/* -*- Mode: C; c-basic-offset:4 ; -*- */
/* 
 *   $Id: rd_atallb.c,v 1.7 2002/10/24 15:54:42 gropp Exp $    
 *
 *   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_read_at_all_begin = PMPI_File_read_at_all_begin
#elif defined(HAVE_PRAGMA_HP_SEC_DEF)
#pragma _HP_SECONDARY_DEF PMPI_File_read_at_all_begin MPI_File_read_at_all_begin
#elif defined(HAVE_PRAGMA_CRI_DUP)
#pragma _CRI duplicate MPI_File_read_at_all_begin as PMPI_File_read_at_all_begin
/* end of weak pragmas */
#endif

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

/*@
    MPI_File_read_at_all_begin - Begin a split collective read using explict offset

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

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

.N fortran
@*/
int MPI_File_read_at_all_begin(MPI_File fh, MPI_Offset offset, void *buf,
                         int count, MPI_Datatype datatype)
{
    int error_code, datatype_size;
#ifndef PRINT_ERR_MSG
    static char myname[] = "MPI_FILE_READ_AT_ALL_BEGIN";
#endif
    MPI_Status status;

#ifdef PRINT_ERR_MSG
    if ((fh <= (MPI_File) 0) || (fh->cookie != ADIOI_FILE_COOKIE)) {
	FPRINTF(stderr, "MPI_File_read_at_all_begin: Invalid file handle\n");
	MPI_Abort(MPI_COMM_WORLD, 1);
    }
#else
    ADIOI_TEST_FILE_HANDLE(fh, myname);
#endif

    if (offset < 0) {
#ifdef PRINT_ERR_MSG
	FPRINTF(stderr, "MPI_File_read_at_all_begin: Invalid offset argument\n");
	MPI_Abort(MPI_COMM_WORLD, 1);
#else
	error_code = MPIR_Err_setmsg(MPI_ERR_ARG, MPIR_ERR_OFFSET_ARG,
				     myname, (char *) 0, (char *) 0);
	return ADIOI_Error(fh, error_code, myname);	    
#endif
    }

    if (count < 0) {
#ifdef PRINT_ERR_MSG
	FPRINTF(stderr, "MPI_File_read_at_all_begin: Invalid count argument\n");
	MPI_Abort(MPI_COMM_WORLD, 1);
#else
	error_code = MPIR_Err_setmsg(MPI_ERR_ARG, MPIR_ERR_COUNT_ARG,
				     myname, (char *) 0, (char *) 0);
	return ADIOI_Error(fh, error_code, myname);
#endif
    }

    if (datatype == MPI_DATATYPE_NULL) {
#ifdef PRINT_ERR_MSG
        FPRINTF(stderr, "MPI_File_read_at_all_begin: Invalid datatype\n");
        MPI_Abort(MPI_COMM_WORLD, 1);
#else
	error_code = MPIR_Err_setmsg(MPI_ERR_TYPE, MPIR_ERR_TYPE_NULL,
				     myname, (char *) 0, (char *) 0);
	return ADIOI_Error(fh, error_code, myname);	    
#endif
    }

    if (fh->access_mode & MPI_MODE_SEQUENTIAL) {
#ifdef PRINT_ERR_MSG
        FPRINTF(stderr, "MPI_File_read_at_all_begin: Can't use this function because file was opened with MPI_MODE_SEQUENTIAL\n");
        MPI_Abort(MPI_COMM_WORLD, 1);
#else
	error_code = MPIR_Err_setmsg(MPI_ERR_UNSUPPORTED_OPERATION, 
                        MPIR_ERR_AMODE_SEQ, myname, (char *) 0, (char *) 0);
	return ADIOI_Error(fh, error_code, myname);
#endif
    }

    if (fh->split_coll_count) {
#ifdef PRINT_ERR_MSG
        FPRINTF(stderr, "MPI_File_read_at_all_begin: Only one active split collective I/O operation allowed per file handle\n");
        MPI_Abort(MPI_COMM_WORLD, 1);
#else
	error_code = MPIR_Err_setmsg(MPI_ERR_IO, MPIR_ERR_MULTIPLE_SPLIT_COLL,
                              myname, (char *) 0, (char *) 0);
	return ADIOI_Error(fh, error_code, myname);
#endif
    }

    fh->split_coll_count = 1;

    MPI_Type_size(datatype, &datatype_size);
    if ((count*datatype_size) % fh->etype_size != 0) {
#ifdef PRINT_ERR_MSG
        FPRINTF(stderr, "MPI_File_read_at_all_begin: Only an integral number of etypes can be accessed\n");
        MPI_Abort(MPI_COMM_WORLD, 1);
#else
	error_code = MPIR_Err_setmsg(MPI_ERR_IO, MPIR_ERR_ETYPE_FRACTIONAL,
				     myname, (char *) 0, (char *) 0);
	return ADIOI_Error(fh, error_code, myname);	    
#endif
    }

    ADIO_ReadStridedColl(fh, buf, count, datatype, ADIO_EXPLICIT_OFFSET,
			  offset, &status, &error_code);
    return error_code;
}