C# Sockets.IPPacketInformation类代码示例

 private unsafe void InitIPPacketInformation()
 {
     IPAddress address = null;
     if (this.m_ControlBuffer.Length == s_ControlDataSize)
     {
         UnsafeNclNativeMethods.OSSOCK.ControlData data = (UnsafeNclNativeMethods.OSSOCK.ControlData) Marshal.PtrToStructure(this.m_Message.controlBuffer.Pointer, typeof(UnsafeNclNativeMethods.OSSOCK.ControlData));
         if (data.length != UIntPtr.Zero)
         {
             address = new IPAddress((long) data.address);
         }
         this.m_IPPacketInformation = new IPPacketInformation((address != null) ? address : IPAddress.None, (int) data.index);
     }
     else if (this.m_ControlBuffer.Length == s_ControlDataIPv6Size)
     {
         UnsafeNclNativeMethods.OSSOCK.ControlDataIPv6 pv = (UnsafeNclNativeMethods.OSSOCK.ControlDataIPv6) Marshal.PtrToStructure(this.m_Message.controlBuffer.Pointer, typeof(UnsafeNclNativeMethods.OSSOCK.ControlDataIPv6));
         if (pv.length != UIntPtr.Zero)
         {
             address = new IPAddress(pv.address);
         }
         this.m_IPPacketInformation = new IPPacketInformation((address != null) ? address : IPAddress.IPv6None, (int) pv.index);
     }
     else
     {
         this.m_IPPacketInformation = new IPPacketInformation();
     }
 }

        public void CompletionCallback(int numBytes, byte[] socketAddress, int socketAddressSize, SocketFlags receivedFlags, IPPacketInformation ipPacketInformation, SocketError errorCode)
        {
            Debug.Assert(_socketAddress != null);
            Debug.Assert(socketAddress == null || _socketAddress.Buffer == socketAddress);

            _socketAddressSize = socketAddressSize;
            _socketFlags = receivedFlags;
            _ipPacketInformation = ipPacketInformation;

            base.CompletionCallback(numBytes, errorCode);
        }

        public static NetworkInterface GetInterface(IPPacketInformation packetInfo)
        {
            int interfaceId = packetInfo.Interface;

            NetworkInterface[] interfaces = NetworkInterface.GetAllNetworkInterfaces();

            foreach (var netInterface in interfaces)
            {
                var ipv4InterfaceProps = netInterface.GetIPProperties().GetIPv4Properties();

                if (ipv4InterfaceProps != null &&
                    ipv4InterfaceProps.Index == interfaceId)
                    return netInterface;
            }

            return null;
        }

    public int ReceiveMessageFrom(byte[] buffer, int offset, int size, ref SocketFlags socketFlags, ref System.Net.EndPoint remoteEP, out IPPacketInformation ipPacketInformation)
    {
      ipPacketInformation = default(IPPacketInformation);

      return default(int);
    }

		public int ReceiveMessageFrom (byte[] buffer, int offset, int size, ref SocketFlags socketFlags, ref EndPoint remoteEP, out IPPacketInformation ipPacketInformation)
		{
			ThrowIfDisposedAndClosed ();
			ThrowIfBufferNull (buffer);
			ThrowIfBufferOutOfRange (buffer, offset, size);

			if (remoteEP == null)
				throw new ArgumentNullException ("remoteEP");

			// FIXME: figure out how we get hold of the IPPacketInformation
			throw new NotImplementedException ();
		}

        // Receives a datagram into a specific location in the data buffer and stores
        // the end point.
        public int ReceiveMessageFrom(byte[] buffer, int offset, int size, ref SocketFlags socketFlags, ref EndPoint remoteEP, out IPPacketInformation ipPacketInformation)
        {
            if (s_loggingEnabled)
            {
                Logging.Enter(Logging.Sockets, this, "ReceiveMessageFrom", "");
            }

            if (CleanedUp)
            {
                throw new ObjectDisposedException(this.GetType().FullName);
            }
            if (buffer == null)
            {
                throw new ArgumentNullException("buffer");
            }
            if (remoteEP == null)
            {
                throw new ArgumentNullException("remoteEP");
            }
            if (!CanTryAddressFamily(remoteEP.AddressFamily))
            {
                throw new ArgumentException(SR.Format(SR.net_InvalidEndPointAddressFamily, remoteEP.AddressFamily, _addressFamily), "remoteEP");
            }
            if (offset < 0 || offset > buffer.Length)
            {
                throw new ArgumentOutOfRangeException("offset");
            }
            if (size < 0 || size > buffer.Length - offset)
            {
                throw new ArgumentOutOfRangeException("size");
            }
            if (_rightEndPoint == null)
            {
                throw new InvalidOperationException(SR.net_sockets_mustbind);
            }

            ValidateBlockingMode();

            // We don't do a CAS demand here because the contents of remoteEP aren't used by
            // WSARecvMsg; all that matters is that we generate a unique-to-this-call SocketAddress
            // with the right address family.
            EndPoint endPointSnapshot = remoteEP;
            Internals.SocketAddress socketAddress = SnapshotAndSerialize(ref endPointSnapshot);

            // Save a copy of the original EndPoint.
            Internals.SocketAddress socketAddressOriginal = IPEndPointExtensions.Serialize(endPointSnapshot);

            SetReceivingPacketInformation();

            Internals.SocketAddress receiveAddress;
            int bytesTransferred;
            SocketError errorCode = SocketPal.ReceiveMessageFrom(this, _handle, buffer, offset, size, ref socketFlags, socketAddress, out receiveAddress, out ipPacketInformation, out bytesTransferred);

            // Throw an appropriate SocketException if the native call fails.
            if (errorCode != SocketError.Success && errorCode != SocketError.MessageSize)
            {
                // Update the internal state of this socket according to the error before throwing.
                SocketException socketException = new SocketException((int)errorCode);
                UpdateStatusAfterSocketError(socketException);
                if (s_loggingEnabled)
                {
                    Logging.Exception(Logging.Sockets, this, "ReceiveMessageFrom", socketException);
                }
                throw socketException;
            }

            if (!socketAddressOriginal.Equals(receiveAddress))
            {
                try
                {
                    remoteEP = endPointSnapshot.Create(receiveAddress);
                }
                catch
                {
                }
                if (_rightEndPoint == null)
                {
                    // Save a copy of the EndPoint so we can use it for Create().
                    _rightEndPoint = endPointSnapshot;
                }
            }

            if (s_loggingEnabled)
            {
                Logging.Exit(Logging.Sockets, this, "ReceiveMessageFrom", errorCode);
            }
            return bytesTransferred;
        }

		public int EndReceiveMessageFrom (IAsyncResult asyncResult,
						  ref SocketFlags socketFlags,
						  ref EndPoint endPoint,
						  out IPPacketInformation ipPacketInformation)
		{
			if (disposed && closed)
				throw new ObjectDisposedException (GetType ().ToString ());

			if (asyncResult == null)
				throw new ArgumentNullException ("asyncResult");

			if (endPoint == null)
				throw new ArgumentNullException ("endPoint");

			SocketAsyncResult req = asyncResult as SocketAsyncResult;
			if (req == null)
				throw new ArgumentException ("Invalid IAsyncResult", "asyncResult");

			if (Interlocked.CompareExchange (ref req.EndCalled, 1, 0) == 1)
				throw InvalidAsyncOp ("EndReceiveMessageFrom");
			throw new NotImplementedException ();
		}

        public static SocketError ReceiveMessageFrom(Socket socket, SafeCloseSocket handle, byte[] buffer, int offset, int count, ref SocketFlags socketFlags, Internals.SocketAddress socketAddress, out Internals.SocketAddress receiveAddress, out IPPacketInformation ipPacketInformation, out int bytesTransferred)
        {
            byte[] socketAddressBuffer = socketAddress.Buffer;
            int socketAddressLen = socketAddress.Size;

            bool isIPv4, isIPv6;
            Socket.GetIPProtocolInformation(socket.AddressFamily, socketAddress, out isIPv4, out isIPv6);

            SocketError errorCode;
            if (!handle.IsNonBlocking)
            {
                errorCode = handle.AsyncContext.ReceiveMessageFrom(buffer, offset, count, ref socketFlags, socketAddressBuffer, ref socketAddressLen, isIPv4, isIPv6, handle.ReceiveTimeout, out ipPacketInformation, out bytesTransferred);
            }
            else
            {
                if (!TryCompleteReceiveMessageFrom(handle.FileDescriptor, buffer, offset, count, socketFlags, socketAddressBuffer, ref socketAddressLen, isIPv4, isIPv6, out bytesTransferred, out socketFlags, out ipPacketInformation, out errorCode))
                {
                    errorCode = SocketError.WouldBlock;
                }
            }

            socketAddress.InternalSize = socketAddressLen;
            receiveAddress = socketAddress;
            return errorCode;
        }

//.........这里部分代码省略.........
                    }
                    break;

                case SocketAsyncOperation.ReceiveMessageFrom:

                    if (bytesTransferred > 0) {
                        // Log and Perf counters.
                        if (s_LoggingEnabled) LogBuffer(bytesTransferred);
                        if (Socket.s_PerfCountersEnabled) UpdatePerfCounters(bytesTransferred, false);
                    }

                    // Deal with incoming address.
                    m_SocketAddress.SetSize(m_PtrSocketAddressBufferSize);
                    socketAddressOriginal = m_RemoteEndPoint.Serialize();
                    if(!socketAddressOriginal.Equals(m_SocketAddress)) {
                        try {
                            m_RemoteEndPoint = m_RemoteEndPoint.Create(m_SocketAddress);
                        }
                        catch {
                        }
                    }

                    // Extract the packet information.
                    unsafe {
                        IPAddress address = null;
                        UnsafeNclNativeMethods.OSSOCK.WSAMsg* PtrMessage = (UnsafeNclNativeMethods.OSSOCK.WSAMsg*)Marshal.UnsafeAddrOfPinnedArrayElement(m_WSAMessageBuffer, 0);

                        //ipv4
                        if(m_ControlBuffer.Length == s_ControlDataSize) {
                            UnsafeNclNativeMethods.OSSOCK.ControlData controlData = (UnsafeNclNativeMethods.OSSOCK.ControlData)Marshal.PtrToStructure(PtrMessage->controlBuffer.Pointer, typeof(UnsafeNclNativeMethods.OSSOCK.ControlData));
                            if(controlData.length != UIntPtr.Zero) {
                                address = new IPAddress((long)controlData.address);
                            }
                            m_ReceiveMessageFromPacketInfo = new IPPacketInformation(((address != null) ? address : IPAddress.None), (int)controlData.index);
                        }
                            //ipv6
                        else if(m_ControlBuffer.Length == s_ControlDataIPv6Size) {
                            UnsafeNclNativeMethods.OSSOCK.ControlDataIPv6 controlData = (UnsafeNclNativeMethods.OSSOCK.ControlDataIPv6)Marshal.PtrToStructure(PtrMessage->controlBuffer.Pointer, typeof(UnsafeNclNativeMethods.OSSOCK.ControlDataIPv6));
                            if(controlData.length != UIntPtr.Zero) {
                                address = new IPAddress(controlData.address);
                            }
                            m_ReceiveMessageFromPacketInfo = new IPPacketInformation(((address != null) ? address : IPAddress.IPv6None), (int)controlData.index);
                        }
                            //other
                        else {
                            m_ReceiveMessageFromPacketInfo = new IPPacketInformation();
                        }
                    }
                    break;

                case SocketAsyncOperation.Send:

                    if (bytesTransferred > 0) {
                        // Log and Perf counters.
                        if (s_LoggingEnabled) LogBuffer(bytesTransferred);
                        if (Socket.s_PerfCountersEnabled) UpdatePerfCounters(bytesTransferred, true);
                    }
                    break;

                case SocketAsyncOperation.SendPackets:

                    if(bytesTransferred > 0) {
                        // Log and Perf counters.
                        if(s_LoggingEnabled) LogSendPacketsBuffers(bytesTransferred);
                        if(Socket.s_PerfCountersEnabled) UpdatePerfCounters(bytesTransferred, true);
                    }

 /// <summary>
 /// Receives the specified number of bytes of data into the specified location of the data buffer, using the specified <see cref="T:System.Net.Sockets.SocketFlags"/>, and stores the endpoint and packet information.
 /// </summary>
 /// 
 /// <returns>
 /// The number of bytes received.
 /// </returns>
 /// <param name="buffer">An array of type <see cref="T:System.Byte"/> that is the storage location for received data.</param><param name="offset">The position in the <paramref name="buffer"/> parameter to store the received data.</param><param name="size">The number of bytes to receive.</param><param name="socketFlags">A bitwise combination of the <see cref="T:System.Net.Sockets.SocketFlags"/> values.</param><param name="remoteEP">An <see cref="T:System.Net.EndPoint"/>, passed by reference, that represents the remote server.</param><param name="ipPacketInformation">An <see cref="T:System.Net.Sockets.IPPacketInformation"/> holding address and interface information.</param><exception cref="T:System.ArgumentNullException"><paramref name="buffer"/> is null.- or- <paramref name="remoteEP"/> is null. </exception><exception cref="T:System.ArgumentOutOfRangeException"><paramref name="offset"/> is less than 0.-or- <paramref name="offset"/> is greater than the length of <paramref name="buffer"/>.-or- <paramref name="size"/> is less than 0.-or- <paramref name="size"/> is greater than the length of the <paramref name="buffer"/> minus the value of the offset parameter. </exception><exception cref="T:System.Net.Sockets.SocketException"><paramref name="socketFlags"/> is not a valid combination of values.-or- The <see cref="P:System.Net.Sockets.Socket.LocalEndPoint"/> property was not set.-or- The .NET Framework is running on an AMD 64-bit processor.-or- An error occurred when attempting to access the socket. See the Remarks section for more information. </exception><exception cref="T:System.ObjectDisposedException">The <see cref="T:System.Net.Sockets.Socket"/> has been closed. </exception><exception cref="T:System.NotSupportedException">The operating system is Windows 2000 or earlier, and this method requires Windows XP.</exception>
 public int ReceiveMessageFrom(byte[] buffer, int offset, int size, ref SocketFlags socketFlags, ref EndPoint remoteEP, out IPPacketInformation ipPacketInformation)
 {
     if (Socket.s_LoggingEnabled)
     Logging.Enter(Logging.Sockets, (object) this, "ReceiveMessageFrom", "");
       if (this.CleanedUp)
     throw new ObjectDisposedException(this.GetType().FullName);
       if (buffer == null)
     throw new ArgumentNullException("buffer");
       if (remoteEP == null)
     throw new ArgumentNullException("remoteEP");
       if (!this.CanTryAddressFamily(remoteEP.AddressFamily))
       {
     throw new ArgumentException(SR.GetString("net_InvalidEndPointAddressFamily", (object) remoteEP.AddressFamily, (object) this.addressFamily), "remoteEP");
       }
       else
       {
     if (offset < 0 || offset > buffer.Length)
       throw new ArgumentOutOfRangeException("offset");
     if (size < 0 || size > buffer.Length - offset)
       throw new ArgumentOutOfRangeException("size");
     if (this.m_RightEndPoint == null)
       throw new InvalidOperationException(SR.GetString("net_sockets_mustbind"));
     this.ValidateBlockingMode();
     EndPoint remoteEP1 = remoteEP;
     SocketAddress socketAddress1 = this.SnapshotAndSerialize(ref remoteEP1);
     ReceiveMessageOverlappedAsyncResult overlappedAsyncResult = new ReceiveMessageOverlappedAsyncResult(this, (object) null, (AsyncCallback) null);
     overlappedAsyncResult.SetUnmanagedStructures(buffer, offset, size, socketAddress1, socketFlags);
     SocketAddress socketAddress2 = remoteEP1.Serialize();
     int bytesTransferred = 0;
     SocketError socketError = SocketError.Success;
     this.SetReceivingPacketInformation();
     try
     {
       if (this.WSARecvMsg_Blocking(this.m_Handle.DangerousGetHandle(), Marshal.UnsafeAddrOfPinnedArrayElement((Array) overlappedAsyncResult.m_MessageBuffer, 0), out bytesTransferred, IntPtr.Zero, IntPtr.Zero) == SocketError.SocketError)
     socketError = (SocketError) Marshal.GetLastWin32Error();
     }
     finally
     {
       overlappedAsyncResult.SyncReleaseUnmanagedStructures();
     }
     if (socketError != SocketError.Success && socketError != SocketError.MessageSize)
     {
       SocketException socketException = new SocketException(socketError);
       this.UpdateStatusAfterSocketError(socketException);
       if (Socket.s_LoggingEnabled)
     Logging.Exception(Logging.Sockets, (object) this, "ReceiveMessageFrom", (Exception) socketException);
       throw socketException;
     }
     else
     {
       if (!socketAddress2.Equals((object) overlappedAsyncResult.m_SocketAddress))
       {
     try
     {
       remoteEP = remoteEP1.Create(overlappedAsyncResult.m_SocketAddress);
     }
     catch
     {
     }
     if (this.m_RightEndPoint == null)
       this.m_RightEndPoint = remoteEP1;
       }
       socketFlags = overlappedAsyncResult.m_flags;
       ipPacketInformation = overlappedAsyncResult.m_IPPacketInformation;
       if (Socket.s_LoggingEnabled)
     Logging.Exit(Logging.Sockets, (object) this, "ReceiveMessageFrom", (object) socketError);
       return bytesTransferred;
     }
       }
 }

 /// <summary>
 /// Ends a pending asynchronous read from a specific endpoint. This method also reveals more information about the packet than <see cref="M:System.Net.Sockets.Socket.EndReceiveFrom(System.IAsyncResult,[email protected])"/>.
 /// </summary>
 /// 
 /// <returns>
 /// If successful, the number of bytes received. If unsuccessful, returns 0.
 /// </returns>
 /// <param name="asyncResult">An <see cref="T:System.IAsyncResult"/> that stores state information and any user defined data for this asynchronous operation.</param><param name="socketFlags">A bitwise combination of the <see cref="T:System.Net.Sockets.SocketFlags"/> values for the received packet.</param><param name="endPoint">The source <see cref="T:System.Net.EndPoint"/>.</param><param name="ipPacketInformation">The <see cref="T:System.Net.IPAddress"/> and interface of the received packet.</param><exception cref="T:System.ArgumentNullException"><paramref name="asyncResult"/> is null-or- <paramref name="endPoint"/> is null. </exception><exception cref="T:System.ArgumentException"><paramref name="asyncResult"/> was not returned by a call to the <see cref="M:System.Net.Sockets.Socket.BeginReceiveMessageFrom(System.Byte[],System.Int32,System.Int32,System.Net.Sockets.SocketFlags,[email protected],System.AsyncCallback,System.Object)"/> method. </exception><exception cref="T:System.InvalidOperationException"><see cref="M:System.Net.Sockets.Socket.EndReceiveMessageFrom(System.IAsyncResult,[email protected],[email protected],[email protected])"/> was previously called for the asynchronous read. </exception><exception cref="T:System.Net.Sockets.SocketException">An error occurred when attempting to access the socket. See the Remarks section for more information. </exception><exception cref="T:System.ObjectDisposedException">The <see cref="T:System.Net.Sockets.Socket"/> has been closed. </exception>
 public int EndReceiveMessageFrom(IAsyncResult asyncResult, ref SocketFlags socketFlags, ref EndPoint endPoint, out IPPacketInformation ipPacketInformation)
 {
     if (Socket.s_LoggingEnabled)
     Logging.Enter(Logging.Sockets, (object) this, "EndReceiveMessageFrom", (object) asyncResult);
       if (this.CleanedUp)
     throw new ObjectDisposedException(this.GetType().FullName);
       if (endPoint == null)
     throw new ArgumentNullException("endPoint");
       if (!this.CanTryAddressFamily(endPoint.AddressFamily))
       {
     throw new ArgumentException(SR.GetString("net_InvalidEndPointAddressFamily", (object) endPoint.AddressFamily, (object) this.addressFamily), "endPoint");
       }
       else
       {
     if (asyncResult == null)
       throw new ArgumentNullException("asyncResult");
     ReceiveMessageOverlappedAsyncResult overlappedAsyncResult = asyncResult as ReceiveMessageOverlappedAsyncResult;
     if (overlappedAsyncResult == null || overlappedAsyncResult.AsyncObject != this)
       throw new ArgumentException(SR.GetString("net_io_invalidasyncresult"), "asyncResult");
     if (overlappedAsyncResult.EndCalled)
     {
       throw new InvalidOperationException(SR.GetString("net_io_invalidendcall", new object[1]
       {
     (object) "EndReceiveMessageFrom"
       }));
     }
     else
     {
       SocketAddress socketAddress = this.SnapshotAndSerialize(ref endPoint);
       int num = (int) overlappedAsyncResult.InternalWaitForCompletion();
       overlappedAsyncResult.EndCalled = true;
       overlappedAsyncResult.ExtractCache(ref this.Caches.ReceiveOverlappedCache);
       overlappedAsyncResult.SocketAddress.SetSize(overlappedAsyncResult.GetSocketAddressSizePtr());
       if (!socketAddress.Equals((object) overlappedAsyncResult.SocketAddress))
       {
     try
     {
       endPoint = endPoint.Create(overlappedAsyncResult.SocketAddress);
     }
     catch
     {
     }
       }
       if (Socket.s_PerfCountersEnabled && num > 0)
       {
     NetworkingPerfCounters.Instance.Increment(NetworkingPerfCounterName.SocketBytesReceived, (long) num);
     if (this.Transport == TransportType.Udp)
       NetworkingPerfCounters.Instance.Increment(NetworkingPerfCounterName.SocketDatagramsReceived);
       }
       if (overlappedAsyncResult.ErrorCode != 0 && overlappedAsyncResult.ErrorCode != 10040)
       {
     SocketException socketException = new SocketException(overlappedAsyncResult.ErrorCode);
     this.UpdateStatusAfterSocketError(socketException);
     if (Socket.s_LoggingEnabled)
       Logging.Exception(Logging.Sockets, (object) this, "EndReceiveMessageFrom", (Exception) socketException);
     throw socketException;
       }
       else
       {
     socketFlags = overlappedAsyncResult.m_flags;
     ipPacketInformation = overlappedAsyncResult.m_IPPacketInformation;
     if (Socket.s_LoggingEnabled)
       Logging.Exit(Logging.Sockets, (object) this, "EndReceiveMessageFrom", (object) num);
     return num;
       }
     }
       }
 }

        /// <devdoc>
        ///    <para>Receives a datagram into a specific location in the data buffer and stores
        ///       the end point.</para>
        /// </devdoc>
        public int ReceiveMessageFrom(byte[] buffer, int offset, int size, ref SocketFlags socketFlags, ref EndPoint remoteEP, out IPPacketInformation ipPacketInformation)
        {
            if(Logging.On)Logging.Enter(Logging.Sockets, this, "ReceiveMessageFrom", "");

            if (CleanedUp) {
                throw new ObjectDisposedException(this.GetType().FullName);
            }
            if (buffer==null) {
                throw new ArgumentNullException("buffer");
            }
            if (remoteEP==null) {
                throw new ArgumentNullException("remoteEP");
            }
            if (offset<0 || offset>buffer.Length) {
                throw new ArgumentOutOfRangeException("offset");
            }
            if (size<0 || size>buffer.Length-offset) {
                throw new ArgumentOutOfRangeException("size");
            }
            if (m_RightEndPoint==null) {
                throw new InvalidOperationException(SR.GetString(SR.net_sockets_mustbind));
            }

            ValidateBlockingMode();

            // This will check the permissions for connect.
            EndPoint endPointSnapshot = remoteEP;
            SocketAddress socketAddress = CheckCacheRemote(ref endPointSnapshot, false);

            ReceiveMessageOverlappedAsyncResult asyncResult = new ReceiveMessageOverlappedAsyncResult(this,null,null);
            asyncResult.SetUnmanagedStructures(buffer, offset, size, socketAddress, socketFlags);

            // save a copy of the original EndPoint
            SocketAddress socketAddressOriginal = endPointSnapshot.Serialize();

            //setup structure
            int bytesTransfered = 0;
            SocketError errorCode = SocketError.Success;

            if(addressFamily == AddressFamily.InterNetwork) {
                SetSocketOption(SocketOptionLevel.IP,SocketOptionName.PacketInformation,true);
            }
            else if (addressFamily == AddressFamily.InterNetworkV6){
                SetSocketOption(SocketOptionLevel.IPv6,SocketOptionName.PacketInformation,true);
            }

            try
            {
                // This can throw ObjectDisposedException (retrieving the delegate AND resolving the handle).
                if (WSARecvMsg_Blocking(
                    m_Handle.DangerousGetHandle(),
                    Marshal.UnsafeAddrOfPinnedArrayElement(asyncResult.m_MessageBuffer,0),
                    out bytesTransfered,
                    IntPtr.Zero,
                    IntPtr.Zero) == SocketError.SocketError)
                {
                    errorCode =  (SocketError)Marshal.GetLastWin32Error();
                }
            }
            finally {
                asyncResult.SyncReleaseUnmanagedStructures();
            }

            //
            // if the native call fails we'll throw a SocketException
            //
            if (errorCode!=SocketError.Success && errorCode != SocketError.MessageSize) {
                //
                // update our internal state after this socket error and throw
                //
                SocketException socketException = new SocketException(errorCode);
                UpdateStatusAfterSocketError(socketException);
                if(Logging.On)Logging.Exception(Logging.Sockets, this, "ReceiveMessageFrom", socketException);
                throw socketException;
            }

            if (!socketAddressOriginal.Equals(asyncResult.m_SocketAddress))
            {
                try {
                    remoteEP = endPointSnapshot.Create(asyncResult.m_SocketAddress);
                }
                catch {
                }
                if (m_RightEndPoint==null) {
                    //
                    // save a copy of the EndPoint so we can use it for Create()
                    //
                    m_RightEndPoint = endPointSnapshot;
                }
            }

            socketFlags = asyncResult.m_flags;
            ipPacketInformation = asyncResult.m_IPPacketInformation;

            if(Logging.On)Logging.Exit(Logging.Sockets, this, "ReceiveMessageFrom", errorCode);
            return bytesTransfered;
//.........这里部分代码省略.........

        public int EndReceiveMessageFrom(IAsyncResult asyncResult, ref SocketFlags socketFlags, ref EndPoint endPoint, out IPPacketInformation ipPacketInformation)
        {
            if(Logging.On)Logging.Enter(Logging.Sockets, this, "EndReceiveMessageFrom", asyncResult);
            if (CleanedUp) {
                throw new ObjectDisposedException(this.GetType().FullName);
            }
            if (endPoint==null) {
                throw new ArgumentNullException("endPoint");
            }
            if (asyncResult==null) {
                throw new ArgumentNullException("asyncResult");
            }
            ReceiveMessageOverlappedAsyncResult castedAsyncResult = asyncResult as ReceiveMessageOverlappedAsyncResult;
            if (castedAsyncResult==null || castedAsyncResult.AsyncObject!=this) {
                throw new ArgumentException(SR.GetString(SR.net_io_invalidasyncresult), "asyncResult");
            }
            if (castedAsyncResult.EndCalled) {
                throw new InvalidOperationException(SR.GetString(SR.net_io_invalidendcall, "EndReceiveMessageFrom"));
            }

            int bytesTransferred = (int)castedAsyncResult.InternalWaitForCompletion();
            castedAsyncResult.EndCalled = true;
            castedAsyncResult.ExtractCache(ref Caches.ReceiveOverlappedCache);

            // Update socket address size
            castedAsyncResult.SocketAddress.SetSize(castedAsyncResult.GetSocketAddressSizePtr());

            // pick up the saved copy of the original EndPoint from the asyncResult
            SocketAddress socketAddressOriginal = endPoint.Serialize();

            if (!socketAddressOriginal.Equals(castedAsyncResult.SocketAddress)) {
                try {
                    endPoint = endPoint.Create(castedAsyncResult.SocketAddress);
                }
                catch {
                }
            }

            GlobalLog.Print("Socket#" + ValidationHelper.HashString(this) + "::EndReceiveMessageFrom() bytesTransferred:" + bytesTransferred.ToString());

            //
            // if the asynchronous native call failed asynchronously
            // we'll throw a SocketException
            //
            if ((SocketError)castedAsyncResult.ErrorCode!=SocketError.Success && (SocketError)castedAsyncResult.ErrorCode != SocketError.MessageSize) {
                //
                // update our internal state after this socket error and throw
                //
                SocketException socketException = new SocketException(castedAsyncResult.ErrorCode);
                UpdateStatusAfterSocketError(socketException);
                if(Logging.On)Logging.Exception(Logging.Sockets, this, "EndReceiveMessageFrom", socketException);
                throw socketException;
            }

            socketFlags = castedAsyncResult.m_flags;
            ipPacketInformation = castedAsyncResult.m_IPPacketInformation;

            if(Logging.On)Logging.Exit(Logging.Sockets, this, "EndReceiveMessageFrom", bytesTransferred);
            return bytesTransferred;
        }

        /// <summary>
        /// Extends ReceiveMessageFrom so that buffer offset of 0 and call to Array.Length are not needed.
        /// <example>
        /// socket.ReceiveMessageFrom(buffer, socketFlags, remoteEP, ipPacketInformation);
        /// </example>
        /// </summary>
        public static Int32 ReceiveMessageFrom(this Socket socket, Byte[] buffer, ref SocketFlags socketFlags, ref System.Net.EndPoint remoteEP, out IPPacketInformation ipPacketInformation)
        {
            if(socket == null) throw new ArgumentNullException("socket");

            if(buffer == null) throw new ArgumentNullException("buffer");

            return socket.ReceiveMessageFrom(buffer, 0, buffer.Length, ref socketFlags, ref remoteEP, out ipPacketInformation);
        }

        /// <devdoc>
        ///    <para>Receives a datagram into a specific location in the data buffer and stores
        ///       the end point.</para>
        /// </devdoc>
        public int ReceiveMessageFrom(byte[] buffer, int offset, int size, ref SocketFlags socketFlags, ref EndPoint remoteEP, out IPPacketInformation ipPacketInformation) {
            if(s_LoggingEnabled)Logging.Enter(Logging.Sockets, this, "ReceiveMessageFrom", "");

            if (CleanedUp) {
                throw new ObjectDisposedException(this.GetType().FullName);
            }
            if (buffer==null) {
                throw new ArgumentNullException("buffer");
            }
            if (remoteEP==null) {
                throw new ArgumentNullException("remoteEP");
            }
            if (!CanTryAddressFamily(remoteEP.AddressFamily)) {
                throw new ArgumentException(SR.GetString(SR.net_InvalidEndPointAddressFamily, 
                    remoteEP.AddressFamily, addressFamily), "remoteEP");
            }
            if (offset<0 || offset>buffer.Length) {
                throw new ArgumentOutOfRangeException("offset");
            }
            if (size<0 || size>buffer.Length-offset) {
                throw new ArgumentOutOfRangeException("size");
            }
            if (m_RightEndPoint==null) {
                throw new InvalidOperationException(SR.GetString(SR.net_sockets_mustbind));
            }


            ValidateBlockingMode();

            // We don't do a CAS demand here because the contents of remoteEP aren't used by
            // WSARecvMsg; all that matters is that we generate a unique-to-this-call SocketAddress
            // with the right address family
            EndPoint endPointSnapshot = remoteEP;
            SocketAddress socketAddress = SnapshotAndSerialize(ref endPointSnapshot);

            ReceiveMessageOverlappedAsyncResult asyncResult = new ReceiveMessageOverlappedAsyncResult(this,null,null);
            asyncResult.SetUnmanagedStructures(buffer, offset, size, socketAddress, socketFlags);

            // save a copy of the original EndPoint
            SocketAddress socketAddressOriginal = endPointSnapshot.Serialize();

            //setup structure
            int bytesTransfered = 0;
            SocketError errorCode = SocketError.Success;

            SetReceivingPacketInformation();

            try
            {
                // This can throw ObjectDisposedException (retrieving the delegate AND resolving the handle).
                if (WSARecvMsg_Blocking(
                    m_Handle.DangerousGetHandle(),
                    Marshal.UnsafeAddrOfPinnedArrayElement(asyncResult.m_MessageBuffer,0),
                    out bytesTransfered,
                    IntPtr.Zero,
                    IntPtr.Zero) == SocketError.SocketError)
                {
                    errorCode =  (SocketError)Marshal.GetLastWin32Error();
                }
            }
            finally {
                asyncResult.SyncReleaseUnmanagedStructures();
            }


            //
            // if the native call fails we'll throw a SocketException
            //
            if (errorCode!=SocketError.Success && errorCode != SocketError.MessageSize) {
                //
                // update our internal state after this socket error and throw
                //
                SocketException socketException = new SocketException(errorCode);
                UpdateStatusAfterSocketError(socketException);
                if(s_LoggingEnabled)Logging.Exception(Logging.Sockets, this, "ReceiveMessageFrom", socketException);
                throw socketException;
            }


            if (!socketAddressOriginal.Equals(asyncResult.m_SocketAddress))
            {
                try {
                    remoteEP = endPointSnapshot.Create(asyncResult.m_SocketAddress);
                }
                catch {
                }
                if (m_RightEndPoint==null) {
                    //
                    // save a copy of the EndPoint so we can use it for Create()
                    //
                    m_RightEndPoint = endPointSnapshot;
                }
            }

            socketFlags = asyncResult.m_flags;
            ipPacketInformation = asyncResult.m_IPPacketInformation;
//.........这里部分代码省略.........