diff options
Diffstat (limited to 'src/core/busname.c')
| -rw-r--r-- | src/core/busname.c | 600 |
1 files changed, 600 insertions, 0 deletions
diff --git a/src/core/busname.c b/src/core/busname.c new file mode 100644 index 0000000000..c45265658c --- /dev/null +++ b/src/core/busname.c @@ -0,0 +1,600 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +/*** + This file is part of systemd. + + Copyright 2013 Lennart Poettering + + systemd is free software; you can redistribute it and/or modify it + under the terms of the GNU Lesser General Public License as published by + the Free Software Foundation; either version 2.1 of the License, or + (at your option) any later version. + + systemd is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with systemd; If not, see <http://www.gnu.org/licenses/>. +***/ + +#include "special.h" +#include "bus-kernel.h" +#include "bus-internal.h" +#include "bus-util.h" +#include "service.h" +#include "dbus-busname.h" +#include "busname.h" + +static const UnitActiveState state_translation_table[_BUSNAME_STATE_MAX] = { + [BUSNAME_DEAD] = UNIT_INACTIVE, + [BUSNAME_LISTENING] = UNIT_ACTIVE, + [BUSNAME_RUNNING] = UNIT_ACTIVE, + [BUSNAME_FAILED] = UNIT_FAILED +}; + +static int busname_dispatch_io(sd_event_source *source, int fd, uint32_t revents, void *userdata); + +static void busname_init(Unit *u) { + BusName *n = BUSNAME(u); + + assert(u); + assert(u->load_state == UNIT_STUB); + + n->starter_fd = -1; +} + +static void busname_done(Unit *u) { + BusName *n = BUSNAME(u); + + assert(u); + + free(n->name); + n->name = NULL; + + unit_ref_unset(&n->service); + + n->event_source = sd_event_source_unref(n->event_source); + + if (n->starter_fd >= 0) { + close_nointr_nofail(n->starter_fd); + n->starter_fd = -1; + } +} + +static int busname_add_default_default_dependencies(BusName *n) { + int r; + + assert(n); + + r = unit_add_dependency_by_name(UNIT(n), UNIT_BEFORE, SPECIAL_BUSNAMES_TARGET, NULL, true); + if (r < 0) + return r; + + if (UNIT(n)->manager->running_as == SYSTEMD_SYSTEM) { + r = unit_add_two_dependencies_by_name(UNIT(n), UNIT_AFTER, UNIT_REQUIRES, SPECIAL_SYSINIT_TARGET, NULL, true); + if (r < 0) + return r; + } + + return unit_add_two_dependencies_by_name(UNIT(n), UNIT_BEFORE, UNIT_CONFLICTS, SPECIAL_SHUTDOWN_TARGET, NULL, true); +} + +static int busname_add_extras(BusName *n) { + Unit *u = UNIT(n); + int r; + + assert(n); + + if (!n->name) { + n->name = unit_name_to_prefix(u->id); + if (!n->name) + return -ENOMEM; + } + + if (!u->description) { + r = unit_set_description(u, n->name); + if (r < 0) + return r; + } + + if (!UNIT_DEREF(n->service)) { + Unit *x; + + r = unit_load_related_unit(u, ".service", &x); + if (r < 0) + return r; + + unit_ref_set(&n->service, x); + } + + r = unit_add_two_dependencies(u, UNIT_BEFORE, UNIT_TRIGGERS, UNIT_DEREF(n->service), true); + if (r < 0) + return r; + + if (u->default_dependencies) { + r = busname_add_default_default_dependencies(n); + if (r < 0) + return r; + } + + return 0; +} + + + +static int busname_verify(BusName *n) { + char *e; + + assert(n); + + if (UNIT(n)->load_state != UNIT_LOADED) + return 0; + + if (!service_name_is_valid(n->name)) { + log_error_unit(UNIT(n)->id, "%s's Name= setting is not a valid service name Refusing.", UNIT(n)->id); + return -EINVAL; + } + + e = strappenda(n->name, ".busname"); + if (!unit_has_name(UNIT(n), e)) { + log_error_unit(UNIT(n)->id, "%s's Name= setting doesn't match unit name. Refusing.", UNIT(n)->id); + return -EINVAL; + } + + return 0; +} + +static int busname_load(Unit *u) { + BusName *n = BUSNAME(u); + int r; + + assert(u); + assert(u->load_state == UNIT_STUB); + + r = unit_load_fragment_and_dropin(u); + if (r < 0) + return r; + + if (u->load_state == UNIT_LOADED) { + /* This is a new unit? Then let's add in some extras */ + r = busname_add_extras(n); + if (r < 0) + return r; + } + + return busname_verify(n); +} + +static void busname_dump(Unit *u, FILE *f, const char *prefix) { + BusName *n = BUSNAME(u); + + assert(n); + assert(f); + + fprintf(f, + "%sBus Name State: %s\n" + "%sResult: %s\n" + "%sName: %s\n", + prefix, busname_state_to_string(n->state), + prefix, busname_result_to_string(n->result), + prefix, n->name); +} + +static void busname_unwatch_fd(BusName *n) { + int r; + + assert(n); + + if (n->event_source) { + r = sd_event_source_set_enabled(n->event_source, SD_EVENT_OFF); + if (r < 0) + log_debug_unit(UNIT(n)->id, "Failed to disable event source."); + } +} + +static void busname_close_fd(BusName *n) { + assert(n); + + if (n->starter_fd <= 0) + return; + + close_nointr_nofail(n->starter_fd); + n->starter_fd = -1; +} + +static int busname_watch_fd(BusName *n) { + int r; + + assert(n); + + if (n->starter_fd < 0) + return 0; + + if (n->event_source) + r = sd_event_source_set_enabled(n->event_source, SD_EVENT_ON); + else + r = sd_event_add_io(UNIT(n)->manager->event, n->starter_fd, EPOLLIN, busname_dispatch_io, n, &n->event_source); + if (r < 0) { + log_warning_unit(UNIT(n)->id, "Failed to watch starter fd: %s", strerror(-r)); + busname_unwatch_fd(n); + return r; + } + + return 0; +} + +static int busname_open_fd(BusName *n) { + assert(n); + + if (n->starter_fd >= 0) + return 0; + + n->starter_fd = bus_kernel_create_starter(UNIT(n)->manager->running_as == SYSTEMD_SYSTEM ? "system" : "user", n->name); + if (n->starter_fd < 0) { + log_warning_unit(UNIT(n)->id, "Failed to create starter fd: %s", strerror(-n->starter_fd)); + return n->starter_fd; + } + + return 0; +} + +static void busname_set_state(BusName *n, BusNameState state) { + BusNameState old_state; + assert(n); + + old_state = n->state; + n->state = state; + + if (state != BUSNAME_LISTENING) + busname_unwatch_fd(n); + + if (!IN_SET(state, BUSNAME_LISTENING, BUSNAME_RUNNING)) + busname_close_fd(n); + + if (state != old_state) + log_debug_unit(UNIT(n)->id, "%s changed %s -> %s", + UNIT(n)->id, busname_state_to_string(old_state), busname_state_to_string(state)); + + unit_notify(UNIT(n), state_translation_table[old_state], state_translation_table[state], true); +} + +static int busname_coldplug(Unit *u) { + BusName *n = BUSNAME(u); + int r; + + assert(n); + assert(n->state == BUSNAME_DEAD); + + if (n->deserialized_state == n->state) + return 0; + + if (IN_SET(n->deserialized_state, BUSNAME_LISTENING, BUSNAME_RUNNING)) { + r = busname_open_fd(n); + if (r < 0) + return r; + } + + if (n->deserialized_state == BUSNAME_LISTENING) { + r = busname_watch_fd(n); + if (r < 0) + return r; + } + + busname_set_state(n, n->deserialized_state); + return 0; +} + +static void busname_enter_dead(BusName *n, BusNameResult f) { + assert(n); + + if (f != BUSNAME_SUCCESS) + n->result = f; + + busname_set_state(n, n->result != BUSNAME_SUCCESS ? BUSNAME_FAILED : BUSNAME_DEAD); +} + +static void busname_enter_listening(BusName *n) { + int r; + + assert(n); + + r = busname_open_fd(n); + if (r < 0) { + log_warning_unit(UNIT(n)->id, "%s failed to listen on bus names: %s", UNIT(n)->id, strerror(-r)); + goto fail; + } + + r = busname_watch_fd(n); + if (r < 0) { + log_warning_unit(UNIT(n)->id, "%s failed to watch names: %s", UNIT(n)->id, strerror(-r)); + goto fail; + } + + busname_set_state(n, BUSNAME_LISTENING); + return; + +fail: + busname_enter_dead(n, BUSNAME_FAILURE_RESOURCES); +} + +static void busname_enter_running(BusName *n) { + _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL; + bool pending = false; + Unit *other; + Iterator i; + int r; + + assert(n); + + /* We don't take conenctions anymore if we are supposed to + * shut down anyway */ + + if (unit_stop_pending(UNIT(n))) { + log_debug_unit(UNIT(n)->id, "Suppressing activation request on %s since unit stop is scheduled.", UNIT(n)->id); + return; + } + + /* If there's already a start pending don't bother to do + * anything */ + SET_FOREACH(other, UNIT(n)->dependencies[UNIT_TRIGGERS], i) + if (unit_active_or_pending(other)) { + pending = true; + break; + } + + if (!pending) { + r = manager_add_job(UNIT(n)->manager, JOB_START, UNIT_DEREF(n->service), JOB_REPLACE, true, &error, NULL); + if (r < 0) + goto fail; + } + + busname_set_state(n, BUSNAME_RUNNING); + return; + +fail: + log_warning_unit(UNIT(n)->id, "%s failed to queue service startup job: %s", UNIT(n)->id, bus_error_message(&error, r)); + busname_enter_dead(n, BUSNAME_FAILURE_RESOURCES); +} + +static int busname_start(Unit *u) { + BusName *n = BUSNAME(u); + + assert(n); + + if (UNIT_ISSET(n->service)) { + Service *service; + + service = SERVICE(UNIT_DEREF(n->service)); + + if (UNIT(service)->load_state != UNIT_LOADED) { + log_error_unit(u->id, "Bus service %s not loaded, refusing.", UNIT(service)->id); + return -ENOENT; + } + } + + assert(IN_SET(n->state, BUSNAME_DEAD, BUSNAME_FAILED)); + + n->result = BUSNAME_SUCCESS; + busname_enter_listening(n); + + return 0; +} + +static int busname_stop(Unit *u) { + BusName *n = BUSNAME(u); + + assert(n); + assert(n->state == BUSNAME_LISTENING || n->state == BUSNAME_RUNNING); + + busname_enter_dead(n, BUSNAME_SUCCESS); + return 0; +} + +static int busname_serialize(Unit *u, FILE *f, FDSet *fds) { + BusName *n = BUSNAME(u); + + assert(n); + assert(f); + assert(fds); + + unit_serialize_item(u, f, "state", busname_state_to_string(n->state)); + unit_serialize_item(u, f, "result", busname_result_to_string(n->result)); + + if (n->starter_fd >= 0) { + int copy; + + copy = fdset_put_dup(fds, n->starter_fd); + if (copy < 0) + return copy; + + unit_serialize_item_format(u, f, "starter-fd", "%i", copy); + } + + return 0; +} + +static int busname_deserialize_item(Unit *u, const char *key, const char *value, FDSet *fds) { + BusName *n = BUSNAME(u); + + assert(n); + assert(key); + assert(value); + + if (streq(key, "state")) { + BusNameState state; + + state = busname_state_from_string(value); + if (state < 0) + log_debug_unit(u->id, "Failed to parse state value %s", value); + else + n->deserialized_state = state; + + } else if (streq(key, "result")) { + BusNameResult f; + + f = busname_result_from_string(value); + if (f < 0) + log_debug_unit(u->id, "Failed to parse result value %s", value); + else if (f != BUSNAME_SUCCESS) + n->result = f; + + } else if (streq(key, "starter-fd")) { + int fd; + + if (safe_atoi(value, &fd) < 0 || fd < 0 || !fdset_contains(fds, fd)) + log_debug_unit(u->id, "Failed to parse starter fd value %s", value); + else { + if (n->starter_fd >= 0) + close_nointr_nofail(n->starter_fd); + n->starter_fd = fdset_remove(fds, fd); + } + } else + log_debug_unit(u->id, "Unknown serialization key '%s'", key); + + return 0; +} + +_pure_ static UnitActiveState busname_active_state(Unit *u) { + assert(u); + + return state_translation_table[BUSNAME(u)->state]; +} + +_pure_ static const char *busname_sub_state_to_string(Unit *u) { + assert(u); + + return busname_state_to_string(BUSNAME(u)->state); +} + +static int busname_dispatch_io(sd_event_source *source, int fd, uint32_t revents, void *userdata) { + BusName *n = userdata; + + assert(n); + assert(fd >= 0); + + if (n->state != BUSNAME_LISTENING) + return 0; + + log_debug_unit(UNIT(n)->id, "Activation request on %s", UNIT(n)->id); + + if (revents != EPOLLIN) { + log_error_unit(UNIT(n)->id, "%s: Got unexpected poll event (0x%x) on starter fd.", + UNIT(n)->id, revents); + goto fail; + } + + busname_enter_running(n); + return 0; +fail: + + busname_enter_dead(n, BUSNAME_FAILURE_RESOURCES); + return 0; +} + +static void busname_reset_failed(Unit *u) { + BusName *n = BUSNAME(u); + + assert(n); + + if (n->state == BUSNAME_FAILED) + busname_set_state(n, BUSNAME_DEAD); + + n->result = BUSNAME_SUCCESS; +} + +static void busname_trigger_notify(Unit *u, Unit *other) { + BusName *n = BUSNAME(u); + Service *s; + + assert(n); + assert(other); + + if (!IN_SET(n->state, BUSNAME_RUNNING, BUSNAME_LISTENING)) + return; + + if (other->load_state != UNIT_LOADED || other->type != UNIT_SERVICE) + return; + + s = SERVICE(other); + + if (s->state == SERVICE_FAILED) { + if (s->result == SERVICE_FAILURE_START_LIMIT) + busname_enter_dead(n, BUSNAME_FAILURE_SERVICE_FAILED_PERMANENT); + else + busname_enter_listening(n); + } + + if (IN_SET(n->state, + SERVICE_DEAD, + SERVICE_STOP, SERVICE_STOP_SIGTERM, SERVICE_STOP_SIGKILL, + SERVICE_STOP_POST, SERVICE_FINAL_SIGTERM, SERVICE_FINAL_SIGKILL, + SERVICE_AUTO_RESTART)) + busname_enter_listening(n); +} + +static const char* const busname_state_table[_BUSNAME_STATE_MAX] = { + [BUSNAME_DEAD] = "dead", + [BUSNAME_LISTENING] = "listening", + [BUSNAME_RUNNING] = "running", + [BUSNAME_FAILED] = "failed" +}; + +DEFINE_STRING_TABLE_LOOKUP(busname_state, BusNameState); + +static const char* const busname_result_table[_BUSNAME_RESULT_MAX] = { + [BUSNAME_SUCCESS] = "success", + [BUSNAME_FAILURE_RESOURCES] = "resources", +}; + +DEFINE_STRING_TABLE_LOOKUP(busname_result, BusNameResult); + +const UnitVTable busname_vtable = { + .object_size = sizeof(BusName), + + .sections = + "Unit\0" + "BusName\0" + "Install\0", + .private_section = "BusName", + + .init = busname_init, + .done = busname_done, + .load = busname_load, + + .coldplug = busname_coldplug, + + .dump = busname_dump, + + .start = busname_start, + .stop = busname_stop, + + .serialize = busname_serialize, + .deserialize_item = busname_deserialize_item, + + .active_state = busname_active_state, + .sub_state_to_string = busname_sub_state_to_string, + + .trigger_notify = busname_trigger_notify, + + .reset_failed = busname_reset_failed, + + .bus_interface = "org.freedesktop.systemd1.BusName", + .bus_vtable = bus_busname_vtable, + .bus_changing_properties = bus_busname_changing_properties, + + .status_message_formats = { + .finished_start_job = { + [JOB_DONE] = "Listening on %s.", + [JOB_FAILED] = "Failed to listen on %s.", + [JOB_DEPENDENCY] = "Dependency failed for %s.", + [JOB_TIMEOUT] = "Timed out starting %s.", + }, + .finished_stop_job = { + [JOB_DONE] = "Closed %s.", + [JOB_FAILED] = "Failed stopping %s.", + [JOB_TIMEOUT] = "Timed out stopping %s.", + }, + }, +}; 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