port: load gamecontrollerdb if available

port/src/input.c

@@ -10,6 +10,9 @@
 #include "config.h"
 #include "utils.h"
 #include "system.h"
+#include "fs.h"
+
+#define CONTROLLERDB_FNAME "gamecontrollerdb.txt"
 
 #define MAX_BIND_STR 256
 
@@ -637,6 +640,15 @@ s32 inputInit(void)
 		SDL_InitSubSystem(SDL_INIT_GAMECONTROLLER | SDL_INIT_HAPTIC);
 	}
 
+	// try to load controller db from an external file in the save folder
+	if (fsFileSize("$S/" CONTROLLERDB_FNAME)) {
+		const char *dbpath = fsFullPath("$S/" CONTROLLERDB_FNAME);
+		const s32 dbcount = SDL_GameControllerAddMappingsFromFile(dbpath);
+		if (dbcount >= 0) {
+			sysLogPrintf(LOG_NOTE, "input: added %d controller mappings from %s", dbcount, dbpath);
+		}
+	}
+
 	inputInitAllControllers();
 
 	// since the main event loop is elsewhere, we can receive some events we need using a watcher