win32/lib/crt1.c

   1 // =============================================
   2 // crt1.c
   3
   4 // For ExitProcess
   5 // windows.h header file should be included before any other library include
   6 #include <windows.h>
   7 #include <stdio.h>
   8 #include <stdlib.h>
   9
  10 #define _UNKNOWN_APP    0
  11 #define _CONSOLE_APP    1
  12 #define _GUI_APP        2
  13
  14 #define _MCW_PC         0x00030000 // Precision Control
  15 #define _PC_24          0x00020000 // 24 bits
  16 #define _PC_53          0x00010000 // 53 bits
  17 #define _PC_64          0x00000000 // 64 bits
  18
  19 typedef struct
  20 {
  21     int newmode;
  22 } _startupinfo;
  23
  24 // Prototype of __getmainargs:
  25 // in msvcrt v6.x : returns void (windows 98, 2000)
  26 // in msvcrt v7.x : returns int  (windows xp and above)
  27 // Using the last for check the result. A negative value means no success.
  28 // These are the test results of call to __getmainargs with the heap fully:
  29 // win 98, 2000 :
  30 //     program termination with error code 255 after call _amsg_exit(8)
  31 //     prints: "runtime error R6008\r\n- not enough space for arguments\r\n"
  32 // win xp :
  33 //     returns -1
  34 // win 7, 8 :
  35 //     program termination with error code -1 after call ExitProcess(-1)
  36 //
  37 // Checking the return of this function also works on windows 98 and 2000
  38 // because internally it sets to eax the value of the third parameter.
  39 // In this case is &env and at that point it is not a negative value.
  40
  41 int __cdecl __getmainargs(int *pargc, char ***pargv, char ***penv, int globb, _startupinfo*);
  42 void __cdecl __set_app_type(int apptype);
  43 unsigned int __cdecl _controlfp(unsigned int new_value, unsigned int mask);
  44
  45 void _start(void);
  46 int main(int argc, char * argv[], char * env[]);
  47
  48 void _start(void)
  49 {
  50     __TRY__
  51     int argc;
  52     char **argv;
  53     char **env;
  54     _startupinfo start_info;
  55
  56     // Sets the current application type
  57     __set_app_type(_CONSOLE_APP);
  58
  59     // Set default FP precision to 53 bits (8-byte double)
  60     // _MCW_PC (Precision control) is not supported on
  61     // the ARM and x64 architectures
  62 #if defined(_X86_) && !defined(__x86_64)
  63     _controlfp(_PC_53, _MCW_PC);
  64 #endif
  65
  66     start_info.newmode = 0;
  67     if ( __getmainargs( &argc, &argv, &env, 0, &start_info ) < 0 )
  68     {
  69         ExitProcess(-1);
  70     }
  71     else
  72     {
  73         exit( main(argc, argv, env) );
  74     }
  75
  76 }
  77
  78 // =============================================