GNUnet  0.11.x
gnunet-service-fs_cadet_client.c
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1 /*
2  This file is part of GNUnet.
3  Copyright (C) 2012, 2013 GNUnet e.V.
4 
5  GNUnet is free software: you can redistribute it and/or modify it
6  under the terms of the GNU Affero General Public License as published
7  by the Free Software Foundation, either version 3 of the License,
8  or (at your option) any later version.
9 
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  Affero General Public License for more details.
14 
15  You should have received a copy of the GNU Affero General Public License
16  along with this program. If not, see <http://www.gnu.org/licenses/>.
17 
18  SPDX-License-Identifier: AGPL3.0-or-later
19  */
20 
30 #include "platform.h"
31 #include "gnunet_constants.h"
32 #include "gnunet_util_lib.h"
33 #include "gnunet_cadet_service.h"
34 #include "gnunet_protocols.h"
35 #include "gnunet_applications.h"
36 #include "gnunet-service-fs.h"
39 
40 
44 #define CLIENT_RETRY_TIMEOUT \
45  GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 30)
46 
47 
51 struct CadetHandle;
52 
53 
58 {
63 
68 
72  struct CadetHandle *mh;
73 
78 
82  void *proc_cls;
83 
88 
93 
99 };
100 
101 
106 {
111 
116 
122 
127 
131  struct GNUNET_PeerIdentity target;
132 
139 
146 };
147 
148 
153 
159 
160 
161 /* ********************* client-side code ************************* */
162 
163 
169 static void
170 transmit_pending (void *cls);
171 
172 
182 static int
183 move_to_pending (void *cls, const struct GNUNET_HashCode *key, void *value)
184 {
185  struct CadetHandle *mh = cls;
186  struct GSF_CadetRequest *sr = value;
187 
188  GNUNET_assert (
189  GNUNET_YES ==
193  return GNUNET_YES;
194 }
195 
196 
205 static int
206 check_reply (void *cls, const struct CadetReplyMessage *srm)
207 {
208  /* We check later... */
209  return GNUNET_OK;
210 }
211 
212 
218 static void
219 reset_cadet_task (void *cls);
220 
221 
228 static void
230 {
231  if (NULL != mh->reset_task)
234 }
235 
236 
241 {
245  const void *data;
246 
251 
255  size_t data_size;
256 
261 
265  int found;
266 };
267 
268 
278 static int
279 process_reply (void *cls, const struct GNUNET_HashCode *key, void *value)
280 {
281  struct HandleReplyClosure *hrc = cls;
282  struct GSF_CadetRequest *sr = value;
283 
284  sr->proc (sr->proc_cls,
285  hrc->type,
286  hrc->expiration,
287  hrc->data_size,
288  hrc->data);
289  sr->proc = NULL;
291  hrc->found = GNUNET_YES;
292  return GNUNET_YES;
293 }
294 
295 
306 static int
307 free_waiting_entry (void *cls, const struct GNUNET_HashCode *key, void *value)
308 {
309  struct GSF_CadetRequest *sr = value;
310 
312  return GNUNET_YES;
313 }
314 
315 
323 static void
324 handle_reply (void *cls, const struct CadetReplyMessage *srm)
325 {
326  struct CadetHandle *mh = cls;
327  struct HandleReplyClosure hrc;
328  uint16_t msize;
329  enum GNUNET_BLOCK_Type type;
330  struct GNUNET_HashCode query;
331 
332  msize = ntohs (srm->header.size) - sizeof(struct CadetReplyMessage);
333  type = (enum GNUNET_BLOCK_Type) ntohl (srm->type);
334  if (GNUNET_YES !=
335  GNUNET_BLOCK_get_key (GSF_block_ctx, type, &srm[1], msize, &query))
336  {
337  GNUNET_break_op (0);
338  GNUNET_log (
340  "Received bogus reply of type %u with %u bytes via cadet from peer %s\n",
341  type,
342  msize,
343  GNUNET_i2s (&mh->target));
344  reset_cadet_async (mh);
345  return;
346  }
348  "Received reply `%s' via cadet from peer %s\n",
349  GNUNET_h2s (&query),
350  GNUNET_i2s (&mh->target));
353  gettext_noop ("# replies received via cadet"),
354  1,
355  GNUNET_NO);
356  hrc.data = &srm[1];
357  hrc.data_size = msize;
359  hrc.type = type;
360  hrc.found = GNUNET_NO;
362  &query,
363  &process_reply,
364  &hrc);
365  if (GNUNET_NO == hrc.found)
366  {
368  gettext_noop (
369  "# replies received via cadet dropped"),
370  1,
371  GNUNET_NO);
372  }
373 }
374 
375 
383 static void
384 disconnect_cb (void *cls, const struct GNUNET_CADET_Channel *channel)
385 {
386  struct CadetHandle *mh = cls;
387  struct GSF_CadetRequest *sr;
388 
389  if (NULL == mh->channel)
390  return; /* being destroyed elsewhere */
391  GNUNET_assert (channel == mh->channel);
392  mh->channel = NULL;
393  while (NULL != (sr = mh->pending_head))
395  /* first remove `mh` from the `cadet_map`, so that if the
396  callback from `free_waiting_entry()` happens to re-issue
397  the request, we don't immediately have it back in the
398  `waiting_map`. */
400  &mh->target,
401  mh));
404  mh);
405  if (NULL != mh->timeout_task)
407  if (NULL != mh->reset_task)
411  GNUNET_free (mh);
412 }
413 
414 
429 static void
430 window_change_cb (void *cls,
431  const struct GNUNET_CADET_Channel *channel,
432  int window_size)
433 {
434  /* FIXME: for flow control, implement? */
435 #if 0
436  /* Something like this instead of the GNUNET_MQ_notify_sent() in
437  transmit_pending() might be good (once the window change CB works...) */
438  if (0 < window_size) /* test needed? */
440 #endif
441 }
442 
443 
449 static void
451 {
453  "Resetting cadet channel to %s\n",
454  GNUNET_i2s (&mh->target));
455  if (NULL != mh->channel)
456  {
458  mh->channel = NULL;
459  }
461  {
462  struct GNUNET_MQ_MessageHandler handlers[] =
463  { GNUNET_MQ_hd_var_size (reply,
465  struct CadetReplyMessage,
466  mh),
468  struct GNUNET_HashCode port;
469 
472  &port);
473  mh->channel = GNUNET_CADET_channel_create (cadet_handle,
474  mh,
475  &mh->target,
476  &port,
478  &disconnect_cb,
479  handlers);
480  }
481  transmit_pending (mh);
482 }
483 
484 
490 static void
491 cadet_timeout (void *cls)
492 {
493  struct CadetHandle *mh = cls;
494  struct GNUNET_CADET_Channel *tun;
495 
497  "Timeout on cadet channel to %s\n",
498  GNUNET_i2s (&mh->target));
499  mh->timeout_task = NULL;
500  tun = mh->channel;
501  mh->channel = NULL;
502  if (NULL != tun)
504 }
505 
506 
512 static void
513 reset_cadet_task (void *cls)
514 {
515  struct CadetHandle *mh = cls;
516 
517  mh->reset_task = NULL;
518  reset_cadet (mh);
519 }
520 
521 
527 static void
528 transmit_pending (void *cls)
529 {
530  struct CadetHandle *mh = cls;
532  struct GSF_CadetRequest *sr;
533  struct GNUNET_MQ_Envelope *env;
534  struct CadetQueryMessage *sqm;
535 
536  if ((0 != GNUNET_MQ_get_length (mq)) || (NULL == (sr = mh->pending_head)))
537  return;
540  mh->waiting_map,
541  &sr->query,
542  sr,
546  "Sending query for %s via cadet to %s\n",
547  GNUNET_h2s (&sr->query),
548  GNUNET_i2s (&mh->target));
554  sqm->type = htonl (sr->type);
555  sqm->query = sr->query;
557  GNUNET_MQ_send (mq, env);
558 }
559 
560 
566 static struct CadetHandle *
568 {
569  struct CadetHandle *mh;
570 
571  mh = GNUNET_CONTAINER_multipeermap_get (cadet_map, target);
572  if (NULL != mh)
573  {
574  if (NULL != mh->timeout_task)
575  {
577  mh->timeout_task = NULL;
578  }
579  return mh;
580  }
582  "Creating cadet channel to %s\n",
583  GNUNET_i2s (target));
584  mh = GNUNET_new (struct CadetHandle);
585  mh->reset_task =
588  mh->target = *target;
591  cadet_map,
592  &mh->target,
593  mh,
595  {
596  struct GNUNET_MQ_MessageHandler handlers[] =
597  { GNUNET_MQ_hd_var_size (reply,
599  struct CadetReplyMessage,
600  mh),
602  struct GNUNET_HashCode port;
603 
606  &port);
607  mh->channel = GNUNET_CADET_channel_create (cadet_handle,
608  mh,
609  &mh->target,
610  &port,
612  &disconnect_cb,
613  handlers);
614  }
615  return mh;
616 }
617 
618 
629 struct GSF_CadetRequest *
630 GSF_cadet_query (const struct GNUNET_PeerIdentity *target,
631  const struct GNUNET_HashCode *query,
632  enum GNUNET_BLOCK_Type type,
634  void *proc_cls)
635 {
636  struct CadetHandle *mh;
637  struct GSF_CadetRequest *sr;
638 
640  "Preparing to send query for %s via cadet to %s\n",
641  GNUNET_h2s (query),
642  GNUNET_i2s (target));
643  mh = get_cadet (target);
644  sr = GNUNET_new (struct GSF_CadetRequest);
645  sr->mh = mh;
646  sr->proc = proc;
647  sr->proc_cls = proc_cls;
648  sr->type = type;
649  sr->query = *query;
651  transmit_pending (mh);
652  return sr;
653 }
654 
655 
662 void
664 {
665  struct CadetHandle *mh = sr->mh;
667 
668  p = sr->proc;
669  sr->proc = NULL;
670  if (NULL != p)
671  {
672  /* signal failure / cancellation to callback */
674  }
676  "Cancelled query for %s via cadet to %s\n",
677  GNUNET_h2s (&sr->query),
678  GNUNET_i2s (&sr->mh->target));
679  if (GNUNET_YES == sr->was_transmitted)
680  GNUNET_assert (
681  GNUNET_OK ==
683  else
685  GNUNET_free (sr);
687  (NULL == mh->pending_head))
689  &cadet_timeout,
690  mh);
691 }
692 
693 
702 int
704  const struct GNUNET_PeerIdentity *key,
705  void *value)
706 {
707  struct CadetHandle *mh = value;
708 
710  "Timeout on cadet channel to %s\n",
711  GNUNET_i2s (&mh->target));
712  if (NULL != mh->channel)
713  {
714  struct GNUNET_CADET_Channel *channel = mh->channel;
715 
716  mh->channel = NULL;
718  }
719  if (NULL != mh->reset_task)
720  {
722  mh->reset_task = NULL;
723  }
724  return GNUNET_YES;
725 }
726 
727 
728 /* end of gnunet-service-fs_cadet_client.c */
#define GNUNET_CONTAINER_DLL_remove(head, tail, element)
Remove an element from a DLL.
static void window_change_cb(void *cls, const struct GNUNET_CADET_Channel *channel, int window_size)
Function called whenever an MQ-channel&#39;s transmission window size changes.
#define GNUNET_MESSAGE_TYPE_FS_CADET_REPLY
P2P answer for content (one FS to another via a cadet).
struct GNUNET_TIME_Absolute expiration
Expiration time for the block.
struct GNUNET_CONTAINER_MultiPeerMap * cadet_map
Map from peer identities to &#39;struct CadetHandles&#39; with cadet channels to those peers.
Query from one peer, asking the other for CHK-data.
int found
Did we have a matching query?
static int check_reply(void *cls, const struct CadetReplyMessage *srm)
Functions with this signature are called whenever a complete reply is received.
struct GNUNET_TIME_Absolute GNUNET_TIME_absolute_ntoh(struct GNUNET_TIME_AbsoluteNBO a)
Convert absolute time from network byte order.
Definition: time.c:673
#define GNUNET_TIME_UNIT_ZERO_ABS
Absolute time zero.
struct GSF_CadetRequest * GSF_cadet_query(const struct GNUNET_PeerIdentity *target, const struct GNUNET_HashCode *query, enum GNUNET_BLOCK_Type type, GSF_CadetReplyProcessor proc, void *proc_cls)
Look for a block by directly contacting a particular peer.
unsigned int GNUNET_CONTAINER_multihashmap_size(const struct GNUNET_CONTAINER_MultiHashMap *map)
Get the number of key-value pairs in the map.
#define GNUNET_CONTAINER_DLL_insert(head, tail, element)
Insert an element at the head of a DLL.
Any type of block, used as a wildcard when searching.
Opaque handle to the service.
Definition: cadet_api.c:38
GNUNET_BLOCK_Type
Blocks in the datastore and the datacache must have a unique type.
static void disconnect_cb(void *cls, const struct GNUNET_CADET_Channel *channel)
Function called by cadet when a client disconnects.
#define GNUNET_assert(cond)
Use this for fatal errors that cannot be handled.
Handle for a cadet to another peer.
#define GNUNET_TIME_UNIT_SECONDS
One second.
struct GNUNET_MessageHeader header
Type is GNUNET_MESSAGE_TYPE_FS_CADET_REPLY.
void GNUNET_MQ_env_set_options(struct GNUNET_MQ_Envelope *env, enum GNUNET_MQ_PriorityPreferences pp)
Set application-specific options for this envelope.
Definition: mq.c:1005
static int process_reply(void *cls, const struct GNUNET_HashCode *key, void *value)
Iterator called on each entry in a waiting map to process a result.
#define GNUNET_MQ_msg(mvar, type)
Allocate a GNUNET_MQ_Envelope.
Definition: gnunet_mq_lib.h:67
static int move_to_pending(void *cls, const struct GNUNET_HashCode *key, void *value)
Iterator called on each entry in a waiting map to move it back to the pending list.
uint32_t type
Block type must be DBLOCK or IBLOCK.
struct GNUNET_STATISTICS_Handle * GSF_stats
Handle for reporting statistics.
int GNUNET_CONTAINER_multipeermap_remove(struct GNUNET_CONTAINER_MultiPeerMap *map, const struct GNUNET_PeerIdentity *key, const void *value)
Remove the given key-value pair from the map.
#define GNUNET_NO
Definition: gnunet_common.h:78
shared data structures of gnunet-service-fs.c
Opaque handle to a channel.
Definition: cadet_api.c:80
const char * GNUNET_h2s(const struct GNUNET_HashCode *hc)
Convert a hash value to a string (for printing debug messages).
#define GNUNET_OK
Named constants for return values.
Definition: gnunet_common.h:75
#define GNUNET_new(type)
Allocate a struct or union of the given type.
static void handle_reply(void *cls, const struct CadetReplyMessage *srm)
Functions with this signature are called whenever a complete reply is received.
uint16_t size
The length of the struct (in bytes, including the length field itself), in big-endian format...
void GNUNET_STATISTICS_update(struct GNUNET_STATISTICS_Handle *handle, const char *name, int64_t delta, int make_persistent)
Set statistic value for the peer.
Internal representation of the hash map.
struct GNUNET_HashCode query
Query to transmit to the other peer.
int GNUNET_BLOCK_get_key(struct GNUNET_BLOCK_Context *ctx, enum GNUNET_BLOCK_Type type, const void *block, size_t block_size, struct GNUNET_HashCode *key)
Function called to obtain the key for a block.
Definition: block.c:378
static void reset_cadet_async(struct CadetHandle *mh)
We had a serious error, tear down and re-create cadet from scratch, but do so asynchronously.
const void * data
Reply payload.
struct GNUNET_SCHEDULER_Task * GNUNET_SCHEDULER_add_delayed(struct GNUNET_TIME_Relative delay, GNUNET_SCHEDULER_TaskCallback task, void *task_cls)
Schedule a new task to be run with a specified delay.
Definition: scheduler.c:1253
Flag to indicate that high bandwidth is desired.
#define CLIENT_RETRY_TIMEOUT
After how long do we reset connections without replies?
static struct GNUNET_OS_Process * p
Helper process we started.
Definition: gnunet-qr.c:59
struct GNUNET_HashCode query
Query hash from CHK (hash of encrypted block).
void GNUNET_MQ_notify_sent(struct GNUNET_MQ_Envelope *ev, GNUNET_SCHEDULER_TaskCallback cb, void *cb_cls)
Call a callback once the envelope has been sent, that is, sending it can not be canceled anymore...
Definition: mq.c:774
static char * value
Value of the record to add/remove.
int was_transmitted
Did we transmit this request already? GNUNET_YES if we are in the &#39;waiting_map&#39;, GNUNET_NO if we are ...
#define GNUNET_MQ_hd_var_size(name, code, str, ctx)
#define GNUNET_break_op(cond)
Use this for assertion violations caused by other peers (i.e.
void GNUNET_CRYPTO_hash(const void *block, size_t size, struct GNUNET_HashCode *ret)
Compute hash of a given block.
Definition: crypto_hash.c:48
unsigned int GNUNET_MQ_get_length(struct GNUNET_MQ_Handle *mq)
Obtain the current length of the message queue.
Definition: mq.c:335
void GNUNET_CONTAINER_multihashmap_destroy(struct GNUNET_CONTAINER_MultiHashMap *map)
Destroy a hash map.
struct GSF_CadetRequest * next
DLL.
struct GNUNET_SCHEDULER_Task * GNUNET_SCHEDULER_add_now(GNUNET_SCHEDULER_TaskCallback task, void *task_cls)
Schedule a new task to be run as soon as possible.
Definition: scheduler.c:1280
struct GSF_CadetRequest * prev
DLL.
struct GNUNET_BLOCK_Context * GSF_block_ctx
Our block context.
static void reset_cadet_task(void *cls)
Task called when it is time to reset an cadet.
non-anonymous file-transfer
int GNUNET_CONTAINER_multihashmap_remove(struct GNUNET_CONTAINER_MultiHashMap *map, const struct GNUNET_HashCode *key, const void *value)
Remove the given key-value pair from the map.
void * proc_cls
Closure for proc.
Closure for handle_reply().
Internal representation of the hash map.
struct GNUNET_PeerIdentity target
Which peer does this cadet go to?
A 512-bit hashcode.
static char * expiration
Credential TTL.
Definition: gnunet-abd.c:96
Message handler for a specific message type.
struct GNUNET_SCHEDULER_Task * timeout_task
Task to kill inactive cadets (we keep them around for a few seconds to give the application a chance ...
struct GNUNET_SCHEDULER_Task * reset_task
Task to reset cadets that had errors (asynchronously, as we may not be able to do it immediately duri...
There must only be one value per key; storing a value should fail if a value under the same key alrea...
Handle for a request that is going out via cadet API.
struct GNUNET_HashCode key
The key used in the DHT.
struct GNUNET_MQ_Envelope * env
Definition: 005.c:1
struct GNUNET_TIME_AbsoluteNBO expiration
Expiration time for the block.
indexing for the file-sharing service
int GNUNET_CONTAINER_multihashmap_put(struct GNUNET_CONTAINER_MultiHashMap *map, const struct GNUNET_HashCode *key, void *value, enum GNUNET_CONTAINER_MultiHashMapOption opt)
Store a key-value pair in the map.
GSF_CadetReplyProcessor proc
Function to call with the result.
Allow multiple values with the same key.
Handle to a message queue.
Definition: mq.c:85
int GNUNET_CONTAINER_multipeermap_put(struct GNUNET_CONTAINER_MultiPeerMap *map, const struct GNUNET_PeerIdentity *key, void *value, enum GNUNET_CONTAINER_MultiHashMapOption opt)
Store a key-value pair in the map.
The identity of the host (wraps the signing key of the peer).
void GNUNET_CADET_receive_done(struct GNUNET_CADET_Channel *channel)
Send an ack on the channel to confirm the processing of a message.
Definition: cadet_api.c:954
int GNUNET_CONTAINER_multihashmap_get_multiple(struct GNUNET_CONTAINER_MultiHashMap *map, const struct GNUNET_HashCode *key, GNUNET_CONTAINER_MulitHashMapIteratorCallback it, void *it_cls)
Iterate over all entries in the map that match a particular key.
struct GNUNET_CADET_Channel * GNUNET_CADET_channel_create(struct GNUNET_CADET_Handle *h, void *channel_cls, const struct GNUNET_PeerIdentity *destination, const struct GNUNET_HashCode *port, GNUNET_CADET_WindowSizeEventHandler window_changes, GNUNET_CADET_DisconnectEventHandler disconnects, const struct GNUNET_MQ_MessageHandler *handlers)
Create a new channel towards a remote peer.
Definition: cadet_api.c:1068
struct GNUNET_CADET_Channel * channel
Channel to the other peer.
struct GSF_CadetRequest * pending_head
Head of DLL of pending requests on this cadet.
struct GSF_CadetRequest * pending_tail
Tail of DLL of pending requests on this cadet.
static void reset_cadet(struct CadetHandle *mh)
We had a serious error, tear down and re-create cadet from scratch.
void * GNUNET_CONTAINER_multipeermap_get(const struct GNUNET_CONTAINER_MultiPeerMap *map, const struct GNUNET_PeerIdentity *key)
Given a key find a value in the map matching the key.
struct GNUNET_MQ_Handle * mq
Definition: 003.c:5
#define GNUNET_MESSAGE_TYPE_FS_CADET_QUERY
P2P request for content (one FS to another via a cadet).
#define GNUNET_log(kind,...)
Entry in list of pending tasks.
Definition: scheduler.c:134
Flag to indicate that out-of-order delivery is OK.
static void cadet_timeout(void *cls)
Task called when it is time to destroy an inactive cadet channel.
static int free_waiting_entry(void *cls, const struct GNUNET_HashCode *key, void *value)
Iterator called on each entry in a waiting map to call the &#39;proc&#39; continuation and release associated...
struct GNUNET_CONTAINER_MultiHashMap * GNUNET_CONTAINER_multihashmap_create(unsigned int len, int do_not_copy_keys)
Create a multi hash map.
#define GNUNET_APPLICATION_PORT_FS_BLOCK_TRANSFER
Transfer of blocks for non-anonymmous file-sharing.
Flag to indicate that CORKing is acceptable.
Time for absolute times used by GNUnet, in microseconds.
#define GNUNET_YES
Definition: gnunet_common.h:77
void GNUNET_MQ_send(struct GNUNET_MQ_Handle *mq, struct GNUNET_MQ_Envelope *ev)
Send a message with the given message queue.
Definition: mq.c:353
uint32_t type
Block type must be DBLOCK or IBLOCK.
int GSF_cadet_release_clients(void *cls, const struct GNUNET_PeerIdentity *key, void *value)
Function called on each active cadets to shut them down.
static void transmit_pending(void *cls)
Transmit pending requests via the cadet.
struct GNUNET_CADET_Handle * cadet_handle
Cadet channel for creating outbound channels.
enum GNUNET_BLOCK_Type type
Type of the block.
struct CadetHandle * mh
Which cadet is this request associated with?
int GNUNET_CONTAINER_multihashmap_iterate(struct GNUNET_CONTAINER_MultiHashMap *map, GNUNET_CONTAINER_MulitHashMapIteratorCallback it, void *it_cls)
Iterate over all entries in the map.
size_t data_size
Number of bytes in data.
Reply to a CadetQueryMessage.
void GNUNET_CADET_channel_destroy(struct GNUNET_CADET_Channel *channel)
Destroy an existing channel.
Definition: cadet_api.c:903
const char * GNUNET_i2s(const struct GNUNET_PeerIdentity *pid)
Convert a peer identity to a string (for printing debug messages).
struct GNUNET_CONTAINER_MultiHashMap * waiting_map
Map from query to struct GSF_CadetRequests waiting for a reply.
enum GNUNET_BLOCK_Type type
Desired type for the reply.
#define GNUNET_MQ_handler_end()
End-marker for the handlers array.
void(* GSF_CadetReplyProcessor)(void *cls, enum GNUNET_BLOCK_Type type, struct GNUNET_TIME_Absolute expiration, size_t data_size, const void *data)
Function called with a reply from the cadet.
void GSF_cadet_query_cancel(struct GSF_CadetRequest *sr)
Cancel an active request; must not be called after &#39;proc&#39; was calld.
#define GNUNET_free(ptr)
Wrapper around free.
static struct CadetHandle * get_cadet(const struct GNUNET_PeerIdentity *target)
Get (or create) a cadet to talk to the given peer.
#define gettext_noop(String)
Definition: gettext.h:69
struct GNUNET_MQ_Handle * GNUNET_CADET_get_mq(const struct GNUNET_CADET_Channel *channel)
Obtain the message queue for a connected peer.
Definition: cadet_api.c:1119
void * GNUNET_SCHEDULER_cancel(struct GNUNET_SCHEDULER_Task *task)
Cancel the task with the specified identifier.
Definition: scheduler.c:966