xref: /haiku/src/system/libroot/posix/glibc/include/bits/libc-lock.h (revision f5e61f7174f7a30a7189fc79f92a1b0798361b27)
1 /* libc-internal interface for mutex locks.  NPTL version.
2    Copyright (C) 1996-2015 Free Software Foundation, Inc.
3    This file is part of the GNU C Library.
4 
5    The GNU C Library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public License as
7    published by the Free Software Foundation; either version 2.1 of the
8    License, or (at your option) any later version.
9 
10    The GNU C Library is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13    Lesser General Public License for more details.
14 
15    You should have received a copy of the GNU Lesser General Public
16    License along with the GNU C Library; see the file COPYING.LIB.  If
17    not, see <http://www.gnu.org/licenses/>.  */
18 
19 #ifndef _BITS_LIBC_LOCK_H
20 #define _BITS_LIBC_LOCK_H 1
21 
22 #include <pthread.h>
23 #define __need_NULL
24 #include <stddef.h>
25 
26 #define __libc_maybe_call(func, args, else) func args
27 #define __pthread_mutex_init pthread_mutex_init
28 #define __pthread_mutex_destroy pthread_mutex_destroy
29 #define __pthread_mutexattr_init pthread_mutexattr_init
30 #define __pthread_mutexattr_destroy pthread_mutexattr_destroy
31 #define __pthread_mutexattr_settype pthread_mutexattr_settype
32 #define __pthread_mutex_lock pthread_mutex_lock
33 #define __pthread_mutex_unlock pthread_mutex_unlock
34 #define PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP	PTHREAD_RECURSIVE_MUTEX_INITIALIZER
35 #define PTHREAD_MUTEX_RECURSIVE_NP	PTHREAD_MUTEX_RECURSIVE
36 
37 /* Mutex type.  */
38 typedef struct { pthread_mutex_t mutex; } __libc_lock_recursive_t;
39 
40 /* Define a lock variable NAME with storage class CLASS.  The lock must be
41    initialized with __libc_lock_init before it can be used (or define it
42    with __libc_lock_define_initialized, below).  Use `extern' for CLASS to
43    declare a lock defined in another module.  In public structure
44    definitions you must use a pointer to the lock structure (i.e., NAME
45    begins with a `*'), because its storage size will not be known outside
46    of libc.  */
47 #define __libc_lock_define_recursive(CLASS,NAME) \
48   CLASS __libc_lock_recursive_t NAME;
49 
50 /* Define an initialized recursive lock variable NAME with storage
51    class CLASS.  */
52 # define __libc_lock_define_initialized_recursive(CLASS,NAME) \
53   CLASS __libc_lock_recursive_t NAME = _LIBC_LOCK_RECURSIVE_INITIALIZER;
54 # define _LIBC_LOCK_RECURSIVE_INITIALIZER \
55   {PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP}
56 
57 /* Initialize a recursive mutex.  */
58 # define __libc_lock_init_recursive(NAME) \
59   do {									      \
60     pthread_mutexattr_t __attr;					      \
61 	__pthread_mutexattr_init (&__attr);				      \
62 	__pthread_mutexattr_settype (&__attr, PTHREAD_MUTEX_RECURSIVE_NP);    \
63 	__pthread_mutex_init (&(NAME).mutex, &__attr);			      \
64 	__pthread_mutexattr_destroy (&__attr);				      \
65   } while (0)
66 
67 /* Finalize recursive named lock.  */
68 # define __libc_lock_fini_recursive(NAME) \
69   __libc_maybe_call (__pthread_mutex_destroy, (&(NAME).mutex), 0)
70 
71 /* Lock the recursive named lock variable.  */
72 # define __libc_lock_lock_recursive(NAME) \
73   __libc_maybe_call (__pthread_mutex_lock, (&(NAME).mutex), 0)
74 
75 /* Try to lock the recursive named lock variable.  */
76 # define __libc_lock_trylock_recursive(NAME) \
77   __libc_maybe_call (__pthread_mutex_trylock, (&(NAME).mutex), 0)
78 
79 /* Unlock the recursive named lock variable.  */
80 # define __libc_lock_unlock_recursive(NAME) \
81   __libc_maybe_call (__pthread_mutex_unlock, (&(NAME).mutex), 0)
82 
83 /* Start critical region with cleanup.  */
84 #define __libc_cleanup_region_start(DOIT, FCT, ARG) \
85 
86 /* End critical region with cleanup.  */
87 #define __libc_cleanup_region_end(DOIT) \
88 
89 /* Sometimes we have to exit the block in the middle.  */
90 #define __libc_cleanup_end(DOIT) \
91 
92 /* Create thread-specific key.  */
93 #define __libc_key_create(KEY, DESTRUCTOR) \
94   1
95 
96 /* Get thread-specific data.  */
97 #define __libc_getspecific(KEY) \
98   0
99 
100 /* Set thread-specific data.  */
101 #define __libc_setspecific(KEY, VALUE) \
102   0
103 
104 
105 /* Register handlers to execute before and after `fork'.  */
106 #define __libc_atfork(PREPARE, PARENT, CHILD) \
107   0
108 
109 #endif	/* bits/libc-lock.h */
110