diff options
Diffstat (limited to 'src/manager.c')
| -rw-r--r-- | src/manager.c | 2291 |
1 files changed, 2291 insertions, 0 deletions
diff --git a/src/manager.c b/src/manager.c new file mode 100644 index 0000000000..688d9fa65b --- /dev/null +++ b/src/manager.c @@ -0,0 +1,2291 @@ +/*-*- Mode: C; c-basic-offset: 8 -*-*/ + +/*** + 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 <http://www.gnu.org/licenses/>. +***/ + +#include <assert.h> +#include <errno.h> +#include <string.h> +#include <sys/epoll.h> +#include <signal.h> +#include <sys/signalfd.h> +#include <sys/wait.h> +#include <unistd.h> +#include <utmpx.h> +#include <sys/poll.h> +#include <sys/reboot.h> +#include <sys/ioctl.h> +#include <linux/kd.h> +#include <libcgroup.h> +#include <termios.h> +#include <fcntl.h> +#include <sys/types.h> +#include <sys/stat.h> + +#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 "utmp-wtmp.h" +#include "unit-name.h" +#include "dbus-unit.h" +#include "dbus-job.h" +#include "missing.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) + +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); + assert_se(sigaddset(&mask, SIGCHLD) == 0); + assert_se(sigaddset(&mask, SIGTERM) == 0); + assert_se(sigaddset(&mask, SIGHUP) == 0); + assert_se(sigaddset(&mask, SIGUSR1) == 0); + assert_se(sigaddset(&mask, SIGUSR2) == 0); + assert_se(sigaddset(&mask, SIGINT) == 0); /* Kernel sends us this on control-alt-del */ + assert_se(sigaddset(&mask, SIGWINCH) == 0); /* Kernel sends us this on kbrequest (alt-arrowup) */ + assert_se(sigaddset(&mask, SIGPWR) == 0); /* Some kernel drivers and upsd send us this on power failure */ + 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_INIT) + return enable_special_signals(m); + + return 0; +} + +static char** session_dirs(void) { + const char *home, *e; + char *config_home = NULL, *data_home = NULL; + char **config_dirs = NULL, **data_dirs = NULL; + char **r = NULL, **t; + + /* Implement the mechanisms defined in + * + * http://standards.freedesktop.org/basedir-spec/basedir-spec-0.6.html + * + * We look in both the config and the data dirs because we + * want to encourage that distributors ship their unit files + * as data, and allow overriding as configuration. + */ + + home = getenv("HOME"); + + if ((e = getenv("XDG_CONFIG_HOME"))) { + if (asprintf(&config_home, "%s/systemd/session", e) < 0) + goto fail; + + } else if (home) { + if (asprintf(&config_home, "%s/.config/systemd/session", home) < 0) + goto fail; + } + + if ((e = getenv("XDG_CONFIG_DIRS"))) + if (!(config_dirs = strv_split(e, ":"))) + goto fail; + + /* We don't treat /etc/xdg/systemd here as the spec + * suggests because we assume that that is a link to + * /etc/systemd/ anyway. */ + + if ((e = getenv("XDG_DATA_HOME"))) { + if (asprintf(&data_home, "%s/systemd/session", e) < 0) + goto fail; + + } else if (home) { + if (asprintf(&data_home, "%s/.local/share/systemd/session", home) < 0) + goto fail; + } + + if ((e = getenv("XDG_DATA_DIRS"))) + data_dirs = strv_split(e, ":"); + else + data_dirs = strv_new("/usr/local/share", "/usr/share", NULL); + + if (!data_dirs) + goto fail; + + /* Now merge everything we found. */ + if (config_home) { + if (!(t = strv_append(r, config_home))) + goto fail; + strv_free(r); + r = t; + } + + if (!(t = strv_merge_concat(r, config_dirs, "/systemd/session"))) + goto finish; + strv_free(r); + r = t; + + if (!(t = strv_append(r, SESSION_CONFIG_UNIT_PATH))) + goto fail; + strv_free(r); + r = t; + + if (data_home) { + if (!(t = strv_append(r, data_home))) + goto fail; + strv_free(r); + r = t; + } + + if (!(t = strv_merge_concat(r, data_dirs, "/systemd/session"))) + goto fail; + strv_free(r); + r = t; + + if (!(t = strv_append(r, SESSION_DATA_UNIT_PATH))) + goto fail; + strv_free(r); + r = t; + + if (!strv_path_make_absolute_cwd(r)) + goto fail; + +finish: + free(config_home); + strv_free(config_dirs); + free(data_home); + strv_free(data_dirs); + + return r; + +fail: + strv_free(r); + r = NULL; + goto finish; +} + +static int manager_find_paths(Manager *m) { + const char *e; + char *t; + + assert(m); + + /* First priority is whatever has been passed to us via env + * vars */ + if ((e = getenv("SYSTEMD_UNIT_PATH"))) + if (!(m->unit_path = split_path_and_make_absolute(e))) + return -ENOMEM; + + if (strv_isempty(m->unit_path)) { + + /* Nothing is set, so let's figure something out. */ + strv_free(m->unit_path); + + if (m->running_as == MANAGER_SESSION) { + if (!(m->unit_path = session_dirs())) + return -ENOMEM; + } else + if (!(m->unit_path = strv_new( + SYSTEM_CONFIG_UNIT_PATH, /* /etc/systemd/system/ */ + SYSTEM_DATA_UNIT_PATH, /* /lib/systemd/system/ */ + NULL))) + return -ENOMEM; + } + + if (m->running_as == MANAGER_INIT) { + /* /etc/init.d/ compatibility does not matter to users */ + + if ((e = getenv("SYSTEMD_SYSVINIT_PATH"))) + if (!(m->sysvinit_path = split_path_and_make_absolute(e))) + return -ENOMEM; + + if (strv_isempty(m->sysvinit_path)) { + strv_free(m->sysvinit_path); + + if (!(m->sysvinit_path = strv_new( + SYSTEM_SYSVINIT_PATH, /* /etc/init.d/ */ + NULL))) + return -ENOMEM; + } + + if ((e = getenv("SYSTEMD_SYSVRCND_PATH"))) + if (!(m->sysvrcnd_path = split_path_and_make_absolute(e))) + return -ENOMEM; + + if (strv_isempty(m->sysvrcnd_path)) { + strv_free(m->sysvrcnd_path); + + if (!(m->sysvrcnd_path = strv_new( + SYSTEM_SYSVRCND_PATH, /* /etc/rcN.d/ */ + NULL))) + return -ENOMEM; + } + } + + strv_uniq(m->unit_path); + strv_uniq(m->sysvinit_path); + strv_uniq(m->sysvrcnd_path); + + assert(!strv_isempty(m->unit_path)); + if (!(t = strv_join(m->unit_path, "\n\t"))) + return -ENOMEM; + log_debug("Looking for unit files in:\n\t%s", t); + free(t); + + if (!strv_isempty(m->sysvinit_path)) { + + if (!(t = strv_join(m->sysvinit_path, "\n\t"))) + return -ENOMEM; + + log_debug("Looking for SysV init scripts in:\n\t%s", t); + free(t); + } else + log_debug("Ignoring SysV init scripts."); + + if (!strv_isempty(m->sysvrcnd_path)) { + + if (!(t = strv_join(m->sysvrcnd_path, "\n\t"))) + return -ENOMEM; + + log_debug("Looking for SysV rcN.d links in:\n\t%s", t); + free(t); + } else + log_debug("Ignoring SysV rcN.d links."); + + return 0; +} + +int manager_new(ManagerRunningAs running_as, bool confirm_spawn, 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; + + m->boot_timestamp = now(CLOCK_REALTIME); + + m->running_as = running_as; + m->confirm_spawn = confirm_spawn; + m->name_data_slot = -1; + m->exit_code = _MANAGER_EXIT_CODE_INVALID; + + m->signal_watch.fd = m->mount_watch.fd = m->udev_watch.fd = m->epoll_fd = m->dev_autofs_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 = manager_find_paths(m)) < 0) + goto fail; + + if ((r = manager_setup_signals(m)) < 0) + goto fail; + + if ((r = manager_setup_cgroup(m)) < 0) + goto fail; + + /* Try to connect to the busses, if possible. */ + if ((r = bus_init_system(m)) < 0 || + (r = bus_init_api(m)) < 0) + goto fail; + + *_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); +} + +void manager_free(Manager *m) { + UnitType c; + + assert(m); + + manager_dispatch_cleanup_queue(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); + + bus_done_api(m); + bus_done_system(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); + + strv_free(m->unit_path); + strv_free(m->sysvinit_path); + strv_free(m->sysvrcnd_path); + strv_free(m->environment); + + free(m->cgroup_controller); + free(m->cgroup_hierarchy); + + hashmap_free(m->cgroup_bondings); + + 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 (UNIT_VTABLE(u)->coldplug) + if ((q = UNIT_VTABLE(u)->coldplug(u)) < 0) + r = q; + } + + return r; +} + +int manager_startup(Manager *m, FILE *serialization, FDSet *fds) { + int r, q; + + assert(m); + + /* 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; + + /* Now that the initial devices are available, let's see if we + * can write the utmp file */ + manager_write_utmp_reboot(m); + + 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 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) + 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("Trying to fix job merging 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) { + 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 ((r = 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 */ + 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) && + 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) { + 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. */ + + /* Did we find a cycle? */ + if (j->marker && j->generation == generation) { + Job *k; + + /* So, 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_debug("Found ordering cycle on %s/%s", j->unit->meta.id, job_type_to_string(j->type)); + + for (k = from; k; k = (k->generation == generation ? k->marker : NULL)) { + + log_debug("Walked on cycle path to %s/%s", k->unit->meta.id, job_type_to_string(k->type)); + + if (!k->installed && + !unit_matters_to_anchor(k->unit, k)) { + /* Ok, we can drop this one, so let's + * do so. */ + log_debug("Breaking order cycle by deleting job %s/%s", k->unit->meta.id, job_type_to_string(k->type)); + transaction_delete_unit(m, k->unit); + return -EAGAIN; + } + + /* Check if this in fact was the beginning of + * the cycle */ + if (k == j) + break; + } + + log_debug("Unable to break cycle"); + + 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 */ + j->marker = from; + 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)) < 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) { + Job *j; + int r; + Iterator i; + + 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. */ + + HASHMAP_FOREACH(j, m->transaction_jobs, i) + if ((r = transaction_verify_order_one(m, j, NULL, (*generation)++)) < 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) + 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) { + 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)) + 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->state); + + if (!stops_running_service && !changes_existing_job) + continue; + + if (stops_running_service) + log_debug("%s/%s would stop a running service.", j->unit->meta.id, job_type_to_string(j->type)); + + if (changes_existing_job) + log_debug("%s/%s would change existing job.", j->unit->meta.id, job_type_to_string(j->type)); + + /* Ok, let's get rid of this */ + log_debug("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) + continue; + + if (j->unit->meta.job) + job_free(j->unit->meta.job); + + j->unit->meta.job = j; + j->installed = true; + + /* 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); + } + + /* 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) { + 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. */ + 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)) >= 0) + break; + + if (r != -EAGAIN) { + log_debug("Requested transaction contains an unfixable cyclic ordering dependency: %s", strerror(-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)) >= 0) + break; + + if (r != -EAGAIN) { + log_debug("Requested transaction contains unmergable jobs: %s", strerror(-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)) < 0) { + log_debug("Requested transaction contradicts existing jobs: %s", strerror(-r)); + goto rollback; + } + + /* Tenth step: apply changes */ + if ((r = transaction_apply(m)) < 0) { + log_debug("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; + int r; + + 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 ((r = 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, + 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) + return -EINVAL; + + if (!unit_job_is_applicable(unit, type)) + 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)) + return -ENOMEM; + + if (is_new) { + /* 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, NULL)) < 0 && r != -EBADR) + goto fail; + + 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, NULL)) < 0 && r != -EBADR) + log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, strerror(-r)); + + SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_WANTS], i) + if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, false, false, NULL)) < 0) + log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, strerror(-r)); + + 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, NULL)) < 0 && r != -EBADR) + goto fail; + + 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, NULL)) < 0 && r != -EBADR) + log_warning("Cannot add dependency job for unit %s, ignoring: %s", dep->meta.id, strerror(-r)); + + SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_CONFLICTS], i) + if ((r = transaction_add_job_and_dependencies(m, JOB_STOP, dep, ret, true, override, NULL)) < 0 && r != -EBADR) + goto fail; + + } 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, NULL)) < 0 && r != -EBADR) + goto fail; + } + + /* 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_active_state(u) == UNIT_INACTIVE) + 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, 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, 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) + return -EINVAL; + + log_debug("Trying to enqueue job %s/%s", unit->meta.id, job_type_to_string(type)); + + if ((r = transaction_add_job_and_dependencies(m, type, unit, NULL, true, override, &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)) < 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, 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, &unit)) < 0) + return r; + + return manager_add_job(m, type, unit, mode, override, _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, 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)) + return -EINVAL; + + if (!name) + name = file_name_from_path(path); + + if (!unit_name_is_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, 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, _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_dispatch_sigchld(Manager *m) { + assert(m); + + for (;;) { + siginfo_t si; + Unit *u; + + 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 %llu (%s)", (unsigned long long) si.si_pid, strna(name)); + free(name); + } + + /* 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 %llu died (code=%s, status=%i/%s)", + (long 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) : strsignal(si.si_status))); + + if (!(u = hashmap_remove(m->watch_pids, UINT32_TO_PTR(si.si_pid)))) + continue; + + log_debug("Child %llu belongs to %s", (long long unsigned) si.si_pid, u->meta.id); + + UNIT_VTABLE(u)->sigchld_event(u, si.si_pid, si.si_code, si.si_status); + } + + return 0; +} + +static void manager_start_target(Manager *m, const char *name) { + int r; + + if ((r = manager_add_job_by_name(m, JOB_START, name, JOB_REPLACE, true, NULL)) < 0) + log_error("Failed to enqueue %s job: %s", name, strerror(-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 == EAGAIN) + break; + + return -errno; + } + + switch (sfsi.ssi_signo) { + + case SIGCHLD: + sigchld = true; + break; + + case SIGTERM: + if (m->running_as == MANAGER_INIT) + /* This is for compatibility with the + * original sysvinit */ + m->exit_code = MANAGER_REEXECUTE; + else + m->exit_code = MANAGER_EXIT; + + return 0; + + case SIGINT: + if (m->running_as == MANAGER_INIT) { + manager_start_target(m, SPECIAL_CTRL_ALT_DEL_TARGET); + break; + } + + m->exit_code = MANAGER_EXIT; + return 0; + + case SIGWINCH: + if (m->running_as == MANAGER_INIT) + manager_start_target(m, SPECIAL_KBREQUEST_TARGET); + + /* This is a nop on non-init */ + break; + + case SIGPWR: + if (m->running_as == MANAGER_INIT) + manager_start_target(m, SPECIAL_SIGPWR_TARGET); + + /* 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_system(m); + bus_init_api(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); + } + + break; + } + + case SIGUSR2: + manager_dump_units(m, stdout, "\t"); + manager_dump_jobs(m, stdout, "\t"); + break; + + case SIGHUP: + m->exit_code = MANAGER_RELOAD; + break; + + default: + log_info("Got unhandled signal <%s>.", strsignal(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); + + 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_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_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; + } + + UNIT_VTABLE(w->data.unit)->timer_event(w->data.unit, v, w); + break; + } + + case WATCH_MOUNT: + /* Some mount table change, intended for the mount subsystem */ + mount_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: + 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; + + 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 ((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; +} + +static bool manager_utmp_good(Manager *m) { + int r; + + assert(m); + + if ((r = mount_path_is_mounted(m, _PATH_UTMPX)) <= 0) { + + if (r < 0) + log_warning("Failed to determine whether " _PATH_UTMPX " is mounted: %s", strerror(-r)); + + return false; + } + + return true; +} + +void manager_write_utmp_reboot(Manager *m) { + int r; + + assert(m); + + if (m->utmp_reboot_written) + return; + + if (m->running_as != MANAGER_INIT) + return; + + if (!manager_utmp_good(m)) + return; + + if ((r = utmp_put_reboot(m->boot_timestamp)) < 0) { + + if (r != -ENOENT && r != -EROFS) + log_warning("Failed to write utmp/wtmp: %s", strerror(-r)); + + return; + } + + m->utmp_reboot_written = true; +} + +void manager_write_utmp_runlevel(Manager *m, Unit *u) { + int runlevel, r; + + assert(m); + assert(u); + + if (u->meta.type != UNIT_TARGET) + return; + + if (m->running_as != MANAGER_INIT) + return; + + if (!manager_utmp_good(m)) + return; + + if ((runlevel = target_get_runlevel(TARGET(u))) <= 0) + return; + + if ((r = utmp_put_runlevel(0, runlevel, 0)) < 0) { + + if (r != -ENOENT && r != -EROFS) + log_warning("Failed to write utmp/wtmp: %s", strerror(-r)); + } +} + +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(FILE **_f) { + char *path; + mode_t saved_umask; + int fd; + FILE *f; + + assert(_f); + + if (asprintf(&path, "/dev/shm/systemd-%u.dump-XXXXXX", (unsigned) 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); + + 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..."); + + for (;;) { + Unit *u; + char name[UNIT_NAME_MAX+2]; + + /* Start marker */ + if (!fgets(name, sizeof(name), f)) { + if (feof(f)) + break; + + return -errno; + } + + char_array_0(name); + + if ((r = manager_load_unit(m, strstrip(name), NULL, &u)) < 0) + return r; + + if ((r = unit_deserialize(u, f, fds)) < 0) + return r; + } + + if (ferror(f)) + return -EIO; + + return 0; +} + +int manager_reload(Manager *m) { + int r, q; + FILE *f; + FDSet *fds; + + assert(m); + + if ((r = manager_open_serialization(&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); + + /* 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; + +finish: + if (f) + fclose(f); + + if (fds) + fdset_free(fds); + + return r; +} + +static const char* const manager_running_as_table[_MANAGER_RUNNING_AS_MAX] = { + [MANAGER_INIT] = "init", + [MANAGER_SYSTEM] = "system", + [MANAGER_SESSION] = "session" +}; + +DEFINE_STRING_TABLE_LOOKUP(manager_running_as, ManagerRunningAs); |