From 5dbd0b220f71caa79ce7cea06e1f0ccd6d927145 Mon Sep 17 00:00:00 2001
From: Tilo Spannagel <development@tilosp.de>
Date: Thu, 15 Mar 2018 12:29:55 +0100
Subject: [PATCH 1/4] Make docker-cron.sh posix compliant

---
 docker-cron.sh | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/docker-cron.sh b/docker-cron.sh
index bb65a1fb..4dfa4118 100755
--- a/docker-cron.sh
+++ b/docker-cron.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
-set -e
+#!/bin/sh
+set -eu
 
 exec busybox crond -f -l 0 -L /dev/stdout

From db233e28be7f1bf050385d6f3ba795ac48e49da3 Mon Sep 17 00:00:00 2001
From: Tilo Spannagel <development@tilosp.de>
Date: Thu, 15 Mar 2018 16:55:12 +0100
Subject: [PATCH 2/4] Make docker-entrypoint.sh posix compliant

---
 docker-entrypoint.sh | 44 +++++++++++++++++++++++---------------------
 1 file changed, 23 insertions(+), 21 deletions(-)

diff --git a/docker-entrypoint.sh b/docker-entrypoint.sh
index 0568aac1..8f3ac087 100755
--- a/docker-entrypoint.sh
+++ b/docker-entrypoint.sh
@@ -1,29 +1,31 @@
-#!/bin/bash
-set -e
+#!/bin/sh
+set -eu
 
 # version_greater A B returns whether A > B
-function version_greater() {
-	[[ "$(printf '%s\n' "$@" | sort -V | head -n 1)" != "$1" ]];
+version_greater() {
+	[ "$(printf '%s\n' "$@" | sort -t '.' -n -k1,1 -k2,2 -k3,3 -k4,4 | head -n 1)" != "$1" ]
 }
 
 # return true if specified directory is empty
-function directory_empty() {
-    [ -n "$(find "$1"/ -prune -empty)" ]
+directory_empty() {
+    [ -z "$(ls -A "$1/")" ]
 }
 
-function run_as() {
-  if [[ $EUID -eq 0 ]]; then
-    su - www-data -s /bin/bash -c "$1"
+run_as() {
+  if [ "$(id -u)" = 0 ]; then
+    su - www-data -s /bin/sh -c "$1"
   else
-    bash -c "$1"
+    sh -c "$1"
   fi
 }
 
-installed_version="0.0.0~unknown"
+installed_version="0.0.0.0"
 if [ -f /var/www/html/version.php ]; then
-    installed_version=$(php -r 'require "/var/www/html/version.php"; echo implode(".", $OC_Version);')
+    # shellcheck disable=SC2016
+    installed_version="$(php -r 'require "/var/www/html/version.php"; echo implode(".", $OC_Version);')"
 fi
-image_version=$(php -r 'require "/usr/src/nextcloud/version.php"; echo implode(".", $OC_Version);')
+# shellcheck disable=SC2016
+image_version="$(php -r 'require "/usr/src/nextcloud/version.php"; echo implode(".", $OC_Version);')"
 
 if version_greater "$installed_version" "$image_version"; then
     echo "Can't start Nextcloud because the version of the data ($installed_version) is higher than the docker image version ($image_version) and downgrading is not supported. Are you sure you have pulled the newest image version?"
@@ -31,10 +33,10 @@ if version_greater "$installed_version" "$image_version"; then
 fi
 
 if version_greater "$image_version" "$installed_version"; then
-    if [ "$installed_version" != "0.0.0~unknown" ]; then
-        run_as 'php /var/www/html/occ app:list' > /tmp/list_before
+    if [ "$installed_version" != "0.0.0.0" ]; then
+        run_as 'php /var/www/html/occ app:list' | sed -n "/Enabled:/,/Disabled:/p" > /tmp/list_before
     fi
-    if [[ $EUID -eq 0 ]]; then
+    if [ "$(id -u)" = 0 ]; then
       rsync_options="-rlDog --chown www-data:root"
     else
       rsync_options="-rlD"
@@ -42,17 +44,17 @@ if version_greater "$image_version" "$installed_version"; then
     rsync $rsync_options --delete --exclude /config/ --exclude /data/ --exclude /custom_apps/ --exclude /themes/ /usr/src/nextcloud/ /var/www/html/
 
     for dir in config data custom_apps themes; do
-        if [ ! -d /var/www/html/"$dir" ] || directory_empty /var/www/html/"$dir"; then
-            rsync $rsync_options --include /"$dir"/ --exclude '/*' /usr/src/nextcloud/ /var/www/html/
+        if [ ! -d "/var/www/html/$dir" ] || directory_empty "/var/www/html/$dir"; then
+            rsync $rsync_options --include "/$dir/" --exclude '/*' /usr/src/nextcloud/ /var/www/html/
         fi
     done
 
-    if [ "$installed_version" != "0.0.0~unknown" ]; then
+    if [ "$installed_version" != "0.0.0.0" ]; then
         run_as 'php /var/www/html/occ upgrade --no-app-disable'
 
-        run_as 'php /var/www/html/occ app:list' > /tmp/list_after
+        run_as 'php /var/www/html/occ app:list' | sed -n "/Enabled:/,/Disabled:/p" > /tmp/list_after
         echo "The following apps have beed disabled:"
-        diff <(sed -n "/Enabled:/,/Disabled:/p" /tmp/list_before) <(sed -n "/Enabled:/,/Disabled:/p" /tmp/list_after) | grep '<' | cut -d- -f2 | cut -d: -f1
+        diff /tmp/list_before /tmp/list_after | grep '<' | cut -d- -f2 | cut -d: -f1
         rm -f /tmp/list_before /tmp/list_after
     fi
 fi

From f4cb78945e2d2888d30544433c938040ea081d69 Mon Sep 17 00:00:00 2001
From: Tilo Spannagel <development@tilosp.de>
Date: Thu, 15 Mar 2018 16:59:08 +0100
Subject: [PATCH 3/4] Remove bash dependency from alpine variant

---
 Dockerfile-alpine.template | 2 --
 1 file changed, 2 deletions(-)

diff --git a/Dockerfile-alpine.template b/Dockerfile-alpine.template
index cd75dae5..03526a1c 100644
--- a/Dockerfile-alpine.template
+++ b/Dockerfile-alpine.template
@@ -4,8 +4,6 @@ FROM php:%%PHP_VERSION%%-%%VARIANT%%
 RUN set -ex; \
     \
     apk add --no-cache \
-        bash \
-        coreutils \
         rsync \
     ; \
     \

From 07e61395c63a8c14c837a07384476184cfa96aa2 Mon Sep 17 00:00:00 2001
From: Tilo Spannagel <development@tilosp.de>
Date: Thu, 15 Mar 2018 17:41:36 +0100
Subject: [PATCH 4/4] Run update.sh

---
 11.0/apache/cron.sh           |  4 ++--
 11.0/apache/entrypoint.sh     | 44 ++++++++++++++++++-----------------
 11.0/fpm-alpine/Dockerfile    |  2 --
 11.0/fpm-alpine/cron.sh       |  4 ++--
 11.0/fpm-alpine/entrypoint.sh | 44 ++++++++++++++++++-----------------
 11.0/fpm/cron.sh              |  4 ++--
 11.0/fpm/entrypoint.sh        | 44 ++++++++++++++++++-----------------
 12.0/apache/cron.sh           |  4 ++--
 12.0/apache/entrypoint.sh     | 44 ++++++++++++++++++-----------------
 12.0/fpm-alpine/Dockerfile    |  2 --
 12.0/fpm-alpine/cron.sh       |  4 ++--
 12.0/fpm-alpine/entrypoint.sh | 44 ++++++++++++++++++-----------------
 12.0/fpm/cron.sh              |  4 ++--
 12.0/fpm/entrypoint.sh        | 44 ++++++++++++++++++-----------------
 13.0/apache/cron.sh           |  4 ++--
 13.0/apache/entrypoint.sh     | 44 ++++++++++++++++++-----------------
 13.0/fpm-alpine/Dockerfile    |  2 --
 13.0/fpm-alpine/cron.sh       |  4 ++--
 13.0/fpm-alpine/entrypoint.sh | 44 ++++++++++++++++++-----------------
 13.0/fpm/cron.sh              |  4 ++--
 13.0/fpm/entrypoint.sh        | 44 ++++++++++++++++++-----------------
 21 files changed, 225 insertions(+), 213 deletions(-)

diff --git a/11.0/apache/cron.sh b/11.0/apache/cron.sh
index bb65a1fb..4dfa4118 100755
--- a/11.0/apache/cron.sh
+++ b/11.0/apache/cron.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
-set -e
+#!/bin/sh
+set -eu
 
 exec busybox crond -f -l 0 -L /dev/stdout
diff --git a/11.0/apache/entrypoint.sh b/11.0/apache/entrypoint.sh
index 0568aac1..8f3ac087 100755
--- a/11.0/apache/entrypoint.sh
+++ b/11.0/apache/entrypoint.sh
@@ -1,29 +1,31 @@
-#!/bin/bash
-set -e
+#!/bin/sh
+set -eu
 
 # version_greater A B returns whether A > B
-function version_greater() {
-	[[ "$(printf '%s\n' "$@" | sort -V | head -n 1)" != "$1" ]];
+version_greater() {
+	[ "$(printf '%s\n' "$@" | sort -t '.' -n -k1,1 -k2,2 -k3,3 -k4,4 | head -n 1)" != "$1" ]
 }
 
 # return true if specified directory is empty
-function directory_empty() {
-    [ -n "$(find "$1"/ -prune -empty)" ]
+directory_empty() {
+    [ -z "$(ls -A "$1/")" ]
 }
 
-function run_as() {
-  if [[ $EUID -eq 0 ]]; then
-    su - www-data -s /bin/bash -c "$1"
+run_as() {
+  if [ "$(id -u)" = 0 ]; then
+    su - www-data -s /bin/sh -c "$1"
   else
-    bash -c "$1"
+    sh -c "$1"
   fi
 }
 
-installed_version="0.0.0~unknown"
+installed_version="0.0.0.0"
 if [ -f /var/www/html/version.php ]; then
-    installed_version=$(php -r 'require "/var/www/html/version.php"; echo implode(".", $OC_Version);')
+    # shellcheck disable=SC2016
+    installed_version="$(php -r 'require "/var/www/html/version.php"; echo implode(".", $OC_Version);')"
 fi
-image_version=$(php -r 'require "/usr/src/nextcloud/version.php"; echo implode(".", $OC_Version);')
+# shellcheck disable=SC2016
+image_version="$(php -r 'require "/usr/src/nextcloud/version.php"; echo implode(".", $OC_Version);')"
 
 if version_greater "$installed_version" "$image_version"; then
     echo "Can't start Nextcloud because the version of the data ($installed_version) is higher than the docker image version ($image_version) and downgrading is not supported. Are you sure you have pulled the newest image version?"
@@ -31,10 +33,10 @@ if version_greater "$installed_version" "$image_version"; then
 fi
 
 if version_greater "$image_version" "$installed_version"; then
-    if [ "$installed_version" != "0.0.0~unknown" ]; then
-        run_as 'php /var/www/html/occ app:list' > /tmp/list_before
+    if [ "$installed_version" != "0.0.0.0" ]; then
+        run_as 'php /var/www/html/occ app:list' | sed -n "/Enabled:/,/Disabled:/p" > /tmp/list_before
     fi
-    if [[ $EUID -eq 0 ]]; then
+    if [ "$(id -u)" = 0 ]; then
       rsync_options="-rlDog --chown www-data:root"
     else
       rsync_options="-rlD"
@@ -42,17 +44,17 @@ if version_greater "$image_version" "$installed_version"; then
     rsync $rsync_options --delete --exclude /config/ --exclude /data/ --exclude /custom_apps/ --exclude /themes/ /usr/src/nextcloud/ /var/www/html/
 
     for dir in config data custom_apps themes; do
-        if [ ! -d /var/www/html/"$dir" ] || directory_empty /var/www/html/"$dir"; then
-            rsync $rsync_options --include /"$dir"/ --exclude '/*' /usr/src/nextcloud/ /var/www/html/
+        if [ ! -d "/var/www/html/$dir" ] || directory_empty "/var/www/html/$dir"; then
+            rsync $rsync_options --include "/$dir/" --exclude '/*' /usr/src/nextcloud/ /var/www/html/
         fi
     done
 
-    if [ "$installed_version" != "0.0.0~unknown" ]; then
+    if [ "$installed_version" != "0.0.0.0" ]; then
         run_as 'php /var/www/html/occ upgrade --no-app-disable'
 
-        run_as 'php /var/www/html/occ app:list' > /tmp/list_after
+        run_as 'php /var/www/html/occ app:list' | sed -n "/Enabled:/,/Disabled:/p" > /tmp/list_after
         echo "The following apps have beed disabled:"
-        diff <(sed -n "/Enabled:/,/Disabled:/p" /tmp/list_before) <(sed -n "/Enabled:/,/Disabled:/p" /tmp/list_after) | grep '<' | cut -d- -f2 | cut -d: -f1
+        diff /tmp/list_before /tmp/list_after | grep '<' | cut -d- -f2 | cut -d: -f1
         rm -f /tmp/list_before /tmp/list_after
     fi
 fi
diff --git a/11.0/fpm-alpine/Dockerfile b/11.0/fpm-alpine/Dockerfile
index eabb5fe0..198eba7c 100644
--- a/11.0/fpm-alpine/Dockerfile
+++ b/11.0/fpm-alpine/Dockerfile
@@ -4,8 +4,6 @@ FROM php:7.1-fpm-alpine
 RUN set -ex; \
     \
     apk add --no-cache \
-        bash \
-        coreutils \
         rsync \
     ; \
     \
diff --git a/11.0/fpm-alpine/cron.sh b/11.0/fpm-alpine/cron.sh
index bb65a1fb..4dfa4118 100755
--- a/11.0/fpm-alpine/cron.sh
+++ b/11.0/fpm-alpine/cron.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
-set -e
+#!/bin/sh
+set -eu
 
 exec busybox crond -f -l 0 -L /dev/stdout
diff --git a/11.0/fpm-alpine/entrypoint.sh b/11.0/fpm-alpine/entrypoint.sh
index 0568aac1..8f3ac087 100755
--- a/11.0/fpm-alpine/entrypoint.sh
+++ b/11.0/fpm-alpine/entrypoint.sh
@@ -1,29 +1,31 @@
-#!/bin/bash
-set -e
+#!/bin/sh
+set -eu
 
 # version_greater A B returns whether A > B
-function version_greater() {
-	[[ "$(printf '%s\n' "$@" | sort -V | head -n 1)" != "$1" ]];
+version_greater() {
+	[ "$(printf '%s\n' "$@" | sort -t '.' -n -k1,1 -k2,2 -k3,3 -k4,4 | head -n 1)" != "$1" ]
 }
 
 # return true if specified directory is empty
-function directory_empty() {
-    [ -n "$(find "$1"/ -prune -empty)" ]
+directory_empty() {
+    [ -z "$(ls -A "$1/")" ]
 }
 
-function run_as() {
-  if [[ $EUID -eq 0 ]]; then
-    su - www-data -s /bin/bash -c "$1"
+run_as() {
+  if [ "$(id -u)" = 0 ]; then
+    su - www-data -s /bin/sh -c "$1"
   else
-    bash -c "$1"
+    sh -c "$1"
   fi
 }
 
-installed_version="0.0.0~unknown"
+installed_version="0.0.0.0"
 if [ -f /var/www/html/version.php ]; then
-    installed_version=$(php -r 'require "/var/www/html/version.php"; echo implode(".", $OC_Version);')
+    # shellcheck disable=SC2016
+    installed_version="$(php -r 'require "/var/www/html/version.php"; echo implode(".", $OC_Version);')"
 fi
-image_version=$(php -r 'require "/usr/src/nextcloud/version.php"; echo implode(".", $OC_Version);')
+# shellcheck disable=SC2016
+image_version="$(php -r 'require "/usr/src/nextcloud/version.php"; echo implode(".", $OC_Version);')"
 
 if version_greater "$installed_version" "$image_version"; then
     echo "Can't start Nextcloud because the version of the data ($installed_version) is higher than the docker image version ($image_version) and downgrading is not supported. Are you sure you have pulled the newest image version?"
@@ -31,10 +33,10 @@ if version_greater "$installed_version" "$image_version"; then
 fi
 
 if version_greater "$image_version" "$installed_version"; then
-    if [ "$installed_version" != "0.0.0~unknown" ]; then
-        run_as 'php /var/www/html/occ app:list' > /tmp/list_before
+    if [ "$installed_version" != "0.0.0.0" ]; then
+        run_as 'php /var/www/html/occ app:list' | sed -n "/Enabled:/,/Disabled:/p" > /tmp/list_before
     fi
-    if [[ $EUID -eq 0 ]]; then
+    if [ "$(id -u)" = 0 ]; then
       rsync_options="-rlDog --chown www-data:root"
     else
       rsync_options="-rlD"
@@ -42,17 +44,17 @@ if version_greater "$image_version" "$installed_version"; then
     rsync $rsync_options --delete --exclude /config/ --exclude /data/ --exclude /custom_apps/ --exclude /themes/ /usr/src/nextcloud/ /var/www/html/
 
     for dir in config data custom_apps themes; do
-        if [ ! -d /var/www/html/"$dir" ] || directory_empty /var/www/html/"$dir"; then
-            rsync $rsync_options --include /"$dir"/ --exclude '/*' /usr/src/nextcloud/ /var/www/html/
+        if [ ! -d "/var/www/html/$dir" ] || directory_empty "/var/www/html/$dir"; then
+            rsync $rsync_options --include "/$dir/" --exclude '/*' /usr/src/nextcloud/ /var/www/html/
         fi
     done
 
-    if [ "$installed_version" != "0.0.0~unknown" ]; then
+    if [ "$installed_version" != "0.0.0.0" ]; then
         run_as 'php /var/www/html/occ upgrade --no-app-disable'
 
-        run_as 'php /var/www/html/occ app:list' > /tmp/list_after
+        run_as 'php /var/www/html/occ app:list' | sed -n "/Enabled:/,/Disabled:/p" > /tmp/list_after
         echo "The following apps have beed disabled:"
-        diff <(sed -n "/Enabled:/,/Disabled:/p" /tmp/list_before) <(sed -n "/Enabled:/,/Disabled:/p" /tmp/list_after) | grep '<' | cut -d- -f2 | cut -d: -f1
+        diff /tmp/list_before /tmp/list_after | grep '<' | cut -d- -f2 | cut -d: -f1
         rm -f /tmp/list_before /tmp/list_after
     fi
 fi
diff --git a/11.0/fpm/cron.sh b/11.0/fpm/cron.sh
index bb65a1fb..4dfa4118 100755
--- a/11.0/fpm/cron.sh
+++ b/11.0/fpm/cron.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
-set -e
+#!/bin/sh
+set -eu
 
 exec busybox crond -f -l 0 -L /dev/stdout
diff --git a/11.0/fpm/entrypoint.sh b/11.0/fpm/entrypoint.sh
index 0568aac1..8f3ac087 100755
--- a/11.0/fpm/entrypoint.sh
+++ b/11.0/fpm/entrypoint.sh
@@ -1,29 +1,31 @@
-#!/bin/bash
-set -e
+#!/bin/sh
+set -eu
 
 # version_greater A B returns whether A > B
-function version_greater() {
-	[[ "$(printf '%s\n' "$@" | sort -V | head -n 1)" != "$1" ]];
+version_greater() {
+	[ "$(printf '%s\n' "$@" | sort -t '.' -n -k1,1 -k2,2 -k3,3 -k4,4 | head -n 1)" != "$1" ]
 }
 
 # return true if specified directory is empty
-function directory_empty() {
-    [ -n "$(find "$1"/ -prune -empty)" ]
+directory_empty() {
+    [ -z "$(ls -A "$1/")" ]
 }
 
-function run_as() {
-  if [[ $EUID -eq 0 ]]; then
-    su - www-data -s /bin/bash -c "$1"
+run_as() {
+  if [ "$(id -u)" = 0 ]; then
+    su - www-data -s /bin/sh -c "$1"
   else
-    bash -c "$1"
+    sh -c "$1"
   fi
 }
 
-installed_version="0.0.0~unknown"
+installed_version="0.0.0.0"
 if [ -f /var/www/html/version.php ]; then
-    installed_version=$(php -r 'require "/var/www/html/version.php"; echo implode(".", $OC_Version);')
+    # shellcheck disable=SC2016
+    installed_version="$(php -r 'require "/var/www/html/version.php"; echo implode(".", $OC_Version);')"
 fi
-image_version=$(php -r 'require "/usr/src/nextcloud/version.php"; echo implode(".", $OC_Version);')
+# shellcheck disable=SC2016
+image_version="$(php -r 'require "/usr/src/nextcloud/version.php"; echo implode(".", $OC_Version);')"
 
 if version_greater "$installed_version" "$image_version"; then
     echo "Can't start Nextcloud because the version of the data ($installed_version) is higher than the docker image version ($image_version) and downgrading is not supported. Are you sure you have pulled the newest image version?"
@@ -31,10 +33,10 @@ if version_greater "$installed_version" "$image_version"; then
 fi
 
 if version_greater "$image_version" "$installed_version"; then
-    if [ "$installed_version" != "0.0.0~unknown" ]; then
-        run_as 'php /var/www/html/occ app:list' > /tmp/list_before
+    if [ "$installed_version" != "0.0.0.0" ]; then
+        run_as 'php /var/www/html/occ app:list' | sed -n "/Enabled:/,/Disabled:/p" > /tmp/list_before
     fi
-    if [[ $EUID -eq 0 ]]; then
+    if [ "$(id -u)" = 0 ]; then
       rsync_options="-rlDog --chown www-data:root"
     else
       rsync_options="-rlD"
@@ -42,17 +44,17 @@ if version_greater "$image_version" "$installed_version"; then
     rsync $rsync_options --delete --exclude /config/ --exclude /data/ --exclude /custom_apps/ --exclude /themes/ /usr/src/nextcloud/ /var/www/html/
 
     for dir in config data custom_apps themes; do
-        if [ ! -d /var/www/html/"$dir" ] || directory_empty /var/www/html/"$dir"; then
-            rsync $rsync_options --include /"$dir"/ --exclude '/*' /usr/src/nextcloud/ /var/www/html/
+        if [ ! -d "/var/www/html/$dir" ] || directory_empty "/var/www/html/$dir"; then
+            rsync $rsync_options --include "/$dir/" --exclude '/*' /usr/src/nextcloud/ /var/www/html/
         fi
     done
 
-    if [ "$installed_version" != "0.0.0~unknown" ]; then
+    if [ "$installed_version" != "0.0.0.0" ]; then
         run_as 'php /var/www/html/occ upgrade --no-app-disable'
 
-        run_as 'php /var/www/html/occ app:list' > /tmp/list_after
+        run_as 'php /var/www/html/occ app:list' | sed -n "/Enabled:/,/Disabled:/p" > /tmp/list_after
         echo "The following apps have beed disabled:"
-        diff <(sed -n "/Enabled:/,/Disabled:/p" /tmp/list_before) <(sed -n "/Enabled:/,/Disabled:/p" /tmp/list_after) | grep '<' | cut -d- -f2 | cut -d: -f1
+        diff /tmp/list_before /tmp/list_after | grep '<' | cut -d- -f2 | cut -d: -f1
         rm -f /tmp/list_before /tmp/list_after
     fi
 fi
diff --git a/12.0/apache/cron.sh b/12.0/apache/cron.sh
index bb65a1fb..4dfa4118 100755
--- a/12.0/apache/cron.sh
+++ b/12.0/apache/cron.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
-set -e
+#!/bin/sh
+set -eu
 
 exec busybox crond -f -l 0 -L /dev/stdout
diff --git a/12.0/apache/entrypoint.sh b/12.0/apache/entrypoint.sh
index 0568aac1..8f3ac087 100755
--- a/12.0/apache/entrypoint.sh
+++ b/12.0/apache/entrypoint.sh
@@ -1,29 +1,31 @@
-#!/bin/bash
-set -e
+#!/bin/sh
+set -eu
 
 # version_greater A B returns whether A > B
-function version_greater() {
-	[[ "$(printf '%s\n' "$@" | sort -V | head -n 1)" != "$1" ]];
+version_greater() {
+	[ "$(printf '%s\n' "$@" | sort -t '.' -n -k1,1 -k2,2 -k3,3 -k4,4 | head -n 1)" != "$1" ]
 }
 
 # return true if specified directory is empty
-function directory_empty() {
-    [ -n "$(find "$1"/ -prune -empty)" ]
+directory_empty() {
+    [ -z "$(ls -A "$1/")" ]
 }
 
-function run_as() {
-  if [[ $EUID -eq 0 ]]; then
-    su - www-data -s /bin/bash -c "$1"
+run_as() {
+  if [ "$(id -u)" = 0 ]; then
+    su - www-data -s /bin/sh -c "$1"
   else
-    bash -c "$1"
+    sh -c "$1"
   fi
 }
 
-installed_version="0.0.0~unknown"
+installed_version="0.0.0.0"
 if [ -f /var/www/html/version.php ]; then
-    installed_version=$(php -r 'require "/var/www/html/version.php"; echo implode(".", $OC_Version);')
+    # shellcheck disable=SC2016
+    installed_version="$(php -r 'require "/var/www/html/version.php"; echo implode(".", $OC_Version);')"
 fi
-image_version=$(php -r 'require "/usr/src/nextcloud/version.php"; echo implode(".", $OC_Version);')
+# shellcheck disable=SC2016
+image_version="$(php -r 'require "/usr/src/nextcloud/version.php"; echo implode(".", $OC_Version);')"
 
 if version_greater "$installed_version" "$image_version"; then
     echo "Can't start Nextcloud because the version of the data ($installed_version) is higher than the docker image version ($image_version) and downgrading is not supported. Are you sure you have pulled the newest image version?"
@@ -31,10 +33,10 @@ if version_greater "$installed_version" "$image_version"; then
 fi
 
 if version_greater "$image_version" "$installed_version"; then
-    if [ "$installed_version" != "0.0.0~unknown" ]; then
-        run_as 'php /var/www/html/occ app:list' > /tmp/list_before
+    if [ "$installed_version" != "0.0.0.0" ]; then
+        run_as 'php /var/www/html/occ app:list' | sed -n "/Enabled:/,/Disabled:/p" > /tmp/list_before
     fi
-    if [[ $EUID -eq 0 ]]; then
+    if [ "$(id -u)" = 0 ]; then
       rsync_options="-rlDog --chown www-data:root"
     else
       rsync_options="-rlD"
@@ -42,17 +44,17 @@ if version_greater "$image_version" "$installed_version"; then
     rsync $rsync_options --delete --exclude /config/ --exclude /data/ --exclude /custom_apps/ --exclude /themes/ /usr/src/nextcloud/ /var/www/html/
 
     for dir in config data custom_apps themes; do
-        if [ ! -d /var/www/html/"$dir" ] || directory_empty /var/www/html/"$dir"; then
-            rsync $rsync_options --include /"$dir"/ --exclude '/*' /usr/src/nextcloud/ /var/www/html/
+        if [ ! -d "/var/www/html/$dir" ] || directory_empty "/var/www/html/$dir"; then
+            rsync $rsync_options --include "/$dir/" --exclude '/*' /usr/src/nextcloud/ /var/www/html/
         fi
     done
 
-    if [ "$installed_version" != "0.0.0~unknown" ]; then
+    if [ "$installed_version" != "0.0.0.0" ]; then
         run_as 'php /var/www/html/occ upgrade --no-app-disable'
 
-        run_as 'php /var/www/html/occ app:list' > /tmp/list_after
+        run_as 'php /var/www/html/occ app:list' | sed -n "/Enabled:/,/Disabled:/p" > /tmp/list_after
         echo "The following apps have beed disabled:"
-        diff <(sed -n "/Enabled:/,/Disabled:/p" /tmp/list_before) <(sed -n "/Enabled:/,/Disabled:/p" /tmp/list_after) | grep '<' | cut -d- -f2 | cut -d: -f1
+        diff /tmp/list_before /tmp/list_after | grep '<' | cut -d- -f2 | cut -d: -f1
         rm -f /tmp/list_before /tmp/list_after
     fi
 fi
diff --git a/12.0/fpm-alpine/Dockerfile b/12.0/fpm-alpine/Dockerfile
index cf084b9e..9a76cac2 100644
--- a/12.0/fpm-alpine/Dockerfile
+++ b/12.0/fpm-alpine/Dockerfile
@@ -4,8 +4,6 @@ FROM php:7.1-fpm-alpine
 RUN set -ex; \
     \
     apk add --no-cache \
-        bash \
-        coreutils \
         rsync \
     ; \
     \
diff --git a/12.0/fpm-alpine/cron.sh b/12.0/fpm-alpine/cron.sh
index bb65a1fb..4dfa4118 100755
--- a/12.0/fpm-alpine/cron.sh
+++ b/12.0/fpm-alpine/cron.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
-set -e
+#!/bin/sh
+set -eu
 
 exec busybox crond -f -l 0 -L /dev/stdout
diff --git a/12.0/fpm-alpine/entrypoint.sh b/12.0/fpm-alpine/entrypoint.sh
index 0568aac1..8f3ac087 100755
--- a/12.0/fpm-alpine/entrypoint.sh
+++ b/12.0/fpm-alpine/entrypoint.sh
@@ -1,29 +1,31 @@
-#!/bin/bash
-set -e
+#!/bin/sh
+set -eu
 
 # version_greater A B returns whether A > B
-function version_greater() {
-	[[ "$(printf '%s\n' "$@" | sort -V | head -n 1)" != "$1" ]];
+version_greater() {
+	[ "$(printf '%s\n' "$@" | sort -t '.' -n -k1,1 -k2,2 -k3,3 -k4,4 | head -n 1)" != "$1" ]
 }
 
 # return true if specified directory is empty
-function directory_empty() {
-    [ -n "$(find "$1"/ -prune -empty)" ]
+directory_empty() {
+    [ -z "$(ls -A "$1/")" ]
 }
 
-function run_as() {
-  if [[ $EUID -eq 0 ]]; then
-    su - www-data -s /bin/bash -c "$1"
+run_as() {
+  if [ "$(id -u)" = 0 ]; then
+    su - www-data -s /bin/sh -c "$1"
   else
-    bash -c "$1"
+    sh -c "$1"
   fi
 }
 
-installed_version="0.0.0~unknown"
+installed_version="0.0.0.0"
 if [ -f /var/www/html/version.php ]; then
-    installed_version=$(php -r 'require "/var/www/html/version.php"; echo implode(".", $OC_Version);')
+    # shellcheck disable=SC2016
+    installed_version="$(php -r 'require "/var/www/html/version.php"; echo implode(".", $OC_Version);')"
 fi
-image_version=$(php -r 'require "/usr/src/nextcloud/version.php"; echo implode(".", $OC_Version);')
+# shellcheck disable=SC2016
+image_version="$(php -r 'require "/usr/src/nextcloud/version.php"; echo implode(".", $OC_Version);')"
 
 if version_greater "$installed_version" "$image_version"; then
     echo "Can't start Nextcloud because the version of the data ($installed_version) is higher than the docker image version ($image_version) and downgrading is not supported. Are you sure you have pulled the newest image version?"
@@ -31,10 +33,10 @@ if version_greater "$installed_version" "$image_version"; then
 fi
 
 if version_greater "$image_version" "$installed_version"; then
-    if [ "$installed_version" != "0.0.0~unknown" ]; then
-        run_as 'php /var/www/html/occ app:list' > /tmp/list_before
+    if [ "$installed_version" != "0.0.0.0" ]; then
+        run_as 'php /var/www/html/occ app:list' | sed -n "/Enabled:/,/Disabled:/p" > /tmp/list_before
     fi
-    if [[ $EUID -eq 0 ]]; then
+    if [ "$(id -u)" = 0 ]; then
       rsync_options="-rlDog --chown www-data:root"
     else
       rsync_options="-rlD"
@@ -42,17 +44,17 @@ if version_greater "$image_version" "$installed_version"; then
     rsync $rsync_options --delete --exclude /config/ --exclude /data/ --exclude /custom_apps/ --exclude /themes/ /usr/src/nextcloud/ /var/www/html/
 
     for dir in config data custom_apps themes; do
-        if [ ! -d /var/www/html/"$dir" ] || directory_empty /var/www/html/"$dir"; then
-            rsync $rsync_options --include /"$dir"/ --exclude '/*' /usr/src/nextcloud/ /var/www/html/
+        if [ ! -d "/var/www/html/$dir" ] || directory_empty "/var/www/html/$dir"; then
+            rsync $rsync_options --include "/$dir/" --exclude '/*' /usr/src/nextcloud/ /var/www/html/
         fi
     done
 
-    if [ "$installed_version" != "0.0.0~unknown" ]; then
+    if [ "$installed_version" != "0.0.0.0" ]; then
         run_as 'php /var/www/html/occ upgrade --no-app-disable'
 
-        run_as 'php /var/www/html/occ app:list' > /tmp/list_after
+        run_as 'php /var/www/html/occ app:list' | sed -n "/Enabled:/,/Disabled:/p" > /tmp/list_after
         echo "The following apps have beed disabled:"
-        diff <(sed -n "/Enabled:/,/Disabled:/p" /tmp/list_before) <(sed -n "/Enabled:/,/Disabled:/p" /tmp/list_after) | grep '<' | cut -d- -f2 | cut -d: -f1
+        diff /tmp/list_before /tmp/list_after | grep '<' | cut -d- -f2 | cut -d: -f1
         rm -f /tmp/list_before /tmp/list_after
     fi
 fi
diff --git a/12.0/fpm/cron.sh b/12.0/fpm/cron.sh
index bb65a1fb..4dfa4118 100755
--- a/12.0/fpm/cron.sh
+++ b/12.0/fpm/cron.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
-set -e
+#!/bin/sh
+set -eu
 
 exec busybox crond -f -l 0 -L /dev/stdout
diff --git a/12.0/fpm/entrypoint.sh b/12.0/fpm/entrypoint.sh
index 0568aac1..8f3ac087 100755
--- a/12.0/fpm/entrypoint.sh
+++ b/12.0/fpm/entrypoint.sh
@@ -1,29 +1,31 @@
-#!/bin/bash
-set -e
+#!/bin/sh
+set -eu
 
 # version_greater A B returns whether A > B
-function version_greater() {
-	[[ "$(printf '%s\n' "$@" | sort -V | head -n 1)" != "$1" ]];
+version_greater() {
+	[ "$(printf '%s\n' "$@" | sort -t '.' -n -k1,1 -k2,2 -k3,3 -k4,4 | head -n 1)" != "$1" ]
 }
 
 # return true if specified directory is empty
-function directory_empty() {
-    [ -n "$(find "$1"/ -prune -empty)" ]
+directory_empty() {
+    [ -z "$(ls -A "$1/")" ]
 }
 
-function run_as() {
-  if [[ $EUID -eq 0 ]]; then
-    su - www-data -s /bin/bash -c "$1"
+run_as() {
+  if [ "$(id -u)" = 0 ]; then
+    su - www-data -s /bin/sh -c "$1"
   else
-    bash -c "$1"
+    sh -c "$1"
   fi
 }
 
-installed_version="0.0.0~unknown"
+installed_version="0.0.0.0"
 if [ -f /var/www/html/version.php ]; then
-    installed_version=$(php -r 'require "/var/www/html/version.php"; echo implode(".", $OC_Version);')
+    # shellcheck disable=SC2016
+    installed_version="$(php -r 'require "/var/www/html/version.php"; echo implode(".", $OC_Version);')"
 fi
-image_version=$(php -r 'require "/usr/src/nextcloud/version.php"; echo implode(".", $OC_Version);')
+# shellcheck disable=SC2016
+image_version="$(php -r 'require "/usr/src/nextcloud/version.php"; echo implode(".", $OC_Version);')"
 
 if version_greater "$installed_version" "$image_version"; then
     echo "Can't start Nextcloud because the version of the data ($installed_version) is higher than the docker image version ($image_version) and downgrading is not supported. Are you sure you have pulled the newest image version?"
@@ -31,10 +33,10 @@ if version_greater "$installed_version" "$image_version"; then
 fi
 
 if version_greater "$image_version" "$installed_version"; then
-    if [ "$installed_version" != "0.0.0~unknown" ]; then
-        run_as 'php /var/www/html/occ app:list' > /tmp/list_before
+    if [ "$installed_version" != "0.0.0.0" ]; then
+        run_as 'php /var/www/html/occ app:list' | sed -n "/Enabled:/,/Disabled:/p" > /tmp/list_before
     fi
-    if [[ $EUID -eq 0 ]]; then
+    if [ "$(id -u)" = 0 ]; then
       rsync_options="-rlDog --chown www-data:root"
     else
       rsync_options="-rlD"
@@ -42,17 +44,17 @@ if version_greater "$image_version" "$installed_version"; then
     rsync $rsync_options --delete --exclude /config/ --exclude /data/ --exclude /custom_apps/ --exclude /themes/ /usr/src/nextcloud/ /var/www/html/
 
     for dir in config data custom_apps themes; do
-        if [ ! -d /var/www/html/"$dir" ] || directory_empty /var/www/html/"$dir"; then
-            rsync $rsync_options --include /"$dir"/ --exclude '/*' /usr/src/nextcloud/ /var/www/html/
+        if [ ! -d "/var/www/html/$dir" ] || directory_empty "/var/www/html/$dir"; then
+            rsync $rsync_options --include "/$dir/" --exclude '/*' /usr/src/nextcloud/ /var/www/html/
         fi
     done
 
-    if [ "$installed_version" != "0.0.0~unknown" ]; then
+    if [ "$installed_version" != "0.0.0.0" ]; then
         run_as 'php /var/www/html/occ upgrade --no-app-disable'
 
-        run_as 'php /var/www/html/occ app:list' > /tmp/list_after
+        run_as 'php /var/www/html/occ app:list' | sed -n "/Enabled:/,/Disabled:/p" > /tmp/list_after
         echo "The following apps have beed disabled:"
-        diff <(sed -n "/Enabled:/,/Disabled:/p" /tmp/list_before) <(sed -n "/Enabled:/,/Disabled:/p" /tmp/list_after) | grep '<' | cut -d- -f2 | cut -d: -f1
+        diff /tmp/list_before /tmp/list_after | grep '<' | cut -d- -f2 | cut -d: -f1
         rm -f /tmp/list_before /tmp/list_after
     fi
 fi
diff --git a/13.0/apache/cron.sh b/13.0/apache/cron.sh
index bb65a1fb..4dfa4118 100755
--- a/13.0/apache/cron.sh
+++ b/13.0/apache/cron.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
-set -e
+#!/bin/sh
+set -eu
 
 exec busybox crond -f -l 0 -L /dev/stdout
diff --git a/13.0/apache/entrypoint.sh b/13.0/apache/entrypoint.sh
index 0568aac1..8f3ac087 100755
--- a/13.0/apache/entrypoint.sh
+++ b/13.0/apache/entrypoint.sh
@@ -1,29 +1,31 @@
-#!/bin/bash
-set -e
+#!/bin/sh
+set -eu
 
 # version_greater A B returns whether A > B
-function version_greater() {
-	[[ "$(printf '%s\n' "$@" | sort -V | head -n 1)" != "$1" ]];
+version_greater() {
+	[ "$(printf '%s\n' "$@" | sort -t '.' -n -k1,1 -k2,2 -k3,3 -k4,4 | head -n 1)" != "$1" ]
 }
 
 # return true if specified directory is empty
-function directory_empty() {
-    [ -n "$(find "$1"/ -prune -empty)" ]
+directory_empty() {
+    [ -z "$(ls -A "$1/")" ]
 }
 
-function run_as() {
-  if [[ $EUID -eq 0 ]]; then
-    su - www-data -s /bin/bash -c "$1"
+run_as() {
+  if [ "$(id -u)" = 0 ]; then
+    su - www-data -s /bin/sh -c "$1"
   else
-    bash -c "$1"
+    sh -c "$1"
   fi
 }
 
-installed_version="0.0.0~unknown"
+installed_version="0.0.0.0"
 if [ -f /var/www/html/version.php ]; then
-    installed_version=$(php -r 'require "/var/www/html/version.php"; echo implode(".", $OC_Version);')
+    # shellcheck disable=SC2016
+    installed_version="$(php -r 'require "/var/www/html/version.php"; echo implode(".", $OC_Version);')"
 fi
-image_version=$(php -r 'require "/usr/src/nextcloud/version.php"; echo implode(".", $OC_Version);')
+# shellcheck disable=SC2016
+image_version="$(php -r 'require "/usr/src/nextcloud/version.php"; echo implode(".", $OC_Version);')"
 
 if version_greater "$installed_version" "$image_version"; then
     echo "Can't start Nextcloud because the version of the data ($installed_version) is higher than the docker image version ($image_version) and downgrading is not supported. Are you sure you have pulled the newest image version?"
@@ -31,10 +33,10 @@ if version_greater "$installed_version" "$image_version"; then
 fi
 
 if version_greater "$image_version" "$installed_version"; then
-    if [ "$installed_version" != "0.0.0~unknown" ]; then
-        run_as 'php /var/www/html/occ app:list' > /tmp/list_before
+    if [ "$installed_version" != "0.0.0.0" ]; then
+        run_as 'php /var/www/html/occ app:list' | sed -n "/Enabled:/,/Disabled:/p" > /tmp/list_before
     fi
-    if [[ $EUID -eq 0 ]]; then
+    if [ "$(id -u)" = 0 ]; then
       rsync_options="-rlDog --chown www-data:root"
     else
       rsync_options="-rlD"
@@ -42,17 +44,17 @@ if version_greater "$image_version" "$installed_version"; then
     rsync $rsync_options --delete --exclude /config/ --exclude /data/ --exclude /custom_apps/ --exclude /themes/ /usr/src/nextcloud/ /var/www/html/
 
     for dir in config data custom_apps themes; do
-        if [ ! -d /var/www/html/"$dir" ] || directory_empty /var/www/html/"$dir"; then
-            rsync $rsync_options --include /"$dir"/ --exclude '/*' /usr/src/nextcloud/ /var/www/html/
+        if [ ! -d "/var/www/html/$dir" ] || directory_empty "/var/www/html/$dir"; then
+            rsync $rsync_options --include "/$dir/" --exclude '/*' /usr/src/nextcloud/ /var/www/html/
         fi
     done
 
-    if [ "$installed_version" != "0.0.0~unknown" ]; then
+    if [ "$installed_version" != "0.0.0.0" ]; then
         run_as 'php /var/www/html/occ upgrade --no-app-disable'
 
-        run_as 'php /var/www/html/occ app:list' > /tmp/list_after
+        run_as 'php /var/www/html/occ app:list' | sed -n "/Enabled:/,/Disabled:/p" > /tmp/list_after
         echo "The following apps have beed disabled:"
-        diff <(sed -n "/Enabled:/,/Disabled:/p" /tmp/list_before) <(sed -n "/Enabled:/,/Disabled:/p" /tmp/list_after) | grep '<' | cut -d- -f2 | cut -d: -f1
+        diff /tmp/list_before /tmp/list_after | grep '<' | cut -d- -f2 | cut -d: -f1
         rm -f /tmp/list_before /tmp/list_after
     fi
 fi
diff --git a/13.0/fpm-alpine/Dockerfile b/13.0/fpm-alpine/Dockerfile
index 22e24d8f..828be93c 100644
--- a/13.0/fpm-alpine/Dockerfile
+++ b/13.0/fpm-alpine/Dockerfile
@@ -4,8 +4,6 @@ FROM php:7.1-fpm-alpine
 RUN set -ex; \
     \
     apk add --no-cache \
-        bash \
-        coreutils \
         rsync \
     ; \
     \
diff --git a/13.0/fpm-alpine/cron.sh b/13.0/fpm-alpine/cron.sh
index bb65a1fb..4dfa4118 100755
--- a/13.0/fpm-alpine/cron.sh
+++ b/13.0/fpm-alpine/cron.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
-set -e
+#!/bin/sh
+set -eu
 
 exec busybox crond -f -l 0 -L /dev/stdout
diff --git a/13.0/fpm-alpine/entrypoint.sh b/13.0/fpm-alpine/entrypoint.sh
index 0568aac1..8f3ac087 100755
--- a/13.0/fpm-alpine/entrypoint.sh
+++ b/13.0/fpm-alpine/entrypoint.sh
@@ -1,29 +1,31 @@
-#!/bin/bash
-set -e
+#!/bin/sh
+set -eu
 
 # version_greater A B returns whether A > B
-function version_greater() {
-	[[ "$(printf '%s\n' "$@" | sort -V | head -n 1)" != "$1" ]];
+version_greater() {
+	[ "$(printf '%s\n' "$@" | sort -t '.' -n -k1,1 -k2,2 -k3,3 -k4,4 | head -n 1)" != "$1" ]
 }
 
 # return true if specified directory is empty
-function directory_empty() {
-    [ -n "$(find "$1"/ -prune -empty)" ]
+directory_empty() {
+    [ -z "$(ls -A "$1/")" ]
 }
 
-function run_as() {
-  if [[ $EUID -eq 0 ]]; then
-    su - www-data -s /bin/bash -c "$1"
+run_as() {
+  if [ "$(id -u)" = 0 ]; then
+    su - www-data -s /bin/sh -c "$1"
   else
-    bash -c "$1"
+    sh -c "$1"
   fi
 }
 
-installed_version="0.0.0~unknown"
+installed_version="0.0.0.0"
 if [ -f /var/www/html/version.php ]; then
-    installed_version=$(php -r 'require "/var/www/html/version.php"; echo implode(".", $OC_Version);')
+    # shellcheck disable=SC2016
+    installed_version="$(php -r 'require "/var/www/html/version.php"; echo implode(".", $OC_Version);')"
 fi
-image_version=$(php -r 'require "/usr/src/nextcloud/version.php"; echo implode(".", $OC_Version);')
+# shellcheck disable=SC2016
+image_version="$(php -r 'require "/usr/src/nextcloud/version.php"; echo implode(".", $OC_Version);')"
 
 if version_greater "$installed_version" "$image_version"; then
     echo "Can't start Nextcloud because the version of the data ($installed_version) is higher than the docker image version ($image_version) and downgrading is not supported. Are you sure you have pulled the newest image version?"
@@ -31,10 +33,10 @@ if version_greater "$installed_version" "$image_version"; then
 fi
 
 if version_greater "$image_version" "$installed_version"; then
-    if [ "$installed_version" != "0.0.0~unknown" ]; then
-        run_as 'php /var/www/html/occ app:list' > /tmp/list_before
+    if [ "$installed_version" != "0.0.0.0" ]; then
+        run_as 'php /var/www/html/occ app:list' | sed -n "/Enabled:/,/Disabled:/p" > /tmp/list_before
     fi
-    if [[ $EUID -eq 0 ]]; then
+    if [ "$(id -u)" = 0 ]; then
       rsync_options="-rlDog --chown www-data:root"
     else
       rsync_options="-rlD"
@@ -42,17 +44,17 @@ if version_greater "$image_version" "$installed_version"; then
     rsync $rsync_options --delete --exclude /config/ --exclude /data/ --exclude /custom_apps/ --exclude /themes/ /usr/src/nextcloud/ /var/www/html/
 
     for dir in config data custom_apps themes; do
-        if [ ! -d /var/www/html/"$dir" ] || directory_empty /var/www/html/"$dir"; then
-            rsync $rsync_options --include /"$dir"/ --exclude '/*' /usr/src/nextcloud/ /var/www/html/
+        if [ ! -d "/var/www/html/$dir" ] || directory_empty "/var/www/html/$dir"; then
+            rsync $rsync_options --include "/$dir/" --exclude '/*' /usr/src/nextcloud/ /var/www/html/
         fi
     done
 
-    if [ "$installed_version" != "0.0.0~unknown" ]; then
+    if [ "$installed_version" != "0.0.0.0" ]; then
         run_as 'php /var/www/html/occ upgrade --no-app-disable'
 
-        run_as 'php /var/www/html/occ app:list' > /tmp/list_after
+        run_as 'php /var/www/html/occ app:list' | sed -n "/Enabled:/,/Disabled:/p" > /tmp/list_after
         echo "The following apps have beed disabled:"
-        diff <(sed -n "/Enabled:/,/Disabled:/p" /tmp/list_before) <(sed -n "/Enabled:/,/Disabled:/p" /tmp/list_after) | grep '<' | cut -d- -f2 | cut -d: -f1
+        diff /tmp/list_before /tmp/list_after | grep '<' | cut -d- -f2 | cut -d: -f1
         rm -f /tmp/list_before /tmp/list_after
     fi
 fi
diff --git a/13.0/fpm/cron.sh b/13.0/fpm/cron.sh
index bb65a1fb..4dfa4118 100755
--- a/13.0/fpm/cron.sh
+++ b/13.0/fpm/cron.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
-set -e
+#!/bin/sh
+set -eu
 
 exec busybox crond -f -l 0 -L /dev/stdout
diff --git a/13.0/fpm/entrypoint.sh b/13.0/fpm/entrypoint.sh
index 0568aac1..8f3ac087 100755
--- a/13.0/fpm/entrypoint.sh
+++ b/13.0/fpm/entrypoint.sh
@@ -1,29 +1,31 @@
-#!/bin/bash
-set -e
+#!/bin/sh
+set -eu
 
 # version_greater A B returns whether A > B
-function version_greater() {
-	[[ "$(printf '%s\n' "$@" | sort -V | head -n 1)" != "$1" ]];
+version_greater() {
+	[ "$(printf '%s\n' "$@" | sort -t '.' -n -k1,1 -k2,2 -k3,3 -k4,4 | head -n 1)" != "$1" ]
 }
 
 # return true if specified directory is empty
-function directory_empty() {
-    [ -n "$(find "$1"/ -prune -empty)" ]
+directory_empty() {
+    [ -z "$(ls -A "$1/")" ]
 }
 
-function run_as() {
-  if [[ $EUID -eq 0 ]]; then
-    su - www-data -s /bin/bash -c "$1"
+run_as() {
+  if [ "$(id -u)" = 0 ]; then
+    su - www-data -s /bin/sh -c "$1"
   else
-    bash -c "$1"
+    sh -c "$1"
   fi
 }
 
-installed_version="0.0.0~unknown"
+installed_version="0.0.0.0"
 if [ -f /var/www/html/version.php ]; then
-    installed_version=$(php -r 'require "/var/www/html/version.php"; echo implode(".", $OC_Version);')
+    # shellcheck disable=SC2016
+    installed_version="$(php -r 'require "/var/www/html/version.php"; echo implode(".", $OC_Version);')"
 fi
-image_version=$(php -r 'require "/usr/src/nextcloud/version.php"; echo implode(".", $OC_Version);')
+# shellcheck disable=SC2016
+image_version="$(php -r 'require "/usr/src/nextcloud/version.php"; echo implode(".", $OC_Version);')"
 
 if version_greater "$installed_version" "$image_version"; then
     echo "Can't start Nextcloud because the version of the data ($installed_version) is higher than the docker image version ($image_version) and downgrading is not supported. Are you sure you have pulled the newest image version?"
@@ -31,10 +33,10 @@ if version_greater "$installed_version" "$image_version"; then
 fi
 
 if version_greater "$image_version" "$installed_version"; then
-    if [ "$installed_version" != "0.0.0~unknown" ]; then
-        run_as 'php /var/www/html/occ app:list' > /tmp/list_before
+    if [ "$installed_version" != "0.0.0.0" ]; then
+        run_as 'php /var/www/html/occ app:list' | sed -n "/Enabled:/,/Disabled:/p" > /tmp/list_before
     fi
-    if [[ $EUID -eq 0 ]]; then
+    if [ "$(id -u)" = 0 ]; then
       rsync_options="-rlDog --chown www-data:root"
     else
       rsync_options="-rlD"
@@ -42,17 +44,17 @@ if version_greater "$image_version" "$installed_version"; then
     rsync $rsync_options --delete --exclude /config/ --exclude /data/ --exclude /custom_apps/ --exclude /themes/ /usr/src/nextcloud/ /var/www/html/
 
     for dir in config data custom_apps themes; do
-        if [ ! -d /var/www/html/"$dir" ] || directory_empty /var/www/html/"$dir"; then
-            rsync $rsync_options --include /"$dir"/ --exclude '/*' /usr/src/nextcloud/ /var/www/html/
+        if [ ! -d "/var/www/html/$dir" ] || directory_empty "/var/www/html/$dir"; then
+            rsync $rsync_options --include "/$dir/" --exclude '/*' /usr/src/nextcloud/ /var/www/html/
         fi
     done
 
-    if [ "$installed_version" != "0.0.0~unknown" ]; then
+    if [ "$installed_version" != "0.0.0.0" ]; then
         run_as 'php /var/www/html/occ upgrade --no-app-disable'
 
-        run_as 'php /var/www/html/occ app:list' > /tmp/list_after
+        run_as 'php /var/www/html/occ app:list' | sed -n "/Enabled:/,/Disabled:/p" > /tmp/list_after
         echo "The following apps have beed disabled:"
-        diff <(sed -n "/Enabled:/,/Disabled:/p" /tmp/list_before) <(sed -n "/Enabled:/,/Disabled:/p" /tmp/list_after) | grep '<' | cut -d- -f2 | cut -d: -f1
+        diff /tmp/list_before /tmp/list_after | grep '<' | cut -d- -f2 | cut -d: -f1
         rm -f /tmp/list_before /tmp/list_after
     fi
 fi