[libnftnl PATCH] expr/{masq,nat}: Don't print unused regs

[Phil Sutter <phil@xxxxxx>]

No point in printing the unset register value (which is zero then).

Fixes: af0c182670837 ("expr: masq: Add support for port selection")
Signed-off-by: Phil Sutter <phil@xxxxxx>
---
 src/expr/masq.c | 10 +++++++---
 src/expr/nat.c  | 18 ++++++++++++++----
 2 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/src/expr/masq.c b/src/expr/masq.c
index 622ba282ff160..ea66fecdf2a72 100644
--- a/src/expr/masq.c
+++ b/src/expr/masq.c
@@ -138,9 +138,13 @@ static int nftnl_expr_masq_snprintf_default(char *buf, size_t len,
 	int remain = len, offset = 0, ret = 0;
 
 	if (e->flags & (1 << NFTNL_EXPR_MASQ_REG_PROTO_MIN)) {
-		ret = snprintf(buf, remain,
-			       "proto_min reg %u proto_max reg %u ",
-			       masq->sreg_proto_min, masq->sreg_proto_max);
+		ret = snprintf(buf + offset, remain, "proto_min reg %u ",
+			       masq->sreg_proto_min);
+		SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+	}
+	if (e->flags & (1 << NFTNL_EXPR_MASQ_REG_PROTO_MAX)) {
+		ret = snprintf(buf + offset, remain, "proto_max reg %u ",
+			       masq->sreg_proto_max);
 		SNPRINTF_BUFFER_SIZE(ret, remain, offset);
 	}
 	if (e->flags & (1 << NFTNL_EXPR_MASQ_FLAGS)) {
diff --git a/src/expr/nat.c b/src/expr/nat.c
index 408521626d892..91a1ae6c99a43 100644
--- a/src/expr/nat.c
+++ b/src/expr/nat.c
@@ -236,15 +236,25 @@ nftnl_expr_nat_snprintf_default(char *buf, size_t size,
 
 	if (e->flags & (1 << NFTNL_EXPR_NAT_REG_ADDR_MIN)) {
 		ret = snprintf(buf + offset, remain,
-			       "addr_min reg %u addr_max reg %u ",
-			       nat->sreg_addr_min, nat->sreg_addr_max);
+			       "addr_min reg %u ", nat->sreg_addr_min);
+		SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+	}
+
+	if (e->flags & (1 << NFTNL_EXPR_NAT_REG_ADDR_MAX)) {
+		ret = snprintf(buf + offset, remain,
+			       "addr_max reg %u ", nat->sreg_addr_max);
 		SNPRINTF_BUFFER_SIZE(ret, remain, offset);
 	}
 
 	if (e->flags & (1 << NFTNL_EXPR_NAT_REG_PROTO_MIN)) {
 		ret = snprintf(buf + offset, remain,
-			       "proto_min reg %u proto_max reg %u ",
-			       nat->sreg_proto_min, nat->sreg_proto_max);
+			       "proto_min reg %u ", nat->sreg_proto_min);
+		SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+	}
+
+	if (e->flags & (1 << NFTNL_EXPR_NAT_REG_PROTO_MAX)) {
+		ret = snprintf(buf + offset, remain,
+			       "proto_max reg %u ", nat->sreg_proto_max);
 		SNPRINTF_BUFFER_SIZE(ret, remain, offset);
 	}
 
-- 
2.30.1