openmpi/ompi/mca/sharedfp/lockedfile/sharedfp_lockedfile_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_lockedfile.h"

#include "mpi.h"
#include "ompi/constants.h"
#include "ompi/mca/sharedfp/sharedfp.h"
#include "ompi/mca/io/ompio/io_ompio.h"

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

    if ( NULL == fh->f_sharedfp_data ) {
	if ( mca_sharedfp_lockedfile_verbose ) {
	    printf("sharedfp_lockedfile_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_lockedfile_iread - error opening the shared file pointer\n");
            return ret;
        }
    }

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

    if ( mca_sharedfp_lockedfile_verbose ) {
	printf("sharedfp_lockedfile_iread - Bytes Requested is %ld\n",bytesRequested);
    }


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

    /*Request the offset to write bytesRequested bytes*/
    ret = mca_sharedfp_lockedfile_request_position(sh,bytesRequested,&offset);
    if ( -1 != ret )  {
	if ( mca_sharedfp_lockedfile_verbose ) {
	    printf("sharedfp_lockedfile_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_lockedfile_read_ordered_begin(mca_io_ompio_file_t *fh,
                                       void *buf,
                                       int count,
                                       struct ompi_datatype_t *datatype)
{
    opal_output(0,"mca_sharedfp_lockedfile_write_ordered_begin: NOT IMPLEMENTED\n");
    return OMPI_ERROR;
}


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