1 /** 2 * $Id: fsm.c,v 1.6 2003/10/15 11:37:29 mschwide Exp $ 3 * 4 * A generic FSM based on fsm used in isdn4linux 5 * 6 */ 7 8 #include "fsm.h" 9 #include <linux/config.h> 10 #include <linux/module.h> 11 #include <linux/timer.h> 12 13 MODULE_AUTHOR("(C) 2000 IBM Corp. by Fritz Elfert (felfert@millenux.com)"); 14 MODULE_DESCRIPTION("Finite state machine helper functions"); 15 MODULE_LICENSE("GPL"); 16 17 fsm_instance * 18 init_fsm(char *name, const char **state_names, const char **event_names, int nr_states, 19 int nr_events, const fsm_node *tmpl, int tmpl_len, gfp_t order) 20 { 21 int i; 22 fsm_instance *this; 23 fsm_function_t *m; 24 fsm *f; 25 26 this = (fsm_instance *)kmalloc(sizeof(fsm_instance), order); 27 if (this == NULL) { 28 printk(KERN_WARNING 29 "fsm(%s): init_fsm: Couldn't alloc instance\n", name); 30 return NULL; 31 } 32 memset(this, 0, sizeof(fsm_instance)); 33 strlcpy(this->name, name, sizeof(this->name)); 34 35 f = (fsm *)kmalloc(sizeof(fsm), order); 36 if (f == NULL) { 37 printk(KERN_WARNING 38 "fsm(%s): init_fsm: Couldn't alloc fsm\n", name); 39 kfree_fsm(this); 40 return NULL; 41 } 42 memset(f, 0, sizeof(fsm)); 43 f->nr_events = nr_events; 44 f->nr_states = nr_states; 45 f->event_names = event_names; 46 f->state_names = state_names; 47 this->f = f; 48 49 m = (fsm_function_t *)kmalloc( 50 sizeof(fsm_function_t) * nr_states * nr_events, order); 51 if (m == NULL) { 52 printk(KERN_WARNING 53 "fsm(%s): init_fsm: Couldn't alloc jumptable\n", name); 54 kfree_fsm(this); 55 return NULL; 56 } 57 memset(m, 0, sizeof(fsm_function_t) * f->nr_states * f->nr_events); 58 f->jumpmatrix = m; 59 60 for (i = 0; i < tmpl_len; i++) { 61 if ((tmpl[i].cond_state >= nr_states) || 62 (tmpl[i].cond_event >= nr_events) ) { 63 printk(KERN_ERR 64 "fsm(%s): init_fsm: Bad template l=%d st(%ld/%ld) ev(%ld/%ld)\n", 65 name, i, (long)tmpl[i].cond_state, (long)f->nr_states, 66 (long)tmpl[i].cond_event, (long)f->nr_events); 67 kfree_fsm(this); 68 return NULL; 69 } else 70 m[nr_states * tmpl[i].cond_event + tmpl[i].cond_state] = 71 tmpl[i].function; 72 } 73 return this; 74 } 75 76 void 77 kfree_fsm(fsm_instance *this) 78 { 79 if (this) { 80 if (this->f) { 81 kfree(this->f->jumpmatrix); 82 kfree(this->f); 83 } 84 kfree(this); 85 } else 86 printk(KERN_WARNING 87 "fsm: kfree_fsm called with NULL argument\n"); 88 } 89 90 #if FSM_DEBUG_HISTORY 91 void 92 fsm_print_history(fsm_instance *fi) 93 { 94 int idx = 0; 95 int i; 96 97 if (fi->history_size >= FSM_HISTORY_SIZE) 98 idx = fi->history_index; 99 100 printk(KERN_DEBUG "fsm(%s): History:\n", fi->name); 101 for (i = 0; i < fi->history_size; i++) { 102 int e = fi->history[idx].event; 103 int s = fi->history[idx++].state; 104 idx %= FSM_HISTORY_SIZE; 105 if (e == -1) 106 printk(KERN_DEBUG " S=%s\n", 107 fi->f->state_names[s]); 108 else 109 printk(KERN_DEBUG " S=%s E=%s\n", 110 fi->f->state_names[s], 111 fi->f->event_names[e]); 112 } 113 fi->history_size = fi->history_index = 0; 114 } 115 116 void 117 fsm_record_history(fsm_instance *fi, int state, int event) 118 { 119 fi->history[fi->history_index].state = state; 120 fi->history[fi->history_index++].event = event; 121 fi->history_index %= FSM_HISTORY_SIZE; 122 if (fi->history_size < FSM_HISTORY_SIZE) 123 fi->history_size++; 124 } 125 #endif 126 127 const char * 128 fsm_getstate_str(fsm_instance *fi) 129 { 130 int st = atomic_read(&fi->state); 131 if (st >= fi->f->nr_states) 132 return "Invalid"; 133 return fi->f->state_names[st]; 134 } 135 136 static void 137 fsm_expire_timer(fsm_timer *this) 138 { 139 #if FSM_TIMER_DEBUG 140 printk(KERN_DEBUG "fsm(%s): Timer %p expired\n", 141 this->fi->name, this); 142 #endif 143 fsm_event(this->fi, this->expire_event, this->event_arg); 144 } 145 146 void 147 fsm_settimer(fsm_instance *fi, fsm_timer *this) 148 { 149 this->fi = fi; 150 this->tl.function = (void *)fsm_expire_timer; 151 this->tl.data = (long)this; 152 #if FSM_TIMER_DEBUG 153 printk(KERN_DEBUG "fsm(%s): Create timer %p\n", fi->name, 154 this); 155 #endif 156 init_timer(&this->tl); 157 } 158 159 void 160 fsm_deltimer(fsm_timer *this) 161 { 162 #if FSM_TIMER_DEBUG 163 printk(KERN_DEBUG "fsm(%s): Delete timer %p\n", this->fi->name, 164 this); 165 #endif 166 del_timer(&this->tl); 167 } 168 169 int 170 fsm_addtimer(fsm_timer *this, int millisec, int event, void *arg) 171 { 172 173 #if FSM_TIMER_DEBUG 174 printk(KERN_DEBUG "fsm(%s): Add timer %p %dms\n", 175 this->fi->name, this, millisec); 176 #endif 177 178 init_timer(&this->tl); 179 this->tl.function = (void *)fsm_expire_timer; 180 this->tl.data = (long)this; 181 this->expire_event = event; 182 this->event_arg = arg; 183 this->tl.expires = jiffies + (millisec * HZ) / 1000; 184 add_timer(&this->tl); 185 return 0; 186 } 187 188 /* FIXME: this function is never used, why */ 189 void 190 fsm_modtimer(fsm_timer *this, int millisec, int event, void *arg) 191 { 192 193 #if FSM_TIMER_DEBUG 194 printk(KERN_DEBUG "fsm(%s): Restart timer %p %dms\n", 195 this->fi->name, this, millisec); 196 #endif 197 198 del_timer(&this->tl); 199 init_timer(&this->tl); 200 this->tl.function = (void *)fsm_expire_timer; 201 this->tl.data = (long)this; 202 this->expire_event = event; 203 this->event_arg = arg; 204 this->tl.expires = jiffies + (millisec * HZ) / 1000; 205 add_timer(&this->tl); 206 } 207 208 EXPORT_SYMBOL(init_fsm); 209 EXPORT_SYMBOL(kfree_fsm); 210 EXPORT_SYMBOL(fsm_settimer); 211 EXPORT_SYMBOL(fsm_deltimer); 212 EXPORT_SYMBOL(fsm_addtimer); 213 EXPORT_SYMBOL(fsm_modtimer); 214 EXPORT_SYMBOL(fsm_getstate_str); 215 216 #if FSM_DEBUG_HISTORY 217 EXPORT_SYMBOL(fsm_print_history); 218 EXPORT_SYMBOL(fsm_record_history); 219 #endif 220