s-s-d: Use system timersub and fix timeval normalization in multiplication

Closes: #462225

ChangeLog

@@ -1,3 +1,9 @@
+2008-01-25  Andreas Påhlsson  <andreas.pahlsson@xcerion.com>
+
+	* utils/start-stop-daemon.c (tsub): Remove function.
+	(tmul): Fix normalization.
+	(run_stop_schedule): Use timersub instead of tsub.
+
 2008-01-24  Raphael Hertzog  <hertzog@debian.org>
 
 	* scripts/dpkg-genchanges.pl: Warn if the current version is

THANKS

@@ -6,6 +6,7 @@ Alberto Garcia <berto@gpul.org>
 Anand Kumria <wildfire@progsoc.org>
 Andreas Barth <aba@not.so.argh.org>
 Andreas Metzler <ametzler@debian.org>
+Andreas Påhlsson <andreas.pahlsson@xcerion.com>
 Andrew Ferrier <andrew@new-destiny.co.uk>
 Andrew Hobson <ahobson@eng.mindspring.net>
 Andrew Suffield <asuffield@debian.org>

debian/changelog

@@ -6,6 +6,8 @@ dpkg (1.14.17) UNRELEASED; urgency=low
   * Add new keybinding in dselect to restore all selections back to
     whatever's currently installed. Closes: #151540
     Thanks to Colin Watson.
+  * Use system timersub and fix timeval normalization in multiplication in
+    start-stop-daemon. Thanks to Andreas Påhlsson. Closes: #462225
 
   [ Raphael Hertzog ]
   * Add a warning displayed by dpkg-genchanges if the current version is

utils/start-stop-daemon.c

@@ -216,26 +216,13 @@ xgettimeofday(struct timeval *tv)
 		fatal("gettimeofday failed: %s", strerror(errno));
 }
 
-static void
-tsub(struct timeval *r, struct timeval *a, struct timeval *b)
-{
-	r->tv_sec = (time_t)(a->tv_sec - b->tv_sec);
-	r->tv_usec = (suseconds_t)(a->tv_usec - b->tv_usec);
-	if (r->tv_usec < 0) {
-		--r->tv_sec;
-		r->tv_usec += 1000000;
-	}
-}
-
 static void
 tmul(struct timeval *a, int b)
 {
 	a->tv_sec *= b;
 	a->tv_usec *= b;
-	if (a->tv_usec >= 1000000) {
-		++a->tv_sec;
-		a->tv_usec -= 1000000;
-	}
+	a->tv_sec = a->tv_sec + a->tv_usec / 1000000;
+	a->tv_usec %= 1000000;
 }
 
 static long
@@ -1200,8 +1187,8 @@ run_stop_schedule(void)
 				if (ratio < 10)
 					ratio++;
 
-				tsub(&maxinterval, &stopat, &after);
-				tsub(&interval, &after, &before);
+				timersub(&stopat, &after, &maxinterval);
+				timersub(&after, &before, &interval);
 				tmul(&interval, ratio);
 
 				if (interval.tv_sec < 0 || interval.tv_usec < 0)