/* GLIB - Library of useful routines for C programming

 * Copyright (C) 1995-1997  Peter Mattis, Spencer Kimball and Josh MacDonald

 * Portions copyright (c) 2006-2009 Nokia Corporation.  All rights reserved.

 *

 * 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.

 */

/*

 * Modified by the GLib Team and others 1997-2000.  See the AUTHORS

 * file for a list of people on the GLib Team.  See the ChangeLog

 * files for a list of changes.  These files are distributed with

 * GLib at ftp://ftp.gtk.org/pub/gtk/. 

 */

/* 

 * MT safe

 */

#include "config.h"

#include "glib.h"

#include "galias.h"

EXPORT_C void g_slist_push_allocator (gpointer dummy) { /* present for binary compat only */ }

EXPORT_C void g_slist_pop_allocator  (void)           { /* present for binary compat only */ }

#define _g_slist_alloc0()       g_slice_new0 (GSList)

#define _g_slist_alloc()        g_slice_new (GSList)

#define _g_slist_free1(slist)   g_slice_free (GSList, slist)

EXPORT_C GSList*

g_slist_alloc (void)

{

  return _g_slist_alloc0 ();

}

/**

 * g_slist_free:

 * @list: a #GSList

 *

 * Frees all of the memory used by a #GSList.

 * The freed elements are returned to the slice allocator.

 */

EXPORT_C void

g_slist_free (GSList *list)

{

  g_slice_free_chain (GSList, list, next);

}

/**

 * g_slist_free_1:

 * @list: a #GSList element

 * 

 * Frees one #GSList element.

 * It is usually used after g_slist_remove_link().

 */

EXPORT_C void

g_slist_free_1 (GSList *list)

{

  _g_slist_free1 (list);

}

/**

 * g_slist_append:

 * @list: a #GSList

 * @data: the data for the new element

 *

 * Adds a new element on to the end of the list.

 *

 * <note><para>

 * The return value is the new start of the list, which may 

 * have changed, so make sure you store the new value.

 * </para></note>

 *

 * <note><para>

 * Note that g_slist_append() has to traverse the entire list 

 * to find the end, which is inefficient when adding multiple 

 * elements. A common idiom to avoid the inefficiency is to prepend 

 * the elements and reverse the list when all elements have been added.

 * </para></note>

 *

 * |[

 * /* Notice that these are initialized to the empty list. */

 * GSList *list = NULL, *number_list = NULL;

 *

 * /* This is a list of strings. */

 * list = g_slist_append (list, "first");

 * list = g_slist_append (list, "second");

 *

 * /* This is a list of integers. */

 * number_list = g_slist_append (number_list, GINT_TO_POINTER (27));

 * number_list = g_slist_append (number_list, GINT_TO_POINTER (14));

 * ]|

 *

 * Returns: the new start of the #GSList

 */

EXPORT_C GSList*

g_slist_append (GSList   *list,

		gpointer  data)

{

  GSList *new_list;

  GSList *last;

  new_list = _g_slist_alloc ();

  new_list->data = data;

  new_list->next = NULL;

  if (list)

    {

      last = g_slist_last (list);

      /* g_assert (last != NULL); */

      last->next = new_list;

      return list;

    }

  else

    return new_list;

}

/**

 * g_slist_prepend:

 * @list: a #GSList

 * @data: the data for the new element

 *

 * Adds a new element on to the start of the list.

 *

 * <note><para>

 * The return value is the new start of the list, which 

 * may have changed, so make sure you store the new value.

 * </para></note>

 *

 * |[

 * /* Notice that it is initialized to the empty list. */

 * GSList *list = NULL;

 * list = g_slist_prepend (list, "last");

 * list = g_slist_prepend (list, "first");

 * ]|

 *

 * Returns: the new start of the #GSList

 */

EXPORT_C GSList*

g_slist_prepend (GSList   *list,

		 gpointer  data)

{

  GSList *new_list;

  new_list = _g_slist_alloc ();

  new_list->data = data;

  new_list->next = list;

  return new_list;

}

/**

 * g_slist_insert:

 * @list: a #GSList

 * @data: the data for the new element

 * @position: the position to insert the element. 

 *     If this is negative, or is larger than the number 

 *     of elements in the list, the new element is added on

 *     to the end of the list.

 *

 * Inserts a new element into the list at the given position.

 *

 * Returns: the new start of the #GSList

 */

EXPORT_C GSList*

g_slist_insert (GSList   *list,

		gpointer  data,

		gint      position)

{

  GSList *prev_list;

  GSList *tmp_list;

  GSList *new_list;

  if (position < 0)

    return g_slist_append (list, data);

  else if (position == 0)

    return g_slist_prepend (list, data);

  new_list = _g_slist_alloc ();

  new_list->data = data;

  if (!list)

    {

      new_list->next = NULL;

      return new_list;

    }

  prev_list = NULL;

  tmp_list = list;

  while ((position-- > 0) && tmp_list)

    {

      prev_list = tmp_list;

      tmp_list = tmp_list->next;

    }

  if (prev_list)

    {

      new_list->next = prev_list->next;

      prev_list->next = new_list;

    }

  else

    {

      new_list->next = list;

      list = new_list;

    }

  return list;

}

/**

 * g_slist_insert_before:

 * @slist: a #GSList

 * @sibling: node to insert @data before

 * @data: data to put in the newly-inserted node

 *

 * Inserts a node before @sibling containing @data. 

 * 

 * Returns: the new head of the list.

 */

EXPORT_C GSList*

g_slist_insert_before (GSList  *slist,

		       GSList  *sibling,

		       gpointer data)

{

  if (!slist)

    {

      slist = _g_slist_alloc ();

      slist->data = data;

      slist->next = NULL;

      g_return_val_if_fail (sibling == NULL, slist);

      return slist;

    }

  else

    {

      GSList *node, *last = NULL;

      for (node = slist; node; last = node, node = last->next)

	if (node == sibling)

	  break;

      if (!last)

	{

	  node = _g_slist_alloc ();

	  node->data = data;

	  node->next = slist;

	  return node;

	}

      else

	{

	  node = _g_slist_alloc ();

	  node->data = data;

	  node->next = last->next;

	  last->next = node;

	  return slist;

	}

    }

}

/**

 * g_slist_concat:

 * @list1: a #GSList

 * @list2: the #GSList to add to the end of the first #GSList

 *

 * Adds the second #GSList onto the end of the first #GSList.

 * Note that the elements of the second #GSList are not copied.

 * They are used directly.

 *

 * Returns: the start of the new #GSList

 */

EXPORT_C GSList *

g_slist_concat (GSList *list1, GSList *list2)

{

  if (list2)

    {

      if (list1)

	g_slist_last (list1)->next = list2;

      else

	list1 = list2;

    }

  return list1;

}

/**

 * g_slist_remove:

 * @list: a #GSList

 * @data: the data of the element to remove

 *

 * Removes an element from a #GSList.

 * If two elements contain the same data, only the first is removed.

 * If none of the elements contain the data, the #GSList is unchanged.

 *

 * Returns: the new start of the #GSList

 */

EXPORT_C GSList*

g_slist_remove (GSList        *list,

		gconstpointer  data)

{

  GSList *tmp, *prev = NULL;

  tmp = list;

  while (tmp)

    {

      if (tmp->data == data)

	{

	  if (prev)

	    prev->next = tmp->next;

	  else

	    list = tmp->next;

	  g_slist_free_1 (tmp);

	  break;

	}

      prev = tmp;

      tmp = prev->next;

    }

  return list;

}

/**

 * g_slist_remove_all:

 * @list: a #GSList

 * @data: data to remove

 *

 * Removes all list nodes with data equal to @data. 

 * Returns the new head of the list. Contrast with 

 * g_slist_remove() which removes only the first node 

 * matching the given data.

 *

 * Returns: new head of @list

 */

EXPORT_C GSList*

g_slist_remove_all (GSList        *list,

		    gconstpointer  data)

{

  GSList *tmp, *prev = NULL;

  tmp = list;

  while (tmp)

    {

      if (tmp->data == data)

	{

	  GSList *next = tmp->next;

	  if (prev)

	    prev->next = next;

	  else

	    list = next;

	  g_slist_free_1 (tmp);

	  tmp = next;

	}

      else

	{

	  prev = tmp;

	  tmp = prev->next;

	}

    }

  return list;

}

static inline GSList*

_g_slist_remove_link (GSList *list,

		      GSList *link)

{

  GSList *tmp;

  GSList *prev;

  prev = NULL;

  tmp = list;

  while (tmp)

    {

      if (tmp == link)

	{

	  if (prev)

	    prev->next = tmp->next;

	  if (list == tmp)

	    list = list->next;

	  tmp->next = NULL;

	  break;

	}

      prev = tmp;

      tmp = tmp->next;

    }

  return list;

}

/**

 * g_slist_remove_link:

 * @list: a #GSList

 * @link_: an element in the #GSList

 *

 * Removes an element from a #GSList, without 

 * freeing the element. The removed element's next 

 * link is set to %NULL, so that it becomes a

 * self-contained list with one element.

 *

 * Returns: the new start of the #GSList, without the element

 */

EXPORT_C GSList* 

g_slist_remove_link (GSList *list,

		     GSList *link_)

{

  return _g_slist_remove_link (list, link_);

}

/**

 * g_slist_delete_link:

 * @list: a #GSList

 * @link_: node to delete

 *

 * Removes the node link_ from the list and frees it. 

 * Compare this to g_slist_remove_link() which removes the node 

 * without freeing it.

 *

 * Returns: the new head of @list

 */

EXPORT_C GSList*

g_slist_delete_link (GSList *list,

		     GSList *link_)

{

  list = _g_slist_remove_link (list, link_);

  _g_slist_free1 (link_);

  return list;

}

/**

 * g_slist_copy:

 * @list: a #GSList

 * 

 * Copies a #GSList.

 * 

 * <note><para>

 * Note that this is a "shallow" copy. If the list elements 

 * consist of pointers to data, the pointers are copied but 

 * the actual data isn't.

 * </para></note>

 *

 * Returns: a copy of @list

 */

EXPORT_C GSList*

g_slist_copy (GSList *list)

{

  GSList *new_list = NULL;

  if (list)

    {

      GSList *last;

      new_list = _g_slist_alloc ();

      new_list->data = list->data;

      last = new_list;

      list = list->next;

      while (list)

	{

	  last->next = _g_slist_alloc ();

	  last = last->next;

	  last->data = list->data;

	  list = list->next;

	}

      last->next = NULL;

    }

  return new_list;

}

/**

 * g_slist_reverse:

 * @list: a #GSList

 *

 * Reverses a #GSList.

 *

 * Returns: the start of the reversed #GSList

 */

EXPORT_C GSList*

g_slist_reverse (GSList *list)

{

  GSList *prev = NULL;

  while (list)

    {

      GSList *next = list->next;

      list->next = prev;

      prev = list;

      list = next;

    }

  return prev;

}

/**

 * g_slist_nth:

 * @list: a #GSList

 * @n: the position of the element, counting from 0

 *

 * Gets the element at the given position in a #GSList.

 *

 * Returns: the element, or %NULL if the position is off 

 *     the end of the #GSList

 */

EXPORT_C GSList*