APPS/baselib/llist.c - external/sctp-refimpl - Git at Google

 /*	$Header: /usr/sctpCVS/APPS/baselib/llist.c,v 1.3 2008-12-26 14:45:12 randall Exp $ */

 /*
  * Copyright (C) 2002 Cisco Systems Inc,
  * 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. Neither the name of the project nor the names of its contributors
  *    may be used to endorse or promote products derived from this software
  *    without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  * ANY EXPRESS 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 PROJECT OR 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.
  */

 #include "llist.h"

 llist_t *
 llist_create()
 {
 	llist_t *o;

 	o = (llist_t *) CALLOC(1, sizeof(llist_t));
 	if (o == NULL)
 		return (NULL);
 	o->curr = o->currm1 = NULL;
 	o->cntIn = 0;
 	o->n2last = o->last = NULL;
 	o->wrapFlag = 0;
 	return (o);
 }

 void
 llist_destroy(llist_t * o)
 {
 	if (o == NULL)
 		return;

 	llist_clear(o);
 	FREE(o);
 }

 int
 llist_append(llist_t * o, void *a)
 {
 	llist_slink *tmp;

 	if (o == NULL)
 		return (LIB_STATUS_BAD);

 	if (o->last) {
 		/* entries in the list */
 		o->n2last = o->last;
 		tmp = (llist_slink *) CALLOC(1, sizeof(llist_slink));
 		if (tmp == NULL) {
 			return (LIB_STATUS_BAD);
 		}
 		tmp->ent = a;
 		tmp->next = o->last->next;
 		o->last->next = tmp;
 		o->last = tmp;
 	} else {
 		/* no entires in the list */
 		o->n2last = o->last = (llist_slink *) CALLOC(1, sizeof(llist_slink));
 		if (o->last == NULL) {
 			return (LIB_STATUS_BAD);
 		}
 		o->last->ent = a;
 		o->last->next = NULL;
 		o->last->next = o->last;
 	}
 	o->cntIn++;
 	return (LIB_STATUS_GOOD);
 }

 int
 llist_appendslink(llist_t * o, llist_slink * a)
 {
 	if (o == NULL)
 		return (LIB_STATUS_BAD);

 	if (a == NULL)
 		/*
 		 * We don't allow a NULL llist_slink struct to be entered in
 		 * the list
 		 */
 		return (LIB_STATUS_BAD);

 	if (o->last) {
 		/* one or more entries in the list */
 		o->n2last = o->last;
 		a->next = o->last->next;
 		o->last->next = a;
 		o->last = a;
 	} else {
 		/* no entries in list. */
 		o->n2last = o->last = a;
 		o->last->next = o->last;
 	}
 	o->cntIn++;
 	return (LIB_STATUS_GOOD);
 }

 int
 llist_insert(llist_t * o, void *a)
 {
 	llist_slink *tmp;

 	if (o == NULL)
 		return (LIB_STATUS_BAD);

 	if (o->last) {
 		tmp = (llist_slink *) CALLOC(1, sizeof(llist_slink));
 		if (tmp == NULL) {
 			return (LIB_STATUS_BAD);
 		}
 		tmp->ent = a;
 		tmp->next = o->last->next;
 		o->last->next = tmp;
 	} else {
 		o->n2last = o->last = (llist_slink *) CALLOC(1, sizeof(llist_slink));
 		if (o->last == NULL) {
 			return (LIB_STATUS_BAD);
 		}
 		o->last->ent = a;
 		o->last->next = NULL;
 		o->last->next = o->last;
 	}
 	o->cntIn++;
 	return (LIB_STATUS_GOOD);
 }

 void
 llist_clear(llist_t * o)
 {
 	void *pp;

 	if (o == NULL)
 		return;

 	while ((pp = llist_getNext(o)) != NULL) {
 		pp = NULL;
 	}
 	o->n2last = o->last = NULL;
 	o->curr = o->currm1 = NULL;
 }

 void *
 llist_getNext(llist_t * o)
 {
 	llist_slink *f;
 	void *r;

 	if (o == NULL)
 		return (NULL);

 	/* check if we have any in the list */
 	if (o->last == NULL)
 		return (NULL);

 	/* ok save off some pointers */
 	f = o->last->next;
 	r = f->ent;
 	f->ent = NULL;

 	/* now is this the last one? */
 	if (f == o->last) {
 		/* yep, none left after this */
 		o->n2last = o->last = NULL;
 		o->curr = o->currm1 = NULL;
 	} else {
 		if (o->n2last == o->last->next) {
 			/*
 			 * Yes, Removing next to last one. We cheat here and
 			 * just move n2last to the last one.
 			 */
 			o->n2last = o->last;
 		}
 		o->last->next = f->next;
 		f->next = NULL;
 	}
 	/* FREE up the memory */
 	FREE(f);
 	f = NULL;
 	/* reduce number in */
 	o->cntIn--;
 	/* and out goes the stored entry */
 	return (r);
 }

 llist_slink *
 llist_getNextSlist(llist_t * o)
 {
 	llist_slink *f;

 	if (o == NULL)
 		return (NULL);

 	/* is there one to pull? */
 	if (o->last == NULL)
 		return (NULL);

 	f = o->last->next;
 	if (f == o->last) {
 		/* last one turn off the lights */
 		o->n2last = o->curr = o->currm1 = o->last = NULL;
 	} else {
 		if (o->last->next == o->n2last) {
 			/* cheat again */
 			o->n2last = o->last;
 		}
 		o->last->next = f->next;
 	}
 	f->next = NULL;
 	o->cntIn--;
 	return (f);
 }


 void *
 llist_get(llist_t * o)
 {
 	if (o == NULL)
 		return (NULL);

 	/* any in the list? */
 	if (o->last == NULL)
 		/* no */
 		return (NULL);

 	if (o->wrapFlag) {
 		/* we have wrapped.  we only return NULL once  at wrap. */
 		o->wrapFlag = 0;
 		/* setup so we will rewind to start */
 		o->curr = o->currm1 = NULL;
 		return (NULL);
 	}
 	if ((o->curr == NULL) || (o->currm1 == NULL)) {
 		/* rewind to start */
 		o->curr = o->last->next;
 		o->currm1 = o->last;
 		if (o->curr == o->last) {
 			/* only one in list so set the wrapFlag */
 			o->wrapFlag = 1;
 		}
 		return (o->curr->ent);
 	}
 	/* ok setup to return the next value */
 	o->currm1 = o->curr;
 	o->curr = o->curr->next;
 	if (o->curr == NULL) {
 		return (NULL);
 	}
 	if (o->curr == o->last) {
 		/* gotten all the way around so set the flag */
 		o->wrapFlag = 1;
 	}
 	return (o->curr->ent);
 }

 void *
 llist_getThis(llist_t * o)
 {
 	void *r;

 	if (o == NULL)
 		return (NULL);

 	/* some in list? */
 	if (o->last == NULL)
 		/* no */
 		return (NULL);

 	if ((o->curr == NULL) || (o->currm1 == NULL)) {
 		/* start at the beginning */
 		o->curr = o->last->next;
 		o->currm1 = o->last;
 	}
 	/* get off the entry to return */
 	r = o->curr->ent;
 	/* null it */
 	o->curr->ent = NULL;

 	if (o->currm1 == o->curr) {
 		/* only one item in list */
 		FREE(o->last);
 		o->n2last = o->curr = o->currm1 = o->last = NULL;
 	} else {
 		if (o->last == o->curr) {
 			/* reset to next to last one. */
 			o->last = o->currm1;
 			if ((o->cntIn - 1) > 1) {
 				llist_slink *temp;

 				/* Special case I must fix n2last */
 				for (temp = o->last->next; temp != o->last; temp = temp->next) {
 					/*
 					 * Hunt until we get temp->next is
 					 * last then we are at last -1.
 					 */
 					if (temp->next == o->last) {
 						o->n2last = temp;
 						break;
 					}
 				}
 			}
 		}
 		o->currm1->next = o->curr->next;
 		o->curr->next = NULL;
 		FREE(o->curr);
 		o->curr = o->currm1->next;
 	}
 	o->cntIn--;
 	return (r);
 }

 int
 llist_backUpOne(llist_t * o)
 {
 	llist_slink *temp;

 	if (o == NULL)
 		return (LIB_STATUS_BAD);

 	if (o->cntIn < 2) {
 		/* can't back up if there are not at least 2. */
 		return (LIB_STATUS_BAD);
 	}
 	for (temp = o->curr; temp->next != o->curr; temp = temp->next) {
 		/* move through list. */
 		if (temp->next == o->currm1) {
 			o->curr = o->currm1;
 			o->currm1 = temp;
 			return (LIB_STATUS_GOOD);
 		}
 	}
 	return (LIB_STATUS_BAD);
 }

 void *
 llist_replaceThis(llist_t * o, void *e)
 {
 	void *r;

 	if (o == NULL)
 		return (NULL);

 	/* Any in the list? */
 	if (o->last == NULL)
 		/* no */
 		return (NULL);

 	if ((o->curr == NULL) || (o->currm1 == NULL)) {
 		o->curr = o->last->next;
 		o->currm1 = o->last;
 	}
 	r = o->curr->ent;
 	o->curr->ent = e;
 	return (r);
 }

 llist_slink *
 llist_getThisSlist(llist_t * o)
 {
 	llist_slink *r;

 	/* any in list? */
 	if (o->last == NULL)
 		return (NULL);

 	/* setup the pointers as necessary */
 	if ((o->curr == NULL) || (o->currm1 == NULL)) {
 		o->curr = o->last->next;
 		o->currm1 = o->last;
 	}
 	r = o->curr;
 	if (o->currm1 == o->curr) {
 		/* only one item in list */
 		o->curr = o->currm1 = o->last = NULL;
 	} else {
 		if (o->last == o->curr) {
 			/* reset to next to last one. */
 			o->last = o->currm1;
 			if ((o->cntIn - 1) > 1) {
 				llist_slink *temp;

 				/* Special case I must fix n2last */
 				for (temp = o->last->next; temp != o->last; temp = temp->next) {
 					/*
 					 * Hunt until we get temp->next is
 					 * last then we are at last -1.
 					 */
 					if (temp->next == o->last) {
 						o->n2last = temp;
 						break;
 					}
 				}
 			}
 		}
 		o->currm1->next = o->curr->next;
 		o->curr->next = NULL;
 		o->curr = o->currm1->next;
 	}
 	o->cntIn--;
 	return (r);
 }

 void
 llist_reset(llist_t * o)
 {
 	if (o == NULL)
 		return;

 	o->curr = o->currm1 = NULL;
 	o->wrapFlag = 0;
 	return;
 }

 int
 llist_insertHere(llist_t * o, void *a)
 {
 	llist_slink *tmp;

 	if (o == NULL)
 		return (LIB_STATUS_BAD);

 	if (o->currm1) {
 		tmp = (llist_slink *) CALLOC(1, sizeof(llist_slink));
 		if (tmp == NULL) {
 			return (LIB_STATUS_BAD);
 		}
 		tmp->ent = a;
 		tmp->next = o->currm1->next;
 		if (o->currm1 == o->n2last) {
 			/* Put in right before last. */
 			o->n2last = tmp;
 		}
 		o->currm1->next = tmp;
 	} else {
 		/*
 		 * List is reset so we drop to a typical insert.
 		 */
 		return (llist_insert(o, a));
 	}
 	o->cntIn++;
 	return (LIB_STATUS_GOOD);
 }

 int
 llist_appendHere(llist_t * o, void *a)
 {
 	llist_slink *tmp;

 	if (o == NULL)
 		return (LIB_STATUS_BAD);

 	if (o->curr) {
 		if (o->curr == o->currm1) {
 			/*
 			 * special case for only one item on list just do a
 			 * append.
 			 */
 			return (llist_append(o, a));
 		} else if (o->curr == o->last) {
 			/*
 			 * special case where the pointers are set to the
 			 * last one so it degenerates to a simple append
 			 */
 			return (llist_append(o, a));
 		} else {
 			/*
 			 * ok the curr is out in the list somewhere. Append
 			 * at where we are.
 			 */
 			tmp = (llist_slink *) CALLOC(1, sizeof(struct llist_slink));
 			if (tmp == NULL) {
 				return (LIB_STATUS_BAD);
 			}
 			tmp->ent = a;
 			tmp->next = o->curr->next;
 			if (o->curr == o->n2last)
 				/* putting it after n2last. */
 				o->n2last = tmp;
 			o->curr->next = tmp;
 		}
 	} else {
 		/*
 		 * degenerate to an append if list as not been touched
 		 */
 		return (llist_append(o, a));

 	}
 	o->cntIn++;
 	return (LIB_STATUS_GOOD);
 }

 void
 llist_printCnt(llist_t * o)
 {
 	if (o == NULL)
 		return;

 	printf("On queue %d\n", o->cntIn);
 }

 void
 llist_printList(llist_t * o)
 {
 	llist_slink *ll, *pp;
 	int i;

 	if (o == NULL)
 		return;

 	if (o->last == NULL) {
 		printf("List is empty\n");
 		return;
 	} else {
 		printf("There are %d items on the list\n", o->cntIn);
 	}
 	ll = o->last->next;
 	i = 0;
 	do {
 		printf("%d:Me %p Entry %p Next->%p\n",
 		    i, ll, ll->ent, ll->next);
 		pp = ll->next;
 		ll = pp;
 		i++;
 	} while (ll != o->last);
 	printf("%d:Me %p Entry %p Next->%p\n",
 	    i, o->last, o->last->ent, o->last->next);
 	printf("List ends\n");
 }

 int
 llist_getToTheEnd(llist_t * o)
 {
 	if (o == NULL)
 		return (LIB_STATUS_BAD);

 	if (o->last == NULL)
 		return (0);
 	o->wrapFlag = 0;
 	o->curr = o->last;
 	if ((o->n2last == o->curr) && (o->cntIn > 1)) {
 		llist_slink *temp;

 		/* Special case I must fix n2last */
 		for (temp = o->last->next; temp != o->last; temp = temp->next) {
 			/*
 			 * Hunt until we get temp->next is last then we are
 			 * at last -1.
 			 */
 			if (temp->next == o->last) {
 				o->n2last = temp;
 				break;
 			}
 		}
 	}
 	o->currm1 = o->n2last;
 	return (1);
 }

 void *
 llist_lookLastOne(llist_t * o)
 {
 	if (o == NULL)
 		return (NULL);

 	if (o->last == NULL)
 		return (NULL);
 	return (o->last->ent);
 }

 void *
 llist_lookN2LastOne(llist_t * o)
 {
 	if (o == NULL)
 		return (NULL);

 	if (o->n2last == NULL)
 		return (NULL);
 	return (o->n2last->ent);
 }

 int
 llist_getCnt(llist_t * o)
 {
 	if (o == NULL)
 		return (0);

 	return o->cntIn;
 }
	/* $Header: /usr/sctpCVS/APPS/baselib/llist.c,v 1.3 2008-12-26 14:45:12 randall Exp $ */

	/*
	* Copyright (C) 2002 Cisco Systems Inc,
	* 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. Neither the name of the project nor the names of its contributors
	* may be used to endorse or promote products derived from this software
	* without specific prior written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
	* ANY EXPRESS 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 PROJECT OR 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.
	*/

	#include "llist.h"

	llist_t *
	llist_create()
	{
	llist_t *o;

	o = (llist_t *) CALLOC(1, sizeof(llist_t));
	if (o == NULL)
	return (NULL);
	o->curr = o->currm1 = NULL;
	o->cntIn = 0;
	o->n2last = o->last = NULL;
	o->wrapFlag = 0;
	return (o);
	}

	void
	llist_destroy(llist_t * o)
	{
	if (o == NULL)
	return;

	llist_clear(o);
	FREE(o);
	}

	int
	llist_append(llist_t * o, void *a)
	{
	llist_slink *tmp;

	if (o == NULL)
	return (LIB_STATUS_BAD);

	if (o->last) {
	/* entries in the list */
	o->n2last = o->last;
	tmp = (llist_slink *) CALLOC(1, sizeof(llist_slink));
	if (tmp == NULL) {
	return (LIB_STATUS_BAD);
	}
	tmp->ent = a;
	tmp->next = o->last->next;
	o->last->next = tmp;
	o->last = tmp;
	} else {
	/* no entires in the list */
	o->n2last = o->last = (llist_slink *) CALLOC(1, sizeof(llist_slink));
	if (o->last == NULL) {
	return (LIB_STATUS_BAD);
	}
	o->last->ent = a;
	o->last->next = NULL;
	o->last->next = o->last;
	}
	o->cntIn++;
	return (LIB_STATUS_GOOD);
	}

	int
	llist_appendslink(llist_t * o, llist_slink * a)
	{
	if (o == NULL)
	return (LIB_STATUS_BAD);

	if (a == NULL)
	/*
	* We don't allow a NULL llist_slink struct to be entered in
	* the list
	*/
	return (LIB_STATUS_BAD);

	if (o->last) {
	/* one or more entries in the list */
	o->n2last = o->last;
	a->next = o->last->next;
	o->last->next = a;
	o->last = a;
	} else {
	/* no entries in list. */
	o->n2last = o->last = a;
	o->last->next = o->last;
	}
	o->cntIn++;
	return (LIB_STATUS_GOOD);
	}

	int
	llist_insert(llist_t * o, void *a)
	{
	llist_slink *tmp;

	if (o == NULL)
	return (LIB_STATUS_BAD);

	if (o->last) {
	tmp = (llist_slink *) CALLOC(1, sizeof(llist_slink));
	if (tmp == NULL) {
	return (LIB_STATUS_BAD);
	}
	tmp->ent = a;
	tmp->next = o->last->next;
	o->last->next = tmp;
	} else {
	o->n2last = o->last = (llist_slink *) CALLOC(1, sizeof(llist_slink));
	if (o->last == NULL) {
	return (LIB_STATUS_BAD);
	}
	o->last->ent = a;
	o->last->next = NULL;
	o->last->next = o->last;
	}
	o->cntIn++;
	return (LIB_STATUS_GOOD);
	}

	void
	llist_clear(llist_t * o)
	{
	void *pp;

	if (o == NULL)
	return;

	while ((pp = llist_getNext(o)) != NULL) {
	pp = NULL;
	}
	o->n2last = o->last = NULL;
	o->curr = o->currm1 = NULL;
	}

	void *
	llist_getNext(llist_t * o)
	{
	llist_slink *f;
	void *r;

	if (o == NULL)
	return (NULL);

	/* check if we have any in the list */
	if (o->last == NULL)
	return (NULL);

	/* ok save off some pointers */
	f = o->last->next;
	r = f->ent;
	f->ent = NULL;

	/* now is this the last one? */
	if (f == o->last) {
	/* yep, none left after this */
	o->n2last = o->last = NULL;
	o->curr = o->currm1 = NULL;
	} else {
	if (o->n2last == o->last->next) {
	/*
	* Yes, Removing next to last one. We cheat here and
	* just move n2last to the last one.
	*/
	o->n2last = o->last;
	}
	o->last->next = f->next;
	f->next = NULL;
	}
	/* FREE up the memory */
	FREE(f);
	f = NULL;
	/* reduce number in */
	o->cntIn--;
	/* and out goes the stored entry */
	return (r);
	}

	llist_slink *
	llist_getNextSlist(llist_t * o)
	{
	llist_slink *f;

	if (o == NULL)
	return (NULL);

	/* is there one to pull? */
	if (o->last == NULL)
	return (NULL);

	f = o->last->next;
	if (f == o->last) {
	/* last one turn off the lights */
	o->n2last = o->curr = o->currm1 = o->last = NULL;
	} else {
	if (o->last->next == o->n2last) {
	/* cheat again */
	o->n2last = o->last;
	}
	o->last->next = f->next;
	}
	f->next = NULL;
	o->cntIn--;
	return (f);
	}


	void *
	llist_get(llist_t * o)
	{
	if (o == NULL)
	return (NULL);

	/* any in the list? */
	if (o->last == NULL)
	/* no */
	return (NULL);

	if (o->wrapFlag) {
	/* we have wrapped. we only return NULL once at wrap. */
	o->wrapFlag = 0;
	/* setup so we will rewind to start */
	o->curr = o->currm1 = NULL;
	return (NULL);
	}
	if ((o->curr == NULL) \|\| (o->currm1 == NULL)) {
	/* rewind to start */
	o->curr = o->last->next;
	o->currm1 = o->last;
	if (o->curr == o->last) {
	/* only one in list so set the wrapFlag */
	o->wrapFlag = 1;
	}
	return (o->curr->ent);
	}
	/* ok setup to return the next value */
	o->currm1 = o->curr;
	o->curr = o->curr->next;
	if (o->curr == NULL) {
	return (NULL);
	}
	if (o->curr == o->last) {
	/* gotten all the way around so set the flag */
	o->wrapFlag = 1;
	}
	return (o->curr->ent);
	}

	void *
	llist_getThis(llist_t * o)
	{
	void *r;

	if (o == NULL)
	return (NULL);

	/* some in list? */
	if (o->last == NULL)
	/* no */
	return (NULL);

	if ((o->curr == NULL) \|\| (o->currm1 == NULL)) {
	/* start at the beginning */
	o->curr = o->last->next;
	o->currm1 = o->last;
	}
	/* get off the entry to return */
	r = o->curr->ent;
	/* null it */
	o->curr->ent = NULL;

	if (o->currm1 == o->curr) {
	/* only one item in list */
	FREE(o->last);
	o->n2last = o->curr = o->currm1 = o->last = NULL;
	} else {
	if (o->last == o->curr) {
	/* reset to next to last one. */
	o->last = o->currm1;
	if ((o->cntIn - 1) > 1) {
	llist_slink *temp;

	/* Special case I must fix n2last */
	for (temp = o->last->next; temp != o->last; temp = temp->next) {
	/*
	* Hunt until we get temp->next is
	* last then we are at last -1.
	*/
	if (temp->next == o->last) {
	o->n2last = temp;
	break;
	}
	}
	}
	}
	o->currm1->next = o->curr->next;
	o->curr->next = NULL;
	FREE(o->curr);
	o->curr = o->currm1->next;
	}
	o->cntIn--;
	return (r);
	}

	int
	llist_backUpOne(llist_t * o)
	{
	llist_slink *temp;

	if (o == NULL)
	return (LIB_STATUS_BAD);

	if (o->cntIn < 2) {
	/* can't back up if there are not at least 2. */
	return (LIB_STATUS_BAD);
	}
	for (temp = o->curr; temp->next != o->curr; temp = temp->next) {
	/* move through list. */
	if (temp->next == o->currm1) {
	o->curr = o->currm1;
	o->currm1 = temp;
	return (LIB_STATUS_GOOD);
	}
	}
	return (LIB_STATUS_BAD);
	}

	void *
	llist_replaceThis(llist_t * o, void *e)
	{
	void *r;

	if (o == NULL)
	return (NULL);

	/* Any in the list? */
	if (o->last == NULL)
	/* no */
	return (NULL);

	if ((o->curr == NULL) \|\| (o->currm1 == NULL)) {
	o->curr = o->last->next;
	o->currm1 = o->last;
	}
	r = o->curr->ent;
	o->curr->ent = e;
	return (r);
	}

	llist_slink *
	llist_getThisSlist(llist_t * o)
	{
	llist_slink *r;

	/* any in list? */
	if (o->last == NULL)
	return (NULL);

	/* setup the pointers as necessary */
	if ((o->curr == NULL) \|\| (o->currm1 == NULL)) {
	o->curr = o->last->next;
	o->currm1 = o->last;
	}
	r = o->curr;
	if (o->currm1 == o->curr) {
	/* only one item in list */
	o->curr = o->currm1 = o->last = NULL;
	} else {
	if (o->last == o->curr) {
	/* reset to next to last one. */
	o->last = o->currm1;
	if ((o->cntIn - 1) > 1) {
	llist_slink *temp;

	/* Special case I must fix n2last */
	for (temp = o->last->next; temp != o->last; temp = temp->next) {
	/*
	* Hunt until we get temp->next is
	* last then we are at last -1.
	*/
	if (temp->next == o->last) {
	o->n2last = temp;
	break;
	}
	}
	}
	}
	o->currm1->next = o->curr->next;
	o->curr->next = NULL;
	o->curr = o->currm1->next;
	}
	o->cntIn--;
	return (r);
	}

	void
	llist_reset(llist_t * o)
	{
	if (o == NULL)
	return;

	o->curr = o->currm1 = NULL;
	o->wrapFlag = 0;
	return;
	}

	int
	llist_insertHere(llist_t * o, void *a)
	{
	llist_slink *tmp;

	if (o == NULL)
	return (LIB_STATUS_BAD);

	if (o->currm1) {
	tmp = (llist_slink *) CALLOC(1, sizeof(llist_slink));
	if (tmp == NULL) {
	return (LIB_STATUS_BAD);
	}
	tmp->ent = a;
	tmp->next = o->currm1->next;
	if (o->currm1 == o->n2last) {
	/* Put in right before last. */
	o->n2last = tmp;
	}
	o->currm1->next = tmp;
	} else {
	/*
	* List is reset so we drop to a typical insert.
	*/
	return (llist_insert(o, a));
	}
	o->cntIn++;
	return (LIB_STATUS_GOOD);
	}

	int
	llist_appendHere(llist_t * o, void *a)
	{
	llist_slink *tmp;

	if (o == NULL)
	return (LIB_STATUS_BAD);

	if (o->curr) {
	if (o->curr == o->currm1) {
	/*
	* special case for only one item on list just do a
	* append.
	*/
	return (llist_append(o, a));
	} else if (o->curr == o->last) {
	/*
	* special case where the pointers are set to the
	* last one so it degenerates to a simple append
	*/
	return (llist_append(o, a));
	} else {
	/*
	* ok the curr is out in the list somewhere. Append
	* at where we are.
	*/
	tmp = (llist_slink *) CALLOC(1, sizeof(struct llist_slink));
	if (tmp == NULL) {
	return (LIB_STATUS_BAD);
	}
	tmp->ent = a;
	tmp->next = o->curr->next;
	if (o->curr == o->n2last)
	/* putting it after n2last. */
	o->n2last = tmp;
	o->curr->next = tmp;
	}
	} else {
	/*
	* degenerate to an append if list as not been touched
	*/
	return (llist_append(o, a));

	}
	o->cntIn++;
	return (LIB_STATUS_GOOD);
	}

	void
	llist_printCnt(llist_t * o)
	{
	if (o == NULL)
	return;

	printf("On queue %d\n", o->cntIn);
	}

	void
	llist_printList(llist_t * o)
	{
	llist_slink ll, pp;
	int i;

	if (o == NULL)
	return;

	if (o->last == NULL) {
	printf("List is empty\n");
	return;
	} else {
	printf("There are %d items on the list\n", o->cntIn);
	}
	ll = o->last->next;
	i = 0;
	do {
	printf("%d:Me %p Entry %p Next->%p\n",
	i, ll, ll->ent, ll->next);
	pp = ll->next;
	ll = pp;
	i++;
	} while (ll != o->last);
	printf("%d:Me %p Entry %p Next->%p\n",
	i, o->last, o->last->ent, o->last->next);
	printf("List ends\n");
	}

	int
	llist_getToTheEnd(llist_t * o)
	{
	if (o == NULL)
	return (LIB_STATUS_BAD);

	if (o->last == NULL)
	return (0);
	o->wrapFlag = 0;
	o->curr = o->last;
	if ((o->n2last == o->curr) && (o->cntIn > 1)) {
	llist_slink *temp;

	/* Special case I must fix n2last */
	for (temp = o->last->next; temp != o->last; temp = temp->next) {
	/*
	* Hunt until we get temp->next is last then we are
	* at last -1.
	*/
	if (temp->next == o->last) {
	o->n2last = temp;
	break;
	}
	}
	}
	o->currm1 = o->n2last;
	return (1);
	}

	void *
	llist_lookLastOne(llist_t * o)
	{
	if (o == NULL)
	return (NULL);

	if (o->last == NULL)
	return (NULL);
	return (o->last->ent);
	}

	void *
	llist_lookN2LastOne(llist_t * o)
	{
	if (o == NULL)
	return (NULL);

	if (o->n2last == NULL)
	return (NULL);
	return (o->n2last->ent);
	}

	int
	llist_getCnt(llist_t * o)
	{
	if (o == NULL)
	return (0);

	return o->cntIn;
	}