From cdf55502bed9739777ae8e517e145d3ea7a9e9b0 Mon Sep 17 00:00:00 2001
From: Simon McVittie <simon.mcvittie@collabora.co.uk>
Date: Thu, 29 Jan 2015 12:48:49 +0000
Subject: [PATCH 3/5] On Unix platforms, try $XDG_RUNTIME_DIR/bus before
 default address

Based on part of a patch by Colin Walters. Changes:
- set error correctly on OOM
- escape the path if it contains inconvenient characters
- coding style adjustments

Bug: https://bugs.freedesktop.org/show_bug.cgi?id=61303
---
 dbus/dbus-sysdeps-unix.c | 53 +++++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 50 insertions(+), 3 deletions(-)

diff --git a/dbus/dbus-sysdeps-unix.c b/dbus/dbus-sysdeps-unix.c
index f4a42d8..c89cb59 100644
--- a/dbus/dbus-sysdeps-unix.c
+++ b/dbus/dbus-sysdeps-unix.c
@@ -29,6 +29,7 @@
 #include "dbus-sysdeps-unix.h"
 #include "dbus-threads.h"
 #include "dbus-protocol.h"
+#include "dbus-file.h"
 #include "dbus-transport.h"
 #include "dbus-string.h"
 #include "dbus-userdb.h"
@@ -3861,10 +3862,56 @@ _dbus_lookup_session_address (dbus_bool_t *supported,
   *supported = TRUE;
   return _dbus_lookup_session_address_launchd (address, error);
 #else
+  const char *runtime_dir = _dbus_getenv ("XDG_RUNTIME_DIR");
+  dbus_bool_t ret = FALSE;
+
+  if (runtime_dir != NULL)
+    {
+      struct stat stbuf;
+      DBusString user_bus_path;
+
+      if (!_dbus_string_init (&user_bus_path))
+        {
+          _DBUS_SET_OOM (error);
+          return FALSE;
+        }
+
+      if (!_dbus_string_append_printf (&user_bus_path,
+            "%s/dbus/user_bus_socket", runtime_dir))
+        {
+          _DBUS_SET_OOM (error);
+          goto runtime_out;
+        }
+
+      if (lstat (_dbus_string_get_const_data (&user_bus_path), &stbuf) != -1)
+        {
+          if (!_dbus_string_append (address, "unix:path=") ||
+              !_dbus_address_append_escaped (address, &user_bus_path))
+            {
+              _DBUS_SET_OOM (error);
+              goto runtime_out;
+            }
+
+          *supported = TRUE;
+          ret = TRUE;
+        }
+      else
+        {
+          /* Not an error */
+          *supported = FALSE;
+          ret = TRUE;
+        }
+
+runtime_out:
+      _dbus_string_free (&user_bus_path);
+      return ret;
+    }
+
   /* On non-Mac Unix platforms, if the session address isn't already
-   * set in DBUS_SESSION_BUS_ADDRESS environment variable, we punt and
-   * fall back to the autolaunch: global default; see
-   * init_session_address in dbus/dbus-bus.c. */
+   * set in DBUS_SESSION_BUS_ADDRESS environment variable and the
+   * $XDG_RUNTIME_DIR/bus can't be used, we punt and fall back to the
+   * autolaunch: global default; see init_session_address in
+   * dbus/dbus-bus.c. */
   *supported = FALSE;
   return TRUE;
 #endif
-- 
2.1.4