689 lines
20 KiB
C
689 lines
20 KiB
C
/* Minimalistic SDP parse/compose implementation, focused on GSM audio codecs */
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/*
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* (C) 2019 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
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* All Rights Reserved
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*
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* SPDX-License-Identifier: AGPL-3.0+
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*
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* Author: Neels Hofmeyr
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU Affero General Public License as published by
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* the Free Software Foundation; either version 3 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU Affero General Public License for more details.
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*
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* You should have received a copy of the GNU Affero General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#include <string.h>
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#include <errno.h>
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#include <osmocom/core/utils.h>
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#include <osmocom/core/logging.h>
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#include <osmocom/msc/debug.h>
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#include <osmocom/msc/sdp_msg.h>
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bool sdp_audio_codec_is_set(const struct sdp_audio_codec *a)
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{
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return a && a->subtype_name[0];
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}
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/* Compare name, rate and fmtp, returning typical cmp result: 0 on match, and -1 / 1 on mismatch.
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* If cmp_fmtp is false, do *not* compare the fmtp string; if true, compare fmtp 1:1 as strings.
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* If cmp_payload_type is false, do *not* compare the payload_type number.
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* The fmtp is only string-compared -- e.g. if AMR parameters appear in a different order, it amounts to a mismatch even
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* though all parameters are the same. */
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int sdp_audio_codec_cmp(const struct sdp_audio_codec *a, const struct sdp_audio_codec *b,
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bool cmp_fmtp, bool cmp_payload_type)
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{
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int cmp;
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if (a == b)
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return 0;
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if (!a)
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return -1;
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if (!b)
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return 1;
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cmp = strncmp(a->subtype_name, b->subtype_name, sizeof(a->subtype_name));
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if (cmp)
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return cmp;
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cmp = OSMO_CMP(a->rate, b->rate);
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if (cmp)
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return cmp;
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if (cmp_fmtp) {
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cmp = strncmp(a->fmtp, b->fmtp, sizeof(a->fmtp));
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if (cmp)
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return cmp;
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}
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if (cmp_payload_type) {
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cmp = OSMO_CMP(a->payload_type, b->payload_type);
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if (cmp)
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return cmp;
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}
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return 0;
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}
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/* Compare two lists of audio codecs, returning typical cmp result: 0 on match, and -1 / 1 on mismatch.
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* The ordering in the two lists may differ, except that the first codec in 'a' must also be the first codec in 'b'.
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* This is because the first codec typically expresses the preferred codec to use.
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* If cmp_fmtp is false, do *not* compare the fmtp strings; if true, compare fmtp 1:1 as strings.
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* If cmp_payload_type is false, do *not* compare the payload_type numbers.
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* The fmtp is only string-compared -- e.g. if AMR parameters appear in a different order, it amounts to a mismatch even
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* though all parameters are the same. */
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int sdp_audio_codecs_cmp(const struct sdp_audio_codecs *a, const struct sdp_audio_codecs *b,
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bool cmp_fmtp, bool cmp_payload_type)
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{
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const struct sdp_audio_codec *codec_a;
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const struct sdp_audio_codec *codec_b;
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int cmp;
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if (a == b)
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return 0;
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if (!a)
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return -1;
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if (!b)
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return 1;
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cmp = OSMO_CMP(a->count, b->count);
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if (cmp)
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return cmp;
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if (!a->count)
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return 0;
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/* The first codec is the "chosen" codec and should match. The others may appear in different order. */
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cmp = sdp_audio_codec_cmp(&a->codec[0], &b->codec[0], cmp_fmtp, cmp_payload_type);
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if (cmp)
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return cmp;
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/* See if each codec in a is also present in b */
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foreach_sdp_audio_codec(codec_a, a) {
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bool match_found = false;
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foreach_sdp_audio_codec(codec_b, b) {
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if (!sdp_audio_codec_cmp(codec_a, codec_b, cmp_fmtp, cmp_payload_type)) {
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match_found = true;
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break;
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}
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}
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if (!match_found)
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return -1;
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}
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return 0;
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}
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/* Given a predefined fixed payload_type number, add an SDP audio codec entry, if not present yet.
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* The payload_type must exist in sdp_msg_payload_type_names.
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* Return the audio codec created or already existing for this payload type number.
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*/
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struct sdp_audio_codec *sdp_audio_codecs_add(struct sdp_audio_codecs *ac, unsigned int payload_type,
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const char *subtype_name, unsigned int rate, const char *fmtp)
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{
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struct sdp_audio_codec *codec;
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/* Does an entry already exist? */
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codec = sdp_audio_codecs_by_payload_type(ac, payload_type, false);
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if (codec) {
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/* Already exists, sanity check */
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if (!codec->subtype_name[0])
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OSMO_STRLCPY_ARRAY(codec->subtype_name, subtype_name);
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else if (strcmp(codec->subtype_name, subtype_name)) {
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/* There already is an entry with this payload_type number but a mismatching subtype_name. That is
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* weird, rather abort. */
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return NULL;
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}
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if (codec->rate != rate
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|| (fmtp && strcmp(fmtp, codec->fmtp))) {
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/* Mismatching details. Rather abort */
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return NULL;
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}
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return codec;
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}
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/* None exists, create codec entry for this payload type number */
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codec = sdp_audio_codecs_by_payload_type(ac, payload_type, true);
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/* NULL means unable to add an entry */
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if (!codec)
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return NULL;
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OSMO_STRLCPY_ARRAY(codec->subtype_name, subtype_name);
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if (fmtp)
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OSMO_STRLCPY_ARRAY(codec->fmtp, fmtp);
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codec->rate = rate;
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return codec;
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}
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struct sdp_audio_codec *sdp_audio_codecs_add_copy(struct sdp_audio_codecs *ac, const struct sdp_audio_codec *codec)
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{
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return sdp_audio_codecs_add(ac, codec->payload_type, codec->subtype_name, codec->rate,
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codec->fmtp[0] ? codec->fmtp : NULL);
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}
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/* Find or create an entry for the given payload_type number in the given list of codecs.
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* If the given payload_type number is already present in ac, return the first matching entry.
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* If no such payload_type number is present: a) return NULL if create == false;
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* b) If create == true, add a mostly empty codec entry to the end of ac with the given payload_type number, and return
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* the created entry.
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* If create == true, a NULL return value means that there was no unused entry left in ac to add this payload_type.
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*/
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struct sdp_audio_codec *sdp_audio_codecs_by_payload_type(struct sdp_audio_codecs *ac, unsigned int payload_type,
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bool create)
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{
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struct sdp_audio_codec *codec;
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foreach_sdp_audio_codec(codec, ac) {
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if (codec->payload_type == payload_type)
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return codec;
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}
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if (!create)
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return NULL;
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/* Not found; codec points after the last entry now. */
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if ((codec - ac->codec) >= ARRAY_SIZE(ac->codec))
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return NULL;
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*codec = (struct sdp_audio_codec){
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.payload_type = payload_type,
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.rate = 8000,
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};
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ac->count = (codec - ac->codec) + 1;
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return codec;
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}
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/* Return a given sdp_msg's codec entry that matches the subtype_name and rate of the given codec, or NULL if no
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* match is found. Comparison is made by sdp_audio_codec_cmp(cmp_payload_type=false). */
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struct sdp_audio_codec *sdp_audio_codecs_by_descr(struct sdp_audio_codecs *ac, const struct sdp_audio_codec *codec)
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{
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struct sdp_audio_codec *i;
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foreach_sdp_audio_codec(i, ac) {
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if (!sdp_audio_codec_cmp(i, codec, false, false))
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return i;
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}
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return NULL;
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}
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/* Remove the codec entry pointed at by 'codec'. 'codec' must point at an entry of 'sdp' (to use an external codec
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* instance, use sdp_audio_codecs_by_descr()).
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* Return 0 on success, -ENOENT if codec does not point at the sdp->codec array. */
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int sdp_audio_codecs_remove(struct sdp_audio_codecs *ac, const struct sdp_audio_codec *codec)
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{
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struct sdp_audio_codec *i;
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if ((codec < ac->codec)
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|| ((codec - ac->codec) >= OSMO_MIN(ac->count, ARRAY_SIZE(ac->codec))))
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return -ENOENT;
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/* Move all following entries one up */
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ac->count--;
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foreach_sdp_audio_codec(i, ac) {
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if (i < codec)
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continue;
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*i = *(i+1);
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}
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return 0;
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}
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static const char * const sdp_mode_str[] = {
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[SDP_MODE_UNSET] = "-",
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[SDP_MODE_SENDONLY] = "sendonly",
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[SDP_MODE_RECVONLY] = "recvonly",
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[SDP_MODE_SENDRECV] = "sendrecv",
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[SDP_MODE_INACTIVE] = "inactive",
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};
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/* Convert struct sdp_msg to the actual SDP protocol representation */
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int sdp_msg_to_sdp_str_buf(char *dst, size_t dst_size, const struct sdp_msg *sdp)
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{
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const struct sdp_audio_codec *codec;
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struct osmo_strbuf sb = { .buf = dst, .len = dst_size };
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const char *ip;
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char ipv;
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if (!sdp) {
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OSMO_STRBUF_PRINTF(sb, "%s", "");
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return sb.chars_needed;
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}
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ip = sdp->rtp.ip[0] ? sdp->rtp.ip : "0.0.0.0";
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ipv = (osmo_ip_str_type(ip) == AF_INET6) ? '6' : '4';
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OSMO_STRBUF_PRINTF(sb,
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"v=0\r\n"
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"o=OsmoMSC 0 0 IN IP%c %s\r\n"
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"s=GSM Call\r\n"
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"c=IN IP%c %s\r\n"
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"t=0 0\r\n"
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"m=audio %d RTP/AVP",
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ipv, ip, ipv, ip,
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sdp->rtp.port);
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/* Append all payload type numbers to 'm=audio <port> RTP/AVP 3 4 112' line */
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foreach_sdp_audio_codec(codec, &sdp->audio_codecs)
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OSMO_STRBUF_PRINTF(sb, " %d", codec->payload_type);
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OSMO_STRBUF_PRINTF(sb, "\r\n");
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/* Add details for all codecs */
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foreach_sdp_audio_codec(codec, &sdp->audio_codecs) {
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if (!sdp_audio_codec_is_set(codec))
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continue;
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OSMO_STRBUF_PRINTF(sb, "a=rtpmap:%d %s/%d\r\n", codec->payload_type, codec->subtype_name,
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codec->rate > 0 ? codec->rate : 8000);
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if (codec->fmtp[0])
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OSMO_STRBUF_PRINTF(sb, "a=fmtp:%d %s\r\n", codec->payload_type, codec->fmtp);
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}
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OSMO_STRBUF_PRINTF(sb, "a=ptime:%d\r\n", sdp->ptime > 0? sdp->ptime : 20);
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if (sdp->mode != SDP_MODE_UNSET && sdp->mode < ARRAY_SIZE(sdp_mode_str))
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OSMO_STRBUF_PRINTF(sb, "a=%s\r\n", sdp_mode_str[sdp->mode]);
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return sb.chars_needed;
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}
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/* Return the first line ending (or the end of the string) at or after the given string position. */
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const char *sdp_msg_line_end(const char *src)
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{
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const char *line_end = strchr(src, '\r');
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if (!line_end)
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line_end = strchr(src, '\n');
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if (!line_end)
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line_end = src + strlen(src);
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return line_end;
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}
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/* parse a line like 'a=rtpmap:0 PCMU/8000', 'a=fmtp:112 octet-align=1; mode-set=4', 'a=ptime:20'.
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* The src should point at the character after 'a=', e.g. at the start of 'rtpmap', 'fmtp', 'ptime'
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*/
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int sdp_parse_attrib(struct sdp_msg *sdp, const char *src)
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{
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unsigned int payload_type;
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struct sdp_audio_codec *codec;
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#define A_RTPMAP "rtpmap:"
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#define A_FMTP "fmtp:"
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#define A_PTIME "ptime:"
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#define A_RTCP "rtcp:"
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if (osmo_str_startswith(src, A_RTPMAP)) {
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/* "a=rtpmap:3 GSM/8000" */
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char *audio_name;
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unsigned int channels = 1;
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if (sscanf(src, A_RTPMAP "%u", &payload_type) != 1)
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return -EINVAL;
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audio_name = strchr(src, ' ');
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if (!audio_name || audio_name >= sdp_msg_line_end(src))
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return -EINVAL;
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codec = sdp_audio_codecs_by_payload_type(&sdp->audio_codecs, payload_type, true);
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if (!codec)
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return -ENOSPC;
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if (sscanf(audio_name, " %31[^/]/%u/%u", codec->subtype_name, &codec->rate, &channels) < 1)
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return -EINVAL;
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if (channels != 1)
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return -ENOTSUP;
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}
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else if (osmo_str_startswith(src, A_FMTP)) {
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/* "a=fmtp:112 octet-align=1;mode-set=0,1,2,3" */
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char *fmtp_str;
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const char *line_end = sdp_msg_line_end(src);
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if (sscanf(src, A_FMTP "%u", &payload_type) != 1)
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return -EINVAL;
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fmtp_str = strchr(src, ' ');
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if (!fmtp_str)
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return -EINVAL;
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fmtp_str++;
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if (fmtp_str >= line_end)
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return -EINVAL;
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codec = sdp_audio_codecs_by_payload_type(&sdp->audio_codecs, payload_type, true);
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if (!codec)
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return -ENOSPC;
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/* (+1 because osmo_strlcpy() interprets it as size including the '\0') */
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osmo_strlcpy(codec->fmtp, fmtp_str, line_end - fmtp_str + 1);
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}
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else if (osmo_str_startswith(src, A_PTIME)) {
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/* "a=ptime:20" */
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if (sscanf(src, A_PTIME "%u", &sdp->ptime) != 1)
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return -EINVAL;
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}
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else if (osmo_str_startswith(src, A_RTCP)) {
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/* TODO? */
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}
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else if (osmo_str_startswith(src, sdp_mode_str[SDP_MODE_SENDRECV])) {
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/* "a=sendrecv" */
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sdp->mode = SDP_MODE_SENDRECV;
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}
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else if (osmo_str_startswith(src, sdp_mode_str[SDP_MODE_SENDONLY])) {
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/* "a=sendonly" */
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sdp->mode = SDP_MODE_SENDONLY;
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}
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else if (osmo_str_startswith(src, sdp_mode_str[SDP_MODE_RECVONLY])) {
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/* "a=recvonly" */
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sdp->mode = SDP_MODE_RECVONLY;
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}
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else if (osmo_str_startswith(src, sdp_mode_str[SDP_MODE_INACTIVE])) {
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/* "a=inactive" */
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sdp->mode = SDP_MODE_INACTIVE;
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}
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return 0;
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}
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const struct value_string sdp_msg_payload_type_names[] = {
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{ 0, "PCMU" },
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{ 3, "GSM" },
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{ 8, "PCMA" },
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{ 18, "G729" },
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{ 110, "GSM-EFR" },
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{ 111, "GSM-HR-08" },
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{ 112, "AMR" },
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{ 113, "AMR-WB" },
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{}
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};
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/* Return payload type number matching given string ("AMR", "GSM", ...) or negative if not found. */
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int sdp_subtype_name_to_payload_type(const char *subtype_name)
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{
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return get_string_value(sdp_msg_payload_type_names, subtype_name);
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}
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/* Parse a line like 'm=audio 16398 RTP/AVP 0 3 8 96 112', starting after the '=' */
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static int sdp_parse_media_description(struct sdp_msg *sdp, const char *src)
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{
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unsigned int port;
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int i;
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const char *payload_type_str;
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const char *line_end = sdp_msg_line_end(src);
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if (sscanf(src, "audio %u RTP/AVP", &port) < 1)
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return -ENOTSUP;
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if (port > 0xffff)
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return -EINVAL;
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sdp->rtp.port = port;
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/* skip "audio 12345 RTP/AVP ", i.e. 3 spaces on */
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payload_type_str = src;
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for (i = 0; i < 3; i++) {
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payload_type_str = strchr(payload_type_str, ' ');
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if (!payload_type_str)
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return -EINVAL;
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while (*payload_type_str == ' ')
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payload_type_str++;
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if (payload_type_str >= line_end)
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return -EINVAL;
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}
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/* Parse listing of payload type numbers after "RTP/AVP" */
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while (payload_type_str < line_end) {
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unsigned int payload_type;
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struct sdp_audio_codec *codec;
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const char *subtype_name;
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if (sscanf(payload_type_str, "%u", &payload_type) < 1)
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return -EINVAL;
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codec = sdp_audio_codecs_by_payload_type(&sdp->audio_codecs, payload_type, true);
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if (!codec)
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return -ENOSPC;
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/* Fill in subtype name for fixed payload types */
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subtype_name = get_value_string_or_null(sdp_msg_payload_type_names, codec->payload_type);
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if (subtype_name)
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OSMO_STRLCPY_ARRAY(codec->subtype_name, subtype_name);
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payload_type_str = strchr(payload_type_str, ' ');
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if (!payload_type_str)
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payload_type_str = line_end;
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while (*payload_type_str == ' ')
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payload_type_str++;
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|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* parse a line like 'c=IN IP4 192.168.11.151' starting after the '=' */
|
|
static int sdp_parse_connection_info(struct sdp_msg *sdp, const char *src)
|
|
{
|
|
char ipv[10];
|
|
char addr_str[INET6_ADDRSTRLEN];
|
|
if (sscanf(src, "IN %s %s", ipv, addr_str) < 2)
|
|
return -EINVAL;
|
|
|
|
/* supporting only IPv4 */
|
|
if (strcmp(ipv, "IP4"))
|
|
return -ENOTSUP;
|
|
|
|
osmo_sockaddr_str_from_str(&sdp->rtp, addr_str, sdp->rtp.port);
|
|
return 0;
|
|
}
|
|
|
|
/* Parse SDP string into struct sdp_msg. Return 0 on success, negative on error. */
|
|
int sdp_msg_from_sdp_str(struct sdp_msg *sdp, const char *src)
|
|
{
|
|
const char *pos;
|
|
*sdp = (struct sdp_msg){};
|
|
|
|
for (pos = src; pos && *pos; pos++) {
|
|
char attrib;
|
|
int rc = 0;
|
|
|
|
if (*pos == '\r' || *pos == '\n')
|
|
continue;
|
|
|
|
/* Expecting only lines starting with 'X='. Not being too strict about it is probably alright. */
|
|
if (pos[1] != '=')
|
|
goto next_line;
|
|
|
|
attrib = *pos;
|
|
pos += 2;
|
|
switch (attrib) {
|
|
/* a=... */
|
|
case 'a':
|
|
rc = sdp_parse_attrib(sdp, pos);
|
|
break;
|
|
case 'm':
|
|
rc = sdp_parse_media_description(sdp, pos);
|
|
break;
|
|
case 'c':
|
|
rc = sdp_parse_connection_info(sdp, pos);
|
|
break;
|
|
default:
|
|
/* ignore any other parameters */
|
|
break;
|
|
}
|
|
|
|
if (rc) {
|
|
size_t line_len;
|
|
const char *line_end = sdp_msg_line_end(pos);
|
|
pos -= 2;
|
|
line_len = line_end - pos;
|
|
switch (rc) {
|
|
case -EINVAL:
|
|
LOGP(DMNCC, LOGL_ERROR,
|
|
"Failed to parse SDP: invalid line: %s\n", osmo_quote_str(pos, line_len));
|
|
break;
|
|
case -ENOSPC:
|
|
LOGP(DMNCC, LOGL_ERROR,
|
|
"Failed to parse SDP: no more space for: %s\n", osmo_quote_str(pos, line_len));
|
|
break;
|
|
case -ENOTSUP:
|
|
LOGP(DMNCC, LOGL_ERROR,
|
|
"Failed to parse SDP: not supported: %s\n", osmo_quote_str(pos, line_len));
|
|
break;
|
|
default:
|
|
LOGP(DMNCC, LOGL_ERROR,
|
|
"Failed to parse SDP: %s\n", osmo_quote_str(pos, line_len));
|
|
break;
|
|
}
|
|
return rc;
|
|
}
|
|
next_line:
|
|
pos = strstr(pos, "\r\n");
|
|
if (!pos)
|
|
break;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Leave only those codecs in 'ac_dest' that are also present in 'ac_other'.
|
|
* The matching is made by sdp_audio_codec_cmp(cmp_payload_type=false), i.e. payload_type numbers are not compared and
|
|
* fmtp parameters are compared 1:1 as plain strings.
|
|
* If translate_payload_type_numbers has an effect if ac_dest and ac_other have mismatching payload_type numbers for the
|
|
* same SDP codec descriptions. If translate_payload_type_numbers is true, take the payload_type numbers from ac_other.
|
|
* If false, keep payload_type numbers in ac_dest unchanged. */
|
|
void sdp_audio_codecs_intersection(struct sdp_audio_codecs *ac_dest, const struct sdp_audio_codecs *ac_other,
|
|
bool translate_payload_type_numbers)
|
|
{
|
|
int i;
|
|
for (i = 0; i < ac_dest->count; i++) {
|
|
struct sdp_audio_codec *codec = &ac_dest->codec[i];
|
|
struct sdp_audio_codec *other;
|
|
OSMO_ASSERT(i < ARRAY_SIZE(ac_dest->codec));
|
|
|
|
other = sdp_audio_codecs_by_descr((struct sdp_audio_codecs *)ac_other, codec);
|
|
|
|
if (!other) {
|
|
OSMO_ASSERT(sdp_audio_codecs_remove(ac_dest, codec) == 0);
|
|
i--;
|
|
continue;
|
|
}
|
|
|
|
/* Doing payload_type number translation of part of the intersection because it makes the algorithm
|
|
* simpler: we already know ac_dest is a subset of ac_other, and there is no need to resolve payload
|
|
* type number conflicts. */
|
|
if (translate_payload_type_numbers)
|
|
codec->payload_type = other->payload_type;
|
|
}
|
|
}
|
|
|
|
/* Make sure the given codec is listed as the first codec. 'codec' must be an actual codec entry of the given audio
|
|
* codecs list. */
|
|
void sdp_audio_codecs_select(struct sdp_audio_codecs *ac, struct sdp_audio_codec *codec)
|
|
{
|
|
struct sdp_audio_codec tmp;
|
|
struct sdp_audio_codec *pos;
|
|
OSMO_ASSERT((codec >= ac->codec)
|
|
&& ((codec - ac->codec) < OSMO_MIN(ac->count, ARRAY_SIZE(ac->codec))));
|
|
|
|
/* Already the first? */
|
|
if (codec == ac->codec)
|
|
return;
|
|
|
|
tmp = *codec;
|
|
for (pos = codec - 1; pos >= ac->codec; pos--)
|
|
pos[1] = pos[0];
|
|
|
|
ac->codec[0] = tmp;
|
|
return;
|
|
}
|
|
|
|
/* Short single-line representation of an SDP audio codec, convenient for logging.
|
|
* Like "AMR/8000:octet-align=1#122" */
|
|
int sdp_audio_codec_to_str_buf(char *buf, size_t buflen, const struct sdp_audio_codec *codec)
|
|
{
|
|
struct osmo_strbuf sb = { .buf = buf, .len = buflen };
|
|
OSMO_STRBUF_PRINTF(sb, "%s", codec->subtype_name);
|
|
if (codec->rate != 8000)
|
|
OSMO_STRBUF_PRINTF(sb, "/%u", codec->rate);
|
|
if (codec->fmtp[0])
|
|
OSMO_STRBUF_PRINTF(sb, ":%s", codec->fmtp);
|
|
OSMO_STRBUF_PRINTF(sb, "#%d", codec->payload_type);
|
|
return sb.chars_needed;
|
|
}
|
|
|
|
char *sdp_audio_codec_to_str_c(void *ctx, const struct sdp_audio_codec *codec)
|
|
{
|
|
OSMO_NAME_C_IMPL(ctx, 32, "sdp_audio_codec_to_str_c-ERROR", sdp_audio_codec_to_str_buf, codec)
|
|
}
|
|
|
|
const char *sdp_audio_codec_to_str(const struct sdp_audio_codec *codec)
|
|
{
|
|
return sdp_audio_codec_to_str_c(OTC_SELECT, codec);
|
|
}
|
|
|
|
/* Short single-line representation of a list of SDP audio codecs, convenient for logging */
|
|
int sdp_audio_codecs_to_str_buf(char *buf, size_t buflen, const struct sdp_audio_codecs *ac)
|
|
{
|
|
struct osmo_strbuf sb = { .buf = buf, .len = buflen };
|
|
const struct sdp_audio_codec *codec;
|
|
if (!ac->count)
|
|
OSMO_STRBUF_PRINTF(sb, "(no-codecs)");
|
|
foreach_sdp_audio_codec(codec, ac) {
|
|
bool first = (codec == ac->codec);
|
|
if (!first)
|
|
OSMO_STRBUF_PRINTF(sb, ",");
|
|
OSMO_STRBUF_APPEND(sb, sdp_audio_codec_to_str_buf, codec);
|
|
}
|
|
return sb.chars_needed;
|
|
}
|
|
|
|
char *sdp_audio_codecs_to_str_c(void *ctx, const struct sdp_audio_codecs *ac)
|
|
{
|
|
OSMO_NAME_C_IMPL(ctx, 128, "sdp_audio_codecs_to_str_c-ERROR", sdp_audio_codecs_to_str_buf, ac)
|
|
}
|
|
|
|
const char *sdp_audio_codecs_to_str(const struct sdp_audio_codecs *ac)
|
|
{
|
|
return sdp_audio_codecs_to_str_c(OTC_SELECT, ac);
|
|
}
|
|
|
|
/* Short single-line representation of an SDP message, convenient for logging */
|
|
int sdp_msg_to_str_buf(char *buf, size_t buflen, const struct sdp_msg *sdp)
|
|
{
|
|
struct osmo_strbuf sb = { .buf = buf, .len = buflen };
|
|
if (!sdp) {
|
|
OSMO_STRBUF_PRINTF(sb, "NULL");
|
|
return sb.chars_needed;
|
|
}
|
|
|
|
OSMO_STRBUF_PRINTF(sb, OSMO_SOCKADDR_STR_FMT, OSMO_SOCKADDR_STR_FMT_ARGS(&sdp->rtp));
|
|
OSMO_STRBUF_PRINTF(sb, "{");
|
|
OSMO_STRBUF_APPEND(sb, sdp_audio_codecs_to_str_buf, &sdp->audio_codecs);
|
|
if (sdp->bearer_services.count) {
|
|
OSMO_STRBUF_PRINTF(sb, ",");
|
|
OSMO_STRBUF_APPEND(sb, csd_bs_list_to_str_buf, &sdp->bearer_services);
|
|
}
|
|
OSMO_STRBUF_PRINTF(sb, "}");
|
|
return sb.chars_needed;
|
|
}
|
|
|
|
char *sdp_msg_to_str_c(void *ctx, const struct sdp_msg *sdp)
|
|
{
|
|
OSMO_NAME_C_IMPL(ctx, 128, "sdp_msg_to_str_c-ERROR", sdp_msg_to_str_buf, sdp)
|
|
}
|
|
|
|
const char *sdp_msg_to_str(const struct sdp_msg *sdp)
|
|
{
|
|
return sdp_msg_to_str_c(OTC_SELECT, sdp);
|
|
}
|
|
|
|
void sdp_audio_codecs_set_csd(struct sdp_audio_codecs *ac)
|
|
{
|
|
*ac = (struct sdp_audio_codecs){
|
|
.count = 1,
|
|
.codec = {{
|
|
.payload_type = 120,
|
|
.subtype_name = "CLEARMODE",
|
|
.rate = 8000,
|
|
}},
|
|
};
|
|
}
|