ninep_proto/
deku_bytes.rs

1use alloc::vec::Vec;
2use bytes::Bytes;
3use deku::ctx::Order;
4use deku::no_std_io::{Read, Seek, Write};
5use deku::prelude::*;
6use deku::reader::Reader;
7use deku::writer::Writer;
8
9use crate::{ByteStorage, WireBytes};
10
11/// Userspace counted payload. Other environments use [`WireBytes`] directly.
12pub type DekuBytes<B = Bytes> = WireBytes<B>;
13
14impl From<Vec<u8>> for WireBytes<Bytes> {
15    fn from(vec: Vec<u8>) -> Self {
16        Self(Bytes::from(vec))
17    }
18}
19
20impl From<WireBytes<Bytes>> for Bytes {
21    fn from(deku_bytes: WireBytes<Bytes>) -> Self {
22        deku_bytes.0
23    }
24}
25
26const READ_CHUNK_SIZE: usize = 64 * 1024;
27
28impl<'a, B> DekuReader<'a, &u32> for WireBytes<B>
29where
30    B: ByteStorage + From<Vec<u8>>,
31{
32    fn from_reader_with_ctx<R: Read + Seek>(
33        reader: &mut Reader<R>,
34        count: &u32,
35    ) -> Result<Self, DekuError> {
36        let count = *count as usize;
37        // Do not allocate an untrusted length until the input supplies it.
38        let mut buf = Vec::with_capacity(count.min(READ_CHUNK_SIZE));
39        let mut remaining = count;
40        while remaining > 0 {
41            let chunk = remaining.min(READ_CHUNK_SIZE);
42            let start = buf.len();
43            buf.resize(start + chunk, 0);
44            reader.read_bytes(chunk, &mut buf[start..], Order::Lsb0)?;
45            remaining -= chunk;
46        }
47        Ok(Self(B::from(buf)))
48    }
49}
50
51impl<B: ByteStorage> DekuWriter<&u32> for WireBytes<B> {
52    fn to_writer<W: Write + Seek>(
53        &self,
54        writer: &mut Writer<W>,
55        _count: &u32,
56    ) -> Result<(), DekuError> {
57        writer.write_bytes(self.0.as_ref())?;
58        Ok(())
59    }
60}
ninep_proto/deku_bytes.rs

ninep_proto/
deku_bytes.rs
