moby/pkg/system/chtimes.go
Stefan J. Wernli 041a9510c6 Fixing 'docker save' on Windows.
Save was failing file integrity checksums due to bugs in both
Windows and Docker. This commit includes fixes to file time handling
in tarexport and system.chtimes that are necessary along with
the Windows platform fixes to correctly support save. With this
change, sysfile_backups for windowsfilter driver are no longer
needed, so that code is removed.

Signed-off-by: Stefan J. Wernli <swernli@microsoft.com>
2016-02-08 18:08:49 -08:00

52 lines
1.1 KiB
Go

package system
import (
"os"
"syscall"
"time"
"unsafe"
)
var (
maxTime time.Time
)
func init() {
if unsafe.Sizeof(syscall.Timespec{}.Nsec) == 8 {
// This is a 64 bit timespec
// os.Chtimes limits time to the following
maxTime = time.Unix(0, 1<<63-1)
} else {
// This is a 32 bit timespec
maxTime = time.Unix(1<<31-1, 0)
}
}
// Chtimes changes the access time and modified time of a file at the given path
func Chtimes(name string, atime time.Time, mtime time.Time) error {
unixMinTime := time.Unix(0, 0)
unixMaxTime := maxTime
// If the modified time is prior to the Unix Epoch, or after the
// end of Unix Time, os.Chtimes has undefined behavior
// default to Unix Epoch in this case, just in case
if atime.Before(unixMinTime) || atime.After(unixMaxTime) {
atime = unixMinTime
}
if mtime.Before(unixMinTime) || mtime.After(unixMaxTime) {
mtime = unixMinTime
}
if err := os.Chtimes(name, atime, mtime); err != nil {
return err
}
// Take platform specific action for setting create time.
if err := setCTime(name, mtime); err != nil {
return err
}
return nil
}