wasm_encoder/core/
exports.rs

1use super::{
2    CORE_FUNCTION_SORT, CORE_GLOBAL_SORT, CORE_MEMORY_SORT, CORE_TABLE_SORT, CORE_TAG_SORT,
3};
4use crate::{encode_section, Encode, Section, SectionId};
5use alloc::vec::Vec;
6
7/// Represents the kind of an export from a WebAssembly module.
8#[derive(Clone, Copy, Debug, Eq, PartialEq, Hash)]
9#[repr(u8)]
10pub enum ExportKind {
11    /// The export is a function.
12    Func = CORE_FUNCTION_SORT,
13    /// The export is a table.
14    Table = CORE_TABLE_SORT,
15    /// The export is a memory.
16    Memory = CORE_MEMORY_SORT,
17    /// The export is a global.
18    Global = CORE_GLOBAL_SORT,
19    /// The export is a tag.
20    Tag = CORE_TAG_SORT,
21}
22
23impl Encode for ExportKind {
24    fn encode(&self, sink: &mut Vec<u8>) {
25        sink.push(*self as u8);
26    }
27}
28
29/// An encoder for the export section of WebAssembly module.
30///
31/// # Example
32///
33/// ```rust
34/// use wasm_encoder::{Module, ExportSection, ExportKind};
35///
36/// let mut exports = ExportSection::new();
37/// exports.export("foo", ExportKind::Func, 0);
38///
39/// let mut module = Module::new();
40/// module.section(&exports);
41///
42/// let bytes = module.finish();
43/// ```
44#[derive(Clone, Debug, Default)]
45pub struct ExportSection {
46    bytes: Vec<u8>,
47    num_added: u32,
48}
49
50impl ExportSection {
51    /// Create a new export section encoder.
52    pub fn new() -> Self {
53        Self::default()
54    }
55
56    /// The number of exports in the section.
57    pub fn len(&self) -> u32 {
58        self.num_added
59    }
60
61    /// Determines if the section is empty.
62    pub fn is_empty(&self) -> bool {
63        self.num_added == 0
64    }
65
66    /// Define an export in the export section.
67    pub fn export(&mut self, name: &str, kind: ExportKind, index: u32) -> &mut Self {
68        name.encode(&mut self.bytes);
69        kind.encode(&mut self.bytes);
70        index.encode(&mut self.bytes);
71        self.num_added += 1;
72        self
73    }
74}
75
76impl Encode for ExportSection {
77    fn encode(&self, sink: &mut Vec<u8>) {
78        encode_section(sink, self.num_added, &self.bytes);
79    }
80}
81
82impl Section for ExportSection {
83    fn id(&self) -> u8 {
84        SectionId::Export.into()
85    }
86}
wasm_encoder/core/exports.rs

wasm_encoder/core/
exports.rs
