Re: [Mingw-w64-public] why aren't "secure" _s functions provided?

[Dock, D. <dio...@me...>]

From: Dongsheng Song [mailto:don...@gm...] 
Sent: Wednesday, March 09, 2011 6:17 PM
To: Dock, Dion; Kai Tietz
Cc: min...@li...
Subject: Re: [Mingw-w64-public] why aren't "secure" _s functions provided?

On Thu, Mar 10, 2011 at 09:07, Dock, Dion <dio...@me...> wrote:
How did you do that?  nm isn't displaying those functions in my preferred runtime lib, libmsvcr80.a.  For example,
  C:\Temp>C:\mingw_32\bin\i686-w64-mingw32-nm.exe C:\mingw_32\mingw\lib\libmsvcr80.a | find "strcpy_s" 
  C:\Temp>

You can use gendef [1, 2] to generate .def file from .dll file.

[1] https://mingw-w64.svn.sourceforge.net/svnroot/mingw-w64/trunk/mingw-w64-tools/gendef
[2] http://i18n-zh.googlecode.com/files/gendef-r3706.exe
 

Thanks!  Adding the "-lmsvcr80" resolved a few of the symbols.  Now I've hit the next stumbling block: vsnprintf_s and localtime32_s.

These don't seem to be in libmsvcr80.a, but per the above, I'm not sure how to check for their presence.  Neither is a macro, however.
 
In  msvcr80.dll, here is thess function names list:

_localtime32_s
_vsnprintf_s
_vsnprintf_s_l
strcpy_s

So you must use vsnprintf_s and localtime32_s with prefix '_', as ms vc declared:
_CRTIMP errno_t __cdecl _localtime32_s(_Out_ struct tm *_Tm, _In_ const __time32_t * _Time);
_Check_return_opt_ _CRTIMP_ALTERNATIVE int __cdecl _vsnprintf_s(_Out_z_cap_(_SizeInBytes) char * _DstBuf, _In_ size_t _SizeInBytes, _In_ size_t _MaxCount, _In_z_ _Printf_format_string_ const char * _Format, va_list _ArgList);

But in the w64 repository, no such symbols:

$ grep -E "vsnprintf|localtime" msvcr80.def
_vsnprintf
localtime DATA
;_localtime32 = localtime
_localtime64

So you must add these symbols yourself, then rebuild libmsvcr80.a; or you can simply copy msvcr80.dll to libmsvcr80.a.

@Kai, could you rebuild msvcr*.def from msvcr*.dll ?

--
Dongsheng


I'm still flailing around with this.

C:\Temp>more dion.c
#include <stdio.h>
#include <time.h>

int main()
{
   struct tm aTm;
   int err = 0;
   __time32_t time;

   _time32(&time);
   err = _localtime32_s(&aTm, &time);

   return 0;
}

DION: defaults don't work
C:\Temp>C:\mingw_32\bin\i686-w64-mingw32-gcc.exe dion.c
C:\Users\dockd\AppData\Local\Temp\ccoRa8Cv.o:dion.c:(.text+0x3a): undefined reference to `_localtime32_s'
collect2: ld returned 1 exit status

DION: try the VS 2005 version of the C runtime
C:\Temp>C:\mingw_32\bin\i686-w64-mingw32-gcc.exe dion.c -lmsvcr80
C:\Users\dockd\AppData\Local\Temp\cckwwBoL.o:dion.c:(.text+0x3a): undefined reference to `_localtime32_s'
collect2: ld returned 1 exit status

DION: try creating my own version of the C runtime
C:\Temp>C:\mingw_32\bin\i686-w64-mingw32-dlltool.exe -D "C:\Program Files (x86)\
Microsoft Visual Studio 8\VC\redist\x86\Microsoft.VC80.CRT\msvcr80.dll" -d msvcr80.def -l libmsvcr80.a
C:\mingw_32\bin\i686-w64-mingw32-dlltool.exe: Path components stripped from dllname, 'C:\Program Files (x86)\Microsoft Visual Studio 8\VC\redist\x86\Microsoft.VC80.CRT\msvcm80.dll'.

C:\Temp>C:\mingw_32\bin\i686-w64-mingw32-gcc.exe dion.c libmsvcr80.a
c:/mingw_32/bin/../lib/gcc/i686-w64-mingw32/4.5.2/../../../../i686-w64-mingw32/lib/libmingw32.a(lib32_libmingw32_a-mingw_helpers.o): In function `encode_pointer':
c:\bb\vista64-mingw32\mingw-x86-x86\build\build\mingw\obj/../../../build/mingw/mingw-w64-crt/crt/mingw_helpers.c:26: multiple definition of `_encode_pointer'
libmsvcr80.a(dqmlfs00370.o):(.text+0x0): first defined here
collect2: ld returned 1 exit status

suggestions?
-Dion