Merge pull request #1332 from cogutvalera/issue_1314

Terminate block production loop when shutting down witness plugin #1314

Author: abitmore

libraries/plugins/witness/include/graphene/witness/witness.hpp

@@ -41,22 +41,14 @@ namespace block_production_condition
       no_private_key = 4,
       low_participation = 5,
       lag = 6,
-      exception_producing_block = 7
+      exception_producing_block = 7,
+      shutdown = 8
    };
 }
 
 class witness_plugin : public graphene::app::plugin {
 public:
-   ~witness_plugin() {
-      try {
-         if( _block_production_task.valid() )
-            _block_production_task.cancel_and_wait(__FUNCTION__);
-      } catch(fc::canceled_exception&) {
-         //Expected exception. Move along.
-      } catch(fc::exception& e) {
-         edump((e.to_detail_string()));
-      }
-   }
+   ~witness_plugin() { stop_block_production(); }
 
    std::string plugin_name()const override;
 
@@ -66,6 +58,7 @@ class witness_plugin : public graphene::app::plugin {
       ) override;
 
    void set_block_production(bool allow) { _production_enabled = allow; }
+   void stop_block_production();
 
    virtual void plugin_initialize( const boost::program_options::variables_map& options ) override;
    virtual void plugin_startup() override;
@@ -84,6 +77,7 @@ class witness_plugin : public graphene::app::plugin {
 
    boost::program_options::variables_map _options;
    bool _production_enabled = false;
+   bool _shutting_down = false;
    uint32_t _required_witness_participation = 33 * GRAPHENE_1_PERCENT;
    uint32_t _production_skip_flags = graphene::chain::database::skip_nothing;
 

libraries/plugins/witness/witness.cpp

@@ -143,7 +143,21 @@ void witness_plugin::plugin_startup()
 
 void witness_plugin::plugin_shutdown()
 {
-   // nothing to do
+   stop_block_production();
+}
+
+void witness_plugin::stop_block_production()
+{
+   _shutting_down = true;
+   
+   try {
+      if( _block_production_task.valid() )
+         _block_production_task.cancel_and_wait(__FUNCTION__);
+   } catch(fc::canceled_exception&) {
+      //Expected exception. Move along.
+   } catch(fc::exception& e) {
+      edump((e.to_detail_string()));
+   }
 }
 
 void witness_plugin::refresh_witness_key_cache()
@@ -161,6 +175,8 @@ void witness_plugin::refresh_witness_key_cache()
 
 void witness_plugin::schedule_production_loop()
 {
+   if (_shutting_down) return;
+
    //Schedule for the next second's tick regardless of chain state
    // If we would wait less than 50ms, wait for the whole second.
    fc::time_point now = fc::time_point::now();
@@ -176,6 +192,8 @@ void witness_plugin::schedule_production_loop()
 
 block_production_condition::block_production_condition_enum witness_plugin::block_production_loop()
 {
+   if (_shutting_down) return block_production_condition::block_production_condition_enum::shutdown;
+
    block_production_condition::block_production_condition_enum result;
    fc::limited_mutable_variant_object capture( GRAPHENE_MAX_NESTED_OBJECTS );
    try