Small refactoring, added persisted flag for meta info

src/db/db/dbLayout.cc

@@ -1753,7 +1753,7 @@ Layout::do_update ()
   delete pr;
 }
 
-static Layout::meta_info s_empty_meta;
+static Layout::meta_info_map s_empty_meta;
 
 Layout::meta_info_iterator
 Layout::begin_meta (db::cell_index_type ci) const
@@ -1823,12 +1823,12 @@ Layout::remove_meta_info (meta_info_name_id_type name_id)
   m_meta_info.erase (name_id);
 }
 
-const tl::Variant &
+const MetaInfo &
-Layout::meta_info_value (meta_info_name_id_type name_id) const
+Layout::meta_info (meta_info_name_id_type name_id) const
 {
   auto n = m_meta_info.find (name_id);
-  static tl::Variant null_value;
+  static MetaInfo null_value;
-  return n != m_meta_info.end () ? n->second.value : null_value;
+  return n != m_meta_info.end () ? n->second : null_value;
 }
 
 void
@@ -1852,18 +1852,18 @@ Layout::remove_meta_info (db::cell_index_type ci, meta_info_name_id_type name_id
   }
 }
 
-const tl::Variant &
+const MetaInfo &
-Layout::meta_info_value (db::cell_index_type ci, meta_info_name_id_type name_id) const
+Layout::meta_info (db::cell_index_type ci, meta_info_name_id_type name_id) const
 {
   auto c = m_meta_info_by_cell.find (ci);
   if (c != m_meta_info_by_cell.end ()) {
     auto i = c->second.find (name_id);
     if (i != c->second.end ()) {
-      return i->second.value;
+      return i->second;
     }
   }
 
-  static tl::Variant null_value;
+  static MetaInfo null_value;
   return null_value;
 }
 

src/db/db/dbLayout.h

@@ -466,8 +466,8 @@ public:
   typedef std::map<std::pair<lib_id_type, cell_index_type>, cell_index_type> lib_proxy_map;
   typedef LayerIterator layer_iterator;
   typedef size_t meta_info_name_id_type;
-  typedef std::map<meta_info_name_id_type, MetaInfo> meta_info;
+  typedef std::map<meta_info_name_id_type, MetaInfo> meta_info_map;
-  typedef meta_info::const_iterator meta_info_iterator;
+  typedef meta_info_map::const_iterator meta_info_iterator;
 
   /**
    *  @brief A helper functor to compare "const char *" by the content
@@ -1876,15 +1876,15 @@ public:
    *  @brief Gets the meta info value for a meta info object with the given name
    *  If no object with that name exists, an empty string is returned
    */
-  const tl::Variant &meta_info_value (const std::string &name) const
+  const MetaInfo &meta_info (const std::string &name) const
   {
-    return meta_info_value (meta_info_name_id (name));
+    return meta_info (meta_info_name_id (name));
   }
 
   /**
    *  @brief Gets the meta info value for a meta info object with the given name ID
    */
-  const tl::Variant &meta_info_value (meta_info_name_id_type name_id) const;
+  const MetaInfo &meta_info (meta_info_name_id_type name_id) const;
 
   /**
    *  @brief Clears the meta information for a specific cell
@@ -1927,16 +1927,16 @@ public:
    *  @brief Gets the meta info value for a meta info object with the given name for the given cell
    *  If no object with that name exists, an empty string is returned
    */
-  const tl::Variant &meta_info_value (db::cell_index_type ci, const std::string &name) const
+  const MetaInfo &meta_info (db::cell_index_type ci, const std::string &name) const
   {
-    return meta_info_value (ci, meta_info_name_id (name));
+    return meta_info (ci, meta_info_name_id (name));
   }
 
   /**
    *  @brief Gets the meta info value for a meta info object with the given name ID for the given cell
    *  If no object with that name exists, an empty string is returned
    */
-  const tl::Variant &meta_info_value (db::cell_index_type ci, meta_info_name_id_type name_id) const;
+  const MetaInfo &meta_info (db::cell_index_type ci, meta_info_name_id_type name_id) const;
 
   /**
    *  @brief This event is triggered when the technology changes
@@ -1980,8 +1980,8 @@ private:
   bool m_editable;
   std::map<std::string, meta_info_name_id_type> m_meta_info_name_map;
   std::vector<std::string> m_meta_info_names;
-  meta_info m_meta_info;
+  meta_info_map m_meta_info;
-  std::map<db::cell_index_type, meta_info> m_meta_info_by_cell;
+  std::map<db::cell_index_type, meta_info_map> m_meta_info_by_cell;
 
   std::string m_tech_name;
   tl::Mutex m_lock;

src/db/db/dbMetaInfo.h

@@ -41,19 +41,21 @@ namespace db
  */
 struct DB_PUBLIC MetaInfo
 {
-  MetaInfo (const std::string &d, const tl::Variant &v)
+  MetaInfo (const std::string &d, const tl::Variant &v, bool p = false)
-    : description (d), value (v)
+    : description (d), value (v), persisted (p)
   {
     //  .. nothing else ..
   }
 
   MetaInfo ()
+    : persisted (false)
   {
     //  .. nothing else ..
   }
 
   std::string description;
   tl::Variant value;
+  bool persisted;
 };
 
 /**

src/db/db/gsiDeclDbCell.cc

@@ -1010,7 +1010,18 @@ static const tl::Variant &cell_meta_info_value (db::Cell *cell, const std::strin
     static tl::Variant null_value;
     return null_value;
   } else {
-    return cell->layout ()->meta_info_value (cell->cell_index (), name);
+    return cell->layout ()->meta_info (cell->cell_index (), name).value;
+  }
+}
+
+static MetaInfo cell_meta_info (db::Cell *cell, const std::string &name)
+{
+  if (! cell->layout ()) {
+    static MetaInfo null_value;
+    return null_value;
+  } else {
+    const db::MetaInfo &value = cell->layout ()->meta_info (cell->cell_index (), name);
+    return MetaInfo (name, value);
   }
 }
 
@@ -1841,7 +1852,16 @@ Class<db::Cell> decl_Cell ("db", "Cell",
     "@brief Gets the meta information value for a given name\n"
     "See \\LayoutMetaInfo for details about cells and meta information.\n"
     "\n"
-    "If no meta information with the given name exists, an nil value will be returned.\n"
+    "If no meta information with the given name exists, a nil value will be returned.\n"
+    "A more generic version that delivers all fields of the meta information is \\meta_info.\n"
+    "\n"
+    "This method has been introduced in version 0.28.7."
+  ) +
+  gsi::method_ext ("meta_info", &cell_meta_info, gsi::arg ("name"),
+    "@brief Gets the meta information for a given name\n"
+    "See \\LayoutMetaInfo for details about cells and meta information.\n"
+    "\n"
+    "If no meta information with the given name exists, a default object with empty fields will be returned.\n"
     "\n"
     "This method has been introduced in version 0.28.7."
   ) +

src/db/db/gsiDeclDbLayout.cc

@@ -908,6 +908,18 @@ static void layout_add_meta_info (db::Layout *layout, const MetaInfo &mi)
   layout->add_meta_info (mi.name, db::MetaInfo (mi.description, mi.value));
 }
 
+static MetaInfo layout_get_meta_info (db::Layout *layout, const std::string &name)
+{
+  const db::MetaInfo &value = layout->meta_info (name);
+  return MetaInfo (name, value);
+}
+
+static const tl::Variant &layout_get_meta_info_value (db::Layout *layout, const std::string &name)
+{
+  const db::MetaInfo &value = layout->meta_info (name);
+  return value.value;
+}
+
 static MetaInfoIterator layout_each_meta_info (const db::Layout *layout)
 {
   return MetaInfoIterator (layout, layout->begin_meta (), layout->end_meta ());
@@ -1052,14 +1064,23 @@ Class<db::Layout> decl_Layout ("db", "Layout",
     "\n"
     "This method has been introduced in version 0.25."
   ) +
-  gsi::method ("meta_info_value", static_cast<const tl::Variant &(db::Layout::*) (const std::string &name) const> (&db::Layout::meta_info_value), gsi::arg ("name"),
+  gsi::method_ext ("meta_info_value", &layout_get_meta_info_value, gsi::arg ("name"),
     "@brief Gets the meta information value for a given name\n"
     "See \\LayoutMetaInfo for details about layouts and meta information.\n"
     "\n"
-    "If no meta information with the given name exists, an nil value will be returned.\n"
+    "If no meta information with the given name exists, a nil value will be returned.\n"
+    "A more generic version that delivers all fields of the meta information is \\meta_info.\n"
     "\n"
     "This method has been introduced in version 0.25. Starting with version 0.28.7, the value is of variant type instead of string only.\n"
   ) +
+  gsi::method_ext ("meta_info", &layout_get_meta_info, gsi::arg ("name"),
+    "@brief Gets the meta information for a given name\n"
+    "See \\LayoutMetaInfo for details about layouts and meta information.\n"
+    "\n"
+    "If no meta information with the given name exists, a default object with empty fields will be returned.\n"
+    "\n"
+    "This method has been introduced in version 0.28.7.\n"
+  ) +
   gsi::iterator_ext ("each_meta_info", &layout_each_meta_info,
     "@brief Iterates over the meta information of the layout\n"
     "See \\LayoutMetaInfo for details about layouts and meta information.\n"

src/db/db/gsiDeclDbMetaInfo.cc

@@ -27,9 +27,9 @@
 namespace gsi
 {
 
-static MetaInfo *layout_meta_info_ctor (const std::string &name, const std::string &value, const std::string &description)
+static MetaInfo *layout_meta_info_ctor (const std::string &name, const std::string &value, const std::string &description, bool persisted)
 {
-  return new MetaInfo (name, description, value);
+  return new MetaInfo (name, description, value, persisted);
 }
 
 static void layout_meta_set_name (MetaInfo *mi, const std::string &n)
@@ -62,13 +62,26 @@ static const std::string &layout_meta_get_description (const MetaInfo *mi)
   return mi->description;
 }
 
+static void layout_meta_set_persisted (MetaInfo *mi, bool f)
+{
+  mi->persisted = f;
+}
+
+static bool layout_meta_get_persisted (const MetaInfo *mi)
+{
+  return mi->persisted;
+}
+
 
 Class<MetaInfo> decl_LayoutMetaInfo ("db", "LayoutMetaInfo",
-  gsi::constructor ("new", &layout_meta_info_ctor, gsi::arg ("name"), gsi::arg ("value"), gsi::arg ("description", std::string ()),
+  gsi::constructor ("new", &layout_meta_info_ctor, gsi::arg ("name"), gsi::arg ("value"), gsi::arg ("description", std::string ()), gsi::arg ("persisted", false),
     "@brief Creates a layout meta info object\n"
     "@param name The name\n"
     "@param value The value\n"
     "@param description An optional description text\n"
+    "@param persisted If true, the meta information will be persisted in some file formats, like GDS2\n"
+    "\n"
+    "The 'persisted' attribute has been introduced in version 0.28.7.\n"
   ) +
   gsi::method_ext ("name", &layout_meta_get_name,
     "@brief Gets the name of the layout meta info object\n"
@@ -87,6 +100,14 @@ Class<MetaInfo> decl_LayoutMetaInfo ("db", "LayoutMetaInfo",
   ) +
   gsi::method_ext ("description=", &layout_meta_set_description,
     "@brief Sets the description of the layout meta info object\n"
+  ) +
+  gsi::method_ext ("persisted", &layout_meta_get_persisted,
+    "@brief Gets a value indicating whether the meta information will be persisted\n"
+    "This predicate was introduced in version 0.28.7.\n"
+  ) +
+  gsi::method_ext ("persisted=", &layout_meta_set_persisted,
+    "@brief Sets a value indicating whether the meta information will be persisted\n"
+    "This predicate was introduced in version 0.28.7.\n"
   ),
   "@brief A piece of layout meta information\n"
   "Layout meta information is basically additional data that can be attached to a layout. "
@@ -97,9 +118,10 @@ Class<MetaInfo> decl_LayoutMetaInfo ("db", "LayoutMetaInfo",
   "Meta information is identified by a unique name and carries a string value plus an optional description string. "
   "The description string is for information only and is not evaluated by code.\n"
   "\n"
-  "See also \\Layout#each_meta_info and \\Layout#meta_info_value and \\Layout#remove_meta_info"
+  "See also \\Layout#each_meta_info, \\Layout#meta_info_value, \\Layout#meta_info and \\Layout#remove_meta_info as "
+  "well as the corresponding \\Cell methods.\n"
   "\n"
-  "This class has been introduced in version 0.25."
+  "This class has been introduced in version 0.25 and was extended in version 0.28.7."
 );
 
 }

src/db/db/gsiDeclDbMetaInfo.h

@@ -35,17 +35,22 @@ namespace gsi
 
 struct MetaInfo
 {
-  MetaInfo (const std::string &n, const std::string &d, const tl::Variant &v)
+  MetaInfo (const std::string &n, const std::string &d, const tl::Variant &v, bool p)
-    : name (n), description (d), value (v)
+    : name (n), description (d), value (v), persisted (p)
+  { }
+
+  MetaInfo (const std::string &n, const db::MetaInfo &mi)
+    : name (n), description (mi.description), value (mi.value), persisted (mi.persisted)
   { }
 
   MetaInfo ()
-    : name (), description (), value ()
+    : name (), description (), value (), persisted (false)
   { }
 
   std::string name;
   std::string description;
   tl::Variant value;
+  bool persisted;
 };
 
 struct MetaInfoIterator
@@ -79,7 +84,7 @@ struct MetaInfoIterator
   MetaInfo operator* () const
   {
     if (mp_layout) {
-      return MetaInfo (mp_layout->meta_info_name (m_b->first), m_b->second.description, m_b->second.value);
+      return MetaInfo (mp_layout->meta_info_name (m_b->first), m_b->second);
     } else {
       return MetaInfo ();
     }

src/lay/lay/layLibraryController.cc

@@ -200,9 +200,10 @@ LibraryController::sync_files ()
             reader.read (lib->layout ());
 
             //  Use the libname if there is one
+            db::Layout::meta_info_name_id_type libname_name_id = lib->layout ().meta_info_name_id ("libname");
             for (db::Layout::meta_info_iterator m = lib->layout ().begin_meta (); m != lib->layout ().end_meta (); ++m) {
-              if (m->name == "libname" && ! m->value.empty ()) {
+              if (m->first == libname_name_id && ! m->second.value.is_nil ()) {
-                lib->set_name (m->value);
+                lib->set_name (m->second.value.to_string ());
                 break;
               }
             }

src/laybasic/laybasic/layLayoutViewBase.cc

@@ -3202,6 +3202,25 @@ LayoutViewBase::reload_layout (unsigned int cv_index)
   goto_view (state);
 }
 
+static void
+get_lyp_from_meta_info (const db::Layout &layout, std::string &lyp_file, bool &add_other_layers)
+{
+  db::Layout::meta_info_name_id_type layer_properties_file_name_id = layout.meta_info_name_id ("layer-properties-file");
+  db::Layout::meta_info_name_id_type layer_properties_add_other_layers_name_id = layout.meta_info_name_id ("layer-properties-add-other-layers");
+
+  for (db::Layout::meta_info_iterator meta = layout.begin_meta (); meta != layout.end_meta (); ++meta) {
+    if (meta->first == layer_properties_file_name_id) {
+      lyp_file = meta->second.value.to_string ();
+    }
+    if (meta->first == layer_properties_add_other_layers_name_id) {
+      try {
+        add_other_layers = meta->second.value.to_bool ();
+      } catch (...) {
+      }
+    }
+  }
+}
+
 unsigned int 
 LayoutViewBase::add_layout (lay::LayoutHandle *layout_handle, bool add_cellview, bool initialize_layers)
 {
@@ -3266,17 +3285,7 @@ LayoutViewBase::add_layout (lay::LayoutHandle *layout_handle, bool add_cellview,
       }
 
       //  Give the layout object a chance to specify a certain layer property file
-      for (db::Layout::meta_info_iterator meta = cv->layout ().begin_meta (); meta != cv->layout ().end_meta (); ++meta) {
+      get_lyp_from_meta_info (cv->layout (), lyp_file, add_other_layers);
-        if (meta->name == "layer-properties-file") {
-          lyp_file = meta->value;
-        }
-        if (meta->name == "layer-properties-add-other-layers") {
-          try {
-            tl::from_string (meta->value, add_other_layers);
-          } catch (...) {
-          }
-        }
-      }
 
       //  interpolate the layout properties file name
       tl::Eval expr;
@@ -3438,17 +3447,7 @@ LayoutViewBase::load_layout (const std::string &filename, const db::LoadLayoutOp
     }
 
     //  Give the layout object a chance to specify a certain layer property file
-    for (db::Layout::meta_info_iterator meta = cv->layout().begin_meta (); meta != cv->layout().end_meta (); ++meta) {
+    get_lyp_from_meta_info (cv->layout (), lyp_file, add_other_layers);
-      if (meta->name == "layer-properties-file") {
-        lyp_file = meta->value;
-      }
-      if (meta->name == "layer-properties-add-other-layers") {
-        try {
-          tl::from_string (meta->value, add_other_layers);
-        } catch (...) {
-        }
-      }
-    }
 
     //  interpolate the layout properties file name
     tl::Eval expr;

src/layui/layui/layLayoutStatisticsForm.cc

@@ -612,7 +612,7 @@ StatisticsSource::get (const std::string &url)
       }
 
       os <<       "<tr>" << std::endl
-         <<         "<td>" << layout.get_properties (*l).to_string () << "</td>" << std::endl
+         <<         "<td>" << tl::escaped_to_html (layout.get_properties (*l).to_string (), true) << "</td>" << std::endl
          // Boxes (total, single, array)
          <<         "<td>" << st_hier.box_total () << "<br></br>" << st_flat.box_total () << "</td>" << std::endl
          <<         "<td>" << st_hier.box_single () << "<br></br>" << st_flat.box_single () << "</td>" << std::endl
@@ -678,19 +678,19 @@ StatisticsSource::get (const std::string &url)
 
     os << "<html>" << std::endl
        <<   "<body>" << std::endl
-       <<     "<h2>" << tl::to_string (QObject::tr ("Common Statistics For '")) << m_h->name () << "'</h2>" << std::endl
+       <<     "<h2>" << tl::to_string (QObject::tr ("Common Statistics For '")) << tl::escaped_to_html (m_h->name (), true) << "'</h2>" << std::endl
        <<     "<p>" << std::endl
        <<     "<table>" << std::endl
        <<       "<tr>"
-       <<         "<td>" << tl::to_string (QObject::tr ("Path")) << ":&nbsp;</td><td>" << m_h->filename () << "</td>"
+       <<         "<td>" << tl::to_string (QObject::tr ("Path")) << ":&nbsp;</td><td>" << tl::escaped_to_html (m_h->filename (), true) << "</td>"
        <<       "</tr>" << std::endl;
     if (! m_h->save_options ().format ().empty ()) {
       os <<       "<tr>"
-         <<         "<td>" << tl::to_string (QObject::tr ("Format")) << ":&nbsp;</td><td>" << m_h->save_options ().format () << "</td>"
+         <<         "<td>" << tl::to_string (QObject::tr ("Format")) << ":&nbsp;</td><td>" << tl::escaped_to_html (m_h->save_options ().format (), true) << "</td>"
          <<       "</tr>" << std::endl;
     }
     os <<       "<tr>"
-       <<         "<td>" << tl::to_string (QObject::tr ("Technology")) << ":&nbsp;</td><td>" << m_h->technology ()->description () << format_tech_name (m_h->tech_name ()) << "</td>"
+       <<         "<td>" << tl::to_string (QObject::tr ("Technology")) << ":&nbsp;</td><td>" << tl::escaped_to_html (m_h->technology ()->description (), true) << tl::escaped_to_html (format_tech_name (m_h->tech_name ()), true) << "</td>"
        <<       "</tr>" << std::endl
        <<       "<tr>"
        <<         "<td>" << tl::to_string (QObject::tr ("Database unit")) << ":&nbsp;</td><td>" << tl::sprintf ("%.12g ", layout.dbu ()) << tl::to_string (QObject::tr ("micron")) << "</td>"
@@ -702,13 +702,17 @@ StatisticsSource::get (const std::string &url)
        <<         "<td>" << tl::to_string (QObject::tr ("Number of layers")) << ":&nbsp;</td><td>" << num_layers << "</td>"
        <<       "</tr>" << std::endl;
     for (db::Layout::meta_info_iterator meta = layout.begin_meta (); meta != layout.end_meta (); ++meta) {
-      os <<     "<tr><td>" << meta->description << "</td><td>" << meta->value << "</td></tr>" << std::endl;
+      std::string d = meta->second.description;
+      if (!d.empty ()) {
+        d = layout.meta_info_name (meta->first);
+      }
+      os <<     "<tr><td>" << tl::escaped_to_html (d, true) << "</td><td>" << tl::escaped_to_html (meta->second.value.to_string (), true) << "</td></tr>" << std::endl;
     }
     os <<     "</table>" << std::endl
        <<     "<h2>" << tl::to_string (QObject::tr ("Top Cells")) << "</h2>" << std::endl
        <<     "<table>" << std::endl;
     for (db::Layout::top_down_const_iterator tc = layout.begin_top_down (); tc != layout.end_top_cells (); ++tc) {
-      os <<     "<tr><td>" << layout.cell_name (*tc) << "</td></tr>" << std::endl;
+      os <<     "<tr><td>" << tl::escaped_to_html (layout.cell_name (*tc), true) << "</td></tr>" << std::endl;
     }
     os <<     "</table>" << std::endl;
     os <<     "</p>" << std::endl;
@@ -733,7 +737,7 @@ StatisticsSource::get (const std::string &url)
     if (! layers_sorted_by_ld.empty ()) {
 
       os <<     "<h2>" << tl::to_string (QObject::tr ("Layers (sorted by layer and datatype)")) << "</h2>" << std::endl
-         <<     "<p><a href=\"" << tl::to_string (s_per_layer_stat_path_ld) << "\">Detailed layer statistics</a></p>" << std::endl
+         <<     "<p><a href=\"" << tl::escaped_to_html (tl::to_string (s_per_layer_stat_path_ld), true) << "\">Detailed layer statistics</a></p>" << std::endl
          <<     "<p>" << std::endl
          <<     "<table>" << std::endl
          <<     "<tr><td><b>" << tl::to_string (QObject::tr ("Layer/Datatype")) << "</b>&nbsp;&nbsp;</td>";
@@ -748,7 +752,7 @@ StatisticsSource::get (const std::string &url)
           os << "<tr>"
              <<   "<td>" << tl::sprintf ("%d/%d", lp.layer, lp.datatype) << "</td>";
           if (! layers_with_oasis_names.empty ()) {
-            os <<   "<td>" << lp.name << "</td>";
+            os <<   "<td>" << tl::escaped_to_html (lp.name, true) << "</td>";
           }
           os << "</tr>" << std::endl;
         }
@@ -762,7 +766,7 @@ StatisticsSource::get (const std::string &url)
     if (! layers_with_oasis_names.empty ()) {
 
       os <<     "<h2>" << tl::to_string (QObject::tr ("Layers (sorted by layer names)")) << "</h2>" << std::endl
-         <<     "<p><a href=\"" << tl::to_string (s_per_layer_stat_path_name) << "\">Detailed layer statistics</a></p>" << std::endl
+         <<     "<p><a href=\"" << tl::escaped_to_html (tl::to_string (s_per_layer_stat_path_name), true) << "\">Detailed layer statistics</a></p>" << std::endl
          <<     "<p>" << std::endl
          <<     "<table>" << std::endl
          <<     "<tr><td><b>" << tl::to_string (QObject::tr ("Layer name")) << "</b>&nbsp;&nbsp;</td><td><b>" << tl::to_string (QObject::tr ("Layer/Datatype")) << "</b></td></tr>" << std::endl;
@@ -772,7 +776,7 @@ StatisticsSource::get (const std::string &url)
           const db::LayerProperties &lp = layout.get_properties (*i);
           if (! lp.name.empty ()) {
             os << "<tr>"
-               <<   "<td>" << lp.name << "</td>"
+               <<   "<td>" << tl::escaped_to_html (lp.name, true) << "</td>"
                <<   "<td>" << tl::sprintf ("%d/%d", lp.layer, lp.datatype) << "</td>"
                << "</tr>" << std::endl;
           }

src/plugins/streamers/gds2/db_plugin/dbGDS2ReaderBase.cc

@@ -185,8 +185,8 @@ GDS2ReaderBase::do_read (db::Layout &layout)
   unsigned int mod_time[6] = { 0, 0, 0, 0, 0, 0 };
   unsigned int access_time[6] = { 0, 0, 0, 0, 0, 0 };
   get_time (mod_time, access_time);
-  layout.add_meta_info (MetaInfo ("mod_time", tl::to_string (tr ("Modification Time")), tl::sprintf ("%d/%d/%d %d:%02d:%02d", mod_time[1], mod_time[2], mod_time[0], mod_time[3], mod_time[4], mod_time[5])));
+  layout.add_meta_info ("mod_time", MetaInfo (tl::to_string (tr ("Modification Time")), tl::sprintf ("%d/%d/%d %d:%02d:%02d", mod_time[1], mod_time[2], mod_time[0], mod_time[3], mod_time[4], mod_time[5])));
-  layout.add_meta_info (MetaInfo ("access_time", tl::to_string (tr ("Access Time")), tl::sprintf ("%d/%d/%d %d:%02d:%02d", access_time[1], access_time[2], access_time[0], access_time[3], access_time[4], access_time[5])));
+  layout.add_meta_info ("access_time", MetaInfo (tl::to_string (tr ("Access Time")), tl::sprintf ("%d/%d/%d %d:%02d:%02d", access_time[1], access_time[2], access_time[0], access_time[3], access_time[4], access_time[5])));
 
   long attr = 0;
   db::PropertiesRepository::properties_set layout_properties;
@@ -234,9 +234,9 @@ GDS2ReaderBase::do_read (db::Layout &layout)
       double dbuu = get_double ();
       double dbum = get_double ();
       
-      layout.add_meta_info (MetaInfo ("dbuu", tl::to_string (tr ("Database unit in user units")), tl::to_string (dbuu)));
+      layout.add_meta_info ("dbuu", MetaInfo (tl::to_string (tr ("Database unit in user units")), tl::to_string (dbuu)));
-      layout.add_meta_info (MetaInfo ("dbum", tl::to_string (tr ("Database unit in meter")), tl::to_string (dbum)));
+      layout.add_meta_info ("dbum", MetaInfo (tl::to_string (tr ("Database unit in meter")), tl::to_string (dbum)));
-      layout.add_meta_info (MetaInfo ("libname", tl::to_string (tr ("Library name")), m_libname));
+      layout.add_meta_info ("libname", MetaInfo (tl::to_string (tr ("Library name")), m_libname));
 
       m_dbuu = dbuu;
       m_dbu = dbum * 1e6; /*in micron*/

src/plugins/streamers/gds2/db_plugin/dbGDS2WriterBase.cc

@@ -86,9 +86,9 @@ GDS2WriterBase::write (db::Layout &layout, tl::OutputStream &stream, const db::S
 
   db::GDS2WriterOptions gds2_options = options.get_options<db::GDS2WriterOptions> ();
 
-  layout.add_meta_info (MetaInfo ("dbuu", tl::to_string (tr ("Database unit in user units")), tl::to_string (dbu / std::max (1e-9, gds2_options.user_units))));
+  layout.add_meta_info ("dbuu", MetaInfo (tl::to_string (tr ("Database unit in user units")), tl::to_string (dbu / std::max (1e-9, gds2_options.user_units))));
-  layout.add_meta_info (MetaInfo ("dbum", tl::to_string (tr ("Database unit in meter")), tl::to_string (dbu * 1e-6)));
+  layout.add_meta_info ("dbum", MetaInfo (tl::to_string (tr ("Database unit in meter")), tl::to_string (dbu * 1e-6)));
-  layout.add_meta_info (MetaInfo ("libname", tl::to_string (tr ("Library name")), gds2_options.libname));
+  layout.add_meta_info ("libname", MetaInfo (tl::to_string (tr ("Library name")), gds2_options.libname));
 
   std::vector <std::pair <unsigned int, db::LayerProperties> > layers;
   options.get_valid_layers (layout, layers, db::SaveLayoutOptions::LP_AssignNumber);
@@ -123,8 +123,8 @@ GDS2WriterBase::write (db::Layout &layout, tl::OutputStream &stream, const db::S
   }
 
   std::string str_time = tl::sprintf ("%d/%d/%d %d:%02d:%02d", time_data[1], time_data[2], time_data[0], time_data[3], time_data[4], time_data[5]); 
-  layout.add_meta_info (MetaInfo ("mod_time", tl::to_string (tr ("Modification Time")), str_time));
+  layout.add_meta_info ("mod_time", MetaInfo (tl::to_string (tr ("Modification Time")), str_time));
-  layout.add_meta_info (MetaInfo ("access_time", tl::to_string (tr ("Access Time")), str_time));
+  layout.add_meta_info ("access_time", MetaInfo (tl::to_string (tr ("Access Time")), str_time));
 
   bool multi_xy = gds2_options.multi_xy_records;
   size_t max_cellname_length = std::max (gds2_options.max_cellname_length, (unsigned int)8);

src/plugins/streamers/gds2/lay_plugin/layGDS2WriterPlugin.cc

@@ -145,9 +145,10 @@ public:
     //  Initialize the libname property from meta data with key "libname".
     db::GDS2WriterOptions *options = dynamic_cast<db::GDS2WriterOptions *> (o);
     if (options) {
+      db::Layout::meta_info_name_id_type libname_name_id = lh.layout().meta_info_name_id ("libname");
       for (db::Layout::meta_info_iterator meta = lh.layout().begin_meta (); meta != lh.layout().end_meta (); ++meta) {
-        if (meta->name == "libname" && !meta->value.empty ()) {
+        if (meta->first == libname_name_id && !meta->second.value.is_nil ()) {
-          options->libname = meta->value;
+          options->libname = meta->second.value.to_string ();
         }
       }
     }

src/plugins/streamers/gds2/unit_tests/dbGDS2Reader.cc

@@ -229,7 +229,7 @@ TEST(1)
   db::LayerMap map = reader.read (layout);
 
   EXPECT_EQ (fabs (layout.dbu () / 0.001 - 1.0) < 1e-6, true);
-  EXPECT_EQ (layout.meta_info_value ("libname"), "LIB.DB");
+  EXPECT_EQ (layout.meta_info ("libname").value.to_string (), "LIB.DB");
 
   EXPECT_EQ (layout.layers (), size_t (11));
   EXPECT_EQ (map.mapping_str (0), "2/0 : 2/0");
@@ -289,7 +289,7 @@ TEST(2)
     db::Reader reader (file);
     map = reader.read (layout_none, options);
     EXPECT_EQ (fabs (layout_none.dbu () / 0.001 - 1.0) < 1e-6, true);
-    EXPECT_EQ (layout.meta_info_value ("libname"), "LIB.DB");
+    EXPECT_EQ (layout.meta_info ("libname").value.to_string (), "LIB.DB");
   }
 
   EXPECT_EQ (layout_none.layers (), size_t (0));

src/plugins/streamers/magic/db_plugin/dbMAGReader.cc

@@ -316,7 +316,7 @@ MAGReader::do_read_part (db::Layout &layout, db::cell_index_type cell_index, tl:
     error (tl::to_string (tr ("Could not find 'magic' header line - is this a MAGIC file?")));
   }
 
-  layout.add_meta_info (db::MetaInfo ("lambda", "lambda value (tech scaling)", tl::to_string (m_lambda)));
+  layout.add_meta_info ("lambda", db::MetaInfo ("lambda value (tech scaling)", tl::to_string (m_lambda)));
 
   bool valid_layer = false;
   unsigned int current_layer = 0;
@@ -339,11 +339,11 @@ MAGReader::do_read_part (db::Layout &layout, db::cell_index_type cell_index, tl:
       if (&m_stream == &stream) {
 
         //  initial file - store technology
-        layout.add_meta_info (db::MetaInfo ("magic_technology", tl::to_string (tr ("MAGIC technology string")), m_tech));
+        layout.add_meta_info ("magic_technology", db::MetaInfo (tl::to_string (tr ("MAGIC technology string")), m_tech));
 
         //  propose this is the KLayout technology unless a good one is given
         if (! mp_klayout_tech) {
-          layout.add_meta_info (db::MetaInfo ("technology", tl::to_string (tr ("Technology name")), m_tech));
+          layout.add_meta_info ("technology", db::MetaInfo (tl::to_string (tr ("Technology name")), m_tech));
         }
 
       }
@@ -357,7 +357,7 @@ MAGReader::do_read_part (db::Layout &layout, db::cell_index_type cell_index, tl:
 
       if (&m_stream == &stream) {
         //  initial file - store timestamp
-        layout.add_meta_info (db::MetaInfo ("magic_timestamp", "MAGIC main file timestamp", tl::to_string (ts)));
+        layout.add_meta_info ("magic_timestamp", db::MetaInfo ("MAGIC main file timestamp", tl::to_string (ts)));
       }
 
       ex.expect_end ();

src/plugins/streamers/magic/db_plugin/dbMAGWriter.cc

@@ -82,11 +82,14 @@ MAGWriter::write (db::Layout &layout, tl::OutputStream &stream, const db::SaveLa
 
   double lambda = m_options.lambda;
   if (lambda <= 0.0) {
-    const std::string &lv = layout.meta_info_value ("lambda");
+    const tl::Variant &lv = layout.meta_info ("lambda").value;
-    if (lv.empty ()) {
+    if (lv.is_nil ()) {
       throw tl::Exception (tl::to_string (tr ("No lambda value configured for MAG writer and no 'lambda' metadata present in layout.")));
+    } else if (lv.is_a_string ()) {
+      tl::from_string (lv.to_string (), lambda);
+    } else if (lv.can_convert_to_double ()) {
+      lambda = lv.to_double ();
     }
-    tl::from_string (lv, lambda);
   }
 
   m_sf = layout.dbu () / lambda;

src/plugins/streamers/pcb/db_plugin/dbGerberImporter.cc

@@ -1146,7 +1146,7 @@ public:
 
     std::string lyr_file = data.get_layer_properties_file ();
     if (! lyr_file.empty ()) {
-      layout.add_meta_info (db::MetaInfo ("layer-properties-file", "Layer Properties File", lyr_file));
+      layout.add_meta_info ("layer-properties-file", db::MetaInfo ("Layer Properties File", lyr_file));
     }
 
     return m_layers;