implement $ping on proxy server

README.md

@@ -283,7 +283,7 @@ Some commands only work on the game server and not on the proxy server. The chat
 
 * Information commands
     * `$li`: Shows basic information about the lobby or game you're in. If you're on the proxy server, shows information about your connection instead (remote Guild Card number, client ID, etc.).
-    * `$ping` (game server only): Shows round-trip ping time from the server to you.
+    * `$ping`: Shows round-trip ping time from the server to you. On the proxy server, shows the ping time from you to the proxy and from the proxy to the server.
     * `$matcount` (game server only): Shows how many of each type of material you've used.
     * `$what` (game server only): Shows the type, name, and stats of the nearest item on the ground.
     * `$where` (game server only): Shows your current floor number and coordinates. Mainly useful for debugging.

src/ChatCommands.cc

@@ -168,6 +168,15 @@ static void server_command_ping(shared_ptr<Client> c, const std::string&) {
   send_command(c, 0x1D, 0x00);
 }
 
+static void proxy_command_ping(shared_ptr<ProxyServer::LinkedSession> ses, const std::string&) {
+  ses->client_ping_start_time = now();
+  ses->server_ping_start_time = now();
+
+  C_GuildCardSearch_40 cmd = {0x00010000, ses->remote_guild_card_number, ses->remote_guild_card_number};
+  ses->client_channel.send(0x1D, 0x00);
+  ses->server_channel.send(0x40, 0x00, &cmd, sizeof(cmd));
+}
+
 static void proxy_command_lobby_info(shared_ptr<ProxyServer::LinkedSession> ses, const std::string&) {
   string msg;
   // On non-masked-GC sessions (BB), there is no remote Guild Card number, so we
@@ -1883,7 +1892,7 @@ static const unordered_map<string, ChatCommandDefinition> chat_commands({
     {"$password", {server_command_password, nullptr}},
     {"$patch", {server_command_patch, proxy_command_patch}},
     {"$persist", {server_command_persist, nullptr}},
-    {"$ping", {server_command_ping, nullptr}},
+    {"$ping", {server_command_ping, proxy_command_ping}},
     {"$playrec", {server_command_playrec, nullptr}},
     {"$qcall", {server_command_qcall, proxy_command_qcall}},
     {"$qcheck", {server_command_qcheck, nullptr}},

src/ProxyCommands.cc

@@ -119,6 +119,12 @@ static HandlerResult C_05(shared_ptr<ProxyServer::LinkedSession> ses, uint16_t,
 }
 
 static HandlerResult C_1D(shared_ptr<ProxyServer::LinkedSession> ses, uint16_t, uint32_t, string&) {
+  if (ses->client_ping_start_time) {
+    uint64_t ping_usecs = now() - ses->client_ping_start_time;
+    ses->client_ping_start_time = 0;
+    double ping_ms = static_cast<double>(ping_usecs) / 1000.0;
+    send_text_message_printf(ses->client_channel, "To proxy: %gms", ping_ms);
+  }
   return ses->config.check_flag(Client::Flag::PROXY_SUPPRESS_CLIENT_PINGS)
       ? HandlerResult::Type::SUPPRESS
       : HandlerResult::Type::FORWARD;
@@ -566,19 +572,32 @@ static HandlerResult S_V123_06(shared_ptr<ProxyServer::LinkedSession> ses, uint1
 
 template <typename CmdT>
 static HandlerResult S_41(shared_ptr<ProxyServer::LinkedSession> ses, uint16_t, uint32_t, string& data) {
-  bool modified = false;
   if (ses->license) {
     auto& cmd = check_size_t<CmdT>(data);
-    if (cmd.searcher_guild_card_number == ses->remote_guild_card_number) {
-      cmd.searcher_guild_card_number = ses->license->serial_number;
-      modified = true;
-    }
-    if (cmd.result_guild_card_number == ses->remote_guild_card_number) {
-      cmd.result_guild_card_number = ses->license->serial_number;
-      modified = true;
+    if ((cmd.searcher_guild_card_number == ses->remote_guild_card_number) &&
+        (cmd.result_guild_card_number == ses->remote_guild_card_number) &&
+        ses->server_ping_start_time) {
+      uint64_t ping_usecs = now() - ses->server_ping_start_time;
+      ses->server_ping_start_time = 0;
+      double ping_ms = static_cast<double>(ping_usecs) / 1000.0;
+      send_text_message_printf(ses->client_channel, "To server: %gms", ping_ms);
+      return HandlerResult::Type::SUPPRESS;
+
+    } else {
+      bool modified = false;
+      if (cmd.searcher_guild_card_number == ses->remote_guild_card_number) {
+        cmd.searcher_guild_card_number = ses->license->serial_number;
+        modified = true;
+      }
+      if (cmd.result_guild_card_number == ses->remote_guild_card_number) {
+        cmd.result_guild_card_number = ses->license->serial_number;
+        modified = true;
+      }
+      return modified ? HandlerResult::Type::MODIFIED : HandlerResult::Type::FORWARD;
     }
+  } else {
+    return HandlerResult::Type::FORWARD;
   }
-  return modified ? HandlerResult::Type::MODIFIED : HandlerResult::Type::FORWARD;
 }
 
 constexpr on_command_t S_DGX_41 = &S_41<S_GuildCardSearchResult_DC_V3_41>;

src/ProxyServer.hh

@@ -91,6 +91,8 @@ public:
     bool is_in_game;
     bool is_in_quest;
     uint8_t difficulty;
+    uint64_t client_ping_start_time = 0;
+    uint64_t server_ping_start_time = 0;
 
     std::shared_ptr<PSOBBMultiKeyDetectorEncryption> detector_crypt;