tod: Add wrapper for goodix-tod not handling identification with no prints

Newer fprintd supports duplicate-detection, this implies sending to the
device an empty prints gallery, expecting the device to give us a
matched print against its storage.

In case the device has no storage we're doing this anyway, but goodix
doesn't handle this properly, so let's just ignore the case if no prints
are passed.

libfprint/tod/meson.build

@@ -19,6 +19,7 @@ mapfile = configure_file(input: 'libfprint-tod.ver.in',
 libfprint_tod_private = static_library('fprint-tod-private',
     sources: [
         'tod-shared-loader.c',
+        'tod-goodix-wrapper.c',
     ],
     include_directories: include_directories('..'),
     link_with: libfprint_private,

libfprint/tod/tod-goodix-wrapper.c

@@ -0,0 +1,56 @@
+/*
+ * Shared library loader for libfprint
+ * Copyright (C) 2022 Marco Trevisan <marco.trevisan@canonical.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "fp-device-private.h"
+#include "fpi-device.h"
+#define FP_COMPONENT "tod"
+
+#include "tod-goodix-wrapper.h"
+
+static void (*goodix_moc_identify) (FpDevice *) = NULL;
+
+static void
+goodix_tod_identify_wrapper (FpDevice *device)
+{
+  GPtrArray *prints;
+
+  fpi_device_get_identify_data (device, &prints);
+
+  if (prints->len)
+    return goodix_moc_identify (device);
+
+  g_warning ("%s does not support identify with empty gallery, let's skip it",
+             fp_device_get_name (device));
+
+  fpi_device_identify_report (device, NULL, NULL, NULL);
+  fpi_device_identify_complete (device, NULL);
+}
+
+void
+goodix_tod_wrapper_init (FpDeviceClass *device_class)
+{
+  g_assert (g_strcmp0 (device_class->id, "goodix-tod") == 0);
+  g_assert (goodix_moc_identify == NULL);
+
+  g_message ("Creating TOD wrapper for %s (%s) driver",
+             device_class->id, device_class->full_name);
+
+  goodix_moc_identify = device_class->identify;
+  device_class->identify = goodix_tod_identify_wrapper;
+}

libfprint/tod/tod-goodix-wrapper.h

@@ -0,0 +1,24 @@
+/*
+ * Shared library loader for libfprint
+ * Copyright (C) 2022 Marco Trevisan <marco.trevisan@canonical.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#pragma once
+
+#include "drivers_api.h"
+
+void goodix_tod_wrapper_init (FpDeviceClass *device_class);

libfprint/tod/tod-shared-loader.c

@@ -22,6 +22,7 @@
 #include <gmodule.h>
 
 #include "tod-shared-loader.h"
+#include "tod-goodix-wrapper.h"
 #include "fpi-device.h"
 #include "fpi-log.h"
 #include "tod-config.h"
@@ -131,6 +132,9 @@ fpi_tod_shared_drivers_register (void)
         {
           g_debug ("Initializing features for driver %s", cls->id);
           fpi_device_class_auto_initialize_features (cls);
+
+          if (g_strcmp0 (cls->id, "goodix-tod") == 0)
+            goodix_tod_wrapper_init (cls);
         }
 
       shared_modules = g_list_prepend (shared_modules,