add osmo_tdef API, originally adopted from osmo-bsc T_def

Move T_def from osmo-bsc to libosmocore as osmo_tdef. Adjust naming to be more
consistent. Upgrade to first class API:
- add timer grouping
- add generic vty support
- add mising API doc
- add C test
- add VTY transcript tests, also as examples for using the API

From osmo_fsm_inst_state_chg() API doc, cross reference to osmo_tdef API.

The root reason for moving to libosmocore is that I want to use the
mgw_endpoint_fsm in osmo-msc for inter-MSC handover, and hence want to move the
FSM to libosmo-mgcp-client. This FSM uses the T_def from osmo-bsc. Though the
mgw_endpoint_fsm's use of T_def is minimal, I intend to use the osmo_tdef API
in osmo-msc (and probably elsewhere) as well. libosmocore is the most sensible
place for this.

osmo_tdef provides:

- a list of Tnnnn (GSM) timers with description, unit and default value.
- vty UI to allow users to configure non-default timeouts.
- API to tie T timers to osmo_fsm states and set them on state transitions.

- a few standard units (minute, second, millisecond) as well as a custom unit
  (which relies on the timer's human readable description to indicate the
  meaning of the value).
- conversion for standard units: for example, some GSM timers are defined in
  minutes, while our FSM definitions need timeouts in seconds. Conversion is
  for convenience only and can be easily avoided via the custom unit.

By keeping separate osmo_tdef arrays, several groups of timers can be kept
separately. The VTY tests in tests/tdef/ showcase different schemes:

- tests/vty/tdef_vty_test_config_root.c:
  Keep several timer definitions in separately named groups: showcase the
  osmo_tdef_vty_groups*() API. Each timer group exists exactly once.

- tests/vty/tdef_vty_test_config_subnode.c:
  Keep a single list of timers without separate grouping.
  Put this list on a specific subnode below the CONFIG_NODE.
  There could be several separate subnodes with timers like this, i.e.
  continuing from this example, sets timers could be separated by placing
  timers in specific config subnodes instead of using the global group name.

- tests/vty/tdef_vty_test_dynamic.c:
  Dynamically allocate timer definitions per each new created object.
  Thus there can be an arbitrary number of independent timer definitions, one
  per allocated object.

T_def was introduced during the recent osmo-bsc refactoring for inter-BSC
handover, and has proven useful:

- without osmo_tdef, each invocation of osmo_fsm_inst_state_chg() needs to be
  programmed with the right timeout value, for all code paths that invoke this
  state change. It is a likely source of errors to get one of them wrong.  By
  defining a T timer exactly for an FSM state, the caller can merely invoke the
  state change and trust on the original state definition to apply the correct
  timeout.

- it is helpful to have a standardized config file UI to provide user
  configurable timeouts, instead of inventing new VTY commands for each
  separate application of T timer numbers.

Change-Id: Ibd6b1ed7f1bd6e1f2e0fde53352055a4468f23e5

1 files changed, 292 insertions, 0 deletions

diff --git a/tests/tdef/tdef_vty_test_config_root.vty b/tests/tdef/tdef_vty_test_config_root.vty
new file mode 100644
index 00000000..12876a68
--- /dev/null
+++ b/tests/tdef/tdef_vty_test_config_root.vty
@@ -0,0 +1,292 @@
+tdef_vty_test> list
+...
+  show timer [(tea|test|software)] [TNNNN]
+...
+
+tdef_vty_test> show timer ?
+  [tea]       Tea time
+  [test]      Test timers
+  [software]  Typical software development cycle
+
+tdef_vty_test> show timer test ?
+  [TNNNN]  T-number, optionally preceded by 't' or 'T'.
+
+tdef_vty_test> show timer
+tea: T1 = 50 s	Water Boiling Timeout (default: 50 s)
+tea: T2 = 300 s	Tea brewing (default: 300 s)
+tea: T3 = 5 m	Let tea cool down before drinking (default: 5 m)
+tea: T4 = 20 m	Forgot to drink tea while it's warm (default: 20 m)
+test: T1 = 100 s	Testing a hundred seconds (default: 100 s)
+test: T2 = 100 ms	Testing a hundred milliseconds (default: 100 ms)
+test: T3 = 100 m	Testing a hundred minutes (default: 100 m)
+test: T4 = 100	Testing a hundred potatoes (default: 100)
+test: T2147483647 = 18446744073709551615 m	Very large (default: 18446744073709551615 m)
+test: T-23 = 18446744073709551601 s	Negative T number (default: 18446744073709551601 s)
+software: T1 = 30 m	Write code (default: 30 m)
+software: T2 = 20 ms	Hit segfault (default: 20 ms)
+software: T3 = 480 m	Fix bugs (default: 480 m)
+
+tdef_vty_test> enable
+tdef_vty_test# show timer
+tea: T1 = 50 s	Water Boiling Timeout (default: 50 s)
+tea: T2 = 300 s	Tea brewing (default: 300 s)
+tea: T3 = 5 m	Let tea cool down before drinking (default: 5 m)
+tea: T4 = 20 m	Forgot to drink tea while it's warm (default: 20 m)
+test: T1 = 100 s	Testing a hundred seconds (default: 100 s)
+test: T2 = 100 ms	Testing a hundred milliseconds (default: 100 ms)
+test: T3 = 100 m	Testing a hundred minutes (default: 100 m)
+test: T4 = 100	Testing a hundred potatoes (default: 100)
+test: T2147483647 = 18446744073709551615 m	Very large (default: 18446744073709551615 m)
+test: T-23 = 18446744073709551601 s	Negative T number (default: 18446744073709551601 s)
+software: T1 = 30 m	Write code (default: 30 m)
+software: T2 = 20 ms	Hit segfault (default: 20 ms)
+software: T3 = 480 m	Fix bugs (default: 480 m)
+
+tdef_vty_test# configure terminal
+
+tdef_vty_test(config)# show running-config
+... !timer
+
+tdef_vty_test(config)# list
+...
+  timer [(tea|test|software)] [TNNNN] [(<0-2147483647>|default)]
+...
+
+tdef_vty_test(config)# timer ?
+  [tea]       Tea time
+  [test]      Test timers
+  [software]  Typical software development cycle
+
+tdef_vty_test(config)# timer sof T123 ?
+  [<0-2147483647>]  New timer value
+  [default]         Set to default timer value
+
+tdef_vty_test(config)# timer sof T123 ?
+  [<0-2147483647>]  New timer value
+  [default]         Set to default timer value
+
+tdef_vty_test(config)# timer test ?
+  [TNNNN]  T-number, optionally preceded by 't' or 'T'.
+
+tdef_vty_test(config)# timer test t2 ?
+  [<0-2147483647>]  New timer value
+  [default]         Set to default timer value
+
+tdef_vty_test(config)# do show timer
+tea: T1 = 50 s	Water Boiling Timeout (default: 50 s)
+tea: T2 = 300 s	Tea brewing (default: 300 s)
+tea: T3 = 5 m	Let tea cool down before drinking (default: 5 m)
+tea: T4 = 20 m	Forgot to drink tea while it's warm (default: 20 m)
+test: T1 = 100 s	Testing a hundred seconds (default: 100 s)
+test: T2 = 100 ms	Testing a hundred milliseconds (default: 100 ms)
+test: T3 = 100 m	Testing a hundred minutes (default: 100 m)
+test: T4 = 100	Testing a hundred potatoes (default: 100)
+test: T2147483647 = 18446744073709551615 m	Very large (default: 18446744073709551615 m)
+test: T-23 = 18446744073709551601 s	Negative T number (default: 18446744073709551601 s)
+software: T1 = 30 m	Write code (default: 30 m)
+software: T2 = 20 ms	Hit segfault (default: 20 ms)
+software: T3 = 480 m	Fix bugs (default: 480 m)
+
+tdef_vty_test(config)# do show timer tea
+tea: T1 = 50 s	Water Boiling Timeout (default: 50 s)
+tea: T2 = 300 s	Tea brewing (default: 300 s)
+tea: T3 = 5 m	Let tea cool down before drinking (default: 5 m)
+tea: T4 = 20 m	Forgot to drink tea while it's warm (default: 20 m)
+
+tdef_vty_test(config)# do show timer tea 2
+tea: T2 = 300 s	Tea brewing (default: 300 s)
+
+tdef_vty_test(config)# do show timer tea t2
+tea: T2 = 300 s	Tea brewing (default: 300 s)
+
+tdef_vty_test(config)# do show timer tea T2
+tea: T2 = 300 s	Tea brewing (default: 300 s)
+
+tdef_vty_test(config)# do show timer tea T5
+% No such timer: T5
+
+tdef_vty_test(config)# do show timer tea T0
+% No such timer: T0
+
+tdef_vty_test(config)# do show timer tea T-123
+% No such timer: T-123
+
+tdef_vty_test(config)# do show timer t
+tea: T1 = 50 s	Water Boiling Timeout (default: 50 s)
+tea: T2 = 300 s	Tea brewing (default: 300 s)
+tea: T3 = 5 m	Let tea cool down before drinking (default: 5 m)
+tea: T4 = 20 m	Forgot to drink tea while it's warm (default: 20 m)
+test: T1 = 100 s	Testing a hundred seconds (default: 100 s)
+test: T2 = 100 ms	Testing a hundred milliseconds (default: 100 ms)
+test: T3 = 100 m	Testing a hundred minutes (default: 100 m)
+test: T4 = 100	Testing a hundred potatoes (default: 100)
+test: T2147483647 = 18446744073709551615 m	Very large (default: 18446744073709551615 m)
+test: T-23 = 18446744073709551601 s	Negative T number (default: 18446744073709551601 s)
+
+tdef_vty_test(config)# do show timer te
+tea: T1 = 50 s	Water Boiling Timeout (default: 50 s)
+tea: T2 = 300 s	Tea brewing (default: 300 s)
+tea: T3 = 5 m	Let tea cool down before drinking (default: 5 m)
+tea: T4 = 20 m	Forgot to drink tea while it's warm (default: 20 m)
+test: T1 = 100 s	Testing a hundred seconds (default: 100 s)
+test: T2 = 100 ms	Testing a hundred milliseconds (default: 100 ms)
+test: T3 = 100 m	Testing a hundred minutes (default: 100 m)
+test: T4 = 100	Testing a hundred potatoes (default: 100)
+test: T2147483647 = 18446744073709551615 m	Very large (default: 18446744073709551615 m)
+test: T-23 = 18446744073709551601 s	Negative T number (default: 18446744073709551601 s)
+
+tdef_vty_test(config)# do show timer te T2
+tea: T2 = 300 s	Tea brewing (default: 300 s)
+test: T2 = 100 ms	Testing a hundred milliseconds (default: 100 ms)
+
+
+tdef_vty_test(config)# timer tea 3 30
+tdef_vty_test(config)# timer tea T3
+tea: T3 = 30 m	Let tea cool down before drinking (default: 5 m)
+
+tdef_vty_test(config)# timer tea t3 31
+tdef_vty_test(config)# timer tea T3
+tea: T3 = 31 m	Let tea cool down before drinking (default: 5 m)
+
+tdef_vty_test(config)# timer tea T3 32
+tdef_vty_test(config)# timer tea T3
+tea: T3 = 32 m	Let tea cool down before drinking (default: 5 m)
+
+tdef_vty_test(config)# timer tea T-123 99
+% No such timer: T-123
+
+tdef_vty_test(config)# timer tea T0 0
+% No such timer: T0
+
+tdef_vty_test(config)# timer tea T123 default
+% No such timer: T123
+
+tdef_vty_test(config)# timer tea
+tea: T1 = 50 s	Water Boiling Timeout (default: 50 s)
+tea: T2 = 300 s	Tea brewing (default: 300 s)
+tea: T3 = 32 m	Let tea cool down before drinking (default: 5 m)
+tea: T4 = 20 m	Forgot to drink tea while it's warm (default: 20 m)
+
+tdef_vty_test(config)# timer t
+tea: T1 = 50 s	Water Boiling Timeout (default: 50 s)
+tea: T2 = 300 s	Tea brewing (default: 300 s)
+tea: T3 = 32 m	Let tea cool down before drinking (default: 5 m)
+tea: T4 = 20 m	Forgot to drink tea while it's warm (default: 20 m)
+test: T1 = 100 s	Testing a hundred seconds (default: 100 s)
+test: T2 = 100 ms	Testing a hundred milliseconds (default: 100 ms)
+test: T3 = 100 m	Testing a hundred minutes (default: 100 m)
+test: T4 = 100	Testing a hundred potatoes (default: 100)
+test: T2147483647 = 18446744073709551615 m	Very large (default: 18446744073709551615 m)
+test: T-23 = 18446744073709551601 s	Negative T number (default: 18446744073709551601 s)
+
+tdef_vty_test(config)# timer te T2
+tea: T2 = 300 s	Tea brewing (default: 300 s)
+test: T2 = 100 ms	Testing a hundred milliseconds (default: 100 ms)
+
+tdef_vty_test(config)# timer test T2 100
+
+tdef_vty_test(config)# timer tes T2 100
+% Error: no timers found
+
+tdef_vty_test(config)# timer te T2 100
+% Error: no timers found
+
+
+tdef_vty_test(config)# do show timer software
+software: T1 = 30 m	Write code (default: 30 m)
+software: T2 = 20 ms	Hit segfault (default: 20 ms)
+software: T3 = 480 m	Fix bugs (default: 480 m)
+
+tdef_vty_test(config)# do show timer software 1
+software: T1 = 30 m	Write code (default: 30 m)
+
+tdef_vty_test(config)# do show timer software t1
+software: T1 = 30 m	Write code (default: 30 m)
+
+tdef_vty_test(config)# do show timer software T1
+software: T1 = 30 m	Write code (default: 30 m)
+
+tdef_vty_test(config)# do show timer software T99
+% No such timer: T99
+
+tdef_vty_test(config)# do show timer software T-123123
+% No such timer: T-123123
+
+tdef_vty_test(config)# do show timer software T0
+% No such timer: T0
+
+tdef_vty_test(config)# timer software 1 11
+tdef_vty_test(config)# timer software T1
+software: T1 = 11 m	Write code (default: 30 m)
+
+tdef_vty_test(config)# timer software t1 12
+tdef_vty_test(config)# timer software T1
+software: T1 = 12 m	Write code (default: 30 m)
+
+tdef_vty_test(config)# timer software T1 13
+tdef_vty_test(config)# timer software T2 0
+tdef_vty_test(config)# timer software
+software: T1 = 13 m	Write code (default: 30 m)
+software: T2 = 0 ms	Hit segfault (default: 20 ms)
+software: T3 = 480 m	Fix bugs (default: 480 m)
+
+tdef_vty_test(config)# timer softw
+software: T1 = 13 m	Write code (default: 30 m)
+software: T2 = 0 ms	Hit segfault (default: 20 ms)
+software: T3 = 480 m	Fix bugs (default: 480 m)
+
+tdef_vty_test(config)# timer softw T3
+software: T3 = 480 m	Fix bugs (default: 480 m)
+
+tdef_vty_test(config)# timer softw T3 23
+% Error: no timers found
+
+tdef_vty_test(config)# timer
+tea: T1 = 50 s	Water Boiling Timeout (default: 50 s)
+tea: T2 = 300 s	Tea brewing (default: 300 s)
+tea: T3 = 32 m	Let tea cool down before drinking (default: 5 m)
+tea: T4 = 20 m	Forgot to drink tea while it's warm (default: 20 m)
+test: T1 = 100 s	Testing a hundred seconds (default: 100 s)
+test: T2 = 100 ms	Testing a hundred milliseconds (default: 100 ms)
+test: T3 = 100 m	Testing a hundred minutes (default: 100 m)
+test: T4 = 100	Testing a hundred potatoes (default: 100)
+test: T2147483647 = 18446744073709551615 m	Very large (default: 18446744073709551615 m)
+test: T-23 = 18446744073709551601 s	Negative T number (default: 18446744073709551601 s)
+software: T1 = 13 m	Write code (default: 30 m)
+software: T2 = 0 ms	Hit segfault (default: 20 ms)
+software: T3 = 480 m	Fix bugs (default: 480 m)
+
+tdef_vty_test(config)# do show timer
+tea: T1 = 50 s	Water Boiling Timeout (default: 50 s)
+tea: T2 = 300 s	Tea brewing (default: 300 s)
+tea: T3 = 32 m	Let tea cool down before drinking (default: 5 m)
+tea: T4 = 20 m	Forgot to drink tea while it's warm (default: 20 m)
+test: T1 = 100 s	Testing a hundred seconds (default: 100 s)
+test: T2 = 100 ms	Testing a hundred milliseconds (default: 100 ms)
+test: T3 = 100 m	Testing a hundred minutes (default: 100 m)
+test: T4 = 100	Testing a hundred potatoes (default: 100)
+test: T2147483647 = 18446744073709551615 m	Very large (default: 18446744073709551615 m)
+test: T-23 = 18446744073709551601 s	Negative T number (default: 18446744073709551601 s)
+software: T1 = 13 m	Write code (default: 30 m)
+software: T2 = 0 ms	Hit segfault (default: 20 ms)
+software: T3 = 480 m	Fix bugs (default: 480 m)
+
+tdef_vty_test(config)# show running-config
+... !timer
+timer tea T3 32
+timer software T1 13
+timer software T2 0
+... !timer
+
+tdef_vty_test(config)# timer tea T3 default
+tdef_vty_test(config)# timer software T1 default
+tdef_vty_test(config)# show running-config
+... !timer
+timer software T2 0
+... !timer
+
+tdef_vty_test(config)# timer softw 2 default
+% Error: no timers found
+tdef_vty_test(config)# timer software 2 default
+tdef_vty_test(config)# show running-config
+... !timer