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Diffstat (limited to 'src/libsystemd/libsystemd-internal/sd-event/sd-event.c')
-rw-r--r--src/libsystemd/libsystemd-internal/sd-event/sd-event.c2898
1 files changed, 2898 insertions, 0 deletions
diff --git a/src/libsystemd/libsystemd-internal/sd-event/sd-event.c b/src/libsystemd/libsystemd-internal/sd-event/sd-event.c
new file mode 100644
index 0000000000..7f6f485353
--- /dev/null
+++ b/src/libsystemd/libsystemd-internal/sd-event/sd-event.c
@@ -0,0 +1,2898 @@
+/***
+ 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 <systemd/sd-daemon.h>
+#include <systemd/sd-event.h>
+#include <systemd/sd-id128.h>
+
+#include "alloc-util.h"
+#include "fd-util.h"
+#include "hashmap.h"
+#include "list.h"
+#include "macro.h"
+#include "missing.h"
+#include "prioq.h"
+#include "process-util.h"
+#include "set.h"
+#include "signal-util.h"
+#include "string-table.h"
+#include "string-util.h"
+#include "time-util.h"
+#include "util.h"
+
+#define DEFAULT_ACCURACY_USEC (250 * USEC_PER_MSEC)
+
+typedef enum EventSourceType {
+ SOURCE_IO,
+ SOURCE_TIME_REALTIME,
+ SOURCE_TIME_BOOTTIME,
+ SOURCE_TIME_MONOTONIC,
+ SOURCE_TIME_REALTIME_ALARM,
+ SOURCE_TIME_BOOTTIME_ALARM,
+ SOURCE_SIGNAL,
+ SOURCE_CHILD,
+ SOURCE_DEFER,
+ SOURCE_POST,
+ SOURCE_EXIT,
+ SOURCE_WATCHDOG,
+ _SOURCE_EVENT_SOURCE_TYPE_MAX,
+ _SOURCE_EVENT_SOURCE_TYPE_INVALID = -1
+} EventSourceType;
+
+static const char* const event_source_type_table[_SOURCE_EVENT_SOURCE_TYPE_MAX] = {
+ [SOURCE_IO] = "io",
+ [SOURCE_TIME_REALTIME] = "realtime",
+ [SOURCE_TIME_BOOTTIME] = "bootime",
+ [SOURCE_TIME_MONOTONIC] = "monotonic",
+ [SOURCE_TIME_REALTIME_ALARM] = "realtime-alarm",
+ [SOURCE_TIME_BOOTTIME_ALARM] = "boottime-alarm",
+ [SOURCE_SIGNAL] = "signal",
+ [SOURCE_CHILD] = "child",
+ [SOURCE_DEFER] = "defer",
+ [SOURCE_POST] = "post",
+ [SOURCE_EXIT] = "exit",
+ [SOURCE_WATCHDOG] = "watchdog",
+};
+
+DEFINE_PRIVATE_STRING_TABLE_LOOKUP_TO_STRING(event_source_type, int);
+
+/* All objects we use in epoll events start with this value, so that
+ * we know how to dispatch it */
+typedef enum WakeupType {
+ WAKEUP_NONE,
+ WAKEUP_EVENT_SOURCE,
+ WAKEUP_CLOCK_DATA,
+ WAKEUP_SIGNAL_DATA,
+ _WAKEUP_TYPE_MAX,
+ _WAKEUP_TYPE_INVALID = -1,
+} WakeupType;
+
+#define EVENT_SOURCE_IS_TIME(t) IN_SET((t), SOURCE_TIME_REALTIME, SOURCE_TIME_BOOTTIME, SOURCE_TIME_MONOTONIC, SOURCE_TIME_REALTIME_ALARM, SOURCE_TIME_BOOTTIME_ALARM)
+
+struct sd_event_source {
+ WakeupType wakeup;
+
+ unsigned n_ref;
+
+ sd_event *event;
+ void *userdata;
+ sd_event_handler_t prepare;
+
+ char *description;
+
+ EventSourceType type:5;
+ int enabled:3;
+ bool pending:1;
+ bool dispatching:1;
+ bool floating:1;
+
+ int64_t priority;
+ unsigned pending_index;
+ unsigned prepare_index;
+ unsigned pending_iteration;
+ unsigned prepare_iteration;
+
+ LIST_FIELDS(sd_event_source, sources);
+
+ 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;
+ } post;
+ struct {
+ sd_event_handler_t callback;
+ unsigned prioq_index;
+ } exit;
+ };
+};
+
+struct clock_data {
+ WakeupType wakeup;
+ int fd;
+
+ /* For all 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 *earliest;
+ Prioq *latest;
+ usec_t next;
+
+ bool needs_rearm:1;
+};
+
+struct signal_data {
+ WakeupType wakeup;
+
+ /* For each priority we maintain one signal fd, so that we
+ * only have to dequeue a single event per priority at a
+ * time. */
+
+ int fd;
+ int64_t priority;
+ sigset_t sigset;
+ sd_event_source *current;
+};
+
+struct sd_event {
+ unsigned n_ref;
+
+ int epoll_fd;
+ int watchdog_fd;
+
+ Prioq *pending;
+ Prioq *prepare;
+
+ /* timerfd_create() only supports these five clocks so far. We
+ * can add support for more clocks when the kernel learns to
+ * deal with them, too. */
+ struct clock_data realtime;
+ struct clock_data boottime;
+ struct clock_data monotonic;
+ struct clock_data realtime_alarm;
+ struct clock_data boottime_alarm;
+
+ usec_t perturb;
+
+ sd_event_source **signal_sources; /* indexed by signal number */
+ Hashmap *signal_data; /* indexed by priority */
+
+ Hashmap *child_sources;
+ unsigned n_enabled_child_sources;
+
+ Set *post_sources;
+
+ Prioq *exit;
+
+ pid_t original_pid;
+
+ unsigned iteration;
+ dual_timestamp timestamp;
+ usec_t timestamp_boottime;
+ int state;
+
+ bool exit_requested:1;
+ bool need_process_child:1;
+ bool watchdog:1;
+ bool profile_delays:1;
+
+ int exit_code;
+
+ pid_t tid;
+ sd_event **default_event_ptr;
+
+ usec_t watchdog_last, watchdog_period;
+
+ unsigned n_sources;
+
+ LIST_HEAD(sd_event_source, sources);
+
+ usec_t last_run, last_log;
+ unsigned delays[sizeof(usec_t) * 8];
+};
+
+static void source_disconnect(sd_event_source *s);
+
+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;
+
+ 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);
+
+ /* 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 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;
+
+ /* Lower priority values first */
+ if (x->priority < y->priority)
+ return -1;
+ if (x->priority > y->priority)
+ 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(EVENT_SOURCE_IS_TIME(x->type));
+ assert(x->type == y->type);
+
+ /* 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;
+
+ return 0;
+}
+
+static usec_t time_event_source_latest(const sd_event_source *s) {
+ return usec_add(s->time.next, s->time.accuracy);
+}
+
+static int latest_time_prioq_compare(const void *a, const void *b) {
+ const sd_event_source *x = a, *y = b;
+
+ assert(EVENT_SOURCE_IS_TIME(x->type));
+ assert(x->type == y->type);
+
+ /* 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 (time_event_source_latest(x) < time_event_source_latest(y))
+ return -1;
+ if (time_event_source_latest(x) > time_event_source_latest(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;
+
+ return 0;
+}
+
+static void free_clock_data(struct clock_data *d) {
+ assert(d);
+ assert(d->wakeup == WAKEUP_CLOCK_DATA);
+
+ safe_close(d->fd);
+ prioq_free(d->earliest);
+ prioq_free(d->latest);
+}
+
+static void event_free(sd_event *e) {
+ sd_event_source *s;
+
+ assert(e);
+
+ while ((s = e->sources)) {
+ assert(s->floating);
+ source_disconnect(s);
+ sd_event_source_unref(s);
+ }
+
+ assert(e->n_sources == 0);
+
+ if (e->default_event_ptr)
+ *(e->default_event_ptr) = NULL;
+
+ safe_close(e->epoll_fd);
+ safe_close(e->watchdog_fd);
+
+ free_clock_data(&e->realtime);
+ free_clock_data(&e->boottime);
+ free_clock_data(&e->monotonic);
+ free_clock_data(&e->realtime_alarm);
+ free_clock_data(&e->boottime_alarm);
+
+ prioq_free(e->pending);
+ prioq_free(e->prepare);
+ prioq_free(e->exit);
+
+ free(e->signal_sources);
+ hashmap_free(e->signal_data);
+
+ hashmap_free(e->child_sources);
+ set_free(e->post_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->watchdog_fd = e->epoll_fd = e->realtime.fd = e->boottime.fd = e->monotonic.fd = e->realtime_alarm.fd = e->boottime_alarm.fd = -1;
+ e->realtime.next = e->boottime.next = e->monotonic.next = e->realtime_alarm.next = e->boottime_alarm.next = USEC_INFINITY;
+ e->realtime.wakeup = e->boottime.wakeup = e->monotonic.wakeup = e->realtime_alarm.wakeup = e->boottime_alarm.wakeup = WAKEUP_CLOCK_DATA;
+ e->original_pid = getpid();
+ e->perturb = USEC_INFINITY;
+
+ r = prioq_ensure_allocated(&e->pending, pending_prioq_compare);
+ if (r < 0)
+ goto fail;
+
+ e->epoll_fd = epoll_create1(EPOLL_CLOEXEC);
+ if (e->epoll_fd < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ if (secure_getenv("SD_EVENT_PROFILE_DELAYS")) {
+ log_debug("Event loop profiling enabled. Logarithmic histogram of event loop iterations in the range 2^0 ... 2^63 us will be logged every 5s.");
+ e->profile_delays = true;
+ }
+
+ *ret = e;
+ return 0;
+
+fail:
+ event_free(e);
+ return r;
+}
+
+_public_ sd_event* sd_event_ref(sd_event *e) {
+
+ if (!e)
+ return 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 an event loop and keeping
+ * it around over a fork(). Let's complain. */
+
+ return e->original_pid != getpid();
+}
+
+static void source_io_unregister(sd_event_source *s) {
+ int r;
+
+ assert(s);
+ assert(s->type == SOURCE_IO);
+
+ if (event_pid_changed(s->event))
+ return;
+
+ if (!s->io.registered)
+ return;
+
+ r = epoll_ctl(s->event->epoll_fd, EPOLL_CTL_DEL, s->io.fd, NULL);
+ if (r < 0)
+ log_debug_errno(errno, "Failed to remove source %s (type %s) from epoll: %m",
+ strna(s->description), event_source_type_to_string(s->type));
+
+ s->io.registered = false;
+}
+
+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 clockid_t event_source_type_to_clock(EventSourceType t) {
+
+ switch (t) {
+
+ case SOURCE_TIME_REALTIME:
+ return CLOCK_REALTIME;
+
+ case SOURCE_TIME_BOOTTIME:
+ return CLOCK_BOOTTIME;
+
+ case SOURCE_TIME_MONOTONIC:
+ return CLOCK_MONOTONIC;
+
+ case SOURCE_TIME_REALTIME_ALARM:
+ return CLOCK_REALTIME_ALARM;
+
+ case SOURCE_TIME_BOOTTIME_ALARM:
+ return CLOCK_BOOTTIME_ALARM;
+
+ default:
+ return (clockid_t) -1;
+ }
+}
+
+static EventSourceType clock_to_event_source_type(clockid_t clock) {
+
+ switch (clock) {
+
+ case CLOCK_REALTIME:
+ return SOURCE_TIME_REALTIME;
+
+ case CLOCK_BOOTTIME:
+ return SOURCE_TIME_BOOTTIME;
+
+ case CLOCK_MONOTONIC:
+ return SOURCE_TIME_MONOTONIC;
+
+ case CLOCK_REALTIME_ALARM:
+ return SOURCE_TIME_REALTIME_ALARM;
+
+ case CLOCK_BOOTTIME_ALARM:
+ return SOURCE_TIME_BOOTTIME_ALARM;
+
+ default:
+ return _SOURCE_EVENT_SOURCE_TYPE_INVALID;
+ }
+}
+
+static struct clock_data* event_get_clock_data(sd_event *e, EventSourceType t) {
+ assert(e);
+
+ switch (t) {
+
+ case SOURCE_TIME_REALTIME:
+ return &e->realtime;
+
+ case SOURCE_TIME_BOOTTIME:
+ return &e->boottime;
+
+ case SOURCE_TIME_MONOTONIC:
+ return &e->monotonic;
+
+ case SOURCE_TIME_REALTIME_ALARM:
+ return &e->realtime_alarm;
+
+ case SOURCE_TIME_BOOTTIME_ALARM:
+ return &e->boottime_alarm;
+
+ default:
+ return NULL;
+ }
+}
+
+static int event_make_signal_data(
+ sd_event *e,
+ int sig,
+ struct signal_data **ret) {
+
+ struct epoll_event ev = {};
+ struct signal_data *d;
+ bool added = false;
+ sigset_t ss_copy;
+ int64_t priority;
+ int r;
+
+ assert(e);
+
+ if (event_pid_changed(e))
+ return -ECHILD;
+
+ if (e->signal_sources && e->signal_sources[sig])
+ priority = e->signal_sources[sig]->priority;
+ else
+ priority = 0;
+
+ d = hashmap_get(e->signal_data, &priority);
+ if (d) {
+ if (sigismember(&d->sigset, sig) > 0) {
+ if (ret)
+ *ret = d;
+ return 0;
+ }
+ } else {
+ r = hashmap_ensure_allocated(&e->signal_data, &uint64_hash_ops);
+ if (r < 0)
+ return r;
+
+ d = new0(struct signal_data, 1);
+ if (!d)
+ return -ENOMEM;
+
+ d->wakeup = WAKEUP_SIGNAL_DATA;
+ d->fd = -1;
+ d->priority = priority;
+
+ r = hashmap_put(e->signal_data, &d->priority, d);
+ if (r < 0) {
+ free(d);
+ return r;
+ }
+
+ added = true;
+ }
+
+ ss_copy = d->sigset;
+ assert_se(sigaddset(&ss_copy, sig) >= 0);
+
+ r = signalfd(d->fd, &ss_copy, SFD_NONBLOCK|SFD_CLOEXEC);
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ d->sigset = ss_copy;
+
+ if (d->fd >= 0) {
+ if (ret)
+ *ret = d;
+ return 0;
+ }
+
+ d->fd = r;
+
+ ev.events = EPOLLIN;
+ ev.data.ptr = d;
+
+ r = epoll_ctl(e->epoll_fd, EPOLL_CTL_ADD, d->fd, &ev);
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ if (ret)
+ *ret = d;
+
+ return 0;
+
+fail:
+ if (added) {
+ d->fd = safe_close(d->fd);
+ hashmap_remove(e->signal_data, &d->priority);
+ free(d);
+ }
+
+ return r;
+}
+
+static void event_unmask_signal_data(sd_event *e, struct signal_data *d, int sig) {
+ assert(e);
+ assert(d);
+
+ /* Turns off the specified signal in the signal data
+ * object. If the signal mask of the object becomes empty that
+ * way removes it. */
+
+ if (sigismember(&d->sigset, sig) == 0)
+ return;
+
+ assert_se(sigdelset(&d->sigset, sig) >= 0);
+
+ if (sigisemptyset(&d->sigset)) {
+
+ /* If all the mask is all-zero we can get rid of the structure */
+ hashmap_remove(e->signal_data, &d->priority);
+ assert(!d->current);
+ safe_close(d->fd);
+ free(d);
+ return;
+ }
+
+ assert(d->fd >= 0);
+
+ if (signalfd(d->fd, &d->sigset, SFD_NONBLOCK|SFD_CLOEXEC) < 0)
+ log_debug_errno(errno, "Failed to unset signal bit, ignoring: %m");
+}
+
+static void event_gc_signal_data(sd_event *e, const int64_t *priority, int sig) {
+ struct signal_data *d;
+ static const int64_t zero_priority = 0;
+
+ assert(e);
+
+ /* Rechecks if the specified signal is still something we are
+ * interested in. If not, we'll unmask it, and possibly drop
+ * the signalfd for it. */
+
+ if (sig == SIGCHLD &&
+ e->n_enabled_child_sources > 0)
+ return;
+
+ if (e->signal_sources &&
+ e->signal_sources[sig] &&
+ e->signal_sources[sig]->enabled != SD_EVENT_OFF)
+ return;
+
+ /*
+ * The specified signal might be enabled in three different queues:
+ *
+ * 1) the one that belongs to the priority passed (if it is non-NULL)
+ * 2) the one that belongs to the priority of the event source of the signal (if there is one)
+ * 3) the 0 priority (to cover the SIGCHLD case)
+ *
+ * Hence, let's remove it from all three here.
+ */
+
+ if (priority) {
+ d = hashmap_get(e->signal_data, priority);
+ if (d)
+ event_unmask_signal_data(e, d, sig);
+ }
+
+ if (e->signal_sources && e->signal_sources[sig]) {
+ d = hashmap_get(e->signal_data, &e->signal_sources[sig]->priority);
+ if (d)
+ event_unmask_signal_data(e, d, sig);
+ }
+
+ d = hashmap_get(e->signal_data, &zero_priority);
+ if (d)
+ event_unmask_signal_data(e, d, sig);
+}
+
+static void source_disconnect(sd_event_source *s) {
+ sd_event *event;
+
+ assert(s);
+
+ if (!s->event)
+ return;
+
+ assert(s->event->n_sources > 0);
+
+ switch (s->type) {
+
+ case SOURCE_IO:
+ if (s->io.fd >= 0)
+ source_io_unregister(s);
+
+ break;
+
+ case SOURCE_TIME_REALTIME:
+ case SOURCE_TIME_BOOTTIME:
+ case SOURCE_TIME_MONOTONIC:
+ case SOURCE_TIME_REALTIME_ALARM:
+ case SOURCE_TIME_BOOTTIME_ALARM: {
+ struct clock_data *d;
+
+ d = event_get_clock_data(s->event, s->type);
+ assert(d);
+
+ prioq_remove(d->earliest, s, &s->time.earliest_index);
+ prioq_remove(d->latest, s, &s->time.latest_index);
+ d->needs_rearm = true;
+ break;
+ }
+
+ case SOURCE_SIGNAL:
+ if (s->signal.sig > 0) {
+
+ if (s->event->signal_sources)
+ s->event->signal_sources[s->signal.sig] = NULL;
+
+ event_gc_signal_data(s->event, &s->priority, s->signal.sig);
+ }
+
+ 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--;
+ }
+
+ (void) hashmap_remove(s->event->child_sources, PID_TO_PTR(s->child.pid));
+ event_gc_signal_data(s->event, &s->priority, SIGCHLD);
+ }
+
+ break;
+
+ case SOURCE_DEFER:
+ /* nothing */
+ break;
+
+ case SOURCE_POST:
+ set_remove(s->event->post_sources, s);
+ break;
+
+ case SOURCE_EXIT:
+ prioq_remove(s->event->exit, s, &s->exit.prioq_index);
+ break;
+
+ default:
+ 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);
+
+ event = s->event;
+
+ s->type = _SOURCE_EVENT_SOURCE_TYPE_INVALID;
+ s->event = NULL;
+ LIST_REMOVE(sources, event->sources, s);
+ event->n_sources--;
+
+ if (!s->floating)
+ sd_event_unref(event);
+}
+
+static void source_free(sd_event_source *s) {
+ assert(s);
+
+ source_disconnect(s);
+ free(s->description);
+ 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 (EVENT_SOURCE_IS_TIME(s->type)) {
+ struct clock_data *d;
+
+ d = event_get_clock_data(s->event, s->type);
+ assert(d);
+
+ prioq_reshuffle(d->earliest, s, &s->time.earliest_index);
+ prioq_reshuffle(d->latest, s, &s->time.latest_index);
+ d->needs_rearm = true;
+ }
+
+ if (s->type == SOURCE_SIGNAL && !b) {
+ struct signal_data *d;
+
+ d = hashmap_get(s->event->signal_data, &s->priority);
+ if (d && d->current == s)
+ d->current = NULL;
+ }
+
+ return 0;
+}
+
+static sd_event_source *source_new(sd_event *e, bool floating, EventSourceType type) {
+ sd_event_source *s;
+
+ assert(e);
+
+ s = new0(sd_event_source, 1);
+ if (!s)
+ return NULL;
+
+ s->n_ref = 1;
+ s->event = e;
+ s->floating = floating;
+ s->type = type;
+ s->pending_index = s->prepare_index = PRIOQ_IDX_NULL;
+
+ if (!floating)
+ sd_event_ref(e);
+
+ LIST_PREPEND(sources, e->sources, s);
+ e->n_sources++;
+
+ return s;
+}
+
+_public_ int sd_event_add_io(
+ sd_event *e,
+ sd_event_source **ret,
+ int fd,
+ uint32_t events,
+ sd_event_io_handler_t callback,
+ void *userdata) {
+
+ sd_event_source *s;
+ int r;
+
+ assert_return(e, -EINVAL);
+ assert_return(fd >= 0, -EBADF);
+ assert_return(!(events & ~(EPOLLIN|EPOLLOUT|EPOLLRDHUP|EPOLLPRI|EPOLLERR|EPOLLHUP|EPOLLET)), -EINVAL);
+ assert_return(callback, -EINVAL);
+ assert_return(e->state != SD_EVENT_FINISHED, -ESTALE);
+ assert_return(!event_pid_changed(e), -ECHILD);
+
+ s = source_new(e, !ret, SOURCE_IO);
+ if (!s)
+ return -ENOMEM;
+
+ s->wakeup = WAKEUP_EVENT_SOURCE;
+ 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 r;
+ }
+
+ if (ret)
+ *ret = s;
+
+ return 0;
+}
+
+static void initialize_perturb(sd_event *e) {
+ sd_id128_t bootid = {};
+
+ /* 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 (_likely_(e->perturb != USEC_INFINITY))
+ return;
+
+ if (sd_id128_get_boot(&bootid) >= 0)
+ e->perturb = (bootid.qwords[0] ^ bootid.qwords[1]) % USEC_PER_MINUTE;
+}
+
+static int event_setup_timer_fd(
+ sd_event *e,
+ struct clock_data *d,
+ clockid_t clock) {
+
+ struct epoll_event ev = {};
+ int r, fd;
+
+ assert(e);
+ assert(d);
+
+ if (_likely_(d->fd >= 0))
+ return 0;
+
+ fd = timerfd_create(clock, TFD_NONBLOCK|TFD_CLOEXEC);
+ if (fd < 0)
+ return -errno;
+
+ ev.events = EPOLLIN;
+ ev.data.ptr = d;
+
+ r = epoll_ctl(e->epoll_fd, EPOLL_CTL_ADD, fd, &ev);
+ if (r < 0) {
+ safe_close(fd);
+ return -errno;
+ }
+
+ d->fd = fd;
+ return 0;
+}
+
+static int time_exit_callback(sd_event_source *s, uint64_t usec, void *userdata) {
+ assert(s);
+
+ return sd_event_exit(sd_event_source_get_event(s), PTR_TO_INT(userdata));
+}
+
+_public_ int sd_event_add_time(
+ sd_event *e,
+ sd_event_source **ret,
+ clockid_t clock,
+ uint64_t usec,
+ uint64_t accuracy,
+ sd_event_time_handler_t callback,
+ void *userdata) {
+
+ EventSourceType type;
+ sd_event_source *s;
+ struct clock_data *d;
+ int r;
+
+ assert_return(e, -EINVAL);
+ assert_return(accuracy != (uint64_t) -1, -EINVAL);
+ assert_return(e->state != SD_EVENT_FINISHED, -ESTALE);
+ assert_return(!event_pid_changed(e), -ECHILD);
+
+ if (IN_SET(clock, CLOCK_BOOTTIME, CLOCK_BOOTTIME_ALARM) &&
+ !clock_boottime_supported())
+ return -EOPNOTSUPP;
+
+ if (!callback)
+ callback = time_exit_callback;
+
+ type = clock_to_event_source_type(clock);
+ assert_return(type >= 0, -EOPNOTSUPP);
+
+ d = event_get_clock_data(e, type);
+ assert(d);
+
+ r = prioq_ensure_allocated(&d->earliest, earliest_time_prioq_compare);
+ if (r < 0)
+ return r;
+
+ r = prioq_ensure_allocated(&d->latest, latest_time_prioq_compare);
+ if (r < 0)
+ return r;
+
+ if (d->fd < 0) {
+ r = event_setup_timer_fd(e, d, clock);
+ if (r < 0)
+ return r;
+ }
+
+ s = source_new(e, !ret, 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;
+
+ d->needs_rearm = true;
+
+ r = prioq_put(d->earliest, s, &s->time.earliest_index);
+ if (r < 0)
+ goto fail;
+
+ r = prioq_put(d->latest, s, &s->time.latest_index);
+ if (r < 0)
+ goto fail;
+
+ if (ret)
+ *ret = s;
+
+ return 0;
+
+fail:
+ source_free(s);
+ return r;
+}
+
+static int signal_exit_callback(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {
+ assert(s);
+
+ return sd_event_exit(sd_event_source_get_event(s), PTR_TO_INT(userdata));
+}
+
+_public_ int sd_event_add_signal(
+ sd_event *e,
+ sd_event_source **ret,
+ int sig,
+ sd_event_signal_handler_t callback,
+ void *userdata) {
+
+ sd_event_source *s;
+ struct signal_data *d;
+ sigset_t ss;
+ int r;
+
+ assert_return(e, -EINVAL);
+ assert_return(SIGNAL_VALID(sig), -EINVAL);
+ assert_return(e->state != SD_EVENT_FINISHED, -ESTALE);
+ assert_return(!event_pid_changed(e), -ECHILD);
+
+ if (!callback)
+ callback = signal_exit_callback;
+
+ r = pthread_sigmask(SIG_SETMASK, NULL, &ss);
+ if (r != 0)
+ return -r;
+
+ 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, !ret, 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;
+
+ r = event_make_signal_data(e, sig, &d);
+ if (r < 0) {
+ source_free(s);
+ return r;
+ }
+
+ /* Use the signal name as description for the event source by default */
+ (void) sd_event_source_set_description(s, signal_to_string(sig));
+
+ if (ret)
+ *ret = s;
+
+ return 0;
+}
+
+_public_ int sd_event_add_child(
+ sd_event *e,
+ sd_event_source **ret,
+ pid_t pid,
+ int options,
+ sd_event_child_handler_t callback,
+ void *userdata) {
+
+ 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(e->state != SD_EVENT_FINISHED, -ESTALE);
+ assert_return(!event_pid_changed(e), -ECHILD);
+
+ r = hashmap_ensure_allocated(&e->child_sources, NULL);
+ if (r < 0)
+ return r;
+
+ if (hashmap_contains(e->child_sources, PID_TO_PTR(pid)))
+ return -EBUSY;
+
+ s = source_new(e, !ret, 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, PID_TO_PTR(pid), s);
+ if (r < 0) {
+ source_free(s);
+ return r;
+ }
+
+ e->n_enabled_child_sources++;
+
+ r = event_make_signal_data(e, SIGCHLD, NULL);
+ if (r < 0) {
+ e->n_enabled_child_sources--;
+ source_free(s);
+ return r;
+ }
+
+ e->need_process_child = true;
+
+ if (ret)
+ *ret = s;
+
+ return 0;
+}
+
+_public_ int sd_event_add_defer(
+ sd_event *e,
+ sd_event_source **ret,
+ sd_event_handler_t callback,
+ void *userdata) {
+
+ sd_event_source *s;
+ int r;
+
+ assert_return(e, -EINVAL);
+ assert_return(callback, -EINVAL);
+ assert_return(e->state != SD_EVENT_FINISHED, -ESTALE);
+ assert_return(!event_pid_changed(e), -ECHILD);
+
+ s = source_new(e, !ret, 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;
+ }
+
+ if (ret)
+ *ret = s;
+
+ return 0;
+}
+
+_public_ int sd_event_add_post(
+ sd_event *e,
+ sd_event_source **ret,
+ sd_event_handler_t callback,
+ void *userdata) {
+
+ sd_event_source *s;
+ int r;
+
+ assert_return(e, -EINVAL);
+ assert_return(callback, -EINVAL);
+ assert_return(e->state != SD_EVENT_FINISHED, -ESTALE);
+ assert_return(!event_pid_changed(e), -ECHILD);
+
+ r = set_ensure_allocated(&e->post_sources, NULL);
+ if (r < 0)
+ return r;
+
+ s = source_new(e, !ret, SOURCE_POST);
+ if (!s)
+ return -ENOMEM;
+
+ s->post.callback = callback;
+ s->userdata = userdata;
+ s->enabled = SD_EVENT_ON;
+
+ r = set_put(e->post_sources, s);
+ if (r < 0) {
+ source_free(s);
+ return r;
+ }
+
+ if (ret)
+ *ret = s;
+
+ return 0;
+}
+
+_public_ int sd_event_add_exit(
+ sd_event *e,
+ sd_event_source **ret,
+ sd_event_handler_t callback,
+ void *userdata) {
+
+ sd_event_source *s;
+ int r;
+
+ assert_return(e, -EINVAL);
+ assert_return(callback, -EINVAL);
+ assert_return(e->state != SD_EVENT_FINISHED, -ESTALE);
+ assert_return(!event_pid_changed(e), -ECHILD);
+
+ r = prioq_ensure_allocated(&e->exit, exit_prioq_compare);
+ if (r < 0)
+ return r;
+
+ s = source_new(e, !ret, 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;
+ }
+
+ if (ret)
+ *ret = s;
+
+ return 0;
+}
+
+_public_ sd_event_source* sd_event_source_ref(sd_event_source *s) {
+
+ if (!s)
+ return 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);
+
+ source_disconnect(s);
+ } else
+ source_free(s);
+ }
+
+ return NULL;
+}
+
+_public_ int sd_event_source_set_description(sd_event_source *s, const char *description) {
+ assert_return(s, -EINVAL);
+ assert_return(!event_pid_changed(s->event), -ECHILD);
+
+ return free_and_strdup(&s->description, description);
+}
+
+_public_ int sd_event_source_get_description(sd_event_source *s, const char **description) {
+ assert_return(s, -EINVAL);
+ assert_return(description, -EINVAL);
+ assert_return(s->description, -ENXIO);
+ assert_return(!event_pid_changed(s->event), -ECHILD);
+
+ *description = s->description;
+ return 0;
+}
+
+_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, -EBADF);
+ 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);
+
+ /* edge-triggered updates are never skipped, so we can reset edges */
+ if (s->io.events == events && !(events & EPOLLET))
+ 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) {
+ int r;
+
+ 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;
+
+ if (s->type == SOURCE_SIGNAL && s->enabled != SD_EVENT_OFF) {
+ struct signal_data *old, *d;
+
+ /* Move us from the signalfd belonging to the old
+ * priority to the signalfd of the new priority */
+
+ assert_se(old = hashmap_get(s->event->signal_data, &s->priority));
+
+ s->priority = priority;
+
+ r = event_make_signal_data(s->event, s->signal.sig, &d);
+ if (r < 0) {
+ s->priority = old->priority;
+ return r;
+ }
+
+ event_unmask_signal_data(s->event, old, s->signal.sig);
+ } else
+ 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(!event_pid_changed(s->event), -ECHILD);
+
+ /* If we are dead anyway, we are fine with turning off
+ * sources, but everything else needs to fail. */
+ if (s->event->state == SD_EVENT_FINISHED)
+ return m == SD_EVENT_OFF ? 0 : -ESTALE;
+
+ if (s->enabled == m)
+ return 0;
+
+ if (m == SD_EVENT_OFF) {
+
+ switch (s->type) {
+
+ case SOURCE_IO:
+ source_io_unregister(s);
+ s->enabled = m;
+ break;
+
+ case SOURCE_TIME_REALTIME:
+ case SOURCE_TIME_BOOTTIME:
+ case SOURCE_TIME_MONOTONIC:
+ case SOURCE_TIME_REALTIME_ALARM:
+ case SOURCE_TIME_BOOTTIME_ALARM: {
+ struct clock_data *d;
+
+ s->enabled = m;
+ d = event_get_clock_data(s->event, s->type);
+ assert(d);
+
+ prioq_reshuffle(d->earliest, s, &s->time.earliest_index);
+ prioq_reshuffle(d->latest, s, &s->time.latest_index);
+ d->needs_rearm = true;
+ break;
+ }
+
+ case SOURCE_SIGNAL:
+ s->enabled = m;
+
+ event_gc_signal_data(s->event, &s->priority, s->signal.sig);
+ break;
+
+ case SOURCE_CHILD:
+ s->enabled = m;
+
+ assert(s->event->n_enabled_child_sources > 0);
+ s->event->n_enabled_child_sources--;
+
+ event_gc_signal_data(s->event, &s->priority, SIGCHLD);
+ break;
+
+ case SOURCE_EXIT:
+ s->enabled = m;
+ prioq_reshuffle(s->event->exit, s, &s->exit.prioq_index);
+ break;
+
+ case SOURCE_DEFER:
+ case SOURCE_POST:
+ s->enabled = m;
+ break;
+
+ default:
+ 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_TIME_REALTIME:
+ case SOURCE_TIME_BOOTTIME:
+ case SOURCE_TIME_MONOTONIC:
+ case SOURCE_TIME_REALTIME_ALARM:
+ case SOURCE_TIME_BOOTTIME_ALARM: {
+ struct clock_data *d;
+
+ s->enabled = m;
+ d = event_get_clock_data(s->event, s->type);
+ assert(d);
+
+ prioq_reshuffle(d->earliest, s, &s->time.earliest_index);
+ prioq_reshuffle(d->latest, s, &s->time.latest_index);
+ d->needs_rearm = true;
+ break;
+ }
+
+ case SOURCE_SIGNAL:
+
+ s->enabled = m;
+
+ r = event_make_signal_data(s->event, s->signal.sig, NULL);
+ if (r < 0) {
+ s->enabled = SD_EVENT_OFF;
+ event_gc_signal_data(s->event, &s->priority, s->signal.sig);
+ return r;
+ }
+
+ break;
+
+ case SOURCE_CHILD:
+
+ if (s->enabled == SD_EVENT_OFF)
+ s->event->n_enabled_child_sources++;
+
+ s->enabled = m;
+
+ r = event_make_signal_data(s->event, SIGCHLD, NULL);
+ if (r < 0) {
+ s->enabled = SD_EVENT_OFF;
+ s->event->n_enabled_child_sources--;
+ event_gc_signal_data(s->event, &s->priority, SIGCHLD);
+ return r;
+ }
+
+ break;
+
+ case SOURCE_EXIT:
+ s->enabled = m;
+ prioq_reshuffle(s->event->exit, s, &s->exit.prioq_index);
+ break;
+
+ case SOURCE_DEFER:
+ case SOURCE_POST:
+ s->enabled = m;
+ break;
+
+ default:
+ 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(EVENT_SOURCE_IS_TIME(s->type), -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) {
+ struct clock_data *d;
+
+ assert_return(s, -EINVAL);
+ assert_return(EVENT_SOURCE_IS_TIME(s->type), -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);
+
+ d = event_get_clock_data(s->event, s->type);
+ assert(d);
+
+ prioq_reshuffle(d->earliest, s, &s->time.earliest_index);
+ prioq_reshuffle(d->latest, s, &s->time.latest_index);
+ d->needs_rearm = true;
+
+ 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(EVENT_SOURCE_IS_TIME(s->type), -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) {
+ struct clock_data *d;
+
+ assert_return(s, -EINVAL);
+ assert_return(usec != (uint64_t) -1, -EINVAL);
+ assert_return(EVENT_SOURCE_IS_TIME(s->type), -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);
+
+ d = event_get_clock_data(s->event, s->type);
+ assert(d);
+
+ prioq_reshuffle(d->latest, s, &s->time.latest_index);
+ d->needs_rearm = true;
+
+ return 0;
+}
+
+_public_ int sd_event_source_get_time_clock(sd_event_source *s, clockid_t *clock) {
+ assert_return(s, -EINVAL);
+ assert_return(clock, -EINVAL);
+ assert_return(EVENT_SOURCE_IS_TIME(s->type), -EDOM);
+ assert_return(!event_pid_changed(s->event), -ECHILD);
+
+ *clock = event_source_type_to_clock(s->type);
+ 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 (a >= USEC_INFINITY)
+ return USEC_INFINITY;
+
+ if (b <= a + 1)
+ return a;
+
+ initialize_perturb(e);
+
+ /*
+ 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,
+ struct clock_data *d) {
+
+ struct itimerspec its = {};
+ sd_event_source *a, *b;
+ usec_t t;
+ int r;
+
+ assert(e);
+ assert(d);
+
+ if (!d->needs_rearm)
+ return 0;
+ else
+ d->needs_rearm = false;
+
+ a = prioq_peek(d->earliest);
+ if (!a || a->enabled == SD_EVENT_OFF || a->time.next == USEC_INFINITY) {
+
+ if (d->fd < 0)
+ return 0;
+
+ if (d->next == USEC_INFINITY)
+ return 0;
+
+ /* disarm */
+ r = timerfd_settime(d->fd, TFD_TIMER_ABSTIME, &its, NULL);
+ if (r < 0)
+ return r;
+
+ d->next = USEC_INFINITY;
+ return 0;
+ }
+
+ b = prioq_peek(d->latest);
+ assert_se(b && b->enabled != SD_EVENT_OFF);
+
+ t = sleep_between(e, a->time.next, time_event_source_latest(b));
+ if (d->next == t)
+ return 0;
+
+ assert_se(d->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(d->fd, TFD_TIMER_ABSTIME, &its, NULL);
+ if (r < 0)
+ return -errno;
+
+ d->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_INFINITY;
+
+ return 0;
+}
+
+static int process_timer(
+ sd_event *e,
+ usec_t n,
+ struct clock_data *d) {
+
+ sd_event_source *s;
+ int r;
+
+ assert(e);
+ assert(d);
+
+ for (;;) {
+ s = prioq_peek(d->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(d->earliest, s, &s->time.earliest_index);
+ prioq_reshuffle(d->latest, s, &s->time.latest_index);
+ d->needs_rearm = true;
+ }
+
+ 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, struct signal_data *d, uint32_t events) {
+ bool read_one = false;
+ int r;
+
+ assert(e);
+ assert_return(events == EPOLLIN, -EIO);
+
+ /* If there's a signal queued on this priority and SIGCHLD is
+ on this priority too, then make sure to recheck the
+ children we watch. This is because we only ever dequeue
+ the first signal per priority, and if we dequeue one, and
+ SIGCHLD might be enqueued later we wouldn't know, but we
+ might have higher priority children we care about hence we
+ need to check that explicitly. */
+
+ if (sigismember(&d->sigset, SIGCHLD))
+ e->need_process_child = true;
+
+ /* If there's already an event source pending for this
+ * priority we don't read another */
+ if (d->current)
+ return 0;
+
+ for (;;) {
+ struct signalfd_siginfo si;
+ ssize_t n;
+ sd_event_source *s = NULL;
+
+ n = read(d->fd, &si, sizeof(si));
+ if (n < 0) {
+ if (errno == EAGAIN || errno == EINTR)
+ return read_one;
+
+ return -errno;
+ }
+
+ if (_unlikely_(n != sizeof(si)))
+ return -EIO;
+
+ assert(SIGNAL_VALID(si.ssi_signo));
+
+ read_one = true;
+
+ if (e->signal_sources)
+ s = e->signal_sources[si.ssi_signo];
+ if (!s)
+ continue;
+ if (s->pending)
+ continue;
+
+ s->signal.siginfo = si;
+ d->current = s;
+
+ r = source_set_pending(s, true);
+ if (r < 0)
+ return r;
+
+ return 1;
+ }
+}
+
+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->type != SOURCE_POST) {
+ sd_event_source *z;
+ Iterator i;
+
+ /* If we execute a non-post source, let's mark all
+ * post sources as pending */
+
+ SET_FOREACH(z, s->event->post_sources, i) {
+ if (z->enabled == SD_EVENT_OFF)
+ continue;
+
+ r = source_set_pending(z, true);
+ 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_TIME_REALTIME:
+ case SOURCE_TIME_BOOTTIME:
+ case SOURCE_TIME_MONOTONIC:
+ case SOURCE_TIME_REALTIME_ALARM:
+ case SOURCE_TIME_BOOTTIME_ALARM:
+ 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_POST:
+ r = s->post.callback(s, s->userdata);
+ break;
+
+ case SOURCE_EXIT:
+ r = s->exit.callback(s, s->userdata);
+ break;
+
+ case SOURCE_WATCHDOG:
+ case _SOURCE_EVENT_SOURCE_TYPE_MAX:
+ case _SOURCE_EVENT_SOURCE_TYPE_INVALID:
+ assert_not_reached("Wut? I shouldn't exist.");
+ }
+
+ s->dispatching = false;
+
+ if (r < 0)
+ log_debug_errno(r, "Event source %s (type %s) returned error, disabling: %m",
+ strna(s->description), event_source_type_to_string(s->type));
+
+ 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_errno(r, "Prepare callback of event source %s (type %s) returned error, disabling: %m",
+ strna(s->description), event_source_type_to_string(s->type));
+
+ 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_INITIAL;
+ 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);
+
+ /* Make sure we never set the watchdog to 0, which tells the
+ * kernel to disable it. */
+ if (its.it_value.tv_sec == 0 && its.it_value.tv_nsec == 0)
+ its.it_value.tv_nsec = 1;
+
+ 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_prepare(sd_event *e) {
+ int r;
+
+ 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_INITIAL, -EBUSY);
+
+ if (e->exit_requested)
+ goto pending;
+
+ e->iteration++;
+
+ e->state = SD_EVENT_PREPARING;
+ r = event_prepare(e);
+ e->state = SD_EVENT_INITIAL;
+ if (r < 0)
+ return r;
+
+ r = event_arm_timer(e, &e->realtime);
+ if (r < 0)
+ return r;
+
+ r = event_arm_timer(e, &e->boottime);
+ if (r < 0)
+ return r;
+
+ r = event_arm_timer(e, &e->monotonic);
+ if (r < 0)
+ return r;
+
+ r = event_arm_timer(e, &e->realtime_alarm);
+ if (r < 0)
+ return r;
+
+ r = event_arm_timer(e, &e->boottime_alarm);
+ if (r < 0)
+ return r;
+
+ if (event_next_pending(e) || e->need_process_child)
+ goto pending;
+
+ e->state = SD_EVENT_ARMED;
+
+ return 0;
+
+pending:
+ e->state = SD_EVENT_ARMED;
+ r = sd_event_wait(e, 0);
+ if (r == 0)
+ e->state = SD_EVENT_ARMED;
+
+ return r;
+}
+
+_public_ int sd_event_wait(sd_event *e, uint64_t timeout) {
+ struct epoll_event *ev_queue;
+ unsigned ev_queue_max;
+ int r, m, i;
+
+ 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_ARMED, -EBUSY);
+
+ if (e->exit_requested) {
+ e->state = SD_EVENT_PENDING;
+ return 1;
+ }
+
+ ev_queue_max = MAX(e->n_sources, 1u);
+ 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) {
+ if (errno == EINTR) {
+ e->state = SD_EVENT_PENDING;
+ return 1;
+ }
+
+ r = -errno;
+ goto finish;
+ }
+
+ dual_timestamp_get(&e->timestamp);
+ if (clock_boottime_supported())
+ e->timestamp_boottime = now(CLOCK_BOOTTIME);
+
+ for (i = 0; i < m; i++) {
+
+ if (ev_queue[i].data.ptr == INT_TO_PTR(SOURCE_WATCHDOG))
+ r = flush_timer(e, e->watchdog_fd, ev_queue[i].events, NULL);
+ else {
+ WakeupType *t = ev_queue[i].data.ptr;
+
+ switch (*t) {
+
+ case WAKEUP_EVENT_SOURCE:
+ r = process_io(e, ev_queue[i].data.ptr, ev_queue[i].events);
+ break;
+
+ case WAKEUP_CLOCK_DATA: {
+ struct clock_data *d = ev_queue[i].data.ptr;
+ r = flush_timer(e, d->fd, ev_queue[i].events, &d->next);
+ break;
+ }
+
+ case WAKEUP_SIGNAL_DATA:
+ r = process_signal(e, ev_queue[i].data.ptr, ev_queue[i].events);
+ break;
+
+ default:
+ assert_not_reached("Invalid wake-up pointer");
+ }
+ }
+ if (r < 0)
+ goto finish;
+ }
+
+ r = process_watchdog(e);
+ if (r < 0)
+ goto finish;
+
+ r = process_timer(e, e->timestamp.realtime, &e->realtime);
+ if (r < 0)
+ goto finish;
+
+ r = process_timer(e, e->timestamp_boottime, &e->boottime);
+ if (r < 0)
+ goto finish;
+
+ r = process_timer(e, e->timestamp.monotonic, &e->monotonic);
+ if (r < 0)
+ goto finish;
+
+ r = process_timer(e, e->timestamp.realtime, &e->realtime_alarm);
+ if (r < 0)
+ goto finish;
+
+ r = process_timer(e, e->timestamp_boottime, &e->boottime_alarm);
+ if (r < 0)
+ goto finish;
+
+ if (e->need_process_child) {
+ r = process_child(e);
+ if (r < 0)
+ goto finish;
+ }
+
+ if (event_next_pending(e)) {
+ e->state = SD_EVENT_PENDING;
+
+ return 1;
+ }
+
+ r = 0;
+
+finish:
+ e->state = SD_EVENT_INITIAL;
+
+ return r;
+}
+
+_public_ int sd_event_dispatch(sd_event *e) {
+ sd_event_source *p;
+ int r;
+
+ 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_PENDING, -EBUSY);
+
+ if (e->exit_requested)
+ return dispatch_exit(e);
+
+ p = event_next_pending(e);
+ if (p) {
+ sd_event_ref(e);
+
+ e->state = SD_EVENT_RUNNING;
+ r = source_dispatch(p);
+ e->state = SD_EVENT_INITIAL;
+
+ sd_event_unref(e);
+
+ return r;
+ }
+
+ e->state = SD_EVENT_INITIAL;
+
+ return 1;
+}
+
+static void event_log_delays(sd_event *e) {
+ char b[ELEMENTSOF(e->delays) * DECIMAL_STR_MAX(unsigned) + 1];
+ unsigned i;
+ int o;
+
+ for (i = o = 0; i < ELEMENTSOF(e->delays); i++) {
+ o += snprintf(&b[o], sizeof(b) - o, "%u ", e->delays[i]);
+ e->delays[i] = 0;
+ }
+ log_debug("Event loop iterations: %.*s", o, b);
+}
+
+_public_ int sd_event_run(sd_event *e, uint64_t timeout) {
+ int r;
+
+ 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_INITIAL, -EBUSY);
+
+ if (e->profile_delays && e->last_run) {
+ usec_t this_run;
+ unsigned l;
+
+ this_run = now(CLOCK_MONOTONIC);
+
+ l = u64log2(this_run - e->last_run);
+ assert(l < sizeof(e->delays));
+ e->delays[l]++;
+
+ if (this_run - e->last_log >= 5*USEC_PER_SEC) {
+ event_log_delays(e);
+ e->last_log = this_run;
+ }
+ }
+
+ r = sd_event_prepare(e);
+ if (r == 0)
+ /* There was nothing? Then wait... */
+ r = sd_event_wait(e, timeout);
+
+ if (e->profile_delays)
+ e->last_run = now(CLOCK_MONOTONIC);
+
+ if (r > 0) {
+ /* There's something now, then let's dispatch it */
+ r = sd_event_dispatch(e);
+ if (r < 0)
+ return r;
+
+ return 1;
+ }
+
+ 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_INITIAL, -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_fd(sd_event *e) {
+
+ assert_return(e, -EINVAL);
+ assert_return(!event_pid_changed(e), -ECHILD);
+
+ return e->epoll_fd;
+}
+
+_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_now(sd_event *e, clockid_t clock, uint64_t *usec) {
+ assert_return(e, -EINVAL);
+ assert_return(usec, -EINVAL);
+ assert_return(!event_pid_changed(e), -ECHILD);
+ assert_return(IN_SET(clock,
+ CLOCK_REALTIME,
+ CLOCK_REALTIME_ALARM,
+ CLOCK_MONOTONIC,
+ CLOCK_BOOTTIME,
+ CLOCK_BOOTTIME_ALARM), -EOPNOTSUPP);
+
+ if (IN_SET(clock, CLOCK_BOOTTIME, CLOCK_BOOTTIME_ALARM) && !clock_boottime_supported())
+ return -EOPNOTSUPP;
+
+ if (!dual_timestamp_is_set(&e->timestamp)) {
+ /* Implicitly fall back to now() if we never ran
+ * before and thus have no cached time. */
+ *usec = now(clock);
+ return 1;
+ }
+
+ switch (clock) {
+
+ case CLOCK_REALTIME:
+ case CLOCK_REALTIME_ALARM:
+ *usec = e->timestamp.realtime;
+ break;
+
+ case CLOCK_MONOTONIC:
+ *usec = e->timestamp.monotonic;
+ break;
+
+ case CLOCK_BOOTTIME:
+ case CLOCK_BOOTTIME_ALARM:
+ *usec = e->timestamp_boottime;
+ break;
+
+ default:
+ assert_not_reached("Unknown clock?");
+ }
+
+ return 0;
+}
+
+_public_ int sd_event_default(sd_event **ret) {
+
+ static thread_local sd_event *default_event = NULL;
+ sd_event *e = NULL;
+ 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);
+ e->watchdog_fd = safe_close(e->watchdog_fd);
+ }
+ }
+
+ e->watchdog = !!b;
+ return e->watchdog;
+
+fail:
+ e->watchdog_fd = safe_close(e->watchdog_fd);
+ 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;
+}