server/src/util/lists.c

/*
Copyright (c) 1998-2010, Enno Rehling <enno@eressea.de>
                         Katja Zedel <katze@felidae.kn-bremen.de
                         Christian Schlittchen <corwin@amber.kn-bremen.de>

Permission to use, copy, modify, and/or distribute this software for any
purpose with or without fee is hereby granted, provided that the above
copyright notice and this permission notice appear in all copies.

THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
**/

#include <stdlib.h>
#include <assert.h>

#include <platform.h>
#include "lists.h"

void
addlist(void *l1, void *p1)
{

	/* add entry p to the end of list l */

	void_list **l;
	void_list *p, *q;

	l = (void_list **)l1;
	p = (void_list *)p1;
	assert(p->next == 0);

	if (*l) {
		for (q = *l; q->next; q = q->next)
			assert(q);
		q->next = p;
	} else
		*l = p;
}

void
choplist(void * a, void * b)
{
	void_list **l = (void_list**)a, *p = (void_list*)b;
	/* remove entry p from list l - when called, a pointer to p must be
	 * kept in order to use (and free) p; if omitted, this will be a
	 * memory leak */

	void_list **q;

	for (q = l; *q; q = &((*q)->next)) {
		if (*q == p) {
			*q = p->next;
			p->next = 0;
			break;
		}
	}
}

void
translist(void *l1, void *l2, void *p)
{

	/* remove entry p from list l1 and add it at the end of list l2 */

	choplist(l1, p);
	addlist(l2, p);
}

void
insertlist(void_list ** l, void_list * p)
{

	/* insert entry p at the beginning of list l */

	p->next = *l;
	*l = p;

}

void
removelist(void *l, void *p)
{

	/* remove entry p from list l; free p */

	choplist(l, p);
	free(p);
}

void
freelist(void *p1)
{

	/* remove all entries following and including entry p from a listlist */

	void_list *p, *p2;

	p = (void_list *)p1;

	while (p) {
		p2 = p->next;
		free(p);
		p = p2;
	}
}

unsigned int
listlen(void *l)
{

	/* count entries p in list l */

	unsigned int i;
	void_list *p;

	for (p = (void_list *)l, i = 0; p; p = p->next, i++);
	return i;
}

/* Hilfsfunktion, um das Debugging zu erleichtern.  Statt print
 * (cast)foo->next->next->next->next nur noch
 * print (cast)listelem(foo, 3) */

void *
listelem(void *l, int n)
{
	int i=0;

	while(i < n && l != NULL) {
			l = ((void_list *)l)->next;
			i++;
	}

	return l;
}