From b3c18fe2be0e0078c7b8de9f331357227ccddc39 Mon Sep 17 00:00:00 2001
From: Guillaume Bouchard <guillaum.bouchard@gmail.com>
Date: Mon, 4 May 2020 14:39:44 +0200
Subject: apitrace: fix OpenGL library path and Qt GUI (#86475)

For unknown reasons, Apitrace breaks the runpath of the traced program.
OpenGL programs on nix are looking at /run/opengl-driver/lib to find the
system OpenGL driver.

This change:

- add path /run/opengl-driver{-32} to the RPATH of the wrapper
libraries. This fixs tracing with `apitrace trace`.
- add rpath to `libglnvd` and `libGL` to the `{e}glretrace` binaries.
These libraries are loaded at runtime, but does not appears as NEEDED in
the binaries, hence the need for the explicit rpath addition. This fix
`{e}glretrace`.
- Explicitly add Qt wrapper to `qapitrace`. It fixs the GUI.

Co-authored-by: Florian Klink <flokli@flokli.de>

Co-authored-by: Florian Klink <flokli@flokli.de>
---
 pkgs/applications/graphics/apitrace/default.nix | 45 +++++++++++++++++++++++--
 1 file changed, 43 insertions(+), 2 deletions(-)

diff --git a/pkgs/applications/graphics/apitrace/default.nix b/pkgs/applications/graphics/apitrace/default.nix
index f6f9cb281a772..e6865d2d8f07a 100644
--- a/pkgs/applications/graphics/apitrace/default.nix
+++ b/pkgs/applications/graphics/apitrace/default.nix
@@ -1,4 +1,4 @@
-{ stdenv, fetchFromGitHub, cmake, libX11, procps, python2, libdwarf, qtbase, qtwebkit }:
+{ stdenv, fetchFromGitHub, cmake, libX11, procps, python2, libdwarf, qtbase, qtwebkit, wrapQtAppsHook, libglvnd }:
 
 stdenv.mkDerivation rec {
   pname = "apitrace";
@@ -15,7 +15,48 @@ stdenv.mkDerivation rec {
   # of games -- so it's fine to use e.g. bundled snappy.
   buildInputs = [ libX11 procps python2 libdwarf qtbase qtwebkit ];
 
-  nativeBuildInputs = [ cmake ];
+  nativeBuildInputs = [ cmake wrapQtAppsHook ];
+
+  # Don't automatically wrap all binaries, I prefer to explicitly only wrap
+  # `qapitrace`.
+  dontWrapQtApps = true;
+
+  postFixup = ''
+
+    # Since https://github.com/NixOS/nixpkgs/pull/60985, we add `/run-opengl-driver[-32]`
+    # to the `RUNPATH` of dispatcher libraries `dlopen()` ing OpenGL drivers.
+    # `RUNPATH` doesn't propagate throughout the whole application, but only
+    # from the module performing the `dlopen()`.
+    # 
+    # Apitrace wraps programs by running them with `LD_PRELOAD` pointing to `.so`
+    # files in $out/lib/apitrace/wrappers.
+    # 
+    # Theses wrappers effectively wrap the `dlopen()` calls from `libglvnd`
+    # and other dispatcher libraries, and run `dlopen()`  by themselves.
+    # 
+    # As `RUNPATH` doesn't propagate through the whole library, and they're now the
+    # library doing the real `dlopen()`, they also need to have
+    # `/run-opengl-driver[-32]` added to their `RUNPATH`.
+    #
+    # To stay simple, we add paths for 32 and 64 bits unconditionally.
+    # This doesn't have an impact on closure size, and if the 32 bit drivers
+    # are not available, that folder is ignored.
+    for i in $out/lib/apitrace/wrappers/*.so
+    do
+      echo "Patching OpenGL driver path for $i"
+      patchelf --set-rpath "/run/opengl-driver/lib:/run/opengl-driver-32/lib:$(patchelf --print-rpath $i)" $i
+    done
+
+    # Theses open the OpenGL driver at runtime, but it is not listed as NEEDED libraries. They need
+    # a reference to libglvnd.
+    for i in $out/bin/eglretrace $out/bin/glretrace
+    do
+      echo "Patching RPath for $i"
+      patchelf --set-rpath "${stdenv.lib.makeLibraryPath [libglvnd]}:$(patchelf --print-rpath $i)" $i
+    done
+
+    wrapQtApp $out/bin/qapitrace
+  '';
 
   meta = with stdenv.lib; {
     homepage = "https://apitrace.github.io";
-- 
cgit 1.4.1