Add: support filtering content entries for patchpacks (#9541)

This changes nothing for us, but allows patchpacks to add the
right pieces of code to start filtering content entries on patchpack
only entries.

src/network/core/tcp_content.h

@@ -26,7 +26,11 @@ protected:
 	/**
 	 * Client requesting a list of content info:
 	 *  byte    type
-	 *  uint32  openttd version
+	 *  uint32  openttd version (or 0xFFFFFFFF if using a list)
+	 * Only if the above value is 0xFFFFFFFF:
+	 *  uint8   count
+	 *  string  branch-name ("vanilla" for upstream OpenTTD)
+	 *  string  release version (like "12.0")
 	 * @param p The packet that was just received.
 	 * @return True upon success, otherwise false.
 	 */

src/network/network_content.cpp

@@ -207,7 +207,20 @@ void ClientNetworkContentSocketHandler::RequestContentList(ContentType type)
 
 	Packet *p = new Packet(PACKET_CONTENT_CLIENT_INFO_LIST);
 	p->Send_uint8 ((byte)type);
-	p->Send_uint32(_openttd_newgrf_version);
+	p->Send_uint32(0xffffffff);
+	p->Send_uint8 (1);
+	p->Send_string("vanilla");
+	p->Send_string(_openttd_content_version);
+
+	/* Patchpacks can extend the list with one. In BaNaNaS metadata you can
+	 * add a branch in the 'compatibility' list, to filter on this. If you want
+	 * your patchpack to be mentioned in the BaNaNaS web-interface, create an
+	 * issue on https://github.com/OpenTTD/bananas-api asking for this.
+
+	p->Send_string("patchpack"); // Or what-ever the name of your patchpack is.
+	p->Send_string(_openttd_content_version_patchpack);
+
+	*/
 
 	this->SendPacket(p);
 }

src/rev.cpp.in

@@ -72,6 +72,13 @@ const byte _openttd_revision_modified = ${REV_MODIFIED};
  */
 const byte _openttd_revision_tagged = ${REV_ISTAG};
 
+/**
+ * To check compatibility of BaNaNaS content, this version string is used.
+ * It should never contain things like "beta", but only the release version
+ * we are compatible with.
+ */
+const char _openttd_content_version[] = "${REV_MAJOR}.${REV_MINOR}";
+
 /**
  * The NewGRF revision of OTTD:
  * bits  meaning.

src/rev.h

@@ -16,6 +16,7 @@ extern const char _openttd_revision_hash[];
 extern const char _openttd_revision_year[];
 extern const byte _openttd_revision_modified;
 extern const byte _openttd_revision_tagged;
+extern const char _openttd_content_version[];
 extern const uint32 _openttd_newgrf_version;
 
 bool IsReleasedVersion();