py/builtin: Clean up and simplify import_stat and builtin_open config.

The following changes are made:

- If MICROPY_VFS is enabled then mp_vfs_import_stat and mp_vfs_open are
  automatically used for mp_import_stat and mp_builtin_open respectively.

- If MICROPY_PY_IO is enabled then "open" is automatically included in the
  set of builtins, and points to mp_builtin_open_obj.

This helps to clean up and simplify the most common port configuration.

Signed-off-by: Damien George <damien@micropython.org>

1 files changed, 36 insertions, 3 deletions

diff --git a/py/builtin.h b/py/builtin.h
index 162fed77cc..a6f824ca20 100644
--- a/py/builtin.h
+++ b/py/builtin.h
@@ -28,8 +28,43 @@
 
 #include "py/obj.h"
 
-mp_obj_t mp_builtin___import__(size_t n_args, const mp_obj_t *args);
+typedef enum {
+    MP_IMPORT_STAT_NO_EXIST,
+    MP_IMPORT_STAT_DIR,
+    MP_IMPORT_STAT_FILE,
+} mp_import_stat_t;
+
+#if MICROPY_VFS
+
+// Delegate to the VFS for import stat and builtin open.
+
+#define mp_builtin_open_obj mp_vfs_open_obj
+
+mp_import_stat_t mp_vfs_import_stat(const char *path);
+mp_obj_t mp_vfs_open(size_t n_args, const mp_obj_t *args, mp_map_t *kwargs);
+
+MP_DECLARE_CONST_FUN_OBJ_KW(mp_vfs_open_obj);
+
+static inline mp_import_stat_t mp_import_stat(const char *path) {
+    return mp_vfs_import_stat(path);
+}
+
+static inline mp_obj_t mp_builtin_open(size_t n_args, const mp_obj_t *args, mp_map_t *kwargs) {
+    return mp_vfs_open(n_args, args, kwargs);
+}
+
+#else
+
+// A port can provide implementations of these functions.
+mp_import_stat_t mp_import_stat(const char *path);
 mp_obj_t mp_builtin_open(size_t n_args, const mp_obj_t *args, mp_map_t *kwargs);
+
+// A port can provide this object.
+MP_DECLARE_CONST_FUN_OBJ_KW(mp_builtin_open_obj);
+
+#endif
+
+mp_obj_t mp_builtin___import__(size_t n_args, const mp_obj_t *args);
 mp_obj_t mp_micropython_mem_info(size_t n_args, const mp_obj_t *args);
 
 MP_DECLARE_CONST_FUN_OBJ_VAR(mp_builtin___build_class___obj);
@@ -76,9 +111,7 @@ MP_DECLARE_CONST_FUN_OBJ_1(mp_builtin_repr_obj);
 MP_DECLARE_CONST_FUN_OBJ_VAR_BETWEEN(mp_builtin_round_obj);
 MP_DECLARE_CONST_FUN_OBJ_KW(mp_builtin_sorted_obj);
 MP_DECLARE_CONST_FUN_OBJ_VAR_BETWEEN(mp_builtin_sum_obj);
-// Defined by a port, but declared here for simplicity
 MP_DECLARE_CONST_FUN_OBJ_VAR_BETWEEN(mp_builtin_input_obj);
-MP_DECLARE_CONST_FUN_OBJ_KW(mp_builtin_open_obj);
 
 MP_DECLARE_CONST_FUN_OBJ_2(mp_namedtuple_obj);