fi->T values are int, i.e. can be negative. Do not log them as unsigned, but
define a distinct timer class "Xnnnn" for negative T values: i.e. for T == -1,
print "Timeout of X1" instead of "Timeout of T4294967295".
The negative T timer number space is useful to distinguish freely invented
timers from proper 3GPP defined T numbers. So far I was using numbers like
T993210 or T9999 for invented T, but X1, X2 etc. is a better solution. This way
we can make sure to not accidentally define an invented timer number that
actually collides with a proper 3GPP specified timer number that the author was
not aware of at the time of writing.
Add OSMO_T_FMT and OSMO_T_FMT_ARGS() macros as standardized timer number print
format. Use that in fsm.c, tdef_vty.c, and adjust vty tests accordingly.
Mention the two timer classes in various API docs and VTY online-docs.
Change-Id: I3a59457623da9309fbbda235fe18fadd1636bff6
Run INT_MAX and ULONG_MAX related tests only manually, remove from automatic
testing. This will hopefully fix recent build failures on various platforms.
Add a 64 bit output example for expected results when invoking
`./tdef_test range'. This is not checked automatically and merely serves for
manual reference.
For vty tests, use 32bit max values instead of INT_MAX and ULONG_MAX.
Change-Id: I6242243bde1d7ddebb858512a1f0b07f4ec3e5c2
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
Neels Hofmeyr