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
143
144
145
146
147
148
149
150
151
152
|
//! Common handling for types backed by byte slices with enforcement of a
//! library-level length limitation i.e. `Length::max()`.
use crate::{
DecodeValue, DerOrd, EncodeValue, Error, Header, Length, Reader, Result, StrRef, Writer,
};
use core::cmp::Ordering;
#[cfg(feature = "alloc")]
use crate::StrOwned;
/// Byte slice newtype which respects the `Length::max()` limit.
#[derive(Copy, Clone, Debug, Eq, PartialEq, PartialOrd, Ord)]
pub(crate) struct BytesRef<'a> {
/// Precomputed `Length` (avoids possible panicking conversions)
pub length: Length,
/// Inner value
pub inner: &'a [u8],
}
impl<'a> BytesRef<'a> {
/// Constant value representing an empty byte slice.
pub const EMPTY: Self = Self {
length: Length::ZERO,
inner: &[],
};
/// Create a new [`BytesRef`], ensuring that the provided `slice` value
/// is shorter than `Length::max()`.
pub fn new(slice: &'a [u8]) -> Result<Self> {
Ok(Self {
length: Length::try_from(slice.len())?,
inner: slice,
})
}
/// Borrow the inner byte slice
pub fn as_slice(&self) -> &'a [u8] {
self.inner
}
/// Get the [`Length`] of this [`BytesRef`]
pub fn len(self) -> Length {
self.length
}
/// Is this [`BytesRef`] empty?
pub fn is_empty(self) -> bool {
self.len() == Length::ZERO
}
}
impl AsRef<[u8]> for BytesRef<'_> {
fn as_ref(&self) -> &[u8] {
self.as_slice()
}
}
impl<'a> DecodeValue<'a> for BytesRef<'a> {
fn decode_value<R: Reader<'a>>(reader: &mut R, header: Header) -> Result<Self> {
reader.read_slice(header.length).and_then(Self::new)
}
}
impl EncodeValue for BytesRef<'_> {
fn value_len(&self) -> Result<Length> {
Ok(self.length)
}
fn encode_value(&self, writer: &mut impl Writer) -> Result<()> {
writer.write(self.as_ref())
}
}
impl Default for BytesRef<'_> {
fn default() -> Self {
Self {
length: Length::ZERO,
inner: &[],
}
}
}
impl DerOrd for BytesRef<'_> {
fn der_cmp(&self, other: &Self) -> Result<Ordering> {
Ok(self.as_slice().cmp(other.as_slice()))
}
}
impl<'a> From<StrRef<'a>> for BytesRef<'a> {
fn from(s: StrRef<'a>) -> BytesRef<'a> {
let bytes = s.as_bytes();
debug_assert_eq!(bytes.len(), usize::try_from(s.length).expect("overflow"));
BytesRef {
inner: bytes,
length: s.length,
}
}
}
#[cfg(feature = "alloc")]
impl<'a> From<&'a StrOwned> for BytesRef<'a> {
fn from(s: &'a StrOwned) -> BytesRef<'a> {
let bytes = s.as_bytes();
debug_assert_eq!(bytes.len(), usize::try_from(s.length).expect("overflow"));
BytesRef {
inner: bytes,
length: s.length,
}
}
}
impl<'a> TryFrom<&'a [u8]> for BytesRef<'a> {
type Error = Error;
fn try_from(slice: &'a [u8]) -> Result<Self> {
Self::new(slice)
}
}
// Implement by hand because the derive would create invalid values.
// Make sure the length and the inner.len matches.
#[cfg(feature = "arbitrary")]
impl<'a> arbitrary::Arbitrary<'a> for BytesRef<'a> {
fn arbitrary(u: &mut arbitrary::Unstructured<'a>) -> arbitrary::Result<Self> {
let length = u.arbitrary()?;
Ok(Self {
length,
inner: u.bytes(u32::from(length) as usize)?,
})
}
fn size_hint(depth: usize) -> (usize, Option<usize>) {
arbitrary::size_hint::and(Length::size_hint(depth), (0, None))
}
}
#[cfg(feature = "alloc")]
mod allocating {
use super::BytesRef;
use crate::{referenced::RefToOwned, BytesOwned};
impl<'a> RefToOwned<'a> for BytesRef<'a> {
type Owned = BytesOwned;
fn ref_to_owned(&self) -> Self::Owned {
BytesOwned::from(*self)
}
}
}
|
