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Diffstat (limited to 'ucs2-lib/src/ucs_fsm.c')
| -rw-r--r-- | ucs2-lib/src/ucs_fsm.c | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/ucs2-lib/src/ucs_fsm.c b/ucs2-lib/src/ucs_fsm.c new file mode 100644 index 0000000..c180b0a --- /dev/null +++ b/ucs2-lib/src/ucs_fsm.c @@ -0,0 +1,172 @@ +/*------------------------------------------------------------------------------------------------*/ +/* UNICENS V2.1.0-3491 */ +/* Copyright (c) 2017 Microchip Technology Germany II GmbH & Co. KG. */ +/* */ +/* This program is free software: you can redistribute it and/or modify */ +/* it under the terms of the GNU General Public License as published by */ +/* the Free Software Foundation, either version 2 of the License, or */ +/* (at your option) any later version. */ +/* */ +/* This program 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 General Public License for more details. */ +/* */ +/* You should have received a copy of the GNU General Public License */ +/* along with this program. If not, see <http://www.gnu.org/licenses/>. */ +/* */ +/* You may also obtain this software under a propriety license from Microchip. */ +/* Please contact Microchip for further information. */ +/*------------------------------------------------------------------------------------------------*/ + +/*! + * \file + * \brief Implementation of the Finite State Machine. + * + * \cond UCS_INTERNAL_DOC + * \addtogroup G_FSM + * @{ + */ + +/*------------------------------------------------------------------------------------------------*/ +/* Includes */ +/*------------------------------------------------------------------------------------------------*/ +#include "ucs_fsm.h" +#include "ucs_misc.h" + +/*------------------------------------------------------------------------------------------------*/ +/* Internal definitions */ +/*------------------------------------------------------------------------------------------------*/ +/*! \brief NIL-event, indicates that no event is pending at the moment */ +#define FSM_E_NILEVENT 0 + +/*------------------------------------------------------------------------------------------------*/ +/* Internal prototypes */ +/*------------------------------------------------------------------------------------------------*/ +static Fsm_Act_t Fsm_StateEval(CFsm *self); + +/*------------------------------------------------------------------------------------------------*/ +/* Implementation */ +/*------------------------------------------------------------------------------------------------*/ +/*! \brief Constructor of the Finite State Machine class. + * \param self Instance pointer + * \param inst_ptr Instance pointer used for state machine actions + * \param trans_table_ptr Pointer to transition table + * \param num_events Maximum number of events + * \param init_state Initialization state to start with + */ +void Fsm_Ctor(CFsm *self, void *inst_ptr, const Fsm_StateElem_t *trans_table_ptr, + uint8_t num_events, int8_t init_state) +{ + MISC_MEM_SET(self, 0, sizeof(*self)); + self->inst_ptr = inst_ptr; + self->event_occured = FSM_E_NILEVENT; /* Clear event variable */ + self->current_state = init_state; /* Set initialization state */ + self->transition_table_ptr = trans_table_ptr; /* Set pointer to given transition table */ + self->num_events = num_events; /* Store maximum number of events */ + self->internal_state = FSM_STATE_IDLE; /* Clear internal state */ +} + +/*! \brief Determine required action + * \details This function determines the required action in dependency of the current state + * and the triggered event. The current state will be transitioned to the next state. + * The internal event variable will be cleared and the determined action will be + * returned. + * \param self Instance pointer + * \return Determined required action + * \return \c NULL if no action is required + */ +static Fsm_Act_t Fsm_StateEval(CFsm *self) +{ + Fsm_Act_t retval = NULL; /* Set default return value */ + + if(self->event_occured != FSM_E_NILEVENT) /* Event occurred ? */ + { + if((uint8_t)self->event_occured <= self->num_events) /* Check if event is valid */ + { + /* Get state-matrix-element in dependency of current state and triggered event */ + uint8_t i = ((uint8_t)self->current_state * self->num_events) + (uint8_t)self->event_occured; + Fsm_StateElem_t stateEvaluation = self->transition_table_ptr[i]; + self->current_state = stateEvaluation.next_state; /* Set new state */ + self->internal_state = FSM_STATE_IDLE; /* Set internal state to \c IDLE */ + retval = stateEvaluation.action_fptr; /* Return required action */ + } + else + { + self->internal_state = FSM_STATE_ERROR; /* Error occurred: Unknown event */ + } + + self->event_occured = FSM_E_NILEVENT; /* Clear event variable */ + } + + return retval; +} + +/*! \brief Service function for Finite State Machines + * \details The state machine will be serviced until it will be stopped by the user or no + * further event is triggered. If a state transition occurred the associated action + * will be executed. + * \param self Instance pointer + * \return Internal state of the state machine (see \ref Fsm_State_t). + */ +Fsm_State_t Fsm_Service(CFsm *self) +{ + /* Internal state is set to \c FSM_STATE_SERVICE and any event is triggered? */ + while((self->internal_state == FSM_STATE_SERVICE) && (self->event_occured != FSM_E_NILEVENT)) + { + Fsm_Act_t action_fptr = Fsm_StateEval(self); /* Execute state transition */ + if(action_fptr != NULL) /* Action required ? */ + { + (*action_fptr)(self->inst_ptr); /* Execute action */ + } + } + + return self->internal_state; /* Return internal state machine state */ +} + +/*! \brief Set an event + * \details This function sets the given event and triggers the service for the given + * state machine. + * \param self Instance pointer + * \param e New event + */ +void Fsm_SetEvent(CFsm *self, int8_t e) +{ + if(self->internal_state != FSM_STATE_END) + { + self->event_occured = e; /* Set new event */ + self->internal_state = FSM_STATE_SERVICE; /* Set internal state to \c FSM_STATE_SERVICE */ + } +} + +/*! \brief Sets the wait state + * \details This function sets the given state state machine into the wait state. The state + * machine stops and must be re-triggered. + * \param self Instance pointer + */ +void Fsm_Wait(CFsm *self) +{ + if(self->internal_state != FSM_STATE_END) + { + self->internal_state = FSM_STATE_WAIT; /* Set internal state to \c WAIT */ + } +} + +/*! \brief End processing of the state machine + * \details If this function is called the given state machine will be stopped immediately. + * \param self Instance pointer + */ +void Fsm_End(CFsm *self) +{ + self->internal_state = FSM_STATE_END; /* Set internal state to \c END */ +} + +/*! + * @} + * \endcond + */ + +/*------------------------------------------------------------------------------------------------*/ +/* End of file */ +/*------------------------------------------------------------------------------------------------*/ + |