Add heuristics to differentiate touchpads

Use libinput_device_config_tap_get_finger_count to determine whether
a pointer is a touchpad.

swaymsg is also updated to reflect the new touchpad type.

include/sway/input/input-manager.h

@@ -62,4 +62,6 @@ struct input_config *input_device_get_config(struct sway_input_device *device);
 
 char *input_device_get_identifier(struct wlr_input_device *device);
 
+const char *input_device_get_type(struct sway_input_device *device);
+
 #endif

sway/input/input-manager.c

@@ -71,6 +71,40 @@ char *input_device_get_identifier(struct wlr_input_device *device) {
 	return identifier;
 }
 
+static bool device_is_touchpad(struct sway_input_device *device) {
+	if (device->wlr_device->type != WLR_INPUT_DEVICE_POINTER ||
+			!wlr_input_device_is_libinput(device->wlr_device)) {
+		return false;
+	}
+
+	struct libinput_device *libinput_device =
+		wlr_libinput_get_device_handle(device->wlr_device);
+
+	return libinput_device_config_tap_get_finger_count(libinput_device) > 0;
+}
+
+const char *input_device_get_type(struct sway_input_device *device) {
+	switch (device->wlr_device->type) {
+	case WLR_INPUT_DEVICE_POINTER:
+		if (device_is_touchpad(device)) {
+			return "touchpad";
+		} else {
+			return "pointer";
+		}
+	case WLR_INPUT_DEVICE_KEYBOARD:
+		return "keyboard";
+	case WLR_INPUT_DEVICE_TOUCH:
+		return "touch";
+	case WLR_INPUT_DEVICE_TABLET_TOOL:
+		return "tablet_tool";
+	case WLR_INPUT_DEVICE_TABLET_PAD:
+		return "tablet_pad";
+	case WLR_INPUT_DEVICE_SWITCH:
+		return "switch";
+	}
+	return "unknown";
+}
+
 static struct sway_input_device *input_sway_device_from_wlr(
 		struct wlr_input_device *device) {
 	struct sway_input_device *input_device = NULL;

sway/ipc-json.c

@@ -85,24 +85,6 @@ static const char *ipc_json_output_transform_description(enum wl_output_transfor
 	return NULL;
 }
 
-static const char *ipc_json_device_type_description(struct sway_input_device *device) {
-	switch (device->wlr_device->type) {
-	case WLR_INPUT_DEVICE_POINTER:
-		return "pointer";
-	case WLR_INPUT_DEVICE_KEYBOARD:
-		return "keyboard";
-	case WLR_INPUT_DEVICE_SWITCH:
-		return "switch";
-	case WLR_INPUT_DEVICE_TOUCH:
-		return "touch";
-	case WLR_INPUT_DEVICE_TABLET_TOOL:
-		return "tablet_tool";
-	case WLR_INPUT_DEVICE_TABLET_PAD:
-		return "tablet_pad";
-	}
-	return "unknown";
-}
-
 json_object *ipc_json_get_version(void) {
 	int major = 0, minor = 0, patch = 0;
 	json_object *version = json_object_new_object();
@@ -819,7 +801,7 @@ json_object *ipc_json_describe_input(struct sway_input_device *device) {
 		json_object_new_int(device->wlr_device->product));
 	json_object_object_add(object, "type",
 		json_object_new_string(
-			ipc_json_device_type_description(device)));
+			input_device_get_type(device)));
 
 	if (device->wlr_device->type == WLR_INPUT_DEVICE_KEYBOARD) {
 		struct wlr_keyboard *keyboard = device->wlr_device->keyboard;

swaymsg/main.c

@@ -98,6 +98,7 @@ static const char *pretty_type_name(const char *name) {
 	} type_names[] = {
 		{ "keyboard", "Keyboard" },
 		{ "pointer", "Mouse" },
+		{ "touchpad", "Touchpad" },
 		{ "tablet_pad", "Tablet pad" },
 		{ "tablet_tool", "Tablet tool" },
 		{ "touch", "Touch" },