#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 <sys/poll.h>
#include "manager.h"
#include "hashmap.h"
#include "macro.h"
#include "strv.h"
-#include "load-fragment.h"
+#include "log.h"
+#include "util.h"
+
+static int manager_setup_signals(Manager *m) {
+ sigset_t mask;
+ struct epoll_event ev;
+
+ assert(m);
+
+ assert_se(reset_all_signal_handlers() == 0);
+
+ assert_se(sigemptyset(&mask) == 0);
+ assert_se(sigaddset(&mask, SIGCHLD) == 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, SIGTERM) == 0);
+ assert_se(sigaddset(&mask, SIGHUP) == 0);
+ assert_se(sigaddset(&mask, SIGUSR1) == 0);
+ assert_se(sigaddset(&mask, SIGUSR2) == 0);
+ assert_se(sigaddset(&mask, SIGPIPE) == 0);
+ 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;
+
+ return 0;
+}
Manager* manager_new(void) {
Manager *m;
if (!(m = new0(Manager, 1)))
return NULL;
- if (!(m->names = hashmap_new(string_hash_func, string_compare_func)))
+ m->signal_watch.fd = m->mount_watch.fd = m->udev_watch.fd = m->epoll_fd = -1;
+
+ 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->jobs_to_add = hashmap_new(trivial_hash_func, trivial_compare_func)))
+ if (!(m->transaction_jobs = hashmap_new(trivial_hash_func, trivial_compare_func)))
goto fail;
- if (!(m->jobs_to_remove = set_new(trivial_hash_func, trivial_compare_func)))
+ if (!(m->watch_pids = hashmap_new(trivial_hash_func, trivial_compare_func)))
+ goto fail;
+
+ if ((m->epoll_fd = epoll_create1(EPOLL_CLOEXEC)) < 0)
+ goto fail;
+
+ if (manager_setup_signals(m) < 0)
goto fail;
return m;
}
void manager_free(Manager *m) {
- Name *n;
+ UnitType c;
+ Unit *u;
+ Job *j;
assert(m);
- while ((n = hashmap_first(m->names)))
- name_free(n);
+ while ((j = hashmap_first(m->transaction_jobs)))
+ job_free(j);
- hashmap_free(m->names);
- hashmap_free(m->jobs);
+ while ((u = hashmap_first(m->units)))
+ unit_free(u);
+
+ for (c = 0; c < _UNIT_TYPE_MAX; c++)
+ if (unit_vtable[c]->shutdown)
+ unit_vtable[c]->shutdown(m);
- /* FIXME: This is incomplete */
+ hashmap_free(m->units);
+ hashmap_free(m->jobs);
+ hashmap_free(m->transaction_jobs);
+ hashmap_free(m->watch_pids);
- hashmap_free(m->jobs_to_add);
- set_free(m->jobs_to_remove);
+ if (m->epoll_fd >= 0)
+ close_nointr(m->epoll_fd);
+ if (m->signal_watch.fd >= 0)
+ close_nointr(m->signal_watch.fd);
free(m);
}
-int manager_add_job(Manager *m, JobType type, Name *name, JobMode mode, Job **_ret) {
- Job *ret, *other;
- void *state;
- Name *dep;
+int manager_coldplug(Manager *m) {
int r;
+ UnitType c;
+ Iterator i;
+ Unit *u;
+ char *k;
assert(m);
- assert(type < _JOB_TYPE_MAX);
- assert(name);
- assert(mode < _JOB_MODE_MAX);
- assert(_ret);
-
- /* Check for conflicts, first against the jobs we shall
- * create */
- if ((other = hashmap_get(m->jobs_to_add, name))) {
- if (other->type != type)
- return -EEXIST;
+ /* First, 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 ((r = unit_vtable[c]->enumerate(m)) < 0)
+ return r;
- } else if (name->meta.job) {
+ manager_dispatch_load_queue(m);
- if (name->meta.job->type != type) {
+ /* Then, let's set up their initial state. */
+ HASHMAP_FOREACH_KEY(u, k, m->units, i) {
- if (mode == JOB_FAIL)
- return -EEXIST;
+ /* ignore aliases */
+ if (unit_id(u) != k)
+ continue;
- if ((r = set_put(m->jobs_to_remove, name->meta.job)) < 0)
+ if (UNIT_VTABLE(u)->coldplug)
+ if ((r = UNIT_VTABLE(u)->coldplug(u)) < 0)
return r;
- }
}
- if (!(ret = job_new(m, type, name)))
- return -ENOMEM;
+ return 0;
+}
- if ((r = hashmap_put(m->jobs_to_add, name, ret)) < 0)
- goto fail;
+static void transaction_delete_job(Manager *m, Job *j) {
+ assert(m);
+ assert(j);
- if (type == JOB_START || type == JOB_VERIFY_STARTED || type == JOB_RESTART_FINISH) {
- SET_FOREACH(dep, ret->name->meta.dependencies[NAME_REQUIRES], state)
- if ((r = manager_add_job(m, type, dep, mode, NULL)) < 0)
- goto fail;
- SET_FOREACH(dep, ret->name->meta.dependencies[NAME_SOFT_REQUIRES], state)
- if ((r = manager_add_job(m, type, dep, JOB_FAIL, NULL)) < 0)
- goto fail;
- SET_FOREACH(dep, ret->name->meta.dependencies[NAME_WANTS], state)
- if ((r = manager_add_job(m, type, dep, JOB_FAIL, NULL)) < 0)
- goto fail;
- SET_FOREACH(dep, ret->name->meta.dependencies[NAME_REQUISITE], state)
- if ((r = manager_add_job(m, JOB_VERIFY_STARTED, dep, mode, NULL)) < 0)
- goto fail;
- SET_FOREACH(dep, ret->name->meta.dependencies[NAME_SOFT_REQUISITE], state)
- if ((r = manager_add_job(m, JOB_VERIFY_STARTED, dep, JOB_FAIL, NULL)) < 0)
- goto fail;
- SET_FOREACH(dep, ret->name->meta.dependencies[NAME_CONFLICTS], state)
- if ((r = manager_add_job(m, type, dep, mode, NULL)) < 0)
- goto fail;
-
- } else if (type == JOB_STOP || type == JOB_RESTART || type == JOB_TRY_RESTART) {
-
- SET_FOREACH(dep, ret->name->meta.dependencies[NAME_REQUIRED_BY], state)
- if ((r = manager_add_job(m, type, dep, mode, NULL)) < 0)
- goto fail;
- }
+ /* Deletes one job from the transaction */
- if (_ret)
- *_ret = ret;
+ manager_transaction_unlink_job(m, j);
- return 0;
+ if (!j->installed)
+ job_free(j);
+}
-fail:
- job_free(ret);
+static void transaction_delete_unit(Manager *m, Unit *u) {
+ Job *j;
- return r;
+ /* Deletes all jobs associated with a certain unit from the
+ * transaction */
+
+ while ((j = hashmap_get(m->transaction_jobs, u)))
+ transaction_delete_job(m, j);
}
+static void transaction_clean_dependencies(Manager *m) {
+ Iterator i;
+ Job *j;
-Job *manager_get_job(Manager *m, uint32_t id) {
assert(m);
- return hashmap_get(m->jobs, UINT32_TO_PTR(id));
+ /* 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);
}
-Name *manager_get_name(Manager *m, const char *name) {
+static void transaction_abort(Manager *m) {
+ Job *j;
+
assert(m);
- assert(name);
- return hashmap_get(m->names, name);
+ while ((j = hashmap_first(m->transaction_jobs)))
+ if (j->installed)
+ transaction_delete_job(m, j);
+ else
+ job_free(j);
+
+ assert(hashmap_isempty(m->transaction_jobs));
+
+ transaction_clean_dependencies(m);
}
-static int verify_type(Name *name) {
- char *n;
- void *state;
+static void transaction_find_jobs_that_matter_to_anchor(Manager *m, Job *j, unsigned generation) {
+ JobDependency *l;
- assert(name);
+ assert(m);
- /* Checks that all aliases of this name have the same and valid type */
+ /* 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. */
- SET_FOREACH(n, name->meta.names, state) {
- NameType t;
+ if (j)
+ l = j->subject_list;
+ else
+ l = m->transaction_anchor;
- if ((t = name_type_from_string(n)) == _NAME_TYPE_INVALID)
- return -EINVAL;
+ LIST_FOREACH(subject, l, l) {
+
+ /* This link does not matter */
+ if (!l->matters)
+ continue;
- if (name->meta.type == _NAME_TYPE_INVALID) {
- name->meta.type = t;
+ /* 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->forced = j->forced || other->forced;
+
+ 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);
+}
+
+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("Try to fix job merging by deleting job %s/%s", unit_id(d->unit), job_type_to_string(d->type));
+ transaction_delete_job(m, d);
+ return 0;
}
- if (name->meta.type != t)
- return -EINVAL;
+ 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;
+ }
}
- if (name->meta.type == _NAME_TYPE_INVALID)
- return -EINVAL;
+ /* 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 int service_load_sysv(Service *s) {
- assert(s);
+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;
- /* Load service data from SysV init scripts, preferably with
- * LSB headers ... */
+ 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 cycle on %s/%s", unit_id(j->unit), 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", unit_id(j->unit), job_type_to_string(j->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", unit_id(k->unit), 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 name_load_fstab(Name *n) {
- assert(n);
- assert(n->meta.type == NAME_MOUNT || n->meta.type == NAME_AUTOMOUNT);
+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. */
- /* Load mount data from /etc/fstab */
+ HASHMAP_FOREACH(j, m->transaction_jobs, i)
+ if ((r = transaction_verify_order_one(m, j, NULL, (*generation)++)) < 0)
+ return r;
return 0;
}
-static int snapshot_load(Snapshot *s) {
- assert(s);
+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", unit_id(j->unit), job_type_to_string(j->type));
+ transaction_delete_job(m, j);
+ again = true;
+ break;
+ }
+
+ } while (again);
+}
+
+static int transaction_is_destructive(Manager *m, JobMode mode) {
+ 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) {
- /* Load snapshots from disk */
+ /* 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 int name_load_dropin(Name *n) {
- assert(n);
+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;
- /* Load dependencies from drop-in directories */
+ 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.", unit_id(j->unit), job_type_to_string(j->type));
+
+ if (changes_existing_job)
+ log_debug("%s/%s would change existing job.", unit_id(j->unit), job_type_to_string(j->type));
+
+ /* Ok, let's get rid of this */
+ log_debug("Deleting %s/%s to minimize impact.", unit_id(j->unit), job_type_to_string(j->type));
+
+ transaction_delete_job(m, j);
+ again = true;
+ break;
+ }
+
+ if (again)
+ break;
+ }
+
+ } while (again);
+}
+
+static int transaction_apply(Manager *m, JobMode mode) {
+ 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_schedule_run(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 load(Name *name) {
+static int transaction_activate(Manager *m, JobMode mode) {
int r;
+ unsigned generation = 1;
- assert(name);
+ assert(m);
- if (name->meta.state != NAME_STUB)
- return 0;
+ /* This applies the changes recorded in transaction_jobs to
+ * the actual list of jobs, if possible. */
- if ((r = verify_type(name)) < 0)
- return r;
+ /* First step: figure out which jobs matter */
+ transaction_find_jobs_that_matter_to_anchor(m, NULL, generation++);
- if (name->meta.type == NAME_SERVICE) {
+ /* 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);
- /* Load a .service file */
- if ((r = name_load_fragment(name)) == 0)
- goto finish;
+ for (;;) {
+ /* Third step: Let's remove unneeded jobs that might
+ * be lurking. */
+ transaction_collect_garbage(m);
- /* Load a classic init script */
- if (r == -ENOENT)
- if ((r = service_load_sysv(SERVICE(name))) == 0)
- goto finish;
+ /* Fourth step: verify order makes sense and correct
+ * cycles if necessary and possible */
+ if ((r = transaction_verify_order(m, &generation)) >= 0)
+ break;
- } else if (name->meta.type == NAME_MOUNT ||
- name->meta.type == NAME_AUTOMOUNT) {
+ 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... */
+ }
- if ((r = name_load_fstab(name)) == 0)
- goto finish;
+ for (;;) {
+ /* Fifth step: let's drop unmergeable entries if
+ * necessary and possible, merge entries we can
+ * merge */
+ if ((r = transaction_merge_jobs(m)) >= 0)
+ break;
- } else if (name->meta.type == NAME_SNAPSHOT) {
+ if (r != -EAGAIN) {
+ log_debug("Requested transaction contains unmergable jobs: %s", strerror(-r));
+ goto rollback;
+ }
- if ((r = snapshot_load(SNAPSHOT(name))) == 0)
- goto finish;
+ /* Sixth step: an entry got dropped, let's garbage
+ * collect its dependencies. */
+ transaction_collect_garbage(m);
- } else {
- if ((r = name_load_fragment(name)) == 0)
- goto finish;
+ /* Let's see if the resulting transaction still has
+ * unmergeable entries ... */
}
- name->meta.state = NAME_FAILED;
+ /* Seventh step: check whether we can actually apply this */
+ if (mode == JOB_FAIL)
+ if ((r = transaction_is_destructive(m, mode)) < 0) {
+ log_debug("Requested transaction contradicts existing jobs: %s", strerror(-r));
+ goto rollback;
+ }
+
+ /* Eights step: apply changes */
+ if ((r = transaction_apply(m, mode)) < 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 force, 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. */
-finish:
- if ((r = name_load_dropin(name)) < 0)
+ 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->forced = force;
+
+ 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;
+
+ return j;
+}
+
+void manager_transaction_unlink_job(Manager *m, Job *j) {
+ 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) {
+ log_debug("Deleting job %s/%s as dependency of job %s/%s",
+ unit_id(other->unit), job_type_to_string(other->type),
+ unit_id(j->unit), job_type_to_string(j->type));
+ transaction_delete_job(m, other);
+ }
+ }
+}
+
+static int transaction_add_job_and_dependencies(Manager *m, JobType type, Unit *unit, Job *by, bool matters, bool force, 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, force, &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, force, NULL)) < 0 && r != -EBADR)
+ goto fail;
+ SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_SOFT_REQUIRES], i)
+ if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, !force, force, NULL)) < 0 && r != -EBADR)
+ goto fail;
+ SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_WANTS], i)
+ if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, false, force, NULL)) < 0 && r != -EBADR)
+ goto fail;
+ SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_REQUISITE], i)
+ if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_ACTIVE, dep, ret, true, force, NULL)) < 0 && r != -EBADR)
+ goto fail;
+ SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_SOFT_REQUISITE], i)
+ if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_ACTIVE, dep, ret, !force, force, NULL)) < 0 && r != -EBADR)
+ goto fail;
+ SET_FOREACH(dep, ret->unit->meta.dependencies[UNIT_CONFLICTS], i)
+ if ((r = transaction_add_job_and_dependencies(m, JOB_STOP, dep, ret, true, force, 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, force, NULL)) < 0 && r != -EBADR)
+ goto fail;
+ }
+
+ /* JOB_VERIFY_STARTED, JOB_RELOAD require no dependency handling */
+ }
+
+ return 0;
+
+fail:
+ return r;
+}
+
+int manager_add_job(Manager *m, JobType type, Unit *unit, JobMode mode, bool force, Job **_ret) {
+ int r;
+ Job *ret;
+
+ assert(m);
+ assert(type < _JOB_TYPE_MAX);
+ assert(unit);
+ assert(mode < _JOB_MODE_MAX);
+
+ log_debug("Trying to enqueue job %s/%s", unit_id(unit), job_type_to_string(type));
+
+ if ((r = transaction_add_job_and_dependencies(m, type, unit, NULL, true, force, &ret))) {
+ transaction_abort(m);
+ return r;
+ }
+
+ if ((r = transaction_activate(m, mode)) < 0)
return r;
- name->meta.state = NAME_LOADED;
+ log_debug("Enqueued job %s/%s", unit_id(unit), job_type_to_string(type));
+
+ if (_ret)
+ *_ret = ret;
+
return 0;
}
-static int dispatch_load_queue(Manager *m) {
+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);
+}
+
+void manager_dispatch_load_queue(Manager *m) {
Meta *meta;
assert(m);
/* Make sure we are not run recursively */
if (m->dispatching_load_queue)
- return 0;
+ return;
m->dispatching_load_queue = true;
- /* Dispatches the load queue. Takes a name from the queue and
+ /* 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)) {
- load(NAME(meta));
- LIST_REMOVE(Meta, m->load_queue, meta);
+ assert(meta->in_load_queue);
+
+ unit_load(UNIT(meta));
}
m->dispatching_load_queue = false;
-
- return 0;
}
-int manager_load_name(Manager *m, const char *name, Name **_ret) {
- Name *ret;
- NameType t;
+int manager_load_unit(Manager *m, const char *path, Unit **_ret) {
+ Unit *ret;
int r;
- char *n;
+ const char *name;
assert(m);
- assert(name);
+ assert(path);
assert(_ret);
- if (!name_is_valid(name))
- return -EINVAL;
-
/* This will load the service information files, but not actually
- * start any services or anything */
+ * start any services or anything. */
- if ((ret = manager_get_name(m, name)))
- goto finish;
+ name = file_name_from_path(path);
- if ((t = name_type_from_string(name)) == _NAME_TYPE_INVALID)
- return -EINVAL;
+ if ((ret = manager_get_unit(m, name))) {
+ *_ret = ret;
+ return 0;
+ }
- if (!(ret = name_new(m)))
+ if (!(ret = unit_new(m)))
return -ENOMEM;
- ret->meta.type = t;
+ if (is_path(path)) {
+ if (!(ret->meta.load_path = strdup(path))) {
+ unit_free(ret);
+ return -ENOMEM;
+ }
+ }
- if (!(n = strdup(name))) {
- name_free(ret);
- return -ENOMEM;
+ if ((r = unit_add_name(ret, name)) < 0) {
+ unit_free(ret);
+ return r;
}
- if (set_put(ret->meta.names, n) < 0) {
- name_free(ret);
- free(n);
- return -ENOMEM;
+ unit_add_to_load_queue(ret);
+ manager_dispatch_load_queue(m);
+
+ *_ret = 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 (unit_id(u) == 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);
+}
+
+void manager_dispatch_run_queue(Manager *m) {
+ Job *j;
+
+ if (m->dispatching_run_queue)
+ return;
+
+ m->dispatching_run_queue = true;
+
+ while ((j = m->run_queue)) {
+ assert(j->installed);
+ assert(j->in_run_queue);
+
+ job_run_and_invalidate(j);
}
- if ((r = name_link(ret)) < 0) {
- name_free(ret);
- return r;
+ m->dispatching_run_queue = false;
+}
+
+static int manager_dispatch_sigchld(Manager *m) {
+ assert(m);
+
+ log_debug("dispatching SIGCHLD");
+
+ for (;;) {
+ siginfo_t si;
+ Unit *u;
+
+ zero(si);
+ if (waitid(P_ALL, 0, &si, WEXITED|WNOHANG) < 0) {
+
+ if (errno == ECHILD)
+ break;
+
+ return -errno;
+ }
+
+ if (si.si_pid == 0)
+ break;
+
+ 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)", (long long unsigned) si.si_pid, sigchld_code_to_string(si.si_code), si.si_status);
+
+ if (!(u = hashmap_remove(m->watch_pids, UINT32_TO_PTR(si.si_pid))))
+ continue;
+
+ UNIT_VTABLE(u)->sigchld_event(u, si.si_pid, si.si_code, si.si_status);
}
- /* At this point the new entry is created and linked. However,
- * not loaded. Now load this entry and all its dependencies
- * recursively */
+ return 0;
+}
+
+static int manager_process_signal_fd(Manager *m, bool *quit) {
+ ssize_t n;
+ struct signalfd_siginfo sfsi;
+ bool sigchld = false;
- dispatch_load_queue(m);
+ assert(m);
-finish:
+ 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 SIGINT:
+ case SIGTERM:
+ *quit = true;
+ return 0;
+
+ default:
+ log_info("Got unhandled signal <%s>.", strsignal(sfsi.ssi_signo));
+ }
+ }
+
+ if (sigchld)
+ return manager_dispatch_sigchld(m);
- *_ret = ret;
return 0;
}
+
+static int process_event(Manager *m, struct epoll_event *ev, bool *quit) {
+ 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, quit)) < 0)
+ return r;
+
+ break;
+
+ case WATCH_FD:
+
+ /* Some fd event, to be dispatched to the units */
+ UNIT_VTABLE(w->unit)->fd_event(w->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(ev->data.fd, &v, sizeof(v))) != sizeof(v)) {
+
+ if (k < 0 && (errno == EINTR || errno == EAGAIN))
+ break;
+
+ return k < 0 ? -errno : -EIO;
+ }
+
+ UNIT_VTABLE(w->unit)->timer_event(w->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;
+
+ default:
+ assert_not_reached("Unknown epoll event type.");
+ }
+
+ return 0;
+}
+
+int manager_loop(Manager *m) {
+ int r;
+ bool quit = false;
+
+ assert(m);
+
+ for (;;) {
+ struct epoll_event event;
+ int n;
+
+ manager_dispatch_run_queue(m);
+
+ 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, &quit)) < 0)
+ return r;
+
+ if (quit)
+ return 0;
+ }
+}