property_map/parallel/local_property_map.hpp

0001 // Copyright (C) 2004-2006 The Trustees of Indiana University.
0002
0003 // Use, modification and distribution is subject to the Boost Software
0004 // License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
0005 // http://www.boost.org/LICENSE_1_0.txt)
0006
0007 //  Authors: Douglas Gregor
0008 //           Andrew Lumsdaine
0009
0010 // The placement of this #include probably looks very odd relative to
0011 // the #ifndef/#define pair below. However, this placement is
0012 // extremely important to allow the various property map headers to be
0013 // included in any order.
0014 #include <boost/property_map/property_map.hpp>
0015
0016 #ifndef BOOST_PARALLEL_LOCAL_PROPERTY_MAP_HPP
0017 #define BOOST_PARALLEL_LOCAL_PROPERTY_MAP_HPP
0018
0019 #include <boost/assert.hpp>
0020
0021 namespace boost {
0022   /** Property map that accesses an underlying, local property map
0023    * using a subset of the global keys.
0024    */
0025   template<typename ProcessGroup, typename GlobalMap, typename StorageMap>
0026   class local_property_map
0027   {
0028     typedef typename property_traits<GlobalMap>::value_type owner_local_pair;
0029
0030   public:
0031     typedef ProcessGroup                                   process_group_type;
0032     typedef typename property_traits<StorageMap>::value_type value_type;
0033     typedef typename property_traits<GlobalMap>::key_type key_type;
0034     typedef typename property_traits<StorageMap>::reference  reference;
0035     typedef typename property_traits<StorageMap>::category   category;
0036
0037     local_property_map() { }
0038
0039     local_property_map(const ProcessGroup& process_group,
0040                        const GlobalMap& global, const StorageMap& storage)
0041       : process_group_(process_group), global_(global), storage(storage) { }
0042
0043     reference operator[](const key_type& key)
0044     {
0045       owner_local_pair p = get(global_, key);
0046       BOOST_ASSERT(p.first == process_id(process_group_));
0047       return storage[p.second];
0048     }
0049
0050     GlobalMap& global() const { return global_; }
0051     StorageMap& base() const { return storage; }
0052
0053     ProcessGroup&       process_group()       { return process_group_; }
0054     const ProcessGroup& process_group() const { return process_group_; }
0055
0056   private:
0057     ProcessGroup process_group_;
0058     mutable GlobalMap global_;
0059     mutable StorageMap storage;
0060   };
0061
0062   template<typename ProcessGroup, typename GlobalMap, typename StorageMap>
0063   inline
0064   typename local_property_map<ProcessGroup, GlobalMap, StorageMap>::reference
0065   get(const local_property_map<ProcessGroup, GlobalMap, StorageMap>& pm,
0066       typename local_property_map<ProcessGroup, GlobalMap, StorageMap>::key_type
0067         const & key)
0068
0069   {
0070     typename property_traits<GlobalMap>::value_type p = get(pm.global(), key);
0071     return get(pm.base(), p.second);
0072   }
0073
0074   template<typename ProcessGroup, typename GlobalMap, typename StorageMap>
0075   inline void
0076   put(const local_property_map<ProcessGroup, GlobalMap, StorageMap>& pm,
0077       typename local_property_map<ProcessGroup, GlobalMap, StorageMap>
0078                  ::key_type const & key,
0079       typename local_property_map<ProcessGroup, GlobalMap, StorageMap>
0080                  ::value_type const& v)
0081   {
0082     typename property_traits<GlobalMap>::value_type p = get(pm.global(), key);
0083     BOOST_ASSERT(p.first == process_id(pm.process_group()));
0084     put(pm.base(), p.second, v);
0085   }
0086 } // end namespace boost
0087 #endif // BOOST_PARALLEL_LOCAL_PROPERTY_MAP_HPP