"gsup.hlr.123456789012345.imsi" -> "gsup.hlr" "123456789012345" imsi
"gsup.hlr.1.imsi" -> rc = -5
"sip.voice.1.msisdn" -> "sip.voice" "1" msisdn
"a.b.c.imsi" -> rc = -5
"" -> rc = -2
"." -> rc = -3
"..." -> rc = -4
"....." -> rc = -4
".....1.msisdn" -> "...." "1" msisdn
"fofdndsf. d.ads ofdsf. ads.kj.1243455132.msisdn" -> "fofdndsf. d.ads ofdsf. ads.kj" "1243455132" msisdn
"foo.12345678901234567890.imsi" -> rc = -11
"gsup.hlr.123456789012345.what" -> rc = -7
NULL -> rc = -1
"blarg" -> rc = -2
"blarg." -> rc = -3
"blarg.1." -> rc = -4
"blarg.1.msisdn" -> "blarg" "1" msisdn
"blarg.1.msisdn." -> rc = -4
".1.msisdn" -> rc = -3
"1.msisdn" -> rc = -3
"qwertyuiopasdfghjklzxcvbnmqwertyuiopasdfghjklzxcvbnmqwertyuiopasdfghjklzxcvbnmm.1.msisdn" -> rc = -11
"qwerty.1.qwertyuiopasdfghjklzxcvbnmqwertyuiopasdfghjklzxcvbnmqwertyuiopasdfghjklzxcvbnmm" -> rc = -7