Annotate other libraries for nullable reference types

src/Core/ServiceWrapper/Logging/WrapperServiceEventLogProvider.cs

@@ -7,11 +7,11 @@ namespace winsw.Logging
     /// </summary>
     public class WrapperServiceEventLogProvider : IServiceEventLogProvider
     {
-        public WrapperService service { get; set; }
+        public WrapperService? service { get; set; }
 
-        public EventLog locate()
+        public EventLog? locate()
         {
-            WrapperService _service = service;
+            WrapperService? _service = service;
             if (_service != null && !_service.IsShuttingDown)
             {
                 return _service.EventLog;

src/Core/ServiceWrapper/Main.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.Diagnostics;
+using System.Diagnostics.CodeAnalysis;
 using System.IO;
 using System.Reflection;
 using System.Runtime.InteropServices;
@@ -28,7 +29,7 @@ namespace winsw
 
         private readonly Process _process = new Process();
         private readonly ServiceDescriptor _descriptor;
-        private Dictionary<string, string> _envs;
+        private Dictionary<string, string>? _envs;
 
         internal WinSWExtensionManager ExtensionManager { get; private set; }
 
@@ -52,7 +53,7 @@ namespace winsw
         /// <remarks>
         /// The version will be taken from <see cref="AssemblyInfo"/>
         /// </remarks>
-        public static Version Version => Assembly.GetExecutingAssembly().GetName().Version;
+        public static Version Version => Assembly.GetExecutingAssembly().GetName().Version!;
 
         /// <summary>
         /// Indicates that the system is shutting down.
@@ -92,7 +93,7 @@ namespace winsw
             {
                 using (var tr = new StreamReader(file, Encoding.UTF8))
                 {
-                    string line;
+                    string? line;
                     while ((line = tr.ReadLine()) != null)
                     {
                         LogEvent("Handling copy: " + line);
@@ -223,7 +224,7 @@ namespace winsw
                 }
             }
 
-            string startarguments = _descriptor.Startarguments;
+            string? startarguments = _descriptor.Startarguments;
 
             if (startarguments == null)
             {
@@ -282,7 +283,7 @@ namespace winsw
         /// </summary>
         private void StopIt()
         {
-            string stoparguments = _descriptor.Stoparguments;
+            string? stoparguments = _descriptor.Stoparguments;
             LogEvent("Stopping " + _descriptor.Id);
             Log.Info("Stopping " + _descriptor.Id);
             _orderlyShutdown = true;
@@ -307,7 +308,7 @@ namespace winsw
                 stoparguments += " " + _descriptor.Arguments;
 
                 Process stopProcess = new Process();
-                string executable = _descriptor.StopExecutable;
+                string? executable = _descriptor.StopExecutable;
 
                 if (executable == null)
                 {
@@ -399,7 +400,7 @@ namespace winsw
             Advapi32.SetServiceStatus(handle, ref _wrapperServiceStatus);
         }
 
-        private void StartProcess(Process processToStart, string arguments, string executable, LogHandler logHandler, bool redirectStdin)
+        private void StartProcess(Process processToStart, string arguments, string executable, LogHandler? logHandler, bool redirectStdin)
         {
             // Define handler of the completed process
             void OnProcessCompleted(Process proc)
@@ -470,6 +471,7 @@ namespace winsw
             }
         }
 
+        [DoesNotReturn]
         private static void ThrowNoSuchService()
         {
             throw new WmiException(ReturnValue.NoSuchService);
@@ -483,7 +485,7 @@ namespace winsw
         /// <param name="descriptor">Service descriptor. If null, it will be initialized within the method.
         ///                          In such case configs will be loaded from the XML Configuration File.</param>
         /// <exception cref="Exception">Any unhandled exception</exception>
-        public static void Run(string[] _args, ServiceDescriptor descriptor = null)
+        public static void Run(string[] _args, ServiceDescriptor? descriptor = null)
         {
             bool isCLIMode = _args.Length > 0;
 
@@ -538,8 +540,9 @@ namespace winsw
                         throw new Exception("Installation failure: Service with id '" + d.Id + "' already exists");
                     }
 
-                    string username = null, password = null;
+                    string? username = null;
-                    bool setallowlogonasaserviceright = false;
+                    string? password = null;
+                    bool setallowlogonasaserviceright = false; // This variable is very readable.
                     if (args.Count > 1 && args[1] == "/p")
                     {
                         // we expected username/password on stdin
@@ -568,7 +571,7 @@ namespace winsw
 
                     if (setallowlogonasaserviceright)
                     {
-                        LogonAsAService.AddLogonAsAServiceRight(username);
+                        LogonAsAService.AddLogonAsAServiceRight(username!);
                     }
 
                     svc.Create(

src/Core/ServiceWrapper/NullableAttributes.cs

@@ -0,0 +1,8 @@
+#if !NETCOREAPP
+namespace System.Diagnostics.CodeAnalysis
+{
+    /// <summary>Applied to a method that will never return under any circumstance.</summary>
+    [AttributeUsage(AttributeTargets.Method, Inherited = false)]
+    internal sealed class DoesNotReturnAttribute : Attribute { }
+}
+#endif

src/Core/ServiceWrapper/SigIntHelper.cs

@@ -15,7 +15,7 @@ namespace winsw
         private static extern bool FreeConsole();
 
         [DllImport(KERNEL32)]
-        private static extern bool SetConsoleCtrlHandler(ConsoleCtrlDelegate HandlerRoutine, bool Add);
+        private static extern bool SetConsoleCtrlHandler(ConsoleCtrlDelegate? HandlerRoutine, bool Add);
 
         // Delegate type to be used as the Handler Routine for SCCH
         private delegate bool ConsoleCtrlDelegate(CtrlTypes CtrlType);

src/Core/ServiceWrapper/winsw.csproj

@@ -3,6 +3,8 @@
   <PropertyGroup>
     <OutputType>Exe</OutputType>
     <TargetFrameworks>net20;net40;net461;netcoreapp3.1</TargetFrameworks>
+    <LangVersion>latest</LangVersion>
+    <Nullable>enable</Nullable>
     <Version><!-- Populated by AppVeyor --></Version>
     <AssemblyTitle>Windows Service Wrapper</AssemblyTitle>
     <Description>Allows arbitrary process to run as a Windows service by wrapping it.</Description>

src/Core/WinSWCore/Logging/IServiceEventLogProvider.cs

@@ -11,6 +11,6 @@ namespace winsw.Logging
         /// Locates Event Log for the service.
         /// </summary>
         /// <returns>Event Log or null if it is not avilable</returns>
-        EventLog locate();
+        EventLog? locate();
     }
 }

src/Core/WinSWCore/Native/Kernel32.cs

@@ -13,12 +13,17 @@ namespace winsw.Native
         public static extern bool SetStdHandle(int nStdHandle, SafeFileHandle handle);
 
         [DllImport("kernel32.dll", SetLastError = true)]
-        public static extern bool CreateProcess(string lpApplicationName,
+        public static extern bool CreateProcess(
-           string lpCommandLine, IntPtr lpProcessAttributes,
+            string? lpApplicationName,
-           IntPtr lpThreadAttributes, bool bInheritHandles,
+            string lpCommandLine,
-           uint dwCreationFlags, IntPtr lpEnvironment, string lpCurrentDirectory,
+            IntPtr lpProcessAttributes,
-           [In] ref STARTUPINFO lpStartupInfo,
+            IntPtr lpThreadAttributes,
-           out PROCESS_INFORMATION lpProcessInformation);
+            bool bInheritHandles,
+            uint dwCreationFlags,
+            IntPtr lpEnvironment,
+            string? lpCurrentDirectory,
+            [In] ref STARTUPINFO lpStartupInfo,
+            out PROCESS_INFORMATION lpProcessInformation);
 
         [DllImport("kernel32.dll")]
         public static extern int GetLastError();

src/Core/WinSWCore/WmiSchema.cs

@@ -48,7 +48,7 @@ namespace WMI
     public interface Win32Services : IWmiCollection
     {
         // ReturnValue Create(bool desktopInteract, string displayName, int errorControl, string loadOrderGroup, string loadOrderGroupDependencies, string name, string pathName, string serviceDependencies, string serviceType, string startMode, string startName, string startPassword);
-        void Create(string name, string displayName, string pathName, ServiceType serviceType, ErrorControl errorControl, StartMode startMode, bool desktopInteract, string startName, string startPassword, string[] serviceDependencies);
+        void Create(string name, string displayName, string pathName, ServiceType serviceType, ErrorControl errorControl, StartMode startMode, bool desktopInteract, string? startName, string? startPassword, string[] serviceDependencies);
 
         void Create(string name, string displayName, string pathName, ServiceType serviceType, ErrorControl errorControl, StartMode startMode, bool desktopInteract, string[] serviceDependencies);
 

src/Plugins/RunawayProcessKiller/RunawayProcessKiller.csproj

@@ -2,6 +2,8 @@
 
   <PropertyGroup>
     <TargetFrameworks>net20;net40;net461;netcoreapp3.1</TargetFrameworks>
+    <LangVersion>latest</LangVersion>
+    <Nullable>enable</Nullable>
     <Version><!-- Populated by AppVeyor --></Version>
     <RootNamespace>winsw.Plugins.RunawayProcessKiller</RootNamespace>
     <SignAssembly>true</SignAssembly>

src/Plugins/RunawayProcessKiller/RunawayProcessKillerExtension.cs

@@ -40,12 +40,16 @@ namespace winsw.Plugins.RunawayProcessKiller
 
         private static readonly ILog Logger = LogManager.GetLogger(typeof(RunawayProcessKillerExtension));
 
+#pragma warning disable CS8618 // Non-nullable field is uninitialized. Consider declaring as nullable.
         public RunawayProcessKillerExtension()
+#pragma warning restore CS8618 // Non-nullable field is uninitialized. Consider declaring as nullable.
         {
             // Default initializer
         }
 
+#pragma warning disable CS8618 // Non-nullable field is uninitialized. Consider declaring as nullable.
         public RunawayProcessKillerExtension(string pidfile, int stopTimeoutMs = 5000, bool stopParentFirst = false, bool checkWinSWEnvironmentVariable = true)
+#pragma warning restore CS8618 // Non-nullable field is uninitialized. Consider declaring as nullable.
         {
             this.Pidfile = pidfile;
             this.StopTimeout = TimeSpan.FromMilliseconds(stopTimeoutMs);
@@ -57,9 +61,9 @@ namespace winsw.Plugins.RunawayProcessKiller
         {
             // We expect the upper logic to process any errors
             // TODO: a better parser API for types would be useful
-            Pidfile = XmlHelper.SingleElement(node, "pidfile", false);
+            Pidfile = XmlHelper.SingleElement(node, "pidfile", false)!;
-            StopTimeout = TimeSpan.FromMilliseconds(int.Parse(XmlHelper.SingleElement(node, "stopTimeout", false)));
+            StopTimeout = TimeSpan.FromMilliseconds(int.Parse(XmlHelper.SingleElement(node, "stopTimeout", false)!));
-            StopParentProcessFirst = bool.Parse(XmlHelper.SingleElement(node, "stopParentFirst", false));
+            StopParentProcessFirst = bool.Parse(XmlHelper.SingleElement(node, "stopParentFirst", false)!);
             ServiceId = descriptor.Id;
             // TODO: Consider making it documented
             var checkWinSWEnvironmentVariable = XmlHelper.SingleElement(node, "checkWinSWEnvironmentVariable", true);
@@ -117,7 +121,7 @@ namespace winsw.Plugins.RunawayProcessKiller
             }
 
             // Ensure the process references the service
-            string affiliatedServiceId;
+            string? affiliatedServiceId;
             // TODO: This method is not ideal since it works only for vars explicitly mentioned in the start info
             // No Windows 10- compatible solution for EnvVars retrieval, see https://blog.gapotchenko.com/eazfuscator.net/reading-environment-variables
             StringDictionary previousProcessEnvVars = proc.StartInfo.EnvironmentVariables;

src/Plugins/SharedDirectoryMapper/SharedDirectoryMapper.cs

@@ -28,12 +28,12 @@ namespace winsw.Plugins.SharedDirectoryMapper
 
         public override void Configure(ServiceDescriptor descriptor, XmlNode node)
         {
-            var nodes = XmlHelper.SingleNode(node, "mapping", false).SelectNodes("map");
+            var mapNodes = XmlHelper.SingleNode(node, "mapping", false)!.SelectNodes("map");
-            if (nodes != null)
+            if (mapNodes != null)
             {
-                foreach (XmlNode mapNode in nodes)
+                for (int i = 0; i < mapNodes.Count; i++)
                 {
-                    if (mapNode is XmlElement mapElement)
+                    if (mapNodes[i] is XmlElement mapElement)
                     {
                         var config = SharedDirectoryMapperConfig.FromXml(mapElement);
                         _entries.Add(config);

src/Plugins/SharedDirectoryMapper/SharedDirectoryMapper.csproj

@@ -2,6 +2,8 @@
 
   <PropertyGroup>
     <TargetFrameworks>net20;net40;net461;netcoreapp3.1</TargetFrameworks>
+    <LangVersion>latest</LangVersion>
+    <Nullable>enable</Nullable>
     <Version><!-- Populated by AppVeyor --></Version>
     <RootNamespace>winsw.Plugins.SharedDirectoryMapper</RootNamespace>
     <SignAssembly>true</SignAssembly>