Struct swap::file::FilePageState

struct FilePageState(u32);

u32 to pack the state of a page on the file.

• MSB: Whether the page on file is freed. (1: freed, 2: allocated)
• lower 31 bits:
  • The corresponding page index if the file page is allocated.
  • The file page index + 1 of next freed file page if the file page is freed. Zero means it is the last page in the free list.

Tuple Fields

0: u32

Implementations

impl FilePageState

const FREED_BIT_MASK: u32 = 2_147_483_648u32

fn freed_state(first_freed_page: Option<usize>) -> Self

fn allocated_state(idx_page: usize) -> Option<Self>

fn is_freed(&self) -> bool

fn next_file_freed_idx(&self) -> Option<Option<usize>>

This is valid only if the page is freed.

fn idx_page(&self) -> Option<usize>

This is valid only if the page is allocated.

Trait Implementations

impl Debug for FilePageState

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

Formats the value using the given formatter.