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.
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 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 GNUNET_SCHEDULER_TaskIdentifier 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 GNUNET_SCHEDULER_TaskIdentifier 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 buf
298 * @param buf where to copy the drop message
299 * @return number of bytes written to 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 != GNUNET_SCHEDULER_NO_TASK)
350 GNUNET_SCHEDULER_cancel (h->reconnect_task);
351 h->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
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,
396 qe->task = GNUNET_SCHEDULER_NO_TASK;
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 = GNUNET_SCHEDULER_NO_TASK;
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 (h->client == NULL)
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, const struct GNUNET_MessageHeader *msg)
573 struct GNUNET_DATASTORE_Handle *h = cls;
574 struct GNUNET_DATASTORE_QueueEntry *qe;
576 h->in_receive = GNUNET_NO;
577 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving reply from datastore\n");
578 if (h->skip_next_messages > 0)
580 h->skip_next_messages--;
584 if (NULL == (qe = h->queue_head))
590 qe->response_proc (h, msg);
595 * Transmit request from queue to datastore service.
597 * @param cls the 'struct GNUNET_DATASTORE_Handle'
598 * @param size number of bytes that can be copied to buf
599 * @param buf where to copy the drop message
600 * @return number of bytes written to buf
603 transmit_request (void *cls, size_t size, void *buf)
605 struct GNUNET_DATASTORE_Handle *h = cls;
606 struct GNUNET_DATASTORE_QueueEntry *qe;
610 if (NULL == (qe = h->queue_head))
611 return 0; /* no entry in queue */
614 LOG (GNUNET_ERROR_TYPE_DEBUG, "Failed to transmit request to DATASTORE.\n");
615 GNUNET_STATISTICS_update (h->stats,
616 gettext_noop ("# transmission request failures"),
621 if (size < (msize = qe->message_size))
626 LOG (GNUNET_ERROR_TYPE_DEBUG, "Transmitting %u byte request to DATASTORE\n",
628 memcpy (buf, &qe[1], msize);
629 qe->was_transmitted = GNUNET_YES;
630 GNUNET_SCHEDULER_cancel (qe->task);
631 qe->task = GNUNET_SCHEDULER_NO_TASK;
632 GNUNET_assert (GNUNET_NO == h->in_receive);
633 h->in_receive = GNUNET_YES;
634 GNUNET_CLIENT_receive (h->client, &receive_cb, h,
635 GNUNET_TIME_absolute_get_remaining (qe->timeout));
636 #if INSANE_STATISTICS
637 GNUNET_STATISTICS_update (h->stats,
638 gettext_noop ("# bytes sent to datastore"), 1,
646 * Process entries in the queue (or do nothing if we are already
649 * @param h handle to the datastore
652 process_queue (struct GNUNET_DATASTORE_Handle *h)
654 struct GNUNET_DATASTORE_QueueEntry *qe;
656 if (NULL == (qe = h->queue_head))
658 LOG (GNUNET_ERROR_TYPE_DEBUG, "Queue empty\n");
659 return; /* no entry in queue */
661 if (qe->was_transmitted == GNUNET_YES)
663 LOG (GNUNET_ERROR_TYPE_DEBUG, "Head request already transmitted\n");
664 return; /* waiting for replies */
668 LOG (GNUNET_ERROR_TYPE_DEBUG, "Pending transmission request\n");
669 return; /* request pending */
671 if (h->client == NULL)
673 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not connected\n");
674 return; /* waiting for reconnect */
676 if (GNUNET_YES == h->in_receive)
678 /* wait for response to previous query */
681 LOG (GNUNET_ERROR_TYPE_DEBUG, "Queueing %u byte request to DATASTORE\n",
684 GNUNET_CLIENT_notify_transmit_ready (h->client, qe->message_size,
685 GNUNET_TIME_absolute_get_remaining
686 (qe->timeout), GNUNET_YES,
687 &transmit_request, h);
688 GNUNET_assert (GNUNET_NO == h->in_receive);
689 GNUNET_break (NULL != h->th);
694 * Dummy continuation used to do nothing (but be non-zero).
697 * @param result result
698 * @param min_expiration expiration time
699 * @param emsg error message
702 drop_status_cont (void *cls, int32_t result,
703 struct GNUNET_TIME_Absolute min_expiration,
711 * Free a queue entry. Removes the given entry from the
712 * queue and releases associated resources. Does NOT
715 * @param qe entry to free.
718 free_queue_entry (struct GNUNET_DATASTORE_QueueEntry *qe)
720 struct GNUNET_DATASTORE_Handle *h = qe->h;
722 GNUNET_CONTAINER_DLL_remove (h->queue_head, h->queue_tail, qe);
723 if (qe->task != GNUNET_SCHEDULER_NO_TASK)
725 GNUNET_SCHEDULER_cancel (qe->task);
726 qe->task = GNUNET_SCHEDULER_NO_TASK;
729 qe->was_transmitted = GNUNET_SYSERR; /* use-after-free warning */
735 * Type of a function to call when we receive a message
739 * @param msg message received, NULL on timeout or fatal error
742 process_status_message (void *cls, const struct GNUNET_MessageHeader *msg)
744 struct GNUNET_DATASTORE_Handle *h = cls;
745 struct GNUNET_DATASTORE_QueueEntry *qe;
746 struct StatusContext rc;
747 const struct StatusMessage *sm;
752 if (NULL == (qe = h->queue_head))
761 was_transmitted = qe->was_transmitted;
762 free_queue_entry (qe);
763 if (was_transmitted == GNUNET_YES)
768 rc.cont (rc.cont_cls, GNUNET_SYSERR,
769 GNUNET_TIME_UNIT_ZERO_ABS,
770 _("Failed to receive status response from database."));
773 GNUNET_assert (GNUNET_YES == qe->was_transmitted);
774 free_queue_entry (qe);
775 if ((ntohs (msg->size) < sizeof (struct StatusMessage)) ||
776 (ntohs (msg->type) != GNUNET_MESSAGE_TYPE_DATASTORE_STATUS))
779 h->retry_time = GNUNET_TIME_UNIT_ZERO;
782 rc.cont (rc.cont_cls, GNUNET_SYSERR,
783 GNUNET_TIME_UNIT_ZERO_ABS,
784 _("Error reading response from datastore service"));
787 sm = (const struct StatusMessage *) msg;
788 status = ntohl (sm->status);
790 if (ntohs (msg->size) > sizeof (struct StatusMessage))
792 emsg = (const char *) &sm[1];
793 if (emsg[ntohs (msg->size) - sizeof (struct StatusMessage) - 1] != '\0')
796 emsg = _("Invalid error message received from datastore service");
799 if ((status == GNUNET_SYSERR) && (emsg == NULL))
802 emsg = _("Invalid error message received from datastore service");
804 LOG (GNUNET_ERROR_TYPE_DEBUG, "Received status %d/%s\n", (int) status, emsg);
805 GNUNET_STATISTICS_update (h->stats,
806 gettext_noop ("# status messages received"), 1,
808 h->retry_time = GNUNET_TIME_UNIT_ZERO;
811 rc.cont (rc.cont_cls, status,
812 GNUNET_TIME_absolute_ntoh (sm->min_expiration),
818 * Store an item in the datastore. If the item is already present,
819 * the priorities are summed up and the higher expiration time and
820 * lower anonymity level is used.
822 * @param h handle to the datastore
823 * @param rid reservation ID to use (from "reserve"); use 0 if no
824 * prior reservation was made
825 * @param key key for the value
826 * @param size number of bytes in data
827 * @param data content stored
828 * @param type type of the content
829 * @param priority priority of the content
830 * @param anonymity anonymity-level for the content
831 * @param replication how often should the content be replicated to other peers?
832 * @param expiration expiration time for the content
833 * @param queue_priority ranking of this request in the priority queue
834 * @param max_queue_size at what queue size should this request be dropped
835 * (if other requests of higher priority are in the queue)
836 * @param timeout timeout for the operation
837 * @param cont continuation to call when done
838 * @param cont_cls closure for cont
839 * @return NULL if the entry was not queued, otherwise a handle that can be used to
840 * cancel; note that even if NULL is returned, the callback will be invoked
841 * (or rather, will already have been invoked)
843 struct GNUNET_DATASTORE_QueueEntry *
844 GNUNET_DATASTORE_put (struct GNUNET_DATASTORE_Handle *h, uint32_t rid,
845 const struct GNUNET_HashCode * key, size_t size,
846 const void *data, enum GNUNET_BLOCK_Type type,
847 uint32_t priority, uint32_t anonymity,
848 uint32_t replication,
849 struct GNUNET_TIME_Absolute expiration,
850 unsigned int queue_priority, unsigned int max_queue_size,
851 struct GNUNET_TIME_Relative timeout,
852 GNUNET_DATASTORE_ContinuationWithStatus cont,
855 struct GNUNET_DATASTORE_QueueEntry *qe;
856 struct DataMessage *dm;
858 union QueueContext qc;
860 LOG (GNUNET_ERROR_TYPE_DEBUG,
861 "Asked to put %u bytes of data under key `%s' for %s\n", size,
863 GNUNET_STRINGS_relative_time_to_string (GNUNET_TIME_absolute_get_remaining (expiration),
865 msize = sizeof (struct DataMessage) + size;
866 GNUNET_assert (msize < GNUNET_SERVER_MAX_MESSAGE_SIZE);
868 qc.sc.cont_cls = cont_cls;
869 qe = make_queue_entry (h, msize, queue_priority, max_queue_size, timeout,
870 &process_status_message, &qc);
873 LOG (GNUNET_ERROR_TYPE_DEBUG, "Could not create queue entry for PUT\n");
876 GNUNET_STATISTICS_update (h->stats, gettext_noop ("# PUT requests executed"),
878 dm = (struct DataMessage *) &qe[1];
879 dm->header.type = htons (GNUNET_MESSAGE_TYPE_DATASTORE_PUT);
880 dm->header.size = htons (msize);
881 dm->rid = htonl (rid);
882 dm->size = htonl ((uint32_t) size);
883 dm->type = htonl (type);
884 dm->priority = htonl (priority);
885 dm->anonymity = htonl (anonymity);
886 dm->replication = htonl (replication);
887 dm->reserved = htonl (0);
888 dm->uid = GNUNET_htonll (0);
889 dm->expiration = GNUNET_TIME_absolute_hton (expiration);
891 memcpy (&dm[1], data, size);
898 * Reserve space in the datastore. This function should be used
899 * to avoid "out of space" failures during a longer sequence of "put"
900 * operations (for example, when a file is being inserted).
902 * @param h handle to the datastore
903 * @param amount how much space (in bytes) should be reserved (for content only)
904 * @param entries how many entries will be created (to calculate per-entry overhead)
905 * @param queue_priority ranking of this request in the priority queue
906 * @param max_queue_size at what queue size should this request be dropped
907 * (if other requests of higher priority are in the queue)
908 * @param timeout how long to wait at most for a response (or before dying in queue)
909 * @param cont continuation to call when done; "success" will be set to
910 * a positive reservation value if space could be reserved.
911 * @param cont_cls closure for cont
912 * @return NULL if the entry was not queued, otherwise a handle that can be used to
913 * cancel; note that even if NULL is returned, the callback will be invoked
914 * (or rather, will already have been invoked)
916 struct GNUNET_DATASTORE_QueueEntry *
917 GNUNET_DATASTORE_reserve (struct GNUNET_DATASTORE_Handle *h, uint64_t amount,
918 uint32_t entries, unsigned int queue_priority,
919 unsigned int max_queue_size,
920 struct GNUNET_TIME_Relative timeout,
921 GNUNET_DATASTORE_ContinuationWithStatus cont,
924 struct GNUNET_DATASTORE_QueueEntry *qe;
925 struct ReserveMessage *rm;
926 union QueueContext qc;
929 cont = &drop_status_cont;
930 LOG (GNUNET_ERROR_TYPE_DEBUG,
931 "Asked to reserve %llu bytes of data and %u entries\n",
932 (unsigned long long) amount, (unsigned int) entries);
934 qc.sc.cont_cls = cont_cls;
935 qe = make_queue_entry (h, sizeof (struct ReserveMessage), queue_priority,
936 max_queue_size, timeout, &process_status_message, &qc);
939 LOG (GNUNET_ERROR_TYPE_DEBUG, "Could not create queue entry to reserve\n");
942 GNUNET_STATISTICS_update (h->stats,
943 gettext_noop ("# RESERVE requests executed"), 1,
945 rm = (struct ReserveMessage *) &qe[1];
946 rm->header.type = htons (GNUNET_MESSAGE_TYPE_DATASTORE_RESERVE);
947 rm->header.size = htons (sizeof (struct ReserveMessage));
948 rm->entries = htonl (entries);
949 rm->amount = GNUNET_htonll (amount);
956 * Signal that all of the data for which a reservation was made has
957 * been stored and that whatever excess space might have been reserved
958 * can now be released.
960 * @param h handle to the datastore
961 * @param rid reservation ID (value of "success" in original continuation
962 * from the "reserve" function).
963 * @param queue_priority ranking of this request in the priority queue
964 * @param max_queue_size at what queue size should this request be dropped
965 * (if other requests of higher priority are in the queue)
966 * @param queue_priority ranking of this request in the priority queue
967 * @param max_queue_size at what queue size should this request be dropped
968 * (if other requests of higher priority are in the queue)
969 * @param timeout how long to wait at most for a response
970 * @param cont continuation to call when done
971 * @param cont_cls closure for cont
972 * @return NULL if the entry was not queued, otherwise a handle that can be used to
973 * cancel; note that even if NULL is returned, the callback will be invoked
974 * (or rather, will already have been invoked)
976 struct GNUNET_DATASTORE_QueueEntry *
977 GNUNET_DATASTORE_release_reserve (struct GNUNET_DATASTORE_Handle *h,
978 uint32_t rid, unsigned int queue_priority,
979 unsigned int max_queue_size,
980 struct GNUNET_TIME_Relative timeout,
981 GNUNET_DATASTORE_ContinuationWithStatus cont,
984 struct GNUNET_DATASTORE_QueueEntry *qe;
985 struct ReleaseReserveMessage *rrm;
986 union QueueContext qc;
989 cont = &drop_status_cont;
990 LOG (GNUNET_ERROR_TYPE_DEBUG, "Asked to release reserve %d\n", rid);
992 qc.sc.cont_cls = cont_cls;
993 qe = make_queue_entry (h, sizeof (struct ReleaseReserveMessage),
994 queue_priority, max_queue_size, timeout,
995 &process_status_message, &qc);
998 LOG (GNUNET_ERROR_TYPE_DEBUG,
999 "Could not create queue entry to release reserve\n");
1002 GNUNET_STATISTICS_update (h->stats,
1004 ("# RELEASE RESERVE requests executed"), 1,
1006 rrm = (struct ReleaseReserveMessage *) &qe[1];
1007 rrm->header.type = htons (GNUNET_MESSAGE_TYPE_DATASTORE_RELEASE_RESERVE);
1008 rrm->header.size = htons (sizeof (struct ReleaseReserveMessage));
1009 rrm->rid = htonl (rid);
1016 * Update a value in the datastore.
1018 * @param h handle to the datastore
1019 * @param uid identifier for the value
1020 * @param priority how much to increase the priority of the value
1021 * @param expiration new expiration value should be MAX of existing and this argument
1022 * @param queue_priority ranking of this request in the priority queue
1023 * @param max_queue_size at what queue size should this request be dropped
1024 * (if other requests of higher priority are in the queue)
1025 * @param timeout how long to wait at most for a response
1026 * @param cont continuation to call when done
1027 * @param cont_cls closure for cont
1028 * @return NULL if the entry was not queued, otherwise a handle that can be used to
1029 * cancel; note that even if NULL is returned, the callback will be invoked
1030 * (or rather, will already have been invoked)
1032 struct GNUNET_DATASTORE_QueueEntry *
1033 GNUNET_DATASTORE_update (struct GNUNET_DATASTORE_Handle *h, uint64_t uid,
1035 struct GNUNET_TIME_Absolute expiration,
1036 unsigned int queue_priority,
1037 unsigned int max_queue_size,
1038 struct GNUNET_TIME_Relative timeout,
1039 GNUNET_DATASTORE_ContinuationWithStatus cont,
1042 struct GNUNET_DATASTORE_QueueEntry *qe;
1043 struct UpdateMessage *um;
1044 union QueueContext qc;
1047 cont = &drop_status_cont;
1048 LOG (GNUNET_ERROR_TYPE_DEBUG,
1049 "Asked to update entry %llu raising priority by %u and expiration to %s\n",
1051 (unsigned int) priority,
1052 GNUNET_STRINGS_absolute_time_to_string (expiration));
1054 qc.sc.cont_cls = cont_cls;
1055 qe = make_queue_entry (h, sizeof (struct UpdateMessage), queue_priority,
1056 max_queue_size, timeout, &process_status_message, &qc);
1059 LOG (GNUNET_ERROR_TYPE_DEBUG, "Could not create queue entry for UPDATE\n");
1062 GNUNET_STATISTICS_update (h->stats,
1063 gettext_noop ("# UPDATE requests executed"), 1,
1065 um = (struct UpdateMessage *) &qe[1];
1066 um->header.type = htons (GNUNET_MESSAGE_TYPE_DATASTORE_UPDATE);
1067 um->header.size = htons (sizeof (struct UpdateMessage));
1068 um->priority = htonl (priority);
1069 um->expiration = GNUNET_TIME_absolute_hton (expiration);
1070 um->uid = GNUNET_htonll (uid);
1077 * Explicitly remove some content from the database.
1078 * The "cont"inuation will be called with status
1079 * "GNUNET_OK" if content was removed, "GNUNET_NO"
1080 * if no matching entry was found and "GNUNET_SYSERR"
1081 * on all other types of errors.
1083 * @param h handle to the datastore
1084 * @param key key for the value
1085 * @param size number of bytes in data
1086 * @param data content stored
1087 * @param queue_priority ranking of this request in the priority queue
1088 * @param max_queue_size at what queue size should this request be dropped
1089 * (if other requests of higher priority are in the queue)
1090 * @param timeout how long to wait at most for a response
1091 * @param cont continuation to call when done
1092 * @param cont_cls closure for cont
1093 * @return NULL if the entry was not queued, otherwise a handle that can be used to
1094 * cancel; note that even if NULL is returned, the callback will be invoked
1095 * (or rather, will already have been invoked)
1097 struct GNUNET_DATASTORE_QueueEntry *
1098 GNUNET_DATASTORE_remove (struct GNUNET_DATASTORE_Handle *h,
1099 const struct GNUNET_HashCode * key, size_t size,
1100 const void *data, unsigned int queue_priority,
1101 unsigned int max_queue_size,
1102 struct GNUNET_TIME_Relative timeout,
1103 GNUNET_DATASTORE_ContinuationWithStatus cont,
1106 struct GNUNET_DATASTORE_QueueEntry *qe;
1107 struct DataMessage *dm;
1109 union QueueContext qc;
1112 cont = &drop_status_cont;
1113 LOG (GNUNET_ERROR_TYPE_DEBUG, "Asked to remove %u bytes under key `%s'\n",
1114 size, GNUNET_h2s (key));
1116 qc.sc.cont_cls = cont_cls;
1117 msize = sizeof (struct DataMessage) + size;
1118 GNUNET_assert (msize < GNUNET_SERVER_MAX_MESSAGE_SIZE);
1119 qe = make_queue_entry (h, msize, queue_priority, max_queue_size, timeout,
1120 &process_status_message, &qc);
1123 LOG (GNUNET_ERROR_TYPE_DEBUG, "Could not create queue entry for REMOVE\n");
1126 GNUNET_STATISTICS_update (h->stats,
1127 gettext_noop ("# REMOVE requests executed"), 1,
1129 dm = (struct DataMessage *) &qe[1];
1130 dm->header.type = htons (GNUNET_MESSAGE_TYPE_DATASTORE_REMOVE);
1131 dm->header.size = htons (msize);
1132 dm->rid = htonl (0);
1133 dm->size = htonl (size);
1134 dm->type = htonl (0);
1135 dm->priority = htonl (0);
1136 dm->anonymity = htonl (0);
1137 dm->uid = GNUNET_htonll (0);
1138 dm->expiration = GNUNET_TIME_absolute_hton (GNUNET_TIME_UNIT_ZERO_ABS);
1140 memcpy (&dm[1], data, size);
1147 * Type of a function to call when we receive a message
1150 * @param cls closure
1151 * @param msg message received, NULL on timeout or fatal error
1154 process_result_message (void *cls, const struct GNUNET_MessageHeader *msg)
1156 struct GNUNET_DATASTORE_Handle *h = cls;
1157 struct GNUNET_DATASTORE_QueueEntry *qe;
1158 struct ResultContext rc;
1159 const struct DataMessage *dm;
1160 int was_transmitted;
1165 GNUNET_assert (NULL != qe);
1167 was_transmitted = qe->was_transmitted;
1168 free_queue_entry (qe);
1169 if (GNUNET_YES == was_transmitted)
1171 LOG (GNUNET_ERROR_TYPE_WARNING,
1172 _("Failed to receive response from database.\n"));
1179 if (NULL != rc.proc)
1180 rc.proc (rc.proc_cls, NULL, 0, NULL, 0, 0, 0, GNUNET_TIME_UNIT_ZERO_ABS,
1184 if (ntohs (msg->type) == GNUNET_MESSAGE_TYPE_DATASTORE_DATA_END)
1186 GNUNET_break (ntohs (msg->size) == sizeof (struct GNUNET_MessageHeader));
1189 GNUNET_assert (GNUNET_YES == qe->was_transmitted);
1190 free_queue_entry (qe);
1191 LOG (GNUNET_ERROR_TYPE_DEBUG,
1192 "Received end of result set, new queue size is %u\n", h->queue_size);
1193 h->retry_time = GNUNET_TIME_UNIT_ZERO;
1194 h->result_count = 0;
1196 if (NULL != rc.proc)
1197 rc.proc (rc.proc_cls, NULL, 0, NULL, 0, 0, 0, GNUNET_TIME_UNIT_ZERO_ABS,
1202 GNUNET_assert (NULL != qe);
1204 if (GNUNET_YES != qe->was_transmitted)
1207 free_queue_entry (qe);
1208 h->retry_time = GNUNET_TIME_UNIT_ZERO;
1210 if (rc.proc != NULL)
1211 rc.proc (rc.proc_cls, NULL, 0, NULL, 0, 0, 0, GNUNET_TIME_UNIT_ZERO_ABS,
1215 if ((ntohs (msg->size) < sizeof (struct DataMessage)) ||
1216 (ntohs (msg->type) != GNUNET_MESSAGE_TYPE_DATASTORE_DATA) ||
1217 (ntohs (msg->size) !=
1218 sizeof (struct DataMessage) +
1219 ntohl (((const struct DataMessage *) msg)->size)))
1222 free_queue_entry (qe);
1223 h->retry_time = GNUNET_TIME_UNIT_ZERO;
1225 if (rc.proc != NULL)
1226 rc.proc (rc.proc_cls, NULL, 0, NULL, 0, 0, 0, GNUNET_TIME_UNIT_ZERO_ABS,
1230 #if INSANE_STATISTICS
1231 GNUNET_STATISTICS_update (h->stats, gettext_noop ("# Results received"), 1,
1234 dm = (const struct DataMessage *) msg;
1235 LOG (GNUNET_ERROR_TYPE_DEBUG,
1236 "Received result %llu with type %u and size %u with key %s\n",
1237 (unsigned long long) GNUNET_ntohll (dm->uid), ntohl (dm->type),
1238 ntohl (dm->size), GNUNET_h2s (&dm->key));
1239 free_queue_entry (qe);
1240 h->retry_time = GNUNET_TIME_UNIT_ZERO;
1242 if (rc.proc != NULL)
1243 rc.proc (rc.proc_cls, &dm->key, ntohl (dm->size), &dm[1], ntohl (dm->type),
1244 ntohl (dm->priority), ntohl (dm->anonymity),
1245 GNUNET_TIME_absolute_ntoh (dm->expiration),
1246 GNUNET_ntohll (dm->uid));
1251 * Get a random value from the datastore for content replication.
1252 * Returns a single, random value among those with the highest
1253 * replication score, lowering positive replication scores by one for
1254 * the chosen value (if only content with a replication score exists,
1255 * a random value is returned and replication scores are not changed).
1257 * @param h handle to the datastore
1258 * @param queue_priority ranking of this request in the priority queue
1259 * @param max_queue_size at what queue size should this request be dropped
1260 * (if other requests of higher priority are in the queue)
1261 * @param timeout how long to wait at most for a response
1262 * @param proc function to call on a random value; it
1263 * will be called once with a value (if available)
1264 * and always once with a value of NULL.
1265 * @param proc_cls closure for proc
1266 * @return NULL if the entry was not queued, otherwise a handle that can be used to
1269 struct GNUNET_DATASTORE_QueueEntry *
1270 GNUNET_DATASTORE_get_for_replication (struct GNUNET_DATASTORE_Handle *h,
1271 unsigned int queue_priority,
1272 unsigned int max_queue_size,
1273 struct GNUNET_TIME_Relative timeout,
1274 GNUNET_DATASTORE_DatumProcessor proc,
1277 struct GNUNET_DATASTORE_QueueEntry *qe;
1278 struct GNUNET_MessageHeader *m;
1279 union QueueContext qc;
1281 GNUNET_assert (NULL != proc);
1282 LOG (GNUNET_ERROR_TYPE_DEBUG,
1283 "Asked to get replication entry in %s\n",
1284 GNUNET_STRINGS_relative_time_to_string (timeout, GNUNET_YES));
1286 qc.rc.proc_cls = proc_cls;
1287 qe = make_queue_entry (h, sizeof (struct GNUNET_MessageHeader),
1288 queue_priority, max_queue_size, timeout,
1289 &process_result_message, &qc);
1292 LOG (GNUNET_ERROR_TYPE_DEBUG,
1293 "Could not create queue entry for GET REPLICATION\n");
1296 GNUNET_STATISTICS_update (h->stats,
1298 ("# GET REPLICATION requests executed"), 1,
1300 m = (struct GNUNET_MessageHeader *) &qe[1];
1301 m->type = htons (GNUNET_MESSAGE_TYPE_DATASTORE_GET_REPLICATION);
1302 m->size = htons (sizeof (struct GNUNET_MessageHeader));
1309 * Get a single zero-anonymity value from the datastore.
1311 * @param h handle to the datastore
1312 * @param offset offset of the result (modulo num-results); set to
1313 * a random 64-bit value initially; then increment by
1314 * one each time; detect that all results have been found by uid
1315 * being again the first uid ever returned.
1316 * @param queue_priority ranking of this request in the priority queue
1317 * @param max_queue_size at what queue size should this request be dropped
1318 * (if other requests of higher priority are in the queue)
1319 * @param timeout how long to wait at most for a response
1320 * @param type allowed type for the operation (never zero)
1321 * @param proc function to call on a random value; it
1322 * will be called once with a value (if available)
1323 * or with NULL if none value exists.
1324 * @param proc_cls closure for proc
1325 * @return NULL if the entry was not queued, otherwise a handle that can be used to
1328 struct GNUNET_DATASTORE_QueueEntry *
1329 GNUNET_DATASTORE_get_zero_anonymity (struct GNUNET_DATASTORE_Handle *h,
1331 unsigned int queue_priority,
1332 unsigned int max_queue_size,
1333 struct GNUNET_TIME_Relative timeout,
1334 enum GNUNET_BLOCK_Type type,
1335 GNUNET_DATASTORE_DatumProcessor proc,
1338 struct GNUNET_DATASTORE_QueueEntry *qe;
1339 struct GetZeroAnonymityMessage *m;
1340 union QueueContext qc;
1342 GNUNET_assert (NULL != proc);
1343 GNUNET_assert (type != GNUNET_BLOCK_TYPE_ANY);
1344 LOG (GNUNET_ERROR_TYPE_DEBUG,
1345 "Asked to get %llu-th zero-anonymity entry of type %d in %s\n",
1346 (unsigned long long) offset, type,
1347 GNUNET_STRINGS_relative_time_to_string (timeout, GNUNET_YES));
1349 qc.rc.proc_cls = proc_cls;
1350 qe = make_queue_entry (h, sizeof (struct GetZeroAnonymityMessage),
1351 queue_priority, max_queue_size, timeout,
1352 &process_result_message, &qc);
1355 LOG (GNUNET_ERROR_TYPE_DEBUG,
1356 "Could not create queue entry for zero-anonymity procation\n");
1359 GNUNET_STATISTICS_update (h->stats,
1361 ("# GET ZERO ANONYMITY requests executed"), 1,
1363 m = (struct GetZeroAnonymityMessage *) &qe[1];
1364 m->header.type = htons (GNUNET_MESSAGE_TYPE_DATASTORE_GET_ZERO_ANONYMITY);
1365 m->header.size = htons (sizeof (struct GetZeroAnonymityMessage));
1366 m->type = htonl ((uint32_t) type);
1367 m->offset = GNUNET_htonll (offset);
1374 * Get a result for a particular key from the datastore. The processor
1375 * will only be called once.
1377 * @param h handle to the datastore
1378 * @param offset offset of the result (modulo num-results); set to
1379 * a random 64-bit value initially; then increment by
1380 * one each time; detect that all results have been found by uid
1381 * being again the first uid ever returned.
1382 * @param key maybe NULL (to match all entries)
1383 * @param type desired type, 0 for any
1384 * @param queue_priority ranking of this request in the priority queue
1385 * @param max_queue_size at what queue size should this request be dropped
1386 * (if other requests of higher priority are in the queue)
1387 * @param timeout how long to wait at most for a response
1388 * @param proc function to call on each matching value;
1389 * will be called once with a NULL value at the end
1390 * @param proc_cls closure for proc
1391 * @return NULL if the entry was not queued, otherwise a handle that can be used to
1394 struct GNUNET_DATASTORE_QueueEntry *
1395 GNUNET_DATASTORE_get_key (struct GNUNET_DATASTORE_Handle *h, uint64_t offset,
1396 const struct GNUNET_HashCode * key,
1397 enum GNUNET_BLOCK_Type type,
1398 unsigned int queue_priority,
1399 unsigned int max_queue_size,
1400 struct GNUNET_TIME_Relative timeout,
1401 GNUNET_DATASTORE_DatumProcessor proc, void *proc_cls)
1403 struct GNUNET_DATASTORE_QueueEntry *qe;
1404 struct GetMessage *gm;
1405 union QueueContext qc;
1407 GNUNET_assert (NULL != proc);
1408 LOG (GNUNET_ERROR_TYPE_DEBUG,
1409 "Asked to look for data of type %u under key `%s'\n",
1410 (unsigned int) type, GNUNET_h2s (key));
1412 qc.rc.proc_cls = proc_cls;
1413 qe = make_queue_entry (h, sizeof (struct GetMessage), queue_priority,
1414 max_queue_size, timeout, &process_result_message, &qc);
1417 LOG (GNUNET_ERROR_TYPE_DEBUG, "Could not queue request for `%s'\n",
1421 #if INSANE_STATISTICS
1422 GNUNET_STATISTICS_update (h->stats, gettext_noop ("# GET requests executed"),
1425 gm = (struct GetMessage *) &qe[1];
1426 gm->header.type = htons (GNUNET_MESSAGE_TYPE_DATASTORE_GET);
1427 gm->type = htonl (type);
1428 gm->offset = GNUNET_htonll (offset);
1431 gm->header.size = htons (sizeof (struct GetMessage));
1437 htons (sizeof (struct GetMessage) - sizeof (struct GNUNET_HashCode));
1445 * Cancel a datastore operation. The final callback from the
1446 * operation must not have been done yet.
1448 * @param qe operation to cancel
1451 GNUNET_DATASTORE_cancel (struct GNUNET_DATASTORE_QueueEntry *qe)
1453 struct GNUNET_DATASTORE_Handle *h;
1455 GNUNET_assert (GNUNET_SYSERR != qe->was_transmitted);
1457 LOG (GNUNET_ERROR_TYPE_DEBUG,
1458 "Pending DATASTORE request %p cancelled (%d, %d)\n", qe,
1459 qe->was_transmitted, h->queue_head == qe);
1460 if (GNUNET_YES == qe->was_transmitted)
1462 free_queue_entry (qe);
1463 h->skip_next_messages++;
1466 free_queue_entry (qe);
1471 /* end of datastore_api.c */