chrootarchive: Add a const for tar options fd

Minor unrelated cleanup.

Signed-off-by: Colin Walters <walters@verbum.org>
This commit is contained in:
Colin Walters 2024-07-31 15:13:30 -04:00
parent d7679480f6
commit d5fab15c83
1 changed files with 5 additions and 1 deletions

View File

@ -30,6 +30,9 @@ func (dst *unpackDestination) Close() error {
return dst.root.Close() return dst.root.Close()
} }
// tarOptionsDescriptor is passed as an extra file
const tarOptionsDescriptor = 3
// rootFileDescriptor is passed as an extra file // rootFileDescriptor is passed as an extra file
const rootFileDescriptor = 4 const rootFileDescriptor = 4
@ -51,7 +54,7 @@ func untar() {
var options archive.TarOptions var options archive.TarOptions
// read the options from the pipe "ExtraFiles" // read the options from the pipe "ExtraFiles"
if err := json.NewDecoder(os.NewFile(3, "options")).Decode(&options); err != nil { if err := json.NewDecoder(os.NewFile(tarOptionsDescriptor, "options")).Decode(&options); err != nil {
fatal(err) fatal(err)
} }
@ -132,6 +135,7 @@ func invokeUnpack(decompressedArchive io.Reader, dest *unpackDestination, option
cmd := reexec.Command("storage-untar", dest.dest, procPathForFd(rootFileDescriptor)) cmd := reexec.Command("storage-untar", dest.dest, procPathForFd(rootFileDescriptor))
cmd.Stdin = decompressedArchive cmd.Stdin = decompressedArchive
// If you change this, change tarOptionsDescriptor above
cmd.ExtraFiles = append(cmd.ExtraFiles, r) // fd 3 cmd.ExtraFiles = append(cmd.ExtraFiles, r) // fd 3
// If you change this, change rootFileDescriptor above too // If you change this, change rootFileDescriptor above too
cmd.ExtraFiles = append(cmd.ExtraFiles, dest.root) // fd 4 cmd.ExtraFiles = append(cmd.ExtraFiles, dest.root) // fd 4