From: Gerrit Renker <grenker@cscs.ch>
Date: Sun, 23 May 2010 05:43:04 +0000 (+0200)
Subject: udp: integrate new fec interaction
X-Git-Tag: v0.4.3~13^2~11
X-Git-Url: http://git.tue.mpg.de/?a=commitdiff_plain;h=34d059caa24a68c2e420050ce3a67d32ce3fbdea;p=paraslash.git

udp: integrate new fec interaction

This patch implements the new UDP-FEC interface in two steps:
 (1) updating the UDP sender analogously to the previous (DCCP sender) patch;
 (2) unifying the struct udp_target by factoring out the fields it has in
     common with 'struct sender_client'.

The open() function is deferred to a subsequent patch. The user can override
the MPS value by supplying a max_slice_bytes value not larger than the MPS.
---

diff --git a/udp_send.c b/udp_send.c
index 478c5d9f..5c1cdf02 100644
--- a/udp_send.c
+++ b/udp_send.c
@@ -33,16 +33,12 @@
 
 /** Describes one entry in the list of targets for the udp sender. */
 struct udp_target {
-	/** The position of this target in the list of targets. */
-	struct list_head node;
 	/** The hostname (DNS name or IPv4/v6 address string). */
 	char host[MAX_HOSTLEN];
 	/** The UDP port. */
 	int port;
-	/** The socket fd. */
-	int fd;
-	/** The list of queued chunks for this fd. */
-	struct chunk_queue *cq;
+	/** Common sender client data */
+	struct sender_client *sc;
 	/** The opaque structure returned by vss_add_fec_client(). */
 	struct fec_client *fc;
 	/** The FEC parameters for this target. */
@@ -51,40 +47,41 @@ struct udp_target {
 
 static struct list_head targets;
 static int sender_status;
-static struct sender *self;
 
-static void udp_close_target(struct udp_target *ut)
+static void udp_close_target(struct sender_client *sc)
 {
-	if (ut->fd < 0)
+	if (sc->fd < 0)
 		return;
-	close(ut->fd);
-	del_close_on_fork_list(ut->fd);
-	cq_destroy(ut->cq);
-	ut->cq = NULL;
-	ut->fd = -1;
+	close(sc->fd);
+	del_close_on_fork_list(sc->fd);
+	cq_destroy(sc->cq);
+	sc->cq	 = NULL;
+	sc->fd	 = -1;
 }
 
 static void udp_delete_target(struct udp_target *ut, const char *msg)
 {
+
 	PARA_NOTICE_LOG("deleting %s#%d (%s) from list\n", ut->host,
 		ut->port, msg);
-	udp_close_target(ut);
+	udp_close_target(ut->sc);
 	vss_del_fec_client(ut->fc);
-	list_del(&ut->node);
+	list_del(&ut->sc->node);
+	free(ut->sc);
 	free(ut);
 }
 
 /**
  * Perform AF-independent multicast sender setup.
  *
- * \param fd	The connected socket descriptor.
+ * \param sc	The connected sender client.
  * \param ttl	UDPv4 multicast TTL or UDPv6 multicast number of hops.
  *		Use -1 to mean default, 0..255 otherwise.
  * \param iface	The outgoing multicast interface, or NULL for the default.
  *
  * \return Zero if okay, negative on error.
  */
-static int mcast_sender_setup(struct udp_target *ut, int ttl, char *iface)
+static int mcast_sender_setup(struct sender_client *sc, int ttl, char *iface)
 {
 	struct sockaddr_storage ss;
 	socklen_t sslen = sizeof(ss);
@@ -92,7 +89,7 @@ static int mcast_sender_setup(struct udp_target *ut, int ttl, char *iface)
 	const int on = 1;
 	int id = iface == NULL ? 0 : if_nametoindex(iface);
 
-	if (getpeername(ut->fd, (struct sockaddr *)&ss, &sslen) < 0)
+	if (getpeername(sc->fd, (struct sockaddr *)&ss, &sslen) < 0)
 		goto err;
 
 	if (iface != NULL && id == 0)
@@ -112,7 +109,7 @@ static int mcast_sender_setup(struct udp_target *ut, int ttl, char *iface)
 
 			memset(&mn, 0, sizeof(mn));
 			mn.imr_ifindex = id;
-			if (setsockopt(ut->fd, IPPROTO_IP, IP_MULTICAST_IF, &mn, sizeof(mn)) < 0)
+			if (setsockopt(sc->fd, IPPROTO_IP, IP_MULTICAST_IF, &mn, sizeof(mn)) < 0)
 				goto err;
 #else
 			PARA_ERROR_LOG("No support for setting outgoing IPv4 mcast interface.");
@@ -122,24 +119,24 @@ static int mcast_sender_setup(struct udp_target *ut, int ttl, char *iface)
 		 * Enable receiving multicast messages generated on the local host
 		 * At least on Linux, this is enabled by default.
 		 */
-		if (setsockopt(ut->fd, IPPROTO_IP, IP_MULTICAST_LOOP, &on, sizeof(on)) < 0)
+		if (setsockopt(sc->fd, IPPROTO_IP, IP_MULTICAST_LOOP, &on, sizeof(on)) < 0)
 			break;
 
 		/* Default: use local subnet (do not flood out into the WAN) */
 		if (ttl == -1)
 			ttl = 1;
-		if (setsockopt(ut->fd, IPPROTO_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl)) < 0)
+		if (setsockopt(sc->fd, IPPROTO_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl)) < 0)
 			break;
 		return 0;
 	case AF_INET6:
 		if (!IN6_IS_ADDR_MULTICAST(&((struct sockaddr_in6 *)&ss)->sin6_addr))
 			return 0;
 		if (id != 0 &&
-		    setsockopt(ut->fd, IPPROTO_IPV6, IPV6_MULTICAST_IF, &id, sizeof(id)) < 0)
+		    setsockopt(sc->fd, IPPROTO_IPV6, IPV6_MULTICAST_IF, &id, sizeof(id)) < 0)
 			break;
-		if (setsockopt(ut->fd, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &on, sizeof(on)) < 0)
+		if (setsockopt(sc->fd, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &on, sizeof(on)) < 0)
 			break;
-		if (setsockopt(ut->fd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &ttl, sizeof(ttl)) < 0)
+		if (setsockopt(sc->fd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &ttl, sizeof(ttl)) < 0)
 			break;
 		return 0;
 	default:
@@ -153,57 +150,55 @@ err:
 /** The maximal size of the per-target chunk queue. */
 #define UDP_CQ_BYTES 40000
 
-static int udp_open(void *client, struct fec_client_parms **fcp)
+static int udp_init_session(struct sender_client *sc)
 {
-	struct udp_target *ut = client;
+	struct udp_target *ut = sc->private_data;
 	int ret;
 	char *iface = NULL;
 
-	if (ut->fd >= 0) /* nothing to do */
+	if (sc->fd >= 0) /* nothing to do */
 		return 0;
 
 	ret = para_connect_simple(IPPROTO_UDP, ut->host, ut->port);
 	if (ret < 0)
 		return ret;
-	ut->fd = ret;
+	sc->fd = ret;
 
 	if (conf.udp_mcast_iface_given)
 		iface = conf.udp_mcast_iface_arg;
 
-	ret = mcast_sender_setup(ut, conf.udp_ttl_arg, iface);
+	ret = mcast_sender_setup(sc, conf.udp_ttl_arg, iface);
 	if (ret < 0) {
-		close(ut->fd);
+		close(sc->fd);
 		return ret;
 	}
 
-	ret = mark_fd_nonblocking(ut->fd);
+	ret = mark_fd_nonblocking(sc->fd);
 	if (ret < 0) {
-		close(ut->fd);
+		close(sc->fd);
 		return ret;
 	}
-	add_close_on_fork_list(ut->fd);
-	ut->cq = cq_new(UDP_CQ_BYTES);
-	ut->fcp.max_slice_bytes = 1472; /* FIXME */
-	*fcp = &ut->fcp;
+	add_close_on_fork_list(sc->fd);
+	sc->cq   = cq_new(UDP_CQ_BYTES);
 	PARA_NOTICE_LOG("sending to udp %s#%d\n", ut->host, ut->port);
 	return 1;
 }
 
 static void udp_shutdown_targets(void)
 {
-	struct udp_target *ut, *tmp;
+	struct sender_client *sc, *tmp;
 	const char *buf = NULL;
 	size_t len = 0; /* STFU, gcc */
 
-	list_for_each_entry_safe(ut, tmp, &targets, node) {
+	list_for_each_entry_safe(sc, tmp, &targets, node) {
 		int ubuntu_glibc_headers_suck;
-		if (ut->fd < 0)
+		if (sc->fd < 0)
 			continue;
 		if (!buf)
 			len = vss_get_fec_eof_packet(&buf);
 		/* ignore return value, we're closing the target anyway. */
-		ubuntu_glibc_headers_suck = write(ut->fd, buf, len); /* STFU */
-		udp_close_target(ut);
+		ubuntu_glibc_headers_suck = write(sc->fd, buf, len); /* STFU */
+		udp_close_target(sc);
 	}
 }
 
@@ -222,9 +217,11 @@ static int udp_com_off(__a_unused struct sender_command_data *scd)
 
 static int udp_com_delete(struct sender_command_data *scd)
 {
-	struct udp_target *ut, *tmp;
+	struct sender_client *sc, *tmp;
+
+	list_for_each_entry_safe(sc, tmp, &targets, node) {
+		struct udp_target *ut = sc->private_data;
 
-	list_for_each_entry_safe(ut, tmp, &targets, node) {
 		/* Unspecified port means wildcard port match */
 		if (scd->port > 0 && scd->port != ut->port)
 			continue;
@@ -235,14 +232,17 @@ static int udp_com_delete(struct sender_command_data *scd)
 	return 1;
 }
 
-static int udp_send_fec(char *buf, size_t len, void *private_data)
+static int udp_send_fec(struct sender_client *sc, char *buf, size_t len)
 {
-	struct udp_target *ut = private_data;
+	struct udp_target *ut = sc->private_data;
 	int ret;
 
 	if (sender_status == SENDER_OFF)
 		return 0;
-	ret = send_queued_chunks(ut->fd, ut->cq, 0);
+	ret = udp_init_session(sc);
+	if (ret < 0)
+		goto fail;
+	ret = send_queued_chunks(sc->fd, sc->cq, 0);
 	if (ret == -ERRNO_TO_PARA_ERROR(ECONNREFUSED))
 		ret = 0;
 	if (ret < 0)
@@ -250,16 +250,16 @@ static int udp_send_fec(char *buf, size_t len, void *private_data)
 	if (!len)
 		return 0;
 	if (!ret) { /* still data left in the queue */
-		ret = cq_force_enqueue(ut->cq, buf, len);
+		ret = cq_force_enqueue(sc->cq, buf, len);
 		assert(ret >= 0);
 	}
-	ret = write_nonblock(ut->fd, buf, len, 0);
+	ret = write_nonblock(sc->fd, buf, len, 0);
 	if (ret == -ERRNO_TO_PARA_ERROR(ECONNREFUSED))
 		ret = 0;
 	if (ret < 0)
 		goto fail;
 	if (ret != len) {
-		ret = cq_force_enqueue(ut->cq, buf + ret, len - ret);
+		ret = cq_force_enqueue(sc->cq, buf + ret, len - ret);
 		assert(ret >= 0);
 	}
 	return 1;
@@ -270,16 +270,24 @@ fail:
 
 static void udp_add_target(struct sender_command_data *scd)
 {
-	struct udp_target *ut = para_calloc(sizeof(struct udp_target));
+	struct udp_target *ut = para_calloc(sizeof(*ut));
 
 	strncpy(ut->host, scd->host, sizeof(ut->host));
 	ut->port = scd->port > 0 ? scd->port : conf.udp_default_port_arg;
-	ut->fd = -1; /* not yet connected */
-	PARA_INFO_LOG("adding to target list (%s#%d)\n", ut->host, ut->port);
-	para_list_add(&ut->node, &targets);
-	ut->fcp.slices_per_group = scd->slices_per_group;
+
+	ut->fcp.slices_per_group      = scd->slices_per_group;
 	ut->fcp.data_slices_per_group = scd->data_slices_per_group;
-	/* XXX RESOLVED LATER vss_add_fec_client(self, ut, &ut->fc); */
+	ut->fcp.max_slice_bytes	      = scd->max_slice_bytes;
+	ut->fcp.init_fec	      = NULL; /* FIXME */
+	ut->fcp.send_fec	      = udp_send_fec;
+
+	ut->sc = para_calloc(sizeof(*ut->sc));
+	ut->sc->fd = -1; /* not yet connected */
+	ut->sc->private_data = ut;
+	ut->fc = vss_add_fec_client(ut->sc, &ut->fcp);
+
+	PARA_INFO_LOG("adding to target list (%s#%d)\n", ut->host, ut->port);
+	para_list_add(&ut->sc->node, &targets);
 }
 
 static int udp_com_add(struct sender_command_data *scd)
@@ -290,10 +298,11 @@ static int udp_com_add(struct sender_command_data *scd)
 
 static char *udp_info(void)
 {
-	struct udp_target *ut;
+	struct sender_client *sc;
 	char *ret, *tgts = NULL;
 
-	list_for_each_entry(ut, &targets, node) {
+	list_for_each_entry(sc, &targets, node) {
+		struct udp_target *ut = sc->private_data;
 		bool is_v6 = strchr(ut->host, ':') != NULL;
 		char *tmp = make_message("%s%s%s%s:%d/%u:%u:%u ", tgts ? : "",
 			is_v6 ? "[" : "", ut->host,
@@ -364,8 +373,6 @@ void udp_send_init(struct sender *s)
 	s->info = udp_info;
 	s->help = udp_help;
 	s->send = NULL;
-	s->send_fec = udp_send_fec;
-	s->open = udp_open;
 	s->pre_select = NULL;
 	s->post_select = NULL;
 	s->shutdown_clients = udp_shutdown_targets;
@@ -379,6 +386,5 @@ void udp_send_init(struct sender *s)
 	udp_init_target_list();
 	if (!conf.udp_no_autostart_given)
 		sender_status = SENDER_ON;
-	self = s;
 	PARA_DEBUG_LOG("udp sender init complete\n");
 }