/rust/registry/src/index.crates.io-6f17d22bba15001f/futures-task-0.3.31/src/future_obj.rs

Source (jump to first uncovered line)
use core::{
    fmt,
    future::Future,
    marker::PhantomData,
    mem,
    pin::Pin,
    task::{Context, Poll},
};

/// A custom trait object for polling futures, roughly akin to
/// `Box<dyn Future<Output = T> + 'a>`.
///
/// This custom trait object was introduced as currently it is not possible to
/// take `dyn Trait` by value and `Box<dyn Trait>` is not available in no_std
/// contexts.
pub struct LocalFutureObj<'a, T> {
    future: *mut (dyn Future<Output = T> + 'static),
    drop_fn: unsafe fn(*mut (dyn Future<Output = T> + 'static)),
    _marker: PhantomData<&'a ()>,
}

// As LocalFutureObj only holds pointers, even if we move it, the pointed to values won't move,
// so this is safe as long as we don't provide any way for a user to directly access the pointers
// and move their values.
impl<T> Unpin for LocalFutureObj<'_, T> {}

#[allow(single_use_lifetimes)]
#[allow(clippy::transmute_ptr_to_ptr)]
unsafe fn remove_future_lifetime<'a, T>(
    ptr: *mut (dyn Future<Output = T> + 'a),
) -> *mut (dyn Future<Output = T> + 'static) {
    unsafe { mem::transmute(ptr) }
}

#[allow(single_use_lifetimes)]
unsafe fn remove_drop_lifetime<'a, T>(
    ptr: unsafe fn(*mut (dyn Future<Output = T> + 'a)),
) -> unsafe fn(*mut (dyn Future<Output = T> + 'static)) {
    unsafe { mem::transmute(ptr) }
}

impl<'a, T> LocalFutureObj<'a, T> {
    /// Create a `LocalFutureObj` from a custom trait object representation.
    #[inline]
    pub fn new<F: UnsafeFutureObj<'a, T> + 'a>(f: F) -> Self {
        Self {
            future: unsafe { remove_future_lifetime(f.into_raw()) },
            drop_fn: unsafe { remove_drop_lifetime(F::drop) },
            _marker: PhantomData,
        }
    }

    /// Converts the `LocalFutureObj` into a `FutureObj`.
    ///
    /// # Safety
    ///
    /// To make this operation safe one has to ensure that the `UnsafeFutureObj`
    /// instance from which this `LocalFutureObj` was created actually
    /// implements `Send`.
    #[inline]
    pub unsafe fn into_future_obj(self) -> FutureObj<'a, T> {
        FutureObj(self)
    }
}

impl<T> fmt::Debug for LocalFutureObj<'_, T> {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.debug_struct("LocalFutureObj").finish()
    }
}

impl<'a, T> From<FutureObj<'a, T>> for LocalFutureObj<'a, T> {
    #[inline]
    fn from(f: FutureObj<'a, T>) -> Self {
        f.0
    }
}

impl<T> Future for LocalFutureObj<'_, T> {
    type Output = T;

    #[inline]
    fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<T> {
        unsafe { Pin::new_unchecked(&mut *self.future).poll(cx) }
    }
}

impl<T> Drop for LocalFutureObj<'_, T> {
    fn drop(&mut self) {
        unsafe { (self.drop_fn)(self.future) }
    }
}

/// A custom trait object for polling futures, roughly akin to
/// `Box<dyn Future<Output = T> + Send + 'a>`.
///
/// This custom trait object was introduced as currently it is not possible to
/// take `dyn Trait` by value and `Box<dyn Trait>` is not available in no_std
/// contexts.
///
/// You should generally not need to use this type outside of `no_std` or when
/// implementing `Spawn`, consider using `BoxFuture` instead.
pub struct FutureObj<'a, T>(LocalFutureObj<'a, T>);

impl<T> Unpin for FutureObj<'_, T> {}
unsafe impl<T> Send for FutureObj<'_, T> {}

impl<'a, T> FutureObj<'a, T> {
    /// Create a `FutureObj` from a custom trait object representation.
    #[inline]
    pub fn new<F: UnsafeFutureObj<'a, T> + Send>(f: F) -> Self {
        Self(LocalFutureObj::new(f))
    }
}

impl<T> fmt::Debug for FutureObj<'_, T> {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.debug_struct("FutureObj").finish()
    }
}

impl<T> Future for FutureObj<'_, T> {
    type Output = T;

    #[inline]
    fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<T> {
        Pin::new(&mut self.0).poll(cx)
    }
}

/// A custom implementation of a future trait object for `FutureObj`, providing
/// a vtable with drop support.
///
/// This custom representation is typically used only in `no_std` contexts,
/// where the default `Box`-based implementation is not available.
///
/// # Safety
///
/// See the safety notes on individual methods for what guarantees an
/// implementor must provide.
pub unsafe trait UnsafeFutureObj<'a, T>: 'a {
    /// Convert an owned instance into a (conceptually owned) fat pointer.
    ///
    /// # Safety
    ///
    /// ## Implementor
    ///
    /// The trait implementor must guarantee that it is safe to convert the
    /// provided `*mut (dyn Future<Output = T> + 'a)` into a `Pin<&mut (dyn
    /// Future<Output = T> + 'a)>` and call methods on it, non-reentrantly,
    /// until `UnsafeFutureObj::drop` is called with it.
    #[allow(clippy::unnecessary_safety_doc)]
    fn into_raw(self) -> *mut (dyn Future<Output = T> + 'a);

    /// Drops the future represented by the given fat pointer.
    ///
    /// # Safety
    ///
    /// ## Implementor
    ///
    /// The trait implementor must guarantee that it is safe to call this
    /// function once per `into_raw` invocation.
    ///
    /// ## Caller
    ///
    /// The caller must ensure:
    ///
    ///  * the pointer passed was obtained from an `into_raw` invocation from
    ///    this same trait object
    ///  * the pointer is not currently in use as a `Pin<&mut (dyn Future<Output
    ///    = T> + 'a)>`
    ///  * the pointer must not be used again after this function is called
    unsafe fn drop(ptr: *mut (dyn Future<Output = T> + 'a));
}

unsafe impl<'a, T, F> UnsafeFutureObj<'a, T> for &'a mut F
where
    F: Future<Output = T> + Unpin + 'a,
{
    fn into_raw(self) -> *mut (dyn Future<Output = T> + 'a) {
        self as *mut dyn Future<Output = T>
    }

    unsafe fn drop(_ptr: *mut (dyn Future<Output = T> + 'a)) {}
}

unsafe impl<'a, T> UnsafeFutureObj<'a, T> for &'a mut (dyn Future<Output = T> + Unpin + 'a) {
    fn into_raw(self) -> *mut (dyn Future<Output = T> + 'a) {
        self as *mut dyn Future<Output = T>
    }

    unsafe fn drop(_ptr: *mut (dyn Future<Output = T> + 'a)) {}
}

unsafe impl<'a, T, F> UnsafeFutureObj<'a, T> for Pin<&'a mut F>
where
    F: Future<Output = T> + 'a,
{
    fn into_raw(self) -> *mut (dyn Future<Output = T> + 'a) {
        unsafe { self.get_unchecked_mut() as *mut dyn Future<Output = T> }
    }

    unsafe fn drop(_ptr: *mut (dyn Future<Output = T> + 'a)) {}
}

unsafe impl<'a, T> UnsafeFutureObj<'a, T> for Pin<&'a mut (dyn Future<Output = T> + 'a)> {
    fn into_raw(self) -> *mut (dyn Future<Output = T> + 'a) {
        unsafe { self.get_unchecked_mut() as *mut dyn Future<Output = T> }
    }

    unsafe fn drop(_ptr: *mut (dyn Future<Output = T> + 'a)) {}
}

#[cfg(feature = "alloc")]
mod if_alloc {
    use super::*;
    use alloc::boxed::Box;

    unsafe impl<'a, T, F> UnsafeFutureObj<'a, T> for Box<F>
    where
        F: Future<Output = T> + 'a,
    {
        fn into_raw(self) -> *mut (dyn Future<Output = T> + 'a) {
            Box::into_raw(self)
        }

        unsafe fn drop(ptr: *mut (dyn Future<Output = T> + 'a)) {
            drop(unsafe { Box::from_raw(ptr.cast::<F>()) })
        }
    }

    unsafe impl<'a, T: 'a> UnsafeFutureObj<'a, T> for Box<dyn Future<Output = T> + 'a> {
        fn into_raw(self) -> *mut (dyn Future<Output = T> + 'a) {
            Box::into_raw(self)
        }

        unsafe fn drop(ptr: *mut (dyn Future<Output = T> + 'a)) {
            drop(unsafe { Box::from_raw(ptr) })
        }
    }

    unsafe impl<'a, T: 'a> UnsafeFutureObj<'a, T> for Box<dyn Future<Output = T> + Send + 'a> {
        fn into_raw(self) -> *mut (dyn Future<Output = T> + 'a) {
            Box::into_raw(self)
        }

        unsafe fn drop(ptr: *mut (dyn Future<Output = T> + 'a)) {
            drop(unsafe { Box::from_raw(ptr) })
        }
    }

    unsafe impl<'a, T, F> UnsafeFutureObj<'a, T> for Pin<Box<F>>
    where
        F: Future<Output = T> + 'a,
    {
        fn into_raw(self) -> *mut (dyn Future<Output = T> + 'a) {
            let mut this = mem::ManuallyDrop::new(self);
            unsafe { this.as_mut().get_unchecked_mut() as *mut _ }
        }

        unsafe fn drop(ptr: *mut (dyn Future<Output = T> + 'a)) {
            drop(Pin::from(unsafe { Box::from_raw(ptr) }))
        }
    }

    unsafe impl<'a, T: 'a> UnsafeFutureObj<'a, T> for Pin<Box<dyn Future<Output = T> + 'a>> {
        fn into_raw(self) -> *mut (dyn Future<Output = T> + 'a) {
            let mut this = mem::ManuallyDrop::new(self);
            unsafe { this.as_mut().get_unchecked_mut() as *mut _ }
        }

        unsafe fn drop(ptr: *mut (dyn Future<Output = T> + 'a)) {
            drop(Pin::from(unsafe { Box::from_raw(ptr) }))
        }
    }

    unsafe impl<'a, T: 'a> UnsafeFutureObj<'a, T> for Pin<Box<dyn Future<Output = T> + Send + 'a>> {
        fn into_raw(self) -> *mut (dyn Future<Output = T> + 'a) {
            let mut this = mem::ManuallyDrop::new(self);
            unsafe { this.as_mut().get_unchecked_mut() as *mut _ }
        }

        unsafe fn drop(ptr: *mut (dyn Future<Output = T> + 'a)) {
            drop(Pin::from(unsafe { Box::from_raw(ptr) }))
        }
    }

    impl<'a, F: Future<Output = ()> + Send + 'a> From<Box<F>> for FutureObj<'a, ()> {
        fn from(boxed: Box<F>) -> Self {
            Self::new(boxed)
        }
    }

    impl<'a> From<Box<dyn Future<Output = ()> + Send + 'a>> for FutureObj<'a, ()> {
        fn from(boxed: Box<dyn Future<Output = ()> + Send + 'a>) -> Self {
            Self::new(boxed)
        }
    }

    impl<'a, F: Future<Output = ()> + Send + 'a> From<Pin<Box<F>>> for FutureObj<'a, ()> {
        fn from(boxed: Pin<Box<F>>) -> Self {
            Self::new(boxed)
        }
    }

    impl<'a> From<Pin<Box<dyn Future<Output = ()> + Send + 'a>>> for FutureObj<'a, ()> {
        fn from(boxed: Pin<Box<dyn Future<Output = ()> + Send + 'a>>) -> Self {
            Self::new(boxed)
        }
    }

    impl<'a, F: Future<Output = ()> + 'a> From<Box<F>> for LocalFutureObj<'a, ()> {
        fn from(boxed: Box<F>) -> Self {
            Self::new(boxed)
        }
    }

    impl<'a> From<Box<dyn Future<Output = ()> + 'a>> for LocalFutureObj<'a, ()> {
        fn from(boxed: Box<dyn Future<Output = ()> + 'a>) -> Self {
            Self::new(boxed)
        }
    }

    impl<'a, F: Future<Output = ()> + 'a> From<Pin<Box<F>>> for LocalFutureObj<'a, ()> {
        fn from(boxed: Pin<Box<F>>) -> Self {
            Self::new(boxed)
        }
    }

    impl<'a> From<Pin<Box<dyn Future<Output = ()> + 'a>>> for LocalFutureObj<'a, ()> {
        fn from(boxed: Pin<Box<dyn Future<Output = ()> + 'a>>) -> Self {
            Self::new(boxed)
        }
    }
}

Coverage Report

Created: 2025-07-23 06:46

Line	Count	Source (jump to first uncovered line)
1		use core::{
2		fmt,
3		future::Future,
4		marker::PhantomData,
5		mem,
6		pin::Pin,
7		task::{Context, Poll},
8		};
9
10		/// A custom trait object for polling futures, roughly akin to
11		/// `Box<dyn Future<Output = T> + 'a>`.
12		///
13		/// This custom trait object was introduced as currently it is not possible to
14		/// take `dyn Trait` by value and `Box<dyn Trait>` is not available in no_std
15		/// contexts.
16		pub struct LocalFutureObj<'a, T> {
17		future: *mut (dyn Future<Output = T> + 'static),
18		drop_fn: unsafe fn(*mut (dyn Future<Output = T> + 'static)),
19		_marker: PhantomData<&'a ()>,
20		}
21
22		// As LocalFutureObj only holds pointers, even if we move it, the pointed to values won't move,
23		// so this is safe as long as we don't provide any way for a user to directly access the pointers
24		// and move their values.
25		impl<T> Unpin for LocalFutureObj<'_, T> {}
26
27		#[allow(single_use_lifetimes)]
28		#[allow(clippy::transmute_ptr_to_ptr)]
29	0	unsafe fn remove_future_lifetime<'a, T>(
30	0	ptr: *mut (dyn Future<Output = T> + 'a),
31	0	) -> *mut (dyn Future<Output = T> + 'static) {
32	0	unsafe { mem::transmute(ptr) }
33	0	}
34
35		#[allow(single_use_lifetimes)]
36	0	unsafe fn remove_drop_lifetime<'a, T>(
37	0	ptr: unsafe fn(*mut (dyn Future<Output = T> + 'a)),
38	0	) -> unsafe fn(*mut (dyn Future<Output = T> + 'static)) {
39	0	unsafe { mem::transmute(ptr) }
40	0	}
41
42		impl<'a, T> LocalFutureObj<'a, T> {
43		/// Create a `LocalFutureObj` from a custom trait object representation.
44		#[inline]
45	0	pub fn new<F: UnsafeFutureObj<'a, T> + 'a>(f: F) -> Self {
46	0	Self {
47	0	future: unsafe { remove_future_lifetime(f.into_raw()) },
48	0	drop_fn: unsafe { remove_drop_lifetime(F::drop) },
49	0	_marker: PhantomData,
50	0	}
51	0	} Unexecuted instantiation: <futures_task::future_obj::LocalFutureObj<()>>::new::<alloc::boxed::Box<dyn core::future::future::Future<Output = ()>>> Unexecuted instantiation: <futures_task::future_obj::LocalFutureObj<()>>::new::<alloc::boxed::Box<dyn core::future::future::Future<Output = ()> + core::marker::Send>> Unexecuted instantiation: <futures_task::future_obj::LocalFutureObj<()>>::new::<core::pin::Pin<alloc::boxed::Box<dyn core::future::future::Future<Output = ()>>>> Unexecuted instantiation: <futures_task::future_obj::LocalFutureObj<()>>::new::<core::pin::Pin<alloc::boxed::Box<dyn core::future::future::Future<Output = ()> + core::marker::Send>>>
52
53		/// Converts the `LocalFutureObj` into a `FutureObj`.
54		///
55		/// # Safety
56		///
57		/// To make this operation safe one has to ensure that the `UnsafeFutureObj`
58		/// instance from which this `LocalFutureObj` was created actually
59		/// implements `Send`.
60		#[inline]
61	0	pub unsafe fn into_future_obj(self) -> FutureObj<'a, T> {
62	0	FutureObj(self)
63	0	}
64		}
65
66		impl<T> fmt::Debug for LocalFutureObj<'_, T> {
67	0	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
68	0	f.debug_struct("LocalFutureObj").finish()
69	0	}
70		}
71
72		impl<'a, T> From<FutureObj<'a, T>> for LocalFutureObj<'a, T> {
73		#[inline]
74	0	fn from(f: FutureObj<'a, T>) -> Self {
75	0	f.0
76	0	}
77		}
78
79		impl<T> Future for LocalFutureObj<'_, T> {
80		type Output = T;
81
82		#[inline]
83	0	fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<T> {
84	0	unsafe { Pin::new_unchecked(&mut *self.future).poll(cx) }
85	0	}
86		}
87
88		impl<T> Drop for LocalFutureObj<'_, T> {
89	0	fn drop(&mut self) {
90	0	unsafe { (self.drop_fn)(self.future) }
91	0	} Unexecuted instantiation: <futures_task::future_obj::LocalFutureObj<()> as core::ops::drop::Drop>::drop Unexecuted instantiation: <futures_task::future_obj::LocalFutureObj<_> as core::ops::drop::Drop>::drop
92		}
93
94		/// A custom trait object for polling futures, roughly akin to
95		/// `Box<dyn Future<Output = T> + Send + 'a>`.
96		///
97		/// This custom trait object was introduced as currently it is not possible to
98		/// take `dyn Trait` by value and `Box<dyn Trait>` is not available in no_std
99		/// contexts.
100		///
101		/// You should generally not need to use this type outside of `no_std` or when
102		/// implementing `Spawn`, consider using `BoxFuture` instead.
103		pub struct FutureObj<'a, T>(LocalFutureObj<'a, T>);
104
105		impl<T> Unpin for FutureObj<'_, T> {}
106		unsafe impl<T> Send for FutureObj<'_, T> {}
107
108		impl<'a, T> FutureObj<'a, T> {
109		/// Create a `FutureObj` from a custom trait object representation.
110		#[inline]
111	0	pub fn new<F: UnsafeFutureObj<'a, T> + Send>(f: F) -> Self {
112	0	Self(LocalFutureObj::new(f))
113	0	} Unexecuted instantiation: <futures_task::future_obj::FutureObj<()>>::new::<alloc::boxed::Box<dyn core::future::future::Future<Output = ()> + core::marker::Send>> Unexecuted instantiation: <futures_task::future_obj::FutureObj<()>>::new::<core::pin::Pin<alloc::boxed::Box<dyn core::future::future::Future<Output = ()> + core::marker::Send>>>
114		}
115
116		impl<T> fmt::Debug for FutureObj<'_, T> {
117	0	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
118	0	f.debug_struct("FutureObj").finish()
119	0	}
120		}
121
122		impl<T> Future for FutureObj<'_, T> {
123		type Output = T;
124
125		#[inline]
126	0	fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<T> {
127	0	Pin::new(&mut self.0).poll(cx)
128	0	}
129		}
130
131		/// A custom implementation of a future trait object for `FutureObj`, providing
132		/// a vtable with drop support.
133		///
134		/// This custom representation is typically used only in `no_std` contexts,
135		/// where the default `Box`-based implementation is not available.
136		///
137		/// # Safety
138		///
139		/// See the safety notes on individual methods for what guarantees an
140		/// implementor must provide.
141		pub unsafe trait UnsafeFutureObj<'a, T>: 'a {
142		/// Convert an owned instance into a (conceptually owned) fat pointer.
143		///
144		/// # Safety
145		///
146		/// ## Implementor
147		///
148		/// The trait implementor must guarantee that it is safe to convert the
149		/// provided `*mut (dyn Future<Output = T> + 'a)` into a `Pin<&mut (dyn
150		/// Future<Output = T> + 'a)>` and call methods on it, non-reentrantly,
151		/// until `UnsafeFutureObj::drop` is called with it.
152		#[allow(clippy::unnecessary_safety_doc)]
153		fn into_raw(self) -> *mut (dyn Future<Output = T> + 'a);
154
155		/// Drops the future represented by the given fat pointer.
156		///
157		/// # Safety
158		///
159		/// ## Implementor
160		///
161		/// The trait implementor must guarantee that it is safe to call this
162		/// function once per `into_raw` invocation.
163		///
164		/// ## Caller
165		///
166		/// The caller must ensure:
167		///
168		/// * the pointer passed was obtained from an `into_raw` invocation from
169		/// this same trait object
170		/// * the pointer is not currently in use as a `Pin<&mut (dyn Future<Output
171		/// = T> + 'a)>`
172		/// * the pointer must not be used again after this function is called
173		unsafe fn drop(ptr: *mut (dyn Future<Output = T> + 'a));
174		}
175
176		unsafe impl<'a, T, F> UnsafeFutureObj<'a, T> for &'a mut F
177		where
178		F: Future<Output = T> + Unpin + 'a,
179		{
180	0	fn into_raw(self) -> *mut (dyn Future<Output = T> + 'a) {
181	0	self as *mut dyn Future<Output = T>
182	0	}
183
184	0	unsafe fn drop(_ptr: *mut (dyn Future<Output = T> + 'a)) {}
185		}
186
187		unsafe impl<'a, T> UnsafeFutureObj<'a, T> for &'a mut (dyn Future<Output = T> + Unpin + 'a) {
188	0	fn into_raw(self) -> *mut (dyn Future<Output = T> + 'a) {
189	0	self as *mut dyn Future<Output = T>
190	0	}
191
192	0	unsafe fn drop(_ptr: *mut (dyn Future<Output = T> + 'a)) {}
193		}
194
195		unsafe impl<'a, T, F> UnsafeFutureObj<'a, T> for Pin<&'a mut F>
196		where
197		F: Future<Output = T> + 'a,
198		{
199	0	fn into_raw(self) -> *mut (dyn Future<Output = T> + 'a) {
200	0	unsafe { self.get_unchecked_mut() as *mut dyn Future<Output = T> }
201	0	}
202
203	0	unsafe fn drop(_ptr: *mut (dyn Future<Output = T> + 'a)) {}
204		}
205
206		unsafe impl<'a, T> UnsafeFutureObj<'a, T> for Pin<&'a mut (dyn Future<Output = T> + 'a)> {
207	0	fn into_raw(self) -> *mut (dyn Future<Output = T> + 'a) {
208	0	unsafe { self.get_unchecked_mut() as *mut dyn Future<Output = T> }
209	0	}
210
211	0	unsafe fn drop(_ptr: *mut (dyn Future<Output = T> + 'a)) {}
212		}
213
214		#[cfg(feature = "alloc")]
215		mod if_alloc {
216		use super::*;
217		use alloc::boxed::Box;
218
219		unsafe impl<'a, T, F> UnsafeFutureObj<'a, T> for Box<F>
220		where
221		F: Future<Output = T> + 'a,
222		{
223	0	fn into_raw(self) -> *mut (dyn Future<Output = T> + 'a) {
224	0	Box::into_raw(self)
225	0	}
226
227	0	unsafe fn drop(ptr: *mut (dyn Future<Output = T> + 'a)) {
228	0	drop(unsafe { Box::from_raw(ptr.cast::<F>()) })
229	0	}
230		}
231
232		unsafe impl<'a, T: 'a> UnsafeFutureObj<'a, T> for Box<dyn Future<Output = T> + 'a> {
233	0	fn into_raw(self) -> *mut (dyn Future<Output = T> + 'a) {
234	0	Box::into_raw(self)
235	0	}
236
237	0	unsafe fn drop(ptr: *mut (dyn Future<Output = T> + 'a)) {
238	0	drop(unsafe { Box::from_raw(ptr) })
239	0	}
240		}
241
242		unsafe impl<'a, T: 'a> UnsafeFutureObj<'a, T> for Box<dyn Future<Output = T> + Send + 'a> {
243	0	fn into_raw(self) -> *mut (dyn Future<Output = T> + 'a) {
244	0	Box::into_raw(self)
245	0	}
246
247	0	unsafe fn drop(ptr: *mut (dyn Future<Output = T> + 'a)) {
248	0	drop(unsafe { Box::from_raw(ptr) })
249	0	}
250		}
251
252		unsafe impl<'a, T, F> UnsafeFutureObj<'a, T> for Pin<Box<F>>
253		where
254		F: Future<Output = T> + 'a,
255		{
256	0	fn into_raw(self) -> *mut (dyn Future<Output = T> + 'a) {
257	0	let mut this = mem::ManuallyDrop::new(self);
258	0	unsafe { this.as_mut().get_unchecked_mut() as *mut _ }
259	0	}
260
261	0	unsafe fn drop(ptr: *mut (dyn Future<Output = T> + 'a)) {
262	0	drop(Pin::from(unsafe { Box::from_raw(ptr) }))
263	0	}
264		}
265
266		unsafe impl<'a, T: 'a> UnsafeFutureObj<'a, T> for Pin<Box<dyn Future<Output = T> + 'a>> {
267	0	fn into_raw(self) -> *mut (dyn Future<Output = T> + 'a) {
268	0	let mut this = mem::ManuallyDrop::new(self);
269	0	unsafe { this.as_mut().get_unchecked_mut() as *mut _ }
270	0	}
271
272	0	unsafe fn drop(ptr: *mut (dyn Future<Output = T> + 'a)) {
273	0	drop(Pin::from(unsafe { Box::from_raw(ptr) }))
274	0	}
275		}
276
277		unsafe impl<'a, T: 'a> UnsafeFutureObj<'a, T> for Pin<Box<dyn Future<Output = T> + Send + 'a>> {
278	0	fn into_raw(self) -> *mut (dyn Future<Output = T> + 'a) {
279	0	let mut this = mem::ManuallyDrop::new(self);
280	0	unsafe { this.as_mut().get_unchecked_mut() as *mut _ }
281	0	}
282
283	0	unsafe fn drop(ptr: *mut (dyn Future<Output = T> + 'a)) {
284	0	drop(Pin::from(unsafe { Box::from_raw(ptr) }))
285	0	}
286		}
287
288		impl<'a, F: Future<Output = ()> + Send + 'a> From<Box<F>> for FutureObj<'a, ()> {
289	0	fn from(boxed: Box<F>) -> Self {
290	0	Self::new(boxed)
291	0	}
292		}
293
294		impl<'a> From<Box<dyn Future<Output = ()> + Send + 'a>> for FutureObj<'a, ()> {
295	0	fn from(boxed: Box<dyn Future<Output = ()> + Send + 'a>) -> Self {
296	0	Self::new(boxed)
297	0	}
298		}
299
300		impl<'a, F: Future<Output = ()> + Send + 'a> From<Pin<Box<F>>> for FutureObj<'a, ()> {
301	0	fn from(boxed: Pin<Box<F>>) -> Self {
302	0	Self::new(boxed)
303	0	}
304		}
305
306		impl<'a> From<Pin<Box<dyn Future<Output = ()> + Send + 'a>>> for FutureObj<'a, ()> {
307	0	fn from(boxed: Pin<Box<dyn Future<Output = ()> + Send + 'a>>) -> Self {
308	0	Self::new(boxed)
309	0	}
310		}
311
312		impl<'a, F: Future<Output = ()> + 'a> From<Box<F>> for LocalFutureObj<'a, ()> {
313	0	fn from(boxed: Box<F>) -> Self {
314	0	Self::new(boxed)
315	0	}
316		}
317
318		impl<'a> From<Box<dyn Future<Output = ()> + 'a>> for LocalFutureObj<'a, ()> {
319	0	fn from(boxed: Box<dyn Future<Output = ()> + 'a>) -> Self {
320	0	Self::new(boxed)
321	0	}
322		}
323
324		impl<'a, F: Future<Output = ()> + 'a> From<Pin<Box<F>>> for LocalFutureObj<'a, ()> {
325	0	fn from(boxed: Pin<Box<F>>) -> Self {
326	0	Self::new(boxed)
327	0	}
328		}
329
330		impl<'a> From<Pin<Box<dyn Future<Output = ()> + 'a>>> for LocalFutureObj<'a, ()> {
331	0	fn from(boxed: Pin<Box<dyn Future<Output = ()> + 'a>>) -> Self {
332	0	Self::new(boxed)
333	0	}
334		}
335		}