brotli/enc/
input_pair.rs

1use super::super::alloc::SliceWrapper;
2use super::super::alloc::SliceWrapperMut;
3use super::interface::Freezable;
4use core::cmp::min;
5#[derive(Copy, Clone, Default, Debug)]
6pub struct InputReference<'a> {
7    pub data: &'a [u8],
8    pub orig_offset: usize, // offset into the original slice of data
9}
10impl<'a> SliceWrapper<u8> for InputReference<'a> {
11    fn slice(&self) -> &[u8] {
12        self.data
13    }
14}
15
16impl<'a> Freezable for InputReference<'a> {
17    fn freeze(&self) -> super::interface::SliceOffset {
18        debug_assert!(self.data.len() <= 0xffff_ffff);
19        super::interface::SliceOffset(self.orig_offset, self.data.len() as u32)
20    }
21}
22
23#[derive(Default)]
24pub struct InputReferenceMut<'a> {
25    pub data: &'a mut [u8],
26    pub orig_offset: usize, // offset into the original slice of data
27}
28
29impl<'a> SliceWrapper<u8> for InputReferenceMut<'a> {
30    fn slice(&self) -> &[u8] {
31        self.data
32    }
33}
34impl<'a> SliceWrapperMut<u8> for InputReferenceMut<'a> {
35    fn slice_mut(&mut self) -> &mut [u8] {
36        self.data
37    }
38}
39
40impl<'a> From<InputReferenceMut<'a>> for InputReference<'a> {
41    fn from(val: InputReferenceMut<'a>) -> InputReference<'a> {
42        InputReference {
43            data: val.data,
44            orig_offset: val.orig_offset,
45        }
46    }
47}
48
49impl<'a> From<&'a InputReferenceMut<'a>> for InputReference<'a> {
50    fn from(val: &'a InputReferenceMut<'a>) -> InputReference<'a> {
51        InputReference {
52            data: val.data,
53            orig_offset: val.orig_offset,
54        }
55    }
56}
57
58#[derive(Clone, Debug, Copy)]
59pub struct InputPair<'a>(pub InputReference<'a>, pub InputReference<'a>);
60
61impl<'a> PartialEq for InputPair<'a> {
62    fn eq(&self, other: &InputPair<'_>) -> bool {
63        if self.0.len() + self.1.len() != other.0.len() + other.1.len() {
64            return false;
65        }
66        for (a_iter, b_iter) in self
67            .0
68            .data
69            .iter()
70            .chain(self.1.data.iter())
71            .zip(other.0.data.iter().chain(other.1.data.iter()))
72        {
73            if *a_iter != *b_iter {
74                return false;
75            }
76        }
77        true
78    }
79}
80impl<'a> core::ops::Index<usize> for InputPair<'a> {
81    type Output = u8;
82    fn index(&self, index: usize) -> &u8 {
83        if index >= self.0.len() {
84            &self.1.data[index - self.0.len()]
85        } else {
86            &self.0.data[index]
87        }
88    }
89}
90impl<'a> core::fmt::LowerHex for InputPair<'a> {
91    fn fmt(&self, fmtr: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
92        for item in self.0.data {
93            fmtr.write_fmt(format_args!("{:02x}", item))?
94        }
95        for item in self.1.data {
96            fmtr.write_fmt(format_args!("{:02x}", item))?
97        }
98        Ok(())
99    }
100}
101
102impl<'a> InputPair<'a> {
103    pub fn split_at(&self, loc: usize) -> (InputPair<'a>, InputPair<'a>) {
104        if loc >= self.0.len() {
105            let offset_from_self_1 = loc - self.0.len();
106            let (first, second) = self.1.data.split_at(min(offset_from_self_1, self.1.len()));
107            return (
108                InputPair::<'a>(
109                    self.0,
110                    InputReference::<'a> {
111                        data: first,
112                        orig_offset: self.1.orig_offset,
113                    },
114                ),
115                InputPair::<'a>(
116                    InputReference::<'a>::default(),
117                    InputReference::<'a> {
118                        data: second,
119                        orig_offset: offset_from_self_1 + self.1.orig_offset,
120                    },
121                ),
122            );
123        }
124        let (first, second) = self.0.data.split_at(min(loc, self.0.len()));
125        (
126            InputPair::<'a>(
127                InputReference::<'a> {
128                    data: first,
129                    orig_offset: self.0.orig_offset,
130                },
131                InputReference::<'a>::default(),
132            ),
133            InputPair::<'a>(
134                InputReference::<'a> {
135                    data: second,
136                    orig_offset: self.0.orig_offset + loc,
137                },
138                self.1,
139            ),
140        )
141    }
142    pub fn len(&self) -> usize {
143        self.0.len() + self.1.len()
144    }
145}
brotli/enc/input_pair.rs

brotli/enc/
input_pair.rs
