Merge pull request #614 from adamhathcock/ensure-dest-dir-exists

Ensure destination directory exists.

.github/workflows/dotnetcore.yml

@@ -12,7 +12,7 @@ jobs:
     - uses: actions/checkout@v1
     - uses: actions/setup-dotnet@v1
       with:
-        dotnet-version: 5.0.300
+        dotnet-version: 5.0.400
     - run: dotnet run -p build/build.csproj
     - uses: actions/upload-artifact@v2
       with:

build/build.csproj

@@ -6,7 +6,7 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Bullseye" Version="3.7.0" />
+    <PackageReference Include="Bullseye" Version="3.8.0" />
     <PackageReference Include="Glob" Version="1.1.8" />
     <PackageReference Include="SimpleExec" Version="7.0.0" />
   </ItemGroup>

global.json

@@ -1,5 +1,6 @@
 {
   "sdk": {
-    "version": "5.0.300"
+    "version": "5.0.300",
+    "rollForward": "latestFeature"
   }
 }

src/SharpCompress/Common/ExtractionMethods.cs

@@ -14,14 +14,25 @@ namespace SharpCompress.Common
                                                  Action<string, ExtractionOptions?> write)
         {
             string destinationFileName;
-            string file = Path.GetFileName(entry.Key);
             string fullDestinationDirectoryPath = Path.GetFullPath(destinationDirectory);
+            
+            //check for trailing slash.
+            if (fullDestinationDirectoryPath[fullDestinationDirectoryPath.Length - 1] != Path.DirectorySeparatorChar)
+            {
+                fullDestinationDirectoryPath += Path.DirectorySeparatorChar;
+            }
+
+            if (!Directory.Exists(fullDestinationDirectoryPath))
+            {
+                throw new ExtractionException($"Directory does not exist to extract to: {fullDestinationDirectoryPath}");
+            }
 
             options ??= new ExtractionOptions()
             {
                 Overwrite = true
             };
 
+            string file = Path.GetFileName(entry.Key);
             if (options.ExtractFullPath)
             {
                 string folder = Path.GetDirectoryName(entry.Key)!;

src/SharpCompress/Common/Zip/SeekableZipHeaderFactory.cs

@@ -117,7 +117,8 @@ namespace SharpCompress.Common.Zip
             // Search in reverse
             Array.Reverse(seek);
 
-            var max_search_area = len - MINIMUM_EOCD_LENGTH;
+            // don't exclude the minimum eocd region, otherwise you fail to locate the header in empty zip files
+            var max_search_area = len; // - MINIMUM_EOCD_LENGTH;
 
             for( int pos_from_end = 0; pos_from_end < max_search_area; ++pos_from_end)
             {

src/SharpCompress/SharpCompress.csproj

@@ -2,9 +2,9 @@
   <PropertyGroup>
     <AssemblyTitle>SharpCompress - Pure C# Decompression/Compression</AssemblyTitle>
     <NeutralLanguage>en-US</NeutralLanguage>
-    <VersionPrefix>0.28.3</VersionPrefix>
-    <AssemblyVersion>0.28.3</AssemblyVersion>
-    <FileVersion>0.28.3</FileVersion>
+    <VersionPrefix>0.29.0</VersionPrefix>
+    <AssemblyVersion>0.29.0</AssemblyVersion>
+    <FileVersion>0.29.0</FileVersion>
     <Authors>Adam Hathcock</Authors>
     <TargetFrameworks>netstandard2.0;netstandard2.1;netcoreapp3.1;net5.0</TargetFrameworks>
     <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
@@ -18,7 +18,7 @@
     <PackageLicense>https://github.com/adamhathcock/sharpcompress/blob/master/LICENSE.txt</PackageLicense>
     <GenerateAssemblyTitleAttribute>false</GenerateAssemblyTitleAttribute>
     <GenerateAssemblyProductAttribute>false</GenerateAssemblyProductAttribute>
-    <Description>SharpCompress is a compression library for NET Standard 2.0/2.1//NET 4.6 that can unrar, decompress 7zip, decompress xz, zip/unzip, tar/untar lzip/unlzip, bzip2/unbzip2 and gzip/ungzip with forward-only reading and file random access APIs. Write support for zip/tar/bzip2/gzip is implemented.</Description>
+    <Description>SharpCompress is a compression library for NET Standard 2.0/2.1/NET 5.0 that can unrar, decompress 7zip, decompress xz, zip/unzip, tar/untar lzip/unlzip, bzip2/unbzip2 and gzip/ungzip with forward-only reading and file random access APIs. Write support for zip/tar/bzip2/gzip is implemented.</Description>
     <LangVersion>9</LangVersion>
     <Nullable>enable</Nullable>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>

src/SharpCompress/Writers/Tar/TarWriter.cs

@@ -87,18 +87,15 @@ namespace SharpCompress.Writers.Tar
             header.Name = NormalizeFilename(filename);
             header.Size = realSize;
             header.Write(OutputStream);
+
             size = source.TransferTo(OutputStream);
-            PadTo512(size.Value, false);
+            PadTo512(size.Value);
         }
 
-        private void PadTo512(long size, bool forceZeros)
+        private void PadTo512(long size)
         {
-            int zeros = (int)size % 512;
-            if (zeros == 0 && !forceZeros)
-            {
-                return;
-            }
-            zeros = 512 - zeros;
+            int zeros = unchecked((int)(((size + 511L) & ~511L) - size));
+
             OutputStream.Write(stackalloc byte[zeros]);
         }
 
@@ -108,8 +105,7 @@ namespace SharpCompress.Writers.Tar
             {
                 if (finalizeArchiveOnClose)
                 {
-                    PadTo512(0, true);
-                    PadTo512(0, true);
+                    OutputStream.Write(stackalloc byte[1024]);
                 }
                 switch (OutputStream)
                 {

tests/SharpCompress.Test/SharpCompress.Test.csproj

@@ -12,7 +12,7 @@
     <ProjectReference Include="..\..\src\SharpCompress\SharpCompress.csproj" />
   </ItemGroup>
   <ItemGroup>
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.10.0" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.11.0" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.4.3">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>

tests/SharpCompress.Test/Zip/ZipArchiveTests.cs

@@ -290,6 +290,28 @@ namespace SharpCompress.Test.Zip
             Directory.Delete(SCRATCH_FILES_PATH, true);
         }
 
+        /// <summary>
+        /// Creates an empty zip file and attempts to read it right afterwards. 
+        /// Ensures that parsing file headers works even in that case
+        /// </summary>
+        [Fact]
+        public void Zip_Create_Empty_And_Read()
+        {
+            var archive = ZipArchive.Create();
+
+            var archiveStream = new MemoryStream();
+
+            archive.SaveTo(archiveStream, CompressionType.LZMA);
+
+            archiveStream.Position = 0;
+
+            var readArchive = ArchiveFactory.Open(archiveStream);
+
+            var count = readArchive.Entries.Count();
+
+            Assert.Equal(0, count);
+        }
+
         [Fact]
         public void Zip_Create_New_Add_Remove()
         {