dangerous 0.10.0

Safely and explicitly parse untrusted / dangerous data
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

use crate::util::utf8::CharBytes;

///////////////////////////////////////////////////////////////////////////////
// u8

#[cfg(feature = "bytecount")]
#[inline(always)]
pub(crate) fn count_u8(needle: u8, haystack: &[u8]) -> usize {
    bytecount::count(haystack, needle)
}

#[cfg(not(feature = "bytecount"))]
pub(crate) fn count_u8(needle: u8, haystack: &[u8]) -> usize {
    haystack.iter().copied().filter(|b| *b == needle).count()
}

#[cfg(feature = "memchr")]
#[inline(always)]
pub(crate) fn find_u8_match(needle: u8, haystack: &[u8]) -> Option<usize> {
    memchr::memchr(needle, haystack)
}

#[cfg(not(feature = "memchr"))]
pub(crate) fn find_u8_match(needle: u8, haystack: &[u8]) -> Option<usize> {
    haystack.iter().copied().position(|b| b == needle)
}

// FIXME: impl SIMD variant
pub(crate) fn find_u8_reject(needle: u8, haystack: &[u8]) -> Option<usize> {
    haystack.iter().copied().position(|b| b != needle)
}

///////////////////////////////////////////////////////////////////////////////
// char

#[cfg(feature = "bytecount")]
#[inline(always)]
pub(crate) fn num_chars(s: &str) -> usize {
    bytecount::num_chars(s.as_bytes())
}

#[cfg(not(feature = "bytecount"))]
#[inline(always)]
pub(crate) fn num_chars(s: &str) -> usize {
    s.chars().count()
}

#[inline(always)]
pub(crate) fn find_char_match(needle: char, haystack: &[u8]) -> Option<usize> {
    let needle = CharBytes::from(needle);
    find_slice_match(needle.as_bytes(), haystack)
}

#[inline(always)]
pub(crate) fn find_char_reject(needle: char, haystack: &[u8]) -> Option<usize> {
    let needle = CharBytes::from(needle);
    find_slice_reject(needle.as_bytes(), haystack)
}

///////////////////////////////////////////////////////////////////////////////
// slice

#[cfg(feature = "memchr")]
pub(crate) fn find_slice_match(needle: &[u8], haystack: &[u8]) -> Option<usize> {
    if haystack.is_empty() || needle.is_empty() {
        return None;
    }
    match needle.len() {
        1 => memchr::memchr(needle[0], haystack),
        _ => memchr::memmem::find(haystack, needle),
    }
}

#[cfg(not(feature = "memchr"))]
pub(crate) fn find_slice_match(needle: &[u8], haystack: &[u8]) -> Option<usize> {
    if haystack.is_empty() || needle.is_empty() {
        return None;
    }
    haystack
        .windows(needle.len())
        .enumerate()
        .find_map(|(i, w)| if w == needle { Some(i) } else { None })
}

// FIXME: impl SIMD variant
pub(crate) fn find_slice_reject(needle: &[u8], haystack: &[u8]) -> Option<usize> {
    if haystack.is_empty() || needle.is_empty() || haystack.len() < needle.len() {
        return Some(0);
    }
    haystack
        .chunks(needle.len())
        .enumerate()
        .find_map(|(i, w)| {
            if w == needle {
                None
            } else {
                Some(i * needle.len())
            }
        })
}