Struct elysees::Arc

#[repr(transparent)]pub struct Arc<T: ?Sized> { /* fields omitted */ }

An atomically reference counted shared pointer

See the documentation for Arc in the standard library. Unlike the standard library Arc, this Arc holds a pointer to the T instead of to the entire ArcInner. This makes the struct FFI-compatible, and allows a variety of pointer casts, e.g. &[Arc<T>] to &[&T].

  std::sync::Arc<T>     elysees::Arc<T>
  |                     |
  v                     v
 --------------------------------------
| RefCount            | T (data)       | [ArcInner<T>]
 --------------------------------------

This means that this is a direct pointer to its contained data (and can be read from by both C/C++ and Rust)

This is very useful if you have an Arc-containing struct shared between Rust and C/C++, and wish for C/C++ to be able to read the data behind the Arc without incurring an FFI call overhead. This also enables a variety of useful casts, which are provided as safe functions by the library, e.g. &Arc -> &*const T, which can help with safe implementation of complex ByAddress datastructures

Implementations

impl<T> Arc<T>

pub fn new(data: T) -> Self

Construct an Arc<T>

impl<T: ?Sized> Arc<T>

pub fn borrow_arc(&self) -> ArcBorrow<'_, T>

Borrow this Arc<T> as an ArcBorrow<T>

pub fn leak(this: Arc<T>) -> ArcBorrow<'static, T>

Leak this Arc<T>, getting an ArcBorrow<'static, T>

You can call the get method on the returned ArcBorrow to get an &'static T. Note that using this can (obviously) cause memory leaks!

pub fn into_raw(this: Self) -> *const T

Convert the Arc<T> to a raw pointer, suitable for use across FFI

Note: This returns a pointer to the data T, which is offset in the allocation.

pub fn as_ptr(this: &Arc<T>) -> *const T

Get the raw pointer underlying this Arc<T>

pub unsafe fn from_raw(ptr: *const T) -> Arc<T>

Convert the Arc<T> from a raw pointer obtained from into_raw()

Note: This raw pointer will be offset in the allocation and must be preceded by the atomic count.

Safety

This function must be called with a pointer obtained from into_raw(), which is then invalidated.

pub fn is_unique(&self) -> bool

Whether or not the Arc is uniquely owned (is the refcount 1?).

pub fn try_unique(this: Self) -> Result<ArcBox<T>, Arc<T>>

Try to convert this Arc to an ArcBox if it is unique

pub fn count(this: &Arc<T>, ordering: LoadOrdering) -> usize

Get the reference count of this Arc with a given ordering

pub fn ptr_eq(this: &Self, other: &Self) -> bool

Compare two Arcs via pointer equality. Will only return true if they come from the same allocation

impl<T: Clone> Arc<T>

pub fn make_mut(this: &mut Self) -> &mut T

Makes a mutable reference to the ArcHandle, cloning if necessary

This is functionally equivalent to Arc::make_mut from the standard library.

If this ArcHandle is uniquely owned, make_mut() will provide a mutable reference to the contents. If not, make_mut() will create a new ArcHandle with a copy of the contents, update this to point to it, and provide a mutable reference to its contents.

This is useful for implementing copy-on-write schemes where you wish to avoid copying things if your Arc is not shared.

pub fn unique(this: Self) -> ArcBox<T>

Convert this Arc to an ArcBox, cloning the internal data if necessary for uniqueness

Trait Implementations

impl<S: ?Sized + SliceDst> AllocSliceDst<S> for Arc<S>

unsafe fn new_slice_dst<I>(len: usize, init: I) -> Self where
    I: FnOnce(NonNull<S>), 

Create a new custom slice DST.

impl<T: ?Sized> AsRef<*const T> for Arc<T>

fn as_ref(&self) -> &*const T

Performs the conversion.

impl<T: ?Sized> AsRef<*mut T> for Arc<T>

fn as_ref(&self) -> &*mut T

Performs the conversion.

impl<'a, T: ?Sized> AsRef<Arc<T>> for ArcBorrow<'a, T>

fn as_ref(&self) -> &Arc<T>

Performs the conversion.

impl<T: ?Sized> AsRef<NonNull<T>> for Arc<T>

fn as_ref(&self) -> &NonNull<T>

Performs the conversion.

impl<T: ?Sized> AsRef<T> for Arc<T>

fn as_ref(&self) -> &T

Performs the conversion.

impl<'a, T: ?Sized> Borrow<Arc<T>> for ArcBorrow<'a, T>

fn borrow(&self) -> &Arc<T>

Immutably borrows from an owned value.

impl<T: ?Sized> Borrow<T> for Arc<T>

fn borrow(&self) -> &T

Immutably borrows from an owned value.

impl<T: ?Sized> Clone for Arc<T>

fn clone(&self) -> Self

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T: ?Sized> CloneStableDeref for Arc<T>

impl<T: ?Sized + Debug> Debug for Arc<T>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<T: Default> Default for Arc<T>

fn default() -> Arc<T>

Returns the "default value" for a type.

impl<T: ?Sized> Deref for Arc<T>

type Target = T

The resulting type after dereferencing.

fn deref(&self) -> &T

Dereferences the value.

impl<T: ?Sized + Display> Display for Arc<T>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<T: ?Sized> Drop for Arc<T>

fn drop(&mut self)

Executes the destructor for this type.

impl<T: ?Sized + Eq> Eq for Arc<T>

impl<T: ?Sized + Erasable> ErasablePtr for Arc<T>

fn erase(this: Self) -> ErasedPtr

Turn this erasable pointer into an erased pointer.

unsafe fn unerase(this: ErasedPtr) -> Self

Unerase this erased pointer.

impl<T> From<T> for Arc<T>

fn from(t: T) -> Self

Performs the conversion.

impl<T: ?Sized + Hash> Hash for Arc<T>

fn hash<H: Hasher>(&self, state: &mut H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given Hasher.

impl<T: ?Sized + Ord> Ord for Arc<T>

fn cmp(&self, other: &Arc<T>) -> Ordering

This method returns an Ordering between self and other.

#[must_use]fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

#[must_use]fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

#[must_use]fn clamp(self, min: Self, max: Self) -> Self

🔬 This is a nightly-only experimental API. (clamp)

Restrict a value to a certain interval.

impl<T: ?Sized + PartialEq> PartialEq<Arc<T>> for Arc<T>

fn eq(&self, other: &Arc<T>) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Arc<T>) -> bool

This method tests for !=.

impl<T: ?Sized + PartialOrd> PartialOrd<Arc<T>> for Arc<T>

fn partial_cmp(&self, other: &Arc<T>) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Arc<T>) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Arc<T>) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Arc<T>) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Arc<T>) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl<T: ?Sized> Pointer for Arc<T>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<T: ?Sized + Sync + Send> Send for Arc<T>

impl<T: ?Sized> StableDeref for Arc<T>

impl<T> Stowable for Arc<T>

impl<T: ?Sized + Sync + Send> Sync for Arc<T>

impl<S: ?Sized + SliceDst> TryAllocSliceDst<S> for Arc<S>

unsafe fn try_new_slice_dst<I, E>(len: usize, init: I) -> Result<Self, E> where
    I: FnOnce(NonNull<S>) -> Result<(), E>, 

Create a new custom slice DST with a fallible initialization function.

impl<T: ?Sized> UnionAlign for Arc<T> where
    Arc<T>: ErasablePtr, 

fn left<B: UnionAlign>(this: Self) -> Union2<Self, B>

fn right<A: UnionAlign>(this: Self) -> Union2<A, Self>

fn a<B: UnionAlign, C: UnionAlign, D: UnionAlign>(
    this: Self
) -> Union4<Self, B, C, D>

fn b<A: UnionAlign, C: UnionAlign, D: UnionAlign>(
    this: Self
) -> Union4<A, Self, C, D>

fn c<A: UnionAlign, B: UnionAlign, D: UnionAlign>(
    this: Self
) -> Union4<A, B, Self, D>

fn d<A: UnionAlign, B: UnionAlign, C: UnionAlign>(
    this: Self
) -> Union4<A, B, C, Self>