2 This file is part of GNUnet.
3 (C) 2011 Christian Grothoff (and other contributing authors)
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13 General Public License for more details.
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22 * @file fs/gnunet-service-fs_lc.c
23 * @brief API to handle 'connected peers'
24 * @author Christian Grothoff
28 #include "gnunet-service-fs_lc.h"
32 * Doubly-linked list of requests we are performing
33 * on behalf of the same client.
39 * This is a doubly-linked list.
41 struct ClientRequest *next;
44 * This is a doubly-linked list.
46 struct ClientRequest *prev;
49 * Request this entry represents.
51 struct GSF_PendingRequest *pr;
54 * Client list this request belongs to.
56 struct GSF_LocalClient *lc;
63 * Replies to be transmitted to the client. The actual
64 * response message is allocated after this struct.
69 * This is a doubly-linked list.
71 struct ClientResponse *next;
74 * This is a doubly-linked list.
76 struct ClientResponse *prev;
79 * Client list entry this response belongs to.
81 struct GSF_LocalClient *lc;
84 * Number of bytes in the response.
94 struct GSF_LocalClient
98 * We keep clients in a DLL.
100 struct GSF_LocalClient *next;
103 * We keep clients in a DLL.
105 struct GSF_LocalClient *prev;
110 struct GNUNET_SERVER_Client *client;
113 * Head of list of requests performed on behalf
114 * of this client right now.
116 struct ClientRequest *cr_head;
119 * Tail of list of requests performed on behalf
120 * of this client right now.
122 struct ClientRequest *cr_tail;
125 * Head of linked list of responses.
127 struct ClientResponse *res_head;
130 * Tail of linked list of responses.
132 struct ClientResponse *res_tail;
135 * Context for sending replies.
137 struct GNUNET_CONNECTION_TransmitHandle *th;
143 * Head of linked list of our local clients.
145 static struct GSF_LocalClient *client_head;
149 * Head of linked list of our local clients.
151 static struct GSF_LocalClient *client_tail;
155 * Look up a local client record or create one if it
158 * @param client handle of the client
159 * @return handle to local client entry
161 struct GSF_LocalClient *
162 GSF_local_client_lookup_ (struct GNUNET_SERVER_Client *client)
164 struct GSF_LocalClient *pos;
167 while ( (pos != NULL) &&
168 (pos->client != client) )
172 pos = GNUNET_malloc (sizeof (struct GSF_LocalClient));
173 pos->client = client;
174 GNUNET_CONTAINER_DLL_insert (client_head,
182 * Handle a reply to a pending request. Also called if a request
183 * expires (then with data == NULL). The handler may be called
184 * many times (depending on the request type), but will not be
185 * called during or after a call to GSF_pending_request_cancel
186 * and will also not be called anymore after a call signalling
189 * @param cls user-specified closure
190 * @param pr handle to the original pending request
191 * @param data response data, NULL on request expiration
192 * @param data_len number of bytes in data
193 * @param more GNUNET_YES if the request remains active (may call
194 * this function again), GNUNET_NO if the request is
195 * finished (client must not call GSF_pending_request_cancel_)
198 client_response_handler (void *cls,
199 struct GSF_PendingRequest *pr,
204 struct ClientRequest *cr = cls;
208 /* ugh, request 'timed out' -- how can this be? */
210 GNUNET_assert (GNUNET_NO == more);
213 /* FIXME: adapt old code below to new API! */
215 GNUNET_STATISTICS_update (stats,
216 gettext_noop ("# replies received for local clients"),
219 cl = pr->client_request_list->client_list;
220 msize = sizeof (struct PutMessage) + prq->size;
221 creply = GNUNET_malloc (msize + sizeof (struct ClientResponseMessage));
222 creply->msize = msize;
223 creply->client_list = cl;
224 GNUNET_CONTAINER_DLL_insert_after (cl->res_head,
228 pm = (struct PutMessage*) &creply[1];
229 pm->header.type = htons (GNUNET_MESSAGE_TYPE_FS_PUT);
230 pm->header.size = htons (msize);
231 pm->type = htonl (prq->type);
232 pm->expiration = GNUNET_TIME_absolute_hton (prq->expiration);
233 memcpy (&pm[1], prq->data, prq->size);
237 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
238 "Transmitting result for query `%s' to client\n",
241 cl->th = GNUNET_SERVER_notify_transmit_ready (cl->client,
243 GNUNET_TIME_UNIT_FOREVER_REL,
247 GNUNET_break (cl->th != NULL);
250 prq->finished = GNUNET_YES;
251 destroy_pending_request (pr);
259 * Handle START_SEARCH-message (search request from local client).
261 * @param client identification of the client
262 * @param message the actual message
263 * @return pending request handle for the request, NULL on error
265 struct GSF_PendingRequest *
266 GSF_local_client_start_search_handler_ (struct GNUNET_SERVER_Client *client,
267 const struct GNUNET_MessageHeader *message)
269 static GNUNET_HashCode all_zeros;
270 const struct SearchMessage *sm;
271 struct GSF_LocalClient *lc;
272 struct ClientRequest *cr;
273 struct GSF_PendingRequest *pr;
276 enum GNUNET_BLOCK_Type type;
277 enum GSF_PendingRequestOptions options;
279 msize = ntohs (message->size);
280 if ( (msize < sizeof (struct SearchMessage)) ||
281 (0 != (msize - sizeof (struct SearchMessage)) % sizeof (GNUNET_HashCode)) )
284 GNUNET_SERVER_receive_done (client,
288 GNUNET_STATISTICS_update (stats,
289 gettext_noop ("# client searches received"),
292 sc = (msize - sizeof (struct SearchMessage)) / sizeof (GNUNET_HashCode);
293 sm = (const struct SearchMessage*) message;
294 type = ntohl (sm->type);
296 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
297 "Received request for `%s' of type %u from local client\n",
298 GNUNET_h2s (&sm->query),
299 (unsigned int) type);
301 lc = GSF_local_client_lookup_ (client);
303 /* detect duplicate KBLOCK requests */
304 if ( (type == GNUNET_BLOCK_TYPE_FS_KBLOCK) ||
305 (type == GNUNET_BLOCK_TYPE_FS_NBLOCK) ||
306 (type == GNUNET_BLOCK_TYPE_ANY) )
309 while ( (cl != NULL) &&
310 ( (0 != memcmp (GSF_pending_request_get_query_ (cr->pr),
312 sizeof (GNUNET_HashCode))) ||
313 (GSF_pending_request_get_type_ (cr->pr) != type) ) )
318 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
319 "Have existing request, merging content-seen lists.\n");
321 GSF_pending_request_update_ (cr->pr,
324 GNUNET_STATISTICS_update (stats,
325 gettext_noop ("# client searches updated (merged content seen list)"),
328 GNUNET_SERVER_receive_done (client,
334 GNUNET_STATISTICS_update (stats,
335 gettext_noop ("# client searches active"),
338 cr = GNUNET_malloc (sizeof (struct ClientRequest));
340 GNUNET_CONTAINER_DLL_insert (lc->cr_head,
343 options = GSF_PRO_LOCAL_REQUEST;
344 if (0 != (1 & ntohl (sm->options)))
345 options |= GSF_PRO_LOCAL_ONLY;
346 cr->pr = GSF_pending_request_create_ (options,
349 (type == GNUNET_BLOCK_TYPE_SBLOCK)
350 ? &sm->target /* namespace */
352 (0 != memcmp (&sm->target,
354 sizeof (GNUNET_HashCode)))
358 ntohl (sm->anonymity_level),
361 &client_response_handler,
368 * Transmit the given message by copying it to the target buffer
369 * "buf". "buf" will be NULL and "size" zero if the socket was closed
370 * for writing in the meantime. In that case, do nothing
371 * (the disconnect or shutdown handler will take care of the rest).
372 * If we were able to transmit messages and there are still more
373 * pending, ask core again for further calls to this function.
375 * @param cls closure, pointer to the 'struct GSF_LocalClient'
376 * @param size number of bytes available in buf
377 * @param buf where the callee should write the message
378 * @return number of bytes written to buf
381 transmit_to_client (void *cls,
385 struct GSF_LocalClient *lc = cls;
387 struct ClientResponse *res;
394 while ( (NULL != (res = lc->res_head) ) &&
395 (res->msize <= size) )
397 memcpy (&cbuf[msize], &res[1], res->msize);
400 GNUNET_CONTAINER_DLL_remove (cl->res_head,
406 lc->th = GNUNET_SERVER_notify_transmit_ready (lc->client,
408 GNUNET_TIME_UNIT_FOREVER_REL,
416 * Transmit a message to the given local client as soon as possible.
417 * If the client disconnects before transmission, the message is
420 * @param lc recipient
421 * @param msg message to transmit to client
424 GSF_local_client_transmit_ (struct GSF_LocalClient *lc,
425 const struct GNUNET_MessageHeader *msg)
427 struct ClientResponse *res;
430 msize = ntohs (msg->size);
431 res = GNUNET_malloc (sizeof (struct ClientResponse) + msize);
434 GNUNET_CONTAINER_DLL_insert_tail (lc->res_head,
438 lc->tc = GNUNET_CLIENT_notify_transmit_ready (lc->client,
440 GNUNET_TIME_UNIT_FOREVER_REL,
448 * A client disconnected from us. Tear down the local client
452 * @param client handle of the client
455 GSF_client_disconnect_handler_ (void *cls,
456 const struct GNUNET_SERVER_Client *client)
458 struct GSF_LocalClient *pos;
459 struct DisconnectCallback *dc;
460 struct ClientRequest *cr;
461 struct ClientResponse *res;
464 while ( (pos != NULL) &&
465 (pos->client != client) )
469 while (NULL != (cr = pos->cr_head))
471 GNUNET_CONTAINER_DLL_remove (pos->cr_head,
474 GSF_pending_request_cancel_ (cr->pr);
477 while (NULL != (res = pos->res_head))
479 GNUNET_CONTAINER_DLL_remove (pos->res_head,
486 GNUNET_CONNECTION_notify_transmit_ready_cancel (pos->th);
489 GSF_handle_local_client_disconnect_ (pos);
494 /* end of gnunet-service-fs_lc.c */