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         typedef typename Params::value_type value_type;
  19         ///
  20         value_type
  21         get(Share const & ps) const {
  22                 // First see if we already have this ps in the container
  23                 Params::iterator it = params.begin();
  24                 Params::iterator end = params.end();
  25                 for (; it != end; ++it) {
  26                         if (ps == *(*it).get())
  27                                 break;
  28                 }
  29                 value_type tmp;
  30                 if (it == end) {
  31                         // ok we don't have it so we should
  32                         // insert it.
  33                         tmp.reset(new Share(ps));
  34                         params.push_back(tmp);
  35                         // We clean here. This can cause us to have
  36                         // some (one) unique elemements some times
  37                         // but we should gain a lot in speed.
  38                         clean();
  39                         std::sort(params.rbegin(), params.rend(), comp());
  40                 } else {
  41                         // yes we have it already
  42                         tmp = *it;
  43                 }
  44                 return tmp;
  45         }
  46 private:
  47         ///
  48         struct comp {
  49                 int operator()(value_type const & p1,
  50                                value_type const & p2) {
  51                         return p1.use_count() < p2.use_count();
  52                 }
  53         };
  54         ///
  55         struct isUnique {
  56                 bool operator()(value_type const & p) const {
  57                         return p.unique();
  58                 }
  59         };
  60
  61         ///
  62         void clean() const {
  63                 // Remove all unique items. (i.e. entries that only
  64                 // exists in the conatainer and does not have a
  65                 // corresponding paragrah.
  66                 Params::iterator it = std::remove_if(params.begin(),
  67                                                      params.end(),
  68                                                      isUnique());
  69                 params.erase(it, params.end());
  70         }
  71
  72         ///
  73         mutable Params params;
  74 };
  75 #endif