Experimental support for `apt-listbugs` during downloads

You have to explicitly enable it though

2 files changed, 28 insertions, 18 deletions

diff --git a/README.md b/README.md
index 7f0062b..432bd34 100644
--- a/README.md
+++ b/README.md
@@ -36,31 +36,21 @@ Similarly, systemd is normally notified on `make uninstall`, but again if
 `DESTDIR` is set and different from `PREFIX`, the steps are omitted again.
 
 
-## TODO
-
-### apt-listbugs
+## apt-listbugs
 
 We disable `apt-listbugs` during upgrades, because desktop systems typically use
 `NetworkManager`, which is not started by default for `offline-updates.target`.
 And if `apt-listbugs` can't reach the network, it aborts the upgrade.
 
-We could try pulling in the network during upgrades, just in case `apt-listbugs`
-is installed. But that kind of defeats the purpose of "offline updates". Also,
-it's redundant if `apt-listbugs` isn't installed. And given that this package's
-target audience is mainly systems that are *not* individually managed by
-attentive sysadmins, but are as much as possible fire-and-forget, "stable"/LTS
-systems for users who aren't necessarily in a position to make a decision on
-whether a bug will affect their workflow, the intersection of those systems with
-`apt-desktop-upgrades` installed, and those with `apt-listbugs` installed, is
-probably pretty small.
+There is experimental functionality for checking `apt-listbugs` (if it is
+installed) during the updating/downloading packages phase. If any bugs are found
+for any of the packages to be upgraded, then an upgrade is not scheduled (and if
+one already is, it is cancelled).
 
-However...
+To enable this functionality, set `CHECK_LISTBUGS=true` in `adu-download`.
 
-It would be nice if it were possible somehow to hook `apt-listbugs` (if it's
-installed) into the `adu-download` phase of things, and just not download
-updates for packages which have bugs (or remove already-downloaded updates).
 
-So, look into a way of doing that.
+## TODO
 
 ### Notifying users about updates
 
diff --git a/adu-download b/adu-download
index c97d6e8..9fcf505 100755
--- a/adu-download
+++ b/adu-download
@@ -20,6 +20,8 @@
 
 set -e
 
+CHECK_LISTBUGS=false
+
 SBINDIR=/usr/local/sbin
 
 UPDATE_SYMLINK="/system-update"
@@ -27,11 +29,29 @@ UPDATE_TARGET="${SBINDIR}/adu-upgrade"
 
 apt-get -qq update
 
-upgrades=$(apt -qq list --upgradeable 2>/dev/null | wc -l)
+upgradeable=$(apt -qq list --upgradeable 2>/dev/null)
+upgrades=$(echo "$upgradeable" | wc -l)
 if [ "$upgrades" -eq 0 ]; then
 	exit 0
 fi
 
+if $CHECK_LISTBUGS && command -v apt-listbugs >/dev/null; then
+	# Sed script to change format of `apt list --upgradeable` to `apt-listbugs`
+	#sed_upg_lb='s:^\([^/]\+\)/[^ ]\+ \([^ ]\+\) .*:\1:'
+	sed_upg_lb='s:^\([^/]\+\)/[^ ]\+ \([^ ]\+\) .*:\1/\2:'
+
+	#echo "Checking for bugs in: $(echo "$upgradeable" | sed -e "$sed_upg_lb")"
+	bugs=$(echo "$upgradeable" | sed -e "$sed_upg_lb" | xargs apt-listbugs -q list | grep -E -- "- #[[:digit:]]+ -")
+	if [ -n "$bugs" ]; then
+		#echo "$bugs"
+		echo "$upgrades upgrades available, but $(echo "$bugs" | wc -l) bugs exist - ignoring upgrade"
+		if [ x"$(realpath -- "${UPDATE_SYMLINK}")" = x"${UPDATE_TARGET}" ]; then
+			rm -f -- "${UPDATE_SYMLINK}"
+		fi
+		exit 0
+	fi
+fi
+
 apt-get -q -y --with-new-pkgs --download-only upgrade | grep "^Get:" | cat
 
 ln -s -- "${UPDATE_TARGET}" "${UPDATE_SYMLINK}" 2>/dev/null || true