cache_hashtable.h

/* 
 * Copyright 2010 CurveDNS Project. All rights reserved.
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 * Redistribution and use in source and binary forms, with or without modification, are
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 *       of conditions and the following disclaimer in the documentation and/or other materials
 *       provided with the distribution.
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/*
 * $Id$ 
 * $Author$
 * $Date$
 * $Revision$
 */

#ifndef CACHE_HASHTABLE_H_
#define CACHE_HASHTABLE_H_

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>

#include <ev.h>
#include "crypto_box_curve25519xsalsa20poly1305.h"
#include "debug.h"

// The cache mechanism isn't really general, it is focused
// on the public key client -> shared key fetching.

#define	CACHE_KEY_SIZE		crypto_box_curve25519xsalsa20poly1305_PUBLICKEYBYTES
#define	CACHE_VALUE_SIZE	crypto_box_curve25519xsalsa20poly1305_BEFORENMBYTES

struct cache_table {
	struct cache_entry **buckets;
	struct cache_entry *entries;
	struct cache_entry *headunused;
	struct cache_entry *headused, *lastused;
	int nrbuckets, nrentries, nrused;
};

struct cache_entry {
	struct cache_entry *next, *prev, *nexttable;
	uint8_t key[CACHE_KEY_SIZE];
	uint8_t value[CACHE_VALUE_SIZE];
};

extern struct cache_table *dnscurve_cache;

extern void cache_stats(struct cache_table *);
extern struct cache_table *cache_init(int, int);
extern struct cache_entry *cache_get(struct cache_table *, uint8_t *);
extern struct cache_entry *cache_set(struct cache_table *, uint8_t *, uint8_t *);
extern int cache_empty(struct cache_table *);
extern int cache_destroy(struct cache_table *);

#endif /* CACHE_H_ */