/*
**  Written by David Gerdes  US Army Construction Engineering Research Lab
**  	April 1992
**  Copyright 1992 USA-CERL   All rights reserved.
**
****************************************************************************
 *
 * MODULE:       LINKED LIST MEMORY MANAGER
 *
 * AUTHOR(S):    David Gerdes 1992, US Army Construction Engineering Research Lab
 *
 * PURPOSE:      Outputs a raster map layer showing the cumulative cost
 *               of moving between different geographic locations on an
 *               input raster map layer whose cell category values
 *               represent cost.
 *
 * COPYRIGHT:    (C) 1999, 2006 by the GRASS Development Team
 *
 *               This program is free software under the GNU General Public
 *               License (>=v2). Read the file COPYING that comes with GRASS
 *               for details.
 *
 ***************************************************************************/
#include <stdlib.h>
#include <grass/linkm.h>

static int link_chunk_size = 100;
static int link_exit_flag = 0;

void link_set_chunk_size (int size)
{
    link_chunk_size = size;
}

void link_exit_on_error (int flag)
{
    link_exit_flag = flag;
}

struct link_head *link_init (int size)
{
    
    struct link_head *Head;

    if (NULL == (Head = (struct link_head *) malloc (sizeof (struct link_head))))
	return NULL;

    if (NULL == (Head->ptr_array = (VOID_T **) malloc (sizeof (VOID_T *) * PTR_CNT)))
    {
	free (Head);
	return NULL;
    }

    Head->max_ptr = 0;
    Head->Unused = NULL;
    Head->alloced = PTR_CNT;
    Head->unit_size = size < sizeof (VOID_T *) ? sizeof (VOID_T *) : size;
    Head->chunk_size = link_chunk_size;
    Head->exit_flag = link_exit_flag;

    return Head;
}

void link_cleanup (struct link_head *Head)
{
    register int i;

    if (Head == NULL)
	return;
    
    if (Head->ptr_array)
    {
	for (i = 0 ; i < Head->max_ptr ; i++)
	    if (Head->ptr_array[i] != NULL)
		free (Head->ptr_array[i]);
	free (Head->ptr_array);
	free (Head);
    }
}
