1/* Copyright (C) 1996-2021 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Ulrich Drepper <drepper@gnu.org>, 1996.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19#include <assert.h>
20#include <dlfcn.h>
21#include <errno.h>
22#include <gconv.h>
23#include <wchar.h>
24#include <wcsmbsload.h>
25
26#include <sysdep.h>
27
28#ifndef EILSEQ
29# define EILSEQ EINVAL
30#endif
31
32
33/* This is the private state used if PS is NULL. */
34static mbstate_t state;
35
36/* This is a non-standard function but it is very useful in the
37 implementation of stdio because we have to deal with unterminated
38 buffers. At most NWC wide character will be converted. */
39size_t
40__wcsnrtombs (char *dst, const wchar_t **src, size_t nwc, size_t len,
41 mbstate_t *ps)
42{
43 struct __gconv_step_data data;
44 const wchar_t *srcend;
45 int status;
46 size_t result;
47 struct __gconv_step *tomb;
48 const struct gconv_fcts *fcts;
49
50 /* Tell where we want the result. */
51 data.__invocation_counter = 0;
52 data.__internal_use = 1;
53 data.__flags = __GCONV_IS_LAST;
54 data.__statep = ps ?: &state;
55
56 if (nwc == 0)
57 return 0;
58 srcend = *src + __wcsnlen (*src, nwc - 1) + 1;
59
60 /* Get the conversion functions. */
61 fcts = get_gconv_fcts (_NL_CURRENT_DATA (LC_CTYPE));
62
63 /* Get the structure with the function pointers. */
64 tomb = fcts->tomb;
65 __gconv_fct fct = tomb->__fct;
66#ifdef PTR_DEMANGLE
67 if (tomb->__shlib_handle != NULL)
68 PTR_DEMANGLE (fct);
69#endif
70
71 /* We have to handle DST == NULL special. */
72 if (dst == NULL)
73 {
74 mbstate_t temp_state;
75 unsigned char buf[256]; /* Just an arbitrary value. */
76 const unsigned char *inbuf = (const unsigned char *) *src;
77 size_t dummy;
78
79 temp_state = *data.__statep;
80 data.__statep = &temp_state;
81
82 result = 0;
83 data.__outbufend = buf + sizeof (buf);
84
85 do
86 {
87 data.__outbuf = buf;
88
89 status = DL_CALL_FCT (fct, (tomb, &data, &inbuf,
90 (const unsigned char *) srcend, NULL,
91 &dummy, 0, 1));
92
93 /* Count the number of bytes. */
94 result += data.__outbuf - buf;
95 }
96 while (status == __GCONV_FULL_OUTPUT);
97
98 if ((status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
99 && data.__outbuf[-1] == '\0')
100 /* Don't count the NUL character in. */
101 --result;
102 }
103 else
104 {
105 /* This code is based on the safe assumption that all internal
106 multi-byte encodings use the NUL byte only to mark the end
107 of the string. */
108 size_t dummy;
109
110 data.__outbuf = (unsigned char *) dst;
111 data.__outbufend = (unsigned char *) dst + len;
112
113 status = DL_CALL_FCT (fct, (tomb, &data, (const unsigned char **) src,
114 (const unsigned char *) srcend, NULL,
115 &dummy, 0, 1));
116
117 /* Count the number of bytes. */
118 result = data.__outbuf - (unsigned char *) dst;
119
120 /* We have to determine whether the last character converted
121 is the NUL character. */
122 if ((status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
123 && data.__outbuf[-1] == '\0')
124 {
125 assert (data.__outbuf != (unsigned char *) dst);
126 assert (__mbsinit (data.__statep));
127 *src = NULL;
128 --result;
129 }
130 }
131
132 /* There must not be any problems with the conversion but illegal input
133 characters. */
134 assert (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT
135 || status == __GCONV_ILLEGAL_INPUT
136 || status == __GCONV_INCOMPLETE_INPUT
137 || status == __GCONV_FULL_OUTPUT);
138
139 if (status != __GCONV_OK && status != __GCONV_FULL_OUTPUT
140 && status != __GCONV_EMPTY_INPUT)
141 {
142 result = (size_t) -1;
143 __set_errno (EILSEQ);
144 }
145
146 return result;
147}
148weak_alias (__wcsnrtombs, wcsnrtombs)
149