/**
* $Id: fsm.c,v 1.6 2003/10/15 11:37:29 mschwide Exp $
*
* A generic FSM based on fsm used in isdn4linux
*
*/
#include "fsm.h"
#include <linux/config.h>
#include <linux/module.h>
#include <linux/timer.h>
MODULE_AUTHOR("(C) 2000 IBM Corp. by Fritz Elfert (felfert@millenux.com)");
MODULE_DESCRIPTION("Finite state machine helper functions");
MODULE_LICENSE("GPL");
fsm_instance *
init_fsm(char *name, const char **state_names, const char **event_names, int nr_states,
int nr_events, const fsm_node *tmpl, int tmpl_len, gfp_t order)
{
int i;
fsm_instance *this;
fsm_function_t *m;
fsm *f;
this = (fsm_instance *)kmalloc(sizeof(fsm_instance), order);
if (this == NULL) {
printk(KERN_WARNING
"fsm(%s): init_fsm: Couldn't alloc instance\n", name);
return NULL;
}
memset(this, 0, sizeof(fsm_instance));
strlcpy(this->name, name, sizeof(this->name));
f = (fsm *)kmalloc(sizeof(fsm), order);
if (f == NULL) {
printk(KERN_WARNING
"fsm(%s): init_fsm: Couldn't alloc fsm\n", name);
kfree_fsm(this);
return NULL;
}
memset(f, 0, sizeof(fsm));
f->nr_events = nr_events;
f->nr_states = nr_states;
f->event_names = event_names;
f->state_names = state_names;
this->f = f;
m = (fsm_function_t *)kmalloc(
sizeof(fsm_function_t) * nr_states * nr_events, order);
if (m == NULL) {
printk(KERN_WARNING
"fsm(%s): init_fsm: Couldn't alloc jumptable\n", name);
kfree_fsm(this);
return NULL;
}
memset(m, 0, sizeof(fsm_function_t) * f->nr_states * f->nr_events);
f->jumpmatrix = m;
for (i = 0; i < tmpl_len; i++) {
if ((tmpl[i].cond_state >= nr_states) ||
(tmpl[i].cond_event >= nr_events) ) {
printk(KERN_ERR
"fsm(%s): init_fsm: Bad template l=%d st(%ld/%ld) ev(%ld/%ld)\n",
name, i, (long)tmpl[i].cond_state, (long)f->nr_states,
(long)tmpl[i].cond_event, (long)f->nr_events);
kfree_fsm(this);
return NULL;
} else
m[nr_states * tmpl[i].cond_event + tmpl[i].cond_state] =
tmpl[i].function;
}
return this;
}
void
kfree_fsm(fsm_instance *this)
{
if (this) {
if (this->f) {
kfree(this->f->jumpmatrix);
kfree(this->f);
}
kfree(this);
} else
printk(KERN_WARNING
"fsm: kfree_fsm called with NULL argument\n");
}
#if FSM_DEBUG_HISTORY
void
fsm_print_history(fsm_instance *fi)
{
int idx = 0;
int i;
if (fi->history_size >= FSM_HISTORY_SIZE)
idx = fi->history_index;
printk(KERN_DEBUG "fsm(%s): History:\n", fi->name);
for (i = 0; i < fi->history_size; i++) {
int e = fi->history[idx].event;
int s = fi->history[idx++].state;
idx %= FSM_HISTORY_SIZE;
if (e == -1)
printk(KERN_DEBUG " S=%s\n",
fi->f->state_names[s]);
else
printk(KERN_DEBUG " S=%s E=%s\n",
fi->f->state_names[s],
fi->f->event_names[e]);
}
fi->history_size = fi->history_index = 0;
}
void
fsm_record_history(fsm_instance *fi, int state, int event)
{
fi->history[fi->history_index].state = state;
fi->history[fi->history_index++].event = event;
fi->history_index %= FSM_HISTORY_SIZE;
if (fi->history_size < FSM_HISTORY_SIZE)
fi->history_size++;
}
#endif
const char *
fsm_getstate_str(fsm_instance *fi)
{
int st = atomic_read(&fi->state);
if (st >= fi->f->nr_states)
return "Invalid";
return fi->f->state_names[st];
}
static void
fsm_expire_timer(fsm_timer *this)
{
#if FSM_TIMER_DEBUG
printk(KERN_DEBUG "fsm(%s): Timer %p expired\n",
this->fi->name, this);
#endif
fsm_event(this->fi, this->expire_event, this->event_arg);
}
void
fsm_settimer(fsm_instance *fi, fsm_timer *this)
{
this->fi = fi;
this->tl.function = (void *)fsm_expire_timer;
this->tl.data = (long)this;
#if FSM_TIMER_DEBUG
printk(KERN_DEBUG "fsm(%s): Create timer %p\n", fi->name,
this);
#endif
init_timer(&this->tl);
}
void
fsm_deltimer(fsm_timer *this)
{
#if FSM_TIMER_DEBUG
printk(KERN_DEBUG "fsm(%s): Delete timer %p\n", this->fi->name,
this);
#endif
del_timer(&this->tl);
}
int
fsm_addtimer(fsm_timer *this, int millisec, int event, void *arg)
{
#if FSM_TIMER_DEBUG
printk(KERN_DEBUG "fsm(%s): Add timer %p %dms\n",
this->fi->name, this, millisec);
#endif
init_timer(&this->tl);
this->tl.function = (void *)fsm_expire_timer;
this->tl.data = (long)this;
this->expire_event = event;
this->event_arg = arg;
this->tl.expires = jiffies + (millisec * HZ) / 1000;
add_timer(&this->tl);
return 0;
}
/* FIXME: this function is never used, why */
void
fsm_modtimer(fsm_timer *this, int millisec, int event, void *arg)
{
#if FSM_TIMER_DEBUG
printk(KERN_DEBUG "fsm(%s): Restart timer %p %dms\n",
this->fi->name, this, millisec);
#endif
del_timer(&this->tl);
init_timer(&this->tl);
this->tl.function = (void *)fsm_expire_timer;
this->tl.data = (long)this;
this->expire_event = event;
this->event_arg = arg;
this->tl.expires = jiffies + (millisec * HZ) / 1000;
add_timer(&this->tl);
}
EXPORT_SYMBOL(init_fsm);
EXPORT_SYMBOL(kfree_fsm);
EXPORT_SYMBOL(fsm_settimer);
EXPORT_SYMBOL(fsm_deltimer);
EXPORT_SYMBOL(fsm_addtimer);
EXPORT_SYMBOL(fsm_modtimer);
EXPORT_SYMBOL(fsm_getstate_str);
#if FSM_DEBUG_HISTORY
EXPORT_SYMBOL(fsm_print_history);
EXPORT_SYMBOL(fsm_record_history);
#endif
