config: support libinput sendEventsMode

This allows to enable / disable libinput devices.

Co-Authored-By: @Consolatis

docs/labwc-config.5.scd

@@ -684,6 +684,20 @@ extending outward from the snapped edge.
 
 	The default method depends on the touchpad hardware.
 
+*<libinput><device><sendEventsMode>* [yes|no|disabledOnExternalMouse]
+	Optionally enable or disable sending any device events.
+
+	The options available are:
+	- *yes* - Events are sent as usual
+	- *no* - No events are sent from this device
+	- *disabledOnExternalMouse* - This device does not send events if an
+	  external mouse has been detected.
+
+	It is possible to prevent events from a device in the config and then do
+	a Reconfigure to temporarily enable / disable specific devices.
+
+	By default, this setting is not configured.
+
 ## WINDOW RULES
 
 Two types of window rules are supported, actions and properties. They are

docs/rc.xml.all

@@ -473,6 +473,7 @@
       - accelProfile [flat|adaptive]
       - tapButtonMap [lrm|lmr]
       - clickMethod [none|buttonAreas|clickfinger]
+      - sendEventsMode [yes|no|disabledOnExternalMouse]
   -->
   <libinput>
     <device category="default">
@@ -487,6 +488,7 @@
       <middleEmulation></middleEmulation>
       <disableWhileTyping></disableWhileTyping>
       <clickMethod></clickMethod>
+      <sendEventsMode></sendEventsMode>
     </device>
   </libinput>
 

include/config/libinput.h

@@ -23,12 +23,13 @@ struct libinput_category {
 	int left_handed;
 	enum libinput_config_tap_state tap;
 	enum libinput_config_tap_button_map tap_button_map;
-	int tap_and_drag; /* -1 or libinput_config_drag_state */
+	int tap_and_drag;     /* -1 or libinput_config_drag_state */
-	int drag_lock; /* -1 or libinput_config_drag_lock_state */
+	int drag_lock;        /* -1 or libinput_config_drag_lock_state */
-	int accel_profile; /* -1 or libinput_config_accel_profile */
+	int accel_profile;    /* -1 or libinput_config_accel_profile */
-	int middle_emu; /* -1 or libinput_config_middle_emulation_state */
+	int middle_emu;       /* -1 or libinput_config_middle_emulation_state */
-	int dwt; /* -1 or libinput_config_dwt_state */
+	int dwt;              /* -1 or libinput_config_dwt_state */
-	int click_method; /* -1 or libinput_config_click_method */
+	int click_method;     /* -1 or libinput_config_click_method */
+	int send_events_mode; /* -1 or libinput_config_send_events_mode */
 };
 
 enum lab_libinput_device_type get_device_type(const char *s);

src/config/libinput.c

@@ -24,6 +24,7 @@ libinput_category_init(struct libinput_category *l)
 	l->middle_emu = -1;
 	l->dwt = -1;
 	l->click_method = -1;
+	l->send_events_mode = -1;
 }
 
 enum lab_libinput_device_type

src/config/rcxml.c

@@ -461,6 +461,29 @@ get_accel_profile(const char *s)
 	return -1;
 }
 
+static int
+get_send_events_mode(const char *s)
+{
+	if (!s) {
+		goto err;
+	}
+
+	int ret = parse_bool(s, -1);
+	if (ret >= 0) {
+		return ret
+			? LIBINPUT_CONFIG_SEND_EVENTS_ENABLED
+			: LIBINPUT_CONFIG_SEND_EVENTS_DISABLED;
+	}
+
+	if (!strcasecmp(s, "disabledOnExternalMouse")) {
+		return LIBINPUT_CONFIG_SEND_EVENTS_DISABLED_ON_EXTERNAL_MOUSE;
+	}
+
+err:
+	wlr_log(WLR_INFO, "Not a recognised send events mode");
+	return -1;
+}
+
 static void
 fill_libinput_category(char *nodename, char *content)
 {
@@ -576,6 +599,9 @@ fill_libinput_category(char *nodename, char *content)
 		} else {
 			wlr_log(WLR_ERROR, "invalid clickMethod");
 		}
+	} else if (!strcasecmp(nodename, "sendEventsMode")) {
+		current_libinput_category->send_events_mode =
+			get_send_events_mode(content);
 	}
 }
 

src/seat.c

@@ -91,6 +91,24 @@ get_category(struct wlr_input_device *device)
 static void
 configure_libinput(struct wlr_input_device *wlr_input_device)
 {
+	/*
+	 * TODO: We do not check any return values for the various
+	 *       libinput_device_config_*_set_*() calls. It would
+	 *       be nice if we could inform the users via log file
+	 *       that some libinput setting could not be applied.
+	 *
+	 * TODO: We are currently using int32_t with -1 as default
+	 *       to desribe the not-configured state. This is not
+	 *       really optimal as we can't properly deal with
+	 *       enum values that are 0. After some discussion via
+	 *       IRC the best way forward seem to be to use a
+	 *       uint32_t instead and UINT32_MAX as indicator for
+	 *       a not-configured state. This allows to properly
+	 *       test the enum being a member of a bitset via
+	 *       mask & value == value. All libinput enums are
+	 *       way below UINT32_MAX.
+	 */
+
 	if (!wlr_input_device) {
 		wlr_log(WLR_ERROR, "no wlr_input_device");
 		return;
@@ -209,6 +227,16 @@ configure_libinput(struct wlr_input_device *wlr_input_device)
 
 		libinput_device_config_click_set_method(libinput_dev, dc->click_method);
 	}
+
+	if ((dc->send_events_mode != LIBINPUT_CONFIG_SEND_EVENTS_ENABLED
+			&& (libinput_device_config_send_events_get_modes(libinput_dev)
+				& dc->send_events_mode) == 0)
+			|| dc->send_events_mode < 0) {
+		wlr_log(WLR_INFO, "send events mode not configured");
+	} else {
+		wlr_log(WLR_INFO, "send events mode configured");
+		libinput_device_config_send_events_set_mode(libinput_dev, dc->send_events_mode);
+	}
 }
 
 static struct wlr_output *