extmod/vfs_fat: Add fat_vfs_statvfs(), reused from stmhal.

extmod/vfs_fat.c

@@ -250,6 +250,36 @@ STATIC mp_obj_t fat_vfs_stat(mp_obj_t vfs_in, mp_obj_t path_in) {
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_2(fat_vfs_stat_obj, fat_vfs_stat);
 
+// Get the status of a VFS.
+STATIC mp_obj_t fat_vfs_statvfs(mp_obj_t vfs_in, mp_obj_t path_in) {
+    (void)vfs_in;
+    const char *path = mp_obj_str_get_str(path_in);
+
+    FATFS *fatfs;
+    DWORD nclst;
+    FRESULT res = f_getfree(path, &nclst, &fatfs);
+    if (FR_OK != res) {
+        nlr_raise(mp_obj_new_exception_arg1(&mp_type_OSError,
+          MP_OBJ_NEW_SMALL_INT(fresult_to_errno_table[res])));
+    }
+
+    mp_obj_tuple_t *t = MP_OBJ_TO_PTR(mp_obj_new_tuple(10, NULL));
+
+    t->items[0] = MP_OBJ_NEW_SMALL_INT(fatfs->csize * fatfs->ssize); // f_bsize
+    t->items[1] = t->items[0]; // f_frsize
+    t->items[2] = MP_OBJ_NEW_SMALL_INT((fatfs->n_fatent - 2) * fatfs->csize); // f_blocks
+    t->items[3] = MP_OBJ_NEW_SMALL_INT(nclst); // f_bfree
+    t->items[4] = t->items[3]; // f_bavail
+    t->items[5] = MP_OBJ_NEW_SMALL_INT(0); // f_files
+    t->items[6] = MP_OBJ_NEW_SMALL_INT(0); // f_ffree
+    t->items[7] = MP_OBJ_NEW_SMALL_INT(0); // f_favail
+    t->items[8] = MP_OBJ_NEW_SMALL_INT(0); // f_flags
+    t->items[9] = MP_OBJ_NEW_SMALL_INT(_MAX_LFN); // f_namemax
+
+    return MP_OBJ_FROM_PTR(t);
+}
+STATIC MP_DEFINE_CONST_FUN_OBJ_2(fat_vfs_statvfs_obj, fat_vfs_statvfs);
+
 // Unmount the filesystem
 STATIC mp_obj_t fat_vfs_umount(mp_obj_t vfs_in) {
     fatfs_umount(((fs_user_mount_t *)vfs_in)->readblocks[1]);
@@ -268,6 +298,7 @@ STATIC const mp_rom_map_elem_t fat_vfs_locals_dict_table[] = {
     { MP_ROM_QSTR(MP_QSTR_remove), MP_ROM_PTR(&fat_vfs_remove_obj) },
     { MP_ROM_QSTR(MP_QSTR_rename), MP_ROM_PTR(&fat_vfs_rename_obj) },
     { MP_ROM_QSTR(MP_QSTR_stat), MP_ROM_PTR(&fat_vfs_stat_obj) },
+    { MP_ROM_QSTR(MP_QSTR_statvfs), MP_ROM_PTR(&fat_vfs_statvfs_obj) },
     { MP_ROM_QSTR(MP_QSTR_umount), MP_ROM_PTR(&fat_vfs_umount_obj) },
 };
 STATIC MP_DEFINE_CONST_DICT(fat_vfs_locals_dict, fat_vfs_locals_dict_table);