Change a UUID from []byte to [16]byte along with other API changes.

Author: bormanp

CONTRIBUTING.md

@@ -0,0 +1,10 @@
+# How to contribute
+
+We definitely welcome patches and contribution to this project!
+
+### Legal requirements
+
+In order to protect both you and ourselves, you will need to sign the
+[Contributor License Agreement](https://cla.developers.google.com/clas).
+
+You may have already signed it for other Google projects.

CONTRIBUTORS

@@ -1 +1,9 @@
 Paul Borman <borman@google.com>
+bmatsuo
+shawnps
+theory
+jboverfelt
+dsymonds
+cd1
+wallclockbuilder
+dansouza

README.md

@@ -3,6 +3,11 @@ This project was automatically exported from code.google.com/p/go-uuid
 # uuid ![build status](https://travis-ci.org/google/uuid.svg?branch=master)
 The uuid package generates and inspects UUIDs based on [RFC 412](http://tools.ietf.org/html/rfc4122) and DCE 1.1: Authentication and Security Services. 
 
+This package is based on the github.com/pborman/uuid package (previously named
+code.google.com/p/go-uuid).  It differs from these earlier packages in that
+a UUID is a 16 byte array rather than a byte slice.  One loss due to this
+change is the ability to represent an invalid UUID (vs a NIL UUID).
+
 ###### Install
 `go get github.com/google/uuid`
 

dce.go

@@ -1,4 +1,4 @@
-// Copyright 2011 Google Inc.  All rights reserved.
+// Copyright 2016 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.
 
@@ -29,46 +29,42 @@ const (
 //
 // 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 {
+func NewDCESecurity(domain Domain, id uint32) (UUID, error) {
+	uuid, err := NewUUID()
+	if err == nil {
 		uuid[6] = (uuid[6] & 0x0f) | 0x20 // Version 2
 		uuid[9] = byte(domain)
 		binary.BigEndian.PutUint32(uuid[0:], id)
 	}
-	return uuid
+	return uuid, err
 }
 
 // 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 {
+func NewDCEPerson() (UUID, error) {
 	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 {
+func NewDCEGroup() (UUID, error) {
 	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
+// Domain returns the domain for a Version 2 UUID.  Domains are only defined
+// for Version 2 UUIDs.
+func (uuid UUID) Domain() Domain {
+	return Domain(uuid[9])
 }
 
-// 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
+// Id returns the id for a Version 2 UUID. Ids are only defined for Vrsion 2
+// UUIDs.
+func (uuid UUID) Id() uint32 {
+	return binary.BigEndian.Uint32(uuid[0:4])
 }
 
 func (d Domain) String() string {

doc.go

@@ -1,8 +1,12 @@
-// Copyright 2011 Google Inc.  All rights reserved.
+// Copyright 2016 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.
 
-// The uuid package generates and inspects UUIDs.
+// Package uuid generates and inspects UUIDs.
 //
-// UUIDs are based on RFC 4122 and DCE 1.1: Authentication and Security Services.
+// UUIDs are based on RFC 4122 and DCE 1.1: Authentication and Security
+// Services.
+//
+// A UUID is a 16 byte (128 bit) array.  UUIDs may be used as keys to
+// maps or compared directly.
 package uuid

hash.go

@@ -1,4 +1,4 @@
-// Copyright 2011 Google Inc.  All rights reserved.
+// Copyright 2016 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.
 
@@ -10,13 +10,13 @@ import (
 	"hash"
 )
 
-// Well known Name Space IDs and UUIDs
+// Well known namespace IDs and UUIDs
 var (
-	NameSpace_DNS  = Parse("6ba7b810-9dad-11d1-80b4-00c04fd430c8")
-	NameSpace_URL  = Parse("6ba7b811-9dad-11d1-80b4-00c04fd430c8")
-	NameSpace_OID  = Parse("6ba7b812-9dad-11d1-80b4-00c04fd430c8")
-	NameSpace_X500 = Parse("6ba7b814-9dad-11d1-80b4-00c04fd430c8")
-	NIL            = Parse("00000000-0000-0000-0000-000000000000")
+	NameSpace_DNS  = MustParse("6ba7b810-9dad-11d1-80b4-00c04fd430c8")
+	NameSpace_URL  = MustParse("6ba7b811-9dad-11d1-80b4-00c04fd430c8")
+	NameSpace_OID  = MustParse("6ba7b812-9dad-11d1-80b4-00c04fd430c8")
+	NameSpace_X500 = MustParse("6ba7b814-9dad-11d1-80b4-00c04fd430c8")
+	NIL            UUID // empty UUID, all zeros
 )
 
 // NewHash returns a new UUID derived from the hash of space concatenated with
@@ -26,26 +26,26 @@ var (
 // NewMD5 and NewSHA1.
 func NewHash(h hash.Hash, space UUID, data []byte, version int) UUID {
 	h.Reset()
-	h.Write(space)
+	h.Write(space[:])
 	h.Write([]byte(data))
 	s := h.Sum(nil)
-	uuid := make([]byte, 16)
-	copy(uuid, s)
+	var uuid UUID
+	copy(uuid[:], s)
 	uuid[6] = (uuid[6] & 0x0f) | uint8((version&0xf)<<4)
 	uuid[8] = (uuid[8] & 0x3f) | 0x80 // RFC 4122 variant
 	return uuid
 }
 
 // NewMD5 returns a new MD5 (Version 3) UUID based on the
-// supplied name space and data.
+// supplied name space and data.  It is the same as calling:
 //
 //  NewHash(md5.New(), space, data, 3)
 func NewMD5(space UUID, data []byte) UUID {
 	return NewHash(md5.New(), space, data, 3)
 }
 
 // NewSHA1 returns a new SHA1 (Version 5) UUID based on the
-// supplied name space and data.
+// supplied name space and data.  It is the same as calling:
 //
 //  NewHash(sha1.New(), space, data, 5)
 func NewSHA1(space UUID, data []byte) UUID {

json_test.go

@@ -1,4 +1,4 @@
-// Copyright 2014 Google Inc.  All rights reserved.
+// Copyright 2016 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.
 
@@ -10,7 +10,7 @@ import (
 	"testing"
 )
 
-var testUUID = Parse("f47ac10b-58cc-0372-8567-0e02b2c3d479")
+var testUUID = MustParse("f47ac10b-58cc-0372-8567-0e02b2c3d479")
 
 func TestJSON(t *testing.T) {
 	type S struct {
@@ -35,9 +35,10 @@ func BenchmarkUUID_MarshalJSON(b *testing.B) {
 	x := &struct {
 		UUID UUID `json:"uuid"`
 	}{}
-	x.UUID = Parse("f47ac10b-58cc-0372-8567-0e02b2c3d479")
-	if x.UUID == nil {
-		b.Fatal("invalid uuid")
+	var err error
+	x.UUID, err = Parse("f47ac10b-58cc-0372-8567-0e02b2c3d479")
+	if err != nil {
+		b.Fatal(err)
 	}
 	for i := 0; i < b.N; i++ {
 		js, err := json.Marshal(x)

marshal.go

@@ -0,0 +1,42 @@
+// Copyright 2016 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 (
+	"fmt"
+	"unsafe"
+)
+
+// MarshalText implements encoding.TextMarshaler.
+func (u UUID) MarshalText() ([]byte, error) {
+	var js [36]byte
+	encodeHex(js[:], u)
+	return js[:], nil
+}
+
+// UnmarshalText implements encoding.TextUnmarshaler.
+func (u *UUID) UnmarshalText(data []byte) error {
+	// See comment in ParseBytes why we do this.
+	// id, err := ParseBytes(data)
+        id, err := Parse(*(*string)(unsafe.Pointer(&data)))
+	if err == nil {
+		*u = id
+	}
+	return err
+}
+
+// MarshalBinary implements encoding.BinaryMarshaler.
+func (u UUID) MarshalBinary() ([]byte, error) {
+	return u[:], nil
+}
+
+// UnmarshalBinary implements encoding.BinaryUnmarshaler.
+func (u *UUID) UnmarshalBinary(data []byte) error {
+	if len(data) != 16 {
+		return fmt.Errorf("invalid UUID (got %d bytes)", len(data))
+	}
+	copy(u[:], data)
+	return nil
+}

node.go

@@ -1,4 +1,4 @@
-// Copyright 2011 Google Inc.  All rights reserved.
+// Copyright 2016 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.
 
@@ -13,7 +13,8 @@ var (
 	nodeMu     sync.Mutex
 	interfaces []net.Interface // cached list of interfaces
 	ifname     string          // name of interface being used
-	nodeID     []byte          // hardware for version 1 UUIDs
+	nodeID     [6]byte         // hardware for version 1 UUIDs
+	zeroID     [6]byte         // nodeID with only 0's
 )
 
 // NodeInterface returns the name of the interface from which the NodeID was
@@ -48,21 +49,17 @@ func setNodeInterface(name string) bool {
 
 	for _, ifs := range interfaces {
 		if len(ifs.HardwareAddr) >= 6 && (name == "" || name == ifs.Name) {
-			if setNodeID(ifs.HardwareAddr) {
-				ifname = ifs.Name
-				return true
-			}
+			copy(nodeID[:], ifs.HardwareAddr)
+			ifname = ifs.Name
+			return true
 		}
 	}
 
 	// We found no interfaces with a valid hardware address.  If name
 	// does not specify a specific interface generate a random Node ID
 	// (section 4.1.6)
 	if name == "" {
-		if nodeID == nil {
-			nodeID = make([]byte, 6)
-		}
-		randomBits(nodeID)
+		randomBits(nodeID[:])
 		return true
 	}
 	return false
@@ -73,35 +70,24 @@ func setNodeInterface(name string) bool {
 func NodeID() []byte {
 	defer nodeMu.Unlock()
 	nodeMu.Lock()
-	if nodeID == nil {
+	if nodeID == zeroID {
 		setNodeInterface("")
 	}
-	nid := make([]byte, 6)
-	copy(nid, nodeID)
-	return nid
+	nid := nodeID
+	return nid[:]
 }
 
 // SetNodeID sets the Node ID to be used for Version 1 UUIDs.  The first 6 bytes
 // of id are used.  If id is less than 6 bytes then false is returned and the
 // Node ID is not set.
 func SetNodeID(id []byte) bool {
-	defer nodeMu.Unlock()
-	nodeMu.Lock()
-	if setNodeID(id) {
-		ifname = "user"
-		return true
-	}
-	return false
-}
-
-func setNodeID(id []byte) bool {
 	if len(id) < 6 {
 		return false
 	}
-	if nodeID == nil {
-		nodeID = make([]byte, 6)
-	}
-	copy(nodeID, id)
+	defer nodeMu.Unlock()
+	nodeMu.Lock()
+	copy(nodeID[:], id)
+	ifname = "user"
 	return true
 }
 
@@ -111,7 +97,7 @@ func (uuid UUID) NodeID() []byte {
 	if len(uuid) != 16 {
 		return nil
 	}
-	node := make([]byte, 6)
-	copy(node, uuid[10:])
-	return node
+	var node [6]byte
+	copy(node[:], uuid[10:])
+	return node[:]
 }

seq_test.go

@@ -1,4 +1,4 @@
-// Copyright 2014 Google Inc.  All rights reserved.
+// Copyright 2016 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.
 
@@ -42,7 +42,7 @@ func TestClockSeqRace(t *testing.T) {
 				select {
 				case <-done:
 					return
-				case ch <- NewUUID():
+				case ch <- MustNewUUID():
 				}
 			}
 		}()