/* crypto/pqueue/pqueue.c */

 /* 

  * DTLS implementation written by Nagendra Modadugu

  * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.  

  */

 /* ====================================================================

  * Copyright (c) 1999-2005 The OpenSSL Project.  All rights reserved.

  *

  * Redistribution and use in source and binary forms, with or without

  * modification, are permitted provided that the following conditions

  * are met:

  *

  * 1. Redistributions of source code must retain the above copyright

  *    notice, this list of conditions and the following disclaimer. 

  *

  * 2. Redistributions in binary form must reproduce the above copyright

  *    notice, this list of conditions and the following disclaimer in

  *    the documentation and/or other materials provided with the

  *    distribution.

  *

  * 3. All advertising materials mentioning features or use of this

  *    software must display the following acknowledgment:

  *    "This product includes software developed by the OpenSSL Project

  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"

  *

  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to

  *    endorse or promote products derived from this software without

  *    prior written permission. For written permission, please contact

  *    openssl-core@OpenSSL.org.

  *

  * 5. Products derived from this software may not be called "OpenSSL"

  *    nor may "OpenSSL" appear in their names without prior written

  *    permission of the OpenSSL Project.

  *

  * 6. Redistributions of any form whatsoever must retain the following

  *    acknowledgment:

  *    "This product includes software developed by the OpenSSL Project

  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"

  *

  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY

  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR

  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT

  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;

  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,

  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED

  * OF THE POSSIBILITY OF SUCH DAMAGE.

  * ====================================================================

  *

  * This product includes cryptographic software written by Eric Young

  * (eay@cryptsoft.com).  This product includes software written by Tim

  * Hudson (tjh@cryptsoft.com).

  *

  */

 #include "cryptlib.h"

 #include <openssl/bn.h>

 #include <pqueue.h> 

 typedef struct _pqueue

 	{

 	pitem *items;

 	int count;

 	} pqueue_s;

 EXPORT_C pitem *

 pitem_new(PQ_64BIT priority, void *data)

 	{

 	pitem *item = (pitem *) OPENSSL_malloc(sizeof(pitem));

 	if (item == NULL) return NULL;

 	pq_64bit_init(&(item->priority));

 	pq_64bit_assign(&item->priority, &priority);

 	item->data = data;

 	item->next = NULL;

 	return item;

 	}

 EXPORT_C void

 pitem_free(pitem *item)

 	{

 	if (item == NULL) return;

 	pq_64bit_free(&(item->priority));

 	OPENSSL_free(item);

 	}

 EXPORT_C pqueue_s *

 pqueue_new()

 	{

 	pqueue_s *pq = (pqueue_s *) OPENSSL_malloc(sizeof(pqueue_s));

 	if (pq == NULL) return NULL;

 	memset(pq, 0x00, sizeof(pqueue_s));

 	return pq;

 	}

 EXPORT_C void

 pqueue_free(pqueue_s *pq)

 	{

 	if (pq == NULL) return;

 	OPENSSL_free(pq);

 	}

 EXPORT_C pitem *

 pqueue_insert(pqueue_s *pq, pitem *item)

 	{

 	pitem *curr, *next;

 	if (pq->items == NULL)

 		{

 		pq->items = item;

 		return item;

 		}

 	for(curr = NULL, next = pq->items; 

 		next != NULL;

 		curr = next, next = next->next)

 		{

 		if (pq_64bit_gt(&(next->priority), &(item->priority)))

 			{

 			item->next = next;

 			if (curr == NULL) 

 				pq->items = item;

 			else  

 				curr->next = item;

 			return item;

 			}

 		/* duplicates not allowed */

 		if (pq_64bit_eq(&(item->priority), &(next->priority)))

 			return NULL;

 		}

 	item->next = NULL;

 	curr->next = item;

 	return item;

 	}

 EXPORT_C pitem *

 pqueue_peek(pqueue_s *pq)

 	{

 	return pq->items;

 	}

 EXPORT_C pitem *

 pqueue_pop(pqueue_s *pq)

 	{

 	pitem *item = pq->items;

 	if (pq->items != NULL)

 		pq->items = pq->items->next;

 	return item;

 	}

 EXPORT_C pitem *

 pqueue_find(pqueue_s *pq, PQ_64BIT priority)

 	{

 	pitem *next, *prev = NULL;

 	pitem *found = NULL;

 	if ( pq->items == NULL)

 		return NULL;

 	for ( next = pq->items; next->next != NULL; 

 		  prev = next, next = next->next)

 		{

 		if ( pq_64bit_eq(&(next->priority), &priority))

 			{

 			found = next;

 			break;

 			}

 		}

 	/* check the one last node */

 	if ( pq_64bit_eq(&(next->priority), &priority))

 		found = next;

 	if ( ! found)

 		return NULL;

 #if 0 /* find works in peek mode */

 	if ( prev == NULL)

 		pq->items = next->next;

 	else

 		prev->next = next->next;

 #endif

 	return found;

 	}

 #if PQ_64BIT_IS_INTEGER

 EXPORT_C void

 pqueue_print(pqueue_s *pq)

 	{

 	pitem *item = pq->items;

 	while(item != NULL)

 		{

 		printf("item\t" PQ_64BIT_PRINT "\n", item->priority);

 		item = item->next;

 		}

 	}

 #endif

 EXPORT_C pitem *

 pqueue_iterator(pqueue_s *pq)

 	{

 	return pqueue_peek(pq);

 	}

 EXPORT_C pitem *

 pqueue_next(pitem **item)

 	{

 	pitem *ret;

 	if ( item == NULL || *item == NULL)

 		return NULL;

 	/* *item != NULL */

 	ret = *item;

 	*item = (*item)->next;

 	return ret;

 	}