Build a UI and ensure there are bytes to read to avoid locking on ReadByte call

GPSDOTimeSync/FormMain.Designer.cs

@@ -23,27 +23,25 @@
 		/// the contents of this method with the code editor.
 		/// </summary>
 		private void InitializeComponent() {
-			this.labelTimestamps = new System.Windows.Forms.Label();
 			this.statusStrip = new System.Windows.Forms.StatusStrip();
 			this.latestLogMessage = new System.Windows.Forms.ToolStripStatusLabel();
+			this.serialPortNames = new System.Windows.Forms.ComboBox();
+			this.serialPortNamesLabel = new System.Windows.Forms.Label();
+			this.start = new System.Windows.Forms.Button();
+			this.stop = new System.Windows.Forms.Button();
+			this.deviceLabel = new System.Windows.Forms.Label();
+			this.deviceNames = new System.Windows.Forms.ComboBox();
 			this.statusStrip.SuspendLayout();
 			this.SuspendLayout();
 			// 
-			// labelTimestamps
-			// 
-			this.labelTimestamps.Dock = System.Windows.Forms.DockStyle.Fill;
-			this.labelTimestamps.Location = new System.Drawing.Point(0, 0);
-			this.labelTimestamps.Name = "labelTimestamps";
-			this.labelTimestamps.Size = new System.Drawing.Size(486, 358);
-			this.labelTimestamps.TabIndex = 0;
-			// 
 			// statusStrip
 			// 
 			this.statusStrip.Items.AddRange(new System.Windows.Forms.ToolStripItem[] {
             this.latestLogMessage});
-			this.statusStrip.Location = new System.Drawing.Point(0, 336);
+			this.statusStrip.Location = new System.Drawing.Point(0, 99);
 			this.statusStrip.Name = "statusStrip";
-			this.statusStrip.Size = new System.Drawing.Size(486, 22);
+			this.statusStrip.Size = new System.Drawing.Size(224, 22);
+			this.statusStrip.SizingGrip = false;
 			this.statusStrip.TabIndex = 1;
 			this.statusStrip.Text = "statusStrip1";
 			// 
@@ -51,16 +49,79 @@
 			// 
 			this.latestLogMessage.ForeColor = System.Drawing.Color.Black;
 			this.latestLogMessage.Name = "latestLogMessage";
-			this.latestLogMessage.Size = new System.Drawing.Size(66, 17);
+			this.latestLogMessage.Size = new System.Drawing.Size(178, 17);
+			this.latestLogMessage.Spring = true;
 			this.latestLogMessage.Text = "{RUNTIME}";
 			// 
+			// serialPortNames
+			// 
+			this.serialPortNames.DropDownStyle = System.Windows.Forms.ComboBoxStyle.DropDownList;
+			this.serialPortNames.FormattingEnabled = true;
+			this.serialPortNames.Location = new System.Drawing.Point(76, 39);
+			this.serialPortNames.Name = "serialPortNames";
+			this.serialPortNames.Size = new System.Drawing.Size(121, 21);
+			this.serialPortNames.TabIndex = 2;
+			// 
+			// serialPortNamesLabel
+			// 
+			this.serialPortNamesLabel.AutoSize = true;
+			this.serialPortNamesLabel.Location = new System.Drawing.Point(12, 42);
+			this.serialPortNamesLabel.Name = "serialPortNamesLabel";
+			this.serialPortNamesLabel.Size = new System.Drawing.Size(55, 13);
+			this.serialPortNamesLabel.TabIndex = 3;
+			this.serialPortNamesLabel.Text = "Serial Port";
+			// 
+			// start
+			// 
+			this.start.Location = new System.Drawing.Point(12, 66);
+			this.start.Name = "start";
+			this.start.Size = new System.Drawing.Size(75, 23);
+			this.start.TabIndex = 4;
+			this.start.Text = "Start";
+			this.start.UseVisualStyleBackColor = true;
+			this.start.Click += new System.EventHandler(this.start_Click);
+			// 
+			// stop
+			// 
+			this.stop.Enabled = false;
+			this.stop.Location = new System.Drawing.Point(93, 66);
+			this.stop.Name = "stop";
+			this.stop.Size = new System.Drawing.Size(75, 23);
+			this.stop.TabIndex = 5;
+			this.stop.Text = "Stop";
+			this.stop.UseVisualStyleBackColor = true;
+			this.stop.Click += new System.EventHandler(this.stop_Click);
+			// 
+			// deviceLabel
+			// 
+			this.deviceLabel.AutoSize = true;
+			this.deviceLabel.Location = new System.Drawing.Point(12, 15);
+			this.deviceLabel.Name = "deviceLabel";
+			this.deviceLabel.Size = new System.Drawing.Size(41, 13);
+			this.deviceLabel.TabIndex = 6;
+			this.deviceLabel.Text = "Device";
+			// 
+			// deviceNames
+			// 
+			this.deviceNames.DropDownStyle = System.Windows.Forms.ComboBoxStyle.DropDownList;
+			this.deviceNames.FormattingEnabled = true;
+			this.deviceNames.Location = new System.Drawing.Point(76, 12);
+			this.deviceNames.Name = "deviceNames";
+			this.deviceNames.Size = new System.Drawing.Size(121, 21);
+			this.deviceNames.TabIndex = 7;
+			// 
 			// FormMain
 			// 
 			this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
 			this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
-			this.ClientSize = new System.Drawing.Size(486, 358);
+			this.ClientSize = new System.Drawing.Size(224, 121);
+			this.Controls.Add(this.deviceNames);
+			this.Controls.Add(this.deviceLabel);
+			this.Controls.Add(this.stop);
+			this.Controls.Add(this.start);
+			this.Controls.Add(this.serialPortNamesLabel);
+			this.Controls.Add(this.serialPortNames);
 			this.Controls.Add(this.statusStrip);
-			this.Controls.Add(this.labelTimestamps);
 			this.Name = "FormMain";
 			this.Text = "GPSDO Time Sync";
 			this.FormClosing += new System.Windows.Forms.FormClosingEventHandler(this.FormMain_FormClosing);
@@ -72,10 +133,14 @@
 		}
 
 		#endregion
-
-		private System.Windows.Forms.Label labelTimestamps;
 		private System.Windows.Forms.StatusStrip statusStrip;
 		private System.Windows.Forms.ToolStripStatusLabel latestLogMessage;
+		private System.Windows.Forms.ComboBox serialPortNames;
+		private System.Windows.Forms.Label serialPortNamesLabel;
+		private System.Windows.Forms.Button start;
+		private System.Windows.Forms.Button stop;
+		private System.Windows.Forms.Label deviceLabel;
+		private System.Windows.Forms.ComboBox deviceNames;
 	}
 }
 

GPSDOTimeSync/FormMain.cs

@@ -15,6 +15,18 @@ namespace GPSDOTimeSync {
 			{ LogLevel.Error, Color.Red }
 		};
 
+		private static readonly Dictionary<string, Func<SerialPort, ITimeProvider>> TIME_PROVIDER_CONSTRUCTORS = new Dictionary<string, Func<SerialPort, ITimeProvider>>() {
+			{
+				"Trimble Thunderbolt",
+				new Func<SerialPort, ITimeProvider>((serialPort) => {
+					ThunderboltSerialPort thunderboltSerialPort = new ThunderboltSerialPort(serialPort);
+					ITimeProvider timeProvider = new ThunderboltTimeProvider(thunderboltSerialPort);
+
+					return timeProvider;
+				})
+			}
+		};
+
 		private ITimeProvider timeProvider;
 
 		public FormMain() {
@@ -30,15 +42,50 @@ namespace GPSDOTimeSync {
 			//     Quit
 
 			InitializeComponent();
+			PopulateDropDowns();
 
+			statusStrip.Renderer = new TruncatedTextEllipsisRenderer();
 			latestLogMessage.Text = "";
+		}
+
+		private void PopulateDropDowns() {
+			foreach (string portName in SerialPort.GetPortNames()) {
+				serialPortNames.Items.Add(portName);
+			}
+
+			if (serialPortNames.Items.Count > 0) {
+				serialPortNames.SelectedIndex = 0;
+			}
+
+			foreach (string deviceName in TIME_PROVIDER_CONSTRUCTORS.Keys) {
+				deviceNames.Items.Add(deviceName);
+			}
+
+			if (deviceNames.Items.Count > 0) {
+				deviceNames.SelectedIndex = 0;
+			}
+		}
+
+		private void AddMessageToLog(string message, LogLevel logLevel) {
+			latestLogMessage.Text = string.Format("{0} ({1})", message, DateTime.Now.ToString("G"));
+			latestLogMessage.ForeColor = LOG_LEVEL_TO_COLOR[logLevel];
+		}
 
-			ThunderboltSerialPort thunderboltSerialPort = new ThunderboltSerialPort(new SerialPort("COM3"));
-			timeProvider = new ThunderboltTimeProvider(thunderboltSerialPort);
+		private void start_Click(object sender, EventArgs e) {
+			string serialPortName = (string) serialPortNames.SelectedItem;
+			string deviceName = (string) deviceNames.SelectedItem;
+
+			SerialPort serialPort = new SerialPort(serialPortName);		
+			timeProvider = TIME_PROVIDER_CONSTRUCTORS[deviceName](serialPort);
 
 			timeProvider.TimeAvailable += (DateTime dateTime) => {
 				Invoke(new Action(() => {
-					labelTimestamps.Text += string.Format("{0} {1}\n", dateTime.ToLongDateString(), dateTime.ToLongTimeString());
+					AddMessageToLog(
+						string.Format(
+								"Time is {0} {1}",
+								dateTime.ToLongDateString(), dateTime.ToLongTimeString()
+						), LogLevel.Info
+					);
 				}));
 			};
 
@@ -49,15 +96,34 @@ namespace GPSDOTimeSync {
 			};
 
 			timeProvider.Start();
+
+			AddMessageToLog("Time sync started.", LogLevel.Info);
+
+			start.Enabled = false;
+			stop.Enabled = true;
 		}
 
-		private void AddMessageToLog(string message, LogLevel logLevel) {
-			latestLogMessage.Text = string.Format("{0} ({1})", message, DateTime.Now.ToString("G"));
-			latestLogMessage.ForeColor = LOG_LEVEL_TO_COLOR[logLevel];
+		private void stop_Click(object sender, EventArgs e) {
+			timeProvider.Stop();
+
+			AddMessageToLog("Time sync stopped.", LogLevel.Info);
+
+			stop.Enabled = false;
+			start.Enabled = true;
 		}
 
 		private void FormMain_FormClosing(object sender, FormClosingEventArgs e) {
-			timeProvider.Stop();
+			timeProvider?.Stop();
+		}
+	}
+
+	public class TruncatedTextEllipsisRenderer : ToolStripProfessionalRenderer {
+		protected override void OnRenderItemText(ToolStripItemTextRenderEventArgs e) {
+			if (e.Item is ToolStripStatusLabel) {
+				TextRenderer.DrawText(e.Graphics, e.Text, e.TextFont, e.TextRectangle, e.TextColor, Color.Transparent, e.TextFormat | TextFormatFlags.EndEllipsis);
+			} else {
+				base.OnRenderItemText(e);
+			}
 		}
 	}
 }

GPSDOTimeSync/GPSDOTimeSync.csproj

@@ -91,4 +91,4 @@
   <Target Name="AfterBuild">
   </Target>
   -->
-</Project>
+</Project>

GPSDOTimeSync/TimeProviders/Thunderbolt/ThunderboltSerialPort.cs

@@ -73,6 +73,7 @@ namespace GPSDOTimeSync.Devices.Thunderbolt {
 			this.serialPort = serialPort;
 
 			readThread = new Thread(ReadSerialPort);
+			readThread.Name = "ThunderboltSerialPort Read";
 		}
 
 		/// <summary>
@@ -201,12 +202,14 @@ namespace GPSDOTimeSync.Devices.Thunderbolt {
 
 		private void ReadSerialPort() {
 			while (running) {
-				int possibleCurrentByte = serialPort.ReadByte();
+				if (serialPort.BytesToRead > 0) {
+					int possibleCurrentByte = serialPort.ReadByte();
 
-				if (possibleCurrentByte != -1) {
-					// Once we're sure the byte that was read wasn't -1 (which signifies the end of the read), we're safe to cast to a byte
-					ProcessByte((byte) possibleCurrentByte);
-				}
+					if (possibleCurrentByte != -1) {
+						// Once we're sure the byte that was read wasn't -1 (which signifies the end of the read), we're safe to cast to a byte
+						ProcessByte((byte) possibleCurrentByte);
+					}
+				}				
 			}
 		}
 	}