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use anyhow::{bail, Result};
use std::fmt::{self, Display};
use wasmtime_environ::{
EngineOrModuleTypeIndex, EntityType, Global, Memory, ModuleTypes, Table, TypeTrace,
VMSharedTypeIndex, WasmArrayType, WasmCompositeType, WasmFieldType, WasmFuncType, WasmHeapType,
WasmRefType, WasmStorageType, WasmSubType, WasmValType,
};
use crate::{type_registry::RegisteredType, Engine};
pub(crate) mod matching;
// Type Representations
// Type attributes
/// Indicator of whether a global is mutable or not
#[derive(Debug, Clone, Copy, Hash, Eq, PartialEq)]
pub enum Mutability {
/// The global is constant and its value does not change
Const,
/// The value of the global can change over time
Var,
}
// Value Types
/// A list of all possible value types in WebAssembly.
///
/// # Subtyping and Equality
///
/// `ValType` does not implement `Eq`, because reference types have a subtyping
/// relationship, and so 99.99% of the time you actually want to check whether
/// one type matches (i.e. is a subtype of) another type. You can use the
/// [`ValType::matches`] and [`Val::matches_ty`][crate::Val::matches_ty] methods
/// to perform these types of checks. If, however, you are in that 0.01%
/// scenario where you need to check precise equality between types, you can use
/// the [`ValType::eq`] method.
#[derive(Clone, Hash)]
pub enum ValType {
// NB: the ordering of variants here is intended to match the ordering in
// `wasmtime_types::WasmType` to help improve codegen when converting.
//
/// Signed 32 bit integer.
I32,
/// Signed 64 bit integer.
I64,
/// Floating point 32 bit integer.
F32,
/// Floating point 64 bit integer.
F64,
/// A 128 bit number.
V128,
/// An opaque reference to some type on the heap.
Ref(RefType),
}
impl fmt::Debug for ValType {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
fmt::Display::fmt(self, f)
}
}
impl Display for ValType {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
match self {
ValType::I32 => write!(f, "i32"),
ValType::I64 => write!(f, "i64"),
ValType::F32 => write!(f, "f32"),
ValType::F64 => write!(f, "f64"),
ValType::V128 => write!(f, "v128"),
ValType::Ref(r) => Display::fmt(r, f),
}
}
}
impl From<RefType> for ValType {
#[inline]
fn from(r: RefType) -> Self {
ValType::Ref(r)
}
}
impl ValType {
/// The `externref` type, aka `(ref null extern)`.
pub const EXTERNREF: Self = ValType::Ref(RefType::EXTERNREF);
/// The `funcref` type, aka `(ref null func)`.
pub const FUNCREF: Self = ValType::Ref(RefType::FUNCREF);
/// The `nullfuncref` type, aka `(ref null nofunc)`.
pub const NULLFUNCREF: Self = ValType::Ref(RefType::NULLFUNCREF);
/// The `anyref` type, aka `(ref null any)`.
pub const ANYREF: Self = ValType::Ref(RefType::ANYREF);
/// The `i31ref` type, aka `(ref null i31)`.
pub const I31REF: Self = ValType::Ref(RefType::I31REF);
/// The `nullref` type, aka `(ref null none)`.
pub const NULLREF: Self = ValType::Ref(RefType::NULLREF);
/// Returns true if `ValType` matches any of the numeric types. (e.g. `I32`,
/// `I64`, `F32`, `F64`).
#[inline]
pub fn is_num(&self) -> bool {
match self {
ValType::I32 | ValType::I64 | ValType::F32 | ValType::F64 => true,
_ => false,
}
}
/// Is this the `i32` type?
#[inline]
pub fn is_i32(&self) -> bool {
matches!(self, ValType::I32)
}
/// Is this the `i64` type?
#[inline]
pub fn is_i64(&self) -> bool {
matches!(self, ValType::I64)
}
/// Is this the `f32` type?
#[inline]
pub fn is_f32(&self) -> bool {
matches!(self, ValType::F32)
}
/// Is this the `f64` type?
#[inline]
pub fn is_f64(&self) -> bool {
matches!(self, ValType::F64)
}
/// Is this the `v128` type?
#[inline]
pub fn is_v128(&self) -> bool {
matches!(self, ValType::V128)
}
/// Returns true if `ValType` is any kind of reference type.
#[inline]
pub fn is_ref(&self) -> bool {
matches!(self, ValType::Ref(_))
}
/// Is this the `funcref` (aka `(ref null func)`) type?
#[inline]
pub fn is_funcref(&self) -> bool {
matches!(
self,
ValType::Ref(RefType {
is_nullable: true,
heap_type: HeapType::Func
})
)
}
/// Is this the `externref` (aka `(ref null extern)`) type?
#[inline]
pub fn is_externref(&self) -> bool {
matches!(
self,
ValType::Ref(RefType {
is_nullable: true,
heap_type: HeapType::Extern
})
)
}
/// Is this the `anyref` (aka `(ref null any)`) type?
#[inline]
pub fn is_anyref(&self) -> bool {
matches!(
self,
ValType::Ref(RefType {
is_nullable: true,
heap_type: HeapType::Any
})
)
}
/// Get the underlying reference type, if this value type is a reference
/// type.
#[inline]
pub fn as_ref(&self) -> Option<&RefType> {
match self {
ValType::Ref(r) => Some(r),
_ => None,
}
}
/// Get the underlying reference type, panicking if this value type is not a
/// reference type.
#[inline]
pub fn unwrap_ref(&self) -> &RefType {
self.as_ref()
.expect("ValType::unwrap_ref on a non-reference type")
}
/// Does this value type match the other type?
///
/// That is, is this value type a subtype of the other?
///
/// # Panics
///
/// Panics if either type is associated with a different engine from the
/// other.
pub fn matches(&self, other: &ValType) -> bool {
match (self, other) {
(Self::I32, Self::I32) => true,
(Self::I64, Self::I64) => true,
(Self::F32, Self::F32) => true,
(Self::F64, Self::F64) => true,
(Self::V128, Self::V128) => true,
(Self::Ref(a), Self::Ref(b)) => a.matches(b),
(Self::I32, _)
| (Self::I64, _)
| (Self::F32, _)
| (Self::F64, _)
| (Self::V128, _)
| (Self::Ref(_), _) => false,
}
}
/// Is value type `a` precisely equal to value type `b`?
///
/// Returns `false` even if `a` is a subtype of `b` or vice versa, if they
/// are not exactly the same value type.
///
/// # Panics
///
/// Panics if either type is associated with a different engine.
pub fn eq(a: &Self, b: &Self) -> bool {
a.matches(b) && b.matches(a)
}
pub(crate) fn ensure_matches(&self, engine: &Engine, other: &ValType) -> Result<()> {
if !self.comes_from_same_engine(engine) || !other.comes_from_same_engine(engine) {
bail!("type used with wrong engine");
}
if self.matches(other) {
Ok(())
} else {
bail!("type mismatch: expected {other}, found {self}")
}
}
pub(crate) fn comes_from_same_engine(&self, engine: &Engine) -> bool {
match self {
Self::I32 | Self::I64 | Self::F32 | Self::F64 | Self::V128 => true,
Self::Ref(r) => r.comes_from_same_engine(engine),
}
}
pub(crate) fn to_wasm_type(&self) -> WasmValType {
match self {
Self::I32 => WasmValType::I32,
Self::I64 => WasmValType::I64,
Self::F32 => WasmValType::F32,
Self::F64 => WasmValType::F64,
Self::V128 => WasmValType::V128,
Self::Ref(r) => WasmValType::Ref(r.to_wasm_type()),
}
}
#[inline]
pub(crate) fn from_wasm_type(engine: &Engine, ty: &WasmValType) -> Self {
match ty {
WasmValType::I32 => Self::I32,
WasmValType::I64 => Self::I64,
WasmValType::F32 => Self::F32,
WasmValType::F64 => Self::F64,
WasmValType::V128 => Self::V128,
WasmValType::Ref(r) => Self::Ref(RefType::from_wasm_type(engine, r)),
}
}
}
/// Opaque references to data in the Wasm heap or to host data.
///
/// # Subtyping and Equality
///
/// `RefType` does not implement `Eq`, because reference types have a subtyping
/// relationship, and so 99.99% of the time you actually want to check whether
/// one type matches (i.e. is a subtype of) another type. You can use the
/// [`RefType::matches`] and [`Ref::matches_ty`][crate::Ref::matches_ty] methods
/// to perform these types of checks. If, however, you are in that 0.01%
/// scenario where you need to check precise equality between types, you can use
/// the [`RefType::eq`] method.
#[derive(Clone, Hash)]
pub struct RefType {
is_nullable: bool,
heap_type: HeapType,
}
impl fmt::Debug for RefType {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
Display::fmt(self, f)
}
}
impl fmt::Display for RefType {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "(ref ")?;
if self.is_nullable() {
write!(f, "null ")?;
}
write!(f, "{})", self.heap_type())
}
}
impl RefType {
/// The `externref` type, aka `(ref null extern)`.
pub const EXTERNREF: Self = RefType {
is_nullable: true,
heap_type: HeapType::Extern,
};
/// The `funcref` type, aka `(ref null func)`.
pub const FUNCREF: Self = RefType {
is_nullable: true,
heap_type: HeapType::Func,
};
/// The `nullfuncref` type, aka `(ref null nofunc)`.
pub const NULLFUNCREF: Self = RefType {
is_nullable: true,
heap_type: HeapType::NoFunc,
};
/// The `anyref` type, aka `(ref null any)`.
pub const ANYREF: Self = RefType {
is_nullable: true,
heap_type: HeapType::Any,
};
/// The `i31ref` type, aka `(ref null i31)`.
pub const I31REF: Self = RefType {
is_nullable: true,
heap_type: HeapType::I31,
};
/// The `nullref` type, aka `(ref null none)`.
pub const NULLREF: Self = RefType {
is_nullable: true,
heap_type: HeapType::None,
};
/// Construct a new reference type.
pub fn new(is_nullable: bool, heap_type: HeapType) -> RefType {
RefType {
is_nullable,
heap_type,
}
}
/// Can this type of reference be null?
pub fn is_nullable(&self) -> bool {
self.is_nullable
}
/// The heap type that this is a reference to.
#[inline]
pub fn heap_type(&self) -> &HeapType {
&self.heap_type
}
/// Does this reference type match the other?
///
/// That is, is this reference type a subtype of the other?
///
/// # Panics
///
/// Panics if either type is associated with a different engine from the
/// other.
pub fn matches(&self, other: &RefType) -> bool {
if self.is_nullable() && !other.is_nullable() {
return false;
}
self.heap_type().matches(other.heap_type())
}
/// Is reference type `a` precisely equal to reference type `b`?
///
/// Returns `false` even if `a` is a subtype of `b` or vice versa, if they
/// are not exactly the same reference type.
///
/// # Panics
///
/// Panics if either type is associated with a different engine.
pub fn eq(a: &RefType, b: &RefType) -> bool {
a.matches(b) && b.matches(a)
}
pub(crate) fn ensure_matches(&self, engine: &Engine, other: &RefType) -> Result<()> {
if !self.comes_from_same_engine(engine) || !other.comes_from_same_engine(engine) {
bail!("type used with wrong engine");
}
if self.matches(other) {
Ok(())
} else {
bail!("type mismatch: expected {other}, found {self}")
}
}
pub(crate) fn comes_from_same_engine(&self, engine: &Engine) -> bool {
self.heap_type().comes_from_same_engine(engine)
}
pub(crate) fn to_wasm_type(&self) -> WasmRefType {
WasmRefType {
nullable: self.is_nullable(),
heap_type: self.heap_type().to_wasm_type(),
}
}
pub(crate) fn from_wasm_type(engine: &Engine, ty: &WasmRefType) -> RefType {
RefType {
is_nullable: ty.nullable,
heap_type: HeapType::from_wasm_type(engine, &ty.heap_type),
}
}
pub(crate) fn is_gc_heap_type(&self) -> bool {
self.heap_type().is_vmgcref_type_and_points_to_object()
}
}
/// The heap types that can Wasm can have references to.
///
/// # Subtyping and Equality
///
/// `HeapType` does not implement `Eq`, because heap types have a subtyping
/// relationship, and so 99.99% of the time you actually want to check whether
/// one type matches (i.e. is a subtype of) another type. You can use the
/// [`HeapType::matches`] method to perform these types of checks. If, however,
/// you are in that 0.01% scenario where you need to check precise equality
/// between types, you can use the [`HeapType::eq`] method.
#[derive(Debug, Clone, Hash)]
pub enum HeapType {
/// The abstract `extern` heap type represents external host data.
Extern,
/// The abstract `func` heap type represents a reference to any kind of
/// function.
///
/// This is the top type for the function references type hierarchy, and is
/// therefore a supertype of every function reference.
Func,
/// A reference to a function of a specific, concrete type.
///
/// These are subtypes of `func` and supertypes of `nofunc`.
ConcreteFunc(FuncType),
/// The abstract `nofunc` heap type represents the null function reference.
///
/// This is the bottom type for the function references type hierarchy, and
/// therefore `nofunc` is a subtype of all function reference types.
NoFunc,
/// The abstract `any` heap type represents all internal Wasm data.
///
/// This is the top type of the internal type hierarchy, and is therefore a
/// supertype of all internal types (such as `i31`, `struct`s, and
/// `array`s).
Any,
/// The `i31` heap type represents unboxed 31-bit integers.
///
/// This is a subtype of `any` and a supertype of `none`.
I31,
/// The abstract `array` heap type represents a reference to any kind of array.
///
/// This is a subtype of `any` and a supertype of all concrete array types,
/// as well as a supertype of the abstract `none` heap type.
//
// TODO: add docs for subtype of `eq` once we add that heap type
Array,
/// A reference to an array of a specific, concrete type.
///
/// These are subtypes of the `array` heap type (therefore also a subtype of
/// `any`) and supertypes of the `none` heap type.
//
// TODO: add docs for subtype of `eq` once we add that heap type
ConcreteArray(ArrayType),
/// The abstract `none` heap type represents the null internal reference.
///
/// This is the bottom type for the internal type hierarchy, and therefore
/// `none` is a subtype of internal types.
None,
}
impl Display for HeapType {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match self {
HeapType::Extern => write!(f, "extern"),
HeapType::Func => write!(f, "func"),
HeapType::NoFunc => write!(f, "nofunc"),
HeapType::Any => write!(f, "any"),
HeapType::I31 => write!(f, "i31"),
HeapType::Array => write!(f, "array"),
HeapType::None => write!(f, "none"),
HeapType::ConcreteFunc(ty) => write!(f, "(concrete func {:?})", ty.type_index()),
HeapType::ConcreteArray(ty) => write!(f, "(concrete array {:?})", ty.type_index()),
}
}
}
impl From<FuncType> for HeapType {
#[inline]
fn from(f: FuncType) -> Self {
HeapType::ConcreteFunc(f)
}
}
impl From<ArrayType> for HeapType {
#[inline]
fn from(a: ArrayType) -> Self {
HeapType::ConcreteArray(a)
}
}
impl HeapType {
/// Is this the abstract `extern` heap type?
pub fn is_extern(&self) -> bool {
matches!(self, HeapType::Extern)
}
/// Is this the abstract `func` heap type?
pub fn is_func(&self) -> bool {
matches!(self, HeapType::Func)
}
/// Is this the abstract `nofunc` heap type?
pub fn is_no_func(&self) -> bool {
matches!(self, HeapType::NoFunc)
}
/// Is this the abstract `any` heap type?
pub fn is_any(&self) -> bool {
matches!(self, HeapType::Any)
}
/// Is this the abstract `i31` heap type?
pub fn is_i31(&self) -> bool {
matches!(self, HeapType::I31)
}
/// Is this the abstract `none` heap type?
pub fn is_none(&self) -> bool {
matches!(self, HeapType::None)
}
/// Is this an abstract type?
///
/// Types that are not abstract are concrete, user-defined types.
pub fn is_abstract(&self) -> bool {
!self.is_concrete()
}
/// Is this a concrete, user-defined heap type?
///
/// Types that are not concrete, user-defined types are abstract types.
#[inline]
pub fn is_concrete(&self) -> bool {
matches!(self, HeapType::ConcreteFunc(_) | HeapType::ConcreteArray(_))
}
/// Is this a concrete, user-defined function type?
pub fn is_concrete_func(&self) -> bool {
matches!(self, HeapType::ConcreteFunc(_))
}
/// Get the underlying concrete, user-defined function type, if any.
///
/// Returns `None` if this is not a concrete function type.
pub fn as_concrete_func(&self) -> Option<&FuncType> {
match self {
HeapType::ConcreteFunc(f) => Some(f),
_ => None,
}
}
/// Get the underlying concrete, user-defined type, panicking if this is not
/// a concrete function type.
pub fn unwrap_concrete_func(&self) -> &FuncType {
self.as_concrete_func().unwrap()
}
/// Is this a concrete, user-defined array type?
pub fn is_concrete_array(&self) -> bool {
matches!(self, HeapType::ConcreteArray(_))
}
/// Get the underlying concrete, user-defined array type, if any.
///
/// Returns `None` for if this is not a concrete array type.
pub fn as_concrete_array(&self) -> Option<&ArrayType> {
match self {
HeapType::ConcreteArray(f) => Some(f),
_ => None,
}
}
/// Get the underlying concrete, user-defined type, panicking if this is not
/// a concrete array type.
pub fn unwrap_concrete_array(&self) -> &ArrayType {
self.as_concrete_array().unwrap()
}
/// Get the top type of this heap type's type hierarchy.
///
/// The returned heap type is a supertype of all types in this heap type's
/// type hierarchy.
#[inline]
pub fn top(&self) -> HeapType {
match self {
HeapType::Func | HeapType::ConcreteFunc(_) | HeapType::NoFunc => HeapType::Func,
HeapType::Extern => HeapType::Extern,
HeapType::Any
| HeapType::I31
| HeapType::Array
| HeapType::ConcreteArray(_)
| HeapType::None => HeapType::Any,
}
}
/// Is this the top type within its type hierarchy?
pub fn is_top(&self) -> bool {
match self {
HeapType::Any | HeapType::Extern | HeapType::Func => true,
_ => false,
}
}
/// Does this heap type match the other heap type?
///
/// That is, is this heap type a subtype of the other?
///
/// # Panics
///
/// Panics if either type is associated with a different engine from the
/// other.
pub fn matches(&self, other: &HeapType) -> bool {
match (self, other) {
(HeapType::Extern, HeapType::Extern) => true,
(HeapType::Extern, _) => false,
(HeapType::NoFunc, HeapType::NoFunc | HeapType::ConcreteFunc(_) | HeapType::Func) => {
true
}
(HeapType::NoFunc, _) => false,
(HeapType::ConcreteFunc(_), HeapType::Func) => true,
(HeapType::ConcreteFunc(a), HeapType::ConcreteFunc(b)) => a.matches(b),
(HeapType::ConcreteFunc(_), _) => false,
(HeapType::Func, HeapType::Func) => true,
(HeapType::Func, _) => false,
(
HeapType::None,
HeapType::None
| HeapType::ConcreteArray(_)
| HeapType::Array
| HeapType::I31
| HeapType::Any,
) => true,
(HeapType::None, _) => false,
(HeapType::ConcreteArray(_), HeapType::Array | HeapType::Any) => true,
(HeapType::ConcreteArray(a), HeapType::ConcreteArray(b)) => a.matches(b),
(HeapType::ConcreteArray(_), _) => false,
(HeapType::Array, HeapType::Array | HeapType::Any) => true,
(HeapType::Array, _) => false,
(HeapType::I31, HeapType::I31 | HeapType::Any) => true,
(HeapType::I31, _) => false,
(HeapType::Any, HeapType::Any) => true,
(HeapType::Any, _) => false,
}
}
/// Is heap type `a` precisely equal to heap type `b`?
///
/// Returns `false` even if `a` is a subtype of `b` or vice versa, if they
/// are not exactly the same heap type.
///
/// # Panics
///
/// Panics if either type is associated with a different engine from the
/// other.
pub fn eq(a: &HeapType, b: &HeapType) -> bool {
a.matches(b) && b.matches(a)
}
pub(crate) fn ensure_matches(&self, engine: &Engine, other: &HeapType) -> Result<()> {
if !self.comes_from_same_engine(engine) || !other.comes_from_same_engine(engine) {
bail!("type used with wrong engine");
}
if self.matches(other) {
Ok(())
} else {
bail!("type mismatch: expected {other}, found {self}");
}
}
pub(crate) fn comes_from_same_engine(&self, engine: &Engine) -> bool {
match self {
HeapType::Extern
| HeapType::Func
| HeapType::NoFunc
| HeapType::Any
| HeapType::I31
| HeapType::Array
| HeapType::None => true,
HeapType::ConcreteFunc(ty) => ty.comes_from_same_engine(engine),
HeapType::ConcreteArray(ty) => ty.comes_from_same_engine(engine),
}
}
pub(crate) fn to_wasm_type(&self) -> WasmHeapType {
match self {
HeapType::Extern => WasmHeapType::Extern,
HeapType::Func => WasmHeapType::Func,
HeapType::NoFunc => WasmHeapType::NoFunc,
HeapType::Any => WasmHeapType::Any,
HeapType::I31 => WasmHeapType::I31,
HeapType::Array => WasmHeapType::Array,
HeapType::None => WasmHeapType::None,
HeapType::ConcreteFunc(f) => {
WasmHeapType::ConcreteFunc(EngineOrModuleTypeIndex::Engine(f.type_index()))
}
HeapType::ConcreteArray(a) => {
WasmHeapType::ConcreteArray(EngineOrModuleTypeIndex::Engine(a.type_index()))
}
}
}
pub(crate) fn from_wasm_type(engine: &Engine, ty: &WasmHeapType) -> HeapType {
match ty {
WasmHeapType::Extern => HeapType::Extern,
WasmHeapType::Func => HeapType::Func,
WasmHeapType::NoFunc => HeapType::NoFunc,
WasmHeapType::Any => HeapType::Any,
WasmHeapType::I31 => HeapType::I31,
WasmHeapType::Array => HeapType::Array,
WasmHeapType::None => HeapType::None,
WasmHeapType::ConcreteFunc(EngineOrModuleTypeIndex::Engine(idx)) => {
HeapType::ConcreteFunc(FuncType::from_shared_type_index(engine, *idx))
}
WasmHeapType::ConcreteArray(EngineOrModuleTypeIndex::Engine(idx)) => {
HeapType::ConcreteArray(ArrayType::from_shared_type_index(engine, *idx))
}
WasmHeapType::ConcreteFunc(EngineOrModuleTypeIndex::Module(_))
| WasmHeapType::ConcreteFunc(EngineOrModuleTypeIndex::RecGroup(_))
| WasmHeapType::ConcreteArray(EngineOrModuleTypeIndex::Module(_))
| WasmHeapType::ConcreteArray(EngineOrModuleTypeIndex::RecGroup(_)) => {
panic!("HeapType::from_wasm_type on non-canonicalized-for-runtime-usage heap type")
}
}
}
pub(crate) fn as_registered_type(&self) -> Option<&RegisteredType> {
match self {
HeapType::ConcreteFunc(f) => Some(&f.registered_type),
HeapType::ConcreteArray(a) => Some(&a.registered_type),
HeapType::Extern
| HeapType::Func
| HeapType::NoFunc
| HeapType::Any
| HeapType::I31
| HeapType::Array
| HeapType::None => None,
}
}
#[inline]
pub(crate) fn is_vmgcref_type(&self) -> bool {
match self.top() {
Self::Any | Self::Extern => true,
Self::Func => false,
ty => unreachable!("not a top type: {ty:?}"),
}
}
/// Is this a `VMGcRef` type that is not i31 and is not an uninhabited
/// bottom type?
#[inline]
pub(crate) fn is_vmgcref_type_and_points_to_object(&self) -> bool {
self.is_vmgcref_type() && !matches!(self, HeapType::I31 | HeapType::NoFunc | HeapType::None)
}
}
// External Types
/// A list of all possible types which can be externally referenced from a
/// WebAssembly module.
///
/// This list can be found in [`ImportType`] or [`ExportType`], so these types
/// can either be imported or exported.
#[derive(Debug, Clone)]
pub enum ExternType {
/// This external type is the type of a WebAssembly function.
Func(FuncType),
/// This external type is the type of a WebAssembly global.
Global(GlobalType),
/// This external type is the type of a WebAssembly table.
Table(TableType),
/// This external type is the type of a WebAssembly memory.
Memory(MemoryType),
}
macro_rules! extern_type_accessors {
($(($variant:ident($ty:ty) $get:ident $unwrap:ident))*) => ($(
/// Attempt to return the underlying type of this external type,
/// returning `None` if it is a different type.
pub fn $get(&self) -> Option<&$ty> {
if let ExternType::$variant(e) = self {
Some(e)
} else {
None
}
}
/// Returns the underlying descriptor of this [`ExternType`], panicking
/// if it is a different type.
///
/// # Panics
///
/// Panics if `self` is not of the right type.
pub fn $unwrap(&self) -> &$ty {
self.$get().expect(concat!("expected ", stringify!($ty)))
}
)*)
}
impl ExternType {
extern_type_accessors! {
(Func(FuncType) func unwrap_func)
(Global(GlobalType) global unwrap_global)
(Table(TableType) table unwrap_table)
(Memory(MemoryType) memory unwrap_memory)
}
pub(crate) fn from_wasmtime(
engine: &Engine,
types: &ModuleTypes,
ty: &EntityType,
) -> ExternType {
match ty {
EntityType::Function(idx) => match idx {
EngineOrModuleTypeIndex::Engine(e) => {
FuncType::from_shared_type_index(engine, *e).into()
}
EngineOrModuleTypeIndex::Module(m) => {
FuncType::from_wasm_func_type(engine, types[*m].unwrap_func().clone()).into()
}
EngineOrModuleTypeIndex::RecGroup(_) => unreachable!(),
},
EntityType::Global(ty) => GlobalType::from_wasmtime_global(engine, ty).into(),
EntityType::Memory(ty) => MemoryType::from_wasmtime_memory(ty).into(),
EntityType::Table(ty) => TableType::from_wasmtime_table(engine, ty).into(),
EntityType::Tag(_) => unimplemented!("wasm tag support"),
}
}
}
impl From<FuncType> for ExternType {
fn from(ty: FuncType) -> ExternType {
ExternType::Func(ty)
}
}
impl From<GlobalType> for ExternType {
fn from(ty: GlobalType) -> ExternType {
ExternType::Global(ty)
}
}
impl From<MemoryType> for ExternType {
fn from(ty: MemoryType) -> ExternType {
ExternType::Memory(ty)
}
}
impl From<TableType> for ExternType {
fn from(ty: TableType) -> ExternType {
ExternType::Table(ty)
}
}
/// The storage type of a `struct` field or `array` element.
///
/// This is either a packed 8- or -16 bit integer, or else it is some unpacked
/// Wasm value type.
#[derive(Clone, Hash)]
pub enum StorageType {
/// `i8`, an 8-bit integer.
I8,
/// `i16`, a 16-bit integer.
I16,
/// A value type.
ValType(ValType),
}
impl From<ValType> for StorageType {
#[inline]
fn from(v: ValType) -> Self {
StorageType::ValType(v)
}
}
impl StorageType {
/// Is this an `i8`?
#[inline]
pub fn is_i8(&self) -> bool {
matches!(self, Self::I8)
}
/// Is this an `i16`?
#[inline]
pub fn is_i16(&self) -> bool {
matches!(self, Self::I16)
}
/// Is this a Wasm value type?
#[inline]
pub fn is_val_type(&self) -> bool {
matches!(self, Self::I16)
}
/// Get this storage type's underlying value type, if any.
///
/// Returns `None` if this storage type is not a value type.
#[inline]
pub fn as_val_type(&self) -> Option<&ValType> {
match self {
Self::ValType(v) => Some(v),
_ => None,
}
}
/// Get this storage type's underlying value type, panicking if it is not a
/// value type.
pub fn unwrap_val_type(&self) -> &ValType {
self.as_val_type().unwrap()
}
/// Does this field type match the other field type?
///
/// That is, is this field type a subtype of the other field type?
///
/// # Panics
///
/// Panics if either type is associated with a different engine from the
/// other.
pub fn matches(&self, other: &Self) -> bool {
match (self, other) {
(StorageType::I8, StorageType::I8) => true,
(StorageType::I8, _) => false,
(StorageType::I16, StorageType::I16) => true,
(StorageType::I16, _) => false,
(StorageType::ValType(a), StorageType::ValType(b)) => a.matches(b),
(StorageType::ValType(_), _) => false,
}
}
/// Is field type `a` precisely equal to field type `b`?
///
/// Returns `false` even if `a` is a subtype of `b` or vice versa, if they
/// are not exactly the same field type.
///
/// # Panics
///
/// Panics if either type is associated with a different engine from the
/// other.
pub fn eq(a: &Self, b: &Self) -> bool {
a.matches(b) && b.matches(a)
}
pub(crate) fn from_wasm_storage_type(engine: &Engine, ty: &WasmStorageType) -> Self {
match ty {
WasmStorageType::I8 => Self::I8,
WasmStorageType::I16 => Self::I16,
WasmStorageType::Val(v) => ValType::from_wasm_type(engine, &v).into(),
}
}
pub(crate) fn to_wasm_storage_type(&self) -> WasmStorageType {
match self {
Self::I8 => WasmStorageType::I8,
Self::I16 => WasmStorageType::I16,
Self::ValType(v) => WasmStorageType::Val(v.to_wasm_type()),
}
}
}
/// The type of a `struct` field or an `array`'s elements.
///
/// This is a pair of both the field's storage type and its mutability
/// (i.e. whether the field can be updated or not).
#[derive(Clone, Hash)]
pub struct FieldType {
mutability: Mutability,
element_type: StorageType,
}
impl FieldType {
/// Construct a new field type from the given parts.
#[inline]
pub fn new(mutability: Mutability, element_type: StorageType) -> Self {
Self {
mutability,
element_type,
}
}
/// Get whether or not this field type is mutable.
#[inline]
pub fn mutability(&self) -> Mutability {
self.mutability
}
/// Get this field type's storage type.
#[inline]
pub fn element_type(&self) -> &StorageType {
&self.element_type
}
/// Does this field type match the other field type?
///
/// That is, is this field type a subtype of the other field type?
///
/// # Panics
///
/// Panics if either type is associated with a different engine from the
/// other.
pub fn matches(&self, other: &Self) -> bool {
(other.mutability == Mutability::Var || self.mutability == Mutability::Const)
&& self.element_type.matches(&other.element_type)
}
/// Is field type `a` precisely equal to field type `b`?
///
/// Returns `false` even if `a` is a subtype of `b` or vice versa, if they
/// are not exactly the same field type.
///
/// # Panics
///
/// Panics if either type is associated with a different engine from the
/// other.
pub fn eq(a: &Self, b: &Self) -> bool {
a.matches(b) && b.matches(a)
}
pub(crate) fn from_wasm_field_type(engine: &Engine, ty: &WasmFieldType) -> Self {
Self {
mutability: if ty.mutable {
Mutability::Var
} else {
Mutability::Const
},
element_type: StorageType::from_wasm_storage_type(engine, &ty.element_type),
}
}
pub(crate) fn to_wasm_field_type(&self) -> WasmFieldType {
WasmFieldType {
element_type: self.element_type.to_wasm_storage_type(),
mutable: matches!(self.mutability, Mutability::Var),
}
}
}
/// The type of a WebAssembly array.
///
/// WebAssembly arrays are dynamically-sized, but not resizable. They contain
/// either unpacked [`Val`][crate::Val]s or packed 8-/16-bit integers.
///
/// # Subtyping and Equality
///
/// `ArrayType` does not implement `Eq`, because reference types have a
/// subtyping relationship, and so 99.99% of the time you actually want to check
/// whether one type matches (i.e. is a subtype of) another type. You can use
/// the [`ArrayType::matches`] method to perform these types of checks. If,
/// however, you are in that 0.01% scenario where you need to check precise
/// equality between types, you can use the [`ArrayType::eq`] method.
//
// TODO: Once we have array values, update above docs with a reference to the
// future `Array::matches_ty` method
#[derive(Debug, Clone, Hash)]
pub struct ArrayType {
registered_type: RegisteredType,
}
impl ArrayType {
/// Construct a new `ArrayType` with the given field type's mutability and
/// storage type.
///
/// The result will be associated with the given engine, and attempts to use
/// it with other engines will panic (for example, checking whether it is a
/// subtype of another array type that is associated with a different
/// engine).
pub fn new(engine: &Engine, field_type: FieldType) -> Self {
// Same as in `FuncType::new`: we must prevent any `RegisteredType` in
// `field_type` from being reclaimed while constructing this array type.
let _registration = field_type
.element_type
.as_val_type()
.and_then(|v| v.as_ref())
.and_then(|r| r.heap_type().as_registered_type());
let wasm_ty = WasmArrayType(field_type.to_wasm_field_type());
Self::from_wasm_array_type(engine, wasm_ty)
}
/// Get the engine that this array type is associated with.
pub fn engine(&self) -> &Engine {
self.registered_type.engine()
}
/// Get this array's underlying field type.
///
/// The field type contains information about both this array type's
/// mutability and the storage type used for its elements.
pub fn field_type(&self) -> FieldType {
FieldType::from_wasm_field_type(self.engine(), &self.as_wasm_array_type().0)
}
/// Get this array type's mutability and whether its instances' elements can
/// be updated or not.
///
/// This is a convenience method providing a short-hand for
/// `my_array_type.field_type().mutability()`.
pub fn mutability(&self) -> Mutability {
if self.as_wasm_array_type().0.mutable {
Mutability::Var
} else {
Mutability::Const
}
}
/// Get the storage type used for this array type's elements.
///
/// This is a convenience method providing a short-hand for
/// `my_array_type.field_type().element_type()`.
pub fn element_type(&self) -> StorageType {
StorageType::from_wasm_storage_type(
self.engine(),
&self.registered_type.unwrap_array().0.element_type,
)
}
/// Does this array type match the other array type?
///
/// That is, is this function type a subtype of the other array type?
///
/// # Panics
///
/// Panics if either type is associated with a different engine from the
/// other.
pub fn matches(&self, other: &ArrayType) -> bool {
assert!(self.comes_from_same_engine(other.engine()));
// Avoid matching on structure for subtyping checks when we have
// precisely the same type.
if self.type_index() == other.type_index() {
return true;
}
self.field_type().matches(&other.field_type())
}
/// Is array type `a` precisely equal to array type `b`?
///
/// Returns `false` even if `a` is a subtype of `b` or vice versa, if they
/// are not exactly the same array type.
///
/// # Panics
///
/// Panics if either type is associated with a different engine from the
/// other.
pub fn eq(a: &ArrayType, b: &ArrayType) -> bool {
assert!(a.comes_from_same_engine(b.engine()));
a.type_index() == b.type_index()
}
pub(crate) fn comes_from_same_engine(&self, engine: &Engine) -> bool {
Engine::same(self.registered_type.engine(), engine)
}
pub(crate) fn type_index(&self) -> VMSharedTypeIndex {
self.registered_type.index()
}
pub(crate) fn as_wasm_array_type(&self) -> &WasmArrayType {
self.registered_type.unwrap_array()
}
/// Construct a `ArrayType` from a `WasmArrayType`.
///
/// This method should only be used when something has already registered --
/// and is *keeping registered* -- any other concrete Wasm types referenced
/// by the given `WasmArrayType`.
///
/// For example, this method may be called to convert an array type from
/// within a Wasm module's `ModuleTypes` since the Wasm module itself is
/// holding a strong reference to all of its types, including any `(ref null
/// <index>)` types used as the element type for this array type.
pub(crate) fn from_wasm_array_type(engine: &Engine, ty: WasmArrayType) -> ArrayType {
let ty = RegisteredType::new(
engine,
WasmSubType {
// TODO:
//
// is_final: true,
// supertype: None,
composite_type: WasmCompositeType::Array(ty),
},
);
Self {
registered_type: ty,
}
}
pub(crate) fn from_shared_type_index(engine: &Engine, index: VMSharedTypeIndex) -> ArrayType {
let ty = RegisteredType::root(engine, index).expect(
"VMSharedTypeIndex is not registered in the Engine! Wrong \
engine? Didn't root the index somewhere?",
);
assert!(ty.is_array());
Self {
registered_type: ty,
}
}
}
/// The type of a WebAssembly function.
///
/// WebAssembly functions can have 0 or more parameters and results.
///
/// # Subtyping and Equality
///
/// `FuncType` does not implement `Eq`, because reference types have a subtyping
/// relationship, and so 99.99% of the time you actually want to check whether
/// one type matches (i.e. is a subtype of) another type. You can use the
/// [`FuncType::matches`] and [`Func::matches_ty`][crate::Func::matches_ty]
/// methods to perform these types of checks. If, however, you are in that 0.01%
/// scenario where you need to check precise equality between types, you can use
/// the [`FuncType::eq`] method.
#[derive(Debug, Clone, Hash)]
pub struct FuncType {
registered_type: RegisteredType,
}
impl Display for FuncType {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "(type (func")?;
if self.params().len() > 0 {
write!(f, " (param")?;
for p in self.params() {
write!(f, " {p}")?;
}
write!(f, ")")?;
}
if self.results().len() > 0 {
write!(f, " (result")?;
for r in self.results() {
write!(f, " {r}")?;
}
write!(f, ")")?;
}
write!(f, "))")
}
}
impl FuncType {
/// Creates a new function descriptor from the given parameters and results.
///
/// The function descriptor returned will represent a function which takes
/// `params` as arguments and returns `results` when it is finished.
pub fn new(
engine: &Engine,
params: impl IntoIterator<Item = ValType>,
results: impl IntoIterator<Item = ValType>,
) -> FuncType {
// Keep any of our parameters' and results' `RegisteredType`s alive
// across `Self::from_wasm_func_type`. If one of our given `ValType`s is
// the only thing keeping a type in the registry, we don't want to
// unregister it when we convert the `ValType` into a `WasmValType` just
// before we register our new `WasmFuncType` that will reference it.
let mut registrations = smallvec::SmallVec::<[_; 4]>::new();
let mut to_wasm_type = |ty: ValType| {
if let Some(r) = ty.as_ref() {
if let Some(r) = r.heap_type().as_registered_type() {
registrations.push(r.clone());
}
}
ty.to_wasm_type()
};
Self::from_wasm_func_type(
engine,
WasmFuncType::new(
params.into_iter().map(&mut to_wasm_type).collect(),
results.into_iter().map(&mut to_wasm_type).collect(),
),
)
}
/// Get the engine that this function type is associated with.
pub fn engine(&self) -> &Engine {
self.registered_type.engine()
}
/// Get the `i`th parameter type.
///
/// Returns `None` if `i` is out of bounds.
pub fn param(&self, i: usize) -> Option<ValType> {
let engine = self.engine();
self.registered_type
.unwrap_func()
.params()
.get(i)
.map(|ty| ValType::from_wasm_type(engine, ty))
}
/// Returns the list of parameter types for this function.
#[inline]
pub fn params(&self) -> impl ExactSizeIterator<Item = ValType> + '_ {
let engine = self.engine();
self.registered_type
.unwrap_func()
.params()
.iter()
.map(|ty| ValType::from_wasm_type(engine, ty))
}
/// Get the `i`th result type.
///
/// Returns `None` if `i` is out of bounds.
pub fn result(&self, i: usize) -> Option<ValType> {
let engine = self.engine();
self.registered_type
.unwrap_func()
.returns()
.get(i)
.map(|ty| ValType::from_wasm_type(engine, ty))
}
/// Returns the list of result types for this function.
#[inline]
pub fn results(&self) -> impl ExactSizeIterator<Item = ValType> + '_ {
let engine = self.engine();
self.registered_type
.unwrap_func()
.returns()
.iter()
.map(|ty| ValType::from_wasm_type(engine, ty))
}
/// Does this function type match the other function type?
///
/// That is, is this function type a subtype of the other function type?
///
/// # Panics
///
/// Panics if either type is associated with a different engine from the
/// other.
pub fn matches(&self, other: &FuncType) -> bool {
assert!(self.comes_from_same_engine(other.engine()));
// Avoid matching on structure for subtyping checks when we have
// precisely the same type.
if self.type_index() == other.type_index() {
return true;
}
self.params().len() == other.params().len()
&& self.results().len() == other.results().len()
// Params are contravariant and results are covariant. For more
// details and a refresher on variance, read
// https://github.com/bytecodealliance/wasm-tools/blob/f1d89a4/crates/wasmparser/src/readers/core/types/matches.rs#L137-L174
&& self
.params()
.zip(other.params())
.all(|(a, b)| b.matches(&a))
&& self
.results()
.zip(other.results())
.all(|(a, b)| a.matches(&b))
}
/// Is function type `a` precisely equal to function type `b`?
///
/// Returns `false` even if `a` is a subtype of `b` or vice versa, if they
/// are not exactly the same function type.
///
/// # Panics
///
/// Panics if either type is associated with a different engine from the
/// other.
pub fn eq(a: &FuncType, b: &FuncType) -> bool {
assert!(a.comes_from_same_engine(b.engine()));
a.type_index() == b.type_index()
}
pub(crate) fn comes_from_same_engine(&self, engine: &Engine) -> bool {
Engine::same(self.registered_type.engine(), engine)
}
pub(crate) fn type_index(&self) -> VMSharedTypeIndex {
self.registered_type.index()
}
pub(crate) fn as_wasm_func_type(&self) -> &WasmFuncType {
self.registered_type.unwrap_func()
}
pub(crate) fn into_registered_type(self) -> RegisteredType {
self.registered_type
}
/// Construct a `FuncType` from a `WasmFuncType`.
///
/// This method should only be used when something has already registered --
/// and is *keeping registered* -- any other concrete Wasm types referenced
/// by the given `WasmFuncType`.
///
/// For example, this method may be called to convert a function type from
/// within a Wasm module's `ModuleTypes` since the Wasm module itself is
/// holding a strong reference to all of its types, including any `(ref null
/// <index>)` types used in the function's parameters and results.
pub(crate) fn from_wasm_func_type(engine: &Engine, ty: WasmFuncType) -> FuncType {
let ty = RegisteredType::new(
engine,
WasmSubType {
// TODO:
//
// is_final: true,
// supertype: None,
composite_type: WasmCompositeType::Func(ty),
},
);
Self {
registered_type: ty,
}
}
pub(crate) fn from_shared_type_index(engine: &Engine, index: VMSharedTypeIndex) -> FuncType {
let ty = RegisteredType::root(engine, index).expect(
"VMSharedTypeIndex is not registered in the Engine! Wrong \
engine? Didn't root the index somewhere?",
);
assert!(ty.is_func());
Self {
registered_type: ty,
}
}
}
// Global Types
/// A WebAssembly global descriptor.
///
/// This type describes an instance of a global in a WebAssembly module. Globals
/// are local to an [`Instance`](crate::Instance) and are either immutable or
/// mutable.
#[derive(Debug, Clone, Hash)]
pub struct GlobalType {
content: ValType,
mutability: Mutability,
}
impl GlobalType {
/// Creates a new global descriptor of the specified `content` type and
/// whether or not it's mutable.
pub fn new(content: ValType, mutability: Mutability) -> GlobalType {
GlobalType {
content,
mutability,
}
}
/// Returns the value type of this global descriptor.
pub fn content(&self) -> &ValType {
&self.content
}
/// Returns whether or not this global is mutable.
pub fn mutability(&self) -> Mutability {
self.mutability
}
pub(crate) fn to_wasm_type(&self) -> Global {
let wasm_ty = self.content().to_wasm_type();
let mutability = matches!(self.mutability(), Mutability::Var);
Global {
wasm_ty,
mutability,
}
}
/// Returns `None` if the wasmtime global has a type that we can't
/// represent, but that should only very rarely happen and indicate a bug.
pub(crate) fn from_wasmtime_global(engine: &Engine, global: &Global) -> GlobalType {
let ty = ValType::from_wasm_type(engine, &global.wasm_ty);
let mutability = if global.mutability {
Mutability::Var
} else {
Mutability::Const
};
GlobalType::new(ty, mutability)
}
}
// Table Types
/// A descriptor for a table in a WebAssembly module.
///
/// Tables are contiguous chunks of a specific element, typically a `funcref` or
/// an `externref`. The most common use for tables is a function table through
/// which `call_indirect` can invoke other functions.
#[derive(Debug, Clone, Hash)]
pub struct TableType {
// Keep a `wasmtime::RefType` so that `TableType::element` doesn't need to
// take an `&Engine`.
element: RefType,
ty: Table,
}
impl TableType {
/// Creates a new table descriptor which will contain the specified
/// `element` and have the `limits` applied to its length.
pub fn new(element: RefType, min: u32, max: Option<u32>) -> TableType {
let wasm_ty = element.to_wasm_type();
debug_assert!(
wasm_ty.is_canonicalized_for_runtime_usage(),
"should be canonicalized for runtime usage: {wasm_ty:?}"
);
TableType {
element,
ty: Table {
wasm_ty,
minimum: min,
maximum: max,
},
}
}
/// Returns the element value type of this table.
pub fn element(&self) -> &RefType {
&self.element
}
/// Returns minimum number of elements this table must have
pub fn minimum(&self) -> u32 {
self.ty.minimum
}
/// Returns the optionally-specified maximum number of elements this table
/// can have.
///
/// If this returns `None` then the table is not limited in size.
pub fn maximum(&self) -> Option<u32> {
self.ty.maximum
}
pub(crate) fn from_wasmtime_table(engine: &Engine, table: &Table) -> TableType {
let element = RefType::from_wasm_type(engine, &table.wasm_ty);
TableType {
element,
ty: table.clone(),
}
}
pub(crate) fn wasmtime_table(&self) -> &Table {
&self.ty
}
}
// Memory Types
/// A descriptor for a WebAssembly memory type.
///
/// Memories are described in units of pages (64KB) and represent contiguous
/// chunks of addressable memory.
#[derive(Debug, Clone, Hash, Eq, PartialEq)]
pub struct MemoryType {
ty: Memory,
}
impl MemoryType {
/// Creates a new descriptor for a 32-bit WebAssembly memory given the
/// specified limits of the memory.
///
/// The `minimum` and `maximum` values here are specified in units of
/// WebAssembly pages, which are 64k.
pub fn new(minimum: u32, maximum: Option<u32>) -> MemoryType {
MemoryType {
ty: Memory {
memory64: false,
shared: false,
minimum: minimum.into(),
maximum: maximum.map(|i| i.into()),
},
}
}
/// Creates a new descriptor for a 64-bit WebAssembly memory given the
/// specified limits of the memory.
///
/// The `minimum` and `maximum` values here are specified in units of
/// WebAssembly pages, which are 64k.
///
/// Note that 64-bit memories are part of the memory64 proposal for
/// WebAssembly which is not standardized yet.
pub fn new64(minimum: u64, maximum: Option<u64>) -> MemoryType {
MemoryType {
ty: Memory {
memory64: true,
shared: false,
minimum,
maximum,
},
}
}
/// Creates a new descriptor for shared WebAssembly memory given the
/// specified limits of the memory.
///
/// The `minimum` and `maximum` values here are specified in units of
/// WebAssembly pages, which are 64k.
///
/// Note that shared memories are part of the threads proposal for
/// WebAssembly which is not standardized yet.
pub fn shared(minimum: u32, maximum: u32) -> MemoryType {
MemoryType {
ty: Memory {
memory64: false,
shared: true,
minimum: minimum.into(),
maximum: Some(maximum.into()),
},
}
}
/// Returns whether this is a 64-bit memory or not.
///
/// Note that 64-bit memories are part of the memory64 proposal for
/// WebAssembly which is not standardized yet.
pub fn is_64(&self) -> bool {
self.ty.memory64
}
/// Returns whether this is a shared memory or not.
///
/// Note that shared memories are part of the threads proposal for
/// WebAssembly which is not standardized yet.
pub fn is_shared(&self) -> bool {
self.ty.shared
}
/// Returns minimum number of WebAssembly pages this memory must have.
///
/// Note that the return value, while a `u64`, will always fit into a `u32`
/// for 32-bit memories.
pub fn minimum(&self) -> u64 {
self.ty.minimum
}
/// Returns the optionally-specified maximum number of pages this memory
/// can have.
///
/// If this returns `None` then the memory is not limited in size.
///
/// Note that the return value, while a `u64`, will always fit into a `u32`
/// for 32-bit memories.
pub fn maximum(&self) -> Option<u64> {
self.ty.maximum
}
pub(crate) fn from_wasmtime_memory(memory: &Memory) -> MemoryType {
MemoryType { ty: memory.clone() }
}
pub(crate) fn wasmtime_memory(&self) -> &Memory {
&self.ty
}
}
// Import Types
/// A descriptor for an imported value into a wasm module.
///
/// This type is primarily accessed from the
/// [`Module::imports`](crate::Module::imports) API. Each [`ImportType`]
/// describes an import into the wasm module with the module/name that it's
/// imported from as well as the type of item that's being imported.
#[derive(Clone)]
pub struct ImportType<'module> {
/// The module of the import.
module: &'module str,
/// The field of the import.
name: &'module str,
/// The type of the import.
ty: EntityType,
types: &'module ModuleTypes,
engine: &'module Engine,
}
impl<'module> ImportType<'module> {
/// Creates a new import descriptor which comes from `module` and `name` and
/// is of type `ty`.
pub(crate) fn new(
module: &'module str,
name: &'module str,
ty: EntityType,
types: &'module ModuleTypes,
engine: &'module Engine,
) -> ImportType<'module> {
ImportType {
module,
name,
ty,
types,
engine,
}
}
/// Returns the module name that this import is expected to come from.
pub fn module(&self) -> &'module str {
self.module
}
/// Returns the field name of the module that this import is expected to
/// come from.
pub fn name(&self) -> &'module str {
self.name
}
/// Returns the expected type of this import.
pub fn ty(&self) -> ExternType {
ExternType::from_wasmtime(self.engine, self.types, &self.ty)
}
}
impl<'module> fmt::Debug for ImportType<'module> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
f.debug_struct("ImportType")
.field("module", &self.module())
.field("name", &self.name())
.field("ty", &self.ty())
.finish()
}
}
// Export Types
/// A descriptor for an exported WebAssembly value.
///
/// This type is primarily accessed from the
/// [`Module::exports`](crate::Module::exports) accessor and describes what
/// names are exported from a wasm module and the type of the item that is
/// exported.
#[derive(Clone)]
pub struct ExportType<'module> {
/// The name of the export.
name: &'module str,
/// The type of the export.
ty: EntityType,
types: &'module ModuleTypes,
engine: &'module Engine,
}
impl<'module> ExportType<'module> {
/// Creates a new export which is exported with the given `name` and has the
/// given `ty`.
pub(crate) fn new(
name: &'module str,
ty: EntityType,
types: &'module ModuleTypes,
engine: &'module Engine,
) -> ExportType<'module> {
ExportType {
name,
ty,
types,
engine,
}
}
/// Returns the name by which this export is known.
pub fn name(&self) -> &'module str {
self.name
}
/// Returns the type of this export.
pub fn ty(&self) -> ExternType {
ExternType::from_wasmtime(self.engine, self.types, &self.ty)
}
}
impl<'module> fmt::Debug for ExportType<'module> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
f.debug_struct("ExportType")
.field("name", &self.name().to_owned())
.field("ty", &self.ty())
.finish()
}
}