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use super::prelude::*;
#[derive(Debug)]
pub struct m<'a> {
pub addr: &'a [u8],
pub len: usize,
pub buf: &'a mut [u8],
}
impl<'a> ParseCommand<'a> for m<'a> {
#[inline(always)]
fn from_packet(buf: PacketBuf<'a>) -> Option<Self> {
// the total packet buffer currently looks like:
//
// +------+--------------------+-------------------+-------+-----------------+
// | "$m" | addr (hex-encoded) | len (hex-encoded) | "#XX" | empty space ... |
// +------+--------------------+-------------------+-------+-----------------+
//
// Unfortunately, while `len` can be hex-decoded right here and now into a
// `usize`, `addr` corresponds to a Target::Arch::Usize, which requires holding
// on to a valid &[u8] reference into the buffer.
//
// While it's not _perfectly_ efficient, simply leaving the decoded addr in
// place and wasting a couple bytes is probably the easiest way to tackle this
// problem:
//
// +------+------------------+------------------------------------------------+
// | "$m" | addr (raw bytes) | usable buffer ... |
// +------+------------------+------------------------------------------------+
let (buf, body_range) = buf.into_raw_buf();
let body = buf.get_mut(body_range.start..body_range.end)?;
let mut body = body.split_mut(|b| *b == b',');
let addr = decode_hex_buf(body.next()?).ok()?;
let addr_len = addr.len();
let len = decode_hex(body.next()?).ok()?;
// ensures that `split_at_mut` doesn't panic
if buf.len() < body_range.start + addr_len {
return None;
}
let (addr, buf) = buf.split_at_mut(body_range.start + addr_len);
let addr = addr.get(b"$m".len()..)?;
Some(m { addr, len, buf })
}
}