/* -*- Mode: C; c-basic-offset:4 ; indent-tabs-mode:nil ; -*- */

/*

 *  (C) 2012 by Argonne National Laboratory.

 *      See COPYRIGHT in top-level directory.

 */

#include "mpidimpl.h"

#undef FUNCNAME

#define FUNCNAME MPID_Imrecv

#undef FCNAME

#define FCNAME MPL_QUOTE(FUNCNAME)

int MPID_Mrecv(void *buf, int count, MPI_Datatype datatype,

               MPID_Request *message, MPI_Status *status)

{

    int mpi_errno = MPI_SUCCESS;

    MPI_Request req_handle; /* dummy for MPIR_Request_complete */

    int active_flag; /* dummy for MPIR_Request_complete */

    MPID_Request *rreq = NULL;

    if (message == NULL) {

        /* treat as though MPI_MESSAGE_NO_PROC was passed */

        MPIR_Status_set_procnull(status);

        goto fn_exit;

    }

    /* There is no optimized MPID_Mrecv at this time because there is no real

     * optimization potential in that case.  MPID_Recv exists to prevent

     * creating a request unnecessarily for messages that are already present

     * and eligible for immediate completion. */

    mpi_errno = MPID_Imrecv(buf, count, datatype, message, &rreq);

    if (mpi_errno) MPIR_ERR_POP(mpi_errno);

    if (!MPID_Request_is_complete(rreq)) {

        MPID_Progress_state progress_state;

        MPID_Progress_start(&progress_state);

        while (!MPID_Request_is_complete(rreq))

        {

            mpi_errno = MPID_Progress_wait(&progress_state);

            if (mpi_errno) {

                /* --BEGIN ERROR HANDLING-- */

                MPID_Progress_end(&progress_state);

                MPIR_ERR_POP(mpi_errno);

                /* --END ERROR HANDLING-- */

            }

        }

        MPID_Progress_end(&progress_state);

    }

    mpi_errno = MPIR_Request_complete(&req_handle, rreq, status, &active_flag);

    if (mpi_errno) MPIR_ERR_POP(mpi_errno);

fn_exit:

    return mpi_errno;

fn_fail:

    goto fn_exit;

}