25ad1aaae123661d39b52f8de3854025ca8438bb
[strongswan.git] / Source / charon / queues / send_queue.c
1 /**
2 * @file send_queue.c
3 *
4 * @brief Implementation of send_queue_t.
5 *
6 */
7
8 /*
9 * Copyright (C) 2005 Jan Hutter, Martin Willi
10 * Hochschule fuer Technik Rapperswil
11 *
12 * This program is free software; you can redistribute it and/or modify it
13 * under the terms of the GNU General Public License as published by the
14 * Free Software Foundation; either version 2 of the License, or (at your
15 * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
16 *
17 * This program is distributed in the hope that it will be useful, but
18 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
19 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
20 * for more details.
21 */
22
23 #include <pthread.h>
24
25 #include "send_queue.h"
26
27 #include <utils/allocator.h>
28 #include <utils/linked_list.h>
29
30
31 typedef struct private_send_queue_t private_send_queue_t;
32
33 /**
34 * @brief Private Variables and Functions of send_queue class
35 *
36 */
37 struct private_send_queue_t {
38 /**
39 * Public part of the send_queue_t object
40 */
41 send_queue_t public;
42
43 /**
44 * The packets are stored in a linked list
45 */
46 linked_list_t *list;
47
48 /**
49 * access to linked_list is locked through this mutex
50 */
51 pthread_mutex_t mutex;
52
53 /**
54 * If the queue is empty a thread has to wait
55 * This condvar is used to wake up such a thread
56 */
57 pthread_cond_t condvar;
58 };
59
60
61 /**
62 * implements send_queue_t.get_count
63 */
64 static int get_count(private_send_queue_t *this)
65 {
66 int count;
67 pthread_mutex_lock(&(this->mutex));
68 count = this->list->get_count(this->list);
69 pthread_mutex_unlock(&(this->mutex));
70 return count;
71 }
72
73 /**
74 * implements send_queue_t.get
75 */
76 static packet_t *get(private_send_queue_t *this)
77 {
78 int oldstate;
79 packet_t *packet;
80 pthread_mutex_lock(&(this->mutex));
81 /* go to wait while no packets available */
82
83 while(this->list->get_count(this->list) == 0)
84 {
85 /* add mutex unlock handler for cancellation, enable cancellation */
86 pthread_cleanup_push((void(*)(void*))pthread_mutex_unlock, (void*)&(this->mutex));
87 pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, &oldstate);
88 pthread_cond_wait( &(this->condvar), &(this->mutex));
89
90 /* reset cancellation, remove mutex-unlock handler (without executing) */
91 pthread_setcancelstate(oldstate, NULL);
92 pthread_cleanup_pop(0);
93 }
94 this->list->remove_first(this->list,(void **)&packet);
95 pthread_mutex_unlock(&(this->mutex));
96 return packet;
97 }
98
99 /**
100 * implements send_queue_t.add
101 */
102 static void add(private_send_queue_t *this, packet_t *packet)
103 {
104 pthread_mutex_lock(&(this->mutex));
105 this->list->insert_last(this->list,packet);
106 pthread_cond_signal( &(this->condvar));
107 pthread_mutex_unlock(&(this->mutex));
108 }
109
110 /**
111 * implements send_queue_t.destroy
112 */
113 static void destroy (private_send_queue_t *this)
114 {
115
116 /* destroy all packets in list before destroying list */
117 while (this->list->get_count(this->list) > 0)
118 {
119 packet_t *packet;
120 if (this->list->remove_first(this->list,(void *) &packet) != SUCCESS)
121 {
122 this->list->destroy(this->list);
123 break;
124 }
125 packet->destroy(packet);
126 }
127 this->list->destroy(this->list);
128
129 pthread_mutex_destroy(&(this->mutex));
130
131 pthread_cond_destroy(&(this->condvar));
132
133 allocator_free(this);
134 }
135
136 /*
137 *
138 * Documented in header
139 */
140 send_queue_t *send_queue_create()
141 {
142 private_send_queue_t *this = allocator_alloc_thing(private_send_queue_t);
143
144 this->public.get_count = (int(*)(send_queue_t*)) get_count;
145 this->public.get = (packet_t*(*)(send_queue_t*)) get;
146 this->public.add = (void(*)(send_queue_t*, packet_t*)) add;
147 this->public.destroy = (void(*)(send_queue_t*)) destroy;
148
149 this->list = linked_list_create();
150 pthread_mutex_init(&(this->mutex), NULL);
151 pthread_cond_init(&(this->condvar), NULL);
152
153 return (&this->public);
154 }