Updated string read and fixed sample.

NTwain/Data/CapReadOut.cs

@@ -266,16 +266,16 @@ namespace NTwain.Data
                     frame.Bottom = (TWFix32)ReadValue(baseAddr, ref offset, ItemType.Fix32);
                     return frame; // no need to update offset again after reading fix32
                 case ItemType.String128:
-                    val = ReadString(baseAddr, offset, 128);
+                    val = ReadString(baseAddr, offset, TwainConst.String128 - 2);
                     break;
                 case ItemType.String255:
-                    val = ReadString(baseAddr, offset, 255);
+                    val = ReadString(baseAddr, offset, TwainConst.String255 - 1);
                     break;
                 case ItemType.String32:
-                    val = ReadString(baseAddr, offset, 32);
+                    val = ReadString(baseAddr, offset, TwainConst.String32 - 2);
                     break;
                 case ItemType.String64:
-                    val = ReadString(baseAddr, offset, 64);
+                    val = ReadString(baseAddr, offset, TwainConst.String64 - 2);
                     break;
                 case ItemType.Handle:
                     val = new IntPtr(baseAddr.ToInt64() + offset);
@@ -294,16 +294,21 @@ namespace NTwain.Data
         /// <returns></returns>
         static string ReadString(IntPtr baseAddr, int offset, int maxLength)
         {
-            // todo: add support for other platform
+            // does this work cross-platform?
-
+            var val = Marshal.PtrToStringAnsi(new IntPtr(baseAddr.ToInt64() + offset));
-            var sb = new StringBuilder(maxLength);
+            if (val.Length > maxLength)
-            byte bt;
-            while (sb.Length < maxLength &&
-                (bt = Marshal.ReadByte(baseAddr, offset++)) != 0)
             {
-                sb.Append((char)bt);
+                // bad source, whatever
             }
-            return sb.ToString();
+            return val;
+            //var sb = new StringBuilder(maxLength);
+            //byte bt;
+            //while (sb.Length < maxLength &&
+            //    (bt = Marshal.ReadByte(baseAddr, offset++)) != 0)
+            //{
+            //    sb.Append((char)bt);
+            //}
+            //return sb.ToString();
         }
 
 

NTwain/DataTransferredEventArgs.cs

@@ -1,4 +1,5 @@
-using System;
+using NTwain.Data;
+using System;
 
 namespace NTwain
 {
@@ -8,30 +9,36 @@ namespace NTwain
 	public class DataTransferredEventArgs : EventArgs
 	{
 		/// <summary>
-		/// Initializes a new instance of the <see cref="DataTransferredEventArgs" /> class.
+		/// Gets pointer to the complete data if the transfer was native.
-		/// </summary>
-		/// <param name="data">The data pointer.</param>
-		/// <param name="filePath">The file.</param>
-		internal DataTransferredEventArgs(IntPtr data, string filePath)
-		{
-			Data = data;
-			FilePath = filePath;
-		}
-		/// <summary>
-		/// Gets pointer to the image data if applicable.
 		/// The data will be freed once the event handler ends
-		/// so consumers must complete whatever processing
+		/// so consumers must complete whatever processing before then.
-		/// required by then.
+        /// For image type this data is DIB (Windows), PICT (old Mac), and TIFF (Linux/OSX).
 		/// </summary>
 		/// <value>The data pointer.</value>
-		public IntPtr Data { get; private set; }
+		public IntPtr NativeData { get; internal set; }
 
 		/// <summary>
-		/// Gets the filepath to the transferrerd data if applicable.
+		/// Gets the file path to the complete data if the transfer was file or memory-file.
 		/// </summary>
 		/// <value>
 		/// The file.
 		/// </value>
-		public string FilePath { get; private set; }
+        public string FilePath { get; internal set; }
+
+        /// <summary>
+        /// Gets the memory data if the transfer was memory.
+        /// </summary>
+        /// <value>
+        /// The memory data.
+        /// </value>
+        public byte[] MemData { get; internal set; }
+
+        /// <summary>
+        /// Gets the final image information if applicable.
+        /// </summary>
+        /// <value>
+        /// The final image information.
+        /// </value>
+        public TWImageInfo FinalImageInfo { get; internal set; }
 	}
 }

NTwain/NTwain.nuspec

@@ -11,7 +11,7 @@
     <!--<iconUrl>http://ICON_URL_HERE_OR_DELETE_THIS_LINE</iconUrl>-->
     <requireLicenseAcceptance>false</requireLicenseAcceptance>
     <description>$description$</description>
-    <releaseNotes>V0.9 release is updated for TWAIN 2.3 and contains some refactoring that may require updating existing code.</releaseNotes>
+    <releaseNotes>This release supports TWAIN 2.3.</releaseNotes>
     <copyright>$copyright$</copyright>
     <tags>twain scan</tags>
   </metadata>

NTwain/TransferReadyEventArgs.cs

@@ -39,7 +39,7 @@ namespace NTwain
 
         /// <summary>
         /// Gets the tentative image information for the current transfer if applicable.
-        /// This may differ from the final image depending on the transfer mode used.
+        /// This may differ from the final image depending on the transfer mode used (mostly when doing mem xfer).
         /// </summary>
         /// <value>
         /// The image info.

NTwain/Triplets/DGImage/DGImage.ExtImageInfo.cs

@@ -11,9 +11,10 @@ namespace NTwain.Triplets
 	{
 		internal ExtImageInfo(ITwainStateInternal session) : base(session) { }
 
-		public ReturnCode Get(TWExtImageInfo info)
+		public ReturnCode Get(out TWExtImageInfo info)
 		{
 			Session.VerifyState(7, 7, DataGroups.Image, DataArgumentType.ExtImageInfo, Message.Get);
+            info = new TWExtImageInfo();
             return PInvoke.DsmEntry(Session.GetAppId(), Session.SourceId, Message.Get, info);
 		}
 	}

NTwain/Triplets/PInvoke.cs

@@ -31,6 +31,10 @@ namespace NTwain.Triplets
                 File.Exists(path);
         }
 
+        static readonly bool IsWin = Environment.OSVersion.Platform == PlatformID.Win32NT;
+        static readonly bool IsOSX = Environment.OSVersion.Platform == PlatformID.MacOSX;
+        static readonly bool IsLinux = Environment.OSVersion.Platform == PlatformID.Unix;
+
         // define sig for each different data type since "object" doesn't work
 
         #region wrapped calls

NTwain/TwainSession.cs

@@ -37,6 +37,7 @@ namespace NTwain
         object _callbackObj; // kept around so it doesn't get gc'ed
         TWUserInterface _twui;
 
+        static readonly CapabilityId[] _emptyCapList = new CapabilityId[0];
 
         private IList<CapabilityId> _supportedCaps;
         /// <summary>
@@ -53,7 +54,7 @@ namespace NTwain
                 {
                     _supportedCaps = this.GetCapabilities();
                 }
-                return _supportedCaps ?? new CapabilityId[0];
+                return _supportedCaps ?? _emptyCapList;
             }
             private set
             {
@@ -289,6 +290,7 @@ namespace NTwain
             if (rc == ReturnCode.Success)
             {
                 _callbackObj = null;
+                SupportedCaps = null;
             }
             return rc;
         }
@@ -776,7 +778,7 @@ namespace NTwain
                     {
                         lockedPtr = MemoryManager.Instance.Lock(dataPtr);
                     }
-                    OnDataTransferred(new DataTransferredEventArgs(lockedPtr, null));
+                    OnDataTransferred(new DataTransferredEventArgs { NativeData = lockedPtr });
                 }
             }
             finally
@@ -808,7 +810,7 @@ namespace NTwain
             var xrc = DGAudio.AudioFileXfer.Get();
             if (xrc == ReturnCode.XferDone)
             {
-                OnDataTransferred(new DataTransferredEventArgs(IntPtr.Zero, filePath));
+                OnDataTransferred(new DataTransferredEventArgs { FilePath = filePath });
             }
         }
 
@@ -826,11 +828,16 @@ namespace NTwain
                 if (xrc == ReturnCode.XferDone)
                 {
                     State = 7;
+                    TWImageInfo imgInfo;
+                    if (DGImage.ImageInfo.Get(out imgInfo) != ReturnCode.Success)
+                    {
+                        imgInfo = null;
+                    }
                     if (dataPtr != IntPtr.Zero)
                     {
                         lockedPtr = MemoryManager.Instance.Lock(dataPtr);
                     }
-                    OnDataTransferred(new DataTransferredEventArgs(lockedPtr, null));
+                    OnDataTransferred(new DataTransferredEventArgs { NativeData = lockedPtr, FinalImageInfo = imgInfo });
                 }
             }
             finally
@@ -862,13 +869,93 @@ namespace NTwain
             var xrc = DGImage.ImageFileXfer.Get();
             if (xrc == ReturnCode.XferDone)
             {
-                OnDataTransferred(new DataTransferredEventArgs(IntPtr.Zero, filePath));
+                TWImageInfo imgInfo;
+                if (DGImage.ImageInfo.Get(out imgInfo) != ReturnCode.Success)
+                {
+                    imgInfo = null;
+                }
+                OnDataTransferred(new DataTransferredEventArgs { FilePath = filePath, FinalImageInfo = imgInfo });
             }
         }
 
         private void DoImageMemoryXfer()
         {
             throw new NotImplementedException();
+
+            TWSetupMemXfer memInfo;
+            if (DGControl.SetupMemXfer.Get(out memInfo) == ReturnCode.Success)
+            {
+                TWImageMemXfer xferInfo = new TWImageMemXfer();
+                try
+                {
+                    xferInfo.Memory = new TWMemory
+                    {
+                        Flags = MemoryFlags.AppOwns | MemoryFlags.Pointer,
+                        Length = memInfo.Preferred,
+                        TheMem = MemoryManager.Instance.Allocate(memInfo.Preferred)
+                    };
+
+                    var xrc = ReturnCode.Success;
+                    do
+                    {
+                        xrc = DGImage.ImageMemFileXfer.Get(xferInfo);
+
+                        if (xrc == ReturnCode.Success ||
+                            xrc == ReturnCode.XferDone)
+                        {
+                            State = 7;
+                            byte[] buffer = new byte[(int)xferInfo.BytesWritten];
+                            // todo: need lock before use?
+                            IntPtr lockPtr = IntPtr.Zero;
+                            try
+                            {
+                                lockPtr = MemoryManager.Instance.Lock(xferInfo.Memory.TheMem);
+                                Marshal.Copy(lockPtr, buffer, 0, buffer.Length);
+                            }
+                            finally
+                            {
+                                if (lockPtr != IntPtr.Zero)
+                                {
+                                    MemoryManager.Instance.Unlock(lockPtr);
+                                }
+                            }
+                            // now what?
+
+                        }
+                    } while (xrc == ReturnCode.Success);
+
+                    if (xrc == ReturnCode.XferDone)
+                    {
+                        TWImageInfo imgInfo;
+                        //TWExtImageInfo extInfo;
+                        //if (SupportedCaps.Contains(CapabilityId.ICapExtImageInfo))
+                        //{
+                        //    if (DGImage.ExtImageInfo.Get(out extInfo) != ReturnCode.Success)
+                        //    {
+                        //        extInfo = null;
+                        //    }
+                        //}
+                        if (DGImage.ImageInfo.Get(out imgInfo) == ReturnCode.Success)
+                        {
+                            //OnDataTransferred(new DataTransferredEventArgs(IntPtr.Zero, null));
+                        }
+                        else
+                        {
+                            Trace.TraceError("Failed to get image info after ImageMemXfer.");
+                            imgInfo = null;
+                        }
+                    }
+                }
+                finally
+                {
+                    State = 6;
+                    if (xferInfo.Memory.TheMem != IntPtr.Zero)
+                    {
+                        MemoryManager.Instance.Free(xferInfo.Memory.TheMem);
+                    }
+                }
+
+            }
         }
 
         private void DoImageMemoryFileXfer()
@@ -886,6 +973,7 @@ namespace NTwain
                 {
                     xferInfo.Memory = new TWMemory
                     {
+                        Flags = MemoryFlags.AppOwns | MemoryFlags.Pointer,
                         Length = memInfo.Preferred,
                         TheMem = MemoryManager.Instance.Allocate(memInfo.Preferred)
                     };
@@ -900,8 +988,22 @@ namespace NTwain
                             if (xrc == ReturnCode.Success ||
                                 xrc == ReturnCode.XferDone)
                             {
+                                State = 7;
                                 byte[] buffer = new byte[(int)xferInfo.BytesWritten];
-                                Marshal.Copy(xferInfo.Memory.TheMem, buffer, 0, buffer.Length);
+                                // todo: need lock before use?
+                                IntPtr lockPtr = IntPtr.Zero;
+                                try
+                                {
+                                    lockPtr = MemoryManager.Instance.Lock(xferInfo.Memory.TheMem);
+                                    Marshal.Copy(lockPtr, buffer, 0, buffer.Length);
+                                }
+                                finally
+                                {
+                                    if (lockPtr != IntPtr.Zero)
+                                    {
+                                        MemoryManager.Instance.Unlock(lockPtr);
+                                    }
+                                }
                                 outStream.Write(buffer, 0, buffer.Length);
                             }
                         } while (xrc == ReturnCode.Success);
@@ -962,6 +1064,7 @@ namespace NTwain
                 }
                 finally
                 {
+                    State = 6;
                     if (xferInfo.Memory.TheMem != IntPtr.Zero)
                     {
                         MemoryManager.Instance.Free(xferInfo.Memory.TheMem);
@@ -974,7 +1077,12 @@ namespace NTwain
 
                 if (File.Exists(finalFile))
                 {
-                    OnDataTransferred(new DataTransferredEventArgs(IntPtr.Zero, finalFile));
+                    TWImageInfo imgInfo;
+                    if (DGImage.ImageInfo.Get(out imgInfo) != ReturnCode.Success)
+                    {
+                        imgInfo = null;
+                    }
+                    OnDataTransferred(new DataTransferredEventArgs { FilePath = finalFile, FinalImageInfo = imgInfo });
                 }
             }
         }

NTwain/TwainSessionOld.cs

@@ -120,7 +120,7 @@ namespace NTwain
                             {
                                 lockedPtr = MemoryManager.Instance.Lock(dataPtr);
                             }
-                            OnDataTransferred(new DataTransferredEventArgs(lockedPtr, file));
+                            OnDataTransferred(new DataTransferredEventArgs { NativeData = lockedPtr, FilePath = file });
                         }
                         //}
                         //else if (group == DataGroups.Audio)

Tests/NTwain.Tests/DataTransferredEventArgsTests.cs

@@ -1,26 +0,0 @@
-using NTwain;
-using Microsoft.VisualStudio.TestTools.UnitTesting;
-using System;
-using NTwain.Values;
-using System.Runtime.Serialization;
-
-namespace NTwain.Tests
-{
-    [TestClass]
-    public class DataTransferredEventArgsTests
-    {
-        [TestMethod]
-        public void Constructor_Sets_Correct_Properties()
-        {
-            // just some non-default values to test
-            IntPtr data = new IntPtr(10);
-            string file = "THIS IS A TEST.";
-
-            DataTransferredEventArgs target = new DataTransferredEventArgs(data, file);
-
-            Assert.AreEqual(data, target.Data, "Data mismatch.");
-            Assert.AreEqual(file, target.FilePath, "File mismatch.");
-        }
-
-    }
-}

Tests/NTwain.Tests/NTwain.Tests.csproj

@@ -54,9 +54,6 @@
     </CodeAnalysisDependentAssemblyPaths>
   </ItemGroup>
   <ItemGroup>
-    <Compile Include="DataTransferredEventArgsTests.cs">
-      <SubType>Code</SubType>
-    </Compile>
     <Compile Include="Data\TWIdentityTest.cs">
       <SubType>Code</SubType>
     </Compile>

Tests/Tester.Console/Program.cs

@@ -93,7 +93,7 @@ namespace Tester
 
         static void twain_DataTransferred(object sender, DataTransferredEventArgs e)
         {
-            if (e.Data != IntPtr.Zero)
+            if (e.NativeData != IntPtr.Zero)
             {
                 Console.WriteLine("Got twain data on thread {0}", Thread.CurrentThread.ManagedThreadId);
             }

Tests/Tester.WPF/TwainVM.cs

@@ -63,9 +63,9 @@ namespace Tester.WPF
 
         protected override void OnDataTransferred(DataTransferredEventArgs e)
         {
-            if (e.Data != IntPtr.Zero)
+            if (e.NativeData != IntPtr.Zero)
             {
-                Image = e.Data.GetWPFBitmap();
+                Image = e.NativeData.GetWPFBitmap();
             }
             else if (!string.IsNullOrEmpty(e.FilePath))
             {

Tests/Tester.Winform/TestForm.cs

@@ -69,10 +69,10 @@ namespace Tester.Winform
                     pictureBox1.Image.Dispose();
                     pictureBox1.Image = null;
                 }
-                if (e.Data != IntPtr.Zero)
+                if (e.NativeData != IntPtr.Zero)
                 {
                     //_ptrTest = e.Data;
-                    var img = e.Data.GetDrawingBitmap();
+                    var img = e.NativeData.GetDrawingBitmap();
                     if (img != null)
                         pictureBox1.Image = img;
                 }
@@ -284,7 +284,7 @@ namespace Tester.Winform
         {
             var list = _twain.CapGetSupportedSizes();
             comboSize.DataSource = list;
-            var cur = _twain.GetCurrentCap<SupportedSize>(CapabilityId.ICapSupportedSizes);
+            var cur = _twain.GetCurrentCap(CapabilityId.ICapSupportedSizes).ConvertToEnum<SupportedSize>();
             if (list.Contains(cur))
             {
                 comboSize.SelectedItem = cur;
@@ -293,7 +293,7 @@ namespace Tester.Winform
 
         private void LoadDuplex()
         {
-            ckDuplex.Checked = _twain.GetCurrentCap<uint>(CapabilityId.CapDuplexEnabled) != 0;
+            ckDuplex.Checked = _twain.GetCurrentCap(CapabilityId.CapDuplexEnabled).ConvertToEnum<uint>() != 0;
         }
 
         private void LoadDPI()
@@ -301,7 +301,7 @@ namespace Tester.Winform
             // only allow dpi of certain values for those source that lists everything
             var list = _twain.CapGetDPIs().Where(dpi => (dpi % 50) == 0).ToList();
             comboDPI.DataSource = list;
-            var cur = _twain.GetCurrentCap<int>(CapabilityId.ICapXResolution);
+            var cur = (TWFix32)_twain.GetCurrentCap(CapabilityId.ICapXResolution);
             if (list.Contains(cur))
             {
                 comboDPI.SelectedItem = cur;
@@ -312,7 +312,7 @@ namespace Tester.Winform
         {
             var list = _twain.CapGetPixelTypes();
             comboDepth.DataSource = list;
-            var cur = _twain.GetCurrentCap<PixelType>(CapabilityId.ICapPixelType);
+            var cur = _twain.GetCurrentCap(CapabilityId.ICapPixelType).ConvertToEnum<PixelType>();
             if (list.Contains(cur))
             {
                 comboDepth.SelectedItem = cur;