xref: /freebsd/lib/libc/locale/mbrtocXX_iconv.h (revision 1c1f229e9156dd75cab5e0e3e586c5ef319d68ee)
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 <sys/cdefs.h>
30 #include <sys/queue.h>
31 
32 #include <assert.h>
33 #include <errno.h>
34 #include <langinfo.h>
35 #include <limits.h>
36 #include <string.h>
37 #include <uchar.h>
38 
39 #include "../iconv/citrus_hash.h"
40 #include "../iconv/citrus_module.h"
41 #include "../iconv/citrus_iconv.h"
42 #include "mblocal.h"
43 
44 typedef struct {
45 	bool			initialized;
46 	struct _citrus_iconv	iconv;
47 	char			srcbuf[MB_LEN_MAX];
48 	size_t			srcbuf_len;
49 	union {
50 		charXX_t	widechar[DSTBUF_LEN];
51 		char		bytes[sizeof(charXX_t) * DSTBUF_LEN];
52 	} dstbuf;
53 	size_t			dstbuf_len;
54 } _ConversionState;
55 _Static_assert(sizeof(_ConversionState) <= sizeof(mbstate_t),
56     "Size of _ConversionState must not exceed mbstate_t's size.");
57 
58 size_t
59 mbrtocXX_l(charXX_t * __restrict pc, const char * __restrict s, size_t n,
60     mbstate_t * __restrict ps, locale_t locale)
61 {
62 	_ConversionState *cs;
63 	struct _citrus_iconv *handle;
64 	size_t i, retval;
65 	charXX_t retchar;
66 
67 	FIX_LOCALE(locale);
68 	if (ps == NULL)
69 		ps = &(XLOCALE_CTYPE(locale)->mbrtocXX);
70 	cs = (_ConversionState *)ps;
71 	handle = &cs->iconv;
72 
73 	/* Reinitialize mbstate_t. */
74 	if (s == NULL || !cs->initialized) {
75 		if (_citrus_iconv_open(&handle,
76 		    nl_langinfo_l(CODESET, locale), UTF_XX_INTERNAL) != 0) {
77 			cs->initialized = false;
78 			errno = EINVAL;
79 			return (-1);
80 		}
81 		cs->srcbuf_len = cs->dstbuf_len = 0;
82 		cs->initialized = true;
83 		if (s == NULL)
84 			return (0);
85 	}
86 
87 	/* See if we still have characters left from the previous invocation. */
88 	if (cs->dstbuf_len > 0) {
89 		retval = (size_t)-3;
90 		goto return_char;
91 	}
92 
93 	/* Fill up the read buffer as far as possible. */
94 	if (n > sizeof(cs->srcbuf) - cs->srcbuf_len)
95 		n = sizeof(cs->srcbuf) - cs->srcbuf_len;
96 	memcpy(cs->srcbuf + cs->srcbuf_len, s, n);
97 
98 	/* Convert as few characters to the dst buffer as possible. */
99 	for (i = 0; ; i++) {
100 		char *src, *dst;
101 		size_t srcleft, dstleft, invlen;
102 		int err;
103 
104 		src = cs->srcbuf;
105 		srcleft = cs->srcbuf_len + n;
106 		dst = cs->dstbuf.bytes;
107 		dstleft = i * sizeof(charXX_t);
108 		assert(srcleft <= sizeof(cs->srcbuf) &&
109 		    dstleft <= sizeof(cs->dstbuf.bytes));
110 		err = _citrus_iconv_convert(handle, &src, &srcleft,
111 		    &dst, &dstleft, _CITRUS_ICONV_F_HIDE_INVALID, &invlen);
112 		cs->dstbuf_len = (dst - cs->dstbuf.bytes) / sizeof(charXX_t);
113 
114 		/* Got new character(s). Return the first. */
115 		if (cs->dstbuf_len > 0) {
116 			assert(src - cs->srcbuf > cs->srcbuf_len);
117 			retval = src - cs->srcbuf - cs->srcbuf_len;
118 			cs->srcbuf_len = 0;
119 			goto return_char;
120 		}
121 
122 		/* Increase dst buffer size, to obtain the surrogate pair. */
123 		if (err == E2BIG)
124 			continue;
125 
126 		/* Illegal sequence. */
127 		if (invlen > 0) {
128 			cs->srcbuf_len = 0;
129 			errno = EILSEQ;
130 			return ((size_t)-1);
131 		}
132 
133 		/* Save unprocessed remainder for the next invocation. */
134 		memmove(cs->srcbuf, src, srcleft);
135 		cs->srcbuf_len = srcleft;
136 		return ((size_t)-2);
137 	}
138 
139 return_char:
140 	retchar = cs->dstbuf.widechar[0];
141 	memmove(&cs->dstbuf.widechar[0], &cs->dstbuf.widechar[1],
142 	    --cs->dstbuf_len * sizeof(charXX_t));
143 	if (pc != NULL)
144 		*pc = retchar;
145 	if (retchar == 0)
146 		return (0);
147 	return (retval);
148 }
149 
150 size_t
151 mbrtocXX(charXX_t * __restrict pc, const char * __restrict s, size_t n,
152     mbstate_t * __restrict ps)
153 {
154 
155 	return (mbrtocXX_l(pc, s, n, ps, __get_locale()));
156 }
157