From: Andre Noll <maan@tuebingen.mpg.de>
Date: Wed, 6 Feb 2019 17:49:06 +0000 (+0100)
Subject: Improve diagnostics of lls_check_arg_count().
X-Git-Tag: v1.0.3~1^3
X-Git-Url: http://git.tuebingen.mpg.de/?p=lopsub.git;a=commitdiff_plain;h=4636c7a90e91633d0196860f5f5531a633f782b7;hp=-c

Improve diagnostics of lls_check_arg_count().

The old code could return an error message like

	at least 1 non-option args required, 0 given

even if exactly 1 arg is required. So check this case and print

	exactly 1 non-option args required, 0 given

instead. The check for the upper bound has the same issue. It is
considered a bug in the application if min_argc > max_argc, so check
for this case as well.
---

4636c7a90e91633d0196860f5f5531a633f782b7
diff --git a/lopsub.c b/lopsub.c
index 44abc93..d495663 100644
--- a/lopsub.c
+++ b/lopsub.c
@@ -724,9 +724,11 @@ int lls_check_arg_count(const struct lls_parse_result *lpr,
 {
 	if (errctx)
 		*errctx = NULL;
+	assert(min_argc <= max_argc);
 	if (lpr->num_inputs < min_argc) {
-		xasprintf(errctx, "at least %u non-option args required, "
-			"%u given", min_argc, lpr->num_inputs);
+		xasprintf(errctx, "%s %u non-option args required, %u given",
+			min_argc < max_argc? "at least" : "exactly",
+			min_argc, lpr->num_inputs);
 		return -E_LLS_BAD_ARG_COUNT;
 	}
 	if (lpr->num_inputs > max_argc) {
@@ -734,8 +736,10 @@ int lls_check_arg_count(const struct lls_parse_result *lpr,
 			xasprintf(errctx, "no non-option args allowed, "
 				"%u given", lpr->num_inputs);
 		else
-			xasprintf(errctx, "at most %u non-option args allowed, "
-				"%u given", max_argc, lpr->num_inputs);
+			xasprintf(errctx, "%s %u non-option args allowed, "
+				"%u given", min_argc < max_argc?
+				"at most" : "exactly",
+				max_argc, lpr->num_inputs);
 		return -E_LLS_BAD_ARG_COUNT;
 	}
 	return 1;