run CI on release branch

Fix: Should not throw on ARJ detection

.github/workflows/dotnetcore.yml

@@ -3,6 +3,7 @@ on:
   push:
     branches:
       - 'master'
+      - 'release'
   pull_request:
     types: [ opened, synchronize, reopened, ready_for_review ]
 

src/SharpCompress/Archives/AbstractArchive.cs

@@ -172,9 +172,4 @@ public abstract class AbstractArchive<TEntry, TVolume> : IArchive, IArchiveExtra
             return Entries.All(x => x.IsComplete);
         }
     }
-
-    public virtual bool IsMultiVolume =>
-        _sourceStream?.Files.Count > 1 || _sourceStream?.Streams.Count > 1;
-
-    public virtual bool SupportsMultiThreading => false;
 }

src/SharpCompress/Archives/IArchive.cs

@@ -45,14 +45,4 @@ public interface IArchive : IDisposable
     /// The total size of the files as uncompressed in the archive.
     /// </summary>
     long TotalUncompressSize { get; }
-
-    /// <summary>
-    /// Is the archive part of a multi-volume set.
-    /// </summary>
-    bool IsMultiVolume { get; }
-
-    /// <summary>
-    /// Does the archive support multi-threaded extraction.
-    /// </summary>
-    bool SupportsMultiThreading { get; }
 }

src/SharpCompress/Archives/IArchiveEntryExtensions.cs

@@ -88,7 +88,7 @@ public static class IArchiveEntryExtensions
             entry,
             destinationDirectory,
             options,
-            entry.WriteToFileAsync,
+            (x, opt) => entry.WriteToFileAsync(x, opt, cancellationToken),
             cancellationToken
         );
 
@@ -124,10 +124,10 @@ public static class IArchiveEntryExtensions
             entry,
             destinationFileName,
             options,
-            async (x, fm, ct) =>
+            async (x, fm) =>
             {
                 using var fs = File.Open(destinationFileName, fm);
-                await entry.WriteToAsync(fs, ct).ConfigureAwait(false);
+                await entry.WriteToAsync(fs, cancellationToken).ConfigureAwait(false);
             },
             cancellationToken
         );

src/SharpCompress/Archives/Rar/FileInfoRarArchiveVolume.cs

@@ -0,0 +1,39 @@
+using System.Collections.Generic;
+using System.Collections.ObjectModel;
+using System.IO;
+using System.Linq;
+using SharpCompress.Common.Rar;
+using SharpCompress.Common.Rar.Headers;
+using SharpCompress.IO;
+using SharpCompress.Readers;
+
+namespace SharpCompress.Archives.Rar;
+
+/// <summary>
+/// A rar part based on a FileInfo object
+/// </summary>
+internal class FileInfoRarArchiveVolume : RarVolume
+{
+    internal FileInfoRarArchiveVolume(FileInfo fileInfo, ReaderOptions options, int index)
+        : base(StreamingMode.Seekable, fileInfo.OpenRead(), FixOptions(options), index)
+    {
+        FileInfo = fileInfo;
+        FileParts = GetVolumeFileParts().ToArray().ToReadOnly();
+    }
+
+    private static ReaderOptions FixOptions(ReaderOptions options)
+    {
+        //make sure we're closing streams with fileinfo
+        options.LeaveStreamOpen = false;
+        return options;
+    }
+
+    internal ReadOnlyCollection<RarFilePart> FileParts { get; }
+
+    internal FileInfo FileInfo { get; }
+
+    internal override RarFilePart CreateFilePart(MarkHeader markHeader, FileHeader fileHeader) =>
+        new FileInfoRarFilePart(this, ReaderOptions.Password, markHeader, fileHeader, FileInfo);
+
+    internal override IEnumerable<RarFilePart> ReadFileParts() => FileParts;
+}

src/SharpCompress/Archives/Rar/FileInfoRarFilePart.cs

@@ -0,0 +1,21 @@
+using System.IO;
+using SharpCompress.Common.Rar.Headers;
+
+namespace SharpCompress.Archives.Rar;
+
+internal sealed class FileInfoRarFilePart : SeekableFilePart
+{
+    internal FileInfoRarFilePart(
+        FileInfoRarArchiveVolume volume,
+        string? password,
+        MarkHeader mh,
+        FileHeader fh,
+        FileInfo fi
+    )
+        : base(mh, fh, volume.Index, volume.Stream, password) => FileInfo = fi;
+
+    internal FileInfo FileInfo { get; }
+
+    internal override string FilePartName =>
+        "Rar File: " + FileInfo.FullName + " File Entry: " + FileHeader.FileName;
+}

src/SharpCompress/Archives/Rar/RarArchive.cs

@@ -47,9 +47,9 @@ public class RarArchive : AbstractArchive<RarArchiveEntry, RarVolume>
     {
         sourceStream.LoadAllParts(); //request all streams
         var streams = sourceStream.Streams.ToArray();
+        var i = 0;
         if (streams.Length > 1 && IsRarFile(streams[1], ReaderOptions)) //test part 2 - true = multipart not split
         {
-            var i = 0;
             sourceStream.IsVolumes = true;
             streams[1].Position = 0;
             sourceStream.Position = 0;
@@ -57,18 +57,12 @@ public class RarArchive : AbstractArchive<RarArchiveEntry, RarVolume>
             return sourceStream.Streams.Select(a => new StreamRarArchiveVolume(
                 a,
                 ReaderOptions,
-                i++,
-                IsMultiVolume
+                i++
             ));
         }
 
         //split mode or single file
-        return new StreamRarArchiveVolume(
-            sourceStream,
-            ReaderOptions,
-            0,
-            IsMultiVolume
-        ).AsEnumerable();
+        return new StreamRarArchiveVolume(sourceStream, ReaderOptions, i++).AsEnumerable();
     }
 
     protected override IReader CreateReaderForSolidExtraction()
@@ -89,7 +83,6 @@ public class RarArchive : AbstractArchive<RarArchiveEntry, RarVolume>
     }
 
     public override bool IsSolid => Volumes.First().IsSolidArchive;
-    public override bool SupportsMultiThreading => !IsMultiVolume && !IsSolid;
 
     public virtual int MinVersion => Volumes.First().MinVersion;
     public virtual int MaxVersion => Volumes.First().MaxVersion;

src/SharpCompress/Archives/Rar/RarArchiveEntry.cs

@@ -134,6 +134,4 @@ public class RarArchiveEntry : RarEntry, IArchiveEntry
             );
         }
     }
-
-    public override bool SupportsMultiThreading => Parts.Single().SupportsMultiThreading;
 }

src/SharpCompress/Archives/Rar/SeekableFilePart.cs

@@ -1,29 +1,25 @@
 using System.IO;
 using SharpCompress.Common.Rar;
 using SharpCompress.Common.Rar.Headers;
-using SharpCompress.IO;
 
 namespace SharpCompress.Archives.Rar;
 
-internal class SeekableRarFilePart : RarFilePart
+internal class SeekableFilePart : RarFilePart
 {
     private readonly Stream _stream;
     private readonly string? _password;
-    private readonly bool _isMultiVolume;
 
-    internal SeekableRarFilePart(
+    internal SeekableFilePart(
         MarkHeader mh,
         FileHeader fh,
         int index,
         Stream stream,
-        string? password,
-        bool isMultiVolume
+        string? password
     )
         : base(mh, fh, index)
     {
         _stream = stream;
         _password = password;
-        _isMultiVolume = isMultiVolume;
     }
 
     internal override Stream GetCompressedStream()
@@ -46,7 +42,4 @@ internal class SeekableRarFilePart : RarFilePart
     }
 
     internal override string FilePartName => "Unknown Stream - File Entry: " + FileHeader.FileName;
-
-    public override bool SupportsMultiThreading =>
-        !_isMultiVolume && _stream is SourceStream ss && ss.IsFileMode && ss.Files.Count == 1;
 }

src/SharpCompress/Archives/Rar/StreamRarArchiveVolume.cs

@@ -9,28 +9,11 @@ namespace SharpCompress.Archives.Rar;
 
 internal class StreamRarArchiveVolume : RarVolume
 {
-    private readonly bool _isMultiVolume;
-
-    internal StreamRarArchiveVolume(
-        Stream stream,
-        ReaderOptions options,
-        int index,
-        bool isMultiVolume
-    )
-        : base(StreamingMode.Seekable, stream, options, index)
-    {
-        _isMultiVolume = isMultiVolume;
-    }
+    internal StreamRarArchiveVolume(Stream stream, ReaderOptions options, int index)
+        : base(StreamingMode.Seekable, stream, options, index) { }
 
     internal override IEnumerable<RarFilePart> ReadFileParts() => GetVolumeFileParts();
 
     internal override RarFilePart CreateFilePart(MarkHeader markHeader, FileHeader fileHeader) =>
-        new SeekableRarFilePart(
-            markHeader,
-            fileHeader,
-            Index,
-            Stream,
-            ReaderOptions.Password,
-            _isMultiVolume
-        );
+        new SeekableFilePart(markHeader, fileHeader, Index, Stream, ReaderOptions.Password);
 }

src/SharpCompress/Archives/Zip/ZipArchive.cs

@@ -283,12 +283,7 @@ public class ZipArchive : AbstractWritableArchive<ZipArchiveEntry, ZipVolume>
 
                             yield return new ZipArchiveEntry(
                                 this,
-                                new SeekableZipFilePart(
-                                    headerFactory.NotNull(),
-                                    deh,
-                                    s,
-                                    IsMultiVolume
-                                )
+                                new SeekableZipFilePart(headerFactory.NotNull(), deh, s)
                             );
                         }
                         break;
@@ -390,6 +385,4 @@ public class ZipArchive : AbstractWritableArchive<ZipArchiveEntry, ZipVolume>
         ((IStreamStack)stream).StackSeek(0);
         return ZipReader.Open(stream, ReaderOptions, Entries);
     }
-
-    public override bool SupportsMultiThreading => !IsMultiVolume;
 }

src/SharpCompress/Archives/Zip/ZipArchiveEntry.cs

@@ -23,7 +23,5 @@ public class ZipArchiveEntry : ZipEntry, IArchiveEntry
 
     public bool IsComplete => true;
 
-    public override bool SupportsMultiThreading => Parts.Single().SupportsMultiThreading;
-
     #endregion
 }

src/SharpCompress/Common/Entry.cs

@@ -87,5 +87,4 @@ public abstract class Entry : IEntry
     /// Entry file attribute.
     /// </summary>
     public virtual int? Attrib => throw new NotImplementedException();
-    public virtual bool SupportsMultiThreading => false;
 }

src/SharpCompress/Common/ExtractionMethods.cs

@@ -128,7 +128,7 @@ internal static class ExtractionMethods
         IEntry entry,
         string destinationDirectory,
         ExtractionOptions? options,
-        Func<string, ExtractionOptions?, CancellationToken, Task> writeAsync,
+        Func<string, ExtractionOptions?, Task> writeAsync,
         CancellationToken cancellationToken = default
     )
     {
@@ -189,7 +189,7 @@ internal static class ExtractionMethods
                     "Entry is trying to write a file outside of the destination directory."
                 );
             }
-            await writeAsync(destinationFileName, options, cancellationToken).ConfigureAwait(false);
+            await writeAsync(destinationFileName, options).ConfigureAwait(false);
         }
         else if (options.ExtractFullPath && !Directory.Exists(destinationFileName))
         {
@@ -201,7 +201,7 @@ internal static class ExtractionMethods
         IEntry entry,
         string destinationFileName,
         ExtractionOptions? options,
-        Func<string, FileMode, CancellationToken, Task> openAndWriteAsync,
+        Func<string, FileMode, Task> openAndWriteAsync,
         CancellationToken cancellationToken = default
     )
     {
@@ -225,8 +225,7 @@ internal static class ExtractionMethods
                 fm = FileMode.CreateNew;
             }
 
-            await openAndWriteAsync(destinationFileName, fm, cancellationToken)
-                .ConfigureAwait(false);
+            await openAndWriteAsync(destinationFileName, fm).ConfigureAwait(false);
             entry.PreserveExtractionOptions(destinationFileName, options);
         }
     }

src/SharpCompress/Common/FilePart.cs

@@ -14,6 +14,4 @@ public abstract class FilePart
     internal abstract Stream? GetCompressedStream();
     internal abstract Stream? GetRawStream();
     internal bool Skipped { get; set; }
-
-    public virtual bool SupportsMultiThreading => false;
 }

src/SharpCompress/Common/IEntry.cs

@@ -21,5 +21,4 @@ public interface IEntry
     DateTime? LastModifiedTime { get; }
     long Size { get; }
     int? Attrib { get; }
-    bool SupportsMultiThreading { get; }
 }

src/SharpCompress/Common/Zip/SeekableZipFilePart.cs

@@ -1,6 +1,5 @@
 using System.IO;
 using SharpCompress.Common.Zip.Headers;
-using SharpCompress.IO;
 
 namespace SharpCompress.Common.Zip;
 
@@ -8,19 +7,13 @@ internal class SeekableZipFilePart : ZipFilePart
 {
     private bool _isLocalHeaderLoaded;
     private readonly SeekableZipHeaderFactory _headerFactory;
-    private readonly bool _isMultiVolume;
 
     internal SeekableZipFilePart(
         SeekableZipHeaderFactory headerFactory,
         DirectoryEntryHeader header,
-        Stream stream,
-        bool isMultiVolume
+        Stream stream
     )
-        : base(header, stream)
-    {
-        _headerFactory = headerFactory;
-        _isMultiVolume = isMultiVolume;
-    }
+        : base(header, stream) => _headerFactory = headerFactory;
 
     internal override Stream GetCompressedStream()
     {
@@ -37,20 +30,8 @@ internal class SeekableZipFilePart : ZipFilePart
 
     protected override Stream CreateBaseStream()
     {
-        if (!_isMultiVolume && BaseStream is SourceStream ss)
-        {
-            if (ss.IsFileMode && ss.Files.Count == 1)
-            {
-                var fileStream = ss.CurrentFile.OpenRead();
-                fileStream.Position = Header.DataStartPosition.NotNull();
-                return fileStream;
-            }
-        }
         BaseStream.Position = Header.DataStartPosition.NotNull();
 
         return BaseStream;
     }
-
-    public override bool SupportsMultiThreading =>
-        !_isMultiVolume && BaseStream is SourceStream ss && ss.IsFileMode && ss.Files.Count == 1;
 }

src/SharpCompress/Compressors/BZip2/CBZip2OutputStream.cs

@@ -544,6 +544,12 @@ internal sealed class CBZip2OutputStream : Stream, IStreamStack
 
     private void EndBlock()
     {
+        // Skip block processing for empty input (no data written)
+        if (last < 0)
+        {
+            return;
+        }
+
         blockCRC = mCrc.GetFinalCRC();
         combinedCRC = (combinedCRC << 1) | (int)(((uint)combinedCRC) >> 31);
         combinedCRC ^= blockCRC;

src/SharpCompress/Compressors/Rar/MultiVolumeReadOnlyStream.cs

@@ -62,6 +62,10 @@ internal sealed class MultiVolumeReadOnlyStream : Stream, IStreamStack
         base.Dispose(disposing);
         if (disposing)
         {
+#if DEBUG_STREAMS
+            this.DebugDispose(typeof(MultiVolumeReadOnlyStream));
+#endif
+
             if (filePartEnumerator != null)
             {
                 filePartEnumerator.Dispose();

src/SharpCompress/Compressors/Rar/RarStream.cs

@@ -82,6 +82,9 @@ internal class RarStream : Stream, IStreamStack
         {
             if (disposing)
             {
+#if DEBUG_STREAMS
+                this.DebugDispose(typeof(RarStream));
+#endif
                 ArrayPool<byte>.Shared.Return(this.tmpBuffer);
                 this.tmpBuffer = null;
             }

src/SharpCompress/Factories/ArjFactory.cs

@@ -28,12 +28,19 @@ namespace SharpCompress.Factories
             int bufferSize = ReaderOptions.DefaultBufferSize
         )
         {
-            var arjHeader = new ArjMainHeader(new ArchiveEncoding());
-            if (arjHeader.Read(stream) == null)
+            try
+            {
+                var arjHeader = new ArjMainHeader(new ArchiveEncoding());
+                if (arjHeader.Read(stream) == null)
+                {
+                    return false;
+                }
+                return true;
+            }
+            catch
             {
                 return false;
             }
-            return true;
         }
 
         public IReader OpenReader(Stream stream, ReaderOptions? options) =>

src/SharpCompress/IO/SourceStream.cs

@@ -15,7 +15,7 @@ public class SourceStream : Stream, IStreamStack
 #endif
     int IStreamStack.DefaultBufferSize { get; set; }
 
-    Stream IStreamStack.BaseStream() => _streams[_streamIndex];
+    Stream IStreamStack.BaseStream() => _streams[_stream];
 
     int IStreamStack.BufferSize
     {
@@ -35,7 +35,7 @@ public class SourceStream : Stream, IStreamStack
     private readonly List<Stream> _streams;
     private readonly Func<int, FileInfo?>? _getFilePart;
     private readonly Func<int, Stream?>? _getStreamPart;
-    private int _streamIndex;
+    private int _stream;
 
     public SourceStream(FileInfo file, Func<int, FileInfo?> getPart, ReaderOptions options)
         : this(null, null, file, getPart, options) { }
@@ -59,7 +59,7 @@ public class SourceStream : Stream, IStreamStack
 
         if (!IsFileMode)
         {
-            _streams.Add(stream.NotNull("stream is null"));
+            _streams.Add(stream!);
             _getStreamPart = getStreamPart;
             _getFilePart = _ => null;
             if (stream is FileStream fileStream)
@@ -69,12 +69,12 @@ public class SourceStream : Stream, IStreamStack
         }
         else
         {
-            _files.Add(file.NotNull("file is null"));
+            _files.Add(file!);
             _streams.Add(_files[0].OpenRead());
             _getFilePart = getFilePart;
             _getStreamPart = _ => null;
         }
-        _streamIndex = 0;
+        _stream = 0;
         _prevSize = 0;
 
 #if DEBUG_STREAMS
@@ -93,12 +93,10 @@ public class SourceStream : Stream, IStreamStack
     public ReaderOptions ReaderOptions { get; }
     public bool IsFileMode { get; }
 
-    public IReadOnlyList<FileInfo> Files => _files;
-    public IReadOnlyList<Stream> Streams => _streams;
+    public IEnumerable<FileInfo> Files => _files;
+    public IEnumerable<Stream> Streams => _streams;
 
-    private Stream Current => _streams[_streamIndex];
-
-    public FileInfo CurrentFile => _files[_streamIndex];
+    private Stream Current => _streams[_stream];
 
     public bool LoadStream(int index) //ensure all parts to id are loaded
     {
@@ -109,7 +107,7 @@ public class SourceStream : Stream, IStreamStack
                 var f = _getFilePart.NotNull("GetFilePart is null")(_streams.Count);
                 if (f == null)
                 {
-                    _streamIndex = _streams.Count - 1;
+                    _stream = _streams.Count - 1;
                     return false;
                 }
                 //throw new Exception($"File part {idx} not available.");
@@ -121,7 +119,7 @@ public class SourceStream : Stream, IStreamStack
                 var s = _getStreamPart.NotNull("GetStreamPart is null")(_streams.Count);
                 if (s == null)
                 {
-                    _streamIndex = _streams.Count - 1;
+                    _stream = _streams.Count - 1;
                     return false;
                 }
                 //throw new Exception($"Stream part {idx} not available.");
@@ -139,10 +137,10 @@ public class SourceStream : Stream, IStreamStack
     {
         if (LoadStream(idx))
         {
-            _streamIndex = idx;
+            _stream = idx;
         }
 
-        return _streamIndex == idx;
+        return _stream == idx;
     }
 
     public override bool CanRead => true;
@@ -186,7 +184,7 @@ public class SourceStream : Stream, IStreamStack
                 var length = Current.Length;
 
                 // Load next file if present
-                if (!SetStream(_streamIndex + 1))
+                if (!SetStream(_stream + 1))
                 {
                     break;
                 }
@@ -225,7 +223,7 @@ public class SourceStream : Stream, IStreamStack
             while (_prevSize + Current.Length < pos)
             {
                 _prevSize += Current.Length;
-                SetStream(_streamIndex + 1);
+                SetStream(_stream + 1);
             }
         }
 
@@ -275,7 +273,7 @@ public class SourceStream : Stream, IStreamStack
                 var length = Current.Length;
 
                 // Load next file if present
-                if (!SetStream(_streamIndex + 1))
+                if (!SetStream(_stream + 1))
                 {
                     break;
                 }
@@ -324,7 +322,7 @@ public class SourceStream : Stream, IStreamStack
                 var length = Current.Length;
 
                 // Load next file if present
-                if (!SetStream(_streamIndex + 1))
+                if (!SetStream(_stream + 1))
                 {
                     break;
                 }

src/SharpCompress/Readers/IReaderExtensions.cs

@@ -82,7 +82,7 @@ public static class IReaderExtensions
                 reader.Entry,
                 destinationDirectory,
                 options,
-                reader.WriteEntryToFileAsync,
+                (fileName, opts) => reader.WriteEntryToFileAsync(fileName, opts, cancellationToken),
                 cancellationToken
             )
             .ConfigureAwait(false);
@@ -101,10 +101,10 @@ public static class IReaderExtensions
                 reader.Entry,
                 destinationFileName,
                 options,
-                async (x, fm, ct) =>
+                async (x, fm) =>
                 {
                     using var fs = File.Open(destinationFileName, fm);
-                    await reader.WriteEntryToAsync(fs, ct).ConfigureAwait(false);
+                    await reader.WriteEntryToAsync(fs, cancellationToken).ConfigureAwait(false);
                 },
                 cancellationToken
             )

src/SharpCompress/SharpCompress.csproj

@@ -2,9 +2,9 @@
   <PropertyGroup>
     <AssemblyTitle>SharpCompress - Pure C# Decompression/Compression</AssemblyTitle>
     <NeutralLanguage>en-US</NeutralLanguage>
-    <VersionPrefix>0.41.0</VersionPrefix>
-    <AssemblyVersion>0.41.0</AssemblyVersion>
-    <FileVersion>0.41.0</FileVersion>
+    <VersionPrefix>0.42.1</VersionPrefix>
+    <AssemblyVersion>0.42.1</AssemblyVersion>
+    <FileVersion>0.42.1</FileVersion>
     <Authors>Adam Hathcock</Authors>
     <TargetFrameworks>net48;net481;netstandard2.0;net6.0;net8.0</TargetFrameworks>
     <AssemblyName>SharpCompress</AssemblyName>

tests/SharpCompress.Test/ArchiveTests.cs

@@ -134,7 +134,6 @@ public class ArchiveTests : ReaderTests
                 {
                     foreach (var entry in archive.Entries.Where(entry => !entry.IsDirectory))
                     {
-                        Assert.False(entry.SupportsMultiThreading);
                         entry.WriteToDirectory(
                             SCRATCH_FILES_PATH,
                             new ExtractionOptions { ExtractFullPath = true, Overwrite = true }
@@ -267,31 +266,6 @@ public class ArchiveTests : ReaderTests
         VerifyFiles();
     }
 
-    protected async Task ArchiveFileRead_Multithreaded(
-        IArchiveFactory archiveFactory,
-        string testArchive,
-        ReaderOptions? readerOptions = null
-    )
-    {
-        testArchive = Path.Combine(TEST_ARCHIVES_PATH, testArchive);
-        var tasks = new List<Task>();
-        using (var archive = archiveFactory.Open(new FileInfo(testArchive), readerOptions))
-        {
-            Assert.True(archive.SupportsMultiThreading);
-            foreach (var entry in archive.Entries.Where(entry => !entry.IsDirectory))
-            {
-                Assert.True(entry.SupportsMultiThreading);
-                var t = entry.WriteToDirectoryAsync(
-                    SCRATCH_FILES_PATH,
-                    new ExtractionOptions { ExtractFullPath = true, Overwrite = true }
-                );
-                tasks.Add(t);
-            }
-        }
-        await Task.WhenAll(tasks);
-        VerifyFiles();
-    }
-
     protected void ArchiveFileRead(
         IArchiveFactory archiveFactory,
         string testArchive,
@@ -315,11 +289,6 @@ public class ArchiveTests : ReaderTests
     protected void ArchiveFileRead(string testArchive, ReaderOptions? readerOptions = null) =>
         ArchiveFileRead(ArchiveFactory.AutoFactory, testArchive, readerOptions);
 
-    protected Task ArchiveFileRead_Multithreaded(
-        string testArchive,
-        ReaderOptions? readerOptions = null
-    ) => ArchiveFileRead_Multithreaded(ArchiveFactory.AutoFactory, testArchive, readerOptions);
-
     protected void ArchiveFileSkip(
         string testArchive,
         string fileOrder,
@@ -685,4 +654,31 @@ public class ArchiveTests : ReaderTests
             Assert.Equal(3, archive.Entries.Count());
         }
     }
+
+    [Fact]
+    public void ArchiveFactory_IsArchive_NonArchiveFile_ShouldReturnFalse()
+    {
+        // Test that ArchiveFactory.IsArchive returns false instead of throwing
+        // when called on a non-archive file (regression test for issue #1064)
+        using (var stream = new MemoryStream(new byte[] { 0x00, 0x01, 0x02, 0x03, 0x04 }))
+        {
+            var result = ArchiveFactory.IsArchive(stream, out var type);
+            Assert.False(result);
+            Assert.Null(type);
+        }
+    }
+
+    [Fact]
+    public void ArchiveFactory_IsArchive_ValidArchive_ShouldReturnTrue()
+    {
+        // Test that ArchiveFactory.IsArchive correctly identifies valid archives
+        var testArchive = Path.Combine(TEST_ARCHIVES_PATH, "Zip.bzip2.noEmptyDirs.zip");
+
+        using (var stream = File.OpenRead(testArchive))
+        {
+            var result = ArchiveFactory.IsArchive(stream, out var type);
+            Assert.True(result);
+            Assert.Equal(ArchiveType.Zip, type);
+        }
+    }
 }

tests/SharpCompress.Test/Rar/RarArchiveTests.cs

@@ -1,6 +1,5 @@
 using System.IO;
 using System.Linq;
-using System.Threading.Tasks;
 using SharpCompress.Archives;
 using SharpCompress.Archives.Rar;
 using SharpCompress.Common;
@@ -293,15 +292,9 @@ public class RarArchiveTests : ArchiveTests
     [Fact]
     public void Rar_ArchiveFileRead() => ArchiveFileRead("Rar.rar");
 
-    [Fact]
-    public Task Rar_ArchiveFileRead_Multithreaded() => ArchiveFileRead_Multithreaded("Rar.rar");
-
     [Fact]
     public void Rar5_ArchiveFileRead() => ArchiveFileRead("Rar5.rar");
 
-    [Fact]
-    public Task Rar5_ArchiveFileRead_Multithreaded() => ArchiveFileRead_Multithreaded("Rar5.rar");
-
     [Fact]
     public void Rar_ArchiveFileRead_HasDirectories() =>
         DoRar_ArchiveFileRead_HasDirectories("Rar.rar");
@@ -366,9 +359,6 @@ public class RarArchiveTests : ArchiveTests
     [Fact]
     public void Rar2_ArchiveFileRead() => ArchiveFileRead("Rar2.rar");
 
-    [Fact]
-    public Task Rar2_ArchiveFileRead_Multithreaded() => ArchiveFileRead_Multithreaded("Rar2.rar");
-
     [Fact]
     public void Rar15_ArchiveFileRead()
     {

tests/SharpCompress.Test/Zip/ZipArchiveTests.cs

@@ -2,7 +2,6 @@ using System;
 using System.IO;
 using System.Linq;
 using System.Text;
-using System.Threading.Tasks;
 using SharpCompress.Archives;
 using SharpCompress.Archives.Zip;
 using SharpCompress.Common;
@@ -89,10 +88,6 @@ public class ZipArchiveTests : ArchiveTests
     [Fact]
     public void Zip_Deflate_ArchiveFileRead() => ArchiveFileRead("Zip.deflate.zip");
 
-    [Fact]
-    public Task Zip_Deflate_ArchiveFileRead_Multithreaded() =>
-        ArchiveFileRead_Multithreaded("Zip.deflate.zip");
-
     [Fact]
     public void Zip_Deflate_ArchiveExtractToDirectory() =>
         ArchiveExtractToDirectory("Zip.deflate.zip");

tests/SharpCompress.Test/Zip/ZipWriterTests.cs

@@ -1,5 +1,7 @@
+using System.IO;
 using System.Text;
 using SharpCompress.Common;
+using SharpCompress.Writers;
 using Xunit;
 
 namespace SharpCompress.Test.Zip;
@@ -9,6 +11,42 @@ public class ZipWriterTests : WriterTests
     public ZipWriterTests()
         : base(ArchiveType.Zip) { }
 
+    [Fact]
+    public void Zip_BZip2_Write_EmptyFile()
+    {
+        // Test that writing an empty file with BZip2 compression doesn't throw DivideByZeroException
+        using var memoryStream = new MemoryStream();
+        var options = new WriterOptions(CompressionType.BZip2)
+        {
+            ArchiveEncoding = new ArchiveEncoding { Default = new UTF8Encoding(false) },
+        };
+
+        using (var writer = WriterFactory.Open(memoryStream, ArchiveType.Zip, options))
+        {
+            writer.Write("test-folder/zero-byte-file.txt", Stream.Null);
+        }
+
+        Assert.True(memoryStream.Length > 0);
+    }
+
+    [Fact]
+    public void Zip_BZip2_Write_EmptyFolder()
+    {
+        // Test that writing an empty folder entry with BZip2 compression doesn't throw DivideByZeroException
+        using var memoryStream = new MemoryStream();
+        var options = new WriterOptions(CompressionType.BZip2)
+        {
+            ArchiveEncoding = new ArchiveEncoding { Default = new UTF8Encoding(false) },
+        };
+
+        using (var writer = WriterFactory.Open(memoryStream, ArchiveType.Zip, options))
+        {
+            writer.Write("test-empty-folder/", Stream.Null);
+        }
+
+        Assert.True(memoryStream.Length > 0);
+    }
+
     [Fact]
     public void Zip_Deflate_Write() =>
         Write(