[RESOLVED] Latest MS Update - changed http.sys - and now I'm getting strange behavior

[szlamany]

Ok - been working for a long time on an app - working a backend service. When I debug this app it starts 4 services in the IDE and they all talk via http to each other. This has been working great for 12 months now.

Upon getting the latest release of MS updates - which included lots of changes to http.sys - this code below stopped working as expected. It works 4 out of 5 times - but sometimes blows up.

In the FINALLY - where I check to see if the response isnot nothing - I go to close the response and get an error of:

            Finally
                If response IsNot Nothing Then
                    response.Close()
                End If
            End Try

"An operation was attempted on a nonexistent network connection". What is the proper way to see if the response needs to be closed? I've attached an image of the RESPONSE object on a watch window.

And why is it all of a sudden behaving this way. The packets are all still flowing as expected - the program still runs as expected from what I see. It's just this clean-up code not awlays working the same way.

            Dim response As HttpListenerResponse = Nothing
            Try
                If cl2.responseStart(request, FSOb, returnMessage) Then
                    With FSOb
                        Try
                            Using dcn As New SqlConnection(m_ConnStr)
                                Using cmd As New SqlCommand
                                    cmd.CommandType = CommandType.StoredProcedure
                                    cmd.CommandText = "Discovery_Load" ' "TagInfo_Load"
                                    cmd.Connection = dcn
                                    cmd.Parameters.AddWithValue("@GCId", .FileId)
.
.
.
                                    cmd.Parameters.AddWithValue("@TagInfo", strTI)
                                    dcn.Open()
                                    Dim strMessage As String = cmd.ExecuteScalar.ToString
                                End Using
                            End Using
                        Catch ex As Exception
                            'MessageBox.Show(ex.Message, "Archive Discovery_Load")
                        End Try
                    End With
.
.
.
                    rtnSize = cl2.responseEnd(response, context, FSOb, returnMessage)
                End If
            Catch ex As Exception
                returnMessage = ex.Message
            Finally
                If response IsNot Nothing Then
                    response.Close()
                End If
            End Try

cl2.responseStart looks like this

    Public Function responseStart(ByRef request As HttpListenerRequest, ByRef FSOb As FSObject, ByRef TraceMsg As String) As Boolean
        Dim blnSuccess As Boolean = True
        TraceMsg = ""
        Try
            Dim inputstream As Stream = request.InputStream()
            Deserialize(FSOb, inputstream)
            'FSOb.AffectCnt()
            TraceMsg = FSOb.DesiredAction
            If FSOb.FileId = 0 Then
                TraceMsg = "%Index " & FSOb.FileIndex.ToString & " " & FSOb.DesiredAction & " " & FSOb.WhoFrom & " (Rcvd " & CInt((request.ContentLength64 + 1024) / 1024).ToString & " KB)"
            Else
                TraceMsg = "F" & FSOb.FileId.ToString & " " & FSOb.DesiredAction & " " & FSOb.WhoFrom & " (Rcvd " & CInt((request.ContentLength64 + 1024) / 1024).ToString & " KB)" & tagList(FSOb)
            End If
            'If request.UserAgent = "search" Then
            If request.Headers("x-package") = "search" Then
                If FSOb.DesiredAction = "space" Then
                    TraceMsg &= " search/space=" & FSOb.FNTagsCollection(0)
                ElseIf FSOb.DesiredAction = "enter" Then
                    TraceMsg &= " search/enter=" & FSOb.FNTagsCollection(0)
                Else
                    TraceMsg &= " search=" & FSOb.FNTagsCollection(0)
                End If
            End If
            'If request.UserAgent = "searchdone" Then TraceMsg &= " narrowresult=" & FSOb.FNTagsCollection(0)
        Catch ex As HttpListenerException
            TraceMsg = ex.Message
            blnSuccess = False
        Catch ex As Exception
            TraceMsg = ex.Message
            blnSuccess = False
        End Try
        TraceMsg = System.Threading.Thread.CurrentThread.ManagedThreadId.ToString.PadLeft(2, "0"c) & " S)  " & TraceMsg
        Return blnSuccess
    End Function

and cl2.responseEnd looks like this

    Public Function responseEnd(ByRef response As HttpListenerResponse, ByRef context As HttpListenerContext, ByRef FSOb As FSObject, ByRef TraceMsg As String) As Long
        Dim rtnSize As Long = 0
        TraceMsg = ""
        Try
            'FSOb.AffectCnt()
            response = context.Response
            Dim output As System.IO.Stream = response.OutputStream
            Using fsMS As New MemoryStream
                Serialize(FSOb, fsMS)
                output.Write(fsMS.ToArray, 0, CInt(fsMS.Length))
                rtnSize = fsMS.Length
                If FSOb.ReaderRegistered Then
                    TraceMsg = FSOb.SessionId.ToString & ">F" & FSOb.FileId.ToString & " " & FSOb.DesiredAction & " " & FSOb.WhoFrom & " (Send " & CInt((fsMS.Length + 1024) / 1024).ToString & " KB)" & tagList(FSOb)
                Else
                    TraceMsg = FSOb.SessionId.ToString & ">F" & FSOb.FileId.ToString & " " & FSOb.DesiredAction & " " & FSOb.WhoFrom & " (Send " & CInt((fsMS.Length + 1024) / 1024).ToString & " KB)"
                End If
            End Using
        Catch ex As HttpListenerException
            TraceMsg = ex.Message
        Catch ex As Exception
            TraceMsg = ex.Message
        End Try
        TraceMsg = System.Threading.Thread.CurrentThread.ManagedThreadId.ToString.PadLeft(2, "0"c) & " E)  " & TraceMsg
        Return rtnSize
    End Function

[szlamany]

Found my problem - missing "output.Close()" in this function.

    Public Function responseEnd(ByRef response As HttpListenerResponse, ByRef context As HttpListenerContext, ByRef FSOb As FSObject, ByRef TraceMsg As String) As Long
        Dim rtnSize As Long = 0
        TraceMsg = ""
        Try
            'FSOb.AffectCnt()
            response = context.Response
            Dim output As System.IO.Stream = response.OutputStream
            Using fsMS As New MemoryStream
                Serialize(FSOb, fsMS)
                output.Write(fsMS.ToArray, 0, CInt(fsMS.Length))
                output.Close()
                rtnSize = fsMS.Length
                If FSOb.ReaderRegistered Then
                    TraceMsg = FSOb.SessionId.ToString & ">F" & FSOb.FileId.ToString & " " & FSOb.DesiredAction & " " & FSOb.WhoFrom & " (Send " & CInt((fsMS.Length + 1024) / 1024).ToString & " KB)" & tagList(FSOb)
                Else
                    TraceMsg = FSOb.SessionId.ToString & ">F" & FSOb.FileId.ToString & " " & FSOb.DesiredAction & " " & FSOb.WhoFrom & " (Send " & CInt((fsMS.Length + 1024) / 1024).ToString & " KB)"
                End If
            End Using
        Catch ex As HttpListenerException
            TraceMsg = ex.Message
        Catch ex As Exception
            TraceMsg = ex.Message
        End Try
        TraceMsg = System.Threading.Thread.CurrentThread.ManagedThreadId.ToString.PadLeft(2, "0"c) & " E)  " & TraceMsg
        Return rtnSize
    End Function