Can not work with archive/tar

[keeword]

Please answer these questions before submitting your issue. Thanks!

What version of Go are you using (go version)?

go version go1.15.8 linux/amd64

What operating system and processor architecture are you using (go env)?

GO111MODULE="on"
GOARCH="amd64"
GOBIN=""
GOCACHE="/root/.cache/go-build"
GOENV="/root/.config/go/env"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOINSECURE=""
GOMODCACHE="/root/go/pkg/mod"
GONOPROXY=""
GONOSUMDB=""
GOOS="linux"
GOPATH="/root/go"
GOPRIVATE=""
GOROOT="/usr/lib/go-1.15"
GOSUMDB="sum.golang.org"
GOTMPDIR=""
GOTOOLDIR="/usr/lib/go-1.15/pkg/tool/linux_amd64"
GCCGO="gccgo"
AR="ar"
CC="gcc"
CXX="g++"
CGO_ENABLED="1"
GOMOD="/root/test/go.mod"
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -m64 -pthread -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build135663132=/tmp/go-build -gno-record-gcc-switches"

What did you do?

I tried to work with package "archive/tar".

package main

import (
	"archive/tar"
	"io"
	"os"

	"github.com/DataDog/zstd"
)

func main() {
	out, err := os.Create("out.tar.zstd")
	if err != nil {
		panic(err)
	}
	defer out.Close()

	in := "infile.txt"
	fi, err := os.Stat(in)
	if err != nil {
		panic(err)
	}

	zw := zstd.NewWriter(out)
	defer zw.Close()

	tw := tar.NewWriter(zw)
	defer tw.Close()

	hdr, err := tar.FileInfoHeader(fi, fi.Name())
	if err != nil {
		panic(err)
	}

	if err := tw.WriteHeader(hdr); err != nil {
		panic(err)
	}

	file, err := os.OpenFile(in, os.O_RDONLY, 0)
	if err != nil {
		panic(err)
	}
	defer file.Close()

	if _, err := io.Copy(tw, file); err != nil {
		panic(err)
	}
}

What did you expect to see?

Generate a tar and compressed file.

What did you see instead?

panic: runtime error: cgo argument has Go pointer to Go pointer

goroutine 1 [running]:
github.com/DataDog/zstd.(*Writer).Write.func1(0xc000020080, 0xc00010cb80, 0xc00010cb80, 0x200, 0x200)
        /root/go/pkg/mod/github.com/!data!dog/zstd@v1.4.8/zstd_stream.go:181 +0xe5
github.com/DataDog/zstd.(*Writer).Write(0xc000020080, 0xc00010cb80, 0x200, 0x200, 0x1648, 0x0, 0x0)
        /root/go/pkg/mod/github.com/!data!dog/zstd@v1.4.8/zstd_stream.go:181 +0xf5
archive/tar.(*Writer).writeRawHeader(0xc00010ca80, 0xc00010cb80, 0x50aba0, 0x30, 0x0, 0x0)
        /usr/lib/go-1.15/src/archive/tar/writer.go:392 +0x7d
archive/tar.(*Writer).writeUSTARHeader(0xc00010ca80, 0xc00010caa8, 0xa, 0x0)
        /usr/lib/go-1.15/src/archive/tar/writer.go:125 +0x1be
archive/tar.(*Writer).WriteHeader(0xc00010ca80, 0xc00011a000, 0x59e34c, 0xa)
        /usr/lib/go-1.15/src/archive/tar/writer.go:97 +0x2e5
main.main()
        /root/test/main.go:34 +0x287

[Viq111]

Hi @keeword , thanks for the report.
We are tracking this in #97 and will fix asap.

Once it's merged (very likely this week), it should fix this issue