deno/ext/napi/function.rs
2024-07-24 02:11:38 +02:00

96 lines
2.5 KiB
Rust

// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.
use crate::*;
#[repr(C)]
#[derive(Debug)]
pub struct CallbackInfo {
pub env: *mut Env,
pub cb: napi_callback,
pub cb_info: napi_callback_info,
pub args: *const c_void,
}
impl CallbackInfo {
#[inline]
pub fn new_raw(
env: *mut Env,
cb: napi_callback,
cb_info: napi_callback_info,
) -> *mut Self {
Box::into_raw(Box::new(Self {
env,
cb,
cb_info,
args: std::ptr::null(),
}))
}
}
extern "C" fn call_fn(info: *const v8::FunctionCallbackInfo) {
let callback_info = unsafe { &*info };
let args =
v8::FunctionCallbackArguments::from_function_callback_info(callback_info);
let mut rv = v8::ReturnValue::from_function_callback_info(callback_info);
// SAFETY: create_function guarantees that the data is a CallbackInfo external.
let info_ptr: *mut CallbackInfo = unsafe {
let external_value = v8::Local::<v8::External>::cast_unchecked(args.data());
external_value.value() as _
};
// SAFETY: pointer from Box::into_raw.
let info = unsafe { &mut *info_ptr };
info.args = &args as *const _ as *const c_void;
// SAFETY: calling user provided function pointer.
let value = unsafe { (info.cb)(info.env as napi_env, info_ptr as *mut _) };
if let Some(exc) = unsafe { &mut *info.env }.last_exception.take() {
let scope = unsafe { &mut v8::CallbackScope::new(callback_info) };
let exc = v8::Local::new(scope, exc);
scope.throw_exception(exc);
}
if let Some(value) = *value {
rv.set(value);
}
}
pub fn create_function<'s>(
scope: &mut v8::HandleScope<'s>,
env: *mut Env,
name: Option<v8::Local<v8::String>>,
cb: napi_callback,
cb_info: napi_callback_info,
) -> v8::Local<'s, v8::Function> {
let external =
v8::External::new(scope, CallbackInfo::new_raw(env, cb, cb_info) as *mut _);
let function = v8::Function::builder_raw(call_fn)
.data(external.into())
.build(scope)
.unwrap();
if let Some(v8str) = name {
function.set_name(v8str);
}
function
}
pub fn create_function_template<'s>(
scope: &mut v8::HandleScope<'s>,
env: *mut Env,
name: Option<v8::Local<v8::String>>,
cb: napi_callback,
cb_info: napi_callback_info,
) -> v8::Local<'s, v8::FunctionTemplate> {
let external =
v8::External::new(scope, CallbackInfo::new_raw(env, cb, cb_info) as *mut _);
let function = v8::FunctionTemplate::builder_raw(call_fn)
.data(external.into())
.build(scope);
if let Some(v8str) = name {
function.set_class_name(v8str);
}
function
}