fix(keymap): Fix overflow in get/set bindings

With the binding referenced to as uint8_t the keymap would be incorrect if more than 256 positions were in use, going to a uint16_t gives large enough headroom to not have to worry

Author: ReFil

app/include/zmk/keymap.h

@@ -55,8 +55,8 @@ int zmk_keymap_layer_to(zmk_keymap_layer_id_t layer, bool locking);
 const char *zmk_keymap_layer_name(zmk_keymap_layer_id_t layer);
 
 const struct zmk_behavior_binding *zmk_keymap_get_layer_binding_at_idx(zmk_keymap_layer_id_t layer,
-                                                                       uint8_t binding_idx);
-int zmk_keymap_set_layer_binding_at_idx(zmk_keymap_layer_id_t layer, uint8_t binding_idx,
+                                                                       uint16_t binding_idx);
+int zmk_keymap_set_layer_binding_at_idx(zmk_keymap_layer_id_t layer, uint16_t binding_idx,
                                         const struct zmk_behavior_binding binding);
 
 #if IS_ENABLED(CONFIG_ZMK_KEYMAP_LAYER_REORDERING)

app/src/keymap.c

@@ -242,7 +242,7 @@ const char *zmk_keymap_layer_name(zmk_keymap_layer_id_t layer_id) {
 }
 
 const struct zmk_behavior_binding *
-zmk_keymap_get_layer_binding_at_idx(zmk_keymap_layer_id_t layer_id, uint8_t binding_idx) {
+zmk_keymap_get_layer_binding_at_idx(zmk_keymap_layer_id_t layer_id, uint16_t binding_idx) {
     if (binding_idx >= ZMK_KEYMAP_LEN) {
         return NULL;
     }
@@ -277,7 +277,7 @@ zmk_keymap_get_layer_binding_at_idx(zmk_keymap_layer_id_t layer_id, uint8_t bind
 
 static uint8_t zmk_keymap_layer_pending_changes[ZMK_KEYMAP_LAYERS_LEN][PENDING_ARRAY_SIZE];
 
-int zmk_keymap_set_layer_binding_at_idx(zmk_keymap_layer_id_t layer_id, uint8_t binding_idx,
+int zmk_keymap_set_layer_binding_at_idx(zmk_keymap_layer_id_t layer_id, uint16_t binding_idx,
                                         struct zmk_behavior_binding binding) {
     if (binding_idx >= ZMK_KEYMAP_LEN) {
         return -EINVAL;
@@ -322,7 +322,7 @@ int zmk_keymap_set_layer_binding_at_idx(zmk_keymap_layer_id_t layer_id, uint8_t
 
 #else
 
-int zmk_keymap_set_layer_binding_at_idx(zmk_keymap_layer_id_t layer_id, uint8_t binding_idx,
+int zmk_keymap_set_layer_binding_at_idx(zmk_keymap_layer_id_t layer_id, uint16_t binding_idx,
                                         struct zmk_behavior_binding binding) {
     return -ENOTSUP;
 }
@@ -631,8 +631,8 @@ static int keymap_track_changed_bindings(const char *key, size_t len, settings_r
                                          void *cb_arg, void *param) {
     const char *next;
     if (settings_name_steq(key, "l", &next) && next) {
-        uint8_t(*state)[ZMK_KEYMAP_LAYERS_LEN][PENDING_ARRAY_SIZE] =
-            (uint8_t(*)[ZMK_KEYMAP_LAYERS_LEN][PENDING_ARRAY_SIZE])param;
+        uint8_t (*state)[ZMK_KEYMAP_LAYERS_LEN][PENDING_ARRAY_SIZE] =
+            (uint8_t (*)[ZMK_KEYMAP_LAYERS_LEN][PENDING_ARRAY_SIZE])param;
         char *endptr;
         uint8_t layer = strtoul(next, &endptr, 10);
         if (*endptr != '/') {