bits/libc-lock.h

   1 /* libc-internal interface for mutex locks.  Stub version.
   2    Copyright (C) 1996,97,99,2000,01,02 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, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #ifndef _BITS_LIBC_LOCK_H
  21 #define _BITS_LIBC_LOCK_H 1
  22
  23
  24 /* Define a lock variable NAME with storage class CLASS.  The lock must be
  25    initialized with __libc_lock_init before it can be used (or define it
  26    with __libc_lock_define_initialized, below).  Use `extern' for CLASS to
  27    declare a lock defined in another module.  In public structure
  28    definitions you must use a pointer to the lock structure (i.e., NAME
  29    begins with a `*'), because its storage size will not be known outside
  30    of libc.  */
  31 #define __libc_lock_define(CLASS,NAME)
  32 #define __libc_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
  43 /* Initialize the named lock variable, leaving it in a consistent, unlocked
  44    state.  */
  45 #define __libc_lock_init(NAME)
  46 #define __libc_rwlock_init(NAME)
  47
  48 /* Same as last but this time we initialize a recursive mutex.  */
  49 #define __libc_lock_init_recursive(NAME)
  50
  51 /* Finalize the named lock variable, which must be locked.  It cannot be
  52    used again until __libc_lock_init is called again on it.  This must be
  53    called on a lock variable before the containing storage is reused.  */
  54 #define __libc_lock_fini(NAME)
  55 #define __libc_rwlock_fini(NAME)
  56
  57 /* Finalize recursive named lock.  */
  58 #define __libc_lock_fini_recursive(NAME)
  59
  60 /* Lock the named lock variable.  */
  61 #define __libc_lock_lock(NAME)
  62 #define __libc_rwlock_rdlock(NAME)
  63 #define __libc_rwlock_wrlock(NAME)
  64
  65 /* Lock the recursive named lock variable.  */
  66 #define __libc_lock_lock_recursive(NAME)
  67
  68 /* Try to lock the named lock variable.  */
  69 #define __libc_lock_trylock(NAME) 0
  70 #define __libc_rwlock_tryrdlock(NAME) 0
  71 #define __libc_rwlock_trywrlock(NAME) 0
  72
  73 /* Try to lock the recursive named lock variable.  */
  74 #define __libc_lock_trylock_recursive(NAME) 0
  75
  76 /* Unlock the named lock variable.  */
  77 #define __libc_lock_unlock(NAME)
  78 #define __libc_rwlock_unlock(NAME)
  79
  80 /* Unlock the recursive named lock variable.  */
  81 #define __libc_lock_unlock_recursive(NAME)
  82
  83
  84 /* Define once control variable.  */
  85 #define __libc_once_define(CLASS, NAME) CLASS int NAME = 0
  86
  87 /* Call handler iff the first call.  */
  88 #define __libc_once(ONCE_CONTROL, INIT_FUNCTION) \
  89   do {                                                                        \
  90     if ((ONCE_CONTROL) == 0) {                                                \
  91       INIT_FUNCTION ();                                                       \
  92       (ONCE_CONTROL) = 1;                                                     \
  93     }                                                                         \
  94   } while (0)
  95
  96
  97 /* Start a critical region with a cleanup function */
  98 #define __libc_cleanup_region_start(DOIT, FCT, ARG)                         \
  99 {                                                                           \
 100   typeof (***(FCT)) *__save_FCT = (DOIT) ? (FCT) : 0;                       \
 101   typeof (ARG) __save_ARG = ARG;                                            \
 102   /* close brace is in __libc_cleanup_region_end below. */
 103
 104 /* End a critical region started with __libc_cleanup_region_start. */
 105 #define __libc_cleanup_region_end(DOIT)                                     \
 106   if ((DOIT) && __save_FCT != 0)                                            \
 107     (*__save_FCT)(__save_ARG);                                              \
 108 }
 109
 110 /* Sometimes we have to exit the block in the middle.  */
 111 #define __libc_cleanup_end(DOIT)                                            \
 112   if ((DOIT) && __save_FCT != 0)                                            \
 113     (*__save_FCT)(__save_ARG);                                              \
 114
 115
 116 /* We need portable names for some of the functions.  */
 117 #define __libc_mutex_unlock
 118
 119 /* Type for key of thread specific data.  */
 120 typedef int __libc_key_t;
 121
 122 /* Create key for thread specific data.  */
 123 #define __libc_key_create(KEY,DEST) -1
 124
 125 /* Set thread-specific data associated with KEY to VAL.  */
 126 #define __libc_setspecific(KEY,VAL) ((void)0)
 127
 128 /* Get thread-specific data associated with KEY.  */
 129 #define __libc_getspecific(KEY) 0
 130
 131 #endif  /* bits/libc-lock.h */