systemctl: make `--timestamp=` affect the `show` verb as well

Currently the `--timestamp=` option has no effect on timestamps shown by
`systemctl show`, let's fix that.

Spotted in #22567.

Before:
```
$ systemctl show --timestamp=us+utc systemd-journald | grep Timestamp=
ExecMainStartTimestamp=Sat 2021-12-11 15:25:57 CET
StateChangeTimestamp=Sat 2021-12-11 15:25:57 CET
InactiveExitTimestamp=Sat 2021-12-11 15:25:57 CET
ActiveEnterTimestamp=Sat 2021-12-11 15:25:57 CET
ActiveExitTimestamp=Sat 2021-12-11 15:25:57 CET
InactiveEnterTimestamp=Sat 2021-12-11 15:25:57 CET
ConditionTimestamp=Sat 2021-12-11 15:25:57 CET
AssertTimestamp=Sat 2021-12-11 15:25:57 CET
```

After:
```
$ systemctl show --timestamp=us+utc systemd-journald | grep Timestamp=
ExecMainStartTimestamp=Sat 2021-12-11 14:25:57.177848 UTC
StateChangeTimestamp=Sat 2021-12-11 14:25:57.196714 UTC
InactiveExitTimestamp=Sat 2021-12-11 14:25:57.177871 UTC
ActiveEnterTimestamp=Sat 2021-12-11 14:25:57.196714 UTC
ActiveExitTimestamp=Sat 2021-12-11 14:25:57.144677 UTC
InactiveEnterTimestamp=Sat 2021-12-11 14:25:57.176331 UTC
ConditionTimestamp=Sat 2021-12-11 14:25:57.176980 UTC
AssertTimestamp=Sat 2021-12-11 14:25:57.176980 UTC

```

diff --git a/src/systemctl/systemctl-show.c b/src/systemctl/systemctl-show.c
index 0985a452ec3745eec4eeb5d1e9e440ce49adebf2..dca6d6f4c4520c951970e5482e3cf050504337c7 100644 (file)
--- a/src/systemctl/systemctl-show.c
+++ b/src/systemctl/systemctl-show.c
@@ -989,6 +989,20 @@ static int print_property(const char *name, const char *expected_value, sd_bus_m
                 }
                 break;
 
+        case SD_BUS_TYPE_UINT64:
+                if (endswith(name, "Timestamp")) {
+                        uint64_t timestamp;
+
+                        r = sd_bus_message_read_basic(m, bus_type, &timestamp);
+                        if (r < 0)
+                                return r;
+
+                        bus_print_property_value(name, expected_value, flags, FORMAT_TIMESTAMP_STYLE(timestamp, arg_timestamp_style));
+
+                        return 1;
+                }
+                break;
+
         case SD_BUS_TYPE_STRUCT:
 
                 if (contents[0] == SD_BUS_TYPE_UINT32 && streq(name, "Job")) {