Create & implement transient seat protocol

include/wlr/types/wlr_transient_seat_v1.h

@@ -0,0 +1,38 @@
+/*
+ * 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_TRANSIENT_SEAT_V1_H
+#define WLR_TYPES_WLR_TRANSIENT_SEAT_V1_H
+
+#include <wayland-server-core.h>
+#include <wayland-server-protocol.h>
+
+struct wlr_seat;
+
+struct wlr_transient_seat_manager_v1 {
+	struct wl_global *global;
+	struct wl_listener display_destroy;
+
+	struct wlr_seat *(*find_seat)(const char *name);
+	struct wlr_seat *(*create_seat)(const char *name);
+	void (*destroy_seat)(struct wlr_seat *seat);
+
+	struct wl_list transient_seats;
+};
+
+struct wlr_transient_seat_v1 {
+	struct wlr_seat *seat;
+	struct wl_resource *resource;
+	struct wlr_transient_seat_manager_v1 *manager;
+	struct wl_list link;
+};
+
+struct wlr_transient_seat_manager_v1 *wlr_transient_seat_manager_v1_create(
+		struct wl_display *display);
+
+#endif /* WLR_TYPES_WLR_TRANSIENT_SEAT_V1_H */

protocol/meson.build

@@ -44,6 +44,7 @@ protocols = {
 	'wlr-output-power-management-unstable-v1': 'wlr-output-power-management-unstable-v1.xml',
 	'wlr-screencopy-unstable-v1': 'wlr-screencopy-unstable-v1.xml',
 	'wlr-virtual-pointer-unstable-v1': 'wlr-virtual-pointer-unstable-v1.xml',
+	'transient-seat-unstable-v1': 'transient-seat-unstable-v1.xml',
 }
 
 protocols_code = {}

protocol/transient-seat-unstable-v1.xml

@@ -0,0 +1,89 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<protocol name="transient_seat_unstable_v1">
+  <copyright>
+    Copyright © 2020 Andri Yngvason
+
+    Permission is hereby granted, free of charge, to any person obtaining a
+    copy of this software and associated documentation files (the "Software"),
+    to deal in the Software without restriction, including without limitation
+    the rights to use, copy, modify, merge, publish, distribute, sublicense,
+    and/or sell copies of the Software, and to permit persons to whom the
+    Software is furnished to do so, subject to the following conditions:
+
+    The above copyright notice and this permission notice (including the next
+    paragraph) shall be included in all copies or substantial portions of the
+    Software.
+
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+    THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+    FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+    DEALINGS IN THE SOFTWARE.
+  </copyright>
+
+  <description summary="Protocol for creating temporary seats">
+    The transient seat protocol can be used by clients to create independent
+    seats that will be removed when the client disconnects. The client also gets
+    a handle to the seat which can be used to remove the seat.
+  </description>
+
+  <interface name="zext_transient_seat_manager_v1" version="1">
+    <request name="create">
+      <description summary="Create a transient seat">
+        Create a new seat that is removed when the client closes the connection.
+
+        The client may suggest a name for the seat, but the server may choose
+        whichever name it sees fit, except the name must not collide with the
+        name of another seat.
+
+        It is suggested that the client choose a sufficiently unique name, e.g.
+        something containing the pid and an incremental numeric value.
+      </description>
+      <arg name="suggested_name" type="string"/>
+      <arg name="seat" type="new_id" interface="zext_transient_seat_v1"/>
+    </request>
+
+    <request name="destroy" type="destructor">
+      <description summary="Destroy the manager">
+        Destroy the manager
+      </description>
+    </request>
+  </interface>
+
+  <interface name="zext_transient_seat_v1" version="1">
+    <enum name="error">
+      <entry name="unspec" value="0"
+        summary="Operation failed for unspecified reason"/>
+      <entry name="name_taken" value="1"
+        summary="The suggested name was already taken"/>
+      <entry name="invalid_name" value="2"
+        summary="The suggested name contains invalid characters"/>
+    </enum>
+
+    <event name="failed">
+      <description summary="seat creation failed">
+        This event indicates that the seat creation failed. No event is
+        generated after this and the client should destroy the transient seat
+        object.
+      </description>
+      <arg name="error" type="uint" enum="error"/>
+    </event>
+
+    <event name="ready">
+      <description summary="seat has been created">
+        This event indicates that the seat has been created and tells the client
+        which name was chosen for it. It is generated after the seat is created.
+        No event is generated after this.
+      </description>
+      <arg name="name" type="string"/>
+    </event>
+
+    <request name="destroy" type="destructor">
+      <description summary="Destroy the seat">
+        Destroy the seat
+      </description>
+    </request>
+  </interface>
+</protocol>

types/meson.build

@@ -59,6 +59,7 @@ wlr_files += files(
 	'wlr_tablet_tool.c',
 	'wlr_text_input_v3.c',
 	'wlr_touch.c',
+	'wlr_transient_seat_v1.c',
 	'wlr_viewporter.c',
 	'wlr_virtual_keyboard_v1.c',
 	'wlr_virtual_pointer_v1.c',

types/wlr_transient_seat_v1.c

@@ -0,0 +1,167 @@
+#include <assert.h>
+#include <stdlib.h>
+#include <wayland-util.h>
+#include <wlr/types/wlr_seat.h>
+#include <wlr/types/wlr_transient_seat_v1.h>
+#include "transient-seat-unstable-v1-protocol.h"
+
+static const struct zext_transient_seat_manager_v1_interface manager_impl;
+static const struct zext_transient_seat_v1_interface transient_seat_impl;
+
+void transient_seat_handle_destroy(struct wl_client *client,
+		struct wl_resource *resource);
+
+static struct wlr_transient_seat_manager_v1 *manager_from_resource(
+		struct wl_resource *resource) {
+	assert(wl_resource_instance_of(resource,
+		&zext_transient_seat_manager_v1_interface, &manager_impl));
+	return wl_resource_get_user_data(resource);
+}
+
+static struct wlr_transient_seat_v1 *transient_seat_from_resource(
+		struct wl_resource *resource) {
+	assert(wl_resource_instance_of(resource,
+		&zext_transient_seat_v1_interface, &transient_seat_impl));
+	return wl_resource_get_user_data(resource);
+}
+
+static void manager_handle_destroy(struct wl_client *client,
+		struct wl_resource *manager_resource) {
+	wl_resource_destroy(manager_resource);
+}
+
+static void transient_seat_destroy(struct wlr_transient_seat_v1 *transient_seat) {
+	wl_list_remove(&transient_seat->link);
+	if (transient_seat->seat) {
+		transient_seat->manager->destroy_seat(transient_seat->seat);
+	}
+	wl_resource_set_user_data(transient_seat->resource, NULL);
+	free(transient_seat);
+}
+
+static void transient_seat_destroy_resource(struct wl_resource *resource) {
+	struct wlr_transient_seat_v1 *transient_seat =
+		transient_seat_from_resource(resource);
+	if (transient_seat) {
+		transient_seat_destroy(transient_seat);
+	}
+}
+
+void transient_seat_handle_destroy(struct wl_client *client,
+		struct wl_resource *resource) {
+	wl_resource_destroy(resource);
+}
+
+static const struct zext_transient_seat_v1_interface transient_seat_impl = {
+	.destroy = transient_seat_handle_destroy,
+};
+
+static void manager_create_transient_seat(struct wl_client *client,
+		struct wl_resource *manager_resource,
+		const char *suggested_name, uint32_t id) {
+	struct wlr_transient_seat_manager_v1 *manager =
+		manager_from_resource(manager_resource);
+
+	struct wlr_transient_seat_v1 *transient_seat =
+		calloc(1, sizeof(struct wlr_transient_seat_v1));
+	if (!transient_seat) {
+		wl_client_post_no_memory(client);
+		return;
+	}
+
+	transient_seat->manager = manager;
+
+	transient_seat->resource = wl_resource_create(client,
+		&zext_transient_seat_v1_interface,
+		wl_resource_get_version(manager_resource), id);
+	if (!transient_seat->resource) {
+		wl_client_post_no_memory(client);
+		free(transient_seat);
+		return;
+	}
+
+	wl_resource_set_implementation(transient_seat->resource,
+		&transient_seat_impl, transient_seat,
+		transient_seat_destroy_resource);
+
+	wl_list_insert(&manager->transient_seats, &transient_seat->link);
+
+	if (manager->find_seat(suggested_name)) {
+		zext_transient_seat_v1_send_failed(transient_seat->resource,
+				ZEXT_TRANSIENT_SEAT_V1_ERROR_NAME_TAKEN);
+		transient_seat_destroy(transient_seat);
+		return;
+	}
+
+	transient_seat->seat = manager->create_seat(suggested_name);
+	if (transient_seat->seat) {
+		zext_transient_seat_v1_send_ready(transient_seat->resource,
+				suggested_name);
+	} else {
+		zext_transient_seat_v1_send_failed(transient_seat->resource,
+				ZEXT_TRANSIENT_SEAT_V1_ERROR_UNSPEC);
+		transient_seat_destroy(transient_seat);
+	}
+}
+
+static const struct zext_transient_seat_manager_v1_interface manager_impl = {
+	.create = manager_create_transient_seat,
+	.destroy = manager_handle_destroy,
+};
+
+static void handle_display_destroy(struct wl_listener *listener, void *data) {
+	struct wlr_transient_seat_manager_v1 *manager =
+		wl_container_of(listener, manager, display_destroy);
+
+	struct wlr_transient_seat_v1 *transient_seat, *tmp_transient_seat;
+	wl_list_for_each_safe(transient_seat, tmp_transient_seat,
+			&manager->transient_seats, link) {
+		transient_seat_destroy(transient_seat);
+	}
+
+	wl_list_remove(&manager->display_destroy.link);
+	wl_global_destroy(manager->global);
+	free(manager);
+}
+
+static void transient_seat_manager_bind(struct wl_client *client, void *data,
+		uint32_t version, uint32_t id) {
+	struct wlr_virtual_pointer_manager_v1 *manager = data;
+
+	struct wl_resource *resource = wl_resource_create(client,
+		&zext_transient_seat_manager_v1_interface, version, id);
+
+	if (!resource) {
+		wl_client_post_no_memory(client);
+		return;
+	}
+
+	wl_resource_set_implementation(resource, &manager_impl, manager, NULL);
+}
+
+struct wlr_transient_seat_manager_v1 *wlr_transient_seat_manager_v1_create(
+		struct wl_display *display) {
+	struct wlr_transient_seat_manager_v1 *manager =
+		calloc(1, sizeof(struct wlr_transient_seat_manager_v1));
+	if (!manager) {
+		return NULL;
+	}
+
+	wl_list_init(&manager->transient_seats);
+
+	manager->global = wl_global_create(display,
+		&zext_transient_seat_manager_v1_interface, 1, manager,
+		transient_seat_manager_bind);
+	if (!manager->global) {
+		goto failure;
+	}
+
+	manager->display_destroy.notify = handle_display_destroy;
+	wl_display_add_destroy_listener(display, &manager->display_destroy);
+
+	return manager;
+
+failure:
+	free(manager);
+	return NULL;
+}