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 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 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