Imported Upstream version 8.8.8upstream/8.8.8

1 files changed, 287 insertions, 0 deletions

diff --git a/src/clock.c b/src/clock.c
new file mode 100644
index 0000000..6940b29
--- /dev/null
+++ b/src/clock.c
@@ -0,0 +1,287 @@
+/*
+ * Copyright (c) 1983, 1995-1997 Eric P. Allman
+ * Copyright (c) 1988, 1993
+ *	The Regents of the University of California.  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.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
+ */
+
+#ifndef lint
+static char sccsid[] = "@(#)clock.c	8.24 (Berkeley) 4/19/97";
+#endif /* not lint */
+
+# include "sendmail.h"
+
+# ifndef sigmask
+#  define sigmask(s)	(1 << ((s) - 1))
+# endif
+
+/*
+**  SETEVENT -- set an event to happen at a specific time.
+**
+**	Events are stored in a sorted list for fast processing.
+**	An event only applies to the process that set it.
+**
+**	Parameters:
+**		intvl -- intvl until next event occurs.
+**		func -- function to call on event.
+**		arg -- argument to func on event.
+**
+**	Returns:
+**		none.
+**
+**	Side Effects:
+**		none.
+*/
+
+EVENT	*FreeEventList;		/* list of free events */
+
+static SIGFUNC_DECL	tick __P((int));
+
+EVENT *
+setevent(intvl, func, arg)
+	time_t intvl;
+	void (*func)();
+	int arg;
+{
+	register EVENT **evp;
+	register EVENT *ev;
+	auto time_t now;
+	int wasblocked;
+
+	if (intvl <= 0)
+	{
+		syserr("554 setevent: intvl=%ld\n", intvl);
+		return (NULL);
+	}
+
+	wasblocked = blocksignal(SIGALRM);
+	(void) time(&now);
+
+	/* search event queue for correct position */
+	for (evp = &EventQueue; (ev = *evp) != NULL; evp = &ev->ev_link)
+	{
+		if (ev->ev_time >= now + intvl)
+			break;
+	}
+
+	/* insert new event */
+	ev = FreeEventList;
+	if (ev == NULL)
+		ev = (EVENT *) xalloc(sizeof *ev);
+	else
+		FreeEventList = ev->ev_link;
+	ev->ev_time = now + intvl;
+	ev->ev_func = func;
+	ev->ev_arg = arg;
+	ev->ev_pid = getpid();
+	ev->ev_link = *evp;
+	*evp = ev;
+
+	if (tTd(5, 5))
+		printf("setevent: intvl=%ld, for=%ld, func=%lx, arg=%d, ev=%lx\n",
+			intvl, now + intvl, (u_long) func, arg, (u_long) ev);
+
+	setsignal(SIGALRM, tick);
+	intvl = EventQueue->ev_time - now;
+	(void) alarm((unsigned) intvl < 1 ? 1 : intvl);
+	if (wasblocked == 0)
+		(void) releasesignal(SIGALRM);
+	return (ev);
+}
+/*
+**  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
+clrevent(ev)
+	register EVENT *ev;
+{
+	register EVENT **evp;
+	int wasblocked;
+
+	if (tTd(5, 5))
+		printf("clrevent: ev=%lx\n", (u_long) ev);
+	if (ev == NULL)
+		return;
+
+	/* find the parent event */
+	wasblocked = blocksignal(SIGALRM);
+	for (evp = &EventQueue; *evp != NULL; evp = &(*evp)->ev_link)
+	{
+		if (*evp == ev)
+			break;
+	}
+
+	/* now remove it */
+	if (*evp != NULL)
+	{
+		*evp = ev->ev_link;
+		ev->ev_link = FreeEventList;
+		FreeEventList = ev;
+	}
+
+	/* restore clocks and pick up anything spare */
+	if (wasblocked == 0)
+		releasesignal(SIGALRM);
+	if (EventQueue != NULL)
+		kill(getpid(), SIGALRM);
+}
+/*
+**  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.
+*/
+
+static SIGFUNC_DECL
+tick(arg)
+	int arg;
+{
+	register time_t now;
+	register EVENT *ev;
+	int mypid = getpid();
+	int olderrno = errno;
+
+	(void) alarm(0);
+	now = curtime();
+
+	if (tTd(5, 4))
+		printf("tick: now=%ld\n", now);
+
+	/* reset signal in case System V semantics */
+	(void) setsignal(SIGALRM, tick);
+	while ((ev = EventQueue) != NULL &&
+	       (ev->ev_time <= now || ev->ev_pid != mypid))
+	{
+		void (*f)();
+		int arg;
+		int pid;
+
+		/* process the event on the top of the queue */
+		ev = EventQueue;
+		EventQueue = EventQueue->ev_link;
+		if (tTd(5, 6))
+			printf("tick: ev=%lx, func=%lx, arg=%d, pid=%d\n",
+				(u_long) ev, (u_long) ev->ev_func,
+				ev->ev_arg, ev->ev_pid);
+
+		/* we must be careful in here because ev_func may not return */
+		f = ev->ev_func;
+		arg = ev->ev_arg;
+		pid = ev->ev_pid;
+		ev->ev_link = FreeEventList;
+		FreeEventList = ev;
+		if (pid != getpid())
+			continue;
+		if (EventQueue != NULL)
+		{
+			if (EventQueue->ev_time > now)
+				(void) alarm((unsigned) (EventQueue->ev_time - now));
+			else
+				(void) alarm(3);
+		}
+
+		/* call ev_func */
+		errno = olderrno;
+		(*f)(arg);
+		(void) alarm(0);
+		now = curtime();
+	}
+	if (EventQueue != NULL)
+		(void) alarm((unsigned) (EventQueue->ev_time - now));
+	errno = olderrno;
+	return SIGFUNC_RETURN;
+}
+/*
+**  SLEEP -- a version of sleep that works with this stuff
+**
+**	Because sleep uses the alarm facility, I must reimplement
+**	it here.
+**
+**	Parameters:
+**		intvl -- time to sleep.
+**
+**	Returns:
+**		none.
+**
+**	Side Effects:
+**		waits for intvl time.  However, other events can
+**		be run during that interval.
+*/
+
+static bool	SleepDone;
+static void	endsleep();
+
+#ifndef SLEEP_T
+# define SLEEP_T	unsigned int
+#endif
+
+SLEEP_T
+sleep(intvl)
+	unsigned int intvl;
+{
+	int was_held;
+
+	if (intvl == 0)
+		return (SLEEP_T) 0;
+	SleepDone = FALSE;
+	(void) setevent((time_t) intvl, endsleep, 0);
+	was_held = releasesignal(SIGALRM);
+	while (!SleepDone)
+		pause();
+	if (was_held > 0)
+		blocksignal(SIGALRM);
+	return (SLEEP_T) 0;
+}
+
+static void
+endsleep()
+{
+	SleepDone = TRUE;
+}