start new parser

Cargo.toml

@@ -16,7 +16,8 @@ hex = "0.4"
 err-derive = "0.3"
 
 dryoc = { version = "0.4", optional = true }
-serde = { version = "1.0", optional = true, features = ["derive"] }
+serde = { version = "1.0", optional = true, default-features = false, features = ["derive"] }
 
 [features]
-default = [ "dryoc", "serde" ]
+#default = [ "dryoc", "serde" ]
+#default = [ "serde" ]

src/buf.rs

@@ -0,0 +1,561 @@
+use std::borrow::Cow;
+
+use crate::{
+    is_string_char, is_whitespace, DICT_ASSIGN, DICT_CLOSE, DICT_DELIM, DICT_OPEN, LIST_CLOSE,
+    LIST_DELIM, LIST_OPEN,
+};
+
+pub type Pos = u32;
+
+#[derive(Debug)]
+pub enum ParseError {
+    IncompleteInput,
+    DuplicateKey(Pos),
+    Garbage(Pos),
+}
+
+#[derive(Clone, Copy, Debug)]
+pub struct ITerm(Pos);
+
+#[derive(Clone, Copy, Debug)]
+struct IRaw {
+    start: Pos,
+    end: Pos,
+}
+
+#[derive(Clone, Copy, Debug)]
+struct ISeq {
+    seq_start: Pos,
+    seq_end: Pos,
+}
+
+#[derive(Clone, Copy, Debug)]
+struct IDict {
+    dict_start: Pos,
+    dict_end: Pos,
+}
+
+#[derive(Debug)]
+enum TTerm {
+    Str(IRaw),
+    RawSeq(IRaw, ISeq),
+    RawList(IRaw, ISeq),
+    RawDict(IRaw, IDict),
+}
+
+#[derive(Debug)]
+pub struct Buf<'a> {
+    bytes: Cow<'a, [u8]>,
+    seqs: Vec<ITerm>,
+    dicts: Vec<(IRaw, ITerm)>,
+    terms: Vec<TTerm>,
+}
+
+pub fn decode(input: &[u8]) -> Result<(Buf<'_>, ITerm), ParseError> {
+    let mut buf = Buf {
+        bytes: input.into(),
+        seqs: Vec::with_capacity(16),
+        dicts: Vec::with_capacity(16),
+        terms: Vec::with_capacity(16),
+    };
+    let all_buf = IRaw {
+        start: 0,
+        end: input.len() as Pos,
+    };
+
+    let mut stack = Vec::with_capacity(16);
+    let (term, rest) = buf.decode(all_buf, &mut stack)?;
+    assert!(stack.is_empty());
+
+    let rest = buf.take_whitespace(rest);
+    if rest.start < all_buf.end {
+        return Err(ParseError::Garbage(rest.start));
+    }
+
+    Ok((buf, term))
+}
+
+enum StackItem {
+    Term(ITerm),
+    KeyValue(IRaw, ITerm),
+}
+type Stack = Vec<StackItem>;
+impl StackItem {
+    fn term(self) -> ITerm {
+        match self {
+            StackItem::Term(term) => term,
+            _ => unreachable!(),
+        }
+    }
+    fn kv(self) -> (IRaw, ITerm) {
+        match self {
+            StackItem::KeyValue(key, term) => (key, term),
+            _ => unreachable!(),
+        }
+    }
+}
+
+impl<'a> Buf<'a> {
+    // ============================================ PUBLIC ACCESS FUNCTIONS
+
+    pub fn raw(&self, term: ITerm) -> Option<&[u8]> {
+        match self.terms.get(term.0 as usize)? {
+            TTerm::Str(r) | TTerm::RawSeq(r, _) | TTerm::RawList(r, _) | TTerm::RawDict(r, _) => {
+                self.get_bytes(*r)
+            }
+        }
+    }
+
+    pub fn str(&self, term: ITerm) -> Option<&str> {
+        match self.terms.get(term.0 as usize)? {
+            TTerm::Str(r) => self
+                .bytes
+                .get(r.start as usize..r.end as usize)
+                .map(|x| unsafe { std::str::from_utf8_unchecked(x) }),
+            _ => None,
+        }
+    }
+
+    pub fn seq<'x>(&'x self, term: &'x ITerm) -> Option<&'x [ITerm]> {
+        match self.terms.get(term.0 as usize)? {
+            TTerm::RawSeq(_, s) => self.seqs.get(s.seq_start as usize..s.seq_end as usize),
+            _ => Some(std::slice::from_ref(term)),
+        }
+    }
+
+    pub fn seq_of<const N: usize>(&self, term: ITerm) -> Option<[ITerm; N]> {
+        match self.terms.get(term.0 as usize)? {
+            TTerm::RawSeq(_, s) => {
+                if (s.seq_end - s.seq_start) as usize == N {
+                    let seq = self.seqs.get(s.seq_start as usize..s.seq_end as usize)?;
+                    Some(seq.try_into().unwrap())
+                } else {
+                    None
+                }
+            }
+            _ => None,
+        }
+    }
+
+    pub fn list(&self, term: ITerm) -> Option<&[ITerm]> {
+        match self.terms.get(term.0 as usize)? {
+            TTerm::RawList(_, s) => self.seqs.get(s.seq_start as usize..s.seq_end as usize),
+            _ => None,
+        }
+    }
+
+    pub fn list_of<const N: usize>(&self, term: ITerm) -> Option<[ITerm; N]> {
+        match self.terms.get(term.0 as usize)? {
+            TTerm::RawList(_, s) if (s.seq_end - s.seq_start) as usize == N => {
+                let seq = self.seqs.get(s.seq_start as usize..s.seq_end as usize)?;
+                Some(seq.try_into().unwrap())
+            }
+            _ => None,
+        }
+    }
+
+    pub fn dict_get(&self, term: ITerm, key: &str) -> Option<ITerm> {
+        match self.terms.get(term.0 as usize)? {
+            TTerm::RawDict(_, d) => {
+                let dict = self.dicts.get(d.dict_start as usize..d.dict_end as usize)?;
+                let pos = dict.binary_search_by(|(k, _)| self.get_bytes(*k).unwrap().cmp(key.as_bytes())).ok()?;
+                Some(dict[pos].1)
+            }
+            _ => None,
+        }
+    }
+
+    pub fn dict_of<const N: usize>(&self, term: ITerm, keys: [&str; N], allow_other: bool) -> Option<[ITerm; N]> {
+        match self.terms.get(term.0 as usize)? {
+            TTerm::RawDict(_, d) => {
+                let dict = self.dicts.get(d.dict_start as usize..d.dict_end as usize)?;
+                if dict.len() < N || (dict.len() > N && !allow_other) {
+                    return None;
+                }
+
+                let mut ret = [ITerm(0); N];
+                for i in 0..N {
+                    let pos = dict.binary_search_by(|(k, _)| self.get_bytes(*k).unwrap().cmp(keys[i].as_bytes())).ok()?;
+                    ret[i] = dict[pos].1;
+                }
+
+                Some(ret)
+            }
+            _ => None,
+        }
+    }
+
+    pub fn dict_iter(&self, term: ITerm) -> Option<impl Iterator<Item=(&str, ITerm)> + '_> {
+        match self.terms.get(term.0 as usize)? {
+            TTerm::RawDict(_, d) => {
+                let dict = self.dicts.get(d.dict_start as usize..d.dict_end as usize)?;
+                let iter = dict.iter().map(|(k, v)| (unsafe { std::str::from_utf8_unchecked(self.get_bytes(*k).unwrap()) }, *v));
+                Some(iter)
+            }
+            _ => None,
+        }
+    }
+
+    // ============================================ NETTEXT PARSING
+
+    fn decode(&mut self, raw: IRaw, stack: &mut Stack) -> Result<(ITerm, IRaw), ParseError> {
+        let start = self.take_whitespace(raw);
+        let stack_start = stack.len();
+
+        let mut cur_end = start;
+        let mut next_start = start;
+        loop {
+            match self.decode_nonseq_term(next_start, stack) {
+                Err(_) => break,
+                Ok((term, rest)) => {
+                    stack.push(StackItem::Term(term));
+                    cur_end = rest;
+                    next_start = self.take_whitespace(rest);
+                }
+            }
+        }
+
+        if stack.len() == stack_start {
+            Err(self.error_at(next_start))
+        } else if stack.len() == stack_start + 1 {
+            Ok((stack.pop().unwrap().term(), next_start))
+        } else {
+            let seq_raw = IRaw {
+                start: start.start,
+                end: cur_end.start,
+            };
+            let seq_start = self.seqs.len();
+            self.seqs
+                .extend(stack.drain(stack_start..).map(StackItem::term));
+            let seq = TTerm::RawSeq(
+                seq_raw,
+                ISeq {
+                    seq_start: seq_start as Pos,
+                    seq_end: self.seqs.len() as Pos,
+                },
+            );
+            Ok((self.push_term(seq), next_start))
+        }
+    }
+
+    fn decode_nonseq_term(
+        &mut self,
+        raw: IRaw,
+        stack: &mut Stack,
+    ) -> Result<(ITerm, IRaw), ParseError> {
+        if let Ok((term, rest)) = self.decode_string(raw) {
+            Ok((term, rest))
+        } else if let Ok((term, rest)) = self.decode_list(raw, stack) {
+            Ok((term, rest))
+        } else if let Ok((term, rest)) = self.decode_dict(raw, stack) {
+            Ok((term, rest))
+        } else {
+            Err(self.error_at(raw))
+        }
+    }
+
+    fn decode_list(&mut self, raw: IRaw, stack: &mut Stack) -> Result<(ITerm, IRaw), ParseError> {
+        let stack_start = stack.len();
+
+        let mut cur = self.take_whitespace(self.take_char(raw, LIST_OPEN)?);
+
+        while let Ok((term, rest)) = self.decode(cur, stack) {
+            stack.push(StackItem::Term(term));
+            cur = self.take_whitespace(rest);
+            if let Ok(rest) = self.take_char(rest, LIST_DELIM) {
+                cur = self.take_whitespace(rest);
+            } else {
+                break;
+            }
+        }
+
+        if let Ok(rest) = self.take_char(cur, LIST_CLOSE) {
+            let seq_raw = IRaw {
+                start: raw.start,
+                end: rest.start,
+            };
+            let seq_start = self.seqs.len();
+            self.seqs
+                .extend(stack.drain(stack_start..).map(StackItem::term));
+            let seq = TTerm::RawList(
+                seq_raw,
+                ISeq {
+                    seq_start: seq_start as Pos,
+                    seq_end: self.seqs.len() as Pos,
+                },
+            );
+            Ok((self.push_term(seq), rest))
+        } else {
+            stack.truncate(stack_start);
+            Err(self.error_at(cur))
+        }
+    }
+
+    fn decode_dict(&mut self, raw: IRaw, stack: &mut Stack) -> Result<(ITerm, IRaw), ParseError> {
+        let stack_start = stack.len();
+
+        match self.decode_dict_inner(raw, stack) {
+            Ok(rest) => {
+                let dict_raw = IRaw {
+                    start: raw.start,
+                    end: rest.start,
+                };
+                let dict_start = self.dicts.len();
+                self.dicts
+                    .extend(stack.drain(stack_start..).map(StackItem::kv));
+                self.dicts[dict_start..]
+                    .sort_by_key(|(k, _)| (&self.bytes[k.start as usize..k.end as usize], k.start));
+
+                for ((k1, _), (k2, _)) in self.dicts[dict_start..]
+                    .iter()
+                    .zip(self.dicts[dict_start + 1..].iter())
+                {
+                    if self.get_bytes(*k1).unwrap() == self.get_bytes(*k2).unwrap() {
+                        return Err(ParseError::DuplicateKey(k1.start));
+                    }
+                }
+
+                let dict = TTerm::RawDict(
+                    dict_raw,
+                    IDict {
+                        dict_start: dict_start as Pos,
+                        dict_end: self.dicts.len() as Pos,
+                    },
+                );
+                Ok((self.push_term(dict), rest))
+            }
+            Err(e) => {
+                stack.truncate(stack_start);
+                Err(e)
+            }
+        }
+    }
+
+    fn decode_dict_inner(&mut self, raw: IRaw, stack: &mut Stack) -> Result<IRaw, ParseError> {
+        let mut cur = self.take_whitespace(self.take_char(raw, DICT_OPEN)?);
+
+        while let Ok((key, rest)) = self.take_string(cur) {
+            cur = self.take_whitespace(rest);
+
+            cur = self.take_char(cur, DICT_ASSIGN)?;
+
+            let (value, rest) = self.decode(cur, stack)?;
+            cur = self.take_whitespace(rest);
+            stack.push(StackItem::KeyValue(key, value));
+
+            if let Ok(rest) = self.take_char(cur, DICT_DELIM) {
+                cur = self.take_whitespace(rest);
+            } else {
+                break;
+            }
+        }
+
+        let rest = self.take_char(cur, DICT_CLOSE)?;
+        Ok(rest)
+    }
+
+    fn decode_string(&mut self, raw: IRaw) -> Result<(ITerm, IRaw), ParseError> {
+        let (string_raw, rest) = self.take_string(raw)?;
+        let string = self.push_term(TTerm::Str(string_raw));
+        Ok((string, rest))
+    }
+
+    fn take_string(&mut self, raw: IRaw) -> Result<(IRaw, IRaw), ParseError> {
+        let mut rest = raw;
+        while rest.start < rest.end {
+            if is_string_char(self.bytes[rest.start as usize]) {
+                rest.start += 1;
+            } else {
+                break;
+            }
+        }
+
+        if rest.start > raw.start {
+            let string_raw = IRaw {
+                start: raw.start,
+                end: rest.start,
+            };
+            Ok((string_raw, rest))
+        } else {
+            Err(self.error_at(rest))
+        }
+    }
+
+    #[inline]
+    fn take_char(&self, raw: IRaw, c: u8) -> Result<IRaw, ParseError> {
+        if raw.start >= raw.end {
+            Err(ParseError::IncompleteInput)
+        } else if self.bytes[raw.start as usize] != c {
+            Err(ParseError::Garbage(raw.start))
+        } else {
+            Ok(IRaw {
+                start: raw.start + 1,
+                end: raw.end,
+            })
+        }
+    }
+
+    #[inline]
+    fn take_whitespace(&self, mut raw: IRaw) -> IRaw {
+        while raw.start < raw.end {
+            if is_whitespace(self.bytes[raw.start as usize]) {
+                raw.start += 1;
+            } else {
+                break;
+            }
+        }
+        raw
+    }
+
+    #[inline]
+    fn get_bytes(&self, raw: IRaw) -> Option<&[u8]> {
+        self.bytes.get(raw.start as usize..raw.end as usize)
+    }
+
+    #[inline]
+    fn error_at(&self, raw: IRaw) -> ParseError {
+        if raw.start < raw.end {
+            ParseError::Garbage(raw.start)
+        } else {
+            ParseError::IncompleteInput
+        }
+    }
+
+    #[inline]
+    fn push_term(&mut self, term: TTerm) -> ITerm {
+        let ret = ITerm(self.terms.len() as Pos);
+        self.terms.push(term);
+        ret
+    }
+
+    #[cfg(test)]
+    fn debug(&self, i: ITerm) {
+        use crate::debug as debug_str;
+
+        let term = &self.terms[i.0 as usize];
+        match term {
+            TTerm::Str(r) => {
+                eprintln!(
+                    "{} -> {:?} = `{}`",
+                    i.0,
+                    term,
+                    debug_str(&self.bytes[r.start as usize..r.end as usize])
+                );
+            }
+            TTerm::RawSeq(r, s) => {
+                eprintln!(
+                    "{} -> {:?} = `{}` ((",
+                    i.0,
+                    term,
+                    debug_str(&self.bytes[r.start as usize..r.end as usize])
+                );
+                for j in self.seqs[s.seq_start as usize..s.seq_end as usize].iter() {
+                    self.debug(*j);
+                }
+                eprintln!("))");
+            }
+            TTerm::RawList(r, l) => {
+                eprintln!(
+                    "{} -> {:?} = `{}` [[",
+                    i.0,
+                    term,
+                    debug_str(&self.bytes[r.start as usize..r.end as usize])
+                );
+                for j in self.seqs[l.seq_start as usize..l.seq_end as usize].iter() {
+                    self.debug(*j);
+                }
+                eprintln!("]]");
+            }
+            TTerm::RawDict(r, d) => {
+                eprintln!(
+                    "{} -> {:?} = `{}` {{{{",
+                    i.0,
+                    term,
+                    debug_str(&self.bytes[r.start as usize..r.end as usize])
+                );
+                for (k, v) in self.dicts[d.dict_start as usize..d.dict_end as usize].iter() {
+                    eprint!(
+                        "[`{}`] = ",
+                        debug_str(&self.bytes[k.start as usize..k.end as usize])
+                    );
+                    self.debug(*v);
+                }
+                eprintln!("}}}}");
+            }
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn list_and_seq() {
+        let string = "[ [ h1; h2; h3 ]; hello world [ acc bii; cooj   dlpa] ]";
+        eprintln!("{}", string);
+        let (buf, term) = decode(string.as_bytes()).unwrap();
+        buf.debug(term);
+
+        let [a, b] = buf.list_of(term).unwrap();
+
+        assert_eq!(buf.raw(a).unwrap(), b"[ h1; h2; h3 ]");
+        let l = buf.list(a).unwrap();
+        assert_eq!(l.len(), 3);
+        assert_eq!(buf.str(l[0]).unwrap(), "h1");
+        assert_eq!(buf.str(l[1]).unwrap(), "h2");
+        assert_eq!(buf.str(l[2]).unwrap(), "h3");
+
+        assert_eq!(buf.raw(b).unwrap(), b"hello world [ acc bii; cooj   dlpa]");
+        let [h, w, l] = buf.seq_of(b).unwrap();
+        assert_eq!(buf.str(h).unwrap(), "hello");
+        assert_eq!(buf.str(w).unwrap(), "world");
+
+        assert_eq!(buf.raw(l).unwrap(), b"[ acc bii; cooj   dlpa]");
+        let [l1, l2] = buf.list_of(l).unwrap();
+
+        assert_eq!(buf.raw(l1).unwrap(), b"acc bii");
+        let s = buf.seq(&l1).unwrap();
+        assert_eq!(s.len(), 2);
+        assert_eq!(buf.str(s[0]).unwrap(), "acc");
+        assert_eq!(buf.str(s[1]).unwrap(), "bii");
+
+        assert_eq!(buf.raw(l2).unwrap(), b"cooj   dlpa");
+        let [s2a, s2b] = buf.seq_of(l2).unwrap();
+        assert_eq!(buf.str(s2a).unwrap(), "cooj");
+        assert_eq!(buf.str(s2b).unwrap(), "dlpa");
+    }
+
+    #[test]
+    fn dict() {
+        let string =
+            "[ { a = plop; b = hello world }; ploplop { e=15; d=12 ;c = {key=val;key2=val2}} ]";
+        eprintln!("{}", string);
+        let (buf, term) = decode(string.as_bytes()).unwrap();
+        buf.debug(term);
+
+        let [a, b] = buf.list_of(term).unwrap();
+        
+        assert_eq!(buf.raw(a).unwrap(), b"{ a = plop; b = hello world }");
+        let [aa, ab] = buf.dict_of(a, ["a", "b"], false).unwrap();
+        assert_eq!(buf.raw(aa).unwrap(), b"plop");
+        assert_eq!(buf.raw(ab).unwrap(), b"hello world");
+
+        assert_eq!(buf.raw(b).unwrap(), b"ploplop { e=15; d=12 ;c = {key=val;key2=val2}}");
+        let [ba, bb] = buf.seq_of(b).unwrap();
+        assert_eq!(buf.str(ba).unwrap(), "ploplop");
+
+        assert_eq!(buf.str(buf.dict_get(bb, "e").unwrap()).unwrap(), "15");
+        let mut iter = buf.dict_iter(bb).unwrap();
+        let (k1, v1) = iter.next().unwrap();
+        assert_eq!(k1, "c");
+        assert_eq!(buf.raw(v1).unwrap(), b"{key=val;key2=val2}");
+        let (k2, v2) = iter.next().unwrap();
+        assert_eq!(k2, "d");
+        assert_eq!(buf.str(v2).unwrap(), "12");
+        let (k3, v3) = iter.next().unwrap();
+        assert_eq!(k3, "e");
+        assert_eq!(buf.str(v3).unwrap(), "15");
+        assert!(iter.next().is_none());
+    }
+}

src/enc/mod.rs

@@ -22,8 +22,8 @@ mod error;
 use std::borrow::{Borrow, Cow};
 use std::collections::HashMap;
 
-use crate::*;
 use crate::dec::{self, decode};
+use crate::*;
 use crate::{is_string_char, is_whitespace, switch64, BytesEncoding};
 
 pub use error::Error;

src/lib.rs

@@ -84,6 +84,7 @@
 //! Note that the value of `text1` is embedded as-is inside `text2`. This is what allows us
 //! to check the hash and the signature: the raw representation of the term hasn't changed.
 
+pub mod buf;
 pub mod dec;
 pub mod enc;
 pub mod switch64;

src/switch64.rs

@@ -103,10 +103,7 @@ mod tests {
     #[test]
     fn test_encode() {
         assert_eq!(debug(&encode(&b"hello world"[..], true)), "hello world");
-        assert_eq!(
-            debug(&encode(&b"hello, world!"[..], true)),
-            "hello, world!"
-        );
+        assert_eq!(debug(&encode(&b"hello, world!"[..], true)), "hello, world!");
     }
 
     #[test]