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mod aliases;
mod builder;
mod canonicals;
mod components;
mod exports;
mod imports;
mod instances;
mod modules;
mod names;
mod start;
mod types;
pub use self::aliases::*;
pub use self::builder::*;
pub use self::canonicals::*;
pub use self::components::*;
pub use self::exports::*;
pub use self::imports::*;
pub use self::instances::*;
pub use self::modules::*;
pub use self::names::*;
pub use self::start::*;
pub use self::types::*;
use crate::{CustomSection, Encode, ProducersSection, RawCustomSection};
// Core sorts extended by the component model
const CORE_TYPE_SORT: u8 = 0x10;
const CORE_MODULE_SORT: u8 = 0x11;
const CORE_INSTANCE_SORT: u8 = 0x12;
const CORE_SORT: u8 = 0x00;
const FUNCTION_SORT: u8 = 0x01;
const VALUE_SORT: u8 = 0x02;
const TYPE_SORT: u8 = 0x03;
const COMPONENT_SORT: u8 = 0x04;
const INSTANCE_SORT: u8 = 0x05;
/// A WebAssembly component section.
///
/// Various builders defined in this crate already implement this trait, but you
/// can also implement it yourself for your own custom section builders, or use
/// `RawSection` to use a bunch of raw bytes as a section.
pub trait ComponentSection: Encode {
/// Gets the section identifier for this section.
fn id(&self) -> u8;
/// Appends this section to the specified destination list of bytes.
fn append_to_component(&self, dst: &mut Vec<u8>) {
dst.push(self.id());
self.encode(dst);
}
}
/// Known section identifiers of WebAssembly components.
///
/// These sections are supported by the component model proposal.
#[derive(Clone, Copy, Debug, Eq, PartialEq, Ord, PartialOrd)]
#[repr(u8)]
pub enum ComponentSectionId {
/// The section is a core custom section.
CoreCustom = 0,
/// The section is a core module section.
CoreModule = 1,
/// The section is a core instance section.
CoreInstance = 2,
/// The section is a core type section.
CoreType = 3,
/// The section is a component section.
Component = 4,
/// The section is an instance section.
Instance = 5,
/// The section is an alias section.
Alias = 6,
/// The section is a type section.
Type = 7,
/// The section is a canonical function section.
CanonicalFunction = 8,
/// The section is a start section.
Start = 9,
/// The section is an import section.
Import = 10,
/// The section is an export section.
Export = 11,
}
impl From<ComponentSectionId> for u8 {
#[inline]
fn from(id: ComponentSectionId) -> u8 {
id as u8
}
}
impl Encode for ComponentSectionId {
fn encode(&self, sink: &mut Vec<u8>) {
sink.push(*self as u8);
}
}
/// Represents a WebAssembly component that is being encoded.
///
/// Unlike core WebAssembly modules, the sections of a component
/// may appear in any order and may be repeated.
///
/// Components may also added as a section to other components.
#[derive(Clone, Debug)]
pub struct Component {
bytes: Vec<u8>,
}
impl Component {
/// The 8-byte header at the beginning of all components.
#[rustfmt::skip]
pub const HEADER: [u8; 8] = [
// Magic
0x00, 0x61, 0x73, 0x6D,
// Version
0x0d, 0x00, 0x01, 0x00,
];
/// Begin writing a new `Component`.
pub fn new() -> Self {
Self {
bytes: Self::HEADER.to_vec(),
}
}
/// Finish writing this component and extract ownership of the encoded bytes.
pub fn finish(self) -> Vec<u8> {
self.bytes
}
/// Write a section to this component.
pub fn section(&mut self, section: &impl ComponentSection) -> &mut Self {
self.bytes.push(section.id());
section.encode(&mut self.bytes);
self
}
/// View the encoded bytes.
pub fn as_slice(&self) -> &[u8] {
&self.bytes
}
}
impl Default for Component {
fn default() -> Self {
Self::new()
}
}
impl ComponentSection for CustomSection<'_> {
fn id(&self) -> u8 {
ComponentSectionId::CoreCustom.into()
}
}
impl ComponentSection for RawCustomSection<'_> {
fn id(&self) -> u8 {
ComponentSectionId::CoreCustom.into()
}
}
impl ComponentSection for ProducersSection {
fn id(&self) -> u8 {
ComponentSectionId::CoreCustom.into()
}
}