ext-foreign-toplevel-list-v1: new protocol implementation

This implements the new ext-foreign-toplevel-list-v1 protocol [1].
Implemented analog to the zwlr-foreign-toplevel-management-v1 implementation.
The additional _ext_ in the names was added to avoid name collisions.

[1]: https://gitlab.freedesktop.org/wayland/wayland-protocols/-/merge_requests/187

Co-authored-by: Leon Henrik Plickat <leonhenrik.plickat@stud.uni-goettingen.de>

4 files changed, 344 insertions, 0 deletions

diff --git a/include/wlr/types/wlr_ext_foreign_toplevel_list_v1.h b/include/wlr/types/wlr_ext_foreign_toplevel_list_v1.h
new file mode 100644
index 00000000..a5ba9d38
--- /dev/null
+++ b/include/wlr/types/wlr_ext_foreign_toplevel_list_v1.h
@@ -0,0 +1,67 @@
+/*
+ * This an unstable interface of wlroots. No guarantees are made regarding the
+ * future consistency of this API.
+ */
+#ifndef WLR_USE_UNSTABLE
+#error "Add -DWLR_USE_UNSTABLE to enable unstable wlroots features"
+#endif
+
+#ifndef WLR_TYPES_WLR_FOREIGN_TOPLEVEL_LIST_V1_H
+#define WLR_TYPES_WLR_FOREIGN_TOPLEVEL_LIST_V1_H
+
+#include <wayland-server-core.h>
+
+struct wlr_ext_foreign_toplevel_list_v1 {
+	struct wl_global *global;
+	struct wl_list resources; // wl_resource_get_link()
+	struct wl_list toplevels; // ext_foreign_toplevel_handle_v1.link
+
+	struct wl_listener display_destroy;
+
+	struct {
+		struct wl_signal destroy;
+	} events;
+
+	void *data;
+};
+
+struct wlr_ext_foreign_toplevel_handle_v1 {
+	struct wlr_ext_foreign_toplevel_list_v1 *list;
+	struct wl_list resources; // wl_resource_get_link()
+	struct wl_list link; // wlr_ext_foreign_toplevel_list_v1.toplevels
+
+	char *title;
+	char *app_id;
+	char *identifier;
+
+	struct {
+		struct wl_signal destroy;
+	} events;
+
+	void *data;
+};
+
+struct wlr_ext_foreign_toplevel_handle_v1_state {
+	const char *title;
+	const char *app_id;
+};
+
+struct wlr_ext_foreign_toplevel_list_v1 *wlr_ext_foreign_toplevel_list_v1_create(
+	struct wl_display *display, uint32_t version);
+
+struct wlr_ext_foreign_toplevel_handle_v1 *wlr_ext_foreign_toplevel_handle_v1_create(
+	struct wlr_ext_foreign_toplevel_list_v1 *list,
+	const struct wlr_ext_foreign_toplevel_handle_v1_state *state);
+
+/**
+ * Destroy the given toplevel handle, sending the closed event to any
+ * client.
+ */
+void wlr_ext_foreign_toplevel_handle_v1_destroy(
+	struct wlr_ext_foreign_toplevel_handle_v1 *toplevel);
+
+void wlr_ext_foreign_toplevel_handle_v1_update_state(
+	struct wlr_ext_foreign_toplevel_handle_v1 *toplevel,
+	const struct wlr_ext_foreign_toplevel_handle_v1_state *state);
+
+#endif
diff --git a/protocol/meson.build b/protocol/meson.build
index d8e93d62..6a8d82b4 100644
--- a/protocol/meson.build
+++ b/protocol/meson.build
@@ -22,6 +22,7 @@ protocols = {
 	'content-type-v1': wl_protocol_dir / 'staging/content-type/content-type-v1.xml',
 	'cursor-shape-v1': wl_protocol_dir / 'staging/cursor-shape/cursor-shape-v1.xml',
 	'drm-lease-v1': wl_protocol_dir / 'staging/drm-lease/drm-lease-v1.xml',
+	'ext-foreign-toplevel-list-v1': wl_protocol_dir / 'staging/ext-foreign-toplevel-list/ext-foreign-toplevel-list-v1.xml',
 	'ext-idle-notify-v1': wl_protocol_dir / 'staging/ext-idle-notify/ext-idle-notify-v1.xml',
 	'ext-session-lock-v1': wl_protocol_dir / 'staging/ext-session-lock/ext-session-lock-v1.xml',
 	'fractional-scale-v1': wl_protocol_dir / 'staging/fractional-scale/fractional-scale-v1.xml',
diff --git a/types/meson.build b/types/meson.build
index 688ddece..8962a390 100644
--- a/types/meson.build
+++ b/types/meson.build
@@ -42,6 +42,7 @@ wlr_files += files(
 	'wlr_drm.c',
 	'wlr_export_dmabuf_v1.c',
 	'wlr_foreign_toplevel_management_v1.c',
+	'wlr_ext_foreign_toplevel_list_v1.c',
 	'wlr_fullscreen_shell_v1.c',
 	'wlr_gamma_control_v1.c',
 	'wlr_idle_inhibit_v1.c',
diff --git a/types/wlr_ext_foreign_toplevel_list_v1.c b/types/wlr_ext_foreign_toplevel_list_v1.c
new file mode 100644
index 00000000..326e4f41
--- /dev/null
+++ b/types/wlr_ext_foreign_toplevel_list_v1.c
@@ -0,0 +1,275 @@
+#define _POSIX_C_SOURCE 200809L
+
+#include <assert.h>
+#include <string.h>
+#include <stdlib.h>
+#include <wlr/types/wlr_compositor.h>
+#include <wlr/types/wlr_ext_foreign_toplevel_list_v1.h>
+#include <wlr/types/wlr_seat.h>
+#include <wlr/util/log.h>
+#include "ext-foreign-toplevel-list-v1-protocol.h"
+
+#include "util/token.h"
+
+#define FOREIGN_TOPLEVEL_LIST_V1_VERSION 1
+
+static const struct ext_foreign_toplevel_list_v1_interface toplevel_handle_impl;
+
+static void foreign_toplevel_handle_destroy(struct wl_client *client,
+		struct wl_resource *resource) {
+	wl_resource_destroy(resource);
+}
+
+static const struct ext_foreign_toplevel_list_v1_interface toplevel_handle_impl = {
+	.destroy = foreign_toplevel_handle_destroy,
+};
+
+void wlr_ext_foreign_toplevel_handle_v1_update_state(
+		struct wlr_ext_foreign_toplevel_handle_v1 *toplevel,
+		const struct wlr_ext_foreign_toplevel_handle_v1_state *state) {
+	bool changed_app_id = false;
+	bool changed_title = false;
+
+	if (state->app_id) {
+		if (strcmp(toplevel->app_id, state->app_id) != 0) {
+			free(toplevel->app_id);
+			toplevel->app_id = strdup(state->app_id);
+			if (toplevel->app_id == NULL) {
+				wlr_log(WLR_ERROR, "failed to allocate memory for toplevel app_id");
+				return;
+			}
+			changed_app_id = true;
+		}
+	} else {
+		if (toplevel->app_id) {
+			free(toplevel->app_id);
+			toplevel->app_id = NULL;
+			changed_app_id = true;
+		}
+	}
+
+	if (state->title) {
+		if (strcmp(toplevel->title, state->title) != 0) {
+			free(toplevel->title);
+			toplevel->title = strdup(state->title);
+			if (toplevel->title == NULL) {
+				wlr_log(WLR_ERROR, "failed to allocate memory for toplevel title");
+				return;
+			}
+			changed_title = true;
+		}
+	} else {
+		if (toplevel->title) {
+			free(toplevel->title);
+			toplevel->title = NULL;
+			changed_title = true;
+		}
+	}
+
+	if (!changed_app_id && !changed_title) {
+		return;
+	}
+
+	struct wl_resource *resource;
+	wl_resource_for_each(resource, &toplevel->resources) {
+		if (changed_app_id) {
+			ext_foreign_toplevel_handle_v1_send_app_id(resource, state->app_id ? state->app_id : "");
+		}
+		if (changed_title) {
+			ext_foreign_toplevel_handle_v1_send_title(resource, state->title ? state->title : "");
+		}
+		ext_foreign_toplevel_handle_v1_send_done(resource);
+	}
+}
+
+void wlr_ext_foreign_toplevel_handle_v1_destroy(
+		struct wlr_ext_foreign_toplevel_handle_v1 *toplevel) {
+	if (!toplevel) {
+		return;
+	}
+
+	wl_signal_emit_mutable(&toplevel->events.destroy, NULL);
+
+	struct wl_resource *resource, *tmp;
+	wl_resource_for_each_safe(resource, tmp, &toplevel->resources) {
+		ext_foreign_toplevel_handle_v1_send_closed(resource);
+		wl_resource_set_user_data(resource, NULL);
+		wl_list_remove(wl_resource_get_link(resource));
+		wl_list_init(wl_resource_get_link(resource));
+	}
+
+	wl_list_remove(&toplevel->link);
+
+	free(toplevel->title);
+	free(toplevel->app_id);
+	free(toplevel->identifier);
+	free(toplevel);
+}
+
+static void foreign_toplevel_resource_destroy(struct wl_resource *resource) {
+	wl_list_remove(wl_resource_get_link(resource));
+}
+
+static struct wl_resource *create_toplevel_resource_for_resource(
+		struct wlr_ext_foreign_toplevel_handle_v1 *toplevel,
+		struct wl_resource *list_resource) {
+	struct wl_client *client = wl_resource_get_client(list_resource);
+	struct wl_resource *resource = wl_resource_create(client,
+			&ext_foreign_toplevel_handle_v1_interface,
+			wl_resource_get_version(list_resource), 0);
+	if (!resource) {
+		wl_client_post_no_memory(client);
+		return NULL;
+	}
+
+	wl_resource_set_implementation(resource, &toplevel_handle_impl, toplevel,
+		foreign_toplevel_resource_destroy);
+
+	wl_list_insert(&toplevel->resources, wl_resource_get_link(resource));
+	ext_foreign_toplevel_list_v1_send_toplevel(list_resource, resource);
+	return resource;
+}
+
+static void toplevel_send_details_to_toplevel_resource(
+		struct wlr_ext_foreign_toplevel_handle_v1 *toplevel,
+		struct wl_resource *resource) {
+	if (toplevel->title) {
+		ext_foreign_toplevel_handle_v1_send_title(resource, toplevel->title);
+	}
+	if (toplevel->app_id) {
+		ext_foreign_toplevel_handle_v1_send_app_id(resource, toplevel->app_id);
+	}
+	assert(toplevel->identifier); // Required to exist by protocol.
+	ext_foreign_toplevel_handle_v1_send_identifier(resource, toplevel->identifier);
+	ext_foreign_toplevel_handle_v1_send_done(resource);
+}
+
+struct wlr_ext_foreign_toplevel_handle_v1 *
+wlr_ext_foreign_toplevel_handle_v1_create(struct wlr_ext_foreign_toplevel_list_v1 *list,
+		const struct wlr_ext_foreign_toplevel_handle_v1_state *state) {
+	struct wlr_ext_foreign_toplevel_handle_v1 *toplevel = calloc(1, sizeof(*toplevel));
+	if (!toplevel) {
+		wlr_log(WLR_ERROR, "failed to allocate memory for toplevel handle");
+		return NULL;
+	}
+
+	toplevel->identifier = calloc(TOKEN_SIZE, sizeof(char));
+	if (toplevel->identifier == NULL) {
+		wlr_log(WLR_ERROR, "failed to allocate memory for toplevel identifier");
+		free(toplevel);
+		return NULL;
+	}
+
+	if (!generate_token(toplevel->identifier)) {
+		free(toplevel->identifier);
+		free(toplevel);
+		return NULL;
+	}
+
+	wl_list_insert(&list->toplevels, &toplevel->link);
+	toplevel->list = list;
+	if (state->app_id) {
+		toplevel->app_id = strdup(state->app_id);
+	}
+	if (state->title) {
+		toplevel->title = strdup(state->title);
+	}
+
+	wl_list_init(&toplevel->resources);
+
+	wl_signal_init(&toplevel->events.destroy);
+
+	struct wl_resource *list_resource, *toplevel_resource;
+	wl_resource_for_each(list_resource, &list->resources) {
+		toplevel_resource = create_toplevel_resource_for_resource(toplevel, list_resource);
+		if (!toplevel_resource) {
+			continue;
+		}
+		toplevel_send_details_to_toplevel_resource(toplevel, toplevel_resource);
+	}
+
+	return toplevel;
+}
+
+static const struct ext_foreign_toplevel_list_v1_interface
+	foreign_toplevel_list_impl;
+
+static void foreign_toplevel_list_handle_stop(struct wl_client *client,
+		struct wl_resource *resource) {
+	assert(wl_resource_instance_of(resource,
+		&ext_foreign_toplevel_list_v1_interface,
+		&foreign_toplevel_list_impl));
+
+	ext_foreign_toplevel_list_v1_send_finished(resource);
+	wl_resource_destroy(resource);
+}
+
+static const struct ext_foreign_toplevel_list_v1_interface
+		foreign_toplevel_list_impl = {
+	.stop = foreign_toplevel_list_handle_stop
+};
+
+static void foreign_toplevel_list_resource_destroy(
+		struct wl_resource *resource) {
+	wl_list_remove(wl_resource_get_link(resource));
+}
+
+static void foreign_toplevel_list_bind(struct wl_client *client, void *data,
+		uint32_t version, uint32_t id) {
+	struct wlr_ext_foreign_toplevel_list_v1 *list = data;
+	struct wl_resource *resource = wl_resource_create(client,
+			&ext_foreign_toplevel_list_v1_interface, version, id);
+	if (!resource) {
+		wl_client_post_no_memory(client);
+		return;
+	}
+	wl_resource_set_implementation(resource, &foreign_toplevel_list_impl,
+			list, foreign_toplevel_list_resource_destroy);
+
+	wl_list_insert(&list->resources, wl_resource_get_link(resource));
+
+	struct wlr_ext_foreign_toplevel_handle_v1 *toplevel;
+	wl_list_for_each(toplevel, &list->toplevels, link) {
+		struct wl_resource *toplevel_resource =
+			create_toplevel_resource_for_resource(toplevel, resource);
+		toplevel_send_details_to_toplevel_resource(toplevel,
+			toplevel_resource);
+	}
+}
+
+static void handle_display_destroy(struct wl_listener *listener, void *data) {
+	struct wlr_ext_foreign_toplevel_list_v1 *list =
+		wl_container_of(listener, list, display_destroy);
+	wl_signal_emit_mutable(&list->events.destroy, NULL);
+	wl_list_remove(&list->display_destroy.link);
+	wl_global_destroy(list->global);
+	free(list);
+}
+
+struct wlr_ext_foreign_toplevel_list_v1 *wlr_ext_foreign_toplevel_list_v1_create(
+		struct wl_display *display, uint32_t version) {
+	assert(version <= FOREIGN_TOPLEVEL_LIST_V1_VERSION);
+
+	struct wlr_ext_foreign_toplevel_list_v1 *list = calloc(1, sizeof(*list));
+	if (!list) {
+		return NULL;
+	}
+
+	list->global = wl_global_create(display,
+			&ext_foreign_toplevel_list_v1_interface,
+			version, list,
+			foreign_toplevel_list_bind);
+	if (!list->global) {
+		free(list);
+		return NULL;
+	}
+
+	wl_signal_init(&list->events.destroy);
+	wl_list_init(&list->resources);
+	wl_list_init(&list->toplevels);
+
+	list->display_destroy.notify = handle_display_destroy;
+	wl_display_add_destroy_listener(display, &list->display_destroy);
+
+	return list;
+}