diff options
Diffstat (limited to 'src/shared/bus-wait-for-jobs.c')
-rw-r--r-- | src/shared/bus-wait-for-jobs.c | 333 |
1 files changed, 333 insertions, 0 deletions
diff --git a/src/shared/bus-wait-for-jobs.c b/src/shared/bus-wait-for-jobs.c new file mode 100644 index 0000000..969c629 --- /dev/null +++ b/src/shared/bus-wait-for-jobs.c @@ -0,0 +1,333 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ + +#include "alloc-util.h" +#include "bus-wait-for-jobs.h" +#include "set.h" +#include "bus-util.h" +#include "bus-internal.h" +#include "unit-def.h" +#include "escape.h" +#include "strv.h" + +typedef struct BusWaitForJobs { + sd_bus *bus; + + /* The set of jobs to wait for, as bus object paths */ + Set *jobs; + + /* The unit name and job result of the last Job message */ + char *name; + char *result; + + sd_bus_slot *slot_job_removed; + sd_bus_slot *slot_disconnected; +} BusWaitForJobs; + +static int match_disconnected(sd_bus_message *m, void *userdata, sd_bus_error *error) { + assert(m); + + log_error("Warning! D-Bus connection terminated."); + sd_bus_close(sd_bus_message_get_bus(m)); + + return 0; +} + +static int match_job_removed(sd_bus_message *m, void *userdata, sd_bus_error *error) { + const char *path, *unit, *result; + BusWaitForJobs *d = ASSERT_PTR(userdata); + uint32_t id; + char *found; + int r; + + assert(m); + + r = sd_bus_message_read(m, "uoss", &id, &path, &unit, &result); + if (r < 0) { + bus_log_parse_error(r); + return 0; + } + + found = set_remove(d->jobs, (char*) path); + if (!found) + return 0; + + free(found); + + (void) free_and_strdup(&d->result, empty_to_null(result)); + + (void) free_and_strdup(&d->name, empty_to_null(unit)); + + return 0; +} + +BusWaitForJobs* bus_wait_for_jobs_free(BusWaitForJobs *d) { + if (!d) + return NULL; + + set_free(d->jobs); + + sd_bus_slot_unref(d->slot_disconnected); + sd_bus_slot_unref(d->slot_job_removed); + + sd_bus_unref(d->bus); + + free(d->name); + free(d->result); + + return mfree(d); +} + +int bus_wait_for_jobs_new(sd_bus *bus, BusWaitForJobs **ret) { + _cleanup_(bus_wait_for_jobs_freep) BusWaitForJobs *d = NULL; + int r; + + assert(bus); + assert(ret); + + d = new(BusWaitForJobs, 1); + if (!d) + return -ENOMEM; + + *d = (BusWaitForJobs) { + .bus = sd_bus_ref(bus), + }; + + /* When we are a bus client we match by sender. Direct + * connections OTOH have no initialized sender field, and + * hence we ignore the sender then */ + r = sd_bus_match_signal_async( + bus, + &d->slot_job_removed, + bus->bus_client ? "org.freedesktop.systemd1" : NULL, + "/org/freedesktop/systemd1", + "org.freedesktop.systemd1.Manager", + "JobRemoved", + match_job_removed, NULL, d); + if (r < 0) + return r; + + r = sd_bus_match_signal_async( + bus, + &d->slot_disconnected, + "org.freedesktop.DBus.Local", + NULL, + "org.freedesktop.DBus.Local", + "Disconnected", + match_disconnected, NULL, d); + if (r < 0) + return r; + + *ret = TAKE_PTR(d); + + return 0; +} + +static int bus_process_wait(sd_bus *bus) { + int r; + + for (;;) { + r = sd_bus_process(bus, NULL); + if (r < 0) + return r; + if (r > 0) + return 0; + + r = sd_bus_wait(bus, UINT64_MAX); + if (r < 0) + return r; + } +} + +static int bus_job_get_service_result(BusWaitForJobs *d, char **result) { + _cleanup_free_ char *dbus_path = NULL; + + assert(d); + assert(d->name); + assert(result); + + if (!endswith(d->name, ".service")) + return -EINVAL; + + dbus_path = unit_dbus_path_from_name(d->name); + if (!dbus_path) + return -ENOMEM; + + return sd_bus_get_property_string(d->bus, + "org.freedesktop.systemd1", + dbus_path, + "org.freedesktop.systemd1.Service", + "Result", + NULL, + result); +} + +static void log_job_error_with_service_result(const char* service, const char *result, const char* const* extra_args) { + _cleanup_free_ char *service_shell_quoted = NULL; + const char *systemctl = "systemctl", *journalctl = "journalctl"; + + static const struct { + const char *result, *explanation; + } explanations[] = { + { "resources", "of unavailable resources or another system error" }, + { "protocol", "the service did not take the steps required by its unit configuration" }, + { "timeout", "a timeout was exceeded" }, + { "exit-code", "the control process exited with error code" }, + { "signal", "a fatal signal was delivered to the control process" }, + { "core-dump", "a fatal signal was delivered causing the control process to dump core" }, + { "watchdog", "the service failed to send watchdog ping" }, + { "start-limit", "start of the service was attempted too often" } + }; + + assert(service); + + service_shell_quoted = shell_maybe_quote(service, 0); + + if (!strv_isempty((char**) extra_args)) { + _cleanup_free_ char *t = NULL; + + t = strv_join((char**) extra_args, " "); + systemctl = strjoina("systemctl ", t ?: "<args>"); + journalctl = strjoina("journalctl ", t ?: "<args>"); + } + + if (!isempty(result)) { + size_t i; + + for (i = 0; i < ELEMENTSOF(explanations); ++i) + if (streq(result, explanations[i].result)) + break; + + if (i < ELEMENTSOF(explanations)) { + log_error("Job for %s failed because %s.\n" + "See \"%s status %s\" and \"%s -xeu %s\" for details.\n", + service, + explanations[i].explanation, + systemctl, + service_shell_quoted ?: "<service>", + journalctl, + service_shell_quoted ?: "<service>"); + goto finish; + } + } + + log_error("Job for %s failed.\n" + "See \"%s status %s\" and \"%s -xeu %s\" for details.\n", + service, + systemctl, + service_shell_quoted ?: "<service>", + journalctl, + service_shell_quoted ?: "<service>"); + +finish: + /* For some results maybe additional explanation is required */ + if (streq_ptr(result, "start-limit")) + log_info("To force a start use \"%1$s reset-failed %2$s\"\n" + "followed by \"%1$s start %2$s\" again.", + systemctl, + service_shell_quoted ?: "<service>"); +} + +static int check_wait_response(BusWaitForJobs *d, bool quiet, const char* const* extra_args) { + assert(d); + assert(d->name); + assert(d->result); + + if (!quiet) { + if (streq(d->result, "canceled")) + log_error("Job for %s canceled.", strna(d->name)); + else if (streq(d->result, "timeout")) + log_error("Job for %s timed out.", strna(d->name)); + else if (streq(d->result, "dependency")) + log_error("A dependency job for %s failed. See 'journalctl -xe' for details.", strna(d->name)); + else if (streq(d->result, "invalid")) + log_error("%s is not active, cannot reload.", strna(d->name)); + else if (streq(d->result, "assert")) + log_error("Assertion failed on job for %s.", strna(d->name)); + else if (streq(d->result, "unsupported")) + log_error("Operation on or unit type of %s not supported on this system.", strna(d->name)); + else if (streq(d->result, "collected")) + log_error("Queued job for %s was garbage collected.", strna(d->name)); + else if (streq(d->result, "once")) + log_error("Unit %s was started already once and can't be started again.", strna(d->name)); + else if (!STR_IN_SET(d->result, "done", "skipped")) { + + if (d->name && endswith(d->name, ".service")) { + _cleanup_free_ char *result = NULL; + int q; + + q = bus_job_get_service_result(d, &result); + if (q < 0) + log_debug_errno(q, "Failed to get Result property of unit %s: %m", d->name); + + log_job_error_with_service_result(d->name, result, extra_args); + } else + log_error("Job failed. See \"journalctl -xe\" for details."); + } + } + + if (STR_IN_SET(d->result, "canceled", "collected")) + return -ECANCELED; + else if (streq(d->result, "timeout")) + return -ETIME; + else if (streq(d->result, "dependency")) + return -EIO; + else if (streq(d->result, "invalid")) + return -ENOEXEC; + else if (streq(d->result, "assert")) + return -EPROTO; + else if (streq(d->result, "unsupported")) + return -EOPNOTSUPP; + else if (streq(d->result, "once")) + return -ESTALE; + else if (STR_IN_SET(d->result, "done", "skipped")) + return 0; + + return log_debug_errno(SYNTHETIC_ERRNO(EIO), + "Unexpected job result, assuming server side newer than us: %s", d->result); +} + +int bus_wait_for_jobs(BusWaitForJobs *d, bool quiet, const char* const* extra_args) { + int r = 0; + + assert(d); + + while (!set_isempty(d->jobs)) { + int q; + + q = bus_process_wait(d->bus); + if (q < 0) + return log_error_errno(q, "Failed to wait for response: %m"); + + if (d->name && d->result) { + q = check_wait_response(d, quiet, extra_args); + /* Return the first error as it is most likely to be + * meaningful. */ + if (q < 0 && r == 0) + r = q; + + log_full_errno_zerook(LOG_DEBUG, q, + "Got result %s/%m for job %s", d->result, d->name); + } + + d->name = mfree(d->name); + d->result = mfree(d->result); + } + + return r; +} + +int bus_wait_for_jobs_add(BusWaitForJobs *d, const char *path) { + assert(d); + + return set_put_strdup(&d->jobs, path); +} + +int bus_wait_for_jobs_one(BusWaitForJobs *d, const char *path, bool quiet, const char* const* extra_args) { + int r; + + r = bus_wait_for_jobs_add(d, path); + if (r < 0) + return log_oom(); + + return bus_wait_for_jobs(d, quiet, extra_args); +} |