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
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144

use crate::indexes::{FunctionIndex, GlobalIndex, MemoryIndex, TableIndex};
use crate::lib::std::boxed::Box;

use enumset::__internal::EnumSetTypeRepr;
use rkyv::{Archive, CheckBytes, Deserialize as RkyvDeserialize, Serialize as RkyvSerialize};
#[cfg(feature = "enable-serde")]
use serde::{Deserialize, Serialize};

/// A WebAssembly table initializer.
#[derive(Clone, Debug, Hash, PartialEq, Eq, RkyvSerialize, RkyvDeserialize, Archive)]
#[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
#[archive_attr(derive(CheckBytes))]
pub struct TableInitializer {
    /// The index of a table to initialize.
    pub table_index: TableIndex,
    /// Optionally, a global variable giving a base index.
    pub base: Option<GlobalIndex>,
    /// The offset to add to the base.
    pub offset: usize,
    /// The values to write into the table elements.
    pub elements: Box<[FunctionIndex]>,
}

/// A memory index and offset within that memory where a data initialization
/// should be performed.
#[derive(Clone, Debug, PartialEq, Eq, RkyvSerialize, RkyvDeserialize, Archive)]
#[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
#[archive_attr(derive(CheckBytes))]
pub struct DataInitializerLocation {
    /// The index of the memory to initialize.
    pub memory_index: MemoryIndex,

    /// Optionally a Global variable base to initialize at.
    pub base: Option<GlobalIndex>,

    /// A constant offset to initialize at.
    pub offset: usize,
}

/// Any struct that acts like a `DataInitializerLocation`.
#[allow(missing_docs)]
pub trait DataInitializerLocationLike {
    fn memory_index(&self) -> MemoryIndex;
    fn base(&self) -> Option<GlobalIndex>;
    fn offset(&self) -> usize;
}

impl DataInitializerLocationLike for &DataInitializerLocation {
    fn memory_index(&self) -> MemoryIndex {
        self.memory_index
    }

    fn base(&self) -> Option<GlobalIndex> {
        self.base
    }

    fn offset(&self) -> usize {
        self.offset
    }
}

impl DataInitializerLocationLike for &ArchivedDataInitializerLocation {
    fn memory_index(&self) -> MemoryIndex {
        MemoryIndex::from_u32(self.memory_index.as_u32())
    }

    fn base(&self) -> Option<GlobalIndex> {
        match self.base {
            rkyv::option::ArchivedOption::None => None,
            rkyv::option::ArchivedOption::Some(base) => Some(GlobalIndex::from_u32(base.as_u32())),
        }
    }

    fn offset(&self) -> usize {
        self.offset.to_usize()
    }
}

/// A data initializer for linear memory.
#[derive(Debug)]
#[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
pub struct DataInitializer<'data> {
    /// The location where the initialization is to be performed.
    pub location: DataInitializerLocation,

    /// The initialization data.
    pub data: &'data [u8],
}

/// As `DataInitializer` but owning the data rather than
/// holding a reference to it
#[derive(Debug, Clone, PartialEq, Eq, RkyvSerialize, RkyvDeserialize, Archive)]
#[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
#[archive_attr(derive(CheckBytes))]
pub struct OwnedDataInitializer {
    /// The location where the initialization is to be performed.
    pub location: DataInitializerLocation,

    /// The initialization owned data.
    pub data: Box<[u8]>,
}

/// Any struct that acts like a `DataInitializer`.
#[allow(missing_docs)]
pub trait DataInitializerLike<'a> {
    type Location: DataInitializerLocationLike + Copy + 'a;

    fn location(&self) -> Self::Location;
    fn data(&self) -> &'a [u8];
}

impl OwnedDataInitializer {
    /// Creates a new `OwnedDataInitializer` from a `DataInitializer`.
    pub fn new(borrowed: &DataInitializer<'_>) -> Self {
        Self {
            location: borrowed.location.clone(),
            data: borrowed.data.to_vec().into_boxed_slice(),
        }
    }
}

impl<'a> DataInitializerLike<'a> for &'a OwnedDataInitializer {
    type Location = &'a DataInitializerLocation;

    fn location(&self) -> Self::Location {
        &self.location
    }

    fn data(&self) -> &'a [u8] {
        self.data.as_ref()
    }
}

impl<'a> DataInitializerLike<'a> for &'a ArchivedOwnedDataInitializer {
    type Location = &'a ArchivedDataInitializerLocation;

    fn location(&self) -> Self::Location {
        &self.location
    }

    fn data(&self) -> &'a [u8] {
        self.data.as_ref()
    }
}