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->type == PATH_MODIFIED) &&
153 s->primary_wd == e->wd)
156 step = sizeof(struct inotify_event) + e->len;
157 assert(step <= (size_t) k);
159 e = (struct inotify_event*) ((uint8_t*) e + step);
167 static bool pathspec_check_good(PathSpec *s, bool initial) {
173 good = access(s->path, F_OK) >= 0;
176 case PATH_EXISTS_GLOB:
177 good = glob_exists(s->path) > 0;
180 case PATH_DIRECTORY_NOT_EMPTY: {
183 k = dir_is_empty(s->path);
184 good = !(k == -ENOENT || k > 0);
189 case PATH_MODIFIED: {
192 b = access(s->path, F_OK) >= 0;
193 good = !initial && b != s->previous_exists;
194 s->previous_exists = b;
205 static bool pathspec_startswith(PathSpec *s, const char *what) {
206 return path_startswith(s->path, what);
209 static void pathspec_mkdir(PathSpec *s, mode_t mode) {
212 if (s->type == PATH_EXISTS || s->type == PATH_EXISTS_GLOB)
215 if ((r = mkdir_p(s->path, mode)) < 0)
216 log_warning("mkdir(%s) failed: %s", s->path, strerror(-r));
219 static void pathspec_dump(PathSpec *s, FILE *f, const char *prefix) {
223 path_type_to_string(s->type),
227 void pathspec_done(PathSpec *s) {
228 assert(s->inotify_fd == -1);
232 static void path_init(Unit *u) {
236 assert(u->meta.load_state == UNIT_STUB);
238 p->directory_mode = 0755;
241 static void path_done(Unit *u) {
247 while ((s = p->specs)) {
248 pathspec_unwatch(s, u);
249 LIST_REMOVE(PathSpec, spec, p->specs, s);
255 int path_add_one_mount_link(Path *p, Mount *m) {
262 if (p->meta.load_state != UNIT_LOADED ||
263 m->meta.load_state != UNIT_LOADED)
266 LIST_FOREACH(spec, s, p->specs) {
268 if (!pathspec_startswith(s, m->where))
271 if ((r = unit_add_two_dependencies(UNIT(p), UNIT_AFTER, UNIT_REQUIRES, UNIT(m), true)) < 0)
278 static int path_add_mount_links(Path *p) {
284 LIST_FOREACH(units_by_type, other, p->meta.manager->units_by_type[UNIT_MOUNT])
285 if ((r = path_add_one_mount_link(p, (Mount*) other)) < 0)
291 static int path_verify(Path *p) {
294 if (p->meta.load_state != UNIT_LOADED)
298 log_error("%s lacks path setting. Refusing.", p->meta.id);
305 static int path_add_default_dependencies(Path *p) {
310 if (p->meta.manager->running_as == MANAGER_SYSTEM) {
311 if ((r = unit_add_dependency_by_name(UNIT(p), UNIT_BEFORE, SPECIAL_BASIC_TARGET, NULL, true)) < 0)
314 if ((r = unit_add_two_dependencies_by_name(UNIT(p), UNIT_AFTER, UNIT_REQUIRES, SPECIAL_SYSINIT_TARGET, NULL, true)) < 0)
318 return unit_add_two_dependencies_by_name(UNIT(p), UNIT_BEFORE, UNIT_CONFLICTS, SPECIAL_SHUTDOWN_TARGET, NULL, true);
321 static int path_load(Unit *u) {
326 assert(u->meta.load_state == UNIT_STUB);
328 if ((r = unit_load_fragment_and_dropin(u)) < 0)
331 if (u->meta.load_state == UNIT_LOADED) {
334 if ((r = unit_load_related_unit(u, ".service", &p->unit)))
337 if ((r = unit_add_dependency(u, UNIT_BEFORE, p->unit, true)) < 0)
340 if ((r = path_add_mount_links(p)) < 0)
343 if (p->meta.default_dependencies)
344 if ((r = path_add_default_dependencies(p)) < 0)
348 return path_verify(p);
351 static void path_dump(Unit *u, FILE *f, const char *prefix) {
361 "%sMakeDirectory: %s\n"
362 "%sDirectoryMode: %04o\n",
363 prefix, path_state_to_string(p->state),
364 prefix, p->unit->meta.id,
365 prefix, yes_no(p->make_directory),
366 prefix, p->directory_mode);
368 LIST_FOREACH(spec, s, p->specs)
369 pathspec_dump(s, f, prefix);
372 static void path_unwatch(Path *p) {
377 LIST_FOREACH(spec, s, p->specs)
378 pathspec_unwatch(s, UNIT(p));
381 static int path_watch(Path *p) {
387 LIST_FOREACH(spec, s, p->specs)
388 if ((r = pathspec_watch(s, UNIT(p))) < 0)
394 static void path_set_state(Path *p, PathState state) {
398 old_state = p->state;
401 if (state != PATH_WAITING &&
402 (state != PATH_RUNNING || p->inotify_triggered))
405 if (state != old_state)
406 log_debug("%s changed %s -> %s",
408 path_state_to_string(old_state),
409 path_state_to_string(state));
411 unit_notify(UNIT(p), state_translation_table[old_state], state_translation_table[state], true);
414 static void path_enter_waiting(Path *p, bool initial, bool recheck);
416 static int path_coldplug(Unit *u) {
420 assert(p->state == PATH_DEAD);
422 if (p->deserialized_state != p->state) {
424 if (p->deserialized_state == PATH_WAITING ||
425 p->deserialized_state == PATH_RUNNING)
426 path_enter_waiting(p, true, true);
428 path_set_state(p, p->deserialized_state);
434 static void path_enter_dead(Path *p, bool success) {
440 path_set_state(p, p->failure ? PATH_FAILED : PATH_DEAD);
443 static void path_enter_running(Path *p) {
448 dbus_error_init(&error);
450 /* Don't start job if we are supposed to go down */
451 if (p->meta.job && p->meta.job->type == JOB_STOP)
454 if ((r = manager_add_job(p->meta.manager, JOB_START, p->unit, JOB_REPLACE, true, &error, NULL)) < 0)
457 p->inotify_triggered = false;
459 if ((r = path_watch(p)) < 0)
462 path_set_state(p, PATH_RUNNING);
466 log_warning("%s failed to queue unit startup job: %s", p->meta.id, bus_error(&error, r));
467 path_enter_dead(p, false);
469 dbus_error_free(&error);
472 static bool path_check_good(Path *p, bool initial) {
478 LIST_FOREACH(spec, s, p->specs) {
479 good = pathspec_check_good(s, initial);
488 static void path_enter_waiting(Path *p, bool initial, bool recheck) {
492 if (path_check_good(p, initial)) {
493 log_debug("%s got triggered.", p->meta.id);
494 path_enter_running(p);
498 if ((r = path_watch(p)) < 0)
501 /* Hmm, so now we have created inotify watches, but the file
502 * might have appeared/been removed by now, so we must
506 if (path_check_good(p, false)) {
507 log_debug("%s got triggered.", p->meta.id);
508 path_enter_running(p);
512 path_set_state(p, PATH_WAITING);
516 log_warning("%s failed to enter waiting state: %s", p->meta.id, strerror(-r));
517 path_enter_dead(p, false);
520 static void path_mkdir(Path *p) {
525 if (!p->make_directory)
528 LIST_FOREACH(spec, s, p->specs)
529 pathspec_mkdir(s, p->directory_mode);
532 static int path_start(Unit *u) {
536 assert(p->state == PATH_DEAD || p->state == PATH_FAILED);
538 if (p->unit->meta.load_state != UNIT_LOADED)
544 path_enter_waiting(p, true, true);
549 static int path_stop(Unit *u) {
553 assert(p->state == PATH_WAITING || p->state == PATH_RUNNING);
555 path_enter_dead(p, true);
559 static int path_serialize(Unit *u, FILE *f, FDSet *fds) {
566 unit_serialize_item(u, f, "state", path_state_to_string(p->state));
571 static int path_deserialize_item(Unit *u, const char *key, const char *value, FDSet *fds) {
579 if (streq(key, "state")) {
582 if ((state = path_state_from_string(value)) < 0)
583 log_debug("Failed to parse state value %s", value);
585 p->deserialized_state = state;
587 log_debug("Unknown serialization key '%s'", key);
592 static UnitActiveState path_active_state(Unit *u) {
595 return state_translation_table[PATH(u)->state];
598 static const char *path_sub_state_to_string(Unit *u) {
601 return path_state_to_string(PATH(u)->state);
604 static void path_fd_event(Unit *u, int fd, uint32_t events, Watch *w) {
612 if (p->state != PATH_WAITING &&
613 p->state != PATH_RUNNING)
616 /* log_debug("inotify wakeup on %s.", u->meta.id); */
618 LIST_FOREACH(spec, s, p->specs)
619 if (pathspec_owns_inotify_fd(s, fd))
623 log_error("Got event on unknown fd.");
627 changed = pathspec_fd_event(s, events);
631 /* If we are already running, then remember that one event was
632 * dispatched so that we restart the service only if something
633 * actually changed on disk */
634 p->inotify_triggered = true;
637 path_enter_running(p);
639 path_enter_waiting(p, false, true);
644 path_enter_dead(p, false);
647 void path_unit_notify(Unit *u, UnitActiveState new_state) {
652 if (u->meta.type == UNIT_PATH)
655 SET_FOREACH(n, u->meta.names, i) {
660 if (!(k = unit_name_change_suffix(n, ".path"))) {
665 t = manager_get_unit(u->meta.manager, k);
671 if (t->meta.load_state != UNIT_LOADED)
679 if (p->state == PATH_RUNNING && new_state == UNIT_INACTIVE) {
680 log_debug("%s got notified about unit deactivation.", p->meta.id);
682 /* Hmm, so inotify was triggered since the
683 * last activation, so I guess we need to
684 * recheck what is going on. */
685 path_enter_waiting(p, false, p->inotify_triggered);
692 log_error("Failed find path unit: %s", strerror(-r));
695 static void path_reset_failed(Unit *u) {
700 if (p->state == PATH_FAILED)
701 path_set_state(p, PATH_DEAD);
706 static const char* const path_state_table[_PATH_STATE_MAX] = {
707 [PATH_DEAD] = "dead",
708 [PATH_WAITING] = "waiting",
709 [PATH_RUNNING] = "running",
710 [PATH_FAILED] = "failed"
713 DEFINE_STRING_TABLE_LOOKUP(path_state, PathState);
715 static const char* const path_type_table[_PATH_TYPE_MAX] = {
716 [PATH_EXISTS] = "PathExists",
717 [PATH_EXISTS_GLOB] = "PathExistsGlob",
718 [PATH_CHANGED] = "PathChanged",
719 [PATH_MODIFIED] = "PathModified",
720 [PATH_DIRECTORY_NOT_EMPTY] = "DirectoryNotEmpty"
723 DEFINE_STRING_TABLE_LOOKUP(path_type, PathType);
725 const UnitVTable path_vtable = {
736 .coldplug = path_coldplug,
743 .serialize = path_serialize,
744 .deserialize_item = path_deserialize_item,
746 .active_state = path_active_state,
747 .sub_state_to_string = path_sub_state_to_string,
749 .fd_event = path_fd_event,
751 .reset_failed = path_reset_failed,
753 .bus_interface = "org.freedesktop.systemd1.Path",
754 .bus_message_handler = bus_path_message_handler