Change in libosmocore[master]: fsm: add osmo_fsm_inst_state_chg_keep_or_start_timer()

Neels Hofmeyr gerrit-no-reply at
Fri Mar 8 04:13:39 UTC 2019

Hello Harald Welte, Jenkins Builder, 

I'd like you to reexamine a change. Please visit

to look at the new patch set (#2).

Change subject: fsm: add osmo_fsm_inst_state_chg_keep_or_start_timer()

fsm: add osmo_fsm_inst_state_chg_keep_or_start_timer()

During FSM design for osmo-msc, I noticed that the current behavior that
keep_timer=true doesn't guarantee a running timer can make FSM design a bit
complex, especially when using osmo_tdef for timeout definitions.

A desirable keep_timer=true behavior is one that keeps the previous timer
running, but starts a timer if no timer is running yet.

The simplest example is: a given state repeatedly transitions back to itself,
but wants to set a timeout only on first entering, avoiding to restart the
timeout on re-entering.

Another example is a repeated transition between two or more states, where the
first time we enter this group a timeout should start, but it should not
restart from scratch on every transition.

When using osmo_tdef timeout definitions for this, so far separate meaningless
states have to be introduced that merely set a fixed timeout.

To simplify, add osmo_fsm_inst_state_chg_keep_or_start_timer(), and use this in
osmo_tdef_fsm_inst_state_chg() when both keep_timer == true *and* T != 0.

In tdef_test.ok, the changes show that on first entering state L, the previous
T=1 is now kept with a large remaining timeout. When entering state L from O,
where no timer was running, this time L's T123 is started.

Change-Id: Id647511a4b18e0c4de0e66fb1f35dc9adb9177db
M include/osmocom/core/fsm.h
M src/fsm.c
M src/tdef.c
M tests/tdef/tdef_test.ok
M tests/tdef/tdef_test_range_64bit.ok
5 files changed, 76 insertions(+), 17 deletions(-)

  git pull ssh:// refs/changes/43/13143/2
To view, visit
To unsubscribe, or for help writing mail filters, visit

Gerrit-Project: libosmocore
Gerrit-Branch: master
Gerrit-MessageType: newpatchset
Gerrit-Change-Id: Id647511a4b18e0c4de0e66fb1f35dc9adb9177db
Gerrit-Change-Number: 13143
Gerrit-PatchSet: 2
Gerrit-Owner: Neels Hofmeyr <nhofmeyr at>
Gerrit-Reviewer: Harald Welte <laforge at>
Gerrit-Reviewer: Jenkins Builder (1000002)
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <>

More information about the gerrit-log mailing list