Handle CORS requests (#6289)

vendor/golang.org/x/sys/unix/syscall_darwin.go

@@ -144,6 +144,23 @@ func getAttrList(path string, attrList attrList, attrBuf []byte, options uint) (
 
 //sys getattrlist(path *byte, list unsafe.Pointer, buf unsafe.Pointer, size uintptr, options int) (err error)
 
+func SysctlClockinfo(name string) (*Clockinfo, error) {
+	mib, err := sysctlmib(name)
+	if err != nil {
+		return nil, err
+	}
+
+	n := uintptr(SizeofClockinfo)
+	var ci Clockinfo
+	if err := sysctl(mib, (*byte)(unsafe.Pointer(&ci)), &n, nil, 0); err != nil {
+		return nil, err
+	}
+	if n != SizeofClockinfo {
+		return nil, EIO
+	}
+	return &ci, nil
+}
+
 //sysnb pipe() (r int, w int, err error)
 
 func Pipe(p []int) (err error) {