mgcp: Deal with receiving another payload type
In case we get offered G729 and G711 we might have selected
G729 as the audio codec. The first packet we receive might be
G711 though. In that case we will need to change. But only if
we have a matching alternate codec payload_type. E.g. in the
case of comfort noise we will receive the PT=11 and we don't
want to change.
diff --git a/openbsc/tests/mgcp/mgcp_transcoding_test.c b/openbsc/tests/mgcp/mgcp_transcoding_test.c
index 079f62e..cf679b3 100644
--- a/openbsc/tests/mgcp/mgcp_transcoding_test.c
+++ b/openbsc/tests/mgcp/mgcp_transcoding_test.c
@@ -174,6 +174,9 @@
tcfg = talloc_zero(cfg, struct mgcp_trunk_config);
endp = talloc_zero(tcfg, struct mgcp_endpoint);
+ cfg->setup_rtp_processing_cb = mgcp_transcoding_setup;
+ cfg->rtp_processing_cb = mgcp_transcoding_process_rtp;
+ cfg->get_net_downlink_format_cb = mgcp_transcoding_net_downlink_format;
tcfg->endpoints = endp;
tcfg->number_endpoints = 1;
@@ -433,6 +436,63 @@
}
}
+static void test_transcode_change(void)
+{
+ char buf[4096] = {0x80, 0};
+ void *ctx;
+
+ struct mgcp_endpoint *endp;
+ struct mgcp_process_rtp_state *state;
+ struct rtp_hdr *hdr;
+
+ int len, res;
+
+ {
+ /* from GSM to PCMA and same ptime */
+ printf("Testing Initial G729->GSM, PCMA->GSM\n");
+ given_configured_endpoint(160, 0, "g729", "gsm", &ctx, &endp);
+ endp->net_end.alt_codec = endp->net_end.codec;
+ endp->net_end.alt_codec.payload_type = audio_name_to_type("pcma");
+ state = endp->bts_end.rtp_process_data;
+
+ /* initial transcoding work */
+ OSMO_ASSERT(state->src_fmt == AF_G729);
+ OSMO_ASSERT(state->dst_fmt == AF_GSM);
+ OSMO_ASSERT(endp->net_end.alt_codec.payload_type == 8);
+ OSMO_ASSERT(endp->net_end.codec.payload_type == 18);
+
+ /* result */
+ len = audio_packets_pcma[0].len;
+ memcpy(buf, audio_packets_pcma[0].data, len);
+ res = mgcp_transcoding_process_rtp(endp, &endp->bts_end, buf, &len, ARRAY_SIZE(buf));
+ OSMO_ASSERT(res == sizeof(struct rtp_hdr));
+ OSMO_ASSERT(state->sample_cnt == 0);
+ OSMO_ASSERT(state->src_fmt == AF_PCMA);
+ OSMO_ASSERT(state->dst_fmt == AF_GSM);
+ OSMO_ASSERT(endp->net_end.alt_codec.payload_type == 18);
+ OSMO_ASSERT(endp->net_end.codec.payload_type == 8);
+
+ len = res;
+ res = mgcp_transcoding_process_rtp(endp, &endp->bts_end, buf, &len, ARRAY_SIZE(buf));
+ OSMO_ASSERT(res == -ENOMSG);
+
+
+ /* now check that comfort noise doesn't change anything */
+ len = audio_packets_pcma[1].len;
+ memcpy(buf, audio_packets_pcma[1].data, len);
+ hdr = (struct rtp_hdr *) buf;
+ hdr->payload_type = 11;
+ res = mgcp_transcoding_process_rtp(endp, &endp->bts_end, buf, &len, ARRAY_SIZE(buf));
+ OSMO_ASSERT(state->sample_cnt == 80);
+ OSMO_ASSERT(state->src_fmt == AF_PCMA);
+ OSMO_ASSERT(state->dst_fmt == AF_GSM);
+ OSMO_ASSERT(endp->net_end.alt_codec.payload_type == 18);
+ OSMO_ASSERT(endp->net_end.codec.payload_type == 8);
+
+ talloc_free(ctx);
+ }
+}
+
static int test_repacking(int in_samples, int out_samples, int no_transcode)
{
char buf[4096] = {0x80, 0};
@@ -582,6 +642,7 @@
test_repacking(160, 100, 1);
test_rtp_seq_state();
test_transcode_result();
+ test_transcode_change();
return 0;
}