proxmark3/client/tinycbor/utf8_p.h
2019-03-10 11:20:22 +01:00

103 lines
2.9 KiB
C

/****************************************************************************
**
** Copyright (C) 2017 Intel Corporation
**
** Permission is hereby granted, free of charge, to any person obtaining a copy
** of this software and associated documentation files (the "Software"), to deal
** in the Software without restriction, including without limitation the rights
** to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
** copies of the Software, and to permit persons to whom the Software is
** furnished to do so, subject to the following conditions:
**
** The above copyright notice and this permission notice shall be included in
** all copies or substantial portions of the Software.
**
** THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
** IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
** FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
** AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
** LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
** OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
** THE SOFTWARE.
**
****************************************************************************/
#ifndef CBOR_UTF8_H
#define CBOR_UTF8_H
#include "compilersupport_p.h"
#include <stdint.h>
static inline uint32_t get_utf8(const uint8_t **buffer, const uint8_t *end) {
int charsNeeded;
uint32_t uc, min_uc;
uint8_t b;
ptrdiff_t n = end - *buffer;
if (n == 0)
return ~0U;
uc = *(*buffer)++;
if (uc < 0x80) {
/* single-byte UTF-8 */
return uc;
}
/* multi-byte UTF-8, decode it */
if (unlikely(uc <= 0xC1))
return ~0U;
if (uc < 0xE0) {
/* two-byte UTF-8 */
charsNeeded = 2;
min_uc = 0x80;
uc &= 0x1f;
} else if (uc < 0xF0) {
/* three-byte UTF-8 */
charsNeeded = 3;
min_uc = 0x800;
uc &= 0x0f;
} else if (uc < 0xF5) {
/* four-byte UTF-8 */
charsNeeded = 4;
min_uc = 0x10000;
uc &= 0x07;
} else {
return ~0U;
}
if (n < charsNeeded)
return ~0U;
/* first continuation character */
b = *(*buffer)++;
if ((b & 0xc0) != 0x80)
return ~0U;
uc <<= 6;
uc |= b & 0x3f;
if (charsNeeded > 2) {
/* second continuation character */
b = *(*buffer)++;
if ((b & 0xc0) != 0x80)
return ~0U;
uc <<= 6;
uc |= b & 0x3f;
if (charsNeeded > 3) {
/* third continuation character */
b = *(*buffer)++;
if ((b & 0xc0) != 0x80)
return ~0U;
uc <<= 6;
uc |= b & 0x3f;
}
}
/* overlong sequence? surrogate pair? out or range? */
if (uc < min_uc || uc - 0xd800U < 2048U || uc > 0x10ffff)
return ~0U;
return uc;
}
#endif /* CBOR_UTF8_H */