio subsystem */
181  if ((flags & SDL_INIT_AUDIO)){
182 #if !SDL_AUDIO_DISABLED
183  if (SDL_PrivateShouldInitSubsystem(SDL_INIT_AUDIO)) {
184  if (SDL_AudioInit(NULL) < 0) {
185  return (-1);
186  }
187  }
188  SDL_PrivateSubsystemRefCountIncr(SDL_INIT_AUDIO);
189 #else
190  return SDL_SetError("SDL not built with audio support");
191 #endif
192  }
193 
194  /* Initialize the joystick subsystem */
195  if ((flags & SDL_INIT_JOYSTICK)){
196 #if !SDL_JOYSTICK_DISABLED
197  if (SDL_PrivateShouldInitSubsystem(SDL_INIT_JOYSTICK)) {
198  if (SDL_JoystickInit() < 0) {
199  return (-1);
200  }
201  }
202  SDL_PrivateSubsystemRefCountIncr(SDL_INIT_JOYSTICK);
203 #else
204  return SDL_SetError("SDL not built with joystick support");
205 #endif
206  }
207 
208  if ((flags & SDL_INIT_GAMECONTROLLER)){
209 #if !SDL_JOYSTICK_DISABLED
210  if (SDL_PrivateShouldInitSubsystem(SDL_INIT_GAMECONTROLLER)) {
211  if (SDL_GameControllerInit() < 0) {
212  return (-1);
213  }
214  }
215  SDL_PrivateSubsystemRefCountIncr(SDL_INIT_GAMECONTROLLER);
216 #else
217  return SDL_SetError("SDL not built with joystick support");
218 #endif
219  }
220 
221  /* Initialize the haptic subsystem */
222  if ((flags & SDL_INIT_HAPTIC)){
223 #if !SDL_HAPTIC_DISABLED
224  if (SDL_PrivateShouldInitSubsystem(SDL_INIT_HAPTIC)) {
225  if (SDL_HapticInit() < 0) {
226  return (-1);
227  }
228  }
229  SDL_PrivateSubsystemRefCountIncr(SDL_INIT_HAPTIC);
230 #else
231  return SDL_SetError("SDL not built with haptic (force feedback) support");
232 #endif
233  }
234 
235  /* Initialize the sensor subsystem */
236  if ((flags & SDL_INIT_SENSOR)){
237 #if !SDL_SENSOR_DISABLED
238  if (SDL_PrivateShouldInitSubsystem(SDL_INIT_SENSOR)) {
239  if (SDL_SensorInit() < 0) {
240  return (-1);
241  }
242  }
243  SDL_PrivateSubsystemRefCountIncr(SDL_INIT_SENSOR);
244 #else
245  return SDL_SetError("SDL not built with sensor support");
246 #endif
247  }
248 
249  return (0);
250 }
251 
252 int
254 {
255  return SDL_InitSubSystem(flags);
256 }
257 
258 void
260 {
261  /* Shut down requested initialized subsystems */
262 #if !SDL_SENSOR_DISABLED
263  if ((flags & SDL_INIT_SENSOR)) {
264  if (SDL_PrivateShouldQuitSubsystem(SDL_INIT_SENSOR)) {
265  SDL_SensorQuit();
266  }
267  SDL_PrivateSubsystemRefCountDecr(SDL_INIT_SENSOR);
268  }
269 #endif
270 
271 #if !SDL_JOYSTICK_DISABLED
272  if ((flags & SDL_INIT_GAMECONTROLLER)) {
273  /* game controller implies joystick */
274  flags |= SDL_INIT_JOYSTICK;
275 
276  if (SDL_PrivateShouldQuitSubsystem(SDL_INIT_GAMECONTROLLER)) {
278  }
279  SDL_PrivateSubsystemRefCountDecr(SDL_INIT_GAMECONTROLLER);
280  }
281 
282  if ((flags & SDL_INIT_JOYSTICK)) {
283  /* joystick implies events */
284  flags |= SDL_INIT_EVENTS;
285 
286  if (SDL_PrivateShouldQuitSubsystem(SDL_INIT_JOYSTICK)) {
288  }
289  SDL_PrivateSubsystemRefCountDecr(SDL_INIT_JOYSTICK);
290  }
291 #endif
292 
293 #if !SDL_HAPTIC_DISABLED
294  if ((flags & SDL_INIT_HAPTIC)) {
295  if (SDL_PrivateShouldQuitSubsystem(SDL_INIT_HAPTIC)) {
296  SDL_HapticQuit();
297  }
298  SDL_PrivateSubsystemRefCountDecr(SDL_INIT_HAPTIC);
299  }
300 #endif
301 
302 #if !SDL_AUDIO_DISABLED
303  if ((flags & SDL_INIT_AUDIO)) {
304  if (SDL_PrivateShouldQuitSubsystem(SDL_INIT_AUDIO)) {
305  SDL_AudioQuit();
306  }
307  SDL_PrivateSubsystemRefCountDecr(SDL_INIT_AUDIO);
308  }
309 #endif
310 
311 #if !SDL_VIDEO_DISABLED
312  if ((flags & SDL_INIT_VIDEO)) {
313  /* video implies events */
314  flags |= SDL_INIT_EVENTS;
315 
316  if (SDL_PrivateShouldQuitSubsystem(SDL_INIT_VIDEO)) {
317  SDL_VideoQuit();
318  }
319  SDL_PrivateSubsystemRefCountDecr(SDL_INIT_VIDEO);
320  }
321 #endif
322 
323 #if !SDL_TIMERS_DISABLED
324  if ((flags & SDL_INIT_TIMER)) {
325  if (SDL_PrivateShouldQuitSubsystem(SDL_INIT_TIMER)) {
326  SDL_TimerQuit();
327  }
328  SDL_PrivateSubsystemRefCountDecr(SDL_INIT_TIMER);
329  }
330 #endif
331 
332 #if !SDL_EVENTS_DISABLED
333  if ((flags & SDL_INIT_EVENTS)) {
334  if (SDL_PrivateShouldQuitSubsystem(SDL_INIT_EVENTS)) {
335  SDL_EventsQuit();
336  }
337  SDL_PrivateSubsystemRefCountDecr(SDL_INIT_EVENTS);
338  }
339 #endif
340 }
341 
342 Uint32
344 {
345  int i;
346  int num_subsystems = SDL_arraysize(SDL_SubsystemRefCount);
347  Uint32 initialized = 0;
348 
349  /* Fast path for checking one flag */
350  if (SDL_HasExactlyOneBitSet32(flags)) {
351  int subsystem_index = SDL_MostSignificantBitIndex32(flags);
352  return SDL_SubsystemRefCount[subsystem_index] ? flags : 0;
353  }
354 
355  if (!flags) {
356  flags = SDL_INIT_EVERYTHING;
357  }
358 
359  num_subsystems = SDL_min(num_subsystems, SDL_MostSignificantBitIndex32(flags) + 1);
360 
361  /* Iterate over each bit in flags, and check the matching subsystem. */
362  for (i = 0; i < num_subsystems; ++i) {
363  if ((flags & 1) && SDL_SubsystemRefCount[i] > 0) {
364  initialized |= (1 << i);
365  }
366 
367  flags >>= 1;
368  }
369 
370  return initialized;
371 }
372 
373 void
374 SDL_Quit(void)
375 {
377 
378  /* Quit all subsystems */
379 #if SDL_VIDEO_DRIVER_WINDOWS
380  SDL_HelperWindowDestroy();
381 #endif
383 
384 #if !SDL_TIMERS_DISABLED
385  SDL_TicksQuit();
386 #endif
387 
388  SDL_ClearHints();
391 
392  /* Now that every subsystem has been quit, we reset the subsystem refcount
393  * and the list of initialized subsystems.
394  */
396 
398 }
399 
400 /* Get the library version number */
401 void
403 {
404  SDL_VERSION(ver);
405 }
406 
407 /* Get the library source revision */
408 const char *
410 {
411  return SDL_REVISION;
412 }
413 
414 /* Get the library source revision number */
415 int
417 {
418  return SDL_REVISION_NUMBER;
419 }
420 
421 /* Get the name of the platform */
422 const char *
424 {
425 #if __AIX__
426  return "AIX";
427 #elif __ANDROID__
428  return "Android";
429 #elif __BSDI__
430  return "BSDI";
431 #elif __DREAMCAST__
432  return "Dreamcast";
433 #elif __EMSCRIPTEN__
434  return "Emscripten";
435 #elif __FREEBSD__
436  return "FreeBSD";
437 #elif __HAIKU__
438  return "Haiku";
439 #elif __HPUX__
440  return "HP-UX";
441 #elif __IRIX__
442  return "Irix";
443 #elif __LINUX__
444  return "Linux";
445 #elif __MINT__
446  return "Atari MiNT";
447 #elif __MACOS__
448  return "MacOS Classic";
449 #elif __MACOSX__
450  return "Mac OS X";
451 #elif __NACL__
452  return "NaCl";
453 #elif __NETBSD__
454  return "NetBSD";
455 #elif __OPENBSD__
456  return "OpenBSD";
457 #elif __OS2__
458  return "OS/2";
459 #elif __OSF__
460  return "OSF/1";
461 #elif __QNXNTO__
462  return "QNX Neutrino";
463 #elif __RISCOS__
464  return "RISC OS";
465 #elif __SOLARIS__
466  return "Solaris";
467 #elif __WIN32__
468  return "Windows";
469 #elif __WINRT__
470  return "WinRT";
471 #elif __TVOS__
472  return "tvOS";
473 #elif __IPHONEOS__
474  return "iOS";
475 #elif __PSP__
476  return "PlayStation Portable";
477 #else
478  return "Unknown (see SDL_platform.h)";
479 #endif
480 }
481 
482 SDL_bool
484 {
485 #if __ANDROID__
486  extern SDL_bool SDL_IsAndroidTablet(void);
487  return SDL_IsAndroidTablet();
488 #elif __IPHONEOS__
489  extern SDL_bool SDL_IsIPad(void);
490  return SDL_IsIPad();
491 #else
492  return SDL_FALSE;
493 #endif
494 }
495 
496 #if defined(__WIN32__)
497 
498 #if (!defined(HAVE_LIBC) || defined(__WATCOMC__)) && !defined(SDL_STATIC_LIB)
499 /* Need to include DllMain() on Watcom C for some reason.. */
500 
501 BOOL APIENTRY
502 _DllMainCRTStartup(HANDLE hModule,
503  DWORD ul_reason_for_call, LPVOID lpReserved)
504 {
505  switch (ul_reason_for_call) {
506  case DLL_PROCESS_ATTACH:
507  case DLL_THREAD_ATTACH:
508  case DLL_THREAD_DETACH:
509  case DLL_PROCESS_DETACH:
510  break;
511  }
512  return TRUE;
513 }
514 #endif /* Building DLL */
515 
516 #endif /* __WIN32__ */
517 
518 /* vi: set sts=4 ts=4 sw=4 expandtab: */
SDL_bool SDL_IsAndroidTablet(void)
#define SDL_INIT_SENSOR
Definition: SDL.h:84
#define SDL_ClearError
#define SDL_INIT_EVENTS
Definition: SDL.h:83
void SDL_TimerQuit(void)
Definition: SDL_timer.c:239
const char * SDL_GetRevision(void)
Get the code revision of SDL that is linked against your program.
Definition: SDL.c:409
#define SDL_min(x, y)
Definition: SDL_stdinc.h:406
static SDL_bool SDL_MainIsReady
Definition: SDL.c:52
void SDL_HapticQuit(void)
Definition: SDL_haptic.c:394
#define SDL_LogResetPriorities
#define SDL_INIT_JOYSTICK
Definition: SDL.h:80
#define SDL_AudioInit
static Uint8 SDL_SubsystemRefCount[32]
Definition: SDL.c:55
void SDL_QuitSubSystem(Uint32 flags)
Definition: SDL.c:259
int SDL_Init(Uint32 flags)
Definition: SDL.c:253
int SDL_JoystickInit(void)
Definition: SDL_joystick.c:114
#define APIENTRY
Definition: SDL_opengl.h:139
SDL_FORCE_INLINE int SDL_MostSignificantBitIndex32(Uint32 x)
Definition: SDL_bits.h:61
int SDL_TimerInit(void)
Definition: SDL_timer.c:207
void SDL_Quit(void)
Definition: SDL.c:374
#define SDL_ClearHints
static SDL_bool SDL_bInMainQuit
Definition: SDL.c:54
Uint32 SDL_WasInit(Uint32 flags)
Definition: SDL.c:343
#define SDL_AudioQuit
#define SDL_REVISION_NUMBER
Definition: SDL_revision.h:2
#define SDL_VERSION(x)
Macro to determine SDL version program was compiled against.
Definition: SDL_version.h:79
void SDL_AssertionsQuit(void)
Definition: SDL_assert.c:404
void SDL_GetVersion(SDL_version *ver)
Get the version of SDL that is linked against your program.
Definition: SDL.c:402
Information the version of SDL in use.
Definition: SDL_version.h:51
static void SDL_PrivateSubsystemRefCountIncr(Uint32 subsystem)
Definition: SDL.c:59
#define SDL_VideoInit
void SDL_GameControllerQuit(void)
uint8_t Uint8
Definition: SDL_stdinc.h:179
#define TRUE
Definition: edid-parse.c:33
#define SDL_INIT_EVERYTHING
Definition: SDL.h:86
int SDL_SensorInit(void)
Definition: SDL_sensor.c:69
return Display return Display Bool Bool int int int return Display XEvent Bool(*) XPointer return Display return Display Drawable _Xconst char unsigned int unsigned int return Display Pixmap Pixmap XColor XColor unsigned int unsigned int return Display _Xconst char char int char return Display Visual unsigned int int int char unsigned int unsigned int in i)
Definition: SDL_x11sym.h:50
#define SDL_assert(condition)
Definition: SDL_assert.h:169
const char * SDL_GetPlatform()
Gets the name of the platform.
Definition: SDL.c:423
#define NULL
Definition: begin_code.h:167
SDL_bool
Definition: SDL_stdinc.h:161
static SDL_bool SDL_PrivateShouldInitSubsystem(Uint32 subsystem)
Definition: SDL.c:78
#define SDL_SetError
GLbitfield flags
#define SDL_INIT_TIMER
Definition: SDL.h:77
#define SDL_INIT_AUDIO
Definition: SDL.h:78
void SDL_EventsQuit(void)
Definition: SDL_events.c:1016
static void SDL_PrivateSubsystemRefCountDecr(Uint32 subsystem)
Definition: SDL.c:68
#define SDL_REVISION
Definition: SDL_revision.h:1
uint32_t Uint32
Definition: SDL_stdinc.h:203
void SDL_TicksInit(void)
#define SDL_VideoQuit
void SDL_SensorQuit(void)
Definition: SDL_sensor.c:440
GLuint GLfloat x0
void SDL_TicksQuit(void)
static SDL_bool SDL_PrivateShouldQuitSubsystem(Uint32 subsystem)
Definition: SDL.c:87
#define SDL_arraysize(array)
Definition: SDL_stdinc.h:115
#define SDL_INIT_GAMECONTROLLER
Definition: SDL.h:82
void SDL_JoystickQuit(void)
Definition: SDL_joystick.c:697
#define SDL_INIT_HAPTIC
Definition: SDL.h:81
int SDL_InitSubSystem(Uint32 flags)
Definition: SDL.c:106
SDL_FORCE_INLINE SDL_bool SDL_HasExactlyOneBitSet32(Uint32 x)
Definition: SDL_bits.h:105
int SDL_GameControllerInit(void)
int SDL_HapticInit(void)
Definition: SDL_haptic.c:39
int SDL_GetRevisionNumber(void)
Get the revision number of SDL that is linked against your program.
Definition: SDL.c:416
SDL_bool SDL_IsTablet()
Return true if the current device is a tablet.
Definition: SDL.c:483
#define SDL_INIT_VIDEO
Definition: SDL.h:79
#define SDL_memset
void SDL_SetMainReady(void)
Definition: SDL.c:100
int SDL_EventsInit(void)
Definition: SDL_events.c:1002