1
/* libc-internal interface for mutex locks. LinuxThreads version.
2
Copyright (C) 1996,1997,1998,1999,2000,2001,2002,2003,2006
3
Free Software Foundation, Inc.
4
This file is part of the GNU C Library.
6
The GNU C Library is free software; you can redistribute it and/or
7
modify it under the terms of the GNU Lesser General Public License as
8
published by the Free Software Foundation; either version 2.1 of the
9
License, or (at your option) any later version.
11
The GNU C Library is distributed in the hope that it will be useful,
12
but WITHOUT ANY WARRANTY; without even the implied warranty of
13
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14
Lesser General Public License for more details.
16
You should have received a copy of the GNU Lesser General Public
17
License along with the GNU C Library; see the file COPYING.LIB. If not,
18
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19
Boston, MA 02111-1307, USA. */
21
#ifndef _BITS_LIBC_LOCK_H
22
#define _BITS_LIBC_LOCK_H 1
26
#if defined _LIBC && !defined NOT_IN_libc
27
#include <linuxthreads/internals.h>
31
#if defined(_LIBC) || defined(_IO_MTSAFE_IO)
32
typedef pthread_mutex_t __libc_lock_t;
33
typedef struct { pthread_mutex_t mutex; } __libc_lock_recursive_t;
35
typedef pthread_rwlock_t __libc_rwlock_t;
37
typedef struct __libc_rwlock_opaque__ __libc_rwlock_t;
39
typedef __libc_lock_recursive_t __rtld_lock_recursive_t;
41
typedef struct __libc_lock_opaque__ __libc_lock_t;
42
typedef struct __libc_lock_recursive_opaque__ __libc_lock_recursive_t;
43
typedef struct __libc_rwlock_opaque__ __libc_rwlock_t;
46
/* Type for key to thread-specific data. */
47
typedef pthread_key_t __libc_key_t;
49
/* Define a lock variable NAME with storage class CLASS. The lock must be
50
initialized with __libc_lock_init before it can be used (or define it
51
with __libc_lock_define_initialized, below). Use `extern' for CLASS to
52
declare a lock defined in another module. In public structure
53
definitions you must use a pointer to the lock structure (i.e., NAME
54
begins with a `*'), because its storage size will not be known outside
56
#define __libc_lock_define(CLASS,NAME) \
57
CLASS __libc_lock_t NAME;
58
#define __libc_rwlock_define(CLASS,NAME) \
59
CLASS __libc_rwlock_t NAME;
60
#define __libc_lock_define_recursive(CLASS,NAME) \
61
CLASS __libc_lock_recursive_t NAME;
62
#define __rtld_lock_define_recursive(CLASS,NAME) \
63
CLASS __rtld_lock_recursive_t NAME;
65
/* Define an initialized lock variable NAME with storage class CLASS.
67
For the C library we take a deeper look at the initializer. For
68
this implementation all fields are initialized to zero. Therefore
69
we don't initialize the variable which allows putting it into the
70
BSS section. (Except on PA-RISC and other odd architectures, where
71
initialized locks must be set to one due to the lack of normal
72
atomic operations.) */
74
#if __LT_SPINLOCK_INIT == 0
75
# define __libc_lock_define_initialized(CLASS,NAME) \
76
CLASS __libc_lock_t NAME;
78
# define __libc_lock_define_initialized(CLASS,NAME) \
79
CLASS __libc_lock_t NAME = PTHREAD_MUTEX_INITIALIZER;
82
#define __libc_rwlock_define_initialized(CLASS,NAME) \
83
CLASS __libc_rwlock_t NAME = PTHREAD_RWLOCK_INITIALIZER;
85
/* Define an initialized recursive lock variable NAME with storage
87
#define __libc_lock_define_initialized_recursive(CLASS,NAME) \
88
CLASS __libc_lock_recursive_t NAME = _LIBC_LOCK_RECURSIVE_INITIALIZER;
89
#define _LIBC_LOCK_RECURSIVE_INITIALIZER \
90
{PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP}
92
#define __rtld_lock_define_initialized_recursive(CLASS,NAME) \
93
CLASS __rtld_lock_recursive_t NAME = _RTLD_LOCK_RECURSIVE_INITIALIZER;
94
#define _RTLD_LOCK_RECURSIVE_INITIALIZER \
95
{PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP}
97
#if defined _LIBC && defined IS_IN_libpthread
98
# define __libc_maybe_call(FUNC, ARGS, ELSE) FUNC ARGS
100
# if defined __PIC__ || (defined _LIBC && defined SHARED)
101
# define __libc_maybe_call(FUNC, ARGS, ELSE) \
102
(__extension__ ({ __typeof (FUNC) *_fn = (FUNC); \
103
_fn != NULL ? (*_fn) ARGS : ELSE; }))
105
# define __libc_maybe_call(FUNC, ARGS, ELSE) \
106
(FUNC != NULL ? FUNC ARGS : ELSE)
109
#if defined _LIBC && !defined NOT_IN_libc && defined SHARED
110
# define __libc_maybe_call2(FUNC, ARGS, ELSE) \
111
({__builtin_expect (__libc_pthread_functions.ptr_##FUNC != NULL, 0) \
112
? __libc_pthread_functions.ptr_##FUNC ARGS : ELSE; })
114
# define __libc_maybe_call2(FUNC, ARGS, ELSE) __libc_maybe_call (__##FUNC, ARGS, ELSE)
117
/* Initialize the named lock variable, leaving it in a consistent, unlocked
119
#if defined _LIBC && !defined NOT_IN_libc && defined SHARED
120
#define __libc_lock_init(NAME) \
122
(NAME).__m_count = 0; \
123
(NAME).__m_owner = NULL; \
124
(NAME).__m_kind = PTHREAD_MUTEX_TIMED_NP; \
125
(NAME).__m_lock.__status = 0; \
126
(NAME).__m_lock.__spinlock = __LT_SPINLOCK_INIT; \
129
#define __libc_lock_init(NAME) \
130
(__libc_maybe_call2 (pthread_mutex_init, (&(NAME), NULL), 0))
132
#define __libc_rwlock_init(NAME) \
133
(__libc_maybe_call (__pthread_rwlock_init, (&(NAME), NULL), 0));
135
/* Same as last but this time we initialize a recursive mutex. */
136
#if defined _LIBC && !defined NOT_IN_libc && defined SHARED
137
#define __libc_lock_init_recursive(NAME) \
139
(NAME).mutex.__m_count = 0; \
140
(NAME).mutex.__m_owner = NULL; \
141
(NAME).mutex.__m_kind = PTHREAD_MUTEX_RECURSIVE_NP; \
142
(NAME).mutex.__m_lock.__status = 0; \
143
(NAME).mutex.__m_lock.__spinlock = __LT_SPINLOCK_INIT; \
146
#define __libc_lock_init_recursive(NAME) \
148
if (__pthread_mutex_init != NULL) \
150
pthread_mutexattr_t __attr; \
151
__pthread_mutexattr_init (&__attr); \
152
__pthread_mutexattr_settype (&__attr, PTHREAD_MUTEX_RECURSIVE_NP); \
153
__pthread_mutex_init (&(NAME).mutex, &__attr); \
154
__pthread_mutexattr_destroy (&__attr); \
158
#define __rtld_lock_init_recursive(NAME) \
159
__libc_lock_init_recursive (NAME)
161
/* Finalize the named lock variable, which must be locked. It cannot be
162
used again until __libc_lock_init is called again on it. This must be
163
called on a lock variable before the containing storage is reused. */
164
#define __libc_lock_fini(NAME) \
165
(__libc_maybe_call2 (pthread_mutex_destroy, (&(NAME)), 0));
166
#define __libc_rwlock_fini(NAME) \
167
(__libc_maybe_call (__pthread_rwlock_destroy, (&(NAME)), 0));
169
/* Finalize recursive named lock. */
170
#define __libc_lock_fini_recursive(NAME) __libc_lock_fini ((NAME).mutex)
171
#define __rtld_lock_fini_recursive(NAME) __libc_lock_fini_recursive (NAME)
173
/* Lock the named lock variable. */
174
#define __libc_lock_lock(NAME) \
175
(__libc_maybe_call2 (pthread_mutex_lock, (&(NAME)), 0));
176
#define __libc_rwlock_rdlock(NAME) \
177
(__libc_maybe_call (__pthread_rwlock_rdlock, (&(NAME)), 0));
178
#define __libc_rwlock_wrlock(NAME) \
179
(__libc_maybe_call (__pthread_rwlock_wrlock, (&(NAME)), 0));
181
/* Lock the recursive named lock variable. */
182
#define __libc_lock_lock_recursive(NAME) __libc_lock_lock ((NAME).mutex)
184
/* Try to lock the named lock variable. */
185
#define __libc_lock_trylock(NAME) \
186
(__libc_maybe_call2 (pthread_mutex_trylock, (&(NAME)), 0))
187
#define __libc_rwlock_tryrdlock(NAME) \
188
(__libc_maybe_call (__pthread_rwlock_tryrdlock, (&(NAME)), 0))
189
#define __libc_rwlock_trywrlock(NAME) \
190
(__libc_maybe_call (__pthread_rwlock_trywrlock, (&(NAME)), 0))
192
/* Try to lock the recursive named lock variable. */
193
#define __libc_lock_trylock_recursive(NAME) __libc_lock_trylock ((NAME).mutex)
194
#define __rtld_lock_trylock_recursive(NAME) \
195
__libc_lock_trylock_recursive (NAME)
197
/* Unlock the named lock variable. */
198
#define __libc_lock_unlock(NAME) \
199
(__libc_maybe_call2 (pthread_mutex_unlock, (&(NAME)), 0));
200
#define __libc_rwlock_unlock(NAME) \
201
(__libc_maybe_call (__pthread_rwlock_unlock, (&(NAME)), 0));
203
/* Unlock the recursive named lock variable. */
204
#define __libc_lock_unlock_recursive(NAME) __libc_lock_unlock ((NAME).mutex)
206
#if defined _LIBC && defined SHARED
207
# define __rtld_lock_default_lock_recursive(lock) \
208
++((pthread_mutex_t *)(lock))->__m_count;
210
# define __rtld_lock_default_unlock_recursive(lock) \
211
--((pthread_mutex_t *)(lock))->__m_count;
213
# define __rtld_lock_lock_recursive(NAME) \
214
GL(dl_rtld_lock_recursive) (&(NAME).mutex)
216
# define __rtld_lock_unlock_recursive(NAME) \
217
GL(dl_rtld_unlock_recursive) (&(NAME).mutex)
219
#define __rtld_lock_lock_recursive(NAME) __libc_lock_lock_recursive (NAME)
220
#define __rtld_lock_unlock_recursive(NAME) __libc_lock_unlock_recursive (NAME)
223
/* Define once control variable. */
224
#if PTHREAD_ONCE_INIT == 0
225
/* Special case for static variables where we can avoid the initialization
227
# define __libc_once_define(CLASS, NAME) \
228
CLASS pthread_once_t NAME
230
# define __libc_once_define(CLASS, NAME) \
231
CLASS pthread_once_t NAME = PTHREAD_ONCE_INIT
234
/* Call handler iff the first call. */
235
#define __libc_once(ONCE_CONTROL, INIT_FUNCTION) \
237
if (__pthread_once != NULL) \
238
__pthread_once (&(ONCE_CONTROL), (INIT_FUNCTION)); \
239
else if ((ONCE_CONTROL) == PTHREAD_ONCE_INIT) { \
241
(ONCE_CONTROL) = 2; \
246
/* Start critical region with cleanup. */
247
#define __libc_cleanup_region_start(DOIT, FCT, ARG) \
248
{ struct _pthread_cleanup_buffer _buffer; \
249
int _avail = (DOIT) && _pthread_cleanup_push_defer != NULL; \
251
_pthread_cleanup_push_defer (&_buffer, (FCT), (ARG)); \
254
/* End critical region with cleanup. */
255
#define __libc_cleanup_region_end(DOIT) \
257
_pthread_cleanup_pop_restore (&_buffer, (DOIT)); \
261
/* Sometimes we have to exit the block in the middle. */
262
#define __libc_cleanup_end(DOIT) \
264
_pthread_cleanup_pop_restore (&_buffer, (DOIT)); \
267
#define __libc_cleanup_push(fct, arg) \
268
{ struct _pthread_cleanup_buffer _buffer; \
269
__libc_maybe_call (_pthread_cleanup_push, (&_buffer, (fct), (arg)), 0)
271
#define __libc_cleanup_pop(execute) \
272
__libc_maybe_call (_pthread_cleanup_pop, (&_buffer, execute), 0); \
275
/* Create thread-specific key. */
276
#define __libc_key_create(KEY, DESTRUCTOR) \
277
(__libc_maybe_call (__pthread_key_create, (KEY, DESTRUCTOR), 1))
279
/* Get thread-specific data. */
280
#define __libc_getspecific(KEY) \
281
(__libc_maybe_call (__pthread_getspecific, (KEY), NULL))
283
/* Set thread-specific data. */
284
#define __libc_setspecific(KEY, VALUE) \
285
(__libc_maybe_call (__pthread_setspecific, (KEY, VALUE), 0))
288
/* Register handlers to execute before and after `fork'. */
289
#define __libc_atfork(PREPARE, PARENT, CHILD) \
290
(__libc_maybe_call (__pthread_atfork, (PREPARE, PARENT, CHILD), 0))
292
/* Functions that are used by this file and are internal to the GNU C
295
extern int __pthread_mutex_init (pthread_mutex_t *__mutex,
296
__const pthread_mutexattr_t *__mutex_attr);
298
extern int __pthread_mutex_destroy (pthread_mutex_t *__mutex);
300
extern int __pthread_mutex_trylock (pthread_mutex_t *__mutex);
302
extern int __pthread_mutex_lock (pthread_mutex_t *__mutex);
304
extern int __pthread_mutex_unlock (pthread_mutex_t *__mutex);
306
extern int __pthread_mutexattr_init (pthread_mutexattr_t *__attr);
308
extern int __pthread_mutexattr_destroy (pthread_mutexattr_t *__attr);
310
extern int __pthread_mutexattr_settype (pthread_mutexattr_t *__attr,
314
extern int __pthread_rwlock_init (pthread_rwlock_t *__rwlock,
315
__const pthread_rwlockattr_t *__attr);
317
extern int __pthread_rwlock_destroy (pthread_rwlock_t *__rwlock);
319
extern int __pthread_rwlock_rdlock (pthread_rwlock_t *__rwlock);
321
extern int __pthread_rwlock_tryrdlock (pthread_rwlock_t *__rwlock);
323
extern int __pthread_rwlock_wrlock (pthread_rwlock_t *__rwlock);
325
extern int __pthread_rwlock_trywrlock (pthread_rwlock_t *__rwlock);
327
extern int __pthread_rwlock_unlock (pthread_rwlock_t *__rwlock);
330
extern int __pthread_key_create (pthread_key_t *__key,
331
void (*__destr_function) (void *));
333
extern int __pthread_setspecific (pthread_key_t __key,
334
__const void *__pointer);
336
extern void *__pthread_getspecific (pthread_key_t __key);
338
extern int __pthread_once (pthread_once_t *__once_control,
339
void (*__init_routine) (void));
341
extern int __pthread_atfork (void (*__prepare) (void),
342
void (*__parent) (void),
343
void (*__child) (void));
347
/* Make the pthread functions weak so that we can elide them from
348
single-threaded processes. */
349
#ifndef __NO_WEAK_PTHREAD_ALIASES
354
# define BP_SYM(sym) sym
356
weak_extern (BP_SYM (__pthread_mutex_init))
357
weak_extern (BP_SYM (__pthread_mutex_destroy))
358
weak_extern (BP_SYM (__pthread_mutex_lock))
359
weak_extern (BP_SYM (__pthread_mutex_trylock))
360
weak_extern (BP_SYM (__pthread_mutex_unlock))
361
weak_extern (BP_SYM (__pthread_mutexattr_init))
362
weak_extern (BP_SYM (__pthread_mutexattr_destroy))
363
weak_extern (BP_SYM (__pthread_mutexattr_settype))
364
weak_extern (BP_SYM (__pthread_rwlock_init))
365
weak_extern (BP_SYM (__pthread_rwlock_destroy))
366
weak_extern (BP_SYM (__pthread_rwlock_rdlock))
367
weak_extern (BP_SYM (__pthread_rwlock_tryrdlock))
368
weak_extern (BP_SYM (__pthread_rwlock_wrlock))
369
weak_extern (BP_SYM (__pthread_rwlock_trywrlock))
370
weak_extern (BP_SYM (__pthread_rwlock_unlock))
371
weak_extern (BP_SYM (__pthread_key_create))
372
weak_extern (BP_SYM (__pthread_setspecific))
373
weak_extern (BP_SYM (__pthread_getspecific))
374
weak_extern (BP_SYM (__pthread_once))
375
weak_extern (__pthread_initialize)
376
weak_extern (__pthread_atfork)
377
weak_extern (BP_SYM (_pthread_cleanup_push))
378
weak_extern (BP_SYM (_pthread_cleanup_pop))
379
weak_extern (BP_SYM (_pthread_cleanup_push_defer))
380
weak_extern (BP_SYM (_pthread_cleanup_pop_restore))
382
# pragma weak __pthread_mutex_init
383
# pragma weak __pthread_mutex_destroy
384
# pragma weak __pthread_mutex_lock
385
# pragma weak __pthread_mutex_trylock
386
# pragma weak __pthread_mutex_unlock
387
# pragma weak __pthread_mutexattr_init
388
# pragma weak __pthread_mutexattr_destroy
389
# pragma weak __pthread_mutexattr_settype
390
# pragma weak __pthread_rwlock_destroy
391
# pragma weak __pthread_rwlock_rdlock
392
# pragma weak __pthread_rwlock_tryrdlock
393
# pragma weak __pthread_rwlock_wrlock
394
# pragma weak __pthread_rwlock_trywrlock
395
# pragma weak __pthread_rwlock_unlock
396
# pragma weak __pthread_key_create
397
# pragma weak __pthread_setspecific
398
# pragma weak __pthread_getspecific
399
# pragma weak __pthread_once
400
# pragma weak __pthread_initialize
401
# pragma weak __pthread_atfork
402
# pragma weak _pthread_cleanup_push_defer
403
# pragma weak _pthread_cleanup_pop_restore
404
# pragma weak _pthread_cleanup_push
405
# pragma weak _pthread_cleanup_pop
409
/* We need portable names for some functions. E.g., when they are
410
used as argument to __libc_cleanup_region_start. */
411
#define __libc_mutex_unlock __pthread_mutex_unlock
413
#endif /* bits/libc-lock.h */