Sync

Write-back of dirty records to the phone. More...

Data Structures
struct	BlobDBSyncSession
	Sync session, writing the dirty records of a database back to the phone one at a time. More...

Enumerations
enum	BlobDBSyncSessionState { BlobDBSyncSessionStateIdle = 0 , BlobDBSyncSessionStateWaitingForAck = 1 }
	State of a sync session. More...
enum	BlobDBSyncSessionType { BlobDBSyncSessionTypeDB , BlobDBSyncSessionTypeRecord }
	Scope of a sync session. More...

Functions
status_t	blob_db_sync_db (BlobDBId db_id)
	Start writing back the dirty records of a database.
status_t	blob_db_sync_record (BlobDBId db_id, const void *key, int key_len, time_t last_updated)
	Start writing a single record to the phone.
BlobDBSyncSession *	blob_db_sync_get_session_for_id (BlobDBId db_id)
	Get the whole-database sync session of a database.
BlobDBSyncSession *	blob_db_sync_get_session_for_token (BlobDBToken token)
	Get the sync session waiting for a response with a given token.
void	blob_db_sync_next (BlobDBSyncSession *session)
	Mark the current record as synced and send the next one.
void	blob_db_sync_cancel (BlobDBSyncSession *session)
	Cancel a sync and free the session.

Detailed Description

Write-back of dirty records to the phone.

Records are sent one at a time over the BlobDB sync endpoint; each acknowledgement marks the record as synced and sends the next one. A write without answer is retried every 30 seconds and the session is abandoned after 5 minutes.

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Data Structure Documentation

BlobDBSyncSession

struct BlobDBSyncSession

Sync session, writing the dirty records of a database back to the phone one at a time.

Data Fields
RegularTimerInfo	abandon_timer	Cancels the session after repeated timeouts.
BlobDBToken	current_token	Token of the write in flight.
BlobDBId	db_id	Database being synced.
BlobDBDirtyItem *	dirty_list	Records left to sync; the head is the one in flight.
ListNode	node	List node.
uint32_t	session_id	Unique id, never reused. Deferred timer callbacks carry this instead of a session pointer so they can detect a session that has already been freed.
BlobDBSyncSessionType	session_type	Session scope.
BlobDBSyncSessionState	state	Session state.
RegularTimerInfo	timeout_timer	Retries the current write when the phone does not answer in time.

Enumeration Type Documentation

BlobDBSyncSessionState

enum BlobDBSyncSessionState

State of a sync session.

Enumerator
BlobDBSyncSessionStateIdle	No write in flight.
BlobDBSyncSessionStateWaitingForAck	Waiting for the phone to acknowledge the current write.

BlobDBSyncSessionType

enum BlobDBSyncSessionType

Scope of a sync session.

Enumerator
BlobDBSyncSessionTypeDB	Whole database, written back with WRITEBACK and ended with SYNC_DONE.
BlobDBSyncSessionTypeRecord	Single record, written with WRITE.

Function Documentation

blob_db_sync_cancel()

void blob_db_sync_cancel

(

BlobDBSyncSession *

session

)

Cancel a sync and free the session.

Pending records are synced next time.

Parameters

session

Session to cancel.

blob_db_sync_db()

status_t blob_db_sync_db

(

BlobDBId

db_id

)

Start writing back the dirty records of a database.

Sends SYNC_DONE immediately when there is nothing to sync.

Parameters

db_id

Database to sync.

Return values

S_SUCCESS	Sync started.
S_NO_ACTION_REQUIRED	No dirty records.
E_BUSY	A sync of this database is already in progress.
E_INVALID_ARGUMENT	Invalid database.

blob_db_sync_get_session_for_id()

BlobDBSyncSession * blob_db_sync_get_session_for_id

(

BlobDBId

db_id

)

Get the whole-database sync session of a database.

Single-record sessions are not returned.

Parameters

db_id

Database.

Returns

Session, NULL if no sync is in progress.

blob_db_sync_get_session_for_token()

BlobDBSyncSession * blob_db_sync_get_session_for_token

(

BlobDBToken

token

)

Get the sync session waiting for a response with a given token.

Parameters

token

Token of the write.

Returns

Session, NULL if none matches.

blob_db_sync_next()

void blob_db_sync_next

(

BlobDBSyncSession *

session

)

Mark the current record as synced and send the next one.

When the list is exhausted, picks up records that became dirty meanwhile, or ends the session and frees it.

Parameters

session

Session; may be freed by the call.

blob_db_sync_record()

status_t blob_db_sync_record	(	BlobDBId	db_id,
		const void *	key,
		int	key_len,
		time_t	last_updated
	)

Start writing a single record to the phone.

If a whole-database sync is in progress, the record is picked up by it instead.

Parameters

db_id	Database of the record.
key	Key data.
key_len	Length of key in bytes.
last_updated	Modification time of the record.

Return values

S_SUCCESS	Sync started or deferred to the running session.
E_INVALID_ARGUMENT	Invalid database.