Rust Bindings

Raw extern "C" declarations for cactus_engine.h.

Integration

cactus build

Copy cactus.rs into your project (it carries its own #[link] attributes) and point Cargo at the build directory:

// build.rs
println!("cargo:rustc-link-search=native=/path/to/cactus/cactus-engine/build");

Usage

use std::ffi::CString;
use std::os::raw::c_char;

mod cactus;

fn main() {
    unsafe {
        let path = CString::new("/path/to/model").unwrap();
        let model = cactus::cactus_init(path.as_ptr(), std::ptr::null(), false);

        let messages = CString::new(r#"[{"role":"user","content":"Hello"}]"#).unwrap();
        let mut response = vec![0u8; 65536];
        cactus::cactus_complete(
            model,
            messages.as_ptr(),
            response.as_mut_ptr() as *mut c_char,
            response.len(),
            std::ptr::null(), std::ptr::null(),
            None, std::ptr::null_mut(),
            std::ptr::null(), 0,
        );

        cactus::cactus_destroy(model);
    }
}

Streaming transcription

Push 16 kHz mono PCM16 as it arrives; each call returns {"success":true,"confirmed":...,"pending":...} (confirmed is final, pending is the volatile tail). All unsafe, like the rest:

let opts = CString::new(r#"{"language":"en"}"#).unwrap();
let stream = cactus::cactus_stream_transcribe_start(model, opts.as_ptr());
let mut buf = vec![0u8; 65536];
for chunk in pcm_chunks { // each: 16 kHz mono i16 bytes
    cactus::cactus_stream_transcribe_process(
        stream, chunk.as_ptr(), chunk.len(),
        buf.as_mut_ptr() as *mut c_char, buf.len(),
    );
    // append "confirmed"; show "pending" as a live preview
}
cactus::cactus_stream_transcribe_stop(stream, buf.as_mut_ptr() as *mut c_char, buf.len());