Merge pull request #914 from adamhathcock/update-deps

Update dependencies and csharpier

.config/dotnet-tools.json

@@ -3,10 +3,11 @@
   "isRoot": true,
   "tools": {
     "csharpier": {
-      "version": "0.27.3",
+      "version": "1.0.2",
       "commands": [
-        "dotnet-csharpier"
-      ]
+        "csharpier"
+      ],
+      "rollForward": false
     }
   }
 }

.editorconfig

@@ -70,7 +70,7 @@ indent_style = tab
 
 [*.{cs,csx,cake,vb,vbx}]
 # Default Severity for all .NET Code Style rules below
-dotnet_analyzer_diagnostic.severity = warning
+dotnet_analyzer_diagnostic.severity = silent
 
 ##########################################
 # File Header (Uncomment to support file headers)
@@ -269,6 +269,8 @@ dotnet_diagnostic.CA1305.severity = suggestion
 dotnet_diagnostic.CA1307.severity = suggestion
 dotnet_diagnostic.CA1309.severity = suggestion
 dotnet_diagnostic.CA1310.severity = error
+dotnet_diagnostic.CA1507.severity = suggestion
+dotnet_diagnostic.CA1513.severity = suggestion
 dotnet_diagnostic.CA1707.severity = suggestion
 dotnet_diagnostic.CA1708.severity = suggestion
 dotnet_diagnostic.CA1711.severity = suggestion
@@ -286,6 +288,7 @@ dotnet_diagnostic.CA1834.severity = error
 dotnet_diagnostic.CA1845.severity = suggestion
 dotnet_diagnostic.CA1848.severity = suggestion
 dotnet_diagnostic.CA1852.severity = suggestion
+dotnet_diagnostic.CA1860.severity = silent
 dotnet_diagnostic.CA2016.severity = suggestion
 dotnet_diagnostic.CA2201.severity = error
 dotnet_diagnostic.CA2206.severity = error
@@ -303,13 +306,12 @@ dotnet_diagnostic.CS1998.severity = error
 dotnet_diagnostic.CS8602.severity = error
 dotnet_diagnostic.CS8604.severity = error
 dotnet_diagnostic.CS8618.severity = error
-dotnet_diagnostic.CS0618.severity = error
+dotnet_diagnostic.CS0618.severity = suggestion
 dotnet_diagnostic.CS1998.severity = error
 dotnet_diagnostic.CS4014.severity = error
 dotnet_diagnostic.CS8600.severity = error
 dotnet_diagnostic.CS8603.severity = error
 dotnet_diagnostic.CS8625.severity = error
-dotnet_diagnostic.CS8981.severity = suggestion
 
 dotnet_diagnostic.BL0005.severity = suggestion
 
@@ -318,7 +320,7 @@ dotnet_diagnostic.MVC1000.severity = suggestion
 dotnet_diagnostic.RZ10012.severity = error
 
 dotnet_diagnostic.IDE0004.severity = error # redundant cast
-dotnet_diagnostic.IDE0005.severity = error
+dotnet_diagnostic.IDE0005.severity = suggestion
 dotnet_diagnostic.IDE0007.severity = error # Use var
 dotnet_diagnostic.IDE0011.severity = error # Use braces on if statements
 dotnet_diagnostic.IDE0010.severity = silent # populate switch
@@ -329,7 +331,7 @@ dotnet_diagnostic.IDE0023.severity = suggestion # use expression body for operat
 dotnet_diagnostic.IDE0024.severity = silent # expression body for operators
 dotnet_diagnostic.IDE0025.severity = suggestion # use expression body for properties
 dotnet_diagnostic.IDE0027.severity = suggestion # Use expression body for accessors
-dotnet_diagnostic.IDE0028.severity = silent
+dotnet_diagnostic.IDE0028.severity = silent # expression body for accessors
 dotnet_diagnostic.IDE0032.severity = suggestion # Use auto property
 dotnet_diagnostic.IDE0033.severity = error # prefer tuple name
 dotnet_diagnostic.IDE0037.severity = suggestion # simplify anonymous type
@@ -337,7 +339,7 @@ dotnet_diagnostic.IDE0040.severity = error # modifiers required
 dotnet_diagnostic.IDE0041.severity = error # simplify null
 dotnet_diagnostic.IDE0042.severity = error # deconstruct variable
 dotnet_diagnostic.IDE0044.severity = suggestion # make field only when possible
-dotnet_diagnostic.IDE0047.severity = suggestion # paratemeter name
+dotnet_diagnostic.IDE0047.severity = suggestion # parameter name
 dotnet_diagnostic.IDE0051.severity = error # unused field
 dotnet_diagnostic.IDE0052.severity = error # unused member
 dotnet_diagnostic.IDE0053.severity = suggestion # lambda not needed
@@ -351,11 +353,20 @@ dotnet_diagnostic.IDE0066.severity = suggestion # switch expression
 dotnet_diagnostic.IDE0072.severity = suggestion # Populate switch - forces population of all cases even when default specified
 dotnet_diagnostic.IDE0078.severity = suggestion # use pattern matching
 dotnet_diagnostic.IDE0090.severity = suggestion # new can be simplified
-dotnet_diagnostic.IDE0130.severity = error # namespace folder structure
+dotnet_diagnostic.IDE0130.severity = suggestion # namespace folder structure
 dotnet_diagnostic.IDE0160.severity = silent # Use block namespaces ARE NOT required
 dotnet_diagnostic.IDE0161.severity = error # Please use file namespaces
 dotnet_diagnostic.IDE0200.severity = suggestion # lambda not needed
 dotnet_diagnostic.IDE1006.severity = suggestion # Naming rule violation: These words cannot contain lower case characters
+dotnet_diagnostic.IDE0260.severity = suggestion # Use pattern matching
+dotnet_diagnostic.IDE0270.severity = suggestion # Null check simplifcation
+dotnet_diagnostic.IDE0290.severity = error # Primary Constructor
+dotnet_diagnostic.IDE0300.severity = suggestion # Collection
+dotnet_diagnostic.IDE0305.severity = suggestion # Collection ToList
+
+dotnet_diagnostic.NX0001.severity = error
+dotnet_diagnostic.NX0002.severity = silent
+dotnet_diagnostic.NX0003.severity = silent
 
 ##########################################
 # Styles

Directory.Build.props

@@ -10,5 +10,7 @@
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
     <RunAnalyzersDuringLiveAnalysis>False</RunAnalyzersDuringLiveAnalysis>
     <RunAnalyzersDuringBuild>False</RunAnalyzersDuringBuild>
+    <ManagePackageVersionsCentrally>true</ManagePackageVersionsCentrally>
+    <RestorePackagesWithLockFile>true</RestorePackagesWithLockFile>
   </PropertyGroup>
 </Project>

Directory.Packages.props

@@ -0,0 +1,19 @@
+<Project>
+  <ItemGroup>
+    <PackageVersion Include="Bullseye" Version="6.0.0" />
+    <PackageVersion Include="AwesomeAssertions" Version="9.0.0" />
+    <PackageVersion Include="Glob" Version="1.1.9" />
+    <PackageVersion Include="Microsoft.Bcl.AsyncInterfaces" Version="8.0.0" />
+    <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="17.13.0" />
+    <PackageVersion Include="Mono.Posix.NETStandard" Version="1.0.0" />
+    <PackageVersion Include="SimpleExec" Version="12.0.0" />
+    <PackageVersion Include="System.Buffers" Version="4.6.0" />
+    <PackageVersion Include="System.Memory" Version="4.6.0" />
+    <PackageVersion Include="System.Text.Encoding.CodePages" Version="8.0.0" />
+    <PackageVersion Include="xunit" Version="2.9.3" />
+    <PackageVersion Include="xunit.runner.visualstudio" Version="3.1.0" />
+    <PackageVersion Include="xunit.SkippableFact" Version="1.5.23" />
+    <PackageVersion Include="ZstdSharp.Port" Version="0.8.5" />
+    <GlobalPackageReference Include="Microsoft.SourceLink.GitHub" Version="8.0.0" />
+  </ItemGroup>
+</Project>

FORMATS.md

@@ -11,7 +11,7 @@
 | Archive Format         | Compression Format(s)                             | Compress/Decompress | Archive API     | Reader API | Writer API    |
 | ---------------------- | ------------------------------------------------- | ------------------- | --------------- | ---------- | ------------- |
 | Rar                    | Rar                                               | Decompress (1)      | RarArchive      | RarReader  | N/A           |
-| Zip (2)                | None, DEFLATE, Deflate64, BZip2, LZMA/LZMA2, PPMd | Both                | ZipArchive      | ZipReader  | ZipWriter     |
+| Zip (2)                | None, Shrink, Reduce, Implode, DEFLATE, Deflate64, BZip2, LZMA/LZMA2, PPMd                           | Both                | ZipArchive      | ZipReader  | ZipWriter     | 
 | Tar                    | None                                              | Both                | TarArchive      | TarReader  | TarWriter (3) |
 | Tar.GZip               | DEFLATE                                           | Both                | TarArchive      | TarReader  | TarWriter (3) |
 | Tar.BZip2              | BZip2                                             | Both                | TarArchive      | TarReader  | TarWriter (3) |

NuGet.config

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="utf-8"?>
+<configuration>
+  <packageSourceMapping>
+    <!-- key value for <packageSource> should match key values from <packageSources> element -->
+    <packageSource key="nuget.org">
+      <package pattern="*" />
+    </packageSource>
+  </packageSourceMapping>
+</configuration>

README.md

@@ -1,12 +1,12 @@
 # SharpCompress
 
-SharpCompress is a compression library in pure C# for .NET Standard 2.0, 2.1, .NET Core 3.1 and .NET 5.0 that can unrar, un7zip, unzip, untar unbzip2, ungzip, unlzip with forward-only reading and file random access APIs. Write support for zip/tar/bzip2/gzip/lzip are implemented.
+SharpCompress is a compression library in pure C# for .NET Framework 4.62, .NET Standard 2.1, .NET 6.0 and NET 8.0 that can unrar, un7zip, unzip, untar unbzip2, ungzip, unlzip with forward-only reading and file random access APIs. Write support for zip/tar/bzip2/gzip/lzip are implemented.
 
 The major feature is support for non-seekable streams so large files can be processed on the fly (i.e. download stream).
 
 GitHub Actions Build -
 [![SharpCompress](https://github.com/adamhathcock/sharpcompress/actions/workflows/dotnetcore.yml/badge.svg)](https://github.com/adamhathcock/sharpcompress/actions/workflows/dotnetcore.yml)
-[![Static Badge](https://img.shields.io/badge/API%20Documentation-RobiniaDocs-43bc00?logo=readme&logoColor=white)](https://www.robiniadocs.com/d/sharpcompress/api/SharpCompress.html)
+[![Static Badge](https://img.shields.io/badge/API%20Docs-DNDocs-190088?logo=readme&logoColor=white)](https://dndocs.com/d/sharpcompress/api/index.html)
 
 ## Need Help?
 

SharpCompress.sln

@@ -17,6 +17,10 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Config", "Config", "{CDB425
 	ProjectSection(SolutionItems) = preProject
 		Directory.Build.props = Directory.Build.props
 		global.json = global.json
+		.editorconfig = .editorconfig
+		Directory.Packages.props = Directory.Packages.props
+		NuGet.config = NuGet.config
+		.github\workflows\dotnetcore.yml = .github\workflows\dotnetcore.yml
 	EndProjectSection
 EndProject
 Global

SharpCompress.sln.DotSettings

@@ -79,6 +79,10 @@
 	<s:String x:Key="/Default/CodeStyle/Naming/CSharpNaming/PredefinedNamingRules/=PrivateStaticFields/@EntryIndexedValue">&lt;Policy Inspect="True" Prefix="" Suffix="" Style="AA_BB" /&gt;</s:String>
 	<s:String x:Key="/Default/CodeStyle/Naming/CSharpNaming/PredefinedNamingRules/=PrivateStaticReadonly/@EntryIndexedValue">&lt;Policy Inspect="True" Prefix="" Suffix="" Style="AA_BB" /&gt;</s:String>
 	<s:String x:Key="/Default/CodeStyle/Naming/CSharpNaming/PredefinedNamingRules/=StaticReadonly/@EntryIndexedValue">&lt;Policy Inspect="True" Prefix="" Suffix="" Style="AA_BB" /&gt;</s:String>
+	<s:String x:Key="/Default/CodeStyle/Naming/CSharpNaming/UserRules/=15b5b1f1_002D457c_002D4ca6_002Db278_002D5615aedc07d3/@EntryIndexedValue">&lt;Policy&gt;&lt;Descriptor Staticness="Static" AccessRightKinds="Private" Description="Static readonly fields (private)"&gt;&lt;ElementKinds&gt;&lt;Kind Name="READONLY_FIELD" /&gt;&lt;/ElementKinds&gt;&lt;/Descriptor&gt;&lt;Policy Inspect="True" Prefix="" Suffix="" Style="AA_BB" /&gt;&lt;/Policy&gt;</s:String>
+	<s:String x:Key="/Default/CodeStyle/Naming/CSharpNaming/UserRules/=4a98fdf6_002D7d98_002D4f5a_002Dafeb_002Dea44ad98c70c/@EntryIndexedValue">&lt;Policy&gt;&lt;Descriptor Staticness="Instance" AccessRightKinds="Private" Description="Instance fields (private)"&gt;&lt;ElementKinds&gt;&lt;Kind Name="FIELD" /&gt;&lt;Kind Name="READONLY_FIELD" /&gt;&lt;/ElementKinds&gt;&lt;/Descriptor&gt;&lt;Policy Inspect="True" Prefix="_" Suffix="" Style="aaBb" /&gt;&lt;/Policy&gt;</s:String>
+	<s:String x:Key="/Default/CodeStyle/Naming/CSharpNaming/UserRules/=c873eafb_002Dd57f_002D481d_002D8c93_002D77f6863c2f88/@EntryIndexedValue">&lt;Policy&gt;&lt;Descriptor Staticness="Static" AccessRightKinds="Protected, ProtectedInternal, Internal, Public, PrivateProtected" Description="Static readonly fields (not private)"&gt;&lt;ElementKinds&gt;&lt;Kind Name="READONLY_FIELD" /&gt;&lt;/ElementKinds&gt;&lt;/Descriptor&gt;&lt;Policy Inspect="True" Prefix="" Suffix="" Style="AA_BB" /&gt;&lt;/Policy&gt;</s:String>
+	<s:String x:Key="/Default/CodeStyle/Naming/CSharpNaming/UserRules/=f9fce829_002De6f4_002D4cb2_002D80f1_002D5497c44f51df/@EntryIndexedValue">&lt;Policy&gt;&lt;Descriptor Staticness="Static" AccessRightKinds="Private" Description="Static fields (private)"&gt;&lt;ElementKinds&gt;&lt;Kind Name="FIELD" /&gt;&lt;/ElementKinds&gt;&lt;/Descriptor&gt;&lt;Policy Inspect="True" Prefix="" Suffix="" Style="AA_BB" /&gt;&lt;/Policy&gt;</s:String>
 	<s:String x:Key="/Default/CodeStyle/Naming/JavaScriptNaming/UserRules/=JS_005FBLOCK_005FSCOPE_005FCONSTANT/@EntryIndexedValue">&lt;Policy Inspect="True" Prefix="" Suffix="" Style="aaBb" /&gt;</s:String>
 	<s:String x:Key="/Default/CodeStyle/Naming/JavaScriptNaming/UserRules/=JS_005FBLOCK_005FSCOPE_005FFUNCTION/@EntryIndexedValue">&lt;Policy Inspect="True" Prefix="" Suffix="" Style="aaBb" /&gt;</s:String>
 	<s:String x:Key="/Default/CodeStyle/Naming/JavaScriptNaming/UserRules/=JS_005FBLOCK_005FSCOPE_005FVARIABLE/@EntryIndexedValue">&lt;Policy Inspect="True" Prefix="" Suffix="" Style="aaBb" /&gt;</s:String>
@@ -127,6 +131,7 @@
 	<s:Boolean x:Key="/Default/Environment/SettingsMigration/IsMigratorApplied/=JetBrains_002EReSharper_002EPsi_002ECSharp_002ECodeStyle_002ESettingsUpgrade_002ECSharpPlaceAttributeOnSameLineMigration/@EntryIndexedValue">True</s:Boolean>
 	<s:Boolean x:Key="/Default/Environment/SettingsMigration/IsMigratorApplied/=JetBrains_002EReSharper_002EPsi_002ECSharp_002ECodeStyle_002ESettingsUpgrade_002EMigrateBlankLinesAroundFieldToBlankLinesAroundProperty/@EntryIndexedValue">True</s:Boolean>
 	<s:Boolean x:Key="/Default/Environment/SettingsMigration/IsMigratorApplied/=JetBrains_002EReSharper_002EPsi_002ECSharp_002ECodeStyle_002ESettingsUpgrade_002EMigrateThisQualifierSettings/@EntryIndexedValue">True</s:Boolean>
+	<s:Boolean x:Key="/Default/Environment/SettingsMigration/IsMigratorApplied/=JetBrains_002EReSharper_002EPsi_002ECSharp_002ECodeStyle_002ESettingsUpgrade_002EPredefinedNamingRulesToUserRulesUpgrade/@EntryIndexedValue">True</s:Boolean>
 	<s:String x:Key="/Default/Environment/UnitTesting/UnitTestSessionStore/Sessions/=6af8f80e_002D9fdd_002D4223_002D8e02_002D473db916f9b2/@EntryIndexedValue">&lt;SessionState ContinuousTestingIsOn="False" ContinuousTestingMode="0" FrameworkVersion="{x:Null}" IsLocked="False" Name="All tests from Solution" PlatformMonoPreference="{x:Null}" PlatformType="{x:Null}" xmlns="urn:schemas-jetbrains-com:jetbrains-ut-session" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"&gt;
   &lt;Solution /&gt;
 &lt;/SessionState&gt;</s:String></wpf:ResourceDictionary>

USAGE.md

@@ -27,7 +27,7 @@ To deal with the "correct" rules as well as the expectations of users, I've deci
 
 To be explicit though, consider always using the overloads that use `ReaderOptions` or `WriterOptions` and explicitly set `LeaveStreamOpen` the way you want.
 
-If using Compression Stream classes directly and you don't want the wrapped stream to be closed.  Use the `NonDisposingStream` as a wrapped to prevent the stream being disposed.  The change in 0.21 simplified a lot even though the usage is a bit more convoluted.
+If using Compression Stream classes directly and you don't want the wrapped stream to be closed.  Use the `NonDisposingStream` as a wrapper to prevent the stream being disposed.  The change in 0.21 simplified a lot even though the usage is a bit more convoluted.
 
 ## Samples
 
@@ -71,18 +71,34 @@ using (var archive = ZipArchive.Create())
 memoryStream.Position = 0;
 ```
 
-### Extract all files from a Rar file to a directory using RarArchive
+### Extract all files from a rar file to a directory using RarArchive
+
+Note: Extracting a solid rar or 7z file needs to be done in sequential order to get acceptable decompression speed.
+It is explicitly recommended to use `ExtractAllEntries` when extracting an entire `IArchive` instead of iterating over all its `Entries`.
+Alternatively, use `IArchive.WriteToDirectory`.
+
+```C#
+using (var archive = RarArchive.Open("Test.rar"))
+{
+    using (var reader = archive.ExtractAllEntries())
+    {
+        reader.WriteAllToDirectory(@"D:\temp", new ExtractionOptions()
+        {
+            ExtractFullPath = true,
+            Overwrite = true
+        });
+    }
+}
+```
+
+### Iterate over all files from a Rar file using RarArchive
 
 ```C#
 using (var archive = RarArchive.Open("Test.rar"))
 {
     foreach (var entry in archive.Entries.Where(entry => !entry.IsDirectory))
     {
-        entry.WriteToDirectory("D:\\temp", new ExtractionOptions()
-        {
-            ExtractFullPath = true,
-            Overwrite = true
-        });
+        Console.WriteLine($"{entry.Key}: {entry.Size} bytes");
     }
 }
 ```

build/Program.cs

@@ -15,7 +15,7 @@ const string Publish = "publish";
 
 Target(
     Clean,
-    ForEach("**/bin", "**/obj"),
+    ["**/bin", "**/obj"],
     dir =>
     {
         IEnumerable<string> GetDirectories(string d)
@@ -44,14 +44,14 @@ Target(
     () =>
     {
         Run("dotnet", "tool restore");
-        Run("dotnet", "csharpier --check .");
+        Run("dotnet", "csharpier check .");
     }
 );
-Target(Restore, DependsOn(Format), () => Run("dotnet", "restore"));
+Target(Restore, [Format], () => Run("dotnet", "restore"));
 
 Target(
     Build,
-    DependsOn(Restore),
+    [Restore],
     () =>
     {
         Run("dotnet", "build src/SharpCompress/SharpCompress.csproj -c Release --no-restore");
@@ -60,8 +60,8 @@ Target(
 
 Target(
     Test,
-    DependsOn(Build),
-    ForEach("net8.0", "net462"),
+    [Build],
+    ["net8.0", "net48"],
     framework =>
     {
         IEnumerable<string> GetFiles(string d)
@@ -69,7 +69,7 @@ Target(
             return Glob.Files(".", d);
         }
 
-        if (!RuntimeInformation.IsOSPlatform(OSPlatform.Windows) && framework == "net462")
+        if (!RuntimeInformation.IsOSPlatform(OSPlatform.Windows) && framework == "net48")
         {
             return;
         }
@@ -83,13 +83,13 @@ Target(
 
 Target(
     Publish,
-    DependsOn(Test),
+    [Test],
     () =>
     {
         Run("dotnet", "pack src/SharpCompress/SharpCompress.csproj -c Release -o artifacts/");
     }
 );
 
-Target("default", DependsOn(Publish), () => Console.WriteLine("Done!"));
+Target("default", [Publish], () => Console.WriteLine("Done!"));
 
 await RunTargetsAndExitAsync(args);

build/build.csproj

@@ -1,14 +1,11 @@
 <Project Sdk="Microsoft.NET.Sdk">
-
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net7.0</TargetFramework>
+    <TargetFramework>net8.0</TargetFramework>
   </PropertyGroup>
-
   <ItemGroup>
-    <PackageReference Include="Bullseye" Version="4.2.1" />
-    <PackageReference Include="Glob" Version="1.1.9" />
-    <PackageReference Include="SimpleExec" Version="11.0.0" />
+    <PackageReference Include="Bullseye" />
+    <PackageReference Include="Glob" />
+    <PackageReference Include="SimpleExec" />
   </ItemGroup>
-
 </Project>

build/packages.lock.json

@@ -0,0 +1,45 @@
+{
+  "version": 2,
+  "dependencies": {
+    "net8.0": {
+      "Bullseye": {
+        "type": "Direct",
+        "requested": "[6.0.0, )",
+        "resolved": "6.0.0",
+        "contentHash": "vgwwXfzs7jJrskWH7saHRMgPzziq/e86QZNWY1MnMxd7e+De7E7EX4K3C7yrvaK9y02SJoLxNxcLG/q5qUAghw=="
+      },
+      "Glob": {
+        "type": "Direct",
+        "requested": "[1.1.9, )",
+        "resolved": "1.1.9",
+        "contentHash": "AfK5+ECWYTP7G3AAdnU8IfVj+QpGjrh9GC2mpdcJzCvtQ4pnerAGwHsxJ9D4/RnhDUz2DSzd951O/lQjQby2Sw=="
+      },
+      "Microsoft.SourceLink.GitHub": {
+        "type": "Direct",
+        "requested": "[8.0.0, )",
+        "resolved": "8.0.0",
+        "contentHash": "G5q7OqtwIyGTkeIOAc3u2ZuV/kicQaec5EaRnc0pIeSnh9LUjj+PYQrJYBURvDt7twGl2PKA7nSN0kz1Zw5bnQ==",
+        "dependencies": {
+          "Microsoft.Build.Tasks.Git": "8.0.0",
+          "Microsoft.SourceLink.Common": "8.0.0"
+        }
+      },
+      "SimpleExec": {
+        "type": "Direct",
+        "requested": "[12.0.0, )",
+        "resolved": "12.0.0",
+        "contentHash": "ptxlWtxC8vM6Y6e3h9ZTxBBkOWnWrm/Sa1HT+2i1xcXY3Hx2hmKDZP5RShPf8Xr9D+ivlrXNy57ktzyH8kyt+Q=="
+      },
+      "Microsoft.Build.Tasks.Git": {
+        "type": "Transitive",
+        "resolved": "8.0.0",
+        "contentHash": "bZKfSIKJRXLTuSzLudMFte/8CempWjVamNUR5eHJizsy+iuOuO/k2gnh7W0dHJmYY0tBf+gUErfluCv5mySAOQ=="
+      },
+      "Microsoft.SourceLink.Common": {
+        "type": "Transitive",
+        "resolved": "8.0.0",
+        "contentHash": "dk9JPxTCIevS75HyEQ0E4OVAFhB2N+V9ShCXf8Q6FkUQZDkgLI12y679Nym1YqsiSysuQskT7Z+6nUf3yab6Vw=="
+      }
+    }
+  }
+}

src/SharpCompress/Algorithms/Adler32.cs

@@ -141,7 +141,7 @@ internal static class Adler32 // From https://github.com/SixLabors/ImageSharp/bl
             4,
             3,
             2,
-            1 // tap2
+            1, // tap2
         };
 #endif
 

src/SharpCompress/Archives/AbstractArchive.cs

@@ -12,39 +12,35 @@ public abstract class AbstractArchive<TEntry, TVolume> : IArchive, IArchiveExtra
     where TEntry : IArchiveEntry
     where TVolume : IVolume
 {
-    private readonly LazyReadOnlyCollection<TVolume> lazyVolumes;
-    private readonly LazyReadOnlyCollection<TEntry> lazyEntries;
+    private readonly LazyReadOnlyCollection<TVolume> _lazyVolumes;
+    private readonly LazyReadOnlyCollection<TEntry> _lazyEntries;
+    private bool _disposed;
+    private readonly SourceStream? _sourceStream;
 
     public event EventHandler<ArchiveExtractionEventArgs<IArchiveEntry>>? EntryExtractionBegin;
     public event EventHandler<ArchiveExtractionEventArgs<IArchiveEntry>>? EntryExtractionEnd;
 
     public event EventHandler<CompressedBytesReadEventArgs>? CompressedBytesRead;
     public event EventHandler<FilePartExtractionBeginEventArgs>? FilePartExtractionBegin;
-
     protected ReaderOptions ReaderOptions { get; }
 
-    private bool disposed;
-    protected SourceStream SrcStream;
-
-    internal AbstractArchive(ArchiveType type, SourceStream srcStream)
+    internal AbstractArchive(ArchiveType type, SourceStream sourceStream)
     {
         Type = type;
-        ReaderOptions = srcStream.ReaderOptions;
-        SrcStream = srcStream;
-        lazyVolumes = new LazyReadOnlyCollection<TVolume>(LoadVolumes(SrcStream));
-        lazyEntries = new LazyReadOnlyCollection<TEntry>(LoadEntries(Volumes));
+        ReaderOptions = sourceStream.ReaderOptions;
+        _sourceStream = sourceStream;
+        _lazyVolumes = new LazyReadOnlyCollection<TVolume>(LoadVolumes(_sourceStream));
+        _lazyEntries = new LazyReadOnlyCollection<TEntry>(LoadEntries(Volumes));
     }
 
-#nullable disable
     internal AbstractArchive(ArchiveType type)
     {
         Type = type;
-        lazyVolumes = new LazyReadOnlyCollection<TVolume>(Enumerable.Empty<TVolume>());
-        lazyEntries = new LazyReadOnlyCollection<TEntry>(Enumerable.Empty<TEntry>());
+        ReaderOptions = new();
+        _lazyVolumes = new LazyReadOnlyCollection<TVolume>(Enumerable.Empty<TVolume>());
+        _lazyEntries = new LazyReadOnlyCollection<TEntry>(Enumerable.Empty<TEntry>());
     }
 
-#nullable enable
-
     public ArchiveType Type { get; }
 
     void IArchiveExtractionListener.FireEntryExtractionBegin(IArchiveEntry entry) =>
@@ -57,7 +53,7 @@ public abstract class AbstractArchive<TEntry, TVolume> : IArchive, IArchiveExtra
     {
         if (!stream.CanSeek || !stream.CanRead)
         {
-            throw new ArgumentException("Archive streams must be Readable and Seekable");
+            throw new ArchiveException("Archive streams must be Readable and Seekable");
         }
         return stream;
     }
@@ -65,12 +61,12 @@ public abstract class AbstractArchive<TEntry, TVolume> : IArchive, IArchiveExtra
     /// <summary>
     /// Returns an ReadOnlyCollection of all the RarArchiveEntries across the one or many parts of the RarArchive.
     /// </summary>
-    public virtual ICollection<TEntry> Entries => lazyEntries;
+    public virtual ICollection<TEntry> Entries => _lazyEntries;
 
     /// <summary>
     /// Returns an ReadOnlyCollection of all the RarArchiveVolumes across the one or many parts of the RarArchive.
     /// </summary>
-    public ICollection<TVolume> Volumes => lazyVolumes;
+    public ICollection<TVolume> Volumes => _lazyVolumes;
 
     /// <summary>
     /// The total size of the files compressed in the archive.
@@ -84,29 +80,29 @@ public abstract class AbstractArchive<TEntry, TVolume> : IArchive, IArchiveExtra
     public virtual long TotalUncompressSize =>
         Entries.Aggregate(0L, (total, cf) => total + cf.Size);
 
-    protected abstract IEnumerable<TVolume> LoadVolumes(SourceStream srcStream);
+    protected abstract IEnumerable<TVolume> LoadVolumes(SourceStream sourceStream);
     protected abstract IEnumerable<TEntry> LoadEntries(IEnumerable<TVolume> volumes);
 
     IEnumerable<IArchiveEntry> IArchive.Entries => Entries.Cast<IArchiveEntry>();
 
-    IEnumerable<IVolume> IArchive.Volumes => lazyVolumes.Cast<IVolume>();
+    IEnumerable<IVolume> IArchive.Volumes => _lazyVolumes.Cast<IVolume>();
 
     public virtual void Dispose()
     {
-        if (!disposed)
+        if (!_disposed)
         {
-            lazyVolumes.ForEach(v => v.Dispose());
-            lazyEntries.GetLoaded().Cast<Entry>().ForEach(x => x.Close());
-            SrcStream?.Dispose();
+            _lazyVolumes.ForEach(v => v.Dispose());
+            _lazyEntries.GetLoaded().Cast<Entry>().ForEach(x => x.Close());
+            _sourceStream?.Dispose();
 
-            disposed = true;
+            _disposed = true;
         }
     }
 
     void IArchiveExtractionListener.EnsureEntriesLoaded()
     {
-        lazyEntries.EnsureFullyLoaded();
-        lazyVolumes.EnsureFullyLoaded();
+        _lazyEntries.EnsureFullyLoaded();
+        _lazyVolumes.EnsureFullyLoaded();
     }
 
     void IExtractionListener.FireCompressedBytesRead(

src/SharpCompress/Archives/AbstractWritableArchive.cs

@@ -41,8 +41,8 @@ public abstract class AbstractWritableArchive<TEntry, TVolume>
     internal AbstractWritableArchive(ArchiveType type)
         : base(type) { }
 
-    internal AbstractWritableArchive(ArchiveType type, SourceStream srcStream)
-        : base(type, srcStream) { }
+    internal AbstractWritableArchive(ArchiveType type, SourceStream sourceStream)
+        : base(type, sourceStream) { }
 
     public override ICollection<TEntry> Entries
     {
@@ -120,6 +120,10 @@ public abstract class AbstractWritableArchive<TEntry, TVolume>
     {
         foreach (var path in Entries.Select(x => x.Key))
         {
+            if (path is null)
+            {
+                continue;
+            }
             var p = path.Replace('/', '\\');
             if (p.Length > 0 && p[0] == '\\')
             {
@@ -147,7 +151,7 @@ public abstract class AbstractWritableArchive<TEntry, TVolume>
     {
         if (!source.CanRead || !source.CanSeek)
         {
-            throw new ArgumentException(
+            throw new ArchiveException(
                 "Streams must be readable and seekable to use the Writing Archive API"
             );
         }

src/SharpCompress/Archives/ArchiveFactory.cs

@@ -122,10 +122,7 @@ public static class ArchiveFactory
     )
     {
         using var archive = Open(sourceArchive);
-        foreach (var entry in archive.Entries)
-        {
-            entry.WriteToDirectory(destinationDirectory, options);
-        }
+        archive.WriteToDirectory(destinationDirectory, options);
     }
 
     private static T FindFactory<T>(FileInfo finfo)
@@ -189,9 +186,10 @@ public static class ArchiveFactory
 
         foreach (var factory in Factory.Factories)
         {
+            var isArchive = factory.IsArchive(stream);
             stream.Position = startPosition;
 
-            if (factory.IsArchive(stream, null))
+            if (isArchive)
             {
                 type = factory.KnownArchiveType;
                 return true;
@@ -239,4 +237,6 @@ public static class ArchiveFactory
             }
         }
     }
+
+    public static IArchiveFactory AutoFactory { get; } = new AutoArchiveFactory();
 }

src/SharpCompress/Archives/AutoArchiveFactory.cs

@@ -0,0 +1,27 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using SharpCompress.Common;
+using SharpCompress.Readers;
+
+namespace SharpCompress.Archives;
+
+class AutoArchiveFactory : IArchiveFactory
+{
+    public string Name => nameof(AutoArchiveFactory);
+
+    public ArchiveType? KnownArchiveType => null;
+
+    public IEnumerable<string> GetSupportedExtensions() => throw new NotSupportedException();
+
+    public bool IsArchive(Stream stream, string? password = null) =>
+        throw new NotSupportedException();
+
+    public FileInfo? GetFilePart(int index, FileInfo part1) => throw new NotSupportedException();
+
+    public IArchive Open(Stream stream, ReaderOptions? readerOptions = null) =>
+        ArchiveFactory.Open(stream, readerOptions);
+
+    public IArchive Open(FileInfo fileInfo, ReaderOptions? readerOptions = null) =>
+        ArchiveFactory.Open(fileInfo, readerOptions);
+}

src/SharpCompress/Archives/GZip/GZipArchive.cs

@@ -90,7 +90,7 @@ public class GZipArchive : AbstractWritableArchive<GZipArchiveEntry, GZipVolume>
     {
         stream.CheckNotNull(nameof(stream));
         return new GZipArchive(
-            new SourceStream(stream, i => null, readerOptions ?? new ReaderOptions())
+            new SourceStream(stream, _ => null, readerOptions ?? new ReaderOptions())
         );
     }
 
@@ -99,16 +99,14 @@ public class GZipArchive : AbstractWritableArchive<GZipArchiveEntry, GZipVolume>
     /// <summary>
     /// Constructor with a SourceStream able to handle FileInfo and Streams.
     /// </summary>
-    /// <param name="srcStream"></param>
-    /// <param name="options"></param>
-    internal GZipArchive(SourceStream srcStream)
-        : base(ArchiveType.Tar, srcStream) { }
+    /// <param name="sourceStream"></param>
+    private GZipArchive(SourceStream sourceStream)
+        : base(ArchiveType.GZip, sourceStream) { }
 
-    protected override IEnumerable<GZipVolume> LoadVolumes(SourceStream srcStream)
+    protected override IEnumerable<GZipVolume> LoadVolumes(SourceStream sourceStream)
     {
-        srcStream.LoadAllParts();
-        var idx = 0;
-        return srcStream.Streams.Select(a => new GZipVolume(a, ReaderOptions, idx++));
+        sourceStream.LoadAllParts();
+        return sourceStream.Streams.Select(a => new GZipVolume(a, ReaderOptions, 0));
     }
 
     public static bool IsGZipFile(string filePath) => IsGZipFile(new FileInfo(filePath));
@@ -164,7 +162,7 @@ public class GZipArchive : AbstractWritableArchive<GZipArchiveEntry, GZipVolume>
     {
         if (Entries.Any())
         {
-            throw new InvalidOperationException("Only one entry is allowed in a GZip Archive");
+            throw new InvalidFormatException("Only one entry is allowed in a GZip Archive");
         }
         return new GZipWritableArchiveEntry(this, source, filePath, size, modified, closeStream);
     }
@@ -178,13 +176,17 @@ public class GZipArchive : AbstractWritableArchive<GZipArchiveEntry, GZipVolume>
     {
         if (Entries.Count > 1)
         {
-            throw new InvalidOperationException("Only one entry is allowed in a GZip Archive");
+            throw new InvalidFormatException("Only one entry is allowed in a GZip Archive");
         }
         using var writer = new GZipWriter(stream, new GZipWriterOptions(options));
         foreach (var entry in oldEntries.Concat(newEntries).Where(x => !x.IsDirectory))
         {
             using var entryStream = entry.OpenEntryStream();
-            writer.Write(entry.Key, entryStream, entry.LastModifiedTime);
+            writer.Write(
+                entry.Key.NotNull("Entry Key is null"),
+                entryStream,
+                entry.LastModifiedTime
+            );
         }
     }
 

src/SharpCompress/Archives/GZip/GZipArchiveEntry.cs

@@ -6,7 +6,7 @@ namespace SharpCompress.Archives.GZip;
 
 public class GZipArchiveEntry : GZipEntry, IArchiveEntry
 {
-    internal GZipArchiveEntry(GZipArchive archive, GZipFilePart part)
+    internal GZipArchiveEntry(GZipArchive archive, GZipFilePart? part)
         : base(part) => Archive = archive;
 
     public virtual Stream OpenEntryStream()
@@ -17,7 +17,7 @@ public class GZipArchiveEntry : GZipEntry, IArchiveEntry
         {
             part.GetRawStream().Position = part.EntryStartPosition;
         }
-        return Parts.Single().GetCompressedStream();
+        return Parts.Single().GetCompressedStream().NotNull();
     }
 
     #region IArchiveEntry Members

src/SharpCompress/Archives/GZip/GZipWritableArchiveEntry.cs

@@ -1,5 +1,3 @@
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using System.IO;
@@ -32,7 +30,7 @@ internal sealed class GZipWritableArchiveEntry : GZipArchiveEntry, IWritableArch
 
     public override long Crc => 0;
 
-    public override string Key { get; }
+    public override string? Key { get; }
 
     public override long CompressedSize => 0;
 

src/SharpCompress/Archives/IArchiveEntryExtensions.cs

@@ -17,15 +17,11 @@ public static class IArchiveEntryExtensions
         streamListener.EnsureEntriesLoaded();
         streamListener.FireEntryExtractionBegin(archiveEntry);
         streamListener.FireFilePartExtractionBegin(
-            archiveEntry.Key,
+            archiveEntry.Key ?? "Key",
             archiveEntry.Size,
             archiveEntry.CompressedSize
         );
         var entryStream = archiveEntry.OpenEntryStream();
-        if (entryStream is null)
-        {
-            return;
-        }
         using (entryStream)
         {
             using Stream s = new ListeningStream(streamListener, entryStream);

src/SharpCompress/Archives/IArchiveExtensions.cs

@@ -3,8 +3,8 @@ using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using System.Threading;
-using System.Threading.Tasks;
 using SharpCompress.Common;
+using SharpCompress.Readers;
 
 namespace SharpCompress.Archives;
 
@@ -19,10 +19,8 @@ public static class IArchiveExtensions
         ExtractionOptions? options = null
     )
     {
-        foreach (var entry in archive.Entries.Where(x => !x.IsDirectory))
-        {
-            entry.WriteToDirectory(destinationDirectory, options);
-        }
+        using var reader = archive.ExtractAllEntries();
+        reader.WriteAllToDirectory(destinationDirectory, options);
     }
 
     /// <summary>
@@ -55,14 +53,26 @@ public static class IArchiveExtensions
             var entry = entries.Entry;
             if (entry.IsDirectory)
             {
+                var dirPath = Path.Combine(destination, entry.Key.NotNull("Entry Key is null"));
+                if (
+                    Path.GetDirectoryName(dirPath + "/") is { } emptyDirectory
+                    && seenDirectories.Add(dirPath)
+                )
+                {
+                    Directory.CreateDirectory(emptyDirectory);
+                }
                 continue;
             }
 
-            // Create each directory
-            var path = Path.Combine(destination, entry.Key);
-            if (Path.GetDirectoryName(path) is { } directory && seenDirectories.Add(path))
+            // Create each directory if not already created
+            var path = Path.Combine(destination, entry.Key.NotNull("Entry Key is null"));
+            if (Path.GetDirectoryName(path) is { } directory)
             {
-                Directory.CreateDirectory(directory);
+                if (!Directory.Exists(directory) && !seenDirectories.Contains(directory))
+                {
+                    Directory.CreateDirectory(directory);
+                    seenDirectories.Add(directory);
+                }
             }
 
             // Write file

src/SharpCompress/Archives/Rar/FileInfoRarArchiveVolume.cs

@@ -1,4 +1,5 @@
 using System.Collections.Generic;
+using System.Collections.ObjectModel;
 using System.IO;
 using System.Linq;
 using SharpCompress.Common.Rar;
@@ -13,7 +14,7 @@ namespace SharpCompress.Archives.Rar;
 /// </summary>
 internal class FileInfoRarArchiveVolume : RarVolume
 {
-    internal FileInfoRarArchiveVolume(FileInfo fileInfo, ReaderOptions options, int index = 0)
+    internal FileInfoRarArchiveVolume(FileInfo fileInfo, ReaderOptions options, int index)
         : base(StreamingMode.Seekable, fileInfo.OpenRead(), FixOptions(options), index)
     {
         FileInfo = fileInfo;

src/SharpCompress/Archives/Rar/RarArchive.cs

@@ -14,6 +14,7 @@ namespace SharpCompress.Archives.Rar;
 
 public class RarArchive : AbstractArchive<RarArchiveEntry, RarVolume>
 {
+    private bool _disposed;
     internal Lazy<IRarUnpack> UnpackV2017 { get; } =
         new(() => new Compressors.Rar.UnpackV2017.Unpack());
     internal Lazy<IRarUnpack> UnpackV1 { get; } = new(() => new Compressors.Rar.UnpackV1.Unpack());
@@ -21,39 +22,61 @@ public class RarArchive : AbstractArchive<RarArchiveEntry, RarVolume>
     /// <summary>
     /// Constructor with a SourceStream able to handle FileInfo and Streams.
     /// </summary>
-    /// <param name="srcStream"></param>
-    /// <param name="options"></param>
-    internal RarArchive(SourceStream srcStream)
-        : base(ArchiveType.Rar, srcStream) { }
+    /// <param name="sourceStream"></param>
+    private RarArchive(SourceStream sourceStream)
+        : base(ArchiveType.Rar, sourceStream) { }
+
+    public override void Dispose()
+    {
+        if (!_disposed)
+        {
+            if (UnpackV1.IsValueCreated && UnpackV1.Value is IDisposable unpackV1)
+            {
+                unpackV1.Dispose();
+            }
+
+            _disposed = true;
+            base.Dispose();
+        }
+    }
 
     protected override IEnumerable<RarArchiveEntry> LoadEntries(IEnumerable<RarVolume> volumes) =>
         RarArchiveEntryFactory.GetEntries(this, volumes, ReaderOptions);
 
-    protected override IEnumerable<RarVolume> LoadVolumes(SourceStream srcStream)
+    protected override IEnumerable<RarVolume> LoadVolumes(SourceStream sourceStream)
     {
-        SrcStream.LoadAllParts(); //request all streams
-        var streams = SrcStream.Streams.ToArray();
-        var idx = 0;
+        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
         {
-            SrcStream.IsVolumes = true;
+            sourceStream.IsVolumes = true;
             streams[1].Position = 0;
-            SrcStream.Position = 0;
+            sourceStream.Position = 0;
 
-            return srcStream.Streams.Select(a => new StreamRarArchiveVolume(
+            return sourceStream.Streams.Select(a => new StreamRarArchiveVolume(
                 a,
                 ReaderOptions,
-                idx++
+                i++
             ));
         }
-        else //split mode or single file
-        {
-            return new StreamRarArchiveVolume(SrcStream, ReaderOptions, idx++).AsEnumerable();
-        }
+
+        //split mode or single file
+        return new StreamRarArchiveVolume(sourceStream, ReaderOptions, i++).AsEnumerable();
     }
 
     protected override IReader CreateReaderForSolidExtraction()
     {
+        if (this.IsMultipartVolume())
+        {
+            var streams = Volumes.Select(volume =>
+            {
+                volume.Stream.Position = 0;
+                return volume.Stream;
+            });
+            return RarReader.Open(streams, ReaderOptions);
+        }
+
         var stream = Volumes.First().Stream;
         stream.Position = 0;
         return RarReader.Open(stream, ReaderOptions);
@@ -108,7 +131,7 @@ public class RarArchive : AbstractArchive<RarArchiveEntry, RarVolume>
     public static RarArchive Open(Stream stream, ReaderOptions? options = null)
     {
         stream.CheckNotNull(nameof(stream));
-        return new RarArchive(new SourceStream(stream, i => null, options ?? new ReaderOptions()));
+        return new RarArchive(new SourceStream(stream, _ => null, options ?? new ReaderOptions()));
     }
 
     /// <summary>

src/SharpCompress/Archives/Rar/RarArchiveEntry.cs

@@ -42,7 +42,7 @@ public class RarArchiveEntry : RarEntry, IArchiveEntry
         {
             CheckIncomplete();
             return BitConverter.ToUInt32(
-                parts.Select(fp => fp.FileHeader).Single(fh => !fh.IsSplitAfter).FileCrc,
+                parts.Select(fp => fp.FileHeader).Single(fh => !fh.IsSplitAfter).FileCrc.NotNull(),
                 0
             );
         }

src/SharpCompress/Archives/Rar/SeekableFilePart.cs

@@ -6,8 +6,8 @@ namespace SharpCompress.Archives.Rar;
 
 internal class SeekableFilePart : RarFilePart
 {
-    private readonly Stream stream;
-    private readonly string? password;
+    private readonly Stream _stream;
+    private readonly string? _password;
 
     internal SeekableFilePart(
         MarkHeader mh,
@@ -18,27 +18,27 @@ internal class SeekableFilePart : RarFilePart
     )
         : base(mh, fh, index)
     {
-        this.stream = stream;
-        this.password = password;
+        _stream = stream;
+        _password = password;
     }
 
     internal override Stream GetCompressedStream()
     {
-        stream.Position = FileHeader.DataStartPosition;
+        _stream.Position = FileHeader.DataStartPosition;
 
         if (FileHeader.R4Salt != null)
         {
-            var cryptKey = new CryptKey3(password!);
-            return new RarCryptoWrapper(stream, FileHeader.R4Salt, cryptKey);
+            var cryptKey = new CryptKey3(_password!);
+            return new RarCryptoWrapper(_stream, FileHeader.R4Salt, cryptKey);
         }
 
         if (FileHeader.Rar5CryptoInfo != null)
         {
-            var cryptKey = new CryptKey5(password!, FileHeader.Rar5CryptoInfo);
-            return new RarCryptoWrapper(stream, FileHeader.Rar5CryptoInfo.Salt, cryptKey);
+            var cryptKey = new CryptKey5(_password!, FileHeader.Rar5CryptoInfo);
+            return new RarCryptoWrapper(_stream, FileHeader.Rar5CryptoInfo.Salt, cryptKey);
         }
 
-        return stream;
+        return _stream;
     }
 
     internal override string FilePartName => "Unknown Stream - File Entry: " + FileHeader.FileName;

src/SharpCompress/Archives/Rar/StreamRarArchiveVolume.cs

@@ -9,7 +9,7 @@ namespace SharpCompress.Archives.Rar;
 
 internal class StreamRarArchiveVolume : RarVolume
 {
-    internal StreamRarArchiveVolume(Stream stream, ReaderOptions options, int index = 0)
+    internal StreamRarArchiveVolume(Stream stream, ReaderOptions options, int index)
         : base(StreamingMode.Seekable, stream, options, index) { }
 
     internal override IEnumerable<RarFilePart> ReadFileParts() => GetVolumeFileParts();

src/SharpCompress/Archives/SevenZip/SevenZipArchive.cs

@@ -1,5 +1,3 @@
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using System.IO;
@@ -14,14 +12,14 @@ namespace SharpCompress.Archives.SevenZip;
 
 public class SevenZipArchive : AbstractArchive<SevenZipArchiveEntry, SevenZipVolume>
 {
-    private ArchiveDatabase database;
+    private ArchiveDatabase? _database;
 
     /// <summary>
     /// Constructor expects a filepath to an existing file.
     /// </summary>
     /// <param name="filePath"></param>
     /// <param name="readerOptions"></param>
-    public static SevenZipArchive Open(string filePath, ReaderOptions readerOptions = null)
+    public static SevenZipArchive Open(string filePath, ReaderOptions? readerOptions = null)
     {
         filePath.CheckNotNullOrEmpty("filePath");
         return Open(new FileInfo(filePath), readerOptions ?? new ReaderOptions());
@@ -32,7 +30,7 @@ public class SevenZipArchive : AbstractArchive<SevenZipArchiveEntry, SevenZipVol
     /// </summary>
     /// <param name="fileInfo"></param>
     /// <param name="readerOptions"></param>
-    public static SevenZipArchive Open(FileInfo fileInfo, ReaderOptions readerOptions = null)
+    public static SevenZipArchive Open(FileInfo fileInfo, ReaderOptions? readerOptions = null)
     {
         fileInfo.CheckNotNull("fileInfo");
         return new SevenZipArchive(
@@ -51,7 +49,7 @@ public class SevenZipArchive : AbstractArchive<SevenZipArchiveEntry, SevenZipVol
     /// <param name="readerOptions"></param>
     public static SevenZipArchive Open(
         IEnumerable<FileInfo> fileInfos,
-        ReaderOptions readerOptions = null
+        ReaderOptions? readerOptions = null
     )
     {
         fileInfos.CheckNotNull(nameof(fileInfos));
@@ -72,7 +70,7 @@ public class SevenZipArchive : AbstractArchive<SevenZipArchiveEntry, SevenZipVol
     /// <param name="readerOptions"></param>
     public static SevenZipArchive Open(
         IEnumerable<Stream> streams,
-        ReaderOptions readerOptions = null
+        ReaderOptions? readerOptions = null
     )
     {
         streams.CheckNotNull(nameof(streams));
@@ -91,27 +89,25 @@ public class SevenZipArchive : AbstractArchive<SevenZipArchiveEntry, SevenZipVol
     /// </summary>
     /// <param name="stream"></param>
     /// <param name="readerOptions"></param>
-    public static SevenZipArchive Open(Stream stream, ReaderOptions readerOptions = null)
+    public static SevenZipArchive Open(Stream stream, ReaderOptions? readerOptions = null)
     {
         stream.CheckNotNull("stream");
         return new SevenZipArchive(
-            new SourceStream(stream, i => null, readerOptions ?? new ReaderOptions())
+            new SourceStream(stream, _ => null, readerOptions ?? new ReaderOptions())
         );
     }
 
     /// <summary>
     /// Constructor with a SourceStream able to handle FileInfo and Streams.
     /// </summary>
-    /// <param name="srcStream"></param>
-    /// <param name="options"></param>
-    internal SevenZipArchive(SourceStream srcStream)
-        : base(ArchiveType.SevenZip, srcStream) { }
+    /// <param name="sourceStream"></param>
+    private SevenZipArchive(SourceStream sourceStream)
+        : base(ArchiveType.SevenZip, sourceStream) { }
 
-    protected override IEnumerable<SevenZipVolume> LoadVolumes(SourceStream srcStream)
+    protected override IEnumerable<SevenZipVolume> LoadVolumes(SourceStream sourceStream)
     {
-        SrcStream.LoadAllParts(); //request all streams
-        var idx = 0;
-        return new SevenZipVolume(srcStream, ReaderOptions, idx++).AsEnumerable(); //simple single volume or split, multivolume not supported
+        sourceStream.NotNull("SourceStream is null").LoadAllParts(); //request all streams
+        return new SevenZipVolume(sourceStream, ReaderOptions, 0).AsEnumerable(); //simple single volume or split, multivolume not supported
     }
 
     public static bool IsSevenZipFile(string filePath) => IsSevenZipFile(new FileInfo(filePath));
@@ -135,13 +131,17 @@ public class SevenZipArchive : AbstractArchive<SevenZipArchiveEntry, SevenZipVol
     {
         var stream = volumes.Single().Stream;
         LoadFactory(stream);
-        var entries = new SevenZipArchiveEntry[database._files.Count];
-        for (var i = 0; i < database._files.Count; i++)
+        if (_database is null)
         {
-            var file = database._files[i];
+            return Enumerable.Empty<SevenZipArchiveEntry>();
+        }
+        var entries = new SevenZipArchiveEntry[_database._files.Count];
+        for (var i = 0; i < _database._files.Count; i++)
+        {
+            var file = _database._files[i];
             entries[i] = new SevenZipArchiveEntry(
                 this,
-                new SevenZipFilePart(stream, database, i, file, ReaderOptions.ArchiveEncoding)
+                new SevenZipFilePart(stream, _database, i, file, ReaderOptions.ArchiveEncoding)
             );
         }
         foreach (var group in entries.Where(x => !x.IsDirectory).GroupBy(x => x.FilePart.Folder))
@@ -159,12 +159,12 @@ public class SevenZipArchive : AbstractArchive<SevenZipArchiveEntry, SevenZipVol
 
     private void LoadFactory(Stream stream)
     {
-        if (database is null)
+        if (_database is null)
         {
             stream.Position = 0;
             var reader = new ArchiveReader();
-            reader.Open(stream);
-            database = reader.ReadDatabase(new PasswordProvider(ReaderOptions.Password));
+            reader.Open(stream, lookForHeader: ReaderOptions.LookForHeader);
+            _database = reader.ReadDatabase(new PasswordProvider(ReaderOptions.Password));
         }
     }
 
@@ -180,14 +180,14 @@ public class SevenZipArchive : AbstractArchive<SevenZipArchiveEntry, SevenZipVol
         }
     }
 
-    private static ReadOnlySpan<byte> SIGNATURE =>
+    private static ReadOnlySpan<byte> Signature =>
         new byte[] { (byte)'7', (byte)'z', 0xBC, 0xAF, 0x27, 0x1C };
 
     private static bool SignatureMatch(Stream stream)
     {
         var reader = new BinaryReader(stream);
         ReadOnlySpan<byte> signatureBytes = reader.ReadBytes(6);
-        return signatureBytes.SequenceEqual(SIGNATURE);
+        return signatureBytes.SequenceEqual(Signature);
     }
 
     protected override IReader CreateReaderForSolidExtraction() =>
@@ -196,30 +196,24 @@ public class SevenZipArchive : AbstractArchive<SevenZipArchiveEntry, SevenZipVol
     public override bool IsSolid =>
         Entries.Where(x => !x.IsDirectory).GroupBy(x => x.FilePart.Folder).Count() > 1;
 
-    public override long TotalSize
-    {
-        get
-        {
-            var i = Entries.Count;
-            return database._packSizes.Aggregate(0L, (total, packSize) => total + packSize);
-        }
-    }
+    public override long TotalSize =>
+        _database?._packSizes.Aggregate(0L, (total, packSize) => total + packSize) ?? 0;
 
     private sealed class SevenZipReader : AbstractReader<SevenZipEntry, SevenZipVolume>
     {
-        private readonly SevenZipArchive archive;
-        private CFolder currentFolder;
-        private Stream currentStream;
-        private CFileItem currentItem;
+        private readonly SevenZipArchive _archive;
+        private CFolder? _currentFolder;
+        private Stream? _currentStream;
+        private CFileItem? _currentItem;
 
         internal SevenZipReader(ReaderOptions readerOptions, SevenZipArchive archive)
-            : base(readerOptions, ArchiveType.SevenZip) => this.archive = archive;
+            : base(readerOptions, ArchiveType.SevenZip) => this._archive = archive;
 
-        public override SevenZipVolume Volume => archive.Volumes.Single();
+        public override SevenZipVolume Volume => _archive.Volumes.Single();
 
         protected override IEnumerable<SevenZipEntry> GetEntries(Stream stream)
         {
-            var entries = archive.Entries.ToList();
+            var entries = _archive.Entries.ToList();
             stream.Position = 0;
             foreach (var dir in entries.Where(x => x.IsDirectory))
             {
@@ -229,37 +223,42 @@ public class SevenZipArchive : AbstractArchive<SevenZipArchiveEntry, SevenZipVol
                 var group in entries.Where(x => !x.IsDirectory).GroupBy(x => x.FilePart.Folder)
             )
             {
-                currentFolder = group.Key;
+                _currentFolder = group.Key;
                 if (group.Key is null)
                 {
-                    currentStream = Stream.Null;
+                    _currentStream = Stream.Null;
                 }
                 else
                 {
-                    currentStream = archive.database.GetFolderStream(
+                    _currentStream = _archive._database?.GetFolderStream(
                         stream,
-                        currentFolder,
+                        _currentFolder,
                         new PasswordProvider(Options.Password)
                     );
                 }
                 foreach (var entry in group)
                 {
-                    currentItem = entry.FilePart.Header;
+                    _currentItem = entry.FilePart.Header;
                     yield return entry;
                 }
             }
         }
 
         protected override EntryStream GetEntryStream() =>
-            CreateEntryStream(new ReadOnlySubStream(currentStream, currentItem.Size));
+            CreateEntryStream(
+                new ReadOnlySubStream(
+                    _currentStream.NotNull("currentStream is not null"),
+                    _currentItem?.Size ?? 0
+                )
+            );
     }
 
     private class PasswordProvider : IPasswordProvider
     {
-        private readonly string _password;
+        private readonly string? _password;
 
-        public PasswordProvider(string password) => _password = password;
+        public PasswordProvider(string? password) => _password = password;
 
-        public string CryptoGetTextPassword() => _password;
+        public string? CryptoGetTextPassword() => _password;
     }
 }

src/SharpCompress/Archives/Tar/TarArchive.cs

@@ -114,7 +114,7 @@ public class TarArchive : AbstractWritableArchive<TarArchiveEntry, TarVolume>
             var tarHeader = new TarHeader(new ArchiveEncoding());
             var readSucceeded = tarHeader.Read(new BinaryReader(stream));
             var isEmptyArchive =
-                tarHeader.Name.Length == 0
+                tarHeader.Name?.Length == 0
                 && tarHeader.Size == 0
                 && Enum.IsDefined(typeof(EntryType), tarHeader.EntryType);
             return readSucceeded || isEmptyArchive;
@@ -123,22 +123,20 @@ public class TarArchive : AbstractWritableArchive<TarArchiveEntry, TarVolume>
         return false;
     }
 
-    protected override IEnumerable<TarVolume> LoadVolumes(SourceStream srcStream)
+    protected override IEnumerable<TarVolume> LoadVolumes(SourceStream sourceStream)
     {
-        SrcStream.LoadAllParts(); //request all streams
-        var idx = 0;
-        return new TarVolume(srcStream, ReaderOptions, idx++).AsEnumerable(); //simple single volume or split, multivolume not supported
+        sourceStream.NotNull("SourceStream is null").LoadAllParts(); //request all streams
+        return new TarVolume(sourceStream, ReaderOptions, 1).AsEnumerable(); //simple single volume or split, multivolume not supported
     }
 
     /// <summary>
     /// Constructor with a SourceStream able to handle FileInfo and Streams.
     /// </summary>
-    /// <param name="srcStream"></param>
-    /// <param name="options"></param>
-    internal TarArchive(SourceStream srcStream)
-        : base(ArchiveType.Tar, srcStream) { }
+    /// <param name="sourceStream"></param>
+    private TarArchive(SourceStream sourceStream)
+        : base(ArchiveType.Tar, sourceStream) { }
 
-    internal TarArchive()
+    private TarArchive()
         : base(ArchiveType.Tar) { }
 
     protected override IEnumerable<TarArchiveEntry> LoadEntries(IEnumerable<TarVolume> volumes)
@@ -192,6 +190,10 @@ public class TarArchive : AbstractWritableArchive<TarArchiveEntry, TarVolume>
                     );
                 }
             }
+            else
+            {
+                throw new IncompleteArchiveException("Failed to read TAR header");
+            }
         }
     }
 
@@ -225,7 +227,12 @@ public class TarArchive : AbstractWritableArchive<TarArchiveEntry, TarVolume>
         foreach (var entry in oldEntries.Concat(newEntries).Where(x => !x.IsDirectory))
         {
             using var entryStream = entry.OpenEntryStream();
-            writer.Write(entry.Key, entryStream, entry.LastModifiedTime, entry.Size);
+            writer.Write(
+                entry.Key.NotNull("Entry Key is null"),
+                entryStream,
+                entry.LastModifiedTime,
+                entry.Size
+            );
         }
     }
 

src/SharpCompress/Archives/Tar/TarArchiveEntry.cs

@@ -7,10 +7,10 @@ namespace SharpCompress.Archives.Tar;
 
 public class TarArchiveEntry : TarEntry, IArchiveEntry
 {
-    internal TarArchiveEntry(TarArchive archive, TarFilePart part, CompressionType compressionType)
+    internal TarArchiveEntry(TarArchive archive, TarFilePart? part, CompressionType compressionType)
         : base(part, compressionType) => Archive = archive;
 
-    public virtual Stream OpenEntryStream() => Parts.Single().GetCompressedStream();
+    public virtual Stream OpenEntryStream() => Parts.Single().GetCompressedStream().NotNull();
 
     #region IArchiveEntry Members
 

src/SharpCompress/Archives/Tar/TarWritableArchiveEntry.cs

@@ -1,5 +1,3 @@
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using System.IO;

src/SharpCompress/Archives/Zip/ZipArchive.cs

@@ -16,10 +16,7 @@ namespace SharpCompress.Archives.Zip;
 
 public class ZipArchive : AbstractWritableArchive<ZipArchiveEntry, ZipVolume>
 {
-#nullable disable
-    private readonly SeekableZipHeaderFactory headerFactory;
-
-#nullable enable
+    private readonly SeekableZipHeaderFactory? headerFactory;
 
     /// <summary>
     /// Gets or sets the compression level applied to files added to the archive,
@@ -30,13 +27,13 @@ public class ZipArchive : AbstractWritableArchive<ZipArchiveEntry, ZipVolume>
     /// <summary>
     /// Constructor with a SourceStream able to handle FileInfo and Streams.
     /// </summary>
-    /// <param name="srcStream"></param>
+    /// <param name="sourceStream"></param>
     /// <param name="options"></param>
-    internal ZipArchive(SourceStream srcStream)
-        : base(ArchiveType.Zip, srcStream) =>
+    internal ZipArchive(SourceStream sourceStream)
+        : base(ArchiveType.Zip, sourceStream) =>
         headerFactory = new SeekableZipHeaderFactory(
-            srcStream.ReaderOptions.Password,
-            srcStream.ReaderOptions.ArchiveEncoding
+            sourceStream.ReaderOptions.Password,
+            sourceStream.ReaderOptions.ArchiveEncoding
         );
 
     /// <summary>
@@ -189,21 +186,21 @@ public class ZipArchive : AbstractWritableArchive<ZipArchiveEntry, ZipVolume>
         }
     }
 
-    protected override IEnumerable<ZipVolume> LoadVolumes(SourceStream srcStream)
+    protected override IEnumerable<ZipVolume> LoadVolumes(SourceStream stream)
     {
-        SrcStream.LoadAllParts(); //request all streams
-        SrcStream.Position = 0;
+        stream.LoadAllParts(); //request all streams
+        stream.Position = 0;
 
-        var streams = SrcStream.Streams.ToList();
+        var streams = stream.Streams.ToList();
         var idx = 0;
-        if (streams.Count > 1) //test part 2 - true = multipart not split
+        if (streams.Count() > 1) //test part 2 - true = multipart not split
         {
             streams[1].Position += 4; //skip the POST_DATA_DESCRIPTOR to prevent an exception
             var isZip = IsZipFile(streams[1], ReaderOptions.Password);
             streams[1].Position -= 4;
             if (isZip)
             {
-                SrcStream.IsVolumes = true;
+                stream.IsVolumes = true;
 
                 var tmp = streams[0]; //arcs as zip, z01 ... swap the zip the end
                 streams.RemoveAt(0);
@@ -215,7 +212,7 @@ public class ZipArchive : AbstractWritableArchive<ZipArchiveEntry, ZipVolume>
         }
 
         //split mode or single file
-        return new ZipVolume(SrcStream, ReaderOptions, idx++).AsEnumerable();
+        return new ZipVolume(stream, ReaderOptions, idx++).AsEnumerable();
     }
 
     internal ZipArchive()
@@ -224,14 +221,13 @@ public class ZipArchive : AbstractWritableArchive<ZipArchiveEntry, ZipVolume>
     protected override IEnumerable<ZipArchiveEntry> LoadEntries(IEnumerable<ZipVolume> volumes)
     {
         var vols = volumes.ToArray();
-        foreach (var h in headerFactory.ReadSeekableHeader(vols.Last().Stream))
+        foreach (var h in headerFactory.NotNull().ReadSeekableHeader(vols.Last().Stream))
         {
             if (h != null)
             {
                 switch (h.ZipHeaderType)
                 {
                     case ZipHeaderType.DirectoryEntry:
-
                         {
                             var deh = (DirectoryEntryHeader)h;
                             Stream s;
@@ -254,14 +250,14 @@ public class ZipArchive : AbstractWritableArchive<ZipArchiveEntry, ZipVolume>
 
                             yield return new ZipArchiveEntry(
                                 this,
-                                new SeekableZipFilePart(headerFactory, deh, s)
+                                new SeekableZipFilePart(headerFactory.NotNull(), deh, s)
                             );
                         }
                         break;
                     case ZipHeaderType.DirectoryEnd:
                     {
                         var bytes = ((DirectoryEndHeader)h).Comment ?? Array.Empty<byte>();
-                        volumes.Last().Comment = ReaderOptions.ArchiveEncoding.Decode(bytes);
+                        vols.Last().Comment = ReaderOptions.ArchiveEncoding.Decode(bytes);
                         yield break;
                     }
                 }
@@ -282,7 +278,11 @@ public class ZipArchive : AbstractWritableArchive<ZipArchiveEntry, ZipVolume>
         foreach (var entry in oldEntries.Concat(newEntries).Where(x => !x.IsDirectory))
         {
             using var entryStream = entry.OpenEntryStream();
-            writer.Write(entry.Key, entryStream, entry.LastModifiedTime);
+            writer.Write(
+                entry.Key.NotNull("Entry Key is null"),
+                entryStream,
+                entry.LastModifiedTime
+            );
         }
     }
 

src/SharpCompress/Archives/Zip/ZipArchiveEntry.cs

@@ -9,7 +9,7 @@ public class ZipArchiveEntry : ZipEntry, IArchiveEntry
     internal ZipArchiveEntry(ZipArchive archive, SeekableZipFilePart? part)
         : base(part) => Archive = archive;
 
-    public virtual Stream OpenEntryStream() => Parts.Single().GetCompressedStream();
+    public virtual Stream OpenEntryStream() => Parts.Single().GetCompressedStream().NotNull();
 
     #region IArchiveEntry Members
 

src/SharpCompress/AssemblyInfo.cs

@@ -1,3 +1,7 @@
 using System;
+using System.Runtime.CompilerServices;
 
 [assembly: CLSCompliant(true)]
+[assembly: InternalsVisibleTo(
+    "SharpCompress.Test,PublicKey=0024000004800000940000000602000000240000525341310004000001000100158bebf1433f76dffc356733c138babea7a47536c65ed8009b16372c6f4edbb20554db74a62687f56b97c20a6ce8c4b123280279e33c894e7b3aa93ab3c573656fde4db576cfe07dba09619ead26375b25d2c4a8e43f7be257d712b0dd2eb546f67adb09281338618a58ac834fc038dd7e2740a7ab3591826252e4f4516306dc"
+)]

src/SharpCompress/BufferPool.cs

@@ -1,33 +0,0 @@
-using System.Buffers;
-
-namespace SharpCompress;
-
-internal static class BufferPool
-{
-    /// <summary>
-    ///     gets a buffer from the pool
-    /// </summary>
-    /// <param name="bufferSize">size of the buffer</param>
-    /// <returns>the buffer</returns>
-    public static byte[] Rent(int bufferSize)
-    {
-#if NETCOREAPP || NETSTANDARD2_1_OR_GREATER
-        return ArrayPool<byte>.Shared.Rent(bufferSize);
-#else
-        return new byte[bufferSize];
-#endif
-    }
-
-    /// <summary>
-    ///     returns a buffer to the pool
-    /// </summary>
-    /// <param name="buffer">the buffer to return</param>
-    public static void Return(byte[] buffer)
-    {
-#if NETCOREAPP || NETSTANDARD2_1_OR_GREATER
-        ArrayPool<byte>.Shared.Return(buffer);
-#else
-        // no-op
-#endif
-    }
-}

src/SharpCompress/Common/Arc/ArcEntry.cs

@@ -0,0 +1,60 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using SharpCompress.Common.GZip;
+using SharpCompress.Common.Tar;
+
+namespace SharpCompress.Common.Arc
+{
+    public class ArcEntry : Entry
+    {
+        private readonly ArcFilePart? _filePart;
+
+        internal ArcEntry(ArcFilePart? filePart)
+        {
+            _filePart = filePart;
+        }
+
+        public override long Crc
+        {
+            get
+            {
+                if (_filePart == null)
+                {
+                    return 0;
+                }
+                return _filePart.Header.Crc16;
+            }
+        }
+
+        public override string? Key => _filePart?.Header.Name;
+
+        public override string? LinkTarget => null;
+
+        public override long CompressedSize => _filePart?.Header.CompressedSize ?? 0;
+
+        public override CompressionType CompressionType =>
+            _filePart?.Header.CompressionMethod ?? CompressionType.Unknown;
+
+        public override long Size => throw new NotImplementedException();
+
+        public override DateTime? LastModifiedTime => null;
+
+        public override DateTime? CreatedTime => null;
+
+        public override DateTime? LastAccessedTime => null;
+
+        public override DateTime? ArchivedTime => null;
+
+        public override bool IsEncrypted => false;
+
+        public override bool IsDirectory => false;
+
+        public override bool IsSplitAfter => false;
+
+        internal override IEnumerable<FilePart> Parts => _filePart.Empty();
+    }
+}

src/SharpCompress/Common/Arc/ArcEntryHeader.cs

@@ -0,0 +1,76 @@
+using System;
+using System.IO;
+using System.Linq;
+using System.Text;
+
+namespace SharpCompress.Common.Arc
+{
+    public class ArcEntryHeader
+    {
+        public ArchiveEncoding ArchiveEncoding { get; }
+        public CompressionType CompressionMethod { get; private set; }
+        public string? Name { get; private set; }
+        public long CompressedSize { get; private set; }
+        public DateTime DateTime { get; private set; }
+        public int Crc16 { get; private set; }
+        public long OriginalSize { get; private set; }
+        public long DataStartPosition { get; private set; }
+
+        public ArcEntryHeader(ArchiveEncoding archiveEncoding)
+        {
+            this.ArchiveEncoding = archiveEncoding;
+        }
+
+        public ArcEntryHeader? ReadHeader(Stream stream)
+        {
+            byte[] headerBytes = new byte[29];
+            if (stream.Read(headerBytes, 0, headerBytes.Length) != headerBytes.Length)
+            {
+                return null;
+            }
+            DataStartPosition = stream.Position;
+            return LoadFrom(headerBytes);
+        }
+
+        public ArcEntryHeader LoadFrom(byte[] headerBytes)
+        {
+            CompressionMethod = GetCompressionType(headerBytes[1]);
+
+            // Read name
+            int nameEnd = Array.IndexOf(headerBytes, (byte)0, 1); // Find null terminator
+            Name = Encoding.UTF8.GetString(headerBytes, 2, nameEnd > 0 ? nameEnd - 2 : 12);
+
+            int offset = 15;
+            CompressedSize = BitConverter.ToUInt32(headerBytes, offset);
+            offset += 4;
+            uint rawDateTime = BitConverter.ToUInt32(headerBytes, offset);
+            DateTime = ConvertToDateTime(rawDateTime);
+            offset += 4;
+            Crc16 = BitConverter.ToUInt16(headerBytes, offset);
+            offset += 2;
+            OriginalSize = BitConverter.ToUInt32(headerBytes, offset);
+            return this;
+        }
+
+        private CompressionType GetCompressionType(byte value)
+        {
+            return value switch
+            {
+                1 or 2 => CompressionType.None,
+                3 => CompressionType.RLE90,
+                4 => CompressionType.Squeezed,
+                5 or 6 or 7 or 8 => CompressionType.Crunched,
+                9 => CompressionType.Squashed,
+                10 => CompressionType.Crushed,
+                11 => CompressionType.Distilled,
+                _ => CompressionType.Unknown,
+            };
+        }
+
+        public static DateTime ConvertToDateTime(long rawDateTime)
+        {
+            // Convert Unix timestamp to DateTime (UTC)
+            return DateTimeOffset.FromUnixTimeSeconds(rawDateTime).UtcDateTime;
+        }
+    }
+}

src/SharpCompress/Common/Arc/ArcFilePart.cs

@@ -0,0 +1,75 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using SharpCompress.Common.GZip;
+using SharpCompress.Common.Tar;
+using SharpCompress.Common.Tar.Headers;
+using SharpCompress.Common.Zip.Headers;
+using SharpCompress.Compressors.Lzw;
+using SharpCompress.Compressors.RLE90;
+using SharpCompress.Compressors.Squeezed;
+using SharpCompress.IO;
+
+namespace SharpCompress.Common.Arc
+{
+    public class ArcFilePart : FilePart
+    {
+        private readonly Stream? _stream;
+
+        internal ArcFilePart(ArcEntryHeader localArcHeader, Stream? seekableStream)
+            : base(localArcHeader.ArchiveEncoding)
+        {
+            _stream = seekableStream;
+            Header = localArcHeader;
+        }
+
+        internal ArcEntryHeader Header { get; set; }
+
+        internal override string? FilePartName => Header.Name;
+
+        internal override Stream GetCompressedStream()
+        {
+            if (_stream != null)
+            {
+                Stream compressedStream;
+                switch (Header.CompressionMethod)
+                {
+                    case CompressionType.None:
+                        compressedStream = new ReadOnlySubStream(
+                            _stream,
+                            Header.DataStartPosition,
+                            Header.CompressedSize
+                        );
+                        break;
+                    case CompressionType.RLE90:
+                        compressedStream = new RunLength90Stream(
+                            _stream,
+                            (int)Header.CompressedSize
+                        );
+                        break;
+                    case CompressionType.Squeezed:
+                        compressedStream = new SqueezeStream(_stream, (int)Header.CompressedSize);
+                        break;
+                    case CompressionType.Crunched:
+                        compressedStream = new ArcLzwStream(
+                            _stream,
+                            (int)Header.CompressedSize,
+                            true
+                        );
+                        break;
+                    default:
+                        throw new NotSupportedException(
+                            "CompressionMethod: " + Header.CompressionMethod
+                        );
+                }
+                return compressedStream;
+            }
+            return _stream.NotNull();
+        }
+
+        internal override Stream? GetRawStream() => _stream;
+    }
+}

src/SharpCompress/Common/Arc/ArcVolume.cs

@@ -0,0 +1,16 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using SharpCompress.Readers;
+
+namespace SharpCompress.Common.Arc
+{
+    public class ArcVolume : Volume
+    {
+        public ArcVolume(Stream stream, ReaderOptions readerOptions, int index = 0)
+            : base(stream, readerOptions, index) { }
+    }
+}

src/SharpCompress/Common/ArchiveEncoding.cs

@@ -8,12 +8,12 @@ public class ArchiveEncoding
     /// <summary>
     /// Default encoding to use when archive format doesn't specify one.
     /// </summary>
-    public Encoding Default { get; set; }
+    public Encoding? Default { get; set; }
 
     /// <summary>
     /// ArchiveEncoding used by encryption schemes which don't comply with RFC 2898.
     /// </summary>
-    public Encoding Password { get; set; }
+    public Encoding? Password { get; set; }
 
     /// <summary>
     /// Set this encoding when you want to force it for all encoding operations.
@@ -50,6 +50,8 @@ public class ArchiveEncoding
 
     public Encoding GetEncoding() => Forced ?? Default ?? Encoding.UTF8;
 
+    public Encoding GetPasswordEncoding() => Password ?? Encoding.UTF8;
+
     public Func<byte[], int, int, string> GetDecoder() =>
         CustomDecoder ?? ((bytes, index, count) => GetEncoding().GetString(bytes, index, count));
 }

src/SharpCompress/Common/ArchiveException.cs

@@ -1,9 +0,0 @@
-using System;
-
-namespace SharpCompress.Common;
-
-public class ArchiveException : Exception
-{
-    public ArchiveException(string message)
-        : base(message) { }
-}

src/SharpCompress/Common/ArchiveType.cs

@@ -6,5 +6,6 @@ public enum ArchiveType
     Zip,
     Tar,
     SevenZip,
-    GZip
+    GZip,
+    Arc,
 }

src/SharpCompress/Common/CompressionType.cs

@@ -16,5 +16,16 @@ public enum CompressionType
     Unknown,
     Deflate64,
     Shrink,
-    Lzw
+    Lzw,
+    Reduce1,
+    Reduce2,
+    Reduce3,
+    Reduce4,
+    Explode,
+    Squeezed,
+    RLE90,
+    Crunched,
+    Squashed,
+    Crushed,
+    Distilled,
 }

src/SharpCompress/Common/CryptographicException.cs

@@ -1,9 +0,0 @@
-using System;
-
-namespace SharpCompress.Common;
-
-public class CryptographicException : Exception
-{
-    public CryptographicException(string message)
-        : base(message) { }
-}

src/SharpCompress/Common/Entry.cs

@@ -14,7 +14,7 @@ public abstract class Entry : IEntry
     /// <summary>
     /// The string key of the file internal to the Archive.
     /// </summary>
-    public abstract string Key { get; }
+    public abstract string? Key { get; }
 
     /// <summary>
     /// The target of a symlink entry internal to the Archive. Will be null if not a symlink.
@@ -71,11 +71,11 @@ public abstract class Entry : IEntry
     /// </summary>
     public abstract bool IsSplitAfter { get; }
 
-    public int VolumeIndexFirst => Parts?.FirstOrDefault()?.Index ?? 0;
-    public int VolumeIndexLast => Parts?.LastOrDefault()?.Index ?? 0;
+    public int VolumeIndexFirst => Parts.FirstOrDefault()?.Index ?? 0;
+    public int VolumeIndexLast => Parts.LastOrDefault()?.Index ?? 0;
 
     /// <inheritdoc/>
-    public override string ToString() => Key;
+    public override string ToString() => Key ?? "Entry";
 
     internal abstract IEnumerable<FilePart> Parts { get; }
 

src/SharpCompress/Common/ExtractionException.cs

@@ -1,12 +0,0 @@
-using System;
-
-namespace SharpCompress.Common;
-
-public class ExtractionException : Exception
-{
-    public ExtractionException(string message)
-        : base(message) { }
-
-    public ExtractionException(string message, Exception inner)
-        : base(message, inner) { }
-}

src/SharpCompress/Common/ExtractionMethods.cs

@@ -36,10 +36,12 @@ internal static class ExtractionMethods
 
         options ??= new ExtractionOptions() { Overwrite = true };
 
-        var file = Path.GetFileName(entry.Key);
+        var file = Path.GetFileName(entry.Key.NotNull("Entry Key is null")).NotNull("File is null");
+        file = Utility.ReplaceInvalidFileNameChars(file);
         if (options.ExtractFullPath)
         {
-            var folder = Path.GetDirectoryName(entry.Key)!;
+            var folder = Path.GetDirectoryName(entry.Key.NotNull("Entry Key is null"))
+                .NotNull("Directory is null");
             var destdir = Path.GetFullPath(Path.Combine(fullDestinationDirectoryPath, folder));
 
             if (!Directory.Exists(destdir))

src/SharpCompress/Common/FilePart.cs

@@ -8,10 +8,10 @@ public abstract class FilePart
 
     internal ArchiveEncoding ArchiveEncoding { get; }
 
-    internal abstract string FilePartName { get; }
+    internal abstract string? FilePartName { get; }
     public int Index { get; set; }
 
-    internal abstract Stream GetCompressedStream();
+    internal abstract Stream? GetCompressedStream();
     internal abstract Stream? GetRawStream();
     internal bool Skipped { get; set; }
 }

src/SharpCompress/Common/GZip/GZipEntry.cs

@@ -6,23 +6,23 @@ namespace SharpCompress.Common.GZip;
 
 public class GZipEntry : Entry
 {
-    private readonly GZipFilePart _filePart;
+    private readonly GZipFilePart? _filePart;
 
-    internal GZipEntry(GZipFilePart filePart) => _filePart = filePart;
+    internal GZipEntry(GZipFilePart? filePart) => _filePart = filePart;
 
     public override CompressionType CompressionType => CompressionType.GZip;
 
-    public override long Crc => _filePart.Crc ?? 0;
+    public override long Crc => _filePart?.Crc ?? 0;
 
-    public override string Key => _filePart.FilePartName;
+    public override string? Key => _filePart?.FilePartName;
 
     public override string? LinkTarget => null;
 
     public override long CompressedSize => 0;
 
-    public override long Size => _filePart.UncompressedSize ?? 0;
+    public override long Size => _filePart?.UncompressedSize ?? 0;
 
-    public override DateTime? LastModifiedTime => _filePart.DateModified;
+    public override DateTime? LastModifiedTime => _filePart?.DateModified;
 
     public override DateTime? CreatedTime => null;
 
@@ -36,7 +36,7 @@ public class GZipEntry : Entry
 
     public override bool IsSplitAfter => false;
 
-    internal override IEnumerable<FilePart> Parts => _filePart.AsEnumerable<FilePart>();
+    internal override IEnumerable<FilePart> Parts => _filePart.Empty();
 
     internal static IEnumerable<GZipEntry> GetEntries(Stream stream, OptionsBase options)
     {

src/SharpCompress/Common/GZip/GZipFilePart.cs

@@ -34,7 +34,7 @@ internal sealed class GZipFilePart : FilePart
     internal uint? Crc { get; private set; }
     internal uint? UncompressedSize { get; private set; }
 
-    internal override string FilePartName => _name!;
+    internal override string? FilePartName => _name;
 
     internal override Stream GetCompressedStream() =>
         new DeflateStream(_stream, CompressionMode.Decompress, CompressionLevel.Default);

src/SharpCompress/Common/GZip/GZipVolume.cs

@@ -5,7 +5,7 @@ namespace SharpCompress.Common.GZip;
 
 public class GZipVolume : Volume
 {
-    public GZipVolume(Stream stream, ReaderOptions options, int index = 0)
+    public GZipVolume(Stream stream, ReaderOptions? options, int index)
         : base(stream, options, index) { }
 
     public GZipVolume(FileInfo fileInfo, ReaderOptions options)

src/SharpCompress/Common/IEntry.cs

@@ -9,7 +9,7 @@ public interface IEntry
     long CompressedSize { get; }
     long Crc { get; }
     DateTime? CreatedTime { get; }
-    string Key { get; }
+    string? Key { get; }
     string? LinkTarget { get; }
     bool IsDirectory { get; }
     bool IsEncrypted { get; }

src/SharpCompress/Common/IVolume.cs

@@ -6,5 +6,5 @@ public interface IVolume : IDisposable
 {
     int Index { get; }
 
-    string FileName { get; }
+    string? FileName { get; }
 }

src/SharpCompress/Common/IncompleteArchiveException.cs

@@ -1,7 +0,0 @@
-namespace SharpCompress.Common;
-
-public class IncompleteArchiveException : ArchiveException
-{
-    public IncompleteArchiveException(string message)
-        : base(message) { }
-}

src/SharpCompress/Common/InvalidFormatException.cs

@@ -1,12 +0,0 @@
-using System;
-
-namespace SharpCompress.Common;
-
-public class InvalidFormatException : ExtractionException
-{
-    public InvalidFormatException(string message)
-        : base(message) { }
-
-    public InvalidFormatException(string message, Exception inner)
-        : base(message, inner) { }
-}

src/SharpCompress/Common/MultiVolumeExtractionException.cs

@@ -1,12 +0,0 @@
-using System;
-
-namespace SharpCompress.Common;
-
-public class MultiVolumeExtractionException : ExtractionException
-{
-    public MultiVolumeExtractionException(string message)
-        : base(message) { }
-
-    public MultiVolumeExtractionException(string message, Exception inner)
-        : base(message, inner) { }
-}

src/SharpCompress/Common/MultipartStreamRequiredException.cs

@@ -1,7 +0,0 @@
-namespace SharpCompress.Common;
-
-public class MultipartStreamRequiredException : ExtractionException
-{
-    public MultipartStreamRequiredException(string message)
-        : base(message) { }
-}

src/SharpCompress/Common/Rar/CryptKey5.cs

@@ -17,7 +17,7 @@ internal class CryptKey5 : ICryptKey
     private byte[] _pswCheck = { };
     private byte[] _hashKey = { };
 
-    public CryptKey5(string password, Rar5CryptoInfo rar5CryptoInfo)
+    public CryptKey5(string? password, Rar5CryptoInfo rar5CryptoInfo)
     {
         _password = password ?? "";
         _cryptoInfo = rar5CryptoInfo;

src/SharpCompress/Common/Rar/Headers/ArchiveCryptHeader.cs

@@ -1,8 +1,5 @@
 #nullable disable
 
-using System;
-using System.Security.Cryptography;
-using SharpCompress.Common.Rar.Headers;
 using SharpCompress.IO;
 
 namespace SharpCompress.Common.Rar.Headers;

src/SharpCompress/Common/Rar/Headers/FileHeader.cs

@@ -1,9 +1,6 @@
-#nullable disable
-
 using System;
 using System.IO;
 using System.Linq;
-using System.Security.Cryptography;
 using System.Text;
 using SharpCompress.IO;
 #if !Rar2017_64bit
@@ -18,7 +15,7 @@ namespace SharpCompress.Common.Rar.Headers;
 
 internal class FileHeader : RarHeader
 {
-    private byte[] _hash;
+    private byte[]? _hash;
 
     public FileHeader(RarHeader header, RarCrcBinaryReader reader, HeaderType headerType)
         : base(header, reader, headerType) { }
@@ -121,7 +118,6 @@ internal class FileHeader : RarHeader
             switch (type)
             {
                 case FHEXTRA_CRYPT: // file encryption
-
                     {
                         Rar5CryptoInfo = new Rar5CryptoInfo(reader, true);
 
@@ -132,7 +128,6 @@ internal class FileHeader : RarHeader
                     }
                     break;
                 case FHEXTRA_HASH:
-
                     {
                         const uint FHEXTRA_HASH_BLAKE2 = 0x0;
                         //                        const uint HASH_BLAKE2 = 0x03;
@@ -146,7 +141,6 @@ internal class FileHeader : RarHeader
                     }
                     break;
                 case FHEXTRA_HTIME: // file time
-
                     {
                         var flags = reader.ReadRarVIntUInt16();
                         var isWindowsTime = (flags & 1) == 0;
@@ -171,7 +165,6 @@ internal class FileHeader : RarHeader
                 //                        }
                 //                        break;
                 case FHEXTRA_REDIR: // file system redirection
-
                     {
                         RedirType = reader.ReadRarVIntByte();
                         RedirFlags = reader.ReadRarVIntByte();
@@ -284,7 +277,6 @@ internal class FileHeader : RarHeader
         switch (HeaderCode)
         {
             case HeaderCodeV.RAR4_FILE_HEADER:
-
                 {
                     if (HasFlag(FileFlagsV4.UNICODE))
                     {
@@ -311,7 +303,6 @@ internal class FileHeader : RarHeader
                 }
                 break;
             case HeaderCodeV.RAR4_NEW_SUB_HEADER:
-
                 {
                     var datasize = HeaderSize - newLhdSize - nameSize;
                     if (HasFlag(FileFlagsV4.SALT))
@@ -325,6 +316,10 @@ internal class FileHeader : RarHeader
 
                     if (NewSubHeaderType.SUBHEAD_TYPE_RR.Equals(fileNameBytes))
                     {
+                        if (SubData is null)
+                        {
+                            throw new InvalidFormatException();
+                        }
                         RecoverySectors =
                             SubData[8]
                             + (SubData[9] << 8)
@@ -346,12 +341,16 @@ internal class FileHeader : RarHeader
             if (RemainingHeaderBytes(reader) >= 2)
             {
                 var extendedFlags = reader.ReadUInt16();
-                FileLastModifiedTime = ProcessExtendedTimeV4(
-                    extendedFlags,
-                    FileLastModifiedTime,
-                    reader,
-                    0
-                );
+                if (FileLastModifiedTime is not null)
+                {
+                    FileLastModifiedTime = ProcessExtendedTimeV4(
+                        extendedFlags,
+                        FileLastModifiedTime,
+                        reader,
+                        0
+                    );
+                }
+
                 FileCreatedTime = ProcessExtendedTimeV4(extendedFlags, null, reader, 1);
                 FileLastAccessedTime = ProcessExtendedTimeV4(extendedFlags, null, reader, 2);
                 FileArchivedTime = ProcessExtendedTimeV4(extendedFlags, null, reader, 3);
@@ -383,7 +382,7 @@ internal class FileHeader : RarHeader
             var dosTime = reader.ReadUInt32();
             time = Utility.DosDateToDateTime(dosTime);
         }
-        if ((rmode & 4) == 0)
+        if ((rmode & 4) == 0 && time is not null)
         {
             time = time.Value.AddSeconds(1);
         }
@@ -396,7 +395,11 @@ internal class FileHeader : RarHeader
         }
 
         //10^-7 to 10^-3
-        return time.Value.AddMilliseconds(nanosecondHundreds * Math.Pow(10, -4));
+        if (time is not null)
+        {
+            return time.Value.AddMilliseconds(nanosecondHundreds * Math.Pow(10, -4));
+        }
+        return null;
     }
 
     private static string ConvertPathV4(string path)
@@ -412,13 +415,13 @@ internal class FileHeader : RarHeader
         return path;
     }
 
-    public override string ToString() => FileName;
+    public override string ToString() => FileName ?? "FileHeader";
 
     private ushort Flags { get; set; }
 
     private bool HasFlag(ushort flag) => (Flags & flag) == flag;
 
-    internal byte[] FileCrc
+    internal byte[]? FileCrc
     {
         get => _hash;
         private set => _hash = value;
@@ -447,22 +450,22 @@ internal class FileHeader : RarHeader
     public bool IsRedir => RedirType != 0;
     public byte RedirFlags { get; private set; }
     public bool IsRedirDirectory => (RedirFlags & RedirFlagV5.DIRECTORY) != 0;
-    public string RedirTargetName { get; private set; }
+    public string? RedirTargetName { get; private set; }
 
     // unused for UnpackV1 implementation (limitation)
     internal size_t WindowSize { get; private set; }
 
-    internal byte[] R4Salt { get; private set; }
-    internal Rar5CryptoInfo Rar5CryptoInfo { get; private set; }
+    internal byte[]? R4Salt { get; private set; }
+    internal Rar5CryptoInfo? Rar5CryptoInfo { get; private set; }
     private byte HostOs { get; set; }
     internal uint FileAttributes { get; private set; }
     internal long CompressedSize { get; private set; }
     internal long UncompressedSize { get; private set; }
-    internal string FileName { get; private set; }
-    internal byte[] SubData { get; private set; }
+    internal string? FileName { get; private set; }
+    internal byte[]? SubData { get; private set; }
     internal int RecoverySectors { get; private set; }
     internal long DataStartPosition { get; set; }
-    public Stream PackedStream { get; set; }
+    public Stream? PackedStream { get; set; }
 
     public bool IsSplitBefore =>
         IsRar5 ? HasHeaderFlag(HeaderFlagsV5.SPLIT_BEFORE) : HasFlag(FileFlagsV4.SPLIT_BEFORE);

src/SharpCompress/Common/Rar/Headers/Flags.cs

@@ -13,7 +13,7 @@ public enum HeaderType : byte
     Sign,
     NewSub,
     EndArchive,
-    Crypt
+    Crypt,
 }
 
 internal static class HeaderCodeV

src/SharpCompress/Common/Rar/Headers/RarHeader.cs

@@ -1,5 +1,4 @@
 using System;
-using System.IO;
 using SharpCompress.IO;
 
 namespace SharpCompress.Common.Rar.Headers;
@@ -21,7 +20,7 @@ internal class RarHeader : IRarHeader
         {
             return new RarHeader(reader, isRar5, archiveEncoding);
         }
-        catch (EndOfStreamException)
+        catch (InvalidFormatException)
         {
             return null;
         }

src/SharpCompress/Common/Rar/Headers/RarHeaderFactory.cs

@@ -1,7 +1,5 @@
 using System.Collections.Generic;
 using System.IO;
-using System.Linq;
-using SharpCompress.Common.Rar;
 using SharpCompress.IO;
 using SharpCompress.Readers;
 
@@ -98,13 +96,11 @@ public class RarHeaderFactory
                 switch (StreamingMode)
                 {
                     case StreamingMode.Seekable:
-
                         {
                             reader.BaseStream.Position += ph.DataSize;
                         }
                         break;
                     case StreamingMode.Streaming:
-
                         {
                             reader.BaseStream.Skip(ph.DataSize);
                         }
@@ -146,14 +142,12 @@ public class RarHeaderFactory
                 switch (StreamingMode)
                 {
                     case StreamingMode.Seekable:
-
                         {
                             fh.DataStartPosition = reader.BaseStream.Position;
                             reader.BaseStream.Position += fh.CompressedSize;
                         }
                         break;
                     case StreamingMode.Streaming:
-
                         {
                             var ms = new ReadOnlySubStream(reader.BaseStream, fh.CompressedSize);
                             if (fh.R4Salt is null && fh.Rar5CryptoInfo is null)
@@ -164,10 +158,15 @@ public class RarHeaderFactory
                             {
                                 fh.PackedStream = new RarCryptoWrapper(
                                     ms,
-                                    fh.R4Salt is null ? fh.Rar5CryptoInfo.Salt : fh.R4Salt,
                                     fh.R4Salt is null
-                                        ? new CryptKey5(Options.Password!, fh.Rar5CryptoInfo)
-                                        : new CryptKey3(Options.Password!)
+                                        ? fh.Rar5CryptoInfo.NotNull().Salt
+                                        : fh.R4Salt,
+                                    fh.R4Salt is null
+                                        ? new CryptKey5(
+                                            Options.Password,
+                                            fh.Rar5CryptoInfo.NotNull()
+                                        )
+                                        : new CryptKey3(Options.Password)
                                 );
                             }
                         }
@@ -204,14 +203,12 @@ public class RarHeaderFactory
         switch (StreamingMode)
         {
             case StreamingMode.Seekable:
-
                 {
                     fh.DataStartPosition = reader.BaseStream.Position;
                     reader.BaseStream.Position += fh.CompressedSize;
                 }
                 break;
             case StreamingMode.Streaming:
-
                 {
                     //skip the data because it's useless?
                     reader.BaseStream.Skip(fh.CompressedSize);

src/SharpCompress/Common/Rar/RarCryptoWrapper.cs

@@ -70,11 +70,11 @@ internal sealed class RarCryptoWrapper : Stream
 
     protected override void Dispose(bool disposing)
     {
-        if (_rijndael != null)
+        if (disposing)
         {
             _rijndael.Dispose();
-            _rijndael = null!;
         }
+
         base.Dispose(disposing);
     }
 }

src/SharpCompress/Common/Rar/RarEntry.cs

@@ -20,12 +20,12 @@ public abstract class RarEntry : Entry
     /// <summary>
     /// The File's 32 bit CRC Hash
     /// </summary>
-    public override long Crc => BitConverter.ToUInt32(FileHeader.FileCrc, 0);
+    public override long Crc => BitConverter.ToUInt32(FileHeader.FileCrc.NotNull(), 0);
 
     /// <summary>
     /// The path of the file internal to the Rar Archive.
     /// </summary>
-    public override string Key => FileHeader.FileName;
+    public override string? Key => FileHeader.FileName;
 
     public override string? LinkTarget => null;
 
@@ -68,7 +68,7 @@ public abstract class RarEntry : Entry
 
     public bool IsRedir => FileHeader.IsRedir;
 
-    public string RedirTargetName => FileHeader.RedirTargetName;
+    public string? RedirTargetName => FileHeader.RedirTargetName;
 
     public override string ToString() =>
         string.Format(

src/SharpCompress/Common/Rar/RarVolume.cs

@@ -15,17 +15,14 @@ namespace SharpCompress.Common.Rar;
 public abstract class RarVolume : Volume
 {
     private readonly RarHeaderFactory _headerFactory;
-    internal int _maxCompressionAlgorithm;
+    private int _maxCompressionAlgorithm;
 
-    internal RarVolume(StreamingMode mode, Stream stream, ReaderOptions options, int index = 0)
+    internal RarVolume(StreamingMode mode, Stream stream, ReaderOptions options, int index)
         : base(stream, options, index) => _headerFactory = new RarHeaderFactory(mode, options);
 
-#nullable disable
-    internal ArchiveHeader ArchiveHeader { get; private set; }
+    private ArchiveHeader? ArchiveHeader { get; set; }
 
-#nullable enable
-
-    internal StreamingMode Mode => _headerFactory.StreamingMode;
+    private StreamingMode Mode => _headerFactory.StreamingMode;
 
     internal abstract IEnumerable<RarFilePart> ReadFileParts();
 
@@ -39,19 +36,16 @@ public abstract class RarVolume : Volume
             switch (header.HeaderType)
             {
                 case HeaderType.Mark:
-
                     {
                         lastMarkHeader = (MarkHeader)header;
                     }
                     break;
                 case HeaderType.Archive:
-
                     {
                         ArchiveHeader = (ArchiveHeader)header;
                     }
                     break;
                 case HeaderType.File:
-
                     {
                         var fh = (FileHeader)header;
                         if (_maxCompressionAlgorithm < fh.CompressionAlgorithm)
@@ -63,14 +57,12 @@ public abstract class RarVolume : Volume
                     }
                     break;
                 case HeaderType.Service:
-
                     {
                         var fh = (FileHeader)header;
                         if (fh.FileName == "CMT")
                         {
-                            var part = CreateFilePart(lastMarkHeader!, fh);
                             var buffer = new byte[fh.CompressedSize];
-                            part.GetCompressedStream().Read(buffer, 0, buffer.Length);
+                            fh.PackedStream.NotNull().ReadFully(buffer);
                             Comment = Encoding.UTF8.GetString(buffer, 0, buffer.Length - 1);
                         }
                     }
@@ -105,7 +97,7 @@ public abstract class RarVolume : Volume
         get
         {
             EnsureArchiveHeaderLoaded();
-            return ArchiveHeader.IsFirstVolume;
+            return ArchiveHeader?.IsFirstVolume ?? false;
         }
     }
 
@@ -117,7 +109,7 @@ public abstract class RarVolume : Volume
         get
         {
             EnsureArchiveHeaderLoaded();
-            return ArchiveHeader.IsVolume;
+            return ArchiveHeader?.IsVolume ?? false;
         }
     }
 
@@ -130,7 +122,7 @@ public abstract class RarVolume : Volume
         get
         {
             EnsureArchiveHeaderLoaded();
-            return ArchiveHeader.IsSolid;
+            return ArchiveHeader?.IsSolid ?? false;
         }
     }
 

src/SharpCompress/Common/ReaderCancelledException.cs

@@ -1,12 +0,0 @@
-using System;
-
-namespace SharpCompress.Common;
-
-public class ReaderCancelledException : Exception
-{
-    public ReaderCancelledException(string message)
-        : base(message) { }
-
-    public ReaderCancelledException(string message, Exception inner)
-        : base(message, inner) { }
-}

src/SharpCompress/Common/SevenZip/ArchiveDatabase.cs

@@ -35,7 +35,7 @@ internal class ArchiveDatabase
         _packSizes.Clear();
         _packCrCs.Clear();
         _folders.Clear();
-        _numUnpackStreamsVector = null!;
+        _numUnpackStreamsVector = null;
         _files.Clear();
 
         _packStreamStartPositions.Clear();

src/SharpCompress/Common/SevenZip/ArchiveReader.cs

@@ -784,7 +784,7 @@ internal class ArchiveReader
                         );
                         break;
                     default:
-                        throw new InvalidOperationException();
+                        throw new InvalidFormatException();
                 }
             }
         }
@@ -843,7 +843,7 @@ internal class ArchiveReader
                 outStream.ReadExact(data, 0, data.Length);
                 if (outStream.ReadByte() >= 0)
                 {
-                    throw new InvalidOperationException("Decoded stream is longer than expected.");
+                    throw new InvalidFormatException("Decoded stream is longer than expected.");
                 }
                 dataVector.Add(data);
 
@@ -854,7 +854,7 @@ internal class ArchiveReader
                         != folder._unpackCrc
                     )
                     {
-                        throw new InvalidOperationException(
+                        throw new InvalidFormatException(
                             "Decoded stream does not match expected CRC."
                         );
                     }
@@ -996,6 +996,11 @@ internal class ArchiveReader
                             numFiles,
                             delegate(int i, uint? attr)
                             {
+                                // Keep the original attribute value because it could potentially get
+                                // modified in the logic that follows. Some callers of the library may
+                                // find the original value useful.
+                                db._files[i].ExtendedAttrib = attr;
+
                                 // Some third party implementations established an unofficial extension
                                 // of the 7z archive format by placing posix file attributes in the high
                                 // bits of the windows file attributes. This makes use of the fact that
@@ -1220,23 +1225,46 @@ internal class ArchiveReader
 
     #region Public Methods
 
-    public void Open(Stream stream)
+    public void Open(Stream stream, bool lookForHeader)
     {
         Close();
 
         _streamOrigin = stream.Position;
         _streamEnding = stream.Length;
 
-        // TODO: Check Signature!
-        _header = new byte[0x20];
-        for (var offset = 0; offset < 0x20; )
+        var canScan = lookForHeader ? 0x80000 - 20 : 0;
+        while (true)
         {
-            var delta = stream.Read(_header, offset, 0x20 - offset);
-            if (delta == 0)
+            // TODO: Check Signature!
+            _header = new byte[0x20];
+            for (var offset = 0; offset < 0x20; )
             {
-                throw new EndOfStreamException();
+                var delta = stream.Read(_header, offset, 0x20 - offset);
+                if (delta == 0)
+                {
+                    throw new EndOfStreamException();
+                }
+
+                offset += delta;
             }
-            offset += delta;
+
+            if (
+                !lookForHeader
+                || _header
+                    .AsSpan(0, length: 6)
+                    .SequenceEqual<byte>([0x37, 0x7A, 0xBC, 0xAF, 0x27, 0x1C])
+            )
+            {
+                break;
+            }
+
+            if (canScan == 0)
+            {
+                throw new InvalidFormatException("Unable to find 7z signature");
+            }
+
+            canScan--;
+            stream.Position = ++_streamOrigin;
         }
 
         _stream = stream;
@@ -1435,7 +1463,7 @@ internal class ArchiveReader
 #if DEBUG
             Log.WriteLine(_db._files[index].Name);
 #endif
-            if (_db._files[index].CrcDefined)
+            if (_db._files[index].Crc.HasValue)
             {
                 _stream = new CrcCheckStream(_db._files[index].Crc.Value);
             }

src/SharpCompress/Common/SevenZip/CFileItem.cs

@@ -8,18 +8,13 @@ internal class CFileItem
 {
     public long Size { get; internal set; }
     public uint? Attrib { get; internal set; }
+    public uint? ExtendedAttrib { get; internal set; }
     public uint? Crc { get; internal set; }
     public string Name { get; internal set; }
 
     public bool HasStream { get; internal set; }
     public bool IsDir { get; internal set; }
 
-    public bool CrcDefined => Crc != null;
-
-    public bool AttribDefined => Attrib != null;
-
-    public void SetAttrib(uint attrib) => Attrib = attrib;
-
     public DateTime? CTime { get; internal set; }
     public DateTime? ATime { get; internal set; }
     public DateTime? MTime { get; internal set; }

src/SharpCompress/Common/SevenZip/SevenZipEntry.cs

@@ -13,7 +13,7 @@ public class SevenZipEntry : Entry
 
     public override long Crc => FilePart.Header.Crc ?? 0;
 
-    public override string Key => FilePart.Header.Name;
+    public override string? Key => FilePart.Header.Name;
 
     public override string? LinkTarget => null;
 
@@ -38,5 +38,8 @@ public class SevenZipEntry : Entry
     public override int? Attrib =>
         FilePart.Header.Attrib.HasValue ? (int?)FilePart.Header.Attrib.Value : null;
 
+    public int? ExtendedAttrib =>
+        FilePart.Header.ExtendedAttrib.HasValue ? (int?)FilePart.Header.ExtendedAttrib.Value : null;
+
     internal override IEnumerable<FilePart> Parts => FilePart.AsEnumerable<FilePart>();
 }

src/SharpCompress/Common/SevenZip/SevenZipFilePart.cs

@@ -1,4 +1,3 @@
-using System;
 using System.IO;
 using System.Linq;
 using SharpCompress.IO;
@@ -41,7 +40,7 @@ internal class SevenZipFilePart : FilePart
     {
         if (!Header.HasStream)
         {
-            return null!;
+            return Stream.Null;
         }
         var folderStream = _database.GetFolderStream(_stream, Folder!, _database.PasswordProvider);
 
@@ -73,34 +72,24 @@ internal class SevenZipFilePart : FilePart
     private const uint K_PPMD = 0x030401;
     private const uint K_B_ZIP2 = 0x040202;
 
-    internal CompressionType GetCompression()
+    private CompressionType GetCompression()
     {
         if (Header.IsDir)
-            return CompressionType.None;
-
-        var coder = Folder!._coders.First();
-        switch (coder._methodId._id)
         {
-            case K_LZMA:
-            case K_LZMA2:
-            {
-                return CompressionType.LZMA;
-            }
-            case K_PPMD:
-            {
-                return CompressionType.PPMd;
-            }
-            case K_B_ZIP2:
-            {
-                return CompressionType.BZip2;
-            }
-            default:
-                throw new NotImplementedException();
+            return CompressionType.None;
         }
+
+        var coder = Folder.NotNull()._coders.First();
+        return coder._methodId._id switch
+        {
+            K_LZMA or K_LZMA2 => CompressionType.LZMA,
+            K_PPMD => CompressionType.PPMd,
+            K_B_ZIP2 => CompressionType.BZip2,
+            _ => throw new InvalidFormatException(),
+        };
     }
 
     internal bool IsEncrypted =>
-        Header.IsDir
-            ? false
-            : Folder!._coders.FindIndex(c => c._methodId._id == CMethodId.K_AES_ID) != -1;
+        !Header.IsDir
+        && Folder?._coders.FindIndex(c => c._methodId._id == CMethodId.K_AES_ID) != -1;
 }

src/SharpCompress/Common/SharpCompressException.cs

@@ -0,0 +1,48 @@
+using System;
+
+namespace SharpCompress.Common;
+
+public class SharpCompressException : Exception
+{
+    public SharpCompressException() { }
+
+    public SharpCompressException(string message)
+        : base(message) { }
+
+    public SharpCompressException(string message, Exception inner)
+        : base(message, inner) { }
+}
+
+public class ArchiveException(string message) : SharpCompressException(message);
+
+public class IncompleteArchiveException(string message) : ArchiveException(message);
+
+public class CryptographicException(string message) : SharpCompressException(message);
+
+public class ReaderCancelledException(string message) : SharpCompressException(message);
+
+public class ExtractionException : SharpCompressException
+{
+    public ExtractionException() { }
+
+    public ExtractionException(string message)
+        : base(message) { }
+
+    public ExtractionException(string message, Exception inner)
+        : base(message, inner) { }
+}
+
+public class MultipartStreamRequiredException(string message) : ExtractionException(message);
+
+public class MultiVolumeExtractionException(string message) : ExtractionException(message);
+
+public class InvalidFormatException : ExtractionException
+{
+    public InvalidFormatException() { }
+
+    public InvalidFormatException(string message)
+        : base(message) { }
+
+    public InvalidFormatException(string message, Exception inner)
+        : base(message, inner) { }
+}

src/SharpCompress/Common/Tar/Headers/EntryType.cs

@@ -14,5 +14,5 @@ internal enum EntryType : byte
     LongName = (byte)'L',
     SparseFile = (byte)'S',
     VolumeHeader = (byte)'V',
-    GlobalExtendedHeader = (byte)'g'
+    GlobalExtendedHeader = (byte)'g',
 }

src/SharpCompress/Common/Tar/Headers/TarHeader.cs

@@ -1,5 +1,3 @@
-#nullable disable
-
 using System;
 using System.Buffers.Binary;
 using System.IO;
@@ -13,8 +11,8 @@ internal sealed class TarHeader
 
     public TarHeader(ArchiveEncoding archiveEncoding) => ArchiveEncoding = archiveEncoding;
 
-    internal string Name { get; set; }
-    internal string LinkName { get; set; }
+    internal string? Name { get; set; }
+    internal string? LinkName { get; set; }
 
     internal long Mode { get; set; }
     internal long UserId { get; set; }
@@ -22,7 +20,7 @@ internal sealed class TarHeader
     internal long Size { get; set; }
     internal DateTime LastModifiedTime { get; set; }
     internal EntryType EntryType { get; set; }
-    internal Stream PackedStream { get; set; }
+    internal Stream? PackedStream { get; set; }
     internal ArchiveEncoding ArchiveEncoding { get; }
 
     internal const int BLOCK_SIZE = 512;
@@ -36,7 +34,9 @@ internal sealed class TarHeader
         WriteOctalBytes(0, buffer, 116, 8); // group ID
 
         //ArchiveEncoding.UTF8.GetBytes("magic").CopyTo(buffer, 257);
-        var nameByteCount = ArchiveEncoding.GetEncoding().GetByteCount(Name);
+        var nameByteCount = ArchiveEncoding
+            .GetEncoding()
+            .GetByteCount(Name.NotNull("Name is null"));
         if (nameByteCount > 100)
         {
             // Set mock filename and filetype to indicate the next block is the actual name of the file
@@ -46,7 +46,7 @@ internal sealed class TarHeader
         }
         else
         {
-            WriteStringBytes(ArchiveEncoding.Encode(Name), buffer, 100);
+            WriteStringBytes(ArchiveEncoding.Encode(Name.NotNull("Name is null")), buffer, 100);
             WriteOctalBytes(Size, buffer, 124, 12);
             var time = (long)(LastModifiedTime.ToUniversalTime() - EPOCH).TotalSeconds;
             WriteOctalBytes(time, buffer, 136, 12);
@@ -77,7 +77,7 @@ internal sealed class TarHeader
             //
             // and then infinite recursion is occured in WriteLongFilenameHeader because truncated.Length is 102.
             Name = ArchiveEncoding.Decode(
-                ArchiveEncoding.Encode(Name),
+                ArchiveEncoding.Encode(Name.NotNull("Name is null")),
                 0,
                 100 - ArchiveEncoding.GetEncoding().GetMaxByteCount(1)
             );
@@ -87,7 +87,7 @@ internal sealed class TarHeader
 
     private void WriteLongFilenameHeader(Stream output)
     {
-        var nameBytes = ArchiveEncoding.Encode(Name);
+        var nameBytes = ArchiveEncoding.Encode(Name.NotNull("Name is null"));
         output.Write(nameBytes, 0, nameBytes.Length);
 
         // pad to multiple of BlockSize bytes, and make sure a terminating null is added
@@ -101,57 +101,85 @@ internal sealed class TarHeader
 
     internal bool Read(BinaryReader reader)
     {
-        var buffer = ReadBlock(reader);
-        if (buffer.Length == 0)
+        string? longName = null;
+        string? longLinkName = null;
+        var hasLongValue = true;
+        byte[] buffer;
+        EntryType entryType;
+
+        do
+        {
+            buffer = ReadBlock(reader);
+
+            if (buffer.Length == 0)
+            {
+                return false;
+            }
+
+            entryType = ReadEntryType(buffer);
+
+            // LongName and LongLink headers can follow each other and need
+            // to apply to the header that follows them.
+            if (entryType == EntryType.LongName)
+            {
+                longName = ReadLongName(reader, buffer);
+                continue;
+            }
+            else if (entryType == EntryType.LongLink)
+            {
+                longLinkName = ReadLongName(reader, buffer);
+                continue;
+            }
+
+            hasLongValue = false;
+        } while (hasLongValue);
+
+        // Check header checksum
+        if (!checkChecksum(buffer))
         {
             return false;
         }
 
-        // for symlinks, additionally read the linkname
-        if (ReadEntryType(buffer) == EntryType.SymLink)
-        {
-            LinkName = ArchiveEncoding.Decode(buffer, 157, 100).TrimNulls();
-        }
-
-        if (ReadEntryType(buffer) == EntryType.LongName)
-        {
-            Name = ReadLongName(reader, buffer);
-            buffer = ReadBlock(reader);
-        }
-        else
-        {
-            Name = ArchiveEncoding.Decode(buffer, 0, 100).TrimNulls();
-        }
-
-        EntryType = ReadEntryType(buffer);
+        Name = longName ?? ArchiveEncoding.Decode(buffer, 0, 100).TrimNulls();
+        EntryType = entryType;
         Size = ReadSize(buffer);
 
+        // for symlinks, additionally read the linkname
+        if (entryType == EntryType.SymLink || entryType == EntryType.HardLink)
+        {
+            LinkName = longLinkName ?? ArchiveEncoding.Decode(buffer, 157, 100).TrimNulls();
+        }
+
         Mode = ReadAsciiInt64Base8(buffer, 100, 7);
-        if (EntryType == EntryType.Directory)
+
+        if (entryType == EntryType.Directory)
         {
             Mode |= 0b1_000_000_000;
         }
 
         UserId = ReadAsciiInt64Base8oldGnu(buffer, 108, 7);
         GroupId = ReadAsciiInt64Base8oldGnu(buffer, 116, 7);
-        var unixTimeStamp = ReadAsciiInt64Base8(buffer, 136, 11);
-        LastModifiedTime = EPOCH.AddSeconds(unixTimeStamp).ToLocalTime();
 
+        var unixTimeStamp = ReadAsciiInt64Base8(buffer, 136, 11);
+
+        LastModifiedTime = EPOCH.AddSeconds(unixTimeStamp).ToLocalTime();
         Magic = ArchiveEncoding.Decode(buffer, 257, 6).TrimNulls();
 
         if (!string.IsNullOrEmpty(Magic) && "ustar".Equals(Magic))
         {
-            var namePrefix = ArchiveEncoding.Decode(buffer, 345, 157);
-            namePrefix = namePrefix.TrimNulls();
+            var namePrefix = ArchiveEncoding.Decode(buffer, 345, 157).TrimNulls();
+
             if (!string.IsNullOrEmpty(namePrefix))
             {
                 Name = namePrefix + "/" + Name;
             }
         }
-        if (EntryType != EntryType.LongName && Name.Length == 0)
+
+        if (entryType != EntryType.LongName && Name.Length == 0)
         {
             return false;
         }
+
         return true;
     }
 
@@ -188,7 +216,7 @@ internal sealed class TarHeader
 
         if (buffer.Length != 0 && buffer.Length < BLOCK_SIZE)
         {
-            throw new InvalidOperationException("Buffer is invalid size");
+            throw new InvalidFormatException("Buffer is invalid size");
         }
         return buffer;
     }
@@ -286,9 +314,45 @@ internal sealed class TarHeader
         (byte)' ',
         (byte)' ',
         (byte)' ',
-        (byte)' '
+        (byte)' ',
     };
 
+    internal static bool checkChecksum(byte[] buf)
+    {
+        const int eightSpacesChksum = 256;
+        var buffer = new Span<byte>(buf).Slice(0, 512);
+        int posix_sum = eightSpacesChksum;
+        int sun_sum = eightSpacesChksum;
+
+        foreach (byte b in buffer)
+        {
+            posix_sum += b;
+            sun_sum += unchecked((sbyte)b);
+        }
+
+        // Special case, empty file header
+        if (posix_sum == eightSpacesChksum)
+        {
+            return true;
+        }
+
+        // Remove current checksum from calculation
+        foreach (byte b in buffer.Slice(148, 8))
+        {
+            posix_sum -= b;
+            sun_sum -= unchecked((sbyte)b);
+        }
+
+        // Read and compare checksum for header
+        var crc = ReadAsciiInt64Base8(buf, 148, 7);
+        if (crc != posix_sum && crc != sun_sum)
+        {
+            return false;
+        }
+
+        return true;
+    }
+
     internal static int RecalculateChecksum(byte[] buf)
     {
         // Set default value for checksum. That is 8 spaces.
@@ -323,5 +387,5 @@ internal sealed class TarHeader
 
     public long? DataStartPosition { get; set; }
 
-    public string Magic { get; set; }
+    public string? Magic { get; set; }
 }

src/SharpCompress/Common/Tar/TarEntry.cs

@@ -1,5 +1,3 @@
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using System.IO;
@@ -10,9 +8,9 @@ namespace SharpCompress.Common.Tar;
 
 public class TarEntry : Entry
 {
-    private readonly TarFilePart _filePart;
+    private readonly TarFilePart? _filePart;
 
-    internal TarEntry(TarFilePart filePart, CompressionType type)
+    internal TarEntry(TarFilePart? filePart, CompressionType type)
     {
         _filePart = filePart;
         CompressionType = type;
@@ -22,15 +20,15 @@ public class TarEntry : Entry
 
     public override long Crc => 0;
 
-    public override string Key => _filePart.Header.Name;
+    public override string? Key => _filePart?.Header.Name;
 
-    public override string LinkTarget => _filePart.Header.LinkName;
+    public override string? LinkTarget => _filePart?.Header.LinkName;
 
-    public override long CompressedSize => _filePart.Header.Size;
+    public override long CompressedSize => _filePart?.Header.Size ?? 0;
 
-    public override long Size => _filePart.Header.Size;
+    public override long Size => _filePart?.Header.Size ?? 0;
 
-    public override DateTime? LastModifiedTime => _filePart.Header.LastModifiedTime;
+    public override DateTime? LastModifiedTime => _filePart?.Header.LastModifiedTime;
 
     public override DateTime? CreatedTime => null;
 
@@ -40,17 +38,17 @@ public class TarEntry : Entry
 
     public override bool IsEncrypted => false;
 
-    public override bool IsDirectory => _filePart.Header.EntryType == EntryType.Directory;
+    public override bool IsDirectory => _filePart?.Header.EntryType == EntryType.Directory;
 
     public override bool IsSplitAfter => false;
 
-    public long Mode => _filePart.Header.Mode;
+    public long Mode => _filePart?.Header.Mode ?? 0;
 
-    public long UserID => _filePart.Header.UserId;
+    public long UserID => _filePart?.Header.UserId ?? 0;
 
-    public long GroupId => _filePart.Header.GroupId;
+    public long GroupId => _filePart?.Header.GroupId ?? 0;
 
-    internal override IEnumerable<FilePart> Parts => _filePart.AsEnumerable<FilePart>();
+    internal override IEnumerable<FilePart> Parts => _filePart.Empty();
 
     internal static IEnumerable<TarEntry> GetEntries(
         StreamingMode mode,
@@ -59,17 +57,17 @@ public class TarEntry : Entry
         ArchiveEncoding archiveEncoding
     )
     {
-        foreach (var h in TarHeaderFactory.ReadHeader(mode, stream, archiveEncoding))
+        foreach (var header in TarHeaderFactory.ReadHeader(mode, stream, archiveEncoding))
         {
-            if (h != null)
+            if (header != null)
             {
                 if (mode == StreamingMode.Seekable)
                 {
-                    yield return new TarEntry(new TarFilePart(h, stream), compressionType);
+                    yield return new TarEntry(new TarFilePart(header, stream), compressionType);
                 }
                 else
                 {
-                    yield return new TarEntry(new TarFilePart(h, null), compressionType);
+                    yield return new TarEntry(new TarFilePart(header, null), compressionType);
                 }
             }
             else

src/SharpCompress/Common/Tar/TarFilePart.cs

@@ -5,9 +5,9 @@ namespace SharpCompress.Common.Tar;
 
 internal sealed class TarFilePart : FilePart
 {
-    private readonly Stream _seekableStream;
+    private readonly Stream? _seekableStream;
 
-    internal TarFilePart(TarHeader header, Stream seekableStream)
+    internal TarFilePart(TarHeader header, Stream? seekableStream)
         : base(header.ArchiveEncoding)
     {
         _seekableStream = seekableStream;
@@ -16,16 +16,16 @@ internal sealed class TarFilePart : FilePart
 
     internal TarHeader Header { get; }
 
-    internal override string FilePartName => Header.Name;
+    internal override string? FilePartName => Header?.Name;
 
     internal override Stream GetCompressedStream()
     {
         if (_seekableStream != null)
         {
-            _seekableStream.Position = Header.DataStartPosition!.Value;
+            _seekableStream.Position = Header.DataStartPosition ?? 0;
             return new TarReadOnlySubStream(_seekableStream, Header.Size);
         }
-        return Header.PackedStream;
+        return Header.PackedStream.NotNull();
     }
 
     internal override Stream? GetRawStream() => null;

src/SharpCompress/Common/Tar/TarHeaderFactory.cs

@@ -28,7 +28,6 @@ internal static class TarHeaderFactory
                 switch (mode)
                 {
                     case StreamingMode.Seekable:
-
                         {
                             header.DataStartPosition = reader.BaseStream.Position;
 
@@ -37,7 +36,6 @@ internal static class TarHeaderFactory
                         }
                         break;
                     case StreamingMode.Streaming:
-
                         {
                             header.PackedStream = new TarReadOnlySubStream(stream, header.Size);
                         }

src/SharpCompress/Common/Volume.cs

@@ -9,11 +9,11 @@ public abstract class Volume : IVolume
 {
     private readonly Stream _actualStream;
 
-    internal Volume(Stream stream, ReaderOptions readerOptions, int index = 0)
+    internal Volume(Stream stream, ReaderOptions? readerOptions, int index = 0)
     {
         Index = index;
-        ReaderOptions = readerOptions;
-        if (readerOptions.LeaveStreamOpen)
+        ReaderOptions = readerOptions ?? new ReaderOptions();
+        if (ReaderOptions.LeaveStreamOpen)
         {
             stream = NonDisposingStream.Create(stream);
         }
@@ -32,7 +32,7 @@ public abstract class Volume : IVolume
 
     public virtual int Index { get; internal set; }
 
-    public string FileName => (_actualStream as FileStream)?.Name!;
+    public string? FileName => (_actualStream as FileStream)?.Name;
 
     /// <summary>
     /// RarArchive is part of a multi-part archive.

src/SharpCompress/Common/Zip/Headers/HeaderFlags.cs

@@ -13,5 +13,5 @@ internal enum HeaderFlags : ushort
     EnhancedDeflate = 16,
 
     //Bit 11: Language encoding flag
-    Efs = 2048
+    Efs = 2048,
 }

src/SharpCompress/Common/Zip/Headers/LocalEntryHeaderExtraFactory.cs

@@ -14,7 +14,7 @@ internal enum ExtraDataType : ushort
     // -Info-ZIP Unicode Path Extra Field
     UnicodePathExtraField = 0x7075,
     Zip64ExtendedInformationExtraField = 0x0001,
-    UnixTimeExtraField = 0x5455
+    UnixTimeExtraField = 0x5455,
 }
 
 internal class ExtraData
@@ -166,10 +166,10 @@ internal sealed class UnixTimeExtraField : ExtraData
                 return Tuple.Create<DateTime?, DateTime?, DateTime?>(null, null, null);
             }
 
-            var flags = DataBytes[0];
-            var isModifiedTimeSpecified = (flags & 0x01) == 1;
-            var isLastAccessTimeSpecified = (flags & 0x02) == 1;
-            var isCreationTimeSpecified = (flags & 0x04) == 1;
+            var flags = (RecordedTimeFlag)DataBytes[0];
+            var isModifiedTimeSpecified = flags.HasFlag(RecordedTimeFlag.LastModified);
+            var isLastAccessTimeSpecified = flags.HasFlag(RecordedTimeFlag.LastAccessed);
+            var isCreationTimeSpecified = flags.HasFlag(RecordedTimeFlag.Created);
             var currentIndex = 1;
             DateTime? modifiedTime = null;
             DateTime? lastAccessTime = null;
@@ -189,7 +189,7 @@ internal sealed class UnixTimeExtraField : ExtraData
             {
                 if (currentIndex + 4 > DataBytes.Length)
                 {
-                    throw new ArchiveException("Invalid UnicodeExtraTime field");
+                    return Tuple.Create<DateTime?, DateTime?, DateTime?>(null, null, null);
                 }
 
                 var lastAccessEpochTime = BinaryPrimitives.ReadInt32LittleEndian(
@@ -206,7 +206,7 @@ internal sealed class UnixTimeExtraField : ExtraData
             {
                 if (currentIndex + 4 > DataBytes.Length)
                 {
-                    throw new ArchiveException("Invalid UnicodeExtraTime field");
+                    return Tuple.Create<DateTime?, DateTime?, DateTime?>(null, null, null);
                 }
 
                 var creationTimeEpochTime = BinaryPrimitives.ReadInt32LittleEndian(
@@ -222,6 +222,15 @@ internal sealed class UnixTimeExtraField : ExtraData
             return Tuple.Create(modifiedTime, lastAccessTime, creationTime);
         }
     }
+
+    [Flags]
+    private enum RecordedTimeFlag
+    {
+        None = 0,
+        LastModified = 1,
+        LastAccessed = 2,
+        Created = 4,
+    }
 }
 
 internal static class LocalEntryHeaderExtraFactory
@@ -229,11 +238,14 @@ internal static class LocalEntryHeaderExtraFactory
     internal static ExtraData Create(ExtraDataType type, ushort length, byte[] extraData) =>
         type switch
         {
-            ExtraDataType.UnicodePathExtraField
-                => new ExtraUnicodePathExtraField(type, length, extraData),
-            ExtraDataType.Zip64ExtendedInformationExtraField
-                => new Zip64ExtendedInformationExtraField(type, length, extraData),
+            ExtraDataType.UnicodePathExtraField => new ExtraUnicodePathExtraField(
+                type,
+                length,
+                extraData
+            ),
+            ExtraDataType.Zip64ExtendedInformationExtraField =>
+                new Zip64ExtendedInformationExtraField(type, length, extraData),
             ExtraDataType.UnixTimeExtraField => new UnixTimeExtraField(type, length, extraData),
-            _ => new ExtraData(type, length, extraData)
+            _ => new ExtraData(type, length, extraData),
         };
 }

src/SharpCompress/Common/Zip/Headers/ZipFileEntry.cs

@@ -1,5 +1,3 @@
-#nullable disable
-
 using System;
 using System.Buffers.Binary;
 using System.Collections.Generic;
@@ -20,21 +18,21 @@ internal abstract class ZipFileEntry : ZipHeader
     {
         get
         {
-            if (Name.EndsWith('/'))
+            if (Name?.EndsWith('/') ?? false)
             {
                 return true;
             }
 
             //.NET Framework 4.5 : System.IO.Compression::CreateFromDirectory() probably writes backslashes to headers
-            return CompressedSize == 0 && UncompressedSize == 0 && Name.EndsWith('\\');
+            return CompressedSize == 0 && UncompressedSize == 0 && (Name?.EndsWith('\\') ?? false);
         }
     }
 
-    internal Stream PackedStream { get; set; }
+    internal Stream? PackedStream { get; set; }
 
     internal ArchiveEncoding ArchiveEncoding { get; }
 
-    internal string Name { get; set; }
+    internal string? Name { get; set; }
 
     internal HeaderFlags Flags { get; set; }
 
@@ -48,7 +46,7 @@ internal abstract class ZipFileEntry : ZipHeader
 
     internal List<ExtraData> Extra { get; set; }
 
-    public string Password { get; set; }
+    public string? Password { get; set; }
 
     internal PkwareTraditionalEncryptionData ComposeEncryptionData(Stream archiveStream)
     {
@@ -65,7 +63,7 @@ internal abstract class ZipFileEntry : ZipHeader
         return encryptionData;
     }
 
-    internal WinzipAesEncryptionData WinzipAesEncryptionData { get; set; }
+    internal WinzipAesEncryptionData? WinzipAesEncryptionData { get; set; }
 
     /// <summary>
     /// The last modified date as read from the Local or Central Directory header.
@@ -119,7 +117,7 @@ internal abstract class ZipFileEntry : ZipHeader
         }
     }
 
-    internal ZipFilePart Part { get; set; }
+    internal ZipFilePart? Part { get; set; }
 
     internal bool IsZip64 => CompressedSize >= uint.MaxValue;
 }

src/SharpCompress/Common/Zip/Headers/ZipHeaderType.cs

@@ -8,5 +8,5 @@ internal enum ZipHeaderType
     DirectoryEnd,
     Split,
     Zip64DirectoryEnd,
-    Zip64DirectoryEndLocator
+    Zip64DirectoryEndLocator,
 }

src/SharpCompress/Common/Zip/PkwareTraditionalCryptoStream.cs

@@ -6,7 +6,7 @@ namespace SharpCompress.Common.Zip;
 internal enum CryptoMode
 {
     Encrypt,
-    Decrypt
+    Decrypt,
 }
 
 internal class PkwareTraditionalCryptoStream : Stream

src/SharpCompress/Common/Zip/PkwareTraditionalEncryptionData.cs

@@ -103,7 +103,7 @@ internal class PkwareTraditionalEncryptionData
 
     internal byte[] StringToByteArray(string value)
     {
-        var a = _archiveEncoding.Password.GetBytes(value);
+        var a = _archiveEncoding.GetPasswordEncoding().GetBytes(value);
         return a;
     }
 

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;
 
@@ -8,18 +7,13 @@ internal class SeekableZipFilePart : ZipFilePart
 {
     private bool _isLocalHeaderLoaded;
     private readonly SeekableZipHeaderFactory _headerFactory;
-    private readonly DirectoryEntryHeader _directoryEntryHeader;
 
     internal SeekableZipFilePart(
         SeekableZipHeaderFactory headerFactory,
         DirectoryEntryHeader header,
         Stream stream
     )
-        : base(header, stream)
-    {
-        _headerFactory = headerFactory;
-        _directoryEntryHeader = header;
-    }
+        : base(header, stream) => _headerFactory = headerFactory;
 
     internal override Stream GetCompressedStream()
     {
@@ -42,17 +36,7 @@ internal class SeekableZipFilePart : ZipFilePart
 
     protected override Stream CreateBaseStream()
     {
-        BaseStream.Position = Header.DataStartPosition!.Value;
-
-        if (
-            (Header.CompressedSize == 0)
-            && FlagUtility.HasFlag(Header.Flags, HeaderFlags.UsePostDataDescriptor)
-            && (_directoryEntryHeader?.HasData == true)
-            && (_directoryEntryHeader?.CompressedSize != 0)
-        )
-        {
-            return new ReadOnlySubStream(BaseStream, _directoryEntryHeader!.CompressedSize);
-        }
+        BaseStream.Position = Header.DataStartPosition.NotNull();
 
         return BaseStream;
     }

src/SharpCompress/Common/Zip/SeekableZipHeaderFactory.cs

@@ -149,6 +149,12 @@ internal sealed class SeekableZipHeaderFactory : ZipHeaderFactory
         {
             throw new InvalidOperationException();
         }
+        if (FlagUtility.HasFlag(localEntryHeader.Flags, HeaderFlags.UsePostDataDescriptor))
+        {
+            localEntryHeader.Crc = directoryEntryHeader.Crc;
+            localEntryHeader.CompressedSize = directoryEntryHeader.CompressedSize;
+            localEntryHeader.UncompressedSize = directoryEntryHeader.UncompressedSize;
+        }
         return localEntryHeader;
     }
 }

src/SharpCompress/Common/Zip/StreamingZipFilePart.cs

@@ -1,5 +1,4 @@
 using System.IO;
-using System.Net.Sockets;
 using SharpCompress.Common.Zip.Headers;
 using SharpCompress.Compressors.Deflate;
 using SharpCompress.IO;
@@ -13,7 +12,7 @@ internal sealed class StreamingZipFilePart : ZipFilePart
     internal StreamingZipFilePart(ZipFileEntry header, Stream stream)
         : base(header, stream) { }
 
-    protected override Stream CreateBaseStream() => Header.PackedStream;
+    protected override Stream CreateBaseStream() => Header.PackedStream.NotNull();
 
     internal override Stream GetCompressedStream()
     {

src/SharpCompress/Common/Zip/StreamingZipHeaderFactory.cs

@@ -36,16 +36,19 @@ internal class StreamingZipHeaderFactory : ZipHeaderFactory
             uint headerBytes = 0;
             if (
                 _lastEntryHeader != null
-                && (
-                    FlagUtility.HasFlag(_lastEntryHeader.Flags, HeaderFlags.UsePostDataDescriptor)
-                    || _lastEntryHeader.IsZip64
-                )
+                && FlagUtility.HasFlag(_lastEntryHeader.Flags, HeaderFlags.UsePostDataDescriptor)
             )
             {
+                if (_lastEntryHeader.Part is null)
+                {
+                    continue;
+                }
                 reader = ((StreamingZipFilePart)_lastEntryHeader.Part).FixStreamedFileLocation(
                     ref rewindableStream
                 );
+
                 var pos = rewindableStream.CanSeek ? (long?)rewindableStream.Position : null;
+
                 var crc = reader.ReadUInt32();
                 if (crc == POST_DATA_DESCRIPTOR)
                 {
@@ -78,6 +81,60 @@ internal class StreamingZipHeaderFactory : ZipHeaderFactory
                     _lastEntryHeader.DataStartPosition = pos - _lastEntryHeader.CompressedSize;
                 }
             }
+            else if (_lastEntryHeader != null && _lastEntryHeader.IsZip64)
+            {
+                if (_lastEntryHeader.Part is null)
+                    continue;
+
+                reader = ((StreamingZipFilePart)_lastEntryHeader.Part).FixStreamedFileLocation(
+                    ref rewindableStream
+                );
+
+                var pos = rewindableStream.CanSeek ? (long?)rewindableStream.Position : null;
+
+                headerBytes = reader.ReadUInt32();
+
+                var version = reader.ReadUInt16();
+                var flags = (HeaderFlags)reader.ReadUInt16();
+                var compressionMethod = (ZipCompressionMethod)reader.ReadUInt16();
+                var lastModifiedDate = reader.ReadUInt16();
+                var lastModifiedTime = reader.ReadUInt16();
+
+                var crc = reader.ReadUInt32();
+
+                if (crc == POST_DATA_DESCRIPTOR)
+                {
+                    crc = reader.ReadUInt32();
+                }
+                _lastEntryHeader.Crc = crc;
+
+                // The DataDescriptor can be either 64bit or 32bit
+                var compressed_size = reader.ReadUInt32();
+                var uncompressed_size = reader.ReadUInt32();
+
+                // Check if we have header or 64bit DataDescriptor
+                var test_header = !(headerBytes == 0x04034b50 || headerBytes == 0x02014b50);
+
+                var test_64bit = ((long)uncompressed_size << 32) | compressed_size;
+                if (test_64bit == _lastEntryHeader.CompressedSize && test_header)
+                {
+                    _lastEntryHeader.UncompressedSize =
+                        ((long)reader.ReadUInt32() << 32) | headerBytes;
+                    headerBytes = reader.ReadUInt32();
+                }
+                else
+                {
+                    _lastEntryHeader.UncompressedSize = uncompressed_size;
+                }
+
+                if (pos.HasValue)
+                {
+                    _lastEntryHeader.DataStartPosition = pos - _lastEntryHeader.CompressedSize;
+
+                    // 4 = First 4 bytes of the entry header (i.e. 50 4B 03 04)
+                    rewindableStream.Position = pos.Value + 4;
+                }
+            }
             else
             {
                 headerBytes = reader.ReadUInt32();

src/SharpCompress/Common/Zip/WinzipAesEncryptionData.cs

@@ -1,5 +1,3 @@
-#nullable disable
-
 using System;
 using System.Buffers.Binary;
 using System.Security.Cryptography;
@@ -10,12 +8,7 @@ internal class WinzipAesEncryptionData
 {
     private const int RFC2898_ITERATIONS = 1000;
 
-    private readonly byte[] _salt;
     private readonly WinzipAesKeySize _keySize;
-    private readonly byte[] _passwordVerifyValue;
-    private readonly string _password;
-
-    private byte[] _generatedVerifyValue;
 
     internal WinzipAesEncryptionData(
         WinzipAesKeySize keySize,
@@ -25,10 +18,28 @@ internal class WinzipAesEncryptionData
     )
     {
         _keySize = keySize;
-        _salt = salt;
-        _passwordVerifyValue = passwordVerifyValue;
-        _password = password;
-        Initialize();
+
+#if NETFRAMEWORK || NETSTANDARD2_0
+        var rfc2898 = new Rfc2898DeriveBytes(password, salt, RFC2898_ITERATIONS);
+#else
+        var rfc2898 = new Rfc2898DeriveBytes(
+            password,
+            salt,
+            RFC2898_ITERATIONS,
+            HashAlgorithmName.SHA1
+        );
+#endif
+
+        KeyBytes = rfc2898.GetBytes(KeySizeInBytes); // 16 or 24 or 32 ???
+        IvBytes = rfc2898.GetBytes(KeySizeInBytes);
+        var generatedVerifyValue = rfc2898.GetBytes(2);
+
+        var verify = BinaryPrimitives.ReadInt16LittleEndian(passwordVerifyValue);
+        var generated = BinaryPrimitives.ReadInt16LittleEndian(generatedVerifyValue);
+        if (verify != generated)
+        {
+            throw new InvalidFormatException("bad password");
+        }
     }
 
     internal byte[] IvBytes { get; set; }
@@ -45,32 +56,4 @@ internal class WinzipAesEncryptionData
             WinzipAesKeySize.KeySize256 => 32,
             _ => throw new InvalidOperationException(),
         };
-
-    private void Initialize()
-    {
-#if NETFRAMEWORK || NETSTANDARD2_0
-        var rfc2898 = new Rfc2898DeriveBytes(_password, _salt, RFC2898_ITERATIONS);
-#else
-        var rfc2898 = new Rfc2898DeriveBytes(
-            _password,
-            _salt,
-            RFC2898_ITERATIONS,
-            HashAlgorithmName.SHA1
-        );
-#endif
-
-        KeyBytes = rfc2898.GetBytes(KeySizeInBytes); // 16 or 24 or 32 ???
-        IvBytes = rfc2898.GetBytes(KeySizeInBytes);
-        _generatedVerifyValue = rfc2898.GetBytes(2);
-
-        var verify = BinaryPrimitives.ReadInt16LittleEndian(_passwordVerifyValue);
-        if (_password != null)
-        {
-            var generated = BinaryPrimitives.ReadInt16LittleEndian(_generatedVerifyValue);
-            if (verify != generated)
-            {
-                throw new InvalidFormatException("bad password");
-            }
-        }
-    }
 }

src/SharpCompress/Common/Zip/WinzipAesKeySize.cs

@@ -4,5 +4,5 @@ internal enum WinzipAesKeySize
 {
     KeySize128 = 1,
     KeySize192 = 2,
-    KeySize256 = 3
+    KeySize256 = 3,
 }

src/SharpCompress/Common/Zip/ZipCompressionMethod.cs

@@ -4,6 +4,11 @@ internal enum ZipCompressionMethod
 {
     None = 0,
     Shrink = 1,
+    Reduce1 = 2,
+    Reduce2 = 3,
+    Reduce3 = 4,
+    Reduce4 = 5,
+    Explode = 6,
     Deflate = 8,
     Deflate64 = 9,
     BZip2 = 12,
@@ -11,5 +16,5 @@ internal enum ZipCompressionMethod
     ZStd = 93,
     Xz = 95,
     PPMd = 98,
-    WinzipAes = 0x63 //http://www.winzip.com/aes_info.htm
+    WinzipAes = 0x63, //http://www.winzip.com/aes_info.htm
 }

src/SharpCompress/Common/Zip/ZipEntry.cs

@@ -1,29 +1,38 @@
-#nullable disable
-
 using System;
 using System.Collections.Generic;
+using System.Linq;
 using SharpCompress.Common.Zip.Headers;
 
 namespace SharpCompress.Common.Zip;
 
 public class ZipEntry : Entry
 {
-    private readonly ZipFilePart _filePart;
+    private readonly ZipFilePart? _filePart;
 
-    internal ZipEntry(ZipFilePart filePart)
+    internal ZipEntry(ZipFilePart? filePart)
     {
-        if (filePart != null)
+        if (filePart == null)
         {
-            _filePart = filePart;
-            LastModifiedTime = Utility.DosDateToDateTime(
-                filePart.Header.LastModifiedDate,
-                filePart.Header.LastModifiedTime
-            );
+            return;
         }
+        _filePart = filePart;
+
+        LastModifiedTime = Utility.DosDateToDateTime(
+            filePart.Header.LastModifiedDate,
+            filePart.Header.LastModifiedTime
+        );
+
+        var times =
+            filePart.Header.Extra.FirstOrDefault(header =>
+                header.GetType() == typeof(UnixTimeExtraField)
+            ) as UnixTimeExtraField;
+
+        LastAccessedTime = times?.UnicodeTimes.Item2;
+        CreatedTime = times?.UnicodeTimes.Item3;
     }
 
     public override CompressionType CompressionType =>
-        _filePart.Header.CompressionMethod switch
+        _filePart?.Header.CompressionMethod switch
         {
             ZipCompressionMethod.BZip2 => CompressionType.BZip2,
             ZipCompressionMethod.Deflate => CompressionType.Deflate,
@@ -32,33 +41,46 @@ public class ZipEntry : Entry
             ZipCompressionMethod.PPMd => CompressionType.PPMd,
             ZipCompressionMethod.None => CompressionType.None,
             ZipCompressionMethod.Shrink => CompressionType.Shrink,
-            _ => CompressionType.Unknown
+            ZipCompressionMethod.Reduce1 => CompressionType.Reduce1,
+            ZipCompressionMethod.Reduce2 => CompressionType.Reduce2,
+            ZipCompressionMethod.Reduce3 => CompressionType.Reduce3,
+            ZipCompressionMethod.Reduce4 => CompressionType.Reduce4,
+            ZipCompressionMethod.Explode => CompressionType.Explode,
+            _ => CompressionType.Unknown,
         };
 
-    public override long Crc => _filePart.Header.Crc;
+    public override long Crc => _filePart?.Header.Crc ?? 0;
 
-    public override string Key => _filePart.Header.Name;
+    public override string? Key => _filePart?.Header.Name;
 
-    public override string LinkTarget => null;
+    public override string? LinkTarget => null;
 
-    public override long CompressedSize => _filePart.Header.CompressedSize;
+    public override long CompressedSize => _filePart?.Header.CompressedSize ?? 0;
 
-    public override long Size => _filePart.Header.UncompressedSize;
+    public override long Size => _filePart?.Header.UncompressedSize ?? 0;
 
     public override DateTime? LastModifiedTime { get; }
 
-    public override DateTime? CreatedTime => null;
+    /// <inheritdoc/>
+    /// <remarks>
+    /// The returned time is UTC, not local.
+    /// </remarks>
+    public override DateTime? CreatedTime { get; }
 
-    public override DateTime? LastAccessedTime => null;
+    /// <inheritdoc/>
+    /// <remarks>
+    /// The returned time is UTC, not local.
+    /// </remarks>
+    public override DateTime? LastAccessedTime { get; }
 
     public override DateTime? ArchivedTime => null;
 
     public override bool IsEncrypted =>
-        FlagUtility.HasFlag(_filePart.Header.Flags, HeaderFlags.Encrypted);
+        FlagUtility.HasFlag(_filePart?.Header.Flags ?? HeaderFlags.None, HeaderFlags.Encrypted);
 
-    public override bool IsDirectory => _filePart.Header.IsDirectory;
+    public override bool IsDirectory => _filePart?.Header.IsDirectory ?? false;
 
     public override bool IsSplitAfter => false;
 
-    internal override IEnumerable<FilePart> Parts => _filePart.AsEnumerable<FilePart>();
+    internal override IEnumerable<FilePart> Parts => _filePart.Empty();
 }

src/SharpCompress/Common/Zip/ZipFilePart.cs

@@ -7,8 +7,10 @@ using SharpCompress.Compressors;
 using SharpCompress.Compressors.BZip2;
 using SharpCompress.Compressors.Deflate;
 using SharpCompress.Compressors.Deflate64;
+using SharpCompress.Compressors.Explode;
 using SharpCompress.Compressors.LZMA;
 using SharpCompress.Compressors.PPMd;
+using SharpCompress.Compressors.Reduce;
 using SharpCompress.Compressors.Shrink;
 using SharpCompress.Compressors.Xz;
 using SharpCompress.IO;
@@ -29,7 +31,7 @@ internal abstract class ZipFilePart : FilePart
     internal Stream BaseStream { get; }
     internal ZipFileEntry Header { get; set; }
 
-    internal override string FilePartName => Header.Name;
+    internal override string? FilePartName => Header.Name;
 
     internal override Stream GetCompressedStream()
     {
@@ -89,6 +91,32 @@ internal abstract class ZipFilePart : FilePart
                     Header.UncompressedSize
                 );
             }
+            case ZipCompressionMethod.Reduce1:
+            {
+                return new ReduceStream(stream, Header.CompressedSize, Header.UncompressedSize, 1);
+            }
+            case ZipCompressionMethod.Reduce2:
+            {
+                return new ReduceStream(stream, Header.CompressedSize, Header.UncompressedSize, 2);
+            }
+            case ZipCompressionMethod.Reduce3:
+            {
+                return new ReduceStream(stream, Header.CompressedSize, Header.UncompressedSize, 3);
+            }
+            case ZipCompressionMethod.Reduce4:
+            {
+                return new ReduceStream(stream, Header.CompressedSize, Header.UncompressedSize, 4);
+            }
+            case ZipCompressionMethod.Explode:
+            {
+                return new ExplodeStream(
+                    stream,
+                    Header.CompressedSize,
+                    Header.UncompressedSize,
+                    Header.Flags
+                );
+            }
+
             case ZipCompressionMethod.Deflate:
             {
                 return new DeflateStream(stream, CompressionMode.Decompress);
@@ -203,6 +231,10 @@ internal abstract class ZipFilePart : FilePart
             {
                 case ZipCompressionMethod.None:
                 case ZipCompressionMethod.Shrink:
+                case ZipCompressionMethod.Reduce1:
+                case ZipCompressionMethod.Reduce2:
+                case ZipCompressionMethod.Reduce3:
+                case ZipCompressionMethod.Reduce4:
                 case ZipCompressionMethod.Deflate:
                 case ZipCompressionMethod.Deflate64:
                 case ZipCompressionMethod.BZip2:

src/SharpCompress/Common/Zip/ZipHeaderFactory.cs

@@ -55,7 +55,13 @@ internal class ZipHeaderFactory
             }
             case POST_DATA_DESCRIPTOR:
             {
-                if (FlagUtility.HasFlag(_lastEntryHeader!.Flags, HeaderFlags.UsePostDataDescriptor))
+                if (
+                    _lastEntryHeader != null
+                    && FlagUtility.HasFlag(
+                        _lastEntryHeader.NotNull().Flags,
+                        HeaderFlags.UsePostDataDescriptor
+                    )
+                )
                 {
                     _lastEntryHeader.Crc = reader.ReadUInt32();
                     _lastEntryHeader.CompressedSize = zip64

src/SharpCompress/Compressors/ArcLzw/ArcLzwStream.cs

@@ -0,0 +1,199 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using SharpCompress.Compressors.RLE90;
+using SharpCompress.Compressors.Squeezed;
+
+public partial class ArcLzwStream : Stream
+{
+    private Stream _stream;
+    private bool _processed;
+    private bool _useCrunched;
+    private int _compressedSize;
+
+    private const int BITS = 12;
+    private const int CRUNCH_BITS = 12;
+    private const int SQUASH_BITS = 13;
+    private const int INIT_BITS = 9;
+    private const ushort FIRST = 257;
+    private const ushort CLEAR = 256;
+
+    private ushort oldcode;
+    private byte finchar;
+    private int n_bits;
+    private ushort maxcode;
+    private ushort[] prefix = new ushort[8191];
+    private byte[] suffix = new byte[8191];
+    private bool clearFlag;
+    private Stack<byte> stack = new Stack<byte>();
+    private ushort freeEnt;
+    private ushort maxcodemax;
+
+    public ArcLzwStream(Stream stream, int compressedSize, bool useCrunched = true)
+    {
+        _stream = stream;
+        _useCrunched = useCrunched;
+        _compressedSize = compressedSize;
+
+        oldcode = 0;
+        finchar = 0;
+        n_bits = 0;
+        maxcode = 0;
+        clearFlag = false;
+        freeEnt = FIRST;
+        maxcodemax = 0;
+    }
+
+    private ushort? GetCode(BitReader reader)
+    {
+        if (clearFlag || freeEnt > maxcode)
+        {
+            if (freeEnt > maxcode)
+            {
+                n_bits++;
+                maxcode = (n_bits == BITS) ? maxcodemax : (ushort)((1 << n_bits) - 1);
+            }
+            if (clearFlag)
+            {
+                clearFlag = false;
+                n_bits = INIT_BITS;
+                maxcode = (ushort)((1 << n_bits) - 1);
+            }
+        }
+        return (ushort?)reader.ReadBits(n_bits);
+    }
+
+    public List<byte> Decompress(byte[] input, bool useCrunched)
+    {
+        var result = new List<byte>();
+        int bits = useCrunched ? CRUNCH_BITS : SQUASH_BITS;
+
+        if (useCrunched)
+        {
+            if (input[0] != BITS)
+            {
+                throw new InvalidDataException($"File packed with {input[0]}, expected {BITS}.");
+            }
+
+            input = input.Skip(1).ToArray();
+        }
+
+        maxcodemax = (ushort)(1 << bits);
+        clearFlag = false;
+        n_bits = INIT_BITS;
+        maxcode = (ushort)((1 << n_bits) - 1);
+
+        for (int i = 0; i < 256; i++)
+        {
+            suffix[i] = (byte)i;
+        }
+
+        var reader = new BitReader(input);
+        freeEnt = FIRST;
+
+        if (GetCode(reader) is ushort old)
+        {
+            oldcode = old;
+            finchar = (byte)oldcode;
+            result.Add(finchar);
+        }
+
+        while (GetCode(reader) is ushort code)
+        {
+            if (code == CLEAR)
+            {
+                Array.Clear(prefix, 0, prefix.Length);
+                clearFlag = true;
+                freeEnt = (ushort)(FIRST - 1);
+
+                if (GetCode(reader) is ushort c)
+                {
+                    code = c;
+                }
+                else
+                {
+                    break;
+                }
+            }
+
+            ushort incode = code;
+
+            if (code >= freeEnt)
+            {
+                stack.Push(finchar);
+                code = oldcode;
+            }
+
+            while (code >= 256)
+            {
+                stack.Push(suffix[code]);
+                code = prefix[code];
+            }
+
+            finchar = suffix[code];
+            stack.Push(finchar);
+
+            while (stack.Count > 0)
+            {
+                result.Add(stack.Pop());
+            }
+            code = freeEnt;
+            if (code < maxcodemax)
+            {
+                prefix[code] = oldcode;
+                suffix[code] = finchar;
+                freeEnt = (ushort)(code + 1);
+            }
+
+            oldcode = incode;
+        }
+
+        return result;
+    }
+
+    // Stream base class implementation
+    public override bool CanRead => true;
+    public override bool CanSeek => false;
+    public override bool CanWrite => false;
+    public override long Length => throw new NotImplementedException();
+    public override long Position
+    {
+        get => _stream.Position;
+        set => throw new NotImplementedException();
+    }
+
+    public override void Flush() => throw new NotImplementedException();
+
+    public override int Read(byte[] buffer, int offset, int count)
+    {
+        if (_processed)
+        {
+            return 0;
+        }
+        _processed = true;
+        var data = new byte[_compressedSize];
+        _stream.Read(data, 0, _compressedSize);
+        var decoded = Decompress(data, _useCrunched);
+        var result = decoded.Count();
+        if (_useCrunched)
+        {
+            var unpacked = RLE.UnpackRLE(decoded.ToArray());
+            unpacked.CopyTo(buffer, 0);
+            result = unpacked.Count;
+        }
+        else
+        {
+            decoded.CopyTo(buffer, 0);
+        }
+        return result;
+    }
+
+    public override long Seek(long offset, SeekOrigin origin) =>
+        throw new NotImplementedException();
+
+    public override void SetLength(long value) => throw new NotImplementedException();
+
+    public override void Write(byte[] buffer, int offset, int count) =>
+        throw new NotImplementedException();
+}

src/SharpCompress/Compressors/ArcLzw/BitReader.cs

@@ -0,0 +1,56 @@
+using System;
+
+public partial class ArcLzwStream
+{
+    public class BitReader
+    {
+        private readonly byte[] data;
+        private int bitPosition;
+        private int bytePosition;
+
+        public BitReader(byte[] inputData)
+        {
+            data = inputData;
+            bitPosition = 0;
+            bytePosition = 0;
+        }
+
+        public int? ReadBits(int bitCount)
+        {
+            if (bitCount <= 0 || bitCount > 16)
+                throw new ArgumentOutOfRangeException(
+                    nameof(bitCount),
+                    "Bit count must be between 1 and 16"
+                );
+
+            if (bytePosition >= data.Length)
+                return null;
+
+            int result = 0;
+            int bitsRead = 0;
+
+            while (bitsRead < bitCount)
+            {
+                if (bytePosition >= data.Length)
+                    return null;
+
+                int bitsAvailable = 8 - bitPosition;
+                int bitsToRead = Math.Min(bitCount - bitsRead, bitsAvailable);
+
+                int mask = (1 << bitsToRead) - 1;
+                result |= ((data[bytePosition] >> bitPosition) & mask) << bitsRead;
+
+                bitPosition += bitsToRead;
+                bitsRead += bitsToRead;
+
+                if (bitPosition >= 8)
+                {
+                    bitPosition = 0;
+                    bytePosition++;
+                }
+            }
+
+            return (ushort)result;
+        }
+    }
+}

src/SharpCompress/Compressors/BZip2/BZip2Constants.cs

@@ -555,6 +555,6 @@ internal class BZip2Constants
         858,
         364,
         936,
-        638
+        638,
     };
 }

src/SharpCompress/Compressors/BZip2/BZip2Stream.cs

@@ -69,7 +69,7 @@ public sealed class BZip2Stream : Stream
 
     public override void SetLength(long value) => stream.SetLength(value);
 
-#if !NETFRAMEWORK && !NETSTANDARD2_0
+#if !NETFRAMEWORK&& !NETSTANDARD2_0
 
     public override int Read(Span<byte> buffer) => stream.Read(buffer);