Struct RegularFile 

pub struct RegularFile(pub Arc<dyn RegularFile>);

A handle to a regular file.

This struct provides a reference-counted handle to a file that supports reading and writing operations at the kernel level.

Tuple Fields

0: Arc<dyn RegularFile>

Implementations

impl RegularFile

pub fn ino(&self) -> InodeNumber

Inode number of the file.

pub fn new(r: impl RegularFile + 'static) -> Self

Creates a new RegularFile handle from a given implementation of traits::RegularFile.

This function takes an instance of any type that implements the traits::RegularFile trait, wraps it in a reference-counted [Arc], and returns a RegularFile handle.

Parameters

• r: An instance of a type that implements traits::RegularFile.

Returns

A RegularFile handle that enables reference-counted access to the underlying file.

pub fn size(&self) -> usize

Returns the size of the file in bytes.

pub fn read( &self, position: usize, buf: &mut [u8], ) -> Result<usize, KernelError>

Reads data from the file into the provided buffer.

Parameters

• fba: The FileBlockNumber which to read.
• buf: A mutable slice where the file content will be stored.

Returns

• Ok(usize): The number of bytes read.
• Err(Error): An error if the read operation fails.

pub fn write(&self, position: usize, buf: &[u8]) -> Result<usize, KernelError>

Writes data from the buffer into the file.

If the write position is beyond the current file size, file will be extended to minimum size required to reflect the update.

Parameters

• fba: The FileBlockNumber which to write.
• buf: An slice containing the data to write.

Returns

• Ok(usize): The number of bytes written.
• Err(Error): An error if the write operation fails.

pub fn mmap(&self, fba: FileBlockNumber) -> Result<Page, KernelError>

Maps a file block into memory.

This method retrieves the contents of the file at the specified file block number (fba) and returns it as a Page of the file block.

The memory-mapped page reflects the current contents of the file at the requested block, and it can be used for reading or modifying file data at page granularity.

Parameters

• fba: The file block number to map into memory. This is a logical offset into the file, measured in fixed-size blocks (not bytes).

Returns

• Ok(Page): A reference-counted, in-memory page containing the file block’s data.
• Err(KernelError): If the file block cannot be found or loaded (e.g., out-of-bounds access).

pub fn writeback(&self) -> Result<(), KernelError>

Write back the file to disk.

Trait Implementations

impl Clone for RegularFile

fn clone(&self) -> RegularFile

Returns a duplicate of the value.

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

Performs copy-assignment from source.