lib: Major rewrite of the libfprint core and API

This is a rewrite of the core based on GObject and Gio. This commit breaks the build in a lot of ways, but basic functionality will start working again with the next commits.
2025-11-15 07:38:12 +00:00 · 2019-07-03 23:29:05 +02:00
parent 30a449841c
commit 689aff0232
53 changed files with 8358 additions and 6759 deletions
--- a/libfprint/fp-image-device.c
+++ b/libfprint/fp-image-device.c
@@ -0,0 +1,795 @@
+/*
+ * FpImageDevice - An image based fingerprint reader device
+ * Copyright (C) 2019 Benjamin Berg <bberg@redhat.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
+ */
+
+#define FP_COMPONENT "image_device"
+#include "fpi-log.h"
+
+#include "fpi-image-device.h"
+#include "fpi-print.h"
+#include "fpi-image.h"
+
+#define MIN_ACCEPTABLE_MINUTIAE 10
+#define BOZORTH3_DEFAULT_THRESHOLD 40
+#define IMG_ENROLL_STAGES 5
+
+/**
+ * SECTION: fp-image-device
+ * @title: FpImageDevice
+ * @short_description: Image device subclass
+ *
+ * This is a helper class for the commonly found image based devices.
+ */
+
+/**
+ * SECTION: fpi-image-device
+ * @title: Internal FpImageDevice
+ * @short_description: Internal image device routines
+ *
+ * See #FpImageDeviceClass for more details. Also see the public
+ * #FpImageDevice routines.
+ */
+
+typedef struct
+{
+  FpImageDeviceState state;
+  gboolean           active;
+
+  gint               enroll_stage;
+
+  guint              pending_activation_timeout_id;
+  gboolean           pending_activation_timeout_waiting_finger_off;
+
+  gint               bz3_threshold;
+} FpImageDevicePrivate;
+
+G_DEFINE_ABSTRACT_TYPE_WITH_PRIVATE (FpImageDevice, fp_image_device, FP_TYPE_DEVICE)
+
+
+/*******************************************************/
+
+/* TODO:
+ * - sanitize_image seems a bit odd, in particular the sizing stuff.
+ **/
+
+/* Static helper functions */
+
+static void
+fp_image_device_change_state (FpImageDevice *self, FpImageDeviceState state)
+{
+  FpImageDevicePrivate *priv = fp_image_device_get_instance_private (self);
+  FpImageDeviceClass *cls = FP_IMAGE_DEVICE_GET_CLASS (self);
+
+  /* Cannot change to inactive using this function. */
+  g_assert (state != FP_IMAGE_DEVICE_STATE_INACTIVE);
+
+  /* We might have been waiting for the finger to go OFF to start the
+   * next operation. */
+  if (priv->pending_activation_timeout_id)
+    {
+      g_source_remove (priv->pending_activation_timeout_id);
+      priv->pending_activation_timeout_id = 0;
+    }
+
+  fp_dbg ("Image device internal state change from %d to %d\n", priv->state, state);
+
+  priv->state = state;
+
+  /* change_state is the only callback which is optional and does not
+   * have a default implementation. */
+  if (cls->change_state)
+    cls->change_state (self, state);
+}
+
+static void
+fp_image_device_activate (FpImageDevice *self)
+{
+  FpImageDevicePrivate *priv = fp_image_device_get_instance_private (self);
+  FpImageDeviceClass *cls = FP_IMAGE_DEVICE_GET_CLASS (self);
+
+  g_assert (!priv->active);
+
+  /* We don't have a neutral ACTIVE state, but we always will
+   * go into WAIT_FINGER_ON afterwards. */
+  priv->state = FP_IMAGE_DEVICE_STATE_AWAIT_FINGER_ON;
+
+  /* We might have been waiting for deactivation to finish before
+   * starting the next operation. */
+  if (priv->pending_activation_timeout_id)
+    {
+      g_source_remove (priv->pending_activation_timeout_id);
+      priv->pending_activation_timeout_id = 0;
+    }
+
+  fp_dbg ("Activating image device\n");
+  cls->activate (self);
+}
+
+static void
+fp_image_device_deactivate (FpDevice *device)
+{
+  FpImageDevice *self = FP_IMAGE_DEVICE (device);
+  FpImageDevicePrivate *priv = fp_image_device_get_instance_private (self);
+  FpImageDeviceClass *cls = FP_IMAGE_DEVICE_GET_CLASS (device);
+
+  if (!priv->active)
+    {
+      /* XXX: We currently deactivate both from minutiae scan result
+       *      and finger off report. */
+      fp_dbg ("Already deactivated, ignoring request.");
+      return;
+    }
+  priv->state = FP_IMAGE_DEVICE_STATE_INACTIVE;
+
+  fp_dbg ("Deactivating image device\n");
+  cls->deactivate (self);
+}
+
+static gboolean
+pending_activation_timeout (gpointer user_data)
+{
+  FpImageDevice *self = FP_IMAGE_DEVICE (user_data);
+  FpImageDevicePrivate *priv = fp_image_device_get_instance_private (self);
+
+  priv->pending_activation_timeout_id = 0;
+
+  if (priv->pending_activation_timeout_waiting_finger_off)
+    fpi_device_action_error (FP_DEVICE (self),
+                             fpi_device_retry_new_msg (FP_DEVICE_RETRY_REMOVE_FINGER,
+                                                       "Remove finger before requesting another scan operation"));
+  else
+    fpi_device_action_error (FP_DEVICE (self),
+                             fpi_device_retry_new (FP_DEVICE_RETRY_GENERAL));
+
+  return G_SOURCE_REMOVE;
+}
+
+/* Callbacks/vfuncs */
+static void
+fp_image_device_open (FpDevice *device)
+{
+  FpImageDeviceClass *cls = FP_IMAGE_DEVICE_GET_CLASS (device);
+
+  /* Nothing special about opening an image device, just
+   * forward the request. */
+  cls->img_open (FP_IMAGE_DEVICE (device));
+}
+
+static void
+fp_image_device_close (FpDevice *device)
+{
+  FpImageDevice *self = FP_IMAGE_DEVICE (device);
+  FpImageDeviceClass *cls = FP_IMAGE_DEVICE_GET_CLASS (self);
+  FpImageDevicePrivate *priv = fp_image_device_get_instance_private (self);
+
+  /* In the close case we may need to wait/force deactivation first.
+   * Three possible cases:
+   *  1. We are inactive
+   *     -> immediately close
+   *  2. We are waiting for finger off
+   *     -> imediately deactivate
+   *  3. We are deactivating
+   *     -> handled by deactivate_complete */
+
+  if (!priv->active)
+    cls->img_close (self);
+  else if (priv->state != FP_IMAGE_DEVICE_STATE_INACTIVE)
+    fp_image_device_deactivate (device);
+}
+
+static void
+fp_image_device_cancel_action (FpDevice *device)
+{
+  FpImageDevice *self = FP_IMAGE_DEVICE (device);
+  FpDeviceAction action;
+
+  action = fpi_device_get_current_action (device);
+
+  /* We can only cancel capture operations, in that case, deactivate and return
+   * an error immediately. */
+  if (action == FP_DEVICE_ACTION_ENROLL ||
+      action == FP_DEVICE_ACTION_VERIFY ||
+      action == FP_DEVICE_ACTION_IDENTIFY ||
+      action == FP_DEVICE_ACTION_CAPTURE)
+    {
+      fp_image_device_deactivate (FP_DEVICE (self));
+
+      /* XXX: Some nicer way of doing this would be good. */
+      fpi_device_action_error (FP_DEVICE (self),
+                               g_error_new (G_IO_ERROR,
+                                            G_IO_ERROR_CANCELLED,
+                                            "Device operation was cancelled"));
+    }
+}
+
+static void
+fp_image_device_start_capture_action (FpDevice *device)
+{
+  FpImageDevice *self = FP_IMAGE_DEVICE (device);
+  FpImageDevicePrivate *priv = fp_image_device_get_instance_private (self);
+  FpDeviceAction action;
+
+  /* There is just one action that we cannot support out
+   * of the box, which is a capture without first waiting
+   * for a finger to be on the device.
+   */
+  action = fpi_device_get_current_action (device);
+  if (action == FP_DEVICE_ACTION_CAPTURE)
+    {
+      gboolean wait_for_finger;
+
+      fpi_device_get_capture_data (device, &wait_for_finger);
+
+      if (!wait_for_finger)
+        {
+          fpi_device_action_error (device, fpi_device_error_new (FP_DEVICE_ERROR_NOT_SUPPORTED));
+          return;
+        }
+    }
+  else if (action == FP_DEVICE_ACTION_ENROLL)
+    {
+      FpPrint *enroll_print = NULL;
+
+      fpi_device_get_enroll_data (device, &enroll_print);
+      fpi_print_set_type (enroll_print, FP_PRINT_NBIS);
+    }
+
+  priv->enroll_stage = 0;
+
+  /* The device might still be deactivating from a previous call.
+   * In that situation, try to wait for a bit before reporting back an
+   * error (which will usually say that the user should remove the
+   * finger).
+   */
+  if (priv->state != FP_IMAGE_DEVICE_STATE_INACTIVE || priv->active)
+    {
+      g_debug ("Got a new request while the device was still active");
+      g_assert (priv->pending_activation_timeout_id == 0);
+      priv->pending_activation_timeout_id =
+        g_timeout_add (100, pending_activation_timeout, device);
+
+      if (priv->state == FP_IMAGE_DEVICE_STATE_AWAIT_FINGER_OFF)
+        priv->pending_activation_timeout_waiting_finger_off = TRUE;
+      else
+        priv->pending_activation_timeout_waiting_finger_off = FALSE;
+
+      return;
+    }
+
+  /* And activate the device; we rely on fpi_image_device_activate_complete()
+   * to be called when done (or immediately). */
+  fp_image_device_activate (self);
+}
+
+
+/*********************************************************/
+
+static void
+fp_image_device_finalize (GObject *object)
+{
+  FpImageDevice *self = (FpImageDevice *) object;
+  FpImageDevicePrivate *priv = fp_image_device_get_instance_private (self);
+
+  g_assert (priv->active == FALSE);
+
+  G_OBJECT_CLASS (fp_image_device_parent_class)->finalize (object);
+}
+
+static void
+fp_image_device_default_activate (FpImageDevice *self)
+{
+  fpi_image_device_activate_complete (self, NULL);
+}
+
+static void
+fp_image_device_default_deactivate (FpImageDevice *self)
+{
+  fpi_image_device_deactivate_complete (self, NULL);
+}
+
+static void
+fp_image_device_class_init (FpImageDeviceClass *klass)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (klass);
+  FpDeviceClass *fp_device_class = FP_DEVICE_CLASS (klass);
+
+  object_class->finalize = fp_image_device_finalize;
+
+  fp_device_class->open = fp_image_device_open;
+  fp_device_class->close = fp_image_device_close;
+  fp_device_class->enroll = fp_image_device_start_capture_action;
+  fp_device_class->verify = fp_image_device_start_capture_action;
+  fp_device_class->identify = fp_image_device_start_capture_action;
+  fp_device_class->capture = fp_image_device_start_capture_action;
+
+  fp_device_class->cancel = fp_image_device_cancel_action;
+
+  /* Default implementations */
+  klass->activate = fp_image_device_default_activate;
+  klass->deactivate = fp_image_device_default_deactivate;
+}
+
+static void
+fp_image_device_init (FpImageDevice *self)
+{
+  FpImageDevicePrivate *priv = fp_image_device_get_instance_private (self);
+  FpImageDeviceClass *cls = FP_IMAGE_DEVICE_GET_CLASS (self);
+
+  /* Set default values. */
+  fpi_device_set_nr_enroll_stages (FP_DEVICE (self), IMG_ENROLL_STAGES);
+
+  priv->bz3_threshold = BOZORTH3_DEFAULT_THRESHOLD;
+  if (cls->bz3_threshold > 0)
+    priv->bz3_threshold = cls->bz3_threshold;
+
+}
+
+static void
+fpi_image_device_minutiae_detected (GObject *source_object, GAsyncResult *res, gpointer user_data)
+{
+  g_autoptr(FpImage) image = FP_IMAGE (source_object);
+  GError *error = NULL;
+  FpPrint *print = NULL;
+  FpDevice *device = FP_DEVICE (user_data);
+  FpImageDevicePrivate *priv;
+  FpDeviceAction action;
+
+  /* Note: We rely on the device to not disappear during an operation. */
+
+  if (!fp_image_detect_minutiae_finish (image, res, &error))
+    {
+      /* Cancel operation . */
+      if (g_error_matches (error, G_IO_ERROR, G_IO_ERROR_CANCELLED))
+        {
+          fpi_device_action_error (device, g_steal_pointer (&error));
+          fp_image_device_deactivate (device);
+          return;
+        }
+
+      /* Replace error with a retry condition. */
+      g_warning ("Failed to detect minutiae: %s", error->message);
+      g_clear_pointer (&error, g_error_free);
+
+      error = fpi_device_retry_new_msg (FP_DEVICE_RETRY_GENERAL, "Minutiae detection failed, please retry");
+    }
+
+  priv = fp_image_device_get_instance_private (FP_IMAGE_DEVICE (device));
+  action = fpi_device_get_current_action (device);
+
+  if (action == FP_DEVICE_ACTION_CAPTURE)
+    {
+      fpi_device_capture_complete (device, g_steal_pointer (&image), error);
+      fp_image_device_deactivate (device);
+      return;
+    }
+
+  if (!error)
+    {
+      print = fp_print_new (device);
+      fpi_print_set_type (print, FP_PRINT_NBIS);
+      if (!fpi_print_add_from_image (print, image, &error))
+        g_clear_object (&print);
+    }
+
+  if (action == FP_DEVICE_ACTION_ENROLL)
+    {
+      FpPrint *enroll_print;
+      fpi_device_get_enroll_data (device, &enroll_print);
+
+      if (print)
+        {
+          fpi_print_add_print (enroll_print, print);
+          priv->enroll_stage += 1;
+        }
+
+      fpi_device_enroll_progress (device, priv->enroll_stage, print, error);
+
+      if (priv->enroll_stage == IMG_ENROLL_STAGES)
+        {
+          fpi_device_enroll_complete (device, g_object_ref (enroll_print), NULL);
+          fp_image_device_deactivate (device);
+        }
+    }
+  else if (action == FP_DEVICE_ACTION_VERIFY)
+    {
+      FpPrint *template;
+      FpiMatchResult result;
+
+      fpi_device_get_verify_data (device, &template);
+      if (print)
+        result = fpi_print_bz3_match (template, print, priv->bz3_threshold, &error);
+      else
+        result = FPI_MATCH_ERROR;
+
+      fpi_device_verify_complete (device, result, print, error);
+      fp_image_device_deactivate (device);
+    }
+  else if (action == FP_DEVICE_ACTION_IDENTIFY)
+    {
+      gint i;
+      GPtrArray *templates;
+      FpPrint *result = NULL;
+
+      fpi_device_get_identify_data (device, &templates);
+      for (i = 0; !error && i < templates->len; i++)
+        {
+          FpPrint *template = g_ptr_array_index (templates, i);
+
+          if (fpi_print_bz3_match (template, print, priv->bz3_threshold, &error) == FPI_MATCH_SUCCESS)
+            {
+              result = g_object_ref (template);
+              break;
+            }
+        }
+
+      fpi_device_identify_complete (device, result, print, error);
+      fp_image_device_deactivate (device);
+    }
+  else
+    {
+      /* XXX: This can be hit currently due to a race condition in the enroll code!
+       *      In that case we scan a further image even though the minutiae for the previous
+       *      one have not yet been detected.
+       *      We need to keep track on the pending minutiae detection and the fact that
+       *      it will finish eventually (or we may need to retry on error and activate the
+       *      device again). */
+      g_assert_not_reached ();
+    }
+}
+
+/*********************************************************/
+/* Private API */
+
+/**
+ * fpi_image_device_set_bz3_threshold:
+ * @self: a #FpImageDevice imaging fingerprint device
+ * @bz3_threshold: BZ3 threshold to use
+ *
+ * Dynamically adjust the bz3 threshold. This is only needed for drivers
+ * that support devices with different properties. It should generally be
+ * called from the probe callback, but is acceptable to call from the open
+ * callback.
+ */
+void
+fpi_image_device_set_bz3_threshold (FpImageDevice *self,
+                                    gint           bz3_threshold)
+{
+  FpImageDevicePrivate *priv = fp_image_device_get_instance_private (self);
+
+  g_return_if_fail (FP_IS_IMAGE_DEVICE (self));
+  g_return_if_fail (bz3_threshold > 0);
+
+  priv->bz3_threshold = bz3_threshold;
+}
+
+/**
+ * fpi_image_device_report_finger_status:
+ * @self: a #FpImageDevice imaging fingerprint device
+ * @present: whether the finger is present on the sensor
+ *
+ * Reports from the driver whether the user's finger is on
+ * the sensor.
+ */
+void
+fpi_image_device_report_finger_status (FpImageDevice *self,
+                                       gboolean       present)
+{
+  FpDevice *device = FP_DEVICE (self);
+  FpImageDevicePrivate *priv = fp_image_device_get_instance_private (self);
+  FpDeviceAction action;
+
+  action = fpi_device_get_current_action (device);
+
+  if (priv->state == FP_IMAGE_DEVICE_STATE_INACTIVE)
+    {
+      /* Do we really want to always ignore such reports? We could
+       * also track the state in case the user had the finger on
+       * the device at initialisation time and the driver reports
+       * this early.
+       */
+      g_debug ("Ignoring finger presence report as the device is not active!");
+      return;
+    }
+
+  action = fpi_device_get_current_action (device);
+
+  g_assert (action != FP_DEVICE_ACTION_OPEN);
+  g_assert (action != FP_DEVICE_ACTION_CLOSE);
+
+  g_debug ("Image device reported finger status: %s", present ? "on" : "off");
+
+  if (present && priv->state == FP_IMAGE_DEVICE_STATE_AWAIT_FINGER_ON)
+    {
+      fp_image_device_change_state (self, FP_IMAGE_DEVICE_STATE_CAPTURE);
+    }
+  else if (!present && priv->state == FP_IMAGE_DEVICE_STATE_AWAIT_FINGER_OFF)
+    {
+      /* We need to deactivate or continue to await finger */
+
+      /* There are three possible situations:
+       *  1. We are deactivating the device and the action is still in progress
+       *     (minutiae detection).
+       *  2. We are still deactivating the device after an action completed
+       *  3. We were waiting for finger removal to start the new action
+       * Either way, we always end up deactivating except for the enroll case.
+       * XXX: This is not quite correct though, as we assume we need another finger
+       *      scan even though we might be processing the last one (successfully).
+       */
+      if (action != FP_DEVICE_ACTION_ENROLL)
+        fp_image_device_deactivate (device);
+      else
+        fp_image_device_change_state (self, FP_IMAGE_DEVICE_STATE_AWAIT_FINGER_ON);
+    }
+}
+
+/**
+ * fpi_image_device_image_captured:
+ * @self: a #FpImageDevice imaging fingerprint device
+ * @image: whether the finger is present on the sensor
+ *
+ * Reports an image capture. Only use this function if the image was
+ * captured successfully. If there was an issue where the user should
+ * retry, use fpi_image_device_retry_scan() to report the retry condition.
+ *
+ * In the event of a fatal error for the operation use
+ * fpi_image_device_session_error(). This will abort the entire operation
+ * including e.g. an enroll operation which captures multiple images during
+ * one session.
+ */
+void
+fpi_image_device_image_captured (FpImageDevice *self, FpImage *image)
+{
+  FpImageDevicePrivate *priv = fp_image_device_get_instance_private (self);
+  FpDeviceAction action;
+
+  action = fpi_device_get_current_action (FP_DEVICE (self));
+
+  g_return_if_fail (image != NULL);
+  g_return_if_fail (priv->state == FP_IMAGE_DEVICE_STATE_CAPTURE);
+  g_return_if_fail (action == FP_DEVICE_ACTION_ENROLL ||
+                    action == FP_DEVICE_ACTION_VERIFY ||
+                    action == FP_DEVICE_ACTION_IDENTIFY ||
+                    action == FP_DEVICE_ACTION_CAPTURE);
+
+  fp_image_device_change_state (self, FP_IMAGE_DEVICE_STATE_AWAIT_FINGER_OFF);
+
+  g_debug ("Image device captured an image");
+
+  /* XXX: We also detect minutiae in capture mode, we solely do this
+   *      to normalize the image which will happen as a by-product. */
+  fp_image_detect_minutiae (image,
+                            fpi_device_get_cancellable (FP_DEVICE (self)),
+                            fpi_image_device_minutiae_detected,
+                            self);
+}
+
+/**
+ * fpi_image_device_retry_scan:
+ * @self: a #FpImageDevice imaging fingerprint device
+ * @retry: The #FpDeviceRetry error code to report
+ *
+ * Reports a scan failure to the user. This may or may not abort the
+ * current session. It is the equivalent of fpi_image_device_image_captured()
+ * in the case of a retryable error condition (e.g. short swipe).
+ */
+void
+fpi_image_device_retry_scan (FpImageDevice *self, FpDeviceRetry retry)
+{
+  FpImageDevicePrivate *priv = fp_image_device_get_instance_private (self);
+  FpDeviceAction action;
+  GError *error;
+
+  action = fpi_device_get_current_action (FP_DEVICE (self));
+
+  /* We might be waiting for a finger at this point, so just accept
+   * all but INACTIVE */
+  g_return_if_fail (priv->state != FP_IMAGE_DEVICE_STATE_INACTIVE);
+  g_return_if_fail (action == FP_DEVICE_ACTION_ENROLL ||
+                    action == FP_DEVICE_ACTION_VERIFY ||
+                    action == FP_DEVICE_ACTION_IDENTIFY ||
+                    action == FP_DEVICE_ACTION_CAPTURE);
+
+  error = fpi_device_retry_new (retry);
+
+  if (action == FP_DEVICE_ACTION_ENROLL)
+    {
+      g_debug ("Reporting retry during enroll");
+      fpi_device_enroll_progress (FP_DEVICE (self), priv->enroll_stage, NULL, error);
+    }
+  else
+    {
+      /* We abort the operation and let the surrounding code retry in the
+       * non-enroll case (this is identical to a session error). */
+      g_debug ("Abort current operation due to retry (non-enroll case)");
+      fp_image_device_deactivate (FP_DEVICE (self));
+      fpi_device_action_error (FP_DEVICE (self), error);
+    }
+}
+
+/**
+ * fpi_image_device_session_error:
+ * @self: a #FpImageDevice imaging fingerprint device
+ * @error: The #GError to report
+ *
+ * Report an error while interacting with the device. This effectively
+ * aborts the current ongoing action.
+ */
+void
+fpi_image_device_session_error (FpImageDevice *self, GError *error)
+{
+  FpImageDevicePrivate *priv = fp_image_device_get_instance_private (self);
+
+  g_return_if_fail (self);
+
+  if (!error)
+    {
+      g_warning ("Driver did not provide an error, generating a generic one");
+      error = g_error_new (FP_DEVICE_ERROR, FP_DEVICE_ERROR_GENERAL, "Driver reported session error without an error");
+    }
+
+  if (!priv->active)
+    {
+      FpDeviceAction action = fpi_device_get_current_action (FP_DEVICE (self));
+      g_warning ("Driver reported session error, but device is inactive.");
+
+      if (action != FP_DEVICE_ACTION_NONE)
+        {
+          g_warning ("Translating to activation failure!");
+          fpi_image_device_activate_complete (self, error);
+          return;
+        }
+    }
+  else if (priv->state == FP_IMAGE_DEVICE_STATE_INACTIVE)
+    {
+      g_warning ("Driver reported session error; translating to deactivation failure.");
+      fpi_image_device_deactivate_complete (self, error);
+      return;
+    }
+
+  if (error->domain == FP_DEVICE_RETRY)
+    g_warning ("Driver should report retries using fpi_image_device_retry_scan!");
+
+  fp_image_device_deactivate (FP_DEVICE (self));
+  fpi_device_action_error (FP_DEVICE (self), error);
+}
+
+/**
+ * fpi_image_device_activate_complete:
+ * @self: a #FpImageDevice imaging fingerprint device
+ * @error: A #GError or %NULL on success
+ *
+ * Reports completion of device activation.
+ */
+void
+fpi_image_device_activate_complete (FpImageDevice *self, GError *error)
+{
+  FpImageDevicePrivate *priv = fp_image_device_get_instance_private (self);
+  FpDeviceAction action;
+
+  action = fpi_device_get_current_action (FP_DEVICE (self));
+
+  g_return_if_fail (priv->active == FALSE);
+  g_return_if_fail (action == FP_DEVICE_ACTION_ENROLL ||
+                    action == FP_DEVICE_ACTION_VERIFY ||
+                    action == FP_DEVICE_ACTION_IDENTIFY ||
+                    action == FP_DEVICE_ACTION_CAPTURE);
+
+  if (error)
+    {
+      g_debug ("Image device activation failed");
+      fpi_device_action_error (FP_DEVICE (self), error);
+      return;
+    }
+
+  g_debug ("Image device activation completed");
+
+  priv->active = TRUE;
+
+  /* We always want to capture at this point, move to AWAIT_FINGER
+   * state. */
+  fp_image_device_change_state (self, FP_IMAGE_DEVICE_STATE_AWAIT_FINGER_ON);
+}
+
+/**
+ * fpi_image_device_deactivate_complete:
+ * @self: a #FpImageDevice imaging fingerprint device
+ * @error: A #GError or %NULL on success
+ *
+ * Reports completion of device deactivation.
+ */
+void
+fpi_image_device_deactivate_complete (FpImageDevice *self, GError *error)
+{
+  FpImageDevicePrivate *priv = fp_image_device_get_instance_private (self);
+  FpImageDeviceClass *cls = FP_IMAGE_DEVICE_GET_CLASS (self);
+  FpDeviceAction action;
+
+  g_return_if_fail (priv->active == TRUE);
+  g_return_if_fail (priv->state == FP_IMAGE_DEVICE_STATE_INACTIVE);
+
+  g_debug ("Image device deactivation completed");
+
+  priv->active = FALSE;
+
+  /* Deactivation completed. As we deactivate in the background
+   * there may already be a new task pending. Check whether we
+   * need to do anything. */
+  action = fpi_device_get_current_action (FP_DEVICE (self));
+
+  /* Special case, if we should be closing, but didn't due to a running
+   * deactivation, then do so now. */
+  if (action == FP_DEVICE_ACTION_CLOSE)
+    {
+      cls->img_close (self);
+      return;
+    }
+
+  /* We might be waiting to be able to activate again. */
+  if (priv->pending_activation_timeout_id)
+    fp_image_device_activate (self);
+}
+
+/**
+ * fpi_image_device_open_complete:
+ * @self: a #FpImageDevice imaging fingerprint device
+ * @error: A #GError or %NULL on success
+ *
+ * Reports completion of open operation.
+ */
+void
+fpi_image_device_open_complete (FpImageDevice *self, GError *error)
+{
+  FpImageDevicePrivate *priv = fp_image_device_get_instance_private (self);
+  FpDeviceAction action;
+
+  action = fpi_device_get_current_action (FP_DEVICE (self));
+
+  g_return_if_fail (priv->active == FALSE);
+  g_return_if_fail (action == FP_DEVICE_ACTION_OPEN);
+
+  g_debug ("Image device open completed");
+
+  priv->state = FP_IMAGE_DEVICE_STATE_INACTIVE;
+
+  fpi_device_open_complete (FP_DEVICE (self), error);
+}
+
+/**
+ * fpi_image_device_close_complete:
+ * @self: a #FpImageDevice imaging fingerprint device
+ * @error: A #GError or %NULL on success
+ *
+ * Reports completion of close operation.
+ */
+void
+fpi_image_device_close_complete (FpImageDevice *self, GError *error)
+{
+  FpImageDevicePrivate *priv = fp_image_device_get_instance_private (self);
+  FpDeviceAction action;
+
+  action = fpi_device_get_current_action (FP_DEVICE (self));
+
+  g_debug ("Image device close completed");
+
+  g_return_if_fail (priv->active == FALSE);
+  g_return_if_fail (action == FP_DEVICE_ACTION_CLOSE);
+
+  priv->state = FP_IMAGE_DEVICE_STATE_INACTIVE;
+
+  fpi_device_close_complete (FP_DEVICE (self), error);
+}