#javascript-engine #bindings #hermes #libhermesabi

yanked libhermesabi-sys

Bindgen bindings for Hermes JavaScript engine

2 releases

0.1.1 Feb 26, 2024
0.1.0 Feb 26, 2024

#48 in #javascript-engine

33 downloads per month
Used in rusty_hermes

MIT license

6KB

libhermesabi-sys

Note: Currently only supports on Linux and macOS. Adding Windows support should be trivial.

This crate contains bindgen-generated Rust bindings for Hermes C ABI.

Requirements

Before building Hermes, install the required dependencies:

Ubuntu

apt install cmake git ninja-build libicu-dev python zip libreadline-dev

Arch

pacman -S cmake git ninja icu python zip readline

macOS via Homebrew

brew install cmake git ninja

Examples

use libhermesabi_sys::*;
use std::ffi::CString;

unsafe extern "C" fn release_wrapper(_buf: *mut HermesABIBuffer) {}

fn main() {
    unsafe {
        let vtable_ptr = get_hermes_abi_vtable();
        let vtable = &*vtable_ptr;

        let config = std::ptr::null();
        let runtime_ptr = (vtable.make_hermes_runtime.unwrap())(config);

        let runtime = &*runtime_ptr;
        let runtime_vt = &*runtime.vt;

        let script = String::from("x = 1 + 2");
        let script_url = CString::new("./src/test.js").expect("CString::new failed");

        let vtable = HermesABIBufferVTable {
            release: Some(release_wrapper),
        };

        let mut x = HermesABIBuffer {
            vtable: &vtable,
            data: script.as_ptr(),
            size: script.len(),
        };

        let buffer_ptr = &mut x as *mut HermesABIBuffer;

        let eval = runtime_vt.evaluate_javascript_source.unwrap();
        let v = eval(
            runtime_ptr,
            buffer_ptr,
            script_url.as_ptr(),
            script_url.as_bytes().len(),
        );

        assert_eq!(v.value.data.number, 3.0);
    }
}

No runtime deps

~0–2MB
~40K SLoC