GNU Hurd/ open issues/ glibc ioctls

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IRC, unknown channel, unknown date

<pinotree> d'oh, broken defines for ioctl()!
<pinotree> http://paste.debian.net/45021/ ← any idea about this? looks like something fishy with the SIO* defines
<pinotree> tschwinge: ↑ know anything about this?
<pinotree> #define _IOT_arpreq       _IOT_SIMPLE (struct arpreq) ← looks like it is missing for bits/ioctls.h
<pinotree> eglibc patch submitted-ioctl-unsigned-size_t.diff should be pimped a bit

<pinotree> youpi: while trying to compile ossp-uuid (needed by pgsql 8.4, needed by various other stuff), i found a bug in a hurd libc header
<youpi> that's possible
<pinotree> it has a ioctrl() using an id with a value having type 'struct arpreq'
<youpi> ah, that's not a bug then
<youpi> see the ioctl section of the porting page of the wiki
<pinotree> due to the sort of "mangling" done in bits/ioctrls.h, there should be an helper macro for the size of the struct arpreq
<pinotree> +#define _IOT_arpreq       _IOT_SIMPLE (struct arpreq)  ← adding this before any header was enough
* pinotree looks
<youpi> it's not to be done so simply
<youpi> see the page :)
<youpi> I'm afraid _IOT_arpreq can't be properly defined
* pinotree is not finding it...
<pinotree> the closest i see is http://lists.gnu.org/archive/html/bug-hurd/2006-03/msg00025.html
<youpi> that's it yes
<youpi> I mean, that's the kind of thing
<youpi> but not the wiki page, let me look
<youpi> http://www.gnu.org/software/hurd/hurd/porting/guidelines.html
<pinotree> i also saw a glib patch adding few types like that (char, short, int)
<youpi> yes that's the same kind of thing
<pinotree> i see
<youpi> setting it to _IOT_SIMPLE(struct arpreq) would probably work with 32bit gnumach and 32bit userland, but may not with e.g. 64bit gnumach and 32bit userland and such
<pinotree> hmmm, sockaddr,sockaddr,int,sockaddr,char[16]
<pinotree> so basically it would support at most 3 elements in a passed struct?
<pinotree> s/elements/fields/
<youpi> 3 kinds of fields
<youpi> as you provide a count
<pinotree> youpi: so basically: #define _IOT_arpreq _IOT (_IOTS (struct sockaddr), 3, _IOTS (int), 1, _IOTS (char), 16) ?
<pinotree> ie the order of the fields in the struct does not matter, it seems?
<youpi> the order of the fields does matter
<youpi> as this encodes how mig will read the struct to send them
<pinotree> uhm
<youpi> also, _IOTS(struct sockaddr) won't work
<pinotree> yeah i should define it too
<youpi> no, it even needs to be replaced by its content
<pinotree> ah
<pinotree> it is possible to compose the _IOTS()?
<pinotree> (to build structs with more than 3 kind of fields)
<youpi> no
<pinotree> d'oh
<youpi> that's a hard shortcoming of the whole ioctl encoding
* pinotree scratches his head
<youpi> there's no way but redefining ioctl(), really
<youpi> it was a funny trick to encode it this way, but unrealistic
<pinotree> i see, yes
<youpi> not to mention ioctls which contain pointers, which just can not be passed to mig
<pinotree> indeed
<youpi> actually it's not mach's ioctl issue
<youpi> as mach doesn't know ioctl
<youpi> but the hurd ioctl interface
<pinotree> right
<youpi> which might end up in mach, other processes, other machines, etc.
* pinotree s/Mach/Hurd/ :)

TIOCCONS

IRC, freenode, #hurd, 2014-02-05

<gnu_srs> Hi, anybody have time to look at what fails with: ioctl(0,
  TIOCCONS, NULL)?
<gnu_srs> found a program doing the same function call as bootlogd:
  http://paste.debian.net/80231/
<gnu_srs> rpctrace: http://paste.debian.net/80232/
<youpi> gnu_srs: it seems there  is a misunderstanding between linux and
  *bsd on this one
<youpi> to be able to work on *bsd (and on hurd too), the source code
  should replace its NULL parameter with the address of an integer
  containing 1
<youpi> see
  http://lists.freebsd.org/pipermail/freebsd-current/2011-January/022116.html
  for the bsd implementation, for instance
<gnu_srs> youpi: replacing 0 with &i where int i=1 gives: TIOCCONS:
  Inappropriate ioctl for device
<youpi> so be it, but that's clearly needed to be able to work on bsd
<youpi> and probably the implementation is just missing on the Hurd for now
<gnu_srs> jus to be clear: do you mean 0 or NULL in: ioctl(0, TIOCCONS,
  NULL)?
<youpi> yes, for instance there is an implementation do_tiocsctty in glibc,
  but no to_tioccons
<youpi> I mean NULL
<gnu_srs> OK, that's where I changed, the first argument id the FD
<youpi> well, when I wrote "NULL", I really meant "NULL" ...
<gnu_srs> yes sure, so you say that it is not yet implemented?
<youpi> yes, for instance there is an implementation do_tiocsctty in glibc,
  but no to_tioccons
<gnu_srs> easy to do?
<youpi> no idea, I don't even know what that is suppsoed to do
<youpi> it's probably something like tiocsctty, but I don't really know
<gnu_srs> Redirecting console output to a pseudotty
<youpi> omg that ioctl is so ugly
<youpi> the way I can see it working is to add an RPC to the /dev/console
  translator (i.e. /hurd/term) to give it the fd, and have /hurd/term write
  to it whenever it gets writes, instead of writing to the console device
<youpi> gnu_srs: what do you need that for?
<gnu_srs> bootlogd in sysvinit use that for logging.
<gnu_srs> should I propose a patch to avoid the segfault when booting then?
<youpi> at least, yes
<youpi> *bsd will need it anyway
<gnu_srs> youpi: btw: hurd console does not work when running openrc,
  neither is halt/reboot. Maybe you should try it out?
<gnu_srs> bootlogd use  ioctl(0, TIOCCONS, NULL) a Linux (only) construct
<gnu_srs> ?
<youpi> gnu_srs: I had infinite time in the day, I would be able to try it
  out, yes
<braunr> heh
<youpi> giving NULL to TIOCCONS is a linux-only construct, yes
<youpi> to be compatible with *BSD, you have to pass the parameter
  mentioned above
<youpi> instead of NULL
<gnu_srs> well bootlogd is from sysvinit, so it is a matter if we move to
  that for init.
<gnu_srs> ***checking if bootlogd segfaults on kFreeBSD too

Non-constant structures as IOCTL parameter

Debian bug #413734.

IRC, OFTC, #debian-hurd, 2014-02-16

<gg0> https://bugs.debian.org/413734
<gg0> patch #2 has become http://paste.debian.net/plain/82412/
<gg0> ie. almost entirely ifdef'ing DeviceEnum
<gg0> ok final patch is http://paste.debian.net/plain/82440/
<gg0> could anyone review it, especially last 3 oss hunks?
<azeem> gg0: well probably it would be cleaner to have autoconf check for
  any of the three soundcard.h include locations?
<gg0> azeem: i think if upstream is ok with 2 it could be ok with 3 too
<gg0> my concern is about linux/ in header path (hurd is not linux) and
  about ways cleaner than last 2 hunks
<azeem> well yeah, #ifdef __GNU__ #include <linux/foo.h> certainly looks
  ugly
<gg0> i'll ifdef ioctls only

IRC, OFTC, #debian-hurd, 2014-02-17

<gg0> http://paste.debian.net/plain/82446/
<gg0> https://trac.videolan.org/vlc/ticket/10696

IRC, freenode, #hurd, 2014-02-17

<gg0> porting vlc with http://paste.debian.net/plain/82446/ +
  http://paste.debian.net/plain/82510/
<gg0> what's the proper way to fix ioctl instead of ifdef'ing them?
<gg0> see https://bugs.debian.org/413734
<braunr> gg0: defining them in libc
<braunr> and in servers implementing them ofc