From 9719e0b772eac7a38e203f4b735e56287edba0ce Mon Sep 17 00:00:00 2001
From: Arturo Rinaldi <arty.net2@gmail.com>
Date: Sun, 24 Jan 2021 17:38:33 +0100
Subject: [PATCH] adding remove and purge macros for APT packages

---
 README.md |  6 ++++++
 build.sh  | 21 +++++++++++++++++++++
 2 files changed, 27 insertions(+)

diff --git a/README.md b/README.md
index 8b7f875af5..0d349a8b63 100644
--- a/README.md
+++ b/README.md
@@ -192,6 +192,12 @@ The following process is followed to build images:
      - **00-packages-nr** - As 00-packages, except these will be installed using
        the ```--no-install-recommends -y``` parameters to apt-get.
 
+     - **00-packages-rm** - As 00-packages, except these will be removed using
+       the ```remove -y``` parameters to apt-get.
+
+     - **00-packages-pr** - As 00-packages, except these will be purged using
+       the ```purge -y``` parameters to apt-get.
+
      - **00-patches** - A directory containing patch files to be applied, using quilt.
        If a file named 'EDIT' is present in the directory, the build process will
        be interrupted with a bash session, allowing an opportunity to create/revise
diff --git a/build.sh b/build.sh
index 6f720b1f50..0401489d1d 100755
--- a/build.sh
+++ b/build.sh
@@ -35,6 +35,27 @@ EOF
 			fi
 			log "End ${SUB_STAGE_DIR}/${i}-packages"
 		fi
+		if [ -f "${i}-packages-rm" ]; then
+			log "Begin ${SUB_STAGE_DIR}/${i}-packages-rm"
+			PACKAGES="$(sed -f "${SCRIPT_DIR}/remove-comments.sed" < "${i}-packages-rm")"
+			if [ -n "$PACKAGES" ]; then
+				on_chroot << EOF
+apt-get -o APT::Acquire::Retries=3 remove -y $PACKAGES
+EOF
+			fi
+			log "End ${SUB_STAGE_DIR}/${i}-packages-rm"
+		fi
+		if [ -f "${i}-packages-pr" ]; then
+Docker can be used to perform the build inside a container. This partially isolates
+			log "Begin ${SUB_STAGE_DIR}/${i}-packages-pr"
+			PACKAGES="$(sed -f "${SCRIPT_DIR}/remove-comments.sed" < "${i}-packages-pr")"
+			if [ -n "$PACKAGES" ]; then
+				on_chroot << EOF
+apt-get -o APT::Acquire::Retries=3 purge -y $PACKAGES
+EOF
+			fi
+			log "End ${SUB_STAGE_DIR}/${i}-packages-pr"
+		fi
 		if [ -d "${i}-patches" ]; then
 			log "Begin ${SUB_STAGE_DIR}/${i}-patches"
 			pushd "${STAGE_WORK_DIR}" > /dev/null