ad_nfs_iread.c

mpi并行计算的c++代码 可用vc或gcc编译通过 可以用来搭建并行计算试验环境

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

#include "ad_nfs.h"

void ADIOI_NFS_IreadContig(ADIO_File fd, void *buf, int count, 
			   MPI_Datatype datatype, int file_ptr_type,
			   ADIO_Offset offset, ADIO_Request *request,
			   int *error_code)  
{
    int len, typesize;
#ifndef ROMIO_HAVE_WORKING_AIO
    ADIO_Status status;
#else
    int aio_errno = 0;
    static char myname[] = "ADIOI_NFS_IREADCONTIG";
#endif

    (*request) = ADIOI_Malloc_request();
    (*request)->optype = ADIOI_READ;
    (*request)->fd = fd;
    (*request)->datatype = datatype;

    MPI_Type_size(datatype, &typesize);
    len = count * typesize;

#ifndef ROMIO_HAVE_WORKING_AIO
    /* no support for nonblocking I/O. Use blocking I/O. */

    ADIOI_NFS_ReadContig(fd, buf, len, MPI_BYTE, file_ptr_type, offset, 
                         &status, error_code);  
    (*request)->queued = 0;
#ifdef HAVE_STATUS_SET_BYTES
    if (*error_code == MPI_SUCCESS) {
	MPI_Get_elements(&status, MPI_BYTE, &len);
	(*request)->nbytes = len;
    }
#endif

    fd->fp_sys_posn = -1;

#else
    if (file_ptr_type == ADIO_INDIVIDUAL) offset = fd->fp_ind;
    aio_errno = ADIOI_NFS_aio(fd, buf, len, offset, 0, &((*request)->handle));
    if (file_ptr_type == ADIO_INDIVIDUAL) fd->fp_ind += len;

    (*request)->queued = 1;
    ADIOI_Add_req_to_list(request);

    fd->fp_sys_posn = -1;

    if (aio_errno != 0) {
	/* --BEGIN ERROR HANDLING-- */
	MPIO_ERR_CREATE_CODE_ERRNO(myname, aio_errno, error_code);
	return;
	/* --END ERROR HANDLING-- */
    }
    else *error_code = MPI_SUCCESS;
#endif

    fd->async_count++;
}