/// <summary>
/// Reads a byte from the stream and advances the position within the stream by one byte,
/// or returns -1 if at the end of the stream.
/// </summary>
///
/// <returns>
/// The unsigned byte cast to an <see cref="int"/>, or -1 if at the end of the stream.
/// </returns>
///
/// <exception cref="NotSupportedException">
/// If the stream does not support reading.
/// </exception>
///
/// <exception cref="ObjectDisposedException">
/// Methods were called after the stream was closed.
/// </exception>
///
/// <exception cref="HealthServiceException">
/// If there was a failure reading the data from HealthVault.
/// </exception>
///
public override int ReadByte()
{
if (!CanRead)
{
throw new NotSupportedException();
}
if (_disposed)
{
throw new ObjectDisposedException(nameof(BlobStream));
}
int result = -1;
// Check to see if there is still something in the buffer
if (_bufferList.Count > 0)
{
BufferRequest buffer = _bufferList[0];
result = buffer.Buffer[buffer.Offset];
buffer.Count--;
buffer.Offset++;
if (buffer.Count == 0)
{
_bufferList.RemoveAt(0);
}
}
else
{
// Get a new chunk
int bufferSize = (int)(_length ?? DefaultStreamBufferSize);
byte[] newBuffer = new byte[bufferSize];
int count = Read(newBuffer, 0, bufferSize);
if (count > 0)
{
result = newBuffer[0];
// Note, this makes a copy of the buffer.
_bufferList.Add(
new BufferRequest(newBuffer, 1, count - 1));
}
}
return(result);
}
private async Task WriteChunkAsync(int chunkSizeToWrite, bool uploadComplete)
{
int bytesInWebRequest = 0;
long start = 0;
byte[] webRequestBuffer = null;
if (chunkSizeToWrite > 0)
{
int writeBufferOffset = 0;
while (writeBufferOffset < chunkSizeToWrite)
{
BufferRequest curRequestBuffer = _bufferList[_currentBufferRequestIndex];
// Get the number of bytes in the current request buffer up to a chunk.
int numBytesToCopy = Math.Min(curRequestBuffer.Count, chunkSizeToWrite);
// Ensure we don't write past the end of the chunk buffer.
numBytesToCopy = Math.Min(
numBytesToCopy,
_chunkBuffer.Length - writeBufferOffset);
// Copy the bytes to be sent over in to the chunk buffer;
Array.Copy(
curRequestBuffer.Buffer,
curRequestBuffer.Offset,
_chunkBuffer,
writeBufferOffset,
numBytesToCopy);
writeBufferOffset += numBytesToCopy;
curRequestBuffer.Offset += numBytesToCopy;
curRequestBuffer.Count -= numBytesToCopy;
if (curRequestBuffer.Count < 1)
{
_currentBufferRequestIndex++;
}
}
if (_currentBufferRequestIndex > 0)
{
_bufferList.RemoveRange(0, _currentBufferRequestIndex);
_currentBufferRequestIndex = 0;
}
IList <byte[]> blockHashes =
_blobHasher.CalculateBlockHashes(_chunkBuffer, 0, chunkSizeToWrite);
_blockHashes.AddRange(blockHashes);
bytesInWebRequest = chunkSizeToWrite;
start = _position;
webRequestBuffer = _chunkBuffer;
}
if (webRequestBuffer != null)
{
HttpResponseMessage request = await ExecutePutRequestAsync(start, bytesInWebRequest, uploadComplete, webRequestBuffer).ConfigureAwait(false);
if (!request.IsSuccessStatusCode)
{
ThrowRequestFailedException(request);
}
_bytesInBuffer -= chunkSizeToWrite;
}
_position += chunkSizeToWrite;
}
private void AugmentBufferList(BufferRequest buffer)
{
_bufferList.Add(buffer);
_bytesInBuffer += buffer.Count;
}
private void AugmentBufferList(BufferRequest buffer)
{
_bufferList.Add(buffer);
_bytesInBuffer += buffer.Count;
}
