/// <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;
}
/// <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());
}
}
