SDL  2.0
SDL_main.h
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1 /*
2  Simple DirectMedia Layer
3  Copyright (C) 1997-2022 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 
22 #ifndef SDL_main_h_
23 #define SDL_main_h_
24 
25 #include "SDL_stdinc.h"
26 
27 /**
28  * \file SDL_main.h
29  *
30  * Redefine main() on some platforms so that it is called by SDL.
31  */
32 
33 #ifndef SDL_MAIN_HANDLED
34 #if defined(__WIN32__)
35 /* On Windows SDL provides WinMain(), which parses the command line and passes
36  the arguments to your main function.
37 
38  If you provide your own WinMain(), you may define SDL_MAIN_HANDLED
39  */
40 #define SDL_MAIN_AVAILABLE
41 
42 #elif defined(__WINRT__)
43 /* On WinRT, SDL provides a main function that initializes CoreApplication,
44  creating an instance of IFrameworkView in the process.
45 
46  Please note that #include'ing SDL_main.h is not enough to get a main()
47  function working. In non-XAML apps, the file,
48  src/main/winrt/SDL_WinRT_main_NonXAML.cpp, or a copy of it, must be compiled
49  into the app itself. In XAML apps, the function, SDL_WinRTRunApp must be
50  called, with a pointer to the Direct3D-hosted XAML control passed in.
51 */
52 #define SDL_MAIN_NEEDED
53 
54 #elif defined(__GDK__)
55 /* On GDK, SDL provides a main function that initializes the game runtime.
56 
57  Please note that #include'ing SDL_main.h is not enough to get a main()
58  function working. You must either link against SDL2main or, if not possible,
59  call the SDL_GDKRunApp function from your entry point.
60 */
61 #define SDL_MAIN_NEEDED
62 
63 #elif defined(__IPHONEOS__)
64 /* On iOS SDL provides a main function that creates an application delegate
65  and starts the iOS application run loop.
66 
67  If you link with SDL dynamically on iOS, the main function can't be in a
68  shared library, so you need to link with libSDLmain.a, which includes a
69  stub main function that calls into the shared library to start execution.
70 
71  See src/video/uikit/SDL_uikitappdelegate.m for more details.
72  */
73 #define SDL_MAIN_NEEDED
74 
75 #elif defined(__ANDROID__)
76 /* On Android SDL provides a Java class in SDLActivity.java that is the
77  main activity entry point.
78 
79  See docs/README-android.md for more details on extending that class.
80  */
81 #define SDL_MAIN_NEEDED
82 
83 /* We need to export SDL_main so it can be launched from Java */
84 #define SDLMAIN_DECLSPEC DECLSPEC
85 
86 #elif defined(__NACL__)
87 /* On NACL we use ppapi_simple to set up the application helper code,
88  then wait for the first PSE_INSTANCE_DIDCHANGEVIEW event before
89  starting the user main function.
90  All user code is run in a separate thread by ppapi_simple, thus
91  allowing for blocking io to take place via nacl_io
92 */
93 #define SDL_MAIN_NEEDED
94 
95 #elif defined(__PSP__)
96 /* On PSP SDL provides a main function that sets the module info,
97  activates the GPU and starts the thread required to be able to exit
98  the software.
99 
100  If you provide this yourself, you may define SDL_MAIN_HANDLED
101  */
102 #define SDL_MAIN_AVAILABLE
103 
104 #elif defined(__PS2__)
105 #define SDL_MAIN_AVAILABLE
106 
107 #define SDL_PS2_SKIP_IOP_RESET() \
108  void reset_IOP(); \
109  void reset_IOP() {}
110 
111 #elif defined(__3DS__)
112 /*
113  On N3DS, SDL provides a main function that sets up the screens
114  and storage.
115 
116  If you provide this yourself, you may define SDL_MAIN_HANDLED
117 */
118 #define SDL_MAIN_AVAILABLE
119 
120 #endif
121 #endif /* SDL_MAIN_HANDLED */
122 
123 #ifndef SDLMAIN_DECLSPEC
124 #define SDLMAIN_DECLSPEC
125 #endif
126 
127 /**
128  * \file SDL_main.h
129  *
130  * The application's main() function must be called with C linkage,
131  * and should be declared like this:
132  * \code
133  * #ifdef __cplusplus
134  * extern "C"
135  * #endif
136  * int main(int argc, char *argv[])
137  * {
138  * }
139  * \endcode
140  */
141 
142 #if defined(SDL_MAIN_NEEDED) || defined(SDL_MAIN_AVAILABLE)
143 #define main SDL_main
144 #endif
145 
146 #include "begin_code.h"
147 #ifdef __cplusplus
148 extern "C" {
149 #endif
150 
151 /**
152  * The prototype for the application's main() function
153  */
154 typedef int (*SDL_main_func)(int argc, char *argv[]);
155 extern SDLMAIN_DECLSPEC int SDL_main(int argc, char *argv[]);
156 
157 
158 /**
159  * Circumvent failure of SDL_Init() when not using SDL_main() as an entry
160  * point.
161  *
162  * This function is defined in SDL_main.h, along with the preprocessor rule to
163  * redefine main() as SDL_main(). Thus to ensure that your main() function
164  * will not be changed it is necessary to define SDL_MAIN_HANDLED before
165  * including SDL.h.
166  *
167  * \since This function is available since SDL 2.0.0.
168  *
169  * \sa SDL_Init
170  */
171 extern DECLSPEC void SDLCALL SDL_SetMainReady(void);
172 
173 #if defined(__WIN32__) || defined(__GDK__)
174 
175 /**
176  * Register a win32 window class for SDL's use.
177  *
178  * This can be called to set the application window class at startup. It is
179  * safe to call this multiple times, as long as every call is eventually
180  * paired with a call to SDL_UnregisterApp, but a second registration attempt
181  * while a previous registration is still active will be ignored, other than
182  * to increment a counter.
183  *
184  * Most applications do not need to, and should not, call this directly; SDL
185  * will call it when initializing the video subsystem.
186  *
187  * \param name the window class name, in UTF-8 encoding. If NULL, SDL
188  * currently uses "SDL_app" but this isn't guaranteed.
189  * \param style the value to use in WNDCLASSEX::style. If `name` is NULL, SDL
190  * currently uses `(CS_BYTEALIGNCLIENT | CS_OWNDC)` regardless of
191  * what is specified here.
192  * \param hInst the HINSTANCE to use in WNDCLASSEX::hInstance. If zero, SDL
193  * will use `GetModuleHandle(NULL)` instead.
194  * \returns 0 on success, -1 on error. SDL_GetError() may have details.
195  *
196  * \since This function is available since SDL 2.0.2.
197  */
198 extern DECLSPEC int SDLCALL SDL_RegisterApp(const char *name, Uint32 style, void *hInst);
199 
200 /**
201  * Deregister the win32 window class from an SDL_RegisterApp call.
202  *
203  * This can be called to undo the effects of SDL_RegisterApp.
204  *
205  * Most applications do not need to, and should not, call this directly; SDL
206  * will call it when deinitializing the video subsystem.
207  *
208  * It is safe to call this multiple times, as long as every call is eventually
209  * paired with a prior call to SDL_RegisterApp. The window class will only be
210  * deregistered when the registration counter in SDL_RegisterApp decrements to
211  * zero through calls to this function.
212  *
213  * \since This function is available since SDL 2.0.2.
214  */
215 extern DECLSPEC void SDLCALL SDL_UnregisterApp(void);
216 
217 #endif /* defined(__WIN32__) || defined(__GDK__) */
218 
219 
220 #ifdef __WINRT__
221 
222 /**
223  * Initialize and launch an SDL/WinRT application.
224  *
225  * \param mainFunction the SDL app's C-style main(), an SDL_main_func
226  * \param reserved reserved for future use; should be NULL
227  * \returns 0 on success or -1 on failure; call SDL_GetError() to retrieve
228  * more information on the failure.
229  *
230  * \since This function is available since SDL 2.0.3.
231  */
232 extern DECLSPEC int SDLCALL SDL_WinRTRunApp(SDL_main_func mainFunction, void * reserved);
233 
234 #endif /* __WINRT__ */
235 
236 #if defined(__IPHONEOS__)
237 
238 /**
239  * Initializes and launches an SDL application.
240  *
241  * \param argc The argc parameter from the application's main() function
242  * \param argv The argv parameter from the application's main() function
243  * \param mainFunction The SDL app's C-style main(), an SDL_main_func
244  * \return the return value from mainFunction
245  *
246  * \since This function is available since SDL 2.0.10.
247  */
248 extern DECLSPEC int SDLCALL SDL_UIKitRunApp(int argc, char *argv[], SDL_main_func mainFunction);
249 
250 #endif /* __IPHONEOS__ */
251 
252 #ifdef __GDK__
253 
254 /**
255  * Initialize and launch an SDL GDK application.
256  *
257  * \param mainFunction the SDL app's C-style main(), an SDL_main_func
258  * \param reserved reserved for future use; should be NULL
259  * \returns 0 on success or -1 on failure; call SDL_GetError() to retrieve
260  * more information on the failure.
261  *
262  * \since This function is available since SDL 2.24.0.
263  */
264 extern DECLSPEC int SDLCALL SDL_GDKRunApp(SDL_main_func mainFunction, void *reserved);
265 
266 #endif /* __GDK__ */
267 
268 #ifdef __cplusplus
269 }
270 #endif
271 #include "close_code.h"
272 
273 #endif /* SDL_main_h_ */
274 
275 /* vi: set ts=4 sw=4 expandtab: */
void SDL_SetMainReady(void)
SDLMAIN_DECLSPEC int SDL_main(int argc, char *argv[])
#define SDLMAIN_DECLSPEC
Definition: SDL_main.h:124
int(* SDL_main_func)(int argc, char *argv[])
Definition: SDL_main.h:154
int SDL_RegisterApp(const char *name, Uint32 style, void *hInst)
void SDL_UnregisterApp(void)
uint32_t Uint32
Definition: SDL_stdinc.h:226