diff options
Diffstat (limited to 'src/core/path.c')
| -rw-r--r-- | src/core/path.c | 788 |
1 files changed, 0 insertions, 788 deletions
diff --git a/src/core/path.c b/src/core/path.c deleted file mode 100644 index 83f794be89..0000000000 --- a/src/core/path.c +++ /dev/null @@ -1,788 +0,0 @@ -/*** - This file is part of systemd. - - Copyright 2010 Lennart Poettering - - systemd is free software; you can redistribute it and/or modify it - under the terms of the GNU Lesser General Public License as published by - the Free Software Foundation; either version 2.1 of the License, or - (at your option) any later version. - - systemd is distributed in the hope that it will be useful, but - WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public License - along with systemd; If not, see <http://www.gnu.org/licenses/>. -***/ - -#include <errno.h> -#include <sys/epoll.h> -#include <sys/inotify.h> -#include <unistd.h> - -#include "bus-error.h" -#include "bus-util.h" -#include "dbus-path.h" -#include "fd-util.h" -#include "fs-util.h" -#include "glob-util.h" -#include "macro.h" -#include "mkdir.h" -#include "path.h" -#include "special.h" -#include "stat-util.h" -#include "string-table.h" -#include "string-util.h" -#include "unit-name.h" -#include "unit.h" - -static const UnitActiveState state_translation_table[_PATH_STATE_MAX] = { - [PATH_DEAD] = UNIT_INACTIVE, - [PATH_WAITING] = UNIT_ACTIVE, - [PATH_RUNNING] = UNIT_ACTIVE, - [PATH_FAILED] = UNIT_FAILED -}; - -static int path_dispatch_io(sd_event_source *source, int fd, uint32_t revents, void *userdata); - -int path_spec_watch(PathSpec *s, sd_event_io_handler_t handler) { - - static const int flags_table[_PATH_TYPE_MAX] = { - [PATH_EXISTS] = IN_DELETE_SELF|IN_MOVE_SELF|IN_ATTRIB, - [PATH_EXISTS_GLOB] = IN_DELETE_SELF|IN_MOVE_SELF|IN_ATTRIB, - [PATH_CHANGED] = IN_DELETE_SELF|IN_MOVE_SELF|IN_ATTRIB|IN_CLOSE_WRITE|IN_CREATE|IN_DELETE|IN_MOVED_FROM|IN_MOVED_TO, - [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, - [PATH_DIRECTORY_NOT_EMPTY] = IN_DELETE_SELF|IN_MOVE_SELF|IN_ATTRIB|IN_CREATE|IN_MOVED_TO - }; - - bool exists = false; - char *slash, *oldslash = NULL; - int r; - - assert(s); - assert(s->unit); - assert(handler); - - path_spec_unwatch(s); - - s->inotify_fd = inotify_init1(IN_NONBLOCK|IN_CLOEXEC); - if (s->inotify_fd < 0) { - r = -errno; - goto fail; - } - - r = sd_event_add_io(s->unit->manager->event, &s->event_source, s->inotify_fd, EPOLLIN, handler, s); - if (r < 0) - goto fail; - - (void) sd_event_source_set_description(s->event_source, "path"); - - /* This assumes the path was passed through path_kill_slashes()! */ - - for (slash = strchr(s->path, '/'); ; slash = strchr(slash+1, '/')) { - char *cut = NULL; - int flags; - char tmp; - - if (slash) { - cut = slash + (slash == s->path); - tmp = *cut; - *cut = '\0'; - - flags = IN_MOVE_SELF | IN_DELETE_SELF | IN_ATTRIB | IN_CREATE | IN_MOVED_TO; - } else - flags = flags_table[s->type]; - - r = inotify_add_watch(s->inotify_fd, s->path, flags); - if (r < 0) { - if (errno == EACCES || errno == ENOENT) { - if (cut) - *cut = tmp; - break; - } - - r = log_warning_errno(errno, "Failed to add watch on %s: %s", s->path, errno == ENOSPC ? "too many watches" : strerror(-r)); - if (cut) - *cut = tmp; - goto fail; - } else { - exists = true; - - /* Path exists, we don't need to watch parent too closely. */ - if (oldslash) { - char *cut2 = oldslash + (oldslash == s->path); - char tmp2 = *cut2; - *cut2 = '\0'; - - (void) inotify_add_watch(s->inotify_fd, s->path, IN_MOVE_SELF); - /* Error is ignored, the worst can happen is we get spurious events. */ - - *cut2 = tmp2; - } - } - - if (cut) - *cut = tmp; - - if (slash) - oldslash = slash; - else { - /* whole path has been iterated over */ - s->primary_wd = r; - break; - } - } - - if (!exists) { - r = log_error_errno(errno, "Failed to add watch on any of the components of %s: %m", s->path); - /* either EACCESS or ENOENT */ - goto fail; - } - - return 0; - -fail: - path_spec_unwatch(s); - return r; -} - -void path_spec_unwatch(PathSpec *s) { - assert(s); - - s->event_source = sd_event_source_unref(s->event_source); - s->inotify_fd = safe_close(s->inotify_fd); -} - -int path_spec_fd_event(PathSpec *s, uint32_t revents) { - union inotify_event_buffer buffer; - struct inotify_event *e; - ssize_t l; - int r = 0; - - if (revents != EPOLLIN) { - log_error("Got invalid poll event on inotify."); - return -EINVAL; - } - - l = read(s->inotify_fd, &buffer, sizeof(buffer)); - if (l < 0) { - if (errno == EAGAIN || errno == EINTR) - return 0; - - return log_error_errno(errno, "Failed to read inotify event: %m"); - } - - FOREACH_INOTIFY_EVENT(e, buffer, l) { - if ((s->type == PATH_CHANGED || s->type == PATH_MODIFIED) && - s->primary_wd == e->wd) - r = 1; - } - - return r; -} - -static bool path_spec_check_good(PathSpec *s, bool initial) { - bool good = false; - - switch (s->type) { - - case PATH_EXISTS: - good = access(s->path, F_OK) >= 0; - break; - - case PATH_EXISTS_GLOB: - good = glob_exists(s->path) > 0; - break; - - case PATH_DIRECTORY_NOT_EMPTY: { - int k; - - k = dir_is_empty(s->path); - good = !(k == -ENOENT || k > 0); - break; - } - - case PATH_CHANGED: - case PATH_MODIFIED: { - bool b; - - b = access(s->path, F_OK) >= 0; - good = !initial && b != s->previous_exists; - s->previous_exists = b; - break; - } - - default: - ; - } - - return good; -} - -static void path_spec_mkdir(PathSpec *s, mode_t mode) { - int r; - - if (s->type == PATH_EXISTS || s->type == PATH_EXISTS_GLOB) - return; - - r = mkdir_p_label(s->path, mode); - if (r < 0) - log_warning_errno(r, "mkdir(%s) failed: %m", s->path); -} - -static void path_spec_dump(PathSpec *s, FILE *f, const char *prefix) { - fprintf(f, - "%s%s: %s\n", - prefix, - path_type_to_string(s->type), - s->path); -} - -void path_spec_done(PathSpec *s) { - assert(s); - assert(s->inotify_fd == -1); - - free(s->path); -} - -static void path_init(Unit *u) { - Path *p = PATH(u); - - assert(u); - assert(u->load_state == UNIT_STUB); - - p->directory_mode = 0755; -} - -void path_free_specs(Path *p) { - PathSpec *s; - - assert(p); - - while ((s = p->specs)) { - path_spec_unwatch(s); - LIST_REMOVE(spec, p->specs, s); - path_spec_done(s); - free(s); - } -} - -static void path_done(Unit *u) { - Path *p = PATH(u); - - assert(p); - - path_free_specs(p); -} - -static int path_add_mount_links(Path *p) { - PathSpec *s; - int r; - - assert(p); - - LIST_FOREACH(spec, s, p->specs) { - r = unit_require_mounts_for(UNIT(p), s->path); - if (r < 0) - return r; - } - - return 0; -} - -static int path_verify(Path *p) { - assert(p); - - if (UNIT(p)->load_state != UNIT_LOADED) - return 0; - - if (!p->specs) { - log_unit_error(UNIT(p), "Path unit lacks path setting. Refusing."); - return -EINVAL; - } - - return 0; -} - -static int path_add_default_dependencies(Path *p) { - int r; - - assert(p); - - if (!UNIT(p)->default_dependencies) - return 0; - - r = unit_add_dependency_by_name(UNIT(p), UNIT_BEFORE, SPECIAL_PATHS_TARGET, NULL, true); - if (r < 0) - return r; - - if (MANAGER_IS_SYSTEM(UNIT(p)->manager)) { - r = unit_add_two_dependencies_by_name(UNIT(p), UNIT_AFTER, UNIT_REQUIRES, SPECIAL_SYSINIT_TARGET, NULL, true); - if (r < 0) - return r; - } - - return unit_add_two_dependencies_by_name(UNIT(p), UNIT_BEFORE, UNIT_CONFLICTS, SPECIAL_SHUTDOWN_TARGET, NULL, true); -} - -static int path_load(Unit *u) { - Path *p = PATH(u); - int r; - - assert(u); - assert(u->load_state == UNIT_STUB); - - r = unit_load_fragment_and_dropin(u); - if (r < 0) - return r; - - if (u->load_state == UNIT_LOADED) { - - if (set_isempty(u->dependencies[UNIT_TRIGGERS])) { - Unit *x; - - r = unit_load_related_unit(u, ".service", &x); - if (r < 0) - return r; - - r = unit_add_two_dependencies(u, UNIT_BEFORE, UNIT_TRIGGERS, x, true); - if (r < 0) - return r; - } - - r = path_add_mount_links(p); - if (r < 0) - return r; - - r = path_add_default_dependencies(p); - if (r < 0) - return r; - } - - return path_verify(p); -} - -static void path_dump(Unit *u, FILE *f, const char *prefix) { - Path *p = PATH(u); - Unit *trigger; - PathSpec *s; - - assert(p); - assert(f); - - trigger = UNIT_TRIGGER(u); - - fprintf(f, - "%sPath State: %s\n" - "%sResult: %s\n" - "%sUnit: %s\n" - "%sMakeDirectory: %s\n" - "%sDirectoryMode: %04o\n", - prefix, path_state_to_string(p->state), - prefix, path_result_to_string(p->result), - prefix, trigger ? trigger->id : "n/a", - prefix, yes_no(p->make_directory), - prefix, p->directory_mode); - - LIST_FOREACH(spec, s, p->specs) - path_spec_dump(s, f, prefix); -} - -static void path_unwatch(Path *p) { - PathSpec *s; - - assert(p); - - LIST_FOREACH(spec, s, p->specs) - path_spec_unwatch(s); -} - -static int path_watch(Path *p) { - int r; - PathSpec *s; - - assert(p); - - LIST_FOREACH(spec, s, p->specs) { - r = path_spec_watch(s, path_dispatch_io); - if (r < 0) - return r; - } - - return 0; -} - -static void path_set_state(Path *p, PathState state) { - PathState old_state; - assert(p); - - old_state = p->state; - p->state = state; - - if (state != PATH_WAITING && - (state != PATH_RUNNING || p->inotify_triggered)) - path_unwatch(p); - - if (state != old_state) - log_unit_debug(UNIT(p), "Changed %s -> %s", path_state_to_string(old_state), path_state_to_string(state)); - - unit_notify(UNIT(p), state_translation_table[old_state], state_translation_table[state], true); -} - -static void path_enter_waiting(Path *p, bool initial, bool recheck); - -static int path_coldplug(Unit *u) { - Path *p = PATH(u); - - assert(p); - assert(p->state == PATH_DEAD); - - if (p->deserialized_state != p->state) { - - if (p->deserialized_state == PATH_WAITING || - p->deserialized_state == PATH_RUNNING) - path_enter_waiting(p, true, true); - else - path_set_state(p, p->deserialized_state); - } - - return 0; -} - -static void path_enter_dead(Path *p, PathResult f) { - assert(p); - - if (p->result == PATH_SUCCESS) - p->result = f; - - path_set_state(p, p->result != PATH_SUCCESS ? PATH_FAILED : PATH_DEAD); -} - -static void path_enter_running(Path *p) { - _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL; - Unit *trigger; - int r; - - assert(p); - - /* Don't start job if we are supposed to go down */ - if (unit_stop_pending(UNIT(p))) - return; - - trigger = UNIT_TRIGGER(UNIT(p)); - if (!trigger) { - log_unit_error(UNIT(p), "Unit to trigger vanished."); - path_enter_dead(p, PATH_FAILURE_RESOURCES); - return; - } - - r = manager_add_job(UNIT(p)->manager, JOB_START, trigger, JOB_REPLACE, &error, NULL); - if (r < 0) - goto fail; - - p->inotify_triggered = false; - - r = path_watch(p); - if (r < 0) - goto fail; - - path_set_state(p, PATH_RUNNING); - return; - -fail: - log_unit_warning(UNIT(p), "Failed to queue unit startup job: %s", bus_error_message(&error, r)); - path_enter_dead(p, PATH_FAILURE_RESOURCES); -} - -static bool path_check_good(Path *p, bool initial) { - PathSpec *s; - bool good = false; - - assert(p); - - LIST_FOREACH(spec, s, p->specs) { - good = path_spec_check_good(s, initial); - - if (good) - break; - } - - return good; -} - -static void path_enter_waiting(Path *p, bool initial, bool recheck) { - int r; - - if (recheck) - if (path_check_good(p, initial)) { - log_unit_debug(UNIT(p), "Got triggered."); - path_enter_running(p); - return; - } - - r = path_watch(p); - if (r < 0) - goto fail; - - /* Hmm, so now we have created inotify watches, but the file - * might have appeared/been removed by now, so we must - * recheck */ - - if (recheck) - if (path_check_good(p, false)) { - log_unit_debug(UNIT(p), "Got triggered."); - path_enter_running(p); - return; - } - - path_set_state(p, PATH_WAITING); - return; - -fail: - log_unit_warning_errno(UNIT(p), r, "Failed to enter waiting state: %m"); - path_enter_dead(p, PATH_FAILURE_RESOURCES); -} - -static void path_mkdir(Path *p) { - PathSpec *s; - - assert(p); - - if (!p->make_directory) - return; - - LIST_FOREACH(spec, s, p->specs) - path_spec_mkdir(s, p->directory_mode); -} - -static int path_start(Unit *u) { - Path *p = PATH(u); - Unit *trigger; - int r; - - assert(p); - assert(p->state == PATH_DEAD || p->state == PATH_FAILED); - - trigger = UNIT_TRIGGER(u); - if (!trigger || trigger->load_state != UNIT_LOADED) { - log_unit_error(u, "Refusing to start, unit to trigger not loaded."); - return -ENOENT; - } - - r = unit_start_limit_test(u); - if (r < 0) { - path_enter_dead(p, PATH_FAILURE_START_LIMIT_HIT); - return r; - } - - r = unit_acquire_invocation_id(u); - if (r < 0) - return r; - - path_mkdir(p); - - p->result = PATH_SUCCESS; - path_enter_waiting(p, true, true); - - return 1; -} - -static int path_stop(Unit *u) { - Path *p = PATH(u); - - assert(p); - assert(p->state == PATH_WAITING || p->state == PATH_RUNNING); - - path_enter_dead(p, PATH_SUCCESS); - return 1; -} - -static int path_serialize(Unit *u, FILE *f, FDSet *fds) { - Path *p = PATH(u); - - assert(u); - assert(f); - assert(fds); - - unit_serialize_item(u, f, "state", path_state_to_string(p->state)); - unit_serialize_item(u, f, "result", path_result_to_string(p->result)); - - return 0; -} - -static int path_deserialize_item(Unit *u, const char *key, const char *value, FDSet *fds) { - Path *p = PATH(u); - - assert(u); - assert(key); - assert(value); - assert(fds); - - if (streq(key, "state")) { - PathState state; - - state = path_state_from_string(value); - if (state < 0) - log_unit_debug(u, "Failed to parse state value: %s", value); - else - p->deserialized_state = state; - - } else if (streq(key, "result")) { - PathResult f; - - f = path_result_from_string(value); - if (f < 0) - log_unit_debug(u, "Failed to parse result value: %s", value); - else if (f != PATH_SUCCESS) - p->result = f; - - } else - log_unit_debug(u, "Unknown serialization key: %s", key); - - return 0; -} - -_pure_ static UnitActiveState path_active_state(Unit *u) { - assert(u); - - return state_translation_table[PATH(u)->state]; -} - -_pure_ static const char *path_sub_state_to_string(Unit *u) { - assert(u); - - return path_state_to_string(PATH(u)->state); -} - -static int path_dispatch_io(sd_event_source *source, int fd, uint32_t revents, void *userdata) { - PathSpec *s = userdata; - Path *p; - int changed; - - assert(s); - assert(s->unit); - assert(fd >= 0); - - p = PATH(s->unit); - - if (p->state != PATH_WAITING && - p->state != PATH_RUNNING) - return 0; - - /* log_debug("inotify wakeup on %s.", u->id); */ - - LIST_FOREACH(spec, s, p->specs) - if (path_spec_owns_inotify_fd(s, fd)) - break; - - if (!s) { - log_error("Got event on unknown fd."); - goto fail; - } - - changed = path_spec_fd_event(s, revents); - if (changed < 0) - goto fail; - - /* If we are already running, then remember that one event was - * dispatched so that we restart the service only if something - * actually changed on disk */ - p->inotify_triggered = true; - - if (changed) - path_enter_running(p); - else - path_enter_waiting(p, false, true); - - return 0; - -fail: - path_enter_dead(p, PATH_FAILURE_RESOURCES); - return 0; -} - -static void path_trigger_notify(Unit *u, Unit *other) { - Path *p = PATH(u); - - assert(u); - assert(other); - - /* Invoked whenever the unit we trigger changes state or gains - * or loses a job */ - - if (other->load_state != UNIT_LOADED) - return; - - if (p->state == PATH_RUNNING && - UNIT_IS_INACTIVE_OR_FAILED(unit_active_state(other))) { - log_unit_debug(UNIT(p), "Got notified about unit deactivation."); - - /* Hmm, so inotify was triggered since the - * last activation, so I guess we need to - * recheck what is going on. */ - path_enter_waiting(p, false, p->inotify_triggered); - } -} - -static void path_reset_failed(Unit *u) { - Path *p = PATH(u); - - assert(p); - - if (p->state == PATH_FAILED) - path_set_state(p, PATH_DEAD); - - p->result = PATH_SUCCESS; -} - -static const char* const path_type_table[_PATH_TYPE_MAX] = { - [PATH_EXISTS] = "PathExists", - [PATH_EXISTS_GLOB] = "PathExistsGlob", - [PATH_DIRECTORY_NOT_EMPTY] = "DirectoryNotEmpty", - [PATH_CHANGED] = "PathChanged", - [PATH_MODIFIED] = "PathModified", -}; - -DEFINE_STRING_TABLE_LOOKUP(path_type, PathType); - -static const char* const path_result_table[_PATH_RESULT_MAX] = { - [PATH_SUCCESS] = "success", - [PATH_FAILURE_RESOURCES] = "resources", - [PATH_FAILURE_START_LIMIT_HIT] = "start-limit-hit", -}; - -DEFINE_STRING_TABLE_LOOKUP(path_result, PathResult); - -const UnitVTable path_vtable = { - .object_size = sizeof(Path), - - .sections = - "Unit\0" - "Path\0" - "Install\0", - - .init = path_init, - .done = path_done, - .load = path_load, - - .coldplug = path_coldplug, - - .dump = path_dump, - - .start = path_start, - .stop = path_stop, - - .serialize = path_serialize, - .deserialize_item = path_deserialize_item, - - .active_state = path_active_state, - .sub_state_to_string = path_sub_state_to_string, - - .trigger_notify = path_trigger_notify, - - .reset_failed = path_reset_failed, - - .bus_vtable = bus_path_vtable -}; |