printenv2 0.0.3

A printenv rewrite in Rust
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136

use crate::args::KeyOrder;
use crate::platform_ext;
use std::cmp::Ordering;
use std::slice::Iter;

#[derive(Eq, Debug)]
pub struct RecordPair(pub Vec<u8>, pub Vec<u8>);

impl PartialEq<Self> for RecordPair {
    fn eq(&self, other: &Self) -> bool {
        self.0.eq(&other.0)
    }
}

impl PartialOrd<Self> for RecordPair {
    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
        Some(self.cmp(other))
    }
}

impl Ord for RecordPair {
    fn cmp(&self, other: &Self) -> Ordering {
        self.0.cmp(&other.0)
    }
}

#[derive(Debug, PartialEq)]
pub struct Env(pub Vec<RecordPair>);

impl Env {
    pub fn iter(&self) -> Iter<'_, RecordPair> {
        self.0.iter()
    }

    pub fn sort_by_key(&mut self, key_order: KeyOrder) {
        // Sort results if needed
        match key_order {
            KeyOrder::Asc => {
                self.0.sort();
            }
            KeyOrder::Desc => {
                self.0.sort_by(|a, b| b.cmp(a));
            }
        }
    }
}

#[cfg(remote_env)]
pub mod remote {
    use crate::AppResult;
    pub fn get_environment_string(pid: u32) -> AppResult<Vec<u8>> {
        #[cfg(target_os = "linux")]
        {
            crate::remote_linux_procfs::get_environment_string(pid)
        }

        #[cfg(unix_kvm)]
        {
            crate::remote_unix_kvm::get_environment_string(pid)
        }

        #[cfg(target_family = "windows")]
        {
            crate::remote_windows::get_environment_string(pid)
        }
    }

    #[test]
    fn test_get_environment_string() {
        use crate::args::ColorMode;
        use crate::printer::Printer;

        let actual = get_environment_string(std::process::id()).unwrap();
        let expected = super::Env::new();
        let printer = Printer {
            null: true,
            color: ColorMode::Never,
            ..Default::default()
        };
        assert_eq!(actual, printer.print(&expected).unwrap());
    }
}

fn parse_record_pair(record: &[u8]) -> Option<RecordPair> {
    record
        .iter()
        .position(|c| b'=' == *c)
        .map(|i| RecordPair((&record[..i]).to_vec(), (&record[i + 1..]).to_vec()))
}

impl From<Vec<u8>> for Env {
    fn from(env_string: Vec<u8>) -> Self {
        Self(
            env_string
                .split(|c| *c == 0)
                .filter_map(parse_record_pair)
                .collect(),
        )
    }
}

impl Env {
    pub fn new() -> Self {
        Self(
            std::env::vars_os()
                .map(|(key, value)| {
                    RecordPair(
                        platform_ext::os_string_to_u8_vec(&key),
                        platform_ext::os_string_to_u8_vec(&value),
                    )
                })
                .collect(),
        )
    }
}

#[cfg(test)]
mod test {
    use super::{Env, RecordPair};

    #[test]
    fn parse_records_by_env_string() {
        let cases = vec![(
            b"a=b\0c=d\0",
            Env(vec![
                RecordPair(b"a".to_vec(), b"b".to_vec()),
                RecordPair(b"c".to_vec(), b"d".to_vec()),
            ]),
        )];

        for case in cases {
            let env_obj = Env::from(case.0.to_vec());
            assert_eq!(env_obj, case.1);
        }
    }
}