2 This file is part of GNUnet.
3 (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2009 Christian Grothoff (and other contributing authors)
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13 General Public License for more details.
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22 * @file include/gnunet_client_lib.h
23 * @brief functions related to accessing services
24 * @author Christian Grothoff
27 #ifndef GNUNET_CLIENT_LIB_H
28 #define GNUNET_CLIENT_LIB_H
33 #if 0 /* keep Emacsens' auto-indent happy */
38 #include "gnunet_common.h"
39 #include "gnunet_configuration_lib.h"
40 #include "gnunet_connection_lib.h"
41 #include "gnunet_scheduler_lib.h"
42 #include "gnunet_time_lib.h"
45 * Opaque handle for a connection to a service.
47 struct GNUNET_CLIENT_Connection;
50 * Get a connection with a service.
52 * @param service_name name of the service
53 * @param cfg configuration to use
54 * @return NULL on error (service unknown to configuration)
56 struct GNUNET_CLIENT_Connection *
57 GNUNET_CLIENT_connect (const char *service_name,
58 const struct GNUNET_CONFIGURATION_Handle *cfg);
62 * Destroy connection with the service. This will automatically
63 * cancel any pending "receive" request (however, the handler will
64 * *NOT* be called, not even with a NULL message). Any pending
65 * transmission request will also be cancelled UNLESS the callback for
66 * the transmission request has already been called, in which case the
67 * transmission 'finish_pending_write' argument determines whether or
68 * not the write is guaranteed to complete before the socket is fully
69 * destroyed (unless, of course, there is an error with the server in
70 * which case the message may still be lost).
72 * @param sock handle to the service connection
73 * @param finish_pending_write should a transmission already passed to the
74 * handle be completed?
77 GNUNET_CLIENT_disconnect (struct GNUNET_CLIENT_Connection *sock,
78 int finish_pending_write);
82 * Type of a function to call when we receive a message
86 * @param msg message received, NULL on timeout or fatal error
88 typedef void (*GNUNET_CLIENT_MessageHandler) (void *cls,
89 const struct GNUNET_MessageHeader
94 * Type of a function to call when we have finished shutting
95 * down a service, or failed.
98 * @param reason what is the result of the shutdown
99 * GNUNET_NO on shutdown (not running)
100 * GNUNET_YES on running
101 * GNUNET_SYSERR on failure to transmit message
103 typedef void (*GNUNET_CLIENT_ShutdownTask) (void *cls, int reason);
107 * Read from the service.
109 * @param sock the service
110 * @param handler function to call with the message
111 * @param handler_cls closure for handler
112 * @param timeout how long to wait until timing out
115 GNUNET_CLIENT_receive (struct GNUNET_CLIENT_Connection *sock,
116 GNUNET_CLIENT_MessageHandler handler, void *handler_cls,
117 struct GNUNET_TIME_Relative timeout);
121 * Transmit handle for client connections.
123 struct GNUNET_CLIENT_TransmitHandle;
127 * Ask the client to call us once the specified number of bytes
128 * are free in the transmission buffer. May call the notify
129 * method immediately if enough space is available.
131 * @param sock connection to the service
132 * @param size number of bytes to send
133 * @param timeout after how long should we give up (and call
134 * notify with buf NULL and size 0)?
135 * @param auto_retry if the connection to the service dies, should we
136 * automatically re-connect and retry (within the timeout period)
137 * or should we immediately fail in this case? Pass GNUNET_YES
138 * if the caller does not care about temporary connection errors,
139 * for example because the protocol is stateless
140 * @param notify function to call
141 * @param notify_cls closure for notify
142 * @return NULL if someone else is already waiting to be notified
143 * non-NULL if the notify callback was queued (can be used to cancel
144 * using GNUNET_CONNECTION_notify_transmit_ready_cancel)
146 struct GNUNET_CLIENT_TransmitHandle *
147 GNUNET_CLIENT_notify_transmit_ready (struct GNUNET_CLIENT_Connection *sock,
149 struct GNUNET_TIME_Relative timeout,
151 GNUNET_CONNECTION_TransmitReadyNotify
152 notify, void *notify_cls);
156 * Cancel a request for notification.
158 * @param th handle from the original request.
161 GNUNET_CLIENT_notify_transmit_ready_cancel (struct GNUNET_CLIENT_TransmitHandle
166 * Convenience API that combines sending a request
167 * to the service and waiting for a response.
168 * If either operation times out, the callback
169 * will be called with a "NULL" response (in which
170 * case the connection should probably be destroyed).
172 * @param sock connection to use
173 * @param hdr message to transmit
174 * @param timeout when to give up (for both transmission
175 * and for waiting for a response)
176 * @param auto_retry if the connection to the service dies, should we
177 * automatically re-connect and retry (within the timeout period)
178 * or should we immediately fail in this case? Pass GNUNET_YES
179 * if the caller does not care about temporary connection errors,
180 * for example because the protocol is stateless
181 * @param rn function to call with the response
182 * @param rn_cls closure for rn
183 * @return GNUNET_OK on success, GNUNET_SYSERR if a request
187 GNUNET_CLIENT_transmit_and_get_response (struct GNUNET_CLIENT_Connection *sock,
188 const struct GNUNET_MessageHeader *hdr,
189 struct GNUNET_TIME_Relative timeout,
191 GNUNET_CLIENT_MessageHandler rn,
196 * Wait until the service is running.
198 * @param service name of the service to wait for
199 * @param cfg configuration to use
200 * @param timeout how long to wait at most in ms
201 * @param task task to run if service is running
202 * (reason will be "PREREQ_DONE" (service running)
203 * or "TIMEOUT" (service not known to be running))
204 * @param task_cls closure for task
207 GNUNET_CLIENT_service_test (const char *service,
208 const struct GNUNET_CONFIGURATION_Handle *cfg,
209 struct GNUNET_TIME_Relative timeout,
210 GNUNET_SCHEDULER_Task task, void *task_cls);
213 #if 0 /* keep Emacsens' auto-indent happy */
220 /* ifndef GNUNET_CLIENT_LIB_H */
222 /* end of gnunet_client_lib.h */