GNUnet  0.10.x
nc.c
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1 /*
2  This file is part of GNUnet.
3  Copyright (C) 2010, 2016 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 
28 #include "platform.h"
29 #include "gnunet_util_lib.h"
30 
31 #define LOG(kind,...) GNUNET_log_from (kind, "util-nc", __VA_ARGS__)
32 
33 
38 {
39 
44 
49 
54 
60 
65 
66 };
67 
68 
78 {
79 
84 
89 
93  unsigned int queue_length;
94 
95 };
96 
97 
103 static void
104 handle_mq_destroy (void *cls)
105 {
106  struct SubscriberList *pos = cls;
107  struct GNUNET_NotificationContext *nc = pos->nc;
108 
110  nc->subscribers_tail,
111  pos);
112  GNUNET_free (pos);
113 }
114 
115 
126 {
128 
131  return nc;
132 }
133 
134 
140 void
142 {
143  struct SubscriberList *pos;
144 
145  while (NULL != (pos = nc->subscribers_head))
146  {
148  nc->subscribers_tail,
149  pos);
151  GNUNET_free (pos);
152  }
153  GNUNET_free (nc);
154 }
155 
156 
163 void
165  struct GNUNET_MQ_Handle *mq)
166 {
167  struct SubscriberList *cl;
168 
169  for (cl = nc->subscribers_head; NULL != cl; cl = cl->next)
170  if (cl->mq == mq)
171  return; /* already present */
172  cl = GNUNET_new (struct SubscriberList);
174  nc->subscribers_tail,
175  cl);
176  cl->nc = nc;
177  cl->mq = mq;
178  cl->mq_nh = GNUNET_MQ_destroy_notify (cl->mq,
180  cl);
181 }
182 
183 
191 void
193  const struct GNUNET_MessageHeader *msg,
194  int can_drop)
195 {
196  struct SubscriberList *pos;
197  struct GNUNET_MQ_Envelope *env;
198 
199  for (pos = nc->subscribers_head; NULL != pos; pos = pos->next)
200  {
201  if ( (GNUNET_YES == can_drop) &&
202  (GNUNET_MQ_get_length (pos->mq) > nc->queue_length) )
203  continue;
204  env = GNUNET_MQ_msg_copy (msg);
205  GNUNET_MQ_send (pos->mq,
206  env);
207  }
208 }
209 
210 
217 unsigned int
219 {
220  unsigned int num;
221  struct SubscriberList *pos;
222 
223  num = 0;
224  for (pos = nc->subscribers_head; NULL != pos; pos = pos->next)
225  num++;
226  return num;
227 }
228 
229 /* end of nc.c */
#define GNUNET_CONTAINER_DLL_remove(head, tail, element)
Remove an element from a DLL.
Handle we return for callbacks registered to be notified when GNUNET_MQ_destroy() is called on a queu...
Definition: mq.c:789
struct GNUNET_MQ_Envelope * GNUNET_MQ_msg_copy(const struct GNUNET_MessageHeader *hdr)
Create a new envelope by copying an existing message.
Definition: mq.c:653
The notification context is the key datastructure for a convenience API used for transmission of noti...
Definition: nc.c:77
struct GNUNET_MessageHeader * msg
Definition: 005.c:2
struct GNUNET_MQ_DestroyNotificationHandle * GNUNET_MQ_destroy_notify(struct GNUNET_MQ_Handle *mq, GNUNET_SCHEDULER_TaskCallback cb, void *cb_cls)
Register function to be called whenever mq is being destroyed.
Definition: mq.c:1109
#define GNUNET_CONTAINER_DLL_insert(head, tail, element)
Insert an element at the head of a DLL.
struct GNUNET_NotificationContext * nc
Overall context this subscriber belongs to.
Definition: nc.c:53
struct SubscriberList * prev
This is a doubly linked list.
Definition: nc.c:48
unsigned int queue_length
Maximum number of optional messages to queue per subscriber.
Definition: nc.c:93
#define GNUNET_new(type)
Allocate a struct or union of the given type.
struct SubscriberList * next
This is a doubly linked list.
Definition: nc.c:43
static void handle_mq_destroy(void *cls)
Subscriber has disconnected, clean up.
Definition: nc.c:104
void GNUNET_notification_context_add(struct GNUNET_NotificationContext *nc, struct GNUNET_MQ_Handle *mq)
Add a subscriber to the notification context.
Definition: nc.c:164
struct SubscriberList * subscribers_tail
Tail of list of subscribers receiving notifications.
Definition: nc.c:88
unsigned int GNUNET_MQ_get_length(struct GNUNET_MQ_Handle *mq)
Obtain the current length of the message queue.
Definition: mq.c:335
unsigned int GNUNET_notification_context_get_size(struct GNUNET_NotificationContext *nc)
Return active number of subscribers in this context.
Definition: nc.c:218
Lists of subscribers we manage for notifications.
Definition: nc.c:37
struct SubscriberList * subscribers_head
Head of list of subscribers receiving notifications.
Definition: nc.c:83
struct GNUNET_MQ_Envelope * env
Definition: 005.c:1
struct GNUNET_NotificationContext * GNUNET_notification_context_create(unsigned int queue_length)
Create a new notification context.
Definition: nc.c:125
Handle to a message queue.
Definition: mq.c:85
void GNUNET_notification_context_broadcast(struct GNUNET_NotificationContext *nc, const struct GNUNET_MessageHeader *msg, int can_drop)
Send a message to all subscribers of this context.
Definition: nc.c:192
struct GNUNET_MQ_Handle * mq
Message queue for the subscriber.
Definition: nc.c:64
void GNUNET_MQ_destroy_notify_cancel(struct GNUNET_MQ_DestroyNotificationHandle *dnh)
Cancel registration from GNUNET_MQ_destroy_notify().
Definition: mq.c:1130
Header for all communications.
#define GNUNET_YES
Definition: gnunet_common.h:80
void GNUNET_notification_context_destroy(struct GNUNET_NotificationContext *nc)
Destroy the context, force disconnect for all subscribers.
Definition: nc.c:141
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
struct GNUNET_MQ_DestroyNotificationHandle * mq_nh
Handle where we registered with mq to be told about the MQ&#39;s destruction.
Definition: nc.c:59
#define GNUNET_free(ptr)
Wrapper around free.