1 /*- 2 * Copyright (c) 1988, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Timothy C. Stoehr. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * @(#)random.c 8.1 (Berkeley) 5/31/93 33 * $FreeBSD: src/games/rogue/random.c,v 1.6 1999/11/30 03:49:26 billf Exp $ 34 * $DragonFly: src/games/rogue/random.c,v 1.3 2006/09/02 19:31:07 pavalos Exp $ 35 */ 36 37 #include "rogue.h" 38 39 /* 40 * random.c 41 * 42 * This source herein may be modified and/or distributed by anybody who 43 * so desires, with the following restrictions: 44 * 1.) No portion of this notice shall be removed. 45 * 2.) Credit shall not be taken for the creation of this source. 46 * 3.) This code is not to be traded, sold, or used for personal 47 * gain or profit. 48 * 49 */ 50 51 int 52 get_rand(int x, int y) 53 { 54 int r, t; 55 long lr; 56 57 if (x > y) { 58 t = y; 59 y = x; 60 x = t; 61 } 62 lr = rrandom(); 63 lr &= (long) 0x00003fff; 64 r = (int)lr; 65 r = (r % ((y - x) + 1)) + x; 66 return(r); 67 } 68 69 boolean 70 rand_percent(int percentage) 71 { 72 return(get_rand(1, 100) <= percentage); 73 } 74 75 boolean 76 coin_toss(void) 77 { 78 return(((rrandom() & 01) ? 1 : 0)); 79 } 80