1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
4 This file is part of systemd.
6 Copyright 2010 Lennart Poettering
8 systemd is free software; you can redistribute it and/or modify it
9 under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
13 systemd is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with systemd; If not, see <http://www.gnu.org/licenses/>.
22 #include <sys/inotify.h>
23 #include <sys/epoll.h>
24 #include <sys/ioctl.h>
29 #include "unit-name.h"
31 #include "dbus-path.h"
33 #include "bus-errors.h"
35 static const UnitActiveState state_translation_table[_PATH_STATE_MAX] = {
36 [PATH_DEAD] = UNIT_INACTIVE,
37 [PATH_WAITING] = UNIT_ACTIVE,
38 [PATH_RUNNING] = UNIT_ACTIVE,
39 [PATH_FAILED] = UNIT_FAILED
42 int pathspec_watch(PathSpec *s, Unit *u) {
43 static const int flags_table[_PATH_TYPE_MAX] = {
44 [PATH_EXISTS] = IN_DELETE_SELF|IN_MOVE_SELF|IN_ATTRIB,
45 [PATH_EXISTS_GLOB] = IN_DELETE_SELF|IN_MOVE_SELF|IN_ATTRIB,
46 [PATH_CHANGED] = IN_DELETE_SELF|IN_MOVE_SELF|IN_ATTRIB|IN_CLOSE_WRITE|IN_CREATE|IN_DELETE|IN_MOVED_FROM|IN_MOVED_TO,
47 [PATH_MODIFIED] = IN_DELETE_SELF|IN_MOVE_SELF|IN_ATTRIB|IN_CLOSE_WRITE|IN_CREATE|IN_DELETE|IN_MOVED_FROM|IN_MOVED_TO|IN_MODIFY,
48 [PATH_DIRECTORY_NOT_EMPTY] = IN_DELETE_SELF|IN_MOVE_SELF|IN_ATTRIB|IN_CREATE|IN_MOVED_TO
58 pathspec_unwatch(s, u);
60 if (!(k = strdup(s->path)))
63 if ((s->inotify_fd = inotify_init1(IN_NONBLOCK|IN_CLOEXEC)) < 0) {
68 if (unit_watch_fd(u, s->inotify_fd, EPOLLIN, &s->watch) < 0) {
73 if ((s->primary_wd = inotify_add_watch(s->inotify_fd, k, flags_table[s->type])) >= 0)
79 /* This assumes the path was passed through path_kill_slashes()! */
80 if (!(slash = strrchr(k, '/')))
83 /* Trim the path at the last slash. Keep the slash if it's the root dir. */
84 slash[slash == k] = 0;
88 flags |= IN_DELETE_SELF | IN_ATTRIB | IN_CREATE | IN_MOVED_TO;
90 if (inotify_add_watch(s->inotify_fd, k, flags) >= 0)
99 pathspec_unwatch(s, u);
103 void pathspec_unwatch(PathSpec *s, Unit *u) {
105 if (s->inotify_fd < 0)
108 unit_unwatch_fd(u, &s->watch);
110 close_nointr_nofail(s->inotify_fd);
114 int pathspec_fd_event(PathSpec *s, uint32_t events) {
116 struct inotify_event *e;
121 if (events != EPOLLIN) {
122 log_error("Got Invalid poll event on inotify.");
127 if (ioctl(s->inotify_fd, FIONREAD, &l) < 0) {
128 log_error("FIONREAD failed: %m");
135 if (!(buf = malloc(l))) {
136 log_error("Failed to allocate buffer: %m");
141 if ((k = read(s->inotify_fd, buf, l)) < 0) {
142 log_error("Failed to read inotify event: %m");
147 e = (struct inotify_event*) buf;
152 if (s->type == PATH_CHANGED && s->primary_wd == e->wd)
155 step = sizeof(struct inotify_event) + e->len;
156 assert(step <= (size_t) k);
158 e = (struct inotify_event*) ((uint8_t*) e + step);
166 static bool pathspec_check_good(PathSpec *s, bool initial) {
172 good = access(s->path, F_OK) >= 0;
175 case PATH_EXISTS_GLOB:
176 good = glob_exists(s->path) > 0;
179 case PATH_DIRECTORY_NOT_EMPTY: {
182 k = dir_is_empty(s->path);
183 good = !(k == -ENOENT || k > 0);
190 b = access(s->path, F_OK) >= 0;
191 good = !initial && b != s->previous_exists;
192 s->previous_exists = b;
203 static bool pathspec_startswith(PathSpec *s, const char *what) {
204 return path_startswith(s->path, what);
207 static void pathspec_mkdir(PathSpec *s, mode_t mode) {
210 if (s->type == PATH_EXISTS || s->type == PATH_EXISTS_GLOB)
213 if ((r = mkdir_p(s->path, mode)) < 0)
214 log_warning("mkdir(%s) failed: %s", s->path, strerror(-r));
217 static void pathspec_dump(PathSpec *s, FILE *f, const char *prefix) {
221 path_type_to_string(s->type),
225 void pathspec_done(PathSpec *s) {
226 assert(s->inotify_fd == -1);
230 static void path_init(Unit *u) {
234 assert(u->meta.load_state == UNIT_STUB);
236 p->directory_mode = 0755;
239 static void path_done(Unit *u) {
245 while ((s = p->specs)) {
246 pathspec_unwatch(s, u);
247 LIST_REMOVE(PathSpec, spec, p->specs, s);
253 int path_add_one_mount_link(Path *p, Mount *m) {
260 if (p->meta.load_state != UNIT_LOADED ||
261 m->meta.load_state != UNIT_LOADED)
264 LIST_FOREACH(spec, s, p->specs) {
266 if (!pathspec_startswith(s, m->where))
269 if ((r = unit_add_two_dependencies(UNIT(p), UNIT_AFTER, UNIT_REQUIRES, UNIT(m), true)) < 0)
276 static int path_add_mount_links(Path *p) {
282 LIST_FOREACH(units_by_type, other, p->meta.manager->units_by_type[UNIT_MOUNT])
283 if ((r = path_add_one_mount_link(p, (Mount*) other)) < 0)
289 static int path_verify(Path *p) {
292 if (p->meta.load_state != UNIT_LOADED)
296 log_error("%s lacks path setting. Refusing.", p->meta.id);
303 static int path_add_default_dependencies(Path *p) {
308 if (p->meta.manager->running_as == MANAGER_SYSTEM) {
309 if ((r = unit_add_dependency_by_name(UNIT(p), UNIT_BEFORE, SPECIAL_BASIC_TARGET, NULL, true)) < 0)
312 if ((r = unit_add_two_dependencies_by_name(UNIT(p), UNIT_AFTER, UNIT_REQUIRES, SPECIAL_SYSINIT_TARGET, NULL, true)) < 0)
316 return unit_add_two_dependencies_by_name(UNIT(p), UNIT_BEFORE, UNIT_CONFLICTS, SPECIAL_SHUTDOWN_TARGET, NULL, true);
319 static int path_load(Unit *u) {
324 assert(u->meta.load_state == UNIT_STUB);
326 if ((r = unit_load_fragment_and_dropin(u)) < 0)
329 if (u->meta.load_state == UNIT_LOADED) {
332 if ((r = unit_load_related_unit(u, ".service", &p->unit)))
335 if ((r = unit_add_dependency(u, UNIT_BEFORE, p->unit, true)) < 0)
338 if ((r = path_add_mount_links(p)) < 0)
341 if (p->meta.default_dependencies)
342 if ((r = path_add_default_dependencies(p)) < 0)
346 return path_verify(p);
349 static void path_dump(Unit *u, FILE *f, const char *prefix) {
359 "%sMakeDirectory: %s\n"
360 "%sDirectoryMode: %04o\n",
361 prefix, path_state_to_string(p->state),
362 prefix, p->unit->meta.id,
363 prefix, yes_no(p->make_directory),
364 prefix, p->directory_mode);
366 LIST_FOREACH(spec, s, p->specs)
367 pathspec_dump(s, f, prefix);
370 static void path_unwatch(Path *p) {
375 LIST_FOREACH(spec, s, p->specs)
376 pathspec_unwatch(s, UNIT(p));
379 static int path_watch(Path *p) {
385 LIST_FOREACH(spec, s, p->specs)
386 if ((r = pathspec_watch(s, UNIT(p))) < 0)
392 static void path_set_state(Path *p, PathState state) {
396 old_state = p->state;
399 if (state != PATH_WAITING &&
400 (state != PATH_RUNNING || p->inotify_triggered))
403 if (state != old_state)
404 log_debug("%s changed %s -> %s",
406 path_state_to_string(old_state),
407 path_state_to_string(state));
409 unit_notify(UNIT(p), state_translation_table[old_state], state_translation_table[state], true);
412 static void path_enter_waiting(Path *p, bool initial, bool recheck);
414 static int path_coldplug(Unit *u) {
418 assert(p->state == PATH_DEAD);
420 if (p->deserialized_state != p->state) {
422 if (p->deserialized_state == PATH_WAITING ||
423 p->deserialized_state == PATH_RUNNING)
424 path_enter_waiting(p, true, true);
426 path_set_state(p, p->deserialized_state);
432 static void path_enter_dead(Path *p, bool success) {
438 path_set_state(p, p->failure ? PATH_FAILED : PATH_DEAD);
441 static void path_enter_running(Path *p) {
446 dbus_error_init(&error);
448 /* Don't start job if we are supposed to go down */
449 if (p->meta.job && p->meta.job->type == JOB_STOP)
452 if ((r = manager_add_job(p->meta.manager, JOB_START, p->unit, JOB_REPLACE, true, &error, NULL)) < 0)
455 p->inotify_triggered = false;
457 if ((r = path_watch(p)) < 0)
460 path_set_state(p, PATH_RUNNING);
464 log_warning("%s failed to queue unit startup job: %s", p->meta.id, bus_error(&error, r));
465 path_enter_dead(p, false);
467 dbus_error_free(&error);
470 static bool path_check_good(Path *p, bool initial) {
476 LIST_FOREACH(spec, s, p->specs) {
477 good = pathspec_check_good(s, initial);
486 static void path_enter_waiting(Path *p, bool initial, bool recheck) {
490 if (path_check_good(p, initial)) {
491 log_debug("%s got triggered.", p->meta.id);
492 path_enter_running(p);
496 if ((r = path_watch(p)) < 0)
499 /* Hmm, so now we have created inotify watches, but the file
500 * might have appeared/been removed by now, so we must
504 if (path_check_good(p, false)) {
505 log_debug("%s got triggered.", p->meta.id);
506 path_enter_running(p);
510 path_set_state(p, PATH_WAITING);
514 log_warning("%s failed to enter waiting state: %s", p->meta.id, strerror(-r));
515 path_enter_dead(p, false);
518 static void path_mkdir(Path *p) {
523 if (!p->make_directory)
526 LIST_FOREACH(spec, s, p->specs)
527 pathspec_mkdir(s, p->directory_mode);
530 static int path_start(Unit *u) {
534 assert(p->state == PATH_DEAD || p->state == PATH_FAILED);
536 if (p->unit->meta.load_state != UNIT_LOADED)
542 path_enter_waiting(p, true, true);
547 static int path_stop(Unit *u) {
551 assert(p->state == PATH_WAITING || p->state == PATH_RUNNING);
553 path_enter_dead(p, true);
557 static int path_serialize(Unit *u, FILE *f, FDSet *fds) {
564 unit_serialize_item(u, f, "state", path_state_to_string(p->state));
569 static int path_deserialize_item(Unit *u, const char *key, const char *value, FDSet *fds) {
577 if (streq(key, "state")) {
580 if ((state = path_state_from_string(value)) < 0)
581 log_debug("Failed to parse state value %s", value);
583 p->deserialized_state = state;
585 log_debug("Unknown serialization key '%s'", key);
590 static UnitActiveState path_active_state(Unit *u) {
593 return state_translation_table[PATH(u)->state];
596 static const char *path_sub_state_to_string(Unit *u) {
599 return path_state_to_string(PATH(u)->state);
602 static void path_fd_event(Unit *u, int fd, uint32_t events, Watch *w) {
610 if (p->state != PATH_WAITING &&
611 p->state != PATH_RUNNING)
614 /* log_debug("inotify wakeup on %s.", u->meta.id); */
616 LIST_FOREACH(spec, s, p->specs)
617 if (pathspec_owns_inotify_fd(s, fd))
621 log_error("Got event on unknown fd.");
625 changed = pathspec_fd_event(s, events);
629 /* If we are already running, then remember that one event was
630 * dispatched so that we restart the service only if something
631 * actually changed on disk */
632 p->inotify_triggered = true;
635 path_enter_running(p);
637 path_enter_waiting(p, false, true);
642 path_enter_dead(p, false);
645 void path_unit_notify(Unit *u, UnitActiveState new_state) {
650 if (u->meta.type == UNIT_PATH)
653 SET_FOREACH(n, u->meta.names, i) {
658 if (!(k = unit_name_change_suffix(n, ".path"))) {
663 t = manager_get_unit(u->meta.manager, k);
669 if (t->meta.load_state != UNIT_LOADED)
677 if (p->state == PATH_RUNNING && new_state == UNIT_INACTIVE) {
678 log_debug("%s got notified about unit deactivation.", p->meta.id);
680 /* Hmm, so inotify was triggered since the
681 * last activation, so I guess we need to
682 * recheck what is going on. */
683 path_enter_waiting(p, false, p->inotify_triggered);
690 log_error("Failed find path unit: %s", strerror(-r));
693 static void path_reset_failed(Unit *u) {
698 if (p->state == PATH_FAILED)
699 path_set_state(p, PATH_DEAD);
704 static const char* const path_state_table[_PATH_STATE_MAX] = {
705 [PATH_DEAD] = "dead",
706 [PATH_WAITING] = "waiting",
707 [PATH_RUNNING] = "running",
708 [PATH_FAILED] = "failed"
711 DEFINE_STRING_TABLE_LOOKUP(path_state, PathState);
713 static const char* const path_type_table[_PATH_TYPE_MAX] = {
714 [PATH_EXISTS] = "PathExists",
715 [PATH_EXISTS_GLOB] = "PathExistsGlob",
716 [PATH_CHANGED] = "PathChanged",
717 [PATH_MODIFIED] = "PathModified",
718 [PATH_DIRECTORY_NOT_EMPTY] = "DirectoryNotEmpty"
721 DEFINE_STRING_TABLE_LOOKUP(path_type, PathType);
723 const UnitVTable path_vtable = {
734 .coldplug = path_coldplug,
741 .serialize = path_serialize,
742 .deserialize_item = path_deserialize_item,
744 .active_state = path_active_state,
745 .sub_state_to_string = path_sub_state_to_string,
747 .fd_event = path_fd_event,
749 .reset_failed = path_reset_failed,
751 .bus_interface = "org.freedesktop.systemd1.Path",
752 .bus_message_handler = bus_path_message_handler