/*
 * pthread_detach.c
 *
 * Description:
 * This translation unit implements functions related to thread
 * synchronisation.
 *
 * --------------------------------------------------------------------------
 *
 *      Pthreads-win32 - POSIX Threads Library for Win32
 *      Copyright(C) 1998 John E. Bossom
 *      Copyright(C) 1999,2005 Pthreads-win32 contributors
 * 
 *      Contact Email: rpj@callisto.canberra.edu.au
 * 
 *      The current list of contributors is contained
 *      in the file CONTRIBUTORS included with the source
 *      code distribution. The list can also be seen at the
 *      following World Wide Web location:
 *      http://sources.redhat.com/pthreads-win32/contributors.html
 * 
 *      This library is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU Lesser General Public
 *      License as published by the Free Software Foundation; either
 *      version 2 of the License, or (at your option) any later version.
 * 
 *      This library 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
 *      Lesser General Public License for more details.
 * 
 *      You should have received a copy of the GNU Lesser General Public
 *      License along with this library in the file COPYING.LIB;
 *      if not, write to the Free Software Foundation, Inc.,
 *      59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
 */

#include "pthread.h"
#include "implement.h"

/*
 * Not needed yet, but defining it should indicate clashes with build target
 * environment that should be fixed.
 */
#include <signal.h>


int
pthread_detach (pthread_t thread)
     /*
      * ------------------------------------------------------
      * DOCPUBLIC
      *      This function detaches the given thread.
      *
      * PARAMETERS
      *      thread
      *              an instance of a pthread_t
      *
      *
      * DESCRIPTION
      *      This function detaches the given thread. You may use it to
      *      detach the main thread or to detach a joinable thread.
      *      NOTE:   detached threads cannot be joined;
      *              storage is freed immediately on termination.
      *
      * RESULTS
      *              0               successfully detached the thread,
      *              EINVAL          thread is not a joinable thread,
      *              ENOSPC          a required resource has been exhausted,
      *              ESRCH           no thread could be found for 'thread',
      *
      * ------------------------------------------------------
      */
{
  int result;
  BOOL destroyIt = PTW32_FALSE;
  ptw32_thread_t * tp = (ptw32_thread_t *) thread.p;

  EnterCriticalSection (&ptw32_thread_reuse_lock);

  if (NULL == tp
      || thread.x != tp->ptHandle.x)
    {
      result = ESRCH;
    }
  else if (PTHREAD_CREATE_DETACHED == tp->detachState)
    {
      result = EINVAL;
    }
  else
    {
      /*
       * Joinable ptw32_thread_t structs are not scavenged until
       * a join or detach is done. The thread may have exited already,
       * but all of the state and locks etc are still there.
       */
      result = 0;

      if (pthread_mutex_lock (&tp->cancelLock) == 0)
	{
	  if (tp->state != PThreadStateLast)
	    {
	      tp->detachState = PTHREAD_CREATE_DETACHED;
	    }
	  else if (tp->detachState != PTHREAD_CREATE_DETACHED)
	    {
	      /*
	       * Thread is joinable and has exited or is exiting.
	       */
	      destroyIt = PTW32_TRUE;
	    }
	  (void) pthread_mutex_unlock (&tp->cancelLock);
	}
      else
	{
	  /* cancelLock shouldn't fail, but if it does ... */
	  result = ESRCH;
	}
    }

  LeaveCriticalSection (&ptw32_thread_reuse_lock);

  if (result == 0)
    {
      /* Thread is joinable */

      if (destroyIt)
	{
	  /* The thread has exited or is exiting but has not been joined or
	   * detached. Need to wait in case it's still exiting.
	   */
	  (void) WaitForSingleObject(tp->threadH, INFINITE);
	  ptw32_threadDestroy (thread);
	}
    }

  return (result);

}				/* pthread_detach */
