Signal< RT(Args...), MutexT >

#include <icy/signal.h>

template<typename RT, typename... Args, typename MutexT>
class Signal< RT(Args...), MutexT >

Defined in src/base/include/icy/signal.h:142

Public Methods

Return	Name	Description
`int`	`attach` const inline	Connects a `lambda` or `std::function` to the signal.
`int`	`attach` const inline	Connects a pre-constructed `SlotPtr` to the signal.
`bool`	`detach` const inline	Detaches the slot with the given ID.
`bool`	`detach` const inline	Detaches all slots associated with the given instance pointer.
`bool`	`detach` const inline	Detaches the slot whose delegate compares equal to `other->delegate`.
`void`	`detachAll` const inline	Detaches and destroys all currently attached slots.
`RT`	`emit` virtual inline	Emits the signal, invoking all live attached slots in priority order.
std::vector< `SlotPtr` >	`slots` const inline	Returns a snapshot copy of the current slot list.
`size_t`	`nslots` const inline	Returns the number of slots currently registered with this signal.
`int`	`operator+=` inline	Attaches a function; equivalent to `attach(func)`.
`int`	`operator+=` inline	Attaches a pre-constructed slot; equivalent to `attach(slot)`.
`bool`	`operator-=` inline	Detaches the slot with the given ID; equivalent to `detach(id)`.
`bool`	`operator-=` inline	Detaches all slots for the given instance; equivalent to `detach(instance)`.
`bool`	`operator-=` inline	Detaches the slot matching `slot`'s delegate; equivalent to `detach(slot)`.
	`Signal`	Defaulted constructor.
	`~Signal` inline
	`Signal` inline	Copy constructor; copies the slot list and last-assigned ID from `r`.
`Signal` &	`operator=` inline	Copy assignment operator; copies the slot list and last-assigned ID from `r`.

attach

const inline

inline int attach(Function const & func, void * instance = nullptr, int id = -1, int priority = -1) const

Defined in src/base/include/icy/signal.h:157

Connects a lambda or std::function to the signal.

Returns

The assigned slot ID, which can be passed to detach() to disconnect.

Parameters

Parameter	Type	Description
`func`	`Function` const &	The callable to invoke when the signal is emitted.
`instance`	`void *`	Optional owner pointer used for instance-based detach; pass `nullptr` if not applicable.
`id`	`int`	Explicit slot ID to assign; pass `-1` to auto-assign.
`priority`	`int`	Higher values are called first; pass `-1` for default ordering.

attach

const inline

inline int attach(SlotPtr slot) const

Defined in src/base/include/icy/signal.h:171

Connects a pre-constructed SlotPtr to the signal.

Duplicate slots (matched by delegate equality) are removed before insertion. Slots are kept sorted in descending priority order after insertion.

Returns

The assigned slot ID, which can be passed to detach() to disconnect.

Parameters

Parameter	Type	Description
`slot`	`SlotPtr`	The slot to attach. Must have a valid delegate.

Exceptions

Exception	Description
`std::logic_error`	if `slot->id` is set explicitly and already in use.

detach

const inline

inline bool detach(int id) const

Defined in src/base/include/icy/signal.h:202

Detaches the slot with the given ID.

Safe to call from within a slot's callback (the slot is marked dead before erasure).

Returns

true if a slot was found and removed; false if the ID was not found.

Parameters

Parameter	Type	Description
`id`	`int`	The slot ID returned by `attach()`.

detach

const inline

inline bool detach(const void * instance) const

Defined in src/base/include/icy/signal.h:219

Detaches all slots associated with the given instance pointer.

Useful for bulk disconnect when an object is destroyed. Matches slots by their stored instance pointer, not by delegate equality.

Returns

true if at least one slot was removed; false otherwise.

Parameters

Parameter	Type	Description
`instance`	`const void *`	The owner pointer used when the slots were attached.

detach

const inline

inline bool detach(SlotPtr other) const

Defined in src/base/include/icy/signal.h:236

Detaches the slot whose delegate compares equal to other->delegate.

Used by the slot() helper overloads and operator-= to disconnect a specific class-member or function binding by value.

Returns

true if a matching slot was found and removed; false otherwise.

Parameters

Parameter	Type	Description
`other`	`SlotPtr`	A slot whose delegate is compared against attached slots.

detachAll

const inline

inline void detachAll() const

Defined in src/base/include/icy/signal.h:249

Detaches and destroys all currently attached slots.

Each slot is marked dead before removal. After this call nslots() returns 0.

emit

virtual inline

virtual inline RT emit(Args... args)

Defined in src/base/include/icy/signal.h:283

Emits the signal, invoking all live attached slots in priority order.

For Signal<bool(...)>: iterates slots and returns true as soon as any slot returns true, stopping further propagation. Returns false if no slot handled the event.

For Signal<void(...)>: calls every live slot unconditionally.

Local Signal<...> traverses the stable slot list directly without any snapshot allocation. ThreadSignal<...> snapshots raw node pointers under a shared lock, then invokes delegates without holding the lock. Dead slots are swept after the outermost emission returns, allowing attach/detach inside callbacks without copying shared_ptrs on the hot path.

Returns

For bool return type: true if any slot handled the event, false otherwise. For void return type: nothing.

Parameters

Parameter	Type	Description
`args`	`Args...`	Arguments forwarded to each connected slot.

slots

const inline

inline std::vector< SlotPtr > slots() const

Defined in src/base/include/icy/signal.h:350

Returns a snapshot copy of the current slot list.

The copy is taken under a shared lock, so it is safe to call concurrently with attach/detach operations. Only currently live slots are returned.

Returns

A vector of SlotPtr representing all currently registered slots.

nslots

const inline

inline size_t nslots() const

inline bool operator-=(SlotPtr slot)

Defined in src/base/include/icy/signal.h:383

Detaches the slot matching slot's delegate; equivalent to detach(slot).

Returns

true if removed.

Signal

Signal() = default

Defined in src/base/include/icy/signal.h:385

Defaulted constructor.

~Signal

inline

inline ~Signal()

Defined in src/base/include/icy/signal.h:387

Signal

inline

inline Signal(const Signal & r)

Defined in src/base/include/icy/signal.h:394

Copy constructor; copies the slot list and last-assigned ID from r.

Parameters

Parameter	Type	Description
`r`	const `Signal` &	The signal to copy from.

operator=

inline

inline Signal & operator=(const Signal & r)

Defined in src/base/include/icy/signal.h:403

Copy assignment operator; copies the slot list and last-assigned ID from r.

Returns

Reference to this signal.

Parameters

Parameter	Type	Description
`r`	const `Signal` &	The signal to copy from.

Public Types

Name	Description
`Function`
`SlotPtr`
`Slot`
`SlotNode`

Function

using Function = std::function< RT(Args...)>

Defined in src/base/include/icy/signal.h:145

SlotPtr

using SlotPtr = std::shared_ptr< internal::Slot< RT, Args... > >

Defined in src/base/include/icy/signal.h:146

Slot

using Slot = internal::Slot< RT, Args... >

Defined in src/base/include/icy/signal.h:147

SlotNode

using SlotNode = internal::SlotNode< RT, Args... >

Defined in src/base/include/icy/signal.h:148

Private Attributes

Return	Name	Description
`MutexT`	`_mutex`
`SlotNode` *	`_head`
`SlotNode` *	`_tail`
`size_t`	`_liveCount`
`int`	`_lastId`
`EmitDepth`	`_emitDepth`
`SweepFlag`	`_needsSweep`

_mutex

MutexT _mutex

Defined in src/base/include/icy/signal.h:625

_head

SlotNode * _head = nullptr

Type: SlotNode *

Defined in src/base/include/icy/signal.h:626

_tail

SlotNode * _tail = nullptr

Type: SlotNode *

Defined in src/base/include/icy/signal.h:627

_liveCount

size_t _liveCount = 0

Defined in src/base/include/icy/signal.h:628

_lastId

int _lastId = 0

Defined in src/base/include/icy/signal.h:629

_emitDepth

EmitDepth _emitDepth {}

Defined in src/base/include/icy/signal.h:630

_needsSweep

SweepFlag _needsSweep {}

Defined in src/base/include/icy/signal.h:631

Private Methods

Return	Name	Description
`size_t`	`killMatchingLocked` const inline
`void`	`insertSlotLocked` const inline
`void`	`appendSlotLocked` const inline
`void`	`eraseNodeLocked` const inline
`size_t`	`emitDepthLocked` const inline
`void`	`beginEmitLocked` const inline
`bool`	`endEmitLocked` const inline
`void`	`requestSweepLocked` const inline
`bool`	`consumeSweepRequest` const inline
`void`	`sweepLocked` const inline
`void`	`finishEmit` inline
`void`	`clearNodesLocked` const inline
`void`	`resetEmitState` inline
std::pair< std::vector< `SlotPtr` >, int >	`snapshotState` const inline
`void`	`restoreState` inline

killMatchingLocked

const inline

template<typename Matcher> inline size_t killMatchingLocked(Matcher && matcher, bool removeAll) const

Defined in src/base/include/icy/signal.h:418

insertSlotLocked

const inline

inline void insertSlotLocked(SlotPtr slot) const

Defined in src/base/include/icy/signal.h:444

appendSlotLocked

const inline

inline void appendSlotLocked(SlotPtr slot) const

Defined in src/base/include/icy/signal.h:471

eraseNodeLocked

const inline

inline void eraseNodeLocked(SlotNode * node) const

Defined in src/base/include/icy/signal.h:483

emitDepthLocked

const inline

inline size_t emitDepthLocked() const

Defined in src/base/include/icy/signal.h:498

beginEmitLocked

const inline

inline void beginEmitLocked() const

Defined in src/base/include/icy/signal.h:506

endEmitLocked

const inline

inline bool endEmitLocked() const

Defined in src/base/include/icy/signal.h:514

requestSweepLocked

const inline

inline void requestSweepLocked() const

Defined in src/base/include/icy/signal.h:522

consumeSweepRequest

const inline

inline bool consumeSweepRequest() const

Defined in src/base/include/icy/signal.h:530

sweepLocked

const inline

inline void sweepLocked() const

Defined in src/base/include/icy/signal.h:541

finishEmit

inline

inline void finishEmit()

Defined in src/base/include/icy/signal.h:551

clearNodesLocked

const inline

inline void clearNodesLocked() const

Defined in src/base/include/icy/signal.h:580

resetEmitState

inline

inline void resetEmitState()

Defined in src/base/include/icy/signal.h:593

snapshotState

const inline

inline std::pair< std::vector< SlotPtr >, int > snapshotState() const

Defined in src/base/include/icy/signal.h:604

restoreState

inline

inline void restoreState(std::vector< SlotPtr > snapshot, int lastId)

Defined in src/base/include/icy/signal.h:616

Private Static Attributes

Return	Name	Description
`constexpr bool`	`threadSafe` static constexpr

threadSafe

static constexpr

constexpr bool threadSafe = !std::is_same_v<MutexT, NullSharedMutex>

Defined in src/base/include/icy/signal.h:413