/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ /*** 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 General Public License as published by the Free Software Foundation; either version 2 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 General Public License for more details. You should have received a copy of the GNU General Public License along with systemd; If not, see . ***/ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef HAVE_AUDIT #include #endif #include "manager.h" #include "hashmap.h" #include "macro.h" #include "strv.h" #include "log.h" #include "util.h" #include "ratelimit.h" #include "cgroup.h" #include "mount-setup.h" #include "unit-name.h" #include "dbus-unit.h" #include "dbus-job.h" #include "missing.h" #include "path-lookup.h" #include "special.h" #include "bus-errors.h" #include "exit-status.h" /* As soon as 16 units are in our GC queue, make sure to run a gc sweep */ #define GC_QUEUE_ENTRIES_MAX 16 /* As soon as 5s passed since a unit was added to our GC queue, make sure to run a gc sweep */ #define GC_QUEUE_USEC_MAX (10*USEC_PER_SEC) /* Where clients shall send notification messages to */ #define NOTIFY_SOCKET "/org/freedesktop/systemd1/notify" static int manager_setup_notify(Manager *m) { union { struct sockaddr sa; struct sockaddr_un un; } sa; struct epoll_event ev; int one = 1; assert(m); m->notify_watch.type = WATCH_NOTIFY; if ((m->notify_watch.fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0)) < 0) { log_error("Failed to allocate notification socket: %m"); return -errno; } zero(sa); sa.sa.sa_family = AF_UNIX; if (getpid() != 1) snprintf(sa.un.sun_path+1, sizeof(sa.un.sun_path)-1, NOTIFY_SOCKET "/%llu", random_ull()); else strncpy(sa.un.sun_path+1, NOTIFY_SOCKET, sizeof(sa.un.sun_path)-1); if (bind(m->notify_watch.fd, &sa.sa, offsetof(struct sockaddr_un, sun_path) + 1 + strlen(sa.un.sun_path+1)) < 0) { log_error("bind() failed: %m"); return -errno; } if (setsockopt(m->notify_watch.fd, SOL_SOCKET, SO_PASSCRED, &one, sizeof(one)) < 0) { log_error("SO_PASSCRED failed: %m"); return -errno; } zero(ev); ev.events = EPOLLIN; ev.data.ptr = &m->notify_watch; if (epoll_ctl(m->epoll_fd, EPOLL_CTL_ADD, m->notify_watch.fd, &ev) < 0) return -errno; if (!(m->notify_socket = strdup(sa.un.sun_path+1))) return -ENOMEM; log_debug("Using notification socket %s", m->notify_socket); return 0; } static int enable_special_signals(Manager *m) { char fd; assert(m); /* Enable that we get SIGINT on control-alt-del */ if (reboot(RB_DISABLE_CAD) < 0) log_warning("Failed to enable ctrl-alt-del handling: %m"); if ((fd = open_terminal("/dev/tty0", O_RDWR|O_NOCTTY)) < 0) log_warning("Failed to open /dev/tty0: %m"); else { /* Enable that we get SIGWINCH on kbrequest */ if (ioctl(fd, KDSIGACCEPT, SIGWINCH) < 0) log_warning("Failed to enable kbrequest handling: %s", strerror(errno)); close_nointr_nofail(fd); } return 0; } static int manager_setup_signals(Manager *m) { sigset_t mask; struct epoll_event ev; struct sigaction sa; assert(m); /* We are not interested in SIGSTOP and friends. */ zero(sa); sa.sa_handler = SIG_DFL; sa.sa_flags = SA_NOCLDSTOP|SA_RESTART; assert_se(sigaction(SIGCHLD, &sa, NULL) == 0); assert_se(sigemptyset(&mask) == 0); sigset_add_many(&mask, SIGCHLD, /* Child died */ SIGTERM, /* Reexecute daemon */ SIGHUP, /* Reload configuration */ SIGUSR1, /* systemd/upstart: reconnect to D-Bus */ SIGUSR2, /* systemd: dump status */ SIGINT, /* Kernel sends us this on control-alt-del */ SIGWINCH, /* Kernel sends us this on kbrequest (alt-arrowup) */ SIGPWR, /* Some kernel drivers and upsd send us this on power failure */ SIGRTMIN+0, /* systemd: start default.target */ SIGRTMIN+1, /* systemd: isolate rescue.target */ SIGRTMIN+2, /* systemd: isolate emergency.target */ SIGRTMIN+3, /* systemd: start halt.target */ SIGRTMIN+4, /* systemd: start poweroff.target */ SIGRTMIN+5, /* systemd: start reboot.target */ SIGRTMIN+6, /* systemd: start kexec.target */ SIGRTMIN+13, /* systemd: Immediate halt */ SIGRTMIN+14, /* systemd: Immediate poweroff */ SIGRTMIN+15, /* systemd: Immediate reboot */ SIGRTMIN+16, /* systemd: Immediate kexec */ -1); assert_se(sigprocmask(SIG_SETMASK, &mask, NULL) == 0); m->signal_watch.type = WATCH_SIGNAL; if ((m->signal_watch.fd = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC)) < 0) return -errno; zero(ev); ev.events = EPOLLIN; ev.data.ptr = &m->signal_watch; if (epoll_ctl(m->epoll_fd, EPOLL_CTL_ADD, m->signal_watch.fd, &ev) < 0) return -errno; if (m->running_as == MANAGER_SYSTEM) return enable_special_signals(m); return 0; } int manager_new(ManagerRunningAs running_as, Manager **_m) { Manager *m; int r = -ENOMEM; assert(_m); assert(running_as >= 0); assert(running_as < _MANAGER_RUNNING_AS_MAX); if (!(m = new0(Manager, 1))) return -ENOMEM; dual_timestamp_get(&m->startup_timestamp); m->running_as = running_as; m->name_data_slot = m->subscribed_data_slot = -1; m->exit_code = _MANAGER_EXIT_CODE_INVALID; m->pin_cgroupfs_fd = -1; #ifdef HAVE_AUDIT m->audit_fd = -1; #endif m->signal_watch.fd = m->mount_watch.fd = m->udev_watch.fd = m->epoll_fd = m->dev_autofs_fd = m->swap_watch.fd = -1; m->current_job_id = 1; /* start as id #1, so that we can leave #0 around as "null-like" value */ if (!(m->environment = strv_copy(environ))) goto fail; if (!(m->units = hashmap_new(string_hash_func, string_compare_func))) goto fail; if (!(m->jobs = hashmap_new(trivial_hash_func, trivial_compare_func))) goto fail; if (!(m->transaction_jobs = hashmap_new(trivial_hash_func, trivial_compare_func))) goto fail; if (!(m->watch_pids = hashmap_new(trivial_hash_func, trivial_compare_func))) goto fail; if (!(m->cgroup_bondings = hashmap_new(string_hash_func, string_compare_func))) goto fail; if (!(m->watch_bus = hashmap_new(string_hash_func, string_compare_func))) goto fail; if ((m->epoll_fd = epoll_create1(EPOLL_CLOEXEC)) < 0) goto fail; if ((r = lookup_paths_init(&m->lookup_paths, m->running_as)) < 0) goto fail; if ((r = manager_setup_signals(m)) < 0) goto fail; if ((r = manager_setup_cgroup(m)) < 0) goto fail; if ((r = manager_setup_notify(m)) < 0) goto fail; /* Try to connect to the busses, if possible. */ if ((r = bus_init(m)) < 0) goto fail; #ifdef HAVE_AUDIT if ((m->audit_fd = audit_open()) < 0) log_error("Failed to connect to audit log: %m"); #endif *_m = m; return 0; fail: manager_free(m); return r; } static unsigned manager_dispatch_cleanup_queue(Manager *m) { Meta *meta; unsigned n = 0; assert(m); while ((meta = m->cleanup_queue)) { assert(meta->in_cleanup_queue); unit_free((Unit*) meta); n++; } return n; } enum { GC_OFFSET_IN_PATH, /* This one is on the path we were travelling */ GC_OFFSET_UNSURE, /* No clue */ GC_OFFSET_GOOD, /* We still need this unit */ GC_OFFSET_BAD, /* We don't need this unit anymore */ _GC_OFFSET_MAX }; static void unit_gc_sweep(Unit *u, unsigned gc_marker) { Iterator i; Unit *other; bool is_bad; assert(u); if (u->meta.gc_marker == gc_marker + GC_OFFSET_GOOD || u->meta.gc_marker == gc_marker + GC_OFFSET_BAD || u->meta.gc_marker == gc_marker + GC_OFFSET_IN_PATH) return; if (u->meta.in_cleanup_queue) goto bad; if (unit_check_gc(u)) goto good; u->meta.gc_marker = gc_marker + GC_OFFSET_IN_PATH; is_bad = true; SET_FOREACH(other, u->meta.dependencies[UNIT_REFERENCED_BY], i) { unit_gc_sweep(other, gc_marker); if (other->meta.gc_marker == gc_marker + GC_OFFSET_GOOD) goto good; if (other->meta.gc_marker != gc_marker + GC_OFFSET_BAD) is_bad = false; } if (is_bad) goto bad; /* We were unable to find anything out about this entry, so * let's investigate it later */ u->meta.gc_marker = gc_marker + GC_OFFSET_UNSURE; unit_add_to_gc_queue(u); return; bad: /* We definitely know that this one is not useful anymore, so * let's mark it for deletion */ u->meta.gc_marker = gc_marker + GC_OFFSET_BAD; unit_add_to_cleanup_queue(u); return; good: u->meta.gc_marker = gc_marker + GC_OFFSET_GOOD; } static unsigned manager_dispatch_gc_queue(Manager *m) { Meta *meta; unsigned n = 0; unsigned gc_marker; assert(m); if ((m->n_in_gc_queue < GC_QUEUE_ENTRIES_MAX) && (m->gc_queue_timestamp <= 0 || (m->gc_queue_timestamp + GC_QUEUE_USEC_MAX) > now(CLOCK_MONOTONIC))) return 0; log_debug("Running GC..."); m->gc_marker += _GC_OFFSET_MAX; if (m->gc_marker + _GC_OFFSET_MAX <= _GC_OFFSET_MAX) m->gc_marker = 1; gc_marker = m->gc_marker; while ((meta = m->gc_queue)) { assert(meta->in_gc_queue); unit_gc_sweep((Unit*) meta, gc_marker); LIST_REMOVE(Meta, gc_queue, m->gc_queue, meta); meta->in_gc_queue = false; n++; if (meta->gc_marker == gc_marker + GC_OFFSET_BAD || meta->gc_marker == gc_marker + GC_OFFSET_UNSURE) { log_debug("Collecting %s", meta->id); meta->gc_marker = gc_marker + GC_OFFSET_BAD; unit_add_to_cleanup_queue((Unit*) meta); } } m->n_in_gc_queue = 0; m->gc_queue_timestamp = 0; return n; } static void manager_clear_jobs_and_units(Manager *m) { Job *j; Unit *u; assert(m); while ((j = hashmap_first(m->transaction_jobs))) job_free(j); while ((u = hashmap_first(m->units))) unit_free(u); manager_dispatch_cleanup_queue(m); assert(!m->load_queue); assert(!m->run_queue); assert(!m->dbus_unit_queue); assert(!m->dbus_job_queue); assert(!m->cleanup_queue); assert(!m->gc_queue); assert(hashmap_isempty(m->transaction_jobs)); assert(hashmap_isempty(m->jobs)); assert(hashmap_isempty(m->units)); } void manager_free(Manager *m) { UnitType c; assert(m); manager_clear_jobs_and_units(m); for (c = 0; c < _UNIT_TYPE_MAX; c++) if (unit_vtable[c]->shutdown) unit_vtable[c]->shutdown(m); /* If we reexecute ourselves, we keep the root cgroup * around */ manager_shutdown_cgroup(m, m->exit_code != MANAGER_REEXECUTE); manager_undo_generators(m); bus_done(m); hashmap_free(m->units); hashmap_free(m->jobs); hashmap_free(m->transaction_jobs); hashmap_free(m->watch_pids); hashmap_free(m->watch_bus); if (m->epoll_fd >= 0) close_nointr_nofail(m->epoll_fd); if (m->signal_watch.fd >= 0) close_nointr_nofail(m->signal_watch.fd); if (m->notify_watch.fd >= 0) close_nointr_nofail(m->notify_watch.fd); #ifdef HAVE_AUDIT if (m->audit_fd >= 0) audit_close(m->audit_fd); #endif free(m->notify_socket); free(m->console); lookup_paths_free(&m->lookup_paths); strv_free(m->environment); hashmap_free(m->cgroup_bondings); set_free_free(m->unit_path_cache); free(m); } int manager_enumerate(Manager *m) { int r = 0, q; UnitType c; assert(m); /* Let's ask every type to load all units from disk/kernel * that it might know */ for (c = 0; c < _UNIT_TYPE_MAX; c++) if (unit_vtable[c]->enumerate) if ((q = unit_vtable[c]->enumerate(m)) < 0) r = q; manager_dispatch_load_queue(m); return r; } int manager_coldplug(Manager *m) { int r = 0, q; Iterator i; Unit *u; char *k; assert(m); /* Then, let's set up their initial state. */ HASHMAP_FOREACH_KEY(u, k, m->units, i) { /* ignore aliases */ if (u->meta.id != k) continue; if ((q = unit_coldplug(u)) < 0) r = q; } return r; } static void manager_build_unit_path_cache(Manager *m) { char **i; DIR *d = NULL; int r; assert(m); set_free_free(m->unit_path_cache); if (!(m->unit_path_cache = set_new(string_hash_func, string_compare_func))) { log_error("Failed to allocate unit path cache."); return; } /* This simply builds a list of files we know exist, so that * we don't always have to go to disk */ STRV_FOREACH(i, m->lookup_paths.unit_path) { struct dirent *de; if (!(d = opendir(*i))) { log_error("Failed to open directory: %m"); continue; } while ((de = readdir(d))) { char *p; if (ignore_file(de->d_name)) continue; if (asprintf(&p, "%s/%s", streq(*i, "/") ? "" : *i, de->d_name) < 0) { r = -ENOMEM; goto fail; } if ((r = set_put(m->unit_path_cache, p)) < 0) { free(p); goto fail; } } closedir(d); d = NULL; } return; fail: log_error("Failed to build unit path cache: %s", strerror(-r)); set_free_free(m->unit_path_cache); m->unit_path_cache = NULL; if (d) closedir(d); } int manager_startup(Manager *m, FILE *serialization, FDSet *fds) { int r, q; assert(m); manager_run_generators(m); manager_build_unit_path_cache(m); /* If we will deserialize make sure that during enumeration * this is already known, so we increase the counter here * already */ if (serialization) m->n_deserializing ++; /* First, enumerate what we can from all config files */ r = manager_enumerate(m); /* Second, deserialize if there is something to deserialize */ if (serialization) if ((q = manager_deserialize(m, serialization, fds)) < 0) r = q; /* Third, fire things up! */ if ((q = manager_coldplug(m)) < 0) r = q; if (serialization) { assert(m->n_deserializing > 0); m->n_deserializing --; } return r; } static void transaction_delete_job(Manager *m, Job *j, bool delete_dependencies) { assert(m); assert(j); /* Deletes one job from the transaction */ manager_transaction_unlink_job(m, j, delete_dependencies); if (!j->installed) job_free(j); } static void transaction_delete_unit(Manager *m, Unit *u) { Job *j; /* Deletes all jobs associated with a certain unit from the * transaction */ while ((j = hashmap_get(m->transaction_jobs, u))) transaction_delete_job(m, j, true); } static void transaction_clean_dependencies(Manager *m) { Iterator i; Job *j; assert(m); /* Drops all dependencies of all installed jobs */ HASHMAP_FOREACH(j, m->jobs, i) { while (j->subject_list) job_dependency_free(j->subject_list); while (j->object_list) job_dependency_free(j->object_list); } assert(!m->transaction_anchor); } static void transaction_abort(Manager *m) { Job *j; assert(m); while ((j = hashmap_first(m->transaction_jobs))) if (j->installed) transaction_delete_job(m, j, true); else job_free(j); assert(hashmap_isempty(m->transaction_jobs)); transaction_clean_dependencies(m); } static void transaction_find_jobs_that_matter_to_anchor(Manager *m, Job *j, unsigned generation) { JobDependency *l; assert(m); /* A recursive sweep through the graph that marks all units * that matter to the anchor job, i.e. are directly or * indirectly a dependency of the anchor job via paths that * are fully marked as mattering. */ if (j) l = j->subject_list; else l = m->transaction_anchor; LIST_FOREACH(subject, l, l) { /* This link does not matter */ if (!l->matters) continue; /* This unit has already been marked */ if (l->object->generation == generation) continue; l->object->matters_to_anchor = true; l->object->generation = generation; transaction_find_jobs_that_matter_to_anchor(m, l->object, generation); } } static void transaction_merge_and_delete_job(Manager *m, Job *j, Job *other, JobType t) { JobDependency *l, *last; assert(j); assert(other); assert(j->unit == other->unit); assert(!j->installed); /* Merges 'other' into 'j' and then deletes j. */ j->type = t; j->state = JOB_WAITING; j->override = j->override || other->override; j->matters_to_anchor = j->matters_to_anchor || other->matters_to_anchor; /* Patch us in as new owner of the JobDependency objects */ last = NULL; LIST_FOREACH(subject, l, other->subject_list) { assert(l->subject == other); l->subject = j; last = l; } /* Merge both lists */ if (last) { last->subject_next = j->subject_list; if (j->subject_list) j->subject_list->subject_prev = last; j->subject_list = other->subject_list; } /* Patch us in as new owner of the JobDependency objects */ last = NULL; LIST_FOREACH(object, l, other->object_list) { assert(l->object == other); l->object = j; last = l; } /* Merge both lists */ if (last) { last->object_next = j->object_list; if (j->object_list) j->object_list->object_prev = last; j->object_list = other->object_list; } /* Kill the other job */ other->subject_list = NULL; other->object_list = NULL; transaction_delete_job(m, other, true); } static bool job_is_conflicted_by(Job *j) { JobDependency *l; assert(j); /* Returns true if this job is pulled in by a least one * ConflictedBy dependency. */ LIST_FOREACH(object, l, j->object_list) if (l->conflicts) return true; return false; } static int delete_one_unmergeable_job(Manager *m, Job *j) { Job *k; assert(j); /* Tries to delete one item in the linked list * j->transaction_next->transaction_next->... that conflicts * whith another one, in an attempt to make an inconsistent * transaction work. */ /* We rely here on the fact that if a merged with b does not * merge with c, either a or b merge with c neither */ LIST_FOREACH(transaction, j, j) LIST_FOREACH(transaction, k, j->transaction_next) { Job *d; /* Is this one mergeable? Then skip it */ if (job_type_is_mergeable(j->type, k->type)) continue; /* Ok, we found two that conflict, let's see if we can * drop one of them */ if (!j->matters_to_anchor && !k->matters_to_anchor) { /* Both jobs don't matter, so let's * find the one that is smarter to * remove. Let's think positive and * rather remove stops then starts -- * except if something is being * stopped because it is conflicted by * another unit in which case we * rather remove the start. */ log_debug("Looking at job %s/%s conflicted_by=%s", j->unit->meta.id, job_type_to_string(j->type), yes_no(j->type == JOB_STOP && job_is_conflicted_by(j))); log_debug("Looking at job %s/%s conflicted_by=%s", k->unit->meta.id, job_type_to_string(k->type), yes_no(k->type == JOB_STOP && job_is_conflicted_by(k))); if (j->type == JOB_STOP) { if (job_is_conflicted_by(j)) d = k; else d = j; } else if (k->type == JOB_STOP) { if (job_is_conflicted_by(k)) d = j; else d = k; } else d = j; } else if (!j->matters_to_anchor) d = j; else if (!k->matters_to_anchor) d = k; else return -ENOEXEC; /* Ok, we can drop one, so let's do so. */ log_debug("Fixing conflicting jobs by deleting job %s/%s", d->unit->meta.id, job_type_to_string(d->type)); transaction_delete_job(m, d, true); return 0; } return -EINVAL; } static int transaction_merge_jobs(Manager *m, DBusError *e) { Job *j; Iterator i; int r; assert(m); /* First step, check whether any of the jobs for one specific * task conflict. If so, try to drop one of them. */ HASHMAP_FOREACH(j, m->transaction_jobs, i) { JobType t; Job *k; t = j->type; LIST_FOREACH(transaction, k, j->transaction_next) { if (job_type_merge(&t, k->type) >= 0) continue; /* OK, we could not merge all jobs for this * action. Let's see if we can get rid of one * of them */ if ((r = delete_one_unmergeable_job(m, j)) >= 0) /* Ok, we managed to drop one, now * let's ask our callers to call us * again after garbage collecting */ return -EAGAIN; /* We couldn't merge anything. Failure */ dbus_set_error(e, BUS_ERROR_TRANSACTION_JOBS_CONFLICTING, "Transaction contains conflicting jobs '%s' and '%s' for %s. Probably contradicting requirement dependencies configured.", job_type_to_string(t), job_type_to_string(k->type), k->unit->meta.id); return r; } } /* Second step, merge the jobs. */ HASHMAP_FOREACH(j, m->transaction_jobs, i) { JobType t = j->type; Job *k; /* Merge all transactions */ LIST_FOREACH(transaction, k, j->transaction_next) assert_se(job_type_merge(&t, k->type) == 0); /* If an active job is mergeable, merge it too */ if (j->unit->meta.job) job_type_merge(&t, j->unit->meta.job->type); /* Might fail. Which is OK */ while ((k = j->transaction_next)) { if (j->installed) { transaction_merge_and_delete_job(m, k, j, t); j = k; } else transaction_merge_and_delete_job(m, j, k, t); } assert(!j->transaction_next); assert(!j->transaction_prev); } return 0; } static void transaction_drop_redundant(Manager *m) { bool again; assert(m); /* Goes through the transaction and removes all jobs that are * a noop */ do { Job *j; Iterator i; again = false; HASHMAP_FOREACH(j, m->transaction_jobs, i) { bool changes_something = false; Job *k; LIST_FOREACH(transaction, k, j) { if (!job_is_anchor(k) && (j->installed || job_type_is_redundant(k->type, unit_active_state(k->unit)))) continue; changes_something = true; break; } if (changes_something) continue; /* log_debug("Found redundant job %s/%s, dropping.", j->unit->meta.id, job_type_to_string(j->type)); */ transaction_delete_job(m, j, false); again = true; break; } } while (again); } static bool unit_matters_to_anchor(Unit *u, Job *j) { assert(u); assert(!j->transaction_prev); /* Checks whether at least one of the jobs for this unit * matters to the anchor. */ LIST_FOREACH(transaction, j, j) if (j->matters_to_anchor) return true; return false; } static int transaction_verify_order_one(Manager *m, Job *j, Job *from, unsigned generation, DBusError *e) { Iterator i; Unit *u; int r; assert(m); assert(j); assert(!j->transaction_prev); /* Does a recursive sweep through the ordering graph, looking * for a cycle. If we find cycle we try to break it. */ /* Have we seen this before? */ if (j->generation == generation) { Job *k, *delete; /* If the marker is NULL we have been here already and * decided the job was loop-free from here. Hence * shortcut things and return right-away. */ if (!j->marker) return 0; /* So, the marker is not NULL and we already have been * here. We have a cycle. Let's try to break it. We go * backwards in our path and try to find a suitable * job to remove. We use the marker to find our way * back, since smart how we are we stored our way back * in there. */ log_warning("Found ordering cycle on %s/%s", j->unit->meta.id, job_type_to_string(j->type)); delete = NULL; for (k = from; k; k = ((k->generation == generation && k->marker != k) ? k->marker : NULL)) { log_info("Walked on cycle path to %s/%s", k->unit->meta.id, job_type_to_string(k->type)); if (!delete && !k->installed && !unit_matters_to_anchor(k->unit, k)) { /* Ok, we can drop this one, so let's * do so. */ delete = k; } /* Check if this in fact was the beginning of * the cycle */ if (k == j) break; } if (delete) { log_warning("Breaking ordering cycle by deleting job %s/%s", delete->unit->meta.id, job_type_to_string(delete->type)); transaction_delete_unit(m, delete->unit); return -EAGAIN; } log_error("Unable to break cycle"); dbus_set_error(e, BUS_ERROR_TRANSACTION_ORDER_IS_CYCLIC, "Transaction order is cyclic. See system logs for details."); return -ENOEXEC; } /* Make the marker point to where we come from, so that we can * find our way backwards if we want to break a cycle. We use * a special marker for the beginning: we point to * ourselves. */ j->marker = from ? from : j; j->generation = generation; /* We assume that the the dependencies are bidirectional, and * hence can ignore UNIT_AFTER */ SET_FOREACH(u, j->unit->meta.dependencies[UNIT_BEFORE], i) { Job *o; /* Is there a job for this unit? */ if (!(o = hashmap_get(m->transaction_jobs, u))) /* Ok, there is no job for this in the * transaction, but maybe there is already one * running? */ if (!(o = u->meta.job)) continue; if ((r = transaction_verify_order_one(m, o, j, generation, e)) < 0) return r; } /* Ok, let's backtrack, and remember that this entry is not on * our path anymore. */ j->marker = NULL; return 0; } static int transaction_verify_order(Manager *m, unsigned *generation, DBusError *e) { Job *j; int r; Iterator i; unsigned g; assert(m); assert(generation); /* Check if the ordering graph is cyclic. If it is, try to fix * that up by dropping one of the jobs. */ g = (*generation)++; HASHMAP_FOREACH(j, m->transaction_jobs, i) if ((r = transaction_verify_order_one(m, j, NULL, g, e)) < 0) return r; return 0; } static void transaction_collect_garbage(Manager *m) { bool again; assert(m); /* Drop jobs that are not required by any other job */ do { Iterator i; Job *j; again = false; HASHMAP_FOREACH(j, m->transaction_jobs, i) { if (j->object_list) { /* log_debug("Keeping job %s/%s because of %s/%s", */ /* j->unit->meta.id, job_type_to_string(j->type), */ /* j->object_list->subject ? j->object_list->subject->unit->meta.id : "root", */ /* j->object_list->subject ? job_type_to_string(j->object_list->subject->type) : "root"); */ continue; } /* log_debug("Garbage collecting job %s/%s", j->unit->meta.id, job_type_to_string(j->type)); */ transaction_delete_job(m, j, true); again = true; break; } } while (again); } static int transaction_is_destructive(Manager *m, DBusError *e) { Iterator i; Job *j; assert(m); /* Checks whether applying this transaction means that * existing jobs would be replaced */ HASHMAP_FOREACH(j, m->transaction_jobs, i) { /* Assume merged */ assert(!j->transaction_prev); assert(!j->transaction_next); if (j->unit->meta.job && j->unit->meta.job != j && !job_type_is_superset(j->type, j->unit->meta.job->type)) { dbus_set_error(e, BUS_ERROR_TRANSACTION_IS_DESTRUCTIVE, "Transaction is destructive."); return -EEXIST; } } return 0; } static void transaction_minimize_impact(Manager *m) { bool again; assert(m); /* Drops all unnecessary jobs that reverse already active jobs * or that stop a running service. */ do { Job *j; Iterator i; again = false; HASHMAP_FOREACH(j, m->transaction_jobs, i) { LIST_FOREACH(transaction, j, j) { bool stops_running_service, changes_existing_job; /* If it matters, we shouldn't drop it */ if (j->matters_to_anchor) continue; /* Would this stop a running service? * Would this change an existing job? * If so, let's drop this entry */ stops_running_service = j->type == JOB_STOP && UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(j->unit)); changes_existing_job = j->unit->meta.job && job_type_is_conflicting(j->type, j->unit->meta.job->type); if (!stops_running_service && !changes_existing_job) continue; if (stops_running_service) log_info("%s/%s would stop a running service.", j->unit->meta.id, job_type_to_string(j->type)); if (changes_existing_job) log_info("%s/%s would change existing job.", j->unit->meta.id, job_type_to_string(j->type)); /* Ok, let's get rid of this */ log_info("Deleting %s/%s to minimize impact.", j->unit->meta.id, job_type_to_string(j->type)); transaction_delete_job(m, j, true); again = true; break; } if (again) break; } } while (again); } static int transaction_apply(Manager *m) { Iterator i; Job *j; int r; /* Moves the transaction jobs to the set of active jobs */ HASHMAP_FOREACH(j, m->transaction_jobs, i) { /* Assume merged */ assert(!j->transaction_prev); assert(!j->transaction_next); if (j->installed) continue; if ((r = hashmap_put(m->jobs, UINT32_TO_PTR(j->id), j)) < 0) goto rollback; } while ((j = hashmap_steal_first(m->transaction_jobs))) { if (j->installed) { /* log_debug("Skipping already installed job %s/%s as %u", j->unit->meta.id, job_type_to_string(j->type), (unsigned) j->id); */ continue; } if (j->unit->meta.job) job_free(j->unit->meta.job); j->unit->meta.job = j; j->installed = true; m->n_installed_jobs ++; /* We're fully installed. Now let's free data we don't * need anymore. */ assert(!j->transaction_next); assert(!j->transaction_prev); job_add_to_run_queue(j); job_add_to_dbus_queue(j); job_start_timer(j); log_debug("Installed new job %s/%s as %u", j->unit->meta.id, job_type_to_string(j->type), (unsigned) j->id); } /* As last step, kill all remaining job dependencies. */ transaction_clean_dependencies(m); return 0; rollback: HASHMAP_FOREACH(j, m->transaction_jobs, i) { if (j->installed) continue; hashmap_remove(m->jobs, UINT32_TO_PTR(j->id)); } return r; } static int transaction_activate(Manager *m, JobMode mode, DBusError *e) { int r; unsigned generation = 1; assert(m); /* This applies the changes recorded in transaction_jobs to * the actual list of jobs, if possible. */ /* First step: figure out which jobs matter */ transaction_find_jobs_that_matter_to_anchor(m, NULL, generation++); /* Second step: Try not to stop any running services if * we don't have to. Don't try to reverse running * jobs if we don't have to. */ if (mode == JOB_FAIL) transaction_minimize_impact(m); /* Third step: Drop redundant jobs */ transaction_drop_redundant(m); for (;;) { /* Fourth step: Let's remove unneeded jobs that might * be lurking. */ transaction_collect_garbage(m); /* Fifth step: verify order makes sense and correct * cycles if necessary and possible */ if ((r = transaction_verify_order(m, &generation, e)) >= 0) break; if (r != -EAGAIN) { log_warning("Requested transaction contains an unfixable cyclic ordering dependency: %s", bus_error(e, r)); goto rollback; } /* Let's see if the resulting transaction ordering * graph is still cyclic... */ } for (;;) { /* Sixth step: let's drop unmergeable entries if * necessary and possible, merge entries we can * merge */ if ((r = transaction_merge_jobs(m, e)) >= 0) break; if (r != -EAGAIN) { log_warning("Requested transaction contains unmergable jobs: %s", bus_error(e, r)); goto rollback; } /* Seventh step: an entry got dropped, let's garbage * collect its dependencies. */ transaction_collect_garbage(m); /* Let's see if the resulting transaction still has * unmergeable entries ... */ } /* Eights step: Drop redundant jobs again, if the merging now allows us to drop more. */ transaction_drop_redundant(m); /* Ninth step: check whether we can actually apply this */ if (mode == JOB_FAIL) if ((r = transaction_is_destructive(m, e)) < 0) { log_notice("Requested transaction contradicts existing jobs: %s", bus_error(e, r)); goto rollback; } /* Tenth step: apply changes */ if ((r = transaction_apply(m)) < 0) { log_warning("Failed to apply transaction: %s", strerror(-r)); goto rollback; } assert(hashmap_isempty(m->transaction_jobs)); assert(!m->transaction_anchor); return 0; rollback: transaction_abort(m); return r; } static Job* transaction_add_one_job(Manager *m, JobType type, Unit *unit, bool override, bool *is_new) { Job *j, *f; assert(m); assert(unit); /* Looks for an axisting prospective job and returns that. If * it doesn't exist it is created and added to the prospective * jobs list. */ f = hashmap_get(m->transaction_jobs, unit); LIST_FOREACH(transaction, j, f) { assert(j->unit == unit); if (j->type == type) { if (is_new) *is_new = false; return j; } } if (unit->meta.job && unit->meta.job->type == type) j = unit->meta.job; else if (!(j = job_new(m, type, unit))) return NULL; j->generation = 0; j->marker = NULL; j->matters_to_anchor = false; j->override = override; LIST_PREPEND(Job, transaction, f, j); if (hashmap_replace(m->transaction_jobs, unit, f) < 0) { job_free(j); return NULL; } if (is_new) *is_new = true; /* log_debug("Added job %s/%s to transaction.", unit->meta.id, job_type_to_string(type)); */ return j; } void manager_transaction_unlink_job(Manager *m, Job *j, bool delete_dependencies) { assert(m); assert(j); if (j->transaction_prev) j->transaction_prev->transaction_next = j->transaction_next; else if (j->transaction_next) hashmap_replace(m->transaction_jobs, j->unit, j->transaction_next); else hashmap_remove_value(m->transaction_jobs, j->unit, j); if (j->transaction_next) j->transaction_next->transaction_prev = j->transaction_prev; j->transaction_prev = j->transaction_next = NULL; while (j->subject_list) job_dependency_free(j->subject_list); while (j->object_list) { Job *other = j->object_list->matters ? j->object_list->subject : NULL; job_dependency_free(j->object_list); if (other && delete_dependencies) { log_debug("Deleting job %s/%s as dependency of job %s/%s", other->unit->meta.id, job_type_to_string(other->type), j->unit->meta.id, job_type_to_string(j->type)); transaction_delete_job(m, other, delete_dependencies); } } } static int transaction_add_job_and_dependencies( Manager *m, JobType type, Unit *unit, Job *by, bool matters, bool override, bool conflicts, DBusError *e, Job **_ret) { Job *ret; Iterator i; Unit *dep; int r; bool is_new; assert(m); assert(type < _JOB_TYPE_MAX); assert(unit); if (unit->meta.load_state != UNIT_LOADED && unit->meta.load_state != UNIT_ERROR && unit->meta.load_state != UNIT_MASKED) { dbus_set_error(e, BUS_ERROR_LOAD_FAILED, "Unit %s is not loaded properly.", unit->meta.id); return -EINVAL; } if (type != JOB_STOP && unit->meta.load_state == UNIT_ERROR) { dbus_set_error(e, BUS_ERROR_LOAD_FAILED, "Unit %s failed to load: %s. " "See system logs and 'systemctl status' for details.", unit->meta.id, strerror(-unit->meta.load_error)); return -EINVAL; } if (type != JOB_STOP && unit->meta.load_state == UNIT_MASKED) { dbus_set_error(e, BUS_ERROR_MASKED, "Unit %s is masked.", unit->meta.id); return -EINVAL; } if (!unit_job_is_applicable(unit, type)) { dbus_set_error(e, BUS_ERROR_JOB_TYPE_NOT_APPLICABLE, "Job type %s is not applicable for unit %s.", job_type_to_string(type), unit->meta.id); return -EBADR; } /* First add the job. */ if (!(ret = transaction_add_one_job(m, type, unit, override, &is_new))) return -ENOMEM; /* Then, add a link to the job. */ if (!job_dependency_new(by, ret, matters, conflicts)) return -ENOMEM; if (is_new) { Set *following; /* If we are following some other unit, make sure we * add all dependencies of everybody following. */ if (unit_following_set(ret->unit, &following) > 0) { SET_FOREACH(dep, following, i) if ((r = transaction_add_job_and_dependencies(m, type, dep, ret, false, override, false, e, NULL)) < 0) { log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, bus_error(e, r)); if (e) dbus_error_free(e); } set_free(following); } /* Finally, recursively add in all dependencies. */ if (type == JOB_START || type == JOB_RELOAD_OR_START) { SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRES], i) if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, true, override, false, e, NULL)) < 0) { if (r != -EBADR) goto fail; if (e) dbus_error_free(e); } SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_BIND_TO], i) if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, true, override, false, e, NULL)) < 0) { if (r != -EBADR) goto fail; if (e) dbus_error_free(e); } SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRES_OVERRIDABLE], i) if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, !override, override, false, e, NULL)) < 0) { log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, bus_error(e, r)); if (e) dbus_error_free(e); } SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_WANTS], i) if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, false, false, false, e, NULL)) < 0) { log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, bus_error(e, r)); if (e) dbus_error_free(e); } SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUISITE], i) if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_ACTIVE, dep, ret, true, override, false, e, NULL)) < 0) { if (r != -EBADR) goto fail; if (e) dbus_error_free(e); } SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUISITE_OVERRIDABLE], i) if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_ACTIVE, dep, ret, !override, override, false, e, NULL)) < 0) { log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, bus_error(e, r)); if (e) dbus_error_free(e); } SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_CONFLICTS], i) if ((r = transaction_add_job_and_dependencies(m, JOB_STOP, dep, ret, true, override, true, e, NULL)) < 0) { if (r != -EBADR) goto fail; if (e) dbus_error_free(e); } SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_CONFLICTED_BY], i) if ((r = transaction_add_job_and_dependencies(m, JOB_STOP, dep, ret, false, override, false, e, NULL)) < 0) { log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, bus_error(e, r)); if (e) dbus_error_free(e); } } else if (type == JOB_STOP || type == JOB_RESTART || type == JOB_TRY_RESTART) { SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUIRED_BY], i) if ((r = transaction_add_job_and_dependencies(m, type, dep, ret, true, override, false, e, NULL)) < 0) { if (r != -EBADR) goto fail; if (e) dbus_error_free(e); } SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_BOUND_BY], i) if ((r = transaction_add_job_and_dependencies(m, type, dep, ret, true, override, false, e, NULL)) < 0) { if (r != -EBADR) goto fail; if (e) dbus_error_free(e); } } /* JOB_VERIFY_STARTED, JOB_RELOAD require no dependency handling */ } if (_ret) *_ret = ret; return 0; fail: return r; } static int transaction_add_isolate_jobs(Manager *m) { Iterator i; Unit *u; char *k; int r; assert(m); HASHMAP_FOREACH_KEY(u, k, m->units, i) { /* ignore aliases */ if (u->meta.id != k) continue; if (UNIT_VTABLE(u)->no_isolate) continue; /* No need to stop inactive jobs */ if (UNIT_IS_INACTIVE_OR_FAILED(unit_active_state(u)) && !u->meta.job) continue; /* Is there already something listed for this? */ if (hashmap_get(m->transaction_jobs, u)) continue; if ((r = transaction_add_job_and_dependencies(m, JOB_STOP, u, NULL, true, false, false, NULL, NULL)) < 0) log_warning("Cannot add isolate job for unit %s, ignoring: %s", u->meta.id, strerror(-r)); } return 0; } int manager_add_job(Manager *m, JobType type, Unit *unit, JobMode mode, bool override, DBusError *e, Job **_ret) { int r; Job *ret; assert(m); assert(type < _JOB_TYPE_MAX); assert(unit); assert(mode < _JOB_MODE_MAX); if (mode == JOB_ISOLATE && type != JOB_START) { dbus_set_error(e, BUS_ERROR_INVALID_JOB_MODE, "Isolate is only valid for start."); return -EINVAL; } if (mode == JOB_ISOLATE && !unit->meta.allow_isolate) { dbus_set_error(e, BUS_ERROR_NO_ISOLATION, "Operation refused, unit may not be isolated."); return -EPERM; } log_debug("Trying to enqueue job %s/%s/%s", unit->meta.id, job_type_to_string(type), job_mode_to_string(mode)); if ((r = transaction_add_job_and_dependencies(m, type, unit, NULL, true, override, false, e, &ret)) < 0) { transaction_abort(m); return r; } if (mode == JOB_ISOLATE) if ((r = transaction_add_isolate_jobs(m)) < 0) { transaction_abort(m); return r; } if ((r = transaction_activate(m, mode, e)) < 0) return r; log_debug("Enqueued job %s/%s as %u", unit->meta.id, job_type_to_string(type), (unsigned) ret->id); if (_ret) *_ret = ret; return 0; } int manager_add_job_by_name(Manager *m, JobType type, const char *name, JobMode mode, bool override, DBusError *e, Job **_ret) { Unit *unit; int r; assert(m); assert(type < _JOB_TYPE_MAX); assert(name); assert(mode < _JOB_MODE_MAX); if ((r = manager_load_unit(m, name, NULL, NULL, &unit)) < 0) return r; return manager_add_job(m, type, unit, mode, override, e, _ret); } Job *manager_get_job(Manager *m, uint32_t id) { assert(m); return hashmap_get(m->jobs, UINT32_TO_PTR(id)); } Unit *manager_get_unit(Manager *m, const char *name) { assert(m); assert(name); return hashmap_get(m->units, name); } unsigned manager_dispatch_load_queue(Manager *m) { Meta *meta; unsigned n = 0; assert(m); /* Make sure we are not run recursively */ if (m->dispatching_load_queue) return 0; m->dispatching_load_queue = true; /* Dispatches the load queue. Takes a unit from the queue and * tries to load its data until the queue is empty */ while ((meta = m->load_queue)) { assert(meta->in_load_queue); unit_load((Unit*) meta); n++; } m->dispatching_load_queue = false; return n; } int manager_load_unit_prepare(Manager *m, const char *name, const char *path, DBusError *e, Unit **_ret) { Unit *ret; int r; assert(m); assert(name || path); /* This will prepare the unit for loading, but not actually * load anything from disk. */ if (path && !is_path(path)) { dbus_set_error(e, BUS_ERROR_INVALID_PATH, "Path %s is not absolute.", path); return -EINVAL; } if (!name) name = file_name_from_path(path); if (!unit_name_is_valid(name, false)) { dbus_set_error(e, BUS_ERROR_INVALID_NAME, "Unit name %s is not valid.", name); return -EINVAL; } if ((ret = manager_get_unit(m, name))) { *_ret = ret; return 1; } if (!(ret = unit_new(m))) return -ENOMEM; if (path) if (!(ret->meta.fragment_path = strdup(path))) { unit_free(ret); return -ENOMEM; } if ((r = unit_add_name(ret, name)) < 0) { unit_free(ret); return r; } unit_add_to_load_queue(ret); unit_add_to_dbus_queue(ret); unit_add_to_gc_queue(ret); if (_ret) *_ret = ret; return 0; } int manager_load_unit(Manager *m, const char *name, const char *path, DBusError *e, Unit **_ret) { int r; assert(m); /* This will load the service information files, but not actually * start any services or anything. */ if ((r = manager_load_unit_prepare(m, name, path, e, _ret)) != 0) return r; manager_dispatch_load_queue(m); if (_ret) *_ret = unit_follow_merge(*_ret); return 0; } void manager_dump_jobs(Manager *s, FILE *f, const char *prefix) { Iterator i; Job *j; assert(s); assert(f); HASHMAP_FOREACH(j, s->jobs, i) job_dump(j, f, prefix); } void manager_dump_units(Manager *s, FILE *f, const char *prefix) { Iterator i; Unit *u; const char *t; assert(s); assert(f); HASHMAP_FOREACH_KEY(u, t, s->units, i) if (u->meta.id == t) unit_dump(u, f, prefix); } void manager_clear_jobs(Manager *m) { Job *j; assert(m); transaction_abort(m); while ((j = hashmap_first(m->jobs))) job_free(j); } unsigned manager_dispatch_run_queue(Manager *m) { Job *j; unsigned n = 0; if (m->dispatching_run_queue) return 0; m->dispatching_run_queue = true; while ((j = m->run_queue)) { assert(j->installed); assert(j->in_run_queue); job_run_and_invalidate(j); n++; } m->dispatching_run_queue = false; return n; } unsigned manager_dispatch_dbus_queue(Manager *m) { Job *j; Meta *meta; unsigned n = 0; assert(m); if (m->dispatching_dbus_queue) return 0; m->dispatching_dbus_queue = true; while ((meta = m->dbus_unit_queue)) { assert(meta->in_dbus_queue); bus_unit_send_change_signal((Unit*) meta); n++; } while ((j = m->dbus_job_queue)) { assert(j->in_dbus_queue); bus_job_send_change_signal(j); n++; } m->dispatching_dbus_queue = false; return n; } static int manager_process_notify_fd(Manager *m) { ssize_t n; assert(m); for (;;) { char buf[4096]; struct msghdr msghdr; struct iovec iovec; struct ucred *ucred; union { struct cmsghdr cmsghdr; uint8_t buf[CMSG_SPACE(sizeof(struct ucred))]; } control; Unit *u; char **tags; zero(iovec); iovec.iov_base = buf; iovec.iov_len = sizeof(buf)-1; zero(control); zero(msghdr); msghdr.msg_iov = &iovec; msghdr.msg_iovlen = 1; msghdr.msg_control = &control; msghdr.msg_controllen = sizeof(control); if ((n = recvmsg(m->notify_watch.fd, &msghdr, MSG_DONTWAIT)) <= 0) { if (n >= 0) return -EIO; if (errno == EAGAIN || errno == EINTR) break; return -errno; } if (msghdr.msg_controllen < CMSG_LEN(sizeof(struct ucred)) || control.cmsghdr.cmsg_level != SOL_SOCKET || control.cmsghdr.cmsg_type != SCM_CREDENTIALS || control.cmsghdr.cmsg_len != CMSG_LEN(sizeof(struct ucred))) { log_warning("Received notify message without credentials. Ignoring."); continue; } ucred = (struct ucred*) CMSG_DATA(&control.cmsghdr); if (!(u = hashmap_get(m->watch_pids, LONG_TO_PTR(ucred->pid)))) if (!(u = cgroup_unit_by_pid(m, ucred->pid))) { log_warning("Cannot find unit for notify message of PID %lu.", (unsigned long) ucred->pid); continue; } assert((size_t) n < sizeof(buf)); buf[n] = 0; if (!(tags = strv_split(buf, "\n\r"))) return -ENOMEM; log_debug("Got notification message for unit %s", u->meta.id); if (UNIT_VTABLE(u)->notify_message) UNIT_VTABLE(u)->notify_message(u, ucred->pid, tags); strv_free(tags); } return 0; } static int manager_dispatch_sigchld(Manager *m) { assert(m); for (;;) { siginfo_t si; Unit *u; int r; zero(si); /* First we call waitd() for a PID and do not reap the * zombie. That way we can still access /proc/$PID for * it while it is a zombie. */ if (waitid(P_ALL, 0, &si, WEXITED|WNOHANG|WNOWAIT) < 0) { if (errno == ECHILD) break; if (errno == EINTR) continue; return -errno; } if (si.si_pid <= 0) break; if (si.si_code == CLD_EXITED || si.si_code == CLD_KILLED || si.si_code == CLD_DUMPED) { char *name = NULL; get_process_name(si.si_pid, &name); log_debug("Got SIGCHLD for process %lu (%s)", (unsigned long) si.si_pid, strna(name)); free(name); } /* Let's flush any message the dying child might still * have queued for us. This ensures that the process * still exists in /proc so that we can figure out * which cgroup and hence unit it belongs to. */ if ((r = manager_process_notify_fd(m)) < 0) return r; /* And now figure out the unit this belongs to */ if (!(u = hashmap_get(m->watch_pids, LONG_TO_PTR(si.si_pid)))) u = cgroup_unit_by_pid(m, si.si_pid); /* And now, we actually reap the zombie. */ if (waitid(P_PID, si.si_pid, &si, WEXITED) < 0) { if (errno == EINTR) continue; return -errno; } if (si.si_code != CLD_EXITED && si.si_code != CLD_KILLED && si.si_code != CLD_DUMPED) continue; log_debug("Child %lu died (code=%s, status=%i/%s)", (long unsigned) si.si_pid, sigchld_code_to_string(si.si_code), si.si_status, strna(si.si_code == CLD_EXITED ? exit_status_to_string(si.si_status, EXIT_STATUS_FULL) : signal_to_string(si.si_status))); if (!u) continue; log_debug("Child %lu belongs to %s", (long unsigned) si.si_pid, u->meta.id); hashmap_remove(m->watch_pids, LONG_TO_PTR(si.si_pid)); UNIT_VTABLE(u)->sigchld_event(u, si.si_pid, si.si_code, si.si_status); } return 0; } static int manager_start_target(Manager *m, const char *name, JobMode mode) { int r; DBusError error; dbus_error_init(&error); log_info("Activating special unit %s", name); if ((r = manager_add_job_by_name(m, JOB_START, name, mode, true, &error, NULL)) < 0) log_error("Failed to enqueue %s job: %s", name, bus_error(&error, r)); dbus_error_free(&error); return r; } static int manager_process_signal_fd(Manager *m) { ssize_t n; struct signalfd_siginfo sfsi; bool sigchld = false; assert(m); for (;;) { if ((n = read(m->signal_watch.fd, &sfsi, sizeof(sfsi))) != sizeof(sfsi)) { if (n >= 0) return -EIO; if (errno == EINTR || errno == EAGAIN) break; return -errno; } log_debug("Received SIG%s", strna(signal_to_string(sfsi.ssi_signo))); switch (sfsi.ssi_signo) { case SIGCHLD: sigchld = true; break; case SIGTERM: if (m->running_as == MANAGER_SYSTEM) { /* This is for compatibility with the * original sysvinit */ m->exit_code = MANAGER_REEXECUTE; break; } /* Fall through */ case SIGINT: if (m->running_as == MANAGER_SYSTEM) { manager_start_target(m, SPECIAL_CTRL_ALT_DEL_TARGET, JOB_REPLACE); break; } /* Run the exit target if there is one, if not, just exit. */ if (manager_start_target(m, SPECIAL_EXIT_TARGET, JOB_REPLACE) < 0) { m->exit_code = MANAGER_EXIT; return 0; } break; case SIGWINCH: if (m->running_as == MANAGER_SYSTEM) manager_start_target(m, SPECIAL_KBREQUEST_TARGET, JOB_REPLACE); /* This is a nop on non-init */ break; case SIGPWR: if (m->running_as == MANAGER_SYSTEM) manager_start_target(m, SPECIAL_SIGPWR_TARGET, JOB_REPLACE); /* This is a nop on non-init */ break; case SIGUSR1: { Unit *u; u = manager_get_unit(m, SPECIAL_DBUS_SERVICE); if (!u || UNIT_IS_ACTIVE_OR_RELOADING(unit_active_state(u))) { log_info("Trying to reconnect to bus..."); bus_init(m); } if (!u || !UNIT_IS_ACTIVE_OR_ACTIVATING(unit_active_state(u))) { log_info("Loading D-Bus service..."); manager_start_target(m, SPECIAL_DBUS_SERVICE, JOB_REPLACE); } break; } case SIGUSR2: { FILE *f; char *dump = NULL; size_t size; if (!(f = open_memstream(&dump, &size))) { log_warning("Failed to allocate memory stream."); break; } manager_dump_units(m, f, "\t"); manager_dump_jobs(m, f, "\t"); if (ferror(f)) { fclose(f); free(dump); log_warning("Failed to write status stream"); break; } fclose(f); log_dump(LOG_INFO, dump); free(dump); break; } case SIGHUP: m->exit_code = MANAGER_RELOAD; break; default: { /* Starting SIGRTMIN+0 */ static const char * const target_table[] = { [0] = SPECIAL_DEFAULT_TARGET, [1] = SPECIAL_RESCUE_TARGET, [2] = SPECIAL_EMERGENCY_TARGET, [3] = SPECIAL_HALT_TARGET, [4] = SPECIAL_POWEROFF_TARGET, [5] = SPECIAL_REBOOT_TARGET, [6] = SPECIAL_KEXEC_TARGET }; /* Starting SIGRTMIN+13, so that target halt and system halt are 10 apart */ static const ManagerExitCode code_table[] = { [0] = MANAGER_HALT, [1] = MANAGER_POWEROFF, [2] = MANAGER_REBOOT, [3] = MANAGER_KEXEC }; if ((int) sfsi.ssi_signo >= SIGRTMIN+0 && (int) sfsi.ssi_signo < SIGRTMIN+(int) ELEMENTSOF(target_table)) { manager_start_target(m, target_table[sfsi.ssi_signo - SIGRTMIN], (sfsi.ssi_signo == 1 || sfsi.ssi_signo == 2) ? JOB_ISOLATE : JOB_REPLACE); break; } if ((int) sfsi.ssi_signo >= SIGRTMIN+13 && (int) sfsi.ssi_signo < SIGRTMIN+13+(int) ELEMENTSOF(code_table)) { m->exit_code = code_table[sfsi.ssi_signo - SIGRTMIN - 13]; break; } log_warning("Got unhandled signal <%s>.", strna(signal_to_string(sfsi.ssi_signo))); } } } if (sigchld) return manager_dispatch_sigchld(m); return 0; } static int process_event(Manager *m, struct epoll_event *ev) { int r; Watch *w; assert(m); assert(ev); assert(w = ev->data.ptr); if (w->type == WATCH_INVALID) return 0; switch (w->type) { case WATCH_SIGNAL: /* An incoming signal? */ if (ev->events != EPOLLIN) return -EINVAL; if ((r = manager_process_signal_fd(m)) < 0) return r; break; case WATCH_NOTIFY: /* An incoming daemon notification event? */ if (ev->events != EPOLLIN) return -EINVAL; if ((r = manager_process_notify_fd(m)) < 0) return r; break; case WATCH_FD: /* Some fd event, to be dispatched to the units */ UNIT_VTABLE(w->data.unit)->fd_event(w->data.unit, w->fd, ev->events, w); break; case WATCH_UNIT_TIMER: case WATCH_JOB_TIMER: { uint64_t v; ssize_t k; /* Some timer event, to be dispatched to the units */ if ((k = read(w->fd, &v, sizeof(v))) != sizeof(v)) { if (k < 0 && (errno == EINTR || errno == EAGAIN)) break; return k < 0 ? -errno : -EIO; } if (w->type == WATCH_UNIT_TIMER) UNIT_VTABLE(w->data.unit)->timer_event(w->data.unit, v, w); else job_timer_event(w->data.job, v, w); break; } case WATCH_MOUNT: /* Some mount table change, intended for the mount subsystem */ mount_fd_event(m, ev->events); break; case WATCH_SWAP: /* Some swap table change, intended for the swap subsystem */ swap_fd_event(m, ev->events); break; case WATCH_UDEV: /* Some notification from udev, intended for the device subsystem */ device_fd_event(m, ev->events); break; case WATCH_DBUS_WATCH: bus_watch_event(m, w, ev->events); break; case WATCH_DBUS_TIMEOUT: bus_timeout_event(m, w, ev->events); break; default: log_error("event type=%i", w->type); assert_not_reached("Unknown epoll event type."); } return 0; } int manager_loop(Manager *m) { int r; RATELIMIT_DEFINE(rl, 1*USEC_PER_SEC, 1000); assert(m); m->exit_code = MANAGER_RUNNING; /* Release the path cache */ set_free_free(m->unit_path_cache); m->unit_path_cache = NULL; manager_check_finished(m); /* There might still be some zombies hanging around from * before we were exec()'ed. Leat's reap them */ if ((r = manager_dispatch_sigchld(m)) < 0) return r; while (m->exit_code == MANAGER_RUNNING) { struct epoll_event event; int n; if (!ratelimit_test(&rl)) { /* Yay, something is going seriously wrong, pause a little */ log_warning("Looping too fast. Throttling execution a little."); sleep(1); } if (manager_dispatch_load_queue(m) > 0) continue; if (manager_dispatch_run_queue(m) > 0) continue; if (bus_dispatch(m) > 0) continue; if (manager_dispatch_cleanup_queue(m) > 0) continue; if (manager_dispatch_gc_queue(m) > 0) continue; if (manager_dispatch_dbus_queue(m) > 0) continue; if (swap_dispatch_reload(m) > 0) continue; if ((n = epoll_wait(m->epoll_fd, &event, 1, -1)) < 0) { if (errno == EINTR) continue; return -errno; } assert(n == 1); if ((r = process_event(m, &event)) < 0) return r; } return m->exit_code; } int manager_get_unit_from_dbus_path(Manager *m, const char *s, Unit **_u) { char *n; Unit *u; assert(m); assert(s); assert(_u); if (!startswith(s, "/org/freedesktop/systemd1/unit/")) return -EINVAL; if (!(n = bus_path_unescape(s+31))) return -ENOMEM; u = manager_get_unit(m, n); free(n); if (!u) return -ENOENT; *_u = u; return 0; } int manager_get_job_from_dbus_path(Manager *m, const char *s, Job **_j) { Job *j; unsigned id; int r; assert(m); assert(s); assert(_j); if (!startswith(s, "/org/freedesktop/systemd1/job/")) return -EINVAL; if ((r = safe_atou(s + 30, &id)) < 0) return r; if (!(j = manager_get_job(m, id))) return -ENOENT; *_j = j; return 0; } void manager_send_unit_audit(Manager *m, Unit *u, int type, bool success) { #ifdef HAVE_AUDIT char *p; if (m->audit_fd < 0) return; /* Don't generate audit events if the service was already * started and we're just deserializing */ if (m->n_deserializing > 0) return; if (!(p = unit_name_to_prefix_and_instance(u->meta.id))) { log_error("Failed to allocate unit name for audit message: %s", strerror(ENOMEM)); return; } if (audit_log_user_comm_message(m->audit_fd, type, "", p, NULL, NULL, NULL, success) < 0) log_error("Failed to send audit message: %m"); free(p); #endif } void manager_send_unit_plymouth(Manager *m, Unit *u) { int fd = -1; union sockaddr_union sa; int n = 0; char *message = NULL; ssize_t r; /* Don't generate plymouth events if the service was already * started and we're just deserializing */ if (m->n_deserializing > 0) return; if (m->running_as != MANAGER_SYSTEM) return; if (u->meta.type != UNIT_SERVICE && u->meta.type != UNIT_MOUNT && u->meta.type != UNIT_SWAP) return; /* We set SOCK_NONBLOCK here so that we rather drop the * message then wait for plymouth */ if ((fd = socket(AF_UNIX, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0)) < 0) { log_error("socket() failed: %m"); return; } zero(sa); sa.sa.sa_family = AF_UNIX; strncpy(sa.un.sun_path+1, "/ply-boot-protocol", sizeof(sa.un.sun_path)-1); if (connect(fd, &sa.sa, sizeof(sa.un)) < 0) { if (errno != EPIPE && errno != EAGAIN && errno != ENOENT && errno != ECONNREFUSED && errno != ECONNRESET && errno != ECONNABORTED) log_error("connect() failed: %m"); goto finish; } if (asprintf(&message, "U\002%c%s%n", (int) (strlen(u->meta.id) + 1), u->meta.id, &n) < 0) { log_error("Out of memory"); goto finish; } errno = 0; if ((r = write(fd, message, n + 1)) != n + 1) { if (errno != EPIPE && errno != EAGAIN && errno != ENOENT && errno != ECONNREFUSED && errno != ECONNRESET && errno != ECONNABORTED) log_error("Failed to write Plymouth message: %m"); goto finish; } finish: if (fd >= 0) close_nointr_nofail(fd); free(message); } void manager_dispatch_bus_name_owner_changed( Manager *m, const char *name, const char* old_owner, const char *new_owner) { Unit *u; assert(m); assert(name); if (!(u = hashmap_get(m->watch_bus, name))) return; UNIT_VTABLE(u)->bus_name_owner_change(u, name, old_owner, new_owner); } void manager_dispatch_bus_query_pid_done( Manager *m, const char *name, pid_t pid) { Unit *u; assert(m); assert(name); assert(pid >= 1); if (!(u = hashmap_get(m->watch_bus, name))) return; UNIT_VTABLE(u)->bus_query_pid_done(u, name, pid); } int manager_open_serialization(Manager *m, FILE **_f) { char *path; mode_t saved_umask; int fd; FILE *f; assert(_f); if (m->running_as == MANAGER_SYSTEM) { mkdir_p("/dev/.systemd", 0755); if (asprintf(&path, "/dev/.systemd/dump-%lu-XXXXXX", (unsigned long) getpid()) < 0) return -ENOMEM; } else { if (asprintf(&path, "/tmp/systemd-dump-%lu-XXXXXX", (unsigned long) getpid()) < 0) return -ENOMEM; } saved_umask = umask(0077); fd = mkostemp(path, O_RDWR|O_CLOEXEC); umask(saved_umask); if (fd < 0) { free(path); return -errno; } unlink(path); log_debug("Serializing state to %s", path); free(path); if (!(f = fdopen(fd, "w+")) < 0) return -errno; *_f = f; return 0; } int manager_serialize(Manager *m, FILE *f, FDSet *fds) { Iterator i; Unit *u; const char *t; int r; assert(m); assert(f); assert(fds); dual_timestamp_serialize(f, "initrd-timestamp", &m->initrd_timestamp); dual_timestamp_serialize(f, "startup-timestamp", &m->startup_timestamp); dual_timestamp_serialize(f, "finish-timestamp", &m->finish_timestamp); fputc('\n', f); HASHMAP_FOREACH_KEY(u, t, m->units, i) { if (u->meta.id != t) continue; if (!unit_can_serialize(u)) continue; /* Start marker */ fputs(u->meta.id, f); fputc('\n', f); if ((r = unit_serialize(u, f, fds)) < 0) return r; } if (ferror(f)) return -EIO; return 0; } int manager_deserialize(Manager *m, FILE *f, FDSet *fds) { int r = 0; assert(m); assert(f); log_debug("Deserializing state..."); m->n_deserializing ++; for (;;) { char line[1024], *l; if (!fgets(line, sizeof(line), f)) { if (feof(f)) r = 0; else r = -errno; goto finish; } char_array_0(line); l = strstrip(line); if (l[0] == 0) break; if (startswith(l, "initrd-timestamp=")) dual_timestamp_deserialize(l+17, &m->initrd_timestamp); else if (startswith(l, "startup-timestamp=")) dual_timestamp_deserialize(l+18, &m->startup_timestamp); else if (startswith(l, "finish-timestamp=")) dual_timestamp_deserialize(l+17, &m->finish_timestamp); else log_debug("Unknown serialization item '%s'", l); } for (;;) { Unit *u; char name[UNIT_NAME_MAX+2]; /* Start marker */ if (!fgets(name, sizeof(name), f)) { if (feof(f)) r = 0; else r = -errno; goto finish; } char_array_0(name); if ((r = manager_load_unit(m, strstrip(name), NULL, NULL, &u)) < 0) goto finish; if ((r = unit_deserialize(u, f, fds)) < 0) goto finish; } finish: if (ferror(f)) { r = -EIO; goto finish; } assert(m->n_deserializing > 0); m->n_deserializing --; return r; } int manager_reload(Manager *m) { int r, q; FILE *f; FDSet *fds; assert(m); if ((r = manager_open_serialization(m, &f)) < 0) return r; if (!(fds = fdset_new())) { r = -ENOMEM; goto finish; } if ((r = manager_serialize(m, f, fds)) < 0) goto finish; if (fseeko(f, 0, SEEK_SET) < 0) { r = -errno; goto finish; } /* From here on there is no way back. */ manager_clear_jobs_and_units(m); manager_undo_generators(m); /* Find new unit paths */ lookup_paths_free(&m->lookup_paths); if ((q = lookup_paths_init(&m->lookup_paths, m->running_as)) < 0) r = q; manager_run_generators(m); manager_build_unit_path_cache(m); m->n_deserializing ++; /* First, enumerate what we can from all config files */ if ((q = manager_enumerate(m)) < 0) r = q; /* Second, deserialize our stored data */ if ((q = manager_deserialize(m, f, fds)) < 0) r = q; fclose(f); f = NULL; /* Third, fire things up! */ if ((q = manager_coldplug(m)) < 0) r = q; assert(m->n_deserializing > 0); m->n_deserializing ++; finish: if (f) fclose(f); if (fds) fdset_free(fds); return r; } bool manager_is_booting_or_shutting_down(Manager *m) { Unit *u; assert(m); /* Is the initial job still around? */ if (manager_get_job(m, 1)) return true; /* Is there a job for the shutdown target? */ if (((u = manager_get_unit(m, SPECIAL_SHUTDOWN_TARGET)))) return !!u->meta.job; return false; } void manager_reset_failed(Manager *m) { Unit *u; Iterator i; assert(m); HASHMAP_FOREACH(u, m->units, i) unit_reset_failed(u); } int manager_set_console(Manager *m, const char *console) { char *c; assert(m); if (!(c = strdup(console))) return -ENOMEM; free(m->console); m->console = c; log_debug("Using kernel console %s", c); return 0; } bool manager_unit_pending_inactive(Manager *m, const char *name) { Unit *u; assert(m); assert(name); /* Returns true if the unit is inactive or going down */ if (!(u = manager_get_unit(m, name))) return true; return unit_pending_inactive(u); } void manager_check_finished(Manager *m) { char userspace[FORMAT_TIMESPAN_MAX], initrd[FORMAT_TIMESPAN_MAX], kernel[FORMAT_TIMESPAN_MAX], sum[FORMAT_TIMESPAN_MAX]; assert(m); if (dual_timestamp_is_set(&m->finish_timestamp)) return; if (hashmap_size(m->jobs) > 0) return; dual_timestamp_get(&m->finish_timestamp); if (m->running_as == MANAGER_SYSTEM) { if (dual_timestamp_is_set(&m->initrd_timestamp)) { log_info("Startup finished in %s (kernel) + %s (initrd) + %s (userspace) = %s.", format_timespan(kernel, sizeof(kernel), m->initrd_timestamp.monotonic), format_timespan(initrd, sizeof(initrd), m->startup_timestamp.monotonic - m->initrd_timestamp.monotonic), format_timespan(userspace, sizeof(userspace), m->finish_timestamp.monotonic - m->startup_timestamp.monotonic), format_timespan(sum, sizeof(sum), m->finish_timestamp.monotonic)); } else log_info("Startup finished in %s (kernel) + %s (userspace) = %s.", format_timespan(kernel, sizeof(kernel), m->startup_timestamp.monotonic), format_timespan(userspace, sizeof(userspace), m->finish_timestamp.monotonic - m->startup_timestamp.monotonic), format_timespan(sum, sizeof(sum), m->finish_timestamp.monotonic)); } else log_debug("Startup finished in %s.", format_timespan(userspace, sizeof(userspace), m->finish_timestamp.monotonic - m->startup_timestamp.monotonic)); } void manager_run_generators(Manager *m) { DIR *d = NULL; struct dirent *de; Hashmap *pids = NULL; const char *generator_path; assert(m); generator_path = m->running_as == MANAGER_SYSTEM ? SYSTEM_GENERATOR_PATH : SESSION_GENERATOR_PATH; if (!(d = opendir(generator_path))) { if (errno == ENOENT) return; log_error("Failed to enumerate generator directory: %m"); return; } if (!m->generator_unit_path) { char *p; char system_path[] = "/dev/.systemd/generator-XXXXXX", session_path[] = "/tmp/systemd-generator-XXXXXX"; if (!(p = mkdtemp(m->running_as == MANAGER_SYSTEM ? system_path : session_path))) { log_error("Failed to generate generator directory: %m"); goto finish; } if (!(m->generator_unit_path = strdup(p))) { log_error("Failed to allocate generator unit path."); goto finish; } } if (!(pids = hashmap_new(trivial_hash_func, trivial_compare_func))) { log_error("Failed to allocate set."); goto finish; } while ((de = readdir(d))) { char *path; pid_t pid; int k; if (ignore_file(de->d_name)) continue; if (de->d_type != DT_REG && de->d_type != DT_LNK && de->d_type != DT_UNKNOWN) continue; if (asprintf(&path, "%s/%s", generator_path, de->d_name) < 0) { log_error("Out of memory"); continue; } if ((pid = fork()) < 0) { log_error("Failed to fork: %m"); free(path); continue; } if (pid == 0) { const char *arguments[5]; /* Child */ arguments[0] = path; arguments[1] = m->generator_unit_path; arguments[2] = NULL; execv(path, (char **) arguments); log_error("Failed to execute %s: %m", path); _exit(EXIT_FAILURE); } log_debug("Spawned generator %s as %lu", path, (unsigned long) pid); if ((k = hashmap_put(pids, UINT_TO_PTR(pid), path)) < 0) { log_error("Failed to add PID to set: %s", strerror(-k)); free(path); } } while (!hashmap_isempty(pids)) { siginfo_t si; char *path; zero(si); if (waitid(P_ALL, 0, &si, WEXITED) < 0) { if (errno == EINTR) continue; log_error("waitid() failed: %m"); goto finish; } if ((path = hashmap_remove(pids, UINT_TO_PTR(si.si_pid)))) { if (!is_clean_exit(si.si_code, si.si_status)) { if (si.si_code == CLD_EXITED) log_error("%s exited with exit status %i.", path, si.si_status); else log_error("%s terminated by signal %s.", path, signal_to_string(si.si_status)); } else log_debug("Generator %s exited successfully.", path); free(path); } } if (rmdir(m->generator_unit_path) >= 0) { /* Uh? we were able to remove this dir? I guess that * means the directory was empty, hence let's shortcut * this */ free(m->generator_unit_path); m->generator_unit_path = NULL; goto finish; } if (!strv_find(m->lookup_paths.unit_path, m->generator_unit_path)) { char **l; if (!(l = strv_append(m->lookup_paths.unit_path, m->generator_unit_path))) { log_error("Failed to add generator directory to unit search path: %m"); goto finish; } strv_free(m->lookup_paths.unit_path); m->lookup_paths.unit_path = l; log_debug("Added generator unit path %s to search path.", m->generator_unit_path); } finish: if (d) closedir(d); if (pids) hashmap_free_free(pids); } void manager_undo_generators(Manager *m) { assert(m); if (!m->generator_unit_path) return; strv_remove(m->lookup_paths.unit_path, m->generator_unit_path); rm_rf(m->generator_unit_path, false, true); free(m->generator_unit_path); m->generator_unit_path = NULL; } static const char* const manager_running_as_table[_MANAGER_RUNNING_AS_MAX] = { [MANAGER_SYSTEM] = "system", [MANAGER_SESSION] = "session" }; DEFINE_STRING_TABLE_LOOKUP(manager_running_as, ManagerRunningAs);