+int add_matches_for_user_unit(sd_journal *j, const char *unit, uid_t uid) {
+ int r;
+ char *m1, *m2, *m3, *m4;
+ char muid[sizeof("_UID=") + DECIMAL_STR_MAX(uid_t)];
+
+ assert(j);
+ assert(unit);
+
+ m1 = strappenda("_SYSTEMD_USER_UNIT=", unit);
+ m2 = strappenda("USER_UNIT=", unit);
+ m3 = strappenda("COREDUMP_USER_UNIT=", unit);
+ m4 = strappenda("OBJECT_SYSTEMD_USER_UNIT=", unit);
+ sprintf(muid, "_UID="UID_FMT, uid);
+
+ (void) (
+ /* Look for messages from the user service itself */
+ (r = sd_journal_add_match(j, m1, 0)) ||
+ (r = sd_journal_add_match(j, muid, 0)) ||
+
+ /* Look for messages from systemd about this service */
+ (r = sd_journal_add_disjunction(j)) ||
+ (r = sd_journal_add_match(j, m2, 0)) ||
+ (r = sd_journal_add_match(j, muid, 0)) ||
+
+ /* Look for coredumps of the service */
+ (r = sd_journal_add_disjunction(j)) ||
+ (r = sd_journal_add_match(j, m3, 0)) ||
+ (r = sd_journal_add_match(j, muid, 0)) ||
+ (r = sd_journal_add_match(j, "_UID=0", 0)) ||
+
+ /* Look for messages from authorized daemons about this service */
+ (r = sd_journal_add_disjunction(j)) ||
+ (r = sd_journal_add_match(j, m4, 0)) ||
+ (r = sd_journal_add_match(j, muid, 0)) ||
+ (r = sd_journal_add_match(j, "_UID=0", 0))
+ );
+
+ if (r == 0 && endswith(unit, ".slice")) {
+ char *m5 = strappend("_SYSTEMD_SLICE=", unit);
+
+ /* Show all messages belonging to a slice */
+ (void)(
+ (r = sd_journal_add_disjunction(j)) ||
+ (r = sd_journal_add_match(j, m5, 0)) ||
+ (r = sd_journal_add_match(j, muid, 0))
+ );
+ }
+
+ return r;
+}
+
+static int get_boot_id_for_machine(const char *machine, sd_id128_t *boot_id) {
+ _cleanup_close_pair_ int pair[2] = { -1, -1 };
+ _cleanup_close_ int pidnsfd = -1, mntnsfd = -1, rootfd = -1;
+ pid_t pid, child;
+ siginfo_t si;
+ char buf[37];
+ ssize_t k;
+ int r;
+
+ assert(machine);
+ assert(boot_id);
+
+ if (!machine_name_is_valid(machine))
+ return -EINVAL;
+
+ r = container_get_leader(machine, &pid);
+ if (r < 0)
+ return r;
+
+ r = namespace_open(pid, &pidnsfd, &mntnsfd, NULL, &rootfd);
+ if (r < 0)
+ return r;
+
+ if (socketpair(AF_UNIX, SOCK_DGRAM, 0, pair) < 0)
+ return -errno;
+
+ child = fork();
+ if (child < 0)
+ return -errno;
+
+ if (child == 0) {
+ int fd;
+
+ pair[0] = safe_close(pair[0]);
+
+ r = namespace_enter(pidnsfd, mntnsfd, -1, rootfd);
+ if (r < 0)
+ _exit(EXIT_FAILURE);
+
+ fd = open("/proc/sys/kernel/random/boot_id", O_RDONLY|O_CLOEXEC|O_NOCTTY);
+ if (fd < 0)
+ _exit(EXIT_FAILURE);
+
+ k = loop_read(fd, buf, 36, false);
+ safe_close(fd);
+ if (k != 36)
+ _exit(EXIT_FAILURE);
+
+ k = send(pair[1], buf, 36, MSG_NOSIGNAL);
+ if (k != 36)
+ _exit(EXIT_FAILURE);
+
+ _exit(EXIT_SUCCESS);
+ }
+
+ pair[1] = safe_close(pair[1]);
+
+ r = wait_for_terminate(child, &si);
+ if (r < 0 || si.si_code != CLD_EXITED || si.si_status != EXIT_SUCCESS)
+ return r < 0 ? r : -EIO;
+
+ k = recv(pair[0], buf, 36, 0);
+ if (k != 36)
+ return -EIO;
+
+ buf[36] = 0;
+ r = sd_id128_from_string(buf, boot_id);
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
+int add_match_this_boot(sd_journal *j, const char *machine) {
+ char match[9+32+1] = "_BOOT_ID=";
+ sd_id128_t boot_id;
+ int r;
+
+ assert(j);
+
+ if (machine) {
+ r = get_boot_id_for_machine(machine, &boot_id);
+ if (r < 0)
+ return log_error_errno(r, "Failed to get boot id of container %s: %m", machine);
+ } else {
+ r = sd_id128_get_boot(&boot_id);
+ if (r < 0)
+ return log_error_errno(r, "Failed to get boot id: %m");
+ }
+
+ sd_id128_to_string(boot_id, match + 9);
+ r = sd_journal_add_match(j, match, strlen(match));
+ if (r < 0)
+ return log_error_errno(r, "Failed to add match: %m");
+
+ r = sd_journal_add_conjunction(j);
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
+int show_journal_by_unit(
+ FILE *f,
+ const char *unit,
+ OutputMode mode,
+ unsigned n_columns,
+ usec_t not_before,
+ unsigned how_many,
+ uid_t uid,
+ OutputFlags flags,
+ int journal_open_flags,
+ bool system_unit,
+ bool *ellipsized) {
+
+ _cleanup_journal_close_ sd_journal*j = NULL;
+ int r;
+
+ assert(mode >= 0);
+ assert(mode < _OUTPUT_MODE_MAX);
+ assert(unit);
+
+ if (how_many <= 0)
+ return 0;
+
+ r = sd_journal_open(&j, journal_open_flags);
+ if (r < 0)
+ return r;
+
+ r = add_match_this_boot(j, NULL);
+ if (r < 0)
+ return r;
+
+ if (system_unit)
+ r = add_matches_for_unit(j, unit);
+ else
+ r = add_matches_for_user_unit(j, unit, uid);
+ if (r < 0)
+ return r;
+
+ if (_unlikely_(log_get_max_level() >= LOG_DEBUG)) {
+ _cleanup_free_ char *filter;
+
+ filter = journal_make_match_string(j);
+ log_debug("Journal filter: %s", filter);
+ }
+
+ return show_journal(f, j, mode, n_columns, not_before, how_many, flags, ellipsized);
+}
+