[PATCH nft 1/4] evaluate: New internal helper __expr_evaluate_range

[Florian Westphal <fw@strlen.de>]

From: Ander Juaristi <a@juaristi.eus>

This is used by the followup patch to evaluate a range without emitting
an error when the left value is larger than the right one.

This is done to handle time-matching such as
23:00-01:00 -- expr_evaluate_range() will reject this, but
we want to be able to evaluate and then handle this as a request
to match from 23:00 to 1am.

Signed-off-by: Ander Juaristi <a@juaristi.eus>
Signed-off-by: Florian Westphal <fw@strlen.de>
---
 src/evaluate.c | 20 ++++++++++++++++----
 1 file changed, 16 insertions(+), 4 deletions(-)

diff --git a/src/evaluate.c b/src/evaluate.c
index 831eb7c25c5c..a707f5e7e1fb 100755
--- a/src/evaluate.c
+++ b/src/evaluate.c
@@ -941,16 +941,28 @@ static int expr_evaluate_range_expr(struct eval_ctx *ctx,
 	return 0;
 }
 
-static int expr_evaluate_range(struct eval_ctx *ctx, struct expr **expr)
+static int __expr_evaluate_range(struct eval_ctx *ctx, struct expr **expr)
 {
-	struct expr *range = *expr, *left, *right;
+	struct expr *range = *expr;
 
 	if (expr_evaluate_range_expr(ctx, range, &range->left) < 0)
 		return -1;
-	left = range->left;
-
 	if (expr_evaluate_range_expr(ctx, range, &range->right) < 0)
 		return -1;
+
+	return 0;
+}
+
+static int expr_evaluate_range(struct eval_ctx *ctx, struct expr **expr)
+{
+	struct expr *range = *expr, *left, *right;
+	int rc;
+
+	rc = __expr_evaluate_range(ctx, expr);
+	if (rc)
+		return rc;
+
+	left = range->left;
 	right = range->right;
 
 	if (mpz_cmp(left->value, right->value) >= 0)
-- 
2.21.0