Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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, |
Al Viro | b4e3ca1 | 2005-10-21 03:22:34 -0400 | [diff] [blame] | 19 | int nr_events, const fsm_node *tmpl, int tmpl_len, gfp_t order) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | if (this->f->jumpmatrix) |
| 82 | kfree(this->f->jumpmatrix); |
| 83 | kfree(this->f); |
| 84 | } |
| 85 | kfree(this); |
| 86 | } else |
| 87 | printk(KERN_WARNING |
| 88 | "fsm: kfree_fsm called with NULL argument\n"); |
| 89 | } |
| 90 | |
| 91 | #if FSM_DEBUG_HISTORY |
| 92 | void |
| 93 | fsm_print_history(fsm_instance *fi) |
| 94 | { |
| 95 | int idx = 0; |
| 96 | int i; |
| 97 | |
| 98 | if (fi->history_size >= FSM_HISTORY_SIZE) |
| 99 | idx = fi->history_index; |
| 100 | |
| 101 | printk(KERN_DEBUG "fsm(%s): History:\n", fi->name); |
| 102 | for (i = 0; i < fi->history_size; i++) { |
| 103 | int e = fi->history[idx].event; |
| 104 | int s = fi->history[idx++].state; |
| 105 | idx %= FSM_HISTORY_SIZE; |
| 106 | if (e == -1) |
| 107 | printk(KERN_DEBUG " S=%s\n", |
| 108 | fi->f->state_names[s]); |
| 109 | else |
| 110 | printk(KERN_DEBUG " S=%s E=%s\n", |
| 111 | fi->f->state_names[s], |
| 112 | fi->f->event_names[e]); |
| 113 | } |
| 114 | fi->history_size = fi->history_index = 0; |
| 115 | } |
| 116 | |
| 117 | void |
| 118 | fsm_record_history(fsm_instance *fi, int state, int event) |
| 119 | { |
| 120 | fi->history[fi->history_index].state = state; |
| 121 | fi->history[fi->history_index++].event = event; |
| 122 | fi->history_index %= FSM_HISTORY_SIZE; |
| 123 | if (fi->history_size < FSM_HISTORY_SIZE) |
| 124 | fi->history_size++; |
| 125 | } |
| 126 | #endif |
| 127 | |
| 128 | const char * |
| 129 | fsm_getstate_str(fsm_instance *fi) |
| 130 | { |
| 131 | int st = atomic_read(&fi->state); |
| 132 | if (st >= fi->f->nr_states) |
| 133 | return "Invalid"; |
| 134 | return fi->f->state_names[st]; |
| 135 | } |
| 136 | |
| 137 | static void |
| 138 | fsm_expire_timer(fsm_timer *this) |
| 139 | { |
| 140 | #if FSM_TIMER_DEBUG |
| 141 | printk(KERN_DEBUG "fsm(%s): Timer %p expired\n", |
| 142 | this->fi->name, this); |
| 143 | #endif |
| 144 | fsm_event(this->fi, this->expire_event, this->event_arg); |
| 145 | } |
| 146 | |
| 147 | void |
| 148 | fsm_settimer(fsm_instance *fi, fsm_timer *this) |
| 149 | { |
| 150 | this->fi = fi; |
| 151 | this->tl.function = (void *)fsm_expire_timer; |
| 152 | this->tl.data = (long)this; |
| 153 | #if FSM_TIMER_DEBUG |
| 154 | printk(KERN_DEBUG "fsm(%s): Create timer %p\n", fi->name, |
| 155 | this); |
| 156 | #endif |
| 157 | init_timer(&this->tl); |
| 158 | } |
| 159 | |
| 160 | void |
| 161 | fsm_deltimer(fsm_timer *this) |
| 162 | { |
| 163 | #if FSM_TIMER_DEBUG |
| 164 | printk(KERN_DEBUG "fsm(%s): Delete timer %p\n", this->fi->name, |
| 165 | this); |
| 166 | #endif |
| 167 | del_timer(&this->tl); |
| 168 | } |
| 169 | |
| 170 | int |
| 171 | fsm_addtimer(fsm_timer *this, int millisec, int event, void *arg) |
| 172 | { |
| 173 | |
| 174 | #if FSM_TIMER_DEBUG |
| 175 | printk(KERN_DEBUG "fsm(%s): Add timer %p %dms\n", |
| 176 | this->fi->name, this, millisec); |
| 177 | #endif |
| 178 | |
| 179 | init_timer(&this->tl); |
| 180 | this->tl.function = (void *)fsm_expire_timer; |
| 181 | this->tl.data = (long)this; |
| 182 | this->expire_event = event; |
| 183 | this->event_arg = arg; |
| 184 | this->tl.expires = jiffies + (millisec * HZ) / 1000; |
| 185 | add_timer(&this->tl); |
| 186 | return 0; |
| 187 | } |
| 188 | |
| 189 | /* FIXME: this function is never used, why */ |
| 190 | void |
| 191 | fsm_modtimer(fsm_timer *this, int millisec, int event, void *arg) |
| 192 | { |
| 193 | |
| 194 | #if FSM_TIMER_DEBUG |
| 195 | printk(KERN_DEBUG "fsm(%s): Restart timer %p %dms\n", |
| 196 | this->fi->name, this, millisec); |
| 197 | #endif |
| 198 | |
| 199 | del_timer(&this->tl); |
| 200 | init_timer(&this->tl); |
| 201 | this->tl.function = (void *)fsm_expire_timer; |
| 202 | this->tl.data = (long)this; |
| 203 | this->expire_event = event; |
| 204 | this->event_arg = arg; |
| 205 | this->tl.expires = jiffies + (millisec * HZ) / 1000; |
| 206 | add_timer(&this->tl); |
| 207 | } |
| 208 | |
| 209 | EXPORT_SYMBOL(init_fsm); |
| 210 | EXPORT_SYMBOL(kfree_fsm); |
| 211 | EXPORT_SYMBOL(fsm_settimer); |
| 212 | EXPORT_SYMBOL(fsm_deltimer); |
| 213 | EXPORT_SYMBOL(fsm_addtimer); |
| 214 | EXPORT_SYMBOL(fsm_modtimer); |
| 215 | EXPORT_SYMBOL(fsm_getstate_str); |
| 216 | |
| 217 | #if FSM_DEBUG_HISTORY |
| 218 | EXPORT_SYMBOL(fsm_print_history); |
| 219 | EXPORT_SYMBOL(fsm_record_history); |
| 220 | #endif |