Enum Error

pub enum Error {
    Invalid,
    Unspecified,
    ProtocolDeviation,
    NotFound,
    HandleAccessDenied,
    NoMemory,
    ConstraintsIntersectionEmpty,
    Pending,
    TooManyGroupChildCombinations,
    // some variants omitted
}

Regardless of which error code, any client retries should be very limited in number, if any.

A Error value should never be stored in a zx_status_t, since positive values in zx_status_t are deprecated.

Variants

Invalid

This is not a valid error value in this error enum. The server will never send this value as a failure code. This value is not treated as “success”. In some languages, a locally default-initialized Error instance will have this value until it is initialized with a valid positive error code.

Unspecified

Unspecified error.

This error code is used when no other error code applies, and the error is probably not due to problematic messages sent to the server via the channel delivering this error.

This error should be handled by the client as a generic error.

As one example, this error is used when a different client channel has closed from the client end unexpectedly (without sending [fuchsia.sysmem2/Node.Release] first), thereby causing failure of any nodes in the same tree or sub-tree. In this usage, the main thing that’s relevant is it isn’t the receiving client’s “fault” - no reason to be more specific since there’s probably nothing the receiving client could do about the error, at least not directly.

As another example, this error can be used if a syscall that is normally expected to succeed fails unexpectedly, and there’s no identified reason to “blame” the client.

A client should never require / depend on a particular cause of error continuing to result in UNSPECIFIED, as any particular error cause can potentially start resulting in a more specific error code in future.

ProtocolDeviation

A required field wasn’t set or a specified value was invalid. See the log for more info.

This is also used when a message is received from the client in the wrong order or in some way inconsistent with protocol rules.

NotFound

A client-specified object or ID was not found.

HandleAccessDenied

The object handle doesn’t have sufficient rights to perform the request.

NoMemory

The allocation could not be satisfied due to lack of available memory.

The memory exhaustion can be specific to the heap that was selected during constraints aggregation, so in some cases, this error can happen despite normal system RAM not being near exhaustion, depending on configured and selected heap(s).

ConstraintsIntersectionEmpty

The request is valid but cannot be satisfied, perhaps due to hardware limitations. This happens if participants involved in this allocation have incompatible constraints (empty intersection, roughly speaking). See the log for more info. In cases where a participant could potentially be treated as optional, see [BufferCollectionTokenGroup].

This can also happen if there aren’t enough buffers in a pre-existing collection to satisfy an additional token (including sub-tree of derived tokens) created with [fuchsia.sysmem2/BufferCollection.AttachToken].

This can also happen if a client’s node is under a group and a different group child is selected instead.

Pending

Allocation hasn’t been attempted yet. Calling [fuchsia.sysmem2/BufferCollection.WaitForAllBuffersAllocated] would (likely) block.

TooManyGroupChildCombinations

Too many BufferCollectionTokenGroup child token selection combinations exist and were considered, causing sysmem to give up on allocating rather than enumerate the rest.

Implementations

impl Error

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

pub fn from_primitive_allow_unknown(prim: u32) -> Self

pub fn unknown() -> Self

pub const fn into_primitive(self) -> u32

pub fn is_unknown(&self) -> bool

Trait Implementations

impl Clone for Error

fn clone(&self) -> Error

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Error

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

Formats the value using the given formatter.

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

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<Error, D> for Error

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 Error

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 Error

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

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

fn partial_cmp(&self, other: &Error) -> 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 Error

type Owned = Error

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 Error

type Borrowed<'a> = Error

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 Error

impl Eq for Error

impl StructuralPartialEq for Error