Enum Availability

#[repr(u32)]
pub enum Availability {
    Required = 1,
    Optional = 2,
    SameAsTarget = 3,
    Transitional = 4,
}

Describes the expected availability of the capability.

Some capabilities may not be present on all system configurations. In those cases, the availability will be declared as OPTIONAL along the chains of exposes/offers/uses, and the capability would be routed from void on system configurations where it does not make sense to route or provide a particular capability (e.g. graphical capabilities on a headless system).

Variants

Required = 1

The capability must be available. Failure to route the capability is an error.

Optional = 2

Inside a use declaration: the component can function if it fails to obtain the capability.

Inside an offer/expose declaration: the capability may not be available in some system configurations. As a corollary, the target component must not have a required dependency on the capability.

SameAsTarget = 3

If the target of the corresponding offer or expose declaration requires the capability, then the behavior is equivalent to required. If the target has an optional dependency on the capability, then the behavior is equivalent to optional. This is useful for container components that would like to change their routing availability based on ones inside.

This value is not allowed inside a use declaration.

Transitional = 4

The source may omit the route completely without even having to route from void.

[TRANSITIONAL] is used for soft transitions that introduce new capabilities.

Implementations

impl Availability

pub fn from_primitive(prim: u32) -> Option<Self>

pub const fn into_primitive(self) -> u32

pub fn is_unknown(&self) -> bool

👎Deprecated: Strict enums should not use is_unknown

Trait Implementations

impl Clone for Availability

fn clone(&self) -> Availability

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Availability

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

Formats the value using the given formatter.

impl<D: ResourceDialect> Decode<Availability, D> for Availability

fn new_empty() -> Self

Creates a valid instance of Self. The specific value does not matter, since it will be overwritten by decode.

unsafe fn decode( &mut self, decoder: &mut Decoder<'_, D>, offset: usize, _depth: Depth, ) -> Result<()>

Decodes an object of type T from the decoder’s buffers into self.

impl<D: ResourceDialect> Encode<Availability, D> for Availability

unsafe fn encode( self, encoder: &mut Encoder<'_, D>, offset: usize, _depth: Depth, ) -> Result<()>

Encodes the object into the encoder’s buffers. Any handles stored in the object are swapped for Handle::INVALID.

impl Hash for Availability

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, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for Availability

fn cmp(&self, other: &Availability) -> 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 Availability

fn eq(&self, other: &Availability) -> 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 Availability

fn partial_cmp(&self, other: &Availability) -> 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 TypeMarker for Availability

type Owned = Availability

The owned Rust type which this FIDL type decodes into.

fn inline_align(_context: Context) -> usize

Returns the minimum required alignment of the inline portion of the encoded object. It must be a (nonzero) power of two.

fn inline_size(_context: Context) -> usize

Returns the size of the inline portion of the encoded object, including padding for alignment. Must be a multiple of inline_align.

fn encode_is_copy() -> bool

Returns true if the memory layout of Self::Owned matches the FIDL wire format and encoding requires no validation. When true, we can optimize encoding arrays and vectors of Self::Owned to a single memcpy.

fn decode_is_copy() -> bool

Returns true if the memory layout of Self::Owned matches the FIDL wire format and decoding requires no validation. When true, we can optimize decoding arrays and vectors of Self::Owned to a single memcpy.

impl ValueTypeMarker for Availability

type Borrowed<'a> = Availability

The Rust type to use for encoding. This is a particular Encode<Self> type cheaply obtainable from &Self::Owned. There are three cases:

fn borrow(value: &<Self as TypeMarker>::Owned) -> Self::Borrowed<'_>

Cheaply converts from &Self::Owned to Self::Borrowed.

impl Copy for Availability

impl Eq for Availability

impl StructuralPartialEq for Availability