github.com/karalabe/go-ethereum@v0.8.5/Godeps/_workspace/src/code.google.com/p/go-uuid/uuid/dce.go (about)

     1  // Copyright 2011 Google Inc.  All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  package uuid
     6  
     7  import (
     8  	"encoding/binary"
     9  	"fmt"
    10  	"os"
    11  )
    12  
    13  // A Domain represents a Version 2 domain
    14  type Domain byte
    15  
    16  // Domain constants for DCE Security (Version 2) UUIDs.
    17  const (
    18  	Person = Domain(0)
    19  	Group  = Domain(1)
    20  	Org    = Domain(2)
    21  )
    22  
    23  // NewDCESecurity returns a DCE Security (Version 2) UUID.
    24  //
    25  // The domain should be one of Person, Group or Org.
    26  // On a POSIX system the id should be the users UID for the Person
    27  // domain and the users GID for the Group.  The meaning of id for
    28  // the domain Org or on non-POSIX systems is site defined.
    29  //
    30  // For a given domain/id pair the same token may be returned for up to
    31  // 7 minutes and 10 seconds.
    32  func NewDCESecurity(domain Domain, id uint32) UUID {
    33  	uuid := NewUUID()
    34  	if uuid != nil {
    35  		uuid[6] = (uuid[6] & 0x0f) | 0x20 // Version 2
    36  		uuid[9] = byte(domain)
    37  		binary.BigEndian.PutUint32(uuid[0:], id)
    38  	}
    39  	return uuid
    40  }
    41  
    42  // NewDCEPerson returns a DCE Security (Version 2) UUID in the person
    43  // domain with the id returned by os.Getuid.
    44  //
    45  //  NewDCEPerson(Person, uint32(os.Getuid()))
    46  func NewDCEPerson() UUID {
    47  	return NewDCESecurity(Person, uint32(os.Getuid()))
    48  }
    49  
    50  // NewDCEGroup returns a DCE Security (Version 2) UUID in the group
    51  // domain with the id returned by os.Getgid.
    52  //
    53  //  NewDCEGroup(Group, uint32(os.Getgid()))
    54  func NewDCEGroup() UUID {
    55  	return NewDCESecurity(Group, uint32(os.Getgid()))
    56  }
    57  
    58  // Domain returns the domain for a Version 2 UUID or false.
    59  func (uuid UUID) Domain() (Domain, bool) {
    60  	if v, _ := uuid.Version(); v != 2 {
    61  		return 0, false
    62  	}
    63  	return Domain(uuid[9]), true
    64  }
    65  
    66  // Id returns the id for a Version 2 UUID or false.
    67  func (uuid UUID) Id() (uint32, bool) {
    68  	if v, _ := uuid.Version(); v != 2 {
    69  		return 0, false
    70  	}
    71  	return binary.BigEndian.Uint32(uuid[0:4]), true
    72  }
    73  
    74  func (d Domain) String() string {
    75  	switch d {
    76  	case Person:
    77  		return "Person"
    78  	case Group:
    79  		return "Group"
    80  	case Org:
    81  		return "Org"
    82  	}
    83  	return fmt.Sprintf("Domain%d", int(d))
    84  }