1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2013 Ed Schouten <ed@FreeBSD.org>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #include <uchar.h>
30 #include "mblocal.h"
31
32 typedef struct {
33 char16_t trail_surrogate;
34 mbstate_t c32_mbstate;
35 } _Char16State;
36
37 size_t
mbrtoc16_l(char16_t * __restrict pc16,const char * __restrict s,size_t n,mbstate_t * __restrict ps,locale_t locale)38 mbrtoc16_l(char16_t * __restrict pc16, const char * __restrict s, size_t n,
39 mbstate_t * __restrict ps, locale_t locale)
40 {
41 _Char16State *cs;
42 char32_t c32;
43 ssize_t len;
44
45 FIX_LOCALE(locale);
46 if (ps == NULL)
47 ps = &(XLOCALE_CTYPE(locale)->mbrtoc16);
48 cs = (_Char16State *)ps;
49
50 /*
51 * Call straight into mbrtoc32_l() if we don't need to return a
52 * character value. According to the spec, if s is a null
53 * pointer, the value of parameter pc16 is also ignored.
54 */
55 if (pc16 == NULL || s == NULL) {
56 cs->trail_surrogate = 0;
57 return (mbrtoc32_l(NULL, s, n, &cs->c32_mbstate, locale));
58 }
59
60 /* Return the trail surrogate from the previous invocation. */
61 if (cs->trail_surrogate >= 0xdc00 && cs->trail_surrogate <= 0xdfff) {
62 *pc16 = cs->trail_surrogate;
63 cs->trail_surrogate = 0;
64 return ((size_t)-3);
65 }
66
67 len = mbrtoc32_l(&c32, s, n, &cs->c32_mbstate, locale);
68 if (len >= 0) {
69 if (c32 < 0x10000) {
70 /* Fits in one UTF-16 character. */
71 *pc16 = c32;
72 } else {
73 /* Split up in a surrogate pair. */
74 c32 -= 0x10000;
75 *pc16 = 0xd800 | (c32 >> 10);
76 cs->trail_surrogate = 0xdc00 | (c32 & 0x3ff);
77 }
78 }
79 return (len);
80 }
81
82 size_t
mbrtoc16(char16_t * __restrict pc16,const char * __restrict s,size_t n,mbstate_t * __restrict ps)83 mbrtoc16(char16_t * __restrict pc16, const char * __restrict s, size_t n,
84 mbstate_t * __restrict ps)
85 {
86
87 return (mbrtoc16_l(pc16, s, n, ps, __get_locale()));
88 }
89