/* * BIRD Library -- Event Processing * * (c) 1999 Martin Mares <mj@ucw.cz> * * Can be freely distributed and used under the terms of the GNU GPL. */ #ifndef _BIRD_EVENT_H_ #define _BIRD_EVENT_H_ #include "lib/resource.h" #include "lib/locking.h" #include <stdatomic.h> struct birdloop; typedef struct event { resource r; void (*hook)(void *); void *data; struct event * _Atomic next; } event; typedef union event_list { struct { event * _Atomic receiver; /* Event receive list */ event * _Atomic _executor; /* Event execute list */ const char *name; struct birdloop *loop; /* The executor loop */ char _end[0]; }; event _sentinel; /* Sentinel node to actively detect list end */ } event_list; extern event_list global_event_list; extern event_list global_work_list; event *ev_new(pool *); void ev_run(event *); void ev_init_list(event_list *, struct birdloop *loop, const char *name); void ev_enqueue(event_list *, event *); #define ev_send ev_enqueue #define ev_send_loop(l, e) ev_send(birdloop_event_list((l)), (e)) #define ev_schedule(e) ({ ASSERT_THE_BIRD_LOCKED; if (!ev_active((e))) ev_send(&global_event_list, (e)); }) #define ev_schedule_work(e) ({ ASSERT_THE_BIRD_LOCKED; if (!ev_active((e))) ev_send(&global_work_list, (e)); }) void ev_postpone(event *); int ev_run_list_limited(event_list *, uint); #define ev_run_list(l) ev_run_list_limited((l), ~0) #define LEGACY_EVENT_LIST(l) (((l) == &global_event_list) || ((l) == &global_work_list)) static inline int ev_active(event *e) { return atomic_load_explicit(&e->next, memory_order_relaxed) != NULL; } static inline event_list * ev_get_list(event *e) { /* We are looking for the sentinel node at the list end. * After this, we have s->next == NULL */ event *s = e; for (event *sn; sn = atomic_load_explicit(&s->next, memory_order_acquire); s = sn) ; /* No sentinel, no list. */ if (s == e) return NULL; else return SKIP_BACK(event_list, _sentinel, s); } static inline event* ev_new_init(pool *p, void (*hook)(void *), void *data) { event *e = ev_new(p); e->hook = hook; e->data = data; return e; } #endif