/// <summary> /// Adds a header to the message, <b>prepending</b> the value before /// any existing values if the header already exists. /// </summary> /// <param name="name">The header name.</param> /// <param name="value">The new value.</param> public void PrependHeader(string name, SipValue value) { if (value == null) { throw new ArgumentNullException("value"); } headers.Prepend(name, value.ToString()); }
/// <summary> /// Attempts to return the client side transaction ID from the message. This is /// the <b>branch</b> parameter from the top-most <b>Via</b> header. /// </summary> /// <param name="transactionID">Returns as the transaction ID on success.</param> /// <returns><b><c>true</c> if the transaction ID was returned.</b></returns> public bool TryGetTransactionID(out string transactionID) { SipHeader via; SipValue viaValue; transactionID = null; via = base.Headers[SipHeader.Via]; if (via == null) { return(false); } viaValue = new SipValue(via.Text); return(viaValue.Parameters.TryGetValue("branch", out transactionID)); }
/// <summary> /// Initiates an asynchronous SIP request transaction. /// </summary> /// <param name="request">The <see cref="SipRequest" /> to be submitted.</param> /// <param name="dialog">The <see cref="SipDialog" /> for requests that initiate a dialog (or <c>null</c>).</param> /// <param name="callback">The delegate to be called when the operation completes (or <c>null</c>).</param> /// <param name="state">Application defined state (or <c>null</c>).</param> /// <returns>The <see cref="IAsyncResult" /> to be used to track the operation's progress.</returns> /// <remarks> /// <para> /// All requests to <see cref="BeginRequest(SipRequest,SipDialog,AsyncCallback,object)" /> must be matched with a /// call to <see cref="EndRequest" />. /// </para> /// <note> /// This method adds reasonable <b>Call-ID</b> and <b>CSeq</b> headers to the request if these /// headers are not already present. /// </note> /// </remarks> public IAsyncResult BeginRequest(SipRequest request, SipDialog dialog, AsyncCallback callback, object state) { ClientAsyncResult arClient = new ClientAsyncResult(request, dialog, callback, state); SipValue viaValue; SipCSeqValue vCSeq; string transactionID; SipClientTransaction transaction; ISipTransport transport; NetworkBinding remoteEP; if (dialog != null && request.Method != SipMethod.Invite) { throw new InvalidOperationException("Dialogs may be created only for INVITE requests."); } arClient.Dialog = dialog; transport = router.SelectTransport(this, request, out remoteEP); if (transport == null) { throw new SipException("No approriate transport is available."); } // Initialize the request's Via header and transaction ID as necessary. transactionID = SipHelper.GenerateBranchID(); viaValue = new SipValue(string.Format("SIP/2.0/{0} {1}", transport.Name, transport.Settings.ExternalBinding.Address)); viaValue["branch"] = transactionID; viaValue["rport"] = string.Empty; request.PrependHeader(SipHeader.Via, viaValue); // Initialize common headers as necessary if (!request.ContainsHeader(SipHeader.CallID)) { request.AddHeader(SipHeader.CallID, SipHelper.GenerateCallID()); } vCSeq = request.GetHeader <SipCSeqValue>(SipHeader.CSeq); if (vCSeq == null) { vCSeq = new SipCSeqValue(SipHelper.GenCSeq(), request.MethodText); request.AddHeader(SipHeader.CSeq, vCSeq); } // Initialize the transaction transaction = new SipClientTransaction(this, request, transactionID, transport, remoteEP); transaction.AgentState = arClient; // Handle initial dialog INVITE specific initialization if (dialog != null && request.Method == SipMethod.Invite && dialog.State == SipDialogState.Waiting) { // Client-side dialogs need to know the transaction so // they'll be able to send the confirming ACK. dialog.InitiatingTransaction = transaction; // Dialogs need to know about the sequence number used in INVITE requests so // that the ACK can be generated with the same sequence number. dialog.AckCSeq = vCSeq.Number; // The dialog has been intialized enough to be added to the core's // early dialog table. core.AddEarlyDialog(dialog); } // Start the transaction using (TimedLock.Lock(this)) { transactions.Add(transactionID, transaction); } transaction.Start(); arClient.Started(); return(arClient); }