Revise a couple of uses of FR_TYPE_STRUCTURAL

FR_TYPE_STRUCTURAL has a name of the same form as the values of
fr_type_t, but is carefully #defined so it can appear in a switch
statement looking like a single value but underneath expanding to
multiple cases, making some of its uses counterintuitive.

src/lib/util/dict_util.c

@@ -1114,40 +1114,17 @@ int dict_attr_child_add(fr_dict_attr_t *parent, fr_dict_attr_t *child)
 	 *	Attributes are inserted into the bin in order of their attribute
 	 *	numbers to allow slightly more efficient lookups.
 	 */
-	bin = &children[child->attr & 0xff];
-	for (;;) {
-		bool child_is_struct = false;
-		bool bin_is_struct = false;
-
-		if (!*bin) break;
-
+	for (bin = &children[child->attr & 0xff]; *bin; bin = &(*bin)->next) {
 		/*
 		 *	Workaround for vendors that overload the RFC space.
 		 *	Structural attributes always take priority.
 		 */
-		switch (child->type) {
-		case FR_TYPE_STRUCTURAL:
-			child_is_struct = true;
-			break;
-
-		default:
-			break;
-		}
-
-		switch ((*bin)->type) {
-		case FR_TYPE_STRUCTURAL:
-			bin_is_struct = true;
-			break;
-
-		default:
-			break;
-		}
+		bool child_is_struct = fr_type_is_structural(child->type);
+		bool bin_is_struct = fr_type_is_structural((*bin)->type);
 
 		if (child_is_struct && !bin_is_struct) break;
-		else if (fr_dict_vendor_num_by_da(child) <= fr_dict_vendor_num_by_da(*bin)) break;	/* Prioritise RFC attributes */
-		else if (child->attr <= (*bin)->attr) break;
-
-		bin = &(*bin)->next;
+		if (fr_dict_vendor_num_by_da(child) <= fr_dict_vendor_num_by_da(*bin)) break;	/* Prioritise RFC attributes */
+		if (child->attr <= (*bin)->attr) break;
 	}
 
 	memcpy(&this, &bin, sizeof(this));

src/lib/util/types.h

@@ -217,6 +217,19 @@ typedef enum {
 	_mid(FR_TYPE_TLV) \
 	_end(FR_TYPE_VENDOR)
 
+/** Hack for truthiness check
+ *
+ * - VSAs
+ * - Structs
+ * - TLVs
+ * - Vendors
+ */
+#define FR_TYPE_STRUCTURAL_EXCEPT_GROUP_DEF(_beg, _mid, _end) \
+	_beg(FR_TYPE_VSA) \
+	_mid(FR_TYPE_STRUCT) \
+	_mid(FR_TYPE_TLV) \
+	_end(FR_TYPE_VENDOR)
+
 /** Match all non value types in case statements
  *
  * - Groups
@@ -279,6 +292,7 @@ typedef enum {
 #define FR_TYPE_QUOTED				FR_TYPE_QUOTED_DEF(CASE_BEG, CASE_MID, CASE_END)
 
 #define FR_TYPE_STRUCTURAL_EXCEPT_VSA		FR_TYPE_STRUCTURAL_EXCEPT_VSA_DEF(CASE_BEG, CASE_MID, CASE_END)
+#define FR_TYPE_STRUCTURAL_EXCEPT_GROUP		FR_TYPE_STRUCTURAL_EXCEPT_GROUP_DEF(CASE_BEG, CASE_MID, CASE_END)
 #define FR_TYPE_STRUCTURAL			FR_TYPE_STRUCTURAL_DEF(CASE_BEG, CASE_MID, CASE_END)
 #define FR_TYPE_LEAF				FR_TYPE_LEAF_DEF(CASE_BEG, CASE_MID, CASE_END)
 #define FR_TYPE_NON_LEAF			FR_TYPE_NON_LEAF_DEF(CASE_BEG, CASE_MID, CASE_END)

src/lib/util/value.c

@@ -6063,11 +6063,11 @@ bool fr_value_box_is_truthy(fr_value_box_t const *in)
 
 	switch (in->type) {
 	case FR_TYPE_NULL:
+	case FR_TYPE_STRUCTURAL_EXCEPT_GROUP:
 		return false;
 
-	case FR_TYPE_STRUCTURAL:
-		if (in->type == FR_TYPE_GROUP) return (fr_value_box_list_num_elements(&in->vb_group) > 0);
-		return false;
+	case FR_TYPE_GROUP:
+		return (fr_value_box_list_num_elements(&in->vb_group) > 0);
 
 	case FR_TYPE_BOOL:
 		return in->vb_bool;