filesystem-cleanup: Automatically remove old libraries

This script runs through /usr/lib and /lib and tries to find
all libraries which are no longer being used and more and
deletes them.

This will help us to free space on root partitions that
are limited to 2GB.

However, the script does not cover 100% of the cases, so that
some files still need to be deleted manually (e.g. boost with
their weird versioning schema).

This script should be executed after a Core Update has been
installed.

Fixes: #12270
Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>
Reviewed-by: Peter Müller <peter.mueller@ipfire.org>
Signed-off-by: Arne Fitzenreiter <arne_f@ipfire.org>

config/rootfiles/common/aarch64/stage2

@@ -92,6 +92,7 @@ usr/local/bin/backupiso
 usr/local/bin/connscheduler
 usr/local/bin/consort.sh
 usr/local/bin/convert-ovpn
+usr/local/bin/filesystem-cleanup
 usr/local/bin/hddshutdown
 usr/local/bin/ipsec-interfaces
 usr/local/bin/makegraphs

config/rootfiles/common/stage2

@@ -91,6 +91,7 @@ usr/local/bin/backupiso
 usr/local/bin/connscheduler
 usr/local/bin/consort.sh
 usr/local/bin/convert-ovpn
+usr/local/bin/filesystem-cleanup
 usr/local/bin/hddshutdown
 usr/local/bin/ipsec-interfaces
 usr/local/bin/makegraphs

config/rootfiles/common/x86_64/stage2

@@ -93,6 +93,7 @@ usr/local/bin/backupiso
 usr/local/bin/connscheduler
 usr/local/bin/consort.sh
 usr/local/bin/convert-ovpn
+usr/local/bin/filesystem-cleanup
 usr/local/bin/hddshutdown
 usr/local/bin/ipsec-interfaces
 usr/local/bin/makegraphs

src/scripts/filesystem-cleanup

@@ -0,0 +1,76 @@
+#!/bin/bash
+############################################################################
+#                                                                          #
+# This file is part of the IPFire Firewall.                                #
+#                                                                          #
+# IPFire is free software; you can redistribute it and/or modify           #
+# it under the terms of the GNU General Public License as published by     #
+# the Free Software Foundation; either version 2 of the License, or        #
+# (at your option) any later version.                                      #
+#                                                                          #
+# IPFire is distributed in the hope that it will be useful,                #
+# but WITHOUT ANY WARRANTY; without even the implied warranty of           #
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the            #
+# GNU General Public License for more details.                             #
+#                                                                          #
+# You should have received a copy of the GNU General Public License        #
+# along with IPFire; if not, write to the Free Software                    #
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA #
+#                                                                          #
+# Copyright (C) 2020 IPFire Team <info@ipfire.org>.                        #
+#                                                                          #
+############################################################################
+
+PATHS=(
+	/usr/lib
+	/lib
+)
+
+main() {
+	# Update the runtime linker cache (this may fix any broken symlinks)
+	ldconfig
+
+	local path
+	for path in ${PATHS[@]}; do
+		echo "Searching in ${path}..."
+
+		# Find all files called libsomething.so.N
+		local lib
+		for lib in $(find "${path}" -maxdepth 1 -type l -name "lib*.so.*" | sort); do
+			# Read the name of the linked library
+			local link="$(readlink -m "${lib}")"
+
+			# We have two versioning schemas that we need to distinguish...
+			local files=()
+			case "${link}" in
+				# Libraries called libsomething-N.so
+				*/lib*-*.so)
+					files+=( ${link%-*}-* )
+					;;
+
+				# Libraries called libsomething.so.N.*
+				*)
+					files+=( ${lib}* )
+					;;
+			esac
+
+			# Remove all files that have the same base name than
+			# the library we are looking at, apart from the symlink
+			# and the linked file itself.
+			local file
+			for file in ${files[@]}; do
+				case "${file}" in
+					# Ignore these files
+					${lib}|${link})
+						;;
+
+					*)
+						unlink "${file}"
+						;;
+				esac
+			done
+		done
+	done
+}
+
+main "$@" || exit $?