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libs/ck-libs/ampi/romio/adio/common/get_fp_posn.c

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/* -*- Mode: C; c-basic-offset:4 ; -*- */
/* 
 *   $Id$    
 *
 *   Copyright (C) 1997 University of Chicago. 
 *   See COPYRIGHT notice in top-level directory.
 */

#include "adio.h"
#include "adio_extern.h"

/* returns the current position of the individual file pointer
   in etype units relative to the current view. */

void ADIOI_Get_position(ADIO_File fd, ADIO_Offset *offset)
{
    ADIOI_Flatlist_node *flat_file;
    int i, n_filetypes, flag, frd_size;
    int filetype_size, etype_size, filetype_is_contig;
    MPI_Aint filetype_extent;
    ADIO_Offset disp, byte_offset, sum, size_in_file;
    
    ADIOI_Datatype_iscontig(fd->filetype, &filetype_is_contig);
    etype_size = fd->etype_size;

    if (filetype_is_contig){
        printf("filetype is contig: fd->filetype=%d, etypesize=%d\n",fd->filetype,fd->etype_size);
        *offset = (fd->fp_ind - fd->disp)/etype_size;
    } else {
        /* filetype already flattened in ADIO_Open */
        flat_file = ADIOI_Flatlist;
        while (flat_file->type != fd->filetype) flat_file = flat_file->next;

        MPI_Type_size(fd->filetype, &filetype_size);
        MPI_Type_extent(fd->filetype, &filetype_extent);

        printf("filetype is not contig: fd->filetype=%d,size=%d,extent=%d,etypesize=%d\n",fd->filetype,filetype_size,filetype_extent,fd->etype_size);

        disp = fd->disp;
        byte_offset = fd->fp_ind;
        n_filetypes = -1;
        flag = 0;
        while (!flag) {
            sum = 0;
            n_filetypes++;
            for (i=0; i<flat_file->count; i++) {
                sum += flat_file->blocklens[i];
                if (disp + flat_file->indices[i] + 
                    (ADIO_Offset) n_filetypes*filetype_extent + flat_file->blocklens[i] 
                    >= byte_offset) {
                    frd_size = (int) (disp + flat_file->indices[i] + 
                        (ADIO_Offset) n_filetypes*filetype_extent
                        + flat_file->blocklens[i] - byte_offset);
                    sum -= frd_size;
                    flag = 1;
                    break;
                }
            }
        }
        size_in_file = (ADIO_Offset) n_filetypes*filetype_size + sum;
        *offset = size_in_file/etype_size;
    }
}

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