Rename PeerConnection::Error to PeerConnection::SessionError

Also renames methods for interacting with the session error. This
clarifies the scope of this error type and lets methods have a
local variable named |error| without confusing it with the
|error()| getter.

Bug: webrtc:8587
Change-Id: I90e6eed24d961abbce15e56a76a8793ff1a806ea
Reviewed-on: https://webrtc-review.googlesource.com/27124
Commit-Queue: Steve Anton <steveanton@webrtc.org>
Reviewed-by: Peter Thatcher <pthatcher@webrtc.org>
Reviewed-by: Zhi Huang <zhihuang@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#21060}

pc/peerconnection.cc

@@ -576,24 +576,6 @@ std::string BadStateErrMsg(PeerConnectionInterface::SignalingState state) {
   return desc.str();
 }
 
-#define GET_STRING_OF_ERROR_CODE(err) \
-  case webrtc::PeerConnection::err:   \
-    result = #err;                    \
-    break;
-
-std::string GetErrorCodeString(webrtc::PeerConnection::Error err) {
-  std::string result;
-  switch (err) {
-    GET_STRING_OF_ERROR_CODE(ERROR_NONE)
-    GET_STRING_OF_ERROR_CODE(ERROR_CONTENT)
-    GET_STRING_OF_ERROR_CODE(ERROR_TRANSPORT)
-    default:
-      RTC_NOTREACHED();
-      break;
-  }
-  return result;
-}
-
 std::string MakeErrorString(const std::string& error, const std::string& desc) {
   std::ostringstream ret;
   ret << error << " " << desc;
@@ -3446,7 +3428,7 @@ bool PeerConnection::SetCurrentOrPendingLocalDescription(
   }
 
   pending_ice_restarts_.clear();
-  if (error() != ERROR_NONE) {
+  if (session_error() != SessionError::kNone) {
     return BadLocalSdp(local_description()->type(), GetSessionErrorMsg(),
                        err_desc);
   }
@@ -3535,7 +3517,7 @@ bool PeerConnection::SetCurrentOrPendingRemoteDescription(
     }
   }
 
-  if (error() != ERROR_NONE) {
+  if (session_error() != SessionError::kNone) {
     return BadRemoteSdp(remote_description()->type(), GetSessionErrorMsg(),
                         err_desc);
   }
@@ -3572,11 +3554,12 @@ std::vector<cricket::BaseChannel*> PeerConnection::Channels() const {
   return channels;
 }
 
-void PeerConnection::SetError(Error error, const std::string& error_desc) {
+void PeerConnection::SetSessionError(SessionError error,
-  RTC_DCHECK(signaling_thread()->IsCurrent());
+                                     const std::string& error_desc) {
-  if (error != error_) {
+  RTC_DCHECK_RUN_ON(signaling_thread());
-    error_ = error;
+  if (error != session_error_) {
-    error_desc_ = error_desc;
+    session_error_ = error;
+    session_error_desc_ = error_desc;
   }
 }
 
@@ -3587,7 +3570,7 @@ bool PeerConnection::UpdateSessionState(Action action,
 
   // If there's already a pending error then no state transition should happen.
   // But all call-sites should be verifying this before calling us!
-  RTC_DCHECK(error() == ERROR_NONE);
+  RTC_DCHECK(session_error() == SessionError::kNone);
   std::string td_err;
   if (action == kOffer) {
     if (!PushdownTransportDescription(source, cricket::CA_OFFER, &td_err)) {
@@ -3597,9 +3580,9 @@ bool PeerConnection::UpdateSessionState(Action action,
                              ? PeerConnectionInterface::kHaveLocalOffer
                              : PeerConnectionInterface::kHaveRemoteOffer);
     if (!PushdownMediaDescription(cricket::CA_OFFER, source, err_desc)) {
-      SetError(ERROR_CONTENT, *err_desc);
+      SetSessionError(SessionError::kContent, *err_desc);
     }
-    if (error() != ERROR_NONE) {
+    if (session_error() != SessionError::kNone) {
       return BadOfferSdp(source, GetSessionErrorMsg(), err_desc);
     }
   } else if (action == kPrAnswer) {
@@ -3611,9 +3594,9 @@ bool PeerConnection::UpdateSessionState(Action action,
                              ? PeerConnectionInterface::kHaveLocalPrAnswer
                              : PeerConnectionInterface::kHaveRemotePrAnswer);
     if (!PushdownMediaDescription(cricket::CA_PRANSWER, source, err_desc)) {
-      SetError(ERROR_CONTENT, *err_desc);
+      SetSessionError(SessionError::kContent, *err_desc);
     }
-    if (error() != ERROR_NONE) {
+    if (session_error() != SessionError::kNone) {
       return BadPranswerSdp(source, GetSessionErrorMsg(), err_desc);
     }
   } else if (action == kAnswer) {
@@ -3640,9 +3623,9 @@ bool PeerConnection::UpdateSessionState(Action action,
     EnableChannels();
     ChangeSignalingState(PeerConnectionInterface::kStable);
     if (!PushdownMediaDescription(cricket::CA_ANSWER, source, err_desc)) {
-      SetError(ERROR_CONTENT, *err_desc);
+      SetSessionError(SessionError::kContent, *err_desc);
     }
-    if (error() != ERROR_NONE) {
+    if (session_error() != SessionError::kNone) {
       return BadAnswerSdp(source, GetSessionErrorMsg(), err_desc);
     }
   }
@@ -4044,7 +4027,7 @@ void PeerConnection::OnCertificateReady(
 }
 
 void PeerConnection::OnDtlsSrtpSetupFailure(cricket::BaseChannel*, bool rtcp) {
-  SetError(ERROR_TRANSPORT,
+  SetSessionError(SessionError::kTransport,
                   rtcp ? kDtlsSrtpSetupFailureRtcp : kDtlsSrtpSetupFailureRtp);
 }
 
@@ -4651,7 +4634,7 @@ bool PeerConnection::ValidateSessionDescription(
     cricket::ContentSource source,
     std::string* err_desc) {
   std::string type;
-  if (error() != ERROR_NONE) {
+  if (session_error() != SessionError::kNone) {
     return BadSdp(source, type, GetSessionErrorMsg(), err_desc);
   }
 
@@ -4738,10 +4721,23 @@ bool PeerConnection::ExpectSetRemoteDescription(Action action) {
   }
 }
 
+const char* PeerConnection::SessionErrorToString(SessionError error) const {
+  switch (error) {
+    case SessionError::kNone:
+      return "ERROR_NONE";
+    case SessionError::kContent:
+      return "ERROR_CONTENT";
+    case SessionError::kTransport:
+      return "ERROR_TRANSPORT";
+  }
+  RTC_NOTREACHED();
+  return "";
+}
+
 std::string PeerConnection::GetSessionErrorMsg() {
   std::ostringstream desc;
-  desc << kSessionError << GetErrorCodeString(error()) << ". ";
+  desc << kSessionError << SessionErrorToString(session_error()) << ". ";
-  desc << kSessionErrorDesc << error_desc() << ".";
+  desc << kSessionErrorDesc << session_error_desc() << ".";
   return desc.str();
 }
 

pc/peerconnection.h

@@ -278,12 +278,6 @@ class PeerConnection : public PeerConnectionInterface,
   // factory, it shouldn't really be public).
   bool GetSslRole(const std::string& content_name, rtc::SSLRole* role);
 
-  enum Error {
-    ERROR_NONE = 0,       // no error
-    ERROR_CONTENT = 1,    // channel errors in SetLocalContent/SetRemoteContent
-    ERROR_TRANSPORT = 2,  // transport error of some kind
-  };
-
  protected:
   ~PeerConnection() override;
 
@@ -557,9 +551,15 @@ class PeerConnection : public PeerConnectionInterface,
     kAnswer,
   };
 
+  enum class SessionError {
+    kNone,       // No error.
+    kContent,    // Error in BaseChannel SetLocalContent/SetRemoteContent.
+    kTransport,  // Error from the underlying transport.
+  };
+
   // Returns the last error in the session. See the enum above for details.
-  Error error() const { return error_; }
+  SessionError session_error() const { return session_error_; }
-  const std::string& error_desc() const { return error_desc_; }
+  const std::string& session_error_desc() const { return session_error_desc_; }
 
   cricket::BaseChannel* GetChannel(const std::string& content_name);
 
@@ -616,7 +616,7 @@ class PeerConnection : public PeerConnectionInterface,
   }
 
   // Updates the error state, signaling if necessary.
-  void SetError(Error error, const std::string& error_desc);
+  void SetSessionError(SessionError error, const std::string& error_desc);
 
   bool UpdateSessionState(Action action,
                           cricket::ContentSource source,
@@ -750,6 +750,7 @@ class PeerConnection : public PeerConnectionInterface,
       const std::vector<cricket::Candidate>& candidates);
   void OnTransportControllerDtlsHandshakeError(rtc::SSLHandshakeError error);
 
+  const char* SessionErrorToString(SessionError error) const;
   std::string GetSessionErrorMsg();
 
   // Invoked when TransportController connection completion is signaled.
@@ -833,8 +834,8 @@ class PeerConnection : public PeerConnectionInterface,
       rtc::scoped_refptr<RtpTransceiverProxyWithInternal<RtpTransceiver>>>
       transceivers_;
 
-  Error error_ = ERROR_NONE;
+  SessionError session_error_ = SessionError::kNone;
-  std::string error_desc_;
+  std::string session_error_desc_;
 
   std::string session_id_;
   rtc::Optional<bool> initial_offerer_;