SDL  2.0
SDL.c
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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 
37 /* Initialization/Cleanup routines */
38 #if !SDL_TIMERS_DISABLED
39 # include "timer/SDL_timer_c.h"
40 #endif
41 #if SDL_VIDEO_DRIVER_WINDOWS
42 extern int SDL_HelperWindowCreate(void);
43 extern int SDL_HelperWindowDestroy(void);
44 #endif
45 
46 
47 /* The initialized subsystems */
48 #ifdef SDL_MAIN_NEEDED
50 #else
52 #endif
55 
56 /* Private helper to increment a subsystem's ref counter. */
57 static void
59 {
60  int subsystem_index = SDL_MostSignificantBitIndex32(subsystem);
61  SDL_assert(SDL_SubsystemRefCount[subsystem_index] < 255);
62  ++SDL_SubsystemRefCount[subsystem_index];
63 }
64 
65 /* Private helper to decrement a subsystem's ref counter. */
66 static void
68 {
69  int subsystem_index = SDL_MostSignificantBitIndex32(subsystem);
70  if (SDL_SubsystemRefCount[subsystem_index] > 0) {
71  --SDL_SubsystemRefCount[subsystem_index];
72  }
73 }
74 
75 /* Private helper to check if a system needs init. */
76 static SDL_bool
78 {
79  int subsystem_index = SDL_MostSignificantBitIndex32(subsystem);
80  SDL_assert(SDL_SubsystemRefCount[subsystem_index] < 255);
81  return (SDL_SubsystemRefCount[subsystem_index] == 0) ? SDL_TRUE : SDL_FALSE;
82 }
83 
84 /* Private helper to check if a system needs to be quit. */
85 static SDL_bool
87  int subsystem_index = SDL_MostSignificantBitIndex32(subsystem);
88  if (SDL_SubsystemRefCount[subsystem_index] == 0) {
89  return SDL_FALSE;
90  }
91 
92  /* If we're in SDL_Quit, we shut down every subsystem, even if refcount
93  * isn't zero.
94  */
95  return (SDL_SubsystemRefCount[subsystem_index] == 1 || SDL_bInMainQuit) ? SDL_TRUE : SDL_FALSE;
96 }
97 
98 void
100 {
102 }
103 
104 int
106 {
107  if (!SDL_MainIsReady) {
108  SDL_SetError("Application didn't initialize properly, did you include SDL_main.h in the file containing your main() function?");
109  return -1;
110  }
111 
112  /* Clear the error message */
113  SDL_ClearError();
114 
115  if ((flags & SDL_INIT_GAMECONTROLLER)) {
116  /* game controller implies joystick */
117  flags |= SDL_INIT_JOYSTICK;
118  }
119 
120  if ((flags & (SDL_INIT_VIDEO|SDL_INIT_JOYSTICK))) {
121  /* video or joystick implies events */
122  flags |= SDL_INIT_EVENTS;
123  }
124 
125 #if SDL_VIDEO_DRIVER_WINDOWS
126  if ((flags & (SDL_INIT_HAPTIC|SDL_INIT_JOYSTICK))) {
127  if (SDL_HelperWindowCreate() < 0) {
128  return -1;
129  }
130  }
131 #endif
132 
133 #if !SDL_TIMERS_DISABLED
134  SDL_TicksInit();
135 #endif
136 
137  /* Initialize the event subsystem */
138  if ((flags & SDL_INIT_EVENTS)) {
139 #if !SDL_EVENTS_DISABLED
140  if (SDL_PrivateShouldInitSubsystem(SDL_INIT_EVENTS)) {
141  if (SDL_StartEventLoop() < 0) {
142  return (-1);
143  }
144  SDL_QuitInit();
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  return (0);
236 }
237 
238 int
240 {
241  return SDL_InitSubSystem(flags);
242 }
243 
244 void
246 {
247  /* Shut down requested initialized subsystems */
248 #if !SDL_JOYSTICK_DISABLED
249  if ((flags & SDL_INIT_GAMECONTROLLER)) {
250  /* game controller implies joystick */
251  flags |= SDL_INIT_JOYSTICK;
252 
253  if (SDL_PrivateShouldQuitSubsystem(SDL_INIT_GAMECONTROLLER)) {
255  }
256  SDL_PrivateSubsystemRefCountDecr(SDL_INIT_GAMECONTROLLER);
257  }
258 
259  if ((flags & SDL_INIT_JOYSTICK)) {
260  /* joystick implies events */
261  flags |= SDL_INIT_EVENTS;
262 
263  if (SDL_PrivateShouldQuitSubsystem(SDL_INIT_JOYSTICK)) {
265  }
266  SDL_PrivateSubsystemRefCountDecr(SDL_INIT_JOYSTICK);
267  }
268 #endif
269 
270 #if !SDL_HAPTIC_DISABLED
271  if ((flags & SDL_INIT_HAPTIC)) {
272  if (SDL_PrivateShouldQuitSubsystem(SDL_INIT_HAPTIC)) {
273  SDL_HapticQuit();
274  }
275  SDL_PrivateSubsystemRefCountDecr(SDL_INIT_HAPTIC);
276  }
277 #endif
278 
279 #if !SDL_AUDIO_DISABLED
280  if ((flags & SDL_INIT_AUDIO)) {
281  if (SDL_PrivateShouldQuitSubsystem(SDL_INIT_AUDIO)) {
282  SDL_AudioQuit();
283  }
284  SDL_PrivateSubsystemRefCountDecr(SDL_INIT_AUDIO);
285  }
286 #endif
287 
288 #if !SDL_VIDEO_DISABLED
289  if ((flags & SDL_INIT_VIDEO)) {
290  /* video implies events */
291  flags |= SDL_INIT_EVENTS;
292 
293  if (SDL_PrivateShouldQuitSubsystem(SDL_INIT_VIDEO)) {
294  SDL_VideoQuit();
295  }
296  SDL_PrivateSubsystemRefCountDecr(SDL_INIT_VIDEO);
297  }
298 #endif
299 
300 #if !SDL_TIMERS_DISABLED
301  if ((flags & SDL_INIT_TIMER)) {
302  if (SDL_PrivateShouldQuitSubsystem(SDL_INIT_TIMER)) {
303  SDL_TimerQuit();
304  }
305  SDL_PrivateSubsystemRefCountDecr(SDL_INIT_TIMER);
306  }
307 #endif
308 
309 #if !SDL_EVENTS_DISABLED
310  if ((flags & SDL_INIT_EVENTS)) {
311  if (SDL_PrivateShouldQuitSubsystem(SDL_INIT_EVENTS)) {
312  SDL_QuitQuit();
314  }
315  SDL_PrivateSubsystemRefCountDecr(SDL_INIT_EVENTS);
316  }
317 #endif
318 }
319 
320 Uint32
322 {
323  int i;
324  int num_subsystems = SDL_arraysize(SDL_SubsystemRefCount);
325  Uint32 initialized = 0;
326 
327  if (!flags) {
328  flags = SDL_INIT_EVERYTHING;
329  }
330 
331  num_subsystems = SDL_min(num_subsystems, SDL_MostSignificantBitIndex32(flags) + 1);
332 
333  /* Iterate over each bit in flags, and check the matching subsystem. */
334  for (i = 0; i < num_subsystems; ++i) {
335  if ((flags & 1) && SDL_SubsystemRefCount[i] > 0) {
336  initialized |= (1 << i);
337  }
338 
339  flags >>= 1;
340  }
341 
342  return initialized;
343 }
344 
345 void
346 SDL_Quit(void)
347 {
349 
350  /* Quit all subsystems */
351 #if SDL_VIDEO_DRIVER_WINDOWS
352  SDL_HelperWindowDestroy();
353 #endif
355 
356 #if !SDL_TIMERS_DISABLED
357  SDL_TicksQuit();
358 #endif
359 
360  SDL_ClearHints();
363 
364  /* Now that every subsystem has been quit, we reset the subsystem refcount
365  * and the list of initialized subsystems.
366  */
368 
370 }
371 
372 /* Get the library version number */
373 void
375 {
376  SDL_VERSION(ver);
377 }
378 
379 /* Get the library source revision */
380 const char *
382 {
383  return SDL_REVISION;
384 }
385 
386 /* Get the library source revision number */
387 int
389 {
390  return SDL_REVISION_NUMBER;
391 }
392 
393 /* Get the name of the platform */
394 const char *
396 {
397 #if __AIX__
398  return "AIX";
399 #elif __ANDROID__
400  return "Android";
401 #elif __BSDI__
402  return "BSDI";
403 #elif __DREAMCAST__
404  return "Dreamcast";
405 #elif __EMSCRIPTEN__
406  return "Emscripten";
407 #elif __FREEBSD__
408  return "FreeBSD";
409 #elif __HAIKU__
410  return "Haiku";
411 #elif __HPUX__
412  return "HP-UX";
413 #elif __IRIX__
414  return "Irix";
415 #elif __LINUX__
416  return "Linux";
417 #elif __MINT__
418  return "Atari MiNT";
419 #elif __MACOS__
420  return "MacOS Classic";
421 #elif __MACOSX__
422  return "Mac OS X";
423 #elif __NACL__
424  return "NaCl";
425 #elif __NETBSD__
426  return "NetBSD";
427 #elif __OPENBSD__
428  return "OpenBSD";
429 #elif __OS2__
430  return "OS/2";
431 #elif __OSF__
432  return "OSF/1";
433 #elif __QNXNTO__
434  return "QNX Neutrino";
435 #elif __RISCOS__
436  return "RISC OS";
437 #elif __SOLARIS__
438  return "Solaris";
439 #elif __WIN32__
440  return "Windows";
441 #elif __WINRT__
442  return "WinRT";
443 #elif __TVOS__
444  return "tvOS";
445 #elif __IPHONEOS__
446  return "iOS";
447 #elif __PSP__
448  return "PlayStation Portable";
449 #else
450  return "Unknown (see SDL_platform.h)";
451 #endif
452 }
453 
454 #if defined(__WIN32__)
455 
456 #if (!defined(HAVE_LIBC) || defined(__WATCOMC__)) && !defined(SDL_STATIC_LIB)
457 /* Need to include DllMain() on Watcom C for some reason.. */
458 
459 BOOL APIENTRY
460 _DllMainCRTStartup(HANDLE hModule,
461  DWORD ul_reason_for_call, LPVOID lpReserved)
462 {
463  switch (ul_reason_for_call) {
464  case DLL_PROCESS_ATTACH:
465  case DLL_THREAD_ATTACH:
466  case DLL_THREAD_DETACH:
467  case DLL_PROCESS_DETACH:
468  break;
469  }
470  return TRUE;
471 }
472 #endif /* Building DLL */
473 
474 #endif /* __WIN32__ */
475 
476 /* vi: set sts=4 ts=4 sw=4 expandtab: */
#define SDL_ClearError
#define SDL_INIT_EVENTS
Definition: SDL.h:82
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:381
#define SDL_min(x, y)
Definition: SDL_stdinc.h:406
static SDL_bool SDL_MainIsReady
Definition: SDL.c:51
void SDL_HapticQuit(void)
Definition: SDL_haptic.c:390
#define SDL_LogResetPriorities
#define SDL_INIT_JOYSTICK
Definition: SDL.h:79
#define SDL_AudioInit
static Uint8 SDL_SubsystemRefCount[32]
Definition: SDL.c:54
void SDL_QuitSubSystem(Uint32 flags)
Definition: SDL.c:245
int SDL_Init(Uint32 flags)
Definition: SDL.c:239
int SDL_JoystickInit(void)
Definition: SDL_joystick.c:70
#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
uint32_t Uint32
Definition: SDL_stdinc.h:181
void SDL_Quit(void)
Definition: SDL.c:346
#define SDL_ClearHints
static SDL_bool SDL_bInMainQuit
Definition: SDL.c:53
Uint32 SDL_WasInit(Uint32 flags)
Definition: SDL.c:321
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
void SDL_AssertionsQuit(void)
Definition: SDL_assert.c:387
void SDL_GetVersion(SDL_version *ver)
Get the version of SDL that is linked against your program.
Definition: SDL.c:374
Information the version of SDL in use.
Definition: SDL_version.h:51
static void SDL_PrivateSubsystemRefCountIncr(Uint32 subsystem)
Definition: SDL.c:58
#define SDL_VideoInit
void SDL_GameControllerQuit(void)
uint8_t Uint8
Definition: SDL_stdinc.h:157
#define TRUE
Definition: edid-parse.c:33
#define SDL_INIT_EVERYTHING
Definition: SDL.h:84
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:395
#define NULL
Definition: begin_code.h:164
SDL_bool
Definition: SDL_stdinc.h:139
static SDL_bool SDL_PrivateShouldInitSubsystem(Uint32 subsystem)
Definition: SDL.c:77
#define SDL_SetError
GLbitfield flags
#define SDL_INIT_TIMER
Definition: SDL.h:76
#define SDL_INIT_AUDIO
Definition: SDL.h:77
static void SDL_PrivateSubsystemRefCountDecr(Uint32 subsystem)
Definition: SDL.c:67
#define SDL_REVISION
Definition: SDL_revision.h:1
void SDL_TicksInit(void)
#define SDL_VideoQuit
GLuint GLfloat x0
void SDL_TicksQuit(void)
static SDL_bool SDL_PrivateShouldQuitSubsystem(Uint32 subsystem)
Definition: SDL.c:86
#define SDL_arraysize(array)
Definition: SDL_stdinc.h:93
#define SDL_INIT_GAMECONTROLLER
Definition: SDL.h:81
void SDL_JoystickQuit(void)
Definition: SDL_joystick.c:545
#define SDL_INIT_HAPTIC
Definition: SDL.h:80
int SDL_InitSubSystem(Uint32 flags)
Definition: SDL.c:105
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:388
#define SDL_INIT_VIDEO
Definition: SDL.h:78
#define SDL_memset
void SDL_SetMainReady(void)
Definition: SDL.c:99
void SDL_QuitQuit(void)
Definition: SDL_quit.c:128
void SDL_StopEventLoop(void)
Definition: SDL_events.c:317