[PATCH master 3/3] common: boards: wolfvision: fix handling of overlays parameter

[Michael Riesch]

Hi all,

On 5/15/24 10:00, Michael Riesch wrote:
> If the char **overlays parameter to wolfvision_rk3568_detect_hw is NULL,
> the overlay file names are not collected.
> 
> If overlays points to a NULL pointer, it is initialized properly with
> an empty string. This is convenient as the call to
>     globalvar_set("of.overlay.filepattern", my_resulting_string);
> that usually follows actually resets the global filepattern variable
> from its default "*" to "". Thereby, a paradoxical situation in which no
> extensions are detected but all available overlays are applied (due to "*")
> is avoided.
> 
> Nevertheless, it is still possible to pass an existing string to this
> method and let the method append overlay file names.
> 
> Signed-off-by: Michael Riesch <michael.riesch at wolfvision.net>
> ---
>  common/boards/wolfvision/common.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/common/boards/wolfvision/common.c b/common/boards/wolfvision/common.c
> index f483918cec..6cb76250dd 100644
> --- a/common/boards/wolfvision/common.c
> +++ b/common/boards/wolfvision/common.c
> @@ -20,7 +20,7 @@ int wolfvision_apply_overlay(const struct wv_overlay *overlay, char **files)
>  {
>  	int ret;
>  
> -	if (overlay->filename) {
> +	if (overlay->filename && files) {
>  		if (*files) {
>  			char *old = *files;
>  			*files = basprintf("%s %s", old, overlay->filename);
> @@ -115,6 +115,9 @@ int wolfvision_rk3568_detect_hw(const struct wv_rk3568_extension *extensions,
>  	if (ret)
>  		return ret;
>  
> +	if (overlays && !*overlays)
> +		*overlays = basprintf("");

Hm, apparently this gives a compiler warning "warning: zero-length
gnu_printf format string [-Wformat-zero-length]".

... = basprintf("%s", ""); ???

Best regards,
Michael

> +
>  	for (i = 0; i < num_extensions; i++) {
>  		const struct wv_rk3568_extension *extension = &extensions[i];
>  		const struct wv_overlay *overlay;
>