1/* Copyright (C) 1996-2022 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <https://www.gnu.org/licenses/>. */
17
18#include <assert.h>
19#include <dlfcn.h>
20#include <errno.h>
21#include <gconv.h>
22#include <wchar.h>
23#include <wcsmbsload.h>
24
25#include <sysdep.h>
26
27#ifndef EILSEQ
28# define EILSEQ EINVAL
29#endif
30
31
32/* This is the private state used if PS is NULL. */
33static mbstate_t state;
34
35/* This is a non-standard function but it is very useful in the
36 implementation of stdio because we have to deal with unterminated
37 buffers. At most NWC wide character will be converted. */
38size_t
39__wcsnrtombs (char *dst, const wchar_t **src, size_t nwc, size_t len,
40 mbstate_t *ps)
41{
42 struct __gconv_step_data data;
43 const wchar_t *srcend;
44 int status;
45 size_t result;
46 struct __gconv_step *tomb;
47 const struct gconv_fcts *fcts;
48
49 /* Tell where we want the result. */
50 data.__invocation_counter = 0;
51 data.__internal_use = 1;
52 data.__flags = __GCONV_IS_LAST;
53 data.__statep = ps ?: &state;
54
55 if (nwc == 0)
56 return 0;
57 srcend = *src + __wcsnlen (*src, nwc - 1) + 1;
58
59 /* Get the conversion functions. */
60 fcts = get_gconv_fcts (_NL_CURRENT_DATA (LC_CTYPE));
61
62 /* Get the structure with the function pointers. */
63 tomb = fcts->tomb;
64 __gconv_fct fct = tomb->__fct;
65#ifdef PTR_DEMANGLE
66 if (tomb->__shlib_handle != NULL)
67 PTR_DEMANGLE (fct);
68#endif
69
70 /* We have to handle DST == NULL special. */
71 if (dst == NULL)
72 {
73 mbstate_t temp_state;
74 unsigned char buf[256]; /* Just an arbitrary value. */
75 const unsigned char *inbuf = (const unsigned char *) *src;
76 size_t dummy;
77
78 temp_state = *data.__statep;
79 data.__statep = &temp_state;
80
81 result = 0;
82 data.__outbufend = buf + sizeof (buf);
83
84 do
85 {
86 data.__outbuf = buf;
87
88 status = DL_CALL_FCT (fct, (tomb, &data, &inbuf,
89 (const unsigned char *) srcend, NULL,
90 &dummy, 0, 1));
91
92 /* Count the number of bytes. */
93 result += data.__outbuf - buf;
94 }
95 while (status == __GCONV_FULL_OUTPUT);
96
97 if ((status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
98 && data.__outbuf[-1] == '\0')
99 /* Don't count the NUL character in. */
100 --result;
101 }
102 else
103 {
104 /* This code is based on the safe assumption that all internal
105 multi-byte encodings use the NUL byte only to mark the end
106 of the string. */
107 size_t dummy;
108
109 data.__outbuf = (unsigned char *) dst;
110 data.__outbufend = (unsigned char *) dst + len;
111
112 status = DL_CALL_FCT (fct, (tomb, &data, (const unsigned char **) src,
113 (const unsigned char *) srcend, NULL,
114 &dummy, 0, 1));
115
116 /* Count the number of bytes. */
117 result = data.__outbuf - (unsigned char *) dst;
118
119 /* We have to determine whether the last character converted
120 is the NUL character. */
121 if ((status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
122 && data.__outbuf[-1] == '\0')
123 {
124 assert (data.__outbuf != (unsigned char *) dst);
125 assert (__mbsinit (data.__statep));
126 *src = NULL;
127 --result;
128 }
129 }
130
131 /* There must not be any problems with the conversion but illegal input
132 characters. */
133 assert (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT
134 || status == __GCONV_ILLEGAL_INPUT
135 || status == __GCONV_INCOMPLETE_INPUT
136 || status == __GCONV_FULL_OUTPUT);
137
138 if (status != __GCONV_OK && status != __GCONV_FULL_OUTPUT
139 && status != __GCONV_EMPTY_INPUT)
140 {
141 result = (size_t) -1;
142 __set_errno (EILSEQ);
143 }
144
145 return result;
146}
147weak_alias (__wcsnrtombs, wcsnrtombs)
148