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/**
23 * \file begin_code.h
24 *
25 * This file sets things up for C dynamic library function definitions,
26 * static inlined functions, and structures aligned at 4-byte alignment.
27 * If you don't like ugly C preprocessor code, don't look at this file. :)
28 */
29
30/* This shouldn't be nested -- included it around code only. */
31#ifdef _begin_code_h
32#error Nested inclusion of begin_code.h
33#endif
34#define _begin_code_h
35
36#ifndef SDL_DEPRECATED
37# if (__GNUC__ >= 4) /* technically, this arrived in gcc 3.1, but oh well. */
38# define SDL_DEPRECATED __attribute__((deprecated))
39# else
40# define SDL_DEPRECATED
41# endif
42#endif
43
44#ifndef SDL_UNUSED
45# ifdef __GNUC__
46# define SDL_UNUSED __attribute__((unused))
47# else
48# define SDL_UNUSED
49# endif
50#endif
51
52/* Some compilers use a special export keyword */
53#ifndef DECLSPEC
54# if defined(__WIN32__) || defined(__WINRT__) || defined(__CYGWIN__)
55# ifdef DLL_EXPORT
56# define DECLSPEC __declspec(dllexport)
57# else
58# define DECLSPEC
59# endif
60# elif defined(__OS2__)
61# ifdef BUILD_SDL
62# define DECLSPEC __declspec(dllexport)
63# else
64# define DECLSPEC
65# endif
66# else
67# if defined(__GNUC__) && __GNUC__ >= 4
68# define DECLSPEC __attribute__ ((visibility("default")))
69# else
70# define DECLSPEC
71# endif
72# endif
73#endif
74
75/* By default SDL uses the C calling convention */
76#ifndef SDLCALL
77#if (defined(__WIN32__) || defined(__WINRT__)) && !defined(__GNUC__)
78#define SDLCALL __cdecl
79#elif defined(__OS2__) || defined(__EMX__)
80#define SDLCALL _System
81# if defined (__GNUC__) && !defined(_System)
82# define _System /* for old EMX/GCC compat. */
83# endif
84#else
85#define SDLCALL
86#endif
87#endif /* SDLCALL */
88
89/* Removed DECLSPEC on Symbian OS because SDL cannot be a DLL in EPOC */
90#ifdef __SYMBIAN32__
91#undef DECLSPEC
92#define DECLSPEC
93#endif /* __SYMBIAN32__ */
94
95/* Force structure packing at 4 byte alignment.
96 This is necessary if the header is included in code which has structure
97 packing set to an alternate value, say for loading structures from disk.
98 The packing is reset to the previous value in close_code.h
99 */
100#if defined(_MSC_VER) || defined(__MWERKS__) || defined(__BORLANDC__)
101#ifdef _MSC_VER
102#pragma warning(disable: 4103)
103#endif
104#ifdef __clang__
105#pragma clang diagnostic ignored "-Wpragma-pack"
106#endif
107#ifdef __BORLANDC__
108#pragma nopackwarning
109#endif
110#ifdef _M_X64
111/* Use 8-byte alignment on 64-bit architectures, so pointers are aligned */
112#pragma pack(push,8)
113#else
114#pragma pack(push,4)
115#endif
116#endif /* Compiler needs structure packing set */
117
118#ifndef SDL_INLINE
119#if defined(__GNUC__)
120#define SDL_INLINE __inline__
121#elif defined(_MSC_VER) || defined(__BORLANDC__) || \
122 defined(__DMC__) || defined(__SC__) || \
123 defined(__WATCOMC__) || defined(__LCC__) || \
124 defined(__DECC) || defined(__CC_ARM)
125#define SDL_INLINE __inline
126#ifndef __inline__
127#define __inline__ __inline
128#endif
129#else
130#define SDL_INLINE inline
131#ifndef __inline__
132#define __inline__ inline
133#endif
134#endif
135#endif /* SDL_INLINE not defined */
136
137#ifndef SDL_FORCE_INLINE
138#if defined(_MSC_VER)
139#define SDL_FORCE_INLINE __forceinline
140#elif ( (defined(__GNUC__) && (__GNUC__ >= 4)) || defined(__clang__) )
141#define SDL_FORCE_INLINE __attribute__((always_inline)) static __inline__
142#else
143#define SDL_FORCE_INLINE static SDL_INLINE
144#endif
145#endif /* SDL_FORCE_INLINE not defined */
146
147#ifndef SDL_NORETURN
148#if defined(__GNUC__)
149#define SDL_NORETURN __attribute__((noreturn))
150#elif defined(_MSC_VER)
151#define SDL_NORETURN __declspec(noreturn)
152#else
153#define SDL_NORETURN
154#endif
155#endif /* SDL_NORETURN not defined */
156
157/* Apparently this is needed by several Windows compilers */
158#if !defined(__MACH__)
159#ifndef NULL
160#ifdef __cplusplus
161#define NULL 0
162#else
163#define NULL ((void *)0)
164#endif
165#endif /* NULL */
166#endif /* ! Mac OS X - breaks precompiled headers */
167
168#ifndef SDL_FALLTHROUGH
169#if (defined(__cplusplus) && __cplusplus >= 201703L) || \
170 (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 202000L)
171#define SDL_FALLTHROUGH [[fallthrough]]
172#else
173#if defined(__has_attribute)
174#define _HAS_FALLTHROUGH __has_attribute(__fallthrough__)
175#else
176#define _HAS_FALLTHROUGH 0
177#endif /* __has_attribute */
178#if _HAS_FALLTHROUGH && \
179 ((defined(__GNUC__) && __GNUC__ >= 7) || \
180 (defined(__clang_major__) && __clang_major__ >= 10))
181#define SDL_FALLTHROUGH __attribute__((__fallthrough__))
182#else
183#define SDL_FALLTHROUGH do {} while (0) /* fallthrough */
184#endif /* _HAS_FALLTHROUGH */
185#undef _HAS_FALLTHROUGH
186#endif /* C++17 or C2x */
187#endif /* SDL_FALLTHROUGH not defined */
188

source code of include/SDL2/begin_code.h