xref: /freebsd/lib/libc/locale/mbrtocXX_iconv.h (revision 0957b409a90fd597c1e9124cbaf3edd2b488f4ac)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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 __FBSDID("$FreeBSD$");
31 
32 #include <sys/queue.h>
33 
34 #include <assert.h>
35 #include <errno.h>
36 #include <langinfo.h>
37 #include <limits.h>
38 #include <string.h>
39 #include <uchar.h>
40 
41 #include "../iconv/citrus_hash.h"
42 #include "../iconv/citrus_module.h"
43 #include "../iconv/citrus_iconv.h"
44 #include "mblocal.h"
45 
46 typedef struct {
47 	bool			initialized;
48 	struct _citrus_iconv	iconv;
49 	char			srcbuf[MB_LEN_MAX];
50 	size_t			srcbuf_len;
51 	union {
52 		charXX_t	widechar[DSTBUF_LEN];
53 		char		bytes[sizeof(charXX_t) * DSTBUF_LEN];
54 	} dstbuf;
55 	size_t			dstbuf_len;
56 } _ConversionState;
57 _Static_assert(sizeof(_ConversionState) <= sizeof(mbstate_t),
58     "Size of _ConversionState must not exceed mbstate_t's size.");
59 
60 size_t
61 mbrtocXX_l(charXX_t * __restrict pc, const char * __restrict s, size_t n,
62     mbstate_t * __restrict ps, locale_t locale)
63 {
64 	_ConversionState *cs;
65 	struct _citrus_iconv *handle;
66 	size_t i, retval;
67 	charXX_t retchar;
68 
69 	FIX_LOCALE(locale);
70 	if (ps == NULL)
71 		ps = &(XLOCALE_CTYPE(locale)->mbrtocXX);
72 	cs = (_ConversionState *)ps;
73 	handle = &cs->iconv;
74 
75 	/* Reinitialize mbstate_t. */
76 	if (s == NULL || !cs->initialized) {
77 		if (_citrus_iconv_open(&handle,
78 		    nl_langinfo_l(CODESET, locale), UTF_XX_INTERNAL) != 0) {
79 			cs->initialized = false;
80 			errno = EINVAL;
81 			return (-1);
82 		}
83 		handle->cv_shared->ci_discard_ilseq = true;
84 		handle->cv_shared->ci_hooks = NULL;
85 		cs->srcbuf_len = cs->dstbuf_len = 0;
86 		cs->initialized = true;
87 		if (s == NULL)
88 			return (0);
89 	}
90 
91 	/* See if we still have characters left from the previous invocation. */
92 	if (cs->dstbuf_len > 0) {
93 		retval = (size_t)-3;
94 		goto return_char;
95 	}
96 
97 	/* Fill up the read buffer as far as possible. */
98 	if (n > sizeof(cs->srcbuf) - cs->srcbuf_len)
99 		n = sizeof(cs->srcbuf) - cs->srcbuf_len;
100 	memcpy(cs->srcbuf + cs->srcbuf_len, s, n);
101 
102 	/* Convert as few characters to the dst buffer as possible. */
103 	for (i = 0; ; i++) {
104 		char *src, *dst;
105 		size_t srcleft, dstleft, invlen;
106 		int err;
107 
108 		src = cs->srcbuf;
109 		srcleft = cs->srcbuf_len + n;
110 		dst = cs->dstbuf.bytes;
111 		dstleft = i * sizeof(charXX_t);
112 		assert(srcleft <= sizeof(cs->srcbuf) &&
113 		    dstleft <= sizeof(cs->dstbuf.bytes));
114 		err = _citrus_iconv_convert(handle, &src, &srcleft,
115 		    &dst, &dstleft, 0, &invlen);
116 		cs->dstbuf_len = (dst - cs->dstbuf.bytes) / sizeof(charXX_t);
117 
118 		/* Got new character(s). Return the first. */
119 		if (cs->dstbuf_len > 0) {
120 			assert(src - cs->srcbuf > cs->srcbuf_len);
121 			retval = src - cs->srcbuf - cs->srcbuf_len;
122 			cs->srcbuf_len = 0;
123 			goto return_char;
124 		}
125 
126 		/* Increase dst buffer size, to obtain the surrogate pair. */
127 		if (err == E2BIG)
128 			continue;
129 
130 		/* Illegal sequence. */
131 		if (invlen > 0) {
132 			cs->srcbuf_len = 0;
133 			errno = EILSEQ;
134 			return ((size_t)-1);
135 		}
136 
137 		/* Save unprocessed remainder for the next invocation. */
138 		memmove(cs->srcbuf, src, srcleft);
139 		cs->srcbuf_len = srcleft;
140 		return ((size_t)-2);
141 	}
142 
143 return_char:
144 	retchar = cs->dstbuf.widechar[0];
145 	memmove(&cs->dstbuf.widechar[0], &cs->dstbuf.widechar[1],
146 	    --cs->dstbuf_len * sizeof(charXX_t));
147 	if (pc != NULL)
148 		*pc = retchar;
149 	if (retchar == 0)
150 		return (0);
151 	return (retval);
152 }
153 
154 size_t
155 mbrtocXX(charXX_t * __restrict pc, const char * __restrict s, size_t n,
156     mbstate_t * __restrict ps)
157 {
158 
159 	return (mbrtocXX_l(pc, s, n, ps, __get_locale()));
160 }
161