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(__IPHONEOS__)
55 /* On iOS SDL provides a main function that creates an application delegate
56  and starts the iOS application run loop.
57 
58  If you link with SDL dynamically on iOS, the main function can't be in a
59  shared library, so you need to link with libSDLmain.a, which includes a
60  stub main function that calls into the shared library to start execution.
61 
62  See src/video/uikit/SDL_uikitappdelegate.m for more details.
63  */
64 #define SDL_MAIN_NEEDED
65 
66 #elif defined(__ANDROID__)
67 /* On Android SDL provides a Java class in SDLActivity.java that is the
68  main activity entry point.
69 
70  See docs/README-android.md for more details on extending that class.
71  */
72 #define SDL_MAIN_NEEDED
73 
74 /* We need to export SDL_main so it can be launched from Java */
75 #define SDLMAIN_DECLSPEC DECLSPEC
76 
77 #elif defined(__NACL__)
78 /* On NACL we use ppapi_simple to set up the application helper code,
79  then wait for the first PSE_INSTANCE_DIDCHANGEVIEW event before
80  starting the user main function.
81  All user code is run in a separate thread by ppapi_simple, thus
82  allowing for blocking io to take place via nacl_io
83 */
84 #define SDL_MAIN_NEEDED
85 
86 #elif defined(__PSP__)
87 /* On PSP SDL provides a main function that sets the module info,
88  activates the GPU and starts the thread required to be able to exit
89  the software.
90 
91  If you provide this yourself, you may define SDL_MAIN_HANDLED
92  */
93 #define SDL_MAIN_AVAILABLE
94 
95 #endif
96 #endif /* SDL_MAIN_HANDLED */
97 
98 #ifndef SDLMAIN_DECLSPEC
99 #define SDLMAIN_DECLSPEC
100 #endif
101 
102 /**
103  * \file SDL_main.h
104  *
105  * The application's main() function must be called with C linkage,
106  * and should be declared like this:
107  * \code
108  * #ifdef __cplusplus
109  * extern "C"
110  * #endif
111  * int main(int argc, char *argv[])
112  * {
113  * }
114  * \endcode
115  */
116 
117 #if defined(SDL_MAIN_NEEDED) || defined(SDL_MAIN_AVAILABLE)
118 #define main SDL_main
119 #endif
120 
121 #include "begin_code.h"
122 #ifdef __cplusplus
123 extern "C" {
124 #endif
125 
126 /**
127  * The prototype for the application's main() function
128  */
129 typedef int (*SDL_main_func)(int argc, char *argv[]);
130 extern SDLMAIN_DECLSPEC int SDL_main(int argc, char *argv[]);
131 
132 
133 /**
134  * Circumvent failure of SDL_Init() when not using SDL_main() as an entry
135  * point.
136  *
137  * This function is defined in SDL_main.h, along with the preprocessor rule to
138  * redefine main() as SDL_main(). Thus to ensure that your main() function
139  * will not be changed it is necessary to define SDL_MAIN_HANDLED before
140  * including SDL.h.
141  *
142  * \since This function is available since SDL 2.0.0.
143  *
144  * \sa SDL_Init
145  */
146 extern DECLSPEC void SDLCALL SDL_SetMainReady(void);
147 
148 #ifdef __WIN32__
149 
150 /**
151  * Register a win32 window class for SDL's use.
152  *
153  * This can be called to set the application window class at startup. It is
154  * safe to call this multiple times, as long as every call is eventually
155  * paired with a call to SDL_UnregisterApp, but a second registration attempt
156  * while a previous registration is still active will be ignored, other than
157  * to increment a counter.
158  *
159  * Most applications do not need to, and should not, call this directly; SDL
160  * will call it when initializing the video subsystem.
161  *
162  * \param name the window class name, in UTF-8 encoding. If NULL, SDL
163  * currently uses "SDL_app" but this isn't guaranteed.
164  * \param style the value to use in WNDCLASSEX::style. If `name` is NULL, SDL
165  * currently uses `(CS_BYTEALIGNCLIENT | CS_OWNDC)` regardless of
166  * what is specified here.
167  * \param hInst the HINSTANCE to use in WNDCLASSEX::hInstance. If zero, SDL
168  * will use `GetModuleHandle(NULL)` instead.
169  * \returns 0 on success, -1 on error. SDL_GetError() may have details.
170  *
171  * \since This function is available since SDL 2.0.2.
172  */
173 extern DECLSPEC int SDLCALL SDL_RegisterApp(const char *name, Uint32 style, void *hInst);
174 
175 /**
176  * Deregister the win32 window class from an SDL_RegisterApp call.
177  *
178  * This can be called to undo the effects of SDL_RegisterApp.
179  *
180  * Most applications do not need to, and should not, call this directly; SDL
181  * will call it when deinitializing the video subsystem.
182  *
183  * It is safe to call this multiple times, as long as every call is eventually
184  * paired with a prior call to SDL_RegisterApp. The window class will only be
185  * deregistered when the registration counter in SDL_RegisterApp decrements to
186  * zero through calls to this function.
187  *
188  * \since This function is available since SDL 2.0.2.
189  */
190 extern DECLSPEC void SDLCALL SDL_UnregisterApp(void);
191 
192 #endif /* __WIN32__ */
193 
194 
195 #ifdef __WINRT__
196 
197 /**
198  * Initialize and launch an SDL/WinRT application.
199  *
200  * \param mainFunction the SDL app's C-style main(), an SDL_main_func
201  * \param reserved reserved for future use; should be NULL
202  * \returns 0 on success or -1 on failure; call SDL_GetError() to retrieve
203  * more information on the failure.
204  *
205  * \since This function is available since SDL 2.0.3.
206  */
207 extern DECLSPEC int SDLCALL SDL_WinRTRunApp(SDL_main_func mainFunction, void * reserved);
208 
209 #endif /* __WINRT__ */
210 
211 #if defined(__IPHONEOS__)
212 
213 /**
214  * Initializes and launches an SDL application.
215  *
216  * \param argc The argc parameter from the application's main() function
217  * \param argv The argv parameter from the application's main() function
218  * \param mainFunction The SDL app's C-style main(), an SDL_main_func
219  * \return the return value from mainFunction
220  *
221  * \since This function is available since SDL 2.0.10.
222  */
223 extern DECLSPEC int SDLCALL SDL_UIKitRunApp(int argc, char *argv[], SDL_main_func mainFunction);
224 
225 #endif /* __IPHONEOS__ */
226 
227 
228 #ifdef __cplusplus
229 }
230 #endif
231 #include "close_code.h"
232 
233 #endif /* SDL_main_h_ */
234 
235 /* 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:99
int(* SDL_main_func)(int argc, char *argv[])
Definition: SDL_main.h:129
int SDL_RegisterApp(const char *name, Uint32 style, void *hInst)
void SDL_UnregisterApp(void)
uint32_t Uint32
Definition: SDL_stdinc.h:220