Hi Michael,
On 03/05/2023 17:39, Michael Tremer wrote:
Hello Adolf,
On 3 May 2023, at 14:23, Adolf Belka adolf.belka@ipfire.org wrote:
Hi Michael,
On 03/05/2023 14:58, Adolf Belka wrote:
On 03/05/2023 14:35, Adolf Belka wrote:
Hi Michael,
On 03/05/2023 14:07, Michael Tremer wrote:
Hello Adolf,
Normally you should not need to add anything extra for this to work. The compiler should know where to search for libraries.
If pkg-config is being used, this might be a little bit different.
Just before the various packages are checked to exist the configure also checks that pkg-config is existing.
On 3 May 2023, at 13:02, Adolf Belka adolf.belka@ipfire.org wrote:
Hi All,
There is a new version for rng-tools so I thought I would do an update but it kept stopping saying that it required libcap and could not find it.
I noted that the libcap libs are in /lib and not in /usr/lib as the other packages that rng-tools looks for have their libs. (openssl, libxml2, curl, jansson)
The new version has a flag for the ./configure called libcap_LIBS which can be used to override pkg-config.
I tried that in various ways such as libcap_LIBS="/lib" or libcap_LIBS="/lib/libcap.so.2.67" and others, but none of them worked. The ./configure still ended up with the message
checking for libcap... no configure: error: libcap is required
I then noticed that libcap.pc is in /lib/pkgconfig/ while all the other packages being searched for are in /usr/lib/pkgconfig/
This should indeed be installed to /usr/lib/pkgconfig.
I don’t have a problem with simply changing —-prefix=/ to —-prefix=/usr for libcap, because we don’t support a split /usr directory anyways. That should make it easier.
Looking through the libcap README and Makefile then the .pc files should be getting placed in /usr/lib/pkgconfig but they aren't. Also as $(prefix) is not defined then the prefix should be /usr but again it is not.
I think I must have misread what the Makefile etc were intending to do.
I just tried a quick build of libcap with adding prefix=/usr to the make and make install lines and the lib files and the .pc files are now in /usr/lib/ and /usr/lib/pkgconfig/
The only remaining question I have is if anything else in IPFire would be expecting to see the lib files for libcap in /lib/ instead of /usr/lib/ because then the symlinking of the lib from /lib/ to /usr/lib/ won't be needed any more.
No, pkg-config should never search in /lib.
Okay, that is good to know.
What is libcap used for so I can test out the built iso on a vm machine?
It is quite widely used to manage capabilities of a running program. I can give some privileges away and limit itself so that any remote code executing could not cause too much damage for example.
/usr/bin/ping is for example linked against libcap. If you can execute it, everything is fine.
That is a nice easy test then.
The build of libcap with prefix=/usr successfully built but it also placed the capsh, getcap, getpcaps and setcap binaries from /sbin to /usr/sbin so the change was not as easy as I thought. Maybe I should only have the prefix=/usr in the make line and not in the make install line.
Will have another look in the makefile and see how the location for capsh etc are defined.
Regards, Adolf.
Regards,
Adolf.
libcap currently keeps the library files in /lib/ but makes a symlink to one of them in /usr/lib/. Libcap doesn't have a configure line. There is a sed command on the Makefile to stop it building static libs and then it goes straight to make and then make install
I then manually did a copy of libcap.pc to /usr/lib/pkgconfig/ and then re ran just the rng-tools build and it then successfully found libcap and completed the build. So the problem is definitely to do withy the unusual location for the library files of libcap.
Do we have any other packages that install .pc files into funny places?
The other .pc files that are in /lib/pkgconfig/ are libkeyutils, libproc-2, libpsx and libsysfs
The libpsx.pc file is also from libcap.
So the question I have is what is the best way to deal with this.
Should I add into the libcap lfs a line that copies the libcap.pc to /usr/lib/pkgconfig/ or
is can someone tell me what I am doing wrong with the libcap_LIBS flag for ./configure
I think that rather than trying to adjust libcap to work the way it says it should be anyway, I will add a copy line into the lfs to move the libcap.pc file to /usr/lib/pkgconfig/
Regards,
Adolf.
Regards,
Adolf.
-Michael