it_memory_traits/
lib.rs

1/*
2 * Copyright 2022 Fluence Labs Limited
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *     http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17mod errors;
18
19pub use errors::MemoryAccessError;
20
21pub trait Store: Send {
22    type ActualStore<'c>: Send;
23}
24
25pub trait MemoryReadable<Store: self::Store> {
26    /// This function will panic if the `offset` is out of bounds.
27    /// It is caller's responsibility to check if the offset is in bounds
28    /// using `MemoryView::check_bounds` function
29    fn read_byte(&self, store: &mut <Store as self::Store>::ActualStore<'_>, offset: u32) -> u8;
30
31    /// This function will panic if `[offset..offset + COUNT]` is out of bounds.
32    /// It is caller's responsibility to check if the offset is in bounds
33    /// using `MemoryView::check_bounds` function.
34    fn read_array<const COUNT: usize>(
35        &self,
36        store: &mut <Store as self::Store>::ActualStore<'_>,
37        offset: u32,
38    ) -> [u8; COUNT];
39
40    /// This function will panic if `[offset..offset + size]` is out of bounds.
41    /// It is caller's responsibility to check if the offset is in bounds
42    /// using `MemoryView::check_bounds` function.
43    fn read_vec(
44        &self,
45        store: &mut <Store as self::Store>::ActualStore<'_>,
46        offset: u32,
47        size: u32,
48    ) -> Vec<u8>;
49}
50
51pub trait MemoryWritable<Store: self::Store> {
52    /// This function will panic if `offset` is out of bounds.
53    /// It is caller's responsibility to check if the offset is in bounds
54    /// using `MemoryView::check_bounds` function.
55    fn write_byte(
56        &self,
57        store: &mut <Store as self::Store>::ActualStore<'_>,
58        offset: u32,
59        value: u8,
60    );
61
62    /// This function will panic if `[offset..offset + bytes.len()]`.is out of bounds.
63    /// It is caller's responsibility to check if the offset is in bounds
64    /// using `MemoryView::check_bounds` function.
65    fn write_bytes(
66        &self,
67        store: &mut <Store as self::Store>::ActualStore<'_>,
68        offset: u32,
69        bytes: &[u8],
70    );
71}
72
73pub trait MemoryView<Store: self::Store>:
74    Send + MemoryWritable<Store> + MemoryReadable<Store>
75{
76    /// For optimization purposes, user must check bounds first, then try read-write to memory
77    /// `MemoryWritable` and `MemoryReadable` functions will panic in case of out of bounds access`
78    fn check_bounds(
79        &self,
80        store: &mut <Store as self::Store>::ActualStore<'_>,
81        offset: u32,
82        size: u32,
83    ) -> Result<(), MemoryAccessError>;
84}
85
86pub trait Memory<View, Store: self::Store>: Send
87where
88    View: MemoryView<Store>,
89{
90    fn view(&self) -> View;
91}
it_memory_traits/lib.rs

it_memory_traits/
lib.rs
