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 static void path_unwatch_one(Path
*p
, PathSpec
*s
) {
44 if (s
->inotify_fd
< 0)
47 unit_unwatch_fd(UNIT(p
), &s
->watch
);
49 close_nointr_nofail(s
->inotify_fd
);
53 static void path_done(Unit
*u
) {
59 while ((s
= p
->specs
)) {
60 path_unwatch_one(p
, s
);
61 LIST_REMOVE(PathSpec
, spec
, p
->specs
, s
);
67 int path_add_one_mount_link(Path
*p
, Mount
*m
) {
74 if (p
->meta
.load_state
!= UNIT_LOADED
||
75 m
->meta
.load_state
!= UNIT_LOADED
)
78 LIST_FOREACH(spec
, s
, p
->specs
) {
80 if (!path_startswith(s
->path
, m
->where
))
83 if ((r
= unit_add_two_dependencies(UNIT(p
), UNIT_AFTER
, UNIT_REQUIRES
, UNIT(m
), true)) < 0)
90 static int path_add_mount_links(Path
*p
) {
96 LIST_FOREACH(units_per_type
, other
, p
->meta
.manager
->units_per_type
[UNIT_MOUNT
])
97 if ((r
= path_add_one_mount_link(p
, (Mount
*) other
)) < 0)
103 static int path_verify(Path
*p
) {
106 if (p
->meta
.load_state
!= UNIT_LOADED
)
110 log_error("%s lacks path setting. Refusing.", p
->meta
.id
);
117 static int path_add_default_dependencies(Path
*p
) {
122 if (p
->meta
.manager
->running_as
== MANAGER_SYSTEM
) {
123 if ((r
= unit_add_dependency_by_name(UNIT(p
), UNIT_BEFORE
, SPECIAL_BASIC_TARGET
, NULL
, true)) < 0)
126 if ((r
= unit_add_two_dependencies_by_name(UNIT(p
), UNIT_AFTER
, UNIT_REQUIRES
, SPECIAL_SYSINIT_TARGET
, NULL
, true)) < 0)
130 return unit_add_two_dependencies_by_name(UNIT(p
), UNIT_BEFORE
, UNIT_CONFLICTS
, SPECIAL_SHUTDOWN_TARGET
, NULL
, true);
133 static int path_load(Unit
*u
) {
138 assert(u
->meta
.load_state
== UNIT_STUB
);
140 if ((r
= unit_load_fragment_and_dropin(u
)) < 0)
143 if (u
->meta
.load_state
== UNIT_LOADED
) {
146 if ((r
= unit_load_related_unit(u
, ".service", &p
->unit
)))
149 if ((r
= unit_add_dependency(u
, UNIT_BEFORE
, p
->unit
, true)) < 0)
152 if ((r
= path_add_mount_links(p
)) < 0)
155 if (p
->meta
.default_dependencies
)
156 if ((r
= path_add_default_dependencies(p
)) < 0)
160 return path_verify(p
);
163 static void path_dump(Unit
*u
, FILE *f
, const char *prefix
) {
173 prefix
, path_state_to_string(p
->state
),
174 prefix
, p
->unit
->meta
.id
);
176 LIST_FOREACH(spec
, s
, p
->specs
)
180 path_type_to_string(s
->type
),
184 static int path_watch_one(Path
*p
, PathSpec
*s
) {
185 static const int flags_table
[_PATH_TYPE_MAX
] = {
186 [PATH_EXISTS
] = IN_DELETE_SELF
|IN_MOVE_SELF
|IN_ATTRIB
,
187 [PATH_CHANGED
] = IN_DELETE_SELF
|IN_MOVE_SELF
|IN_ATTRIB
|IN_CLOSE_WRITE
|IN_CREATE
|IN_DELETE
|IN_MOVED_FROM
|IN_MOVED_TO
,
188 [PATH_DIRECTORY_NOT_EMPTY
] = IN_DELETE_SELF
|IN_MOVE_SELF
|IN_ATTRIB
|IN_CREATE
|IN_MOVED_TO
198 path_unwatch_one(p
, s
);
200 if (!(k
= strdup(s
->path
)))
203 if ((s
->inotify_fd
= inotify_init1(IN_NONBLOCK
|IN_CLOEXEC
)) < 0) {
208 if (unit_watch_fd(UNIT(p
), s
->inotify_fd
, EPOLLIN
, &s
->watch
) < 0) {
213 if ((s
->primary_wd
= inotify_add_watch(s
->inotify_fd
, k
, flags_table
[s
->type
])) >= 0)
219 /* This assumes the path was passed through path_kill_slashes()! */
220 if (!(slash
= strrchr(k
, '/')))
223 /* Trim the path at the last slash. Keep the slash if it's the root dir. */
224 slash
[slash
== k
] = 0;
226 flags
= IN_MOVE_SELF
;
228 flags
|= IN_DELETE_SELF
| IN_ATTRIB
| IN_CREATE
| IN_MOVED_TO
;
230 if (inotify_add_watch(s
->inotify_fd
, k
, flags
) >= 0)
232 } while (slash
!= k
);
239 path_unwatch_one(p
, s
);
243 static void path_unwatch(Path
*p
) {
248 LIST_FOREACH(spec
, s
, p
->specs
)
249 path_unwatch_one(p
, s
);
252 static int path_watch(Path
*p
) {
258 LIST_FOREACH(spec
, s
, p
->specs
)
259 if ((r
= path_watch_one(p
, s
)) < 0)
265 static void path_set_state(Path
*p
, PathState state
) {
269 old_state
= p
->state
;
272 if (state
!= PATH_WAITING
&&
273 (state
!= PATH_RUNNING
|| p
->inotify_triggered
))
276 if (state
!= old_state
)
277 log_debug("%s changed %s -> %s",
279 path_state_to_string(old_state
),
280 path_state_to_string(state
));
282 unit_notify(UNIT(p
), state_translation_table
[old_state
], state_translation_table
[state
], true);
285 static void path_enter_waiting(Path
*p
, bool initial
, bool recheck
, bool skip_watch
);
287 static int path_coldplug(Unit
*u
) {
291 assert(p
->state
== PATH_DEAD
);
293 if (p
->deserialized_state
!= p
->state
) {
295 if (p
->deserialized_state
== PATH_WAITING
||
296 p
->deserialized_state
== PATH_RUNNING
)
297 path_enter_waiting(p
, true, true, false);
299 path_set_state(p
, p
->deserialized_state
);
305 static void path_enter_dead(Path
*p
, bool success
) {
311 path_set_state(p
, p
->failure
? PATH_FAILED
: PATH_DEAD
);
314 static void path_enter_running(Path
*p
) {
319 dbus_error_init(&error
);
321 /* Don't start job if we are supposed to go down */
322 if (p
->meta
.job
&& p
->meta
.job
->type
== JOB_STOP
)
325 if ((r
= manager_add_job(p
->meta
.manager
, JOB_START
, p
->unit
, JOB_REPLACE
, true, &error
, NULL
)) < 0)
328 p
->inotify_triggered
= false;
330 if ((r
= path_watch(p
)) < 0)
333 path_set_state(p
, PATH_RUNNING
);
337 log_warning("%s failed to queue unit startup job: %s", p
->meta
.id
, bus_error(&error
, r
));
338 path_enter_dead(p
, false);
340 dbus_error_free(&error
);
344 static void path_enter_waiting(Path
*p
, bool initial
, bool recheck
, bool skip_watch
) {
352 LIST_FOREACH(spec
, s
, p
->specs
) {
357 good
= access(s
->path
, F_OK
) >= 0;
360 case PATH_DIRECTORY_NOT_EMPTY
: {
363 k
= dir_is_empty(s
->path
);
364 good
= !(k
== -ENOENT
|| k
> 0);
371 b
= access(s
->path
, F_OK
) >= 0;
372 good
= !initial
&& b
!= s
->previous_exists
;
373 s
->previous_exists
= b
;
386 log_debug("%s got triggered.", p
->meta
.id
);
387 path_enter_running(p
);
393 if ((r
= path_watch(p
)) < 0)
396 /* Hmm, so now we have created inotify watches, but the file
397 * might have appeared/been removed by now, so we must
399 path_enter_waiting(p
, false, true, true);
403 path_set_state(p
, PATH_WAITING
);
407 log_warning("%s failed to enter waiting state: %s", p
->meta
.id
, strerror(-r
));
408 path_enter_dead(p
, false);
411 static int path_start(Unit
*u
) {
415 assert(p
->state
== PATH_DEAD
|| p
->state
== PATH_FAILED
);
417 if (p
->unit
->meta
.load_state
!= UNIT_LOADED
)
421 path_enter_waiting(p
, true, true, false);
426 static int path_stop(Unit
*u
) {
430 assert(p
->state
== PATH_WAITING
|| p
->state
== PATH_RUNNING
);
432 path_enter_dead(p
, true);
436 static int path_serialize(Unit
*u
, FILE *f
, FDSet
*fds
) {
443 unit_serialize_item(u
, f
, "state", path_state_to_string(p
->state
));
448 static int path_deserialize_item(Unit
*u
, const char *key
, const char *value
, FDSet
*fds
) {
456 if (streq(key
, "state")) {
459 if ((state
= path_state_from_string(value
)) < 0)
460 log_debug("Failed to parse state value %s", value
);
462 p
->deserialized_state
= state
;
464 log_debug("Unknown serialization key '%s'", key
);
469 static UnitActiveState
path_active_state(Unit
*u
) {
472 return state_translation_table
[PATH(u
)->state
];
475 static const char *path_sub_state_to_string(Unit
*u
) {
478 return path_state_to_string(PATH(u
)->state
);
481 static void path_fd_event(Unit
*u
, int fd
, uint32_t events
, Watch
*w
) {
486 struct inotify_event
*e
;
493 if (p
->state
!= PATH_WAITING
&&
494 p
->state
!= PATH_RUNNING
)
497 /* log_debug("inotify wakeup on %s.", u->meta.id); */
499 if (events
!= EPOLLIN
) {
500 log_error("Got Invalid poll event on inotify.");
504 LIST_FOREACH(spec
, s
, p
->specs
)
505 if (s
->inotify_fd
== fd
)
509 log_error("Got event on unknown fd.");
513 if (ioctl(fd
, FIONREAD
, &l
) < 0) {
514 log_error("FIONREAD failed: %s", strerror(errno
));
518 if (!(buf
= malloc(l
))) {
519 log_error("Failed to allocate buffer: %s", strerror(-ENOMEM
));
523 if ((k
= read(fd
, buf
, l
)) < 0) {
524 log_error("Failed to read inotify event: %s", strerror(-errno
));
528 /* If we are already running, then remember that one event was
529 * dispatched so that we restart the service only if something
530 * actually changed on disk */
531 p
->inotify_triggered
= true;
533 e
= (struct inotify_event
*) buf
;
539 if (s
->type
== PATH_CHANGED
&& s
->primary_wd
== e
->wd
)
542 step
= sizeof(struct inotify_event
) + e
->len
;
543 assert(step
<= (size_t) k
);
545 e
= (struct inotify_event
*) ((uint8_t*) e
+ step
);
550 path_enter_running(p
);
552 path_enter_waiting(p
, false, true, false);
560 path_enter_dead(p
, false);
563 void path_unit_notify(Unit
*u
, UnitActiveState new_state
) {
568 if (u
->meta
.type
== UNIT_PATH
)
571 SET_FOREACH(n
, u
->meta
.names
, i
) {
576 if (!(k
= unit_name_change_suffix(n
, ".path"))) {
581 t
= manager_get_unit(u
->meta
.manager
, k
);
587 if (t
->meta
.load_state
!= UNIT_LOADED
)
595 if (p
->state
== PATH_RUNNING
&& new_state
== UNIT_INACTIVE
) {
596 log_debug("%s got notified about unit deactivation.", p
->meta
.id
);
598 /* Hmm, so inotify was triggered since the
599 * last activation, so I guess we need to
600 * recheck what is going on. */
601 path_enter_waiting(p
, false, p
->inotify_triggered
, false);
608 log_error("Failed find path unit: %s", strerror(-r
));
611 static void path_reset_failed(Unit
*u
) {
616 if (p
->state
== PATH_FAILED
)
617 path_set_state(p
, PATH_DEAD
);
622 static const char* const path_state_table
[_PATH_STATE_MAX
] = {
623 [PATH_DEAD
] = "dead",
624 [PATH_WAITING
] = "waiting",
625 [PATH_RUNNING
] = "running",
626 [PATH_FAILED
] = "failed"
629 DEFINE_STRING_TABLE_LOOKUP(path_state
, PathState
);
631 static const char* const path_type_table
[_PATH_TYPE_MAX
] = {
632 [PATH_EXISTS
] = "PathExists",
633 [PATH_CHANGED
] = "PathChanged",
634 [PATH_DIRECTORY_NOT_EMPTY
] = "DirectoryNotEmpty"
637 DEFINE_STRING_TABLE_LOOKUP(path_type
, PathType
);
639 const UnitVTable path_vtable
= {
645 .coldplug
= path_coldplug
,
652 .serialize
= path_serialize
,
653 .deserialize_item
= path_deserialize_item
,
655 .active_state
= path_active_state
,
656 .sub_state_to_string
= path_sub_state_to_string
,
658 .fd_event
= path_fd_event
,
660 .reset_failed
= path_reset_failed
,
662 .bus_interface
= "org.freedesktop.systemd1.Path",
663 .bus_message_handler
= bus_path_message_handler