.
[glibc/history.git] / wcsmbs / mbrtowc.c
blobb53457173611a619a9327cb99162dd2a01fe66bc
1 /* Copyright (C) 1996, 1997, 1998, 1999, 2000, 2002, 2004, 2005
2 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Ulrich Drepper <drepper@gnu.org>, 1996.
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, write to the Free
18 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
19 02111-1307 USA. */
21 #include <assert.h>
22 #include <dlfcn.h>
23 #include <errno.h>
24 #include <gconv.h>
25 #include <wchar.h>
26 #include <wcsmbsload.h>
28 #include <sysdep.h>
30 #ifndef EILSEQ
31 # define EILSEQ EINVAL
32 #endif
34 /* This is the private state used if PS is NULL. */
35 static mbstate_t state;
37 size_t
38 __mbrtowc (wchar_t *pwc, const char *s, size_t n, mbstate_t *ps)
40 wchar_t buf[1];
41 struct __gconv_step_data data;
42 int status;
43 size_t result;
44 size_t dummy;
45 const unsigned char *inbuf, *endbuf;
46 unsigned char *outbuf = (unsigned char *) (pwc ?: buf);
47 const struct gconv_fcts *fcts;
49 /* Set information for this step. */
50 data.__invocation_counter = 0;
51 data.__internal_use = 1;
52 data.__flags = __GCONV_IS_LAST;
53 data.__statep = ps ?: &state;
54 data.__trans = NULL;
56 /* A first special case is if S is NULL. This means put PS in the
57 initial state. */
58 if (s == NULL)
60 outbuf = (unsigned char *) buf;
61 s = "";
62 n = 1;
65 /* Tell where we want the result. */
66 data.__outbuf = outbuf;
67 data.__outbufend = outbuf + sizeof (wchar_t);
69 /* Get the conversion functions. */
70 fcts = get_gconv_fcts (_NL_CURRENT_DATA (LC_CTYPE));
72 /* Do a normal conversion. */
73 inbuf = (const unsigned char *) s;
74 endbuf = inbuf + n;
75 if (__builtin_expect (endbuf < inbuf, 0))
76 endbuf = (const unsigned char *) ~(uintptr_t) 0;
77 __gconv_fct fct = fcts->towc->__fct;
78 #ifdef PTR_DEMANGLE
79 if (fcts->towc->__shlib_handle != NULL)
80 PTR_DEMANGLE (fct);
81 #endif
82 status = DL_CALL_FCT (fct, (fcts->towc, &data, &inbuf, endbuf,
83 NULL, &dummy, 0, 1));
85 /* There must not be any problems with the conversion but illegal input
86 characters. The output buffer must be large enough, otherwise the
87 definition of MB_CUR_MAX is not correct. All the other possible
88 errors also must not happen. */
89 assert (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT
90 || status == __GCONV_ILLEGAL_INPUT
91 || status == __GCONV_INCOMPLETE_INPUT
92 || status == __GCONV_FULL_OUTPUT);
94 if (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT
95 || status == __GCONV_FULL_OUTPUT)
97 if (data.__outbuf != (unsigned char *) outbuf
98 && *(wchar_t *) outbuf == L'\0')
100 /* The converted character is the NUL character. */
101 assert (__mbsinit (data.__statep));
102 result = 0;
104 else
105 result = inbuf - (const unsigned char *) s;
107 else if (status == __GCONV_INCOMPLETE_INPUT)
108 result = (size_t) -2;
109 else
111 result = (size_t) -1;
112 __set_errno (EILSEQ);
115 return result;
117 libc_hidden_def (__mbrtowc)
118 weak_alias (__mbrtowc, mbrtowc)
119 libc_hidden_weak (mbrtowc)