extensions: implement new session manager extension

This extension, implemented in module-session-manager, implements
a set of objects that are useful for session managers.

src/modules/module-session-manager/client-session.c

@@ -0,0 +1,270 @@
+/* PipeWire
+ *
+ * Copyright © 2019 Collabora Ltd.
+ *   @author George Kiagiadakis <george.kiagiadakis@collabora.com>
+ *
+ * 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.
+ */
+
+#include <stdbool.h>
+#include <string.h>
+
+#include <pipewire/pipewire.h>
+#include <extensions/session-manager.h>
+
+#include "client-session.h"
+#include "session.h"
+#include "endpoint-link.h"
+
+#include <pipewire/private.h>
+
+#define NAME "client-session"
+
+struct factory_data {
+	struct pw_factory *factory;
+	struct pw_module *module;
+	struct spa_hook module_listener;
+};
+
+static struct endpoint_link *find_link(struct client_session *this, uint32_t id)
+{
+	struct endpoint_link *l;
+	spa_list_for_each(l, &this->links, link) {
+		if (l->id == id)
+			return l;
+	}
+	return NULL;
+}
+
+static int client_session_update(void *object,
+				uint32_t change_mask,
+				uint32_t n_params,
+				const struct spa_pod **params,
+				const struct pw_session_info *info)
+{
+	struct client_session *this = object;
+	struct session *session = &this->session;
+
+	return session_update(session, change_mask, n_params, params, info);
+}
+
+static int client_session_link_update(void *object,
+				uint32_t link_id,
+				uint32_t change_mask,
+				uint32_t n_params,
+				const struct spa_pod **params,
+				const struct pw_endpoint_link_info *info)
+{
+	struct client_session *this = object;
+	struct session *session = &this->session;
+	struct endpoint_link *link = find_link(this, link_id);
+	struct pw_properties *props = NULL;
+
+	if (!link) {
+		struct pw_core *core = pw_global_get_core(session->global);
+		const char *keys[] = {
+			PW_KEY_FACTORY_ID,
+			PW_KEY_CLIENT_ID,
+			PW_KEY_SESSION_ID,
+			NULL
+		};
+
+		link = calloc(1, sizeof(struct endpoint_link));
+		if (!link)
+			goto no_mem;
+
+		props = pw_properties_new(NULL, NULL);
+		if (!props)
+			goto no_mem;
+		pw_properties_copy_keys (session->props, props, keys);
+
+		if (endpoint_link_init(link, link_id, session->info.id,
+					this, core, props) < 0)
+			goto no_mem;
+
+		spa_list_append(&this->links, &link->link);
+	}
+	else if (change_mask & PW_CLIENT_SESSION_LINK_UPDATE_DESTROYED) {
+		endpoint_link_clear(link);
+		spa_list_remove(&link->link);
+		free(link);
+		link = NULL;
+	}
+
+	return link ?
+		endpoint_link_update(link, change_mask, n_params, params, info)
+		: 0;
+
+       no_mem:
+	if (props)
+		pw_properties_free(props);
+	free(link);
+	pw_log_error(NAME" %p: cannot update link: no memory", this);
+	pw_resource_error(this->resource, -ENOMEM,
+		NAME" %p: cannot update link: no memory", this);
+	return -ENOMEM;
+}
+
+static struct pw_client_session_proxy_methods methods = {
+	PW_VERSION_CLIENT_SESSION_PROXY_METHODS,
+	.update = client_session_update,
+	.link_update = client_session_link_update,
+};
+
+static void client_session_destroy(void *data)
+{
+	struct client_session *this = data;
+	struct endpoint_link *l;
+
+	pw_log_debug(NAME" %p: destroy", this);
+
+	spa_list_consume(l, &this->links, link) {
+		endpoint_link_clear(l);
+		spa_list_remove(&l->link);
+		free(l);
+	}
+	session_clear(&this->session);
+	spa_hook_remove(&this->resource_listener);
+
+	free(this);
+}
+
+static const struct pw_resource_events resource_events = {
+	PW_VERSION_RESOURCE_EVENTS,
+	.destroy = client_session_destroy,
+};
+
+static void *create_object(void *data,
+			   struct pw_resource *owner_resource,
+			   uint32_t type,
+			   uint32_t version,
+			   struct pw_properties *properties,
+			   uint32_t new_id)
+{
+	struct factory_data *d = data;
+	struct pw_factory *factory = d->factory;
+	struct client_session *this;
+	struct pw_client *owner = pw_resource_get_client(owner_resource);
+	struct pw_core *core = pw_client_get_core(owner);
+
+	this = calloc(1, sizeof(struct client_session));
+	if (this == NULL)
+		goto no_mem;
+
+	spa_list_init(&this->links);
+
+	pw_log_debug(NAME" %p: new", this);
+
+	if (!properties)
+		properties = pw_properties_new(NULL, NULL);
+	if (!properties)
+		goto no_mem;
+
+	pw_properties_setf(properties, PW_KEY_CLIENT_ID, "%d", owner->global->id);
+	pw_properties_setf(properties, PW_KEY_FACTORY_ID, "%d", factory->global->id);
+
+	this->resource = pw_resource_new(owner, new_id, PW_PERM_RWX, type, version, 0);
+	if (this->resource == NULL)
+		goto no_mem;
+
+	if (session_init(&this->session, this, core, properties) < 0)
+		goto no_mem;
+
+	pw_resource_add_listener(this->resource, &this->resource_listener,
+				 &resource_events, this);
+	pw_resource_add_object_listener(this->resource, &this->object_listener,
+					&methods, this);
+
+	return this;
+
+      no_mem:
+	if (properties)
+		pw_properties_free(properties);
+	if (this && this->resource)
+		pw_resource_destroy(this->resource);
+	free(this);
+	pw_log_error("can't create client session: no memory");
+	pw_resource_error(owner_resource, -ENOMEM,
+			"can't create client session: no memory");
+	return NULL;
+}
+
+static const struct pw_factory_implementation impl_factory = {
+	PW_VERSION_FACTORY_IMPLEMENTATION,
+	.create_object = create_object,
+};
+
+static void module_destroy(void *data)
+{
+	struct factory_data *d = data;
+
+	spa_hook_remove(&d->module_listener);
+	pw_factory_destroy(d->factory);
+}
+
+static void module_registered(void *data)
+{
+	struct factory_data *d = data;
+	struct pw_module *module = d->module;
+	struct pw_factory *factory = d->factory;
+	struct spa_dict_item items[1];
+	char id[16];
+	int res;
+
+	snprintf(id, sizeof(id), "%d", module->global->id);
+	items[0] = SPA_DICT_ITEM_INIT(PW_KEY_MODULE_ID, id);
+	pw_factory_update_properties(factory, &SPA_DICT_INIT(items, 1));
+
+	if ((res = pw_factory_register(factory, NULL)) < 0) {
+		pw_log_error(NAME" %p: can't register factory: %s", factory, spa_strerror(res));
+	}
+}
+
+static const struct pw_module_events module_events = {
+	PW_VERSION_MODULE_EVENTS,
+	.destroy = module_destroy,
+	.registered = module_registered,
+};
+
+int client_session_factory_init(struct pw_module *module)
+{
+	struct pw_core *core = pw_module_get_core(module);
+	struct pw_factory *factory;
+	struct factory_data *data;
+
+	factory = pw_factory_new(core,
+				 "client-session",
+				 PW_TYPE_INTERFACE_Session,
+				 PW_VERSION_CLIENT_SESSION_PROXY,
+				 NULL,
+				 sizeof(*data));
+	if (factory == NULL)
+		return -ENOMEM;
+
+	data = pw_factory_get_user_data(factory);
+	data->factory = factory;
+	data->module = module;
+
+	pw_factory_set_implementation(factory, &impl_factory, data);
+
+	pw_module_add_listener(module, &data->module_listener, &module_events, data);
+
+	return 0;
+}