Class astutedds::rtps::WriterHistoryCache

ClassList > astutedds > rtps > WriterHistoryCache

History cache for a DataWriter. More...

• #include <writer_history_cache.hpp>

Public Types

Type	Name
enum	HistoryKind

Public Functions

Type	Name
	WriterHistoryCache (const GUID_t & writer_guid, HistoryKind history_kind=HistoryKind::KEEP_LAST, size_t history_depth=10) Constructor.
SequenceNumber_t	add_sample (const std::vector< uint8_t > & data, const std::vector< uint8_t > & instance_key={}) Add a new sample to the cache.
void	clear () Clear all samples from the cache.
bool	empty () const Check if the cache has any samples.
SequenceNumber_t	get_first_seq_num () const Get the first available sequence number.
SequenceNumber_t	get_last_seq_num () const Get the last (highest) sequence number.
std::optional< CacheChange >	get_sample (const SequenceNumber_t & seq_num) const Get a sample by sequence number.
std::vector< CacheChange >	get_samples_in_range (const SequenceNumber_t & first, const SequenceNumber_t & last) const Get all samples in a sequence number range.
std::vector< CacheChange >	get_unacknowledged () const Get unacknowledged samples.
void	mark_acknowledged (const SequenceNumber_t & seq_num) Mark a sample as acknowledged.
void	mark_acknowledged_up_to (const SequenceNumber_t & up_to_seq_num) Mark all samples up to a sequence number as acknowledged.
void	remove_older_than (std::chrono::milliseconds max_age) Remove samples older than a certain age.
size_t	size () const Get number of samples in cache.

Detailed Description

Stores samples for reliable delivery and retransmission. Implements KEEP_LAST and KEEP_ALL history policies.

Public Types Documentation

enum HistoryKind

enum astutedds::rtps::WriterHistoryCache::HistoryKind {
    KEEP_LAST,
    KEEP_ALL
};

---

Public Functions Documentation

function WriterHistoryCache

Constructor.

explicit astutedds::rtps::WriterHistoryCache::WriterHistoryCache (
    const GUID_t & writer_guid,
    HistoryKind history_kind=HistoryKind::KEEP_LAST,
    size_t history_depth=10
) 

Parameters:

• writer_guid GUID of the owning writer
• history_kind KEEP_LAST or KEEP_ALL policy
• history_depth Maximum samples to keep (for KEEP_LAST)

---

function add_sample

Add a new sample to the cache.

SequenceNumber_t astutedds::rtps::WriterHistoryCache::add_sample (
    const std::vector< uint8_t > & data,
    const std::vector< uint8_t > & instance_key={}
) 

Parameters:

• data Serialized sample data
• instance_key Instance key (for keyed topics)

Returns:

Sequence number assigned to this sample

---

function clear

Clear all samples from the cache.

void astutedds::rtps::WriterHistoryCache::clear () 

---

function empty

Check if the cache has any samples.

bool astutedds::rtps::WriterHistoryCache::empty () const

Returns:

True if cache is empty

---

function get_first_seq_num

Get the first available sequence number.

SequenceNumber_t astutedds::rtps::WriterHistoryCache::get_first_seq_num () const

Returns:

First sequence number in the cache

---

function get_last_seq_num

Get the last (highest) sequence number.

SequenceNumber_t astutedds::rtps::WriterHistoryCache::get_last_seq_num () const

Returns:

Last sequence number in the cache

---

function get_sample

Get a sample by sequence number.

std::optional< CacheChange > astutedds::rtps::WriterHistoryCache::get_sample (
    const SequenceNumber_t & seq_num
) const

Parameters:

• seq_num Sequence number to retrieve

Returns:

The sample if found, nullopt otherwise

---

function get_samples_in_range

Get all samples in a sequence number range.

std::vector< CacheChange > astutedds::rtps::WriterHistoryCache::get_samples_in_range (
    const SequenceNumber_t & first,
    const SequenceNumber_t & last
) const

Parameters:

• first First sequence number (inclusive)
• last Last sequence number (inclusive)

Returns:

Vector of samples in the range

---

function get_unacknowledged

Get unacknowledged samples.

std::vector< CacheChange > astutedds::rtps::WriterHistoryCache::get_unacknowledged () const

Returns:

Vector of unacknowledged samples

---

function mark_acknowledged

Mark a sample as acknowledged.

void astutedds::rtps::WriterHistoryCache::mark_acknowledged (
    const SequenceNumber_t & seq_num
) 

Parameters:

• seq_num Sequence number to mark

---

function mark_acknowledged_up_to

Mark all samples up to a sequence number as acknowledged.

void astutedds::rtps::WriterHistoryCache::mark_acknowledged_up_to (
    const SequenceNumber_t & up_to_seq_num
) 

Parameters:

• up_to_seq_num Acknowledge all samples up to and including this

---

function remove_older_than

Remove samples older than a certain age.

void astutedds::rtps::WriterHistoryCache::remove_older_than (
    std::chrono::milliseconds max_age
) 

Parameters:

• max_age Maximum age to keep

---

function size

Get number of samples in cache.

size_t astutedds::rtps::WriterHistoryCache::size () const

Returns:

Sample count

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The documentation for this class was generated from the following file include/astutedds/rtps/writer_history_cache.hpp