1 /** 2 * A generic FSM based on fsm used in isdn4linux 3 * 4 */ 5 6 #include "fsm.h" 7 #include <linux/config.h> 8 #include <linux/module.h> 9 #include <linux/timer.h> 10 11 MODULE_AUTHOR("(C) 2000 IBM Corp. by Fritz Elfert (felfert@millenux.com)"); 12 MODULE_DESCRIPTION("Finite state machine helper functions"); 13 MODULE_LICENSE("GPL"); 14 15 fsm_instance * 16 init_fsm(char *name, const char **state_names, const char **event_names, int nr_states, 17 int nr_events, const fsm_node *tmpl, int tmpl_len, gfp_t order) 18 { 19 int i; 20 fsm_instance *this; 21 fsm_function_t *m; 22 fsm *f; 23 24 this = kzalloc(sizeof(fsm_instance), order); 25 if (this == NULL) { 26 printk(KERN_WARNING 27 "fsm(%s): init_fsm: Couldn't alloc instance\n", name); 28 return NULL; 29 } 30 strlcpy(this->name, name, sizeof(this->name)); 31 32 f = kzalloc(sizeof(fsm), order); 33 if (f == NULL) { 34 printk(KERN_WARNING 35 "fsm(%s): init_fsm: Couldn't alloc fsm\n", name); 36 kfree_fsm(this); 37 return NULL; 38 } 39 f->nr_events = nr_events; 40 f->nr_states = nr_states; 41 f->event_names = event_names; 42 f->state_names = state_names; 43 this->f = f; 44 45 m = kcalloc(nr_states*nr_events, sizeof(fsm_function_t), order); 46 if (m == NULL) { 47 printk(KERN_WARNING 48 "fsm(%s): init_fsm: Couldn't alloc jumptable\n", name); 49 kfree_fsm(this); 50 return NULL; 51 } 52 f->jumpmatrix = m; 53 54 for (i = 0; i < tmpl_len; i++) { 55 if ((tmpl[i].cond_state >= nr_states) || 56 (tmpl[i].cond_event >= nr_events) ) { 57 printk(KERN_ERR 58 "fsm(%s): init_fsm: Bad template l=%d st(%ld/%ld) ev(%ld/%ld)\n", 59 name, i, (long)tmpl[i].cond_state, (long)f->nr_states, 60 (long)tmpl[i].cond_event, (long)f->nr_events); 61 kfree_fsm(this); 62 return NULL; 63 } else 64 m[nr_states * tmpl[i].cond_event + tmpl[i].cond_state] = 65 tmpl[i].function; 66 } 67 return this; 68 } 69 70 void 71 kfree_fsm(fsm_instance *this) 72 { 73 if (this) { 74 if (this->f) { 75 kfree(this->f->jumpmatrix); 76 kfree(this->f); 77 } 78 kfree(this); 79 } else 80 printk(KERN_WARNING 81 "fsm: kfree_fsm called with NULL argument\n"); 82 } 83 84 #if FSM_DEBUG_HISTORY 85 void 86 fsm_print_history(fsm_instance *fi) 87 { 88 int idx = 0; 89 int i; 90 91 if (fi->history_size >= FSM_HISTORY_SIZE) 92 idx = fi->history_index; 93 94 printk(KERN_DEBUG "fsm(%s): History:\n", fi->name); 95 for (i = 0; i < fi->history_size; i++) { 96 int e = fi->history[idx].event; 97 int s = fi->history[idx++].state; 98 idx %= FSM_HISTORY_SIZE; 99 if (e == -1) 100 printk(KERN_DEBUG " S=%s\n", 101 fi->f->state_names[s]); 102 else 103 printk(KERN_DEBUG " S=%s E=%s\n", 104 fi->f->state_names[s], 105 fi->f->event_names[e]); 106 } 107 fi->history_size = fi->history_index = 0; 108 } 109 110 void 111 fsm_record_history(fsm_instance *fi, int state, int event) 112 { 113 fi->history[fi->history_index].state = state; 114 fi->history[fi->history_index++].event = event; 115 fi->history_index %= FSM_HISTORY_SIZE; 116 if (fi->history_size < FSM_HISTORY_SIZE) 117 fi->history_size++; 118 } 119 #endif 120 121 const char * 122 fsm_getstate_str(fsm_instance *fi) 123 { 124 int st = atomic_read(&fi->state); 125 if (st >= fi->f->nr_states) 126 return "Invalid"; 127 return fi->f->state_names[st]; 128 } 129 130 static void 131 fsm_expire_timer(fsm_timer *this) 132 { 133 #if FSM_TIMER_DEBUG 134 printk(KERN_DEBUG "fsm(%s): Timer %p expired\n", 135 this->fi->name, this); 136 #endif 137 fsm_event(this->fi, this->expire_event, this->event_arg); 138 } 139 140 void 141 fsm_settimer(fsm_instance *fi, fsm_timer *this) 142 { 143 this->fi = fi; 144 this->tl.function = (void *)fsm_expire_timer; 145 this->tl.data = (long)this; 146 #if FSM_TIMER_DEBUG 147 printk(KERN_DEBUG "fsm(%s): Create timer %p\n", fi->name, 148 this); 149 #endif 150 init_timer(&this->tl); 151 } 152 153 void 154 fsm_deltimer(fsm_timer *this) 155 { 156 #if FSM_TIMER_DEBUG 157 printk(KERN_DEBUG "fsm(%s): Delete timer %p\n", this->fi->name, 158 this); 159 #endif 160 del_timer(&this->tl); 161 } 162 163 int 164 fsm_addtimer(fsm_timer *this, int millisec, int event, void *arg) 165 { 166 167 #if FSM_TIMER_DEBUG 168 printk(KERN_DEBUG "fsm(%s): Add timer %p %dms\n", 169 this->fi->name, this, millisec); 170 #endif 171 172 init_timer(&this->tl); 173 this->tl.function = (void *)fsm_expire_timer; 174 this->tl.data = (long)this; 175 this->expire_event = event; 176 this->event_arg = arg; 177 this->tl.expires = jiffies + (millisec * HZ) / 1000; 178 add_timer(&this->tl); 179 return 0; 180 } 181 182 /* FIXME: this function is never used, why */ 183 void 184 fsm_modtimer(fsm_timer *this, int millisec, int event, void *arg) 185 { 186 187 #if FSM_TIMER_DEBUG 188 printk(KERN_DEBUG "fsm(%s): Restart timer %p %dms\n", 189 this->fi->name, this, millisec); 190 #endif 191 192 del_timer(&this->tl); 193 init_timer(&this->tl); 194 this->tl.function = (void *)fsm_expire_timer; 195 this->tl.data = (long)this; 196 this->expire_event = event; 197 this->event_arg = arg; 198 this->tl.expires = jiffies + (millisec * HZ) / 1000; 199 add_timer(&this->tl); 200 } 201 202 EXPORT_SYMBOL(init_fsm); 203 EXPORT_SYMBOL(kfree_fsm); 204 EXPORT_SYMBOL(fsm_settimer); 205 EXPORT_SYMBOL(fsm_deltimer); 206 EXPORT_SYMBOL(fsm_addtimer); 207 EXPORT_SYMBOL(fsm_modtimer); 208 EXPORT_SYMBOL(fsm_getstate_str); 209 210 #if FSM_DEBUG_HISTORY 211 EXPORT_SYMBOL(fsm_print_history); 212 EXPORT_SYMBOL(fsm_record_history); 213 #endif 214