hexdino 0.1.0

A hex editor with vim like keybindings written 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
137
138
139
140
141
142

// To search for nibbles in a byte array.
// Requires two nibbles per byte.
// All values above 0x0F will be used as wildcard.
// Example: Use x or X as wildcard for a nibble.

pub trait FindOptSubset {
    fn find_subset(&self, subset: &[u8]) -> Option<usize>;
}

impl FindOptSubset for Vec<u8> {
    fn find_subset(&self, subset: &[u8]) -> Option<usize> {
        if subset.len() > 2 * self.len() {
            return None;
        }
        if subset.len() % 2 != 0 {
            // Must be dividable by two
            return None;
        }
        // Search in a for b
        for a in 0..self.len() - subset.len() / 2 + 1 {
            for b in 0..subset.len() / 2 {
                // if b is not a, skip searching at that position in a
                // Logic: both match, ...
                // or first nibble matches when second nibble is wildcard,
                // or second nibble matches when first nibble is wildcard.
                // or two wildcards at that position.
                if !(
                    ((subset[2*b  ] == self[a + b]>>4) && (subset[2*b+1] == self[a + b]%16)) ||
                    ((subset[2*b  ] == self[a + b]>>4) && (subset[2*b+1] >= 0x10)) ||
                    ((subset[2*b+1] == self[a + b]%16) && (subset[2*b  ] >= 0x10)) ||
                    ((subset[2*b+1] >= 0x10) && (subset[2*b  ] >= 0x10))
                   ) {
                    break; // element does not match
                }
                // when all elements of b match in a, return position of a
                if b == subset.len() / 2 - 1 {
                    return Some(a);
                }
            }
        }
        None
    }
}

#[test]
fn find_subset_partial_at_start() {
    let buf = vec![0x01, 0x02, 0x03, 0x04, 0x05];
    let sub = vec![0x00, 0x01];
    assert_eq!(buf.find_subset(&sub), Some(0));
}
#[test]
fn find_subset_partial_at_middle() {
    let buf = vec![0x01, 0x02, 0x03, 0x04, 0x05];
    let sub = vec![0x00, 0x03, 0x00, 0x04];
    assert_eq!(buf.find_subset(&sub), Some(2));
}
#[test]
fn find_subset_partial_at_end() {
    let buf = vec![0x01, 0x02, 0x03, 0x04, 0x05];
    let sub = vec![0x00, 0x04, 0x00, 0x05];
    assert_eq!(buf.find_subset(&sub), Some(3));
}
#[test]
fn find_subset_partial_after_end() {
    let buf = vec![0x01, 0x02, 0x03, 0x04, 0x05];
    let sub = vec![0x00, 0x05, 0x00, 0x06];
    assert_eq!(buf.find_subset(&sub), None);
}
#[test]
fn find_subset_partial_before_start() {
    let buf = vec![0x01, 0x02, 0x03, 0x04, 0x05];
    let sub = vec![0x00, 0x00, 0x00, 0x01];
    assert_eq!(buf.find_subset(&sub), None);
}
#[test]
fn find_subset_short() {
    let buf = vec![0x01, 0x02, 0x03, 0x04, 0x05];
    let sub = vec![0x00, 0x02];
    assert_eq!(buf.find_subset(&sub), Some(1));
}
#[test]
fn find_subset_too_long() {
    let buf = vec![0x01, 0x02, 0x03, 0x04, 0x05];
    let sub = vec![
        0x00, 0x01, 0x00, 0x02, 0x00, 0x03, 0x00, 0x04, 0x00, 0x05, 0x00, 0x06,
    ];
    assert_eq!(buf.find_subset(&sub), None);
}
#[test]
fn find_subset_full() {
    let buf = vec![0x01, 0x02, 0x03, 0x04, 0x05];
    let sub = vec![0x00, 0x01, 0x00, 0x02, 0x00, 0x03, 0x00, 0x04, 0x00, 0x05];
    assert_eq!(buf.find_subset(&sub), Some(0));
}
#[test]
fn find_subset_swapped() {
    let buf = vec![0x01, 0x02, 0x03, 0x04, 0x05];
    let sub = vec![0x00, 0x05, 0x00, 0x04, 0x00, 0x03, 0x00, 0x02, 0x00, 0x01];
    assert_eq!(buf.find_subset(&sub), None);
}
#[test]
fn find_subset_higher_than_9() {
    let buf = vec![0x0A, 0x0C, 0x0D, 0x0E, 0x0F];
    let sub = vec![0x00, 0x0C, 0x00, 0x0D, 0x00, 0x0E];
    assert_eq!(buf.find_subset(&sub), Some(1));
}
#[test]
fn find_subset_higher_than_f() {
    let buf = vec![0x0A, 0x3C, 0x1D, 0xEE, 0x0F];
    let sub = vec![0x03, 0x0C, 0x01, 0x0D, 0x0E, 0x0E];
    assert_eq!(buf.find_subset(&sub), Some(1));
}
#[test]
fn find_with_single_wildcard_0x10() {
    let buf = vec![0x0A, 0x3C, 0x1D, 0xEE, 0x0F];
    let sub = vec![0x03, 0x0C, 0x01, 0x10, 0x0E, 0x0E];
    assert_eq!(buf.find_subset(&sub), Some(1));
}
#[test]
fn find_with_wildcard_0xf0() {
    let buf = vec![0x0A, 0x3C, 0x1D, 0xEE, 0x0F];
    let sub = vec![0x03, 0x0C, 0xF0, 0xF0, 0x0E, 0x0E];
    assert_eq!(buf.find_subset(&sub), Some(1));
}
#[test]
fn find_with_wildcard_xX() {
    let buf = vec![0x0A, 0x3C, 0x1D, 0xEE, 0x0F];
    let sub = vec![0x03, 0x0C, 'x' as u8, 'X' as u8, 0x0E, 0x0E];
    assert_eq!(buf.find_subset(&sub), Some(1));
}
#[test]
fn find_with_wildcards() {
    let buf = vec![0x0A, 0x3C, 0x1D, 0xEE, 0x0F];
    let sub = vec![0x10, 0x10, 0x10, 0x10, 0x10, 0x10];
    assert_eq!(buf.find_subset(&sub), Some(0));
}
#[test]
fn find_shifted() {
    let buf = vec![0x0A, 0x3C, 0x1D, 0xEE, 0x0F];
    let sub = vec![0x0A, 0x03];
    assert_eq!(buf.find_subset(&sub), None);
}