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 
42 
47 
52 
58 
63 };
64 
65 
79 
84 
88  unsigned int queue_length;
89 };
90 
91 
97 static void
99 {
100  struct SubscriberList *pos = cls;
101  struct GNUNET_NotificationContext *nc = pos->nc;
102 
104  nc->subscribers_tail,
105  pos);
106  GNUNET_free(pos);
107 }
108 
109 
120 {
122 
125  return nc;
126 }
127 
128 
134 void
136 {
137  struct SubscriberList *pos;
138 
139  while (NULL != (pos = nc->subscribers_head))
140  {
142  nc->subscribers_tail,
143  pos);
145  GNUNET_free(pos);
146  }
147  GNUNET_free(nc);
148 }
149 
150 
157 void
159  struct GNUNET_MQ_Handle *mq)
160 {
161  struct SubscriberList *cl;
162 
163  for (cl = nc->subscribers_head; NULL != cl; cl = cl->next)
164  if (cl->mq == mq)
165  return;
166  /* already present */
167  cl = GNUNET_new(struct SubscriberList);
169  nc->subscribers_tail,
170  cl);
171  cl->nc = nc;
172  cl->mq = mq;
175  cl);
176 }
177 
178 
186 void
188  const struct GNUNET_MessageHeader *msg,
189  int can_drop)
190 {
191  struct SubscriberList *pos;
192  struct GNUNET_MQ_Envelope *env;
193 
194  for (pos = nc->subscribers_head; NULL != pos; pos = pos->next)
195  {
196  if ((GNUNET_YES == can_drop) &&
197  (GNUNET_MQ_get_length(pos->mq) > nc->queue_length))
198  continue;
199  env = GNUNET_MQ_msg_copy(msg);
200  GNUNET_MQ_send(pos->mq,
201  env);
202  }
203 }
204 
205 
212 unsigned int
214 {
215  unsigned int num;
216  struct SubscriberList *pos;
217 
218  num = 0;
219  for (pos = nc->subscribers_head; NULL != pos; pos = pos->next)
220  num++;
221  return num;
222 }
223 
224 /* 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:787
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:651
The notification context is the key datastructure for a convenience API used for transmission of noti...
Definition: nc.c:74
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:1106
#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:51
struct SubscriberList * prev
This is a doubly linked list.
Definition: nc.c:46
unsigned int queue_length
Maximum number of optional messages to queue per subscriber.
Definition: nc.c:88
#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:41
static void handle_mq_destroy(void *cls)
Subscriber has disconnected, clean up.
Definition: nc.c:98
void GNUNET_notification_context_add(struct GNUNET_NotificationContext *nc, struct GNUNET_MQ_Handle *mq)
Add a subscriber to the notification context.
Definition: nc.c:158
struct SubscriberList * subscribers_tail
Tail of list of subscribers receiving notifications.
Definition: nc.c:83
unsigned int GNUNET_MQ_get_length(struct GNUNET_MQ_Handle *mq)
Obtain the current length of the message queue.
Definition: mq.c:333
unsigned int GNUNET_notification_context_get_size(struct GNUNET_NotificationContext *nc)
Return active number of subscribers in this context.
Definition: nc.c:213
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:78
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:119
Handle to a message queue.
Definition: mq.c:84
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:187
struct GNUNET_MQ_Handle * mq
Message queue for the subscriber.
Definition: nc.c:62
void GNUNET_MQ_destroy_notify_cancel(struct GNUNET_MQ_DestroyNotificationHandle *dnh)
Cancel registration from GNUNET_MQ_destroy_notify().
Definition: mq.c:1127
Header for all communications.
#define GNUNET_YES
Definition: gnunet_common.h:77
void GNUNET_notification_context_destroy(struct GNUNET_NotificationContext *nc)
Destroy the context, force disconnect for all subscribers.
Definition: nc.c:135
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:351
struct GNUNET_MQ_DestroyNotificationHandle * mq_nh
Handle where we registered with mq to be told about the MQ&#39;s destruction.
Definition: nc.c:57
#define GNUNET_free(ptr)
Wrapper around free.