protocols: add generic output tracker

Follow-up patches will use the new generic output tracker for - ext-workspaces - cosmic-workspaces - ext-foreign-toplevel-info
2025-11-05 13:29:58 -05:00 · 2025-02-09 20:26:58 +01:00 · 2025-02-09 20:26:58 +01:00 · 46620d4fec
commit 46620d4fec
parent fb5e85f40f
3 changed files with 205 additions and 0 deletions
--- a/src/protocols/output-tracker.c
+++ b/src/protocols/output-tracker.c
@ -0,0 +1,178 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include <assert.h>
+#include <wlr/types/wlr_output.h>
+#include <wlr/util/log.h>
+#include "common/mem.h"
+#include "common/list.h"
+#include "protocols/output-tracker.h"
+
+struct object_output {
+	void *object;
+	struct wl_list *object_resources;
+	struct wlr_output *wlr_output;
+	const struct output_tracker_impl *impl;
+
+	struct {
+		struct wl_listener output_bind;
+		struct wl_listener output_destroy;
+	} on;
+	struct wl_list link;
+};
+
+static struct wl_list objects = WL_LIST_INIT(&objects);
+
+/* Internal helpers */
+static bool
+object_output_send_event(struct wl_list *object_resources, struct wl_list *output_resources,
+		void (*notifier)(struct wl_resource *object, struct wl_resource *output))
+{
+	bool sent = false;
+	struct wl_client *client;
+	struct wl_resource *object_resource, *output_resource;
+	wl_resource_for_each(object_resource, object_resources) {
+		client = wl_resource_get_client(object_resource);
+		wl_resource_for_each(output_resource, output_resources) {
+			if (wl_resource_get_client(output_resource) == client) {
+				notifier(object_resource, output_resource);
+				sent = true;
+			}
+		}
+	}
+	return sent;
+}
+
+static void
+_object_output_destroy(struct object_output *object_output)
+{
+	object_output_send_event(
+		object_output->object_resources,
+		&object_output->wlr_output->resources,
+		object_output->impl->send_output_leave);
+
+	wl_list_remove(&object_output->link);
+	wl_list_remove(&object_output->on.output_bind.link);
+	wl_list_remove(&object_output->on.output_destroy.link);
+
+	if (object_output->impl->send_done) {
+		object_output->impl->send_done(object_output->object, /*client*/ NULL);
+	}
+
+	free(object_output);
+}
+
+/* Internal handlers */
+static void
+handle_output_destroy(struct wl_listener *listener, void *data)
+{
+	struct object_output *object_output =
+		wl_container_of(listener, object_output, on.output_destroy);
+	_object_output_destroy(object_output);
+}
+
+static void
+handle_output_bind(struct wl_listener *listener, void *data)
+{
+	struct object_output *object_output =
+		wl_container_of(listener, object_output, on.output_bind);
+
+	struct wlr_output_event_bind *event = data;
+	struct wl_client *client = wl_resource_get_client(event->resource);
+
+	bool sent = false;
+	struct wl_resource *object_resource;
+	wl_resource_for_each(object_resource, object_output->object_resources) {
+		if (wl_resource_get_client(object_resource) == client) {
+			object_output->impl->send_output_enter(object_resource, event->resource);
+			sent = true;
+		}
+	}
+	if (!sent || !object_output->impl->send_done) {
+		return;
+	}
+
+	object_output->impl->send_done(object_output->object, client);
+}
+
+/* Public API */
+void
+output_tracker_send_initial_state_to_resource(void *object, struct wl_resource *object_resource)
+{
+	struct object_output *object_output;
+	struct wl_client *client = wl_resource_get_client(object_resource);
+	wl_list_for_each(object_output, &objects, link) {
+		if (object_output->object != object) {
+			continue;
+		}
+		struct wl_resource *output_resource;
+		wl_resource_for_each(output_resource, &object_output->wlr_output->resources) {
+			if (wl_resource_get_client(output_resource) != client) {
+				continue;
+			}
+			object_output->impl->send_output_enter(object_resource, output_resource);
+		}
+	}
+}
+
+void
+output_tracker_enter(void *object, struct wl_list *object_resources,
+		struct wlr_output *wlr_output, const struct output_tracker_impl *impl)
+{
+	assert(impl);
+	assert(impl->send_output_enter);
+	assert(impl->send_output_leave);
+	struct object_output *object_output;
+	wl_list_for_each(object_output, &objects, link) {
+		if (object_output->wlr_output == wlr_output
+				&& object_output->object == object) {
+			/* Object already on given output */
+			return;
+		}
+	}
+	object_output = znew(*object_output);
+	object_output->object = object;
+	object_output->object_resources = object_resources;
+	object_output->wlr_output = wlr_output;
+	object_output->impl = impl;
+
+	object_output->on.output_bind.notify = handle_output_bind;
+	wl_signal_add(&wlr_output->events.bind, &object_output->on.output_bind);
+
+	object_output->on.output_destroy.notify = handle_output_destroy;
+	wl_signal_add(&wlr_output->events.destroy, &object_output->on.output_destroy);
+
+	wl_list_insert(&objects, &object_output->link);
+
+	bool sent = object_output_send_event(
+		object_resources, &wlr_output->resources, impl->send_output_enter);
+
+	if (sent && impl->send_done) {
+		impl->send_done(object, /*client*/ NULL);
+	}
+}
+
+void
+output_tracker_destroy(void *object)
+{
+	struct object_output *object_output, *tmp;
+	wl_list_for_each_safe(object_output, tmp, &objects, link) {
+		if (object_output->object == object) {
+			_object_output_destroy(object_output);
+		}
+	}
+}
+
+void
+output_tracker_leave(void *object, struct wlr_output *wlr_output)
+{
+	struct object_output *tmp;
+	struct object_output *object_output = NULL;
+	wl_list_for_each(tmp, &objects, link) {
+		if (tmp->object == object && tmp->wlr_output == wlr_output) {
+			object_output = tmp;
+			break;
+		}
+	}
+	if (object_output) {
+		_object_output_destroy(object_output);
+	}
+}