[PATCH weston 2/3] clients: Require EGL_MIN_SWAP_INTERVAL to be 0 for subsurfaces

[Derek Foreman]

On 26/01/15 04:19 AM, Jonas Ådahl wrote:
> Warn and fail when trying to create sub surfaces when swap interval 0 is
> not supported by the EGL platform.
> 
> Signed-off-by: Jonas Ådahl <jadahl at gmail.com>
> ---
>  clients/nested.c      |  1 +
>  clients/subsurfaces.c |  2 ++
>  clients/window.c      | 19 +++++++++++++++++++
>  3 files changed, 22 insertions(+)
> 
> diff --git a/clients/nested.c b/clients/nested.c
> index f094237..696b727 100644
> --- a/clients/nested.c
> +++ b/clients/nested.c
> @@ -970,6 +970,7 @@ ss_surface_init(struct nested_surface *surface)
>  		window_add_subsurface(nested->window,
>  				      nested,
>  				      SUBSURFACE_SYNCHRONIZED);
> +	assert(ss_surface->widget);

Should we really be using assert() for these?

>  
>  	widget_set_use_cairo(ss_surface->widget, 0);
>  
> diff --git a/clients/subsurfaces.c b/clients/subsurfaces.c
> index 833030f..e0a5010 100644
> --- a/clients/subsurfaces.c
> +++ b/clients/subsurfaces.c
> @@ -500,6 +500,7 @@ triangle_create(struct window *window, struct egl_state *egl)
>  	tri->egl = egl;
>  	tri->widget = window_add_subsurface(window, tri,
>  		int_to_mode(option_triangle_mode));
> +	assert(tri->widget);
>  	widget_set_use_cairo(tri->widget, 0);
>  	widget_set_resize_handler(tri->widget, triangle_resize_handler);
>  	widget_set_redraw_handler(tri->widget, triangle_redraw_handler);
> @@ -737,6 +738,7 @@ demoapp_create(struct display *display)
>  
>  	app->subsurface = window_add_subsurface(app->window, app,
>  		int_to_mode(option_red_mode));
> +	assert(app->subsurface);
>  	widget_set_redraw_handler(app->subsurface, sub_redraw_handler);
>  	widget_set_resize_handler(app->subsurface, sub_resize_handler);
>  
> diff --git a/clients/window.c b/clients/window.c
> index b45b499..beb28ca 100644
> --- a/clients/window.c
> +++ b/clients/window.c
> @@ -2023,6 +2023,9 @@ window_create_tooltip(struct tooltip *tooltip)
>  
>  	tooltip->widget = window_add_subsurface(parent->window, tooltip, SUBSURFACE_DESYNCHRONIZED);
>  
> +	if (!tooltip->widget)
> +		return -1;
> +
>  	extents = get_text_extents(display, tooltip);
>  	widget_set_redraw_handler(tooltip->widget, tooltip_redraw_handler);
>  	widget_set_allocation(tooltip->widget,
> @@ -4844,6 +4847,22 @@ window_add_subsurface(struct window *window, void *data,
>  	struct surface *surface;
>  	struct wl_surface *parent;
>  	struct wl_subcompositor *subcompo = window->display->subcompositor;
> +	GLint min_swap_interval;
> +
> +	if (EGL_FALSE == eglGetConfigAttrib(window->display->dpy,
> +					    window->display->argb_config,
> +					    EGL_MIN_SWAP_INTERVAL,
> +					    &min_swap_interval)) {
> +		fprintf(stderr, "failed to add subsurface, couldn't retrieve "
> +			"EGL_MIN_SWAP_INTERVAL\n");
> +		return NULL;
> +	}
> +
> +	if (min_swap_interval > 0) {
> +		fprintf(stderr, "failed to add subsurface, no "
> +			"EGLSwapInterval(0) support\n");
> +		return NULL;
> +	}
>  
>  	surface = surface_create(window);
>  	surface->buffer_type = window_get_buffer_type(window);
>