From 22622e91a9c9eb7a83047da3b974f9c7573ff898 Mon Sep 17 00:00:00 2001
From: Michael Davidsaver <mdavidsaver@gmail.com>
Date: Wed, 13 Feb 2019 21:06:19 -0800
Subject: [PATCH] server: detect duplicate channelCreated() calls

---
 src/server/pv/responseHandlers.h | 1 +
 src/server/responseHandlers.cpp  | 7 +++++--
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/server/pv/responseHandlers.h b/src/server/pv/responseHandlers.h
index b8f62b0..305ee7f 100644
--- a/src/server/pv/responseHandlers.h
+++ b/src/server/pv/responseHandlers.h
@@ -218,6 +218,7 @@ private:
     const std::string _channelName;
     const pvAccessID _cid;
     ChannelSecuritySession::shared_pointer const & _css;
+    bool _created;
     epics::pvData::Status _status;
     epics::pvData::Mutex _mutex;
 };
diff --git a/src/server/responseHandlers.cpp b/src/server/responseHandlers.cpp
index 81412be..a00e3fe 100644
--- a/src/server/responseHandlers.cpp
+++ b/src/server/responseHandlers.cpp
@@ -792,8 +792,7 @@ ServerChannelRequesterImpl::ServerChannelRequesterImpl(const Transport::shared_p
     _channelName(channelName),
     _cid(cid),
     _css(css),
-    _status(),
-    _mutex()
+    _created(false)
 {
 }
 
@@ -811,6 +810,8 @@ ChannelRequester::shared_pointer ServerChannelRequesterImpl::create(
 
 void ServerChannelRequesterImpl::channelCreated(const Status& status, Channel::shared_pointer const & channel)
 {
+    if(_created)
+        throw std::logic_error("Channel already created");
     if(detail::BlockingServerTCPTransportCodec::shared_pointer transport = _transport.lock())
     {
         ServerChannel::shared_pointer serverChannel;
@@ -847,6 +848,7 @@ void ServerChannelRequesterImpl::channelCreated(const Status& status, Channel::s
                 Lock guard(_mutex);
                 _status = status;
                 _serverChannel = serverChannel;
+                _created = true;
             }
 
             TransportSender::shared_pointer thisSender = shared_from_this();
@@ -891,6 +893,7 @@ void ServerChannelRequesterImpl::channelStateChange(Channel::shared_pointer cons
         ServerChannel::shared_pointer channel;
         {
             Lock guard(_mutex);
+            _created = false;
             channel= dynamic_pointer_cast<ServerChannel>(_serverChannel.lock());
         }