2 This file is part of GNUnet.
3 (C) 2009, 2010 Christian Grothoff (and other contributing authors)
5 GNUnet is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 3, or (at your
8 option) any later version.
10 GNUnet is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
22 * @file dht/dht_api_get_put.c
23 * @brief library to perform DHT gets and puts
24 * @author Christian Grothoff
25 * @author Nathan Evans
29 #include "gnunet_constants.h"
30 #include "gnunet_arm_service.h"
31 #include "gnunet_protocols.h"
32 #include "gnunet_util_lib.h"
33 #include "gnunet_dht_service.h"
38 * Perform a PUT operation storing data in the DHT.
40 * @param handle handle to DHT service
41 * @param key the key to store under
42 * @param desired_replication_level estimate of how many
43 * nearest peers this request should reach
44 * @param options routing options for this message
45 * @param type type of the value
46 * @param size number of bytes in data; must be less than 64k
47 * @param data the data to store
48 * @param exp desired expiration time for the value
49 * @param timeout how long to wait for transmission of this request
50 * @param cont continuation to call when done (transmitting request to service)
51 * @param cont_cls closure for cont
52 * @return GNUNET_YES if put message is queued for transmission
55 GNUNET_DHT_put (struct GNUNET_DHT_Handle *handle,
56 const GNUNET_HashCode * key,
57 uint32_t desired_replication_level,
58 enum GNUNET_DHT_RouteOption options,
59 enum GNUNET_BLOCK_Type type,
62 struct GNUNET_TIME_Absolute exp,
63 struct GNUNET_TIME_Relative timeout,
64 GNUNET_SCHEDULER_Task cont, void *cont_cls)
66 char buf[GNUNET_SERVER_MAX_MESSAGE_SIZE];
67 struct GNUNET_DHT_PutMessage *put_msg;
69 if (size >= sizeof (buf) - sizeof (struct GNUNET_DHT_PutMessage))
74 put_msg = (struct GNUNET_DHT_PutMessage *) buf;
75 put_msg->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_PUT);
76 put_msg->header.size = htons (sizeof (struct GNUNET_DHT_PutMessage) + size);
77 put_msg->type = htonl ((uint32_t) type);
78 put_msg->expiration = GNUNET_TIME_absolute_hton (exp);
79 memcpy (&put_msg[1], data, size);
80 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
81 "Starting route for %u byte `%s' message of type %u \n",
82 (unsigned int) (sizeof (struct GNUNET_DHT_PutMessage) + size),
85 GNUNET_DHT_route_start (handle,
87 desired_replication_level, options,
89 timeout, NULL, NULL, cont, cont_cls));
95 * Handle to control a get operation.
97 struct GNUNET_DHT_GetHandle
100 * Handle to the actual route operation for the get
102 struct GNUNET_DHT_RouteHandle *route_handle;
105 * Iterator to call on data receipt
107 GNUNET_DHT_GetIterator iter;
110 * Closure for the iterator callback
119 * Iterator called on each result obtained from a generic route
122 * @param cls the 'struct GNUNET_DHT_GetHandle'
123 * @param key key that was used
124 * @param outgoing_path path of the message from this peer
126 * @param reply response
129 get_reply_iterator (void *cls,
130 const GNUNET_HashCode * key,
131 const struct GNUNET_PeerIdentity *const *outgoing_path,
132 const struct GNUNET_MessageHeader *reply)
134 struct GNUNET_DHT_GetHandle *get_handle = cls;
135 const struct GNUNET_DHT_GetResultMessage *result;
136 const struct GNUNET_PeerIdentity **put_path;
139 const struct GNUNET_PeerIdentity *pos;
141 uint16_t put_path_length;
144 if (ntohs (reply->type) != GNUNET_MESSAGE_TYPE_DHT_GET_RESULT)
150 GNUNET_assert (ntohs (reply->size) >=
151 sizeof (struct GNUNET_DHT_GetResultMessage));
152 result = (const struct GNUNET_DHT_GetResultMessage *) reply;
155 put_path_length = ntohs (result->put_path_length);
156 if (put_path_length > 0)
159 ntohs (result->header.size) -
160 (put_path_length * sizeof (struct GNUNET_PeerIdentity)) -
161 sizeof (struct GNUNET_DHT_GetResultMessage);
162 path_offset = (char *) &result[1];
163 //GNUNET_log(GNUNET_ERROR_TYPE_WARNING, "In get_reply_iterator, result->header.size is %d, put_path_length %d, offset is %d, data_size is %d\n", ntohs(result->header.size), put_path_length, ntohs(result->header.size) - (put_path_length * sizeof(struct GNUNET_PeerIdentity)), data_size);
164 path_offset += data_size;
165 pos = (const struct GNUNET_PeerIdentity *) path_offset;
166 //GNUNET_log(GNUNET_ERROR_TYPE_WARNING, "Found put peer %s\n", GNUNET_i2s((const struct GNUNET_PeerIdentity *)path_offset));
168 GNUNET_malloc ((put_path_length +
169 1) * sizeof (struct GNUNET_PeerIdentity *));
170 for (i = 0; i < put_path_length; i++)
175 put_path[put_path_length] = NULL;
178 payload = ntohs (reply->size) - sizeof (struct GNUNET_DHT_GetResultMessage);
179 get_handle->iter (get_handle->iter_cls,
180 GNUNET_TIME_absolute_ntoh (result->expiration),
183 put_path, ntohs (result->type), payload, &result[1]);
184 GNUNET_free_non_null (put_path);
190 * Perform an asynchronous GET operation on the DHT identified. See
191 * also "GNUNET_BLOCK_evaluate".
193 * @param handle handle to the DHT service
194 * @param timeout how long to wait for transmission of this request to the service
195 * @param type expected type of the response object
196 * @param key the key to look up
197 * @param desired_replication_level estimate of how many
198 nearest peers this request should reach
199 * @param options routing options for this message
200 * @param bf bloom filter associated with query (can be NULL)
201 * @param bf_mutator mutation value for bf
202 * @param xquery extended query data (can be NULL, depending on type)
203 * @param xquery_size number of bytes in xquery
204 * @param iter function to call on each result
205 * @param iter_cls closure for iter
207 * @return handle to stop the async get
209 struct GNUNET_DHT_GetHandle *
210 GNUNET_DHT_get_start (struct GNUNET_DHT_Handle *handle,
211 struct GNUNET_TIME_Relative timeout,
212 enum GNUNET_BLOCK_Type type,
213 const GNUNET_HashCode * key,
214 uint32_t desired_replication_level,
215 enum GNUNET_DHT_RouteOption options,
216 const struct GNUNET_CONTAINER_BloomFilter *bf,
220 GNUNET_DHT_GetIterator iter, void *iter_cls)
222 struct GNUNET_DHT_GetHandle *get_handle;
223 char buf[GNUNET_SERVER_MAX_MESSAGE_SIZE - 1];
224 struct GNUNET_DHT_GetMessage *get_msg;
227 bf_size = GNUNET_CONTAINER_bloomfilter_get_size (bf);
229 sizeof (struct GNUNET_DHT_GetMessage) + xquery_size + bf_size) ||
230 (sizeof (buf) <= bf_size))
235 get_handle = GNUNET_malloc (sizeof (struct GNUNET_DHT_GetHandle));
236 get_handle->iter = iter;
237 get_handle->iter_cls = iter_cls;
238 get_msg = (struct GNUNET_DHT_GetMessage *) buf;
239 get_msg->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_GET);
240 get_msg->header.size = htons (sizeof (struct GNUNET_DHT_GetMessage) +
241 xquery_size + bf_size);
242 get_msg->type = htonl ((uint32_t) type);
243 get_msg->bf_mutator = bf_mutator;
244 get_msg->xquery_size = htons ((uint16_t) xquery_size);
245 get_msg->bf_size = htons (bf_size);
247 memcpy (&buf[sizeof (struct GNUNET_DHT_GetMessage)], xquery, xquery_size);
249 GNUNET_assert (xquery_size == 0);
250 (void) GNUNET_CONTAINER_bloomfilter_get_raw_data (bf,
253 GNUNET_DHT_GetMessage)
256 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
257 "Starting route for %u byte `%s' message\n",
258 (unsigned int) (sizeof (struct GNUNET_DHT_GetMessage) +
259 xquery_size + bf_size), "GET");
260 get_handle->route_handle =
261 GNUNET_DHT_route_start (handle, key, desired_replication_level, options,
262 &get_msg->header, timeout, &get_reply_iterator,
263 get_handle, NULL, NULL);
264 GNUNET_break (NULL != get_handle->route_handle);
270 * Stop async DHT-get.
272 * @param get_handle handle to the GET operation to stop
274 * On return get_handle will no longer be valid, caller
275 * must not use again!!!
278 GNUNET_DHT_get_stop (struct GNUNET_DHT_GetHandle *get_handle)
280 GNUNET_DHT_route_stop (get_handle->route_handle);
281 GNUNET_free (get_handle);
285 /* end of dht_api_get_put.c */