examples: Make possible to select the finger to enroll/verify

Move some common functions to an utilities file.

examples/enroll.c

@@ -1,6 +1,6 @@
 /*
  * Example fingerprint enrollment program
- * Enrolls your right index finger and saves the print to disk
+ * Enrolls your choosen finger and saves the print to disk
  * Copyright (C) 2007 Daniel Drake <dsd@gentoo.org>
  * Copyright (C) 2019 Marco Trevisan <marco.trevisan@canonical.com>
  *
@@ -23,10 +23,12 @@
 #include <libfprint/fprint.h>
 
 #include "storage.h"
+#include "utilities.h"
 
 typedef struct _EnrollData
 {
   GMainLoop *loop;
+  FpFinger   finger;
   int        ret_value;
 } EnrollData;
 
@@ -82,7 +84,7 @@ on_enroll_completed (FpDevice *dev, GAsyncResult *res, void *user_data)
       if (!fp_device_has_storage (dev))
         {
           g_debug ("Device has not storage, saving locally");
-          int r = print_data_save (print, FP_FINGER_RIGHT_INDEX);
+          int r = print_data_save (print, enroll_data->finger);
           if (r < 0)
             {
               g_warning ("Data save failed, code %d", r);
@@ -139,11 +141,12 @@ on_device_opened (FpDevice *dev, GAsyncResult *res, void *user_data)
     }
 
   printf ("Opened device. It's now time to enroll your finger.\n\n");
-  printf ("You will need to successfully scan your finger %d times to "
+  printf ("You will need to successfully scan your %s finger %d times to "
-          "complete the process.\n\n", fp_device_get_nr_enroll_stages (dev));
+          "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, FP_FINGER_RIGHT_INDEX);
+  print_template = print_create_template (dev, enroll_data->finger);
   fp_device_enroll (dev, print_template, NULL, on_enroll_progress, NULL,
                     NULL, (GAsyncReadyCallback) on_enroll_completed,
                     enroll_data);
@@ -156,13 +159,23 @@ main (void)
   g_autoptr(EnrollData) enroll_data = NULL;
   GPtrArray *devices;
   FpDevice *dev;
+  FpFinger finger;
 
-  printf ("This program will enroll your right index finger, "
+  g_print ("This program will enroll the selected finger, unconditionally "
-          "unconditionally overwriting any right-index print that was enrolled "
+           "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 ("Choose the finger to enroll:\n");
+  finger = finger_chooser ();
+
+  if (finger == FP_FINGER_UNKNOWN)
+    {
+      g_warning ("Unknown finger selected");
+      return EXIT_FAILURE;
+    }
+
   setenv ("G_MESSAGES_DEBUG", "all", 0);
 
   ctx = fp_context_new ();
@@ -182,6 +195,7 @@ main (void)
     }
 
   enroll_data = g_new0 (EnrollData, 1);
+  enroll_data->finger = finger;
   enroll_data->ret_value = EXIT_FAILURE;
   enroll_data->loop = g_main_loop_new (NULL, FALSE);
 

examples/manage-prints.c

@@ -21,6 +21,7 @@
 #include <stdio.h>
 
 #include <libfprint/fprint.h>
+#include "utilities.h"
 
 typedef struct _ListData
 {
@@ -68,46 +69,6 @@ on_device_closed (FpDevice     *dev,
   g_main_loop_quit (list_data->loop);
 }
 
-const char *
-finger_to_string (FpFinger finger)
-{
-  switch (finger)
-    {
-    case FP_FINGER_LEFT_THUMB:
-      return "left thumb";
-
-    case FP_FINGER_LEFT_INDEX:
-      return "left index";
-
-    case FP_FINGER_LEFT_MIDDLE:
-      return "left middle";
-
-    case FP_FINGER_LEFT_RING:
-      return "left ring";
-
-    case FP_FINGER_LEFT_LITTLE:
-      return "left little";
-
-    case FP_FINGER_RIGHT_THUMB:
-      return "right thumb";
-
-    case FP_FINGER_RIGHT_INDEX:
-      return "right index";
-
-    case FP_FINGER_RIGHT_MIDDLE:
-      return "right middle";
-
-    case FP_FINGER_RIGHT_RING:
-      return "right ring";
-
-    case FP_FINGER_RIGHT_LITTLE:
-      return "right little";
-
-    default:
-      return "unknown";
-    }
-}
-
 typedef struct _DeleteData
 {
   ListData *list_data;
@@ -218,7 +179,7 @@ on_list_completed (FpDevice     *dev,
         {
           gint64 idx = 0;
 
-          g_print ("Want to delete saved print? [<number>/A/n]\n");
+          g_print ("Want to delete saved print? [<number>/A/n]\n> ");
           if (fgets (buf, 3, stdin))
             idx = g_ascii_strtoll (buf, NULL, 10);
 

examples/meson.build

@@ -2,7 +2,7 @@
 examples = [ 'enroll', 'verify', 'manage-prints' ]
 foreach example: examples
     executable(example,
-               [example + '.c', 'storage.c'],
+               [example + '.c', 'storage.c', 'utilities.c'],
                dependencies: [libfprint_dep, glib_dep],
                include_directories: [
                  root_inc,

examples/utilities.c

@@ -0,0 +1,94 @@
+/*
+ * Utilities for example programs
+ *
+ * Copyright (C) 2019 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 <libfprint/fprint.h>
+#include <stdio.h>
+
+#include "utilities.h"
+
+const char *
+finger_to_string (FpFinger finger)
+{
+  switch (finger)
+    {
+    case FP_FINGER_LEFT_THUMB:
+      return "left thumb";
+
+    case FP_FINGER_LEFT_INDEX:
+      return "left index";
+
+    case FP_FINGER_LEFT_MIDDLE:
+      return "left middle";
+
+    case FP_FINGER_LEFT_RING:
+      return "left ring";
+
+    case FP_FINGER_LEFT_LITTLE:
+      return "left little";
+
+    case FP_FINGER_RIGHT_THUMB:
+      return "right thumb";
+
+    case FP_FINGER_RIGHT_INDEX:
+      return "right index";
+
+    case FP_FINGER_RIGHT_MIDDLE:
+      return "right middle";
+
+    case FP_FINGER_RIGHT_RING:
+      return "right ring";
+
+    case FP_FINGER_RIGHT_LITTLE:
+      return "right little";
+
+    default:
+      return "unknown";
+    }
+}
+
+FpFinger
+finger_chooser (void)
+{
+  int i;
+  const FpFinger all_fingers[] = {
+    FP_FINGER_LEFT_THUMB,
+    FP_FINGER_LEFT_INDEX,
+    FP_FINGER_LEFT_MIDDLE,
+    FP_FINGER_LEFT_RING,
+    FP_FINGER_LEFT_LITTLE,
+    FP_FINGER_RIGHT_THUMB,
+    FP_FINGER_RIGHT_INDEX,
+    FP_FINGER_RIGHT_MIDDLE,
+    FP_FINGER_RIGHT_RING,
+    FP_FINGER_RIGHT_LITTLE,
+  };
+
+  for (i = all_fingers[0]; i <= G_N_ELEMENTS (all_fingers); ++i)
+    g_print("  [%d] %s\n", (i - all_fingers[0]), finger_to_string (i));
+
+  g_print ("> ");
+  if (!scanf ("%d%*c", &i))
+    return FP_FINGER_UNKNOWN;
+
+  if (i < 0 || i >= G_N_ELEMENTS (all_fingers))
+    return FP_FINGER_UNKNOWN;
+
+  return all_fingers[i];
+}

examples/utilities.h

@@ -0,0 +1,27 @@
+/*
+ * Trivial storage driver for example programs
+ *
+ * Copyright (C) 2019 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
+ */
+
+#ifndef __UTILITIES_H
+#define __UTILITIES_H
+
+FpFinger finger_chooser (void);
+const char * finger_to_string (FpFinger finger);
+
+#endif /* __UTILITIES_H */

examples/verify.c

@@ -1,5 +1,5 @@
 /*
- * Example fingerprint verification program, which verifies the right index
+ * Example fingerprint verification program, which verifies the
  * finger which has been previously enrolled to disk.
  * Copyright (C) 2007 Daniel Drake <dsd@gentoo.org>
  * Copyright (C) 2019 Marco Trevisan <marco.trevisan@canonical.com>
@@ -23,10 +23,12 @@
 #include <libfprint/fprint.h>
 
 #include "storage.h"
+#include "utilities.h"
 
 typedef struct _VerifyData
 {
   GMainLoop *loop;
+  FpFinger   finger;
   int        ret_value;
 } VerifyData;
 
@@ -134,7 +136,7 @@ on_list_completed (FpDevice *dev, GAsyncResult *res, gpointer user_data)
         {
           FpPrint *print = prints->pdata[i];
 
-          if (fp_print_get_finger (print) == FP_FINGER_RIGHT_INDEX &&
+          if (fp_print_get_finger (print) == verify_data->finger &&
               g_strcmp0 (fp_print_get_username (print), g_get_user_name ()) == 0)
             {
               if (!verify_print ||
@@ -146,8 +148,8 @@ on_list_completed (FpDevice *dev, GAsyncResult *res, gpointer user_data)
 
       if (!verify_print)
         {
-          g_warning ("Did you remember to enroll your right index "
+          g_warning ("Did you remember to enroll your %s finger first?",
-                     "finger first?");
+                     finger_to_string (verify_data->finger));
           g_main_loop_quit (verify_data->loop);
           return;
         }
@@ -170,6 +172,17 @@ on_list_completed (FpDevice *dev, GAsyncResult *res, gpointer user_data)
 static void
 start_verification (FpDevice *dev, VerifyData *verify_data)
 {
+  g_print ("Choose the finger to verify:\n");
+  verify_data->finger = finger_chooser ();
+
+  if (verify_data->finger == FP_FINGER_UNKNOWN)
+    {
+      g_warning ("Unknown finger selected");
+      verify_data->ret_value = EXIT_FAILURE;
+      g_main_loop_quit (verify_data->loop);
+      return;
+    }
+
   if (fp_device_has_storage (dev))
     {
       g_print ("Creating finger template, using device storage...\n");
@@ -179,16 +192,17 @@ start_verification (FpDevice *dev, VerifyData *verify_data)
     }
   else
     {
-      g_print ("Loading previously enrolled right index finger data...\n");
+      g_print ("Loading previously enrolled %s finger data...\n",
+               finger_to_string (verify_data->finger));
       g_autoptr(FpPrint) verify_print;
 
-      verify_print = print_data_load (dev, FP_FINGER_RIGHT_INDEX);
+      verify_print = print_data_load (dev, verify_data->finger);
 
       if (!verify_print)
         {
           g_warning ("Failed to load fingerprint data");
-          g_warning ("Did you remember to enroll your right index "
+          g_warning ("Did you remember to enroll your %s finger first?",
-                     "finger first?");
+                     finger_to_string (verify_data->finger));
           g_main_loop_quit (verify_data->loop);
           return;
         }