[pacman-dev] [PATCH] package.c, fix incorrect buffersize

[Allan McRae]

On 01/11/15 10:32, Rikard Falkeborn wrote:
> Correct title_suffix_len to be the actual number of elements in
> the string (including the NUL-terminator) instead of the size
> of a pointer.
> 
> Note that wmemcpy blindly copies the number of wide characters it is told
> to copy (no check for NUL-terminating character), so this previously copied
> data outside of title_suffix.
> 

This is actually not the cause of the warning from clang...   But it
does fix it (unlike all the other suggestions in the thread).


package.c:95:34: error: variable length array folded to constant array as an
      extension [-Werror,-Wgnu-folding-constant]
        wchar_t wbuf[ARRAYSIZE(titles)][TITLE_MAXLEN + title_suffix_len];
                                        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
package.c:81:22: note: expanded from macro 'TITLE_MAXLEN'
#define TITLE_MAXLEN 50
                     ^



> Signed-off-by: Rikard Falkeborn <rikard.falkeborn at gmail.com>
> ---
>  src/pacman/package.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/src/pacman/package.c b/src/pacman/package.c
> index dbd23f5..59f4327 100644
> --- a/src/pacman/package.c
> +++ b/src/pacman/package.c
> @@ -79,6 +79,8 @@ enum {
>   * potential growth.
>   */
>  #define TITLE_MAXLEN 50
> +#define TITLE_SUFFIX L" :"
> +#define TITLE_SUFFIX_LEN (ARRAYSIZE(TITLE_SUFFIX))
>  
>  static char titles[_T_MAX][TITLE_MAXLEN * sizeof(wchar_t)];
>  
> @@ -90,9 +92,7 @@ static void make_aligned_titles(void)
>  {
>  	unsigned int i;
>  	size_t max = 0;
> -	static const wchar_t *title_suffix = L" :";
> -	static const size_t title_suffix_len = sizeof(title_suffix);
> -	wchar_t wbuf[ARRAYSIZE(titles)][TITLE_MAXLEN + title_suffix_len];
> +	wchar_t wbuf[ARRAYSIZE(titles)][TITLE_MAXLEN + TITLE_SUFFIX_LEN];
>  	size_t wlen[ARRAYSIZE(wbuf)];
>  	char *buf[ARRAYSIZE(wbuf)];
>  	buf[T_ARCHITECTURE] = _("Architecture");
> @@ -133,7 +133,7 @@ static void make_aligned_titles(void)
>  
>  	for(i = 0; i < ARRAYSIZE(wbuf); i++) {
>  		wmemset(wbuf[i] + wlen[i], L' ', max - wlen[i]);
> -		wmemcpy(wbuf[i] + max, title_suffix, title_suffix_len);
> +		wmemcpy(wbuf[i] + max, TITLE_SUFFIX, TITLE_SUFFIX_LEN);
>  		wcstombs(titles[i], wbuf[i], sizeof(wbuf[i]));
>  	}
>  }
>