ply_parser.h

/*
 * Software License Agreement (BSD License)
 *
 *  Point Cloud Library (PCL) - www.pointclouds.org
 *  Copyright (c) 2007-2012, Ares Lagae
 *  Copyright (c) 2010-2011, Willow Garage, Inc.
 *
 *  All rights reserved.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
 *
 *   * Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *   * Redistributions in binary form must reproduce the above
 *     copyright notice, this list of conditions and the following
 *     disclaimer in the documentation and/or other materials provided
 *     with the distribution.
 *   * Neither the name of the copyright holder(s) nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 *  FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 *  COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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 *  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 *  LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 *  ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 *  POSSIBILITY OF SUCH DAMAGE.
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 * $Id$
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 */
 
#pragma once
 
#include <pcl/io/ply/ply.h>
#include <pcl/io/ply/io_operators.h>
#include <pcl/pcl_macros.h>
 
#include <istream>
#include <memory>
#include <string>
#include <tuple>
#include <vector>
#include <functional>
#include <boost/lexical_cast.hpp> // for lexical_cast
#include <boost/mpl/fold.hpp> // for fold
#include <boost/mpl/inherit.hpp> // for inherit
#include <boost/mpl/inherit_linearly.hpp> // for inherit_linearly
#include <boost/mpl/joint_view.hpp> // for joint_view
#include <boost/mpl/transform.hpp> // for transform
#include <boost/mpl/vector.hpp> // for vector
 
namespace pcl
{
  namespace io
  {
    namespace ply
    {
      /** Class ply_parser parses a PLY file and generates appropriate atomic
        * parsers for the body.
        * \author Ares Lagae as part of libply, Nizar Sallem
        * Ported with agreement from the author under the terms of the BSD
        * license.
        */     
      class PCL_EXPORTS ply_parser
      {
        public:
 
          using info_callback_type = std::function<void (std::size_t, const std::string&)>;
          using warning_callback_type = std::function<void (std::size_t, const std::string&)>;
          using error_callback_type = std::function<void (std::size_t, const std::string&)>;
         
          using magic_callback_type = std::function<void ()>;
          using format_callback_type = std::function<void (format_type, const std::string&)>;
          using comment_callback_type = std::function<void (const std::string&)>;
          using obj_info_callback_type = std::function<void (const std::string&)>;
          using end_header_callback_type = std::function<bool ()>;
         
          using begin_element_callback_type = std::function<void ()>;
          using end_element_callback_type = std::function<void ()>;
          using element_callbacks_type = std::tuple<begin_element_callback_type, end_element_callback_type>;
          using element_definition_callback_type = std::function<element_callbacks_type (const std::string&, std::size_t)>;
         
          template <typename ScalarType>
          struct scalar_property_callback_type
          {
            using type = std::function<void (ScalarType)>;
          };
 
          template <typename ScalarType>
          struct scalar_property_definition_callback_type
          {
            using scalar_property_callback_type = typename scalar_property_callback_type<ScalarType>::type;
            using type = std::function<scalar_property_callback_type (const std::string&, const std::string&)>;
          };
       
          using scalar_types = boost::mpl::vector<int8, int16, int32, uint8, uint16, uint32, float32, float64>;
 
          class scalar_property_definition_callbacks_type
          {
            private:
              template <typename T>
              struct callbacks_element
              {
//                callbacks_element () : callback ();
                using scalar_type = T;
                typename scalar_property_definition_callback_type<scalar_type>::type callback;
              };
             
              using callbacks = boost::mpl::inherit_linearly<
                scalar_types,
                boost::mpl::inherit<
                boost::mpl::_1,
                callbacks_element<boost::mpl::_2>
                >
                >::type;
              callbacks callbacks_;
             
            public:
              template <typename ScalarType>
              const typename scalar_property_definition_callback_type<ScalarType>::type&
              get () const
              {
                return (static_cast<const callbacks_element<ScalarType>&> (callbacks_).callback);
              }
             
              template <typename ScalarType>
              typename scalar_property_definition_callback_type<ScalarType>::type&
              get ()
              {
                return (static_cast<callbacks_element<ScalarType>&> (callbacks_).callback);
              }
             
              template <typename ScalarType>
              friend typename scalar_property_definition_callback_type<ScalarType>::type&
              at (scalar_property_definition_callbacks_type& scalar_property_definition_callbacks);
           
              template <typename ScalarType>
              friend const typename scalar_property_definition_callback_type<ScalarType>::type&
              at (const scalar_property_definition_callbacks_type& scalar_property_definition_callbacks);
          };
 
          template <typename ScalarType> static
          typename scalar_property_definition_callback_type<ScalarType>::type&
          at (scalar_property_definition_callbacks_type& scalar_property_definition_callbacks)
          {
              return (scalar_property_definition_callbacks.get<ScalarType> ());
          }
 
          
          template <typename ScalarType> static
          const typename scalar_property_definition_callback_type<ScalarType>::type&
          at (const scalar_property_definition_callbacks_type& scalar_property_definition_callbacks)
          {
              return (scalar_property_definition_callbacks.get<ScalarType> ());
          }
 
          template <typename SizeType, typename ScalarType>
          struct list_property_begin_callback_type
          {
            using type = std::function<void (SizeType)>;
          };
         
          template <typename SizeType, typename ScalarType>
          struct list_property_element_callback_type
          {
            using type = std::function<void (ScalarType)>;
          };
       
          template <typename SizeType, typename ScalarType>
          struct list_property_end_callback_type
          {
            using type = std::function<void ()>;
          };
 
          template <typename SizeType, typename ScalarType>
          struct list_property_definition_callback_type
          {
            using list_property_begin_callback_type = typename list_property_begin_callback_type<SizeType, ScalarType>::type;
            using list_property_element_callback_type = typename list_property_element_callback_type<SizeType, ScalarType>::type;
            using list_property_end_callback_type = typename list_property_end_callback_type<SizeType, ScalarType>::type;
            using type = std::function<std::tuple<
              list_property_begin_callback_type,
              list_property_element_callback_type,
              list_property_end_callback_type
              > (const std::string&, const std::string&)>;
          };
 
          using size_types = boost::mpl::vector<uint8, uint16, uint32>;
     
          class list_property_definition_callbacks_type
          {
            private:
              template <typename T> struct pair_with : boost::mpl::pair<T,boost::mpl::_> {};
              template<typename Sequence1, typename Sequence2>
          
                struct sequence_product :
                  boost::mpl::fold<Sequence1, boost::mpl::vector0<>,
                    boost::mpl::joint_view<
                      boost::mpl::_1,boost::mpl::transform<Sequence2, pair_with<boost::mpl::_2> > > >
                {};
 
              template <typename T>
              struct callbacks_element
              {
                using size_type = typename T::first;
                using scalar_type = typename T::second;
                typename list_property_definition_callback_type<size_type, scalar_type>::type callback;
              };
           
              using callbacks = boost::mpl::inherit_linearly<sequence_product<size_types, scalar_types>::type, boost::mpl::inherit<boost::mpl::_1, callbacks_element<boost::mpl::_2> > >::type;
              callbacks callbacks_;
     
            public:
              template <typename SizeType, typename ScalarType>
              typename list_property_definition_callback_type<SizeType, ScalarType>::type&
              get ()
              {
                return (static_cast<callbacks_element<boost::mpl::pair<SizeType, ScalarType> >&> (callbacks_).callback);
              }
 
              template <typename SizeType, typename ScalarType>
              const typename list_property_definition_callback_type<SizeType, ScalarType>::type&
              get () const
              {
                return (static_cast<const callbacks_element<boost::mpl::pair<SizeType, ScalarType> >&> (callbacks_).callback);
              }
 
              template <typename SizeType, typename ScalarType>
              friend typename list_property_definition_callback_type<SizeType, ScalarType>::type&
              at (list_property_definition_callbacks_type& list_property_definition_callbacks);
           
              template <typename SizeType, typename ScalarType>
              friend const typename list_property_definition_callback_type<SizeType, ScalarType>::type&
              at (const list_property_definition_callbacks_type& list_property_definition_callbacks);
          };
          
          template <typename SizeType, typename ScalarType> static
          typename list_property_definition_callback_type<SizeType, ScalarType>::type&
          at (list_property_definition_callbacks_type& list_property_definition_callbacks)
          {
              return (list_property_definition_callbacks.get<SizeType, ScalarType> ());
          }
          
          template <typename SizeType, typename ScalarType> static
          const typename list_property_definition_callback_type<SizeType, ScalarType>::type&
          at (const list_property_definition_callbacks_type& list_property_definition_callbacks)
          {
              return (list_property_definition_callbacks.get<SizeType, ScalarType> ());
          }
 
 
          inline void
          info_callback (const info_callback_type& info_callback);
 
          inline void
          warning_callback (const warning_callback_type& warning_callback);
 
          inline void
          error_callback (const error_callback_type& error_callback);
 
          inline void
          magic_callback (const magic_callback_type& magic_callback);
 
          inline void
          format_callback (const format_callback_type& format_callback);
 
          inline void
          element_definition_callback (const element_definition_callback_type& element_definition_callback);
 
          inline void
          scalar_property_definition_callbacks (const scalar_property_definition_callbacks_type& scalar_property_definition_callbacks);
 
          inline void
          list_property_definition_callbacks (const list_property_definition_callbacks_type& list_property_definition_callbacks);
 
          inline void
          comment_callback (const comment_callback_type& comment_callback);
 
          inline void
          obj_info_callback (const obj_info_callback_type& obj_info_callback);
 
          inline void
          end_header_callback (const end_header_callback_type& end_header_callback);
 
          using flags_type = int;
          enum flags { };
 
          ply_parser () = default;
              
          bool parse (const std::string& filename);
          //inline bool parse (const std::string& filename);
 
        private:
            
          struct property
          {
            property (const std::string& name) : name (name) {}
            virtual ~property () = default;
            virtual bool parse (class ply_parser& ply_parser, format_type format, std::istream& istream) = 0;
            std::string name;
          };
            
          template <typename ScalarType>
          struct scalar_property : public property
          {
            using scalar_type = ScalarType;
            using callback_type = typename scalar_property_callback_type<scalar_type>::type;
            scalar_property (const std::string& name, callback_type callback)
              : property (name)
              , callback (callback)
            {}
            bool parse (class ply_parser& ply_parser, 
                        format_type format, 
                        std::istream& istream) override 
            { 
              return ply_parser.parse_scalar_property<scalar_type> (format, istream, callback); 
            }
            callback_type callback;
          };
 
          template <typename SizeType, typename ScalarType>
          struct list_property : public property
          {
            using size_type = SizeType;
            using scalar_type = ScalarType;
            using begin_callback_type = typename list_property_begin_callback_type<size_type, scalar_type>::type;
            using element_callback_type = typename list_property_element_callback_type<size_type, scalar_type>::type;
            using end_callback_type = typename list_property_end_callback_type<size_type, scalar_type>::type;
            list_property (const std::string& name, 
                           begin_callback_type begin_callback, 
                           element_callback_type element_callback, 
                           end_callback_type end_callback)
              : property (name)
              , begin_callback (begin_callback)
              , element_callback (element_callback)
              , end_callback (end_callback)
            {}
            bool parse (class ply_parser& ply_parser, 
                        format_type format, 
                        std::istream& istream) override 
            { 
              return ply_parser.parse_list_property<size_type, scalar_type> (format, 
                                                                             istream,
                                                                             begin_callback,
                                                                             element_callback,
                                                                             end_callback);
            }
            begin_callback_type begin_callback;
            element_callback_type element_callback;
            end_callback_type end_callback;
          };
        
          struct element
          {
            element (const std::string& name, 
                    std::size_t count, 
                    const begin_element_callback_type& begin_element_callback, 
                    const end_element_callback_type& end_element_callback)
              : name (name)
              , count (count)
              , begin_element_callback (begin_element_callback)
              , end_element_callback (end_element_callback)
            {}
            std::string name;
            std::size_t count;
            begin_element_callback_type begin_element_callback;
            end_element_callback_type end_element_callback;
            std::vector<std::shared_ptr<property>> properties;
          };
          
          info_callback_type info_callback_ = [](std::size_t, const std::string&){};
          warning_callback_type warning_callback_ = [](std::size_t, const std::string&){};
          error_callback_type error_callback_ = [](std::size_t, const std::string&){};
          
          magic_callback_type magic_callback_ = [](){};
          format_callback_type format_callback_ = [](format_type, const std::string&){};
          comment_callback_type comment_callback_ = [](const std::string&){};
          obj_info_callback_type obj_info_callback_ = [](const std::string&){};
          end_header_callback_type end_header_callback_ = [](){return true;};
 
          element_definition_callback_type element_definition_callbacks_ = 
              [](const std::string&, std::size_t)
              {
                  return std::make_tuple([](){}, [](){});
              };
          scalar_property_definition_callbacks_type scalar_property_definition_callbacks_;
          list_property_definition_callbacks_type list_property_definition_callbacks_;
          
          template <typename ScalarType> inline void 
          parse_scalar_property_definition (const std::string& property_name);
 
          template <typename SizeType, typename ScalarType> inline void 
          parse_list_property_definition (const std::string& property_name);
          
          template <typename ScalarType> inline bool 
          parse_scalar_property (format_type format, 
                                 std::istream& istream, 
                                 const typename scalar_property_callback_type<ScalarType>::type& scalar_property_callback);
 
          template <typename SizeType, typename ScalarType> inline bool 
          parse_list_property (format_type format, 
                               std::istream& istream, 
                               const typename list_property_begin_callback_type<SizeType, ScalarType>::type& list_property_begin_callback, 
                               const typename list_property_element_callback_type<SizeType, ScalarType>::type& list_property_element_callback, 
                               const typename list_property_end_callback_type<SizeType, ScalarType>::type& list_property_end_callback);
            
          std::size_t line_number_{0};
          element* current_element_{nullptr};
      };
    } // namespace ply
  } // namespace io
} // namespace pcl
 
/* inline bool pcl::io::ply::ply_parser::parse (const std::string& filename) */
/* { */
/*   std::ifstream ifstream (filename.c_str ()); */
/*   return (parse (ifstream)); */
/* } */
 
inline void pcl::io::ply::ply_parser::info_callback (const info_callback_type& info_callback)
{
  info_callback_ = info_callback;
}
    
inline void pcl::io::ply::ply_parser::warning_callback (const warning_callback_type& warning_callback)
{
  warning_callback_ = warning_callback;
}
    
inline void pcl::io::ply::ply_parser::error_callback (const error_callback_type& error_callback)
{
  error_callback_ = error_callback;
}
    
inline void pcl::io::ply::ply_parser::magic_callback (const magic_callback_type& magic_callback)
{
  magic_callback_ = magic_callback;
}
    
inline void pcl::io::ply::ply_parser::format_callback (const format_callback_type& format_callback)
{
  format_callback_ = format_callback;
}
    
inline void pcl::io::ply::ply_parser::element_definition_callback (const element_definition_callback_type& element_definition_callback)
{
  element_definition_callbacks_ = element_definition_callback;
}
    
inline void pcl::io::ply::ply_parser::scalar_property_definition_callbacks (const scalar_property_definition_callbacks_type& scalar_property_definition_callbacks)
{
  scalar_property_definition_callbacks_ = scalar_property_definition_callbacks;
}
    
inline void pcl::io::ply::ply_parser::list_property_definition_callbacks (const list_property_definition_callbacks_type& list_property_definition_callbacks)
{
  list_property_definition_callbacks_ = list_property_definition_callbacks;
}
    
inline void pcl::io::ply::ply_parser::comment_callback (const comment_callback_type& comment_callback)
{
  comment_callback_ = comment_callback;
}
 
inline void pcl::io::ply::ply_parser::obj_info_callback (const obj_info_callback_type& obj_info_callback)
{
  obj_info_callback_ = obj_info_callback;
}
 
inline void pcl::io::ply::ply_parser::end_header_callback (const end_header_callback_type& end_header_callback)
{
  end_header_callback_ = end_header_callback;
}
 
template <typename ScalarType>
inline void pcl::io::ply::ply_parser::parse_scalar_property_definition (const std::string& property_name)
{
  using scalar_type = ScalarType;
  typename scalar_property_definition_callback_type<scalar_type>::type& scalar_property_definition_callback = 
    scalar_property_definition_callbacks_.get<scalar_type> ();
  typename scalar_property_callback_type<scalar_type>::type scalar_property_callback;
  if (scalar_property_definition_callback)
  {
    scalar_property_callback = scalar_property_definition_callback (current_element_->name, property_name);
  }
  if (!scalar_property_callback)
  {
    if (warning_callback_)
    {
      warning_callback_ (line_number_, 
                        "property '" + std::string (type_traits<scalar_type>::name ()) + " " + 
                        property_name + "' of element '" + current_element_->name + "' is not handled");
    }
  }
  current_element_->properties.emplace_back (new scalar_property<scalar_type> (property_name, scalar_property_callback));
}
 
template <typename SizeType, typename ScalarType>
inline void pcl::io::ply::ply_parser::parse_list_property_definition (const std::string& property_name)
{
  using size_type = SizeType;
  using scalar_type = ScalarType;
  using list_property_definition_callback_type = typename  list_property_definition_callback_type<size_type, scalar_type>::type;
  list_property_definition_callback_type& list_property_definition_callback = list_property_definition_callbacks_.get<size_type, scalar_type> ();
  using list_property_begin_callback_type = typename list_property_begin_callback_type<size_type, scalar_type>::type;
  using list_property_element_callback_type = typename list_property_element_callback_type<size_type, scalar_type>::type;
  using list_property_end_callback_type = typename list_property_end_callback_type<size_type, scalar_type>::type;
  std::tuple<list_property_begin_callback_type, list_property_element_callback_type, list_property_end_callback_type> list_property_callbacks;
  if (list_property_definition_callback)
  {
    list_property_callbacks = list_property_definition_callback (current_element_->name, property_name);
  }
  if (!std::get<0> (list_property_callbacks) || !std::get<1> (list_property_callbacks) || !std::get<2> (list_property_callbacks))
  {
    if (warning_callback_)
    {
      warning_callback_ (line_number_, 
                        "property 'list " + std::string (type_traits<size_type>::name ()) + " " + 
                        std::string (type_traits<scalar_type>::name ()) + " " + 
                        property_name + "' of element '" + 
                        current_element_->name + "' is not handled");
    }
  }
  current_element_->properties.emplace_back (new list_property<size_type, scalar_type> (
                                             property_name, 
                                             std::get<0> (list_property_callbacks), 
                                             std::get<1> (list_property_callbacks), 
                                             std::get<2> (list_property_callbacks)));
}
 
template <typename ScalarType>
inline bool pcl::io::ply::ply_parser::parse_scalar_property (format_type format, 
                                                             std::istream& istream, 
                                                             const typename scalar_property_callback_type<ScalarType>::type& scalar_property_callback)
{
  using namespace io_operators;
  using scalar_type = ScalarType;
  if (format == ascii_format)
  {
    std::string value_s;
    scalar_type value;
    char space = ' ';
    istream >> value_s;
    try
    {
      value = static_cast<scalar_type> (boost::lexical_cast<typename pcl::io::ply::type_traits<scalar_type>::parse_type> (value_s));
    }
    catch (boost::bad_lexical_cast &)
    {
      value = std::numeric_limits<scalar_type>::quiet_NaN ();
    }
 
    if (!istream.eof ())
      istream >> space >> std::ws;
    if (!istream || !isspace (space))
    {
      if (error_callback_)
        error_callback_ (line_number_, "error while parsing scalar property (file format: ascii)");
      return (false);
    }
    if (scalar_property_callback)
      scalar_property_callback (value);
    return (true);
  }
  scalar_type value = std::numeric_limits<scalar_type>::quiet_NaN ();
  istream.read (reinterpret_cast<char*> (&value), sizeof (scalar_type));
  if (!istream)
  {
    if (error_callback_)
      error_callback_ (line_number_, "error while parsing scalar property (file format: binary)");
    return (false);
  }
  if (((format == binary_big_endian_format) && (host_byte_order == little_endian_byte_order)) ||
      ((format == binary_little_endian_format) && (host_byte_order == big_endian_byte_order)))
    swap_byte_order (value);
  if (scalar_property_callback)
    scalar_property_callback (value);
  return (true);
}
 
template <typename SizeType, typename ScalarType>
inline bool pcl::io::ply::ply_parser::parse_list_property (format_type format, std::istream& istream, 
                                                           const typename list_property_begin_callback_type<SizeType, ScalarType>::type& list_property_begin_callback, 
                                                           const typename list_property_element_callback_type<SizeType, ScalarType>::type& list_property_element_callback, 
                                                           const typename list_property_end_callback_type<SizeType, ScalarType>::type& list_property_end_callback)
{
  using namespace io_operators;
  using size_type = SizeType;
  using scalar_type = ScalarType;
  if (format == ascii_format)
  {
    size_type size = std::numeric_limits<size_type>::infinity ();
    char space = ' ';
    istream >> size;
    if (!istream.eof ())
    {
      istream >> space >> std::ws;
    }
    if (!istream || !isspace (space))
    {
      if (error_callback_)
      {
        error_callback_ (line_number_, "error while parsing list (file format: ascii)");
      }
      return (false);
    }
    if (list_property_begin_callback)
    {
      list_property_begin_callback (size);
    }
    for (std::size_t index = 0; index < size; ++index)
    {
      std::string value_s;
      scalar_type value;
      char space = ' ';
      istream >> value_s;
      try
      {
        value = static_cast<scalar_type> (boost::lexical_cast<typename pcl::io::ply::type_traits<scalar_type>::parse_type> (value_s));
      }
      catch (boost::bad_lexical_cast &)
      {
        value = std::numeric_limits<scalar_type>::quiet_NaN ();
      }
 
      if (!istream.eof ())
      {
        istream >> space >> std::ws;
      }
      if (!istream || !isspace (space))
      {
        if (error_callback_)
        {
          error_callback_ (line_number_, "error while parsing list (file format: ascii)");
        }
        return (false);
      }
      if (list_property_element_callback)
      {
        list_property_element_callback (value);
      }
    }
    if (list_property_end_callback)
    {
      list_property_end_callback ();
    }
    return (true);
  }
  size_type size = std::numeric_limits<size_type>::infinity ();
  istream.read (reinterpret_cast<char*> (&size), sizeof (size_type));
  if (((format == binary_big_endian_format) && (host_byte_order == little_endian_byte_order)) || 
      ((format == binary_little_endian_format) && (host_byte_order == big_endian_byte_order)))
  {
    swap_byte_order (size);
  }
  if (!istream)
  {
    if (error_callback_)
    {
      error_callback_ (line_number_, "error while parsing list (file format: binary)");
    }
    return (false);
  }
  if (list_property_begin_callback)
  {
    list_property_begin_callback (size);
  }
  for (std::size_t index = 0; index < size; ++index) {
    scalar_type value  = std::numeric_limits<scalar_type>::quiet_NaN ();
    istream.read (reinterpret_cast<char*> (&value), sizeof (scalar_type));
    if (!istream) {
      if (error_callback_) {
        error_callback_ (line_number_, "error while parsing list (file format: binary)");
      }
      return (false);
    }
    if (((format == binary_big_endian_format) && (host_byte_order == little_endian_byte_order)) ||
        ((format == binary_little_endian_format) && (host_byte_order == big_endian_byte_order)))
    {
      swap_byte_order (value);
    }
    if (list_property_element_callback)
    {
      list_property_element_callback (value);
    }
  }
  if (list_property_end_callback)
  {
    list_property_end_callback ();
  }
  return (true);
}