From: Kenneth Johansson <kenneth.johansson@inteno.se>
Date: Wed, 24 May 2017 11:45:37 +0000 (+0200)
Subject: sysupgrade: run only one instance at a time.
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=e96a9a9af82c00dcce606a84a7bb87a00411385d;p=openwrt%2Fstaging%2Fzorun.git

sysupgrade: run only one instance at a time.

Things do not work well if running multiple instances of
upgrade at the same time.

Signed-off-by: Kenneth Johansson <kenneth.johansson@inteno.se>
---

diff --git a/package/base-files/files/sbin/sysupgrade b/package/base-files/files/sbin/sysupgrade
index c095ca81c5..1eede14b05 100755
--- a/package/base-files/files/sbin/sysupgrade
+++ b/package/base-files/files/sbin/sysupgrade
@@ -47,6 +47,20 @@ while [ -n "$1" ]; do
 	shift;
 done
 
+# just one instance
+if  ! lock -n /tmp/sysupgrade.lock
+then
+	echo "Another instance of sysupgrade already running"
+	echo "If you are sure this is wrong remove file /tmp/sysupgrade.lock"
+	exit 1
+fi
+
+# make sure the lock is removed when done even when killed
+finish() {
+	lock -u /var/sysupgrade.lock
+}
+trap finish EXIT INT TERM
+
 export CONFFILES=/tmp/sysupgrade.conffiles
 export CONF_TAR=/tmp/sysupgrade.tgz