GNU libmicrohttpd 0.9.77
Loading...
Searching...
No Matches
autoinit_funcs.h
Go to the documentation of this file.
1/*
2 * AutoinitFuncs: Automatic Initialization and Deinitialization Functions
3 * Copyright(C) 2014-2023 Karlson2k (Evgeny Grin)
4 *
5 * This header is free software; you can redistribute it and / or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2.1 of the License, or (at your option) any later version.
9 *
10 * This header is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
14 *
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this header; if not, see
17 * <http://www.gnu.org/licenses/>.
18 */
19
20/*
21 General usage is simple: include this header, declare or define two
22 functions with zero parameters (void) and any return type: one for
23 initialisation and one for deinitialisation, add
24 _SET_INIT_AND_DEINIT_FUNCS(FuncInitName, FuncDeInitName) to the code
25 and functions will be automatically called during application startup
26 and shutdown.
27 This is useful for libraries as libraries don't have direct access
28 to main() functions.
29 Example:
30 -------------------------------------------------
31 #include <stdlib.h>
32 #include "autoinit_funcs.h"
33
34 int someVar;
35 void* somePtr;
36
37 void libInit(void)
38 {
39 someVar = 3;
40 somePtr = malloc(100);
41 }
42
43 void libDeinit(void)
44 {
45 free(somePtr);
46 }
47
48 _SET_INIT_AND_DEINIT_FUNCS(libInit,libDeinit);
49 -------------------------------------------------
50
51 If initialiser or deinitialiser function is not needed, just define
52 it as empty function.
53
54 This header should work with GCC, clang, MSVC (2010 or later) and
55 SunPro / Sun Studio / Oracle Solaris Studio / Oracle Developer Studio
56 compiler.
57 Supported C and C++ languages; application, static and dynamic (DLL)
58 libraries; non-optimized (Debug) and optimised (Release) compilation
59 and linking.
60
61 For more information see header code and comments in code.
62 */
63#ifndef AUTOINIT_FUNCS_INCLUDED
64#define AUTOINIT_FUNCS_INCLUDED 1
65
70#define AUTOINIT_FUNCS_VERSION 0x01001000
71
72#if defined(__GNUC__) || defined(__clang__)
73/* if possible - check for supported attribute */
74#ifdef __has_attribute
75#if ! __has_attribute (constructor) || ! __has_attribute (destructor)
76#define _GNUC_ATTR_CONSTR_NOT_SUPPORTED 1
77#endif /* !__has_attribute(constructor) || !__has_attribute(destructor) */
78#endif /* __has_attribute */
79#endif /* __GNUC__ */
80
81/* "__has_attribute__ ((constructor))" is supported by GCC, clang and
82 Sun/Oracle compiler starting from version 12.1. */
83#if ((defined(__GNUC__) || defined(__clang__)) && \
84 ! defined(_GNUC_ATTR_CONSTR_NOT_SUPPORTED)) || \
85 (defined(__SUNPRO_C) && __SUNPRO_C + 0 >= 0x5100)
86
87#define GNUC_SET_INIT_AND_DEINIT(FI,FD) \
88 void __attribute__ ((constructor)) _GNUC_init_helper_ ## FI (void); \
89 void __attribute__ ((destructor)) _GNUC_deinit_helper_ ## FD (void); \
90 void __attribute__ ((constructor)) _GNUC_init_helper_ ## FI (void) \
91 { (void) (FI) (); } \
92 void __attribute__ ((destructor)) _GNUC_deinit_helper_ ## FD (void) \
93 { (void) (FD) (); } \
94 struct _GNUC_dummy_str_ ## FI {int i;}
95
96#define _SET_INIT_AND_DEINIT_FUNCS(FI,FD) GNUC_SET_INIT_AND_DEINIT (FI,FD)
97#define _AUTOINIT_FUNCS_ARE_SUPPORTED 1
98
99#elif defined(_MSC_FULL_VER) && _MSC_VER + 0 >= 1600
100
101/* Make sure that your project/sources define:
102 _LIB if building a static library (_LIB is ignored if _CONSOLE is defined);
103 _USRDLL if building DLL-library;
104 not defined both _LIB and _USRDLL if building an application */
105
106/* Define AUTOINIT_FUNCS_DECLARE_STATIC_REG if you need macro declaration
107 for registering static initialisation functions even if you building DLL */
108/* Define AUTOINIT_FUNCS_FORCE_STATIC_REG if you want to set main macro
109 _SET_INIT_AND_DEINIT_FUNCS to static version even if building a DLL */
110
111/* Stringify macros */
112#define _INSTRMACRO(a) #a
113#define _STRMACRO(a) _INSTRMACRO (a)
114
115#if ! defined(_USRDLL) || defined(AUTOINIT_FUNCS_DECLARE_STATIC_REG) \
116 || defined(AUTOINIT_FUNCS_FORCE_STATIC_REG)
117
118/* Use "C" linkage for variable to simplify variable decoration */
119#ifdef __cplusplus
120#define W32_INITVARDECL extern "C"
121#else
122#define W32_INITVARDECL extern
123#endif
124
125/* How variable is decorated by compiler */
126#if (defined(_WIN32) || defined(_WIN64)) \
127 && ! defined(_M_IX86) && ! defined(_X86_)
128#if ! defined(_M_X64) && ! defined(_M_AMD64) && ! defined(_x86_64_) \
129 && ! defined(_M_ARM) && ! defined(_M_ARM64)
130#pragma message(__FILE__ "(" _STRMACRO(__LINE__) ") : warning AIFW001 : " \
131 "Untested architecture, linker may fail with unresolved symbol")
132#endif /* ! _M_X64 && ! _M_AMD64 && ! _x86_64_ && ! _M_ARM && ! _M_ARM64 */
133#define W32_VARDECORPREFIX
134#define W32_DECORVARNAME(v) v
135#define W32_VARDECORPREFIXSTR ""
136#elif defined(_WIN32) && (defined(_M_IX86) || defined(_X86_))
137#define W32_VARDECORPREFIX _
138#define W32_DECORVARNAME(v) _ ## v
139#define W32_VARDECORPREFIXSTR "_"
140#else
141#error Do not know how to decorate symbols for this architecture
142#endif
143
144/* Internal variable prefix (can be any) */
145#define W32_INITHELPERVARNAME(f) _initHelperDummy_ ## f
146#define W32_INITHELPERVARNAMEDECORSTR(f) \
147 W32_VARDECORPREFIXSTR _STRMACRO (W32_INITHELPERVARNAME (f))
148
149/* Declare section (segment), put variable pointing to init function to chosen segment,
150 force linker to always include variable to avoid omitting by optimiser */
151/* Initialisation function must be declared as
152 void __cdecl FuncName(void) */
153/* "extern" with initialisation value means that variable is declared AND defined. */
154#define W32_VFPTR_IN_SEG(S,F) \
155 __pragma (section (S,long,read)) \
156 __pragma (comment (linker, "/INCLUDE:" W32_INITHELPERVARNAMEDECORSTR (F))) \
157 W32_INITVARDECL __declspec(allocate (S))void \
158 (__cdecl * W32_INITHELPERVARNAME (F))(void) = &F
159
160/* Sections (segments) for pointers to initialisers/deinitialisers */
161
162/* Semi-officially suggested section for early initialisers (called before
163 C++ objects initialisers), "void" return type */
164#define W32_SEG_INIT_EARLY ".CRT$XCT"
165/* Semi-officially suggested section for late initialisers (called after
166 C++ objects initialisers), "void" return type */
167#define W32_SEG_INIT_LATE ".CRT$XCV"
168
169/* Unsafe sections (segments) for pointers to initialisers/deinitialisers */
170
171/* C++ lib initialisers, "void" return type (reserved by the system!) */
172#define W32_SEG_INIT_CXX_LIB ".CRT$XCL"
173/* C++ user initialisers, "void" return type (reserved by the system!) */
174#define W32_SEG_INIT_CXX_USER ".CRT$XCU"
175
176
177/* Declare section (segment), put variable pointing to init function to chosen segment,
178 force linker to always include variable to avoid omitting by optimiser */
179/* Initialisation function must be declared as
180 int __cdecl FuncName(void) */
181/* Startup process is aborted if initialiser returns non-zero */
182/* "extern" with initialisation value means that variable is declared AND defined. */
183#define W32_IFPTR_IN_SEG(S,F) \
184 __pragma (section (S,long,read)) \
185 __pragma (comment (linker, "/INCLUDE:" W32_INITHELPERVARNAMEDECORSTR (F))) \
186 W32_INITVARDECL __declspec(allocate (S))int \
187 (__cdecl * W32_INITHELPERVARNAME (F))(void) = &F
188
189/* Unsafe sections (segments) for pointers to initialisers with
190 "int" return type */
191
192/* C lib initialisers, "int" return type (reserved by the system!).
193 These initialisers are called before others. */
194#define W32_SEG_INIT_C_LIB ".CRT$XIL"
195/* C user initialisers, "int" return type (reserved by the system!).
196 These initialisers are called before others. */
197#define W32_SEG_INIT_C_USER ".CRT$XIU"
198
199
200/* Declare macro for different initialisers sections */
201/* Macro can be used several times to register several initialisers */
202/* Once function is registered as initialiser, it will be called automatically
203 during application startup */
204#define W32_REG_INIT_EARLY(F) W32_VFPTR_IN_SEG (W32_SEG_INIT_EARLY,F)
205#define W32_REG_INIT_LATE(F) W32_VFPTR_IN_SEG (W32_SEG_INIT_LATE,F)
206
207
208/* Not recommended / unsafe */
209/* "lib" initialisers are called before "user" initialisers */
210/* "C" initialisers are called before "C++" initialisers */
211#define W32_REG_INIT_C_USER(F) W32_FPTR_IN_SEG (W32_SEG_INIT_C_USER,F)
212#define W32_REG_INIT_C_LIB(F) W32_FPTR_IN_SEG (W32_SEG_INIT_C_LIB,F)
213#define W32_REG_INIT_CXX_USER(F) W32_FPTR_IN_SEG (W32_SEG_INIT_CXX_USER,F)
214#define W32_REG_INIT_CXX_LIB(F) W32_FPTR_IN_SEG (W32_SEG_INIT_CXX_LIB,F)
215
216/* Choose main register macro based on language and program type */
217/* Assuming that _LIB or _USRDLL is defined for static or DLL-library */
218/* Macro can be used several times to register several initialisers */
219/* Once function is registered as initialiser, it will be called automatically
220 during application startup */
221/* Define AUTOINIT_FUNCS_FORCE_EARLY_INIT to force register as early
222 initialiser */
223/* Define AUTOINIT_FUNCS_FORCE_LATE_INIT to force register as late
224 initialiser */
225/* By default C++ static or DLL-library code and any C code and will be
226 registered as early initialiser, while C++ non-library code will be
227 registered as late initialiser */
228#if (! defined(__cplusplus) || \
229 ((defined(_LIB) && ! defined(_CONSOLE)) || defined(_USRDLL)) || \
230 defined(AUTOINIT_FUNCS_FORCE_EARLY_INIT)) && \
231 ! defined(AUTOINIT_FUNCS_FORCE_LATE_INIT)
232#define W32_REGISTER_INIT(F) W32_REG_INIT_EARLY(F)
233#else
234#define W32_REGISTER_INIT(F) W32_REG_INIT_LATE(F)
235#endif
236
237#endif /* ! _USRDLL || ! AUTOINIT_FUNCS_DECLARE_STATIC_REG
238 || AUTOINIT_FUNCS_FORCE_STATIC_REG */
239
240
241#if ! defined(_USRDLL) || defined(AUTOINIT_FUNCS_FORCE_STATIC_REG)
242
243#include <stdlib.h> /* required for atexit() */
244
245#define W32_SET_INIT_AND_DEINIT(FI,FD) \
246 void __cdecl _W32_init_helper_ ## FI (void); \
247 void __cdecl _W32_deinit_helper_ ## FD (void); \
248 void __cdecl _W32_init_helper_ ## FI (void) \
249 { (void) (FI) (); atexit (_W32_deinit_helper_ ## FD); } \
250 void __cdecl _W32_deinit_helper_ ## FD (void) \
251 { (void) (FD) (); } \
252 W32_REGISTER_INIT (_W32_init_helper_ ## FI)
253#else /* _USRDLL */
254
255#ifndef WIN32_LEAN_AND_MEAN
256#define WIN32_LEAN_AND_MEAN 1
257#endif /* WIN32_LEAN_AND_MEAN */
258
259#include <Windows.h> /* Required for DllMain */
260
261/* If DllMain is already present in code, define AUTOINIT_FUNCS_CALL_USR_DLLMAIN
262 and rename DllMain to usr_DllMain */
263#ifndef AUTOINIT_FUNCS_CALL_USR_DLLMAIN
264#define W32_SET_INIT_AND_DEINIT(FI,FD) \
265 BOOL WINAPI DllMain (HINSTANCE hinst,DWORD reason,LPVOID unused); \
266 BOOL WINAPI DllMain (HINSTANCE hinst,DWORD reason,LPVOID unused) \
267 { (void) hinst; (void) unused; \
268 if (DLL_PROCESS_ATTACH==reason) {(void) (FI) ();} \
269 else if (DLL_PROCESS_DETACH==reason) {(void) (FD) ();} \
270 return TRUE; \
271 } struct _W32_dummy_strc_ ## FI {int i;}
272#else /* AUTOINIT_FUNCS_CALL_USR_DLLMAIN */
273#define W32_SET_INIT_AND_DEINIT(FI,FD) \
274 BOOL WINAPI usr_DllMain (HINSTANCE hinst,DWORD reason,LPVOID unused); \
275 BOOL WINAPI DllMain (HINSTANCE hinst,DWORD reason,LPVOID unused); \
276 BOOL WINAPI DllMain (HINSTANCE hinst,DWORD reason,LPVOID unused) \
277 { if (DLL_PROCESS_ATTACH==reason) {(void) (FI) ();} \
278 else if (DLL_PROCESS_DETACH==reason) {(void) (FD) ();} \
279 return usr_DllMain (hinst,reason,unused); \
280 } struct _W32_dummy_strc_ ## FI {int i;}
281#endif /* AUTOINIT_FUNCS_CALL_USR_DLLMAIN */
282#endif /* _USRDLL */
283
284#define _SET_INIT_AND_DEINIT_FUNCS(FI,FD) W32_SET_INIT_AND_DEINIT (FI,FD)
285/* Indicate that automatic initialisers/deinitialisers are supported */
286#define _AUTOINIT_FUNCS_ARE_SUPPORTED 1
287
288#else /* !__GNUC__ && !_MSC_FULL_VER */
289
290/* Define EMIT_ERROR_IF_AUTOINIT_FUNCS_ARE_NOT_SUPPORTED before inclusion of header to
291 abort compilation if automatic initialisers/deinitialisers are not supported */
292#ifdef EMIT_ERROR_IF_AUTOINIT_FUNCS_ARE_NOT_SUPPORTED
293#error \
294 Compiler/platform does not support automatic calls of user-defined initializer and deinitializer
295#endif /* EMIT_ERROR_IF_AUTOINIT_FUNCS_ARE_NOT_SUPPORTED */
296
297/* Do nothing */
298#define _SET_INIT_AND_DEINIT_FUNCS(FI,FD)
299/* Indicate that automatic initialisers/deinitialisers are not supported */
300#define _AUTOINIT_FUNCS_ARE_NOT_SUPPORTED 1
301
302#endif /* !__GNUC__ && !_MSC_FULL_VER */
303#endif /* !AUTOINIT_FUNCS_INCLUDED */