Struct SampleInfo 

pub struct SampleInfo {
    pub sample_state: SampleStateKind,
    pub view_state: ViewStateKind,
    pub instance_state: InstanceStateKind,
    pub disposed_generation_count: i32,
    pub no_writers_generation_count: i32,
    pub sample_rank: i32,
    pub generation_rank: i32,
    pub absolute_generation_rank: i32,
    pub source_timestamp: Time,
    pub instance_handle: InstanceHandle,
    pub publication_handle: InstanceHandle,
    pub valid_data: bool,
}

SampleInfo (DDS 1.4 §2.2.2.5.1) — per-sample metadata.

Filled by the DataReader in the take/read path. Application code is meant to rely on these fields to:

• distinguish new samples from re-read ones (sample_state),
• detect new instances (view_state == NEW),
• observe lifecycle events (instance_state, valid_data == false),
• follow reordering / generation changes (*_generation_count, *_rank).

Fields

sample_state: SampleStateKind

Sample-State (READ / NOT_READ).

view_state: ViewStateKind

View-State (NEW / NOT_NEW).

instance_state: InstanceStateKind

Instance-State (ALIVE / NOT_ALIVE_*).

disposed_generation_count: i32

How many times the instance has gone through NOT_ALIVE_DISPOSED → ALIVE since its first sample.

no_writers_generation_count: i32

How many times the instance has gone through NOT_ALIVE_NO_WRITERS → ALIVE since its first sample.

sample_rank: i32

Number of samples in the same instance that follow this one in the cache (§2.2.2.5.1.5).

generation_rank: i32

Difference in generation_count between this sample and the last sample of the instance in the same read set.

absolute_generation_rank: i32

Difference in generation_count between this sample and the current generation count.

source_timestamp: Time

Wall-clock time of the write/dispose/unregister.

instance_handle: InstanceHandle

Local handle of the instance.

publication_handle: InstanceHandle

Local handle of the sending DataWriter (HANDLE_NIL in the offline / unknown case).

valid_data: bool

true if the sample carries payload; false for a plain dispose/unregister marker (§2.2.2.5.1.13).

Implementations

impl SampleInfo

pub fn new_alive( instance: InstanceHandle, publication: InstanceHandle, timestamp: Time, ) -> Self

Constructs a default info block for a fresh sample of a new instance with valid_data = true.

pub fn matches_states( &self, sample_mask: u32, view_mask: u32, instance_mask: u32, ) -> bool

Checks whether this SampleInfo is accepted by the given state masks (spec §2.2.2.5.3.1, read_w_condition).

Trait Implementations

impl Clone for SampleInfo

fn clone(&self) -> SampleInfo

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for SampleInfo

impl Debug for SampleInfo

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for SampleInfo

fn default() -> Self

Returns the “default value” for a type.

impl Eq for SampleInfo

impl PartialEq for SampleInfo

fn eq(&self, other: &SampleInfo) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for SampleInfo