From 7737917886db51d74d5a9336e3893d05baa15454 Mon Sep 17 00:00:00 2001
From: xqing2003 <xqing2007@gmail.com>
Date: Fri, 1 Jun 2018 23:30:30 +0800
Subject: [PATCH 1/3] solve memory leak

---
 src/linux_tcp/tcpconnection.cpp | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/src/linux_tcp/tcpconnection.cpp b/src/linux_tcp/tcpconnection.cpp
index b8f0cd1..184dabf 100644
--- a/src/linux_tcp/tcpconnection.cpp
+++ b/src/linux_tcp/tcpconnection.cpp
@@ -70,13 +70,20 @@ void TcpConnection::process(int fd, int flags)
     auto *result = _state->process(monitor, fd, flags);
 
     // are we still valid
-    if (!monitor.valid()) return;
+    if (!monitor.valid()) 
+    {
+        delete result;
+        return;
+    }
 
     // skip if the same state is continued to be used, or when the process()
     // method returns nullptr (which only happens when the object is destructed,
     // and "this" is no longer valid)
-    if (!result || result == _state.get()) return;
-
+    if (!result || result == _state.get()) 
+    {
+        delete result;
+        return;
+    }
     // replace it with the new implementation
     _state.reset(result);
 }

From e40006058ed06bfb643a76718734d4d486f00411 Mon Sep 17 00:00:00 2001
From: xqing2003 <xqing2007@gmail.com>
Date: Wed, 6 Jun 2018 22:11:55 +0800
Subject: [PATCH 2/3] fix memory leak

fix memory leak when channel error
---
 src/linux_tcp/tcpconnection.cpp | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/src/linux_tcp/tcpconnection.cpp b/src/linux_tcp/tcpconnection.cpp
index 184dabf..8513de7 100644
--- a/src/linux_tcp/tcpconnection.cpp
+++ b/src/linux_tcp/tcpconnection.cpp
@@ -70,7 +70,7 @@ void TcpConnection::process(int fd, int flags)
     auto *result = _state->process(monitor, fd, flags);
 
     // are we still valid
-    if (!monitor.valid()) 
+    if (!monitor.valid() &&  result != _state.get()) 
     {
         delete result;
         return;
@@ -79,11 +79,7 @@ void TcpConnection::process(int fd, int flags)
     // skip if the same state is continued to be used, or when the process()
     // method returns nullptr (which only happens when the object is destructed,
     // and "this" is no longer valid)
-    if (!result || result == _state.get()) 
-    {
-        delete result;
-        return;
-    }
+    if (!result || result == _state.get()) return;
     // replace it with the new implementation
     _state.reset(result);
 }

From 2430da76c3b29b2c785ec07a02079022561e62b0 Mon Sep 17 00:00:00 2001
From: Emiel Bruijntjes <emiel.bruijntjes@copernica.com>
Date: Sun, 10 Jun 2018 20:46:11 +0200
Subject: [PATCH 3/3] refactored code

---
 src/linux_tcp/tcpconnection.cpp | 31 +++++++++++++++++++------------
 1 file changed, 19 insertions(+), 12 deletions(-)

diff --git a/src/linux_tcp/tcpconnection.cpp b/src/linux_tcp/tcpconnection.cpp
index 8513de7..80e2430 100644
--- a/src/linux_tcp/tcpconnection.cpp
+++ b/src/linux_tcp/tcpconnection.cpp
@@ -66,22 +66,29 @@ void TcpConnection::process(int fd, int flags)
     // monitor the object for destruction, because you never know what the user
     Monitor monitor(this);
 
+    // store the old state
+    auto *oldstate = _state.get();
+
     // pass on the the state, that returns a new impl
-    auto *result = _state->process(monitor, fd, flags);
+    auto *newstate = _state->process(monitor, fd, flags);
 
-    // are we still valid
-    if (!monitor.valid() &&  result != _state.get()) 
+    // if the state did not change, we do not have to update a member,
+    // when the newstate is nullptr, the object is (being) destructed
+    // and we do not have to do anything else either
+    if (oldstate == newstate || newstate == nullptr) return;
+
+    // in a bizarre set of circumstances, the user may have implemented the
+    // handler in such a way that the connection object was destructed
+    if (!monitor.valid()) 
     {
-        delete result;
-        return;
+        // ok, user code is weird, connection object no longer exist, get rid of the state too
+        delete newstate;
+    }
+    else
+    {
+        // replace it with the new implementation
+        _state.reset(newstate);
     }
-
-    // skip if the same state is continued to be used, or when the process()
-    // method returns nullptr (which only happens when the object is destructed,
-    // and "this" is no longer valid)
-    if (!result || result == _state.get()) return;
-    // replace it with the new implementation
-    _state.reset(result);
 }
 
 /**