libcore/MovieLibrary.h

   1 //
   2 //   Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Free Software
   3 //   Foundation, Inc
   4 //
   5 // This program is free software; you can redistribute it and/or modify
   6 // it under the terms of the GNU General Public License as published by
   7 // the Free Software Foundation; either version 3 of the License, or
   8 // (at your option) any later version.
   9 //
  10 // This program is distributed in the hope that it will be useful,
  11 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 // GNU General Public License for more details.
  14 //
  15 // You should have received a copy of the GNU General Public License
  16 // along with this program; if not, write to the Free Software
  17 // Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  18
  19 #ifndef GNASH_MOVIELIBRARY_H
  20 #define GNASH_MOVIELIBRARY_H
  21
  22 #include "rc.h"
  23 #include "movie_definition.h"
  24
  25 #include <boost/intrusive_ptr.hpp>
  26 #include <string>
  27 #include <map>
  28 #include <algorithm>
  29 #include <boost/thread/thread.hpp>
  30
  31 namespace gnash {
  32
  33 /// Library of SWF movies indexed by URL strings
  34 //
  35 /// Elements are actually movie_definitions, the ones
  36 /// associated with URLS. They may be BitmapMovieDefinitions or
  37 /// SWFMovieDefinitions.
  38 class MovieLibrary
  39 {
  40 public:
  41
  42     struct LibraryItem
  43     {
  44         boost::intrusive_ptr<movie_definition> def;
  45         unsigned hitCount;
  46     };
  47
  48     typedef std::map<std::string, LibraryItem> LibraryContainer;
  49
  50     MovieLibrary()
  51         :
  52         _limit(8)
  53     {
  54         RcInitFile& rcfile = RcInitFile::getDefaultInstance();
  55             setLimit(rcfile.getMovieLibraryLimit());
  56     }
  57
  58     /// Sets the maximum number of items to hold in the library. When adding new
  59     /// items, the one with the least hit count is being removed in that case.
  60     /// Zero is a valid limit (disables library).
  61     void setLimit(LibraryContainer::size_type limit)
  62     {
  63         _limit = limit;
  64         limitSize(_limit);
  65     }
  66
  67     bool get(const std::string& key,
  68             boost::intrusive_ptr<movie_definition>* ret)
  69     {
  70         boost::mutex::scoped_lock lock(_mapMutex);
  71         LibraryContainer::iterator it = _map.find(key);
  72         if (it == _map.end()) return false;
  73
  74         *ret = it->second.def;
  75         it->second.hitCount++;
  76         return true;
  77     }
  78
  79     void add(const std::string& key, movie_definition* mov)
  80     {
  81
  82         if (!_limit) return;
  83
  84         if (_limit) limitSize(_limit - 1);
  85
  86         LibraryItem temp;
  87
  88         temp.def = mov;
  89         temp.hitCount = 0;
  90
  91         boost::mutex::scoped_lock lock(_mapMutex);
  92         _map[key] = temp;
  93     }
  94
  95
  96     void clear()
  97     {
  98         boost::mutex::scoped_lock lock(_mapMutex);
  99         _map.clear();
 100     }
 101
 102 private:
 103
 104     static bool findWorstHitCount(const LibraryContainer::value_type& a,
 105                                 const LibraryContainer::value_type& b)
 106     {
 107         return (a.second.hitCount < b.second.hitCount);
 108     }
 109
 110     LibraryContainer _map;
 111     unsigned _limit;
 112
 113     void limitSize(LibraryContainer::size_type max) {
 114
 115         if (max < 1) {
 116             clear();
 117             return;
 118         }
 119
 120         while (_map.size() > max) {
 121             boost::mutex::scoped_lock lock(_mapMutex);
 122             _map.erase(std::min_element(_map.begin(), _map.end(),
 123                         &findWorstHitCount));
 124         }
 125
 126     }
 127
 128         mutable boost::mutex _mapMutex;
 129
 130 };
 131
 132 }
 133 #endif
 134
 135
 136 // Local Variables:
 137 // mode: C++
 138 // c-basic-offset: 8
 139 // tab-width: 8
 140 // indent-tabs-mode: t
 141 // End: