Line data    Source code

       1             : 
       2             : /* Copyright (c) 2011-2017, Stefan Eilemann <eile@eyescale.ch>
       3             :  *
       4             :  * This file is part of Collage <https://github.com/Eyescale/Collage>
       5             :  *
       6             :  * This library is free software; you can redistribute it and/or modify it under
       7             :  * the terms of the GNU Lesser General Public License version 2.1 as published
       8             :  * by the Free Software Foundation.
       9             :  *
      10             :  * This library is distributed in the hope that it will be useful, but WITHOUT
      11             :  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
      12             :  * FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more
      13             :  * details.
      14             :  *
      15             :  * You should have received a copy of the GNU Lesser General Public License
      16             :  * along with this library; if not, write to the Free Software Foundation, Inc.,
      17             :  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
      18             :  */
      19             : 
      20             : #ifndef CO_CONNECTIONS_H
      21             : #define CO_CONNECTIONS_H
      22             : 
      23             : #include <co/connection.h>
      24             : #include <co/node.h>
      25             : #include <co/types.h>
      26             : 
      27             : #include <lunchbox/hash.h>
      28             : #include <set>
      29             : 
      30             : namespace co
      31             : {
      32             : /** @internal
      33             :  * Collect all connections of a set of nodes.
      34             :  *
      35             :  * Gives priority to multicast connections if a multicast connection is used
      36             :  * more than once. Connections are added to the result vector. Multicast
      37             :  * connections are added at most once. The result vector should be empty on
      38             :  * entry. The order of connections may not match the order of nodes.
      39             :  *
      40             :  * @param nodes the nodes to send to.
      41             :  * @param result the connection vector receiving new connections.
      42             :  */
      43         236 : inline Connections gatherConnections(const Nodes& nodes)
      44             : {
      45         236 :     Connections result;
      46             :     typedef std::unordered_map<
      47             :         ConstConnectionDescriptionPtr, NodePtr,
      48             :         lunchbox::hashRefPtr<const ConnectionDescription> >
      49             :         MCNodes;
      50         472 :     MCNodes mcNodes; // first node using a multicast connection
      51             : 
      52             :     typedef std::set<ConstConnectionDescriptionPtr> MCSet;
      53         472 :     MCSet mcSet; // multicast connection is added
      54             : 
      55         355 :     for (Nodes::const_iterator i = nodes.begin(); i != nodes.end(); ++i)
      56             :     {
      57         238 :         NodePtr node = *i;
      58         238 :         ConnectionPtr connection = node->getConnection(true /* preferMC */);
      59         119 :         LBASSERT(connection);
      60         119 :         if (!connection)
      61           0 :             continue;
      62             : 
      63         119 :         if (connection->isMulticast())
      64             :         {
      65           0 :             ConstConnectionDescriptionPtr desc = connection->getDescription();
      66           0 :             if (mcSet.find(desc) != mcSet.end()) // already added
      67           0 :                 continue;
      68             : 
      69           0 :             MCNodes::iterator j = mcNodes.find(desc);
      70           0 :             if (j == mcNodes.end())
      71             :             {
      72             :                 // first appearance of multicast connection
      73           0 :                 mcNodes[desc] = node;
      74           0 :                 continue;
      75             :             }
      76             : 
      77           0 :             mcSet.insert(desc); // mark as added
      78           0 :             mcNodes.erase(j);
      79             :         }
      80             : 
      81         119 :         result.push_back(connection);
      82             :     }
      83             : 
      84             :     // Add unicast connections for multicast node connections seen only once
      85         236 :     for (MCNodes::iterator i = mcNodes.begin(); i != mcNodes.end(); ++i)
      86             :     {
      87           0 :         ConnectionPtr connection = i->second->getConnection();
      88           0 :         LBASSERT(connection.isValid());
      89             : 
      90           0 :         if (connection.isValid())
      91           0 :             result.push_back(connection);
      92             :     }
      93         472 :     return result;
      94             : }
      95             : }
      96             : 
      97             : #endif // CO_CONNECTIONS_H