3 * This file has no copyright assigned and is placed in the Public Domain.
4 * This file is a part of the mingw-runtime package.
5 * No warranty is given; refer to the file DISCLAIMER within the package.
7 * Source code for the startup proceedures used by all programs. This code
8 * is compiled to make crt1.o, which should be located in the library path.
12 /* Hide the declaration of _fmode with dllimport attribute in stdlib.h to
13 avoid problems with older GCC. */
14 #define __IN_MINGW_RUNTIME
20 #define WIN32_LEAN_AND_MEAN
24 /* NOTE: The code for initializing the _argv, _argc, and environ variables
25 * has been moved to a separate .c file which is included in both
26 * crt1.c and dllcrt1.c. This means changes in the code don't have to
27 * be manually synchronized, but it does lead to this not-generally-
28 * a-good-idea use of include. */
30 #include "cpu_features.h"
32 extern void __main ();
33 extern void _pei386_runtime_relocator (void);
35 extern int main (int, char **, char **);
38 * Must have the correct app type for MSVCRT.
42 #define __UNKNOWN_APP 0
43 #define __CONSOLE_APP 1
45 __MINGW_IMPORT void __set_app_type(int);
46 #endif /* __MSVCRT__ */
48 /* Global _fmode for this .exe, not the one in msvcrt.dll,
49 The default is set in txtmode.o in libmingw32.a */
50 /* Override the dllimport'd declarations in stdlib.h */
54 extern int* __p__fmode(void); /* To access the dll _fmode */
58 * Setup the default file handles to have the _CRT_fmode mode, as well as
59 * any new files created by the user.
61 extern int _CRT_fmode;
64 _mingw32_init_fmode (void)
66 /* Don't set the std file mode if the user hasn't set any value for it. */
72 * This overrides the default file mode settings for stdin,
73 * stdout and stderr. At first I thought you would have to
74 * test with isatty, but it seems that the DOS console at
75 * least is smart enough to handle _O_BINARY stdout and
76 * still display correctly.
80 _setmode (_fileno (stdin), _CRT_fmode);
84 _setmode (_fileno (stdout), _CRT_fmode);
88 _setmode (_fileno (stderr), _CRT_fmode);
92 /* Now sync the dll _fmode to the one for this .exe. */
94 *__p__fmode() = _fmode;
96 *_imp___fmode_dll = _fmode;
100 /* This function will be called when a trap occurs. Thanks to Jacob
101 Navia for his contribution. */
103 _gnu_exception_handler (EXCEPTION_POINTERS * exception_data)
105 void (*old_handler) (int);
106 long action = EXCEPTION_CONTINUE_SEARCH;
109 switch (exception_data->ExceptionRecord->ExceptionCode)
111 case EXCEPTION_ACCESS_VIOLATION:
112 /* test if the user has set SIGSEGV */
113 old_handler = signal (SIGSEGV, SIG_DFL);
114 if (old_handler == SIG_IGN)
116 /* this is undefined if the signal was raised by anything other
118 signal (SIGSEGV, SIG_IGN);
119 action = EXCEPTION_CONTINUE_EXECUTION;
121 else if (old_handler != SIG_DFL)
123 /* This means 'old' is a user defined function. Call it */
124 (*old_handler) (SIGSEGV);
125 action = EXCEPTION_CONTINUE_EXECUTION;
129 case EXCEPTION_ILLEGAL_INSTRUCTION:
130 case EXCEPTION_PRIV_INSTRUCTION:
131 /* test if the user has set SIGILL */
132 old_handler = signal (SIGILL, SIG_DFL);
133 if (old_handler == SIG_IGN)
135 /* this is undefined if the signal was raised by anything other
137 signal (SIGILL, SIG_IGN);
138 action = EXCEPTION_CONTINUE_EXECUTION;
140 else if (old_handler != SIG_DFL)
142 /* This means 'old' is a user defined function. Call it */
143 (*old_handler) (SIGILL);
144 action = EXCEPTION_CONTINUE_EXECUTION;
148 case EXCEPTION_FLT_INVALID_OPERATION:
149 case EXCEPTION_FLT_DIVIDE_BY_ZERO:
150 case EXCEPTION_FLT_DENORMAL_OPERAND:
151 case EXCEPTION_FLT_OVERFLOW:
152 case EXCEPTION_FLT_UNDERFLOW:
153 case EXCEPTION_FLT_INEXACT_RESULT:
157 case EXCEPTION_INT_DIVIDE_BY_ZERO:
158 /* test if the user has set SIGFPE */
159 old_handler = signal (SIGFPE, SIG_DFL);
160 if (old_handler == SIG_IGN)
162 signal (SIGFPE, SIG_IGN);
165 action = EXCEPTION_CONTINUE_EXECUTION;
167 else if (old_handler != SIG_DFL)
169 /* This means 'old' is a user defined function. Call it */
170 (*old_handler) (SIGFPE);
171 action = EXCEPTION_CONTINUE_EXECUTION;
182 * The function mainCRTStartup is the entry point for all console programs.
184 static void __attribute__((noreturn))
185 __mingw_CRTStartup (void)
190 * Set up the top-level exception handler so that signal handling
191 * works as expected. The mapping between ANSI/POSIX signals and
192 * Win32 SE is not 1-to-1, so caveat emptore.
195 SetUnhandledExceptionFilter (_gnu_exception_handler);
198 * Initialize floating point unit.
200 __cpu_features_init (); /* Do we have SSE, etc.*/
201 _fpreset (); /* Supplied by the runtime library. */
204 * Set up __argc, __argv and _environ.
206 _mingw32_init_mainargs ();
209 * Sets the default file mode.
210 * If _CRT_fmode is set, also set mode for stdin, stdout
211 * and stderr, as well
212 * NOTE: DLLs don't do this because that would be rude!
214 _mingw32_init_fmode ();
216 /* Adust references to dllimported data that have non-zero offsets. */
217 _pei386_runtime_relocator ();
219 /* Align the stack to 16 bytes for the sake of SSE ops in main
220 or in functions inlined into main. */
221 asm __volatile__ ("andl $-16, %%esp" : : : "%esp");
223 /* From libgcc.a, __main calls global class constructors via
224 __do_global_ctors, This in turn registers __do_global_dtors
225 as the first entry of the app's atexit table. We do this
226 explicitly at app startup rather than rely on gcc to generate
227 the call in main's prologue, since main may be imported from a dll
228 which has its own __do_global_ctors. */
232 * Call the main function. If the user does not supply one
233 * the one in the 'libmingw32.a' library will be linked in, and
234 * that one calls WinMain. See main.c in the 'lib' dir
237 nRet = main (_argc, _argv, environ);
240 * Perform exit processing for the C library. This means
241 * flushing output and calling 'atexit' registered functions.
249 * The function mainCRTStartup is the entry point for all console programs.
252 mainCRTStartup (void)
255 __set_app_type (__CONSOLE_APP);
257 __mingw_CRTStartup ();
261 * For now the GUI startup function is the same as the console one.
262 * This simply gets rid of the annoying warning about not being able
263 * to find WinMainCRTStartup when linking GUI applications.
266 WinMainCRTStartup (void)
269 __set_app_type (__GUI_APP);
271 __mingw_CRTStartup ();
275 * We force use of library version of atexit, which is only
276 * visible in import lib as _imp__atexit
278 extern int (*_imp__atexit)(void (*)(void));
279 int atexit (void (* pfn )(void) )
281 return ( (*_imp__atexit)(pfn));
284 /* Likewise for non-ANSI _onexit */
285 extern _onexit_t (*_imp___onexit)(_onexit_t);
287 _onexit (_onexit_t pfn )
289 return (*_imp___onexit)(pfn);