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
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
// Copyright (c) The Diem Core Contributors
// Copyright (c) The Move Contributors
// SPDX-License-Identifier: Apache-2.0

use crate::{
    interpreter::Interpreter, loader::Resolver, native_extensions::NativeContextExtensions,
};
use move_binary_format::errors::{PartialVMError, PartialVMResult};
use move_core_types::{
    account_address::AccountAddress,
    gas_schedule::CostTable,
    identifier::Identifier,
    language_storage::TypeTag,
    value::MoveTypeLayout,
    vm_status::{StatusCode, StatusType},
};
use move_vm_types::{
    data_store::DataStore, gas_schedule::GasStatus, loaded_data::runtime_types::Type,
    natives::function::NativeResult, values::Value,
};
use std::{
    collections::{HashMap, VecDeque},
    fmt::Write,
};

pub type NativeFunction =
    fn(&mut NativeContext, Vec<Type>, VecDeque<Value>) -> PartialVMResult<NativeResult>;

pub type NativeFunctionTable = Vec<(AccountAddress, Identifier, Identifier, NativeFunction)>;

pub fn make_table(
    addr: AccountAddress,
    elems: &[(&str, &str, NativeFunction)],
) -> NativeFunctionTable {
    make_table_from_iter(addr, elems.iter().cloned())
}

pub fn make_table_from_iter<S: Into<Box<str>>>(
    addr: AccountAddress,
    elems: impl IntoIterator<Item = (S, S, NativeFunction)>,
) -> NativeFunctionTable {
    elems
        .into_iter()
        .map(|(module_name, func_name, func)| {
            (
                addr,
                Identifier::new(module_name).unwrap(),
                Identifier::new(func_name).unwrap(),
                func,
            )
        })
        .collect()
}

pub(crate) struct NativeFunctions(
    HashMap<AccountAddress, HashMap<String, HashMap<String, NativeFunction>>>,
);

impl NativeFunctions {
    pub fn resolve(
        &self,
        addr: &AccountAddress,
        module_name: &str,
        func_name: &str,
    ) -> Option<NativeFunction> {
        self.0.get(addr)?.get(module_name)?.get(func_name).cloned()
    }

    pub fn new<I>(natives: I) -> PartialVMResult<Self>
    where
        I: IntoIterator<Item = (AccountAddress, Identifier, Identifier, NativeFunction)>,
    {
        let mut map = HashMap::new();
        for (addr, module_name, func_name, func) in natives.into_iter() {
            let modules = map.entry(addr).or_insert_with(HashMap::new);
            let funcs = modules
                .entry(module_name.into_string())
                .or_insert_with(HashMap::new);

            if funcs.insert(func_name.into_string(), func).is_some() {
                return Err(PartialVMError::new(StatusCode::DUPLICATE_NATIVE_FUNCTION));
            }
        }
        Ok(Self(map))
    }
}

pub struct NativeContext<'a, 'b> {
    interpreter: &'a mut Interpreter,
    data_store: &'a mut dyn DataStore,
    gas_status: &'a GasStatus<'a>,
    resolver: &'a Resolver<'a>,
    extensions: &'a mut NativeContextExtensions<'b>,
}

impl<'a, 'b> NativeContext<'a, 'b> {
    pub(crate) fn new(
        interpreter: &'a mut Interpreter,
        data_store: &'a mut dyn DataStore,
        gas_status: &'a mut GasStatus,
        resolver: &'a Resolver<'a>,
        extensions: &'a mut NativeContextExtensions<'b>,
    ) -> Self {
        Self {
            interpreter,
            data_store,
            gas_status,
            resolver,
            extensions,
        }
    }
}

impl<'a, 'b> NativeContext<'a, 'b> {
    pub fn print_stack_trace<B: Write>(&self, buf: &mut B) -> PartialVMResult<()> {
        self.interpreter
            .debug_print_stack_trace(buf, self.resolver.loader())
    }

    pub fn cost_table(&self) -> &CostTable {
        self.gas_status.cost_table()
    }

    pub fn save_event(
        &mut self,
        guid: Vec<u8>,
        seq_num: u64,
        ty: Type,
        val: Value,
    ) -> PartialVMResult<bool> {
        match self.data_store.emit_event(guid, seq_num, ty, val) {
            Ok(()) => Ok(true),
            Err(e) if e.major_status().status_type() == StatusType::InvariantViolation => Err(e),
            Err(_) => Ok(false),
        }
    }

    pub fn events(&self) -> &Vec<(Vec<u8>, u64, Type, MoveTypeLayout, Value)> {
        self.data_store.events()
    }

    pub fn type_to_type_tag(&self, ty: &Type) -> PartialVMResult<TypeTag> {
        self.resolver.loader().type_to_type_tag(ty)
    }

    pub fn type_to_type_layout(&self, ty: &Type) -> PartialVMResult<Option<MoveTypeLayout>> {
        match self.resolver.type_to_type_layout(ty) {
            Ok(ty_layout) => Ok(Some(ty_layout)),
            Err(e) if e.major_status().status_type() == StatusType::InvariantViolation => Err(e),
            Err(_) => Ok(None),
        }
    }

    pub fn extensions(&self) -> &NativeContextExtensions<'b> {
        self.extensions
    }

    pub fn extensions_mut(&mut self) -> &mut NativeContextExtensions<'b> {
        self.extensions
    }
}