xref: /freebsd/usr.sbin/ppp/timer.c (revision a8445737e740901f5f2c8d24c12ef7fc8b00134e)
1 /*
2  *		PPP Timer Processing Module
3  *
4  *	    Written by Toshiharu OHNO (tony-o@iij.ad.jp)
5  *
6  *   Copyright (C) 1993, Internet Initiative Japan, Inc. All rights reserverd.
7  *
8  * Redistribution and use in source and binary forms are permitted
9  * provided that the above copyright notice and this paragraph are
10  * duplicated in all such forms and that any documentation,
11  * advertising materials, and other materials related to such
12  * distribution and use acknowledge that the software was developed
13  * by the Internet Initiative Japan, Inc.  The name of the
14  * IIJ may not be used to endorse or promote products derived
15  * from this software without specific prior written permission.
16  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
18  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
19  *
20  * $Id: timer.c,v 1.30 1998/06/20 01:36:38 brian Exp $
21  *
22  *  TODO:
23  */
24 
25 #include <signal.h>
26 #include <stdio.h>
27 #include <sys/time.h>
28 #include <termios.h>
29 
30 #include "log.h"
31 #include "sig.h"
32 #include "timer.h"
33 #include "descriptor.h"
34 #include "prompt.h"
35 
36 static struct pppTimer *TimerList = NULL;
37 
38 static void StopTimerNoBlock(struct pppTimer *);
39 
40 static const char *
41 tState2Nam(u_int state)
42 {
43   static const char *StateNames[] = { "stopped", "running", "expired" };
44 
45   if (state >= sizeof StateNames / sizeof StateNames[0])
46     return "unknown";
47   return StateNames[state];
48 }
49 
50 void
51 timer_Stop(struct pppTimer * tp)
52 {
53   int omask;
54 
55   omask = sigblock(sigmask(SIGALRM));
56   StopTimerNoBlock(tp);
57   sigsetmask(omask);
58 }
59 
60 void
61 timer_Start(struct pppTimer * tp)
62 {
63   struct pppTimer *t, *pt;
64   u_long ticks = 0;
65   int omask;
66 
67   omask = sigblock(sigmask(SIGALRM));
68 
69   if (tp->state != TIMER_STOPPED)
70     StopTimerNoBlock(tp);
71 
72   if (tp->load == 0) {
73     log_Printf(LogTIMER, "%s timer[%p] has 0 load!\n", tp->name, tp);
74     sigsetmask(omask);
75     return;
76   }
77   pt = NULL;
78   for (t = TimerList; t; t = t->next) {
79     if (ticks + t->rest >= tp->load)
80       break;
81     ticks += t->rest;
82     pt = t;
83   }
84 
85   tp->state = TIMER_RUNNING;
86   tp->rest = tp->load - ticks;
87 
88   if (t)
89     log_Printf(LogTIMER, "timer_Start: Inserting %s timer[%p] before %s "
90               "timer[%p], delta = %ld\n", tp->name, tp, t->name, t, tp->rest);
91   else
92     log_Printf(LogTIMER, "timer_Start: Inserting %s timer[%p]\n", tp->name, tp);
93 
94   /* Insert given *tp just before *t */
95   tp->next = t;
96   if (pt) {
97     pt->next = tp;
98   } else {
99     timer_InitService();
100     TimerList = tp;
101   }
102   if (t)
103     t->rest -= tp->rest;
104 
105   sigsetmask(omask);
106 }
107 
108 static void
109 StopTimerNoBlock(struct pppTimer * tp)
110 {
111   struct pppTimer *t, *pt;
112 
113   /*
114    * A RUNNING timer must be removed from TimerList (->next list).
115    * A STOPPED timer isn't in any list, but may have a bogus [e]next field.
116    * An EXPIRED timer is in the ->enext list.
117    */
118   if (tp->state != TIMER_RUNNING) {
119     tp->next = NULL;
120     tp->state = TIMER_STOPPED;
121     return;
122   }
123   pt = NULL;
124   for (t = TimerList; t != tp && t != NULL; t = t->next)
125     pt = t;
126   if (t) {
127     if (pt) {
128       pt->next = t->next;
129     } else {
130       TimerList = t->next;
131       if (TimerList == NULL)	/* Last one ? */
132 	timer_TermService();	/* Terminate Timer Service */
133     }
134     if (t->next)
135       t->next->rest += tp->rest;
136   } else
137     log_Printf(LogERROR, "Oops, %s timer not found!!\n", tp->name);
138 
139   tp->next = NULL;
140   tp->state = TIMER_STOPPED;
141 }
142 
143 static void
144 TimerService(void)
145 {
146   struct pppTimer *tp, *exp, *wt;
147 
148   if (log_IsKept(LogTIMER)) {
149     static time_t t;		/* Only show timers globally every second */
150     time_t n = time(NULL);
151 
152     if (n > t)
153       timer_Show(LogTIMER, NULL);
154     t = n;
155   }
156   tp = TimerList;
157   if (tp) {
158     tp->rest--;
159     if (tp->rest == 0) {
160 
161       /*
162        * Multiple timers may expires at once. Create list of expired timers.
163        */
164       exp = NULL;
165       do {
166 	tp->state = TIMER_EXPIRED;
167 	wt = tp->next;
168 	tp->enext = exp;
169 	exp = tp;
170 	tp = wt;
171       } while (tp && (tp->rest == 0));
172 
173       TimerList = tp;
174       if (TimerList == NULL)	/* No timers ? */
175 	timer_TermService();	/* Terminate Timer Service */
176 
177       /*
178        * Process all expired timers.
179        */
180       while (exp) {
181 #ifdef notdef
182 	timer_Stop(exp);
183 #endif
184 	if (exp->func)
185 	  (*exp->func) (exp->arg);
186 
187 	/*
188 	 * Just Removing each item from expired list And exp->enext will be
189 	 * intialized at next expire in this funtion.
190 	 */
191 	exp = exp->enext;
192       }
193     }
194   }
195 }
196 
197 void
198 timer_Show(int LogLevel, struct prompt *prompt)
199 {
200   struct pppTimer *pt;
201   int rest = 0;
202 
203 #define SECS(val)	((val) / SECTICKS)
204 #define HSECS(val)	(((val) % SECTICKS) * 100 / SECTICKS)
205 #define DISP								\
206   "%s timer[%p]: freq = %ld.%02lds, next = %d.%02ds, state = %s\n",	\
207   pt->name, pt, SECS(pt->load), HSECS(pt->load), SECS(rest),		\
208   HSECS(rest), tState2Nam(pt->state)
209 
210   if (!prompt)
211     log_Printf(LogLevel, "---- Begin of Timer Service List---\n");
212 
213   for (pt = TimerList; pt; pt = pt->next) {
214     rest += pt->rest;
215     if (prompt)
216       prompt_Printf(prompt, DISP);
217     else
218       log_Printf(LogLevel, DISP);
219   }
220 
221   if (!prompt)
222     log_Printf(LogLevel, "---- End of Timer Service List ---\n");
223 }
224 
225 void
226 timer_InitService()
227 {
228   struct itimerval itimer;
229 
230   sig_signal(SIGALRM, (void (*) (int)) TimerService);
231   itimer.it_interval.tv_sec = itimer.it_value.tv_sec = 0;
232   itimer.it_interval.tv_usec = itimer.it_value.tv_usec = TICKUNIT;
233   if (setitimer(ITIMER_REAL, &itimer, NULL) == -1)
234     log_Printf(LogERROR, "Unable to set itimer.\n");
235 }
236 
237 void
238 timer_TermService(void)
239 {
240   struct itimerval itimer;
241 
242   itimer.it_interval.tv_usec = itimer.it_interval.tv_sec = 0;
243   itimer.it_value.tv_usec = itimer.it_value.tv_sec = 0;
244   if (setitimer(ITIMER_REAL, &itimer, NULL) == -1)
245     log_Printf(LogERROR, "Unable to set itimer.\n");
246   sig_signal(SIGALRM, SIG_IGN);
247 }
248