Esempio n. 1
0
        /// <summary>
        /// Spin wait until data is avaiable or timed out.
        /// </summary>
        /// <param name="source">The source stream to check.</param>
        /// <param name="timeoutClock">The time to check.</param>
        private static void SpinWaitHandler(System.IO.Stream source, Custom.TimeoutClock timeoutClock)
        {
            bool exitIndicator = false;

            // Create the tasks.
            Task[] tasks = new Task[1];

            // Poller task.
            Task poller = Task.Factory.StartNew(() =>
            {
                // Create a new spin wait.
                SpinWait sw = new SpinWait();

                // Action to perform.
                while (!exitIndicator)
                {
                    // The NextSpinWillYield property returns true if
                    // calling sw.SpinOnce() will result in yielding the
                    // processor instead of simply spinning.
                    if (sw.NextSpinWillYield)
                    {
                        if (timeoutClock.IsComplete() || source.Length > 0)
                        {
                            exitIndicator = true;
                        }
                    }
                    sw.SpinOnce();
                }
            });

            // Assign the listener task.
            tasks[0] = poller;

            // Wait for all tasks to complete.
            Task.WaitAll(tasks);

            // For each task.
            foreach (Task item in tasks)
            {
                try
                {
                    // Release the resources.
                    item.Dispose();
                }
                catch { }
            }
            tasks = null;
        }
Esempio n. 2
0
        /// <summary>
        /// Read the bytes from the stream.
        /// </summary>
        /// <param name="source">The current stream.</param>
        /// <param name="length">The number of bytes to read.</param>
        /// <param name="completed">True if completed and did not timeout; else false.</param>
        /// <param name="timeout">The maximum time in milliseconds to wait for the end of the header data; -1 wait indefinitely.</param>
        /// <returns>The bytes read.</returns>
        public static byte[] ReadBytesTimer(this System.IO.Stream source, int length, out bool completed, long timeout = -1)
        {
            int  readBytes      = 0;
            long totalBytesRead = 0;
            int  bufferLength   = length;

            byte[] buffer = new byte[bufferLength];

            // If completed.
            completed = true;

            using (MemoryStream destination = new MemoryStream())
            {
                // Only if data needs to be found.
                if (length > 0)
                {
                    // Start a new timeout clock.
                    Custom.TimeoutClock timeoutClock = new Custom.TimeoutClock((int)timeout);

                    // Read all the data in the source stream and
                    // write the data to the destination stream.
                    do
                    {
                        // Determine the number of bytes to read
                        // from the byteLength and buffer_size.
                        // Can not read more then byteLength.
                        if (length <= bufferLength)
                        {
                            // Look for current total bytes read and number left.
                            long left = length - totalBytesRead;
                            if (left <= bufferLength)
                            {
                                bufferLength = (int)left;
                            }
                            else
                            {
                                bufferLength = (int)length;
                            }
                        }
                        else
                        {
                            // Look for current total bytes read and number left.
                            long left = length - totalBytesRead;
                            if (left <= bufferLength)
                            {
                                bufferLength = (int)left;
                            }
                        }

                        // Read the data and then write the data.
                        readBytes = source.Read(buffer, 0, bufferLength);

                        // If data exists.
                        if (readBytes > 0)
                        {
                            // Each time data is read reset the timeout.
                            timeoutClock.Reset();
                            totalBytesRead += readBytes;
                            destination.Write(buffer, 0, readBytes);
                        }
                        else
                        {
                            SpinWaitHandler(source, timeoutClock);
                        }

                        // If the timeout has been reached then
                        // break from the loop.
                        if (timeoutClock.IsComplete())
                        {
                            completed = false;
                            break;
                        }
                    }while (totalBytesRead < length);
                }

                // Return the data as bytes.
                destination.Close();
                return(destination.ToArray());
            }
        }