freebsd-dev/usr.sbin/ppp/timer.c
Andrey A. Chernov ee5f208d63 Don't pend SIGALRM (Timer Service) due to
1) When carrier dropped, old variant often forget to detect it cause
unkillable loop forever (because SIGTERM pended too, but it will be
separate commit)
2) Time intervals accuracy reasons

Should go into 2.2
1997-03-08 09:55:42 +00:00

293 lines
6.5 KiB
C

/*
* PPP Timer Processing Module
*
* Written by Toshiharu OHNO (tony-o@iij.ad.jp)
*
* Copyright (C) 1993, Internet Initiative Japan, Inc. All rights reserverd.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by the Internet Initiative Japan, Inc. The name of the
* IIJ may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*
* $Id: timer.c,v 1.10 1997/02/25 14:05:17 brian Exp $
*
* TODO:
*/
#include "defs.h"
#include <sys/time.h>
#include <signal.h>
#include "timeout.h"
#include <sys/cdefs.h>
#include "sig.h"
#ifdef SIGALRM
#include <errno.h>
#endif
void StopTimerNoBlock( struct pppTimer *);
void ShowTimers(void);
void
StopTimer( struct pppTimer *tp )
{
#ifdef SIGALRM
int omask;
omask = sigblock(sigmask(SIGALRM));
#endif
StopTimerNoBlock(tp);
#ifdef SIGALRM
sigsetmask(omask);
#endif
}
void
StartTimer(tp)
struct pppTimer *tp;
{
struct pppTimer *t, *pt;
u_long ticks = 0;
#ifdef SIGALRM
int omask;
omask = sigblock(sigmask(SIGALRM));
#endif
if (tp->state != TIMER_STOPPED) {
StopTimerNoBlock(tp);
}
if (tp->load == 0) {
#ifdef DEBUG
logprintf("timer %x has 0 load!\n", tp);
#endif
sigsetmask(omask);
return;
}
pt = NULL;
for (t = TimerList; t; t = t->next) {
#ifdef DEBUG
logprintf("StartTimer: %x(%d): ticks: %d, rest: %d\n", t, t->state, ticks, t->rest);
#endif
if (ticks + t->rest >= tp->load)
break;
ticks += t->rest;
pt = t;
}
tp->state = TIMER_RUNNING;
tp->rest = tp->load - ticks;
#ifdef DEBUG
logprintf("Inserting %x before %x, rest = %d\n", tp, t, tp->rest);
#endif
/* Insert given *tp just before *t */
tp->next = t;
if (pt) {
pt->next = tp;
} else {
InitTimerService();
TimerList = tp;
}
if (t)
t->rest -= tp->rest;
#ifdef SIGALRM
sigsetmask(omask);
#endif
}
void
StopTimerNoBlock(tp)
struct pppTimer *tp;
{
struct pppTimer *t, *pt;
/*
* A Running Timer should be removing TimerList,
* But STOPPED/EXPIRED is already removing TimerList.
* So just marked as TIMER_STOPPED.
* Do not change tp->enext!! (Might be Called by expired proc)
*/
#ifdef DEBUG
logprintf("StopTimer: %x, next = %x state=%x\n", tp, tp->next, tp->state);
#endif
if (tp->state != TIMER_RUNNING) {
tp->next = NULL;
tp->state = TIMER_STOPPED;
return;
}
pt = NULL;
for (t = TimerList; t != tp && t !=NULL ; t = t->next)
pt = t;
if (t) {
if (pt) {
pt->next = t->next;
} else {
TimerList = t->next;
if ( TimerList == NULL ) /* Last one ? */
TermTimerService(); /* Terminate Timer Service */
}
if (t->next)
t->next->rest += tp->rest;
} else {
logprintf("Oops, timer not found!!\n");
}
tp->next = NULL;
tp->state = TIMER_STOPPED;
}
void
TimerService()
{
struct pppTimer *tp, *exp, *wt;
#ifdef DEBUG
ShowTimers();
#endif
tp = TimerList;
if (tp) {
tp->rest--;
if (tp->rest == 0) {
/*
* Multiple timers may expires at once. Create list of expired timers.
*/
exp = NULL;
do {
tp->state = TIMER_EXPIRED;
wt = tp->next;
tp->enext = exp;
exp = tp;
#ifdef DEBUG
logprintf("Add %x to exp\n", tp);
#endif
tp = wt;
} while (tp && (tp->rest == 0));
TimerList = tp;
if ( TimerList == NULL ) /* No timers ? */
TermTimerService(); /* Terminate Timer Service */
#ifdef DEBUG
logprintf("TimerService: next is %x(%d)\n",
TimerList, TimerList? TimerList->rest : 0);
#endif
/*
* Process all expired timers.
*/
while (exp) {
#ifdef notdef
StopTimer(exp);
#endif
if (exp->func)
(*exp->func)(exp->arg);
/*
* Just Removing each item from expired list
* And exp->enext will be intialized at next expire
* in this funtion.
*/
exp = exp->enext;
}
}
}
}
void
ShowTimers()
{
struct pppTimer *pt;
logprintf("---- Begin of Timer Service List---\n");
for (pt = TimerList; pt; pt = pt->next)
logprintf("%x: load = %d, rest = %d, state =%x\n",
pt, pt->load, pt->rest, pt->state);
logprintf("---- End of Timer Service List ---\n");
}
#ifdef SIGALRM
u_int
sleep( u_int sec )
{
struct timeval to,st,et;
long sld, nwd, std;
gettimeofday( &st, NULL );
to.tv_sec = sec;
to.tv_usec = 0;
std = st.tv_sec * 1000000 + st.tv_usec;
for (;;) {
if ( select ( 0, NULL, NULL, NULL, &to) == 0 ||
errno != EINTR ) {
break;
} else {
gettimeofday( &et, NULL );
sld = to.tv_sec * 1000000 + to.tv_sec;
nwd = et.tv_sec * 1000000 + et.tv_usec - std;
if ( sld > nwd )
sld -= nwd;
else
sld = 1; /* Avoid both tv_sec/usec is 0 */
/* Calculate timeout value for select */
to.tv_sec = sld / 1000000;
to.tv_usec = sld % 1000000;
}
}
return (0L);
}
void usleep( u_int usec)
{
struct timeval to,st,et;
long sld, nwd, std;
gettimeofday( &st, NULL );
to.tv_sec = 0;
to.tv_usec = usec;
std = st.tv_sec * 1000000 + st.tv_usec;
for (;;) {
if ( select ( 0, NULL, NULL, NULL, &to) == 0 ||
errno != EINTR ) {
break;
} else {
gettimeofday( &et, NULL );
sld = to.tv_sec * 1000000 + to.tv_sec;
nwd = et.tv_sec * 1000000 + et.tv_usec - std;
if ( sld > nwd )
sld -= nwd;
else
sld = 1; /* Avoid both tv_sec/usec is 0 */
/* Calculate timeout value for select */
to.tv_sec = sld / 1000000;
to.tv_usec = sld % 1000000;
}
}
}
void InitTimerService( void ) {
struct itimerval itimer;
signal(SIGALRM, (void (*)(int))TimerService);
itimer.it_interval.tv_sec = itimer.it_value.tv_sec = 0;
itimer.it_interval.tv_usec = itimer.it_value.tv_usec = TICKUNIT;
setitimer(ITIMER_REAL, &itimer, NULL);
}
void TermTimerService( void ) {
struct itimerval itimer;
itimer.it_interval.tv_sec = itimer.it_value.tv_sec = 0;
itimer.it_value.tv_usec = itimer.it_value.tv_sec = 0;
setitimer(ITIMER_REAL, &itimer, NULL);
/*
* Notes: after disabling timer here, we will get one
* SIGALRM will be got.
*/
signal(SIGALRM, SIG_IGN);
}
#endif