SNES - Playable-Quotes/QuoteKit GitHub Wiki
How do we launch Retroarch and attach Frida to it?
Find the current frida version with this command:
$ frida --version 16.2.1
Next, download corresponding gadget from the compiled releases on the frida github project: https://github.com/frida/frida/releases/
We want the file that looks like this “frida-gadget-{version}-macos-universal.dylib.xz”.
Download and unzip this file to recover the .dylib file.
Now, launch RetroArch with the frida gadget injected:
$ DYLD_INSERT_LIBRARIES=frida-gadget-16.2.1-macos-universal.dylib /Applications/RetroArch.app/Contents/MacOS/RetroArch -L snes9x_libretro /Users/adam/Downloads/Super\ Mario\ World\ (USA).sfc
[Frida INFO] Listening on 127.0.0.1 TCP port 27042
The RetroArch window will not display as frida has halted the app’s start up to give you a chance to attach frida first.
In another terminal window, launch frida with the “-R” flag to have it connect to a remote process (using localhost:27024 as the default remote configuration).
$ frida -R Gadget
…
. . . . Connected to Local Socket (id=socket)
The moment frida connects, RetroArch should finish launching!
How do we hook into the emulator's main loop?
Intercept calls to retro_run
const funcAddr = DebugSymbol.fromName("retro_run").address;
Interceptor.attach(funcAddr, function () {
...
});
How fast (Hz) does the main loop typically run?
60.6 Hz (on Tony's Macbook Air M2 2022)
What does it cost to create a savestate?
TODO: Measure the actual time spend saving the state (now that we know it is small enough not to disrupt the main loop much).
How do we replay user-input events over time?
TODO We should respect sub-tick time granularity if needed on that platform.
How do we get a pointer to the emulated system's main memory buffer and determine the size of the buffer?
We can call retro_get_memory_data"to get a pointer to the base and retro_get_memory_size to find the length.
For memory-like mass storage, how do we find out which blocks have been accessed since the last tick?
Can we just use Frida's MemoryAccessMonitor?
- Seems like MemoryAccessMonitor isn't fully implemented. There are mixed results with using it on windows, but with mixed results, so avoid it instead.