| 1 | /* |
|---|---|
| 2 | * grandom.cc |
| 3 | * |
| 4 | * This file is licensed under the GPLv2 or later |
| 5 | * |
| 6 | * Pseudo-random number generation |
| 7 | * |
| 8 | * Copyright (C) 2012 Fabio D'Urso <fabiodurso@hotmail.it> |
| 9 | * Copyright (C) 2018 Adam Reichold <adam.reichold@t-online.de> |
| 10 | * Copyright (C) 2022 Albert Astals Cid <aacid@kde.org> |
| 11 | */ |
| 12 | |
| 13 | #include "grandom.h" |
| 14 | |
| 15 | #include <random> |
| 16 | |
| 17 | namespace { |
| 18 | |
| 19 | auto &grandom_engine() |
| 20 | { |
| 21 | static thread_local std::default_random_engine engine { std::random_device {}() }; |
| 22 | return engine; |
| 23 | } |
| 24 | |
| 25 | } |
| 26 | |
| 27 | void grandom_fill(unsigned char *buff, int size) |
| 28 | { |
| 29 | auto &engine = grandom_engine(); |
| 30 | std::uniform_int_distribution<unsigned short> distribution { std::numeric_limits<unsigned char>::min(), std::numeric_limits<unsigned char>::max() }; |
| 31 | for (int index = 0; index < size; ++index) { |
| 32 | buff[index] = static_cast<unsigned char>(distribution(engine)); |
| 33 | } |
| 34 | } |
| 35 | |
| 36 | double grandom_double() |
| 37 | { |
| 38 | auto &engine = grandom_engine(); |
| 39 | return std::generate_canonical<double, std::numeric_limits<double>::digits>(urng&: engine); |
| 40 | } |
| 41 |