1/* libc-internal interface for mutex locks.  Stub version.
  2   Copyright (C) 1996-2025 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
  7   License as published by the Free Software Foundation; either
  8   version 2.1 of the 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; if not, see
 17   <https://www.gnu.org/licenses/>.  */
 18
 19#ifndef _LIBC_LOCK_H
 20#define _LIBC_LOCK_H 1
 21
 22
 23/* Define a lock variable NAME with storage class CLASS.  The lock must be
 24   initialized with __libc_lock_init before it can be used (or define it
 25   with __libc_lock_define_initialized, below).  Use `extern' for CLASS to
 26   declare a lock defined in another module.  In public structure
 27   definitions you must use a pointer to the lock structure (i.e., NAME
 28   begins with a `*'), because its storage size will not be known outside
 29   of libc.  */
 30#define __libc_lock_define(CLASS,NAME)
 31#define __libc_lock_define_recursive(CLASS,NAME)
 32#define __rtld_lock_define_recursive(CLASS,NAME)
 33#define __libc_rwlock_define(CLASS,NAME)
 34
 35/* Define an initialized lock variable NAME with storage class CLASS.  */
 36#define __libc_lock_define_initialized(CLASS,NAME)
 37#define __libc_rwlock_define_initialized(CLASS,NAME)
 38
 39/* Define an initialized recursive lock variable NAME with storage
 40   class CLASS.  */
 41#define __libc_lock_define_initialized_recursive(CLASS,NAME)
 42#define __rtld_lock_define_initialized_recursive(CLASS,NAME)
 43
 44/* Initialize the named lock variable, leaving it in a consistent, unlocked
 45   state.  */
 46#define __libc_lock_init(NAME)
 47#define __rtld_lock_initialize(NAME)
 48#define __libc_rwlock_init(NAME)
 49
 50/* Same as last but this time we initialize a recursive mutex.  */
 51#define __libc_lock_init_recursive(NAME)
 52
 53/* Finalize the named lock variable, which must be locked.  It cannot be
 54   used again until __libc_lock_init is called again on it.  This must be
 55   called on a lock variable before the containing storage is reused.  */
 56#define __libc_lock_fini(NAME)
 57#define __libc_rwlock_fini(NAME)
 58
 59/* Finalize recursive named lock.  */
 60#define __libc_lock_fini_recursive(NAME)
 61
 62/* Lock the named lock variable.  */
 63#define __libc_lock_lock(NAME)
 64#define __libc_rwlock_rdlock(NAME)
 65#define __libc_rwlock_wrlock(NAME)
 66
 67/* Lock the recursive named lock variable.  */
 68#define __libc_lock_lock_recursive(NAME)
 69#define __rtld_lock_lock_recursive(NAME)
 70
 71/* Try to lock the named lock variable.  */
 72#define __libc_lock_trylock(NAME) 0
 73#define __libc_rwlock_tryrdlock(NAME) 0
 74#define __libc_rwlock_trywrlock(NAME) 0
 75
 76/* Try to lock the recursive named lock variable.  */
 77#define __libc_lock_trylock_recursive(NAME) 0
 78
 79/* Unlock the named lock variable.  */
 80#define __libc_lock_unlock(NAME)
 81#define __libc_rwlock_unlock(NAME)
 82
 83/* Unlock the recursive named lock variable.  */
 84#define __libc_lock_unlock_recursive(NAME)
 85#define __rtld_lock_unlock_recursive(NAME)
 86
 87
 88/* Define once control variable.  */
 89#define __libc_once_define(CLASS, NAME) CLASS int NAME = 0
 90
 91/* Call handler iff the first call.  */
 92#define __libc_once(ONCE_CONTROL, INIT_FUNCTION) \
 93  do {									      \
 94    if ((ONCE_CONTROL) == 0) {						      \
 95      INIT_FUNCTION ();							      \
 96      (ONCE_CONTROL) = 1;						      \
 97    }									      \
 98  } while (0)
 99
100/* Get once control variable.  */
101#define __libc_once_get(ONCE_CONTROL) \
102  ((ONCE_CONTROL) == 1)
103
104/* Start a critical region with a cleanup function */
105#define __libc_cleanup_region_start(DOIT, FCT, ARG)			    \
106{									    \
107  typeof (***(FCT)) *__save_FCT = (DOIT) ? (FCT) : 0;			    \
108  typeof (ARG) __save_ARG = ARG;					    \
109  /* close brace is in __libc_cleanup_region_end below. */
110
111/* End a critical region started with __libc_cleanup_region_start. */
112#define __libc_cleanup_region_end(DOIT)					    \
113  if ((DOIT) && __save_FCT != 0)					    \
114    (*__save_FCT)(__save_ARG);						    \
115}
116
117/* Sometimes we have to exit the block in the middle.  */
118#define __libc_cleanup_end(DOIT)					    \
119  if ((DOIT) && __save_FCT != 0)					    \
120    (*__save_FCT)(__save_ARG);						    \
121
122#define __libc_cleanup_push(fct, arg) __libc_cleanup_region_start (1, fct, arg)
123#define __libc_cleanup_pop(execute) __libc_cleanup_region_end (execute)
124
125/* We need portable names for some of the functions.  */
126#define __libc_mutex_unlock
127
128#endif	/* libc-lock.h */