Add Debugging with Ghidra on Linux

Debugging-with-Ghidra-on-Linux.md

@@ -0,0 +1,27 @@
+> To be fleshed out, for now this is just me dumping steps as I do them
+
+1. Open the `darktide_launcher.log` and find the arguments to run the executable with.
+
+    At the time of writing: `-eac-untrusted --bundle-dir ../bundle --ini settings --backend-auth-service-url https://bsp-auth-prod.atoma.cloud --backend-title-service-url https://bsp-td-prod.atoma.cloud -game -launcher_verification_passed_crashify_property false`
+    
+2. Find the necessary env variables and commands to run Proton from CLI.
+    At the time of writing:
+
+```bash
+STEAM_COMPAT_CLIENT_INSTALL_PATH=/usr/bin/steam
+# `1361210` is the Steam AppID for Darktide. It's in the same library as the game, so through "Browse files" in the UI works as starting point
+STEAM_COMPAT_DATA_PATH=/path/to/SteamLibrary/steamapps/compatdata/1361210
+# Any Proton version could be used, if it works with the game.
+# And it's fine if this is installed in a different `SteamLibrary` than the game
+/path/to/SteamLibrary/steamapps/common/Proton\ 8.0/proton run <cmd>
+```
+
+3. Add `PROTON_DUMP_DEBUG_COMMANDS=1`, then look in `/tmp/proton_$(whoami)`
+4. Copy `gdb_run`, and alter the `winedbg` command with `s/--dbg/--dbg --no-start --port 2159/` (or a port of your choosing).
+    Worthwhile to have it as separate file `gdb_start`, so that `gdb_run` stays available.
+
+    `--no-start` will make gdb wait for the frontend to send the first `continue` command, which gives time to attach Ghidra and have it set up its breakpoints
+
+5. Run the script in a terminal, a black window should appear
+6. In Ghidra, for the debugger configuration, choose "remote gdb", enter the port and run. Breakpoints should become available
+7. Run `continue` (or just `c`) in the gdb terminal, or any other gdb command.