[PATCH weston 06/11] keyboard: Only set toplevel when there is a valid output

[Quentin Glidic]

On 18/06/2016 19:15, Armin Krezović wrote:
> Currently, the keyboard client is created and the input
> panel surface is set as toplevel on the first output it
> finds. This does not work in a scenario when there are
> no outputs, resulting in weston-keyboard to crash at
> startup due to operating on an invalid output pointer.
>
> This makes input panel toplevel setting depend on a
> valid output, and if there was no output present at
> startup, it will be set toplevel as soon as an output
> gets plugged in.
>
> Signed-off-by: Armin Krezović <krezovic.armin at gmail.com>
> ---

The overall idea is good, let’s see the details.


>  clients/keyboard.c | 33 +++++++++++++++++++++++++++------
>  1 file changed, 27 insertions(+), 6 deletions(-)
>
> diff --git a/clients/keyboard.c b/clients/keyboard.c
> index d719764..4fb4200 100644
> --- a/clients/keyboard.c
> +++ b/clients/keyboard.c
> @@ -24,6 +24,7 @@
>
>  #include "config.h"
>
> +#include <stdbool.h>
>  #include <stdio.h>
>  #include <stdlib.h>
>  #include <string.h>
> @@ -56,6 +57,7 @@ struct virtual_keyboard {
>  	char *surrounding_text;
>  	uint32_t surrounding_cursor;
>  	struct keyboard *keyboard;
> +	bool toplevel;
>  };
>
>  enum key_type {
> @@ -953,11 +955,26 @@ global_handler(struct display *display, uint32_t name,
>  }
>
>  static void
> +set_toplevel(struct output *output, struct virtual_keyboard *virtual_keyboard)
> +{
> +	struct zwp_input_panel_surface_v1 *ips;
> +	struct keyboard *keyboard = virtual_keyboard->keyboard;
> +
> +	ips = zwp_input_panel_v1_get_input_panel_surface(virtual_keyboard->input_panel,
> +							 window_get_wl_surface(keyboard->window));
> +
> +	zwp_input_panel_surface_v1_set_toplevel(ips,
> +						output_get_wl_output(output),
> +						ZWP_INPUT_PANEL_SURFACE_V1_POSITION_CENTER_BOTTOM);
> +
> +	virtual_keyboard->toplevel = true;
> +}
> +
> +static void
>  keyboard_create(struct output *output, struct virtual_keyboard *virtual_keyboard)
>  {
>  	struct keyboard *keyboard;
>  	const struct layout *layout;
> -	struct zwp_input_panel_surface_v1 *ips;
>
>  	layout = get_current_layout(virtual_keyboard);
>
> @@ -981,13 +998,16 @@ keyboard_create(struct output *output, struct virtual_keyboard *virtual_keyboard
>  			       layout->columns * key_width,
>  			       layout->rows * key_height);
>
> +	if (output)
> +		set_toplevel(output, virtual_keyboard);

I would drop it completely from here, see below.


> +}
>
> -	ips = zwp_input_panel_v1_get_input_panel_surface(virtual_keyboard->input_panel,
> -							 window_get_wl_surface(keyboard->window));
> +static
> +void display_output_handler(struct output *output, void *data) {
> +	struct virtual_keyboard *keyboard = data;
>
> -	zwp_input_panel_surface_v1_set_toplevel(ips,
> -						output_get_wl_output(output),
> -						ZWP_INPUT_PANEL_SURFACE_V1_POSITION_CENTER_BOTTOM);
> +	if (!keyboard->toplevel)
> +		set_toplevel(output, keyboard);
>  }
>
>  int
> @@ -1006,6 +1026,7 @@ main(int argc, char *argv[])
>
>  	display_set_user_data(virtual_keyboard.display, &virtual_keyboard);
>  	display_set_global_handler(virtual_keyboard.display, global_handler);
> +	display_set_output_configure_handler(virtual_keyboard.display, display_output_handler);

Is that handler called only on hotplug or is it called at startup too?
IOW, could we rely on it to be called at least one?


>
>  	if (virtual_keyboard.input_panel == NULL) {
>  		fprintf(stderr, "No input panel global\n");
>


Later in this file, there is:
	output = display_get_output(virtual_keyboard.display);
	keyboard_create(output, &virtual_keyboard);

Could be replaced by:
	keyboard_create(&virtual_keyboard);
	output = display_get_output(virtual_keyboard.display);
	if (output)
		set_toplevel(output, keyboard);

Or keyboard_create only if the handler is assured to be called at least 
once.

Anyone has comments? :-)

Cheers,

-- 

Quentin “Sardem FF7” Glidic