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22 * @file fs/gnunet-service-fs_pr.h
23 * @brief API to handle pending requests
24 * @author Christian Grothoff
26 #ifndef GNUNET_SERVICE_FS_PR_H
27 #define GNUNET_SERVICE_FS_PR_H
29 #include "gnunet-service-fs.h"
33 * Options for pending requests (bits to be ORed).
35 enum GSF_PendingRequestOptions
39 * No special options (P2P-default).
44 * Request must only be processed locally.
46 GSF_PRO_LOCAL_ONLY = 1,
49 * Request must only be forwarded (no routing)
51 GSF_PRO_FORWARD_ONLY = 2,
54 * Request persists indefinitely (no expiration).
56 GSF_PRO_REQUEST_NEVER_EXPIRES = 4,
59 * Request is allowed to refresh bloomfilter and change mingle value.
61 GSF_PRO_BLOOMFILTER_FULL_REFRESH = 8,
64 * Request priority is allowed to be exceeded.
66 GSF_PRO_PRIORITY_UNLIMITED = 16,
69 * Option mask for typical local requests.
71 GSF_PRO_LOCAL_REQUEST =
72 (GSF_PRO_BLOOMFILTER_FULL_REFRESH | GSF_PRO_PRIORITY_UNLIMITED | GSF_PRO_REQUEST_NEVER_EXPIRES)
77 * Public data (in the sense of not encapsulated within
78 * 'gnunet-service-fs_pr', not in the sense of network-wide
79 * known) associated with each pending request.
81 struct GSF_PendingRequestData
85 * Primary query hash for this request.
87 struct GNUNET_HashCode query;
90 * Namespace to query, only set if the type is SBLOCK.
91 * Allocated after struct only if needed. Do not free!
93 const struct GNUNET_HashCode *namespace;
96 * Identity of a peer hosting the content, otherwise NULl.
97 * Allocated after struct only if needed. Do not free!
99 const struct GNUNET_PeerIdentity *target;
102 * Fields for the plan module to track a DLL with the request.
104 struct GSF_PendingRequestPlanBijection *pr_head;
107 * Fields for the plan module to track a DLL with the request.
109 struct GSF_PendingRequestPlanBijection *pr_tail;
112 * Current TTL for the request.
114 struct GNUNET_TIME_Absolute ttl;
117 * When did we start with the request.
119 struct GNUNET_TIME_Absolute start_time;
122 * Desired anonymity level.
124 uint32_t anonymity_level;
127 * Priority that this request (still) has for us.
132 * Priority that this request (originally) had for us.
134 uint32_t original_priority;
137 * Counter for how often this request has been transmitted (estimate,
138 * because we might have the same request pending for multiple clients,
139 * and of course because a transmission may have failed at a lower
142 uint32_t num_transmissions;
145 * How much respect did we (in total) offer for this request so far (estimate,
146 * because we might have the same request pending for multiple clients,
147 * and of course because a transmission may have failed at a lower
150 uint32_t respect_offered;
153 * Options for the request.
155 enum GSF_PendingRequestOptions options;
158 * Type of the requested block.
160 enum GNUNET_BLOCK_Type type;
163 * Number of results we have found for this request so far.
165 unsigned int results_found;
168 * Has this request been started yet (local/p2p operations)? Or are
169 * we still constructing it?
177 * Handle a reply to a pending request. Also called if a request
178 * expires (then with data == NULL). The handler may be called
179 * many times (depending on the request type), but will not be
180 * called during or after a call to GSF_pending_request_cancel
181 * and will also not be called anymore after a call signalling
184 * @param cls user-specified closure
185 * @param eval evaluation of the result
186 * @param pr handle to the original pending request
187 * @param reply_anonymity_level anonymity level for the reply, UINT32_MAX for "unknown"
188 * @param expiration when does 'data' expire?
189 * @param last_transmission the last time we've tried to get this block (FOREVER if unknown)
190 * @param type type of the block
191 * @param data response data, NULL on request expiration
192 * @param data_len number of bytes in data
194 typedef void (*GSF_PendingRequestReplyHandler) (void *cls,
196 GNUNET_BLOCK_EvaluationResult
198 struct GSF_PendingRequest * pr,
199 uint32_t reply_anonymity_level,
200 struct GNUNET_TIME_Absolute
202 struct GNUNET_TIME_Absolute
204 enum GNUNET_BLOCK_Type type,
210 * Create a new pending request.
212 * @param options request options
213 * @param type type of the block that is being requested
214 * @param query key for the lookup
215 * @param namespace namespace to lookup, NULL for no namespace
216 * @param target preferred target for the request, NULL for none
217 * @param bf_data raw data for bloom filter for known replies, can be NULL
218 * @param bf_size number of bytes in bf_data
219 * @param mingle mingle value for bf
220 * @param anonymity_level desired anonymity level
221 * @param priority maximum outgoing cummulative request priority to use
222 * @param ttl current time-to-live for the request
223 * @param sender_pid peer ID to use for the sender when forwarding, 0 for none;
224 * reference counter is taken over by this function
225 * @param origin_pid peer ID of origin of query (do not loop back)
226 * @param replies_seen hash codes of known local replies
227 * @param replies_seen_count size of the 'replies_seen' array
228 * @param rh handle to call when we get a reply
229 * @param rh_cls closure for rh
230 * @return handle for the new pending request
232 struct GSF_PendingRequest *
233 GSF_pending_request_create_ (enum GSF_PendingRequestOptions options,
234 enum GNUNET_BLOCK_Type type,
235 const struct GNUNET_HashCode * query,
236 const struct GNUNET_HashCode * namespace,
237 const struct GNUNET_PeerIdentity *target,
238 const char *bf_data, size_t bf_size,
239 uint32_t mingle, uint32_t anonymity_level,
240 uint32_t priority, int32_t ttl,
241 GNUNET_PEER_Id sender_pid,
242 GNUNET_PEER_Id origin_pid,
243 const struct GNUNET_HashCode * replies_seen,
244 unsigned int replies_seen_count,
245 GSF_PendingRequestReplyHandler rh, void *rh_cls);
249 * Update a given pending request with additional replies
250 * that have been seen.
252 * @param pr request to update
253 * @param replies_seen hash codes of replies that we've seen
254 * @param replies_seen_count size of the replies_seen array
257 GSF_pending_request_update_ (struct GSF_PendingRequest *pr,
258 const struct GNUNET_HashCode * replies_seen,
259 unsigned int replies_seen_count);
263 * Obtain the public data associated with a pending request
265 * @param pr pending request
266 * @return associated public data
268 struct GSF_PendingRequestData *
269 GSF_pending_request_get_data_ (struct GSF_PendingRequest *pr);
273 * Test if two pending requests are compatible (would generate
274 * the same query modulo filters and should thus be processed
277 * @param pra a pending request
278 * @param prb another pending request
279 * @return GNUNET_OK if the requests are compatible
282 GSF_pending_request_is_compatible_ (struct GSF_PendingRequest *pra,
283 struct GSF_PendingRequest *prb);
287 * Generate the message corresponding to the given pending request for
288 * transmission to other peers (or at least determine its size).
290 * @param pr request to generate the message for
291 * @param buf_size number of bytes available in buf
292 * @param buf where to copy the message (can be NULL)
293 * @return number of bytes needed (if buf_size too small) or used
296 GSF_pending_request_get_message_ (struct GSF_PendingRequest *pr,
297 size_t buf_size, void *buf);
301 * Explicitly cancel a pending request.
303 * @param pr request to cancel
304 * @param full_cleanup fully purge the request
307 GSF_pending_request_cancel_ (struct GSF_PendingRequest *pr, int full_cleanup);
311 * Signature of function called on each request.
312 * (Note: 'subtype' of GNUNET_CONTAINER_HashMapIterator).
315 * @param key query for the request
316 * @param pr handle to the pending request
317 * @return GNUNET_YES to continue to iterate
319 typedef int (*GSF_PendingRequestIterator) (void *cls,
320 const struct GNUNET_HashCode * key,
321 struct GSF_PendingRequest * pr);
325 * Iterate over all pending requests.
327 * @param it function to call for each request
328 * @param cls closure for it
331 GSF_iterate_pending_requests_ (GSF_PendingRequestIterator it, void *cls);
335 * Handle P2P "CONTENT" message. Checks that the message is
336 * well-formed and then checks if there are any pending requests for
337 * this content and possibly passes it on (to local clients or other
338 * peers). Does NOT perform migration (content caching at this peer).
340 * @param cp the other peer involved (sender or receiver, NULL
341 * for loopback messages where we are both sender and receiver)
342 * @param message the actual message
343 * @return GNUNET_OK if the message was well-formed,
344 * GNUNET_SYSERR if the message was malformed (close connection,
345 * do not cache under any circumstances)
348 GSF_handle_p2p_content_ (struct GSF_ConnectedPeer *cp,
349 const struct GNUNET_MessageHeader *message);
353 * Consider looking up the data in the DHT (anonymity-level permitting).
355 * @param pr the pending request to process
358 GSF_dht_lookup_ (struct GSF_PendingRequest *pr);
362 * Consider downloading via stream (if possible)
364 * @param pr the pending request to process
367 GSF_stream_lookup_ (struct GSF_PendingRequest *pr);
371 * Function to be called after we're done processing
372 * replies from the local lookup.
375 * @param pr the pending request we were processing
376 * @param result final datastore lookup result
378 typedef void (*GSF_LocalLookupContinuation) (void *cls,
379 struct GSF_PendingRequest * pr,
380 enum GNUNET_BLOCK_EvaluationResult
385 * Look up the request in the local datastore.
387 * @param pr the pending request to process
388 * @param cont function to call at the end
389 * @param cont_cls closure for cont
392 GSF_local_lookup_ (struct GSF_PendingRequest *pr,
393 GSF_LocalLookupContinuation cont, void *cont_cls);
397 * Is the given target a legitimate peer for forwarding the given request?
401 * @return GNUNET_YES if this request could be forwarded to the given peer
404 GSF_pending_request_test_target_ (struct GSF_PendingRequest *pr,
405 const struct GNUNET_PeerIdentity *target);
410 * Setup the subsystem.
413 GSF_pending_request_init_ (void);
417 * Shutdown the subsystem.
420 GSF_pending_request_done_ (void);
424 /* end of gnunet-service-fs_pr.h */