scanadf,xcam: remove atexit macro and call exit functions manually.

sane_exit() *must* be called on exit in every occasion otherwise there
will be crashes from the cleanup of backends. Since on_exit() is not
bound to be supported, we cannot rely on it being available.
So the applications must ensure that the sane_exit() function is always
called on all exit routes to avoid crashing at the end of session.

configure.in

@@ -96,7 +96,7 @@ fi
 dnl Checks for library functions.
 AC_FUNC_ALLOCA
 AC_FUNC_MMAP
-AC_CHECK_FUNCS(atexit mkdir sigprocmask strdup strndup strftime strstr \
+AC_CHECK_FUNCS(mkdir sigprocmask strdup strndup strftime strstr \
   strsep strtod snprintf usleep strcasecmp strncasecmp getenv isfdtype vsyslog)
 
 if test "$ac_cv_header_os2_h" = "yes" ; then

src/scanadf.c

@@ -100,11 +100,6 @@ sane_strframe (SANE_Frame f)
   (f) == SANE_FRAME_GREEN || \
   (f) == SANE_FRAME_BLUE )
 
-
-#ifndef HAVE_ATEXIT
-# define atexit(func)	on_exit(func, 0)	/* works for SunOS, at least */
-#endif
-
 typedef struct
   {
     u_char *data;
@@ -1419,8 +1414,6 @@ main (int argc, char **argv)
   int startNum = 1, endNum = -1;		/* start/end numbers of pages to scan */
   int no_overwrite = 0;
 
-  atexit (sane_exit);
-
   prog_name = strrchr (argv[0], '/');
   if (prog_name)
     ++prog_name;
@@ -1477,7 +1470,7 @@ main (int argc, char **argv)
 
 	case 'V':
 	  printf ("scanadf (%s) %s\n", PACKAGE, VERSION);
-	  exit (0);
+	  scanadf_exit (0);
 
 	default:
 	  break;	/* ignore device specific options for now */
@@ -1721,5 +1714,5 @@ List of available devices:", prog_name);
   if (scriptWait)
     while (wait(NULL) != -1);
 
-  return (status == SANE_STATUS_GOOD) ? 0 : 1;
+  scanadf_exit((status == SANE_STATUS_GOOD) ? 0 : 1);
 }

src/xcam.c

@@ -65,10 +65,6 @@
 
 #define MAX_LUM		64	/* how many graylevels for 8 bit displays */
 
-#ifndef HAVE_ATEXIT
-# define atexit(func)	on_exit(func, 0)	/* works for SunOS, at least */
-#endif
-
 typedef struct Canvas
 {
   GtkWidget *preview;
@@ -158,6 +154,8 @@ static void update_param (GSGDialog * dialog, void *arg);
 
 static void load_defaults (int silent);
 
+static void xcam_exit (void);
+
 static struct option long_options[] = {
   {"help", no_argument, NULL, 'h'},
   {"version", no_argument, NULL, 'V'},
@@ -684,7 +682,8 @@ exit_callback (GtkWidget * widget, gpointer data)
   if (dialog)
     gsg_destroy_dialog (dialog);
   dialog = 0;
-  exit (0);
+  xcam_exit ();
+  exit(0);
 }
 
 static void
@@ -810,7 +809,8 @@ build_device_menu (void)
   if (status != SANE_STATUS_GOOD)
     {
       fprintf (stderr, "%s: %s\n", prog_name, sane_strstatus (status));
-      exit (1);
+      xcam_exit();
+      exit(1);
     }
 
   for (i = 0; device[i]; ++i)
@@ -1669,7 +1669,8 @@ main (int argc, char **argv)
     {
       DBG (DBG_fatal, "init: sane_main failed: %s\n",
 	   sane_strstatus (status));
-      exit (1);
+      xcam_exit();
+      exit(1);
     }
 
   if (argc > 1)
@@ -1681,15 +1682,18 @@ main (int argc, char **argv)
 	    {
 	    case 'V':
 	      printf ("xcam (%s) %s\n", PACKAGE, VERSION);
-	      exit (0);
+	      xcam_exit();
+	      exit(0);
 
 	    case 'B':
 	      win.buf_backend_size = 1024 * 1024;
 	      break;
+
 	    case 'h':
 	    default:
 	      usage ();
-	      exit (0);
+	      xcam_exit();
+	      exit(0);
 	    }
 	}
     }
@@ -1702,8 +1706,6 @@ main (int argc, char **argv)
   gdk_set_show_events (0);
   gtk_init (&argc, &argv);
 
-  atexit (xcam_exit);
-
   win.gdk_input_tag = -1;
   win.shell = gtk_window_new (GTK_WINDOW_TOPLEVEL);
   gtk_window_set_title (GTK_WINDOW (win.shell), (char *) prog_name);
@@ -1813,7 +1815,8 @@ main (int argc, char **argv)
 	   "          detected by sane-find-scanner (if appropriate). Please read\n"
 	   "          the documentation which came with this software (README, FAQ,\n"
 	   "          manpages).\n");
-      atexit (xcam_exit);
+      xcam_exit();
+      exit(1);
     }
 
   if (dialog && gsg_dialog_get_device (dialog)
@@ -1938,5 +1941,6 @@ main (int argc, char **argv)
   pref_xcam_save ();
 
   DBG (DBG_debug, "xcam main exit\n");
+  xcam_exit();
   return 0;
 }