ducky/devices
2015-11-27
Parent:b6494e1a499e
ducky/devices/vendor/code.google.com/p/go-uuid/uuid/node.go
Implement and test updating devices, and reuse contexts. Update all our tests to use the same context.Context instance within each test case, so static analysis about how we're passing contexts around dosn't get tripped up. Also, write a test that will check to make sure that our Storer implementations all actually update the Device correctly. We create every possible permutation of a DeviceChange, just to make sure they all work.
| paddy@0 | 1 // Copyright 2011 Google Inc. All rights reserved. |
| paddy@0 | 2 // Use of this source code is governed by a BSD-style |
| paddy@0 | 3 // license that can be found in the LICENSE file. |
| paddy@0 | 4 |
| paddy@0 | 5 package uuid |
| paddy@0 | 6 |
| paddy@0 | 7 import "net" |
| paddy@0 | 8 |
| paddy@0 | 9 var ( |
| paddy@0 | 10 interfaces []net.Interface // cached list of interfaces |
| paddy@0 | 11 ifname string // name of interface being used |
| paddy@0 | 12 nodeID []byte // hardware for version 1 UUIDs |
| paddy@0 | 13 ) |
| paddy@0 | 14 |
| paddy@0 | 15 // NodeInterface returns the name of the interface from which the NodeID was |
| paddy@0 | 16 // derived. The interface "user" is returned if the NodeID was set by |
| paddy@0 | 17 // SetNodeID. |
| paddy@0 | 18 func NodeInterface() string { |
| paddy@0 | 19 return ifname |
| paddy@0 | 20 } |
| paddy@0 | 21 |
| paddy@0 | 22 // SetNodeInterface selects the hardware address to be used for Version 1 UUIDs. |
| paddy@0 | 23 // If name is "" then the first usable interface found will be used or a random |
| paddy@0 | 24 // Node ID will be generated. If a named interface cannot be found then false |
| paddy@0 | 25 // is returned. |
| paddy@0 | 26 // |
| paddy@0 | 27 // SetNodeInterface never fails when name is "". |
| paddy@0 | 28 func SetNodeInterface(name string) bool { |
| paddy@0 | 29 if interfaces == nil { |
| paddy@0 | 30 var err error |
| paddy@0 | 31 interfaces, err = net.Interfaces() |
| paddy@0 | 32 if err != nil && name != "" { |
| paddy@0 | 33 return false |
| paddy@0 | 34 } |
| paddy@0 | 35 } |
| paddy@0 | 36 |
| paddy@0 | 37 for _, ifs := range interfaces { |
| paddy@0 | 38 if len(ifs.HardwareAddr) >= 6 && (name == "" || name == ifs.Name) { |
| paddy@0 | 39 if setNodeID(ifs.HardwareAddr) { |
| paddy@0 | 40 ifname = ifs.Name |
| paddy@0 | 41 return true |
| paddy@0 | 42 } |
| paddy@0 | 43 } |
| paddy@0 | 44 } |
| paddy@0 | 45 |
| paddy@0 | 46 // We found no interfaces with a valid hardware address. If name |
| paddy@0 | 47 // does not specify a specific interface generate a random Node ID |
| paddy@0 | 48 // (section 4.1.6) |
| paddy@0 | 49 if name == "" { |
| paddy@0 | 50 if nodeID == nil { |
| paddy@0 | 51 nodeID = make([]byte, 6) |
| paddy@0 | 52 } |
| paddy@0 | 53 randomBits(nodeID) |
| paddy@0 | 54 return true |
| paddy@0 | 55 } |
| paddy@0 | 56 return false |
| paddy@0 | 57 } |
| paddy@0 | 58 |
| paddy@0 | 59 // NodeID returns a slice of a copy of the current Node ID, setting the Node ID |
| paddy@0 | 60 // if not already set. |
| paddy@0 | 61 func NodeID() []byte { |
| paddy@0 | 62 if nodeID == nil { |
| paddy@0 | 63 SetNodeInterface("") |
| paddy@0 | 64 } |
| paddy@0 | 65 nid := make([]byte, 6) |
| paddy@0 | 66 copy(nid, nodeID) |
| paddy@0 | 67 return nid |
| paddy@0 | 68 } |
| paddy@0 | 69 |
| paddy@0 | 70 // SetNodeID sets the Node ID to be used for Version 1 UUIDs. The first 6 bytes |
| paddy@0 | 71 // of id are used. If id is less than 6 bytes then false is returned and the |
| paddy@0 | 72 // Node ID is not set. |
| paddy@0 | 73 func SetNodeID(id []byte) bool { |
| paddy@0 | 74 if setNodeID(id) { |
| paddy@0 | 75 ifname = "user" |
| paddy@0 | 76 return true |
| paddy@0 | 77 } |
| paddy@0 | 78 return false |
| paddy@0 | 79 } |
| paddy@0 | 80 |
| paddy@0 | 81 func setNodeID(id []byte) bool { |
| paddy@0 | 82 if len(id) < 6 { |
| paddy@0 | 83 return false |
| paddy@0 | 84 } |
| paddy@0 | 85 if nodeID == nil { |
| paddy@0 | 86 nodeID = make([]byte, 6) |
| paddy@0 | 87 } |
| paddy@0 | 88 copy(nodeID, id) |
| paddy@0 | 89 return true |
| paddy@0 | 90 } |
| paddy@0 | 91 |
| paddy@0 | 92 // NodeID returns the 6 byte node id encoded in uuid. It returns nil if uuid is |
| paddy@0 | 93 // not valid. The NodeID is only well defined for version 1 and 2 UUIDs. |
| paddy@0 | 94 func (uuid UUID) NodeID() []byte { |
| paddy@0 | 95 if len(uuid) != 16 { |
| paddy@0 | 96 return nil |
| paddy@0 | 97 } |
| paddy@0 | 98 node := make([]byte, 6) |
| paddy@0 | 99 copy(node, uuid[10:]) |
| paddy@0 | 100 return node |
| paddy@0 | 101 } |