Struct ExtendedAttribute 

pub struct ExtendedAttribute {
    pub name: String,
    pub index: u8,
    pub value: Vec<u8>,
}

A single extended attribute, with the name already compressed (prefix stripped) for on-disk storage.

Fields

name: String

The name with its prefix stripped (the “suffix”).

index: u8

Prefix index (see XATTR_PREFIXES).

value: Vec<u8>

Raw attribute value.

Implementations

impl ExtendedAttribute

pub fn new(full_name: &str, value: Vec<u8>) -> Self

Create from a full attribute name (e.g. “user.mime_type”) and value. The name is automatically compressed by finding the longest matching prefix.

pub fn compress_name(name: &str) -> (u8, String)

Compress an attribute name by finding the longest matching prefix. Returns (prefix_index, suffix). If no prefix matches, index 0 is returned and the full name is kept.

pub fn decompress_name(index: u8, suffix: &str) -> String

Reconstruct the full attribute name from a prefix index and suffix.

pub fn entry_size(&self) -> u32

On-disk size of the entry header + name (aligned to 4 bytes). The entry header (XAttrEntry) is 16 bytes.

pub fn value_size(&self) -> u32

On-disk size of the value (aligned to 4 bytes).

pub fn total_size(&self) -> u32

Total on-disk footprint: entry + value.

pub fn hash(&self) -> u32

Compute the ext4 xattr hash for this attribute.

The hash covers the name (byte-by-byte mixed into a rolling hash) and the value (word-by-word). This matches the kernel’s ext4_xattr_hash_entry algorithm.

Trait Implementations

impl Clone for ExtendedAttribute

fn clone(&self) -> ExtendedAttribute

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ExtendedAttribute

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

Formats the value using the given formatter.