CDevNode Class Reference

Inheritance diagram for CDevNode:

Public Member Functions
virtual int	open (cdev::file_t *handlep)
	Handle an open of the device. More...
virtual int	close (cdev::file_t *handlep)
	Handle a close of the device. More...
virtual ssize_t	write (cdev::file_t *handlep, const char *buffer, size_t buflen)
	Perform a write to the device. More...
virtual ssize_t	read (cdev::file_t *handlep, char *buffer, size_t buflen)
	Perform a read from the device. More...
Public Member Functions inherited from cdev::CDev
	CDev (const char *devname)
	Constructor. More...
virtual int	init ()
virtual off_t	seek (file_t *filep, off_t offset, int whence)
	Perform a logical seek operation on the device. More...
virtual int	ioctl (file_t *filep, int cmd, unsigned long arg)
	Perform an ioctl operation on the device. More...
virtual int	poll (file_t *filep, px4_pollfd_struct_t *fds, bool setup)
	Perform a poll setup/teardown operation. More...
const char *	get_devname () const
	Get the device name. More...

Additional Inherited Members
Protected Member Functions inherited from cdev::CDev
virtual pollevent_t	poll_state (file_t *filep)
	Check the current state of the device for poll events from the perspective of the file. More...
virtual void	poll_notify (pollevent_t events)
	Report new poll events. More...
virtual void	poll_notify_one (px4_pollfd_struct_t *fds, pollevent_t events)
	Internal implementation of poll_notify. More...
virtual int	open_first (file_t *filep)
	Notification of the first open. More...
virtual int	close_last (file_t *filep)
	Notification of the last close. More...
virtual int	register_class_devname (const char *class_devname)
	Register a class device name, automatically adding device class instance suffix if need be. More...
virtual int	unregister_class_devname (const char *class_devname, unsigned class_instance)
	Register a class device name, automatically adding device class instance suffix if need be. More...
void	lock ()
	Take the driver lock. More...
void	unlock ()
	Release the driver lock.
Protected Attributes inherited from cdev::CDev
px4_sem_t	_lock
	lock to protect access to all class members (also for derived classes)
Static Protected Attributes inherited from cdev::CDev
static const px4_file_operations_t	fops = {}
	Pointer to the default cdev file operations table; useful for registering clone devices etc.

Member Function Documentation

close()

int CDevNode::close ( cdev::file_t *  filep )

virtual

Handle a close of the device.

This function is called for every close of the device. The default implementation maintains _open_count and returns OK as long as it is not zero.

Parameters

filep

Pointer to the NuttX file structure.

Returns

OK if the close was successful, -errno otherwise.

Reimplemented from cdev::CDev.

open()

int CDevNode::open ( cdev::file_t *  filep )

virtual

Handle an open of the device.

This function is called for every open of the device. The default implementation maintains _open_count and always returns OK.

Parameters

filep

Pointer to the NuttX file structure.

Returns

OK if the open is allowed, -errno otherwise.

Reimplemented from cdev::CDev.

read()

ssize_t CDevNode::read ( cdev::file_t *  filep, char *  buffer, size_t  buflen  )

virtual

Perform a read from the device.

The default implementation returns -ENOSYS.

Parameters

filep	Pointer to the NuttX file structure.
buffer	Pointer to the buffer into which data should be placed.
buflen	The number of bytes to be read.

Returns

The number of bytes read or -errno otherwise.

Reimplemented from cdev::CDev.

write()

ssize_t CDevNode::write ( cdev::file_t *  filep, const char *  buffer, size_t  buflen  )

virtual

Perform a write to the device.

The default implementation returns -ENOSYS.

Parameters

filep	Pointer to the NuttX file structure.
buffer	Pointer to the buffer from which data should be read.
buflen	The number of bytes to be written.

Returns

The number of bytes written or -errno otherwise.

Reimplemented from cdev::CDev.

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

• src/lib/cdev/test/cdevtest_example.cpp