port-qmi: implement the new generic 'removed' signal

Letting the MMBroadbandModemQmi listen for the notifications of the
QmiDevice was not a good idea, especially since no explicit reference
to the device object was hold in the modem object. This leads to race
conditions in which the QmiDevice outlives the MMBroadbandModemQmi and
the MMPortQmi, and when the "device-removed" signal is triggered, the
program crashes.

The MMPortQmi will now emit its own 'removed' signals when the
underlying QmiDevice emits "device-removed', ensuring that the signal
handler is properly cleared up during the MMPortQmi disposal.

1 files changed, 27 insertions, 20 deletions

diff --git a/src/mm-port-qmi.c b/src/mm-port-qmi.c
index 41f6033d..aec1c018 100644
--- a/src/mm-port-qmi.c
+++ b/src/mm-port-qmi.c
@@ -64,8 +64,9 @@ struct _MMPortQmiPrivate {
     QrtrNode  *node;
 #endif
 
-    /* timeout monitoring */
+    /* port monitoring */
     gulong timeout_monitoring_id;
+    gulong removed_monitoring_id;
     /* endpoint info */
     QmiDataEndpointType endpoint_type;
     gint                endpoint_interface_number;
@@ -131,16 +132,6 @@ mm_port_qmi_get_client (MMPortQmi  *self,
 
 /*****************************************************************************/
 
-QmiDevice *
-mm_port_qmi_peek_device (MMPortQmi *self)
-{
-    g_return_val_if_fail (MM_IS_PORT_QMI (self), NULL);
-
-    return self->priv->qmi_device;
-}
-
-/*****************************************************************************/
-
 static void
 initialize_endpoint_info (MMPortQmi *self)
 {
@@ -196,13 +187,17 @@ mm_port_qmi_get_endpoint_info (MMPortQmi *self, MMQmiDataEndpoint *out_endpoint)
 /*****************************************************************************/
 
 static void
-reset_timeout_monitoring (MMPortQmi *self,
-                          QmiDevice *qmi_device)
+reset_monitoring (MMPortQmi *self,
+                  QmiDevice *qmi_device)
 {
     if (self->priv->timeout_monitoring_id && qmi_device) {
         g_signal_handler_disconnect (qmi_device, self->priv->timeout_monitoring_id);
         self->priv->timeout_monitoring_id = 0;
     }
+    if (self->priv->removed_monitoring_id && qmi_device) {
+        g_signal_handler_disconnect (qmi_device, self->priv->removed_monitoring_id);
+        self->priv->removed_monitoring_id = 0;
+    }
 }
 
 static void
@@ -214,18 +209,30 @@ consecutive_timeouts_updated_cb (MMPortQmi  *self,
 }
 
 static void
-setup_timeout_monitoring (MMPortQmi *self,
-                          QmiDevice *qmi_device)
+device_removed_cb (MMPortQmi  *self)
+{
+    g_signal_emit_by_name (self, MM_PORT_SIGNAL_REMOVED);
+}
+
+static void
+setup_monitoring (MMPortQmi *self,
+                  QmiDevice *qmi_device)
 {
     g_assert (qmi_device);
 
-    reset_timeout_monitoring (self, qmi_device);
+    reset_monitoring (self, qmi_device);
 
     g_assert (!self->priv->timeout_monitoring_id);
     self->priv->timeout_monitoring_id = g_signal_connect_swapped (qmi_device,
                                                                   "notify::" QMI_DEVICE_CONSECUTIVE_TIMEOUTS,
                                                                   G_CALLBACK (consecutive_timeouts_updated_cb),
                                                                   self);
+
+    g_assert (!self->priv->removed_monitoring_id);
+    self->priv->removed_monitoring_id = g_signal_connect_swapped (qmi_device,
+                                                                  QMI_DEVICE_SIGNAL_REMOVED,
+                                                                  G_CALLBACK (device_removed_cb),
+                                                                  self);
 }
 
 /*****************************************************************************/
@@ -2532,7 +2539,7 @@ port_open_step (GTask *task)
         g_assert (ctx->device);
         g_assert (!self->priv->qmi_device);
         self->priv->qmi_device = g_object_ref (ctx->device);
-        setup_timeout_monitoring (self, ctx->device);
+        setup_monitoring (self, ctx->device);
         self->priv->in_progress = FALSE;
         g_task_return_boolean (task, TRUE);
         g_object_unref (task);
@@ -2672,8 +2679,8 @@ mm_port_qmi_close (MMPortQmi           *self,
     ctx->qmi_device = g_steal_pointer (&self->priv->qmi_device);
     g_task_set_task_data (task, ctx, (GDestroyNotify)port_qmi_close_context_free);
 
-    /* Reset timeout monitoring logic */
-    reset_timeout_monitoring (self, ctx->qmi_device);
+    /* Reset monitoring logic */
+    reset_monitoring (self, ctx->qmi_device);
 
     /* Release all allocated clients */
     for (l = self->priv->services; l; l = g_list_next (l)) {
@@ -2804,7 +2811,7 @@ dispose (GObject *object)
     g_clear_object (&self->priv->node);
 #endif
     /* Clear device object */
-    reset_timeout_monitoring (self, self->priv->qmi_device);
+    reset_monitoring (self, self->priv->qmi_device);
     g_clear_object (&self->priv->qmi_device);
 
     g_clear_pointer (&self->priv->net_driver, g_free);