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use alloc::boxed::Box;
use core::marker::PhantomData;
use core::ptr::NonNull;
#[repr(transparent)]
pub struct Own<T>
where
T: ?Sized,
{
pub ptr: NonNull<T>,
}
unsafe impl<T> Send for Own<T> where T: ?Sized {}
unsafe impl<T> Sync for Own<T> where T: ?Sized {}
impl<T> Copy for Own<T> where T: ?Sized {}
impl<T> Clone for Own<T>
where
T: ?Sized,
{
fn clone(&self) -> Self {
*self
}
}
impl<T> Own<T>
where
T: ?Sized,
{
pub fn new(ptr: Box<T>) -> Self {
Own {
ptr: unsafe { NonNull::new_unchecked(Box::into_raw(ptr)) },
}
}
pub fn cast<U: CastTo>(self) -> Own<U::Target> {
Own {
ptr: self.ptr.cast(),
}
}
pub unsafe fn boxed(self) -> Box<T> {
Box::from_raw(self.ptr.as_ptr())
}
pub fn by_ref(&self) -> Ref<T> {
Ref {
ptr: self.ptr,
lifetime: PhantomData,
}
}
pub fn by_mut(&mut self) -> Mut<T> {
Mut {
ptr: self.ptr,
lifetime: PhantomData,
}
}
}
#[repr(transparent)]
pub struct Ref<'a, T>
where
T: ?Sized,
{
pub ptr: NonNull<T>,
lifetime: PhantomData<&'a T>,
}
impl<'a, T> Copy for Ref<'a, T> where T: ?Sized {}
impl<'a, T> Clone for Ref<'a, T>
where
T: ?Sized,
{
fn clone(&self) -> Self {
*self
}
}
impl<'a, T> Ref<'a, T>
where
T: ?Sized,
{
pub fn new(ptr: &'a T) -> Self {
Ref {
ptr: NonNull::from(ptr),
lifetime: PhantomData,
}
}
#[cfg(not(anyhow_no_ptr_addr_of))]
pub fn from_raw(ptr: NonNull<T>) -> Self {
Ref {
ptr,
lifetime: PhantomData,
}
}
pub fn cast<U: CastTo>(self) -> Ref<'a, U::Target> {
Ref {
ptr: self.ptr.cast(),
lifetime: PhantomData,
}
}
#[cfg(not(anyhow_no_ptr_addr_of))]
pub fn by_mut(self) -> Mut<'a, T> {
Mut {
ptr: self.ptr,
lifetime: PhantomData,
}
}
#[cfg(not(anyhow_no_ptr_addr_of))]
pub fn as_ptr(self) -> *const T {
self.ptr.as_ptr() as *const T
}
pub unsafe fn deref(self) -> &'a T {
&*self.ptr.as_ptr()
}
}
#[repr(transparent)]
pub struct Mut<'a, T>
where
T: ?Sized,
{
pub ptr: NonNull<T>,
lifetime: PhantomData<&'a mut T>,
}
impl<'a, T> Copy for Mut<'a, T> where T: ?Sized {}
impl<'a, T> Clone for Mut<'a, T>
where
T: ?Sized,
{
fn clone(&self) -> Self {
*self
}
}
impl<'a, T> Mut<'a, T>
where
T: ?Sized,
{
#[cfg(anyhow_no_ptr_addr_of)]
pub fn new(ptr: &'a mut T) -> Self {
Mut {
ptr: NonNull::from(ptr),
lifetime: PhantomData,
}
}
pub fn cast<U: CastTo>(self) -> Mut<'a, U::Target> {
Mut {
ptr: self.ptr.cast(),
lifetime: PhantomData,
}
}
#[cfg(not(anyhow_no_ptr_addr_of))]
pub fn by_ref(self) -> Ref<'a, T> {
Ref {
ptr: self.ptr,
lifetime: PhantomData,
}
}
pub fn extend<'b>(self) -> Mut<'b, T> {
Mut {
ptr: self.ptr,
lifetime: PhantomData,
}
}
pub unsafe fn deref_mut(self) -> &'a mut T {
&mut *self.ptr.as_ptr()
}
}
impl<'a, T> Mut<'a, T> {
pub unsafe fn read(self) -> T {
self.ptr.as_ptr().read()
}
}
// Force turbofish on all calls of `.cast::<U>()`.
pub trait CastTo {
type Target;
}
impl<T> CastTo for T {
type Target = T;
}