linux/fs/unicode/utf8n.h
Christoph Hellwig 6ca99ce756 unicode: cache the normalization tables in struct unicode_map
Instead of repeatedly looking up the version add pointers to the
NFD and NFD+CF tables to struct unicode_map, and pass a
unicode_map plus index to the functions using the normalization
tables.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
2021-10-11 17:02:02 -03:00

82 lines
2.1 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (c) 2014 SGI.
* All rights reserved.
*/
#ifndef UTF8NORM_H
#define UTF8NORM_H
#include <linux/types.h>
#include <linux/export.h>
#include <linux/string.h>
#include <linux/module.h>
#include <linux/unicode.h>
int utf8version_is_supported(unsigned int version);
/*
* Look for the correct const struct utf8data for a unicode version.
* Returns NULL if the version requested is too new.
*
* Two normalization forms are supported: nfdi and nfdicf.
*
* nfdi:
* - Apply unicode normalization form NFD.
* - Remove any Default_Ignorable_Code_Point.
*
* nfdicf:
* - Apply unicode normalization form NFD.
* - Remove any Default_Ignorable_Code_Point.
* - Apply a full casefold (C + F).
*/
extern const struct utf8data *utf8nfdi(unsigned int maxage);
extern const struct utf8data *utf8nfdicf(unsigned int maxage);
/*
* Determine the length of the normalized from of the string,
* excluding any terminating NULL byte.
* Returns 0 if only ignorable code points are present.
* Returns -1 if the input is not valid UTF-8.
*/
ssize_t utf8nlen(const struct unicode_map *um, enum utf8_normalization n,
const char *s, size_t len);
/* Needed in struct utf8cursor below. */
#define UTF8HANGULLEAF (12)
/*
* Cursor structure used by the normalizer.
*/
struct utf8cursor {
const struct unicode_map *um;
enum utf8_normalization n;
const char *s;
const char *p;
const char *ss;
const char *sp;
unsigned int len;
unsigned int slen;
short int ccc;
short int nccc;
unsigned char hangul[UTF8HANGULLEAF];
};
/*
* Initialize a utf8cursor to normalize a string.
* Returns 0 on success.
* Returns -1 on failure.
*/
int utf8ncursor(struct utf8cursor *u8c, const struct unicode_map *um,
enum utf8_normalization n, const char *s, size_t len);
/*
* Get the next byte in the normalization.
* Returns a value > 0 && < 256 on success.
* Returns 0 when the end of the normalization is reached.
* Returns -1 if the string being normalized is not valid UTF-8.
*/
extern int utf8byte(struct utf8cursor *u8c);
#endif /* UTF8NORM_H */