tree b36b740fa2a3f8b49cf42baa49eee7c6911e1a08
parent 705b61bcb795490e265027d0b45499b87dd65e12
author Stefan Sperling <ssperling@sysmocom.de> 1544182221 +0100
committer Stefan Sperling <stsp@stsp.name> 1544458326 +0000

display last location update timestamp in vty

Read the subscriber's last location update timestamp from the
database and display it in the output of 'show subscriber'.

For example:
  OsmoHLR> show subscriber id 1
      ID: 1
      IMSI: 123456789000000
      MSISDN: 543210123456789
      VLR number: 712
      SGSN number: 5952
      last LU seen: Fri Dec  7 11:30:51 2018 UTC

While the database stores the timestamp as a string, we
convert the timestamp into time_t for internal use.
This allows for flexible potential use of the timestamp
in contexts other than the VTY in the future.

The timestamp displayed in the VTY is created with ctime_r(3).
It does not match the format of the raw string in the database:
  sqlite> select id,last_lu_seen from subscriber;
  1|2018-12-07 11:30:51

Related: OS#2838
Change-Id: Ie180c434f02ffec0d4b2f651a73258a8126b2e1a