/*
This file is part of GNUnet
- (C) 2004, 2005, 2006, 2007, 2009 Christian Grothoff (and other contributing authors)
+ (C) 2004, 2005, 2006, 2007, 2009, 2010 Christian Grothoff (and other contributing authors)
GNUnet is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published
- by the Free Software Foundation; either version 2, or (at your
+ by the Free Software Foundation; either version 3, or (at your
option) any later version.
GNUnet is distributed in the hope that it will be useful, but
/**
* @file datastore/datastore_api.c
- * @brief Management for the datastore for files stored on a GNUnet node
+ * @brief Management for the datastore for files stored on a GNUnet node. Implements
+ * a priority queue for requests (with timeouts).
* @author Christian Grothoff
*/
-
#include "platform.h"
+#include "gnunet_arm_service.h"
+#include "gnunet_constants.h"
#include "gnunet_datastore_service.h"
#include "datastore.h"
+
+/**
+ * Context for processing status messages.
+ */
+struct StatusContext
+{
+ /**
+ * Continuation to call with the status.
+ */
+ GNUNET_DATASTORE_ContinuationWithStatus cont;
+
+ /**
+ * Closure for cont.
+ */
+ void *cont_cls;
+
+};
+
+
+/**
+ * Context for processing result messages.
+ */
+struct ResultContext
+{
+ /**
+ * Iterator to call with the result.
+ */
+ GNUNET_DATASTORE_Iterator iter;
+
+ /**
+ * Closure for iter.
+ */
+ void *iter_cls;
+
+};
+
+
+/**
+ * Context for a queue operation.
+ */
+union QueueContext
+{
+
+ struct StatusContext sc;
+
+ struct ResultContext rc;
+
+};
+
+
+
/**
- * Handle to the datastore service.
+ * Entry in our priority queue.
+ */
+struct GNUNET_DATASTORE_QueueEntry
+{
+
+ /**
+ * This is a linked list.
+ */
+ struct GNUNET_DATASTORE_QueueEntry *next;
+
+ /**
+ * This is a linked list.
+ */
+ struct GNUNET_DATASTORE_QueueEntry *prev;
+
+ /**
+ * Handle to the master context.
+ */
+ struct GNUNET_DATASTORE_Handle *h;
+
+ /**
+ * Response processor (NULL if we are not waiting for a response).
+ * This struct should be used for the closure, function-specific
+ * arguments can be passed via 'qc'.
+ */
+ GNUNET_CLIENT_MessageHandler response_proc;
+
+ /**
+ * Function to call after transmission of the request.
+ */
+ GNUNET_DATASTORE_ContinuationWithStatus cont;
+
+ /**
+ * Closure for 'cont'.
+ */
+ void *cont_cls;
+
+ /**
+ * Context for the operation.
+ */
+ union QueueContext qc;
+
+ /**
+ * Task for timeout signalling.
+ */
+ GNUNET_SCHEDULER_TaskIdentifier task;
+
+ /**
+ * Timeout for the current operation.
+ */
+ struct GNUNET_TIME_Absolute timeout;
+
+ /**
+ * Priority in the queue.
+ */
+ unsigned int priority;
+
+ /**
+ * Maximum allowed length of queue (otherwise
+ * this request should be discarded).
+ */
+ unsigned int max_queue;
+
+ /**
+ * Number of bytes in the request message following
+ * this struct. 32-bit value for nicer memory
+ * access (and overall struct alignment).
+ */
+ uint32_t message_size;
+
+ /**
+ * Has this message been transmitted to the service?
+ * Only ever GNUNET_YES for the head of the queue.
+ * Note that the overall struct should end at a
+ * multiple of 64 bits.
+ */
+ int32_t was_transmitted;
+
+};
+
+/**
+ * Handle to the datastore service.
*/
struct GNUNET_DATASTORE_Handle
{
+
+ /**
+ * Our configuration.
+ */
+ const struct GNUNET_CONFIGURATION_Handle *cfg;
+
+ /**
+ * Our scheduler.
+ */
+ struct GNUNET_SCHEDULER_Handle *sched;
+
+ /**
+ * Current connection to the datastore service.
+ */
+ struct GNUNET_CLIENT_Connection *client;
+
+ /**
+ * Current transmit handle.
+ */
+ struct GNUNET_CLIENT_TransmitHandle *th;
+
+ /**
+ * Current head of priority queue.
+ */
+ struct GNUNET_DATASTORE_QueueEntry *queue_head;
+
+ /**
+ * Current tail of priority queue.
+ */
+ struct GNUNET_DATASTORE_QueueEntry *queue_tail;
+
+ /**
+ * Task for trying to reconnect.
+ */
+ GNUNET_SCHEDULER_TaskIdentifier reconnect_task;
+
+ /**
+ * How quickly should we retry? Used for exponential back-off on
+ * connect-errors.
+ */
+ struct GNUNET_TIME_Relative retry_time;
+
+ /**
+ * Number of entries in the queue.
+ */
+ unsigned int queue_size;
+
+ /**
+ * Are we currently trying to receive from the service?
+ */
+ int in_receive;
+
};
+
/**
* Connect to the datastore service.
*
* @param sched scheduler to use
* @return handle to use to access the service
*/
-struct GNUNET_DATASTORE_Handle *GNUNET_DATASTORE_connect (struct
- GNUNET_CONFIGURATION_Handle
- *cfg,
- struct
- GNUNET_SCHEDULER_Handle
- *sched)
+struct GNUNET_DATASTORE_Handle *
+GNUNET_DATASTORE_connect (const struct
+ GNUNET_CONFIGURATION_Handle
+ *cfg,
+ struct
+ GNUNET_SCHEDULER_Handle
+ *sched)
+{
+ struct GNUNET_CLIENT_Connection *c;
+ struct GNUNET_DATASTORE_Handle *h;
+
+ c = GNUNET_CLIENT_connect (sched, "datastore", cfg);
+ if (c == NULL)
+ return NULL; /* oops */
+ h = GNUNET_malloc (sizeof(struct GNUNET_DATASTORE_Handle) +
+ GNUNET_SERVER_MAX_MESSAGE_SIZE - 1);
+ h->client = c;
+ h->cfg = cfg;
+ h->sched = sched;
+ return h;
+}
+
+
+/**
+ * Transmit DROP message to datastore service.
+ *
+ * @param cls the 'struct GNUNET_DATASTORE_Handle'
+ * @param size number of bytes that can be copied to buf
+ * @param buf where to copy the drop message
+ * @return number of bytes written to buf
+ */
+static size_t
+transmit_drop (void *cls,
+ size_t size,
+ void *buf)
{
- return NULL;
+ struct GNUNET_DATASTORE_Handle *h = cls;
+ struct GNUNET_MessageHeader *hdr;
+
+ if (buf == NULL)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+ _("Failed to transmit request to drop database.\n"));
+ GNUNET_DATASTORE_disconnect (h, GNUNET_NO);
+ return 0;
+ }
+ GNUNET_assert (size >= sizeof(struct GNUNET_MessageHeader));
+ hdr = buf;
+ hdr->size = htons(sizeof(struct GNUNET_MessageHeader));
+ hdr->type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_DROP);
+ GNUNET_DATASTORE_disconnect (h, GNUNET_NO);
+ return sizeof(struct GNUNET_MessageHeader);
}
void GNUNET_DATASTORE_disconnect (struct GNUNET_DATASTORE_Handle *h,
int drop)
{
+ struct GNUNET_DATASTORE_QueueEntry *qe;
+
+ if (h->client != NULL)
+ {
+ GNUNET_CLIENT_disconnect (h->client, GNUNET_NO);
+ h->client = NULL;
+ }
+ if (h->reconnect_task != GNUNET_SCHEDULER_NO_TASK)
+ {
+ GNUNET_SCHEDULER_cancel (h->sched,
+ h->reconnect_task);
+ h->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
+ }
+ while (NULL != (qe = h->queue_head))
+ {
+ GNUNET_assert (NULL != qe->response_proc);
+ qe->response_proc (qe, NULL);
+ }
+ if (GNUNET_YES == drop)
+ {
+ h->client = GNUNET_CLIENT_connect (h->sched, "datastore", h->cfg);
+ if (h->client != NULL)
+ {
+ if (NULL !=
+ GNUNET_CLIENT_notify_transmit_ready (h->client,
+ sizeof(struct GNUNET_MessageHeader),
+ GNUNET_TIME_UNIT_MINUTES,
+ GNUNET_YES,
+ &transmit_drop,
+ h))
+ return;
+ GNUNET_CLIENT_disconnect (h->client, GNUNET_NO);
+ }
+ GNUNET_break (0);
+ }
+ GNUNET_free (h);
}
/**
- * Get the current on-disk size of the datastore.
+ * A request has timed out (before being transmitted to the service).
+ *
+ * @param cls the 'struct GNUNET_DATASTORE_QueueEntry'
+ * @param tc scheduler context
+ */
+static void
+timeout_queue_entry (void *cls,
+ const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+ struct GNUNET_DATASTORE_QueueEntry *qe = cls;
+
+ qe->task = GNUNET_SCHEDULER_NO_TASK;
+ GNUNET_assert (qe->was_transmitted == GNUNET_NO);
+ qe->response_proc (qe, NULL);
+}
+
+
+/**
+ * Create a new entry for our priority queue (and possibly discard other entires if
+ * the queue is getting too long).
+ *
* @param h handle to the datastore
- * @return size estimate, -1 if datastore is not available (yet)
+ * @param msize size of the message to queue
+ * @param queue_priority priority of the entry
+ * @param max_queue_size at what queue size should this request be dropped
+ * (if other requests of higher priority are in the queue)
+ * @param timeout timeout for the operation
+ * @param response_proc function to call with replies (can be NULL)
+ * @param qc client context (NOT a closure for response_proc)
+ * @return NULL if the queue is full (and this entry was dropped)
*/
-unsigned long long GNUNET_DATASTORE_size (struct GNUNET_DATASTORE_Handle *h)
+static struct GNUNET_DATASTORE_QueueEntry *
+make_queue_entry (struct GNUNET_DATASTORE_Handle *h,
+ size_t msize,
+ unsigned int queue_priority,
+ unsigned int max_queue_size,
+ struct GNUNET_TIME_Relative timeout,
+ GNUNET_CLIENT_MessageHandler response_proc,
+ const union QueueContext *qc)
{
- return 0;
+ struct GNUNET_DATASTORE_QueueEntry *ret;
+ struct GNUNET_DATASTORE_QueueEntry *pos;
+ unsigned int c;
+
+ c = 0;
+ pos = h->queue_head;
+ while ( (pos != NULL) &&
+ (c < max_queue_size) &&
+ (pos->priority >= queue_priority) )
+ {
+ c++;
+ pos = pos->next;
+ }
+ ret = GNUNET_malloc (sizeof (struct GNUNET_DATASTORE_QueueEntry) + msize);
+ ret->h = h;
+ ret->response_proc = response_proc;
+ ret->qc = *qc;
+ ret->timeout = GNUNET_TIME_relative_to_absolute (timeout);
+ ret->priority = queue_priority;
+ ret->max_queue = max_queue_size;
+ ret->message_size = msize;
+ ret->was_transmitted = GNUNET_NO;
+ if (pos == NULL)
+ {
+ /* append at the tail */
+ pos = h->queue_tail;
+ }
+ else
+ {
+ pos = pos->prev;
+ /* do not insert at HEAD if HEAD query was already
+ transmitted and we are still receiving replies! */
+ if ( (pos == NULL) &&
+ (h->queue_head->was_transmitted) )
+ pos = h->queue_head;
+ }
+ c++;
+ GNUNET_CONTAINER_DLL_insert_after (h->queue_head,
+ h->queue_tail,
+ pos,
+ ret);
+ h->queue_size++;
+ if (c > max_queue_size)
+ {
+ response_proc (ret, NULL);
+ return NULL;
+ }
+ ret->task = GNUNET_SCHEDULER_add_delayed (h->sched,
+ timeout,
+ &timeout_queue_entry,
+ ret);
+ pos = ret->next;
+ while (pos != NULL)
+ {
+ if (pos->max_queue < h->queue_size)
+ {
+ GNUNET_assert (pos->response_proc != NULL);
+ pos->response_proc (pos, NULL);
+ break;
+ }
+ pos = pos->next;
+ }
+ return ret;
+}
+
+
+/**
+ * Process entries in the queue (or do nothing if we are already
+ * doing so).
+ *
+ * @param h handle to the datastore
+ */
+static void
+process_queue (struct GNUNET_DATASTORE_Handle *h);
+
+
+/**
+ * Try reconnecting to the datastore service.
+ *
+ * @param cls the 'struct GNUNET_DATASTORE_Handle'
+ * @param tc scheduler context
+ */
+static void
+try_reconnect (void *cls,
+ const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+ struct GNUNET_DATASTORE_Handle *h = cls;
+
+ if (h->retry_time.value < GNUNET_CONSTANTS_SERVICE_RETRY.value)
+ h->retry_time = GNUNET_CONSTANTS_SERVICE_RETRY;
+ else
+ h->retry_time = GNUNET_TIME_relative_multiply (h->retry_time, 2);
+ if (h->retry_time.value > GNUNET_CONSTANTS_SERVICE_TIMEOUT.value)
+ h->retry_time = GNUNET_CONSTANTS_SERVICE_TIMEOUT;
+ h->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
+ h->client = GNUNET_CLIENT_connect (h->sched, "datastore", h->cfg);
+ if (h->client == NULL)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "DATASTORE reconnect failed (fatally)\n");
+ return;
+ }
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Reconnected to DATASTORE\n");
+#endif
+ process_queue (h);
+}
+
+
+/**
+ * Disconnect from the service and then try reconnecting to the datastore service
+ * after some delay.
+ *
+ * @param h handle to datastore to disconnect and reconnect
+ */
+static void
+do_disconnect (struct GNUNET_DATASTORE_Handle *h)
+{
+ if (h->client == NULL)
+ {
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "client NULL in disconnect, will not try to reconnect\n");
+#endif
+ return;
+ }
+#if 0
+ GNUNET_STATISTICS_update (stats,
+ gettext_noop ("# reconnected to DATASTORE"),
+ 1,
+ GNUNET_NO);
+#endif
+ GNUNET_CLIENT_disconnect (h->client, GNUNET_NO);
+ h->client = NULL;
+ h->reconnect_task = GNUNET_SCHEDULER_add_delayed (h->sched,
+ h->retry_time,
+ &try_reconnect,
+ h);
+}
+
+
+/**
+ * Transmit request from queue to datastore service.
+ *
+ * @param cls the 'struct GNUNET_DATASTORE_Handle'
+ * @param size number of bytes that can be copied to buf
+ * @param buf where to copy the drop message
+ * @return number of bytes written to buf
+ */
+static size_t
+transmit_request (void *cls,
+ size_t size,
+ void *buf)
+{
+ struct GNUNET_DATASTORE_Handle *h = cls;
+ struct GNUNET_DATASTORE_QueueEntry *qe;
+ size_t msize;
+
+ h->th = NULL;
+ if (NULL == (qe = h->queue_head))
+ return 0; /* no entry in queue */
+ if (buf == NULL)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+ _("Failed to transmit request to DATASTORE.\n"));
+ do_disconnect (h);
+ return 0;
+ }
+ if (size < (msize = qe->message_size))
+ {
+ process_queue (h);
+ return 0;
+ }
+ #if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Transmitting %u byte request to DATASTORE\n",
+ msize);
+#endif
+ memcpy (buf, &qe[1], msize);
+ qe->was_transmitted = GNUNET_YES;
+ GNUNET_SCHEDULER_cancel (h->sched,
+ qe->task);
+ qe->task = GNUNET_SCHEDULER_NO_TASK;
+ h->in_receive = GNUNET_YES;
+ GNUNET_CLIENT_receive (h->client,
+ qe->response_proc,
+ qe,
+ GNUNET_TIME_absolute_get_remaining (qe->timeout));
+ return msize;
+}
+
+
+/**
+ * Process entries in the queue (or do nothing if we are already
+ * doing so).
+ *
+ * @param h handle to the datastore
+ */
+static void
+process_queue (struct GNUNET_DATASTORE_Handle *h)
+{
+ struct GNUNET_DATASTORE_QueueEntry *qe;
+
+ if (NULL == (qe = h->queue_head))
+ {
+#if DEBUG_DATASTORE > 1
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Queue empty\n");
+#endif
+ return; /* no entry in queue */
+ }
+ if (qe->was_transmitted == GNUNET_YES)
+ {
+#if DEBUG_DATASTORE > 1
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Head request already transmitted\n");
+#endif
+ return; /* waiting for replies */
+ }
+ if (h->th != NULL)
+ {
+#if DEBUG_DATASTORE > 1
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Pending transmission request\n");
+#endif
+ return; /* request pending */
+ }
+ if (h->client == NULL)
+ {
+#if DEBUG_DATASTORE > 1
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Not connected\n");
+#endif
+ return; /* waiting for reconnect */
+ }
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Queueing %u byte request to DATASTORE\n",
+ qe->message_size);
+#endif
+ h->th = GNUNET_CLIENT_notify_transmit_ready (h->client,
+ qe->message_size,
+ GNUNET_TIME_absolute_get_remaining (qe->timeout),
+ GNUNET_YES,
+ &transmit_request,
+ h);
+}
+
+
+/**
+ * Dummy continuation used to do nothing (but be non-zero).
+ *
+ * @param cls closure
+ * @param result result
+ * @param emsg error message
+ */
+static void
+drop_status_cont (void *cls, int result, const char *emsg)
+{
+ /* do nothing */
+}
+
+
+static void
+free_queue_entry (struct GNUNET_DATASTORE_QueueEntry *qe)
+{
+ struct GNUNET_DATASTORE_Handle *h = qe->h;
+
+ GNUNET_CONTAINER_DLL_remove (h->queue_head,
+ h->queue_tail,
+ qe);
+ if (qe->task != GNUNET_SCHEDULER_NO_TASK)
+ {
+ GNUNET_SCHEDULER_cancel (h->sched,
+ qe->task);
+ qe->task = GNUNET_SCHEDULER_NO_TASK;
+ }
+ h->queue_size--;
+ GNUNET_free (qe);
+}
+
+/**
+ * Type of a function to call when we receive a message
+ * from the service.
+ *
+ * @param cls closure
+ * @param msg message received, NULL on timeout or fatal error
+ */
+static void
+process_status_message (void *cls,
+ const struct
+ GNUNET_MessageHeader * msg)
+{
+ struct GNUNET_DATASTORE_QueueEntry *qe = cls;
+ struct GNUNET_DATASTORE_Handle *h = qe->h;
+ struct StatusContext rc = qe->qc.sc;
+ const struct StatusMessage *sm;
+ const char *emsg;
+ int32_t status;
+ int was_transmitted;
+
+ h->in_receive = GNUNET_NO;
+ was_transmitted = qe->was_transmitted;
+ if (msg == NULL)
+ {
+ free_queue_entry (qe);
+ if (NULL == h->client)
+ return; /* forced disconnect */
+ rc.cont (rc.cont_cls,
+ GNUNET_SYSERR,
+ _("Failed to receive response from database."));
+ if (was_transmitted == GNUNET_YES)
+ do_disconnect (h);
+ return;
+ }
+ GNUNET_assert (GNUNET_YES == qe->was_transmitted);
+ GNUNET_assert (h->queue_head == qe);
+ free_queue_entry (qe);
+ if ( (ntohs(msg->size) < sizeof(struct StatusMessage)) ||
+ (ntohs(msg->type) != GNUNET_MESSAGE_TYPE_DATASTORE_STATUS) )
+ {
+ GNUNET_break (0);
+ h->retry_time = GNUNET_TIME_UNIT_ZERO;
+ do_disconnect (h);
+ rc.cont (rc.cont_cls,
+ GNUNET_SYSERR,
+ _("Error reading response from datastore service"));
+ return;
+ }
+ sm = (const struct StatusMessage*) msg;
+ status = ntohl(sm->status);
+ emsg = NULL;
+ if (ntohs(msg->size) > sizeof(struct StatusMessage))
+ {
+ emsg = (const char*) &sm[1];
+ if (emsg[ntohs(msg->size) - sizeof(struct StatusMessage) - 1] != '\0')
+ {
+ GNUNET_break (0);
+ emsg = _("Invalid error message received from datastore service");
+ }
+ }
+ if ( (status == GNUNET_SYSERR) &&
+ (emsg == NULL) )
+ {
+ GNUNET_break (0);
+ emsg = _("Invalid error message received from datastore service");
+ }
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Received status %d/%s\n",
+ (int) status,
+ emsg);
+#endif
+ rc.cont (rc.cont_cls,
+ status,
+ emsg);
+ process_queue (h);
}
* lower anonymity level is used.
*
* @param h handle to the datastore
+ * @param rid reservation ID to use (from "reserve"); use 0 if no
+ * prior reservation was made
* @param key key for the value
* @param size number of bytes in data
* @param data content stored
* @param priority priority of the content
* @param anonymity anonymity-level for the content
* @param expiration expiration time for the content
+ * @param queue_priority ranking of this request in the priority queue
+ * @param max_queue_size at what queue size should this request be dropped
+ * (if other requests of higher priority are in the queue)
+ * @param timeout timeout for the operation
+ * @param cont continuation to call when done
+ * @param cont_cls closure for cont
+ * @return NULL if the entry was not queued, otherwise a handle that can be used to
+ * cancel; note that even if NULL is returned, the callback will be invoked
+ * (or rather, will already have been invoked)
*/
-void
+struct GNUNET_DATASTORE_QueueEntry *
GNUNET_DATASTORE_put (struct GNUNET_DATASTORE_Handle *h,
+ int rid,
const GNUNET_HashCode * key,
uint32_t size,
const void *data,
- uint32_t type,
+ enum GNUNET_BLOCK_Type type,
uint32_t priority,
uint32_t anonymity,
- struct GNUNET_TIME_Absolute expiration)
+ struct GNUNET_TIME_Absolute expiration,
+ unsigned int queue_priority,
+ unsigned int max_queue_size,
+ struct GNUNET_TIME_Relative timeout,
+ GNUNET_DATASTORE_ContinuationWithStatus cont,
+ void *cont_cls)
{
+ struct GNUNET_DATASTORE_QueueEntry *qe;
+ struct DataMessage *dm;
+ size_t msize;
+ union QueueContext qc;
+
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Asked to put %u bytes of data under key `%s'\n",
+ size,
+ GNUNET_h2s (key));
+#endif
+ msize = sizeof(struct DataMessage) + size;
+ GNUNET_assert (msize < GNUNET_SERVER_MAX_MESSAGE_SIZE);
+ qc.sc.cont = cont;
+ qc.sc.cont_cls = cont_cls;
+ qe = make_queue_entry (h, msize,
+ queue_priority, max_queue_size, timeout,
+ &process_status_message, &qc);
+ if (qe == NULL)
+ return NULL;
+ dm = (struct DataMessage* ) &qe[1];
+ dm->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_PUT);
+ dm->header.size = htons(msize);
+ dm->rid = htonl(rid);
+ dm->size = htonl(size);
+ dm->type = htonl(type);
+ dm->priority = htonl(priority);
+ dm->anonymity = htonl(anonymity);
+ dm->uid = GNUNET_htonll(0);
+ dm->expiration = GNUNET_TIME_absolute_hton(expiration);
+ dm->key = *key;
+ memcpy (&dm[1], data, size);
+ process_queue (h);
+ return qe;
+}
+
+
+/**
+ * Reserve space in the datastore. This function should be used
+ * to avoid "out of space" failures during a longer sequence of "put"
+ * operations (for example, when a file is being inserted).
+ *
+ * @param h handle to the datastore
+ * @param amount how much space (in bytes) should be reserved (for content only)
+ * @param entries how many entries will be created (to calculate per-entry overhead)
+ * @param queue_priority ranking of this request in the priority queue
+ * @param max_queue_size at what queue size should this request be dropped
+ * (if other requests of higher priority are in the queue)
+ * @param timeout how long to wait at most for a response (or before dying in queue)
+ * @param cont continuation to call when done; "success" will be set to
+ * a positive reservation value if space could be reserved.
+ * @param cont_cls closure for cont
+ * @return NULL if the entry was not queued, otherwise a handle that can be used to
+ * cancel; note that even if NULL is returned, the callback will be invoked
+ * (or rather, will already have been invoked)
+ */
+struct GNUNET_DATASTORE_QueueEntry *
+GNUNET_DATASTORE_reserve (struct GNUNET_DATASTORE_Handle *h,
+ uint64_t amount,
+ uint32_t entries,
+ unsigned int queue_priority,
+ unsigned int max_queue_size,
+ struct GNUNET_TIME_Relative timeout,
+ GNUNET_DATASTORE_ContinuationWithStatus cont,
+ void *cont_cls)
+{
+ struct GNUNET_DATASTORE_QueueEntry *qe;
+ struct ReserveMessage *rm;
+ union QueueContext qc;
+
+ if (cont == NULL)
+ cont = &drop_status_cont;
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Asked to reserve %llu bytes of data and %u entries'\n",
+ (unsigned long long) amount,
+ (unsigned int) entries);
+#endif
+ qc.sc.cont = cont;
+ qc.sc.cont_cls = cont_cls;
+ qe = make_queue_entry (h, sizeof(struct ReserveMessage),
+ queue_priority, max_queue_size, timeout,
+ &process_status_message, &qc);
+ if (qe == NULL)
+ return NULL;
+ rm = (struct ReserveMessage*) &qe[1];
+ rm->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_RESERVE);
+ rm->header.size = htons(sizeof (struct ReserveMessage));
+ rm->entries = htonl(entries);
+ rm->amount = GNUNET_htonll(amount);
+ process_queue (h);
+ return qe;
+}
+
+
+/**
+ * Signal that all of the data for which a reservation was made has
+ * been stored and that whatever excess space might have been reserved
+ * can now be released.
+ *
+ * @param h handle to the datastore
+ * @param rid reservation ID (value of "success" in original continuation
+ * from the "reserve" function).
+ * @param queue_priority ranking of this request in the priority queue
+ * @param max_queue_size at what queue size should this request be dropped
+ * (if other requests of higher priority are in the queue)
+ * @param queue_priority ranking of this request in the priority queue
+ * @param max_queue_size at what queue size should this request be dropped
+ * (if other requests of higher priority are in the queue)
+ * @param timeout how long to wait at most for a response
+ * @param cont continuation to call when done
+ * @param cont_cls closure for cont
+ * @return NULL if the entry was not queued, otherwise a handle that can be used to
+ * cancel; note that even if NULL is returned, the callback will be invoked
+ * (or rather, will already have been invoked)
+ */
+struct GNUNET_DATASTORE_QueueEntry *
+GNUNET_DATASTORE_release_reserve (struct GNUNET_DATASTORE_Handle *h,
+ int rid,
+ unsigned int queue_priority,
+ unsigned int max_queue_size,
+ struct GNUNET_TIME_Relative timeout,
+ GNUNET_DATASTORE_ContinuationWithStatus cont,
+ void *cont_cls)
+{
+ struct GNUNET_DATASTORE_QueueEntry *qe;
+ struct ReleaseReserveMessage *rrm;
+ union QueueContext qc;
+
+ if (cont == NULL)
+ cont = &drop_status_cont;
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Asked to release reserve %d\n",
+ rid);
+#endif
+ qc.sc.cont = cont;
+ qc.sc.cont_cls = cont_cls;
+ qe = make_queue_entry (h, sizeof(struct ReleaseReserveMessage),
+ queue_priority, max_queue_size, timeout,
+ &process_status_message, &qc);
+ if (qe == NULL)
+ return NULL;
+ rrm = (struct ReleaseReserveMessage*) &qe[1];
+ rrm->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_RELEASE_RESERVE);
+ rrm->header.size = htons(sizeof (struct ReleaseReserveMessage));
+ rrm->rid = htonl(rid);
+ process_queue (h);
+ return qe;
+}
+
+
+/**
+ * Update a value in the datastore.
+ *
+ * @param h handle to the datastore
+ * @param uid identifier for the value
+ * @param priority how much to increase the priority of the value
+ * @param expiration new expiration value should be MAX of existing and this argument
+ * @param queue_priority ranking of this request in the priority queue
+ * @param max_queue_size at what queue size should this request be dropped
+ * (if other requests of higher priority are in the queue)
+ * @param timeout how long to wait at most for a response
+ * @param cont continuation to call when done
+ * @param cont_cls closure for cont
+ * @return NULL if the entry was not queued, otherwise a handle that can be used to
+ * cancel; note that even if NULL is returned, the callback will be invoked
+ * (or rather, will already have been invoked)
+ */
+struct GNUNET_DATASTORE_QueueEntry *
+GNUNET_DATASTORE_update (struct GNUNET_DATASTORE_Handle *h,
+ unsigned long long uid,
+ uint32_t priority,
+ struct GNUNET_TIME_Absolute expiration,
+ unsigned int queue_priority,
+ unsigned int max_queue_size,
+ struct GNUNET_TIME_Relative timeout,
+ GNUNET_DATASTORE_ContinuationWithStatus cont,
+ void *cont_cls)
+{
+ struct GNUNET_DATASTORE_QueueEntry *qe;
+ struct UpdateMessage *um;
+ union QueueContext qc;
+
+ if (cont == NULL)
+ cont = &drop_status_cont;
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Asked to update entry %llu raising priority by %u and expiration to %llu\n",
+ uid,
+ (unsigned int) priority,
+ (unsigned long long) expiration.value);
+#endif
+ qc.sc.cont = cont;
+ qc.sc.cont_cls = cont_cls;
+ qe = make_queue_entry (h, sizeof(struct UpdateMessage),
+ queue_priority, max_queue_size, timeout,
+ &process_status_message, &qc);
+ if (qe == NULL)
+ return NULL;
+ um = (struct UpdateMessage*) &qe[1];
+ um->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_UPDATE);
+ um->header.size = htons(sizeof (struct UpdateMessage));
+ um->priority = htonl(priority);
+ um->expiration = GNUNET_TIME_absolute_hton(expiration);
+ um->uid = GNUNET_htonll(uid);
+ process_queue (h);
+ return qe;
}
+/**
+ * Explicitly remove some content from the database.
+ * The "cont"inuation will be called with status
+ * "GNUNET_OK" if content was removed, "GNUNET_NO"
+ * if no matching entry was found and "GNUNET_SYSERR"
+ * on all other types of errors.
+ *
+ * @param h handle to the datastore
+ * @param key key for the value
+ * @param size number of bytes in data
+ * @param data content stored
+ * @param queue_priority ranking of this request in the priority queue
+ * @param max_queue_size at what queue size should this request be dropped
+ * (if other requests of higher priority are in the queue)
+ * @param timeout how long to wait at most for a response
+ * @param cont continuation to call when done
+ * @param cont_cls closure for cont
+ * @return NULL if the entry was not queued, otherwise a handle that can be used to
+ * cancel; note that even if NULL is returned, the callback will be invoked
+ * (or rather, will already have been invoked)
+ */
+struct GNUNET_DATASTORE_QueueEntry *
+GNUNET_DATASTORE_remove (struct GNUNET_DATASTORE_Handle *h,
+ const GNUNET_HashCode *key,
+ uint32_t size,
+ const void *data,
+ unsigned int queue_priority,
+ unsigned int max_queue_size,
+ struct GNUNET_TIME_Relative timeout,
+ GNUNET_DATASTORE_ContinuationWithStatus cont,
+ void *cont_cls)
+{
+ struct GNUNET_DATASTORE_QueueEntry *qe;
+ struct DataMessage *dm;
+ size_t msize;
+ union QueueContext qc;
+
+ if (cont == NULL)
+ cont = &drop_status_cont;
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Asked to remove %u bytes under key `%s'\n",
+ size,
+ GNUNET_h2s (key));
+#endif
+ qc.sc.cont = cont;
+ qc.sc.cont_cls = cont_cls;
+ msize = sizeof(struct DataMessage) + size;
+ GNUNET_assert (msize < GNUNET_SERVER_MAX_MESSAGE_SIZE);
+ qe = make_queue_entry (h, msize,
+ queue_priority, max_queue_size, timeout,
+ &process_status_message, &qc);
+ if (qe == NULL)
+ return NULL;
+ dm = (struct DataMessage*) &qe[1];
+ dm->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_REMOVE);
+ dm->header.size = htons(msize);
+ dm->rid = htonl(0);
+ dm->size = htonl(size);
+ dm->type = htonl(0);
+ dm->priority = htonl(0);
+ dm->anonymity = htonl(0);
+ dm->uid = GNUNET_htonll(0);
+ dm->expiration = GNUNET_TIME_absolute_hton(GNUNET_TIME_UNIT_ZERO_ABS);
+ dm->key = *key;
+ memcpy (&dm[1], data, size);
+ process_queue (h);
+ return qe;
+}
+
+
+/**
+ * Type of a function to call when we receive a message
+ * from the service.
+ *
+ * @param cls closure
+ * @param msg message received, NULL on timeout or fatal error
+ */
+static void
+process_result_message (void *cls,
+ const struct GNUNET_MessageHeader * msg)
+{
+ struct GNUNET_DATASTORE_QueueEntry *qe = cls;
+ struct GNUNET_DATASTORE_Handle *h = qe->h;
+ struct ResultContext rc = qe->qc.rc;
+ const struct DataMessage *dm;
+ int was_transmitted;
+
+ h->in_receive = GNUNET_NO;
+ if (msg == NULL)
+ {
+ was_transmitted = qe->was_transmitted;
+ free_queue_entry (qe);
+ if (was_transmitted == GNUNET_YES)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+ _("Failed to receive response from database.\n"));
+ do_disconnect (h);
+ }
+ if (rc.iter != NULL)
+ rc.iter (rc.iter_cls,
+ NULL, 0, NULL, 0, 0, 0,
+ GNUNET_TIME_UNIT_ZERO_ABS, 0);
+ return;
+ }
+ GNUNET_assert (GNUNET_YES == qe->was_transmitted);
+ GNUNET_assert (h->queue_head == qe);
+ if (ntohs(msg->type) == GNUNET_MESSAGE_TYPE_DATASTORE_DATA_END)
+ {
+ GNUNET_break (ntohs(msg->size) == sizeof(struct GNUNET_MessageHeader));
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Received end of result set\n");
+#endif
+ free_queue_entry (qe);
+ if (rc.iter != NULL)
+ rc.iter (rc.iter_cls,
+ NULL, 0, NULL, 0, 0, 0,
+ GNUNET_TIME_UNIT_ZERO_ABS, 0);
+ process_queue (h);
+ return;
+ }
+ if ( (ntohs(msg->size) < sizeof(struct DataMessage)) ||
+ (ntohs(msg->type) != GNUNET_MESSAGE_TYPE_DATASTORE_DATA) ||
+ (ntohs(msg->size) != sizeof(struct DataMessage) + ntohl (((const struct DataMessage*)msg)->size)) )
+ {
+ GNUNET_break (0);
+ free_queue_entry (qe);
+ h->retry_time = GNUNET_TIME_UNIT_ZERO;
+ do_disconnect (h);
+ if (rc.iter != NULL)
+ rc.iter (rc.iter_cls,
+ NULL, 0, NULL, 0, 0, 0,
+ GNUNET_TIME_UNIT_ZERO_ABS, 0);
+ return;
+ }
+ if (rc.iter == NULL)
+ {
+ /* abort iteration */
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Aborting iteration via disconnect (client has cancelled)\n");
+#endif
+ free_queue_entry (qe);
+ h->retry_time = GNUNET_TIME_UNIT_ZERO;
+ do_disconnect (h);
+ return;
+ }
+ dm = (const struct DataMessage*) msg;
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Received result %llu with type %u and size %u with key %s\n",
+ (unsigned long long) GNUNET_ntohll(dm->uid),
+ ntohl(dm->type),
+ ntohl(dm->size),
+ GNUNET_h2s(&dm->key));
+#endif
+ rc.iter (rc.iter_cls,
+ &dm->key,
+ ntohl(dm->size),
+ &dm[1],
+ ntohl(dm->type),
+ ntohl(dm->priority),
+ ntohl(dm->anonymity),
+ GNUNET_TIME_absolute_ntoh(dm->expiration),
+ GNUNET_ntohll(dm->uid));
+}
+
+
+/**
+ * Get a random value from the datastore.
+ *
+ * @param h handle to the datastore
+ * @param queue_priority ranking of this request in the priority queue
+ * @param max_queue_size at what queue size should this request be dropped
+ * (if other requests of higher priority are in the queue)
+ * @param timeout how long to wait at most for a response
+ * @param iter function to call on a random value; it
+ * will be called once with a value (if available)
+ * and always once with a value of NULL.
+ * @param iter_cls closure for iter
+ * @return NULL if the entry was not queued, otherwise a handle that can be used to
+ * cancel; note that even if NULL is returned, the callback will be invoked
+ * (or rather, will already have been invoked)
+ */
+struct GNUNET_DATASTORE_QueueEntry *
+GNUNET_DATASTORE_get_random (struct GNUNET_DATASTORE_Handle *h,
+ unsigned int queue_priority,
+ unsigned int max_queue_size,
+ struct GNUNET_TIME_Relative timeout,
+ GNUNET_DATASTORE_Iterator iter,
+ void *iter_cls)
+{
+ struct GNUNET_DATASTORE_QueueEntry *qe;
+ struct GNUNET_MessageHeader *m;
+ union QueueContext qc;
+
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Asked to get random entry in %llu ms\n",
+ (unsigned long long) timeout.value);
+#endif
+ qc.rc.iter = iter;
+ qc.rc.iter_cls = iter_cls;
+ qe = make_queue_entry (h, sizeof(struct GNUNET_MessageHeader),
+ queue_priority, max_queue_size, timeout,
+ &process_result_message, &qc);
+ if (qe == NULL)
+ return NULL;
+ m = (struct GNUNET_MessageHeader*) &qe[1];
+ m->type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_GET_RANDOM);
+ m->size = htons(sizeof (struct GNUNET_MessageHeader));
+ process_queue (h);
+ return qe;
+}
+
+
+
/**
* Iterate over the results for a particular key
- * in the datastore.
+ * in the datastore. The iterator will only be called
+ * once initially; if the first call did contain a
+ * result, further results can be obtained by calling
+ * "GNUNET_DATASTORE_get_next" with the given argument.
*
* @param h handle to the datastore
* @param key maybe NULL (to match all entries)
* @param type desired type, 0 for any
+ * @param queue_priority ranking of this request in the priority queue
+ * @param max_queue_size at what queue size should this request be dropped
+ * (if other requests of higher priority are in the queue)
+ * @param timeout how long to wait at most for a response
* @param iter function to call on each matching value;
* will be called once with a NULL value at the end
* @param iter_cls closure for iter
+ * @return NULL if the entry was not queued, otherwise a handle that can be used to
+ * cancel; note that even if NULL is returned, the callback will be invoked
+ * (or rather, will already have been invoked)
*/
-void
+struct GNUNET_DATASTORE_QueueEntry *
GNUNET_DATASTORE_get (struct GNUNET_DATASTORE_Handle *h,
const GNUNET_HashCode * key,
- uint32_t type,
- GNUNET_DATASTORE_Iterator iter, void *iter_cls)
+ enum GNUNET_BLOCK_Type type,
+ unsigned int queue_priority,
+ unsigned int max_queue_size,
+ struct GNUNET_TIME_Relative timeout,
+ GNUNET_DATASTORE_Iterator iter,
+ void *iter_cls)
{
+ struct GNUNET_DATASTORE_QueueEntry *qe;
+ struct GetMessage *gm;
+ union QueueContext qc;
+
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Asked to look for data of type %u under key `%s'\n",
+ (unsigned int) type,
+ GNUNET_h2s (key));
+#endif
+ qc.rc.iter = iter;
+ qc.rc.iter_cls = iter_cls;
+ qe = make_queue_entry (h, sizeof(struct GetMessage),
+ queue_priority, max_queue_size, timeout,
+ &process_result_message, &qc);
+ if (qe == NULL)
+ return NULL;
+ gm = (struct GetMessage*) &qe[1];
+ gm->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_GET);
+ gm->type = htonl(type);
+ if (key != NULL)
+ {
+ gm->header.size = htons(sizeof (struct GetMessage));
+ gm->key = *key;
+ }
+ else
+ {
+ gm->header.size = htons(sizeof (struct GetMessage) - sizeof(GNUNET_HashCode));
+ }
+ process_queue (h);
+ return qe;
}
/**
- * Get a random value from the datastore.
- *
+ * Function called to trigger obtaining the next result
+ * from the datastore.
+ *
* @param h handle to the datastore
- * @param iter function to call on each matching value;
- * will be called exactly once; if no values
- * are available, the value will be NULL.
- * @param iter_cls closure for iter
+ * @param more GNUNET_YES to get moxre results, GNUNET_NO to abort
+ * iteration (with a final call to "iter" with key/data == NULL).
*/
-void
-GNUNET_DATASTORE_get_random (struct GNUNET_DATASTORE_Handle *h,
- GNUNET_DATASTORE_Iterator iter, void *iter_cls)
+void
+GNUNET_DATASTORE_get_next (struct GNUNET_DATASTORE_Handle *h,
+ int more)
{
+ struct GNUNET_DATASTORE_QueueEntry *qe = h->queue_head;
+ struct ResultContext rc = qe->qc.rc;
+
+ GNUNET_assert (&process_result_message == qe->response_proc);
+ if (GNUNET_YES == more)
+ {
+ h->in_receive = GNUNET_YES;
+ GNUNET_CLIENT_receive (h->client,
+ qe->response_proc,
+ qe,
+ GNUNET_TIME_absolute_get_remaining (qe->timeout));
+ return;
+ }
+ free_queue_entry (qe);
+ h->retry_time = GNUNET_TIME_UNIT_ZERO;
+ do_disconnect (h);
+ rc.iter (rc.iter_cls,
+ NULL, 0, NULL, 0, 0, 0,
+ GNUNET_TIME_UNIT_ZERO_ABS, 0);
}
/**
- * Explicitly remove some content from the database.
- *
- * @param h handle to the datastore
- * @param key key for the value
- * @param size number of bytes in data
- * @param data content stored
+ * Cancel a datastore operation. The final callback from the
+ * operation must not have been done yet.
+ *
+ * @param qe operation to cancel
*/
void
-GNUNET_DATASTORE_remove (struct GNUNET_DATASTORE_Handle *h,
- const GNUNET_HashCode * key,
- uint32_t size, const void *data)
+GNUNET_DATASTORE_cancel (struct GNUNET_DATASTORE_QueueEntry *qe)
{
+ struct GNUNET_DATASTORE_Handle *h;
+ int reconnect;
+
+ h = qe->h;
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Pending DATASTORE request %p cancelled (%d, %d)\n",
+ qe,
+ qe->was_transmitted,
+ h->queue_head == qe);
+#endif
+ reconnect = GNUNET_NO;
+ if (GNUNET_YES == qe->was_transmitted)
+ {
+ if (qe->response_proc == &process_result_message)
+ {
+ qe->qc.rc.iter = NULL;
+ if (GNUNET_YES != h->in_receive)
+ GNUNET_DATASTORE_get_next (h, GNUNET_YES);
+ return;
+ }
+ reconnect = GNUNET_YES;
+ }
+ free_queue_entry (qe);
+ if (reconnect)
+ {
+ h->retry_time = GNUNET_TIME_UNIT_ZERO;
+ do_disconnect (h);
+ }
+ else
+ {
+ process_queue (h);
+ }
}