libstdc++
gthr.h
1 /* Threads compatibility routines for libgcc2. */
2 /* Compile this one with gcc. */
3 /* Copyright (C) 1997-2022 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 _GLIBCXX_GCC_GTHR_H
27 #define _GLIBCXX_GCC_GTHR_H
28 
29 #ifndef _GLIBCXX_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 __GXX_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 _GLIBCXX_GTHREAD_USE_WEAK
141 #define _GLIBCXX_GTHREAD_USE_WEAK 0
142 #endif
143 
144 #ifndef _GLIBCXX_GTHREAD_USE_WEAK
145 #define _GLIBCXX_GTHREAD_USE_WEAK 1
146 #endif
147 #endif
148 #include <bits/gthr-default.h>
149 
150 #ifndef _GLIBCXX_HIDE_EXPORTS
151 #pragma GCC visibility pop
152 #endif
153 
154 #endif /* ! _GLIBCXX_GCC_GTHR_H */