diff --git a/src/Microsoft.SqlTools.ServiceLayer/Hosting/Protocol/MessageDispatcher.cs b/src/Microsoft.SqlTools.ServiceLayer/Hosting/Protocol/MessageDispatcher.cs index a18fa806..7cf1f2dd 100644 --- a/src/Microsoft.SqlTools.ServiceLayer/Hosting/Protocol/MessageDispatcher.cs +++ b/src/Microsoft.SqlTools.ServiceLayer/Hosting/Protocol/MessageDispatcher.cs @@ -8,6 +8,7 @@ using System.Collections.Generic; using System.IO; using System.Threading; using System.Threading.Tasks; +using Microsoft.SqlTools.ServiceLayer.Hosting.Contracts; using Microsoft.SqlTools.ServiceLayer.Hosting.Protocol.Channel; using Microsoft.SqlTools.ServiceLayer.Hosting.Protocol.Contracts; using Microsoft.SqlTools.EditorServices.Utility; @@ -198,10 +199,9 @@ namespace Microsoft.SqlTools.ServiceLayer.Hosting.Protocol this.SynchronizationContext = SynchronizationContext.Current; // Run the message loop - bool isRunning = true; - while (isRunning && !cancellationToken.IsCancellationRequested) + while (!cancellationToken.IsCancellationRequested) { - Message newMessage = null; + Message newMessage; try { @@ -210,12 +210,12 @@ namespace Microsoft.SqlTools.ServiceLayer.Hosting.Protocol } catch (MessageParseException e) { - // TODO: Write an error response - - Logger.Write( - LogLevel.Error, - "Could not parse a message that was received:\r\n\r\n" + - e.ToString()); + string message = String.Format("Exception occurred while parsing message: {0}", e.Message); + Logger.Write(LogLevel.Error, message); + await MessageWriter.WriteEvent(HostingErrorEvent.Type, new HostingErrorParams + { + Message = message + }); // Continue the loop continue; @@ -227,8 +227,16 @@ namespace Microsoft.SqlTools.ServiceLayer.Hosting.Protocol } catch (Exception e) { - var b = e.Message; - newMessage = null; + // Log the error and send an error event to the client + string message = String.Format("Exception occurred while receiving message: {0}", e.Message); + Logger.Write(LogLevel.Error, message); + await MessageWriter.WriteEvent(HostingErrorEvent.Type, new HostingErrorParams + { + Message = message + }); + + // Continue the loop + continue; } // The message could be null if there was an error parsing the @@ -236,9 +244,7 @@ namespace Microsoft.SqlTools.ServiceLayer.Hosting.Protocol if (newMessage != null) { // Process the message - await this.DispatchMessage( - newMessage, - this.MessageWriter); + await this.DispatchMessage(newMessage, this.MessageWriter); } } } diff --git a/src/Microsoft.SqlTools.ServiceLayer/Hosting/Protocol/MessageReader.cs b/src/Microsoft.SqlTools.ServiceLayer/Hosting/Protocol/MessageReader.cs index f3857710..4351361f 100644 --- a/src/Microsoft.SqlTools.ServiceLayer/Hosting/Protocol/MessageReader.cs +++ b/src/Microsoft.SqlTools.ServiceLayer/Hosting/Protocol/MessageReader.cs @@ -25,22 +25,22 @@ namespace Microsoft.SqlTools.ServiceLayer.Hosting.Protocol private const int CR = 0x0D; private const int LF = 0x0A; - private static string[] NewLineDelimiters = new string[] { Environment.NewLine }; + private static readonly string[] NewLineDelimiters = { Environment.NewLine }; - private Stream inputStream; - private IMessageSerializer messageSerializer; - private Encoding messageEncoding; + private readonly Stream inputStream; + private readonly IMessageSerializer messageSerializer; + private readonly Encoding messageEncoding; private ReadState readState; private bool needsMoreData = true; private int readOffset; private int bufferEndOffset; - private byte[] messageBuffer = new byte[DefaultBufferSize]; + private byte[] messageBuffer; private int expectedContentLength; private Dictionary messageHeaders; - enum ReadState + private enum ReadState { Headers, Content @@ -85,7 +85,7 @@ namespace Microsoft.SqlTools.ServiceLayer.Hosting.Protocol this.needsMoreData = false; // Do we need to look for message headers? - if (this.readState == ReadState.Headers && + if (this.readState == ReadState.Headers && !this.TryReadMessageHeaders()) { // If we don't have enough data to read headers yet, keep reading @@ -94,7 +94,7 @@ namespace Microsoft.SqlTools.ServiceLayer.Hosting.Protocol } // Do we need to look for message content? - if (this.readState == ReadState.Content && + if (this.readState == ReadState.Content && !this.TryReadMessageContent(out messageContent)) { // If we don't have enough data yet to construct the content, keep reading @@ -106,6 +106,9 @@ namespace Microsoft.SqlTools.ServiceLayer.Hosting.Protocol break; } + // Now that we have a message, reset the buffer's state + ShiftBufferBytesAndShrink(readOffset); + // Get the JObject for the JSON content JObject messageObject = JObject.Parse(messageContent); @@ -162,8 +165,7 @@ namespace Microsoft.SqlTools.ServiceLayer.Hosting.Protocol { int scanOffset = this.readOffset; - // Scan for the final double-newline that marks the - // end of the header lines + // Scan for the final double-newline that marks the end of the header lines while (scanOffset + 3 < this.bufferEndOffset && (this.messageBuffer[scanOffset] != CR || this.messageBuffer[scanOffset + 1] != LF || @@ -173,45 +175,51 @@ namespace Microsoft.SqlTools.ServiceLayer.Hosting.Protocol scanOffset++; } - // No header or body separator found (e.g CRLFCRLF) + // Make sure we haven't reached the end of the buffer without finding a separator (e.g CRLFCRLF) if (scanOffset + 3 >= this.bufferEndOffset) { return false; } - this.messageHeaders = new Dictionary(); + // Convert the header block into a array of lines + var headers = Encoding.ASCII.GetString(this.messageBuffer, this.readOffset, scanOffset) + .Split(NewLineDelimiters, StringSplitOptions.RemoveEmptyEntries); - var headers = - Encoding.ASCII - .GetString(this.messageBuffer, this.readOffset, scanOffset) - .Split(NewLineDelimiters, StringSplitOptions.RemoveEmptyEntries); - - // Read each header and store it in the dictionary - foreach (var header in headers) + try { - int currentLength = header.IndexOf(':'); - if (currentLength == -1) + // Read each header and store it in the dictionary + this.messageHeaders = new Dictionary(); + foreach (var header in headers) { - throw new ArgumentException("Message header must separate key and value using :"); + int currentLength = header.IndexOf(':'); + if (currentLength == -1) + { + throw new ArgumentException("Message header must separate key and value using :"); + } + + var key = header.Substring(0, currentLength); + var value = header.Substring(currentLength + 1).Trim(); + this.messageHeaders[key] = value; } - var key = header.Substring(0, currentLength); - var value = header.Substring(currentLength + 1).Trim(); - this.messageHeaders[key] = value; - } + // Parse out the content length as an int + string contentLengthString; + if (!this.messageHeaders.TryGetValue("Content-Length", out contentLengthString)) + { + throw new MessageParseException("", "Fatal error: Content-Length header must be provided."); + } - // Make sure a Content-Length header was present, otherwise it - // is a fatal error - string contentLengthString = null; - if (!this.messageHeaders.TryGetValue("Content-Length", out contentLengthString)) - { - throw new MessageParseException("", "Fatal error: Content-Length header must be provided."); + // Parse the content length to an integer + if (!int.TryParse(contentLengthString, out this.expectedContentLength)) + { + throw new MessageParseException("", "Fatal error: Content-Length value is not an integer."); + } } - - // Parse the content length to an integer - if (!int.TryParse(contentLengthString, out this.expectedContentLength)) + catch (Exception) { - throw new MessageParseException("", "Fatal error: Content-Length value is not an integer."); + // The content length was invalid or missing. Trash the buffer we've read + ShiftBufferBytesAndShrink(scanOffset + 4); + throw; } // Skip past the headers plus the newline characters @@ -234,31 +242,40 @@ namespace Microsoft.SqlTools.ServiceLayer.Hosting.Protocol } // Convert the message contents to a string using the specified encoding - messageContent = - this.messageEncoding.GetString( - this.messageBuffer, - this.readOffset, - this.expectedContentLength); + messageContent = this.messageEncoding.GetString( + this.messageBuffer, + this.readOffset, + this.expectedContentLength); - // Move the remaining bytes to the front of the buffer for the next message - var remainingByteCount = this.bufferEndOffset - (this.expectedContentLength + this.readOffset); - Buffer.BlockCopy( - this.messageBuffer, - this.expectedContentLength + this.readOffset, - this.messageBuffer, - 0, - remainingByteCount); + readOffset += expectedContentLength; - // Reset the offsets for the next read - this.readOffset = 0; - this.bufferEndOffset = remainingByteCount; - - // Done reading content, now look for headers + // Done reading content, now look for headers for the next message this.readState = ReadState.Headers; return true; } + private void ShiftBufferBytesAndShrink(int bytesToRemove) + { + // Create a new buffer that is shrunken by the number of bytes to remove + // Note: by using Max, we can guarantee a buffer of at least default buffer size + byte[] newBuffer = new byte[Math.Max(messageBuffer.Length - bytesToRemove, DefaultBufferSize)]; + + // If we need to do shifting, do the shifting + if (bytesToRemove <= messageBuffer.Length) + { + // Copy the existing buffer starting at the offset to remove + Buffer.BlockCopy(messageBuffer, bytesToRemove, newBuffer, 0, bufferEndOffset - bytesToRemove); + } + + // Make the new buffer the message buffer + messageBuffer = newBuffer; + + // Reset the read offset and the end offset + readOffset = 0; + bufferEndOffset -= bytesToRemove; + } + #endregion } }