global_mutex.c revision 362181 
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
19#include "apr_strings.h"
20#include "apr_arch_global_mutex.h"
21#include "apr_proc_mutex.h"
22#include "apr_thread_mutex.h"
23#include "apr_portable.h"
24
25static apr_status_t global_mutex_cleanup(void *data)
26{
27    apr_global_mutex_t *m = (apr_global_mutex_t *)data;
28    apr_status_t rv;
29
30    rv = apr_proc_mutex_destroy(m->proc_mutex);
31
32#if APR_HAS_THREADS
33    if (m->thread_mutex) {
34        if (rv != APR_SUCCESS) {
35            (void)apr_thread_mutex_destroy(m->thread_mutex);
36        }
37        else {
38            rv = apr_thread_mutex_destroy(m->thread_mutex);
39        }
40    }
41#endif /* APR_HAS_THREADS */
42
43    return rv;
44}
45
46APR_DECLARE(apr_status_t) apr_global_mutex_create(apr_global_mutex_t **mutex,
47                                                  const char *fname,
48                                                  apr_lockmech_e mech,
49                                                  apr_pool_t *pool)
50{
51    apr_status_t rv;
52    apr_global_mutex_t *m;
53
54    m = (apr_global_mutex_t *)apr_palloc(pool, sizeof(*m));
55    m->pool = pool;
56
57    rv = apr_proc_mutex_create(&m->proc_mutex, fname, mech, m->pool);
58    if (rv != APR_SUCCESS) {
59        return rv;
60    }
61
62#if APR_HAS_THREADS
63    if (m->proc_mutex->meth->flags & APR_PROCESS_LOCK_MECH_IS_GLOBAL) {
64        m->thread_mutex = NULL; /* We don't need a thread lock. */
65    }
66    else {
67        rv = apr_thread_mutex_create(&m->thread_mutex,
68                                     APR_THREAD_MUTEX_DEFAULT, m->pool);
69        if (rv != APR_SUCCESS) {
70            rv = apr_proc_mutex_destroy(m->proc_mutex);
71            return rv;
72        }
73    }
74#endif /* APR_HAS_THREADS */
75
76    apr_pool_cleanup_register(m->pool, (void *)m,
77                              global_mutex_cleanup, apr_pool_cleanup_null);
78    *mutex = m;
79    return APR_SUCCESS;
80}
81
82APR_DECLARE(apr_status_t) apr_global_mutex_child_init(
83                              apr_global_mutex_t **mutex,
84                              const char *fname,
85                              apr_pool_t *pool)
86{
87    apr_status_t rv;
88
89    rv = apr_proc_mutex_child_init(&((*mutex)->proc_mutex), fname, pool);
90    return rv;
91}
92
93APR_DECLARE(apr_status_t) apr_global_mutex_lock(apr_global_mutex_t *mutex)
94{
95    apr_status_t rv;
96
97#if APR_HAS_THREADS
98    if (mutex->thread_mutex) {
99        rv = apr_thread_mutex_lock(mutex->thread_mutex);
100        if (rv != APR_SUCCESS) {
101            return rv;
102        }
103    }
104#endif /* APR_HAS_THREADS */
105
106    rv = apr_proc_mutex_lock(mutex->proc_mutex);
107
108#if APR_HAS_THREADS
109    if (rv != APR_SUCCESS) {
110        if (mutex->thread_mutex) {
111            (void)apr_thread_mutex_unlock(mutex->thread_mutex);
112        }
113    }
114#endif /* APR_HAS_THREADS */
115
116    return rv;
117}
118
119APR_DECLARE(apr_status_t) apr_global_mutex_trylock(apr_global_mutex_t *mutex)
120{
121    apr_status_t rv;
122
123#if APR_HAS_THREADS
124    if (mutex->thread_mutex) {
125        rv = apr_thread_mutex_trylock(mutex->thread_mutex);
126        if (rv != APR_SUCCESS) {
127            return rv;
128        }
129    }
130#endif /* APR_HAS_THREADS */
131
132    rv = apr_proc_mutex_trylock(mutex->proc_mutex);
133
134#if APR_HAS_THREADS
135    if (rv != APR_SUCCESS) {
136        if (mutex->thread_mutex) {
137            (void)apr_thread_mutex_unlock(mutex->thread_mutex);
138        }
139    }
140#endif /* APR_HAS_THREADS */
141
142    return rv;
143}
144
145APR_DECLARE(apr_status_t) apr_global_mutex_timedlock(apr_global_mutex_t *mutex,
146                                                 apr_interval_time_t timeout)
147{
148#if APR_HAS_TIMEDLOCKS
149    apr_status_t rv;
150
151#if APR_HAS_THREADS
152    if (mutex->thread_mutex) {
153        apr_time_t expiry = 0;
154        if (timeout > 0) {
155            expiry = apr_time_now() + timeout;
156        }
157        rv = apr_thread_mutex_timedlock(mutex->thread_mutex, timeout);
158        if (rv != APR_SUCCESS) {
159            return rv;
160        }
161        if (expiry) {
162            timeout = expiry - apr_time_now();
163            if (timeout < 0) {
164                timeout = 0;
165            }
166        }
167    }
168#endif /* APR_HAS_THREADS */
169
170    rv = apr_proc_mutex_timedlock(mutex->proc_mutex, timeout);
171
172#if APR_HAS_THREADS
173    if (rv != APR_SUCCESS) {
174        if (mutex->thread_mutex) {
175            (void)apr_thread_mutex_unlock(mutex->thread_mutex);
176        }
177    }
178#endif /* APR_HAS_THREADS */
179
180    return rv;
181#else  /* APR_HAS_TIMEDLOCKS */
182    return APR_ENOTIMPL;
183#endif
184}
185
186APR_DECLARE(apr_status_t) apr_global_mutex_unlock(apr_global_mutex_t *mutex)
187{
188    apr_status_t rv;
189
190    rv = apr_proc_mutex_unlock(mutex->proc_mutex);
191#if APR_HAS_THREADS
192    if (mutex->thread_mutex) {
193        if (rv != APR_SUCCESS) {
194            (void)apr_thread_mutex_unlock(mutex->thread_mutex);
195        }
196        else {
197            rv = apr_thread_mutex_unlock(mutex->thread_mutex);
198        }
199    }
200#endif /* APR_HAS_THREADS */
201    return rv;
202}
203
204APR_DECLARE(apr_status_t) apr_os_global_mutex_get(apr_os_global_mutex_t *ospmutex,
205                                                apr_global_mutex_t *pmutex)
206{
207    ospmutex->pool = pmutex->pool;
208    ospmutex->proc_mutex = pmutex->proc_mutex;
209#if APR_HAS_THREADS
210    ospmutex->thread_mutex = pmutex->thread_mutex;
211#endif
212    return APR_SUCCESS;
213}
214
215APR_DECLARE(apr_status_t) apr_global_mutex_destroy(apr_global_mutex_t *mutex)
216{
217    return apr_pool_cleanup_run(mutex->pool, mutex, global_mutex_cleanup);
218}
219
220APR_DECLARE(const char *) apr_global_mutex_lockfile(apr_global_mutex_t *mutex)
221{
222    return apr_proc_mutex_lockfile(mutex->proc_mutex);
223}
224
225APR_DECLARE(apr_lockmech_e) apr_global_mutex_mech(apr_global_mutex_t *mutex)
226{
227    return apr_proc_mutex_mech(mutex->proc_mutex);
228}
229
230APR_DECLARE(const char *) apr_global_mutex_name(apr_global_mutex_t *mutex)
231{
232    return apr_proc_mutex_name(mutex->proc_mutex);
233}
234
235APR_PERMS_SET_IMPLEMENT(global_mutex)
236{
237    apr_status_t rv;
238    apr_global_mutex_t *mutex = (apr_global_mutex_t *)theglobal_mutex;
239
240    rv = APR_PERMS_SET_FN(proc_mutex)(mutex->proc_mutex, perms, uid, gid);
241    return rv;
242}
243
244APR_POOL_IMPLEMENT_ACCESSOR(global_mutex)
245
246