#define DEBUG_CLIENT GNUNET_NO
+/**
+ * How often do we re-try tranmsitting requests before giving up?
+ * Note that if we succeeded transmitting a request but failed to read
+ * a response, we do NOT re-try.
+ */
+#define MAX_ATTEMPTS 50
+
+/**
+ * Handle for a transmission request.
+ */
+struct GNUNET_CLIENT_TransmitHandle
+{
+ /**
+ * Connection state.
+ */
+ struct GNUNET_CLIENT_Connection *sock;
+
+ /**
+ * Function to call to get the data for transmission.
+ */
+ GNUNET_CONNECTION_TransmitReadyNotify notify;
+
+ /**
+ * Closure for notify.
+ */
+ void *notify_cls;
+
+ /**
+ * Handle to the transmission with the underlying
+ * connection.
+ */
+ struct GNUNET_CONNECTION_TransmitHandle *th;
+
+ /**
+ * If we are re-trying and are delaying to do so,
+ * handle to the scheduled task managing the delay.
+ */
+ GNUNET_SCHEDULER_TaskIdentifier reconnect_task;
+
+ /**
+ * Timeout for the operation overall.
+ */
+ struct GNUNET_TIME_Absolute timeout;
+
+ /**
+ * Number of bytes requested.
+ */
+ size_t size;
+
+ /**
+ * Are we allowed to re-try to connect without telling
+ * the user (of this API) about the connection troubles?
+ */
+ int auto_retry;
+
+ /**
+ * Number of attempts left for transmitting the request. We may
+ * fail the first time (say because the service is not yet up), in
+ * which case (if auto_retry is set) we wait a bit and re-try
+ * (timeout permitting).
+ */
+ unsigned int attempts_left;
+
+};
+
+
+/**
+ * Context for processing
+ * "GNUNET_CLIENT_transmit_and_get_response" requests.
+ */
+struct TransmitGetResponseContext
+{
+ /**
+ * Client handle.
+ */
+ struct GNUNET_CLIENT_Connection *sock;
+
+ /**
+ * Message to transmit; do not free, allocated
+ * right after this struct.
+ */
+ const struct GNUNET_MessageHeader *hdr;
+
+ /**
+ * Timeout to use.
+ */
+ struct GNUNET_TIME_Absolute timeout;
+
+ /**
+ * Function to call when done.
+ */
+ GNUNET_CLIENT_MessageHandler rn;
+
+ /**
+ * Closure for "rn".
+ */
+ void *rn_cls;
+};
+
/**
* Struct to refer to a GNUnet TCP connection.
* This is more than just a socket because if the server
struct GNUNET_CONNECTION_Handle *sock;
/**
- * Our scheduler.
+ * Our configuration.
+ * FIXME: why do we DUP the configuration? Avoid this!
*/
- struct GNUNET_SCHEDULER_Handle *sched;
+ struct GNUNET_CONFIGURATION_Handle *cfg;
/**
* Name of the service we interact with.
char *service_name;
/**
- * ID of task used for receiving.
+ * Context of a transmit_and_get_response operation, NULL
+ * if no such operation is pending.
*/
- GNUNET_SCHEDULER_TaskIdentifier receiver_task;
+ struct TransmitGetResponseContext *tag;
/**
* Handler for current receiver task.
*/
void *receiver_handler_cls;
+ /**
+ * Handle for a pending transmission request, NULL if there is
+ * none pending.
+ */
+ struct GNUNET_CLIENT_TransmitHandle *th;
+
/**
* Handler for service test completion (NULL unless in service_test)
*/
GNUNET_SCHEDULER_Task test_cb;
+ /**
+ * Deadline for calling 'test_cb'.
+ */
+ struct GNUNET_TIME_Absolute test_deadline;
+
+ /**
+ * If we are re-trying and are delaying to do so,
+ * handle to the scheduled task managing the delay.
+ */
+ GNUNET_SCHEDULER_TaskIdentifier receive_task;
+
/**
* Closure for test_cb (NULL unless in service_test)
*/
*/
struct GNUNET_TIME_Absolute receive_timeout;
+ /**
+ * Current value for our incremental back-off (for
+ * connect re-tries).
+ */
+ struct GNUNET_TIME_Relative back_off;
+
/**
* Number of bytes in received_buf that are valid.
*/
*/
int msg_complete;
+ /**
+ * Are we currently busy doing receive-processing?
+ * GNUNET_YES if so, GNUNET_NO if not.
+ */
+ int in_receive;
+
+ /**
+ * Are we ignoring shutdown signals?
+ */
+ int ignore_shutdown;
+
+ /**
+ * How often have we tried to connect?
+ */
+ unsigned int attempts;
+
};
/**
- * Get a connection with a service.
+ * Try to connect to the service.
*
- * @param sched scheduler to use
- * @param service_name name of the service
+ * @param service_name name of service to connect to
* @param cfg configuration to use
- * @return NULL on error (service unknown to configuration)
+ * @param attempt counter used to alternate between IP and UNIX domain sockets
+ * @return NULL on error
*/
-struct GNUNET_CLIENT_Connection *
-GNUNET_CLIENT_connect (struct GNUNET_SCHEDULER_Handle *sched,
- const char *service_name,
- const struct GNUNET_CONFIGURATION_Handle *cfg)
+static struct GNUNET_CONNECTION_Handle *
+do_connect (const char *service_name,
+ const struct GNUNET_CONFIGURATION_Handle *cfg,
+ unsigned int attempt)
{
- struct GNUNET_CLIENT_Connection *ret;
struct GNUNET_CONNECTION_Handle *sock;
char *hostname;
+ char *unixpath;
unsigned long long port;
+ sock = NULL;
+#if AF_UNIX
+ if (0 == (attempt % 2))
+ {
+ /* on even rounds, try UNIX */
+ if ((GNUNET_OK ==
+ GNUNET_CONFIGURATION_get_value_string (cfg,
+ service_name,
+ "UNIXPATH", &unixpath)) &&
+ (0 < strlen (unixpath))) /* We have a non-NULL unixpath, does that mean it's valid? */
+ {
+ sock = GNUNET_CONNECTION_create_from_connect_to_unixpath (cfg, unixpath);
+ if (sock != NULL)
+ {
+#if DEBUG_CLIENT
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Connected to unixpath `%s'!\n", unixpath);
+#endif
+ GNUNET_free(unixpath);
+ return sock;
+ }
+ }
+ GNUNET_free_non_null (unixpath);
+ }
+#endif
+
if ((GNUNET_OK !=
GNUNET_CONFIGURATION_get_value_number (cfg,
service_name,
"HOSTNAME", &hostname)))
{
GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
- "Could not determine valid hostname and port for service `%s' from configuration.\n",
+ _("Could not determine valid hostname and port for service `%s' from configuration.\n"),
service_name);
return NULL;
}
- sock = GNUNET_CONNECTION_create_from_connect (sched,
- hostname,
- port,
- GNUNET_SERVER_MAX_MESSAGE_SIZE);
+ if (0 == strlen (hostname))
+ {
+ GNUNET_free (hostname);
+ GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+ _("Need a non-empty hostname for service `%s'.\n"),
+ service_name);
+ return NULL;
+ }
+ if (port == 0)
+ {
+#if AF_UNIX
+ if (0 != (attempt % 2))
+ {
+ /* try UNIX */
+ if ((GNUNET_OK ==
+ GNUNET_CONFIGURATION_get_value_string (cfg,
+ service_name,
+ "UNIXPATH", &unixpath)) &&
+ (0 < strlen (unixpath)))
+ {
+ sock = GNUNET_CONNECTION_create_from_connect_to_unixpath (cfg,
+ unixpath);
+ GNUNET_free (unixpath);
+ if (sock != NULL)
+ return sock;
+ }
+ }
+#endif
+#if DEBUG_CLIENT
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Port is 0 for service `%s', UNIXPATH did not work, returning NULL!\n",
+ service_name);
+#endif
+ GNUNET_free (hostname);
+ return NULL;
+ }
+
+ sock = GNUNET_CONNECTION_create_from_connect (cfg,
+ hostname,
+ port);
GNUNET_free (hostname);
+ return sock;
+}
+
+
+/**
+ * Get a connection with a service.
+ *
+ * @param service_name name of the service
+ * @param cfg configuration to use
+ * @return NULL on error (service unknown to configuration)
+ */
+struct GNUNET_CLIENT_Connection *
+GNUNET_CLIENT_connect (const char *service_name,
+ const struct GNUNET_CONFIGURATION_Handle *cfg)
+{
+ struct GNUNET_CLIENT_Connection *ret;
+ struct GNUNET_CONNECTION_Handle *sock;
+
+ sock = do_connect (service_name,
+ cfg, 0);
if (sock == NULL)
return NULL;
ret = GNUNET_malloc (sizeof (struct GNUNET_CLIENT_Connection));
+ ret->attempts = 1;
ret->sock = sock;
- ret->sched = sched;
ret->service_name = GNUNET_strdup (service_name);
+ ret->cfg = GNUNET_CONFIGURATION_dup (cfg);
+ ret->back_off = GNUNET_TIME_UNIT_MILLISECONDS;
return ret;
}
/**
- * Receiver task has completed, free rest of client
- * data structures.
+ * Configure this connection to ignore shutdown signals.
+ *
+ * @param h client handle
+ * @param do_ignore GNUNET_YES to ignore, GNUNET_NO to restore default
*/
-static void
-finish_cleanup (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+void
+GNUNET_CLIENT_ignore_shutdown (struct GNUNET_CLIENT_Connection *h,
+ int do_ignore)
{
- struct GNUNET_CLIENT_Connection *sock = cls;
-
- GNUNET_array_grow (sock->received_buf, sock->received_size, 0);
- GNUNET_free (sock->service_name);
- GNUNET_free (sock);
+ h->ignore_shutdown = do_ignore;
+ if (h->sock != NULL)
+ GNUNET_CONNECTION_ignore_shutdown (h->sock,
+ do_ignore);
}
/**
- * Destroy connection with the service.
+ * Destroy connection with the service. This will automatically
+ * cancel any pending "receive" request (however, the handler will
+ * *NOT* be called, not even with a NULL message). Any pending
+ * transmission request will also be cancelled UNLESS the callback for
+ * the transmission request has already been called, in which case the
+ * transmission 'finish_pending_write' argument determines whether or
+ * not the write is guaranteed to complete before the socket is fully
+ * destroyed (unless, of course, there is an error with the server in
+ * which case the message may still be lost).
+ *
+ * @param finish_pending_write should a transmission already passed to the
+ * handle be completed?
+ * @param sock handle to the service connection
*/
void
-GNUNET_CLIENT_disconnect (struct GNUNET_CLIENT_Connection *sock)
+GNUNET_CLIENT_disconnect (struct GNUNET_CLIENT_Connection *sock,
+ int finish_pending_write)
{
GNUNET_assert (sock->sock != NULL);
- GNUNET_CONNECTION_destroy (sock->sock);
+ if (sock->in_receive == GNUNET_YES)
+ {
+ GNUNET_CONNECTION_receive_cancel (sock->sock);
+ sock->in_receive = GNUNET_NO;
+ }
+ GNUNET_CONNECTION_destroy (sock->sock, finish_pending_write);
sock->sock = NULL;
+ if (sock->tag != NULL)
+ {
+ GNUNET_free (sock->tag);
+ sock->tag = NULL;
+ }
sock->receiver_handler = NULL;
- GNUNET_SCHEDULER_add_after (sock->sched,
- GNUNET_YES,
- GNUNET_SCHEDULER_PRIORITY_KEEP,
- sock->receiver_task, &finish_cleanup, sock);
+ if (sock->th != NULL)
+ GNUNET_CLIENT_notify_transmit_ready_cancel (sock->th);
+ if (sock->receive_task != GNUNET_SCHEDULER_NO_TASK)
+ {
+ GNUNET_SCHEDULER_cancel (sock->receive_task);
+ sock->receive_task = GNUNET_SCHEDULER_NO_TASK;
+ }
+ GNUNET_array_grow (sock->received_buf, sock->received_size, 0);
+ GNUNET_free (sock->service_name);
+ GNUNET_CONFIGURATION_destroy (sock->cfg);
+ GNUNET_free (sock);
}
/**
- * check if message is complete
+ * Check if message is complete
*/
static void
check_complete (struct GNUNET_CLIENT_Connection *conn)
{
if ((conn->received_pos >= sizeof (struct GNUNET_MessageHeader)) &&
(conn->received_pos >=
- ntohs (((const struct GNUNET_MessageHeader *) conn->
- received_buf)->size)))
+ ntohs (((const struct GNUNET_MessageHeader *) conn->received_buf)->
+ size)))
conn->msg_complete = GNUNET_YES;
}
{
struct GNUNET_CLIENT_Connection *conn = cls;
struct GNUNET_TIME_Relative remaining;
+ GNUNET_CLIENT_MessageHandler receive_handler;
+ void *receive_handler_cls;
GNUNET_assert (conn->msg_complete == GNUNET_NO);
- conn->receiver_task = GNUNET_SCHEDULER_NO_TASK;
-
+ conn->in_receive = GNUNET_NO;
if ((available == 0) || (conn->sock == NULL) || (errCode != 0))
{
/* signal timeout! */
- if (conn->receiver_handler != NULL)
+#if DEBUG_CLIENT
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "timeout in receive_helper, available %d, conn->sock %s, errCode %d\n", available, conn->sock == NULL ? "NULL" : "non-NULL", errCode);
+#endif
+ if (NULL != (receive_handler = conn->receiver_handler))
{
- conn->receiver_handler (conn->receiver_handler_cls, NULL);
+ receive_handler_cls = conn->receiver_handler_cls;
conn->receiver_handler = NULL;
+ receive_handler (receive_handler_cls, NULL);
}
return;
}
check_complete (conn);
/* check for timeout */
remaining = GNUNET_TIME_absolute_get_remaining (conn->receive_timeout);
- if (remaining.value == 0)
+ if (remaining.rel_value == 0)
{
/* signal timeout! */
conn->receiver_handler (conn->receiver_handler_cls, NULL);
/**
* Continuation to call the receive callback.
+ *
+ * @param cls our handle to the client connection
+ * @param tc scheduler context
*/
static void
-receive_task (void *scls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+receive_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
{
- struct GNUNET_CLIENT_Connection *sock = scls;
+ struct GNUNET_CLIENT_Connection *sock = cls;
GNUNET_CLIENT_MessageHandler handler = sock->receiver_handler;
- const struct GNUNET_MessageHeader *cmsg = (const struct GNUNET_MessageHeader *) sock->received_buf;
- void *cls = sock->receiver_handler_cls;
+ const struct GNUNET_MessageHeader *cmsg =
+ (const struct GNUNET_MessageHeader *) sock->received_buf;
+ void *handler_cls = sock->receiver_handler_cls;
uint16_t msize = ntohs (cmsg->size);
char mbuf[msize];
- struct GNUNET_MessageHeader *msg = (struct GNUNET_MessageHeader*) mbuf;
+ struct GNUNET_MessageHeader *msg = (struct GNUNET_MessageHeader *) mbuf;
+#if DEBUG_CLIENT
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Received message of type %u and size %u\n",
+ ntohs (cmsg->type),
+ msize);
+#endif
+ sock->receive_task = GNUNET_SCHEDULER_NO_TASK;
GNUNET_assert (GNUNET_YES == sock->msg_complete);
- sock->receiver_task = GNUNET_SCHEDULER_NO_TASK;
GNUNET_assert (sock->received_pos >= msize);
memcpy (msg, cmsg, msize);
memmove (sock->received_buf,
- &sock->received_buf[msize], sock->received_pos - msize);
+ &sock->received_buf[msize], sock->received_pos - msize);
sock->received_pos -= msize;
sock->msg_complete = GNUNET_NO;
- sock->receiver_handler = NULL;
+ sock->receiver_handler = NULL;
check_complete (sock);
if (handler != NULL)
- handler (cls, msg);
+ handler (handler_cls, msg);
}
handler (handler_cls, NULL);
return;
}
- GNUNET_assert (sock->receiver_task ==
- GNUNET_SCHEDULER_NO_TASK);
sock->receiver_handler = handler;
sock->receiver_handler_cls = handler_cls;
sock->receive_timeout = GNUNET_TIME_relative_to_absolute (timeout);
if (GNUNET_YES == sock->msg_complete)
- sock->receiver_task = GNUNET_SCHEDULER_add_after (sock->sched,
- GNUNET_YES,
- GNUNET_SCHEDULER_PRIORITY_KEEP,
- GNUNET_SCHEDULER_NO_TASK,
- &receive_task, sock);
+ {
+ sock->receive_task = GNUNET_SCHEDULER_add_after (GNUNET_SCHEDULER_NO_TASK,
+ &receive_task, sock);
+ }
else
- sock->receiver_task = GNUNET_CONNECTION_receive (sock->sock,
- GNUNET_SERVER_MAX_MESSAGE_SIZE,
- timeout,
- &receive_helper, sock);
-}
-
-
-static size_t
-write_shutdown (void *cls, size_t size, void *buf)
-{
- struct GNUNET_MessageHeader *msg;
-
- if (size < sizeof (struct GNUNET_MessageHeader))
- return 0; /* client disconnected */
- msg = (struct GNUNET_MessageHeader *) buf;
- msg->type = htons (GNUNET_MESSAGE_TYPE_SHUTDOWN);
- msg->size = htons (sizeof (struct GNUNET_MessageHeader));
- return sizeof (struct GNUNET_MessageHeader);
-}
-
-
-/**
- * Request that the service should shutdown.
- * Afterwards, the connection should be disconnected.
- *
- * @param sock the socket connected to the service
- */
-void
-GNUNET_CLIENT_service_shutdown (struct GNUNET_CLIENT_Connection *sock)
-{
- GNUNET_CONNECTION_notify_transmit_ready (sock->sock,
- sizeof (struct GNUNET_MessageHeader),
- GNUNET_TIME_UNIT_FOREVER_REL,
- &write_shutdown, NULL);
+ {
+ GNUNET_assert (sock->in_receive == GNUNET_NO);
+ sock->in_receive = GNUNET_YES;
+#if DEBUG_CLIENT
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "calling GNUNET_CONNECTION_receive\n");
+#endif
+ GNUNET_CONNECTION_receive (sock->sock,
+ GNUNET_SERVER_MAX_MESSAGE_SIZE - 1,
+ timeout, &receive_helper, sock);
+ }
}
* Report service unavailable.
*/
static void
-service_test_error (struct GNUNET_SCHEDULER_Handle *s,
- GNUNET_SCHEDULER_Task task, void *task_cls)
+service_test_error (GNUNET_SCHEDULER_Task task, void *task_cls)
{
- GNUNET_SCHEDULER_add_continuation (s,
- GNUNET_YES,
- task,
+ GNUNET_SCHEDULER_add_continuation (task,
task_cls,
GNUNET_SCHEDULER_REASON_TIMEOUT);
}
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Received confirmation that service is running.\n");
#endif
- GNUNET_SCHEDULER_add_continuation (conn->sched,
- GNUNET_YES,
- conn->test_cb,
+ GNUNET_SCHEDULER_add_continuation (conn->test_cb,
conn->test_cb_cls,
GNUNET_SCHEDULER_REASON_PREREQ_DONE);
}
else
{
- service_test_error (conn->sched, conn->test_cb, conn->test_cb_cls);
+ service_test_error (conn->test_cb, conn->test_cb_cls);
}
- GNUNET_CLIENT_disconnect (conn);
+ GNUNET_CLIENT_disconnect (conn, GNUNET_NO);
}
static size_t
write_test (void *cls, size_t size, void *buf)
{
+ struct GNUNET_CLIENT_Connection *conn = cls;
struct GNUNET_MessageHeader *msg;
if (size < sizeof (struct GNUNET_MessageHeader))
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
_("Failure to transmit TEST request.\n"));
#endif
+ service_test_error (conn->test_cb, conn->test_cb_cls);
+ GNUNET_CLIENT_disconnect (conn, GNUNET_NO);
return 0; /* client disconnected */
}
#if DEBUG_CLIENT
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, _("Transmitting TEST request.\n"));
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Transmitting `%s' request.\n", "TEST");
#endif
msg = (struct GNUNET_MessageHeader *) buf;
msg->type = htons (GNUNET_MESSAGE_TYPE_TEST);
msg->size = htons (sizeof (struct GNUNET_MessageHeader));
+ GNUNET_CLIENT_receive (conn,
+ &confirm_handler,
+ conn,
+ GNUNET_TIME_absolute_get_remaining (conn->test_deadline));
return sizeof (struct GNUNET_MessageHeader);
}
/**
* Wait until the service is running.
*
- * @param sched scheduler to use
* @param service name of the service to wait for
* @param cfg configuration to use
* @param timeout how long to wait at most in ms
* @param task_cls closure for task
*/
void
-GNUNET_CLIENT_service_test (struct GNUNET_SCHEDULER_Handle *sched,
- const char *service,
+GNUNET_CLIENT_service_test (const char *service,
const struct GNUNET_CONFIGURATION_Handle *cfg,
struct GNUNET_TIME_Relative timeout,
GNUNET_SCHEDULER_Task task, void *task_cls)
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Testing if service `%s' is running.\n", service);
#endif
- conn = GNUNET_CLIENT_connect (sched, service, cfg);
+ conn = GNUNET_CLIENT_connect (service, cfg);
if (conn == NULL)
{
GNUNET_log (GNUNET_ERROR_TYPE_INFO,
_
("Could not connect to service `%s', must not be running.\n"),
service);
- service_test_error (sched, task, task_cls);
+ service_test_error (task, task_cls);
return;
}
conn->test_cb = task;
conn->test_cb_cls = task_cls;
- if (NULL ==
- GNUNET_CONNECTION_notify_transmit_ready (conn->sock,
- sizeof (struct
- GNUNET_MessageHeader),
- timeout, &write_test, NULL))
+ conn->test_deadline = GNUNET_TIME_relative_to_absolute (timeout);
+
+ if (NULL == GNUNET_CLIENT_notify_transmit_ready (conn,
+ sizeof (struct GNUNET_MessageHeader),
+ timeout,
+ GNUNET_YES,
+ &write_test, conn))
{
GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
_("Failure to transmit request to service `%s'\n"),
service);
- service_test_error (sched, task, task_cls);
- GNUNET_CLIENT_disconnect (conn);
+ service_test_error (task, task_cls);
+ GNUNET_CLIENT_disconnect (conn, GNUNET_NO);
+ return;
+ }
+}
+
+
+/**
+ * Connection notifies us about failure or success of
+ * a transmission request. Either pass it on to our
+ * user or, if possible, retry.
+ *
+ * @param cls our "struct GNUNET_CLIENT_TransmissionHandle"
+ * @param size number of bytes available for transmission
+ * @param buf where to write them
+ * @return number of bytes written to buf
+ */
+static size_t client_notify (void *cls, size_t size, void *buf);
+
+
+/**
+ * This task is run if we should re-try connection to the
+ * service after a while.
+ *
+ * @param cls our "struct GNUNET_CLIENT_TransmitHandle" of the request
+ * @param tc unused
+ */
+static void
+client_delayed_retry (void *cls,
+ const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+ struct GNUNET_CLIENT_TransmitHandle *th = cls;
+
+ th->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
+ if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
+ {
+#if DEBUG_CLIENT
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Transmission failed due to shutdown.\n");
+#endif
+ th->sock->th = NULL;
+ th->notify (th->notify_cls, 0, NULL);
+ GNUNET_free (th);
+ return;
+ }
+ th->th = GNUNET_CONNECTION_notify_transmit_ready (th->sock->sock,
+ th->size,
+ GNUNET_TIME_absolute_get_remaining
+ (th->timeout),
+ &client_notify, th);
+ if (th->th == NULL)
+ {
+ GNUNET_break (0);
+ th->notify (th->notify_cls, 0, NULL);
+ GNUNET_free (th);
return;
}
- GNUNET_CLIENT_receive (conn, &confirm_handler, conn, timeout);
+}
+
+
+/**
+ * Connection notifies us about failure or success of a transmission
+ * request. Either pass it on to our user or, if possible, retry.
+ *
+ * @param cls our "struct GNUNET_CLIENT_TransmissionHandle"
+ * @param size number of bytes available for transmission
+ * @param buf where to write them
+ * @return number of bytes written to buf
+ */
+static size_t
+client_notify (void *cls, size_t size, void *buf)
+{
+ struct GNUNET_CLIENT_TransmitHandle *th = cls;
+ size_t ret;
+ struct GNUNET_TIME_Relative delay;
+
+ th->th = NULL;
+ th->sock->th = NULL;
+ if (buf == NULL)
+ {
+ delay = GNUNET_TIME_absolute_get_remaining (th->timeout);
+ delay.rel_value /= 2;
+ if ( (0 != (GNUNET_SCHEDULER_REASON_SHUTDOWN & GNUNET_SCHEDULER_get_reason ())) ||
+ (GNUNET_YES != th->auto_retry) ||
+ (0 == --th->attempts_left) ||
+ (delay.rel_value < 1) )
+ {
+#if DEBUG_CLIENT
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Transmission failed %u times, giving up.\n",
+ MAX_ATTEMPTS - th->attempts_left);
+#endif
+ GNUNET_break (0 == th->notify (th->notify_cls, 0, NULL));
+ GNUNET_free (th);
+ return 0;
+ }
+ /* auto-retry */
+ GNUNET_CONNECTION_destroy (th->sock->sock, GNUNET_NO);
+ th->sock->sock = do_connect (th->sock->service_name,
+ th->sock->cfg,
+ th->sock->attempts++);
+ GNUNET_assert (NULL != th->sock->sock);
+ GNUNET_CONNECTION_ignore_shutdown (th->sock->sock,
+ th->sock->ignore_shutdown);
+ delay = GNUNET_TIME_relative_min (delay, th->sock->back_off);
+ th->sock->back_off
+ = GNUNET_TIME_relative_min (GNUNET_TIME_relative_multiply (th->sock->back_off, 2),
+ GNUNET_TIME_UNIT_SECONDS);
+#if DEBUG_CLIENT
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Transmission failed %u times, trying again in %llums.\n",
+ MAX_ATTEMPTS - th->attempts_left,
+ (unsigned long long) delay.rel_value);
+#endif
+ th->reconnect_task = GNUNET_SCHEDULER_add_delayed (delay,
+ &client_delayed_retry,
+ th);
+ th->sock->th = th;
+ return 0;
+ }
+ GNUNET_assert (size >= th->size);
+ ret = th->notify (th->notify_cls, size, buf);
+ GNUNET_free (th);
+ return ret;
}
* @param size number of bytes to send
* @param timeout after how long should we give up (and call
* notify with buf NULL and size 0)?
+ * @param auto_retry if the connection to the service dies, should we
+ * automatically re-connect and retry (within the timeout period)
+ * or should we immediately fail in this case? Pass GNUNET_YES
+ * if the caller does not care about temporary connection errors,
+ * for example because the protocol is stateless
* @param notify function to call
* @param notify_cls closure for notify
* @return NULL if our buffer will never hold size bytes,
* a handle if the notify callback was queued (can be used to cancel)
*/
-struct GNUNET_CONNECTION_TransmitHandle *
+struct GNUNET_CLIENT_TransmitHandle *
GNUNET_CLIENT_notify_transmit_ready (struct GNUNET_CLIENT_Connection *sock,
size_t size,
struct GNUNET_TIME_Relative timeout,
+ int auto_retry,
GNUNET_CONNECTION_TransmitReadyNotify
notify, void *notify_cls)
{
- return GNUNET_CONNECTION_notify_transmit_ready (sock->sock,
- size,
- timeout, notify, notify_cls);
+ struct GNUNET_CLIENT_TransmitHandle *th;
+
+ if (NULL != sock->th)
+ return NULL;
+ th = GNUNET_malloc (sizeof (struct GNUNET_CLIENT_TransmitHandle));
+ th->sock = sock;
+ th->size = size;
+ th->timeout = GNUNET_TIME_relative_to_absolute (timeout);
+ th->auto_retry = auto_retry;
+ th->notify = notify;
+ th->notify_cls = notify_cls;
+ th->attempts_left = MAX_ATTEMPTS;
+ th->th = GNUNET_CONNECTION_notify_transmit_ready (sock->sock,
+ size,
+ timeout,
+ &client_notify, th);
+ if (NULL == th->th)
+ {
+ GNUNET_break (0);
+ GNUNET_free (th);
+ return NULL;
+ }
+ sock->th = th;
+ return th;
}
/**
- * Context for processing
- * "GNUNET_CLIENT_transmit_and_get_response" requests.
+ * Cancel a request for notification.
+ *
+ * @param th handle from the original request.
*/
-struct TARCtx
+void
+GNUNET_CLIENT_notify_transmit_ready_cancel (struct
+ GNUNET_CLIENT_TransmitHandle *th)
{
- /**
- * Client handle.
- */
- struct GNUNET_CLIENT_Connection *sock;
-
- /**
- * Message to transmit; do not free, allocated
- * right after this struct.
- */
- const struct GNUNET_MessageHeader *hdr;
-
- /**
- * Timeout to use.
- */
- struct GNUNET_TIME_Absolute timeout;
-
- /**
- * Function to call when done.
- */
- GNUNET_CLIENT_MessageHandler rn;
-
- /**
- * Closure for "rn".
- */
- void *rn_cls;
-};
+ if (th->reconnect_task != GNUNET_SCHEDULER_NO_TASK)
+ {
+ GNUNET_break (NULL == th->th);
+ GNUNET_SCHEDULER_cancel (th->reconnect_task);
+ th->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
+ }
+ else
+ {
+ GNUNET_assert (NULL != th->th);
+ GNUNET_CONNECTION_notify_transmit_ready_cancel (th->th);
+ }
+ th->sock->th = NULL;
+ GNUNET_free (th);
+}
/**
* NULL and "size" zero if the socket was closed for
* writing in the meantime.
*
- * @param cls closure of type "struct TARCtx*"
+ * @param cls closure of type "struct TransmitGetResponseContext*"
* @param size number of bytes available in buf
* @param buf where the callee should write the message
* @return number of bytes written to buf
*/
static size_t
-transmit_for_response (void *cls,
- size_t size,
- void *buf)
+transmit_for_response (void *cls, size_t size, void *buf)
{
- struct TARCtx *tc = cls;
+ struct TransmitGetResponseContext *tc = cls;
uint16_t msize;
- msize = ntohs(tc->hdr->size);
+ tc->sock->tag = NULL;
+ msize = ntohs (tc->hdr->size);
if (NULL == buf)
{
+#if DEBUG_CLIENT
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ _("Could not submit request, not expecting to receive a response.\n"));
+#endif
tc->rn (tc->rn_cls, NULL);
GNUNET_free (tc);
return 0;
GNUNET_assert (size >= msize);
memcpy (buf, tc->hdr, msize);
GNUNET_CLIENT_receive (tc->sock,
- tc->rn,
- tc->rn_cls,
- GNUNET_TIME_absolute_get_remaining (tc->timeout));
+ tc->rn,
+ tc->rn_cls,
+ GNUNET_TIME_absolute_get_remaining (tc->timeout));
GNUNET_free (tc);
return msize;
}
* @param hdr message to transmit
* @param timeout when to give up (for both transmission
* and for waiting for a response)
+ * @param auto_retry if the connection to the service dies, should we
+ * automatically re-connect and retry (within the timeout period)
+ * or should we immediately fail in this case? Pass GNUNET_YES
+ * if the caller does not care about temporary connection errors,
+ * for example because the protocol is stateless
* @param rn function to call with the response
* @param rn_cls closure for rn
+ * @return GNUNET_OK on success, GNUNET_SYSERR if a request
+ * is already pending
*/
-void
-GNUNET_CLIENT_transmit_and_get_response (struct GNUNET_CLIENT_Connection *sock,
- const struct GNUNET_MessageHeader *hdr,
- struct GNUNET_TIME_Relative timeout,
- GNUNET_CLIENT_MessageHandler rn,
- void *rn_cls)
+int
+GNUNET_CLIENT_transmit_and_get_response (struct GNUNET_CLIENT_Connection
+ *sock,
+ const struct GNUNET_MessageHeader
+ *hdr,
+ struct GNUNET_TIME_Relative timeout,
+ int auto_retry,
+ GNUNET_CLIENT_MessageHandler rn,
+ void *rn_cls)
{
- struct TARCtx *tc;
+ struct TransmitGetResponseContext *tc;
uint16_t msize;
- msize = ntohs(hdr->size);
- tc = GNUNET_malloc(sizeof (struct TARCtx) + msize);
+ if (NULL != sock->th)
+ return GNUNET_SYSERR;
+ GNUNET_assert (sock->tag == NULL);
+ msize = ntohs (hdr->size);
+ tc = GNUNET_malloc (sizeof (struct TransmitGetResponseContext) + msize);
tc->sock = sock;
- tc->hdr = (const struct GNUNET_MessageHeader*) &tc[1];
+ tc->hdr = (const struct GNUNET_MessageHeader *) &tc[1];
memcpy (&tc[1], hdr, msize);
tc->timeout = GNUNET_TIME_relative_to_absolute (timeout);
tc->rn = rn;
tc->rn_cls = rn_cls;
- GNUNET_CLIENT_notify_transmit_ready (sock,
- msize,
- timeout,
- &transmit_for_response,
- tc);
+ if (NULL == GNUNET_CLIENT_notify_transmit_ready (sock,
+ msize,
+ timeout,
+ auto_retry,
+ &transmit_for_response,
+ tc))
+ {
+ GNUNET_break (0);
+ GNUNET_free (tc);
+ return GNUNET_SYSERR;
+ }
+ sock->tag = tc;
+ return GNUNET_OK;
}
projects / oweals / gnunet.git / blobdiff