iterator.c
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/* GNU Mailutils -- a suite of utilities for electronic mail
Copyright (C) 1999, 2000 Free Software Foundation, Inc.
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
This library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <errno.h>
#include <stdlib.h>
#include <list0.h>
#include <iterator0.h>
int
iterator_create (iterator_t *piterator, list_t list)
{
iterator_t iterator;
if (piterator == NULL || list == NULL)
return EINVAL;
iterator = calloc (sizeof (*iterator), 1);
if (iterator == NULL)
return ENOMEM;
iterator->list = list;
iterator->cur = NULL;
iterator->next = list->itr;
list->itr = iterator;
iterator->is_advanced = 0;
*piterator = iterator;
return 0;
}
void
iterator_destroy (iterator_t *piterator)
{
iterator_t itr, prev;
if (!piterator || !*piterator)
return;
for (itr = (*piterator)->list->itr, prev = NULL;
itr;
prev = itr, itr = itr->next)
if (*piterator == itr)
break;
if (itr)
{
if (prev)
prev->next = itr->next;
else
itr->list->itr = itr->next;
free(itr);
*piterator = NULL;
}
}
int
iterator_first (iterator_t iterator)
{
iterator->cur = iterator->list->head.next;
iterator->is_advanced = 0;
return 0;
}
int
iterator_next (iterator_t iterator)
{
if (!iterator->is_advanced)
iterator->cur = iterator->cur->next;
iterator->is_advanced = 0;
return 0;
}
int
iterator_current (iterator_t iterator, void **pitem)
{
if (!iterator->cur)
return ENOENT;
*pitem = iterator->cur->item;
return 0;
}
int
iterator_is_done (iterator_t iterator)
{
if (iterator == NULL)
return 1;
return iterator->cur == NULL || iterator->cur == &iterator->list->head;
}
int
iterator_get_list (iterator_t iterator, list_t *plist)
{
if (!iterator)
return EINVAL;
*plist = iterator->list;
return NULL;
}
void
iterator_advance (iterator_t iterator, struct list_data *e)
{
for (; iterator; iterator = iterator->next)
{
if (iterator->cur == e)
{
iterator->cur = e->next;
iterator->is_advanced++;
}
}
}