1 /*- 2 * Copyright 2020 Conrad Meyer <cem@FreeBSD.org>. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23 * SUCH DAMAGE. 24 */ 25 26 #pragma once 27 28 /* 29 * For each of the currently supported random number generators, we have a 30 * break value on the amount of state information (you need at least this 31 * many bytes of state info to support this random number generator), a degree 32 * for the polynomial (actually a trinomial) that the R.N.G. is based on, and 33 * the separation between the two lower order coefficients of the trinomial. 34 */ 35 #define TYPE_0 0 /* linear congruential */ 36 #define BREAK_0 8 37 #define DEG_0 0 38 #define SEP_0 0 39 40 #define TYPE_1 1 /* x**7 + x**3 + 1 */ 41 #define BREAK_1 32 42 #define DEG_1 7 43 #define SEP_1 3 44 45 #define TYPE_2 2 /* x**15 + x + 1 */ 46 #define BREAK_2 64 47 #define DEG_2 15 48 #define SEP_2 1 49 50 #define TYPE_3 3 /* x**31 + x**3 + 1 */ 51 #define BREAK_3 128 52 #define DEG_3 31 53 #define SEP_3 3 54 55 #define TYPE_4 4 /* x**63 + x + 1 */ 56 #define BREAK_4 256 57 #define DEG_4 63 58 #define SEP_4 1 59 60 /* 61 * Array versions of the above information to make code run faster -- 62 * relies on fact that TYPE_i == i. 63 */ 64 #define MAX_TYPES 5 /* max number of types above */ 65 66 /* A full instance of the random(3) generator. */ 67 struct __random_state { 68 uint32_t *rst_fptr; 69 uint32_t *rst_rptr; 70 uint32_t *rst_state; 71 int rst_type; 72 int rst_deg; 73 int rst_sep; 74 uint32_t *rst_end_ptr; 75 /* Flexible array member must be last. */ 76 uint32_t rst_randtbl[]; 77 }; 78 79 struct __random_state *allocatestate(unsigned type); 80 int initstate_r(struct __random_state *, unsigned, uint32_t *, size_t); 81 long random_r(struct __random_state *); 82 void srandom_r(struct __random_state *, unsigned); 83 void srandomdev_r(struct __random_state *); 84