message: fix \0 terminal bug
diff: @@ -1224,7 +1224,7 @@ static CPINLINE void swoole_string_release(zend_string *str)
  ZSTR_ALLOCA_FREE(str, 0);
  }
  -static CPINLINE zend_class_entry* swoole_try_get_ce(zend_string *class_name)
  +static zend_class_entry* swoole_try_get_ce(zend_string *class_name)
  {
  //user class , do not support incomplete class now
  zend_class_entry *ce = zend_lookup_class(class_name);
  @@ -1234,6 +1234,14 @@ static CPINLINE zend_class_entry* swoole_try_get_ce(zend_string *class_name)
  }
  // try call unserialize callback and retry lookup
  zval user_func, args[1], retval;
  +
  + /* Check for unserialize callback */
  + if ((PG(unserialize_callback_func) == NULL) || (PG(unserialize_callback_func)[0] == '\0'))
  + {
  + zend_throw_exception_ex(NULL, 0, "can not find class %s", class_name->val TSRMLS_CC);
  + return NULL;
  + }
  +
  zend_string *fname = swoole_string_init(PG(unserialize_callback_func), strlen(PG(unserialize_callback_func)));
  Z_STR(user_func) = fname;
  Z_TYPE_INFO(user_func) = IS_STRING_EX;
  @@ -1274,7 +1282,7 @@ static void* swoole_unserialize_object(void *buffer, zval *return_value, zend_uc
  zend_string *class_name;
  if (flag == UNSERIALIZE_OBJECT_TO_STDCLASS)
  {
  - class_name = swoole_string_init("StdClass", 8);
  + class_name = swoole_string_init("StdClass", 9);
  }
  else
  {
  