text: /*
   * Copyright (c) 2004-2007 The Trustees of Indiana University and Indiana
   *                         University Research and Technology
   *                         Corporation.  All rights reserved.
   * Copyright (c) 2004-2010 The University of Tennessee and The University
   *                         of Tennessee Research Foundation.  All rights
   *                         reserved.
   * Copyright (c) 2004-2008 High Performance Computing Center Stuttgart, 
   *                         University of Stuttgart.  All rights reserved.
   * Copyright (c) 2004-2005 The Regents of the University of California.
   *                         All rights reserved.
   * Copyright (c) 2010      Oracle and/or its affiliates.  All rights reserved.
   * $COPYRIGHT$
   * 
   * Additional copyrights may follow
   * 
   * $HEADER$
   */
  #include "ompi_config.h"
  
  #include "ompi/mpi/c/bindings.h"
  #include "ompi/runtime/params.h"
  #include "ompi/communicator/communicator.h"
  #include "ompi/errhandler/errhandler.h"
  #include "ompi/datatype/ompi_datatype.h"
  #include "opal/datatype/opal_convertor.h"
  #include "ompi/mca/pml/pml.h"
  #include "ompi/proc/proc.h"
  #include "ompi/memchecker.h"
  
  #if OPAL_HAVE_WEAK_SYMBOLS && OMPI_PROFILING_DEFINES
  #pragma weak MPI_Sendrecv_replace = PMPI_Sendrecv_replace
  #endif
  
  #if OMPI_PROFILING_DEFINES
  #include "ompi/mpi/c/profile/defines.h"
  #endif
  
  static const char FUNC_NAME[] = "MPI_Sendrecv_replace";
  
  
  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 rc = MPI_SUCCESS;
  
      MEMCHECKER(
          memchecker_datatype(datatype);
          memchecker_call(&opal_memchecker_base_isdefined, buf, count, datatype);
          memchecker_comm(comm);
      );
  
      if ( MPI_PARAM_CHECK ) {
          rc = MPI_SUCCESS;
          OMPI_ERR_INIT_FINALIZE(FUNC_NAME);
          OMPI_CHECK_DATATYPE_FOR_RECV(rc, datatype, count);
  
          if (ompi_comm_invalid(comm)) {
              return OMPI_ERRHANDLER_INVOKE(MPI_COMM_WORLD, MPI_ERR_COMM, FUNC_NAME);
          } else if (dest != MPI_PROC_NULL && ompi_comm_peer_invalid(comm, dest)) {
              rc = MPI_ERR_RANK;
          } else if (sendtag < 0 || sendtag > mca_pml.pml_max_tag) {
              rc = MPI_ERR_TAG;
          } else if (source != MPI_PROC_NULL && source != MPI_ANY_SOURCE && ompi_comm_peer_invalid(comm, source)) {
              rc = MPI_ERR_RANK;
          } else if (((recvtag < 0) && (recvtag !=  MPI_ANY_TAG)) || (recvtag > mca_pml.pml_max_tag)) {
              rc = MPI_ERR_TAG;
          }
          OMPI_ERRHANDLER_CHECK(rc, comm, rc, FUNC_NAME);
      }
  
      OPAL_CR_ENTER_LIBRARY();
  
      /* simple case */
      if ( source == MPI_PROC_NULL || dest == MPI_PROC_NULL || count == 0 ) {
          rc = MPI_Sendrecv(buf,count,datatype,dest,sendtag,buf,count,datatype,source,recvtag,comm,status);
  
          OPAL_CR_EXIT_LIBRARY();
          return rc;
      } else {
  
          opal_convertor_t convertor;
          struct iovec iov;
          unsigned char recv_data[2048];
          size_t packed_size, max_data;
          uint32_t iov_count;
          ompi_status_public_t recv_status;
          ompi_proc_t* proc = ompi_comm_peer_lookup(comm,dest);
          if(proc == NULL) {
              rc = MPI_ERR_RANK;
              OMPI_ERRHANDLER_RETURN(rc, comm, rc, FUNC_NAME);
          }
  
          /* initialize convertor to unpack recv buffer */
          OBJ_CONSTRUCT(&convertor, opal_convertor_t);
          opal_convertor_copy_and_prepare_for_recv( proc->proc_convertor, &(datatype->super),
                                                    count, buf, 0, &convertor );
  
          /* setup a buffer for recv */
          opal_convertor_get_packed_size( &convertor, &packed_size );
          if( packed_size > sizeof(recv_data) ) {
              rc = MPI_Alloc_mem(packed_size, MPI_INFO_NULL, &iov.iov_base);
              if(OMPI_SUCCESS != rc) {
                  OMPI_ERRHANDLER_RETURN(OMPI_ERR_OUT_OF_RESOURCE, comm, MPI_ERR_BUFFER, FUNC_NAME);
              }
          } else {
              iov.iov_base = (caddr_t)recv_data;
          }
  
          /* recv into temporary buffer */
          rc = MPI_Sendrecv( buf, count, datatype, dest, sendtag, iov.iov_base, packed_size, 
                             MPI_BYTE, source, recvtag, comm, &recv_status );
          if (rc != MPI_SUCCESS) {
              if(packed_size > sizeof(recv_data))
                  MPI_Free_mem(iov.iov_base);
              OBJ_DESTRUCT(&convertor);
              OMPI_ERRHANDLER_RETURN(rc, comm, rc, FUNC_NAME);
          }
  
          /* unpack into users buffer */
          iov.iov_len = recv_status._ucount;
          iov_count = 1;
          max_data = recv_status._ucount;
          opal_convertor_unpack(&convertor, &iov, &iov_count, &max_data );
  
          /* return status to user */
          if(status != MPI_STATUS_IGNORE) {
              OMPI_STATUS_SET(status, &recv_status);
          }
  
          /* release resources */
          if(packed_size > sizeof(recv_data)) {
              MPI_Free_mem(iov.iov_base);
          }
          OBJ_DESTRUCT(&convertor);
  
          OPAL_CR_EXIT_LIBRARY();
          return MPI_SUCCESS;
      }
  }
  