System.Net.Security.SslStreamInternal.ProcessRead C# (CSharp) Метод

        private int ProcessRead(byte[] buffer, int offset, int count, BufferAsyncResult asyncResult)
        {
            ValidateParameters(buffer, offset, count);

            if (Interlocked.Exchange(ref _nestedRead, 1) == 1)
            {
                throw new NotSupportedException(SR.Format(SR.net_io_invalidnestedcall, (asyncResult!=null? "BeginRead":"Read"), "read"));
            }

            // If this is an async operation, get the AsyncProtocolRequest to use.
            // We do this only after we verify we're the sole write operation in flight.
            AsyncProtocolRequest asyncRequest = GetOrCreateProtocolRequest(ref _readProtocolRequest, asyncResult);

            bool failed = false;

            try
            {
                int copyBytes;
                if (InternalBufferCount != 0)
                {
                    copyBytes = InternalBufferCount > count ? count : InternalBufferCount;
                    if (copyBytes != 0)
                    {
                        Buffer.BlockCopy(InternalBuffer, InternalOffset, buffer, offset, copyBytes);
                        SkipBytes(copyBytes);
                    }
                    
                    asyncRequest?.CompleteUser(copyBytes);
                    
                    return copyBytes;
                }

                return StartReading(buffer, offset, count, asyncRequest);
            }
            catch (Exception e)
            {
                _sslState.FinishRead(null);
                failed = true;

                if (e is IOException)
                {
                    throw;
                }

                throw new IOException(SR.net_io_read, e);
            }
            finally
            {
                if (asyncRequest == null || failed)
                {
                    _nestedRead = 0;
                }
            }
        }