/*
This file is part of GNUnet.
- (C) 2001, 2002, 2006, 2008, 2009 Christian Grothoff (and other contributing authors)
+ Copyright (C) 2001-2013 GNUnet e.V.
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
You should have received a copy of the GNU General Public License
along with GNUnet; see the file COPYING. If not, write to the
- Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA.
+ Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ Boston, MA 02110-1301, USA.
*/
/**
* Generic TCP code for reliable, record-oriented TCP
* connections between clients and service providers.
*/
-
#include "platform.h"
-#include "gnunet_common.h"
-#include "gnunet_client_lib.h"
#include "gnunet_protocols.h"
-#include "gnunet_server_lib.h"
-#include "gnunet_scheduler_lib.h"
+#include "gnunet_util_lib.h"
+#include "gnunet_socks.h"
+
+
+/**
+ * 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
-#define DEBUG_CLIENT GNUNET_NO
+#define LOG(kind,...) GNUNET_log_from (kind, "util",__VA_ARGS__)
+
+/**
+ * Handle for a transmission request.
+ */
+struct GNUNET_CLIENT_TransmitHandle
+{
+ /**
+ * Connection state.
+ */
+ struct GNUNET_CLIENT_Connection *client;
+
+ /**
+ * Function to call to get the data for transmission.
+ */
+ GNUNET_CONNECTION_TransmitReadyNotify notify;
+
+ /**
+ * Closure for @e 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.
+ */
+ struct GNUNET_SCHEDULER_Task *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 *client;
+
+ /**
+ * 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 @e rn.
+ */
+ void *rn_cls;
+};
/**
* Struct to refer to a GNUnet TCP connection.
{
/**
- * the socket handle, NULL if not live
+ * The connection handle, NULL if not live
*/
- struct GNUNET_CONNECTION_Handle *sock;
+ struct GNUNET_CONNECTION_Handle *connection;
/**
- * Our scheduler.
+ * Our configuration.
*/
- struct GNUNET_SCHEDULER_Handle *sched;
+ const 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.
GNUNET_CLIENT_MessageHandler receiver_handler;
/**
- * Closure for receiver_handler.
+ * Closure for @e receiver_handler.
*/
void *receiver_handler_cls;
/**
- * Handler for service test completion (NULL unless in service_test)
+ * Handle for a pending transmission request, NULL if there is
+ * none pending.
*/
- GNUNET_SCHEDULER_Task test_cb;
+ struct GNUNET_CLIENT_TransmitHandle *th;
/**
- * Closure for test_cb (NULL unless in service_test)
+ * If we are re-trying and are delaying to do so,
+ * handle to the scheduled task managing the delay.
*/
- void *test_cb_cls;
+ struct GNUNET_SCHEDULER_Task * receive_task;
/**
* Buffer for received message.
*/
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. #GNUNET_SYSERR
+ * if the connection has failed (but we may not have
+ * closed the handle itself yet).
+ */
+ int in_receive;
+
+ /**
+ * Is this the first message we are sending to the service?
+ */
+ int first_message;
+
+ /**
+ * How often have we tried to connect?
+ */
+ unsigned int attempts;
+
};
/**
- * Get a connection with a service.
+ * Try connecting to the server using UNIX domain sockets.
*
- * @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)
+ * @return NULL on error, connection to UNIX otherwise
*/
-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 *
+try_unixpath (const char *service_name,
+ const struct GNUNET_CONFIGURATION_Handle *cfg)
+{
+#if AF_UNIX
+ struct GNUNET_CONNECTION_Handle *connection;
+ char *unixpath;
+ struct sockaddr_un s_un;
+
+ unixpath = NULL;
+ if ((GNUNET_OK == GNUNET_CONFIGURATION_get_value_filename (cfg, service_name, "UNIXPATH", &unixpath)) &&
+ (0 < strlen (unixpath)))
+ {
+ /* We have a non-NULL unixpath, need to validate it */
+ if (strlen (unixpath) >= sizeof (s_un.sun_path))
+ {
+ LOG (GNUNET_ERROR_TYPE_WARNING,
+ _("UNIXPATH `%s' too long, maximum length is %llu\n"), unixpath,
+ (unsigned long long) sizeof (s_un.sun_path));
+ unixpath = GNUNET_NETWORK_shorten_unixpath (unixpath);
+ LOG (GNUNET_ERROR_TYPE_INFO,
+ _("Using `%s' instead\n"), unixpath);
+ if (NULL == unixpath)
+ return NULL;
+ }
+ connection = GNUNET_CONNECTION_create_from_connect_to_unixpath (cfg, unixpath);
+ if (NULL != connection)
+ {
+ LOG (GNUNET_ERROR_TYPE_DEBUG, "Connected to unixpath `%s'!\n",
+ unixpath);
+ GNUNET_free (unixpath);
+ return connection;
+ }
+ }
+ GNUNET_free_non_null (unixpath);
+#endif
+ return NULL;
+}
+
+
+/**
+ * Test whether the configuration has proper values for connection
+ * (UNIXPATH || (PORT && HOSTNAME)).
+ *
+ * @param service_name name of service to connect to
+ * @param cfg configuration to use
+ * @return #GNUNET_OK if the configuration is valid, #GNUNET_SYSERR if not
+ */
+static int
+test_service_configuration (const char *service_name,
+ const struct GNUNET_CONFIGURATION_Handle *cfg)
{
- struct GNUNET_CLIENT_Connection *ret;
- struct GNUNET_CONNECTION_Handle *sock;
+ int ret = GNUNET_SYSERR;
+ char *hostname = NULL;
+ unsigned long long port;
+#if AF_UNIX
+ char *unixpath = NULL;
+
+ if ((GNUNET_OK == GNUNET_CONFIGURATION_get_value_filename (cfg, service_name, "UNIXPATH", &unixpath)) &&
+ (0 < strlen (unixpath)))
+ ret = GNUNET_OK;
+ GNUNET_free_non_null (unixpath);
+#endif
+
+ if ( (GNUNET_YES ==
+ GNUNET_CONFIGURATION_have_value (cfg, service_name, "PORT")) &&
+ (GNUNET_OK ==
+ GNUNET_CONFIGURATION_get_value_number (cfg, service_name, "PORT", &port)) &&
+ (port <= 65535) && (0 != port) &&
+ (GNUNET_OK ==
+ GNUNET_CONFIGURATION_get_value_string (cfg, service_name, "HOSTNAME",
+ &hostname)) &&
+ (0 != strlen (hostname)) )
+ ret = GNUNET_OK;
+ GNUNET_free_non_null (hostname);
+ return ret;
+}
+
+
+/**
+ * Try to connect to the service.
+ *
+ * @param service_name name of service to connect to
+ * @param cfg configuration to use
+ * @param attempt counter used to alternate between IP and UNIX domain sockets
+ * @return NULL on error
+ */
+static struct GNUNET_CONNECTION_Handle *
+do_connect (const char *service_name,
+ const struct GNUNET_CONFIGURATION_Handle *cfg,
+ unsigned int attempt)
+{
+ struct GNUNET_CONNECTION_Handle *connection;
char *hostname;
unsigned long long port;
- if ((GNUNET_OK !=
- GNUNET_CONFIGURATION_get_value_number (cfg,
- service_name,
- "PORT",
- &port)) ||
- (port > 65535) ||
- (GNUNET_OK !=
- GNUNET_CONFIGURATION_get_value_string (cfg,
- service_name,
- "HOSTNAME", &hostname)))
+ /* Never use a local source if a proxy is configured */
+ if (GNUNET_YES == GNUNET_SOCKS_check_service (service_name,cfg))
+ return GNUNET_SOCKS_do_connect (service_name,cfg);
+
+ connection = NULL;
+ if (0 == (attempt % 2))
+ {
+ /* on even rounds, try UNIX first */
+ connection = try_unixpath (service_name, cfg);
+ if (NULL != connection)
+ return connection;
+ }
+ if (GNUNET_YES ==
+ GNUNET_CONFIGURATION_have_value (cfg, service_name, "PORT"))
+ {
+ if ((GNUNET_OK !=
+ GNUNET_CONFIGURATION_get_value_number (cfg, service_name, "PORT", &port))
+ || (port > 65535) ||
+ (GNUNET_OK !=
+ GNUNET_CONFIGURATION_get_value_string (cfg, service_name, "HOSTNAME",
+ &hostname)))
{
- GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
- "Could not determine valid hostname and port for service `%s' from configuration.\n",
- service_name);
+ LOG (GNUNET_ERROR_TYPE_WARNING,
+ _
+ ("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);
- GNUNET_free (hostname);
- if (sock == NULL)
+ if (0 == strlen (hostname))
+ {
+ GNUNET_free (hostname);
+ LOG (GNUNET_ERROR_TYPE_WARNING,
+ _("Need a non-empty hostname for service `%s'.\n"), service_name);
+ return NULL;
+ }
+ }
+ else
+ {
+ /* unspecified means 0 (disabled) */
+ port = 0;
+ hostname = NULL;
+ }
+ if (0 == port)
+ {
+ /* if port is 0, try UNIX */
+ connection = try_unixpath (service_name, cfg);
+ if (NULL != connection)
+ {
+ GNUNET_free_non_null (hostname);
+ return connection;
+ }
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Port is 0 for service `%s', UNIXPATH did not work, returning NULL!\n",
+ service_name);
+ GNUNET_free_non_null (hostname);
return NULL;
- ret = GNUNET_malloc (sizeof (struct GNUNET_CLIENT_Connection));
- ret->sock = sock;
- ret->sched = sched;
- ret->service_name = GNUNET_strdup (service_name);
- return ret;
+ }
+ connection = GNUNET_CONNECTION_create_from_connect (cfg, hostname, port);
+ GNUNET_free (hostname);
+ return connection;
}
/**
- * Receiver task has completed, free rest of client
- * data structures.
+ * 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)
*/
-static void
-finish_cleanup (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+struct GNUNET_CLIENT_Connection *
+GNUNET_CLIENT_connect (const char *service_name,
+ const struct GNUNET_CONFIGURATION_Handle *cfg)
{
- struct GNUNET_CLIENT_Connection *sock = cls;
+ struct GNUNET_CLIENT_Connection *client;
+ struct GNUNET_CONNECTION_Handle *connection;
- GNUNET_array_grow (sock->received_buf, sock->received_size, 0);
- GNUNET_free (sock->service_name);
- GNUNET_free (sock);
+ if (GNUNET_OK !=
+ test_service_configuration (service_name,
+ cfg))
+ return NULL;
+ connection = do_connect (service_name, cfg, 0);
+ client = GNUNET_new (struct GNUNET_CLIENT_Connection);
+ client->first_message = GNUNET_YES;
+ client->attempts = 1;
+ client->connection = connection;
+ client->service_name = GNUNET_strdup (service_name);
+ client->cfg = cfg;
+ client->back_off = GNUNET_TIME_UNIT_MILLISECONDS;
+ return client;
}
/**
- * 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 client handle to the service connection
*/
void
-GNUNET_CLIENT_disconnect (struct GNUNET_CLIENT_Connection *sock)
+GNUNET_CLIENT_disconnect (struct GNUNET_CLIENT_Connection *client)
{
- GNUNET_assert (sock->sock != NULL);
- GNUNET_CONNECTION_destroy (sock->sock);
- sock->sock = NULL;
- sock->receiver_handler = NULL;
- GNUNET_SCHEDULER_add_after (sock->sched,
- GNUNET_YES,
- GNUNET_SCHEDULER_PRIORITY_KEEP,
- sock->receiver_task, &finish_cleanup, sock);
+ if (GNUNET_YES == client->in_receive)
+ {
+ GNUNET_CONNECTION_receive_cancel (client->connection);
+ client->in_receive = GNUNET_NO;
+ }
+ if (NULL != client->th)
+ {
+ GNUNET_CLIENT_notify_transmit_ready_cancel (client->th);
+ client->th = NULL;
+ }
+ if (NULL != client->connection)
+ {
+ GNUNET_CONNECTION_destroy (client->connection);
+ client->connection = NULL;
+ }
+ if (NULL != client->receive_task)
+ {
+ GNUNET_SCHEDULER_cancel (client->receive_task);
+ client->receive_task = NULL;
+ }
+ if (NULL != client->tag)
+ {
+ GNUNET_free (client->tag);
+ client->tag = NULL;
+ }
+ client->receiver_handler = NULL;
+ GNUNET_array_grow (client->received_buf, client->received_size, 0);
+ GNUNET_free (client->service_name);
+ GNUNET_free (client);
}
/**
- * check if message is complete
+ * Check if message is complete. Sets the "msg_complete" member
+ * in the client struct.
+ *
+ * @param client connection with the buffer to check
*/
static void
-check_complete (struct GNUNET_CLIENT_Connection *conn)
+check_complete (struct GNUNET_CLIENT_Connection *client)
{
- if ((conn->received_pos >= sizeof (struct GNUNET_MessageHeader)) &&
- (conn->received_pos >=
- ntohs (((const struct GNUNET_MessageHeader *) conn->
- received_buf)->size)))
- conn->msg_complete = GNUNET_YES;
+ if ((client->received_pos >= sizeof (struct GNUNET_MessageHeader)) &&
+ (client->received_pos >=
+ ntohs (((const struct GNUNET_MessageHeader *) client->received_buf)->
+ size)))
+ client->msg_complete = GNUNET_YES;
}
/**
* Callback function for data received from the network. Note that
- * both "available" and "errCode" would be 0 if the read simply timed out.
+ * both @a available and @a errCode would be 0 if the read simply timed out.
*
* @param cls closure
* @param buf pointer to received data
- * @param available number of bytes availabe in "buf",
+ * @param available number of bytes availabe in @a buf,
* possibly 0 (on errors)
* @param addr address of the sender
- * @param addrlen size of addr
+ * @param addrlen size of @a addr
* @param errCode value of errno (on errors receiving)
*/
static void
receive_helper (void *cls,
const void *buf,
size_t available,
- const struct sockaddr *addr, socklen_t addrlen, int errCode)
+ const struct sockaddr *addr,
+ socklen_t addrlen,
+ int errCode)
{
- struct GNUNET_CLIENT_Connection *conn = cls;
+ struct GNUNET_CLIENT_Connection *client = 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;
-
- if ((available == 0) || (conn->sock == NULL) || (errCode != 0))
+ GNUNET_assert (GNUNET_NO == client->msg_complete);
+ GNUNET_assert (GNUNET_YES == client->in_receive);
+ client->in_receive = GNUNET_NO;
+ if ( (0 == available) ||
+ (NULL == client->connection) ||
+ (0 != errCode) )
+ {
+ /* signal timeout! */
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Timeout in receive_helper, available %u, client->connection %s, errCode `%s'\n",
+ (unsigned int) available,
+ NULL == client->connection ? "NULL" : "non-NULL",
+ STRERROR (errCode));
+ /* remember failure */
+ client->in_receive = GNUNET_SYSERR;
+ if (NULL != (receive_handler = client->receiver_handler))
{
- /* signal timeout! */
- if (conn->receiver_handler != NULL)
- {
- conn->receiver_handler (conn->receiver_handler_cls, NULL);
- conn->receiver_handler = NULL;
- }
- return;
+ receive_handler_cls = client->receiver_handler_cls;
+ client->receiver_handler = NULL;
+ receive_handler (receive_handler_cls,
+ NULL);
}
-
+ return;
+ }
/* FIXME: optimize for common fast case where buf contains the
- entire message and we need no copying... */
-
+ * entire message and we need no copying... */
/* slow path: append to array */
- if (conn->received_size < conn->received_pos + available)
- GNUNET_array_grow (conn->received_buf,
- conn->received_size, conn->received_pos + available);
- memcpy (&conn->received_buf[conn->received_pos], buf, available);
- conn->received_pos += available;
- check_complete (conn);
+ if (client->received_size < client->received_pos + available)
+ GNUNET_array_grow (client->received_buf, client->received_size,
+ client->received_pos + available);
+ memcpy (&client->received_buf[client->received_pos], buf, available);
+ client->received_pos += available;
+ check_complete (client);
/* check for timeout */
- remaining = GNUNET_TIME_absolute_get_remaining (conn->receive_timeout);
- if (remaining.value == 0)
+ remaining = GNUNET_TIME_absolute_get_remaining (client->receive_timeout);
+ if (0 == remaining.rel_value_us)
+ {
+ /* signal timeout! */
+ if (NULL != (receive_handler = client->receiver_handler))
{
- /* signal timeout! */
- conn->receiver_handler (conn->receiver_handler_cls, NULL);
- return;
+ client->receiver_handler = NULL;
+ receive_handler (client->receiver_handler_cls, NULL);
}
+ return;
+ }
/* back to receive -- either for more data or to call callback! */
- GNUNET_CLIENT_receive (conn,
- conn->receiver_handler,
- conn->receiver_handler_cls, remaining);
+ GNUNET_CLIENT_receive (client, client->receiver_handler,
+ client->receiver_handler_cls, remaining);
}
/**
* 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;
- 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;
+ struct GNUNET_CLIENT_Connection *client = cls;
+ GNUNET_CLIENT_MessageHandler handler = client->receiver_handler;
+ const struct GNUNET_MessageHeader *cmsg =
+ (const struct GNUNET_MessageHeader *) client->received_buf;
+ void *handler_cls = client->receiver_handler_cls;
uint16_t msize = ntohs (cmsg->size);
- char mbuf[msize];
- struct GNUNET_MessageHeader *msg = (struct GNUNET_MessageHeader*) mbuf;
+ char mbuf[msize] GNUNET_ALIGN;
+ struct GNUNET_MessageHeader *msg = (struct GNUNET_MessageHeader *) mbuf;
- GNUNET_assert (GNUNET_YES == sock->msg_complete);
- sock->receiver_task = GNUNET_SCHEDULER_NO_TASK;
- GNUNET_assert (sock->received_pos >= msize);
+ client->receive_task = NULL;
+ if ( (GNUNET_SYSERR == client->in_receive) &&
+ (GNUNET_YES != client->msg_complete) )
+ {
+ /* Connection failure, signal to caller! */
+ client->receiver_handler = NULL;
+ if (NULL != handler)
+ handler (handler_cls,
+ NULL);
+ return;
+ }
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Received message of type %u and size %u from %s service.\n",
+ ntohs (cmsg->type),
+ msize,
+ client->service_name);
+ GNUNET_assert (GNUNET_YES == client->msg_complete);
+ GNUNET_assert (client->received_pos >= msize);
memcpy (msg, cmsg, msize);
- memmove (sock->received_buf,
- &sock->received_buf[msize], sock->received_pos - msize);
- sock->received_pos -= msize;
- sock->msg_complete = GNUNET_NO;
- sock->receiver_handler = NULL;
- check_complete (sock);
- if (handler != NULL)
- handler (cls, msg);
+ memmove (client->received_buf, &client->received_buf[msize],
+ client->received_pos - msize);
+ client->received_pos -= msize;
+ client->msg_complete = GNUNET_NO;
+ client->receiver_handler = NULL;
+ check_complete (client);
+ if (NULL != handler)
+ handler (handler_cls, msg);
}
/**
* Read from the service.
*
- * @param sched scheduler to use
- * @param sock the service
+ * @param client the service
* @param handler function to call with the message
- * @param cls closure for handler
+ * @param handler_cls closure for @a handler
* @param timeout how long to wait until timing out
*/
void
-GNUNET_CLIENT_receive (struct GNUNET_CLIENT_Connection *sock,
+GNUNET_CLIENT_receive (struct GNUNET_CLIENT_Connection *client,
GNUNET_CLIENT_MessageHandler handler,
- void *cls, struct GNUNET_TIME_Relative timeout)
+ void *handler_cls,
+ struct GNUNET_TIME_Relative timeout)
{
- if (sock->sock == NULL)
- {
- /* already disconnected, fail instantly! */
- GNUNET_break (0); /* this should not happen in well-written code! */
- handler (cls, NULL);
- return;
- }
- GNUNET_assert (sock->receiver_task ==
- GNUNET_SCHEDULER_NO_TASK);
- sock->receiver_handler = handler;
- sock->receiver_handler_cls = 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);
- else
- sock->receiver_task = GNUNET_CONNECTION_receive (sock->sock,
- GNUNET_SERVER_MAX_MESSAGE_SIZE,
- timeout,
- &receive_helper, sock);
+ if (NULL == client->connection)
+ {
+ /* already disconnected, fail instantly! */
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "Client API violation for service `%s'\n",
+ client->service_name);
+ GNUNET_break (0); /* this should not happen in well-written code! */
+ if (NULL != handler)
+ handler (handler_cls,
+ NULL);
+ return;
+ }
+ client->receiver_handler = handler;
+ client->receiver_handler_cls = handler_cls;
+ client->receive_timeout = GNUNET_TIME_relative_to_absolute (timeout);
+ if ( (GNUNET_YES == client->msg_complete) ||
+ (GNUNET_SYSERR == client->in_receive) )
+ {
+ GNUNET_assert (NULL == client->receive_task);
+ client->receive_task = GNUNET_SCHEDULER_add_now (&receive_task, client);
+ return;
+ }
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "calling GNUNET_CONNECTION_receive\n");
+ GNUNET_assert (GNUNET_NO == client->in_receive);
+ client->in_receive = GNUNET_YES;
+ GNUNET_CONNECTION_receive (client->connection,
+ GNUNET_SERVER_MAX_MESSAGE_SIZE - 1,
+ timeout,
+ &receive_helper,
+ client);
}
-static size_t
-write_shutdown (void *cls, size_t size, void *buf)
+/**
+ * Handle for a test to check if a service is running.
+ */
+struct GNUNET_CLIENT_TestHandle
{
- struct GNUNET_MessageHeader *msg;
+ /**
+ * Function to call with the result of the test.
+ */
+ GNUNET_CLIENT_TestResultCallback cb;
- 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);
-}
+ /**
+ * Closure for @e cb.
+ */
+ void *cb_cls;
+
+ /**
+ * Client connection we are using for the test, if any.
+ */
+ struct GNUNET_CLIENT_Connection *client;
+
+ /**
+ * Handle for the transmission request, if any.
+ */
+ struct GNUNET_CLIENT_TransmitHandle *th;
+
+ /**
+ * Deadline for calling @e cb.
+ */
+ struct GNUNET_TIME_Absolute test_deadline;
+
+ /**
+ * ID of task used for asynchronous operations.
+ */
+ struct GNUNET_SCHEDULER_Task * task;
+
+ /**
+ * Final result to report back (once known).
+ */
+ int result;
+};
/**
- * Request that the service should shutdown.
- * Afterwards, the connection should be disconnected.
+ * Abort testing for service.
*
- * @param sched scheduler to use
- * @param sock the socket connected to the service
+ * @param th test handle
*/
void
-GNUNET_CLIENT_service_shutdown (struct GNUNET_CLIENT_Connection *sock)
+GNUNET_CLIENT_service_test_cancel (struct GNUNET_CLIENT_TestHandle *th)
{
- GNUNET_CONNECTION_notify_transmit_ready (sock->sock,
- sizeof (struct GNUNET_MessageHeader),
- GNUNET_TIME_UNIT_FOREVER_REL,
- &write_shutdown, NULL);
+ if (NULL != th->th)
+ {
+ GNUNET_CLIENT_notify_transmit_ready_cancel (th->th);
+ th->th = NULL;
+ }
+ if (NULL != th->client)
+ {
+ GNUNET_CLIENT_disconnect (th->client);
+ th->client = NULL;
+ }
+ if (NULL != th->task)
+ {
+ GNUNET_SCHEDULER_cancel (th->task);
+ th->task = NULL;
+ }
+ GNUNET_free (th);
}
/**
- * Report service unavailable.
+ * Task that reports back the result by calling the callback
+ * and then cleans up.
+ *
+ * @param cls the `struct GNUNET_CLIENT_TestHandle`
+ * @param tc scheduler context
*/
static void
-service_test_error (struct GNUNET_SCHEDULER_Handle *s,
- GNUNET_SCHEDULER_Task task, void *task_cls)
+report_result (void *cls,
+ const struct GNUNET_SCHEDULER_TaskContext *tc)
{
- GNUNET_SCHEDULER_add_continuation (s,
- GNUNET_YES,
- task,
- task_cls,
- GNUNET_SCHEDULER_REASON_TIMEOUT);
+ struct GNUNET_CLIENT_TestHandle *th = cls;
+
+ th->task = NULL;
+ th->cb (th->cb_cls, th->result);
+ GNUNET_CLIENT_service_test_cancel (th);
+}
+
+
+/**
+ * Report service test result asynchronously back to callback.
+ *
+ * @param th test handle with the result and the callback
+ * @param result result to report
+ */
+static void
+service_test_report (struct GNUNET_CLIENT_TestHandle *th,
+ int result)
+{
+ th->result = result;
+ th->task = GNUNET_SCHEDULER_add_now (&report_result,
+ th);
}
/**
* Receive confirmation from test, service is up.
*
- * @param cls closure
+ * @param cls closure with the `struct GNUNET_CLIENT_TestHandle`
* @param msg message received, NULL on timeout or fatal error
*/
static void
-confirm_handler (void *cls, const struct GNUNET_MessageHeader *msg)
+confirm_handler (void *cls,
+ const struct GNUNET_MessageHeader *msg)
{
- struct GNUNET_CLIENT_Connection *conn = cls;
+ struct GNUNET_CLIENT_TestHandle *th = cls;
+
/* We may want to consider looking at the reply in more
- detail in the future, for example, is this the
- correct service? FIXME! */
- if (msg != NULL)
- {
-#if DEBUG_CLIENT
- 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,
- conn->test_cb_cls,
- GNUNET_SCHEDULER_REASON_PREREQ_DONE);
- }
+ * detail in the future, for example, is this the
+ * correct service? FIXME! */
+ if (NULL != msg)
+ {
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Received confirmation that service is running.\n");
+ service_test_report (th, GNUNET_YES);
+ }
else
- {
- service_test_error (conn->sched, conn->test_cb, conn->test_cb_cls);
- }
- GNUNET_CLIENT_disconnect (conn);
+ {
+ service_test_report (th, GNUNET_NO);
+ }
}
+/**
+ * Send the 'TEST' message to the service. If successful, prepare to
+ * receive the reply.
+ *
+ * @param cls the `struct GNUNET_CLIENT_TestHandle` of the test
+ * @param size number of bytes available in @a buf
+ * @param buf where to write the message
+ * @return number of bytes written to @a buf
+ */
static size_t
write_test (void *cls, size_t size, void *buf)
{
+ struct GNUNET_CLIENT_TestHandle *th = cls;
struct GNUNET_MessageHeader *msg;
+ th->th = NULL;
if (size < sizeof (struct GNUNET_MessageHeader))
- {
-#if DEBUG_CLIENT
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- _("Failure to transmit TEST request.\n"));
-#endif
- return 0; /* client disconnected */
- }
-#if DEBUG_CLIENT
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, _("Transmitting TEST request.\n"));
-#endif
+ {
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Failed to transmit TEST request.\n");
+ service_test_report (th, GNUNET_NO);
+ return 0; /* client disconnected */
+ }
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Transmitting `%s' request.\n",
+ "TEST");
msg = (struct GNUNET_MessageHeader *) buf;
msg->type = htons (GNUNET_MESSAGE_TYPE_TEST);
msg->size = htons (sizeof (struct GNUNET_MessageHeader));
+ GNUNET_CLIENT_receive (th->client,
+ &confirm_handler, th,
+ GNUNET_TIME_absolute_get_remaining
+ (th->test_deadline));
return sizeof (struct GNUNET_MessageHeader);
}
/**
- * Wait until the service is running.
+ * Test if the service is running. If we are given a UNIXPATH or a
+ * local address, we do this NOT by trying to connect to the service,
+ * but by trying to BIND to the same port. If the BIND fails, we know
+ * 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 task to run if service is running
- * (reason will be "PREREQ_DONE" (service running)
- * or "TIMEOUT" (service not known to be running))
- * @param task_cls closure for task
+ * @param timeout how long to wait at most
+ * @param cb function to call with the result
+ * @param cb_cls closure for @a cb
+ * @return handle to cancel the test
*/
-void
-GNUNET_CLIENT_service_test (struct GNUNET_SCHEDULER_Handle *sched,
- const char *service,
+struct GNUNET_CLIENT_TestHandle *
+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_CLIENT_TestResultCallback cb,
+ void *cb_cls)
{
- struct GNUNET_CLIENT_Connection *conn;
+ struct GNUNET_CLIENT_TestHandle *th;
+ char *hostname;
+ unsigned long long port;
+ struct GNUNET_NETWORK_Handle *sock;
+
+ th = GNUNET_new (struct GNUNET_CLIENT_TestHandle);
+ th->cb = cb;
+ th->cb_cls = cb_cls;
+ th->test_deadline = GNUNET_TIME_relative_to_absolute (timeout);
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Testing if service `%s' is running.\n",
+ service);
+#ifdef AF_UNIX
+ {
+ /* probe UNIX support */
+ struct sockaddr_un s_un;
+ char *unixpath;
+ int abstract;
-#if DEBUG_CLIENT
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Testing if service `%s' is running.\n", service);
+ unixpath = NULL;
+ if ((GNUNET_OK ==
+ GNUNET_CONFIGURATION_get_value_filename (cfg,
+ service,
+ "UNIXPATH",
+ &unixpath)) &&
+ (0 < strlen (unixpath))) /* We have a non-NULL unixpath, does that mean it's valid? */
+ {
+ if (strlen (unixpath) >= sizeof (s_un.sun_path))
+ {
+ LOG (GNUNET_ERROR_TYPE_WARNING,
+ _("UNIXPATH `%s' too long, maximum length is %llu\n"),
+ unixpath,
+ (unsigned long long) sizeof (s_un.sun_path));
+ unixpath = GNUNET_NETWORK_shorten_unixpath (unixpath);
+ LOG (GNUNET_ERROR_TYPE_INFO,
+ _("Using `%s' instead\n"), unixpath);
+ }
+ }
+#ifdef LINUX
+ abstract = GNUNET_CONFIGURATION_get_value_yesno (cfg,
+ "TESTING",
+ "USE_ABSTRACT_SOCKETS");
+#else
+ abstract = GNUNET_NO;
#endif
- conn = GNUNET_CLIENT_connect (sched, service, cfg);
- if (conn == NULL)
+ if ((NULL != unixpath) && (GNUNET_YES != abstract))
{
- 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);
- return;
+ if (GNUNET_SYSERR == GNUNET_DISK_directory_create_for_file (unixpath))
+ GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_WARNING,
+ "mkdir", unixpath);
}
- 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))
+ if (NULL != unixpath)
+ {
+ sock = GNUNET_NETWORK_socket_create (PF_UNIX, SOCK_STREAM, 0);
+ if (NULL != sock)
+ {
+ memset (&s_un, 0, sizeof (s_un));
+ s_un.sun_family = AF_UNIX;
+ strncpy (s_un.sun_path, unixpath, sizeof (s_un.sun_path) - 1);
+ if (GNUNET_YES == abstract)
+ s_un.sun_path[0] = '\0';
+#if HAVE_SOCKADDR_IN_SIN_LEN
+ s_un.sun_len = (u_char) sizeof (struct sockaddr_un);
+#endif
+ if (GNUNET_OK !=
+ GNUNET_NETWORK_socket_bind (sock, (const struct sockaddr *) &s_un,
+ sizeof (struct sockaddr_un)))
+ {
+ /* failed to bind => service must be running */
+ GNUNET_free (unixpath);
+ (void) GNUNET_NETWORK_socket_close (sock);
+ service_test_report (th, GNUNET_YES);
+ return th;
+ }
+ (void) GNUNET_NETWORK_socket_close (sock);
+ /* let's try IP */
+ }
+ }
+ GNUNET_free_non_null (unixpath);
+ }
+#endif
+
+ hostname = NULL;
+ if ((GNUNET_OK !=
+ GNUNET_CONFIGURATION_get_value_number (cfg, service, "PORT", &port)) ||
+ (port > 65535) ||
+ (GNUNET_OK !=
+ GNUNET_CONFIGURATION_get_value_string (cfg, service, "HOSTNAME",
+ &hostname)))
+ {
+ /* UNIXPATH failed (if possible) AND IP failed => error */
+ service_test_report (th, GNUNET_SYSERR);
+ return th;
+ }
+
+ if (0 == strcmp ("localhost", hostname)
+#if !LINUX
+ && 0
+#endif
+ )
+ {
+ /* can test using 'bind' */
+ struct sockaddr_in s_in;
+
+ memset (&s_in, 0, sizeof (s_in));
+#if HAVE_SOCKADDR_IN_SIN_LEN
+ s_in.sin_len = sizeof (struct sockaddr_in);
+#endif
+ s_in.sin_family = AF_INET;
+ s_in.sin_port = htons (port);
+
+ sock = GNUNET_NETWORK_socket_create (AF_INET, SOCK_STREAM, 0);
+ if (NULL != sock)
+ {
+ if (GNUNET_OK !=
+ GNUNET_NETWORK_socket_bind (sock, (const struct sockaddr *) &s_in,
+ sizeof (s_in)))
+ {
+ /* failed to bind => service must be running */
+ GNUNET_free (hostname);
+ (void) GNUNET_NETWORK_socket_close (sock);
+ service_test_report (th, GNUNET_YES);
+ return th;
+ }
+ (void) GNUNET_NETWORK_socket_close (sock);
+ }
+ }
+
+ if (0 == strcmp ("ip6-localhost", hostname)
+#if !LINUX
+ && 0
+#endif
+ )
+ {
+ /* can test using 'bind' */
+ struct sockaddr_in6 s_in6;
+
+ memset (&s_in6, 0, sizeof (s_in6));
+#if HAVE_SOCKADDR_IN_SIN_LEN
+ s_in6.sin6_len = sizeof (struct sockaddr_in6);
+#endif
+ s_in6.sin6_family = AF_INET6;
+ s_in6.sin6_port = htons (port);
+
+ sock = GNUNET_NETWORK_socket_create (AF_INET6, SOCK_STREAM, 0);
+ if (NULL != sock)
+ {
+ if (GNUNET_OK !=
+ GNUNET_NETWORK_socket_bind (sock, (const struct sockaddr *) &s_in6,
+ sizeof (s_in6)))
+ {
+ /* failed to bind => service must be running */
+ GNUNET_free (hostname);
+ (void) GNUNET_NETWORK_socket_close (sock);
+ service_test_report (th, GNUNET_YES);
+ return th;
+ }
+ (void) GNUNET_NETWORK_socket_close (sock);
+ }
+ }
+
+ if (((0 == strcmp ("localhost", hostname)) ||
+ (0 == strcmp ("ip6-localhost", hostname)))
+#if !LINUX
+ && 0
+#endif
+ )
+ {
+ /* all binds succeeded => claim service not running right now */
+ GNUNET_free_non_null (hostname);
+ service_test_report (th, GNUNET_NO);
+ return th;
+ }
+ GNUNET_free_non_null (hostname);
+
+ /* non-localhost, try 'connect' method */
+ th->client = GNUNET_CLIENT_connect (service, cfg);
+ if (NULL == th->client)
+ {
+ LOG (GNUNET_ERROR_TYPE_INFO,
+ _("Could not connect to service `%s', configuration broken.\n"),
+ service);
+ service_test_report (th, GNUNET_SYSERR);
+ return th;
+ }
+ th->th = GNUNET_CLIENT_notify_transmit_ready (th->client,
+ sizeof (struct GNUNET_MessageHeader),
+ timeout, GNUNET_YES,
+ &write_test, th);
+ if (NULL == th->th)
+ {
+ LOG (GNUNET_ERROR_TYPE_WARNING,
+ _("Failure to transmit request to service `%s'\n"), service);
+ service_test_report (th, GNUNET_SYSERR);
+ return th;
+ }
+ return th;
+}
+
+
+/**
+ * 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 @a 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;
+ struct GNUNET_TIME_Relative delay;
+
+ th->reconnect_task = NULL;
+ if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
+ {
+ /* give up, was shutdown */
+ th->client->th = NULL;
+ th->notify (th->notify_cls, 0, NULL);
+ GNUNET_free (th);
+ return;
+ }
+ th->client->connection =
+ do_connect (th->client->service_name,
+ th->client->cfg,
+ th->client->attempts++);
+ th->client->first_message = GNUNET_YES;
+ if (NULL == th->client->connection)
+ {
+ /* could happen if we're out of sockets */
+ delay = GNUNET_TIME_relative_min (GNUNET_TIME_absolute_get_remaining (th->timeout),
+ th->client->back_off);
+ th->client->back_off = GNUNET_TIME_STD_BACKOFF (th->client->back_off);
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Transmission failed %u times, trying again in %s.\n",
+ MAX_ATTEMPTS - th->attempts_left,
+ GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_YES));
+ GNUNET_assert (NULL == th->th);
+ GNUNET_assert (NULL == th->reconnect_task);
+ th->reconnect_task =
+ GNUNET_SCHEDULER_add_delayed (delay, &client_delayed_retry, th);
+ return;
+ }
+ th->th =
+ GNUNET_CONNECTION_notify_transmit_ready (th->client->connection, th->size,
+ GNUNET_TIME_absolute_get_remaining
+ (th->timeout), &client_notify,
+ th);
+ if (NULL == th->th)
+ {
+ GNUNET_break (0);
+ th->client->th = NULL;
+ th->notify (th->notify_cls, 0, NULL);
+ GNUNET_free (th);
+ 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 @a buf
+ */
+static size_t
+client_notify (void *cls,
+ size_t size,
+ void *buf)
+{
+ struct GNUNET_CLIENT_TransmitHandle *th = cls;
+ struct GNUNET_CLIENT_Connection *client = th->client;
+ size_t ret;
+ struct GNUNET_TIME_Relative delay;
+
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "client_notify is running\n");
+ th->th = NULL;
+ client->th = NULL;
+ if (NULL == buf)
+ {
+ delay = GNUNET_TIME_absolute_get_remaining (th->timeout);
+ delay.rel_value_us /= 2;
+ if ( (GNUNET_YES != th->auto_retry) ||
+ (0 == --th->attempts_left) ||
+ (delay.rel_value_us < 1)||
+ (0 != (GNUNET_SCHEDULER_get_reason() & GNUNET_SCHEDULER_REASON_SHUTDOWN)))
+ {
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Transmission failed %u times, giving up.\n",
+ MAX_ATTEMPTS - th->attempts_left);
+ GNUNET_break (0 ==
+ th->notify (th->notify_cls, 0, NULL));
+ GNUNET_free (th);
+ return 0;
+ }
+ /* auto-retry */
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Failed to connect to `%s', automatically trying again.\n",
+ client->service_name);
+ if (GNUNET_YES == client->in_receive)
{
- 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);
- return;
+ GNUNET_CONNECTION_receive_cancel (client->connection);
+ client->in_receive = GNUNET_NO;
}
- GNUNET_CLIENT_receive (conn, &confirm_handler, conn, timeout);
+ GNUNET_CONNECTION_destroy (client->connection);
+ client->connection = NULL;
+ delay = GNUNET_TIME_relative_min (delay, client->back_off);
+ client->back_off =
+ GNUNET_TIME_relative_min (GNUNET_TIME_relative_multiply
+ (client->back_off, 2),
+ GNUNET_TIME_UNIT_SECONDS);
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Transmission failed %u times, trying again in %s.\n",
+ MAX_ATTEMPTS - th->attempts_left,
+ GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_YES));
+ client->th = th;
+ GNUNET_assert (NULL == th->reconnect_task);
+ GNUNET_assert (NULL == th->th);
+ th->reconnect_task =
+ GNUNET_SCHEDULER_add_delayed (delay, &client_delayed_retry, th);
+ return 0;
+ }
+ GNUNET_assert (size >= th->size);
+ ret = th->notify (th->notify_cls, size, buf);
+ GNUNET_free (th);
+ if (sizeof (struct GNUNET_MessageHeader) <= ret)
+ {
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Transmitting message of type %u and size %u to %s service.\n",
+ ntohs (((struct GNUNET_MessageHeader *) buf)->type),
+ ntohs (((struct GNUNET_MessageHeader *) buf)->size),
+ client->service_name);
+ }
+ return ret;
}
/**
* Ask the client to call us once the specified number of bytes
- * are free in the transmission buffer. May call the notify
- * method immediately if enough space is available.
+ * are free in the transmission buffer. Will never call the @a notify
+ * callback in this task, but always first go into the scheduler.
*
* @param client connection to the service
* @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
+ * @param notify_cls closure for @a 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_NETWORK_TransmitHandle *
-GNUNET_CLIENT_notify_transmit_ready (struct GNUNET_CLIENT_Connection *sock,
+struct GNUNET_CLIENT_TransmitHandle *
+GNUNET_CLIENT_notify_transmit_ready (struct GNUNET_CLIENT_Connection *client,
size_t size,
struct GNUNET_TIME_Relative timeout,
- GNUNET_NETWORK_TransmitReadyNotify
- notify, void *notify_cls)
+ int auto_retry,
+ GNUNET_CONNECTION_TransmitReadyNotify notify,
+ void *notify_cls)
+{
+ struct GNUNET_CLIENT_TransmitHandle *th;
+
+ if (NULL != client->th)
+ {
+ /* If this breaks, you most likley called this function twice without waiting
+ * for completion or canceling the request */
+ GNUNET_assert (0);
+ return NULL;
+ }
+ th = GNUNET_new (struct GNUNET_CLIENT_TransmitHandle);
+ th->client = client;
+ th->size = size;
+ th->timeout = GNUNET_TIME_relative_to_absolute (timeout);
+ /* always auto-retry on first message to service */
+ th->auto_retry = (GNUNET_YES == client->first_message) ? GNUNET_YES : auto_retry;
+ client->first_message = GNUNET_NO;
+ th->notify = notify;
+ th->notify_cls = notify_cls;
+ th->attempts_left = MAX_ATTEMPTS;
+ client->th = th;
+ if (NULL == client->connection)
+ {
+ GNUNET_assert (NULL == th->th);
+ GNUNET_assert (NULL == th->reconnect_task);
+ th->reconnect_task =
+ GNUNET_SCHEDULER_add_delayed (client->back_off,
+ &client_delayed_retry,
+ th);
+ }
+ else
+ {
+ th->th = GNUNET_CONNECTION_notify_transmit_ready (client->connection,
+ size,
+ timeout,
+ &client_notify,
+ th);
+ if (NULL == th->th)
+ {
+ GNUNET_break (0);
+ GNUNET_free (th);
+ client->th = NULL;
+ return NULL;
+ }
+ }
+ return th;
+}
+
+
+/**
+ * Cancel a request for notification.
+ *
+ * @param th handle from the original request.
+ */
+void
+GNUNET_CLIENT_notify_transmit_ready_cancel (struct GNUNET_CLIENT_TransmitHandle *th)
{
- return GNUNET_CONNECTION_notify_transmit_ready (sock->sock,
- size,
- timeout, notify, notify_cls);
+ if (NULL != th->reconnect_task)
+ {
+ GNUNET_assert (NULL == th->th);
+ GNUNET_SCHEDULER_cancel (th->reconnect_task);
+ th->reconnect_task = NULL;
+ }
+ else
+ {
+ GNUNET_assert (NULL != th->th);
+ GNUNET_CONNECTION_notify_transmit_ready_cancel (th->th);
+ }
+ th->client->th = NULL;
+ GNUNET_free (th);
+}
+
+
+/**
+ * Function called to notify a client about the socket
+ * begin ready to queue the message. @a buf will be
+ * NULL and @a size zero if the socket was closed for
+ * writing in the meantime.
+ *
+ * @param cls closure of type `struct TransmitGetResponseContext *`
+ * @param size number of bytes available in @a buf
+ * @param buf where the callee should write the message
+ * @return number of bytes written to @a buf
+ */
+static size_t
+transmit_for_response (void *cls,
+ size_t size,
+ void *buf)
+{
+ struct TransmitGetResponseContext *tc = cls;
+ uint16_t msize;
+
+ tc->client->tag = NULL;
+ msize = ntohs (tc->hdr->size);
+ if (NULL == buf)
+ {
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Could not submit request, not expecting to receive a response.\n");
+ if (NULL != tc->rn)
+ tc->rn (tc->rn_cls, NULL);
+ GNUNET_free (tc);
+ return 0;
+ }
+ GNUNET_assert (size >= msize);
+ memcpy (buf, tc->hdr, msize);
+ GNUNET_CLIENT_receive (tc->client,
+ tc->rn,
+ tc->rn_cls,
+ GNUNET_TIME_absolute_get_remaining (tc->timeout));
+ GNUNET_free (tc);
+ return msize;
+}
+
+
+/**
+ * Convenience API that combines sending a request
+ * to the service and waiting for a response.
+ * If either operation times out, the callback
+ * will be called with a "NULL" response (in which
+ * case the connection should probably be destroyed).
+ *
+ * @param client connection to use
+ * @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 @a rn
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR if a request
+ * is already pending
+ */
+int
+GNUNET_CLIENT_transmit_and_get_response (struct GNUNET_CLIENT_Connection *client,
+ const struct GNUNET_MessageHeader *hdr,
+ struct GNUNET_TIME_Relative timeout,
+ int auto_retry,
+ GNUNET_CLIENT_MessageHandler rn,
+ void *rn_cls)
+{
+ struct TransmitGetResponseContext *tc;
+ uint16_t msize;
+
+ if (NULL != client->th)
+ return GNUNET_SYSERR;
+ GNUNET_assert (NULL == client->tag);
+ msize = ntohs (hdr->size);
+ tc = GNUNET_malloc (sizeof (struct TransmitGetResponseContext) + msize);
+ tc->client = client;
+ 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;
+ if (NULL ==
+ GNUNET_CLIENT_notify_transmit_ready (client, msize, timeout, auto_retry,
+ &transmit_for_response, tc))
+ {
+ GNUNET_break (0);
+ GNUNET_free (tc);
+ return GNUNET_SYSERR;
+ }
+ client->tag = tc;
+ return GNUNET_OK;
}