#include <sys/stat.h>
#include <errno.h>
#include "mpi.h"

MPI_File
NSSCreateLustreFile(
  MPI_Comm        comm,
  const char*     path,
  int             stripeCount,
  size_t          stripeSize,
  int             *errorCode
)
{
  struct stat     fInfo;
  
  if ( stat(path, &fInfo) != 0 ) {
    int           rc = 0;
    MPI_File      fh = NULL;
    MPI_Info      finfo = NULL;
    
    if ( (rc = MPI_Info_create(&finfo)) == 0 ) {
      char        strForm[32];
      
      if ( stripeCount < 0 ) stripeCount = -1;
      snprintf(strForm, sizeof(strForm), "%d", stripeCount);
      if ( (rc = MPI_Info_set(finfo, "striping_factor", strForm)) == 0 ) {
        if ( stripeSize < 0 ) stripeSize = 0;
        snprintf(strForm, sizeof(strForm), "%ld", stripeSize);
        if ( (rc = MPI_Info_set(finfo, "striping_unit", strForm)) == 0 ) {
          rc = MPI_File_open(
                    comm,
                    (char*)path,
                    MPI_MODE_RDWR | MPI_MODE_CREATE,
                    finfo,
                    &fh
                  );
        }
      }
      MPI_Info_free(&finfo);
    }
    if ( rc ) {
      if ( errorCode ) *errorCode = rc;
      return NULL;
    }
    return fh;
  } else {
    if ( errorCode ) *errorCode = EEXIST;
  }
  return NULL;
}