Scott Baker | eee8dd8 | 2019-09-24 12:52:34 -0700 | [diff] [blame^] | 1 | // Copyright 2016 Google Inc. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style |
| 3 | // license that can be found in the LICENSE file. |
| 4 | |
| 5 | package uuid |
| 6 | |
| 7 | import ( |
| 8 | "io" |
| 9 | ) |
| 10 | |
| 11 | // randomBits completely fills slice b with random data. |
| 12 | func randomBits(b []byte) { |
| 13 | if _, err := io.ReadFull(rander, b); err != nil { |
| 14 | panic(err.Error()) // rand should never fail |
| 15 | } |
| 16 | } |
| 17 | |
| 18 | // xvalues returns the value of a byte as a hexadecimal digit or 255. |
| 19 | var xvalues = [256]byte{ |
| 20 | 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, |
| 21 | 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, |
| 22 | 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, |
| 23 | 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 255, 255, 255, 255, 255, 255, |
| 24 | 255, 10, 11, 12, 13, 14, 15, 255, 255, 255, 255, 255, 255, 255, 255, 255, |
| 25 | 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, |
| 26 | 255, 10, 11, 12, 13, 14, 15, 255, 255, 255, 255, 255, 255, 255, 255, 255, |
| 27 | 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, |
| 28 | 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, |
| 29 | 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, |
| 30 | 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, |
| 31 | 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, |
| 32 | 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, |
| 33 | 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, |
| 34 | 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, |
| 35 | 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, |
| 36 | } |
| 37 | |
| 38 | // xtob converts hex characters x1 and x2 into a byte. |
| 39 | func xtob(x1, x2 byte) (byte, bool) { |
| 40 | b1 := xvalues[x1] |
| 41 | b2 := xvalues[x2] |
| 42 | return (b1 << 4) | b2, b1 != 255 && b2 != 255 |
| 43 | } |