ZLMediaKit/webrtc/Sdp.cpp
zx cd4e772985
remove dumplicate line rtc_media.type
remove  dumplicate line 

`rtc_media.type = mline.type;`
2022-03-04 16:18:26 +08:00

1797 lines
60 KiB
C++
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/*
* Copyright (c) 2016 The ZLMediaKit project authors. All Rights Reserved.
*
* This file is part of ZLMediaKit(https://github.com/xia-chu/ZLMediaKit).
*
* Use of this source code is governed by MIT license that can be found in the
* LICENSE file in the root of the source tree. All contributing project authors
* may be found in the AUTHORS file in the root of the source tree.
*/
#include "Sdp.h"
#include "Rtsp/Rtsp.h"
#include <cinttypes>
using namespace std;
using namespace toolkit;
using namespace mediakit;
namespace RTC {
#define RTC_FIELD "rtc."
const string kPreferredCodecA = RTC_FIELD"preferredCodecA";
const string kPreferredCodecV = RTC_FIELD"preferredCodecV";
static onceToken token([]() {
mINI::Instance()[kPreferredCodecA] = "PCMU,PCMA,opus,mpeg4-generic";
mINI::Instance()[kPreferredCodecV] = "H264,H265,AV1X,VP9,VP8";
});
}
using onCreateSdpItem = function<SdpItem::Ptr(const string &key, const string &value)>;
static map<string, onCreateSdpItem, StrCaseCompare> sdpItemCreator;
template <typename Item>
void registerSdpItem(){
onCreateSdpItem func = [](const string &key, const string &value) {
auto ret = std::make_shared<Item>();
ret->parse(value);
return ret;
};
Item item;
sdpItemCreator.emplace(item.getKey(), std::move(func));
}
class DirectionInterface {
public:
virtual RtpDirection getDirection() const = 0;
};
class SdpDirectionSendonly : public SdpItem, public DirectionInterface{
public:
const char* getKey() const override { return getRtpDirectionString(getDirection());}
RtpDirection getDirection() const override {return RtpDirection::sendonly;}
};
class SdpDirectionRecvonly : public SdpItem, public DirectionInterface{
public:
const char* getKey() const override { return getRtpDirectionString(getDirection());}
RtpDirection getDirection() const override {return RtpDirection::recvonly;}
};
class SdpDirectionSendrecv : public SdpItem, public DirectionInterface{
public:
const char* getKey() const override { return getRtpDirectionString(getDirection());}
RtpDirection getDirection() const override {return RtpDirection::sendrecv;}
};
class SdpDirectionInactive : public SdpItem, public DirectionInterface{
public:
const char* getKey() const override { return getRtpDirectionString(getDirection());}
RtpDirection getDirection() const override {return RtpDirection::inactive;}
};
class DirectionInterfaceImp : public SdpItem, public DirectionInterface{
public:
DirectionInterfaceImp(RtpDirection direct){
direction = direct;
}
const char* getKey() const override { return getRtpDirectionString(getDirection());}
RtpDirection getDirection() const override {return direction;}
private:
RtpDirection direction;
};
static bool registerAllItem(){
registerSdpItem<SdpString<'v'> >();
registerSdpItem<SdpString<'s'> >();
registerSdpItem<SdpString<'i'> >();
registerSdpItem<SdpString<'u'> >();
registerSdpItem<SdpString<'e'> >();
registerSdpItem<SdpString<'p'> >();
registerSdpItem<SdpString<'z'> >();
registerSdpItem<SdpString<'k'> >();
registerSdpItem<SdpString<'r'> >();
registerSdpItem<SdpTime>();
registerSdpItem<SdpOrigin>();
registerSdpItem<SdpConnection>();
registerSdpItem<SdpBandwidth>();
registerSdpItem<SdpMedia>();
registerSdpItem<SdpAttr>();
registerSdpItem<SdpAttrGroup>();
registerSdpItem<SdpAttrMsidSemantic>();
registerSdpItem<SdpAttrRtcp>();
registerSdpItem<SdpAttrIceUfrag>();
registerSdpItem<SdpAttrIcePwd>();
registerSdpItem<SdpAttrIceOption>();
registerSdpItem<SdpAttrFingerprint>();
registerSdpItem<SdpAttrSetup>();
registerSdpItem<SdpAttrMid>();
registerSdpItem<SdpAttrExtmap>();
registerSdpItem<SdpAttrRtpMap>();
registerSdpItem<SdpAttrRtcpFb>();
registerSdpItem<SdpAttrFmtp>();
registerSdpItem<SdpAttrSSRC>();
registerSdpItem<SdpAttrSSRCGroup>();
registerSdpItem<SdpAttrSctpMap>();
registerSdpItem<SdpAttrCandidate>();
registerSdpItem<SdpDirectionSendonly>();
registerSdpItem<SdpDirectionRecvonly>();
registerSdpItem<SdpDirectionSendrecv>();
registerSdpItem<SdpDirectionInactive>();
registerSdpItem<SdpAttrMsid>();
registerSdpItem<SdpAttrExtmapAllowMixed>();
registerSdpItem<SdpAttrRid>();
registerSdpItem<SdpAttrSimulcast>();
return true;
}
static map<string, DtlsRole, StrCaseCompare> dtls_role_map = {
{"active", DtlsRole::active},
{"passive", DtlsRole::passive},
{"actpass", DtlsRole::actpass}
};
DtlsRole getDtlsRole(const string &str) {
auto it = dtls_role_map.find(str);
return it == dtls_role_map.end() ? DtlsRole::invalid : it->second;
}
const char* getDtlsRoleString(DtlsRole role){
switch (role) {
case DtlsRole::active : return "active";
case DtlsRole::passive : return "passive";
case DtlsRole::actpass : return "actpass";
default: return "invalid";
}
}
static map<string, RtpDirection, StrCaseCompare> direction_map = {
{"sendonly", RtpDirection::sendonly},
{"recvonly", RtpDirection::recvonly},
{"sendrecv", RtpDirection::sendrecv},
{"inactive", RtpDirection::inactive}
};
RtpDirection getRtpDirection(const string &str) {
auto it = direction_map.find(str);
return it == direction_map.end() ? RtpDirection::invalid : it->second;
}
const char* getRtpDirectionString(RtpDirection val){
switch (val) {
case RtpDirection::sendonly : return "sendonly";
case RtpDirection::recvonly : return "recvonly";
case RtpDirection::sendrecv : return "sendrecv";
case RtpDirection::inactive : return "inactive";
default: return "invalid";
}
}
//////////////////////////////////////////////////////////////////////////////////////////
string RtcSdpBase::toString() const {
_StrPrinter printer;
for (auto &item : items) {
printer << item->getKey() << "=" << item->toString() << "\r\n";
}
return std::move(printer);
}
RtpDirection RtcSdpBase::getDirection() const{
for (auto &item : items) {
auto attr = dynamic_pointer_cast<SdpAttr>(item);
if (attr) {
auto dir = dynamic_pointer_cast<DirectionInterface>(attr->detail);
if (dir) {
return dir->getDirection();
}
}
}
return RtpDirection::invalid;
}
SdpItem::Ptr RtcSdpBase::getItem(char key_c, const char *attr_key) const {
for (auto item : items) {
string key(1, key_c);
if (strcasecmp(item->getKey(), key.data()) == 0) {
if (!attr_key) {
return item;
}
auto attr = dynamic_pointer_cast<SdpAttr>(item);
if (attr && !strcasecmp(attr->detail->getKey() , attr_key)) {
return attr->detail;
}
}
}
return SdpItem::Ptr();
}
int RtcSdpBase::getVersion() const {
return atoi(getStringItem('v').data());
}
SdpOrigin RtcSdpBase::getOrigin() const {
return getItemClass<SdpOrigin>('o');
}
string RtcSdpBase::getSessionName() const {
return getStringItem('s');
}
string RtcSdpBase::getSessionInfo() const {
return getStringItem('i');
}
SdpTime RtcSdpBase::getSessionTime() const{
return getItemClass<SdpTime>('t');
}
SdpConnection RtcSdpBase::getConnection() const {
return getItemClass<SdpConnection>('c');
}
SdpBandwidth RtcSdpBase::getBandwidth() const {
return getItemClass<SdpBandwidth>('b');
}
string RtcSdpBase::getUri() const {
return getStringItem('u');
}
string RtcSdpBase::getEmail() const {
return getStringItem('e');
}
string RtcSdpBase::getPhone() const {
return getStringItem('p');
}
string RtcSdpBase::getTimeZone() const {
return getStringItem('z');
}
string RtcSdpBase::getEncryptKey() const {
return getStringItem('k');
}
string RtcSdpBase::getRepeatTimes() const {
return getStringItem('r');
}
//////////////////////////////////////////////////////////////////////
void RtcSessionSdp::parse(const string &str) {
static auto flag = registerAllItem();
RtcSdpBase *media = nullptr;
auto lines = split(str, "\n");
for(auto &line : lines){
trim(line);
if(line.size() < 3 || line[1] != '='){
continue;
}
auto key = line.substr(0, 1);
auto value = line.substr(2);
if (!strcasecmp(key.data(), "m")) {
medias.emplace_back(RtcSdpBase());
media = &medias.back();
}
SdpItem::Ptr item;
auto it = sdpItemCreator.find(key);
if (it != sdpItemCreator.end()) {
item = it->second(key, value);
} else {
item = std::make_shared<SdpCommon>(key);
item->parse(value);
}
if (media) {
media->items.push_back(std::move(item));
} else {
items.push_back(std::move(item));
}
}
}
string RtcSessionSdp::toString() const {
_StrPrinter printer;
printer << RtcSdpBase::toString();
for (auto &media : medias) {
printer << media.toString();
}
return std::move(printer);
}
//////////////////////////////////////////////////////////////////////////////////////////
#define CHECK_SDP(exp) CHECK(exp, "解析sdp ", getKey(), " 字段失败:", str)
void SdpTime::parse(const string &str) {
CHECK_SDP(sscanf(str.data(), "%" SCNu64 " %" SCNu64, &start, &stop) == 2);
}
string SdpTime::toString() const {
if (value.empty()) {
value = to_string(start) + " " + to_string(stop);
}
return SdpItem::toString();
}
void SdpOrigin::parse(const string &str) {
auto vec = split(str, " ");
CHECK_SDP(vec.size() == 6);
username = vec[0];
session_id = vec[1];
session_version = vec[2];
nettype = vec[3];
addrtype = vec[4];
address = vec[5];
}
string SdpOrigin::toString() const {
if (value.empty()) {
value = username + " " + session_id + " " + session_version + " " + nettype + " " + addrtype + " " + address;
}
return SdpItem::toString();
}
void SdpConnection::parse(const string &str) {
auto vec = split(str, " ");
CHECK_SDP(vec.size() == 3);
nettype = vec[0];
addrtype = vec[1];
address = vec[2];
}
string SdpConnection::toString() const {
if (value.empty()) {
value = nettype + " " + addrtype + " " + address;
}
return SdpItem::toString();
}
void SdpBandwidth::parse(const string &str) {
auto vec = split(str, ":");
CHECK_SDP(vec.size() == 2);
bwtype = vec[0];
bandwidth = atoi(vec[1].data());
}
string SdpBandwidth::toString() const {
if (value.empty()) {
value = bwtype + ":" + to_string(bandwidth);
}
return SdpItem::toString();
}
void SdpMedia::parse(const string &str) {
auto vec = split(str, " ");
CHECK_SDP(vec.size() >= 4);
type = getTrackType(vec[0]);
CHECK_SDP(type != TrackInvalid);
port = atoi(vec[1].data());
proto = vec[2];
for (size_t i = 3; i < vec.size(); ++i) {
auto pt = atoi(vec[i].data());
CHECK_SDP(type == TrackApplication || pt <= 0xFF);
fmts.emplace_back(pt);
}
}
string SdpMedia::toString() const {
if (value.empty()) {
value = string(getTrackString(type)) + " " + to_string(port) + " " + proto;
for (auto fmt : fmts) {
value += ' ';
value += to_string(fmt);
}
}
return SdpItem::toString();
}
void SdpAttr::parse(const string &str) {
auto pos = str.find(':');
auto key = pos == string::npos ? str : str.substr(0, pos);
auto value = pos == string::npos ? string() : str.substr(pos + 1);
auto it = sdpItemCreator.find(key);
if (it != sdpItemCreator.end()) {
detail = it->second(key, value);
} else {
detail = std::make_shared<SdpCommon>(key);
detail->parse(value);
}
}
string SdpAttr::toString() const {
if (value.empty()) {
auto detail_value = detail->toString();
if (detail_value.empty()) {
value = detail->getKey();
} else {
value = string(detail->getKey()) + ":" + detail_value;
}
}
return SdpItem::toString();
}
void SdpAttrGroup::parse(const string &str) {
auto vec = split(str, " ");
CHECK_SDP(vec.size() >= 2);
type = vec[0];
vec.erase(vec.begin());
mids = std::move(vec);
}
string SdpAttrGroup::toString() const {
if (value.empty()) {
value = type;
for (auto mid : mids) {
value += ' ';
value += mid;
}
}
return SdpItem::toString();
}
void SdpAttrMsidSemantic::parse(const string &str) {
auto vec = split(str, " ");
CHECK_SDP(vec.size() >= 1);
msid = vec[0];
token = vec.size() > 1 ? vec[1] : "";
}
string SdpAttrMsidSemantic::toString() const {
if (value.empty()) {
if (token.empty()) {
value = string(" ") + msid;
} else {
value = string(" ") + msid + " " + token;
}
}
return SdpItem::toString();
}
void SdpAttrRtcp::parse(const string &str) {
auto vec = split(str, " ");
CHECK_SDP(vec.size() == 4);
port = atoi(vec[0].data());
nettype = vec[1];
addrtype = vec[2];
address = vec[3];
}
string SdpAttrRtcp::toString() const {
if (value.empty()) {
value = to_string(port) + " " + nettype + " " + addrtype + " " + address;
}
return SdpItem::toString();
}
void SdpAttrIceOption::parse(const string &str){
auto vec = split(str, " ");
for (auto &v : vec) {
if (!strcasecmp(v.data(), "trickle")) {
trickle = true;
continue;
}
if (!strcasecmp(v.data(), "renomination")) {
renomination = true;
continue;
}
}
}
string SdpAttrIceOption::toString() const{
if (value.empty()) {
if (trickle && renomination) {
value = "trickle renomination";
} else if (trickle) {
value = "trickle";
} else if (renomination) {
value = "renomination";
}
}
return value;
}
void SdpAttrFingerprint::parse(const string &str) {
auto vec = split(str, " ");
CHECK_SDP(vec.size() == 2);
algorithm = vec[0];
hash = vec[1];
}
string SdpAttrFingerprint::toString() const {
if (value.empty()) {
value = algorithm + " " + hash;
}
return SdpItem::toString();
}
void SdpAttrSetup::parse(const string &str) {
role = getDtlsRole(str);
CHECK_SDP(role != DtlsRole::invalid);
}
string SdpAttrSetup::toString() const {
if (value.empty()) {
value = getDtlsRoleString(role);
}
return SdpItem::toString();
}
void SdpAttrExtmap::parse(const string &str) {
char buf[128] = {0};
char direction_buf[32] = {0};
if (sscanf(str.data(), "%" SCNd8 "/%31[^ ] %127s", &id, direction_buf, buf) != 3) {
CHECK_SDP(sscanf(str.data(), "%" SCNd8 " %127s", &id, buf) == 2);
direction = RtpDirection::sendrecv;
} else {
direction = getRtpDirection(direction_buf);
}
ext = buf;
}
string SdpAttrExtmap::toString() const {
if (value.empty()) {
if(direction == RtpDirection::invalid || direction == RtpDirection::sendrecv){
value = to_string((int)id) + " " + ext;
} else {
value = to_string((int)id) + "/" + getRtpDirectionString(direction) + " " + ext;
}
}
return SdpItem::toString();
}
void SdpAttrRtpMap::parse(const string &str) {
char buf[32] = {0};
if (sscanf(str.data(), "%" SCNu8 " %31[^/]/%" SCNd32 "/%" SCNd32, &pt, buf, &sample_rate, &channel) != 4) {
CHECK_SDP(sscanf(str.data(), "%" SCNu8 " %31[^/]/%" SCNd32, &pt, buf, &sample_rate) == 3);
if (getTrackType(getCodecId(buf)) == TrackAudio) {
//未指定通道数时且为音频时那么通道数默认为1
channel = 1;
}
}
codec = buf;
}
string SdpAttrRtpMap::toString() const {
if (value.empty()) {
value = to_string(pt) + " " + codec + "/" + to_string(sample_rate);
if (channel) {
value += '/';
value += to_string(channel);
}
}
return SdpItem::toString();
}
void SdpAttrRtcpFb::parse(const string &str_in) {
auto str = str_in + "\n";
char rtcp_type_buf[32] = {0};
CHECK_SDP(sscanf(str.data(), "%" SCNu8 " %31[^\n]", &pt, rtcp_type_buf) == 2);
rtcp_type = rtcp_type_buf;
}
string SdpAttrRtcpFb::toString() const {
if (value.empty()) {
value = to_string(pt) + " " + rtcp_type;
}
return SdpItem::toString();
}
void SdpAttrFmtp::parse(const string &str) {
auto pos = str.find(' ');
CHECK_SDP(pos != string::npos);
pt = atoi(str.substr(0, pos).data());
auto vec = split(str.substr(pos + 1), ";");
for (auto &item : vec) {
trim(item);
auto pos = item.find('=');
if(pos == string::npos){
fmtp.emplace(std::make_pair(item, ""));
} else {
fmtp.emplace(std::make_pair(item.substr(0, pos), item.substr(pos + 1)));
}
}
CHECK_SDP(!fmtp.empty());
}
string SdpAttrFmtp::toString() const {
if (value.empty()) {
value = to_string(pt);
int i = 0;
for (auto &pr : fmtp) {
value += (i++ ? ';' : ' ');
value += pr.first + "=" + pr.second;
}
}
return SdpItem::toString();
}
void SdpAttrSSRC::parse(const string &str_in) {
auto str = str_in + '\n';
char attr_buf[32] = {0};
char attr_val_buf[128] = {0};
if (3 == sscanf(str.data(), "%" SCNu32 " %31[^:]:%127[^\n]", &ssrc, attr_buf, attr_val_buf)) {
attribute = attr_buf;
attribute_value = attr_val_buf;
} else if (2 == sscanf(str.data(), "%" SCNu32 " %31s[^\n]", &ssrc, attr_buf)) {
attribute = attr_buf;
} else {
CHECK_SDP(0);
}
}
string SdpAttrSSRC::toString() const {
if (value.empty()) {
value = to_string(ssrc) + ' ';
value += attribute;
if (!attribute_value.empty()) {
value += ':';
value += attribute_value;
}
}
return SdpItem::toString();
}
void SdpAttrSSRCGroup::parse(const string &str) {
auto vec = split(str, " ");
CHECK_SDP(vec.size() >= 3);
type = std::move(vec[0]);
CHECK(isFID() || isSIM());
vec.erase(vec.begin());
for (auto ssrc : vec) {
ssrcs.emplace_back((uint32_t) atoll(ssrc.data()));
}
}
string SdpAttrSSRCGroup::toString() const {
if (value.empty()) {
value = type;
//最少要求2个ssrc
CHECK(ssrcs.size() >= 2);
for (auto &ssrc : ssrcs) {
value += ' ';
value += to_string(ssrc);
}
}
return SdpItem::toString();
}
void SdpAttrSctpMap::parse(const string &str) {
char subtypes_buf[64] = {0};
CHECK_SDP(3 == sscanf(str.data(), "%" SCNu16 " %63[^ ] %" SCNd32, &port, subtypes_buf, &streams));
subtypes = subtypes_buf;
}
string SdpAttrSctpMap::toString() const {
if (value.empty()) {
value = to_string(port);
value += ' ';
value += subtypes;
value += ' ';
value += to_string(streams);
}
return SdpItem::toString();
}
void SdpAttrCandidate::parse(const string &str) {
char foundation_buf[40] = {0};
char transport_buf[16] = {0};
char address_buf[32] = {0};
char type_buf[16] = {0};
// https://datatracker.ietf.org/doc/html/rfc5245#section-15.1
CHECK_SDP(sscanf(str.data(), "%32[^ ] %" SCNu32 " %15[^ ] %" SCNu32 " %31[^ ] %" SCNu16 " typ %15[^ ]",
foundation_buf, &component, transport_buf, &priority, address_buf, &port, type_buf) == 7);
foundation = foundation_buf;
transport = transport_buf;
address = address_buf;
type = type_buf;
auto pos = str.find(type);
if (pos != string::npos) {
auto remain = str.substr(pos + type.size());
trim(remain);
if (!remain.empty()) {
auto vec = split(remain, " ");
string key;
for (auto &item : vec) {
if (key.empty()) {
key = item;
} else {
arr.emplace_back(std::make_pair(std::move(key), std::move(item)));
}
}
}
}
}
string SdpAttrCandidate::toString() const {
if (value.empty()) {
value = foundation + " " + to_string(component) + " " + transport + " " + to_string(priority) +
" " + address + " " + to_string(port) + " typ " + type;
for (auto &pr : arr) {
value += ' ';
value += pr.first;
value += ' ';
value += pr.second;
}
}
return SdpItem::toString();
}
void SdpAttrSimulcast::parse(const string &str) {
//https://www.meetecho.com/blog/simulcast-janus-ssrc/
//a=simulcast:send/recv q;h;f
//a=simulcast:send/recv [rid=]q;h;f
//a=simulcast: recv h;m;l
//
auto vec = split(str, " ");
CHECK_SDP(vec.size() == 2);
direction = vec[0];
rids = split(vec[1], ";");
}
string SdpAttrSimulcast::toString() const {
if (value.empty()) {
value = direction + " ";
bool first = true;
for (auto &rid : rids) {
if (first) {
first = false;
} else {
value += ';';
}
value += rid;
}
}
return SdpItem::toString();
}
void SdpAttrRid::parse(const string &str) {
auto vec = split(str, " ");
CHECK(vec.size() >= 2);
rid = vec[0];
direction = vec[1];
}
string SdpAttrRid::toString() const {
if (value.empty()) {
value = rid + " " + direction;
}
return SdpItem::toString();
}
void RtcSession::loadFrom(const string &str) {
RtcSessionSdp sdp;
sdp.parse(str);
version = sdp.getVersion();
origin = sdp.getOrigin();
session_name = sdp.getSessionName();
session_info = sdp.getSessionInfo();
connection = sdp.getConnection();
bandwidth = sdp.getBandwidth();
time = sdp.getSessionTime();
msid_semantic = sdp.getItemClass<SdpAttrMsidSemantic>('a', "msid-semantic");
for (auto &media : sdp.medias) {
auto mline = media.getItemClass<SdpMedia>('m');
this->media.emplace_back();
auto &rtc_media = this->media.back();
rtc_media.mid = media.getStringItem('a', "mid");
rtc_media.proto = mline.proto;
rtc_media.type = mline.type;
rtc_media.port = mline.port;
rtc_media.addr = media.getItemClass<SdpConnection>('c');
rtc_media.ice_ufrag = media.getStringItem('a', "ice-ufrag");
rtc_media.ice_pwd = media.getStringItem('a', "ice-pwd");
rtc_media.role = media.getItemClass<SdpAttrSetup>('a', "setup").role;
rtc_media.fingerprint = media.getItemClass<SdpAttrFingerprint>('a', "fingerprint");
if (rtc_media.fingerprint.empty()) {
rtc_media.fingerprint = sdp.getItemClass<SdpAttrFingerprint>('a', "fingerprint");
}
rtc_media.ice_lite = media.getItem('a', "ice-lite").operator bool();
auto ice_options = media.getItemClass<SdpAttrIceOption>('a', "ice-options");
rtc_media.ice_trickle = ice_options.trickle;
rtc_media.ice_renomination = ice_options.renomination;
rtc_media.candidate = media.getAllItem<SdpAttrCandidate>('a', "candidate");
if (mline.type == TrackType::TrackApplication) {
rtc_media.sctp_port = atoi(media.getStringItem('a', "sctp-port").data());
rtc_media.sctpmap = media.getItemClass<SdpAttrSctpMap>('a', "sctpmap");
continue;
}
rtc_media.rtcp_addr = media.getItemClass<SdpAttrRtcp>('a', "rtcp");
rtc_media.direction = media.getDirection();
rtc_media.extmap = media.getAllItem<SdpAttrExtmap>('a', "extmap");
rtc_media.rtcp_mux = media.getItem('a', "rtcp-mux").operator bool();
rtc_media.rtcp_rsize = media.getItem('a', "rtcp-rsize").operator bool();
map<uint32_t, RtcSSRC> rtc_ssrc_map;
auto ssrc_attr = media.getAllItem<SdpAttrSSRC>('a', "ssrc");
for (auto &ssrc : ssrc_attr) {
auto &rtc_ssrc = rtc_ssrc_map[ssrc.ssrc];
rtc_ssrc.ssrc = ssrc.ssrc;
if (!strcasecmp(ssrc.attribute.data(), "cname")) {
rtc_ssrc.cname = ssrc.attribute_value;
continue;
}
if (!strcasecmp(ssrc.attribute.data(), "msid")) {
rtc_ssrc.msid = ssrc.attribute_value;
continue;
}
if (!strcasecmp(ssrc.attribute.data(), "mslabel")) {
rtc_ssrc.mslabel = ssrc.attribute_value;
continue;
}
if (!strcasecmp(ssrc.attribute.data(), "label")) {
rtc_ssrc.label = ssrc.attribute_value;
continue;
}
}
auto ssrc_groups = media.getAllItem<SdpAttrSSRCGroup>('a', "ssrc-group");
bool have_rtx_ssrc = false;
SdpAttrSSRCGroup *ssrc_group_sim = nullptr;
for (auto &group : ssrc_groups) {
if (group.isFID()) {
have_rtx_ssrc = true;
//ssrc-group:FID字段必须包含rtp/rtx的ssrc
CHECK(group.ssrcs.size() == 2);
//根据rtp ssrc找到对象
auto it = rtc_ssrc_map.find(group.ssrcs[0]);
CHECK(it != rtc_ssrc_map.end());
//设置rtx ssrc
it->second.rtx_ssrc = group.ssrcs[1];
rtc_media.rtp_rtx_ssrc.emplace_back(it->second);
} else if (group.isSIM()) {
CHECK(!ssrc_group_sim);
ssrc_group_sim = &group;
}
}
if (!have_rtx_ssrc) {
//按照sdp顺序依次添加ssrc
for (auto &attr : ssrc_attr) {
if (attr.attribute == "cname") {
rtc_media.rtp_rtx_ssrc.emplace_back(rtc_ssrc_map[attr.ssrc]);
}
}
}
auto simulcast = media.getItemClass<SdpAttrSimulcast>('a', "simulcast");
if (!simulcast.empty()) {
// a=rid:h send
// a=rid:m send
// a=rid:l send
// a=simulcast:send h;m;l
// 风格的simulcast
unordered_set<string> rid_map;
for (auto &rid : simulcast.rids) {
rid_map.emplace(rid);
}
for (auto &rid : media.getAllItem<SdpAttrRid>('a', "rid")) {
CHECK(rid.direction == simulcast.direction);
CHECK(rid_map.find(rid.rid) != rid_map.end());
}
//simulcast最少要求2种方案
CHECK(simulcast.rids.size() >= 2);
rtc_media.rtp_rids = simulcast.rids;
}
if (ssrc_group_sim) {
//指定了a=ssrc-group:SIM
for (auto ssrc : ssrc_group_sim->ssrcs) {
auto it = rtc_ssrc_map.find(ssrc);
CHECK(it != rtc_ssrc_map.end());
rtc_media.rtp_ssrc_sim.emplace_back(it->second);
}
} else if (!rtc_media.rtp_rids.empty()) {
//未指定a=ssrc-group:SIM, 但是指定了a=simulcast, 那么只能根据ssrc顺序来对应rid顺序
rtc_media.rtp_ssrc_sim = rtc_media.rtp_rtx_ssrc;
}
if (!rtc_media.supportSimulcast()) {
//不支持simulcast的情况下最多一组ssrc
CHECK(rtc_media.rtp_rtx_ssrc.size() <= 1);
} else {
//simulcast的情况下要么没有指定ssrc要么指定的ssrc个数与rid个数一致
CHECK(rtc_media.rtp_ssrc_sim.empty() || rtc_media.rtp_ssrc_sim.size() == rtc_media.rtp_rids.size());
}
auto rtpmap_arr = media.getAllItem<SdpAttrRtpMap>('a', "rtpmap");
auto rtcpfb_arr = media.getAllItem<SdpAttrRtcpFb>('a', "rtcp-fb");
auto fmtp_aar = media.getAllItem<SdpAttrFmtp>('a', "fmtp");
//方便根据pt查找rtpmap,一个pt必有一条
map<uint8_t, SdpAttrRtpMap &> rtpmap_map;
//方便根据pt查找rtcp-fb,一个pt可能有多条或0条
multimap<uint8_t, SdpAttrRtcpFb &> rtcpfb_map;
//方便根据pt查找fmtp一个pt最多一条
map<uint8_t, SdpAttrFmtp &> fmtp_map;
for (auto &rtpmap : rtpmap_arr) {
//添加失败,有多条
CHECK(rtpmap_map.emplace(rtpmap.pt, rtpmap).second, "该pt存在多条a=rtpmap:", (int)rtpmap.pt);
}
for (auto &rtpfb : rtcpfb_arr) {
rtcpfb_map.emplace(rtpfb.pt, rtpfb);
}
for (auto &fmtp : fmtp_aar) {
//添加失败,有多条
CHECK(fmtp_map.emplace(fmtp.pt, fmtp).second, "该pt存在多条a=fmtp:", (int)fmtp.pt);
}
for (auto &pt : mline.fmts) {
//遍历所有编码方案的pt
rtc_media.plan.emplace_back();
auto &plan = rtc_media.plan.back();
auto rtpmap_it = rtpmap_map.find(pt);
if (rtpmap_it == rtpmap_map.end()) {
plan.pt = pt;
plan.codec = RtpPayload::getName(pt);
plan.sample_rate = RtpPayload::getClockRate(pt);
plan.channel = RtpPayload::getAudioChannel(pt);
} else {
plan.pt = rtpmap_it->second.pt;
plan.codec = rtpmap_it->second.codec;
plan.sample_rate = rtpmap_it->second.sample_rate;
plan.channel = rtpmap_it->second.channel;
}
auto fmtp_it = fmtp_map.find(pt);
if (fmtp_it != fmtp_map.end()) {
plan.fmtp = fmtp_it->second.fmtp;
}
for (auto rtpfb_it = rtcpfb_map.find(pt);
rtpfb_it != rtcpfb_map.end() && rtpfb_it->second.pt == pt; ++rtpfb_it) {
plan.rtcp_fb.emplace(rtpfb_it->second.rtcp_type);
}
}
}
group = sdp.getItemClass<SdpAttrGroup>('a', "group");
}
std::shared_ptr<SdpItem> wrapSdpAttr(SdpItem::Ptr item){
auto ret = std::make_shared<SdpAttr>();
ret->detail = std::move(item);
return ret;
}
static void toRtsp(vector <SdpItem::Ptr> &items) {
for (auto it = items.begin(); it != items.end();) {
switch ((*it)->getKey()[0]) {
case 'v':
case 'o':
case 's':
case 'i':
case 't':
case 'c':
case 'b':{
++it;
break;
}
case 'm': {
auto m = dynamic_pointer_cast<SdpMedia>(*it);
CHECK(m);
m->proto = "RTP/AVP";
++it;
break;
}
case 'a': {
auto attr = dynamic_pointer_cast<SdpAttr>(*it);
CHECK(attr);
if (!strcasecmp(attr->detail->getKey(), "rtpmap")
|| !strcasecmp(attr->detail->getKey(), "fmtp")) {
++it;
break;
}
}
default: {
it = items.erase(it);
break;
}
}
}
}
string RtcSession::toRtspSdp() const{
RtcSession copy = *this;
copy.media.clear();
for (auto &m : media) {
switch (m.type) {
case TrackAudio:
case TrackVideo: {
if (m.direction != RtpDirection::inactive) {
copy.media.emplace_back(m);
copy.media.back().plan.resize(1);
}
break;
}
default: continue;
}
}
CHECK(!copy.media.empty());
auto sdp = copy.toRtcSessionSdp();
toRtsp(sdp->items);
int i = 0;
for (auto &m : sdp->medias) {
toRtsp(m.items);
m.items.push_back(wrapSdpAttr(std::make_shared<SdpCommon>("control", string("trackID=") + to_string(i++))));
}
return sdp->toString();
}
void addSdpAttrSSRC(const RtcSSRC &rtp_ssrc, vector<SdpItem::Ptr> &items, uint32_t ssrc_num) {
assert(ssrc_num);
SdpAttrSSRC ssrc;
ssrc.ssrc = ssrc_num;
ssrc.attribute = "cname";
ssrc.attribute_value = rtp_ssrc.cname;
items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrSSRC>(ssrc)));
if (!rtp_ssrc.msid.empty()) {
ssrc.attribute = "msid";
ssrc.attribute_value = rtp_ssrc.msid;
items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrSSRC>(ssrc)));
}
if (!rtp_ssrc.mslabel.empty()) {
ssrc.attribute = "mslabel";
ssrc.attribute_value = rtp_ssrc.mslabel;
items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrSSRC>(ssrc)));
}
if (!rtp_ssrc.label.empty()) {
ssrc.attribute = "label";
ssrc.attribute_value = rtp_ssrc.label;
items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrSSRC>(ssrc)));
}
}
RtcSessionSdp::Ptr RtcSession::toRtcSessionSdp() const{
RtcSessionSdp::Ptr ret = std::make_shared<RtcSessionSdp>();
auto &sdp = *ret;
sdp.items.emplace_back(std::make_shared<SdpString<'v'> >(to_string(version)));
sdp.items.emplace_back(std::make_shared<SdpOrigin>(origin));
sdp.items.emplace_back(std::make_shared<SdpString<'s'> >(session_name));
if (!session_info.empty()) {
sdp.items.emplace_back(std::make_shared<SdpString<'i'> >(session_info));
}
sdp.items.emplace_back(std::make_shared<SdpTime>(time));
if(connection.empty()){
sdp.items.emplace_back(std::make_shared<SdpConnection>(connection));
}
if (!bandwidth.empty()) {
sdp.items.emplace_back(std::make_shared<SdpBandwidth>(bandwidth));
}
sdp.items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrGroup>(group)));
sdp.items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrMsidSemantic>(msid_semantic)));
for (auto &m : media) {
sdp.medias.emplace_back();
auto &sdp_media = sdp.medias.back();
auto mline = std::make_shared<SdpMedia>();
mline->type = m.type;
mline->port = m.port;
mline->proto = m.proto;
for (auto &p : m.plan) {
mline->fmts.emplace_back(p.pt);
}
if (m.type == TrackApplication) {
mline->fmts.emplace_back(m.sctp_port);
}
sdp_media.items.emplace_back(std::move(mline));
sdp_media.items.emplace_back(std::make_shared<SdpConnection>(m.addr));
if (!m.rtcp_addr.empty()) {
sdp_media.items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrRtcp>(m.rtcp_addr)));
}
sdp_media.items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrIceUfrag>(m.ice_ufrag)));
sdp_media.items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrIcePwd>(m.ice_pwd)));
if (m.ice_trickle || m.ice_renomination) {
auto attr = std::make_shared<SdpAttrIceOption>();
attr->trickle = m.ice_trickle;
attr->renomination = m.ice_renomination;
sdp_media.items.emplace_back(wrapSdpAttr(attr));
}
sdp_media.items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrFingerprint>(m.fingerprint)));
sdp_media.items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrSetup>(m.role)));
sdp_media.items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrMid>(m.mid)));
if (m.ice_lite) {
sdp_media.items.emplace_back(wrapSdpAttr(std::make_shared<SdpCommon>("ice-lite")));
}
for (auto &ext : m.extmap) {
sdp_media.items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrExtmap>(ext)));
}
if (m.direction != RtpDirection::invalid) {
sdp_media.items.emplace_back(wrapSdpAttr(std::make_shared<DirectionInterfaceImp>(m.direction)));
}
if (m.rtcp_mux) {
sdp_media.items.emplace_back(wrapSdpAttr(std::make_shared<SdpCommon>("rtcp-mux")));
}
if (m.rtcp_rsize) {
sdp_media.items.emplace_back(wrapSdpAttr(std::make_shared<SdpCommon>("rtcp-rsize")));
}
if(m.type != TrackApplication) {
for (auto &p : m.plan) {
auto rtp_map = std::make_shared<SdpAttrRtpMap>();
rtp_map->pt = p.pt;
rtp_map->codec = p.codec;
rtp_map->sample_rate = p.sample_rate;
rtp_map->channel = p.channel;
//添加a=rtpmap
sdp_media.items.emplace_back(wrapSdpAttr(std::move(rtp_map)));
for (auto &fb : p.rtcp_fb) {
auto rtcp_fb = std::make_shared<SdpAttrRtcpFb>();
rtcp_fb->pt = p.pt;
rtcp_fb->rtcp_type = fb;
//添加a=rtcp-fb
sdp_media.items.emplace_back(wrapSdpAttr(std::move(rtcp_fb)));
}
if (!p.fmtp.empty()) {
auto fmtp = std::make_shared<SdpAttrFmtp>();
fmtp->pt = p.pt;
fmtp->fmtp = p.fmtp;
//添加a=fmtp
sdp_media.items.emplace_back(wrapSdpAttr(std::move(fmtp)));
}
}
{
//添加a=msid字段
if (!m.rtp_rtx_ssrc.empty()) {
auto msid = std::make_shared<SdpAttrMsid>();
if (!m.rtp_rtx_ssrc[0].msid.empty()) {
msid->parse(m.rtp_rtx_ssrc[0].msid);
} else {
msid->parse("mslabel label");
}
sdp_media.items.emplace_back(wrapSdpAttr(std::move(msid)));
}
}
{
for (auto &ssrc : m.rtp_rtx_ssrc) {
//添加a=ssrc字段
CHECK(!ssrc.empty());
addSdpAttrSSRC(ssrc, sdp_media.items, ssrc.ssrc);
if (ssrc.rtx_ssrc) {
addSdpAttrSSRC(ssrc, sdp_media.items, ssrc.rtx_ssrc);
//生成a=ssrc-group:FID字段
//有rtx ssrc
auto group = std::make_shared<SdpAttrSSRCGroup>();
group->type = "FID";
group->ssrcs.emplace_back(ssrc.ssrc);
group->ssrcs.emplace_back(ssrc.rtx_ssrc);
sdp_media.items.emplace_back(wrapSdpAttr(std::move(group)));
}
}
}
{
if (m.rtp_ssrc_sim.size() >= 2) {
//simulcast 要求 2~3路
auto group = std::make_shared<SdpAttrSSRCGroup>();
for (auto &ssrc : m.rtp_ssrc_sim) {
group->ssrcs.emplace_back(ssrc.ssrc);
}
//添加a=ssrc-group:SIM字段
group->type = "SIM";
sdp_media.items.emplace_back(wrapSdpAttr(std::move(group)));
}
if (m.rtp_rids.size() >= 2) {
auto simulcast = std::make_shared<SdpAttrSimulcast>();
simulcast->direction = "recv";
simulcast->rids = m.rtp_rids;
sdp_media.items.emplace_back(wrapSdpAttr(std::move(simulcast)));
for (auto &rid : m.rtp_rids) {
auto attr_rid = std::make_shared<SdpAttrRid>();
attr_rid->rid = rid;
attr_rid->direction = "recv";
sdp_media.items.emplace_back(wrapSdpAttr(std::move(attr_rid)));
}
}
}
} else {
sdp_media.items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrSctpMap>(m.sctpmap)));
sdp_media.items.emplace_back(wrapSdpAttr(std::make_shared<SdpCommon>("sctp-port", to_string(m.sctp_port))));
}
for (auto &cand : m.candidate) {
sdp_media.items.emplace_back(wrapSdpAttr(std::make_shared<SdpAttrCandidate>(cand)));
}
}
return ret;
}
string RtcSession::toString() const{
return toRtcSessionSdp()->toString();
}
string RtcCodecPlan::getFmtp(const char *key) const{
for (auto &item : fmtp) {
if (strcasecmp(item.first.data(), key) == 0) {
return item.second;
}
}
return "";
}
const RtcCodecPlan *RtcMedia::getPlan(uint8_t pt) const{
for (auto &item : plan) {
if (item.pt == pt) {
return &item;
}
}
return nullptr;
}
const RtcCodecPlan *RtcMedia::getPlan(const char *codec) const{
for (auto &item : plan) {
if (strcasecmp(item.codec.data(), codec) == 0) {
return &item;
}
}
return nullptr;
}
const RtcCodecPlan *RtcMedia::getRelatedRtxPlan(uint8_t pt) const{
for (auto &item : plan) {
if (strcasecmp(item.codec.data(), "rtx") == 0) {
auto apt = atoi(item.getFmtp("apt").data());
if (pt == apt) {
return &item;
}
}
}
return nullptr;
}
uint32_t RtcMedia::getRtpSSRC() const {
if (rtp_rtx_ssrc.size()) {
return rtp_rtx_ssrc[0].ssrc;
}
return 0;
}
uint32_t RtcMedia::getRtxSSRC() const {
if (rtp_rtx_ssrc.size()) {
return rtp_rtx_ssrc[0].rtx_ssrc;
}
return 0;
}
bool RtcMedia::supportSimulcast() const {
if (!rtp_rids.empty()) {
return true;
}
if (!rtp_ssrc_sim.empty()) {
return true;
}
return false;
}
void RtcMedia::checkValid() const{
CHECK(type != TrackInvalid);
CHECK(!mid.empty());
CHECK(!proto.empty());
CHECK(direction != RtpDirection::invalid || type == TrackApplication);
CHECK(!plan.empty() || type == TrackApplication);
CHECK(type == TrackApplication || rtcp_mux, "只支持rtcp-mux模式");
bool send_rtp = (direction == RtpDirection::sendonly || direction == RtpDirection::sendrecv);
if (rtp_rids.empty() && rtp_ssrc_sim.empty()) {
//非simulcast时检查有没有指定rtp ssrc
CHECK(!rtp_rtx_ssrc.empty() || !send_rtp);
}
#if 0
//todo 发现Firefox(88.0)在mac平台下开启rtx后没有指定ssrc
auto rtx_plan = getPlan("rtx");
if (rtx_plan) {
//开启rtx后必须指定rtx_ssrc
CHECK(rtp_rtx_ssrc.size() >= 2 || !send_rtp);
}
#endif
}
void RtcSession::checkValid() const{
CHECK(version == 0);
CHECK(!origin.empty());
CHECK(!session_name.empty());
CHECK(!msid_semantic.empty());
CHECK(!media.empty());
CHECK(!group.mids.empty() && group.mids.size() <= media.size(), "只支持group BUNDLE模式");
bool have_active_media = false;
for (auto &item : media) {
item.checkValid();
switch (item.direction) {
case RtpDirection::sendrecv:
case RtpDirection::sendonly:
case RtpDirection::recvonly: have_active_media = true; break;
default : break;
}
}
CHECK(have_active_media, "必须确保最少有一个活跃的track");
}
const RtcMedia *RtcSession::getMedia(TrackType type) const{
for(auto &m : media){
if(m.type == type){
return &m;
}
}
return nullptr;
}
bool RtcSession::supportRtcpFb(const string &name, TrackType type) const {
auto media = getMedia(type);
if (!media) {
return false;
}
auto &ref = media->plan[0].rtcp_fb;
return ref.find(name) != ref.end();
}
bool RtcSession::supportSimulcast() const {
for (auto &m : media) {
if (m.supportSimulcast()) {
return true;
}
}
return false;
}
string const SdpConst::kTWCCRtcpFb = "transport-cc";
string const SdpConst::kRembRtcpFb = "goog-remb";
void RtcConfigure::RtcTrackConfigure::enableTWCC(bool enable){
if (!enable) {
rtcp_fb.erase(SdpConst::kTWCCRtcpFb);
extmap.erase(RtpExtType::transport_cc);
} else {
rtcp_fb.emplace(SdpConst::kTWCCRtcpFb);
extmap.emplace(RtpExtType::transport_cc, RtpDirection::sendrecv);
}
}
void RtcConfigure::RtcTrackConfigure::enableREMB(bool enable){
if (!enable) {
rtcp_fb.erase(SdpConst::kRembRtcpFb);
extmap.erase(RtpExtType::abs_send_time);
} else {
rtcp_fb.emplace(SdpConst::kRembRtcpFb);
extmap.emplace(RtpExtType::abs_send_time, RtpDirection::sendrecv);
}
}
static vector<CodecId> toCodecArray(const string &str){
vector<CodecId> ret;
auto vec = split(str, ",");
for (auto &s : vec) {
auto codec = getCodecId(trim(s));
if (codec != CodecInvalid) {
ret.emplace_back(codec);
}
}
return ret;
}
void RtcConfigure::RtcTrackConfigure::setDefaultSetting(TrackType type){
rtcp_mux = true;
rtcp_rsize = false;
group_bundle = true;
support_rtx = true;
support_red = false;
support_ulpfec = false;
ice_lite = true;
ice_trickle = true;
ice_renomination = false;
switch (type) {
case TrackAudio: {
//此处调整偏好的编码格式优先级
GET_CONFIG_FUNC(vector<CodecId>, s_preferred_codec, RTC::kPreferredCodecA, toCodecArray);
CHECK(!s_preferred_codec.empty(), "rtc音频偏好codec不能为空");
preferred_codec = s_preferred_codec;
rtcp_fb = {SdpConst::kTWCCRtcpFb, SdpConst::kRembRtcpFb};
extmap = {
{RtpExtType::ssrc_audio_level, RtpDirection::sendrecv},
{RtpExtType::csrc_audio_level, RtpDirection::sendrecv},
{RtpExtType::abs_send_time, RtpDirection::sendrecv},
{RtpExtType::transport_cc, RtpDirection::sendrecv},
//rtx重传rtp时忽略sdes_mid类型的rtp ext,实测发现Firefox在接收rtx时如果存在sdes_mid的ext,将导致无法播放
//{RtpExtType::sdes_mid,RtpDirection::sendrecv},
{RtpExtType::sdes_rtp_stream_id, RtpDirection::sendrecv},
{RtpExtType::sdes_repaired_rtp_stream_id, RtpDirection::sendrecv}
};
break;
}
case TrackVideo: {
//此处调整偏好的编码格式优先级
GET_CONFIG_FUNC(vector<CodecId>, s_preferred_codec, RTC::kPreferredCodecV, toCodecArray);
CHECK(!s_preferred_codec.empty(), "rtc视频偏好codec不能为空");
preferred_codec = s_preferred_codec;
rtcp_fb = {SdpConst::kTWCCRtcpFb, SdpConst::kRembRtcpFb, "nack", "ccm fir", "nack pli"};
extmap = {
{RtpExtType::abs_send_time, RtpDirection::sendrecv},
{RtpExtType::transport_cc, RtpDirection::sendrecv},
//rtx重传rtp时忽略sdes_mid类型的rtp ext,实测发现Firefox在接收rtx时如果存在sdes_mid的ext,将导致无法播放
//{RtpExtType::sdes_mid,RtpDirection::sendrecv},
{RtpExtType::sdes_rtp_stream_id, RtpDirection::sendrecv},
{RtpExtType::sdes_repaired_rtp_stream_id, RtpDirection::sendrecv},
{RtpExtType::video_timing, RtpDirection::sendrecv},
{RtpExtType::color_space, RtpDirection::sendrecv},
{RtpExtType::video_content_type, RtpDirection::sendrecv},
{RtpExtType::playout_delay, RtpDirection::sendrecv},
{RtpExtType::video_orientation, RtpDirection::sendrecv},
{RtpExtType::toffset, RtpDirection::sendrecv},
{RtpExtType::framemarking, RtpDirection::sendrecv}
};
break;
}
case TrackApplication: {
break;
}
default: break;
}
}
void RtcConfigure::setDefaultSetting(string ice_ufrag, string ice_pwd, RtpDirection direction,
const SdpAttrFingerprint &fingerprint) {
video.setDefaultSetting(TrackVideo);
audio.setDefaultSetting(TrackAudio);
application.setDefaultSetting(TrackApplication);
video.ice_ufrag = audio.ice_ufrag = application.ice_ufrag = std::move(ice_ufrag);
video.ice_pwd = audio.ice_pwd = application.ice_pwd = std::move(ice_pwd);
video.direction = audio.direction = application.direction = direction;
video.fingerprint = audio.fingerprint = application.fingerprint = fingerprint;
}
void RtcConfigure::addCandidate(const SdpAttrCandidate &candidate, TrackType type) {
switch (type) {
case TrackAudio: {
audio.candidate.emplace_back(candidate);
break;
}
case TrackVideo: {
video.candidate.emplace_back(candidate);
break;
}
case TrackApplication: {
application.candidate.emplace_back(candidate);
break;
}
default: {
if (audio.group_bundle) {
audio.candidate.emplace_back(candidate);
}
if (video.group_bundle) {
video.candidate.emplace_back(candidate);
}
if (application.group_bundle) {
application.candidate.emplace_back(candidate);
}
break;
}
}
}
void RtcConfigure::enableTWCC(bool enable, TrackType type){
switch (type) {
case TrackAudio: {
audio.enableTWCC(enable);
break;
}
case TrackVideo: {
video.enableTWCC(enable);
break;
}
case TrackApplication: {
application.enableTWCC(enable);
break;
}
default: {
audio.enableTWCC(enable);
video.enableTWCC(enable);
application.enableTWCC(enable);
break;
}
}
}
void RtcConfigure::enableREMB(bool enable, TrackType type){
switch (type) {
case TrackAudio: {
audio.enableREMB(enable);
break;
}
case TrackVideo: {
video.enableREMB(enable);
break;
}
case TrackApplication: {
application.enableREMB(enable);
break;
}
default: {
audio.enableREMB(enable);
video.enableREMB(enable);
application.enableREMB(enable);
break;
}
}
}
shared_ptr<RtcSession> RtcConfigure::createAnswer(const RtcSession &offer){
shared_ptr<RtcSession> ret = std::make_shared<RtcSession>();
ret->version = offer.version;
ret->origin = offer.origin;
ret->session_name = offer.session_name;
ret->msid_semantic = offer.msid_semantic;
matchMedia(ret, TrackAudio, offer.media, audio);
matchMedia(ret, TrackVideo, offer.media, video);
matchMedia(ret, TrackApplication, offer.media, application);
//设置音视频端口复用
if (!offer.group.mids.empty()) {
for (auto &m : ret->media) {
ret->group.mids.emplace_back(m.mid);
}
}
return ret;
}
static RtpDirection matchDirection(RtpDirection offer_direction, RtpDirection supported){
switch (offer_direction) {
case RtpDirection::sendonly : {
if (supported != RtpDirection::recvonly && supported != RtpDirection::sendrecv) {
//我们不支持接收
return RtpDirection::inactive;
}
return RtpDirection::recvonly;
}
case RtpDirection::recvonly : {
if (supported != RtpDirection::sendonly && supported != RtpDirection::sendrecv) {
//我们不支持发送
return RtpDirection::inactive;
}
return RtpDirection::sendonly;
}
//对方支持发送接收,那么最终能力根据配置来决定
case RtpDirection::sendrecv : return (supported == RtpDirection::invalid ? RtpDirection::inactive : supported);
case RtpDirection::inactive : return RtpDirection::inactive;
default: return RtpDirection::invalid;
}
}
void RtcConfigure::matchMedia(const shared_ptr<RtcSession> &ret, TrackType type, const vector<RtcMedia> &medias, const RtcTrackConfigure &configure){
bool check_profile = true;
bool check_codec = true;
RETRY:
for (auto &codec : configure.preferred_codec) {
for (auto &offer_media : medias) {
if (offer_media.type != type) {
continue;
}
if (offer_media.ice_lite && configure.ice_lite) {
WarnL << "answer sdp配置为ice_lite模式与offer sdp中的ice_lite模式冲突";
continue;
}
const RtcCodecPlan *selected_plan = nullptr;
for (auto &plan : offer_media.plan) {
//先检查编码格式是否为偏好
if (check_codec && getCodecId(plan.codec) != codec) {
continue;
}
//命中偏好的编码格式,然后检查规格
if (check_profile && !onCheckCodecProfile(plan, codec)) {
continue;
}
//找到中意的codec
selected_plan = &plan;
break;
}
if (!selected_plan) {
//offer中该媒体的所有的codec都不支持
continue;
}
RtcMedia answer_media;
answer_media.type = offer_media.type;
answer_media.mid = offer_media.mid;
answer_media.proto = offer_media.proto;
answer_media.port = offer_media.port;
answer_media.addr = offer_media.addr;
answer_media.rtcp_addr = offer_media.rtcp_addr;
answer_media.rtcp_mux = offer_media.rtcp_mux && configure.rtcp_mux;
answer_media.rtcp_rsize = offer_media.rtcp_rsize && configure.rtcp_rsize;
answer_media.ice_trickle = offer_media.ice_trickle && configure.ice_trickle;
answer_media.ice_renomination = offer_media.ice_renomination && configure.ice_renomination;
answer_media.ice_ufrag = configure.ice_ufrag;
answer_media.ice_pwd = configure.ice_pwd;
answer_media.fingerprint = configure.fingerprint;
answer_media.ice_lite = configure.ice_lite;
answer_media.candidate = configure.candidate;
answer_media.rtp_rids = offer_media.rtp_rids;
switch (offer_media.role) {
case DtlsRole::actpass :
case DtlsRole::active : {
answer_media.role = DtlsRole::passive;
break;
}
case DtlsRole::passive : {
answer_media.role = DtlsRole::active;
break;
}
default: continue;
}
//如果codec匹配失败那么禁用该track
answer_media.direction = check_codec ? matchDirection(offer_media.direction, configure.direction)
: RtpDirection::inactive;
if (answer_media.direction == RtpDirection::invalid) {
continue;
}
if (answer_media.direction == RtpDirection::sendrecv) {
//如果是收发双向那么我们拷贝offer sdp的ssrc确保ssrc一致
answer_media.rtp_rtx_ssrc = offer_media.rtp_rtx_ssrc;
}
//添加媒体plan
answer_media.plan.emplace_back(*selected_plan);
onSelectPlan(answer_media.plan.back(), codec);
set<uint8_t> pt_selected = {selected_plan->pt};
//添加rtx,red,ulpfec plan
if (configure.support_red || configure.support_rtx || configure.support_ulpfec) {
for (auto &plan : offer_media.plan) {
if (!strcasecmp(plan.codec.data(), "rtx")) {
if (configure.support_rtx && atoi(plan.getFmtp("apt").data()) == selected_plan->pt) {
answer_media.plan.emplace_back(plan);
pt_selected.emplace(plan.pt);
}
continue;
}
if (!strcasecmp(plan.codec.data(), "red")) {
if (configure.support_red) {
answer_media.plan.emplace_back(plan);
pt_selected.emplace(plan.pt);
}
continue;
}
if (!strcasecmp(plan.codec.data(), "ulpfec")) {
if (configure.support_ulpfec) {
answer_media.plan.emplace_back(plan);
pt_selected.emplace(plan.pt);
}
continue;
}
}
}
//对方和我方都支持的扩展,那么我们才支持
for (auto &ext : offer_media.extmap) {
auto it = configure.extmap.find(RtpExt::getExtType(ext.ext));
if (it != configure.extmap.end()) {
auto new_dir = matchDirection(ext.direction, it->second);
switch (new_dir) {
case RtpDirection::invalid:
case RtpDirection::inactive: continue;
default: break;
}
answer_media.extmap.emplace_back(ext);
answer_media.extmap.back().direction = new_dir;
}
}
auto &rtcp_fb_ref = answer_media.plan[0].rtcp_fb;
rtcp_fb_ref.clear();
//对方和我方都支持的rtcpfb那么我们才支持
for (auto &fp : selected_plan->rtcp_fb) {
if (configure.rtcp_fb.find(fp) != configure.rtcp_fb.end()) {
//对方该rtcp被我们支持
rtcp_fb_ref.emplace(fp);
}
}
#if 0
//todo 此处为添加无效的planwebrtc sdp通过调节plan pt顺序选择匹配的codec意味着后面的codec其实放在sdp中是无意义的
for (auto &plan : offer_media.plan) {
if (pt_selected.find(plan.pt) == pt_selected.end()) {
answer_media.plan.emplace_back(plan);
}
}
#endif
ret->media.emplace_back(answer_media);
return;
}
}
if (check_profile) {
//如果是由于检查profile导致匹配失败那么重试一次且不检查profile
check_profile = false;
goto RETRY;
}
if (check_codec) {
//如果是由于检查codec导致匹配失败那么重试一次且不检查codec
check_codec = false;
goto RETRY;
}
}
void RtcConfigure::setPlayRtspInfo(const string &sdp){
RtcSession session;
video.direction = RtpDirection::inactive;
audio.direction = RtpDirection::inactive;
session.loadFrom(sdp);
for (auto &m : session.media) {
switch (m.type) {
case TrackVideo : {
video.direction = RtpDirection::sendonly;
_rtsp_video_plan = std::make_shared<RtcCodecPlan>(m.plan[0]);
video.preferred_codec.clear();
video.preferred_codec.emplace_back(getCodecId(_rtsp_video_plan->codec));
break;
}
case TrackAudio : {
audio.direction = RtpDirection::sendonly;
_rtsp_audio_plan = std::make_shared<RtcCodecPlan>(m.plan[0]);
audio.preferred_codec.clear();
audio.preferred_codec.emplace_back(getCodecId(_rtsp_audio_plan->codec));
break;
}
default: break;
}
}
}
static const string kProfile{"profile-level-id"};
static const string kMode{"packetization-mode"};
bool RtcConfigure::onCheckCodecProfile(const RtcCodecPlan &plan, CodecId codec){
if (_rtsp_audio_plan && codec == getCodecId(_rtsp_audio_plan->codec)) {
if (plan.sample_rate != _rtsp_audio_plan->sample_rate || plan.channel != _rtsp_audio_plan->channel) {
//音频采样率和通道数必须相同
return false;
}
return true;
}
if (_rtsp_video_plan && codec == CodecH264 && getCodecId(_rtsp_video_plan->codec) == CodecH264) {
//h264时profile-level-id
if (strcasecmp(_rtsp_video_plan->fmtp[kProfile].data(), const_cast<RtcCodecPlan &>(plan).fmtp[kProfile].data())) {
//profile-level-id 不匹配
return false;
}
return true;
}
return true;
}
void RtcConfigure::onSelectPlan(RtcCodecPlan &plan, CodecId codec){
if (_rtsp_video_plan && codec == CodecH264 && getCodecId(_rtsp_video_plan->codec) == CodecH264) {
//h264时设置packetization-mod为一致
auto mode = _rtsp_video_plan->fmtp[kMode];
plan.fmtp[kMode] = mode.empty() ? "0" : mode;
}
}