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Diffstat (limited to 'vendor/github.com/google/uuid/node.go')
-rw-r--r-- | vendor/github.com/google/uuid/node.go | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/vendor/github.com/google/uuid/node.go b/vendor/github.com/google/uuid/node.go new file mode 100644 index 000000000..d651a2b06 --- /dev/null +++ b/vendor/github.com/google/uuid/node.go @@ -0,0 +1,90 @@ +// 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 ( + "sync" +) + +var ( + nodeMu sync.Mutex + ifname string // name of interface being used + 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 +// 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 { + iname, addr := getHardwareInterface(name) // null implementation for js + if iname != "" && addr != nil { + ifname = iname + copy(nodeID[:], addr) + 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 == "" { + ifname = "random" + 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 == zeroID { + setNodeInterface("") + } + 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 { + if len(id) < 6 { + return false + } + defer nodeMu.Unlock() + nodeMu.Lock() + copy(nodeID[:], id) + ifname = "user" + 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 { + var node [6]byte + copy(node[:], uuid[10:]) + return node[:] +} |