Enum DhtArc

pub enum DhtArc {
    Empty,
    Arc(u32, u32),
}

The definition of a storage arc compatible with the concept of storage and querying of items in a store that fall within that arc.

Variants

Empty

No DHT locations are contained within this arc.

Arc(u32, u32)

A specific range of DHT locations are contained within this arc.

The lower and upper bounds are inclusive.

Implementations

impl DhtArc

pub const FULL: DhtArc

A full arc that contains all DHT locations.

pub fn dist(&self, loc: u32) -> u32

Get the min distance from a location to an arc in a wrapping u32 space. This function will only return 0 if the location is covered by the arc. This function will return u32::MAX if the arc is empty.

All possible cases:

s = arc_start
e = arc_end
l = location

Arc wraps around, loc >= arc_start

|----e-----------s--l--|
0                      u32::MAX

Arc wraps around, loc <= arc_end
|-l--e-----------s-----|
0                      u32::MAX

Arc wraps around, loc outside of arc
|----e----l------s-----|
0                      u32::MAX

Arc does not wrap around, loc inside of arc
|---------s--l---e-----|
0                      u32::MAX

Arc does not wrap around, loc < arc_start
|-----l---s------e-----|
0                      u32::MAX

Arc does not wrap around, loc > arc_end
|---------s------e--l--|
0                      u32::MAX

pub fn contains(&self, loc: u32) -> bool

Convenience function to determine if a location is contained within the arc.

Simply checks whether the distance from the location to the arc is 0.

pub fn overlaps(&self, other: &DhtArc) -> bool

Determine if any part of two arcs overlap.

All possible cases (though note the arcs can also wrap around u32::MAX):

a = a_start
A = a_end
b = b_start
B = b_end

The tail of a..A overlaps the head of b..B

|---a--b-A--B---|

The tail of b..B overlaps the head of a..A

|---b--a-B--A---|

b..B is fully contained by a..A

|---a--b-B--A---|

a..A is fully contained by b..B

|---b--a-A--B---|

pub fn len(&self) -> u32

Get the length of the arc.

pub fn is_empty(&self) -> bool

Determine if the arc is empty.

Trait Implementations

impl Clone for DhtArc

fn clone(&self) -> DhtArc

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for DhtArc

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

Formats the value using the given formatter.

impl Default for DhtArc

fn default() -> DhtArc

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for DhtArc

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Hash for DhtArc

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for DhtArc

fn eq(&self, other: &DhtArc) -> 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 Serialize for DhtArc

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl Copy for DhtArc

impl Eq for DhtArc

impl StructuralPartialEq for DhtArc