gcc/gcc/gthr-dce.h

/* Threads compatibility routines for libgcc2 and libobjc.  */
/* Compile this one with gcc.  */
/* Copyright (C) 1997, 1999, 2000, 2001, 2004, 2005
   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 2, 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.

You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING.  If not, write to the Free
Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301, USA.  */

/* As a special exception, if you link this library with other files,
   some of which are compiled with GCC, to produce an executable,
   this library does not by itself cause the resulting executable
   to be covered by the GNU General Public License.
   This exception does not however invalidate any other reasons why
   the executable file might be covered by the GNU General Public License.  */

#ifndef GCC_GTHR_DCE_H
#define GCC_GTHR_DCE_H

/* If _DCE_THREADS is not defined, then we're building the single
   threaded version of the libraries and do not want to reference
   anything related to pthreads or dce.  */
#ifndef _DCE_THREADS
#include "gthr-single.h"
#else
/* DCE threads interface.
   DCE threads are based on POSIX threads draft 4, and many things
   have changed since then.  */

#define __GTHREADS 1

#include <pthread.h>

typedef pthread_key_t __gthread_key_t;
typedef pthread_once_t __gthread_once_t;
typedef pthread_mutex_t __gthread_mutex_t;
typedef pthread_mutex_t __gthread_recursive_mutex_t;

#define __GTHREAD_ONCE_INIT pthread_once_init

#define __GTHREAD_MUTEX_INIT_FUNCTION __gthread_mutex_init_function
#define __GTHREAD_RECURSIVE_MUTEX_INIT_FUNCTION __gthread_recursive_mutex_init_function

#define __GTHREAD_MUTEX_INIT_DEFAULT pthread_once_init

#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_keycreate)
__gthrw(pthread_getspecific)
__gthrw(pthread_setspecific)
__gthrw(pthread_create)
__gthrw(pthread_mutex_init)
__gthrw(pthread_mutex_lock)
__gthrw(pthread_mutex_trylock)
__gthrw(pthread_mutex_unlock)
__gthrw(pthread_mutexattr_create)
__gthrw(pthread_mutexattr_setkind_np)
__gthrw(pthread_mutexattr_delete)

#ifdef _LIBOBJC
/* Objective-C.  */
__gthrw(pthread_cond_broadcast)
__gthrw(pthread_cond_destroy)
__gthrw(pthread_cond_init)
__gthrw(pthread_cond_signal)
__gthrw(pthread_cond_wait)
__gthrw(pthread_exit)

#ifdef pthread_getunique_np
# define __gthrw_pthread_getunique_np pthread_getunique_np
#else
__gthrw(pthread_getunique_np)
# define __gthrw_pthread_getunique_np __gthrw_(pthread_getunique_np)
#endif

__gthrw(pthread_mutex_destroy)
__gthrw(pthread_self)
__gthrw(pthread_yield)
#endif

#if SUPPORTS_WEAK && GTHREAD_USE_WEAK

static inline int
__gthread_active_p (void)
{
  static void *const __gthread_active_ptr = (void *) &__gthrw_(pthread_create);
  return __gthread_active_ptr != 0;
}

#else /* not SUPPORTS_WEAK */

static inline int
__gthread_active_p (void)
{
  return 1;
}

#endif /* SUPPORTS_WEAK */

#ifdef _LIBOBJC

/* Key structure for maintaining thread specific storage */
static pthread_key_t _objc_thread_storage;

/* 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.  */
    return __gthrw_(pthread_keycreate) (&_objc_thread_storage, NULL);
  else
    return -1;
}

/* Close the threads subsystem.  */
static inline int
__gthread_objc_close_thread_system (void)
{
  if (__gthread_active_p ())
    return 0;
  else
    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, pthread_attr_default,
			(void *) func, arg)))
    {
      /* ??? May not work! (64bit) */
      thread_id = *(objc_thread_t *) &new_thread_handle;
      pthread_detach (&new_thread_handle); /* Fully detach thread.  */
    }
  else
    thread_id = NULL;

  return thread_id;
}

/* Set the current thread's priority.  */
static inline int
__gthread_objc_thread_set_priority (int priority)
{
  int sys_priority = 0;

  if (!__gthread_active_p ())
    return -1;

  switch (priority)
    {
    case OBJC_THREAD_INTERACTIVE_PRIORITY:
      sys_priority = (PRI_FG_MIN_NP + PRI_FG_MAX_NP) / 2;
      break;
    default:
    case OBJC_THREAD_BACKGROUND_PRIORITY:
      sys_priority = (PRI_BG_MIN_NP + PRI_BG_MAX_NP) / 2;
      break;
    case OBJC_THREAD_LOW_PRIORITY:
      sys_priority = (PRI_BG_MIN_NP + PRI_BG_MAX_NP) / 2;
      break;
    }

  /* Change the priority.  */
  if (pthread_setprio (__gthrw_(pthread_self) (), sys_priority) >= 0)
    return 0;
  else
    /* Failed */
    return -1;
}

/* Return the current thread's priority.  */
static inline int
__gthread_objc_thread_get_priority (void)
{
  int sys_priority;

  if (__gthread_active_p ())
    {
      if ((sys_priority = pthread_getprio (__gthrw_(pthread_self) ())) >= 0)
	{
	  if (sys_priority >= PRI_FG_MIN_NP
	      && sys_priority <= PRI_FG_MAX_NP)
	    return OBJC_THREAD_INTERACTIVE_PRIORITY;
	  if (sys_priority >= PRI_BG_MIN_NP
	      && sys_priority <= PRI_BG_MAX_NP)
	    return OBJC_THREAD_BACKGROUND_PRIORITY;
	  return OBJC_THREAD_LOW_PRIORITY;
	}

      /* Failed */
      return -1;
    }
  else
    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_(pthread_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 ())
    {
      pthread_t self = __gthrw_(pthread_self) ();

      return (objc_thread_t) __gthrw_pthread_getunique_np (&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)
{
  void *value = NULL;

  if (__gthread_active_p ())
    {
      if (!(__gthrw_(pthread_getspecific) (_objc_thread_storage, &value)))
	return value;

      return NULL;
    }
  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,
			      pthread_mutexattr_default))
	{
	  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 ())
    {
      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 ())
    return __gthrw_(pthread_mutex_lock) ((pthread_mutex_t *) mutex->backend);
  else
    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) != 1)
    return -1;

  return 0;
}

/* Unlock the mutex */
static inline int
__gthread_objc_mutex_unlock (objc_mutex_t mutex)
{
  if (__gthread_active_p ())
    return __gthrw_(pthread_mutex_unlock) ((pthread_mutex_t *) mutex->backend);
  else
    return 0;
}

/* Backend condition mutex functions */

/* Allocate a condition.  */
static inline int
__gthread_objc_condition_allocate (objc_condition_t condition
				   __attribute__ ((__unused__)))
{
  if (__gthread_active_p ())
    /* Unimplemented.  */
    return -1;
  else
    return 0;
}

/* Deallocate a condition.  */
static inline int
__gthread_objc_condition_deallocate (objc_condition_t condition
				     __attribute__ ((__unused__)))
{
  if (__gthread_active_p ())
    /* Unimplemented.  */
    return -1;
  else
    return 0;
}

/* Wait on the condition */
static inline int
__gthread_objc_condition_wait (objc_condition_t condition
			       __attribute__ ((__unused__)),
			       objc_mutex_t mutex __attribute__ ((__unused__)))
{
  if (__gthread_active_p ())
    /* Unimplemented.  */
    return -1;
  else
    return 0;
}

/* Wake up all threads waiting on this condition.  */
static inline int
__gthread_objc_condition_broadcast (objc_condition_t condition
				    __attribute__ ((__unused__)))
{
  if (__gthread_active_p ())
    /* Unimplemented.  */
    return -1;
  else
    return 0;
}

/* Wake up one thread waiting on this condition.  */
static inline int
__gthread_objc_condition_signal (objc_condition_t condition
				 __attribute__ ((__unused__)))
{
  if (__gthread_active_p ())
    /* Unimplemented.  */
    return -1;
  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_keycreate) (key, dtor);
}

static inline int
__gthread_key_delete (__gthread_key_t key __attribute__ ((__unused__)))
{
  /* Operation is not supported.  */
  return -1;
}

static inline void *
__gthread_getspecific (__gthread_key_t key)
{
  void *ptr;
  if (__gthrw_(pthread_getspecific) (key, &ptr) == 0)
    return ptr;
  else
    return 0;
}

static inline int
__gthread_setspecific (__gthread_key_t key, const void *ptr)
{
  return __gthrw_(pthread_setspecific) (key, (void *) ptr);
}

static inline void
__gthread_mutex_init_function (__gthread_mutex_t *mutex)
{
  if (__gthread_active_p ())
    __gthrw_(pthread_mutex_init) (mutex, pthread_mutexattr_default);
}

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)
{
  if (__gthread_active_p ())
    {
      pthread_mutexattr_t attr;
      int r;

      r = __gthrw_(pthread_mutexattr_create) (&attr);
      if (!r)
	r = __gthrw_(pthread_mutexattr_setkind_np) (&attr, MUTEX_RECURSIVE_NP);
      if (!r)
	r = __gthrw_(pthread_mutex_init) (mutex, attr);
      if (!r)
	r = __gthrw_(pthread_mutexattr_delete) (&attr);
      return r;
    }
  return 0;
}

static inline int
__gthread_recursive_mutex_lock (__gthread_recursive_mutex_t *mutex)
{
  return __gthread_mutex_lock (mutex);
}

static inline int
__gthread_recursive_mutex_trylock (__gthread_recursive_mutex_t *mutex)
{
  return __gthread_mutex_trylock (mutex);
}

static inline int
__gthread_recursive_mutex_unlock (__gthread_recursive_mutex_t *mutex)
{
  return __gthread_mutex_unlock (mutex);
}

#endif /* _LIBOBJC */

#endif
#endif /* ! GCC_GTHR_DCE_H */