1 /* Copyright (C) 1996-2022 Free Software Foundation, Inc.
2    Copyright The GNU Toolchain Authors.
3    This file is part of the GNU C Library.
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 <stdlib.h>
24 #include <string.h>
25 #include <wchar.h>
26 #include <wcsmbsload.h>
27 
28 #include <sysdep.h>
29 
30 #ifndef EILSEQ
31 # define EILSEQ EINVAL
32 #endif
33 
34 
35 /* This is the private state used if PS is NULL.  */
36 static mbstate_t state;
37 
38 size_t
__wcrtomb_internal(char * s,wchar_t wc,mbstate_t * ps,size_t s_size)39 __wcrtomb_internal (char *s, wchar_t wc, mbstate_t *ps, size_t s_size)
40 {
41   char buf[MB_LEN_MAX];
42   struct __gconv_step_data data;
43   int status;
44   size_t result;
45   size_t dummy;
46   const struct gconv_fcts *fcts;
47 
48   /* Set information for this step.  */
49   data.__invocation_counter = 0;
50   data.__internal_use = 1;
51   data.__flags = __GCONV_IS_LAST;
52   data.__statep = ps ?: &state;
53 
54   /* A first special case is if S is NULL.  This means put PS in the
55      initial state.  */
56   if (s == NULL)
57     wc = L'\0';
58 
59   /* Tell where we want to have the result.  */
60   data.__outbuf = (unsigned char *) buf;
61   data.__outbufend = (unsigned char *) buf + sizeof buf;
62 
63   /* Get the conversion functions.  */
64   fcts = get_gconv_fcts (_NL_CURRENT_DATA (LC_CTYPE));
65   __gconv_fct fct = fcts->tomb->__fct;
66 #ifdef PTR_DEMANGLE
67   if (fcts->tomb->__shlib_handle != NULL)
68     PTR_DEMANGLE (fct);
69 #endif
70 
71   /* If WC is the NUL character we write into the output buffer the byte
72      sequence necessary for PS to get into the initial state, followed
73      by a NUL byte.  */
74   if (wc == L'\0')
75     {
76       status = DL_CALL_FCT (fct, (fcts->tomb, &data, NULL, NULL,
77 				  NULL, &dummy, 1, 1));
78 
79       if (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
80 	*data.__outbuf++ = '\0';
81     }
82   else
83     {
84       /* Do a normal conversion.  */
85       const unsigned char *inbuf = (const unsigned char *) &wc;
86 
87       status = DL_CALL_FCT (fct,
88 			    (fcts->tomb, &data, &inbuf,
89 			     inbuf + sizeof (wchar_t), NULL, &dummy, 0, 1));
90     }
91 
92   /* There must not be any problems with the conversion but illegal input
93      characters.  The output buffer must be large enough, otherwise the
94      definition of MB_CUR_MAX is not correct.  All the other possible
95      errors also must not happen.  */
96   assert (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT
97 	  || status == __GCONV_ILLEGAL_INPUT
98 	  || status == __GCONV_INCOMPLETE_INPUT
99 	  || status == __GCONV_FULL_OUTPUT);
100 
101   if (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT
102       || status == __GCONV_FULL_OUTPUT)
103     {
104       result = data.__outbuf - (unsigned char *) buf;
105 
106       if (s != NULL)
107 	{
108 	  if (result > s_size)
109 	    __chk_fail ();
110 
111 	  memcpy (s, buf, result);
112 	}
113     }
114   else
115     {
116       result = (size_t) -1;
117       __set_errno (EILSEQ);
118     }
119 
120   return result;
121 }
122 
123 size_t
__wcrtomb(char * s,wchar_t wc,mbstate_t * ps)124 __wcrtomb (char *s, wchar_t wc, mbstate_t *ps)
125 {
126   return __wcrtomb_internal (s, wc, ps, (size_t) -1);
127 }
128 weak_alias (__wcrtomb, wcrtomb)
129 libc_hidden_weak (wcrtomb)
130