xref: /btstack/src/btstack_fsm.c (revision f05358500e612946f8c340b1f11e5703dafd65f8)
1 /*
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37 
38 /**
39  * @title Finite State Machine (FSM)
40  *
41  */
42 #define BTSTACK_FILE__ "btstack_fsm.c"
43 
44 #include <stddef.h>
45 
46 #include "btstack_fsm.h"
47 
48 #include "btstack_config.h"
49 #include "btstack_debug.h"
50 
51 static btstack_fsm_event_t const entry_evt = { BTSTACK_FSM_ENTRY_SIG };
52 static btstack_fsm_event_t const exit_evt = { BTSTACK_FSM_EXIT_SIG };
53 
54 btstack_fsm_state_t btstack_fsm_transit(btstack_fsm_t *me, btstack_fsm_state_handler_t target) {
55     me->state = target;
56     return BTSTACK_FSM_TRAN_STATUS;
57 }
58 
59 void btstack_fsm_constructor(btstack_fsm_t * const me, btstack_fsm_state_handler_t initial) {
60     me->state = initial;
61 }
62 
63 void btstack_fsm_init(btstack_fsm_t * const me, btstack_fsm_event_t const * const e) {
64     btstack_assert(me->state != NULL);
65     me->state(me, e);
66     me->state(me, &entry_evt);
67 }
68 
69 btstack_fsm_state_t btstack_fsm_dispatch(btstack_fsm_t * const me, btstack_fsm_event_t const * const e) {
70     btstack_fsm_state_t status;
71     btstack_fsm_state_handler_t prev_state = me->state;
72     btstack_assert( me->state != NULL );
73 
74     status = me->state(me, e);
75 
76     if( status == BTSTACK_FSM_TRAN_STATUS ) {
77         prev_state(me, &exit_evt);
78         me->state(me, &entry_evt);
79     }
80     return status;
81 }
82 
83 void btstack_fsm_dispatch_until(btstack_fsm_t * const me, btstack_fsm_event_t const * const e) {
84     btstack_fsm_state_t status;
85     do {
86         status = btstack_fsm_dispatch( me, e );
87     } while( status == BTSTACK_FSM_TRAN_STATUS );
88 }
89 
90