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 EXPORT_C 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 EXPORT_C 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 EXPORT_C 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 EXPORT_C void

   105 pqueue_free(pqueue_s *pq)

   106 	{

   107 	if (pq == NULL) return;

   108 

   109 	OPENSSL_free(pq);

   110 	}

   111 

   112 EXPORT_C 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 EXPORT_C pitem *

   150 pqueue_peek(pqueue_s *pq)

   151 	{

   152 	return pq->items;

   153 	}

   154 

   155 EXPORT_C 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 EXPORT_C 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 EXPORT_C 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 EXPORT_C pitem *

   217 pqueue_iterator(pqueue_s *pq)

   218 	{

   219 	return pqueue_peek(pq);

   220 	}

   221 

   222 EXPORT_C 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 	}