Make DC V2 EXP dispatcher rate-aware

src/ReceiveSubcommands.cc

@@ -3656,11 +3656,14 @@ static asio::awaitable<void> dispatch_dc_v2_exp_patch(shared_ptr<Client> c) {
       co_return;
   }
 
-  string key = "PsoPeepsV2EXP_internal_10x_";
+  auto server_state = c->require_server_state();
+
+  string key = "PsoPeepsV2EXP_internal_";
+  key += std::to_string(server_state->psopeeps_dcv2_exp_multiplier);
+  key += "x_";
   key += diff_str;
 
   try {
-    auto server_state = c->require_server_state();
     auto fn = server_state->client_functions->get(key, c->specific_version);
     co_await send_function_call(c, fn);
   } catch (const out_of_range&) {

src/ServerState.cc

@@ -878,6 +878,10 @@ void ServerState::load_config_early() {
   this->client_ping_interval_usecs = this->config_json->get_int("ClientPingInterval", 30000000);
   this->client_idle_timeout_usecs = this->config_json->get_int("ClientIdleTimeout", 60000000);
   this->patch_client_idle_timeout_usecs = this->config_json->get_int("PatchClientIdleTimeout", 300000000);
+  this->psopeeps_dcv2_exp_multiplier = this->config_json->get_int("PsoPeepsDCV2EXPMultiplier", 5);
+  if ((this->psopeeps_dcv2_exp_multiplier != 5) && (this->psopeeps_dcv2_exp_multiplier != 10)) {
+    throw runtime_error("PsoPeepsDCV2EXPMultiplier must be 5 or 10");
+  }
 
   this->ip_stack_debug = this->config_json->get_bool("IPStackDebug", false);
   this->allow_unregistered_users = this->config_json->get_bool("AllowUnregisteredUsers", false);

src/ServerState.hh

@@ -123,6 +123,7 @@ struct ServerState : public std::enable_shared_from_this<ServerState> {
   uint64_t client_ping_interval_usecs = 30000000;
   uint64_t client_idle_timeout_usecs = 60000000;
   uint64_t patch_client_idle_timeout_usecs = 300000000;
+  uint64_t psopeeps_dcv2_exp_multiplier = 5;
   bool is_debug = false;
   bool ip_stack_debug = false;
   bool allow_unregistered_users = false;