obd2/src/obd2_device.rs
Robert Sammelson 1171380877
Fix lint issues and add comments
Lint issues:
- spelling problems
- iter instead of into_iter
2025-03-20 02:17:56 -04:00

60 lines
2.7 KiB
Rust

use crate::{Error, Result};
/// A higher-level API for using an OBD-II device
pub trait Obd2Device {
/// Send an OBD-II command with mode and PID and get responses
///
/// The responses are a list with one element for each ECU that responds. The data is decoded
/// into the ODB-II bytes from the vehicle and the first two bytes of the
/// response---representing the mode and PID the vehicle received---are validated and removed.
fn obd_command(&mut self, mode: u8, pid: u8) -> Result<Vec<Vec<u8>>>;
/// Send an OBD-II command with only mode and get responses
///
/// The responses are a list with one element for each ECU that responds. The data is decoded
/// into the ODB-II bytes from the vehicle and the first byte of the response---representing
/// the mode the vehicle received---is validated and removed.
fn obd_mode_command(&mut self, mode: u8) -> Result<Vec<Vec<u8>>>;
/// Send command and get list of OBD-II responses as an array
///
/// Like [obd_command](Self::obd_command), but each ECU's response (after removing the first
/// two bytes) is converted to an array of the specified length. If any response is the wrong
/// length, and error is returned.
///
/// This function can be used when the response length is known, so that it is easier to index
/// into the response without causing a panic and without dealing with Options.
fn obd_command_len<const RESPONSE_LENGTH: usize>(
&mut self,
mode: u8,
pid: u8,
) -> Result<Vec<[u8; RESPONSE_LENGTH]>> {
self.obd_command(mode, pid)?
.into_iter()
.map(|v| {
let l = v.len();
v.try_into()
.map_err(|_| Error::IncorrectResponseLength("length", RESPONSE_LENGTH, l))
})
.collect()
}
/// Send command and get array of OBD-II responses with each as an array
///
/// Like [obd_command_len](Self::obd_command_len), but also convert the list of ECU responses
/// to an array. This can be used when the number of ECUs that should respond is known in
/// advance. Most commonly, this will be when the count of ECUs is one, for values where only a
/// single ECU should respond like the speed of the vehicle.
fn obd_command_cnt_len<const RESPONSE_COUNT: usize, const RESPONSE_LENGTH: usize>(
&mut self,
mode: u8,
pid: u8,
) -> Result<[[u8; RESPONSE_LENGTH]; RESPONSE_COUNT]> {
let result = self.obd_command_len::<RESPONSE_LENGTH>(mode, pid)?;
let count = result.len();
result
.try_into()
.map_err(|_| Error::IncorrectResponseLength("count", RESPONSE_COUNT, count))
}
}