Struct SessionUsabilityRequirements

pub struct SessionUsabilityRequirements(/* private fields */);

Specifies which criteria make a session “usable” beyond simply having a present sender chain.

These requirements are conjunctive, i.e. specifying NotStale | EstablishedWithPqxdh means the session must be neither stale nor established with X3DH.

This struct is generated using the bitflags crate; the Flags trait provides most of its API surface. It can also use “classic” C bitflag syntax, with | for union and & for intersection (as shown above).

Implementations

impl SessionUsabilityRequirements

pub const NotStale: Self

Requires that a session not be stale.

A non-stale session is one of the following:

• “incoming”, i.e. started by the peer
• “acknowledged”, i.e. started locally but received a response
• no more than a few weeks old (the exact time is chosen by libsignal)

pub const EstablishedWithPqxdh: Self

Requires that a session was established using PQXDH (or newer) rather than X3DH/X4DH.

This includes unacknowledged sessions that are using PQXDH, since if they get a response, the peer is confirmed to be using PQXDH as well.

pub const Spqr: Self

Requires that a session is using SPQR.

Warning: This allows unacknowledged sessions that include SPQR in their PreKey messages. If the peer downgrades the session (by discarding the SPQR information) and the local client allows it, a session that is previously considered “usable” can become “not usable” upon receiving a response. Therefore, this should not be used to determine whether a session is usable unless future downgrades will also be rejected.

impl SessionUsabilityRequirements

pub const fn empty() -> Self

Get a flags value with all bits unset.

pub const fn all() -> Self

Get a flags value with all known bits set.

pub const fn bits(&self) -> u32

Get the underlying bits value.

The returned value is exactly the bits set in this flags value.

pub const fn from_bits(bits: u32) -> Option<Self>

Convert from a bits value.

This method will return None if any unknown bits are set.

pub const fn from_bits_truncate(bits: u32) -> Self

Convert from a bits value, unsetting any unknown bits.

pub const fn from_bits_retain(bits: u32) -> Self

Convert from a bits value exactly.

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

Get a flags value with the bits of a flag with the given name set.

This method will return None if name is empty or doesn’t correspond to any named flag.

pub const fn is_empty(&self) -> bool

Whether all bits in this flags value are unset.

pub const fn is_all(&self) -> bool

Whether all known bits in this flags value are set.

pub const fn intersects(&self, other: Self) -> bool

Whether any set bits in a source flags value are also set in a target flags value.

pub const fn contains(&self, other: Self) -> bool

Whether all set bits in a source flags value are also set in a target flags value.

pub fn insert(&mut self, other: Self)

The bitwise or (|) of the bits in two flags values.

pub fn remove(&mut self, other: Self)

The intersection of a source flags value with the complement of a target flags value (&!).

This method is not equivalent to self & !other when other has unknown bits set. remove won’t truncate other, but the ! operator will.

pub fn toggle(&mut self, other: Self)

The bitwise exclusive-or (^) of the bits in two flags values.

pub fn set(&mut self, other: Self, value: bool)

Call insert when value is true or remove when value is false.

pub const fn intersection(self, other: Self) -> Self

The bitwise and (&) of the bits in two flags values.

pub const fn union(self, other: Self) -> Self

The bitwise or (|) of the bits in two flags values.

pub const fn difference(self, other: Self) -> Self

The intersection of a source flags value with the complement of a target flags value (&!).

This method is not equivalent to self & !other when other has unknown bits set. difference won’t truncate other, but the ! operator will.

pub const fn symmetric_difference(self, other: Self) -> Self

The bitwise exclusive-or (^) of the bits in two flags values.

pub const fn complement(self) -> Self

The bitwise negation (!) of the bits in a flags value, truncating the result.

impl SessionUsabilityRequirements

pub const fn iter(&self) -> Iter<SessionUsabilityRequirements>

Yield a set of contained flags values.

Each yielded flags value will correspond to a defined named flag. Any unknown bits will be yielded together as a final flags value.

pub const fn iter_names(&self) -> IterNames<SessionUsabilityRequirements>

Yield a set of contained named flags values.

This method is like iter, except only yields bits in contained named flags. Any unknown bits, or bits not corresponding to a contained flag will not be yielded.

Trait Implementations

impl Binary for SessionUsabilityRequirements

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

Formats the value using the given formatter.

impl BitAnd for SessionUsabilityRequirements

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

The bitwise and (&) of the bits in two flags values.

type Output = SessionUsabilityRequirements

The resulting type after applying the & operator.

impl BitAndAssign for SessionUsabilityRequirements

fn bitand_assign(&mut self, other: Self)

The bitwise and (&) of the bits in two flags values.

impl BitOr for SessionUsabilityRequirements

fn bitor(self, other: SessionUsabilityRequirements) -> Self

The bitwise or (|) of the bits in two flags values.

type Output = SessionUsabilityRequirements

The resulting type after applying the | operator.

impl BitOrAssign for SessionUsabilityRequirements

fn bitor_assign(&mut self, other: Self)

The bitwise or (|) of the bits in two flags values.

impl BitXor for SessionUsabilityRequirements

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

The bitwise exclusive-or (^) of the bits in two flags values.

type Output = SessionUsabilityRequirements

The resulting type after applying the ^ operator.

impl BitXorAssign for SessionUsabilityRequirements

fn bitxor_assign(&mut self, other: Self)

The bitwise exclusive-or (^) of the bits in two flags values.

impl Clone for SessionUsabilityRequirements

fn clone(&self) -> SessionUsabilityRequirements

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Extend<SessionUsabilityRequirements> for SessionUsabilityRequirements

fn extend<T: IntoIterator<Item = Self>>(&mut self, iterator: T)

The bitwise or (|) of the bits in each flags value.

fn extend_one(&mut self, item: A)

🔬This is a nightly-only experimental API. (extend_one)

Extends a collection with exactly one element.

fn extend_reserve(&mut self, additional: usize)

🔬This is a nightly-only experimental API. (extend_one)

Reserves capacity in a collection for the given number of additional elements.

impl Flags for SessionUsabilityRequirements

const FLAGS: &'static [Flag<SessionUsabilityRequirements>]

The set of defined flags.

type Bits = u32

The underlying bits type.

fn bits(&self) -> u32

Get the underlying bits value.

fn from_bits_retain(bits: u32) -> SessionUsabilityRequirements

Convert from a bits value exactly.

fn empty() -> Self

Get a flags value with all bits unset.

fn all() -> Self

Get a flags value with all known bits set.

fn contains_unknown_bits(&self) -> bool

This method will return true if any unknown bits are set.

fn from_bits(bits: Self::Bits) -> Option<Self>

Convert from a bits value.

fn from_bits_truncate(bits: Self::Bits) -> Self

Convert from a bits value, unsetting any unknown bits.

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

Get a flags value with the bits of a flag with the given name set.

fn iter(&self) -> Iter<Self>

Yield a set of contained flags values.

fn iter_names(&self) -> IterNames<Self>

Yield a set of contained named flags values.

fn is_empty(&self) -> bool

Whether all bits in this flags value are unset.

fn is_all(&self) -> bool

Whether all known bits in this flags value are set.

fn intersects(&self, other: Self) -> bool

where Self: Sized,

Whether any set bits in a source flags value are also set in a target flags value.

fn contains(&self, other: Self) -> bool

where Self: Sized,

Whether all set bits in a source flags value are also set in a target flags value.

fn truncate(&mut self)

where Self: Sized,

Remove any unknown bits from the flags.

fn insert(&mut self, other: Self)

where Self: Sized,

The bitwise or (|) of the bits in two flags values.

fn remove(&mut self, other: Self)

where Self: Sized,

The intersection of a source flags value with the complement of a target flags value (&!).

fn toggle(&mut self, other: Self)

where Self: Sized,

The bitwise exclusive-or (^) of the bits in two flags values.

fn set(&mut self, other: Self, value: bool)

where Self: Sized,

Call [Flags::insert] when value is true or [Flags::remove] when value is false.

fn clear(&mut self)

where Self: Sized,

Unsets all bits in the flags.

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

The bitwise and (&) of the bits in two flags values.

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

The bitwise or (|) of the bits in two flags values.

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

The intersection of a source flags value with the complement of a target flags value (&!).

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

The bitwise exclusive-or (^) of the bits in two flags values.

fn complement(self) -> Self

The bitwise negation (!) of the bits in a flags value, truncating the result.

impl FromIterator<SessionUsabilityRequirements> for SessionUsabilityRequirements

fn from_iter<T: IntoIterator<Item = Self>>(iterator: T) -> Self

The bitwise or (|) of the bits in each flags value.

impl IntoIterator for SessionUsabilityRequirements

type Item = SessionUsabilityRequirements

The type of the elements being iterated over.

type IntoIter = Iter<SessionUsabilityRequirements>

Which kind of iterator are we turning this into?

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

impl LowerHex for SessionUsabilityRequirements

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

Formats the value using the given formatter.

impl Not for SessionUsabilityRequirements

fn not(self) -> Self

The bitwise negation (!) of the bits in a flags value, truncating the result.

type Output = SessionUsabilityRequirements

The resulting type after applying the ! operator.

impl Octal for SessionUsabilityRequirements

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

Formats the value using the given formatter.

impl PartialEq for SessionUsabilityRequirements

fn eq(&self, other: &SessionUsabilityRequirements) -> 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 PublicFlags for SessionUsabilityRequirements

type Primitive = u32

The type of the underlying storage.

type Internal = InternalBitFlags

The type of the internal field on the generated flags type.

impl Sub for SessionUsabilityRequirements

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

The intersection of a source flags value with the complement of a target flags value (&!).

This method is not equivalent to self & !other when other has unknown bits set. difference won’t truncate other, but the ! operator will.

type Output = SessionUsabilityRequirements

The resulting type after applying the - operator.

impl SubAssign for SessionUsabilityRequirements

fn sub_assign(&mut self, other: Self)

The intersection of a source flags value with the complement of a target flags value (&!).

This method is not equivalent to self & !other when other has unknown bits set. difference won’t truncate other, but the ! operator will.

impl UpperHex for SessionUsabilityRequirements

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

Formats the value using the given formatter.

impl Copy for SessionUsabilityRequirements

impl Eq for SessionUsabilityRequirements

impl StructuralPartialEq for SessionUsabilityRequirements