core: make sure objects retrieved with g_object_get() are valid in the ifaces

The interfaces usually retrieve objects (e.g. skeletons) from the Modem object
using g_object_get(), but we didn't make sure that these objects were actually
valid before using them.

This should clean up errors happening when the modem gets unplugged and still
some actions are ongoing.

Should fix https://bugzilla.gnome.org/show_bug.cgi?id=685933

1 files changed, 127 insertions, 117 deletions

diff --git a/src/mm-iface-modem-messaging.c b/src/mm-iface-modem-messaging.c
index d94f6c14..f7349681 100644
--- a/src/mm-iface-modem-messaging.c
+++ b/src/mm-iface-modem-messaging.c
@@ -205,7 +205,14 @@ handle_delete_auth_ready (MMBaseModem *self,
     g_object_get (self,
                   MM_IFACE_MODEM_MESSAGING_SMS_LIST, &list,
                   NULL);
-    g_assert (list != NULL);
+    if (!list) {
+        g_dbus_method_invocation_return_error (ctx->invocation,
+                                               MM_CORE_ERROR,
+                                               MM_CORE_ERROR_WRONG_STATE,
+                                               "Cannot delete SMS: missing SMS list");
+        handle_delete_context_free (ctx);
+        return;
+    }
 
     mm_sms_list_delete_sms (list,
                             ctx->path,
@@ -297,6 +304,7 @@ handle_create_auth_ready (MMBaseModem *self,
                                       properties,
                                       &error);
     if (!sms) {
+        g_object_unref (properties);
         g_dbus_method_invocation_take_error (ctx->invocation, error);
         handle_create_context_free (ctx);
         return;
@@ -305,7 +313,16 @@ handle_create_auth_ready (MMBaseModem *self,
     g_object_get (self,
                   MM_IFACE_MODEM_MESSAGING_SMS_LIST, &list,
                   NULL);
-    g_assert (list != NULL);
+    if (!list) {
+        g_object_unref (properties);
+        g_object_unref (sms);
+        g_dbus_method_invocation_return_error (ctx->invocation,
+                                               MM_CORE_ERROR,
+                                               MM_CORE_ERROR_WRONG_STATE,
+                                               "Cannot create SMS: missing SMS list");
+        handle_create_context_free (ctx);
+        return;
+    }
 
     /* Add it to the list */
     mm_sms_list_add_sms (list, sms);
@@ -372,7 +389,13 @@ handle_list (MmGdbusModemMessaging *skeleton,
     g_object_get (self,
                   MM_IFACE_MODEM_MESSAGING_SMS_LIST, &list,
                   NULL);
-    g_assert (list != NULL);
+    if (!list) {
+        g_dbus_method_invocation_return_error (invocation,
+                                               MM_CORE_ERROR,
+                                               MM_CORE_ERROR_WRONG_STATE,
+                                               "Cannot list SMS: missing SMS list");
+        return TRUE;
+    }
 
     paths = mm_sms_list_get_paths (list);
     mm_gdbus_modem_messaging_complete_list (skeleton,
@@ -398,7 +421,9 @@ mm_iface_modem_messaging_take_part (MMIfaceModemMessaging *self,
     g_object_get (self,
                   MM_IFACE_MODEM_MESSAGING_SMS_LIST, &list,
                   NULL);
-    g_assert (list != NULL);
+    if (!list)
+        return FALSE;
+
     added = mm_sms_list_take_part (list, sms_part, state, storage, &error);
     if (!added) {
         mm_dbg ("Couldn't take part in SMS list: '%s'", error->message);
@@ -504,35 +529,14 @@ struct _DisablingContext {
     MmGdbusModemMessaging *skeleton;
 };
 
-static DisablingContext *
-disabling_context_new (MMIfaceModemMessaging *self,
-                       GAsyncReadyCallback callback,
-                       gpointer user_data)
-{
-    DisablingContext *ctx;
-
-    ctx = g_new0 (DisablingContext, 1);
-    ctx->self = g_object_ref (self);
-    ctx->result = g_simple_async_result_new (G_OBJECT (self),
-                                             callback,
-                                             user_data,
-                                             disabling_context_new);
-    ctx->step = DISABLING_STEP_FIRST;
-    g_object_get (ctx->self,
-                  MM_IFACE_MODEM_MESSAGING_DBUS_SKELETON, &ctx->skeleton,
-                  NULL);
-    g_assert (ctx->skeleton != NULL);
-
-    return ctx;
-}
-
 static void
 disabling_context_complete_and_free (DisablingContext *ctx)
 {
     g_simple_async_result_complete_in_idle (ctx->result);
     g_object_unref (ctx->self);
     g_object_unref (ctx->result);
-    g_object_unref (ctx->skeleton);
+    if (ctx->skeleton)
+        g_object_unref (ctx->skeleton);
     g_free (ctx);
 }
 
@@ -633,12 +637,31 @@ interface_disabling_step (DisablingContext *ctx)
 
 void
 mm_iface_modem_messaging_disable (MMIfaceModemMessaging *self,
-                                 GAsyncReadyCallback callback,
-                                 gpointer user_data)
+                                  GAsyncReadyCallback callback,
+                                  gpointer user_data)
 {
-    interface_disabling_step (disabling_context_new (self,
-                                                     callback,
-                                                     user_data));
+    DisablingContext *ctx;
+
+    ctx = g_new0 (DisablingContext, 1);
+    ctx->self = g_object_ref (self);
+    ctx->result = g_simple_async_result_new (G_OBJECT (self),
+                                             callback,
+                                             user_data,
+                                             mm_iface_modem_messaging_disable);
+    ctx->step = DISABLING_STEP_FIRST;
+    g_object_get (ctx->self,
+                  MM_IFACE_MODEM_MESSAGING_DBUS_SKELETON, &ctx->skeleton,
+                  NULL);
+    if (!ctx->skeleton) {
+        g_simple_async_result_set_error (ctx->result,
+                                         MM_CORE_ERROR,
+                                         MM_CORE_ERROR_FAILED,
+                                         "Couldn't get interface skeleton");
+        disabling_context_complete_and_free (ctx);
+        return;
+    }
+
+    interface_disabling_step (ctx);
 }
 
 /*****************************************************************************/
@@ -665,30 +688,6 @@ struct _EnablingContext {
     guint mem1_storage_index;
 };
 
-static EnablingContext *
-enabling_context_new (MMIfaceModemMessaging *self,
-                      GCancellable *cancellable,
-                      GAsyncReadyCallback callback,
-                      gpointer user_data)
-{
-    EnablingContext *ctx;
-
-    ctx = g_new0 (EnablingContext, 1);
-    ctx->self = g_object_ref (self);
-    ctx->cancellable = g_object_ref (cancellable);
-    ctx->result = g_simple_async_result_new (G_OBJECT (self),
-                                             callback,
-                                             user_data,
-                                             enabling_context_new);
-    ctx->step = ENABLING_STEP_FIRST;
-    g_object_get (ctx->self,
-                  MM_IFACE_MODEM_MESSAGING_DBUS_SKELETON, &ctx->skeleton,
-                  NULL);
-    g_assert (ctx->skeleton != NULL);
-
-    return ctx;
-}
-
 static void
 enabling_context_complete_and_free (EnablingContext *ctx)
 {
@@ -696,7 +695,8 @@ enabling_context_complete_and_free (EnablingContext *ctx)
     g_object_unref (ctx->self);
     g_object_unref (ctx->result);
     g_object_unref (ctx->cancellable);
-    g_object_unref (ctx->skeleton);
+    if (ctx->skeleton)
+        g_object_unref (ctx->skeleton);
     g_free (ctx);
 }
 
@@ -722,28 +722,24 @@ mm_iface_modem_messaging_enable_finish (MMIfaceModemMessaging *self,
     return !g_simple_async_result_propagate_error (G_SIMPLE_ASYNC_RESULT (res), error);
 }
 
-#undef VOID_REPLY_READY_FN
-#define VOID_REPLY_READY_FN(NAME)                                       \
-    static void                                                         \
-    NAME##_ready (MMIfaceModemMessaging *self,                          \
-                  GAsyncResult *res,                                    \
-                  EnablingContext *ctx)                                 \
-    {                                                                   \
-        GError *error = NULL;                                           \
-                                                                        \
-        MM_IFACE_MODEM_MESSAGING_GET_INTERFACE (self)->NAME##_finish (self, res, &error); \
-        if (error) {                                                    \
-            g_simple_async_result_take_error (ctx->result, error);      \
-            enabling_context_complete_and_free (ctx);                   \
-            return;                                                     \
-        }                                                               \
-                                                                        \
-        /* Go on to next step */                                        \
-        ctx->step++;                                                    \
-        interface_enabling_step (ctx);                                  \
+static void
+setup_sms_format_ready (MMIfaceModemMessaging *self,
+                        GAsyncResult *res,
+                        EnablingContext *ctx)
+{
+    GError *error = NULL;
+
+    MM_IFACE_MODEM_MESSAGING_GET_INTERFACE (self)->setup_sms_format_finish (self, res, &error);
+    if (error) {
+        g_simple_async_result_take_error (ctx->result, error);
+        enabling_context_complete_and_free (ctx);
+        return;
     }
 
-VOID_REPLY_READY_FN (setup_sms_format)
+    /* Go on to next step */
+    ctx->step++;
+    interface_enabling_step (ctx);
+}
 
 static void load_initial_sms_parts_from_storages (EnablingContext *ctx);
 
@@ -820,7 +816,24 @@ load_initial_sms_parts_from_storages (EnablingContext *ctx)
     return;
 }
 
-VOID_REPLY_READY_FN (setup_unsolicited_events)
+static void
+setup_unsolicited_events_ready (MMIfaceModemMessaging *self,
+                                GAsyncResult *res,
+                                EnablingContext *ctx)
+{
+    GError *error = NULL;
+
+    MM_IFACE_MODEM_MESSAGING_GET_INTERFACE (self)->setup_unsolicited_events_finish (self, res, &error);
+    if (error) {
+        g_simple_async_result_take_error (ctx->result, error);
+        enabling_context_complete_and_free (ctx);
+        return;
+    }
+
+    /* Go on to next step */
+    ctx->step++;
+    interface_enabling_step (ctx);
+}
 
 static void
 enable_unsolicited_events_ready (MMIfaceModemMessaging *self,
@@ -989,10 +1002,29 @@ mm_iface_modem_messaging_enable (MMIfaceModemMessaging *self,
                                  GAsyncReadyCallback callback,
                                  gpointer user_data)
 {
-    interface_enabling_step (enabling_context_new (self,
-                                                   cancellable,
-                                                   callback,
-                                                   user_data));
+    EnablingContext *ctx;
+
+    ctx = g_new0 (EnablingContext, 1);
+    ctx->self = g_object_ref (self);
+    ctx->cancellable = g_object_ref (cancellable);
+    ctx->result = g_simple_async_result_new (G_OBJECT (self),
+                                             callback,
+                                             user_data,
+                                             mm_iface_modem_messaging_enable);
+    ctx->step = ENABLING_STEP_FIRST;
+    g_object_get (ctx->self,
+                  MM_IFACE_MODEM_MESSAGING_DBUS_SKELETON, &ctx->skeleton,
+                  NULL);
+    if (!ctx->skeleton) {
+        g_simple_async_result_set_error (ctx->result,
+                                         MM_CORE_ERROR,
+                                         MM_CORE_ERROR_FAILED,
+                                         "Couldn't get interface skeleton");
+        enabling_context_complete_and_free (ctx);
+        return;
+    }
+
+    interface_enabling_step (ctx);
 }
 
 /*****************************************************************************/
@@ -1016,29 +1048,6 @@ struct _InitializationContext {
     InitializationStep step;
 };
 
-static InitializationContext *
-initialization_context_new (MMIfaceModemMessaging *self,
-                            GCancellable *cancellable,
-                            GAsyncReadyCallback callback,
-                            gpointer user_data)
-{
-    InitializationContext *ctx;
-
-    ctx = g_new0 (InitializationContext, 1);
-    ctx->self = g_object_ref (self);
-    ctx->cancellable = g_object_ref (cancellable);
-    ctx->result = g_simple_async_result_new (G_OBJECT (self),
-                                             callback,
-                                             user_data,
-                                             initialization_context_new);
-    ctx->step = INITIALIZATION_STEP_FIRST;
-    g_object_get (ctx->self,
-                  MM_IFACE_MODEM_MESSAGING_DBUS_SKELETON, &ctx->skeleton,
-                  NULL);
-    g_assert (ctx->skeleton != NULL);
-    return ctx;
-}
-
 static void
 initialization_context_complete_and_free (InitializationContext *ctx)
 {
@@ -1269,9 +1278,6 @@ mm_iface_modem_messaging_initialize_finish (MMIfaceModemMessaging *self,
                                             GAsyncResult *res,
                                             GError **error)
 {
-    g_return_val_if_fail (MM_IS_IFACE_MODEM_MESSAGING (self), FALSE);
-    g_return_val_if_fail (G_IS_ASYNC_RESULT (res), FALSE);
-
     return !g_simple_async_result_propagate_error (G_SIMPLE_ASYNC_RESULT (res), error);
 }
 
@@ -1281,10 +1287,9 @@ mm_iface_modem_messaging_initialize (MMIfaceModemMessaging *self,
                                      GAsyncReadyCallback callback,
                                      gpointer user_data)
 {
+    InitializationContext *ctx;
     MmGdbusModemMessaging *skeleton = NULL;
 
-    g_return_if_fail (MM_IS_IFACE_MODEM_MESSAGING (self));
-
     /* Did we already create it? */
     g_object_get (self,
                   MM_IFACE_MODEM_MESSAGING_DBUS_SKELETON, &skeleton,
@@ -1304,18 +1309,23 @@ mm_iface_modem_messaging_initialize (MMIfaceModemMessaging *self,
     }
 
     /* Perform async initialization here */
-    interface_initialization_step (initialization_context_new (self,
-                                                               cancellable,
-                                                               callback,
-                                                               user_data));
-    g_object_unref (skeleton);
+
+    ctx = g_new0 (InitializationContext, 1);
+    ctx->self = g_object_ref (self);
+    ctx->cancellable = g_object_ref (cancellable);
+    ctx->result = g_simple_async_result_new (G_OBJECT (self),
+                                             callback,
+                                             user_data,
+                                             mm_iface_modem_messaging_initialize);
+    ctx->step = INITIALIZATION_STEP_FIRST;
+    ctx->skeleton = skeleton;
+
+    interface_initialization_step (ctx);
 }
 
 void
 mm_iface_modem_messaging_shutdown (MMIfaceModemMessaging *self)
 {
-    g_return_if_fail (MM_IS_IFACE_MODEM_MESSAGING (self));
-
     /* Unexport DBus interface and remove the skeleton */
     mm_gdbus_object_skeleton_set_modem_messaging (MM_GDBUS_OBJECT_SKELETON (self), NULL);
     g_object_set (self,