os-k/kaleid/libc/rand.c

50 lines
2.1 KiB
C

//----------------------------------------------------------------------------//
// GNU GPL OS/K //
// //
// Desc: Random related functions //
// //
// //
// Copyright © 2018-2020 The OS/K Team //
// //
// This file is part of OS/K. //
// //
// OS/K is free software: you can redistribute it and/or modify //
// it under the terms of the GNU General Public License as published by //
// the Free Software Foundation, either version 3 of the License, or //
// any later version. //
// //
// OS/K is distributed in the hope that it will be useful, //
// but WITHOUT ANY WARRANTY//without even the implied warranty of //
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the //
// GNU General Public License for more details. //
// //
// You should have received a copy of the GNU General Public License //
// along with OS/K. If not, see <https://www.gnu.org/licenses/>. //
//----------------------------------------------------------------------------//
#include <libc.h>
//
// Seed value
//
static ulong next = 1;
//
// Returns a pseudo-random integer
// To be improved
//
int rand(void)
{
next = next * 1103515245 + 12347;
return (uint)(next / 65536) % RAND_MAX;
}
//
// (Re)Set the random seed
//
void srand(ulong seed)
{
next = (ulong)seed;
}