Native .tar extraction in Powershell

Question

I have a .tar.gz file that I need to extract. I've handled the gunzip bit with the GzipStream object from System.IO.Compression, but I couldn't find anything for dealing with tarballs in that namespace. Is there a way to deal with .tar files natively in Powershell? Note that it's only important that I be able to call any such function/method/object construction/system binary from a Powershell script; it doesn't need to actually be written in powershell. (If it matters I'm using 64-bit windows 10)

P.S. please don't say "use 7zip"; that's not native

Answer 1

I believe tar has been added as a native function in Windows 10 since the posting of this.

From the command prompt or PowerShell in Windows 10 I can run

tar -xvzf .\whatever.tar.gz

Note that the .\ was added after auto-completing by the use of tab in PowerShell, but I think it should work without that.

There may be some underlying differences between this function and its Unix implementation (since it is on Windows after all), but it worked for me.

Answer 2

Update in 2019:

As pointed out in other answers, BSD tar was added to Windows 10 as a built-in command in 2018. This answer is still applicable if you need to support earlier versions of Windows.

---

I'm fairly sure that Windows 10 did not have support for extracting tar files by default prior to 2018.

1. The quick easy solution for (early versions of) Windows 10

If you can expect the script to have access to an active Internet connection, then you can simply get 7Zip support using the built-in package manager. This solution:

• Is entirely automated via script (does not require user interaction)
• Does not require administrator privileges
• Only installs the 7Zip support module if it isn't already available

Here it is:

function Expand-Tar($tarFile, $dest) {

    if (-not (Get-Command Expand-7Zip -ErrorAction Ignore)) {
        Install-Package -Scope CurrentUser -Force 7Zip4PowerShell > $null
    }

    Expand-7Zip $tarFile $dest
}

To use it:

Expand-Tar archive.tar dest

It does the job but it makes a persistent change to the client system. There is a better, but slightly more involved, solution:

2. The better solution

The better solution is to bundle 7Zip4PowerShell with your script. This solution:

• Is entirely automated via script (does not require user interaction)
• Does not require administrative privileges
• Does not install any software on the client system
• Does not require internet connectivity
• Should work on earlier versions of Windows

a. Download a copy of the 7Zip4PowerShell package

It's distributed under the LGPL-2.1 licence and so it's OK to bundle the package with your product. You should add a note to your documentation that it uses the package and provide a link since you are required to provide access to the source code for GNU licenced products.

Save-Module -Name 7Zip4Powershell -Path .

This will download it to the current directory. It's easiest to do this on Windows 10 but there are instructions on how to add PowerShell Gallery to your system on earlier versions of Windows from the link above.

b. Import the module when you need to extract the tar file

I've made a simple function just to demonstrate how you could do this based on the first solution:

function Expand-Tar($tarFile, $dest) {

    $pathToModule = ".\7Zip4Powershell\1.9.0\7Zip4PowerShell.psd1"

    if (-not (Get-Command Expand-7Zip -ErrorAction Ignore)) {
        Import-Module $pathToModule
    }

    Expand-7Zip $tarFile $dest
}

You'll need to adjust $pathToModule to where the bundled module is actually stored when your script runs, but you should get the idea. I've written this example such that you can simply paste in both of the code blocks above into a PowerShell window and get a working Expand-Tar cmdlet:

Expand-Tar archive.tar dest

Answer 3

Possible workaround:

I have Windows 10 and I wanted to run curl+tar within Powershell but it lacked support. Luckily, I had Ubuntu bash on Windows 10 which comes with curl and tar preinstalled and ran it within that environment, then after download and extracting, I switched back to Powershell to continue whatever I was doing.

Or as @Don Cruickshank mentioned in comment below you can install 7zip support from within PowerShell directly with Install-Package 7Zip4Powershell. The Expand-7zip cmdlet will extract multiple archive formats, including tar.

These workarounds don't solve your particular problem, but for these that are stuck with Windows, might be useful.

Answer 4

Windows 10 since 2017 has tar build in so may run it as usual exe from powershell liketar -xkf $archivePath -C $outDir, or better from pwsh.

Answer 5

It took me some time but here is the solution I've made. Basically TAR is a very simple format but even then it takes some lines of code to deal with it.

Function ConvertTo-ByteString
{
    Param(
    [Parameter(Mandatory = $True, Position = 0, ValueFromPipeline = $True )][byte[]]$Buffer
    )

    # Note: Codepage 28591 returns a 1-to-1 char to byte mapping
    $Encoding = [System.Text.Encoding]::GetEncoding(28591)
    #$BinaryText = [System.Text.Encoding]::Convert('ascii', '28591', $Buffer)
    $BinaryText = [System.Text.Encoding]::ASCII.GetString($Buffer)
    $BinaryText = $BinaryText.Trim(0)
    $BinaryText = $BinaryText.Trim(32)
    $BinaryText = $BinaryText.Trim(0)
    $BinaryText = $BinaryText.Trim(32)
    return $BinaryText
}

Function New-USTARHeaderObject
{
    #Write-Host('[New-USTARHeaderObject]','Creating new header object') -ForegroundColor Cyan
    $Header = New-Object -Type PSObject
    $Header | Add-Member -MemberType NoteProperty -Name name -Value $null
    $Header | Add-Member -MemberType NoteProperty -Name mode -Value $null
    $Header | Add-Member -MemberType NoteProperty -Name uid -Value $null
    $Header | Add-Member -MemberType NoteProperty -Name gid -Value $null
    $Header | Add-Member -MemberType NoteProperty -Name size -Value $null
    $Header | Add-Member -MemberType NoteProperty -Name mtime -Value $null
    $Header | Add-Member -MemberType NoteProperty -Name cksum -Value $null
    $Header | Add-Member -MemberType NoteProperty -Name typeflag -Value $null
    $Header | Add-Member -MemberType NoteProperty -Name linkname -Value $null
    $Header | Add-Member -MemberType NoteProperty -Name magic -Value $null
    $Header | Add-Member -MemberType NoteProperty -Name version -Value $null
    $Header | Add-Member -MemberType NoteProperty -Name uname -Value $null
    $Header | Add-Member -MemberType NoteProperty -Name gname -Value $null
    $Header | Add-Member -MemberType NoteProperty -Name devmajor -Value $null
    $Header | Add-Member -MemberType NoteProperty -Name devminor -Value $null
    $Header | Add-Member -MemberType NoteProperty -Name prefix -Value $null

    return $Header
   
}

Function Fill-USTARHeaderObject
{
    Param(
    [Parameter(Mandatory=$True)][PSObject]$Header,
    [Parameter(Mandatory=$True)][byte[]]$Buffer
    )
    
    #Write-Host('[Fill-USTARHeaderObject]','Filling header object with bytes') -ForegroundColor Cyan
    $Header.name = [string](ConvertTo-ByteString $Buffer[0..99])
    $Header.mode = ConvertTo-ByteString $Buffer[100..107]
    $Header.uid = ConvertTo-ByteString $Buffer[108..115]
    $Header.gid = ConvertTo-ByteString $Buffer[116..123]
    $Header.size = ConvertTo-ByteString $Buffer[124..135]
    $Header.mtime = ConvertTo-ByteString $Buffer[136..147]
    $Header.cksum = ConvertTo-ByteString $Buffer[148..155]
    $Header.typeflag = ConvertTo-ByteString $Buffer[156]
    $Header.linkname = ConvertTo-ByteString $Buffer[157..256]
    $Header.magic = ConvertTo-ByteString $Buffer[257..262]
    $Header.version = ConvertTo-ByteString $Buffer[263..264]
    $Header.uname = ConvertTo-ByteString $Buffer[265..296]
    $Header.gname = ConvertTo-ByteString $Buffer[297..328]
    $Header.devmajor = ConvertTo-ByteString $Buffer[329..336]
    $Header.devminor = ConvertTo-ByteString $Buffer[337..344]
    $Header.prefix = ConvertTo-ByteString $Buffer[345..499]
}


Function Check-IsUSTARHeaderObject
{
    Param(
    [Parameter(Mandatory=$True, Position = 0, ValueFromPipeline = $True)][PSObject]$Header
    )
    $Regex_Numeric = [regex]"^\d+$"
    #Write-Host('[Check-IsUSTARHeaderObject]','Checking if object is actual header') -ForegroundColor Cyan

    #Write-Host("[Mode    ]",$Header.mode,($Regex_Numeric.Matches($Header.mode).Success)) -ForegroundColor Magenta
    #Write-Host("[Size    ]",$Header.size,($Regex_Numeric.Matches($Header.size).Success)) -ForegroundColor Magenta
    #Write-Host("[MTime   ]",$Header.mtime,($Regex_Numeric.Matches($Header.mtime).Success)) -ForegroundColor Magenta
    #Write-Host("[CKSum   ]",$Header.cksum,($Regex_Numeric.Matches($Header.cksum).Success)) -ForegroundColor Magenta
    #Write-Host("[TypeFlag]",$Header.typeflag,($Regex_Numeric.Matches($Header.typeflag).Success)) -ForegroundColor Magenta
    #Write-Host("[Magic   ]",$Header.magic,($Header.magic -eq 'ustar')) -ForegroundColor Magenta

    if (
        ($Regex_Numeric.Matches($Header.mode).Success) -and
        ($Regex_Numeric.Matches($Header.size).Success) -and
        ($Regex_Numeric.Matches($Header.mtime).Success) -and
        ($Regex_Numeric.Matches($Header.cksum).Success) -and
        ($Regex_Numeric.Matches($Header.typeflag).Success) -and
        ($Header.magic -eq 'ustar')
    )
    {
        #Write-Host('[Check-IsUSTARHeaderObject]','TRUE') -ForegroundColor DarkCyan
        return $true
    } else {
        #Write-Host('[Check-IsUSTARHeaderObject]','FALSE') -ForegroundColor DarkCyan
        return $false
    }
}


Function UnTar-File
{
    Param(
    [Parameter(Mandatory=$True)][String]$Source,
    [Parameter(Mandatory=$False)][String]$Destination
    )
   
    #$Source = 'D:\temp\th-dfbase-blacklist.tar'
    $SourceBaseName = (Get-Item $Source).BaseName
    Write-Host('[UnTar-File]','Setting Source',$Source) -ForegroundColor Cyan

    #if destination parameter not given
    if ($Destination -eq "")
    {
        $SourcePath = Split-Path $Source
        $OutFolder = Join-Path -Path $SourcePath -ChildPath $SourceBaseName
    }
    else
    {
        $OutFolder = Join-Path -Path $Destination -ChildPath $SourceBaseName
    }

    Write-Host('[UnTar-File]','Destination Folder',$OutFolder) -ForegroundColor DarkCyan

    $FileStream = New-Object System.IO.FileStream $Source, ([IO.FileMode]::Open), ([IO.FileAccess]::Read), ([IO.FileShare]::Read)

    $BufferSize = 512
    $Buffer = New-Object byte[]($BufferSize)

    Write-Host('[UnTar-File]','Reading Source by', $BufferSize,'bytes') -ForegroundColor Cyan
    while($true)
    {
    
        $read = $FileStream.Read($Buffer, 0, $BufferSize)
        #Write-Host($read) -ForegroundColor Cyan

        if ($read -le 0){break}

        #Try Header
        $Header = New-USTARHeaderObject
        Fill-USTARHeaderObject -Header $Header -Buffer $Buffer

        #if header section
        if (Check-IsUSTARHeaderObject($Header))
        {
            $ItemPath = [IO.Path]::Combine($Header.prefix, $Header.name)
            $ItemPath = $ItemPath.Replace('/','\')

            #if folder type
            if ($Header.typeflag -eq '5')
            {
                $FolderPath = Join-Path -Path $OutFolder -ChildPath $ItemPath
                Write-Host('[UnTar-File]','Creating Folder',$FolderPath) -ForegroundColor Yellow
                New-Item -Path $FolderPath -ItemType Directory -Force | Out-Null
            }
            #if file type
            else
            {
                $FilePath = Join-Path -Path $OutFolder -ChildPath $ItemPath
                Write-Host('[UnTar-File]','Creating File',$FilePath) -ForegroundColor DarkYellow
                if ($OutputFile -ne $null)
                {
                    $OutputFile.Close()
                }
                $OutputFileInfo = New-Object PSObject
                $OutputFileInfo | Add-Member -MemberType NoteProperty -Name name -Value $Header.name
                $OutputFileInfo | Add-Member -MemberType NoteProperty -Name path -Value (Split-Path -Path $FilePath)
                $OutputFileInfo | Add-Member -MemberType NoteProperty -Name size -Value ([Convert]::ToInt32($Header.size, 8))
                $OutputFileInfo | Add-Member -MemberType NoteProperty -Name left2write -Value ([Convert]::ToInt32($Header.size, 8))
                $OutputFileInfo | Add-Member -MemberType NoteProperty -Name mtime -Value ([Convert]::ToInt32($Header.mtime, 8))
                $OutputFile = New-Object System.IO.FileStream $FilePath, ([IO.FileMode]::Create), ([IO.FileAccess]::Write), ([IO.FileShare]::None)
            }
        }
        #if data section
        else
        {
            if ($OutputFileInfo.left2write -ge $BufferSize)
            {
                $WriteSize = $read
            } else {
                $WriteSize = $OutputFileInfo.left2write
            }
            $OutputFile.Write($Buffer, 0, $WriteSize)
            $OutputFileInfo.left2write = ($OutputFileInfo.left2write - $WriteSize)
        }
    }
    $FileStream.Close()
    if ($OutputFile -ne $null)
    {
        $OutputFile.Close()
    }
}


UnTar-File -Source $Tar

Answer 6

So it's been eleven days since I asked this and the general consensus is: "No, there are no native tools in a vanilla window install that can handle tar extraction 'for you'".

This answer comes from Matthias R. Jensen and TessellatingHeckler, who both declined to answer outside of comments (I suspect due to not wanting to say "no" without an intimate knowledge of the entire Windows system architecture, which is fair).

There are certainly scripts and classes and programs you can install, but nothing "native".

Answer 7

This snippet has been working for me, I don't think I have anything installed that it is using. I still have to figure out how to extract the tar that this pull out.

Function DeGZip-File{
    Param(
        $infile
        )
    $outFile = $infile.Substring(0, $infile.LastIndexOfAny('.'))
    $input = New-Object System.IO.FileStream $inFile, ([IO.FileMode]::Open), ([IO.FileAccess]::Read), ([IO.FileShare]::Read)
    $output = New-Object System.IO.FileStream $outFile, ([IO.FileMode]::Create), ([IO.FileAccess]::Write), ([IO.FileShare]::None)
    $gzipStream = New-Object System.IO.Compression.GzipStream $input, ([IO.Compression.CompressionMode]::Decompress)

    $buffer = New-Object byte[](1024)
    while($true){
        $read = $gzipstream.Read($buffer, 0, 1024)
        if ($read -le 0){break}
        $output.Write($buffer, 0, $read)
        }

    $gzipStream.Close()
    $output.Close()
    $input.Close()
}

$infile='D:\[Directory]\[File].tar.gz'

DeGZip-File $infile 

Answer 8

This is the fragment for a PowerShell script:

try
{
    Add-Type -AssemblyName "ICSharpCode.SharpZLib"

    $file = [IO.File]::OpenRead($gzArchiveName)
    $inStream=New-Object -TypeName ICSharpCode.SharpZipLib.GZip.GZipInputStream $file
    $tarIn = New-Object -TypeName ICSharpCode.SharpZipLib.Tar.TarInputStream $inStream
    $archive = [ICSharpCode.SharpZipLib.Tar.TarArchive]::CreateInputTarArchive($tarIn)
    $archive.ExtractContents($WORKDIR)
}
finally
{
    $archive.Close
}

which is equivalent to the code of TarTool.exe utility