ethox 0.0.2

A standalone network stack for user-space networking and unikernels
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

use core::ops;
use core::slice;

use crate::alloc;

/// A list of mutable objects.
#[derive(Debug, PartialEq, Eq, PartialOrd, Ord)]
pub enum Slice<'a, T: 'a> {
    /// A single inline instance.
    ///
    /// Great when a static lifetime is required but no dynamic allocation should take place. It
    /// should be obvious that the slice managed by this has length one.
    One(T),

    /// An allocated list of objects.
    Many(alloc::vec::Vec<T>),

    /// A list of objects living in borrowed memory.
    ///
    /// Best used when allocation is to be avoided at all costs but a dynamic length is required.
    Borrowed(&'a mut [T]),
}

impl<'a, T: 'a> Slice<'a, T> {
    /// Create an empty Slice, borrowing an empty slice.
    pub fn empty() -> Self {
        Slice::Borrowed(Default::default())
    }

    /// Construct a slice directly containing a single value.
    pub fn one_default() -> Self where T: Default {
        Slice::One(T::default())
    }

    /// Returns a reference to the contained data as a slice.
    pub fn as_slice(&self) -> &[T] {
        match self {
            Slice::One(t) => slice::from_ref(t),
            Slice::Many(vec) => vec.as_slice(),
            Slice::Borrowed(slice) => slice,
        }
    }

    /// Returns a reference to the contained data as a mutable slice.
    pub fn as_mut_slice(&mut self) -> &mut [T] {
        match self {
            Slice::One(t) => slice::from_mut(t),
            Slice::Many(vec) => vec.as_mut_slice(),
            Slice::Borrowed(slice) => slice,
        }
    }
}

impl<T> From<T> for Slice<'_, T> {
    fn from(t: T) -> Self {
        Slice::One(t)
    }
}

impl<T> From<Option<T>> for Slice<'_, T> {
    fn from(t: Option<T>) -> Self {
        match t {
            None => Slice::Borrowed(<&mut [T]>::default()),
            Some(t) => Slice::One(t),
        }
    }
}

impl<T> From<alloc::vec::Vec<T>> for Slice<'_, T> {
    fn from(t: alloc::vec::Vec<T>) -> Self {
        Slice::Many(t)
    }
}

impl<'a, T> From<&'a mut [T]> for Slice<'a, T> {
    fn from(t: &'a mut [T]) -> Self {
        Slice::Borrowed(t)
    }
}

impl<T> ops::Deref for Slice<'_, T> {
    type Target = [T];

    fn deref(&self) -> &[T] {
        self.as_slice()
    }
}

impl<T> ops::DerefMut for Slice<'_, T> {
    fn deref_mut(&mut self) -> &mut [T] {
        self.as_mut_slice()
    }
}