Enum Contiguity 

#[non_exhaustive]
#[repr(u32)]
pub enum Contiguity {
    Unknown = 0,
    Contiguous = 1,
    NonContiguous = 2,
}

Whether a tensor’s memory is known to be physically contiguous (Tensor::contiguity).

Capture and other DMA engines without an IOMMU (the i.MX 8M Plus ISI, the vvcam ISP) can only write into physically contiguous memory. Only memory this crate allocated from a Linux DMA heap is known either way: the CMA heap is contiguous and the system heap is not. An imported fd, and every other kind of memory, is Unknown.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Unknown = 0

Not known: an imported fd, or memory not allocated from a DMA heap.

Contiguous = 1

Allocated from the CMA heap.

NonContiguous = 2

Allocated from the system heap.

Implementations

impl Contiguity

pub const fn code(self) -> u32

The shared code for this variant. Identical on every surface.

const, deliberately: a downstream binding that cannot write Variant = OtherEnum::Variant.code() in a #[pyclass] discriminant position (PyO3 requires a literal there) can still pin that literal to this value with a const _: () = assert!(...) – a build-time check instead of a hand-synced comment. See PyTensorMemory/PyPixelFormat in crates/python-common/src/tensor.rs for the consumer.

pub fn from_code(code: u32) -> Option<Self>

Reject an unknown code rather than guessing at one.

pub fn as_str(self) -> &'static str

The wire string form – stable, unlike Debug.

pub fn from_str_code(s: &str) -> Option<Self>

Reject an unknown string rather than guessing at one.

pub fn all() -> &'static [Self]

Every variant, for exhaustive cross-surface tests.

Trait Implementations

impl Clone for Contiguity

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for Contiguity

impl Debug for Contiguity

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

Formats the value using the given formatter.

impl Eq for Contiguity

impl Hash for Contiguity

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 PartialEq for Contiguity

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for Contiguity