Index: /trunk/src/VBox/Runtime/common/string/base64.h
===================================================================
--- /trunk/src/VBox/Runtime/common/string/base64.h	(revision 84294)
+++ /trunk/src/VBox/Runtime/common/string/base64.h	(revision 84294)
@@ -0,0 +1,83 @@
+/* $Id$ */
+/** @file
+ * IPRT - Base64, MIME content transfer encoding, internal header.
+ */
+
+/*
+ * Copyright (C) 2009-2020 Oracle Corporation
+ *
+ * This file is part of VirtualBox Open Source Edition (OSE), as
+ * available from http://www.virtualbox.org. This file is free software;
+ * you can redistribute it and/or modify it under the terms of the GNU
+ * General Public License (GPL) as published by the Free Software
+ * Foundation, in version 2 as it comes in the "COPYING" file of the
+ * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
+ * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
+ *
+ * The contents of this file may alternatively be used under the terms
+ * of the Common Development and Distribution License Version 1.0
+ * (CDDL) only, as it comes in the "COPYING.CDDL" file of the
+ * VirtualBox OSE distribution, in which case the provisions of the
+ * CDDL are applicable instead of those of the GPL.
+ *
+ * You may elect to license modified versions of this file under the
+ * terms and conditions of either the GPL or the CDDL or both.
+ */
+
+
+/*********************************************************************************************************************************
+*   Defined Constants And Macros                                                                                                 *
+*********************************************************************************************************************************/
+/** The line length used for encoding. */
+#define RTBASE64_LINE_LEN   64
+
+/** @name Special g_au8RTBase64CharToVal values
+ * @{ */
+#define BASE64_SPACE        0xc0
+#define BASE64_PAD          0xe0
+#define BASE64_INVALID      0xff
+/** @} */
+
+
+/*********************************************************************************************************************************
+*   Global Variables                                                                                                             *
+*********************************************************************************************************************************/
+extern DECLHIDDEN(const uint8_t)    g_au8RTBase64CharToVal[256];
+extern DECLHIDDEN(const char)       g_szRTBase64ValToChar[64+1];
+extern DECLHIDDEN(const size_t)     g_acchRTBase64EolStyles[RTBASE64_FLAGS_EOL_STYLE_MASK + 1];
+extern DECLHIDDEN(const char)       g_aachRTBase64EolStyles[RTBASE64_FLAGS_EOL_STYLE_MASK + 1][2];
+
+
+/*********************************************************************************************************************************
+*   Internal Functions                                                                                                           *
+*********************************************************************************************************************************/
+#ifdef RT_STRICT
+DECLHIDDEN(void) rtBase64Sanity(void);
+#endif
+
+
+/**
+ * Recalcs 6-bit to 8-bit and adjust for padding.
+ */
+DECLINLINE(ssize_t) rtBase64DecodedSizeRecalc(uint32_t c6Bits, unsigned cbPad)
+{
+   size_t cb;
+   if (c6Bits * 3 / 3 == c6Bits)
+   {
+       if ((c6Bits * 3 % 4) != 0)
+           return -1;
+       cb = c6Bits * 3 / 4;
+   }
+   else
+   {
+       if ((c6Bits * (uint64_t)3 % 4) != 0)
+           return -1;
+       cb = c6Bits * (uint64_t)3 / 4;
+   }
+
+   if (cb < cbPad)
+       return -1;
+   cb -= cbPad;
+   return cb;
+}
+