Struct ssdeep::internal_hashes::PartialFNVHash

pub struct PartialFNVHash(_);

Hasher which computes the lowest 6-bits of a 32-bit FNV-1 variant.

This variant of FNV-1 hash has the regular prime constant of 0x01000193 but has different initial state: 0x28021967 (in constrast to regular FNV-1-32’s 0x811c9dc5).

Since ssdeep only uses the lowest 6-bits of the hash value, it ignores any higher bits, enabling update method table-based (instead of multiply and xor) unless opt-reduce-fnv-table feature is enabled.

Implementations

impl PartialFNVHash

pub fn new() -> Self

Creates a new PartialFNVHash with the initial value.

pub fn update_by_byte(&mut self, ch: u8) -> &mut Self

Updates the hash value by processing a byte.

pub fn update_by_iter(&mut self, iter: impl Iterator<Item = u8>) -> &mut Self

Updates the hash value by processing an iterator of u8.

pub fn update(&mut self, buf: &[u8]) -> &mut Self

Updates the hash value by processing a slice of u8.

pub fn value(&self) -> u8

Returns the current hash value.

Note that there’s no “finalization” on the FNV hash. You can even continue updating after reading the hash value.

Trait Implementations

impl Clone for PartialFNVHash

fn clone(&self) -> PartialFNVHash

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for PartialFNVHash

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

Formats the value using the given formatter.

impl Default for PartialFNVHash

fn default() -> Self

Returns the “default value” for a type.

impl PartialEq<PartialFNVHash> for PartialFNVHash

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

This method tests for self and other values to be equal, and is used by ==.

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

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

impl Copy for PartialFNVHash

impl Eq for PartialFNVHash

impl StructuralEq for PartialFNVHash

impl StructuralPartialEq for PartialFNVHash