src/ShareContainer.h

   1 // -*- C++ -*-
   2
   3 #ifndef SHARECONTAINER_H
   4 #define SHARECONTAINER_H
   5
   6 #include <vector>
   7 #include <algorithm>
   8 #include <boost/utility.hpp>
   9 #include <boost/smart_ptr.hpp>
  10
  11 ///
  12 template<class Share>
  13 class ShareContainer : public noncopyable {
  14 public:
  15         ///
  16         typedef std::vector<boost::shared_ptr<Share> > Params;
  17         ///
  18         Params::value_type
  19         get(Share const & ps) const {
  20                 // First see if we already have this ps in the container
  21                 Params::iterator it = params.begin();
  22                 Params::iterator end = params.end();
  23                 for (; it != end; ++it) {
  24                         if (ps == *(*it).get())
  25                                 break;
  26                 }
  27                 Params::value_type tmp;
  28                 if (it == end) {
  29                         // ok we don't have it so we should
  30                         // insert it.
  31                         tmp.reset(new Share(ps));
  32                         params.push_back(tmp);
  33                         // We clean here. This can cause us to have
  34                         // some (one) unique elemements some times
  35                         // but we should gain a lot in speed.
  36                         clean();
  37                         std::sort(params.rbegin(), params.rend(), comp());
  38                 } else {
  39                         // yes we have it already
  40                         tmp = *it;
  41                 }
  42                 return tmp;
  43         }
  44 private:
  45         ///
  46         struct comp {
  47                 int operator()(Params::value_type const & p1,
  48                                Params::value_type const & p2) {
  49                         return p1.use_count() < p2.use_count();
  50                 }
  51         };
  52         ///
  53         struct isUnique {
  54                 bool operator()(Params::value_type const & p) const {
  55                         return p.unique();
  56                 }
  57         };
  58
  59         ///
  60         void clean() const {
  61                 // Remove all unique items. (i.e. entries that only
  62                 // exists in the conatainer and does not have a
  63                 // corresponding paragrah.
  64                 Params::iterator it = std::remove_if(params.begin(),
  65                                                      params.end(),
  66                                                      isUnique());
  67                 params.erase(it, params.end());
  68         }
  69
  70         ///
  71         mutable Params params;
  72 };
  73 #endif