+
+void _tbm_set_last_result(tbm_error_e err);
+
+char *_tbm_flag_to_str(int f);
+
+/* functions for mutex */
+void _tbm_bufmgr_mutex_lock(void);
+void _tbm_bufmgr_mutex_unlock(void);
+tbm_bo tbm_bufmgr_internal_find_bo(tbm_bufmgr bufmgr, tbm_bo bo);
+
+tbm_bo tbm_bufmgr_internal_alloc_bo(tbm_bufmgr bufmgr, int size, int flags);
+tbm_bo tbm_bufmgr_internal_alloc_bo_with_format(tbm_bufmgr bufmgr, int format, int bo_idx, int width, int bpp, int height, tbm_bo_memory_type flags, tbm_error_e *error);
+tbm_bo tbm_bufmgr_internal_alloc_bo_with_bo_data(tbm_bufmgr bufmgr, tbm_bo_data *bo_data, int flags, tbm_error_e *error);
+tbm_bo tbm_bufmgr_internal_import_bo_with_key(tbm_bufmgr bufmgr, tbm_key key);
+tbm_bo tbm_bufmgr_internal_import_bo_with_fd(tbm_bufmgr bufmgr, tbm_fd fd);
+
+#endif /* _TBM_BUFMGR_INT_H_ */