/* GLIB - Library of useful routines for C programming

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

 * Portions copyright (c) 2006 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"

typedef struct _GCacheNode  GCacheNode;

struct _GCacheNode

{

  /* A reference counted node */

  gpointer value;

  gint ref_count;

};

struct _GCache

{

  /* Called to create a value from a key */

  GCacheNewFunc value_new_func;

  /* Called to destroy a value */

  GCacheDestroyFunc value_destroy_func;

  /* Called to duplicate a key */

  GCacheDupFunc key_dup_func;

  /* Called to destroy a key */

  GCacheDestroyFunc key_destroy_func;

  /* Associates keys with nodes */

  GHashTable *key_table;

  /* Associates nodes with keys */

  GHashTable *value_table;

};

static inline GCacheNode*

g_cache_node_new (gpointer value)

{

  GCacheNode *node = g_slice_new (GCacheNode);

  node->value = value;

  node->ref_count = 1;

  return node;

}

static inline void

g_cache_node_destroy (GCacheNode *node)

{

  g_slice_free (GCacheNode, node);

}

EXPORT_C GCache*

g_cache_new (GCacheNewFunc      value_new_func,

	     GCacheDestroyFunc  value_destroy_func,

	     GCacheDupFunc      key_dup_func,

	     GCacheDestroyFunc  key_destroy_func,

	     GHashFunc          hash_key_func,

	     GHashFunc          hash_value_func,

	     GEqualFunc         key_equal_func)

{

  GCache *cache;

  g_return_val_if_fail (value_new_func != NULL, NULL);

  g_return_val_if_fail (value_destroy_func != NULL, NULL);

  g_return_val_if_fail (key_dup_func != NULL, NULL);

  g_return_val_if_fail (key_destroy_func != NULL, NULL);

  g_return_val_if_fail (hash_key_func != NULL, NULL);

  g_return_val_if_fail (hash_value_func != NULL, NULL);

  g_return_val_if_fail (key_equal_func != NULL, NULL);

  cache = g_slice_new (GCache);

  cache->value_new_func = value_new_func;

  cache->value_destroy_func = value_destroy_func;

  cache->key_dup_func = key_dup_func;

  cache->key_destroy_func = key_destroy_func;

  cache->key_table = g_hash_table_new (hash_key_func, key_equal_func);

  cache->value_table = g_hash_table_new (hash_value_func, NULL);

  return cache;

}

EXPORT_C void

g_cache_destroy (GCache *cache)

{

  g_return_if_fail (cache != NULL);

  g_hash_table_destroy (cache->key_table);

  g_hash_table_destroy (cache->value_table);

  g_slice_free (GCache, cache);

}

EXPORT_C gpointer

g_cache_insert (GCache   *cache,

		gpointer  key)

{

  GCacheNode *node;

  gpointer value;

  g_return_val_if_fail (cache != NULL, NULL);

  node = g_hash_table_lookup (cache->key_table, key);

  if (node)

    {

      node->ref_count += 1;

      return node->value;

    }

  key = (* cache->key_dup_func) (key);

  value = (* cache->value_new_func) (key);

  node = g_cache_node_new (value);

  g_hash_table_insert (cache->key_table, key, node);

  g_hash_table_insert (cache->value_table, value, key);

  return node->value;

}

EXPORT_C void

g_cache_remove (GCache        *cache,

		gconstpointer  value)

{

  GCacheNode *node;

  gpointer key;

  g_return_if_fail (cache != NULL);

  key = g_hash_table_lookup (cache->value_table, value);

  node = g_hash_table_lookup (cache->key_table, key);

  g_return_if_fail (node != NULL);

  node->ref_count -= 1;

  if (node->ref_count == 0)

    {

      g_hash_table_remove (cache->value_table, value);

      g_hash_table_remove (cache->key_table, key);

      (* cache->key_destroy_func) (key);

      (* cache->value_destroy_func) (node->value);

      g_cache_node_destroy (node);

    }

}

EXPORT_C void

g_cache_key_foreach (GCache   *cache,

		     GHFunc    func,

		     gpointer  user_data)

{

  g_return_if_fail (cache != NULL);

  g_return_if_fail (func != NULL);

  g_hash_table_foreach (cache->value_table, func, user_data);

}

EXPORT_C void

g_cache_value_foreach (GCache   *cache,

		       GHFunc    func,

		       gpointer  user_data)

{

  g_return_if_fail (cache != NULL);

  g_return_if_fail (func != NULL);

  g_hash_table_foreach (cache->key_table, func, user_data);

}

#define __G_CACHE_C__

#include "galiasdef.c"