/*! \file

Copyright 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002,
2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014,
2015, 2016, 2017, 2018
University Corporation for Atmospheric Research/Unidata.

See \ref copyright file for more info.

*/

/* This is a quickie tester for netcdf-4.

   This just excersizes MPI file I/O to make sure everything's working
   properly. If this doesn't work, netcdf/HDF5 parallel I/O also won't
   work.

   $Id: tst_mpi_parallel.c,v 1.2 2009/08/19 15:58:57 ed Exp $
*/

#include <nc_tests.h>
#include "err_macros.h"
#include <mpi.h>

#define FILE "tst_mpi_parallel.bin"

int
main(int argc, char **argv)
{
   /* MPI stuff. */
   MPI_File fh;
   int my_rank, mpi_size;
   int data_in;
   MPI_Status status;

   /* Initialize MPI. */
   MPI_Init(&argc,&argv);
   MPI_Comm_size(MPI_COMM_WORLD, &mpi_size);
   MPI_Comm_rank(MPI_COMM_WORLD, &my_rank);
   /*MPI_Get_processor_name(mpi_name, &mpi_namelen);*/
   /*printf("mpi_name: %s size: %d rank: %d\n", mpi_name,
     mpi_size, my_rank);*/

   if (my_rank == 0)
   {
      printf("\n*** Testing basic MPI file I/O.\n");
      printf("*** testing file create with parallel I/O with MPI...");
   }

   if (MPI_File_open(MPI_COMM_WORLD, FILE, MPI_MODE_RDWR | MPI_MODE_CREATE,
                     MPI_INFO_NULL, &fh) != MPI_SUCCESS) ERR;
   if (MPI_File_seek(fh, my_rank * sizeof(int), MPI_SEEK_SET) != MPI_SUCCESS) ERR;
   if (MPI_File_write(fh, &my_rank, 1, MPI_INT, &status) != MPI_SUCCESS) ERR;
   if (MPI_File_close(&fh) != MPI_SUCCESS) ERR;

   /* Reopen and check the file. */
   if (MPI_File_open(MPI_COMM_WORLD, FILE, MPI_MODE_RDONLY,
                     MPI_INFO_NULL, &fh) != MPI_SUCCESS) ERR;
   if (MPI_File_seek(fh, my_rank * sizeof(int), MPI_SEEK_SET) != MPI_SUCCESS) ERR;
   if (MPI_File_read(fh, &data_in, 1, MPI_INT, &status) != MPI_SUCCESS) ERR;
   if (data_in != my_rank) ERR;
   if (MPI_File_close(&fh) != MPI_SUCCESS) ERR;

   /* Shut down MPI. */
   MPI_Finalize();

   if (my_rank == 0)
   {
      SUMMARIZE_ERR;
      FINAL_RESULTS;
   }
   return 0;
}