A symbol map is a description of what variables and functions exist
where in compiled code they are. GameCube and Wii games are written in C, compiled to PowerPC assembly code,
and stored in a .dol file. The .dol file does not include a symbol map,
and therefore we do not know where certain variables and functions are, nor what their names are.
Instead of using an official symbol map, we have community symbol maps. These are symbol maps that are
created from the ground-up using inference about what specific code does. You can find the current community
symbol maps under general/symbol_maps.
Each symbol map is named after its respective Game ID
and ending with .map.
First, figure out if there is already a community symbol map for your game. If we look at
Game IDs, we can see that
Naruto GNT4
uses the Game ID G4NJDA, so we should download G4NJDA.map. Once you open the community
symbol map on Github, here for GNT4 for example,
right click on the Raw button and select Save Link As... to save it somewhere.
Now in Dolphin, go to File->Open User Folder. If you are on an older version of Dolphin and don't have this setting, use Windows Explorer to navigate to C:\Users{your user}\Documents\Dolphin Emulator
Once you have it open, then open the Maps folder and put your symbol map file in it.
Now back in Dolphin, start up your game and it should load the symbol map automatically.
You can be 100% it is loaded by doing so manually by going to Symbols->Load Symbol Map
To actually see the symbols, you'll need to enable the Code view on Dolphin. Right click on the grey bar below the Dolphin controls and select Code.
Now in the code view, you can see the known function names and locations under Symbols as well as the current code being called under Callstack. These both are highlighted in red below. Read more info on Callstacks here.
Make sure you follow the Ghidra Guide first to make sure Ghidra is set up correctly.
It is generally preferred to use a community Ghidra Zip File instead of a symbol map in Ghidra. That is because the Ghidra Zip File contains more game information than a symbol map does. Community Ghidra Zip Files cannot be directly linked here due to containing the code of the game.
Assuming you cannot get a Ghidra Zip File or none exists, find or
create a symbol map for your game. Then in Ghidra,
go to File->Import File and select the .dol file for your game. After you give it a
Program Name and hit OK it will ask for your Symbol Map. Hit Yes and select your symbol map.
Ghidra will use the symbol map to document functions and variables that it disassembles.
If a symbol map doesn't exist yet for a game, you first will need to create a starting map
from Dolphin. In Dolphin run the game and go to Symbols -> Generate Symbols From -> Signature Database.
Once that is complete go to Symbols -> Save Symbol Map.
You can find your new symbol map file in the Dolphin symbol map folder described in How to Use Symbol Maps in Dolphin.
When Dolphin generates a symbol map, it will examine the code and look for patterns similar to known GameCube/Wii SDK functions. Dolphin will almost certainly create many false positives, so you may see many instances of the same symbol. At this point the symbol map is usable, but you may want to use Ghidra to remove false positives and document other known functions.