summary refs log tree commit diff
path: root/linuxthreads/sysdeps/pthread/bits/libc-lock.h
blob: 2697a18371a27996e5d3cdf3e60794405a04ab90 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
/* libc-internal interface for mutex locks.  LinuxThreads version.
   Copyright (C) 1996,1997,1998,1999,2000,2001,2002,2003
   	Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public License as
   published by the Free Software Foundation; either version 2.1 of the
   License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If not,
   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#ifndef _BITS_LIBC_LOCK_H
#define _BITS_LIBC_LOCK_H 1

#include <pthread.h>

#if defined _LIBC && !defined NOT_IN_libc
#include <linuxthreads/internals.h>
#endif

/* Mutex type.  */
#if defined(_LIBC) || defined(_IO_MTSAFE_IO)
typedef pthread_mutex_t __libc_lock_t;
typedef struct { pthread_mutex_t mutex; } __libc_lock_recursive_t;
# ifdef __USE_UNIX98
typedef pthread_rwlock_t __libc_rwlock_t;
# else
typedef struct __libc_rwlock_opaque__ __libc_rwlock_t;
# endif
typedef __libc_lock_recursive_t __rtld_lock_recursive_t;
#else
typedef struct __libc_lock_opaque__ __libc_lock_t;
typedef struct __libc_lock_recursive_opaque__ __libc_lock_recursive_t;
typedef struct __libc_rwlock_opaque__ __libc_rwlock_t;
#endif

/* Type for key to thread-specific data.  */
typedef pthread_key_t __libc_key_t;

/* Define a lock variable NAME with storage class CLASS.  The lock must be
   initialized with __libc_lock_init before it can be used (or define it
   with __libc_lock_define_initialized, below).  Use `extern' for CLASS to
   declare a lock defined in another module.  In public structure
   definitions you must use a pointer to the lock structure (i.e., NAME
   begins with a `*'), because its storage size will not be known outside
   of libc.  */
#define __libc_lock_define(CLASS,NAME) \
  CLASS __libc_lock_t NAME;
#define __libc_rwlock_define(CLASS,NAME) \
  CLASS __libc_rwlock_t NAME;
#define __libc_lock_define_recursive(CLASS,NAME) \
  CLASS __libc_lock_recursive_t NAME;
#define __rtld_lock_define_recursive(CLASS,NAME) \
  CLASS __rtld_lock_recursive_t NAME;

/* Define an initialized lock variable NAME with storage class CLASS.

   For the C library we take a deeper look at the initializer.  For
   this implementation all fields are initialized to zero.  Therefore
   we don't initialize the variable which allows putting it into the
   BSS section.  (Except on PA-RISC and other odd architectures, where
   initialized locks must be set to one due to the lack of normal
   atomic operations.) */

#if __LT_SPINLOCK_INIT == 0
#  define __libc_lock_define_initialized(CLASS,NAME) \
  CLASS __libc_lock_t NAME;
#else
#  define __libc_lock_define_initialized(CLASS,NAME) \
  CLASS __libc_lock_t NAME = PTHREAD_MUTEX_INITIALIZER;
#endif

#define __libc_rwlock_define_initialized(CLASS,NAME) \
  CLASS __libc_rwlock_t NAME = PTHREAD_RWLOCK_INITIALIZER;

/* Define an initialized recursive lock variable NAME with storage
   class CLASS.  */
#define __libc_lock_define_initialized_recursive(CLASS,NAME) \
  CLASS __libc_lock_recursive_t NAME = _LIBC_LOCK_RECURSIVE_INITIALIZER;
#define _LIBC_LOCK_RECURSIVE_INITIALIZER \
  {PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP}

#define __rtld_lock_define_initialized_recursive(CLASS,NAME) \
  CLASS __rtld_lock_recursive_t NAME = _RTLD_LOCK_RECURSIVE_INITIALIZER;
#define _RTLD_LOCK_RECURSIVE_INITIALIZER \
  {PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP}

#if defined _LIBC && defined IS_IN_libpthread
# define __libc_maybe_call(FUNC, ARGS, ELSE) FUNC ARGS
#else
# if defined __PIC__ || (defined _LIBC && defined SHARED)
#  define __libc_maybe_call(FUNC, ARGS, ELSE) \
  (__extension__ ({ __typeof (FUNC) *_fn = (FUNC); \
                    _fn != NULL ? (*_fn) ARGS : ELSE; }))
# else
#  define __libc_maybe_call(FUNC, ARGS, ELSE) \
  (FUNC != NULL ? FUNC ARGS : ELSE)
# endif
#endif
#if defined _LIBC && !defined NOT_IN_libc && defined SHARED
# define __libc_maybe_call2(FUNC, ARGS, ELSE) \
  ({__builtin_expect (__libc_pthread_functions.ptr_##FUNC != NULL, 0) \
    ? __libc_pthread_functions.ptr_##FUNC ARGS : ELSE; })
#else
# define __libc_maybe_call2(FUNC, ARGS, ELSE) __libc_maybe_call (__##FUNC, ARGS, ELSE)
#endif

/* Initialize the named lock variable, leaving it in a consistent, unlocked
   state.  */
#if defined _LIBC && !defined NOT_IN_libc && defined SHARED
#define __libc_lock_init(NAME) \
  ({									      \
    (NAME).__m_count = 0;						      \
    (NAME).__m_owner = NULL;						      \
    (NAME).__m_kind = PTHREAD_MUTEX_TIMED_NP;				      \
    (NAME).__m_lock.__status = 0;					      \
    (NAME).__m_lock.__spinlock = __LT_SPINLOCK_INIT;			      \
    0; })
#else
#define __libc_lock_init(NAME) \
  (__libc_maybe_call2 (pthread_mutex_init, (&(NAME), NULL), 0))
#endif
#define __libc_rwlock_init(NAME) \
  (__libc_maybe_call (__pthread_rwlock_init, (&(NAME), NULL), 0));

/* Same as last but this time we initialize a recursive mutex.  */
#if defined _LIBC && !defined NOT_IN_libc && defined SHARED
#define __libc_lock_init_recursive(NAME) \
  ({									      \
    (NAME).mutex.__m_count = 0;						      \
    (NAME).mutex.__m_owner = NULL;					      \
    (NAME).mutex.__m_kind = PTHREAD_MUTEX_RECURSIVE_NP;			      \
    (NAME).mutex.__m_lock.__status = 0;					      \
    (NAME).mutex.__m_lock.__spinlock = __LT_SPINLOCK_INIT;		      \
    0; })
#else
#define __libc_lock_init_recursive(NAME) \
  do {									      \
    if (__pthread_mutex_init != NULL)					      \
      {									      \
	pthread_mutexattr_t __attr;					      \
	__pthread_mutexattr_init (&__attr);				      \
	__pthread_mutexattr_settype (&__attr, PTHREAD_MUTEX_RECURSIVE_NP); \
	__pthread_mutex_init (&(NAME).mutex, &__attr);			      \
	__pthread_mutexattr_destroy (&__attr);				      \
      }									      \
  } while (0);
#endif
#define __rtld_lock_init_recursive(NAME) \
  __libc_lock_init_recursive (NAME)

/* Finalize the named lock variable, which must be locked.  It cannot be
   used again until __libc_lock_init is called again on it.  This must be
   called on a lock variable before the containing storage is reused.  */
#define __libc_lock_fini(NAME) \
  (__libc_maybe_call2 (pthread_mutex_destroy, (&(NAME)), 0));
#define __libc_rwlock_fini(NAME) \
  (__libc_maybe_call (__pthread_rwlock_destroy, (&(NAME)), 0));

/* Finalize recursive named lock.  */
#define __libc_lock_fini_recursive(NAME) __libc_lock_fini ((NAME).mutex)
#define __rtld_lock_fini_recursive(NAME) __libc_lock_fini_recursive (NAME)

/* Lock the named lock variable.  */
#define __libc_lock_lock(NAME) \
  (__libc_maybe_call2 (pthread_mutex_lock, (&(NAME)), 0));
#define __libc_rwlock_rdlock(NAME) \
  (__libc_maybe_call (__pthread_rwlock_rdlock, (&(NAME)), 0));
#define __libc_rwlock_wrlock(NAME) \
  (__libc_maybe_call (__pthread_rwlock_wrlock, (&(NAME)), 0));

/* Lock the recursive named lock variable.  */
#define __libc_lock_lock_recursive(NAME) __libc_lock_lock ((NAME).mutex)
#define __rtld_lock_lock_recursive(NAME) __libc_lock_lock_recursive (NAME)

/* Try to lock the named lock variable.  */
#define __libc_lock_trylock(NAME) \
  (__libc_maybe_call2 (pthread_mutex_trylock, (&(NAME)), 0))
#define __libc_rwlock_tryrdlock(NAME) \
  (__libc_maybe_call (__pthread_rwlock_tryrdlock, (&(NAME)), 0))
#define __libc_rwlock_trywrlock(NAME) \
  (__libc_maybe_call (__pthread_rwlock_trywrlock, (&(NAME)), 0))

/* Try to lock the recursive named lock variable.  */
#define __libc_lock_trylock_recursive(NAME) __libc_lock_trylock ((NAME).mutex)
#define __rtld_lock_trylock_recursive(NAME) \
  __libc_lock_trylock_recursive (NAME)

/* Unlock the named lock variable.  */
#define __libc_lock_unlock(NAME) \
  (__libc_maybe_call2 (pthread_mutex_unlock, (&(NAME)), 0));
#define __libc_rwlock_unlock(NAME) \
  (__libc_maybe_call (__pthread_rwlock_unlock, (&(NAME)), 0));

/* Unlock the recursive named lock variable.  */
#define __libc_lock_unlock_recursive(NAME) __libc_lock_unlock ((NAME).mutex)
#define __rtld_lock_unlock_recursive(NAME) __libc_lock_unlock_recursive (NAME)


/* Define once control variable.  */
#if PTHREAD_ONCE_INIT == 0
/* Special case for static variables where we can avoid the initialization
   if it is zero.  */
# define __libc_once_define(CLASS, NAME) \
  CLASS pthread_once_t NAME
#else
# define __libc_once_define(CLASS, NAME) \
  CLASS pthread_once_t NAME = PTHREAD_ONCE_INIT
#endif

/* Call handler iff the first call.  */
#define __libc_once(ONCE_CONTROL, INIT_FUNCTION) \
  do {									      \
    if (__pthread_once != NULL)						      \
      __pthread_once (&(ONCE_CONTROL), (INIT_FUNCTION));		      \
    else if ((ONCE_CONTROL) == PTHREAD_ONCE_INIT) {			      \
      INIT_FUNCTION ();							      \
      (ONCE_CONTROL) = 2;						      \
    }									      \
  } while (0)


/* Start critical region with cleanup.  */
#define __libc_cleanup_region_start(DOIT, FCT, ARG) \
  { struct _pthread_cleanup_buffer _buffer;				      \
    int _avail = (DOIT) && _pthread_cleanup_push_defer != NULL;		      \
    if (_avail) {							      \
      _pthread_cleanup_push_defer (&_buffer, (FCT), (ARG));		      \
    }

/* End critical region with cleanup.  */
#define __libc_cleanup_region_end(DOIT) \
    if (_avail) {							      \
      _pthread_cleanup_pop_restore (&_buffer, (DOIT));			      \
    }									      \
  }

/* Sometimes we have to exit the block in the middle.  */
#define __libc_cleanup_end(DOIT) \
    if (_avail) {							      \
      _pthread_cleanup_pop_restore (&_buffer, (DOIT));			      \
    }

#define __libc_cleanup_push(fct, arg) \
  { struct _pthread_cleanup_buffer _buffer;				      \
    int _avail = _pthread_cleanup_push != NULL;				      \
    if (_avail) {							      \
      _pthread_cleanup_push (&_buffer, (fct), (arg));			      \
    }

#define __libc_cleanup_pop(execute) \
    if (_avail) {							      \
      _pthread_cleanup_pop (&_buffer, execute);				      \
    }									      \
  }


/* Create thread-specific key.  */
#define __libc_key_create(KEY, DESTRUCTOR) \
  (__libc_maybe_call (__pthread_key_create, (KEY, DESTRUCTOR), 1))

/* Get thread-specific data.  */
#define __libc_getspecific(KEY) \
  (__libc_maybe_call (__pthread_getspecific, (KEY), NULL))

/* Set thread-specific data.  */
#define __libc_setspecific(KEY, VALUE) \
  (__libc_maybe_call (__pthread_setspecific, (KEY, VALUE), 0))


/* Register handlers to execute before and after `fork'.  */
#define __libc_atfork(PREPARE, PARENT, CHILD) \
  (__libc_maybe_call (__pthread_atfork, (PREPARE, PARENT, CHILD), 0))

/* Functions that are used by this file and are internal to the GNU C
   library.  */

extern int __pthread_mutex_init (pthread_mutex_t *__mutex,
				 __const pthread_mutexattr_t *__mutex_attr);

extern int __pthread_mutex_destroy (pthread_mutex_t *__mutex);

extern int __pthread_mutex_trylock (pthread_mutex_t *__mutex);

extern int __pthread_mutex_lock (pthread_mutex_t *__mutex);

extern int __pthread_mutex_unlock (pthread_mutex_t *__mutex);

extern int __pthread_mutexattr_init (pthread_mutexattr_t *__attr);

extern int __pthread_mutexattr_destroy (pthread_mutexattr_t *__attr);

extern int __pthread_mutexattr_settype (pthread_mutexattr_t *__attr,
					int __kind);

#ifdef __USE_UNIX98
extern int __pthread_rwlock_init (pthread_rwlock_t *__rwlock,
				  __const pthread_rwlockattr_t *__attr);

extern int __pthread_rwlock_destroy (pthread_rwlock_t *__rwlock);

extern int __pthread_rwlock_rdlock (pthread_rwlock_t *__rwlock);

extern int __pthread_rwlock_tryrdlock (pthread_rwlock_t *__rwlock);

extern int __pthread_rwlock_wrlock (pthread_rwlock_t *__rwlock);

extern int __pthread_rwlock_trywrlock (pthread_rwlock_t *__rwlock);

extern int __pthread_rwlock_unlock (pthread_rwlock_t *__rwlock);
#endif

extern int __pthread_key_create (pthread_key_t *__key,
				 void (*__destr_function) (void *));

extern int __pthread_setspecific (pthread_key_t __key,
				  __const void *__pointer);

extern void *__pthread_getspecific (pthread_key_t __key);

extern int __pthread_once (pthread_once_t *__once_control,
			   void (*__init_routine) (void));

extern int __pthread_atfork (void (*__prepare) (void),
			     void (*__parent) (void),
			     void (*__child) (void));



/* Make the pthread functions weak so that we can elide them from
   single-threaded processes.  */
#ifndef __NO_WEAK_PTHREAD_ALIASES
# ifdef weak_extern
#  if _LIBC
#   include <bp-sym.h>
#  else
#   define BP_SYM (sym) sym
#  endif
weak_extern (BP_SYM (__pthread_mutex_init))
weak_extern (BP_SYM (__pthread_mutex_destroy))
weak_extern (BP_SYM (__pthread_mutex_lock))
weak_extern (BP_SYM (__pthread_mutex_trylock))
weak_extern (BP_SYM (__pthread_mutex_unlock))
weak_extern (BP_SYM (__pthread_mutexattr_init))
weak_extern (BP_SYM (__pthread_mutexattr_destroy))
weak_extern (BP_SYM (__pthread_mutexattr_settype))
weak_extern (BP_SYM (__pthread_rwlock_init))
weak_extern (BP_SYM (__pthread_rwlock_destroy))
weak_extern (BP_SYM (__pthread_rwlock_rdlock))
weak_extern (BP_SYM (__pthread_rwlock_tryrdlock))
weak_extern (BP_SYM (__pthread_rwlock_wrlock))
weak_extern (BP_SYM (__pthread_rwlock_trywrlock))
weak_extern (BP_SYM (__pthread_rwlock_unlock))
weak_extern (BP_SYM (__pthread_key_create))
weak_extern (BP_SYM (__pthread_setspecific))
weak_extern (BP_SYM (__pthread_getspecific))
weak_extern (BP_SYM (__pthread_once))
weak_extern (__pthread_initialize)
weak_extern (__pthread_atfork)
weak_extern (BP_SYM (_pthread_cleanup_push))
weak_extern (BP_SYM (_pthread_cleanup_pop))
weak_extern (BP_SYM (_pthread_cleanup_push_defer))
weak_extern (BP_SYM (_pthread_cleanup_pop_restore))
# else
#  pragma weak __pthread_mutex_init
#  pragma weak __pthread_mutex_destroy
#  pragma weak __pthread_mutex_lock
#  pragma weak __pthread_mutex_trylock
#  pragma weak __pthread_mutex_unlock
#  pragma weak __pthread_mutexattr_init
#  pragma weak __pthread_mutexattr_destroy
#  pragma weak __pthread_mutexattr_settype
#  pragma weak __pthread_rwlock_destroy
#  pragma weak __pthread_rwlock_rdlock
#  pragma weak __pthread_rwlock_tryrdlock
#  pragma weak __pthread_rwlock_wrlock
#  pragma weak __pthread_rwlock_trywrlock
#  pragma weak __pthread_rwlock_unlock
#  pragma weak __pthread_key_create
#  pragma weak __pthread_setspecific
#  pragma weak __pthread_getspecific
#  pragma weak __pthread_once
#  pragma weak __pthread_initialize
#  pragma weak __pthread_atfork
#  pragma weak _pthread_cleanup_push_defer
#  pragma weak _pthread_cleanup_pop_restore
#  pragma weak _pthread_cleanup_push
#  pragma weak _pthread_cleanup_pop
# endif
#endif

/* We need portable names for some functions.  E.g., when they are
   used as argument to __libc_cleanup_region_start.  */
#define __libc_mutex_unlock __pthread_mutex_unlock

#endif	/* bits/libc-lock.h */