Apache Portable Runtime
Main Page
Related Pages
Modules
Data Structures
Files
File List
Globals
All
Data Structures
Files
Functions
Variables
Typedefs
Enumerations
Enumerator
Macros
Groups
Pages
include
apr_proc_mutex.h
Go to the documentation of this file.
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
#ifndef APR_PROC_MUTEX_H
18
#define APR_PROC_MUTEX_H
19
20
/**
21
* @file apr_proc_mutex.h
22
* @brief APR Process Locking Routines
23
*/
24
25
#include "
apr.h
"
26
#include "
apr_pools.h
"
27
#include "
apr_errno.h
"
28
29
#ifdef __cplusplus
30
extern
"C"
{
31
#endif
/* __cplusplus */
32
33
/**
34
* @defgroup apr_proc_mutex Process Locking Routines
35
* @ingroup APR
36
* @{
37
*/
38
39
/**
40
* Enumerated potential types for APR process locking methods
41
* @warning Check APR_HAS_foo_SERIALIZE defines to see if the platform supports
42
* APR_LOCK_foo. Only APR_LOCK_DEFAULT is portable.
43
*/
44
typedef
enum
{
45
APR_LOCK_FCNTL
,
/**< fcntl() */
46
APR_LOCK_FLOCK
,
/**< flock() */
47
APR_LOCK_SYSVSEM
,
/**< System V Semaphores */
48
APR_LOCK_PROC_PTHREAD
,
/**< POSIX pthread process-based locking */
49
APR_LOCK_POSIXSEM
,
/**< POSIX semaphore process-based locking */
50
APR_LOCK_DEFAULT
/**< Use the default process lock */
51
}
apr_lockmech_e
;
52
53
/** Opaque structure representing a process mutex. */
54
typedef
struct
apr_proc_mutex_t
apr_proc_mutex_t
;
55
56
/* Function definitions */
57
58
/**
59
* Create and initialize a mutex that can be used to synchronize processes.
60
* @param mutex the memory address where the newly created mutex will be
61
* stored.
62
* @param fname A file name to use if the lock mechanism requires one. This
63
* argument should always be provided. The lock code itself will
64
* determine if it should be used.
65
* @param mech The mechanism to use for the interprocess lock, if any; one of
66
* <PRE>
67
* APR_LOCK_FCNTL
68
* APR_LOCK_FLOCK
69
* APR_LOCK_SYSVSEM
70
* APR_LOCK_POSIXSEM
71
* APR_LOCK_PROC_PTHREAD
72
* APR_LOCK_DEFAULT pick the default mechanism for the platform
73
* </PRE>
74
* @param pool the pool from which to allocate the mutex.
75
* @see apr_lockmech_e
76
* @warning Check APR_HAS_foo_SERIALIZE defines to see if the platform supports
77
* APR_LOCK_foo. Only APR_LOCK_DEFAULT is portable.
78
*/
79
APR_DECLARE
(
apr_status_t
)
apr_proc_mutex_create
(
apr_proc_mutex_t
**mutex,
80
const
char
*fname,
81
apr_lockmech_e
mech,
82
apr_pool_t
*pool);
83
84
/**
85
* Re-open a mutex in a child process.
86
* @param mutex The newly re-opened mutex structure.
87
* @param fname A file name to use if the mutex mechanism requires one. This
88
* argument should always be provided. The mutex code itself will
89
* determine if it should be used. This filename should be the
90
* same one that was passed to apr_proc_mutex_create().
91
* @param pool The pool to operate on.
92
* @remark This function must be called to maintain portability, even
93
* if the underlying lock mechanism does not require it.
94
*/
95
APR_DECLARE
(
apr_status_t
)
apr_proc_mutex_child_init
(
apr_proc_mutex_t
**mutex,
96
const
char
*fname,
97
apr_pool_t
*pool);
98
99
/**
100
* Acquire the lock for the given mutex. If the mutex is already locked,
101
* the current thread will be put to sleep until the lock becomes available.
102
* @param mutex the mutex on which to acquire the lock.
103
*/
104
APR_DECLARE
(
apr_status_t
)
apr_proc_mutex_lock
(
apr_proc_mutex_t
*mutex);
105
106
/**
107
* Attempt to acquire the lock for the given mutex. If the mutex has already
108
* been acquired, the call returns immediately with APR_EBUSY. Note: it
109
* is important that the APR_STATUS_IS_EBUSY(s) macro be used to determine
110
* if the return value was APR_EBUSY, for portability reasons.
111
* @param mutex the mutex on which to attempt the lock acquiring.
112
*/
113
APR_DECLARE
(
apr_status_t
)
apr_proc_mutex_trylock
(
apr_proc_mutex_t
*mutex);
114
115
/**
116
* Release the lock for the given mutex.
117
* @param mutex the mutex from which to release the lock.
118
*/
119
APR_DECLARE
(
apr_status_t
)
apr_proc_mutex_unlock
(
apr_proc_mutex_t
*mutex);
120
121
/**
122
* Destroy the mutex and free the memory associated with the lock.
123
* @param mutex the mutex to destroy.
124
*/
125
APR_DECLARE
(
apr_status_t
)
apr_proc_mutex_destroy
(
apr_proc_mutex_t
*mutex);
126
127
/**
128
* Destroy the mutex and free the memory associated with the lock.
129
* @param mutex the mutex to destroy.
130
* @note This function is generally used to kill a cleanup on an already
131
* created mutex
132
*/
133
APR_DECLARE
(
apr_status_t
)
apr_proc_mutex_cleanup
(
void
*mutex);
134
135
/**
136
* Return the name of the lockfile for the mutex, or NULL
137
* if the mutex doesn't use a lock file
138
*/
139
140
APR_DECLARE
(const
char
*)
apr_proc_mutex_lockfile
(
apr_proc_mutex_t
*mutex);
141
142
/**
143
* Display the name of the mutex, as it relates to the actual method used.
144
* This matches the valid options for Apache's AcceptMutex directive
145
* @param mutex the name of the mutex
146
*/
147
APR_DECLARE
(const
char
*)
apr_proc_mutex_name
(
apr_proc_mutex_t
*mutex);
148
149
/**
150
* Display the name of the default mutex: APR_LOCK_DEFAULT
151
*/
152
APR_DECLARE
(const
char
*)
apr_proc_mutex_defname
(
void
);
153
154
/**
155
* Get the pool used by this proc_mutex.
156
* @return apr_pool_t the pool
157
*/
158
APR_POOL_DECLARE_ACCESSOR
(proc_mutex);
159
160
/** @} */
161
162
#ifdef __cplusplus
163
}
164
#endif
165
166
#endif
/* ! APR_PROC_MUTEX_H */
Generated on Sun Jul 7 2013 03:35:10 for Apache Portable Runtime by
1.8.1.2