openmpi/ompi/mca/sharedfp/sm/sharedfp_sm_iread.c

/*
 * Copyright (c) 2004-2005 The Trustees of Indiana University and Indiana
 *                         University Research and Technology
 *                         Corporation.  All rights reserved.
 * Copyright (c) 2004-2005 The University of Tennessee and The University
 *                         of Tennessee Research Foundation.  All rights
 *                         reserved.
 * Copyright (c) 2004-2005 High Performance Computing Center Stuttgart,
 *                         University of Stuttgart.  All rights reserved.
 * Copyright (c) 2004-2005 The Regents of the University of California.
 *                         All rights reserved.
 * Copyright (c) 2013      University of Houston. All rights reserved.
 * $COPYRIGHT$
 *
 * Additional copyrights may follow
 *
 * $HEADER$
 */


#include "ompi_config.h"
#include "sharedfp_sm.h"

#include "mpi.h"
#include "ompi/constants.h"
#include "ompi/mca/sharedfp/sharedfp.h"

int mca_sharedfp_sm_iread(mca_io_ompio_file_t *fh,
			  void *buf,
			  int count,
			  ompi_datatype_t *datatype,
			  MPI_Request * request)
{
    int ret = OMPI_SUCCESS;
    OMPI_MPI_OFFSET_TYPE offset = 0;
    long bytesRequested = 0;
    size_t numofBytes;
    struct mca_sharedfp_base_data_t *sh = NULL;
    mca_sharedfp_base_module_t * shared_fp_base_module = NULL;

    if( NULL == fh->f_sharedfp_data){
	if ( mca_sharedfp_sm_verbose ) {
	    printf("sharedfp_sm_iread: opening the shared file pointer\n");
	}
        shared_fp_base_module = fh->f_sharedfp;

        ret = shared_fp_base_module->sharedfp_file_open(fh->f_comm,
                                                        fh->f_filename,
                                                        fh->f_amode,
                                                        fh->f_info,
                                                        fh);
        if (  OMPI_SUCCESS != ret ) {
            opal_output(0,"sharedfp_sm_iread - error opening the shared file pointer\n");
            return ret;
        }
    }

    /* Calculate the number of bytes to write */
    opal_datatype_type_size ( &datatype->super, &numofBytes);
    bytesRequested = count * numofBytes;

    /* Retrieve the shared file data struct */
    sh = fh->f_sharedfp_data;

    if ( mca_sharedfp_sm_verbose ) {
	printf("sharedfp_sm_iread: Bytes Requested is %ld\n",bytesRequested);
    }
    /*Request the offset to write bytesRequested bytes*/
    ret = mca_sharedfp_sm_request_position(sh,bytesRequested,&offset);

    if (  -1 != ret ) {
	if ( mca_sharedfp_sm_verbose ) {
	    printf("sharedfp_sm_iread: Offset received is %lld\n",offset);
	}
        /* Read the file */
        ret = ompio_io_ompio_file_iread_at(sh->sharedfh,offset,buf,count,datatype,request);
    }

    return ret;
}

int mca_sharedfp_sm_read_ordered_begin(mca_io_ompio_file_t *fh,
                                       void *buf,
                                       int count,
                                       struct ompi_datatype_t *datatype)
{
    opal_output(0,"mca_sharedfp_sm_read_ordered_begin: NOT IMPLEMENTED\n");
    return OMPI_ERROR;
}


int mca_sharedfp_sm_read_ordered_end(mca_io_ompio_file_t *fh,
				     void *buf,
				     ompi_status_public_t *status)
{
    opal_output(0,"mca_sharedfp_sm_read_ordered_end: NOT IMPLEMENTED\n");
    return OMPI_ERROR;
}