wlr_xdg_session_management_v1: new protocol implementation

See https://gitlab.freedesktop.org/wayland/wayland-protocols/-/merge_requests/18

include/wlr/types/wlr_xdg_session_management_v1.h

@@ -0,0 +1,145 @@
+/*
+ * 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_XDG_SESSION_MANAGEMENT_V1_H
+#define WLR_TYPES_WLR_XDG_SESSION_MANAGEMENT_V1_H
+
+#include <wayland-server-core.h>
+#include <wayland-protocols/xdg-session-management-v1-enum.h>
+
+/**
+ * A toplevel part of a session.
+ */
+struct wlr_xdg_toplevel_session_v1 {
+	struct wl_resource *resource;
+	struct wlr_xdg_session_v1 *session;
+	struct wlr_xdg_toplevel *toplevel;
+	struct wl_list link; // wlr_xdg_session_v1.toplevels
+
+	// Client-provided identifier, unique per session.
+	char *name;
+
+	struct {
+		struct wl_signal destroy;
+
+		// Toplevel session name has changed.
+		struct wl_signal rename;
+	} events;
+
+	struct {
+		bool restorable;
+		struct wl_listener toplevel_destroy;
+	} WLR_PRIVATE;
+};
+
+struct wlr_xdg_session_v1_remove_toplevel_event {
+	const char *name;
+};
+
+/**
+ * An application session.
+ *
+ * When a new session is created, compositors should load any saved state based
+ * on wlr_xdg_session_v1.id (if non-NULL), then call
+ * wlr_xdg_session_v1_notify_created() or wlr_xdg_session_v1_notify_restored().
+ *
+ * Compositors should save toplevel state for all toplevels added to the
+ * session.
+ */
+struct wlr_xdg_session_v1 {
+	struct wl_resource *resource;
+	struct wl_list link; // wlr_xdg_session_manager_v1.sessions
+
+	enum xdg_session_manager_v1_reason reason;
+	char *id;
+	struct wl_list toplevels; // wlr_xdg_toplevel_session_v1.link
+
+	struct {
+		struct wl_signal destroy;
+
+		// All session saved state should be erased.
+		struct wl_signal remove;
+
+		// Toplevel state should be tracked as part of the session.
+		struct wl_signal add_toplevel; // struct wlr_xdg_toplevel_session_v1 *
+
+		// If the toplevel state was saved, it should be restored and
+		// wlr_xdg_toplevel_session_v1_notify_restored() should be called. Then
+		// toplevel state should be tracked as part of the session.
+		struct wl_signal restore_toplevel; // struct wlr_xdg_toplevel_session_v1 *
+
+		// Toplevel state should no longer be tracked as part of the session.
+		struct wl_signal remove_toplevel; // struct wlr_xdg_session_v1_remove_toplevel_event *
+	} events;
+
+	struct {
+		bool initialized; // added or restored
+	} WLR_PRIVATE;
+};
+
+/**
+ * Session manager global.
+ */
+struct wlr_xdg_session_manager_v1 {
+	struct wl_global *global;
+
+	struct wl_list sessions; // wlr_xdg_session_v1.link
+
+	struct {
+		struct wl_signal destroy;
+		struct wl_signal new_session; // struct wlr_xdg_session_v1 *
+	} events;
+
+	struct {
+		struct wl_listener display_destroy;
+	} WLR_PRIVATE;
+};
+
+/**
+ * Create the session manager global.
+ */
+struct wlr_xdg_session_manager_v1 *wlr_xdg_session_manager_v1_create(
+	struct wl_display *display, uint32_t version);
+
+/**
+ * Notify that a new session state has been created.
+ *
+ * This function should be called in response to
+ * wlr_xdg_session_manager_v1.events.new_session if no state could be restored.
+ */
+void wlr_xdg_session_v1_notify_created(struct wlr_xdg_session_v1 *session, const char *session_id);
+
+/**
+ * Notify that the session has been restored.
+ *
+ * This function should be called in response to
+ * wlr_xdg_session_manager_v1.events.new_session if at least some state could
+ * be restored.
+ */
+void wlr_xdg_session_v1_notify_restored(struct wlr_xdg_session_v1 *session);
+
+/**
+ * Notify that the session has been taken over by another client.
+ *
+ * This function destroys the session.
+ */
+void wlr_xdg_session_v1_notify_replaced_and_destroy(struct wlr_xdg_session_v1 *session);
+
+/**
+ * Notify that the toplevel state has been restored.
+ *
+ * This event is part of a toplevel configure sequence.
+ *
+ * This function should be called in response to
+ * wlr_xdg_session_v1.events.restore_toplevel if the toplevel was successfully
+ * restored.
+ */
+uint32_t wlr_xdg_toplevel_session_v1_notify_restored(
+	struct wlr_xdg_toplevel_session_v1 *toplevel_session);
+
+#endif