SDL  2.0
SDL_main.h
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1 /*
2  Simple DirectMedia Layer
3  Copyright (C) 1997-2021 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 #endif
87 #endif /* SDL_MAIN_HANDLED */
88 
89 #ifndef SDLMAIN_DECLSPEC
90 #define SDLMAIN_DECLSPEC
91 #endif
92 
93 /**
94  * \file SDL_main.h
95  *
96  * The application's main() function must be called with C linkage,
97  * and should be declared like this:
98  * \code
99  * #ifdef __cplusplus
100  * extern "C"
101  * #endif
102  * int main(int argc, char *argv[])
103  * {
104  * }
105  * \endcode
106  */
107 
108 #if defined(SDL_MAIN_NEEDED) || defined(SDL_MAIN_AVAILABLE)
109 #define main SDL_main
110 #endif
111 
112 #include "begin_code.h"
113 #ifdef __cplusplus
114 extern "C" {
115 #endif
116 
117 /**
118  * The prototype for the application's main() function
119  */
120 typedef int (*SDL_main_func)(int argc, char *argv[]);
121 extern SDLMAIN_DECLSPEC int SDL_main(int argc, char *argv[]);
122 
123 
124 /**
125  * Circumvent failure of SDL_Init() when not using SDL_main() as an entry
126  * point.
127  *
128  * This function is defined in SDL_main.h, along with the preprocessor rule to
129  * redefine main() as SDL_main(). Thus to ensure that your main() function
130  * will not be changed it is necessary to define SDL_MAIN_HANDLED before
131  * including SDL.h.
132  *
133  * \sa SDL_Init
134  */
135 extern DECLSPEC void SDLCALL SDL_SetMainReady(void);
136 
137 #ifdef __WIN32__
138 
139 /**
140  * This can be called to set the application class at startup
141  */
142 extern DECLSPEC int SDLCALL SDL_RegisterApp(char *name, Uint32 style, void *hInst);
143 extern DECLSPEC void SDLCALL SDL_UnregisterApp(void);
144 
145 #endif /* __WIN32__ */
146 
147 
148 #ifdef __WINRT__
149 
150 /**
151  * Initialize and launch an SDL/WinRT application.
152  *
153  * \param mainFunction the SDL app's C-style main(), an SDL_main_func
154  * \param reserved reserved for future use; should be NULL
155  * \returns 0 on success or -1 on failure; call SDL_GetError() to retrieve
156  * more information on the failure.
157  *
158  * \since This function is available since SDL 2.0.3.
159  */
160 extern DECLSPEC int SDLCALL SDL_WinRTRunApp(SDL_main_func mainFunction, void * reserved);
161 
162 #endif /* __WINRT__ */
163 
164 #if defined(__IPHONEOS__)
165 
166 /**
167  * Initializes and launches an SDL application.
168  *
169  * \param argc The argc parameter from the application's main() function
170  * \param argv The argv parameter from the application's main() function
171  * \param mainFunction The SDL app's C-style main(), an SDL_main_func
172  * \return the return value from mainFunction
173  */
174 extern DECLSPEC int SDLCALL SDL_UIKitRunApp(int argc, char *argv[], SDL_main_func mainFunction);
175 
176 #endif /* __IPHONEOS__ */
177 
178 
179 #ifdef __cplusplus
180 }
181 #endif
182 #include "close_code.h"
183 
184 #endif /* SDL_main_h_ */
185 
186 /* 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:90
int(* SDL_main_func)(int argc, char *argv[])
Definition: SDL_main.h:120
int SDL_RegisterApp(char *name, Uint32 style, void *hInst)
void SDL_UnregisterApp(void)
uint32_t Uint32
Definition: SDL_stdinc.h:209