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authorHarald Welte <laforge@gnumonks.org>2009-06-10 05:40:52 +0800
committerHarald Welte <laforge@gnumonks.org>2009-06-10 05:40:52 +0800
commit13e10daa330ea2b699c9aa9d14b3adbd01111fd6 (patch)
treebf9144f9cf625baab472492b3047970cab14ef83 /openbsc/src/trau_mux.c
parentf7c43524cfc6e30a0223d3aaff89fe955d6e5146 (diff)
move openbsc into its own subdirectory
Diffstat (limited to 'openbsc/src/trau_mux.c')
-rw-r--r--openbsc/src/trau_mux.c212
1 files changed, 212 insertions, 0 deletions
diff --git a/openbsc/src/trau_mux.c b/openbsc/src/trau_mux.c
new file mode 100644
index 00000000..96f85899
--- /dev/null
+++ b/openbsc/src/trau_mux.c
@@ -0,0 +1,212 @@
+/* Simple TRAU frame reflector to route voice calls */
+
+/* (C) 2009 by Harald Welte <laforge@gnumonks.org>
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+
+#include <openbsc/gsm_data.h>
+#include <openbsc/trau_frame.h>
+#include <openbsc/trau_mux.h>
+#include <openbsc/subchan_demux.h>
+#include <openbsc/e1_input.h>
+#include <openbsc/debug.h>
+
+struct map_entry {
+ struct llist_head list;
+ struct gsm_e1_subslot src, dst;
+};
+
+struct upqueue_entry {
+ struct llist_head list;
+ struct gsm_network *net;
+ struct gsm_e1_subslot src;
+ u_int32_t callref;
+};
+
+static LLIST_HEAD(ss_map);
+static LLIST_HEAD(ss_upqueue);
+
+/* map one particular subslot to another subslot */
+int trau_mux_map(const struct gsm_e1_subslot *src,
+ const struct gsm_e1_subslot *dst)
+{
+ struct map_entry *me = malloc(sizeof(*me));
+ if (!me)
+ return -ENOMEM;
+
+ DEBUGP(DCC, "Setting up TRAU mux map between (e1=%u,ts=%u,ss=%u) "
+ "and (e1=%u,ts=%u,ss=%u)\n",
+ src->e1_nr, src->e1_ts, src->e1_ts_ss,
+ dst->e1_nr, dst->e1_ts, dst->e1_ts_ss);
+
+ /* make sure to get rid of any stale old mappings */
+ trau_mux_unmap(src, 0);
+ trau_mux_unmap(dst, 0);
+
+ memcpy(&me->src, src, sizeof(me->src));
+ memcpy(&me->dst, dst, sizeof(me->dst));
+ llist_add(&me->list, &ss_map);
+
+ return 0;
+}
+
+int trau_mux_map_lchan(const struct gsm_lchan *src,
+ const struct gsm_lchan *dst)
+{
+ struct gsm_e1_subslot *src_ss, *dst_ss;
+
+ src_ss = &src->ts->e1_link;
+ dst_ss = &dst->ts->e1_link;
+
+ return trau_mux_map(src_ss, dst_ss);
+}
+
+
+/* unmap one particular subslot from another subslot */
+int trau_mux_unmap(const struct gsm_e1_subslot *ss, u_int32_t callref)
+{
+ struct map_entry *me, *me2;
+ struct upqueue_entry *ue, *ue2;
+
+ if (ss)
+ llist_for_each_entry_safe(me, me2, &ss_map, list) {
+ if (!memcmp(&me->src, ss, sizeof(*ss)) ||
+ !memcmp(&me->dst, ss, sizeof(*ss))) {
+ llist_del(&me->list);
+ return 0;
+ }
+ }
+ llist_for_each_entry_safe(ue, ue2, &ss_upqueue, list) {
+ if (ue->callref == callref) {
+ llist_del(&ue->list);
+ return 0;
+ }
+ if (ss && !memcmp(&ue->src, ss, sizeof(*ss))) {
+ llist_del(&ue->list);
+ return 0;
+ }
+ }
+ return -ENOENT;
+}
+
+/* look-up an enty in the TRAU mux map */
+static struct gsm_e1_subslot *
+lookup_trau_mux_map(const struct gsm_e1_subslot *src)
+{
+ struct map_entry *me;
+
+ llist_for_each_entry(me, &ss_map, list) {
+ if (!memcmp(&me->src, src, sizeof(*src)))
+ return &me->dst;
+ if (!memcmp(&me->dst, src, sizeof(*src)))
+ return &me->src;
+ }
+ return NULL;
+}
+
+/* look-up an enty in the TRAU upqueue */
+struct upqueue_entry *
+lookup_trau_upqueue(const struct gsm_e1_subslot *src)
+{
+ struct upqueue_entry *ue;
+
+ llist_for_each_entry(ue, &ss_upqueue, list) {
+ if (!memcmp(&ue->src, src, sizeof(*src)))
+ return ue;
+ }
+ return NULL;
+}
+
+/* we get called by subchan_demux */
+int trau_mux_input(struct gsm_e1_subslot *src_e1_ss,
+ const u_int8_t *trau_bits, int num_bits)
+{
+ struct decoded_trau_frame tf;
+ u_int8_t trau_bits_out[TRAU_FRAME_BITS];
+ struct gsm_e1_subslot *dst_e1_ss = lookup_trau_mux_map(src_e1_ss);
+ struct subch_mux *mx;
+ int rc;
+
+ /* decode TRAU, change it to downlink, re-encode */
+ rc = decode_trau_frame(&tf, trau_bits);
+ if (rc)
+ return rc;
+
+ if (!dst_e1_ss)
+ return -EINVAL;
+
+ mx = e1inp_get_mux(dst_e1_ss->e1_nr, dst_e1_ss->e1_ts);
+ if (!mx)
+ return -EINVAL;
+
+ trau_frame_up2down(&tf);
+ encode_trau_frame(trau_bits_out, &tf);
+
+ /* and send it to the muxer */
+ return subchan_mux_enqueue(mx, dst_e1_ss->e1_ts_ss, trau_bits_out,
+ TRAU_FRAME_BITS);
+}
+
+/* add receiver instance for lchan and callref */
+int trau_recv_lchan(struct gsm_lchan *lchan, u_int32_t callref)
+{
+ struct gsm_e1_subslot *src_ss;
+ struct upqueue_entry *ue = malloc(sizeof(*ue));
+
+ if (!ue)
+ return -ENOMEM;
+
+ src_ss = &lchan->ts->e1_link;
+
+ DEBUGP(DCC, "Setting up TRAU receiver (e1=%u,ts=%u,ss=%u) "
+ "and (callref 0x%x)\n",
+ src_ss->e1_nr, src_ss->e1_ts, src_ss->e1_ts_ss,
+ callref);
+
+ /* make sure to get rid of any stale old mappings */
+ trau_mux_unmap(src_ss, callref);
+
+ memcpy(&ue->src, src_ss, sizeof(ue->src));
+ ue->net = lchan->ts->trx->bts->network;
+ ue->callref = callref;
+ llist_add(&ue->list, &ss_upqueue);
+
+ return 0;
+}
+
+int trau_send_lchan(struct gsm_lchan *lchan, struct decoded_trau_frame *tf)
+{
+ u_int8_t trau_bits_out[TRAU_FRAME_BITS];
+ struct gsm_e1_subslot *dst_e1_ss = &lchan->ts->e1_link;
+ struct subch_mux *mx;
+
+ mx = e1inp_get_mux(dst_e1_ss->e1_nr, dst_e1_ss->e1_ts);
+ if (!mx)
+ return -EINVAL;
+
+ encode_trau_frame(trau_bits_out, tf);
+
+ /* and send it to the muxer */
+ return subchan_mux_enqueue(mx, dst_e1_ss->e1_ts_ss, trau_bits_out,
+ TRAU_FRAME_BITS);
+}