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"
35 * If a client stopped asking for more results, how many more do
36 * we receive from the DB before killing the connection? Trade-off
37 * between re-doing TCP handshakes and (needlessly) receiving
40 #define MAX_EXCESS_RESULTS 8
43 * Context for processing status messages.
48 * Continuation to call with the status.
50 GNUNET_DATASTORE_ContinuationWithStatus cont;
61 * Context for processing result messages.
66 * Function to call with the result.
68 GNUNET_DATASTORE_DatumProcessor proc;
79 * Context for a queue operation.
84 struct StatusContext sc;
86 struct ResultContext rc;
93 * Entry in our priority queue.
95 struct GNUNET_DATASTORE_QueueEntry
99 * This is a linked list.
101 struct GNUNET_DATASTORE_QueueEntry *next;
104 * This is a linked list.
106 struct GNUNET_DATASTORE_QueueEntry *prev;
109 * Handle to the master context.
111 struct GNUNET_DATASTORE_Handle *h;
114 * Response processor (NULL if we are not waiting for a response).
115 * This struct should be used for the closure, function-specific
116 * arguments can be passed via 'qc'.
118 GNUNET_CLIENT_MessageHandler response_proc;
121 * Function to call after transmission of the request.
123 GNUNET_DATASTORE_ContinuationWithStatus cont;
126 * Closure for 'cont'.
131 * Context for the operation.
133 union QueueContext qc;
136 * Task for timeout signalling.
138 GNUNET_SCHEDULER_TaskIdentifier task;
141 * Timeout for the current operation.
143 struct GNUNET_TIME_Absolute timeout;
146 * Priority in the queue.
148 unsigned int priority;
151 * Maximum allowed length of queue (otherwise
152 * this request should be discarded).
154 unsigned int max_queue;
157 * Number of bytes in the request message following
158 * this struct. 32-bit value for nicer memory
159 * access (and overall struct alignment).
161 uint32_t message_size;
164 * Has this message been transmitted to the service?
165 * Only ever GNUNET_YES for the head of the queue.
166 * Note that the overall struct should end at a
167 * multiple of 64 bits.
174 * Handle to the datastore service.
176 struct GNUNET_DATASTORE_Handle
182 const struct GNUNET_CONFIGURATION_Handle *cfg;
185 * Current connection to the datastore service.
187 struct GNUNET_CLIENT_Connection *client;
190 * Handle for statistics.
192 struct GNUNET_STATISTICS_Handle *stats;
195 * Current transmit handle.
197 struct GNUNET_CLIENT_TransmitHandle *th;
200 * Current head of priority queue.
202 struct GNUNET_DATASTORE_QueueEntry *queue_head;
205 * Current tail of priority queue.
207 struct GNUNET_DATASTORE_QueueEntry *queue_tail;
210 * Task for trying to reconnect.
212 GNUNET_SCHEDULER_TaskIdentifier reconnect_task;
215 * How quickly should we retry? Used for exponential back-off on
218 struct GNUNET_TIME_Relative retry_time;
221 * Number of entries in the queue.
223 unsigned int queue_size;
226 * Number of results we're receiving for the current query
227 * after application stopped to care. Used to determine when
228 * to reset the connection.
230 unsigned int result_count;
233 * Are we currently trying to receive from the service?
238 * We should ignore the next message(s) from the service.
240 unsigned int skip_next_messages;
247 * Connect to the datastore service.
249 * @param cfg configuration to use
250 * @return handle to use to access the service
252 struct GNUNET_DATASTORE_Handle *
253 GNUNET_DATASTORE_connect (const struct
254 GNUNET_CONFIGURATION_Handle
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",
274 * Transmit DROP message to datastore service.
276 * @param cls the 'struct GNUNET_DATASTORE_Handle'
277 * @param size number of bytes that can be copied to buf
278 * @param buf where to copy the drop message
279 * @return number of bytes written to buf
282 transmit_drop (void *cls,
286 struct GNUNET_DATASTORE_Handle *h = cls;
287 struct GNUNET_MessageHeader *hdr;
291 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
292 _("Failed to transmit request to drop database.\n"));
293 GNUNET_DATASTORE_disconnect (h, GNUNET_NO);
296 GNUNET_assert (size >= sizeof(struct GNUNET_MessageHeader));
298 hdr->size = htons(sizeof(struct GNUNET_MessageHeader));
299 hdr->type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_DROP);
300 GNUNET_DATASTORE_disconnect (h, GNUNET_NO);
301 return sizeof(struct GNUNET_MessageHeader);
306 * Disconnect from the datastore service (and free
307 * associated resources).
309 * @param h handle to the datastore
310 * @param drop set to GNUNET_YES to delete all data in datastore (!)
313 GNUNET_DATASTORE_disconnect (struct GNUNET_DATASTORE_Handle *h,
316 struct GNUNET_DATASTORE_QueueEntry *qe;
318 if (h->client != NULL)
320 GNUNET_CLIENT_disconnect (h->client, GNUNET_NO);
323 if (h->reconnect_task != GNUNET_SCHEDULER_NO_TASK)
325 GNUNET_SCHEDULER_cancel (h->reconnect_task);
326 h->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
330 GNUNET_CLIENT_notify_transmit_ready_cancel (h->th);
333 while (NULL != (qe = h->queue_head))
335 GNUNET_assert (NULL != qe->response_proc);
336 qe->response_proc (h, NULL);
338 if (GNUNET_YES == drop)
340 h->client = GNUNET_CLIENT_connect ("datastore", h->cfg);
341 if (h->client != NULL)
344 GNUNET_CLIENT_notify_transmit_ready (h->client,
345 sizeof(struct GNUNET_MessageHeader),
346 GNUNET_TIME_UNIT_MINUTES,
351 GNUNET_CLIENT_disconnect (h->client, GNUNET_NO);
356 GNUNET_STATISTICS_destroy (h->stats,
364 * A request has timed out (before being transmitted to the service).
366 * @param cls the 'struct GNUNET_DATASTORE_QueueEntry'
367 * @param tc scheduler context
370 timeout_queue_entry (void *cls,
371 const struct GNUNET_SCHEDULER_TaskContext *tc)
373 struct GNUNET_DATASTORE_QueueEntry *qe = cls;
375 GNUNET_STATISTICS_update (qe->h->stats,
376 gettext_noop ("# queue entry timeouts"),
379 qe->task = GNUNET_SCHEDULER_NO_TASK;
380 GNUNET_assert (qe->was_transmitted == GNUNET_NO);
381 qe->response_proc (qe->h, NULL);
386 * Create a new entry for our priority queue (and possibly discard other entires if
387 * the queue is getting too long).
389 * @param h handle to the datastore
390 * @param msize size of the message to queue
391 * @param queue_priority priority of the entry
392 * @param max_queue_size at what queue size should this request be dropped
393 * (if other requests of higher priority are in the queue)
394 * @param timeout timeout for the operation
395 * @param response_proc function to call with replies (can be NULL)
396 * @param qc client context (NOT a closure for response_proc)
397 * @return NULL if the queue is full
399 static struct GNUNET_DATASTORE_QueueEntry *
400 make_queue_entry (struct GNUNET_DATASTORE_Handle *h,
402 unsigned int queue_priority,
403 unsigned int max_queue_size,
404 struct GNUNET_TIME_Relative timeout,
405 GNUNET_CLIENT_MessageHandler response_proc,
406 const union QueueContext *qc)
408 struct GNUNET_DATASTORE_QueueEntry *ret;
409 struct GNUNET_DATASTORE_QueueEntry *pos;
414 while ( (pos != NULL) &&
415 (c < max_queue_size) &&
416 (pos->priority >= queue_priority) )
421 if (c >= max_queue_size)
423 GNUNET_STATISTICS_update (h->stats,
424 gettext_noop ("# queue overflows"),
429 ret = GNUNET_malloc (sizeof (struct GNUNET_DATASTORE_QueueEntry) + msize);
431 ret->response_proc = response_proc;
433 ret->timeout = GNUNET_TIME_relative_to_absolute (timeout);
434 ret->priority = queue_priority;
435 ret->max_queue = max_queue_size;
436 ret->message_size = msize;
437 ret->was_transmitted = GNUNET_NO;
440 /* append at the tail */
446 /* do not insert at HEAD if HEAD query was already
447 transmitted and we are still receiving replies! */
448 if ( (pos == NULL) &&
449 (h->queue_head->was_transmitted) )
453 GNUNET_STATISTICS_update (h->stats,
454 gettext_noop ("# queue entries created"),
457 GNUNET_CONTAINER_DLL_insert_after (h->queue_head,
462 ret->task = GNUNET_SCHEDULER_add_delayed (timeout,
463 &timeout_queue_entry,
468 if ( (pos->max_queue < h->queue_size) &&
469 (pos->was_transmitted == GNUNET_NO) )
471 GNUNET_assert (pos->response_proc != NULL);
472 /* move 'pos' element to head so that it will be
473 killed on 'NULL' call below */
474 GNUNET_CONTAINER_DLL_remove (h->queue_head,
477 GNUNET_CONTAINER_DLL_insert (h->queue_head,
480 GNUNET_STATISTICS_update (h->stats,
481 gettext_noop ("# Requests dropped from datastore queue"),
484 pos->response_proc (h, NULL);
494 * Process entries in the queue (or do nothing if we are already
497 * @param h handle to the datastore
500 process_queue (struct GNUNET_DATASTORE_Handle *h);
504 * Try reconnecting to the datastore service.
506 * @param cls the 'struct GNUNET_DATASTORE_Handle'
507 * @param tc scheduler context
510 try_reconnect (void *cls,
511 const struct GNUNET_SCHEDULER_TaskContext *tc)
513 struct GNUNET_DATASTORE_Handle *h = cls;
515 if (h->retry_time.rel_value < GNUNET_CONSTANTS_SERVICE_RETRY.rel_value)
516 h->retry_time = GNUNET_CONSTANTS_SERVICE_RETRY;
518 h->retry_time = GNUNET_TIME_relative_multiply (h->retry_time, 2);
519 if (h->retry_time.rel_value > GNUNET_CONSTANTS_SERVICE_TIMEOUT.rel_value)
520 h->retry_time = GNUNET_CONSTANTS_SERVICE_TIMEOUT;
521 h->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
522 h->client = GNUNET_CLIENT_connect ("datastore", h->cfg);
523 if (h->client == NULL)
525 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
526 "DATASTORE reconnect failed (fatally)\n");
529 GNUNET_STATISTICS_update (h->stats,
530 gettext_noop ("# datastore connections (re)created"),
534 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
535 "Reconnected to DATASTORE\n");
542 * Disconnect from the service and then try reconnecting to the datastore service
545 * @param h handle to datastore to disconnect and reconnect
548 do_disconnect (struct GNUNET_DATASTORE_Handle *h)
550 if (h->client == NULL)
553 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
554 "client NULL in disconnect, will not try to reconnect\n");
559 GNUNET_STATISTICS_update (stats,
560 gettext_noop ("# reconnected to DATASTORE"),
564 GNUNET_CLIENT_disconnect (h->client, GNUNET_NO);
565 h->skip_next_messages = 0;
567 h->reconnect_task = GNUNET_SCHEDULER_add_delayed (h->retry_time,
574 * Transmit request from queue to datastore service.
576 * @param cls the 'struct GNUNET_DATASTORE_Handle'
577 * @param size number of bytes that can be copied to buf
578 * @param buf where to copy the drop message
579 * @return number of bytes written to buf
582 transmit_request (void *cls,
586 struct GNUNET_DATASTORE_Handle *h = cls;
587 struct GNUNET_DATASTORE_QueueEntry *qe;
591 if (NULL == (qe = h->queue_head))
592 return 0; /* no entry in queue */
595 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
596 _("Failed to transmit request to DATASTORE.\n"));
597 GNUNET_STATISTICS_update (h->stats,
598 gettext_noop ("# transmission request failures"),
604 if (size < (msize = qe->message_size))
610 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
611 "Transmitting %u byte request to DATASTORE\n",
614 memcpy (buf, &qe[1], msize);
615 qe->was_transmitted = GNUNET_YES;
616 GNUNET_SCHEDULER_cancel (qe->task);
617 qe->task = GNUNET_SCHEDULER_NO_TASK;
618 GNUNET_assert (GNUNET_NO == h->in_receive);
619 h->in_receive = GNUNET_YES;
620 GNUNET_CLIENT_receive (h->client,
623 GNUNET_TIME_absolute_get_remaining (qe->timeout));
624 GNUNET_STATISTICS_update (h->stats,
625 gettext_noop ("# bytes sent to datastore"),
633 * Process entries in the queue (or do nothing if we are already
636 * @param h handle to the datastore
639 process_queue (struct GNUNET_DATASTORE_Handle *h)
641 struct GNUNET_DATASTORE_QueueEntry *qe;
643 if (NULL == (qe = h->queue_head))
645 #if DEBUG_DATASTORE > 1
646 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
649 return; /* no entry in queue */
651 if (qe->was_transmitted == GNUNET_YES)
653 #if DEBUG_DATASTORE > 1
654 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
655 "Head request already transmitted\n");
657 return; /* waiting for replies */
661 #if DEBUG_DATASTORE > 1
662 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
663 "Pending transmission request\n");
665 return; /* request pending */
667 if (h->client == NULL)
669 #if DEBUG_DATASTORE > 1
670 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
673 return; /* waiting for reconnect */
675 if (GNUNET_YES == h->in_receive)
677 /* wait for response to previous query */
681 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
682 "Queueing %u byte request to DATASTORE\n",
685 h->th = GNUNET_CLIENT_notify_transmit_ready (h->client,
687 GNUNET_TIME_absolute_get_remaining (qe->timeout),
691 GNUNET_assert (GNUNET_NO == h->in_receive);
692 GNUNET_break (NULL != h->th);
697 * Dummy continuation used to do nothing (but be non-zero).
700 * @param result result
701 * @param emsg error message
704 drop_status_cont (void *cls, int32_t result, const char *emsg)
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,
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,
746 GNUNET_MessageHeader * msg)
748 struct GNUNET_DATASTORE_Handle *h = cls;
749 struct GNUNET_DATASTORE_QueueEntry *qe;
750 struct StatusContext rc;
751 const struct StatusMessage *sm;
756 h->in_receive = GNUNET_NO;
757 if (h->skip_next_messages > 0)
759 h->skip_next_messages--;
763 if (NULL == (qe = h->queue_head))
772 was_transmitted = qe->was_transmitted;
773 free_queue_entry (qe);
774 if (NULL == h->client)
775 return; /* forced disconnect */
777 rc.cont (rc.cont_cls,
779 _("Failed to receive status response from database."));
780 if (was_transmitted == GNUNET_YES)
786 GNUNET_assert (GNUNET_YES == qe->was_transmitted);
787 free_queue_entry (qe);
788 if ( (ntohs(msg->size) < sizeof(struct StatusMessage)) ||
789 (ntohs(msg->type) != GNUNET_MESSAGE_TYPE_DATASTORE_STATUS) )
792 h->retry_time = GNUNET_TIME_UNIT_ZERO;
795 rc.cont (rc.cont_cls,
797 _("Error reading response from datastore service"));
800 sm = (const struct StatusMessage*) msg;
801 status = ntohl(sm->status);
803 if (ntohs(msg->size) > sizeof(struct StatusMessage))
805 emsg = (const char*) &sm[1];
806 if (emsg[ntohs(msg->size) - sizeof(struct StatusMessage) - 1] != '\0')
809 emsg = _("Invalid error message received from datastore service");
812 if ( (status == GNUNET_SYSERR) &&
816 emsg = _("Invalid error message received from datastore service");
819 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
820 "Received status %d/%s\n",
824 GNUNET_STATISTICS_update (h->stats,
825 gettext_noop ("# status messages received"),
828 h->retry_time.rel_value = 0;
831 rc.cont (rc.cont_cls,
838 * Store an item in the datastore. If the item is already present,
839 * the priorities are summed up and the higher expiration time and
840 * lower anonymity level is used.
842 * @param h handle to the datastore
843 * @param rid reservation ID to use (from "reserve"); use 0 if no
844 * prior reservation was made
845 * @param key key for the value
846 * @param size number of bytes in data
847 * @param data content stored
848 * @param type type of the content
849 * @param priority priority of the content
850 * @param anonymity anonymity-level for the content
851 * @param replication how often should the content be replicated to other peers?
852 * @param expiration expiration time for the content
853 * @param queue_priority ranking of this request in the priority queue
854 * @param max_queue_size at what queue size should this request be dropped
855 * (if other requests of higher priority are in the queue)
856 * @param timeout timeout for the operation
857 * @param cont continuation to call when done
858 * @param cont_cls closure for cont
859 * @return NULL if the entry was not queued, otherwise a handle that can be used to
860 * cancel; note that even if NULL is returned, the callback will be invoked
861 * (or rather, will already have been invoked)
863 struct GNUNET_DATASTORE_QueueEntry *
864 GNUNET_DATASTORE_put (struct GNUNET_DATASTORE_Handle *h,
866 const GNUNET_HashCode * key,
869 enum GNUNET_BLOCK_Type type,
872 uint32_t replication,
873 struct GNUNET_TIME_Absolute expiration,
874 unsigned int queue_priority,
875 unsigned int max_queue_size,
876 struct GNUNET_TIME_Relative timeout,
877 GNUNET_DATASTORE_ContinuationWithStatus cont,
880 struct GNUNET_DATASTORE_QueueEntry *qe;
881 struct DataMessage *dm;
883 union QueueContext qc;
886 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
887 "Asked to put %u bytes of data under key `%s' for %llu ms\n",
890 GNUNET_TIME_absolute_get_remaining (expiration).rel_value);
892 msize = sizeof(struct DataMessage) + size;
893 GNUNET_assert (msize < GNUNET_SERVER_MAX_MESSAGE_SIZE);
895 qc.sc.cont_cls = cont_cls;
896 qe = make_queue_entry (h, msize,
897 queue_priority, max_queue_size, timeout,
898 &process_status_message, &qc);
902 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
903 "Could not create queue entry for PUT\n");
907 GNUNET_STATISTICS_update (h->stats,
908 gettext_noop ("# PUT requests executed"),
911 dm = (struct DataMessage* ) &qe[1];
912 dm->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_PUT);
913 dm->header.size = htons(msize);
914 dm->rid = htonl(rid);
915 dm->size = htonl( (uint32_t) size);
916 dm->type = htonl(type);
917 dm->priority = htonl(priority);
918 dm->anonymity = htonl(anonymity);
919 dm->replication = htonl (replication);
920 dm->reserved = htonl (0);
921 dm->uid = GNUNET_htonll(0);
922 dm->expiration = GNUNET_TIME_absolute_hton(expiration);
924 memcpy (&dm[1], data, size);
931 * Reserve space in the datastore. This function should be used
932 * to avoid "out of space" failures during a longer sequence of "put"
933 * operations (for example, when a file is being inserted).
935 * @param h handle to the datastore
936 * @param amount how much space (in bytes) should be reserved (for content only)
937 * @param entries how many entries will be created (to calculate per-entry overhead)
938 * @param queue_priority ranking of this request in the priority queue
939 * @param max_queue_size at what queue size should this request be dropped
940 * (if other requests of higher priority are in the queue)
941 * @param timeout how long to wait at most for a response (or before dying in queue)
942 * @param cont continuation to call when done; "success" will be set to
943 * a positive reservation value if space could be reserved.
944 * @param cont_cls closure for cont
945 * @return NULL if the entry was not queued, otherwise a handle that can be used to
946 * cancel; note that even if NULL is returned, the callback will be invoked
947 * (or rather, will already have been invoked)
949 struct GNUNET_DATASTORE_QueueEntry *
950 GNUNET_DATASTORE_reserve (struct GNUNET_DATASTORE_Handle *h,
953 unsigned int queue_priority,
954 unsigned int max_queue_size,
955 struct GNUNET_TIME_Relative timeout,
956 GNUNET_DATASTORE_ContinuationWithStatus cont,
959 struct GNUNET_DATASTORE_QueueEntry *qe;
960 struct ReserveMessage *rm;
961 union QueueContext qc;
964 cont = &drop_status_cont;
966 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
967 "Asked to reserve %llu bytes of data and %u entries'\n",
968 (unsigned long long) amount,
969 (unsigned int) entries);
972 qc.sc.cont_cls = cont_cls;
973 qe = make_queue_entry (h, sizeof(struct ReserveMessage),
974 queue_priority, max_queue_size, timeout,
975 &process_status_message, &qc);
979 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
980 "Could not create queue entry to reserve\n");
984 GNUNET_STATISTICS_update (h->stats,
985 gettext_noop ("# RESERVE requests executed"),
988 rm = (struct ReserveMessage*) &qe[1];
989 rm->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_RESERVE);
990 rm->header.size = htons(sizeof (struct ReserveMessage));
991 rm->entries = htonl(entries);
992 rm->amount = GNUNET_htonll(amount);
999 * Signal that all of the data for which a reservation was made has
1000 * been stored and that whatever excess space might have been reserved
1001 * can now be released.
1003 * @param h handle to the datastore
1004 * @param rid reservation ID (value of "success" in original continuation
1005 * from the "reserve" function).
1006 * @param queue_priority ranking of this request in the priority queue
1007 * @param max_queue_size at what queue size should this request be dropped
1008 * (if other requests of higher priority are in the queue)
1009 * @param queue_priority ranking of this request in the priority queue
1010 * @param max_queue_size at what queue size should this request be dropped
1011 * (if other requests of higher priority are in the queue)
1012 * @param timeout how long to wait at most for a response
1013 * @param cont continuation to call when done
1014 * @param cont_cls closure for cont
1015 * @return NULL if the entry was not queued, otherwise a handle that can be used to
1016 * cancel; note that even if NULL is returned, the callback will be invoked
1017 * (or rather, will already have been invoked)
1019 struct GNUNET_DATASTORE_QueueEntry *
1020 GNUNET_DATASTORE_release_reserve (struct GNUNET_DATASTORE_Handle *h,
1022 unsigned int queue_priority,
1023 unsigned int max_queue_size,
1024 struct GNUNET_TIME_Relative timeout,
1025 GNUNET_DATASTORE_ContinuationWithStatus cont,
1028 struct GNUNET_DATASTORE_QueueEntry *qe;
1029 struct ReleaseReserveMessage *rrm;
1030 union QueueContext qc;
1033 cont = &drop_status_cont;
1035 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1036 "Asked to release reserve %d\n",
1040 qc.sc.cont_cls = cont_cls;
1041 qe = make_queue_entry (h, sizeof(struct ReleaseReserveMessage),
1042 queue_priority, max_queue_size, timeout,
1043 &process_status_message, &qc);
1047 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1048 "Could not create queue entry to release reserve\n");
1052 GNUNET_STATISTICS_update (h->stats,
1053 gettext_noop ("# RELEASE RESERVE requests executed"),
1056 rrm = (struct ReleaseReserveMessage*) &qe[1];
1057 rrm->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_RELEASE_RESERVE);
1058 rrm->header.size = htons(sizeof (struct ReleaseReserveMessage));
1059 rrm->rid = htonl(rid);
1066 * Update a value in the datastore.
1068 * @param h handle to the datastore
1069 * @param uid identifier for the value
1070 * @param priority how much to increase the priority of the value
1071 * @param expiration new expiration value should be MAX of existing and this argument
1072 * @param queue_priority ranking of this request in the priority queue
1073 * @param max_queue_size at what queue size should this request be dropped
1074 * (if other requests of higher priority are in the queue)
1075 * @param timeout how long to wait at most for a response
1076 * @param cont continuation to call when done
1077 * @param cont_cls closure for cont
1078 * @return NULL if the entry was not queued, otherwise a handle that can be used to
1079 * cancel; note that even if NULL is returned, the callback will be invoked
1080 * (or rather, will already have been invoked)
1082 struct GNUNET_DATASTORE_QueueEntry *
1083 GNUNET_DATASTORE_update (struct GNUNET_DATASTORE_Handle *h,
1086 struct GNUNET_TIME_Absolute expiration,
1087 unsigned int queue_priority,
1088 unsigned int max_queue_size,
1089 struct GNUNET_TIME_Relative timeout,
1090 GNUNET_DATASTORE_ContinuationWithStatus cont,
1093 struct GNUNET_DATASTORE_QueueEntry *qe;
1094 struct UpdateMessage *um;
1095 union QueueContext qc;
1098 cont = &drop_status_cont;
1100 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1101 "Asked to update entry %llu raising priority by %u and expiration to %llu\n",
1103 (unsigned int) priority,
1104 (unsigned long long) expiration.abs_value);
1107 qc.sc.cont_cls = cont_cls;
1108 qe = make_queue_entry (h, sizeof(struct UpdateMessage),
1109 queue_priority, max_queue_size, timeout,
1110 &process_status_message, &qc);
1114 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1115 "Could not create queue entry for UPDATE\n");
1119 GNUNET_STATISTICS_update (h->stats,
1120 gettext_noop ("# UPDATE requests executed"),
1123 um = (struct UpdateMessage*) &qe[1];
1124 um->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_UPDATE);
1125 um->header.size = htons(sizeof (struct UpdateMessage));
1126 um->priority = htonl(priority);
1127 um->expiration = GNUNET_TIME_absolute_hton(expiration);
1128 um->uid = GNUNET_htonll(uid);
1135 * Explicitly remove some content from the database.
1136 * The "cont"inuation will be called with status
1137 * "GNUNET_OK" if content was removed, "GNUNET_NO"
1138 * if no matching entry was found and "GNUNET_SYSERR"
1139 * on all other types of errors.
1141 * @param h handle to the datastore
1142 * @param key key for the value
1143 * @param size number of bytes in data
1144 * @param data content stored
1145 * @param queue_priority ranking of this request in the priority queue
1146 * @param max_queue_size at what queue size should this request be dropped
1147 * (if other requests of higher priority are in the queue)
1148 * @param timeout how long to wait at most for a response
1149 * @param cont continuation to call when done
1150 * @param cont_cls closure for cont
1151 * @return NULL if the entry was not queued, otherwise a handle that can be used to
1152 * cancel; note that even if NULL is returned, the callback will be invoked
1153 * (or rather, will already have been invoked)
1155 struct GNUNET_DATASTORE_QueueEntry *
1156 GNUNET_DATASTORE_remove (struct GNUNET_DATASTORE_Handle *h,
1157 const GNUNET_HashCode *key,
1160 unsigned int queue_priority,
1161 unsigned int max_queue_size,
1162 struct GNUNET_TIME_Relative timeout,
1163 GNUNET_DATASTORE_ContinuationWithStatus cont,
1166 struct GNUNET_DATASTORE_QueueEntry *qe;
1167 struct DataMessage *dm;
1169 union QueueContext qc;
1172 cont = &drop_status_cont;
1174 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1175 "Asked to remove %u bytes under key `%s'\n",
1180 qc.sc.cont_cls = cont_cls;
1181 msize = sizeof(struct DataMessage) + size;
1182 GNUNET_assert (msize < GNUNET_SERVER_MAX_MESSAGE_SIZE);
1183 qe = make_queue_entry (h, msize,
1184 queue_priority, max_queue_size, timeout,
1185 &process_status_message, &qc);
1189 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1190 "Could not create queue entry for REMOVE\n");
1194 GNUNET_STATISTICS_update (h->stats,
1195 gettext_noop ("# REMOVE requests executed"),
1198 dm = (struct DataMessage*) &qe[1];
1199 dm->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_REMOVE);
1200 dm->header.size = htons(msize);
1202 dm->size = htonl(size);
1203 dm->type = htonl(0);
1204 dm->priority = htonl(0);
1205 dm->anonymity = htonl(0);
1206 dm->uid = GNUNET_htonll(0);
1207 dm->expiration = GNUNET_TIME_absolute_hton(GNUNET_TIME_UNIT_ZERO_ABS);
1209 memcpy (&dm[1], data, size);
1216 * Type of a function to call when we receive a message
1219 * @param cls closure
1220 * @param msg message received, NULL on timeout or fatal error
1223 process_result_message (void *cls,
1224 const struct GNUNET_MessageHeader *msg)
1226 struct GNUNET_DATASTORE_Handle *h = cls;
1227 struct GNUNET_DATASTORE_QueueEntry *qe;
1228 struct ResultContext rc;
1229 const struct DataMessage *dm;
1231 h->in_receive = GNUNET_NO;
1232 if (h->skip_next_messages > 0)
1234 h->skip_next_messages--;
1241 GNUNET_assert (NULL != qe);
1242 if (qe->was_transmitted == GNUNET_YES)
1245 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1246 _("Failed to receive response from database.\n"));
1248 free_queue_entry (qe);
1249 if (rc.proc != NULL)
1250 rc.proc (rc.proc_cls,
1251 NULL, 0, NULL, 0, 0, 0,
1252 GNUNET_TIME_UNIT_ZERO_ABS, 0);
1258 if (ntohs(msg->type) == GNUNET_MESSAGE_TYPE_DATASTORE_DATA_END)
1260 GNUNET_break (ntohs(msg->size) == sizeof(struct GNUNET_MessageHeader));
1263 GNUNET_assert (GNUNET_YES == qe->was_transmitted);
1264 free_queue_entry (qe);
1266 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1267 "Received end of result set, new queue size is %u\n",
1270 if (rc.proc != NULL)
1271 rc.proc (rc.proc_cls,
1272 NULL, 0, NULL, 0, 0, 0,
1273 GNUNET_TIME_UNIT_ZERO_ABS, 0);
1274 h->retry_time.rel_value = 0;
1275 h->result_count = 0;
1281 GNUNET_assert (GNUNET_YES == qe->was_transmitted);
1282 if ( (ntohs(msg->size) < sizeof(struct DataMessage)) ||
1283 (ntohs(msg->type) != GNUNET_MESSAGE_TYPE_DATASTORE_DATA) ||
1284 (ntohs(msg->size) != sizeof(struct DataMessage) + ntohl (((const struct DataMessage*)msg)->size)) )
1287 free_queue_entry (qe);
1288 h->retry_time = GNUNET_TIME_UNIT_ZERO;
1290 if (rc.proc != NULL)
1291 rc.proc (rc.proc_cls,
1292 NULL, 0, NULL, 0, 0, 0,
1293 GNUNET_TIME_UNIT_ZERO_ABS, 0);
1296 GNUNET_STATISTICS_update (h->stats,
1297 gettext_noop ("# Results received"),
1300 dm = (const struct DataMessage*) msg;
1302 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1303 "Received result %llu with type %u and size %u with key %s\n",
1304 (unsigned long long) GNUNET_ntohll(dm->uid),
1307 GNUNET_h2s(&dm->key));
1309 free_queue_entry (qe);
1310 h->retry_time.rel_value = 0;
1312 if (rc.proc != NULL)
1313 rc.proc (rc.proc_cls,
1318 ntohl(dm->priority),
1319 ntohl(dm->anonymity),
1320 GNUNET_TIME_absolute_ntoh(dm->expiration),
1321 GNUNET_ntohll(dm->uid));
1326 * Get a random value from the datastore for content replication.
1327 * Returns a single, random value among those with the highest
1328 * replication score, lowering positive replication scores by one for
1329 * the chosen value (if only content with a replication score exists,
1330 * a random value is returned and replication scores are not changed).
1332 * @param h handle to the datastore
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 proc function to call on a random value; it
1338 * will be called once with a value (if available)
1339 * and always once with a value of NULL.
1340 * @param proc_cls closure for proc
1341 * @return NULL if the entry was not queued, otherwise a handle that can be used to
1344 struct GNUNET_DATASTORE_QueueEntry *
1345 GNUNET_DATASTORE_get_for_replication (struct GNUNET_DATASTORE_Handle *h,
1346 unsigned int queue_priority,
1347 unsigned int max_queue_size,
1348 struct GNUNET_TIME_Relative timeout,
1349 GNUNET_DATASTORE_DatumProcessor proc,
1352 struct GNUNET_DATASTORE_QueueEntry *qe;
1353 struct GNUNET_MessageHeader *m;
1354 union QueueContext qc;
1356 GNUNET_assert (NULL != proc);
1358 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1359 "Asked to get replication entry in %llu ms\n",
1360 (unsigned long long) timeout.rel_value);
1363 qc.rc.proc_cls = proc_cls;
1364 qe = make_queue_entry (h, sizeof(struct GNUNET_MessageHeader),
1365 queue_priority, max_queue_size, timeout,
1366 &process_result_message, &qc);
1370 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1371 "Could not create queue entry for GET REPLICATION\n");
1375 GNUNET_STATISTICS_update (h->stats,
1376 gettext_noop ("# GET REPLICATION requests executed"),
1379 m = (struct GNUNET_MessageHeader*) &qe[1];
1380 m->type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_GET_REPLICATION);
1381 m->size = htons(sizeof (struct GNUNET_MessageHeader));
1388 * Get a single zero-anonymity value from the datastore.
1390 * @param h handle to the datastore
1391 * @param offset offset of the result (mod #num-results); set to
1392 * a random 64-bit value initially; then increment by
1393 * one each time; detect that all results have been found by uid
1394 * being again the first uid ever returned.
1395 * @param queue_priority ranking of this request in the priority queue
1396 * @param max_queue_size at what queue size should this request be dropped
1397 * (if other requests of higher priority are in the queue)
1398 * @param timeout how long to wait at most for a response
1399 * @param type allowed type for the operation (never zero)
1400 * @param proc function to call on a random value; it
1401 * will be called once with a value (if available)
1402 * or with NULL if none value exists.
1403 * @param proc_cls closure for proc
1404 * @return NULL if the entry was not queued, otherwise a handle that can be used to
1407 struct GNUNET_DATASTORE_QueueEntry *
1408 GNUNET_DATASTORE_get_zero_anonymity (struct GNUNET_DATASTORE_Handle *h,
1410 unsigned int queue_priority,
1411 unsigned int max_queue_size,
1412 struct GNUNET_TIME_Relative timeout,
1413 enum GNUNET_BLOCK_Type type,
1414 GNUNET_DATASTORE_DatumProcessor proc,
1417 struct GNUNET_DATASTORE_QueueEntry *qe;
1418 struct GetZeroAnonymityMessage *m;
1419 union QueueContext qc;
1421 GNUNET_assert (NULL != proc);
1422 GNUNET_assert (type != GNUNET_BLOCK_TYPE_ANY);
1424 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1425 "Asked to get %llu-th zero-anonymity entry of type %d in %llu ms\n",
1426 (unsigned long long) offset,
1428 (unsigned long long) timeout.rel_value);
1431 qc.rc.proc_cls = proc_cls;
1432 qe = make_queue_entry (h, sizeof(struct GetZeroAnonymityMessage),
1433 queue_priority, max_queue_size, timeout,
1434 &process_result_message, &qc);
1438 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1439 "Could not create queue entry for zero-anonymity procation\n");
1443 GNUNET_STATISTICS_update (h->stats,
1444 gettext_noop ("# GET ZERO ANONYMITY requests executed"),
1447 m = (struct GetZeroAnonymityMessage*) &qe[1];
1448 m->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_GET_ZERO_ANONYMITY);
1449 m->header.size = htons(sizeof (struct GetZeroAnonymityMessage));
1450 m->type = htonl ((uint32_t) type);
1451 m->offset = GNUNET_htonll (offset);
1458 * Get a result for a particular key from the datastore. The processor
1459 * will only be called once.
1461 * @param h handle to the datastore
1462 * @param offset offset of the result (mod #num-results); set to
1463 * a random 64-bit value initially; then increment by
1464 * one each time; detect that all results have been found by uid
1465 * being again the first uid ever returned.
1466 * @param key maybe NULL (to match all entries)
1467 * @param type desired type, 0 for any
1468 * @param queue_priority ranking of this request in the priority queue
1469 * @param max_queue_size at what queue size should this request be dropped
1470 * (if other requests of higher priority are in the queue)
1471 * @param timeout how long to wait at most for a response
1472 * @param proc function to call on each matching value;
1473 * will be called once with a NULL value at the end
1474 * @param proc_cls closure for proc
1475 * @return NULL if the entry was not queued, otherwise a handle that can be used to
1478 struct GNUNET_DATASTORE_QueueEntry *
1479 GNUNET_DATASTORE_get_key (struct GNUNET_DATASTORE_Handle *h,
1481 const GNUNET_HashCode * key,
1482 enum GNUNET_BLOCK_Type type,
1483 unsigned int queue_priority,
1484 unsigned int max_queue_size,
1485 struct GNUNET_TIME_Relative timeout,
1486 GNUNET_DATASTORE_DatumProcessor proc,
1489 struct GNUNET_DATASTORE_QueueEntry *qe;
1490 struct GetMessage *gm;
1491 union QueueContext qc;
1493 GNUNET_assert (NULL != proc);
1495 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1496 "Asked to look for data of type %u under key `%s'\n",
1497 (unsigned int) type,
1501 qc.rc.proc_cls = proc_cls;
1502 qe = make_queue_entry (h, sizeof(struct GetMessage),
1503 queue_priority, max_queue_size, timeout,
1504 &process_result_message, &qc);
1508 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1509 "Could not queue request for `%s'\n",
1514 GNUNET_STATISTICS_update (h->stats,
1515 gettext_noop ("# GET requests executed"),
1518 gm = (struct GetMessage*) &qe[1];
1519 gm->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_GET);
1520 gm->type = htonl(type);
1521 gm->offset = GNUNET_htonll (offset);
1524 gm->header.size = htons(sizeof (struct GetMessage));
1529 gm->header.size = htons(sizeof (struct GetMessage) - sizeof(GNUNET_HashCode));
1537 * Cancel a datastore operation. The final callback from the
1538 * operation must not have been done yet.
1540 * @param qe operation to cancel
1543 GNUNET_DATASTORE_cancel (struct GNUNET_DATASTORE_QueueEntry *qe)
1545 struct GNUNET_DATASTORE_Handle *h;
1547 GNUNET_assert (GNUNET_SYSERR != qe->was_transmitted);
1550 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1551 "Pending DATASTORE request %p cancelled (%d, %d)\n",
1553 qe->was_transmitted,
1554 h->queue_head == qe);
1556 if (GNUNET_YES == qe->was_transmitted)
1558 free_queue_entry (qe);
1559 h->skip_next_messages++;
1562 free_queue_entry (qe);
1567 /* end of datastore_api.c */