static int lldp_receive_datagram(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
_cleanup_(sd_lldp_neighbor_unrefp) sd_lldp_neighbor *n = NULL;
ssize_t space, length;
sd_lldp *lldp = userdata;
assert(fd >= 0);
assert(lldp);
space = next_datagram_size_fd(fd);
if (space < 0)
return log_lldp_errno(space, "Failed to determine datagram size to read: %m");
n = lldp_neighbor_new(space);
if (!n)
return -ENOMEM;
length = recv(fd, LLDP_NEIGHBOR_RAW(n), n->raw_size, MSG_DONTWAIT);
if (length < 0)
return log_lldp_errno(errno, "Failed to read LLDP datagram: %m");
if ((size_t) length != n->raw_size) {
log_lldp("Packet size mismatch.");
return -EINVAL;
}
return lldp_handle_datagram(lldp, n);
}
_public_ int sd_lldp_start(sd_lldp *lldp) {
int r;
assert_return(lldp, -EINVAL);
assert_return(lldp->event, -EINVAL);
assert_return(lldp->ifindex > 0, -EINVAL);
if (lldp->fd >= 0)
return 0;
assert(!lldp->io_event_source);
lldp->fd = lldp_network_bind_raw_socket(lldp->ifindex);
if (lldp->fd < 0)
return lldp->fd;
r = sd_event_add_io(lldp->event, &lldp->io_event_source, lldp->fd, EPOLLIN, lldp_receive_datagram, lldp);
if (r < 0)
goto fail;
r = sd_event_source_set_priority(lldp->io_event_source, lldp->event_priority);
if (r < 0)
goto fail;
(void) sd_event_source_set_description(lldp->io_event_source, "lldp-io");
log_lldp("Started LLDP client");
return 1;
fail:
lldp_reset(lldp);
return r;
}
static void lldp_callback(sd_lldp *lldp, sd_lldp_event event, sd_lldp_neighbor *n) {
assert(lldp);
log_lldp("Invoking callback for '%c'.", event);
if (!lldp->callback)
return;
lldp->callback(lldp, event, n, lldp->userdata);
}
_public_ int sd_lldp_stop(sd_lldp *lldp) {
assert_return(lldp, -EINVAL);
if (lldp->fd < 0)
return 0;
log_lldp("Stopping LLDP client");
lldp_reset(lldp);
lldp_flush_neighbors(lldp);
return 1;
}
static int lldp_handle_datagram(sd_lldp *lldp, sd_lldp_neighbor *n) {
int r;
assert(lldp);
assert(n);
r = lldp_neighbor_parse(n);
if (r == -EBADMSG) /* Ignore bad messages */
return 0;
if (r < 0)
return r;
r = lldp_add_neighbor(lldp, n);
if (r < 0) {
log_lldp_errno(r, "Failed to add datagram. Ignoring.");
return 0;
}
log_lldp("Successfully processed LLDP datagram.");
return 0;
}
static int lldp_receive_datagram(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
_cleanup_(sd_lldp_neighbor_unrefp) sd_lldp_neighbor *n = NULL;
ssize_t space, length;
sd_lldp *lldp = userdata;
struct timespec ts;
assert(fd >= 0);
assert(lldp);
space = next_datagram_size_fd(fd);
if (space < 0)
return log_lldp_errno(space, "Failed to determine datagram size to read: %m");
n = lldp_neighbor_new(space);
if (!n)
return -ENOMEM;
length = recv(fd, LLDP_NEIGHBOR_RAW(n), n->raw_size, MSG_DONTWAIT);
if (length < 0) {
if (errno == EAGAIN || errno == EINTR)
return 0;
return log_lldp_errno(errno, "Failed to read LLDP datagram: %m");
}
if ((size_t) length != n->raw_size) {
log_lldp("Packet size mismatch.");
return -EINVAL;
}
/* Try to get the timestamp of this packet if it is known */
if (ioctl(fd, SIOCGSTAMPNS, &ts) >= 0)
triple_timestamp_from_realtime(&n->timestamp, timespec_load(&ts));
else
triple_timestamp_get(&n->timestamp);
return lldp_handle_datagram(lldp, n);
}
