wcsmbs/mbsrtowcs_l.c

   1 /* Copyright (C) 2002-2015 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@gnu.org>, 2002.
   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    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <assert.h>
  20 #include <ctype.h>
  21 #include <string.h>
  22 #include "wcsmbsload.h"
  23 #include <dlfcn.h>
  24 #include <errno.h>
  25 #include <gconv.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28 #include <wchar.h>
  29 #include <wcsmbsload.h>
  30
  31 #include <sysdep.h>
  32
  33 #ifndef EILSEQ
  34 # define EILSEQ EINVAL
  35 #endif
  36
  37
  38 size_t
  39 attribute_hidden
  40 __mbsrtowcs_l (dst, src, len, ps, l)
  41      wchar_t *dst;
  42      const char **src;
  43      size_t len;
  44      mbstate_t *ps;
  45      __locale_t l;
  46 {
  47   struct __gconv_step_data data;
  48   size_t result;
  49   int status;
  50   struct __gconv_step *towc;
  51   size_t non_reversible;
  52   const struct gconv_fcts *fcts;
  53
  54   /* Tell where we want the result.  */
  55   data.__invocation_counter = 0;
  56   data.__internal_use = 1;
  57   data.__flags = __GCONV_IS_LAST;
  58   data.__statep = ps;
  59
  60   /* Get the conversion functions.  */
  61   fcts = get_gconv_fcts (l->__locales[LC_CTYPE]);
  62
  63   /* Get the structure with the function pointers.  */
  64   towc = fcts->towc;
  65   __gconv_fct fct = towc->__fct;
  66 #ifdef PTR_DEMANGLE
  67   if (towc->__shlib_handle != NULL)
  68     PTR_DEMANGLE (fct);
  69 #endif
  70
  71   /* We have to handle DST == NULL special.  */
  72   if (dst == NULL)
  73     {
  74       mbstate_t temp_state;
  75       wchar_t buf[64];          /* Just an arbitrary size.  */
  76       const unsigned char *inbuf = (const unsigned char *) *src;
  77       const unsigned char *srcend = inbuf + strlen (*src) + 1;
  78
  79       temp_state = *data.__statep;
  80       data.__statep = &temp_state;
  81
  82       result = 0;
  83       data.__outbufend = (unsigned char *) buf + sizeof (buf);
  84       do
  85         {
  86           data.__outbuf = (unsigned char *) buf;
  87
  88           status = DL_CALL_FCT (fct, (towc, &data, &inbuf, srcend, NULL,
  89                                       &non_reversible, 0, 1));
  90
  91           result += (wchar_t *) data.__outbuf - buf;
  92         }
  93       while (status == __GCONV_FULL_OUTPUT);
  94
  95       if (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
  96         {
  97           /* There better should be a NUL wide char at the end.  */
  98           assert (((wchar_t *) data.__outbuf)[-1] == L'\0');
  99           /* Don't count the NUL character in.  */
 100           --result;
 101         }
 102     }
 103   else
 104     {
 105       /* This code is based on the safe assumption that all internal
 106          multi-byte encodings use the NUL byte only to mark the end
 107          of the string.  */
 108       const unsigned char *srcp = (const unsigned char *) *src;
 109       const unsigned char *srcend;
 110
 111       data.__outbuf = (unsigned char *) dst;
 112       data.__outbufend = data.__outbuf + len * sizeof (wchar_t);
 113
 114       status = __GCONV_FULL_OUTPUT;
 115
 116       while (len > 0)
 117         {
 118           /* Pessimistic guess as to how much input we can use.  In the
 119              worst case we need one input byte for one output wchar_t.  */
 120           srcend = srcp + __strnlen ((const char *) srcp, len) + 1;
 121
 122           status = DL_CALL_FCT (fct, (towc, &data, &srcp, srcend, NULL,
 123                                       &non_reversible, 0, 1));
 124           if ((status != __GCONV_EMPTY_INPUT
 125                && status != __GCONV_INCOMPLETE_INPUT)
 126               /* Not all input read.  */
 127               || srcp != srcend
 128               /* Reached the end of the input.  */
 129               || srcend[-1] == '\0')
 130             break;
 131
 132           len = (wchar_t *) data.__outbufend - (wchar_t *) data.__outbuf;
 133         }
 134
 135       /* Make the end if the input known to the caller.  */
 136       *src = (const char *) srcp;
 137
 138       result = (wchar_t *) data.__outbuf - dst;
 139
 140       /* We have to determine whether the last character converted
 141          is the NUL character.  */
 142       if ((status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
 143           && ((wchar_t *) dst)[result - 1] == L'\0')
 144         {
 145           assert (result > 0);
 146           assert (__mbsinit (data.__statep));
 147           *src = NULL;
 148           --result;
 149         }
 150     }
 151
 152   /* There must not be any problems with the conversion but illegal input
 153      characters.  */
 154   assert (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT
 155           || status == __GCONV_ILLEGAL_INPUT
 156           || status == __GCONV_INCOMPLETE_INPUT
 157           || status == __GCONV_FULL_OUTPUT);
 158
 159   if (status != __GCONV_OK && status != __GCONV_FULL_OUTPUT
 160       && status != __GCONV_EMPTY_INPUT && status != __GCONV_INCOMPLETE_INPUT)
 161     {
 162       result = (size_t) -1;
 163       __set_errno (EILSEQ);
 164     }
 165
 166   return result;
 167 }