2 This file is part of GNUnet
3 (C) 2004, 2005, 2006, 2007, 2009 Christian Grothoff (and other contributing authors)
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6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 2, or (at your
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11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
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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
24 * @author Christian Grothoff
27 #include "gnunet_datastore_service.h"
28 #include "datastore.h"
31 * Handle to the datastore service. Followed
32 * by 65536 bytes used for storing messages.
34 struct GNUNET_DATASTORE_Handle
40 const struct GNUNET_CONFIGURATION_Handle *cfg;
45 struct GNUNET_SCHEDULER_Handle *sched;
48 * Current connection to the datastore service.
50 struct GNUNET_CLIENT_Connection *client;
53 * Current response processor (NULL if we are not waiting for a
54 * response). The specific type depends on the kind of message we
60 * Closure for response_proc.
62 void *response_proc_cls;
65 * Timeout for the current operation.
67 struct GNUNET_TIME_Absolute timeout;
70 * Number of bytes in the message following
71 * this struct, 0 if we have no request pending.
79 * Connect to the datastore service.
81 * @param cfg configuration to use
82 * @param sched scheduler to use
83 * @return handle to use to access the service
85 struct GNUNET_DATASTORE_Handle *GNUNET_DATASTORE_connect (const struct
86 GNUNET_CONFIGURATION_Handle
89 GNUNET_SCHEDULER_Handle
92 struct GNUNET_CLIENT_Connection *c;
93 struct GNUNET_DATASTORE_Handle *h;
95 c = GNUNET_CLIENT_connect (sched, "datastore", cfg);
97 return NULL; /* oops */
98 h = GNUNET_malloc (sizeof(struct GNUNET_DATASTORE_Handle) +
99 GNUNET_SERVER_MAX_MESSAGE_SIZE);
108 * Transmit DROP message to datastore service.
111 transmit_drop (void *cls,
112 size_t size, void *buf)
114 struct GNUNET_DATASTORE_Handle *h = cls;
115 struct GNUNET_MessageHeader *hdr;
119 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
120 _("Failed to transmit request to drop database.\n"));
121 GNUNET_DATASTORE_disconnect (h, GNUNET_NO);
124 GNUNET_assert (size >= sizeof(struct GNUNET_MessageHeader));
126 hdr->size = htons(sizeof(struct GNUNET_MessageHeader));
127 hdr->type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_DROP);
128 GNUNET_DATASTORE_disconnect (h, GNUNET_NO);
129 return sizeof(struct GNUNET_MessageHeader);
134 * Disconnect from the datastore service (and free
135 * associated resources).
137 * @param h handle to the datastore
138 * @param drop set to GNUNET_YES to delete all data in datastore (!)
140 void GNUNET_DATASTORE_disconnect (struct GNUNET_DATASTORE_Handle *h,
143 GNUNET_assert (0 == h->message_size);
144 GNUNET_assert (NULL == h->response_proc);
145 if ( (GNUNET_YES == drop) &&
146 (h->client != NULL) )
149 GNUNET_CLIENT_notify_transmit_ready (h->client,
150 sizeof(struct GNUNET_MessageHeader),
151 GNUNET_TIME_UNIT_MINUTES,
157 if (h->client != NULL)
158 GNUNET_CLIENT_disconnect (h->client);
164 * Type of a function to call when we receive a message
165 * from the service. This specific function is used
166 * to handle messages of type "struct StatusMessage".
169 * @param msg message received, NULL on timeout or fatal error
172 with_status_response_handler (void *cls,
174 GNUNET_MessageHeader * msg)
176 struct GNUNET_DATASTORE_Handle *h = cls;
177 GNUNET_DATASTORE_ContinuationWithStatus cont = h->response_proc;
178 const struct StatusMessage *sm;
184 h->response_proc = NULL;
185 GNUNET_CLIENT_disconnect (h->client);
186 h->client = GNUNET_CLIENT_connect (h->sched, "datastore", h->cfg);
187 cont (h->response_proc_cls,
189 _("Timeout trying to read response from datastore service\n"));
192 if ( (ntohs(msg->size) < sizeof(struct StatusMessage)) ||
193 (ntohs(msg->type) != GNUNET_MESSAGE_TYPE_DATASTORE_STATUS) )
196 h->response_proc = NULL;
197 GNUNET_CLIENT_disconnect (h->client);
198 h->client = GNUNET_CLIENT_connect (h->sched, "datastore", h->cfg);
199 cont (h->response_proc_cls,
201 _("Error reading response from datastore service\n"));
204 sm = (const struct StatusMessage*) msg;
205 status = ntohl(sm->status);
207 if (ntohs(msg->size) > sizeof(struct StatusMessage))
209 emsg = (const char*) &sm[1];
210 if (emsg[ntohs(msg->size) - sizeof(struct StatusMessage) - 1] != '\0')
213 emsg = _("Invalid error message received from datastore service");
216 if ( (status == GNUNET_SYSERR) &&
220 emsg = _("Invalid error message received from datastore service");
222 h->response_proc = NULL;
224 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
225 "Received status %d/%s\n",
229 cont (h->response_proc_cls,
236 * Transmit message to datastore service and then
237 * read a status message.
239 * @param cls closure with handle to datastore
240 * @param size number of bytes we can transmit at most
241 * @param buf where to write transmission, NULL on
243 * @return number of bytes copied to buf
246 transmit_get_status (void *cls,
250 struct GNUNET_DATASTORE_Handle *h = cls;
251 GNUNET_DATASTORE_ContinuationWithStatus cont = h->response_proc;
257 h->response_proc = NULL;
258 cont (h->response_proc_cls,
260 gettext_noop ("Error transmitting message to datastore service.\n"));
263 msize = h->message_size;
264 GNUNET_assert (msize <= size);
265 memcpy (buf, &h[1], msize);
267 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
268 "Transmitted %u byte message to datastore service, now waiting for status.\n",
272 GNUNET_CLIENT_receive (h->client,
273 &with_status_response_handler,
275 GNUNET_TIME_absolute_get_remaining (h->timeout));
281 * Helper function that will initiate the
282 * transmission of a message to the datastore
283 * service. The message must already be prepared
284 * and stored in the buffer at the end of the
285 * handle. The message must be of a type that
286 * expects a "StatusMessage" in response.
288 * @param h handle to the service with prepared message
289 * @param cont function to call with result
290 * @param cont_cls closure
291 * @param timeout timeout for the operation
294 transmit_for_status (struct GNUNET_DATASTORE_Handle *h,
295 GNUNET_DATASTORE_ContinuationWithStatus cont,
297 struct GNUNET_TIME_Relative timeout)
299 const struct GNUNET_MessageHeader *hdr;
302 GNUNET_assert (cont != NULL);
303 hdr = (const struct GNUNET_MessageHeader*) &h[1];
304 msize = ntohs(hdr->size);
306 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
307 "Transmitting %u byte message of type %u to datastore service\n",
311 GNUNET_assert (h->response_proc == NULL);
312 h->response_proc = cont;
313 h->response_proc_cls = cont_cls;
314 h->timeout = GNUNET_TIME_relative_to_absolute (timeout);
315 h->message_size = msize;
316 if (NULL == GNUNET_CLIENT_notify_transmit_ready (h->client,
319 &transmit_get_status,
323 h->response_proc = NULL;
327 gettext_noop ("Not ready to transmit request to datastore service"));
333 * Store an item in the datastore. If the item is already present,
334 * the priorities are summed up and the higher expiration time and
335 * lower anonymity level is used.
337 * @param h handle to the datastore
338 * @param key key for the value
339 * @param size number of bytes in data
340 * @param data content stored
341 * @param type type of the content
342 * @param priority priority of the content
343 * @param anonymity anonymity-level for the content
344 * @param expiration expiration time for the content
345 * @param timeout timeout for the operation
346 * @param cont continuation to call when done
347 * @param cont_cls closure for cont
350 GNUNET_DATASTORE_put (struct GNUNET_DATASTORE_Handle *h,
352 const GNUNET_HashCode * key,
358 struct GNUNET_TIME_Absolute expiration,
359 struct GNUNET_TIME_Relative timeout,
360 GNUNET_DATASTORE_ContinuationWithStatus cont,
363 struct DataMessage *dm;
367 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
368 "Asked to put %u bytes of data\n",
371 msize = sizeof(struct DataMessage) + size;
372 GNUNET_assert (msize <= GNUNET_SERVER_MAX_MESSAGE_SIZE);
373 dm = (struct DataMessage*) &h[1];
374 dm->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_PUT);
375 dm->header.size = htons(msize);
376 dm->rid = htonl(rid);
377 dm->size = htonl(size);
378 dm->type = htonl(type);
379 dm->priority = htonl(priority);
380 dm->anonymity = htonl(anonymity);
381 dm->uid = GNUNET_htonll(0);
382 dm->expiration = GNUNET_TIME_absolute_hton(expiration);
384 memcpy (&dm[1], data, size);
385 transmit_for_status (h, cont, cont_cls, timeout);
390 * Reserve space in the datastore. This function should be used
391 * to avoid "out of space" failures during a longer sequence of "put"
392 * operations (for example, when a file is being inserted).
394 * @param h handle to the datastore
395 * @param amount how much space (in bytes) should be reserved (for content only)
396 * @param entries how many entries will be created (to calculate per-entry overhead)
397 * @param cont continuation to call when done; "success" will be set to
398 * a positive reservation value if space could be reserved.
399 * @param cont_cls closure for cont
400 * @param timeout how long to wait at most for a response
403 GNUNET_DATASTORE_reserve (struct GNUNET_DATASTORE_Handle *h,
406 GNUNET_DATASTORE_ContinuationWithStatus cont,
408 struct GNUNET_TIME_Relative timeout)
410 struct ReserveMessage *rm;
412 rm = (struct ReserveMessage*) &h[1];
413 rm->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_RESERVE);
414 rm->header.size = htons(sizeof (struct ReserveMessage));
415 rm->entries = htonl(entries);
416 rm->amount = GNUNET_htonll(amount);
417 transmit_for_status (h, cont, cont_cls, timeout);
422 * Signal that all of the data for which a reservation was made has
423 * been stored and that whatever excess space might have been reserved
424 * can now be released.
426 * @param h handle to the datastore
427 * @param rid reservation ID (value of "success" in original continuation
428 * from the "reserve" function).
429 * @param cont continuation to call when done
430 * @param cont_cls closure for cont
431 * @param timeout how long to wait at most for a response
434 GNUNET_DATASTORE_release_reserve (struct GNUNET_DATASTORE_Handle *h,
436 GNUNET_DATASTORE_ContinuationWithStatus cont,
438 struct GNUNET_TIME_Relative timeout)
440 struct ReleaseReserveMessage *rrm;
442 rrm = (struct ReleaseReserveMessage*) &h[1];
443 rrm->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_RELEASE_RESERVE);
444 rrm->header.size = htons(sizeof (struct ReleaseReserveMessage));
445 rrm->rid = htonl(rid);
446 transmit_for_status (h, cont, cont_cls, timeout);
451 * Update a value in the datastore.
453 * @param h handle to the datastore
454 * @param uid identifier for the value
455 * @param priority how much to increase the priority of the value
456 * @param expiration new expiration value should be MAX of existing and this argument
457 * @param cont continuation to call when done
458 * @param cont_cls closure for cont
459 * @param timeout how long to wait at most for a response
462 GNUNET_DATASTORE_update (struct GNUNET_DATASTORE_Handle *h,
463 unsigned long long uid,
465 struct GNUNET_TIME_Absolute expiration,
466 GNUNET_DATASTORE_ContinuationWithStatus cont,
468 struct GNUNET_TIME_Relative timeout)
470 struct UpdateMessage *um;
472 um = (struct UpdateMessage*) &h[1];
473 um->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_UPDATE);
474 um->header.size = htons(sizeof (struct UpdateMessage));
475 um->priority = htonl(priority);
476 um->expiration = GNUNET_TIME_absolute_hton(expiration);
477 um->uid = GNUNET_htonll(uid);
478 transmit_for_status (h, cont, cont_cls, timeout);
485 * Type of a function to call when we receive a message
486 * from the service. This specific function is used
487 * to handle messages of type "struct DataMessage".
490 * @param msg message received, NULL on timeout or fatal error
493 with_result_response_handler (void *cls,
495 GNUNET_MessageHeader * msg)
497 struct GNUNET_DATASTORE_Handle *h = cls;
498 GNUNET_DATASTORE_Iterator cont = h->response_proc;
499 const struct DataMessage *dm;
504 h->response_proc = NULL;
505 GNUNET_CLIENT_disconnect (h->client);
506 h->client = GNUNET_CLIENT_connect (h->sched, "datastore", h->cfg);
507 cont (h->response_proc_cls,
508 NULL, 0, NULL, 0, 0, 0,
509 GNUNET_TIME_UNIT_ZERO_ABS, 0);
512 if (ntohs(msg->type) == GNUNET_MESSAGE_TYPE_DATASTORE_DATA_END)
514 GNUNET_break (ntohs(msg->size) == sizeof(struct GNUNET_MessageHeader));
515 h->response_proc = NULL;
517 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
518 "Received end of result set\n");
520 cont (h->response_proc_cls,
521 NULL, 0, NULL, 0, 0, 0,
522 GNUNET_TIME_UNIT_ZERO_ABS, 0);
525 if ( (ntohs(msg->size) < sizeof(struct DataMessage)) ||
526 (ntohs(msg->type) != GNUNET_MESSAGE_TYPE_DATASTORE_DATA) )
529 GNUNET_CLIENT_disconnect (h->client);
530 h->client = GNUNET_CLIENT_connect (h->sched, "datastore", h->cfg);
531 h->response_proc = NULL;
532 cont (h->response_proc_cls,
533 NULL, 0, NULL, 0, 0, 0,
534 GNUNET_TIME_UNIT_ZERO_ABS, 0);
537 dm = (const struct DataMessage*) msg;
538 msize = ntohl(dm->size);
539 if (ntohs(msg->size) != msize + sizeof(struct DataMessage))
542 GNUNET_CLIENT_disconnect (h->client);
543 h->client = GNUNET_CLIENT_connect (h->sched, "datastore", h->cfg);
544 h->response_proc = NULL;
545 cont (h->response_proc_cls,
546 NULL, 0, NULL, 0, 0, 0,
547 GNUNET_TIME_UNIT_ZERO_ABS, 0);
551 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
552 "Received result %llu with type %u and size %u with key %s\n",
553 (unsigned long long) GNUNET_ntohll(dm->uid),
556 GNUNET_h2s(&dm->key));
558 cont (h->response_proc_cls,
564 ntohl(dm->anonymity),
565 GNUNET_TIME_absolute_ntoh(dm->expiration),
566 GNUNET_ntohll(dm->uid));
567 GNUNET_CLIENT_receive (h->client,
568 &with_result_response_handler,
570 GNUNET_TIME_absolute_get_remaining (h->timeout));
575 * Transmit message to datastore service and then
576 * read a result message.
578 * @param cls closure with handle to datastore
579 * @param size number of bytes we can transmit at most
580 * @param buf where to write transmission, NULL on
582 * @return number of bytes copied to buf
585 transmit_get_result (void *cls,
589 struct GNUNET_DATASTORE_Handle *h = cls;
590 GNUNET_DATASTORE_ContinuationWithStatus cont = h->response_proc;
595 h->response_proc = NULL;
597 cont (h->response_proc_cls,
599 gettext_noop ("Error transmitting message to datastore service.\n"));
602 msize = h->message_size;
603 GNUNET_assert (msize <= size);
604 memcpy (buf, &h[1], msize);
606 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
607 "Transmitted %u byte message to datastore service, now waiting for result.\n",
611 GNUNET_CLIENT_receive (h->client,
612 &with_result_response_handler,
614 GNUNET_TIME_absolute_get_remaining (h->timeout));
620 * Helper function that will initiate the
621 * transmission of a message to the datastore
622 * service. The message must already be prepared
623 * and stored in the buffer at the end of the
624 * handle. The message must be of a type that
625 * expects a "DataMessage" in response.
627 * @param h handle to the service with prepared message
628 * @param cont function to call with result
629 * @param cont_cls closure
630 * @param timeout timeout for the operation
633 transmit_for_result (struct GNUNET_DATASTORE_Handle *h,
634 GNUNET_DATASTORE_Iterator cont,
636 struct GNUNET_TIME_Relative timeout)
638 const struct GNUNET_MessageHeader *hdr;
641 GNUNET_assert (cont != NULL);
642 hdr = (const struct GNUNET_MessageHeader*) &h[1];
643 msize = ntohs(hdr->size);
645 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
646 "Transmitting %u byte message of type %u to datastore service\n",
650 GNUNET_assert (h->response_proc == NULL);
651 h->response_proc = cont;
652 h->response_proc_cls = cont_cls;
653 h->timeout = GNUNET_TIME_relative_to_absolute (timeout);
654 h->message_size = msize;
655 if (NULL == GNUNET_CLIENT_notify_transmit_ready (h->client,
658 &transmit_get_result,
662 h->response_proc = NULL;
664 cont (h->response_proc_cls,
665 NULL, 0, NULL, 0, 0, 0,
666 GNUNET_TIME_UNIT_ZERO_ABS, 0);
672 * Iterate over the results for a particular key
675 * @param h handle to the datastore
676 * @param key maybe NULL (to match all entries)
677 * @param type desired type, 0 for any
678 * @param iter function to call on each matching value;
679 * will be called once with a NULL value at the end
680 * @param iter_cls closure for iter
681 * @param timeout how long to wait at most for a response
684 GNUNET_DATASTORE_get (struct GNUNET_DATASTORE_Handle *h,
685 const GNUNET_HashCode * key,
687 GNUNET_DATASTORE_Iterator iter, void *iter_cls,
688 struct GNUNET_TIME_Relative timeout)
690 struct GetMessage *gm;
692 gm = (struct GetMessage*) &h[1];
693 gm->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_GET);
694 gm->type = htonl(type);
697 gm->header.size = htons(sizeof (struct GetMessage));
702 gm->header.size = htons(sizeof (struct GetMessage) - sizeof(GNUNET_HashCode));
704 transmit_for_result (h, iter, iter_cls, timeout);
709 * Get a random value from the datastore.
711 * @param h handle to the datastore
712 * @param iter function to call on a random value; it
713 * will be called exactly once; if no values
714 * are available, the value will be NULL.
715 * @param iter_cls closure for iter
716 * @param timeout how long to wait at most for a response
719 GNUNET_DATASTORE_get_random (struct GNUNET_DATASTORE_Handle *h,
720 GNUNET_DATASTORE_Iterator iter, void *iter_cls,
721 struct GNUNET_TIME_Relative timeout)
723 struct GNUNET_MessageHeader *m;
725 m = (struct GNUNET_MessageHeader*) &h[1];
726 m->type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_GET_RANDOM);
727 m->size = htons(sizeof (struct GNUNET_MessageHeader));
728 transmit_for_result (h, iter, iter_cls, timeout);
733 * Explicitly remove some content from the database.
735 * @param h handle to the datastore
736 * @param key key for the value
737 * @param size number of bytes in data
738 * @param data content stored
739 * @param cont continuation to call when done
740 * @param cont_cls closure for cont
741 * @param timeout how long to wait at most for a response
744 GNUNET_DATASTORE_remove (struct GNUNET_DATASTORE_Handle *h,
745 const GNUNET_HashCode * key,
746 uint32_t size, const void *data,
747 GNUNET_DATASTORE_ContinuationWithStatus cont,
749 struct GNUNET_TIME_Relative timeout)
751 struct DataMessage *dm;
754 msize = sizeof(struct DataMessage) + size;
755 GNUNET_assert (msize <= GNUNET_SERVER_MAX_MESSAGE_SIZE);
756 dm = (struct DataMessage*) &h[1];
757 dm->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_REMOVE);
758 dm->header.size = htons(msize);
760 dm->size = htonl(size);
762 dm->priority = htonl(0);
763 dm->anonymity = htonl(0);
764 dm->uid = GNUNET_htonll(0);
765 dm->expiration = GNUNET_TIME_absolute_hton(GNUNET_TIME_UNIT_ZERO_ABS);
767 memcpy (&dm[1], data, size);
768 transmit_for_status (h, cont, cont_cls, timeout);
772 /* end of datastore_api.c */