Struct PageData 

pub struct PageData { /* private fields */ }

Raw page data as an owned byte buffer.

The length always matches the database page size. Fresh pages stay owned until the first clone, then lazily promote to Arc<[u8]> for shared copy-on-write snapshots.

Implementations

impl PageData

pub fn zeroed(size: PageSize) -> Self

Create a zero-filled page of the given size.

pub fn from_vec(data: Vec<u8>) -> Self

Create from existing bytes. The caller must ensure the length matches the page size.

pub fn from_shared(bytes: Arc<[u8]>) -> Self

Create from an already shared immutable page snapshot.

pub fn as_bytes(&self) -> &[u8]

Get the page data as a byte slice.

pub fn image_token(&self) -> u64

Cheap identity for this exact immutable page image.

Clones preserve the token because they expose identical bytes. Any mutable access assigns a fresh token before returning the mutable slice, so caches can key on (page_no, image_token) instead of re-hashing the whole page to detect page-image changes.

pub fn as_bytes_mut(&mut self) -> &mut [u8]

Get the page data as a mutable byte slice.

This performs a clone if the data is shared (Copy-On-Write).

pub fn is_single_owner_owned(&self) -> bool

Returns true when this page is backed by single-owner Owned bytes whose shared-snapshot cache has not yet been materialised.

Callers can use this as a cheap probe before mutating via as_bytes_mut: a true result guarantees that the subsequent mutable borrow will NOT trigger a copy-on-write clone (Arc::make_mut) and thus stays allocation-free.

pub fn try_zero_extend_owned_to(&mut self, new_len: usize) -> bool

Extend an owned page buffer with zero bytes in place.

Returns true when the underlying representation stayed owned and was extended without promoting/cloning through a shared snapshot.

pub fn len(&self) -> usize

Get the length in bytes.

pub fn is_empty(&self) -> bool

Returns true if the page data is empty (should never be true for valid pages).

pub fn into_vec(self) -> Vec<u8>

Consume self and return the inner Vec<u8>.

If the data is shared, this clones into a new Vec.

Trait Implementations

impl AsMut<[u8]> for PageData

fn as_mut(&mut self) -> &mut [u8]

Converts this type into a mutable reference of the (usually inferred) input type.

impl AsRef<[u8]> for PageData

fn as_ref(&self) -> &[u8]

Converts this type into a shared reference of the (usually inferred) input type.

impl Clone for PageData

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for PageData

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

Formats the value using the given formatter.

impl Eq for PageData

impl PartialEq for PageData

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