tinc/lib/list.c
2000-11-22 23:09:38 +00:00

143 lines
3.1 KiB
C

/*
list.c -- functions to deal with double linked lists
Copyright (C) 2000 Ivo Timmermans <itimmermans@bigfoot.com>
2000 Guus Sliepen <guus@sliepen.warande.net>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
$Id: list.c,v 1.1.2.6 2000/11/22 23:09:38 guus Exp $
*/
#include "config.h"
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <list.h>
#include <xalloc.h>
#include <system.h>
/*
list_new
Initialize a new list.
*/
list_t *list_new(void)
{
list_t *list;
list = xmalloc_and_zero(sizeof(list_t));
return list;
}
/*
list_delete
Delete the element pointed to by idx from the list.
*/
void list_delete(list_t *list, list_node_t *idx)
{
if(!list || !idx)
return;
if(list->callbacks->delete != NULL)
if(list->callbacks->delete(idx->data))
syslog(LOG_WARNING, _("List callback[delete] failed for %08lx - freeing anyway"), idx->data);
free(idx->data);
if(idx->prev == NULL)
/* First element in list */
{
list->head = idx->next;
}
if(idx->next == NULL)
/* Last element in list */
{
list->tail = idx->prev;
}
if(idx->prev != NULL && idx->next != NULL)
/* Neither first nor last element */
{
idx->prev->next = idx->next;
idx->next->prev = idx->prev;
}
if(list->head == NULL)
list->tail = NULL;
else
if(list->tail == NULL)
list->head = NULL;
free(idx);
}
/*
list_forall_nodes
Call function() on each element in the list. If this function
returns non-zero, the element will be removed from the list.
*/
void list_forall_nodes(list_t *list, int (*function)(void *data))
{
list_node_t *p, *next;
int res;
if(!list) /* no list given */
return;
if(!function) /* no function given */
return;
if(!list->head) /* list is empty */
return;
for(p = list->head; p != NULL; p = next)
{
next = p->next;
res = function(p->data);
if(res != 0)
list_delete(list, p);
}
}
/*
list_destroy
Free all datastructures contained in this list. It uses the delete
callback for this list to free each element.
*/
void list_destroy(list_t *list)
{
if(!list)
return;
/* list_destroy_nodes(list); */
free(list);
}
/*
list_append
Append a new node to the list that points to data.
*/
void list_append(list_t *list, void *data)
{
list_node_t *n;
n = xmalloc_and_zero(sizeof(list_node_t));
n->data = data;
n->prev = list->tail;
if(list->tail)
list->tail->next = n;
list->tail = n;
}