reactos/lib/3rdparty/mingw/crt1.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 #define WIN32_LEAN_AND_MEAN
  21 #include <windows.h>
  22 #include <signal.h>
  23
  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. */
  29 #include "init.c"
  30 #include "cpu_features.h"
  31
  32 extern void _pei386_runtime_relocator (void);
  33
  34 extern int main (int, char **, char **);
  35
  36 /*
  37  * Must have the correct app type for MSVCRT.
  38  */
  39
  40 #ifdef __MSVCRT__
  41 #define __UNKNOWN_APP    0
  42 #define __CONSOLE_APP    1
  43 #define __GUI_APP        2
  44 #ifndef _M_PPC
  45 __MINGW_IMPORT
  46 #endif
  47 void __set_app_type(int);
  48 #endif /* __MSVCRT__ */
  49
  50 /*  Global _fmode for this .exe, not the one in msvcrt.dll,
  51     The default is set in txtmode.o in libmingw32.a */
  52 /* Override the dllimport'd declarations in stdlib.h */
  53 #undef _fmode
  54 extern int _fmode;
  55 #ifdef __MSVCRT__
  56 extern int* __p__fmode(void); /* To access the dll _fmode */
  57 #endif
  58
  59 /*
  60  * Setup the default file handles to have the _CRT_fmode mode, as well as
  61  * any new files created by the user.
  62  */
  63 extern int _CRT_fmode;
  64
  65 static void
  66 _mingw32_init_fmode (void)
  67 {
  68   /* Don't set the std file mode if the user hasn't set any value for it. */
  69   if (_CRT_fmode)
  70     {
  71       _fmode = _CRT_fmode;
  72
  73       /*
  74        * This overrides the default file mode settings for stdin,
  75        * stdout and stderr. At first I thought you would have to
  76        * test with isatty, but it seems that the DOS console at
  77        * least is smart enough to handle _O_BINARY stdout and
  78        * still display correctly.
  79        */
  80       if (stdin)
  81         {
  82           _setmode (_fileno (stdin), _CRT_fmode);
  83         }
  84       if (stdout)
  85         {
  86           _setmode (_fileno (stdout), _CRT_fmode);
  87         }
  88       if (stderr)
  89         {
  90           _setmode (_fileno (stderr), _CRT_fmode);
  91         }
  92     }
  93
  94     /*  Now sync  the dll _fmode to the  one for this .exe.  */
  95 #ifdef __MSVCRT__
  96     *__p__fmode() = _fmode;
  97 #else
  98     *_imp___fmode_dll = _fmode;
  99 #endif
 100 }
 101
 102 /* This function will be called when a trap occurs. Thanks to Jacob
 103    Navia for his contribution. */
 104 static LONG CALLBACK
 105 _gnu_exception_handler (EXCEPTION_POINTERS * exception_data)
 106 {
 107   void (*old_handler) (int);
 108   LONG action = EXCEPTION_CONTINUE_SEARCH;
 109   int reset_fpu = 0;
 110
 111   switch (exception_data->ExceptionRecord->ExceptionCode)
 112     {
 113     case EXCEPTION_ACCESS_VIOLATION:
 114       /* test if the user has set SIGSEGV */
 115       old_handler = signal (SIGSEGV, SIG_DFL);
 116       if (old_handler == SIG_IGN)
 117         {
 118           /* this is undefined if the signal was raised by anything other
 119              than raise ().  */
 120           signal (SIGSEGV, SIG_IGN);
 121           action = EXCEPTION_CONTINUE_EXECUTION;
 122         }
 123       else if (old_handler != SIG_DFL)
 124         {
 125           /* This means 'old' is a user defined function. Call it */
 126           (*old_handler) (SIGSEGV);
 127           action = EXCEPTION_CONTINUE_EXECUTION;
 128         }
 129       break;
 130
 131     case EXCEPTION_ILLEGAL_INSTRUCTION:
 132     case EXCEPTION_PRIV_INSTRUCTION:
 133       /* test if the user has set SIGILL */
 134       old_handler = signal (SIGILL, SIG_DFL);
 135       if (old_handler == SIG_IGN)
 136         {
 137           /* this is undefined if the signal was raised by anything other
 138              than raise ().  */
 139           signal (SIGILL, SIG_IGN);
 140           action = EXCEPTION_CONTINUE_EXECUTION;
 141         }
 142       else if (old_handler != SIG_DFL)
 143         {
 144           /* This means 'old' is a user defined function. Call it */
 145           (*old_handler) (SIGILL);
 146           action = EXCEPTION_CONTINUE_EXECUTION;
 147         }
 148       break;
 149
 150     case EXCEPTION_FLT_INVALID_OPERATION:
 151     case EXCEPTION_FLT_DIVIDE_BY_ZERO:
 152     case EXCEPTION_FLT_DENORMAL_OPERAND:
 153     case EXCEPTION_FLT_OVERFLOW:
 154     case EXCEPTION_FLT_UNDERFLOW:
 155     case EXCEPTION_FLT_INEXACT_RESULT:
 156       reset_fpu = 1;
 157       /* fall through. */
 158
 159     case EXCEPTION_INT_DIVIDE_BY_ZERO:
 160       /* test if the user has set SIGFPE */
 161       old_handler = signal (SIGFPE, SIG_DFL);
 162       if (old_handler == SIG_IGN)
 163         {
 164           signal (SIGFPE, SIG_IGN);
 165           if (reset_fpu)
 166             _fpreset ();
 167           action = EXCEPTION_CONTINUE_EXECUTION;
 168         }
 169       else if (old_handler != SIG_DFL)
 170         {
 171           /* This means 'old' is a user defined function. Call it */
 172           (*old_handler) (SIGFPE);
 173           action = EXCEPTION_CONTINUE_EXECUTION;
 174         }
 175       break;
 176
 177     default:
 178       break;
 179     }
 180   return action;
 181 }
 182
 183 /*
 184  * The function mainCRTStartup is the entry point for all console programs.
 185  */
 186 static void  __attribute__((noreturn))
 187 __mingw_CRTStartup (void)
 188 {
 189   int nRet;
 190
 191   /*
 192    * Set up the top-level exception handler so that signal handling
 193    * works as expected. The mapping between ANSI/POSIX signals and
 194    * Win32 SE is not 1-to-1, so caveat emptore.
 195    *
 196    */
 197   SetUnhandledExceptionFilter (_gnu_exception_handler);
 198
 199   /*
 200    * Initialize floating point unit.
 201    */
 202   __cpu_features_init ();       /* Do we have SSE, etc.*/
 203   _fpreset ();                  /* Supplied by the runtime library. */
 204
 205   /*
 206    * Set up __argc, __argv and _environ.
 207    */
 208   _mingw32_init_mainargs ();
 209
 210   /*
 211    * Sets the default file mode.
 212    * If _CRT_fmode is set, also set mode for stdin, stdout
 213    * and stderr, as well
 214    * NOTE: DLLs don't do this because that would be rude!
 215    */
 216   _mingw32_init_fmode ();
 217
 218    /* Adust references to dllimported data that have non-zero offsets.  */
 219 #if defined(__i386__)
 220   _pei386_runtime_relocator ();
 221 #endif
 222
 223 #if defined(__GNUC__)
 224 #if defined(__i386__)
 225   /* Align the stack to 16 bytes for the sake of SSE ops in main
 226      or in functions inlined into main.  */
 227   asm  __volatile__  ("andl $-16, %%esp" : : : "%esp");
 228 #elif defined(__mips__)
 229   /* Align the stack to 16 bytes */
 230   asm  __volatile__  ("andi %sp,%sp,-16" : : : "%sp");
 231 #elif defined(__PowerPC__)
 232   /* Align the stack to 16 bytes */
 233   asm  __volatile__  ("li 0,15\n\tandc 1,1,0" : : : "r1");
 234 #else
 235 #error Unsupported architecture
 236 #endif
 237 #elif defined(_MSC_VER)
 238 #if defined(_M_IX86)
 239   /* Align the stack to 16 bytes for the sake of SSE ops in main
 240      or in functions inlined into main.  */
 241   __asm and esp, 0FFFFFFF0h
 242 #else
 243 #error TODO
 244 #endif
 245 #else
 246 #error TODO
 247 #endif
 248
 249   /*
 250    * Call the main function. If the user does not supply one
 251    * the one in the 'libmingw32.a' library will be linked in, and
 252    * that one calls WinMain. See main.c in the 'lib' dir
 253    * for more details.
 254    */
 255   nRet = main (_argc, _argv, _environ);
 256
 257   /*
 258    * Perform exit processing for the C library. This means
 259    * flushing output and calling 'atexit' registered functions.
 260    */
 261   _cexit ();
 262
 263   ExitProcess (nRet);
 264 }
 265
 266 /*
 267  * The function mainCRTStartup is the entry point for all console programs.
 268  */
 269 void
 270 mainCRTStartup (void)
 271 {
 272 #ifdef __MSVCRT__
 273   __set_app_type (__CONSOLE_APP);
 274 #endif
 275   __mingw_CRTStartup ();
 276 }
 277
 278 /*
 279  * For now the GUI startup function is the same as the console one.
 280  * This simply gets rid of the annoying warning about not being able
 281  * to find WinMainCRTStartup when linking GUI applications.
 282  */
 283 void
 284 WinMainCRTStartup (void)
 285 {
 286 #ifdef __MSVCRT__
 287   __set_app_type (__GUI_APP);
 288 #endif
 289   __mingw_CRTStartup ();
 290 }
 291
 292 #if 0
 293 /*
 294  *  We force use of library version of atexit, which is only
 295  *  visible in import lib as _imp__atexit
 296  */
 297 extern int (*_imp__atexit)(void (*)(void));
 298 int atexit (void (* pfn )(void) )
 299 {
 300   return ( (*_imp__atexit)(pfn));
 301 }
 302
 303 /* Likewise for non-ANSI _onexit */
 304 extern _onexit_t (*_imp___onexit)(_onexit_t);
 305 _onexit_t
 306 _onexit (_onexit_t pfn )
 307 {
 308   return (*_imp___onexit)(pfn);
 309 }
 310 #endif