[gnome-session] gsm-util: save environment to $XDG_RUNTIME_DIR/gnome/environment

[Ray Strode <halfline src gnome org>]

commit db7ce81e9acd5859cb929496e39880d8b4fdc1bf
Author: Ray Strode <rstrode redhat com>
Date:   Wed Sep 16 14:51:20 2015 -0400

    gsm-util: save environment to $XDG_RUNTIME_DIR/gnome/environment
    
    Environment variables are problematic because they require a parent
    child inheritance model, but they're often used in a per-session scope.
    
    gnome-session provides a mechanism for children to affect the
    environment of future siblings via the SetEnv dbus method call.
    Unfortunately that change does not affect existing siblings, or their
    offspring.
    
    This commit centralizes gnome-session's environment into a file,
    
         $XDG_RUNTIME_DIR/gnome/environment
    
    so other components in the session can ensure their children get the
    most up to date environment possible.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=738205

 gnome-session/gsm-util.c |   35 +++++++++++++++++++++++++++++++++++
 1 files changed, 35 insertions(+), 0 deletions(-)
---
diff --git a/gnome-session/gsm-util.c b/gnome-session/gsm-util.c
index b7d2cda..bca1b38 100644
--- a/gnome-session/gsm-util.c
+++ b/gnome-session/gsm-util.c
@@ -447,6 +447,39 @@ gsm_util_generate_startup_id (void)
                                 sequence);
 }
 
+static void
+gsm_util_save_environment (void)
+{
+        g_autoptr(GVariant)  environment = NULL;
+        g_autoptr(GError)    error = NULL;
+        g_autofree char     *environment_dir = NULL;
+        g_autofree char     *filename = NULL;
+        gconstpointer        environment_data;
+        gsize                size;
+        int                  ret;
+        gboolean             contents_set;
+
+        environment_dir = g_build_filename (g_get_user_runtime_dir (), "gnome", NULL);
+        ret = g_mkdir_with_parents (environment_dir, 0700);
+
+        if (ret < 0) {
+                g_warning ("can't create gnome runtime dir: %m");
+                return;
+        }
+
+        environment = g_variant_new_bytestring_array ((const gchar * const *) g_get_environ (), -1);
+        size = g_variant_get_size (environment);
+        environment_data = g_variant_get_data (environment);
+
+        filename = g_build_filename (environment_dir, "environment", NULL);
+
+        contents_set = g_file_set_contents (filename, environment_data, size, &error);
+
+        if (!contents_set) {
+                g_warning ("can't save environment: %s", error->message);
+        }
+}
+
 static gboolean
 gsm_util_update_activation_environment (const char  *variable,
                                         const char  *value,
@@ -511,4 +544,6 @@ gsm_util_setenv (const char *variable,
                 g_warning ("Could not make bus activated clients aware of %s=%s environment variable: %s", 
variable, value, bus_error->message);
                 g_error_free (bus_error);
         }
+
+        gsm_util_save_environment ();
 }