device: Better define ownership passing for results

Some things were odd with regard to the ownership of passed objects. Try
to make things sane overall, in particular with the possible floating
FpPrint reference.

libfprint/fpi-device.c

@@ -908,7 +908,7 @@ fpi_device_enroll_complete (FpDevice *device, FpPrint *print, GError *error)
  * fpi_device_verify_complete:
  * @device: The #FpDevice
  * @result: The #FpiMatchResult of the operation
- * @print: The scanned #FpPrint
+ * @print: (transfer floating) The scanned #FpPrint
  * @error: A #GError if result is %FPI_MATCH_ERROR
  *
  * Finish an ongoing verify operation. The returned print should be
@@ -929,6 +929,9 @@ fpi_device_verify_complete (FpDevice      *device,
 
   clear_device_cancel_action (device);
 
+  if (print)
+    g_object_ref_sink (print);
+
   g_object_set_data_full (G_OBJECT (priv->current_task),
                           "print",
                           print,
@@ -963,8 +966,8 @@ fpi_device_verify_complete (FpDevice      *device,
 /**
  * fpi_device_identify_complete:
  * @device: The #FpDevice
- * @match: The matching #FpPrint from the passed gallery, or %NULL if none matched
+ * @match: (transfer none): The matching #FpPrint from the passed gallery, or %NULL if none matched
- * @print: The scanned #FpPrint, may be %NULL
+ * @print: (transfer floating): The scanned #FpPrint, may be %NULL
  * @error: The #GError or %NULL on success
  *
  * Finish an ongoing identify operation. The match that was identified is
@@ -986,6 +989,12 @@ fpi_device_identify_complete (FpDevice *device,
 
   clear_device_cancel_action (device);
 
+  if (match)
+    g_object_ref (match);
+
+  if (print)
+    g_object_ref_sink (print);
+
   g_object_set_data_full (G_OBJECT (priv->current_task),
                           "print",
                           print,
@@ -1134,7 +1143,7 @@ fpi_device_list_complete (FpDevice  *device,
  * fpi_device_enroll_progress:
  * @device: The #FpDevice
  * @completed_stages: The number of stages that are completed at this point
- * @print: (transfer full): The #FpPrint for the newly completed stage or %NULL on failure
+ * @print: (transfer floating): The #FpPrint for the newly completed stage or %NULL on failure
  * @error: (transfer full): The #GError or %NULL on success
  *
  * Notify about the progress of the enroll operation. This is important for UI interaction.
@@ -1155,6 +1164,9 @@ fpi_device_enroll_progress (FpDevice *device,
 
   g_debug ("Device reported enroll progress, reported %i of %i have been completed", completed_stages, priv->nr_enroll_stages);
 
+  if (print)
+    g_object_ref_sink (print);
+
   if (error && print)
     {
       g_warning ("Driver passed an error and also provided a print, returning error!");

libfprint/fpi-image-device.c

@@ -226,7 +226,7 @@ fpi_image_device_minutiae_detected (GObject *source_object, GAsyncResult *res, g
 
           if (fpi_print_bz3_match (template, print, priv->bz3_threshold, &error) == FPI_MATCH_SUCCESS)
             {
-              result = g_object_ref (template);
+              result = template;
               break;
             }
         }

tests/test-fpi-device.c

@@ -548,10 +548,10 @@ test_driver_verify (void)
 {
   g_autoptr(GError) error = NULL;
   g_autoptr(FpAutoCloseDevice) device = auto_close_fake_device_new ();
-  g_autoptr(FpPrint) enrolled_print = fp_print_new (device);
+  g_autoptr(FpPrint) enrolled_print = g_object_ref_sink (fp_print_new (device));
+  g_autoptr(FpPrint) out_print = NULL;
   FpDeviceClass *dev_class = FP_DEVICE_GET_CLASS (device);
   FpiDeviceFake *fake_dev = FPI_DEVICE_FAKE (device);
-  FpPrint *out_print = NULL;
   gboolean match;
 
   fake_dev->ret_result = FPI_MATCH_SUCCESS;
@@ -570,10 +570,10 @@ test_driver_verify_fail (void)
 {
   g_autoptr(GError) error = NULL;
   g_autoptr(FpAutoCloseDevice) device = auto_close_fake_device_new ();
-  g_autoptr(FpPrint) enrolled_print = fp_print_new (device);
+  g_autoptr(FpPrint) enrolled_print = g_object_ref_sink (fp_print_new (device));
+  g_autoptr(FpPrint) out_print = NULL;
   FpDeviceClass *dev_class = FP_DEVICE_GET_CLASS (device);
   FpiDeviceFake *fake_dev = FPI_DEVICE_FAKE (device);
-  FpPrint *out_print = NULL;
   gboolean match;
 
   fake_dev->ret_result = FPI_MATCH_FAIL;
@@ -591,10 +591,10 @@ test_driver_verify_error (void)
 {
   g_autoptr(GError) error = NULL;
   g_autoptr(FpAutoCloseDevice) device = auto_close_fake_device_new ();
-  g_autoptr(FpPrint) enrolled_print = fp_print_new (device);
+  g_autoptr(FpPrint) enrolled_print = g_object_ref_sink (fp_print_new (device));
+  g_autoptr(FpPrint) out_print = NULL;
   FpDeviceClass *dev_class = FP_DEVICE_GET_CLASS (device);
   FpiDeviceFake *fake_dev = FPI_DEVICE_FAKE (device);
-  FpPrint *out_print = NULL;
   gboolean match;
 
   fake_dev->ret_result = FPI_MATCH_ERROR;
@@ -641,16 +641,16 @@ test_driver_identify (void)
 {
   g_autoptr(GError) error = NULL;
   g_autoptr(FpPrint) print = NULL;
+  g_autoptr(FpPrint) matched_print = NULL;
   g_autoptr(FpAutoCloseDevice) device = auto_close_fake_device_new ();
   g_autoptr(GPtrArray) prints = g_ptr_array_new_with_free_func (g_object_unref);
   FpDeviceClass *dev_class = FP_DEVICE_GET_CLASS (device);
   FpiDeviceFake *fake_dev = FPI_DEVICE_FAKE (device);
-  FpPrint *matched_print;
   FpPrint *expected_matched;
   unsigned int i;
 
   for (i = 0; i < 500; ++i)
-    g_ptr_array_add (prints, fp_print_new (device));
+    g_ptr_array_add (prints, g_object_ref_sink (fp_print_new (device)));
 
   expected_matched = g_ptr_array_index (prints, g_random_int_range (0, 499));
   fp_print_set_description (expected_matched, "fake-verified");
@@ -673,15 +673,15 @@ test_driver_identify_fail (void)
 {
   g_autoptr(GError) error = NULL;
   g_autoptr(FpPrint) print = NULL;
+  g_autoptr(FpPrint) matched_print = NULL;
   g_autoptr(FpAutoCloseDevice) device = auto_close_fake_device_new ();
   g_autoptr(GPtrArray) prints = g_ptr_array_new_with_free_func (g_object_unref);
   FpDeviceClass *dev_class = FP_DEVICE_GET_CLASS (device);
   FpiDeviceFake *fake_dev = FPI_DEVICE_FAKE (device);
-  FpPrint *matched_print;
   unsigned int i;
 
   for (i = 0; i < 500; ++i)
-    g_ptr_array_add (prints, fp_print_new (device));
+    g_ptr_array_add (prints, g_object_ref_sink (fp_print_new (device)));
 
   g_assert_true (fp_device_supports_identify (device));
 
@@ -700,16 +700,16 @@ test_driver_identify_error (void)
 {
   g_autoptr(GError) error = NULL;
   g_autoptr(FpPrint) print = NULL;
+  g_autoptr(FpPrint) matched_print = NULL;
   g_autoptr(FpAutoCloseDevice) device = auto_close_fake_device_new ();
   g_autoptr(GPtrArray) prints = g_ptr_array_new_with_free_func (g_object_unref);
   FpDeviceClass *dev_class = FP_DEVICE_GET_CLASS (device);
   FpiDeviceFake *fake_dev = FPI_DEVICE_FAKE (device);
-  FpPrint *matched_print;
   FpPrint *expected_matched;
   unsigned int i;
 
   for (i = 0; i < 500; ++i)
-    g_ptr_array_add (prints, fp_print_new (device));
+    g_ptr_array_add (prints, g_object_ref_sink (fp_print_new (device)));
 
   expected_matched = g_ptr_array_index (prints, g_random_int_range (0, 499));
   fp_print_set_description (expected_matched, "fake-verified");