Edit
kc3-lang/libevent/event.c
Nick Mathewson
- event.c
-
/* * Copyright (c) 2000-2007 Niels Provos <provos@citi.umich.edu> * Copyright (c) 2007-2010 Niels Provos and Nick Mathewson * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include "event-config.h" #ifdef WIN32 #include <winsock2.h> #define WIN32_LEAN_AND_MEAN #include <windows.h> #undef WIN32_LEAN_AND_MEAN #endif #include <sys/types.h> #if !defined(WIN32) && defined(_EVENT_HAVE_SYS_TIME_H) #include <sys/time.h> #endif #include <sys/queue.h> #ifdef _EVENT_HAVE_SYS_SOCKET_H #include <sys/socket.h> #endif #include <stdio.h> #include <stdlib.h> #ifdef _EVENT_HAVE_UNISTD_H #include <unistd.h> #endif #ifdef _EVENT_HAVE_SYS_EVENTFD_H #include <sys/eventfd.h> #endif #include <ctype.h> #include <errno.h> #include <signal.h> #include <string.h> #include <time.h> #include "event2/event.h" #include "event2/event_struct.h" #include "event2/event_compat.h" #include "event-internal.h" #include "defer-internal.h" #include "evthread-internal.h" #include "event2/thread.h" #include "event2/util.h" #include "log-internal.h" #include "evmap-internal.h" #include "iocp-internal.h" #include "changelist-internal.h" #include "ht-internal.h" #ifdef _EVENT_HAVE_EVENT_PORTS extern const struct eventop evportops; #endif #ifdef _EVENT_HAVE_SELECT extern const struct eventop selectops; #endif #ifdef _EVENT_HAVE_POLL extern const struct eventop pollops; #endif #ifdef _EVENT_HAVE_EPOLL extern const struct eventop epollops; #endif #ifdef _EVENT_HAVE_WORKING_KQUEUE extern const struct eventop kqops; #endif #ifdef _EVENT_HAVE_DEVPOLL extern const struct eventop devpollops; #endif #ifdef WIN32 extern const struct eventop win32ops; #endif /* Array of backends in order of preference. */ static const struct eventop *eventops[] = { #ifdef _EVENT_HAVE_EVENT_PORTS &evportops, #endif #ifdef _EVENT_HAVE_WORKING_KQUEUE &kqops, #endif #ifdef _EVENT_HAVE_EPOLL &epollops, #endif #ifdef _EVENT_HAVE_DEVPOLL &devpollops, #endif #ifdef _EVENT_HAVE_POLL &pollops, #endif #ifdef _EVENT_HAVE_SELECT &selectops, #endif #ifdef WIN32 &win32ops, #endif NULL }; /* Global state; deprecated */ struct event_base *current_base = NULL; /* Global state */ extern struct event_base *evsig_base; static int use_monotonic; /* Prototypes */ static inline int event_add_internal(struct event *ev, const struct timeval *tv, int tv_is_absolute); static inline int event_del_internal(struct event *ev); static void event_queue_insert(struct event_base *, struct event *, int); static void event_queue_remove(struct event_base *, struct event *, int); static int event_haveevents(struct event_base *); static void event_process_active(struct event_base *); static int timeout_next(struct event_base *, struct timeval **); static void timeout_process(struct event_base *); static void timeout_correct(struct event_base *, struct timeval *); static inline void event_signal_closure(struct event_base *, struct event *ev); static inline void event_persist_closure(struct event_base *, struct event *ev); static int evthread_notify_base(struct event_base *base); #ifndef _EVENT_DISABLE_DEBUG_MODE /* These functions implement a hashtable of which 'struct event *' structures * have been setup or added. We don't want to trust the content of the struct * event itself, since we're trying to work through cases where an event gets * clobbered or freed. Instead, we keep a hashtable indexed by the pointer. */ struct event_debug_entry { HT_ENTRY(event_debug_entry) node; const struct event *ptr; unsigned added : 1; }; static inline unsigned hash_debug_entry(const struct event_debug_entry *e) { /* We need to do this silliness to convince compilers that we * honestly mean to cast e->ptr to an integer, and discard any * part of it that doesn't fit in an unsigned. */ unsigned u = (unsigned) ((ev_uintptr_t) e->ptr); /* Our hashtable implementation is pretty sensitive to low bits, * and every struct event is over 64 bytes in size, so we can * just say >>6. */ return (u >> 6); } static inline int eq_debug_entry(const struct event_debug_entry *a, const struct event_debug_entry *b) { return a->ptr == b->ptr; } int _event_debug_mode_on = 0; static void *_event_debug_map_lock = NULL; static HT_HEAD(event_debug_map, event_debug_entry) global_debug_map = HT_INITIALIZER(); HT_PROTOTYPE(event_debug_map, event_debug_entry, node, hash_debug_entry, eq_debug_entry); HT_GENERATE(event_debug_map, event_debug_entry, node, hash_debug_entry, eq_debug_entry, 0.5, mm_malloc, mm_realloc, mm_free); /* Macro: record that ev is now setup (that is, ready for an add) */ #define _event_debug_note_setup(ev) do { \ if (_event_debug_mode_on) { \ struct event_debug_entry *dent,find; \ find.ptr = (ev); \ EVLOCK_LOCK(_event_debug_map_lock, 0); \ dent = HT_FIND(event_debug_map, &global_debug_map, &find); \ if (dent) { \ dent->added = 0; \ } else { \ dent = mm_malloc(sizeof(*dent)); \ if (!dent) \ event_err(1, \ "Out of memory in debugging code"); \ dent->ptr = (ev); \ dent->added = 0; \ HT_INSERT(event_debug_map, &global_debug_map, dent); \ } \ EVLOCK_UNLOCK(_event_debug_map_lock, 0); \ } \ } while (0) /* Macro: record that ev is no longer setup */ #define _event_debug_note_teardown(ev) do { \ if (_event_debug_mode_on) { \ struct event_debug_entry *dent,find; \ find.ptr = (ev); \ EVLOCK_LOCK(_event_debug_map_lock, 0); \ dent = HT_REMOVE(event_debug_map, &global_debug_map, &find); \ if (dent) \ mm_free(dent); \ EVLOCK_UNLOCK(_event_debug_map_lock, 0); \ } \ } while (0) /* Macro: record that ev is now added */ #define _event_debug_note_add(ev) do { \ if (_event_debug_mode_on) { \ struct event_debug_entry *dent,find; \ find.ptr = (ev); \ EVLOCK_LOCK(_event_debug_map_lock, 0); \ dent = HT_FIND(event_debug_map, &global_debug_map, &find); \ if (dent) { \ dent->added = 1; \ } else { \ event_errx(_EVENT_ERR_ABORT, \ "%s: noting an add on a non-setup event %p", \ __func__, (ev)); \ } \ EVLOCK_UNLOCK(_event_debug_map_lock, 0); \ } \ } while (0) /* Macro: record that ev is no longer added */ #define _event_debug_note_del(ev) do { \ if (_event_debug_mode_on) { \ struct event_debug_entry *dent,find; \ find.ptr = (ev); \ EVLOCK_LOCK(_event_debug_map_lock, 0); \ dent = HT_FIND(event_debug_map, &global_debug_map, &find); \ if (dent) { \ dent->added = 0; \ } else { \ event_errx(_EVENT_ERR_ABORT, \ "%s: noting a del on a non-setup event %p", \ __func__, (ev)); \ } \ EVLOCK_UNLOCK(_event_debug_map_lock, 0); \ } \ } while (0) /* Macro: assert that ev is setup (i.e., okay to add or inspect) */ #define _event_debug_assert_is_setup(ev) do { \ if (_event_debug_mode_on) { \ struct event_debug_entry *dent,find; \ find.ptr = (ev); \ EVLOCK_LOCK(_event_debug_map_lock, 0); \ dent = HT_FIND(event_debug_map, &global_debug_map, &find); \ if (!dent) { \ event_errx(_EVENT_ERR_ABORT, \ "%s called on a non-initialized event %p", \ __func__, (ev)); \ } \ EVLOCK_UNLOCK(_event_debug_map_lock, 0); \ } \ } while (0) /* Macro: assert that ev is not added (i.e., okay to tear down or set * up again) */ #define _event_debug_assert_not_added(ev) do { \ if (_event_debug_mode_on) { \ struct event_debug_entry *dent,find; \ find.ptr = (ev); \ EVLOCK_LOCK(_event_debug_map_lock, 0); \ dent = HT_FIND(event_debug_map, &global_debug_map, &find); \ if (dent && dent->added) { \ event_errx(_EVENT_ERR_ABORT, \ "%s called on an already added event %p", \ __func__, (ev)); \ } \ EVLOCK_UNLOCK(_event_debug_map_lock, 0); \ } \ } while (0) #else #define _event_debug_note_setup(ev) \ ((void)0) #define _event_debug_note_teardown(ev) \ ((void)0) #define _event_debug_note_add(ev) \ ((void)0) #define _event_debug_note_del(ev) \ ((void)0) #define _event_debug_assert_is_setup(ev) \ ((void)0) #define _event_debug_assert_not_added(ev) \ ((void)0) #endif #define EVENT_BASE_ASSERT_LOCKED(base) \ EVLOCK_ASSERT_LOCKED((base)->th_base_lock) /* The first time this function is called, it sets use_monotonic to 1 * if we have a clock function that supports monotonic time */ static void detect_monotonic(void) { #if defined(_EVENT_HAVE_CLOCK_GETTIME) && defined(CLOCK_MONOTONIC) struct timespec ts; static int use_monotonic_initialized = 0; if (use_monotonic_initialized) return; if (clock_gettime(CLOCK_MONOTONIC, &ts) == 0) use_monotonic = 1; use_monotonic_initialized = 1; #endif } /** Set 'tp' to the current time according to 'base'. We must hold the lock * on 'base'. If there is a cached time, return it. Otherwise, use * clock_gettime or gettimeofday as appropriate to find out the right time. * Return 0 on success, -1 on failure. */ static int gettime(struct event_base *base, struct timeval *tp) { EVENT_BASE_ASSERT_LOCKED(base); if (base->tv_cache.tv_sec) { *tp = base->tv_cache; return (0); } #if defined(_EVENT_HAVE_CLOCK_GETTIME) && defined(CLOCK_MONOTONIC) if (use_monotonic) { struct timespec ts; if (clock_gettime(CLOCK_MONOTONIC, &ts) == -1) return (-1); tp->tv_sec = ts.tv_sec; tp->tv_usec = ts.tv_nsec / 1000; return (0); } #endif return (evutil_gettimeofday(tp, NULL)); } int event_base_gettimeofday_cached(struct event_base *base, struct timeval *tv) { int r; if (!base) { base = current_base; if (!current_base) return evutil_gettimeofday(tv, NULL); } EVBASE_ACQUIRE_LOCK(base, th_base_lock); r = gettime(base, tv); EVBASE_RELEASE_LOCK(base, th_base_lock); return r; } /** Make 'base' have no current cached time. */ static inline void clear_time_cache(struct event_base *base) { base->tv_cache.tv_sec = 0; } /** Replace the cached time in 'base' with the current time. */ static inline void update_time_cache(struct event_base *base) { base->tv_cache.tv_sec = 0; if (!(base->flags & EVENT_BASE_FLAG_NO_CACHE_TIME)) gettime(base, &base->tv_cache); } struct event_base * event_init(void) { struct event_base *base = event_base_new_with_config(NULL); if (base == NULL) { event_errx(1, "%s: Unable to construct event_base", __func__); return NULL; } current_base = base; return (base); } struct event_base * event_base_new(void) { struct event_base *base = NULL; struct event_config *cfg = event_config_new(); if (cfg) { base = event_base_new_with_config(cfg); event_config_free(cfg); } return base; } /** Return true iff 'method' is the name of a method that 'cfg' tells us to * avoid. */ static int event_config_is_avoided_method(const struct event_config *cfg, const char *method) { struct event_config_entry *entry; TAILQ_FOREACH(entry, &cfg->entries, next) { if (entry->avoid_method != NULL && strcmp(entry->avoid_method, method) == 0) return (1); } return (0); } /** Return true iff 'method' is disabled according to the environment. */ static int event_is_method_disabled(const char *name) { char environment[64]; int i; evutil_snprintf(environment, sizeof(environment), "EVENT_NO%s", name); for (i = 8; environment[i] != '\0'; ++i) environment[i] = toupper(environment[i]); /* Note that evutil_getenv() ignores the environment entirely if * we're setuid */ return (evutil_getenv(environment) != NULL); } int event_base_get_features(const struct event_base *base) { return base->evsel->features; } void event_deferred_cb_queue_init(struct deferred_cb_queue *cb) { memset(cb, 0, sizeof(struct deferred_cb_queue)); TAILQ_INIT(&cb->deferred_cb_list); } /** Helper for the deferred_cb queue: wake up the event base. */ static void notify_base_cbq_callback(struct deferred_cb_queue *cb, void *baseptr) { struct event_base *base = baseptr; if (!EVBASE_IN_THREAD(base)) evthread_notify_base(base); } struct deferred_cb_queue * event_base_get_deferred_cb_queue(struct event_base *base) { return base ? &base->defer_queue : NULL; } void event_enable_debug_mode(void) { #ifndef _EVENT_DISABLE_DEBUG_MODE if (_event_debug_mode_on) event_errx(1, "%s was called twice!", __func__); _event_debug_mode_on = 1; HT_INIT(event_debug_map, &global_debug_map); EVTHREAD_ALLOC_LOCK(_event_debug_map_lock, 0); #endif } #if 0 void event_disable_debug_mode(void) { struct event_debug_entry **ent, *victim; EVLOCK_LOCK(_event_debug_map_lock, 0); for (ent = HT_START(event_debug_map, &global_debug_map); ent; ) { victim = *ent; ent = HT_NEXT_RMV(event_debug_map,&global_debug_map, ent); mm_free(victim); } HT_CLEAR(event_debug_map, &global_debug_map); EVLOCK_UNLOCK(_event_debug_map_lock , 0); } #endif struct event_base * event_base_new_with_config(const struct event_config *cfg) { int i; struct event_base *base; int should_check_environment; #ifndef _EVENT_DISABLE_DEBUG_MODE if (_event_debug_mode_on && !_event_debug_map_lock) { EVTHREAD_ALLOC_LOCK(_event_debug_map_lock, 0); } #endif if ((base = mm_calloc(1, sizeof(struct event_base))) == NULL) { event_warn("%s: calloc", __func__); return NULL; } detect_monotonic(); gettime(base, &base->event_tv); min_heap_ctor(&base->timeheap); TAILQ_INIT(&base->eventqueue); base->sig.ev_signal_pair[0] = -1; base->sig.ev_signal_pair[1] = -1; event_deferred_cb_queue_init(&base->defer_queue); base->defer_queue.notify_fn = notify_base_cbq_callback; base->defer_queue.notify_arg = base; if (cfg) base->flags = cfg->flags; evmap_io_initmap(&base->io); evmap_signal_initmap(&base->sigmap); event_changelist_init(&base->changelist); base->evbase = NULL; should_check_environment = !(cfg && (cfg->flags & EVENT_BASE_FLAG_IGNORE_ENV)); for (i = 0; eventops[i] && !base->evbase; i++) { if (cfg != NULL) { /* determine if this backend should be avoided */ if (event_config_is_avoided_method(cfg, eventops[i]->name)) continue; if ((eventops[i]->features & cfg->require_features) != cfg->require_features) continue; } /* also obey the environment variables */ if (should_check_environment && event_is_method_disabled(eventops[i]->name)) continue; base->evsel = eventops[i]; base->evbase = base->evsel->init(base); } if (base->evbase == NULL) { event_warnx("%s: no event mechanism available", __func__); event_base_free(base); return NULL; } if (evutil_getenv("EVENT_SHOW_METHOD")) event_msgx("libevent using: %s", base->evsel->name); /* allocate a single active event queue */ if (event_base_priority_init(base, 1) < 0) { event_base_free(base); return NULL; } /* prepare for threading */ base->th_notify_fd[0] = -1; base->th_notify_fd[1] = -1; #ifndef _EVENT_DISABLE_THREAD_SUPPORT if (!cfg || !(cfg->flags & EVENT_BASE_FLAG_NOLOCK)) { int r; EVTHREAD_ALLOC_LOCK(base->th_base_lock, EVTHREAD_LOCKTYPE_RECURSIVE); base->defer_queue.lock = base->th_base_lock; EVTHREAD_ALLOC_LOCK(base->current_event_lock, EVTHREAD_LOCKTYPE_RECURSIVE); r = evthread_make_base_notifiable(base); if (r<0) { event_base_free(base); return NULL; } } #endif #ifdef WIN32 if (cfg && (cfg->flags & EVENT_BASE_FLAG_STARTUP_IOCP)) event_base_start_iocp(base); #endif return (base); } int event_base_start_iocp(struct event_base *base) { #ifdef WIN32 if (base->iocp) return 0; base->iocp = event_iocp_port_launch(); if (!base->iocp) { event_warnx("%s: Couldn't launch IOCP", __func__); return -1; } return 0; #else return -1; #endif } void event_base_free(struct event_base *base) { int i, n_deleted=0; struct event *ev; /* XXXX grab the lock? If there is contention when one thread frees * the base, then the contending thread will be very sad soon. */ if (base == NULL && current_base) base = current_base; if (base == current_base) current_base = NULL; /* XXX(niels) - check for internal events first */ EVUTIL_ASSERT(base); /* threading fds if we have them */ if (base->th_notify_fd[0] != -1) { event_del(&base->th_notify); EVUTIL_CLOSESOCKET(base->th_notify_fd[0]); if (base->th_notify_fd[1] != -1) EVUTIL_CLOSESOCKET(base->th_notify_fd[1]); base->th_notify_fd[0] = -1; base->th_notify_fd[1] = -1; event_debug_unassign(&base->th_notify); } /* Delete all non-internal events. */ for (ev = TAILQ_FIRST(&base->eventqueue); ev; ) { struct event *next = TAILQ_NEXT(ev, ev_next); if (!(ev->ev_flags & EVLIST_INTERNAL)) { event_del(ev); ++n_deleted; } ev = next; } while ((ev = min_heap_top(&base->timeheap)) != NULL) { event_del(ev); ++n_deleted; } for (i = 0; i < base->n_common_timeouts; ++i) { struct common_timeout_list *ctl = base->common_timeout_queues[i]; event_del(&ctl->timeout_event); /* Internal; doesn't count */ event_debug_unassign(&ctl->timeout_event); for (ev = TAILQ_FIRST(&ctl->events); ev; ) { struct event *next = TAILQ_NEXT(ev, ev_timeout_pos.ev_next_with_common_timeout); if (!(ev->ev_flags & EVLIST_INTERNAL)) { event_del(ev); ++n_deleted; } ev = next; } mm_free(ctl); } if (base->common_timeout_queues) mm_free(base->common_timeout_queues); for (i = 0; i < base->nactivequeues; ++i) { for (ev = TAILQ_FIRST(&base->activequeues[i]); ev; ) { struct event *next = TAILQ_NEXT(ev, ev_active_next); if (!(ev->ev_flags & EVLIST_INTERNAL)) { event_del(ev); ++n_deleted; } ev = next; } } if (n_deleted) event_debug(("%s: %d events were still set in base", __func__, n_deleted)); if (base->evsel != NULL && base->evsel->dealloc != NULL) base->evsel->dealloc(base); for (i = 0; i < base->nactivequeues; ++i) EVUTIL_ASSERT(TAILQ_EMPTY(&base->activequeues[i])); EVUTIL_ASSERT(min_heap_empty(&base->timeheap)); min_heap_dtor(&base->timeheap); mm_free(base->activequeues); EVUTIL_ASSERT(TAILQ_EMPTY(&base->eventqueue)); evmap_io_clear(&base->io); evmap_signal_clear(&base->sigmap); event_changelist_freemem(&base->changelist); EVTHREAD_FREE_LOCK(base->th_base_lock, EVTHREAD_LOCKTYPE_RECURSIVE); EVTHREAD_FREE_LOCK(base->current_event_lock, EVTHREAD_LOCKTYPE_RECURSIVE); mm_free(base); } /* reinitialize the event base after a fork */ int event_reinit(struct event_base *base) { const struct eventop *evsel; int res = 0; struct event *ev; EVBASE_ACQUIRE_LOCK(base, th_base_lock); evsel = base->evsel; /* check if this event mechanism requires reinit */ if (!evsel->need_reinit) goto done; /* prevent internal delete */ if (base->sig.ev_signal_added) { /* we cannot call event_del here because the base has * not been reinitialized yet. */ event_queue_remove(base, &base->sig.ev_signal, EVLIST_INSERTED); if (base->sig.ev_signal.ev_flags & EVLIST_ACTIVE) event_queue_remove(base, &base->sig.ev_signal, EVLIST_ACTIVE); base->sig.ev_signal_added = 0; } if (base->evsel->dealloc != NULL) base->evsel->dealloc(base); base->evbase = evsel->init(base); if (base->evbase == NULL) { event_errx(1, "%s: could not reinitialize event mechanism", __func__); res = -1; goto done; } event_changelist_freemem(&base->changelist); /* XXX */ evmap_io_clear(&base->io); evmap_signal_clear(&base->sigmap); TAILQ_FOREACH(ev, &base->eventqueue, ev_next) { if (ev->ev_events & (EV_READ|EV_WRITE)) { if (evmap_io_add(base, ev->ev_fd, ev) == -1) res = -1; } else if (ev->ev_events & EV_SIGNAL) { if (evmap_signal_add(base, ev->ev_fd, ev) == -1) res = -1; } } done: EVBASE_RELEASE_LOCK(base, th_base_lock); return (res); } const char ** event_get_supported_methods(void) { static const char **methods = NULL; const struct eventop **method; const char **tmp; int i = 0, k; /* count all methods */ for (method = &eventops[0]; *method != NULL; ++method) { ++i; } /* allocate one more than we need for the NULL pointer */ tmp = mm_calloc((i + 1), sizeof(char *)); if (tmp == NULL) return (NULL); /* populate the array with the supported methods */ for (k = 0, i = 0; eventops[k] != NULL; ++k) { tmp[i++] = eventops[k]->name; } tmp[i] = NULL; if (methods != NULL) mm_free((char**)methods); methods = tmp; return (methods); } struct event_config * event_config_new(void) { struct event_config *cfg = mm_calloc(1, sizeof(*cfg)); if (cfg == NULL) return (NULL); TAILQ_INIT(&cfg->entries); return (cfg); } static void event_config_entry_free(struct event_config_entry *entry) { if (entry->avoid_method != NULL) mm_free((char *)entry->avoid_method); mm_free(entry); } void event_config_free(struct event_config *cfg) { struct event_config_entry *entry; while ((entry = TAILQ_FIRST(&cfg->entries)) != NULL) { TAILQ_REMOVE(&cfg->entries, entry, next); event_config_entry_free(entry); } mm_free(cfg); } int event_config_set_flag(struct event_config *cfg, int flag) { if (!cfg) return -1; cfg->flags |= flag; return 0; } int event_config_avoid_method(struct event_config *cfg, const char *method) { struct event_config_entry *entry = mm_malloc(sizeof(*entry)); if (entry == NULL) return (-1); if ((entry->avoid_method = mm_strdup(method)) == NULL) { mm_free(entry); return (-1); } TAILQ_INSERT_TAIL(&cfg->entries, entry, next); return (0); } int event_config_require_features(struct event_config *cfg, int features) { if (!cfg) return (-1); cfg->require_features = features; return (0); } int event_priority_init(int npriorities) { return event_base_priority_init(current_base, npriorities); } int event_base_priority_init(struct event_base *base, int npriorities) { int i; if (N_ACTIVE_CALLBACKS(base) || npriorities < 1 || npriorities >= EVENT_MAX_PRIORITIES) return (-1); if (npriorities == base->nactivequeues) return (0); if (base->nactivequeues) { mm_free(base->activequeues); base->nactivequeues = 0; } /* Allocate our priority queues */ base->activequeues = (struct event_list *) mm_calloc(npriorities, sizeof(struct event_list)); if (base->activequeues == NULL) { event_warn("%s: calloc", __func__); return (-1); } base->nactivequeues = npriorities; for (i = 0; i < base->nactivequeues; ++i) { TAILQ_INIT(&base->activequeues[i]); } return (0); } /* Returns true iff we're currently watching any events. */ static int event_haveevents(struct event_base *base) { /* Caller must hold th_base_lock */ return (base->event_count > 0); } /* "closure" function called when processing active signal events */ static inline void event_signal_closure(struct event_base *base, struct event *ev) { short ncalls; /* Allows deletes to work */ ncalls = ev->ev_ncalls; ev->ev_pncalls = &ncalls; EVBASE_RELEASE_LOCK(base, th_base_lock); while (ncalls) { ncalls--; ev->ev_ncalls = ncalls; (*ev->ev_callback)((int)ev->ev_fd, ev->ev_res, ev->ev_arg); #if 0 /* XXXX we can't do this without a lock on the base. */ if (base->event_break) return; #endif } } /* Common timeouts are special timeouts that are handled as queues rather than * in the minheap. This is more efficient than the minheap if we happen to * know that we're going to get several thousands of timeout events all with * the same timeout value. * * Since all our timeout handling code assumes timevals can be copied, * assigned, etc, we can't use "magic pointer" to encode these common * timeouts. Searching through a list to see if every timeout is common could * also get inefficient. Instead, we take advantage of the fact that tv_usec * is 32 bits long, but only uses 20 of those bits (since it can never be over * 999999.) We use the top bits to encode 4 bites of magic number, and 8 bits * of index into the event_base's aray of common timeouts. */ #define MICROSECONDS_MASK 0x000fffff #define COMMON_TIMEOUT_IDX_MASK 0x0ff00000 #define COMMON_TIMEOUT_IDX_SHIFT 20 #define COMMON_TIMEOUT_MASK 0xf0000000 #define COMMON_TIMEOUT_MAGIC 0x50000000 #define COMMON_TIMEOUT_IDX(tv) \ (((tv)->tv_usec & COMMON_TIMEOUT_IDX_MASK)>>COMMON_TIMEOUT_IDX_SHIFT) /** Return true iff if 'tv' is a common timeout in 'base' */ static inline int is_common_timeout(const struct timeval *tv, const struct event_base *base) { int idx; if ((tv->tv_usec & COMMON_TIMEOUT_MASK) != COMMON_TIMEOUT_MAGIC) return 0; idx = COMMON_TIMEOUT_IDX(tv); return idx < base->n_common_timeouts; } /* True iff tv1 and tv2 have the same common-timeout index, or if neither * one is a common timeout. */ static inline int is_same_common_timeout(const struct timeval *tv1, const struct timeval *tv2) { return (tv1->tv_usec & ~MICROSECONDS_MASK) == (tv2->tv_usec & ~MICROSECONDS_MASK); } /** Requires that 'tv' is a common timeout. Return the corresponding * common_timeout_list. */ static inline struct common_timeout_list * get_common_timeout_list(struct event_base *base, const struct timeval *tv) { return base->common_timeout_queues[COMMON_TIMEOUT_IDX(tv)]; } #if 0 static inline int common_timeout_ok(const struct timeval *tv, struct event_base *base) { const struct timeval *expect = &get_common_timeout_list(base, tv)->duration; return tv->tv_sec == expect->tv_sec && tv->tv_usec == expect->tv_usec; } #endif /* Add the timeout for the first event in given common timeout list to the * event_base's minheap. */ static void common_timeout_schedule(struct common_timeout_list *ctl, const struct timeval *now, struct event *head) { struct timeval timeout = head->ev_timeout; timeout.tv_usec &= MICROSECONDS_MASK; event_add_internal(&ctl->timeout_event, &timeout, 1); } /* Callback: invoked when the timeout for a common timeout queue triggers. * This means that (at least) the first event in that queue should be run, * and the timeout should be rescheduled if there are more events. */ static void common_timeout_callback(evutil_socket_t fd, short what, void *arg) { struct timeval now; struct common_timeout_list *ctl = arg; struct event_base *base = ctl->base; struct event *ev = NULL; EVBASE_ACQUIRE_LOCK(base, th_base_lock); gettime(base, &now); while (1) { ev = TAILQ_FIRST(&ctl->events); if (!ev || ev->ev_timeout.tv_sec > now.tv_sec || (ev->ev_timeout.tv_sec == now.tv_sec && (ev->ev_timeout.tv_usec&MICROSECONDS_MASK) > now.tv_usec)) break; event_del_internal(ev); event_active_nolock(ev, EV_TIMEOUT, 1); } if (ev) common_timeout_schedule(ctl, &now, ev); EVBASE_RELEASE_LOCK(base, th_base_lock); } #define MAX_COMMON_TIMEOUTS 256 const struct timeval * event_base_init_common_timeout(struct event_base *base, const struct timeval *duration) { int i; struct timeval tv; const struct timeval *result=NULL; struct common_timeout_list *new_ctl; EVBASE_ACQUIRE_LOCK(base, th_base_lock); if (duration->tv_usec > 1000000) { memcpy(&tv, duration, sizeof(struct timeval)); if (is_common_timeout(duration, base)) tv.tv_usec &= MICROSECONDS_MASK; tv.tv_sec += tv.tv_usec / 1000000; tv.tv_usec %= 1000000; duration = &tv; } for (i = 0; i < base->n_common_timeouts; ++i) { const struct common_timeout_list *ctl = base->common_timeout_queues[i]; if (duration->tv_sec == ctl->duration.tv_sec && duration->tv_usec == (ctl->duration.tv_usec & MICROSECONDS_MASK)) { EVUTIL_ASSERT(is_common_timeout(&ctl->duration, base)); result = &ctl->duration; goto done; } } if (base->n_common_timeouts == MAX_COMMON_TIMEOUTS) { event_warn("%s: Too many common timeouts already in use; " "we only support %d per event_base", __func__, MAX_COMMON_TIMEOUTS); goto done; } if (base->n_common_timeouts_allocated == base->n_common_timeouts) { int n = base->n_common_timeouts < 16 ? 16 : base->n_common_timeouts*2; struct common_timeout_list **newqueues = mm_realloc(base->common_timeout_queues, n*sizeof(struct common_timeout_queue *)); if (!newqueues) { event_warn("%s: realloc",__func__); goto done; } base->n_common_timeouts_allocated = n; base->common_timeout_queues = newqueues; } new_ctl = mm_calloc(1, sizeof(struct common_timeout_list)); if (!new_ctl) { event_warn("%s: calloc",__func__); goto done; } TAILQ_INIT(&new_ctl->events); new_ctl->duration.tv_sec = duration->tv_sec; new_ctl->duration.tv_usec = duration->tv_usec | COMMON_TIMEOUT_MAGIC | (base->n_common_timeouts << COMMON_TIMEOUT_IDX_SHIFT); evtimer_assign(&new_ctl->timeout_event, base, common_timeout_callback, new_ctl); new_ctl->timeout_event.ev_flags |= EVLIST_INTERNAL; event_priority_set(&new_ctl->timeout_event, 0); new_ctl->base = base; base->common_timeout_queues[base->n_common_timeouts++] = new_ctl; result = &new_ctl->duration; done: if (result) EVUTIL_ASSERT(is_common_timeout(result, base)); EVBASE_RELEASE_LOCK(base, th_base_lock); return result; } /* Closure function invoked when we're activating a persistent event. */ static inline void event_persist_closure(struct event_base *base, struct event *ev) { /* reschedule the persistent event if we have a timeout. */ if (ev->ev_io_timeout.tv_sec || ev->ev_io_timeout.tv_usec) { /* If there was a timeout, we want it to run at an interval of * ev_io_timeout after the last time it was _scheduled_ for, * not ev_io_timeout after _now_. If it fired for another * reason, though, the timeout ought to start ticking _now_. */ struct timeval run_at; EVUTIL_ASSERT(is_same_common_timeout(&ev->ev_timeout, &ev->ev_io_timeout)); if (is_common_timeout(&ev->ev_timeout, base)) { ev_uint32_t usec_mask; struct timeval delay, relative_to; delay = ev->ev_io_timeout; usec_mask = delay.tv_usec & ~MICROSECONDS_MASK; delay.tv_usec &= MICROSECONDS_MASK; if (ev->ev_res & EV_TIMEOUT) { relative_to = ev->ev_timeout; relative_to.tv_usec &= MICROSECONDS_MASK; } else { gettime(base, &relative_to); } evutil_timeradd(&relative_to, &delay, &run_at); run_at.tv_usec |= usec_mask; } else { struct timeval relative_to; if (ev->ev_res & EV_TIMEOUT) { relative_to = ev->ev_timeout; } else { gettime(base, &relative_to); } evutil_timeradd(&ev->ev_io_timeout, &relative_to, &run_at); } event_add_internal(ev, &run_at, 1); } EVBASE_RELEASE_LOCK(base, th_base_lock); (*ev->ev_callback)((int)ev->ev_fd, ev->ev_res, ev->ev_arg); } /* Helper for event_process_active to process all the events in a single queue, releasing the lock as we go. This function requires that the lock be held when it's invoked. Returns -1 if we get a signal or an event_break that means we should stop processing any active events now. Otherwise returns the number of non-internal events that we processed. */ static int event_process_active_single_queue(struct event_base *base, struct event_list *activeq) { struct event *ev; int count = 0; EVUTIL_ASSERT(activeq != NULL); for (ev = TAILQ_FIRST(activeq); ev; ev = TAILQ_FIRST(activeq)) { if (ev->ev_events & EV_PERSIST) event_queue_remove(base, ev, EVLIST_ACTIVE); else event_del_internal(ev); if (!(ev->ev_flags & EVLIST_INTERNAL)) ++count; event_debug(( "event_process_active: event: %p, %s%scall %p", ev, ev->ev_res & EV_READ ? "EV_READ " : " ", ev->ev_res & EV_WRITE ? "EV_WRITE " : " ", ev->ev_callback)); base->current_event = ev; EVBASE_ACQUIRE_LOCK(base, current_event_lock); switch (ev->ev_closure) { case EV_CLOSURE_SIGNAL: event_signal_closure(base, ev); break; case EV_CLOSURE_PERSIST: event_persist_closure(base, ev); break; default: case EV_CLOSURE_NONE: EVBASE_RELEASE_LOCK(base, th_base_lock); (*ev->ev_callback)( (int)ev->ev_fd, ev->ev_res, ev->ev_arg); break; } EVBASE_RELEASE_LOCK(base, current_event_lock); EVBASE_ACQUIRE_LOCK(base, th_base_lock); base->current_event = NULL; if (base->event_break) return -1; } return count; } /* Process all the defered_cb entries in 'queue'. If *breakptr becomes set to 1, stop. Requires that we start out holding the lock on 'queue'; releases the lock around 'queue' for each deferred_cb we process. */ static int event_process_deferred_callbacks(struct deferred_cb_queue *queue, int *breakptr) { int count = 0; struct deferred_cb *cb; while ((cb = TAILQ_FIRST(&queue->deferred_cb_list))) { cb->queued = 0; TAILQ_REMOVE(&queue->deferred_cb_list, cb, cb_next); --queue->active_count; UNLOCK_DEFERRED_QUEUE(queue); cb->cb(cb, cb->arg); ++count; if (*breakptr) return -1; LOCK_DEFERRED_QUEUE(queue); } return count; } /* * Active events are stored in priority queues. Lower priorities are always * process before higher priorities. Low priority events can starve high * priority ones. */ static void event_process_active(struct event_base *base) { /* Caller must hold th_base_lock */ struct event_list *activeq = NULL; int i, c; for (i = 0; i < base->nactivequeues; ++i) { if (TAILQ_FIRST(&base->activequeues[i]) != NULL) { activeq = &base->activequeues[i]; c = event_process_active_single_queue(base, activeq); if (c < 0) return; else if (c > 0) break; /* Processed a real event; do not * consider lower-priority events */ /* If we get here, all of the events we processed * were internal. Continue. */ } } event_process_deferred_callbacks(&base->defer_queue,&base->event_break); } /* * Wait continuously for events. We exit only if no events are left. */ int event_dispatch(void) { return (event_loop(0)); } int event_base_dispatch(struct event_base *event_base) { return (event_base_loop(event_base, 0)); } const char * event_base_get_method(const struct event_base *base) { EVUTIL_ASSERT(base); return (base->evsel->name); } /** Callback: used to implement event_base_loopexit by telling the event_base * that it's time to exit its loop. */ static void event_loopexit_cb(evutil_socket_t fd, short what, void *arg) { struct event_base *base = arg; base->event_gotterm = 1; } int event_loopexit(const struct timeval *tv) { return (event_once(-1, EV_TIMEOUT, event_loopexit_cb, current_base, tv)); } int event_base_loopexit(struct event_base *event_base, const struct timeval *tv) { return (event_base_once(event_base, -1, EV_TIMEOUT, event_loopexit_cb, event_base, tv)); } int event_loopbreak(void) { return (event_base_loopbreak(current_base)); } int event_base_loopbreak(struct event_base *event_base) { if (event_base == NULL) return (-1); EVBASE_ACQUIRE_LOCK(event_base, th_base_lock); event_base->event_break = 1; EVBASE_RELEASE_LOCK(event_base, th_base_lock); if (!EVBASE_IN_THREAD(event_base)) { return evthread_notify_base(event_base); } else { return (0); } } int event_base_got_break(struct event_base *event_base) { int res; EVBASE_ACQUIRE_LOCK(event_base, th_base_lock); res = event_base->event_break; EVBASE_RELEASE_LOCK(event_base, th_base_lock); return res; } int event_base_got_exit(struct event_base *event_base) { int res; EVBASE_ACQUIRE_LOCK(event_base, th_base_lock); res = event_base->event_gotterm; EVBASE_RELEASE_LOCK(event_base, th_base_lock); return res; } /* not thread safe */ int event_loop(int flags) { return event_base_loop(current_base, flags); } int event_base_loop(struct event_base *base, int flags) { const struct eventop *evsel = base->evsel; struct timeval tv; struct timeval *tv_p; int res, done, retval = 0; /* Grab the lock. We will release it inside evsel.dispatch, and again * as we invoke user callbacks. */ EVBASE_ACQUIRE_LOCK(base, th_base_lock); if (base->running_loop) { event_warn("%s: reentrant invocation. Only one event_base_loop" " can run on each event_base at once.", __func__); EVBASE_RELEASE_LOCK(base, th_base_lock); return -1; } base->running_loop = 1; clear_time_cache(base); if (base->sig.ev_signal_added) evsig_base = base; done = 0; #ifndef _EVENT_DISABLE_THREAD_SUPPORT base->th_owner_id = EVTHREAD_GET_ID(); #endif base->event_gotterm = base->event_break = 0; while (!done) { /* Terminate the loop if we have been asked to */ if (base->event_gotterm) { break; } if (base->event_break) { break; } timeout_correct(base, &tv); tv_p = &tv; if (!N_ACTIVE_CALLBACKS(base) && !(flags & EVLOOP_NONBLOCK)) { timeout_next(base, &tv_p); } else { /* * if we have active events, we just poll new events * without waiting. */ evutil_timerclear(&tv); } /* If we have no events, we just exit */ if (!event_haveevents(base) && !N_ACTIVE_CALLBACKS(base)) { event_debug(("%s: no events registered.", __func__)); retval = 1; goto done; } /* update last old time */ gettime(base, &base->event_tv); clear_time_cache(base); res = evsel->dispatch(base, tv_p); if (res == -1) { event_debug(("%s: dispatch returned unsuccessfully.", __func__)); retval = -1; goto done; } update_time_cache(base); timeout_process(base); if (N_ACTIVE_CALLBACKS(base)) { event_process_active(base); if (!base->event_count_active && (flags & EVLOOP_ONCE)) done = 1; } else if (flags & EVLOOP_NONBLOCK) done = 1; } event_debug(("%s: asked to terminate loop.", __func__)); done: clear_time_cache(base); base->running_loop = 0; EVBASE_RELEASE_LOCK(base, th_base_lock); return (retval); } /* Sets up an event for processing once */ struct event_once { struct event ev; void (*cb)(evutil_socket_t, short, void *); void *arg; }; /* One-time callback to implement event_base_once: invokes the user callback, * then deletes the allocated storage */ static void event_once_cb(evutil_socket_t fd, short events, void *arg) { struct event_once *eonce = arg; (*eonce->cb)(fd, events, eonce->arg); event_debug_unassign(&eonce->ev); mm_free(eonce); } /* not threadsafe, event scheduled once. */ int event_once(evutil_socket_t fd, short events, void (*callback)(evutil_socket_t, short, void *), void *arg, const struct timeval *tv) { return event_base_once(current_base, fd, events, callback, arg, tv); } /* Schedules an event once */ int event_base_once(struct event_base *base, evutil_socket_t fd, short events, void (*callback)(evutil_socket_t, short, void *), void *arg, const struct timeval *tv) { struct event_once *eonce; struct timeval etv; int res = 0; /* We cannot support signals that just fire once, or persistent * events. */ if (events & (EV_SIGNAL|EV_PERSIST)) return (-1); if ((eonce = mm_calloc(1, sizeof(struct event_once))) == NULL) return (-1); eonce->cb = callback; eonce->arg = arg; if (events == EV_TIMEOUT) { if (tv == NULL) { evutil_timerclear(&etv); tv = &etv; } evtimer_assign(&eonce->ev, base, event_once_cb, eonce); } else if (events & (EV_READ|EV_WRITE)) { events &= EV_READ|EV_WRITE; event_assign(&eonce->ev, base, fd, events, event_once_cb, eonce); } else { /* Bad event combination */ mm_free(eonce); return (-1); } if (res == 0) res = event_add(&eonce->ev, tv); if (res != 0) { mm_free(eonce); return (res); } return (0); } int event_assign(struct event *ev, struct event_base *base, evutil_socket_t fd, short events, void (*callback)(evutil_socket_t, short, void *), void *arg) { if (!base) base = current_base; _event_debug_assert_not_added(ev); ev->ev_base = base; ev->ev_callback = callback; ev->ev_arg = arg; ev->ev_fd = fd; ev->ev_events = events; ev->ev_res = 0; ev->ev_flags = EVLIST_INIT; ev->ev_ncalls = 0; ev->ev_pncalls = NULL; if (events & EV_SIGNAL) { if ((events & (EV_READ|EV_WRITE)) != 0) { event_warnx("%s: EV_SIGNAL is not compatible with " "EV_READ or EV_WRITE", __func__); return -1; } ev->ev_closure = EV_CLOSURE_SIGNAL; } else { if (events & EV_PERSIST) { evutil_timerclear(&ev->ev_io_timeout); ev->ev_closure = EV_CLOSURE_PERSIST; } else { ev->ev_closure = EV_CLOSURE_NONE; } } min_heap_elem_init(ev); if (base != NULL) { /* by default, we put new events into the middle priority */ ev->ev_pri = base->nactivequeues / 2; } _event_debug_note_setup(ev); return 0; } int event_base_set(struct event_base *base, struct event *ev) { /* Only innocent events may be assigned to a different base */ if (ev->ev_flags != EVLIST_INIT) return (-1); _event_debug_assert_is_setup(ev); ev->ev_base = base; ev->ev_pri = base->nactivequeues/2; return (0); } void event_set(struct event *ev, evutil_socket_t fd, short events, void (*callback)(evutil_socket_t, short, void *), void *arg) { int r; r = event_assign(ev, current_base, fd, events, callback, arg); EVUTIL_ASSERT(r == 0); } struct event * event_new(struct event_base *base, evutil_socket_t fd, short events, void (*cb)(evutil_socket_t, short, void *), void *arg) { struct event *ev; ev = mm_malloc(sizeof(struct event)); if (ev == NULL) return (NULL); if (event_assign(ev, base, fd, events, cb, arg) < 0) { mm_free(ev); return (NULL); } return (ev); } void event_free(struct event *ev) { _event_debug_assert_is_setup(ev); /* make sure that this event won't be coming back to haunt us. */ event_del(ev); _event_debug_note_teardown(ev); mm_free(ev); } void event_debug_unassign(struct event *ev) { _event_debug_assert_not_added(ev); _event_debug_note_teardown(ev); ev->ev_flags &= ~EVLIST_INIT; } /* * Set's the priority of an event - if an event is already scheduled * changing the priority is going to fail. */ int event_priority_set(struct event *ev, int pri) { _event_debug_assert_is_setup(ev); if (ev->ev_flags & EVLIST_ACTIVE) return (-1); if (pri < 0 || pri >= ev->ev_base->nactivequeues) return (-1); ev->ev_pri = pri; return (0); } /* * Checks if a specific event is pending or scheduled. */ int event_pending(const struct event *ev, short event, struct timeval *tv) { struct timeval now, res; int flags = 0; _event_debug_assert_is_setup(ev); if (ev->ev_flags & EVLIST_INSERTED) flags |= (ev->ev_events & (EV_READ|EV_WRITE|EV_SIGNAL)); if (ev->ev_flags & EVLIST_ACTIVE) flags |= ev->ev_res; if (ev->ev_flags & EVLIST_TIMEOUT) flags |= EV_TIMEOUT; event &= (EV_TIMEOUT|EV_READ|EV_WRITE|EV_SIGNAL); /* See if there is a timeout that we should report */ if (tv != NULL && (flags & event & EV_TIMEOUT)) { struct timeval tmp = ev->ev_timeout; event_base_gettimeofday_cached(ev->ev_base, &now); tmp.tv_usec &= MICROSECONDS_MASK; evutil_timersub(&tmp, &now, &res); /* correctly remap to real time */ evutil_gettimeofday(&now, NULL); evutil_timeradd(&now, &res, tv); } return (flags & event); } int _event_initialized(const struct event *ev, int need_fd) { if (!(ev->ev_flags & EVLIST_INIT)) return 0; #ifdef WIN32 /* XXX Is this actually a sensible thing to check? -NM */ if (need_fd && (ev)->ev_fd == (evutil_socket_t)INVALID_HANDLE_VALUE) return 0; #endif return 1; } void event_get_assignment(const struct event *event, struct event_base **base_out, evutil_socket_t *fd_out, short *events_out, event_callback_fn *callback_out, void **arg_out) { _event_debug_assert_is_setup(event); if (base_out) *base_out = event->ev_base; if (fd_out) *fd_out = event->ev_fd; if (events_out) *events_out = event->ev_events; if (callback_out) *callback_out = event->ev_callback; if (arg_out) *arg_out = event->ev_arg; } size_t event_get_struct_event_size(void) { return sizeof(struct event); } evutil_socket_t event_get_fd(const struct event *ev) { _event_debug_assert_is_setup(ev); return ev->ev_fd; } struct event_base * event_get_base(const struct event *ev) { _event_debug_assert_is_setup(ev); return ev->ev_base; } short event_get_events(const struct event *ev) { _event_debug_assert_is_setup(ev); return ev->ev_events; } event_callback_fn event_get_callback(const struct event *ev) { _event_debug_assert_is_setup(ev); return ev->ev_callback; } void * event_get_callback_arg(const struct event *ev) { _event_debug_assert_is_setup(ev); return ev->ev_arg; } int event_add(struct event *ev, const struct timeval *tv) { int res; EVBASE_ACQUIRE_LOCK(ev->ev_base, th_base_lock); res = event_add_internal(ev, tv, 0); EVBASE_RELEASE_LOCK(ev->ev_base, th_base_lock); return (res); } /* Helper callback: wake an event_base from another thread. This version * works by writing a byte to one end of a socketpair, so that the event_base * listening on the other end will wake up as the corresponding event * triggers */ static int evthread_notify_base_default(struct event_base *base) { char buf[1]; int r; buf[0] = (char) 0; #ifdef WIN32 r = send(base->th_notify_fd[1], buf, 1, 0); #else r = write(base->th_notify_fd[1], buf, 1); #endif return (r < 0) ? -1 : 0; } #if defined(_EVENT_HAVE_EVENTFD) && defined(_EVENT_HAVE_SYS_EVENTFD_H) /* Helper callback: wake an event_base from another thread. This version * assumes that you have a working eventfd() implementation. */ static int evthread_notify_base_eventfd(struct event_base *base) { ev_uint64_t msg = 1; int r; do { r = write(base->th_notify_fd[0], (void*) &msg, sizeof(msg)); } while (r < 0 && errno == EAGAIN); return (r < 0) ? -1 : 0; } #endif /** Tell the thread currently running the event_loop for base (if any) that it * needs to stop waiting in its dispatch function (if it is) and process all * active events and deferred callbacks (if there are any). */ static int evthread_notify_base(struct event_base *base) { if (!base->th_notify_fn) return -1; return base->th_notify_fn(base); } /* Implementation function to add an event. Works just like event_add, * except: 1) it requires that we have the lock. 2) if tv_is_absolute is set, * we treat tv as an absolute time, not as an interval to add to the current * time */ static inline int event_add_internal(struct event *ev, const struct timeval *tv, int tv_is_absolute) { struct event_base *base = ev->ev_base; int res = 0; int notify = 0; EVENT_BASE_ASSERT_LOCKED(base); _event_debug_assert_is_setup(ev); event_debug(( "event_add: event: %p, %s%s%scall %p", ev, ev->ev_events & EV_READ ? "EV_READ " : " ", ev->ev_events & EV_WRITE ? "EV_WRITE " : " ", tv ? "EV_TIMEOUT " : " ", ev->ev_callback)); EVUTIL_ASSERT(!(ev->ev_flags & ~EVLIST_ALL)); /* * prepare for timeout insertion further below, if we get a * failure on any step, we should not change any state. */ if (tv != NULL && !(ev->ev_flags & EVLIST_TIMEOUT)) { if (min_heap_reserve(&base->timeheap, 1 + min_heap_size(&base->timeheap)) == -1) return (-1); /* ENOMEM == errno */ } if ((ev->ev_events & (EV_READ|EV_WRITE|EV_SIGNAL)) && !(ev->ev_flags & (EVLIST_INSERTED|EVLIST_ACTIVE))) { if (ev->ev_events & (EV_READ|EV_WRITE)) res = evmap_io_add(base, ev->ev_fd, ev); else if (ev->ev_events & EV_SIGNAL) res = evmap_signal_add(base, ev->ev_fd, ev); if (res != -1) event_queue_insert(base, ev, EVLIST_INSERTED); if (res == 1) { /* evmap says we need to notify the main thread. */ notify = 1; res = 0; } } /* * we should change the timeout state only if the previous event * addition succeeded. */ if (res != -1 && tv != NULL) { struct timeval now; int common_timeout; /* * for persistent timeout events, we remember the * timeout value and re-add the event. * * If tv_is_absolute, this was already set. */ if (ev->ev_closure == EV_CLOSURE_PERSIST && !tv_is_absolute) ev->ev_io_timeout = *tv; /* * we already reserved memory above for the case where we * are not replacing an existing timeout. */ if (ev->ev_flags & EVLIST_TIMEOUT) { /* XXX I believe this is needless. */ if (min_heap_elt_is_top(ev)) notify = 1; event_queue_remove(base, ev, EVLIST_TIMEOUT); } /* Check if it is active due to a timeout. Rescheduling * this timeout before the callback can be executed * removes it from the active list. */ if ((ev->ev_flags & EVLIST_ACTIVE) && (ev->ev_res & EV_TIMEOUT)) { if (ev->ev_events & EV_SIGNAL) { /* See if we are just active executing * this event in a loop */ if (ev->ev_ncalls && ev->ev_pncalls) { /* Abort loop */ *ev->ev_pncalls = 0; } } event_queue_remove(base, ev, EVLIST_ACTIVE); } gettime(base, &now); common_timeout = is_common_timeout(tv, base); if (tv_is_absolute) { ev->ev_timeout = *tv; } else if (common_timeout) { struct timeval tmp = *tv; tmp.tv_usec &= MICROSECONDS_MASK; evutil_timeradd(&now, &tmp, &ev->ev_timeout); ev->ev_timeout.tv_usec |= (tv->tv_usec & ~MICROSECONDS_MASK); } else { evutil_timeradd(&now, tv, &ev->ev_timeout); } event_debug(( "event_add: timeout in %d seconds, call %p", (int)tv->tv_sec, ev->ev_callback)); event_queue_insert(base, ev, EVLIST_TIMEOUT); if (common_timeout) { struct common_timeout_list *ctl = get_common_timeout_list(base, &ev->ev_timeout); if (ev == TAILQ_FIRST(&ctl->events)) { common_timeout_schedule(ctl, &now, ev); } } else { /* See if the earliest timeout is now earlier than it * was before: if so, we will need to tell the main * thread to wake up earlier than it would * otherwise. */ if (min_heap_elt_is_top(ev)) notify = 1; } } /* if we are not in the right thread, we need to wake up the loop */ if (res != -1 && notify && !EVBASE_IN_THREAD(base)) evthread_notify_base(base); _event_debug_note_add(ev); return (res); } int event_del(struct event *ev) { int res; EVBASE_ACQUIRE_LOCK(ev->ev_base, th_base_lock); res = event_del_internal(ev); EVBASE_RELEASE_LOCK(ev->ev_base, th_base_lock); return (res); } /* Helper for event_del: always called with th_base_lock held. */ static inline int event_del_internal(struct event *ev) { struct event_base *base; int res = 0, notify = 0; int need_cur_lock; event_debug(("event_del: %p, callback %p", ev, ev->ev_callback)); /* An event without a base has not been added */ if (ev->ev_base == NULL) return (-1); EVENT_BASE_ASSERT_LOCKED(ev->ev_base); /* If the main thread is currently executing this event's callback, * and we are not the main thread, then we want to wait until the * callback is done before we start removing the event. That way, * when this function returns, it will be safe to free the * user-supplied argument. */ base = ev->ev_base; need_cur_lock = (base->current_event == ev); if (need_cur_lock) EVBASE_ACQUIRE_LOCK(base, current_event_lock); EVUTIL_ASSERT(!(ev->ev_flags & ~EVLIST_ALL)); /* See if we are just active executing this event in a loop */ if (ev->ev_events & EV_SIGNAL) { if (ev->ev_ncalls && ev->ev_pncalls) { /* Abort loop */ *ev->ev_pncalls = 0; } } if (ev->ev_flags & EVLIST_TIMEOUT) { /* NOTE: We never need to notify the main thread because of a * deleted timeout event: all that could happen if we don't is * that the dispatch loop might wake up too early. But the * point of notifying the main thread _is_ to wake up the * dispatch loop early anyway, so we wouldn't gain anything by * doing it. */ event_queue_remove(base, ev, EVLIST_TIMEOUT); } if (ev->ev_flags & EVLIST_ACTIVE) event_queue_remove(base, ev, EVLIST_ACTIVE); if (ev->ev_flags & EVLIST_INSERTED) { event_queue_remove(base, ev, EVLIST_INSERTED); if (ev->ev_events & (EV_READ|EV_WRITE)) res = evmap_io_del(base, ev->ev_fd, ev); else res = evmap_signal_del(base, ev->ev_fd, ev); if (res == 1) { /* evmap says we need to notify the main thread. */ notify = 1; res = 0; } } /* if we are not in the right thread, we need to wake up the loop */ if (res != -1 && notify && !EVBASE_IN_THREAD(base)) evthread_notify_base(base); if (need_cur_lock) EVBASE_RELEASE_LOCK(base, current_event_lock); _event_debug_note_del(ev); return (res); } void event_active(struct event *ev, int res, short ncalls) { EVBASE_ACQUIRE_LOCK(ev->ev_base, th_base_lock); _event_debug_assert_is_setup(ev); event_active_nolock(ev, res, ncalls); EVBASE_RELEASE_LOCK(ev->ev_base, th_base_lock); } void event_active_nolock(struct event *ev, int res, short ncalls) { struct event_base *base; /* We get different kinds of events, add them together */ if (ev->ev_flags & EVLIST_ACTIVE) { ev->ev_res |= res; return; } base = ev->ev_base; EVENT_BASE_ASSERT_LOCKED(base); ev->ev_res = res; if (ev->ev_events & EV_SIGNAL) { ev->ev_ncalls = ncalls; ev->ev_pncalls = NULL; } event_queue_insert(base, ev, EVLIST_ACTIVE); } void event_deferred_cb_init(struct deferred_cb *cb, deferred_cb_fn fn, void *arg) { memset(cb, 0, sizeof(struct deferred_cb)); cb->cb = fn; cb->arg = arg; } void event_deferred_cb_cancel(struct deferred_cb_queue *queue, struct deferred_cb *cb) { if (!queue) { if (current_base) queue = ¤t_base->defer_queue; else return; } LOCK_DEFERRED_QUEUE(queue); if (cb->queued) { TAILQ_REMOVE(&queue->deferred_cb_list, cb, cb_next); --queue->active_count; cb->queued = 0; } UNLOCK_DEFERRED_QUEUE(queue); } void event_deferred_cb_schedule(struct deferred_cb_queue *queue, struct deferred_cb *cb) { if (!queue) { if (current_base) queue = ¤t_base->defer_queue; else return; } LOCK_DEFERRED_QUEUE(queue); if (!cb->queued) { cb->queued = 1; TAILQ_INSERT_TAIL(&queue->deferred_cb_list, cb, cb_next); ++queue->active_count; /* XXXX Can we get away with doing this only when adding * the first active deferred_cb to the queue? */ if (queue->notify_fn) queue->notify_fn(queue, queue->notify_arg); } UNLOCK_DEFERRED_QUEUE(queue); } static int timeout_next(struct event_base *base, struct timeval **tv_p) { /* Caller must hold th_base_lock */ struct timeval now; struct event *ev; struct timeval *tv = *tv_p; int res = 0; ev = min_heap_top(&base->timeheap); if (ev == NULL) { /* if no time-based events are active wait for I/O */ *tv_p = NULL; goto out; } if (gettime(base, &now) == -1) { res = -1; goto out; } if (evutil_timercmp(&ev->ev_timeout, &now, <=)) { evutil_timerclear(tv); goto out; } evutil_timersub(&ev->ev_timeout, &now, tv); EVUTIL_ASSERT(tv->tv_sec >= 0); EVUTIL_ASSERT(tv->tv_usec >= 0); event_debug(("timeout_next: in %d seconds", (int)tv->tv_sec)); out: return (res); } /* * Determines if the time is running backwards by comparing the current time * against the last time we checked. Not needed when using clock monotonic. * If time is running backwards, we adjust the firing time of every event by * the amount that time seems to have jumped. */ static void timeout_correct(struct event_base *base, struct timeval *tv) { /* Caller must hold th_base_lock. */ struct event **pev; unsigned int size; struct timeval off; int i; if (use_monotonic) return; /* Check if time is running backwards */ gettime(base, tv); if (evutil_timercmp(tv, &base->event_tv, >=)) { base->event_tv = *tv; return; } event_debug(("%s: time is running backwards, corrected", __func__)); evutil_timersub(&base->event_tv, tv, &off); /* * We can modify the key element of the node without destroying * the minheap property, because we change every element. */ pev = base->timeheap.p; size = base->timeheap.n; for (; size-- > 0; ++pev) { struct timeval *ev_tv = &(**pev).ev_timeout; evutil_timersub(ev_tv, &off, ev_tv); } for (i=0; i<base->n_common_timeouts; ++i) { struct event *ev; struct common_timeout_list *ctl = base->common_timeout_queues[i]; TAILQ_FOREACH(ev, &ctl->events, ev_timeout_pos.ev_next_with_common_timeout) { struct timeval *ev_tv = &ev->ev_timeout; ev_tv->tv_usec &= MICROSECONDS_MASK; evutil_timersub(ev_tv, &off, ev_tv); ev_tv->tv_usec |= COMMON_TIMEOUT_MAGIC | (i<<COMMON_TIMEOUT_IDX_SHIFT); } } /* Now remember what the new time turned out to be. */ base->event_tv = *tv; } /* Activate every event whose timeout has elapsed. */ static void timeout_process(struct event_base *base) { /* Caller must hold lock. */ struct timeval now; struct event *ev; if (min_heap_empty(&base->timeheap)) { return; } gettime(base, &now); while ((ev = min_heap_top(&base->timeheap))) { if (evutil_timercmp(&ev->ev_timeout, &now, >)) break; /* delete this event from the I/O queues */ event_del_internal(ev); event_debug(("timeout_process: call %p", ev->ev_callback)); event_active_nolock(ev, EV_TIMEOUT, 1); } } /* Remove 'ev' from 'queue' (EVLIST_...) in base. */ static void event_queue_remove(struct event_base *base, struct event *ev, int queue) { EVENT_BASE_ASSERT_LOCKED(base); if (!(ev->ev_flags & queue)) { event_errx(1, "%s: %p(fd %d) not on queue %x", __func__, ev, ev->ev_fd, queue); return; } if (~ev->ev_flags & EVLIST_INTERNAL) base->event_count--; ev->ev_flags &= ~queue; switch (queue) { case EVLIST_INSERTED: TAILQ_REMOVE(&base->eventqueue, ev, ev_next); break; case EVLIST_ACTIVE: base->event_count_active--; TAILQ_REMOVE(&base->activequeues[ev->ev_pri], ev, ev_active_next); break; case EVLIST_TIMEOUT: if (is_common_timeout(&ev->ev_timeout, base)) { struct common_timeout_list *ctl = get_common_timeout_list(base, &ev->ev_timeout); TAILQ_REMOVE(&ctl->events, ev, ev_timeout_pos.ev_next_with_common_timeout); } else { min_heap_erase(&base->timeheap, ev); } break; default: event_errx(1, "%s: unknown queue %x", __func__, queue); } } /* Add 'ev' to the common timeout list in 'ev'. */ static void insert_common_timeout_inorder(struct common_timeout_list *ctl, struct event *ev) { struct event *e; /* By all logic, we should just be able to append 'ev' to the end of * ctl->events, since the timeout on each 'ev' is set to {the common * timeout} + {the time when we add the event}, and so the events * should arrive in order of their timeeouts. But just in case * there's some wacky threading issue going on, we do a search from * the end of 'ev' to find the right insertion point. */ TAILQ_FOREACH_REVERSE(e, &ctl->events, ev_timeout_pos.ev_next_with_common_timeout, event_list) { /* This timercmp is a little sneaky, since both ev and e have * magic values in tv_usec. Fortunately, they ought to have * the _same_ magic values in tv_usec. Let's assert for that. */ EVUTIL_ASSERT( is_same_common_timeout(&e->ev_timeout, &ev->ev_timeout)); if (evutil_timercmp(&ev->ev_timeout, &e->ev_timeout, >=)) { TAILQ_INSERT_AFTER(&ctl->events, e, ev, ev_timeout_pos.ev_next_with_common_timeout); return; } } TAILQ_INSERT_HEAD(&ctl->events, ev, ev_timeout_pos.ev_next_with_common_timeout); } static void event_queue_insert(struct event_base *base, struct event *ev, int queue) { EVENT_BASE_ASSERT_LOCKED(base); if (ev->ev_flags & queue) { /* Double insertion is possible for active events */ if (queue & EVLIST_ACTIVE) return; event_errx(1, "%s: %p(fd %d) already on queue %x", __func__, ev, ev->ev_fd, queue); return; } if (~ev->ev_flags & EVLIST_INTERNAL) base->event_count++; ev->ev_flags |= queue; switch (queue) { case EVLIST_INSERTED: TAILQ_INSERT_TAIL(&base->eventqueue, ev, ev_next); break; case EVLIST_ACTIVE: base->event_count_active++; TAILQ_INSERT_TAIL(&base->activequeues[ev->ev_pri], ev,ev_active_next); break; case EVLIST_TIMEOUT: { if (is_common_timeout(&ev->ev_timeout, base)) { struct common_timeout_list *ctl = get_common_timeout_list(base, &ev->ev_timeout); insert_common_timeout_inorder(ctl, ev); } else min_heap_push(&base->timeheap, ev); break; } default: event_errx(1, "%s: unknown queue %x", __func__, queue); } } /* Functions for debugging */ const char * event_get_version(void) { return (_EVENT_VERSION); } ev_uint32_t event_get_version_number(void) { return (_EVENT_NUMERIC_VERSION); } /* * No thread-safe interface needed - the information should be the same * for all threads. */ const char * event_get_method(void) { return (current_base->evsel->name); } #ifndef _EVENT_DISABLE_MM_REPLACEMENT static void *(*_mm_malloc_fn)(size_t sz) = NULL; static void *(*_mm_realloc_fn)(void *p, size_t sz) = NULL; static void (*_mm_free_fn)(void *p) = NULL; void * mm_malloc(size_t sz) { if (_mm_malloc_fn) return _mm_malloc_fn(sz); else return malloc(sz); } void * mm_calloc(size_t count, size_t size) { if (_mm_malloc_fn) { size_t sz = count * size; void *p = _mm_malloc_fn(sz); if (p) memset(p, 0, sz); return p; } else return calloc(count, size); } char * mm_strdup(const char *str) { if (_mm_malloc_fn) { size_t ln = strlen(str); void *p = _mm_malloc_fn(ln+1); if (p) memcpy(p, str, ln+1); return p; } else #ifdef WIN32 return _strdup(str); #else return strdup(str); #endif } void * mm_realloc(void *ptr, size_t sz) { if (_mm_realloc_fn) return _mm_realloc_fn(ptr, sz); else return realloc(ptr, sz); } void mm_free(void *ptr) { if (_mm_free_fn) _mm_free_fn(ptr); else free(ptr); } void event_set_mem_functions(void *(*malloc_fn)(size_t sz), void *(*realloc_fn)(void *ptr, size_t sz), void (*free_fn)(void *ptr)) { _mm_malloc_fn = malloc_fn; _mm_realloc_fn = realloc_fn; _mm_free_fn = free_fn; } #endif #if defined(_EVENT_HAVE_EVENTFD) && defined(_EVENT_HAVE_SYS_EVENTFD_H) static void evthread_notify_drain_eventfd(evutil_socket_t fd, short what, void *arg) { ev_uint64_t msg; ev_ssize_t r; r = read(fd, (void*) &msg, sizeof(msg)); if (r<0 && errno != EAGAIN) { event_sock_warn(fd, "Error reading from eventfd"); } } #endif static void evthread_notify_drain_default(evutil_socket_t fd, short what, void *arg) { unsigned char buf[128]; #ifdef WIN32 while (recv(fd, (char*)buf, sizeof(buf), 0) > 0) ; #else while (read(fd, (char*)buf, sizeof(buf)) > 0) ; #endif } int evthread_make_base_notifiable(struct event_base *base) { void (*cb)(evutil_socket_t, short, void *) = evthread_notify_drain_default; int (*notify)(struct event_base *) = evthread_notify_base_default; /* XXXX grab the lock here? */ if (!base) return -1; if (base->th_notify_fd[0] >= 0) return 0; #if defined(_EVENT_HAVE_EVENTFD) && defined(_EVENT_HAVE_SYS_EVENTFD_H) base->th_notify_fd[0] = eventfd(0, 0); if (base->th_notify_fd[0] >= 0) { notify = evthread_notify_base_eventfd; cb = evthread_notify_drain_eventfd; } else #endif #if defined(_EVENT_HAVE_PIPE) { if ((base->evsel->features & EV_FEATURE_FDS)) { if (pipe(base->th_notify_fd) < 0) event_warn("%s: pipe", __func__); } } if (base->th_notify_fd[0] < 0) #endif #ifdef WIN32 #define LOCAL_SOCKETPAIR_AF AF_INET #else #define LOCAL_SOCKETPAIR_AF AF_UNIX #endif { if (evutil_socketpair(LOCAL_SOCKETPAIR_AF, SOCK_STREAM, 0, base->th_notify_fd) == -1) { event_sock_warn(-1, "%s: socketpair", __func__); return (-1); } } evutil_make_socket_nonblocking(base->th_notify_fd[0]); base->th_notify_fn = notify; /* This can't be right, can it? We want writes to this socket to just succeed. evutil_make_socket_nonblocking(base->th_notify_fd[1]); */ /* prepare an event that we can use for wakeup */ event_assign(&base->th_notify, base, base->th_notify_fd[0], EV_READ|EV_PERSIST, cb, base); /* we need to mark this as internal event */ base->th_notify.ev_flags |= EVLIST_INTERNAL; return event_add(&base->th_notify, NULL); } void event_base_dump_events(struct event_base *base, FILE *output) { struct event *e; int i; fprintf(output, "Inserted events:\n"); TAILQ_FOREACH(e, &base->eventqueue, ev_next) { fprintf(output, " %p [fd %ld]%s%s%s%s%s\n", (void*)e, (long)e->ev_fd, (e->ev_events&EV_READ)?" Read":"", (e->ev_events&EV_WRITE)?" Write":"", (e->ev_events&EV_SIGNAL)?" Signal":"", (e->ev_events&EV_TIMEOUT)?" Timeout":"", (e->ev_events&EV_PERSIST)?" Persist":""); } for (i = 0; i < base->nactivequeues; ++i) { if (TAILQ_EMPTY(&base->activequeues[i])) continue; fprintf(output, "Active events [priority %d]:\n", i); TAILQ_FOREACH(e, &base->eventqueue, ev_next) { fprintf(output, " %p [fd %ld]%s%s%s%s\n", (void*)e, (long)e->ev_fd, (e->ev_res&EV_READ)?" Read active":"", (e->ev_res&EV_WRITE)?" Write active":"", (e->ev_res&EV_SIGNAL)?" Signal active":"", (e->ev_res&EV_TIMEOUT)?" Timeout active":""); } } }