/*

  idcache.h

  Author: Pekka Riikonen <priikone@poseidon.pspt.fi>

  Copyright (C) 2000 Pekka Riikonen

  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.
  
  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.

*/

#ifndef IDCACHE_H
#define IDCACHE_H

/* 
   Silc ID Cache Entry object.

   This is one entry in the SILC ID Cache system. Contents of this is
   allocated outside the ID cache system, however, all the fields are 
   filled with ID cache utility functions. The ID cache system does not
   allocate any of these fields nor free them.

   unsigned char *data
   uint32 data_len;

      The data that is usually used to find the data from the cache.
      For example for Client ID's this is nickname.

   SilcIdType type

      Type of the ID.

   void *id

      The actual ID.

   uint32 expire

      Time when this cache entry expires.  This is normal time() value
      plus the validity.  Cache entry has expired if current time is
      more than value in this field.  If this value is zero (0) the
      entry never expires.

   void *context

      Any caller specified context.

*/
typedef struct {
  unsigned char *data;
  uint32 data_len;
  SilcIdType type;
  void *id;
  uint32 expire;
  void *context;
} *SilcIDCacheEntry;

/* Forward declaration for SILC ID Cache object. */
typedef struct SilcIDCacheStruct *SilcIDCache;

/* Forward declaration for ID Cache List */
typedef struct SilcIDCacheListStruct *SilcIDCacheList;

/* Destructor callback that is called when an cache entry expires or is
   purged from the ID cache. The application must not free cache entry
   because the library will do it automatically. The appliation, however,
   is responsible of freeing any data in the entry. */
typedef void (*SilcIDCacheDestructor)(SilcIDCache cache,
				      SilcIDCacheEntry entry);

#define SILC_ID_CACHE_ANY ((void *)1)

#define SILC_ID_CACHE_EXPIRE 3600
#define SILC_ID_CACHE_EXPIRE_DEF (time(NULL) + SILC_ID_CACHE_EXPIRE)

/* Prototypes */
SilcIDCache silc_idcache_alloc(uint32 count,
			       SilcIDCacheDestructor destructor);
void silc_idcache_free(SilcIDCache cache);
void silc_idcache_sort_by_data(SilcIDCache cache);
int silc_idcache_find_by_data(SilcIDCache cache, unsigned char *data, 
			      SilcIDCacheList *ret);
int silc_idcache_find_by_data_one(SilcIDCache cache, unsigned char *data,
				  SilcIDCacheEntry *ret);
int silc_idcache_find_by_data_loose(SilcIDCache cache, unsigned char *data, 
				    SilcIDCacheList *ret);
int silc_idcache_find_by_id(SilcIDCache cache, void *id, SilcIdType type,
			    SilcIDCacheList *ret);
int silc_idcache_find_by_id_one(SilcIDCache cache, void *id, SilcIdType type, 
				SilcIDCacheEntry *ret);
int silc_idcache_find_by_context(SilcIDCache cache, void *context, 
				 SilcIDCacheEntry *ret);
int silc_idcache_add(SilcIDCache cache, unsigned char *data, 
		     uint32 data_len, SilcIdType id_type, void *id, 
		     void *context, int sort, int expire);
int silc_idcache_del(SilcIDCache cache, SilcIDCacheEntry old);
int silc_idcache_del_by_data(SilcIDCache cache, unsigned char *data);
int silc_idcache_del_by_id(SilcIDCache cache, SilcIdType type, void *id);
int silc_idcache_del_all(SilcIDCache cache);
int silc_idcache_purge(SilcIDCache cache);
int silc_idcache_purge_by_context(SilcIDCache cache, void *context);
int silc_idcache_list_count(SilcIDCacheList list);
int silc_idcache_list_first(SilcIDCacheList list, SilcIDCacheEntry *ret);
int silc_idcache_list_next(SilcIDCacheList list, SilcIDCacheEntry *ret);
void silc_idcache_list_free(SilcIDCacheList list);

#endif