xref: /btstack/src/btstack_fsm.c (revision bb8a927b64a2bed4835a6cf12ebf71eb29487bd9)

/*
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 * modification, are permitted provided that the following conditions
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 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
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/**
 * @title Finite State Machine (FSM)
 *
 */
#define BTSTACK_FILE__ "btstack_fsm.c"

#include <stddef.h>

#include "btstack_fsm.h"

#include "btstack_config.h"
#include "btstack_debug.h"

static btstack_fsm_event_t const entry_evt = { BTSTACK_FSM_ENTRY_SIG };
static btstack_fsm_event_t const exit_evt = { BTSTACK_FSM_EXIT_SIG };

btstack_fsm_state_t btstack_fsm_transit(btstack_fsm_t *me, btstack_fsm_state_handler_t target) {
    me->state = target;
    return BTSTACK_FSM_TRAN_STATUS;
}

void btstack_fsm_constructor(btstack_fsm_t * const me, btstack_fsm_state_handler_t initial) {
    me->state = initial;
}

void btstack_fsm_init(btstack_fsm_t * const me, btstack_fsm_event_t const * const e) {
    btstack_assert(me->state != NULL);
    me->state(me, e);
    me->state(me, &entry_evt);
}

btstack_fsm_state_t btstack_fsm_dispatch(btstack_fsm_t * const me, btstack_fsm_event_t const * const e) {
    btstack_fsm_state_t status;
    btstack_fsm_state_handler_t prev_state = me->state;
    btstack_assert( me->state != NULL );

    status = me->state(me, e);

    if( status == BTSTACK_FSM_TRAN_STATUS ) {
        prev_state(me, &exit_evt);
        me->state(me, &entry_evt);
    }
    return status;
}

void btstack_fsm_dispatch_until(btstack_fsm_t * const me, btstack_fsm_event_t const * const e) {
    btstack_fsm_state_t status;
    do {
        status = btstack_fsm_dispatch( me, e );
    } while( status == BTSTACK_FSM_TRAN_STATUS );
}