Struct HtonCapabilities 

#[non_exhaustive]
pub struct HtonCapabilities(/* private fields */);

The set of engine-level features a Handlerton opts into.

Each capability gates a group of handlerton callbacks. A group will be wired into the handlerton struct only when its bit is set here, because MySQL reads a non-NULL function pointer as a declaration that the engine supports that feature — a non-NULL commit, for example, marks the engine transactional. Declaring a capability the engine does not implement would route work to callbacks that cannot honour it, so default to the smallest set that is actually backed by code.

Combine capabilities with |:

use mysql_handler::hton::HtonCapabilities;

let caps = HtonCapabilities::TRANSACTIONS | HtonCapabilities::SAVEPOINTS;
assert!(caps.contains(HtonCapabilities::TRANSACTIONS));
assert!(!caps.contains(HtonCapabilities::XA));

Implementations

impl HtonCapabilities

pub const TRANSACTIONS: Self

Transaction callbacks (commit, rollback, prepare)

pub const XA: Self

XA / 2PC recovery callbacks (recover, commit_by_xid, …)

pub const SAVEPOINTS: Self

Savepoint callbacks (savepoint_set, savepoint_rollback, …)

pub const SDI: Self

Serialized Dictionary Information callbacks (sdi_*)

pub const SECONDARY_ENGINE: Self

Secondary-engine callbacks (prepare_secondary_engine, …)

pub const CLONE: Self

Clone-interface sub-callbacks

pub const PAGE_TRACKING: Self

Page-tracking sub-callbacks

pub const PARTITIONING: Self

Partitioning support: gates the partition_flags accessor on the handlerton. A non-NULL partition_flags pointer signals MySQL that the engine implements handler::get_partition_handler, so this must stay off for a non-partitioning engine.

pub const TABLESPACES: Self

Tablespace ownership: gates the tablespace callbacks (get_tablespace, alter_tablespace, upgrade_tablespace, …). Non-NULL pointers tell MySQL the engine owns tablespaces (InnoDB-style); leave off for a tablespace-less engine to keep MySQL from routing tablespace work here.

pub const DICT_BACKEND: Self

Data-dictionary backend: gates the dict_* callbacks. A non-DD-backend engine (anything other than the DD storage backend itself) must keep these unwired, otherwise MySQL routes dictionary work to an engine that cannot honour it.

pub const ENGINE_LOG: Self

Engine-owned redo / transaction log: gates lock_hton_log, unlock_hton_log, collect_hton_log_info, and redo_log_set_state. Declared by engines whose log is collected by performance_schema.log_status.

pub const ENCRYPTION: Self

Encryption support: gates rotate_encryption_master_key. Non-NULL signals MySQL that the engine participates in master-key rotation, so leave it off for a non-encrypting engine.

pub const fn empty() -> Self

An empty capability set: a handler-only engine (the zero-config default)

pub const fn bits(self) -> u32

The raw bits, for handing the set across the FFI boundary

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

Whether every capability in other is present in self

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

The union of two capability sets

Trait Implementations

impl BitOr for HtonCapabilities

type Output = HtonCapabilities

The resulting type after applying the | operator.

fn bitor(self, rhs: Self) -> Self

Performs the | operation.

impl Clone for HtonCapabilities

fn clone(&self) -> HtonCapabilities

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for HtonCapabilities

impl Debug for HtonCapabilities

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

Formats the value using the given formatter.

impl Eq for HtonCapabilities

impl PartialEq for HtonCapabilities

fn eq(&self, other: &HtonCapabilities) -> 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 StructuralPartialEq for HtonCapabilities