RamDisk Class Reference

A simple device driver that reads/write data from a block of memory in a typed array either statically or dynamically allocated. More...

#include <RamDisk.hxx>

Inheritance diagram for RamDisk:

Public Member Functions
	RamDisk (const char *path, size_t size)
	Allocates space on the heap for the ramdisk of size ‘size’.
template<class T >
	RamDisk (const char *path, T *data, bool read_only=false)
	Uses an existing variable for backing the ramdisk structure.
Public Member Functions inherited from RamDiskBase
	RamDiskBase (const char *path, void *data, unsigned size, bool read_only)
	Constructor.
Public Member Functions inherited from Device
	Device (const char *name)
	Constructor.
virtual	~Device ()
	Destructor.

Additional Inherited Members
Static Public Member Functions inherited from Device
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 inherited from RamDiskBase
off_t	file_size ()
Protected Member Functions inherited from Node
	Node (const char *name)
	Constructor.
virtual	~Node ()
	Destructor.
int	close (File *) OVERRIDE
	Close method.
virtual int	fstat (File *file, struct stat *stat) override
	Get the status information of a file or device.
Protected Member Functions inherited from FileIO
	FileIO (const char *name)
	Constructor.
virtual	~FileIO ()
	Destructor.
virtual off_t	lseek (File *f, off_t offset, int whence)
	Seek method.
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 inherited from Device
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.
Protected Attributes inherited from RamDiskBase
uint8_t *	data_
	Pointer to data content.
unsigned	actualSize_ = 0
	What's the larget file offset that we received an actual write for.
unsigned	size_: 30
	How many bytes we are exporting.
unsigned	readOnly_: 1
	1 ifreadonly file.
unsigned	owned_: 1
	1 if we own the data bytes and need to free()them upon exit.
Protected Attributes inherited from Node
OSMutex	lock_
	protects internal structures.
mode_t	mode_
	File open mode, such as O_NONBLOCK.
unsigned int	references_
	number of open references
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

A simple device driver that reads/write data from a block of memory in a typed array either statically or dynamically allocated.

Example: RamDisk rdisk("/dev/volatile_config", 256);

Definition at line 152 of file RamDisk.hxx.

Constructor & Destructor Documentation

RamDisk() [1/2]

RamDisk::RamDisk ( const char *  path, size_t  size  )

inline

Allocates space on the heap for the ramdisk of size ‘size’.

Definition at line 156 of file RamDisk.hxx.

RamDisk() [2/2]

template<class T >

RamDisk::RamDisk ( const char *  path, T *  data, bool  read_only = false  )

inline

Uses an existing variable for backing the ramdisk structure.

The variable is usually of a struct type, such as openlcb::SimpleNodeDynamicValues. The variable may also be in flash.

Parameters

path	is the device node name (e.g "/etc/node_config")
data	is the variable to export
read_only	if set, writes will be ignored.

Definition at line 170 of file RamDisk.hxx.

~RamDisk()

RamDisk::~RamDisk ( )

inline

Definition at line 176 of file RamDisk.hxx.

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

• RamDisk.hxx