commands/input: perform basic keymap validation

Before the delta input config is stored, this attempts to compile a
keymap with it. If the keymap fails to compile, then the first line of
the xkbcommon log entry will be included with a `CMD_FAILURE`, the
entire xkbcommon log entry will be included in the sway error log, and
the delta will not be stored.

This only handles basic issues such as a layouts not existing. This
will NOT catch more complex issues such as when a variant does
exist, but not for the given layout (ex: `azerty` is a valid variant,
but the `us` layout does not have a `azerty` variant).

1 files changed, 2 insertions, 1 deletions

diff --git a/include/sway/input/keyboard.h b/include/sway/input/keyboard.h
index b8622053..90214af9 100644
--- a/include/sway/input/keyboard.h
+++ b/include/sway/input/keyboard.h
@@ -65,7 +65,8 @@ struct sway_keyboard {
 	struct sway_binding *repeat_binding;
 };
 
-struct xkb_keymap *sway_keyboard_compile_keymap(struct input_config *ic);
+struct xkb_keymap *sway_keyboard_compile_keymap(struct input_config *ic,
+		char **error);
 
 struct sway_keyboard *sway_keyboard_create(struct sway_seat *seat,
 		struct sway_seat_device *device);