crypto/openssl/crypto/pqueue/pqueue.c

   1 /* crypto/pqueue/pqueue.c */
   2 /*
   3  * DTLS implementation written by Nagendra Modadugu
   4  * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
   5  */
   6 /* ====================================================================
   7  * Copyright (c) 1999-2005 The OpenSSL Project.  All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  *
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  *
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in
  18  *    the documentation and/or other materials provided with the
  19  *    distribution.
  20  *
  21  * 3. All advertising materials mentioning features or use of this
  22  *    software must display the following acknowledgment:
  23  *    "This product includes software developed by the OpenSSL Project
  24  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
  25  *
  26  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  27  *    endorse or promote products derived from this software without
  28  *    prior written permission. For written permission, please contact
  29  *    openssl-core@OpenSSL.org.
  30  *
  31  * 5. Products derived from this software may not be called "OpenSSL"
  32  *    nor may "OpenSSL" appear in their names without prior written
  33  *    permission of the OpenSSL Project.
  34  *
  35  * 6. Redistributions of any form whatsoever must retain the following
  36  *    acknowledgment:
  37  *    "This product includes software developed by the OpenSSL Project
  38  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
  39  *
  40  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  41  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  43  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  44  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  45  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  46  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  47  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  49  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  50  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  51  * OF THE POSSIBILITY OF SUCH DAMAGE.
  52  * ====================================================================
  53  *
  54  * This product includes cryptographic software written by Eric Young
  55  * (eay@cryptsoft.com).  This product includes software written by Tim
  56  * Hudson (tjh@cryptsoft.com).
  57  *
  58  */
  59
  60 #include "cryptlib.h"
  61 #include <openssl/bn.h>
  62 #include "pqueue.h"
  63
  64 typedef struct _pqueue
  65         {
  66         pitem *items;
  67         int count;
  68         } pqueue_s;
  69
  70 pitem *
  71 pitem_new(PQ_64BIT priority, void *data)
  72         {
  73         pitem *item = (pitem *) OPENSSL_malloc(sizeof(pitem));
  74         if (item == NULL) return NULL;
  75
  76         pq_64bit_init(&(item->priority));
  77         pq_64bit_assign(&item->priority, &priority);
  78
  79         item->data = data;
  80         item->next = NULL;
  81
  82         return item;
  83         }
  84
  85 void
  86 pitem_free(pitem *item)
  87         {
  88         if (item == NULL) return;
  89
  90         pq_64bit_free(&(item->priority));
  91         OPENSSL_free(item);
  92         }
  93
  94 pqueue_s *
  95 pqueue_new()
  96         {
  97         pqueue_s *pq = (pqueue_s *) OPENSSL_malloc(sizeof(pqueue_s));
  98         if (pq == NULL) return NULL;
  99
 100         memset(pq, 0x00, sizeof(pqueue_s));
 101         return pq;
 102         }
 103
 104 void
 105 pqueue_free(pqueue_s *pq)
 106         {
 107         if (pq == NULL) return;
 108
 109         OPENSSL_free(pq);
 110         }
 111
 112 pitem *
 113 pqueue_insert(pqueue_s *pq, pitem *item)
 114         {
 115         pitem *curr, *next;
 116
 117         if (pq->items == NULL)
 118                 {
 119                 pq->items = item;
 120                 return item;
 121                 }
 122
 123         for(curr = NULL, next = pq->items;
 124                 next != NULL;
 125                 curr = next, next = next->next)
 126                 {
 127                 if (pq_64bit_gt(&(next->priority), &(item->priority)))
 128                         {
 129                         item->next = next;
 130
 131                         if (curr == NULL)
 132                                 pq->items = item;
 133                         else
 134                                 curr->next = item;
 135
 136                         return item;
 137                         }
 138                 /* duplicates not allowed */
 139                 if (pq_64bit_eq(&(item->priority), &(next->priority)))
 140                         return NULL;
 141                 }
 142
 143         item->next = NULL;
 144         curr->next = item;
 145
 146         return item;
 147         }
 148
 149 pitem *
 150 pqueue_peek(pqueue_s *pq)
 151         {
 152         return pq->items;
 153         }
 154
 155 pitem *
 156 pqueue_pop(pqueue_s *pq)
 157         {
 158         pitem *item = pq->items;
 159
 160         if (pq->items != NULL)
 161                 pq->items = pq->items->next;
 162
 163         return item;
 164         }
 165
 166 pitem *
 167 pqueue_find(pqueue_s *pq, PQ_64BIT priority)
 168         {
 169         pitem *next, *prev = NULL;
 170         pitem *found = NULL;
 171
 172         if ( pq->items == NULL)
 173                 return NULL;
 174
 175         for ( next = pq->items; next->next != NULL;
 176                   prev = next, next = next->next)
 177                 {
 178                 if ( pq_64bit_eq(&(next->priority), &priority))
 179                         {
 180                         found = next;
 181                         break;
 182                         }
 183                 }
 184
 185         /* check the one last node */
 186         if ( pq_64bit_eq(&(next->priority), &priority))
 187                 found = next;
 188
 189         if ( ! found)
 190                 return NULL;
 191
 192 #if 0 /* find works in peek mode */
 193         if ( prev == NULL)
 194                 pq->items = next->next;
 195         else
 196                 prev->next = next->next;
 197 #endif
 198
 199         return found;
 200         }
 201
 202 #if PQ_64BIT_IS_INTEGER
 203 void
 204 pqueue_print(pqueue_s *pq)
 205         {
 206         pitem *item = pq->items;
 207
 208         while(item != NULL)
 209                 {
 210                 printf("item\t" PQ_64BIT_PRINT "\n", item->priority);
 211                 item = item->next;
 212                 }
 213         }
 214 #endif
 215
 216 pitem *
 217 pqueue_iterator(pqueue_s *pq)
 218         {
 219         return pqueue_peek(pq);
 220         }
 221
 222 pitem *
 223 pqueue_next(pitem **item)
 224         {
 225         pitem *ret;
 226
 227         if ( item == NULL || *item == NULL)
 228                 return NULL;
 229
 230
 231         /* *item != NULL */
 232         ret = *item;
 233         *item = (*item)->next;
 234
 235         return ret;
 236         }