random/random.c

   1 /*
   2  * This file is part of the Nice GLib ICE library.
   3  *
   4  * (C) 2006, 2007 Collabora Ltd.
   5  *  Contact: Dafydd Harries
   6  * (C) 2006, 2007 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  *   Kai Vehmanen, Nokia
  27  *
  28  * Alternatively, the contents of this file may be used under the terms of the
  29  * the GNU Lesser General Public License Version 2.1 (the "LGPL"), in which
  30  * case the provisions of LGPL are applicable instead of those above. If you
  31  * wish to allow use of your version of this file only under the terms of the
  32  * LGPL and not to allow others to use your version of this file under the
  33  * MPL, indicate your decision by deleting the provisions above and replace
  34  * them with the notice and other provisions required by the LGPL. If you do
  35  * not delete the provisions above, a recipient may use your version of this
  36  * file under either the MPL or the LGPL.
  37  */
  38 #ifdef HAVE_CONFIG_H
  39 # include "config.h"
  40 #endif
  41
  42 #include <string.h>
  43
  44 #include "random.h"
  45 #include "random-glib.h"
  46
  47 static NiceRNG * (*nice_rng_new_func) (void) = NULL;
  48
  49 /**
  50  * Creates a new random number generator instance.
  51  */
  52 NICEAPI_EXPORT NiceRNG *
  53 nice_rng_new (void)
  54 {
  55   if (nice_rng_new_func == NULL)
  56     return nice_rng_glib_new ();
  57   else
  58     return nice_rng_new_func ();
  59 }
  60
  61 /**
  62  * Sets a new generator function.
  63  */
  64 NICEAPI_EXPORT void
  65 nice_rng_set_new_func (NiceRNG * (*func) (void))
  66 {
  67   nice_rng_new_func = func;
  68 }
  69
  70 /**
  71  * Frees the random number generator instance.
  72  *
  73  * @param rng context
  74  */
  75 NICEAPI_EXPORT void
  76 nice_rng_free (NiceRNG *rng)
  77 {
  78   rng->free (rng);
  79 }
  80
  81 /**
  82  * Generates random octets.
  83  *
  84  * @param rng context
  85  * @param len number of octets to product
  86  * @param buf buffer to store the results
  87  */
  88 NICEAPI_EXPORT void
  89 nice_rng_generate_bytes (NiceRNG *rng, guint len, gchar *buf)
  90 {
  91   rng->generate_bytes (rng, len, buf);
  92 }
  93
  94 /**
  95  * Generates a random unsigned integer.
  96  *
  97  * @param rng context
  98  * @param low closed lower bound
  99  * @param high open upper bound
 100  */
 101 NICEAPI_EXPORT guint
 102 nice_rng_generate_int (NiceRNG *rng, guint low, guint high)
 103 {
 104   return rng->generate_int (rng, low, high);
 105 }
 106
 107 /**
 108  * Generates a stream of octets containing only characters
 109  * with ASCII codecs of 0x41-5A (A-Z), 0x61-7A (a-z),
 110  * 0x30-39 (0-9), 0x2b (+) and 0x2f (/). This matches
 111  * the definition of 'ice-char' in ICE Ispecification,
 112  * section 15.1 (ID-16).
 113  *
 114  * @param rng context
 115  * @param len number of octets to product
 116  * @param buf buffer to store the results
 117  */
 118 NICEAPI_EXPORT void
 119 nice_rng_generate_bytes_print (NiceRNG *rng, guint len, gchar *buf)
 120 {
 121   guint i;
 122   const gchar *chars =
 123     "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
 124     "abcdefghijklmnopqrstuvwxyz"
 125     "0123456789"
 126     "+/";
 127
 128   for (i = 0; i < len; i++)
 129     buf[i] = chars[nice_rng_generate_int (rng, 0, strlen (chars))];
 130 }
 131