lsofrs 4.11.1

Modern, high-performance lsof implementation in Rust
Documentation 
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

//! String helpers for display — avoid panicking on UTF-8 boundaries.

/// Truncate `s` to at most `max_bytes` UTF-8 bytes without splitting a scalar value.
#[must_use]
pub fn truncate_max_bytes(s: &str, max_bytes: usize) -> &str {
    if s.len() <= max_bytes {
        s
    } else {
        let end = s.floor_char_boundary(max_bytes);
        &s[..end]
    }
}

/// Encode `data` as standard base64 (RFC 4648, with `=` padding).
#[must_use]
pub fn base64_encode(data: &[u8]) -> String {
    const ALPHABET: &[u8; 64] = b"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
    let mut out = String::with_capacity(data.len().div_ceil(3) * 4);
    for chunk in data.chunks(3) {
        let b0 = u32::from(chunk[0]);
        let b1 = chunk.get(1).map_or(0, |b| u32::from(*b));
        let b2 = chunk.get(2).map_or(0, |b| u32::from(*b));
        let n = (b0 << 16) | (b1 << 8) | b2;
        out.push(ALPHABET[(n >> 18) as usize & 0x3f] as char);
        out.push(ALPHABET[(n >> 12) as usize & 0x3f] as char);
        out.push(if chunk.len() > 1 {
            ALPHABET[(n >> 6) as usize & 0x3f] as char
        } else {
            '='
        });
        out.push(if chunk.len() > 2 {
            ALPHABET[n as usize & 0x3f] as char
        } else {
            '='
        });
    }
    out
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn truncate_ascii_short_unchanged() {
        assert_eq!(truncate_max_bytes("hello", 8), "hello");
    }

    #[test]
    fn truncate_ascii_long() {
        assert_eq!(truncate_max_bytes("helloworld", 5), "hello");
    }

    #[test]
    fn truncate_cjk_no_panic_and_char_aligned() {
        let s = "田田田";
        assert_eq!(s.len(), 9);
        let t = truncate_max_bytes(s, 8);
        assert!(t.len() <= 8);
        assert_eq!(t, "田田");
    }

    #[test]
    fn truncate_empty_max_zero() {
        assert_eq!(truncate_max_bytes("x", 0), "");
    }

    #[test]
    fn truncate_emoji_four_byte_char_split_mid_glyph() {
        let s = "a🎉b";
        assert_eq!(s.len(), 6);
        let t = truncate_max_bytes(s, 2);
        assert_eq!(t, "a");
        let t2 = truncate_max_bytes(s, 5);
        assert_eq!(t2, "a🎉");
    }

    #[test]
    fn truncate_max_bytes_equals_full_len_unchanged() {
        let s = "exact";
        assert_eq!(truncate_max_bytes(s, s.len()), s);
    }

    #[test]
    fn truncate_grapheme_cluster_not_special_cased_still_safe() {
        // "e" + combining acute — two Unicode scalars; truncation is scalar-safe not grapheme-safe
        let s = "e\u{0301}";
        assert_eq!(s.len(), 3);
        assert_eq!(truncate_max_bytes(s, 1), "e");
    }

    #[test]
    fn truncate_utf8_max_one_past_ascii_prefix_keeps_ascii_only() {
        assert_eq!(truncate_max_bytes("ab田", 3), "ab");
    }

    #[test]
    fn truncate_empty_string_any_limit() {
        assert_eq!(truncate_max_bytes("", 0), "");
        assert_eq!(truncate_max_bytes("", 100), "");
    }
}