/*
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, 2011 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 "gnunet_statistics_service.h"
#include "datastore.h"
/**
- * Handle to the datastore service.
+ * If a client stopped asking for more results, how many more do
+ * we receive from the DB before killing the connection? Trade-off
+ * between re-doing TCP handshakes and (needlessly) receiving
+ * useless results.
+ */
+#define MAX_EXCESS_RESULTS 8
+
+/**
+ * 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
+{
+ /**
+ * Function to call with the result.
+ */
+ GNUNET_DATASTORE_DatumProcessor proc;
+
+ /**
+ * Closure for proc.
+ */
+ void *proc_cls;
+
+};
+
+
+/**
+ * Context for a queue operation.
+ */
+union QueueContext
+{
+
+ struct StatusContext sc;
+
+ struct ResultContext rc;
+
+};
+
+
+
+/**
+ * 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.
+ */
+ int was_transmitted;
+
+};
+
+/**
+ * Handle to the datastore service.
*/
struct GNUNET_DATASTORE_Handle
{
+
+ /**
+ * Our configuration.
+ */
+ const struct GNUNET_CONFIGURATION_Handle *cfg;
+
+ /**
+ * Current connection to the datastore service.
+ */
+ struct GNUNET_CLIENT_Connection *client;
+
+ /**
+ * Handle for statistics.
+ */
+ struct GNUNET_STATISTICS_Handle *stats;
+
+ /**
+ * 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;
+
+ /**
+ * Number of results we're receiving for the current query
+ * after application stopped to care. Used to determine when
+ * to reset the connection.
+ */
+ unsigned int result_count;
+
+ /**
+ * Are we currently trying to receive from the service?
+ */
+ int in_receive;
+
+ /**
+ * We should ignore the next message(s) from the service.
+ */
+ unsigned int skip_next_messages;
+
};
+
/**
* Connect to the datastore service.
*
* @param cfg configuration to use
- * @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)
{
- return NULL;
+ struct GNUNET_CLIENT_Connection *c;
+ struct GNUNET_DATASTORE_Handle *h;
+
+ c = GNUNET_CLIENT_connect ("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->stats = GNUNET_STATISTICS_create ("datastore-api", cfg);
+ 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)
+{
+ 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);
}
* @param h handle to the datastore
* @param drop set to GNUNET_YES to delete all data in datastore (!)
*/
-void GNUNET_DATASTORE_disconnect (struct GNUNET_DATASTORE_Handle *h,
- int drop)
+void
+GNUNET_DATASTORE_disconnect (struct GNUNET_DATASTORE_Handle *h, int drop)
+{
+ struct GNUNET_DATASTORE_QueueEntry *qe;
+
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Datastore disconnect\n");
+#endif
+ if (NULL != h->th)
+ {
+ GNUNET_CLIENT_notify_transmit_ready_cancel (h->th);
+ h->th = NULL;
+ }
+ 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->reconnect_task);
+ h->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
+ }
+ while (NULL != (qe = h->queue_head))
+ {
+ GNUNET_assert (NULL != qe->response_proc);
+ qe->response_proc (h, NULL);
+ }
+ if (GNUNET_YES == drop)
+ {
+ h->client = GNUNET_CLIENT_connect ("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);
+ h->client = NULL;
+ }
+ GNUNET_break (0);
+ }
+ GNUNET_STATISTICS_destroy (h->stats, GNUNET_NO);
+ h->stats = NULL;
+ GNUNET_free (h);
+}
+
+
+/**
+ * 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;
+
+ GNUNET_STATISTICS_update (qe->h->stats,
+ gettext_noop ("# queue entry timeouts"), 1,
+ GNUNET_NO);
+ qe->task = GNUNET_SCHEDULER_NO_TASK;
+ GNUNET_assert (qe->was_transmitted == GNUNET_NO);
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Timeout of request in datastore queue\n");
+#endif
+ qe->response_proc (qe->h, 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
+ * @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
+ */
+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)
+{
+ 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;
+ }
+ if (c >= max_queue_size)
+ {
+ GNUNET_STATISTICS_update (h->stats, gettext_noop ("# queue overflows"), 1,
+ GNUNET_NO);
+ return NULL;
+ }
+ 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_STATISTICS_update (h->stats, gettext_noop ("# queue entries created"),
+ 1, GNUNET_NO);
+ GNUNET_CONTAINER_DLL_insert_after (h->queue_head, h->queue_tail, pos, ret);
+ h->queue_size++;
+ ret->task = GNUNET_SCHEDULER_add_delayed (timeout, &timeout_queue_entry, ret);
+ pos = ret->next;
+ while (pos != NULL)
+ {
+ if ((pos->max_queue < h->queue_size) && (pos->was_transmitted == GNUNET_NO))
+ {
+ GNUNET_assert (pos->response_proc != NULL);
+ /* move 'pos' element to head so that it will be
+ * killed on 'NULL' call below */
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Dropping request from datastore queue\n");
+#endif
+ GNUNET_CONTAINER_DLL_remove (h->queue_head, h->queue_tail, pos);
+ GNUNET_CONTAINER_DLL_insert (h->queue_head, h->queue_tail, pos);
+ GNUNET_STATISTICS_update (h->stats,
+ gettext_noop
+ ("# Requests dropped from datastore queue"), 1,
+ GNUNET_NO);
+ GNUNET_assert (h->queue_head == pos);
+ pos->response_proc (h, 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.rel_value < GNUNET_CONSTANTS_SERVICE_RETRY.rel_value)
+ h->retry_time = GNUNET_CONSTANTS_SERVICE_RETRY;
+ else
+ h->retry_time = GNUNET_TIME_relative_multiply (h->retry_time, 2);
+ if (h->retry_time.rel_value > GNUNET_CONSTANTS_SERVICE_TIMEOUT.rel_value)
+ h->retry_time = GNUNET_CONSTANTS_SERVICE_TIMEOUT;
+ h->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
+ h->client = GNUNET_CLIENT_connect ("datastore", h->cfg);
+ if (h->client == NULL)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "DATASTORE reconnect failed (fatally)\n");
+ return;
+ }
+ GNUNET_STATISTICS_update (h->stats,
+ gettext_noop
+ ("# datastore connections (re)created"), 1,
+ GNUNET_NO);
+#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->skip_next_messages = 0;
+ h->client = NULL;
+ h->reconnect_task =
+ GNUNET_SCHEDULER_add_delayed (h->retry_time, &try_reconnect, h);
+}
+
+
+/**
+ * Function called whenever we receive a message from
+ * the service. Calls the appropriate handler.
+ *
+ * @param cls the 'struct GNUNET_DATASTORE_Handle'
+ * @param msg the received message
+ */
+static void
+receive_cb (void *cls, const struct GNUNET_MessageHeader *msg)
{
+ struct GNUNET_DATASTORE_Handle *h = cls;
+ struct GNUNET_DATASTORE_QueueEntry *qe;
+
+ h->in_receive = GNUNET_NO;
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Receiving reply from datastore\n");
+#endif
+ if (h->skip_next_messages > 0)
+ {
+ h->skip_next_messages--;
+ process_queue (h);
+ return;
+ }
+ if (NULL == (qe = h->queue_head))
+ {
+ GNUNET_break (0);
+ process_queue (h);
+ return;
+ }
+ qe->response_proc (h, msg);
}
/**
- * Get the current on-disk size of the datastore.
+ * 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"));
+ GNUNET_STATISTICS_update (h->stats,
+ gettext_noop ("# transmission request failures"),
+ 1, GNUNET_NO);
+ 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 (qe->task);
+ qe->task = GNUNET_SCHEDULER_NO_TASK;
+ GNUNET_assert (GNUNET_NO == h->in_receive);
+ h->in_receive = GNUNET_YES;
+ GNUNET_CLIENT_receive (h->client, &receive_cb, h,
+ GNUNET_TIME_absolute_get_remaining (qe->timeout));
+ GNUNET_STATISTICS_update (h->stats,
+ gettext_noop ("# bytes sent to datastore"), 1,
+ GNUNET_NO);
+ return msize;
+}
+
+
+/**
+ * Process entries in the queue (or do nothing if we are already
+ * doing so).
+ *
* @param h handle to the datastore
- * @return size estimate, -1 if datastore is not available (yet)
*/
-unsigned long long GNUNET_DATASTORE_size (struct GNUNET_DATASTORE_Handle *h)
+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 (GNUNET_YES == h->in_receive)
+ {
+ /* wait for response to previous query */
+ return;
+ }
+#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);
+ GNUNET_assert (GNUNET_NO == h->in_receive);
+ GNUNET_break (NULL != h->th);
+}
+
+
+/**
+ * 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, int32_t result, const char *emsg)
{
- return 0;
+ /* do nothing */
+}
+
+
+/**
+ * Free a queue entry. Removes the given entry from the
+ * queue and releases associated resources. Does NOT
+ * call the callback.
+ *
+ * @param qe entry to free.
+ */
+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 (qe->task);
+ qe->task = GNUNET_SCHEDULER_NO_TASK;
+ }
+ h->queue_size--;
+ qe->was_transmitted = GNUNET_SYSERR; /* use-after-free warning */
+ 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_Handle *h = cls;
+ struct GNUNET_DATASTORE_QueueEntry *qe;
+ struct StatusContext rc;
+ const struct StatusMessage *sm;
+ const char *emsg;
+ int32_t status;
+ int was_transmitted;
+
+ if (NULL == (qe = h->queue_head))
+ {
+ GNUNET_break (0);
+ do_disconnect (h);
+ return;
+ }
+ rc = qe->qc.sc;
+ if (msg == NULL)
+ {
+ was_transmitted = qe->was_transmitted;
+ free_queue_entry (qe);
+ if (was_transmitted == GNUNET_YES)
+ do_disconnect (h);
+ else
+ process_queue (h);
+ if (rc.cont != NULL)
+ rc.cont (rc.cont_cls, GNUNET_SYSERR,
+ _("Failed to receive status response from database."));
+ return;
+ }
+ GNUNET_assert (GNUNET_YES == qe->was_transmitted);
+ 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);
+ if (rc.cont != NULL)
+ 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
+ GNUNET_STATISTICS_update (h->stats,
+ gettext_noop ("# status messages received"), 1,
+ GNUNET_NO);
+ h->retry_time.rel_value = 0;
+ process_queue (h);
+ if (rc.cont != NULL)
+ rc.cont (rc.cont_cls, status, emsg);
}
* 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 type type of the content
* @param priority priority of the content
* @param anonymity anonymity-level for the content
+ * @param replication how often should the content be replicated to other peers?
* @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
-GNUNET_DATASTORE_put (struct GNUNET_DATASTORE_Handle *h,
- const GNUNET_HashCode * key,
- uint32_t size,
- const void *data,
- uint32_t type,
- uint32_t priority,
- uint32_t anonymity,
- struct GNUNET_TIME_Absolute expiration)
+struct GNUNET_DATASTORE_QueueEntry *
+GNUNET_DATASTORE_put (struct GNUNET_DATASTORE_Handle *h, uint32_t rid,
+ const GNUNET_HashCode * key, size_t size,
+ const void *data, enum GNUNET_BLOCK_Type type,
+ uint32_t priority, uint32_t anonymity,
+ uint32_t replication,
+ 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' for %llu ms\n",
+ size, GNUNET_h2s (key),
+ GNUNET_TIME_absolute_get_remaining (expiration).rel_value);
+#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)
+ {
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Could not create queue entry for PUT\n");
+#endif
+ return NULL;
+ }
+ GNUNET_STATISTICS_update (h->stats, gettext_noop ("# PUT requests executed"),
+ 1, GNUNET_NO);
+ 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 ((uint32_t) size);
+ dm->type = htonl (type);
+ dm->priority = htonl (priority);
+ dm->anonymity = htonl (anonymity);
+ dm->replication = htonl (replication);
+ dm->reserved = htonl (0);
+ 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;
}
/**
- * Iterate over the results for a particular key
- * in the datastore.
+ * 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 key maybe NULL (to match all entries)
- * @param type desired type, 0 for any
- * @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
+ * @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)
*/
-void
-GNUNET_DATASTORE_get (struct GNUNET_DATASTORE_Handle *h,
- const GNUNET_HashCode * key,
- uint32_t type,
- GNUNET_DATASTORE_Iterator iter, void *iter_cls)
+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)
+ {
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Could not create queue entry to reserve\n");
+#endif
+ return NULL;
+ }
+ GNUNET_STATISTICS_update (h->stats,
+ gettext_noop ("# RESERVE requests executed"), 1,
+ GNUNET_NO);
+ 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;
}
/**
- * Get a random value from the datastore.
+ * 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 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 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)
*/
-void
-GNUNET_DATASTORE_get_random (struct GNUNET_DATASTORE_Handle *h,
- GNUNET_DATASTORE_Iterator iter, void *iter_cls)
+struct GNUNET_DATASTORE_QueueEntry *
+GNUNET_DATASTORE_release_reserve (struct GNUNET_DATASTORE_Handle *h,
+ uint32_t 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)
+ {
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Could not create queue entry to release reserve\n");
+#endif
+ return NULL;
+ }
+ GNUNET_STATISTICS_update (h->stats,
+ gettext_noop
+ ("# RELEASE RESERVE requests executed"), 1,
+ GNUNET_NO);
+ 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, uint64_t 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.abs_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)
+ {
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Could not create queue entry for UPDATE\n");
+#endif
+ return NULL;
+ }
+ GNUNET_STATISTICS_update (h->stats,
+ gettext_noop ("# UPDATE requests executed"), 1,
+ GNUNET_NO);
+ 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)
*/
-void
+struct GNUNET_DATASTORE_QueueEntry *
GNUNET_DATASTORE_remove (struct GNUNET_DATASTORE_Handle *h,
- const GNUNET_HashCode * key,
- uint32_t size, const void *data)
+ const GNUNET_HashCode * key, size_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)
+ {
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Could not create queue entry for REMOVE\n");
+#endif
+ return NULL;
+ }
+ GNUNET_STATISTICS_update (h->stats,
+ gettext_noop ("# REMOVE requests executed"), 1,
+ GNUNET_NO);
+ 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_Handle *h = cls;
+ struct GNUNET_DATASTORE_QueueEntry *qe;
+ struct ResultContext rc;
+ const struct DataMessage *dm;
+ int was_transmitted;
+
+ if (msg == NULL)
+ {
+ qe = h->queue_head;
+ GNUNET_assert (NULL != qe);
+ rc = qe->qc.rc;
+ 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);
+ }
+ else
+ {
+ process_queue (h);
+ }
+ if (rc.proc != NULL)
+ rc.proc (rc.proc_cls, NULL, 0, NULL, 0, 0, 0, GNUNET_TIME_UNIT_ZERO_ABS,
+ 0);
+ return;
+ }
+ if (ntohs (msg->type) == GNUNET_MESSAGE_TYPE_DATASTORE_DATA_END)
+ {
+ GNUNET_break (ntohs (msg->size) == sizeof (struct GNUNET_MessageHeader));
+ qe = h->queue_head;
+ rc = qe->qc.rc;
+ GNUNET_assert (GNUNET_YES == qe->was_transmitted);
+ free_queue_entry (qe);
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Received end of result set, new queue size is %u\n",
+ h->queue_size);
+#endif
+ if (rc.proc != NULL)
+ rc.proc (rc.proc_cls, NULL, 0, NULL, 0, 0, 0, GNUNET_TIME_UNIT_ZERO_ABS,
+ 0);
+ h->retry_time.rel_value = 0;
+ h->result_count = 0;
+ process_queue (h);
+ return;
+ }
+ qe = h->queue_head;
+ GNUNET_assert (NULL != qe);
+ rc = qe->qc.rc;
+ if (GNUNET_YES != qe->was_transmitted)
+ {
+ GNUNET_break (0);
+ free_queue_entry (qe);
+ h->retry_time = GNUNET_TIME_UNIT_ZERO;
+ do_disconnect (h);
+ if (rc.proc != NULL)
+ rc.proc (rc.proc_cls, NULL, 0, NULL, 0, 0, 0, GNUNET_TIME_UNIT_ZERO_ABS,
+ 0);
+ 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.proc != NULL)
+ rc.proc (rc.proc_cls, NULL, 0, NULL, 0, 0, 0, GNUNET_TIME_UNIT_ZERO_ABS,
+ 0);
+ return;
+ }
+ GNUNET_STATISTICS_update (h->stats, gettext_noop ("# Results received"), 1,
+ GNUNET_NO);
+ 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
+ free_queue_entry (qe);
+ h->retry_time.rel_value = 0;
+ process_queue (h);
+ if (rc.proc != NULL)
+ rc.proc (rc.proc_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 for content replication.
+ * Returns a single, random value among those with the highest
+ * replication score, lowering positive replication scores by one for
+ * the chosen value (if only content with a replication score exists,
+ * a random value is returned and replication scores are not changed).
+ *
+ * @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 proc 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 proc_cls closure for proc
+ * @return NULL if the entry was not queued, otherwise a handle that can be used to
+ * cancel
+ */
+struct GNUNET_DATASTORE_QueueEntry *
+GNUNET_DATASTORE_get_for_replication (struct GNUNET_DATASTORE_Handle *h,
+ unsigned int queue_priority,
+ unsigned int max_queue_size,
+ struct GNUNET_TIME_Relative timeout,
+ GNUNET_DATASTORE_DatumProcessor proc,
+ void *proc_cls)
+{
+ struct GNUNET_DATASTORE_QueueEntry *qe;
+ struct GNUNET_MessageHeader *m;
+ union QueueContext qc;
+
+ GNUNET_assert (NULL != proc);
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Asked to get replication entry in %llu ms\n",
+ (unsigned long long) timeout.rel_value);
+#endif
+ qc.rc.proc = proc;
+ qc.rc.proc_cls = proc_cls;
+ qe = make_queue_entry (h, sizeof (struct GNUNET_MessageHeader),
+ queue_priority, max_queue_size, timeout,
+ &process_result_message, &qc);
+ if (qe == NULL)
+ {
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Could not create queue entry for GET REPLICATION\n");
+#endif
+ return NULL;
+ }
+ GNUNET_STATISTICS_update (h->stats,
+ gettext_noop
+ ("# GET REPLICATION requests executed"), 1,
+ GNUNET_NO);
+ m = (struct GNUNET_MessageHeader *) &qe[1];
+ m->type = htons (GNUNET_MESSAGE_TYPE_DATASTORE_GET_REPLICATION);
+ m->size = htons (sizeof (struct GNUNET_MessageHeader));
+ process_queue (h);
+ return qe;
+}
+
+
+/**
+ * Get a single zero-anonymity value from the datastore.
+ *
+ * @param h handle to the datastore
+ * @param offset offset of the result (modulo num-results); set to
+ * a random 64-bit value initially; then increment by
+ * one each time; detect that all results have been found by uid
+ * being again the first uid ever returned.
+ * @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 type allowed type for the operation (never zero)
+ * @param proc function to call on a random value; it
+ * will be called once with a value (if available)
+ * or with NULL if none value exists.
+ * @param proc_cls closure for proc
+ * @return NULL if the entry was not queued, otherwise a handle that can be used to
+ * cancel
+ */
+struct GNUNET_DATASTORE_QueueEntry *
+GNUNET_DATASTORE_get_zero_anonymity (struct GNUNET_DATASTORE_Handle *h,
+ uint64_t offset,
+ unsigned int queue_priority,
+ unsigned int max_queue_size,
+ struct GNUNET_TIME_Relative timeout,
+ enum GNUNET_BLOCK_Type type,
+ GNUNET_DATASTORE_DatumProcessor proc,
+ void *proc_cls)
{
+ struct GNUNET_DATASTORE_QueueEntry *qe;
+ struct GetZeroAnonymityMessage *m;
+ union QueueContext qc;
+
+ GNUNET_assert (NULL != proc);
+ GNUNET_assert (type != GNUNET_BLOCK_TYPE_ANY);
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Asked to get %llu-th zero-anonymity entry of type %d in %llu ms\n",
+ (unsigned long long) offset, type,
+ (unsigned long long) timeout.rel_value);
+#endif
+ qc.rc.proc = proc;
+ qc.rc.proc_cls = proc_cls;
+ qe = make_queue_entry (h, sizeof (struct GetZeroAnonymityMessage),
+ queue_priority, max_queue_size, timeout,
+ &process_result_message, &qc);
+ if (qe == NULL)
+ {
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Could not create queue entry for zero-anonymity procation\n");
+#endif
+ return NULL;
+ }
+ GNUNET_STATISTICS_update (h->stats,
+ gettext_noop
+ ("# GET ZERO ANONYMITY requests executed"), 1,
+ GNUNET_NO);
+ m = (struct GetZeroAnonymityMessage *) &qe[1];
+ m->header.type = htons (GNUNET_MESSAGE_TYPE_DATASTORE_GET_ZERO_ANONYMITY);
+ m->header.size = htons (sizeof (struct GetZeroAnonymityMessage));
+ m->type = htonl ((uint32_t) type);
+ m->offset = GNUNET_htonll (offset);
+ process_queue (h);
+ return qe;
+}
+
+
+/**
+ * Get a result for a particular key from the datastore. The processor
+ * will only be called once.
+ *
+ * @param h handle to the datastore
+ * @param offset offset of the result (modulo num-results); set to
+ * a random 64-bit value initially; then increment by
+ * one each time; detect that all results have been found by uid
+ * being again the first uid ever returned.
+ * @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 proc function to call on each matching value;
+ * will be called once with a NULL value at the end
+ * @param proc_cls closure for proc
+ * @return NULL if the entry was not queued, otherwise a handle that can be used to
+ * cancel
+ */
+struct GNUNET_DATASTORE_QueueEntry *
+GNUNET_DATASTORE_get_key (struct GNUNET_DATASTORE_Handle *h, uint64_t offset,
+ const GNUNET_HashCode * key,
+ enum GNUNET_BLOCK_Type type,
+ unsigned int queue_priority,
+ unsigned int max_queue_size,
+ struct GNUNET_TIME_Relative timeout,
+ GNUNET_DATASTORE_DatumProcessor proc, void *proc_cls)
+{
+ struct GNUNET_DATASTORE_QueueEntry *qe;
+ struct GetMessage *gm;
+ union QueueContext qc;
+
+ GNUNET_assert (NULL != proc);
+#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.proc = proc;
+ qc.rc.proc_cls = proc_cls;
+ qe = make_queue_entry (h, sizeof (struct GetMessage), queue_priority,
+ max_queue_size, timeout, &process_result_message, &qc);
+ if (qe == NULL)
+ {
+#if DEBUG_DATASTORE
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Could not queue request for `%s'\n",
+ GNUNET_h2s (key));
+#endif
+ return NULL;
+ }
+ GNUNET_STATISTICS_update (h->stats, gettext_noop ("# GET requests executed"),
+ 1, GNUNET_NO);
+ gm = (struct GetMessage *) &qe[1];
+ gm->header.type = htons (GNUNET_MESSAGE_TYPE_DATASTORE_GET);
+ gm->type = htonl (type);
+ gm->offset = GNUNET_htonll (offset);
+ 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;
+}
+
+
+/**
+ * Cancel a datastore operation. The final callback from the
+ * operation must not have been done yet.
+ *
+ * @param qe operation to cancel
+ */
+void
+GNUNET_DATASTORE_cancel (struct GNUNET_DATASTORE_QueueEntry *qe)
+{
+ struct GNUNET_DATASTORE_Handle *h;
+
+ GNUNET_assert (GNUNET_SYSERR != qe->was_transmitted);
+ 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
+ if (GNUNET_YES == qe->was_transmitted)
+ {
+ free_queue_entry (qe);
+ h->skip_next_messages++;
+ return;
+ }
+ free_queue_entry (qe);
+ process_queue (h);
}
projects / oweals / gnunet.git / blobdiff