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srsRAN_4G/lib/test/common/fsm_test.cc

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/*
* Copyright 2013-2020 Software Radio Systems Limited
*
* This file is part of srsLTE.
*
* srsLTE is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as
* published by the Free Software Foundation, either version 3 of
* the License, or (at your option) any later version.
*
* srsLTE is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* A copy of the GNU Affero General Public License can be found in
* the LICENSE file in the top-level directory of this distribution
* and at http://www.gnu.org/licenses/.
*
*/
#include "srslte/common/fsm.h"
#include "srslte/common/test_common.h"
/////////////////////////////
// Events
struct ev1 {};
struct ev2 {};
std::vector<std::string> calls;
template <typename State>
void call_log_helper(State* state, srslte::log_ref log_h, const char* type)
{
std::string callname = srslte::get_type_name<State>() + "::" + type;
log_h->info("%s custom called\n", callname.c_str());
calls.push_back(callname);
}
class fsm1 : public srslte::fsm_t<fsm1>
{
public:
uint32_t idle_enter_counter = 0, state1_enter_counter = 0, inner_enter_counter = 0;
uint32_t foo_counter = 0;
// states
struct idle_st {
void enter(fsm1* f);
};
struct state1 {
void enter(fsm1* f) {}
void enter(fsm1* f, const ev1& ev);
void enter(fsm1* f, const ev2& ev);
void exit(fsm1* f);
};
explicit fsm1(srslte::log_ref log_) : srslte::fsm_t<fsm1>(log_) {}
// this state is another FSM
class fsm2 : public subfsm_t<fsm2>
{
public:
// states
struct state_inner {
void enter(fsm2* f)
{
call_log_helper(this, f->get_log(), "enter");
f->parent_fsm()->inner_enter_counter++;
}
};
struct state_inner2 {
void enter(fsm2* f) { call_log_helper(this, f->get_log(), "enter"); }
void exit(fsm2* f) { call_log_helper(this, f->get_log(), "exit"); }
};
explicit fsm2(fsm1* f_) : composite_fsm_t(f_) {}
fsm2(fsm2&&) = default;
fsm2& operator=(fsm2&&) = default;
~fsm2() { get_log()->info("%s being destroyed!", get_type_name(*this).c_str()); }
void enter(fsm1* f) { call_log_helper(this, get_log(), "enter"); }
void exit(fsm1* f) { call_log_helper(this, get_log(), "exit"); }
private:
void inner_action1(state_inner& s, const ev1& e);
void inner_action2(state_inner& s, const ev2& e);
void inner_action3(state_inner2& s, const ev2& e);
protected:
// list of states
state_list<state_inner, state_inner2> states{this};
// clang-format off
using transitions = transition_table<
// Start Target Event Action
// +------------+-------------+----+----------------------+
upd<state_inner, ev1, &fsm2::inner_action1 >,
row<state_inner, state_inner2, ev2, &fsm2::inner_action2 >,
row<state_inner2, state1, ev2, &fsm2::inner_action3 >
// +------------+-------------+----+----------------------+
>;
// clang-format on
};
private:
void action1(idle_st& s, const ev1& e);
void action2(state1& s, const ev1& e);
void action3(state1& s, const ev2& e);
protected:
void foo(ev1 e) { foo_counter++; }
// list of states + transitions
state_list<idle_st, state1, fsm2> states = {this, idle_st{}, state1{}, fsm2{this}};
// clang-format off
using transitions = transition_table<
// Start Target Event Action
// +------------+-------------+----+------------------+
row< idle_st, state1, ev1, &fsm1::action1 >,
row< state1, fsm2, ev1, &fsm1::action2 >,
row< state1, idle_st, ev2, &fsm1::action3 >
// +------------+-------------+----+------------------+
>;
// clang-format on
};
void fsm1::idle_st::enter(fsm1* f)
{
call_log_helper(this, f->log_h, "enter");
f->idle_enter_counter++;
}
void fsm1::state1::enter(fsm1* f, const ev1& ev)
{
call_log_helper(this, f->log_h, "enter");
f->state1_enter_counter++;
}
void fsm1::state1::enter(fsm1* f, const ev2& ev)
{
call_log_helper(this, f->log_h, "enter2");
f->state1_enter_counter++;
}
void fsm1::state1::exit(fsm1* f)
{
call_log_helper(this, f->log_h, "exit");
}
// FSM event handlers
void fsm1::fsm2::inner_action1(state_inner& s, const ev1& e)
{
call_log_helper(this, get_log(), "inner_action1");
}
void fsm1::fsm2::inner_action2(state_inner& s, const ev2& e)
{
call_log_helper(this, get_log(), "inner_action2");
}
void fsm1::fsm2::inner_action3(state_inner2& s, const ev2& e)
{
get_log()->info("fsm2::state_inner2::react called\n");
}
void fsm1::action1(idle_st& s, const ev1& e)
{
call_log_helper(this, log_h, "action1");
foo(e);
}
void fsm1::action2(state1& s, const ev1& ev)
{
call_log_helper(this, log_h, "action2");
}
void fsm1::action3(state1& s, const ev2& ev)
{
call_log_helper(this, log_h, "action3");
}
// Static Checks
namespace srslte {
namespace fsm_details {
static_assert(is_fsm<fsm1>::value, "invalid metafunction\n");
static_assert(is_composite_fsm<fsm1::fsm2>::value, "invalid metafunction\n");
static_assert(type_list_size(typename filter_transition_type<ev1, fsm1::idle_st, fsm_transitions<fsm1> >::type{}) > 0,
"invalid filter metafunction\n");
static_assert(
std::is_same<fsm_state_list_type<fsm1>, fsm1::state_list<fsm1::idle_st, fsm1::state1, fsm1::fsm2> >::value,
"get state list failed\n");
static_assert(fsm1::can_hold_state<fsm1::state1>(), "failed can_hold_state check\n");
static_assert(std::is_same<enable_if_fsm_state<fsm1, fsm1::idle_st>, void>::value, "get state list failed\n");
static_assert(std::is_same<disable_if_fsm_state<fsm1, fsm1::fsm2::state_inner>, void>::value,
"get state list failed\n");
} // namespace fsm_details
} // namespace srslte
// Runtime checks
int test_hsm()
{
srslte::log_ref log_h{"HSM"};
log_h->set_level(srslte::LOG_LEVEL_INFO);
fsm1 f{log_h};
TESTASSERT(f.idle_enter_counter == 1);
TESTASSERT(get_type_name(f) == "fsm1");
TESTASSERT(f.current_state_name() == "idle_st");
TESTASSERT(f.is_in_state<fsm1::idle_st>());
TESTASSERT(f.foo_counter == 0);
// Moving Idle -> State1
ev1 e;
f.trigger(e);
TESTASSERT(f.current_state_name() == "state1");
TESTASSERT(f.is_in_state<fsm1::state1>());
// Moving State1 -> fsm2
f.trigger(e);
TESTASSERT(f.current_state_name() == "fsm2");
TESTASSERT(f.is_in_state<fsm1::fsm2>());
TESTASSERT(f.get_if_current_state<fsm1::fsm2>()->current_state_name() == "state_inner");
TESTASSERT(f.inner_enter_counter == 1);
// Fsm2 does not listen to ev1
f.trigger(e);
TESTASSERT(f.current_state_name() == "fsm2");
TESTASSERT(f.is_in_state<fsm1::fsm2>());
TESTASSERT(f.get_if_current_state<fsm1::fsm2>()->current_state_name() == "state_inner");
// Fsm2 state_inner -> state_inner2
f.trigger(ev2{});
TESTASSERT(f.current_state_name() == "fsm2");
TESTASSERT(f.is_in_state<fsm1::fsm2>());
TESTASSERT(f.get_if_current_state<fsm1::fsm2>()->current_state_name() == "state_inner2");
// Moving fsm2 -> state1
f.trigger(ev2{});
TESTASSERT(f.current_state_name() == "state1");
TESTASSERT(f.is_in_state<fsm1::state1>());
TESTASSERT(f.state1_enter_counter == 2);
// Moving state1 -> idle
f.trigger(ev2{});
TESTASSERT(std::string{f.current_state_name()} == "idle_st");
TESTASSERT(f.is_in_state<fsm1::idle_st>());
TESTASSERT(f.foo_counter == 1);
TESTASSERT(f.idle_enter_counter == 2);
// Call unhandled event
f.trigger(ev2{});
TESTASSERT(f.current_state_name() == "idle_st");
// Enter fsm2 again
f.trigger(ev1{});
f.trigger(ev1{});
TESTASSERT(f.current_state_name() == "fsm2");
TESTASSERT(f.is_in_state<fsm1::fsm2>());
TESTASSERT(f.get_if_current_state<fsm1::fsm2>()->current_state_name() == "state_inner");
// Ensure correct call order
TESTASSERT(calls[0] == srslte::get_type_name<fsm1::idle_st>() + "::enter"); // enter for init state called
TESTASSERT(calls[1] == srslte::get_type_name<fsm1>() + "::action1");
TESTASSERT(calls[2] == srslte::get_type_name<fsm1::state1>() + "::enter");
TESTASSERT(calls[3] == srslte::get_type_name<fsm1>() + "::action2");
TESTASSERT(calls[4] == srslte::get_type_name<fsm1::state1>() + "::exit");
TESTASSERT(calls[5] == srslte::get_type_name<fsm1::fsm2>() + "::enter"); // entry is recursive
TESTASSERT(calls[6] == srslte::get_type_name<fsm1::fsm2::state_inner>() + "::enter");
TESTASSERT(calls[7] == srslte::get_type_name<fsm1::fsm2>() + "::inner_action1");
TESTASSERT(calls[8] == srslte::get_type_name<fsm1::fsm2>() + "::inner_action2");
TESTASSERT(calls[9] == srslte::get_type_name<fsm1::fsm2::state_inner2>() + "::enter");
TESTASSERT(calls[10] == srslte::get_type_name<fsm1::fsm2::state_inner2>() + "::exit");
TESTASSERT(calls[11] == srslte::get_type_name<fsm1::fsm2>() + "::exit"); // exit is recursive
TESTASSERT(calls[12] == srslte::get_type_name<fsm1::state1>() + "::enter2"); // differentiates different entry funcs
return SRSLTE_SUCCESS;
}
/////////////////////////////
struct procevent1 {
bool is_success;
};
struct proc1 : public srslte::proc_fsm_t<proc1, int> {
public:
struct procstate1 {
void enter(proc1* f, const srslte::proc_launch_ev<int>& ev);
};
explicit proc1(srslte::log_ref log_) : base_t(log_) {}
protected:
// Transitions
void handle_success(procstate1& s, const procevent1& ev);
void handle_failure(procstate1& s, const procevent1& ev);
bool is_success(procstate1& s, const procevent1& ev) { return ev.is_success; }
bool is_failure(procstate1& s, const procevent1& ev) { return not ev.is_success; }
state_list<idle_st, procstate1> states{this, idle_st{}, procstate1{}};
// clang-format off
using transitions = transition_table<
// Start Target Event Action Guard (optional)
// +------------+-------------+----------------+------------------------+--------------------+
row< idle_st, procstate1, launch_ev<int> >,
upd< procstate1, procevent1, &proc1::handle_success, &proc1::is_success >,
upd< procstate1, procevent1, &proc1::handle_failure, &proc1::is_failure >,
to_state< idle_st, complete_ev >
// +------------+-------------+----------------+------------------------+--------------------+
>;
// clang-format on
};
void proc1::procstate1::enter(proc1* f, const launch_ev<int>& ev)
{
f->log_h->info("started!\n");
}
void proc1::handle_success(procstate1& s, const procevent1& ev)
{
log_h->info("success!\n");
trigger(complete_ev{5});
}
void proc1::handle_failure(procstate1& s, const procevent1& ev)
{
log_h->info("failure!\n");
trigger(complete_ev{3});
}
struct proc_listener_fsm : public srslte::fsm_t<proc_listener_fsm> {
public:
struct st1 {};
struct st2 {};
using proc1_st = srslte::proc_wait_st<proc1>;
explicit proc_listener_fsm(srslte::log_ref log_, proc1* proc_ptr_) :
base_t(log_),
states(this, st1{}, st2{}, proc1_st{proc_ptr_})
{}
protected:
bool is_success(proc1_st& s, const proc1::complete_ev& ev) { return ev.result; }
// clang-format off
state_list<st1, st2, proc1_st > states;
using f = proc_listener_fsm;
using transitions = transition_table<
// Start Target Event Action Guard (optional)
// +--------------+--------------+-----------------------+------------------------+-------------------+
row< st1, proc1_st, int >,
row< proc1_st, st2, proc1::complete_ev, nullptr, &f::is_success >,
row< proc1_st, st1, proc1::complete_ev >
// +--------------+--------------+-----------------------+------------------------+-------------------+
>;
// clang-format on
};
int test_fsm_proc()
{
proc1 proc{srslte::logmap::get("PROC")};
proc.get_log()->set_level(srslte::LOG_LEVEL_INFO);
proc.set_fsm_event_log_level(srslte::LOG_LEVEL_INFO);
int v = 2;
TESTASSERT(proc.current_state_name() == "idle_st");
proc.trigger(srslte::proc_launch_ev<int>{v});
TESTASSERT(proc.current_state_name() == "procstate1");
proc.trigger(srslte::proc_launch_ev<int>{v});
TESTASSERT(proc.current_state_name() == "procstate1");
proc.trigger(srslte::proc_launch_ev<int>{5});
TESTASSERT(proc.current_state_name() == "procstate1");
proc.trigger(procevent1{true});
TESTASSERT(proc.current_state_name() == "idle_st");
TESTASSERT(proc.get_result() == 5);
proc.trigger(srslte::proc_launch_ev<int>{v});
TESTASSERT(proc.current_state_name() == "procstate1");
proc.trigger(procevent1{false});
TESTASSERT(proc.current_state_name() == "idle_st");
TESTASSERT(proc.get_result() == 3);
{
proc_listener_fsm outer_fsm{srslte::logmap::get("TEST"), &proc};
TESTASSERT(outer_fsm.is_in_state<proc_listener_fsm::st1>());
outer_fsm.trigger(6);
TESTASSERT(outer_fsm.is_in_state<proc_listener_fsm::proc1_st>());
TESTASSERT(proc.is_running());
proc.trigger(procevent1{true});
TESTASSERT(not proc.is_running());
TESTASSERT(outer_fsm.is_in_state<proc_listener_fsm::st2>());
}
{
proc_listener_fsm outer_fsm{srslte::logmap::get("TEST"), &proc};
TESTASSERT(outer_fsm.is_in_state<proc_listener_fsm::st1>());
proc.trigger(srslte::proc_launch_ev<int>{v});
TESTASSERT(proc.is_running());
outer_fsm.trigger(7);
TESTASSERT(outer_fsm.is_in_state<proc_listener_fsm::st1>());
TESTASSERT(proc.is_running());
}
return SRSLTE_SUCCESS;
}
///////////////////////////
class nas_fsm : public srslte::fsm_t<nas_fsm>
{
public:
// states
struct emm_null_st {};
struct emm_deregistered {};
struct emm_deregistered_initiated {};
struct emm_ta_updating_initiated {};
struct emm_registered {};
struct emm_service_req_initiated {};
struct emm_registered_initiated {};
// events
struct enable_s1_ev {};
struct disable_s1_ev {};
struct attach_request_ev {};
struct emm_registr_fail_ev {}; ///< attach rejected, network init DETACH request, lower layer failure
struct attach_accept_ev {}; ///< attach accept and default EPS bearer context activated
struct sr_initiated_ev {};
struct sr_outcome_ev {};
struct tau_request_ev {};
struct tau_outcome_ev {};
struct tau_reject_other_cause_ev {};
struct power_off_ev {};
struct detach_request_ev {};
struct detach_accept_ev {};
nas_fsm(srslte::log_ref log_) : fsm_t<nas_fsm>(log_) {}
protected:
state_list<emm_null_st,
emm_deregistered,
emm_registered_initiated,
emm_registered,
emm_service_req_initiated,
emm_ta_updating_initiated,
emm_deregistered_initiated>
states{nullptr};
// clang-format off
using transitions = transition_table<
// Start Target Event
// +-----------------------------+-------------------------+-----------------------------+
row< emm_null_st, emm_deregistered, enable_s1_ev >,
row< emm_deregistered, emm_null_st, disable_s1_ev >,
row< emm_deregistered, emm_registered_initiated, attach_request_ev >,
row< emm_registered_initiated, emm_deregistered, emm_registr_fail_ev >,
row< emm_registered_initiated, emm_registered, attach_accept_ev >,
row< emm_registered, emm_service_req_initiated, sr_initiated_ev >,
row< emm_service_req_initiated, emm_registered, sr_outcome_ev >,
row< emm_registered, emm_ta_updating_initiated, tau_request_ev >,
row< emm_registered, emm_deregistered_initiated, detach_request_ev >,
row< emm_ta_updating_initiated, emm_registered, tau_outcome_ev >,
row< emm_ta_updating_initiated, emm_deregistered, tau_reject_other_cause_ev >,
row< emm_deregistered_initiated, emm_deregistered, detach_accept_ev >,
to_state< emm_deregistered, power_off_ev >
// +-----------------------------+-------------------------+-----------------------------+
>;
// clang-format on
};
int test_nas_fsm()
{
srslte::log_ref log_h{"NAS"};
log_h->set_level(srslte::LOG_LEVEL_INFO);
nas_fsm fsm{log_h};
TESTASSERT(fsm.is_in_state<nas_fsm::emm_null_st>());
// NULL -> EMM-DEREGISTERED
fsm.trigger(nas_fsm::enable_s1_ev{});
TESTASSERT(fsm.is_in_state<nas_fsm::emm_deregistered>());
// EMM-DEREGISTERED -> EMM-NULL -> EMM-DEREGISTERED
fsm.trigger(nas_fsm::disable_s1_ev{});
TESTASSERT(fsm.is_in_state<nas_fsm::emm_null_st>());
fsm.trigger(nas_fsm::enable_s1_ev{});
TESTASSERT(fsm.is_in_state<nas_fsm::emm_deregistered>());
// EMM-DEREGISTERED -> EMM-REGISTERED-INITIATED -> EMM-DEREGISTERED
fsm.trigger(nas_fsm::attach_request_ev{});
TESTASSERT(fsm.is_in_state<nas_fsm::emm_registered_initiated>());
fsm.trigger(nas_fsm::emm_registr_fail_ev{});
TESTASSERT(fsm.is_in_state<nas_fsm::emm_deregistered>());
// EMM-DEREGISTERED -> EMM-REGISTERED-INITIATED -> EMM-REGISTERED
fsm.trigger(nas_fsm::attach_request_ev{});
TESTASSERT(fsm.is_in_state<nas_fsm::emm_registered_initiated>());
fsm.trigger(nas_fsm::attach_accept_ev{});
TESTASSERT(fsm.is_in_state<nas_fsm::emm_registered>());
// EMM-REGISTERED -> EMM-SERVICE-REQUEST-INITIATED -> EMM-REGISTERED
fsm.trigger(nas_fsm::sr_initiated_ev{});
TESTASSERT(fsm.is_in_state<nas_fsm::emm_service_req_initiated>());
fsm.trigger(nas_fsm::sr_outcome_ev{});
TESTASSERT(fsm.is_in_state<nas_fsm::emm_registered>());
// EMM-REGISTERED -> EMM-TRACKING-AREA-UPDATING-INITIATED -> EMM-REGISTERED
fsm.trigger(nas_fsm::tau_request_ev{});
TESTASSERT(fsm.is_in_state<nas_fsm::emm_ta_updating_initiated>());
fsm.trigger(nas_fsm::tau_outcome_ev{});
TESTASSERT(fsm.is_in_state<nas_fsm::emm_registered>());
// EMM-REGISTERED -> EMM-DEREGISTED-INITIATED -> EMM-DEREGISTERED
fsm.trigger(nas_fsm::detach_request_ev{});
TESTASSERT(fsm.is_in_state<nas_fsm::emm_deregistered_initiated>());
fsm.trigger(nas_fsm::detach_accept_ev{});
TESTASSERT(fsm.is_in_state<nas_fsm::emm_deregistered>());
// EMM-DEREGISTERED -> EMM-REGISTERED-INITIATED -> EMM-REGISTERED -> EMM-TRACKING-AREA-UPDATING-INITIATED ->
// EMM-DEREGISTERED
fsm.trigger(nas_fsm::attach_request_ev{});
TESTASSERT(fsm.is_in_state<nas_fsm::emm_registered_initiated>());
fsm.trigger(nas_fsm::attach_accept_ev{});
TESTASSERT(fsm.is_in_state<nas_fsm::emm_registered>());
fsm.trigger(nas_fsm::tau_request_ev{});
fsm.trigger(nas_fsm::tau_reject_other_cause_ev{});
TESTASSERT(fsm.is_in_state<nas_fsm::emm_deregistered>());
// EMM-DEREGISTERED -> EMM-REGISTERED-INITIATED -> EMM-REGISTERED -> EMM-SERVICE-REQUEST-INITIATED -> EMM-DEREGISTERED
// (power-off)
fsm.trigger(nas_fsm::attach_request_ev{});
fsm.trigger(nas_fsm::attach_accept_ev{});
fsm.trigger(nas_fsm::sr_initiated_ev{});
TESTASSERT(fsm.is_in_state<nas_fsm::emm_service_req_initiated>());
fsm.trigger(nas_fsm::power_off_ev{});
TESTASSERT(fsm.is_in_state<nas_fsm::emm_deregistered>());
return SRSLTE_SUCCESS;
}
struct fsm3 : public srslte::fsm_t<fsm3> {
struct st1 {};
struct st2 {
int counter = 0;
void enter(fsm3* fsm)
{
counter++;
fsm->events.push_back(fsm->current_state_name());
}
};
fsm3() : base_t(srslte::log_ref{"TEST"}) {}
std::vector<std::string> events;
protected:
void handle_ev1(st1& s, const ev1& ev)
{
trigger(ev2{});
events.push_back(current_state_name() + "::action"); // still in st1
}
void handle_ev2(st2& s, const ev2& ev)
{
if (s.counter < 2) {
trigger(ev1{});
}
events.push_back(current_state_name() + "::action"); // still in st2
}
state_list<st1, st2> states{this};
// clang-format off
using transitions = transition_table<
// Start Target Event Action
// +------------------------+-------------------------+-------------------+--------------------+
row< st1, st2, ev1, &fsm3::handle_ev1 >,
row< st2, st1, ev2, &fsm3::handle_ev2 >
// +------------------------+-------------------------+-------------------+--------------------+
>;
// clang-format on
};
int test_fsm_self_trigger()
{
fsm3 fsm;
TESTASSERT(fsm.events.empty());
TESTASSERT(fsm.is_in_state<fsm3::st1>());
fsm.trigger(ev1{});
TESTASSERT(fsm.is_in_state<fsm3::st1>());
TESTASSERT(fsm.events.size() == 6);
TESTASSERT(fsm.events[0] == "st1::action");
TESTASSERT(fsm.events[1] == "st2");
TESTASSERT(fsm.events[2] == "st2::action");
TESTASSERT(fsm.events[3] == "st1::action");
TESTASSERT(fsm.events[4] == "st2");
TESTASSERT(fsm.events[5] == "st2::action");
return SRSLTE_SUCCESS;
}
int main()
{
srslte::log_ref testlog{"TEST"};
testlog->set_level(srslte::LOG_LEVEL_INFO);
TESTASSERT(test_hsm() == SRSLTE_SUCCESS);
testlog->info("TEST \"hsm\" finished successfully\n\n");
TESTASSERT(test_fsm_proc() == SRSLTE_SUCCESS);
testlog->info("TEST \"proc\" finished successfully\n\n");
TESTASSERT(test_nas_fsm() == SRSLTE_SUCCESS);
testlog->info("TEST \"nas fsm\" finished successfully\n\n");
TESTASSERT(test_fsm_self_trigger() == SRSLTE_SUCCESS);
testlog->info("TEST \"fsm self trigger\" finished successfully\n\n");
return SRSLTE_SUCCESS;
}
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