type conversion gdouble<->guint64 is not supported in all MSVC versions, convert it with functions

svn path=/trunk/; revision=27032

1 files changed, 70 insertions, 0 deletions

diff --git a/wsutil/type_util.c b/wsutil/type_util.c
new file mode 100644
index 0000000000..e90575d7ba
--- /dev/null
+++ b/wsutil/type_util.c
@@ -0,0 +1,70 @@
+/* type_util.c
+ * Types utility routines
+ *
+ * $Id$
+ *
+ * Wireshark - Network traffic analyzer
+ * By Gerald Combs <gerald@wireshark.org>
+ * Copyright 1998 Gerald Combs
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include <glib.h>
+#include "type_util.h"
+
+/*
+ * guint64 to gdouble conversions taken from gstutils.c of GStreamer project
+ *
+ * GStreamer
+ * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
+ *                    2000 Wim Taymans <wtay@chello.be>
+ *                    2002 Thomas Vander Stichele <thomas@apestaart.org>
+ *
+ * gstutils.h: Header for various utility functions
+ *
+ * GNU GPL v2
+ * 
+ */
+
+/* work around error C2520: conversion from unsigned __int64 to double
+ * not implemented, use signed __int64
+ *
+ * These are implemented as functions because on some platforms a 64bit int to
+ * double conversion is not defined/implemented.
+ */
+
+gdouble
+type_util_guint64_to_gdouble(guint64 value)
+{
+  if (value & G_GINT64_CONSTANT (0x8000000000000000))
+    return (gdouble) ((gint64) value) + (gdouble) 18446744073709551616.;
+  else
+    return (gdouble) ((gint64) value);
+}
+
+guint64
+type_util_gdouble_to_guint64(gdouble value)
+{
+  if (value < (gdouble) 9223372036854775808.)   /* 1 << 63 */
+    return ((guint64) ((gint64) value));
+
+  value -= (gdouble) 18446744073709551616.;
+  return ((guint64) ((gint64) value));
+}