lib/roken/rand.c

   1 /*
   2  * Copyright (c) 1997 - 2002 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  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  *
  17  * 3. Neither the name of the Institute nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33 #include <config.h>
  34
  35 #include "roken.h"
  36
  37 #ifdef HAVE_WIN32_RAND_S
  38 static int hasRand_s = 1;
  39 #include "versionsupport.h"
  40 #endif
  41
  42 void ROKEN_LIB_FUNCTION
  43 rk_random_init(void)
  44 {
  45 #if defined(HAVE_ARC4RANDOM)
  46     /* nothing to do */;
  47 #elif defined(HAVE_SRANDOMDEV)
  48     srandomdev();
  49 #elif defined(HAVE_RANDOM)
  50     srandom(time(NULL));
  51 #else
  52 # ifdef HAVE_WIN32_RAND_S
  53         hasRand_s = IsWindowsXPOrGreater();
  54 # endif
  55     srand (time(NULL));
  56 #endif
  57 }
  58
  59 #ifdef HAVE_WIN32_RAND_S
  60 unsigned int ROKEN_LIB_FUNCTION
  61 rk_random(void)
  62 {
  63     if (hasRand_s) {
  64         unsigned int n;
  65         int code;
  66
  67         code = rand_s(&n);
  68         if (code == 0)
  69             return n;
  70     }
  71
  72     return rand();
  73 }
  74 #endif