Subversion Repositories openrisc_2011-10-31

/* 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;