/** BEGIN COPYRIGHT BLOCK
 * 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; version 2 of the License.
 * 
 * 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., 59 Temple
 * Place, Suite 330, Boston, MA 02111-1307 USA.
 * 
 * In addition, as a special exception, Red Hat, Inc. gives You the additional
 * right to link the code of this Program with code not covered under the GNU
 * General Public License ("Non-GPL Code") and to distribute linked combinations
 * including the two, subject to the limitations in this paragraph. Non-GPL Code
 * permitted under this exception must only link to the code of this Program
 * through those well defined interfaces identified in the file named EXCEPTION
 * found in the source code files (the "Approved Interfaces"). The files of
 * Non-GPL Code may instantiate templates or use macros or inline functions from
 * the Approved Interfaces without causing the resulting work to be covered by
 * the GNU General Public License. Only Red Hat, Inc. may make changes or
 * additions to the list of Approved Interfaces. You must obey the GNU General
 * Public License in all respects for all of the Program code and other code used
 * in conjunction with the Program except the Non-GPL Code covered by this
 * exception. If you modify this file, you may extend this exception to your
 * version of the file, but you are not obligated to do so. If you do not wish to
 * provide this exception without modification, you must delete this exception
 * statement from your version and license this file solely under the GPL without
 * exception. 
 * 
 * 
 * Copyright (C) 2001 Sun Microsystems, Inc. Used by permission.
 * Copyright (C) 2005 Red Hat, Inc.
 * All rights reserved.
 * END COPYRIGHT BLOCK **/

#ifdef HAVE_CONFIG_H
#  include <config.h>
#endif

/* DataList access functions */
#define INIT_ALLOC		8
#define ALLOC_INCREMENT	4

#include "slap.h"

DataList* dl_new ()
{
	return (DataList*)slapi_ch_malloc (sizeof (DataList));
}
void dl_free (DataList **dl)
{
	slapi_ch_free ((void**) dl);
}

void dl_init (DataList *dl, int init_alloc)
{
	PR_ASSERT (dl);

	memset (dl, 0, sizeof (*dl));

	if (init_alloc <= 0)
		dl->alloc_count = INIT_ALLOC;
	else
		dl->alloc_count = init_alloc;

	dl->elements = (void**)slapi_ch_calloc (dl->alloc_count, sizeof (void*));	
}

void dl_cleanup (DataList *dl, FREEFN freefn)
{
	PR_ASSERT (dl);

	if (freefn && dl->elements)
	{
		int i;

		for (i = 0; i < dl->element_count; i++)
		{
			freefn (&(dl->elements[i]));
		}
	}

	if (dl->elements)
	{
		slapi_ch_free ((void**)&dl->elements);
	}

	memset (dl, 0, sizeof (*dl));
}

/* index == 1 :  insert first */
void dl_add_index (DataList *dl, void *element, int index)
{
	int i = 0;

	PR_ASSERT (dl);
	PR_ASSERT (element);

	if (dl->element_count == dl->alloc_count)
	{
		dl->alloc_count += ALLOC_INCREMENT;
		dl->elements = (void**)slapi_ch_realloc ((char*)dl->elements, dl->alloc_count * sizeof (void*));
	}

	dl->element_count ++;

    for (i = dl->element_count-1; i >= index; i--)
    {
		dl->elements[i] = dl->elements[i-1];
    }
	if ( dl->element_count < index )
	{
		/* Means that we are adding the first element */
		dl->elements[0] = element;
	}
	else
	{
		dl->elements[i] = element;
	}
}

void dl_add (DataList *dl, void *element)
{
	PR_ASSERT (dl);
	PR_ASSERT (element);

	if (dl->element_count == dl->alloc_count)
	{
		dl->alloc_count += ALLOC_INCREMENT;
		dl->elements = (void**)slapi_ch_realloc ((char*)dl->elements, dl->alloc_count * sizeof (void*));
	}

	dl->elements[dl->element_count] = element;
	dl->element_count ++;
}

void *dl_get_first (const DataList *dl, int *cookie)
{
	PR_ASSERT (dl);
	PR_ASSERT (cookie);

	if (dl->element_count == 0)
		return NULL;

	*cookie = 1;
	return dl->elements[0];
}

void *dl_get_next (const DataList *dl, int *cookie)
{
	PR_ASSERT (dl);
	PR_ASSERT (cookie && *cookie > 0);

	if (*cookie >= dl->element_count)
		return NULL;

	return dl->elements[(*cookie)++];
}

void *dl_get_prev (const DataList *dl, int *cookie)
{
  PR_ASSERT (dl);
  PR_ASSERT (cookie && *cookie > 0);

  if (*cookie < 0)
      return NULL;
  if (*cookie > 0)
      (*cookie)--;

  return dl->elements[*cookie];
}

void *dl_replace(const DataList *dl, const void *elementOld, void *elementNew, CMPFN cmpfn, FREEFN freefn)
{
	int i;
	void *save;

    PR_ASSERT (dl);
    PR_ASSERT (elementOld);
    PR_ASSERT (elementNew);
    PR_ASSERT (cmpfn);
 
    for (i = 0; i < dl->element_count; i++)
    {
        if (cmpfn (dl->elements[i], elementOld) == 0)
        {
            /* if we have destructor - free the data; otherwise, return it to the client */
            if (freefn)
            {
                freefn (&dl->elements[i]);
                save = NULL;
            }
            else
                save = dl->elements[i];
 
			dl->elements[i] = elementNew;
 
            return save;
        }
    }

	return NULL;	
}

void *dl_get (const DataList *dl, const void *element, CMPFN cmpfn)
{
	int i;

	PR_ASSERT (dl);
	PR_ASSERT (element);
	PR_ASSERT (cmpfn);

	for (i = 0; i < dl->element_count; i++)
	{
		if (cmpfn (dl->elements[i], element) == 0)
		{
			return dl->elements[i];
		}
	}

	return NULL;
}

void *dl_delete (DataList *dl, const void *element, CMPFN cmpfn, FREEFN freefn)
{
	int i;
	void *save;

	PR_ASSERT (dl);
	PR_ASSERT (element);
	PR_ASSERT (cmpfn);

	for (i = 0; i < dl->element_count; i++)
	{
		if (cmpfn (dl->elements[i], element) == 0)
		{	
			/* if we have destructor - free the data; otherwise, return it to the client */
			if (freefn)
			{
				freefn (&dl->elements[i]);
				save = NULL;
			}
			else
				save = dl->elements[i];

			if (i != dl->element_count - 1)
			{
				memcpy (&dl->elements[i], &dl->elements[i+1], (dl->element_count - i - 1) * sizeof (void*));
			}
		
			dl->element_count --;

			return save;
		}
	}

	return NULL;
}

int dl_get_count (const DataList *dl)
{
	PR_ASSERT (dl);

	return dl->element_count;
}