different way to retrieve a proc future

lib/include/srslte/common/stack_procedure.h

@@ -30,7 +30,7 @@
 
 namespace srslte {
 
-enum class proc_outcome_t { repeat, yield, success, error };
+enum class proc_outcome_t { yield, success, error };
 
 /**************************************************************************************
  * helper functions for method optional overloading
@@ -184,11 +184,12 @@ class proc_future_t
 public:
   proc_future_t() = default;
   explicit proc_future_t(const std::shared_ptr<proc_result_t<ResultType> >& p_) : ptr(p_) {}
-  bool              is_error() const { return ptr->is_error(); }
-  bool              is_success() const { return ptr->is_success(); }
-  bool              is_complete() const { return ptr->is_complete(); }
+  bool              is_error() const { return not is_empty() and ptr->is_error(); }
+  bool              is_success() const { return not is_empty() and ptr->is_success(); }
+  bool              is_complete() const { return not is_empty() and ptr->is_complete(); }
   const ResultType* value() const { return is_success() ? ptr->value() : nullptr; }
-  bool              is_valid() const { return ptr != nullptr; }
+  bool              is_empty() const { return ptr == nullptr; }
+  void              clear() { ptr->clear(); }
 
 private:
   std::shared_ptr<proc_result_t<ResultType> > ptr;
@@ -210,8 +211,6 @@ using proc_future_state_t = proc_future_t<void>;
  *            executes a procedure "action" based on its current internal state,
  *            and return a proc_outcome_t variable with possible values:
  *            - yield - the procedure performed the action but hasn't completed yet.
- *            - repeat - the same as yield, but explicitly asking that run() should
- *            recall step() again (probably the procedure state has changed)
  *            - error - the procedure has finished unsuccessfully
  *            - success - the procedure has completed successfully
  ************************************************************************************/
@@ -223,9 +222,8 @@ public:
   //! common proc::run() interface. Returns true if procedure is still running
   bool run()
   {
-    proc_outcome_t outcome = proc_outcome_t::repeat;
-    while (is_busy() and outcome == proc_outcome_t::repeat) {
-      outcome = step();
+    if (is_busy()) {
+      proc_outcome_t outcome = step();
       handle_outcome(outcome);
     }
     return is_busy();
@@ -292,20 +290,21 @@ public:
 
   //! method to handle external events. "T" must have the method "T::react(const Event&)" for the trigger to take effect
   template <class Event>
-  void trigger(Event&& e)
+  bool trigger(Event&& e)
   {
     if (is_busy()) {
       proc_outcome_t outcome = proc_ptr->react(std::forward<Event>(e));
       handle_outcome(outcome);
-      if (outcome == proc_outcome_t::repeat) {
-        run();
-      }
     }
+    return is_busy();
   }
 
   //! returns an object which the user can use to check if the procedure has ended.
   proc_future_type get_future()
   {
+    if (is_idle()) {
+      return proc_future_type{};
+    }
     if (future_result == nullptr) {
       future_result = std::make_shared<proc_result_type>();
     }
@@ -326,16 +325,22 @@ public:
     proc_state              = proc_base_t::proc_status_t::on_going;
     proc_outcome_t init_ret = proc_ptr->init(std::forward<Args>(args)...);
     handle_outcome(init_ret);
-    switch (init_ret) {
-      case proc_outcome_t::error:
-        return false;
-      case proc_outcome_t::repeat:
-        run(); // call run right away
-        break;
-      default:
-        break;
+    return init_ret != proc_outcome_t::error;
   }
-    return true;
+
+  //! launch a procedure, returning a future where the result is going to be saved
+  template <class... Args>
+  bool launch(proc_future_type* fut, Args&&... args)
+  {
+    if (is_busy()) {
+      fut->clear();
+      return fut;
+    }
+    proc_state              = proc_base_t::proc_status_t::on_going;
+    *fut                    = get_future();
+    proc_outcome_t init_ret = proc_ptr->init(std::forward<Args>(args)...);
+    handle_outcome(init_ret);
+    return init_ret != proc_outcome_t::error;
   }
 
 protected:

lib/test/common/stack_procedure_test.cc

@@ -216,7 +216,7 @@ static_assert(std::is_same<typename srslte::proc_t<custom_proc, std::string>::re
 int test_local_1()
 {
   /*
-   * Description: Test if a procedure is cleaned automatically after is lifetime has ended
+   * Description: Test if a procedure is cleaned automatically after its lifetime has ended
    */
   new_test();
   printf("\n--- Test %s ---\n", __func__);
@@ -297,8 +297,9 @@ int test_callback_2()
   srslte::proc_t<custom_proc, int> proc;
   TESTASSERT(not proc.is_busy());
   srslte::proc_future_t<int> fut = proc.get_future();
+  TESTASSERT(fut.is_empty());
 
-  TESTASSERT(proc.launch(3));
+  TESTASSERT(proc.launch(&fut, 3));
   TESTASSERT(proc.is_busy());
   callbacks.add_proc(std::move(proc));
   TESTASSERT(callbacks.size() == 1);
@@ -391,8 +392,8 @@ int test_complete_callback_1()
       TESTASSERT(proc.then_always(continuation_task) == 0)
     }
 
-    srslte::proc_future_t<std::string> fut = proc.get_future();
-    TESTASSERT(proc.launch());
+    srslte::proc_future_t<std::string> fut;
+    TESTASSERT(proc.launch(&fut));
     TESTASSERT(proc.get()->exit_val == "init")
     while (proc.run()) {
       TESTASSERT(proc.get()->exit_val == "init")

srsue/src/stack/rrc/rrc_procedures.cc

@@ -91,14 +91,13 @@ proc_outcome_t rrc::cell_search_proc::handle_cell_found(const phy_interface_rrc_
   }
 
   Info("Cell has no SIB1. Obtaining SIB1...\n");
-  si_acquire_fut = rrc_ptr->si_acquirer.get_future();
-  if (not rrc_ptr->si_acquirer.launch(0)) {
+  if (not rrc_ptr->si_acquirer.launch(&si_acquire_fut, 0)) {
     // disallow concurrent si_acquire
     Error("SI Acquire is already running...\n");
     return proc_outcome_t::error;
   }
   state = state_t::si_acquire;
-  return proc_outcome_t::repeat;
+  return step();
 }
 
 proc_outcome_t rrc::cell_search_proc::react(const cell_search_event_t& event)
@@ -178,7 +177,7 @@ proc_outcome_t rrc::si_acquire_proc::init(uint32_t sib_index_)
     }
   }
 
-  return proc_outcome_t::repeat;
+  return step();
 }
 
 proc_outcome_t rrc::si_acquire_proc::step()
@@ -261,7 +260,7 @@ proc_outcome_t rrc::serving_cell_config_proc::init(const std::vector<uint32_t>&
 
   req_idx      = 0;
   search_state = search_state_t::next_sib;
-  return proc_outcome_t::repeat;
+  return step();
 }
 
 proc_outcome_t rrc::serving_cell_config_proc::step()
@@ -273,13 +272,12 @@ proc_outcome_t rrc::serving_cell_config_proc::step()
 
       if (not rrc_ptr->serving_cell->has_sib(required_sib)) {
         Info("Cell has no SIB%d. Obtaining SIB%d\n", required_sib + 1, required_sib + 1);
-        si_acquire_fut = rrc_ptr->si_acquirer.get_future();
-        if (not rrc_ptr->si_acquirer.launch(required_sib)) {
+        if (not rrc_ptr->si_acquirer.launch(&si_acquire_fut, required_sib)) {
           Error("SI Acquire is already running...\n");
           return proc_outcome_t::error;
         }
         search_state = search_state_t::si_acquire;
-        return proc_outcome_t::repeat;
+        return step();
       } else {
         // UE had SIB already. Handle its SIB
         Info("Cell has SIB%d\n", required_sib + 1);
@@ -313,7 +311,7 @@ proc_outcome_t rrc::serving_cell_config_proc::step()
     // continue with remaining SIBs
     search_state = search_state_t::next_sib;
     req_idx++;
-    return proc_outcome_t::repeat;
+    return step();
   }
   return proc_outcome_t::yield;
 }
@@ -342,7 +340,7 @@ proc_outcome_t rrc::cell_selection_proc::init()
   neigh_index = 0;
   cs_result   = cs_result_t::no_cell;
   state       = search_state_t::cell_selection;
-  return proc_outcome_t::repeat;
+  return step();
 }
 
 proc_outcome_t rrc::cell_selection_proc::step_cell_selection()
@@ -366,7 +364,7 @@ proc_outcome_t rrc::cell_selection_proc::step_cell_selection()
       if (rrc_ptr->phy->cell_select(&rrc_ptr->serving_cell->phy_cell)) {
         Info("Wait PHY to be in-synch\n");
         state = search_state_t::wait_in_sync;
-        return proc_outcome_t::repeat;
+        return step();
       } else {
         rrc_ptr->phy_sync_state = phy_unknown_sync;
         Error("Could not camp on serving cell.\n");
@@ -393,20 +391,18 @@ proc_outcome_t rrc::cell_selection_proc::step_cell_selection()
 
   // If can not find any suitable cell, search again
   Info("Cell selection and reselection in IDLE did not find any suitable cell. Searching again\n");
-  cell_search_fut = rrc_ptr->cell_searcher.get_future();
-  if (not rrc_ptr->cell_searcher.launch()) {
+  if (not rrc_ptr->cell_searcher.launch(&cell_search_fut)) {
     return proc_outcome_t::error;
   }
   state = search_state_t::cell_search;
-  return proc_outcome_t::repeat;
+  return step();
 }
 
 proc_outcome_t rrc::cell_selection_proc::step_wait_in_sync()
 {
   if (rrc_ptr->phy_sync_state == phy_in_sync) {
     Info("PHY is in SYNC\n");
-    serv_cell_cfg_fut = rrc_ptr->serv_cell_cfg.get_future();
-    if (not rrc_ptr->serv_cell_cfg.launch(rrc_ptr->ue_required_sibs)) {
+    if (not rrc_ptr->serv_cell_cfg.launch(&serv_cell_cfg_fut, rrc_ptr->ue_required_sibs)) {
       return proc_outcome_t::error;
     }
     state = search_state_t::cell_config;
@@ -444,7 +440,7 @@ proc_outcome_t rrc::cell_selection_proc::step_cell_config()
   // resume cell selection
   state = search_state_t::cell_selection;
   ++neigh_index;
-  return proc_outcome_t::repeat;
+  return step();
 }
 
 proc_outcome_t rrc::cell_selection_proc::step()
@@ -481,12 +477,11 @@ proc_outcome_t rrc::plmn_search_proc::init()
 {
   Info("Starting PLMN search\n");
   nof_plmns = 0;
-  cell_search_fut = rrc_ptr->cell_searcher.get_future();
-  if (not rrc_ptr->cell_searcher.launch()) {
+  if (not rrc_ptr->cell_searcher.launch(&cell_search_fut)) {
     Error("Failed due to fail to init cell search...\n");
     return proc_outcome_t::error;
   }
-  return proc_outcome_t::repeat;
+  return step();
 }
 
 /* NAS interface to search for available PLMNs.
@@ -529,14 +524,13 @@ proc_outcome_t rrc::plmn_search_proc::step()
     return proc_outcome_t::success;
   }
 
-  cell_search_fut = rrc_ptr->cell_searcher.get_future();
-  if (not rrc_ptr->cell_searcher.launch()) {
+  if (not rrc_ptr->cell_searcher.launch(&cell_search_fut)) {
     Error("Failed due to fail to init cell search...\n");
     return proc_outcome_t::error;
   }
 
   // run again
-  return proc_outcome_t::repeat;
+  return step();
 }
 
 void rrc::plmn_search_proc::then(const srslte::proc_state_t& result) const
@@ -624,7 +618,7 @@ proc_outcome_t rrc::connection_request_proc::step()
     Info("Waiting for RRCConnectionSetup/Reject or expiry\n");
     rrc_ptr->dedicated_info_nas = std::move(dedicated_info_nas);
     state                       = state_t::wait_t300;
-    return proc_outcome_t::repeat;
+    return step();
 
   } else if (state == state_t::wait_t300) {
     // Wait until t300 stops due to RRCConnectionSetup/Reject or expiry
@@ -684,13 +678,12 @@ srslte::proc_outcome_t rrc::connection_request_proc::react(const cell_selection_
     // timeAlignmentCommon applied in configure_serving_cell
 
     Info("Configuring serving cell...\n");
-    serv_cfg_fut = rrc_ptr->serv_cell_cfg.get_future();
-    if (not rrc_ptr->serv_cell_cfg.launch(rrc_ptr->ue_required_sibs)) {
+    if (not rrc_ptr->serv_cell_cfg.launch(&serv_cfg_fut, rrc_ptr->ue_required_sibs)) {
       Error("Attach request failed to configure serving cell...\n");
       return proc_outcome_t::error;
     }
     state = state_t::config_serving_cell;
-    return proc_outcome_t::repeat;
+    return step();
   } else {
     switch (cs_ret) {
       case cs_result_t::same_cell:
@@ -721,7 +714,7 @@ proc_outcome_t rrc::process_pcch_proc::init(const asn1::rrc::paging_s& paging_)
   paging_idx = 0;
   state      = state_t::next_record;
   Info("starting...\n");
-  return proc_outcome_t::repeat;
+  return step();
 }
 
 proc_outcome_t rrc::process_pcch_proc::step()
@@ -743,7 +736,7 @@ proc_outcome_t rrc::process_pcch_proc::step()
             return proc_outcome_t::error;
           }
           state = state_t::nas_paging;
-          return proc_outcome_t::repeat;
+          return step();
         } else {
           Warning("Received paging while in CONNECT\n");
         }
@@ -757,8 +750,7 @@ proc_outcome_t rrc::process_pcch_proc::step()
       rrc_ptr->serving_cell->reset_sibs();
 
       // create a serving cell config procedure and push it to callback list
-      serv_cfg_fut = rrc_ptr->serv_cell_cfg.get_future();
-      if (not rrc_ptr->serv_cell_cfg.launch(rrc_ptr->ue_required_sibs)) {
+      if (not rrc_ptr->serv_cell_cfg.launch(&serv_cfg_fut, rrc_ptr->ue_required_sibs)) {
         Error("Failed to initiate a serving cell configuration procedure\n");
         return proc_outcome_t::error;
       }
@@ -767,7 +759,7 @@ proc_outcome_t rrc::process_pcch_proc::step()
       return proc_outcome_t::success;
     }
     state = state_t::serv_cell_cfg;
-    return proc_outcome_t::repeat;
+    return step();
   } else if (state == state_t::nas_paging) {
     // wait for trigger
     return proc_outcome_t::yield;
@@ -799,7 +791,7 @@ proc_outcome_t rrc::process_pcch_proc::react(paging_complete e)
   paging_idx++;
   state = state_t::next_record;
   Info("Received paging complete event\n");
-  return proc_outcome_t::repeat;
+  return step();
 }
 
 /**************************************
@@ -841,8 +833,7 @@ rrc::cell_reselection_proc::cell_reselection_proc(srsue::rrc* rrc_) : rrc_ptr(rr
 proc_outcome_t rrc::cell_reselection_proc::init()
 {
   Info("Starting...\n");
-  cell_selection_fut = rrc_ptr->cell_selector.get_future();
-  if (not rrc_ptr->cell_selector.launch()) {
+  if (not rrc_ptr->cell_selector.launch(&cell_selection_fut)) {
     Error("Failed to initiate a Cell Selection procedure...\n");
     return proc_outcome_t::error;
   }

srsue/src/stack/upper/nas.cc

@@ -213,7 +213,7 @@ proc_outcome_t nas::rrc_connect_proc::react(nas::rrc_connect_proc::connection_re
     // Wait until attachment. If doing a service request is already attached
     state = state_t::wait_attach;
     // wake up proc
-    return proc_outcome_t::repeat;
+    return step();
   } else {
     ProcError("Could not establish RRC connection\n");
     return proc_outcome_t::error;