rhai/src/func/native.rs
2023-02-10 23:42:13 +08:00

630 lines
20 KiB
Rust

//! Module defining interfaces to native-Rust functions.
use super::call::FnCallArgs;
use crate::ast::FnCallHashes;
use crate::eval::{Caches, GlobalRuntimeState};
use crate::plugin::PluginFunction;
use crate::tokenizer::{is_valid_function_name, Token, TokenizeState};
use crate::types::dynamic::Variant;
use crate::{
calc_fn_hash, Dynamic, Engine, EvalContext, FuncArgs, Position, RhaiResult, RhaiResultOf,
StaticVec, VarDefInfo, ERR,
};
use std::any::{type_name, TypeId};
#[cfg(feature = "no_std")]
use std::prelude::v1::*;
/// Trait that maps to `Send + Sync` only under the `sync` feature.
#[cfg(feature = "sync")]
pub trait SendSync: Send + Sync {}
/// Trait that maps to `Send + Sync` only under the `sync` feature.
#[cfg(feature = "sync")]
impl<T: Send + Sync> SendSync for T {}
/// Trait that maps to `Send + Sync` only under the `sync` feature.
#[cfg(not(feature = "sync"))]
pub trait SendSync {}
/// Trait that maps to `Send + Sync` only under the `sync` feature.
#[cfg(not(feature = "sync"))]
impl<T> SendSync for T {}
/// Immutable reference-counted container.
#[cfg(not(feature = "sync"))]
pub use std::rc::Rc as Shared;
/// Immutable reference-counted container.
#[cfg(feature = "sync")]
pub use std::sync::Arc as Shared;
/// Synchronized shared object.
#[cfg(not(feature = "sync"))]
pub use std::cell::RefCell as Locked;
/// Read-only lock guard for synchronized shared object.
#[cfg(not(feature = "sync"))]
pub type LockGuard<'a, T> = std::cell::Ref<'a, T>;
/// Mutable lock guard for synchronized shared object.
#[cfg(not(feature = "sync"))]
pub type LockGuardMut<'a, T> = std::cell::RefMut<'a, T>;
/// Synchronized shared object.
#[cfg(feature = "sync")]
#[allow(dead_code)]
pub use std::sync::RwLock as Locked;
/// Read-only lock guard for synchronized shared object.
#[cfg(feature = "sync")]
#[allow(dead_code)]
pub type LockGuard<'a, T> = std::sync::RwLockReadGuard<'a, T>;
/// Mutable lock guard for synchronized shared object.
#[cfg(feature = "sync")]
#[allow(dead_code)]
pub type LockGuardMut<'a, T> = std::sync::RwLockWriteGuard<'a, T>;
/// Context of a native Rust function call.
#[derive(Debug)]
pub struct NativeCallContext<'a> {
/// The current [`Engine`].
engine: &'a Engine,
/// Name of function called.
fn_name: &'a str,
/// Function source, if any.
source: Option<&'a str>,
/// The current [`GlobalRuntimeState`], if any.
global: &'a GlobalRuntimeState,
/// [Position] of the function call.
pos: Position,
}
/// _(internals)_ Context of a native Rust function call.
/// Exported under the `internals` feature only.
///
/// # WARNING - Volatile Type
///
/// This type is volatile and may change in the future.
#[deprecated = "This type is NOT deprecated, but it is considered volatile and may change in the future."]
#[cfg(feature = "internals")]
#[derive(Debug, Clone)]
pub struct NativeCallContextStore {
/// Name of function called.
pub fn_name: String,
/// Function source, if any.
pub source: Option<String>,
/// The current [`GlobalRuntimeState`], if any.
pub global: GlobalRuntimeState,
/// [Position] of the function call.
pub pos: Position,
}
#[cfg(feature = "internals")]
#[allow(deprecated)]
impl NativeCallContextStore {
/// Create a [`NativeCallContext`] from a [`NativeCallContextStore`].
///
/// # WARNING - Unstable API
///
/// This API is volatile and may change in the future.
#[deprecated = "This API is NOT deprecated, but it is considered volatile and may change in the future."]
#[inline(always)]
#[must_use]
pub fn create_context<'a>(&'a self, engine: &'a Engine) -> NativeCallContext<'a> {
NativeCallContext::from_stored_data(engine, self)
}
}
impl<'a>
From<(
&'a Engine,
&'a str,
Option<&'a str>,
&'a GlobalRuntimeState,
Position,
)> for NativeCallContext<'a>
{
#[inline(always)]
fn from(
value: (
&'a Engine,
&'a str,
Option<&'a str>,
&'a GlobalRuntimeState,
Position,
),
) -> Self {
Self {
engine: value.0,
fn_name: value.1,
source: value.2,
global: value.3,
pos: value.4,
}
}
}
impl<'a> NativeCallContext<'a> {
/// _(internals)_ Create a new [`NativeCallContext`].
/// Exported under the `internals` feature only.
///
/// Not available under `no_module`.
#[cfg(feature = "internals")]
#[cfg(not(feature = "no_module"))]
#[inline(always)]
#[must_use]
pub const fn new_with_all_fields(
engine: &'a Engine,
fn_name: &'a str,
source: Option<&'a str>,
global: &'a GlobalRuntimeState,
pos: Position,
) -> Self {
Self {
engine,
fn_name,
source,
global,
pos,
}
}
/// _(internals)_ Create a [`NativeCallContext`] from a [`NativeCallContextStore`].
/// Exported under the `internals` feature only.
///
/// # WARNING - Unstable API
///
/// This API is volatile and may change in the future.
#[deprecated = "This API is NOT deprecated, but it is considered volatile and may change in the future."]
#[cfg(feature = "internals")]
#[inline]
#[must_use]
#[allow(deprecated)]
pub fn from_stored_data(engine: &'a Engine, context: &'a NativeCallContextStore) -> Self {
Self {
engine,
fn_name: &context.fn_name,
source: context.source.as_deref(),
global: &context.global,
pos: context.pos,
}
}
/// _(internals)_ Store this [`NativeCallContext`] into a [`NativeCallContextStore`].
/// Exported under the `internals` feature only.
///
/// # WARNING - Unstable API
///
/// This API is volatile and may change in the future.
#[deprecated = "This API is NOT deprecated, but it is considered volatile and may change in the future."]
#[cfg(feature = "internals")]
#[inline]
#[must_use]
#[allow(deprecated)]
pub fn store_data(&self) -> NativeCallContextStore {
NativeCallContextStore {
fn_name: self.fn_name.to_string(),
source: self.source.map(ToString::to_string),
global: self.global.clone(),
pos: self.pos,
}
}
/// The current [`Engine`].
#[inline(always)]
#[must_use]
pub const fn engine(&self) -> &Engine {
self.engine
}
/// Name of the function called.
#[inline(always)]
#[must_use]
pub const fn fn_name(&self) -> &str {
self.fn_name
}
/// [Position] of the function call.
#[inline(always)]
#[must_use]
pub const fn position(&self) -> Position {
self.pos
}
/// Current nesting level of function calls.
#[inline(always)]
#[must_use]
pub const fn call_level(&self) -> usize {
self.global.level
}
/// The current source.
#[inline(always)]
#[must_use]
pub const fn source(&self) -> Option<&str> {
self.source
}
/// Custom state kept in a [`Dynamic`].
#[inline(always)]
#[must_use]
pub const fn tag(&self) -> Option<&Dynamic> {
Some(&self.global.tag)
}
/// Get an iterator over the current set of modules imported via `import` statements
/// in reverse order.
///
/// Not available under `no_module`.
#[cfg(not(feature = "no_module"))]
#[inline]
pub fn iter_imports(&self) -> impl Iterator<Item = (&str, &crate::Module)> {
self.global.iter_imports()
}
/// Get an iterator over the current set of modules imported via `import` statements in reverse order.
#[cfg(not(feature = "no_module"))]
#[allow(dead_code)]
#[inline]
pub(crate) fn iter_imports_raw(
&self,
) -> impl Iterator<Item = (&crate::ImmutableString, &crate::SharedModule)> {
self.global.iter_imports_raw()
}
/// _(internals)_ The current [`GlobalRuntimeState`], if any.
/// Exported under the `internals` feature only.
///
/// Not available under `no_module`.
#[cfg(feature = "internals")]
#[inline(always)]
#[must_use]
pub const fn global_runtime_state(&self) -> &GlobalRuntimeState {
self.global
}
/// _(internals)_ The current [`GlobalRuntimeState`], if any.
#[cfg(not(feature = "internals"))]
#[inline(always)]
#[must_use]
#[allow(dead_code)]
pub(crate) const fn global_runtime_state(&self) -> &GlobalRuntimeState {
self.global
}
/// Get an iterator over the namespaces containing definitions of all script-defined functions
/// in reverse order (i.e. parent namespaces are iterated after child namespaces).
///
/// Not available under `no_function`.
#[cfg(not(feature = "no_function"))]
#[inline]
pub fn iter_namespaces(&self) -> impl Iterator<Item = &crate::Module> {
self.global.lib.iter().map(AsRef::as_ref)
}
/// _(internals)_ The current stack of namespaces containing definitions of all script-defined functions.
/// Exported under the `internals` feature only.
///
/// Not available under `no_function`.
#[cfg(not(feature = "no_function"))]
#[cfg(feature = "internals")]
#[inline(always)]
#[must_use]
pub fn namespaces(&self) -> &[crate::SharedModule] {
&self.global.lib
}
/// Call a function inside the call context with the provided arguments.
#[inline]
pub fn call_fn<T: Variant + Clone>(
&self,
fn_name: impl AsRef<str>,
args: impl FuncArgs,
) -> RhaiResultOf<T> {
let mut arg_values = StaticVec::new_const();
args.parse(&mut arg_values);
let mut args: StaticVec<_> = arg_values.iter_mut().collect();
self._call_fn_raw(fn_name, &mut args, false, false, false)
.and_then(|result| {
// Bail out early if the return type needs no cast
if TypeId::of::<T>() == TypeId::of::<Dynamic>() {
return Ok(reify! { result => T });
}
let typ = self.engine().map_type_name(result.type_name());
result.try_cast().ok_or_else(|| {
let t = self.engine().map_type_name(type_name::<T>()).into();
ERR::ErrorMismatchOutputType(t, typ.into(), Position::NONE).into()
})
})
}
/// Call a registered native Rust function inside the call context with the provided arguments.
///
/// This is often useful because Rust functions typically only want to cross-call other
/// registered Rust functions and not have to worry about scripted functions hijacking the
/// process unknowingly (or deliberately).
#[inline]
pub fn call_native_fn<T: Variant + Clone>(
&self,
fn_name: impl AsRef<str>,
args: impl FuncArgs,
) -> RhaiResultOf<T> {
let mut arg_values = StaticVec::new_const();
args.parse(&mut arg_values);
let mut args: StaticVec<_> = arg_values.iter_mut().collect();
self._call_fn_raw(fn_name, &mut args, true, false, false)
.and_then(|result| {
// Bail out early if the return type needs no cast
if TypeId::of::<T>() == TypeId::of::<Dynamic>() {
return Ok(reify! { result => T });
}
let typ = self.engine().map_type_name(result.type_name());
result.try_cast().ok_or_else(|| {
let t = self.engine().map_type_name(type_name::<T>()).into();
ERR::ErrorMismatchOutputType(t, typ.into(), Position::NONE).into()
})
})
}
/// Call a function (native Rust or scripted) inside the call context.
///
/// If `is_method_call` is [`true`], the first argument is assumed to be the `this` pointer for
/// a script-defined function (or the object of a method call).
///
/// # WARNING - Low Level API
///
/// This function is very low level.
///
/// # Arguments
///
/// All arguments may be _consumed_, meaning that they may be replaced by `()`. This is to avoid
/// unnecessarily cloning the arguments.
///
/// **DO NOT** reuse the arguments after this call. If they are needed afterwards, clone them
/// _before_ calling this function.
///
/// If `is_ref_mut` is [`true`], the first argument is assumed to be passed by reference and is
/// not consumed.
#[inline(always)]
pub fn call_fn_raw(
&self,
fn_name: impl AsRef<str>,
is_ref_mut: bool,
is_method_call: bool,
args: &mut [&mut Dynamic],
) -> RhaiResult {
let name = fn_name.as_ref();
let native_only = !is_valid_function_name(name);
#[cfg(not(feature = "no_function"))]
let native_only = native_only && !crate::parser::is_anonymous_fn(name);
self._call_fn_raw(fn_name, args, native_only, is_ref_mut, is_method_call)
}
/// Call a registered native Rust function inside the call context.
///
/// This is often useful because Rust functions typically only want to cross-call other
/// registered Rust functions and not have to worry about scripted functions hijacking the
/// process unknowingly (or deliberately).
///
/// # WARNING - Low Level API
///
/// This function is very low level.
///
/// # Arguments
///
/// All arguments may be _consumed_, meaning that they may be replaced by `()`. This is to avoid
/// unnecessarily cloning the arguments.
///
/// **DO NOT** reuse the arguments after this call. If they are needed afterwards, clone them
/// _before_ calling this function.
///
/// If `is_ref_mut` is [`true`], the first argument is assumed to be passed by reference and is
/// not consumed.
#[inline(always)]
pub fn call_native_fn_raw(
&self,
fn_name: impl AsRef<str>,
is_ref_mut: bool,
args: &mut [&mut Dynamic],
) -> RhaiResult {
self._call_fn_raw(fn_name, args, true, is_ref_mut, false)
}
/// Call a function (native Rust or scripted) inside the call context.
fn _call_fn_raw(
&self,
fn_name: impl AsRef<str>,
args: &mut [&mut Dynamic],
native_only: bool,
is_ref_mut: bool,
is_method_call: bool,
) -> RhaiResult {
let global = &mut self.global.clone();
global.level += 1;
let caches = &mut Caches::new();
let fn_name = fn_name.as_ref();
let op_token = Token::lookup_symbol_from_syntax(fn_name);
let args_len = args.len();
if native_only {
return self
.engine()
.exec_native_fn_call(
global,
caches,
fn_name,
op_token.as_ref(),
calc_fn_hash(None, fn_name, args_len),
args,
is_ref_mut,
Position::NONE,
)
.map(|(r, ..)| r);
}
// Native or script
let hash = if is_method_call {
FnCallHashes::from_all(
#[cfg(not(feature = "no_function"))]
calc_fn_hash(None, fn_name, args_len - 1),
calc_fn_hash(None, fn_name, args_len),
)
} else {
calc_fn_hash(None, fn_name, args_len).into()
};
self.engine()
.exec_fn_call(
global,
caches,
None,
fn_name,
op_token.as_ref(),
hash,
args,
is_ref_mut,
is_method_call,
Position::NONE,
)
.map(|(r, ..)| r)
}
}
/// Return a mutable reference to the wrapped value of a [`Shared`] resource.
/// If the resource is shared (i.e. has other outstanding references), a cloned copy is used.
#[inline(always)]
#[must_use]
#[allow(dead_code)]
pub fn shared_make_mut<T: Clone>(value: &mut Shared<T>) -> &mut T {
Shared::make_mut(value)
}
/// Return a mutable reference to the wrapped value of a [`Shared`] resource.
#[inline(always)]
#[must_use]
#[allow(dead_code)]
pub fn shared_get_mut<T: Clone>(value: &mut Shared<T>) -> Option<&mut T> {
Shared::get_mut(value)
}
/// Consume a [`Shared`] resource if is unique (i.e. not shared), or clone it otherwise.
#[inline]
#[must_use]
#[allow(dead_code)]
pub fn shared_take_or_clone<T: Clone>(value: Shared<T>) -> T {
shared_try_take(value).unwrap_or_else(|v| v.as_ref().clone())
}
/// Consume a [`Shared`] resource if is unique (i.e. not shared).
#[inline(always)]
#[allow(dead_code)]
pub fn shared_try_take<T>(value: Shared<T>) -> Result<T, Shared<T>> {
Shared::try_unwrap(value)
}
/// Consume a [`Shared`] resource, assuming that it is unique (i.e. not shared).
///
/// # Panics
///
/// Panics if the resource is shared (i.e. has other outstanding references).
#[inline]
#[must_use]
#[allow(dead_code)]
pub fn shared_take<T>(value: Shared<T>) -> T {
shared_try_take(value).ok().expect("not shared")
}
/// _(internals)_ Lock a [`Locked`] resource for mutable access.
/// Exported under the `internals` feature only.
#[inline(always)]
#[must_use]
#[allow(dead_code)]
pub fn locked_read<T>(value: &Locked<T>) -> LockGuard<T> {
#[cfg(not(feature = "sync"))]
return value.borrow();
#[cfg(feature = "sync")]
return value.read().unwrap();
}
/// _(internals)_ Lock a [`Locked`] resource for mutable access.
/// Exported under the `internals` feature only.
#[inline(always)]
#[must_use]
#[allow(dead_code)]
pub fn locked_write<T>(value: &Locked<T>) -> LockGuardMut<T> {
#[cfg(not(feature = "sync"))]
return value.borrow_mut();
#[cfg(feature = "sync")]
return value.write().unwrap();
}
/// General Rust function trail object.
#[cfg(not(feature = "sync"))]
pub type FnAny = dyn Fn(Option<NativeCallContext>, &mut FnCallArgs) -> RhaiResult;
/// General Rust function trail object.
#[cfg(feature = "sync")]
pub type FnAny = dyn Fn(Option<NativeCallContext>, &mut FnCallArgs) -> RhaiResult + Send + Sync;
/// Built-in function trait object.
pub type FnBuiltin = (
fn(Option<NativeCallContext>, &mut FnCallArgs) -> RhaiResult,
bool,
);
/// Function that gets an iterator from a type.
#[cfg(not(feature = "sync"))]
pub type IteratorFn = dyn Fn(Dynamic) -> Box<dyn Iterator<Item = RhaiResultOf<Dynamic>>>;
/// Function that gets an iterator from a type.
#[cfg(feature = "sync")]
pub type IteratorFn =
dyn Fn(Dynamic) -> Box<dyn Iterator<Item = RhaiResultOf<Dynamic>>> + Send + Sync;
/// Plugin function trait object.
#[cfg(not(feature = "sync"))]
pub type FnPlugin = dyn PluginFunction;
/// Plugin function trait object.
#[cfg(feature = "sync")]
pub type FnPlugin = dyn PluginFunction + Send + Sync;
/// Callback function for progress reporting.
#[cfg(not(feature = "unchecked"))]
#[cfg(not(feature = "sync"))]
pub type OnProgressCallback = dyn Fn(u64) -> Option<Dynamic>;
/// Callback function for progress reporting.
#[cfg(not(feature = "unchecked"))]
#[cfg(feature = "sync")]
pub type OnProgressCallback = dyn Fn(u64) -> Option<Dynamic> + Send + Sync;
/// Callback function for printing.
#[cfg(not(feature = "sync"))]
pub type OnPrintCallback = dyn Fn(&str);
/// Callback function for printing.
#[cfg(feature = "sync")]
pub type OnPrintCallback = dyn Fn(&str) + Send + Sync;
/// Callback function for debugging.
#[cfg(not(feature = "sync"))]
pub type OnDebugCallback = dyn Fn(&str, Option<&str>, Position);
/// Callback function for debugging.
#[cfg(feature = "sync")]
pub type OnDebugCallback = dyn Fn(&str, Option<&str>, Position) + Send + Sync;
/// Callback function for mapping tokens during parsing.
#[cfg(not(feature = "sync"))]
pub type OnParseTokenCallback = dyn Fn(Token, Position, &TokenizeState) -> Token;
/// Callback function for mapping tokens during parsing.
#[cfg(feature = "sync")]
pub type OnParseTokenCallback = dyn Fn(Token, Position, &TokenizeState) -> Token + Send + Sync;
/// Callback function for variable access.
#[cfg(not(feature = "sync"))]
pub type OnVarCallback = dyn Fn(&str, usize, EvalContext) -> RhaiResultOf<Option<Dynamic>>;
/// Callback function for variable access.
#[cfg(feature = "sync")]
pub type OnVarCallback =
dyn Fn(&str, usize, EvalContext) -> RhaiResultOf<Option<Dynamic>> + Send + Sync;
/// Callback function for variable definition.
#[cfg(not(feature = "sync"))]
pub type OnDefVarCallback = dyn Fn(bool, VarDefInfo, EvalContext) -> RhaiResultOf<bool>;
/// Callback function for variable definition.
#[cfg(feature = "sync")]
pub type OnDefVarCallback =
dyn Fn(bool, VarDefInfo, EvalContext) -> RhaiResultOf<bool> + Send + Sync;