/* GNU Objective C Runtime Thread Interface - OS/2 emx Implementation
   Copyright (C) 1996, 1997, 2009 Free Software Foundation, Inc.
   Contributed by Thomas Baier (baier@ci.tuwien.ac.at)

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/>.  */


#include "objc/thr.h"
#include "objc/runtime.h"

#define INCL_DOSSEMAPHORES
#define INCL_DOSPROCESS

/*
 * conflicts with objc.h:       SEL, BOOL, id
 * solution:  prefixing those with _OS2_ before including <os2.h>
 */
#define SEL _OS2_SEL
#define BOOL _OS2_BOOL
#define id _OS2_id
#include <os2.h>
#undef id
#undef SEL
#undef BOOL

#include <stdlib.h>

/* Backend initialization functions */

/* Initialize the threads subsystem. */
int
__objc_init_thread_system(void)
{
  return 0;
}

/* Close the threads subsystem. */
int
__objc_close_thread_system(void)
{
  return 0;
}

/* Backend thread functions */

/* Create a new thread of execution. */
objc_thread_t
__objc_thread_detach(void (*func)(void *arg), void *arg)
{
  int thread_id = 0;

  if ((thread_id = _beginthread (func,NULL,32768,arg)) < 0)
    thread_id = 0;
  
  return (objc_thread_t)thread_id;
}

/* Set the current thread's priority. */
int
__objc_thread_set_priority(int priority)
{
  ULONG sys_class = 0;
  ULONG sys_priority = 0;

  /* OBJC_THREAD_INTERACTIVE_PRIORITY -> PRTYC_FOREGROUNDSERVER
   * OBJC_THREAD_BACKGROUND_PRIORITY  -> PRTYC_REGULAR
   * OBJC_THREAD_LOW_PRIORITY         -> PRTYC_IDLETIME */
  
  switch (priority) {
  case OBJC_THREAD_INTERACTIVE_PRIORITY:
    sys_class = PRTYC_REGULAR;
    sys_priority = 10;
    break;
  default:
  case OBJC_THREAD_BACKGROUND_PRIORITY:
    sys_class = PRTYC_IDLETIME;
    sys_priority = 25;
    break;
  case OBJC_THREAD_LOW_PRIORITY:
    sys_class = PRTYC_IDLETIME;
    sys_priority = 0;
    break;
  }

  /* Change priority */
  if (!DosSetPriority (PRTYS_THREAD,sys_class,sys_priority,*_threadid))
    return 0;
  else
    return -1;
}

/* Return the current thread's priority. */
int
__objc_thread_get_priority(void)
{
  PTIB ptib;
  PPIB ppib;

  /* get information about current thread */
  DosGetInfoBlocks (&ptib,&ppib);

  switch (ptib->tib_ptib2->tib2_ulpri)
    {
    case PRTYC_IDLETIME:
    case PRTYC_REGULAR:
    case PRTYC_TIMECRITICAL:
    case PRTYC_FOREGROUNDSERVER:
    default:
      return OBJC_THREAD_INTERACTIVE_PRIORITY;
    }

  return -1;
}

/* Yield our process time to another thread. */
void
__objc_thread_yield(void)
{
  DosSleep (0);
}

/* Terminate the current thread. */
int
__objc_thread_exit(void)
{
  /* terminate the thread, NEVER use DosExit () */
  _endthread ();

  /* Failed if we reached here */
  return -1;
}

/* Returns an integer value which uniquely describes a thread. */
objc_thread_t
__objc_thread_id(void)
{
  return (objc_thread_t) *_threadid;
}

/* Sets the thread's local storage pointer. */
int
__objc_thread_set_data(void *value)
{
  *_threadstore () = value;

  return 0;
}

/* Returns the thread's local storage pointer. */
void *
__objc_thread_get_data(void)
{
  return *_threadstore ();
}

/* Backend mutex functions */

/* Allocate a mutex. */
int
__objc_mutex_allocate(objc_mutex_t mutex)
{
  if (DosCreateMutexSem (NULL, (HMTX)(&(mutex->backend)),0L,0) > 0)
    return -1;
  else
    return 0;
}

/* Deallocate a mutex. */
int
__objc_mutex_deallocate(objc_mutex_t mutex)
{
  DosCloseMutexSem ((HMTX)(mutex->backend));
  return 0;
}

/* Grab a lock on a mutex. */
int
__objc_mutex_lock(objc_mutex_t mutex)
{
  if (DosRequestMutexSem ((HMTX)(mutex->backend),-1L) != 0)
    return -1;
  else
    return 0;
}

/* Try to grab a lock on a mutex. */
int
__objc_mutex_trylock(objc_mutex_t mutex)
{
  if (DosRequestMutexSem ((HMTX)(mutex->backend),0L) != 0)
    return -1;
  else
    return 0;
}

/* Unlock the mutex */
int
__objc_mutex_unlock(objc_mutex_t mutex)
{
  if (DosReleaseMutexSem((HMTX)(mutex->backend)) != 0)
    return -1;
  else
    return 0;
}

/* Backend condition mutex functions */

/* Allocate a condition. */
int
__objc_condition_allocate(objc_condition_t condition)
{
  /* Unimplemented. */
  return -1;
}

/* Deallocate a condition. */
int
__objc_condition_deallocate(objc_condition_t condition)
{
  /* Unimplemented. */
  return -1;
}

/* Wait on the condition */
int
__objc_condition_wait(objc_condition_t condition, objc_mutex_t mutex)
{
  /* Unimplemented. */
  return -1;
}

/* Wake up all threads waiting on this condition. */
int
__objc_condition_broadcast(objc_condition_t condition)
{
  /* Unimplemented. */
  return -1;
}

/* Wake up one thread waiting on this condition. */
int
__objc_condition_signal(objc_condition_t condition)
{
  /* Unimplemented. */
  return -1;
}

/* End of File */