OpenGL: unable to open display

[guibou]

nix-bundle blender /bin/blender

Will fail with:

$ ./blender          
Unable to open a display
../run: line 1: 27203 Aborted                 ./nix/store/c1x6kjxjvbjzqzjcv38ni5mb9zpb7khx-nix-user-chroot-2b144e/bin/nix-user-chroot ./nix /nix/store/1fqm7lqkjdkcfdj1fz9b7n0xizznqy82-blender-2.79/bin/blender $@

On nixos 17.09.1997.1a8a95e879 (Hummingbird) using the packaged nix-bundle.

[matthewbauer]

So my bet is that some env var is not available in the container. We set a few here:

https://github.com/matthewbauer/nix-bundle/blob/master/AppRun.c#L231-L242

Something to try would be to run strace and see if it's trying to access a file that's not in the mount namespace.

[matthewbauer]

Okay my latest commit should fix this. To test it:

git clone https://github.com/matthewbauer/nix-bundle
cd nix-bundle
./nix-bundle.sh blender /bin/blender

[guibou]

It does not unfortunately. Tested on nixos and arch linux (the nix-bundle call was done on nixos and the file was transfered to arch by ssh).

I tried with something "simpler", glxinfo and it is the same:

[guillaume@skolem:/tmp/nix-bundle]$ git describe --tags
v0.2.0-4-gaa4d9f9

[guillaume@skolem:/tmp/nix-bundle]$ ./nix-bundle.sh glxinfo /bin/glxinfo
Nix bundle created at glxinfo.

[guillaume@skolem:/tmp/nix-bundle]$ ./glxinfo
No protocol specified
Error: unable to open display :0

[matthewbauer]

Ok so adding the /tmp dir in the latest commit gets us a little farther:

name of display: :0
libGL error: unable to load driver: swrast_dri.so
libGL error: failed to load driver: swrast
X Error of failed request:  GLXBadContext
  Major opcode of failed request:  154 (GLX)
  Minor opcode of failed request:  6 (X_GLXIsDirect)
  Serial number of failed request:  48
  Current serial number in output stream:  47

I wonder why it can't find the driver?

[guibou]

Ok, stuff starts to be really interesting.

The status of OpenGL on nix/nixos is a bit broken. OpenGL is a system library (and impure by definition), and the mesa package contains a hack to find the libGL in /run/opengl-drivers and nixos runs a boot-time service which sets symbolic links in this directory. More details here:

• (issue discussion): libGL not working on non-NixOS (without setting up) NixOS/nixpkgs#9415 (comment)
• (one attempt of a fix, smart idea, need more support, complex): https://github.com/deepfire/nix-install-vendor-gl
• (Another attempt, stupid idea (mine ;), simple, but with lot of limitations): https://github.com/guibou/nixGL

I don't know about the internal of nix-bundle, but to work with OpenGL, it needs, at least, to give an access to the host system /run/opengl-drivers, so it will work on nixos or any system where nix is installed and the user created the symbolic link. But this is a wrong solution because it means that nix-bundle will only work for OpenGL application on system where nix is already installed, which defeat the purpose of nix-bundle.

A robust solution will be to locate the system libGL (usually in /usr/lib/libGL.so, but not always) and use it, and all of its dependencies.

[Radvendii]

Is there any progress on this? Or a workaround? Is it just not possible to package graphical apps with nix-bundle?

I am trying to package a game I'm making using nix-bundle, and I'm getting the error "Couldn't find matching GLX visual", which I'm assuming is the same issue described here.

I was able to get it working by wrapping the package in a call to nixGL before wrapping it in nix-bundle, but as mentioned in the issue above, this seems incredibly non-portable.

[Radvendii]

I was actually able to solve this issue for AppImage by updating the AppRun.c file to the latest from AppImageKit (https://github.com/AppImage/AppImageKit/blob/master/src/AppRun.c). I have the same issue with a non-appimage bundle, and I don't see AppRun.c referenced anywhere from that code, so I'm guessing the two were unrelated?

[arximboldi]

@Radvendii when I do that I get Error executing '<program>': no such file or directory where <program> is the name of the binary of the app I am packaging. Did you do anything else to get it working?

[Radvendii]

@arximboldi I don't remember the minimal changes to get this part of things working, but I actually wound up doing a bunch of work on the appimage infrastructure. You can see my PR here #76, and try it out by referring to my fork of nix-bundle https://github.com/radvendii/nix-bundle

[arximboldi]

Thank you so much @Radvendii!! I'm gonna definitelly take a look!

[arximboldi]

@Radvendii, I just tried that PR and I am having the same issue. I'm writing with more details in the PR.