Re: [Libguestfs] [PATCH v3 8/8] lib/canonical-name.c: Hide EINVAL error from underlying API call.

On Fri, Oct 09, 2020 at 11:33:43AM +0100, Richard W.M. Jones wrote: > > This is the patch I tested which works (on top of the > patch posted): > > diff --git a/lib/canonical-name.c b/lib/canonical-name.c > index e0c7918b4..ae4def692 100644 > --- a/lib/canonical-name.c > +++ b/lib/canonical-name.c > @@ -53,8 +53,16 @@ guestfs_impl_canonical_device_name (guestfs_h *g, const char *device) > * BitLocker-encrypted volume, so simply return the original > * name in that case. > */ > - if (ret == NULL && guestfs_last_errno (g) == EINVAL) > - ret = safe_strdup (g, device); > + if (ret == NULL) { > + if (guestfs_last_errno (g) == EINVAL) > + ret = safe_strdup (g, device); > + else > + /* Make sure the original error gets pushed through the > + * error handlers. > + */ > + guestfs_int_error_errno (g, guestfs_last_errno (g), > + "%s", guestfs_last_error (g)); > + } > } > else > ret = safe_strdup (g, device); > > --- > > Current upstream: > > $ guestfish scratch 1M : run : canonical-device-name "/dev/dm-999" > libguestfs: error: lvm_canonical_lv_name: stat: /dev/dm-999: No such file or directory > /dev/dm-999 <----- > > Patch posted without the above patch added: > > $ ./run guestfish scratch 1M : run : canonical-device-name "/dev/dm-999" > > (no output, but the command fails with exit code 1) > > Patch posted + above patch: > > $ ./run guestfish scratch 1M : run : canonical-device-name "/dev/dm-999" > libguestfs: error: lvm_canonical_lv_name: stat: /dev/dm-999: No such file or directory Actually I didn't notice this, but it improves on the current upstream behaviour. Current upstream calls the error handlers and returns a non-error original string (see <----- line above) and exit code 0. With the patch we return an error.