Lift char-block detachment onto the reader interface

src/LogExpert.Core/Classes/Log/LogfileReader.cs

@@ -909,6 +909,11 @@ public ILogLineMemory[] GetLogLineMemories (int startLine, int count)
                     var availableInBuffer = logBufferEntry.Buffer.LineCount - bufferOffset;
                     var toCopy = Math.Min(count - filled, availableInBuffer);
 
+                    if (bufferOffset < 0 || toCopy <= 0)
+                    {
+                        break;
+                    }
+
                     for (var i = 0; i < toCopy; i++)
                     {
                         result[filled + i] = logBufferEntry.Buffer.GetLineMemoryOfBlock(bufferOffset + i);
@@ -1256,16 +1261,9 @@ private void ReadToBufferList (ILogFileInfo logFileInfo, long filePos, int start
 
                         logBuffer.Size = filePos - logBuffer.StartPos;
 
-                        // Detach char blocks from the reader's allocator and attach to the completed buffer.
+                        // Detach char blocks from the reader and attach to the completed buffer.
                         // Must happen before Monitor.Exit so the buffer is still exclusively owned.
-                        if (reader is PositionAwareStreamReaderSystem systemDetachBlockReader)
-                        {
-                            logBuffer.AttachCharBlocks(systemDetachBlockReader.BlockAllocator.DetachBlocks());
-                        }
-                        else if (reader is PositionAwareStreamReaderDirect directReader)
-                        {
-                            logBuffer.AttachCharBlocks(directReader.DetachBlocks());
-                        }
+                        logBuffer.AttachCharBlocks(reader.DetachCharBlocks());
 
                         Monitor.Exit(logBuffer);
                         try
@@ -1297,14 +1295,7 @@ private void ReadToBufferList (ILogFileInfo logFileInfo, long filePos, int start
                 logBuffer.Size = filePos - logBuffer.StartPos;
 
                 // Attach remaining blocks to the final buffer
-                if (reader is PositionAwareStreamReaderSystem systemDetachBlockReader2)
-                {
-                    logBuffer.AttachCharBlocks(systemDetachBlockReader2.BlockAllocator.DetachBlocks());
-                }
-                else if (reader is PositionAwareStreamReaderDirect directReader)
-                {
-                    logBuffer.AttachCharBlocks(directReader.DetachBlocks());
-                }
+                logBuffer.AttachCharBlocks(reader.DetachCharBlocks());
             }
             finally
             {
@@ -1427,14 +1418,7 @@ private void ReReadBuffer (LogBuffer logBuffer)
                     }
 
                     // Attach char blocks from the reader to the re-read buffer
-                    if (reader is PositionAwareStreamReaderSystem systemReader)
-                    {
-                        logBuffer.AttachCharBlocks(systemReader.BlockAllocator.DetachBlocks());
-                    }
-                    else if (reader is PositionAwareStreamReaderDirect directReader)
-                    {
-                        logBuffer.AttachCharBlocks(directReader.DetachBlocks());
-                    }
+                    logBuffer.AttachCharBlocks(reader.DetachCharBlocks());
 
                     if (maxLinesCount != logBuffer.LineCount)
                     {

src/LogExpert.Core/Classes/Log/Streamreaders/PositionAwareStreamReaderDirect.cs

@@ -1,7 +1,6 @@
 using System.Buffers;
 using System.Text;
 
-using LogExpert.Core.Classes.Log.Buffers;
 using LogExpert.Core.Entities;
 using LogExpert.Core.Interfaces;
 
@@ -156,17 +155,11 @@ public void ReturnMemory (ReadOnlyMemory<char> memory)
         // Bulk return via DetachBlocks()/Dispose(). Individual return not needed.
     }
 
-    /// <summary>
-    /// Gets the block allocator for compatibility with the DetachBlocks pattern.
-    /// This reader manages its own blocks directly rather than through CharBlockAllocator.
-    /// </summary>
-    public CharBlockAllocator? BlockAllocator => null;
-
     /// <summary>
     /// Detaches completed blocks (fully scanned) for transfer to the LogBuffer.
     /// The current _readBlock (partially scanned) stays with the reader.
     /// </summary>
-    public List<char[]> DetachBlocks ()
+    public List<char[]> DetachCharBlocks ()
     {
         // Nothing to detach: no completed blocks and no lines were scanned from the current block.
         if (_completedBlocks.Count == 0 && _scanOffset == 0)

src/LogExpert.Core/Classes/Log/Streamreaders/PositionAwareStreamReaderLegacy.cs

@@ -19,10 +19,10 @@ public class PositionAwareStreamReaderLegacy (Stream stream, EncodingOptions enc
 
     #region Properties
 
-    public CharBlockAllocator BlockAllocator
+    private CharBlockAllocator BlockAllocator
     {
         get => field ??= new CharBlockAllocator();
-        private set;
+        set;
     }
 
     #endregion
@@ -47,7 +47,20 @@ public bool TryReadLine (out ReadOnlyMemory<char> lineMemory)
 
     public void ReturnMemory (ReadOnlyMemory<char> memory)
     {
-        // Bulk return via BlockAllocator.DetachBlocks() when the LogBuffer is evicted.
+        // Bulk return via DetachCharBlocks() when the LogBuffer is evicted, or Dispose().
+    }
+
+    public List<char[]> DetachCharBlocks () => BlockAllocator.DetachBlocks();
+
+    protected override void Dispose (bool disposing)
+    {
+        if (disposing)
+        {
+            BlockAllocator?.Dispose();
+            BlockAllocator = null;
+        }
+
+        base.Dispose(disposing);
     }
 
     public override string ReadLine ()

src/LogExpert.Core/Classes/Log/Streamreaders/PositionAwareStreamReaderSystem.cs

@@ -36,13 +36,13 @@ public PositionAwareStreamReaderSystem (Stream stream, EncodingOptions encodingO
     #region Properties
 
     /// <summary>
-    /// Gets or creates the block allocator used by this reader instance.
-    /// The caller can detach the blocks after reading a buffer's worth of lines.
+    /// The block allocator used by this reader instance. Blocks are handed to the owning buffer via
+    /// <see cref="DetachCharBlocks"/>; ownership of the allocator does not cross the reader seam.
     /// </summary>
-    public CharBlockAllocator BlockAllocator
+    private CharBlockAllocator BlockAllocator
     {
         get => field ??= new CharBlockAllocator();
-        private set;
+        set;
     }
 
     #endregion
@@ -112,10 +112,12 @@ public bool TryReadLine (out ReadOnlyMemory<char> lineMemory)
     /// </summary>
     public void ReturnMemory (ReadOnlyMemory<char> memory)
     {
-        // Bulk return via BlockAllocator.DetachBlocks() or Dispose().
+        // Bulk return via DetachCharBlocks() or Dispose().
         // Individual per-line return is not needed with block-based allocation.
     }
 
+    public List<char[]> DetachCharBlocks () => BlockAllocator.DetachBlocks();
+
     #endregion
 
     #region Private Methods

src/LogExpert.Core/Interfaces/ILogStreamReaderMemory.cs

@@ -36,4 +36,19 @@ public interface ILogStreamReaderMemory : ILogStreamReader
     /// call this method multiple times for the same memory, but only the first call will have an effect.
     /// </remarks>
     void ReturnMemory (ReadOnlyMemory<char> memory);
+
+    /// <summary>
+    /// Detaches the completed character blocks that back the <see cref="ReadOnlyMemory{Char}"/> slices handed out by
+    /// <see cref="TryReadLine"/>, transferring their ownership to the caller (the <c>LogBuffer</c> that owns those
+    /// lines).
+    /// </summary>
+    /// <returns>
+    /// The list of blocks the reader has filled. The caller owns them until every slice into them is released, at
+    /// which point they are returned to the shared pool. Readers that have nothing to hand over return an empty list.
+    /// </returns>
+    /// <remarks>
+    /// Call this after a buffer's worth of lines has been read and before the reader continues filling the next
+    /// buffer. The reader retains any partially-scanned block so reading can continue seamlessly.
+    /// </remarks>
+    List<char[]> DetachCharBlocks ();
 }

src/LogExpert.Tests/StreamReaderTests/LogStreamReaderTest.cs

@@ -178,7 +178,7 @@ public void TryReadLine_ReturnsBlockBackedMemory_NotStringBacked ()
     }
 
     [Test]
-    public void TryReadLine_BlockAllocatorHasBlocks_AfterReading ()
+    public void TryReadLine_DetachCharBlocks_ReturnsFilledBlocks_AfterReading ()
     {
         var text = "Line 1\nLine 2\nLine 3\n";
         using var stream = new MemoryStream(Encoding.UTF8.GetBytes(text));
@@ -189,12 +189,12 @@ public void TryReadLine_BlockAllocatorHasBlocks_AfterReading ()
             // Intentionally empty: consume all lines to advance reader state.
         }
 
-        // The allocator should have at least 1 block
-        Assert.That(reader.BlockAllocator.BlockCount, Is.GreaterThanOrEqualTo(1));
+        // Reading rented at least one block, exposed only through the seam.
+        Assert.That(reader.DetachCharBlocks(), Has.Count.GreaterThanOrEqualTo(1));
     }
 
     [Test]
-    public void TryReadLine_DetachBlocks_TransfersOwnership ()
+    public void TryReadLine_DetachCharBlocks_TransfersOwnership ()
     {
         var text = "Line 1\nLine 2\nLine 3\n";
         using var stream = new MemoryStream(Encoding.UTF8.GetBytes(text));
@@ -205,11 +205,8 @@ public void TryReadLine_DetachBlocks_TransfersOwnership ()
             // Intentionally empty: consume all lines to advance reader state.
         }
 
-        var blocks = reader.BlockAllocator.DetachBlocks();
+        var blocks = reader.DetachCharBlocks();
         Assert.That(blocks, Has.Count.GreaterThanOrEqualTo(1));
-
-        // After detach, allocator should have a fresh block
-        Assert.That(reader.BlockAllocator.BlockCount, Is.EqualTo(1));
     }
 
     [Test]

src/LogExpert.Tests/StreamReaderTests/PositionAwareStreamReaderDirectTests.cs

@@ -258,10 +258,10 @@ public void ContentParity_LargeFile ()
 
     #endregion
 
-    #region DetachBlocks
+    #region DetachCharBlocks
 
     [Test]
-    public void DetachBlocks_ReturnsCompletedBlocks ()
+    public void DetachCharBlocks_ReturnsCompletedBlocks ()
     {
         // Create enough content to fill multiple blocks
         var sb = new StringBuilder();
@@ -279,11 +279,11 @@ public void DetachBlocks_ReturnsCompletedBlocks ()
             // Intentionally empty: consume all lines to advance reader state.
         }
 
-        var blocks = reader.DetachBlocks();
+        var blocks = reader.DetachCharBlocks();
         Assert.That(blocks.Count, Is.GreaterThan(0), "Should have completed blocks to detach");
 
         // Second detach should be empty
-        var blocks2 = reader.DetachBlocks();
+        var blocks2 = reader.DetachCharBlocks();
         Assert.That(blocks2.Count, Is.EqualTo(0));
     }
 
@@ -506,7 +506,7 @@ public void TryReadLine_LineLongerThanBlockSize_WithMaxLineLengthTruncation ()
     }
 
     [Test]
-    public void TryReadLine_LineLongerThanBlockSize_DetachBlocksAfterEachLine ()
+    public void TryReadLine_LineLongerThanBlockSize_DetachCharBlocksAfterEachLine ()
     {
         RunWithTimeout(() =>
         {
@@ -521,12 +521,12 @@ public void TryReadLine_LineLongerThanBlockSize_DetachBlocksAfterEachLine ()
 
             Assert.That(reader.TryReadLine(out var line1), Is.True);
             Assert.That(line1.Span.ToString(), Is.EqualTo("line1"));
-            var blocks1 = reader.DetachBlocks();
+            var blocks1 = reader.DetachCharBlocks();
             Assert.That(blocks1.Count, Is.GreaterThan(0));
 
             Assert.That(reader.TryReadLine(out var line2), Is.True);
             Assert.That(line2.Length, Is.EqualTo(lineLength));
-            var blocks2 = reader.DetachBlocks();
+            var blocks2 = reader.DetachCharBlocks();
             Assert.That(blocks2.Count, Is.GreaterThan(0));
 
             Assert.That(reader.TryReadLine(out var line3), Is.True);
@@ -537,7 +537,7 @@ public void TryReadLine_LineLongerThanBlockSize_DetachBlocksAfterEachLine ()
     }
 
     [Test]
-    public void TryReadLine_LineLongerThanBlockSize_DetachBlocksWithLargeTail ()
+    public void TryReadLine_LineLongerThanBlockSize_DetachCharBlocksWithLargeTail ()
     {
         RunWithTimeout(() =>
         {
@@ -573,14 +573,14 @@ public void TryReadLine_LineLongerThanBlockSize_DetachBlocksWithLargeTail ()
             // Read and detach the prefix (resets reader to fresh BLOCK_SIZE buffer)
             Assert.That(reader.TryReadLine(out var line1), Is.True);
             Assert.That(line1.Span.ToString(), Is.EqualTo("prefix"));
-            _ = reader.DetachBlocks();
+            _ = reader.DetachCharBlocks();
 
             // Read the long line — this grows the buffer to 131072
             Assert.That(reader.TryReadLine(out var line2), Is.True);
             Assert.That(line2.Length, Is.EqualTo(longLineLength));
 
             // THIS IS THE CRITICAL CALL: DetachBlocks must handle tail > BLOCK_SIZE
-            var blocks = reader.DetachBlocks();
+            var blocks = reader.DetachCharBlocks();
             Assert.That(blocks.Count, Is.GreaterThan(0));
 
             // Verify we can still read subsequent lines correctly

src/PluginRegistry/PluginHashGenerator.Generated.cs

@@ -10,35 +10,35 @@ public static partial class PluginValidator
 {
     /// <summary>
     /// Gets pre-calculated SHA256 hashes for built-in plugins.
-    /// Generated: 2026-06-25 12:45:02 UTC
+    /// Generated: 2026-06-25 14:06:29 UTC
     /// Configuration: Release
     /// Plugin count: 21
     /// </summary>
     public static Dictionary<string, string> GetBuiltInPluginHashes()
     {
         return new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase)
         {
-                         ["AutoColumnizer.dll"] = "97CB14C8E6F7A714A74E92152CD947B2DF26742AC4C6F1550366B5C2586FB7F8",
+                         ["AutoColumnizer.dll"] = "E6BBCB994A140BC595E67D19A7E6E9975469718628C5BA8E423DCF13E076FA81",
             ["BouncyCastle.Cryptography.dll"] = "E5EEAF6D263C493619982FD3638E6135077311D08C961E1FE128F9107D29EBC6",
             ["BouncyCastle.Cryptography.dll (x86)"] = "E5EEAF6D263C493619982FD3638E6135077311D08C961E1FE128F9107D29EBC6",
-            ["CsvColumnizer.dll"] = "9C9F3914A4ECD1E9A45A0B87845E942162DB8203BCEF05FCA8E8E4A6C10D6AC2",
-            ["CsvColumnizer.dll (x86)"] = "9C9F3914A4ECD1E9A45A0B87845E942162DB8203BCEF05FCA8E8E4A6C10D6AC2",
-            ["DefaultPlugins.dll"] = "8EA6195A67840581DA4987B3B2893C68D8DC6DCA919B180896258386B9DB2713",
-            ["FlashIconHighlighter.dll"] = "5095E95DD6AEED1747BB6CF259D550B2B3D530B6F925C47A7458ECEDBF2EBC60",
-            ["GlassfishColumnizer.dll"] = "66730D4646D90568BFDCE500363CF2215B52F538B1E9172A78ECC6CAE0DD1C27",
-            ["JsonColumnizer.dll"] = "7C064A5DE3A970C79518280D43E8C041322B4FBC27D0D8A77BC387DFD738936F",
-            ["JsonCompactColumnizer.dll"] = "5EEAFD0882DD1DBE5F0FFF92A65580737B775E43CA7F3A0DC4EFDE6A28B0DE5E",
-            ["Log4jXmlColumnizer.dll"] = "C8458E855FE59F799E2394500BF4991A7E5E7F8AA6B030E2B7A733322E2AFAEF",
-            ["LogExpert.Resources.dll"] = "F765E294A0EEEC525FA8992D22B1A666880CE2D0F720EFAF154D01EBB7A8AEED",
+            ["CsvColumnizer.dll"] = "024575D2CBD09E58AE7CFF058B92C3785006AD2280301B0DE0724409934F4BCA",
+            ["CsvColumnizer.dll (x86)"] = "024575D2CBD09E58AE7CFF058B92C3785006AD2280301B0DE0724409934F4BCA",
+            ["DefaultPlugins.dll"] = "19B0A154B48F99A616A8468E8AC45ACCF86B4402F9F4E7DC860C6FE1D7D92B13",
+            ["FlashIconHighlighter.dll"] = "4A488895316B01053DD3287604DC4344CCEA918EB09EB664009BC419F29FC021",
+            ["GlassfishColumnizer.dll"] = "93DF4EEDC1A695F06E7E09AB483782FA0FDC867BED61FB63BD25458389FA8E0E",
+            ["JsonColumnizer.dll"] = "C9538CA60C8E1ADFEAC74C75CAE7F1627311FF500804C6FD8B2EFEF068C6FFFE",
+            ["JsonCompactColumnizer.dll"] = "1F30ABDC119D4459A2272D96080F4BF0683D7420A624CC256C2F07EEE02B192A",
+            ["Log4jXmlColumnizer.dll"] = "D99A998A0E0C3969EB8B49CB6E8BD9CCC934641EEE18852B202244C837ADC7F5",
+            ["LogExpert.Resources.dll"] = "43FB2C2C6D53D1E2CDB0D8FD663AEE5CF3E4FC51A05D69DBFBBF2123E8F67935",
             ["Microsoft.Extensions.DependencyInjection.Abstractions.dll"] = "67FA4325000DB017DC0C35829B416F024F042D24EFB868BCF17A895EE6500A93",
             ["Microsoft.Extensions.DependencyInjection.Abstractions.dll (x86)"] = "67FA4325000DB017DC0C35829B416F024F042D24EFB868BCF17A895EE6500A93",
             ["Microsoft.Extensions.Logging.Abstractions.dll"] = "BB853130F5AFAF335BE7858D661F8212EC653835100F5A4E3AA2C66A4D4F685D",
             ["Microsoft.Extensions.Logging.Abstractions.dll (x86)"] = "BB853130F5AFAF335BE7858D661F8212EC653835100F5A4E3AA2C66A4D4F685D",
-            ["RegexColumnizer.dll"] = "009C8C7E56BB89C9448091A294894FE69C661DF35F9082CD2A092EEAF85E23A7",
-            ["SftpFileSystem.dll"] = "74624F9B6659F83B53B7FEC45267345B84BE3DB13C811E04926884E65C32D56E",
-            ["SftpFileSystem.dll (x86)"] = "03A1F8E1A3DF8915404A2653FE55B39B196EFD19C6DE42586D0B9822EFFBC617",
-            ["SftpFileSystem.Resources.dll"] = "09F468603D3EAF56B13058BCE104CF9EA3F7B757352E9199D54486C8734AC47B",
-            ["SftpFileSystem.Resources.dll (x86)"] = "09F468603D3EAF56B13058BCE104CF9EA3F7B757352E9199D54486C8734AC47B",
+            ["RegexColumnizer.dll"] = "926229B7C704E367BA768E44981D133E6B26356CCEC4BCF0108EC77B2521C33A",
+            ["SftpFileSystem.dll"] = "066BDA9245EDCECCD49E3C36B6ACC05E52C8C34D25A1A9406E403987E603FC57",
+            ["SftpFileSystem.dll (x86)"] = "A30EB5C2D2E8A403C0ADF179AB626278689198E64935DA8BA108B33FB164AECA",
+            ["SftpFileSystem.Resources.dll"] = "E68455B141D714A19779E717558DEEA6C9A9829ECF5A3C5EDCD65F18C06E6D33",
+            ["SftpFileSystem.Resources.dll (x86)"] = "E68455B141D714A19779E717558DEEA6C9A9829ECF5A3C5EDCD65F18C06E6D33",
 
         };
     }