1use jrsonnet_evaluator::{error::Error, native::NativeCallback, EvaluationState, Val};2use jrsonnet_parser::{Param, ParamsDesc};3use std::{4 ffi::{c_void, CStr},5 os::raw::{c_char, c_int},6 rc::Rc,7};89type JsonnetNativeCallback = unsafe extern "C" fn(10 ctx: *const c_void,11 argv: *const *const Val,12 success: *mut c_int,13) -> *mut Val;141516#[no_mangle]17pub unsafe extern "C" fn jsonnet_native_callback(18 vm: &EvaluationState,19 name: *const c_char,20 cb: JsonnetNativeCallback,21 ctx: *const c_void,22 mut raw_params: *const *const c_char,23) {24 let name = CStr::from_ptr(name).to_str().expect("utf8 name").into();25 let mut params = Vec::new();26 loop {27 if (*raw_params).is_null() {28 break;29 }30 let param = CStr::from_ptr(*raw_params).to_str().expect("not utf8");31 params.push(Param(param.into(), None));32 raw_params = raw_params.offset(1);33 }34 let params = ParamsDesc(Rc::new(params));3536 vm.add_native(37 name,38 Rc::new(NativeCallback::new(params, move |args| {39 let mut n_args = Vec::new();40 for a in args {41 n_args.push(Some(Box::new(a.clone())));42 }43 n_args.push(None);44 let mut success = 1;45 let v = cb(ctx, &n_args as *const _ as *const *const Val, &mut success);46 let v = *Box::from_raw(v);47 if success == 1 {48 Ok(v)49 } else {50 let e = v.try_cast_str("native error").expect("error msg");51 Err(Error::RuntimeError(e).into())52 }53 })),54 )55}