Use SplitWhitespace for command parsing not uom

src/command_parser.rs

@@ -1,18 +1,8 @@
 use core::fmt;
 use core::num::ParseIntError;
-use core::str::{from_utf8, Utf8Error};
-use nom::{
-    IResult,
-    branch::alt,
-    bytes::complete::{is_a, tag, take_while1},
-    character::{is_digit, complete::{char, one_of}},
-    combinator::{complete, map, opt, value},
-    sequence::preceded,
-    multi::{fold_many0, fold_many1},
-    error::ErrorKind,
-    Needed,
-};
-use num_traits::{Num, ParseFloatError};
+use core::str::{from_utf8, Utf8Error, SplitAsciiWhitespace};
+use nom::error::ErrorKind;
+use num_traits::ParseFloatError;
 use serde::{Serialize, Deserialize};
 
 
@@ -193,425 +183,76 @@ pub enum Command {
     ShowHWRev,
 }
 
-fn end(input: &[u8]) -> IResult<&[u8], ()> {
-    complete(
-        fold_many0(
-            one_of("\r\n\t "),
-            (), |(), _| ()
-        )
-    )(input)
+fn load(tokens: &mut SplitAsciiWhitespace) -> Result<Command, Error> {
+    tokens.next();
+    Err(Error::Incomplete)
 }
 
-fn whitespace(input: &[u8]) -> IResult<&[u8], ()> {
-    fold_many1(char(' '), (), |(), _| ())(input)
+fn save(_tokens: &mut SplitAsciiWhitespace) -> Result<Command, Error> {
+    Err(Error::Incomplete)
 }
 
-fn unsigned(input: &[u8]) -> IResult<&[u8], Result<u32, Error>> {
-    take_while1(is_digit)(input)
-        .map(|(input, digits)| {
-            let result =
-                from_utf8(digits)
-                .map_err(|e| e.into())
-                .and_then(|digits| u32::from_str_radix(digits, 10)
-                     .map_err(|e| e.into())
-                );
-            (input, result)
-        })
+fn ipv4(_tokens: &mut SplitAsciiWhitespace) -> Result<Command, Error> {
+    Err(Error::Incomplete)
 }
 
-fn float(input: &[u8]) -> IResult<&[u8], Result<f64, Error>> {
-    let (input, sign) = opt(is_a("-"))(input)?;
-    let negative = sign.is_some();
-    let (input, digits) = take_while1(|c| is_digit(c) || c == '.' as u8)(input)?;
-    let result =
-        from_utf8(digits)
-        .map_err(|e| e.into())
-        .and_then(|digits| f64::from_str_radix(digits, 10)
-                  .map_err(|e| e.into())
-        )
-        .map(|result: f64| if negative { -result } else { result });
-    Ok((input, result))
+fn report(_tokens: &mut SplitAsciiWhitespace) -> Result<Command, Error> {
+    Err(Error::Incomplete)
 }
 
-fn off_on(input: &[u8]) -> IResult<&[u8], bool> {
-    alt((value(false, tag("off")),
-         value(true, tag("on"))
-    ))(input)
+fn pwm(_tokens: &mut SplitAsciiWhitespace) -> Result<Command, Error> {
+    Err(Error::Incomplete)
 }
 
-fn channel(input: &[u8]) -> IResult<&[u8], usize> {
-    map(one_of("01"), |c| (c as usize) - ('0' as usize))(input)
+fn center(_tokens: &mut SplitAsciiWhitespace) -> Result<Command, Error> {
+    Err(Error::Incomplete)
 }
 
-fn report(input: &[u8]) -> IResult<&[u8], Command> {
-    preceded(
-        tag("report"),
-        alt((
-            preceded(
-                whitespace,
-                preceded(
-                    tag("mode"),
-                    alt((
-                        preceded(
-                            whitespace,
-                            // `report mode <on | off>` - Switch repoting mode
-                            map(off_on, Command::Reporting)
-                        ),
-                        // `report mode` - Show current reporting state
-                        value(Command::Show(ShowCommand::Reporting), end)
-                    ))
-                )),
-            // `report` - Report once
-            value(Command::Show(ShowCommand::Input), end)
-        ))
-    )(input)
+fn pid(_tokens: &mut SplitAsciiWhitespace) -> Result<Command, Error> {
+    Err(Error::Incomplete)
 }
 
-fn pwm_setup(input: &[u8]) -> IResult<&[u8], Result<(PwmPin, f64), Error>> {
-    let result_with_pin = |pin: PwmPin|
-        move |result: Result<f64, Error>|
-        result.map(|value| (pin, value));
-
-    alt((
-        map(
-            preceded(
-                tag("i_set"),
-                preceded(
-                    whitespace,
-                    float
-                )
-            ),
-            result_with_pin(PwmPin::ISet)
-        ),
-        map(
-            preceded(
-                tag("max_i_pos"),
-                preceded(
-                    whitespace,
-                    float
-                )
-            ),
-            result_with_pin(PwmPin::MaxIPos)
-        ),
-        map(
-            preceded(
-                tag("max_i_neg"),
-                preceded(
-                    whitespace,
-                    float
-                )
-            ),
-            result_with_pin(PwmPin::MaxINeg)
-        ),
-        map(
-            preceded(
-                tag("max_v"),
-                preceded(
-                    whitespace,
-                    float
-                )
-            ),
-            result_with_pin(PwmPin::MaxV)
-        ))
-    )(input)
+fn s_h(_tokens: &mut SplitAsciiWhitespace) -> Result<Command, Error> {
+    Err(Error::Incomplete)
 }
 
-/// `pwm <0-1> pid` - Set PWM to be controlled by PID
-fn pwm_pid(input: &[u8]) -> IResult<&[u8], ()> {
-    value((), tag("pid"))(input)
+fn postfilter(_tokens: &mut SplitAsciiWhitespace) -> Result<Command, Error> {
+    Err(Error::Incomplete)
 }
 
-fn pwm(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
-    let (input, _) = tag("pwm")(input)?;
-    alt((
-        |input| {
-            let (input, _) = whitespace(input)?;
-            let (input, channel) = channel(input)?;
-            let (input, _) = whitespace(input)?;
-            let (input, result) = alt((
-                |input| {
-                    let (input, ()) = pwm_pid(input)?;
-                    Ok((input, Ok(Command::PwmPid { channel })))
-                },
-                |input| {
-                    let (input, config) = pwm_setup(input)?;
-                    match config {
-                        Ok((pin, value)) =>
-                            Ok((input, Ok(Command::Pwm { channel, pin, value }))),
-                        Err(e) =>
-                            Ok((input, Err(e))),
-                    }
-                },
-            ))(input)?;
-            end(input)?;
-            Ok((input, result))
-        },
-        value(Ok(Command::Show(ShowCommand::Pwm)), end)
-    ))(input)
+fn fan(_tokens: &mut SplitAsciiWhitespace) -> Result<Command, Error> {
+    Err(Error::Incomplete)
 }
 
-fn center_point(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
-    let (input, _) = tag("center")(input)?;
-    let (input, _) = whitespace(input)?;
-    let (input, channel) = channel(input)?;
-    let (input, _) = whitespace(input)?;
-    let (input, center) = alt((
-        value(Ok(CenterPoint::Vref), tag("vref")),
-        |input| {
-            let (input, value) = float(input)?;
-            Ok((input, value.map(|value| CenterPoint::Override(value as f32))))
-        }
-    ))(input)?;
-    end(input)?;
-    Ok((input, center.map(|center| Command::CenterPoint {
-        channel,
-        center,
-    })))
-}
-
-/// `pid <0-1> <parameter> <value>`
-fn pid_parameter(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
-    let (input, channel) = channel(input)?;
-    let (input, _) = whitespace(input)?;
-    let (input, parameter) =
-        alt((value(PidParameter::Target, tag("target")),
-             value(PidParameter::KP, tag("kp")),
-             value(PidParameter::KI, tag("ki")),
-             value(PidParameter::KD, tag("kd")),
-             value(PidParameter::OutputMin, tag("output_min")),
-             value(PidParameter::OutputMax, tag("output_max")),
-        ))(input)?;
-    let (input, _) = whitespace(input)?;
-    let (input, value) = float(input)?;
-    let result = value
-        .map(|value| Command::Pid { channel, parameter, value });
-    Ok((input, result))
-}
-
-/// `pid` | `pid <pid_parameter>`
-fn pid(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
-    let (input, _) = tag("pid")(input)?;
-    alt((
-        preceded(
-            whitespace,
-            pid_parameter
-        ),
-        value(Ok(Command::Show(ShowCommand::Pid)), end)
-    ))(input)
-}
-
-/// `s-h <0-1> <parameter> <value>`
-fn steinhart_hart_parameter(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
-    let (input, channel) = channel(input)?;
-    let (input, _) = whitespace(input)?;
-    let (input, parameter) =
-        alt((value(ShParameter::T0, tag("t0")),
-             value(ShParameter::B, tag("b")),
-             value(ShParameter::R0, tag("r0"))
-        ))(input)?;
-    let (input, _) = whitespace(input)?;
-    let (input, value) = float(input)?;
-    let result = value
-        .map(|value| Command::SteinhartHart { channel, parameter, value });
-    Ok((input, result))
-}
-
-/// `s-h` | `s-h <steinhart_hart_parameter>`
-fn steinhart_hart(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
-    let (input, _) = tag("s-h")(input)?;
-    alt((
-        preceded(
-            whitespace,
-            steinhart_hart_parameter
-        ),
-        value(Ok(Command::Show(ShowCommand::SteinhartHart)), end)
-    ))(input)
-}
-
-fn postfilter(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
-    let (input, _) = tag("postfilter")(input)?;
-    alt((
-        preceded(
-            whitespace,
-            |input| {
-                let (input, channel) = channel(input)?;
-                let (input, _) = whitespace(input)?;
-                alt((
-                    value(Ok(Command::PostFilter {
-                        channel,
-                        rate: None,
-                    }), tag("off")),
-                    move |input| {
-                        let (input, _) = tag("rate")(input)?;
-                        let (input, _) = whitespace(input)?;
-                        let (input, rate) = float(input)?;
-                        let result = rate
-                            .map(|rate| Command::PostFilter {
-                                channel,
-                                rate: Some(rate as f32),
-                            });
-                        Ok((input, result))
-                    }
-                ))(input)
-            }
-        ),
-        value(Ok(Command::Show(ShowCommand::PostFilter)), end)
-    ))(input)
-}
-
-fn load(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
-    let (input, _) = tag("load")(input)?;
-    let (input, channel) = alt((
-        |input| {
-            let (input, _) = whitespace(input)?;
-            let (input, channel) = channel(input)?;
-            let (input, _) = end(input)?;
-            Ok((input, Some(channel)))
-        },
-        value(None, end)
-    ))(input)?;
-
-    let result = Ok(Command::Load { channel });
-    Ok((input, result))
-}
-
-fn save(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
-    let (input, _) = tag("save")(input)?;
-    let (input, channel) = alt((
-        |input| {
-            let (input, _) = whitespace(input)?;
-            let (input, channel) = channel(input)?;
-            let (input, _) = end(input)?;
-            Ok((input, Some(channel)))
-        },
-        value(None, end)
-    ))(input)?;
-
-    let result = Ok(Command::Save { channel });
-    Ok((input, result))
-}
-
-fn ipv4_addr(input: &[u8]) -> IResult<&[u8], Result<[u8; 4], Error>> {
-    let (input, a) = unsigned(input)?;
-    let (input, _) = tag(".")(input)?;
-    let (input, b) = unsigned(input)?;
-    let (input, _) = tag(".")(input)?;
-    let (input, c) = unsigned(input)?;
-    let (input, _) = tag(".")(input)?;
-    let (input, d) = unsigned(input)?;
-    let address = move || Ok([a? as u8, b? as u8, c? as u8, d? as u8]);
-    Ok((input, address()))
-}
-
-fn ipv4(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
-    let (input, _) = tag("ipv4")(input)?;
-    alt((
-        |input| {
-            let (input, _) = whitespace(input)?;
-            let (input, address) = ipv4_addr(input)?;
-            let (input, _) = tag("/")(input)?;
-            let (input, mask_len) = unsigned(input)?;
-            let (input, gateway) = alt((
-                |input| {
-                    let (input, _) = whitespace(input)?;
-                    let (input, gateway) = ipv4_addr(input)?;
-                    Ok((input, gateway.map(Some)))
-                },
-                value(Ok(None), end),
-            ))(input)?;
-
-            let result = move || {
-                Ok(Command::Ipv4(Ipv4Config {
-                    address: address?,
-                    mask_len: mask_len? as u8,
-                    gateway: gateway?,
-                }))
-            };
-            Ok((input, result()))
-        },
-        value(Ok(Command::Show(ShowCommand::Ipv4)), end),
-    ))(input)
-}
-
-fn fan(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
-    let (input, _) = tag("fan")(input)?;
-    alt((
-        |input| {
-            let (input, _) = whitespace(input)?;
-
-            let (input, result) = alt((
-                |input| {
-                    let (input, _) = tag("auto")(input)?;
-                    Ok((input, Ok(Command::FanAuto)))
-                },
-                |input| {
-                    let (input, value) = unsigned(input)?;
-                    Ok((input, Ok(Command::FanSet { fan_pwm: value.unwrap_or(0)})))
-                },
-            ))(input)?;
-            Ok((input, result))
-        },
-        value(Ok(Command::ShowFan), end)
-    ))(input)
-}
-
-fn fan_curve(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
-    let (input, _) = tag("fcurve")(input)?;
-    alt((
-        |input| {
-            let (input, _) = whitespace(input)?;
-            let (input, result) = alt((
-                |input| {
-                    let (input, _) = tag("default")(input)?;
-                    Ok((input, Ok(Command::FanCurveDefaults)))
-                },
-                |input| {
-                    let (input, k_a) = float(input)?;
-                    let (input, _) = whitespace(input)?;
-                    let (input, k_b) = float(input)?;
-                    let (input, _) = whitespace(input)?;
-                    let (input, k_c) = float(input)?;
-                    if k_a.is_ok() && k_b.is_ok() && k_c.is_ok() {
-                        Ok((input, Ok(Command::FanCurve { k_a: k_a.unwrap() as f32, k_b: k_b.unwrap() as f32, k_c: k_c.unwrap() as f32 })))
-                    } else {
-                        Err(nom::Err::Incomplete(Needed::Size(3)))
-                    }
-                },
-            ))(input)?;
-            Ok((input, result))
-        },
-        value(Err(Error::Incomplete), end)
-    ))(input)
-}
-
-fn command(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
-    alt((value(Ok(Command::Quit), tag("quit")),
-         load,
-         save,
-         value(Ok(Command::Reset), tag("reset")),
-         ipv4,
-         map(report, Ok),
-         pwm,
-         center_point,
-         pid,
-         steinhart_hart,
-         postfilter,
-         value(Ok(Command::Dfu), tag("dfu")),
-         fan,
-         fan_curve,
-         value(Ok(Command::ShowHWRev), tag("hwrev")),
-    ))(input)
+fn fcurve(_tokens: &mut SplitAsciiWhitespace) -> Result<Command, Error> {
+    Err(Error::Incomplete)
 }
 
 impl Command {
     pub fn parse(input: &[u8]) -> Result<Self, Error> {
-        match command(input) {
-            Ok((input_remain, result)) if input_remain.len() == 0 =>
-                result,
-            Ok((input_remain, _)) =>
-                Err(Error::UnexpectedInput(input_remain[0])),
-            Err(e) =>
-                Err(e.into()),
+        let mut tokens = from_utf8(input).unwrap().split_ascii_whitespace();
+        match tokens.next() {
+            Some(keyword) => {
+                match keyword {
+                    "quit" => Ok(Command::Quit),
+                    "load" => load(&mut tokens),
+                    "save" => save(&mut tokens),
+                    "reset" => Ok(Command::Reset),
+                    "ipv4" => ipv4(&mut tokens),
+                    "report" => report(&mut tokens),
+                    "pwm" => pwm(&mut tokens),
+                    "center" => center(&mut tokens),
+                    "pid" => pid(&mut tokens),
+                    "s-h" => s_h(&mut tokens),
+                    "postfilter" => postfilter(&mut tokens),
+                    "dfu" => Ok(Command::Dfu),
+                    "fan" => fan(&mut tokens),
+                    "fcurve" => fcurve(&mut tokens),
+                    "hwrev" => Ok(Command::ShowHWRev),
+                    _ => Err(Error::Incomplete),
+                }
+            }
+            None => Err(Error::Incomplete),
         }
     }
 }