Integrated message thread inside TwainAppSession as a different OpenDSM method.

NTwain.sln

@@ -28,74 +28,96 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "WinForm64", "samples\WinFor
 EndProject
 Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "csizes", "csizes\csizes.vcxproj", "{1AABD2DC-3F81-4301-938B-3EC2EDEF38D4}"
 EndProject
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "WinConsole32", "samples\WinConsole32\WinConsole32.csproj", "{4E2417E7-FDC3-46D7-B976-84A97B500B74}"
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "WinConsole32", "samples\WinConsole32\WinConsole32.csproj", "{4E2417E7-FDC3-46D7-B976-84A97B500B74}"
 EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
+		Debug|ARM64 = Debug|ARM64
 		Debug|x64 = Debug|x64
 		Debug|x86 = Debug|x86
 		Release|Any CPU = Release|Any CPU
+		Release|ARM64 = Release|ARM64
 		Release|x64 = Release|x64
 		Release|x86 = Release|x86
 	EndGlobalSection
 	GlobalSection(ProjectConfigurationPlatforms) = postSolution
 		{3C8A3CF9-A60D-4F21-B866-D291A7AABD4A}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
 		{3C8A3CF9-A60D-4F21-B866-D291A7AABD4A}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{3C8A3CF9-A60D-4F21-B866-D291A7AABD4A}.Debug|ARM64.ActiveCfg = Debug|Any CPU
+		{3C8A3CF9-A60D-4F21-B866-D291A7AABD4A}.Debug|ARM64.Build.0 = Debug|Any CPU
 		{3C8A3CF9-A60D-4F21-B866-D291A7AABD4A}.Debug|x64.ActiveCfg = Debug|Any CPU
 		{3C8A3CF9-A60D-4F21-B866-D291A7AABD4A}.Debug|x64.Build.0 = Debug|Any CPU
 		{3C8A3CF9-A60D-4F21-B866-D291A7AABD4A}.Debug|x86.ActiveCfg = Debug|Any CPU
 		{3C8A3CF9-A60D-4F21-B866-D291A7AABD4A}.Debug|x86.Build.0 = Debug|Any CPU
 		{3C8A3CF9-A60D-4F21-B866-D291A7AABD4A}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{3C8A3CF9-A60D-4F21-B866-D291A7AABD4A}.Release|Any CPU.Build.0 = Release|Any CPU
+		{3C8A3CF9-A60D-4F21-B866-D291A7AABD4A}.Release|ARM64.ActiveCfg = Release|Any CPU
+		{3C8A3CF9-A60D-4F21-B866-D291A7AABD4A}.Release|ARM64.Build.0 = Release|Any CPU
 		{3C8A3CF9-A60D-4F21-B866-D291A7AABD4A}.Release|x64.ActiveCfg = Release|Any CPU
 		{3C8A3CF9-A60D-4F21-B866-D291A7AABD4A}.Release|x64.Build.0 = Release|Any CPU
 		{3C8A3CF9-A60D-4F21-B866-D291A7AABD4A}.Release|x86.ActiveCfg = Release|Any CPU
 		{3C8A3CF9-A60D-4F21-B866-D291A7AABD4A}.Release|x86.Build.0 = Release|Any CPU
 		{7792A94E-D0B4-440D-8BD5-CA1CA548782C}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
 		{7792A94E-D0B4-440D-8BD5-CA1CA548782C}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{7792A94E-D0B4-440D-8BD5-CA1CA548782C}.Debug|ARM64.ActiveCfg = Debug|Any CPU
+		{7792A94E-D0B4-440D-8BD5-CA1CA548782C}.Debug|ARM64.Build.0 = Debug|Any CPU
 		{7792A94E-D0B4-440D-8BD5-CA1CA548782C}.Debug|x64.ActiveCfg = Debug|Any CPU
 		{7792A94E-D0B4-440D-8BD5-CA1CA548782C}.Debug|x64.Build.0 = Debug|Any CPU
 		{7792A94E-D0B4-440D-8BD5-CA1CA548782C}.Debug|x86.ActiveCfg = Debug|Any CPU
 		{7792A94E-D0B4-440D-8BD5-CA1CA548782C}.Debug|x86.Build.0 = Debug|Any CPU
 		{7792A94E-D0B4-440D-8BD5-CA1CA548782C}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{7792A94E-D0B4-440D-8BD5-CA1CA548782C}.Release|Any CPU.Build.0 = Release|Any CPU
+		{7792A94E-D0B4-440D-8BD5-CA1CA548782C}.Release|ARM64.ActiveCfg = Release|Any CPU
+		{7792A94E-D0B4-440D-8BD5-CA1CA548782C}.Release|ARM64.Build.0 = Release|Any CPU
 		{7792A94E-D0B4-440D-8BD5-CA1CA548782C}.Release|x64.ActiveCfg = Release|Any CPU
 		{7792A94E-D0B4-440D-8BD5-CA1CA548782C}.Release|x64.Build.0 = Release|Any CPU
 		{7792A94E-D0B4-440D-8BD5-CA1CA548782C}.Release|x86.ActiveCfg = Release|Any CPU
 		{7792A94E-D0B4-440D-8BD5-CA1CA548782C}.Release|x86.Build.0 = Release|Any CPU
 		{C9666CB2-C9A6-48C8-AB51-D616A48058A7}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
 		{C9666CB2-C9A6-48C8-AB51-D616A48058A7}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{C9666CB2-C9A6-48C8-AB51-D616A48058A7}.Debug|ARM64.ActiveCfg = Debug|Any CPU
+		{C9666CB2-C9A6-48C8-AB51-D616A48058A7}.Debug|ARM64.Build.0 = Debug|Any CPU
 		{C9666CB2-C9A6-48C8-AB51-D616A48058A7}.Debug|x64.ActiveCfg = Debug|Any CPU
 		{C9666CB2-C9A6-48C8-AB51-D616A48058A7}.Debug|x64.Build.0 = Debug|Any CPU
 		{C9666CB2-C9A6-48C8-AB51-D616A48058A7}.Debug|x86.ActiveCfg = Debug|Any CPU
 		{C9666CB2-C9A6-48C8-AB51-D616A48058A7}.Debug|x86.Build.0 = Debug|Any CPU
 		{C9666CB2-C9A6-48C8-AB51-D616A48058A7}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{C9666CB2-C9A6-48C8-AB51-D616A48058A7}.Release|Any CPU.Build.0 = Release|Any CPU
+		{C9666CB2-C9A6-48C8-AB51-D616A48058A7}.Release|ARM64.ActiveCfg = Release|Any CPU
+		{C9666CB2-C9A6-48C8-AB51-D616A48058A7}.Release|ARM64.Build.0 = Release|Any CPU
 		{C9666CB2-C9A6-48C8-AB51-D616A48058A7}.Release|x64.ActiveCfg = Release|Any CPU
 		{C9666CB2-C9A6-48C8-AB51-D616A48058A7}.Release|x64.Build.0 = Release|Any CPU
 		{C9666CB2-C9A6-48C8-AB51-D616A48058A7}.Release|x86.ActiveCfg = Release|Any CPU
 		{C9666CB2-C9A6-48C8-AB51-D616A48058A7}.Release|x86.Build.0 = Release|Any CPU
 		{1AABD2DC-3F81-4301-938B-3EC2EDEF38D4}.Debug|Any CPU.ActiveCfg = Debug|x64
 		{1AABD2DC-3F81-4301-938B-3EC2EDEF38D4}.Debug|Any CPU.Build.0 = Debug|x64
+		{1AABD2DC-3F81-4301-938B-3EC2EDEF38D4}.Debug|ARM64.ActiveCfg = Debug|x64
+		{1AABD2DC-3F81-4301-938B-3EC2EDEF38D4}.Debug|ARM64.Build.0 = Debug|x64
 		{1AABD2DC-3F81-4301-938B-3EC2EDEF38D4}.Debug|x64.ActiveCfg = Debug|x64
 		{1AABD2DC-3F81-4301-938B-3EC2EDEF38D4}.Debug|x64.Build.0 = Debug|x64
 		{1AABD2DC-3F81-4301-938B-3EC2EDEF38D4}.Debug|x86.ActiveCfg = Debug|Win32
 		{1AABD2DC-3F81-4301-938B-3EC2EDEF38D4}.Debug|x86.Build.0 = Debug|Win32
 		{1AABD2DC-3F81-4301-938B-3EC2EDEF38D4}.Release|Any CPU.ActiveCfg = Release|x64
 		{1AABD2DC-3F81-4301-938B-3EC2EDEF38D4}.Release|Any CPU.Build.0 = Release|x64
+		{1AABD2DC-3F81-4301-938B-3EC2EDEF38D4}.Release|ARM64.ActiveCfg = Release|x64
+		{1AABD2DC-3F81-4301-938B-3EC2EDEF38D4}.Release|ARM64.Build.0 = Release|x64
 		{1AABD2DC-3F81-4301-938B-3EC2EDEF38D4}.Release|x64.ActiveCfg = Release|x64
 		{1AABD2DC-3F81-4301-938B-3EC2EDEF38D4}.Release|x64.Build.0 = Release|x64
 		{1AABD2DC-3F81-4301-938B-3EC2EDEF38D4}.Release|x86.ActiveCfg = Release|Win32
 		{1AABD2DC-3F81-4301-938B-3EC2EDEF38D4}.Release|x86.Build.0 = Release|Win32
 		{4E2417E7-FDC3-46D7-B976-84A97B500B74}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
 		{4E2417E7-FDC3-46D7-B976-84A97B500B74}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{4E2417E7-FDC3-46D7-B976-84A97B500B74}.Debug|ARM64.ActiveCfg = Debug|Any CPU
+		{4E2417E7-FDC3-46D7-B976-84A97B500B74}.Debug|ARM64.Build.0 = Debug|Any CPU
 		{4E2417E7-FDC3-46D7-B976-84A97B500B74}.Debug|x64.ActiveCfg = Debug|Any CPU
 		{4E2417E7-FDC3-46D7-B976-84A97B500B74}.Debug|x64.Build.0 = Debug|Any CPU
 		{4E2417E7-FDC3-46D7-B976-84A97B500B74}.Debug|x86.ActiveCfg = Debug|Any CPU
 		{4E2417E7-FDC3-46D7-B976-84A97B500B74}.Debug|x86.Build.0 = Debug|Any CPU
 		{4E2417E7-FDC3-46D7-B976-84A97B500B74}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{4E2417E7-FDC3-46D7-B976-84A97B500B74}.Release|Any CPU.Build.0 = Release|Any CPU
+		{4E2417E7-FDC3-46D7-B976-84A97B500B74}.Release|ARM64.ActiveCfg = Release|Any CPU
+		{4E2417E7-FDC3-46D7-B976-84A97B500B74}.Release|ARM64.Build.0 = Release|Any CPU
 		{4E2417E7-FDC3-46D7-B976-84A97B500B74}.Release|x64.ActiveCfg = Release|Any CPU
 		{4E2417E7-FDC3-46D7-B976-84A97B500B74}.Release|x64.Build.0 = Release|Any CPU
 		{4E2417E7-FDC3-46D7-B976-84A97B500B74}.Release|x86.ActiveCfg = Release|Any CPU

samples/WinConsole32/Program.cs

@@ -11,14 +11,13 @@ namespace WinConsole32
       var libVer = FileVersionInfo.GetVersionInfo(typeof(TwainAppSession).Assembly.Location).ProductVersion;
       Console.WriteLine($"Console sample {(TWPlatform.Is32bit ? " 32bit" : " 64bit")} on NTwain {libVer}");
 
-      MessagePumpThread pump = new MessagePumpThread();
       TwainAppSession session = new TwainAppSession(Environment.ProcessPath!);
 
       session.StateChanged += Session_StateChanged;
       session.SourceDisabled += Session_SourceDisabled1;
       session.Transferred += Session_Transferred;
 
-      var sts = await pump.AttachAsync(session);
+      var sts = await session.OpenDSMAsync();
 
       if (sts.IsSuccess)
       {

samples/WinForm32/Form1.cs

@@ -19,7 +19,6 @@ namespace WinFormSample
   public partial class Form1 : Form
   {
     bool useDiyPump = true;
-    MessagePumpThread pump;
     TwainAppSession twain;
     readonly string saveFolder;
     readonly Stopwatch watch = new();
@@ -36,7 +35,6 @@ namespace WinFormSample
       var libVer = FileVersionInfo.GetVersionInfo(typeof(TwainAppSession).Assembly.Location).ProductVersion;
       Text += $"{(TWPlatform.Is32bit ? " 32bit" : " 64bit")} on NTwain {libVer}";
 
-      pump = new MessagePumpThread();
       TWPlatform.PreferLegacyDSM = false;
 
       twain = new TwainAppSession(Assembly.GetExecutingAssembly().Location);
@@ -87,35 +85,29 @@ namespace WinFormSample
       }
     }
 
-    protected override void OnHandleCreated(EventArgs e)
+    protected override async void OnHandleCreated(EventArgs e)
     {
       base.OnHandleCreated(e);
 
       if (useDiyPump)
       {
-        _ = pump.AttachAsync(twain);
+        var sts = await twain.OpenDSMAsync();
+        Debug.WriteLine($"OpenDSMAsync={sts}");
       }
       else
       {
         var hwnd = this.Handle;
-        var rc = twain.OpenDSM(hwnd, SynchronizationContext.Current!);
+        var sts = twain.OpenDSM(hwnd, SynchronizationContext.Current!);
         twain.AddWinformFilter();
-        Debug.WriteLine($"OpenDSM={rc}");
+        Debug.WriteLine($"OpenDSM={sts}");
       }
     }
 
     protected override void OnClosing(CancelEventArgs e)
     {
-      if (useDiyPump)
+      var finalState = twain.TryStepdown(STATE.S2);
-      {
+      Debug.WriteLine($"Stepdown result state={finalState}");
-        pump.Detatch();
+      twain.RemoveWinformFilter();
-      }
-      else
-      {
-        var finalState = twain.TryStepdown(STATE.S2);
-        Debug.WriteLine($"Stepdown result state={finalState}");
-        twain.RemoveWinformFilter();
-      }
       base.OnClosing(e);
     }
 

src/NTwain/Data/TWAINH_EXTRAS.cs

@@ -1017,7 +1017,7 @@ namespace NTwain.Data
     /// For pointers you'd read it yourself with 
     /// <see cref="ValueReader.ReadTWTYData{TValue}(IntPtr, TWTY, int)"/>.
     /// Unless it's a handle (<see cref="TWTY.HANDLE"/>) to non-twain-strings, then you'd use 
-    /// <see cref="ReadHandleString(IMemoryManager, int)"/>.
+    /// <see cref="ReadHandleString"/>.
     /// </summary>
     /// <typeparam name="TValue"></typeparam>
     /// <returns></returns>

src/NTwain/MessagePumpThread.cs

@@ -12,7 +12,7 @@ namespace NTwain
   /// For use under Windows to host a message pump in non-winform/wpf apps.
   /// This is highly experimental.
   /// </summary>
-  public class MessagePumpThread
+  class MessagePumpThread
   {
     DummyForm? _dummyForm;
     TwainAppSession? _twain;
@@ -70,11 +70,32 @@ namespace NTwain
     /// <summary>
     /// Detatches a previously attached session and stops the thread.
     /// </summary>
-    public void Detatch()
+    public async Task<STS> DetatchAsync()
     {
+      STS sts = default;
       if (_dummyForm != null && _twain != null)
       {
-        _dummyForm.BeginInvoke(_dummyForm.Close);
+        TaskCompletionSource<bool> tcs = new();
+        _dummyForm.BeginInvoke(() =>
+        {
+          sts = _twain.CloseDSMReal();
+          if (sts.IsSuccess)
+          {
+            _twain.RemoveWinformFilter();
+            _dummyForm.Close();
+            _twain = null;
+          }
+        });
+        await tcs.Task;
+      }
+      return sts;
+    }
+
+    public void BringWindowToFront()
+    {
+      if (_dummyForm != null)
+      {
+        _dummyForm.BeginInvoke(_dummyForm.BringToFront);
       }
     }
 
@@ -84,13 +105,6 @@ namespace NTwain
       _dummyForm = new DummyForm();
       _dummyForm.FormClosed += (s, e) =>
       {
-        if (_twain != null)
-        {
-          _twain.TryStepdown(STATE.S4);
-          _twain.RemoveWinformFilter();
-          _twain.CloseDSM();
-          _twain = null;
-        }
         _dummyForm = null;
       };
       Application.Run(_dummyForm);
@@ -104,6 +118,12 @@ namespace NTwain
         ShowInTaskbar = false;
         WindowState = FormWindowState.Minimized;
       }
+
+      protected override void OnShown(EventArgs e)
+      {
+        BringToFront();
+        base.OnShown(e);
+      }
     }
   }
 }

src/NTwain/NTwain.csproj

@@ -21,11 +21,11 @@
   <ItemGroup Condition=" '$(TargetFramework)' != 'net462'">
     <PackageReference Include="System.Text.Encoding.CodePages" Version="7.0.0" />
   </ItemGroup>
-  <ItemGroup>
+  <ItemGroup Condition="'$(Configuration)'!='Release'">
     <None Remove="runtimes\win-x64\native\TWAINDSM.dll" />
     <None Remove="runtimes\win-x86\native\TWAINDSM.dll" />
   </ItemGroup>
-  <ItemGroup>
+  <ItemGroup Condition="'$(Configuration)'!='Release'">
     <Content Include="runtimes\win-x64\native\TWAINDSM.dll">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </Content>

src/NTwain/TwainAppSession.Windows.cs

@@ -35,7 +35,7 @@ namespace NTwain
 
     /// <summary>
     /// Registers this session for use in a WPF UI thread.
-    /// This requires the hwnd used in <see cref="OpenDSM(IntPtr)"/>
+    /// This requires the hwnd used in <see cref="OpenDSM"/>
     /// be a valid WPF window handle.
     /// </summary>
     public void AddWpfHook()

src/NTwain/TwainAppSession.cs

@@ -6,6 +6,7 @@ using System.Diagnostics;
 using System.Runtime.InteropServices;
 using System.Text;
 using System.Threading;
+using System.Threading.Tasks;
 using System.Xml;
 
 namespace NTwain
@@ -99,6 +100,7 @@ namespace NTwain
     internal IntPtr _hwnd;
     internal TW_USERINTERFACE _userInterface; // kept around for disable to use
 #if WINDOWS || NETFRAMEWORK
+    MessagePumpThread? _selfPump;
     TW_EVENT _procEvent; // kept here so the alloc/free only happens once
 #endif
     // test threads a bit
@@ -146,7 +148,6 @@ namespace NTwain
         {
           // this will end the bg thread
           _xferReady.Dispose();
-
           //_bgPendingMsgs.CompleteAdding();
         }
 #if WINDOWS || NETFRAMEWORK
@@ -170,6 +171,45 @@ namespace NTwain
       GC.SuppressFinalize(this);
     }
 
+#if WINDOWS || NETFRAMEWORK
+    /// <summary>
+    /// Loads and opens the TWAIN data source manager in a self-hosted message queue thread.
+    /// Highly experimental and only use if necessary. Must close with <see cref="CloseDSMAsync"/>
+    /// if used.
+    /// </summary>
+    /// <returns></returns>
+    public async Task<STS> OpenDSMAsync()
+    {
+      if (_selfPump == null)
+      {
+        var pump = new MessagePumpThread();
+        var sts = await pump.AttachAsync(this);
+        if (sts.IsSuccess)
+        {
+          _selfPump = pump;
+        }
+        return sts;
+      }
+      return new STS { RC = TWRC.FAILURE, STATUS = new TW_STATUS { ConditionCode = TWCC.SEQERROR } };
+    }
+
+    /// <summary>
+    /// Closes the TWAIN data source manager if opened with <see cref="OpenDSMAsync"/>.
+    /// </summary>
+    /// <returns></returns>
+    /// <exception cref="InvalidOperationException"></exception>
+    public async Task<STS> CloseDSMAsync()
+    {
+      if (_selfPump == null) throw new InvalidOperationException($"Cannot close if not opened with {nameof(OpenDSMAsync)}().");
+
+      var sts = await _selfPump.DetatchAsync();
+      if (sts.IsSuccess)
+      {
+        _selfPump = null;
+      }
+      return sts;
+    }
+#endif
 
     /// <summary>
     /// Loads and opens the TWAIN data source manager.
@@ -210,8 +250,21 @@ namespace NTwain
     /// Closes the TWAIN data source manager.
     /// </summary>
     /// <returns></returns>
+    /// <exception cref="InvalidOperationException"></exception>
     public STS CloseDSM()
     {
+#if WINDOWS || NETFRAMEWORK
+      if (_selfPump != null) throw new InvalidOperationException($"Cannot close if opened with {nameof(OpenDSMAsync)}().");
+#endif
+      return CloseDSMReal();
+    }
+
+    /// <summary>
+    /// Closes the TWAIN data source manager.
+    /// </summary>
+    /// <returns></returns>
+    internal STS CloseDSMReal()
+    {
       var rc = DGControl.Parent.CloseDSM(ref _appIdentity, _hwnd);
       if (rc == TWRC.SUCCESS)
       {
@@ -312,7 +365,29 @@ namespace NTwain
             CloseSource();
             break;
           case STATE.S3:
+#if WINDOWS || NETFRAMEWORK
+            if (_selfPump != null)
+            {
+              try
+              {
+                _ = CloseDSMAsync();
+              }
+              catch (InvalidOperationException) { }
+            }
+            else
+            {
+              CloseDSM();
+            }
+#else
             CloseDSM();
+#endif
+            break;
+          case STATE.S2:
+            // can't really go lower
+            if (targetState < STATE.S2)
+            {
+              return State;
+            }
             break;
         }
         if (oldState == State)