aboutsummaryrefslogtreecommitdiff
path: root/src/util/nc.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/util/nc.c')
-rw-r--r--src/util/nc.c227
1 files changed, 0 insertions, 227 deletions
diff --git a/src/util/nc.c b/src/util/nc.c
deleted file mode 100644
index 49c95c14e..000000000
--- a/src/util/nc.c
+++ /dev/null
@@ -1,227 +0,0 @@
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
21/**
22 * @file util/nc.c
23 * @brief convenience functions for transmission of
24 * messages to multiple clients
25 * @author Christian Grothoff
26 */
27
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
34/**
35 * Lists of subscribers we manage for notifications.
36 */
37struct SubscriberList
38{
39 /**
40 * This is a doubly linked list.
41 */
42 struct SubscriberList *next;
43
44 /**
45 * This is a doubly linked list.
46 */
47 struct SubscriberList *prev;
48
49 /**
50 * Overall context this subscriber belongs to.
51 */
52 struct GNUNET_NotificationContext *nc;
53
54 /**
55 * Handle where we registered with @e mq to be told about
56 * the MQ's destruction.
57 */
58 struct GNUNET_MQ_DestroyNotificationHandle *mq_nh;
59
60 /**
61 * Message queue for the subscriber.
62 */
63 struct GNUNET_MQ_Handle *mq;
64};
65
66
67/**
68 * The notification context is the key datastructure for a convenience
69 * API used for transmission of notifications to the subscriber until the
70 * subscriber disconnects (or the notification context is destroyed, in
71 * which case we disconnect these subscribers). Essentially, all
72 * (notification) messages are queued up until the subscriber is able to
73 * read them.
74 */
75struct GNUNET_NotificationContext
76{
77 /**
78 * Head of list of subscribers receiving notifications.
79 */
80 struct SubscriberList *subscribers_head;
81
82 /**
83 * Tail of list of subscribers receiving notifications.
84 */
85 struct SubscriberList *subscribers_tail;
86
87 /**
88 * Maximum number of optional messages to queue per subscriber.
89 */
90 unsigned int queue_length;
91};
92
93
94/**
95 * Subscriber has disconnected, clean up.
96 *
97 * @param cls our `struct SubscriberList *`
98 */
99static void
100handle_mq_destroy (void *cls)
101{
102 struct SubscriberList *pos = cls;
103 struct GNUNET_NotificationContext *nc = pos->nc;
104
105 GNUNET_CONTAINER_DLL_remove (nc->subscribers_head,
106 nc->subscribers_tail,
107 pos);
108 GNUNET_free (pos);
109}
110
111
112/**
113 * Create a new notification context.
114 *
115 * @param queue_length maximum number of messages to keep in
116 * the notification queue; optional messages are dropped
117 * if the queue gets longer than this number of messages
118 * @return handle to the notification context
119 */
120struct GNUNET_NotificationContext *
121GNUNET_notification_context_create (unsigned int queue_length)
122{
123 struct GNUNET_NotificationContext *nc;
124
125 nc = GNUNET_new (struct GNUNET_NotificationContext);
126 nc->queue_length = queue_length;
127 return nc;
128}
129
130
131/**
132 * Destroy the context, force disconnect for all subscribers.
133 *
134 * @param nc context to destroy.
135 */
136void
137GNUNET_notification_context_destroy (struct GNUNET_NotificationContext *nc)
138{
139 struct SubscriberList *pos;
140
141 while (NULL != (pos = nc->subscribers_head))
142 {
143 GNUNET_CONTAINER_DLL_remove (nc->subscribers_head,
144 nc->subscribers_tail,
145 pos);
146 GNUNET_MQ_destroy_notify_cancel (pos->mq_nh);
147 GNUNET_free (pos);
148 }
149 GNUNET_free (nc);
150}
151
152
153/**
154 * Add a subscriber to the notification context.
155 *
156 * @param nc context to modify
157 * @param mq message queue add
158 */
159void
160GNUNET_notification_context_add (struct GNUNET_NotificationContext *nc,
161 struct GNUNET_MQ_Handle *mq)
162{
163 struct SubscriberList *cl;
164
165 for (cl = nc->subscribers_head; NULL != cl; cl = cl->next)
166 if (cl->mq == mq)
167 return;
168 /* already present */
169 cl = GNUNET_new (struct SubscriberList);
170 GNUNET_CONTAINER_DLL_insert (nc->subscribers_head,
171 nc->subscribers_tail,
172 cl);
173 cl->nc = nc;
174 cl->mq = mq;
175 cl->mq_nh = GNUNET_MQ_destroy_notify (cl->mq,
176 &handle_mq_destroy,
177 cl);
178}
179
180
181/**
182 * Send a message to all subscribers of this context.
183 *
184 * @param nc context to modify
185 * @param msg message to send
186 * @param can_drop can this message be dropped due to queue length limitations
187 */
188void
189GNUNET_notification_context_broadcast (struct GNUNET_NotificationContext *nc,
190 const struct GNUNET_MessageHeader *msg,
191 int can_drop)
192{
193 struct SubscriberList *pos;
194 struct GNUNET_MQ_Envelope *env;
195
196 for (pos = nc->subscribers_head; NULL != pos; pos = pos->next)
197 {
198 if ((GNUNET_YES == can_drop) &&
199 (GNUNET_MQ_get_length (pos->mq) > nc->queue_length))
200 continue;
201 env = GNUNET_MQ_msg_copy (msg);
202 GNUNET_MQ_send (pos->mq,
203 env);
204 }
205}
206
207
208/**
209 * Return active number of subscribers in this context.
210 *
211 * @param nc context to query
212 * @return number of current subscribers
213 */
214unsigned int
215GNUNET_notification_context_get_size (struct GNUNET_NotificationContext *nc)
216{
217 unsigned int num;
218 struct SubscriberList *pos;
219
220 num = 0;
221 for (pos = nc->subscribers_head; NULL != pos; pos = pos->next)
222 num++;
223 return num;
224}
225
226
227/* end of nc.c */
generated by cgit v1.2.3 (git 2.39.1) at 2024-04-24 22:31:02 +0000