path: root/vendor/github.com/pborman/uuid/dce.go

// Copyright 2011 Google Inc.  All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package uuid

import (
    "encoding/binary"
    "fmt"
    "os"
)

// A Domain represents a Version 2 domain
type Domain byte

// Domain constants for DCE Security (Version 2) UUIDs.
const (
    Person = Domain(0)
    Group  = Domain(1)
    Org    = Domain(2)
)

// NewDCESecurity returns a DCE Security (Version 2) UUID.
//
// The domain should be one of Person, Group or Org.
// On a POSIX system the id should be the users UID for the Person
// domain and the users GID for the Group.  The meaning of id for
// the domain Org or on non-POSIX systems is site defined.
//
// For a given domain/id pair the same token may be returned for up to
// 7 minutes and 10 seconds.
func NewDCESecurity(domain Domain, id uint32) UUID {
    uuid := NewUUID()
    if uuid != nil {
        uuid[6] = (uuid[6] & 0x0f) | 0x20 // Version 2
        uuid[9] = byte(domain)
        binary.BigEndian.PutUint32(uuid[0:], id)
    }
    return uuid
}

// NewDCEPerson returns a DCE Security (Version 2) UUID in the person
// domain with the id returned by os.Getuid.
//
//  NewDCEPerson(Person, uint32(os.Getuid()))
func NewDCEPerson() UUID {
    return NewDCESecurity(Person, uint32(os.Getuid()))
}

// NewDCEGroup returns a DCE Security (Version 2) UUID in the group
// domain with the id returned by os.Getgid.
//
//  NewDCEGroup(Group, uint32(os.Getgid()))
func NewDCEGroup() UUID {
    return NewDCESecurity(Group, uint32(os.Getgid()))
}

// Domain returns the domain for a Version 2 UUID or false.
func (uuid UUID) Domain() (Domain, bool) {
    if v, _ := uuid.Version(); v != 2 {
        return 0, false
    }
    return Domain(uuid[9]), true
}

// Id returns the id for a Version 2 UUID or false.
func (uuid UUID) Id() (uint32, bool) {
    if v, _ := uuid.Version(); v != 2 {
        return 0, false
    }
    return binary.BigEndian.Uint32(uuid[0:4]), true
}

func (d Domain) String() string {
    switch d {
    case Person:
        return "Person"
    case Group:
        return "Group"
    case Org:
        return "Org"
    }
    return fmt.Sprintf("Domain%d", int(d))
}