ducky/devices
2015-11-27
Parent:b6494e1a499e
ducky/devices/vendor/code.google.com/p/go-uuid/uuid/version4.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 // Random returns a Random (Version 4) UUID or panics. |
| paddy@0 | 8 // |
| paddy@0 | 9 // The strength of the UUIDs is based on the strength of the crypto/rand |
| paddy@0 | 10 // package. |
| paddy@0 | 11 // |
| paddy@0 | 12 // A note about uniqueness derived from from the UUID Wikipedia entry: |
| paddy@0 | 13 // |
| paddy@0 | 14 // Randomly generated UUIDs have 122 random bits. One's annual risk of being |
| paddy@0 | 15 // hit by a meteorite is estimated to be one chance in 17 billion, that |
| paddy@0 | 16 // means the probability is about 0.00000000006 (6 × 10−11), |
| paddy@0 | 17 // equivalent to the odds of creating a few tens of trillions of UUIDs in a |
| paddy@0 | 18 // year and having one duplicate. |
| paddy@0 | 19 func NewRandom() UUID { |
| paddy@0 | 20 uuid := make([]byte, 16) |
| paddy@0 | 21 randomBits([]byte(uuid)) |
| paddy@0 | 22 uuid[6] = (uuid[6] & 0x0f) | 0x40 // Version 4 |
| paddy@0 | 23 uuid[8] = (uuid[8] & 0x3f) | 0x80 // Variant is 10 |
| paddy@0 | 24 return uuid |
| paddy@0 | 25 } |