c7222::SafeLed Class Reference

LED wrapper that prevents simultaneous control from multiple threads. More...

#include <safe_led.hpp>

Inheritance diagram for c7222::SafeLed:

Collaboration diagram for c7222::SafeLed:

Public Member Functions
	SafeLed (Led &led)
	Construct a SafeLed wrapper around an existing Led instance.
	SafeLed (PicoWBoard::LedId id)
	Construct a SafeLed wrapper for a board LED by logical ID.
void	Acquire ()
	Acquire exclusive control of the LED (blocks until available).
bool	AcquireFor (uint32_t timeout)
	Acquire exclusive control with a timeout.
void	Release ()
	Release exclusive control of the LED.
bool	IsHeld () const
	Return true if this object currently holds the lock.
void	Set (bool on)
	Set the LED state (requires Acquire()).
void	On ()
	Turn the LED on (requires Acquire()).
void	Off ()
	Turn the LED off (requires Acquire()).
void	Toggle ()
	Toggle the LED (requires Acquire()).
Public Member Functions inherited from c7222::NonCopyable
	NonCopyable (const NonCopyable &)=delete
NonCopyable &	operator= (const NonCopyable &)=delete
	NonCopyable (NonCopyable &&)=default
NonCopyable &	operator= (NonCopyable &&)=default
Public Member Functions inherited from c7222::NonMovable
	NonMovable (const NonMovable &)=default
NonMovable &	operator= (const NonMovable &)=default
	NonMovable (NonMovable &&)=delete
NonMovable &	operator= (NonMovable &&)=delete

Additional Inherited Members
Protected Member Functions inherited from c7222::NonCopyableNonMovable
	NonCopyableNonMovable ()=default
	~NonCopyableNonMovable ()=default
Protected Member Functions inherited from c7222::NonCopyable
	NonCopyable ()=default
	~NonCopyable ()=default
Protected Member Functions inherited from c7222::NonMovable
	NonMovable ()=default
	~NonMovable ()=default

Detailed Description

LED wrapper that prevents simultaneous control from multiple threads.

Usage pattern:

1. Call Acquire() to obtain exclusive control.
2. Perform one or more LED operations.
3. Call Release() when done.

All LED operations assert that the caller has acquired the lock.

Synchronization model and purpose:

• Uses a std::mutex to guard ownership state (locked_) across multiple tasks that may try to control the LED.
• Uses a std::condition_variable to block waiters in Acquire()/AcquireFor() until the LED becomes available, avoiding busy-waiting.

RAII considerations:

• RAII is intentionally not used to represent LED ownership because ownership spans multiple calls and can be transferred between tasks over time. A scoped guard would tie ownership to a single scope and thread, which does not match the intended usage pattern (press/release workflows).
• RAII is used internally for mutex management: Acquire()/AcquireFor() use std::unique_lock because std::condition_variable requires it for atomic unlock-and-wait semantics. The lock is released on all exit paths.

Constructor & Destructor Documentation

SafeLed() [1/2]

c7222::SafeLed::SafeLed ( Led &  led )

explicit

Construct a SafeLed wrapper around an existing Led instance.

SafeLed() [2/2]

c7222::SafeLed::SafeLed ( PicoWBoard::LedId  id )

inlineexplicit

Construct a SafeLed wrapper for a board LED by logical ID.

This is a convenience constructor that looks up the LED from the Platform singleton. It assumes the Platform and PicoWBoard have been initialized and that the specified LED exists.

Member Function Documentation

Acquire()

void c7222::SafeLed::Acquire

(

)

Acquire exclusive control of the LED (blocks until available).

AcquireFor()

bool c7222::SafeLed::AcquireFor

(

uint32_t

timeout

)

Acquire exclusive control with a timeout.

Parameters

timeout

Maximum time to wait.

Returns

true if the lock was acquired, false on timeout.

Here is the caller graph for this function:

IsHeld()

bool c7222::SafeLed::IsHeld

(

)

const

Return true if this object currently holds the lock.

Off()

void c7222::SafeLed::Off

(

)

Turn the LED off (requires Acquire()).

Here is the call graph for this function:

Here is the caller graph for this function:

On()

void c7222::SafeLed::On

(

)

Turn the LED on (requires Acquire()).

Here is the call graph for this function:

Here is the caller graph for this function:

Release()

void c7222::SafeLed::Release

(

)

Release exclusive control of the LED.

Here is the caller graph for this function:

Set()

void c7222::SafeLed::Set

(

bool

on

)

Set the LED state (requires Acquire()).

Here is the call graph for this function:

Toggle()

void c7222::SafeLed::Toggle

(

)

Toggle the LED (requires Acquire()).

Here is the call graph for this function:

---

The documentation for this class was generated from the following files:

• libs/elec_c7222/examples/freertos-device-cpp/safe_led.hpp
• libs/elec_c7222/examples/freertos-device-cpp/safe_led.cpp