src/cached_inode.rs


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use crate::disk::data_block::{Block, DataBlock};
use crate::disk::inode::Inode;

pub struct CachedInode {
    pub inode: Inode,
    pub index: usize,
    pub dirty: bool,
}

#[derive(Clone)]
pub struct CachedBlock<T: Block> {
    pub block: T,
    pub index: usize,
    pub dirty: bool,
}

impl<T: Block> CachedBlock<T> {
    fn cast<U: Block>(&self) -> CachedBlock<U> {
        unsafe { std::mem::transmute_copy(&self) }
    }
}

pub fn convert_mut<U: Block, T: Block>(input_block: &mut CachedBlock<U>) -> &mut CachedBlock<T> {
    let ptr = input_block as *const CachedBlock<U> as *mut u8;
    let block = ptr.cast::<CachedBlock<T>>();
    unsafe { &mut *block }
}

pub fn convert<U: Block, T: Block>(input_block: &CachedBlock<U>) -> &CachedBlock<T> {
    let ptr = input_block as *const CachedBlock<U> as *mut u8;
    let block = ptr.cast::<CachedBlock<T>>();
    unsafe { &*block }
}