devd_rs/
parser.rs

1use crate::data::*;
2
3use nom::{
4    branch::alt,
5    bytes::complete::{tag, take_while},
6    character::complete::{alphanumeric1, char, multispace0, multispace1},
7    combinator::success,
8    multi::fold_many0,
9    sequence::{delimited, preceded, terminated, tuple},
10    IResult, Parser,
11};
12
13/// Parse a single value, which is either a quoted string, or a word without whitespace
14fn val(input: &str) -> IResult<&str, &str, ()> {
15    alt((delimited(char('"'), take_while(|c| c != '"'), char('"')), take_while(|c| c != '\n' && c != ' '))).parse(input)
16}
17
18/// Parse a key followed by a value, separated by =
19fn keyval(input: &str) -> IResult<&str, (&str, &str), ()> {
20    terminated(alphanumeric1, char('=')).and(val).parse(input)
21}
22
23/// Parser any number of key-value pairs, separated by 0 or more whitespace
24fn keyvals(input: &str) -> IResult<&str, BTreeMap<String, String>, ()> {
25    fold_many0(terminated(keyval, multispace0), BTreeMap::new, |mut map, (key, value)| {
26        map.insert(key.to_owned(), value.to_owned());
27        map
28    })
29    .parse(input)
30}
31
32/// Parse a key-value pair, where the key is a specific tag, separated by =,
33/// terminated by whitespace
34fn keyed_val<'i>(key: &'static str) -> impl Parser<&'i str, &'i str, ()> {
35    terminated(preceded(terminated(tag(key), char('=')), val), multispace1)
36}
37
38fn notify(input: &str) -> IResult<&str, Event, ()> {
39    preceded(char('!'), tuple((keyed_val("system"), keyed_val("subsystem"), keyed_val("type"), keyvals)))
40        .map(|(sys, subsys, kind, data)| Event::Notify {
41            system: sys.to_owned(),
42            subsystem: subsys.to_owned(),
43            kind: kind.to_owned(),
44            data,
45        })
46        .parse(input)
47}
48
49/// Parse a key-value pair, where the key is a specific tag, separated by
50/// whitespace
51fn event_param<'i, T>(key: &'static str, value: impl Parser<&'i str, T, ()>) -> impl Parser<&'i str, T, ()> {
52    preceded(terminated(tag(key), multispace1), value)
53}
54
55fn generic_event<'i, T>(prefix: char, dev: impl Parser<&'i str, T, ()>) -> impl Parser<&'i str, (T, BTreeMap<String, String>, &'i str), ()> {
56    tuple((
57        terminated(preceded(char(prefix), dev), multispace1),
58        event_param("at", keyvals),
59        event_param("on", val),
60    ))
61}
62
63fn attach(input: &str) -> IResult<&str, Event, ()> {
64    generic_event('+', alphanumeric1).map(|(dev, parent, loc)| Event::Attach { dev: dev.to_owned(), parent, location: loc.to_owned() }).parse(input)
65}
66
67fn detach(input: &str) -> IResult<&str, Event, ()> {
68    generic_event('-', alphanumeric1).map(|(dev, parent, loc)| Event::Detach { dev: dev.to_owned(), parent, location: loc.to_owned() }).parse(input)
69}
70
71fn nomatch(input: &str) -> IResult<&str, Event, ()> {
72    generic_event('?', success(())).map(|((), parent, loc)| Event::Nomatch { parent, location: loc.to_owned() }).parse(input)
73}
74
75pub fn event(input: &str) -> IResult<&str, Event, ()> {
76    alt((notify, attach, detach, nomatch)).parse(input)
77}
78
79#[cfg(test)]
80mod tests {
81    use super::*;
82
83    #[test]
84    fn test_notify() {
85        let txt = "!system=USB subsystem=INTERFACE type=ATTACH ugen=ugen0.2 vendor=0x1050 sernum=\"\" mode=host\n";
86        let res = event(txt);
87        let mut data = BTreeMap::new();
88        data.insert("ugen".to_owned(), "ugen0.2".to_owned());
89        data.insert("vendor".to_owned(), "0x1050".to_owned());
90        data.insert("sernum".to_owned(), "".to_owned());
91        data.insert("mode".to_owned(), "host".to_owned());
92        assert_eq!(
93            res,
94            Ok((
95                "",
96                Event::Notify {
97                    system: "USB".to_owned(),
98                    subsystem: "INTERFACE".to_owned(),
99                    kind: "ATTACH".to_owned(),
100                    data,
101                }
102            ))
103        )
104    }
105
106    #[test]
107    fn test_attach() {
108        let txt = "+uhid1 at bus=0 sernum=\"\" on uhub1";
109        let res = event(txt);
110        let mut data = BTreeMap::new();
111        data.insert("bus".to_owned(), "0".to_owned());
112        data.insert("sernum".to_owned(), "".to_owned());
113        assert_eq!(
114            res,
115            Ok((
116                "",
117                Event::Attach {
118                    dev: "uhid1".to_owned(),
119                    parent: data,
120                    location: "uhub1".to_owned(),
121                }
122            ))
123        )
124    }
125
126    #[test]
127    fn test_detach() {
128        let txt = "-uhid1 at  on uhub1";
129        let res = event(txt);
130        let data = BTreeMap::new();
131        assert_eq!(
132            res,
133            Ok((
134                "",
135                Event::Detach {
136                    dev: "uhid1".to_owned(),
137                    parent: data,
138                    location: "uhub1".to_owned(),
139                }
140            ))
141        )
142    }
143
144    #[test]
145    fn test_nomatch() {
146        let txt = "? at bus=0 on uhub1";
147        let res = event(txt);
148        let mut data = BTreeMap::new();
149        data.insert("bus".to_owned(), "0".to_owned());
150
151        assert_eq!(res, Ok(("", Event::Nomatch { parent: data, location: "uhub1".to_owned() })))
152    }
153}
devd_rs/parser.rs

devd_rs/
parser.rs
