Implement new 'raw' input type for E1 timeslots
In the past, the A-bis E1 input system only unederstood LAPD signalling
time-slots and trau-slots with 16kBps sub-slots. This adds the notion
of a 'raw' transparent 64kBps slot, without any furthe de-multiplexing
nor any HLDC inside.
Change-Id: I0c25c2688eddd0c55c15b280a8c6e8a49629516b
diff --git a/src/input/misdn.c b/src/input/misdn.c
index 330e3b3..391cd18 100644
--- a/src/input/misdn.c
+++ b/src/input/misdn.c
@@ -391,6 +391,92 @@
return ret;
}
+/* write to a raw channel TS */
+static int handle_ts_raw_write(struct osmo_fd *bfd, unsigned int len)
+{
+ struct e1inp_line *line = bfd->data;
+ unsigned int ts_nr = bfd->priv_nr;
+ struct e1inp_ts *e1i_ts = &line->ts[ts_nr-1];
+ struct msgb *msg;
+ struct mISDNhead *hh;
+ int ret;
+
+ /* get the next msg for this timeslot */
+ msg = e1inp_tx_ts(e1i_ts, NULL);
+ if (!msg)
+ return 0;
+
+ if (msg->len != len) {
+ /* This might lead to a transmit underrun, as we call tx
+ * from the rx path, as there's no select/poll on dahdi
+ * */
+ LOGP(DLINP, LOGL_NOTICE, "unexpected msg->len = %u, "
+ "expected %u\n", msg->len, len);
+ }
+
+ DEBUGP(DLMIB, "RAW CHAN TX: %s\n",
+ osmo_hexdump(msg->data, msg->len));
+
+ hh = (struct mISDNhead *) msgb_push(msg, sizeof(*hh));
+ hh->prim = PH_DATA_REQ;
+ hh->id = 0;
+
+ ret = write(bfd->fd, msg->data, msg->len);
+ if (ret < msg->len)
+ LOGP(DLINP, LOGL_DEBUG, "send returns %d instead of %d\n",
+ ret, msg->len);
+ msgb_free(msg);
+
+ return ret;
+}
+
+static int handle_ts_raw_read(struct osmo_fd *bfd)
+{
+ struct e1inp_line *line = bfd->data;
+ unsigned int ts_nr = bfd->priv_nr;
+ struct e1inp_ts *e1i_ts = &line->ts[ts_nr-1];
+ struct msgb *msg = msgb_alloc(TSX_ALLOC_SIZE, "mISDN Tx RAW");
+ struct mISDNhead *hh;
+ int ret;
+
+ if (!msg)
+ return -ENOMEM;
+
+ hh = (struct mISDNhead *) msg->data;
+
+ ret = recv(bfd->fd, msg->data, TSX_ALLOC_SIZE, 0);
+ if (ret < 0) {
+ fprintf(stderr, "recvfrom error %s\n", strerror(errno));
+ return ret;
+ }
+
+ msgb_put(msg, ret);
+
+ if (hh->prim != PH_CONTROL_IND)
+ DEBUGP(DLMIB, "<= RAW CHAN len = %d, prim(0x%x) id(0x%x): %s\n",
+ ret, hh->prim, hh->id,
+ get_value_string(prim_names, hh->prim));
+
+ switch (hh->prim) {
+ case PH_DATA_IND:
+ msg->l2h = msg->data + MISDN_HEADER_LEN;
+ DEBUGP(DLMIB, "RAW CHAN RX: %s\n",
+ osmo_hexdump(msgb_l2(msg), ret - MISDN_HEADER_LEN));
+ /* the number of bytes received indicates that data to send */
+ handle_ts_raw_write(bfd, msgb_l2len(msg));
+ return e1inp_rx_ts(e1i_ts, msg, 0, 0);
+ case PH_ACTIVATE_IND:
+ case PH_DATA_CNF:
+ break;
+ default:
+ break;
+ }
+ /* FIXME: why do we free signalling msgs in the caller, and trau not? */
+ msgb_free(msg);
+
+ return ret;
+}
+
/* callback from select.c in case one of the fd's can be read/written */
static int misdn_fd_cb(struct osmo_fd *bfd, unsigned int what)
{
@@ -414,6 +500,13 @@
* writeset, since it doesn't support poll() based
* write flow control */
break;
+ case E1INP_TS_TYPE_RAW:
+ if (what & BSC_FD_READ)
+ rc = handle_ts_raw_read(bfd);
+ /* We never include the mISDN B-Channel FD into the
+ * writeset, since it doesn't support poll() based
+ * write flow control */
+ break;
default:
fprintf(stderr, "unknown E1 TS type %u\n", e1i_ts->type);
break;
@@ -524,6 +617,7 @@
bfd->when = BSC_FD_READ;
break;
case E1INP_TS_TYPE_TRAU:
+ case E1INP_TS_TYPE_RAW:
bfd->fd = socket(PF_ISDN, SOCK_DGRAM, ISDN_P_B_RAW);
/* We never include the mISDN B-Channel FD into the
* writeset, since it doesn't support poll() based