libgcc/gthr.h

   1 /* Threads compatibility routines for libgcc2.  */
   2 /* Compile this one with gcc.  */
   3 /* Copyright (C) 1997-2023 Free Software Foundation, Inc.
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 3, or (at your option) any later
  10 version.
  11
  12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 for more details.
  16
  17 Under Section 7 of GPL version 3, you are granted additional
  18 permissions described in the GCC Runtime Library Exception, version
  19 3.1, as published by the Free Software Foundation.
  20
  21 You should have received a copy of the GNU General Public License and
  22 a copy of the GCC Runtime Library Exception along with this program;
  23 see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  24 <http://www.gnu.org/licenses/>.  */
  25
  26 #ifndef GCC_GTHR_H
  27 #define GCC_GTHR_H
  28
  29 #ifndef HIDE_EXPORTS
  30 #pragma GCC visibility push(default)
  31 #endif
  32
  33 /* If this file is compiled with threads support, it must
  34        #define __GTHREADS 1
  35    to indicate that threads support is present.  Also it has define
  36    function
  37      int __gthread_active_p ()
  38    that returns 1 if thread system is active, 0 if not.
  39
  40    The threads interface must define the following types:
  41      __gthread_key_t
  42      __gthread_once_t
  43      __gthread_mutex_t
  44      __gthread_recursive_mutex_t
  45
  46    The threads interface must define the following macros:
  47
  48      __GTHREAD_ONCE_INIT
  49                 to initialize __gthread_once_t
  50      __GTHREAD_MUTEX_INIT
  51                 to initialize __gthread_mutex_t to get a fast
  52                 non-recursive mutex.
  53      __GTHREAD_MUTEX_INIT_FUNCTION
  54                 to initialize __gthread_mutex_t to get a fast
  55                 non-recursive mutex.
  56                 Define this to a function which looks like this:
  57                   void __GTHREAD_MUTEX_INIT_FUNCTION (__gthread_mutex_t *)
  58                 Some systems can't initialize a mutex without a
  59                 function call.  Don't define __GTHREAD_MUTEX_INIT in this case.
  60      __GTHREAD_RECURSIVE_MUTEX_INIT
  61      __GTHREAD_RECURSIVE_MUTEX_INIT_FUNCTION
  62                 as above, but for a recursive mutex.
  63
  64    The threads interface must define the following static functions:
  65
  66      int __gthread_once (__gthread_once_t *once, void (*func) ())
  67
  68      int __gthread_key_create (__gthread_key_t *keyp, void (*dtor) (void *))
  69      int __gthread_key_delete (__gthread_key_t key)
  70
  71      void *__gthread_getspecific (__gthread_key_t key)
  72      int __gthread_setspecific (__gthread_key_t key, const void *ptr)
  73
  74      int __gthread_mutex_destroy (__gthread_mutex_t *mutex);
  75      int __gthread_recursive_mutex_destroy (__gthread_recursive_mutex_t *mutex);
  76
  77      int __gthread_mutex_lock (__gthread_mutex_t *mutex);
  78      int __gthread_mutex_trylock (__gthread_mutex_t *mutex);
  79      int __gthread_mutex_unlock (__gthread_mutex_t *mutex);
  80
  81      int __gthread_recursive_mutex_lock (__gthread_recursive_mutex_t *mutex);
  82      int __gthread_recursive_mutex_trylock (__gthread_recursive_mutex_t *mutex);
  83      int __gthread_recursive_mutex_unlock (__gthread_recursive_mutex_t *mutex);
  84
  85    The following are supported in POSIX threads only. They are required to
  86    fix a deadlock in static initialization inside libsupc++. The header file
  87    gthr-posix.h defines a symbol __GTHREAD_HAS_COND to signify that these extra
  88    features are supported.
  89
  90    Types:
  91      __gthread_cond_t
  92
  93    Macros:
  94      __GTHREAD_COND_INIT
  95      __GTHREAD_COND_INIT_FUNCTION
  96
  97    Interface:
  98      int __gthread_cond_broadcast (__gthread_cond_t *cond);
  99      int __gthread_cond_wait (__gthread_cond_t *cond, __gthread_mutex_t *mutex);
 100      int __gthread_cond_wait_recursive (__gthread_cond_t *cond,
 101                                         __gthread_recursive_mutex_t *mutex);
 102
 103    All functions returning int should return zero on success or the error
 104    number.  If the operation is not supported, -1 is returned.
 105
 106    If the following are also defined, you should
 107      #define __GTHREADS_CXX0X 1
 108    to enable the c++0x thread library.
 109
 110    Types:
 111      __gthread_t
 112      __gthread_time_t
 113
 114    Interface:
 115      int __gthread_create (__gthread_t *thread, void *(*func) (void*),
 116                            void *args);
 117      int __gthread_join (__gthread_t thread, void **value_ptr);
 118      int __gthread_detach (__gthread_t thread);
 119      int __gthread_equal (__gthread_t t1, __gthread_t t2);
 120      __gthread_t __gthread_self (void);
 121      int __gthread_yield (void);
 122
 123      int __gthread_mutex_timedlock (__gthread_mutex_t *m,
 124                                     const __gthread_time_t *abs_timeout);
 125      int __gthread_recursive_mutex_timedlock (__gthread_recursive_mutex_t *m,
 126                                           const __gthread_time_t *abs_time);
 127
 128      int __gthread_cond_signal (__gthread_cond_t *cond);
 129      int __gthread_cond_timedwait (__gthread_cond_t *cond,
 130                                    __gthread_mutex_t *mutex,
 131                                    const __gthread_time_t *abs_timeout);
 132
 133 */
 134
 135 #if SUPPORTS_WEAK
 136 /* The pe-coff weak support isn't fully compatible to ELF's weak.
 137    For static libraries it might would work, but as we need to deal
 138    with shared versions too, we disable it for mingw-targets.  */
 139 #ifdef __MINGW32__
 140 #undef GTHREAD_USE_WEAK
 141 #define GTHREAD_USE_WEAK 0
 142 #endif
 143
 144 #ifndef GTHREAD_USE_WEAK
 145 #define GTHREAD_USE_WEAK 1
 146 #endif
 147 #endif
 148 #include "gthr-default.h"
 149
 150 #ifndef HIDE_EXPORTS
 151 #pragma GCC visibility pop
 152 #endif
 153
 154 #endif /* ! GCC_GTHR_H */