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pub trait Block: Default {}
#[derive(Default)]
pub struct DataBlock([u8; 4096]);
impl Block for DataBlock {}
const FULL_MAP: u32 = 0b111_111_111_111_111;
#[derive(Default)]
pub struct DirectoryBlock {
entries: [[u8; 256]; 15],
inode_ids: [usize; 15],
occupancy_map: u32,
reserved: [u8; 132],
}
impl Block for DirectoryBlock {}
impl DirectoryBlock {
fn vacant(&self) -> bool {
self.occupancy_map & FULL_MAP != FULL_MAP
}
fn first_free(&self) -> Option<usize> {
todo!()
}
fn mark_busy(&mut self, entry_id: usize) {
todo!()
}
/// 需要判断 entry_name.len() <= 255
pub fn write_entry(&mut self, entry_name: &[u8], entry_inode_id: usize) -> Option<usize> {
if let Some(entry_id) = self.first_free() {
self.mark_busy(entry_id);
self.entries[entry_id].copy_from_slice(entry_name);
self.inode_ids[entry_id] = entry_inode_id;
Some(entry_id)
} else {
None
}
}
}
#[derive(Default)]
pub struct IndirectBlock {
pub entries: [u32; 1024],
}
impl Block for IndirectBlock {}
impl IndirectBlock {
pub fn full(&self) -> bool {
todo!()
}
pub fn allocate(&mut self) -> Option<usize> {
todo!()
}
}
#[derive(Default)]
pub struct DoubleIndirectBlock {
pub indirect: [u32; 1024],
}
impl Block for DoubleIndirectBlock {}
impl DoubleIndirectBlock {
pub fn full(&self) -> bool {
todo!()
}
pub fn allocate(&mut self) -> Option<usize> {
todo!()
}
}
#[derive(Default)]
pub struct TripleIndirectBlock {
pub double_indirect: [u32; 1024],
}
impl Block for TripleIndirectBlock {}
impl TripleIndirectBlock {
pub fn full(&self) -> bool {
todo!()
}
pub fn allocate(&mut self) -> Option<usize> {
todo!()
}
}
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