----- Am 27. Feb 2018 um 13:11 schrieb Jakob Viketoft jakob.viket...@aacmicrotec.com:
> From: Joel Sherrill [j...@rtems.org] > Sent: Monday, February 26, 2018 14:36 >>> On Feb 26, 2018 8:27 AM, "Jakob Viketoft" <jakob.viket...@aacmicrotec.com> >>> wrote: > >>> Hello Joel, > >>> From: Joel Sherrill [j...@rtems.org] >>> Sent: Monday, February 26, 2018 12:21 > >>>> On Feb 26, 2018 5:13 AM, "Jakob Viketoft" <jakob.viket...@aacmicrotec.com> >>>> wrote: >>>>> E.g. could it be possible for the translation mechanism to look if there >>>>> is >>>>> already an errno defined and then return this instead of doing the error >>>>> code >>>>> translation? > >>>>> It seems like the translation I'm talking about happens in the >>>>> rtems_deviceio_write() function in >>>>> cpukit/libcsupport/src/sup_fs_deviceio.c > >>>> Completely random thought as I sit on a plane without code. > >>>> Add a field to the arguments structure for errno. See it to zero before the >>>> call. If it is set to non-zero after the call, then the driver wanted to >>>> return >>>> errno directly. Otherwise translate. > >>> This was my thought as well, I just wanted to bounce it off the RTEMS list >>> and >>> also possibly get official support for a feature as this. > >> Now boarded on a different plane and have had another round of thinking. > >> What if an RTEMS status code were added like RTEMS_STATUS_IN_ERRNO and we >> don't >> modify the arguments structure. Then a driver could return that status to >> trip >> -1 and errno. > > Yes, that would work just as well for us and is even less work / impact. > >> Just a thought. I think it would make the code cleaner but another core >> developer should pipe up. I was up at 3am to catch a flight and could be >> loopy. >> :) > > Anyone else? :) I think you try to improve the wrong driver framework. This classic device support is a legacy API. It is inflexible and has a considerable overhead due to an excessive layering and the use of minor numbers. A driver registered via IMFS_make_generic_node() already provides the functionality you are asking. _______________________________________________ devel mailing list devel@rtems.org http://lists.rtems.org/mailman/listinfo/devel
