Enum OffsetSizeBytes

pub(crate) enum OffsetSizeBytes {
    One = 1,
    Two = 2,
    Three = 3,
    Four = 4,
}

Used to unpack offset array entries such as metadata dictionary offsets or object/array value offsets. Also used to unpack object field ids. These are always derived from a two-bit XXX_size_minus_one field in the corresponding header byte.

Variants

One = 1

Two = 2

Three = 3

Four = 4

Implementations

impl OffsetSizeBytes

pub(crate) fn try_new(offset_size_minus_one: u8) -> Result<Self, ArrowError>

Build from the offset_size_minus_one bits (see spec).

pub(crate) fn unpack_u32( &self, bytes: &[u8], index: usize, ) -> Result<u32, ArrowError>

Return one unsigned little-endian value from bytes.

• bytes – the byte buffer to index
• index – 0-based index into the buffer

Each value is self as u32 bytes wide (1, 2, 3 or 4), zero-extended to 32 bits as needed.

pub(crate) fn unpack_u32_at_offset( &self, bytes: &[u8], byte_offset: usize, offset_index: usize, ) -> Result<u32, ArrowError>

Return one unsigned little-endian value from bytes.

• bytes – the byte buffer to index
• byte_offset – number of bytes to skip before reading the first value (e.g. 1 to move past a header byte).
• offset_index – 0-based index after the skipped bytes (0 is the first value, 1 the next, …).

Each value is self as u32 bytes wide (1, 2, 3 or 4), zero-extended to 32 bits as needed.

Trait Implementations

impl Clone for OffsetSizeBytes

fn clone(&self) -> OffsetSizeBytes

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for OffsetSizeBytes

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

Formats the value using the given formatter.

impl PartialEq for OffsetSizeBytes

fn eq(&self, other: &OffsetSizeBytes) -> 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 Copy for OffsetSizeBytes

impl StructuralPartialEq for OffsetSizeBytes