Ensure boltDB pathname is constructed uniformly

Keep the concatenation of the prefix and filename inside the boltdb
package, so we can't get it wrong outside.

db/boltdb.go

@@ -26,10 +26,15 @@ var (
 
 const (
 	NameIdent = "peername"
-	FileName  = "data.db"
+	fileName  = "data.db"
 )
 
-func NewBoltDB(dbPathname string) (*BoltDB, error) {
+func Pathname(dbPrefix string) string {
+	return dbPrefix + fileName
+}
+
+func NewBoltDB(dbPrefix string) (*BoltDB, error) {
+	dbPathname := Pathname(dbPrefix)
 	db, err := bolt.Open(dbPathname, 0660, nil)
 	if err != nil {
 		return nil, fmt.Errorf("[boltDB] Unable to open %s: %s", dbPathname, err)
@@ -38,8 +43,9 @@ func NewBoltDB(dbPathname string) (*BoltDB, error) {
 	return &BoltDB{db: db}, err
 }
 
-func NewBoltDBReadOnly(dbPathname string) (*BoltDB, error) {
+func NewBoltDBReadOnly(dbPrefix string) (*BoltDB, error) {
 	options := bolt.Options{Timeout: time.Millisecond * 50, ReadOnly: true}
+	dbPathname := Pathname(dbPrefix)
 	db, err := bolt.Open(dbPathname, 0660, &options)
 	if err != nil {
 		return nil, fmt.Errorf("[boltDB] Unable to open %s: %s", dbPathname, err)

net/uuid.go

@@ -36,8 +36,8 @@ func getSystemUUID(hostRoot string) ([]byte, error) {
 	return append(machineid, uuid...), nil
 }
 
-func getPersistedPeerName(pathName string) (mesh.PeerName, error) {
-	d, err := db.NewBoltDBReadOnly(pathName)
+func getPersistedPeerName(dbPrefix string) (mesh.PeerName, error) {
+	d, err := db.NewBoltDBReadOnly(dbPrefix)
 	if err != nil {
 		return mesh.UnknownPeerName, err
 	}
@@ -56,9 +56,8 @@ func getPersistedPeerName(pathName string) (mesh.PeerName, error) {
 func GetSystemPeerName(dbPrefix, hostRoot string) (string, error) {
 	// Check if we have a persisted name that matches the old-style ID for this host
 	if oldUUID, err := getOldStyleSystemUUID(); err == nil {
-		pathName := dbPrefix + db.FileName
-		if _, err := os.Stat(pathName); err == nil {
-			persistedPeerName, err := getPersistedPeerName(pathName)
+		if _, err := os.Stat(db.Pathname(dbPrefix)); err == nil {
+			persistedPeerName, err := getPersistedPeerName(dbPrefix)
 			if err != nil && !os.IsNotExist(err) {
 				return "", err
 			}

prog/weaver/main.go

@@ -260,7 +260,7 @@ func main() {
 		Log.Fatalf("--awsvpc mode is not compatible with the --password option")
 	}
 
-	db, err := db.NewBoltDB(dbPrefix + db.FileName)
+	db, err := db.NewBoltDB(dbPrefix)
 	checkFatal(err)
 	defer db.Close()