mirror of
https://gitea.osmocom.org/cellular-infrastructure/osmo-mgw.git
synced 2025-10-23 08:12:01 +00:00
dc7dfd0bbd
The new mode "confecho" is similar to "sendrecv", except that it also echoes back RTP towards the sender. This is required for voice group or broadcast calls. Talker and listeners use the same timeslot, so that audio must be echoed from the talker to the listeners. It is different from "loopback", because a loopback only echoes back RTP towards the sender, but does not forward audio through the endpoint to the other connections. Also it does not forward RTP from senders of other connections. The current implementation of MGW does not support transcoding and mixing. This means that a sending connection must not send RTP that has been received by multiple receiving connections. The application that uses the MGW has to set the connection modes, so that only one connection receives RTP in case of a conference. Change-Id: I0639c663e119d85bef1010c7aa45e2f133a9daf0 Related: OS#4853
113 lines
3.6 KiB
C
113 lines
3.6 KiB
C
/* MGCP common implementations.
|
|
* These are used in libosmo-mgcp as well as libosmo-mgcp-client.
|
|
* To avoid interdependency, these are implemented in .h file only. */
|
|
|
|
/*
|
|
* (C) 2017 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
|
|
* (C) 2009-2012 by Holger Hans Peter Freyther <zecke@selfish.org>
|
|
* (C) 2009-2012 by On-Waves
|
|
* All Rights Reserved
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU Affero General Public License as published by
|
|
* the Free Software Foundation; either version 3 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 Affero General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Affero General Public License
|
|
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
*
|
|
*/
|
|
|
|
/* Two copies of this file are kept in osmocom/mgcp/ and osmocom/mgcp_client/.
|
|
* Since both are by definition identical, use the old header exclusion ifdefs
|
|
* instead of '#pragma once' to avoid including both of these files.
|
|
* Though at the time of writing there are no such users, this allows including
|
|
* both libosmo-mgcp and libosmo-mgcp-client headers in the same file. */
|
|
#ifndef OSMO_MGCP_COMMON_H
|
|
#define OSMO_MGCP_COMMON_H
|
|
|
|
#include <string.h>
|
|
#include <errno.h>
|
|
|
|
#include <osmocom/core/msgb.h>
|
|
#include <osmocom/core/logging.h>
|
|
|
|
#define for_each_non_empty_line(line, save) \
|
|
for (line = strtok_r(NULL, "\r\n", &save); line; \
|
|
line = strtok_r(NULL, "\r\n", &save))
|
|
|
|
enum mgcp_connection_mode {
|
|
MGCP_CONN_NONE = 0,
|
|
MGCP_CONN_RECV_ONLY = 1,
|
|
MGCP_CONN_SEND_ONLY = 2,
|
|
MGCP_CONN_RECV_SEND = MGCP_CONN_RECV_ONLY | MGCP_CONN_SEND_ONLY,
|
|
MGCP_CONN_LOOPBACK = 4 | MGCP_CONN_RECV_SEND,
|
|
MGCP_CONN_CONFECHO = 8 | MGCP_CONN_RECV_SEND,
|
|
};
|
|
|
|
#define MGCP_X_OSMO_IGN_HEADER "X-Osmo-IGN:"
|
|
#define MGCP_X_OSMO_OSMUX_HEADER "X-Osmux:"
|
|
|
|
/* Values should be bitwise-OR-able */
|
|
enum mgcp_x_osmo_ign {
|
|
MGCP_X_OSMO_IGN_NONE = 0,
|
|
MGCP_X_OSMO_IGN_CALLID = 1,
|
|
};
|
|
|
|
/* Codec parameters (communicated via SDP/fmtp) */
|
|
struct mgcp_codec_param {
|
|
bool amr_octet_aligned_present;
|
|
bool amr_octet_aligned;
|
|
};
|
|
|
|
/* Ensure that the msg->l2h is NUL terminated. */
|
|
static inline int mgcp_msg_terminate_nul(struct msgb *msg)
|
|
{
|
|
unsigned char *tail = msg->l2h + msgb_l2len(msg); /* char after l2 data */
|
|
if (tail[-1] == '\0')
|
|
/* nothing to do */;
|
|
else if (msgb_tailroom(msg) > 0)
|
|
tail[0] = '\0';
|
|
else if (tail[-1] == '\r' || tail[-1] == '\n')
|
|
tail[-1] = '\0';
|
|
else {
|
|
LOGP(DLMGCP, LOGL_ERROR, "Cannot NUL terminate MGCP message: "
|
|
"Length: %d, Buffer size: %d\n",
|
|
msgb_l2len(msg), msg->data_len);
|
|
return -ENOTSUP;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/* Maximum length of the comment field */
|
|
#define MGCP_COMMENT_MAXLEN 256
|
|
|
|
/* Maximum allowed String length of Connection Identifiers as per spec
|
|
* (see also RFC3435 2.1.3.2 Names of Connections), plus one for '\0'. */
|
|
#define MGCP_CONN_ID_MAXLEN 32+1
|
|
|
|
/* Deprecated: old name of MGCP_CONN_ID_MAXLEN. */
|
|
#define MGCP_CONN_ID_LENGTH MGCP_CONN_ID_MAXLEN
|
|
|
|
/* String length of Endpoint Identifiers.
|
|
/ (see also RFC3435 section 3.2.1.3) */
|
|
#define MGCP_ENDPOINT_MAXLEN (255*2+1+1)
|
|
|
|
/* A prefix to denote the virtual trunk (RTP on both ends) */
|
|
#define MGCP_ENDPOINT_PREFIX_VIRTUAL_TRUNK "rtpbridge/"
|
|
|
|
/* A prefix to denote the e1 trunk
|
|
* (see also RFC3435 section E.2) */
|
|
#define MGCP_ENDPOINT_PREFIX_E1_TRUNK "ds/e1-"
|
|
|
|
/* Maximal number of payload types / codecs that can be negotiated via SDP at
|
|
* at once. */
|
|
#define MGCP_MAX_CODECS 10
|
|
|
|
#endif
|