#include "close_on_fork.h"
#include "chunk_queue.h"
+/**
+ * Time window during which ICMP Destination/Port Unreachable messages are
+ * ignored, covering transient receiver problems such as restarting the
+ * client, rebooting, reconfiguration, or handover.
+ */
+#define UDP_MAX_UNREACHABLE_TIME 30
+
/** Describes one entry in the list of targets for the udp sender. */
struct udp_target {
- /** The hostname (DNS name or IPv4/v6 address string). */
- char host[MAX_HOSTLEN];
- /** The UDP port. */
- int port;
+ /** Track time (seconds) of last ICMP Port Unreachable error */
+ time_t last_unreachable;
/** Common sender client data */
struct sender_client *sc;
/** The opaque structure returned by vss_add_fec_client(). */
if (sc->cq != NULL) {
del_close_on_fork_list(sc->fd);
cq_destroy(sc->cq);
- free(sc->name);
- sc->name = NULL;
sc->cq = NULL;
-
}
}
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);
+ PARA_NOTICE_LOG("deleting %s (%s) from list\n", ut->sc->name, msg);
udp_close_target(ut->sc);
vss_del_fec_client(ut->fc);
list_del(&ut->sc->node);
+ free(ut->sc->name);
free(ut->sc);
free(ut);
}
static void udp_init_session(struct sender_client *sc)
{
if (sc->cq == NULL) {
+ sc->cq = cq_new(UDP_CQ_BYTES);
add_close_on_fork_list(sc->fd);
- sc->cq = cq_new(UDP_CQ_BYTES);
- sc->name = para_strdup(remote_name(sc->fd));
PARA_NOTICE_LOG("sending to udp %s\n", sc->name);
}
}
}
}
+static int udp_resolve_target(const char *url, struct sender_command_data *scd)
+{
+ const char *result;
+ int ret, port;
+
+ ret = parse_fec_url(url, scd);
+ if (ret)
+ return ret;
+ port = scd->port > 0 ? scd->port : conf.udp_default_port_arg;
+
+ ret = para_connect_simple(IPPROTO_UDP, scd->host, port);
+ if (ret < 0)
+ return ret;
+
+ result = remote_name(ret);
+ close(ret);
+
+ if (!parse_url(result, scd->host, sizeof(scd->host), &scd->port))
+ return -E_ADDRESS_LOOKUP;
+ return 1;
+}
+
static int udp_com_on(__a_unused struct sender_command_data *scd)
{
sender_status = SENDER_ON;
return 1;
}
-static int udp_com_delete(struct sender_command_data *scd)
+static struct sender_client *udp_lookup_target(struct sender_command_data *scd)
{
struct sender_client *sc, *tmp;
+ char host[MAX_HOSTLEN];
+ int32_t port;
list_for_each_entry_safe(sc, tmp, &targets, node) {
- struct udp_target *ut = sc->private_data;
+ parse_url(sc->name, host, sizeof(host), &port);
/* Unspecified port means wildcard port match */
- if (scd->port > 0 && scd->port != ut->port)
+ if (scd->port > 0 && scd->port != port)
continue;
- if (strcmp(ut->host, scd->host))
+ if (strcmp(host, scd->host))
continue;
+ return sc;
+ }
+ return NULL;
+}
+
+static int udp_com_delete(struct sender_command_data *scd)
+{
+ struct udp_target *ut = sc->private_data;
+ struct sender_client *sc = udp_lookup_target(scd);
+
+ if (sc) {
udp_delete_target(ut, "com_delete");
+ return 1;
}
- return 1;
+ PARA_NOTICE_LOG("not deleting non-existing target '%s'\n", scd->host);
+ return -E_TARGET_NOT_FOUND;
}
/** Initialize UDP session and set maximum payload size. */
return mps;
}
+/** Check and clear socket error if any. */
+static int udp_check_socket_state(struct udp_target *ut)
+{
+ int ret;
+ socklen_t errlen = sizeof(ret);
+
+ if (getsockopt(ut->sc->fd, SOL_SOCKET, SO_ERROR, &ret, &errlen) < 0) {
+ PARA_ERROR_LOG("SO_ERROR failed: %s\n", strerror(ret));
+ return 0;
+ } else if (ret == 0) {
+ return 0;
+ } else if (ret == ECONNREFUSED) {
+ time_t dist = now->tv_sec - ut->last_unreachable;
+
+ if (dist <= UDP_MAX_UNREACHABLE_TIME) {
+ return 0;
+ } else if (dist > 2 * UDP_MAX_UNREACHABLE_TIME) {
+ ut->last_unreachable = now->tv_sec;
+ return 0;
+ } else {
+ /*
+ * unreachable_time < dist <= 2 * unreachable_time
+ * No errors are allowed during this time window.
+ */
+ PARA_NOTICE_LOG("Evicting %s after %d seconds "
+ "of connection errors.\n",
+ ut->sc->name, (int)dist);
+ }
+ }
+ return -ERRNO_TO_PARA_ERROR(ret);
+}
+
static int udp_send_fec(struct sender_client *sc, char *buf, size_t len)
{
struct udp_target *ut = sc->private_data;
if (sender_status == SENDER_OFF)
return 0;
+ if (len == 0 && !cq_peek(ut->sc->cq))
+ return 0;
+ ret = udp_check_socket_state(ut);
+ if (ret < 0)
+ goto fail;
ret = send_queued_chunks(sc->fd, sc->cq);
- if (ret == -ERRNO_TO_PARA_ERROR(ECONNREFUSED))
- ret = 0;
if (ret < 0)
goto fail;
- if (!len)
- return 0;
if (!ret) { /* still data left in the queue */
ret = cq_force_enqueue(sc->cq, buf, len);
assert(ret >= 0);
return 0;
}
ret = write_nonblock(sc->fd, buf, len);
- if (ret == -ERRNO_TO_PARA_ERROR(ECONNREFUSED))
+ if (ret == -ERRNO_TO_PARA_ERROR(ECONNREFUSED)) {
+ /*
+ * Happens if meanwhile an ICMP Destination / Port Unreachable
+ * has arrived. Ignore, persistent errors will be caught above.
+ */
ret = 0;
+ }
if (ret < 0)
goto fail;
if (ret != len) {
return ret;
}
-static void udp_add_target(struct sender_command_data *scd)
+static int udp_com_add(struct sender_command_data *scd)
{
- int ret, port = scd->port > 0 ? scd->port : conf.udp_default_port_arg;
- 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;
+ int ret;
+ struct udp_target *ut;
+ struct sender_client *sc = udp_lookup_target(scd);
+ if (sc) {
+ PARA_NOTICE_LOG("target %s already exists - not adding it\n",
+ sc->name);
+ return -E_TARGET_EXISTS;
+ }
+ ut = para_calloc(sizeof(*ut));
+ sc = ut->sc = para_calloc(sizeof(*sc));
ut->fcp.slices_per_group = scd->slices_per_group;
ut->fcp.data_slices_per_group = scd->data_slices_per_group;
ut->fcp.max_slice_bytes = scd->max_slice_bytes;
ut->fcp.init_fec = udp_init_fec;
ut->fcp.send_fec = udp_send_fec;
- ut->sc = para_calloc(sizeof(*ut->sc));
ut->sc->private_data = ut;
ut->sc->fd = -1;
- ret = para_connect_simple(IPPROTO_UDP, scd->host, port);
+ ret = para_connect_simple(IPPROTO_UDP, scd->host, scd->port);
if (ret < 0)
goto err;
ut->sc->fd = ret;
ret = mark_fd_nonblocking(ut->sc->fd);
if (ret < 0)
goto err;
- PARA_INFO_LOG("adding to target list (%s#%d)\n", ut->host, ut->port);
+ ut->sc->name = para_strdup(remote_name(ut->sc->fd));
+ PARA_INFO_LOG("adding to target list (%s)\n", ut->sc->name);
ut->fc = vss_add_fec_client(ut->sc, &ut->fcp);
para_list_add(&ut->sc->node, &targets);
- return;
+ return 1;
err:
if (ut->sc->fd >= 0)
close(ut->sc->fd);
- PARA_NOTICE_LOG("failed to set up %s#%d (%s)- not adding it\n",
- scd->host, port, para_strerror(-ret));
+ PARA_NOTICE_LOG("failed to set up %s:%d (%s)- not adding it\n",
+ scd->host, scd->port, para_strerror(-ret));
free(ut->sc);
free(ut);
-}
-
-static int udp_com_add(struct sender_command_data *scd)
-{
- udp_add_target(scd);
- return 1;
+ return ret;
}
static char *udp_info(void)
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,
- is_v6 ? "]" : "", ut->port,
+ char *tmp = make_message("%s%s/%u:%u:%u ", tgts ? : "",
+ ut->sc->name,
ut->fcp.max_slice_bytes,
ut->fcp.data_slices_per_group,
ut->fcp.slices_per_group
INIT_LIST_HEAD(&targets);
for (i = 0; i < conf.udp_target_given; i++) {
- if (parse_fec_url(conf.udp_target_arg[i], &scd) < 0) {
- PARA_CRIT_LOG("syntax error for udp target option "
- "#%d, ignoring\n", i);
- continue;
- }
- udp_add_target(&scd);
+ if (udp_resolve_target(conf.udp_target_arg[i], &scd) < 0)
+ PARA_CRIT_LOG("not adding requested target '%s'\n",
+ conf.udp_target_arg[i]);
+ else
+ udp_com_add(&scd);
}
}
s->pre_select = NULL;
s->post_select = NULL;
s->shutdown_clients = udp_shutdown_targets;
+ s->resolve_target = udp_resolve_target;
s->client_cmds[SENDER_ON] = udp_com_on;
s->client_cmds[SENDER_OFF] = udp_com_off;
s->client_cmds[SENDER_DENY] = NULL;