a42a5827af1ad7dd8d78a717ba4b2bd49a3b9184
[strongswan.git] / Source / charon / job_queue.c
1 /**
2 * @file job_queue.c
3 *
4 * @brief Job-Queue based on linked_list_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 <stdlib.h>
24 #include <pthread.h>
25 #include <freeswan.h>
26 #include <pluto/constants.h>
27 #include <pluto/defs.h>
28
29 #include "job_queue.h"
30 #include "linked_list.h"
31
32 /**
33 * @brief Private Variables and Functions of job_queue class
34 *
35 */
36 typedef struct private_job_queue_s private_job_queue_t;
37
38
39 struct private_job_queue_s {
40 job_queue_t public;
41
42 /**
43 * The jobs are stored in a linked list
44 */
45 linked_list_t *list;
46 /**
47 * access to linked_list is locked through this mutex
48 */
49 pthread_mutex_t mutex;
50
51 /**
52 * If the queue is empty a thread has to wait
53 * This condvar is used to wake up such a thread
54 */
55 pthread_cond_t condvar;
56 };
57
58
59 /**
60 * @brief implements function get_count of job_queue_t
61 */
62 status_t get_count(private_job_queue_t *this, int *count)
63 {
64 pthread_mutex_lock(&(this->mutex));
65 this->list->get_count(this->list,count);
66 pthread_mutex_unlock(&(this->mutex));
67 return SUCCESS;
68 }
69
70 /**
71 * @brief implements function get of job_queue_t
72 */
73 status_t get(private_job_queue_t *this, job_t **job)
74 {
75 int count;
76 int oldstate;
77 pthread_mutex_lock(&(this->mutex));
78 /* go to wait while no jobs available */
79 this->list->get_count(this->list,&count);
80 while(count == 0)
81 {
82 /* add mutex unlock handler for cancellation, enable cancellation */
83 pthread_cleanup_push((void(*)(void*))pthread_mutex_unlock, (void*)&(this->mutex));
84 pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, &oldstate);
85 pthread_cond_wait( &(this->condvar), &(this->mutex));
86
87 /* reset cancellation, remove mutex-unlock handler (without executing) */
88 pthread_setcancelstate(oldstate, NULL);
89 pthread_cleanup_pop(0);
90 this->list->get_count(this->list,&count);
91 }
92 this->list->remove_first(this->list,(void **) job);
93 pthread_mutex_unlock(&(this->mutex));
94 return SUCCESS;
95 }
96
97 /**
98 * @brief implements function add of job_queue_t
99 */
100 status_t add(private_job_queue_t *this, job_t *job)
101 {
102 pthread_mutex_lock(&(this->mutex));
103 this->list->insert_last(this->list,job);
104 pthread_cond_signal( &(this->condvar));
105 pthread_mutex_unlock(&(this->mutex));
106 return SUCCESS;
107 }
108
109 /**
110 * @brief implements function destroy of job_queue_t
111 *
112 */
113 status_t job_queue_destroy (private_job_queue_t *this)
114 {
115 int count;
116 this->list->get_count(this->list,&count);
117
118 while (count > 0)
119 {
120 job_t *job;
121 if (this->list->remove_first(this->list,(void *) &job) != SUCCESS)
122 {
123 this->list->destroy(this->list);
124 break;
125 }
126 job->destroy(job);
127 this->list->get_count(this->list,&count);
128 }
129 this->list->destroy(this->list);
130
131 pthread_mutex_destroy(&(this->mutex));
132
133 pthread_cond_destroy(&(this->condvar));
134
135 pfree(this);
136 return SUCCESS;
137 }
138
139 /*
140 *
141 * Documented in header
142 */
143 job_queue_t *job_queue_create()
144 {
145 linked_list_t *linked_list = linked_list_create();
146 if (linked_list == NULL)
147 {
148 return NULL;
149 }
150
151 private_job_queue_t *this = alloc_thing(private_job_queue_t, "private_job_queue_t");
152 if (this == NULL)
153 {
154 linked_list->destroy(linked_list);
155 return NULL;
156 }
157
158 this->public.get_count = (status_t(*)(job_queue_t*, int*))get_count;
159 this->public.get = (status_t(*)(job_queue_t*, job_t**))get;
160 this->public.add = (status_t(*)(job_queue_t*, job_t*))add;
161 this->public.destroy = (status_t(*)(job_queue_t*))job_queue_destroy;
162
163 this->list = linked_list;
164 pthread_mutex_init(&(this->mutex), NULL);
165 pthread_cond_init(&(this->condvar), NULL);
166
167 return (&this->public);
168 }