From 93a0884126146361ca078ec627da2cf766205a1c Mon Sep 17 00:00:00 2001 From: Martin Pitt Date: Mon, 5 Sep 2016 13:14:36 +0200 Subject: [PATCH] systemctl: Add --wait option to wait until started units terminate again Fixes #3830 --- man/systemctl.xml | 15 ++- src/systemctl/systemctl.c | 168 ++++++++++++++++++++++++++++++++- test/TEST-03-JOBS/test-jobs.sh | 28 ++++++ 3 files changed, 207 insertions(+), 4 deletions(-) diff --git a/man/systemctl.xml b/man/systemctl.xml index 0bf9e1fd3f..e738b5aecd 100644 --- a/man/systemctl.xml +++ b/man/systemctl.xml @@ -363,7 +363,20 @@ to finish. If this is not specified, the job will be verified, enqueued and systemctl will wait until the unit's start-up is completed. By passing this - argument, it is only verified and enqueued. + argument, it is only verified and enqueued. This option may not be + combined with . + + + + + + + + Synchronously wait for started units to terminate again. + This option may not be combined with . + Note that this will wait forever if any given unit never terminates + (by itself or by getting stopped explicitly); particularly services + which use RemainAfterExit=yes. diff --git a/src/systemctl/systemctl.c b/src/systemctl/systemctl.c index 5337561664..bb6002e8ef 100644 --- a/src/systemctl/systemctl.c +++ b/src/systemctl/systemctl.c @@ -118,6 +118,7 @@ static enum dependency { } arg_dependency = DEPENDENCY_FORWARD; static const char *arg_job_mode = "replace"; static UnitFileScope arg_scope = UNIT_FILE_SYSTEM; +static bool arg_wait = false; static bool arg_no_block = false; static bool arg_no_legend = false; static bool arg_no_pager = false; @@ -2679,13 +2680,86 @@ static const char *method_to_verb(const char *method) { return "n/a"; } +typedef struct { + sd_bus_slot *match; + sd_event *event; + Set *unit_paths; + bool any_failed; +} WaitContext; + +static void wait_context_free(WaitContext *c) { + c->match = sd_bus_slot_unref(c->match); + c->event = sd_event_unref(c->event); + c->unit_paths = set_free(c->unit_paths); +} + +static int on_properties_changed(sd_bus_message *m, void *userdata, sd_bus_error *error) { + WaitContext *c = userdata; + const char *path; + int r; + + path = sd_bus_message_get_path(m); + if (!set_contains(c->unit_paths, path)) + return 0; + + /* Check if ActiveState changed to inactive/failed */ + /* (s interface, a{sv} changed_properties, as invalidated_properties) */ + r = sd_bus_message_skip(m, "s"); + if (r < 0) + return bus_log_parse_error(r); + r = sd_bus_message_enter_container(m, SD_BUS_TYPE_ARRAY, "{sv}"); + if (r < 0) + return bus_log_parse_error(r); + + while ((r = sd_bus_message_enter_container(m, SD_BUS_TYPE_DICT_ENTRY, "sv")) > 0) { + const char *s; + bool is_failed; + + r = sd_bus_message_read(m, "s", &s); + if (r < 0) + return bus_log_parse_error(r); + if (streq(s, "ActiveState")) { + r = sd_bus_message_enter_container(m, SD_BUS_TYPE_VARIANT, "s"); + if (r < 0) + return bus_log_parse_error(r); + r = sd_bus_message_read(m, "s", &s); + if (r < 0) + return bus_log_parse_error(r); + is_failed = streq(s, "failed"); + if (streq(s, "inactive") || is_failed) { + log_debug("%s became %s, dropping from --wait tracking", path, s); + set_remove(c->unit_paths, path); + c->any_failed |= is_failed; + } else + log_debug("ActiveState on %s changed to %s", path, s); + break; /* no need to dissect the rest of the message */ + } else { + /* other property */ + r = sd_bus_message_skip(m, "v"); + if (r < 0) + return bus_log_parse_error(r); + } + r = sd_bus_message_exit_container(m); + if (r < 0) + return bus_log_parse_error(r); + } + if (r < 0) + return bus_log_parse_error(r); + + if (set_isempty(c->unit_paths)) + sd_event_exit(c->event, EXIT_SUCCESS); + + return 0; +} + static int start_unit_one( sd_bus *bus, const char *method, const char *name, const char *mode, sd_bus_error *error, - BusWaitForJobs *w) { + BusWaitForJobs *w, + WaitContext *wait_context) { _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL; const char *path; @@ -2696,6 +2770,40 @@ static int start_unit_one( assert(mode); assert(error); + if (wait_context) { + _cleanup_free_ char *unit_path = NULL; + const char* mt; + + log_debug("Watching for property changes of %s", name); + r = sd_bus_call_method( + bus, + "org.freedesktop.systemd1", + "/org/freedesktop/systemd1", + "org.freedesktop.systemd1.Manager", + "RefUnit", + error, + NULL, + "s", name); + if (r < 0) + return log_error_errno(r, "Failed to RefUnit %s: %s", name, bus_error_message(error, r)); + + unit_path = unit_dbus_path_from_name(name); + if (!unit_path) + return log_oom(); + + r = set_put_strdup(wait_context->unit_paths, unit_path); + if (r < 0) + return log_error_errno(r, "Failed to add unit path %s to set: %m", unit_path); + + mt = strjoina("type='signal'," + "interface='org.freedesktop.DBus.Properties'," + "path='", unit_path, "'," + "member='PropertiesChanged'"); + r = sd_bus_add_match(bus, &wait_context->match, mt, on_properties_changed, wait_context); + if (r < 0) + return log_error_errno(r, "Failed to add match for PropertiesChanged signal: %m"); + } + log_debug("Calling manager for %s on %s, %s", method, name, mode); r = sd_bus_call_method( @@ -2841,10 +2949,18 @@ static int start_unit(int argc, char *argv[], void *userdata) { const char *method, *mode, *one_name, *suffix = NULL; _cleanup_strv_free_ char **names = NULL; sd_bus *bus; + _cleanup_(wait_context_free) WaitContext wait_context = {}; char **name; int r = 0; - r = acquire_bus(BUS_MANAGER, &bus); + if (arg_wait && !strstr(argv[0], "start")) { + log_error("--wait may only be used with a command that starts units."); + return -EINVAL; + } + + /* we cannot do sender tracking on the private bus, so we need the full + * one for RefUnit to implement --wait */ + r = acquire_bus(arg_wait ? BUS_FULL : BUS_MANAGER, &bus); if (r < 0) return r; @@ -2888,11 +3004,36 @@ static int start_unit(int argc, char *argv[], void *userdata) { return log_error_errno(r, "Could not watch jobs: %m"); } + if (arg_wait) { + _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL; + + wait_context.unit_paths = set_new(&string_hash_ops); + if (!wait_context.unit_paths) + return log_oom(); + + r = sd_bus_call_method( + bus, + "org.freedesktop.systemd1", + "/org/freedesktop/systemd1", + "org.freedesktop.systemd1.Manager", + "Subscribe", + &error, + NULL, NULL); + if (r < 0) + return log_error_errno(r, "Failed to enable subscription: %s", bus_error_message(&error, r)); + r = sd_event_default(&wait_context.event); + if (r < 0) + return log_error_errno(r, "Failed to allocate event loop: %m"); + r = sd_bus_attach_event(bus, wait_context.event, 0); + if (r < 0) + return log_error_errno(r, "Failed to attach bus to event loop: %m"); + } + STRV_FOREACH(name, names) { _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL; int q; - q = start_unit_one(bus, method, *name, mode, &error, w); + q = start_unit_one(bus, method, *name, mode, &error, w, arg_wait ? &wait_context : NULL); if (r >= 0 && q < 0) r = translate_bus_error_to_exit_status(q, &error); } @@ -2924,6 +3065,15 @@ static int start_unit(int argc, char *argv[], void *userdata) { check_triggering_units(bus, *name); } + if (r >= 0 && arg_wait) { + int q; + q = sd_event_loop(wait_context.event); + if (q < 0) + return log_error_errno(q, "Failed to run event loop: %m"); + if (wait_context.any_failed) + r = EXIT_FAILURE; + } + return r; } @@ -6587,6 +6737,7 @@ static void systemctl_help(void) { " -s --signal=SIGNAL Which signal to send\n" " --now Start or stop unit in addition to enabling or disabling it\n" " -q --quiet Suppress output\n" + " --wait For (re)start, wait until service stopped again\n" " --no-block Do not wait until operation finished\n" " --no-wall Don't send wall message before halt/power-off/reboot\n" " --no-reload Don't reload daemon after en-/dis-abling unit files\n" @@ -6857,6 +7008,7 @@ static int systemctl_parse_argv(int argc, char *argv[]) { ARG_FIRMWARE_SETUP, ARG_NOW, ARG_MESSAGE, + ARG_WAIT, }; static const struct option options[] = { @@ -6880,6 +7032,7 @@ static int systemctl_parse_argv(int argc, char *argv[]) { { "user", no_argument, NULL, ARG_USER }, { "system", no_argument, NULL, ARG_SYSTEM }, { "global", no_argument, NULL, ARG_GLOBAL }, + { "wait", no_argument, NULL, ARG_WAIT }, { "no-block", no_argument, NULL, ARG_NO_BLOCK }, { "no-legend", no_argument, NULL, ARG_NO_LEGEND }, { "no-pager", no_argument, NULL, ARG_NO_PAGER }, @@ -7060,6 +7213,10 @@ static int systemctl_parse_argv(int argc, char *argv[]) { arg_scope = UNIT_FILE_GLOBAL; break; + case ARG_WAIT: + arg_wait = true; + break; + case ARG_NO_BLOCK: arg_no_block = true; break; @@ -7235,6 +7392,11 @@ static int systemctl_parse_argv(int argc, char *argv[]) { return -EINVAL; } + if (arg_wait && arg_no_block) { + log_error("--wait may not be combined with --no-block."); + return -EINVAL; + } + return 1; } diff --git a/test/TEST-03-JOBS/test-jobs.sh b/test/TEST-03-JOBS/test-jobs.sh index 0c7d4439a2..fa6cf4181a 100755 --- a/test/TEST-03-JOBS/test-jobs.sh +++ b/test/TEST-03-JOBS/test-jobs.sh @@ -49,4 +49,32 @@ systemctl stop --job-mode=replace-irreversibly unstoppable.service || exit 1 # Shutdown of the container/VM will hang if not. systemctl start unstoppable.service || exit 1 +# Test waiting for a started unit(s) to terminate again +cat < /run/systemd/system/wait2.service +[Unit] +Description=Wait for 2 seconds +[Service] +ExecStart=/bin/sh -ec 'sleep 2' +EOF +cat < /run/systemd/system/wait5fail.service +[Unit] +Description=Wait for 5 seconds and fail +[Service] +ExecStart=/bin/sh -ec 'sleep 5; false' +EOF + +# wait2 succeeds +START_SEC=$(date -u '+%s') +systemctl start --wait wait2.service || exit 1 +END_SEC=$(date -u '+%s') +ELAPSED=$(($END_SEC-$START_SEC)) +[[ "$ELAPSED" -ge 2 ]] && [[ "$ELAPSED" -le 3 ]] || exit 1 + +# wait5fail fails, so systemctl should fail +START_SEC=$(date -u '+%s') +! systemctl start --wait wait2.service wait5fail.service || exit 1 +END_SEC=$(date -u '+%s') +ELAPSED=$(($END_SEC-$START_SEC)) +[[ "$ELAPSED" -ge 5 ]] && [[ "$ELAPSED" -le 7 ]] || exit 1 + touch /testok