2 This file is part of GNUnet.
3 (C) 2009 Christian Grothoff (and other contributing authors)
5 GNUnet is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 2, or (at your
8 option) any later version.
10 GNUnet is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
22 * @file util/server_tc.c
23 * @brief convenience functions for transmission of
24 * complex responses as a server
25 * @author Christian Grothoff
29 #include "gnunet_common.h"
30 #include "gnunet_connection_lib.h"
31 #include "gnunet_scheduler_lib.h"
32 #include "gnunet_server_lib.h"
33 #include "gnunet_time_lib.h"
38 * How much buffer space do we want to have at least
39 * before transmitting another increment?
41 #define MIN_BLOCK_SIZE 128
45 struct GNUNET_SERVER_TransmitContext
48 * Which client are we transmitting to?
50 struct GNUNET_SERVER_Client *client;
53 * Transmission buffer. (current offset for writing).
58 * Number of bytes in buf.
63 * Offset for writing in buf.
68 * Timeout for this request.
70 struct GNUNET_TIME_Absolute timeout;
75 * Helper function for incremental transmission of the response.
78 transmit_response (void *cls, size_t size, void *buf)
80 struct GNUNET_SERVER_TransmitContext *tc = cls;
84 GNUNET_SERVER_receive_done (tc->client, GNUNET_SYSERR);
85 GNUNET_SERVER_client_drop (tc->client);
86 GNUNET_free_non_null (tc->buf);
90 if (tc->total - tc->off > size)
93 msize = tc->total - tc->off;
94 memcpy (buf, &tc->buf[tc->off], msize);
96 if (tc->total == tc->off)
98 GNUNET_SERVER_receive_done (tc->client, GNUNET_OK);
99 GNUNET_SERVER_client_drop (tc->client);
100 GNUNET_free_non_null (tc->buf);
105 if (NULL == GNUNET_SERVER_notify_transmit_ready (tc->client,
108 tc->total - tc->off),
109 GNUNET_TIME_absolute_get_remaining
115 GNUNET_SERVER_receive_done (tc->client, GNUNET_SYSERR);
116 GNUNET_SERVER_client_drop (tc->client);
117 GNUNET_free_non_null (tc->buf);
126 * Create a new transmission context for the
129 * @param client client to create the context for.
130 * @return NULL on error
132 struct GNUNET_SERVER_TransmitContext *
133 GNUNET_SERVER_transmit_context_create (struct GNUNET_SERVER_Client *client)
135 struct GNUNET_SERVER_TransmitContext *tc;
137 GNUNET_assert (client != NULL);
138 tc = GNUNET_malloc (sizeof (struct GNUNET_SERVER_TransmitContext));
139 GNUNET_SERVER_client_keep (client);
146 * Append a message to the transmission context.
147 * All messages in the context will be sent by
148 * the transmit_context_run method.
150 * @param tc context to use
151 * @param data what to append to the result message
152 * @param length length of data
153 * @param type type of the message
156 GNUNET_SERVER_transmit_context_append_data (struct GNUNET_SERVER_TransmitContext
157 *tc, const void *data, size_t length,
160 struct GNUNET_MessageHeader *msg;
163 GNUNET_assert (length < GNUNET_SERVER_MAX_MESSAGE_SIZE);
164 size = length + sizeof (struct GNUNET_MessageHeader);
165 GNUNET_assert (size > length);
166 tc->buf = GNUNET_realloc (tc->buf, tc->total + size);
167 msg = (struct GNUNET_MessageHeader *) &tc->buf[tc->total];
169 msg->size = htons (size);
170 msg->type = htons (type);
171 memcpy (&msg[1], data, length);
176 * Append a message to the transmission context.
177 * All messages in the context will be sent by
178 * the transmit_context_run method.
180 * @param tc context to use
181 * @param msg message to append
184 GNUNET_SERVER_transmit_context_append_message(struct GNUNET_SERVER_TransmitContext
185 *tc, const struct GNUNET_MessageHeader *msg)
187 struct GNUNET_MessageHeader *m;
190 size = ntohs (msg->size);
191 tc->buf = GNUNET_realloc (tc->buf, tc->total + size);
192 m = (struct GNUNET_MessageHeader *) &tc->buf[tc->total];
194 memcpy (m, msg, size);
199 * Execute a transmission context. If there is
200 * an error in the transmission, the receive_done
201 * method will be called with an error code (GNUNET_SYSERR),
202 * otherwise with GNUNET_OK.
204 * @param tc transmission context to use
205 * @param timeout when to time out and abort the transmission
208 GNUNET_SERVER_transmit_context_run (struct GNUNET_SERVER_TransmitContext *tc,
209 struct GNUNET_TIME_Relative timeout)
211 tc->timeout = GNUNET_TIME_relative_to_absolute (timeout);
213 GNUNET_SERVER_notify_transmit_ready (tc->client,
214 GNUNET_MIN (MIN_BLOCK_SIZE,
216 &transmit_response, tc))
219 GNUNET_SERVER_receive_done (tc->client, GNUNET_SYSERR);
220 GNUNET_SERVER_client_drop (tc->client);
221 GNUNET_free_non_null (tc->buf);
226 /* end of server_tc.c */