better handle change xlat type

free tmpls, so that the caller doesn't have to do this.

If the tmpl is data, and the new type is XLAT_BOX, then re-initialize
the box from the tmpl data, before freeing the tmpl

Author: alandekok

src/lib/unlang/xlat_alloc.c

@@ -70,11 +70,34 @@ void _xlat_exp_set_type(NDEBUG_LOCATION_ARGS xlat_exp_t *node, xlat_type_t type)
 		TALLOC_FREE(node->group);
 		break;
 
-	case XLAT_FUNC:
 	case XLAT_FUNC_UNRESOLVED:
-		if (type != XLAT_FUNC) {
-			TALLOC_FREE(node->call.args); /* Just switching from unresolved to resolved */
-		} else goto done;
+		if (type == XLAT_FUNC) goto done;  /* Just switching from unresolved to resolved */
+		FALL_THROUGH;
+
+	case XLAT_FUNC:
+		TALLOC_FREE(node->call.args);
+		break;
+
+	case XLAT_TMPL:
+		if (node->vpt && (node->fmt == node->vpt->name)) (void) talloc_steal(node, node->fmt);
+
+		/*
+		 *	Converting a tmpl to a box.  If the tmpl is data, we can then just steal the contents
+		 *	of the box.
+		 */
+		if (type == XLAT_BOX) {
+			tmpl_t *vpt = node->vpt;
+
+			fr_assert(tmpl_rules_cast(vpt) == FR_TYPE_NULL);
+
+			if (tmpl_is_data(vpt)) {
+				fr_value_box_steal(node, &node->data, tmpl_value(vpt));
+			} else {
+				fr_value_box_init_null(&node->data);
+			}
+
+			talloc_free(vpt);
+		}
 		break;
 
 	default:
@@ -171,6 +194,8 @@ xlat_exp_t *_xlat_exp_alloc(NDEBUG_LOCATION_ARGS TALLOC_CTX *ctx, xlat_type_t ty
 				   inlen + extra);
 	_xlat_exp_set_type(NDEBUG_LOCATION_VALS node, type);
 
+	node->quote = T_BARE_WORD; /* ensure that this is always initialized */
+
 	if (type == XLAT_BOX) {
 		node->flags.constant = node->flags.pure = node->flags.can_purify = true;
 	}

src/lib/unlang/xlat_expr.c

@@ -861,9 +861,6 @@ static bool xlat_node_matches_bool(bool *result, xlat_exp_t *parent, xlat_exp_he
 
 	xlat_exp_set_type(parent, XLAT_BOX);
 	fr_value_box_copy(parent, &parent->data, box);
-	parent->flags = (xlat_flags_t) { .pure = true, .constant = true, };
-
-	talloc_free_children(parent);
 
 	return true;
 }
@@ -2694,10 +2691,10 @@ static fr_slen_t tokenize_field(xlat_exp_head_t *head, xlat_exp_t **out, fr_sbuf
 		/*
 		 *	Convert the XLAT_TMPL to XLAT_BOX
 		 */
-		fr_value_box_steal(node, &node->data, tmpl_value(vpt));
-		xlat_exp_set_name_buffer(node, vpt->name);
-		talloc_free(vpt);
+		node->vpt = NULL;
 		xlat_exp_set_type(node, XLAT_BOX);
+		xlat_exp_set_name_buffer(node, vpt->name);
+		fr_value_box_steal(node, &node->data, tmpl_value(vpt));
 		goto done;
 
 	} else if (tmpl_contains_xlat(node->vpt)) {

src/lib/unlang/xlat_purify.c

@@ -146,10 +146,9 @@ static int xlat_purify_list_internal(xlat_exp_head_t *head, request_t *request,
 				 *	wrapper, which ensures that the entire sub-expression results in one
 				 *	output value.
 				 */
-				xlat_exp_set_type(node, XLAT_GROUP);
 				(void) talloc_steal(node, node->vpt->name);
+				xlat_exp_set_type(node, XLAT_GROUP); /* frees node->vpt */
 				(void) talloc_steal(node, xlat);
-				talloc_free(node->vpt);
 				node->group = xlat;
 				break;
 			}

src/lib/unlang/xlat_tokenize.c

@@ -203,13 +203,7 @@ static int xlat_validate_function_arg(xlat_arg_parser_t const *arg_p, xlat_exp_t
 			 *	Raw data can be hoisted to a value-box in this xlat node.
 			 */
 		} else if (tmpl_is_data(node->vpt)) {
-			tmpl_t *vpt = node->vpt;
-
-			fr_assert(tmpl_rules_cast(vpt) == FR_TYPE_NULL);
-
-			fr_value_box_steal(node, &node->data, tmpl_value(vpt));
-			talloc_free(vpt);
-			xlat_exp_set_type(node, XLAT_BOX);
+			xlat_exp_set_type(node, XLAT_BOX); /* also steals the data */
 			fr_value_box_mark_safe_for(&node->data, arg_p->safe_for);
 
 		} else {