1 /* Copyright (C) 2002-2022 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 <ctype.h>
20 #include <string.h>
21 #include "wcsmbsload.h"
22 #include <dlfcn.h>
23 #include <errno.h>
24 #include <gconv.h>
25 #include <stdlib.h>
26 #include <string.h>
27 #include <wchar.h>
28 #include <wcsmbsload.h>
29 
30 #include <sysdep.h>
31 
32 #ifndef EILSEQ
33 # define EILSEQ EINVAL
34 #endif
35 
36 
37 size_t
38 attribute_hidden
__mbsrtowcs_l(wchar_t * dst,const char ** src,size_t len,mbstate_t * ps,locale_t l)39 __mbsrtowcs_l (wchar_t *dst, const char **src, size_t len, mbstate_t *ps,
40 	       locale_t l)
41 {
42   struct __gconv_step_data data;
43   size_t result;
44   int status;
45   struct __gconv_step *towc;
46   size_t non_reversible;
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;
54 
55   /* Get the conversion functions.  */
56   fcts = get_gconv_fcts (l->__locales[LC_CTYPE]);
57 
58   /* Get the structure with the function pointers.  */
59   towc = fcts->towc;
60   __gconv_fct fct = towc->__fct;
61 #ifdef PTR_DEMANGLE
62   if (towc->__shlib_handle != NULL)
63     PTR_DEMANGLE (fct);
64 #endif
65 
66   /* We have to handle DST == NULL special.  */
67   if (dst == NULL)
68     {
69       mbstate_t temp_state;
70       wchar_t buf[64];		/* Just an arbitrary size.  */
71       const unsigned char *inbuf = (const unsigned char *) *src;
72       const unsigned char *srcend = inbuf + strlen (*src) + 1;
73 
74       temp_state = *data.__statep;
75       data.__statep = &temp_state;
76 
77       result = 0;
78       data.__outbufend = (unsigned char *) buf + sizeof (buf);
79       do
80 	{
81 	  data.__outbuf = (unsigned char *) buf;
82 
83 	  status = DL_CALL_FCT (fct, (towc, &data, &inbuf, srcend, NULL,
84 				      &non_reversible, 0, 1));
85 
86 	  result += (wchar_t *) data.__outbuf - buf;
87 	}
88       while (status == __GCONV_FULL_OUTPUT);
89 
90       if (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
91 	{
92 	  /* There better should be a NUL wide char at the end.  */
93 	  assert (((wchar_t *) data.__outbuf)[-1] == L'\0');
94 	  /* Don't count the NUL character in.  */
95 	  --result;
96 	}
97     }
98   else
99     {
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       const unsigned char *srcp = (const unsigned char *) *src;
104       const unsigned char *srcend;
105 
106       data.__outbuf = (unsigned char *) dst;
107       data.__outbufend = data.__outbuf + len * sizeof (wchar_t);
108 
109       status = __GCONV_FULL_OUTPUT;
110 
111       while (len > 0)
112 	{
113 	  /* Pessimistic guess as to how much input we can use.  In the
114 	     worst case we need one input byte for one output wchar_t.  */
115 	  srcend = srcp + __strnlen ((const char *) srcp, len) + 1;
116 
117 	  status = DL_CALL_FCT (fct, (towc, &data, &srcp, srcend, NULL,
118 				      &non_reversible, 0, 1));
119 	  if ((status != __GCONV_EMPTY_INPUT
120 	       && status != __GCONV_INCOMPLETE_INPUT)
121 	      /* Not all input read.  */
122 	      || srcp != srcend
123 	      /* Reached the end of the input.  */
124 	      || srcend[-1] == '\0')
125 	    break;
126 
127 	  len = (wchar_t *) data.__outbufend - (wchar_t *) data.__outbuf;
128 	}
129 
130       /* Make the end if the input known to the caller.  */
131       *src = (const char *) srcp;
132 
133       result = (wchar_t *) data.__outbuf - dst;
134 
135       /* We have to determine whether the last character converted
136 	 is the NUL character.  */
137       if ((status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
138 	  && ((wchar_t *) dst)[result - 1] == L'\0')
139 	{
140 	  assert (result > 0);
141 	  assert (__mbsinit (data.__statep));
142 	  *src = NULL;
143 	  --result;
144 	}
145     }
146 
147   /* There must not be any problems with the conversion but illegal input
148      characters.  */
149   assert (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT
150 	  || status == __GCONV_ILLEGAL_INPUT
151 	  || status == __GCONV_INCOMPLETE_INPUT
152 	  || status == __GCONV_FULL_OUTPUT);
153 
154   if (status != __GCONV_OK && status != __GCONV_FULL_OUTPUT
155       && status != __GCONV_EMPTY_INPUT && status != __GCONV_INCOMPLETE_INPUT)
156     {
157       result = (size_t) -1;
158       __set_errno (EILSEQ);
159     }
160 
161   return result;
162 }
163