journalctl: improve hint about lack of access for --user-unit=...

When running journalctl --user-unit=foo as an unprivileged user we could get
the usual hint:
Hint: You are currently not seeing messages from the system and other users.
      Users in groups 'adm', 'systemd-journal', 'wheel' can see all messages.
      ...
But with --user-unit our filter is:
(((_UID=0 OR _UID=1000) AND OBJECT_SYSTEMD_USER_UNIT=foo.service) OR
 ((_UID=0 OR _UID=1000) AND COREDUMP_USER_UNIT=foo.service) OR
 (_UID=1000 AND USER_UNIT=foo.service) OR
 (_UID=1000 AND _SYSTEMD_USER_UNIT=foo.service))
so we would never see messages from other users.

We could still see messages from the system. In fact, on my machine the
only messages with OBJECT_SYSTEMD_USER_UNIT= are from the system:
journalctl  $(journalctl -F OBJECT_SYSTEMD_USER_UNIT|sed 's/.*/OBJECT_SYSTEMD_USER_UNIT=\0/')

Thus, a more correct hint is that we cannot see messages from the system.
Make it so.

Fixes #7887.

1 files changed, 3 insertions, 3 deletions

diff --git a/src/journal/journalctl.c b/src/journal/journalctl.c
index 0aa4c1f772..02715142e9 100644
--- a/src/journal/journalctl.c
+++ b/src/journal/journalctl.c
@@ -972,8 +972,7 @@ static int parse_argv(int argc, char *argv[]) {
                 return -EINVAL;
         }
 
-        if (!strv_isempty(arg_system_units) && (arg_journal_type == SD_JOURNAL_CURRENT_USER)) {
-
+        if (!strv_isempty(arg_system_units) && arg_journal_type == SD_JOURNAL_CURRENT_USER) {
                 /* Specifying --user and --unit= at the same time makes no sense (as the former excludes the user
                  * journal, but the latter excludes the system journal, thus resulting in empty output). Let's be nice
                  * to users, and automatically turn --unit= into --user-unit= if combined with --user. */
@@ -2241,7 +2240,8 @@ int main(int argc, char *argv[]) {
                 goto finish;
         }
 
-        r = journal_access_check_and_warn(j, arg_quiet);
+        r = journal_access_check_and_warn(j, arg_quiet,
+                                          !(arg_journal_type == SD_JOURNAL_CURRENT_USER || arg_user_units));
         if (r < 0)
                 goto finish;