replace chronyd with sntpc, sync every 15s not 15m

Signed-off-by: Justin Cormack <justin.cormack@docker.com>

alpine/Dockerfile

@@ -9,7 +9,7 @@ RUN \
   apk update && apk upgrade && \
   apk add \
   e2fsprogs \
-  chrony \
+  sntpc \
   git \
   xz \
   iptables \
@@ -62,7 +62,7 @@ COPY packages/hvtools/hv_get_dhcp_info /sbin/
 COPY packages/hvtools/hv_get_dns_info /sbin/
 COPY packages/hvtools/hv_set_ifconfig /sbin/
 COPY packages/hvtools/hvtools.tar.gz /usr/share/src/
-COPY packages/chronyd/etc /etc/
+COPY packages/sntpc/etc /etc/
 COPY packages/userns/etc /etc/
 COPY packages/userns/groupadd /usr/sbin
 COPY packages/userns/useradd /usr/sbin
@@ -82,7 +82,7 @@ RUN \
   rc-update add syslog boot && \
   rc-update add networking boot && \
   rc-update add acpid default && \
-  rc-update add chronyd default && \
+  rc-update add sntpc default && \
   rc-update add cron default && \
   rc-update add savecache shutdown && \
   rc-update add killprocs shutdown && \

alpine/packages/chronyd/etc/init.d/chronyd

@@ -1,73 +0,0 @@
-#!/sbin/openrc-run
-# Copyright 1999-2007 Gentoo Foundation
-# Distributed under the terms of the GNU General Public License v2
-# $Header: /var/cvsroot/gentoo-x86/net-misc/chrony/files/chronyd.rc,v 1.8 2007/03/22 14:32:09 tove Exp $
-
-description="NTP daemon"
-
-depend() {
-	need net
-	after firewall
-	provide ntp-client ntp-server
-	use dns
-}
-
-checkconfig() {
-	# Note that /etc/chrony/chrony.keys is *NOT* checked. This
-	# is because the user may have specified another key
-	# file, and we don't want to force the user to use that
-	# exact name for the key file.
-	if [ ! -f "${CFGFILE}" ] ; then
-		eerror "Please create ${CFGFILE} and the"
-		eerror "chrony key file (usually /etc/chrony/chrony.keys)"
-		eerror "by using the"
-		eerror ""
-		eerror "        chrony.conf.example"
-		eerror "        chrony.keys.example"
-		eerror ""
-		eerror "files (from the documentation directory)"
-		eerror "as templates."
-		return 1
-	else
-		# Actually, I tried it, and chrony seems to ignore the pidfile
-		# option. I'm going to leave it here anyway, since you never
-		# know if it might be handy
-		PIDFILE=`awk '/^ *pidfile/{print $2}' "${CFGFILE}"`
-	fi
-	return 0
-}
-
-setxtrarg() {
-	if [ -c /dev/rtc ]; then
-		grep -q '^rtcfile' "${CFGFILE}" && ARGS="${ARGS} -s"
-	fi
-	grep -q '^dumponexit$' "${CFGFILE}" && ARGS="${ARGS} -r"
-	return 0
-}
-
-start() {
-	[ -d /sys/bus/vmbus ] && exit 0
-	checkconfig || return $?
-	setxtrarg
-
-	[ -n "${PIDFILE}" ] || PIDFILE=/var/run/chronyd.pid
-
-	ebegin "Starting chronyd"
-	start-stop-daemon --start --quiet \
-		--exec /usr/sbin/chronyd \
-		--pidfile "${PIDFILE}" \
-		-- -f "${CFGFILE}" ${ARGS}
-	eend $? "Failed to start chronyd"
-}
-
-stop() {
-	[ -d /sys/bus/vmbus ] && exit 0
-	checkconfig || return $?
-
-	[ -n "${PIDFILE}" ] || PIDFILE=/var/run/chronyd.pid
-
-	ebegin "Stopping chronyd"
-	start-stop-daemon --stop --quiet \
-		--pidfile "${PIDFILE}"
-	eend $? "Failed to stop chronyd"
-}

alpine/packages/docker/etc/init.d/docker

@@ -3,7 +3,6 @@
 depend()
 {
 	after transfused
-	before chronyd
 }
 
 start()

alpine/packages/sntpc/etc/conf.d/sntpc

@@ -0,0 +1,2 @@
+SNTPC_INTERVAL=15
+SNTPC_HOST=0.pool.ntp.org

alpine/packages/sntpc/etc/init.d/sntpc

@@ -0,0 +1,35 @@
+#!/sbin/openrc-run
+
+NAME=sntpc
+DAEMON=/usr/sbin/$NAME
+
+depend() {
+	need net
+	after firewall
+}
+
+start() {
+	# Windows has pvclock, not needed
+	[ -d /sys/bus/vmbus ] && exit 0
+
+	local msg opts
+	if [ "$SNTPC_INTERVAL" = "0" ]; then
+		msg="Setting time from NTP source"
+	else
+		msg="Starting ${NAME}"
+		opts="-d"
+	fi
+	ebegin "$msg"
+		start-stop-daemon --start --quiet --name sntpc \
+			--exec ${DAEMON} -- \
+			-i ${SNTPC_INTERVAL} $opts ${SNTPC_HOST}
+	eend $?
+}
+
+stop() {
+	[ -d /sys/bus/vmbus ] && exit 0
+	ebegin "Stopping ${NAME}"
+		start-stop-daemon --stop --quiet \
+			--exec ${DAEMON} 
+	eend $?
+}