On (05/10/15 09:35), Jakub Hrozek wrote:
On Tue, Sep 08, 2015 at 04:11:26PM +0200, Michal Židek wrote:
> On 09/08/2015 03:31 PM, Lukas Slebodnik wrote:
> >On (08/09/15 15:21), Michal Židek wrote:
> >>On 09/08/2015 03:09 PM, Lukas Slebodnik wrote:
> >>>On (08/09/15 14:57), Michal Židek wrote:
> >>>>On 08/27/2015 12:52 PM, Lukas Slebodnik wrote:
> >>>>>On (19/08/15 15:57), Michal Židek wrote:
> >>>>>>On 08/12/2015 01:11 PM, Lukas Slebodnik wrote:
> >>>>>>>ehlo,
> >>>>>>>
> >>>>>>>attached patch shoul avoid situation as in commit
7c69221077c780e62f6c536e78675f2dc1c131bc
> >>>>>>>The comments does not guarantee anything.
> >>>>>>>
> >>>>>>>Author: Michal Zidek <mzidek(a)redhat.com>
> >>>>>>>Date: Tue Mar 10 17:30:48 2015 +0100
> >>>>>>>
> >>>>>>> DEBUG: Add missing strings for error messages
> >>>>>>>
> >>>>>>> We had more error codes than corresponding
> >>>>>>> messages. Also order of two messages was wrong.
> >>>>>>>
> >>>>>>>Unfortunatelly, the index of enum do not start from 0
> >>>>>>>and need to be converted using SSSD_ERR_IDX. I used
shorter version of
> >>>>>>>macro "idx". Feel free to propose nicer name.
> >>>>>>
> >>>>>>I would use the SSSD_ERR_IDX and not create an alias for it.
> >>>>>>I think it is always better to have properly namespaced
macros
> >>>>>>even if the are a little longer.
> >>>>>>
> >>>>>a) the macro is not in public header.
> >>>>
> >>>>It is int util_errors.h
> >>>>
> >>>>git grep '#include .*util_errors.h'
> >>>>src/providers/dp_refresh.c:#include "util/util_errors.h"
> >>>>src/providers/ipa/ipa_dyndns.h:#include
"util/util_errors.h"
> >>>>src/providers/krb5/krb5_child.c:#include
"src/util/util_errors.h"
> >>>>src/tests/sbus_codegen_tests.c:#include
"util/util_errors.h"
> >>>>src/tests/sbus_tests.c:#include "util/util_errors.h"
> >>>>src/util/util.h:#include "util/util_errors.h"
> >>>> ^^^^^^^^
> >>>>So it is almost everywhere with the exception of the
> >>>>client code.
> >>>>
> >>>I meant that the local version of SSSD_ERR_IDX is not im public
> >>>header. So it could not colide with other files.
>
> Ah, yes sorry, I misunderstood your text.
>
> >>>
> >>>>>b) SSSD_ERR_IDX significantly decrease readability
> >>>>
> >>>>Not properly namespacing macros can bite us in the
> >>>>long term. I do not think that SSSD_ERR_IDX decreases
> >>>>readability, but even if it was the case I would say
> >>>>it is simply necessary. Both SSSD_ and ERR_ prefixes are
> >>>>important here.
> >>>>
> >>>
> >>>OK,
> >>>try to compare few followinf versions and choose the one which
> >>>can be easily proceed/understood.
> >>>
> >>>a)
> >>>struct err_string error_to_str[ SSSD_ERR_IDX(ERR_LAST) + 1 ] = {
> >>> [SSSD_ERR_IDX(ERR_INVALID) ] = { "Invalid Error" },
> >>> [SSSD_ERR_IDX(ERR_INTERNAL) ] = { "Internal Error" },
> >>> [SSSD_ERR_IDX(ERR_ACCOUNT_UNKNOWN) ] = { "Account Unknown"
},
> >>> [SSSD_ERR_IDX(ERR_INVALID_CRED_TYPE) ] = { "Invalid credential
type" },
> >>> [SSSD_ERR_IDX(ERR_NO_CREDS) ] = { "No credentials
available" },
> >>> [SSSD_ERR_IDX(ERR_CREDS_EXPIRED) ] = { "Credentials are
expired" },
> >>>
> >>>
> >>>b)
> >>>struct err_string error_to_str[ idx(ERR_LAST) + 1 ] = {
> >>> [ idx(ERR_INVALID) ] = { "Invalid Error" },
> >>> [ idx(ERR_INTERNAL) ] = { "Internal Error" },
> >>> [ idx(ERR_ACCOUNT_UNKNOWN) ] = { "Account Unknown" },
> >>> [ idx(ERR_INVALID_CRED_TYPE) ] = { "Invalid credential
type" },
> >>> [ idx(ERR_NO_CREDS) ] = { "No credentials available" },
> >>> [ idx(ERR_CREDS_EXPIRED) ] = { "Credentials are expired"
},
> >>>
> >>>
> >>>c)
> >>>struct err_string error_to_str[ _(ERR_LAST) + 1 ] = {
> >>> [ _(ERR_INVALID) ] = { "Invalid Error" },
> >>> [ _(ERR_INTERNAL) ] = { "Internal Error" },
> >>> [ _(ERR_ACCOUNT_UNKNOWN) ] = { "Account Unknown" },
> >>> [ _(ERR_INVALID_CRED_TYPE) ] = { "Invalid credential type"
},
> >>> [ _(ERR_NO_CREDS) ] = { "No credentials available" },
> >>> [ _(ERR_CREDS_EXPIRED) ] = { "Credentials are expired" },
> >>>
> >>>
> >>>d)
> >>>struct err_string error_to_str[] = {
> >>> { "Invalid Error" }, /* ERR_INVALID */
> >>> { "Internal Error" }, /* ERR_INTERNAL */
> >>> { "Account Unknown" }, /* ERR_ACCOUNT_UNKNOWN */
> >>> { "Invalid credential type" }, /* ERR_INVALID_CRED_TYPE
*/
> >>> { "No credentials available" }, /* ERR_NO_CREDS */
> >>> { "Credentials are expired" }, /* ERR_CREDS_EXPIRED */
> >>>
> >>>
> >>>IMHO, the last one is the best, but there is not a compile time check.
> >>>
> >>>LS
> >>
> >>I would choose a). It may be less readable than d) but has
> >>compile time checks. Both b) and c) are not properly namespaced.
> >>
> >I would rather used option d) than option a). (Do not change anything)
> >
> >Option b) does not require namespacing, because it is a local macro.
>
> Well, I still think that it is better to namespace macros even if they
> are local. Unlike functions, there are ways to propagate macros
> by other means than header files so the collision may happen
> in some cases. But yes that would require someone to use
> not namespaced macro on place where it would be obviously
> dangerous (like in Makefile) so we would catch it. This makes
> option b) acceptable.
>
> Please rebase the patches and if you do not decide to go
> with option a) (which I would prefer) I can accept the
> option b) as well.
>
> >Option c) is the most readable, but there is a collision with gnu gettext.
>
> Option c) is not readable because it makes people think "What
> is gettext macro doing here?". The confusion is even bigger because
> we use human readable text nearby.
This thread has stalled, let's try to revive it. It would be nice to
merge the patch.
tl;dr I mostly agree with Michal and would prefer namespaced macro, even
though it's a local one.
The main problem is a readability of code with such macro.
It's hard to find name of error code there.
struct err_string error_to_str[ SSSD_ERR_IDX(ERR_LAST) + 1 ] = {
[ SSSD_ERR_IDX(ERR_INVALID) ] = { "Invalid Error" },
[ SSSD_ERR_IDX(ERR_INTERNAL) ] = { "Internal Error" },
[ SSSD_ERR_IDX(ERR_ACCOUNT_UNKNOWN) ] = { "Account Unknown" },
[ SSSD_ERR_IDX(ERR_INVALID_CRED_TYPE) ] = { "Invalid credential type" },
[ SSSD_ERR_IDX(ERR_NO_CREDS) ] = { "No credentials available" },
[ SSSD_ERR_IDX(ERR_CREDS_EXPIRED) ] = { "Credentials are expired" },
Try to propose something else.
The ideal would be something short (or lowecased) as with "_".
struct err_string error_to_str[ _(ERR_LAST) + 1 ] = {
[ _(ERR_INVALID) ] = { "Invalid Error" },
[ _(ERR_INTERNAL) ] = { "Internal Error" },
[ _(ERR_ACCOUNT_UNKNOWN) ] = { "Account Unknown" },
[ _(ERR_INVALID_CRED_TYPE) ] = { "Invalid credential type" },
[ _(ERR_NO_CREDS) ] = { "No credentials available" },
[ _(ERR_CREDS_EXPIRED) ] = { "Credentials are expired" },
LS