Better error message when hibernating without swap

[Nikratio]

(originallly filed as https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=771491)

When attempting to hibernate without an active swap partition, I get:

[0] nikratio@kosh:~$ systemctl hibernate
Failed to execute operation: Sleep verb not supported
Failed to start hibernate.target: Access denied

and as root:

[0] root@kosh:~# systemctl hibernate
A dependency job for hibernate.target failed. See 'journalctl -xn' for details.
[1] root@kosh:~# journalctl -xn
-- Logs begin at Sat 2014-11-29 19:59:30 PST, end at Sat 2014-11-29 20:16:20 PST. --
Nov 29 20:16:20 kosh kernel: brcmsmac bcma0:0: brcms_ops_bss_info_changed: qos enabled: true (implement)
Nov 29 20:16:20 kosh kernel: wlan0: associated
Nov 29 20:16:20 kosh NetworkManager[827]: <info> (wlan0): supplicant interface state: authenticating -> associating
Nov 29 20:16:20 kosh NetworkManager[827]: <info> (wlan0): supplicant interface state: associating -> associated
Nov 29 20:16:20 kosh NetworkManager[827]: <info> (wlan0): supplicant interface state: associated -> 4-way handshake
Nov 29 20:16:20 kosh wpa_supplicant[1456]: wlan0: WPA: Key negotiation completed with 00:1f:33:be:9a:c4 [PTK=CCMP GTK=TKIP]
Nov 29 20:16:20 kosh wpa_supplicant[1456]: wlan0: CTRL-EVENT-CONNECTED - Connection to 00:1f:33:be:9a:c4 completed [id=0 id_str
Nov 29 20:16:20 kosh kernel: [96B blob data]
Nov 29 20:16:20 kosh NetworkManager[827]: <info> (wlan0): supplicant interface state: 4-way handshake -> completed
Nov 29 20:16:20 kosh NetworkManager[827]: <info> (wlan0): roamed from BSSID (none) ((none)) to 00:1F:33:BE:9A:C4 (fred clever)
[0] root@kosh:~# systemctl status systemd-hibernate
● systemd-hibernate.service - Hibernate
   Loaded: loaded (/lib/systemd/system/systemd-hibernate.service; static)
   Active: failed (Result: exit-code) since Sat 2014-11-29 20:16:19 PST; 15s ago
     Docs: man:systemd-suspend.service(8)
  Process: 4627 ExecStart=/lib/systemd/systemd-sleep hibernate (code=exited, status=1/FAILURE)
 Main PID: 4627 (code=exited, status=1/FAILURE)

Nov 29 20:16:16 kosh systemd-sleep[4627]: Suspending system...
Nov 29 20:16:19 kosh systemd[1]: systemd-hibernate.service: main process exited, code=exited, status=1/FAILURE
Nov 29 20:16:19 kosh systemd[1]: Failed to start Hibernate.
Nov 29 20:16:19 kosh systemd[1]: Unit systemd-hibernate.service entered failed state.

None of this gives any indication of the real problem. It'd be great if the error message could be improved.

[poettering]

Fixed in b71c975 since a long time.