u-boot/include/charset.h
AKASHI Takahiro f8062c963a lib: charset: add u16_str<n>cmp()
u16 version of strcmp(): u16_strncmp() works like u16_strcmp() but only
at most n characters (in u16) are compared.
This function will be used in my UEFI secure boot patch.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2019-09-20 20:09:19 +02:00

250 lines
7.2 KiB
C

/* SPDX-License-Identifier: GPL-2.0+ */
/*
* charset conversion utils
*
* Copyright (c) 2017 Rob Clark
*/
#ifndef __CHARSET_H_
#define __CHARSET_H_
#include <linux/kernel.h>
#include <linux/types.h>
#define MAX_UTF8_PER_UTF16 3
/**
* console_read_unicode() - read Unicode code point from console
*
* @code: pointer to store Unicode code point
* Return: 0 = success
*/
int console_read_unicode(s32 *code);
/**
* utf8_get() - get next UTF-8 code point from buffer
*
* @src: pointer to current byte, updated to point to next byte
* Return: code point, or 0 for end of string, or -1 if no legal
* code point is found. In case of an error src points to
* the incorrect byte.
*/
s32 utf8_get(const char **src);
/**
* utf8_put() - write UTF-8 code point to buffer
*
* @code: code point
* @dst: pointer to destination buffer, updated to next position
* Return: -1 if the input parameters are invalid
*/
int utf8_put(s32 code, char **dst);
/**
* utf8_utf16_strnlen() - length of a truncated utf-8 string after conversion
* to utf-16
*
* @src: utf-8 string
* @count: maximum number of code points to convert
* Return: length in u16 after conversion to utf-16 without the
* trailing \0. If an invalid UTF-8 sequence is hit one
* u16 will be reserved for a replacement character.
*/
size_t utf8_utf16_strnlen(const char *src, size_t count);
/**
* utf8_utf16_strlen() - length of a utf-8 string after conversion to utf-16
*
* @src: utf-8 string
* Return: length in u16 after conversion to utf-16 without the
* trailing \0. If an invalid UTF-8 sequence is hit one
* u16 will be reserved for a replacement character.
*/
#define utf8_utf16_strlen(a) utf8_utf16_strnlen((a), SIZE_MAX)
/**
* utf8_utf16_strncpy() - copy utf-8 string to utf-16 string
*
* @dst: destination buffer
* @src: source buffer
* @count: maximum number of code points to copy
* Return: -1 if the input parameters are invalid
*/
int utf8_utf16_strncpy(u16 **dst, const char *src, size_t count);
/**
* utf8_utf16_strcpy() - copy utf-8 string to utf-16 string
*
* @dst: destination buffer
* @src: source buffer
* Return: -1 if the input parameters are invalid
*/
#define utf8_utf16_strcpy(d, s) utf8_utf16_strncpy((d), (s), SIZE_MAX)
/**
* utf16_get() - get next UTF-16 code point from buffer
*
* @src: pointer to current word, updated to point to next word
* Return: code point, or 0 for end of string, or -1 if no legal
* code point is found. In case of an error src points to
* the incorrect word.
*/
s32 utf16_get(const u16 **src);
/**
* utf16_put() - write UTF-16 code point to buffer
*
* @code: code point
* @dst: pointer to destination buffer, updated to next position
* Return: -1 if the input parameters are invalid
*/
int utf16_put(s32 code, u16 **dst);
/**
* utf16_strnlen() - length of a truncated utf-16 string
*
* @src: utf-16 string
* @count: maximum number of code points to convert
* Return: length in code points. If an invalid UTF-16 sequence is
* hit one position will be reserved for a replacement
* character.
*/
size_t utf16_strnlen(const u16 *src, size_t count);
/**
* utf16_utf8_strnlen() - length of a truncated utf-16 string after conversion
* to utf-8
*
* @src: utf-16 string
* @count: maximum number of code points to convert
* Return: length in bytes after conversion to utf-8 without the
* trailing \0. If an invalid UTF-16 sequence is hit one
* byte will be reserved for a replacement character.
*/
size_t utf16_utf8_strnlen(const u16 *src, size_t count);
/**
* utf16_utf8_strlen() - length of a utf-16 string after conversion to utf-8
*
* @src: utf-16 string
* Return: length in bytes after conversion to utf-8 without the
* trailing \0. If an invalid UTF-16 sequence is hit one
* byte will be reserved for a replacement character.
*/
#define utf16_utf8_strlen(a) utf16_utf8_strnlen((a), SIZE_MAX)
/**
* utf16_utf8_strncpy() - copy utf-16 string to utf-8 string
*
* @dst: destination buffer
* @src: source buffer
* @count: maximum number of code points to copy
* Return: -1 if the input parameters are invalid
*/
int utf16_utf8_strncpy(char **dst, const u16 *src, size_t count);
/**
* utf16_utf8_strcpy() - copy utf-16 string to utf-8 string
*
* @dst: destination buffer
* @src: source buffer
* Return: -1 if the input parameters are invalid
*/
#define utf16_utf8_strcpy(d, s) utf16_utf8_strncpy((d), (s), SIZE_MAX)
/**
* utf_to_lower() - convert a Unicode letter to lower case
*
* @code: letter to convert
* Return: lower case letter or unchanged letter
*/
s32 utf_to_lower(const s32 code);
/**
* utf_to_upper() - convert a Unicode letter to upper case
*
* @code: letter to convert
* Return: upper case letter or unchanged letter
*/
s32 utf_to_upper(const s32 code);
/*
* u16_strncmp() - compare two u16 string
*
* @s1: first string to compare
* @s2: second string to compare
* @n: maximum number of u16 to compare
* Return: 0 if the first n u16 are the same in s1 and s2
* < 0 if the first different u16 in s1 is less than the
* corresponding u16 in s2
* > 0 if the first different u16 in s1 is greater than the
* corresponding u16 in s2
*/
int u16_strncmp(const u16 *s1, const u16 *s2, size_t n);
#define u16_strcmp(s1, s2) u16_strncmp((s1), (s2), SIZE_MAX)
/**
* u16_strlen - count non-zero words
*
* This function matches wsclen() if the -fshort-wchar compiler flag is set.
* In the EFI context we explicitly need a function handling u16 strings.
*
* @in: null terminated u16 string
* ReturnValue: number of non-zero words.
* This is not the number of utf-16 letters!
*/
size_t u16_strlen(const void *in);
/**
* u16_strlen - count non-zero words
*
* This function matches wscnlen_s() if the -fshort-wchar compiler flag is set.
* In the EFI context we explicitly need a function handling u16 strings.
*
* @in: null terminated u16 string
* @count: maximum number of words to count
* ReturnValue: number of non-zero words.
* This is not the number of utf-16 letters!
*/
size_t u16_strnlen(const u16 *in, size_t count);
/**
* u16_strcpy() - copy u16 string
*
* Copy u16 string pointed to by src, including terminating null word, to
* the buffer pointed to by dest.
*
* @dest: destination buffer
* @src: source buffer (null terminated)
* Return: 'dest' address
*/
u16 *u16_strcpy(u16 *dest, const u16 *src);
/**
* u16_strdup() - duplicate u16 string
*
* Copy u16 string pointed to by src, including terminating null word, to a
* newly allocated buffer.
*
* @src: source buffer (null terminated)
* Return: allocated new buffer on success, NULL on failure
*/
u16 *u16_strdup(const void *src);
/**
* utf16_to_utf8() - Convert an utf16 string to utf8
*
* Converts 'size' characters of the utf16 string 'src' to utf8
* written to the 'dest' buffer.
*
* NOTE that a single utf16 character can generate up to 3 utf8
* characters. See MAX_UTF8_PER_UTF16.
*
* @dest the destination buffer to write the utf8 characters
* @src the source utf16 string
* @size the number of utf16 characters to convert
* @return the pointer to the first unwritten byte in 'dest'
*/
uint8_t *utf16_to_utf8(uint8_t *dest, const uint16_t *src, size_t size);
#endif /* __CHARSET_H_ */