/* Threads compatibility routines for libgcc2 and libobjc.  */
/* Compile this one with gcc.  */
/* Copyright (C) 1997, 1999, 2000 Free Software Foundation, Inc.

This file is part of GNU CC.

GNU CC 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.

GNU CC 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 GNU CC; see the file COPYING.  If not, write to
the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, 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 __gthr_single_h
#define __gthr_single_h

/* Just provide compatibility for mutex handling. */

typedef int __gthread_mutex_t;

#define __GTHREAD_MUTEX_INIT 0

#ifdef __cplusplus
#define UNUSED(x)
#else
#define UNUSED(x) x __attribute__((unused))
#endif

#ifdef _LIBOBJC

/* 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)
{
  /* No thread support available */
  return -1;
}

/* Close the threads subsystem. */
static inline int
__gthread_objc_close_thread_system(void)
{
  /* No thread support available */
  return -1;
}

/* Backend thread functions */

/* Create a new thread of execution. */
static inline objc_thread_t
__gthread_objc_thread_detach(void (* func)(void *), void * UNUSED(arg))
{
  /* No thread support available */
  return NULL;
}

/* Set the current thread's priority. */
static inline int
__gthread_objc_thread_set_priority(int UNUSED(priority))
{
  /* No thread support available */
  return -1;
}

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

/* Yield our process time to another thread. */
static inline void
__gthread_objc_thread_yield(void)
{
  return;
}

/* Terminate the current thread. */
static inline int
__gthread_objc_thread_exit(void)
{
  /* No thread support available */
  /* Should we really exit the program */
  /* exit(&__objc_thread_exit_status); */
  return -1;
}

/* Returns an integer value which uniquely describes a thread. */
static inline objc_thread_t
__gthread_objc_thread_id(void)
{
  /* No thread support, use 1. */
  return (objc_thread_t)1;
}

/* Sets the thread's local storage pointer. */
static inline int
__gthread_objc_thread_set_data(void *value)
{
  thread_local_storage = value;
  return 0;
}

/* Returns the thread's local storage pointer. */
static inline void *
__gthread_objc_thread_get_data(void)
{
  return thread_local_storage;
}

/* Backend mutex functions */

/* Allocate a mutex. */
static inline int
__gthread_objc_mutex_allocate(objc_mutex_t UNUSED(mutex))
{
  return 0;
}

/* Deallocate a mutex. */
static inline int
__gthread_objc_mutex_deallocate(objc_mutex_t UNUSED(mutex))
{
  return 0;
}

/* Grab a lock on a mutex. */
static inline int
__gthread_objc_mutex_lock(objc_mutex_t UNUSED(mutex))
{
  /* There can only be one thread, so we always get the lock */
  return 0;
}

/* Try to grab a lock on a mutex. */
static inline int
__gthread_objc_mutex_trylock(objc_mutex_t UNUSED(mutex))
{
  /* There can only be one thread, so we always get the lock */
  return 0;
}

/* Unlock the mutex */
static inline int
__gthread_objc_mutex_unlock(objc_mutex_t UNUSED(mutex))
{
  return 0;
}

/* Backend condition mutex functions */

/* Allocate a condition. */
static inline int
__gthread_objc_condition_allocate(objc_condition_t UNUSED(condition))
{
  return 0;
}

/* Deallocate a condition. */
static inline int
__gthread_objc_condition_deallocate(objc_condition_t UNUSED(condition))
{
  return 0;
}

/* Wait on the condition */
static inline int
__gthread_objc_condition_wait(objc_condition_t UNUSED(condition),
			      objc_mutex_t UNUSED(mutex))
{
  return 0;
}

/* Wake up all threads waiting on this condition. */
static inline int
__gthread_objc_condition_broadcast(objc_condition_t UNUSED(condition))
{
  return 0;
}

/* Wake up one thread waiting on this condition. */
static inline int
__gthread_objc_condition_signal(objc_condition_t UNUSED(condition))
{
  return 0;
}

#else /* _LIBOBJC */

static inline int
__gthread_active_p (void)
{
  return 0;
}

static inline int
__gthread_mutex_lock (__gthread_mutex_t * UNUSED(mutex))
{
  return 0;
}

static inline int
__gthread_mutex_trylock (__gthread_mutex_t * UNUSED(mutex))
{
  return 0;
}

static inline int
__gthread_mutex_unlock (__gthread_mutex_t * UNUSED(mutex))
{
  return 0;
}

#endif /* _LIBOBJC */

#undef UNUSED

#endif /* not __gthr_single_h */
