Enum Opcode 

#[non_exhaustive]
pub enum Opcode {
    Query,
    InverseQuery,
    Status,
    Notify,
    Update,
    Unknown(u8),
}

DNS message opcode. mDNS requires Opcode::Query (0); other values are kept for round-trip correctness against non-conforming traffic.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Query

Standard query (0).

InverseQuery

Inverse query (1, obsoleted by RFC 3425).

Status

Server status request (2).

Notify

Notify (4, RFC 1996).

Update

Dynamic update (5, RFC 2136).

Unknown(u8)

Lossless escape for unknown opcodes encountered on the wire.

Implementations

impl Opcode

pub const fn is_query(&self) -> bool

Returns true if this value is of type Query. Returns false otherwise

pub const fn is_inverse_query(&self) -> bool

Returns true if this value is of type InverseQuery. Returns false otherwise

pub const fn is_status(&self) -> bool

Returns true if this value is of type Status. Returns false otherwise

pub const fn is_notify(&self) -> bool

Returns true if this value is of type Notify. Returns false otherwise

pub const fn is_update(&self) -> bool

Returns true if this value is of type Update. Returns false otherwise

pub const fn is_unknown(&self) -> bool

Returns true if this value is of type Unknown. Returns false otherwise

impl Opcode

pub fn unwrap_query(self)

Unwraps this value to the Opcode::Query variant. Panics if this value is of any other type.

pub fn unwrap_inverse_query(self)

Unwraps this value to the Opcode::InverseQuery variant. Panics if this value is of any other type.

pub fn unwrap_status(self)

Unwraps this value to the Opcode::Status variant. Panics if this value is of any other type.

pub fn unwrap_notify(self)

Unwraps this value to the Opcode::Notify variant. Panics if this value is of any other type.

pub fn unwrap_update(self)

Unwraps this value to the Opcode::Update variant. Panics if this value is of any other type.

pub fn unwrap_unknown(self) -> u8

Unwraps this value to the Opcode::Unknown variant. Panics if this value is of any other type.

impl Opcode

pub fn try_unwrap_query(self) -> Result<(), TryUnwrapError<Self>>

Attempts to unwrap this value to the Opcode::Query variant. Returns a [TryUnwrapError] with the original value if this value is of any other type.

pub fn try_unwrap_inverse_query(self) -> Result<(), TryUnwrapError<Self>>

Attempts to unwrap this value to the Opcode::InverseQuery variant. Returns a [TryUnwrapError] with the original value if this value is of any other type.

pub fn try_unwrap_status(self) -> Result<(), TryUnwrapError<Self>>

Attempts to unwrap this value to the Opcode::Status variant. Returns a [TryUnwrapError] with the original value if this value is of any other type.

pub fn try_unwrap_notify(self) -> Result<(), TryUnwrapError<Self>>

Attempts to unwrap this value to the Opcode::Notify variant. Returns a [TryUnwrapError] with the original value if this value is of any other type.

pub fn try_unwrap_update(self) -> Result<(), TryUnwrapError<Self>>

Attempts to unwrap this value to the Opcode::Update variant. Returns a [TryUnwrapError] with the original value if this value is of any other type.

pub fn try_unwrap_unknown(self) -> Result<u8, TryUnwrapError<Self>>

Attempts to unwrap this value to the Opcode::Unknown variant. Returns a [TryUnwrapError] with the original value if this value is of any other type.

impl Opcode

pub const fn as_str(&self) -> &'static str

Canonical lowercase slug for this opcode.

pub const fn to_u8(self) -> u8

Returns the wire-format u8 value (only the low 4 bits are significant in the actual flags field, but the conversion is total for u8).

pub const fn from_u8(v: u8) -> Self

Reconstructs an Opcode from a wire-format u8. Always succeeds — unknown values land in Unknown(v).

Trait Implementations

impl Clone for Opcode

fn clone(&self) -> Opcode

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for Opcode

impl Debug for Opcode

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

Formats the value using the given formatter.

impl Display for Opcode

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

Formats the value using the given formatter.

impl Eq for Opcode

impl Hash for Opcode

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 Ord for Opcode

fn cmp(&self, other: &Opcode) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for Opcode

fn eq(&self, other: &Opcode) -> 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 PartialOrd for Opcode

fn partial_cmp(&self, other: &Opcode) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

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

Tests less than (for self and other) and is used by the < operator.

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

Tests less than or equal to (for self and other) and is used by the <= operator.

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

Tests greater than (for self and other) and is used by the > operator.

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

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl StructuralPartialEq for Opcode