add osmo_fsm_inst_state_chg_keep_timer()

Change-Id: I3c0e53b846b2208bd201ace99777f2286ea39ae8

1 files changed, 64 insertions, 30 deletions

diff --git a/src/fsm.c b/src/fsm.c
index 0370f65e..b5af2e7a 100644
--- a/src/fsm.c
+++ b/src/fsm.c
@@ -429,33 +429,9 @@ const char *osmo_fsm_state_name(struct osmo_fsm *fsm, uint32_t state)
 		return fsm->states[state].name;
 }
 
-/*! perform a state change of the given FSM instance
- *
- *  Best invoke via the osmo_fsm_inst_state_chg() macro which logs the source
- *  file where the state change was effected. Alternatively, you may pass \a
- *  file as NULL to use the normal file/line indication instead.
- *
- *  All changes to the FSM instance state must be made via this
- *  function.  It verifies that the existing state actually permits a
- *  transiiton to new_state.
- *
- *  timeout_secs and T are optional parameters, and only have any effect
- *  if timeout_secs is not 0.  If the timeout function is used, then the
- *  new_state is entered, and the FSM instances timer is set to expire
- *  in timeout_secs functions.   At that time, the FSM's timer_cb
- *  function will be called for handling of the timeout by the user.
- *
- *  \param[in] fi FSM instance whose state is to change
- *  \param[in] new_state The new state into which we should change
- *  \param[in] timeout_secs Timeout in seconds (if !=0)
- *  \param[in] T Timer number (if \ref timeout_secs != 0)
- *  \param[in] file Calling source file (from osmo_fsm_inst_state_chg macro)
- *  \param[in] line Calling source line (from osmo_fsm_inst_state_chg macro)
- *  \returns 0 on success; negative on error
- */
-int _osmo_fsm_inst_state_chg(struct osmo_fsm_inst *fi, uint32_t new_state,
-			     unsigned long timeout_secs, int T,
-			     const char *file, int line)
+static int state_chg(struct osmo_fsm_inst *fi, uint32_t new_state,
+		     bool keep_timer, unsigned long timeout_secs, int T,
+		     const char *file, int line)
 {
 	struct osmo_fsm *fsm = fi->fsm;
 	uint32_t old_state = fi->state;
@@ -469,8 +445,10 @@ int _osmo_fsm_inst_state_chg(struct osmo_fsm_inst *fi, uint32_t new_state,
 		return -EPERM;
 	}
 
-	/* delete the old timer */
-	osmo_timer_del(&fi->timer);
+	if (!keep_timer) {
+		/* delete the old timer */
+		osmo_timer_del(&fi->timer);
+	}
 
 	if (st->onleave)
 		st->onleave(fi, new_state);
@@ -480,7 +458,7 @@ int _osmo_fsm_inst_state_chg(struct osmo_fsm_inst *fi, uint32_t new_state,
 	fi->state = new_state;
 	st = &fsm->states[new_state];
 
-	if (timeout_secs) {
+	if (!keep_timer && timeout_secs) {
 		fi->T = T;
 		osmo_timer_schedule(&fi->timer, timeout_secs, 0);
 	}
@@ -492,6 +470,62 @@ int _osmo_fsm_inst_state_chg(struct osmo_fsm_inst *fi, uint32_t new_state,
 	return 0;
 }
 
+/*! perform a state change of the given FSM instance
+ *
+ *  Best invoke via the osmo_fsm_inst_state_chg() macro which logs the source
+ *  file where the state change was effected. Alternatively, you may pass \a
+ *  file as NULL to use the normal file/line indication instead.
+ *
+ *  All changes to the FSM instance state must be made via an osmo_fsm_inst_state_chg_*
+ *  function.  It verifies that the existing state actually permits a
+ *  transition to new_state.
+ *
+ *  timeout_secs and T are optional parameters, and only have any effect
+ *  if timeout_secs is not 0.  If the timeout function is used, then the
+ *  new_state is entered, and the FSM instances timer is set to expire
+ *  in timeout_secs functions.   At that time, the FSM's timer_cb
+ *  function will be called for handling of the timeout by the user.
+ *
+ *  \param[in] fi FSM instance whose state is to change
+ *  \param[in] new_state The new state into which we should change
+ *  \param[in] timeout_secs Timeout in seconds (if !=0)
+ *  \param[in] T Timer number (if \ref timeout_secs != 0)
+ *  \param[in] file Calling source file (from osmo_fsm_inst_state_chg macro)
+ *  \param[in] line Calling source line (from osmo_fsm_inst_state_chg macro)
+ *  \returns 0 on success; negative on error
+ */
+int _osmo_fsm_inst_state_chg(struct osmo_fsm_inst *fi, uint32_t new_state,
+			     unsigned long timeout_secs, int T,
+			     const char *file, int line)
+{
+	return state_chg(fi, new_state, false, timeout_secs, T, file, line);
+}
+
+/*! perform a state change while keeping the current timer running.
+ *
+ *  This is useful to keep a timeout across several states (without having to round the
+ *  remaining time to seconds).
+ *
+ *  Best invoke via the osmo_fsm_inst_state_chg_keep_timer() macro which logs the source
+ *  file where the state change was effected. Alternatively, you may pass \a
+ *  file as NULL to use the normal file/line indication instead.
+ *
+ *  All changes to the FSM instance state must be made via an osmo_fsm_inst_state_chg_*
+ *  function.  It verifies that the existing state actually permits a
+ *  transition to new_state.
+ *
+ *  \param[in] fi FSM instance whose state is to change
+ *  \param[in] new_state The new state into which we should change
+ *  \param[in] file Calling source file (from osmo_fsm_inst_state_chg macro)
+ *  \param[in] line Calling source line (from osmo_fsm_inst_state_chg macro)
+ *  \returns 0 on success; negative on error
+ */
+int _osmo_fsm_inst_state_chg_keep_timer(struct osmo_fsm_inst *fi, uint32_t new_state,
+					const char *file, int line)
+{
+	return state_chg(fi, new_state, true, 0, 0, file, line);
+}
+
 /*! dispatch an event to an osmocom finite state machine instance
  *
  *  Best invoke via the osmo_fsm_inst_dispatch() macro which logs the source