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

use std::fmt;
use std::ptr::NonNull;

/// Convenience type for holding value of `*mut T`
/// Mostly just a projection of `NonNull<T>` functionality
#[derive(Debug, Eq, Hash, PartialOrd, PartialEq)]
pub struct Ptr<T> {
    inner: NonNull<T>
}

impl<T: Copy> Copy for Ptr<T> {}
impl<T: Clone> Clone for Ptr<T> {
    fn clone(&self) -> Self {
        Ptr {inner: self.inner.clone()}
    }
}

impl<T> Ptr<T> {
    /// Wraps a valid `NonNull<T>` 
    pub fn new(p: NonNull<T>) -> Ptr<T> {
        Ptr { inner: p }
    }

    /// Checks a `*mut T` for null and wraps it up for easier handling.
    pub fn with_checked(p: *mut T) -> Option<Ptr<T>> {
        match NonNull::new(p) {
            Some(p) => Some(Ptr::new(p)),
            None => None
        }
    }

    /// Get inner ptr
    pub fn as_ptr(&self) -> *mut T {
        self.inner.as_ptr()
    }

    /// Get inner reference
    pub unsafe fn as_ref(&self) -> &T {
        self.inner.as_ref()
    }

    /// Cast a `Ptr<T>` to `Ptr<U>`
    pub fn cast<U>(self) -> Ptr<U> {
        Ptr::new(self.inner.cast())
    }
}

impl<T> fmt::Pointer for Ptr<T> {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        write!(f, "{:p}", self.inner)
    }
}

impl<T> From<NonNull<T>> for Ptr<T> {
    fn from(nn: NonNull<T>) -> Self {
        Ptr::new(nn)
    }
}

impl<T> Into<NonNull<T>> for Ptr<T> {
    fn into(self) -> NonNull<T> {
        self.inner
    }
}

impl<T> AsRef<T> for Ptr<T> {
    fn as_ref(&self) -> &T {
        unsafe {self.as_ref()}
    }
}