1/* Licensed to the Apache Software Foundation (ASF) under one or more
2 * contributor license agreements.  See the NOTICE file distributed with
3 * this work for additional information regarding copyright ownership.
4 * The ASF licenses this file to You under the Apache License, Version 2.0
5 * (the "License"); you may not use this file except in compliance with
6 * the License.  You may obtain a copy of the License at
7 *
8 *     http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include "apr.h"
18#include "apr_strings.h"
19#include "apr_arch_global_mutex.h"
20#include "apr_proc_mutex.h"
21#include "apr_thread_mutex.h"
22#include "apr_portable.h"
23
24static apr_status_t global_mutex_cleanup(void *data)
25{
26    apr_global_mutex_t *m = (apr_global_mutex_t *)data;
27    apr_status_t rv;
28
29    rv = apr_proc_mutex_destroy(m->proc_mutex);
30
31#if APR_HAS_THREADS
32    if (m->thread_mutex) {
33        if (rv != APR_SUCCESS) {
34            (void)apr_thread_mutex_destroy(m->thread_mutex);
35        }
36        else {
37            rv = apr_thread_mutex_destroy(m->thread_mutex);
38        }
39    }
40#endif /* APR_HAS_THREADS */
41
42    return rv;
43}
44
45APR_DECLARE(apr_status_t) apr_global_mutex_create(apr_global_mutex_t **mutex,
46                                                  const char *fname,
47                                                  apr_lockmech_e mech,
48                                                  apr_pool_t *pool)
49{
50    apr_status_t rv;
51    apr_global_mutex_t *m;
52
53    m = (apr_global_mutex_t *)apr_palloc(pool, sizeof(*m));
54    m->pool = pool;
55
56    rv = apr_proc_mutex_create(&m->proc_mutex, fname, mech, m->pool);
57    if (rv != APR_SUCCESS) {
58        return rv;
59    }
60
61#if APR_HAS_THREADS
62    if (m->proc_mutex->inter_meth->flags & APR_PROCESS_LOCK_MECH_IS_GLOBAL) {
63        m->thread_mutex = NULL; /* We don't need a thread lock. */
64    }
65    else {
66        rv = apr_thread_mutex_create(&m->thread_mutex,
67                                     APR_THREAD_MUTEX_DEFAULT, m->pool);
68        if (rv != APR_SUCCESS) {
69            rv = apr_proc_mutex_destroy(m->proc_mutex);
70            return rv;
71        }
72    }
73#endif /* APR_HAS_THREADS */
74
75    apr_pool_cleanup_register(m->pool, (void *)m,
76                              global_mutex_cleanup, apr_pool_cleanup_null);
77    *mutex = m;
78    return APR_SUCCESS;
79}
80
81APR_DECLARE(apr_status_t) apr_global_mutex_child_init(
82                              apr_global_mutex_t **mutex,
83                              const char *fname,
84                              apr_pool_t *pool)
85{
86    apr_status_t rv;
87
88    rv = apr_proc_mutex_child_init(&((*mutex)->proc_mutex), fname, pool);
89    return rv;
90}
91
92APR_DECLARE(apr_status_t) apr_global_mutex_lock(apr_global_mutex_t *mutex)
93{
94    apr_status_t rv;
95
96#if APR_HAS_THREADS
97    if (mutex->thread_mutex) {
98        rv = apr_thread_mutex_lock(mutex->thread_mutex);
99        if (rv != APR_SUCCESS) {
100            return rv;
101        }
102    }
103#endif /* APR_HAS_THREADS */
104
105    rv = apr_proc_mutex_lock(mutex->proc_mutex);
106
107#if APR_HAS_THREADS
108    if (rv != APR_SUCCESS) {
109        if (mutex->thread_mutex) {
110            (void)apr_thread_mutex_unlock(mutex->thread_mutex);
111        }
112    }
113#endif /* APR_HAS_THREADS */
114
115    return rv;
116}
117
118APR_DECLARE(apr_status_t) apr_global_mutex_trylock(apr_global_mutex_t *mutex)
119{
120    apr_status_t rv;
121
122#if APR_HAS_THREADS
123    if (mutex->thread_mutex) {
124        rv = apr_thread_mutex_trylock(mutex->thread_mutex);
125        if (rv != APR_SUCCESS) {
126            return rv;
127        }
128    }
129#endif /* APR_HAS_THREADS */
130
131    rv = apr_proc_mutex_trylock(mutex->proc_mutex);
132
133#if APR_HAS_THREADS
134    if (rv != APR_SUCCESS) {
135        if (mutex->thread_mutex) {
136            (void)apr_thread_mutex_unlock(mutex->thread_mutex);
137        }
138    }
139#endif /* APR_HAS_THREADS */
140
141    return rv;
142}
143
144APR_DECLARE(apr_status_t) apr_global_mutex_unlock(apr_global_mutex_t *mutex)
145{
146    apr_status_t rv;
147
148    rv = apr_proc_mutex_unlock(mutex->proc_mutex);
149#if APR_HAS_THREADS
150    if (mutex->thread_mutex) {
151        if (rv != APR_SUCCESS) {
152            (void)apr_thread_mutex_unlock(mutex->thread_mutex);
153        }
154        else {
155            rv = apr_thread_mutex_unlock(mutex->thread_mutex);
156        }
157    }
158#endif /* APR_HAS_THREADS */
159    return rv;
160}
161
162APR_DECLARE(apr_status_t) apr_os_global_mutex_get(apr_os_global_mutex_t *ospmutex,
163                                                apr_global_mutex_t *pmutex)
164{
165    ospmutex->pool = pmutex->pool;
166    ospmutex->proc_mutex = pmutex->proc_mutex;
167#if APR_HAS_THREADS
168    ospmutex->thread_mutex = pmutex->thread_mutex;
169#endif
170    return APR_SUCCESS;
171}
172
173APR_DECLARE(apr_status_t) apr_global_mutex_destroy(apr_global_mutex_t *mutex)
174{
175    return apr_pool_cleanup_run(mutex->pool, mutex, global_mutex_cleanup);
176}
177
178APR_DECLARE(const char *) apr_global_mutex_lockfile(apr_global_mutex_t *mutex)
179{
180    return apr_proc_mutex_lockfile(mutex->proc_mutex);
181}
182
183APR_DECLARE(const char *) apr_global_mutex_name(apr_global_mutex_t *mutex)
184{
185    return apr_proc_mutex_name(mutex->proc_mutex);
186}
187
188APR_POOL_IMPLEMENT_ACCESSOR(global_mutex)
189