From f673b4f640315c19f73cc4147ce051a59e9504ff Mon Sep 17 00:00:00 2001
From: David Lamparter <equinox@diac24.net>
Date: Fri, 14 Dec 2018 22:43:39 +0100
Subject: [PATCH] debian: keep working nicely with split config

Drop our configs that say integrated config when there is some
pre-existing split config.

Signed-off-by: David Lamparter <equinox@diac24.net>
---
 debian/frr.postinst | 18 +++++++++++++++
 debian/frr.postrm   |  2 ++
 debian/frr.preinst  | 55 ++++++++++++++++++++++++++++++++++++++++++++-
 3 files changed, 74 insertions(+), 1 deletion(-)

diff --git a/debian/frr.postinst b/debian/frr.postinst
index 9be6f38018..a6dff333aa 100644
--- a/debian/frr.postinst
+++ b/debian/frr.postinst
@@ -64,10 +64,28 @@ the FRR service but its contents should be migrated to /etc/frr/daemons.
 EOF
 }
 
+rmsum() {
+	fname="$1"
+	test -f "$1" || return 0
+	fhash="`sha1sum \"$fname\"`"
+	fhash="${fhash%% *}"
+	if test "$fhash" = "$2"; then
+		rm "$fname"
+	fi
+}
+
 case "$1" in
 configure)
 	check_old_config /etc/frr/daemons.conf
 	check_old_config /etc/default/frr
+	if test -f /etc/frr/.pkg.frr.nointegrated; then
+		# remove integrated config setup
+		# (if checksums match, the files match freshly installed
+		# defaults, but the user has split config in place)
+		rmsum /etc/frr/vtysh.conf 5e7e3a488c51751e1ff98f27c9ad6085e1ad9cbb
+		rmsum /etc/frr/frr.conf   dac6f2af4fca9919ba40eb338885a5d1773195c8
+		rm /etc/frr/.pkg.frr.nointegrated
+	fi
 	;;
 esac
 
diff --git a/debian/frr.postrm b/debian/frr.postrm
index bbce0daf18..018f59e1c5 100644
--- a/debian/frr.postrm
+++ b/debian/frr.postrm
@@ -1,6 +1,8 @@
 #!/bin/sh
 set -e
 
+rm -f /etc/frr/.pkg.frr.nointegrated
+
 if [ "$1" = "purge" ]; then
 	rm -rf /run/frr || true
 
diff --git a/debian/frr.preinst b/debian/frr.preinst
index 56ebc707ca..fe087c6a7c 100644
--- a/debian/frr.preinst
+++ b/debian/frr.preinst
@@ -12,7 +12,7 @@ install|upgrade)
 
 		if [ "$watchfrr_enable" = no -o \
 			"$watchfrr_enable" = "0" ]; then
-			echo >&2 <<EOF
+			cat >&2 <<EOF
 ERROR: Pre-existing frr configuration file disables watchfrr.
 
 This configuration is deprecated upstream and not supported by the Debian
@@ -23,6 +23,59 @@ EOF
 			exit 1
 		fi
 	)
+	vtysh=''
+	if test -f /etc/frr/vtysh.conf; then
+		if grep -q '^[[:space:]]*service[[:space:]]\+integrated-vtysh-config' /etc/frr/vtysh.conf; then
+			# existing vtysh.conf with integrated statement
+			# - do nothing (=> integrated config)
+			vtysh='i'
+		elif grep -q '^[[:space:]]*no[[:space:]]\+service[[:space:]]\+integrated-vtysh-config' /etc/frr/vtysh.conf; then
+			# explicit non-integrated
+			# => need to fix vtysh.conf & frr.conf in postinst
+			vtysh='ni'
+			if test -f /etc/frr/frr.conf; then
+				cat >&2 <<EOF
+ERROR: Pre-existing /etc/frr/vtysh.conf specifies
+"no service integrated-vtysh-config", but /etc/frr/frr.conf exists.  This
+will cause the frr package to malfunction.  Please remove /etc/frr/frr.conf
+or remove the "no service integrated-vtysh-config" statement from
+/etc/frr/vtysh.conf.
+EOF
+				exit 1
+			fi
+		else
+			# vtysh.conf exists but has no statement
+			:
+		fi
+	fi
+	if test -f /etc/frr/frr.conf; then
+		# vtysh.conf has no explicit statement but frr.conf exists
+		# => integrated config used
+		vtysh='i'
+	elif test -f /etc/frr/zebra.conf \
+		-o -f /etc/frr/bgpd.conf \
+		-o -f /etc/frr/ospfd.conf \
+		-o -f /etc/frr/ospf6d.conf \
+		-o -f /etc/frr/ripd.conf \
+		-o -f /etc/frr/ripngd.conf \
+		-o -f /etc/frr/isisd.conf \
+		-o -f /etc/frr/pimd.conf \
+		-o -f /etc/frr/ldpd.conf \
+		-o -f /etc/frr/nhrpd.conf \
+		-o -f /etc/frr/eigrpd.conf \
+		-o -f /etc/frr/babeld.conf \
+		-o -f /etc/frr/pbrd.conf \
+		-o -f /etc/frr/bfdd.conf; then
+		# no explicit statement, but some split config file exists
+		# => need to fix vtysh.conf & frr.conf in postinst
+		test -n "$vtysh" || vtysh='ni'
+	else
+		# no config at all - use integrated
+		:
+	fi
+	if test "$vtysh" = "ni"; then
+		touch /etc/frr/.pkg.frr.nointegrated
+	fi
 	;;
 abort-upgrade)
 	# shouldn't fail an upgrade abort