Remove AppImage environment overrides before switching mods

OpenRA.Game/Game.cs

@@ -41,6 +41,7 @@ public static class Game
 		public static ICursor Cursor;
 		public static bool HideCursor;
 		static WorldRenderer worldRenderer;
+		static string modLaunchWrapper;
 
 		internal static OrderManager OrderManager;
 		static Server.Server server;
@@ -351,6 +352,8 @@ static void Initialize(Arguments args)
 			foreach (var mod in Mods)
 				Console.WriteLine("\t{0}: {1} ({2})", mod.Key, mod.Value.Metadata.Title, mod.Value.Metadata.Version);
 
+			modLaunchWrapper = args.GetValue("Engine.LaunchWrapper", null);
+
 			ExternalMods = new ExternalMods();
 
 			Manifest currentMod;
@@ -509,8 +512,15 @@ public static void SwitchToExternalMod(ExternalMod mod, string[] launchArguments
 		{
 			try
 			{
+				var path = mod.LaunchPath;
 				var args = launchArguments != null ? mod.LaunchArgs.Append(launchArguments) : mod.LaunchArgs;
-				var p = Process.Start(mod.LaunchPath, args.Select(a => "\"" + a + "\"").JoinWith(" "));
+				if (modLaunchWrapper != null)
+				{
+					path = modLaunchWrapper;
+					args = new[] { mod.LaunchPath }.Concat(args);
+				}
+
+				var p = Process.Start(path, args.Select(a => "\"" + a + "\"").JoinWith(" "));
 				if (p == null || p.HasExited)
 					onFailed();
 				else

packaging/linux/AppRun.in

@@ -2,11 +2,21 @@
 
 HERE="$(dirname "$(readlink -f "${0}")")"
 
-# Override runtime paths
+# Stash original environment values so they can be restored
+# when switching to other mods using restore-environment
+export OPENRA_ORIG_PATH="${PATH}"
+export OPENRA_ORIG_XDG_DATA_DIRS="${XDG_DATA_DIRS}"
+export OPENRA_ORIG_DYLD_LIBRARY_PATH="${DYLD_LIBRARY_PATH}"
+export OPENRA_ORIG_LD_LIBRARY_PATH="${LD_LIBRARY_PATH}"
+export OPENRA_ORIG_MONO_PATH="${MONO_PATH}"
+export OPENRA_ORIG_MONO_CFG_DIR="${MONO_CFG_DIR}"
+export OPENRA_ORIG_MONO_CONFIG="${MONO_CONFIG}"
+
+# Override runtime paths to use bundled mono and shared libraries
 export PATH="${HERE}/usr/bin:${PATH}"
 export XDG_DATA_DIRS="${HERE}/usr/share:${XDG_DATA_DIRS}"
-export DYLD_LIBRARY_PATH="${HERE}/usr/lib:$DYLD_LIBRARY_PATH"
-export LD_LIBRARY_PATH="${HERE}/usr/lib:$LD_LIBRARY_PATH"
+export DYLD_LIBRARY_PATH="${HERE}/usr/lib:${DYLD_LIBRARY_PATH}"
+export LD_LIBRARY_PATH="${HERE}/usr/lib:${LD_LIBRARY_PATH}"
 export MONO_PATH="${HERE}/usr/lib/mono/4.5"
 export MONO_CFG_DIR="${HERE}/etc"
 export MONO_CONFIG="${HERE}/etc/mono/config"

packaging/linux/buildpackage.sh

@@ -140,6 +140,8 @@ build_appimage() {
 
 	install -m 0755 gtk-dialog.py "${APPDIR}/usr/bin/gtk-dialog.py"
 
+	install -m 0755 restore-environment.sh "${APPDIR}/usr/bin/restore-environment.sh"
+
 	# travis-ci doesn't support mounting FUSE filesystems so extract and run the contents manually
 	./appimagetool-x86_64.AppImage --appimage-extract
 

packaging/linux/openra.appimage.in

@@ -5,7 +5,7 @@ cd "${HERE}/../lib/openra" || exit 1
 
 # APPIMAGE is an environment variable set by the runtime
 # defining the absolute path to the .AppImage file
-if [ ! -z "${APPIMAGE}" ]; then
+if [ -n "${APPIMAGE}" ]; then
   LAUNCHER=${APPIMAGE}
 
   # appimaged doesn't update the mime or icon caches when registering AppImages.
@@ -35,7 +35,7 @@ fi
 
 # Run the game
 export SDL_VIDEO_X11_WMCLASS="openra-{MODID}-{TAG}"
-mono --debug OpenRA.Game.exe Game.Mod={MODID} Engine.LaunchPath="${LAUNCHER}" "${JOIN_SERVER}" "$@"
+mono --debug OpenRA.Game.exe Game.Mod={MODID} Engine.LaunchPath="${LAUNCHER}" Engine.LaunchWrapper="${HERE}/restore-environment.sh" "${JOIN_SERVER}" "$@"
 
 # Show a crash dialog if something went wrong
 if [ $? != 0 ] && [ $? != 1 ]; then

packaging/linux/restore-environment.sh

@@ -0,0 +1,26 @@
+#!/bin/sh
+
+# Restore the environment variables that were set by AppRun
+export PATH="${OPENRA_ORIG_PATH}"
+export XDG_DATA_DIRS="${OPENRA_ORIG_XDG_DATA_DIRS}"
+export DYLD_LIBRARY_PATH="${OPENRA_ORIG_DYLD_LIBRARY_PATH}"
+export LD_LIBRARY_PATH="${OPENRA_ORIG_LD_LIBRARY_PATH}"
+unset OPENRA_ORIG_PATH OPENRA_ORIG_XDG_DATA_DIRS OPENRA_ORIG_DYLD_LIBRARY_PATH OPENRA_ORIG_LD_LIBRARY_PATH
+
+unset MONO_PATH MONO_CFG_DIR MONO_CONFIG
+if [ -n "${OPENRA_ORIG_MONO_PATH}" ]; then
+  export MONO_PATH="${OPENRA_ORIG_MONO_PATH}"
+fi
+
+if [ -n "${OPENRA_ORIG_MONO_CFG_DIR}" ]; then
+  export MONO_CFG_DIR="${OPENRA_ORIG_MONO_CFG_DIR}"
+fi
+
+if [ -n "${OPENRA_ORIG_MONO_CONFIG}" ]; then
+  export MONO_CONFIG="${OPENRA_ORIG_MONO_CONFIG}"
+fi
+
+unset SDL_VIDEO_X11_WMCLASS OPENRA_ORIG_MONO_PATH OPENRA_ORIG_MONO_CFG_DIR OPENRA_ORIG_MONO_CONFIG
+
+# Run the given command
+exec "$@"