fix test

Author: devnexen

Diff for: ext/zend_test/tests/gh17797.phpt

@@ -20,7 +20,7 @@ Warning: require(sumfile.php): Failed to open stream: No such file or directory
 require("sumfile.php");
 ?> on line %d
 
-Fatal error: Uncaught Error: Failed opening required 'sumfile.php' (include_path='.:') in <?php
+Fatal error: Uncaught Error: Failed opening required 'sumfile.php' (include_path='.%s') in <?php
 require("sumfile.php");
 ?>:%d
 Stack trace:

Diff for: main/fopen_wrappers.c

@@ -600,6 +600,9 @@ PHPAPI zend_string *php_resolve_path(const char *filename, size_t filename_lengt
 	 */
 	if (zend_is_executing() &&
 	    (exec_filename = zend_get_executed_filename_ex()) != NULL) {
+		if (ZSTR_LEN(exec_filename) == 0) {
+			return NULL;
+		}
 		const char *exec_fname = ZSTR_VAL(exec_filename);
 		size_t exec_fname_length = ZSTR_LEN(exec_filename) - 1;