extmod/vfs: Allow to statvfs the root directory.

1 files changed, 26 insertions, 0 deletions

diff --git a/extmod/vfs.c b/extmod/vfs.c
index f158bd387..b75ec7516 100644
--- a/extmod/vfs.c
+++ b/extmod/vfs.c
@@ -421,6 +421,32 @@ MP_DEFINE_CONST_FUN_OBJ_1(mp_vfs_stat_obj, mp_vfs_stat);
 mp_obj_t mp_vfs_statvfs(mp_obj_t path_in) {
     mp_obj_t path_out;
     mp_vfs_mount_t *vfs = lookup_path(path_in, &path_out);
+    if (vfs == MP_VFS_ROOT) {
+        // statvfs called on the root directory, see if there's anything mounted there
+        for (vfs = MP_STATE_VM(vfs_mount_table); vfs != NULL; vfs = vfs->next) {
+            if (vfs->len == 1) {
+                break;
+            }
+        }
+
+        // If there's nothing mounted at root then return a mostly-empty tuple
+        if (vfs == NULL) {
+            mp_obj_tuple_t *t = MP_OBJ_TO_PTR(mp_obj_new_tuple(10, NULL));
+
+            // fill in: bsize, frsize, blocks, bfree, bavail, files, ffree, favail, flags
+            for (int i = 0; i <= 8; ++i) {
+                t->items[i] = MP_OBJ_NEW_SMALL_INT(0);
+            }
+
+            // Put something sensible in f_namemax
+            t->items[9] = MP_OBJ_NEW_SMALL_INT(MICROPY_ALLOC_PATH_MAX);
+
+            return MP_OBJ_FROM_PTR(t);
+        }
+
+        // VFS mounted at root so delegate the call to it
+        path_out = MP_OBJ_NEW_QSTR(MP_QSTR__slash_);
+    }
     return mp_vfs_proxy_call(vfs, MP_QSTR_statvfs, 1, &path_out);
 }
 MP_DEFINE_CONST_FUN_OBJ_1(mp_vfs_statvfs_obj, mp_vfs_statvfs);