Update.
[glibc.git] / wcsmbs / mbsnrtowcs.c
blob9ac06fe6c22182a0abf45b124f835573823db908
1 /* Copyright (C) 1996,1997,1998,1999,2000,2002 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Ulrich Drepper <drepper@gnu.org>, 1996.
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.
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.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, write to the Free
17 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
18 02111-1307 USA. */
20 #include <dlfcn.h>
21 #include <errno.h>
22 #include <gconv.h>
23 #include <string.h>
24 #include <wchar.h>
25 #include <wcsmbsload.h>
27 #include <assert.h>
29 #ifndef EILSEQ
30 # define EILSEQ EINVAL
31 #endif
34 /* This is the private state used if PS is NULL. */
35 static mbstate_t state;
37 /* This is a non-standard function but it is very useful in the
38 implementation of stdio because we have to deal with unterminated
39 buffers. At most NMC bytes will be converted. */
40 size_t
41 __mbsnrtowcs (dst, src, nmc, len, ps)
42 wchar_t *dst;
43 const char **src;
44 size_t nmc;
45 size_t len;
46 mbstate_t *ps;
48 const unsigned char *srcend;
49 struct __gconv_step_data data;
50 size_t result;
51 int status;
52 struct __gconv_step *towc;
53 size_t dummy;
54 const struct gconv_fcts *fcts;
56 /* Tell where we want the result. */
57 data.__invocation_counter = 0;
58 data.__internal_use = 1;
59 data.__flags = __GCONV_IS_LAST;
60 data.__statep = ps ?: &state;
61 data.__trans = NULL;
63 if (nmc == 0)
64 return 0;
65 srcend = *src + __strnlen (*src, nmc - 1) + 1;
67 /* Get the conversion functions. */
68 fcts = get_gconv_fcts (_NL_CURRENT_DATA (LC_CTYPE));
70 /* Get the structure with the function pointers. */
71 towc = fcts->towc;
73 /* We have to handle DST == NULL special. */
74 if (dst == NULL)
76 wchar_t buf[64]; /* Just an arbitrary size. */
77 const unsigned char *inbuf = *src;
79 result = 0;
80 data.__outbufend = (unsigned char *) buf + sizeof (buf);
83 data.__outbuf = (unsigned char *) buf;
85 status = DL_CALL_FCT (towc->__fct,
86 (towc, &data, &inbuf, srcend, NULL,
87 &dummy, 0, 1));
89 result += (wchar_t *) data.__outbuf - buf;
91 while (status == __GCONV_FULL_OUTPUT);
93 if ((status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
94 && ((wchar_t *) data.__outbuf)[-1] == L'\0')
95 /* Don't count the NUL character in. */
96 --result;
98 else
100 /* This code is based on the safe assumption that all internal
101 multi-byte encodings use the NUL byte only to mark the end
102 of the string. */
103 data.__outbuf = (unsigned char *) dst;
104 data.__outbufend = data.__outbuf + len * sizeof (wchar_t);
106 status = DL_CALL_FCT (towc->__fct,
107 (towc, &data, (const unsigned char **) src, srcend,
108 NULL, &dummy, 0, 1));
110 result = (wchar_t *) data.__outbuf - dst;
112 /* We have to determine whether the last character converted
113 is the NUL character. */
114 if ((status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
115 && (assert (result > 0),
116 ((wchar_t *) dst)[result - 1] == L'\0'))
118 assert (__mbsinit (data.__statep));
119 *src = NULL;
120 --result;
124 /* There must not be any problems with the conversion but illegal input
125 characters. */
126 assert (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT
127 || status == __GCONV_ILLEGAL_INPUT
128 || status == __GCONV_INCOMPLETE_INPUT
129 || status == __GCONV_FULL_OUTPUT);
131 if (status != __GCONV_OK && status != __GCONV_FULL_OUTPUT
132 && status != __GCONV_EMPTY_INPUT && status != __GCONV_INCOMPLETE_INPUT)
134 result = (size_t) -1;
135 __set_errno (EILSEQ);
138 return result;
140 weak_alias (__mbsnrtowcs, mbsnrtowcs)