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Secure CRT code sample

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When built in debug mode with the Visual Studio 2005 Community Technology Preview May 2004, the following source code:

 

#include <stdio.h>

#include <stdlib.h> // _invalid_parameter_handler, _set_invalid_parameter_handler

#include <tchar.h>

#include <crtdbg.h>

#include <errno.h>

void myInvalidParameterHandler( const wchar_t * expression,

                                const wchar_t * function,

                                const wchar_t * file,

                                unsigned int line,

                                uintptr_t pReserved )

{

   printf( _T("Invalid parameter detected in function %S. File: %S Line: %d\n"), function, file, line ) ;

   printf( _T("Expression: %S\n\n"), expression ) ;

}

void _tmain()

{

   _invalid_parameter_handler oldHandler = _set_invalid_parameter_handler( myInvalidParameterHandler ) ;

   _CrtSetReportMode( _CRT_ASSERT, 0 ) ; // Disable the message box for assertions.

   _ASSERTE( -1 == printf( NULL ) && EINVAL == errno ) ;

   _ASSERTE( EINVAL == printf_s( NULL ) ) ;

   TCHAR * fromBuffer = _T("Maître Corbeau, sur un arbre perché, Tenait en son bec un fromage." ) ;

   TCHAR toBuffer[10] ;

   // warning C4996: 'strcpy' was declared deprecated

   // _tcscpy( toBuffer, fromBuffer ) ;

   _ASSERTE( ERANGE == _tcscpy_s( toBuffer, sizeof(toBuffer) / sizeof(toBuffer[0]), fromBuffer ) ) ;

} 

 

outputs:

 

Invalid parameter detected in function printf. File: printf.c Line: 53
Expression: (format != ((void *)0))

Invalid parameter detected in function vprintf_helper. File: vprintf.c Line: 51
Expression: (format != ((void *)0))

Invalid parameter detected in function strcpy_s. File: strcat_s.c Line: 112
Expression: ("Buffer too small", 0)

 

And in release mode, it outputs ... nothing.

Comments

  • Anonymous
    June 09, 2004
    C++ assert macros only apply to debug mode...

    http://msdn.microsoft.com/library/default.asp?url=/library/en-us/vclib/html/crt__assert.2c._asserte_macros.asp
  • Anonymous
    June 09, 2004
    Good point Sean but mine was that myInvalidParameterHandler is not called in release mode. I should have been more specific. Thanks!
  • Anonymous
    June 09, 2004
    ah, so that's what you're getting at! ;)
  • Anonymous
    June 10, 2004
    The comment has been removed
  • Anonymous
    June 10, 2004
    Indeed! Sorry about that. And I realize that I did not understand Sean comment either which I'm sure was saying the same. Look for a follow-up post. Thanks guys!