From 1a9885aa52151dd239d6dea46e3c6890148e4d30 Mon Sep 17 00:00:00 2001
From: Simon Long <simon@raspberrypi.com>
Date: Fri, 26 Apr 2024 11:05:12 +0100
Subject: [PATCH] Only respond to modifier-only keybindings on release

---
 include/config/keybind.h |  1 +
 include/input/keyboard.h |  1 +
 src/config/keybind.c     |  3 +++
 src/input/keyboard.c     | 24 +++++++++++++++++-------
 4 files changed, 22 insertions(+), 7 deletions(-)

diff --git a/include/config/keybind.h b/include/config/keybind.h
index c61392aa..139442e5 100644
--- a/include/config/keybind.h
+++ b/include/config/keybind.h
@@ -20,6 +20,7 @@ struct keybind {
 	int keycodes_layout;
 	struct wl_list actions;  /* struct action.link */
 	struct wl_list link;     /* struct rcxml.keybinds */
+	bool mod_only;           /* set if only modifier keys used */
 };
 
 /**
diff --git a/include/input/keyboard.h b/include/input/keyboard.h
index ff4fbe60..c44d12b3 100644
--- a/include/input/keyboard.h
+++ b/include/input/keyboard.h
@@ -20,5 +20,6 @@ void keyboard_set_numlock(struct wlr_keyboard *keyboard);
 void keyboard_update_layout(struct seat *seat, xkb_layout_index_t layout);
 void keyboard_cancel_keybind_repeat(struct keyboard *keyboard);
 bool keyboard_any_modifiers_pressed(struct wlr_keyboard *keyboard);
+bool keyboard_is_modifier_key(xkb_keysym_t sym);
 
 #endif /* LABWC_KEYBOARD_H */
diff --git a/src/config/keybind.c b/src/config/keybind.c
index 1de02513..1b060cc5 100644
--- a/src/config/keybind.c
+++ b/src/config/keybind.c
@@ -10,6 +10,7 @@
 #include "common/mem.h"
 #include "config/keybind.h"
 #include "config/rcxml.h"
+#include "input/keyboard.h"
 #include "labwc.h"
 
 uint32_t
@@ -122,6 +123,7 @@ keybind_create(const char *keybind)
 	struct keybind *k = znew(*k);
 	xkb_keysym_t keysyms[MAX_KEYSYMS];
 	gchar **symnames = g_strsplit(keybind, "-", -1);
+	k->mod_only = TRUE;
 	for (size_t i = 0; symnames[i]; i++) {
 		char *symname = symnames[i];
 		uint32_t modifier = parse_modifier(symname);
@@ -129,6 +131,7 @@ keybind_create(const char *keybind)
 			k->modifiers |= modifier;
 		} else {
 			sym = xkb_keysym_from_name(symname, XKB_KEYSYM_CASE_INSENSITIVE);
+			if (!keyboard_is_modifier_key (sym)) k->mod_only = FALSE;
 			if (sym == XKB_KEY_NoSymbol && g_utf8_strlen(symname, -1) == 1) {
 				/*
 				 * xkb_keysym_from_name() only handles a legacy set of single
diff --git a/src/input/keyboard.c b/src/input/keyboard.c
index 59761681..46152590 100644
--- a/src/input/keyboard.c
+++ b/src/input/keyboard.c
@@ -38,6 +38,8 @@ struct keyinfo {
 
 static bool should_cancel_cycling_on_next_key_release;
 
+struct keybind *cur_keybind = NULL;
+
 static void
 change_vt(struct server *server, unsigned int vt)
 {
@@ -207,8 +209,8 @@ process_syms:
 	return NULL;
 }
 
-static bool
-is_modifier_key(xkb_keysym_t sym)
+bool
+keyboard_is_modifier_key(xkb_keysym_t sym)
 {
 	switch (sym) {
 	case XKB_KEY_Shift_L:   case XKB_KEY_Shift_R:
@@ -273,7 +275,7 @@ get_keyinfo(struct wlr_keyboard *wlr_keyboard, uint32_t evdev_keycode)
 	keyinfo.is_modifier = false;
 	for (int i = 0; i < keyinfo.translated.nr_syms; i++) {
 		keyinfo.is_modifier |=
-			is_modifier_key(keyinfo.translated.syms[i]);
+			keyboard_is_modifier_key(keyinfo.translated.syms[i]);
 	}
 
 	return keyinfo;
@@ -407,7 +409,14 @@ handle_compositor_keybindings(struct keyboard *keyboard,
 		keyinfo.is_modifier);
 
 	if (event->state == WL_KEYBOARD_KEY_STATE_RELEASED) {
-		return handle_key_release(server, event->keycode);
+		if (cur_keybind && cur_keybind->mod_only) {
+			key_state_store_pressed_key_as_bound(event->keycode);
+			actions_run(NULL, server, &cur_keybind->actions, 0);
+			cur_keybind = NULL;
+			return true;
+		} else {
+			return handle_key_release(server, event->keycode);
+		}
 	}
 
 	/* Catch C-A-F1 to C-A-F12 to change tty */
@@ -443,16 +452,17 @@ handle_compositor_keybindings(struct keyboard *keyboard,
 	/*
 	 * Handle compositor keybinds
 	 */
-	struct keybind *keybind =
+	cur_keybind =
 		match_keybinding(server, &keyinfo, keyboard->is_virtual);
-	if (keybind) {
+	if (cur_keybind && !cur_keybind->mod_only) {
 		/*
 		 * Update key-state before action_run() because the action
 		 * might lead to seat_focus() in which case we pass the
 		 * 'pressed-sent' keys to the new surface.
 		 */
 		key_state_store_pressed_key_as_bound(event->keycode);
-		actions_run(NULL, server, &keybind->actions, 0);
+		actions_run(NULL, server, &cur_keybind->actions, 0);
+		cur_keybind = NULL;
 		return true;
 	}