fp-device: Add finger-status property

It can be used by drivers to report the state of the finger on sensor

libfprint/fp-device-private.h

@@ -49,7 +49,8 @@ typedef struct
   GSource            *current_task_idle_return_source;
 
   /* State for tasks */
-  gboolean wait_for_finger;
+  gboolean            wait_for_finger;
+  FpFingerStatusFlags finger_status;
 } FpDevicePrivate;
 
 

libfprint/fp-device.c

@@ -46,6 +46,7 @@ enum {
   PROP_OPEN,
   PROP_NR_ENROLL_STAGES,
   PROP_SCAN_TYPE,
+  PROP_FINGER_STATUS,
   PROP_FPI_ENVIRON,
   PROP_FPI_USB_DEVICE,
   PROP_FPI_DRIVER_DATA,
@@ -181,6 +182,10 @@ fp_device_get_property (GObject    *object,
       g_value_set_enum (value, priv->scan_type);
       break;
 
+    case PROP_FINGER_STATUS:
+      g_value_set_enum (value, priv->finger_status);
+      break;
+
     case PROP_DRIVER:
       g_value_set_static_string (value, FP_DEVICE_GET_CLASS (priv)->id);
       break;
@@ -310,6 +315,13 @@ fp_device_class_init (FpDeviceClass *klass)
                        FP_TYPE_SCAN_TYPE, FP_SCAN_TYPE_SWIPE,
                        G_PARAM_STATIC_STRINGS | G_PARAM_READABLE);
 
+  properties[PROP_FINGER_STATUS] =
+    g_param_spec_flags ("finger-status",
+                        "FingerStatus",
+                        "The status of the finger",
+                        FP_TYPE_FINGER_STATUS_FLAGS, FP_FINGER_STATUS_NONE,
+                        G_PARAM_STATIC_STRINGS | G_PARAM_READABLE);
+
   properties[PROP_DRIVER] =
     g_param_spec_string ("driver",
                          "Driver",
@@ -469,6 +481,26 @@ fp_device_get_scan_type (FpDevice *device)
   return priv->scan_type;
 }
 
+/**
+ * fp_device_get_finger_status:
+ * @device: A #FpDevice
+ *
+ * Retrieves the finger status flags for the device.
+ * This can be used by the UI to present the relevant feedback, although it
+ * is not guaranteed to be a relevant value when not performing any action.
+ *
+ * Returns: The current #FpFingerStatusFlags
+ */
+FpFingerStatusFlags
+fp_device_get_finger_status (FpDevice *device)
+{
+  FpDevicePrivate *priv = fp_device_get_instance_private (device);
+
+  g_return_val_if_fail (FP_IS_DEVICE (device), FP_SCAN_TYPE_SWIPE);
+
+  return priv->finger_status;
+}
+
 /**
  * fp_device_get_nr_enroll_stages:
  * @device: A #FpDevice

libfprint/fp-device.h

@@ -170,6 +170,7 @@ const gchar *fp_device_get_device_id (FpDevice *device);
 const gchar *fp_device_get_name (FpDevice *device);
 gboolean     fp_device_is_open (FpDevice *device);
 FpScanType   fp_device_get_scan_type (FpDevice *device);
+FpFingerStatusFlags fp_device_get_finger_status (FpDevice *device);
 gint         fp_device_get_nr_enroll_stages (FpDevice *device);
 
 gboolean     fp_device_supports_identify (FpDevice *device);

libfprint/fp-print.h

@@ -66,6 +66,18 @@ typedef enum {
   FP_FINGER_LAST = FP_FINGER_RIGHT_LITTLE,
 } FpFinger;
 
+/**
+ * FpFingerStatusFlags:
+ * @FP_FINGER_STATUS_NONE: Sensor has not the finger on it, nor requires it
+ * @FP_FINGER_STATUS_NEEDED: Sensor waits for the finger
+ * @FP_FINGER_STATUS_PRESENT: Sensor has the finger on it
+ */
+typedef enum {
+  FP_FINGER_STATUS_NONE    = 0,
+  FP_FINGER_STATUS_NEEDED  = 1 << 0,
+  FP_FINGER_STATUS_PRESENT = 1 << 1,
+} FpFingerStatusFlags;
+
 FpPrint *fp_print_new (FpDevice *device);
 
 FpPrint *fp_print_new_from_data (guchar *data,

libfprint/fpi-device.c

@@ -1394,3 +1394,59 @@ fpi_device_identify_report (FpDevice *device,
   if (call_cb && data->match_cb)
     data->match_cb (device, data->match, data->print, data->match_data, data->error);
 }
+
+/**
+ * fpi_device_report_finger_status:
+ * @device: The #FpDevice
+ * @finger_status: The current #FpFingerStatusFlags to report
+ *
+ * Report the finger status for the @device.
+ * This can be used by UI to give a feedback
+ *
+ * Returns: %TRUE if changed
+ */
+gboolean
+fpi_device_report_finger_status (FpDevice           *device,
+                                 FpFingerStatusFlags finger_status)
+{
+  FpDevicePrivate *priv = fp_device_get_instance_private (device);
+  g_autofree char *status_string = NULL;
+
+  if (priv->finger_status == finger_status)
+    return FALSE;
+
+  status_string = g_flags_to_string (FP_TYPE_FINGER_STATUS_FLAGS, finger_status);
+  fp_dbg ("Device reported finger status change: %s", status_string);
+
+  priv->finger_status = finger_status;
+  g_object_notify (G_OBJECT (device), "finger-status");
+
+  return TRUE;
+}
+
+/**
+ * fpi_device_report_finger_status_changes:
+ * @device: The #FpDevice
+ * @added_status: The #FpFingerStatusFlags to add
+ * @added_status: The #FpFingerStatusFlags to remove
+ *
+ * Report the finger status for the @device adding the @added_status flags
+ * and removing the @removed_status flags.
+ *
+ * This can be used by UI to give a feedback
+ *
+ * Returns: %TRUE if changed
+ */
+gboolean
+fpi_device_report_finger_status_changes (FpDevice           *device,
+                                         FpFingerStatusFlags added_status,
+                                         FpFingerStatusFlags removed_status)
+{
+  FpDevicePrivate *priv = fp_device_get_instance_private (device);
+  FpFingerStatusFlags finger_status = priv->finger_status;
+
+  finger_status |= added_status;
+  finger_status &= ~removed_status;
+
+  return fpi_device_report_finger_status (device, finger_status);
+}

libfprint/fpi-device.h

@@ -255,4 +255,10 @@ void fpi_device_identify_report (FpDevice *device,
                                  FpPrint  *print,
                                  GError   *error);
 
+gboolean fpi_device_report_finger_status (FpDevice           *device,
+                                          FpFingerStatusFlags finger_status);
+gboolean fpi_device_report_finger_status_changes (FpDevice           *device,
+                                                  FpFingerStatusFlags added_status,
+                                                  FpFingerStatusFlags removed_status);
+
 G_END_DECLS