random/random.c

   1 /*
   2  * This file is part of the Nice GLib ICE library.
   3  *
   4  * (C) 2006-2008 Collabora Ltd.
   5  *  Contact: Dafydd Harries
   6  * (C) 2006-2008 Nokia Corporation. All rights reserved.
   7  *  Contact: Kai Vehmanen
   8  *
   9  * The contents of this file are subject to the Mozilla Public License Version
  10  * 1.1 (the "License"); you may not use this file except in compliance with
  11  * the License. You may obtain a copy of the License at
  12  * http://www.mozilla.org/MPL/
  13  *
  14  * Software distributed under the License is distributed on an "AS IS" basis,
  15  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  16  * for the specific language governing rights and limitations under the
  17  * License.
  18  *
  19  * The Original Code is the Nice GLib ICE library.
  20  *
  21  * The Initial Developers of the Original Code are Collabora Ltd and Nokia
  22  * Corporation. All Rights Reserved.
  23  *
  24  * Contributors:
  25  *   Dafydd Harries, Collabora Ltd.
  26  *   Youness Alaoui, Collabora Ltd.
  27  *   Kai Vehmanen, Nokia
  28  *
  29  * Alternatively, the contents of this file may be used under the terms of the
  30  * the GNU Lesser General Public License Version 2.1 (the "LGPL"), in which
  31  * case the provisions of LGPL are applicable instead of those above. If you
  32  * wish to allow use of your version of this file only under the terms of the
  33  * LGPL and not to allow others to use your version of this file under the
  34  * MPL, indicate your decision by deleting the provisions above and replace
  35  * them with the notice and other provisions required by the LGPL. If you do
  36  * not delete the provisions above, a recipient may use your version of this
  37  * file under either the MPL or the LGPL.
  38  */
  39 #ifdef HAVE_CONFIG_H
  40 # include "config.h"
  41 #endif
  42
  43 #include <string.h>
  44
  45 #include "random.h"
  46 #include "random-glib.h"
  47
  48 static NiceRNG * (*nice_rng_new_func) (void) = NULL;
  49
  50 /*
  51  * Creates a new random number generator instance.
  52  */
  53 NiceRNG *
  54 nice_rng_new (void)
  55 {
  56   if (nice_rng_new_func == NULL)
  57     return nice_rng_glib_new ();
  58   else
  59     return nice_rng_new_func ();
  60 }
  61
  62 /*
  63  * Sets a new generator function.
  64  */
  65 void
  66 nice_rng_set_new_func (NiceRNG * (*func) (void))
  67 {
  68   nice_rng_new_func = func;
  69 }
  70
  71 /*
  72  * Frees the random number generator instance.
  73  *
  74  * @param rng context
  75  */
  76 void
  77 nice_rng_free (NiceRNG *rng)
  78 {
  79   rng->free (rng);
  80 }
  81
  82 /*
  83  * Generates random octets.
  84  *
  85  * @param rng context
  86  * @param len number of octets to product
  87  * @param buf buffer to store the results
  88  */
  89 void
  90 nice_rng_generate_bytes (NiceRNG *rng, guint len, gchar *buf)
  91 {
  92   rng->generate_bytes (rng, len, buf);
  93 }
  94
  95 /*
  96  * Generates a random unsigned integer.
  97  *
  98  * @param rng context
  99  * @param low closed lower bound
 100  * @param high open upper bound
 101  */
 102 guint
 103 nice_rng_generate_int (NiceRNG *rng, guint low, guint high)
 104 {
 105   return rng->generate_int (rng, low, high);
 106 }
 107
 108 /*
 109  * Generates a stream of octets containing only characters
 110  * with ASCII codecs of 0x41-5A (A-Z), 0x61-7A (a-z),
 111  * 0x30-39 (0-9), 0x2b (+) and 0x2f (/). This matches
 112  * the definition of 'ice-char' in ICE Ispecification,
 113  * section 15.1 (ID-16).
 114  *
 115  * @param rng context
 116  * @param len number of octets to product
 117  * @param buf buffer to store the results
 118  */
 119 void
 120 nice_rng_generate_bytes_print (NiceRNG *rng, guint len, gchar *buf)
 121 {
 122   guint i;
 123   const gchar *chars =
 124     "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
 125     "abcdefghijklmnopqrstuvwxyz"
 126     "0123456789"
 127     "+/";
 128
 129   for (i = 0; i < len; i++)
 130     buf[i] = chars[nice_rng_generate_int (rng, 0, strlen (chars))];
 131 }
 132