Struct TmpFS

pub struct TmpFS {
    root: RwLock<Arc<TmpNode>>,
    memory_limit: usize,
    current_memory: Mutex<usize>,
    next_file_id: Mutex<u64>,
    name: String,
}

TmpFS v2 - New memory-based filesystem implementation

This struct implements an in-memory filesystem for VFS v2. It supports regular files, directories, and device nodes, with optional memory usage limits. The internal structure is based on TmpNode and uses locking for thread safety.

Fields

root: RwLock<Arc<TmpNode>>

Root directory node

memory_limit: usize

Memory limit (0 = unlimited)

current_memory: Mutex<usize>

Current memory usage

next_file_id: Mutex<u64>

Next file ID generator

name: String

Filesystem name

Implementations

impl TmpFS

pub fn new(memory_limit: usize) -> Arc<Self>

Create a new TmpFS instance (two-phase initialization)

pub fn create_from_option_string( option: Option<&str>, ) -> Arc<dyn FileSystemOperations>

VFS v2 driver registration API: create from option string Example option: “mem=1048576” etc.

fn generate_file_id(&self) -> u64

Generate next unique file ID

fn check_memory_limit( &self, additional_bytes: usize, ) -> Result<(), FileSystemError>

Check memory limit

fn add_memory_usage(&self, bytes: usize)

Add to memory usage

fn subtract_memory_usage(&self, bytes: usize)

Subtract from memory usage

Trait Implementations

impl FileSystemOperations for TmpFS

fn create_hardlink( &self, link_parent: &Arc<dyn VfsNode>, link_name: &String, target_node: &Arc<dyn VfsNode>, ) -> Result<Arc<dyn VfsNode>, FileSystemError>

Create a hard link to an existing file

This function creates a new directory entry (hard link) for an existing file. Both the link and the target must be in the same filesystem. The link count of the target file is incremented. Returns the target node (the same inode as the original file).

fn lookup( &self, parent_node: &Arc<dyn VfsNode>, name: &String, ) -> Result<Arc<dyn VfsNode>, FileSystemError>

Look up a child node by name within a parent directory

fn open( &self, node: &Arc<dyn VfsNode>, _flags: u32, ) -> Result<Arc<dyn FileObject>, FileSystemError>

Open a file represented by a VfsNode

fn create( &self, parent_node: &Arc<dyn VfsNode>, name: &String, file_type: FileType, _mode: u32, ) -> Result<Arc<dyn VfsNode>, FileSystemError>

Create a new file in the specified directory

fn remove( &self, parent_node: &Arc<dyn VfsNode>, name: &String, ) -> Result<(), FileSystemError>

Remove a file from the specified directory

fn readdir( &self, node: &Arc<dyn VfsNode>, ) -> Result<Vec<DirectoryEntryInternal>, FileSystemError>

Read directory entries from a directory node

fn root_node(&self) -> Arc<dyn VfsNode>

Get the root VfsNode for this filesystem

fn name(&self) -> &str

Get filesystem name

fn is_read_only(&self) -> bool

Check if filesystem is read-only