check that all cached packages exist before trying to extract anything

This might be a slight slowdown because of reduced parallelism, but it
makes the user experience nicer, improved diagnostics, and avoids a common
case where it runs for a long time before failing (fail early).

1 files changed, 19 insertions, 5 deletions

diff --git a/pristine-etc-keeper b/pristine-etc-keeper
index a6a395c..a8a3954 100755
--- a/pristine-etc-keeper
+++ b/pristine-etc-keeper
@@ -26,10 +26,24 @@ commit() (
 
 	rm -rf etc/
 
+	local err=false
+	local files=()
 	while IFS=' ' read -r pkgname pkgver arch; do
-		file=("/var/cache/pacman/pkg/$pkgname-$pkgver-$arch".pkg.tar.*)
-		bsdtar xpfv "$file" etc
+		local file=("/var/cache/pacman/pkg/$pkgname-$pkgver-$arch".pkg.tar.*)
+		if ! test -f "$file"; then
+			printf "ERROR: no cached package for %s %s %s\n" "$pkgname" "$pkgver" "$arch"
+			err=true
+		fi
+		files+=("$file")
 	done < <(join <(pacman-etc-name-ver|sort) <(pacman-all-name-arch|sort))
+	if $err; then
+		return 1
+	fi
+	local file
+	for file in "${files[@]}"; do
+		printf " -> %s\n" "$file"
+		bsdtar xpvf "$file" etc
+	done
 
 	touch etc/.gitignore
 	ln -sr etc.git etc/.git
@@ -68,14 +82,14 @@ main() {
 	while true; do
 		lock
 		if ! [[ -f /var/lib/pristine-etc/spool ]]; then
-			exit 0
+			return 0
 		fi
 		msg="$(cat /var/lib/pristine-etc/spool)"
 		rm -f /var/lib/pristine-etc/spool
 		unlock
 
-		commit "$msg"
-		pull
+		commit "$msg" || return $?
+		pull || return $?
 	done
 }