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-rw-r--r--src/libsystemd/sd-event/sd-event.c4010
1 files changed, 4010 insertions, 0 deletions
diff --git a/src/libsystemd/sd-event/sd-event.c b/src/libsystemd/sd-event/sd-event.c
new file mode 100644
index 0000000..789a8c7
--- /dev/null
+++ b/src/libsystemd/sd-event/sd-event.c
@@ -0,0 +1,4010 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <sys/epoll.h>
+#include <sys/timerfd.h>
+#include <sys/wait.h>
+
+#include "sd-daemon.h"
+#include "sd-event.h"
+#include "sd-id128.h"
+
+#include "alloc-util.h"
+#include "env-util.h"
+#include "event-source.h"
+#include "fd-util.h"
+#include "fs-util.h"
+#include "hashmap.h"
+#include "list.h"
+#include "macro.h"
+#include "memory-util.h"
+#include "missing_syscall.h"
+#include "prioq.h"
+#include "process-util.h"
+#include "set.h"
+#include "signal-util.h"
+#include "string-table.h"
+#include "string-util.h"
+#include "strxcpyx.h"
+#include "time-util.h"
+
+#define DEFAULT_ACCURACY_USEC (250 * USEC_PER_MSEC)
+
+static bool EVENT_SOURCE_WATCH_PIDFD(sd_event_source *s) {
+ /* Returns true if this is a PID event source and can be implemented by watching EPOLLIN */
+ return s &&
+ s->type == SOURCE_CHILD &&
+ s->child.pidfd >= 0 &&
+ s->child.options == WEXITED;
+}
+
+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",
+ [SOURCE_INOTIFY] = "inotify",
+};
+
+DEFINE_PRIVATE_STRING_TABLE_LOOKUP_TO_STRING(event_source_type, int);
+
+#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 {
+ 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;
+
+ Hashmap *inotify_data; /* indexed by priority */
+
+ /* A list of inode structures that still have an fd open, that we need to close before the next loop iteration */
+ LIST_HEAD(struct inode_data, inode_data_to_close);
+
+ /* A list of inotify objects that already have events buffered which aren't processed yet */
+ LIST_HEAD(struct inotify_data, inotify_data_buffered);
+
+ pid_t original_pid;
+
+ uint64_t iteration;
+ triple_timestamp timestamp;
+ 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;
+
+ struct epoll_event *event_queue;
+ size_t event_queue_allocated;
+
+ LIST_HEAD(sd_event_source, sources);
+
+ usec_t last_run, last_log;
+ unsigned delays[sizeof(usec_t) * 8];
+};
+
+static thread_local sd_event *default_event = NULL;
+
+static void source_disconnect(sd_event_source *s);
+static void event_gc_inode_data(sd_event *e, struct inode_data *d);
+
+static sd_event *event_resolve(sd_event *e) {
+ return e == SD_EVENT_DEFAULT ? default_event : e;
+}
+
+static int pending_prioq_compare(const void *a, const void *b) {
+ const sd_event_source *x = a, *y = b;
+ int r;
+
+ 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 */
+ r = CMP(x->priority, y->priority);
+ if (r != 0)
+ return r;
+
+ /* Older entries first */
+ return CMP(x->pending_iteration, y->pending_iteration);
+}
+
+static int prepare_prioq_compare(const void *a, const void *b) {
+ const sd_event_source *x = a, *y = b;
+ int r;
+
+ 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 */
+ r = CMP(x->prepare_iteration, y->prepare_iteration);
+ if (r != 0)
+ return r;
+
+ /* Lower priority values first */
+ return CMP(x->priority, y->priority);
+}
+
+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 */
+ return CMP(x->time.next, y->time.next);
+}
+
+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 */
+ return CMP(time_event_source_latest(x), time_event_source_latest(y));
+}
+
+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 */
+ return CMP(x->priority, y->priority);
+}
+
+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 sd_event *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->inotify_data);
+
+ hashmap_free(e->child_sources);
+ set_free(e->post_sources);
+
+ free(e->event_queue);
+
+ return mfree(e);
+}
+
+_public_ int sd_event_new(sd_event** ret) {
+ sd_event *e;
+ int r;
+
+ assert_return(ret, -EINVAL);
+
+ e = new(sd_event, 1);
+ if (!e)
+ return -ENOMEM;
+
+ *e = (sd_event) {
+ .n_ref = 1,
+ .epoll_fd = -1,
+ .watchdog_fd = -1,
+ .realtime.wakeup = WAKEUP_CLOCK_DATA,
+ .realtime.fd = -1,
+ .realtime.next = USEC_INFINITY,
+ .boottime.wakeup = WAKEUP_CLOCK_DATA,
+ .boottime.fd = -1,
+ .boottime.next = USEC_INFINITY,
+ .monotonic.wakeup = WAKEUP_CLOCK_DATA,
+ .monotonic.fd = -1,
+ .monotonic.next = USEC_INFINITY,
+ .realtime_alarm.wakeup = WAKEUP_CLOCK_DATA,
+ .realtime_alarm.fd = -1,
+ .realtime_alarm.next = USEC_INFINITY,
+ .boottime_alarm.wakeup = WAKEUP_CLOCK_DATA,
+ .boottime_alarm.fd = -1,
+ .boottime_alarm.next = USEC_INFINITY,
+ .perturb = USEC_INFINITY,
+ .original_pid = getpid_cached(),
+ };
+
+ 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;
+ }
+
+ e->epoll_fd = fd_move_above_stdio(e->epoll_fd);
+
+ 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;
+}
+
+DEFINE_PUBLIC_TRIVIAL_REF_UNREF_FUNC(sd_event, sd_event, event_free);
+
+_public_ sd_event_source* sd_event_source_disable_unref(sd_event_source *s) {
+ if (s)
+ (void) sd_event_source_set_enabled(s, SD_EVENT_OFF);
+ return sd_event_source_unref(s);
+}
+
+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_cached();
+}
+
+static void source_io_unregister(sd_event_source *s) {
+ assert(s);
+ assert(s->type == SOURCE_IO);
+
+ if (event_pid_changed(s->event))
+ return;
+
+ if (!s->io.registered)
+ return;
+
+ if (epoll_ctl(s->event->epoll_fd, EPOLL_CTL_DEL, s->io.fd, NULL) < 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) {
+
+ assert(s);
+ assert(s->type == SOURCE_IO);
+ assert(enabled != SD_EVENT_OFF);
+
+ struct epoll_event ev = {
+ .events = events | (enabled == SD_EVENT_ONESHOT ? EPOLLONESHOT : 0),
+ .data.ptr = s,
+ };
+
+ if (epoll_ctl(s->event->epoll_fd,
+ s->io.registered ? EPOLL_CTL_MOD : EPOLL_CTL_ADD,
+ s->io.fd, &ev) < 0)
+ return -errno;
+
+ s->io.registered = true;
+
+ return 0;
+}
+
+static void source_child_pidfd_unregister(sd_event_source *s) {
+ assert(s);
+ assert(s->type == SOURCE_CHILD);
+
+ if (event_pid_changed(s->event))
+ return;
+
+ if (!s->child.registered)
+ return;
+
+ if (EVENT_SOURCE_WATCH_PIDFD(s))
+ if (epoll_ctl(s->event->epoll_fd, EPOLL_CTL_DEL, s->child.pidfd, NULL) < 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->child.registered = false;
+}
+
+static int source_child_pidfd_register(sd_event_source *s, int enabled) {
+ assert(s);
+ assert(s->type == SOURCE_CHILD);
+ assert(enabled != SD_EVENT_OFF);
+
+ if (EVENT_SOURCE_WATCH_PIDFD(s)) {
+ struct epoll_event ev = {
+ .events = EPOLLIN | (enabled == SD_EVENT_ONESHOT ? EPOLLONESHOT : 0),
+ .data.ptr = s,
+ };
+
+ if (epoll_ctl(s->event->epoll_fd,
+ s->child.registered ? EPOLL_CTL_MOD : EPOLL_CTL_ADD,
+ s->child.pidfd, &ev) < 0)
+ return -errno;
+ }
+
+ s->child.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 void event_free_signal_data(sd_event *e, struct signal_data *d) {
+ assert(e);
+
+ if (!d)
+ return;
+
+ hashmap_remove(e->signal_data, &d->priority);
+ safe_close(d->fd);
+ free(d);
+}
+
+static int event_make_signal_data(
+ sd_event *e,
+ int sig,
+ struct signal_data **ret) {
+
+ 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 = SD_EVENT_PRIORITY_NORMAL;
+
+ 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 = new(struct signal_data, 1);
+ if (!d)
+ return -ENOMEM;
+
+ *d = (struct signal_data) {
+ .wakeup = WAKEUP_SIGNAL_DATA,
+ .fd = -1,
+ .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 = fd_move_above_stdio(r);
+
+ struct epoll_event ev = {
+ .events = EPOLLIN,
+ .data.ptr = d,
+ };
+
+ if (epoll_ctl(e->epoll_fd, EPOLL_CTL_ADD, d->fd, &ev) < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ if (ret)
+ *ret = d;
+
+ return 0;
+
+fail:
+ if (added)
+ event_free_signal_data(e, 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 */
+ event_free_signal_data(e, 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 event_source_pp_prioq_reshuffle(sd_event_source *s) {
+ assert(s);
+
+ /* Reshuffles the pending + prepare prioqs. Called whenever the dispatch order changes, i.e. when
+ * they are enabled/disabled or marked pending and such. */
+
+ if (s->pending)
+ prioq_reshuffle(s->event->pending, s, &s->pending_index);
+
+ if (s->prepare)
+ prioq_reshuffle(s->event->prepare, s, &s->prepare_index);
+}
+
+static void event_source_time_prioq_reshuffle(sd_event_source *s) {
+ struct clock_data *d;
+
+ assert(s);
+ assert(EVENT_SOURCE_IS_TIME(s->type));
+
+ /* Called whenever the event source's timer ordering properties changed, i.e. time, accuracy,
+ * pending, enable state. Makes sure the two prioq's are ordered properly again. */
+ assert_se(d = event_get_clock_data(s->event, s->type));
+ prioq_reshuffle(d->earliest, s, &s->time.earliest_index);
+ prioq_reshuffle(d->latest, s, &s->time.latest_index);
+ d->needs_rearm = true;
+}
+
+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));
+ }
+
+ if (EVENT_SOURCE_WATCH_PIDFD(s))
+ source_child_pidfd_unregister(s);
+ else
+ 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;
+
+ case SOURCE_INOTIFY: {
+ struct inode_data *inode_data;
+
+ inode_data = s->inotify.inode_data;
+ if (inode_data) {
+ struct inotify_data *inotify_data;
+ assert_se(inotify_data = inode_data->inotify_data);
+
+ /* Detach this event source from the inode object */
+ LIST_REMOVE(inotify.by_inode_data, inode_data->event_sources, s);
+ s->inotify.inode_data = NULL;
+
+ if (s->pending) {
+ assert(inotify_data->n_pending > 0);
+ inotify_data->n_pending--;
+ }
+
+ /* Note that we don't reduce the inotify mask for the watch descriptor here if the inode is
+ * continued to being watched. That's because inotify doesn't really have an API for that: we
+ * can only change watch masks with access to the original inode either by fd or by path. But
+ * paths aren't stable, and keeping an O_PATH fd open all the time would mean wasting an fd
+ * continuously and keeping the mount busy which we can't really do. We could reconstruct the
+ * original inode from /proc/self/fdinfo/$INOTIFY_FD (as all watch descriptors are listed
+ * there), but given the need for open_by_handle_at() which is privileged and not universally
+ * available this would be quite an incomplete solution. Hence we go the other way, leave the
+ * mask set, even if it is not minimized now, and ignore all events we aren't interested in
+ * anymore after reception. Yes, this sucks, but … Linux … */
+
+ /* Maybe release the inode data (and its inotify) */
+ event_gc_inode_data(s->event, inode_data);
+ }
+
+ 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 = TAKE_PTR(s->event);
+ LIST_REMOVE(sources, event->sources, s);
+ event->n_sources--;
+
+ /* Note that we don't invalidate the type here, since we still need it in order to close the fd or
+ * pidfd associated with this event source, which we'll do only on source_free(). */
+
+ if (!s->floating)
+ sd_event_unref(event);
+}
+
+static void source_free(sd_event_source *s) {
+ assert(s);
+
+ source_disconnect(s);
+
+ if (s->type == SOURCE_IO && s->io.owned)
+ s->io.fd = safe_close(s->io.fd);
+
+ if (s->type == SOURCE_CHILD) {
+ /* Eventually the kernel will do this automatically for us, but for now let's emulate this (unreliably) in userspace. */
+
+ if (s->child.process_owned) {
+
+ if (!s->child.exited) {
+ bool sent = false;
+
+ if (s->child.pidfd >= 0) {
+ if (pidfd_send_signal(s->child.pidfd, SIGKILL, NULL, 0) < 0) {
+ if (errno == ESRCH) /* Already dead */
+ sent = true;
+ else if (!ERRNO_IS_NOT_SUPPORTED(errno))
+ log_debug_errno(errno, "Failed to kill process " PID_FMT " via pidfd_send_signal(), re-trying via kill(): %m",
+ s->child.pid);
+ } else
+ sent = true;
+ }
+
+ if (!sent)
+ if (kill(s->child.pid, SIGKILL) < 0)
+ if (errno != ESRCH) /* Already dead */
+ log_debug_errno(errno, "Failed to kill process " PID_FMT " via kill(), ignoring: %m",
+ s->child.pid);
+ }
+
+ if (!s->child.waited) {
+ siginfo_t si = {};
+
+ /* Reap the child if we can */
+ (void) waitid(P_PID, s->child.pid, &si, WEXITED);
+ }
+ }
+
+ if (s->child.pidfd_owned)
+ s->child.pidfd = safe_close(s->child.pidfd);
+ }
+
+ if (s->destroy_callback)
+ s->destroy_callback(s->userdata);
+
+ free(s->description);
+ free(s);
+}
+DEFINE_TRIVIAL_CLEANUP_FUNC(sd_event_source*, source_free);
+
+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))
+ event_source_time_prioq_reshuffle(s);
+
+ 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;
+ }
+
+ if (s->type == SOURCE_INOTIFY) {
+
+ assert(s->inotify.inode_data);
+ assert(s->inotify.inode_data->inotify_data);
+
+ if (b)
+ s->inotify.inode_data->inotify_data->n_pending ++;
+ else {
+ assert(s->inotify.inode_data->inotify_data->n_pending > 0);
+ s->inotify.inode_data->inotify_data->n_pending --;
+ }
+ }
+
+ return 0;
+}
+
+static sd_event_source *source_new(sd_event *e, bool floating, EventSourceType type) {
+ sd_event_source *s;
+
+ assert(e);
+
+ s = new(sd_event_source, 1);
+ if (!s)
+ return NULL;
+
+ *s = (struct sd_event_source) {
+ .n_ref = 1,
+ .event = e,
+ .floating = floating,
+ .type = type,
+ .pending_index = PRIOQ_IDX_NULL,
+ .prepare_index = PRIOQ_IDX_NULL,
+ };
+
+ if (!floating)
+ sd_event_ref(e);
+
+ LIST_PREPEND(sources, e->sources, s);
+ e->n_sources++;
+
+ return s;
+}
+
+static int io_exit_callback(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
+ assert(s);
+
+ return sd_event_exit(sd_event_source_get_event(s), PTR_TO_INT(userdata));
+}
+
+_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) {
+
+ _cleanup_(source_freep) sd_event_source *s = NULL;
+ int r;
+
+ assert_return(e, -EINVAL);
+ assert_return(e = event_resolve(e), -ENOPKG);
+ assert_return(fd >= 0, -EBADF);
+ assert_return(!(events & ~(EPOLLIN|EPOLLOUT|EPOLLRDHUP|EPOLLPRI|EPOLLERR|EPOLLHUP|EPOLLET)), -EINVAL);
+ assert_return(e->state != SD_EVENT_FINISHED, -ESTALE);
+ assert_return(!event_pid_changed(e), -ECHILD);
+
+ if (!callback)
+ callback = io_exit_callback;
+
+ 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)
+ return r;
+
+ if (ret)
+ *ret = s;
+ TAKE_PTR(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 within 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) {
+
+ assert(e);
+ assert(d);
+
+ if (_likely_(d->fd >= 0))
+ return 0;
+
+ _cleanup_close_ int fd = -1;
+
+ fd = timerfd_create(clock, TFD_NONBLOCK|TFD_CLOEXEC);
+ if (fd < 0)
+ return -errno;
+
+ fd = fd_move_above_stdio(fd);
+
+ struct epoll_event ev = {
+ .events = EPOLLIN,
+ .data.ptr = d,
+ };
+
+ if (epoll_ctl(e->epoll_fd, EPOLL_CTL_ADD, fd, &ev) < 0)
+ return -errno;
+
+ d->fd = TAKE_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;
+ _cleanup_(source_freep) sd_event_source *s = NULL;
+ struct clock_data *d;
+ int r;
+
+ assert_return(e, -EINVAL);
+ assert_return(e = event_resolve(e), -ENOPKG);
+ assert_return(accuracy != (uint64_t) -1, -EINVAL);
+ assert_return(e->state != SD_EVENT_FINISHED, -ESTALE);
+ assert_return(!event_pid_changed(e), -ECHILD);
+
+ if (!clock_supported(clock)) /* Checks whether the kernel supports the clock */
+ return -EOPNOTSUPP;
+
+ type = clock_to_event_source_type(clock); /* checks whether sd-event supports this clock */
+ if (type < 0)
+ return -EOPNOTSUPP;
+
+ if (!callback)
+ callback = time_exit_callback;
+
+ 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)
+ return r;
+
+ r = prioq_put(d->latest, s, &s->time.latest_index);
+ if (r < 0)
+ return r;
+
+ if (ret)
+ *ret = s;
+ TAKE_PTR(s);
+
+ return 0;
+}
+
+_public_ int sd_event_add_time_relative(
+ sd_event *e,
+ sd_event_source **ret,
+ clockid_t clock,
+ uint64_t usec,
+ uint64_t accuracy,
+ sd_event_time_handler_t callback,
+ void *userdata) {
+
+ usec_t t;
+ int r;
+
+ /* Same as sd_event_add_time() but operates relative to the event loop's current point in time, and
+ * checks for overflow. */
+
+ r = sd_event_now(e, clock, &t);
+ if (r < 0)
+ return r;
+
+ if (usec >= USEC_INFINITY - t)
+ return -EOVERFLOW;
+
+ return sd_event_add_time(e, ret, clock, t + usec, accuracy, callback, userdata);
+}
+
+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) {
+
+ _cleanup_(source_freep) sd_event_source *s = NULL;
+ struct signal_data *d;
+ int r;
+
+ assert_return(e, -EINVAL);
+ assert_return(e = event_resolve(e), -ENOPKG);
+ 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 = signal_is_blocked(sig);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ 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)
+ 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;
+ TAKE_PTR(s);
+
+ return 0;
+}
+
+static int child_exit_callback(sd_event_source *s, const siginfo_t *si, void *userdata) {
+ assert(s);
+
+ return sd_event_exit(sd_event_source_get_event(s), PTR_TO_INT(userdata));
+}
+
+static bool shall_use_pidfd(void) {
+ /* Mostly relevant for debugging, i.e. this is used in test-event.c to test the event loop once with and once without pidfd */
+ return getenv_bool_secure("SYSTEMD_PIDFD") != 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) {
+
+ _cleanup_(source_freep) sd_event_source *s = NULL;
+ int r;
+
+ assert_return(e, -EINVAL);
+ assert_return(e = event_resolve(e), -ENOPKG);
+ assert_return(pid > 1, -EINVAL);
+ assert_return(!(options & ~(WEXITED|WSTOPPED|WCONTINUED)), -EINVAL);
+ assert_return(options != 0, -EINVAL);
+ assert_return(e->state != SD_EVENT_FINISHED, -ESTALE);
+ assert_return(!event_pid_changed(e), -ECHILD);
+
+ if (!callback)
+ callback = child_exit_callback;
+
+ if (e->n_enabled_child_sources == 0) {
+ /* Caller must block SIGCHLD before using us to watch children, even if pidfd is available,
+ * for compatibility with pre-pidfd and because we don't want the reap the child processes
+ * ourselves, i.e. call waitid(), and don't want Linux' default internal logic for that to
+ * take effect.
+ *
+ * (As an optimization we only do this check on the first child event source created.) */
+ r = signal_is_blocked(SIGCHLD);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return -EBUSY;
+ }
+
+ 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->wakeup = WAKEUP_EVENT_SOURCE;
+ s->child.pid = pid;
+ s->child.options = options;
+ s->child.callback = callback;
+ s->userdata = userdata;
+ s->enabled = SD_EVENT_ONESHOT;
+
+ /* We always take a pidfd here if we can, even if we wait for anything else than WEXITED, so that we
+ * pin the PID, and make regular waitid() handling race-free. */
+
+ if (shall_use_pidfd()) {
+ s->child.pidfd = pidfd_open(s->child.pid, 0);
+ if (s->child.pidfd < 0) {
+ /* Propagate errors unless the syscall is not supported or blocked */
+ if (!ERRNO_IS_NOT_SUPPORTED(errno) && !ERRNO_IS_PRIVILEGE(errno))
+ return -errno;
+ } else
+ s->child.pidfd_owned = true; /* If we allocate the pidfd we own it by default */
+ } else
+ s->child.pidfd = -1;
+
+ r = hashmap_put(e->child_sources, PID_TO_PTR(pid), s);
+ if (r < 0)
+ return r;
+
+ if (EVENT_SOURCE_WATCH_PIDFD(s)) {
+ /* We have a pidfd and we only want to watch for exit */
+ r = source_child_pidfd_register(s, s->enabled);
+ if (r < 0)
+ return r;
+
+ } else {
+ /* We have no pidfd or we shall wait for some other event than WEXITED */
+ r = event_make_signal_data(e, SIGCHLD, NULL);
+ if (r < 0)
+ return r;
+
+ e->need_process_child = true;
+ }
+
+ e->n_enabled_child_sources++;
+
+ if (ret)
+ *ret = s;
+ TAKE_PTR(s);
+ return 0;
+}
+
+_public_ int sd_event_add_child_pidfd(
+ sd_event *e,
+ sd_event_source **ret,
+ int pidfd,
+ int options,
+ sd_event_child_handler_t callback,
+ void *userdata) {
+
+
+ _cleanup_(source_freep) sd_event_source *s = NULL;
+ pid_t pid;
+ int r;
+
+ assert_return(e, -EINVAL);
+ assert_return(e = event_resolve(e), -ENOPKG);
+ assert_return(pidfd >= 0, -EBADF);
+ assert_return(!(options & ~(WEXITED|WSTOPPED|WCONTINUED)), -EINVAL);
+ assert_return(options != 0, -EINVAL);
+ assert_return(e->state != SD_EVENT_FINISHED, -ESTALE);
+ assert_return(!event_pid_changed(e), -ECHILD);
+
+ if (!callback)
+ callback = child_exit_callback;
+
+ if (e->n_enabled_child_sources == 0) {
+ r = signal_is_blocked(SIGCHLD);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return -EBUSY;
+ }
+
+ r = hashmap_ensure_allocated(&e->child_sources, NULL);
+ if (r < 0)
+ return r;
+
+ r = pidfd_get_pid(pidfd, &pid);
+ 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->wakeup = WAKEUP_EVENT_SOURCE;
+ s->child.pidfd = pidfd;
+ s->child.pid = pid;
+ s->child.options = options;
+ s->child.callback = callback;
+ s->child.pidfd_owned = false; /* If we got the pidfd passed in we don't own it by default (similar to the IO fd case) */
+ s->userdata = userdata;
+ s->enabled = SD_EVENT_ONESHOT;
+
+ r = hashmap_put(e->child_sources, PID_TO_PTR(pid), s);
+ if (r < 0)
+ return r;
+
+ if (EVENT_SOURCE_WATCH_PIDFD(s)) {
+ /* We only want to watch for WEXITED */
+ r = source_child_pidfd_register(s, s->enabled);
+ if (r < 0)
+ return r;
+ } else {
+ /* We shall wait for some other event than WEXITED */
+ r = event_make_signal_data(e, SIGCHLD, NULL);
+ if (r < 0)
+ return r;
+
+ e->need_process_child = true;
+ }
+
+ e->n_enabled_child_sources++;
+
+ if (ret)
+ *ret = s;
+ TAKE_PTR(s);
+ return 0;
+}
+
+static int generic_exit_callback(sd_event_source *s, void *userdata) {
+ assert(s);
+
+ return sd_event_exit(sd_event_source_get_event(s), PTR_TO_INT(userdata));
+}
+
+_public_ int sd_event_add_defer(
+ sd_event *e,
+ sd_event_source **ret,
+ sd_event_handler_t callback,
+ void *userdata) {
+
+ _cleanup_(source_freep) sd_event_source *s = NULL;
+ int r;
+
+ assert_return(e, -EINVAL);
+ assert_return(e = event_resolve(e), -ENOPKG);
+ assert_return(e->state != SD_EVENT_FINISHED, -ESTALE);
+ assert_return(!event_pid_changed(e), -ECHILD);
+
+ if (!callback)
+ callback = generic_exit_callback;
+
+ 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)
+ return r;
+
+ if (ret)
+ *ret = s;
+ TAKE_PTR(s);
+
+ return 0;
+}
+
+_public_ int sd_event_add_post(
+ sd_event *e,
+ sd_event_source **ret,
+ sd_event_handler_t callback,
+ void *userdata) {
+
+ _cleanup_(source_freep) sd_event_source *s = NULL;
+ int r;
+
+ assert_return(e, -EINVAL);
+ assert_return(e = event_resolve(e), -ENOPKG);
+ assert_return(e->state != SD_EVENT_FINISHED, -ESTALE);
+ assert_return(!event_pid_changed(e), -ECHILD);
+
+ if (!callback)
+ callback = generic_exit_callback;
+
+ 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_ensure_put(&e->post_sources, NULL, s);
+ if (r < 0)
+ return r;
+ assert(r > 0);
+
+ if (ret)
+ *ret = s;
+ TAKE_PTR(s);
+
+ return 0;
+}
+
+_public_ int sd_event_add_exit(
+ sd_event *e,
+ sd_event_source **ret,
+ sd_event_handler_t callback,
+ void *userdata) {
+
+ _cleanup_(source_freep) sd_event_source *s = NULL;
+ int r;
+
+ assert_return(e, -EINVAL);
+ assert_return(e = event_resolve(e), -ENOPKG);
+ 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)
+ return r;
+
+ if (ret)
+ *ret = s;
+ TAKE_PTR(s);
+
+ return 0;
+}
+
+static void event_free_inotify_data(sd_event *e, struct inotify_data *d) {
+ assert(e);
+
+ if (!d)
+ return;
+
+ assert(hashmap_isempty(d->inodes));
+ assert(hashmap_isempty(d->wd));
+
+ if (d->buffer_filled > 0)
+ LIST_REMOVE(buffered, e->inotify_data_buffered, d);
+
+ hashmap_free(d->inodes);
+ hashmap_free(d->wd);
+
+ assert_se(hashmap_remove(e->inotify_data, &d->priority) == d);
+
+ if (d->fd >= 0) {
+ if (epoll_ctl(e->epoll_fd, EPOLL_CTL_DEL, d->fd, NULL) < 0)
+ log_debug_errno(errno, "Failed to remove inotify fd from epoll, ignoring: %m");
+
+ safe_close(d->fd);
+ }
+ free(d);
+}
+
+static int event_make_inotify_data(
+ sd_event *e,
+ int64_t priority,
+ struct inotify_data **ret) {
+
+ _cleanup_close_ int fd = -1;
+ struct inotify_data *d;
+ int r;
+
+ assert(e);
+
+ d = hashmap_get(e->inotify_data, &priority);
+ if (d) {
+ if (ret)
+ *ret = d;
+ return 0;
+ }
+
+ fd = inotify_init1(IN_NONBLOCK|O_CLOEXEC);
+ if (fd < 0)
+ return -errno;
+
+ fd = fd_move_above_stdio(fd);
+
+ r = hashmap_ensure_allocated(&e->inotify_data, &uint64_hash_ops);
+ if (r < 0)
+ return r;
+
+ d = new(struct inotify_data, 1);
+ if (!d)
+ return -ENOMEM;
+
+ *d = (struct inotify_data) {
+ .wakeup = WAKEUP_INOTIFY_DATA,
+ .fd = TAKE_FD(fd),
+ .priority = priority,
+ };
+
+ r = hashmap_put(e->inotify_data, &d->priority, d);
+ if (r < 0) {
+ d->fd = safe_close(d->fd);
+ free(d);
+ return r;
+ }
+
+ struct epoll_event ev = {
+ .events = EPOLLIN,
+ .data.ptr = d,
+ };
+
+ if (epoll_ctl(e->epoll_fd, EPOLL_CTL_ADD, d->fd, &ev) < 0) {
+ r = -errno;
+ d->fd = safe_close(d->fd); /* let's close this ourselves, as event_free_inotify_data() would otherwise
+ * remove the fd from the epoll first, which we don't want as we couldn't
+ * add it in the first place. */
+ event_free_inotify_data(e, d);
+ return r;
+ }
+
+ if (ret)
+ *ret = d;
+
+ return 1;
+}
+
+static int inode_data_compare(const struct inode_data *x, const struct inode_data *y) {
+ int r;
+
+ assert(x);
+ assert(y);
+
+ r = CMP(x->dev, y->dev);
+ if (r != 0)
+ return r;
+
+ return CMP(x->ino, y->ino);
+}
+
+static void inode_data_hash_func(const struct inode_data *d, struct siphash *state) {
+ assert(d);
+
+ siphash24_compress(&d->dev, sizeof(d->dev), state);
+ siphash24_compress(&d->ino, sizeof(d->ino), state);
+}
+
+DEFINE_PRIVATE_HASH_OPS(inode_data_hash_ops, struct inode_data, inode_data_hash_func, inode_data_compare);
+
+static void event_free_inode_data(
+ sd_event *e,
+ struct inode_data *d) {
+
+ assert(e);
+
+ if (!d)
+ return;
+
+ assert(!d->event_sources);
+
+ if (d->fd >= 0) {
+ LIST_REMOVE(to_close, e->inode_data_to_close, d);
+ safe_close(d->fd);
+ }
+
+ if (d->inotify_data) {
+
+ if (d->wd >= 0) {
+ if (d->inotify_data->fd >= 0) {
+ /* So here's a problem. At the time this runs the watch descriptor might already be
+ * invalidated, because an IN_IGNORED event might be queued right the moment we enter
+ * the syscall. Hence, whenever we get EINVAL, ignore it entirely, since it's a very
+ * likely case to happen. */
+
+ if (inotify_rm_watch(d->inotify_data->fd, d->wd) < 0 && errno != EINVAL)
+ log_debug_errno(errno, "Failed to remove watch descriptor %i from inotify, ignoring: %m", d->wd);
+ }
+
+ assert_se(hashmap_remove(d->inotify_data->wd, INT_TO_PTR(d->wd)) == d);
+ }
+
+ assert_se(hashmap_remove(d->inotify_data->inodes, d) == d);
+ }
+
+ free(d);
+}
+
+static void event_gc_inode_data(
+ sd_event *e,
+ struct inode_data *d) {
+
+ struct inotify_data *inotify_data;
+
+ assert(e);
+
+ if (!d)
+ return;
+
+ if (d->event_sources)
+ return;
+
+ inotify_data = d->inotify_data;
+ event_free_inode_data(e, d);
+
+ if (inotify_data && hashmap_isempty(inotify_data->inodes))
+ event_free_inotify_data(e, inotify_data);
+}
+
+static int event_make_inode_data(
+ sd_event *e,
+ struct inotify_data *inotify_data,
+ dev_t dev,
+ ino_t ino,
+ struct inode_data **ret) {
+
+ struct inode_data *d, key;
+ int r;
+
+ assert(e);
+ assert(inotify_data);
+
+ key = (struct inode_data) {
+ .ino = ino,
+ .dev = dev,
+ };
+
+ d = hashmap_get(inotify_data->inodes, &key);
+ if (d) {
+ if (ret)
+ *ret = d;
+
+ return 0;
+ }
+
+ r = hashmap_ensure_allocated(&inotify_data->inodes, &inode_data_hash_ops);
+ if (r < 0)
+ return r;
+
+ d = new(struct inode_data, 1);
+ if (!d)
+ return -ENOMEM;
+
+ *d = (struct inode_data) {
+ .dev = dev,
+ .ino = ino,
+ .wd = -1,
+ .fd = -1,
+ .inotify_data = inotify_data,
+ };
+
+ r = hashmap_put(inotify_data->inodes, d, d);
+ if (r < 0) {
+ free(d);
+ return r;
+ }
+
+ if (ret)
+ *ret = d;
+
+ return 1;
+}
+
+static uint32_t inode_data_determine_mask(struct inode_data *d) {
+ bool excl_unlink = true;
+ uint32_t combined = 0;
+ sd_event_source *s;
+
+ assert(d);
+
+ /* Combines the watch masks of all event sources watching this inode. We generally just OR them together, but
+ * the IN_EXCL_UNLINK flag is ANDed instead.
+ *
+ * Note that we add all sources to the mask here, regardless whether enabled, disabled or oneshot. That's
+ * because we cannot change the mask anymore after the event source was created once, since the kernel has no
+ * API for that. Hence we need to subscribe to the maximum mask we ever might be interested in, and suppress
+ * events we don't care for client-side. */
+
+ LIST_FOREACH(inotify.by_inode_data, s, d->event_sources) {
+
+ if ((s->inotify.mask & IN_EXCL_UNLINK) == 0)
+ excl_unlink = false;
+
+ combined |= s->inotify.mask;
+ }
+
+ return (combined & ~(IN_ONESHOT|IN_DONT_FOLLOW|IN_ONLYDIR|IN_EXCL_UNLINK)) | (excl_unlink ? IN_EXCL_UNLINK : 0);
+}
+
+static int inode_data_realize_watch(sd_event *e, struct inode_data *d) {
+ uint32_t combined_mask;
+ int wd, r;
+
+ assert(d);
+ assert(d->fd >= 0);
+
+ combined_mask = inode_data_determine_mask(d);
+
+ if (d->wd >= 0 && combined_mask == d->combined_mask)
+ return 0;
+
+ r = hashmap_ensure_allocated(&d->inotify_data->wd, NULL);
+ if (r < 0)
+ return r;
+
+ wd = inotify_add_watch_fd(d->inotify_data->fd, d->fd, combined_mask);
+ if (wd < 0)
+ return -errno;
+
+ if (d->wd < 0) {
+ r = hashmap_put(d->inotify_data->wd, INT_TO_PTR(wd), d);
+ if (r < 0) {
+ (void) inotify_rm_watch(d->inotify_data->fd, wd);
+ return r;
+ }
+
+ d->wd = wd;
+
+ } else if (d->wd != wd) {
+
+ log_debug("Weird, the watch descriptor we already knew for this inode changed?");
+ (void) inotify_rm_watch(d->fd, wd);
+ return -EINVAL;
+ }
+
+ d->combined_mask = combined_mask;
+ return 1;
+}
+
+static int inotify_exit_callback(sd_event_source *s, const struct inotify_event *event, void *userdata) {
+ assert(s);
+
+ return sd_event_exit(sd_event_source_get_event(s), PTR_TO_INT(userdata));
+}
+
+_public_ int sd_event_add_inotify(
+ sd_event *e,
+ sd_event_source **ret,
+ const char *path,
+ uint32_t mask,
+ sd_event_inotify_handler_t callback,
+ void *userdata) {
+
+ struct inotify_data *inotify_data = NULL;
+ struct inode_data *inode_data = NULL;
+ _cleanup_close_ int fd = -1;
+ _cleanup_(source_freep) sd_event_source *s = NULL;
+ struct stat st;
+ int r;
+
+ assert_return(e, -EINVAL);
+ assert_return(e = event_resolve(e), -ENOPKG);
+ assert_return(path, -EINVAL);
+ assert_return(e->state != SD_EVENT_FINISHED, -ESTALE);
+ assert_return(!event_pid_changed(e), -ECHILD);
+
+ if (!callback)
+ callback = inotify_exit_callback;
+
+ /* Refuse IN_MASK_ADD since we coalesce watches on the same inode, and hence really don't want to merge
+ * masks. Or in other words, this whole code exists only to manage IN_MASK_ADD type operations for you, hence
+ * the user can't use them for us. */
+ if (mask & IN_MASK_ADD)
+ return -EINVAL;
+
+ fd = open(path, O_PATH|O_CLOEXEC|
+ (mask & IN_ONLYDIR ? O_DIRECTORY : 0)|
+ (mask & IN_DONT_FOLLOW ? O_NOFOLLOW : 0));
+ if (fd < 0)
+ return -errno;
+
+ if (fstat(fd, &st) < 0)
+ return -errno;
+
+ s = source_new(e, !ret, SOURCE_INOTIFY);
+ if (!s)
+ return -ENOMEM;
+
+ s->enabled = mask & IN_ONESHOT ? SD_EVENT_ONESHOT : SD_EVENT_ON;
+ s->inotify.mask = mask;
+ s->inotify.callback = callback;
+ s->userdata = userdata;
+
+ /* Allocate an inotify object for this priority, and an inode object within it */
+ r = event_make_inotify_data(e, SD_EVENT_PRIORITY_NORMAL, &inotify_data);
+ if (r < 0)
+ return r;
+
+ r = event_make_inode_data(e, inotify_data, st.st_dev, st.st_ino, &inode_data);
+ if (r < 0) {
+ event_free_inotify_data(e, inotify_data);
+ return r;
+ }
+
+ /* Keep the O_PATH fd around until the first iteration of the loop, so that we can still change the priority of
+ * the event source, until then, for which we need the original inode. */
+ if (inode_data->fd < 0) {
+ inode_data->fd = TAKE_FD(fd);
+ LIST_PREPEND(to_close, e->inode_data_to_close, inode_data);
+ }
+
+ /* Link our event source to the inode data object */
+ LIST_PREPEND(inotify.by_inode_data, inode_data->event_sources, s);
+ s->inotify.inode_data = inode_data;
+
+ /* Actually realize the watch now */
+ r = inode_data_realize_watch(e, inode_data);
+ if (r < 0)
+ return r;
+
+ (void) sd_event_source_set_description(s, path);
+
+ if (ret)
+ *ret = s;
+ TAKE_PTR(s);
+
+ return 0;
+}
+
+static sd_event_source* event_source_free(sd_event_source *s) {
+ if (!s)
+ return NULL;
+
+ /* 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;
+}
+
+DEFINE_PUBLIC_TRIVIAL_REF_UNREF_FUNC(sd_event_source, sd_event_source, event_source_free);
+
+_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(!event_pid_changed(s->event), -ECHILD);
+
+ if (!s->description)
+ return -ENXIO;
+
+ *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;
+ }
+
+ (void) epoll_ctl(s->event->epoll_fd, EPOLL_CTL_DEL, saved_fd, NULL);
+ }
+
+ return 0;
+}
+
+_public_ int sd_event_source_get_io_fd_own(sd_event_source *s) {
+ assert_return(s, -EINVAL);
+ assert_return(s->type == SOURCE_IO, -EDOM);
+
+ return s->io.owned;
+}
+
+_public_ int sd_event_source_set_io_fd_own(sd_event_source *s, int own) {
+ assert_return(s, -EINVAL);
+ assert_return(s->type == SOURCE_IO, -EDOM);
+
+ s->io.owned = own;
+ 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;
+
+ r = source_set_pending(s, false);
+ if (r < 0)
+ return r;
+
+ if (s->enabled != SD_EVENT_OFF) {
+ r = source_io_register(s, s->enabled, events);
+ if (r < 0)
+ return r;
+ }
+
+ s->io.events = events;
+
+ 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);
+
+ *priority = s->priority;
+ return 0;
+}
+
+_public_ int sd_event_source_set_priority(sd_event_source *s, int64_t priority) {
+ bool rm_inotify = false, rm_inode = false;
+ struct inotify_data *new_inotify_data = NULL;
+ struct inode_data *new_inode_data = NULL;
+ 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_INOTIFY) {
+ struct inode_data *old_inode_data;
+
+ assert(s->inotify.inode_data);
+ old_inode_data = s->inotify.inode_data;
+
+ /* We need the original fd to change the priority. If we don't have it we can't change the priority,
+ * anymore. Note that we close any fds when entering the next event loop iteration, i.e. for inotify
+ * events we allow priority changes only until the first following iteration. */
+ if (old_inode_data->fd < 0)
+ return -EOPNOTSUPP;
+
+ r = event_make_inotify_data(s->event, priority, &new_inotify_data);
+ if (r < 0)
+ return r;
+ rm_inotify = r > 0;
+
+ r = event_make_inode_data(s->event, new_inotify_data, old_inode_data->dev, old_inode_data->ino, &new_inode_data);
+ if (r < 0)
+ goto fail;
+ rm_inode = r > 0;
+
+ if (new_inode_data->fd < 0) {
+ /* Duplicate the fd for the new inode object if we don't have any yet */
+ new_inode_data->fd = fcntl(old_inode_data->fd, F_DUPFD_CLOEXEC, 3);
+ if (new_inode_data->fd < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ LIST_PREPEND(to_close, s->event->inode_data_to_close, new_inode_data);
+ }
+
+ /* Move the event source to the new inode data structure */
+ LIST_REMOVE(inotify.by_inode_data, old_inode_data->event_sources, s);
+ LIST_PREPEND(inotify.by_inode_data, new_inode_data->event_sources, s);
+ s->inotify.inode_data = new_inode_data;
+
+ /* Now create the new watch */
+ r = inode_data_realize_watch(s->event, new_inode_data);
+ if (r < 0) {
+ /* Move it back */
+ LIST_REMOVE(inotify.by_inode_data, new_inode_data->event_sources, s);
+ LIST_PREPEND(inotify.by_inode_data, old_inode_data->event_sources, s);
+ s->inotify.inode_data = old_inode_data;
+ goto fail;
+ }
+
+ s->priority = priority;
+
+ event_gc_inode_data(s->event, old_inode_data);
+
+ } else 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;
+
+ event_source_pp_prioq_reshuffle(s);
+
+ if (s->type == SOURCE_EXIT)
+ prioq_reshuffle(s->event->exit, s, &s->exit.prioq_index);
+
+ return 0;
+
+fail:
+ if (rm_inode)
+ event_free_inode_data(s->event, new_inode_data);
+
+ if (rm_inotify)
+ event_free_inotify_data(s->event, new_inotify_data);
+
+ return r;
+}
+
+_public_ int sd_event_source_get_enabled(sd_event_source *s, int *m) {
+ assert_return(s, -EINVAL);
+ assert_return(!event_pid_changed(s->event), -ECHILD);
+
+ if (m)
+ *m = s->enabled;
+ return s->enabled != SD_EVENT_OFF;
+}
+
+static int event_source_disable(sd_event_source *s) {
+ int r;
+
+ assert(s);
+ assert(s->enabled != SD_EVENT_OFF);
+
+ /* Unset the pending flag when this event source is disabled */
+ if (!IN_SET(s->type, SOURCE_DEFER, SOURCE_EXIT)) {
+ r = source_set_pending(s, false);
+ if (r < 0)
+ return r;
+ }
+
+ s->enabled = SD_EVENT_OFF;
+
+ switch (s->type) {
+
+ case SOURCE_IO:
+ 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:
+ event_source_time_prioq_reshuffle(s);
+ break;
+
+ case SOURCE_SIGNAL:
+ event_gc_signal_data(s->event, &s->priority, s->signal.sig);
+ break;
+
+ case SOURCE_CHILD:
+ assert(s->event->n_enabled_child_sources > 0);
+ s->event->n_enabled_child_sources--;
+
+ if (EVENT_SOURCE_WATCH_PIDFD(s))
+ source_child_pidfd_unregister(s);
+ else
+ event_gc_signal_data(s->event, &s->priority, SIGCHLD);
+ break;
+
+ case SOURCE_EXIT:
+ prioq_reshuffle(s->event->exit, s, &s->exit.prioq_index);
+ break;
+
+ case SOURCE_DEFER:
+ case SOURCE_POST:
+ case SOURCE_INOTIFY:
+ break;
+
+ default:
+ assert_not_reached("Wut? I shouldn't exist.");
+ }
+
+ return 0;
+}
+
+static int event_source_enable(sd_event_source *s, int enable) {
+ int r;
+
+ assert(s);
+ assert(IN_SET(enable, SD_EVENT_ON, SD_EVENT_ONESHOT));
+ assert(s->enabled == SD_EVENT_OFF);
+
+ /* Unset the pending flag when this event source is enabled */
+ if (!IN_SET(s->type, SOURCE_DEFER, SOURCE_EXIT)) {
+ r = source_set_pending(s, false);
+ if (r < 0)
+ return r;
+ }
+
+ switch (s->type) {
+ case SOURCE_IO:
+ r = source_io_register(s, enable, s->io.events);
+ if (r < 0)
+ return r;
+ break;
+
+ case SOURCE_SIGNAL:
+ r = event_make_signal_data(s->event, s->signal.sig, NULL);
+ if (r < 0) {
+ event_gc_signal_data(s->event, &s->priority, s->signal.sig);
+ return r;
+ }
+
+ break;
+
+ case SOURCE_CHILD:
+ if (EVENT_SOURCE_WATCH_PIDFD(s)) {
+ /* yes, we have pidfd */
+
+ r = source_child_pidfd_register(s, enable);
+ if (r < 0)
+ return r;
+ } else {
+ /* no pidfd, or something other to watch for than WEXITED */
+
+ r = event_make_signal_data(s->event, SIGCHLD, NULL);
+ if (r < 0) {
+ event_gc_signal_data(s->event, &s->priority, SIGCHLD);
+ return r;
+ }
+ }
+
+ s->event->n_enabled_child_sources++;
+
+ break;
+
+ case SOURCE_TIME_REALTIME:
+ case SOURCE_TIME_BOOTTIME:
+ case SOURCE_TIME_MONOTONIC:
+ case SOURCE_TIME_REALTIME_ALARM:
+ case SOURCE_TIME_BOOTTIME_ALARM:
+ case SOURCE_EXIT:
+ case SOURCE_DEFER:
+ case SOURCE_POST:
+ case SOURCE_INOTIFY:
+ break;
+
+ default:
+ assert_not_reached("Wut? I shouldn't exist.");
+ }
+
+ s->enabled = enable;
+
+ /* Non-failing operations below */
+ switch (s->type) {
+ case SOURCE_TIME_REALTIME:
+ case SOURCE_TIME_BOOTTIME:
+ case SOURCE_TIME_MONOTONIC:
+ case SOURCE_TIME_REALTIME_ALARM:
+ case SOURCE_TIME_BOOTTIME_ALARM:
+ event_source_time_prioq_reshuffle(s);
+ break;
+
+ case SOURCE_EXIT:
+ prioq_reshuffle(s->event->exit, s, &s->exit.prioq_index);
+ break;
+
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+_public_ int sd_event_source_set_enabled(sd_event_source *s, int m) {
+ int r;
+
+ assert_return(s, -EINVAL);
+ assert_return(IN_SET(m, SD_EVENT_OFF, SD_EVENT_ON, 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) /* No change? */
+ return 0;
+
+ if (m == SD_EVENT_OFF)
+ r = event_source_disable(s);
+ else {
+ if (s->enabled != SD_EVENT_OFF) {
+ /* Switching from "on" to "oneshot" or back? If that's the case, we can take a shortcut, the
+ * event source is already enabled after all. */
+ s->enabled = m;
+ return 0;
+ }
+
+ r = event_source_enable(s, m);
+ }
+ if (r < 0)
+ return r;
+
+ event_source_pp_prioq_reshuffle(s);
+ 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) {
+ int r;
+
+ 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);
+
+ r = source_set_pending(s, false);
+ if (r < 0)
+ return r;
+
+ s->time.next = usec;
+
+ event_source_time_prioq_reshuffle(s);
+ return 0;
+}
+
+_public_ int sd_event_source_set_time_relative(sd_event_source *s, uint64_t usec) {
+ usec_t t;
+ int r;
+
+ assert_return(s, -EINVAL);
+ assert_return(EVENT_SOURCE_IS_TIME(s->type), -EDOM);
+
+ r = sd_event_now(s->event, event_source_type_to_clock(s->type), &t);
+ if (r < 0)
+ return r;
+
+ if (usec >= USEC_INFINITY - t)
+ return -EOVERFLOW;
+
+ return sd_event_source_set_time(s, t + usec);
+}
+
+_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) {
+ int r;
+
+ 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);
+
+ r = source_set_pending(s, false);
+ if (r < 0)
+ return r;
+
+ if (usec == 0)
+ usec = DEFAULT_ACCURACY_USEC;
+
+ s->time.accuracy = usec;
+
+ event_source_time_prioq_reshuffle(s);
+ 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_get_child_pidfd(sd_event_source *s) {
+ assert_return(s, -EINVAL);
+ assert_return(s->type == SOURCE_CHILD, -EDOM);
+ assert_return(!event_pid_changed(s->event), -ECHILD);
+
+ if (s->child.pidfd < 0)
+ return -EOPNOTSUPP;
+
+ return s->child.pidfd;
+}
+
+_public_ int sd_event_source_send_child_signal(sd_event_source *s, int sig, const siginfo_t *si, unsigned flags) {
+ assert_return(s, -EINVAL);
+ assert_return(s->type == SOURCE_CHILD, -EDOM);
+ assert_return(!event_pid_changed(s->event), -ECHILD);
+ assert_return(SIGNAL_VALID(sig), -EINVAL);
+
+ /* If we already have seen indication the process exited refuse sending a signal early. This way we
+ * can be sure we don't accidentally kill the wrong process on PID reuse when pidfds are not
+ * available. */
+ if (s->child.exited)
+ return -ESRCH;
+
+ if (s->child.pidfd >= 0) {
+ siginfo_t copy;
+
+ /* pidfd_send_signal() changes the siginfo_t argument. This is weird, let's hence copy the
+ * structure here */
+ if (si)
+ copy = *si;
+
+ if (pidfd_send_signal(s->child.pidfd, sig, si ? &copy : NULL, 0) < 0) {
+ /* Let's propagate the error only if the system call is not implemented or prohibited */
+ if (!ERRNO_IS_NOT_SUPPORTED(errno) && !ERRNO_IS_PRIVILEGE(errno))
+ return -errno;
+ } else
+ return 0;
+ }
+
+ /* Flags are only supported for pidfd_send_signal(), not for rt_sigqueueinfo(), hence let's refuse
+ * this here. */
+ if (flags != 0)
+ return -EOPNOTSUPP;
+
+ if (si) {
+ /* We use rt_sigqueueinfo() only if siginfo_t is specified. */
+ siginfo_t copy = *si;
+
+ if (rt_sigqueueinfo(s->child.pid, sig, &copy) < 0)
+ return -errno;
+ } else if (kill(s->child.pid, sig) < 0)
+ return -errno;
+
+ return 0;
+}
+
+_public_ int sd_event_source_get_child_pidfd_own(sd_event_source *s) {
+ assert_return(s, -EINVAL);
+ assert_return(s->type == SOURCE_CHILD, -EDOM);
+
+ if (s->child.pidfd < 0)
+ return -EOPNOTSUPP;
+
+ return s->child.pidfd_owned;
+}
+
+_public_ int sd_event_source_set_child_pidfd_own(sd_event_source *s, int own) {
+ assert_return(s, -EINVAL);
+ assert_return(s->type == SOURCE_CHILD, -EDOM);
+
+ if (s->child.pidfd < 0)
+ return -EOPNOTSUPP;
+
+ s->child.pidfd_owned = own;
+ return 0;
+}
+
+_public_ int sd_event_source_get_child_process_own(sd_event_source *s) {
+ assert_return(s, -EINVAL);
+ assert_return(s->type == SOURCE_CHILD, -EDOM);
+
+ return s->child.process_owned;
+}
+
+_public_ int sd_event_source_set_child_process_own(sd_event_source *s, int own) {
+ assert_return(s, -EINVAL);
+ assert_return(s->type == SOURCE_CHILD, -EDOM);
+
+ s->child.process_owned = own;
+ return 0;
+}
+
+_public_ int sd_event_source_get_inotify_mask(sd_event_source *s, uint32_t *mask) {
+ assert_return(s, -EINVAL);
+ assert_return(mask, -EINVAL);
+ assert_return(s->type == SOURCE_INOTIFY, -EDOM);
+ assert_return(!event_pid_changed(s->event), -ECHILD);
+
+ *mask = s->inotify.mask;
+ 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;
+
+ 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 */
+ if (timerfd_settime(d->fd, TFD_TIMER_ABSTIME, &its, NULL) < 0)
+ return -errno;
+
+ 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);
+
+ if (timerfd_settime(d->fd, TFD_TIMER_ABSTIME, &its, NULL) < 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 (IN_SET(errno, EAGAIN, 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;
+
+ event_source_time_prioq_reshuffle(s);
+ }
+
+ return 0;
+}
+
+static int process_child(sd_event *e) {
+ sd_event_source *s;
+ 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) {
+ assert(s->type == SOURCE_CHILD);
+
+ if (s->pending)
+ continue;
+
+ if (s->enabled == SD_EVENT_OFF)
+ continue;
+
+ if (s->child.exited)
+ continue;
+
+ if (EVENT_SOURCE_WATCH_PIDFD(s)) /* There's a usable pidfd known for this event source? then don't waitid() for it here */
+ continue;
+
+ zero(s->child.siginfo);
+ if (waitid(P_PID, s->child.pid, &s->child.siginfo,
+ WNOHANG | (s->child.options & WEXITED ? WNOWAIT : 0) | s->child.options) < 0)
+ return -errno;
+
+ if (s->child.siginfo.si_pid != 0) {
+ bool zombie = IN_SET(s->child.siginfo.si_code, CLD_EXITED, CLD_KILLED, CLD_DUMPED);
+
+ if (zombie)
+ s->child.exited = true;
+
+ 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));
+ (void) 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_pidfd(sd_event *e, sd_event_source *s, uint32_t revents) {
+ assert(e);
+ assert(s);
+ assert(s->type == SOURCE_CHILD);
+
+ if (s->pending)
+ return 0;
+
+ if (s->enabled == SD_EVENT_OFF)
+ return 0;
+
+ if (!EVENT_SOURCE_WATCH_PIDFD(s))
+ return 0;
+
+ zero(s->child.siginfo);
+ if (waitid(P_PID, s->child.pid, &s->child.siginfo, WNOHANG | WNOWAIT | s->child.options) < 0)
+ return -errno;
+
+ if (s->child.siginfo.si_pid == 0)
+ return 0;
+
+ if (IN_SET(s->child.siginfo.si_code, CLD_EXITED, CLD_KILLED, CLD_DUMPED))
+ s->child.exited = true;
+
+ return source_set_pending(s, true);
+}
+
+static int process_signal(sd_event *e, struct signal_data *d, uint32_t events) {
+ bool read_one = false;
+ int r;
+
+ assert(e);
+ assert(d);
+ 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 (IN_SET(errno, EAGAIN, 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 event_inotify_data_read(sd_event *e, struct inotify_data *d, uint32_t revents) {
+ ssize_t n;
+
+ assert(e);
+ assert(d);
+
+ assert_return(revents == EPOLLIN, -EIO);
+
+ /* If there's already an event source pending for this priority, don't read another */
+ if (d->n_pending > 0)
+ return 0;
+
+ /* Is the read buffer non-empty? If so, let's not read more */
+ if (d->buffer_filled > 0)
+ return 0;
+
+ n = read(d->fd, &d->buffer, sizeof(d->buffer));
+ if (n < 0) {
+ if (IN_SET(errno, EAGAIN, EINTR))
+ return 0;
+
+ return -errno;
+ }
+
+ assert(n > 0);
+ d->buffer_filled = (size_t) n;
+ LIST_PREPEND(buffered, e->inotify_data_buffered, d);
+
+ return 1;
+}
+
+static void event_inotify_data_drop(sd_event *e, struct inotify_data *d, size_t sz) {
+ assert(e);
+ assert(d);
+ assert(sz <= d->buffer_filled);
+
+ if (sz == 0)
+ return;
+
+ /* Move the rest to the buffer to the front, in order to get things properly aligned again */
+ memmove(d->buffer.raw, d->buffer.raw + sz, d->buffer_filled - sz);
+ d->buffer_filled -= sz;
+
+ if (d->buffer_filled == 0)
+ LIST_REMOVE(buffered, e->inotify_data_buffered, d);
+}
+
+static int event_inotify_data_process(sd_event *e, struct inotify_data *d) {
+ int r;
+
+ assert(e);
+ assert(d);
+
+ /* If there's already an event source pending for this priority, don't read another */
+ if (d->n_pending > 0)
+ return 0;
+
+ while (d->buffer_filled > 0) {
+ size_t sz;
+
+ /* Let's validate that the event structures are complete */
+ if (d->buffer_filled < offsetof(struct inotify_event, name))
+ return -EIO;
+
+ sz = offsetof(struct inotify_event, name) + d->buffer.ev.len;
+ if (d->buffer_filled < sz)
+ return -EIO;
+
+ if (d->buffer.ev.mask & IN_Q_OVERFLOW) {
+ struct inode_data *inode_data;
+
+ /* The queue overran, let's pass this event to all event sources connected to this inotify
+ * object */
+
+ HASHMAP_FOREACH(inode_data, d->inodes) {
+ sd_event_source *s;
+
+ LIST_FOREACH(inotify.by_inode_data, s, inode_data->event_sources) {
+
+ if (s->enabled == SD_EVENT_OFF)
+ continue;
+
+ r = source_set_pending(s, true);
+ if (r < 0)
+ return r;
+ }
+ }
+ } else {
+ struct inode_data *inode_data;
+ sd_event_source *s;
+
+ /* Find the inode object for this watch descriptor. If IN_IGNORED is set we also remove it from
+ * our watch descriptor table. */
+ if (d->buffer.ev.mask & IN_IGNORED) {
+
+ inode_data = hashmap_remove(d->wd, INT_TO_PTR(d->buffer.ev.wd));
+ if (!inode_data) {
+ event_inotify_data_drop(e, d, sz);
+ continue;
+ }
+
+ /* The watch descriptor was removed by the kernel, let's drop it here too */
+ inode_data->wd = -1;
+ } else {
+ inode_data = hashmap_get(d->wd, INT_TO_PTR(d->buffer.ev.wd));
+ if (!inode_data) {
+ event_inotify_data_drop(e, d, sz);
+ continue;
+ }
+ }
+
+ /* Trigger all event sources that are interested in these events. Also trigger all event
+ * sources if IN_IGNORED or IN_UNMOUNT is set. */
+ LIST_FOREACH(inotify.by_inode_data, s, inode_data->event_sources) {
+
+ if (s->enabled == SD_EVENT_OFF)
+ continue;
+
+ if ((d->buffer.ev.mask & (IN_IGNORED|IN_UNMOUNT)) == 0 &&
+ (s->inotify.mask & d->buffer.ev.mask & IN_ALL_EVENTS) == 0)
+ continue;
+
+ r = source_set_pending(s, true);
+ if (r < 0)
+ return r;
+ }
+ }
+
+ /* Something pending now? If so, let's finish, otherwise let's read more. */
+ if (d->n_pending > 0)
+ return 1;
+ }
+
+ return 0;
+}
+
+static int process_inotify(sd_event *e) {
+ struct inotify_data *d;
+ int r, done = 0;
+
+ assert(e);
+
+ LIST_FOREACH(buffered, d, e->inotify_data_buffered) {
+ r = event_inotify_data_process(e, d);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ done ++;
+ }
+
+ return done;
+}
+
+static int source_dispatch(sd_event_source *s) {
+ _cleanup_(sd_event_unrefp) sd_event *saved_event = NULL;
+ EventSourceType saved_type;
+ int r = 0;
+
+ assert(s);
+ assert(s->pending || s->type == SOURCE_EXIT);
+
+ /* Save the event source type, here, so that we still know it after the event callback which might
+ * invalidate the event. */
+ saved_type = s->type;
+
+ /* Similar, store a reference to the event loop object, so that we can still access it after the
+ * callback might have invalidated/disconnected the event source. */
+ saved_event = sd_event_ref(s->event);
+
+ if (!IN_SET(s->type, SOURCE_DEFER, SOURCE_EXIT)) {
+ r = source_set_pending(s, false);
+ if (r < 0)
+ return r;
+ }
+
+ if (s->type != SOURCE_POST) {
+ sd_event_source *z;
+
+ /* If we execute a non-post source, let's mark all
+ * post sources as pending */
+
+ SET_FOREACH(z, s->event->post_sources) {
+ 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 = IN_SET(s->child.siginfo.si_code, CLD_EXITED, CLD_KILLED, CLD_DUMPED);
+
+ r = s->child.callback(s, &s->child.siginfo, s->userdata);
+
+ /* Now, reap the PID for good. */
+ if (zombie) {
+ (void) waitid(P_PID, s->child.pid, &s->child.siginfo, WNOHANG|WEXITED);
+ s->child.waited = true;
+ }
+
+ 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_INOTIFY: {
+ struct sd_event *e = s->event;
+ struct inotify_data *d;
+ size_t sz;
+
+ assert(s->inotify.inode_data);
+ assert_se(d = s->inotify.inode_data->inotify_data);
+
+ assert(d->buffer_filled >= offsetof(struct inotify_event, name));
+ sz = offsetof(struct inotify_event, name) + d->buffer.ev.len;
+ assert(d->buffer_filled >= sz);
+
+ r = s->inotify.callback(s, &d->buffer.ev, s->userdata);
+
+ /* When no event is pending anymore on this inotify object, then let's drop the event from the
+ * buffer. */
+ if (d->n_pending == 0)
+ event_inotify_data_drop(e, d, sz);
+
+ 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, %s: %m",
+ strna(s->description),
+ event_source_type_to_string(saved_type),
+ s->exit_on_failure ? "exiting" : "disabling");
+
+ if (s->exit_on_failure)
+ (void) sd_event_exit(saved_event, 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_errno(r, "Prepare callback of event source %s (type %s) returned error, %s: %m",
+ strna(s->description),
+ event_source_type_to_string(s->type),
+ s->exit_on_failure ? "exiting" : "disabling");
+
+ if (s->exit_on_failure)
+ (void) sd_event_exit(e, 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;
+ _cleanup_(sd_event_unrefp) sd_event *ref = NULL;
+ int r;
+
+ assert(e);
+
+ p = prioq_peek(e->exit);
+ if (!p || p->enabled == SD_EVENT_OFF) {
+ e->state = SD_EVENT_FINISHED;
+ return 0;
+ }
+
+ ref = sd_event_ref(e);
+ e->iteration++;
+ e->state = SD_EVENT_EXITING;
+ r = source_dispatch(p);
+ e->state = SD_EVENT_INITIAL;
+ 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;
+
+ 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;
+
+ if (timerfd_settime(e->watchdog_fd, TFD_TIMER_ABSTIME, &its, NULL) < 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);
+}
+
+static void event_close_inode_data_fds(sd_event *e) {
+ struct inode_data *d;
+
+ assert(e);
+
+ /* Close the fds pointing to the inodes to watch now. We need to close them as they might otherwise pin
+ * filesystems. But we can't close them right-away as we need them as long as the user still wants to make
+ * adjustments to the even source, such as changing the priority (which requires us to remove and re-add a watch
+ * for the inode). Hence, let's close them when entering the first iteration after they were added, as a
+ * compromise. */
+
+ while ((d = e->inode_data_to_close)) {
+ assert(d->fd >= 0);
+ d->fd = safe_close(d->fd);
+
+ LIST_REMOVE(to_close, e->inode_data_to_close, d);
+ }
+}
+
+_public_ int sd_event_prepare(sd_event *e) {
+ int r;
+
+ assert_return(e, -EINVAL);
+ assert_return(e = event_resolve(e), -ENOPKG);
+ assert_return(!event_pid_changed(e), -ECHILD);
+ assert_return(e->state != SD_EVENT_FINISHED, -ESTALE);
+ assert_return(e->state == SD_EVENT_INITIAL, -EBUSY);
+
+ /* Let's check that if we are a default event loop we are executed in the correct thread. We only do
+ * this check here once, since gettid() is typically not cached, and thus want to minimize
+ * syscalls */
+ assert_return(!e->default_event_ptr || e->tid == gettid(), -EREMOTEIO);
+
+ 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;
+
+ event_close_inode_data_fds(e);
+
+ 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) {
+ size_t event_queue_max;
+ int r, m, i;
+
+ assert_return(e, -EINVAL);
+ assert_return(e = event_resolve(e), -ENOPKG);
+ 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;
+ }
+
+ event_queue_max = MAX(e->n_sources, 1u);
+ if (!GREEDY_REALLOC(e->event_queue, e->event_queue_allocated, event_queue_max))
+ return -ENOMEM;
+
+ /* If we still have inotify data buffered, then query the other fds, but don't wait on it */
+ if (e->inotify_data_buffered)
+ timeout = 0;
+
+ m = epoll_wait(e->epoll_fd, e->event_queue, event_queue_max,
+ timeout == (uint64_t) -1 ? -1 : (int) DIV_ROUND_UP(timeout, USEC_PER_MSEC));
+ if (m < 0) {
+ if (errno == EINTR) {
+ e->state = SD_EVENT_PENDING;
+ return 1;
+ }
+
+ r = -errno;
+ goto finish;
+ }
+
+ triple_timestamp_get(&e->timestamp);
+
+ for (i = 0; i < m; i++) {
+
+ if (e->event_queue[i].data.ptr == INT_TO_PTR(SOURCE_WATCHDOG))
+ r = flush_timer(e, e->watchdog_fd, e->event_queue[i].events, NULL);
+ else {
+ WakeupType *t = e->event_queue[i].data.ptr;
+
+ switch (*t) {
+
+ case WAKEUP_EVENT_SOURCE: {
+ sd_event_source *s = e->event_queue[i].data.ptr;
+
+ assert(s);
+
+ switch (s->type) {
+
+ case SOURCE_IO:
+ r = process_io(e, s, e->event_queue[i].events);
+ break;
+
+ case SOURCE_CHILD:
+ r = process_pidfd(e, s, e->event_queue[i].events);
+ break;
+
+ default:
+ assert_not_reached("Unexpected event source type");
+ }
+
+ break;
+ }
+
+ case WAKEUP_CLOCK_DATA: {
+ struct clock_data *d = e->event_queue[i].data.ptr;
+
+ assert(d);
+
+ r = flush_timer(e, d->fd, e->event_queue[i].events, &d->next);
+ break;
+ }
+
+ case WAKEUP_SIGNAL_DATA:
+ r = process_signal(e, e->event_queue[i].data.ptr, e->event_queue[i].events);
+ break;
+
+ case WAKEUP_INOTIFY_DATA:
+ r = event_inotify_data_read(e, e->event_queue[i].data.ptr, e->event_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;
+ }
+
+ r = process_inotify(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(e = event_resolve(e), -ENOPKG);
+ 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) {
+ _cleanup_(sd_event_unrefp) sd_event *ref = NULL;
+
+ ref = sd_event_ref(e);
+ e->state = SD_EVENT_RUNNING;
+ r = source_dispatch(p);
+ e->state = SD_EVENT_INITIAL;
+ 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], *p;
+ size_t l, i;
+
+ p = b;
+ l = sizeof(b);
+ for (i = 0; i < ELEMENTSOF(e->delays); i++) {
+ l = strpcpyf(&p, l, "%u ", e->delays[i]);
+ e->delays[i] = 0;
+ }
+ log_debug("Event loop iterations: %s", b);
+}
+
+_public_ int sd_event_run(sd_event *e, uint64_t timeout) {
+ int r;
+
+ assert_return(e, -EINVAL);
+ assert_return(e = event_resolve(e), -ENOPKG);
+ 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 < ELEMENTSOF(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) {
+ _cleanup_(sd_event_unrefp) sd_event *ref = NULL;
+ int r;
+
+ assert_return(e, -EINVAL);
+ assert_return(e = event_resolve(e), -ENOPKG);
+ assert_return(!event_pid_changed(e), -ECHILD);
+ assert_return(e->state == SD_EVENT_INITIAL, -EBUSY);
+
+ ref = sd_event_ref(e);
+
+ while (e->state != SD_EVENT_FINISHED) {
+ r = sd_event_run(e, (uint64_t) -1);
+ if (r < 0)
+ return r;
+ }
+
+ return e->exit_code;
+}
+
+_public_ int sd_event_get_fd(sd_event *e) {
+ assert_return(e, -EINVAL);
+ assert_return(e = event_resolve(e), -ENOPKG);
+ 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(e = event_resolve(e), -ENOPKG);
+ 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(e = event_resolve(e), -ENOPKG);
+ 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 = event_resolve(e), -ENOPKG);
+ 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(e = event_resolve(e), -ENOPKG);
+ assert_return(usec, -EINVAL);
+ assert_return(!event_pid_changed(e), -ECHILD);
+
+ if (!TRIPLE_TIMESTAMP_HAS_CLOCK(clock))
+ return -EOPNOTSUPP;
+
+ /* Generate a clean error in case CLOCK_BOOTTIME is not available. Note that don't use clock_supported() here,
+ * for a reason: there are systems where CLOCK_BOOTTIME is supported, but CLOCK_BOOTTIME_ALARM is not, but for
+ * the purpose of getting the time this doesn't matter. */
+ if (IN_SET(clock, CLOCK_BOOTTIME, CLOCK_BOOTTIME_ALARM) && !clock_boottime_supported())
+ return -EOPNOTSUPP;
+
+ if (!triple_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;
+ }
+
+ *usec = triple_timestamp_by_clock(&e->timestamp, clock);
+ return 0;
+}
+
+_public_ int sd_event_default(sd_event **ret) {
+ 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(e = event_resolve(e), -ENOPKG);
+ 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(e = event_resolve(e), -ENOPKG);
+ assert_return(!event_pid_changed(e), -ECHILD);
+
+ if (e->watchdog == !!b)
+ return e->watchdog;
+
+ if (b) {
+ 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;
+
+ struct epoll_event ev = {
+ .events = EPOLLIN,
+ .data.ptr = INT_TO_PTR(SOURCE_WATCHDOG),
+ };
+
+ if (epoll_ctl(e->epoll_fd, EPOLL_CTL_ADD, e->watchdog_fd, &ev) < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ } else {
+ if (e->watchdog_fd >= 0) {
+ (void) 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(e = event_resolve(e), -ENOPKG);
+ assert_return(!event_pid_changed(e), -ECHILD);
+
+ return e->watchdog;
+}
+
+_public_ int sd_event_get_iteration(sd_event *e, uint64_t *ret) {
+ assert_return(e, -EINVAL);
+ assert_return(e = event_resolve(e), -ENOPKG);
+ assert_return(!event_pid_changed(e), -ECHILD);
+
+ *ret = e->iteration;
+ return 0;
+}
+
+_public_ int sd_event_source_set_destroy_callback(sd_event_source *s, sd_event_destroy_t callback) {
+ assert_return(s, -EINVAL);
+
+ s->destroy_callback = callback;
+ return 0;
+}
+
+_public_ int sd_event_source_get_destroy_callback(sd_event_source *s, sd_event_destroy_t *ret) {
+ assert_return(s, -EINVAL);
+
+ if (ret)
+ *ret = s->destroy_callback;
+
+ return !!s->destroy_callback;
+}
+
+_public_ int sd_event_source_get_floating(sd_event_source *s) {
+ assert_return(s, -EINVAL);
+
+ return s->floating;
+}
+
+_public_ int sd_event_source_set_floating(sd_event_source *s, int b) {
+ assert_return(s, -EINVAL);
+
+ if (s->floating == !!b)
+ return 0;
+
+ if (!s->event) /* Already disconnected */
+ return -ESTALE;
+
+ s->floating = b;
+
+ if (b) {
+ sd_event_source_ref(s);
+ sd_event_unref(s->event);
+ } else {
+ sd_event_ref(s->event);
+ sd_event_source_unref(s);
+ }
+
+ return 1;
+}
+
+_public_ int sd_event_source_get_exit_on_failure(sd_event_source *s) {
+ assert_return(s, -EINVAL);
+ assert_return(s->type != SOURCE_EXIT, -EDOM);
+
+ return s->exit_on_failure;
+}
+
+_public_ int sd_event_source_set_exit_on_failure(sd_event_source *s, int b) {
+ assert_return(s, -EINVAL);
+ assert_return(s->type != SOURCE_EXIT, -EDOM);
+
+ if (s->exit_on_failure == !!b)
+ return 0;
+
+ s->exit_on_failure = b;
+ return 1;
+}