1 /* Threads compatibility routines for libgcc2 and libobjc. */
2 /* Compile this one with gcc. */
3 /* Copyright (C) 2004, 2005, 2007, 2008, 2009 Free Software Foundation, Inc.
5 This file is part of GCC.
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
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
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.
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/>. */
26 #ifndef GCC_GTHR_POSIX_H
27 #define GCC_GTHR_POSIX_H
29 /* POSIX threads specific definitions.
30 Easy, since the interface is just one-to-one mapping. */
34 /* Some implementations of <pthread.h> require this to be defined. */
42 typedef pthread_key_t __gthread_key_t;
43 typedef pthread_once_t __gthread_once_t;
44 typedef pthread_mutex_t __gthread_mutex_t;
45 typedef pthread_cond_t __gthread_cond_t;
47 /* POSIX like conditional variables are supported. Please look at comments
48 in gthr.h for details. */
49 #define __GTHREAD_HAS_COND 1
54 pthread_mutex_t actual;
55 } __gthread_recursive_mutex_t;
57 #define __GTHREAD_MUTEX_INIT PTHREAD_MUTEX_INITIALIZER
58 #define __GTHREAD_ONCE_INIT PTHREAD_ONCE_INIT
59 #define __GTHREAD_RECURSIVE_MUTEX_INIT_FUNCTION __gthread_recursive_mutex_init_function
60 #define __GTHREAD_COND_INIT PTHREAD_COND_INITIALIZER
62 #if SUPPORTS_WEAK && GTHREAD_USE_WEAK
63 # define __gthrw(name) \
64 static __typeof(name) __gthrw_ ## name __attribute__ ((__weakref__(#name)));
65 # define __gthrw_(name) __gthrw_ ## name
67 # define __gthrw(name)
68 # define __gthrw_(name) name
72 __gthrw(pthread_key_create)
73 __gthrw(pthread_key_delete)
74 __gthrw(pthread_getspecific)
75 __gthrw(pthread_setspecific)
76 __gthrw(pthread_create)
77 __gthrw(pthread_cancel)
80 __gthrw(pthread_mutex_init)
81 __gthrw(pthread_mutex_destroy)
82 __gthrw(pthread_mutex_lock)
83 __gthrw(pthread_mutex_trylock)
84 __gthrw(pthread_mutex_unlock)
85 __gthrw(pthread_mutexattr_init)
86 __gthrw(pthread_mutexattr_destroy)
88 __gthrw(pthread_cond_broadcast)
89 __gthrw(pthread_cond_wait)
91 #if defined(_LIBOBJC) || defined(_LIBOBJC_WEAK)
93 __gthrw(pthread_cond_destroy)
94 __gthrw(pthread_cond_init)
95 __gthrw(pthread_cond_signal)
97 #ifdef _POSIX_PRIORITY_SCHEDULING
98 #ifdef _POSIX_THREAD_PRIORITY_SCHEDULING
99 __gthrw(sched_get_priority_max)
100 __gthrw(sched_get_priority_min)
101 #endif /* _POSIX_THREAD_PRIORITY_SCHEDULING */
102 #endif /* _POSIX_PRIORITY_SCHEDULING */
104 __gthrw(pthread_attr_destroy)
105 __gthrw(pthread_attr_init)
106 __gthrw(pthread_attr_setdetachstate)
107 #ifdef _POSIX_THREAD_PRIORITY_SCHEDULING
108 __gthrw(pthread_getschedparam)
109 __gthrw(pthread_setschedparam)
110 #endif /* _POSIX_THREAD_PRIORITY_SCHEDULING */
111 #endif /* _LIBOBJC || _LIBOBJC_WEAK */
113 #if SUPPORTS_WEAK && GTHREAD_USE_WEAK
115 /* On Solaris 2.6 up to 9, the libc exposes a POSIX threads interface even if
116 -pthreads is not specified. The functions are dummies and most return an
117 error value. However pthread_once returns 0 without invoking the routine
118 it is passed so we cannot pretend that the interface is active if -pthreads
119 is not specified. On Solaris 2.5.1, the interface is not exposed at all so
120 we need to play the usual game with weak symbols. On Solaris 10 and up, a
121 working interface is always exposed. On FreeBSD 6 and later, libc also
122 exposes a dummy POSIX threads interface, similar to what Solaris 2.6 up
123 to 9 does. FreeBSD >= 700014 even provides a pthread_cancel stub in libc,
124 which means the alternate __gthread_active_p below cannot be used there. */
126 #if defined(__FreeBSD__) || (defined(__sun) && defined(__svr4__))
128 static volatile int __gthread_active = -1;
131 __gthread_trigger (void)
133 __gthread_active = 1;
137 __gthread_active_p (void)
139 static pthread_mutex_t __gthread_active_mutex = PTHREAD_MUTEX_INITIALIZER;
140 static pthread_once_t __gthread_active_once = PTHREAD_ONCE_INIT;
142 /* Avoid reading __gthread_active twice on the main code path. */
143 int __gthread_active_latest_value = __gthread_active;
145 /* This test is not protected to avoid taking a lock on the main code
146 path so every update of __gthread_active in a threaded program must
147 be atomic with regard to the result of the test. */
148 if (__builtin_expect (__gthread_active_latest_value < 0, 0))
150 if (__gthrw_(pthread_once))
152 /* If this really is a threaded program, then we must ensure that
153 __gthread_active has been set to 1 before exiting this block. */
154 __gthrw_(pthread_mutex_lock) (&__gthread_active_mutex);
155 __gthrw_(pthread_once) (&__gthread_active_once, __gthread_trigger);
156 __gthrw_(pthread_mutex_unlock) (&__gthread_active_mutex);
159 /* Make sure we'll never enter this block again. */
160 if (__gthread_active < 0)
161 __gthread_active = 0;
163 __gthread_active_latest_value = __gthread_active;
166 return __gthread_active_latest_value != 0;
169 #else /* neither FreeBSD nor Solaris */
172 __gthread_active_p (void)
174 static void *const __gthread_active_ptr
175 = __extension__ (void *) &__gthrw_(pthread_cancel);
176 return __gthread_active_ptr != 0;
179 #endif /* FreeBSD or Solaris */
181 #else /* not SUPPORTS_WEAK */
183 /* Similar to Solaris, HP-UX 11 for PA-RISC provides stubs for pthread
184 calls in shared flavors of the HP-UX C library. Most of the stubs
185 have no functionality. The details are described in the "libc cumulative
186 patch" for each subversion of HP-UX 11. There are two special interfaces
187 provided for checking whether an application is linked to a pthread
188 library or not. However, these interfaces aren't available in early
189 libc versions. We also can't use pthread_once as some libc versions
190 call the init function. So, we use pthread_create to check whether it
191 is possible to create a thread or not. The stub implementation returns
192 the error number ENOSYS. */
194 #if defined(__hppa__) && defined(__hpux__)
198 static volatile int __gthread_active = -1;
200 static void __gthread_active_init (void) __attribute__((noinline));
202 __gthread_active_init (void)
204 static pthread_mutex_t __gthread_active_mutex = PTHREAD_MUTEX_INITIALIZER;
207 __gthrw_(pthread_mutex_lock) (&__gthread_active_mutex);
208 if (__gthread_active < 0)
210 pthread_default_stacksize_np (0, &__s);
211 __gthread_active = __s ? 1 : 0;
213 __gthrw_(pthread_mutex_unlock) (&__gthread_active_mutex);
217 __gthread_active_p (void)
219 /* Avoid reading __gthread_active twice on the main code path. */
220 int __gthread_active_latest_value = __gthread_active;
222 /* This test is not protected to avoid taking a lock on the main code
223 path so every update of __gthread_active in a threaded program must
224 be atomic with regard to the result of the test. */
225 if (__builtin_expect (__gthread_active_latest_value < 0, 0))
227 __gthread_active_init ();
228 __gthread_active_latest_value = __gthread_active;
231 return __gthread_active_latest_value != 0;
234 #else /* not hppa-hpux */
237 __gthread_active_p (void)
242 #endif /* hppa-hpux */
244 #endif /* SUPPORTS_WEAK */
248 /* This is the config.h file in libobjc/ */
255 /* Key structure for maintaining thread specific storage */
256 static pthread_key_t _objc_thread_storage;
257 static pthread_attr_t _objc_thread_attribs;
259 /* Thread local storage for a single thread */
260 static void *thread_local_storage = NULL;
262 /* Backend initialization functions */
264 /* Initialize the threads subsystem. */
266 __gthread_objc_init_thread_system (void)
268 if (__gthread_active_p ())
270 /* Initialize the thread storage key. */
271 if (__gthrw_(pthread_key_create) (&_objc_thread_storage, NULL) == 0)
273 /* The normal default detach state for threads is
274 * PTHREAD_CREATE_JOINABLE which causes threads to not die
275 * when you think they should. */
276 if (__gthrw_(pthread_attr_init) (&_objc_thread_attribs) == 0
277 && __gthrw_(pthread_attr_setdetachstate) (&_objc_thread_attribs,
278 PTHREAD_CREATE_DETACHED) == 0)
286 /* Close the threads subsystem. */
288 __gthread_objc_close_thread_system (void)
290 if (__gthread_active_p ()
291 && __gthrw_(pthread_key_delete) (_objc_thread_storage) == 0
292 && __gthrw_(pthread_attr_destroy) (&_objc_thread_attribs) == 0)
298 /* Backend thread functions */
300 /* Create a new thread of execution. */
301 static inline objc_thread_t
302 __gthread_objc_thread_detach (void (*func)(void *), void *arg)
304 objc_thread_t thread_id;
305 pthread_t new_thread_handle;
307 if (!__gthread_active_p ())
310 if (!(__gthrw_(pthread_create) (&new_thread_handle, NULL, (void *) func, arg)))
311 thread_id = (objc_thread_t) new_thread_handle;
318 /* Set the current thread's priority. */
320 __gthread_objc_thread_set_priority (int priority)
322 if (!__gthread_active_p ())
326 #ifdef _POSIX_PRIORITY_SCHEDULING
327 #ifdef _POSIX_THREAD_PRIORITY_SCHEDULING
328 pthread_t thread_id = __gthrw_(pthread_self) ();
330 struct sched_param params;
331 int priority_min, priority_max;
333 if (__gthrw_(pthread_getschedparam) (thread_id, &policy, ¶ms) == 0)
335 if ((priority_max = __gthrw_(sched_get_priority_max) (policy)) == -1)
338 if ((priority_min = __gthrw_(sched_get_priority_min) (policy)) == -1)
341 if (priority > priority_max)
342 priority = priority_max;
343 else if (priority < priority_min)
344 priority = priority_min;
345 params.sched_priority = priority;
348 * The solaris 7 and several other man pages incorrectly state that
349 * this should be a pointer to policy but pthread.h is universally
352 if (__gthrw_(pthread_setschedparam) (thread_id, policy, ¶ms) == 0)
355 #endif /* _POSIX_THREAD_PRIORITY_SCHEDULING */
356 #endif /* _POSIX_PRIORITY_SCHEDULING */
361 /* Return the current thread's priority. */
363 __gthread_objc_thread_get_priority (void)
365 #ifdef _POSIX_PRIORITY_SCHEDULING
366 #ifdef _POSIX_THREAD_PRIORITY_SCHEDULING
367 if (__gthread_active_p ())
370 struct sched_param params;
372 if (__gthrw_(pthread_getschedparam) (__gthrw_(pthread_self) (), &policy, ¶ms) == 0)
373 return params.sched_priority;
378 #endif /* _POSIX_THREAD_PRIORITY_SCHEDULING */
379 #endif /* _POSIX_PRIORITY_SCHEDULING */
380 return OBJC_THREAD_INTERACTIVE_PRIORITY;
383 /* Yield our process time to another thread. */
385 __gthread_objc_thread_yield (void)
387 if (__gthread_active_p ())
388 __gthrw_(sched_yield) ();
391 /* Terminate the current thread. */
393 __gthread_objc_thread_exit (void)
395 if (__gthread_active_p ())
396 /* exit the thread */
397 __gthrw_(pthread_exit) (&__objc_thread_exit_status);
399 /* Failed if we reached here */
403 /* Returns an integer value which uniquely describes a thread. */
404 static inline objc_thread_t
405 __gthread_objc_thread_id (void)
407 if (__gthread_active_p ())
408 return (objc_thread_t) __gthrw_(pthread_self) ();
410 return (objc_thread_t) 1;
413 /* Sets the thread's local storage pointer. */
415 __gthread_objc_thread_set_data (void *value)
417 if (__gthread_active_p ())
418 return __gthrw_(pthread_setspecific) (_objc_thread_storage, value);
421 thread_local_storage = value;
426 /* Returns the thread's local storage pointer. */
428 __gthread_objc_thread_get_data (void)
430 if (__gthread_active_p ())
431 return __gthrw_(pthread_getspecific) (_objc_thread_storage);
433 return thread_local_storage;
436 /* Backend mutex functions */
438 /* Allocate a mutex. */
440 __gthread_objc_mutex_allocate (objc_mutex_t mutex)
442 if (__gthread_active_p ())
444 mutex->backend = objc_malloc (sizeof (pthread_mutex_t));
446 if (__gthrw_(pthread_mutex_init) ((pthread_mutex_t *) mutex->backend, NULL))
448 objc_free (mutex->backend);
449 mutex->backend = NULL;
457 /* Deallocate a mutex. */
459 __gthread_objc_mutex_deallocate (objc_mutex_t mutex)
461 if (__gthread_active_p ())
466 * Posix Threads specifically require that the thread be unlocked
467 * for __gthrw_(pthread_mutex_destroy) to work.
472 count = __gthrw_(pthread_mutex_unlock) ((pthread_mutex_t *) mutex->backend);
478 if (__gthrw_(pthread_mutex_destroy) ((pthread_mutex_t *) mutex->backend))
481 objc_free (mutex->backend);
482 mutex->backend = NULL;
487 /* Grab a lock on a mutex. */
489 __gthread_objc_mutex_lock (objc_mutex_t mutex)
491 if (__gthread_active_p ()
492 && __gthrw_(pthread_mutex_lock) ((pthread_mutex_t *) mutex->backend) != 0)
500 /* Try to grab a lock on a mutex. */
502 __gthread_objc_mutex_trylock (objc_mutex_t mutex)
504 if (__gthread_active_p ()
505 && __gthrw_(pthread_mutex_trylock) ((pthread_mutex_t *) mutex->backend) != 0)
513 /* Unlock the mutex */
515 __gthread_objc_mutex_unlock (objc_mutex_t mutex)
517 if (__gthread_active_p ()
518 && __gthrw_(pthread_mutex_unlock) ((pthread_mutex_t *) mutex->backend) != 0)
526 /* Backend condition mutex functions */
528 /* Allocate a condition. */
530 __gthread_objc_condition_allocate (objc_condition_t condition)
532 if (__gthread_active_p ())
534 condition->backend = objc_malloc (sizeof (pthread_cond_t));
536 if (__gthrw_(pthread_cond_init) ((pthread_cond_t *) condition->backend, NULL))
538 objc_free (condition->backend);
539 condition->backend = NULL;
547 /* Deallocate a condition. */
549 __gthread_objc_condition_deallocate (objc_condition_t condition)
551 if (__gthread_active_p ())
553 if (__gthrw_(pthread_cond_destroy) ((pthread_cond_t *) condition->backend))
556 objc_free (condition->backend);
557 condition->backend = NULL;
562 /* Wait on the condition */
564 __gthread_objc_condition_wait (objc_condition_t condition, objc_mutex_t mutex)
566 if (__gthread_active_p ())
567 return __gthrw_(pthread_cond_wait) ((pthread_cond_t *) condition->backend,
568 (pthread_mutex_t *) mutex->backend);
573 /* Wake up all threads waiting on this condition. */
575 __gthread_objc_condition_broadcast (objc_condition_t condition)
577 if (__gthread_active_p ())
578 return __gthrw_(pthread_cond_broadcast) ((pthread_cond_t *) condition->backend);
583 /* Wake up one thread waiting on this condition. */
585 __gthread_objc_condition_signal (objc_condition_t condition)
587 if (__gthread_active_p ())
588 return __gthrw_(pthread_cond_signal) ((pthread_cond_t *) condition->backend);
596 __gthread_once (__gthread_once_t *__once, void (*__func) (void))
598 if (__gthread_active_p ())
599 return __gthrw_(pthread_once) (__once, __func);
605 __gthread_key_create (__gthread_key_t *__key, void (*__dtor) (void *))
607 return __gthrw_(pthread_key_create) (__key, __dtor);
611 __gthread_key_delete (__gthread_key_t __key)
613 return __gthrw_(pthread_key_delete) (__key);
617 __gthread_getspecific (__gthread_key_t __key)
619 return __gthrw_(pthread_getspecific) (__key);
623 __gthread_setspecific (__gthread_key_t __key, const void *__ptr)
625 return __gthrw_(pthread_setspecific) (__key, __ptr);
629 __gthread_mutex_destroy (__gthread_mutex_t *__mutex)
631 if (__gthread_active_p ())
632 return __gthrw_(pthread_mutex_destroy) (__mutex);
638 __gthread_mutex_lock (__gthread_mutex_t *__mutex)
640 if (__gthread_active_p ())
641 return __gthrw_(pthread_mutex_lock) (__mutex);
647 __gthread_mutex_trylock (__gthread_mutex_t *__mutex)
649 if (__gthread_active_p ())
650 return __gthrw_(pthread_mutex_trylock) (__mutex);
656 __gthread_mutex_unlock (__gthread_mutex_t *__mutex)
658 if (__gthread_active_p ())
659 return __gthrw_(pthread_mutex_unlock) (__mutex);
665 __gthread_recursive_mutex_init_function (__gthread_recursive_mutex_t *__mutex)
668 __mutex->owner = (pthread_t) 0;
669 return __gthrw_(pthread_mutex_init) (&__mutex->actual, NULL);
673 __gthread_recursive_mutex_lock (__gthread_recursive_mutex_t *__mutex)
675 if (__gthread_active_p ())
677 pthread_t __me = __gthrw_(pthread_self) ();
679 if (__mutex->owner != __me)
681 __gthrw_(pthread_mutex_lock) (&__mutex->actual);
682 __mutex->owner = __me;
691 __gthread_recursive_mutex_trylock (__gthread_recursive_mutex_t *__mutex)
693 if (__gthread_active_p ())
695 pthread_t __me = __gthrw_(pthread_self) ();
697 if (__mutex->owner != __me)
699 if (__gthrw_(pthread_mutex_trylock) (&__mutex->actual))
701 __mutex->owner = __me;
710 __gthread_recursive_mutex_unlock (__gthread_recursive_mutex_t *__mutex)
712 if (__gthread_active_p ())
714 if (--__mutex->depth == 0)
716 __mutex->owner = (pthread_t) 0;
717 __gthrw_(pthread_mutex_unlock) (&__mutex->actual);
724 __gthread_cond_broadcast (__gthread_cond_t *__cond)
726 return __gthrw_(pthread_cond_broadcast) (__cond);
730 __gthread_cond_wait (__gthread_cond_t *__cond, __gthread_mutex_t *__mutex)
732 return __gthrw_(pthread_cond_wait) (__cond, __mutex);
736 __gthread_cond_wait_recursive (__gthread_cond_t *__cond,
737 __gthread_recursive_mutex_t *__mutex)
739 return __gthrw_(pthread_cond_wait) (__cond, &__mutex->actual);
742 #endif /* _LIBOBJC */
744 #endif /* ! GCC_GTHR_POSIX_H */