1 files changed, 153 insertions, 0 deletions
diff --git a/third_party/rust/devd-rs/src/parser.rs b/third_party/rust/devd-rs/src/parser.rs
new file mode 100644
index 0000000000..ee3c0511e9
--- /dev/null
+++ b/third_party/rust/devd-rs/src/parser.rs
@@ -0,0 +1,153 @@
+use crate::data::*;
+
+use nom::{
+    branch::alt,
+    bytes::complete::{tag, take_while},
+    character::complete::{alphanumeric1, char, multispace0, multispace1},
+    combinator::success,
+    multi::fold_many0,
+    sequence::{delimited, preceded, terminated, tuple},
+    IResult, Parser,
+};
+
+/// Parse a single value, which is either a quoted string, or a word without whitespace
+fn val(input: &str) -> IResult<&str, &str, ()> {
+    alt((delimited(char('"'), take_while(|c| c != '"'), char('"')), take_while(|c| c != '\n' && c != ' '))).parse(input)
+}
+
+/// Parse a key followed by a value, separated by =
+fn keyval(input: &str) -> IResult<&str, (&str, &str), ()> {
+    terminated(alphanumeric1, char('=')).and(val).parse(input)
+}
+
+/// Parser any number of key-value pairs, separated by 0 or more whitespace
+fn keyvals(input: &str) -> IResult<&str, BTreeMap<String, String>, ()> {
+    fold_many0(terminated(keyval, multispace0), BTreeMap::new, |mut map, (key, value)| {
+        map.insert(key.to_owned(), value.to_owned());
+        map
+    })
+    .parse(input)
+}
+
+/// Parse a key-value pair, where the key is a specific tag, separated by =,
+/// terminated by whitespace
+fn keyed_val<'i>(key: &'static str) -> impl Parser<&'i str, &'i str, ()> {
+    terminated(preceded(terminated(tag(key), char('=')), val), multispace1)
+}
+
+fn notify(input: &str) -> IResult<&str, Event, ()> {
+    preceded(char('!'), tuple((keyed_val("system"), keyed_val("subsystem"), keyed_val("type"), keyvals)))
+        .map(|(sys, subsys, kind, data)| Event::Notify {
+            system: sys.to_owned(),
+            subsystem: subsys.to_owned(),
+            kind: kind.to_owned(),
+            data,
+        })
+        .parse(input)
+}
+
+/// Parse a key-value pair, where the key is a specific tag, separated by
+/// whitespace
+fn event_param<'i, T>(key: &'static str, value: impl Parser<&'i str, T, ()>) -> impl Parser<&'i str, T, ()> {
+    preceded(terminated(tag(key), multispace1), value)
+}
+
+fn generic_event<'i, T>(prefix: char, dev: impl Parser<&'i str, T, ()>) -> impl Parser<&'i str, (T, BTreeMap<String, String>, &'i str), ()> {
+    tuple((
+        terminated(preceded(char(prefix), dev), multispace1),
+        event_param("at", keyvals),
+        event_param("on", val),
+    ))
+}
+
+fn attach(input: &str) -> IResult<&str, Event, ()> {
+    generic_event('+', alphanumeric1).map(|(dev, parent, loc)| Event::Attach { dev: dev.to_owned(), parent, location: loc.to_owned() }).parse(input)
+}
+
+fn detach(input: &str) -> IResult<&str, Event, ()> {
+    generic_event('-', alphanumeric1).map(|(dev, parent, loc)| Event::Detach { dev: dev.to_owned(), parent, location: loc.to_owned() }).parse(input)
+}
+
+fn nomatch(input: &str) -> IResult<&str, Event, ()> {
+    generic_event('?', success(())).map(|((), parent, loc)| Event::Nomatch { parent, location: loc.to_owned() }).parse(input)
+}
+
+pub fn event(input: &str) -> IResult<&str, Event, ()> {
+    alt((notify, attach, detach, nomatch)).parse(input)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_notify() {
+        let txt = "!system=USB subsystem=INTERFACE type=ATTACH ugen=ugen0.2 vendor=0x1050 sernum=\"\" mode=host\n";
+        let res = event(txt);
+        let mut data = BTreeMap::new();
+        data.insert("ugen".to_owned(), "ugen0.2".to_owned());
+        data.insert("vendor".to_owned(), "0x1050".to_owned());
+        data.insert("sernum".to_owned(), "".to_owned());
+        data.insert("mode".to_owned(), "host".to_owned());
+        assert_eq!(
+            res,
+            Ok((
+                "",
+                Event::Notify {
+                    system: "USB".to_owned(),
+                    subsystem: "INTERFACE".to_owned(),
+                    kind: "ATTACH".to_owned(),
+                    data,
+                }
+            ))
+        )
+    }
+
+    #[test]
+    fn test_attach() {
+        let txt = "+uhid1 at bus=0 sernum=\"\" on uhub1";
+        let res = event(txt);
+        let mut data = BTreeMap::new();
+        data.insert("bus".to_owned(), "0".to_owned());
+        data.insert("sernum".to_owned(), "".to_owned());
+        assert_eq!(
+            res,
+            Ok((
+                "",
+                Event::Attach {
+                    dev: "uhid1".to_owned(),
+                    parent: data,
+                    location: "uhub1".to_owned(),
+                }
+            ))
+        )
+    }
+
+    #[test]
+    fn test_detach() {
+        let txt = "-uhid1 at  on uhub1";
+        let res = event(txt);
+        let data = BTreeMap::new();
+        assert_eq!(
+            res,
+            Ok((
+                "",
+                Event::Detach {
+                    dev: "uhid1".to_owned(),
+                    parent: data,
+                    location: "uhub1".to_owned(),
+                }
+            ))
+        )
+    }
+
+    #[test]
+    fn test_nomatch() {
+        let txt = "? at bus=0 on uhub1";
+        let res = event(txt);
+        let mut data = BTreeMap::new();
+        data.insert("bus".to_owned(), "0".to_owned());
+
+        assert_eq!(res, Ok(("", Event::Nomatch { parent: data, location: "uhub1".to_owned() })))
+    }
+}