pub struct OwningPtr<'a, A: IsAligned = Aligned>(/* private fields */);Expand description
Type-erased Box-like pointer to some unknown type chosen when constructing this type.
Conceptually represents ownership of whatever data is being pointed to and so is
responsible for calling its Drop impl. This pointer is not responsible for freeing
the memory pointed to by this pointer as it may be pointing to an element in a Vec or
to a local in a function etc.
This type tries to act “borrow-like” which means that:
- Pointer should be considered exclusive and mutable. It cannot be cloned as this would lead to aliased mutability and potentially use after free bugs.
- It must always point to a valid value of whatever the pointee type is.
- The lifetime
'aaccurately represents how long the pointer is valid for. - If
AisAligned, the pointer must always be properly aligned for the unknown pointee type.
It may be helpful to think of this type as similar to &'a mut ManuallyDrop<dyn Any> but
without the metadata and able to point to data that does not correspond to a Rust type.
Implementations§
Source§impl<'a> OwningPtr<'a, Aligned>
impl<'a> OwningPtr<'a, Aligned>
Sourcepub fn to_unaligned(self) -> OwningPtr<'a, Unaligned>
pub fn to_unaligned(self) -> OwningPtr<'a, Unaligned>
Removes the alignment requirement of this pointer
Source§impl<A: IsAligned> OwningPtr<'_, A>
impl<A: IsAligned> OwningPtr<'_, A>
Sourcepub unsafe fn byte_offset(self, count: isize) -> Self
pub unsafe fn byte_offset(self, count: isize) -> Self
Calculates the offset from a pointer.
As the pointer is type-erased, there is no size information available. The provided
count parameter is in raw bytes.
See also: ptr::offset
§Safety
- The offset cannot make the existing ptr null, or take it out of bounds for its allocation.
- If the
Atype parameter isAlignedthen the offset must not make the resulting pointer be unaligned for the pointee type. - The value pointed by the resulting pointer must outlive the lifetime of this pointer.
Sourcepub unsafe fn byte_add(self, count: usize) -> Self
pub unsafe fn byte_add(self, count: usize) -> Self
Calculates the offset from a pointer (convenience for .offset(count as isize)).
As the pointer is type-erased, there is no size information available. The provided
count parameter is in raw bytes.
See also: ptr::add
§Safety
- The offset cannot make the existing ptr null, or take it out of bounds for its allocation.
- If the
Atype parameter isAlignedthen the offset must not make the resulting pointer be unaligned for the pointee type. - The value pointed by the resulting pointer must outlive the lifetime of this pointer.
Source§impl<'a, A: IsAligned> OwningPtr<'a, A>
impl<'a, A: IsAligned> OwningPtr<'a, A>
Sourcepub unsafe fn new(inner: NonNull<u8>) -> Self
pub unsafe fn new(inner: NonNull<u8>) -> Self
Creates a new instance from a raw pointer.
§Safety
innermust point to valid value of whatever the pointee type is.- If the
Atype parameter isAlignedtheninnermust be properly aligned for the pointee type. innermust have correct provenance to allow read and writes of the pointee type.- The lifetime
'amust be constrained such that thisOwningPtrwill stay valid and nothing else can read or mutate the pointee while thisOwningPtris live.
Sourcepub unsafe fn read<T>(self) -> T
pub unsafe fn read<T>(self) -> T
Consumes the OwningPtr to obtain ownership of the underlying data of type T.
§Safety
Tmust be the erased pointee type for thisOwningPtr.- If the type parameter
AisUnalignedthen this pointer must be be properly aligned for the pointee typeT.
Sourcepub unsafe fn drop_as<T>(self)
pub unsafe fn drop_as<T>(self)
Consumes the OwningPtr to drop the underlying data of type T.
§Safety
Tmust be the erased pointee type for thisOwningPtr.- If the type parameter
AisUnalignedthen this pointer must be be properly aligned for the pointee typeT.