Session storage

Session data stored in a PFS file per session. More...

Functions
void	dls_storage_invalidate_all (void)
	Delete the storage files of all sessions.
void	dls_storage_delete_logging_storage (DataLoggingSession *session)
	Delete the storage file of a session.
int32_t	dls_storage_read (DataLoggingSession *logging_session, uint8_t *buffer, int32_t num_bytes, uint32_t *new_read_offset)
	Read data from a session without consuming it.
int32_t	dls_storage_consume (DataLoggingSession *logging_session, int32_t num_bytes)
	Consume data from a session without reading it.
bool	dls_storage_write_session (DataLoggingSession *session)
	Move the data from a buffered session's RAM buffer to flash.
bool	dls_storage_write_data (DataLoggingSession *session, const void *data, uint32_t num_bytes)
	Write data directly to a session's file.
void	dls_storage_rebuild (void)
	Recreate the sessions stored in flash, called at boot from dls_init().

Detailed Description

Session data stored in a PFS file per session.

All functions must be called from KernelBG, except during dls_storage_rebuild() at boot. On a write error the session's file is deleted.

Function Documentation

dls_storage_consume()

int32_t dls_storage_consume	(	DataLoggingSession *	logging_session,
		int32_t	num_bytes
	)

Consume data from a session without reading it.

Parameters

logging_session	Session to consume from.
num_bytes	Number of bytes to consume. 0 only resynchronizes the read offset with the data already consumed, as done when rebuilding sessions at boot.

Returns

Number of bytes consumed, or -1 on error.

dls_storage_delete_logging_storage()

void dls_storage_delete_logging_storage

(

DataLoggingSession *

session

)

Delete the storage file of a session.

The file must not be open.

Parameters

session

Session.

dls_storage_invalidate_all()

void dls_storage_invalidate_all

(

void

)

Delete the storage files of all sessions.

dls_storage_read()

int32_t dls_storage_read	(	DataLoggingSession *	logging_session,
		uint8_t *	buffer,
		int32_t	num_bytes,
		uint32_t *	new_read_offset
	)

Read data from a session without consuming it.

Only whole items are read, so fewer bytes than requested may be returned.

Parameters

	logging_session	Session to read from.
[out]	buffer	Destination, or NULL to only get the number of bytes available.
	num_bytes	Maximum number of bytes to read, ignored when buffer is NULL.
[out]	new_read_offset	File offset of the byte following the data read.

Returns

Number of bytes read (or available), or -1 on error.

dls_storage_rebuild()

void dls_storage_rebuild

(

void

)

Recreate the sessions stored in flash, called at boot from dls_init().

dls_storage_write_data()

bool dls_storage_write_data	(	DataLoggingSession *	session,
		const void *	data,
		uint32_t	num_bytes
	)

Write data directly to a session's file.

Used for unbuffered sessions; the session must be locked with dls_lock_session().

Parameters

session	Session.
data	Data to write.
num_bytes	Length of data in bytes.

Returns

true on success.

dls_storage_write_session()

bool dls_storage_write_session

(

DataLoggingSession *

session

)

Move the data from a buffered session's RAM buffer to flash.

Must be called with the list mutex held. Does nothing for inactive or unbuffered sessions.

Parameters

session

Session.

Returns

true on success.