/*
This file is part of GNUnet.
- (C) 2012, 2013 Christian Grothoff (and other contributing authors)
+ (C) 2012-2014 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
Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.
*/
-
/**
* @file set/set_api.c
* @brief api for the set service
* @author Florian Dold
+ * @author Christian Grothoff
*/
#include "platform.h"
#include "gnunet_util_lib.h"
struct GNUNET_CLIENT_Connection *client;
/**
- * Message queue for 'client'.
+ * Message queue for @e client.
*/
struct GNUNET_MQ_Handle *mq;
*/
struct GNUNET_SET_OperationHandle *ops_tail;
+ /**
+ * Callback for the current iteration over the set,
+ * NULL if no iterator is active.
+ */
+ GNUNET_SET_ElementIterator iterator;
+
+ /**
+ * Closure for @e iterator
+ */
+ void *iterator_cls;
+
/**
* Should the set be destroyed once all operations are gone?
*/
int invalid;
/**
- * Callback for the current iteration over the set,
- * NULL if no iterator is active.
- */
- GNUNET_SET_ElementIterator iterator;
-
- /**
- * Closure for 'iterator'
+ * Both client and service count the number of iterators
+ * created so far to match replies with iterators.
*/
- void *iterator_cls;
+ uint16_t iteration_id;
};
/**
- * Opaque handle to a set operation request from another peer.
+ * Handle for a set operation request from another peer.
*/
struct GNUNET_SET_Request
{
/**
* Has the request been accepted already?
- * GNUNET_YES/GNUNET_NO
+ * #GNUNET_YES/#GNUNET_NO
*/
int accepted;
};
/**
- * Handle to an operation.
- * Only known to the service after commiting
+ * Handle to an operation. Only known to the service after committing
* the handle with a set.
*/
struct GNUNET_SET_OperationHandle
GNUNET_SET_ResultIterator result_cb;
/**
- * Closure for result_cb.
+ * Closure for @e result_cb.
*/
void *result_cls;
*/
struct GNUNET_SET_Handle *set;
- /**
- * Request ID to identify the operation within the set.
- */
- uint32_t request_id;
-
/**
* Message sent to the server on calling conclude,
* NULL if conclude has been called.
* Handles are kept in a linked list.
*/
struct GNUNET_SET_OperationHandle *next;
+
+ /**
+ * Request ID to identify the operation within the set.
+ */
+ uint32_t request_id;
};
*/
struct GNUNET_MQ_Handle* mq;
+ /**
+ * Configuration handle for the listener, stored
+ * here to be able to reconnect transparently on
+ * connection failure.
+ */
+ const struct GNUNET_CONFIGURATION_Handle *cfg;
+
/**
* Function to call on a new incoming request,
* or on error.
GNUNET_SET_ListenCallback listen_cb;
/**
- * Closure for listen_cb.
+ * Closure for @e listen_cb.
*/
void *listen_cls;
+
+ /**
+ * Application ID we listen for.
+ */
+ struct GNUNET_HashCode app_id;
+
+ /**
+ * Time to wait until we try to reconnect on failure.
+ */
+ struct GNUNET_TIME_Relative reconnect_backoff;
+
+ /**
+ * Task for reconnecting when the listener fails.
+ */
+ GNUNET_SCHEDULER_TaskIdentifier reconnect_task;
+
+ /**
+ * Operation we listen for.
+ */
+ enum GNUNET_SET_OperationType operation;
};
/**
- * Handle element for iteration over the set.
+ * Handle element for iteration over the set. Notifies the
+ * iterator and sends an acknowledgement to the service.
*
- * @param cls the set
+ * @param cls the `struct GNUNET_SET_Handle *`
* @param mh the message
*/
static void
-handle_iter_element (void *cls, const struct GNUNET_MessageHeader *mh)
+handle_iter_element (void *cls,
+ const struct GNUNET_MessageHeader *mh)
{
struct GNUNET_SET_Handle *set = cls;
+ GNUNET_SET_ElementIterator iter = set->iterator;
struct GNUNET_SET_Element element;
- const struct GNUNET_SET_IterResponseMessage *msg =
- (const struct GNUNET_SET_IterResponseMessage *) mh;
-
- if (NULL == set->iterator)
- return;
+ const struct GNUNET_SET_IterResponseMessage *msg;
+ struct GNUNET_SET_IterAckMessage *ack_msg;
+ struct GNUNET_MQ_Envelope *ev;
+ uint16_t msize;
- element.type = htons (mh->type);
- element.data = &msg[1];
- set->iterator (set->iterator_cls, &element);
+ msize = ntohs (mh->size);
+ if (msize < sizeof (sizeof (struct GNUNET_SET_IterResponseMessage)))
+ {
+ /* message malformed */
+ GNUNET_break (0);
+ set->iterator = NULL;
+ set->iteration_id++;
+ iter (set->iterator_cls,
+ NULL);
+ iter = NULL;
+ }
+ msg = (const struct GNUNET_SET_IterResponseMessage *) mh;
+ if (set->iteration_id != ntohs (msg->iteration_id))
+ {
+ /* element from a previous iteration, skip! */
+ iter = NULL;
+ }
+ if (NULL != iter)
+ {
+ element.size = msize - sizeof (struct GNUNET_SET_IterResponseMessage);
+ element.element_type = htons (msg->element_type);
+ element.data = &msg[1];
+ iter (set->iterator_cls,
+ &element);
+ }
+ ev = GNUNET_MQ_msg (ack_msg,
+ GNUNET_MESSAGE_TYPE_SET_ITER_ACK);
+ ack_msg->send_more = htonl ((NULL != iter));
+ GNUNET_MQ_send (set->mq, ev);
}
/**
- * Handle element for iteration over the set.
+ * Handle message signalling conclusion of iteration over the set.
+ * Notifies the iterator that we are done.
*
* @param cls the set
* @param mh the message
*/
static void
-handle_iter_done (void *cls, const struct GNUNET_MessageHeader *mh)
+handle_iter_done (void *cls,
+ const struct GNUNET_MessageHeader *mh)
{
struct GNUNET_SET_Handle *set = cls;
+ GNUNET_SET_ElementIterator iter = set->iterator;
- if (NULL == set->iterator)
+ if (NULL == iter)
return;
-
- set->iterator (set->iterator_cls, NULL);
+ set->iterator = NULL;
+ set->iteration_id++;
+ iter (set->iterator_cls,
+ NULL);
}
* @param mh the message
*/
static void
-handle_result (void *cls, const struct GNUNET_MessageHeader *mh)
+handle_result (void *cls,
+ const struct GNUNET_MessageHeader *mh)
{
- const struct GNUNET_SET_ResultMessage *msg;
struct GNUNET_SET_Handle *set = cls;
+ const struct GNUNET_SET_ResultMessage *msg;
struct GNUNET_SET_OperationHandle *oh;
struct GNUNET_SET_Element e;
enum GNUNET_SET_Status result_status;
msg = (const struct GNUNET_SET_ResultMessage *) mh;
- GNUNET_assert (NULL != set);
GNUNET_assert (NULL != set->mq);
-
result_status = ntohs (msg->result_status);
-
- oh = GNUNET_MQ_assoc_get (set->mq, ntohl (msg->request_id));
- GNUNET_assert (NULL != oh);
- /* status is not STATUS_OK => there's no attached element,
- * and this is the last result message we get */
+ oh = GNUNET_MQ_assoc_get (set->mq,
+ ntohl (msg->request_id));
+ if (NULL == oh)
+ {
+ /* 'oh' can be NULL if we canceled the operation, but the service
+ did not get the cancel message yet. */
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Ignoring result from canceled operation\n");
+ return;
+ }
if (GNUNET_SET_STATUS_OK != result_status)
{
+ /* status is not #GNUNET_SET_STATUS_OK => there's no attached element,
+ * and this is the last result message we get */
GNUNET_MQ_assoc_remove (set->mq, ntohl (msg->request_id));
- GNUNET_CONTAINER_DLL_remove (oh->set->ops_head, oh->set->ops_tail, oh);
- if (GNUNET_YES == oh->set->destroy_requested)
- GNUNET_SET_destroy (oh->set);
+ GNUNET_CONTAINER_DLL_remove (set->ops_head,
+ set->ops_tail,
+ oh);
+ if ( (GNUNET_YES == set->destroy_requested) &&
+ (NULL == set->ops_head) )
+ GNUNET_SET_destroy (set);
if (NULL != oh->result_cb)
- oh->result_cb (oh->result_cls, NULL, result_status);
+ oh->result_cb (oh->result_cls,
+ NULL,
+ result_status);
GNUNET_free (oh);
return;
}
-
e.data = &msg[1];
e.size = ntohs (mh->size) - sizeof (struct GNUNET_SET_ResultMessage);
- e.type = msg->element_type;
+ e.element_type = msg->element_type;
if (NULL != oh->result_cb)
- oh->result_cb (oh->result_cls, &e, result_status);
+ oh->result_cb (oh->result_cls,
+ &e,
+ result_status);
}
+
/**
- * Handle request message for a listen operation
+ * Destroy the given set operation.
*
- * @param cls the listen handle
- * @param mh the message
+ * @param oh set operation to destroy
*/
static void
-handle_request (void *cls, const struct GNUNET_MessageHeader *mh)
+set_operation_destroy (struct GNUNET_SET_OperationHandle *oh)
{
- struct GNUNET_SET_RequestMessage *msg = (struct GNUNET_SET_RequestMessage *) mh;
- struct GNUNET_SET_ListenHandle *lh = cls;
- struct GNUNET_SET_Request *req;
- struct GNUNET_MessageHeader *context_msg;
-
- LOG (GNUNET_ERROR_TYPE_DEBUG, "processing operation request\n");
- req = GNUNET_new (struct GNUNET_SET_Request);
- req->accept_id = ntohl (msg->accept_id);
- context_msg = GNUNET_MQ_extract_nested_mh (msg);
- /* calling GNUNET_SET_accept in the listen cb will set req->accepted */
- lh->listen_cb (lh->listen_cls, &msg->peer_id, context_msg, req);
+ struct GNUNET_SET_Handle *set = oh->set;
+ struct GNUNET_SET_OperationHandle *h_assoc;
- if (GNUNET_NO == req->accepted)
+ if (NULL != oh->conclude_mqm)
+ GNUNET_MQ_discard (oh->conclude_mqm);
+ /* is the operation already commited? */
+ if (NULL != set)
{
- struct GNUNET_MQ_Envelope *mqm;
- struct GNUNET_SET_AcceptRejectMessage *amsg;
-
- mqm = GNUNET_MQ_msg (amsg, GNUNET_MESSAGE_TYPE_SET_REJECT);
- /* no request id, as we refused */
- amsg->request_id = htonl (0);
- amsg->accept_reject_id = msg->accept_id;
- GNUNET_MQ_send (lh->mq, mqm);
- GNUNET_free (req);
- LOG (GNUNET_ERROR_TYPE_DEBUG, "rejecting request\n");
+ GNUNET_CONTAINER_DLL_remove (set->ops_head,
+ set->ops_tail,
+ oh);
+ h_assoc = GNUNET_MQ_assoc_remove (set->mq,
+ oh->request_id);
+ GNUNET_assert ((NULL == h_assoc) || (h_assoc == oh));
}
-
- LOG (GNUNET_ERROR_TYPE_DEBUG, "processed op request from service\n");
-
- /* the accept-case is handled in GNUNET_SET_accept,
- * as we have the accept message available there */
+ GNUNET_free (oh);
}
-static void
-handle_client_listener_error (void *cls, enum GNUNET_MQ_Error error)
+/**
+ * Cancel the given set operation. We need to send an explicit cancel
+ * message, as all operations one one set communicate using one
+ * handle.
+ *
+ * @param oh set operation to cancel
+ */
+void
+GNUNET_SET_operation_cancel (struct GNUNET_SET_OperationHandle *oh)
{
- struct GNUNET_SET_ListenHandle *lh = cls;
+ struct GNUNET_SET_Handle *set = oh->set;
+ struct GNUNET_SET_CancelMessage *m;
+ struct GNUNET_MQ_Envelope *mqm;
- lh->listen_cb (lh->listen_cls, NULL, NULL, NULL);
+ if (NULL != set)
+ {
+ mqm = GNUNET_MQ_msg (m, GNUNET_MESSAGE_TYPE_SET_CANCEL);
+ m->request_id = htonl (oh->request_id);
+ GNUNET_MQ_send (set->mq, mqm);
+ }
+ set_operation_destroy (oh);
+ if ( (NULL != set) &&
+ (GNUNET_YES == set->destroy_requested) &&
+ (NULL == set->ops_head) )
+ {
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Destroying set after operation cancel\n");
+ GNUNET_SET_destroy (set);
+ }
}
+/**
+ * We encountered an error communicating with the set service while
+ * performing a set operation. Report to the application.
+ *
+ * @param cls the `struct GNUNET_SET_Handle`
+ * @param error error code
+ */
static void
-handle_client_set_error (void *cls, enum GNUNET_MQ_Error error)
+handle_client_set_error (void *cls,
+ enum GNUNET_MQ_Error error)
{
struct GNUNET_SET_Handle *set = cls;
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Handling client set error\n");
while (NULL != set->ops_head)
{
if (NULL != set->ops_head->result_cb)
- set->ops_head->result_cb (set->ops_head->result_cls, NULL,
+ set->ops_head->result_cb (set->ops_head->result_cls,
+ NULL,
GNUNET_SET_STATUS_FAILURE);
- GNUNET_SET_operation_cancel (set->ops_head);
+ set_operation_destroy (set->ops_head);
}
-
set->invalid = GNUNET_YES;
+ if (GNUNET_YES == set->destroy_requested)
+ {
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Destroying set after operation failure\n");
+ GNUNET_SET_destroy (set);
+ }
}
GNUNET_SET_create (const struct GNUNET_CONFIGURATION_Handle *cfg,
enum GNUNET_SET_OperationType op)
{
- struct GNUNET_SET_Handle *set;
- struct GNUNET_MQ_Envelope *mqm;
- struct GNUNET_SET_CreateMessage *msg;
static const struct GNUNET_MQ_MessageHandler mq_handlers[] = {
- {handle_result, GNUNET_MESSAGE_TYPE_SET_RESULT, 0},
- {handle_iter_element, GNUNET_MESSAGE_TYPE_SET_ITER_ELEMENT, 0},
- {handle_iter_done, GNUNET_MESSAGE_TYPE_SET_ITER_DONE, 0},
+ { &handle_result,
+ GNUNET_MESSAGE_TYPE_SET_RESULT,
+ 0 },
+ { &handle_iter_element,
+ GNUNET_MESSAGE_TYPE_SET_ITER_ELEMENT,
+ 0 },
+ { &handle_iter_done,
+ GNUNET_MESSAGE_TYPE_SET_ITER_DONE,
+ sizeof (struct GNUNET_MessageHeader) },
GNUNET_MQ_HANDLERS_END
};
+ struct GNUNET_SET_Handle *set;
+ struct GNUNET_MQ_Envelope *mqm;
+ struct GNUNET_SET_CreateMessage *msg;
set = GNUNET_new (struct GNUNET_SET_Handle);
set->client = GNUNET_CLIENT_connect ("set", cfg);
- LOG (GNUNET_ERROR_TYPE_DEBUG, "set client created\n");
- GNUNET_assert (NULL != set->client);
- set->mq = GNUNET_MQ_queue_for_connection_client (set->client, mq_handlers,
- handle_client_set_error, set);
+ if (NULL == set->client)
+ {
+ GNUNET_free (set);
+ return NULL;
+ }
+ set->mq = GNUNET_MQ_queue_for_connection_client (set->client,
+ mq_handlers,
+ &handle_client_set_error, set);
GNUNET_assert (NULL != set->mq);
- mqm = GNUNET_MQ_msg (msg, GNUNET_MESSAGE_TYPE_SET_CREATE);
- msg->operation = htons (op);
+ mqm = GNUNET_MQ_msg (msg,
+ GNUNET_MESSAGE_TYPE_SET_CREATE);
+ msg->operation = htonl (op);
GNUNET_MQ_send (set->mq, mqm);
return set;
}
/**
- * Add an element to the given set.
- * After the element has been added (in the sense of being
- * transmitted to the set service), cont will be called.
- * Calls to add_element can be queued
+ * Add an element to the given set. After the element has been added
+ * (in the sense of being transmitted to the set service), @a cont
+ * will be called. Multiple calls to GNUNET_SET_add_element() can be
+ * queued.
*
* @param set set to add element to
* @param element element to add to the set
* @param cont continuation called after the element has been added
- * @param cont_cls closure for cont
- * @return GNUNET_OK on success, GNUNET_SYSERR if the
+ * @param cont_cls closure for @a cont
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR if the
* set is invalid (e.g. the set service crashed)
*/
int
cont (cont_cls);
return GNUNET_SYSERR;
}
-
- mqm = GNUNET_MQ_msg_extra (msg, element->size, GNUNET_MESSAGE_TYPE_SET_ADD);
- msg->element_type = element->type;
- memcpy (&msg[1], element->data, element->size);
- GNUNET_MQ_notify_sent (mqm, cont, cont_cls);
+ mqm = GNUNET_MQ_msg_extra (msg, element->size,
+ GNUNET_MESSAGE_TYPE_SET_ADD);
+ msg->element_type = element->element_type;
+ memcpy (&msg[1],
+ element->data,
+ element->size);
+ GNUNET_MQ_notify_sent (mqm,
+ cont, cont_cls);
GNUNET_MQ_send (set->mq, mqm);
return GNUNET_OK;
}
/**
- * Remove an element to the given set.
- * After the element has been removed (in the sense of the
- * request being transmitted to the set service), cont will be called.
- * Calls to remove_element can be queued
+ * Remove an element to the given set. After the element has been
+ * removed (in the sense of the request being transmitted to the set
+ * service), @a cont will be called. Multiple calls to
+ * GNUNET_SET_remove_element() can be queued
*
* @param set set to remove element from
* @param element element to remove from the set
* @param cont continuation called after the element has been removed
- * @param cont_cls closure for cont
- * @return GNUNET_OK on success, GNUNET_SYSERR if the
+ * @param cont_cls closure for @a cont
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR if the
* set is invalid (e.g. the set service crashed)
*/
int
cont (cont_cls);
return GNUNET_SYSERR;
}
-
- mqm = GNUNET_MQ_msg_extra (msg, element->size, GNUNET_MESSAGE_TYPE_SET_REMOVE);
- msg->element_type = element->type;
- memcpy (&msg[1], element->data, element->size);
- GNUNET_MQ_notify_sent (mqm, cont, cont_cls);
+ mqm = GNUNET_MQ_msg_extra (msg,
+ element->size,
+ GNUNET_MESSAGE_TYPE_SET_REMOVE);
+ msg->element_type = element->element_type;
+ memcpy (&msg[1],
+ element->data,
+ element->size);
+ GNUNET_MQ_notify_sent (mqm,
+ cont, cont_cls);
GNUNET_MQ_send (set->mq, mqm);
return GNUNET_OK;
}
/**
- * Destroy the set handle, and free all associated resources.
+ * Destroy the set handle if no operations are left, mark the set
+ * for destruction otherwise.
+ *
+ * @param set set handle to destroy
*/
void
GNUNET_SET_destroy (struct GNUNET_SET_Handle *set)
{
+ /* destroying set while iterator is active is currently
+ not supported; we should expand the API to allow
+ clients to explicitly cancel the iteration! */
+ GNUNET_assert (NULL == set->iterator);
if (NULL != set->ops_head)
{
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Set operations are pending, delaying set destruction\n");
set->destroy_requested = GNUNET_YES;
return;
}
- GNUNET_CLIENT_disconnect (set->client);
- set->client = NULL;
- GNUNET_MQ_destroy (set->mq);
- set->mq = NULL;
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Really destroying set\n");
+ if (NULL != set->client)
+ {
+ GNUNET_CLIENT_disconnect (set->client);
+ set->client = NULL;
+ }
+ if (NULL != set->mq)
+ {
+ GNUNET_MQ_destroy (set->mq);
+ set->mq = NULL;
+ }
+ GNUNET_free (set);
}
/**
* Prepare a set operation to be evaluated with another peer.
* The evaluation will not start until the client provides
- * a local set with GNUNET_SET_commit.
+ * a local set with #GNUNET_SET_commit().
*
* @param other_peer peer with the other set
* @param app_id hash for the application using the set
* @param context_msg additional information for the request
- * @param salt salt used for the set operation; sometimes set operations
- * fail due to hash collisions, using a different salt for each operation
- * makes it harder for an attacker to exploit this
* @param result_mode specified how results will be returned,
- * see 'GNUNET_SET_ResultMode'.
+ * see `enum GNUNET_SET_ResultMode`.
* @param result_cb called on error or success
- * @param result_cls closure for result_cb
+ * @param result_cls closure for @e result_cb
* @return a handle to cancel the operation
*/
struct GNUNET_SET_OperationHandle *
GNUNET_SET_prepare (const struct GNUNET_PeerIdentity *other_peer,
const struct GNUNET_HashCode *app_id,
const struct GNUNET_MessageHeader *context_msg,
- uint16_t salt,
enum GNUNET_SET_ResultMode result_mode,
GNUNET_SET_ResultIterator result_cb,
void *result_cls)
oh = GNUNET_new (struct GNUNET_SET_OperationHandle);
oh->result_cb = result_cb;
oh->result_cls = result_cls;
-
- mqm = GNUNET_MQ_msg_nested_mh (msg, GNUNET_MESSAGE_TYPE_SET_EVALUATE, context_msg);
-
+ mqm = GNUNET_MQ_msg_nested_mh (msg,
+ GNUNET_MESSAGE_TYPE_SET_EVALUATE,
+ context_msg);
msg->app_id = *app_id;
+ msg->result_mode = htonl (result_mode);
msg->target_peer = *other_peer;
- msg->salt = salt;
- msg->reserved = 0;
oh->conclude_mqm = mqm;
oh->request_id_addr = &msg->request_id;
return oh;
}
+
+/**
+ * Connect to the set service in order to listen for requests.
+ *
+ * @param cls the `struct GNUNET_SET_ListenHandle *` to connect
+ * @param tc task context if invoked as a task, NULL otherwise
+ */
+static void
+listen_connect (void *cls,
+ const struct GNUNET_SCHEDULER_TaskContext *tc);
+
+
+/**
+ * Handle request message for a listen operation
+ *
+ * @param cls the listen handle
+ * @param mh the message
+ */
+static void
+handle_request (void *cls,
+ const struct GNUNET_MessageHeader *mh)
+{
+ struct GNUNET_SET_ListenHandle *lh = cls;
+ const struct GNUNET_SET_RequestMessage *msg;
+ struct GNUNET_SET_Request req;
+ const struct GNUNET_MessageHeader *context_msg;
+ uint16_t msize;
+ struct GNUNET_MQ_Envelope *mqm;
+ struct GNUNET_SET_RejectMessage *rmsg;
+
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Processing incoming operation request\n");
+ msize = ntohs (mh->size);
+ if (msize < sizeof (struct GNUNET_SET_RequestMessage))
+ {
+ GNUNET_break (0);
+ GNUNET_CLIENT_disconnect (lh->client);
+ lh->client = NULL;
+ GNUNET_MQ_destroy (lh->mq);
+ lh->mq = NULL;
+ lh->reconnect_task = GNUNET_SCHEDULER_add_delayed (lh->reconnect_backoff,
+ &listen_connect, lh);
+ lh->reconnect_backoff = GNUNET_TIME_STD_BACKOFF (lh->reconnect_backoff);
+ return;
+ }
+ /* we got another valid request => reset the backoff */
+ lh->reconnect_backoff = GNUNET_TIME_UNIT_MILLISECONDS;
+ msg = (const struct GNUNET_SET_RequestMessage *) mh;
+ req.accept_id = ntohl (msg->accept_id);
+ req.accepted = GNUNET_NO;
+ context_msg = GNUNET_MQ_extract_nested_mh (msg);
+ /* calling #GNUNET_SET_accept() in the listen cb will set req->accepted */
+ lh->listen_cb (lh->listen_cls,
+ &msg->peer_id,
+ context_msg,
+ &req);
+ if (GNUNET_YES == req.accepted)
+ return; /* the accept-case is handled in #GNUNET_SET_accept() */
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Rejecting request\n");
+ mqm = GNUNET_MQ_msg (rmsg,
+ GNUNET_MESSAGE_TYPE_SET_REJECT);
+ rmsg->accept_reject_id = msg->accept_id;
+ GNUNET_MQ_send (lh->mq, mqm);
+}
+
+
+/**
+ * Our connection with the set service encountered an error,
+ * re-initialize with exponential back-off.
+ *
+ * @param cls the `struct GNUNET_SET_ListenHandle *`
+ * @param error reason for the disconnect
+ */
+static void
+handle_client_listener_error (void *cls,
+ enum GNUNET_MQ_Error error)
+{
+ struct GNUNET_SET_ListenHandle *lh = cls;
+
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Listener broke down (%d), re-connecting\n",
+ (int) error);
+ GNUNET_CLIENT_disconnect (lh->client);
+ lh->client = NULL;
+ GNUNET_MQ_destroy (lh->mq);
+ lh->mq = NULL;
+ lh->reconnect_task = GNUNET_SCHEDULER_add_delayed (lh->reconnect_backoff,
+ &listen_connect, lh);
+ lh->reconnect_backoff = GNUNET_TIME_STD_BACKOFF (lh->reconnect_backoff);
+}
+
+
+/**
+ * Connect to the set service in order to listen for requests.
+ *
+ * @param cls the `struct GNUNET_SET_ListenHandle *` to connect
+ * @param tc task context if invoked as a task, NULL otherwise
+ */
+static void
+listen_connect (void *cls,
+ const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+ static const struct GNUNET_MQ_MessageHandler mq_handlers[] = {
+ { &handle_request, GNUNET_MESSAGE_TYPE_SET_REQUEST },
+ GNUNET_MQ_HANDLERS_END
+ };
+ struct GNUNET_SET_ListenHandle *lh = cls;
+ struct GNUNET_MQ_Envelope *mqm;
+ struct GNUNET_SET_ListenMessage *msg;
+
+ if ( (NULL != tc) &&
+ (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)) )
+ {
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Listener not reconnecting due to shutdown\n");
+ return;
+ }
+ lh->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
+ GNUNET_assert (NULL == lh->client);
+ lh->client = GNUNET_CLIENT_connect ("set", lh->cfg);
+ if (NULL == lh->client)
+ return;
+ GNUNET_assert (NULL == lh->mq);
+ lh->mq = GNUNET_MQ_queue_for_connection_client (lh->client,
+ mq_handlers,
+ &handle_client_listener_error, lh);
+ mqm = GNUNET_MQ_msg (msg, GNUNET_MESSAGE_TYPE_SET_LISTEN);
+ msg->operation = htonl (lh->operation);
+ msg->app_id = lh->app_id;
+ GNUNET_MQ_send (lh->mq, mqm);
+}
+
+
/**
* Wait for set operation requests for the given application id
- *
+ *
* @param cfg configuration to use for connecting to
- * the set service
+ * the set service, needs to be valid for the lifetime of the listen handle
* @param operation operation we want to listen for
* @param app_id id of the application that handles set operation requests
* @param listen_cb called for each incoming request matching the operation
* and application id
- * @param listen_cls handle for listen_cb
+ * @param listen_cls handle for @a listen_cb
* @return a handle that can be used to cancel the listen operation
*/
struct GNUNET_SET_ListenHandle *
void *listen_cls)
{
struct GNUNET_SET_ListenHandle *lh;
- struct GNUNET_MQ_Envelope *mqm;
- struct GNUNET_SET_ListenMessage *msg;
- static const struct GNUNET_MQ_MessageHandler mq_handlers[] = {
- {handle_request, GNUNET_MESSAGE_TYPE_SET_REQUEST},
- GNUNET_MQ_HANDLERS_END
- };
lh = GNUNET_new (struct GNUNET_SET_ListenHandle);
- lh->client = GNUNET_CLIENT_connect ("set", cfg);
lh->listen_cb = listen_cb;
lh->listen_cls = listen_cls;
- GNUNET_assert (NULL != lh->client);
- lh->mq = GNUNET_MQ_queue_for_connection_client (lh->client, mq_handlers,
- handle_client_listener_error, lh);
- mqm = GNUNET_MQ_msg (msg, GNUNET_MESSAGE_TYPE_SET_LISTEN);
- msg->operation = htons (operation);
- msg->app_id = *app_id;
- GNUNET_MQ_send (lh->mq, mqm);
-
+ lh->cfg = cfg;
+ lh->operation = operation;
+ lh->app_id = *app_id;
+ lh->reconnect_backoff = GNUNET_TIME_UNIT_MILLISECONDS;
+ listen_connect (lh, NULL);
+ if (NULL == lh->client)
+ {
+ GNUNET_free (lh);
+ return NULL;
+ }
return lh;
}
void
GNUNET_SET_listen_cancel (struct GNUNET_SET_ListenHandle *lh)
{
- GNUNET_CLIENT_disconnect (lh->client);
- GNUNET_MQ_destroy (lh->mq);
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Canceling listener\n");
+ if (NULL != lh->mq)
+ {
+ GNUNET_MQ_destroy (lh->mq);
+ lh->mq = NULL;
+ }
+ if (NULL != lh->client)
+ {
+ GNUNET_CLIENT_disconnect (lh->client);
+ lh->client = NULL;
+ }
+ if (GNUNET_SCHEDULER_NO_TASK != lh->reconnect_task)
+ {
+ GNUNET_SCHEDULER_cancel (lh->reconnect_task);
+ lh->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
+ }
GNUNET_free (lh);
}
/**
- * Accept a request we got via GNUNET_SET_listen. Must be called during
- * GNUNET_SET_listen, as the 'struct GNUNET_SET_Request' becomes invalid
+ * Accept a request we got via #GNUNET_SET_listen. Must be called during
+ * #GNUNET_SET_listen, as the 'struct GNUNET_SET_Request' becomes invalid
* afterwards.
- * Call GNUNET_SET_conclude to provide the local set to use for the operation,
- * and to begin the exchange with the remote peer.
+ * Call #GNUNET_SET_commit to provide the local set to use for the operation,
+ * and to begin the exchange with the remote peer.
*
* @param request request to accept
* @param result_mode specified how results will be returned,
- * see 'GNUNET_SET_ResultMode'.
+ * see `enum GNUNET_SET_ResultMode`.
* @param result_cb callback for the results
- * @param result_cls closure for result_cb
+ * @param result_cls closure for @a result_cb
* @return a handle to cancel the operation
*/
struct GNUNET_SET_OperationHandle *
{
struct GNUNET_MQ_Envelope *mqm;
struct GNUNET_SET_OperationHandle *oh;
- struct GNUNET_SET_AcceptRejectMessage *msg;
+ struct GNUNET_SET_AcceptMessage *msg;
- GNUNET_assert (NULL != request);
GNUNET_assert (GNUNET_NO == request->accepted);
request->accepted = GNUNET_YES;
-
+ mqm = GNUNET_MQ_msg (msg, GNUNET_MESSAGE_TYPE_SET_ACCEPT);
+ msg->accept_reject_id = htonl (request->accept_id);
+ msg->result_mode = htonl (result_mode);
oh = GNUNET_new (struct GNUNET_SET_OperationHandle);
oh->result_cb = result_cb;
oh->result_cls = result_cls;
-
- mqm = GNUNET_MQ_msg (msg, GNUNET_MESSAGE_TYPE_SET_ACCEPT);
- msg->accept_reject_id = htonl (request->accept_id);
-
oh->conclude_mqm = mqm;
oh->request_id_addr = &msg->request_id;
-
return oh;
}
-/**
- * Cancel the given set operation.
- * We need to send an explicit cancel message, as
- * all operations communicate with the set's client
- * handle.
- *
- * @param oh set operation to cancel
- */
-void
-GNUNET_SET_operation_cancel (struct GNUNET_SET_OperationHandle *oh)
-{
- if (NULL != oh->conclude_mqm)
- GNUNET_MQ_discard (oh->conclude_mqm);
-
- /* is the operation already commited? */
- if (NULL != oh->set)
- {
- struct GNUNET_SET_OperationHandle *h_assoc;
- struct GNUNET_MQ_Envelope *mqm;
-
- GNUNET_CONTAINER_DLL_remove (oh->set->ops_head, oh->set->ops_tail, oh);
- h_assoc = GNUNET_MQ_assoc_remove (oh->set->mq, oh->request_id);
- GNUNET_assert ((h_assoc == NULL) || (h_assoc == oh));
- mqm = GNUNET_MQ_msg_header (GNUNET_MESSAGE_TYPE_SET_CANCEL);
- GNUNET_MQ_send (oh->set->mq, mqm);
-
- if (GNUNET_YES == oh->set->destroy_requested)
- GNUNET_SET_destroy (oh->set);
- }
-
- GNUNET_free (oh);
-}
-
-
/**
* Commit a set to be used with a set operation.
* This function is called once we have fully constructed
* set information and call the result callback with the
* result information.
*
- * @param oh handle to the set operation
+ * @param oh handle to the set operation
* @param set the set to use for the operation
- * @return GNUNET_OK on success, GNUNET_SYSERR if the
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR if the
* set is invalid (e.g. the set service crashed)
*/
int
return GNUNET_SYSERR;
GNUNET_assert (NULL != oh->conclude_mqm);
oh->set = set;
- GNUNET_CONTAINER_DLL_insert (set->ops_head, set->ops_tail, oh);
+ GNUNET_CONTAINER_DLL_insert (set->ops_head,
+ set->ops_tail,
+ oh);
oh->request_id = GNUNET_MQ_assoc_add (set->mq, oh);
*oh->request_id_addr = htonl (oh->request_id);
GNUNET_MQ_send (set->mq, oh->conclude_mqm);
}
-
/**
- * Iterate over all elements in the given set.
- * Note that this operation involves transferring every element of the set
- * from the service to the client, and is thus costly.
+ * Iterate over all elements in the given set. Note that this
+ * operation involves transferring every element of the set from the
+ * service to the client, and is thus costly.
*
* @param set the set to iterate over
* @param iter the iterator to call for each element
- * @param cls closure for 'iter'
- * @return GNUNET_YES if the iteration started successfuly,
- * GNUNET_NO if another iteration is active
- * GNUNET_SYSERR if the set is invalid (e.g. the server crashed, disconnected)
+ * @param iter_cls closure for @a iter
+ * @return #GNUNET_YES if the iteration started successfuly,
+ * #GNUNET_NO if another iteration is active
+ * #GNUNET_SYSERR if the set is invalid (e.g. the server crashed, disconnected)
*/
int
-GNUNET_SET_iterate (struct GNUNET_SET_Handle *set, GNUNET_SET_ElementIterator iter, void *cls)
+GNUNET_SET_iterate (struct GNUNET_SET_Handle *set,
+ GNUNET_SET_ElementIterator iter,
+ void *iter_cls)
{
struct GNUNET_MQ_Envelope *ev;
GNUNET_assert (NULL != iter);
-
if (GNUNET_YES == set->invalid)
return GNUNET_SYSERR;
if (NULL != set->iterator)
return GNUNET_NO;
-
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Iterating over set\n");
set->iterator = iter;
- set->iterator_cls = cls;
+ set->iterator_cls = iter_cls;
ev = GNUNET_MQ_msg_header (GNUNET_MESSAGE_TYPE_SET_ITER_REQUEST);
GNUNET_MQ_send (set->mq, ev);
return GNUNET_YES;
}
+
+/**
+ * Stop iteration over all elements in the given set. Can only
+ * be called before the iteration has "naturally" completed its
+ * turn.
+ *
+ * @param set the set to stop iterating over
+ */
+void
+GNUNET_SET_iterate_cancel (struct GNUNET_SET_Handle *set)
+{
+ GNUNET_assert (NULL != set->iterator);
+ set->iterator = NULL;
+ set->iteration_id++;
+}
+
+
+/* end of set_api.c */