1 files changed, 592 insertions, 0 deletions
diff --git a/spa/plugins/support/dbus.c b/spa/plugins/support/dbus.c
new file mode 100644
index 0000000..a6b5e58
--- /dev/null
+++ b/spa/plugins/support/dbus.c
@@ -0,0 +1,592 @@
+/* PipeWire
+ *
+ * Copyright © 2018 Wim Taymans
+ *
+ * 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 <string.h>
+#include <stdio.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+#include <dbus/dbus.h>
+
+#include <spa/utils/result.h>
+#include <spa/utils/type.h>
+#include <spa/utils/names.h>
+#include <spa/utils/string.h>
+#include <spa/support/log.h>
+#include <spa/support/plugin.h>
+#include <spa/support/dbus.h>
+
+static struct spa_log_topic log_topic = SPA_LOG_TOPIC(0, "spa.dbus");
+#undef SPA_LOG_TOPIC_DEFAULT
+#define SPA_LOG_TOPIC_DEFAULT &log_topic
+
+struct impl {
+	struct spa_handle handle;
+	struct spa_dbus dbus;
+
+	struct spa_log *log;
+	struct spa_loop_utils *utils;
+
+	struct spa_list connection_list;
+};
+
+struct source_data {
+	struct spa_list link;
+	struct spa_source *source;
+	struct connection *conn;
+};
+
+#define connection_emit(c,m,v,...) spa_hook_list_call(&c->listener_list, struct spa_dbus_connection_events, m, v, ##__VA_ARGS__)
+#define connection_emit_destroy(c)	connection_emit(c, destroy, 0)
+#define connection_emit_disconnected(c)	connection_emit(c, disconnected, 0)
+
+struct connection {
+	struct spa_list link;
+
+	struct spa_dbus_connection this;
+	struct impl *impl;
+	enum spa_dbus_type type;
+	DBusConnection *conn;
+	struct spa_source *dispatch_event;
+	struct spa_list source_list;
+
+	struct spa_hook_list listener_list;
+};
+
+static void source_data_free(void *data)
+{
+	struct source_data *d = data;
+	struct connection *conn = d->conn;
+	struct impl *impl = conn->impl;
+
+	spa_list_remove(&d->link);
+	spa_loop_utils_destroy_source(impl->utils, d->source);
+	free(d);
+}
+
+static void dispatch_cb(void *userdata)
+{
+	struct connection *conn = userdata;
+	struct impl *impl = conn->impl;
+
+	if (dbus_connection_dispatch(conn->conn) == DBUS_DISPATCH_COMPLETE)
+		spa_loop_utils_enable_idle(impl->utils, conn->dispatch_event, false);
+}
+
+static void dispatch_status(DBusConnection *conn, DBusDispatchStatus status, void *userdata)
+{
+	struct connection *c = userdata;
+	struct impl *impl = c->impl;
+
+	spa_loop_utils_enable_idle(impl->utils, c->dispatch_event,
+			status == DBUS_DISPATCH_COMPLETE ? false : true);
+}
+
+static inline uint32_t dbus_to_io(DBusWatch *watch)
+{
+	uint32_t mask;
+	unsigned int flags;
+
+	/* no watch flags for disabled watches */
+	if (!dbus_watch_get_enabled(watch))
+		return 0;
+
+	flags = dbus_watch_get_flags(watch);
+	mask = SPA_IO_HUP | SPA_IO_ERR;
+
+	if (flags & DBUS_WATCH_READABLE)
+		mask |= SPA_IO_IN;
+	if (flags & DBUS_WATCH_WRITABLE)
+		mask |= SPA_IO_OUT;
+
+	return mask;
+}
+
+static inline unsigned int io_to_dbus(uint32_t mask)
+{
+	unsigned int flags = 0;
+
+	if (mask & SPA_IO_IN)
+		flags |= DBUS_WATCH_READABLE;
+	if (mask & SPA_IO_OUT)
+		flags |= DBUS_WATCH_WRITABLE;
+	if (mask & SPA_IO_HUP)
+		flags |= DBUS_WATCH_HANGUP;
+	if (mask & SPA_IO_ERR)
+		flags |= DBUS_WATCH_ERROR;
+	return flags;
+}
+
+static void
+handle_io_event(void *userdata, int fd, uint32_t mask)
+{
+	DBusWatch *watch = userdata;
+
+	if (!dbus_watch_get_enabled(watch)) {
+		fprintf(stderr, "Asked to handle disabled watch: %p %i", (void *) watch, fd);
+		return;
+	}
+	dbus_watch_handle(watch, io_to_dbus(mask));
+}
+
+static dbus_bool_t add_watch(DBusWatch *watch, void *userdata)
+{
+	struct connection *conn = userdata;
+	struct impl *impl = conn->impl;
+	struct source_data *data;
+
+	spa_log_debug(impl->log, "add watch %p %d", watch, dbus_watch_get_unix_fd(watch));
+
+	data = calloc(1, sizeof(struct source_data));
+	data->conn = conn;
+	/* we dup because dbus tends to add the same fd multiple times and our epoll
+	 * implementation does not like that */
+	data->source = spa_loop_utils_add_io(impl->utils,
+				dup(dbus_watch_get_unix_fd(watch)),
+				dbus_to_io(watch), true, handle_io_event, watch);
+	spa_list_append(&conn->source_list, &data->link);
+
+	dbus_watch_set_data(watch, data, source_data_free);
+	return TRUE;
+}
+
+static void remove_watch(DBusWatch *watch, void *userdata)
+{
+	struct connection *conn = userdata;
+	struct impl *impl = conn->impl;
+	spa_log_debug(impl->log, "remove watch %p", watch);
+	dbus_watch_set_data(watch, NULL, NULL);
+}
+
+static void toggle_watch(DBusWatch *watch, void *userdata)
+{
+	struct connection *conn = userdata;
+	struct impl *impl = conn->impl;
+	struct source_data *data;
+
+	spa_log_debug(impl->log, "toggle watch %p", watch);
+
+	if ((data = dbus_watch_get_data(watch)) == NULL)
+		return;
+
+	spa_loop_utils_update_io(impl->utils, data->source, dbus_to_io(watch));
+}
+
+static void
+handle_timer_event(void *userdata, uint64_t expirations)
+{
+	DBusTimeout *timeout = userdata;
+	uint64_t t;
+	struct timespec ts;
+	struct source_data *data;
+	struct connection *conn;
+	struct impl *impl;
+
+	if ((data = dbus_timeout_get_data(timeout)) == NULL)
+		return;
+
+	conn = data->conn;
+	impl = conn->impl;
+
+	spa_log_debug(impl->log, "timeout %p conn:%p impl:%p", timeout, conn, impl);
+
+	if (dbus_timeout_get_enabled(timeout)) {
+		t = dbus_timeout_get_interval(timeout) * SPA_NSEC_PER_MSEC;
+		ts.tv_sec = t / SPA_NSEC_PER_SEC;
+		ts.tv_nsec = t % SPA_NSEC_PER_SEC;
+		spa_loop_utils_update_timer(impl->utils,
+				     data->source, &ts, NULL, false);
+		dbus_timeout_handle(timeout);
+	}
+}
+
+static dbus_bool_t add_timeout(DBusTimeout *timeout, void *userdata)
+{
+	struct connection *conn = userdata;
+	struct impl *impl = conn->impl;
+	struct timespec ts;
+	struct source_data *data;
+	uint64_t t;
+
+	if (!dbus_timeout_get_enabled(timeout))
+		return FALSE;
+
+	spa_log_debug(impl->log, "add timeout %p conn:%p impl:%p", timeout, conn, impl);
+
+	data = calloc(1, sizeof(struct source_data));
+	data->conn = conn;
+	data->source = spa_loop_utils_add_timer(impl->utils, handle_timer_event, timeout);
+	spa_list_append(&conn->source_list, &data->link);
+
+	dbus_timeout_set_data(timeout, data, source_data_free);
+
+	t = dbus_timeout_get_interval(timeout) * SPA_NSEC_PER_MSEC;
+	ts.tv_sec = t / SPA_NSEC_PER_SEC;
+	ts.tv_nsec = t % SPA_NSEC_PER_SEC;
+	spa_loop_utils_update_timer(impl->utils, data->source, &ts, NULL, false);
+
+	return TRUE;
+}
+
+static void remove_timeout(DBusTimeout *timeout, void *userdata)
+{
+	struct connection *conn = userdata;
+	struct impl *impl = conn->impl;
+	spa_log_debug(impl->log, "remove timeout %p conn:%p impl:%p", timeout, conn, impl);
+	dbus_timeout_set_data(timeout, NULL, NULL);
+}
+
+static void toggle_timeout(DBusTimeout *timeout, void *userdata)
+{
+	struct connection *conn = userdata;
+	struct impl *impl = conn->impl;
+	struct source_data *data;
+	struct timespec ts, *tsp;
+
+	if ((data = dbus_timeout_get_data(timeout)) == NULL)
+		return;
+
+	spa_log_debug(impl->log, "toggle timeout %p conn:%p impl:%p", timeout, conn, impl);
+
+	if (dbus_timeout_get_enabled(timeout)) {
+		uint64_t t = dbus_timeout_get_interval(timeout) * SPA_NSEC_PER_MSEC;
+		ts.tv_sec = t / SPA_NSEC_PER_SEC;
+		ts.tv_nsec = t % SPA_NSEC_PER_SEC;
+		tsp = &ts;
+	} else {
+		tsp = NULL;
+	}
+	spa_loop_utils_update_timer(impl->utils, data->source, tsp, NULL, false);
+}
+
+static void wakeup_main(void *userdata)
+{
+	struct connection *this = userdata;
+	struct impl *impl = this->impl;
+
+	spa_loop_utils_enable_idle(impl->utils, this->dispatch_event, true);
+}
+
+static void connection_close(struct connection *this);
+
+static DBusHandlerResult filter_message (DBusConnection *connection,
+		DBusMessage *message, void *user_data)
+{
+	struct connection *this = user_data;
+	struct impl *impl = this->impl;
+
+	if (dbus_message_is_signal(message, DBUS_INTERFACE_LOCAL, "Disconnected")) {
+		spa_log_debug(impl->log, "dbus connection %p disconnected", this);
+		connection_close(this);
+		connection_emit_disconnected(this);
+	}
+	return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+}
+
+static const char *type_to_string(enum spa_dbus_type type) {
+	switch (type) {
+		case SPA_DBUS_TYPE_SESSION: return "session";
+		case SPA_DBUS_TYPE_SYSTEM: return "system";
+		case SPA_DBUS_TYPE_STARTER: return "starter";
+		default: return "unknown";
+	}
+}
+
+static void *
+impl_connection_get(struct spa_dbus_connection *conn)
+{
+	struct connection *this = SPA_CONTAINER_OF(conn, struct connection, this);
+	struct impl *impl = this->impl;
+	DBusError error;
+
+	if (this->conn != NULL)
+		return this->conn;
+
+	dbus_error_init(&error);
+
+	this->conn = dbus_bus_get_private((DBusBusType)this->type, &error);
+	if (this->conn == NULL)
+		goto error;
+
+	dbus_connection_set_exit_on_disconnect(this->conn, false);
+	if (!dbus_connection_add_filter(this->conn, filter_message, this, NULL))
+		goto error_filter;
+
+	dbus_connection_set_dispatch_status_function(this->conn, dispatch_status, this, NULL);
+	dbus_connection_set_watch_functions(this->conn, add_watch, remove_watch, toggle_watch, this,
+					    NULL);
+	dbus_connection_set_timeout_functions(this->conn, add_timeout, remove_timeout,
+					      toggle_timeout, this, NULL);
+	dbus_connection_set_wakeup_main_function(this->conn, wakeup_main, this, NULL);
+
+	return this->conn;
+
+error:
+	spa_log_error(impl->log, "Failed to connect to %s bus: %s", type_to_string(this->type), error.message);
+	dbus_error_free(&error);
+	errno = ECONNREFUSED;
+	return NULL;
+error_filter:
+	spa_log_error(impl->log, "Failed to create filter");
+	dbus_connection_close(this->conn);
+	dbus_connection_unref(this->conn);
+	this->conn = NULL;
+	errno = ENOMEM;
+	return NULL;
+}
+
+
+static void connection_close(struct connection *this)
+{
+	if (this->conn) {
+		dbus_connection_remove_filter(this->conn, filter_message, this);
+		dbus_connection_close(this->conn);
+
+		/* Someone may still hold a ref to the handle from get(), so the
+		 * unref below may not be the final one. For that case, reset
+		 * all callbacks we defined to be sure they are not called. */
+		dbus_connection_set_dispatch_status_function(this->conn, NULL, NULL, NULL);
+		dbus_connection_set_watch_functions(this->conn, NULL, NULL, NULL, NULL, NULL);
+		dbus_connection_set_timeout_functions(this->conn, NULL, NULL, NULL, NULL, NULL);
+		dbus_connection_set_wakeup_main_function(this->conn, NULL, NULL, NULL);
+
+		dbus_connection_unref(this->conn);
+	}
+	this->conn = NULL;
+}
+
+static void connection_free(struct connection *conn)
+{
+	struct impl *impl = conn->impl;
+	struct source_data *data;
+
+	spa_list_remove(&conn->link);
+
+	connection_close(conn);
+
+	spa_list_consume(data, &conn->source_list, link)
+		source_data_free(data);
+
+	spa_loop_utils_destroy_source(impl->utils, conn->dispatch_event);
+
+	spa_hook_list_clean(&conn->listener_list);
+
+	free(conn);
+}
+
+static void
+impl_connection_destroy(struct spa_dbus_connection *conn)
+{
+	struct connection *this = SPA_CONTAINER_OF(conn, struct connection, this);
+	struct impl *impl = this->impl;
+
+	connection_emit_destroy(this);
+
+	spa_log_debug(impl->log, "destroy conn %p", this);
+	connection_free(this);
+}
+
+static void
+impl_connection_add_listener(struct spa_dbus_connection *conn,
+			struct spa_hook *listener,
+			const struct spa_dbus_connection_events *events,
+			void *data)
+{
+	struct connection *this = SPA_CONTAINER_OF(conn, struct connection, this);
+	spa_hook_list_append(&this->listener_list, listener, events, data);
+}
+
+static const struct spa_dbus_connection impl_connection = {
+	SPA_VERSION_DBUS_CONNECTION,
+	impl_connection_get,
+	impl_connection_destroy,
+	impl_connection_add_listener,
+};
+
+static struct spa_dbus_connection *
+impl_get_connection(void *object,
+		    enum spa_dbus_type type)
+{
+        struct impl *impl = object;
+	struct connection *conn;
+	int res;
+
+	conn = calloc(1, sizeof(struct connection));
+	conn->this = impl_connection;
+	conn->impl = impl;
+	conn->type = type;
+	conn->dispatch_event = spa_loop_utils_add_idle(impl->utils,
+						false, dispatch_cb, conn);
+	if (conn->dispatch_event == NULL)
+		goto no_event;
+
+	spa_list_init(&conn->source_list);
+	spa_hook_list_init(&conn->listener_list);
+
+	spa_list_append(&impl->connection_list, &conn->link);
+
+	spa_log_debug(impl->log, "new conn %p", conn);
+
+	return &conn->this;
+
+no_event:
+	res = -errno;
+	spa_log_error(impl->log, "Failed to create idle event: %m");
+	free(conn);
+	errno = -res;
+	return NULL;
+}
+
+static const struct spa_dbus_methods impl_dbus = {
+	SPA_VERSION_DBUS_METHODS,
+	.get_connection = impl_get_connection,
+};
+
+static int impl_get_interface(struct spa_handle *handle, const char *type, void **interface)
+{
+	struct impl *this;
+
+	spa_return_val_if_fail(handle != NULL, -EINVAL);
+	spa_return_val_if_fail(interface != NULL, -EINVAL);
+
+	this = (struct impl *) handle;
+
+	if (spa_streq(type, SPA_TYPE_INTERFACE_DBus))
+		*interface = &this->dbus;
+	else
+		return -ENOENT;
+
+	return 0;
+}
+
+static int impl_clear(struct spa_handle *handle)
+{
+	struct impl *impl = (struct impl *) handle;
+	struct connection *conn;
+
+	spa_return_val_if_fail(handle != NULL, -EINVAL);
+
+	spa_list_consume(conn, &impl->connection_list, link)
+		connection_free(conn);
+	return 0;
+}
+
+static size_t
+impl_get_size(const struct spa_handle_factory *factory,
+	      const struct spa_dict *params)
+{
+	return sizeof(struct impl);
+}
+
+static int
+impl_init(const struct spa_handle_factory *factory,
+	  struct spa_handle *handle,
+	  const struct spa_dict *info,
+	  const struct spa_support *support,
+	  uint32_t n_support)
+{
+	struct impl *this;
+
+	spa_return_val_if_fail(factory != NULL, -EINVAL);
+	spa_return_val_if_fail(handle != NULL, -EINVAL);
+
+	handle->get_interface = impl_get_interface;
+	handle->clear = impl_clear;
+
+	this = (struct impl *) handle;
+	spa_list_init(&this->connection_list);
+
+	this->dbus.iface = SPA_INTERFACE_INIT(
+			SPA_TYPE_INTERFACE_DBus,
+			SPA_VERSION_DBUS,
+			&impl_dbus, this);
+
+	this->log = spa_support_find(support, n_support, SPA_TYPE_INTERFACE_Log);
+	spa_log_topic_init(this->log, &log_topic);
+
+	this->utils = spa_support_find(support, n_support, SPA_TYPE_INTERFACE_LoopUtils);
+
+	if (this->utils == NULL) {
+		spa_log_error(this->log, "a LoopUtils is needed");
+		return -EINVAL;
+	}
+
+	spa_log_debug(this->log, "%p: initialized", this);
+
+	return 0;
+}
+
+static const struct spa_interface_info impl_interfaces[] = {
+	{SPA_TYPE_INTERFACE_DBus,},
+};
+
+static int
+impl_enum_interface_info(const struct spa_handle_factory *factory,
+			 const struct spa_interface_info **info,
+			 uint32_t *index)
+{
+	spa_return_val_if_fail(factory != NULL, -EINVAL);
+	spa_return_val_if_fail(info != NULL, -EINVAL);
+	spa_return_val_if_fail(index != NULL, -EINVAL);
+
+	switch (*index) {
+	case 0:
+		*info = &impl_interfaces[*index];
+		break;
+	default:
+		return 0;
+	}
+	(*index)++;
+
+	return 1;
+}
+
+static const struct spa_handle_factory dbus_factory = {
+	SPA_VERSION_HANDLE_FACTORY,
+	SPA_NAME_SUPPORT_DBUS,
+	NULL,
+	impl_get_size,
+	impl_init,
+	impl_enum_interface_info,
+};
+
+SPA_EXPORT
+int spa_handle_factory_enum(const struct spa_handle_factory **factory, uint32_t *index)
+{
+	spa_return_val_if_fail(factory != NULL, -EINVAL);
+	spa_return_val_if_fail(index != NULL, -EINVAL);
+
+	switch (*index) {
+	case 0:
+		*factory = &dbus_factory;
+		break;
+	default:
+		return 0;
+	}
+	(*index)++;
+	return 1;
+}