move SAP in separate module

The idea is to have the rtp-source and rtp-sink be separate modules that can be loaded a static ip/port as well. The SAP module would then expose existing rtp-sinks or additionally load rtp-sources based on SAP messages. This makes things a bit more flexible when we also want to expose the rtp-sink using zeroconf, for example.
2025-11-02 09:01:50 -05:00 · 2023-02-20 18:10:09 +01:00 · 2023-02-20 18:10:09 +01:00 · cb1e5661dc
commit cb1e5661dc
parent 7a31278511
3 changed files with 816 additions and 193 deletions
--- a/src/modules/module-rtp-sap.c
+++ b/src/modules/module-rtp-sap.c
@ -0,0 +1,765 @@
+/* PipeWire */
+/* SPDX-FileCopyrightText: Copyright © 2022 Wim Taymans <wim.taymans@gmail.com> */
+/* SPDX-License-Identifier: MIT */
+
+#include "config.h"
+
+#include <limits.h>
+#include <unistd.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+#include <sys/ioctl.h>
+#include <arpa/inet.h>
+#include <netinet/ip.h>
+#include <netinet/in.h>
+#include <net/if.h>
+#include <ctype.h>
+
+#include <spa/utils/hook.h>
+#include <spa/utils/result.h>
+#include <spa/utils/ringbuffer.h>
+#include <spa/utils/json.h>
+#include <spa/debug/types.h>
+#include <spa/debug/dict.h>
+
+#include <pipewire/pipewire.h>
+#include <pipewire/impl.h>
+
+#include <module-rtp/sap.h>
+#include <module-rtp/rtp.h>
+
+
+/** \page page_module_rtp_sap PipeWire Module: Announce and receive RTP streams
+ *
+ * The `rtp-sap` module announces RTP stream with the sess.sap.announce property
+ * set to true.
+ *
+ * It will also create source rtp streams that are announced with SAP when they
+ * match the pattern.
+ *
+ * ## Module Options
+ *
+ * Options specific to the behavior of this module
+ *
+ * - `sap.ip = <str>`: IP address of the SAP messages, default "224.0.0.56"
+ * - `sap.port = <int>`: port of the SAP messages, default 9875
+ * - `source.ip =<str>`: source IP address, default "0.0.0.0"
+ * - `destination.ip =<str>`: destination IP address, default "224.0.0.56"
+ * - `destination.port =<int>`: destination port, default random beteen 46000 and 47024
+ * - `local.ifname = <str>`: interface name to use
+ * - `net.ttl = <int>`: TTL to use, default 1
+ * - `net.loop = <bool>`: loopback multicast, default false
+ *
+ * ## General options
+ *
+ * Options with well-known behavior:
+ *
+ * - \ref PW_KEY_REMOTE_NAME
+ *
+ * ## Example configuration
+ *\code{.unparsed}
+ * context.modules = [
+ * {   name = libpipewire-module-rtp-sap
+ *     args = {
+ *         #sap.ip = "224.0.0.56"
+ *         #sap.port = 9875
+ *         #source.ip = "0.0.0.0"
+ *         #local.ifname = "eth0"
+ *         #net.ttl = 1
+ *         #net.loop = false
+ *         stream.props = {
+ *            #media.class = "Audio/Source"
+ *            #node.name = "rtp-source"
+ *         }
+ *         stream.rules = [
+ *             {   matches = [
+ *                     # any of the items in matches needs to match, if one does,
+ *                     # actions are emited.
+ *                     {   # all keys must match the value. ~ in value starts regex.
+ *                         #rtp.origin = "wim 3883629975 0 IN IP4 0.0.0.0"
+ *                         #rtp.payload = "127"
+ *                         #rtp.fmt = "L16/48000/2"
+ *                         #rtp.session = "PipeWire RTP Stream on fedora"
+ *                         #rtp.ts-offset = 0
+ *                         #rtp.ts-refclk = "private"
+ *                     }
+ *                 ]
+ *                 actions = {
+ *                     create-stream = {
+ *                         #sess.latency.msec = 100
+ *                         #sess.ts-direct = false
+ *                         #target.object = ""
+ *                     }
+ *                 }
+ *             }
+ *         ]
+ *     }
+ *     }
+ *}
+ *]
+ *\endcode
+ *
+ * \since 0.3.67
+ */
+
+#define NAME "rtp-sap"
+
+PW_LOG_TOPIC_STATIC(mod_topic, "mod." NAME);
+#define PW_LOG_TOPIC_DEFAULT mod_topic
+
+#define SAP_INTERVAL_SEC	5
+#define SAP_MIME_TYPE		"application/sdp"
+
+#define DEFAULT_SAP_IP		"224.0.0.56"
+#define DEFAULT_SAP_PORT	9875
+
+#define DEFAULT_PORT		46000
+#define DEFAULT_SOURCE_IP	"0.0.0.0"
+#define DEFAULT_DESTINATION_IP	"224.0.0.56"
+#define DEFAULT_TTL		1
+#define DEFAULT_LOOP		false
+
+#define USAGE	"sap.ip=<SAP IP address to send announce, default:"DEFAULT_SAP_IP"> "		\
+		"sap.port=<SAP port to send on, default:"SPA_STRINGIFY(DEFAULT_SAP_PORT)"> "	\
+		"source.ip=<source IP address, default:"DEFAULT_SOURCE_IP"> "			\
+		"destination.ip=<destination IP address, default:"DEFAULT_DESTINATION_IP"> "	\
+		"local.ifname=<local interface name to use> "					\
+		"net.ttl=<desired TTL, default:"SPA_STRINGIFY(DEFAULT_TTL)"> "			\
+		"net.loop=<desired loopback, default:"SPA_STRINGIFY(DEFAULT_LOOP)"> "
+
+static const struct spa_dict_item module_info[] = {
+	{ PW_KEY_MODULE_AUTHOR, "Wim Taymans <wim.taymans@gmail.com>" },
+	{ PW_KEY_MODULE_DESCRIPTION, "RTP Sink" },
+	{ PW_KEY_MODULE_USAGE, USAGE },
+	{ PW_KEY_MODULE_VERSION, PACKAGE_VERSION },
+};
+
+struct session {
+	struct spa_list link;
+
+	struct impl *impl;
+	struct node *node;
+
+	uint16_t msg_id_hash;
+	uint32_t ntp;
+
+	uint32_t ts_offset;
+	char *ts_refclk;
+
+	char *media_type;
+	char *mime_type;
+	char *session_name;
+	int payload;
+	uint32_t rate;
+	uint32_t channels;
+	float ptime;
+
+	uint16_t dst_port;
+	struct sockaddr_storage dst_addr;
+	socklen_t dst_len;
+	uint16_t ttl;
+
+	unsigned has_sent_sap:1;
+
+	struct pw_properties *props;
+	struct pw_impl_module *module;
+};
+
+struct node {
+	struct impl *impl;
+
+	uint32_t id;
+
+	struct pw_proxy *proxy;
+	struct spa_hook proxy_listener;
+	struct spa_hook node_listener;
+
+	struct pw_node_info *info;
+	struct session *session;
+};
+
+
+struct impl {
+	struct pw_properties *props;
+
+	struct pw_loop *loop;
+
+	struct pw_impl_module *module;
+	struct spa_hook module_listener;
+
+	struct pw_core *core;
+	struct spa_hook core_listener;
+	struct spa_hook core_proxy_listener;
+
+	struct pw_registry *registry;
+	struct spa_hook registry_listener;
+
+	struct spa_source *timer;
+
+	unsigned int do_disconnect:1;
+
+	char *ifname;
+	bool ttl;
+	bool mcast_loop;
+
+	struct sockaddr_storage src_addr;
+	socklen_t src_len;
+
+	uint16_t sap_port;
+	struct sockaddr_storage sap_addr;
+	socklen_t sap_len;
+
+	int sap_fd;
+
+	struct spa_list sessions;
+};
+
+static int parse_address(const char *address, uint16_t port,
+		struct sockaddr_storage *addr, socklen_t *len)
+{
+	struct sockaddr_in *sa4 = (struct sockaddr_in*)addr;
+	struct sockaddr_in6 *sa6 = (struct sockaddr_in6*)addr;
+
+	if (inet_pton(AF_INET, address, &sa4->sin_addr) > 0) {
+		sa4->sin_family = AF_INET;
+		sa4->sin_port = htons(port);
+		*len = sizeof(*sa4);
+	} else if (inet_pton(AF_INET6, address, &sa6->sin6_addr) > 0) {
+		sa6->sin6_family = AF_INET6;
+		sa6->sin6_port = htons(port);
+		*len = sizeof(*sa6);
+	} else
+		return -EINVAL;
+
+	return 0;
+}
+
+static bool is_multicast(struct sockaddr *sa, socklen_t salen)
+{
+	if (sa->sa_family == AF_INET) {
+		static const uint32_t ipv4_mcast_mask = 0xe0000000;
+		struct sockaddr_in *sa4 = (struct sockaddr_in*)sa;
+		return (ntohl(sa4->sin_addr.s_addr) & ipv4_mcast_mask) == ipv4_mcast_mask;
+	} else if (sa->sa_family == AF_INET6) {
+		struct sockaddr_in6 *sa6 = (struct sockaddr_in6*)sa;
+		return sa6->sin6_addr.s6_addr[0] == 0xff;
+	}
+	return false;
+}
+
+static int make_socket(struct sockaddr_storage *src, socklen_t src_len,
+		struct sockaddr_storage *dst, socklen_t dst_len,
+		bool loop, int ttl)
+{
+	int af, fd, val, res;
+
+	af = src->ss_family;
+	if ((fd = socket(af, SOCK_DGRAM | SOCK_CLOEXEC | SOCK_NONBLOCK, 0)) < 0) {
+		pw_log_error("socket failed: %m");
+		return -errno;
+	}
+	if (bind(fd, (struct sockaddr*)src, src_len) < 0) {
+		res = -errno;
+		pw_log_error("bind() failed: %m");
+		goto error;
+	}
+	if (connect(fd, (struct sockaddr*)dst, dst_len) < 0) {
+		res = -errno;
+		pw_log_error("connect() failed: %m");
+		goto error;
+	}
+	if (is_multicast((struct sockaddr*)dst, dst_len)) {
+		val = loop;
+		if (setsockopt(fd, IPPROTO_IP, IP_MULTICAST_LOOP, &val, sizeof(val)) < 0)
+			pw_log_warn("setsockopt(IP_MULTICAST_LOOP) failed: %m");
+
+		val = ttl;
+		if (setsockopt(fd, IPPROTO_IP, IP_MULTICAST_TTL, &val, sizeof(val)) < 0)
+			pw_log_warn("setsockopt(IP_MULTICAST_TTL) failed: %m");
+	}
+	return fd;
+error:
+	close(fd);
+	return res;
+}
+
+static int get_ip(const struct sockaddr_storage *sa, char *ip, size_t len)
+{
+	if (sa->ss_family == AF_INET) {
+		struct sockaddr_in *in = (struct sockaddr_in*)sa;
+		inet_ntop(sa->ss_family, &in->sin_addr, ip, len);
+	} else if (sa->ss_family == AF_INET6) {
+		struct sockaddr_in6 *in = (struct sockaddr_in6*)sa;
+		inet_ntop(sa->ss_family, &in->sin6_addr, ip, len);
+	} else
+		return -EIO;
+	return 0;
+}
+static void send_sap(struct impl *impl, struct session *sess, bool bye)
+{
+	char buffer[2048], src_addr[64], dst_addr[64], dst_ttl[8];
+	const char *user_name, *af;
+	struct sockaddr *sa = (struct sockaddr*)&impl->src_addr;
+	struct sap_header header;
+	struct iovec iov[4];
+	struct msghdr msg;
+	struct spa_strbuf buf;
+
+	if (!sess->has_sent_sap && bye)
+		return;
+
+	spa_zero(header);
+	header.v = 1;
+	header.t = bye;
+	header.msg_id_hash = sess->msg_id_hash;
+
+	iov[0].iov_base = &header;
+	iov[0].iov_len = sizeof(header);
+
+	if (sa->sa_family == AF_INET) {
+		iov[1].iov_base = &((struct sockaddr_in*) sa)->sin_addr;
+		iov[1].iov_len = 4U;
+		af = "IP4";
+	} else {
+		iov[1].iov_base = &((struct sockaddr_in6*) sa)->sin6_addr;
+		iov[1].iov_len = 16U;
+		header.a = 1;
+		af = "IP6";
+	}
+	iov[2].iov_base = SAP_MIME_TYPE;
+	iov[2].iov_len = sizeof(SAP_MIME_TYPE);
+
+	get_ip(&impl->src_addr, src_addr, sizeof(src_addr));
+	get_ip(&sess->dst_addr, dst_addr, sizeof(dst_addr));
+
+	if ((user_name = pw_get_user_name()) == NULL)
+		user_name = "-";
+
+	spa_zero(dst_ttl);
+	if (is_multicast((struct sockaddr*)&sess->dst_addr, sess->dst_len))
+		snprintf(dst_ttl, sizeof(dst_ttl), "/%d", sess->ttl);
+
+	spa_strbuf_init(&buf, buffer, sizeof(buffer));
+	spa_strbuf_append(&buf,
+			"v=0\n"
+			"o=%s %u 0 IN %s %s\n"
+			"s=%s\n"
+			"c=IN %s %s%s\n"
+			"t=%u 0\n"
+			"a=recvonly\n"
+			"a=tool:PipeWire %s\n"
+			"a=type:broadcast\n",
+			user_name, sess->ntp, af, src_addr,
+			sess->session_name,
+			af, dst_addr, dst_ttl,
+			sess->ntp,
+			pw_get_library_version());
+	spa_strbuf_append(&buf,
+			"m=%s %u RTP/AVP %i\n",
+			sess->media_type,
+			sess->dst_port, sess->payload);
+
+	if (sess->channels) {
+		spa_strbuf_append(&buf,
+			"a=rtpmap:%i %s/%u/%u\n",
+				sess->payload, sess->mime_type,
+				sess->rate, sess->channels);
+	} else {
+		spa_strbuf_append(&buf,
+			"a=rtpmap:%i %s/%u\n",
+				sess->payload, sess->mime_type, sess->rate);
+	}
+	if (sess->ptime != 0)
+		spa_strbuf_append(&buf,
+			"a=ptime:%f\n", sess->ptime);
+
+	if (sess->ts_refclk != NULL) {
+		spa_strbuf_append(&buf,
+				"a=ts-refclk:%s\n"
+				"a=mediaclk:direct=%u\n",
+				sess->ts_refclk,
+				sess->ts_offset);
+	} else {
+		spa_strbuf_append(&buf, "a=mediaclk:sender\n");
+	}
+
+	iov[3].iov_base = buffer;
+	iov[3].iov_len = strlen(buffer);
+
+	msg.msg_name = NULL;
+	msg.msg_namelen = 0;
+	msg.msg_iov = iov;
+	msg.msg_iovlen = 4;
+	msg.msg_control = NULL;
+	msg.msg_controllen = 0;
+	msg.msg_flags = 0;
+
+	sendmsg(impl->sap_fd, &msg, MSG_NOSIGNAL);
+
+	sess->has_sent_sap = true;
+}
+
+static void on_timer_event(void *data, uint64_t expirations)
+{
+	struct impl *impl = data;
+	struct session *sess;
+
+	spa_list_for_each(sess, &impl->sessions, link) {
+		send_sap(impl, sess, 0);
+	}
+}
+
+static int start_sap_announce(struct impl *impl)
+{
+	int fd, res;
+	struct timespec value, interval;
+
+	if ((fd = make_socket(&impl->src_addr, impl->src_len,
+					&impl->sap_addr, impl->sap_len,
+					impl->mcast_loop, impl->ttl)) < 0)
+		return fd;
+
+	impl->sap_fd = fd;
+
+	pw_log_info("starting SAP timer");
+	impl->timer = pw_loop_add_timer(impl->loop, on_timer_event, impl);
+	if (impl->timer == NULL) {
+		res = -errno;
+		pw_log_error("can't create timer source: %m");
+		goto error;
+	}
+	value.tv_sec = 0;
+	value.tv_nsec = 1;
+	interval.tv_sec = SAP_INTERVAL_SEC;
+	interval.tv_nsec = 0;
+	pw_loop_update_timer(impl->loop, impl->timer, &value, &interval, false);
+
+	return 0;
+error:
+	close(fd);
+	return res;
+}
+
+static struct session *session_create(struct impl *impl, struct node *node)
+{
+	struct session *sess = NULL;
+	const char *str;
+	uint32_t port;
+	int res;
+
+	sess = calloc(1, sizeof(struct session));
+	if (sess == NULL)
+		return NULL;
+
+	sess->impl = impl;
+	sess->node = node;
+	sess->msg_id_hash = rand();
+	sess->ntp = (uint32_t) time(NULL) + 2208988800U;
+
+	sess->props = pw_properties_new_dict(node->info->props);
+	if (sess->props == NULL)
+		goto error_free;
+
+	if ((str = pw_properties_get(sess->props, "rtp.session")) != NULL)
+		sess->session_name = strdup(str);
+
+	if ((str = pw_properties_get(sess->props, "rtp.destination.port")) == NULL)
+		goto error_free;
+	if (!spa_atou32(str, &port, 0))
+		goto error_free;
+	sess->dst_port = port;
+
+	if ((str = pw_properties_get(sess->props, "rtp.destination.ip")) == NULL)
+		goto error_free;
+	if ((res = parse_address(str, sess->dst_port, &sess->dst_addr, &sess->dst_len)) < 0) {
+		pw_log_error("invalid destination.ip %s: %s", str, spa_strerror(res));
+		goto error_free;
+	}
+	sess->ttl = pw_properties_get_int32(sess->props, "rtp.ttl", DEFAULT_TTL);
+	sess->payload = pw_properties_get_int32(sess->props, "rtp.payload", 127);
+
+	if ((str = pw_properties_get(sess->props, "rtp.media")) != NULL)
+		sess->media_type = strdup(str);
+	if ((str = pw_properties_get(sess->props, "rtp.mime")) != NULL)
+		sess->mime_type = strdup(str);
+	if ((str = pw_properties_get(sess->props, "rtp.rate")) != NULL)
+		sess->rate = atoi(str);
+	if ((str = pw_properties_get(sess->props, "rtp.channels")) != NULL)
+		sess->channels = atoi(str);
+	if ((str = pw_properties_get(sess->props, "rtp.ts-offset")) != NULL)
+		sess->ts_offset = atoi(str);
+	if ((str = pw_properties_get(sess->props, "rtp.ts-refclk")) != NULL)
+		sess->ts_refclk = strdup(str);
+
+	spa_list_append(&impl->sessions, &sess->link);
+	return sess;
+
+error_free:
+	pw_log_warn("invalid session props");
+	pw_properties_free(sess->props);
+	free(sess->session_name);
+	free(sess);
+	return NULL;
+}
+
+static void session_free(struct session *sess)
+{
+	struct impl *impl = sess->impl;
+
+	send_sap(impl, sess, 1);
+
+	spa_list_remove(&sess->link);
+
+	free(sess->session_name);
+	free(sess);
+}
+
+static void node_event_info(void *data, const struct pw_node_info *info)
+{
+	struct node *n = data;
+	const char *str;
+
+	pw_log_info("node %d added %p", n->id, n->session);
+
+	if (n->session != NULL || info == NULL)
+		return;
+
+	n->info = pw_node_info_merge(n->info, info, true);
+	if (n->info == NULL)
+		return;
+
+	spa_debug_dict(0, info->props);
+
+	if ((str = spa_dict_lookup(info->props, "sess.sap.announce")) == NULL ||
+	    !pw_properties_parse_bool(str))
+		return;
+
+	session_create(n->impl, n);
+}
+
+static const struct pw_node_events node_events = {
+	PW_VERSION_NODE_EVENTS,
+	.info = node_event_info,
+};
+
+static void
+proxy_removed(void *data)
+{
+	struct node *n = data;
+	pw_log_info("node %d removed", n->id);
+	if (n->session != NULL)
+		session_free(n->session);
+	pw_proxy_destroy(n->proxy);
+}
+
+static void
+proxy_destroy(void *data)
+{
+	struct node *n = data;
+	pw_log_info("node %d destroy", n->id);
+	spa_hook_remove(&n->node_listener);
+	spa_hook_remove(&n->proxy_listener);
+	n->proxy = NULL;
+	if (n->info)
+		pw_node_info_free(n->info);
+}
+
+static const struct pw_proxy_events proxy_events = {
+	PW_VERSION_PROXY_EVENTS,
+	.removed = proxy_removed,
+	.destroy = proxy_destroy,
+};
+
+static void registry_event_global(void *data, uint32_t id,
+			uint32_t permissions, const char *type, uint32_t version,
+			const struct spa_dict *props)
+{
+	struct impl *impl = data;
+	struct pw_proxy *proxy;
+	struct node *node;
+
+	if (!spa_streq(type, PW_TYPE_INTERFACE_Node))
+		return;
+
+	proxy = pw_registry_bind(impl->registry, id, type, PW_VERSION_NODE, sizeof(struct node));
+	if (proxy == NULL)
+		return;
+
+	node = pw_proxy_get_user_data(proxy);
+	node->impl = impl;
+	node->id = id;
+	node->proxy = proxy;
+
+	pw_proxy_add_object_listener(proxy,
+			&node->node_listener, &node_events, node);
+        pw_proxy_add_listener(proxy,
+                        &node->proxy_listener, &proxy_events, node);
+}
+
+static const struct pw_registry_events registry_events = {
+	PW_VERSION_REGISTRY_EVENTS,
+	.global = registry_event_global,
+};
+
+static void core_destroy(void *d)
+{
+	struct impl *impl = d;
+	spa_hook_remove(&impl->core_listener);
+	impl->core = NULL;
+	pw_impl_module_schedule_destroy(impl->module);
+}
+
+static const struct pw_proxy_events core_proxy_events = {
+	.destroy = core_destroy,
+};
+
+static void impl_destroy(struct impl *impl)
+{
+	struct session *sess;
+
+	spa_list_consume(sess, &impl->sessions, link)
+		session_free(sess);
+
+	if (impl->registry) {
+		spa_hook_remove(&impl->registry_listener);
+		pw_proxy_destroy((struct pw_proxy*)impl->registry);
+		impl->registry = NULL;
+	}
+	if (impl->core && impl->do_disconnect)
+		pw_core_disconnect(impl->core);
+
+	if (impl->timer)
+		pw_loop_destroy_source(impl->loop, impl->timer);
+
+	if (impl->sap_fd != -1)
+		close(impl->sap_fd);
+
+	pw_properties_free(impl->props);
+
+	free(impl->ifname);
+	free(impl);
+}
+
+static void module_destroy(void *d)
+{
+	struct impl *impl = d;
+	spa_hook_remove(&impl->module_listener);
+	impl_destroy(impl);
+}
+
+static const struct pw_impl_module_events module_events = {
+	PW_VERSION_IMPL_MODULE_EVENTS,
+	.destroy = module_destroy,
+};
+
+static void on_core_error(void *d, uint32_t id, int seq, int res, const char *message)
+{
+	struct impl *impl = d;
+
+	pw_log_error("error id:%u seq:%d res:%d (%s): %s",
+			id, seq, res, spa_strerror(res), message);
+
+	if (id == PW_ID_CORE && res == -EPIPE)
+		pw_impl_module_schedule_destroy(impl->module);
+}
+
+static const struct pw_core_events core_events = {
+	PW_VERSION_CORE_EVENTS,
+	.error = on_core_error,
+};
+
+SPA_EXPORT
+int pipewire__module_init(struct pw_impl_module *module, const char *args)
+{
+	struct pw_context *context = pw_impl_module_get_context(module);
+	struct impl *impl;
+	struct pw_properties *props = NULL;
+	uint32_t port;
+	const char *str;
+	int res = 0;
+
+	PW_LOG_TOPIC_INIT(mod_topic);
+
+	impl = calloc(1, sizeof(struct impl));
+	if (impl == NULL)
+		return -errno;
+
+	impl->sap_fd = -1;
+	spa_list_init(&impl->sessions);
+
+	if (args == NULL)
+		args = "";
+
+	props = pw_properties_new_string(args);
+	if (props == NULL) {
+		res = -errno;
+		pw_log_error( "can't create properties: %m");
+		goto out;
+	}
+	impl->props = props;
+
+	impl->module = module;
+	impl->loop = pw_context_get_main_loop(context);
+
+	str = pw_properties_get(props, "local.ifname");
+	impl->ifname = str ? strdup(str) : NULL;
+
+	if ((str = pw_properties_get(props, "sap.ip")) == NULL)
+		str = DEFAULT_SAP_IP;
+	port = pw_properties_get_uint32(props, "sap.port", DEFAULT_SAP_PORT);
+	if ((res = parse_address(str, port, &impl->sap_addr, &impl->sap_len)) < 0) {
+		pw_log_error("invalid sap.ip %s: %s", str, spa_strerror(res));
+		goto out;
+	}
+
+	if ((str = pw_properties_get(props, "source.ip")) == NULL)
+		str = DEFAULT_SOURCE_IP;
+	if ((res = parse_address(str, 0, &impl->src_addr, &impl->src_len)) < 0) {
+		pw_log_error("invalid source.ip %s: %s", str, spa_strerror(res));
+		goto out;
+	}
+
+	impl->ttl = pw_properties_get_uint32(props, "net.ttl", DEFAULT_TTL);
+	impl->mcast_loop = pw_properties_get_bool(props, "net.loop", DEFAULT_LOOP);
+
+	impl->core = pw_context_get_object(context, PW_TYPE_INTERFACE_Core);
+	if (impl->core == NULL) {
+		str = pw_properties_get(props, PW_KEY_REMOTE_NAME);
+		impl->core = pw_context_connect(context,
+				pw_properties_new(
+					PW_KEY_REMOTE_NAME, str,
+					NULL),
+				0);
+		impl->do_disconnect = true;
+	}
+	if (impl->core == NULL) {
+		res = -errno;
+		pw_log_error("can't connect: %m");
+		goto out;
+	}
+
+	pw_proxy_add_listener((struct pw_proxy*)impl->core,
+			&impl->core_proxy_listener,
+			&core_proxy_events, impl);
+	pw_core_add_listener(impl->core,
+			&impl->core_listener,
+			&core_events, impl);
+
+	if ((res = start_sap_announce(impl)) < 0)
+		goto out;
+
+	impl->registry = pw_core_get_registry(impl->core, PW_VERSION_REGISTRY, 0);
+	pw_registry_add_listener(impl->registry, &impl->registry_listener,
+			&registry_events, impl);
+
+	pw_impl_module_add_listener(module, &impl->module_listener, &module_events, impl);
+
+	pw_impl_module_update_properties(module, &SPA_DICT_INIT_ARRAY(module_info));
+
+	pw_log_info("Successfully loaded module-rtp-sink");
+
+	return 0;
+out:
+	impl_destroy(impl);
+	return res;
+}