+#ifdef HAVE_ACL
+static int access_check_var_log_journal(sd_journal *j) {
+ _cleanup_strv_free_ char **g = NULL;
+ bool have_access;
+ int r;
+
+ assert(j);
+
+ have_access = in_group("systemd-journal") > 0;
+
+ if (!have_access) {
+ /* Let's enumerate all groups from the default ACL of
+ * the directory, which generally should allow access
+ * to most journal files too */
+ r = search_acl_groups(&g, "/var/log/journal/", &have_access);
+ if (r < 0)
+ return r;
+ }
+
+ if (!have_access) {
+
+ if (strv_isempty(g))
+ log_notice("Hint: You are currently not seeing messages from other users and the system.\n"
+ " Users in the 'systemd-journal' group can see all messages. Pass -q to\n"
+ " turn off this notice.");
+ else {
+ _cleanup_free_ char *s = NULL;
+
+ r = strv_extend(&g, "systemd-journal");
+ if (r < 0)
+ return log_oom();
+
+ strv_sort(g);
+ strv_uniq(g);
+
+ s = strv_join(g, "', '");
+ if (!s)
+ return log_oom();
+
+ log_notice("Hint: You are currently not seeing messages from other users and the system.\n"
+ " Users in the groups '%s' can see all messages.\n"
+ " Pass -q to turn off this notice.", s);
+ }
+ }
+
+ return 0;
+}
+#endif
+
+static int access_check(sd_journal *j) {
+ Iterator it;
+ void *code;
+ int r = 0;
+
+ assert(j);
+
+ if (set_isempty(j->errors)) {
+ if (hashmap_isempty(j->files))
+ log_notice("No journal files were found.");
+ return 0;
+ }
+
+ if (set_contains(j->errors, INT_TO_PTR(-EACCES))) {
+#ifdef HAVE_ACL
+ /* If /var/log/journal doesn't even exist,
+ * unprivileged users have no access at all */
+ if (access("/var/log/journal", F_OK) < 0 &&
+ geteuid() != 0 &&
+ in_group("systemd-journal") <= 0) {
+ log_error("Unprivileged users cannot access messages, unless persistent log storage is\n"
+ "enabled. Users in the 'systemd-journal' group may always access messages.");
+ return -EACCES;
+ }
+
+ /* If /var/log/journal exists, try to pring a nice
+ notice if the user lacks access to it */
+ if (!arg_quiet && geteuid() != 0) {
+ r = access_check_var_log_journal(j);
+ if (r < 0)
+ return r;
+ }
+#else
+ if (geteuid() != 0 && in_group("systemd-journal") <= 0) {
+ log_error("Unprivileged users cannot access messages. Users in the 'systemd-journal' group\n"
+ "group may access messages.");
+ return -EACCES;
+ }
+#endif
+
+ if (hashmap_isempty(j->files)) {
+ log_error("No journal files were opened due to insufficient permissions.");
+ r = -EACCES;
+ }
+ }
+
+ SET_FOREACH(code, j->errors, it) {
+ int err;
+
+ err = -PTR_TO_INT(code);
+ assert(err > 0);
+
+ if (err != EACCES)
+ log_warning("Error was encountered while opening journal files: %s",
+ strerror(err));
+ }
+
+ return r;
+}
+