summaryrefslogtreecommitdiff
path: root/src/libcore/busname.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/libcore/busname.c')
-rw-r--r--src/libcore/busname.c1067
1 files changed, 1067 insertions, 0 deletions
diff --git a/src/libcore/busname.c b/src/libcore/busname.c
new file mode 100644
index 0000000000..de2a21ccde
--- /dev/null
+++ b/src/libcore/busname.c
@@ -0,0 +1,1067 @@
+/***
+ 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 <sys/mman.h>
+
+#include "alloc-util.h"
+#include "bus-internal.h"
+#include "bus-kernel.h"
+#include "bus-policy.h"
+#include "bus-util.h"
+#include "busname.h"
+#include "dbus-busname.h"
+#include "fd-util.h"
+#include "formats-util.h"
+#include "kdbus.h"
+#include "parse-util.h"
+#include "process-util.h"
+#include "service.h"
+#include "signal-util.h"
+#include "special.h"
+#include "string-table.h"
+#include "string-util.h"
+
+static const UnitActiveState state_translation_table[_BUSNAME_STATE_MAX] = {
+ [BUSNAME_DEAD] = UNIT_INACTIVE,
+ [BUSNAME_MAKING] = UNIT_ACTIVATING,
+ [BUSNAME_REGISTERED] = UNIT_ACTIVE,
+ [BUSNAME_LISTENING] = UNIT_ACTIVE,
+ [BUSNAME_RUNNING] = UNIT_ACTIVE,
+ [BUSNAME_SIGTERM] = UNIT_DEACTIVATING,
+ [BUSNAME_SIGKILL] = UNIT_DEACTIVATING,
+ [BUSNAME_FAILED] = UNIT_FAILED
+};
+
+static int busname_dispatch_io(sd_event_source *source, int fd, uint32_t revents, void *userdata);
+static int busname_dispatch_timer(sd_event_source *source, usec_t usec, void *userdata);
+
+static void busname_init(Unit *u) {
+ BusName *n = BUSNAME(u);
+
+ assert(u);
+ assert(u->load_state == UNIT_STUB);
+
+ n->starter_fd = -1;
+ n->accept_fd = true;
+ n->activating = true;
+
+ n->timeout_usec = u->manager->default_timeout_start_usec;
+}
+
+static void busname_unwatch_control_pid(BusName *n) {
+ assert(n);
+
+ if (n->control_pid <= 0)
+ return;
+
+ unit_unwatch_pid(UNIT(n), n->control_pid);
+ n->control_pid = 0;
+}
+
+static void busname_free_policy(BusName *n) {
+ BusNamePolicy *p;
+
+ assert(n);
+
+ while ((p = n->policy)) {
+ LIST_REMOVE(policy, n->policy, p);
+
+ free(p->name);
+ free(p);
+ }
+}
+
+static void busname_close_fd(BusName *n) {
+ assert(n);
+
+ n->starter_event_source = sd_event_source_unref(n->starter_event_source);
+ n->starter_fd = safe_close(n->starter_fd);
+}
+
+static void busname_done(Unit *u) {
+ BusName *n = BUSNAME(u);
+
+ assert(n);
+
+ n->name = mfree(n->name);
+
+ busname_free_policy(n);
+ busname_unwatch_control_pid(n);
+ busname_close_fd(n);
+
+ unit_ref_unset(&n->service);
+
+ n->timer_event_source = sd_event_source_unref(n->timer_event_source);
+}
+
+static int busname_arm_timer(BusName *n, usec_t usec) {
+ int r;
+
+ assert(n);
+
+ if (n->timer_event_source) {
+ r = sd_event_source_set_time(n->timer_event_source, usec);
+ if (r < 0)
+ return r;
+
+ return sd_event_source_set_enabled(n->timer_event_source, SD_EVENT_ONESHOT);
+ }
+
+ if (usec == USEC_INFINITY)
+ return 0;
+
+ r = sd_event_add_time(
+ UNIT(n)->manager->event,
+ &n->timer_event_source,
+ CLOCK_MONOTONIC,
+ usec, 0,
+ busname_dispatch_timer, n);
+ if (r < 0)
+ return r;
+
+ (void) sd_event_source_set_description(n->timer_event_source, "busname-timer");
+
+ return 0;
+}
+
+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 == MANAGER_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) {
+ r = unit_name_to_prefix(u->id, &n->name);
+ if (r < 0)
+ return r;
+ }
+
+ if (!u->description) {
+ r = unit_set_description(u, n->name);
+ if (r < 0)
+ return r;
+ }
+
+ if (n->activating) {
+ 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_unit_error(UNIT(n), "Name= setting is not a valid service name Refusing.");
+ return -EINVAL;
+ }
+
+ e = strjoina(n->name, ".busname");
+ if (!unit_has_name(UNIT(n), e)) {
+ log_unit_error(UNIT(n), "Name= setting doesn't match unit name. Refusing.");
+ 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"
+ "%sActivating: %s\n"
+ "%sAccept FD: %s\n",
+ prefix, busname_state_to_string(n->state),
+ prefix, busname_result_to_string(n->result),
+ prefix, n->name,
+ prefix, yes_no(n->activating),
+ prefix, yes_no(n->accept_fd));
+
+ if (n->control_pid > 0)
+ fprintf(f,
+ "%sControl PID: "PID_FMT"\n",
+ prefix, n->control_pid);
+}
+
+static void busname_unwatch_fd(BusName *n) {
+ int r;
+
+ assert(n);
+
+ if (!n->starter_event_source)
+ return;
+
+ r = sd_event_source_set_enabled(n->starter_event_source, SD_EVENT_OFF);
+ if (r < 0)
+ log_unit_debug_errno(UNIT(n), r, "Failed to disable event source: %m");
+}
+
+static int busname_watch_fd(BusName *n) {
+ int r;
+
+ assert(n);
+
+ if (n->starter_fd < 0)
+ return 0;
+
+ if (n->starter_event_source) {
+ r = sd_event_source_set_enabled(n->starter_event_source, SD_EVENT_ON);
+ if (r < 0)
+ goto fail;
+ } else {
+ r = sd_event_add_io(UNIT(n)->manager->event, &n->starter_event_source, n->starter_fd, EPOLLIN, busname_dispatch_io, n);
+ if (r < 0)
+ goto fail;
+
+ (void) sd_event_source_set_description(n->starter_event_source, "busname-starter");
+ }
+
+ return 0;
+
+fail:
+ log_unit_warning_errno(UNIT(n), r, "Failed to watch starter fd: %m");
+ busname_unwatch_fd(n);
+ return r;
+}
+
+static int busname_open_fd(BusName *n) {
+ _cleanup_free_ char *path = NULL;
+ const char *mode;
+
+ assert(n);
+
+ if (n->starter_fd >= 0)
+ return 0;
+
+ mode = UNIT(n)->manager->running_as == MANAGER_SYSTEM ? "system" : "user";
+ n->starter_fd = bus_kernel_open_bus_fd(mode, &path);
+ if (n->starter_fd < 0)
+ return log_unit_warning_errno(UNIT(n), n->starter_fd, "Failed to open %s: %m", path ?: "kdbus");
+
+ return 0;
+}
+
+static void busname_set_state(BusName *n, BusNameState state) {
+ BusNameState old_state;
+ assert(n);
+
+ old_state = n->state;
+ n->state = state;
+
+ if (!IN_SET(state, BUSNAME_MAKING, BUSNAME_SIGTERM, BUSNAME_SIGKILL)) {
+ n->timer_event_source = sd_event_source_unref(n->timer_event_source);
+ busname_unwatch_control_pid(n);
+ }
+
+ if (state != BUSNAME_LISTENING)
+ busname_unwatch_fd(n);
+
+ if (!IN_SET(state, BUSNAME_LISTENING, BUSNAME_MAKING, BUSNAME_REGISTERED, BUSNAME_RUNNING))
+ busname_close_fd(n);
+
+ if (state != old_state)
+ log_unit_debug(UNIT(n), "Changed %s -> %s", 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 (n->control_pid > 0 &&
+ pid_is_unwaited(n->control_pid) &&
+ IN_SET(n->deserialized_state, BUSNAME_MAKING, BUSNAME_SIGTERM, BUSNAME_SIGKILL)) {
+
+ r = unit_watch_pid(UNIT(n), n->control_pid);
+ if (r < 0)
+ return r;
+
+ r = busname_arm_timer(n, usec_add(u->state_change_timestamp.monotonic, n->timeout_usec));
+ if (r < 0)
+ return r;
+ }
+
+ if (IN_SET(n->deserialized_state, BUSNAME_MAKING, BUSNAME_LISTENING, BUSNAME_REGISTERED, 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 int busname_make_starter(BusName *n, pid_t *_pid) {
+ pid_t pid;
+ int r;
+
+ r = busname_arm_timer(n, usec_add(now(CLOCK_MONOTONIC), n->timeout_usec));
+ if (r < 0)
+ goto fail;
+
+ /* We have to resolve the user/group names out-of-process,
+ * hence let's fork here. It's messy, but well, what can we
+ * do? */
+
+ pid = fork();
+ if (pid < 0)
+ return -errno;
+
+ if (pid == 0) {
+ int ret;
+
+ (void) default_signals(SIGNALS_CRASH_HANDLER, SIGNALS_IGNORE, -1);
+ (void) ignore_signals(SIGPIPE, -1);
+ log_forget_fds();
+
+ r = bus_kernel_make_starter(n->starter_fd, n->name, n->activating, n->accept_fd, n->policy, n->policy_world);
+ if (r < 0) {
+ ret = EXIT_MAKE_STARTER;
+ goto fail_child;
+ }
+
+ _exit(0);
+
+ fail_child:
+ log_open();
+ log_error_errno(r, "Failed to create starter connection at step %s: %m", exit_status_to_string(ret, EXIT_STATUS_SYSTEMD));
+
+ _exit(ret);
+ }
+
+ r = unit_watch_pid(UNIT(n), pid);
+ if (r < 0)
+ goto fail;
+
+ *_pid = pid;
+ return 0;
+
+fail:
+ n->timer_event_source = sd_event_source_unref(n->timer_event_source);
+ return r;
+}
+
+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_signal(BusName *n, BusNameState state, BusNameResult f) {
+ KillContext kill_context = {};
+ int r;
+
+ assert(n);
+
+ if (f != BUSNAME_SUCCESS)
+ n->result = f;
+
+ kill_context_init(&kill_context);
+
+ r = unit_kill_context(UNIT(n),
+ &kill_context,
+ state != BUSNAME_SIGTERM ? KILL_KILL : KILL_TERMINATE,
+ -1,
+ n->control_pid,
+ false);
+ if (r < 0) {
+ log_unit_warning_errno(UNIT(n), r, "Failed to kill control process: %m");
+ goto fail;
+ }
+
+ if (r > 0) {
+ r = busname_arm_timer(n, usec_add(now(CLOCK_MONOTONIC), n->timeout_usec));
+ if (r < 0) {
+ log_unit_warning_errno(UNIT(n), r, "Failed to arm timer: %m");
+ goto fail;
+ }
+
+ busname_set_state(n, state);
+ } else if (state == BUSNAME_SIGTERM)
+ busname_enter_signal(n, BUSNAME_SIGKILL, BUSNAME_SUCCESS);
+ else
+ busname_enter_dead(n, BUSNAME_SUCCESS);
+
+ return;
+
+fail:
+ busname_enter_dead(n, BUSNAME_FAILURE_RESOURCES);
+}
+
+static void busname_enter_listening(BusName *n) {
+ int r;
+
+ assert(n);
+
+ if (n->activating) {
+ r = busname_watch_fd(n);
+ if (r < 0) {
+ log_unit_warning_errno(UNIT(n), r, "Failed to watch names: %m");
+ goto fail;
+ }
+
+ busname_set_state(n, BUSNAME_LISTENING);
+ } else
+ busname_set_state(n, BUSNAME_REGISTERED);
+
+ return;
+
+fail:
+ busname_enter_signal(n, BUSNAME_SIGTERM, BUSNAME_FAILURE_RESOURCES);
+}
+
+static void busname_enter_making(BusName *n) {
+ int r;
+
+ assert(n);
+
+ r = busname_open_fd(n);
+ if (r < 0)
+ goto fail;
+
+ if (n->policy) {
+ /* If there is a policy, we need to resolve user/group
+ * names, which we can't do from PID1, hence let's
+ * fork. */
+ busname_unwatch_control_pid(n);
+
+ r = busname_make_starter(n, &n->control_pid);
+ if (r < 0) {
+ log_unit_warning_errno(UNIT(n), r, "Failed to fork 'making' task: %m");
+ goto fail;
+ }
+
+ busname_set_state(n, BUSNAME_MAKING);
+ } else {
+ /* If there is no policy, we can do everything
+ * directly from PID 1, hence do so. */
+
+ r = bus_kernel_make_starter(n->starter_fd, n->name, n->activating, n->accept_fd, NULL, n->policy_world);
+ if (r < 0) {
+ log_unit_warning_errno(UNIT(n), r, "Failed to make starter: %m");
+ goto fail;
+ }
+
+ busname_enter_listening(n);
+ }
+
+ return;
+
+fail:
+ busname_enter_dead(n, BUSNAME_FAILURE_RESOURCES);
+}
+
+static void busname_enter_running(BusName *n) {
+ _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
+ bool pending = false;
+ Unit *other;
+ Iterator i;
+ int r;
+
+ assert(n);
+
+ if (!n->activating)
+ return;
+
+ /* We don't take connections anymore if we are supposed to
+ * shut down anyway */
+
+ if (unit_stop_pending(UNIT(n))) {
+ log_unit_debug(UNIT(n), "Suppressing activation request since unit stop is scheduled.");
+
+ /* Flush all queued activation reqeuest by closing and reopening the connection */
+ bus_kernel_drop_one(n->starter_fd);
+
+ busname_enter_listening(n);
+ 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) {
+ if (!UNIT_ISSET(n->service)) {
+ log_unit_error(UNIT(n), "Service to activate vanished, refusing activation.");
+ r = -ENOENT;
+ goto fail;
+ }
+
+ r = manager_add_job(UNIT(n)->manager, JOB_START, UNIT_DEREF(n->service), JOB_REPLACE, &error, NULL);
+ if (r < 0)
+ goto fail;
+ }
+
+ busname_set_state(n, BUSNAME_RUNNING);
+ return;
+
+fail:
+ log_unit_warning(UNIT(n), "Failed to queue service startup job: %s", bus_error_message(&error, r));
+ busname_enter_dead(n, BUSNAME_FAILURE_RESOURCES);
+}
+
+static int busname_start(Unit *u) {
+ BusName *n = BUSNAME(u);
+
+ assert(n);
+
+ /* We cannot fulfill this request right now, try again later
+ * please! */
+ if (IN_SET(n->state, BUSNAME_SIGTERM, BUSNAME_SIGKILL))
+ return -EAGAIN;
+
+ /* Already on it! */
+ if (n->state == BUSNAME_MAKING)
+ return 0;
+
+ if (n->activating && UNIT_ISSET(n->service)) {
+ Service *service;
+
+ service = SERVICE(UNIT_DEREF(n->service));
+
+ if (UNIT(service)->load_state != UNIT_LOADED) {
+ log_unit_error(u, "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_making(n);
+
+ return 1;
+}
+
+static int busname_stop(Unit *u) {
+ BusName *n = BUSNAME(u);
+
+ assert(n);
+
+ /* Already on it */
+ if (IN_SET(n->state, BUSNAME_SIGTERM, BUSNAME_SIGKILL))
+ return 0;
+
+ /* If there's already something running, we go directly into
+ * kill mode. */
+
+ if (n->state == BUSNAME_MAKING) {
+ busname_enter_signal(n, BUSNAME_SIGTERM, BUSNAME_SUCCESS);
+ return -EAGAIN;
+ }
+
+ assert(IN_SET(n->state, BUSNAME_REGISTERED, BUSNAME_LISTENING, BUSNAME_RUNNING));
+
+ busname_enter_dead(n, BUSNAME_SUCCESS);
+ return 1;
+}
+
+static int busname_serialize(Unit *u, FILE *f, FDSet *fds) {
+ BusName *n = BUSNAME(u);
+ int r;
+
+ 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->control_pid > 0)
+ unit_serialize_item_format(u, f, "control-pid", PID_FMT, n->control_pid);
+
+ r = unit_serialize_item_fd(u, f, fds, "starter-fd", n->starter_fd);
+ if (r < 0)
+ return r;
+
+ 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_unit_debug(u, "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_unit_debug(u, "Failed to parse result value: %s", value);
+ else if (f != BUSNAME_SUCCESS)
+ n->result = f;
+
+ } else if (streq(key, "control-pid")) {
+ pid_t pid;
+
+ if (parse_pid(value, &pid) < 0)
+ log_unit_debug(u, "Failed to parse control-pid value: %s", value);
+ else
+ n->control_pid = pid;
+ } else if (streq(key, "starter-fd")) {
+ int fd;
+
+ if (safe_atoi(value, &fd) < 0 || fd < 0 || !fdset_contains(fds, fd))
+ log_unit_debug(u, "Failed to parse starter fd value: %s", value);
+ else {
+ safe_close(n->starter_fd);
+ n->starter_fd = fdset_remove(fds, fd);
+ }
+ } else
+ log_unit_debug(u, "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_peek_message(BusName *n) {
+ struct kdbus_cmd_recv cmd_recv = {
+ .size = sizeof(cmd_recv),
+ .flags = KDBUS_RECV_PEEK,
+ };
+ struct kdbus_cmd_free cmd_free = {
+ .size = sizeof(cmd_free),
+ };
+ const char *comm = NULL;
+ struct kdbus_item *d;
+ struct kdbus_msg *k;
+ size_t start, ps, sz, delta;
+ void *p = NULL;
+ pid_t pid = 0;
+ int r;
+
+ /* Generate a friendly debug log message about which process
+ * caused triggering of this bus name. This simply peeks the
+ * metadata of the first queued message and logs it. */
+
+ assert(n);
+
+ /* Let's shortcut things a bit, if debug logging is turned off
+ * anyway. */
+
+ if (log_get_max_level() < LOG_DEBUG)
+ return 0;
+
+ r = ioctl(n->starter_fd, KDBUS_CMD_RECV, &cmd_recv);
+ if (r < 0) {
+ if (errno == EINTR || errno == EAGAIN)
+ return 0;
+
+ return log_unit_error_errno(UNIT(n), errno, "Failed to query activation message: %m");
+ }
+
+ /* We map as late as possible, and unmap imemdiately after
+ * use. On 32bit address space is scarce and we want to be
+ * able to handle a lot of activator connections at the same
+ * time, and hence shouldn't keep the mmap()s around for
+ * longer than necessary. */
+
+ ps = page_size();
+ start = (cmd_recv.msg.offset / ps) * ps;
+ delta = cmd_recv.msg.offset - start;
+ sz = PAGE_ALIGN(delta + cmd_recv.msg.msg_size);
+
+ p = mmap(NULL, sz, PROT_READ, MAP_SHARED, n->starter_fd, start);
+ if (p == MAP_FAILED) {
+ r = log_unit_error_errno(UNIT(n), errno, "Failed to map activation message: %m");
+ goto finish;
+ }
+
+ k = (struct kdbus_msg *) ((uint8_t *) p + delta);
+ KDBUS_ITEM_FOREACH(d, k, items) {
+ switch (d->type) {
+
+ case KDBUS_ITEM_PIDS:
+ pid = d->pids.pid;
+ break;
+
+ case KDBUS_ITEM_PID_COMM:
+ comm = d->str;
+ break;
+ }
+ }
+
+ if (pid > 0)
+ log_unit_debug(UNIT(n), "Activation triggered by process " PID_FMT " (%s)", pid, strna(comm));
+
+ r = 0;
+
+finish:
+ if (p)
+ (void) munmap(p, sz);
+
+ cmd_free.offset = cmd_recv.msg.offset;
+ if (ioctl(n->starter_fd, KDBUS_CMD_FREE, &cmd_free) < 0)
+ log_unit_warning(UNIT(n), "Failed to free peeked message, ignoring: %m");
+
+ return r;
+}
+
+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_unit_debug(UNIT(n), "Activation request");
+
+ if (revents != EPOLLIN) {
+ log_unit_error(UNIT(n), "Got unexpected poll event (0x%x) on starter fd.", revents);
+ goto fail;
+ }
+
+ busname_peek_message(n);
+ busname_enter_running(n);
+ return 0;
+fail:
+
+ busname_enter_dead(n, BUSNAME_FAILURE_RESOURCES);
+ return 0;
+}
+
+static void busname_sigchld_event(Unit *u, pid_t pid, int code, int status) {
+ BusName *n = BUSNAME(u);
+ BusNameResult f;
+
+ assert(n);
+ assert(pid >= 0);
+
+ if (pid != n->control_pid)
+ return;
+
+ n->control_pid = 0;
+
+ if (is_clean_exit(code, status, NULL))
+ f = BUSNAME_SUCCESS;
+ else if (code == CLD_EXITED)
+ f = BUSNAME_FAILURE_EXIT_CODE;
+ else if (code == CLD_KILLED)
+ f = BUSNAME_FAILURE_SIGNAL;
+ else if (code == CLD_DUMPED)
+ f = BUSNAME_FAILURE_CORE_DUMP;
+ else
+ assert_not_reached("Unknown sigchld code");
+
+ log_unit_full(u, f == BUSNAME_SUCCESS ? LOG_DEBUG : LOG_NOTICE, 0,
+ "Control process exited, code=%s status=%i", sigchld_code_to_string(code), status);
+
+ if (f != BUSNAME_SUCCESS)
+ n->result = f;
+
+ switch (n->state) {
+
+ case BUSNAME_MAKING:
+ if (f == BUSNAME_SUCCESS)
+ busname_enter_listening(n);
+ else
+ busname_enter_signal(n, BUSNAME_SIGTERM, f);
+ break;
+
+ case BUSNAME_SIGTERM:
+ case BUSNAME_SIGKILL:
+ busname_enter_dead(n, f);
+ break;
+
+ default:
+ assert_not_reached("Uh, control process died at wrong time.");
+ }
+
+ /* Notify clients about changed exit status */
+ unit_add_to_dbus_queue(u);
+}
+
+static int busname_dispatch_timer(sd_event_source *source, usec_t usec, void *userdata) {
+ BusName *n = BUSNAME(userdata);
+
+ assert(n);
+ assert(n->timer_event_source == source);
+
+ switch (n->state) {
+
+ case BUSNAME_MAKING:
+ log_unit_warning(UNIT(n), "Making timed out. Terminating.");
+ busname_enter_signal(n, BUSNAME_SIGTERM, BUSNAME_FAILURE_TIMEOUT);
+ break;
+
+ case BUSNAME_SIGTERM:
+ log_unit_warning(UNIT(n), "Stopping timed out. Killing.");
+ busname_enter_signal(n, BUSNAME_SIGKILL, BUSNAME_FAILURE_TIMEOUT);
+ break;
+
+ case BUSNAME_SIGKILL:
+ log_unit_warning(UNIT(n), "Processes still around after SIGKILL. Ignoring.");
+ busname_enter_dead(n, BUSNAME_FAILURE_TIMEOUT);
+ break;
+
+ default:
+ assert_not_reached("Timeout at wrong time.");
+ }
+
+ 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);
+
+ assert(n);
+ assert(other);
+
+ if (!IN_SET(n->state, BUSNAME_RUNNING, BUSNAME_LISTENING))
+ return;
+
+ if (other->start_limit_hit) {
+ busname_enter_dead(n, BUSNAME_FAILURE_SERVICE_START_LIMIT_HIT);
+ return;
+ }
+
+ if (other->load_state != UNIT_LOADED || other->type != UNIT_SERVICE)
+ return;
+
+ if (IN_SET(SERVICE(other)->state,
+ SERVICE_DEAD, SERVICE_FAILED,
+ SERVICE_FINAL_SIGTERM, SERVICE_FINAL_SIGKILL,
+ SERVICE_AUTO_RESTART))
+ busname_enter_listening(n);
+
+ if (SERVICE(other)->state == SERVICE_RUNNING)
+ busname_set_state(n, BUSNAME_RUNNING);
+}
+
+static int busname_kill(Unit *u, KillWho who, int signo, sd_bus_error *error) {
+ return unit_kill_common(u, who, signo, -1, BUSNAME(u)->control_pid, error);
+}
+
+static int busname_get_timeout(Unit *u, usec_t *timeout) {
+ BusName *n = BUSNAME(u);
+ usec_t t;
+ int r;
+
+ if (!n->timer_event_source)
+ return 0;
+
+ r = sd_event_source_get_time(n->timer_event_source, &t);
+ if (r < 0)
+ return r;
+ if (t == USEC_INFINITY)
+ return 0;
+
+ *timeout = t;
+ return 1;
+}
+
+static bool busname_supported(void) {
+ static int supported = -1;
+
+ if (supported < 0)
+ supported = is_kdbus_available();
+
+ return supported;
+}
+
+static const char* const busname_result_table[_BUSNAME_RESULT_MAX] = {
+ [BUSNAME_SUCCESS] = "success",
+ [BUSNAME_FAILURE_RESOURCES] = "resources",
+ [BUSNAME_FAILURE_TIMEOUT] = "timeout",
+ [BUSNAME_FAILURE_EXIT_CODE] = "exit-code",
+ [BUSNAME_FAILURE_SIGNAL] = "signal",
+ [BUSNAME_FAILURE_CORE_DUMP] = "core-dump",
+ [BUSNAME_FAILURE_SERVICE_START_LIMIT_HIT] = "service-start-limit-hit",
+};
+
+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",
+
+ .no_alias = true,
+ .no_instances = true,
+
+ .init = busname_init,
+ .done = busname_done,
+ .load = busname_load,
+
+ .coldplug = busname_coldplug,
+
+ .dump = busname_dump,
+
+ .start = busname_start,
+ .stop = busname_stop,
+
+ .kill = busname_kill,
+
+ .get_timeout = busname_get_timeout,
+
+ .serialize = busname_serialize,
+ .deserialize_item = busname_deserialize_item,
+
+ .active_state = busname_active_state,
+ .sub_state_to_string = busname_sub_state_to_string,
+
+ .sigchld_event = busname_sigchld_event,
+
+ .trigger_notify = busname_trigger_notify,
+
+ .reset_failed = busname_reset_failed,
+
+ .supported = busname_supported,
+
+ .bus_vtable = bus_busname_vtable,
+
+ .status_message_formats = {
+ .finished_start_job = {
+ [JOB_DONE] = "Listening on %s.",
+ [JOB_FAILED] = "Failed to listen on %s.",
+ },
+ .finished_stop_job = {
+ [JOB_DONE] = "Closed %s.",
+ [JOB_FAILED] = "Failed stopping %s.",
+ },
+ },
+};