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. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)random.c 8.1 (Berkeley) 5/31/93 37 * $FreeBSD: src/games/rogue/random.c,v 1.6 1999/11/30 03:49:26 billf Exp $ 38 * $DragonFly: src/games/rogue/random.c,v 1.3 2006/09/02 19:31:07 pavalos Exp $ 39 */ 40 41 #include "rogue.h" 42 43 /* 44 * random.c 45 * 46 * This source herein may be modified and/or distributed by anybody who 47 * so desires, with the following restrictions: 48 * 1.) No portion of this notice shall be removed. 49 * 2.) Credit shall not be taken for the creation of this source. 50 * 3.) This code is not to be traded, sold, or used for personal 51 * gain or profit. 52 * 53 */ 54 55 int 56 get_rand(int x, int y) 57 { 58 int r, t; 59 long lr; 60 61 if (x > y) { 62 t = y; 63 y = x; 64 x = t; 65 } 66 lr = rrandom(); 67 lr &= (long) 0x00003fff; 68 r = (int) lr; 69 r = (r % ((y - x) + 1)) + x; 70 return(r); 71 } 72 73 boolean 74 rand_percent(int percentage) 75 { 76 return(get_rand(1, 100) <= percentage); 77 } 78 79 boolean 80 coin_toss(void) 81 { 82 83 return(((rrandom() & 01) ? 1 : 0)); 84 } 85