Nullable annotate System.IO.Pipes (#31918)

* annotate System.IO.Pipes

* update Stream override method signatures

src/libraries/Common/src/Interop/Windows/Kernel32/Interop.CreateNamedPipeClient.cs

@@ -13,7 +13,7 @@ internal partial class Kernel32
     {
         [DllImport(Libraries.Kernel32, EntryPoint = "CreateFileW", CharSet = CharSet.Unicode, SetLastError = true, BestFitMapping = false)]
         internal static extern SafePipeHandle CreateNamedPipeClient(
-            string lpFileName,
+            string? lpFileName,
             int dwDesiredAccess,
             System.IO.FileShare dwShareMode,
             ref SECURITY_ATTRIBUTES secAttrs,

src/libraries/Common/src/Interop/Windows/Kernel32/Interop.WaitNamedPipe.cs

@@ -10,6 +10,6 @@ internal partial class Kernel32
     {
         [DllImport(Libraries.Kernel32, CharSet = CharSet.Unicode, SetLastError = true, BestFitMapping = false, EntryPoint = "WaitNamedPipeW")]
         [return: MarshalAs(UnmanagedType.Bool)]
-        internal static extern bool WaitNamedPipe(string name, int timeout);
+        internal static extern bool WaitNamedPipe(string? name, int timeout);
     }
 }

src/libraries/System.IO.Pipes/ref/System.IO.Pipes.cs

@@ -111,16 +111,17 @@ protected PipeStream(System.IO.Pipes.PipeDirection direction, System.IO.Pipes.Pi
         public virtual System.IO.Pipes.PipeTransmissionMode ReadMode { get { throw null; } set { } }
         public Microsoft.Win32.SafeHandles.SafePipeHandle SafePipeHandle { get { throw null; } }
         public virtual System.IO.Pipes.PipeTransmissionMode TransmissionMode { get { throw null; } }
-        public override System.IAsyncResult BeginRead(byte[] buffer, int offset, int count, System.AsyncCallback callback, object state) { throw null; }
-        public override System.IAsyncResult BeginWrite(byte[] buffer, int offset, int count, System.AsyncCallback callback, object state) { throw null; }
+        public override System.IAsyncResult BeginRead(byte[] buffer, int offset, int count, System.AsyncCallback? callback, object? state) { throw null; }
+        public override System.IAsyncResult BeginWrite(byte[] buffer, int offset, int count, System.AsyncCallback? callback, object? state) { throw null; }
         protected internal virtual void CheckPipePropertyOperations() { }
         protected internal void CheckReadOperations() { }
         protected internal void CheckWriteOperations() { }
         protected override void Dispose(bool disposing) { }
         public override int EndRead(System.IAsyncResult asyncResult) { throw null; }
         public override void EndWrite(System.IAsyncResult asyncResult) { }
         public override void Flush() { }
-        protected void InitializeHandle(Microsoft.Win32.SafeHandles.SafePipeHandle handle, bool isExposed, bool isAsync) { }
+        public override System.Threading.Tasks.Task FlushAsync(System.Threading.CancellationToken cancellationToken) { throw null; }
+        protected void InitializeHandle(Microsoft.Win32.SafeHandles.SafePipeHandle? handle, bool isExposed, bool isAsync) { }
         public override int Read(byte[] buffer, int offset, int count) { throw null; }
         public override int Read(System.Span<byte> buffer) { throw null; }
         public override System.Threading.Tasks.Task<int> ReadAsync(byte[] buffer, int offset, int count, System.Threading.CancellationToken cancellationToken) { throw null; }

src/libraries/System.IO.Pipes/ref/System.IO.Pipes.csproj

@@ -1,6 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFrameworks>$(NetCoreAppCurrent)</TargetFrameworks>
+    <Nullable>enable</Nullable>
   </PropertyGroup>
   <ItemGroup>
     <Compile Include="System.IO.Pipes.cs" />

src/libraries/System.IO.Pipes/src/Microsoft/Win32/SafeHandles/SafePipeHandle.Unix.cs

@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+#nullable enable
 using System;
 using System.Diagnostics;
 using System.Net.Sockets;
@@ -22,8 +23,8 @@ public sealed partial class SafePipeHandle : SafeHandleZeroOrMinusOneIsInvalid
         // and operations that should go through the Socket to be done via _namedPipeSocket.  We keep the
         // Socket's SafeHandle alive as long as this SafeHandle is alive.
 
-        private Socket _namedPipeSocket;
-        private SafeHandle _namedPipeSocketHandle;
+        private Socket? _namedPipeSocket;
+        private SafeHandle? _namedPipeSocketHandle;
 
         internal SafePipeHandle(Socket namedPipeSocket) : base(ownsHandle: true)
         {
@@ -37,8 +38,8 @@ internal SafePipeHandle(Socket namedPipeSocket) : base(ownsHandle: true)
             SetHandle(_namedPipeSocketHandle.DangerousGetHandle());
         }
 
-        internal Socket NamedPipeSocket => _namedPipeSocket;
-        internal SafeHandle NamedPipeSocketHandle => _namedPipeSocketHandle;
+        internal Socket? NamedPipeSocket => _namedPipeSocket;
+        internal SafeHandle? NamedPipeSocketHandle => _namedPipeSocketHandle;
 
         protected override void Dispose(bool disposing)
         {

src/libraries/System.IO.Pipes/src/Microsoft/Win32/SafeHandles/SafePipeHandle.cs

@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+#nullable enable
 using System;
 using System.Runtime.InteropServices;
 using System.Security;

src/libraries/System.IO.Pipes/src/System.IO.Pipes.csproj

@@ -4,6 +4,7 @@
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
     <OmitTransitiveCompileReferences>true</OmitTransitiveCompileReferences>
     <TargetFrameworks>$(NetCoreAppCurrent)-Windows_NT;$(NetCoreAppCurrent)-Unix</TargetFrameworks>
+    <Nullable>enable</Nullable>
   </PropertyGroup>
   <!-- Compiled Source Files -->
   <ItemGroup>

src/libraries/System.IO.Pipes/src/System/IO/Pipes/AnonymousPipeServerStream.Windows.cs

@@ -34,7 +34,7 @@ private void Create(PipeDirection direction, HandleInheritability inheritability
             Create(direction, inheritability, bufferSize, null);
         }
 
-        private void Create(PipeDirection direction, HandleInheritability inheritability, int bufferSize, PipeSecurity pipeSecurity)
+        private void Create(PipeDirection direction, HandleInheritability inheritability, int bufferSize, PipeSecurity? pipeSecurity)
         {
             Debug.Assert(direction != PipeDirection.InOut, "Anonymous pipe direction shouldn't be InOut");
             Debug.Assert(bufferSize >= 0, "bufferSize is negative");

src/libraries/System.IO.Pipes/src/System/IO/Pipes/AnonymousPipeServerStream.cs

@@ -12,7 +12,7 @@ namespace System.IO.Pipes
     /// </summary>
     public sealed partial class AnonymousPipeServerStream : PipeStream
     {
-        private SafePipeHandle _clientHandle;
+        private SafePipeHandle _clientHandle = null!;
         private bool _clientHandleExposed;
 
         public AnonymousPipeServerStream()

src/libraries/System.IO.Pipes/src/System/IO/Pipes/ConnectionCompletionSource.cs

@@ -13,7 +13,7 @@ internal sealed class ConnectionCompletionSource : PipeCompletionSource<VoidResu
 
         // Using RunContinuationsAsynchronously for compat reasons (old API used ThreadPool.QueueUserWorkItem for continuations)
         internal ConnectionCompletionSource(NamedPipeServerStream server)
-            : base(server._threadPoolBinding, ReadOnlyMemory<byte>.Empty)
+            : base(server._threadPoolBinding!, ReadOnlyMemory<byte>.Empty)
         {
             _serverStream = server;
         }

src/libraries/System.IO.Pipes/src/System/IO/Pipes/NamedPipeClientStream.Unix.cs

@@ -25,7 +25,7 @@ private bool TryConnect(int timeout, CancellationToken cancellationToken)
             // immediately if it isn't.  The only delay will be between the time the server
             // has called Bind and Listen, with the latter immediately following the former.
             var socket = new Socket(AddressFamily.Unix, SocketType.Stream, ProtocolType.Unspecified);
-            SafePipeHandle clientHandle = null;
+            SafePipeHandle? clientHandle = null;
             try
             {
                 socket.Connect(new UnixDomainSocketEndPoint(_normalizedPipePath));

src/libraries/System.IO.Pipes/src/System/IO/Pipes/NamedPipeClientStream.Windows.cs

@@ -120,7 +120,7 @@ public unsafe int NumberOfServerInstances
                 // access request before calling NTCreateFile, so all NamedPipeClientStreams can read
                 // this if they are created (on WinXP SP2 at least)]
                 uint numInstances;
-                if (!Interop.Kernel32.GetNamedPipeHandleStateW(InternalHandle, null, &numInstances, null, null, null, 0))
+                if (!Interop.Kernel32.GetNamedPipeHandleStateW(InternalHandle!, null, &numInstances, null, null, null, 0))
                 {
                     throw WinIOError(Marshal.GetLastWin32Error());
                 }
@@ -135,10 +135,10 @@ private void ValidateRemotePipeUser()
                 return;
 
             PipeSecurity accessControl = this.GetAccessControl();
-            IdentityReference remoteOwnerSid = accessControl.GetOwner(typeof(SecurityIdentifier));
+            IdentityReference? remoteOwnerSid = accessControl.GetOwner(typeof(SecurityIdentifier));
             using (WindowsIdentity currentIdentity = WindowsIdentity.GetCurrent())
             {
-                SecurityIdentifier currentUserSid = currentIdentity.Owner;
+                SecurityIdentifier? currentUserSid = currentIdentity.Owner;
                 if (remoteOwnerSid != currentUserSid)
                 {
                     State = PipeState.Closed;

src/libraries/System.IO.Pipes/src/System/IO/Pipes/NamedPipeClientStream.cs

@@ -20,7 +20,7 @@ public sealed partial class NamedPipeClientStream : PipeStream
         // Maximum interval in milliseconds between which cancellation is checked.
         // Used by ConnectInternal. 50ms is fairly responsive time but really long time for processor.
         private const int CancellationCheckInterval = 50;
-        private readonly string _normalizedPipePath;
+        private readonly string? _normalizedPipePath;
         private readonly TokenImpersonationLevel _impersonationLevel;
         private readonly PipeOptions _pipeOptions;
         private readonly HandleInheritability _inheritability;

src/libraries/System.IO.Pipes/src/System/IO/Pipes/NamedPipeServerStream.Unix.cs

@@ -15,7 +15,7 @@ namespace System.IO.Pipes
 {
     public sealed partial class NamedPipeServerStream : PipeStream
     {
-        private SharedServer _instance;
+        private SharedServer? _instance;
         private PipeDirection _direction;
         private PipeOptions _options;
         private int _inBufferSize;
@@ -62,7 +62,7 @@ public void WaitForConnection()
 
             // Use and block on AcceptAsync() rather than using Accept() in order to provide
             // behavior more akin to Windows if the Stream is closed while a connection is pending.
-            Socket accepted = _instance.ListeningSocket.AcceptAsync().GetAwaiter().GetResult();
+            Socket accepted = _instance!.ListeningSocket.AcceptAsync().GetAwaiter().GetResult();
             HandleAcceptedSocket(accepted);
         }
 
@@ -79,7 +79,7 @@ public Task WaitForConnectionAsync(CancellationToken cancellationToken)
                 WaitForConnectionAsyncCore();
 
             async Task WaitForConnectionAsyncCore() =>
-               HandleAcceptedSocket(await _instance.ListeningSocket.AcceptAsync().ConfigureAwait(false));
+               HandleAcceptedSocket(await _instance!.ListeningSocket.AcceptAsync().ConfigureAwait(false));
         }
 
         private void HandleAcceptedSocket(Socket acceptedSocket)
@@ -124,7 +124,7 @@ public void Disconnect()
         {
             CheckDisconnectOperations();
             State = PipeState.Disconnected;
-            InternalHandle.Dispose();
+            InternalHandle!.Dispose();
             InitializeHandle(null, false, false);
         }
 
@@ -135,7 +135,7 @@ public string GetImpersonationUserName()
         {
             CheckWriteOperations();
 
-            SafeHandle handle = InternalHandle?.NamedPipeSocketHandle;
+            SafeHandle? handle = InternalHandle?.NamedPipeSocketHandle;
             if (handle == null)
             {
                 throw new InvalidOperationException(SR.InvalidOperation_PipeHandleNotSet);
@@ -178,7 +178,7 @@ public override int OutBufferSize
         public void RunAsClient(PipeStreamImpersonationWorker impersonationWorker)
         {
             CheckWriteOperations();
-            SafeHandle handle = InternalHandle?.NamedPipeSocketHandle;
+            SafeHandle? handle = InternalHandle?.NamedPipeSocketHandle;
             if (handle == null)
             {
                 throw new InvalidOperationException(SR.InvalidOperation_PipeHandleNotSet);
@@ -233,7 +233,7 @@ internal static SharedServer Get(string path, int maxCount)
 
                 lock (s_servers)
                 {
-                    SharedServer server;
+                    SharedServer? server;
                     if (s_servers.TryGetValue(path, out server))
                     {
                         // On Windows, if a subsequent server stream is created for the same pipe and with a different

src/libraries/System.IO.Pipes/src/System/IO/Pipes/NamedPipeServerStream.Win32.cs

@@ -23,7 +23,7 @@ private unsafe string HandleGetImpersonationUserNameError(int error, uint userNa
             {
                 Interop.Kernel32.LoadLibraryEx("sspicli.dll", IntPtr.Zero, Interop.Kernel32.LOAD_LIBRARY_SEARCH_SYSTEM32);
 
-                if (Interop.Kernel32.GetNamedPipeHandleStateW(InternalHandle, null, null, null, null, userName, userNameMaxLength))
+                if (Interop.Kernel32.GetNamedPipeHandleStateW(InternalHandle!, null, null, null, null, userName, userNameMaxLength))
                 {
                     return new string(userName);
                 }

src/libraries/System.IO.Pipes/src/System/IO/Pipes/NamedPipeServerStream.Windows.cs

@@ -53,7 +53,7 @@ private void Create(string pipeName, PipeDirection direction, int maxNumberOfSer
         // This overload is used in Mono to implement public constructors.
         private void Create(string pipeName, PipeDirection direction, int maxNumberOfServerInstances,
                 PipeTransmissionMode transmissionMode, PipeOptions options, int inBufferSize, int outBufferSize,
-                PipeSecurity pipeSecurity, HandleInheritability inheritability, PipeAccessRights additionalAccessRights)
+                PipeSecurity? pipeSecurity, HandleInheritability inheritability, PipeAccessRights additionalAccessRights)
         {
             Debug.Assert(pipeName != null && pipeName.Length != 0, "fullPipeName is null or empty");
             Debug.Assert(direction >= PipeDirection.In && direction <= PipeDirection.InOut, "invalid pipe direction");
@@ -76,7 +76,7 @@ private void Create(string pipeName, PipeDirection direction, int maxNumberOfSer
 
                 using (WindowsIdentity currentIdentity = WindowsIdentity.GetCurrent())
                 {
-                    SecurityIdentifier identifier = currentIdentity.Owner;
+                    SecurityIdentifier identifier = currentIdentity.Owner!;
 
                     // Grant full control to the owner so multiple servers can be opened.
                     // Full control is the default per MSDN docs for CreateNamedPipe.
@@ -145,7 +145,7 @@ public void WaitForConnection()
             }
             else
             {
-                if (!Interop.Kernel32.ConnectNamedPipe(InternalHandle, IntPtr.Zero))
+                if (!Interop.Kernel32.ConnectNamedPipe(InternalHandle!, IntPtr.Zero))
                 {
                     int errorCode = Marshal.GetLastWin32Error();
 
@@ -177,7 +177,7 @@ public Task WaitForConnectionAsync(CancellationToken cancellationToken)
 
             if (!IsAsync)
             {
-                return Task.Factory.StartNew(s => ((NamedPipeServerStream)s).WaitForConnection(),
+                return Task.Factory.StartNew(s => ((NamedPipeServerStream)s!).WaitForConnection(),
                     this, cancellationToken, TaskCreationOptions.DenyChildAttach, TaskScheduler.Default);
             }
 
@@ -189,7 +189,7 @@ public void Disconnect()
             CheckDisconnectOperations();
 
             // Disconnect the pipe.
-            if (!Interop.Kernel32.DisconnectNamedPipe(InternalHandle))
+            if (!Interop.Kernel32.DisconnectNamedPipe(InternalHandle!))
             {
                 throw Win32Marshal.GetExceptionForLastWin32Error();
             }
@@ -207,7 +207,7 @@ public unsafe string GetImpersonationUserName()
             const uint UserNameMaxLength = Interop.Kernel32.CREDUI_MAX_USERNAME_LENGTH + 1;
             char* userName = stackalloc char[(int)UserNameMaxLength]; // ~1K
 
-            if (Interop.Kernel32.GetNamedPipeHandleStateW(InternalHandle, null, null, null, null, userName, UserNameMaxLength))
+            if (Interop.Kernel32.GetNamedPipeHandleStateW(InternalHandle!, null, null, null, null, userName, UserNameMaxLength))
             {
                 return new string(userName);
             }
@@ -244,11 +244,11 @@ public void RunAsClient(PipeStreamImpersonationWorker impersonationWorker)
         private static readonly RuntimeHelpers.TryCode tryCode = new RuntimeHelpers.TryCode(ImpersonateAndTryCode);
         private static readonly RuntimeHelpers.CleanupCode cleanupCode = new RuntimeHelpers.CleanupCode(RevertImpersonationOnBackout);
 
-        private static void ImpersonateAndTryCode(object helper)
+        private static void ImpersonateAndTryCode(object? helper)
         {
-            ExecuteHelper execHelper = (ExecuteHelper)helper;
+            ExecuteHelper execHelper = (ExecuteHelper)helper!;
 
-            if (Interop.Advapi32.ImpersonateNamedPipeClient(execHelper._handle))
+            if (Interop.Advapi32.ImpersonateNamedPipeClient(execHelper._handle!))
             {
                 execHelper._mustRevert = true;
             }
@@ -264,9 +264,9 @@ private static void ImpersonateAndTryCode(object helper)
             }
         }
 
-        private static void RevertImpersonationOnBackout(object helper, bool exceptionThrown)
+        private static void RevertImpersonationOnBackout(object? helper, bool exceptionThrown)
         {
-            ExecuteHelper execHelper = (ExecuteHelper)helper;
+            ExecuteHelper execHelper = (ExecuteHelper)helper!;
 
             if (execHelper._mustRevert)
             {
@@ -280,12 +280,12 @@ private static void RevertImpersonationOnBackout(object helper, bool exceptionTh
         internal class ExecuteHelper
         {
             internal PipeStreamImpersonationWorker _userCode;
-            internal SafePipeHandle _handle;
+            internal SafePipeHandle? _handle;
             internal bool _mustRevert;
             internal int _impersonateErrorCode;
             internal int _revertImpersonateErrorCode;
 
-            internal ExecuteHelper(PipeStreamImpersonationWorker userCode, SafePipeHandle handle)
+            internal ExecuteHelper(PipeStreamImpersonationWorker userCode, SafePipeHandle? handle)
             {
                 _userCode = userCode;
                 _handle = handle;
@@ -304,7 +304,7 @@ private unsafe Task WaitForConnectionCoreAsync(CancellationToken cancellationTok
 
             var completionSource = new ConnectionCompletionSource(this);
 
-            if (!Interop.Kernel32.ConnectNamedPipe(InternalHandle, completionSource.Overlapped))
+            if (!Interop.Kernel32.ConnectNamedPipe(InternalHandle!, completionSource.Overlapped))
             {
                 int errorCode = Marshal.GetLastWin32Error();
 

src/libraries/System.IO.Pipes/src/System/IO/Pipes/PipeCompletionSource.cs

@@ -43,7 +43,7 @@ protected PipeCompletionSource(ThreadPoolBoundHandle handle, ReadOnlyMemory<byte
             _pinnedMemory = bufferToPin.Pin();
             _overlapped = _threadPoolBinding.AllocateNativeOverlapped((errorCode, numBytes, pOverlapped) =>
             {
-                var completionSource = (PipeCompletionSource<TResult>)ThreadPoolBoundHandle.GetNativeOverlappedState(pOverlapped);
+                var completionSource = (PipeCompletionSource<TResult>)ThreadPoolBoundHandle.GetNativeOverlappedState(pOverlapped)!;
                 Debug.Assert(completionSource.Overlapped == pOverlapped);
 
                 completionSource.AsyncCallback(errorCode, numBytes);
@@ -70,7 +70,7 @@ internal void RegisterForCancellation(CancellationToken cancellationToken)
                 if (state == NoResult)
                 {
                     // Register the cancellation
-                    _cancellationRegistration = cancellationToken.UnsafeRegister(thisRef => ((PipeCompletionSource<TResult>)thisRef).Cancel(), this);
+                    _cancellationRegistration = cancellationToken.UnsafeRegister(thisRef => ((PipeCompletionSource<TResult>)thisRef!).Cancel(), this);
 
                     // Grab the state for case if IO completed while we were setting the registration.
                     state = Interlocked.Exchange(ref _state, NoResult);