RFC: change to /usr/lib/rpm/mono-find-provides

[Christian Krause]

Hi,

First let me introduce me shortly: My Name is Christian and I've started
some months ago to be a Fedora Package maintainer. Especially I'm
interested in some of the mono packages, so that's why I'm
co-maintaining mono-tools, monodevelop and now I'm also the maintainer
of f-spot. I'd like to provide good packages for the users and I'll try
my best to be responsive to any bug reports.

I've just started to walk through the f-spot bugs and I've found one
which reveals a more generic problem:

Bug https://bugzilla.redhat.com/show_bug.cgi?id=484996 claims, that the
f-spot package contains Provides for generic mono packages which are
bundled additionally with f-spot. This may or may not be reasonable, but
the real problem is, that the f-spot packages claims to provide e.g.

rpm -q --provides f-spot
[...]
mono(Mono.Addins) = 0.3.0.0
mono(Mono.Addins.Gui) = 0.3.0.0
mono(Mono.Addins.Setup) = 0.3.0.0
[...]

even though the assemblies are only locally to f-spot (and don't appear
in gac):

/usr/lib/f-spot/Mono.Addins.Gui.dll
/usr/lib/f-spot/Mono.Addins.Setup.dll
/usr/lib/f-spot/Mono.Addins.dll
/usr/lib/f-spot/Mono.Addins.dll.config
.

The problem is caused by the script /usr/lib/rpm/mono-find-provides
which is used by rpmbuild to extract the provides from the installed
files of the package.

All *.exe and *.dll files (which are _not_ in a documentation directory)
are scanned :

[...]
filelist=($(grep -Ev '/usr/doc/|/usr/share/doc/'))
monolist=($(printf "%s\n" "${filelist[@]}" | egrep
"\\.(exe|dll)\$"))
[...]

But I'm quite sure that this is wrong. The reason for this script is to
create the "mono(LIBRARY) = VERSION" provides. But a package should only
claim to provide a library, if it's really usable by other mono
libraries / programs. In general this should be only the libraries
located in %{_libdir}/mono  (which are most likely also added to the gac).

That's why I'd like to suggest the following patch:

--- /usr/lib/rpm/mono-find-provides     2009-05-18 13:26:14.000000000 +0200
+++ mono-find-provides        2009-07-17 11:47:02.000000000 +0200
@@ -10,7 +10,7 @@
 # Args: builddir buildroot libdir

 IFS=$'\n'
-filelist=($(grep -Ev '/usr/doc/|/usr/share/doc/'))
+filelist=($(grep -E '/usr/(lib|lib64)/mono/'))
 monolist=($(printf "%s\n" "${filelist[@]}" | egrep
"\\.(exe|dll)\$"))

 # If monodis is in the package being installed, use that one

This would make sure that only "usable" assemblies are claimed to be
provided by a package and problems like that the rpm database still
thinks that Mono.Addins are there just because f-spot is installed would
be gone.

What's your opinion about this? Would it make sense to request this
change in the rpm-build package first for rawhide and then later also
for F11 and F10? Or should I better use my own version in the f-spot
package for testing?

Any suggestions and comments are highly appreciated!

Best regards,
Christian

[Toshio Kuratomi]

On 07/17/2009 05:21 PM, Christian Krause wrote:
>  
>  Bug https://bugzilla.redhat.com/show_bug.cgi?id=484996 claims, that the
>  f-spot package contains Provides for generic mono packages which are
>  bundled additionally with f-spot. This may or may not be reasonable, but
>  the real problem is, that the f-spot packages claims to provide e.g.
>   
Actually I would reverse those.  The real problem is that packages are
not supposed to provide their own copies of generic packages.  But the
current find-provides script makes these issues apparent in a non-subtle
and end-user visible fashion.

>  
>  But I'm quite sure that this is wrong. The reason for this script is to
>  create the "mono(LIBRARY) = VERSION" provides. But a package should only
>  claim to provide a library, if it's really usable by other mono
>  libraries / programs. 
Yep, agreed.  Now I'm not a mono person so I'd appreciate information
about how it works:

* How does mono determine how to load a library at runtime?  is it a
combination of a default path, the MONO_PATH environment variable, and
anything in the GAC?  Is there more?  Is there less?  What's our default
path on Fedora?

* C libraries provide a mechanism to tell the dynamic linker that
there's other directories that it should add to the search path by
dropping files with the information in /etc/ld.so.d.  Does mono provide
equivalent functionality?

-Toshio