stagefiles: guard unnecessary chroot removal

just as most scripts are skipped if their stagefile exists (indicating
that they have already been run to completion), including chroot
preparation scripts in install mode, this implements the same guard for
chroot prep remove mode, such that they exit early if their stagefile
does not exist, indicating that the modification has already been removed.
(also override-able by --force in the same way).

this basically just uses a tweaked copy of Check_stagefile().

Gbp-Dch: Short

functions/stagefile.sh

@@ -27,10 +27,8 @@ Check_stagefile ()
 	NAME="$(basename ${FILE})"
 
 	# Checking stage file
-	if [ -f "${FILE}" ]
-	then
-		if [ "${_FORCE}" != "true" ]
-		then
+	if [ -f "${FILE}" ]; then
+		if [ "${_FORCE}" != "true" ]; then
 			# Skip execution
 			Echo_warning "Skipping %s, already done" "${NAME}"
 			exit 0
@@ -42,6 +40,27 @@ Check_stagefile ()
 	fi
 }
 
+# Used by chroot preperation scripts in removal mode
+Ensure_stagefile_exists ()
+{
+	local FILE
+	local NAME
+	FILE=".build/${1:-$(Stagefile_name)}"
+	NAME="$(basename ${FILE})"
+
+	# Checking stage file
+	if [ ! -f "${FILE}" ]; then
+		if [ "${_FORCE}" != "true" ]; then
+			# Skip execution
+			Echo_warning "Skipping removal of %s, it is not applied" "${NAME}"
+			exit 0
+		else
+			# Force execution
+			Echo_message "Forcing %s" "${NAME}"
+		fi
+	fi
+}
+
 Create_stagefile ()
 {
 	local FILE

scripts/build/chroot_apt

@@ -147,6 +147,9 @@ case "${1}" in
 	remove)
 		Echo_message "Deconfiguring file /etc/apt/apt.conf"
 
+		# Checking stage file
+		Ensure_stagefile_exists
+
 		# Acquire lock file
 		Acquire_lockfile
 

scripts/build/chroot_debianchroot

@@ -50,6 +50,9 @@ case "${1}" in
 	remove)
 		Echo_message "Deconfiguring file /etc/debian_chroot"
 
+		# Checking stage file
+		Ensure_stagefile_exists
+
 		# Acquire lock file
 		Acquire_lockfile
 

scripts/build/chroot_devpts

@@ -47,6 +47,9 @@ case "${1}" in
 	remove)
 		Echo_message "Begin unmounting /dev/pts..."
 
+		# Checking stage file
+		Ensure_stagefile_exists
+
 		# Acquire lock file
 		Acquire_lockfile
 

scripts/build/chroot_dpkg

@@ -60,6 +60,9 @@ EOF
 	remove)
 		Echo_message "Deconfiguring file /sbin/start-stop-daemon"
 
+		# Checking stage file
+		Ensure_stagefile_exists
+
 		# Acquire lock file
 		Acquire_lockfile
 

scripts/build/chroot_hostname

@@ -57,6 +57,9 @@ EOF
 	remove)
 		Echo_message "Deconfiguring file /etc/hostname"
 
+		# Checking stage file
+		Ensure_stagefile_exists
+
 		# Acquire lock file
 		Acquire_lockfile
 

scripts/build/chroot_hosts

@@ -61,6 +61,9 @@ EOF
 	remove)
 		Echo_message "Deconfiguring file /etc/hosts"
 
+		# Checking stage file
+		Ensure_stagefile_exists
+
 		# Acquire lock file
 		Acquire_lockfile
 

scripts/build/chroot_proc

@@ -47,6 +47,9 @@ case "${1}" in
 	remove)
 		Echo_message "Begin unmounting /proc..."
 
+		# Checking stage file
+		Ensure_stagefile_exists
+
 		# Acquire lock file
 		Acquire_lockfile
 

scripts/build/chroot_resolv

@@ -64,6 +64,9 @@ case "${1}" in
 	remove)
 		Echo_message "Deconfiguring file /etc/resolv.conf"
 
+		# Checking stage file
+		Ensure_stagefile_exists
+
 		# Acquire lock file
 		Acquire_lockfile
 

scripts/build/chroot_selinuxfs

@@ -50,6 +50,9 @@ case "${1}" in
 	remove)
 		Echo_message "Begin unmounting /sys/fs/selinux..."
 
+		# Checking stage file
+		Ensure_stagefile_exists
+
 		# Acquire lock file
 		Acquire_lockfile
 

scripts/build/chroot_sysfs

@@ -47,6 +47,9 @@ case "${1}" in
 	remove)
 		Echo_message "Begin unmounting /sys..."
 
+		# Checking stage file
+		Ensure_stagefile_exists
+
 		# Acquire lock file
 		Acquire_lockfile
 

scripts/build/chroot_sysv-rc

@@ -56,6 +56,9 @@ EOF
 	remove)
 		Echo_message "Deconfiguring file /usr/sbin/policy-rc.d"
 
+		# Checking stage file
+		Ensure_stagefile_exists
+
 		# Acquire lock file
 		Acquire_lockfile
 

scripts/build/chroot_tmpfs

@@ -52,6 +52,9 @@ case "${1}" in
 	remove)
 		Echo_message "Deconfiguring tmpfs for /var/lib/dpkg"
 
+		# Checking stage file
+		Ensure_stagefile_exists
+
 		# Acquire lock file
 		Acquire_lockfile