Struct portable_atomic::AtomicI8

#[repr(C, align(1))]
pub struct AtomicI8 { /* private fields */ }

An integer type which can be safely shared between threads.

This type has the same in-memory representation as the underlying integer type, i8.

If the compiler or the platform supports atomic loads and stores of i8, this type is a wrapper for the standard library’s AtomicI8, otherwise synchronizes using global locks. You can call AtomicI8::is_lock_free() to check whether atomic instructions or locks will be used.

Implementations

impl AtomicI8

pub const fn new(v: i8) -> Self

Creates a new atomic integer.

pub fn is_lock_free() -> bool

Returns true if operations on values of this type are lock-free.

If the compiler or the platform doesn’t support the necessary atomic instructions, global locks for every potentially concurrent atomic operation will be used.

pub const fn is_always_lock_free() -> bool

Returns true if operations on values of this type are lock-free.

If the compiler or the platform doesn’t support the necessary atomic instructions, global locks for every potentially concurrent atomic operation will be used.

Note: If the atomic operation relies on dynamic CPU feature detection, this type may be lock-free even if the function returns false.

pub fn get_mut(&mut self) -> &mut i8

Returns a mutable reference to the underlying integer.

This is safe because the mutable reference guarantees that no other threads are concurrently accessing the atomic data.

pub fn into_inner(self) -> i8

Consumes the atomic and returns the contained value.

This is safe because passing self by value guarantees that no other threads are concurrently accessing the atomic data.

pub fn load(&self, order: Ordering) -> i8

Loads a value from the atomic integer.

load takes an Ordering argument which describes the memory ordering of this operation. Possible values are SeqCst, Acquire and Relaxed.

Panics

Panics if order is Release or AcqRel.

pub fn store(&self, val: i8, order: Ordering)

Stores a value into the atomic integer.

store takes an Ordering argument which describes the memory ordering of this operation. Possible values are SeqCst, Release and Relaxed.

Panics

Panics if order is Acquire or AcqRel.

pub fn swap(&self, val: i8, order: Ordering) -> i8

Stores a value into the atomic integer, returning the previous value.

swap takes an Ordering argument which describes the memory ordering of this operation. All ordering modes are possible. Note that using Acquire makes the store part of this operation Relaxed, and using Release makes the load part Relaxed.

pub fn compare_exchange(
    &self,
    current: i8,
    new: i8,
    success: Ordering,
    failure: Ordering
) -> Result<i8, i8>

Stores a value into the atomic integer if the current value is the same as the current value.

The return value is a result indicating whether the new value was written and containing the previous value. On success this value is guaranteed to be equal to current.

compare_exchange takes two Ordering arguments to describe the memory ordering of this operation. success describes the required ordering for the read-modify-write operation that takes place if the comparison with current succeeds. failure describes the required ordering for the load operation that takes place when the comparison fails. Using Acquire as success ordering makes the store part of this operation Relaxed, and using Release makes the successful load Relaxed. The failure ordering can only be SeqCst, Acquire or Relaxed and must be equivalent to or weaker than the success ordering.

pub fn compare_exchange_weak(
    &self,
    current: i8,
    new: i8,
    success: Ordering,
    failure: Ordering
) -> Result<i8, i8>

Stores a value into the atomic integer if the current value is the same as the current value. Unlike compare_exchange this function is allowed to spuriously fail even when the comparison succeeds, which can result in more efficient code on some platforms. The return value is a result indicating whether the new value was written and containing the previous value.

compare_exchange_weak takes two Ordering arguments to describe the memory ordering of this operation. success describes the required ordering for the read-modify-write operation that takes place if the comparison with current succeeds. failure describes the required ordering for the load operation that takes place when the comparison fails. Using Acquire as success ordering makes the store part of this operation Relaxed, and using Release makes the successful load Relaxed. The failure ordering can only be SeqCst, Acquire or Relaxed and must be equivalent to or weaker than the success ordering.

pub fn fetch_add(&self, val: i8, order: Ordering) -> i8

Adds to the current value, returning the previous value.

This operation wraps around on overflow.

fetch_add takes an Ordering argument which describes the memory ordering of this operation. All ordering modes are possible. Note that using Acquire makes the store part of this operation Relaxed, and using Release makes the load part Relaxed.

pub fn fetch_sub(&self, val: i8, order: Ordering) -> i8

Subtracts from the current value, returning the previous value.

This operation wraps around on overflow.

fetch_sub takes an Ordering argument which describes the memory ordering of this operation. All ordering modes are possible. Note that using Acquire makes the store part of this operation Relaxed, and using Release makes the load part Relaxed.

pub fn fetch_and(&self, val: i8, order: Ordering) -> i8

Bitwise “and” with the current value.

Performs a bitwise “and” operation on the current value and the argument val, and sets the new value to the result.

Returns the previous value.

fetch_and takes an Ordering argument which describes the memory ordering of this operation. All ordering modes are possible. Note that using Acquire makes the store part of this operation Relaxed, and using Release makes the load part Relaxed.

pub fn fetch_nand(&self, val: i8, order: Ordering) -> i8

Bitwise “nand” with the current value.

Performs a bitwise “nand” operation on the current value and the argument val, and sets the new value to the result.

Returns the previous value.

fetch_nand takes an Ordering argument which describes the memory ordering of this operation. All ordering modes are possible. Note that using Acquire makes the store part of this operation Relaxed, and using Release makes the load part Relaxed.

pub fn fetch_or(&self, val: i8, order: Ordering) -> i8

Bitwise “or” with the current value.

Performs a bitwise “or” operation on the current value and the argument val, and sets the new value to the result.

Returns the previous value.

fetch_or takes an Ordering argument which describes the memory ordering of this operation. All ordering modes are possible. Note that using Acquire makes the store part of this operation Relaxed, and using Release makes the load part Relaxed.

pub fn fetch_xor(&self, val: i8, order: Ordering) -> i8

Bitwise “xor” with the current value.

Performs a bitwise “xor” operation on the current value and the argument val, and sets the new value to the result.

Returns the previous value.

fetch_xor takes an Ordering argument which describes the memory ordering of this operation. All ordering modes are possible. Note that using Acquire makes the store part of this operation Relaxed, and using Release makes the load part Relaxed.

pub fn fetch_update<F>(
    &self,
    set_order: Ordering,
    fetch_order: Ordering,
    f: F
) -> Result<i8, i8> where
    F: FnMut(i8) -> Option<i8>, 

Fetches the value, and applies a function to it that returns an optional new value. Returns a Result of Ok(previous_value) if the function returned Some(_), else Err(previous_value).

Note: This may call the function multiple times if the value has been changed from other threads in the meantime, as long as the function returns Some(_), but the function will have been applied only once to the stored value.

fetch_update takes two Ordering arguments to describe the memory ordering of this operation. The first describes the required ordering for when the operation finally succeeds while the second describes the required ordering for loads. These correspond to the success and failure orderings of compare_exchange respectively.

Using Acquire as success ordering makes the store part of this operation Relaxed, and using Release makes the final successful load Relaxed. The (failed) load ordering can only be SeqCst, Acquire or Relaxed and must be equivalent to or weaker than the success ordering.

pub fn fetch_max(&self, val: i8, order: Ordering) -> i8

Maximum with the current value.

Finds the maximum of the current value and the argument val, and sets the new value to the result.

Returns the previous value.

fetch_max takes an Ordering argument which describes the memory ordering of this operation. All ordering modes are possible. Note that using Acquire makes the store part of this operation Relaxed, and using Release makes the load part Relaxed.

pub fn fetch_min(&self, val: i8, order: Ordering) -> i8

Minimum with the current value.

Finds the minimum of the current value and the argument val, and sets the new value to the result.

Returns the previous value.

fetch_min takes an Ordering argument which describes the memory ordering of this operation. All ordering modes are possible. Note that using Acquire makes the store part of this operation Relaxed, and using Release makes the load part Relaxed.

Trait Implementations

impl Debug for AtomicI8

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

Formats the value using the given formatter.

impl Default for AtomicI8

fn default() -> Self

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for AtomicI8

This is supported on crate feature serde only.

fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> where
    D: Deserializer<'de>, 

Deserialize this value from the given Serde deserializer.

impl From<i8> for AtomicI8

fn from(v: i8) -> Self

Performs the conversion.

impl Serialize for AtomicI8

This is supported on crate feature serde only.

fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> where
    S: Serializer, 

Serialize this value into the given Serde serializer.

impl RefUnwindSafe for AtomicI8