GÉNÉRATEUR DE NOMBRES PSEUDO-ALÉATOIRES (PSEUDO RANDOM NUMBER GENERATOR - LFSR)

/* just a sample, see the zip  file for more */

/*
 * Copyright (c) 2004-2005,  contax. All rights reserved.
 * 
 * LICENSE TERMS
 * 
 * The free distribution and use of this software in both source and
 * binary form is allowed (with or without changes) provided that:
 * 
 * 1. distributions of this source code include the above copyright
 * notice, this list of conditions and the following disclaimer;
 * 
 * 2. distributions in binary form include the above copyright notice,
 * this list of conditions and the following disclaimer in the
 * documentation and/or other associated materials;
 *
 * DISCLAIMER
 * 
 * This software is provided 'as is' with no explicit or implied
 * warranties in respect of its properties, including, but not limited to, 
 * correctness and fitness for purpose. 
 */

#include <unistd.h>
#include <sys/mman.h>
#include <stdio.h>
#include <errno.h>
#include "destroy.h"
#include "./lfsr/lfsr.h"
#define _RANDOM_LOCAL
#include "random.h"
#undef  _RANDOM_LOCAL


LFSR_CTX       *
rand_init(int fd)
{
    LFSR_CTX       *ctx;
    uint32_t       *sd;

    if (NULL == lfsr_alloc(ctx)) {
        perror("lfsr_alloc");
        return NULL;
    }
if ((void *) -1 == (sd = (uint32_t *)
                    mmap(0, 31 * sizeof(uint32_t), PROT_READ |
                         PROT_WRITE, MAP_PRIVATE, fd, 0)))
    {
        perror("projection");
        lfsr_ctx_free(ctx);
        return NULL;
    }
    (void) lfsr_init(ctx, sd);
    munmap(sd, 31 * sizeof(uint32_t));

    return ctx;
}