| using System; |
| using System.Collections.Generic; |
| using System.Diagnostics; |
| using System.Text; |
| |
| namespace Thrift.Transport |
| { |
| |
| abstract public class TEndpointTransport : TTransport |
| { |
| protected long MaxMessageSize { get => Configuration.MaxMessageSize; } |
| protected long KnownMessageSize { get; private set; } |
| protected long RemainingMessageSize { get; private set; } |
| |
| private readonly TConfiguration _configuration; |
| public override TConfiguration Configuration { get => _configuration; } |
| |
| public TEndpointTransport( TConfiguration config) |
| { |
| _configuration = config ?? new TConfiguration(); |
| Debug.Assert(Configuration != null); |
| |
| ResetConsumedMessageSize(); |
| } |
| |
| /// <summary> |
| /// Resets RemainingMessageSize to the configured maximum |
| /// </summary> |
| protected void ResetConsumedMessageSize(long newSize = -1) |
| { |
| // full reset |
| if (newSize < 0) |
| { |
| KnownMessageSize = MaxMessageSize; |
| RemainingMessageSize = MaxMessageSize; |
| return; |
| } |
| |
| // update only: message size can shrink, but not grow |
| Debug.Assert(KnownMessageSize <= MaxMessageSize); |
| if (newSize > KnownMessageSize) |
| throw new TTransportException(TTransportException.ExceptionType.EndOfFile, "MaxMessageSize reached"); |
| |
| KnownMessageSize = newSize; |
| RemainingMessageSize = newSize; |
| } |
| |
| /// <summary> |
| /// Updates RemainingMessageSize to reflect then known real message size (e.g. framed transport). |
| /// Will throw if we already consumed too many bytes or if the new size is larger than allowed. |
| /// </summary> |
| /// <param name="size"></param> |
| public override void UpdateKnownMessageSize(long size) |
| { |
| var consumed = KnownMessageSize - RemainingMessageSize; |
| ResetConsumedMessageSize(size); |
| CountConsumedMessageBytes(consumed); |
| } |
| |
| /// <summary> |
| /// Throws if there are not enough bytes in the input stream to satisfy a read of numBytes bytes of data |
| /// </summary> |
| /// <param name="numBytes"></param> |
| public override void CheckReadBytesAvailable(long numBytes) |
| { |
| if (RemainingMessageSize < numBytes) |
| throw new TTransportException(TTransportException.ExceptionType.EndOfFile, "MaxMessageSize reached"); |
| } |
| |
| /// <summary> |
| /// Consumes numBytes from the RemainingMessageSize. |
| /// </summary> |
| /// <param name="numBytes"></param> |
| protected void CountConsumedMessageBytes(long numBytes) |
| { |
| if (RemainingMessageSize >= numBytes) |
| { |
| RemainingMessageSize -= numBytes; |
| } |
| else |
| { |
| RemainingMessageSize = 0; |
| throw new TTransportException(TTransportException.ExceptionType.EndOfFile, "MaxMessageSize reached"); |
| } |
| } |
| } |
| } |