Fixed IDisposable implementation

Author: plasmapper

CHANGELOG.md

@@ -4,6 +4,10 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [Unreleased]
+### Fixed
+- IDisposable implementation.
+
 ## [2.2.0] - 2022-11-12
 ### Changed
 - .NET 6.0 target to .NET Standard 2.0.

PL.Modbus/Client.cs

@@ -13,6 +13,7 @@ namespace PL.Modbus
     /// </summary>
     public class Client : IDisposable
     {
+        private bool _disposed = false;
         private readonly Protocol _protocol;
         private readonly byte _stationAddress;
 
@@ -76,10 +77,21 @@ public int ReadTimeout
 
         public void Dispose()
         {
-            _stream.Close();
+            Dispose(true);
             GC.SuppressFinalize(this);
         }
 
+        protected virtual void Dispose(bool disposing)
+        {
+            if (_disposed)
+                return;
+
+            if (disposing)
+                _stream.Dispose();
+
+            _disposed = true;
+        }
+
         /// <summary>
         /// Executes Modbus command.
         /// </summary>

PL.Modbus/PL.Modbus.csproj

@@ -11,10 +11,10 @@
     <RepositoryUrl>https://github.com/plasmapper/modbus-dotnet</RepositoryUrl>
     <RepositoryType>git</RepositoryType>
     <PackageTags>modbus;client</PackageTags>
-    <PackageReleaseNotes>Changed
-- .NET 6.0 target to .NET Standard 2.0.</PackageReleaseNotes>
+    <PackageReleaseNotes>Fixed
+- IDisposable implementation</PackageReleaseNotes>
     <PackageLicenseExpression>MIT</PackageLicenseExpression>
-    <VersionPrefix>2.2.0</VersionPrefix>
+    <VersionPrefix>2.2.1</VersionPrefix>
   </PropertyGroup>
 
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|AnyCPU'">

PL.Modbus/Stream.cs

@@ -3,14 +3,33 @@
 
 namespace PL.Modbus
 {
-    internal abstract class Stream
+    internal abstract class Stream : IDisposable
     {
+        private bool _disposed = false;
+
         public int ConnectTimeout { get; set; } = 1000;
 
         public int ReadTimeout { get; set; } = 300;
 
         public int DelayBeforeWrite { get; set; } = 0;
 
+        public void Dispose()
+        {
+            Dispose(true);
+            GC.SuppressFinalize(this);
+        }
+
+        protected virtual void Dispose(bool disposing)
+        {
+            if (_disposed)
+                return;
+
+            if (disposing)
+                Close();
+
+            _disposed = true;
+        }
+
         public abstract byte[] Read(int byteCount);
 
         public byte[] ReadTo(byte termByte)