/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_NLS_H
#define _LINUX_NLS_H

/* Unicode has changed over the years.  Unicode code points no longer
 * fit into 16 bits; as of Unicode 5 valid code points range from 0
 * to 0x10ffff (17 planes, where each plane holds 65536 code points).
 *
 * The original decision to represent Unicode characters as 16-bit
 * wchar_t values is now outdated.  But plane 0 still includes the
 * most commonly used characters, so we will retain it.  The newer
 * 32-bit unicode_t type can be used when it is necessary to
 * represent the full Unicode character set.
 */

/* Plane-0 Unicode character */
typedef u16 wchar_t;
#define MAX_WCHAR_T	0xffff

/* Arbitrary Unicode character */
typedef u32 unicode_t;

/* this value hold the maximum octet of charset */
#define NLS_MAX_CHARSET_SIZE 6 /* for UTF-8 */

/* Byte order for UTF-16 strings */
enum utf16_endian {
	UTF16_HOST_ENDIAN,
	UTF16_LITTLE_ENDIAN,
	UTF16_BIG_ENDIAN
};

/* nls_base.c */

extern int utf8_to_utf32(const u8 *s, int len, unicode_t *pu);
extern int utf8s_to_utf16s(const u8 *s, int len,
		enum utf16_endian endian, wchar_t *pwcs, int maxlen);

#endif /* _LINUX_NLS_H */