/* GTK - The GIMP Toolkit
 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

/*
 * Modified by the GTK+ Team and others 1997-1999.  See the AUTHORS
 * file for a list of people on the GTK+ Team.  See the ChangeLog
 * files for a list of changes.  These files are distributed with
 * GTK+ at ftp://ftp.gtk.org/pub/gtk/. 
 */

/* collect a single argument value from a va_list.
 * this is implemented as a huge macro <shrug>, because we can't
 * pass va_list variables by reference on some systems.
 * the corresponding prototype would be:
 * static inline gchar*
 * gtk_arg_collect_value (GtkArg  *arg,
 *		          va_list  var_args);
 */
#define	GTK_ARG_COLLECT_VALUE(arg, var_args, _error)	\
G_STMT_START { \
  gchar *error_msg; \
  GtkType fundamental_type; \
  \
  fundamental_type = GTK_FUNDAMENTAL_TYPE (arg->type); \
  \
  error_msg = NULL; \
  switch (fundamental_type) \
    { \
    case GTK_TYPE_INVALID: \
      error_msg = g_strdup ("invalid untyped argument"); \
      break; \
 \
    case GTK_TYPE_NONE: \
      /* we just ignore this type, since it arithmetically just requires \
       * us to not move the var_args pointer any further. callers need to \
       * check for the validity of GTK_TYPE_NONE themselves. \
       * \
       * error_msg = g_strdup ("invalid argument type `void'"); \
       */ \
      break; \
 \
      /* everything smaller than an int is guarranteed to be \
       * passed as an int \
       */ \
    case GTK_TYPE_CHAR: \
      GTK_VALUE_CHAR (*arg) = va_arg (var_args, gint); \
      break; \
    case GTK_TYPE_UCHAR: \
      GTK_VALUE_UCHAR (*arg) = va_arg (var_args, guint); \
      break; \
    case GTK_TYPE_BOOL: \
      GTK_VALUE_BOOL (*arg) = va_arg (var_args, gint); \
      break; \
    case GTK_TYPE_INT: \
      GTK_VALUE_INT (*arg) = va_arg (var_args, gint); \
      break; \
    case GTK_TYPE_UINT: \
      GTK_VALUE_UINT (*arg) = va_arg (var_args, guint); \
      break; \
    case GTK_TYPE_ENUM: \
      GTK_VALUE_ENUM (*arg) = va_arg (var_args, gint); \
      break; \
    case GTK_TYPE_FLAGS: \
      GTK_VALUE_FLAGS (*arg) = va_arg (var_args, guint); \
      break; \
 \
      /* we collect longs as glongs since they differ in size with \
       * integers on some platforms \
       */ \
    case GTK_TYPE_LONG: \
      GTK_VALUE_LONG (*arg) = va_arg (var_args, glong); \
      break; \
    case GTK_TYPE_ULONG: \
      GTK_VALUE_ULONG (*arg) = va_arg (var_args, gulong); \
      break; \
 \
      /* floats are always passed as doubles \
       */ \
    case GTK_TYPE_FLOAT: \
      /* GTK_VALUE_FLOAT (*arg) = va_arg (var_args, gfloat); */ \
      GTK_VALUE_FLOAT (*arg) = va_arg (var_args, gdouble); \
      break; \
    case GTK_TYPE_DOUBLE: \
      GTK_VALUE_DOUBLE (*arg) = va_arg (var_args, gdouble); \
      break; \
 \
      /* collect pointer values \
       */ \
    case GTK_TYPE_STRING: \
      GTK_VALUE_STRING (*arg) = va_arg (var_args, gchar*); \
      break; \
    case GTK_TYPE_POINTER: \
      GTK_VALUE_POINTER (*arg) = va_arg (var_args, gpointer); \
      break; \
    case GTK_TYPE_BOXED: \
      GTK_VALUE_BOXED (*arg) = va_arg (var_args, gpointer); \
      break; \
 \
      /* structured types \
       */ \
    case GTK_TYPE_SIGNAL: \
      GTK_VALUE_SIGNAL (*arg).f = va_arg (var_args, GtkSignalFunc); \
      GTK_VALUE_SIGNAL (*arg).d = va_arg (var_args, gpointer); \
      break; \
 \
      /* we do some extra sanity checking when collecting objects, \
       * i.e. if the object pointer is not NULL, we check whether we \
       * actually got an object pointer within the desired class branch. \
       */ \
    case G_TYPE_OBJECT: \
      GTK_VALUE_OBJECT (*arg) = va_arg (var_args, GtkObject*); \
      if (GTK_VALUE_OBJECT (*arg) != NULL) \
	{ \
	  register GtkObject *object = GTK_VALUE_OBJECT (*arg); \
	   \
	  if (((GTypeInstance*) object)->g_class == NULL) \
	    error_msg = g_strconcat ("invalid unclassed object pointer for argument type `", \
				     gtk_type_name (arg->type), \
				     "'", \
				     NULL); \
	  else if (!gtk_type_is_a (GTK_OBJECT_TYPE (object), arg->type)) \
	    error_msg = g_strconcat ("invalid object `", \
				     gtk_type_name (G_OBJECT_TYPE (object)), \
				     "' for argument type `", \
				     gtk_type_name (arg->type), \
				     "'", \
				     NULL); \
	} \
      break; \
 \
    default: \
      error_msg = g_strconcat ("unsupported argument type `", \
			       gtk_type_name (arg->type), \
			       "'", \
			       NULL); \
      break; \
    } \
   \
  _error = error_msg; /* return error_msg; */ \
} G_STMT_END