1 files changed, 139 insertions, 0 deletions
diff --git a/common/session/custom/session.hxx b/common/session/custom/session.hxx
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+++ b/common/session/custom/session.hxx
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+// file      : common/session/custom/session.hxx
+// copyright : Copyright (c) 2009-2012 Code Synthesis Tools CC
+// license   : GNU GPL v2; see accompanying LICENSE file
+
+#ifndef SESSION_HXX
+#define SESSION_HXX
+
+#include <map>
+#include <memory>
+#include <typeinfo>
+
+#include <odb/database.hxx>
+#include <odb/traits.hxx>            // odb::object_traits
+#include <odb/details/type-info.hxx> // odb::details::type_info_comparator
+
+// This custom session implementation assumes we are working with
+// one database at a time.
+//
+class session
+{
+public:
+  session ();
+  ~session ();
+
+private:
+  session (const session&);
+  session& operator= (const session&);
+
+  // Current session interface.
+  //
+public:
+  static bool
+  has_current ();
+
+  static session&
+  current ();
+
+  // Change tracking interface.
+  //
+  // Call flush() within a transaction to apply the changes to the
+  // database. Then after successfully committing the transaction,
+  // call mark() to mark all the changed objects as again unchanged.
+  //
+public:
+  void
+  flush (odb::database&);
+
+  void
+  mark ();
+
+private:
+  struct object_map_base
+  {
+    virtual
+    ~object_map_base () {}
+
+    virtual void
+    flush (odb::database&) = 0;
+
+    virtual void
+    mark () = 0;
+  };
+
+  template <typename T>
+  struct object_state
+  {
+    typedef typename odb::object_traits<T>::pointer_type pointer_type;
+
+    explicit
+    object_state (pointer_type o): obj (o), flushed_ (false) {}
+
+    pointer_type obj;
+    pointer_type orig;
+    bool flushed_;
+  };
+
+  template <typename T>
+  struct object_map: object_map_base,
+                     std::map<typename odb::object_traits<T>::id_type,
+                              object_state<T> >
+  {
+    virtual void
+    flush (odb::database&);
+
+    virtual void
+    mark ();
+  };
+
+  // Object cache interface.
+  //
+public:
+  template <typename T>
+  struct position
+  {
+    typedef object_map<T> map;
+    typedef typename map::iterator iterator;
+
+    position () {}
+    position (map& m, const iterator& p): map_ (&m), pos_ (p) {}
+
+    map* map_;
+    iterator pos_;
+  };
+
+  template <typename T>
+  position<T>
+  insert (odb::database&,
+          const typename odb::object_traits<T>::id_type&,
+          const typename odb::object_traits<T>::pointer_type&);
+
+  template <typename T>
+  static void
+  initialize (const position<T>&);
+
+  template <typename T>
+  typename odb::object_traits<T>::pointer_type
+  find (odb::database&, const typename odb::object_traits<T>::id_type&) const;
+
+  template <typename T>
+  void
+  erase (odb::database&, const typename odb::object_traits<T>::id_type&);
+
+  template <typename T>
+  static void
+  erase (const position<T>& p)
+  {
+    p.map_->erase (p.pos_);
+  }
+
+private:
+  typedef std::map<const std::type_info*,
+                   std::shared_ptr<object_map_base>,
+                   odb::details::type_info_comparator> type_map;
+  type_map map_;
+};
+
+#include "session.txx"
+
+#endif // SESSION_HXX