elanspi: Do not allow image captures to be interrupted

Avoid unexpected state changes during image capture. This also means
that the old line handler does not need to check for cancellation.

doc/libfprint-2-sections.txt

@@ -247,6 +247,7 @@ fpi_ssm_new_full
 fpi_ssm_free
 fpi_ssm_start
 fpi_ssm_start_subsm
+fpi_ssm_set_critical
 fpi_ssm_next_state
 fpi_ssm_next_state_delayed
 fpi_ssm_jump_to_state
@@ -260,6 +261,7 @@ fpi_ssm_get_device
 fpi_ssm_get_error
 fpi_ssm_dup_error
 fpi_ssm_get_cur_state
+fpi_ssm_silence_debug
 fpi_ssm_spi_transfer_cb
 fpi_ssm_spi_transfer_with_weak_pointer_cb
 fpi_ssm_usb_transfer_cb

examples/enroll.c

@@ -35,6 +35,7 @@ typedef struct _EnrollData
   unsigned int  sigint_handler;
   FpFinger      finger;
   int           ret_value;
+  gboolean      update_fingerprint;
 } EnrollData;
 
 static void
@@ -84,7 +85,8 @@ on_enroll_completed (FpDevice *dev, GAsyncResult *res, void *user_data)
       /* Even if the device has storage, it may not be able to save all the
        * metadata that the print contains, so we can always save a local copy
        * containing the handle to the device print */
-      int r = print_data_save (print, enroll_data->finger);
+      int r = print_data_save (print, enroll_data->finger,
+                               enroll_data->update_fingerprint);
       if (r < 0)
         {
           g_warning ("Data save failed, code %d", r);
@@ -124,6 +126,40 @@ on_enroll_progress (FpDevice *device,
           fp_device_get_nr_enroll_stages (device));
 }
 
+static gboolean
+should_update_fingerprint (void)
+{
+  int update_choice;
+  gboolean update_fingerprint = FALSE;
+
+  printf ("Should an existing fingerprint be updated instead of being replaced (if present)? "
+          "Enter Y/y or N/n to make a choice.\n");
+  update_choice = getchar ();
+  if (update_choice == EOF)
+    {
+      g_warning ("EOF encountered while reading a character");
+      return EXIT_FAILURE;
+    }
+
+  switch (update_choice)
+    {
+    case 'y':
+    case 'Y':
+      update_fingerprint = TRUE;
+      break;
+
+    case 'n':
+    case 'N':
+      update_fingerprint = FALSE;
+      break;
+
+    default:
+      g_warning ("Invalid choice %c, should be Y/y or N/n.", update_choice);
+      return EXIT_FAILURE;
+    }
+  return update_fingerprint;
+}
+
 static void
 on_device_opened (FpDevice *dev, GAsyncResult *res, void *user_data)
 {
@@ -139,13 +175,26 @@ on_device_opened (FpDevice *dev, GAsyncResult *res, void *user_data)
       return;
     }
 
-  printf ("Opened device. It's now time to enroll your finger.\n\n");
+  printf ("Opened device.\n");
+
+  if (fp_device_has_feature (dev, FP_DEVICE_FEATURE_UPDATE_PRINT))
+    {
+      printf ("The device supports fingerprint updates.\n");
+      enroll_data->update_fingerprint = should_update_fingerprint ();
+    }
+  else
+    {
+      printf ("The device doesn't support fingerprint updates. Old prints will be erased.\n");
+      enroll_data->update_fingerprint = FALSE;
+    }
+
+  printf ("It's now time to enroll your finger.\n\n");
   printf ("You will need to successfully scan your %s finger %d times to "
           "complete the process.\n\n", finger_to_string (enroll_data->finger),
           fp_device_get_nr_enroll_stages (dev));
   printf ("Scan your finger now.\n");
 
-  print_template = print_create_template (dev, enroll_data->finger);
+  print_template = print_create_template (dev, enroll_data->finger, enroll_data->update_fingerprint);
   fp_device_enroll (dev, print_template, enroll_data->cancellable,
                     on_enroll_progress, NULL, NULL,
                     (GAsyncReadyCallback) on_enroll_completed,
@@ -171,11 +220,9 @@ main (void)
   FpDevice *dev;
   FpFinger finger;
 
-  g_print ("This program will enroll the selected finger, unconditionally "
-           "overwriting any print for the same finger that was enrolled "
-           "previously. If you want to continue, press enter, otherwise hit "
-           "Ctrl+C\n");
-  getchar ();
+  g_print ("This program will enroll the selected finger overwriting any print for the same"
+           " finger that was enrolled previously. Fingerprint updates without erasing old data"
+           " are possible on devices supporting that. Ctrl+C interrupts program execution.\n");
 
   g_print ("Choose the finger to enroll:\n");
   finger = finger_chooser ();

examples/storage.c

@@ -102,8 +102,23 @@ save_data (GVariant *data)
   return 0;
 }
 
+static FpPrint *
+load_print_from_data (GVariant *data)
+{
+  const guchar *stored_data = NULL;
+  gsize stored_len;
+  FpPrint *print;
+
+  g_autoptr(GError) error = NULL;
+  stored_data = (const guchar *) g_variant_get_fixed_array (data, &stored_len, 1);
+  print = fp_print_deserialize (stored_data, stored_len, &error);
+  if (error)
+    g_warning ("Error deserializing data: %s", error->message);
+  return print;
+}
+
 int
-print_data_save (FpPrint *print, FpFinger finger)
+print_data_save (FpPrint *print, FpFinger finger, gboolean update_fingerprint)
 {
   g_autofree gchar *descr = get_print_data_descriptor (print, NULL, finger);
 
@@ -137,25 +152,12 @@ print_data_load (FpDevice *dev, FpFinger finger)
 
   g_autoptr(GVariant) val = NULL;
   g_autoptr(GVariantDict) dict = NULL;
-  const guchar *stored_data = NULL;
-  gsize stored_len;
 
   dict = load_data ();
   val = g_variant_dict_lookup_value (dict, descr, G_VARIANT_TYPE ("ay"));
 
   if (val)
-    {
-      FpPrint *print;
-      g_autoptr(GError) error = NULL;
-
-      stored_data = (const guchar *) g_variant_get_fixed_array (val, &stored_len, 1);
-      print = fp_print_deserialize (stored_data, stored_len, &error);
-
-      if (error)
-        g_warning ("Error deserializing data: %s", error->message);
-
-      return print;
-    }
+    return load_print_from_data (val);
 
   return NULL;
 }
@@ -207,16 +209,30 @@ gallery_data_load (FpDevice *dev)
 }
 
 FpPrint *
-print_create_template (FpDevice *dev, FpFinger finger)
+print_create_template (FpDevice *dev, FpFinger finger, gboolean load_existing)
 {
+  g_autoptr(GVariantDict) dict = NULL;
   g_autoptr(GDateTime) datetime = NULL;
   g_autoptr(GDate) date = NULL;
+  g_autoptr(GVariant) existing_val = NULL;
+  g_autofree gchar *descr = get_print_data_descriptor (NULL, dev, finger);
   FpPrint *template = NULL;
   gint year, month, day;
 
-  template = fp_print_new (dev);
-  fp_print_set_finger (template, finger);
-  fp_print_set_username (template, g_get_user_name ());
+  if (load_existing)
+    {
+      dict = load_data ();
+      existing_val = g_variant_dict_lookup_value (dict, descr, G_VARIANT_TYPE ("ay"));
+      if (existing_val != NULL)
+        template = load_print_from_data (existing_val);
+    }
+  if (template == NULL)
+    {
+      template = fp_print_new (dev);
+      fp_print_set_finger (template, finger);
+      fp_print_set_username (template, g_get_user_name ());
+    }
+
   datetime = g_date_time_new_now_local ();
   g_date_time_get_ymd (datetime, &year, &month, &day);
   date = g_date_new_dmy (day, month, year);

examples/storage.h

@@ -21,12 +21,14 @@
 #pragma once
 
 int print_data_save (FpPrint *print,
-                     FpFinger finger);
+                     FpFinger finger,
+                     gboolean update_fingerprint);
 FpPrint * print_data_load (FpDevice *dev,
                            FpFinger  finger);
 GPtrArray * gallery_data_load (FpDevice *dev);
-FpPrint * print_create_template (FpDevice *dev,
-                                 FpFinger  finger);
+FpPrint * print_create_template (FpDevice      *dev,
+                                 FpFinger       finger,
+                                 const gboolean load_existing);
 gboolean print_image_save (FpPrint    *print,
                            const char *path);
 gboolean save_image_to_pgm (FpImage    *img,

libfprint/drivers/elanspi.c

@@ -434,21 +434,9 @@ elanspi_capture_old_line_handler (FpiSpiTransfer *transfer, FpDevice *dev, gpoin
   self->old_data.line_ptr += 1;
   /* if there is still data, continue from check lineready */
   if (self->old_data.line_ptr < self->sensor_height)
-    {
-      fpi_ssm_jump_to_state (transfer->ssm, ELANSPI_CAPTOLD_CHECK_LINEREADY);
-    }
+    fpi_ssm_jump_to_state (transfer->ssm, ELANSPI_CAPTOLD_CHECK_LINEREADY);
   else
-    {
-      /* check for cancellation */
-      if (fpi_device_action_is_cancelled (dev))
-        {
-          g_cancellable_set_error_if_cancelled (fpi_device_get_cancellable (dev), &error);
-          fpi_ssm_mark_failed (transfer->ssm, error);
-          return;
-        }
-      /* otherwise finish succesfully */
-      fpi_ssm_mark_completed (transfer->ssm);
-    }
+    fpi_ssm_mark_completed (transfer->ssm);
 }
 
 static void
@@ -606,6 +594,8 @@ elanspi_calibrate_old_handler (FpiSsm *ssm, FpDevice *dev)
     case ELANSPI_CALIBOLD_CHECKFIN_CAPTURE:
     case ELANSPI_CALIBOLD_DACFINE_CAPTURE:
       chld = fpi_ssm_new (dev, elanspi_capture_old_handler, ELANSPI_CAPTOLD_NSTATES);
+      fpi_ssm_silence_debug (chld);
+      fpi_ssm_set_critical (chld);
       fpi_ssm_start_subsm (ssm, chld);
       return;
 
@@ -860,6 +850,8 @@ elanspi_calibrate_hv_handler (FpiSsm *ssm, FpDevice *dev)
 
     case ELANSPI_CALIBHV_CAPTURE:
       chld = fpi_ssm_new (dev, elanspi_capture_hv_handler, ELANSPI_CAPTHV_NSTATES);
+      fpi_ssm_silence_debug (chld);
+      fpi_ssm_set_critical (chld);
       fpi_ssm_start_subsm (ssm, chld);
       return;
 
@@ -1115,6 +1107,8 @@ do_sw_reset:
         chld = fpi_ssm_new_full (dev, elanspi_calibrate_hv_handler, ELANSPI_CALIBHV_NSTATES, ELANSPI_CALIBHV_PROTECT, "HV calibrate");
       else
         chld = fpi_ssm_new_full (dev, elanspi_calibrate_old_handler, ELANSPI_CALIBOLD_NSTATES, ELANSPI_CALIBOLD_PROTECT, "old calibrate");
+      fpi_ssm_silence_debug (chld);
+      fpi_ssm_set_critical (chld);
       fpi_ssm_start_subsm (ssm, chld);
       return;
 
@@ -1123,6 +1117,8 @@ do_sw_reset:
         chld = fpi_ssm_new (dev, elanspi_capture_hv_handler, ELANSPI_CAPTHV_NSTATES);
       else
         chld = fpi_ssm_new (dev, elanspi_capture_old_handler, ELANSPI_CAPTOLD_NSTATES);
+      fpi_ssm_silence_debug (chld);
+      fpi_ssm_set_critical (chld);
       fpi_ssm_start_subsm (ssm, chld);
       return;
 
@@ -1219,8 +1215,6 @@ elanspi_guess_image (FpiDeviceElanSpi *self, guint16 *raw_image)
 
   sq_stddev /= (frame_width * frame_height);
 
-  fp_dbg ("<guess> stddev=%" G_GUINT64_FORMAT "d, ip=%d, is_fp=%d, is_empty=%d", sq_stddev, invalid_percent, is_fp, is_empty);
-
   if (invalid_percent < ELANSPI_MAX_REAL_INVALID_PERCENT)
     is_fp += 1;
   if (invalid_percent > ELANSPI_MIN_EMPTY_INVALID_PERCENT)
@@ -1231,6 +1225,8 @@ elanspi_guess_image (FpiDeviceElanSpi *self, guint16 *raw_image)
   if (sq_stddev < ELANSPI_MAX_EMPTY_STDDEV)
     is_empty += 1;
 
+  fp_dbg ("<guess> stddev=%" G_GUINT64_FORMAT "d, ip=%d, is_fp=%d, is_empty=%d", sq_stddev, invalid_percent, is_fp, is_empty);
+
   if (is_fp > is_empty)
     return ELANSPI_GUESS_FINGERPRINT;
   else if (is_empty > is_fp)
@@ -1495,6 +1491,8 @@ elanspi_fp_capture_ssm_handler (FpiSsm *ssm, FpDevice *dev)
         chld = fpi_ssm_new (dev, elanspi_capture_hv_handler, ELANSPI_CAPTHV_NSTATES);
       else
         chld = fpi_ssm_new (dev, elanspi_capture_old_handler, ELANSPI_CAPTOLD_NSTATES);
+      fpi_ssm_silence_debug (chld);
+      fpi_ssm_set_critical (chld);
       fpi_ssm_start_subsm (ssm, chld);
       return;
 

libfprint/fp-context.c

@@ -426,6 +426,7 @@ void
 fp_context_enumerate (FpContext *context)
 {
   FpContextPrivate *priv = fp_context_get_instance_private (context);
+  gboolean dispatched;
   gint i;
 
   g_return_if_fail (FP_IS_CONTEXT (context));
@@ -564,8 +565,19 @@ fp_context_enumerate (FpContext *context)
   }
 #endif
 
-  while (priv->pending_devices)
-    g_main_context_iteration (NULL, TRUE);
+  /* Iterate until 1. we have no pending devices, and 2. the mainloop is idle
+   * This takes care of processing hotplug events that happened during
+   * enumeration.
+   * This is important due to USB `persist` being turned off. At resume time,
+   * devices will disappear and immediately re-appear. In this situation,
+   * enumerate could first see the old state with a removed device resulting
+   * in it to not be discovered.
+   * As a hotplug event is seemingly emitted by the kernel immediately, we can
+   * simply make sure to process all events before returning from enumerate.
+   */
+  dispatched = TRUE;
+  while (priv->pending_devices || dispatched)
+    dispatched = g_main_context_iteration (NULL, !!priv->pending_devices);
 }
 
 /**

libfprint/fp-device.c

@@ -1189,10 +1189,11 @@ fp_device_resume_finish (FpDevice     *device,
  * fp_device_enroll_finish().
  *
  * The @template_print parameter is a #FpPrint with available metadata filled
- * in. The driver may make use of this metadata, when e.g. storing the print on
- * device memory. It is undefined whether this print is filled in by the driver
- * and returned, or whether the driver will return a newly created print after
- * enrollment succeeded.
+ * in and, optionally, with existing fingerprint data to be updated with newly
+ * enrolled fingerprints if a device driver supports it. The driver may make use
+ * of the metadata, when e.g. storing the print on device memory. It is undefined
+ * whether this print is filled in by the driver and returned, or whether the
+ * driver will return a newly created print after enrollment succeeded.
  */
 void
 fp_device_enroll (FpDevice           *device,
@@ -1229,19 +1230,30 @@ fp_device_enroll (FpDevice           *device,
 
   if (!FP_IS_PRINT (template_print))
     {
-      g_warning ("User did not pass a print template!");
       g_task_return_error (task,
-                           fpi_device_error_new (FP_DEVICE_ERROR_DATA_INVALID));
+                           fpi_device_error_new_msg (FP_DEVICE_ERROR_DATA_INVALID,
+                                                     "User did not pass a print template!"));
       return;
     }
 
   g_object_get (template_print, "fpi-type", &print_type, NULL);
   if (print_type != FPI_PRINT_UNDEFINED)
     {
-      g_warning ("Passed print template must be newly created and blank!");
-      g_task_return_error (task,
-                           fpi_device_error_new (FP_DEVICE_ERROR_DATA_INVALID));
-      return;
+      if (!fp_device_has_feature (device, FP_DEVICE_FEATURE_UPDATE_PRINT))
+        {
+          g_task_return_error (task,
+                               fpi_device_error_new_msg (FP_DEVICE_ERROR_DATA_INVALID,
+                                                         "A device does not support print updates!"));
+          return;
+        }
+      if (!fp_print_compatible (template_print, device))
+        {
+          g_task_return_error (task,
+                               fpi_device_error_new_msg (FP_DEVICE_ERROR_DATA_INVALID,
+                                                         "The print and device must have a matching driver and device id"
+                                                         " for a fingerprint update to succeed"));
+          return;
+        }
     }
 
   priv->current_action = FPI_DEVICE_ACTION_ENROLL;

libfprint/fp-device.h

@@ -59,6 +59,7 @@ typedef enum {
  * @FP_DEVICE_FEATURE_STORAGE_CLEAR: Supports clearing the whole storage
  * @FP_DEVICE_FEATURE_DUPLICATES_CHECK: Natively supports duplicates detection
  * @FP_DEVICE_FEATURE_ALWAYS_ON: Whether the device can run continuously
+ * @FP_DEVICE_FEATURE_UPDATE_PRINT: Supports updating an existing print record using new scans
  */
 typedef enum /*< flags >*/ {
   FP_DEVICE_FEATURE_NONE = 0,
@@ -71,6 +72,7 @@ typedef enum /*< flags >*/ {
   FP_DEVICE_FEATURE_STORAGE_CLEAR = 1 << 6,
   FP_DEVICE_FEATURE_DUPLICATES_CHECK = 1 << 7,
   FP_DEVICE_FEATURE_ALWAYS_ON = 1 << 8,
+  FP_DEVICE_FEATURE_UPDATE_PRINT = 1 << 9,
 } FpDeviceFeature;
 
 /**

libfprint/fp-image-device.c

@@ -101,6 +101,7 @@ fp_image_device_start_capture_action (FpDevice *device)
   FpImageDevice *self = FP_IMAGE_DEVICE (device);
   FpImageDevicePrivate *priv = fp_image_device_get_instance_private (self);
   FpiDeviceAction action;
+  FpiPrintType print_type;
 
   /* There is just one action that we cannot support out
    * of the box, which is a capture without first waiting
@@ -124,7 +125,9 @@ fp_image_device_start_capture_action (FpDevice *device)
       FpPrint *enroll_print = NULL;
 
       fpi_device_get_enroll_data (device, &enroll_print);
-      fpi_print_set_type (enroll_print, FPI_PRINT_NBIS);
+      g_object_get (enroll_print, "fpi-type", &print_type, NULL);
+      if (print_type != FPI_PRINT_NBIS)
+        fpi_print_set_type (enroll_print, FPI_PRINT_NBIS);
     }
 
   priv->enroll_stage = 0;
@@ -221,6 +224,7 @@ fp_image_device_class_init (FpImageDeviceClass *klass)
   fp_device_class->cancel = fp_image_device_cancel_action;
 
   fpi_device_class_auto_initialize_features (fp_device_class);
+  fp_device_class->features |= FP_DEVICE_FEATURE_UPDATE_PRINT;
 
   /* Default implementations */
   klass->activate = fp_image_device_default_activate;

libfprint/fp-print.c

@@ -61,6 +61,7 @@ enum {
   /* Private property*/
   PROP_FPI_TYPE,
   PROP_FPI_DATA,
+  PROP_FPI_PRINTS,
   N_PROPS
 };
 
@@ -133,6 +134,10 @@ fp_print_get_property (GObject    *object,
       g_value_set_variant (value, self->data);
       break;
 
+    case PROP_FPI_PRINTS:
+      g_value_set_pointer (value, self->prints);
+      break;
+
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
     }
@@ -188,6 +193,11 @@ fp_print_set_property (GObject      *object,
       self->data = g_value_dup_variant (value);
       break;
 
+    case PROP_FPI_PRINTS:
+      g_clear_pointer (&self->prints, g_ptr_array_unref);
+      self->prints = g_value_get_pointer (value);
+      break;
+
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
     }
@@ -299,6 +309,19 @@ fp_print_class_init (FpPrintClass *klass)
                           NULL,
                           G_PARAM_STATIC_STRINGS | G_PARAM_READWRITE);
 
+  /**
+   * FpPrint::fpi-prints: (skip)
+   *
+   * This property is only for internal purposes.
+   *
+   * Stability: private
+   */
+  properties[PROP_FPI_PRINTS] =
+    g_param_spec_pointer ("fpi-prints",
+                          "Prints",
+                          "Prints for internal use only",
+                          G_PARAM_STATIC_STRINGS | G_PARAM_READWRITE);
+
   g_object_class_install_properties (object_class, N_PROPS, properties);
 }
 

libfprint/fpi-device.h

@@ -25,9 +25,11 @@
 #include "fpi-print.h"
 
 /**
- * FpiDeviceUdevSubtype:
+ * FpiDeviceUdevSubtypeFlags:
  * @FPI_DEVICE_UDEV_SUBTYPE_SPIDEV: The device requires an spidev node
  * @FPI_DEVICE_UDEV_SUBTYPE_HIDRAW: The device requires a hidraw node
+ *
+ * Bitfield of required hardware resources for a udev-backed device.
  */
 typedef enum {
   FPI_DEVICE_UDEV_SUBTYPE_SPIDEV = 1 << 0,

libfprint/fpi-ssm.c

@@ -81,6 +81,8 @@ struct _FpiSsm
   int                     start_cleanup;
   int                     cur_state;
   gboolean                completed;
+  gboolean                critical;
+  gboolean                silence;
   GSource                *timeout;
   GError                 *error;
   FpiSsmCompletedCallback callback;
@@ -245,10 +247,11 @@ fpi_ssm_free (FpiSsm *machine)
 
 /* Invoke the state handler */
 static void
-__ssm_call_handler (FpiSsm *machine)
+__ssm_call_handler (FpiSsm *machine, gboolean force_msg)
 {
-  fp_dbg ("[%s] %s entering state %d", fp_device_get_driver (machine->dev),
-          machine->name, machine->cur_state);
+  if (force_msg || !machine->silence)
+    fp_dbg ("[%s] %s entering state %d", fp_device_get_driver (machine->dev),
+            machine->name, machine->cur_state);
   machine->handler (machine, machine->dev);
 }
 
@@ -275,7 +278,11 @@ fpi_ssm_start (FpiSsm *ssm, FpiSsmCompletedCallback callback)
   ssm->cur_state = 0;
   ssm->completed = FALSE;
   ssm->error = NULL;
-  __ssm_call_handler (ssm);
+
+  if (ssm->critical)
+    fpi_device_critical_enter (ssm->dev);
+
+  __ssm_call_handler (ssm, TRUE);
 }
 
 static void
@@ -346,7 +353,7 @@ fpi_ssm_mark_completed (FpiSsm *machine)
   if (next_state < machine->nr_states)
     {
       machine->cur_state = next_state;
-      __ssm_call_handler (machine);
+      __ssm_call_handler (machine, TRUE);
       return;
     }
 
@@ -364,6 +371,10 @@ fpi_ssm_mark_completed (FpiSsm *machine)
 
       machine->callback (machine, machine->dev, error);
     }
+
+  if (machine->critical)
+    fpi_device_critical_leave (machine->dev);
+
   fpi_ssm_free (machine);
 }
 
@@ -460,7 +471,7 @@ fpi_ssm_next_state (FpiSsm *machine)
   if (machine->cur_state == machine->nr_states)
     fpi_ssm_mark_completed (machine);
   else
-    __ssm_call_handler (machine);
+    __ssm_call_handler (machine, FALSE);
 }
 
 void
@@ -537,7 +548,7 @@ fpi_ssm_jump_to_state (FpiSsm *machine, int state)
   if (machine->cur_state == machine->nr_states)
     fpi_ssm_mark_completed (machine);
   else
-    __ssm_call_handler (machine);
+    __ssm_call_handler (machine, FALSE);
 }
 
 typedef struct
@@ -642,6 +653,39 @@ fpi_ssm_dup_error (FpiSsm *machine)
   return NULL;
 }
 
+/**
+ * fpi_ssm_silence_debug:
+ * @machine: an #FpiSsm state machine
+ *
+ * Turn off state change debug messages from this SSM. This does not disable
+ * all messages, as e.g. the initial state, SSM completion and cleanup states
+ * are still printed out.
+ *
+ * Use if the SSM loops and would flood the debug log otherwise.
+ */
+void
+fpi_ssm_silence_debug (FpiSsm *machine)
+{
+  machine->silence = TRUE;
+}
+
+/**
+ * fpi_ssm_set_critical:
+ * @machine: an #FpiSsm state machine
+ *
+ * Sets up the SSM to hold a critical section in the driver code. See
+ * fpi_device_critical_enter() for more details. This is useful if the SSM must
+ * not be interrupted in order to keep the device in a good state. You can e.g.
+ * guarantee that an image transfer is completed.
+ *
+ * This function must be called before starting the SSM.
+ */
+void
+fpi_ssm_set_critical (FpiSsm *machine)
+{
+  machine->critical = TRUE;
+}
+
 /**
  * fpi_ssm_usb_transfer_cb:
  * @transfer: a #FpiUsbTransfer

libfprint/fpi-ssm.h

@@ -96,6 +96,9 @@ GError * fpi_ssm_get_error (FpiSsm *machine);
 GError * fpi_ssm_dup_error (FpiSsm *machine);
 int fpi_ssm_get_cur_state (FpiSsm *machine);
 
+void fpi_ssm_silence_debug (FpiSsm *machine);
+void fpi_ssm_set_critical (FpiSsm *machine);
+
 /* Callbacks to be used by the driver instead of implementing their own
  * logic.
  */

tests/test-fpi-device.c

@@ -27,6 +27,7 @@
 #include "fpi-compat.h"
 #include "fpi-log.h"
 #include "test-device-fake.h"
+#include "fp-print-private.h"
 
 /* Utility functions */
 
@@ -142,6 +143,16 @@ make_fake_print (FpDevice *device,
   return enrolled_print;
 }
 
+static FpPrint *
+make_fake_nbis_print (FpDevice *device)
+{
+  FpPrint *enrolled_print = fp_print_new (device);
+
+  fpi_print_set_type (enrolled_print, FPI_PRINT_NBIS);
+
+  return enrolled_print;
+}
+
 static FpPrint *
 make_fake_print_reffed (FpDevice *device,
                         GVariant *print_data)
@@ -1045,7 +1056,6 @@ test_driver_enroll_error_no_print (void)
   out_print =
     fp_device_enroll_sync (device, fp_print_new (device), NULL, NULL, NULL, &error);
 
-  g_test_assert_expected_messages ();
   g_assert (fake_dev->last_called_function == dev_class->enroll);
   g_assert_error (error, FP_DEVICE_ERROR, FP_DEVICE_ERROR_GENERAL);
   g_assert_null (out_print);
@@ -1053,6 +1063,111 @@ test_driver_enroll_error_no_print (void)
   g_clear_error (&error);
 }
 
+static void
+test_driver_enroll_update_nbis (void)
+{
+  g_autoptr(GError) error = NULL;
+  g_autoptr(FpAutoResetClass) dev_class = auto_reset_device_class ();
+  g_autoptr(FpAutoCloseDevice) device = NULL;
+  g_autoptr(FpPrint) template_print = NULL;
+  FpiDeviceFake *fake_dev = NULL;
+  FpPrint *out_print = NULL;
+
+  dev_class->features |= FP_DEVICE_FEATURE_UPDATE_PRINT;
+  device = auto_close_fake_device_new ();
+  fake_dev = FPI_DEVICE_FAKE (device);
+
+  template_print = make_fake_nbis_print (device);
+  fake_dev->ret_print = template_print;
+
+  out_print =
+    fp_device_enroll_sync (device, template_print, NULL, NULL, NULL, &error);
+
+  g_assert (fake_dev->last_called_function == dev_class->enroll);
+  g_assert (fake_dev->action_data == template_print);
+
+  g_assert_no_error (error);
+  g_assert (out_print == template_print);
+}
+
+static void
+test_driver_enroll_update_nbis_wrong_device (void)
+{
+  g_autoptr(GError) error = NULL;
+  g_autoptr(FpAutoResetClass) dev_class = auto_reset_device_class ();
+  g_autoptr(FpAutoCloseDevice) device = NULL;
+  g_autoptr(FpPrint) template_print = NULL;
+  FpiDeviceFake *fake_dev = NULL;
+  FpPrint *out_print = NULL;
+
+  dev_class->features |= FP_DEVICE_FEATURE_UPDATE_PRINT;
+
+  device = auto_close_fake_device_new ();
+  fake_dev = FPI_DEVICE_FAKE (device);
+
+  template_print = make_fake_nbis_print (device);
+  template_print->device_id = g_strdup ("wrong_device");
+  fake_dev->ret_print = template_print;
+
+  out_print =
+    fp_device_enroll_sync (device, template_print, NULL, NULL, NULL, &error);
+
+  g_assert_error (error, FP_DEVICE_ERROR, FP_DEVICE_ERROR_DATA_INVALID);
+  g_assert (out_print == NULL);
+}
+
+static void
+test_driver_enroll_update_nbis_wrong_driver (void)
+{
+  g_autoptr(GError) error = NULL;
+  g_autoptr(FpAutoResetClass) dev_class = auto_reset_device_class ();
+  g_autoptr(FpAutoCloseDevice) device = NULL;
+  g_autoptr(FpPrint) template_print = NULL;
+  FpiDeviceFake *fake_dev = NULL;
+  FpPrint *out_print = NULL;
+
+  dev_class->features |= FP_DEVICE_FEATURE_UPDATE_PRINT;
+
+  device = auto_close_fake_device_new ();
+  fake_dev = FPI_DEVICE_FAKE (device);
+
+  template_print = make_fake_nbis_print (device);
+  template_print->driver = g_strdup ("wrong_driver");
+  fake_dev->ret_print = template_print;
+
+  out_print =
+    fp_device_enroll_sync (device, template_print, NULL, NULL, NULL, &error);
+
+  g_assert_error (error, FP_DEVICE_ERROR, FP_DEVICE_ERROR_DATA_INVALID);
+  g_assert (out_print == NULL);
+}
+
+static void
+test_driver_enroll_update_nbis_missing_feature (void)
+{
+  g_autoptr(GError) error = NULL;
+  g_autoptr(FpAutoResetClass) dev_class = auto_reset_device_class ();
+  g_autoptr(FpAutoCloseDevice) device = NULL;
+  g_autoptr(FpPrint) template_print = NULL;
+  FpiDeviceFake *fake_dev = NULL;
+  FpPrint *out_print = NULL;
+
+  device = auto_close_fake_device_new ();
+  fake_dev = FPI_DEVICE_FAKE (device);
+
+  template_print = make_fake_nbis_print (device);
+  fake_dev->ret_print = template_print;
+
+  out_print =
+    fp_device_enroll_sync (device, template_print, NULL, NULL, NULL, &error);
+
+  g_assert (fake_dev->last_called_function == dev_class->open);
+  g_assert (fake_dev->action_data == NULL);
+
+  g_assert_error (error, FP_DEVICE_ERROR, FP_DEVICE_ERROR_DATA_INVALID);
+  g_assert (out_print == NULL);
+}
+
 typedef struct
 {
   gint     completed_stages;
@@ -3306,6 +3421,13 @@ main (int argc, char *argv[])
   g_test_add_func ("/driver/enroll/error", test_driver_enroll_error);
   g_test_add_func ("/driver/enroll/error/no_print", test_driver_enroll_error_no_print);
   g_test_add_func ("/driver/enroll/progress", test_driver_enroll_progress);
+  g_test_add_func ("/driver/enroll/update_nbis", test_driver_enroll_update_nbis);
+  g_test_add_func ("/driver/enroll/update_nbis_wrong_device",
+                   test_driver_enroll_update_nbis_wrong_device);
+  g_test_add_func ("/driver/enroll/update_nbis_wrong_driver",
+                   test_driver_enroll_update_nbis_wrong_driver);
+  g_test_add_func ("/driver/enroll/update_nbis_missing_feature",
+                   test_driver_enroll_update_nbis_missing_feature);
   g_test_add_func ("/driver/verify", test_driver_verify);
   g_test_add_func ("/driver/verify/fail", test_driver_verify_fail);
   g_test_add_func ("/driver/verify/retry", test_driver_verify_retry);

tests/virtual-image.py

@@ -136,6 +136,7 @@ class VirtualImage(unittest.TestCase):
         self.assertTrue(self.dev.has_feature(FPrint.DeviceFeature.CAPTURE))
         self.assertTrue(self.dev.has_feature(FPrint.DeviceFeature.IDENTIFY))
         self.assertTrue(self.dev.has_feature(FPrint.DeviceFeature.VERIFY))
+        self.assertTrue(self.dev.has_feature(FPrint.DeviceFeature.UPDATE_PRINT))
         self.assertFalse(self.dev.has_feature(FPrint.DeviceFeature.DUPLICATES_CHECK))
         self.assertFalse(self.dev.has_feature(FPrint.DeviceFeature.STORAGE))
         self.assertFalse(self.dev.has_feature(FPrint.DeviceFeature.STORAGE_LIST))
@@ -144,7 +145,8 @@ class VirtualImage(unittest.TestCase):
         self.assertEqual(self.dev.get_features(),
                          FPrint.DeviceFeature.CAPTURE |
                          FPrint.DeviceFeature.IDENTIFY |
-                         FPrint.DeviceFeature.VERIFY)
+                         FPrint.DeviceFeature.VERIFY |
+                         FPrint.DeviceFeature.UPDATE_PRINT)
 
     def test_capture_prevents_close(self):
         cancel = Gio.Cancellable()
@@ -167,7 +169,7 @@ class VirtualImage(unittest.TestCase):
         while not self._cancelled:
             ctx.iteration(True)
 
-    def enroll_print(self, image):
+    def enroll_print(self, image, template=None):
         self._step = 0
         self._enrolled = None
 
@@ -181,14 +183,15 @@ class VirtualImage(unittest.TestCase):
             self.assertEqual(self.dev.get_finger_status(), FPrint.FingerStatusFlags.NONE)
             self._enrolled = fp
 
-        template = FPrint.Print.new(self.dev)
-        template.props.finger = FPrint.Finger.LEFT_THUMB
-        template.props.username = "testuser"
-        template.props.description = "test print"
-        datetime = GLib.DateTime.new_now_local()
-        date = GLib.Date()
-        date.set_dmy(*datetime.get_ymd()[::-1])
-        template.props.enroll_date = date
+        if template is None:
+            template = FPrint.Print.new(self.dev)
+            template.props.finger = FPrint.Finger.LEFT_THUMB
+            template.props.username = "testuser"
+            template.props.description = "test print"
+            datetime = GLib.DateTime.new_now_local()
+            date = GLib.Date()
+            date.set_dmy(*datetime.get_ymd()[::-1])
+            template.props.enroll_date = date
         self.assertEqual(self.dev.get_finger_status(), FPrint.FingerStatusFlags.NONE)
         self.dev.enroll(template, None, progress_cb, tuple(), done_cb)
 
@@ -264,6 +267,28 @@ class VirtualImage(unittest.TestCase):
             ctx.iteration(True)
         assert(not self._verify_match)
 
+        # Test fingerprint updates
+        # Enroll a second print
+        fp_whorl_tended_arch = self.enroll_print('tented_arch', fp_whorl)
+
+        # Make sure the first print verifies successfully after the update
+        self._verify_match = None
+        self._verify_fp = None
+        self.dev.verify(fp_whorl_tended_arch, callback=verify_cb)
+        self.send_image('whorl')
+        while self._verify_match is None:
+            ctx.iteration(True)
+        assert(self._verify_match)
+
+        # Make sure the second print verifies successfully after the update
+        self._verify_match = None
+        self._verify_fp = None
+        self.dev.verify(fp_whorl_tended_arch, callback=verify_cb)
+        self.send_image('tented_arch')
+        while self._verify_match is None:
+            ctx.iteration(True)
+        assert(self._verify_match)
+
         # Test verify error cases
         self._verify_fp = None
         self._verify_error = None