141 lines
2.7 KiB
Go
141 lines
2.7 KiB
Go
package main
|
|
|
|
import (
|
|
"archive/tar"
|
|
"flag"
|
|
"io"
|
|
"io/fs"
|
|
"log"
|
|
"os"
|
|
"path/filepath"
|
|
"syscall"
|
|
"time"
|
|
"unsafe"
|
|
|
|
"golang.org/x/sys/unix"
|
|
)
|
|
|
|
// See https://github.com/benmcclelland/mtio
|
|
const (
|
|
MTIOCTOP = 0x40086d01 // Do magnetic tape operation
|
|
MTEOM = 12 // Goto end of recorded media (for appending files)
|
|
)
|
|
|
|
// Operation is struct for MTIOCTOP
|
|
type Operation struct {
|
|
Op int16 // Operation ID
|
|
Pad int16 // Padding to match C structures
|
|
Count int32 // Operation count
|
|
}
|
|
|
|
func main() {
|
|
file := flag.String("file", "/dev/nst0", "File (tape drive or tar file) to open")
|
|
dir := flag.String("dir", ".", "Directory to add to the file")
|
|
|
|
flag.Parse()
|
|
|
|
isRegular := true
|
|
stat, err := os.Stat(*file)
|
|
if err == nil {
|
|
isRegular = stat.Mode().IsRegular()
|
|
} else {
|
|
if os.IsNotExist(err) {
|
|
isRegular = true
|
|
} else {
|
|
panic(err)
|
|
}
|
|
}
|
|
|
|
var f *os.File
|
|
if isRegular {
|
|
f, err = os.OpenFile(*file, os.O_APPEND|os.O_WRONLY|os.O_CREATE, 0600)
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
|
|
// No need to go to end manually due to `os.O_APPEND`
|
|
} else {
|
|
// Go to end of file
|
|
syscall.Syscall(
|
|
syscall.SYS_IOCTL,
|
|
f.Fd(),
|
|
MTIOCTOP,
|
|
uintptr(unsafe.Pointer(
|
|
&Operation{
|
|
Op: MTEOM,
|
|
},
|
|
)),
|
|
)
|
|
|
|
f, err = os.OpenFile(*file, os.O_APPEND|os.O_WRONLY, os.ModeCharDevice)
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
}
|
|
defer f.Close()
|
|
|
|
tw := tar.NewWriter(f) // We are not closing the tar writer to prevent writing the trailer
|
|
|
|
if err := filepath.Walk(*dir, func(path string, info fs.FileInfo, err error) error {
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
link := ""
|
|
if info.Mode()&os.ModeSymlink == os.ModeSymlink {
|
|
if link, err = os.Readlink(path); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
hdr, err := tar.FileInfoHeader(info, link)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
hdr.Format = tar.FormatGNU // Required for AccessTime, ChangeTime etc.
|
|
|
|
var unixStat syscall.Stat_t
|
|
if err := syscall.Stat(path, &unixStat); err != nil {
|
|
return err
|
|
}
|
|
|
|
mtimesec, mtimensec := unixStat.Mtim.Unix()
|
|
atimesec, atimensec := unixStat.Atim.Unix()
|
|
ctimesec, ctimensec := unixStat.Ctim.Unix()
|
|
|
|
hdr.ModTime = time.Unix(mtimesec, mtimensec)
|
|
hdr.AccessTime = time.Unix(atimesec, atimensec)
|
|
hdr.ChangeTime = time.Unix(ctimesec, ctimensec)
|
|
|
|
hdr.Devmajor = int64(unix.Major(unixStat.Dev))
|
|
hdr.Devminor = int64(unix.Minor(unixStat.Dev))
|
|
|
|
hdr.Name = path
|
|
|
|
log.Println(hdr)
|
|
|
|
if err := tw.WriteHeader(hdr); err != nil {
|
|
return err
|
|
}
|
|
|
|
if !info.Mode().IsRegular() {
|
|
return nil
|
|
}
|
|
|
|
file, err := os.Open(path)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
defer file.Close()
|
|
|
|
if _, err := io.Copy(tw, file); err != nil {
|
|
return err
|
|
}
|
|
|
|
return nil
|
|
}); err != nil {
|
|
panic(err)
|
|
}
|
|
}
|