X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=manager.c;h=cb447568917026a22ceabc76bfa81c4065f86e44;hp=da2d4334746881728ebebdb3d77c1fb5efd510d7;hb=6be1e7d538e12f4e5c79c1271dba90e66726d8fd;hpb=9ea024f6b5a9626ddabeb4c4d4385481b52d211e diff --git a/manager.c b/manager.c index da2d43347..cb4475689 100644 --- a/manager.c +++ b/manager.c @@ -1,14 +1,244 @@ /*-*- 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 . +***/ + #include #include #include +#include +#include +#include +#include +#include +#include #include "manager.h" #include "hashmap.h" #include "macro.h" #include "strv.h" #include "log.h" +#include "util.h" +#include "ratelimit.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; +} + +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"))) + config_dirs = strv_split(e, ":"); + else + config_dirs = strv_new("/etc/xdg", NULL); + + if (!config_dirs) + goto fail; + + 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; + } + + /* FIXME: This should probably look for MANAGER_INIT, and exclude MANAGER_SYSTEM */ + if (m->running_as != MANAGER_SESSION) { + /* /etc/init.d/ compativility 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; + } + } + + strv_uniq(m->unit_path); + strv_uniq(m->sysvinit_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."); + + return 0; +} Manager* manager_new(void) { Manager *m; @@ -16,7 +246,22 @@ Manager* manager_new(void) { if (!(m = new0(Manager, 1))) return NULL; - if (!(m->names = hashmap_new(string_hash_func, string_compare_func))) + if (getpid() == 1) + m->running_as = MANAGER_INIT; + else if (getuid() == 0) + m->running_as = MANAGER_SYSTEM; + else + m->running_as = MANAGER_SESSION; + + log_debug("systemd running in %s mode.", manager_running_as_to_string(m->running_as)); + + m->signal_watch.fd = m->mount_watch.fd = m->udev_watch.fd = m->epoll_fd = -1; + m->current_job_id = 1; /* start as id #1, so that we can leave #0 around as "null-like" value */ + + if (manager_find_paths(m) < 0) + 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))) @@ -25,6 +270,19 @@ Manager* manager_new(void) { 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->epoll_fd = epoll_create1(EPOLL_CLOEXEC)) < 0) + goto fail; + + if (manager_setup_signals(m) < 0) + goto fail; + + /* FIXME: this should be called only when the D-Bus bus daemon is running */ + if (bus_init(m) < 0) + goto fail; + return m; fail: @@ -33,47 +291,127 @@ fail: } 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_steal_first(m->transaction_jobs))) + while ((j = hashmap_first(m->transaction_jobs))) job_free(j); - hashmap_free(m->names); + 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); + + bus_done(m); + + hashmap_free(m->units); hashmap_free(m->jobs); hashmap_free(m->transaction_jobs); + hashmap_free(m->watch_pids); + + if (m->epoll_fd >= 0) + close_nointr(m->epoll_fd); + if (m->signal_watch.fd >= 0) + close_nointr(m->signal_watch.fd); + + strv_free(m->unit_path); + strv_free(m->sysvinit_path); free(m); } +int manager_coldplug(Manager *m) { + int r; + UnitType c; + Iterator i; + Unit *u; + char *k; + + assert(m); + + /* 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; + + manager_dispatch_load_queue(m); + + /* Then, let's set up their initial state. */ + HASHMAP_FOREACH_KEY(u, k, m->units, i) { + + /* ignore aliases */ + if (unit_id(u) != k) + continue; + + if (UNIT_VTABLE(u)->coldplug) + if ((r = UNIT_VTABLE(u)->coldplug(u)) < 0) + return r; + } + + return 0; +} + static void transaction_delete_job(Manager *m, Job *j) { assert(m); assert(j); + /* Deletes one job from the transaction */ + manager_transaction_unlink_job(m, j); - if (!j->linked) + 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); +} + +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->linked) + if (j->installed) transaction_delete_job(m, j); else job_free(j); assert(hashmap_isempty(m->transaction_jobs)); - assert(!m->transaction_anchor); + + transaction_clean_dependencies(m); } static void transaction_find_jobs_that_matter_to_anchor(Manager *m, Job *j, unsigned generation) { @@ -81,13 +419,23 @@ static void transaction_find_jobs_that_matter_to_anchor(Manager *m, Job *j, unsi assert(m); - for (l = j ? j->subject_list : m->transaction_anchor; l; l = l->subject_next) { + /* 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 name has already been marked */ + /* This unit has already been marked */ if (l->object->generation == generation) continue; @@ -98,56 +446,25 @@ static void transaction_find_jobs_that_matter_to_anchor(Manager *m, Job *j, unsi } } -static bool types_match(JobType a, JobType b, JobType c, JobType d) { - return - (a == c && b == d) || - (a == d && b == c); -} - -static int types_merge(JobType *a, JobType b) { - if (*a == b) - return 0; - - if (types_match(*a, b, JOB_START, JOB_VERIFY_STARTED)) - *a = JOB_START; - else if (types_match(*a, b, JOB_START, JOB_RELOAD) || - types_match(*a, b, JOB_START, JOB_RELOAD_OR_START) || - types_match(*a, b, JOB_VERIFY_STARTED, JOB_RELOAD_OR_START) || - types_match(*a, b, JOB_RELOAD, JOB_RELOAD_OR_START)) - *a = JOB_RELOAD_OR_START; - else if (types_match(*a, b, JOB_START, JOB_RESTART) || - types_match(*a, b, JOB_START, JOB_TRY_RESTART) || - types_match(*a, b, JOB_VERIFY_STARTED, JOB_RESTART) || - types_match(*a, b, JOB_RELOAD, JOB_RESTART) || - types_match(*a, b, JOB_RELOAD_OR_START, JOB_RESTART) || - types_match(*a, b, JOB_RELOAD_OR_START, JOB_TRY_RESTART) || - types_match(*a, b, JOB_RESTART, JOB_TRY_RESTART)) - *a = JOB_RESTART; - else if (types_match(*a, b, JOB_VERIFY_STARTED, JOB_RELOAD)) - *a = JOB_RELOAD; - else if (types_match(*a, b, JOB_VERIFY_STARTED, JOB_TRY_RESTART) || - types_match(*a, b, JOB_RELOAD, JOB_TRY_RESTART)) - *a = JOB_TRY_RESTART; - - return -EEXIST; -} - static void transaction_merge_and_delete_job(Manager *m, Job *j, Job *other, JobType t) { JobDependency *l, *last; assert(j); assert(other); - assert(j->name == other->name); - assert(!j->linked); + 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; - for (l = other->subject_list; l; l = l->subject_next) { + LIST_FOREACH(subject, l, other->subject_list) { assert(l->subject == other); l->subject = j; last = l; @@ -163,7 +480,7 @@ static void transaction_merge_and_delete_job(Manager *m, Job *j, Job *other, Job /* Patch us in as new owner of the JobDependency objects */ last = NULL; - for (l = other->object_list; l; l = l->object_next) { + LIST_FOREACH(object, l, other->object_list) { assert(l->object == other); l->object = j; last = l; @@ -183,23 +500,92 @@ static void transaction_merge_and_delete_job(Manager *m, Job *j, Job *other, Job 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; + } + + return -EINVAL; +} + static int transaction_merge_jobs(Manager *m) { Job *j; - void *state; + Iterator i; int r; assert(m); - HASHMAP_FOREACH(j, m->transaction_jobs, state) { + /* 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; - for (k = j->transaction_next; k; k = k->transaction_next) - if ((r = types_merge(&t, k->type)) < 0) - return r; + /* 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->linked) { + if (j->installed) { transaction_merge_and_delete_job(m, k, j, t); j = k; } else @@ -213,26 +599,55 @@ static int transaction_merge_jobs(Manager *m) { return 0; } +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) { - void *state; - Name *n; + 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. */ + * 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)) { - if (!k->matters_to_anchor) { - log_debug("Breaking order cycle by deleting job %s", name_id(k->name)); - transaction_delete_job(m, k); + + 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; } @@ -242,60 +657,55 @@ static int transaction_verify_order_one(Manager *m, Job *j, Job *from, unsigned break; } - return -ELOOP; + 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 both-ways, and - * hence can ignore NAME_AFTER */ - - SET_FOREACH(n, j->name->meta.dependencies[NAME_BEFORE], state) { + /* 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; - if (!(o = hashmap_get(m->transaction_jobs, n))) - if (!(o = n->meta.job)) + /* 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) { - bool again; + Job *j; + int r; + Iterator i; + assert(m); assert(generation); - do { - Job *j; - int r; - void *state; - - again = false; + /* 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, state) { - - /* Assume merged */ - assert(!j->transaction_next); - assert(!j->transaction_prev); - - if ((r = transaction_verify_order_one(m, j, NULL, (*generation)++)) < 0) { - - /* There was a cycleq, but it was fixed, - * we need to restart our algorithm */ - if (r == -EAGAIN) { - again = true; - break; - } - - return r; - } - } - } while (again); + HASHMAP_FOREACH(j, m->transaction_jobs, i) + if ((r = transaction_verify_order_one(m, j, NULL, (*generation)++)) < 0) + return r; return 0; } @@ -305,18 +715,19 @@ static void transaction_collect_garbage(Manager *m) { assert(m); + /* Drop jobs that are not required by any other job */ + do { - void *state; + Iterator i; Job *j; again = false; - HASHMAP_FOREACH(j, m->transaction_jobs, state) { + HASHMAP_FOREACH(j, m->transaction_jobs, i) { if (j->object_list) continue; - log_debug("Garbage collecting job %s", name_id(j->name)); - + 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; @@ -326,7 +737,7 @@ static void transaction_collect_garbage(Manager *m) { } static int transaction_is_destructive(Manager *m, JobMode mode) { - void *state; + Iterator i; Job *j; assert(m); @@ -334,20 +745,89 @@ static int transaction_is_destructive(Manager *m, JobMode mode) { /* Checks whether applying this transaction means that * existing jobs would be replaced */ - HASHMAP_FOREACH(j, m->transaction_jobs, state) - if (j->name->meta.job && j->name->meta.job != j) + 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.", 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) { - void *state; + Iterator i; Job *j; int r; - HASHMAP_FOREACH(j, m->transaction_jobs, state) { - if (j->linked) + /* 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) @@ -355,14 +835,14 @@ static int transaction_apply(Manager *m, JobMode mode) { } while ((j = hashmap_steal_first(m->transaction_jobs))) { - if (j->linked) + if (j->installed) continue; - if (j->name->meta.job) - job_free(j->name->meta.job); + if (j->unit->meta.job) + job_free(j->unit->meta.job); - j->name->meta.job = j; - j->linked = true; + j->unit->meta.job = j; + j->installed = true; /* We're fully installed. Now let's free data we don't * need anymore. */ @@ -370,18 +850,19 @@ static int transaction_apply(Manager *m, JobMode mode) { assert(!j->transaction_next); assert(!j->transaction_prev); - while (j->subject_list) - job_dependency_free(j->subject_list); - while (j->object_list) - job_dependency_free(j->object_list); + 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, state) { - if (j->linked) + HASHMAP_FOREACH(j, m->transaction_jobs, i) { + if (j->installed) continue; hashmap_remove(m->jobs, UINT32_TO_PTR(j->id)); @@ -390,7 +871,6 @@ rollback: return r; } - static int transaction_activate(Manager *m, JobMode mode) { int r; unsigned generation = 1; @@ -403,25 +883,62 @@ static int transaction_activate(Manager *m, JobMode mode) { /* First step: figure out which jobs matter */ transaction_find_jobs_that_matter_to_anchor(m, NULL, generation++); - /* Second step: let's merge entries we can merge */ - if ((r = transaction_merge_jobs(m)) < 0) - goto rollback; + /* 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: verify order makes sense */ - if ((r = transaction_verify_order(m, &generation)) < 0) - goto rollback; + for (;;) { + /* Third step: Let's remove unneeded jobs that might + * be lurking. */ + transaction_collect_garbage(m); - /* Third step: do garbage colletion */ - transaction_collect_garbage(m); + /* Fourth step: verify order makes sense and correct + * cycles if necessary and possible */ + if ((r = transaction_verify_order(m, &generation)) >= 0) + break; - /* Fourth step: check whether we can actually apply this */ + 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 (;;) { + /* Fifth 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; + } + + /* Sixth 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 ... */ + } + + /* Seventh step: check whether we can actually apply this */ if (mode == JOB_FAIL) - if ((r = transaction_is_destructive(m, mode)) < 0) + if ((r = transaction_is_destructive(m, mode)) < 0) { + log_debug("Requested transaction contradicts existing jobs: %s", strerror(-r)); goto rollback; + } - /* Fifth step: apply changes */ - if ((r = transaction_apply(m, mode)) < 0) + /* 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); @@ -433,21 +950,21 @@ rollback: return r; } -static Job* transaction_add_one_job(Manager *m, JobType type, Name *name, bool *is_new) { +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(name); + 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, name); + f = hashmap_get(m->transaction_jobs, unit); - for (j = f; j; j = j->transaction_next) { - assert(j->name == name); + LIST_FOREACH(transaction, j, f) { + assert(j->unit == unit); if (j->type == type) { if (is_new) @@ -456,24 +973,22 @@ static Job* transaction_add_one_job(Manager *m, JobType type, Name *name, bool * } } - if (name->meta.job && name->meta.job->type == type) - j = name->meta.job; - else if (!(j = job_new(m, type, name))) + if (unit->meta.job && unit->meta.job->type == type) + j = unit->meta.job; + else if (!(j = job_new(m, type, unit))) return NULL; - if ((r = hashmap_replace(m->transaction_jobs, name, j)) < 0) { - job_free(j); - return NULL; - } - - j->transaction_next = f; - - if (f) - f->transaction_prev = j; - 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; @@ -488,9 +1003,9 @@ void manager_transaction_unlink_job(Manager *m, Job *j) { if (j->transaction_prev) j->transaction_prev->transaction_next = j->transaction_next; else if (j->transaction_next) - hashmap_replace(m->transaction_jobs, j->name, j->transaction_next); + hashmap_replace(m->transaction_jobs, j->unit, j->transaction_next); else - hashmap_remove_value(m->transaction_jobs, j->name, j); + hashmap_remove_value(m->transaction_jobs, j->unit, j); if (j->transaction_next) j->transaction_next->transaction_prev = j->transaction_prev; @@ -506,28 +1021,33 @@ void manager_transaction_unlink_job(Manager *m, Job *j) { job_dependency_free(j->object_list); if (other) { - log_debug("Deleting job %s as dependency of job %s", name_id(other->name), name_id(j->name)); + 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, Name *name, Job *by, bool matters, bool force, Job **_ret) { +static int transaction_add_job_and_dependencies(Manager *m, JobType type, Unit *unit, Job *by, bool matters, bool force, Job **_ret) { Job *ret; - void *state; - Name *dep; + Iterator i; + Unit *dep; int r; bool is_new; assert(m); assert(type < _JOB_TYPE_MAX); - assert(name); + assert(unit); - if (name->meta.state != NAME_LOADED) + 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, name, &is_new))) + if (!(ret = transaction_add_one_job(m, type, unit, force, &is_new))) return -ENOMEM; /* Then, add a link to the job. */ @@ -537,51 +1057,56 @@ static int transaction_add_job_and_dependencies(Manager *m, JobType type, Name * if (is_new) { /* Finally, recursively add in all dependencies. */ if (type == JOB_START || type == JOB_RELOAD_OR_START) { - SET_FOREACH(dep, ret->name->meta.dependencies[NAME_REQUIRES], state) - if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, true, force, NULL)) < 0) + 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->name->meta.dependencies[NAME_SOFT_REQUIRES], state) - if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, !force, force, NULL)) < 0) + 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->name->meta.dependencies[NAME_WANTS], state) - if ((r = transaction_add_job_and_dependencies(m, JOB_START, dep, ret, false, force, NULL)) < 0) + 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->name->meta.dependencies[NAME_REQUISITE], state) - if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_STARTED, dep, ret, true, force, NULL)) < 0) + 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->name->meta.dependencies[NAME_SOFT_REQUISITE], state) - if ((r = transaction_add_job_and_dependencies(m, JOB_VERIFY_STARTED, dep, ret, !force, force, NULL)) < 0) + 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->name->meta.dependencies[NAME_CONFLICTS], state) - if ((r = transaction_add_job_and_dependencies(m, JOB_STOP, dep, ret, true, force, NULL)) < 0) + 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->name->meta.dependencies[NAME_REQUIRED_BY], state) - if ((r = transaction_add_job_and_dependencies(m, type, dep, ret, true, force, NULL)) < 0) + 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 */ } + if (_ret) + *_ret = ret; + return 0; fail: return r; } -int manager_add_job(Manager *m, JobType type, Name *name, JobMode mode, bool force, Job **_ret) { +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(name); + assert(unit); assert(mode < _JOB_MODE_MAX); - if ((r = transaction_add_job_and_dependencies(m, type, name, NULL, true, force, &ret))) { + 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)) < 0) { transaction_abort(m); return r; } @@ -589,6 +1114,8 @@ int manager_add_job(Manager *m, JobType type, Name *name, JobMode mode, bool for if ((r = transaction_activate(m, mode)) < 0) return r; + log_debug("Enqueued job %s/%s as %u", unit_id(unit), job_type_to_string(type), (unsigned) ret->id); + if (_ret) *_ret = ret; @@ -601,15 +1128,16 @@ Job *manager_get_job(Manager *m, uint32_t id) { return hashmap_get(m->jobs, UINT32_TO_PTR(id)); } -Name *manager_get_name(Manager *m, const char *name) { +Unit *manager_get_unit(Manager *m, const char *name) { assert(m); assert(name); - return hashmap_get(m->names, name); + return hashmap_get(m->units, name); } -static int dispatch_load_queue(Manager *m) { +unsigned manager_dispatch_load_queue(Manager *m) { Meta *meta; + unsigned n = 0; assert(m); @@ -619,96 +1147,85 @@ static int dispatch_load_queue(Manager *m) { 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)) { - name_load(NAME(meta)); - LIST_REMOVE(Meta, m->load_queue, meta); + assert(meta->in_load_queue); + + unit_load(UNIT(meta)); + n++; } m->dispatching_load_queue = false; - - return 0; + return n; } -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 */ - - if ((ret = manager_get_name(m, name))) - goto finish; - - if ((t = name_type_from_string(name)) == _NAME_TYPE_INVALID) - return -EINVAL; - - if (!(ret = name_new(m))) - return -ENOMEM; + * start any services or anything. */ - ret->meta.type = t; + name = file_name_from_path(path); - if (!(n = strdup(name))) { - name_free(ret); - return -ENOMEM; + if ((ret = manager_get_unit(m, name))) { + *_ret = ret; + return 0; } - if (set_put(ret->meta.names, n) < 0) { - name_free(ret); - free(n); + if (!(ret = unit_new(m))) return -ENOMEM; + + if (is_path(path)) { + if (!(ret->meta.fragment_path = strdup(path))) { + unit_free(ret); + return -ENOMEM; + } } - if ((r = name_link(ret)) < 0) { - name_free(ret); + if ((r = unit_add_name(ret, name)) < 0) { + unit_free(ret); return r; } - /* At this point the new entry is created and linked. However, - * not loaded. Now load this entry and all its dependencies - * recursively */ - - dispatch_load_queue(m); + unit_add_to_load_queue(ret); + unit_add_to_dbus_queue(ret); -finish: + manager_dispatch_load_queue(m); *_ret = ret; return 0; } void manager_dump_jobs(Manager *s, FILE *f, const char *prefix) { - void *state; + Iterator i; Job *j; assert(s); assert(f); - HASHMAP_FOREACH(j, s->jobs, state) + HASHMAP_FOREACH(j, s->jobs, i) job_dump(j, f, prefix); } -void manager_dump_names(Manager *s, FILE *f, const char *prefix) { - void *state; - Name *n; +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(n, t, s->names, state) - if (name_id(n) == t) - name_dump(n, f, prefix); + HASHMAP_FOREACH_KEY(u, t, s->units, i) + if (unit_id(u) == t) + unit_dump(u, f, prefix); } void manager_clear_jobs(Manager *m) { @@ -721,3 +1238,337 @@ void manager_clear_jobs(Manager *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)) { + Unit *u = (Unit*) meta; + assert(u->meta.in_dbus_queue); + + bus_unit_send_change_signal(u); + 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); + + 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); + } + + return 0; +} + +static int manager_process_signal_fd(Manager *m, bool *quit) { + 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 SIGINT: + case SIGTERM: + + if (m->running_as != MANAGER_INIT) { + *quit = true; + return 0; + + } else { + Unit *target; + int r; + + if ((r = manager_load_unit(m, SPECIAL_CTRL_ALT_DEL_TARGET, &target)) < 0) + log_error("Failed to load ctrl-alt-del target: %s", strerror(-r)); + else if ((r = manager_add_job(m, JOB_START, target, JOB_REPLACE, true, NULL)) < 0) + log_error("Failed to enqueue ctrl-alt-del job: %s", strerror(-r)); + + break; + } + + case SIGWINCH: + + if (m->running_as == MANAGER_INIT) { + Unit *target; + int r; + + if ((r = manager_load_unit(m, SPECIAL_KBREQUEST_TARGET, &target)) < 0) + log_error("Failed to load kbrequest target: %s", strerror(-r)); + else if ((r = manager_add_job(m, JOB_START, target, JOB_REPLACE, true, NULL)) < 0) + log_error("Failed to enqueue kbrequest job: %s", strerror(-r)); + + break; + } + + /* This is a nop on non-init systemd's */ + + 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, 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->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; + bool quit = false; + + RATELIMIT_DEFINE(rl, 1*USEC_PER_SEC, 1000); + + assert(m); + + for (;;) { + 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_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, &quit)) < 0) + return r; + + if (quit) + return 0; + } +} + +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 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);