Detailed Description

Detects when USB devices are added or removed.

The HotplugAgent will run a callback when a USB device is added or removed. On systems with libusb >= 1.0.16 which also support hotplug we'll use the Hotplug API, otherwise we'll periodically check for devices.

Public Types
enum	EventType { DEVICE_ADDED, DEVICE_REMOVED }

typedef ola::Callback2< void, EventType, struct libusb_device * >	NotificationCallback
	Called when a USB device has been added or removed. More...

Public Member Functions
	HotplugAgent (NotificationCallback *notification_cb, int debug_level)
	Create a new HotplugAgent. More...

	~HotplugAgent ()
	Destructor. More...

AsynchronousLibUsbAdaptor *	GetUSBAdaptor () const
	Get the AsynchronousLibUsbAdaptor to use. More...

bool	Init ()
	Initialize the hotplug agent. More...

bool	Start ()
	Start the hotplug agent. More...

void	HaltNotifications ()
	Prevent any further notifications from occurring. More...

bool	Stop ()
	Stop the HotplugAgent. More...

Member Typedef Documentation

◆ NotificationCallback

typedef ola::Callback2<void, EventType, struct libusb_device*> ola::usb::HotplugAgent::NotificationCallback

Called when a USB device has been added or removed.

Template Parameters

EventType	The type of the event.
The	libusb device for this event.

The callback can be run in either the thread calling Start() or from an internal hotplug thread. However it won't be called from both at once.

Member Enumeration Documentation

◆ EventType

enum ola::usb::HotplugAgent::EventType

Enumerator
DEVICE_ADDED	The device was added.
DEVICE_REMOVED	The device ws removed.

Constructor & Destructor Documentation

◆ HotplugAgent()

ola::usb::HotplugAgent::HotplugAgent	(	NotificationCallback *	notification_cb,
		int	debug_level
	)

Create a new HotplugAgent.

Parameters

notification_cb	The callback to run when the device is added or removed. Ownership is transferred.
debug_level	The libusb debug level.

◆ ~HotplugAgent()

ola::usb::HotplugAgent::~HotplugAgent ( )

Destructor.

This will stop the HotplugAgent if it's still running.

Member Function Documentation

◆ GetUSBAdaptor()

AsynchronousLibUsbAdaptor * ola::usb::HotplugAgent::GetUSBAdaptor ( ) const

Get the AsynchronousLibUsbAdaptor to use.

Returns: An AsynchronousLibUsbAdaptor, ownership is not transferred.

Precondition: Must be called after Init()

The adaptor is valid until the call to Stop().

◆ HaltNotifications()

void ola::usb::HotplugAgent::HaltNotifications ( )

Prevent any further notifications from occurring.

Once this returns, the NotificationCallback will not be called.

◆ Init()

bool ola::usb::HotplugAgent::Init ( )

Initialize the hotplug agent.

Returns: true if the agent started correctly, false otherwise.

◆ Start()

bool ola::usb::HotplugAgent::Start ( )

Start the hotplug agent.

Returns: true if the agent started correctly, false otherwise.

Precondition: Init() has been called and returned true.

◆ Stop()

bool ola::usb::HotplugAgent::Stop ( )

Stop the HotplugAgent.

Returns: true if stopped correctly, false otherwise.

Stop() may result in notifications being run, however once Stop() returns, no further calls to the notification callback will be made.

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

libs/usb/HotplugAgent.h
libs/usb/HotplugAgent.cpp