/*
 * cleanup.c
 *
 * Description:
 * This translation unit implements routines associated
 * with cleaning up threads.
 *
 *
 * --------------------------------------------------------------------------
 *
 *      Pthreads4w - POSIX Threads Library for Win32
 *      Copyright(C) 1998 John E. Bossom
 *      Copyright(C) 1999-2018, Pthreads4w contributors
 *
 *      Homepage: https://sourceforge.net/projects/pthreads4w/
 *
 *      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:
 *      https://sourceforge.net/p/pthreads4w/wiki/Contributors/
 *
 * This file is part of Pthreads4w.
 *
 *    Pthreads4w 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 of the License, or
 *    (at your option) any later version.
 *
 *    Pthreads4w 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 Pthreads4w.  If not, see <http://www.gnu.org/licenses/>. *
 */

#ifdef HAVE_CONFIG_H
# include <config.h>
#endif

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


/*
 * The functions ptw32_pop_cleanup and ptw32_push_cleanup
 * are implemented here for applications written in C with no
 * SEH or C++ destructor support. 
 */

ptw32_cleanup_t *
ptw32_pop_cleanup (int execute)
     /*
      * ------------------------------------------------------
      * DOCPUBLIC
      *      This function pops the most recently pushed cleanup
      *      handler. If execute is nonzero, then the cleanup handler
      *      is executed if non-null.
      *
      * PARAMETERS
      *      execute
      *              if nonzero, execute the cleanup handler
      *
      *
      * DESCRIPTION
      *      This function pops the most recently pushed cleanup
      *      handler. If execute is nonzero, then the cleanup handler
      *      is executed if non-null.
      *      NOTE: specify 'execute' as nonzero to avoid duplication
      *                of common cleanup code.
      *
      * RESULTS
      *              N/A
      *
      * ------------------------------------------------------
      */
{
  ptw32_cleanup_t *cleanup;

  cleanup = (ptw32_cleanup_t *) pthread_getspecific (ptw32_cleanupKey);

  if (cleanup != NULL)
    {
      if (execute && (cleanup->routine != NULL))
	{

	  (*cleanup->routine) (cleanup->arg);

	}

      pthread_setspecific (ptw32_cleanupKey, (void *) cleanup->prev);

    }

  return (cleanup);

}				/* ptw32_pop_cleanup */


void
ptw32_push_cleanup (ptw32_cleanup_t * cleanup,
		    ptw32_cleanup_callback_t routine, void *arg)
     /*
      * ------------------------------------------------------
      * DOCPUBLIC
      *      This function pushes a new cleanup handler onto the thread's stack
      *      of cleanup handlers. Each cleanup handler pushed onto the stack is
      *      popped and invoked with the argument 'arg' when
      *              a) the thread exits by calling 'pthread_exit',
      *              b) when the thread acts on a cancellation request,
      *              c) or when the thread calls pthread_cleanup_pop with a nonzero
      *                 'execute' argument
      *
      * PARAMETERS
      *      cleanup
      *              a pointer to an instance of pthread_cleanup_t,
      *
      *      routine
      *              pointer to a cleanup handler,
      *
      *      arg
      *              parameter to be passed to the cleanup handler
      *
      *
      * DESCRIPTION
      *      This function pushes a new cleanup handler onto the thread's stack
      *      of cleanup handlers. Each cleanup handler pushed onto the stack is
      *      popped and invoked with the argument 'arg' when
      *              a) the thread exits by calling 'pthread_exit',
      *              b) when the thread acts on a cancellation request,
      *              c) or when the thrad calls pthread_cleanup_pop with a nonzero
      *                 'execute' argument
      *      NOTE: pthread_push_cleanup, ptw32_pop_cleanup must be paired
      *                in the same lexical scope.
      *
      * RESULTS
      *              pthread_cleanup_t *
      *                              pointer to the previous cleanup
      *
      * ------------------------------------------------------
      */
{
  cleanup->routine = routine;
  cleanup->arg = arg;

  cleanup->prev = (ptw32_cleanup_t *) pthread_getspecific (ptw32_cleanupKey);

  pthread_setspecific (ptw32_cleanupKey, (void *) cleanup);

}				/* ptw32_push_cleanup */