1 // random.cpp - Random number generation.
3 // (c) 2016-2017 Xestia Software Development.
5 // This file is part of Xestia Calendar.
7 // Xestia Calendar is free software: you can redistribute it and/or modify
8 // it under the terms of the GNU General Public License as published by the
9 // Free Software Foundation, version 3 of the license.
11 // Xestia Calendar is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
16 // You should have received a copy of the GNU General Public License along
17 // with Xestia Calendar. If not, see <http://www.gnu.org/licenses/>
23 int GenerateRandomNumber(int powerOf){
26 // Seed the randomiser!
30 int powerOfCalculation = (int)pow(2, (double)powerOf);
31 int randomNumber = rand() % powerOfCalculation;
34 // Get four bytes from /dev/urandom.
38 ifstream randomFilehandle("/dev/urandom", ios::in|ios::binary);
39 char *randomDataInput;
41 randomDataInput = new char [4];
42 randomFilehandle.read(randomDataInput, 4);
44 // Seed the randomiser!
46 srand(*randomDataInput);
47 delete [] randomDataInput;
49 randomFilehandle.close();
51 int powerOfCalculation = (int)pow(2, (double)powerOf);
52 int randomNumber = rand() % powerOfCalculation;