/* Single-image implementation of GNU Fortran Coarray Library
   Copyright (C) 2011
   Free Software Foundation, Inc.
   Contributed by Tobias Burnus <burnus@net-b.de>

This file is part of the GNU Fortran Coarray Runtime Library (libcaf).

Libcaf 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.

Libcaf 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 "libcaf.h"
#include <stdio.h>  /* For fputs and fprintf.  */
#include <stdlib.h> /* For exit and malloc.  */
#include <string.h> /* For memcpy and memset.  */
#include <stdarg.h> /* For variadic arguments.  */

/* Define GFC_CAF_CHECK to enable run-time checking.  */
/* #define GFC_CAF_CHECK  1  */

/* Single-image implementation of the CAF library.
   Note: For performance reasons -fcoarry=single should be used
   rather than this library.  */

/* Global variables.  */
caf_static_t *caf_static_list = NULL;


/* Keep in sync with mpi.c.  */
static void
caf_runtime_error (const char *message, ...)
{
  va_list ap;
  fprintf (stderr, "Fortran runtime error: ");
  va_start (ap, message);
  vfprintf (stderr, message, ap);
  va_end (ap);
  fprintf (stderr, "\n");

  /* FIXME: Shutdown the Fortran RTL to flush the buffer.  PR 43849.  */
  exit (EXIT_FAILURE);
}

void
_gfortran_caf_init (int *argc __attribute__ ((unused)),
		    char ***argv __attribute__ ((unused)),
		    int *this_image, int *num_images)
{
  *this_image = 1;
  *num_images = 1;
}


void
_gfortran_caf_finalize (void)
{
  while (caf_static_list != NULL)
    {
      caf_static_t *tmp = caf_static_list->prev;
      free (caf_static_list->token[0]);
      free (caf_static_list->token);
      free (caf_static_list);
      caf_static_list = tmp;
    }
}


void *
_gfortran_caf_register (ptrdiff_t size, caf_register_t type, void **token,
			int *stat, char *errmsg, int errmsg_len)
{
  void *local;

  local = malloc (size);
  token = malloc (sizeof (void*) * 1);
  token[0] = local;

  if (unlikely (local == NULL || token == NULL))
    {
      const char msg[] = "Failed to allocate coarray";
      if (stat)
	{
	  *stat = 1;
	  if (errmsg_len > 0)
	    {
	      int len = ((int) sizeof (msg) > errmsg_len) ? errmsg_len
							  : (int) sizeof (msg);
	      memcpy (errmsg, msg, len);
	      if (errmsg_len > len)
		memset (&errmsg[len], ' ', errmsg_len-len);
	    }
	  return NULL;
	}
      else
	  caf_runtime_error (msg);
    }

  if (stat)
    *stat = 0;

  if (type == CAF_REGTYPE_COARRAY_STATIC)
    {
      caf_static_t *tmp = malloc (sizeof (caf_static_t));
      tmp->prev  = caf_static_list;
      tmp->token = token;
      caf_static_list = tmp;
    }
  return local;
}


void
_gfortran_caf_deregister (void **token, int *stat,
			  char *errmsg __attribute__ ((unused)),
			  int errmsg_len __attribute__ ((unused)))
{
  free (*token);
  free (token);

  if (stat)
    *stat = 0;
}


void
_gfortran_caf_sync_all (int *stat,
			char *errmsg __attribute__ ((unused)),
			int errmsg_len __attribute__ ((unused)))
{
  if (stat)
    *stat = 0;
}


void
_gfortran_caf_sync_images (int count __attribute__ ((unused)),
			   int images[] __attribute__ ((unused)),
			   int *stat,
			   char *errmsg __attribute__ ((unused)),
			   int errmsg_len __attribute__ ((unused)))
{
#ifdef GFC_CAF_CHECK
  int i;

  for (i = 0; i < count; i++)
    if (images[i] != 1)
      {
	fprintf (stderr, "COARRAY ERROR: Invalid image index %d to SYNC "
		 "IMAGES", images[i]);
	exit (EXIT_FAILURE);
      }
#endif

  if (stat)
    *stat = 0;
}


void
_gfortran_caf_error_stop_str (const char *string, int32_t len)
{
  fputs ("ERROR STOP ", stderr);
  while (len--)
    fputc (*(string++), stderr);
  fputs ("\n", stderr);

  exit (1);
}


void
_gfortran_caf_error_stop (int32_t error)
{
  fprintf (stderr, "ERROR STOP %d\n", error);
  exit (error);
}