makepkg: Use read to parse status file during signature verification.

Instead of invoking grep multiple times, parse the status file once.

This refactoring also changes the behvaiour when signature verification
fails due to a missing public key: It is now an error instead of a
warning.

Signed-off-by: Allan McRae <allan@archlinux.org>

scripts/makepkg.sh.in

@@ -1244,13 +1244,56 @@ check_checksums() {
 	fi
 }
 
+parse_gpg_statusfile() {
+	local type arg1 arg6
+
+	while read -r _ type arg1 _ _ _ _ arg6 _; do
+		case "$type" in
+			GOODSIG)
+				pubkey=$arg1
+				success=1
+				status="good"
+				;;
+			EXPSIG)
+				pubkey=$arg1
+				success=1
+				status="expired"
+				;;
+			EXPKEYSIG)
+				pubkey=$arg1
+				success=1
+				status="expiredkey"
+				;;
+			REVKEYSIG)
+				pubkey=$arg1
+				success=0
+				status="revokedkey"
+				;;
+			BADSIG)
+				pubkey=$arg1
+				success=0
+				status="bad"
+				;;
+			ERRSIG)
+				pubkey=$arg1
+				success=0
+				if [[ $arg6 == 9 ]]; then
+					status="missingkey"
+				else
+					status="error"
+				fi
+				;;
+		esac
+	done < "$1"
+}
+
 check_pgpsigs() {
 	(( SKIPPGPCHECK )) && return 0
 	! source_has_signatures && return 0
 
 	msg "$(gettext "Verifying source file signatures with %s...")" "gpg"
 
-	local file pubkey ext decompress found
+	local file ext decompress found pubkey success status
 	local warning=0
 	local errors=0
 	local statusfile=$(mktemp)
@@ -1292,31 +1335,43 @@ check_pgpsigs() {
 			"")  decompress="cat" ;;
 		esac
 
-		if ! $decompress < "$sourcefile" | gpg --quiet --batch --status-file "$statusfile" --verify "$file" - 2> /dev/null; then
+		$decompress < "$sourcefile" | gpg --quiet --batch --status-file "$statusfile" --verify "$file" - 2> /dev/null
+		# these variables are assigned values in parse_gpg_statusfile
+		success=0
+		status=
+		pubkey=
+		parse_gpg_statusfile "$statusfile"
+		if (( ! $success )); then
 			printf '%s' "$(gettext "FAILED")" >&2
-			if ! pubkey=$(awk '/NO_PUBKEY/ { print $3; exit 1; }' "$statusfile"); then
+			case "$status" in
+				"missingkey")
 					printf ' (%s)' "$(gettext "unknown public key") $pubkey" >&2
-				warnings=1
+					;;
-			else
+				"revokedkey")
-				errors=1
+					printf " ($(gettext "public key %s has been revoked"))" "$pubkey" >&2
-			fi
+					;;
-			printf '\n' >&2
+				"bad")
-		else
+					printf ' (%s)' "$(gettext "bad signature from public key") $pubkey" >&2
-			if grep -q "REVKEYSIG" "$statusfile"; then
+					;;
-				printf '%s (%s)' "$(gettext "FAILED")" "$(gettext "the key has been revoked.")" >&2
+				"error")
+					printf ' (%s)' "$(gettext "error during signature verification")" >&2
+					;;
+			esac
 			errors=1
 		else
 			printf '%s' "$(gettext "Passed")" >&2
-				if grep -q "EXPSIG" "$statusfile"; then
+			case "$status" in
+				"expired")
 					printf ' (%s)' "$(gettext "WARNING:") $(gettext "the signature has expired.")" >&2
 					warnings=1
-				elif grep -q "EXPKEYSIG" "$statusfile"; then
+					;;
+				"expiredkey")
 					printf ' (%s)' "$(gettext "WARNING:") $(gettext "the key has expired.")" >&2
 					warnings=1
-				fi
+					;;
+			esac
 		fi
 		printf '\n' >&2
-		fi
 	done
 
 	rm -f "$statusfile"