norfs/medium/
ram.rs

1use crate::{medium::StorageMedium, StorageError};
2
3use super::WriteGranularity;
4
5pub struct RamStorage<const STORAGE_SIZE: usize, const BLOCK_SIZE: usize, const GRANULARITY: usize>
6{
7    pub(crate) data: [u8; STORAGE_SIZE],
8}
9
10impl<const STORAGE_SIZE: usize, const BLOCK_SIZE: usize, const GRANULARITY: usize> Default
11    for RamStorage<STORAGE_SIZE, BLOCK_SIZE, GRANULARITY>
12{
13    fn default() -> Self {
14        Self::new()
15    }
16}
17
18impl<const STORAGE_SIZE: usize, const BLOCK_SIZE: usize, const GRANULARITY: usize>
19    RamStorage<STORAGE_SIZE, BLOCK_SIZE, GRANULARITY>
20{
21    pub const fn new() -> Self {
22        Self {
23            data: [0xFF; STORAGE_SIZE],
24        }
25    }
26
27    fn offset(block: usize, offset: usize) -> usize {
28        block * Self::BLOCK_SIZE + offset
29    }
30
31    #[cfg(test)]
32    pub fn debug_print(&self) {
33        for blk in 0..Self::BLOCK_COUNT {
34            print!("{blk:02X}:");
35
36            for byte in 0..Self::BLOCK_SIZE {
37                print!(" {:02X}", self.data[Self::offset(blk, byte)]);
38            }
39
40            println!();
41        }
42    }
43}
44
45impl<const STORAGE_SIZE: usize, const BLOCK_SIZE: usize, const GRANULARITY: usize> StorageMedium
46    for RamStorage<STORAGE_SIZE, BLOCK_SIZE, GRANULARITY>
47{
48    const BLOCK_SIZE: usize = BLOCK_SIZE;
49    const BLOCK_COUNT: usize = STORAGE_SIZE / BLOCK_SIZE;
50    const WRITE_GRANULARITY: WriteGranularity = WriteGranularity::Word(GRANULARITY);
51
52    async fn erase(&mut self, block: usize) -> Result<(), StorageError> {
53        let offset = Self::offset(block, 0);
54
55        self.data[offset..offset + Self::BLOCK_SIZE].fill(0xFF);
56
57        Ok(())
58    }
59
60    async fn read(
61        &mut self,
62        block: usize,
63        offset: usize,
64        data: &mut [u8],
65    ) -> Result<(), StorageError> {
66        assert!(
67            offset + data.len() <= Self::BLOCK_SIZE,
68            "{offset} + {} <= {}",
69            data.len(),
70            Self::BLOCK_SIZE
71        );
72        let offset = Self::offset(block, offset);
73
74        data.copy_from_slice(&self.data[offset..offset + data.len()]);
75
76        Ok(())
77    }
78
79    async fn write(
80        &mut self,
81        block: usize,
82        offset: usize,
83        data: &[u8],
84    ) -> Result<(), StorageError> {
85        assert!(
86            offset + data.len() <= Self::BLOCK_SIZE,
87            "{offset} + {} <= {}",
88            data.len(),
89            Self::BLOCK_SIZE
90        );
91        let offset = Self::offset(block, offset);
92
93        for (src, dst) in data.iter().zip(self.data[offset..].iter_mut()) {
94            assert_eq!(*dst, 0xFF);
95            *dst = *src;
96        }
97
98        Ok(())
99    }
100}
norfs/medium/ram.rs

norfs/medium/
ram.rs
