Implement fixed buffer vstrs; use them for import path.
diff --git a/py/mpconfig.h b/py/mpconfig.h
index 38b74b7..799c9d8 100644
--- a/py/mpconfig.h
+++ b/py/mpconfig.h
@@ -101,6 +101,12 @@
#define MICROPY_CPYTHON_COMPAT (1)
#endif
+// Maximum length of a path in the filesystem
+// So we can allocate a buffer on the stack for path manipulation in import
+#ifndef MICROPY_PATH_MAX
+#define MICROPY_PATH_MAX (512)
+#endif
+
/*****************************************************************************/
/* Miscellaneous settings */