Struct memory_pager::Pager

pub struct Pager {
    pub page_size: usize,
    pub pages: Vec<Option<Page>>,
    // some fields omitted
}

Memory pager instance. Manages Page instances.

Fields

page_size: usize

The size of each page held in memory.

pages: Vec<Option<Page>>

A vector of pages that are held in memory.

Methods

impl Pager

pub fn new(page_size: usize) -> Self

Create a new Pager instance with a page_size.

pub fn with_pages(page_size: usize, pages: Vec<Option<Page>>) -> Self

Create a new Pager instance with a page_size and pages. Useful to restore a Pager instance from disk.

pub fn get_mut_or_alloc(&mut self, page_num: usize) -> &mut Page

Get a Page mutably. The page will be allocated on first access.

pub fn get(&mut self, page_num: usize) -> Option<&Page>

Get a Page wrapped in an Option enum. Does not allocate on access.

pub fn get_mut(&mut self, page_num: usize) -> Option<&mut Page>

Get a mutable Page wrapped in an Option enum. Does not allocate on access.

pub fn len(&self) -> usize

Return the highest index number for the Pages held. Not exactly the "length" in the classical sence, but the same for all intents and purposes.

pub fn is_empty(&self) -> bool

check whether the length is zero.

Trait Implementations

impl Debug for Pager

fn fmt(&self, __arg_0: &mut Formatter) -> Result

Formats the value using the given formatter.

impl Default for Pager

Create a new Pager instance with a page_size of 1024.

fn default() -> Self

Returns the "default value" for a type.