Struct FSPrefix

pub struct FSPrefix {
    pub version: u16,
    pub meta: FSMetaV1,
}

The on-disk first few bytes of the file, consisting of:

• The FILETAG
• A u16 version
• A u64 length of the FSMetaV1
• A CRC32 of the FSMetaV1
• A CRC32 of this prefix (everything from start-of-file to immediately before this point)

After this, the FSMetaV1 can be safely read and validated based on the length and CRC.

Immediately after the FSMetaV1, the payload (if any) is present.

Fields

version: u16

meta: FSMetaV1

Implementations

impl FSPrefix

pub fn prefixlen() -> usize

pub fn encode(&self) -> Result<(Bytes, Vec<u8>), Error>

Encodes self, returning the encoded prefix and meta. You probably want FSPrefix::write instead.

pub fn read<R: Read + ?Sized>(input: &mut R) -> Result<Self, Error>

Reads, precisely, the prefix and metadata from the input reader. Does not consume any of the payload.

pub fn write<W: Write>(&self, output: &mut W) -> Result<(), Error>

Precisely writes the prefix and metadata to the output. Does not emit any payload.

Trait Implementations

impl Clone for FSPrefix

fn clone(&self) -> FSPrefix

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for FSPrefix

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

Formats the value using the given formatter.

impl Default for FSPrefix

fn default() -> Self

Returns the “default value” for a type.

impl From<FSMetaV1> for FSPrefix

fn from(meta: FSMetaV1) -> Self

Converts to this type from the input type.

impl From<FSPrefix> for FSMetaV1

fn from(prefix: FSPrefix) -> Self

Converts to this type from the input type.

impl PartialEq for FSPrefix

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Eq for FSPrefix

impl StructuralPartialEq for FSPrefix