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libs/ck-libs/ampi/romio/mpi-io/iread.c

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

#include "mpioimpl.h"

#ifdef HAVE_WEAK_SYMBOLS

#if defined(HAVE_PRAGMA_WEAK)
#pragma weak MPI_File_iread = PMPI_File_iread
#elif defined(HAVE_PRAGMA_HP_SEC_DEF)
#pragma _HP_SECONDARY_DEF PMPI_File_iread MPI_File_iread
#elif defined(HAVE_PRAGMA_CRI_DUP)
#pragma _CRI duplicate MPI_File_iread as PMPI_File_iread
/* end of weak pragmas */
#endif

/* Include mapping from MPI->PMPI */
#define MPIO_BUILD_PROFILING
#include "mpioprof.h"
#endif
/*@
    MPI_File_iread - Nonblocking read using individual file pointer

Input Parameters:
. fh - file handle (handle)
. count - number of elements in buffer (nonnegative integer)
. datatype - datatype of each buffer element (handle)

Output Parameters:
. buf - initial address of buffer (choice)
. request - request object (handle)

.N fortran
@*/
#ifdef HAVE_MPI_GREQUEST
#include "mpiu_greq.h"
#endif

int MPI_File_iread(MPI_File mpi_fh, void *buf, int count, 
           MPI_Datatype datatype, MPI_Request *request)
{
    int error_code=MPI_SUCCESS;
    static char myname[] = "MPI_FILE_IREAD";
#ifdef MPI_hpux
    int fl_xmpi;

    HPMP_IO_START(fl_xmpi, BLKMPIFILEIREAD, TRDTSYSTEM, mpi_fh, datatype,
          count);
#endif /* MPI_hpux */

    MPIU_THREAD_CS_ENTER(ALLFUNC,);

    error_code = MPIOI_File_iread(mpi_fh, (MPI_Offset) 0, ADIO_INDIVIDUAL,
                  buf, count, datatype, myname, request);
    
    /* --BEGIN ERROR HANDLING-- */
    if (error_code != MPI_SUCCESS)
    error_code = MPIO_Err_return_file(mpi_fh, error_code);
    /* --END ERROR HANDLING-- */

#ifdef MPI_hpux
    HPMP_IO_END(fl_xmpi, mpi_fh, datatype, count);
#endif /* MPI_hpux */
    MPIU_THREAD_CS_EXIT(ALLFUNC,);

    return error_code;
}

/* prevent multiple definitions of this routine */
// #ifdef MPIO_BUILD_PROFILING
int MPIOI_File_iread(MPI_File mpi_fh,
             MPI_Offset offset,
             int file_ptr_type,
             void *buf,
             int count,
             MPI_Datatype datatype,
             char *myname,
             MPI_Request *request)
{
    int error_code, bufsize, buftype_is_contig, filetype_is_contig;
    int datatype_size;
    ADIO_Status status;
    ADIO_File fh;
    ADIO_Offset off;
    MPI_Offset nbytes=0;

    fh = MPIO_File_resolve(mpi_fh);

    /* --BEGIN ERROR HANDLING-- */
    MPIO_CHECK_FILE_HANDLE(fh, myname, error_code);
    MPIO_CHECK_COUNT(fh, count, myname, error_code);
    MPIO_CHECK_DATATYPE(fh, datatype, myname, error_code);

    if (file_ptr_type == ADIO_EXPLICIT_OFFSET && offset < 0) {
    error_code = MPIO_Err_create_code(MPI_SUCCESS, MPIR_ERR_RECOVERABLE,
                      myname, __LINE__, MPI_ERR_ARG,
                      "**iobadoffset", 0);
    error_code = MPIO_Err_return_file(fh, error_code);
    goto fn_exit;
    }
    /* --END ERROR HANDLING-- */

    MPI_Type_size(datatype, &datatype_size);

    /* --BEGIN ERROR HANDLING-- */
    MPIO_CHECK_INTEGRAL_ETYPE(fh, count, datatype_size, myname, error_code);
    MPIO_CHECK_READABLE(fh, myname, error_code);
    MPIO_CHECK_NOT_SEQUENTIAL_MODE(fh, myname, error_code);
    MPIO_CHECK_COUNT_SIZE(fh, count, datatype_size, myname, error_code);
    /* --END ERROR HANDLING-- */

    ADIOI_Datatype_iscontig(datatype, &buftype_is_contig);
    ADIOI_Datatype_iscontig(fh->filetype, &filetype_is_contig);

    ADIOI_TEST_DEFERRED(fh, myname, &error_code);

    if (buftype_is_contig && filetype_is_contig) {
    /* convert count and offset to bytes */
    bufsize = datatype_size * count;

    if (file_ptr_type == ADIO_EXPLICIT_OFFSET) {
        off = fh->disp + fh->etype_size * offset;
    }
    else {
        off = fh->fp_ind;
    }

        if (!(fh->atomicity))
        ADIO_IreadContig(fh, buf, count, datatype, file_ptr_type,
            off, request, &error_code); 
        else {
            /* to maintain strict atomicity semantics with other concurrent
              operations, lock (exclusive) and call blocking routine */
        if (ADIO_Feature(fh, ADIO_LOCKS))
        {
                ADIOI_WRITE_LOCK(fh, off, SEEK_SET, bufsize);
        }

            ADIO_ReadContig(fh, buf, count, datatype, file_ptr_type, 
                off, &status, &error_code);

        if (ADIO_Feature(fh, ADIO_LOCKS)) 
        {
                ADIOI_UNLOCK(fh, off, SEEK_SET, bufsize);
        }
        if (error_code == MPI_SUCCESS) {
        nbytes = count*datatype_size;
        }
        MPIO_Completed_request_create(&fh, nbytes, &error_code, request);
        }
    }
    else ADIO_IreadStrided(fh, buf, count, datatype, file_ptr_type,
               offset, request, &error_code); 

fn_exit:

    return error_code;
}
// #endif

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