1 files changed, 565 insertions, 0 deletions

diff --git a/src/modules/module-zeroconf-discover.c b/src/modules/module-zeroconf-discover.c
new file mode 100644
index 0000000..5e7436f
--- /dev/null
+++ b/src/modules/module-zeroconf-discover.c
@@ -0,0 +1,565 @@
+/* PipeWire
+ *
+ * Copyright © 2021 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 "config.h"
+
+#include <spa/utils/result.h>
+#include <spa/utils/string.h>
+#include <spa/utils/json.h>
+#include <spa/param/audio/format-utils.h>
+
+#include <pipewire/impl.h>
+#include <pipewire/i18n.h>
+
+#include <avahi-client/lookup.h>
+#include <avahi-common/error.h>
+#include <avahi-common/malloc.h>
+
+#include "module-protocol-pulse/format.h"
+#include "module-zeroconf-discover/avahi-poll.h"
+
+/** \page page_module_zeroconf_discover PipeWire Module: Zeroconf Discover
+ *
+ * Use zeroconf to detect and load module-pulse-tunnel with the right
+ * parameters. This will automatically create sinks and sources to stream
+ * audio to/from remote PulseAudio servers. It also works with
+ * module-protocol-pulse.
+ *
+ * ## Module Options
+ *
+ * - `pulse.latency`: the latency to end-to-end latency in milliseconds to
+ *                    maintain (Default 200ms).
+ *
+ * ## Example configuration
+ *
+ *\code{.unparsed}
+ * context.modules = [
+ * {   name = libpipewire-module-zeroconf-discover
+ *     args = { }
+ * }
+ * ]
+ *\endcode
+ */
+
+#define NAME "zeroconf-discover"
+
+PW_LOG_TOPIC_STATIC(mod_topic, "mod." NAME);
+#define PW_LOG_TOPIC_DEFAULT mod_topic
+
+#define MODULE_USAGE	"pulse.latency=<latency in msec> "
+
+static const struct spa_dict_item module_props[] = {
+	{ PW_KEY_MODULE_AUTHOR, "Wim Taymans <wim.taymans@gmail.com>" },
+	{ PW_KEY_MODULE_DESCRIPTION, "Discover remote streams" },
+	{ PW_KEY_MODULE_USAGE, MODULE_USAGE },
+	{ PW_KEY_MODULE_VERSION, PACKAGE_VERSION },
+};
+
+#define SERVICE_TYPE_SINK "_pulse-sink._tcp"
+#define SERVICE_TYPE_SOURCE "_non-monitor._sub._pulse-source._tcp"
+
+
+struct impl {
+	struct pw_context *context;
+
+	struct pw_impl_module *module;
+	struct spa_hook module_listener;
+
+	struct pw_properties *properties;
+
+	AvahiPoll *avahi_poll;
+	AvahiClient *client;
+	AvahiServiceBrowser *sink_browser;
+	AvahiServiceBrowser *source_browser;
+
+	struct spa_list tunnel_list;
+};
+
+struct tunnel_info {
+	AvahiIfIndex interface;
+	AvahiProtocol protocol;
+	const char *name;
+	const char *type;
+	const char *domain;
+};
+
+#define TUNNEL_INFO(...) ((struct tunnel_info){ __VA_ARGS__ })
+
+struct tunnel {
+	struct spa_list link;
+	struct tunnel_info info;
+	struct pw_impl_module *module;
+	struct spa_hook module_listener;
+};
+
+static int start_client(struct impl *impl);
+
+static struct tunnel *make_tunnel(struct impl *impl, const struct tunnel_info *info)
+{
+	struct tunnel *t;
+
+	t = calloc(1, sizeof(*t));
+	if (t == NULL)
+		return NULL;
+
+	t->info.interface = info->interface;
+	t->info.protocol = info->protocol;
+	t->info.name = strdup(info->name);
+	t->info.type = strdup(info->type);
+	t->info.domain = strdup(info->domain);
+	spa_list_append(&impl->tunnel_list, &t->link);
+
+	return t;
+}
+
+static struct tunnel *find_tunnel(struct impl *impl, const struct tunnel_info *info)
+{
+	struct tunnel *t;
+	spa_list_for_each(t, &impl->tunnel_list, link) {
+		if (t->info.interface == info->interface &&
+		    t->info.protocol == info->protocol &&
+		    spa_streq(t->info.name, info->name) &&
+		    spa_streq(t->info.type, info->type) &&
+		    spa_streq(t->info.domain, info->domain))
+			return t;
+	}
+	return NULL;
+}
+
+static void free_tunnel(struct tunnel *t)
+{
+	pw_impl_module_destroy(t->module);
+}
+
+static void impl_free(struct impl *impl)
+{
+	struct tunnel *t;
+
+	spa_list_consume(t, &impl->tunnel_list, link)
+		free_tunnel(t);
+
+	if (impl->sink_browser)
+		avahi_service_browser_free(impl->sink_browser);
+	if (impl->source_browser)
+		avahi_service_browser_free(impl->source_browser);
+	if (impl->client)
+		avahi_client_free(impl->client);
+	if (impl->avahi_poll)
+		pw_avahi_poll_free(impl->avahi_poll);
+	pw_properties_free(impl->properties);
+	free(impl);
+}
+
+static void module_destroy(void *data)
+{
+	struct impl *impl = data;
+	spa_hook_remove(&impl->module_listener);
+	impl_free(impl);
+}
+
+static const struct pw_impl_module_events module_events = {
+	PW_VERSION_IMPL_MODULE_EVENTS,
+	.destroy = module_destroy,
+};
+
+static void pw_properties_from_avahi_string(const char *key, const char *value,
+		struct pw_properties *props)
+{
+	if (spa_streq(key, "device")) {
+		pw_properties_set(props, PW_KEY_TARGET_OBJECT, value);
+	}
+	else if (spa_streq(key, "rate")) {
+		pw_properties_set(props, PW_KEY_AUDIO_RATE, value);
+	}
+	else if (spa_streq(key, "channels")) {
+		pw_properties_set(props, PW_KEY_AUDIO_CHANNELS, value);
+	}
+	else if (spa_streq(key, "channel_map")) {
+		struct channel_map channel_map;
+		uint32_t i, pos[CHANNELS_MAX];
+		char *p, *s;
+
+		spa_zero(channel_map);
+		channel_map_parse(value, &channel_map);
+		channel_map_to_positions(&channel_map, pos);
+
+		p = s = alloca(4 + channel_map.channels * 8);
+		p += spa_scnprintf(p, 2, "[");
+		for (i = 0; i < channel_map.channels; i++)
+			p += spa_scnprintf(p, 8, "%s%s", i == 0 ? "" : ",",
+				channel_id2name(pos[i]));
+		p += spa_scnprintf(p, 2, "]");
+		pw_properties_set(props, SPA_KEY_AUDIO_POSITION, s);
+	}
+	else if (spa_streq(key, "format")) {
+		uint32_t fmt = format_paname2id(value, strlen(value));
+		if (fmt != SPA_AUDIO_FORMAT_UNKNOWN)
+			pw_properties_set(props, PW_KEY_AUDIO_FORMAT, format_id2name(fmt));
+	}
+	else if (spa_streq(key, "icon-name")) {
+		pw_properties_set(props, PW_KEY_DEVICE_ICON_NAME, value);
+	}
+	else if (spa_streq(key, "product-name")) {
+		pw_properties_set(props, PW_KEY_DEVICE_PRODUCT_NAME, value);
+	}
+	else if (spa_streq(key, "description")) {
+		pw_properties_set(props, "tunnel.remote.description", value);
+	}
+	else if (spa_streq(key, "fqdn")) {
+		pw_properties_set(props, "tunnel.remote.fqdn", value);
+	}
+	else if (spa_streq(key, "user-name")) {
+		pw_properties_set(props, "tunnel.remote.user", value);
+	}
+}
+
+static void submodule_destroy(void *data)
+{
+	struct tunnel *t = data;
+
+	spa_list_remove(&t->link);
+	spa_hook_remove(&t->module_listener);
+
+	free((char *) t->info.name);
+	free((char *) t->info.type);
+	free((char *) t->info.domain);
+
+	free(t);
+}
+
+static const struct pw_impl_module_events submodule_events = {
+	PW_VERSION_IMPL_MODULE_EVENTS,
+	.destroy = submodule_destroy,
+};
+
+static void resolver_cb(AvahiServiceResolver *r, AvahiIfIndex interface, AvahiProtocol protocol,
+	AvahiResolverEvent event, const char *name, const char *type, const char *domain,
+	const char *host_name, const AvahiAddress *a, uint16_t port, AvahiStringList *txt,
+	AvahiLookupResultFlags flags, void *userdata)
+{
+	struct impl *impl = userdata;
+	struct tunnel *t;
+	struct tunnel_info tinfo;
+	const char *str, *device, *desc, *fqdn, *user;
+	char if_suffix[16] = "";
+	char at[AVAHI_ADDRESS_STR_MAX];
+	AvahiStringList *l;
+	FILE *f;
+	char *args;
+	size_t size;
+	struct pw_impl_module *mod;
+	struct pw_properties *props = NULL;
+
+	if (event != AVAHI_RESOLVER_FOUND) {
+		pw_log_error("Resolving of '%s' failed: %s", name,
+				avahi_strerror(avahi_client_errno(impl->client)));
+		goto done;
+	}
+	tinfo = TUNNEL_INFO(.interface = interface,
+			.protocol = protocol,
+			.name = name,
+			.type = type,
+			.domain = domain);
+
+	props = pw_properties_new(NULL, NULL);
+	if (props == NULL) {
+		pw_log_error("Can't allocate properties: %m");
+		goto done;
+	}
+
+	for (l = txt; l; l = l->next) {
+		char *key, *value;
+
+		if (avahi_string_list_get_pair(l, &key, &value, NULL) != 0)
+			break;
+
+		pw_properties_from_avahi_string(key, value, props);
+		avahi_free(key);
+		avahi_free(value);
+	}
+
+	if ((device = pw_properties_get(props, PW_KEY_TARGET_OBJECT)) != NULL)
+		pw_properties_setf(props, PW_KEY_NODE_NAME,
+				"tunnel.%s.%s", host_name, device);
+	else
+		pw_properties_setf(props, PW_KEY_NODE_NAME,
+				"tunnel.%s", host_name);
+
+	str = strstr(type, "sink") ? "sink" : "source";
+	pw_properties_set(props, "tunnel.mode", str);
+
+	if (a->proto == AVAHI_PROTO_INET6 &&
+	    a->data.ipv6.address[0] == 0xfe &&
+	    (a->data.ipv6.address[1] & 0xc0) == 0x80)
+		snprintf(if_suffix, sizeof(if_suffix), "%%%d", interface);
+
+	pw_properties_setf(props, "pulse.server.address", " [%s%s]:%u",
+			avahi_address_snprint(at, sizeof(at), a),
+			if_suffix, port);
+
+	desc = pw_properties_get(props, "tunnel.remote.description");
+	if (desc == NULL)
+		desc = pw_properties_get(props, PW_KEY_DEVICE_PRODUCT_NAME);
+	if (desc == NULL)
+		desc = pw_properties_get(props, PW_KEY_TARGET_OBJECT);
+	if (desc == NULL)
+		desc = _("Unknown device");
+
+	fqdn = pw_properties_get(props, "tunnel.remote.fqdn");
+	if (fqdn == NULL)
+		fqdn = pw_properties_get(props, "pulse.server.address");
+	if (fqdn == NULL)
+		fqdn = host_name;
+
+	user = pw_properties_get(props, "tunnel.remote.user");
+
+	if (desc != NULL && user != NULL && fqdn != NULL) {
+		pw_properties_setf(props, PW_KEY_NODE_DESCRIPTION,
+				_("%s on %s@%s"), desc, user, fqdn);
+	}
+	else if (desc != NULL && fqdn != NULL) {
+		pw_properties_setf(props, PW_KEY_NODE_DESCRIPTION,
+				_("%s on %s"), desc, fqdn);
+	}
+
+	if ((str = pw_properties_get(impl->properties, "pulse.latency")) != NULL)
+		pw_properties_set(props, "pulse.latency", str);
+
+	if ((f = open_memstream(&args, &size)) == NULL) {
+		pw_log_error("Can't open memstream: %m");
+		goto done;
+	}
+
+	fprintf(f, "{");
+	pw_properties_serialize_dict(f, &props->dict, 0);
+	fprintf(f, " stream.props = {");
+	fprintf(f, " }");
+	fprintf(f, "}");
+        fclose(f);
+
+	pw_properties_free(props);
+
+	pw_log_info("loading module args:'%s'", args);
+	mod = pw_context_load_module(impl->context,
+			"libpipewire-module-pulse-tunnel",
+			args, NULL);
+	free(args);
+
+	if (mod == NULL) {
+		pw_log_error("Can't load module: %m");
+                goto done;
+	}
+
+	t = make_tunnel(impl, &tinfo);
+	if (t == NULL) {
+		pw_log_error("Can't make tunnel: %m");
+		pw_impl_module_destroy(mod);
+		goto done;
+	}
+
+	pw_impl_module_add_listener(mod, &t->module_listener, &submodule_events, t);
+
+	t->module = mod;
+
+done:
+	avahi_service_resolver_free(r);
+}
+
+
+static void browser_cb(AvahiServiceBrowser *b, AvahiIfIndex interface, AvahiProtocol protocol,
+	AvahiBrowserEvent event, const char *name, const char *type, const char *domain,
+	AvahiLookupResultFlags flags, void *userdata)
+{
+	struct impl *impl = userdata;
+	struct tunnel_info info;
+	struct tunnel *t;
+
+	if (flags & AVAHI_LOOKUP_RESULT_LOCAL)
+		return;
+
+	info = TUNNEL_INFO(.interface = interface,
+			.protocol = protocol,
+			.name = name,
+			.type = type,
+			.domain = domain);
+
+	t = find_tunnel(impl, &info);
+
+	switch (event) {
+	case AVAHI_BROWSER_NEW:
+		if (t != NULL)
+			return;
+		if (!(avahi_service_resolver_new(impl->client,
+						interface, protocol,
+						name, type, domain,
+						AVAHI_PROTO_UNSPEC, 0,
+						resolver_cb, impl)))
+			pw_log_error("can't make service resolver: %s",
+					avahi_strerror(avahi_client_errno(impl->client)));
+		break;
+	case AVAHI_BROWSER_REMOVE:
+		if (t == NULL)
+			return;
+		free_tunnel(t);
+		break;
+	default:
+		break;
+	}
+}
+
+
+static struct AvahiServiceBrowser *make_browser(struct impl *impl, const char *service_type)
+{
+	struct AvahiServiceBrowser *s;
+
+	s = avahi_service_browser_new(impl->client,
+                              AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC,
+                              service_type, NULL, 0,
+                              browser_cb, impl);
+	if (s == NULL) {
+		pw_log_error("can't make browser for %s: %s", service_type,
+				avahi_strerror(avahi_client_errno(impl->client)));
+	}
+	return s;
+}
+
+static void client_callback(AvahiClient *c, AvahiClientState state, void *userdata)
+{
+	struct impl *impl = userdata;
+
+	impl->client = c;
+
+	switch (state) {
+	case AVAHI_CLIENT_S_REGISTERING:
+	case AVAHI_CLIENT_S_RUNNING:
+	case AVAHI_CLIENT_S_COLLISION:
+		if (impl->sink_browser == NULL)
+			impl->sink_browser = make_browser(impl, SERVICE_TYPE_SINK);
+		if (impl->sink_browser == NULL)
+			goto error;
+
+		if (impl->source_browser == NULL)
+			impl->source_browser = make_browser(impl, SERVICE_TYPE_SOURCE);
+		if (impl->source_browser == NULL)
+			goto error;
+
+		break;
+	case AVAHI_CLIENT_FAILURE:
+		if (avahi_client_errno(c) == AVAHI_ERR_DISCONNECTED)
+			start_client(impl);
+
+		SPA_FALLTHROUGH;
+	case AVAHI_CLIENT_CONNECTING:
+		if (impl->sink_browser) {
+			avahi_service_browser_free(impl->sink_browser);
+			impl->sink_browser = NULL;
+		}
+		if (impl->source_browser) {
+			avahi_service_browser_free(impl->source_browser);
+			impl->source_browser = NULL;
+		}
+		break;
+	default:
+		break;
+	}
+	return;
+error:
+	pw_impl_module_schedule_destroy(impl->module);
+}
+
+static int start_client(struct impl *impl)
+{
+	int res;
+	if ((impl->client = avahi_client_new(impl->avahi_poll,
+					AVAHI_CLIENT_NO_FAIL,
+					client_callback, impl,
+					&res)) == NULL) {
+		pw_log_error("can't create client: %s", avahi_strerror(res));
+		pw_impl_module_schedule_destroy(impl->module);
+		return -EIO;
+	}
+	return 0;
+}
+
+static int start_avahi(struct impl *impl)
+{
+	struct pw_loop *loop;
+
+	loop = pw_context_get_main_loop(impl->context);
+	impl->avahi_poll = pw_avahi_poll_new(loop);
+
+	return start_client(impl);
+}
+
+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 pw_properties *props;
+	struct impl *impl;
+	int res;
+
+	PW_LOG_TOPIC_INIT(mod_topic);
+
+	impl = calloc(1, sizeof(struct impl));
+	if (impl == NULL)
+		goto error_errno;
+
+	pw_log_debug("module %p: new %s", impl, args);
+
+	if (args == NULL)
+		args = "";
+
+	props = pw_properties_new_string(args);
+	if (props == NULL)
+		goto error_errno;
+
+	spa_list_init(&impl->tunnel_list);
+
+	impl->module = module;
+	impl->context = context;
+	impl->properties = props;
+
+	pw_impl_module_add_listener(module, &impl->module_listener, &module_events, impl);
+
+	pw_impl_module_update_properties(module, &SPA_DICT_INIT_ARRAY(module_props));
+
+	start_avahi(impl);
+
+	return 0;
+
+error_errno:
+	res = -errno;
+	if (impl)
+		impl_free(impl);
+	return res;
+}