Device Struct Reference

Device tab structure. More...

#include <Devtab.hxx>

Inheritance diagram for Device:

Classes
struct	SelectInfo
	Select wakeup information. More...

Public Member Functions
	Device (const char *name)
	Constructor.
virtual	~Device ()
	Destructor.

Static Public Member Functions
static int	open (struct _reent *reent, const char *path, int flags, int mode)
	Open a file or device.
static int	close (struct _reent *reent, int fd)
	Close a file or device.
static int	stat (struct _reent *reent, const char *path, struct stat *stat)
	Get the status information of a file or device.
static int	select (int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, long long timeout)
	POSIX select().
static void	select_clear ()
	Clears the current thread's select bits.
Static Public Member Functions inherited from FileIO
static ssize_t	read (struct _reent *reent, int fd, void *buf, size_t count)
	Read from a file or device.
static ssize_t	write (struct _reent *reent, int fd, const void *buf, size_t count)
	Write to a file or device.
static _off_t	lseek (struct _reent *reent, int fd, _off_t offset, int whence)
	Change the offset index of a file or device.
static int	fstat (struct _reent *reent, int fd, struct stat *stat)
	Get the status information of a file or device.
static int	ioctl (int fd, unsigned long int key, unsigned long data)
	Request and ioctl transaction.
static int	fcntl (int fd, int cmd, unsigned long data)
	Manipulate a file descriptor.
static bool	is_device (int fd)
	Test if the file descriptor belongs to a device.

Protected Member Functions
virtual mode_t	get_mode ()
	Get the mode of the device.
Protected Member Functions inherited from FileIO
	FileIO (const char *name)
	Constructor.
virtual	~FileIO ()
	Destructor.
virtual int	open (File *file, const char *path, int flags, int mode)=0
	Open a file or device.
virtual int	close (File *file)=0
	Close a file or device.
virtual ssize_t	read (File *file, void *buf, size_t count)=0
	Read from a file or device.
virtual ssize_t	write (File *file, const void *buf, size_t count)=0
	Write to a file or device.
virtual off_t	lseek (File *f, off_t offset, int whence)
	Seek method.
virtual int	fstat (File *file, struct stat *stat)=0
	Get the status information of a file or device.
virtual int	ioctl (File *file, unsigned long int key, unsigned long data)
	Request an ioctl transaction.
virtual int	fcntl (File *file, int cmd, unsigned long data)
	Manipulate a file descriptor.
virtual bool	select (File *file, int mode)
	Device select method.

Static Protected Member Functions
static void	select_insert (SelectInfo *info)
	Add client to list of clients needing woken.
static void	select_wakeup (SelectInfo *info)
	Wakeup the list of clients needing woken.
static void	select_wakeup_from_isr (SelectInfo *info, int *woken)
	Wakeup the list of clients needing woken.
Static Protected Member Functions inherited from FileIO
static int	fd_alloc (void)
	Allocate a free file descriptor.
static void	fd_free (int fd)
	Free up a file descriptor.
static File *	file_lookup (int fd)
	Looks up a reference to a File corresponding to a given file descriptor.
static int	fd_lookup (File *file)
	Looks up a file descriptor corresponding to a given File reference.

Private Member Functions
	DISALLOW_COPY_AND_ASSIGN (Device)

Private Attributes
Device *	next
	next device in linked list
Device *	prev
	previous device in linked list

Static Private Attributes
static Device *	first = NULL
	first device in linked list

Friends
class	DeviceBufferBase
	allow class DeviceBuffer access to select() related members.
class	OSSelectWakeup
	allow class OSSelectWakeup access to select() related members.

Additional Inherited Members
Protected Attributes inherited from FileIO
const char *	name
	device name
Static Protected Attributes inherited from FileIO
static const unsigned int	numOpenFiles = 20
static File	files []
	File descriptor pool.
static OSMutex	mutex
	mutual exclusion for fileio

Detailed Description

Device tab structure.

Definition at line 431 of file Devtab.hxx.

Constructor & Destructor Documentation

Device()

Device::Device

(

const char *

name

)

Constructor.

Parameters

name	name of device in file system. Pointer must be valid throughout the entire lifetime.

Definition at line 52 of file Device.cxx.

~Device()

Device::~Device ( )

virtual

Destructor.

Definition at line 68 of file Device.cxx.

Member Function Documentation

close()

int Device::close ( struct _reent *  reent, int  fd  )

static

Close a file or device.

Parameters

reent	thread save reentrant structure
fd	file descriptor to close

Returns

0 upon success, -1 upon failure with errno containing the cause

Definition at line 134 of file Device.cxx.

get_mode()

virtual mode_t Device::get_mode ( )

inlineprotectedvirtual

Get the mode of the device.

Returns

mode of device.

Reimplemented in Node.

Definition at line 506 of file Devtab.hxx.

open()

int Device::open ( struct _reent *  reent, const char *  path, int  flags, int  mode  )

static

Open a file or device.

Parameters

reent	thread save reentrant structure
path	file or device name
flags	open flags
mode	open mode, ignored in this implementation

Returns

0 upon success, -1 upon failure with errno containing the cause

Definition at line 93 of file Device.cxx.

select()

int Device::select ( int  nfds, fd_set *  readfds, fd_set *  writefds, fd_set *  exceptfds, long long  timeout  )

static

POSIX select().

Parameters

nfds	highest numbered file descriptor in any of the three, sets plus 1
readfds	fd_set of file descritpors to pend on read active
writefds	fd_set of file descritpors to pend on write active
exceptfds	fd_set of file descritpors to pend on error active
timeout	timeout in nsec to wait, if 0, return immediately, if < 0 wait forever

Returns

on success, number of file descriptors in the three sets that are active, 0 on timeout, -1 with errno set appropriately upon error.

Definition at line 96 of file Select.cxx.

select_clear()

void Device::select_clear ( )

static

Clears the current thread's select bits.

This is used by select and ::pselect to ensure the necessary atomicity.

Definition at line 78 of file Select.cxx.

select_insert()

void Device::select_insert ( SelectInfo *  info )

staticprotected

Add client to list of clients needing woken.

Add client to list of clients needing woken,.

Parameters

info	wakeup event instance

Todo:

do we need the critical lock here, or are we always already locked?

Definition at line 197 of file Select.cxx.

select_wakeup()

void Device::select_wakeup ( SelectInfo *  info )

staticprotected

Wakeup the list of clients needing woken.

Wakeup the list of clients needing woken,.

Parameters

info	wakeup event instance

Definition at line 210 of file Select.cxx.

select_wakeup_from_isr()

void Device::select_wakeup_from_isr ( SelectInfo *  info, int *  woken  )

staticprotected

Wakeup the list of clients needing woken.

Wakeup the list of clients needing woken,.

from ISR context.

Parameters

info	wakeup event instance
woken	is the task woken up
info	wakeup event instance

Definition at line 224 of file Select.cxx.

stat()

int Device::stat ( struct _reent *  reent, const char *  path, struct stat *  stat  )

static

Get the status information of a file or device.

Parameters

reent	thread save reentrant structure
path	file or device name
stat	structure to fill status info into

Returns

0 upon success, -1 upon failure with errno containing the cause

Definition at line 165 of file Device.cxx.

Friends And Related Symbol Documentation

DeviceBufferBase

friend class DeviceBufferBase

friend

allow class DeviceBuffer access to select() related members.

Definition at line 528 of file Devtab.hxx.

OSSelectWakeup

friend class OSSelectWakeup

friend

allow class OSSelectWakeup access to select() related members.

Definition at line 531 of file Devtab.hxx.

Member Data Documentation

first

Device * Device::first = NULL

staticprivate

first device in linked list

Definition at line 535 of file Devtab.hxx.

next

Device* Device::next

private

next device in linked list

Definition at line 538 of file Devtab.hxx.

prev

Device* Device::prev

private

previous device in linked list

Definition at line 541 of file Devtab.hxx.

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

• Devtab.hxx
• Device.cxx
• Select.cxx