After bumping sublime3 in #61636 we realized that saving files as root
doesn’t work anymore and somehow the paths weren’t patched by
`libredirect`.
After some debugging it came out that Sublime switched from `posix_spawn(3)`
to `posix_spawnp(3)` to start new processes internally. Since `libredirect`
only handled the former, `/usr/bin/pkexec` stopped being redirected.
Wrapping `posix_spawnp` fixes the problem.
While it might be useful in some cases, there are too many caveats to be worth it.
When libredirect intercepts dlopen call and calls the original function, the dynamic
loader will use libredirect.so's DT_RUNPATH entry instead of the one from the ELF file
the dlopen call originated from. That means that when program tries to dlopen a library
that it expects to find on its RPATH, the call will fail.
This broke Sublime Text for just that reason.
gobject-introspection uses glib’s g_module_open function, which in turn relies
on dlopen. I also implemented openat, since I initially thought this function
was used but turns out dlopen uses the openat signal directly. We might as
well keep it, even thought I do not need it at the moment.
This allows to simplify the usage of libredirect inside of nix build
sandboxes. Add "libredirect.hook" to the build inputs to get everything
linked in automaticall. All that's left is to set NIX_REDIRECTS and call
the target program.
Pull request #50246 was merged a bit too quickly and it was supposed to
fix libredirect on Darwin. However it still failed on Darwin and this
was missed by the person merging the pull request.
The reason this was failing was that there is no __xstat* on Darwin.
So I'm adding a wrapper for stat() as well as it works on Darwin and it
still doesn't hurt on GNU/Linux.
Signed-off-by: aszlig <aszlig@nix.build>
Cc: @edolstra, @zimbatm
This is just a sanity check on whether the library correctly wraps the
syscalls and it's using the "true" executable for posix_spawn() and
execv().
The installCheckPhase is not executed if we are cross-compiling, so this
shouldn't break cross-compilation.
One thing I'm not actually sure is whether ${coreutils}/bin/true is
universally available on all the platforms, nor whether all the
functions we use in the test are available, but we can still fix that
after we've found out about that.
Signed-off-by: aszlig <aszlig@nix.build>
This is to make sure we get the correct shared library suffix of the
target platform. While for example on Darwin it would even work with the
hardcoded .so prefix it's IMHO a bit nicer to have the actual native
extension.
Signed-off-by: aszlig <aszlig@nix.build>
The library can be used also on Darwin using it like this:
NIX_REDIRECTS='foo=bar' \
DYLD_INSERT_LIBRARIES=${libredirect}/lib/libredirect.so \
DYLD_FORCE_FLAT_NAMESPACE=1 \
some_program
So let's actually not hardcade gcc and add Darwin to meta.platforms.
No other changes seem to be required.
Signed-off-by: aszlig <aszlig@nix.build>
HipChat (or rather its copy of Qt) expects to find keyboard data in
/usr/share/X11/xkb. So use a LD_PRELOAD library to intercept and
rewrite the Glibc calls that access those paths. We've been doing the
same thing with packages like Spotify, but now this functionality has
been abstracted into a reusable library, libredirect.so. It uses an
environment variable $NIX_REDIRECTS containing a colon-separated list
of path prefixes to be rewritten, e.g. "/foo=bar:/xyzzy=/fnord".
