usb: gadget: move utf8_to_utf16le to header file

As other users may use utf8_to_utf16le() to convert the utf8
to utf16 for usb, so move it to head file.

Signed-off-by: Li Jun <jun.li@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
This commit is contained in:
Li Jun 2021-01-25 21:43:47 +08:00 committed by Marek Vasut
parent 1c7aacb9a8
commit 6777483f5d
2 changed files with 76 additions and 73 deletions

View file

@ -10,79 +10,7 @@
#include <linux/errno.h>
#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>
#include <asm/unaligned.h>
static int utf8_to_utf16le(const char *s, __le16 *cp, unsigned len)
{
int count = 0;
u8 c;
u16 uchar;
/*
* this insists on correct encodings, though not minimal ones.
* BUT it currently rejects legit 4-byte UTF-8 code points,
* which need surrogate pairs. (Unicode 3.1 can use them.)
*/
while (len != 0 && (c = (u8) *s++) != 0) {
if ((c & 0x80)) {
/*
* 2-byte sequence:
* 00000yyyyyxxxxxx = 110yyyyy 10xxxxxx
*/
if ((c & 0xe0) == 0xc0) {
uchar = (c & 0x1f) << 6;
c = (u8) *s++;
if ((c & 0xc0) != 0x80)
goto fail;
c &= 0x3f;
uchar |= c;
/*
* 3-byte sequence (most CJKV characters):
* zzzzyyyyyyxxxxxx = 1110zzzz 10yyyyyy 10xxxxxx
*/
} else if ((c & 0xf0) == 0xe0) {
uchar = (c & 0x0f) << 12;
c = (u8) *s++;
if ((c & 0xc0) != 0x80)
goto fail;
c &= 0x3f;
uchar |= c << 6;
c = (u8) *s++;
if ((c & 0xc0) != 0x80)
goto fail;
c &= 0x3f;
uchar |= c;
/* no bogus surrogates */
if (0xd800 <= uchar && uchar <= 0xdfff)
goto fail;
/*
* 4-byte sequence (surrogate pairs, currently rare):
* 11101110wwwwzzzzyy + 110111yyyyxxxxxx
* = 11110uuu 10uuzzzz 10yyyyyy 10xxxxxx
* (uuuuu = wwww + 1)
* FIXME accept the surrogate code points (only)
*/
} else
goto fail;
} else
uchar = c;
put_unaligned_le16(uchar, cp++);
count++;
len--;
}
return count;
fail:
return -1;
}
#include <linux/utf.h>
/**
* usb_gadget_get_string - fill out a string descriptor

75
include/linux/utf.h Normal file
View file

@ -0,0 +1,75 @@
#ifndef _LINUX_UTF_H
#define _LINUX_UTF_H
#include <asm/unaligned.h>
static inline int utf8_to_utf16le(const char *s, __le16 *cp, unsigned len)
{
int count = 0;
u8 c;
u16 uchar;
/*
* this insists on correct encodings, though not minimal ones.
* BUT it currently rejects legit 4-byte UTF-8 code points,
* which need surrogate pairs. (Unicode 3.1 can use them.)
*/
while (len != 0 && (c = (u8) *s++) != 0) {
if ((c & 0x80)) {
/*
* 2-byte sequence:
* 00000yyyyyxxxxxx = 110yyyyy 10xxxxxx
*/
if ((c & 0xe0) == 0xc0) {
uchar = (c & 0x1f) << 6;
c = (u8) *s++;
if ((c & 0xc0) != 0x80)
goto fail;
c &= 0x3f;
uchar |= c;
/*
* 3-byte sequence (most CJKV characters):
* zzzzyyyyyyxxxxxx = 1110zzzz 10yyyyyy 10xxxxxx
*/
} else if ((c & 0xf0) == 0xe0) {
uchar = (c & 0x0f) << 12;
c = (u8) *s++;
if ((c & 0xc0) != 0x80)
goto fail;
c &= 0x3f;
uchar |= c << 6;
c = (u8) *s++;
if ((c & 0xc0) != 0x80)
goto fail;
c &= 0x3f;
uchar |= c;
/* no bogus surrogates */
if (0xd800 <= uchar && uchar <= 0xdfff)
goto fail;
/*
* 4-byte sequence (surrogate pairs, currently rare):
* 11101110wwwwzzzzyy + 110111yyyyxxxxxx
* = 11110uuu 10uuzzzz 10yyyyyy 10xxxxxx
* (uuuuu = wwww + 1)
* FIXME accept the surrogate code points (only)
*/
} else
goto fail;
} else
uchar = c;
put_unaligned_le16(uchar, cp++);
count++;
len--;
}
return count;
fail:
return -1;
}
#endif /* _LINUX_UTF_H */