send server brand during login

* send server brand to client

* send brand regardless of `0x02` being recieved by server or not

* send brand regardless of `0x02` being recieved by server or not
+ if statement to match previous lines

* ifdef check for brand sending

* commit main.c for ifdef check (i forgot)

* commit main.c for ifdef check (i forgot)

* change sc_pluginMessage to sc_sendPluginMessage

- added params to it for use in other cases
- other changes to fit PR reviews

* revert .gitignore

* revert unrelated changes

* send byte instead of varint for constant packet id

* gate declaration of brand string behind ifdef

* make logging consistent with codebase

---------

Co-authored-by: p2r3 <p2r3@p2r3.com>

Author: b1bradders

include/globals.h

@@ -102,6 +102,11 @@
 // clients from Keep Alive packets.
 #define NETWORK_TIMEOUT_TIME 15000000
 
+// If defined, sends the server brand to clients. Doesn't do much, but will
+// show up in the top-left of the F3/debug menu, in the Minecraft client.
+// You can change the brand string in the "brand" variable in src/globals.c
+#define SEND_BRAND
+
 // If defined, rebroadcasts ALL incoming movement updates, disconnecting
 // movement from the server's tickrate. This makes movement much smoother
 // on very low tickrates, at the cost of potential network instability when
@@ -170,6 +175,11 @@ extern uint32_t server_ticks;
 extern char motd[];
 extern uint8_t motd_len;
 
+#ifdef SEND_BRAND
+  extern char brand[];
+  extern uint8_t brand_len;
+#endif
+
 extern uint16_t client_count;
 
 typedef struct {

include/packets.h

@@ -26,6 +26,7 @@ int cs_playerCommand (int client_fd);
 int sc_statusResponse (int client_fd);
 int sc_loginSuccess (int client_fd, uint8_t *uuid, char *name);
 int sc_knownPacks (int client_fd);
+int sc_sendPluginMessage (int client_fd, const char *channel, const uint8_t *data, size_t data_len);
 int sc_finishConfiguration (int client_fd);
 int sc_loginPlay (int client_fd);
 int sc_synchronizePlayerPosition (int client_fd, double x, double y, double z, float yaw, float pitch);

src/globals.c

@@ -35,6 +35,11 @@ uint32_t server_ticks = 0;
 char motd[] = { "A bareiron server" };
 uint8_t motd_len = sizeof(motd) - 1;
 
+#ifdef SEND_BRAND
+  char brand[] = { "bareiron" };
+  uint8_t brand_len = sizeof(brand) - 1;
+#endif
+
 uint16_t client_count;
 
 BlockChange block_changes[MAX_BLOCK_CHANGES];

src/main.c

@@ -85,6 +85,10 @@ void handlePacket (int client_fd, int length, int packet_id, int state) {
         if (cs_clientInformation(client_fd)) break;
         if (sc_knownPacks(client_fd)) break;
         if (sc_registries(client_fd)) break;
+
+        #ifdef SEND_BRAND
+        if (sc_sendPluginMessage(client_fd, "minecraft:brand", brand, brand_len)) break;
+        #endif
       }
       break;
 

src/packets.c

@@ -157,6 +157,23 @@ int cs_pluginMessage (int client_fd) {
   return 0;
 }
 
+// S->C Clientbound Plugin Message
+int sc_sendPluginMessage (int client_fd, const char *channel, const uint8_t *data, size_t data_len) {
+  printf("Sending Plugin Message\n\n");
+  int channel_len = (int)strlen(channel);
+
+  writeVarInt(client_fd, 1 + sizeVarInt(channel_len) + channel_len + sizeVarInt(data_len) + data_len);
+  writeByte(client_fd, 0x01);
+
+  writeVarInt(client_fd, channel_len);
+  send_all(client_fd, channel, channel_len);
+
+  writeVarInt(client_fd, data_len);
+  send_all(client_fd, data, data_len);
+
+  return 0;
+}
+
 // S->C Finish Configuration
 int sc_finishConfiguration (int client_fd) {
   writeVarInt(client_fd, 1);