Trim the package cache by default, and split it from orphan removal

CleanCache was off, so nothing ever pruned /var/cache/pacman/pkg - 23 GB on the
machine this was found on, with three 3.2 GB copies of one package. Trimming
only drops older versions of installed packages and cached versions of
uninstalled ones, so the cost is downgrade depth, not working software.

flatpak uninstall --unused moves from CleanCache to RemoveOrphans, where it
belongs: unused runtimes are the Flatpak equivalent of orphaned packages, and
removing installed software should not hide behind a flag named for cache
trimming. RemoveOrphans stays off - 'orphaned' only means nothing depends on
it, which is also true of something installed deliberately.

The log now reports what a trim reclaimed, since a real paccache run says
almost nothing and there was otherwise no way to tell it was working.

Makefile

@@ -8,7 +8,7 @@
 # Overridable so a packager can pass the version it is actually building
 # (`make VERSION=$pkgver`). The literal below is the fallback for builds
 # straight from a checkout, and is what a release tag has to carry.
-VERSION      ?= 1.0.4
+VERSION      ?= 1.0.7
 
 PREFIX       ?= /usr
 DESTDIR      ?=

README.md

@@ -55,8 +55,15 @@ business rebuilding somebody's system before being asked.
 | Flatpak | system and per-user installations |
 | AppImages | via [Gear Lever](https://github.com/mijorus/gearlever), if installed |
 
-`-git`/`-devel` AUR packages, cache trimming and orphan removal exist as
-options but are off by default.
+It also trims the pacman package cache after each run (`paccache`, keeping the
+3 most recent versions), because otherwise `/var/cache/pacman/pkg` grows
+forever — tens of gigabytes on a machine with a few large packages. Set
+`KeepOldPackages=1` if disk space matters more than the ability to downgrade.
+
+`-git`/`-devel` AUR packages and orphan removal exist as options but are off by
+default. Orphan removal deletes installed software, and "orphaned" only means
+nothing else depends on it — which is also true of something installed
+deliberately.
 
 ## When it holds back
 

po/cachy-auto-update.pot

@@ -243,3 +243,17 @@ msgstr ""
 
 msgid "pacman's lock file looks left over from an interrupted update. Updates are paused until it is cleared."
 msgstr ""
+
+msgid "Some packages were held back"
+msgstr ""
+
+#, c-format
+msgid "%s could not be updated and was skipped. Everything else is up to date."
+msgstr ""
+
+#, c-format
+msgid "Held back: %s"
+msgstr ""
+
+msgid "The last run was stopped before it finished."
+msgstr ""

po/de.po

@@ -244,3 +244,17 @@ msgstr "Paketdatenbank gesperrt"
 
 msgid "pacman's lock file looks left over from an interrupted update. Updates are paused until it is cleared."
 msgstr "Die Sperrdatei von pacman scheint von einem abgebrochenen Update übrig zu sein. Bis sie entfernt ist, pausieren die Updates."
+
+msgid "Some packages were held back"
+msgstr "Einige Pakete wurden zurückgehalten"
+
+#, c-format
+msgid "%s could not be updated and was skipped. Everything else is up to date."
+msgstr "%s konnte nicht aktualisiert werden und wurde übersprungen. Alles andere ist aktuell."
+
+#, c-format
+msgid "Held back: %s"
+msgstr "Zurückgehalten: %s"
+
+msgid "The last run was stopped before it finished."
+msgstr "Der letzte Lauf wurde abgebrochen, bevor er fertig war."

res/config/cachy-auto-update.conf

@@ -66,16 +66,29 @@ AutoResolveConflicts=yes
 IgnorePkg=
 
 # ---------------------------------------------------------------------------
-# Housekeeping - all off by default
+# Housekeeping
 # ---------------------------------------------------------------------------
 
-# Trim the pacman package cache after an update.
-CleanCache=no
+# Trim the pacman package cache after an update: drop the older versions of
+# installed packages, and every cached version of packages that are no longer
+# installed. Nothing that is currently installed is ever touched, so this only
+# costs the ability to downgrade further back than KeepOldPackages.
+# Without it /var/cache/pacman/pkg grows forever - tens of gigabytes on a
+# machine with a few large packages.
+CleanCache=yes
 
-# How many old versions per package to keep when CleanCache is on.
+# How many old versions per package to keep when CleanCache is on. 3 is the
+# Arch default and leaves room to downgrade. Set it to 1 if disk space matters
+# more than that; on a machine with a handful of multi-gigabyte packages the
+# difference is easily ten gigabytes.
 KeepOldPackages=3
 
-# Remove packages that were installed as dependencies and are no longer needed.
+# Remove packages nothing depends on any more: pacman packages that were pulled
+# in as dependencies and are now unreferenced, plus Flatpak runtimes no
+# installed application uses.
+# Off by default, and unlike CleanCache this one deletes installed software:
+# "orphaned" only means no other package requires it, which is also true of
+# something installed deliberately as a dependency of nothing.
 RemoveOrphans=no
 
 # ---------------------------------------------------------------------------

src/cachy-auto-update-run

@@ -63,6 +63,21 @@ fi
 cau_config_load
 cau_log_open
 
+# Record an interruption rather than leaving the previous run's verdict behind.
+# Without this, killing an interactive run leaves last_result at whatever it was
+# before - so the menu can keep reporting a problem from hours ago while the
+# machine is in fact fully up to date, which is worse than saying nothing.
+# pacman makes the commit phase itself uninterruptible, so the packages either
+# all landed or none did; only our own bookkeeping is at risk here.
+_cau_interrupted() {
+	cau_error "Update run interrupted ($1)"
+	cau_state_write last_result interrupted
+	exit 130
+}
+trap '_cau_interrupted SIGINT'  INT
+trap '_cau_interrupted SIGTERM' TERM
+trap '_cau_interrupted SIGHUP'  HUP
+
 # ---------------------------------------------------------------------------
 # Should this run happen at all?
 # ---------------------------------------------------------------------------
@@ -202,6 +217,22 @@ else
 	fi
 fi
 
+# Packages skipped so the rest of the upgrade could proceed. The notification
+# only fires when the set changes: a blocker waiting on an upstream fix would
+# otherwise produce the same message every single day.
+prev_held="$(cau_state_read held_back '')"
+if [[ -n $CAU_PACMAN_HELD ]]; then
+	cau_state_write held_back "$CAU_PACMAN_HELD"
+	cau_warn "Held back: $CAU_PACMAN_HELD"
+	if [[ $CAU_PACMAN_HELD != "$prev_held" && $CFG_NOTIFY_ERROR == yes ]]; then
+		cau_notify normal "Some packages were held back" \
+			"%s could not be updated and was skipped. Everything else is up to date." \
+			"$CAU_PACMAN_HELD"
+	fi
+else
+	cau_state_clear held_back
+fi
+
 if cau_pacman_reboot_needed; then
 	cau_state_write reboot_needed 1
 	cau_info "A kernel update needs a restart"

src/lib/common.sh

@@ -91,7 +91,14 @@ cau_msg_in() {
 # Output and logging
 # ---------------------------------------------------------------------------
 
-if [[ -t 1 && -z ${NO_COLOR:-} ]]; then
+# Is a person watching? Decided once, here, while stdout is still whatever the
+# process was started with. Testing `-t 1` at the point of use is unreliable:
+# any function called through $(...) or <(...) sees a pipe on stdout and would
+# conclude nobody is there.
+CAU_INTERACTIVE=''
+[[ -t 1 ]] && CAU_INTERACTIVE=1
+
+if [[ -n $CAU_INTERACTIVE && -z ${NO_COLOR:-} ]]; then
 	CAU_C_RESET=$'\033[0m'
 	CAU_C_BOLD=$'\033[1m'
 	CAU_C_DIM=$'\033[2m'
@@ -132,10 +139,19 @@ cau_log_open() {
 	CAU_LOG_OPEN=1
 }
 
-# Runs a command, streaming its combined output into the run log. Returns the
+# Runs a command, capturing its combined output in the run log. Returns the
 # command's exit status.
+#
+# When a person is watching - `cachy-auto-update run` from a terminal - the
+# output is shown as well. Building an AUR package or pulling a few hundred
+# megabytes of Flatpak can take minutes, and silence for that long is
+# indistinguishable from a hang.
 cau_run_logged() {
 	if [[ -n ${CAU_LOG_OPEN:-} ]]; then
+		if [[ -n $CAU_INTERACTIVE ]]; then
+			"$@" 2>&1 | tee -a "$CAU_RUNLOG"
+			return "${PIPESTATUS[0]}"
+		fi
 		"$@" >> "$CAU_RUNLOG" 2>&1
 	else
 		"$@" >&2

src/lib/config.sh

@@ -96,7 +96,7 @@ cau_config_load() {
 	CFG_APPIMAGE=no;              cau_config_bool UpdateAppImages      yes && CFG_APPIMAGE=yes
 	CFG_DEVEL=no;                 cau_config_bool UpdateDevel          no  && CFG_DEVEL=yes
 	CFG_RESOLVE_CONFLICTS=no;     cau_config_bool AutoResolveConflicts yes && CFG_RESOLVE_CONFLICTS=yes
-	CFG_CLEAN_CACHE=no;           cau_config_bool CleanCache           no  && CFG_CLEAN_CACHE=yes
+	CFG_CLEAN_CACHE=no;           cau_config_bool CleanCache           yes && CFG_CLEAN_CACHE=yes
 	CFG_REMOVE_ORPHANS=no;        cau_config_bool RemoveOrphans        no  && CFG_REMOVE_ORPHANS=yes
 	CFG_NOTIFY_SUCCESS=no;        cau_config_bool NotifyOnSuccess      yes && CFG_NOTIFY_SUCCESS=yes
 	CFG_NOTIFY_ERROR=no;          cau_config_bool NotifyOnError        yes && CFG_NOTIFY_ERROR=yes

src/lib/menu.sh

@@ -81,12 +81,23 @@ cau_ui_status() {
 		printf '\n  %s%s%s\n' "$CAU_C_YELLOW" \
 			"$(cau_msg "The last run reported a problem - see 'cachy-auto-update log'.")" \
 			"$CAU_C_RESET"
+	elif [[ $result == interrupted ]]; then
+		printf '\n  %s%s%s\n' "$CAU_C_YELLOW" \
+			"$(cau_msg "The last run was stopped before it finished.")" \
+			"$CAU_C_RESET"
 	fi
 	if [[ $reboot == 1 ]]; then
 		printf '\n  %s%s%s\n' "$CAU_C_YELLOW" \
 			"$(cau_msg "A restart is recommended to finish a kernel update.")" \
 			"$CAU_C_RESET"
 	fi
+
+	local held
+	held="$(cau_state_read held_back '')"
+	if [[ -n $held ]]; then
+		printf '\n  %s%s%s\n' "$CAU_C_YELLOW" \
+			"$(cau_msg "Held back: %s" "$held")" "$CAU_C_RESET"
+	fi
 }
 
 # cau_ui_status_conditions

src/lib/pkg_flatpak.sh

@@ -63,7 +63,10 @@ cau_flatpak_update() {
 		fi
 	done < <(cau_human_users)
 
-	if [[ $CFG_CLEAN_CACHE == yes ]]; then
+	# Unused runtimes are the Flatpak equivalent of orphaned packages - this is
+	# removal of installed software, not cache trimming, so it belongs behind
+	# RemoveOrphans rather than CleanCache.
+	if [[ $CFG_REMOVE_ORPHANS == yes ]]; then
 		cau_run_logged flatpak uninstall --system --unused --noninteractive --assumeyes || true
 	fi
 

src/lib/pkg_pacman.sh

@@ -10,15 +10,40 @@
 CAU_PACMAN_COUNT=0
 CAU_PACMAN_PENDING=''
 
+# Packages that had to be skipped so the rest of the upgrade could go through.
+CAU_PACMAN_HELD=''
+
 # Base flags for every unattended pacman invocation.
 cau_pacman_flags() {
-	printf '%s\n' --noconfirm --color never --noprogressbar --disable-download-timeout
+	printf '%s\n' --noconfirm --color never --disable-download-timeout
+
+	# A progress bar is worth having when somebody is watching a `run` from a
+	# terminal; in the timer's log it is only carriage-return noise.
+	[[ -n $CAU_INTERACTIVE ]] || printf '%s\n' --noprogressbar
+
 	local pkg
 	for pkg in $CFG_IGNORE_PKG; do
 		printf '%s\n' --ignore "$pkg"
 	done
 }
 
+# _cau_pacman_exec <logfile> <pacman args...>
+# Captures pacman's output for classification, and streams it as well when a
+# person is watching. Upgrading a few hundred packages takes minutes; without
+# this an interactive run shows one line and then nothing at all, which is
+# indistinguishable from a hang and invites someone to kill it mid-transaction.
+_cau_pacman_exec() {
+	local log="$1"
+	shift
+
+	if [[ -n $CAU_INTERACTIVE ]]; then
+		pacman "$@" 2>&1 | tee "$log"
+		return "${PIPESTATUS[0]}"
+	fi
+
+	pacman "$@" > "$log" 2>&1
+}
+
 # cau_pacman_pending
 # Fills CAU_PACMAN_PENDING and returns 1 when there is nothing to do.
 cau_pacman_pending() {
@@ -55,6 +80,8 @@ _cau_pacman_classify() {
 
 	if grep -qiE 'are in conflict|unresolvable package conflicts' "$log"; then
 		printf 'conflict\n'
+	elif grep -qiE 'could not satisfy dependencies|breaks dependency|unable to satisfy dependency' "$log"; then
+		printf 'dependency\n'
 	elif grep -qiE 'signature from .* is (unknown trust|marginal trust|invalid)|invalid or corrupted package \(PGP signature\)|key ".*" is unknown|keyring is not writable' "$log"; then
 		printf 'keyring\n'
 	elif grep -qiE 'exists in filesystem' "$log"; then
@@ -64,6 +91,25 @@ _cau_pacman_classify() {
 	fi
 }
 
+# _cau_pacman_blockers <logfile>
+# The packages standing in the way of an otherwise fine upgrade. pacman names
+# them in its dependency errors:
+#
+#   :: removing libperconaserverclient breaks dependency 'libperconaserverclient'
+#      required by heidisql-qt6-bin
+#   :: unable to satisfy dependency 'foo' required by bar
+#
+# In the first form the package being removed is the one to keep; in the second
+# it is the package that cannot be installed.
+_cau_pacman_blockers() {
+	local log="$1"
+
+	{
+		sed -nE "s/.*removing ([^ ]+) breaks dependency.*/\\1/p" "$log"
+		sed -nE "s/.*unable to satisfy dependency '[^']*' required by ([^ ]+).*/\\1/p" "$log"
+	} | grep -E '^[A-Za-z0-9@._+-]+$' | sort -u
+}
+
 # cau_pacman_update
 # Returns 0 on success (including "nothing to do"), 1 on a failure the user
 # needs to hear about. CAU_PACMAN_COUNT holds how many packages moved.
@@ -90,68 +136,92 @@ cau_pacman_update() {
 	mapfile -t flags < <(cau_pacman_flags)
 	log="$(mktemp)" || return 1
 
-	if pacman -Syu "${flags[@]}" > "$log" 2>&1; then
-		cat "$log" >> "$CAU_RUNLOG" 2>/dev/null
-		rm -f "$log"
-		return 0
-	fi
+	# Recovery loop rather than a single retry: fixing one problem regularly
+	# uncovers the next (a conflict resolved into a dependency error, say).
+	# Each remedy is applied at most once, so this always terminates.
+	local -a extra=() blockers=() tried=()
+	local attempt=0 b
 
-	cat "$log" >> "$CAU_RUNLOG" 2>/dev/null
-	kind="$(_cau_pacman_classify "$log")"
-	cau_warn "pacman -Syu failed ($kind)"
-
-	case "$kind" in
-		keyring)
-			# A stale keyring is the one failure that is always safe to fix
-			# automatically, and it blocks everything else until it is.
-			cau_info "Refreshing keyrings and retrying"
-			local -a keyrings=()
-			pacman -Qq archlinux-keyring &> /dev/null && keyrings+=(archlinux-keyring)
-			pacman -Qq cachyos-keyring   &> /dev/null && keyrings+=(cachyos-keyring)
-			if (( ${#keyrings[@]} )); then
-				cau_run_logged pacman -Sy --noconfirm --color never "${keyrings[@]}" || true
-			fi
-			if pacman -Syu "${flags[@]}" > "$log" 2>&1; then
-				cat "$log" >> "$CAU_RUNLOG" 2>/dev/null
-				rm -f "$log"
-				return 0
-			fi
+	while true; do
+		if _cau_pacman_exec "$log" -Syu "${flags[@]}" "${extra[@]}"; then
 			cat "$log" >> "$CAU_RUNLOG" 2>/dev/null
-			;;
-
-		conflict)
-			# A package that has to replace another one. --noconfirm already
-			# answers "Replace X with Y?" affirmatively; what it declines is
-			# ":: X and Y are in conflict. Remove Y? [y/N]". --ask is pacman's
-			# question bitmask: 4 = CONFLICT_PKG, 16 = REMOVE_PKGS.
-			if [[ $CFG_RESOLVE_CONFLICTS != yes ]]; then
-				cau_error "Package conflict requires a decision (AutoResolveConflicts is off)"
-				rm -f "$log"
-				return 1
-			fi
-			cau_info "Resolving package conflicts automatically and retrying"
-			if pacman -Syu "${flags[@]}" --ask=20 > "$log" 2>&1; then
-				cat "$log" >> "$CAU_RUNLOG" 2>/dev/null
-				grep -E '^(removing|replacing) ' "$log" 2>/dev/null \
-					| while read -r line; do cau_info "  $line"; done
-				rm -f "$log"
-				return 0
-			fi
-			cat "$log" >> "$CAU_RUNLOG" 2>/dev/null
-			;;
-
-		filesystem)
-			# Untracked files in the way. Forcing --overwrite here could
-			# silently clobber something the user put there deliberately, so
-			# this one stays a human decision.
-			cau_error "Files on disk conflict with the update; manual review needed"
+			grep -E '^(removing|replacing) ' "$log" 2>/dev/null \
+				| while read -r line; do cau_info "  $line"; done
 			rm -f "$log"
-			return 1
-			;;
-	esac
+			return 0
+		fi
+
+		cat "$log" >> "$CAU_RUNLOG" 2>/dev/null
+		kind="$(_cau_pacman_classify "$log")"
+		cau_warn "pacman -Syu failed ($kind)"
+
+		if (( ++attempt > 3 )) || [[ " ${tried[*]} " == *" $kind "* ]]; then
+			break
+		fi
+		tried+=("$kind")
+
+		case "$kind" in
+			keyring)
+				# A stale keyring is the one failure that is always safe to fix
+				# automatically, and it blocks everything else until it is.
+				cau_info "Refreshing keyrings and retrying"
+				local -a keyrings=()
+				pacman -Qq archlinux-keyring &> /dev/null && keyrings+=(archlinux-keyring)
+				pacman -Qq cachyos-keyring   &> /dev/null && keyrings+=(cachyos-keyring)
+				if (( ${#keyrings[@]} )); then
+					cau_run_logged pacman -Sy --noconfirm --color never "${keyrings[@]}" || true
+				fi
+				;;
+
+			conflict)
+				# A package that has to replace another one. --noconfirm already
+				# answers "Replace X with Y?" affirmatively; what it declines is
+				# ":: X and Y are in conflict. Remove Y? [y/N]". --ask is pacman's
+				# question bitmask: 4 = CONFLICT_PKG, 16 = REMOVE_PKGS.
+				if [[ $CFG_RESOLVE_CONFLICTS != yes ]]; then
+					cau_error "Package conflict requires a decision (AutoResolveConflicts is off)"
+					break
+				fi
+				cau_info "Resolving package conflicts automatically and retrying"
+				extra+=(--ask=20)
+				;;
+
+			dependency)
+				# Something installed still depends on a package the repos want
+				# to drop or replace - almost always an AUR package that has not
+				# caught up yet. Nothing here can fix that, and it is not worth
+				# failing over: letting one stuck package block every other
+				# update indefinitely is far worse on an unattended machine.
+				# Hold the blockers back and upgrade everything else.
+				mapfile -t blockers < <(_cau_pacman_blockers "$log")
+				if (( ${#blockers[@]} == 0 )); then
+					cau_error "Dependency problem with no package to hold back"
+					break
+				fi
+				for b in "${blockers[@]}"; do
+					extra+=(--ignore "$b")
+				done
+				CAU_PACMAN_HELD="${blockers[*]}"
+				cau_warn "Holding back ${blockers[*]} and retrying without them"
+				;;
+
+			filesystem)
+				# Untracked files in the way. Forcing --overwrite here could
+				# silently clobber something the user put there deliberately, so
+				# this one stays a human decision.
+				cau_error "Files on disk conflict with the update; manual review needed"
+				break
+				;;
+
+			*)
+				break
+				;;
+		esac
+	done
 
 	rm -f "$log"
 	CAU_PACMAN_COUNT=0
+	CAU_PACMAN_HELD=''
 	return 1
 }
 
@@ -184,7 +254,14 @@ cau_pacman_cleanup() {
 	fi
 
 	if [[ $CFG_CLEAN_CACHE == yes ]] && cau_have paccache; then
-		cau_info "Trimming the package cache"
+		# paccache's dry run reports what a real run would reclaim; logging it
+		# first is the only way to tell afterwards whether trimming is doing
+		# anything, since the real run says little.
+		local reclaim
+		reclaim="$( { paccache -d --nocolor -k"$CFG_KEEP_OLD"; paccache -du --nocolor -k0; } 2>&1 \
+			| grep -oE 'disk space saved: [^)]*' | paste -sd', ' -)"
+
+		cau_info "Trimming the package cache (keeping $CFG_KEEP_OLD old version(s))${reclaim:+ - $reclaim}"
 		cau_run_logged paccache -r --nocolor -k"$CFG_KEEP_OLD"  || cau_warn "paccache -r failed"
 		cau_run_logged paccache -ru --nocolor -k0               || cau_warn "paccache -ru failed"
 	fi