boost/property_map/parallel/local_property_map.hpp

   1 // Copyright (C) 2004-2006 The Trustees of Indiana University.
   2
   3 // Use, modification and distribution is subject to the Boost Software
   4 // License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
   5 // http://www.boost.org/LICENSE_1_0.txt)
   6
   7 //  Authors: Douglas Gregor
   8 //           Andrew Lumsdaine
   9
  10 // The placement of this #include probably looks very odd relative to
  11 // the #ifndef/#define pair below. However, this placement is
  12 // extremely important to allow the various property map headers to be
  13 // included in any order.
  14 #include <boost/property_map/property_map.hpp>
  15
  16 #ifndef BOOST_PARALLEL_LOCAL_PROPERTY_MAP_HPP
  17 #define BOOST_PARALLEL_LOCAL_PROPERTY_MAP_HPP
  18
  19 #ifndef BOOST_GRAPH_USE_MPI
  20 #error "Parallel BGL files should not be included unless <boost/graph/use_mpi.hpp> has been included"
  21 #endif
  22
  23 #include <cassert>
  24
  25 namespace boost {
  26   /** Property map that accesses an underlying, local property map
  27    * using a subset of the global keys.
  28    */
  29   template<typename ProcessGroup, typename GlobalMap, typename StorageMap>
  30   class local_property_map
  31   {
  32     typedef typename property_traits<GlobalMap>::value_type owner_local_pair;
  33
  34   public:
  35     typedef ProcessGroup                                   process_group_type;
  36     typedef typename property_traits<StorageMap>::value_type value_type;
  37     typedef typename property_traits<GlobalMap>::key_type key_type;
  38     typedef typename property_traits<StorageMap>::reference  reference;
  39     typedef typename property_traits<StorageMap>::category   category;
  40
  41     local_property_map() { }
  42
  43     local_property_map(const ProcessGroup& process_group,
  44                        const GlobalMap& global, const StorageMap& storage)
  45       : process_group_(process_group), global_(global), storage(storage) { }
  46
  47     reference operator[](const key_type& key)
  48     {
  49       owner_local_pair p = get(global_, key);
  50       assert(p.first == process_id(process_group_));
  51       return storage[p.second];
  52     }
  53
  54     GlobalMap& global() const { return global_; }
  55     StorageMap& base() const { return storage; }
  56
  57     ProcessGroup&       process_group()       { return process_group_; }
  58     const ProcessGroup& process_group() const { return process_group_; }
  59
  60   private:
  61     ProcessGroup process_group_;
  62     mutable GlobalMap global_;
  63     mutable StorageMap storage;
  64   };
  65
  66   template<typename ProcessGroup, typename GlobalMap, typename StorageMap>
  67   inline
  68   typename local_property_map<ProcessGroup, GlobalMap, StorageMap>::reference
  69   get(const local_property_map<ProcessGroup, GlobalMap, StorageMap>& pm,
  70       typename local_property_map<ProcessGroup, GlobalMap, StorageMap>::key_type
  71         const & key)
  72
  73   {
  74     typename property_traits<GlobalMap>::value_type p = get(pm.global(), key);
  75     return get(pm.base(), p.second);
  76   }
  77
  78   template<typename ProcessGroup, typename GlobalMap, typename StorageMap>
  79   inline void
  80   put(const local_property_map<ProcessGroup, GlobalMap, StorageMap>& pm,
  81       typename local_property_map<ProcessGroup, GlobalMap, StorageMap>
  82                  ::key_type const & key,
  83       typename local_property_map<ProcessGroup, GlobalMap, StorageMap>
  84                  ::value_type const& v)
  85   {
  86     typename property_traits<GlobalMap>::value_type p = get(pm.global(), key);
  87     assert(p.first == process_id(pm.process_group()));
  88     put(pm.base(), p.second, v);
  89   }
  90 } // end namespace boost
  91 #endif // BOOST_PARALLEL_LOCAL_PROPERTY_MAP_HPP