1 /**
2  * $Id: fsm.c,v 1.3 2001/06/18 16:49:19 felfert Exp $
3  *
4  * A generic FSM based on fsm used in isdn4linux
5  *
6  */
7 
8 #include "fsm.h"
9 #include <linux/version.h>
10 #include <linux/config.h>
11 #include <linux/module.h>
12 
13 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,int order)14 init_fsm(char *name, const char **state_names, const char **event_names, int nr_states,
15 		int nr_events, const fsm_node *tmpl, int tmpl_len, int order)
16 {
17 	int i;
18 	fsm_instance *this;
19 	fsm_function_t *m;
20 	fsm *f;
21 
22 	this = (fsm_instance *)kmalloc(sizeof(fsm_instance), order);
23 	if (this == NULL) {
24 		printk(KERN_WARNING
25 			"fsm(%s): init_fsm: Couldn't alloc instance\n", name);
26 		return NULL;
27 	}
28 	memset(this, 0, sizeof(fsm_instance));
29 	strncpy(this->name, name, sizeof(this->name));
30 
31 	f = (fsm *)kmalloc(sizeof(fsm), order);
32 	if (f == NULL) {
33 		printk(KERN_WARNING
34 			"fsm(%s): init_fsm: Couldn't alloc fsm\n", name);
35 		kfree_fsm(this);
36 		return NULL;
37 	}
38 	memset(f, 0, sizeof(fsm));
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 = (fsm_function_t *)kmalloc(
46 			sizeof(fsm_function_t) * nr_states * nr_events, order);
47 	if (m == NULL) {
48 		printk(KERN_WARNING
49 			"fsm(%s): init_fsm: Couldn't alloc jumptable\n", name);
50 		kfree_fsm(this);
51 		return NULL;
52 	}
53 	memset(m, 0, sizeof(fsm_function_t) * f->nr_states * f->nr_events);
54 	f->jumpmatrix = m;
55 
56 	for (i = 0; i < tmpl_len; i++) {
57 		if ((tmpl[i].cond_state >= nr_states) ||
58 		    (tmpl[i].cond_event >= nr_events)   ) {
59 			printk(KERN_ERR
60 				"fsm(%s): init_fsm: Bad template l=%d st(%ld/%ld) ev(%ld/%ld)\n",
61 				name, i, (long)tmpl[i].cond_state, (long)f->nr_states,
62 				(long)tmpl[i].cond_event, (long)f->nr_events);
63 			kfree_fsm(this);
64 			return NULL;
65 		} else
66 			m[nr_states * tmpl[i].cond_event + tmpl[i].cond_state] =
67 				tmpl[i].function;
68 	}
69 	return this;
70 }
71 
72 void
kfree_fsm(fsm_instance * this)73 kfree_fsm(fsm_instance *this)
74 {
75 	if (this) {
76 		if (this->f) {
77 			if (this->f->jumpmatrix)
78 				kfree(this->f->jumpmatrix);
79 			kfree(this->f);
80 		}
81 		kfree(this);
82 	} else
83 		printk(KERN_WARNING
84 			"fsm: kfree_fsm called with NULL argument\n");
85 }
86 
87 #if FSM_DEBUG_HISTORY
88 void
fsm_print_history(fsm_instance * fi)89 fsm_print_history(fsm_instance *fi)
90 {
91 	int idx = 0;
92 	int i;
93 
94 	if (fi->history_size >= FSM_HISTORY_SIZE)
95 		idx = fi->history_index;
96 
97 	printk(KERN_DEBUG "fsm(%s): History:\n", fi->name);
98 	for (i = 0; i < fi->history_size; i++) {
99 		int e = fi->history[idx].event;
100 		int s = fi->history[idx++].state;
101 		idx %= FSM_HISTORY_SIZE;
102 		if (e == -1)
103 			printk(KERN_DEBUG "  S=%s\n",
104 			       fi->f->state_names[s]);
105 		else
106 			printk(KERN_DEBUG "  S=%s E=%s\n",
107 			       fi->f->state_names[s],
108 			       fi->f->event_names[e]);
109 	}
110 	fi->history_size = fi->history_index = 0;
111 }
112 
113 void
fsm_record_history(fsm_instance * fi,int state,int event)114 fsm_record_history(fsm_instance *fi, int state, int event)
115 {
116 	fi->history[fi->history_index].state = state;
117 	fi->history[fi->history_index++].event = event;
118 	fi->history_index %= FSM_HISTORY_SIZE;
119 	if (fi->history_size < FSM_HISTORY_SIZE)
120 		fi->history_size++;
121 }
122 #endif
123 
124 const char *
fsm_getstate_str(fsm_instance * fi)125 fsm_getstate_str(fsm_instance *fi)
126 {
127 	int st = atomic_read(&fi->state);
128 	if (st >= fi->f->nr_states)
129 		return "Invalid";
130 	return fi->f->state_names[st];
131 }
132 
133 static void
fsm_expire_timer(fsm_timer * this)134 fsm_expire_timer(fsm_timer *this)
135 {
136 #if FSM_TIMER_DEBUG
137 	printk(KERN_DEBUG "fsm(%s): Timer %p expired\n",
138 	       this->fi->name, this);
139 #endif
140 	fsm_event(this->fi, this->expire_event, this->event_arg);
141 }
142 
143 void
fsm_settimer(fsm_instance * fi,fsm_timer * this)144 fsm_settimer(fsm_instance *fi, fsm_timer *this)
145 {
146 	this->fi = fi;
147 	this->tl.function = (void *)fsm_expire_timer;
148 	this->tl.data = (long)this;
149 #if FSM_TIMER_DEBUG
150 	printk(KERN_DEBUG "fsm(%s): Create timer %p\n", fi->name,
151 	       this);
152 #endif
153 	init_timer(&this->tl);
154 }
155 
156 void
fsm_deltimer(fsm_timer * this)157 fsm_deltimer(fsm_timer *this)
158 {
159 #if FSM_TIMER_DEBUG
160 	printk(KERN_DEBUG "fsm(%s): Delete timer %p\n", this->fi->name,
161 		this);
162 #endif
163 	del_timer(&this->tl);
164 }
165 
166 int
fsm_addtimer(fsm_timer * this,int millisec,int event,void * arg)167 fsm_addtimer(fsm_timer *this, int millisec, int event, void *arg)
168 {
169 
170 #if FSM_TIMER_DEBUG
171 	printk(KERN_DEBUG "fsm(%s): Add timer %p %dms\n",
172 	       this->fi->name, this, millisec);
173 #endif
174 
175 #if LINUX_VERSION_CODE >= 0x020300
176 	if (this->tl.list.next || this->tl.list.prev) {
177 		printk(KERN_WARNING "fsm(%s): timer already active!\n",
178 			this->fi->name);
179 		return -1;
180 	}
181 #else
182 	if (this->tl.next || this->tl.prev) {
183 		printk(KERN_WARNING "fsm(%s): timer already active!\n",
184 			this->fi->name);
185 		return -1;
186 	}
187 #endif
188 	init_timer(&this->tl);
189 	this->tl.function = (void *)fsm_expire_timer;
190 	this->tl.data = (long)this;
191 	this->expire_event = event;
192 	this->event_arg = arg;
193 	this->tl.expires = jiffies + (millisec * HZ) / 1000;
194 	add_timer(&this->tl);
195 	return 0;
196 }
197 
198 void
fsm_modtimer(fsm_timer * this,int millisec,int event,void * arg)199 fsm_modtimer(fsm_timer *this, int millisec, int event, void *arg)
200 {
201 
202 #if FSM_TIMER_DEBUG
203 	printk(KERN_DEBUG "fsm(%s): Restart timer %p %dms\n",
204 		this->fi->name, this, millisec);
205 #endif
206 
207 #if LINUX_VERSION_CODE >= 0x020300
208 	if (this->tl.list.next || this->tl.list.prev)
209 		del_timer(&this->tl);
210 #else
211 	if (this->tl.next || this->tl.prev)
212 		del_timer(&this->tl);
213 #endif
214 	init_timer(&this->tl);
215 	this->tl.function = (void *)fsm_expire_timer;
216 	this->tl.data = (long)this;
217 	this->expire_event = event;
218 	this->event_arg = arg;
219 	this->tl.expires = jiffies + (millisec * HZ) / 1000;
220 	add_timer(&this->tl);
221 }
222 
223 EXPORT_SYMBOL(init_fsm);
224 EXPORT_SYMBOL(kfree_fsm);
225 EXPORT_SYMBOL(fsm_settimer);
226 EXPORT_SYMBOL(fsm_deltimer);
227 EXPORT_SYMBOL(fsm_addtimer);
228 EXPORT_SYMBOL(fsm_modtimer);
229 EXPORT_SYMBOL(fsm_getstate_str);
230 
231 #if FSM_DEBUG_HISTORY
232 EXPORT_SYMBOL(fsm_print_history);
233 EXPORT_SYMBOL(fsm_record_history);
234 #endif
235