Struct Counter 

pub struct Counter(/* private fields */);

An object representing a Zircon counter.

As essentially a subtype of Handle, it can be freely interconverted.

Implementations

impl Counter

pub fn create() -> Counter

Create a counter object.

This object contains an integer which can be read, written, incremented and decremented. Readers can wait on [zx::Signals::COUNTER_POSITIVE] and [zx::Signals::COUNTER_NON_POSITIVE] to react on the respective value changes.

See: zx_counter_create syscall.

Panics

If the kernel reports no memory available or the process’ job policy denies counter creation.

pub fn add(&self, value: i64) -> Result<(), Status>

Adds value to this counter.

pub fn read(&self) -> Result<i64, Status>

Reads the value of this counter.

pub fn write(&self, value: i64) -> Result<(), Status>

Sets the value of this counter to value.

Trait Implementations

impl AsHandleRef for Counter

fn as_handle_ref(&self) -> Unowned<'_, Handle>

Get a reference to the handle. One important use of such a reference is for object_wait_many.

fn raw_handle(&self) -> u32

Interpret the reference as a raw handle (an integer type). Two distinct handles will have different raw values (so it can perhaps be used as a key in a data structure).

fn signal_handle( &self, clear_mask: Signals, set_mask: Signals, ) -> Result<(), Status>

Set and clear userspace-accessible signal bits on an object. Wraps the zx_object_signal syscall.

fn wait_handle( &self, signals: Signals, deadline: Instant<MonotonicTimeline>, ) -> WaitResult

Waits on a handle. Wraps the zx_object_wait_one syscall.

fn wait_async_handle( &self, port: &Port, key: u64, signals: Signals, options: WaitAsyncOpts, ) -> Result<(), Status>

Causes packet delivery on the given port when the object changes state and matches signals. zx_object_wait_async syscall.

fn get_name(&self) -> Result<Name, Status>

Get the Property::NAME property for this object.

fn set_name(&self, name: &Name) -> Result<(), Status>

Set the Property::NAME property for this object.

fn basic_info(&self) -> Result<HandleBasicInfo, Status>

Wraps the zx_object_get_info syscall for the ZX_INFO_HANDLE_BASIC topic.

fn count_info(&self) -> Result<HandleCountInfo, Status>

Wraps the zx_object_get_info syscall for the ZX_INFO_HANDLE_COUNT topic.

fn get_koid(&self) -> Result<Koid, Status>

Returns the koid (kernel object ID) for this handle.

impl Debug for Counter

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

Formats the value using the given formatter.

impl Encodable for Counter

type Encoded = WireCounter

The wire type for the value.

const COPY_OPTIMIZATION: CopyOptimization<Self, Self::Encoded> = _

Whether the conversion from Self to Self::Encoded is equivalent to copying the raw bytes of Self.

impl EncodableOption for Counter

type EncodedOption = WireOptionalCounter

The wire type for the optional value.

impl<E> Encode<E> for Counter

where E: HandleEncoder + ?Sized,

fn encode( self, encoder: &mut E, out: &mut MaybeUninit<<Counter as Encodable>::Encoded>, ) -> Result<(), EncodeError>

Encodes this value into an encoder and output.

impl<E> EncodeOption<E> for Counter

where E: HandleEncoder + ?Sized,

fn encode_option( this: Option<Counter>, encoder: &mut E, out: &mut MaybeUninit<<Counter as EncodableOption>::EncodedOption>, ) -> Result<(), EncodeError>

Encodes this optional value into an encoder and output.

impl From<Counter> for Handle

fn from(x: Counter) -> Handle

Converts to this type from the input type.

impl From<Handle> for Counter

fn from(handle: Handle) -> Counter

Converts to this type from the input type.

impl FromWire<WireCounter> for Counter

fn from_wire(wire: WireCounter) -> Counter

Converts the given wire to this type.

const COPY_OPTIMIZATION: CopyOptimization<W, Self> = _

Whether the conversion from W to Self is equivalent to copying the raw bytes of W.

impl FromWireOption<WireOptionalCounter> for Counter

fn from_wire_option(wire: WireOptionalCounter) -> Option<Counter>

Converts the given wire to an option of this type.

impl HandleBased for Counter

fn duplicate_handle(&self, rights: Rights) -> Result<Self, Status>

Duplicate a handle, possibly reducing the rights available. Wraps the zx_handle_duplicate syscall.

fn replace_handle(self, rights: Rights) -> Result<Self, Status>

Create a replacement for a handle, possibly reducing the rights available. This invalidates the original handle. Wraps the zx_handle_replace syscall.

fn into_handle(self) -> Handle

Converts the value into its inner handle.

fn into_raw(self) -> u32

Converts the handle into it’s raw representation.

fn from_handle(handle: Handle) -> Self

Creates an instance of this type from a handle.

fn into_handle_based<H>(self) -> H

where H: HandleBased,

Creates an instance of another handle-based type from this value’s inner handle.

fn from_handle_based<H>(h: H) -> Self

where H: HandleBased,

Creates an instance of this type from the inner handle of another handle-based type.

fn is_invalid_handle(&self) -> bool

impl Hash for Counter

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

where __H: Hasher,

Feeds this value into the given Hasher.

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

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for Counter

fn cmp(&self, other: &Counter) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for Counter

fn eq(&self, other: &Counter) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for Counter

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

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

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

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

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

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

impl Eq for Counter

impl StructuralPartialEq for Counter