netapp/src/proto2.rs
2022-02-21 12:04:09 +01:00

75 lines
1.7 KiB
Rust

use crate::error::*;
use crate::proto::*;
pub(crate) struct QueryMessage<'a> {
pub(crate) prio: RequestPriority,
pub(crate) path: &'a [u8],
pub(crate) telemetry_id: Option<Vec<u8>>,
pub(crate) body: &'a [u8],
}
/// QueryMessage encoding:
/// - priority: u8
/// - path length: u8
/// - path: [u8; path length]
/// - telemetry id length: u8
/// - telemetry id: [u8; telemetry id length]
/// - body [u8; ..]
impl<'a> QueryMessage<'a> {
pub(crate) fn encode(self) -> Vec<u8> {
let tel_len = match &self.telemetry_id {
Some(t) => t.len(),
None => 0,
};
let mut ret = Vec::with_capacity(10 + self.path.len() + tel_len + self.body.len());
ret.push(self.prio);
ret.push(self.path.len() as u8);
ret.extend_from_slice(self.path);
if let Some(t) = self.telemetry_id {
ret.push(t.len() as u8);
ret.extend(t);
} else {
ret.push(0u8);
}
ret.extend_from_slice(self.body);
ret
}
pub(crate) fn decode(bytes: &'a [u8]) -> Result<Self, Error> {
if bytes.len() < 3 {
return Err(Error::Message("Invalid protocol message".into()));
}
let path_length = bytes[1] as usize;
if bytes.len() < 3 + path_length {
return Err(Error::Message("Invalid protocol message".into()));
}
let telemetry_id_len = bytes[2 + path_length] as usize;
if bytes.len() < 3 + path_length + telemetry_id_len {
return Err(Error::Message("Invalid protocol message".into()));
}
let path = &bytes[2..2 + path_length];
let telemetry_id = if telemetry_id_len > 0 {
Some(bytes[3 + path_length..3 + path_length + telemetry_id_len].to_vec())
} else {
None
};
let body = &bytes[3 + path_length + telemetry_id_len..];
Ok(Self {
prio: bytes[0],
path,
telemetry_id,
body,
})
}
}