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-rw-r--r--vendor/github.com/pborman/uuid/node.go117
1 files changed, 117 insertions, 0 deletions
diff --git a/vendor/github.com/pborman/uuid/node.go b/vendor/github.com/pborman/uuid/node.go
new file mode 100644
index 00000000..42d60da8
--- /dev/null
+++ b/vendor/github.com/pborman/uuid/node.go
@@ -0,0 +1,117 @@
+// Copyright 2011 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 (
+ "net"
+ "sync"
+)
+
+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
+)
+
+// NodeInterface returns the name of the interface from which the NodeID was
+// derived. The interface "user" is returned if the NodeID was set by
+// SetNodeID.
+func NodeInterface() string {
+ defer nodeMu.Unlock()
+ nodeMu.Lock()
+ return ifname
+}
+
+// SetNodeInterface selects the hardware address to be used for Version 1 UUIDs.
+// If name is "" then the first usable interface found will be used or a random
+// Node ID will be generated. If a named interface cannot be found then false
+// is returned.
+//
+// SetNodeInterface never fails when name is "".
+func SetNodeInterface(name string) bool {
+ defer nodeMu.Unlock()
+ nodeMu.Lock()
+ return setNodeInterface(name)
+}
+
+func setNodeInterface(name string) bool {
+ if interfaces == nil {
+ var err error
+ interfaces, err = net.Interfaces()
+ if err != nil && name != "" {
+ return false
+ }
+ }
+
+ for _, ifs := range interfaces {
+ if len(ifs.HardwareAddr) >= 6 && (name == "" || name == ifs.Name) {
+ if setNodeID(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)
+ return true
+ }
+ return false
+}
+
+// NodeID returns a slice of a copy of the current Node ID, setting the Node ID
+// if not already set.
+func NodeID() []byte {
+ defer nodeMu.Unlock()
+ nodeMu.Lock()
+ if nodeID == nil {
+ setNodeInterface("")
+ }
+ nid := make([]byte, 6)
+ copy(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)
+ return true
+}
+
+// NodeID returns the 6 byte node id encoded in uuid. It returns nil if uuid is
+// not valid. The NodeID is only well defined for version 1 and 2 UUIDs.
+func (uuid UUID) NodeID() []byte {
+ if len(uuid) != 16 {
+ return nil
+ }
+ node := make([]byte, 6)
+ copy(node, uuid[10:])
+ return node
+}