Missing definitions for UTMP(x)

Missing definitions for UTMP(x)

[Matias Fonzo]

Hi there,

We were building mesa (17.2.0-rc4) for Dragora, and we get this errors:

In file included from sessreg.c:73:0:
sessreg.c: In function 'main':
sessreg.h:107:21: error: '_PATH_WTMPX' undeclared (first use in this
function) # define WTMPX_FILE _PATH_WTMPX
                     ^
sessreg.c:302:16: note: in expansion of macro 'WTMPX_FILE'
   wtmpx_file = WTMPX_FILE;
                ^~~~~~~~~~
sessreg.h:107:21: note: each undeclared identifier is reported only
once for each function it appears in # define WTMPX_FILE _PATH_WTMPX
                     ^
sessreg.c:302:16: note: in expansion of macro 'WTMPX_FILE'
   wtmpx_file = WTMPX_FILE;
                ^~~~~~~~~~
sessreg.h:110:21: error: '_PATH_UTMPX' undeclared (first use in this
function) # define UTMPX_FILE _PATH_UTMPX
                     ^
sessreg.c:308:16: note: in expansion of macro 'UTMPX_FILE'
   utmpx_file = UTMPX_FILE;
                ^~~~~~~~~~
make[2]: *** [Makefile:489: sessreg.o] Error 1
make[1]: *** [Makefile:509: all-recursive] Error 1
make: *** [Makefile:381: all] Error 2

Glibc defines in utmpx.h:

#ifdef __USE_GNU
/* Compatibility names for the strings of the canonical file names.  */
# define UTMPX_FILE     _PATH_UTMPX
# define UTMPX_FILENAME _PATH_UTMPX
# define WTMPX_FILE     _PATH_WTMPX
# define WTMPX_FILENAME _PATH_WTMPX
#endif

Please, include it.

Re: Missing definitions for UTMP(x)

[A. Wilcox]

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Hash: SHA256

On 28/08/17 16:57, Matias Fonzo wrote:
> sessreg.h:110:21: error: '_PATH_UTMPX' undeclared (first use in
> this function) # define UTMPX_FILE _PATH_UTMPX ^ sessreg.c:308:16:
> note: in expansion of macro 'UTMPX_FILE' utmpx_file = UTMPX_FILE; 
> ^~~~~~~~~~


> # define UTMPX_FILE     _PATH_UTMPX


> Please, include it.


If you'll notice, this would cause preprocessor recursion.

The musl libc does not actually support utmpx or wtmpx.  For better
support you need to add another library such as libutx:

https://code.foxkit.us/adelie/libutx

This library is not yet fully functional, as it does not yet provide
wtmp(x).  It does however fully implement utmp(x).  It may give clues
as to what you'll need to do to make this functional on musl libc.

What we do in Adélie is actually put these two files in the musl
codebase itself as a patch, so that all programs can have it
available.  An eventual goal is to make it a separate library, and
have programs that can use utmpx features attempt to dlopen the
library.  If the library exists on the system, they use it; if the
library does not exist on the system, the user has chosen to disable
it and that part of the software is disabled.

Unfortunately that is going to require a massive effort and the
cooperation of many disparate upstreams.  I don't hold my breath for
such a time.  Until then, having it always available with a simple
solution for those who do not want it (symlink /var/run/utmp ->
/dev/null) is what we are using.


Best,
- --arw


- -- 
A. Wilcox (awilfox)
Project Lead, Adélie Linux
http://adelielinux.org
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Re: Missing definitions for UTMP(x)

[Matias Fonzo]

Hi A. Wilcox,

On Mon, 28 Aug 2017 21:09:00 -0500
"A. Wilcox" <awilfox@adelielinux.org> wrote:
> 
> If you'll notice, this would cause preprocessor recursion.
> 
> The musl libc does not actually support utmpx or wtmpx.  For better
> support you need to add another library such as libutx:
> 
> https://code.foxkit.us/adelie/libutx
> 

Thanks for the information.  :-)

> [..]

Regards,
Matías

Re: Missing definitions for UTMP(x)

[u-uy74]

On Mon, Aug 28, 2017 at 06:57:27PM -0300, Matias Fonzo wrote:
> We were building mesa (17.2.0-rc4) for Dragora, and we get this errors:
> 
> In file included from sessreg.c:73:0:
> sessreg.c: In function 'main':
> sessreg.h:107:21: error: '_PATH_WTMPX' undeclared (first use in this

$ tar tvzf mesa-17.2.0-rc4.tar.gz | grep sessreg || echo MISSING
MISSING
$

The problem is somewhere else than in mesa :)

A sufficient fix (while building sessreg as a part of xorg-apps)
was for me

 sed -i '/^#define HAVE_UPDWTMPX 1/d' config.h

Depending on the sessreg version and the building options
something else might be needed or not, but not much.

Regards,
Rune

Re: Missing definitions for UTMP(x)

[Matias Fonzo]

On Tue, 29 Aug 2017 13:05:56 +0200
u-uy74@aetey.se wrote:

> On Mon, Aug 28, 2017 at 06:57:27PM -0300, Matias Fonzo wrote:
> > We were building mesa (17.2.0-rc4) for Dragora, and we get this
> > errors:
> > 
> > In file included from sessreg.c:73:0:
> > sessreg.c: In function 'main':
> > sessreg.h:107:21: error: '_PATH_WTMPX' undeclared (first use in
> > this  
> 
> $ tar tvzf mesa-17.2.0-rc4.tar.gz | grep sessreg || echo MISSING
> MISSING
> $
> 
> The problem is somewhere else than in mesa :)

Sorry, it was about the definition but not in mesa -> sessreg.
 
> A sufficient fix (while building sessreg as a part of xorg-apps)
> was for me
> 
>  sed -i '/^#define HAVE_UPDWTMPX 1/d' config.h

I will tell to the packager to try this.
 
> Depending on the sessreg version and the building options
> something else might be needed or not, but not much.
> 

Thanks.