Re: [ros-dev] [ros-diffs] [pschweitzer] 62675: [CHARMAP] Use rather wcsncpy(). A bit less safe, but at least, data are copied till possible

[Pierre Schweitzer]

Actually, it was based on my observation of:
http://doxygen.reactos.org/dc/d77/wcs_8c_afce6ecc002302f621f1280446ee5ae77.…
http://doxygen.reactos.org/d1/d60/tcsncpy_8h_source.html

My point was not to break program behavior by producing empty strings.
Actually, with current functions, I do. So that's an open question.

My (naive) guess, would be as I did on CDFS: copy len - 1 and 0 last char.

On 07/04/2014 00:08, Timo Kreuzer wrote:
>   I don't really see the reason here. Whether using
> the secure function or
>  not is is a question of whether we need null-termination or not.
>  If we need it the secure function will do the right thing. If we do not
>  need null-termination the non-secure function does the right thing and
>  the secure function would not add any security, but simply do the wrong
>  thing.
>  MSDN says about the lfFaceName member of the LOGFONT structure "A
>  null-terminated string that specifies the typeface name of the font. "
>  So we want it to be null-terminated and adding one more character does
>  not add anything useful, but will result in a broken structure.
>  Another difference is that the non-secure function pads the destination
>  array with nulls, the secure function does - afaik - not. If that is the
>  reason, I'd prefer zeroing it out before copying the string.
>
>  Am 06.04.2014 22:20, schrieb pschweitzer(a)svn.reactos.org:
> >   Author: pschweitzer
> >  Date: Sun Apr  6 20:20:39 2014
> >  New Revision: 62675
> >
> >  URL: http://svn.reactos.org/svn/reactos?rev=62675&view=rev
> >  Log:
> >  [CHARMAP]
> >  Use rather wcsncpy(). A bit less safe, but at least, data are copied till possible
> >
> >  Modified:
> >      trunk/reactos/base/applications/charmap/lrgcell.c
> >      trunk/reactos/base/applications/charmap/map.c
> >
> >  Modified: trunk/reactos/base/applications/charmap/lrgcell.c
> >  URL:
> > http://svn.reactos.org/svn/reactos/trunk/reactos/base/applications/charmap/…
> >  ==============================================================================
> >  --- trunk/reactos/base/applications/charmap/lrgcell.c	[iso-8859-1] (original)
> >  +++ trunk/reactos/base/applications/charmap/lrgcell.c	[iso-8859-1] Sun Apr  6 20:20:39
> > 2014
> >  @@ -48,9 +48,9 @@
> >                         hdc);
> >   
> >               lf.lfCharSet =  DEFAULT_CHARSET;
> >  -            wcscpy_s(lf.lfFaceName,
> >  -                     sizeof(lf.lfFaceName) / sizeof(lf.lfFaceName[0]),
> >  -                     lpFontName);
> >  +            wcsncpy(lf.lfFaceName,
> >  +                    lpFontName,
> >  +                    sizeof(lf.lfFaceName) / sizeof(lf.lfFaceName[0]));
> >   
> >               hFont = CreateFontIndirectW(&lf);
> >   
> >
> >  Modified: trunk/reactos/base/applications/charmap/map.c
> >  URL:
> > http://svn.reactos.org/svn/reactos/trunk/reactos/base/applications/charmap/…
> >  ==============================================================================
> >  --- trunk/reactos/base/applications/charmap/map.c	[iso-8859-1] (original)
> >  +++ trunk/reactos/base/applications/charmap/map.c	[iso-8859-1] Sun Apr  6 20:20:39 2014
> >  @@ -228,9 +228,9 @@
> >       ReleaseDC(infoPtr->hMapWnd, hdc);
> >   
> >       infoPtr->CurrentFont.lfCharSet =  DEFAULT_CHARSET;
> >  -    wcscpy_s(infoPtr->CurrentFont.lfFaceName,
> >  -             sizeof(infoPtr->CurrentFont.lfFaceName) /
> > sizeof(infoPtr->CurrentFont.lfFaceName[0]),
> >  -             lpFontName);
> >  +    wcsncpy(infoPtr->CurrentFont.lfFaceName,
> >  +            lpFontName,
> >  +            sizeof(infoPtr->CurrentFont.lfFaceName) /
> > sizeof(infoPtr->CurrentFont.lfFaceName[0]));
> >   
> >       infoPtr->hFont = CreateFontIndirectW(&infoPtr->CurrentFont);
> >   
> >
> >
> >  
>  _______________________________________________
>  Ros-dev mailing list
>  Ros-dev(a)reactos.org
>  http://www.reactos.org/mailman/listinfo/ros-dev 

-- 
Pierre Schweitzer<pierre at reactos.org>
System Administrator
ReactOS Foundation