logind: add code for UTMP wall messages

Add a timer to print UTMP wall messages so that it repeatedly informs users
about a scheduled shutdown:

 * every 1 minute with less than 10 minutes to go
 * every 15 minutes with less than 60 minutes to go
 * every 30 minutes with less than 180 minutes (3 hours) to go
 * every 60 minutes if more than that to go

This functionality only active if the .EnableWallMessages DBus property
is set to true. Also, a custom string can be added to the wall message,
set through the WallMessagePrefix property.

1 files changed, 9 insertions, 0 deletions

diff --git a/src/login/logind.h b/src/login/logind.h
index cd2bdc05d2..1c60b01860 100644
--- a/src/login/logind.h
+++ b/src/login/logind.h
@@ -100,6 +100,12 @@ struct Manager {
         char *scheduled_shutdown_type;
         usec_t scheduled_shutdown_timeout;
         sd_event_source *scheduled_shutdown_timeout_source;
+        uid_t scheduled_shutdown_uid;
+        char *scheduled_shutdown_tty;
+
+        char *wall_message;
+        unsigned enable_wall_messages;
+        sd_event_source *wall_message_timeout_source;
 
         sd_event_source *idle_action_event_source;
         usec_t idle_action_usec;
@@ -185,3 +191,6 @@ int config_parse_tmpfs_size(const char *unit, const char *filename, unsigned lin
 int manager_get_session_from_creds(Manager *m, sd_bus_message *message, const char *name, sd_bus_error *error, Session **ret);
 int manager_get_user_from_creds(Manager *m, sd_bus_message *message, uid_t uid, sd_bus_error *error, User **ret);
 int manager_get_seat_from_creds(Manager *m, sd_bus_message *message, const char *name, sd_bus_error *error, Seat **ret);
+
+int manager_setup_wall_message_timer(Manager *m);
+bool logind_wall_tty_filter(const char *tty, void *userdata);