xref: /freebsd/lib/libc/locale/mbrtocXX_iconv.h (revision 0b3105a37d7adcadcb720112fed4dc4e8040be99)
1 /*-
2  * Copyright (c) 2013 Ed Schouten <ed@FreeBSD.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
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 "xlocale_private.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 = &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 		handle->cv_shared->ci_discard_ilseq = true;
82 		handle->cv_shared->ci_hooks = NULL;
83 		cs->srcbuf_len = cs->dstbuf_len = 0;
84 		cs->initialized = true;
85 		if (s == NULL)
86 			return (0);
87 	}
88 
89 	/* See if we still have characters left from the previous invocation. */
90 	if (cs->dstbuf_len > 0) {
91 		retval = (size_t)-3;
92 		goto return_char;
93 	}
94 
95 	/* Fill up the read buffer as far as possible. */
96 	if (n > sizeof(cs->srcbuf) - cs->srcbuf_len)
97 		n = sizeof(cs->srcbuf) - cs->srcbuf_len;
98 	memcpy(cs->srcbuf + cs->srcbuf_len, s, n);
99 
100 	/* Convert as few characters to the dst buffer as possible. */
101 	for (i = 0; ; i++) {
102 		char *src, *dst;
103 		size_t srcleft, dstleft, invlen;
104 		int err;
105 
106 		src = cs->srcbuf;
107 		srcleft = cs->srcbuf_len + n;
108 		dst = cs->dstbuf.bytes;
109 		dstleft = i * sizeof(charXX_t);
110 		assert(srcleft <= sizeof(cs->srcbuf) &&
111 		    dstleft <= sizeof(cs->dstbuf.bytes));
112 		err = _citrus_iconv_convert(handle, &src, &srcleft,
113 		    &dst, &dstleft, 0, &invlen);
114 		cs->dstbuf_len = (dst - cs->dstbuf.bytes) / sizeof(charXX_t);
115 
116 		/* Got new character(s). Return the first. */
117 		if (cs->dstbuf_len > 0) {
118 			assert(src - cs->srcbuf > cs->srcbuf_len);
119 			retval = src - cs->srcbuf - cs->srcbuf_len;
120 			cs->srcbuf_len = 0;
121 			goto return_char;
122 		}
123 
124 		/* Increase dst buffer size, to obtain the surrogate pair. */
125 		if (err == E2BIG)
126 			continue;
127 
128 		/* Illegal sequence. */
129 		if (invlen > 0) {
130 			cs->srcbuf_len = 0;
131 			errno = EILSEQ;
132 			return ((size_t)-1);
133 		}
134 
135 		/* Save unprocessed remainder for the next invocation. */
136 		memmove(cs->srcbuf, src, srcleft);
137 		cs->srcbuf_len = srcleft;
138 		return ((size_t)-2);
139 	}
140 
141 return_char:
142 	retchar = cs->dstbuf.widechar[0];
143 	memmove(&cs->dstbuf.widechar[0], &cs->dstbuf.widechar[1],
144 	    --cs->dstbuf_len * sizeof(charXX_t));
145 	if (pc != NULL)
146 		*pc = retchar;
147 	if (retchar == 0)
148 		return (0);
149 	return (retval);
150 }
151 
152 size_t
153 mbrtocXX(charXX_t * __restrict pc, const char * __restrict s, size_t n,
154     mbstate_t * __restrict ps)
155 {
156 
157 	return (mbrtocXX_l(pc, s, n, ps, __get_locale()));
158 }
159