1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129
use super::{
COMPONENT_SORT, CORE_MODULE_SORT, CORE_SORT, FUNCTION_SORT, INSTANCE_SORT, TYPE_SORT,
VALUE_SORT,
};
use crate::{encode_section, ComponentSection, ComponentSectionId, ComponentTypeRef, Encode};
/// Represents the kind of an export from a WebAssembly component.
#[derive(Clone, Copy, Debug, Eq, PartialEq)]
pub enum ComponentExportKind {
/// The export is a core module.
Module,
/// The export is a function.
Func,
/// The export is a value.
Value,
/// The export is a type.
Type,
/// The export is an instance.
Instance,
/// The export is a component.
Component,
}
impl Encode for ComponentExportKind {
fn encode(&self, sink: &mut Vec<u8>) {
match self {
Self::Module => {
sink.push(CORE_SORT);
sink.push(CORE_MODULE_SORT);
}
Self::Func => {
sink.push(FUNCTION_SORT);
}
Self::Value => {
sink.push(VALUE_SORT);
}
Self::Type => {
sink.push(TYPE_SORT);
}
Self::Instance => {
sink.push(INSTANCE_SORT);
}
Self::Component => {
sink.push(COMPONENT_SORT);
}
}
}
}
/// An encoder for the export section of WebAssembly component.
///
/// # Example
///
/// ```rust
/// use wasm_encoder::{Component, ComponentExportSection, ComponentExportKind};
///
/// // This exports a function named "foo"
/// let mut exports = ComponentExportSection::new();
/// exports.export("foo", ComponentExportKind::Func, 0, None);
///
/// let mut component = Component::new();
/// component.section(&exports);
///
/// let bytes = component.finish();
/// ```
#[derive(Clone, Debug, Default)]
pub struct ComponentExportSection {
bytes: Vec<u8>,
num_added: u32,
}
impl ComponentExportSection {
/// Create a new component export section encoder.
pub fn new() -> Self {
Self::default()
}
/// The number of exports in the section.
pub fn len(&self) -> u32 {
self.num_added
}
/// Determines if the section is empty.
pub fn is_empty(&self) -> bool {
self.num_added == 0
}
/// Define an export in the export section.
pub fn export(
&mut self,
name: &str,
kind: ComponentExportKind,
index: u32,
ty: Option<ComponentTypeRef>,
) -> &mut Self {
crate::encode_component_export_name(&mut self.bytes, name);
kind.encode(&mut self.bytes);
index.encode(&mut self.bytes);
match ty {
Some(ty) => {
self.bytes.push(0x01);
ty.encode(&mut self.bytes);
}
None => {
self.bytes.push(0x00);
}
}
self.num_added += 1;
self
}
}
impl Encode for ComponentExportSection {
fn encode(&self, sink: &mut Vec<u8>) {
encode_section(sink, self.num_added, &self.bytes);
}
}
impl ComponentSection for ComponentExportSection {
fn id(&self) -> u8 {
ComponentSectionId::Export.into()
}
}
/// For more information on this see `encode_component_import_name`.
pub(crate) fn encode_component_export_name(bytes: &mut Vec<u8>, name: &str) {
bytes.push(0x00);
name.encode(bytes);
}