Make sure not to process relations twice in append mode

In append mode relations could be processed twice if they are in the
input and also the parent of a node or way in the input. With this
change we are removing all ids of changed relations from the list of
pending relations before processing them.

Fixes #423.

Author: joto

src/dependency-manager.cpp

@@ -23,6 +23,11 @@ void full_dependency_manager_t::way_changed(osmid_t id)
     m_changed_ways.set(id);
 }
 
+void full_dependency_manager_t::relation_changed(osmid_t id)
+{
+    m_changed_relations.set(id);
+}
+
 void full_dependency_manager_t::after_nodes()
 {
     if (m_changed_nodes.empty()) {
@@ -76,6 +81,16 @@ void full_dependency_manager_t::after_ways()
     }
 }
 
+void full_dependency_manager_t::after_relations()
+{
+    // Remove ids from changed relations in the input data from
+    // m_rels_pending_tracker, because they have already been processed.
+    m_rels_pending_tracker =
+        set_diff(m_rels_pending_tracker, m_changed_relations);
+
+    m_changed_relations.clear();
+}
+
 void full_dependency_manager_t::mark_parent_relations_as_pending(
     osmium::index::IdSetSmall<osmid_t> const &way_ids)
 {

src/dependency-manager.hpp

@@ -52,8 +52,11 @@ class dependency_manager_t
      */
     virtual void way_changed(osmid_t) {}
 
+    virtual void relation_changed(osmid_t) {}
+
     virtual void after_nodes() {}
     virtual void after_ways() {}
+    virtual void after_relations() {}
 
     virtual void mark_parent_relations_as_pending(
         osmium::index::IdSetSmall<osmid_t> const & /*way_ids*/)
@@ -102,9 +105,11 @@ class full_dependency_manager_t : public dependency_manager_t
 
     void node_changed(osmid_t id) override;
     void way_changed(osmid_t id) override;
+    void relation_changed(osmid_t id) override;
 
     void after_nodes() override;
     void after_ways() override;
+    void after_relations() override;
 
     void mark_parent_relations_as_pending(
         osmium::index::IdSetSmall<osmid_t> const &ids) override;
@@ -145,6 +150,13 @@ class full_dependency_manager_t : public dependency_manager_t
      */
     osmium::index::IdSetSmall<osmid_t> m_changed_ways;
 
+    /**
+     * In append mode all new and changed relations will be added to this.
+     * This is then used to remove already processed relations from the
+     * pending list.
+     */
+    osmium::index::IdSetSmall<osmid_t> m_changed_relations;
+
     osmium::index::IdSetSmall<osmid_t> m_ways_pending_tracker;
     osmium::index::IdSetSmall<osmid_t> m_rels_pending_tracker;
 };

src/osmdata.cpp

@@ -141,12 +141,19 @@ void osmdata_t::relation(osmium::Relation const &rel)
         } else {
             m_output->relation_delete(rel.id());
         }
+        m_dependency_manager->relation_changed(rel.id());
     } else if (has_tags_or_attrs) {
         m_output->relation_add(rel);
     }
 }
 
-void osmdata_t::after_relations() { m_mid->after_relations(); }
+void osmdata_t::after_relations()
+{
+    m_mid->after_relations();
+    if (m_append) {
+        m_dependency_manager->after_relations();
+    }
+}
 
 void osmdata_t::start() const
 {