[rhythmbox] grilo: Fix crash due to lingering signal handler

[Victor Toso de Carvalho <victortoso src gnome org>]

commit d0e28c07b16969e611243edec9a26e151dfcca2f
Author: Victor Toso <me victortoso com>
Date:   Thu Aug 25 15:21:49 2016 +0200

    grilo: Fix crash due to lingering signal handler
    
    If the grilo rhythmbox plugin is deactivated and reactivated, the
    signal handler for "source-added" and "source-removed" will remain
    alive causing a crash as the previous RBGriloPlugin instance does not
    exist anymore.
    
    Backtrace:
     #0  0x00007f0f9af231c8 in __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:54
     #1  0x00007f0f9af2464a in __GI_abort () at abort.c:89
     #2  0x00007f0f9b7386a5 in g_assertion_message (domain=domain@entry=0x7f0f9b759fae "GLib", 
file=file@entry=0x7f0f9b75ec90 "/build/glib2.0-fJSoGg/glib2.0-2.48.1/./glib/ghash.c", line=line@entry=373,
         func=func@entry=0x7f0f9b75eed0 <__func__.10230> "g_hash_table_lookup_node", 
message=message@entry=0x3113c30 "assertion failed: (hash_table->ref_count > 0)")
         at ././glib/gtestutils.c:2429
     #3  0x00007f0f9b73873a in g_assertion_message_expr (domain=domain@entry=0x7f0f9b759fae "GLib", 
file=file@entry=0x7f0f9b75ec90 "/build/glib2.0-fJSoGg/glib2.0-2.48.1/./glib/ghash.c",
         line=line@entry=373, func=func@entry=0x7f0f9b75eed0 <__func__.10230> "g_hash_table_lookup_node", 
expr=expr@entry=0x7f0f9b75ebd8 "hash_table->ref_count > 0") at ././glib/gtestutils.c:2452
     #4  0x00007f0f9b701c4e in g_hash_table_lookup (hash_return=<synthetic pointer>, key=0x19ec730, 
hash_table=0x7f0f9ea9ca70) at ././glib/ghash.c:373
     #5  0x00007f0f9b701c4e in g_hash_table_lookup (hash_table=0x7f0f9ea9ca70, key=key@entry=0x19ec730) at 
././glib/ghash.c:1147
     #6  0x00007f0f74024c93 in grilo_source_removed_cb (registry=<optimized out>, grilo_source=0x19ec730 
[GrlBookmarksSource], plugin=0x277d370) at rb-grilo-plugin.c:161
    
    Reported-by: vrishab <vrishab in gmail com>
    
    https://bugzilla.gnome.org/show_bug.cgi?id=770044

 plugins/grilo/rb-grilo-plugin.c |   10 ++++++++--
 1 files changed, 8 insertions(+), 2 deletions(-)
---
diff --git a/plugins/grilo/rb-grilo-plugin.c b/plugins/grilo/rb-grilo-plugin.c
index 5c56b93..5b9287d 100644
--- a/plugins/grilo/rb-grilo-plugin.c
+++ b/plugins/grilo/rb-grilo-plugin.c
@@ -69,6 +69,8 @@ typedef struct
        RBShellPlayer *shell_player;
        gulong emit_cover_art_id;
        RBExtDB *art_store;
+       gulong handler_id_source_added;
+       gulong handler_id_source_removed;
 } RBGriloPlugin;
 
 typedef struct
@@ -211,8 +213,10 @@ impl_activate (PeasActivatable *plugin)
 
        grl_init (0, NULL);
        pi->registry = grl_registry_get_default ();
-       g_signal_connect (pi->registry, "source-added", G_CALLBACK (grilo_source_added_cb), pi);
-       g_signal_connect (pi->registry, "source-removed", G_CALLBACK (grilo_source_removed_cb), pi);
+       pi->handler_id_source_added =
+               g_signal_connect (pi->registry, "source-added", G_CALLBACK (grilo_source_added_cb), pi);
+       pi->handler_id_source_removed =
+               g_signal_connect (pi->registry, "source-removed", G_CALLBACK (grilo_source_removed_cb), pi);
        if (grl_registry_load_all_plugins (pi->registry, TRUE, &error) == FALSE) {
                g_warning ("Failed to load Grilo plugins: %s", error->message);
                g_clear_error (&error);
@@ -248,6 +252,8 @@ impl_deactivate     (PeasActivatable *bplugin)
        g_hash_table_destroy (plugin->sources);
        plugin->sources = NULL;
 
+       g_signal_handler_disconnect (plugin->registry, plugin->handler_id_source_added);
+       g_signal_handler_disconnect (plugin->registry, plugin->handler_id_source_removed);
        plugin->registry = NULL;
 
        if (plugin->emit_cover_art_id != 0) {