rmw_event.h

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#ifndef NROS_RMW_EVENT_H
#define NROS_RMW_EVENT_H
 
#include <stdint.h>
#include <stddef.h>
 
#include "nros/rmw_ret.h"
 
typedef enum rmw_event_type_t {
    NROS_RMW_EVENT_LIVELINESS_CHANGED         = 0,
    NROS_RMW_EVENT_REQUESTED_DEADLINE_MISSED  = 1,
    NROS_RMW_EVENT_MESSAGE_LOST               = 2,
    NROS_RMW_EVENT_LIVELINESS_LOST            = 3,
    NROS_RMW_EVENT_OFFERED_DEADLINE_MISSED    = 4,
} rmw_event_type_t;
 
typedef struct rmw_liveliness_changed_status_t {
    uint16_t alive_count;
    uint16_t not_alive_count;
    int16_t  alive_count_change;
    int16_t  not_alive_count_change;
} rmw_liveliness_changed_status_t;
 
typedef struct rmw_count_status_t {
    uint32_t total_count;
    uint32_t total_count_change;
} rmw_count_status_t;
 
typedef union rmw_event_payload_t {
    rmw_liveliness_changed_status_t liveliness_changed;
    rmw_count_status_t              count;
} rmw_event_payload_t;
 
/* Phase 376 W5 — `rmw_status_event_callback_t`, NOT `rmw_event_callback_t`.
 *
 * Upstream binds `rmw_event_callback_t` to a DIFFERENT signature —
 * `void(const void *user_data, size_t number_of_events)`, the callback
 * `rmw_{service,client,subscription}_set_on_new_*_callback` install. Ours is
 * the DDS STATUS-event callback: a kind, a payload union, and a context.
 *
 * Two types of one name whose shapes disagree is exactly the hazard
 * `rmw_vtable.h`'s `#error` guard exists for — except this one would have been
 * INSIDE our own header, where the guard cannot see it, and
 * `scripts/rmw-abi-shape.py` compares parameter type NAMES, so it would have
 * reported the `set_on_new_*` slots as matching upstream exactly while they
 * took a callback of the wrong shape. Introduced by W3.a's rename; caught by
 * the W5 audit before any slot depended on it. */
typedef void (*rmw_status_event_callback_t)(
    rmw_event_type_t            kind,
    const rmw_event_payload_t  *payload,
    void                            *user_context);
 
 
typedef void (*rmw_event_callback_t)(const void *user_data, size_t number_of_events);
 
#endif /* NROS_RMW_EVENT_H */