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

/*

 *

 *  (C) 2001 by Argonne National Laboratory.

 *      See COPYRIGHT in top-level directory.

 */

#include "mpiimpl.h"

/* -- Begin Profiling Symbol Block for routine MPI_Sendrecv_replace */

#if defined(HAVE_PRAGMA_WEAK)

#pragma weak MPI_Sendrecv_replace = PMPI_Sendrecv_replace

#elif defined(HAVE_PRAGMA_HP_SEC_DEF)

#pragma _HP_SECONDARY_DEF PMPI_Sendrecv_replace  MPI_Sendrecv_replace

#elif defined(HAVE_PRAGMA_CRI_DUP)

#pragma _CRI duplicate MPI_Sendrecv_replace as PMPI_Sendrecv_replace

#elif defined(HAVE_WEAK_ATTRIBUTE)

int MPI_Sendrecv_replace(void *buf, int count, MPI_Datatype datatype, int dest,

                         int sendtag, int source, int recvtag, MPI_Comm comm, MPI_Status * status)

    __attribute__ ((weak, alias("PMPI_Sendrecv_replace")));

#endif

/* -- End Profiling Symbol Block */

/* Define MPICH_MPI_FROM_PMPI if weak symbols are not supported to build

   the MPI routines */

#ifndef MPICH_MPI_FROM_PMPI

#undef MPI_Sendrecv_replace

#define MPI_Sendrecv_replace PMPI_Sendrecv_replace

#endif

#undef FUNCNAME

#define FUNCNAME MPI_Sendrecv_replace

#undef FCNAME

#define FCNAME MPL_QUOTE(FUNCNAME)

/*@

    MPI_Sendrecv_replace - Sends and receives using a single buffer

Input Parameters:

+ count - number of elements in send and receive buffer (integer)

. datatype - type of elements in send and receive buffer (handle)

. dest - rank of destination (integer)

. sendtag - send message tag (integer)

. source - rank of source (integer)

. recvtag - receive message tag (integer)

- comm - communicator (handle)

Output Parameters:

+ buf - initial address of send and receive buffer (choice)

- status - status object (Status)

.N ThreadSafe

.N Fortran

.N FortranStatus

.N Errors

.N MPI_SUCCESS

.N MPI_ERR_COMM

.N MPI_ERR_COUNT

.N MPI_ERR_TYPE

.N MPI_ERR_TAG

.N MPI_ERR_RANK

.N MPI_ERR_TRUNCATE

.N MPI_ERR_EXHAUSTED

@*/

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

                         int dest, int sendtag, int source, int recvtag,

                         MPI_Comm comm, MPI_Status * status)

{

    int mpi_errno = MPI_SUCCESS;

    MPIR_Comm *comm_ptr = NULL;

    MPIR_CHKLMEM_DECL(1);

    MPIR_FUNC_TERSE_STATE_DECL(MPID_STATE_MPI_SENDRECV_REPLACE);

    MPIR_ERRTEST_INITIALIZED_ORDIE();

    MPID_THREAD_CS_ENTER(GLOBAL, MPIR_THREAD_GLOBAL_ALLFUNC_MUTEX);

    MPIR_FUNC_TERSE_PT2PT_ENTER_BOTH(MPID_STATE_MPI_SENDRECV_REPLACE);

    /* Convert handles to MPI objects. */

    MPIR_Comm_get_ptr(comm, comm_ptr);

#ifdef HAVE_ERROR_CHECKING

    {

        MPID_BEGIN_ERROR_CHECKS;

        {

            /* Validate communicator */

            MPIR_Comm_valid_ptr(comm_ptr, mpi_errno, FALSE);

            if (mpi_errno)

                goto fn_fail;

            /* Validate count */

            MPIR_ERRTEST_COUNT(count, mpi_errno);

            /* Validate status (status_ignore is not the same as null) */

            MPIR_ERRTEST_ARGNULL(status, "status", mpi_errno);

            /* Validate tags */

            MPIR_ERRTEST_SEND_TAG(sendtag, mpi_errno);

            MPIR_ERRTEST_RECV_TAG(recvtag, mpi_errno);

            /* Validate source and destination */

            MPIR_ERRTEST_SEND_RANK(comm_ptr, dest, mpi_errno);

            MPIR_ERRTEST_RECV_RANK(comm_ptr, source, mpi_errno);

            /* Validate datatype handle */

            MPIR_ERRTEST_DATATYPE(datatype, "datatype", mpi_errno);

            /* Validate datatype object */

            if (HANDLE_GET_KIND(datatype) != HANDLE_KIND_BUILTIN) {

                MPIR_Datatype *datatype_ptr = NULL;

                MPIR_Datatype_get_ptr(datatype, datatype_ptr);

                MPIR_Datatype_valid_ptr(datatype_ptr, mpi_errno);

                if (mpi_errno)

                    goto fn_fail;

                MPIR_Datatype_committed_ptr(datatype_ptr, mpi_errno);

                if (mpi_errno)

                    goto fn_fail;

            }

            /* Validate buffer */

            MPIR_ERRTEST_USERBUFFER(buf, count, datatype, mpi_errno);

        }

        MPID_END_ERROR_CHECKS;

    }

#endif /* HAVE_ERROR_CHECKING */

    /* ... body of routine ... */

#if defined(MPID_Sendrecv_replace)

    {

        mpi_errno = MPID_Sendrecv_replace(buf, count, datatype, dest,

                                          sendtag, source, recvtag, comm_ptr, status)

    }

#else

    {

        MPIR_Request *sreq = NULL;

        MPIR_Request *rreq = NULL;

        void *tmpbuf = NULL;

        MPI_Aint tmpbuf_size = 0;

        MPI_Aint tmpbuf_count = 0;

        if (count > 0 && dest != MPI_PROC_NULL) {

            MPIR_Pack_size_impl(count, datatype, &tmpbuf_size);

            MPIR_CHKLMEM_MALLOC_ORJUMP(tmpbuf, void *, tmpbuf_size, mpi_errno,

                                       "temporary send buffer", MPL_MEM_BUFFER);

            mpi_errno = MPIR_Pack_impl(buf, count, datatype, tmpbuf, tmpbuf_size, &tmpbuf_count);

            if (mpi_errno != MPI_SUCCESS)

                goto fn_fail;

        }

        mpi_errno = MPID_Irecv(buf, count, datatype, source, recvtag,

                               comm_ptr, MPIR_CONTEXT_INTRA_PT2PT, &rreq);

        if (mpi_errno != MPI_SUCCESS)

            goto fn_fail;

        mpi_errno = MPID_Isend(tmpbuf, tmpbuf_count, MPI_PACKED, dest,

                               sendtag, comm_ptr, MPIR_CONTEXT_INTRA_PT2PT, &sreq);

        if (mpi_errno != MPI_SUCCESS) {

            /* --BEGIN ERROR HANDLING-- */

            if (mpi_errno == MPIX_ERR_NOREQ)

                MPIR_ERR_SET(mpi_errno, MPI_ERR_OTHER, "**nomem");

            /* FIXME: should we cancel the pending (possibly completed) receive request or wait for it to complete? */

            MPIR_Request_free(rreq);

            goto fn_fail;

            /* --END ERROR HANDLING-- */

        }

        mpi_errno = MPID_Wait(rreq, MPI_STATUS_IGNORE);

        if (mpi_errno)

            MPIR_ERR_POP(mpi_errno);

        mpi_errno = MPID_Wait(sreq, MPI_STATUS_IGNORE);

        if (mpi_errno)

            MPIR_ERR_POP(mpi_errno);

        if (status != MPI_STATUS_IGNORE) {

            *status = rreq->status;

        }

        if (mpi_errno == MPI_SUCCESS) {

            mpi_errno = rreq->status.MPI_ERROR;

            if (mpi_errno == MPI_SUCCESS) {

                mpi_errno = sreq->status.MPI_ERROR;

            }

        }

        MPIR_Request_free(sreq);

        MPIR_Request_free(rreq);

    }

#endif

    if (mpi_errno != MPI_SUCCESS)

        goto fn_fail;

    /* ... end of body of routine ... */

  fn_exit:

    MPIR_CHKLMEM_FREEALL();

    MPIR_FUNC_TERSE_PT2PT_EXIT_BOTH(MPID_STATE_MPI_SENDRECV_REPLACE);

    MPID_THREAD_CS_EXIT(GLOBAL, MPIR_THREAD_GLOBAL_ALLFUNC_MUTEX);

    return mpi_errno;

  fn_fail:

    /* --BEGIN ERROR HANDLING-- */

#ifdef HAVE_ERROR_CHECKING

    {

        mpi_errno =

            MPIR_Err_create_code(mpi_errno, MPIR_ERR_RECOVERABLE, FCNAME, __LINE__, MPI_ERR_OTHER,

                                 "**mpi_sendrecv_replace",

                                 "**mpi_sendrecv_replace %p %d %D %i %t %i %t %C %p", buf, count,

                                 datatype, dest, sendtag, source, recvtag, comm, status);

    }

#endif

    mpi_errno = MPIR_Err_return_comm(comm_ptr, FCNAME, mpi_errno);

    goto fn_exit;

    /* --END ERROR HANDLING-- */

}