Add proper handling of COM port open failure (#33)

Author: josesimoes

source/nanoFirmwareFlasher.sln

@@ -5,6 +5,12 @@ VisualStudioVersion = 16.0.29806.167
 MinimumVisualStudioVersion = 10.0.40219.1
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "nanoFirmwareFlasher", "nanoFirmwareFlasher\nanoFirmwareFlasher.csproj", "{762BA2A1-B3E9-4E26-9491-AE11D1F1C1EA}"
 EndProject
+Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Solution Items", "Solution Items", "{9FD8C426-A16A-49DB-952D-747C3AD96C42}"
+	ProjectSection(SolutionItems) = preProject
+		NuGet.Config = NuGet.Config
+		version.json = version.json
+	EndProjectSection
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|x64 = Debug|x64

source/nanoFirmwareFlasher/EspTool.cs

@@ -163,10 +163,10 @@ internal EspTool(
                     test.Open();
                     test.Close();
                 }
-                catch(IOException)
+                catch
                 {
-                    // presume any IOException here is caused by the serial not existing or not possible to open
-                    return;
+                    // presume any exception here is caused by the serial not existing or not possible to open
+                    throw new EspToolExecutionException();
                 }
             }
 

source/nanoFirmwareFlasher/Exceptions/EspToolExecutionException.cs

@@ -19,6 +19,11 @@ internal class EspToolExecutionException : Exception
         /// </summary>
         public string ExecutionError;
 
+        public EspToolExecutionException() : base()
+        {
+
+        }
+
         public EspToolExecutionException(string message) : base(message)
         {
             ExecutionError = message;

source/nanoFirmwareFlasher/ExitCodes.cs

@@ -77,6 +77,11 @@ public enum ExitCodes : int
         [Display(Name = "Failed to read from ESP32 flash.")]
         E4004 = 4004,
 
+        /// <summary>
+        /// Can't open COM port.
+        /// </summary>
+        [Display(Name = "Failed to open specified COM port.")]
+        E4005 = 4005,
 
         ////////////////////
         // ST Link Errors //

source/nanoFirmwareFlasher/Program.cs

@@ -220,12 +220,22 @@ static async Task RunOptionsAndReturnExitCodeAsync(Options o)
                     _exitCode = ExitCodes.E6001;
                     return;
                 }
+                
+                EspTool espTool;
 
-                var espTool = new EspTool(
-                    o.SerialPort,
-                    o.BaudRate,
-                    o.Esp32FlashMode,
-                    o.Esp32FlashFrequency);
+                try
+                {
+                    espTool = new EspTool(
+                        o.SerialPort,
+                        o.BaudRate,
+                        o.Esp32FlashMode,
+                        o.Esp32FlashFrequency);
+                }
+                catch(Exception)
+                {
+                    _exitCode = ExitCodes.E4005;
+                    return;
+                }
 
                 EspTool.DeviceInfo esp32Device;
 

source/version.json

@@ -1,6 +1,6 @@
 {
   "$schema": "https://raw.githubusercontent.com/AArnott/Nerdbank.GitVersioning/master/src/NerdBank.GitVersioning/version.schema.json",
-  "version": "1.12.0-preview.{height}",
+  "version": "1.12.1-preview.{height}",
   "assemblyVersion": {
     "precision": "revision"
   },