From 26c5d0ecb8fe198d379326a34d8489cb5eb2bcd1 Mon Sep 17 00:00:00 2001
From: Yakun Xu <xyk@google.com>
Date: Wed, 23 Jan 2019 08:11:07 +0800
Subject: [PATCH] [border-agent] reuse Dtls restart (#3489)

`MeshCoP::Dtls` session will restart listening by itself. It's not
necessary for border agent to restart `MeshCoP::Dtls`.
---
 src/core/meshcop/border_agent.cpp | 45 +++++++------------------------
 src/core/meshcop/border_agent.hpp |  3 +--
 2 files changed, 10 insertions(+), 38 deletions(-)

diff --git a/src/core/meshcop/border_agent.cpp b/src/core/meshcop/border_agent.cpp
index 367664e63..817fa2ed6 100644
--- a/src/core/meshcop/border_agent.cpp
+++ b/src/core/meshcop/border_agent.cpp
@@ -641,32 +641,12 @@ void BorderAgent::HandleConnected(bool aConnected)
     }
     else
     {
-        ThreadNetif &     netif = GetNetif();
-        Coap::CoapSecure &coaps = netif.GetCoapSecure();
-
         otLogInfoMeshCoP("Commissioner disconnected");
-        netif.GetIp6().GetUdp().RemoveReceiver(mUdpReceiver);
-        netif.RemoveUnicastAddress(mCommissionerAloc);
-        coaps.Stop();
+        GetNetif().RemoveUnicastAddress(mCommissionerAloc);
         SetState(OT_BORDER_AGENT_STATE_STARTED);
-        mTimer.Start(kRestartDelay);
     }
 }
 
-otError BorderAgent::StartCoaps(void)
-{
-    ThreadNetif &     netif = GetNetif();
-    Coap::CoapSecure &coaps = netif.GetCoapSecure();
-    otError           error;
-
-    SuccessOrExit(error = coaps.Start(kBorderAgentUdpPort));
-    SuccessOrExit(error = coaps.SetPsk(netif.GetKeyManager().GetPSKc(), OT_PSKC_MAX_SIZE));
-    coaps.SetConnectedCallback(HandleConnected, this);
-
-exit:
-    return error;
-}
-
 otError BorderAgent::Start(void)
 {
     otError           error;
@@ -676,7 +656,9 @@ otError BorderAgent::Start(void)
 
     VerifyOrExit(mState == OT_BORDER_AGENT_STATE_STOPPED, error = OT_ERROR_ALREADY);
 
-    SuccessOrExit(error = StartCoaps());
+    SuccessOrExit(error = coaps.Start(kBorderAgentUdpPort));
+    SuccessOrExit(error = coaps.SetPsk(netif.GetKeyManager().GetPSKc(), OT_PSKC_MAX_SIZE));
+    coaps.SetConnectedCallback(HandleConnected, this);
 
     coaps.AddResource(mActiveGet);
     coaps.AddResource(mActiveSet);
@@ -706,24 +688,15 @@ void BorderAgent::HandleTimeout(void)
 {
     ThreadNetif &     netif = GetNetif();
     Coap::CoapSecure &coaps = netif.GetCoapSecure();
-    otError           error;
 
     if (coaps.IsConnected())
     {
-        error = coaps.Stop();
-        otLogWarnMeshCoP("Reset commissioner session: %s", otThreadErrorToString(error));
-    }
-    else if (!coaps.IsConnectionActive())
-    {
-        error = StartCoaps();
-        otLogWarnMeshCoP("Restart border agent secure CoAP service: %s", otThreadErrorToString(error));
-    }
-    else
-    {
-        assert(false);
-    }
+        otError error;
 
-    OT_UNUSED_VARIABLE(error);
+        error = coaps.Disconnect();
+        otLogWarnMeshCoP("Reset commissioner session: %s", otThreadErrorToString(error));
+        OT_UNUSED_VARIABLE(error);
+    }
 }
 
 otError BorderAgent::Stop(void)
diff --git a/src/core/meshcop/border_agent.hpp b/src/core/meshcop/border_agent.hpp
index 5ed81c23e..3af0855a7 100644
--- a/src/core/meshcop/border_agent.hpp
+++ b/src/core/meshcop/border_agent.hpp
@@ -88,8 +88,7 @@ private:
     {
         static_cast<BorderAgent *>(aContext)->HandleConnected(aConnected);
     }
-    void    HandleConnected(bool aConnected);
-    otError StartCoaps(void);
+    void HandleConnected(bool aConnected);
 
     template <Coap::Resource BorderAgent::*aResource>
     static void HandleRequest(void *aContext, otMessage *aMessage, const otMessageInfo *aMessageInfo)