Add support for maintaining log of database model changes

7 files changed, 126 insertions, 13 deletions

diff --git a/odb/semantics/relational/changelog.cxx b/odb/semantics/relational/changelog.cxx
index 05dd529..cd94494 100644
--- a/odb/semantics/relational/changelog.cxx
+++ b/odb/semantics/relational/changelog.cxx
@@ -73,6 +73,7 @@ namespace semantics
            i != contains_changeset_.rend (); ++i)
       {
         (*i)->changeset ().serialize (s);
+        s.characters ("\n");
       }
 
       model ().serialize (s);
diff --git a/odb/semantics/relational/elements.cxx b/odb/semantics/relational/elements.cxx
index 43c03c0..e14bc00 100644
--- a/odb/semantics/relational/elements.cxx
+++ b/odb/semantics/relational/elements.cxx
@@ -70,6 +70,24 @@ namespace semantics
         throw duplicate_name (*this, (*i->second)->nameable (), n);
     }
 
+    template <>
+    void scope<uname>::
+    remove_edge_left (names_type& e)
+    {
+      typename names_iterator_map::iterator i (iterator_map_.find (&e));
+      assert (i != iterator_map_.end ());
+
+      // If we are removing the first key, then move to the next key (or
+      // the end which means there are no keys).
+      //
+      if (first_key_ == i->second)
+        first_key_++;
+
+      names_.erase (i->second);
+      names_map_.erase (e.name ());
+      iterator_map_.erase (i);
+    }
+
     // type info
     //
     namespace
diff --git a/odb/semantics/relational/elements.hxx b/odb/semantics/relational/elements.hxx
index 2321e1a..381d7a8 100644
--- a/odb/semantics/relational/elements.hxx
+++ b/odb/semantics/relational/elements.hxx
@@ -149,6 +149,20 @@ namespace semantics
         nameable_ = &n;
       }
 
+      void
+      clear_left_node (scope_type& n)
+      {
+        assert (scope_ == &n);
+        scope_ = 0;
+      }
+
+      void
+      clear_right_node (nameable_type& n)
+      {
+        assert (nameable_ == &n);
+        nameable_ = 0;
+      }
+
     protected:
       name_type name_;
       scope_type* scope_;
@@ -169,22 +183,16 @@ namespace semantics
       typedef relational::scope<N> scope_type;
 
       name_type const&
-      name () const
-      {
-        return named_->name ();
-      }
+      name () const {return named_->name ();}
 
       scope_type&
-      scope () const
-      {
-        return named ().scope ();
-      }
+      scope () const {return named ().scope ();}
 
       names_type&
-      named () const
-      {
-        return *named_;
-      }
+      named () const {return *named_;}
+
+      string const&
+      id () const {return id_;}
 
     public:
       // Id identifies the C++ node (e.g., a class or a data member) that
@@ -208,6 +216,13 @@ namespace semantics
         named_ = &e;
       }
 
+      virtual void
+      remove_edge_right (names_type& e)
+      {
+        assert (named_ == &e);
+        named_ = 0;
+      }
+
       using node::add_edge_right;
 
     protected:
@@ -298,6 +313,12 @@ namespace semantics
         return names_.end ();
       }
 
+      bool
+      names_empty () const
+      {
+        return names_.empty ();
+      }
+
       // Find.
       //
       template <typename T>
@@ -324,6 +345,9 @@ namespace semantics
       virtual void
       add_edge_left (names_type&);
 
+      virtual void
+      remove_edge_left (names_type&);
+
     protected:
       scope (scope const&, graph&);
       scope (xml::parser&, graph&);
@@ -343,6 +367,10 @@ namespace semantics
     void scope<uname>::
     add_edge_left (names_type&);
 
+    template <>
+    void scope<uname>::
+    remove_edge_left (names_type&);
+
     typedef scope<uname> uscope;
     typedef scope<qname> qscope;
   }
diff --git a/odb/semantics/relational/elements.txx b/odb/semantics/relational/elements.txx
index 53946a0..e1fd6d5 100644
--- a/odb/semantics/relational/elements.txx
+++ b/odb/semantics/relational/elements.txx
@@ -169,5 +169,17 @@ namespace semantics
       else
         throw duplicate_name (*this, (*i->second)->nameable (), e.nameable ());
     }
+
+    template <typename N>
+    void scope<N>::
+    remove_edge_left (names_type& e)
+    {
+      typename names_iterator_map::iterator i (iterator_map_.find (&e));
+      assert (i != iterator_map_.end ());
+
+      names_.erase (i->second);
+      names_map_.erase (e.name ());
+      iterator_map_.erase (i);
+    }
   }
 }
diff --git a/odb/semantics/relational/model.hxx b/odb/semantics/relational/model.hxx
index 626befd..575100f 100644
--- a/odb/semantics/relational/model.hxx
+++ b/odb/semantics/relational/model.hxx
@@ -19,6 +19,9 @@ namespace semantics
       version_type
       version () const {return version_;}
 
+      void
+      version (version_type v) {version_ = v;}
+
     public:
       model (version_type v): version_ (v) {}
       model (model const&, graph&);
diff --git a/odb/semantics/relational/table.cxx b/odb/semantics/relational/table.cxx
index 1c6e784..6d1c3a2 100644
--- a/odb/semantics/relational/table.cxx
+++ b/odb/semantics/relational/table.cxx
@@ -13,7 +13,7 @@ namespace semantics
     // table
     //
     table::
-    table (table const& t, qscope& s, graph& g)
+    table (table const& t, qscope&, graph& g)
         : qnameable (t, g), uscope (t, g)
     {
     }
@@ -56,6 +56,29 @@ namespace semantics
       s.end_element ();
     }
 
+    // drop_table
+    //
+    drop_table::
+    drop_table (xml::parser& p, qscope&, graph& g)
+        : qnameable (p, g)
+    {
+      p.content (xml::parser::empty);
+    }
+
+    drop_table& drop_table::
+    clone (qscope& s, graph& g) const
+    {
+      return g.new_node<drop_table> (*this, s, g);
+    }
+
+    void drop_table::
+    serialize (xml::serializer& s) const
+    {
+      s.start_element (xmlns, "drop-table");
+      qnameable::serialize_attributes (s);
+      s.end_element ();
+    }
+
     // type info
     //
     namespace
@@ -67,6 +90,8 @@ namespace semantics
           qnameable::parser_map_["table"] = &qnameable::parser_impl<table>;
           qnameable::parser_map_["add-table"] =
             &qnameable::parser_impl<add_table>;
+          qnameable::parser_map_["drop-table"] =
+            &qnameable::parser_impl<drop_table>;
 
           using compiler::type_info;
 
@@ -86,6 +111,14 @@ namespace semantics
             ti.add_base (typeid (table));
             insert (ti);
           }
+
+          // drop_table
+          //
+          {
+            type_info ti (typeid (drop_table));
+            ti.add_base (typeid (qnameable));
+            insert (ti);
+          }
         }
       } init_;
     }
diff --git a/odb/semantics/relational/table.hxx b/odb/semantics/relational/table.hxx
index 768d3d7..3eb1b73 100644
--- a/odb/semantics/relational/table.hxx
+++ b/odb/semantics/relational/table.hxx
@@ -48,6 +48,24 @@ namespace semantics
       virtual void
       serialize (xml::serializer&) const;
     };
+
+    class drop_table: public qnameable
+    {
+    public:
+      drop_table (string const& id): qnameable (id) {}
+      drop_table (drop_table const& t, qscope&, graph& g): qnameable (t, g) {}
+      drop_table (xml::parser&, qscope&, graph&);
+
+      virtual drop_table&
+      clone (qscope&, graph&) const;
+
+      virtual string
+      kind () const {return "drop table";}
+
+      virtual void
+      serialize (xml::serializer&) const;
+    };
+
   }
 }