1 files changed, 140 insertions, 0 deletions
diff --git a/vendor/github.com/twinj/uuid/saver.go b/vendor/github.com/twinj/uuid/saver.go
new file mode 100644
index 0000000000..0b776a46a9
--- /dev/null
+++ b/vendor/github.com/twinj/uuid/saver.go
@@ -0,0 +1,140 @@
+package uuid
+
+/****************
+ * Date: 21/06/15
+ * Time: 5:48 PM
+ ***************/
+
+import (
+	"encoding/gob"
+	"log"
+	"os"
+	"time"
+)
+
+func init() {
+	gob.Register(stateEntity{})
+}
+
+func SetupFileSystemStateSaver(pConfig StateSaverConfig) {
+	saver := &FileSystemSaver{}
+	saver.saveReport = pConfig.SaveReport
+	saver.saveSchedule = int64(pConfig.SaveSchedule)
+	SetupCustomStateSaver(saver)
+}
+
+// A wrapper for default setup of the FileSystemStateSaver
+type StateSaverConfig struct {
+
+	// Print save log
+	SaveReport bool
+
+	// Save every x nanoseconds
+	SaveSchedule time.Duration
+}
+
+// ***********************************************  StateEntity
+
+// StateEntity acts as a marshaller struct for the state
+type stateEntity struct {
+	Past     Timestamp
+	Node     []byte
+	Sequence uint16
+}
+
+// This implements the StateSaver interface for UUIDs
+type FileSystemSaver struct {
+	cache        *os.File
+	saveState    uint64
+	saveReport   bool
+	saveSchedule int64
+}
+
+// Saves the current state of the generator
+// If the scheduled file save is reached then the file is synced
+func (o *FileSystemSaver) Save(pState *State) {
+	if pState.past >= pState.next {
+		err := o.open()
+		defer o.cache.Close()
+		if err != nil {
+			log.Println("uuid.State.save:", err)
+			return
+		}
+		// do the save
+		o.encode(pState)
+		// a tick is 100 nano seconds
+		pState.next = pState.past + Timestamp(o.saveSchedule / 100)
+		if o.saveReport {
+			log.Printf("UUID STATE: SAVED %d", pState.past)
+		}
+	}
+}
+
+func (o *FileSystemSaver) Init(pState *State) {
+	pState.saver = o
+	err := o.open()
+	defer o.cache.Close()
+	if err != nil {
+		if os.IsNotExist(err) {
+			log.Printf("'%s' created\n", "uuid.SaveState")
+			var err error
+			o.cache, err = os.Create(os.TempDir() + "/state.unique")
+			if err != nil {
+				log.Println("uuid.State.init: SaveState error:", err)
+				goto pastInit
+			}
+			o.encode(pState)
+		} else {
+			log.Println("uuid.State.init: SaveState error:", err)
+			goto pastInit
+		}
+	}
+	err = o.decode(pState)
+	if err != nil {
+		goto pastInit
+	}
+	pState.randomSequence = false
+pastInit:
+	if timestamp() <= pState.past {
+		pState.sequence++
+	}
+	pState.next = pState.past
+}
+
+func (o *FileSystemSaver) reset() {
+	o.cache.Seek(0, 0)
+}
+
+func (o *FileSystemSaver) open() error {
+	var err error
+	o.cache, err = os.OpenFile(os.TempDir()+"/state.unique", os.O_RDWR, os.ModeExclusive)
+	return err
+}
+
+// Encodes State generator data into a saved file
+func (o *FileSystemSaver) encode(pState *State) {
+	// ensure reader state is ready for use
+	o.reset()
+	enc := gob.NewEncoder(o.cache)
+	// Wrap private State data into the StateEntity
+	err := enc.Encode(&stateEntity{pState.past, pState.node, pState.sequence})
+	if err != nil {
+		log.Panic("UUID.encode error:", err)
+	}
+}
+
+// Decodes StateEntity data into the main State
+func (o *FileSystemSaver) decode(pState *State) error {
+	o.reset()
+	dec := gob.NewDecoder(o.cache)
+	entity := stateEntity{}
+	err := dec.Decode(&entity)
+	if err != nil {
+		log.Println("uuid.decode error:", err)
+		return err
+	}
+	pState.past = entity.Past
+	pState.node = entity.Node
+	pState.sequence = entity.Sequence
+	return nil
+}