/// <summary>
/// When overridden in a derived class, reads a sequence of bytes from the current stream and advances the position within
/// the stream by the number of bytes read.
/// </summary>
/// <returns>
/// The total number of bytes read into the buffer. This can be less than the number of bytes requested if that many bytes
/// are not currently available, or zero (0) if the end of the stream has been reached.
/// </returns>
/// <param name="buffer">
/// An array of bytes. When this method returns, the buffer contains the specified byte array with the
/// values between <paramref name="offset" /> and (<paramref name="offset" /> + <paramref name="count" /> - 1) replaced by
/// the bytes read from the current source.
/// </param>
/// <param name="offset">
/// The zero-based byte offset in <paramref name="buffer" /> at which to begin storing the data read
/// from the current stream.
/// </param>
/// <param name="count">The maximum number of bytes to be read from the current stream. </param>
/// <exception cref="T:System.ArgumentException">
/// The sum of <paramref name="offset" /> and <paramref name="count" /> is
/// larger than the buffer length.
/// </exception>
/// <exception cref="T:System.ArgumentNullException"><paramref name="buffer" /> is null. </exception>
/// <exception cref="T:System.ArgumentOutOfRangeException">
/// <paramref name="offset" /> or <paramref name="count" /> is
/// negative.
/// </exception>
/// <exception cref="T:System.IO.IOException">An I/O error occurs. </exception>
/// <exception cref="T:System.NotSupportedException">The stream does not support reading. </exception>
/// <exception cref="T:System.ObjectDisposedException">Methods were called after the stream was closed. </exception>
public override int Read(byte[] buffer, int offset, int count)
{
buffer.ThrowIfInvalid("buffer", b => b != null, "Buffer cannot be null.");
offset.ThrowIfInvalid("offset", o => o >= 0, "Offset must be a value greater than or equal to zero.");
count.ThrowIfInvalid("count", c => c >= 0, "Count must be a value greater than or equal to zero.");
if (buffer.Length - offset < count)
{
throw new ArgumentException(
String.Format(
"Buffer length minus the offset must be greater than or equal to count (buffer.Length = {0}, offset = {1}, count = {2}).",
buffer.Length, offset, count));
}
if (this.endOfPayload)
{
return(0);
}
if (this.lineBuffer == null)
{
SeekPreamble(this.stream, out this.unixLineEnding);
this.lineBuffer = UUEncoder.DecodeLine(this.stream);
this.ReadLineEnding();
this.lineBufferIndex = 0;
}
int readCount = 0;
int remainingCount = count;
while (remainingCount > 0)
{
int lineBufferCount = this.lineBuffer.Length - this.lineBufferIndex;
if (remainingCount >= lineBufferCount)
{
Array.Copy(this.lineBuffer, this.lineBufferIndex, buffer, offset + readCount, lineBufferCount);
if (this.lineBuffer.Length == 0)
{
break;
}
this.lineBuffer = UUEncoder.DecodeLine(this.stream);
this.ReadLineEnding();
this.lineBufferIndex = 0;
readCount += lineBufferCount;
remainingCount -= lineBufferCount;
}
else
{
Array.Copy(this.lineBuffer, this.lineBufferIndex, buffer, offset + readCount, remainingCount);
this.lineBufferIndex += remainingCount;
readCount += remainingCount;
remainingCount = 0;
}
}
if (this.lineBuffer.Length == 0)
{
this.endOfPayload = true;
}
return(readCount);
}
private void FlushBuffer(byte[] buffer)
{
byte[] encodedBuffer = UUEncoder.EncodeLine(buffer);
this.stream.Write(encodedBuffer, 0, encodedBuffer.Length);
this.stream.Write(this.lineEnding, 0, this.lineEnding.Length);
}
