Attempt to use native zlib for gzip. Need lower level access

README.md

@@ -31,15 +31,6 @@ I'm always looking for help or ideas. Please submit code or email with ideas. Un
 
 ## Version Log
 
-### Version 0.16.0
-
-* Breaking - [Progress Event Tracking rethink](https://github.com/adamhathcock/sharpcompress/pull/226)
-* Update to VS2017 - [VS2017](https://github.com/adamhathcock/sharpcompress/pull/231) - Framework targets have been changed.
-* New - [Add Zip64 writing](https://github.com/adamhathcock/sharpcompress/pull/211)
-* [Fix invalid/mismatching Zip version flags.](https://github.com/adamhathcock/sharpcompress/issues/164) - This allows nuget/System.IO.Packaging to read zip files generated by SharpCompress
-* [Fix 7Zip directory hiding](https://github.com/adamhathcock/sharpcompress/pull/215/files)
-* [Verify RAR CRC headers](https://github.com/adamhathcock/sharpcompress/pull/220)
-
 ### Version 0.15.2
 
 * [Fix invalid headers](https://github.com/adamhathcock/sharpcompress/pull/210) - fixes an issue creating large-ish zip archives that was introduced with zip64 reading.

appveyor.yml

@@ -11,10 +11,18 @@ branches:
 nuget:
   disable_publish_on_pr: true
 
-build_script:
-- ps: .\build.ps1
+before_build:
+  - cmd: dotnet restore
 
-test: off
+build:
+  parallel: true
+  verbosity: minimal
+
+after_build:
+- dotnet pack "src\SharpCompress\SharpCompress.csproj" -c Release
+
+test_script:
+- dotnet test --no-build .\tests\SharpCompress.Test\SharpCompress.Test.csproj
 
 artifacts:
 - path: src\SharpCompress\bin\Release\*.nupkg

build.cake

@@ -1,51 +0,0 @@
-var target = Argument("target", "Default");
-var tag = Argument("tag", "cake");
-
-Task("Restore")
-  .Does(() =>
-{
-    DotNetCoreRestore(".");
-});
-
-Task("Build")
-  .Does(() =>
-{
-    MSBuild("./sharpcompress.sln", c => c
-            .SetConfiguration("Release")
-            .SetVerbosity(Verbosity.Minimal)
-            .UseToolVersion(MSBuildToolVersion.VS2017));
-});
-
-Task("Test")
-  .Does(() =>
-{
-    var files = GetFiles("tests/**/*.csproj");
-    foreach(var file in files)
-    {
-        DotNetCoreTest(file.ToString());
-    }
-});
-
-Task("Pack")
-    .IsDependentOn("Build")
-    .Does(() => 
-{
-        MSBuild("src/SharpCompress/SharpCompress.csproj", c => c
-            .SetConfiguration("Release")
-            .SetVerbosity(Verbosity.Minimal)
-            .UseToolVersion(MSBuildToolVersion.VS2017)
-            .WithProperty("NoBuild", "true")
-            .WithTarget("Pack"));
-});
-
-Task("Default")
-    .IsDependentOn("Restore")
-    .IsDependentOn("Build")
-    .IsDependentOn("Pack");
-
- Task("RunTests")
-    .IsDependentOn("Restore")
-    .IsDependentOn("Build");
-
-
-RunTarget(target);

build.ps1

@@ -1,228 +0,0 @@
-##########################################################################
-# This is the Cake bootstrapper script for PowerShell.
-# This file was downloaded from https://github.com/cake-build/resources
-# Feel free to change this file to fit your needs.
-##########################################################################
-
-<#
-
-.SYNOPSIS
-This is a Powershell script to bootstrap a Cake build.
-
-.DESCRIPTION
-This Powershell script will download NuGet if missing, restore NuGet tools (including Cake)
-and execute your Cake build script with the parameters you provide.
-
-.PARAMETER Script
-The build script to execute.
-.PARAMETER Target
-The build script target to run.
-.PARAMETER Configuration
-The build configuration to use.
-.PARAMETER Verbosity
-Specifies the amount of information to be displayed.
-.PARAMETER Experimental
-Tells Cake to use the latest Roslyn release.
-.PARAMETER WhatIf
-Performs a dry run of the build script.
-No tasks will be executed.
-.PARAMETER Mono
-Tells Cake to use the Mono scripting engine.
-.PARAMETER SkipToolPackageRestore
-Skips restoring of packages.
-.PARAMETER ScriptArgs
-Remaining arguments are added here.
-
-.LINK
-http://cakebuild.net
-
-#>
-
-[CmdletBinding()]
-Param(
-    [string]$Script = "build.cake",
-    [string]$Target = "Default",
-    [ValidateSet("Release", "Debug")]
-    [string]$Configuration = "Release",
-    [ValidateSet("Quiet", "Minimal", "Normal", "Verbose", "Diagnostic")]
-    [string]$Verbosity = "Verbose",
-    [switch]$Experimental,
-    [Alias("DryRun","Noop")]
-    [switch]$WhatIf,
-    [switch]$Mono,
-    [switch]$SkipToolPackageRestore,
-    [Parameter(Position=0,Mandatory=$false,ValueFromRemainingArguments=$true)]
-    [string[]]$ScriptArgs
-)
-
-[Reflection.Assembly]::LoadWithPartialName("System.Security") | Out-Null
-function MD5HashFile([string] $filePath)
-{
-    if ([string]::IsNullOrEmpty($filePath) -or !(Test-Path $filePath -PathType Leaf))
-    {
-        return $null
-    }
-
-    [System.IO.Stream] $file = $null;
-    [System.Security.Cryptography.MD5] $md5 = $null;
-    try
-    {
-        $md5 = [System.Security.Cryptography.MD5]::Create()
-        $file = [System.IO.File]::OpenRead($filePath)
-        return [System.BitConverter]::ToString($md5.ComputeHash($file))
-    }
-    finally
-    {
-        if ($file -ne $null)
-        {
-            $file.Dispose()
-        }
-    }
-}
-
-Write-Host "Preparing to run build script..."
-
-if(!$PSScriptRoot){
-    $PSScriptRoot = Split-Path $MyInvocation.MyCommand.Path -Parent
-}
-
-$TOOLS_DIR = Join-Path $PSScriptRoot "tools"
-$ADDINS_DIR = Join-Path $TOOLS_DIR "addins"
-$MODULES_DIR = Join-Path $TOOLS_DIR "modules"
-$NUGET_EXE = Join-Path $TOOLS_DIR "nuget.exe"
-$CAKE_EXE = Join-Path $TOOLS_DIR "Cake/Cake.exe"
-$NUGET_URL = "https://dist.nuget.org/win-x86-commandline/latest/nuget.exe"
-$PACKAGES_CONFIG = Join-Path $TOOLS_DIR "packages.config"
-$PACKAGES_CONFIG_MD5 = Join-Path $TOOLS_DIR "packages.config.md5sum"
-$ADDINS_PACKAGES_CONFIG = Join-Path $ADDINS_DIR "packages.config"
-$MODULES_PACKAGES_CONFIG = Join-Path $MODULES_DIR "packages.config"
-
-# Should we use mono?
-$UseMono = "";
-if($Mono.IsPresent) {
-    Write-Verbose -Message "Using the Mono based scripting engine."
-    $UseMono = "-mono"
-}
-
-# Should we use the new Roslyn?
-$UseExperimental = "";
-if($Experimental.IsPresent -and !($Mono.IsPresent)) {
-    Write-Verbose -Message "Using experimental version of Roslyn."
-    $UseExperimental = "-experimental"
-}
-
-# Is this a dry run?
-$UseDryRun = "";
-if($WhatIf.IsPresent) {
-    $UseDryRun = "-dryrun"
-}
-
-# Make sure tools folder exists
-if ((Test-Path $PSScriptRoot) -and !(Test-Path $TOOLS_DIR)) {
-    Write-Verbose -Message "Creating tools directory..."
-    New-Item -Path $TOOLS_DIR -Type directory | out-null
-}
-
-# Make sure that packages.config exist.
-if (!(Test-Path $PACKAGES_CONFIG)) {
-    Write-Verbose -Message "Downloading packages.config..."
-    try { (New-Object System.Net.WebClient).DownloadFile("http://cakebuild.net/download/bootstrapper/packages", $PACKAGES_CONFIG) } catch {
-        Throw "Could not download packages.config."
-    }
-}
-
-# Try find NuGet.exe in path if not exists
-if (!(Test-Path $NUGET_EXE)) {
-    Write-Verbose -Message "Trying to find nuget.exe in PATH..."
-    $existingPaths = $Env:Path -Split ';' | Where-Object { (![string]::IsNullOrEmpty($_)) -and (Test-Path $_ -PathType Container) }
-    $NUGET_EXE_IN_PATH = Get-ChildItem -Path $existingPaths -Filter "nuget.exe" | Select -First 1
-    if ($NUGET_EXE_IN_PATH -ne $null -and (Test-Path $NUGET_EXE_IN_PATH.FullName)) {
-        Write-Verbose -Message "Found in PATH at $($NUGET_EXE_IN_PATH.FullName)."
-        $NUGET_EXE = $NUGET_EXE_IN_PATH.FullName
-    }
-}
-
-# Try download NuGet.exe if not exists
-if (!(Test-Path $NUGET_EXE)) {
-    Write-Verbose -Message "Downloading NuGet.exe..."
-    try {
-        (New-Object System.Net.WebClient).DownloadFile($NUGET_URL, $NUGET_EXE)
-    } catch {
-        Throw "Could not download NuGet.exe."
-    }
-}
-
-# Save nuget.exe path to environment to be available to child processed
-$ENV:NUGET_EXE = $NUGET_EXE
-
-# Restore tools from NuGet?
-if(-Not $SkipToolPackageRestore.IsPresent) {
-    Push-Location
-    Set-Location $TOOLS_DIR
-
-    # Check for changes in packages.config and remove installed tools if true.
-    [string] $md5Hash = MD5HashFile($PACKAGES_CONFIG)
-    if((!(Test-Path $PACKAGES_CONFIG_MD5)) -Or
-      ($md5Hash -ne (Get-Content $PACKAGES_CONFIG_MD5 ))) {
-        Write-Verbose -Message "Missing or changed package.config hash..."
-        Remove-Item * -Recurse -Exclude packages.config,nuget.exe
-    }
-
-    Write-Verbose -Message "Restoring tools from NuGet..."
-    $NuGetOutput = Invoke-Expression "&`"$NUGET_EXE`" install -ExcludeVersion -OutputDirectory `"$TOOLS_DIR`""
-
-    if ($LASTEXITCODE -ne 0) {
-        Throw "An error occured while restoring NuGet tools."
-    }
-    else
-    {
-        $md5Hash | Out-File $PACKAGES_CONFIG_MD5 -Encoding "ASCII"
-    }
-    Write-Verbose -Message ($NuGetOutput | out-string)
-    
-    Pop-Location
-}
-
-# Restore addins from NuGet
-if (Test-Path $ADDINS_PACKAGES_CONFIG) {
-    Push-Location
-    Set-Location $ADDINS_DIR
-
-    Write-Verbose -Message "Restoring addins from NuGet..."
-    $NuGetOutput = Invoke-Expression "&`"$NUGET_EXE`" install -ExcludeVersion -OutputDirectory `"$ADDINS_DIR`""
-
-    if ($LASTEXITCODE -ne 0) {
-        Throw "An error occured while restoring NuGet addins."
-    }
-
-    Write-Verbose -Message ($NuGetOutput | out-string)
-
-    Pop-Location
-}
-
-# Restore modules from NuGet
-if (Test-Path $MODULES_PACKAGES_CONFIG) {
-    Push-Location
-    Set-Location $MODULES_DIR
-
-    Write-Verbose -Message "Restoring modules from NuGet..."
-    $NuGetOutput = Invoke-Expression "&`"$NUGET_EXE`" install -ExcludeVersion -OutputDirectory `"$MODULES_DIR`""
-
-    if ($LASTEXITCODE -ne 0) {
-        Throw "An error occured while restoring NuGet modules."
-    }
-
-    Write-Verbose -Message ($NuGetOutput | out-string)
-
-    Pop-Location
-}
-
-# Make sure that Cake has been installed.
-if (!(Test-Path $CAKE_EXE)) {
-    Throw "Could not find Cake.exe at $CAKE_EXE"
-}
-
-# Start Cake
-Write-Host "Running build script..."
-Invoke-Expression "& `"$CAKE_EXE`" `"$Script`" -target=`"$Target`" -configuration=`"$Configuration`" -verbosity=`"$Verbosity`" $UseMono $UseDryRun $UseExperimental $ScriptArgs"
-exit $LASTEXITCODE

src/SharpCompress/Compressors/Deflate/GZipStream.NetStandard13.cs

@@ -0,0 +1,525 @@
+#if NETSTANDARD1_3
+using System;
+using System.Collections.Generic;
+using System.IO;
+using SharpCompress.Common;
+using SharpCompress.Converters;
+
+namespace SharpCompress.Compressors.Deflate
+{
+    public class GZipStream : Stream
+    {
+        private enum Mode
+        {
+            Unknown,
+            Reader,
+            Writer
+        }
+
+        internal static readonly DateTime UnixEpoch = new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc);
+
+        public DateTime? LastModified { get; set; }
+        private byte[] _buf1 = new byte[1];
+        
+        private System.IO.Compression.DeflateStream BaseStream;
+        private bool disposed;
+        private Mode mode;
+
+
+        private string _GzipFileName;
+        private string _GzipComment;
+        private DateTime _GzipMtime;
+        private int _gzipHeaderByteCount;
+
+        public GZipStream(Stream stream, CompressionMode mode)
+            : this(stream, mode, CompressionLevel.Default, false)
+        {
+        }
+
+        public GZipStream(Stream stream, CompressionMode mode, CompressionLevel level)
+            : this(stream, mode, level, false)
+        {
+        }
+
+        public GZipStream(Stream stream, CompressionMode mode, bool leaveOpen)
+            : this(stream, mode, CompressionLevel.Default, leaveOpen)
+        {
+        }
+
+        public GZipStream(Stream stream, CompressionMode mode, CompressionLevel level, bool leaveOpen)
+        {
+            if (mode == CompressionMode.Decompress)
+            {
+                BaseStream = new System.IO.Compression.DeflateStream(stream, System.IO.Compression.CompressionMode.Decompress, leaveOpen);
+            }
+            else
+            {
+                System.IO.Compression.CompressionLevel l;
+                switch (level)
+                {
+                    case CompressionLevel.BestSpeed:
+                    {
+                        l = System.IO.Compression.CompressionLevel.Fastest;
+                        break;
+                    }
+                    case CompressionLevel.None:
+                    {
+                        l = System.IO.Compression.CompressionLevel.NoCompression;
+                        break;
+                    }
+                    default:
+                    {
+                        l = System.IO.Compression.CompressionLevel.Optimal;
+                        break;
+                    }
+                }
+
+                BaseStream = new System.IO.Compression.DeflateStream(stream, l, leaveOpen);
+
+
+            }
+        }
+
+        #region Stream methods
+
+        /// <summary>
+        /// Indicates whether the stream can be read.
+        /// </summary>
+        /// <remarks>
+        /// The return value depends on whether the captive stream supports reading.
+        /// </remarks>
+        public override bool CanRead
+        {
+            get
+            {
+                if (disposed)
+                {
+                    throw new ObjectDisposedException("GZipStream");
+                }
+                return BaseStream.CanRead;
+            }
+        }
+
+        /// <summary>
+        /// Indicates whether the stream supports Seek operations.
+        /// </summary>
+        /// <remarks>
+        /// Always returns false.
+        /// </remarks>
+        public override bool CanSeek => false;
+
+        /// <summary>
+        /// Indicates whether the stream can be written.
+        /// </summary>
+        /// <remarks>
+        /// The return value depends on whether the captive stream supports writing.
+        /// </remarks>
+        public override bool CanWrite
+        {
+            get
+            {
+                if (disposed)
+                {
+                    throw new ObjectDisposedException("GZipStream");
+                }
+                return BaseStream.CanWrite;
+            }
+        }
+
+        /// <summary>
+        /// Reading this property always throws a <see cref="NotImplementedException"/>.
+        /// </summary>
+        public override long Length => throw new NotSupportedException();
+
+        /// <summary>
+        ///   The position of the stream pointer.
+        /// </summary>
+        ///
+        /// <remarks>
+        ///   Setting this property always throws a <see
+        ///   cref="NotImplementedException"/>. Reading will return the total bytes
+        ///   written out, if used in writing, or the total bytes read in, if used in
+        ///   reading.  The count may refer to compressed bytes or uncompressed bytes,
+        ///   depending on how you've used the stream.
+        /// </remarks>
+        public override long Position
+        {
+            get
+            {
+                switch (mode)
+                {
+                    case Mode.Writer:
+                        return BaseStream.Position + _gzipHeaderByteCount;
+                    case Mode.Reader:
+                        return BaseStream.Position + _gzipHeaderByteCount;
+                    default:
+                        return 0;
+                }
+            }
+
+            set => throw new NotSupportedException();
+        }
+
+        /// <summary>
+        /// Dispose the stream.
+        /// </summary>
+        /// <remarks>
+        /// This may or may not result in a <c>Close()</c> call on the captive stream.
+        /// See the doc on constructors that take a <c>leaveOpen</c> parameter for more information.
+        /// </remarks>
+        protected override void Dispose(bool disposing)
+        {
+            try
+            {
+                if (!disposed)
+                {
+                    if (disposing && (BaseStream != null))
+                    {
+                        BaseStream.Dispose();;
+                    }
+                    disposed = true;
+                }
+            }
+            finally
+            {
+                base.Dispose(disposing);
+            }
+        }
+
+        /// <summary>
+        /// Flush the stream.
+        /// </summary>
+        public override void Flush()
+        {
+            if (disposed)
+            {
+                throw new ObjectDisposedException("GZipStream");
+            }
+            BaseStream.Flush();
+        }
+
+        /// <summary>
+        ///   Read and decompress data from the source stream.
+        /// </summary>
+        ///
+        /// <remarks>
+        ///   With a <c>GZipStream</c>, decompression is done through reading.
+        /// </remarks>
+        ///
+        /// <example>
+        /// <code>
+        /// byte[] working = new byte[WORKING_BUFFER_SIZE];
+        /// using (System.IO.Stream input = System.IO.File.OpenRead(_CompressedFile))
+        /// {
+        ///     using (Stream decompressor= new Ionic.Zlib.GZipStream(input, CompressionMode.Decompress, true))
+        ///     {
+        ///         using (var output = System.IO.File.Create(_DecompressedFile))
+        ///         {
+        ///             int n;
+        ///             while ((n= decompressor.Read(working, 0, working.Length)) !=0)
+        ///             {
+        ///                 output.Write(working, 0, n);
+        ///             }
+        ///         }
+        ///     }
+        /// }
+        /// </code>
+        /// </example>
+        /// <param name="buffer">The buffer into which the decompressed data should be placed.</param>
+        /// <param name="offset">the offset within that data array to put the first byte read.</param>
+        /// <param name="count">the number of bytes to read.</param>
+        /// <returns>the number of bytes actually read</returns>
+        public override int Read(byte[] buffer, int offset, int count)
+        {
+            if (disposed)
+            {
+                throw new ObjectDisposedException("GZipStream");
+            }
+            int n = BaseStream.Read(buffer, offset, count);
+
+            // Console.WriteLine("GZipStream::Read(buffer, off({0}), c({1}) = {2}", offset, count, n);
+            // Console.WriteLine( Util.FormatByteArray(buffer, offset, n) );
+
+            if (mode == Mode.Unknown)
+            {
+                _gzipHeaderByteCount = _ReadAndValidateGzipHeader();
+                mode = Mode.Reader;
+                FileName = _GzipFileName;
+                Comment = _GzipComment;
+            }
+            return n;
+        }
+
+
+        private int _ReadAndValidateGzipHeader()
+        {
+            int totalBytesRead = 0;
+
+            // read the header on the first read
+            byte[] header = new byte[10];
+            int n = BaseStream.Read(header, 0, header.Length);
+
+            // workitem 8501: handle edge case (decompress empty stream)
+            if (n == 0)
+            {
+                return 0;
+            }
+
+            if (n != 10)
+            {
+                throw new ZlibException("Not a valid GZIP stream.");
+            }
+
+            if (header[0] != 0x1F || header[1] != 0x8B || header[2] != 8)
+            {
+                throw new ZlibException("Bad GZIP header.");
+            }
+
+            Int32 timet = DataConverter.LittleEndian.GetInt32(header, 4);
+            _GzipMtime = UnixEpoch.AddSeconds(timet);
+            totalBytesRead += n;
+            if ((header[3] & 0x04) == 0x04)
+            {
+                // read and discard extra field
+                n = BaseStream.Read(header, 0, 2); // 2-byte length field
+                totalBytesRead += n;
+
+                Int16 extraLength = (Int16)(header[0] + header[1] * 256);
+                byte[] extra = new byte[extraLength];
+                n = BaseStream.Read(extra, 0, extra.Length);
+                if (n != extraLength)
+                {
+                    throw new ZlibException("Unexpected end-of-file reading GZIP header.");
+                }
+                totalBytesRead += n;
+            }
+            if ((header[3] & 0x08) == 0x08)
+            {
+                _GzipFileName = ReadZeroTerminatedString();
+            }
+            if ((header[3] & 0x10) == 0x010)
+            {
+                _GzipComment = ReadZeroTerminatedString();
+            }
+            if ((header[3] & 0x02) == 0x02)
+            {
+                Read(_buf1, 0, 1); // CRC16, ignore
+            }
+
+            return totalBytesRead;
+        }
+
+        private string ReadZeroTerminatedString()
+        {
+            var list = new List<byte>();
+            bool done = false;
+            do
+            {
+                // workitem 7740
+                int n = BaseStream.Read(_buf1, 0, 1);
+                if (n != 1)
+                {
+                    throw new ZlibException("Unexpected EOF reading GZIP header.");
+                }
+                if (_buf1[0] == 0)
+                {
+                    done = true;
+                }
+                else
+                {
+                    list.Add(_buf1[0]);
+                }
+            }
+            while (!done);
+            byte[] a = list.ToArray();
+            return ArchiveEncoding.Default.GetString(a, 0, a.Length);
+        }
+
+        /// <summary>
+        ///   Calling this method always throws a <see cref="NotImplementedException"/>.
+        /// </summary>
+        /// <param name="offset">irrelevant; it will always throw!</param>
+        /// <param name="origin">irrelevant; it will always throw!</param>
+        /// <returns>irrelevant!</returns>
+        public override long Seek(long offset, SeekOrigin origin)
+        {
+            throw new NotSupportedException();
+        }
+
+        /// <summary>
+        ///   Calling this method always throws a <see cref="NotImplementedException"/>.
+        /// </summary>
+        /// <param name="value">irrelevant; this method will always throw!</param>
+        public override void SetLength(long value)
+        {
+            throw new NotSupportedException();
+        }
+
+        /// <summary>
+        ///   Write data to the stream.
+        /// </summary>
+        ///
+        /// <remarks>
+        /// <para>
+        ///   If you wish to use the <c>GZipStream</c> to compress data while writing,
+        ///   you can create a <c>GZipStream</c> with <c>CompressionMode.Compress</c>, and a
+        ///   writable output stream.  Then call <c>Write()</c> on that <c>GZipStream</c>,
+        ///   providing uncompressed data as input.  The data sent to the output stream
+        ///   will be the compressed form of the data written.
+        /// </para>
+        ///
+        /// <para>
+        ///   A <c>GZipStream</c> can be used for <c>Read()</c> or <c>Write()</c>, but not
+        ///   both. Writing implies compression.  Reading implies decompression.
+        /// </para>
+        ///
+        /// </remarks>
+        /// <param name="buffer">The buffer holding data to write to the stream.</param>
+        /// <param name="offset">the offset within that data array to find the first byte to write.</param>
+        /// <param name="count">the number of bytes to write.</param>
+        public override void Write(byte[] buffer, int offset, int count)
+        {
+            if (disposed)
+            {
+                throw new ObjectDisposedException("GZipStream");
+            }
+            if (mode == Mode.Unknown)
+            {
+                // first write in compression, therefore, emit the GZIP header
+                _gzipHeaderByteCount = EmitHeader();
+                mode = Mode.Writer;
+            }
+
+            BaseStream.Write(buffer, offset, count);
+        }
+
+        #endregion
+
+        public string Comment
+        {
+            get => _GzipComment;
+            set
+            {
+                if (disposed)
+                {
+                    throw new ObjectDisposedException("GZipStream");
+                }
+                _GzipComment = value;
+            }
+        }
+
+        public string FileName
+        {
+            get => _GzipFileName;
+            set
+            {
+                if (disposed)
+                {
+                    throw new ObjectDisposedException("GZipStream");
+                }
+                _GzipFileName = value;
+                if (_GzipFileName == null)
+                {
+                    return;
+                }
+                if (_GzipFileName.IndexOf("/") != -1)
+                {
+                    _GzipFileName = _GzipFileName.Replace("/", "\\");
+                }
+                if (_GzipFileName.EndsWith("\\"))
+                {
+                    throw new InvalidOperationException("Illegal filename");
+                }
+
+                var index = _GzipFileName.IndexOf("\\");
+                if (index != -1)
+                {
+                    // trim any leading path
+                    int length = _GzipFileName.Length;
+                    int num = length;
+                    while (--num >= 0)
+                    {
+                        char c = _GzipFileName[num];
+                        if (c == '\\')
+                        {
+                            _GzipFileName = _GzipFileName.Substring(num + 1, length - num - 1);
+                        }
+                    }
+                }
+            }
+        }
+
+        private int EmitHeader()
+        {
+            byte[] commentBytes = (Comment == null) ? null : ArchiveEncoding.Default.GetBytes(Comment);
+            byte[] filenameBytes = (FileName == null) ? null : ArchiveEncoding.Default.GetBytes(FileName);
+
+            int cbLength = (Comment == null) ? 0 : commentBytes.Length + 1;
+            int fnLength = (FileName == null) ? 0 : filenameBytes.Length + 1;
+
+            int bufferLength = 10 + cbLength + fnLength;
+            var header = new byte[bufferLength];
+            int i = 0;
+
+            // ID
+            header[i++] = 0x1F;
+            header[i++] = 0x8B;
+
+            // compression method
+            header[i++] = 8;
+            byte flag = 0;
+            if (Comment != null)
+            {
+                flag ^= 0x10;
+            }
+            if (FileName != null)
+            {
+                flag ^= 0x8;
+            }
+
+            // flag
+            header[i++] = flag;
+
+            // mtime
+            if (!LastModified.HasValue)
+            {
+                LastModified = DateTime.Now;
+            }
+            TimeSpan delta = LastModified.Value - UnixEpoch;
+            var timet = (Int32)delta.TotalSeconds;
+            DataConverter.LittleEndian.PutBytes(header, i, timet);
+            i += 4;
+
+            // xflg
+            header[i++] = 0; // this field is totally useless
+
+            // OS
+            header[i++] = 0xFF; // 0xFF == unspecified
+
+            // extra field length - only if FEXTRA is set, which it is not.
+            //header[i++]= 0;
+            //header[i++]= 0;
+
+            // filename
+            if (fnLength != 0)
+            {
+                Array.Copy(filenameBytes, 0, header, i, fnLength - 1);
+                i += fnLength - 1;
+                header[i++] = 0; // terminate
+            }
+
+            // comment
+            if (cbLength != 0)
+            {
+                Array.Copy(commentBytes, 0, header, i, cbLength - 1);
+                i += cbLength - 1;
+                header[i++] = 0; // terminate
+            }
+
+            BaseStream.Write(header, 0, header.Length);
+
+            return header.Length; // bytes written
+        }
+    }
+}
+#endif

src/SharpCompress/Compressors/Deflate/GZipStream.cs

@@ -1,3 +1,4 @@
+#if NETSTANDARD1_0
 // GZipStream.cs
 // ------------------------------------------------------------------
 //
@@ -476,4 +477,5 @@ namespace SharpCompress.Compressors.Deflate
             return header.Length; // bytes written
         }
     }
-}
+}
+#endif

src/SharpCompress/SharpCompress.csproj

@@ -7,8 +7,7 @@
     <AssemblyVersion>0.16.0.0</AssemblyVersion>
     <FileVersion>0.16.0.0</FileVersion>
     <Authors>Adam Hathcock</Authors>
-    <TargetFrameworks Condition="'$(LibraryFrameworks)'==''">net45;net35;netstandard1.0;netstandard1.3</TargetFrameworks>
-    <TargetFrameworks Condition="'$(LibraryFrameworks)'!=''">$(LibraryFrameworks)</TargetFrameworks>
+    <TargetFrameworks>netstandard1.0;netstandard1.3</TargetFrameworks>
     <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
     <AssemblyName>SharpCompress</AssemblyName>
@@ -28,8 +27,4 @@
     <DefineConstants>$(DefineConstants);NO_FILE;NO_CRYPTO;SILVERLIGHT</DefineConstants>
   </PropertyGroup>
 
-  <PropertyGroup Condition="'$(TargetFramework)'=='net35'">
-    <DefineConstants>$(DefineConstants);NO_FILE;NO_CRYPTO;SILVERLIGHT</DefineConstants>
-  </PropertyGroup>
-
 </Project>

src/SharpCompress/Writers/Zip/ZipCentralDirectoryEntry.cs

@@ -30,7 +30,7 @@ namespace SharpCompress.Writers.Zip
             var decompressedvalue = zip64 ? uint.MaxValue : (uint)Decompressed;
             var headeroffsetvalue = zip64 ? uint.MaxValue : (uint)HeaderOffset;
             var extralength = zip64 ? (2 + 2 + 8 + 8 + 8 + 4) : 0;
-            var version = (byte)(zip64 ? 45 : 20); // Version 20 required for deflate/encryption
+            var version = (byte)(zip64 ? 45 : 10);
 
             HeaderFlags flags = HeaderFlags.UTF8;
             if (!outputStream.CanSeek)

tests/SharpCompress.Test/ArchiveTests.cs

@@ -95,9 +95,9 @@ namespace SharpCompress.Test
                 ResetScratch();
                 using (var archive = ArchiveFactory.Open(path))
                 {
-                    //archive.EntryExtractionBegin += archive_EntryExtractionBegin;
-                    //archive.FilePartExtractionBegin += archive_FilePartExtractionBegin;
-                    //archive.CompressedBytesRead += archive_CompressedBytesRead;
+                    archive.EntryExtractionBegin += archive_EntryExtractionBegin;
+                    archive.FilePartExtractionBegin += archive_FilePartExtractionBegin;
+                    archive.CompressedBytesRead += archive_CompressedBytesRead;
 
                     foreach (var entry in archive.Entries.Where(entry => !entry.IsDirectory))
                     {
@@ -157,9 +157,9 @@ namespace SharpCompress.Test
                 using (var archive = ArchiveFactory.Open(path))
                 {
                     totalSize = archive.TotalUncompressSize;
-                    //archive.EntryExtractionBegin += Archive_EntryExtractionBeginEx;
-                    //archive.EntryExtractionEnd += Archive_EntryExtractionEndEx;
-                    //archive.CompressedBytesRead += Archive_CompressedBytesReadEx;
+                    archive.EntryExtractionBegin += Archive_EntryExtractionBeginEx;
+                    archive.EntryExtractionEnd += Archive_EntryExtractionEndEx;
+                    archive.CompressedBytesRead += Archive_CompressedBytesReadEx;
 
                     foreach (var entry in archive.Entries.Where(entry => !entry.IsDirectory))
                     {