wasmer 7.1.0

High-performance WebAssembly runtime
Documentation 
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

pub(crate) mod extref;
pub use extref::*;

use wasmer_types::ExternType;

use crate::{
    AsStoreMut, AsStoreRef, ExportError, Exportable, Function, Global, Memory, Table, Tag,
    vm::VMExtern,
};

/// Trait convert a VMExtern to a Extern
pub trait VMExternToExtern {
    /// Convert to [`Extern`]
    fn to_extern(self, store: &mut impl AsStoreMut) -> Extern;
}

/// An `Extern` is the runtime representation of an entity that
/// can be imported or exported.
///
/// Spec: <https://webassembly.github.io/spec/core/exec/runtime.html#external-values>
#[derive(Clone, PartialEq, Eq)]
#[cfg_attr(feature = "artifact-size", derive(loupe::MemoryUsage))]
pub enum Extern {
    /// An external [`Function`].
    Function(Function),
    /// An external [`Global`].
    Global(Global),
    /// An external [`Table`].
    Table(Table),
    /// An external [`Memory`].
    Memory(Memory),
    /// An external [`Memory`].
    Tag(Tag),
}

impl Extern {
    /// Return the underlying type of the inner `Extern`.
    pub fn ty(&self, store: &impl AsStoreRef) -> ExternType {
        match self {
            Self::Function(ft) => ExternType::Function(ft.ty(store)),
            Self::Memory(ft) => ExternType::Memory(ft.ty(store)),
            Self::Table(tt) => ExternType::Table(tt.ty(store)),
            Self::Global(gt) => ExternType::Global(gt.ty(store)),
            Self::Tag(tt) => ExternType::Tag(tt.ty(store)),
        }
    }

    /// Create an `Extern` from an `wasmer_engine::Export`.
    pub fn from_vm_extern(store: &mut impl AsStoreMut, vm_extern: VMExtern) -> Self {
        vm_extern.to_extern(store)
    }

    /// Checks whether this `Extern` can be used with the given context.
    pub fn is_from_store(&self, store: &impl AsStoreRef) -> bool {
        match self {
            Self::Function(f) => f.is_from_store(store),
            Self::Global(g) => g.is_from_store(store),
            Self::Tag(t) => t.is_from_store(store),
            Self::Memory(m) => m.is_from_store(store),
            Self::Table(t) => t.is_from_store(store),
        }
    }

    /// To `VMExtern`.
    pub fn to_vm_extern(&self) -> VMExtern {
        match self {
            Self::Function(f) => f.to_vm_extern(),
            Self::Global(g) => g.to_vm_extern(),
            Self::Tag(t) => t.to_vm_extern(),
            Self::Memory(m) => m.to_vm_extern(),
            Self::Table(t) => t.to_vm_extern(),
        }
    }
}

impl<'a> Exportable<'a> for Extern {
    fn get_self_from_extern(_extern: &'a Self) -> Result<&'a Self, ExportError> {
        // Since this is already an extern, we can just return it.
        Ok(_extern)
    }
}

impl std::fmt::Debug for Extern {
    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
        write!(
            f,
            "{}",
            match self {
                Self::Function(_) => "Function(...)",
                Self::Global(_) => "Global(...)",
                Self::Tag(_) => "Tag(...)",
                Self::Memory(_) => "Memory(...)",
                Self::Table(_) => "Table(...)",
            }
        )
    }
}

impl From<Function> for Extern {
    fn from(r: Function) -> Self {
        Self::Function(r)
    }
}

impl From<Global> for Extern {
    fn from(r: Global) -> Self {
        Self::Global(r)
    }
}

impl From<Tag> for Extern {
    fn from(r: Tag) -> Self {
        Self::Tag(r)
    }
}

impl From<Memory> for Extern {
    fn from(r: Memory) -> Self {
        Self::Memory(r)
    }
}

impl From<Table> for Extern {
    fn from(r: Table) -> Self {
        Self::Table(r)
    }
}