From b7a4bed866ac70efc617789460edd340aef73114 Mon Sep 17 00:00:00 2001
From: hwdsl2 <hwdsl2@users.noreply.github.com>
Date: Mon, 30 Oct 2017 01:56:00 -0500
Subject: [PATCH] Improve startup

- Ubuntu 16.04 (and newer) may run apt tasks automatically on boot
- If used as a startup script, apt-get commands could fail due to this
- Wait for apt/dpkg lock (up to 60s) as a workaround
- Ref: #252
---
 vpnsetup.sh | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/vpnsetup.sh b/vpnsetup.sh
index 13d04b7..90f21e4 100755
--- a/vpnsetup.sh
+++ b/vpnsetup.sh
@@ -138,6 +138,14 @@ cd /opt/src || exiterr "Cannot enter /opt/src."
 
 bigecho "Populating apt-get cache..."
 
+count=0
+while fuser /var/lib/apt/lists/lock /var/lib/dpkg/lock >/dev/null 2>&1; do
+  [ "$count" -ge "20" ] && exiterr "Cannot get apt/dpkg lock."
+  count=$((count+1))
+  printf %s .
+  sleep 3
+done
+
 export DEBIAN_FRONTEND=noninteractive
 apt-get -yq update || exiterr "'apt-get update' failed."