libs/relay/conduit_relay_io_handle.cpp

// Copyright (c) Lawrence Livermore National Security, LLC and other Conduit
// Project developers. See top-level LICENSE AND COPYRIGHT files for dates and
// other details. No copyright assignment is required to contribute to Conduit.

//-----------------------------------------------------------------------------
///
/// file: conduit_relay_io_handle.cpp
///
//-----------------------------------------------------------------------------

#ifdef CONDUIT_RELAY_IO_MPI_ENABLED
    // FIXME:
    #include "conduit_relay_io_handle.hpp"
#else
    #include "conduit_relay_io_handle.hpp"
#endif

#include "conduit_relay_io.hpp"

#include "conduit_relay_io_handle_sidre.hpp"

#ifdef CONDUIT_RELAY_IO_HDF5_ENABLED
    #include "conduit_relay_io_hdf5.hpp"
#endif


//-----------------------------------------------------------------------------
// standard lib includes
//-----------------------------------------------------------------------------

//-----------------------------------------------------------------------------
// -- begin conduit:: --
//-----------------------------------------------------------------------------
namespace conduit
{

//-----------------------------------------------------------------------------
// -- begin conduit::relay --
//-----------------------------------------------------------------------------
namespace relay
{

#ifdef CONDUIT_RELAY_IO_MPI_ENABLED
//-----------------------------------------------------------------------------
// -- begin conduit::relay::mpi --
//-----------------------------------------------------------------------------
namespace mpi
{
#endif

//-----------------------------------------------------------------------------
// -- begin conduit::relay::<mpi>::io --
//-----------------------------------------------------------------------------
namespace io
{


//-----------------------------------------------------------------------------
// BasicHandle -- IO Handle implementation for built-in protocols
//-----------------------------------------------------------------------------
class BasicHandle: public IOHandle::HandleInterface
{
public:
    BasicHandle(const std::string &path,
                const std::string &protocol,
                const Node &options);
    virtual ~BasicHandle();

    void open();

    bool is_open() const;

    // main interface methods
    void read(Node &node);
    void read(Node &node, const Node &opts);
    void read(const std::string &path,
              Node &node);
    void read(const std::string &path,
              Node &node,
              const Node &opts);

    void write(const Node &node);
    void write(const Node &node, const Node &opts);
    void write(const Node &node,
               const std::string &path);
    void write(const Node &node,
               const std::string &path,
               const Node &opts);

    void remove(const std::string &path);

    void list_child_names(std::vector<std::string> &res);
    void list_child_names(const std::string &path,
                          std::vector<std::string> &res);

    bool has_path(const std::string &path);

    void close();

private:
    Node m_node;
    bool m_open;

};


//-----------------------------------------------------------------------------
// HDF5Handle -- IO Handle implementation for HDF5
//-----------------------------------------------------------------------------
#ifdef CONDUIT_RELAY_IO_HDF5_ENABLED
//-----------------------------------------------------------------------------
class HDF5Handle: public IOHandle::HandleInterface
{
public:
    HDF5Handle(const std::string &path,
               const std::string &protocol,
               const Node &options);
    virtual ~HDF5Handle();

    void open();

    bool is_open() const;

    // main interface methods
    void read(Node &node);
    void read(Node &node, const Node &opts);
    void read(const std::string &path,
              Node &node);
    void read(const std::string &path,
              Node &node,
              const Node &opts);

    void write(const Node &node);
    void write(const Node &node, const Node &opts);
    void write(const Node &node,
               const std::string &path);
    void write(const Node &node,
               const std::string &path,
               const Node &opts);

    void remove(const std::string &path);

    void list_child_names(std::vector<std::string> &res);
    void list_child_names(const std::string &path,
                          std::vector<std::string> &res);

    bool has_path(const std::string &path);

    void close();

private:
    hid_t m_h5_id;

};
//-----------------------------------------------------------------------------
#endif
//-----------------------------------------------------------------------------


//-----------------------------------------------------------------------------
// HandleInterface Implementation
//-----------------------------------------------------------------------------

//-----------------------------------------------------------------------------
IOHandle::HandleInterface::HandleInterface(const std::string &path,
                                           const std::string &protocol,
                                           const Node &options)
: m_path(path),
  m_protocol(protocol),
  m_options(options)
{
    // empty
}

//-----------------------------------------------------------------------------
IOHandle::HandleInterface::~HandleInterface()
{
    // empty
}


//-----------------------------------------------------------------------------
void
IOHandle::HandleInterface::open()
{
    // checks for subpaths, which we don't currently support

    std::string file_path;
    std::string subpath;

    // check for ":" split
    conduit::utils::split_file_path(path(),
                                    std::string(":"),
                                    file_path,
                                    subpath);
    if( !subpath.empty() )
    {
        CONDUIT_ERROR("IOHandle does not support opening paths with "
                      "subpaths specified: \"" << path() << "\"");
    }

    m_open_mode = "rwa"; // default to rw, append

    m_open_mode_read     = true;
    m_open_mode_write    = true;
    m_open_mode_append   = true;
    m_open_mode_truncate = false;

    // check if options includes open mode
    if(options().has_child("mode") && options()["mode"].dtype().is_string())
    {
        std::string opts_mode = options()["mode"].as_string();

        m_open_mode = "";

        m_open_mode_read     = false;
        m_open_mode_write    = false;
        m_open_mode_append   = false;
        m_open_mode_truncate = false;

        if(opts_mode.find("r") != std::string::npos)
        {
            m_open_mode += "r";
            m_open_mode_read = true;
        }

        if(opts_mode.find("w") != std::string::npos)
        {
            m_open_mode += "w";
            m_open_mode_write = true;
        }

        // we need at least read or write
        if(! m_open_mode_read && ! m_open_mode_write)
        {
            CONDUIT_ERROR("IOHandle: invalid open mode:"
                          << "\"" << opts_mode << "\"."
                          << " 'mode' string must provide"
                          << " 'r' (read) and/or 'w' (write)."
                          << " Expected string: {rw}{a|t}");
        }

        // note append and truncate are mut-ex.
        if(opts_mode.find("a") != std::string::npos)
        {
            if( opts_mode.find("t") != std::string::npos )
            {
                CONDUIT_ERROR("IOHandle: invalid open mode:"
                              << "\"" << opts_mode << "\"."
                              << " In 'mode' string "
                              << " 'a' (append) and 't' (truncate)"
                              << " cannot be used together."
                              << " Expected string: {rw}{a|t}");
            }
            m_open_mode += "a";
            m_open_mode_append = true;
        }

        // we checked for both above, so it's safe just check for t here
        if(opts_mode.find("t") != std::string::npos)
        {
            m_open_mode += "t";
            m_open_mode_truncate = true;
        }

        if( !m_open_mode_append && !m_open_mode_truncate)
        {
            // if neither append or truncate were specified,
            // default to append
            m_open_mode += "a";
            m_open_mode_append = true;
        }
    }
}


//-----------------------------------------------------------------------------
IOHandle::HandleInterface *
IOHandle::HandleInterface::create(const std::string &path)
{
    std::string protocol;
    Node options;
    return create(path,protocol,options);
}

//-----------------------------------------------------------------------------
IOHandle::HandleInterface *
IOHandle::HandleInterface::create(const std::string &path,
                                  const std::string &protocol)
{
    Node options;
    return create(path,protocol,options);
}

//-----------------------------------------------------------------------------
IOHandle::HandleInterface *
IOHandle::HandleInterface::create(const std::string &path,
                                  const Node &options)
{
    std::string protocol;
    return create(path,protocol,options);
}

//-----------------------------------------------------------------------------
IOHandle::HandleInterface *
IOHandle::HandleInterface::create(const std::string &path,
                                  const std::string &protocol_,
                                  const Node &options)
{
    HandleInterface *res = NULL;
    std::string protocol = protocol_;

    // allow empty protocol to be used for auto detect
    if(protocol.empty())
    {
        conduit::relay::io::identify_protocol(path,protocol);
    }

    if(protocol == "conduit_bin" ||
       protocol == "json" ||
       protocol == "conduit_json" ||
       protocol == "conduit_base64_json" ||
       protocol == "yaml" )
    {
        res = new BasicHandle(path, protocol, options);
    }
    else if( protocol == "sidre_hdf5" )
    {
        // magic interface
        // path is the path to the root file
        res = new SidreIOHandle(path,protocol,options);
    }
    else if( protocol == "hdf5" )
    {
    #ifdef CONDUIT_RELAY_IO_HDF5_ENABLED
        res = new HDF5Handle(path, protocol, options);
    #else
        CONDUIT_ERROR("conduit_relay lacks HDF5 support: " <<
                      "Cannot create Relay I/O Handle for HDF5" << path);
    #endif
    }
    else
    {
        CONDUIT_ERROR("Relay I/O Handle does not support the protocol: "
                      << protocol);
    }
    return res;
}

//-----------------------------------------------------------------------------
const std::string &
IOHandle::HandleInterface::path() const
{
    return m_path;
}

//-----------------------------------------------------------------------------
const std::string &
IOHandle::HandleInterface::protocol() const
{
    return m_protocol;
}

//-----------------------------------------------------------------------------
const std::string &
IOHandle::HandleInterface::open_mode() const
{
    return m_open_mode;
}

//-----------------------------------------------------------------------------
const Node &
IOHandle::HandleInterface::options() const
{
    return m_options;
}


//-----------------------------------------------------------------------------
// BasicHandle Implementation
//-----------------------------------------------------------------------------
BasicHandle::BasicHandle(const std::string &path,
                         const std::string &protocol,
                         const Node &options)
: HandleInterface(path,protocol,options),
  m_node(),
  m_open(false)
{
    // empty
}
//-----------------------------------------------------------------------------
BasicHandle::~BasicHandle()
{
    close();
}

//-----------------------------------------------------------------------------
void
BasicHandle::open()
{
    close();
    // call base class method, which does final sanity checks
    HandleInterface::open();

    // read from file if it already exists, other wise
    // we start out with a blank slate
    if( utils::is_file( path() ) )
    {
        // read if handle is not 'write' only and we aren't truncating
        if( open_mode_read() && !open_mode_truncate() )
        {
            // read from file
            io::load(path(),
                     protocol(),
                     options(),
                     m_node);
        }
        else
        {
            m_node.reset();
        }
    }
    else if( open_mode_read_only() ) // fail on read only if file doesn't exist
    {
        CONDUIT_ERROR("path: \""
                      << path()
                      << "\" does not exist, cannot open read only "
                      << "(mode = '" << open_mode() << "')");
    }
    else
    {
        // make sure we can actually write to this location
        // we don't want to fail on close if the path
        // is bogus
        io::save(m_node,
                 path(),
                 protocol(),
                 options());
    }

    m_open = true;
}

//-----------------------------------------------------------------------------
bool
BasicHandle::is_open() const
{
    return m_open;
}

//-----------------------------------------------------------------------------
void
BasicHandle::read(Node &node)
{
    Node opts;
    read(node, opts);
}

//-----------------------------------------------------------------------------
void
BasicHandle::read(Node &node, const Node& opts)
{
    CONDUIT_UNUSED(opts);
    // note: wrong mode errors are handled before dispatch to interface

    node.update(m_node);
}

//-----------------------------------------------------------------------------
void
BasicHandle::read(const std::string &path,
                  Node &node)
{
    Node opts;
    read(path, node, opts);
}

//-----------------------------------------------------------------------------
void
BasicHandle::read(const std::string &path,
                  Node &node,
                  const Node &opts)
{
    CONDUIT_UNUSED(opts);
    // note: wrong mode errors are handled before dispatch to interface

    if(m_node.has_path(path))
    {
        node.update(m_node[path]);
    }
}

//-----------------------------------------------------------------------------
void
BasicHandle::write(const Node &node)
{
    Node opts;
    write(node, opts);
}

//-----------------------------------------------------------------------------
void
BasicHandle::write(const Node &node,
                   const Node &opts)
{
    CONDUIT_UNUSED(opts);
    // note: wrong mode errors are handled before dispatch to interface

    m_node.update(node);
}


//-----------------------------------------------------------------------------
void
BasicHandle::write(const Node &node,
                   const std::string &path)
{
    Node opts;
    write(node, path, opts);
}

//-----------------------------------------------------------------------------
void
BasicHandle::write(const Node &node,
                   const std::string &path,
                   const Node& opts)
{
    CONDUIT_UNUSED(opts);
    // note: wrong mode errors are handled before dispatch to interface

    m_node[path].update(node);
}

//-----------------------------------------------------------------------------
void
BasicHandle::list_child_names(std::vector<std::string> &res)
{
    // note: wrong mode errors are handled before dispatch to interface

    res = m_node.child_names();
}

//-----------------------------------------------------------------------------
void
BasicHandle::list_child_names(const std::string &path,
                              std::vector<std::string> &res)
{
    // note: wrong mode errors are handled before dispatch to interface

    res.clear();
    if(m_node.has_path(path))
        res = m_node[path].child_names();
}

//-----------------------------------------------------------------------------
void
BasicHandle::remove(const std::string &path)
{
    // note: wrong mode errors are handled before dispatch to interface

    m_node.remove(path);
}

//-----------------------------------------------------------------------------
bool
BasicHandle::has_path(const std::string &path)
{
    // note: wrong mode errors are handled before dispatch to interface

    return m_node.has_path(path);
}

//-----------------------------------------------------------------------------
void
BasicHandle::close()
{
    if(m_open && !open_mode_read_only() )
    {
        // here is where it actually gets realized on disk
        io::save(m_node,
                 path(),
                 protocol(),
                 options());
        m_node.reset();
        m_open = false;
    }
}


//-----------------------------------------------------------------------------
// HDF5Handle Implementation
//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
#ifdef CONDUIT_RELAY_IO_HDF5_ENABLED
//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
HDF5Handle::HDF5Handle(const std::string &path,
                       const std::string &protocol,
                       const Node &options)
: HandleInterface(path,protocol,options),
  m_h5_id(-1)
{
    // empty
}
//-----------------------------------------------------------------------------
HDF5Handle::~HDF5Handle()
{
    close();
}

//-----------------------------------------------------------------------------
void
HDF5Handle::open()
{
    close();

    // call base class method, which does final sanity checks
    // and processes standard options (mode = "rw", etc)
    HandleInterface::open();

    if( utils::is_file( path() ) )
    {
        // check open mode to select proper hdf5 call

        if( open_mode_read_only() )
        {
            m_h5_id = hdf5_open_file_for_read( path() );
        } // support write with append
        else if ( open_mode_append() )
        {
            m_h5_id = hdf5_open_file_for_read_write( path() );
        } // support write with truncate
        else if ( open_mode_truncate() )
        {
            m_h5_id = hdf5_create_file( path() );
        }
    }
    else if(  open_mode_read_only() )
    {
        CONDUIT_ERROR("path: \""
                      << path()
                      << "\" does not exist, cannot open read only (mode = 'r')");
    }
    else
    {
        m_h5_id = hdf5_create_file( path() );
    }
}


//-----------------------------------------------------------------------------
bool
HDF5Handle::is_open() const
{
    return m_h5_id != -1;
}

//-----------------------------------------------------------------------------
void
HDF5Handle::read(Node &node)
{
    Node opts;
    read(node, opts);
}

//-----------------------------------------------------------------------------
void
HDF5Handle::read(Node &node,
                 const Node &opts)
{
    // note: wrong mode errors are handled before dispatch to interface

    hdf5_read(m_h5_id,opts,node);
}

//-----------------------------------------------------------------------------
void
HDF5Handle::read(const std::string &path,
                 Node &node)
{
    Node opts;
    read(path, node, opts);
}

//-----------------------------------------------------------------------------
void
HDF5Handle::read(const std::string &path,
                 Node &node,
                 const Node &opts)
{
    // note: wrong mode errors are handled before dispatch to interface

    hdf5_read(m_h5_id,path,opts,node);
}

//-----------------------------------------------------------------------------
void
HDF5Handle::write(const Node &node)
{
    Node opts;
    write(node, opts);
}

//-----------------------------------------------------------------------------
void
HDF5Handle::write(const Node &node,
                  const Node &opts)
{
    // note: wrong mode errors are handled before dispatch to interface

    // Options Push / Pop (only needed for write, since hdf5 only supports
    // write options
    Node prev_options;
    if(options().has_child("hdf5"))
    {
        hdf5_options(prev_options);
        hdf5_set_options(options()["hdf5"]);
    }

    hdf5_write(node,m_h5_id, opts);

    if(!prev_options.dtype().is_empty())
    {
        hdf5_set_options(prev_options);
    }
}


//-----------------------------------------------------------------------------
void
HDF5Handle::write(const Node &node,
                  const std::string &path)
{
    Node opts;
    write(node, path, opts);
}

//-----------------------------------------------------------------------------
void
HDF5Handle::write(const Node &node,
                  const std::string &path,
                  const Node &opts)
{
    // note: wrong mode errors are handled before dispatch to interface

    // Options Push / Pop (only needed for write, since hdf5 only supports
    // write options
    Node prev_options;
    if(options().has_child("hdf5"))
    {
        hdf5_options(prev_options);
        hdf5_set_options(options()["hdf5"]);
    }

    hdf5_write(node,m_h5_id,path,opts);

    if(!prev_options.dtype().is_empty())
    {
        hdf5_set_options(prev_options);
    }
}

//-----------------------------------------------------------------------------
void
HDF5Handle::list_child_names(std::vector<std::string> &res)
{
    // note: wrong mode errors are handled before dispatch to interface

    hdf5_group_list_child_names(m_h5_id, "/", res);
}

//-----------------------------------------------------------------------------
void
HDF5Handle::list_child_names(const std::string &path,
                             std::vector<std::string> &res)
{
    // note: wrong mode errors are handled before dispatch to interface

    hdf5_group_list_child_names(m_h5_id, path, res);
}

//-----------------------------------------------------------------------------
void
HDF5Handle::remove(const std::string &path)
{
    // note: wrong mode errors are handled before dispatch to interface

    hdf5_remove_path(m_h5_id,path);
}

//-----------------------------------------------------------------------------
bool
HDF5Handle::has_path(const std::string &path)
{
    // note: wrong mode errors are handled before dispatch to interface

    return hdf5_has_path(m_h5_id,path);
}


//-----------------------------------------------------------------------------
void
HDF5Handle::close()
{
    if(m_h5_id >= 0)
    {
        hdf5_close_file(m_h5_id);
    }
    m_h5_id = -1;
}

//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
#endif
//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------


//-----------------------------------------------------------------------------
// IOHandle Implementation
//-----------------------------------------------------------------------------

//-----------------------------------------------------------------------------
IOHandle::IOHandle()
: m_handle(NULL)
{

}

//-----------------------------------------------------------------------------
IOHandle::~IOHandle()
{
    close();
}

//-----------------------------------------------------------------------------
void
IOHandle::open(const std::string &path)
{
    close();
    m_handle = HandleInterface::create(path);
    if(m_handle != NULL)
    {
        m_handle->open();
    }
}

//-----------------------------------------------------------------------------
void
IOHandle::open(const std::string &path,
               const std::string &protocol)
{
    close();
    m_handle = HandleInterface::create(path, protocol);
    if(m_handle != NULL)
    {
        m_handle->open();
    }
}

//-----------------------------------------------------------------------------
void
IOHandle::open(const std::string &path,
               const Node &options)
{
    close();
    m_handle = HandleInterface::create(path, options);
    if(m_handle != NULL)
    {
        m_handle->open();
    }
}

//-----------------------------------------------------------------------------
void
IOHandle::open(const std::string &path,
               const std::string &protocol,
               const Node &options)
{
    close();
    m_handle = HandleInterface::create(path, protocol, options);
    if(m_handle != NULL)
    {
        m_handle->open();
    }
}

//-----------------------------------------------------------------------------
bool
IOHandle::is_open() const
{
    bool res = false;

    if(m_handle != NULL)
    {
        res = m_handle->is_open();
    }

    return res;
}

//-----------------------------------------------------------------------------
void
IOHandle::read(Node &node)
{
    Node opts;
    read(node,opts);
}

//-----------------------------------------------------------------------------
void
IOHandle::read(Node &node,
               const Node &opts)
{
    if(m_handle != NULL)
    {
        if( m_handle->open_mode_write_only() )
        {
            CONDUIT_ERROR("IOHandle: cannot read, handle is write only"
                          " (mode = '" << m_handle->open_mode() << "')");
        }

        m_handle->read(node,opts);
    }
    else
    {
        CONDUIT_ERROR("Invalid or closed handle.");
    }
}

//-----------------------------------------------------------------------------
void
IOHandle::read(const std::string &path,
               Node &node)
{
    Node opts;
    read(path,node,opts);
}

//-----------------------------------------------------------------------------
void
IOHandle::read(const std::string &path,
               Node &node,
               const Node &opts)
{
    if(m_handle != NULL)
    {
        if( m_handle->open_mode_write_only() )
        {
            CONDUIT_ERROR("IOHandle: cannot read, handle is write only"
                          " (mode = '" << m_handle->open_mode() << "')");
        }

        if(path.empty())
        {
            m_handle->read(node, opts);
        }
        else
        {
            m_handle->read(path, node, opts);
        }
    }
    else
    {
        CONDUIT_ERROR("Invalid or closed handle.");
    }
}

//-----------------------------------------------------------------------------
void
IOHandle::write(const Node &node)
{
    Node opts;
    write(node,opts);
}

//-----------------------------------------------------------------------------
void
IOHandle::write(const Node &node,
                const Node &opts)
{
    if(m_handle != NULL)
    {
        if( m_handle->open_mode_read_only() )
        {
            CONDUIT_ERROR("IOHandle: cannot write, handle is read only"
                          " (mode = '" << m_handle->open_mode() << "')");
        }

        m_handle->write(node, opts);
    }
    else
    {
        CONDUIT_ERROR("Invalid or closed handle.");
    }
}

//-----------------------------------------------------------------------------
void
IOHandle::write(const Node &node,
                const std::string &path)
{
    Node opts;
    write(node,path,opts);
}

//-----------------------------------------------------------------------------
void
IOHandle::write(const Node &node,
                const std::string &path,
                const Node &opts)
{
    if(m_handle != NULL)
    {
        if( m_handle->open_mode_read_only() )
        {
            CONDUIT_ERROR("IOHandle: cannot write, handle is read only"
                          " (mode = '" << m_handle->open_mode() << "')");
        }

        m_handle->write(node, path, opts);
    }
    else
    {
        CONDUIT_ERROR("Invalid or closed handle.");
    }

}

//-----------------------------------------------------------------------------
void
IOHandle::remove(const std::string &path)
{
    if(m_handle != NULL)
    {
         if( m_handle->open_mode_read_only() )
         {
             CONDUIT_ERROR("IOHandle: cannot remove path, handle is read only"
                           " (mode = '" << m_handle->open_mode() << "')");
         }

        m_handle->remove(path);
    }
    else
    {
        CONDUIT_ERROR("Invalid or closed handle.");
    }
}

//-----------------------------------------------------------------------------
void
IOHandle::list_child_names(std::vector<std::string> &names)
{
    names.clear();
    if(m_handle != NULL)
    {
         if( m_handle->open_mode_write_only() )
         {
             CONDUIT_ERROR("IOHandle: cannot list_child_names, handle is"
                           " write only"
                           " (mode = '" << m_handle->open_mode() << "')");
         }

        return m_handle->list_child_names(names);
    }
    else
    {
        CONDUIT_ERROR("Invalid or closed handle.");
    }
}


//-----------------------------------------------------------------------------
void
IOHandle::list_child_names(const std::string &path,
                           std::vector<std::string> &names)
{
    names.clear();
    if(m_handle != NULL)
    {
         if( m_handle->open_mode_write_only() )
         {
             CONDUIT_ERROR("IOHandle: cannot list_child_names, handle is"
                           " write only"
                           " (mode = '" << m_handle->open_mode() << "')");
         }

        return m_handle->list_child_names(path, names);
    }
    else
    {
        CONDUIT_ERROR("Invalid or closed handle.");
    }
}

//-----------------------------------------------------------------------------
bool
IOHandle::has_path(const std::string &path)
{
    if(m_handle != NULL)
    {
        if( m_handle->open_mode_write_only() )
        {
            CONDUIT_ERROR("IOHandle: cannot call has_path, handle is write"
                           " only"
                           " (mode = '" << m_handle->open_mode() << "')");
        }
        return m_handle->has_path(path);
    }
    else
    {
        CONDUIT_ERROR("Invalid or closed handle.");
    }

    return false;
}

//-----------------------------------------------------------------------------
void
IOHandle::close()
{
    if(m_handle != NULL)
    {
        m_handle->close();
        delete m_handle;
        m_handle = NULL;
    }
    // else, ignore ...
}


}
//-----------------------------------------------------------------------------
// -- end conduit::relay::<mpi>::io --
//-----------------------------------------------------------------------------

#ifdef CONDUIT_RELAY_IO_MPI_ENABLED
}
//-----------------------------------------------------------------------------
// -- begin conduit::relay::mpi --
//-----------------------------------------------------------------------------
#endif

}
//-----------------------------------------------------------------------------
// -- end conduit::relay --
//-----------------------------------------------------------------------------

}
//-----------------------------------------------------------------------------
// -- end conduit:: --
//-----------------------------------------------------------------------------