/*
     This file is part of GNUnet
     (C) 2012, 2013 Christian Grothoff (and other contributing authors)

     GNUnet 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 3, or (at your
     option) any later version.

     GNUnet 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.

     You should have received a copy of the GNU General Public License
     along with GNUnet; see the file COPYING.  If not, write to the
     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
     Boston, MA 02111-1307, USA.
*/

/**
 * @file include/gnunet_peerstore_plugin.h
 * @brief plugin API for the peerstore database backend
 * @author Omar Tarabai
 */
#ifndef GNUNET_PEERSTORE_PLUGIN_H
#define GNUNET_PEERSTORE_PLUGIN_H

#include "gnunet_util_lib.h"
#include "gnunet_peerstore_service.h"

#ifdef __cplusplus
extern "C"
{
#if 0                           /* keep Emacsens' auto-indent happy */
}
#endif
#endif


/**
 * @brief struct returned by the initialization function of the plugin
 */
struct GNUNET_PEERSTORE_PluginFunctions
{

  /**
   * Closure to pass to all plugin functions.
   */
  void *cls;

  /**
   * Store a record in the peerstore.
   * Key is the combination of sub system and peer identity.
   * One key can store multiple values.
   *
   * @param cls closure (internal context for the plugin)
   * @param sub_system name of the GNUnet sub system responsible
   * @param peer peer identity
   * @param value value to be stored
   * @param size size of value to be stored
   * @return #GNUNET_OK on success, else #GNUNET_SYSERR
   */
  int
  (*store_record) (void *cls,
      const char *sub_system,
      const struct GNUNET_PeerIdentity *peer,
      const char *key,
      const void *value,
      size_t size,
      struct GNUNET_TIME_Absolute expiry,
      enum GNUNET_PEERSTORE_StoreOption options);

  /**
   * Iterate over the records given an optional peer id
   * and/or key.
   *
   * @param cls closure (internal context for the plugin)
   * @param sub_system name of sub system
   * @param peer Peer identity (can be NULL)
   * @param key entry key string (can be NULL)
   * @param iter function to call with the result
   * @param iter_cls closure for @a iter
   * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
   */
  int
  (*iterate_records) (void *cls,
      const char *sub_system,
      const struct GNUNET_PeerIdentity *peer,
      const char *key,
      GNUNET_PEERSTORE_Processor iter, void *iter_cls);

  /**
   * Delete expired records (expiry < now)
   *
   * @param cls closure (internal context for the plugin)
   * @param now time to use as reference
   * @return number of records deleted
   */
  int
  (*expire_records) (void *cls,
      struct GNUNET_TIME_Absolute now);

};


#if 0                           /* keep Emacsens' auto-indent happy */
{
#endif
#ifdef __cplusplus
}
#endif

/* end of gnunet_peerstore_plugin.h */
#endif