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libs/ck-libs/ampi/romio/mpi-io/seek_sh.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_seek_shared = PMPI_File_seek_shared
#elif defined(HAVE_PRAGMA_HP_SEC_DEF)
#pragma _HP_SECONDARY_DEF PMPI_File_seek_shared MPI_File_seek_shared
#elif defined(HAVE_PRAGMA_CRI_DUP)
#pragma _CRI duplicate MPI_File_seek_shared as PMPI_File_seek_shared
/* end of weak pragmas */
#endif

/* Include mapping from MPI->PMPI */
#define MPIO_BUILD_PROFILING
#include "mpioprof.h"
#endif

/*@
    MPI_File_seek_shared - Updates the shared file pointer

Input Parameters:
. fh - file handle (handle)
. offset - file offset (integer)
. whence - update mode (state)

.N fortran
@*/
int MPI_File_seek_shared(MPI_File mpi_fh, MPI_Offset offset, int whence)
{
    int error_code=MPI_SUCCESS, tmp_whence, myrank;
    static char myname[] = "MPI_FILE_SEEK_SHARED";
    MPI_Offset curr_offset, eof_offset, tmp_offset;
    ADIO_File fh;

    MPIU_THREAD_CS_ENTER(ALLFUNC,);

    fh = MPIO_File_resolve(mpi_fh);

    /* --BEGIN ERROR HANDLING-- */
    MPIO_CHECK_FILE_HANDLE(fh, myname, error_code);
    MPIO_CHECK_NOT_SEQUENTIAL_MODE(fh, myname, error_code);
    MPIO_CHECK_FS_SUPPORTS_SHARED(fh, myname, error_code);
    /* --END ERROR HANDLING-- */

    tmp_offset = offset;
    MPI_Bcast(&tmp_offset, 1, ADIO_OFFSET, 0, fh->comm);
    /* --BEGIN ERROR HANDLING-- */
    if (tmp_offset != offset)
    {
    error_code = MPIO_Err_create_code(MPI_SUCCESS, MPIR_ERR_RECOVERABLE,
                      myname, __LINE__, MPI_ERR_ARG,
                      "**notsame", 0);
    error_code = MPIO_Err_return_file(fh, error_code);
    goto fn_exit;
    }
    /* --END ERROR HANDLING-- */

    tmp_whence = whence;
    MPI_Bcast(&tmp_whence, 1, MPI_INT, 0, fh->comm);
    /* --BEGIN ERROR HANDLING-- */
    if (tmp_whence != whence)
    {
    error_code = MPIO_Err_create_code(MPI_SUCCESS, MPIR_ERR_RECOVERABLE,
                      myname, __LINE__, MPI_ERR_ARG,
                      "**iobadwhence", 0);
    error_code = MPIO_Err_return_file(fh, error_code);
    goto fn_exit;
    }
    /* --END ERROR HANDLING-- */

    ADIOI_TEST_DEFERRED(fh, "MPI_File_seek_shared", &error_code);

    MPI_Comm_rank(fh->comm, &myrank);

    if (!myrank)
    {
    switch(whence)
    {
    case MPI_SEEK_SET:
        /* --BEGIN ERROR HANDLING-- */
        if (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-- */
        break;
    case MPI_SEEK_CUR:
        /* get current location of shared file pointer */
        ADIO_Get_shared_fp(fh, 0, &curr_offset, &error_code);
        /* --BEGIN ERROR HANDLING-- */
        if (error_code != MPI_SUCCESS)
        {
        error_code = MPIO_Err_create_code(MPI_SUCCESS,
                          MPIR_ERR_FATAL,
                          myname, __LINE__,
                          MPI_ERR_INTERN, 
                          "**iosharedfailed", 0);
        error_code = MPIO_Err_return_file(fh, error_code);
        goto fn_exit;
        }
        /* --END ERROR HANDLING-- */
        offset += curr_offset;
        /* --BEGIN ERROR HANDLING-- */
        if (offset < 0)
        {
        error_code = MPIO_Err_create_code(MPI_SUCCESS,
                          MPIR_ERR_RECOVERABLE,
                          myname, __LINE__,
                          MPI_ERR_ARG,
                          "**ionegoffset", 0);
        error_code = MPIO_Err_return_file(fh, error_code);
        goto fn_exit;
        }
        /* --END ERROR HANDLING-- */
        break;
    case MPI_SEEK_END:
        /* find offset corr. to end of file */
        ADIOI_Get_eof_offset(fh, &eof_offset);
        offset += eof_offset;
        /* --BEGIN ERROR HANDLING-- */
        if (offset < 0)
        {
        error_code = MPIO_Err_create_code(MPI_SUCCESS,
                          MPIR_ERR_RECOVERABLE,
                          myname, __LINE__,
                          MPI_ERR_ARG,
                          "**ionegoffset", 0);
        error_code = MPIO_Err_return_file(fh, error_code);
        goto fn_exit;
        }
        /* --END ERROR HANDLING-- */
        break;
    default:
        /* --BEGIN ERROR HANDLING-- */
        error_code = MPIO_Err_create_code(MPI_SUCCESS,
                          MPIR_ERR_RECOVERABLE,
                          myname, __LINE__, MPI_ERR_ARG,
                          "**iobadwhence", 0);
        error_code = MPIO_Err_return_file(fh, error_code);
        goto fn_exit;
        /* --END ERROR HANDLING-- */
    }

    ADIO_Set_shared_fp(fh, offset, &error_code);
    /* --BEGIN ERROR HANDLING-- */
    if (error_code != MPI_SUCCESS)
    {
        error_code = MPIO_Err_create_code(MPI_SUCCESS,
                          MPIR_ERR_FATAL,
                          myname, __LINE__,
                          MPI_ERR_INTERN, 
                          "**iosharedfailed", 0);
        error_code = MPIO_Err_return_file(fh, error_code);
        goto fn_exit;
    }
    /* --END ERROR HANDLING-- */

    }

    /* FIXME: explain why the barrier is necessary */
    MPI_Barrier(fh->comm);

    error_code = MPI_SUCCESS;

fn_exit:
    MPIU_THREAD_CS_EXIT(ALLFUNC,);

    return error_code;
}

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