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diff --git a/src/libstrongswan/utils/hashtable.c b/src/libstrongswan/utils/hashtable.c
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+++ b/src/libstrongswan/utils/hashtable.c
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+/*
+ * Copyright (C) 2008 Tobias Brunner
+ * Hochschule fuer Technik Rapperswil
+ *
+ * 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; either version 2 of the License, or (at your
+ * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * 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.
+ *
+ * $Id: hashtable.c 4812 2008-12-17 09:56:05Z tobias $
+ */
+
+#include <utils/linked_list.h>
+
+#include "hashtable.h"
+
+/** The maximum capacity of the hash table (MUST be a power of 2) */
+#define MAX_CAPACITY (1 << 30)
+
+typedef struct pair_t pair_t;
+
+/**
+ * This pair holds a pointer to the key and value it represents.
+ */
+struct pair_t {
+	/**
+	 * Key of a hash table item.
+	 */
+	void *key;
+	
+	/**
+	 * Value of a hash table item.
+	 */
+	void *value;
+	
+	/**
+	 * Cached hash (used in case of a resize).
+	 */
+	u_int hash;
+};
+
+/**
+ * Creates an empty pair object.
+ */
+pair_t *pair_create(void *key, void *value, u_int hash)
+{
+	pair_t *this = malloc_thing(pair_t);
+	
+	this->key = key;
+	this->value = value;
+	this->hash = hash;
+	
+	return this;
+}
+
+typedef struct private_hashtable_t private_hashtable_t;
+
+/**
+ * Private data of a hashtable_t object.
+ *
+ */
+struct private_hashtable_t {
+	/**
+	 * Public part of hash table.
+	 */
+	hashtable_t public;
+	
+	/**
+	 * The number of items in the hash table. 
+	 */
+	u_int count;
+	
+	/**
+	 * The current capacity of the hash table (always a power of 2).
+	 */
+	u_int capacity;
+	
+	/**
+	 * The current mask to calculate the row index (capacity - 1). 
+	 */
+	u_int mask;
+	
+	/**
+	 * The load factor.
+	 */
+	float load_factor;
+	
+	/**
+	 * The actual table.
+	 */
+	linked_list_t **table;
+	
+	/**
+	 * The hashing function.
+	 */
+	hashtable_hash_t hash;
+	
+	/**
+	 * The equality function.
+	 */
+	hashtable_equals_t equals;
+};
+
+typedef struct private_enumerator_t private_enumerator_t;
+
+/**
+ * hash table enumerator implementation
+ */
+struct private_enumerator_t {
+
+	/**
+	 * implements enumerator interface
+	 */
+	enumerator_t enumerator;
+	
+	/**
+	 * associated hash table
+	 */
+	private_hashtable_t *table;
+	
+	/**
+	 * current row index
+	 */
+	u_int row;
+	
+	/**
+	 * enumerator for the current row
+	 */
+	enumerator_t *current;
+};
+
+/**
+ * Compare a pair in a list with the given key.
+ */
+static inline bool pair_equals(pair_t *pair, private_hashtable_t *this, void *key)
+{
+	return this->equals(key, pair->key);
+}
+
+/**
+ * This function returns the next-highest power of two for the given number.
+ * The algorithm works by setting all bits on the right-hand side of the most
+ * significant 1 to 1 and then increments the whole number so it rolls over
+ * to the nearest power of two. Note: returns 0 for n == 0
+ */
+static u_int get_nearest_powerof2(u_int n)
+{
+	u_int i;
+	--n;
+	for (i = 1; i < sizeof(u_int) * 8; i <<= 1)
+	{
+		n |= n >> i;
+	}
+	return ++n;
+}
+
+/**
+ * Init hash table parameters
+ */
+static void init_hashtable(private_hashtable_t *this, u_int capacity)
+{
+	capacity = max(1, min(capacity, MAX_CAPACITY));
+	this->capacity = get_nearest_powerof2(capacity);
+	this->mask = this->capacity - 1;
+	this->load_factor = 0.75;
+	
+	this->table = calloc(this->capacity, sizeof(linked_list_t*));
+}
+
+/**
+ * Double the size of the hash table and rehash all the elements.
+ */
+static void rehash(private_hashtable_t *this)
+{
+	u_int row;
+	u_int old_capacity = this->capacity;
+	linked_list_t **old_table = this->table;
+	
+	if (old_capacity >= MAX_CAPACITY)
+	{
+		return;
+	}
+	
+	init_hashtable(this, old_capacity << 1);
+	
+	for (row = 0; row < old_capacity; ++row)
+	{
+		linked_list_t *list;
+		if ((list = old_table[row]) != NULL)
+		{
+			pair_t *pair;
+			enumerator_t *enumerator = list->create_enumerator(list);
+			while (enumerator->enumerate(enumerator, &pair))
+			{
+				linked_list_t *new_list;
+				u_int new_row = pair->hash & this->mask;
+				list->remove_at(list, enumerator);
+				if ((new_list = this->table[new_row]) == NULL)
+				{
+					new_list = this->table[new_row] = linked_list_create();
+				}
+				new_list->insert_last(new_list, pair);
+			}
+			enumerator->destroy(enumerator);
+			list->destroy(list);
+		}
+	}
+	free(old_table);
+}
+
+/**
+ * Implementation of hashtable_t.put
+ */
+static void *put(private_hashtable_t *this, void *key, void *value)
+{
+	linked_list_t *list;
+	void *old_value = NULL;
+	u_int hash = this->hash(key);
+	u_int row = hash & this->mask;
+	
+	if ((list = this->table[row]) != NULL)
+	{
+		pair_t *pair;
+		enumerator_t *enumerator = list->create_enumerator(list);
+		while (enumerator->enumerate(enumerator, &pair))
+		{
+			if (pair_equals(pair, this, key))
+			{
+				old_value = pair->value;
+				pair->value = value;
+				break;
+			}
+		}
+		enumerator->destroy(enumerator);
+	}
+	else
+	{
+		list = this->table[row] = linked_list_create();
+	}
+	
+	if (!old_value)
+	{
+		list->insert_last(list, pair_create(key, value, hash));
+		this->count++;
+	}
+	
+	if (this->count >= this->capacity * this->load_factor)
+	{
+		rehash(this);
+	}
+	
+	return old_value;
+}
+	
+/**
+ * Implementation of hashtable_t.get  
+ */
+static void *get(private_hashtable_t *this, void *key)
+{
+	void *value = NULL;
+	linked_list_t *list;
+	u_int row = this->hash(key) & this->mask;
+	
+	if ((list = this->table[row]) != NULL)
+	{
+		pair_t *pair;
+		if (list->find_first(list, (linked_list_match_t)pair_equals,
+				(void**)&pair, this, key) == SUCCESS)
+		{
+			value = pair->value;
+		}
+	}
+	
+	return value;
+}
+	
+/**
+ * Implementation of hashtable_t.remove
+ */
+static void *remove(private_hashtable_t *this, void *key)
+{
+	void *value = NULL;
+	linked_list_t *list;
+	u_int row = this->hash(key) & this->mask;	
+	
+	if ((list = this->table[row]) != NULL)
+	{
+		pair_t *pair;
+		enumerator_t *enumerator = list->create_enumerator(list);
+		while (enumerator->enumerate(enumerator, &pair))
+		{
+			if (pair_equals(pair, this, key))
+			{
+				list->remove_at(list, enumerator);
+				value = pair->value;
+				this->count--;
+				free(pair);
+				break;
+			}
+		}
+		enumerator->destroy(enumerator);
+	}
+	
+	return value;
+}
+	
+/**
+ * Implementation of hashtable_t.get_count
+ */
+static u_int get_count(private_hashtable_t *this)
+{
+	return this->count;
+}
+
+/**
+ * Implementation of private_enumerator_t.enumerator.enumerate.
+ */
+static bool enumerate(private_enumerator_t *this, void **key, void **value)
+{
+	while (this->row < this->table->capacity)
+	{
+		if (this->current)
+		{
+			pair_t *pair;
+			
+			if (this->current->enumerate(this->current, &pair))
+			{
+				if (key)
+				{
+					*key = pair->key;
+				}
+				if (value)
+				{
+					*value = pair->value;
+				}
+				return TRUE;
+			}
+			this->current->destroy(this->current);
+			this->current = NULL;
+		}
+		else
+		{
+			linked_list_t *list;
+			
+			if ((list = this->table->table[this->row]) != NULL)
+			{
+				this->current = list->create_enumerator(list);
+				continue;
+			}
+		}
+		this->row++;
+	}
+	return FALSE;
+}
+
+/**
+ * Implementation of private_enumerator_t.enumerator.destroy.
+ */
+static void enumerator_destroy(private_enumerator_t *this)
+{
+	if (this->current)
+	{
+		this->current->destroy(this->current);
+	}
+	free(this);
+}
+
+/**
+ * Implementation of hashtable_t.create_enumerator.
+ */
+static enumerator_t* create_enumerator(private_hashtable_t *this)
+{
+	private_enumerator_t *enumerator = malloc_thing(private_enumerator_t);
+	
+	enumerator->enumerator.enumerate = (void*)enumerate;
+	enumerator->enumerator.destroy = (void*)enumerator_destroy;
+	enumerator->table = this;
+	enumerator->row = 0;
+	enumerator->current = NULL;
+	
+	return &enumerator->enumerator;
+}
+	
+/**
+ * Implementation of hashtable_t.destroy
+ */
+static void destroy(private_hashtable_t *this)
+{
+	u_int row;
+	for (row = 0; row < this->capacity; ++row)
+	{
+		linked_list_t *list;
+		if ((list = this->table[row]) != NULL)
+		{
+			list->destroy_function(list, free);
+		}
+	}
+	free(this->table);
+	free(this);
+}
+
+/*
+ * Described in header.
+ */
+hashtable_t *hashtable_create(hashtable_hash_t hash, hashtable_equals_t equals,
+							  u_int capacity)
+{
+	private_hashtable_t *this = malloc_thing(private_hashtable_t);
+
+	this->public.put = (void*(*)(hashtable_t*,void*,void*))put;
+	this->public.get = (void*(*)(hashtable_t*,void*))get; 
+	this->public.remove = (void*(*)(hashtable_t*,void*))remove;
+	this->public.get_count = (u_int(*)(hashtable_t*))get_count;
+	this->public.create_enumerator = (enumerator_t*(*)(hashtable_t*))create_enumerator;
+	this->public.destroy = (void(*)(hashtable_t*))destroy;
+	
+	this->count = 0;
+	this->capacity = 0;
+	this->mask = 0;
+	this->load_factor = 0;
+	this->table = NULL;
+	this->hash = hash;
+	this->equals = equals;
+	
+	init_hashtable(this, capacity);
+	
+	return &this->public;
+}