From b1691402bebfafba9c8055814493f55553f177c1 Mon Sep 17 00:00:00 2001

From: Tanu Kaskinen <tanuk@iki.fi>

Date: Wed, 16 Jan 2013 03:36:04 +0200

Subject: [PATCH 5/7] Initialize monitor's busy status to false if we own the

 device.

Bug found by David Henningsson.

---

 src/modules/reserve-monitor.c | 96 +++++++++++++++++++++++++++++++++++--------

 1 file changed, 80 insertions(+), 16 deletions(-)

diff --git a/src/modules/reserve-monitor.c b/src/modules/reserve-monitor.c

index 4097a6f..4aa4a2b 100644

--- a/src/modules/reserve-monitor.c

+++ b/src/modules/reserve-monitor.c

@@ -59,6 +59,23 @@ struct rm_monitor {

 	"member='NameOwnerChanged',"		\

 	"arg0='%s'"

+static unsigned get_busy(

+	DBusConnection *c,

+	const char *name_owner) {

+

+	const char *un;

+

+	if (!name_owner || !*name_owner)

+		return FALSE;

+

+	/* If we ourselves own the device, then don't consider this 'busy' */

+	if ((un = dbus_bus_get_unique_name(c)))

+		if (strcmp(name_owner, un) == 0)

+			return FALSE;

+

+	return TRUE;

+}

+

 static DBusHandlerResult filter_handler(

 	DBusConnection *c,

 	DBusMessage *s,

@@ -87,16 +104,7 @@ static DBusHandlerResult filter_handler(

 		if (strcmp(name, m->service_name) == 0) {

 			unsigned old_busy = m->busy;

-			m->busy = !!(new && *new);

-

-			/* If we ourselves own the device, then don't consider this 'busy' */

-			if (m->busy) {

-				const char *un;

-

-				if ((un = dbus_bus_get_unique_name(c)))

-					if (strcmp(new, un) == 0)

-						m->busy = FALSE;

-			}

+			m->busy = get_busy(c, new);

 			if (m->busy != old_busy && m->change_cb) {

 				m->ref++;

@@ -112,14 +120,71 @@ invalid:

 	return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;

 }

+static int get_name_owner(

+	DBusConnection *connection,

+	const char *name,

+	char **name_owner,

+	DBusError *error) {

+

+	DBusMessage *msg, *reply;

+	int r;

+

+	*name_owner = NULL;

+

+	if (!(msg = dbus_message_new_method_call(DBUS_SERVICE_DBUS, DBUS_PATH_DBUS, DBUS_INTERFACE_DBUS, "GetNameOwner"))) {

+		r = -ENOMEM;

+		goto fail;

+	}

+

+	if (!dbus_message_append_args(msg, DBUS_TYPE_STRING, &name, DBUS_TYPE_INVALID)) {

+		r = -ENOMEM;

+		goto fail;

+	}

+

+	reply = dbus_connection_send_with_reply_and_block(connection, msg, DBUS_TIMEOUT_USE_DEFAULT, error);

+	dbus_message_unref(msg);

+	msg = NULL;

+

+	if (reply) {

+		if (!dbus_message_get_args(reply, error, DBUS_TYPE_STRING, name_owner, DBUS_TYPE_INVALID)) {

+			dbus_message_unref(reply);

+			r = -EIO;

+			goto fail;

+		}

+

+		*name_owner = strdup(*name_owner);

+		dbus_message_unref(reply);

+

+		if (!*name_owner) {

+			r = -ENOMEM;

+			goto fail;

+		}

+

+	} else if (dbus_error_has_name(error, "org.freedesktop.DBus.Error.NameHasNoOwner"))

+		dbus_error_free(error);

+	else {

+		r = -EIO;

+		goto fail;

+	}

+

+	return 0;

+

+fail:

+	if (msg)

+		dbus_message_unref(msg);

+

+	return r;

+}

+

 int rm_watch(

 	rm_monitor **_m,

 	DBusConnection *connection,

-	const char*device_name,

+	const char *device_name,

 	rm_change_cb_t change_cb,

 	DBusError *error)  {

 	rm_monitor *m = NULL;

+	char *name_owner;

 	int r;

 	DBusError _error;

@@ -178,12 +243,11 @@ int rm_watch(

 	m->matching = 1;

-	m->busy = dbus_bus_name_has_owner(m->connection, m->service_name, error);

-

-	if (dbus_error_is_set(error)) {

-		r = -EIO;

+	if ((r = get_name_owner(m->connection, m->service_name, &name_owner, error)) < 0)

 		goto fail;

-	}

+

+	m->busy = get_busy(m->connection, name_owner);

+	free(name_owner);

 	*_m = m;

 	return 0;

-- 

1.8.1.4