SIPSorcery.SIP.App.SIPClientUserAgent.Cancel C# (CSharp) Method

        public void Cancel()
        {
            try
            {
                m_callCancelled = true;

                // Cancel server call.
                if (m_serverTransaction == null)
                {
                    Log_External(new SIPMonitorConsoleEvent(SIPMonitorServerTypesEnum.UserAgentClient, SIPMonitorEventTypesEnum.DialPlan, "Cancelling forwarded call leg " + m_sipCallDescriptor.Uri + ", server transaction has not been created yet no CANCEL request required.", Owner));
                }
                else if (m_cancelTransaction != null)
                {
                    if (m_cancelTransaction.TransactionState != SIPTransactionStatesEnum.Completed)
                    {
                        Log_External(new SIPMonitorConsoleEvent(SIPMonitorServerTypesEnum.UserAgentClient, SIPMonitorEventTypesEnum.DialPlan, "Call " + m_serverTransaction.TransactionRequest.URI.ToString() + " has already been cancelled once, trying again.", Owner));
                        m_cancelTransaction.SendRequest(m_cancelTransaction.TransactionRequest);
                    }
                    else
                    {
                        Log_External(new SIPMonitorConsoleEvent(SIPMonitorServerTypesEnum.UserAgentClient, SIPMonitorEventTypesEnum.DialPlan, "Call " + m_serverTransaction.TransactionRequest.URI.ToString() + " has already responded to CANCEL, probably overlap in messages not re-sending.", Owner));
                    }
                }
                else //if (m_serverTransaction.TransactionState == SIPTransactionStatesEnum.Proceeding || m_serverTransaction.TransactionState == SIPTransactionStatesEnum.Trying)
                {
                    //logger.Debug("Cancelling forwarded call leg, sending CANCEL to " + ForwardedTransaction.TransactionRequest.URI.ToString() + " (transid: " + ForwardedTransaction.TransactionId + ").");
                    Log_External(new SIPMonitorConsoleEvent(SIPMonitorServerTypesEnum.UserAgentClient, SIPMonitorEventTypesEnum.DialPlan, "Cancelling forwarded call leg, sending CANCEL to " + m_serverTransaction.TransactionRequest.URI.ToString() + ".", Owner));

                    // No reponse has been received from the server so no CANCEL request neccessary, stop any retransmits of the INVITE.
                    m_serverTransaction.CancelCall();

                    SIPRequest cancelRequest = GetCancelRequest(m_serverTransaction.TransactionRequest);
                    m_cancelTransaction = m_sipTransport.CreateNonInviteTransaction(cancelRequest, m_serverEndPoint, m_serverTransaction.LocalSIPEndPoint, m_outboundProxy);
                    m_cancelTransaction.TransactionTraceMessage += TransactionTraceMessage;
                    //m_cancelTransaction.SendRequest(m_serverEndPoint, cancelRequest);
                    m_cancelTransaction.SendReliableRequest();
                }
                //else
                //{
                // No reponse has been received from the server so no CANCEL request neccessary, stop any retransmits of the INVITE.
                //    m_serverTransaction.CancelCall();
                //    Log_External(new SIPMonitorConsoleEvent(SIPMonitorServerTypesEnum.UserAgentClient, SIPMonitorEventTypesEnum.DialPlan, "Cancelling forwarded call leg " + m_sipCallDescriptor.Uri.ToString() + ", no response from server has been received so no CANCEL request required.", Owner));
                //}

                FireCallFailed(this, "Call cancelled by user.");
            }
            catch (Exception excp)
            {
                Log_External(new SIPMonitorConsoleEvent(SIPMonitorServerTypesEnum.UserAgentClient, SIPMonitorEventTypesEnum.DialPlan, "Exception CancelServerCall. " + excp.Message, Owner));
            }
        }

        public void Cancel()
        {
            logger.LogDebug("SIPB2BUserAgent Cancel.");
            m_uac.Cancel();

            var busyResp = SIPResponse.GetResponse(m_uasTransaction.TransactionRequest, SIPResponseStatusCodesEnum.BusyHere, null);

            m_uasTransaction.SendFinalResponse(busyResp);
        }