SDL  2.0
SDL.c
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1 /*
2  Simple DirectMedia Layer
3  Copyright (C) 1997-2020 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 #elif defined(__OS2__)
26 #include <stdlib.h> /* For _exit() */
27 #elif !defined(__WINRT__)
28 #include <unistd.h> /* For _exit(), etc. */
29 #endif
30 
31 #if defined(__EMSCRIPTEN__)
32 #include <emscripten.h>
33 #endif
34 
35 /* Initialization code for SDL */
36 
37 #include "SDL.h"
38 #include "SDL_bits.h"
39 #include "SDL_revision.h"
40 #include "SDL_assert_c.h"
41 #include "events/SDL_events_c.h"
42 #include "haptic/SDL_haptic_c.h"
44 #include "sensor/SDL_sensor_c.h"
45 
46 /* Initialization/Cleanup routines */
47 #if !SDL_TIMERS_DISABLED
48 # include "timer/SDL_timer_c.h"
49 #endif
50 #if SDL_VIDEO_DRIVER_WINDOWS
51 extern int SDL_HelperWindowCreate(void);
52 extern int SDL_HelperWindowDestroy(void);
53 #endif
54 
55 
56 /* This is not declared in any header, although it is shared between some
57  parts of SDL, because we don't want anything calling it without an
58  extremely good reason. */
59 extern SDL_NORETURN void SDL_ExitProcess(int exitcode);
60 SDL_NORETURN void SDL_ExitProcess(int exitcode)
61 {
62 #ifdef __WIN32__
63  /* "if you do not know the state of all threads in your process, it is
64  better to call TerminateProcess than ExitProcess"
65  https://msdn.microsoft.com/en-us/library/windows/desktop/ms682658(v=vs.85).aspx */
66  TerminateProcess(GetCurrentProcess(), exitcode);
67  /* MingW doesn't have TerminateProcess marked as noreturn, so add an
68  ExitProcess here that will never be reached but make MingW happy. */
69  ExitProcess(exitcode);
70 #elif defined(__EMSCRIPTEN__)
71  emscripten_cancel_main_loop(); /* this should "kill" the app. */
72  emscripten_force_exit(exitcode); /* this should "kill" the app. */
73  exit(exitcode);
74 #elif defined(__HAIKU__) /* Haiku has _Exit, but it's not marked noreturn. */
75  _exit(exitcode);
76 #elif defined(HAVE__EXIT) /* Upper case _Exit() */
77  _Exit(exitcode);
78 #else
79  _exit(exitcode);
80 #endif
81 }
82 
83 
84 /* The initialized subsystems */
85 #ifdef SDL_MAIN_NEEDED
87 #else
89 #endif
92 
93 /* Private helper to increment a subsystem's ref counter. */
94 static void
96 {
97  int subsystem_index = SDL_MostSignificantBitIndex32(subsystem);
98  SDL_assert(SDL_SubsystemRefCount[subsystem_index] < 255);
99  ++SDL_SubsystemRefCount[subsystem_index];
100 }
101 
102 /* Private helper to decrement a subsystem's ref counter. */
103 static void
105 {
106  int subsystem_index = SDL_MostSignificantBitIndex32(subsystem);
107  if (SDL_SubsystemRefCount[subsystem_index] > 0) {
108  --SDL_SubsystemRefCount[subsystem_index];
109  }
110 }
111 
112 /* Private helper to check if a system needs init. */
113 static SDL_bool
115 {
116  int subsystem_index = SDL_MostSignificantBitIndex32(subsystem);
117  SDL_assert(SDL_SubsystemRefCount[subsystem_index] < 255);
118  return (SDL_SubsystemRefCount[subsystem_index] == 0) ? SDL_TRUE : SDL_FALSE;
119 }
120 
121 /* Private helper to check if a system needs to be quit. */
122 static SDL_bool
124  int subsystem_index = SDL_MostSignificantBitIndex32(subsystem);
125  if (SDL_SubsystemRefCount[subsystem_index] == 0) {
126  return SDL_FALSE;
127  }
128 
129  /* If we're in SDL_Quit, we shut down every subsystem, even if refcount
130  * isn't zero.
131  */
132  return (SDL_SubsystemRefCount[subsystem_index] == 1 || SDL_bInMainQuit) ? SDL_TRUE : SDL_FALSE;
133 }
134 
135 void
137 {
139 }
140 
141 int
143 {
144  if (!SDL_MainIsReady) {
145  SDL_SetError("Application didn't initialize properly, did you include SDL_main.h in the file containing your main() function?");
146  return -1;
147  }
148 
149  /* Clear the error message */
150  SDL_ClearError();
151 
152  if ((flags & SDL_INIT_GAMECONTROLLER)) {
153  /* game controller implies joystick */
155  }
156 
158  /* video or joystick implies events */
160  }
161 
162 #if SDL_VIDEO_DRIVER_WINDOWS
164  if (SDL_HelperWindowCreate() < 0) {
165  return -1;
166  }
167  }
168 #endif
169 
170 #if !SDL_TIMERS_DISABLED
171  SDL_TicksInit();
172 #endif
173 
174  /* Initialize the event subsystem */
175  if ((flags & SDL_INIT_EVENTS)) {
176 #if !SDL_EVENTS_DISABLED
178  if (SDL_EventsInit() < 0) {
179  return (-1);
180  }
181  }
183 #else
184  return SDL_SetError("SDL not built with events support");
185 #endif
186  }
187 
188  /* Initialize the timer subsystem */
189  if ((flags & SDL_INIT_TIMER)){
190 #if !SDL_TIMERS_DISABLED
192  if (SDL_TimerInit() < 0) {
193  return (-1);
194  }
195  }
197 #else
198  return SDL_SetError("SDL not built with timer support");
199 #endif
200  }
201 
202  /* Initialize the video subsystem */
203  if ((flags & SDL_INIT_VIDEO)){
204 #if !SDL_VIDEO_DISABLED
206  if (SDL_VideoInit(NULL) < 0) {
207  return (-1);
208  }
209  }
211 #else
212  return SDL_SetError("SDL not built with video support");
213 #endif
214  }
215 
216  /* Initialize the audio subsystem */
217  if ((flags & SDL_INIT_AUDIO)){
218 #if !SDL_AUDIO_DISABLED
220  if (SDL_AudioInit(NULL) < 0) {
221  return (-1);
222  }
223  }
225 #else
226  return SDL_SetError("SDL not built with audio support");
227 #endif
228  }
229 
230  /* Initialize the joystick subsystem */
231  if ((flags & SDL_INIT_JOYSTICK)){
232 #if !SDL_JOYSTICK_DISABLED
234  if (SDL_JoystickInit() < 0) {
235  return (-1);
236  }
237  }
239 #else
240  return SDL_SetError("SDL not built with joystick support");
241 #endif
242  }
243 
245 #if !SDL_JOYSTICK_DISABLED
247  if (SDL_GameControllerInit() < 0) {
248  return (-1);
249  }
250  }
252 #else
253  return SDL_SetError("SDL not built with joystick support");
254 #endif
255  }
256 
257  /* Initialize the haptic subsystem */
258  if ((flags & SDL_INIT_HAPTIC)){
259 #if !SDL_HAPTIC_DISABLED
261  if (SDL_HapticInit() < 0) {
262  return (-1);
263  }
264  }
266 #else
267  return SDL_SetError("SDL not built with haptic (force feedback) support");
268 #endif
269  }
270 
271  /* Initialize the sensor subsystem */
272  if ((flags & SDL_INIT_SENSOR)){
273 #if !SDL_SENSOR_DISABLED
275  if (SDL_SensorInit() < 0) {
276  return (-1);
277  }
278  }
280 #else
281  return SDL_SetError("SDL not built with sensor support");
282 #endif
283  }
284 
285  return (0);
286 }
287 
288 int
290 {
291  return SDL_InitSubSystem(flags);
292 }
293 
294 void
296 {
297  /* Shut down requested initialized subsystems */
298 #if !SDL_SENSOR_DISABLED
299  if ((flags & SDL_INIT_SENSOR)) {
301  SDL_SensorQuit();
302  }
304  }
305 #endif
306 
307 #if !SDL_JOYSTICK_DISABLED
308  if ((flags & SDL_INIT_GAMECONTROLLER)) {
309  /* game controller implies joystick */
311 
314  }
316  }
317 
318  if ((flags & SDL_INIT_JOYSTICK)) {
319  /* joystick implies events */
321 
324  }
326  }
327 #endif
328 
329 #if !SDL_HAPTIC_DISABLED
330  if ((flags & SDL_INIT_HAPTIC)) {
332  SDL_HapticQuit();
333  }
335  }
336 #endif
337 
338 #if !SDL_AUDIO_DISABLED
339  if ((flags & SDL_INIT_AUDIO)) {
341  SDL_AudioQuit();
342  }
344  }
345 #endif
346 
347 #if !SDL_VIDEO_DISABLED
348  if ((flags & SDL_INIT_VIDEO)) {
349  /* video implies events */
351 
353  SDL_VideoQuit();
354  }
356  }
357 #endif
358 
359 #if !SDL_TIMERS_DISABLED
360  if ((flags & SDL_INIT_TIMER)) {
362  SDL_TimerQuit();
363  }
365  }
366 #endif
367 
368 #if !SDL_EVENTS_DISABLED
369  if ((flags & SDL_INIT_EVENTS)) {
371  SDL_EventsQuit();
372  }
374  }
375 #endif
376 }
377 
378 Uint32
380 {
381  int i;
382  int num_subsystems = SDL_arraysize(SDL_SubsystemRefCount);
383  Uint32 initialized = 0;
384 
385  /* Fast path for checking one flag */
387  int subsystem_index = SDL_MostSignificantBitIndex32(flags);
388  return SDL_SubsystemRefCount[subsystem_index] ? flags : 0;
389  }
390 
391  if (!flags) {
393  }
394 
395  num_subsystems = SDL_min(num_subsystems, SDL_MostSignificantBitIndex32(flags) + 1);
396 
397  /* Iterate over each bit in flags, and check the matching subsystem. */
398  for (i = 0; i < num_subsystems; ++i) {
399  if ((flags & 1) && SDL_SubsystemRefCount[i] > 0) {
400  initialized |= (1 << i);
401  }
402 
403  flags >>= 1;
404  }
405 
406  return initialized;
407 }
408 
409 void
410 SDL_Quit(void)
411 {
413 
414  /* Quit all subsystems */
415 #if SDL_VIDEO_DRIVER_WINDOWS
416  SDL_HelperWindowDestroy();
417 #endif
419 
420 #if !SDL_TIMERS_DISABLED
421  SDL_TicksQuit();
422 #endif
423 
424  SDL_ClearHints();
427 
428  /* Now that every subsystem has been quit, we reset the subsystem refcount
429  * and the list of initialized subsystems.
430  */
432 
434 }
435 
436 /* Get the library version number */
437 void
439 {
440  SDL_VERSION(ver);
441 }
442 
443 /* Get the library source revision */
444 const char *
446 {
447  return SDL_REVISION;
448 }
449 
450 /* Get the library source revision number */
451 int
453 {
454  return SDL_REVISION_NUMBER;
455 }
456 
457 /* Get the name of the platform */
458 const char *
460 {
461 #if __AIX__
462  return "AIX";
463 #elif __ANDROID__
464  return "Android";
465 #elif __BSDI__
466  return "BSDI";
467 #elif __DREAMCAST__
468  return "Dreamcast";
469 #elif __EMSCRIPTEN__
470  return "Emscripten";
471 #elif __FREEBSD__
472  return "FreeBSD";
473 #elif __HAIKU__
474  return "Haiku";
475 #elif __HPUX__
476  return "HP-UX";
477 #elif __IRIX__
478  return "Irix";
479 #elif __LINUX__
480  return "Linux";
481 #elif __MINT__
482  return "Atari MiNT";
483 #elif __MACOS__
484  return "MacOS Classic";
485 #elif __MACOSX__
486  return "Mac OS X";
487 #elif __NACL__
488  return "NaCl";
489 #elif __NETBSD__
490  return "NetBSD";
491 #elif __OPENBSD__
492  return "OpenBSD";
493 #elif __OS2__
494  return "OS/2";
495 #elif __OSF__
496  return "OSF/1";
497 #elif __QNXNTO__
498  return "QNX Neutrino";
499 #elif __RISCOS__
500  return "RISC OS";
501 #elif __SOLARIS__
502  return "Solaris";
503 #elif __WIN32__
504  return "Windows";
505 #elif __WINRT__
506  return "WinRT";
507 #elif __TVOS__
508  return "tvOS";
509 #elif __IPHONEOS__
510  return "iOS";
511 #elif __PSP__
512  return "PlayStation Portable";
513 #else
514  return "Unknown (see SDL_platform.h)";
515 #endif
516 }
517 
518 SDL_bool
520 {
521 #if __ANDROID__
522  extern SDL_bool SDL_IsAndroidTablet(void);
523  return SDL_IsAndroidTablet();
524 #elif __IPHONEOS__
525  extern SDL_bool SDL_IsIPad(void);
526  return SDL_IsIPad();
527 #else
528  return SDL_FALSE;
529 #endif
530 }
531 
532 #if defined(__WIN32__)
533 
534 #if (!defined(HAVE_LIBC) || defined(__WATCOMC__)) && !defined(SDL_STATIC_LIB)
535 /* Need to include DllMain() on Watcom C for some reason.. */
536 
537 BOOL APIENTRY
538 _DllMainCRTStartup(HANDLE hModule,
539  DWORD ul_reason_for_call, LPVOID lpReserved)
540 {
541  switch (ul_reason_for_call) {
542  case DLL_PROCESS_ATTACH:
543  case DLL_THREAD_ATTACH:
544  case DLL_THREAD_DETACH:
545  case DLL_PROCESS_DETACH:
546  break;
547  }
548  return TRUE;
549 }
550 #endif /* Building DLL */
551 
552 #endif /* __WIN32__ */
553 
554 /* vi: set sts=4 ts=4 sw=4 expandtab: */
SDL.h
SDL_memset
#define SDL_memset
Definition: SDL_dynapi_overrides.h:386
SDL_GetRevision
const char * SDL_GetRevision(void)
Get the code revision of SDL that is linked against your program.
Definition: SDL.c:445
Uint32
uint32_t Uint32
Definition: SDL_stdinc.h:203
SDL_GetPlatform
const char * SDL_GetPlatform()
Gets the name of the platform.
Definition: SDL.c:459
SDL_GetRevisionNumber
int SDL_GetRevisionNumber(void)
Get the revision number of SDL that is linked against your program.
Definition: SDL.c:452
SDL_AudioInit
#define SDL_AudioInit
Definition: SDL_dynapi_overrides.h:75
SDL_PrivateShouldInitSubsystem
static SDL_bool SDL_PrivateShouldInitSubsystem(Uint32 subsystem)
Definition: SDL.c:114
SDL_TimerQuit
void SDL_TimerQuit(void)
Definition: SDL_timer.c:239
SDL_ClearError
#define SDL_ClearError
Definition: SDL_dynapi_overrides.h:114
SDL_HapticQuit
void SDL_HapticQuit(void)
Definition: SDL_haptic.c:394
SDL_PrivateSubsystemRefCountIncr
static void SDL_PrivateSubsystemRefCountIncr(Uint32 subsystem)
Definition: SDL.c:95
SDL_joystick_c.h
NULL
#define NULL
Definition: begin_code.h:167
SDL_JoystickInit
int SDL_JoystickInit(void)
Definition: SDL_joystick.c:201
SDL_SubsystemRefCount
static Uint8 SDL_SubsystemRefCount[32]
Definition: SDL.c:91
SDL_version
Information the version of SDL in use.
Definition: SDL_version.h:51
TRUE
#define TRUE
Definition: edid-parse.c:33
SDL_LogResetPriorities
#define SDL_LogResetPriorities
Definition: SDL_dynapi_overrides.h:238
SDL_INIT_JOYSTICK
#define SDL_INIT_JOYSTICK
Definition: SDL.h:81
SDL_VERSION
#define SDL_VERSION(x)
Macro to determine SDL version program was compiled against.
Definition: SDL_version.h:79
SDL_IsAndroidTablet
SDL_bool SDL_IsAndroidTablet(void)
SDL_INIT_EVENTS
#define SDL_INIT_EVENTS
Definition: SDL.h:84
SDL_TimerInit
int SDL_TimerInit(void)
Definition: SDL_timer.c:207
SDL_TicksInit
void SDL_TicksInit(void)
SDL_SensorInit
int SDL_SensorInit(void)
Definition: SDL_sensor.c:69
SDL_revision.h
x0
GLuint GLfloat x0
Definition: SDL_opengl_glext.h:8586
SDL_ClearHints
#define SDL_ClearHints
Definition: SDL_dynapi_overrides.h:194
SDL_assert_c.h
SDL_AudioQuit
#define SDL_AudioQuit
Definition: SDL_dynapi_overrides.h:76
SDL_bits.h
SDL_GameControllerInit
int SDL_GameControllerInit(void)
Definition: SDL_gamecontroller.c:1399
SDL_SensorQuit
void SDL_SensorQuit(void)
Definition: SDL_sensor.c:440
SDL_INIT_SENSOR
#define SDL_INIT_SENSOR
Definition: SDL.h:85
SDL_FALSE
@ SDL_FALSE
Definition: SDL_stdinc.h:163
SDL_PrivateSubsystemRefCountDecr
static void SDL_PrivateSubsystemRefCountDecr(Uint32 subsystem)
Definition: SDL.c:104
SDL_GetVersion
void SDL_GetVersion(SDL_version *ver)
Get the version of SDL that is linked against your program.
Definition: SDL.c:438
SDL_bInMainQuit
static SDL_bool SDL_bInMainQuit
Definition: SDL.c:90
SDL_internal.h
SDL_TicksQuit
void SDL_TicksQuit(void)
SDL_HapticInit
int SDL_HapticInit(void)
Definition: SDL_haptic.c:39
SDL_HasExactlyOneBitSet32
SDL_FORCE_INLINE SDL_bool SDL_HasExactlyOneBitSet32(Uint32 x)
Definition: SDL_bits.h:105
SDL_REVISION_NUMBER
#define SDL_REVISION_NUMBER
Definition: SDL_revision.h:2
SDL_JoystickQuit
void SDL_JoystickQuit(void)
Definition: SDL_joystick.c:858
SDL_VideoInit
#define SDL_VideoInit
Definition: SDL_dynapi_overrides.h:498
SDL_min
#define SDL_min(x, y)
Definition: SDL_stdinc.h:406
SDL_PrivateShouldQuitSubsystem
static SDL_bool SDL_PrivateShouldQuitSubsystem(Uint32 subsystem)
Definition: SDL.c:123
SDL_AssertionsQuit
void SDL_AssertionsQuit(void)
Definition: SDL_assert.c:385
SDL_WasInit
Uint32 SDL_WasInit(Uint32 flags)
Definition: SDL.c:379
SDL_ExitProcess
SDL_NORETURN void SDL_ExitProcess(int exitcode)
Definition: SDL.c:60
SDL_assert
#define SDL_assert(condition)
Definition: SDL_assert.h:169
SDL_INIT_HAPTIC
#define SDL_INIT_HAPTIC
Definition: SDL.h:82
APIENTRY
#define APIENTRY
Definition: SDL_opengl.h:139
SDL_Quit
void SDL_Quit(void)
Definition: SDL.c:410
SDL_IsTablet
SDL_bool SDL_IsTablet()
Return true if the current device is a tablet.
Definition: SDL.c:519
SDL_arraysize
#define SDL_arraysize(array)
Definition: SDL_stdinc.h:115
SDL_INIT_VIDEO
#define SDL_INIT_VIDEO
Definition: SDL.h:80
SDL_TRUE
@ SDL_TRUE
Definition: SDL_stdinc.h:164
SDL_haptic_c.h
SDL_REVISION
#define SDL_REVISION
Definition: SDL_revision.h:1
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#define SDL_INIT_TIMER
Definition: SDL.h:78
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#define SDL_SetError
Definition: SDL_dynapi_overrides.h:30
SDL_InitSubSystem
int SDL_InitSubSystem(Uint32 flags)
Definition: SDL.c:142
SDL_NORETURN
#define SDL_NORETURN
Definition: begin_code.h:157
SDL_GameControllerQuit
void SDL_GameControllerQuit(void)
Definition: SDL_gamecontroller.c:1994
SDL_events_c.h
SDL_SetMainReady
void SDL_SetMainReady(void)
Definition: SDL.c:136
SDL_VideoQuit
#define SDL_VideoQuit
Definition: SDL_dynapi_overrides.h:499
SDL_MostSignificantBitIndex32
SDL_FORCE_INLINE int SDL_MostSignificantBitIndex32(Uint32 x)
Definition: SDL_bits.h:61
SDL_windows.h
SDL_sensor_c.h
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#define SDL_INIT_GAMECONTROLLER
Definition: SDL.h:83
SDL_EventsInit
int SDL_EventsInit(void)
Definition: SDL_events.c:1009
SDL_EventsQuit
void SDL_EventsQuit(void)
Definition: SDL_events.c:1023
flags
GLbitfield flags
Definition: SDL_opengl_glext.h:1483
SDL_INIT_EVERYTHING
#define SDL_INIT_EVERYTHING
Definition: SDL.h:87
SDL_QuitSubSystem
void SDL_QuitSubSystem(Uint32 flags)
Definition: SDL.c:295
SDL_Init
int SDL_Init(Uint32 flags)
Definition: SDL.c:289
SDL_MainIsReady
static SDL_bool SDL_MainIsReady
Definition: SDL.c:88
SDL_timer_c.h
i
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
SDL_bool
SDL_bool
Definition: SDL_stdinc.h:161
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#define SDL_INIT_AUDIO
Definition: SDL.h:79
Uint8
uint8_t Uint8
Definition: SDL_stdinc.h:179