dataman.cpp File Reference

DATAMANAGER driver. More...

#include <px4_config.h>
#include <px4_defines.h>
#include <px4_module.h>
#include <px4_posix.h>
#include <px4_tasks.h>
#include <px4_getopt.h>
#include <stdio.h>
#include <stdbool.h>
#include <stdlib.h>
#include <errno.h>
#include <fcntl.h>
#include <systemlib/err.h>
#include <queue.h>
#include <string.h>
#include <semaphore.h>
#include <unistd.h>
#include <drivers/drv_hrt.h>
#include "dataman.h"
#include <parameters/param.h>

Classes
struct	dm_operations_t
struct	work_q_item_t
	Work task work item. More...
struct	work_q_t

Macros
#define	DM_SECTOR_HDR_SIZE   4 /* data manager per item header overhead */

Typedefs
typedef struct dm_operations_t	dm_operations_t

Enumerations
enum	dm_function_t {   dm_write_func = 0, dm_read_func, dm_clear_func, dm_restart_func,   dm_number_of_funcs }
	Types of function calls supported by the worker task.
enum	{ BACKEND_NONE = 0, BACKEND_FILE, BACKEND_RAM, BACKEND_LAST }

Functions
__BEGIN_DECLS __EXPORT int	dataman_main (int argc, char *argv[])
__EXPORT ssize_t	dm_write (dm_item_t item, unsigned index, dm_persitence_t persistence, const void *buf, size_t count)
	Write to the data manager file. More...
__EXPORT ssize_t	dm_read (dm_item_t item, unsigned index, void *buf, size_t count)
	Retrieve from the data manager file. More...
__EXPORT int	dm_clear (dm_item_t item)
	Clear a data Item. More...
__EXPORT int	dm_lock (dm_item_t item)
	Lock all items of a type. More...
__EXPORT int	dm_trylock (dm_item_t item)
	Try to lock all items of a type (. More...
__EXPORT void	dm_unlock (dm_item_t item)
	Unlock a data Item. More...
__EXPORT int	dm_restart (dm_reset_reason reason)
	Tell the data manager about the type of the last reset.

Variables
const size_t	k_work_item_allocation_chunk_size = 8

Detailed Description

DATAMANAGER driver.

Author

Jean Cyr

Lorenz Meier

Julian Oes

Thomas Gubler

David Sidrane

Function Documentation

dm_clear()

__EXPORT int dm_clear

(

dm_item_t

item

)

Clear a data Item.

Erase all items of this type.

dm_lock()

__EXPORT int dm_lock

(

dm_item_t

item

)

Lock all items of a type.

Can be used for atomic updates of multiple items (single items are always updated atomically). Note that this lock is independent from dm_read & dm_write calls.

Returns

0 on success and lock taken, -1 on error (lock not taken, errno set)

dm_read()

__EXPORT ssize_t dm_read	(	dm_item_t	item,
		unsigned	index,
		void *	buf,
		size_t	count
	)

Retrieve from the data manager file.

Retrieve from the data manager store.

dm_trylock()

__EXPORT int dm_trylock

(

dm_item_t

item

)

Try to lock all items of a type (.

See also

sem_trywait()).

Returns

0 if lock is taken, -1 otherwise (on error or if already locked. errno is set accordingly)

dm_unlock()

__EXPORT void dm_unlock

(

dm_item_t

item

)

Unlock a data Item.

Unlock all items of a type.

dm_write()

__EXPORT ssize_t dm_write	(	dm_item_t	item,
		unsigned	index,
		dm_persitence_t	persistence,
		const void *	buf,
		size_t	count
	)

Write to the data manager file.

write to the data manager store