Parse the connection data in SDP (c= line).

webrtc/p2p/base/sessiondescription.h

 /*
  *  Copyright 2004 The WebRTC Project Authors. All rights reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
 #ifndef WEBRTC_P2P_BASE_SESSIONDESCRIPTION_H_
 #define WEBRTC_P2P_BASE_SESSIONDESCRIPTION_H_
 
 #include <string>
 #include <vector>
 
+#include "webrtc/base/constructormagic.h"
+#include "webrtc/base/optional.h"
+#include "webrtc/base/socketaddress.h"
 #include "webrtc/p2p/base/transportinfo.h"
-#include "webrtc/base/constructormagic.h"
 
 namespace cricket {
 
 // Describes a session content. Individual content types inherit from
 // this class.  Analagous to a <jingle><content><description> or
 // <session><description>.
 class ContentDescription {
  public:
   virtual ~ContentDescription() {}
   virtual ContentDescription* Copy() const = 0;
@@ skipping 144 matching lines @@
 
   // Group mutators.
   void AddGroup(const ContentGroup& group) { content_groups_.push_back(group); }
   // Remove the first group with the same semantics specified by |name|.
   void RemoveGroupByName(const std::string& name);
 
   // Global attributes.
   void set_msid_supported(bool supported) { msid_supported_ = supported; }
   bool msid_supported() const { return msid_supported_; }
 
+  void set_session_connection_addr(

[Taylor Brandstetter, 2017/03/10 22:41:17]

I think it would be simpler to only store this address in
MediaContentDescription. If a "c=" is found at the session level, its value can
just be copied to the media level, since the meaning is the same.

This is what currently happens with ice-ufrag at the session level (for
example):
https://cs.chromium.org/chromium/src/third_party/webrtc/pc/webrtcsdp.cc?type=...

[Zhi Huang, 2017/03/15 04:04:59]

Done.

+      const rtc::Optional<rtc::SocketAddress>& addr) {
+    session_connection_addr_ = addr;
+  }
+  rtc::Optional<rtc::SocketAddress> session_connection_addr() {
+    return session_connection_addr_;
+  }
+
  private:
   ContentInfos contents_;
   TransportInfos transport_infos_;
   ContentGroups content_groups_;
   bool msid_supported_ = true;
+  // https://tools.ietf.org/html/rfc4566#page-21
+  // The session level connection data indicating the address of the remote
+  // endpoint.
+  rtc::Optional<rtc::SocketAddress> session_connection_addr_;
 };
 
 // Indicates whether a ContentDescription was an offer or an answer, as
 // described in http://www.ietf.org/rfc/rfc3264.txt. CA_UPDATE
 // indicates a jingle update message which contains a subset of a full
 // session description
 enum ContentAction {
   CA_OFFER, CA_PRANSWER, CA_ANSWER, CA_UPDATE
 };
 
 // Indicates whether a ContentDescription was sent by the local client
 // or received from the remote client.
 enum ContentSource {
   CS_LOCAL, CS_REMOTE
 };
 
 }  // namespace cricket
 
 #endif  // WEBRTC_P2P_BASE_SESSIONDESCRIPTION_H_