Struct FileSizing 

pub struct FileSizing {
    pub logical: u64,
    pub allocated: u64,
    pub unique: Option<u64>,
    pub sharing: Sharing,
    pub inode: InodeId,
    pub nlink: u64,
    pub clone_id: Option<u64>,
    pub clone_refcount: Option<u32>,
}

What one file costs, and what dies with it.

Fields

logical: u64

Logical length (st_size / ATTR_FILE_DATALENGTH).

allocated: u64

Allocated bytes, counting shared blocks in full. On platforms without allocation metadata the fallback uses logical length as an estimate.

unique: Option<u64>

Bytes private to this inode. Unlinking one of several hardlinks does not free them; callers must also account for nlink. None when unsupported.

sharing: Sharing

inode: InodeId

nlink: u64

clone_id: Option<u64>

Identifies the clone group this file’s blocks belong to, when the platform reports one. IDs are scoped to inode.dev and to the observation; they are not durable content identities.

clone_refcount: Option<u32>

Live inodes in this file’s clone group, itself included, when the platform reports it (APFS ATTR_CMNEXT_CLONE_REFCNT). At most one means no other file shares these blocks: whatever is not private is held by filesystem snapshots, and is freed once those snapshots go.

Implementations

impl FileSizing

pub fn shared(&self) -> Option<u64>

Blocks shared with other inodes, when known.

pub fn snapshot_held(&self) -> Option<u64>

Shared bytes that no other live file holds, only snapshots. None when the platform does not report the clone group’s size, or when the group’s size cannot tell a snapshot from a live file.

APFS counts only the files still in an unmodified clone group. A clone that is written to leaves the group and gets a new clone id, while it keeps sharing every block it did not rewrite. Partly rewriting a clone therefore leaves both files partly shared with a refcount of 1 each. A store blob is never written after it is stored, so a blob that is partly shared was partly rewritten through a live clone, and its shared bytes stay unknown. Appending to a clone leaves the blob fully shared with a refcount of 1, which reads the same as a snapshot and is counted as one (kunobi-ninja/kache#1195).

pub fn frees_nothing(&self) -> bool

True when deleting this file alone reclaims nothing.

Trait Implementations

impl Clone for FileSizing

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for FileSizing

impl Debug for FileSizing

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

Formats the value using the given formatter.