2 This file is part of GNUnet
3 (C) 2004-2013 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.
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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 datastore/datastore_api.c
23 * @brief Management for the datastore for files stored on a GNUnet node. Implements
24 * a priority queue for requests (with timeouts).
25 * @author Christian Grothoff
28 #include "gnunet_arm_service.h"
29 #include "gnunet_constants.h"
30 #include "gnunet_datastore_service.h"
31 #include "gnunet_statistics_service.h"
32 #include "datastore.h"
34 #define LOG(kind,...) GNUNET_log_from (kind, "datastore-api",__VA_ARGS__)
37 * Collect an instane number of statistics? May cause excessive IPC.
39 #define INSANE_STATISTICS GNUNET_NO
42 * If a client stopped asking for more results, how many more do
43 * we receive from the DB before killing the connection? Trade-off
44 * between re-doing TCP handshakes and (needlessly) receiving
47 #define MAX_EXCESS_RESULTS 8
50 * Context for processing status messages.
55 * Continuation to call with the status.
57 GNUNET_DATASTORE_ContinuationWithStatus cont;
68 * Context for processing result messages.
73 * Function to call with the result.
75 GNUNET_DATASTORE_DatumProcessor proc;
86 * Context for a queue operation.
91 struct StatusContext sc;
93 struct ResultContext rc;
100 * Entry in our priority queue.
102 struct GNUNET_DATASTORE_QueueEntry
106 * This is a linked list.
108 struct GNUNET_DATASTORE_QueueEntry *next;
111 * This is a linked list.
113 struct GNUNET_DATASTORE_QueueEntry *prev;
116 * Handle to the master context.
118 struct GNUNET_DATASTORE_Handle *h;
121 * Response processor (NULL if we are not waiting for a response).
122 * This struct should be used for the closure, function-specific
123 * arguments can be passed via 'qc'.
125 GNUNET_CLIENT_MessageHandler response_proc;
128 * Function to call after transmission of the request.
130 GNUNET_DATASTORE_ContinuationWithStatus cont;
133 * Closure for 'cont'.
138 * Context for the operation.
140 union QueueContext qc;
143 * Task for timeout signalling.
145 struct GNUNET_SCHEDULER_Task * task;
148 * Timeout for the current operation.
150 struct GNUNET_TIME_Absolute timeout;
153 * Priority in the queue.
155 unsigned int priority;
158 * Maximum allowed length of queue (otherwise
159 * this request should be discarded).
161 unsigned int max_queue;
164 * Number of bytes in the request message following
165 * this struct. 32-bit value for nicer memory
166 * access (and overall struct alignment).
168 uint32_t message_size;
171 * Has this message been transmitted to the service?
172 * Only ever GNUNET_YES for the head of the queue.
173 * Note that the overall struct should end at a
174 * multiple of 64 bits.
181 * Handle to the datastore service.
183 struct GNUNET_DATASTORE_Handle
189 const struct GNUNET_CONFIGURATION_Handle *cfg;
192 * Current connection to the datastore service.
194 struct GNUNET_CLIENT_Connection *client;
197 * Handle for statistics.
199 struct GNUNET_STATISTICS_Handle *stats;
202 * Current transmit handle.
204 struct GNUNET_CLIENT_TransmitHandle *th;
207 * Current head of priority queue.
209 struct GNUNET_DATASTORE_QueueEntry *queue_head;
212 * Current tail of priority queue.
214 struct GNUNET_DATASTORE_QueueEntry *queue_tail;
217 * Task for trying to reconnect.
219 struct GNUNET_SCHEDULER_Task * reconnect_task;
222 * How quickly should we retry? Used for exponential back-off on
225 struct GNUNET_TIME_Relative retry_time;
228 * Number of entries in the queue.
230 unsigned int queue_size;
233 * Number of results we're receiving for the current query
234 * after application stopped to care. Used to determine when
235 * to reset the connection.
237 unsigned int result_count;
240 * Are we currently trying to receive from the service?
245 * We should ignore the next message(s) from the service.
247 unsigned int skip_next_messages;
254 * Connect to the datastore service.
256 * @param cfg configuration to use
257 * @return handle to use to access the service
259 struct GNUNET_DATASTORE_Handle *
260 GNUNET_DATASTORE_connect (const struct GNUNET_CONFIGURATION_Handle *cfg)
262 struct GNUNET_CLIENT_Connection *c;
263 struct GNUNET_DATASTORE_Handle *h;
265 c = GNUNET_CLIENT_connect ("datastore", cfg);
267 return NULL; /* oops */
268 h = GNUNET_malloc (sizeof (struct GNUNET_DATASTORE_Handle) +
269 GNUNET_SERVER_MAX_MESSAGE_SIZE - 1);
272 h->stats = GNUNET_STATISTICS_create ("datastore-api", cfg);
278 * Task used by 'transmit_drop' to disconnect the datastore.
280 * @param cls the datastore handle
281 * @param tc scheduler context
284 disconnect_after_drop (void *cls,
285 const struct GNUNET_SCHEDULER_TaskContext *tc)
287 struct GNUNET_DATASTORE_Handle *h = cls;
289 GNUNET_DATASTORE_disconnect (h, GNUNET_NO);
294 * Transmit DROP message to datastore service.
296 * @param cls the `struct GNUNET_DATASTORE_Handle`
297 * @param size number of bytes that can be copied to @a buf
298 * @param buf where to copy the drop message
299 * @return number of bytes written to @a buf
302 transmit_drop (void *cls, size_t size, void *buf)
304 struct GNUNET_DATASTORE_Handle *h = cls;
305 struct GNUNET_MessageHeader *hdr;
309 LOG (GNUNET_ERROR_TYPE_WARNING,
310 _("Failed to transmit request to drop database.\n"));
311 GNUNET_SCHEDULER_add_continuation (&disconnect_after_drop, h,
312 GNUNET_SCHEDULER_REASON_PREREQ_DONE);
315 GNUNET_assert (size >= sizeof (struct GNUNET_MessageHeader));
317 hdr->size = htons (sizeof (struct GNUNET_MessageHeader));
318 hdr->type = htons (GNUNET_MESSAGE_TYPE_DATASTORE_DROP);
319 GNUNET_SCHEDULER_add_continuation (&disconnect_after_drop, h,
320 GNUNET_SCHEDULER_REASON_PREREQ_DONE);
321 return sizeof (struct GNUNET_MessageHeader);
326 * Disconnect from the datastore service (and free
327 * associated resources).
329 * @param h handle to the datastore
330 * @param drop set to #GNUNET_YES to delete all data in datastore (!)
333 GNUNET_DATASTORE_disconnect (struct GNUNET_DATASTORE_Handle *h, int drop)
335 struct GNUNET_DATASTORE_QueueEntry *qe;
337 LOG (GNUNET_ERROR_TYPE_DEBUG, "Datastore disconnect\n");
340 GNUNET_CLIENT_notify_transmit_ready_cancel (h->th);
343 if (h->client != NULL)
345 GNUNET_CLIENT_disconnect (h->client);
348 if (h->reconnect_task != NULL)
350 GNUNET_SCHEDULER_cancel (h->reconnect_task);
351 h->reconnect_task = NULL;
353 while (NULL != (qe = h->queue_head))
355 GNUNET_assert (NULL != qe->response_proc);
356 qe->response_proc (h, NULL);
358 if (GNUNET_YES == drop)
360 h->client = GNUNET_CLIENT_connect ("datastore", h->cfg);
361 if (h->client != NULL)
364 GNUNET_CLIENT_notify_transmit_ready (h->client,
366 GNUNET_MessageHeader),
367 GNUNET_TIME_UNIT_MINUTES,
368 GNUNET_YES, &transmit_drop, h))
370 GNUNET_CLIENT_disconnect (h->client);
375 GNUNET_STATISTICS_destroy (h->stats, GNUNET_NO);
382 * A request has timed out (before being transmitted to the service).
384 * @param cls the `struct GNUNET_DATASTORE_QueueEntry`
385 * @param tc scheduler context
388 timeout_queue_entry (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
390 struct GNUNET_DATASTORE_QueueEntry *qe = cls;
391 struct GNUNET_DATASTORE_Handle *h = qe->h;
393 GNUNET_STATISTICS_update (h->stats,
394 gettext_noop ("# queue entry timeouts"), 1,
397 GNUNET_assert (GNUNET_NO == qe->was_transmitted);
398 LOG (GNUNET_ERROR_TYPE_DEBUG,
399 "Timeout of request in datastore queue\n");
400 /* response_proc's expect request at the head of the queue! */
401 GNUNET_CONTAINER_DLL_remove (h->queue_head, h->queue_tail, qe);
402 GNUNET_CONTAINER_DLL_insert (h->queue_head, h->queue_tail, qe);
403 GNUNET_assert (h->queue_head == qe);
404 qe->response_proc (qe->h, NULL);
409 * Create a new entry for our priority queue (and possibly discard other entires if
410 * the queue is getting too long).
412 * @param h handle to the datastore
413 * @param msize size of the message to queue
414 * @param queue_priority priority of the entry
415 * @param max_queue_size at what queue size should this request be dropped
416 * (if other requests of higher priority are in the queue)
417 * @param timeout timeout for the operation
418 * @param response_proc function to call with replies (can be NULL)
419 * @param qc client context (NOT a closure for @a response_proc)
420 * @return NULL if the queue is full
422 static struct GNUNET_DATASTORE_QueueEntry *
423 make_queue_entry (struct GNUNET_DATASTORE_Handle *h, size_t msize,
424 unsigned int queue_priority, unsigned int max_queue_size,
425 struct GNUNET_TIME_Relative timeout,
426 GNUNET_CLIENT_MessageHandler response_proc,
427 const union QueueContext *qc)
429 struct GNUNET_DATASTORE_QueueEntry *ret;
430 struct GNUNET_DATASTORE_QueueEntry *pos;
435 while ((pos != NULL) && (c < max_queue_size) &&
436 (pos->priority >= queue_priority))
441 if (c >= max_queue_size)
443 GNUNET_STATISTICS_update (h->stats, gettext_noop ("# queue overflows"), 1,
447 ret = GNUNET_malloc (sizeof (struct GNUNET_DATASTORE_QueueEntry) + msize);
449 ret->response_proc = response_proc;
451 ret->timeout = GNUNET_TIME_relative_to_absolute (timeout);
452 ret->priority = queue_priority;
453 ret->max_queue = max_queue_size;
454 ret->message_size = msize;
455 ret->was_transmitted = GNUNET_NO;
458 /* append at the tail */
464 /* do not insert at HEAD if HEAD query was already
465 * transmitted and we are still receiving replies! */
466 if ((pos == NULL) && (h->queue_head->was_transmitted))
470 #if INSANE_STATISTICS
471 GNUNET_STATISTICS_update (h->stats, gettext_noop ("# queue entries created"),
474 GNUNET_CONTAINER_DLL_insert_after (h->queue_head, h->queue_tail, pos, ret);
476 ret->task = GNUNET_SCHEDULER_add_delayed (timeout, &timeout_queue_entry, ret);
477 for (pos = ret->next; NULL != pos; pos = pos->next)
479 if ((pos->max_queue < h->queue_size) && (pos->was_transmitted == GNUNET_NO))
481 GNUNET_assert (NULL != pos->response_proc);
482 /* move 'pos' element to head so that it will be
483 * killed on 'NULL' call below */
484 LOG (GNUNET_ERROR_TYPE_DEBUG,
485 "Dropping request from datastore queue\n");
486 /* response_proc's expect request at the head of the queue! */
487 GNUNET_CONTAINER_DLL_remove (h->queue_head, h->queue_tail, pos);
488 GNUNET_CONTAINER_DLL_insert (h->queue_head, h->queue_tail, pos);
489 GNUNET_STATISTICS_update (h->stats,
491 ("# Requests dropped from datastore queue"), 1,
493 GNUNET_assert (h->queue_head == pos);
494 pos->response_proc (h, NULL);
503 * Process entries in the queue (or do nothing if we are already
506 * @param h handle to the datastore
509 process_queue (struct GNUNET_DATASTORE_Handle *h);
513 * Try reconnecting to the datastore service.
515 * @param cls the `struct GNUNET_DATASTORE_Handle`
516 * @param tc scheduler context
519 try_reconnect (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
521 struct GNUNET_DATASTORE_Handle *h = cls;
523 h->retry_time = GNUNET_TIME_STD_BACKOFF (h->retry_time);
524 h->reconnect_task = NULL;
525 h->client = GNUNET_CLIENT_connect ("datastore", h->cfg);
526 if (h->client == NULL)
528 LOG (GNUNET_ERROR_TYPE_ERROR, "DATASTORE reconnect failed (fatally)\n");
531 GNUNET_STATISTICS_update (h->stats,
533 ("# datastore connections (re)created"), 1,
535 LOG (GNUNET_ERROR_TYPE_DEBUG, "Reconnected to DATASTORE\n");
541 * Disconnect from the service and then try reconnecting to the datastore service
544 * @param h handle to datastore to disconnect and reconnect
547 do_disconnect (struct GNUNET_DATASTORE_Handle *h)
549 if (NULL == h->client)
551 LOG (GNUNET_ERROR_TYPE_DEBUG,
552 "Client NULL in disconnect, will not try to reconnect\n");
555 GNUNET_CLIENT_disconnect (h->client);
556 h->skip_next_messages = 0;
559 GNUNET_SCHEDULER_add_delayed (h->retry_time, &try_reconnect, h);
564 * Function called whenever we receive a message from
565 * the service. Calls the appropriate handler.
567 * @param cls the `struct GNUNET_DATASTORE_Handle`
568 * @param msg the received message
571 receive_cb (void *cls,
572 const struct GNUNET_MessageHeader *msg)
574 struct GNUNET_DATASTORE_Handle *h = cls;
575 struct GNUNET_DATASTORE_QueueEntry *qe;
577 h->in_receive = GNUNET_NO;
578 LOG (GNUNET_ERROR_TYPE_DEBUG,
579 "Receiving reply from datastore\n");
580 if (h->skip_next_messages > 0)
582 h->skip_next_messages--;
586 if (NULL == (qe = h->queue_head))
592 qe->response_proc (h, msg);
597 * Transmit request from queue to datastore service.
599 * @param cls the `struct GNUNET_DATASTORE_Handle`
600 * @param size number of bytes that can be copied to @a buf
601 * @param buf where to copy the drop message
602 * @return number of bytes written to @a buf
605 transmit_request (void *cls,
609 struct GNUNET_DATASTORE_Handle *h = cls;
610 struct GNUNET_DATASTORE_QueueEntry *qe;
614 if (NULL == (qe = h->queue_head))
615 return 0; /* no entry in queue */
618 LOG (GNUNET_ERROR_TYPE_DEBUG,
619 "Failed to transmit request to DATASTORE.\n");
620 GNUNET_STATISTICS_update (h->stats,
621 gettext_noop ("# transmission request failures"),
626 if (size < (msize = qe->message_size))
631 LOG (GNUNET_ERROR_TYPE_DEBUG,
632 "Transmitting %u byte request to DATASTORE\n",
634 memcpy (buf, &qe[1], msize);
635 qe->was_transmitted = GNUNET_YES;
636 GNUNET_SCHEDULER_cancel (qe->task);
638 GNUNET_assert (GNUNET_NO == h->in_receive);
639 h->in_receive = GNUNET_YES;
640 GNUNET_CLIENT_receive (h->client,
642 GNUNET_TIME_absolute_get_remaining (qe->timeout));
643 #if INSANE_STATISTICS
644 GNUNET_STATISTICS_update (h->stats,
645 gettext_noop ("# bytes sent to datastore"), 1,
653 * Process entries in the queue (or do nothing if we are already
656 * @param h handle to the datastore
659 process_queue (struct GNUNET_DATASTORE_Handle *h)
661 struct GNUNET_DATASTORE_QueueEntry *qe;
663 if (NULL == (qe = h->queue_head))
665 /* no entry in queue */
666 LOG (GNUNET_ERROR_TYPE_DEBUG,
670 if (GNUNET_YES == qe->was_transmitted)
672 /* waiting for replies */
673 LOG (GNUNET_ERROR_TYPE_DEBUG,
674 "Head request already transmitted\n");
679 /* request pending */
680 LOG (GNUNET_ERROR_TYPE_DEBUG,
681 "Pending transmission request\n");
684 if (NULL == h->client)
686 /* waiting for reconnect */
687 LOG (GNUNET_ERROR_TYPE_DEBUG,
691 if (GNUNET_YES == h->in_receive)
693 /* wait for response to previous query */
696 LOG (GNUNET_ERROR_TYPE_DEBUG,
697 "Queueing %u byte request to DATASTORE\n",
700 = GNUNET_CLIENT_notify_transmit_ready (h->client, qe->message_size,
701 GNUNET_TIME_absolute_get_remaining (qe->timeout),
703 &transmit_request, h);
704 GNUNET_assert (GNUNET_NO == h->in_receive);
705 GNUNET_break (NULL != h->th);
710 * Dummy continuation used to do nothing (but be non-zero).
713 * @param result result
714 * @param min_expiration expiration time
715 * @param emsg error message
718 drop_status_cont (void *cls, int32_t result,
719 struct GNUNET_TIME_Absolute min_expiration,
727 * Free a queue entry. Removes the given entry from the
728 * queue and releases associated resources. Does NOT
731 * @param qe entry to free.
734 free_queue_entry (struct GNUNET_DATASTORE_QueueEntry *qe)
736 struct GNUNET_DATASTORE_Handle *h = qe->h;
738 GNUNET_CONTAINER_DLL_remove (h->queue_head, h->queue_tail, qe);
739 if (qe->task != NULL)
741 GNUNET_SCHEDULER_cancel (qe->task);
745 qe->was_transmitted = GNUNET_SYSERR; /* use-after-free warning */
751 * Type of a function to call when we receive a message
755 * @param msg message received, NULL on timeout or fatal error
758 process_status_message (void *cls,
759 const struct GNUNET_MessageHeader *msg)
761 struct GNUNET_DATASTORE_Handle *h = cls;
762 struct GNUNET_DATASTORE_QueueEntry *qe;
763 struct StatusContext rc;
764 const struct StatusMessage *sm;
769 if (NULL == (qe = h->queue_head))
778 was_transmitted = qe->was_transmitted;
779 free_queue_entry (qe);
780 if (was_transmitted == GNUNET_YES)
785 rc.cont (rc.cont_cls, GNUNET_SYSERR,
786 GNUNET_TIME_UNIT_ZERO_ABS,
787 _("Failed to receive status response from database."));
790 GNUNET_assert (GNUNET_YES == qe->was_transmitted);
791 free_queue_entry (qe);
792 if ((ntohs (msg->size) < sizeof (struct StatusMessage)) ||
793 (ntohs (msg->type) != GNUNET_MESSAGE_TYPE_DATASTORE_STATUS))
796 h->retry_time = GNUNET_TIME_UNIT_ZERO;
799 rc.cont (rc.cont_cls, GNUNET_SYSERR,
800 GNUNET_TIME_UNIT_ZERO_ABS,
801 _("Error reading response from datastore service"));
804 sm = (const struct StatusMessage *) msg;
805 status = ntohl (sm->status);
807 if (ntohs (msg->size) > sizeof (struct StatusMessage))
809 emsg = (const char *) &sm[1];
810 if (emsg[ntohs (msg->size) - sizeof (struct StatusMessage) - 1] != '\0')
813 emsg = _("Invalid error message received from datastore service");
816 if ((status == GNUNET_SYSERR) && (emsg == NULL))
819 emsg = _("Invalid error message received from datastore service");
821 LOG (GNUNET_ERROR_TYPE_DEBUG, "Received status %d/%s\n", (int) status, emsg);
822 GNUNET_STATISTICS_update (h->stats,
823 gettext_noop ("# status messages received"), 1,
825 h->retry_time = GNUNET_TIME_UNIT_ZERO;
828 rc.cont (rc.cont_cls, status,
829 GNUNET_TIME_absolute_ntoh (sm->min_expiration),
835 * Store an item in the datastore. If the item is already present,
836 * the priorities are summed up and the higher expiration time and
837 * lower anonymity level is used.
839 * @param h handle to the datastore
840 * @param rid reservation ID to use (from "reserve"); use 0 if no
841 * prior reservation was made
842 * @param key key for the value
843 * @param size number of bytes in data
844 * @param data content stored
845 * @param type type of the content
846 * @param priority priority of the content
847 * @param anonymity anonymity-level for the content
848 * @param replication how often should the content be replicated to other peers?
849 * @param expiration expiration time for the content
850 * @param queue_priority ranking of this request in the priority queue
851 * @param max_queue_size at what queue size should this request be dropped
852 * (if other requests of higher priority are in the queue)
853 * @param timeout timeout for the operation
854 * @param cont continuation to call when done
855 * @param cont_cls closure for @a cont
856 * @return NULL if the entry was not queued, otherwise a handle that can be used to
857 * cancel; note that even if NULL is returned, the callback will be invoked
858 * (or rather, will already have been invoked)
860 struct GNUNET_DATASTORE_QueueEntry *
861 GNUNET_DATASTORE_put (struct GNUNET_DATASTORE_Handle *h, uint32_t rid,
862 const struct GNUNET_HashCode * key, size_t size,
863 const void *data, enum GNUNET_BLOCK_Type type,
864 uint32_t priority, uint32_t anonymity,
865 uint32_t replication,
866 struct GNUNET_TIME_Absolute expiration,
867 unsigned int queue_priority, unsigned int max_queue_size,
868 struct GNUNET_TIME_Relative timeout,
869 GNUNET_DATASTORE_ContinuationWithStatus cont,
872 struct GNUNET_DATASTORE_QueueEntry *qe;
873 struct DataMessage *dm;
875 union QueueContext qc;
877 LOG (GNUNET_ERROR_TYPE_DEBUG,
878 "Asked to put %u bytes of data under key `%s' for %s\n", size,
880 GNUNET_STRINGS_relative_time_to_string (GNUNET_TIME_absolute_get_remaining (expiration),
882 msize = sizeof (struct DataMessage) + size;
883 GNUNET_assert (msize < GNUNET_SERVER_MAX_MESSAGE_SIZE);
885 qc.sc.cont_cls = cont_cls;
886 qe = make_queue_entry (h, msize, queue_priority, max_queue_size, timeout,
887 &process_status_message, &qc);
890 LOG (GNUNET_ERROR_TYPE_DEBUG, "Could not create queue entry for PUT\n");
893 GNUNET_STATISTICS_update (h->stats, gettext_noop ("# PUT requests executed"),
895 dm = (struct DataMessage *) &qe[1];
896 dm->header.type = htons (GNUNET_MESSAGE_TYPE_DATASTORE_PUT);
897 dm->header.size = htons (msize);
898 dm->rid = htonl (rid);
899 dm->size = htonl ((uint32_t) size);
900 dm->type = htonl (type);
901 dm->priority = htonl (priority);
902 dm->anonymity = htonl (anonymity);
903 dm->replication = htonl (replication);
904 dm->reserved = htonl (0);
905 dm->uid = GNUNET_htonll (0);
906 dm->expiration = GNUNET_TIME_absolute_hton (expiration);
908 memcpy (&dm[1], data, size);
915 * Reserve space in the datastore. This function should be used
916 * to avoid "out of space" failures during a longer sequence of "put"
917 * operations (for example, when a file is being inserted).
919 * @param h handle to the datastore
920 * @param amount how much space (in bytes) should be reserved (for content only)
921 * @param entries how many entries will be created (to calculate per-entry overhead)
922 * @param cont continuation to call when done; "success" will be set to
923 * a positive reservation value if space could be reserved.
924 * @param cont_cls closure for @a cont
925 * @return NULL if the entry was not queued, otherwise a handle that can be used to
926 * cancel; note that even if NULL is returned, the callback will be invoked
927 * (or rather, will already have been invoked)
929 struct GNUNET_DATASTORE_QueueEntry *
930 GNUNET_DATASTORE_reserve (struct GNUNET_DATASTORE_Handle *h, uint64_t amount,
932 GNUNET_DATASTORE_ContinuationWithStatus cont,
935 struct GNUNET_DATASTORE_QueueEntry *qe;
936 struct ReserveMessage *rm;
937 union QueueContext qc;
940 cont = &drop_status_cont;
941 LOG (GNUNET_ERROR_TYPE_DEBUG,
942 "Asked to reserve %llu bytes of data and %u entries\n",
943 (unsigned long long) amount, (unsigned int) entries);
945 qc.sc.cont_cls = cont_cls;
946 qe = make_queue_entry (h,
947 sizeof (struct ReserveMessage),
950 GNUNET_TIME_UNIT_FOREVER_REL,
951 &process_status_message, &qc);
954 LOG (GNUNET_ERROR_TYPE_DEBUG,
955 "Could not create queue entry to reserve\n");
958 GNUNET_STATISTICS_update (h->stats,
959 gettext_noop ("# RESERVE requests executed"), 1,
961 rm = (struct ReserveMessage *) &qe[1];
962 rm->header.type = htons (GNUNET_MESSAGE_TYPE_DATASTORE_RESERVE);
963 rm->header.size = htons (sizeof (struct ReserveMessage));
964 rm->entries = htonl (entries);
965 rm->amount = GNUNET_htonll (amount);
972 * Signal that all of the data for which a reservation was made has
973 * been stored and that whatever excess space might have been reserved
974 * can now be released.
976 * @param h handle to the datastore
977 * @param rid reservation ID (value of "success" in original continuation
978 * from the "reserve" function).
979 * @param queue_priority ranking of this request in the priority queue
980 * @param max_queue_size at what queue size should this request be dropped
981 * (if other requests of higher priority are in the queue)
982 * @param queue_priority ranking of this request in the priority queue
983 * @param max_queue_size at what queue size should this request be dropped
984 * (if other requests of higher priority are in the queue)
985 * @param timeout how long to wait at most for a response
986 * @param cont continuation to call when done
987 * @param cont_cls closure for @a cont
988 * @return NULL if the entry was not queued, otherwise a handle that can be used to
989 * cancel; note that even if NULL is returned, the callback will be invoked
990 * (or rather, will already have been invoked)
992 struct GNUNET_DATASTORE_QueueEntry *
993 GNUNET_DATASTORE_release_reserve (struct GNUNET_DATASTORE_Handle *h,
994 uint32_t rid, unsigned int queue_priority,
995 unsigned int max_queue_size,
996 struct GNUNET_TIME_Relative timeout,
997 GNUNET_DATASTORE_ContinuationWithStatus cont,
1000 struct GNUNET_DATASTORE_QueueEntry *qe;
1001 struct ReleaseReserveMessage *rrm;
1002 union QueueContext qc;
1005 cont = &drop_status_cont;
1006 LOG (GNUNET_ERROR_TYPE_DEBUG, "Asked to release reserve %d\n", rid);
1008 qc.sc.cont_cls = cont_cls;
1009 qe = make_queue_entry (h, sizeof (struct ReleaseReserveMessage),
1010 queue_priority, max_queue_size, timeout,
1011 &process_status_message, &qc);
1014 LOG (GNUNET_ERROR_TYPE_DEBUG,
1015 "Could not create queue entry to release reserve\n");
1018 GNUNET_STATISTICS_update (h->stats,
1020 ("# RELEASE RESERVE requests executed"), 1,
1022 rrm = (struct ReleaseReserveMessage *) &qe[1];
1023 rrm->header.type = htons (GNUNET_MESSAGE_TYPE_DATASTORE_RELEASE_RESERVE);
1024 rrm->header.size = htons (sizeof (struct ReleaseReserveMessage));
1025 rrm->rid = htonl (rid);
1032 * Update a value in the datastore.
1034 * @param h handle to the datastore
1035 * @param uid identifier for the value
1036 * @param priority how much to increase the priority of the value
1037 * @param expiration new expiration value should be MAX of existing and this argument
1038 * @param queue_priority ranking of this request in the priority queue
1039 * @param max_queue_size at what queue size should this request be dropped
1040 * (if other requests of higher priority are in the queue)
1041 * @param timeout how long to wait at most for a response
1042 * @param cont continuation to call when done
1043 * @param cont_cls closure for @a cont
1044 * @return NULL if the entry was not queued, otherwise a handle that can be used to
1045 * cancel; note that even if NULL is returned, the callback will be invoked
1046 * (or rather, will already have been invoked)
1048 struct GNUNET_DATASTORE_QueueEntry *
1049 GNUNET_DATASTORE_update (struct GNUNET_DATASTORE_Handle *h, uint64_t uid,
1051 struct GNUNET_TIME_Absolute expiration,
1052 unsigned int queue_priority,
1053 unsigned int max_queue_size,
1054 struct GNUNET_TIME_Relative timeout,
1055 GNUNET_DATASTORE_ContinuationWithStatus cont,
1058 struct GNUNET_DATASTORE_QueueEntry *qe;
1059 struct UpdateMessage *um;
1060 union QueueContext qc;
1063 cont = &drop_status_cont;
1064 LOG (GNUNET_ERROR_TYPE_DEBUG,
1065 "Asked to update entry %llu raising priority by %u and expiration to %s\n",
1067 (unsigned int) priority,
1068 GNUNET_STRINGS_absolute_time_to_string (expiration));
1070 qc.sc.cont_cls = cont_cls;
1071 qe = make_queue_entry (h, sizeof (struct UpdateMessage), queue_priority,
1072 max_queue_size, timeout, &process_status_message, &qc);
1075 LOG (GNUNET_ERROR_TYPE_DEBUG,
1076 "Could not create queue entry for UPDATE\n");
1079 GNUNET_STATISTICS_update (h->stats,
1080 gettext_noop ("# UPDATE requests executed"), 1,
1082 um = (struct UpdateMessage *) &qe[1];
1083 um->header.type = htons (GNUNET_MESSAGE_TYPE_DATASTORE_UPDATE);
1084 um->header.size = htons (sizeof (struct UpdateMessage));
1085 um->priority = htonl (priority);
1086 um->expiration = GNUNET_TIME_absolute_hton (expiration);
1087 um->uid = GNUNET_htonll (uid);
1094 * Explicitly remove some content from the database.
1095 * The @a cont continuation will be called with `status`
1096 * #GNUNET_OK" if content was removed, #GNUNET_NO
1097 * if no matching entry was found and #GNUNET_SYSERR
1098 * on all other types of errors.
1100 * @param h handle to the datastore
1101 * @param key key for the value
1102 * @param size number of bytes in data
1103 * @param data content stored
1104 * @param queue_priority ranking of this request in the priority queue
1105 * @param max_queue_size at what queue size should this request be dropped
1106 * (if other requests of higher priority are in the queue)
1107 * @param timeout how long to wait at most for a response
1108 * @param cont continuation to call when done
1109 * @param cont_cls closure for @a cont
1110 * @return NULL if the entry was not queued, otherwise a handle that can be used to
1111 * cancel; note that even if NULL is returned, the callback will be invoked
1112 * (or rather, will already have been invoked)
1114 struct GNUNET_DATASTORE_QueueEntry *
1115 GNUNET_DATASTORE_remove (struct GNUNET_DATASTORE_Handle *h,
1116 const struct GNUNET_HashCode * key, size_t size,
1117 const void *data, unsigned int queue_priority,
1118 unsigned int max_queue_size,
1119 struct GNUNET_TIME_Relative timeout,
1120 GNUNET_DATASTORE_ContinuationWithStatus cont,
1123 struct GNUNET_DATASTORE_QueueEntry *qe;
1124 struct DataMessage *dm;
1126 union QueueContext qc;
1129 cont = &drop_status_cont;
1130 LOG (GNUNET_ERROR_TYPE_DEBUG, "Asked to remove %u bytes under key `%s'\n",
1131 size, GNUNET_h2s (key));
1133 qc.sc.cont_cls = cont_cls;
1134 msize = sizeof (struct DataMessage) + size;
1135 GNUNET_assert (msize < GNUNET_SERVER_MAX_MESSAGE_SIZE);
1136 qe = make_queue_entry (h, msize, queue_priority, max_queue_size, timeout,
1137 &process_status_message, &qc);
1140 LOG (GNUNET_ERROR_TYPE_DEBUG, "Could not create queue entry for REMOVE\n");
1143 GNUNET_STATISTICS_update (h->stats,
1144 gettext_noop ("# REMOVE requests executed"), 1,
1146 dm = (struct DataMessage *) &qe[1];
1147 dm->header.type = htons (GNUNET_MESSAGE_TYPE_DATASTORE_REMOVE);
1148 dm->header.size = htons (msize);
1149 dm->rid = htonl (0);
1150 dm->size = htonl (size);
1151 dm->type = htonl (0);
1152 dm->priority = htonl (0);
1153 dm->anonymity = htonl (0);
1154 dm->uid = GNUNET_htonll (0);
1155 dm->expiration = GNUNET_TIME_absolute_hton (GNUNET_TIME_UNIT_ZERO_ABS);
1157 memcpy (&dm[1], data, size);
1164 * Type of a function to call when we receive a message
1167 * @param cls closure with the `struct GNUNET_DATASTORE_Handle *`
1168 * @param msg message received, NULL on timeout or fatal error
1171 process_result_message (void *cls, const struct GNUNET_MessageHeader *msg)
1173 struct GNUNET_DATASTORE_Handle *h = cls;
1174 struct GNUNET_DATASTORE_QueueEntry *qe;
1175 struct ResultContext rc;
1176 const struct DataMessage *dm;
1177 int was_transmitted;
1182 GNUNET_assert (NULL != qe);
1184 was_transmitted = qe->was_transmitted;
1185 free_queue_entry (qe);
1186 if (GNUNET_YES == was_transmitted)
1188 LOG (GNUNET_ERROR_TYPE_WARNING,
1189 _("Failed to receive response from database.\n"));
1196 if (NULL != rc.proc)
1197 rc.proc (rc.proc_cls, NULL, 0, NULL, 0, 0, 0, GNUNET_TIME_UNIT_ZERO_ABS,
1201 if (ntohs (msg->type) == GNUNET_MESSAGE_TYPE_DATASTORE_DATA_END)
1203 GNUNET_break (ntohs (msg->size) == sizeof (struct GNUNET_MessageHeader));
1206 GNUNET_assert (GNUNET_YES == qe->was_transmitted);
1207 free_queue_entry (qe);
1208 LOG (GNUNET_ERROR_TYPE_DEBUG,
1209 "Received end of result set, new queue size is %u\n", h->queue_size);
1210 h->retry_time = GNUNET_TIME_UNIT_ZERO;
1211 h->result_count = 0;
1213 if (NULL != rc.proc)
1214 rc.proc (rc.proc_cls, NULL, 0, NULL, 0, 0, 0, GNUNET_TIME_UNIT_ZERO_ABS,
1219 GNUNET_assert (NULL != qe);
1221 if (GNUNET_YES != qe->was_transmitted)
1224 free_queue_entry (qe);
1225 h->retry_time = GNUNET_TIME_UNIT_ZERO;
1227 if (rc.proc != NULL)
1228 rc.proc (rc.proc_cls, NULL, 0, NULL, 0, 0, 0, GNUNET_TIME_UNIT_ZERO_ABS,
1232 if ((ntohs (msg->size) < sizeof (struct DataMessage)) ||
1233 (ntohs (msg->type) != GNUNET_MESSAGE_TYPE_DATASTORE_DATA) ||
1234 (ntohs (msg->size) !=
1235 sizeof (struct DataMessage) +
1236 ntohl (((const struct DataMessage *) msg)->size)))
1239 free_queue_entry (qe);
1240 h->retry_time = GNUNET_TIME_UNIT_ZERO;
1242 if (rc.proc != NULL)
1243 rc.proc (rc.proc_cls, NULL, 0, NULL, 0, 0, 0, GNUNET_TIME_UNIT_ZERO_ABS,
1247 #if INSANE_STATISTICS
1248 GNUNET_STATISTICS_update (h->stats, gettext_noop ("# Results received"), 1,
1251 dm = (const struct DataMessage *) msg;
1252 LOG (GNUNET_ERROR_TYPE_DEBUG,
1253 "Received result %llu with type %u and size %u with key %s\n",
1254 (unsigned long long) GNUNET_ntohll (dm->uid), ntohl (dm->type),
1255 ntohl (dm->size), GNUNET_h2s (&dm->key));
1256 free_queue_entry (qe);
1257 h->retry_time = GNUNET_TIME_UNIT_ZERO;
1259 if (rc.proc != NULL)
1260 rc.proc (rc.proc_cls, &dm->key, ntohl (dm->size), &dm[1], ntohl (dm->type),
1261 ntohl (dm->priority), ntohl (dm->anonymity),
1262 GNUNET_TIME_absolute_ntoh (dm->expiration),
1263 GNUNET_ntohll (dm->uid));
1268 * Get a random value from the datastore for content replication.
1269 * Returns a single, random value among those with the highest
1270 * replication score, lowering positive replication scores by one for
1271 * the chosen value (if only content with a replication score exists,
1272 * a random value is returned and replication scores are not changed).
1274 * @param h handle to the datastore
1275 * @param queue_priority ranking of this request in the priority queue
1276 * @param max_queue_size at what queue size should this request be dropped
1277 * (if other requests of higher priority are in the queue)
1278 * @param timeout how long to wait at most for a response
1279 * @param proc function to call on a random value; it
1280 * will be called once with a value (if available)
1281 * and always once with a value of NULL.
1282 * @param proc_cls closure for @a proc
1283 * @return NULL if the entry was not queued, otherwise a handle that can be used to
1286 struct GNUNET_DATASTORE_QueueEntry *
1287 GNUNET_DATASTORE_get_for_replication (struct GNUNET_DATASTORE_Handle *h,
1288 unsigned int queue_priority,
1289 unsigned int max_queue_size,
1290 struct GNUNET_TIME_Relative timeout,
1291 GNUNET_DATASTORE_DatumProcessor proc,
1294 struct GNUNET_DATASTORE_QueueEntry *qe;
1295 struct GNUNET_MessageHeader *m;
1296 union QueueContext qc;
1298 GNUNET_assert (NULL != proc);
1299 LOG (GNUNET_ERROR_TYPE_DEBUG,
1300 "Asked to get replication entry in %s\n",
1301 GNUNET_STRINGS_relative_time_to_string (timeout, GNUNET_YES));
1303 qc.rc.proc_cls = proc_cls;
1304 qe = make_queue_entry (h, sizeof (struct GNUNET_MessageHeader),
1305 queue_priority, max_queue_size, timeout,
1306 &process_result_message, &qc);
1309 LOG (GNUNET_ERROR_TYPE_DEBUG,
1310 "Could not create queue entry for GET REPLICATION\n");
1313 GNUNET_STATISTICS_update (h->stats,
1315 ("# GET REPLICATION requests executed"), 1,
1317 m = (struct GNUNET_MessageHeader *) &qe[1];
1318 m->type = htons (GNUNET_MESSAGE_TYPE_DATASTORE_GET_REPLICATION);
1319 m->size = htons (sizeof (struct GNUNET_MessageHeader));
1326 * Get a single zero-anonymity value from the datastore.
1328 * @param h handle to the datastore
1329 * @param offset offset of the result (modulo num-results); set to
1330 * a random 64-bit value initially; then increment by
1331 * one each time; detect that all results have been found by uid
1332 * being again the first uid ever returned.
1333 * @param queue_priority ranking of this request in the priority queue
1334 * @param max_queue_size at what queue size should this request be dropped
1335 * (if other requests of higher priority are in the queue)
1336 * @param timeout how long to wait at most for a response
1337 * @param type allowed type for the operation (never zero)
1338 * @param proc function to call on a random value; it
1339 * will be called once with a value (if available)
1340 * or with NULL if none value exists.
1341 * @param proc_cls closure for @a proc
1342 * @return NULL if the entry was not queued, otherwise a handle that can be used to
1345 struct GNUNET_DATASTORE_QueueEntry *
1346 GNUNET_DATASTORE_get_zero_anonymity (struct GNUNET_DATASTORE_Handle *h,
1348 unsigned int queue_priority,
1349 unsigned int max_queue_size,
1350 struct GNUNET_TIME_Relative timeout,
1351 enum GNUNET_BLOCK_Type type,
1352 GNUNET_DATASTORE_DatumProcessor proc,
1355 struct GNUNET_DATASTORE_QueueEntry *qe;
1356 struct GetZeroAnonymityMessage *m;
1357 union QueueContext qc;
1359 GNUNET_assert (NULL != proc);
1360 GNUNET_assert (type != GNUNET_BLOCK_TYPE_ANY);
1361 LOG (GNUNET_ERROR_TYPE_DEBUG,
1362 "Asked to get %llu-th zero-anonymity entry of type %d in %s\n",
1363 (unsigned long long) offset, type,
1364 GNUNET_STRINGS_relative_time_to_string (timeout, GNUNET_YES));
1366 qc.rc.proc_cls = proc_cls;
1367 qe = make_queue_entry (h, sizeof (struct GetZeroAnonymityMessage),
1368 queue_priority, max_queue_size, timeout,
1369 &process_result_message, &qc);
1372 LOG (GNUNET_ERROR_TYPE_DEBUG,
1373 "Could not create queue entry for zero-anonymity procation\n");
1376 GNUNET_STATISTICS_update (h->stats,
1378 ("# GET ZERO ANONYMITY requests executed"), 1,
1380 m = (struct GetZeroAnonymityMessage *) &qe[1];
1381 m->header.type = htons (GNUNET_MESSAGE_TYPE_DATASTORE_GET_ZERO_ANONYMITY);
1382 m->header.size = htons (sizeof (struct GetZeroAnonymityMessage));
1383 m->type = htonl ((uint32_t) type);
1384 m->offset = GNUNET_htonll (offset);
1391 * Get a result for a particular key from the datastore. The processor
1392 * will only be called once.
1394 * @param h handle to the datastore
1395 * @param offset offset of the result (modulo num-results); set to
1396 * a random 64-bit value initially; then increment by
1397 * one each time; detect that all results have been found by uid
1398 * being again the first uid ever returned.
1399 * @param key maybe NULL (to match all entries)
1400 * @param type desired type, 0 for any
1401 * @param queue_priority ranking of this request in the priority queue
1402 * @param max_queue_size at what queue size should this request be dropped
1403 * (if other requests of higher priority are in the queue)
1404 * @param timeout how long to wait at most for a response
1405 * @param proc function to call on each matching value;
1406 * will be called once with a NULL value at the end
1407 * @param proc_cls closure for @a proc
1408 * @return NULL if the entry was not queued, otherwise a handle that can be used to
1411 struct GNUNET_DATASTORE_QueueEntry *
1412 GNUNET_DATASTORE_get_key (struct GNUNET_DATASTORE_Handle *h, uint64_t offset,
1413 const struct GNUNET_HashCode * key,
1414 enum GNUNET_BLOCK_Type type,
1415 unsigned int queue_priority,
1416 unsigned int max_queue_size,
1417 struct GNUNET_TIME_Relative timeout,
1418 GNUNET_DATASTORE_DatumProcessor proc, void *proc_cls)
1420 struct GNUNET_DATASTORE_QueueEntry *qe;
1421 struct GetMessage *gm;
1422 union QueueContext qc;
1424 GNUNET_assert (NULL != proc);
1425 LOG (GNUNET_ERROR_TYPE_DEBUG,
1426 "Asked to look for data of type %u under key `%s'\n",
1427 (unsigned int) type, GNUNET_h2s (key));
1429 qc.rc.proc_cls = proc_cls;
1430 qe = make_queue_entry (h, sizeof (struct GetMessage), queue_priority,
1431 max_queue_size, timeout, &process_result_message, &qc);
1434 LOG (GNUNET_ERROR_TYPE_DEBUG, "Could not queue request for `%s'\n",
1438 #if INSANE_STATISTICS
1439 GNUNET_STATISTICS_update (h->stats, gettext_noop ("# GET requests executed"),
1442 gm = (struct GetMessage *) &qe[1];
1443 gm->header.type = htons (GNUNET_MESSAGE_TYPE_DATASTORE_GET);
1444 gm->type = htonl (type);
1445 gm->offset = GNUNET_htonll (offset);
1448 gm->header.size = htons (sizeof (struct GetMessage));
1454 htons (sizeof (struct GetMessage) - sizeof (struct GNUNET_HashCode));
1462 * Cancel a datastore operation. The final callback from the
1463 * operation must not have been done yet.
1465 * @param qe operation to cancel
1468 GNUNET_DATASTORE_cancel (struct GNUNET_DATASTORE_QueueEntry *qe)
1470 struct GNUNET_DATASTORE_Handle *h;
1472 GNUNET_assert (GNUNET_SYSERR != qe->was_transmitted);
1474 LOG (GNUNET_ERROR_TYPE_DEBUG,
1475 "Pending DATASTORE request %p cancelled (%d, %d)\n", qe,
1476 qe->was_transmitted, h->queue_head == qe);
1477 if (GNUNET_YES == qe->was_transmitted)
1479 free_queue_entry (qe);
1480 h->skip_next_messages++;
1483 free_queue_entry (qe);
1488 /* end of datastore_api.c */