1 files changed, 137 insertions, 0 deletions
diff --git a/vendor/github.com/twinj/uuid/state.go b/vendor/github.com/twinj/uuid/state.go
new file mode 100644
index 0000000000..f3920776cd
--- /dev/null
+++ b/vendor/github.com/twinj/uuid/state.go
@@ -0,0 +1,137 @@
+package uuid
+
+/****************
+ * Date: 14/02/14
+ * Time: 7:43 PM
+ ***************/
+
+import (
+	"bytes"
+	"log"
+	seed "math/rand"
+	"net"
+	"sync"
+)
+
+
+// **************************************************** State
+
+func SetupCustomStateSaver(pSaver StateSaver) {
+	state.Lock()
+	pSaver.Init(&state)
+	state.init()
+	state.Unlock()
+}
+
+// Holds package information about the current
+// state of the UUID generator
+type State struct {
+
+	// A flag which informs whether to
+	// randomly create a node id
+	randomNode bool
+
+	// A flag which informs whether to
+	// randomly create the sequence
+	randomSequence bool
+
+	// the last time UUID was saved
+	past Timestamp
+
+	// the next time the state will be saved
+	next Timestamp
+
+	// the last node which saved a UUID
+	node []byte
+
+	// An iterated value to help ensure different
+	// values across the same domain
+	sequence uint16
+
+	sync.Mutex
+
+	// save state interface
+	saver StateSaver
+}
+
+// Changes the state with current data
+// Compares the current found node to the last node stored,
+// If they are the same or randomSequence is already set due
+// to an earlier read issue then the sequence is randomly generated
+// else if there is an issue with the time the sequence is incremented
+func (o *State) read(pNow Timestamp, pNode net.HardwareAddr) {
+	if bytes.Equal([]byte(pNode), o.node) || o.randomSequence {
+		o.sequence = uint16(seed.Int()) & 0x3FFF
+	} else if pNow < o.past {
+		o.sequence++
+	}
+	o.past = pNow
+	o.node = pNode
+}
+
+func (o *State) persist() {
+	if o.saver != nil {
+		o.saver.Save(o)
+	}
+}
+
+// Initialises the UUID state when the package is first loaded
+// it first attempts to decode the file state into State
+// if this file does not exist it will create the file and do a flush
+// of the random state which gets loaded at package runtime
+// second it will attempt to resolve the current hardware address nodeId
+// thirdly it will check the state of the clock
+func (o *State) init() {
+	if o.saver != nil {
+		intfcs, err := net.Interfaces()
+		if err != nil {
+			log.Println("uuid.State.init: address error: will generate random node id instead", err)
+			return
+		}
+		a := getHardwareAddress(intfcs)
+		if a == nil {
+			log.Println("uuid.State.init: address error: will generate random node id instead", err)
+			return
+		}
+		// Don't use random as we have a real address
+		o.randomSequence = false
+		if bytes.Equal([]byte(a), state.node) {
+			state.sequence++
+		}
+		state.node = a
+		state.randomNode = false
+	}
+}
+
+func getHardwareAddress(pInterfaces []net.Interface) net.HardwareAddr {
+	for _, inter := range pInterfaces {
+		// Initially I could multicast out the Flags to get
+		// whether the interface was up but started failing
+		if (inter.Flags & (1 << net.FlagUp)) != 0 {
+			//if inter.Flags.String() != "0" {
+			if addrs, err := inter.Addrs(); err == nil {
+				for _, addr := range addrs {
+					if addr.String() != "0.0.0.0" && !bytes.Equal([]byte(inter.HardwareAddr), make([]byte, len(inter.HardwareAddr))) {
+						return inter.HardwareAddr
+					}
+				}
+			}
+		}
+	}
+	return nil
+}
+
+// *********************************************** StateSaver interface
+
+// Use this interface to setup a custom state saver if you wish to have
+// v1 UUIDs based on your node id and constant time.
+type StateSaver interface {
+	// Init is run if Setup() is false
+	// Init should setup the system to save the state
+	Init(*State)
+
+	// Save saves the state and is called only if const V1Save and
+	// Setup() is true
+	Save(*State)
+}
+