FreeBSD-5.3/usr.sbin/ppp/timer.c
/*-
* Copyright (c) 1996 - 2001 Brian Somers <brian@Awfulhak.org>
* based on work by Toshiharu OHNO <tony-o@iij.ad.jp>
* Internet Initiative Japan, Inc (IIJ)
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD: src/usr.sbin/ppp/timer.c,v 1.47 2002/08/27 20:11:58 brian Exp $
*/
#include <errno.h>
#include <signal.h>
#include <stdarg.h>
#include <stdio.h>
#include <string.h>
#include <sys/time.h>
#include <termios.h>
#include "log.h"
#include "sig.h"
#include "timer.h"
#include "descriptor.h"
#include "prompt.h"
#define RESTVAL(t) \
((t).it_value.tv_sec * SECTICKS + (t).it_value.tv_usec / TICKUNIT + \
((((t).it_value.tv_usec % TICKUNIT) >= (TICKUNIT >> 1)) ? 1 : 0))
static struct pppTimer *TimerList = NULL, *ExpiredList = NULL;
static void StopTimerNoBlock(struct pppTimer *);
static const char *
tState2Nam(u_int state)
{
static const char * const StateNames[] = { "stopped", "running", "expired" };
if (state >= sizeof StateNames / sizeof StateNames[0])
return "unknown";
return StateNames[state];
}
void
timer_Stop(struct pppTimer *tp)
{
sigset_t mask, omask;
sigemptyset(&mask);
sigaddset(&mask, SIGALRM);
sigprocmask(SIG_BLOCK, &mask, &omask);
StopTimerNoBlock(tp);
sigprocmask(SIG_SETMASK, &omask, NULL);
}
void
timer_Start(struct pppTimer *tp)
{
struct itimerval itimer;
struct pppTimer *t, *pt;
u_long ticks = 0;
sigset_t mask, omask;
sigemptyset(&mask);
sigaddset(&mask, SIGALRM);
sigprocmask(SIG_BLOCK, &mask, &omask);
if (tp->state != TIMER_STOPPED)
StopTimerNoBlock(tp);
if (tp->load == 0) {
log_Printf(LogTIMER, "%s timer[%p] has 0 load!\n", tp->name, tp);
sigprocmask(SIG_SETMASK, &omask, NULL);
return;
}
/* Adjust our first delta so that it reflects what's really happening */
if (TimerList && getitimer(ITIMER_REAL, &itimer) == 0)
TimerList->rest = RESTVAL(itimer);
pt = NULL;
for (t = TimerList; t; t = t->next) {
if (ticks + t->rest >= tp->load)
break;
ticks += t->rest;
pt = t;
}
tp->state = TIMER_RUNNING;
tp->rest = tp->load - ticks;
if (t)
log_Printf(LogTIMER, "timer_Start: Inserting %s timer[%p] before %s "
"timer[%p], delta = %ld\n", tp->name, tp, t->name, t, tp->rest);
else
log_Printf(LogTIMER, "timer_Start: Inserting %s timer[%p]\n", tp->name, tp);
/* Insert given *tp just before *t */
tp->next = t;
if (pt) {
pt->next = tp;
} else {
TimerList = tp;
timer_InitService(t != NULL); /* [re]Start the Timer Service */
}
if (t)
t->rest -= tp->rest;
sigprocmask(SIG_SETMASK, &omask, NULL);
}
static void
StopTimerNoBlock(struct pppTimer *tp)
{
struct pppTimer *t, *pt;
/*
* A RUNNING timer must be removed from TimerList (->next list).
* A STOPPED timer isn't in any list, but may have a bogus [e]next field.
* An EXPIRED timer is in the ->enext list.
*/
if (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 ? */
timer_TermService(); /* Terminate Timer Service */
}
if (t->next) {
if (!pt) { /* t (tp) was the first in the list */
struct itimerval itimer;
if (getitimer(ITIMER_REAL, &itimer) == 0)
t->rest = RESTVAL(itimer);
}
t->next->rest += t->rest;
if (!pt) /* t->next is now the first in the list */
timer_InitService(1);
}
} else {
/* Search for any pending expired timers */
pt = NULL;
for (t = ExpiredList; t != tp && t != NULL; t = t->enext)
pt = t;
if (t) {
if (pt)
pt->enext = t->enext;
else
ExpiredList = t->enext;
} else if (tp->state == TIMER_RUNNING)
log_Printf(LogERROR, "Oops, %s timer not found!!\n", tp->name);
}
tp->next = tp->enext = NULL;
tp->state = TIMER_STOPPED;
}
static void
TimerService(void)
{
struct pppTimer *tp, *exp, *next;
if (log_IsKept(LogTIMER)) {
static time_t t; /* Only show timers globally every second */
time_t n = time(NULL);
if (n > t)
timer_Show(LogTIMER, NULL);
t = n;
}
tp = TimerList;
if (tp) {
tp->rest = 0;
/* Multiple timers might expire at once. Create a list of expired timers */
exp = NULL;
do {
tp->state = TIMER_EXPIRED;
next = tp->next;
tp->enext = exp;
exp = tp;
tp = next;
} while (tp && tp->rest == 0);
TimerList = tp;
if (TimerList != NULL) /* Any timers remaining ? */
timer_InitService(1); /* Restart the Timer Service */
else
timer_TermService(); /* Stop the Timer Service */
/* Process all expired timers */
while (exp) {
ExpiredList = exp->enext;
exp->enext = NULL;
if (exp->func)
(*exp->func)(exp->arg);
exp = ExpiredList;
}
}
}
void
timer_Show(int LogLevel, struct prompt *prompt)
{
struct itimerval itimer;
struct pppTimer *pt;
u_long rest = 0;
/* Adjust our first delta so that it reflects what's really happening */
if (TimerList && getitimer(ITIMER_REAL, &itimer) == 0)
TimerList->rest = RESTVAL(itimer);
#define SECS(val) ((val) / SECTICKS)
#define HSECS(val) (((val) % SECTICKS) * 100 / SECTICKS)
#define DISP \
"%s timer[%p]: freq = %ld.%02lds, next = %lu.%02lus, state = %s\n", \
pt->name, pt, SECS(pt->load), HSECS(pt->load), SECS(rest), \
HSECS(rest), tState2Nam(pt->state)
if (!prompt)
log_Printf(LogLevel, "---- Begin of Timer Service List---\n");
for (pt = TimerList; pt; pt = pt->next) {
rest += pt->rest;
if (prompt)
prompt_Printf(prompt, DISP);
else
log_Printf(LogLevel, DISP);
}
if (!prompt)
log_Printf(LogLevel, "---- End of Timer Service List ---\n");
}
void
timer_InitService(int restart)
{
struct itimerval itimer;
if (TimerList) {
if (!restart)
sig_signal(SIGALRM, (void (*)(int))TimerService);
itimer.it_interval.tv_sec = 0;
itimer.it_interval.tv_usec = 0;
itimer.it_value.tv_sec = TimerList->rest / SECTICKS;
itimer.it_value.tv_usec = (TimerList->rest % SECTICKS) * TICKUNIT;
if (setitimer(ITIMER_REAL, &itimer, NULL) == -1)
log_Printf(LogERROR, "Unable to set itimer (%s)\n", strerror(errno));
}
}
void
timer_TermService(void)
{
struct itimerval itimer;
itimer.it_interval.tv_usec = itimer.it_interval.tv_sec = 0;
itimer.it_value.tv_usec = itimer.it_value.tv_sec = 0;
if (setitimer(ITIMER_REAL, &itimer, NULL) == -1)
log_Printf(LogERROR, "Unable to set itimer (%s)\n", strerror(errno));
sig_signal(SIGALRM, SIG_IGN);
}