extern crate nom; extern crate exec_helpers; use std::collections::HashMap; use std::io::{Write, Read}; use std::fmt::{Display, Debug}; #[derive(Debug, PartialEq, Eq, Clone)] pub enum T { // Unit Unit, // Boolean N1(bool), // Naturals N3(u8), N6(u64), N7(u128), // Integers I3(i8), I6(i64), I7(i128), // Text // TODO: make into &str Text(String), // TODO: rename to Bytes Binary(Vec<u8>), // Tags // TODO: make into &str Sum(Tag<String, T>), // TODO: make into &str Record(HashMap<String, T>), List(Vec<T>), } impl T { pub fn to_u<'a>(&'a self) -> U<'a> { match self { T::Unit => U::Unit, T::N1(b) => U::N1(*b), T::N3(u) => U::N3(*u), T::N6(u) => U::N6(*u), T::N7(u) => U::N7(*u), T::I3(i) => U::I3(*i), T::I6(i) => U::I6(*i), T::I7(i) => U::I7(*i), T::Text(t) => U::Text(t.as_str()), T::Binary(v) => U::Binary(v), T::Sum(Tag { tag, val }) => U::Sum( Tag { tag: tag.as_str(), val: Box::new(val.to_u()) } ), T::Record(map) => U::Record( map.iter().map(|(k, v)| (k.as_str(), v.to_u())).collect() ), T::List(l) => U::List( l.iter().map(|v| v.to_u()).collect::<Vec<U<'a>>>() ), } } pub fn encode<'a>(&'a self) -> Vec<u8> { match self { // TODO: don’t go via U, inefficient o => o.to_u().encode() } } } #[derive(Debug, PartialEq, Eq, Clone)] pub enum U<'a> { Unit, // Boolean N1(bool), // Naturals N3(u8), N6(u64), N7(u128), // Integers I3(i8), I6(i64), I7(i128), // Text Text(&'a str), Binary(&'a [u8]), // Tags // TODO: the U-recursion we do here means we can’t be breadth-lazy anymore // like we originally planned; maybe we want to go `U<'a>` → `&'a [u8]` again? Sum(Tag<&'a str, U<'a>>), Record(HashMap<&'a str, U<'a>>), List(Vec<U<'a>>), } impl<'a> U<'a> { pub fn encode(&self) -> Vec<u8> { let mut c = std::io::Cursor::new(vec![]); encode(&mut c, self); c.into_inner() } pub fn to_t(&self) -> T { match self { U::Unit => T::Unit, U::N1(b) => T::N1(*b), U::N3(u) => T::N3(*u), U::N6(u) => T::N6(*u), U::N7(u) => T::N7(*u), U::I3(i) => T::I3(*i), U::I6(i) => T::I6(*i), U::I7(i) => T::I7(*i), U::Text(t) => T::Text((*t).to_owned()), U::Binary(v) => T::Binary((*v).to_owned()), U::Sum(Tag { tag, val }) => T::Sum( Tag { tag: (*tag).to_owned(), val: Box::new(val.to_t()) } ), U::Record(map) => T::Record( map.iter().map(|(k, v)| ((*k).to_owned(), v.to_t())).collect::<HashMap<String, T>>() ), U::List(l) => T::List( l.iter().map(|v| v.to_t()).collect::<Vec<T>>() ), } } } #[derive(Debug, PartialEq, Eq, Clone)] pub struct Tag<S, A> { // TODO: make into &str pub tag: S, pub val: Box<A> } impl<S, A> Tag<S, A> { fn map<F, B>(self, f: F) -> Tag<S, B> where F: Fn(A) -> B { Tag { tag: self.tag, val: Box::new(f(*self.val)) } } } fn encode_tag<W: Write>(w: &mut W, tag: &str, val: &U) -> std::io::Result<()> { write!(w, "<{}:{}|", tag.len(), tag)?; encode(w, val)?; Ok(()) } pub fn encode<W: Write>(w: &mut W, u: &U) -> std::io::Result<()> { match u { U::Unit => write!(w, "u,"), U::N1(b) => if *b { write!(w, "n1:1,") } else { write!(w, "n1:0,") }, U::N3(n) => write!(w, "n3:{},", n), U::N6(n) => write!(w, "n6:{},", n), U::N7(n) => write!(w, "n7:{},", n), U::I3(i) => write!(w, "i3:{},", i), U::I6(i) => write!(w, "i6:{},", i), U::I7(i) => write!(w, "i7:{},", i), U::Text(s) => { write!(w, "t{}:", s.len()); w.write(s.as_bytes()); write!(w, ",") } U::Binary(s) => { write!(w, "b{}:", s.len()); w.write(&s); write!(w, ",") }, U::Sum(Tag{tag, val}) => encode_tag(w, tag, val), U::Record(m) => { let mut c = std::io::Cursor::new(vec![]); for (k, v) in m { encode_tag(&mut c, k, v)?; } write!(w, "{{{}:", c.get_ref().len())?; w.write(c.get_ref())?; write!(w, "}}") }, U::List(l) => { let mut c = std::io::Cursor::new(vec![]); for u in l { encode(&mut c, u)?; } write!(w, "[{}:", c.get_ref().len())?; w.write(c.get_ref())?; write!(w, "]") } } } pub fn text(s: String) -> T { T::Text(s) } pub fn u_from_stdin_or_die_user_error<'a>(prog_name: &'_ str, stdin_buf: &'a mut Vec<u8>) -> U<'a> { std::io::stdin().lock().read_to_end(stdin_buf); let u = match parse::u_u(stdin_buf) { Ok((rest, u)) => match rest { b"" => u, _ => exec_helpers::die_user_error(prog_name, format!("stdin contained some soup after netencode value: {:?}", rest)) }, Err(err) => exec_helpers::die_user_error(prog_name, format!("unable to parse netencode from stdin: {:?}", err)) }; u } pub mod parse { use super::{T, Tag, U}; use std::str::FromStr; use std::ops::Neg; use std::collections::HashMap; use nom::{IResult}; use nom::bytes::complete::{tag, take}; use nom::branch::{alt}; use nom::character::complete::{digit1, char}; use nom::sequence::{tuple}; use nom::combinator::{map, map_res, flat_map, map_parser, opt}; use nom::error::{context, ErrorKind, ParseError}; fn unit_t(s: &[u8]) -> IResult<&[u8], ()> { let (s, _) = context("unit", tag("u,"))(s)?; Ok((s, ())) } fn usize_t(s: &[u8]) -> IResult<&[u8], usize> { context( "usize", map_res( map_res(digit1, |n| std::str::from_utf8(n)), |s| s.parse::<usize>()) )(s) } fn sized(begin: char, end: char) -> impl Fn(&[u8]) -> IResult<&[u8], &[u8]> { move |s: &[u8]| { let (s, (_, len, _)) = tuple(( char(begin), usize_t, char(':') ))(s)?; let (s, (res, _)) = tuple(( take(len), char(end) ))(s)?; Ok((s, res)) } } fn uint_t<'a, I: FromStr + 'a>(t: &'static str) -> impl Fn(&'a [u8]) -> IResult<&'a [u8], I> { move |s: &'a [u8]| { let (s, (_, _, int, _)) = tuple(( tag(t.as_bytes()), char(':'), map_res( map_res(digit1, |n: &[u8]| std::str::from_utf8(n)), |s| s.parse::<I>() ), char(',') ))(s)?; Ok((s, int)) } } fn bool_t<'a>() -> impl Fn(&'a [u8]) -> IResult<&'a [u8], bool> { context("bool", alt(( map(tag("n1:0,"), |_| false), map(tag("n1:1,"), |_| true), ))) } fn int_t<'a, I: FromStr + Neg<Output=I>>(t: &'static str) -> impl Fn(&'a [u8]) -> IResult<&[u8], I> { context( t, move |s: &'a [u8]| { let (s, (_, _, neg, int, _)) = tuple(( tag(t.as_bytes()), char(':'), opt(char('-')), map_res( map_res(digit1, |n: &[u8]| std::str::from_utf8(n)), |s| s.parse::<I>() ), char(',') ))(s)?; let res = match neg { Some(_) => -int, None => int, }; Ok((s, res)) } ) } fn tag_t(s: &[u8]) -> IResult<&[u8], Tag<String, T>> { // recurses into the main parser map(tag_g(t_t), |Tag {tag, val}| Tag { tag: tag.to_string(), val })(s) } fn tag_g<'a, P, O>(inner: P) -> impl Fn(&'a [u8]) -> IResult<&'a [u8], Tag<&'a str, O>> where P: Fn(&'a [u8]) -> IResult<&'a [u8], O> { move |s: &[u8]| { let (s, tag) = sized('<', '|')(s)?; let (s, val) = inner(s)?; Ok((s, Tag { tag: std::str::from_utf8(tag) .map_err(|_| nom::Err::Failure((s, ErrorKind::Char)))?, val: Box::new(val) })) } } /// parse text scalar (`t5:hello,`) fn text(s: &[u8]) -> IResult<&[u8], T> { let (s, res) = text_g(s)?; Ok((s, T::Text(res.to_string()))) } fn text_g(s: &[u8]) -> IResult<&[u8], &str> { let (s, res) = sized('t', ',')(s)?; Ok((s, std::str::from_utf8(res) .map_err(|_| nom::Err::Failure((s, ErrorKind::Char)))?, )) } fn binary<'a>() -> impl Fn(&'a [u8]) -> IResult<&'a [u8], T> { map(binary_g(), |b| T::Binary(b.to_owned())) } fn binary_g() -> impl Fn(&[u8]) -> IResult<&[u8], &[u8]> { sized('b', ',') } fn list_t(s: &[u8]) -> IResult<&[u8], Vec<T>> { list_g(t_t)(s) } fn list_g<'a, P, O>(inner: P) -> impl Fn(&'a [u8]) -> IResult<&'a [u8], Vec<O>> where O: Clone, P: Fn(&'a [u8]) -> IResult<&'a [u8], O> { map_parser( sized('[', ']'), nom::multi::many0(inner) ) } fn record_t<'a>(s: &'a [u8]) -> IResult<&'a [u8], HashMap<String, T>> { let (s, r) = record_g(t_t)(s)?; Ok((s, r.into_iter() .map(|(k, v)| (k.to_string(), v)) .collect::<HashMap<_,_>>())) } fn record_g<'a, P, O>(inner: P) -> impl Fn(&'a [u8]) -> IResult<&'a [u8], HashMap<&'a str, O>> where O: Clone, P: Fn(&'a [u8]) -> IResult<&'a [u8], O> { map_parser( sized('{', '}'), nom::multi::fold_many1( tag_g(inner), HashMap::new(), |mut acc: HashMap<_,_>, Tag { tag, mut val }| { // ignore duplicated tag names that appear later // according to netencode spec if ! acc.contains_key(tag) { acc.insert(tag, *val); } acc } ) ) } pub fn u_u(s: &[u8]) -> IResult<&[u8], U> { alt(( map(text_g, U::Text), map(binary_g(), U::Binary), map(unit_t, |()| U::Unit), map(tag_g(u_u), |t| U::Sum(t)), map(list_g(u_u), U::List), map(record_g(u_u), U::Record), map(bool_t(), |u| U::N1(u)), map(uint_t("n3"), |u| U::N3(u)), map(uint_t("n6"), |u| U::N6(u)), map(uint_t("n7"), |u| U::N7(u)), map(int_t("i3"), |u| U::I3(u)), map(int_t("i6"), |u| U::I6(u)), map(int_t("i7"), |u| U::I7(u)), // less common map(uint_t("n2"), |u| U::N3(u)), map(uint_t("n4"), |u| U::N6(u)), map(uint_t("n5"), |u| U::N6(u)), map(int_t("i1"), |u| U::I3(u)), map(int_t("i2"), |u| U::I3(u)), map(int_t("i4"), |u| U::I6(u)), map(int_t("i5"), |u| U::I6(u)), // TODO: 8, 9 not supported ))(s) } pub fn t_t(s: &[u8]) -> IResult<&[u8], T> { alt(( text, binary(), map(unit_t, |_| T::Unit), map(tag_t, |t| T::Sum(t)), map(list_t, |l| T::List(l)), map(record_t, |p| T::Record(p)), map(bool_t(), |u| T::N1(u)), // 8, 64 and 128 bit map(uint_t("n3"), |u| T::N3(u)), map(uint_t("n6"), |u| T::N6(u)), map(uint_t("n7"), |u| T::N7(u)), map(int_t("i3"), |u| T::I3(u)), map(int_t("i6"), |u| T::I6(u)), map(int_t("i7"), |u| T::I7(u)), // less common map(uint_t("n2"), |u| T::N3(u)), map(uint_t("n4"), |u| T::N6(u)), map(uint_t("n5"), |u| T::N6(u)), map(int_t("i1"), |u| T::I3(u)), map(int_t("i2"), |u| T::I3(u)), map(int_t("i4"), |u| T::I6(u)), map(int_t("i5"), |u| T::I6(u)), // TODO: 8, 9 not supported ))(s) } #[cfg(test)] mod tests { use super::*; #[test] fn test_parse_unit_t() { assert_eq!( unit_t("u,".as_bytes()), Ok(("".as_bytes(), ())) ); } #[test] fn test_parse_bool_t() { assert_eq!( bool_t()("n1:0,".as_bytes()), Ok(("".as_bytes(), false)) ); assert_eq!( bool_t()("n1:1,".as_bytes()), Ok(("".as_bytes(), true)) ); } #[test] fn test_parse_usize_t() { assert_eq!( usize_t("32foo".as_bytes()), Ok(("foo".as_bytes(), 32)) ); } #[test] fn test_parse_int_t() { assert_eq!( uint_t::<u8>("n3")("n3:42,abc".as_bytes()), Ok(("abc".as_bytes(), 42)) ); assert_eq!( uint_t::<u8>("n3")("n3:1024,abc".as_bytes()), Err(nom::Err::Error(("1024,abc".as_bytes(), nom::error::ErrorKind::MapRes))) ); assert_eq!( int_t::<i64>("i6")("i6:-23,abc".as_bytes()), Ok(("abc".as_bytes(), -23)) ); assert_eq!( int_t::<i128>("i3")("i3:0,:abc".as_bytes()), Ok((":abc".as_bytes(), 0)) ); assert_eq!( uint_t::<u8>("n7")("n7:09,".as_bytes()), Ok(("".as_bytes(), 9)) ); // assert_eq!( // length("c"), // Err(nom::Err::Error(("c", nom::error::ErrorKind::Digit))) // ); // assert_eq!( // length(":"), // Err(nom::Err::Error((":", nom::error::ErrorKind::Digit))) // ); } #[test] fn test_parse_text() { assert_eq!( text("t5:hello,".as_bytes()), Ok(("".as_bytes(), T::Text("hello".to_owned()))) ); assert_eq!( text("t4:fo,".as_bytes()), // TODO: way better parse error messages Err(nom::Err::Error(("fo,".as_bytes(), nom::error::ErrorKind::Eof))) ); assert_eq!( text("t9:今日は,".as_bytes()), Ok(("".as_bytes(), T::Text("今日は".to_owned()))) ); } #[test] fn test_parse_binary() { assert_eq!( binary()("b5:hello,".as_bytes()), Ok(("".as_bytes(), T::Binary(Vec::from("hello".to_owned())))) ); assert_eq!( binary()("b4:fo,".as_bytes()), // TODO: way better parse error messages Err(nom::Err::Error(("fo,".as_bytes(), nom::error::ErrorKind::Eof))) ); assert_eq!( binary()("b9:今日は,".as_bytes()), Ok(("".as_bytes(), T::Binary(Vec::from("今日は".as_bytes())))) ); } #[test] fn test_list() { assert_eq!( list_t("[0:]".as_bytes()), Ok(("".as_bytes(), vec![])) ); assert_eq!( list_t("[6:u,u,u,]".as_bytes()), Ok(("".as_bytes(), vec![ T::Unit, T::Unit, T::Unit, ])) ); assert_eq!( list_t("[15:u,[7:t3:foo,]u,]".as_bytes()), Ok(("".as_bytes(), vec![ T::Unit, T::List(vec![T::Text("foo".to_owned())]), T::Unit, ])) ); } #[test] fn test_record() { assert_eq!( record_t("{21:<1:a|u,<1:b|u,<1:c|u,}".as_bytes()), Ok(("".as_bytes(), vec![ ("a".to_owned(), T::Unit), ("b".to_owned(), T::Unit), ("c".to_owned(), T::Unit), ].into_iter().collect::<HashMap<String, T>>())) ); // duplicated keys are ignored (first is taken) assert_eq!( record_t("{25:<1:a|u,<1:b|u,<1:a|i1:-1,}".as_bytes()), Ok(("".as_bytes(), vec![ ("a".to_owned(), T::Unit), ("b".to_owned(), T::Unit), ].into_iter().collect::<HashMap<_,_>>())) ); } #[test] fn test_parse() { assert_eq!( t_t("n3:255,".as_bytes()), Ok(("".as_bytes(), T::N3(255))) ); assert_eq!( t_t("t6:halloo,".as_bytes()), Ok(("".as_bytes(), T::Text("halloo".to_owned()))) ); assert_eq!( t_t("<3:foo|t6:halloo,".as_bytes()), Ok(("".as_bytes(), T::Sum (Tag { tag: "foo".to_owned(), val: Box::new(T::Text("halloo".to_owned())) }))) ); // { a: Unit // , foo: List <A: Unit | B: List i3> } assert_eq!( t_t("{52:<1:a|u,<3:foo|[33:<1:A|u,<1:A|n1:1,<1:B|[7:i3:127,]]}".as_bytes()), Ok(("".as_bytes(), T::Record(vec![ ("a".to_owned(), T::Unit), ("foo".to_owned(), T::List(vec![ T::Sum(Tag { tag: "A".to_owned(), val: Box::new(T::Unit) }), T::Sum(Tag { tag: "A".to_owned(), val: Box::new(T::N1(true)) }), T::Sum(Tag { tag: "B".to_owned(), val: Box::new(T::List(vec![T::I3(127)])) }), ])) ].into_iter().collect::<HashMap<String, T>>()))) ); } } } pub mod dec { use super::*; use std::collections::HashMap; pub struct DecodeError(pub String); pub trait Decoder<'a> { type A; fn dec(&self, u: U<'a>) -> Result<Self::A, DecodeError>; } #[derive(Clone, Copy)] pub struct AnyT; #[derive(Clone, Copy)] pub struct AnyU; impl<'a> Decoder<'a> for AnyT { type A = T; fn dec(&self, u: U<'a>) -> Result<Self::A, DecodeError> { Ok(u.to_t()) } } impl<'a> Decoder<'a> for AnyU { type A = U<'a>; fn dec(&self, u: U<'a>) -> Result<Self::A, DecodeError> { Ok(u) } } #[derive(Clone, Copy)] pub struct Text; // TODO: rename to Bytes #[derive(Clone, Copy)] pub struct Binary; impl<'a> Decoder<'a> for Text { type A = &'a str; fn dec(&self, u: U<'a>) -> Result<Self::A, DecodeError> { match u { U::Text(t) => Ok(t), other => Err(DecodeError(format!("Cannot decode {:?} into Text", other))), } } } impl<'a> Decoder<'a> for Binary { type A = &'a [u8]; fn dec(&self, u: U<'a>) -> Result<Self::A, DecodeError> { match u { U::Binary(b) => Ok(b), other => Err(DecodeError(format!("Cannot decode {:?} into Binary", other))), } } } #[derive(Clone, Copy)] pub struct ScalarAsBytes; impl<'a> Decoder<'a> for ScalarAsBytes { type A = Vec<u8>; fn dec(&self, u: U<'a>) -> Result<Self::A, DecodeError> { match u { U::N3(u) => Ok(format!("{}", u).into_bytes()), U::N6(u) => Ok(format!("{}", u).into_bytes()), U::N7(u) => Ok(format!("{}", u).into_bytes()), U::I3(i) => Ok(format!("{}", i).into_bytes()), U::I6(i) => Ok(format!("{}", i).into_bytes()), U::I7(i) => Ok(format!("{}", i).into_bytes()), U::Text(t) => Ok(t.as_bytes().to_owned()), U::Binary(b) => Ok(b.to_owned()), o => Err(DecodeError(format!("Cannot decode {:?} into scalar", o))), } } } #[derive(Clone, Copy)] pub struct Record<T>(pub T); impl<'a, Inner> Decoder<'a> for Record<Inner> where Inner: Decoder<'a> { type A = HashMap<&'a str, Inner::A>; fn dec(&self, u: U<'a>) -> Result<Self::A, DecodeError> { match u { U::Record(map) => map.into_iter() .map(|(k, v)| self.0.dec(v).map(|v2| (k, v2))) .collect::<Result<Self::A, _>>(), o => Err(DecodeError(format!("Cannot decode {:?} into record", o))) } } } #[derive(Clone, Copy)] pub struct RecordDot<'a, T> { pub field: &'a str, pub inner: T } impl <'a, Inner> Decoder<'a> for RecordDot<'_, Inner> where Inner: Decoder<'a> + Clone { type A = Inner::A; fn dec(&self, u: U<'a>) -> Result<Self::A, DecodeError> { match Record(self.inner.clone()).dec(u) { Ok(mut map) => match map.remove(self.field) { Some(inner) => Ok(inner), None => Err(DecodeError(format!("Cannot find `{}` in record map", self.field))), }, Err(err) => Err(err), } } } #[derive(Clone)] pub struct OneOf<T, A>{ pub inner: T, pub list: Vec<A>, } impl <'a, Inner> Decoder<'a> for OneOf<Inner, Inner::A> where Inner: Decoder<'a>, Inner::A: Display + Debug + PartialEq { type A = Inner::A; fn dec(&self, u: U<'a>) -> Result<Self::A, DecodeError> { match self.inner.dec(u) { Ok(inner) => match self.list.iter().any(|x| x.eq(&inner)) { true => Ok(inner), false => Err(DecodeError(format!("{} is not one of {:?}", inner, self.list))) }, Err(err) => Err(err) } } } #[derive(Clone)] pub struct Try<T>(pub T); impl <'a, Inner> Decoder<'a> for Try<Inner> where Inner: Decoder<'a> { type A = Option<Inner::A>; fn dec(&self, u: U<'a>) -> Result<Self::A, DecodeError> { match self.0.dec(u) { Ok(inner) => Ok(Some(inner)), Err(err) => Ok(None) } } } }