wasmtime_c_api/types/
global.rs

1use crate::{wasm_externtype_t, wasm_valtype_t, CExternType};
2use std::cell::OnceCell;
3use wasmtime::GlobalType;
4
5pub type wasm_mutability_t = u8;
6
7pub const WASM_CONST: wasm_mutability_t = 0;
8pub const WASM_VAR: wasm_mutability_t = 1;
9
10#[repr(transparent)]
11#[derive(Clone)]
12pub struct wasm_globaltype_t {
13    ext: wasm_externtype_t,
14}
15
16wasmtime_c_api_macros::declare_ty!(wasm_globaltype_t);
17
18#[derive(Clone)]
19pub(crate) struct CGlobalType {
20    pub(crate) ty: GlobalType,
21    content_cache: OnceCell<wasm_valtype_t>,
22}
23
24impl wasm_globaltype_t {
25    pub(crate) fn new(ty: GlobalType) -> wasm_globaltype_t {
26        wasm_globaltype_t {
27            ext: wasm_externtype_t::from_extern_type(ty.into()),
28        }
29    }
30
31    pub(crate) fn try_from(e: &wasm_externtype_t) -> Option<&wasm_globaltype_t> {
32        match &e.which {
33            CExternType::Global(_) => Some(unsafe { &*(e as *const _ as *const _) }),
34            _ => None,
35        }
36    }
37
38    pub(crate) fn ty(&self) -> &CGlobalType {
39        match &self.ext.which {
40            CExternType::Global(f) => &f,
41            _ => unsafe { std::hint::unreachable_unchecked() },
42        }
43    }
44}
45
46impl CGlobalType {
47    pub(crate) fn new(ty: GlobalType) -> CGlobalType {
48        CGlobalType {
49            ty,
50            content_cache: OnceCell::new(),
51        }
52    }
53}
54
55#[unsafe(no_mangle)]
56pub extern "C" fn wasm_globaltype_new(
57    ty: Box<wasm_valtype_t>,
58    mutability: wasm_mutability_t,
59) -> Option<Box<wasm_globaltype_t>> {
60    use wasmtime::Mutability::*;
61    let mutability = match mutability {
62        WASM_CONST => Const,
63        WASM_VAR => Var,
64        _ => return None,
65    };
66    let ty = GlobalType::new(ty.ty.clone(), mutability);
67    Some(Box::new(wasm_globaltype_t::new(ty)))
68}
69
70#[unsafe(no_mangle)]
71pub extern "C" fn wasm_globaltype_content(gt: &wasm_globaltype_t) -> &wasm_valtype_t {
72    let gt = gt.ty();
73    gt.content_cache.get_or_init(|| wasm_valtype_t {
74        ty: gt.ty.content().clone(),
75    })
76}
77
78#[unsafe(no_mangle)]
79pub extern "C" fn wasm_globaltype_mutability(gt: &wasm_globaltype_t) -> wasm_mutability_t {
80    use wasmtime::Mutability::*;
81    let gt = gt.ty();
82    match gt.ty.mutability() {
83        Const => WASM_CONST,
84        Var => WASM_VAR,
85    }
86}
87
88#[unsafe(no_mangle)]
89pub extern "C" fn wasm_globaltype_as_externtype(ty: &wasm_globaltype_t) -> &wasm_externtype_t {
90    &ty.ext
91}
92
93#[unsafe(no_mangle)]
94pub extern "C" fn wasm_globaltype_as_externtype_const(
95    ty: &wasm_globaltype_t,
96) -> &wasm_externtype_t {
97    &ty.ext
98}
wasmtime_c_api/types/global.rs

wasmtime_c_api/types/
global.rs
