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From c06ce2520886d42e3489c6a4abf5735e6bb080b9 Mon Sep 17 00:00:00 2001
From: Debarshi Ray <debarshir@freedesktop.org>
Date: Mon, 19 Jan 2015 19:24:05 +0100
Subject: [PATCH] [Connector] Don't crash when trying to unwatch non-existent
 client

$ gdbus call \
    --session \
    --dest com.intel.dleyna-renderer \
    --object-path /com/intel/dLeynaRenderer \
    --method com.intel.dLeynaRenderer.Manager.Release

If a service is spawned as a result of the above command, then it will
lead to a crash with this backtrace:

    (client_name=0x7f7c94009750 ":1.603") at src/connector-dbus.c:271
    (conn=<optimized out>, sender=0x7f7c94009750 ":1.603",
    object=<optimized out>, interface=<optimized out>,
    method=<optimized out>, parameters=<optimized out>,
    invocation=0x2360e00) at server.c:780
    at gdbusconnection.c:4884
    at gmain.c:3111
    (context=context@entry=0x2342ea0) at gmain.c:3710
    block=block@entry=1, dispatch=dispatch@entry=1,
    self=<optimized out>) at gmain.c:3781
    at gmain.c:3975
    (server=<optimized out>, control_point=<optimized out>,
    user_data=0x0) at libdleyna/core/main-loop.c:155
    argv=<optimized out>) at daemon.c:93

This is because g_hash_table_lookup returns NULL which we try to
dereference to get the client_id.

Instead of our hand-spun solution for storing unsigned integers in a
GHashTable, let's use standard GLib mechanisms for doing that. We
avoid this problem and reduce a g_new/g_free pair as a bonus.
---
 src/connector-dbus.c | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/src/connector-dbus.c b/src/connector-dbus.c
index 0e16239..83774c0 100644
--- a/src/connector-dbus.c
+++ b/src/connector-dbus.c
@@ -173,7 +173,7 @@ static gboolean prv_connector_initialize(const gchar *server_info,
 	g_context.objects = g_hash_table_new_full(g_direct_hash, g_direct_equal,
 						  g_free, prv_free_dbus_object);
 	g_context.clients = g_hash_table_new_full(g_str_hash, g_str_equal,
-						  g_free, g_free);
+						  g_free, NULL);
 
 	g_context.root_node_info = g_dbus_node_info_new_for_xml(root_info,
 								NULL);
@@ -268,8 +268,8 @@ static void prv_connector_unwatch_client(const gchar *client_name)
 
 	DLEYNA_LOG_DEBUG("Enter");
 
-	client_id = *(guint *)g_hash_table_lookup(g_context.clients,
-						  client_name);
+	client_id = GPOINTER_TO_UINT(g_hash_table_lookup(g_context.clients,
+							 client_name));
 	(void) g_hash_table_remove(g_context.clients, client_name);
 
 	g_bus_unwatch_name(client_id);
@@ -287,7 +287,6 @@ static void prv_lost_client(GDBusConnection *connection, const gchar *name,
 static gboolean prv_connector_watch_client(const gchar *client_name)
 {
 	guint watch_id;
-	guint *client_id;
 	gboolean added = TRUE;
 
 	DLEYNA_LOG_DEBUG("Enter");
@@ -301,10 +300,8 @@ static gboolean prv_connector_watch_client(const gchar *client_name)
 				      G_BUS_NAME_WATCHER_FLAGS_NONE,
 				      NULL, prv_lost_client, NULL,
 				      NULL);
-	client_id = g_new(guint, 1);
-	*client_id = watch_id;
 	g_hash_table_insert(g_context.clients, g_strdup(client_name),
-			    client_id);
+			    GUINT_TO_POINTER(watch_id));
 
 out:
 	DLEYNA_LOG_DEBUG("Exit");
-- 
2.1.0