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/* Threads compatibility routines for libgcc2 and libobjc. */
/* Compile this one with gcc. */
/* Copyright (C) 2004, 2005, 2007, 2008, 2009 Free Software Foundation, Inc.
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.
You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<http://www.gnu.org/licenses/>. */
#ifndef GCC_GTHR_POSIX_H
#define GCC_GTHR_POSIX_H
/* POSIX threads specific definitions.
Easy, since the interface is just one-to-one mapping. */
#define __GTHREADS 1
/* Some implementations of <pthread.h> require this to be defined. */
#ifndef _REENTRANT
#define _REENTRANT 1
#endif
#include <pthread.h>
#include <unistd.h>
typedef pthread_key_t __gthread_key_t;
typedef pthread_once_t __gthread_once_t;
typedef pthread_mutex_t __gthread_mutex_t;
typedef pthread_cond_t __gthread_cond_t;
/* POSIX like conditional variables are supported. Please look at comments
in gthr.h for details. */
#define __GTHREAD_HAS_COND 1
typedef struct {
long depth;
pthread_t owner;
pthread_mutex_t actual;
} __gthread_recursive_mutex_t;
#define __GTHREAD_MUTEX_INIT PTHREAD_MUTEX_INITIALIZER
#define __GTHREAD_ONCE_INIT PTHREAD_ONCE_INIT
#define __GTHREAD_RECURSIVE_MUTEX_INIT_FUNCTION __gthread_recursive_mutex_init_function
#define __GTHREAD_COND_INIT PTHREAD_COND_INITIALIZER
#if SUPPORTS_WEAK && GTHREAD_USE_WEAK
# define __gthrw(name) \
static __typeof(name) __gthrw_ ## name __attribute__ ((__weakref__(#name)));
# define __gthrw_(name) __gthrw_ ## name
#else
# define __gthrw(name)
# define __gthrw_(name) name
#endif
__gthrw(pthread_once)
__gthrw(pthread_key_create)
__gthrw(pthread_key_delete)
__gthrw(pthread_getspecific)
__gthrw(pthread_setspecific)
__gthrw(pthread_create)
__gthrw(pthread_cancel)
__gthrw(pthread_self)
__gthrw(pthread_mutex_init)
__gthrw(pthread_mutex_destroy)
__gthrw(pthread_mutex_lock)
__gthrw(pthread_mutex_trylock)
__gthrw(pthread_mutex_unlock)
__gthrw(pthread_mutexattr_init)
__gthrw(pthread_mutexattr_destroy)
__gthrw(pthread_cond_broadcast)
__gthrw(pthread_cond_wait)
#if defined(_LIBOBJC) || defined(_LIBOBJC_WEAK)
/* Objective-C. */
__gthrw(pthread_cond_destroy)
__gthrw(pthread_cond_init)
__gthrw(pthread_cond_signal)
__gthrw(pthread_exit)
#ifdef _POSIX_PRIORITY_SCHEDULING
#ifdef _POSIX_THREAD_PRIORITY_SCHEDULING
__gthrw(sched_get_priority_max)
__gthrw(sched_get_priority_min)
#endif /* _POSIX_THREAD_PRIORITY_SCHEDULING */
#endif /* _POSIX_PRIORITY_SCHEDULING */
__gthrw(sched_yield)
__gthrw(pthread_attr_destroy)
__gthrw(pthread_attr_init)
__gthrw(pthread_attr_setdetachstate)
#ifdef _POSIX_THREAD_PRIORITY_SCHEDULING
__gthrw(pthread_getschedparam)
__gthrw(pthread_setschedparam)
#endif /* _POSIX_THREAD_PRIORITY_SCHEDULING */
#endif /* _LIBOBJC || _LIBOBJC_WEAK */
#if SUPPORTS_WEAK && GTHREAD_USE_WEAK
/* On Solaris 2.6 up to 9, the libc exposes a POSIX threads interface even if
-pthreads is not specified. The functions are dummies and most return an
error value. However pthread_once returns 0 without invoking the routine
it is passed so we cannot pretend that the interface is active if -pthreads
is not specified. On Solaris 2.5.1, the interface is not exposed at all so
we need to play the usual game with weak symbols. On Solaris 10 and up, a
working interface is always exposed. On FreeBSD 6 and later, libc also
exposes a dummy POSIX threads interface, similar to what Solaris 2.6 up
to 9 does. FreeBSD >= 700014 even provides a pthread_cancel stub in libc,
which means the alternate __gthread_active_p below cannot be used there. */
#if defined(__FreeBSD__) || (defined(__sun) && defined(__svr4__))
static volatile int __gthread_active = -1;
static void
__gthread_trigger (void)
{
__gthread_active = 1;
}
static inline int
__gthread_active_p (void)
{
static pthread_mutex_t __gthread_active_mutex = PTHREAD_MUTEX_INITIALIZER;
static pthread_once_t __gthread_active_once = PTHREAD_ONCE_INIT;
/* Avoid reading __gthread_active twice on the main code path. */
int __gthread_active_latest_value = __gthread_active;
/* This test is not protected to avoid taking a lock on the main code
path so every update of __gthread_active in a threaded program must
be atomic with regard to the result of the test. */
if (__builtin_expect (__gthread_active_latest_value < 0, 0))
{
if (__gthrw_(pthread_once))
{
/* If this really is a threaded program, then we must ensure that
__gthread_active has been set to 1 before exiting this block. */
__gthrw_(pthread_mutex_lock) (&__gthread_active_mutex);
__gthrw_(pthread_once) (&__gthread_active_once, __gthread_trigger);
__gthrw_(pthread_mutex_unlock) (&__gthread_active_mutex);
}
/* Make sure we'll never enter this block again. */
if (__gthread_active < 0)
__gthread_active = 0;
__gthread_active_latest_value = __gthread_active;
}
return __gthread_active_latest_value != 0;
}
#else /* neither FreeBSD nor Solaris */
static inline int
__gthread_active_p (void)
{
static void *const __gthread_active_ptr
= __extension__ (void *) &__gthrw_(pthread_cancel);
return __gthread_active_ptr != 0;
}
#endif /* FreeBSD or Solaris */
#else /* not SUPPORTS_WEAK */
/* Similar to Solaris, HP-UX 11 for PA-RISC provides stubs for pthread
calls in shared flavors of the HP-UX C library. Most of the stubs
have no functionality. The details are described in the "libc cumulative
patch" for each subversion of HP-UX 11. There are two special interfaces
provided for checking whether an application is linked to a pthread
library or not. However, these interfaces aren't available in early
libc versions. We also can't use pthread_once as some libc versions
call the init function. So, we use pthread_create to check whether it
is possible to create a thread or not. The stub implementation returns
the error number ENOSYS. */
#if defined(__hppa__) && defined(__hpux__)
#include <errno.h>
static volatile int __gthread_active = -1;
static void *
__gthread_start (void *arg __attribute__((unused)))
{
return NULL;
}
static void __gthread_active_init (void) __attribute__((noinline));
static void
__gthread_active_init (void)
{
static pthread_mutex_t __gthread_active_mutex = PTHREAD_MUTEX_INITIALIZER;
pthread_t t;
pthread_attr_t a;
int result;
__gthrw_(pthread_mutex_lock) (&__gthread_active_mutex);
if (__gthread_active < 0)
{
__gthrw_(pthread_attr_init) (&a);
__gthrw_(pthread_attr_setdetachstate) (&a, PTHREAD_CREATE_DETACHED);
result = __gthrw_(pthread_create) (&t, &a, __gthread_start, NULL);
if (result != ENOSYS)
__gthread_active = 1;
else
__gthread_active = 0;
__gthrw_(pthread_attr_destroy) (&a);
}
__gthrw_(pthread_mutex_unlock) (&__gthread_active_mutex);
}
static inline int
__gthread_active_p (void)
{
/* Avoid reading __gthread_active twice on the main code path. */
int __gthread_active_latest_value = __gthread_active;
/* This test is not protected to avoid taking a lock on the main code
path so every update of __gthread_active in a threaded program must
be atomic with regard to the result of the test. */
if (__builtin_expect (__gthread_active_latest_value < 0, 0))
{
__gthread_active_init ();
__gthread_active_latest_value = __gthread_active;
}
return __gthread_active_latest_value != 0;
}
#else /* not hppa-hpux */
static inline int
__gthread_active_p (void)
{
return 1;
}
#endif /* hppa-hpux */
#endif /* SUPPORTS_WEAK */
#ifdef _LIBOBJC
/* This is the config.h file in libobjc/ */
#include <config.h>
#ifdef HAVE_SCHED_H
# include <sched.h>
#endif
/* Key structure for maintaining thread specific storage */
static pthread_key_t _objc_thread_storage;
static pthread_attr_t _objc_thread_attribs;
/* Thread local storage for a single thread */
static void *thread_local_storage = NULL;
/* Backend initialization functions */
/* Initialize the threads subsystem. */
static inline int
__gthread_objc_init_thread_system (void)
{
if (__gthread_active_p ())
{
/* Initialize the thread storage key. */
if (__gthrw_(pthread_key_create) (&_objc_thread_storage, NULL) == 0)
{
/* The normal default detach state for threads is
* PTHREAD_CREATE_JOINABLE which causes threads to not die
* when you think they should. */
if (__gthrw_(pthread_attr_init) (&_objc_thread_attribs) == 0
&& __gthrw_(pthread_attr_setdetachstate) (&_objc_thread_attribs,
PTHREAD_CREATE_DETACHED) == 0)
return 0;
}
}
return -1;
}
/* Close the threads subsystem. */
static inline int
__gthread_objc_close_thread_system (void)
{
if (__gthread_active_p ()
&& __gthrw_(pthread_key_delete) (_objc_thread_storage) == 0
&& __gthrw_(pthread_attr_destroy) (&_objc_thread_attribs) == 0)
return 0;
return -1;
}
/* Backend thread functions */
/* Create a new thread of execution. */
static inline objc_thread_t
__gthread_objc_thread_detach (void (*func)(void *), void *arg)
{
objc_thread_t thread_id;
pthread_t new_thread_handle;
if (!__gthread_active_p ())
return NULL;
if (!(__gthrw_(pthread_create) (&new_thread_handle, NULL, (void *) func, arg)))
thread_id = (objc_thread_t) new_thread_handle;
else
thread_id = NULL;
return thread_id;
}
/* Set the current thread's priority. */
static inline int
__gthread_objc_thread_set_priority (int priority)
{
if (!__gthread_active_p ())
return -1;
else
{
#ifdef _POSIX_PRIORITY_SCHEDULING
#ifdef _POSIX_THREAD_PRIORITY_SCHEDULING
pthread_t thread_id = __gthrw_(pthread_self) ();
int policy;
struct sched_param params;
int priority_min, priority_max;
if (__gthrw_(pthread_getschedparam) (thread_id, &policy, &params) == 0)
{
if ((priority_max = __gthrw_(sched_get_priority_max) (policy)) == -1)
return -1;
if ((priority_min = __gthrw_(sched_get_priority_min) (policy)) == -1)
return -1;
if (priority > priority_max)
priority = priority_max;
else if (priority < priority_min)
priority = priority_min;
params.sched_priority = priority;
/*
* The solaris 7 and several other man pages incorrectly state that
* this should be a pointer to policy but pthread.h is universally
* at odds with this.
*/
if (__gthrw_(pthread_setschedparam) (thread_id, policy, &params) == 0)
return 0;
}
#endif /* _POSIX_THREAD_PRIORITY_SCHEDULING */
#endif /* _POSIX_PRIORITY_SCHEDULING */
return -1;
}
}
/* Return the current thread's priority. */
static inline int
__gthread_objc_thread_get_priority (void)
{
#ifdef _POSIX_PRIORITY_SCHEDULING
#ifdef _POSIX_THREAD_PRIORITY_SCHEDULING
if (__gthread_active_p ())
{
int policy;
struct sched_param params;
if (__gthrw_(pthread_getschedparam) (__gthrw_(pthread_self) (), &policy, &params) == 0)
return params.sched_priority;
else
return -1;
}
else
#endif /* _POSIX_THREAD_PRIORITY_SCHEDULING */
#endif /* _POSIX_PRIORITY_SCHEDULING */
return OBJC_THREAD_INTERACTIVE_PRIORITY;
}
/* Yield our process time to another thread. */
static inline void
__gthread_objc_thread_yield (void)
{
if (__gthread_active_p ())
__gthrw_(sched_yield) ();
}
/* Terminate the current thread. */
static inline int
__gthread_objc_thread_exit (void)
{
if (__gthread_active_p ())
/* exit the thread */
__gthrw_(pthread_exit) (&__objc_thread_exit_status);
/* Failed if we reached here */
return -1;
}
/* Returns an integer value which uniquely describes a thread. */
static inline objc_thread_t
__gthread_objc_thread_id (void)
{
if (__gthread_active_p ())
return (objc_thread_t) __gthrw_(pthread_self) ();
else
return (objc_thread_t) 1;
}
/* Sets the thread's local storage pointer. */
static inline int
__gthread_objc_thread_set_data (void *value)
{
if (__gthread_active_p ())
return __gthrw_(pthread_setspecific) (_objc_thread_storage, value);
else
{
thread_local_storage = value;
return 0;
}
}
/* Returns the thread's local storage pointer. */
static inline void *
__gthread_objc_thread_get_data (void)
{
if (__gthread_active_p ())
return __gthrw_(pthread_getspecific) (_objc_thread_storage);
else
return thread_local_storage;
}
/* Backend mutex functions */
/* Allocate a mutex. */
static inline int
__gthread_objc_mutex_allocate (objc_mutex_t mutex)
{
if (__gthread_active_p ())
{
mutex->backend = objc_malloc (sizeof (pthread_mutex_t));
if (__gthrw_(pthread_mutex_init) ((pthread_mutex_t *) mutex->backend, NULL))
{
objc_free (mutex->backend);
mutex->backend = NULL;
return -1;
}
}
return 0;
}
/* Deallocate a mutex. */
static inline int
__gthread_objc_mutex_deallocate (objc_mutex_t mutex)
{
if (__gthread_active_p ())
{
int count;
/*
* Posix Threads specifically require that the thread be unlocked
* for __gthrw_(pthread_mutex_destroy) to work.
*/
do
{
count = __gthrw_(pthread_mutex_unlock) ((pthread_mutex_t *) mutex->backend);
if (count < 0)
return -1;
}
while (count);
if (__gthrw_(pthread_mutex_destroy) ((pthread_mutex_t *) mutex->backend))
return -1;
objc_free (mutex->backend);
mutex->backend = NULL;
}
return 0;
}
/* Grab a lock on a mutex. */
static inline int
__gthread_objc_mutex_lock (objc_mutex_t mutex)
{
if (__gthread_active_p ()
&& __gthrw_(pthread_mutex_lock) ((pthread_mutex_t *) mutex->backend) != 0)
{
return -1;
}
return 0;
}
/* Try to grab a lock on a mutex. */
static inline int
__gthread_objc_mutex_trylock (objc_mutex_t mutex)
{
if (__gthread_active_p ()
&& __gthrw_(pthread_mutex_trylock) ((pthread_mutex_t *) mutex->backend) != 0)
{
return -1;
}
return 0;
}
/* Unlock the mutex */
static inline int
__gthread_objc_mutex_unlock (objc_mutex_t mutex)
{
if (__gthread_active_p ()
&& __gthrw_(pthread_mutex_unlock) ((pthread_mutex_t *) mutex->backend) != 0)
{
return -1;
}
return 0;
}
/* Backend condition mutex functions */
/* Allocate a condition. */
static inline int
__gthread_objc_condition_allocate (objc_condition_t condition)
{
if (__gthread_active_p ())
{
condition->backend = objc_malloc (sizeof (pthread_cond_t));
if (__gthrw_(pthread_cond_init) ((pthread_cond_t *) condition->backend, NULL))
{
objc_free (condition->backend);
condition->backend = NULL;
return -1;
}
}
return 0;
}
/* Deallocate a condition. */
static inline int
__gthread_objc_condition_deallocate (objc_condition_t condition)
{
if (__gthread_active_p ())
{
if (__gthrw_(pthread_cond_destroy) ((pthread_cond_t *) condition->backend))
return -1;
objc_free (condition->backend);
condition->backend = NULL;
}
return 0;
}
/* Wait on the condition */
static inline int
__gthread_objc_condition_wait (objc_condition_t condition, objc_mutex_t mutex)
{
if (__gthread_active_p ())
return __gthrw_(pthread_cond_wait) ((pthread_cond_t *) condition->backend,
(pthread_mutex_t *) mutex->backend);
else
return 0;
}
/* Wake up all threads waiting on this condition. */
static inline int
__gthread_objc_condition_broadcast (objc_condition_t condition)
{
if (__gthread_active_p ())
return __gthrw_(pthread_cond_broadcast) ((pthread_cond_t *) condition->backend);
else
return 0;
}
/* Wake up one thread waiting on this condition. */
static inline int
__gthread_objc_condition_signal (objc_condition_t condition)
{
if (__gthread_active_p ())
return __gthrw_(pthread_cond_signal) ((pthread_cond_t *) condition->backend);
else
return 0;
}
#else /* _LIBOBJC */
static inline int
__gthread_once (__gthread_once_t *__once, void (*__func) (void))
{
if (__gthread_active_p ())
return __gthrw_(pthread_once) (__once, __func);
else
return -1;
}
static inline int
__gthread_key_create (__gthread_key_t *__key, void (*__dtor) (void *))
{
return __gthrw_(pthread_key_create) (__key, __dtor);
}
static inline int
__gthread_key_delete (__gthread_key_t __key)
{
return __gthrw_(pthread_key_delete) (__key);
}
static inline void *
__gthread_getspecific (__gthread_key_t __key)
{
return __gthrw_(pthread_getspecific) (__key);
}
static inline int
__gthread_setspecific (__gthread_key_t __key, const void *__ptr)
{
return __gthrw_(pthread_setspecific) (__key, __ptr);
}
static inline int
__gthread_mutex_destroy (__gthread_mutex_t *__mutex)
{
if (__gthread_active_p ())
return __gthrw_(pthread_mutex_destroy) (__mutex);
else
return 0;
}
static inline int
__gthread_mutex_lock (__gthread_mutex_t *__mutex)
{
if (__gthread_active_p ())
return __gthrw_(pthread_mutex_lock) (__mutex);
else
return 0;
}
static inline int
__gthread_mutex_trylock (__gthread_mutex_t *__mutex)
{
if (__gthread_active_p ())
return __gthrw_(pthread_mutex_trylock) (__mutex);
else
return 0;
}
static inline int
__gthread_mutex_unlock (__gthread_mutex_t *__mutex)
{
if (__gthread_active_p ())
return __gthrw_(pthread_mutex_unlock) (__mutex);
else
return 0;
}
static inline int
__gthread_recursive_mutex_init_function (__gthread_recursive_mutex_t *__mutex)
{
__mutex->depth = 0;
__mutex->owner = (pthread_t) 0;
return __gthrw_(pthread_mutex_init) (&__mutex->actual, NULL);
}
static inline int
__gthread_recursive_mutex_lock (__gthread_recursive_mutex_t *__mutex)
{
if (__gthread_active_p ())
{
pthread_t __me = __gthrw_(pthread_self) ();
if (__mutex->owner != __me)
{
__gthrw_(pthread_mutex_lock) (&__mutex->actual);
__mutex->owner = __me;
}
__mutex->depth++;
}
return 0;
}
static inline int
__gthread_recursive_mutex_trylock (__gthread_recursive_mutex_t *__mutex)
{
if (__gthread_active_p ())
{
pthread_t __me = __gthrw_(pthread_self) ();
if (__mutex->owner != __me)
{
if (__gthrw_(pthread_mutex_trylock) (&__mutex->actual))
return 1;
__mutex->owner = __me;
}
__mutex->depth++;
}
return 0;
}
static inline int
__gthread_recursive_mutex_unlock (__gthread_recursive_mutex_t *__mutex)
{
if (__gthread_active_p ())
{
if (--__mutex->depth == 0)
{
__mutex->owner = (pthread_t) 0;
__gthrw_(pthread_mutex_unlock) (&__mutex->actual);
}
}
return 0;
}
static inline int
__gthread_cond_broadcast (__gthread_cond_t *__cond)
{
return __gthrw_(pthread_cond_broadcast) (__cond);
}
static inline int
__gthread_cond_wait (__gthread_cond_t *__cond, __gthread_mutex_t *__mutex)
{
return __gthrw_(pthread_cond_wait) (__cond, __mutex);
}
static inline int
__gthread_cond_wait_recursive (__gthread_cond_t *__cond,
__gthread_recursive_mutex_t *__mutex)
{
return __gthrw_(pthread_cond_wait) (__cond, &__mutex->actual);
}
#endif /* _LIBOBJC */
#endif /* ! GCC_GTHR_POSIX_H */
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