From b5cb19b37c361a263a9cec2e2fb356d16520afd1 Mon Sep 17 00:00:00 2001
From: deadbeef <deadbeef@webrtc.org>
Date: Mon, 23 Nov 2015 16:39:12 -0800
Subject: [PATCH] Fixing direction attribute in answer for non-RTP protocols.

"non-RTP protocols" refers to SCTP data channels. Because
there are no streams for SCTP data channels, the answer was being
set to RECVONLY.

BUG=webrtc:5228

Review URL: https://codereview.webrtc.org/1473013002

Cr-Commit-Position: refs/heads/master@{#10762}
---
 talk/app/webrtc/peerconnection_unittest.cc | 34 ++++++++++++++++++++--
 talk/session/media/mediasession.cc         | 21 ++++++++-----
 2 files changed, 46 insertions(+), 9 deletions(-)

diff --git a/talk/app/webrtc/peerconnection_unittest.cc b/talk/app/webrtc/peerconnection_unittest.cc
index 6307bfc6d8..6dc83a5751 100644
--- a/talk/app/webrtc/peerconnection_unittest.cc
+++ b/talk/app/webrtc/peerconnection_unittest.cc
@@ -1450,8 +1450,9 @@ TEST_F(MAYBE_JsepPeerConnectionP2PTestClient, GetDtls12Recv) {
                                           kDefaultSrtpCryptoSuite));
 }
 
-// This test sets up a call between two parties with audio, video and data.
-TEST_F(MAYBE_JsepPeerConnectionP2PTestClient, LocalP2PTestDataChannel) {
+// This test sets up a call between two parties with audio, video and an RTP
+// data channel.
+TEST_F(MAYBE_JsepPeerConnectionP2PTestClient, LocalP2PTestRtpDataChannel) {
   FakeConstraints setup_constraints;
   setup_constraints.SetAllowRtpDataChannels();
   ASSERT_TRUE(CreateTestClients(&setup_constraints, &setup_constraints));
@@ -1481,6 +1482,35 @@ TEST_F(MAYBE_JsepPeerConnectionP2PTestClient, LocalP2PTestDataChannel) {
   EXPECT_FALSE(receiving_client()->data_observer()->IsOpen());
 }
 
+// This test sets up a call between two parties with audio, video and an SCTP
+// data channel.
+TEST_F(MAYBE_JsepPeerConnectionP2PTestClient, LocalP2PTestSctpDataChannel) {
+  ASSERT_TRUE(CreateTestClients());
+  initializing_client()->CreateDataChannel();
+  LocalP2PTest();
+  ASSERT_TRUE(initializing_client()->data_channel() != nullptr);
+  EXPECT_TRUE_WAIT(receiving_client()->data_channel() != nullptr, kMaxWaitMs);
+  EXPECT_TRUE_WAIT(initializing_client()->data_observer()->IsOpen(),
+                   kMaxWaitMs);
+  EXPECT_TRUE_WAIT(receiving_client()->data_observer()->IsOpen(), kMaxWaitMs);
+
+  std::string data = "hello world";
+
+  initializing_client()->data_channel()->Send(DataBuffer(data));
+  EXPECT_EQ_WAIT(data, receiving_client()->data_observer()->last_message(),
+                 kMaxWaitMs);
+
+  receiving_client()->data_channel()->Send(DataBuffer(data));
+  EXPECT_EQ_WAIT(data, initializing_client()->data_observer()->last_message(),
+                 kMaxWaitMs);
+
+  receiving_client()->data_channel()->Close();
+  // Send new offer and answer.
+  receiving_client()->Negotiate();
+  EXPECT_FALSE(initializing_client()->data_observer()->IsOpen());
+  EXPECT_FALSE(receiving_client()->data_observer()->IsOpen());
+}
+
 // This test sets up a call between two parties and creates a data channel.
 // The test tests that received data is buffered unless an observer has been
 // registered.
diff --git a/talk/session/media/mediasession.cc b/talk/session/media/mediasession.cc
index ed626e2f34..0e9730ce2b 100644
--- a/talk/session/media/mediasession.cc
+++ b/talk/session/media/mediasession.cc
@@ -633,6 +633,11 @@ static void PruneCryptos(const CryptoParamsVec& filter,
                         target_cryptos->end());
 }
 
+static bool IsRtpProtocol(const std::string& protocol) {
+  return protocol.empty() ||
+         (protocol.find(cricket::kMediaProtocolRtpPrefix) != std::string::npos);
+}
+
 static bool IsRtpContent(SessionDescription* sdesc,
                          const std::string& content_name) {
   bool is_rtp = false;
@@ -643,9 +648,7 @@ static bool IsRtpContent(SessionDescription* sdesc,
     if (!media_desc) {
       return false;
     }
-    is_rtp = media_desc->protocol().empty() ||
-             (media_desc->protocol().find(cricket::kMediaProtocolRtpPrefix) !=
-              std::string::npos);
+    is_rtp = IsRtpProtocol(media_desc->protocol());
   }
   return is_rtp;
 }
@@ -1067,12 +1070,16 @@ static bool CreateMediaContentAnswer(
       answer->set_direction(MD_RECVONLY);
       break;
     case MD_RECVONLY:
-      answer->set_direction(answer->streams().empty() ? MD_INACTIVE
-                                                      : MD_SENDONLY);
+      answer->set_direction(IsRtpProtocol(answer->protocol()) &&
+                                    answer->streams().empty()
+                                ? MD_INACTIVE
+                                : MD_SENDONLY);
       break;
     case MD_SENDRECV:
-      answer->set_direction(answer->streams().empty() ? MD_RECVONLY
-                                                      : MD_SENDRECV);
+      answer->set_direction(IsRtpProtocol(answer->protocol()) &&
+                                    answer->streams().empty()
+                                ? MD_RECVONLY
+                                : MD_SENDRECV);
       break;
     default:
       RTC_DCHECK(false && "MediaContentDescription has unexpected direction.");