Memory leak?

[joncrangle]

Howdy! I was using your crate to send mach messages with system stats to Sketchybar (Simple Sketchybar System Stats). I noticed that over time, the memory usage kept slowly growing.

I believe the main culprit is that the response pointer isn't freed after each message:

let result = unsafe {
        CStr::from_ptr(sketchybar(command.into_raw(), bar_name.into_raw()))
            .to_string_lossy()
            .into_owned()
    };

    Ok(result)

However, I'm no Rust or C expert (this is my first app using either language), so I iterated and tried different solutions to reduce the memory and port usage in my own implementation.

I ended up adding a C function to sketchybar.h to call from the Rust side to free the response pointer:

void free_sketchybar_response(char *response) { free(response); }

I don't know if you've noticed a similar issue with memory usage, but I'm sharing my implementation in case it's helpful:

sketchybar.rs
sketchybar.h

Some of my modifications are specific to my use case (I'm sending lots of messages, however I'm not expecting to receive messages), and I wanted to refresh the mach ports periodically because I had an issue with stale response ports not always being deallocated, so my function is async. I also haave a cleanup function in case my app is stopped but Sketchybar continues running.

[johnallen3d]

I think you're on to something @joncrangle! 😂

I'll incorporate your free_sketchybar_response function. Thanks!