lib/3rdparty/mingw/wcrt1.c

   1 /*
   2  * crt1.c
   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.
   6  *
   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.
   9  *
  10  */
  11
  12 /* Hide the declaration of _fmode with dllimport attribute in stdlib.h to
  13    avoid problems with older GCC. */
  14 #define __IN_MINGW_RUNTIME
  15 #include <stdlib.h>
  16 #include <stdio.h>
  17 #include <io.h>
  18 #include <process.h>
  19 #include <float.h>
  20 #include <math.h>
  21 #define WIN32_LEAN_AND_MEAN
  22 #include <windows.h>
  23 #include <signal.h>
  24
  25 /* NOTE: The code for initializing the _argv, _argc, and environ variables
  26  *       has been moved to a separate .c file which is included in both
  27  *       crt1.c and dllcrt1.c. This means changes in the code don't have to
  28  *       be manually synchronized, but it does lead to this not-generally-
  29  *       a-good-idea use of include. */
  30 #include "winit.c"
  31 #include "cpu_features.h"
  32
  33 extern void _pei386_runtime_relocator (void);
  34
  35 extern int wmain (int, wchar_t **, wchar_t **);
  36
  37 /*
  38  * Must have the correct app type for MSVCRT.
  39  */
  40
  41 #ifdef __MSVCRT__
  42 #define __UNKNOWN_APP    0
  43 #define __CONSOLE_APP    1
  44 #define __GUI_APP        2
  45 __MINGW_IMPORT void __set_app_type(int);
  46 #endif /* __MSVCRT__ */
  47
  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 */
  51 #undef _fmode
  52 extern int _fmode;
  53 #ifdef __MSVCRT__
  54 extern int* __p__fmode(void); /* To access the dll _fmode */
  55 #endif
  56
  57 /*
  58  * Setup the default file handles to have the _CRT_fmode mode, as well as
  59  * any new files created by the user.
  60  */
  61 extern int _CRT_fmode;
  62
  63 static void
  64 _mingw32_init_fmode (void)
  65 {
  66   /* Don't set the std file mode if the user hasn't set any value for it. */
  67   if (_CRT_fmode)
  68     {
  69       _fmode = _CRT_fmode;
  70
  71       /*
  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.
  77        */
  78       if (stdin)
  79         {
  80           _setmode (_fileno (stdin), _CRT_fmode);
  81         }
  82       if (stdout)
  83         {
  84           _setmode (_fileno (stdout), _CRT_fmode);
  85         }
  86       if (stderr)
  87         {
  88           _setmode (_fileno (stderr), _CRT_fmode);
  89         }
  90     }
  91
  92     /*  Now sync  the dll _fmode to the  one for this .exe.  */
  93 #ifdef __MSVCRT__
  94     *__p__fmode() = _fmode;
  95 #else
  96     *_imp___fmode_dll = _fmode;
  97 #endif
  98 }
  99
 100 /* This function will be called when a trap occurs. Thanks to Jacob
 101    Navia for his contribution. */
 102 static LONG CALLBACK
 103 _gnu_exception_handler (EXCEPTION_POINTERS * exception_data)
 104 {
 105   void (*old_handler) (int);
 106   LONG action = EXCEPTION_CONTINUE_SEARCH;
 107   int reset_fpu = 0;
 108
 109   switch (exception_data->ExceptionRecord->ExceptionCode)
 110     {
 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)
 115         {
 116           /* this is undefined if the signal was raised by anything other
 117              than raise ().  */
 118           signal (SIGSEGV, SIG_IGN);
 119           action = EXCEPTION_CONTINUE_EXECUTION;
 120         }
 121       else if (old_handler != SIG_DFL)
 122         {
 123           /* This means 'old' is a user defined function. Call it */
 124           (*old_handler) (SIGSEGV);
 125           action = EXCEPTION_CONTINUE_EXECUTION;
 126         }
 127       break;
 128
 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)
 134         {
 135           /* this is undefined if the signal was raised by anything other
 136              than raise ().  */
 137           signal (SIGILL, SIG_IGN);
 138           action = EXCEPTION_CONTINUE_EXECUTION;
 139         }
 140       else if (old_handler != SIG_DFL)
 141         {
 142           /* This means 'old' is a user defined function. Call it */
 143           (*old_handler) (SIGILL);
 144           action = EXCEPTION_CONTINUE_EXECUTION;
 145         }
 146       break;
 147
 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:
 154       reset_fpu = 1;
 155       /* fall through. */
 156
 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)
 161         {
 162           signal (SIGFPE, SIG_IGN);
 163           if (reset_fpu)
 164             _fpreset ();
 165           action = EXCEPTION_CONTINUE_EXECUTION;
 166         }
 167       else if (old_handler != SIG_DFL)
 168         {
 169           /* This means 'old' is a user defined function. Call it */
 170           (*old_handler) (SIGFPE);
 171           action = EXCEPTION_CONTINUE_EXECUTION;
 172         }
 173       break;
 174
 175     default:
 176       break;
 177     }
 178   return action;
 179 }
 180
 181 /*
 182  * The function mainCRTStartup is the entry point for all console programs.
 183  */
 184 static void  __attribute__((noreturn))
 185 __mingw_wCRTStartup (void)
 186 {
 187   int nRet;
 188
 189   /*
 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.
 193    *
 194    */
 195   SetUnhandledExceptionFilter (_gnu_exception_handler);
 196
 197   /*
 198    * Initialize floating point unit.
 199    */
 200   __cpu_features_init ();       /* Do we have SSE, etc.*/
 201   _fpreset ();                  /* Supplied by the runtime library. */
 202
 203   /*
 204    * Set up __argc, __argv and _wenviron.
 205    */
 206   _mingw32_init_wmainargs ();
 207
 208   /*
 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!
 213    */
 214   _mingw32_init_fmode ();
 215
 216    /* Adust references to dllimported data that have non-zero offsets.  */
 217 #if defined(__i386__)
 218   _pei386_runtime_relocator ();
 219 #endif
 220
 221 #if defined(__i386__)
 222   /* Align the stack to 16 bytes for the sake of SSE ops in main
 223      or in functions inlined into main.  */
 224   asm  __volatile__  ("andl $-16, %%esp" : : : "%esp");
 225 #elif defined(__mips__)
 226   /* Align the stack to 16 bytes */
 227   asm  __volatile__  ("andi %sp,%sp,-16" : : : "%sp");
 228 #elif defined(__PowerPC__)
 229   /* Align the stack to 16 bytes */
 230   asm  __volatile__  ("li 0,15\n\tandc 1,1,0" : : : "r1");
 231 #else
 232 #error Unsupported architecture
 233 #endif
 234
 235   /*
 236    * Call the main function. If the user does not supply one
 237    * the one in the 'libmingw32.a' library will be linked in, and
 238    * that one calls WinMain. See main.c in the 'lib' dir
 239    * for more details.
 240    */
 241   nRet = wmain (_argc, _wargv, _wenviron);
 242
 243   /*
 244    * Perform exit processing for the C library. This means
 245    * flushing output and calling 'atexit' registered functions.
 246    */
 247   _cexit ();
 248
 249   ExitProcess (nRet);
 250 }
 251
 252 /*
 253  * The function mainCRTStartup is the entry point for all console programs.
 254  */
 255 void
 256 wmainCRTStartup (void)
 257 {
 258 #ifdef __MSVCRT__
 259   __set_app_type (__CONSOLE_APP);
 260 #endif
 261   __mingw_wCRTStartup ();
 262 }
 263
 264 /*
 265  * For now the GUI startup function is the same as the console one.
 266  * This simply gets rid of the annoying warning about not being able
 267  * to find WinMainCRTStartup when linking GUI applications.
 268  */
 269 void
 270 wWinMainCRTStartup (void)
 271 {
 272 #ifdef __MSVCRT__
 273   __set_app_type (__GUI_APP);
 274 #endif
 275   __mingw_wCRTStartup ();
 276 }
 277
 278 #if 0
 279 /*
 280  *  We force use of library version of atexit, which is only
 281  *  visible in import lib as _imp__atexit
 282  */
 283 extern int (*_imp__atexit)(void (*)(void));
 284 int atexit (void (* pfn )(void) )
 285 {
 286   return ( (*_imp__atexit)(pfn));
 287 }
 288
 289 /* Likewise for non-ANSI _onexit */
 290 extern _onexit_t (*_imp___onexit)(_onexit_t);
 291 _onexit_t
 292 _onexit (_onexit_t pfn )
 293 {
 294   return (*_imp___onexit)(pfn);
 295 }
 296 #endif