[PATCH 2/2] user32/listbox: Optimize SetCount partly

[Huw Davies]

On Tue, Sep 18, 2018 at 11:15:58PM +0300, Gabriel Ivăncescu wrote:
> Signed-off-by: Gabriel Ivăncescu <gabrielopcode at gmail.com>
> ---
>  dlls/user32/listbox.c | 23 ++++++++++++++++++-----
>  1 file changed, 18 insertions(+), 5 deletions(-)
> 
> diff --git a/dlls/user32/listbox.c b/dlls/user32/listbox.c
> index c8bd148..a8de8d3 100644
> --- a/dlls/user32/listbox.c
> +++ b/dlls/user32/listbox.c
> @@ -1763,18 +1763,31 @@ static LRESULT LISTBOX_SetCount( LB_DESCR *descr, INT count )
>          return LB_ERR;
>      }
>  
> -    /* FIXME: this is far from optimal... */
>      if (count > descr->nb_items)
>      {
> -        while (count > descr->nb_items)
> -            if ((ret = LISTBOX_InsertString( descr, -1, 0 )) < 0)
> -                return ret;
> +        INT num = descr->nb_items;
> +        if ((ret = LISTBOX_InitStorage(descr, count - num)) != LB_OKAY)
> +            return ret;
> +        memset(&descr->items[num], 0, (count - num) * sizeof(*descr->items));
> +        descr->nb_items = count;
> +
> +        LISTBOX_UpdateScroll(descr);
> +        LISTBOX_InvalidateItems(descr, num);
> +
> +        /* If listbox was empty, set focus to the first item */
> +        if (count == 1) LISTBOX_SetCaretIndex(descr, 0, FALSE);

Shouldn't this be if (num == 0) ?  That would at least match the comment.

Huw.