1 /* Convert multibyte character to wide character.
2    Copyright (C) 1999-2002, 2005-2021 Free Software Foundation, Inc.
3    Written by Bruno Haible <bruno@clisp.org>, 2008.
4 
5    This program is free software: you can redistribute it and/or modify
6    it under the terms of the GNU General Public License as published by
7    the Free Software Foundation; either version 3 of the License, or
8    (at your option) any later version.
9 
10    This program 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
13    GNU General Public License for more details.
14 
15    You should have received a copy of the GNU General Public License
16    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
17 
18 #include <config.h>
19 
20 /* Specification.  */
21 #include <wchar.h>
22 
23 #if GNULIB_defined_mbstate_t
24 /* Implement mbrtowc() on top of mbtowc() for the non-UTF-8 locales
25    and directly for the UTF-8 locales.  */
26 
27 # include <errno.h>
28 # include <stdint.h>
29 # include <stdlib.h>
30 
31 # if defined _WIN32 && !defined __CYGWIN__
32 
33 #  define WIN32_LEAN_AND_MEAN  /* avoid including junk */
34 #  include <windows.h>
35 
36 # elif HAVE_PTHREAD_API
37 
38 #  include <pthread.h>
39 #  if HAVE_THREADS_H && HAVE_WEAK_SYMBOLS
40 #   include <threads.h>
41 #   pragma weak thrd_exit
42 #   define c11_threads_in_use() (thrd_exit != NULL)
43 #  else
44 #   define c11_threads_in_use() 0
45 #  endif
46 
47 # elif HAVE_THREADS_H
48 
49 #  include <threads.h>
50 
51 # endif
52 
53 # include "attribute.h"
54 # include "verify.h"
55 # include "lc-charset-dispatch.h"
56 # include "mbtowc-lock.h"
57 
58 verify (sizeof (mbstate_t) >= 4);
59 static char internal_state[4];
60 
61 size_t
mbrtowc(wchar_t * pwc,const char * s,size_t n,mbstate_t * ps)62 mbrtowc (wchar_t *pwc, const char *s, size_t n, mbstate_t *ps)
63 {
64 # define FITS_IN_CHAR_TYPE(wc)  ((wc) <= WCHAR_MAX)
65 # include "mbrtowc-impl.h"
66 }
67 
68 #else
69 /* Override the system's mbrtowc() function.  */
70 
71 # if MBRTOWC_IN_C_LOCALE_MAYBE_EILSEQ
72 #  include "hard-locale.h"
73 #  include <locale.h>
74 # endif
75 
76 # undef mbrtowc
77 
78 size_t
rpl_mbrtowc(wchar_t * pwc,const char * s,size_t n,mbstate_t * ps)79 rpl_mbrtowc (wchar_t *pwc, const char *s, size_t n, mbstate_t *ps)
80 {
81   size_t ret;
82   wchar_t wc;
83 
84 # if MBRTOWC_NULL_ARG2_BUG || MBRTOWC_RETVAL_BUG || MBRTOWC_EMPTY_INPUT_BUG
85   if (s == NULL)
86     {
87       pwc = NULL;
88       s = "";
89       n = 1;
90     }
91 # endif
92 
93 # if MBRTOWC_EMPTY_INPUT_BUG
94   if (n == 0)
95     return (size_t) -2;
96 # endif
97 
98   if (! pwc)
99     pwc = &wc;
100 
101 # if MBRTOWC_RETVAL_BUG
102   {
103     static mbstate_t internal_state;
104 
105     /* Override mbrtowc's internal state.  We cannot call mbsinit() on the
106        hidden internal state, but we can call it on our variable.  */
107     if (ps == NULL)
108       ps = &internal_state;
109 
110     if (!mbsinit (ps))
111       {
112         /* Parse the rest of the multibyte character byte for byte.  */
113         size_t count = 0;
114         for (; n > 0; s++, n--)
115           {
116             ret = mbrtowc (&wc, s, 1, ps);
117 
118             if (ret == (size_t)(-1))
119               return (size_t)(-1);
120             count++;
121             if (ret != (size_t)(-2))
122               {
123                 /* The multibyte character has been completed.  */
124                 *pwc = wc;
125                 return (wc == 0 ? 0 : count);
126               }
127           }
128         return (size_t)(-2);
129       }
130   }
131 # endif
132 
133 # if MBRTOWC_STORES_INCOMPLETE_BUG
134   ret = mbrtowc (&wc, s, n, ps);
135   if (ret < (size_t) -2 && pwc != NULL)
136     *pwc = wc;
137 # else
138   ret = mbrtowc (pwc, s, n, ps);
139 # endif
140 
141 # if MBRTOWC_NUL_RETVAL_BUG
142   if (ret < (size_t) -2 && !*pwc)
143     return 0;
144 # endif
145 
146 # if MBRTOWC_IN_C_LOCALE_MAYBE_EILSEQ
147   if ((size_t) -2 <= ret && n != 0 && ! hard_locale (LC_CTYPE))
148     {
149       unsigned char uc = *s;
150       *pwc = uc;
151       return 1;
152     }
153 # endif
154 
155   return ret;
156 }
157 
158 #endif
159