From 4de2d31e9175105324526f010b831c2ec9ca9b9e Mon Sep 17 00:00:00 2001
From: Gregor Lohaus <gregor.lohaus@8mylez.com>
Date: Fri, 29 May 2026 12:51:45 +0200
Subject: [PATCH] clear env, dont inherit nix wrapper env

---
 flake.nix                                     |  1 +
 .../com/gregor/jprototerm/ShellSession.java   | 25 +++++++++++++++++++
 2 files changed, 26 insertions(+)

diff --git a/flake.nix b/flake.nix
index 33e182c..45ba01e 100644
--- a/flake.nix
+++ b/flake.nix
@@ -108,6 +108,7 @@
               done
 
               makeWrapper "${pkgs.jdk25}/bin/java" "$out/bin/jprototerm" \
+                --run 'export JPROTOTERM_HOST_LD_LIBRARY_PATH="''${LD_LIBRARY_PATH:-}"' \
                 --add-flags "--enable-native-access=ALL-UNNAMED,javafx.graphics" \
                 --add-flags "--module-path $out/share/jprototerm/javafx" \
                 --add-flags "--add-modules javafx.controls,javafx.fxml" \
diff --git a/src/main/java/com/gregor/jprototerm/ShellSession.java b/src/main/java/com/gregor/jprototerm/ShellSession.java
index d787383..5ee7514 100644
--- a/src/main/java/com/gregor/jprototerm/ShellSession.java
+++ b/src/main/java/com/gregor/jprototerm/ShellSession.java
@@ -27,6 +27,7 @@ public final class ShellSession implements AutoCloseable {
             Map<String, String> environment = new HashMap<>(System.getenv());
             environment.put("TERM", "xterm-kitty");
             environment.put("COLORTERM", "truecolor");
+            sanitizeWrapperEnvironment(environment);
             environment.putAll(envOverride);
 
             LinuxPty pty = LinuxPty.spawn(
@@ -42,6 +43,30 @@ public final class ShellSession implements AutoCloseable {
         }
     }
 
+    /**
+     * Strips the variables injected by the Nix launcher wrapper from the shell's
+     * environment so they do not leak into terminal subprocesses.
+     *
+     * <p>jprototerm is launched from a Nix wrapper that prepends Nix store paths to
+     * {@code LD_LIBRARY_PATH} (and adds a GL shim) so the bundled JavaFX/ghostty natives
+     * resolve. If the shell inherited that path, host programs run inside the terminal
+     * (e.g. {@code flatpak}, {@code pdftoppm}) would load the Nix copies of libraries such
+     * as freetype/fontconfig/glib, which in turn drag in the Nix glibc through their
+     * RUNPATHs and clash with the host {@code libc.so.6}. We restore the user's original
+     * {@code LD_LIBRARY_PATH}, captured by the wrapper before it prepended anything.
+     */
+    private static void sanitizeWrapperEnvironment(Map<String, String> environment) {
+        String hostLibraryPath = environment.remove("JPROTOTERM_HOST_LD_LIBRARY_PATH");
+        if (hostLibraryPath == null || hostLibraryPath.isEmpty()) {
+            environment.remove("LD_LIBRARY_PATH");
+        } else {
+            environment.put("LD_LIBRARY_PATH", hostLibraryPath);
+        }
+        // These are jprototerm's own runtime settings, not the user's shell environment.
+        environment.remove("GDK_BACKEND");
+        environment.remove("JLIBGHOSTTY_LIBRARY");
+    }
+
     public void startReading(TerminalPane pane) {
         reader.submit(() -> readOutput(pane));
     }