2 This file is part of GNUnet
3 (C) 2004, 2005, 2006, 2007, 2009, 2010, 2011 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 * If a client stopped asking for more results, how many more do
38 * we receive from the DB before killing the connection? Trade-off
39 * between re-doing TCP handshakes and (needlessly) receiving
42 #define MAX_EXCESS_RESULTS 8
45 * Context for processing status messages.
50 * Continuation to call with the status.
52 GNUNET_DATASTORE_ContinuationWithStatus cont;
63 * Context for processing result messages.
68 * Function to call with the result.
70 GNUNET_DATASTORE_DatumProcessor proc;
81 * Context for a queue operation.
86 struct StatusContext sc;
88 struct ResultContext rc;
95 * Entry in our priority queue.
97 struct GNUNET_DATASTORE_QueueEntry
101 * This is a linked list.
103 struct GNUNET_DATASTORE_QueueEntry *next;
106 * This is a linked list.
108 struct GNUNET_DATASTORE_QueueEntry *prev;
111 * Handle to the master context.
113 struct GNUNET_DATASTORE_Handle *h;
116 * Response processor (NULL if we are not waiting for a response).
117 * This struct should be used for the closure, function-specific
118 * arguments can be passed via 'qc'.
120 GNUNET_CLIENT_MessageHandler response_proc;
123 * Function to call after transmission of the request.
125 GNUNET_DATASTORE_ContinuationWithStatus cont;
128 * Closure for 'cont'.
133 * Context for the operation.
135 union QueueContext qc;
138 * Task for timeout signalling.
140 GNUNET_SCHEDULER_TaskIdentifier task;
143 * Timeout for the current operation.
145 struct GNUNET_TIME_Absolute timeout;
148 * Priority in the queue.
150 unsigned int priority;
153 * Maximum allowed length of queue (otherwise
154 * this request should be discarded).
156 unsigned int max_queue;
159 * Number of bytes in the request message following
160 * this struct. 32-bit value for nicer memory
161 * access (and overall struct alignment).
163 uint32_t message_size;
166 * Has this message been transmitted to the service?
167 * Only ever GNUNET_YES for the head of the queue.
168 * Note that the overall struct should end at a
169 * multiple of 64 bits.
176 * Handle to the datastore service.
178 struct GNUNET_DATASTORE_Handle
184 const struct GNUNET_CONFIGURATION_Handle *cfg;
187 * Current connection to the datastore service.
189 struct GNUNET_CLIENT_Connection *client;
192 * Handle for statistics.
194 struct GNUNET_STATISTICS_Handle *stats;
197 * Current transmit handle.
199 struct GNUNET_CLIENT_TransmitHandle *th;
202 * Current head of priority queue.
204 struct GNUNET_DATASTORE_QueueEntry *queue_head;
207 * Current tail of priority queue.
209 struct GNUNET_DATASTORE_QueueEntry *queue_tail;
212 * Task for trying to reconnect.
214 GNUNET_SCHEDULER_TaskIdentifier reconnect_task;
217 * How quickly should we retry? Used for exponential back-off on
220 struct GNUNET_TIME_Relative retry_time;
223 * Number of entries in the queue.
225 unsigned int queue_size;
228 * Number of results we're receiving for the current query
229 * after application stopped to care. Used to determine when
230 * to reset the connection.
232 unsigned int result_count;
235 * Are we currently trying to receive from the service?
240 * We should ignore the next message(s) from the service.
242 unsigned int skip_next_messages;
249 * Connect to the datastore service.
251 * @param cfg configuration to use
252 * @return handle to use to access the service
254 struct GNUNET_DATASTORE_Handle *
255 GNUNET_DATASTORE_connect (const struct GNUNET_CONFIGURATION_Handle *cfg)
257 struct GNUNET_CLIENT_Connection *c;
258 struct GNUNET_DATASTORE_Handle *h;
260 c = GNUNET_CLIENT_connect ("datastore", cfg);
262 return NULL; /* oops */
263 h = GNUNET_malloc (sizeof (struct GNUNET_DATASTORE_Handle) +
264 GNUNET_SERVER_MAX_MESSAGE_SIZE - 1);
267 h->stats = GNUNET_STATISTICS_create ("datastore-api", cfg);
273 * Transmit DROP message to datastore service.
275 * @param cls the 'struct GNUNET_DATASTORE_Handle'
276 * @param size number of bytes that can be copied to buf
277 * @param buf where to copy the drop message
278 * @return number of bytes written to buf
281 transmit_drop (void *cls, size_t size, void *buf)
283 struct GNUNET_DATASTORE_Handle *h = cls;
284 struct GNUNET_MessageHeader *hdr;
288 LOG (GNUNET_ERROR_TYPE_WARNING,
289 _("Failed to transmit request to drop database.\n"));
290 GNUNET_DATASTORE_disconnect (h, GNUNET_NO);
293 GNUNET_assert (size >= sizeof (struct GNUNET_MessageHeader));
295 hdr->size = htons (sizeof (struct GNUNET_MessageHeader));
296 hdr->type = htons (GNUNET_MESSAGE_TYPE_DATASTORE_DROP);
297 GNUNET_DATASTORE_disconnect (h, GNUNET_NO);
298 return sizeof (struct GNUNET_MessageHeader);
303 * Disconnect from the datastore service (and free
304 * associated resources).
306 * @param h handle to the datastore
307 * @param drop set to GNUNET_YES to delete all data in datastore (!)
310 GNUNET_DATASTORE_disconnect (struct GNUNET_DATASTORE_Handle *h, int drop)
312 struct GNUNET_DATASTORE_QueueEntry *qe;
315 LOG (GNUNET_ERROR_TYPE_DEBUG, "Datastore disconnect\n");
319 GNUNET_CLIENT_notify_transmit_ready_cancel (h->th);
322 if (h->client != NULL)
324 GNUNET_CLIENT_disconnect (h->client, GNUNET_NO);
327 if (h->reconnect_task != GNUNET_SCHEDULER_NO_TASK)
329 GNUNET_SCHEDULER_cancel (h->reconnect_task);
330 h->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
332 while (NULL != (qe = h->queue_head))
334 GNUNET_assert (NULL != qe->response_proc);
335 qe->response_proc (h, NULL);
337 if (GNUNET_YES == drop)
339 h->client = GNUNET_CLIENT_connect ("datastore", h->cfg);
340 if (h->client != NULL)
343 GNUNET_CLIENT_notify_transmit_ready (h->client,
345 GNUNET_MessageHeader),
346 GNUNET_TIME_UNIT_MINUTES,
347 GNUNET_YES, &transmit_drop, h))
349 GNUNET_CLIENT_disconnect (h->client, GNUNET_NO);
354 GNUNET_STATISTICS_destroy (h->stats, GNUNET_NO);
361 * A request has timed out (before being transmitted to the service).
363 * @param cls the 'struct GNUNET_DATASTORE_QueueEntry'
364 * @param tc scheduler context
367 timeout_queue_entry (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
369 struct GNUNET_DATASTORE_QueueEntry *qe = cls;
371 GNUNET_STATISTICS_update (qe->h->stats,
372 gettext_noop ("# queue entry timeouts"), 1,
374 qe->task = GNUNET_SCHEDULER_NO_TASK;
375 GNUNET_assert (qe->was_transmitted == GNUNET_NO);
377 LOG (GNUNET_ERROR_TYPE_DEBUG, "Timeout of request in datastore queue\n");
379 qe->response_proc (qe->h, NULL);
384 * Create a new entry for our priority queue (and possibly discard other entires if
385 * the queue is getting too long).
387 * @param h handle to the datastore
388 * @param msize size of the message to queue
389 * @param queue_priority priority of the entry
390 * @param max_queue_size at what queue size should this request be dropped
391 * (if other requests of higher priority are in the queue)
392 * @param timeout timeout for the operation
393 * @param response_proc function to call with replies (can be NULL)
394 * @param qc client context (NOT a closure for response_proc)
395 * @return NULL if the queue is full
397 static struct GNUNET_DATASTORE_QueueEntry *
398 make_queue_entry (struct GNUNET_DATASTORE_Handle *h, size_t msize,
399 unsigned int queue_priority, unsigned int max_queue_size,
400 struct GNUNET_TIME_Relative timeout,
401 GNUNET_CLIENT_MessageHandler response_proc,
402 const union QueueContext *qc)
404 struct GNUNET_DATASTORE_QueueEntry *ret;
405 struct GNUNET_DATASTORE_QueueEntry *pos;
410 while ((pos != NULL) && (c < max_queue_size) &&
411 (pos->priority >= queue_priority))
416 if (c >= max_queue_size)
418 GNUNET_STATISTICS_update (h->stats, gettext_noop ("# queue overflows"), 1,
422 ret = GNUNET_malloc (sizeof (struct GNUNET_DATASTORE_QueueEntry) + msize);
424 ret->response_proc = response_proc;
426 ret->timeout = GNUNET_TIME_relative_to_absolute (timeout);
427 ret->priority = queue_priority;
428 ret->max_queue = max_queue_size;
429 ret->message_size = msize;
430 ret->was_transmitted = GNUNET_NO;
433 /* append at the tail */
439 /* do not insert at HEAD if HEAD query was already
440 * transmitted and we are still receiving replies! */
441 if ((pos == NULL) && (h->queue_head->was_transmitted))
445 GNUNET_STATISTICS_update (h->stats, gettext_noop ("# queue entries created"),
447 GNUNET_CONTAINER_DLL_insert_after (h->queue_head, h->queue_tail, pos, ret);
449 ret->task = GNUNET_SCHEDULER_add_delayed (timeout, &timeout_queue_entry, ret);
453 if ((pos->max_queue < h->queue_size) && (pos->was_transmitted == GNUNET_NO))
455 GNUNET_assert (pos->response_proc != NULL);
456 /* move 'pos' element to head so that it will be
457 * killed on 'NULL' call below */
459 LOG (GNUNET_ERROR_TYPE_DEBUG, "Dropping request from datastore queue\n");
461 GNUNET_CONTAINER_DLL_remove (h->queue_head, h->queue_tail, pos);
462 GNUNET_CONTAINER_DLL_insert (h->queue_head, h->queue_tail, pos);
463 GNUNET_STATISTICS_update (h->stats,
465 ("# Requests dropped from datastore queue"), 1,
467 GNUNET_assert (h->queue_head == pos);
468 pos->response_proc (h, NULL);
478 * Process entries in the queue (or do nothing if we are already
481 * @param h handle to the datastore
484 process_queue (struct GNUNET_DATASTORE_Handle *h);
488 * Try reconnecting to the datastore service.
490 * @param cls the 'struct GNUNET_DATASTORE_Handle'
491 * @param tc scheduler context
494 try_reconnect (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
496 struct GNUNET_DATASTORE_Handle *h = cls;
498 if (h->retry_time.rel_value < GNUNET_CONSTANTS_SERVICE_RETRY.rel_value)
499 h->retry_time = GNUNET_CONSTANTS_SERVICE_RETRY;
501 h->retry_time = GNUNET_TIME_relative_multiply (h->retry_time, 2);
502 if (h->retry_time.rel_value > GNUNET_CONSTANTS_SERVICE_TIMEOUT.rel_value)
503 h->retry_time = GNUNET_CONSTANTS_SERVICE_TIMEOUT;
504 h->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
505 h->client = GNUNET_CLIENT_connect ("datastore", h->cfg);
506 if (h->client == NULL)
508 LOG (GNUNET_ERROR_TYPE_ERROR, "DATASTORE reconnect failed (fatally)\n");
511 GNUNET_STATISTICS_update (h->stats,
513 ("# datastore connections (re)created"), 1,
516 LOG (GNUNET_ERROR_TYPE_DEBUG, "Reconnected to DATASTORE\n");
523 * Disconnect from the service and then try reconnecting to the datastore service
526 * @param h handle to datastore to disconnect and reconnect
529 do_disconnect (struct GNUNET_DATASTORE_Handle *h)
531 if (h->client == NULL)
534 LOG (GNUNET_ERROR_TYPE_DEBUG,
535 "client NULL in disconnect, will not try to reconnect\n");
540 GNUNET_STATISTICS_update (stats, gettext_noop ("# reconnected to DATASTORE"),
543 GNUNET_CLIENT_disconnect (h->client, GNUNET_NO);
544 h->skip_next_messages = 0;
547 GNUNET_SCHEDULER_add_delayed (h->retry_time, &try_reconnect, h);
552 * Function called whenever we receive a message from
553 * the service. Calls the appropriate handler.
555 * @param cls the 'struct GNUNET_DATASTORE_Handle'
556 * @param msg the received message
559 receive_cb (void *cls, const struct GNUNET_MessageHeader *msg)
561 struct GNUNET_DATASTORE_Handle *h = cls;
562 struct GNUNET_DATASTORE_QueueEntry *qe;
564 h->in_receive = GNUNET_NO;
566 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving reply from datastore\n");
568 if (h->skip_next_messages > 0)
570 h->skip_next_messages--;
574 if (NULL == (qe = h->queue_head))
580 qe->response_proc (h, msg);
585 * Transmit request from queue to datastore service.
587 * @param cls the 'struct GNUNET_DATASTORE_Handle'
588 * @param size number of bytes that can be copied to buf
589 * @param buf where to copy the drop message
590 * @return number of bytes written to buf
593 transmit_request (void *cls, size_t size, void *buf)
595 struct GNUNET_DATASTORE_Handle *h = cls;
596 struct GNUNET_DATASTORE_QueueEntry *qe;
600 if (NULL == (qe = h->queue_head))
601 return 0; /* no entry in queue */
605 LOG (GNUNET_ERROR_TYPE_DEBUG, "Failed to transmit request to DATASTORE.\n");
607 GNUNET_STATISTICS_update (h->stats,
608 gettext_noop ("# transmission request failures"),
613 if (size < (msize = qe->message_size))
619 LOG (GNUNET_ERROR_TYPE_DEBUG, "Transmitting %u byte request to DATASTORE\n",
622 memcpy (buf, &qe[1], msize);
623 qe->was_transmitted = GNUNET_YES;
624 GNUNET_SCHEDULER_cancel (qe->task);
625 qe->task = GNUNET_SCHEDULER_NO_TASK;
626 GNUNET_assert (GNUNET_NO == h->in_receive);
627 h->in_receive = GNUNET_YES;
628 GNUNET_CLIENT_receive (h->client, &receive_cb, h,
629 GNUNET_TIME_absolute_get_remaining (qe->timeout));
630 GNUNET_STATISTICS_update (h->stats,
631 gettext_noop ("# bytes sent to datastore"), 1,
638 * Process entries in the queue (or do nothing if we are already
641 * @param h handle to the datastore
644 process_queue (struct GNUNET_DATASTORE_Handle *h)
646 struct GNUNET_DATASTORE_QueueEntry *qe;
648 if (NULL == (qe = h->queue_head))
650 #if DEBUG_DATASTORE > 1
651 LOG (GNUNET_ERROR_TYPE_DEBUG, "Queue empty\n");
653 return; /* no entry in queue */
655 if (qe->was_transmitted == GNUNET_YES)
657 #if DEBUG_DATASTORE > 1
658 LOG (GNUNET_ERROR_TYPE_DEBUG, "Head request already transmitted\n");
660 return; /* waiting for replies */
664 #if DEBUG_DATASTORE > 1
665 LOG (GNUNET_ERROR_TYPE_DEBUG, "Pending transmission request\n");
667 return; /* request pending */
669 if (h->client == NULL)
671 #if DEBUG_DATASTORE > 1
672 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 */
682 LOG (GNUNET_ERROR_TYPE_DEBUG, "Queueing %u byte request to DATASTORE\n",
686 GNUNET_CLIENT_notify_transmit_ready (h->client, qe->message_size,
687 GNUNET_TIME_absolute_get_remaining
688 (qe->timeout), GNUNET_YES,
689 &transmit_request, h);
690 GNUNET_assert (GNUNET_NO == h->in_receive);
691 GNUNET_break (NULL != h->th);
696 * Dummy continuation used to do nothing (but be non-zero).
699 * @param result result
700 * @param min_expiration expiration time
701 * @param emsg error message
704 drop_status_cont (void *cls, int32_t result,
705 struct GNUNET_TIME_Absolute min_expiration,
713 * Free a queue entry. Removes the given entry from the
714 * queue and releases associated resources. Does NOT
717 * @param qe entry to free.
720 free_queue_entry (struct GNUNET_DATASTORE_QueueEntry *qe)
722 struct GNUNET_DATASTORE_Handle *h = qe->h;
724 GNUNET_CONTAINER_DLL_remove (h->queue_head, h->queue_tail, qe);
725 if (qe->task != GNUNET_SCHEDULER_NO_TASK)
727 GNUNET_SCHEDULER_cancel (qe->task);
728 qe->task = GNUNET_SCHEDULER_NO_TASK;
731 qe->was_transmitted = GNUNET_SYSERR; /* use-after-free warning */
737 * Type of a function to call when we receive a message
741 * @param msg message received, NULL on timeout or fatal error
744 process_status_message (void *cls, const struct GNUNET_MessageHeader *msg)
746 struct GNUNET_DATASTORE_Handle *h = cls;
747 struct GNUNET_DATASTORE_QueueEntry *qe;
748 struct StatusContext rc;
749 const struct StatusMessage *sm;
754 if (NULL == (qe = h->queue_head))
763 was_transmitted = qe->was_transmitted;
764 free_queue_entry (qe);
765 if (was_transmitted == GNUNET_YES)
770 rc.cont (rc.cont_cls, GNUNET_SYSERR,
771 GNUNET_TIME_UNIT_ZERO_ABS,
772 _("Failed to receive status response from database."));
775 GNUNET_assert (GNUNET_YES == qe->was_transmitted);
776 free_queue_entry (qe);
777 if ((ntohs (msg->size) < sizeof (struct StatusMessage)) ||
778 (ntohs (msg->type) != GNUNET_MESSAGE_TYPE_DATASTORE_STATUS))
781 h->retry_time = GNUNET_TIME_UNIT_ZERO;
784 rc.cont (rc.cont_cls, GNUNET_SYSERR,
785 GNUNET_TIME_UNIT_ZERO_ABS,
786 _("Error reading response from datastore service"));
789 sm = (const struct StatusMessage *) msg;
790 status = ntohl (sm->status);
792 if (ntohs (msg->size) > sizeof (struct StatusMessage))
794 emsg = (const char *) &sm[1];
795 if (emsg[ntohs (msg->size) - sizeof (struct StatusMessage) - 1] != '\0')
798 emsg = _("Invalid error message received from datastore service");
801 if ((status == GNUNET_SYSERR) && (emsg == NULL))
804 emsg = _("Invalid error message received from datastore service");
807 LOG (GNUNET_ERROR_TYPE_DEBUG, "Received status %d/%s\n", (int) status, emsg);
809 GNUNET_STATISTICS_update (h->stats,
810 gettext_noop ("# status messages received"), 1,
812 h->retry_time.rel_value = 0;
815 rc.cont (rc.cont_cls, status,
816 GNUNET_TIME_absolute_ntoh (sm->min_expiration),
822 * Store an item in the datastore. If the item is already present,
823 * the priorities are summed up and the higher expiration time and
824 * lower anonymity level is used.
826 * @param h handle to the datastore
827 * @param rid reservation ID to use (from "reserve"); use 0 if no
828 * prior reservation was made
829 * @param key key for the value
830 * @param size number of bytes in data
831 * @param data content stored
832 * @param type type of the content
833 * @param priority priority of the content
834 * @param anonymity anonymity-level for the content
835 * @param replication how often should the content be replicated to other peers?
836 * @param expiration expiration time for the content
837 * @param queue_priority ranking of this request in the priority queue
838 * @param max_queue_size at what queue size should this request be dropped
839 * (if other requests of higher priority are in the queue)
840 * @param timeout timeout for the operation
841 * @param cont continuation to call when done
842 * @param cont_cls closure for cont
843 * @return NULL if the entry was not queued, otherwise a handle that can be used to
844 * cancel; note that even if NULL is returned, the callback will be invoked
845 * (or rather, will already have been invoked)
847 struct GNUNET_DATASTORE_QueueEntry *
848 GNUNET_DATASTORE_put (struct GNUNET_DATASTORE_Handle *h, uint32_t rid,
849 const GNUNET_HashCode * key, size_t size,
850 const void *data, enum GNUNET_BLOCK_Type type,
851 uint32_t priority, uint32_t anonymity,
852 uint32_t replication,
853 struct GNUNET_TIME_Absolute expiration,
854 unsigned int queue_priority, unsigned int max_queue_size,
855 struct GNUNET_TIME_Relative timeout,
856 GNUNET_DATASTORE_ContinuationWithStatus cont,
859 struct GNUNET_DATASTORE_QueueEntry *qe;
860 struct DataMessage *dm;
862 union QueueContext qc;
865 LOG (GNUNET_ERROR_TYPE_DEBUG,
866 "Asked to put %u bytes of data under key `%s' for %llu ms\n", size,
868 GNUNET_TIME_absolute_get_remaining (expiration).rel_value);
870 msize = sizeof (struct DataMessage) + size;
871 GNUNET_assert (msize < GNUNET_SERVER_MAX_MESSAGE_SIZE);
873 qc.sc.cont_cls = cont_cls;
874 qe = make_queue_entry (h, msize, queue_priority, max_queue_size, timeout,
875 &process_status_message, &qc);
879 LOG (GNUNET_ERROR_TYPE_DEBUG, "Could not create queue entry for PUT\n");
883 GNUNET_STATISTICS_update (h->stats, gettext_noop ("# PUT requests executed"),
885 dm = (struct DataMessage *) &qe[1];
886 dm->header.type = htons (GNUNET_MESSAGE_TYPE_DATASTORE_PUT);
887 dm->header.size = htons (msize);
888 dm->rid = htonl (rid);
889 dm->size = htonl ((uint32_t) size);
890 dm->type = htonl (type);
891 dm->priority = htonl (priority);
892 dm->anonymity = htonl (anonymity);
893 dm->replication = htonl (replication);
894 dm->reserved = htonl (0);
895 dm->uid = GNUNET_htonll (0);
896 dm->expiration = GNUNET_TIME_absolute_hton (expiration);
898 memcpy (&dm[1], data, size);
905 * Reserve space in the datastore. This function should be used
906 * to avoid "out of space" failures during a longer sequence of "put"
907 * operations (for example, when a file is being inserted).
909 * @param h handle to the datastore
910 * @param amount how much space (in bytes) should be reserved (for content only)
911 * @param entries how many entries will be created (to calculate per-entry overhead)
912 * @param queue_priority ranking of this request in the priority queue
913 * @param max_queue_size at what queue size should this request be dropped
914 * (if other requests of higher priority are in the queue)
915 * @param timeout how long to wait at most for a response (or before dying in queue)
916 * @param cont continuation to call when done; "success" will be set to
917 * a positive reservation value if space could be reserved.
918 * @param cont_cls closure for cont
919 * @return NULL if the entry was not queued, otherwise a handle that can be used to
920 * cancel; note that even if NULL is returned, the callback will be invoked
921 * (or rather, will already have been invoked)
923 struct GNUNET_DATASTORE_QueueEntry *
924 GNUNET_DATASTORE_reserve (struct GNUNET_DATASTORE_Handle *h, uint64_t amount,
925 uint32_t entries, unsigned int queue_priority,
926 unsigned int max_queue_size,
927 struct GNUNET_TIME_Relative timeout,
928 GNUNET_DATASTORE_ContinuationWithStatus cont,
931 struct GNUNET_DATASTORE_QueueEntry *qe;
932 struct ReserveMessage *rm;
933 union QueueContext qc;
936 cont = &drop_status_cont;
938 LOG (GNUNET_ERROR_TYPE_DEBUG,
939 "Asked to reserve %llu bytes of data and %u entries\n",
940 (unsigned long long) amount, (unsigned int) entries);
943 qc.sc.cont_cls = cont_cls;
944 qe = make_queue_entry (h, sizeof (struct ReserveMessage), queue_priority,
945 max_queue_size, timeout, &process_status_message, &qc);
949 LOG (GNUNET_ERROR_TYPE_DEBUG, "Could not create queue entry to reserve\n");
953 GNUNET_STATISTICS_update (h->stats,
954 gettext_noop ("# RESERVE requests executed"), 1,
956 rm = (struct ReserveMessage *) &qe[1];
957 rm->header.type = htons (GNUNET_MESSAGE_TYPE_DATASTORE_RESERVE);
958 rm->header.size = htons (sizeof (struct ReserveMessage));
959 rm->entries = htonl (entries);
960 rm->amount = GNUNET_htonll (amount);
967 * Signal that all of the data for which a reservation was made has
968 * been stored and that whatever excess space might have been reserved
969 * can now be released.
971 * @param h handle to the datastore
972 * @param rid reservation ID (value of "success" in original continuation
973 * from the "reserve" function).
974 * @param queue_priority ranking of this request in the priority queue
975 * @param max_queue_size at what queue size should this request be dropped
976 * (if other requests of higher priority are in the queue)
977 * @param queue_priority ranking of this request in the priority queue
978 * @param max_queue_size at what queue size should this request be dropped
979 * (if other requests of higher priority are in the queue)
980 * @param timeout how long to wait at most for a response
981 * @param cont continuation to call when done
982 * @param cont_cls closure for cont
983 * @return NULL if the entry was not queued, otherwise a handle that can be used to
984 * cancel; note that even if NULL is returned, the callback will be invoked
985 * (or rather, will already have been invoked)
987 struct GNUNET_DATASTORE_QueueEntry *
988 GNUNET_DATASTORE_release_reserve (struct GNUNET_DATASTORE_Handle *h,
989 uint32_t rid, unsigned int queue_priority,
990 unsigned int max_queue_size,
991 struct GNUNET_TIME_Relative timeout,
992 GNUNET_DATASTORE_ContinuationWithStatus cont,
995 struct GNUNET_DATASTORE_QueueEntry *qe;
996 struct ReleaseReserveMessage *rrm;
997 union QueueContext qc;
1000 cont = &drop_status_cont;
1002 LOG (GNUNET_ERROR_TYPE_DEBUG, "Asked to release reserve %d\n", rid);
1005 qc.sc.cont_cls = cont_cls;
1006 qe = make_queue_entry (h, sizeof (struct ReleaseReserveMessage),
1007 queue_priority, max_queue_size, timeout,
1008 &process_status_message, &qc);
1012 LOG (GNUNET_ERROR_TYPE_DEBUG,
1013 "Could not create queue entry to release reserve\n");
1017 GNUNET_STATISTICS_update (h->stats,
1019 ("# RELEASE RESERVE requests executed"), 1,
1021 rrm = (struct ReleaseReserveMessage *) &qe[1];
1022 rrm->header.type = htons (GNUNET_MESSAGE_TYPE_DATASTORE_RELEASE_RESERVE);
1023 rrm->header.size = htons (sizeof (struct ReleaseReserveMessage));
1024 rrm->rid = htonl (rid);
1031 * Update a value in the datastore.
1033 * @param h handle to the datastore
1034 * @param uid identifier for the value
1035 * @param priority how much to increase the priority of the value
1036 * @param expiration new expiration value should be MAX of existing and this argument
1037 * @param queue_priority ranking of this request in the priority queue
1038 * @param max_queue_size at what queue size should this request be dropped
1039 * (if other requests of higher priority are in the queue)
1040 * @param timeout how long to wait at most for a response
1041 * @param cont continuation to call when done
1042 * @param cont_cls closure for cont
1043 * @return NULL if the entry was not queued, otherwise a handle that can be used to
1044 * cancel; note that even if NULL is returned, the callback will be invoked
1045 * (or rather, will already have been invoked)
1047 struct GNUNET_DATASTORE_QueueEntry *
1048 GNUNET_DATASTORE_update (struct GNUNET_DATASTORE_Handle *h, uint64_t uid,
1050 struct GNUNET_TIME_Absolute expiration,
1051 unsigned int queue_priority,
1052 unsigned int max_queue_size,
1053 struct GNUNET_TIME_Relative timeout,
1054 GNUNET_DATASTORE_ContinuationWithStatus cont,
1057 struct GNUNET_DATASTORE_QueueEntry *qe;
1058 struct UpdateMessage *um;
1059 union QueueContext qc;
1062 cont = &drop_status_cont;
1064 LOG (GNUNET_ERROR_TYPE_DEBUG,
1065 "Asked to update entry %llu raising priority by %u and expiration to %llu\n",
1066 uid, (unsigned int) priority, (unsigned long long) expiration.abs_value);
1069 qc.sc.cont_cls = cont_cls;
1070 qe = make_queue_entry (h, sizeof (struct UpdateMessage), queue_priority,
1071 max_queue_size, timeout, &process_status_message, &qc);
1075 LOG (GNUNET_ERROR_TYPE_DEBUG, "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 "cont"inuation 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 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 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;
1131 LOG (GNUNET_ERROR_TYPE_DEBUG, "Asked to remove %u bytes under key `%s'\n",
1132 size, GNUNET_h2s (key));
1135 qc.sc.cont_cls = cont_cls;
1136 msize = sizeof (struct DataMessage) + size;
1137 GNUNET_assert (msize < GNUNET_SERVER_MAX_MESSAGE_SIZE);
1138 qe = make_queue_entry (h, msize, queue_priority, max_queue_size, timeout,
1139 &process_status_message, &qc);
1143 LOG (GNUNET_ERROR_TYPE_DEBUG, "Could not create queue entry for REMOVE\n");
1147 GNUNET_STATISTICS_update (h->stats,
1148 gettext_noop ("# REMOVE requests executed"), 1,
1150 dm = (struct DataMessage *) &qe[1];
1151 dm->header.type = htons (GNUNET_MESSAGE_TYPE_DATASTORE_REMOVE);
1152 dm->header.size = htons (msize);
1153 dm->rid = htonl (0);
1154 dm->size = htonl (size);
1155 dm->type = htonl (0);
1156 dm->priority = htonl (0);
1157 dm->anonymity = htonl (0);
1158 dm->uid = GNUNET_htonll (0);
1159 dm->expiration = GNUNET_TIME_absolute_hton (GNUNET_TIME_UNIT_ZERO_ABS);
1161 memcpy (&dm[1], data, size);
1168 * Type of a function to call when we receive a message
1171 * @param cls closure
1172 * @param msg message received, NULL on timeout or fatal error
1175 process_result_message (void *cls, const struct GNUNET_MessageHeader *msg)
1177 struct GNUNET_DATASTORE_Handle *h = cls;
1178 struct GNUNET_DATASTORE_QueueEntry *qe;
1179 struct ResultContext rc;
1180 const struct DataMessage *dm;
1181 int was_transmitted;
1186 GNUNET_assert (NULL != qe);
1188 was_transmitted = qe->was_transmitted;
1189 free_queue_entry (qe);
1190 if (was_transmitted == GNUNET_YES)
1192 LOG (GNUNET_ERROR_TYPE_WARNING,
1193 _("Failed to receive response from database.\n"));
1200 if (rc.proc != NULL)
1201 rc.proc (rc.proc_cls, NULL, 0, NULL, 0, 0, 0, GNUNET_TIME_UNIT_ZERO_ABS,
1205 if (ntohs (msg->type) == GNUNET_MESSAGE_TYPE_DATASTORE_DATA_END)
1207 GNUNET_break (ntohs (msg->size) == sizeof (struct GNUNET_MessageHeader));
1210 GNUNET_assert (GNUNET_YES == qe->was_transmitted);
1211 free_queue_entry (qe);
1213 LOG (GNUNET_ERROR_TYPE_DEBUG,
1214 "Received end of result set, new queue size is %u\n", h->queue_size);
1216 h->retry_time.rel_value = 0;
1217 h->result_count = 0;
1219 if (rc.proc != NULL)
1220 rc.proc (rc.proc_cls, NULL, 0, NULL, 0, 0, 0, GNUNET_TIME_UNIT_ZERO_ABS,
1225 GNUNET_assert (NULL != qe);
1227 if (GNUNET_YES != qe->was_transmitted)
1230 free_queue_entry (qe);
1231 h->retry_time = GNUNET_TIME_UNIT_ZERO;
1233 if (rc.proc != NULL)
1234 rc.proc (rc.proc_cls, NULL, 0, NULL, 0, 0, 0, GNUNET_TIME_UNIT_ZERO_ABS,
1238 if ((ntohs (msg->size) < sizeof (struct DataMessage)) ||
1239 (ntohs (msg->type) != GNUNET_MESSAGE_TYPE_DATASTORE_DATA) ||
1240 (ntohs (msg->size) !=
1241 sizeof (struct DataMessage) +
1242 ntohl (((const struct DataMessage *) msg)->size)))
1245 free_queue_entry (qe);
1246 h->retry_time = GNUNET_TIME_UNIT_ZERO;
1248 if (rc.proc != NULL)
1249 rc.proc (rc.proc_cls, NULL, 0, NULL, 0, 0, 0, GNUNET_TIME_UNIT_ZERO_ABS,
1253 GNUNET_STATISTICS_update (h->stats, gettext_noop ("# Results received"), 1,
1255 dm = (const struct DataMessage *) msg;
1257 LOG (GNUNET_ERROR_TYPE_DEBUG,
1258 "Received result %llu with type %u and size %u with key %s\n",
1259 (unsigned long long) GNUNET_ntohll (dm->uid), ntohl (dm->type),
1260 ntohl (dm->size), GNUNET_h2s (&dm->key));
1262 free_queue_entry (qe);
1263 h->retry_time.rel_value = 0;
1265 if (rc.proc != NULL)
1266 rc.proc (rc.proc_cls, &dm->key, ntohl (dm->size), &dm[1], ntohl (dm->type),
1267 ntohl (dm->priority), ntohl (dm->anonymity),
1268 GNUNET_TIME_absolute_ntoh (dm->expiration),
1269 GNUNET_ntohll (dm->uid));
1274 * Get a random value from the datastore for content replication.
1275 * Returns a single, random value among those with the highest
1276 * replication score, lowering positive replication scores by one for
1277 * the chosen value (if only content with a replication score exists,
1278 * a random value is returned and replication scores are not changed).
1280 * @param h handle to the datastore
1281 * @param queue_priority ranking of this request in the priority queue
1282 * @param max_queue_size at what queue size should this request be dropped
1283 * (if other requests of higher priority are in the queue)
1284 * @param timeout how long to wait at most for a response
1285 * @param proc function to call on a random value; it
1286 * will be called once with a value (if available)
1287 * and always once with a value of NULL.
1288 * @param proc_cls closure for proc
1289 * @return NULL if the entry was not queued, otherwise a handle that can be used to
1292 struct GNUNET_DATASTORE_QueueEntry *
1293 GNUNET_DATASTORE_get_for_replication (struct GNUNET_DATASTORE_Handle *h,
1294 unsigned int queue_priority,
1295 unsigned int max_queue_size,
1296 struct GNUNET_TIME_Relative timeout,
1297 GNUNET_DATASTORE_DatumProcessor proc,
1300 struct GNUNET_DATASTORE_QueueEntry *qe;
1301 struct GNUNET_MessageHeader *m;
1302 union QueueContext qc;
1304 GNUNET_assert (NULL != proc);
1306 LOG (GNUNET_ERROR_TYPE_DEBUG, "Asked to get replication entry in %llu ms\n",
1307 (unsigned long long) timeout.rel_value);
1310 qc.rc.proc_cls = proc_cls;
1311 qe = make_queue_entry (h, sizeof (struct GNUNET_MessageHeader),
1312 queue_priority, max_queue_size, timeout,
1313 &process_result_message, &qc);
1317 LOG (GNUNET_ERROR_TYPE_DEBUG,
1318 "Could not create queue entry for GET REPLICATION\n");
1322 GNUNET_STATISTICS_update (h->stats,
1324 ("# GET REPLICATION requests executed"), 1,
1326 m = (struct GNUNET_MessageHeader *) &qe[1];
1327 m->type = htons (GNUNET_MESSAGE_TYPE_DATASTORE_GET_REPLICATION);
1328 m->size = htons (sizeof (struct GNUNET_MessageHeader));
1335 * Get a single zero-anonymity value from the datastore.
1337 * @param h handle to the datastore
1338 * @param offset offset of the result (modulo num-results); set to
1339 * a random 64-bit value initially; then increment by
1340 * one each time; detect that all results have been found by uid
1341 * being again the first uid ever returned.
1342 * @param queue_priority ranking of this request in the priority queue
1343 * @param max_queue_size at what queue size should this request be dropped
1344 * (if other requests of higher priority are in the queue)
1345 * @param timeout how long to wait at most for a response
1346 * @param type allowed type for the operation (never zero)
1347 * @param proc function to call on a random value; it
1348 * will be called once with a value (if available)
1349 * or with NULL if none value exists.
1350 * @param proc_cls closure for proc
1351 * @return NULL if the entry was not queued, otherwise a handle that can be used to
1354 struct GNUNET_DATASTORE_QueueEntry *
1355 GNUNET_DATASTORE_get_zero_anonymity (struct GNUNET_DATASTORE_Handle *h,
1357 unsigned int queue_priority,
1358 unsigned int max_queue_size,
1359 struct GNUNET_TIME_Relative timeout,
1360 enum GNUNET_BLOCK_Type type,
1361 GNUNET_DATASTORE_DatumProcessor proc,
1364 struct GNUNET_DATASTORE_QueueEntry *qe;
1365 struct GetZeroAnonymityMessage *m;
1366 union QueueContext qc;
1368 GNUNET_assert (NULL != proc);
1369 GNUNET_assert (type != GNUNET_BLOCK_TYPE_ANY);
1371 LOG (GNUNET_ERROR_TYPE_DEBUG,
1372 "Asked to get %llu-th zero-anonymity entry of type %d in %llu ms\n",
1373 (unsigned long long) offset, type,
1374 (unsigned long long) timeout.rel_value);
1377 qc.rc.proc_cls = proc_cls;
1378 qe = make_queue_entry (h, sizeof (struct GetZeroAnonymityMessage),
1379 queue_priority, max_queue_size, timeout,
1380 &process_result_message, &qc);
1384 LOG (GNUNET_ERROR_TYPE_DEBUG,
1385 "Could not create queue entry for zero-anonymity procation\n");
1389 GNUNET_STATISTICS_update (h->stats,
1391 ("# GET ZERO ANONYMITY requests executed"), 1,
1393 m = (struct GetZeroAnonymityMessage *) &qe[1];
1394 m->header.type = htons (GNUNET_MESSAGE_TYPE_DATASTORE_GET_ZERO_ANONYMITY);
1395 m->header.size = htons (sizeof (struct GetZeroAnonymityMessage));
1396 m->type = htonl ((uint32_t) type);
1397 m->offset = GNUNET_htonll (offset);
1404 * Get a result for a particular key from the datastore. The processor
1405 * will only be called once.
1407 * @param h handle to the datastore
1408 * @param offset offset of the result (modulo num-results); set to
1409 * a random 64-bit value initially; then increment by
1410 * one each time; detect that all results have been found by uid
1411 * being again the first uid ever returned.
1412 * @param key maybe NULL (to match all entries)
1413 * @param type desired type, 0 for any
1414 * @param queue_priority ranking of this request in the priority queue
1415 * @param max_queue_size at what queue size should this request be dropped
1416 * (if other requests of higher priority are in the queue)
1417 * @param timeout how long to wait at most for a response
1418 * @param proc function to call on each matching value;
1419 * will be called once with a NULL value at the end
1420 * @param proc_cls closure for proc
1421 * @return NULL if the entry was not queued, otherwise a handle that can be used to
1424 struct GNUNET_DATASTORE_QueueEntry *
1425 GNUNET_DATASTORE_get_key (struct GNUNET_DATASTORE_Handle *h, uint64_t offset,
1426 const GNUNET_HashCode * key,
1427 enum GNUNET_BLOCK_Type type,
1428 unsigned int queue_priority,
1429 unsigned int max_queue_size,
1430 struct GNUNET_TIME_Relative timeout,
1431 GNUNET_DATASTORE_DatumProcessor proc, void *proc_cls)
1433 struct GNUNET_DATASTORE_QueueEntry *qe;
1434 struct GetMessage *gm;
1435 union QueueContext qc;
1437 GNUNET_assert (NULL != proc);
1439 LOG (GNUNET_ERROR_TYPE_DEBUG,
1440 "Asked to look for data of type %u under key `%s'\n",
1441 (unsigned int) type, GNUNET_h2s (key));
1444 qc.rc.proc_cls = proc_cls;
1445 qe = make_queue_entry (h, sizeof (struct GetMessage), queue_priority,
1446 max_queue_size, timeout, &process_result_message, &qc);
1450 LOG (GNUNET_ERROR_TYPE_DEBUG, "Could not queue request for `%s'\n",
1455 GNUNET_STATISTICS_update (h->stats, gettext_noop ("# GET requests executed"),
1457 gm = (struct GetMessage *) &qe[1];
1458 gm->header.type = htons (GNUNET_MESSAGE_TYPE_DATASTORE_GET);
1459 gm->type = htonl (type);
1460 gm->offset = GNUNET_htonll (offset);
1463 gm->header.size = htons (sizeof (struct GetMessage));
1469 htons (sizeof (struct GetMessage) - sizeof (GNUNET_HashCode));
1477 * Cancel a datastore operation. The final callback from the
1478 * operation must not have been done yet.
1480 * @param qe operation to cancel
1483 GNUNET_DATASTORE_cancel (struct GNUNET_DATASTORE_QueueEntry *qe)
1485 struct GNUNET_DATASTORE_Handle *h;
1487 GNUNET_assert (GNUNET_SYSERR != qe->was_transmitted);
1490 LOG (GNUNET_ERROR_TYPE_DEBUG,
1491 "Pending DATASTORE request %p cancelled (%d, %d)\n", qe,
1492 qe->was_transmitted, h->queue_head == qe);
1494 if (GNUNET_YES == qe->was_transmitted)
1496 free_queue_entry (qe);
1497 h->skip_next_messages++;
1500 free_queue_entry (qe);
1505 /* end of datastore_api.c */