Struct InMemoryStorage 

pub struct InMemoryStorage { /* private fields */ }

Available on crate feature vfs only.

In-memory VFS storage implementation.

Stores files and directories in memory using HashMap and HashSet. Thread-safe via a single RwLock over the combined state.

Total file content is capped at DEFAULT_MAX_BYTES unless changed with InMemoryStorage::with_max_bytes; operations that would exceed the cap fail with VfsError::QuotaExceeded, which guests see as ENOSPC.

Implementations

impl InMemoryStorage

pub fn new() -> InMemoryStorage

Create a new empty in-memory storage with root directory.

Total file content is capped at DEFAULT_MAX_BYTES.

pub fn with_max_bytes(max_bytes: u64) -> InMemoryStorage

Create a new empty in-memory storage with an explicit size cap.

max_bytes bounds the total content of all files combined. Because the contents live in host memory and a sandboxed guest picks its own write offsets, this is a limit on how much memory the guest can make the host allocate - keep it well below what the host can afford to lose.

pub fn max_bytes(&self) -> u64

The total-content cap, in bytes.

pub async fn snapshot(&self) -> InMemorySnapshot

Capture the entire contents (files and directories) as a snapshot.

The snapshot is an independent copy; later mutations to this storage do not affect it.

pub async fn restore(&self, snapshot: &InMemorySnapshot)

Replace this storage’s entire contents with a snapshot, in place.

The storage’s identity is preserved, so any Arc<dyn VfsStorage> handles (e.g. those wired into a running sandbox) continue to refer to it and see the restored contents.

pub fn from_snapshot(snapshot: &InMemorySnapshot) -> InMemoryStorage

Create a new, independent storage initialized from a snapshot.

Useful for forking a session: the returned storage shares no state with the original, so the two can diverge freely.

Trait Implementations

impl Debug for InMemoryStorage

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Default for InMemoryStorage

fn default() -> InMemoryStorage

Returns the “default value” for a type.

impl VfsStorage for InMemoryStorage

fn as_any(&self) -> Option<&(dyn Any + 'static)>

Downcasting hook for storage-specific operations (e.g. capturing an in-memory snapshot).

fn read<'life0, 'life1, 'async_trait>( &'life0 self, path: &'life1 str, ) -> Pin<Box<dyn Future<Output = Result<Vec<u8>, VfsError>> + Send + 'async_trait>>

where 'life0: 'async_trait, 'life1: 'async_trait, InMemoryStorage: 'async_trait,

Read file contents.

fn read_at<'life0, 'life1, 'async_trait>( &'life0 self, path: &'life1 str, offset: u64, len: u64, ) -> Pin<Box<dyn Future<Output = Result<Vec<u8>, VfsError>> + Send + 'async_trait>>

where 'life0: 'async_trait, 'life1: 'async_trait, InMemoryStorage: 'async_trait,

Read a portion of file contents.

fn write<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, path: &'life1 str, data: &'life2 [u8], ) -> Pin<Box<dyn Future<Output = Result<(), VfsError>> + Send + 'async_trait>>

where 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait, InMemoryStorage: 'async_trait,

Write file contents (creates or overwrites).

fn write_at<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, path: &'life1 str, offset: u64, data: &'life2 [u8], ) -> Pin<Box<dyn Future<Output = Result<(), VfsError>> + Send + 'async_trait>>

where 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait, InMemoryStorage: 'async_trait,

Write at a specific offset, extending the file if necessary.

fn set_size<'life0, 'life1, 'async_trait>( &'life0 self, path: &'life1 str, size: u64, ) -> Pin<Box<dyn Future<Output = Result<(), VfsError>> + Send + 'async_trait>>

where 'life0: 'async_trait, 'life1: 'async_trait, InMemoryStorage: 'async_trait,

Truncate or extend file to the given size.

fn delete<'life0, 'life1, 'async_trait>( &'life0 self, path: &'life1 str, ) -> Pin<Box<dyn Future<Output = Result<(), VfsError>> + Send + 'async_trait>>

where 'life0: 'async_trait, 'life1: 'async_trait, InMemoryStorage: 'async_trait,

Delete a file.

fn exists<'life0, 'life1, 'async_trait>( &'life0 self, path: &'life1 str, ) -> Pin<Box<dyn Future<Output = Result<bool, VfsError>> + Send + 'async_trait>>

where 'life0: 'async_trait, 'life1: 'async_trait, InMemoryStorage: 'async_trait,

Check if a path exists.

fn list<'life0, 'life1, 'async_trait>( &'life0 self, path: &'life1 str, ) -> Pin<Box<dyn Future<Output = Result<Vec<DirEntry>, VfsError>> + Send + 'async_trait>>

where 'life0: 'async_trait, 'life1: 'async_trait, InMemoryStorage: 'async_trait,

List directory contents.

fn stat<'life0, 'life1, 'async_trait>( &'life0 self, path: &'life1 str, ) -> Pin<Box<dyn Future<Output = Result<Metadata, VfsError>> + Send + 'async_trait>>

where 'life0: 'async_trait, 'life1: 'async_trait, InMemoryStorage: 'async_trait,

Get file/directory metadata.

fn mkdir<'life0, 'life1, 'async_trait>( &'life0 self, path: &'life1 str, ) -> Pin<Box<dyn Future<Output = Result<(), VfsError>> + Send + 'async_trait>>

where 'life0: 'async_trait, 'life1: 'async_trait, InMemoryStorage: 'async_trait,

Create a directory.

fn rmdir<'life0, 'life1, 'async_trait>( &'life0 self, path: &'life1 str, ) -> Pin<Box<dyn Future<Output = Result<(), VfsError>> + Send + 'async_trait>>

where 'life0: 'async_trait, 'life1: 'async_trait, InMemoryStorage: 'async_trait,

Remove a directory (must be empty).

fn rename<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, from: &'life1 str, to: &'life2 str, ) -> Pin<Box<dyn Future<Output = Result<(), VfsError>> + Send + 'async_trait>>

where 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait, InMemoryStorage: 'async_trait,

Rename/move a file or directory.

fn mkdir_sync(&self, path: &str) -> Result<(), VfsError>

Synchronously create a directory.