Struct LongFileName 

pub struct LongFileName { /* private fields */ }

A Long File Name stored as UTF-16.

LFN entries on disk encode the filename in UTF-16LE. Storing the data in its native form avoids two classes of bugs that previously lived here (see issue #28): the buffer never holds invalid UTF-8, and surrogate pairs (characters outside the Basic Multilingual Plane, e.g. emoji) are preserved correctly regardless of how the pair lands across LFN entry boundaries — the conversion to scalar values happens once, at access time.

Implementations

impl LongFileName

pub const CHARS_PER_ENTRY: usize = 13

Number of UTF-16 code units stored per LFN directory entry

pub fn new() -> Self

Create a new empty LongFileName

pub fn clear(&mut self)

Clear the filename

pub fn is_empty(&self) -> bool

Check if the filename is empty

pub fn len(&self) -> usize

Number of UTF-16 code units in the filename.

pub fn prepend_lfn_entry( &mut self, name1: &[u8; 10], name2: &[u8; 12], name3: &[u8; 4], )

Prepend UTF-16LE characters from an LFN entry. LFN entries are stored in reverse order, so we prepend. Characters are: 5 from name1, 6 from name2, 2 from name3.

pub fn as_utf16(&self) -> &[u16]

Borrow the filename as raw UTF-16 code units.

pub fn chars(&self) -> impl Iterator<Item = char> + '_

Iterate over the decoded scalar values of the filename.

Lone surrogates (which the spec disallows but a malformed image could contain) are reported as char::REPLACEMENT_CHARACTER (U+FFFD).

pub fn eq_str(&self, s: &str) -> bool

Compare the filename to a &str without allocating.

pub fn from_str_utf16(name: &str) -> Option<Self>

Encode name as UTF-16LE into the buffer. Returns None if the name exceeds LFN_MAX_UTF16_UNITS (the FAT spec cap for LFN names). Used by the write path to remember the name in-memory after creating a file; the chars stay in UTF-16 so the disk-side LFN write can pull them out without a second UTF-8 conversion.

Trait Implementations

impl Clone for LongFileName

fn clone(&self) -> LongFileName

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for LongFileName

Available on crate feature lfn only.

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

Formats the value using the given formatter.

impl Default for LongFileName

Available on crate feature lfn only.

fn default() -> Self

Returns the “default value” for a type.

impl Display for LongFileName

Available on crate feature lfn only.

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

Formats the value using the given formatter.

impl Eq for LongFileName

impl PartialEq for LongFileName

fn eq(&self, other: &LongFileName) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for LongFileName