SDL  2.0
SDL.c
Go to the documentation of this file.
1 /*
2  Simple DirectMedia Layer
3  Copyright (C) 1997-2018 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_StartEventLoop() < 0) {
143  return (-1);
144  }
145  SDL_QuitInit();
146  }
147  SDL_PrivateSubsystemRefCountIncr(SDL_INIT_EVENTS);
148 #else
149  return SDL_SetError("SDL not built with events support");
150 #endif
151  }
152 
153  /* Initialize the timer subsystem */
154  if ((flags & SDL_INIT_TIMER)){
155 #if !SDL_TIMERS_DISABLED
156  if (SDL_PrivateShouldInitSubsystem(SDL_INIT_TIMER)) {
157  if (SDL_TimerInit() < 0) {
158  return (-1);
159  }
160  }
161  SDL_PrivateSubsystemRefCountIncr(SDL_INIT_TIMER);
162 #else
163  return SDL_SetError("SDL not built with timer support");
164 #endif
165  }
166 
167  /* Initialize the video subsystem */
168  if ((flags & SDL_INIT_VIDEO)){
169 #if !SDL_VIDEO_DISABLED
170  if (SDL_PrivateShouldInitSubsystem(SDL_INIT_VIDEO)) {
171  if (SDL_VideoInit(NULL) < 0) {
172  return (-1);
173  }
174  }
175  SDL_PrivateSubsystemRefCountIncr(SDL_INIT_VIDEO);
176 #else
177  return SDL_SetError("SDL not built with video support");
178 #endif
179  }
180 
181  /* Initialize the audio subsystem */
182  if ((flags & SDL_INIT_AUDIO)){
183 #if !SDL_AUDIO_DISABLED
184  if (SDL_PrivateShouldInitSubsystem(SDL_INIT_AUDIO)) {
185  if (SDL_AudioInit(NULL) < 0) {
186  return (-1);
187  }
188  }
189  SDL_PrivateSubsystemRefCountIncr(SDL_INIT_AUDIO);
190 #else
191  return SDL_SetError("SDL not built with audio support");
192 #endif
193  }
194 
195  /* Initialize the joystick subsystem */
196  if ((flags & SDL_INIT_JOYSTICK)){
197 #if !SDL_JOYSTICK_DISABLED
198  if (SDL_PrivateShouldInitSubsystem(SDL_INIT_JOYSTICK)) {
199  if (SDL_JoystickInit() < 0) {
200  return (-1);
201  }
202  }
203  SDL_PrivateSubsystemRefCountIncr(SDL_INIT_JOYSTICK);
204 #else
205  return SDL_SetError("SDL not built with joystick support");
206 #endif
207  }
208 
209  if ((flags & SDL_INIT_GAMECONTROLLER)){
210 #if !SDL_JOYSTICK_DISABLED
211  if (SDL_PrivateShouldInitSubsystem(SDL_INIT_GAMECONTROLLER)) {
212  if (SDL_GameControllerInit() < 0) {
213  return (-1);
214  }
215  }
216  SDL_PrivateSubsystemRefCountIncr(SDL_INIT_GAMECONTROLLER);
217 #else
218  return SDL_SetError("SDL not built with joystick support");
219 #endif
220  }
221 
222  /* Initialize the haptic subsystem */
223  if ((flags & SDL_INIT_HAPTIC)){
224 #if !SDL_HAPTIC_DISABLED
225  if (SDL_PrivateShouldInitSubsystem(SDL_INIT_HAPTIC)) {
226  if (SDL_HapticInit() < 0) {
227  return (-1);
228  }
229  }
230  SDL_PrivateSubsystemRefCountIncr(SDL_INIT_HAPTIC);
231 #else
232  return SDL_SetError("SDL not built with haptic (force feedback) support");
233 #endif
234  }
235 
236  /* Initialize the sensor subsystem */
237  if ((flags & SDL_INIT_SENSOR)){
238 #if !SDL_SENSOR_DISABLED
239  if (SDL_PrivateShouldInitSubsystem(SDL_INIT_SENSOR)) {
240  if (SDL_SensorInit() < 0) {
241  return (-1);
242  }
243  }
244  SDL_PrivateSubsystemRefCountIncr(SDL_INIT_SENSOR);
245 #else
246  return SDL_SetError("SDL not built with sensor support");
247 #endif
248  }
249 
250  return (0);
251 }
252 
253 int
255 {
256  return SDL_InitSubSystem(flags);
257 }
258 
259 void
261 {
262  /* Shut down requested initialized subsystems */
263 #if !SDL_SENSOR_DISABLED
264  if ((flags & SDL_INIT_SENSOR)) {
265  if (SDL_PrivateShouldQuitSubsystem(SDL_INIT_SENSOR)) {
266  SDL_SensorQuit();
267  }
268  SDL_PrivateSubsystemRefCountDecr(SDL_INIT_SENSOR);
269  }
270 #endif
271 
272 #if !SDL_JOYSTICK_DISABLED
273  if ((flags & SDL_INIT_GAMECONTROLLER)) {
274  /* game controller implies joystick */
275  flags |= SDL_INIT_JOYSTICK;
276 
277  if (SDL_PrivateShouldQuitSubsystem(SDL_INIT_GAMECONTROLLER)) {
279  }
280  SDL_PrivateSubsystemRefCountDecr(SDL_INIT_GAMECONTROLLER);
281  }
282 
283  if ((flags & SDL_INIT_JOYSTICK)) {
284  /* joystick implies events */
285  flags |= SDL_INIT_EVENTS;
286 
287  if (SDL_PrivateShouldQuitSubsystem(SDL_INIT_JOYSTICK)) {
289  }
290  SDL_PrivateSubsystemRefCountDecr(SDL_INIT_JOYSTICK);
291  }
292 #endif
293 
294 #if !SDL_HAPTIC_DISABLED
295  if ((flags & SDL_INIT_HAPTIC)) {
296  if (SDL_PrivateShouldQuitSubsystem(SDL_INIT_HAPTIC)) {
297  SDL_HapticQuit();
298  }
299  SDL_PrivateSubsystemRefCountDecr(SDL_INIT_HAPTIC);
300  }
301 #endif
302 
303 #if !SDL_AUDIO_DISABLED
304  if ((flags & SDL_INIT_AUDIO)) {
305  if (SDL_PrivateShouldQuitSubsystem(SDL_INIT_AUDIO)) {
306  SDL_AudioQuit();
307  }
308  SDL_PrivateSubsystemRefCountDecr(SDL_INIT_AUDIO);
309  }
310 #endif
311 
312 #if !SDL_VIDEO_DISABLED
313  if ((flags & SDL_INIT_VIDEO)) {
314  /* video implies events */
315  flags |= SDL_INIT_EVENTS;
316 
317  if (SDL_PrivateShouldQuitSubsystem(SDL_INIT_VIDEO)) {
318  SDL_VideoQuit();
319  }
320  SDL_PrivateSubsystemRefCountDecr(SDL_INIT_VIDEO);
321  }
322 #endif
323 
324 #if !SDL_TIMERS_DISABLED
325  if ((flags & SDL_INIT_TIMER)) {
326  if (SDL_PrivateShouldQuitSubsystem(SDL_INIT_TIMER)) {
327  SDL_TimerQuit();
328  }
329  SDL_PrivateSubsystemRefCountDecr(SDL_INIT_TIMER);
330  }
331 #endif
332 
333 #if !SDL_EVENTS_DISABLED
334  if ((flags & SDL_INIT_EVENTS)) {
335  if (SDL_PrivateShouldQuitSubsystem(SDL_INIT_EVENTS)) {
336  SDL_QuitQuit();
338  }
339  SDL_PrivateSubsystemRefCountDecr(SDL_INIT_EVENTS);
340  }
341 #endif
342 }
343 
344 Uint32
346 {
347  int i;
348  int num_subsystems = SDL_arraysize(SDL_SubsystemRefCount);
349  Uint32 initialized = 0;
350 
351  if (!flags) {
352  flags = SDL_INIT_EVERYTHING;
353  }
354 
355  num_subsystems = SDL_min(num_subsystems, SDL_MostSignificantBitIndex32(flags) + 1);
356 
357  /* Iterate over each bit in flags, and check the matching subsystem. */
358  for (i = 0; i < num_subsystems; ++i) {
359  if ((flags & 1) && SDL_SubsystemRefCount[i] > 0) {
360  initialized |= (1 << i);
361  }
362 
363  flags >>= 1;
364  }
365 
366  return initialized;
367 }
368 
369 void
370 SDL_Quit(void)
371 {
373 
374  /* Quit all subsystems */
375 #if SDL_VIDEO_DRIVER_WINDOWS
376  SDL_HelperWindowDestroy();
377 #endif
379 
380 #if !SDL_TIMERS_DISABLED
381  SDL_TicksQuit();
382 #endif
383 
384  SDL_ClearHints();
387 
388  /* Now that every subsystem has been quit, we reset the subsystem refcount
389  * and the list of initialized subsystems.
390  */
392 
394 }
395 
396 /* Get the library version number */
397 void
399 {
400  SDL_VERSION(ver);
401 }
402 
403 /* Get the library source revision */
404 const char *
406 {
407  return SDL_REVISION;
408 }
409 
410 /* Get the library source revision number */
411 int
413 {
414  return SDL_REVISION_NUMBER;
415 }
416 
417 /* Get the name of the platform */
418 const char *
420 {
421 #if __AIX__
422  return "AIX";
423 #elif __ANDROID__
424  return "Android";
425 #elif __BSDI__
426  return "BSDI";
427 #elif __DREAMCAST__
428  return "Dreamcast";
429 #elif __EMSCRIPTEN__
430  return "Emscripten";
431 #elif __FREEBSD__
432  return "FreeBSD";
433 #elif __HAIKU__
434  return "Haiku";
435 #elif __HPUX__
436  return "HP-UX";
437 #elif __IRIX__
438  return "Irix";
439 #elif __LINUX__
440  return "Linux";
441 #elif __MINT__
442  return "Atari MiNT";
443 #elif __MACOS__
444  return "MacOS Classic";
445 #elif __MACOSX__
446  return "Mac OS X";
447 #elif __NACL__
448  return "NaCl";
449 #elif __NETBSD__
450  return "NetBSD";
451 #elif __OPENBSD__
452  return "OpenBSD";
453 #elif __OS2__
454  return "OS/2";
455 #elif __OSF__
456  return "OSF/1";
457 #elif __QNXNTO__
458  return "QNX Neutrino";
459 #elif __RISCOS__
460  return "RISC OS";
461 #elif __SOLARIS__
462  return "Solaris";
463 #elif __WIN32__
464  return "Windows";
465 #elif __WINRT__
466  return "WinRT";
467 #elif __TVOS__
468  return "tvOS";
469 #elif __IPHONEOS__
470  return "iOS";
471 #elif __PSP__
472  return "PlayStation Portable";
473 #else
474  return "Unknown (see SDL_platform.h)";
475 #endif
476 }
477 
478 SDL_bool
480 {
481 #if __ANDROID__
482  extern SDL_bool SDL_IsAndroidTablet(void);
483  return SDL_IsAndroidTablet();
484 #elif __IPHONEOS__
485  extern SDL_bool SDL_IsIPad(void);
486  return SDL_IsIPad();
487 #else
488  return SDL_FALSE;
489 #endif
490 }
491 
492 #if defined(__WIN32__)
493 
494 #if (!defined(HAVE_LIBC) || defined(__WATCOMC__)) && !defined(SDL_STATIC_LIB)
495 /* Need to include DllMain() on Watcom C for some reason.. */
496 
497 BOOL APIENTRY
498 _DllMainCRTStartup(HANDLE hModule,
499  DWORD ul_reason_for_call, LPVOID lpReserved)
500 {
501  switch (ul_reason_for_call) {
502  case DLL_PROCESS_ATTACH:
503  case DLL_THREAD_ATTACH:
504  case DLL_THREAD_DETACH:
505  case DLL_PROCESS_DETACH:
506  break;
507  }
508  return TRUE;
509 }
510 #endif /* Building DLL */
511 
512 #endif /* __WIN32__ */
513 
514 /* 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:405
#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:390
#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:260
int SDL_Init(Uint32 flags)
Definition: SDL.c:254
int SDL_JoystickInit(void)
Definition: SDL_joystick.c:114
#define APIENTRY
Definition: SDL_opengl.h:139
int SDL_StartEventLoop(void)
Definition: SDL_events.c:391
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:370
#define SDL_ClearHints
static SDL_bool SDL_bInMainQuit
Definition: SDL.c:54
Uint32 SDL_WasInit(Uint32 flags)
Definition: SDL.c:345
int SDL_QuitInit(void)
Definition: SDL_quit.c:92
#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
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
void SDL_AssertionsQuit(void)
Definition: SDL_assert.c:397
void SDL_GetVersion(SDL_version *ver)
Get the version of SDL that is linked against your program.
Definition: SDL.c:398
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
#define SDL_assert(condition)
Definition: SDL_assert.h:169
const char * SDL_GetPlatform()
Gets the name of the platform.
Definition: SDL.c:419
#define NULL
Definition: begin_code.h:164
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
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
int SDL_GameControllerInit(void)
int SDL_HapticInit(void)
Definition: SDL_haptic.c:35
int SDL_GetRevisionNumber(void)
Get the revision number of SDL that is linked against your program.
Definition: SDL.c:412
SDL_bool SDL_IsTablet()
Return true if the current device is a tablet.
Definition: SDL.c:479
#define SDL_INIT_VIDEO
Definition: SDL.h:79
#define SDL_memset
void SDL_SetMainReady(void)
Definition: SDL.c:100
void SDL_QuitQuit(void)
Definition: SDL_quit.c:128
void SDL_StopEventLoop(void)
Definition: SDL_events.c:317