Feature: [Network] Optionally send NewGRF names with NewGRFs in GameInfo

Before 8a2da49 the NewGRF names were synchronized using UDP packets, however
those have been removed. With this a new version of the GameInfo packet is
introduced that allows to specify the type of serialisation happens for
NewGRFs. Either only the GRF ID and checksum, or those two plus the name of
the NewGRF.
On this request for local servers will send the NewGRFs names.
The Game Coordinator will get the names on the first registration, and after
that only the GRF ID and checksum.

1 files changed, 38 insertions, 8 deletions

diff --git a/src/network/core/game_info.h b/src/network/core/game_info.h
index a1719acd7..1d17b6f41 100644
--- a/src/network/core/game_info.h
+++ b/src/network/core/game_info.h
@@ -25,14 +25,27 @@
  * Version: Bytes:  Description:
  *   all      1       the version of this packet's structure
  *
+ *   6+       1       type of storage for the NewGRFs below:
+ *                      0 = NewGRF ID and MD5 checksum.
+ *                          Used as default for version 5 and below, and for
+ *                          later game updates to the Game Coordinator.
+ *                      1 = NewGRF ID, MD5 checksum and name.
+ *                          Used for direct requests and the first game
+ *                          update to Game Coordinator.
+ *
  *   5+       4       version number of the Game Script (-1 is case none is selected).
  *   5+       var     string with the name of the Game Script.
  *
- *   4+       1       number of GRFs attached (n)
- *   4+       n * 20  unique identifier for GRF files. Consists of:
- *                     - one 4 byte variable with the GRF ID
- *                     - 16 bytes (sent sequentially) for the MD5 checksum
- *                       of the GRF
+ *   4+       1       number of GRFs attached (n).
+ *   4+       n * var identifiers for GRF files. Consists of:
+ *                    Note: the 'vN' refers to packet version and 'type'
+ *                    refers to the v6+ type of storage for the NewGRFs.
+ *                     - 4 byte variable with the GRF ID.
+ *                       For v4, v5, and v6+ in case of type 0 and/or type 1.
+ *                     - 16 bytes with the MD5 checksum of the GRF.
+ *                       For v4, v5, and v6+ in case of type 0 and/or type 1.
+ *                     - string with name of NewGRF.
+ *                       For v6+ in case of type 1.
  *
  *   3+       4       current game date in days since 1-1-0 (DMY)
  *   3+       4       game introduction date in days since 1-1-0 (DMY)
@@ -43,7 +56,7 @@
  *
  *   1+       var     string with the name of the server
  *   1+       var     string with the revision of the server
- *   1+       1       the language run on the server
+ *   1 - 5    1       the language run on the server
  *                    (0 = any, 1 = English, 2 = German, 3 = French)
  *   1+       1       whether the server uses a password (0 = no, 1 = yes)
  *   1+       1       maximum number of clients allowed on the server
@@ -51,7 +64,7 @@
  *   1+       1       number of spectators on the server
  *   1 & 2    2       current game date in days since 1-1-1920 (DMY)
  *   1 & 2    2       game introduction date in days since 1-1-1920 (DMY)
- *   1+       var     string with the name of the map
+ *   1 - 5    var     string with the name of the map
  *   1+       2       width of the map in tiles
  *   1+       2       height of the map in tiles
  *   1+       1       type of map:
@@ -59,6 +72,13 @@
  *   1+       1       whether the server is dedicated (0 = no, 1 = yes)
  */
 
+/** The different types/ways a NewGRF can be serialized in the GameInfo since version 6. */
+enum NewGRFSerializationType {
+	NST_GRFID_MD5      = 0, ///< Unique GRF ID and MD5 checksum.
+	NST_GRFID_MD5_NAME = 1, ///< Unique GRF ID, MD5 checksum and name.
+	NST_END                 ///< The end of the list (period).
+};
+
 /**
  * The game information that is sent from the server to the client.
  */
@@ -92,6 +112,15 @@ struct NetworkGameInfo : NetworkServerGameInfo {
 	bool compatible;                                ///< Can we connect to this server or not? (based on server_revision _and_ grf_match
 };
 
+/**
+ * Container to hold the GRF identifier (GRF ID + MD5 checksum) and the name
+ * associated with that NewGRF.
+ */
+struct NamedGRFIdentifier {
+	GRFIdentifier ident; ///< The unique identifier of the NewGRF.
+	std::string name;    ///< The name of the NewGRF.
+};
+
 extern NetworkServerGameInfo _network_game_info;
 
 std::string_view GetNetworkRevisionString();
@@ -102,9 +131,10 @@ void FillStaticNetworkServerGameInfo();
 const NetworkServerGameInfo *GetCurrentNetworkServerGameInfo();
 
 void DeserializeGRFIdentifier(Packet *p, GRFIdentifier *grf);
+void DeserializeGRFIdentifierWithName(Packet *p, NamedGRFIdentifier *grf);
 void SerializeGRFIdentifier(Packet *p, const GRFIdentifier *grf);
 
 void DeserializeNetworkGameInfo(Packet *p, NetworkGameInfo *info);
-void SerializeNetworkGameInfo(Packet *p, const NetworkServerGameInfo *info);
+void SerializeNetworkGameInfo(Packet *p, const NetworkServerGameInfo *info, bool send_newgrf_names = true);
 
 #endif /* NETWORK_CORE_GAME_INFO_H */