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Copy pathscope.rs
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950 lines (871 loc) · 38.7 KB
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use std::any::Any;
use std::cell::{Cell, RefCell};
use std::marker::PhantomData;
use std::mem;
use std::os::raw::c_int;
#[cfg(feature = "serialize")]
use serde::Serialize;
use crate::error::{Error, Result};
use crate::function::Function;
use crate::lua::Lua;
use crate::types::{Callback, CallbackUpvalue, LuaRef, MaybeSend, SubtypeId};
use crate::userdata::{
AnyUserData, MetaMethod, UserData, UserDataCell, UserDataFields, UserDataMethods,
};
use crate::userdata_impl::UserDataRegistry;
use crate::util::{
self, assert_stack, check_stack, init_userdata_metatable, push_string, push_table,
rawset_field, short_type_name, take_userdata, StackGuard,
};
use crate::value::{FromLua, FromLuaMulti, IntoLua, IntoLuaMulti};
#[cfg(feature = "lua54")]
use crate::userdata::USER_VALUE_MAXSLOT;
#[cfg(feature = "async")]
use std::future::Future;
/// Constructed by the [`Lua::scope`] method, allows temporarily creating Lua userdata and
/// callbacks that are not required to be Send or 'static.
///
/// See [`Lua::scope`] for more details.
///
/// [`Lua::scope`]: crate::Lua.html::scope
pub struct Scope<'lua, 'scope>
where
'lua: 'scope,
{
lua: &'lua Lua,
destructors: RefCell<Vec<(LuaRef<'lua>, DestructorCallback<'lua>)>>,
_scope_invariant: PhantomData<Cell<&'scope ()>>,
}
type DestructorCallback<'lua> = Box<dyn Fn(LuaRef<'lua>) -> Vec<Box<dyn Any>> + 'lua>;
impl<'lua, 'scope> Scope<'lua, 'scope> {
pub(crate) fn new(lua: &'lua Lua) -> Scope<'lua, 'scope> {
Scope {
lua,
destructors: RefCell::new(Vec::new()),
_scope_invariant: PhantomData,
}
}
/// Wraps a Rust function or closure, creating a callable Lua function handle to it.
///
/// This is a version of [`Lua::create_function`] that creates a callback which expires on
/// scope drop. See [`Lua::scope`] for more details.
///
/// [`Lua::create_function`]: crate::Lua::create_function
/// [`Lua::scope`]: crate::Lua::scope
pub fn create_function<'callback, A, R, F>(&'callback self, func: F) -> Result<Function<'lua>>
where
A: FromLuaMulti<'callback>,
R: IntoLuaMulti<'callback>,
F: Fn(&'callback Lua, A) -> Result<R> + 'scope,
{
// Safe, because 'scope must outlive 'callback (due to Self containing 'scope), however the
// callback itself must be 'scope lifetime, so the function should not be able to capture
// anything of 'callback lifetime. 'scope can't be shortened due to being invariant, and
// the 'callback lifetime here can't be enlarged due to coming from a universal
// quantification in Lua::scope.
//
// I hope I got this explanation right, but in any case this is tested with compiletest_rs
// to make sure callbacks can't capture handles with lifetime outside the scope, inside the
// scope, and owned inside the callback itself.
unsafe {
self.create_callback(Box::new(move |lua, nargs| {
let args = A::from_stack_args(nargs, 1, None, lua)?;
func(lua, args)?.push_into_stack_multi(lua)
}))
}
}
/// Wraps a Rust mutable closure, creating a callable Lua function handle to it.
///
/// This is a version of [`Lua::create_function_mut`] that creates a callback which expires
/// on scope drop. See [`Lua::scope`] and [`Scope::create_function`] for more details.
///
/// [`Lua::create_function_mut`]: crate::Lua::create_function_mut
/// [`Lua::scope`]: crate::Lua::scope
/// [`Scope::create_function`]: #method.create_function
pub fn create_function_mut<'callback, A, R, F>(
&'callback self,
func: F,
) -> Result<Function<'lua>>
where
A: FromLuaMulti<'callback>,
R: IntoLuaMulti<'callback>,
F: FnMut(&'callback Lua, A) -> Result<R> + 'scope,
{
let func = RefCell::new(func);
self.create_function(move |lua, args| {
(*func
.try_borrow_mut()
.map_err(|_| Error::RecursiveMutCallback)?)(lua, args)
})
}
/// Creates a Lua userdata object from a custom userdata type.
///
/// This is a version of [`Lua::create_userdata`] that creates a userdata which expires on
/// scope drop, and does not require that the userdata type be Send (but still requires that the
/// UserData be 'static).
/// See [`Lua::scope`] for more details.
///
/// [`Lua::create_userdata`]: crate::Lua::create_userdata
/// [`Lua::scope`]: crate::Lua::scope
pub fn create_userdata<T>(&self, data: T) -> Result<AnyUserData<'lua>>
where
T: UserData + 'static,
{
// Safe even though T may not be Send, because the parent Lua cannot be sent to another
// thread while the Scope is alive (or the returned AnyUserData handle even).
unsafe {
let ud = self.lua.make_userdata(UserDataCell::new(data))?;
self.seal_userdata::<T>(&ud)?;
Ok(ud)
}
}
/// Creates a Lua userdata object from a custom serializable userdata type.
///
/// This is a version of [`Lua::create_ser_userdata`] that creates a userdata which expires on
/// scope drop, and does not require that the userdata type be Send (but still requires that the
/// UserData be 'static).
/// See [`Lua::scope`] for more details.
///
/// Requires `feature = "serialize"`
///
/// [`Lua::create_ser_userdata`]: crate::Lua::create_ser_userdata
/// [`Lua::scope`]: crate::Lua::scope
#[cfg(feature = "serialize")]
#[cfg_attr(docsrs, doc(cfg(feature = "serialize")))]
pub fn create_ser_userdata<T>(&self, data: T) -> Result<AnyUserData<'lua>>
where
T: UserData + Serialize + 'static,
{
unsafe {
let ud = self.lua.make_userdata(UserDataCell::new_ser(data))?;
self.seal_userdata::<T>(&ud)?;
Ok(ud)
}
}
/// Creates a Lua userdata object from a reference to custom userdata type.
///
/// This is a version of [`Lua::create_userdata`] that creates a userdata which expires on
/// scope drop, and does not require that the userdata type be Send. This method takes non-'static
/// reference to the data. See [`Lua::scope`] for more details.
///
/// Userdata created with this method will not be able to be mutated from Lua.
pub fn create_userdata_ref<T>(&self, data: &'scope T) -> Result<AnyUserData<'lua>>
where
T: UserData + 'static,
{
unsafe {
let ud = self.lua.make_userdata(UserDataCell::new_ref(data))?;
self.seal_userdata::<T>(&ud)?;
Ok(ud)
}
}
/// Creates a Lua userdata object from a mutable reference to custom userdata type.
///
/// This is a version of [`Lua::create_userdata`] that creates a userdata which expires on
/// scope drop, and does not require that the userdata type be Send. This method takes non-'static
/// mutable reference to the data. See [`Lua::scope`] for more details.
pub fn create_userdata_ref_mut<T>(&self, data: &'scope mut T) -> Result<AnyUserData<'lua>>
where
T: UserData + 'static,
{
unsafe {
let ud = self.lua.make_userdata(UserDataCell::new_ref_mut(data))?;
self.seal_userdata::<T>(&ud)?;
Ok(ud)
}
}
/// Creates a Lua userdata object from a custom Rust type.
///
/// This is a version of [`Lua::create_any_userdata`] that creates a userdata which expires on
/// scope drop and does not require that the userdata type be Send (but still requires that the
/// UserData be 'static). See [`Lua::scope`] for more details.
#[inline]
pub fn create_any_userdata<T>(&self, data: T) -> Result<AnyUserData<'lua>>
where
T: 'static,
{
unsafe {
let ud = self.lua.make_any_userdata(UserDataCell::new(data))?;
self.seal_userdata::<T>(&ud)?;
Ok(ud)
}
}
/// Creates a Lua userdata object from a reference to custom Rust type.
///
/// This is a version of [`Lua::create_any_userdata`] that creates a userdata which expires on
/// scope drop, and does not require that the Rust type be Send. This method takes non-'static
/// reference to the data. See [`Lua::scope`] for more details.
///
/// Userdata created with this method will not be able to be mutated from Lua.
pub fn create_any_userdata_ref<T>(&self, data: &'scope T) -> Result<AnyUserData<'lua>>
where
T: 'static,
{
unsafe {
let ud = self.lua.make_any_userdata(UserDataCell::new_ref(data))?;
self.seal_userdata::<T>(&ud)?;
Ok(ud)
}
}
/// Creates a Lua userdata object from a mutable reference to custom Rust type.
///
/// This is a version of [`Lua::create_any_userdata`] that creates a userdata which expires on
/// scope drop, and does not require that the Rust type be Send. This method takes non-'static
/// mutable reference to the data. See [`Lua::scope`] for more details.
pub fn create_any_userdata_ref_mut<T>(&self, data: &'scope mut T) -> Result<AnyUserData<'lua>>
where
T: 'static,
{
let lua = self.lua;
unsafe {
let ud = lua.make_any_userdata(UserDataCell::new_ref_mut(data))?;
self.seal_userdata::<T>(&ud)?;
Ok(ud)
}
}
/// Shortens the lifetime of a userdata to the lifetime of the scope.
unsafe fn seal_userdata<T: 'static>(&self, ud: &AnyUserData<'lua>) -> Result<()> {
#[cfg(any(feature = "lua51", feature = "luajit"))]
let newtable = self.lua.create_table()?;
let destructor: DestructorCallback = Box::new(move |ud| {
let state = ud.lua.state();
let _sg = StackGuard::new(state);
assert_stack(state, 2);
// Check that userdata is not destructed (via `take()` call)
if ud.lua.push_userdata_ref(&ud).is_err() {
return vec![];
}
// Clear associated user values
#[cfg(feature = "lua54")]
for i in 1..=USER_VALUE_MAXSLOT {
ffi::lua_pushnil(state);
ffi::lua_setiuservalue(state, -2, i as _);
}
#[cfg(any(feature = "lua53", feature = "lua52", feature = "luau"))]
{
ffi::lua_pushnil(state);
ffi::lua_setuservalue(state, -2);
}
#[cfg(any(feature = "lua51", feature = "luajit"))]
{
ud.lua.push_ref(&newtable.0);
ffi::lua_setuservalue(state, -2);
}
vec![Box::new(take_userdata::<UserDataCell<T>>(state))]
});
self.destructors
.borrow_mut()
.push((ud.0.clone(), destructor));
Ok(())
}
/// Creates a Lua userdata object from a custom userdata type.
///
/// This is a version of [`Lua::create_userdata`] that creates a userdata which expires on
/// scope drop, and does not require that the userdata type be Send or 'static. See
/// [`Lua::scope`] for more details.
///
/// Lifting the requirement that the UserData type be 'static comes with some important
/// limitations, so if you only need to eliminate the Send requirement, it is probably better to
/// use [`Scope::create_userdata`] instead.
///
/// The main limitation that comes from using non-'static userdata is that the produced userdata
/// will no longer have a `TypeId` associated with it, because `TypeId` can only work for
/// 'static types. This means that it is impossible, once the userdata is created, to get a
/// reference to it back *out* of an `AnyUserData` handle. This also implies that the
/// "function" type methods that can be added via [`UserDataMethods`] (the ones that accept
/// `AnyUserData` as a first parameter) are vastly less useful. Also, there is no way to re-use
/// a single metatable for multiple non-'static types, so there is a higher cost associated with
/// creating the userdata metatable each time a new userdata is created.
///
/// [`Scope::create_userdata`]: #method.create_userdata
/// [`Lua::create_userdata`]: crate::Lua::create_userdata
/// [`Lua::scope`]:crate::Lua::scope
/// [`UserDataMethods`]: crate::UserDataMethods
pub fn create_nonstatic_userdata<T>(&self, data: T) -> Result<AnyUserData<'lua>>
where
T: UserData + 'scope,
{
// 'callback outliving 'scope is a lie to make the types work out, required due to the
// inability to work with the more correct callback type that is universally quantified over
// 'lua. This is safe though, because `UserData::add_methods` does not get to pick the 'lua
// lifetime, so none of the static methods UserData types can add can possibly capture
// parameters.
unsafe fn wrap_method<'scope, 'lua, 'callback: 'scope, T: 'scope>(
scope: &Scope<'lua, 'scope>,
ud_ptr: *const UserDataCell<T>,
name: &str,
method: NonStaticMethod<'callback, T>,
) -> Result<Function<'lua>> {
// On methods that actually receive the userdata, we fake a type check on the passed in
// userdata, where we pretend there is a unique type per call to
// `Scope::create_nonstatic_userdata`. You can grab a method from a userdata and call
// it on a mismatched userdata type, which when using normal 'static userdata will fail
// with a type mismatch, but here without this check would proceed as though you had
// called the method on the original value (since we otherwise completely ignore the
// first argument).
let func_name = format!("{}.{name}", short_type_name::<T>());
let check_self_type = move |lua: &Lua, nargs: c_int| -> Result<&UserDataCell<T>> {
let state = lua.state();
if nargs > 0 && ffi::lua_touserdata(state, -nargs) as *const _ == ud_ptr {
return Ok(&*ud_ptr);
}
Err(Error::bad_self_argument(
&func_name,
Error::UserDataTypeMismatch,
))
};
match method {
NonStaticMethod::Method(method) => {
let f = Box::new(move |lua, nargs| {
let data = check_self_type(lua, nargs)?;
let data = data.try_borrow()?;
method(lua, &*data, nargs - 1)
});
scope.create_callback(f)
}
NonStaticMethod::MethodMut(method) => {
let method = RefCell::new(method);
let f = Box::new(move |lua, nargs| {
let data = check_self_type(lua, nargs)?;
let mut method = method
.try_borrow_mut()
.map_err(|_| Error::RecursiveMutCallback)?;
let mut data = data.try_borrow_mut()?;
(*method)(lua, &mut *data, nargs - 1)
});
scope.create_callback(f)
}
NonStaticMethod::Function(function) => scope.create_callback(function),
NonStaticMethod::FunctionMut(function) => {
let function = RefCell::new(function);
let f = Box::new(move |lua, nargs| {
let mut func = function
.try_borrow_mut()
.map_err(|_| Error::RecursiveMutCallback)?;
func(lua, nargs)
});
scope.create_callback(f)
}
}
}
let mut registry = NonStaticUserDataRegistry::new();
T::add_fields(&mut registry);
T::add_methods(&mut registry);
let lua = self.lua;
let state = lua.state();
unsafe {
let _sg = StackGuard::new(state);
check_stack(state, 13)?;
#[cfg(not(feature = "luau"))]
let ud_ptr = protect_lua!(state, 0, 1, |state| {
let ud = ffi::lua_newuserdata(state, mem::size_of::<UserDataCell<T>>());
// Set empty environment for Lua 5.1
#[cfg(any(feature = "lua51", feature = "luajit"))]
{
ffi::lua_newtable(state);
ffi::lua_setuservalue(state, -2);
}
ud as *const UserDataCell<T>
})?;
#[cfg(feature = "luau")]
let ud_ptr = {
util::push_userdata(state, UserDataCell::new(data), true)?;
ffi::lua_touserdata(state, -1) as *const UserDataCell<T>
};
// Prepare metatable, add meta methods first and then meta fields
let meta_methods_nrec = registry.meta_methods.len() + registry.meta_fields.len() + 1;
push_table(state, 0, meta_methods_nrec, true)?;
for (k, m) in registry.meta_methods {
lua.push(wrap_method(self, ud_ptr, &k, m)?)?;
rawset_field(state, -2, MetaMethod::validate(&k)?)?;
}
let mut has_name = false;
for (k, f) in registry.meta_fields {
has_name = has_name || k == MetaMethod::Type;
mlua_assert!(f(lua, 0)? == 1, "field function must return one value");
rawset_field(state, -2, MetaMethod::validate(&k)?)?;
}
// Set `__name/__type` if not provided
if !has_name {
let type_name = short_type_name::<T>();
push_string(state, type_name.as_bytes(), !lua.unlikely_memory_error())?;
rawset_field(state, -2, MetaMethod::Type.name())?;
}
let metatable_index = ffi::lua_absindex(state, -1);
let fields_nrec = registry.fields.len();
if fields_nrec > 0 {
// If __index is a table then update it inplace
let index_type = ffi::lua_getfield(state, metatable_index, cstr!("__index"));
match index_type {
ffi::LUA_TNIL | ffi::LUA_TTABLE => {
if index_type == ffi::LUA_TNIL {
// Create a new table
ffi::lua_pop(state, 1);
push_table(state, 0, fields_nrec, true)?;
}
for (k, f) in registry.fields {
#[rustfmt::skip]
let NonStaticMethod::Function(f) = f else { unreachable!() };
mlua_assert!(f(lua, 0)? == 1, "field function must return one value");
rawset_field(state, -2, &k)?;
}
rawset_field(state, metatable_index, "__index")?;
}
_ => {
// Propagate fields to the field getters
for (k, f) in registry.fields {
registry.field_getters.push((k, f))
}
}
}
}
let mut field_getters_index = None;
let field_getters_nrec = registry.field_getters.len();
if field_getters_nrec > 0 {
push_table(state, 0, field_getters_nrec, true)?;
for (k, m) in registry.field_getters {
lua.push(wrap_method(self, ud_ptr, &k, m)?)?;
rawset_field(state, -2, &k)?;
}
field_getters_index = Some(ffi::lua_absindex(state, -1));
}
let mut field_setters_index = None;
let field_setters_nrec = registry.field_setters.len();
if field_setters_nrec > 0 {
push_table(state, 0, field_setters_nrec, true)?;
for (k, m) in registry.field_setters {
lua.push(wrap_method(self, ud_ptr, &k, m)?)?;
rawset_field(state, -2, &k)?;
}
field_setters_index = Some(ffi::lua_absindex(state, -1));
}
let mut methods_index = None;
let methods_nrec = registry.methods.len();
if methods_nrec > 0 {
// Create table used for methods lookup
push_table(state, 0, methods_nrec, true)?;
for (k, m) in registry.methods {
lua.push(wrap_method(self, ud_ptr, &k, m)?)?;
rawset_field(state, -2, &k)?;
}
methods_index = Some(ffi::lua_absindex(state, -1));
}
#[cfg(feature = "luau")]
let extra_init = None;
#[cfg(not(feature = "luau"))]
let extra_init: Option<fn(*mut ffi::lua_State) -> Result<()>> = Some(|state| {
ffi::lua_pushcfunction(state, util::userdata_destructor::<UserDataCell<T>>);
rawset_field(state, -2, "__gc")
});
init_userdata_metatable(
state,
metatable_index,
field_getters_index,
field_setters_index,
methods_index,
extra_init,
)?;
let count = field_getters_index.map(|_| 1).unwrap_or(0)
+ field_setters_index.map(|_| 1).unwrap_or(0)
+ methods_index.map(|_| 1).unwrap_or(0);
ffi::lua_pop(state, count);
let mt_ptr = ffi::lua_topointer(state, -1);
// Write userdata just before attaching metatable with `__gc` metamethod
#[cfg(not(feature = "luau"))]
std::ptr::write(ud_ptr as _, UserDataCell::new(data));
ffi::lua_setmetatable(state, -2);
let ud = AnyUserData(lua.pop_ref(), SubtypeId::None);
lua.register_raw_userdata_metatable(mt_ptr, None);
#[cfg(any(feature = "lua51", feature = "luajit"))]
let newtable = lua.create_table()?;
let destructor: DestructorCallback = Box::new(move |ud| {
let state = ud.lua.state();
let _sg = StackGuard::new(state);
assert_stack(state, 2);
// Check that userdata is valid (very likely)
if ud.lua.push_userdata_ref(&ud).is_err() {
return vec![];
}
// Deregister metatable
ffi::lua_getmetatable(state, -1);
let mt_ptr = ffi::lua_topointer(state, -1);
ffi::lua_pop(state, 1);
ud.lua.deregister_raw_userdata_metatable(mt_ptr);
// Clear associated user values
#[cfg(feature = "lua54")]
for i in 1..=USER_VALUE_MAXSLOT {
ffi::lua_pushnil(state);
ffi::lua_setiuservalue(state, -2, i as _);
}
#[cfg(any(feature = "lua53", feature = "lua52", feature = "luau"))]
{
ffi::lua_pushnil(state);
ffi::lua_setuservalue(state, -2);
}
#[cfg(any(feature = "lua51", feature = "luajit"))]
{
ud.lua.push_ref(&newtable.0);
ffi::lua_setuservalue(state, -2);
}
// A hack to drop non-static `T`
unsafe fn seal<T>(t: T) -> Box<dyn FnOnce() + 'static> {
let f: Box<dyn FnOnce()> = Box::new(move || drop(t));
mem::transmute(f)
}
let ud = take_userdata::<UserDataCell<T>>(state);
vec![Box::new(seal(ud))]
});
self.destructors
.borrow_mut()
.push((ud.0.clone(), destructor));
Ok(ud)
}
}
// Unsafe, because the callback can improperly capture any value with 'callback scope, such as
// improperly capturing an argument. Since the 'callback lifetime is chosen by the user and the
// lifetime of the callback itself is 'scope (non-'static), the borrow checker will happily pick
// a 'callback that outlives 'scope to allow this. In order for this to be safe, the callback
// must NOT capture any parameters.
unsafe fn create_callback<'callback>(
&self,
f: Callback<'callback, 'scope>,
) -> Result<Function<'lua>> {
let f = mem::transmute::<Callback<'callback, 'scope>, Callback<'lua, 'static>>(f);
let f = self.lua.create_callback(f)?;
let destructor: DestructorCallback = Box::new(|f| {
let state = f.lua.state();
let _sg = StackGuard::new(state);
assert_stack(state, 3);
f.lua.push_ref(&f);
// We know the destructor has not run yet because we hold a reference to the callback.
ffi::lua_getupvalue(state, -1, 1);
let ud = take_userdata::<CallbackUpvalue>(state);
ffi::lua_pushnil(state);
ffi::lua_setupvalue(state, -2, 1);
vec![Box::new(ud)]
});
self.destructors
.borrow_mut()
.push((f.0.clone(), destructor));
Ok(f)
}
}
impl<'lua, 'scope> Drop for Scope<'lua, 'scope> {
fn drop(&mut self) {
// We separate the action of invalidating the userdata in Lua and actually dropping the
// userdata type into two phases. This is so that, in the event a userdata drop panics, we
// can be sure that all of the userdata in Lua is actually invalidated.
// All destructors are non-panicking, so this is fine
let to_drop = self
.destructors
.get_mut()
.drain(..)
.flat_map(|(r, dest)| dest(r))
.collect::<Vec<_>>();
drop(to_drop);
}
}
#[allow(clippy::type_complexity)]
enum NonStaticMethod<'lua, T> {
Method(Box<dyn Fn(&'lua Lua, &T, c_int) -> Result<c_int>>),
MethodMut(Box<dyn FnMut(&'lua Lua, &mut T, c_int) -> Result<c_int>>),
Function(Box<dyn Fn(&'lua Lua, c_int) -> Result<c_int>>),
FunctionMut(Box<dyn FnMut(&'lua Lua, c_int) -> Result<c_int>>),
}
struct NonStaticUserDataRegistry<'lua, T> {
// Fields
fields: Vec<(String, NonStaticMethod<'lua, T>)>,
field_getters: Vec<(String, NonStaticMethod<'lua, T>)>,
field_setters: Vec<(String, NonStaticMethod<'lua, T>)>,
meta_fields: Vec<(String, Callback<'lua, 'static>)>,
// Methods
methods: Vec<(String, NonStaticMethod<'lua, T>)>,
meta_methods: Vec<(String, NonStaticMethod<'lua, T>)>,
}
impl<'lua, T> NonStaticUserDataRegistry<'lua, T> {
const fn new() -> NonStaticUserDataRegistry<'lua, T> {
NonStaticUserDataRegistry {
fields: Vec::new(),
field_getters: Vec::new(),
field_setters: Vec::new(),
meta_fields: Vec::new(),
methods: Vec::new(),
meta_methods: Vec::new(),
}
}
}
impl<'lua, T> UserDataFields<'lua, T> for NonStaticUserDataRegistry<'lua, T> {
fn add_field<V>(&mut self, name: impl AsRef<str>, value: V)
where
V: IntoLua<'lua> + Clone + 'static,
{
let name = name.as_ref().to_string();
self.fields.push((
name,
NonStaticMethod::Function(Box::new(move |lua, _| unsafe {
value.clone().push_into_stack_multi(lua)
})),
));
}
fn add_field_method_get<M, R>(&mut self, name: impl AsRef<str>, method: M)
where
M: Fn(&'lua Lua, &T) -> Result<R> + MaybeSend + 'static,
R: IntoLua<'lua>,
{
let method = NonStaticMethod::Method(Box::new(move |lua, ud, _| unsafe {
method(lua, ud)?.push_into_stack_multi(lua)
}));
self.field_getters.push((name.as_ref().into(), method));
}
fn add_field_method_set<M, A>(&mut self, name: impl AsRef<str>, mut method: M)
where
M: FnMut(&'lua Lua, &mut T, A) -> Result<()> + MaybeSend + 'static,
A: FromLua<'lua>,
{
let func_name = format!("{}.{}", short_type_name::<T>(), name.as_ref());
let method = NonStaticMethod::MethodMut(Box::new(move |lua, ud, nargs| unsafe {
let val = A::from_stack_args(nargs, 2, Some(&func_name), lua)?;
method(lua, ud, val)?.push_into_stack_multi(lua)
}));
self.field_setters.push((name.as_ref().into(), method));
}
fn add_field_function_get<F, R>(&mut self, name: impl AsRef<str>, function: F)
where
F: Fn(&'lua Lua, AnyUserData<'lua>) -> Result<R> + MaybeSend + 'static,
R: IntoLua<'lua>,
{
let func_name = format!("{}.{}", short_type_name::<T>(), name.as_ref());
let func = NonStaticMethod::Function(Box::new(move |lua, nargs| unsafe {
let ud = AnyUserData::from_stack_args(nargs, 1, Some(&func_name), lua)?;
function(lua, ud)?.push_into_stack_multi(lua)
}));
self.field_getters.push((name.as_ref().into(), func));
}
fn add_field_function_set<F, A>(&mut self, name: impl AsRef<str>, mut function: F)
where
F: FnMut(&'lua Lua, AnyUserData<'lua>, A) -> Result<()> + MaybeSend + 'static,
A: FromLua<'lua>,
{
let func_name = format!("{}.{}", short_type_name::<T>(), name.as_ref());
let func = NonStaticMethod::FunctionMut(Box::new(move |lua, nargs| unsafe {
let (ud, val) = <_>::from_stack_args(nargs, 1, Some(&func_name), lua)?;
function(lua, ud, val)?.push_into_stack_multi(lua)
}));
self.field_setters.push((name.as_ref().into(), func));
}
fn add_meta_field<V>(&mut self, name: impl AsRef<str>, value: V)
where
V: IntoLua<'lua> + Clone + 'static,
{
let name = name.as_ref().to_string();
let name2 = name.clone();
self.meta_fields.push((
name,
Box::new(move |lua, _| unsafe {
UserDataRegistry::<()>::check_meta_field(lua, &name2, value.clone())?
.push_into_stack_multi(lua)
}),
));
}
fn add_meta_field_with<F, R>(&mut self, name: impl AsRef<str>, f: F)
where
F: Fn(&'lua Lua) -> Result<R> + MaybeSend + 'static,
R: IntoLua<'lua>,
{
let name = name.as_ref().to_string();
let name2 = name.clone();
self.meta_fields.push((
name,
Box::new(move |lua, _| unsafe {
UserDataRegistry::<()>::check_meta_field(lua, &name2, f(lua)?)?
.push_into_stack_multi(lua)
}),
));
}
}
impl<'lua, T> UserDataMethods<'lua, T> for NonStaticUserDataRegistry<'lua, T> {
fn add_method<M, A, R>(&mut self, name: impl AsRef<str>, method: M)
where
M: Fn(&'lua Lua, &T, A) -> Result<R> + MaybeSend + 'static,
A: FromLuaMulti<'lua>,
R: IntoLuaMulti<'lua>,
{
let func_name = format!("{}.{}", short_type_name::<T>(), name.as_ref());
let method = NonStaticMethod::Method(Box::new(move |lua, ud, nargs| unsafe {
let args = A::from_stack_args(nargs, 2, Some(&func_name), lua)?;
method(lua, ud, args)?.push_into_stack_multi(lua)
}));
self.methods.push((name.as_ref().into(), method));
}
fn add_method_mut<M, A, R>(&mut self, name: impl AsRef<str>, mut method: M)
where
M: FnMut(&'lua Lua, &mut T, A) -> Result<R> + MaybeSend + 'static,
A: FromLuaMulti<'lua>,
R: IntoLuaMulti<'lua>,
{
let func_name = format!("{}.{}", short_type_name::<T>(), name.as_ref());
let method = NonStaticMethod::MethodMut(Box::new(move |lua, ud, nargs| unsafe {
let args = A::from_stack_args(nargs, 2, Some(&func_name), lua)?;
method(lua, ud, args)?.push_into_stack_multi(lua)
}));
self.methods.push((name.as_ref().into(), method));
}
#[cfg(feature = "async")]
fn add_async_method<'s, M, A, MR, R>(&mut self, _name: impl AsRef<str>, _method: M)
where
'lua: 's,
T: 'static,
M: Fn(&'lua Lua, &'s T, A) -> MR + MaybeSend + 'static,
A: FromLuaMulti<'lua>,
MR: Future<Output = Result<R>> + 's,
R: IntoLuaMulti<'lua>,
{
// The panic should never happen as async non-static code wouldn't compile
// Non-static lifetime must be bounded to 'lua lifetime
panic!("asynchronous methods are not supported for non-static userdata")
}
#[cfg(feature = "async")]
fn add_async_method_mut<'s, M, A, MR, R>(&mut self, _name: impl AsRef<str>, _method: M)
where
'lua: 's,
T: 'static,
M: Fn(&'lua Lua, &'s mut T, A) -> MR + MaybeSend + 'static,
A: FromLuaMulti<'lua>,
MR: Future<Output = Result<R>> + 's,
R: IntoLuaMulti<'lua>,
{
// The panic should never happen as async non-static code wouldn't compile
// Non-static lifetime must be bounded to 'lua lifetime
panic!("asynchronous methods are not supported for non-static userdata")
}
fn add_function<F, A, R>(&mut self, name: impl AsRef<str>, function: F)
where
F: Fn(&'lua Lua, A) -> Result<R> + MaybeSend + 'static,
A: FromLuaMulti<'lua>,
R: IntoLuaMulti<'lua>,
{
let func_name = format!("{}.{}", short_type_name::<T>(), name.as_ref());
let func = NonStaticMethod::Function(Box::new(move |lua, nargs| unsafe {
let args = A::from_stack_args(nargs, 1, Some(&func_name), lua)?;
function(lua, args)?.push_into_stack_multi(lua)
}));
self.methods.push((name.as_ref().into(), func));
}
fn add_function_mut<F, A, R>(&mut self, name: impl AsRef<str>, mut function: F)
where
F: FnMut(&'lua Lua, A) -> Result<R> + MaybeSend + 'static,
A: FromLuaMulti<'lua>,
R: IntoLuaMulti<'lua>,
{
let func_name = format!("{}.{}", short_type_name::<T>(), name.as_ref());
let func = NonStaticMethod::FunctionMut(Box::new(move |lua, nargs| unsafe {
let args = A::from_stack_args(nargs, 1, Some(&func_name), lua)?;
function(lua, args)?.push_into_stack_multi(lua)
}));
self.methods.push((name.as_ref().into(), func));
}
#[cfg(feature = "async")]
fn add_async_function<F, A, FR, R>(&mut self, _name: impl AsRef<str>, _function: F)
where
F: Fn(&'lua Lua, A) -> FR + MaybeSend + 'static,
A: FromLuaMulti<'lua>,
FR: Future<Output = Result<R>> + 'lua,
R: IntoLuaMulti<'lua>,
{
// The panic should never happen as async non-static code wouldn't compile
// Non-static lifetime must be bounded to 'lua lifetime
panic!("asynchronous functions are not supported for non-static userdata")
}
fn add_meta_method<M, A, R>(&mut self, name: impl AsRef<str>, method: M)
where
M: Fn(&'lua Lua, &T, A) -> Result<R> + MaybeSend + 'static,
A: FromLuaMulti<'lua>,
R: IntoLuaMulti<'lua>,
{
let func_name = format!("{}.{}", short_type_name::<T>(), name.as_ref());
let method = NonStaticMethod::Method(Box::new(move |lua, ud, nargs| unsafe {
let args = A::from_stack_args(nargs, 2, Some(&func_name), lua)?;
method(lua, ud, args)?.push_into_stack_multi(lua)
}));
self.meta_methods.push((name.as_ref().into(), method));
}
fn add_meta_method_mut<M, A, R>(&mut self, name: impl AsRef<str>, mut method: M)
where
M: FnMut(&'lua Lua, &mut T, A) -> Result<R> + MaybeSend + 'static,
A: FromLuaMulti<'lua>,
R: IntoLuaMulti<'lua>,
{
let func_name = format!("{}.{}", short_type_name::<T>(), name.as_ref());
let method = NonStaticMethod::MethodMut(Box::new(move |lua, ud, nargs| unsafe {
let args = A::from_stack_args(nargs, 2, Some(&func_name), lua)?;
method(lua, ud, args)?.push_into_stack_multi(lua)
}));
self.meta_methods.push((name.as_ref().into(), method));
}
#[cfg(all(feature = "async", not(any(feature = "lua51", feature = "luau"))))]
fn add_async_meta_method<'s, M, A, MR, R>(&mut self, _name: impl AsRef<str>, _method: M)
where
'lua: 's,
T: 'static,
M: Fn(&'lua Lua, &'s T, A) -> MR + MaybeSend + 'static,
A: FromLuaMulti<'lua>,
MR: Future<Output = Result<R>> + 's,
R: IntoLuaMulti<'lua>,
{
// The panic should never happen as async non-static code wouldn't compile
// Non-static lifetime must be bounded to 'lua lifetime
panic!("asynchronous meta methods are not supported for non-static userdata")
}
#[cfg(all(feature = "async", not(any(feature = "lua51", feature = "luau"))))]
fn add_async_meta_method_mut<'s, M, A, MR, R>(&mut self, _name: impl AsRef<str>, _method: M)
where
'lua: 's,
T: 'static,
M: Fn(&'lua Lua, &'s mut T, A) -> MR + MaybeSend + 'static,
A: FromLuaMulti<'lua>,
MR: Future<Output = Result<R>> + 's,
R: IntoLuaMulti<'lua>,
{
// The panic should never happen as async non-static code wouldn't compile
// Non-static lifetime must be bounded to 'lua lifetime
panic!("asynchronous meta methods are not supported for non-static userdata")
}
fn add_meta_function<F, A, R>(&mut self, name: impl AsRef<str>, function: F)
where
F: Fn(&'lua Lua, A) -> Result<R> + MaybeSend + 'static,
A: FromLuaMulti<'lua>,
R: IntoLuaMulti<'lua>,
{
let func_name = format!("{}.{}", short_type_name::<T>(), name.as_ref());
let func = NonStaticMethod::Function(Box::new(move |lua, nargs| unsafe {
let args = A::from_stack_args(nargs, 1, Some(&func_name), lua)?;
function(lua, args)?.push_into_stack_multi(lua)
}));
self.meta_methods.push((name.as_ref().into(), func));
}
fn add_meta_function_mut<F, A, R>(&mut self, name: impl AsRef<str>, mut function: F)
where
F: FnMut(&'lua Lua, A) -> Result<R> + MaybeSend + 'static,
A: FromLuaMulti<'lua>,
R: IntoLuaMulti<'lua>,
{
let func_name = format!("{}.{}", short_type_name::<T>(), name.as_ref());
let func = NonStaticMethod::FunctionMut(Box::new(move |lua, nargs| unsafe {
let args = A::from_stack_args(nargs, 1, Some(&func_name), lua)?;
function(lua, args)?.push_into_stack_multi(lua)
}));
self.meta_methods.push((name.as_ref().into(), func));
}
#[cfg(all(feature = "async", not(any(feature = "lua51", feature = "luau"))))]
fn add_async_meta_function<F, A, FR, R>(&mut self, _name: impl AsRef<str>, _function: F)
where
F: Fn(&'lua Lua, A) -> FR + MaybeSend + 'static,
A: FromLuaMulti<'lua>,
FR: Future<Output = Result<R>> + 'lua,
R: IntoLuaMulti<'lua>,
{
// The panic should never happen as async non-static code wouldn't compile
// Non-static lifetime must be bounded to 'lua lifetime
panic!("asynchronous meta functions are not supported for non-static userdata")
}
}