freebsd-dev/contrib/sendmail/libsm/clock.c
Gregory Neil Shapiro 4e4196cb74 Import sendmail 8.13.6
Security:       FreeBSD-SA-06:13.sendmail
2006-03-22 16:40:03 +00:00

641 lines
14 KiB
C

/*
* Copyright (c) 1998-2004 Sendmail, Inc. and its suppliers.
* All rights reserved.
* Copyright (c) 1983, 1995-1997 Eric P. Allman. All rights reserved.
* Copyright (c) 1988, 1993
* The Regents of the University of California. All rights reserved.
*
* By using this file, you agree to the terms and conditions set
* forth in the LICENSE file which can be found at the top level of
* the sendmail distribution.
*
*/
#include <sm/gen.h>
SM_RCSID("@(#)$Id: clock.c,v 1.47 2005/06/14 23:07:20 ca Exp $")
#include <unistd.h>
#include <time.h>
#include <errno.h>
#if SM_CONF_SETITIMER
# include <sm/time.h>
#endif /* SM_CONF_SETITIMER */
#include <sm/heap.h>
#include <sm/debug.h>
#include <sm/bitops.h>
#include <sm/clock.h>
#include "local.h"
#if _FFR_SLEEP_USE_SELECT > 0
# include <sys/types.h>
#endif /* _FFR_SLEEP_USE_SELECT > 0 */
#if defined(_FFR_MAX_SLEEP_TIME) && _FFR_MAX_SLEEP_TIME > 2
# include <syslog.h>
#endif /* defined(_FFR_MAX_SLEEP_TIME) && _FFR_MAX_SLEEP_TIME > 2 */
#ifndef sigmask
# define sigmask(s) (1 << ((s) - 1))
#endif /* ! sigmask */
/*
** SM_SETEVENTM -- set an event to happen at a specific time in milliseconds.
**
** Events are stored in a sorted list for fast processing.
** An event only applies to the process that set it.
** Source is #ifdef'd to work with older OS's that don't have setitimer()
** (that is, don't have a timer granularity less than 1 second).
**
** Parameters:
** intvl -- interval until next event occurs (milliseconds).
** func -- function to call on event.
** arg -- argument to func on event.
**
** Returns:
** On success returns the SM_EVENT entry created.
** On failure returns NULL.
**
** Side Effects:
** none.
*/
static SM_EVENT *volatile SmEventQueue; /* head of event queue */
static SM_EVENT *volatile SmFreeEventList; /* list of free events */
SM_EVENT *
sm_seteventm(intvl, func, arg)
int intvl;
void (*func)__P((int));
int arg;
{
ENTER_CRITICAL();
if (SmFreeEventList == NULL)
{
SmFreeEventList = (SM_EVENT *) sm_pmalloc_x(sizeof *SmFreeEventList);
SmFreeEventList->ev_link = NULL;
}
LEAVE_CRITICAL();
return sm_sigsafe_seteventm(intvl, func, arg);
}
/*
** NOTE: THIS CAN BE CALLED FROM A SIGNAL HANDLER. DO NOT ADD
** ANYTHING TO THIS ROUTINE UNLESS YOU KNOW WHAT YOU ARE
** DOING.
*/
SM_EVENT *
sm_sigsafe_seteventm(intvl, func, arg)
int intvl;
void (*func)__P((int));
int arg;
{
register SM_EVENT **evp;
register SM_EVENT *ev;
#if SM_CONF_SETITIMER
auto struct timeval now, nowi, ival;
auto struct itimerval itime;
#else /* SM_CONF_SETITIMER */
auto time_t now, nowi;
#endif /* SM_CONF_SETITIMER */
int wasblocked;
/* negative times are not allowed */
if (intvl <= 0)
return NULL;
wasblocked = sm_blocksignal(SIGALRM);
#if SM_CONF_SETITIMER
ival.tv_sec = intvl / 1000;
ival.tv_usec = (intvl - ival.tv_sec * 1000) * 10;
(void) gettimeofday(&now, NULL);
nowi = now;
timeradd(&now, &ival, &nowi);
#else /* SM_CONF_SETITIMER */
now = time(NULL);
nowi = now + (time_t)(intvl / 1000);
#endif /* SM_CONF_SETITIMER */
/* search event queue for correct position */
for (evp = (SM_EVENT **) (&SmEventQueue);
(ev = *evp) != NULL;
evp = &ev->ev_link)
{
#if SM_CONF_SETITIMER
if (timercmp(&(ev->ev_time), &nowi, >=))
#else /* SM_CONF_SETITIMER */
if (ev->ev_time >= nowi)
#endif /* SM_CONF_SETITIMER */
break;
}
ENTER_CRITICAL();
if (SmFreeEventList == NULL)
{
/*
** This shouldn't happen. If called from sm_seteventm(),
** we have just malloced a SmFreeEventList entry. If
** called from a signal handler, it should have been
** from an existing event which sm_tick() just added to
** SmFreeEventList.
*/
LEAVE_CRITICAL();
if (wasblocked == 0)
(void) sm_releasesignal(SIGALRM);
return NULL;
}
else
{
ev = SmFreeEventList;
SmFreeEventList = ev->ev_link;
}
LEAVE_CRITICAL();
/* insert new event */
ev->ev_time = nowi;
ev->ev_func = func;
ev->ev_arg = arg;
ev->ev_pid = getpid();
ENTER_CRITICAL();
ev->ev_link = *evp;
*evp = ev;
LEAVE_CRITICAL();
(void) sm_signal(SIGALRM, sm_tick);
# if SM_CONF_SETITIMER
timersub(&SmEventQueue->ev_time, &now, &itime.it_value);
itime.it_interval.tv_sec = 0;
itime.it_interval.tv_usec = 0;
if (itime.it_value.tv_sec < 0)
itime.it_value.tv_sec = 0;
if (itime.it_value.tv_sec == 0 && itime.it_value.tv_usec == 0)
itime.it_value.tv_usec = 1000;
(void) setitimer(ITIMER_REAL, &itime, NULL);
# else /* SM_CONF_SETITIMER */
intvl = SmEventQueue->ev_time - now;
(void) alarm((unsigned) (intvl < 1 ? 1 : intvl));
# endif /* SM_CONF_SETITIMER */
if (wasblocked == 0)
(void) sm_releasesignal(SIGALRM);
return ev;
}
/*
** SM_CLREVENT -- remove an event from the event queue.
**
** Parameters:
** ev -- pointer to event to remove.
**
** Returns:
** none.
**
** Side Effects:
** arranges for event ev to not happen.
*/
void
sm_clrevent(ev)
register SM_EVENT *ev;
{
register SM_EVENT **evp;
int wasblocked;
# if SM_CONF_SETITIMER
struct itimerval clr;
# endif /* SM_CONF_SETITIMER */
if (ev == NULL)
return;
/* find the parent event */
wasblocked = sm_blocksignal(SIGALRM);
for (evp = (SM_EVENT **) (&SmEventQueue);
*evp != NULL;
evp = &(*evp)->ev_link)
{
if (*evp == ev)
break;
}
/* now remove it */
if (*evp != NULL)
{
ENTER_CRITICAL();
*evp = ev->ev_link;
ev->ev_link = SmFreeEventList;
SmFreeEventList = ev;
LEAVE_CRITICAL();
}
/* restore clocks and pick up anything spare */
if (wasblocked == 0)
(void) sm_releasesignal(SIGALRM);
if (SmEventQueue != NULL)
(void) kill(getpid(), SIGALRM);
else
{
/* nothing left in event queue, no need for an alarm */
# if SM_CONF_SETITIMER
clr.it_interval.tv_sec = 0;
clr.it_interval.tv_usec = 0;
clr.it_value.tv_sec = 0;
clr.it_value.tv_usec = 0;
(void) setitimer(ITIMER_REAL, &clr, NULL);
# else /* SM_CONF_SETITIMER */
(void) alarm(0);
# endif /* SM_CONF_SETITIMER */
}
}
/*
** SM_CLEAR_EVENTS -- remove all events from the event queue.
**
** Parameters:
** none.
**
** Returns:
** none.
*/
void
sm_clear_events()
{
register SM_EVENT *ev;
#if SM_CONF_SETITIMER
struct itimerval clr;
#endif /* SM_CONF_SETITIMER */
int wasblocked;
/* nothing will be left in event queue, no need for an alarm */
#if SM_CONF_SETITIMER
clr.it_interval.tv_sec = 0;
clr.it_interval.tv_usec = 0;
clr.it_value.tv_sec = 0;
clr.it_value.tv_usec = 0;
(void) setitimer(ITIMER_REAL, &clr, NULL);
#else /* SM_CONF_SETITIMER */
(void) alarm(0);
#endif /* SM_CONF_SETITIMER */
if (SmEventQueue == NULL)
return;
wasblocked = sm_blocksignal(SIGALRM);
/* find the end of the EventQueue */
for (ev = SmEventQueue; ev->ev_link != NULL; ev = ev->ev_link)
continue;
ENTER_CRITICAL();
ev->ev_link = SmFreeEventList;
SmFreeEventList = SmEventQueue;
SmEventQueue = NULL;
LEAVE_CRITICAL();
/* restore clocks and pick up anything spare */
if (wasblocked == 0)
(void) sm_releasesignal(SIGALRM);
}
/*
** SM_TICK -- take a clock tick
**
** Called by the alarm clock. This routine runs events as needed.
** Always called as a signal handler, so we assume that SIGALRM
** has been blocked.
**
** Parameters:
** One that is ignored; for compatibility with signal handlers.
**
** Returns:
** none.
**
** Side Effects:
** calls the next function in EventQueue.
**
** NOTE: THIS CAN BE CALLED FROM A SIGNAL HANDLER. DO NOT ADD
** ANYTHING TO THIS ROUTINE UNLESS YOU KNOW WHAT YOU ARE
** DOING.
*/
/* ARGSUSED */
SIGFUNC_DECL
sm_tick(sig)
int sig;
{
register SM_EVENT *ev;
pid_t mypid;
int save_errno = errno;
#if SM_CONF_SETITIMER
struct itimerval clr;
struct timeval now;
#else /* SM_CONF_SETITIMER */
register time_t now;
#endif /* SM_CONF_SETITIMER */
#if SM_CONF_SETITIMER
clr.it_interval.tv_sec = 0;
clr.it_interval.tv_usec = 0;
clr.it_value.tv_sec = 0;
clr.it_value.tv_usec = 0;
(void) setitimer(ITIMER_REAL, &clr, NULL);
gettimeofday(&now, NULL);
#else /* SM_CONF_SETITIMER */
(void) alarm(0);
now = time(NULL);
#endif /* SM_CONF_SETITIMER */
FIX_SYSV_SIGNAL(sig, sm_tick);
errno = save_errno;
CHECK_CRITICAL(sig);
mypid = getpid();
while (PendingSignal != 0)
{
int sigbit = 0;
int sig = 0;
if (bitset(PEND_SIGHUP, PendingSignal))
{
sigbit = PEND_SIGHUP;
sig = SIGHUP;
}
else if (bitset(PEND_SIGINT, PendingSignal))
{
sigbit = PEND_SIGINT;
sig = SIGINT;
}
else if (bitset(PEND_SIGTERM, PendingSignal))
{
sigbit = PEND_SIGTERM;
sig = SIGTERM;
}
else if (bitset(PEND_SIGUSR1, PendingSignal))
{
sigbit = PEND_SIGUSR1;
sig = SIGUSR1;
}
else
{
/* If we get here, we are in trouble */
abort();
}
PendingSignal &= ~sigbit;
kill(mypid, sig);
}
#if SM_CONF_SETITIMER
gettimeofday(&now, NULL);
#else /* SM_CONF_SETITIMER */
now = time(NULL);
#endif /* SM_CONF_SETITIMER */
while ((ev = SmEventQueue) != NULL &&
(ev->ev_pid != mypid ||
#if SM_CONF_SETITIMER
timercmp(&ev->ev_time, &now, <=)
#else /* SM_CONF_SETITIMER */
ev->ev_time <= now
#endif /* SM_CONF_SETITIMER */
))
{
void (*f)__P((int));
int arg;
pid_t pid;
/* process the event on the top of the queue */
ev = SmEventQueue;
SmEventQueue = SmEventQueue->ev_link;
/* we must be careful in here because ev_func may not return */
f = ev->ev_func;
arg = ev->ev_arg;
pid = ev->ev_pid;
ENTER_CRITICAL();
ev->ev_link = SmFreeEventList;
SmFreeEventList = ev;
LEAVE_CRITICAL();
if (pid != getpid())
continue;
if (SmEventQueue != NULL)
{
#if SM_CONF_SETITIMER
if (timercmp(&SmEventQueue->ev_time, &now, >))
{
timersub(&SmEventQueue->ev_time, &now,
&clr.it_value);
clr.it_interval.tv_sec = 0;
clr.it_interval.tv_usec = 0;
if (clr.it_value.tv_sec < 0)
clr.it_value.tv_sec = 0;
if (clr.it_value.tv_sec == 0 &&
clr.it_value.tv_usec == 0)
clr.it_value.tv_usec = 1000;
(void) setitimer(ITIMER_REAL, &clr, NULL);
}
else
{
clr.it_interval.tv_sec = 0;
clr.it_interval.tv_usec = 0;
clr.it_value.tv_sec = 3;
clr.it_value.tv_usec = 0;
(void) setitimer(ITIMER_REAL, &clr, NULL);
}
#else /* SM_CONF_SETITIMER */
if (SmEventQueue->ev_time > now)
(void) alarm((unsigned) (SmEventQueue->ev_time
- now));
else
(void) alarm(3);
#endif /* SM_CONF_SETITIMER */
}
/* call ev_func */
errno = save_errno;
(*f)(arg);
#if SM_CONF_SETITIMER
clr.it_interval.tv_sec = 0;
clr.it_interval.tv_usec = 0;
clr.it_value.tv_sec = 0;
clr.it_value.tv_usec = 0;
(void) setitimer(ITIMER_REAL, &clr, NULL);
gettimeofday(&now, NULL);
#else /* SM_CONF_SETITIMER */
(void) alarm(0);
now = time(NULL);
#endif /* SM_CONF_SETITIMER */
}
if (SmEventQueue != NULL)
{
#if SM_CONF_SETITIMER
timersub(&SmEventQueue->ev_time, &now, &clr.it_value);
clr.it_interval.tv_sec = 0;
clr.it_interval.tv_usec = 0;
if (clr.it_value.tv_sec < 0)
clr.it_value.tv_sec = 0;
if (clr.it_value.tv_sec == 0 && clr.it_value.tv_usec == 0)
clr.it_value.tv_usec = 1000;
(void) setitimer(ITIMER_REAL, &clr, NULL);
#else /* SM_CONF_SETITIMER */
(void) alarm((unsigned) (SmEventQueue->ev_time - now));
#endif /* SM_CONF_SETITIMER */
}
errno = save_errno;
return SIGFUNC_RETURN;
}
/*
** SLEEP -- a version of sleep that works with this stuff
**
** Because Unix sleep uses the alarm facility, I must reimplement
** it here.
**
** Parameters:
** intvl -- time to sleep.
**
** Returns:
** zero.
**
** Side Effects:
** waits for intvl time. However, other events can
** be run during that interval.
*/
# if !HAVE_NANOSLEEP
static void sm_endsleep __P((int));
static bool volatile SmSleepDone;
# endif /* !HAVE_NANOSLEEP */
#ifndef SLEEP_T
# define SLEEP_T unsigned int
#endif /* ! SLEEP_T */
SLEEP_T
sleep(intvl)
unsigned int intvl;
{
#if HAVE_NANOSLEEP
struct timespec rqtp;
if (intvl == 0)
return (SLEEP_T) 0;
rqtp.tv_sec = intvl;
rqtp.tv_nsec = 0;
nanosleep(&rqtp, NULL);
return (SLEEP_T) 0;
#else /* HAVE_NANOSLEEP */
int was_held;
SM_EVENT *ev;
#if _FFR_SLEEP_USE_SELECT > 0
int r;
# if _FFR_SLEEP_USE_SELECT > 0
struct timeval sm_io_to;
# endif /* _FFR_SLEEP_USE_SELECT > 0 */
#endif /* _FFR_SLEEP_USE_SELECT > 0 */
#if SM_CONF_SETITIMER
struct timeval now, begin, diff;
# if _FFR_SLEEP_USE_SELECT > 0
struct timeval slpv;
# endif /* _FFR_SLEEP_USE_SELECT > 0 */
#else /* SM_CONF_SETITIMER */
time_t begin, now;
#endif /* SM_CONF_SETITIMER */
if (intvl == 0)
return (SLEEP_T) 0;
#if defined(_FFR_MAX_SLEEP_TIME) && _FFR_MAX_SLEEP_TIME > 2
if (intvl > _FFR_MAX_SLEEP_TIME)
{
syslog(LOG_ERR, "sleep: interval=%u exceeds max value %d",
intvl, _FFR_MAX_SLEEP_TIME);
# if 0
SM_ASSERT(intvl < (unsigned int) INT_MAX);
# endif /* 0 */
intvl = _FFR_MAX_SLEEP_TIME;
}
#endif /* defined(_FFR_MAX_SLEEP_TIME) && _FFR_MAX_SLEEP_TIME > 2 */
SmSleepDone = false;
#if SM_CONF_SETITIMER
# if _FFR_SLEEP_USE_SELECT > 0
slpv.tv_sec = intvl;
slpv.tv_usec = 0;
# endif /* _FFR_SLEEP_USE_SELECT > 0 */
(void) gettimeofday(&now, NULL);
begin = now;
#else /* SM_CONF_SETITIMER */
now = begin = time(NULL);
#endif /* SM_CONF_SETITIMER */
ev = sm_setevent((time_t) intvl, sm_endsleep, 0);
if (ev == NULL)
{
/* COMPLAIN */
#if 0
syslog(LOG_ERR, "sleep: sm_setevent(%u) failed", intvl);
#endif /* 0 */
SmSleepDone = true;
}
was_held = sm_releasesignal(SIGALRM);
while (!SmSleepDone)
{
#if SM_CONF_SETITIMER
(void) gettimeofday(&now, NULL);
timersub(&now, &begin, &diff);
if (diff.tv_sec < 0 ||
(diff.tv_sec == 0 && diff.tv_usec == 0))
break;
# if _FFR_SLEEP_USE_SELECT > 0
timersub(&slpv, &diff, &sm_io_to);
# endif /* _FFR_SLEEP_USE_SELECT > 0 */
#else /* SM_CONF_SETITIMER */
now = time(NULL);
/*
** Check whether time expired before signal is released.
** Due to the granularity of time() add 1 to be on the
** safe side.
*/
if (!(begin + (time_t) intvl + 1 > now))
break;
# if _FFR_SLEEP_USE_SELECT > 0
sm_io_to.tv_sec = intvl - (now - begin);
if (sm_io_to.tv_sec <= 0)
sm_io_to.tv_sec = 1;
sm_io_to.tv_usec = 0;
# endif /* _FFR_SLEEP_USE_SELECT > 0 */
#endif /* SM_CONF_SETITIMER */
#if _FFR_SLEEP_USE_SELECT > 0
if (intvl <= _FFR_SLEEP_USE_SELECT)
{
r = select(0, NULL, NULL, NULL, &sm_io_to);
if (r == 0)
break;
}
else
#endif /* _FFR_SLEEP_USE_SELECT > 0 */
(void) pause();
}
/* if out of the loop without the event being triggered remove it */
if (!SmSleepDone)
sm_clrevent(ev);
if (was_held > 0)
(void) sm_blocksignal(SIGALRM);
return (SLEEP_T) 0;
#endif /* HAVE_NANOSLEEP */
}
#if !HAVE_NANOSLEEP
static void
sm_endsleep(ignore)
int ignore;
{
/*
** NOTE: THIS CAN BE CALLED FROM A SIGNAL HANDLER. DO NOT ADD
** ANYTHING TO THIS ROUTINE UNLESS YOU KNOW WHAT YOU ARE
** DOING.
*/
SmSleepDone = true;
}
#endif /* !HAVE_NANOSLEEP */