Allow exceptions in __toString()

RFC: https://wiki.php.net/rfc/tostring_exceptions

And convert some object to string conversion related recoverable
fatal errors into Error exceptions.

Improve exception safety of internal code performing string
conversions.

2 files changed, 13 insertions, 2 deletions

diff --git a/ext/mysqli/mysqli.c b/ext/mysqli/mysqli.c
index 394a838512..9964ea0be4 100644
--- a/ext/mysqli/mysqli.c
+++ b/ext/mysqli/mysqli.c
@@ -309,6 +309,9 @@ zval *mysqli_read_property(zval *object, zval *member, int type, void **cache_sl
 	if (Z_TYPE_P(member) != IS_STRING) {
 		ZVAL_STR(&tmp_member, zval_get_string_func(member));
 		member = &tmp_member;
+		if (EG(exception)) {
+			return &EG(uninitialized_zval);
+		}
 	}
 
 	if (obj->prop_handler != NULL) {
@@ -342,6 +345,9 @@ zval *mysqli_write_property(zval *object, zval *member, zval *value, void **cach
 	if (Z_TYPE_P(member) != IS_STRING) {
 		ZVAL_STR(&tmp_member, zval_get_string_func(member));
 		member = &tmp_member;
+		if (EG(exception)) {
+			return value;
+		}
 	}
 
 	obj = Z_MYSQLI_P(object);
diff --git a/ext/mysqli/mysqli_api.c b/ext/mysqli/mysqli_api.c
index 1a7303c987..13d21e9312 100644
--- a/ext/mysqli/mysqli_api.c
+++ b/ext/mysqli/mysqli_api.c
@@ -899,7 +899,10 @@ PHP_FUNCTION(mysqli_stmt_execute)
 			if (!(stmt->param.is_null[i] = (Z_ISNULL_P(param)))) {
 				switch (stmt->stmt->params[i].buffer_type) {
 					case MYSQL_TYPE_VAR_STRING:
-						convert_to_string_ex(param);
+						if (!try_convert_to_string(param)) {
+							return;
+						}
+
 						stmt->stmt->params[i].buffer = Z_STRVAL_P(param);
 						stmt->stmt->params[i].buffer_length = Z_STRLEN_P(param);
 						break;
@@ -1781,7 +1784,9 @@ PHP_FUNCTION(mysqli_options)
 	if (expected_type != Z_TYPE_P(mysql_value)) {
 		switch (expected_type) {
 			case IS_STRING:
-				convert_to_string_ex(mysql_value);
+				if (!try_convert_to_string(mysql_value)) {
+					return;
+				}
 				break;
 			case IS_LONG:
 				convert_to_long_ex(mysql_value);