diff options
author | Tom Gundersen <teg@jklm.no> | 2014-01-21 14:10:18 +0100 |
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committer | Tom Gundersen <teg@jklm.no> | 2014-01-21 14:41:35 +0100 |
commit | 607553f9306286fdccf0b356bc3d1087adfe21c4 (patch) | |
tree | eedb987304b96ecaf22348c372a93d6ac5fbf594 /src/libsystemd/sd-event.c | |
parent | 43d9c2b5848b1363b659c38443c1c94db57415fd (diff) |
libsystemd: split up into subdirs
We still only produce on .so, but let's keep the sources separate to make things a bit
less messy.
Diffstat (limited to 'src/libsystemd/sd-event.c')
-rw-r--r-- | src/libsystemd/sd-event.c | 2224 |
1 files changed, 0 insertions, 2224 deletions
diff --git a/src/libsystemd/sd-event.c b/src/libsystemd/sd-event.c deleted file mode 100644 index f33a9ecf9a..0000000000 --- a/src/libsystemd/sd-event.c +++ /dev/null @@ -1,2224 +0,0 @@ -/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ - -/*** - This file is part of systemd. - - Copyright 2013 Lennart Poettering - - systemd is free software; you can redistribute it and/or modify it - under the terms of the GNU Lesser General Public License as published by - the Free Software Foundation; either version 2.1 of the License, or - (at your option) any later version. - - systemd is distributed in the hope that it will be useful, but - WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public License - along with systemd; If not, see <http://www.gnu.org/licenses/>. -***/ - -#include <sys/epoll.h> -#include <sys/timerfd.h> -#include <sys/wait.h> -#include <pthread.h> - -#include "sd-id128.h" -#include "sd-daemon.h" -#include "macro.h" -#include "prioq.h" -#include "hashmap.h" -#include "util.h" -#include "time-util.h" -#include "missing.h" - -#include "sd-event.h" - -#define EPOLL_QUEUE_MAX 512U -#define DEFAULT_ACCURACY_USEC (250 * USEC_PER_MSEC) - -typedef enum EventSourceType { - SOURCE_IO, - SOURCE_MONOTONIC, - SOURCE_REALTIME, - SOURCE_SIGNAL, - SOURCE_CHILD, - SOURCE_DEFER, - SOURCE_EXIT, - SOURCE_WATCHDOG -} EventSourceType; - -struct sd_event_source { - unsigned n_ref; - - sd_event *event; - void *userdata; - sd_event_handler_t prepare; - - EventSourceType type:4; - int enabled:3; - bool pending:1; - bool dispatching:1; - - int64_t priority; - unsigned pending_index; - unsigned prepare_index; - unsigned pending_iteration; - unsigned prepare_iteration; - - union { - struct { - sd_event_io_handler_t callback; - int fd; - uint32_t events; - uint32_t revents; - bool registered:1; - } io; - struct { - sd_event_time_handler_t callback; - usec_t next, accuracy; - unsigned earliest_index; - unsigned latest_index; - } time; - struct { - sd_event_signal_handler_t callback; - struct signalfd_siginfo siginfo; - int sig; - } signal; - struct { - sd_event_child_handler_t callback; - siginfo_t siginfo; - pid_t pid; - int options; - } child; - struct { - sd_event_handler_t callback; - } defer; - struct { - sd_event_handler_t callback; - unsigned prioq_index; - } exit; - }; -}; - -struct sd_event { - unsigned n_ref; - - int epoll_fd; - int signal_fd; - int realtime_fd; - int monotonic_fd; - int watchdog_fd; - - Prioq *pending; - Prioq *prepare; - - /* For both clocks we maintain two priority queues each, one - * ordered for the earliest times the events may be - * dispatched, and one ordered by the latest times they must - * have been dispatched. The range between the top entries in - * the two prioqs is the time window we can freely schedule - * wakeups in */ - Prioq *monotonic_earliest; - Prioq *monotonic_latest; - Prioq *realtime_earliest; - Prioq *realtime_latest; - - usec_t realtime_next, monotonic_next; - usec_t perturb; - - sigset_t sigset; - sd_event_source **signal_sources; - - Hashmap *child_sources; - unsigned n_enabled_child_sources; - - Prioq *exit; - - pid_t original_pid; - - unsigned iteration; - dual_timestamp timestamp; - int state; - - bool exit_requested:1; - bool need_process_child:1; - bool watchdog:1; - - int exit_code; - - pid_t tid; - sd_event **default_event_ptr; - - usec_t watchdog_last, watchdog_period; - - unsigned n_sources; -}; - -static int pending_prioq_compare(const void *a, const void *b) { - const sd_event_source *x = a, *y = b; - - assert(x->pending); - assert(y->pending); - - /* Enabled ones first */ - if (x->enabled != SD_EVENT_OFF && y->enabled == SD_EVENT_OFF) - return -1; - if (x->enabled == SD_EVENT_OFF && y->enabled != SD_EVENT_OFF) - return 1; - - /* Lower priority values first */ - if (x->priority < y->priority) - return -1; - if (x->priority > y->priority) - return 1; - - /* Older entries first */ - if (x->pending_iteration < y->pending_iteration) - return -1; - if (x->pending_iteration > y->pending_iteration) - return 1; - - /* Stability for the rest */ - if (x < y) - return -1; - if (x > y) - return 1; - - return 0; -} - -static int prepare_prioq_compare(const void *a, const void *b) { - const sd_event_source *x = a, *y = b; - - assert(x->prepare); - assert(y->prepare); - - /* Move most recently prepared ones last, so that we can stop - * preparing as soon as we hit one that has already been - * prepared in the current iteration */ - if (x->prepare_iteration < y->prepare_iteration) - return -1; - if (x->prepare_iteration > y->prepare_iteration) - return 1; - - /* Enabled ones first */ - if (x->enabled != SD_EVENT_OFF && y->enabled == SD_EVENT_OFF) - return -1; - if (x->enabled == SD_EVENT_OFF && y->enabled != SD_EVENT_OFF) - return 1; - - /* Lower priority values first */ - if (x->priority < y->priority) - return -1; - if (x->priority > y->priority) - return 1; - - /* Stability for the rest */ - if (x < y) - return -1; - if (x > y) - return 1; - - return 0; -} - -static int earliest_time_prioq_compare(const void *a, const void *b) { - const sd_event_source *x = a, *y = b; - - assert(x->type == SOURCE_MONOTONIC || x->type == SOURCE_REALTIME); - assert(y->type == SOURCE_MONOTONIC || y->type == SOURCE_REALTIME); - - /* Enabled ones first */ - if (x->enabled != SD_EVENT_OFF && y->enabled == SD_EVENT_OFF) - return -1; - if (x->enabled == SD_EVENT_OFF && y->enabled != SD_EVENT_OFF) - return 1; - - /* Move the pending ones to the end */ - if (!x->pending && y->pending) - return -1; - if (x->pending && !y->pending) - return 1; - - /* Order by time */ - if (x->time.next < y->time.next) - return -1; - if (x->time.next > y->time.next) - return 1; - - /* Stability for the rest */ - if (x < y) - return -1; - if (x > y) - return 1; - - return 0; -} - -static int latest_time_prioq_compare(const void *a, const void *b) { - const sd_event_source *x = a, *y = b; - - assert((x->type == SOURCE_MONOTONIC && y->type == SOURCE_MONOTONIC) || - (x->type == SOURCE_REALTIME && y->type == SOURCE_REALTIME)); - - /* Enabled ones first */ - if (x->enabled != SD_EVENT_OFF && y->enabled == SD_EVENT_OFF) - return -1; - if (x->enabled == SD_EVENT_OFF && y->enabled != SD_EVENT_OFF) - return 1; - - /* Move the pending ones to the end */ - if (!x->pending && y->pending) - return -1; - if (x->pending && !y->pending) - return 1; - - /* Order by time */ - if (x->time.next + x->time.accuracy < y->time.next + y->time.accuracy) - return -1; - if (x->time.next + x->time.accuracy > y->time.next + y->time.accuracy) - return 1; - - /* Stability for the rest */ - if (x < y) - return -1; - if (x > y) - return 1; - - return 0; -} - -static int exit_prioq_compare(const void *a, const void *b) { - const sd_event_source *x = a, *y = b; - - assert(x->type == SOURCE_EXIT); - assert(y->type == SOURCE_EXIT); - - /* Enabled ones first */ - if (x->enabled != SD_EVENT_OFF && y->enabled == SD_EVENT_OFF) - return -1; - if (x->enabled == SD_EVENT_OFF && y->enabled != SD_EVENT_OFF) - return 1; - - /* Lower priority values first */ - if (x->priority < y->priority) - return -1; - if (x->priority > y->priority) - return 1; - - /* Stability for the rest */ - if (x < y) - return -1; - if (x > y) - return 1; - - return 0; -} - -static void event_free(sd_event *e) { - assert(e); - assert(e->n_sources == 0); - - if (e->default_event_ptr) - *(e->default_event_ptr) = NULL; - - if (e->epoll_fd >= 0) - close_nointr_nofail(e->epoll_fd); - - if (e->signal_fd >= 0) - close_nointr_nofail(e->signal_fd); - - if (e->realtime_fd >= 0) - close_nointr_nofail(e->realtime_fd); - - if (e->monotonic_fd >= 0) - close_nointr_nofail(e->monotonic_fd); - - if (e->watchdog_fd >= 0) - close_nointr_nofail(e->watchdog_fd); - - prioq_free(e->pending); - prioq_free(e->prepare); - prioq_free(e->monotonic_earliest); - prioq_free(e->monotonic_latest); - prioq_free(e->realtime_earliest); - prioq_free(e->realtime_latest); - prioq_free(e->exit); - - free(e->signal_sources); - - hashmap_free(e->child_sources); - free(e); -} - -_public_ int sd_event_new(sd_event** ret) { - sd_event *e; - int r; - - assert_return(ret, -EINVAL); - - e = new0(sd_event, 1); - if (!e) - return -ENOMEM; - - e->n_ref = 1; - e->signal_fd = e->realtime_fd = e->monotonic_fd = e->watchdog_fd = e->epoll_fd = -1; - e->realtime_next = e->monotonic_next = (usec_t) -1; - e->original_pid = getpid(); - - assert_se(sigemptyset(&e->sigset) == 0); - - e->pending = prioq_new(pending_prioq_compare); - if (!e->pending) { - r = -ENOMEM; - goto fail; - } - - e->epoll_fd = epoll_create1(EPOLL_CLOEXEC); - if (e->epoll_fd < 0) { - r = -errno; - goto fail; - } - - *ret = e; - return 0; - -fail: - event_free(e); - return r; -} - -_public_ sd_event* sd_event_ref(sd_event *e) { - assert_return(e, NULL); - - assert(e->n_ref >= 1); - e->n_ref++; - - return e; -} - -_public_ sd_event* sd_event_unref(sd_event *e) { - - if (!e) - return NULL; - - assert(e->n_ref >= 1); - e->n_ref--; - - if (e->n_ref <= 0) - event_free(e); - - return NULL; -} - -static bool event_pid_changed(sd_event *e) { - assert(e); - - /* We don't support people creating am event loop and keeping - * it around over a fork(). Let's complain. */ - - return e->original_pid != getpid(); -} - -static int source_io_unregister(sd_event_source *s) { - int r; - - assert(s); - assert(s->type == SOURCE_IO); - - if (!s->io.registered) - return 0; - - r = epoll_ctl(s->event->epoll_fd, EPOLL_CTL_DEL, s->io.fd, NULL); - if (r < 0) - return -errno; - - s->io.registered = false; - return 0; -} - -static int source_io_register( - sd_event_source *s, - int enabled, - uint32_t events) { - - struct epoll_event ev = {}; - int r; - - assert(s); - assert(s->type == SOURCE_IO); - assert(enabled != SD_EVENT_OFF); - - ev.events = events; - ev.data.ptr = s; - - if (enabled == SD_EVENT_ONESHOT) - ev.events |= EPOLLONESHOT; - - if (s->io.registered) - r = epoll_ctl(s->event->epoll_fd, EPOLL_CTL_MOD, s->io.fd, &ev); - else - r = epoll_ctl(s->event->epoll_fd, EPOLL_CTL_ADD, s->io.fd, &ev); - - if (r < 0) - return -errno; - - s->io.registered = true; - - return 0; -} - -static void source_free(sd_event_source *s) { - assert(s); - - if (s->event) { - assert(s->event->n_sources > 0); - - switch (s->type) { - - case SOURCE_IO: - if (s->io.fd >= 0) - source_io_unregister(s); - - break; - - case SOURCE_MONOTONIC: - prioq_remove(s->event->monotonic_earliest, s, &s->time.earliest_index); - prioq_remove(s->event->monotonic_latest, s, &s->time.latest_index); - break; - - case SOURCE_REALTIME: - prioq_remove(s->event->realtime_earliest, s, &s->time.earliest_index); - prioq_remove(s->event->realtime_latest, s, &s->time.latest_index); - break; - - case SOURCE_SIGNAL: - if (s->signal.sig > 0) { - if (s->signal.sig != SIGCHLD || s->event->n_enabled_child_sources == 0) - assert_se(sigdelset(&s->event->sigset, s->signal.sig) == 0); - - if (s->event->signal_sources) - s->event->signal_sources[s->signal.sig] = NULL; - } - - break; - - case SOURCE_CHILD: - if (s->child.pid > 0) { - if (s->enabled != SD_EVENT_OFF) { - assert(s->event->n_enabled_child_sources > 0); - s->event->n_enabled_child_sources--; - } - - if (!s->event->signal_sources || !s->event->signal_sources[SIGCHLD]) - assert_se(sigdelset(&s->event->sigset, SIGCHLD) == 0); - - hashmap_remove(s->event->child_sources, INT_TO_PTR(s->child.pid)); - } - - break; - - case SOURCE_DEFER: - /* nothing */ - break; - - case SOURCE_EXIT: - prioq_remove(s->event->exit, s, &s->exit.prioq_index); - break; - - case SOURCE_WATCHDOG: - assert_not_reached("Wut? I shouldn't exist."); - } - - if (s->pending) - prioq_remove(s->event->pending, s, &s->pending_index); - - if (s->prepare) - prioq_remove(s->event->prepare, s, &s->prepare_index); - - s->event->n_sources--; - sd_event_unref(s->event); - } - - free(s); -} - -static int source_set_pending(sd_event_source *s, bool b) { - int r; - - assert(s); - assert(s->type != SOURCE_EXIT); - - if (s->pending == b) - return 0; - - s->pending = b; - - if (b) { - s->pending_iteration = s->event->iteration; - - r = prioq_put(s->event->pending, s, &s->pending_index); - if (r < 0) { - s->pending = false; - return r; - } - } else - assert_se(prioq_remove(s->event->pending, s, &s->pending_index)); - - if (s->type == SOURCE_REALTIME) { - prioq_reshuffle(s->event->realtime_earliest, s, &s->time.earliest_index); - prioq_reshuffle(s->event->realtime_latest, s, &s->time.latest_index); - } else if (s->type == SOURCE_MONOTONIC) { - prioq_reshuffle(s->event->monotonic_earliest, s, &s->time.earliest_index); - prioq_reshuffle(s->event->monotonic_latest, s, &s->time.latest_index); - } - - return 0; -} - -static sd_event_source *source_new(sd_event *e, EventSourceType type) { - sd_event_source *s; - - assert(e); - - s = new0(sd_event_source, 1); - if (!s) - return NULL; - - s->n_ref = 1; - s->event = sd_event_ref(e); - s->type = type; - s->pending_index = s->prepare_index = PRIOQ_IDX_NULL; - - e->n_sources ++; - - return s; -} - -_public_ int sd_event_add_io( - sd_event *e, - int fd, - uint32_t events, - sd_event_io_handler_t callback, - void *userdata, - sd_event_source **ret) { - - sd_event_source *s; - int r; - - assert_return(e, -EINVAL); - assert_return(fd >= 0, -EINVAL); - assert_return(!(events & ~(EPOLLIN|EPOLLOUT|EPOLLRDHUP|EPOLLPRI|EPOLLERR|EPOLLHUP|EPOLLET)), -EINVAL); - assert_return(callback, -EINVAL); - assert_return(ret, -EINVAL); - assert_return(e->state != SD_EVENT_FINISHED, -ESTALE); - assert_return(!event_pid_changed(e), -ECHILD); - - s = source_new(e, SOURCE_IO); - if (!s) - return -ENOMEM; - - s->io.fd = fd; - s->io.events = events; - s->io.callback = callback; - s->userdata = userdata; - s->enabled = SD_EVENT_ON; - - r = source_io_register(s, s->enabled, events); - if (r < 0) { - source_free(s); - return -errno; - } - - *ret = s; - return 0; -} - -static int event_setup_timer_fd( - sd_event *e, - EventSourceType type, - int *timer_fd, - clockid_t id) { - - struct epoll_event ev = {}; - int r, fd; - sd_id128_t bootid; - - assert(e); - assert(timer_fd); - - if (_likely_(*timer_fd >= 0)) - return 0; - - fd = timerfd_create(id, TFD_NONBLOCK|TFD_CLOEXEC); - if (fd < 0) - return -errno; - - ev.events = EPOLLIN; - ev.data.ptr = INT_TO_PTR(type); - - r = epoll_ctl(e->epoll_fd, EPOLL_CTL_ADD, fd, &ev); - if (r < 0) { - close_nointr_nofail(fd); - return -errno; - } - - /* When we sleep for longer, we try to realign the wakeup to - the same time wihtin each minute/second/250ms, so that - events all across the system can be coalesced into a single - CPU wakeup. However, let's take some system-specific - randomness for this value, so that in a network of systems - with synced clocks timer events are distributed a - bit. Here, we calculate a perturbation usec offset from the - boot ID. */ - - if (sd_id128_get_boot(&bootid) >= 0) - e->perturb = (bootid.qwords[0] ^ bootid.qwords[1]) % USEC_PER_MINUTE; - - *timer_fd = fd; - return 0; -} - -static int event_add_time_internal( - sd_event *e, - EventSourceType type, - int *timer_fd, - clockid_t id, - Prioq **earliest, - Prioq **latest, - uint64_t usec, - uint64_t accuracy, - sd_event_time_handler_t callback, - void *userdata, - sd_event_source **ret) { - - sd_event_source *s; - int r; - - assert_return(e, -EINVAL); - assert_return(callback, -EINVAL); - assert_return(ret, -EINVAL); - assert_return(usec != (uint64_t) -1, -EINVAL); - assert_return(accuracy != (uint64_t) -1, -EINVAL); - assert_return(e->state != SD_EVENT_FINISHED, -ESTALE); - assert_return(!event_pid_changed(e), -ECHILD); - - assert(timer_fd); - assert(earliest); - assert(latest); - - if (!*earliest) { - *earliest = prioq_new(earliest_time_prioq_compare); - if (!*earliest) - return -ENOMEM; - } - - if (!*latest) { - *latest = prioq_new(latest_time_prioq_compare); - if (!*latest) - return -ENOMEM; - } - - if (*timer_fd < 0) { - r = event_setup_timer_fd(e, type, timer_fd, id); - if (r < 0) - return r; - } - - s = source_new(e, type); - if (!s) - return -ENOMEM; - - s->time.next = usec; - s->time.accuracy = accuracy == 0 ? DEFAULT_ACCURACY_USEC : accuracy; - s->time.callback = callback; - s->time.earliest_index = s->time.latest_index = PRIOQ_IDX_NULL; - s->userdata = userdata; - s->enabled = SD_EVENT_ONESHOT; - - r = prioq_put(*earliest, s, &s->time.earliest_index); - if (r < 0) - goto fail; - - r = prioq_put(*latest, s, &s->time.latest_index); - if (r < 0) - goto fail; - - *ret = s; - return 0; - -fail: - source_free(s); - return r; -} - -_public_ int sd_event_add_monotonic(sd_event *e, - uint64_t usec, - uint64_t accuracy, - sd_event_time_handler_t callback, - void *userdata, - sd_event_source **ret) { - - return event_add_time_internal(e, SOURCE_MONOTONIC, &e->monotonic_fd, CLOCK_MONOTONIC, &e->monotonic_earliest, &e->monotonic_latest, usec, accuracy, callback, userdata, ret); -} - -_public_ int sd_event_add_realtime(sd_event *e, - uint64_t usec, - uint64_t accuracy, - sd_event_time_handler_t callback, - void *userdata, - sd_event_source **ret) { - - return event_add_time_internal(e, SOURCE_REALTIME, &e->realtime_fd, CLOCK_REALTIME, &e->realtime_earliest, &e->monotonic_latest, usec, accuracy, callback, userdata, ret); -} - -static int event_update_signal_fd(sd_event *e) { - struct epoll_event ev = {}; - bool add_to_epoll; - int r; - - assert(e); - - add_to_epoll = e->signal_fd < 0; - - r = signalfd(e->signal_fd, &e->sigset, SFD_NONBLOCK|SFD_CLOEXEC); - if (r < 0) - return -errno; - - e->signal_fd = r; - - if (!add_to_epoll) - return 0; - - ev.events = EPOLLIN; - ev.data.ptr = INT_TO_PTR(SOURCE_SIGNAL); - - r = epoll_ctl(e->epoll_fd, EPOLL_CTL_ADD, e->signal_fd, &ev); - if (r < 0) { - close_nointr_nofail(e->signal_fd); - e->signal_fd = -1; - - return -errno; - } - - return 0; -} - -_public_ int sd_event_add_signal( - sd_event *e, - int sig, - sd_event_signal_handler_t callback, - void *userdata, - sd_event_source **ret) { - - sd_event_source *s; - sigset_t ss; - int r; - - assert_return(e, -EINVAL); - assert_return(sig > 0, -EINVAL); - assert_return(sig < _NSIG, -EINVAL); - assert_return(callback, -EINVAL); - assert_return(ret, -EINVAL); - assert_return(e->state != SD_EVENT_FINISHED, -ESTALE); - assert_return(!event_pid_changed(e), -ECHILD); - - r = pthread_sigmask(SIG_SETMASK, NULL, &ss); - if (r < 0) - return -errno; - - if (!sigismember(&ss, sig)) - return -EBUSY; - - if (!e->signal_sources) { - e->signal_sources = new0(sd_event_source*, _NSIG); - if (!e->signal_sources) - return -ENOMEM; - } else if (e->signal_sources[sig]) - return -EBUSY; - - s = source_new(e, SOURCE_SIGNAL); - if (!s) - return -ENOMEM; - - s->signal.sig = sig; - s->signal.callback = callback; - s->userdata = userdata; - s->enabled = SD_EVENT_ON; - - e->signal_sources[sig] = s; - assert_se(sigaddset(&e->sigset, sig) == 0); - - if (sig != SIGCHLD || e->n_enabled_child_sources == 0) { - r = event_update_signal_fd(e); - if (r < 0) { - source_free(s); - return r; - } - } - - *ret = s; - return 0; -} - -_public_ int sd_event_add_child( - sd_event *e, - pid_t pid, - int options, - sd_event_child_handler_t callback, - void *userdata, - sd_event_source **ret) { - - sd_event_source *s; - int r; - - assert_return(e, -EINVAL); - assert_return(pid > 1, -EINVAL); - assert_return(!(options & ~(WEXITED|WSTOPPED|WCONTINUED)), -EINVAL); - assert_return(options != 0, -EINVAL); - assert_return(callback, -EINVAL); - assert_return(ret, -EINVAL); - assert_return(e->state != SD_EVENT_FINISHED, -ESTALE); - assert_return(!event_pid_changed(e), -ECHILD); - - r = hashmap_ensure_allocated(&e->child_sources, trivial_hash_func, trivial_compare_func); - if (r < 0) - return r; - - if (hashmap_contains(e->child_sources, INT_TO_PTR(pid))) - return -EBUSY; - - s = source_new(e, SOURCE_CHILD); - if (!s) - return -ENOMEM; - - s->child.pid = pid; - s->child.options = options; - s->child.callback = callback; - s->userdata = userdata; - s->enabled = SD_EVENT_ONESHOT; - - r = hashmap_put(e->child_sources, INT_TO_PTR(pid), s); - if (r < 0) { - source_free(s); - return r; - } - - e->n_enabled_child_sources ++; - - assert_se(sigaddset(&e->sigset, SIGCHLD) == 0); - - if (!e->signal_sources || !e->signal_sources[SIGCHLD]) { - r = event_update_signal_fd(e); - if (r < 0) { - source_free(s); - return -errno; - } - } - - e->need_process_child = true; - - *ret = s; - return 0; -} - -_public_ int sd_event_add_defer( - sd_event *e, - sd_event_handler_t callback, - void *userdata, - sd_event_source **ret) { - - sd_event_source *s; - int r; - - assert_return(e, -EINVAL); - assert_return(callback, -EINVAL); - assert_return(ret, -EINVAL); - assert_return(e->state != SD_EVENT_FINISHED, -ESTALE); - assert_return(!event_pid_changed(e), -ECHILD); - - s = source_new(e, SOURCE_DEFER); - if (!s) - return -ENOMEM; - - s->defer.callback = callback; - s->userdata = userdata; - s->enabled = SD_EVENT_ONESHOT; - - r = source_set_pending(s, true); - if (r < 0) { - source_free(s); - return r; - } - - *ret = s; - return 0; -} - -_public_ int sd_event_add_exit( - sd_event *e, - sd_event_handler_t callback, - void *userdata, - sd_event_source **ret) { - - sd_event_source *s; - int r; - - assert_return(e, -EINVAL); - assert_return(callback, -EINVAL); - assert_return(ret, -EINVAL); - assert_return(e->state != SD_EVENT_FINISHED, -ESTALE); - assert_return(!event_pid_changed(e), -ECHILD); - - if (!e->exit) { - e->exit = prioq_new(exit_prioq_compare); - if (!e->exit) - return -ENOMEM; - } - - s = source_new(e, SOURCE_EXIT); - if (!s) - return -ENOMEM; - - s->exit.callback = callback; - s->userdata = userdata; - s->exit.prioq_index = PRIOQ_IDX_NULL; - s->enabled = SD_EVENT_ONESHOT; - - r = prioq_put(s->event->exit, s, &s->exit.prioq_index); - if (r < 0) { - source_free(s); - return r; - } - - *ret = s; - return 0; -} - -_public_ sd_event_source* sd_event_source_ref(sd_event_source *s) { - assert_return(s, NULL); - - assert(s->n_ref >= 1); - s->n_ref++; - - return s; -} - -_public_ sd_event_source* sd_event_source_unref(sd_event_source *s) { - - if (!s) - return NULL; - - assert(s->n_ref >= 1); - s->n_ref--; - - if (s->n_ref <= 0) { - /* Here's a special hack: when we are called from a - * dispatch handler we won't free the event source - * immediately, but we will detach the fd from the - * epoll. This way it is safe for the caller to unref - * the event source and immediately close the fd, but - * we still retain a valid event source object after - * the callback. */ - - if (s->dispatching) { - if (s->type == SOURCE_IO) - source_io_unregister(s); - } else - source_free(s); - } - - return NULL; -} - -_public_ sd_event *sd_event_source_get_event(sd_event_source *s) { - assert_return(s, NULL); - - return s->event; -} - -_public_ int sd_event_source_get_pending(sd_event_source *s) { - assert_return(s, -EINVAL); - assert_return(s->type != SOURCE_EXIT, -EDOM); - assert_return(s->event->state != SD_EVENT_FINISHED, -ESTALE); - assert_return(!event_pid_changed(s->event), -ECHILD); - - return s->pending; -} - -_public_ int sd_event_source_get_io_fd(sd_event_source *s) { - assert_return(s, -EINVAL); - assert_return(s->type == SOURCE_IO, -EDOM); - assert_return(!event_pid_changed(s->event), -ECHILD); - - return s->io.fd; -} - -_public_ int sd_event_source_set_io_fd(sd_event_source *s, int fd) { - int r; - - assert_return(s, -EINVAL); - assert_return(fd >= 0, -EINVAL); - assert_return(s->type == SOURCE_IO, -EDOM); - assert_return(!event_pid_changed(s->event), -ECHILD); - - if (s->io.fd == fd) - return 0; - - if (s->enabled == SD_EVENT_OFF) { - s->io.fd = fd; - s->io.registered = false; - } else { - int saved_fd; - - saved_fd = s->io.fd; - assert(s->io.registered); - - s->io.fd = fd; - s->io.registered = false; - - r = source_io_register(s, s->enabled, s->io.events); - if (r < 0) { - s->io.fd = saved_fd; - s->io.registered = true; - return r; - } - - epoll_ctl(s->event->epoll_fd, EPOLL_CTL_DEL, saved_fd, NULL); - } - - return 0; -} - -_public_ int sd_event_source_get_io_events(sd_event_source *s, uint32_t* events) { - assert_return(s, -EINVAL); - assert_return(events, -EINVAL); - assert_return(s->type == SOURCE_IO, -EDOM); - assert_return(!event_pid_changed(s->event), -ECHILD); - - *events = s->io.events; - return 0; -} - -_public_ int sd_event_source_set_io_events(sd_event_source *s, uint32_t events) { - int r; - - assert_return(s, -EINVAL); - assert_return(s->type == SOURCE_IO, -EDOM); - assert_return(!(events & ~(EPOLLIN|EPOLLOUT|EPOLLRDHUP|EPOLLPRI|EPOLLERR|EPOLLHUP|EPOLLET)), -EINVAL); - assert_return(s->event->state != SD_EVENT_FINISHED, -ESTALE); - assert_return(!event_pid_changed(s->event), -ECHILD); - - if (s->io.events == events) - return 0; - - if (s->enabled != SD_EVENT_OFF) { - r = source_io_register(s, s->enabled, events); - if (r < 0) - return r; - } - - s->io.events = events; - source_set_pending(s, false); - - return 0; -} - -_public_ int sd_event_source_get_io_revents(sd_event_source *s, uint32_t* revents) { - assert_return(s, -EINVAL); - assert_return(revents, -EINVAL); - assert_return(s->type == SOURCE_IO, -EDOM); - assert_return(s->pending, -ENODATA); - assert_return(!event_pid_changed(s->event), -ECHILD); - - *revents = s->io.revents; - return 0; -} - -_public_ int sd_event_source_get_signal(sd_event_source *s) { - assert_return(s, -EINVAL); - assert_return(s->type == SOURCE_SIGNAL, -EDOM); - assert_return(!event_pid_changed(s->event), -ECHILD); - - return s->signal.sig; -} - -_public_ int sd_event_source_get_priority(sd_event_source *s, int64_t *priority) { - assert_return(s, -EINVAL); - assert_return(!event_pid_changed(s->event), -ECHILD); - - return s->priority; -} - -_public_ int sd_event_source_set_priority(sd_event_source *s, int64_t priority) { - assert_return(s, -EINVAL); - assert_return(s->event->state != SD_EVENT_FINISHED, -ESTALE); - assert_return(!event_pid_changed(s->event), -ECHILD); - - if (s->priority == priority) - return 0; - - s->priority = priority; - - if (s->pending) - prioq_reshuffle(s->event->pending, s, &s->pending_index); - - if (s->prepare) - prioq_reshuffle(s->event->prepare, s, &s->prepare_index); - - if (s->type == SOURCE_EXIT) - prioq_reshuffle(s->event->exit, s, &s->exit.prioq_index); - - return 0; -} - -_public_ int sd_event_source_get_enabled(sd_event_source *s, int *m) { - assert_return(s, -EINVAL); - assert_return(m, -EINVAL); - assert_return(!event_pid_changed(s->event), -ECHILD); - - *m = s->enabled; - return 0; -} - -_public_ int sd_event_source_set_enabled(sd_event_source *s, int m) { - int r; - - assert_return(s, -EINVAL); - assert_return(m == SD_EVENT_OFF || m == SD_EVENT_ON || m == SD_EVENT_ONESHOT, -EINVAL); - assert_return(s->event->state != SD_EVENT_FINISHED, -ESTALE); - assert_return(!event_pid_changed(s->event), -ECHILD); - - if (s->enabled == m) - return 0; - - if (m == SD_EVENT_OFF) { - - switch (s->type) { - - case SOURCE_IO: - r = source_io_unregister(s); - if (r < 0) - return r; - - s->enabled = m; - break; - - case SOURCE_MONOTONIC: - s->enabled = m; - prioq_reshuffle(s->event->monotonic_earliest, s, &s->time.earliest_index); - prioq_reshuffle(s->event->monotonic_latest, s, &s->time.latest_index); - break; - - case SOURCE_REALTIME: - s->enabled = m; - prioq_reshuffle(s->event->realtime_earliest, s, &s->time.earliest_index); - prioq_reshuffle(s->event->realtime_latest, s, &s->time.latest_index); - break; - - case SOURCE_SIGNAL: - s->enabled = m; - if (s->signal.sig != SIGCHLD || s->event->n_enabled_child_sources == 0) { - assert_se(sigdelset(&s->event->sigset, s->signal.sig) == 0); - event_update_signal_fd(s->event); - } - - break; - - case SOURCE_CHILD: - s->enabled = m; - - assert(s->event->n_enabled_child_sources > 0); - s->event->n_enabled_child_sources--; - - if (!s->event->signal_sources || !s->event->signal_sources[SIGCHLD]) { - assert_se(sigdelset(&s->event->sigset, SIGCHLD) == 0); - event_update_signal_fd(s->event); - } - - break; - - case SOURCE_EXIT: - s->enabled = m; - prioq_reshuffle(s->event->exit, s, &s->exit.prioq_index); - break; - - case SOURCE_DEFER: - s->enabled = m; - break; - - case SOURCE_WATCHDOG: - assert_not_reached("Wut? I shouldn't exist."); - } - - } else { - switch (s->type) { - - case SOURCE_IO: - r = source_io_register(s, m, s->io.events); - if (r < 0) - return r; - - s->enabled = m; - break; - - case SOURCE_MONOTONIC: - s->enabled = m; - prioq_reshuffle(s->event->monotonic_earliest, s, &s->time.earliest_index); - prioq_reshuffle(s->event->monotonic_latest, s, &s->time.latest_index); - break; - - case SOURCE_REALTIME: - s->enabled = m; - prioq_reshuffle(s->event->realtime_earliest, s, &s->time.earliest_index); - prioq_reshuffle(s->event->realtime_latest, s, &s->time.latest_index); - break; - - case SOURCE_SIGNAL: - s->enabled = m; - - if (s->signal.sig != SIGCHLD || s->event->n_enabled_child_sources == 0) { - assert_se(sigaddset(&s->event->sigset, s->signal.sig) == 0); - event_update_signal_fd(s->event); - } - break; - - case SOURCE_CHILD: - s->enabled = m; - - if (s->enabled == SD_EVENT_OFF) { - s->event->n_enabled_child_sources++; - - if (!s->event->signal_sources || !s->event->signal_sources[SIGCHLD]) { - assert_se(sigaddset(&s->event->sigset, SIGCHLD) == 0); - event_update_signal_fd(s->event); - } - } - break; - - case SOURCE_EXIT: - s->enabled = m; - prioq_reshuffle(s->event->exit, s, &s->exit.prioq_index); - break; - - case SOURCE_DEFER: - s->enabled = m; - break; - - case SOURCE_WATCHDOG: - assert_not_reached("Wut? I shouldn't exist."); - } - } - - if (s->pending) - prioq_reshuffle(s->event->pending, s, &s->pending_index); - - if (s->prepare) - prioq_reshuffle(s->event->prepare, s, &s->prepare_index); - - return 0; -} - -_public_ int sd_event_source_get_time(sd_event_source *s, uint64_t *usec) { - assert_return(s, -EINVAL); - assert_return(usec, -EINVAL); - assert_return(s->type == SOURCE_REALTIME || s->type == SOURCE_MONOTONIC, -EDOM); - assert_return(!event_pid_changed(s->event), -ECHILD); - - *usec = s->time.next; - return 0; -} - -_public_ int sd_event_source_set_time(sd_event_source *s, uint64_t usec) { - assert_return(s, -EINVAL); - assert_return(usec != (uint64_t) -1, -EINVAL); - assert_return(s->type == SOURCE_REALTIME || s->type == SOURCE_MONOTONIC, -EDOM); - assert_return(s->event->state != SD_EVENT_FINISHED, -ESTALE); - assert_return(!event_pid_changed(s->event), -ECHILD); - - s->time.next = usec; - - source_set_pending(s, false); - - if (s->type == SOURCE_REALTIME) { - prioq_reshuffle(s->event->realtime_earliest, s, &s->time.earliest_index); - prioq_reshuffle(s->event->realtime_latest, s, &s->time.latest_index); - } else { - prioq_reshuffle(s->event->monotonic_earliest, s, &s->time.earliest_index); - prioq_reshuffle(s->event->monotonic_latest, s, &s->time.latest_index); - } - - return 0; -} - -_public_ int sd_event_source_get_time_accuracy(sd_event_source *s, uint64_t *usec) { - assert_return(s, -EINVAL); - assert_return(usec, -EINVAL); - assert_return(s->type == SOURCE_REALTIME || s->type == SOURCE_MONOTONIC, -EDOM); - assert_return(!event_pid_changed(s->event), -ECHILD); - - *usec = s->time.accuracy; - return 0; -} - -_public_ int sd_event_source_set_time_accuracy(sd_event_source *s, uint64_t usec) { - assert_return(s, -EINVAL); - assert_return(usec != (uint64_t) -1, -EINVAL); - assert_return(s->type == SOURCE_REALTIME || s->type == SOURCE_MONOTONIC, -EDOM); - assert_return(s->event->state != SD_EVENT_FINISHED, -ESTALE); - assert_return(!event_pid_changed(s->event), -ECHILD); - - if (usec == 0) - usec = DEFAULT_ACCURACY_USEC; - - s->time.accuracy = usec; - - source_set_pending(s, false); - - if (s->type == SOURCE_REALTIME) - prioq_reshuffle(s->event->realtime_latest, s, &s->time.latest_index); - else - prioq_reshuffle(s->event->monotonic_latest, s, &s->time.latest_index); - - return 0; -} - -_public_ int sd_event_source_get_child_pid(sd_event_source *s, pid_t *pid) { - assert_return(s, -EINVAL); - assert_return(pid, -EINVAL); - assert_return(s->type == SOURCE_CHILD, -EDOM); - assert_return(!event_pid_changed(s->event), -ECHILD); - - *pid = s->child.pid; - return 0; -} - -_public_ int sd_event_source_set_prepare(sd_event_source *s, sd_event_handler_t callback) { - int r; - - assert_return(s, -EINVAL); - assert_return(s->type != SOURCE_EXIT, -EDOM); - assert_return(s->event->state != SD_EVENT_FINISHED, -ESTALE); - assert_return(!event_pid_changed(s->event), -ECHILD); - - if (s->prepare == callback) - return 0; - - if (callback && s->prepare) { - s->prepare = callback; - return 0; - } - - r = prioq_ensure_allocated(&s->event->prepare, prepare_prioq_compare); - if (r < 0) - return r; - - s->prepare = callback; - - if (callback) { - r = prioq_put(s->event->prepare, s, &s->prepare_index); - if (r < 0) - return r; - } else - prioq_remove(s->event->prepare, s, &s->prepare_index); - - return 0; -} - -_public_ void* sd_event_source_get_userdata(sd_event_source *s) { - assert_return(s, NULL); - - return s->userdata; -} - -_public_ void *sd_event_source_set_userdata(sd_event_source *s, void *userdata) { - void *ret; - - assert_return(s, NULL); - - ret = s->userdata; - s->userdata = userdata; - - return ret; -} - -static usec_t sleep_between(sd_event *e, usec_t a, usec_t b) { - usec_t c; - assert(e); - assert(a <= b); - - if (a <= 0) - return 0; - - if (b <= a + 1) - return a; - - /* - Find a good time to wake up again between times a and b. We - have two goals here: - - a) We want to wake up as seldom as possible, hence prefer - later times over earlier times. - - b) But if we have to wake up, then let's make sure to - dispatch as much as possible on the entire system. - - We implement this by waking up everywhere at the same time - within any given minute if we can, synchronised via the - perturbation value determined from the boot ID. If we can't, - then we try to find the same spot in every 10s, then 1s and - then 250ms step. Otherwise, we pick the last possible time - to wake up. - */ - - c = (b / USEC_PER_MINUTE) * USEC_PER_MINUTE + e->perturb; - if (c >= b) { - if (_unlikely_(c < USEC_PER_MINUTE)) - return b; - - c -= USEC_PER_MINUTE; - } - - if (c >= a) - return c; - - c = (b / (USEC_PER_SEC*10)) * (USEC_PER_SEC*10) + (e->perturb % (USEC_PER_SEC*10)); - if (c >= b) { - if (_unlikely_(c < USEC_PER_SEC*10)) - return b; - - c -= USEC_PER_SEC*10; - } - - if (c >= a) - return c; - - c = (b / USEC_PER_SEC) * USEC_PER_SEC + (e->perturb % USEC_PER_SEC); - if (c >= b) { - if (_unlikely_(c < USEC_PER_SEC)) - return b; - - c -= USEC_PER_SEC; - } - - if (c >= a) - return c; - - c = (b / (USEC_PER_MSEC*250)) * (USEC_PER_MSEC*250) + (e->perturb % (USEC_PER_MSEC*250)); - if (c >= b) { - if (_unlikely_(c < USEC_PER_MSEC*250)) - return b; - - c -= USEC_PER_MSEC*250; - } - - if (c >= a) - return c; - - return b; -} - -static int event_arm_timer( - sd_event *e, - int timer_fd, - Prioq *earliest, - Prioq *latest, - usec_t *next) { - - struct itimerspec its = {}; - sd_event_source *a, *b; - usec_t t; - int r; - - assert(e); - assert(next); - - a = prioq_peek(earliest); - if (!a || a->enabled == SD_EVENT_OFF) { - - if (timer_fd < 0) - return 0; - - if (*next == (usec_t) -1) - return 0; - - /* disarm */ - r = timerfd_settime(timer_fd, TFD_TIMER_ABSTIME, &its, NULL); - if (r < 0) - return r; - - *next = (usec_t) -1; - - return 0; - } - - b = prioq_peek(latest); - assert_se(b && b->enabled != SD_EVENT_OFF); - - t = sleep_between(e, a->time.next, b->time.next + b->time.accuracy); - if (*next == t) - return 0; - - assert_se(timer_fd >= 0); - - if (t == 0) { - /* We don' want to disarm here, just mean some time looooong ago. */ - its.it_value.tv_sec = 0; - its.it_value.tv_nsec = 1; - } else - timespec_store(&its.it_value, t); - - r = timerfd_settime(timer_fd, TFD_TIMER_ABSTIME, &its, NULL); - if (r < 0) - return -errno; - - *next = t; - return 0; -} - -static int process_io(sd_event *e, sd_event_source *s, uint32_t revents) { - assert(e); - assert(s); - assert(s->type == SOURCE_IO); - - /* If the event source was already pending, we just OR in the - * new revents, otherwise we reset the value. The ORing is - * necessary to handle EPOLLONESHOT events properly where - * readability might happen independently of writability, and - * we need to keep track of both */ - - if (s->pending) - s->io.revents |= revents; - else - s->io.revents = revents; - - return source_set_pending(s, true); -} - -static int flush_timer(sd_event *e, int fd, uint32_t events, usec_t *next) { - uint64_t x; - ssize_t ss; - - assert(e); - assert(fd >= 0); - - assert_return(events == EPOLLIN, -EIO); - - ss = read(fd, &x, sizeof(x)); - if (ss < 0) { - if (errno == EAGAIN || errno == EINTR) - return 0; - - return -errno; - } - - if (_unlikely_(ss != sizeof(x))) - return -EIO; - - if (next) - *next = (usec_t) -1; - - return 0; -} - -static int process_timer( - sd_event *e, - usec_t n, - Prioq *earliest, - Prioq *latest) { - - sd_event_source *s; - int r; - - assert(e); - - for (;;) { - s = prioq_peek(earliest); - if (!s || - s->time.next > n || - s->enabled == SD_EVENT_OFF || - s->pending) - break; - - r = source_set_pending(s, true); - if (r < 0) - return r; - - prioq_reshuffle(earliest, s, &s->time.earliest_index); - prioq_reshuffle(latest, s, &s->time.latest_index); - } - - return 0; -} - -static int process_child(sd_event *e) { - sd_event_source *s; - Iterator i; - int r; - - assert(e); - - e->need_process_child = false; - - /* - So, this is ugly. We iteratively invoke waitid() with P_PID - + WNOHANG for each PID we wait for, instead of using - P_ALL. This is because we only want to get child - information of very specific child processes, and not all - of them. We might not have processed the SIGCHLD even of a - previous invocation and we don't want to maintain a - unbounded *per-child* event queue, hence we really don't - want anything flushed out of the kernel's queue that we - don't care about. Since this is O(n) this means that if you - have a lot of processes you probably want to handle SIGCHLD - yourself. - - We do not reap the children here (by using WNOWAIT), this - is only done after the event source is dispatched so that - the callback still sees the process as a zombie. - */ - - HASHMAP_FOREACH(s, e->child_sources, i) { - assert(s->type == SOURCE_CHILD); - - if (s->pending) - continue; - - if (s->enabled == SD_EVENT_OFF) - continue; - - zero(s->child.siginfo); - r = waitid(P_PID, s->child.pid, &s->child.siginfo, - WNOHANG | (s->child.options & WEXITED ? WNOWAIT : 0) | s->child.options); - if (r < 0) - return -errno; - - if (s->child.siginfo.si_pid != 0) { - bool zombie = - s->child.siginfo.si_code == CLD_EXITED || - s->child.siginfo.si_code == CLD_KILLED || - s->child.siginfo.si_code == CLD_DUMPED; - - if (!zombie && (s->child.options & WEXITED)) { - /* If the child isn't dead then let's - * immediately remove the state change - * from the queue, since there's no - * benefit in leaving it queued */ - - assert(s->child.options & (WSTOPPED|WCONTINUED)); - waitid(P_PID, s->child.pid, &s->child.siginfo, WNOHANG|(s->child.options & (WSTOPPED|WCONTINUED))); - } - - r = source_set_pending(s, true); - if (r < 0) - return r; - } - } - - return 0; -} - -static int process_signal(sd_event *e, uint32_t events) { - bool read_one = false; - int r; - - assert(e); - assert(e->signal_sources); - - assert_return(events == EPOLLIN, -EIO); - - for (;;) { - struct signalfd_siginfo si; - ssize_t ss; - sd_event_source *s; - - ss = read(e->signal_fd, &si, sizeof(si)); - if (ss < 0) { - if (errno == EAGAIN || errno == EINTR) - return read_one; - - return -errno; - } - - if (_unlikely_(ss != sizeof(si))) - return -EIO; - - read_one = true; - - s = e->signal_sources[si.ssi_signo]; - if (si.ssi_signo == SIGCHLD) { - r = process_child(e); - if (r < 0) - return r; - if (r > 0 || !s) - continue; - } else - if (!s) - return -EIO; - - s->signal.siginfo = si; - r = source_set_pending(s, true); - if (r < 0) - return r; - } - - return 0; -} - -static int source_dispatch(sd_event_source *s) { - int r = 0; - - assert(s); - assert(s->pending || s->type == SOURCE_EXIT); - - if (s->type != SOURCE_DEFER && s->type != SOURCE_EXIT) { - r = source_set_pending(s, false); - if (r < 0) - return r; - } - - if (s->enabled == SD_EVENT_ONESHOT) { - r = sd_event_source_set_enabled(s, SD_EVENT_OFF); - if (r < 0) - return r; - } - - s->dispatching = true; - - switch (s->type) { - - case SOURCE_IO: - r = s->io.callback(s, s->io.fd, s->io.revents, s->userdata); - break; - - case SOURCE_MONOTONIC: - r = s->time.callback(s, s->time.next, s->userdata); - break; - - case SOURCE_REALTIME: - r = s->time.callback(s, s->time.next, s->userdata); - break; - - case SOURCE_SIGNAL: - r = s->signal.callback(s, &s->signal.siginfo, s->userdata); - break; - - case SOURCE_CHILD: { - bool zombie; - - zombie = s->child.siginfo.si_code == CLD_EXITED || - s->child.siginfo.si_code == CLD_KILLED || - s->child.siginfo.si_code == CLD_DUMPED; - - r = s->child.callback(s, &s->child.siginfo, s->userdata); - - /* Now, reap the PID for good. */ - if (zombie) - waitid(P_PID, s->child.pid, &s->child.siginfo, WNOHANG|WEXITED); - - break; - } - - case SOURCE_DEFER: - r = s->defer.callback(s, s->userdata); - break; - - case SOURCE_EXIT: - r = s->exit.callback(s, s->userdata); - break; - - case SOURCE_WATCHDOG: - assert_not_reached("Wut? I shouldn't exist."); - } - - s->dispatching = false; - - if (r < 0) - log_debug("Event source %p returned error, disabling: %s", s, strerror(-r)); - - if (s->n_ref == 0) - source_free(s); - else if (r < 0) - sd_event_source_set_enabled(s, SD_EVENT_OFF); - - return 1; -} - -static int event_prepare(sd_event *e) { - int r; - - assert(e); - - for (;;) { - sd_event_source *s; - - s = prioq_peek(e->prepare); - if (!s || s->prepare_iteration == e->iteration || s->enabled == SD_EVENT_OFF) - break; - - s->prepare_iteration = e->iteration; - r = prioq_reshuffle(e->prepare, s, &s->prepare_index); - if (r < 0) - return r; - - assert(s->prepare); - - s->dispatching = true; - r = s->prepare(s, s->userdata); - s->dispatching = false; - - if (r < 0) - log_debug("Prepare callback of event source %p returned error, disabling: %s", s, strerror(-r)); - - if (s->n_ref == 0) - source_free(s); - else if (r < 0) - sd_event_source_set_enabled(s, SD_EVENT_OFF); - } - - return 0; -} - -static int dispatch_exit(sd_event *e) { - sd_event_source *p; - int r; - - assert(e); - - p = prioq_peek(e->exit); - if (!p || p->enabled == SD_EVENT_OFF) { - e->state = SD_EVENT_FINISHED; - return 0; - } - - sd_event_ref(e); - e->iteration++; - e->state = SD_EVENT_EXITING; - - r = source_dispatch(p); - - e->state = SD_EVENT_PASSIVE; - sd_event_unref(e); - - return r; -} - -static sd_event_source* event_next_pending(sd_event *e) { - sd_event_source *p; - - assert(e); - - p = prioq_peek(e->pending); - if (!p) - return NULL; - - if (p->enabled == SD_EVENT_OFF) - return NULL; - - return p; -} - -static int arm_watchdog(sd_event *e) { - struct itimerspec its = {}; - usec_t t; - int r; - - assert(e); - assert(e->watchdog_fd >= 0); - - t = sleep_between(e, - e->watchdog_last + (e->watchdog_period / 2), - e->watchdog_last + (e->watchdog_period * 3 / 4)); - - timespec_store(&its.it_value, t); - - r = timerfd_settime(e->watchdog_fd, TFD_TIMER_ABSTIME, &its, NULL); - if (r < 0) - return -errno; - - return 0; -} - -static int process_watchdog(sd_event *e) { - assert(e); - - if (!e->watchdog) - return 0; - - /* Don't notify watchdog too often */ - if (e->watchdog_last + e->watchdog_period / 4 > e->timestamp.monotonic) - return 0; - - sd_notify(false, "WATCHDOG=1"); - e->watchdog_last = e->timestamp.monotonic; - - return arm_watchdog(e); -} - -_public_ int sd_event_run(sd_event *e, uint64_t timeout) { - struct epoll_event *ev_queue; - unsigned ev_queue_max; - sd_event_source *p; - int r, i, m; - - assert_return(e, -EINVAL); - assert_return(!event_pid_changed(e), -ECHILD); - assert_return(e->state != SD_EVENT_FINISHED, -ESTALE); - assert_return(e->state == SD_EVENT_PASSIVE, -EBUSY); - - if (e->exit_requested) - return dispatch_exit(e); - - sd_event_ref(e); - e->iteration++; - e->state = SD_EVENT_RUNNING; - - r = event_prepare(e); - if (r < 0) - goto finish; - - r = event_arm_timer(e, e->monotonic_fd, e->monotonic_earliest, e->monotonic_latest, &e->monotonic_next); - if (r < 0) - goto finish; - - r = event_arm_timer(e, e->realtime_fd, e->realtime_earliest, e->realtime_latest, &e->realtime_next); - if (r < 0) - goto finish; - - if (event_next_pending(e) || e->need_process_child) - timeout = 0; - ev_queue_max = CLAMP(e->n_sources, 1U, EPOLL_QUEUE_MAX); - ev_queue = newa(struct epoll_event, ev_queue_max); - - m = epoll_wait(e->epoll_fd, ev_queue, ev_queue_max, - timeout == (uint64_t) -1 ? -1 : (int) ((timeout + USEC_PER_MSEC - 1) / USEC_PER_MSEC)); - if (m < 0) { - r = errno == EAGAIN || errno == EINTR ? 1 : -errno; - goto finish; - } - - dual_timestamp_get(&e->timestamp); - - for (i = 0; i < m; i++) { - - if (ev_queue[i].data.ptr == INT_TO_PTR(SOURCE_MONOTONIC)) - r = flush_timer(e, e->monotonic_fd, ev_queue[i].events, &e->monotonic_next); - else if (ev_queue[i].data.ptr == INT_TO_PTR(SOURCE_REALTIME)) - r = flush_timer(e, e->realtime_fd, ev_queue[i].events, &e->realtime_next); - else if (ev_queue[i].data.ptr == INT_TO_PTR(SOURCE_SIGNAL)) - r = process_signal(e, ev_queue[i].events); - else if (ev_queue[i].data.ptr == INT_TO_PTR(SOURCE_WATCHDOG)) - r = flush_timer(e, e->watchdog_fd, ev_queue[i].events, NULL); - else - r = process_io(e, ev_queue[i].data.ptr, ev_queue[i].events); - - if (r < 0) - goto finish; - } - - r = process_watchdog(e); - if (r < 0) - goto finish; - - r = process_timer(e, e->timestamp.monotonic, e->monotonic_earliest, e->monotonic_latest); - if (r < 0) - goto finish; - - r = process_timer(e, e->timestamp.realtime, e->realtime_earliest, e->realtime_latest); - if (r < 0) - goto finish; - - if (e->need_process_child) { - r = process_child(e); - if (r < 0) - goto finish; - } - - p = event_next_pending(e); - if (!p) { - r = 1; - goto finish; - } - - r = source_dispatch(p); - -finish: - e->state = SD_EVENT_PASSIVE; - sd_event_unref(e); - - return r; -} - -_public_ int sd_event_loop(sd_event *e) { - int r; - - assert_return(e, -EINVAL); - assert_return(!event_pid_changed(e), -ECHILD); - assert_return(e->state == SD_EVENT_PASSIVE, -EBUSY); - - sd_event_ref(e); - - while (e->state != SD_EVENT_FINISHED) { - r = sd_event_run(e, (uint64_t) -1); - if (r < 0) - goto finish; - } - - r = e->exit_code; - -finish: - sd_event_unref(e); - return r; -} - -_public_ int sd_event_get_state(sd_event *e) { - assert_return(e, -EINVAL); - assert_return(!event_pid_changed(e), -ECHILD); - - return e->state; -} - -_public_ int sd_event_get_exit_code(sd_event *e, int *code) { - assert_return(e, -EINVAL); - assert_return(code, -EINVAL); - assert_return(!event_pid_changed(e), -ECHILD); - - if (!e->exit_requested) - return -ENODATA; - - *code = e->exit_code; - return 0; -} - -_public_ int sd_event_exit(sd_event *e, int code) { - assert_return(e, -EINVAL); - assert_return(e->state != SD_EVENT_FINISHED, -ESTALE); - assert_return(!event_pid_changed(e), -ECHILD); - - e->exit_requested = true; - e->exit_code = code; - - return 0; -} - -_public_ int sd_event_get_now_realtime(sd_event *e, uint64_t *usec) { - assert_return(e, -EINVAL); - assert_return(usec, -EINVAL); - assert_return(dual_timestamp_is_set(&e->timestamp), -ENODATA); - assert_return(!event_pid_changed(e), -ECHILD); - - *usec = e->timestamp.realtime; - return 0; -} - -_public_ int sd_event_get_now_monotonic(sd_event *e, uint64_t *usec) { - assert_return(e, -EINVAL); - assert_return(usec, -EINVAL); - assert_return(dual_timestamp_is_set(&e->timestamp), -ENODATA); - assert_return(!event_pid_changed(e), -ECHILD); - - *usec = e->timestamp.monotonic; - return 0; -} - -_public_ int sd_event_default(sd_event **ret) { - - static thread_local sd_event *default_event = NULL; - sd_event *e; - int r; - - if (!ret) - return !!default_event; - - if (default_event) { - *ret = sd_event_ref(default_event); - return 0; - } - - r = sd_event_new(&e); - if (r < 0) - return r; - - e->default_event_ptr = &default_event; - e->tid = gettid(); - default_event = e; - - *ret = e; - return 1; -} - -_public_ int sd_event_get_tid(sd_event *e, pid_t *tid) { - assert_return(e, -EINVAL); - assert_return(tid, -EINVAL); - assert_return(!event_pid_changed(e), -ECHILD); - - if (e->tid != 0) { - *tid = e->tid; - return 0; - } - - return -ENXIO; -} - -_public_ int sd_event_set_watchdog(sd_event *e, int b) { - int r; - - assert_return(e, -EINVAL); - assert_return(!event_pid_changed(e), -ECHILD); - - if (e->watchdog == !!b) - return e->watchdog; - - if (b) { - struct epoll_event ev = {}; - - r = sd_watchdog_enabled(false, &e->watchdog_period); - if (r <= 0) - return r; - - /* Issue first ping immediately */ - sd_notify(false, "WATCHDOG=1"); - e->watchdog_last = now(CLOCK_MONOTONIC); - - e->watchdog_fd = timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK|TFD_CLOEXEC); - if (e->watchdog_fd < 0) - return -errno; - - r = arm_watchdog(e); - if (r < 0) - goto fail; - - ev.events = EPOLLIN; - ev.data.ptr = INT_TO_PTR(SOURCE_WATCHDOG); - - r = epoll_ctl(e->epoll_fd, EPOLL_CTL_ADD, e->watchdog_fd, &ev); - if (r < 0) { - r = -errno; - goto fail; - } - - } else { - if (e->watchdog_fd >= 0) { - epoll_ctl(e->epoll_fd, EPOLL_CTL_DEL, e->watchdog_fd, NULL); - close_nointr_nofail(e->watchdog_fd); - e->watchdog_fd = -1; - } - } - - e->watchdog = !!b; - return e->watchdog; - -fail: - close_nointr_nofail(e->watchdog_fd); - e->watchdog_fd = -1; - return r; -} - -_public_ int sd_event_get_watchdog(sd_event *e) { - assert_return(e, -EINVAL); - assert_return(!event_pid_changed(e), -ECHILD); - - return e->watchdog; -} |