extmod/vfs: Fix lookup of entry in root dir so it fails correctly.

Prior to this commit, uos.chdir('/') followed by uos.stat('noexist') would
succeed that stat even though the entry did not exist (some other functions
like listdir would have similar issues).  This is because, if the current
directory was the root and the path was relative, mp_vfs_lookup_path would
return success for bad paths.

Signed-off-by: Damien George <damien@micropython.org>
This commit is contained in:
Damien George 2020-09-22 15:05:00 +10:00
parent 3e16763201
commit 71adf506ce
3 changed files with 22 additions and 6 deletions

View File

@ -83,12 +83,8 @@ mp_vfs_mount_t *mp_vfs_lookup_path(const char *path, const char **path_out) {
}
}
// if we get here then there's nothing mounted on /
if (is_abs) {
// path began with / and was not found
return MP_VFS_NONE;
}
// if we get here then there's nothing mounted on /, so the path doesn't exist
return MP_VFS_NONE;
}
// a relative path within a mounted device

View File

@ -74,6 +74,14 @@ print(uos.statvfs("/")[9] >= 32)
# getcwd when in root dir
print(uos.getcwd())
# test operations on the root directory with nothing mounted, they should all fail
for func in ("chdir", "listdir", "mkdir", "remove", "rmdir", "stat"):
for arg in ("x", "/x"):
try:
getattr(uos, func)(arg)
except OSError:
print(func, arg, "OSError")
# basic mounting and listdir
uos.mount(Filesystem(1), "/test_mnt")
print(uos.listdir())

View File

@ -1,6 +1,18 @@
(16384, 0, 0, 0, 0, 0, 0, 0, 0, 0)
True
/
chdir x OSError
chdir /x OSError
listdir x OSError
listdir /x OSError
mkdir x OSError
mkdir /x OSError
remove x OSError
remove /x OSError
rmdir x OSError
rmdir /x OSError
stat x OSError
stat /x OSError
1 mount False False
['test_mnt']
('test_mnt', 16384, 0)