Vendor after merging mtrmac/image:docker-archive-auto-compression

Signed-off-by: Miloslav Trmač <mitr@redhat.com>

vendor/github.com/containers/storage/drivers/chown_unix.go

@@ -0,0 +1,55 @@
+// +build !windows
+
+package graphdriver
+
+import (
+	"fmt"
+	"os"
+	"syscall"
+
+	"github.com/containers/storage/pkg/idtools"
+)
+
+func platformLChown(path string, info os.FileInfo, toHost, toContainer *idtools.IDMappings) error {
+	sysinfo := info.Sys()
+	if st, ok := sysinfo.(*syscall.Stat_t); ok {
+		// Map an on-disk UID/GID pair from host to container
+		// using the first map, then back to the host using the
+		// second map.  Skip that first step if they're 0, to
+		// compensate for cases where a parent layer should
+		// have had a mapped value, but didn't.
+		uid, gid := int(st.Uid), int(st.Gid)
+		if toContainer != nil {
+			pair := idtools.IDPair{
+				UID: uid,
+				GID: gid,
+			}
+			mappedUid, mappedGid, err := toContainer.ToContainer(pair)
+			if err != nil {
+				if (uid != 0) || (gid != 0) {
+					return fmt.Errorf("error mapping host ID pair %#v for %q to container: %v", pair, path, err)
+				}
+				mappedUid, mappedGid = uid, gid
+			}
+			uid, gid = mappedUid, mappedGid
+		}
+		if toHost != nil {
+			pair := idtools.IDPair{
+				UID: uid,
+				GID: gid,
+			}
+			mappedPair, err := toHost.ToHost(pair)
+			if err != nil {
+				return fmt.Errorf("error mapping container ID pair %#v for %q to host: %v", pair, path, err)
+			}
+			uid, gid = mappedPair.UID, mappedPair.GID
+		}
+		if uid != int(st.Uid) || gid != int(st.Gid) {
+			// Make the change.
+			if err := syscall.Lchown(path, uid, gid); err != nil {
+				return fmt.Errorf("%s: chown(%q): %v", os.Args[0], path, err)
+			}
+		}
+	}
+	return nil
+}