[vlc-devel] [PATCH 4/5] win32: fix %zu fixups - dont use mingw's vsnprintf

[Cyril MATHE]

Hello,


	I just cross-compiled for win 32 with mingw and the compilation works
well. I test on windows XP SP2 and now VLC doesn't crash anymore.




Le jeudi 26 mars 2009 à 14:22 +0000, davidf+nntp at woaf.net a écrit :
> From: David Flynn <davidf at rd.bbc.co.uk>
> 
> Traditionally, MSVCRT has provided vsnprintf as _vsnprintf;
> to 'aid' portability/standards compliance, mingw provide a
> static version of [v]snprintf that is buggy.
> 
> The bug manifests as %lx is treated as a 64bit argument not
> 32bit, ie consumes two 32bit parameters.  if a %s were to
> follow a %lx, bad things can happen.
> 
> Solution: Be sure to use the MSVCRT version, at least it
> behaves as expected
> 
> Additionally, make it a bit more obvious when vlc wrappers
> are being called by other wrappers.
> 
> Signed-off-by: David Flynn <davidf at rd.bbc.co.uk>
> ---
>  include/vlc_fixups.h |   16 +++++++++++-----
>  1 files changed, 11 insertions(+), 5 deletions(-)
> 
> diff --git a/include/vlc_fixups.h b/include/vlc_fixups.h
> index 15172b2..02cf88c 100644
> --- a/include/vlc_fixups.h
> +++ b/include/vlc_fixups.h
> @@ -124,7 +124,11 @@ static inline int vlc_vsprintf (char *str, const char *format, va_list ap)
>  static inline int vlc_vsnprintf (char *str, size_t size, const char *format, va_list ap)
>  {
>      char *fmt = vlc_fix_format_string (format);
> -    int ret = vsnprintf (str, size, fmt ? fmt : format, ap);
> +    /* traditionally, MSVCRT has provided vsnprintf as _vsnprintf;
> +     * to 'aid' portability/standards compliance, mingw provides a
> +     * static version of vsnprintf that is buggy.  Be sure to use
> +     * MSVCRT version, at least it behaves as expected */
> +    int ret = _vsnprintf (str, size, fmt ? fmt : format, ap);
>      free (fmt);
>      return ret;
>  }
> @@ -135,7 +139,7 @@ static inline int vlc_printf (const char *format, ...)
>      va_list ap;
>      int ret;
>      va_start (ap, format);
> -    ret = vprintf (format, ap);
> +    ret = vlc_vprintf (format, ap);
>      va_end (ap);
>      return ret;
>  }
> @@ -146,7 +150,7 @@ static inline int vlc_fprintf (FILE *stream, const char *format, ...)
>      va_list ap;
>      int ret;
>      va_start (ap, format);
> -    ret = vfprintf (stream, format, ap);
> +    ret = vlc_vfprintf (stream, format, ap);
>      va_end (ap);
>      return ret;
>  }
> @@ -158,7 +162,7 @@ static inline int vlc_sprintf (char *str, const char *format, ...)
>      va_list ap;
>      int ret;
>      va_start (ap, format);
> -    ret = vsprintf (str, format, ap);
> +    ret = vlc_vsprintf (str, format, ap);
>      va_end (ap);
>      return ret;
>  }
> @@ -170,10 +174,12 @@ static inline int vlc_snprintf (char *str, size_t size, const char *format, ...)
>      va_list ap;
>      int ret;
>      va_start (ap, format);
> -    ret = vsnprintf (str, size, format, ap);
> +    ret = vlc_vsnprintf (str, size, format, ap);
>      va_end (ap);
>      return ret;
>  }
> +/* win32: snprintf must always be vlc_snprintf or _snprintf,
> + * see comment in vlc_vsnprintf */
>  # define snprintf vlc_snprintf
>  
>  /* Make sure we don't use flawed vasprintf or asprintf either */