expr: Introduce nftnl_expr_fprintf()

Implement expression printing into a FILE pointer analogous to
nftnl_rule_fprintf().

Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

2 files changed, 18 insertions, 0 deletions

diff --git a/src/expr.c b/src/expr.c
index c5fcf06..1eae707 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -293,3 +293,17 @@ int nftnl_expr_snprintf(char *buf, size_t size, const struct nftnl_expr *expr,
 	return offset;
 }
 EXPORT_SYMBOL(nftnl_expr_snprintf);
+
+static int nftnl_expr_do_snprintf(char *buf, size_t size, const void *e,
+				  uint32_t cmd, uint32_t type, uint32_t flags)
+{
+	return nftnl_expr_snprintf(buf, size, e, type, flags);
+}
+
+int nftnl_expr_fprintf(FILE *fp, const struct nftnl_expr *expr, uint32_t type,
+		       uint32_t flags)
+{
+	return nftnl_fprintf(fp, expr, NFTNL_CMD_UNSPEC, type, flags,
+			     nftnl_expr_do_snprintf);
+}
+EXPORT_SYMBOL(nftnl_expr_fprintf);
diff --git a/src/libnftnl.map b/src/libnftnl.map
index 1892c98..d59e802 100644
--- a/src/libnftnl.map
+++ b/src/libnftnl.map
@@ -307,3 +307,7 @@ global:
 
 local: *;
 };
+
+LIBNFTNL_6 {
+  nftnl_expr_fprintf;
+} LIBNFTNL_5;