1 | /* |
2 | * Copyright (C) 2006, 2007, 2008 Apple Inc. All rights reserved. |
3 | * (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/) |
4 | * Copyright (C) 2013 Andrew Bortz. All rights reserved. |
5 | * |
6 | * Redistribution and use in source and binary forms, with or without |
7 | * modification, are permitted provided that the following conditions |
8 | * are met: |
9 | * 1. Redistributions of source code must retain the above copyright |
10 | * notice, this list of conditions and the following disclaimer. |
11 | * 2. Redistributions in binary form must reproduce the above copyright |
12 | * notice, this list of conditions and the following disclaimer in the |
13 | * documentation and/or other materials provided with the distribution. |
14 | * |
15 | * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY |
16 | * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
17 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
18 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR |
19 | * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
20 | * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
21 | * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
22 | * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY |
23 | * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
24 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
25 | * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
26 | */ |
27 | |
28 | #include "config.h" |
29 | #include <wtf/RandomNumber.h> |
30 | |
31 | #include <limits> |
32 | #include <limits.h> |
33 | #include <stdint.h> |
34 | #include <stdlib.h> |
35 | #include <wtf/CryptographicallyRandomNumber.h> |
36 | #include <wtf/RandomNumberSeed.h> |
37 | #include <wtf/WeakRandom.h> |
38 | |
39 | namespace WTF { |
40 | |
41 | double randomNumber() |
42 | { |
43 | uint32_t bits = cryptographicallyRandomNumber(); |
44 | return static_cast<double>(bits) / (static_cast<double>(std::numeric_limits<uint32_t>::max()) + 1.0); |
45 | } |
46 | |
47 | unsigned weakRandomUint32() |
48 | { |
49 | // We don't care about thread safety. WeakRandom just uses POD types, |
50 | // and racy access just increases randomness. |
51 | static WeakRandom s_weakRandom; |
52 | return s_weakRandom.getUint32(); |
53 | } |
54 | |
55 | } |
56 | |