/* This file is part of GNUnet (C) 2004, 2005, 2006, 2008, 2009 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 2, 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_dht_service.h * @brief API to the DHT service * @author Christian Grothoff */ #ifndef GNUNET_DHT_SERVICE_H #define GNUNET_DHT_SERVICE_H #include "gnunet_util_lib.h" #ifdef __cplusplus extern "C" { #if 0 /* keep Emacsens' auto-indent happy */ } #endif #endif /** * Connection to the DHT service. */ struct GNUNET_DHT_Handle; /** * Initialize the connection with the DHT service. * * @param cfg configuration to use * @param sched scheduler to use * @param ht_len size of the internal hash table to use for * processing multiple GET/FIND requests in parallel * @return NULL on error */ struct GNUNET_DHT_Handle * GNUNET_DHT_connect (struct GNUNET_SCHEDULER_Handle *sched, const struct GNUNET_CONFIGURATION_Handle *cfg, unsigned int ht_len); /** * Shutdown connection with the DHT service. * * @param h connection to shut down */ void GNUNET_DHT_disconnect (struct GNUNET_DHT_Handle *h); /** * Perform a PUT operation on the DHT identified by 'table' storing * a binding of 'key' to 'value'. The peer does not have to be part * of the table (if so, we will attempt to locate a peer that is!) * * @param h handle to DHT service * @param key the key to store under * @param type type of the value * @param size number of bytes in data; must be less than 64k * @param data the data to store * @param exp desired expiration time for the value * @param timeout when to abort with an error if we fail to get * a confirmation for the PUT from the local DHT service * @param cont continuation to call when done; * reason will be TIMEOUT on error, * reason will be PREREQ_DONE on success * @param cont_cls closure for cont */ void GNUNET_DHT_put (struct GNUNET_DHT_Handle *h, const GNUNET_HashCode * key, uint32_t type, uint32_t size, const char *data, struct GNUNET_TIME_Absolute exp, struct GNUNET_TIME_Relative timeout, GNUNET_SCHEDULER_Task cont, void *cont_cls); /** * Handle to control a GET operation. */ struct GNUNET_DHT_GetHandle; /** * Iterator called on each result obtained for a GET * operation. * * @param cls closure * @param exp when will this value expire * @param key key of the result * @param type type of the result * @param size number of bytes in data * @param data pointer to the result data */ typedef void (*GNUNET_DHT_Iterator)(void *cls, struct GNUNET_TIME_Absolute exp, const GNUNET_HashCode * key, uint32_t type, uint32_t size, const void *data); /** * Perform an asynchronous GET operation on the DHT identified. * * @param h handle to the DHT service * @param type expected type of the response object * @param key the key to look up * @param iter function to call on each result * @param iter_cls closure for iter * @return handle to stop the async get, NULL on error */ struct GNUNET_DHT_GetHandle * GNUNET_DHT_get_start (struct GNUNET_DHT_Handle *h, uint32_t type, const GNUNET_HashCode * key, GNUNET_DHT_Iterator iter, void *iter_cls); /** * Stop async DHT-get. Frees associated resources. * * @param get_handle GET operation to stop. */ void GNUNET_DHT_get_stop (struct GNUNET_DHT_GetHandle *get_handle); /** * Iterator called on each result obtained from a FIND_PEER * operation * * @param cls closure * @param peer a peer that was located * @param reply response generated by the peer (for example, a HELLO); or NULL */ typedef void (*GNUNET_DHT_ReplyProcessor)(void *cls, const struct GNUNET_PeerIdentity *peer, const struct GNUNET_MessageHeader *reply); /** * Options for routing. */ enum GNUNET_DHT_RouteOption { /** * Default. Do nothing special. */ GNUNET_DHT_RO_NONE = 0, /** * Each peer along the way should look at 'enc' (otherwise * only the k-peers closest to the key should look at it). */ GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE = 1 }; /** * Perform an asynchronous FIND_PEER operation on the DHT. * * @param handle handle to the DHT service * @param key the key to look up * @param desired_replication_level how many peers should ultimately receive * this message (advisory only, target may be too high for the * given DHT or not hit exactly). * @param options options for routing * @param enc send the encapsulated message to a peer close to the key * @param iter function to call on each result, NULL if no replies are expected * @param iter_cls closure for iter * @param timeout when to abort with an error if we fail to get * a confirmation for the PUT from the local DHT service * @param cont continuation to call when done; * reason will be TIMEOUT on error, * reason will be PREREQ_DONE on success * @param cont_cls closure for cont * @return handle to stop the request */ struct GNUNET_DHT_FindPeerHandle * GNUNET_DHT_route_start (struct GNUNET_DHT_Handle *handle, const GNUNET_HashCode *key, unsigned int desired_replication_level, enum GNUNET_DHT_RouteOption options, const struct GNUNET_MessageHeader *enc, struct GNUNET_TIME_Relative timeout, GNUNET_DHT_ReplyProcessor iter, void *iter_cls, GNUNET_SCHEDULER_Task cont, void *cont_cls); void GNUNET_DHT_route_stop (struct GNUNET_DHT_FindPeerHandle *fph); #if 0 /* keep Emacsens' auto-indent happy */ { #endif #ifdef __cplusplus } #endif #endif /* gnunet_dht_service.h */