18.2.9.2. RTPSReader¶

class RTPSReader : public eprosima::fastrtps::rtps::Endpoint, public eprosima::fastdds::statistics::StatisticsReaderImpl¶

Class RTPSReader, manages the reception of data from its matched writers.

Subclassed by eprosima::fastrtps::rtps::StatefulReader, eprosima::fastrtps::rtps::StatelessReader

Public Functions

virtual bool matched_writer_add(const WriterProxyData &wdata) = 0¶

Add a matched writer represented by its attributes.

Parameters: wdata – Attributes of the writer to add.
Returns: True if correctly added.

virtual bool matched_writer_remove(const GUID_t &writer_guid, bool removed_by_lease = false) = 0¶

Remove a writer represented by its attributes from the matched writers.

Parameters

writer_guid – GUID of the writer to remove.
removed_by_lease – Whether the writer is being unmatched due to a participant drop.

Returns

True if correctly removed.

virtual bool matched_writer_is_matched(const GUID_t &writer_guid) = 0¶

Tells us if a specific Writer is matched against this reader.

Parameters: writer_guid – GUID of the writer to check.
Returns: True if it is matched.

virtual bool processDataMsg(CacheChange_t *change) = 0¶

Processes a new DATA message. Previously the message must have been accepted by function acceptMsgDirectedTo.

Parameters: change – Pointer to the CacheChange_t.
Returns: true if the reader accepts messages from the.

virtual bool processDataFragMsg(CacheChange_t *change, uint32_t sampleSize, uint32_t fragmentStartingNum, uint16_t fragmentsInSubmessage) = 0¶

Processes a new DATA FRAG message.

Parameters

change – Pointer to the CacheChange_t.
sampleSize – Size of the complete, assembled message.
fragmentStartingNum – Starting number of this particular message.
fragmentsInSubmessage – Number of fragments on this particular message.

Returns

true if the reader accepts message.

virtual bool processHeartbeatMsg(const GUID_t &writerGUID, uint32_t hbCount, const SequenceNumber_t &firstSN, const SequenceNumber_t &lastSN, bool finalFlag, bool livelinessFlag, fastdds::rtps::VendorId_t origin_vendor_id = c_VendorId_Unknown) = 0¶

Processes a new HEARTBEAT message.

Parameters

writerGUID –
hbCount –
firstSN –
lastSN –
finalFlag –
livelinessFlag –
origin_vendor_id –

Returns

true if the reader accepts messages from the.

virtual bool processGapMsg(const GUID_t &writerGUID, const SequenceNumber_t &gapStart, const SequenceNumberSet_t &gapList, fastdds::rtps::VendorId_t origin_vendor_id = c_VendorId_Unknown) = 0¶

Processes a new GAP message.

Parameters

writerGUID –
gapStart –
gapList –
origin_vendor_id –

Returns

true if the reader accepts messages from the.

virtual bool change_removed_by_history(CacheChange_t *change, WriterProxy *prox = nullptr) = 0¶

Method to indicate the reader that some change has been removed due to HistoryQos requirements.

Parameters

change – Pointer to the CacheChange_t.
prox – Pointer to the WriterProxy.

Returns

True if correctly removed.

ReaderListener *getListener() const¶

Get the associated listener, secondary attached Listener in case it is of compound type

Returns: Pointer to the associated reader listener.

bool setListener(ReaderListener *target)¶

Switch the ReaderListener kind for the Reader. If the RTPSReader does not belong to the built-in protocols it switches out the old one. If it belongs to the built-in protocols, it sets the new ReaderListener callbacks to be called after the built-in ReaderListener ones.

Parameters: target – Pointed to ReaderLister to attach
Returns: True is correctly set.

bool reserveCache(CacheChange_t **change, uint32_t dataCdrSerializedSize)¶

Reserve a CacheChange_t.

Parameters

change – Pointer to pointer to the Cache.
dataCdrSerializedSize – Size of the Cache.

Returns

True if correctly reserved.

void releaseCache(CacheChange_t *change)¶: Release a cacheChange.

virtual bool nextUnreadCache(CacheChange_t **change, WriterProxy **wp) = 0¶

Read the next unread CacheChange_t from the history

Parameters

change – Pointer to pointer of CacheChange_t
wp – Pointer to pointer to the WriterProxy

Returns

True if read.

virtual bool nextUntakenCache(CacheChange_t **change, WriterProxy **wp) = 0¶

Get the next CacheChange_t from the history to take.

Parameters

change – Pointer to pointer of CacheChange_t.
wp – Pointer to pointer to the WriterProxy.

Returns

True if read.

inline bool expectsInlineQos()¶

Returns: True if the reader expects Inline QOS.

inline ReaderHistory *getHistory()¶: Returns a pointer to the associated History.

inline eprosima::fastdds::rtps::IReaderDataFilter *get_content_filter() const¶

Returns: The content filter associated to this reader.

inline void set_content_filter(eprosima::fastdds::rtps::IReaderDataFilter *filter)¶

Set the content filter associated to this reader.

Parameters: filter – Pointer to the content filter to associate to this reader.

virtual bool isInCleanState() = 0¶

Returns there is a clean state with all Writers.

It occurs when the Reader received all samples sent by Writers. In other words, its WriterProxies are up to date.

Returns: There is a clean state with all Writers.

virtual void assert_writer_liveliness(const GUID_t &writer) = 0¶

Assert the liveliness of a matched writer.

Parameters: writer – GUID of the writer to assert.

virtual bool begin_sample_access_nts(CacheChange_t *change, WriterProxy *&wp, bool &is_future_change) = 0¶

Called just before a change is going to be deserialized.

Parameters

change – [in] Pointer to the change being accessed.
wp – [out] Writer proxy the change belongs to.
is_future_change – [out] Whether the change is in the future (i.e. there are earlier unreceived changes from the same writer).

Returns

Whether the change is still valid or not.

virtual void end_sample_access_nts(CacheChange_t *change, WriterProxy *&wp, bool mark_as_read) = 0¶

Called after the change has been deserialized.

Parameters

change – [in] Pointer to the change being accessed.
wp – [in] Writer proxy the change belongs to.
mark_as_read – [in] Whether the change should be marked as read or not.

virtual void change_read_by_user(CacheChange_t *change, WriterProxy *writer, bool mark_as_read = true) = 0¶

Called when the user has retrieved a change from the history.

Parameters

change – Pointer to the change to ACK
writer – Writer proxy of the change.
mark_as_read – Whether the change should be marked as read or not

bool is_sample_valid(const void *data, const GUID_t &writer, const SequenceNumber_t &sn) const¶

Checks whether the sample is still valid or is corrupted.

Parameters

data – Pointer to the sample data to check. If it does not belong to the payload pool passed to the reader on construction, it yields undefined behavior.
writer – GUID of the writer that sent data.
sn – Sequence number related to data.

Returns

true if the sample is valid

Public Members

LivelinessChangedStatus liveliness_changed_status_¶: The liveliness changed status struct as defined in the DDS.