text: /*
   * Copyright (c) 2004-2007 The Trustees of Indiana University and Indiana
   *                         University Research and Technology
   *                         Corporation.  All rights reserved.
   * Copyright (c) 2004-2020 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) 2006      Cisco Systems, Inc.  All rights reserved.
   * Copyright (c) 2015-2017 Research Organization for Information Science
   *                         and Technology (RIST). All rights reserved.
   * Copyright (c) 2017      FUJITSU LIMITED.  All rights reserved.
   * $COPYRIGHT$
   *
   * Additional copyrights may follow
   *
   * $HEADER$
   */
  #include "ompi_config.h"
  #include <stdio.h>
  
  #include "ompi/mpi/c/bindings.h"
  #include "ompi/runtime/params.h"
  #include "ompi/communicator/communicator.h"
  #include "ompi/mca/pml/pml.h"
  #include "ompi/request/request.h"
  #include "ompi/errhandler/errhandler.h"
  #include "ompi/memchecker.h"
  
  #if OMPI_BUILD_MPI_PROFILING
  #if OPAL_HAVE_WEAK_SYMBOLS
  #pragma weak MPI_Start = PMPI_Start
  #endif
  #define MPI_Start PMPI_Start
  #endif
  
  static const char FUNC_NAME[] = "MPI_Start";
  
  
  int MPI_Start(MPI_Request *request)
  {
      int ret = OMPI_SUCCESS;
  
      MEMCHECKER(
          memchecker_request(request);
      );
  
      if ( MPI_PARAM_CHECK ) {
          int rc = MPI_SUCCESS;
          OMPI_ERR_INIT_FINALIZE(FUNC_NAME);
          if (request == NULL) {
              rc = MPI_ERR_REQUEST;
          }
          OMPI_ERRHANDLER_NOHANDLE_CHECK(rc, rc, FUNC_NAME);
      }
      /**
       * Per definition of the handling of persistent request in the
       * MPI standard 3.1 page 78 line 19: we must have the following
       * sequence CREATE (START COMPLETE)* FREE. The upper level is
       * responsible for handling any concurency. The PML must handle
       * this case, as it is the only one knowing if the request can
       * be reused or not (it is PML completed or not?).
       */
  
      switch((*request)->req_type) {
      case OMPI_REQUEST_PML:
      case OMPI_REQUEST_COLL:
          if ( MPI_PARAM_CHECK && !(*request)->req_persistent) {
              return OMPI_ERRHANDLER_NOHANDLE_INVOKE(MPI_ERR_REQUEST, FUNC_NAME);
          }
          OPAL_CR_ENTER_LIBRARY();
  
          ret = (*request)->req_start(1, request);
  
          OPAL_CR_EXIT_LIBRARY();
          return ret;
  
      case OMPI_REQUEST_NOOP:
          /**
           * We deal with a MPI_PROC_NULL request. If the request is
           * already active, fall back to the error case in the default.
           * Otherwise, mark it active so we can correctly handle it in
           * the wait*.
           */
          if( OMPI_REQUEST_INACTIVE == (*request)->req_state ) {
              (*request)->req_state = OMPI_REQUEST_ACTIVE;
              return MPI_SUCCESS;
          }
  
      default:
          return OMPI_ERRHANDLER_NOHANDLE_INVOKE(MPI_ERR_REQUEST, FUNC_NAME);
      }
  }
  
  