1/***************************************************************************
2 *                                  _   _ ____  _
3 *  Project                     ___| | | |  _ \| |
4 *                             / __| | | | |_) | |
5 *                            | (__| |_| |  _ <| |___
6 *                             \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) 1998 - 2009, Daniel Stenberg, <daniel@haxx.se>, et al.
9 *
10 * This software is licensed as described in the file COPYING, which
11 * you should have received as part of this distribution. The terms
12 * are also available at http://curl.haxx.se/docs/copyright.html.
13 *
14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15 * copies of the Software, and permit persons to whom the Software is
16 * furnished to do so, under the terms of the COPYING file.
17 *
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
20 *
21 ***************************************************************************/
22
23#include "setup.h"
24
25#include <curl/curl.h>
26
27#include "curl_rand.h"
28
29#define _MPRINTF_REPLACE /* use our functions only */
30#include <curl/mprintf.h>
31
32#include "curl_memory.h"
33/* The last #include file should be: */
34#include "memdebug.h"
35
36/* Private pseudo-random number seed. Unsigned integer >= 32bit. Threads
37   mutual exclusion is not implemented to acess it since we do not require
38   high quality random numbers (only used in form boudary generation). */
39
40static unsigned int randseed;
41
42/* Pseudo-random number support. */
43
44unsigned int Curl_rand(void)
45{
46  unsigned int r;
47  /* Return an unsigned 32-bit pseudo-random number. */
48  r = randseed = randseed * 1103515245 + 12345;
49  return (r << 16) | ((r >> 16) & 0xFFFF);
50}
51
52void Curl_srand(void)
53{
54  /* Randomize pseudo-random number sequence. */
55
56  randseed = (unsigned int) time(NULL);
57  Curl_rand();
58  Curl_rand();
59  Curl_rand();
60}
61
62