vendor: github.com/moby/go-archive v0.1.0

full diff: https://github.com/moby/go-archive/compare/21f3f3385ab7...v0.1.0

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
This commit is contained in:
Sebastiaan van Stijn
2025-04-16 13:47:10 +02:00
parent 8c74109330
commit d75c650792
19 changed files with 559 additions and 458 deletions

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package tarheader
import (
"archive/tar"
"os"
)
// assert that we implement [tar.FileInfoNames].
var _ tar.FileInfoNames = (*nosysFileInfo)(nil)
// nosysFileInfo hides the system-dependent info of the wrapped FileInfo to
// prevent tar.FileInfoHeader from introspecting it and potentially calling into
// glibc.
//
// It implements [tar.FileInfoNames] to further prevent [tar.FileInfoHeader]
// from performing any lookups on go1.23 and up. see https://go.dev/issue/50102
type nosysFileInfo struct {
os.FileInfo
}
// Uname stubs out looking up username. It implements [tar.FileInfoNames]
// to prevent [tar.FileInfoHeader] from loading libraries to perform
// username lookups.
func (fi nosysFileInfo) Uname() (string, error) {
return "", nil
}
// Gname stubs out looking up group-name. It implements [tar.FileInfoNames]
// to prevent [tar.FileInfoHeader] from loading libraries to perform
// username lookups.
func (fi nosysFileInfo) Gname() (string, error) {
return "", nil
}
func (fi nosysFileInfo) Sys() interface{} {
// A Sys value of type *tar.Header is safe as it is system-independent.
// The tar.FileInfoHeader function copies the fields into the returned
// header without performing any OS lookups.
if sys, ok := fi.FileInfo.Sys().(*tar.Header); ok {
return sys
}
return nil
}
// FileInfoHeaderNoLookups creates a partially-populated tar.Header from fi.
//
// Compared to the archive/tar.FileInfoHeader function, this function is safe to
// call from a chrooted process as it does not populate fields which would
// require operating system lookups. It behaves identically to
// tar.FileInfoHeader when fi is a FileInfo value returned from
// tar.Header.FileInfo().
//
// When fi is a FileInfo for a native file, such as returned from os.Stat() and
// os.Lstat(), the returned Header value differs from one returned from
// tar.FileInfoHeader in the following ways. The Uname and Gname fields are not
// set as OS lookups would be required to populate them. The AccessTime and
// ChangeTime fields are not currently set (not yet implemented) although that
// is subject to change. Callers which require the AccessTime or ChangeTime
// fields to be zeroed should explicitly zero them out in the returned Header
// value to avoid any compatibility issues in the future.
func FileInfoHeaderNoLookups(fi os.FileInfo, link string) (*tar.Header, error) {
hdr, err := tar.FileInfoHeader(nosysFileInfo{fi}, link)
if err != nil {
return nil, err
}
return hdr, sysStat(fi, hdr)
}

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//go:build !windows
package tarheader
import (
"archive/tar"
"os"
"runtime"
"syscall"
"golang.org/x/sys/unix"
)
// sysStat populates hdr from system-dependent fields of fi without performing
// any OS lookups.
func sysStat(fi os.FileInfo, hdr *tar.Header) error {
// Devmajor and Devminor are only needed for special devices.
// In FreeBSD, RDev for regular files is -1 (unless overridden by FS):
// https://cgit.freebsd.org/src/tree/sys/kern/vfs_default.c?h=stable/13#n1531
// (NODEV is -1: https://cgit.freebsd.org/src/tree/sys/sys/param.h?h=stable/13#n241).
// ZFS in particular does not override the default:
// https://cgit.freebsd.org/src/tree/sys/contrib/openzfs/module/os/freebsd/zfs/zfs_vnops_os.c?h=stable/13#n2027
// Since `Stat_t.Rdev` is uint64, the cast turns -1 into (2^64 - 1).
// Such large values cannot be encoded in a tar header.
if runtime.GOOS == "freebsd" && hdr.Typeflag != tar.TypeBlock && hdr.Typeflag != tar.TypeChar {
return nil
}
s, ok := fi.Sys().(*syscall.Stat_t)
if !ok {
return nil
}
hdr.Uid = int(s.Uid)
hdr.Gid = int(s.Gid)
if s.Mode&unix.S_IFBLK != 0 ||
s.Mode&unix.S_IFCHR != 0 {
hdr.Devmajor = int64(unix.Major(uint64(s.Rdev))) //nolint: unconvert
hdr.Devminor = int64(unix.Minor(uint64(s.Rdev))) //nolint: unconvert
}
return nil
}

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package tarheader
import (
"archive/tar"
"os"
)
// sysStat populates hdr from system-dependent fields of fi without performing
// any OS lookups. It is a no-op on Windows.
func sysStat(os.FileInfo, *tar.Header) error {
return nil
}