Pass initial position when loading the provider

Having initial position as a part of server_state does not allow
restarting the provider from different startup position without
either reconstructing server_state or adding setter method for
initial position. As the only use for initial_position in server state
was to pass it to provider during provider load, it makes more sense
to have the initial position to be passed as an argument to
server_state load_provider() method.

dbsim/db_server_state.hpp

@@ -45,7 +45,6 @@ namespace db
                 "",
                 address,
                 working_dir,
-                wsrep::gtid::undefined(),
                 1,
                 wsrep::server_state::rm_async)
             , mutex_()

dbsim/db_simulator.cpp

@@ -137,7 +137,8 @@ void db::simulator::start()
         std::string server_options(params_.wsrep_provider_options);
 
         if (server.server_state().load_provider(
-                params_.wsrep_provider, server_options))
+                params_.wsrep_provider, server_options,
+                wsrep::gtid::undefined()))
         {
             throw wsrep::runtime_error("Failed to load provider");
         }

include/wsrep/provider.hpp

@@ -362,7 +362,8 @@ namespace wsrep
         static provider* make_provider(
             wsrep::server_state&,
             const std::string& provider_spec,
-            const std::string& provider_options);
+            const std::string& provider_options,
+            const wsrep::gtid& initial_position);
     protected:
         wsrep::server_state& server_state_;
     };

include/wsrep/server_state.hpp

@@ -212,11 +212,6 @@ namespace wsrep
          */
         const std::string& working_dir() const { return working_dir_; }
 
-        /**
-         * Return initial position for server.
-         */
-        const wsrep::gtid& initial_position() const
-        { return initial_position_; }
         /**
          * Return maximum protocol version.
          */
@@ -261,7 +256,8 @@ namespace wsrep
          * @return Zero on success, non-zero on error.
          */
         int load_provider(const std::string& provider,
-                          const std::string& provider_options);
+                          const std::string& provider_options,
+                          const wsrep::gtid& intial_position);
 
         void unload_provider();
 
@@ -557,7 +553,7 @@ namespace wsrep
                      const std::string& incoming_address,
                      const std::string& address,
                      const std::string& working_dir,
-                     const wsrep::gtid& initial_position,
+                     // const wsrep::gtid& initial_position,
                      int max_protocol_version,
                      enum rollback_mode rollback_mode)
             : mutex_(mutex)
@@ -567,7 +563,7 @@ namespace wsrep
             , state_hist_()
             , state_waiters_(n_states_)
             , bootstrap_()
-            , initial_position_(initial_position)
+              // , initial_position_(initial_position)
             , init_initialized_()
             , init_synced_()
             , sst_gtid_()
@@ -628,7 +624,7 @@ namespace wsrep
         std::vector<enum state> state_hist_;
         mutable std::vector<int> state_waiters_;
         bool bootstrap_;
-        const wsrep::gtid initial_position_;
+        // const wsrep::gtid initial_position_;
         bool init_initialized_;
         bool init_synced_;
         wsrep::gtid sst_gtid_;

src/provider.cpp

@@ -25,12 +25,13 @@
 wsrep::provider* wsrep::provider::make_provider(
     wsrep::server_state& server_state,
     const std::string& provider_spec,
-    const std::string& provider_options)
+    const std::string& provider_options,
+    const wsrep::gtid& initial_position)
 {
     try
     {
         return new wsrep::wsrep_provider_v26(
-            server_state, provider_options, provider_spec);
+            server_state, provider_options, provider_spec, initial_position);
     }
     catch (const wsrep::runtime_error& e)
     {

src/server_state.cpp

@@ -332,14 +332,15 @@ static int apply_toi(wsrep::provider& provider,
 //////////////////////////////////////////////////////////////////////////////
 
 int wsrep::server_state::load_provider(const std::string& provider_spec,
-                                       const std::string& provider_options)
+                                       const std::string& provider_options,
+                                       const wsrep::gtid& initial_position)
 {
     wsrep::log_info() << "Loading provider "
                       << provider_spec
                       << "initial position: "
-                      << initial_position_;
+                      << initial_position;
     provider_ = wsrep::provider::make_provider(
-        *this, provider_spec, provider_options);
+        *this, provider_spec, provider_options, initial_position);
     return (provider_ ? 0 : 1);
 }
 

src/wsrep_provider_v26.cpp

@@ -546,15 +546,16 @@ namespace
 wsrep::wsrep_provider_v26::wsrep_provider_v26(
     wsrep::server_state& server_state,
     const std::string& provider_options,
-    const std::string& provider_spec)
+    const std::string& provider_spec,
+    const wsrep::gtid& initial_position)
     : provider(server_state)
     , wsrep_()
 {
     wsrep_gtid_t state_id;
     std::memcpy(state_id.uuid.data,
-                server_state.initial_position().id().data(),
+                initial_position.id().data(),
                 sizeof(state_id.uuid.data));
-    state_id.seqno = server_state.initial_position().seqno().get();
+    state_id.seqno = initial_position.seqno().get();
     struct wsrep_init_args init_args;
     memset(&init_args, 0, sizeof(init_args));
     init_args.app_ctx = &server_state;

src/wsrep_provider_v26.hpp

@@ -31,7 +31,7 @@ namespace wsrep
     public:
 
         wsrep_provider_v26(wsrep::server_state&, const std::string&,
-                           const std::string&);
+                           const std::string&, const wsrep::gtid&);
         ~wsrep_provider_v26();
         enum wsrep::provider::status
         connect(const std::string&, const std::string&, const std::string&,

test/mock_server_state.hpp

@@ -214,7 +214,6 @@ namespace wsrep
                           wsrep::server_service& server_service)
             : wsrep::server_state(mutex_, cond_, server_service,
                                   name, "", "", "./",
-                                  wsrep::gtid::undefined(),
                                   1,
                                   rollback_mode)
             , mutex_()