wcsmbs/mbsrtowcs_l.c

   1 /* Copyright (C) 2002, 2004, 2005 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, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include <assert.h>
  21 #include <ctype.h>
  22 #include <string.h>
  23 #include "wcsmbsload.h"
  24 #include <dlfcn.h>
  25 #include <errno.h>
  26 #include <gconv.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29 #include <wchar.h>
  30 #include <wcsmbsload.h>
  31
  32 #include <sysdep.h>
  33
  34 #ifndef EILSEQ
  35 # define EILSEQ EINVAL
  36 #endif
  37
  38
  39 size_t
  40 attribute_hidden
  41 __mbsrtowcs_l (dst, src, len, ps, l)
  42      wchar_t *dst;
  43      const char **src;
  44      size_t len;
  45      mbstate_t *ps;
  46      __locale_t l;
  47 {
  48   struct __gconv_step_data data;
  49   size_t result;
  50   int status;
  51   struct __gconv_step *towc;
  52   size_t non_reversible;
  53   const struct gconv_fcts *fcts;
  54
  55   /* Tell where we want the result.  */
  56   data.__invocation_counter = 0;
  57   data.__internal_use = 1;
  58   data.__flags = __GCONV_IS_LAST;
  59   data.__statep = ps;
  60   data.__trans = NULL;
  61
  62   /* Get the conversion functions.  */
  63   fcts = get_gconv_fcts (l->__locales[LC_CTYPE]);
  64
  65   /* Get the structure with the function pointers.  */
  66   towc = fcts->towc;
  67   __gconv_fct fct = towc->__fct;
  68 #ifdef PTR_DEMANGLE
  69   if (towc->__shlib_handle != NULL)
  70     PTR_DEMANGLE (fct);
  71 #endif
  72
  73   /* We have to handle DST == NULL special.  */
  74   if (dst == NULL)
  75     {
  76       mbstate_t temp_state;
  77       wchar_t buf[64];          /* Just an arbitrary size.  */
  78       const unsigned char *inbuf = (const unsigned char *) *src;
  79       const unsigned char *srcend = inbuf + strlen (*src) + 1;
  80
  81       temp_state = *data.__statep;
  82       data.__statep = &temp_state;
  83
  84       result = 0;
  85       data.__outbufend = (unsigned char *) buf + sizeof (buf);
  86       do
  87         {
  88           data.__outbuf = (unsigned char *) buf;
  89
  90           status = DL_CALL_FCT (fct, (towc, &data, &inbuf, srcend, NULL,
  91                                       &non_reversible, 0, 1));
  92
  93           result += (wchar_t *) data.__outbuf - buf;
  94         }
  95       while (status == __GCONV_FULL_OUTPUT);
  96
  97       if (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
  98         {
  99           /* There better should be a NUL wide char at the end.  */
 100           assert (((wchar_t *) data.__outbuf)[-1] == L'\0');
 101           /* Don't count the NUL character in.  */
 102           --result;
 103         }
 104     }
 105   else
 106     {
 107       /* This code is based on the safe assumption that all internal
 108          multi-byte encodings use the NUL byte only to mark the end
 109          of the string.  */
 110       const unsigned char *srcp = (const unsigned char *) *src;
 111       const unsigned char *srcend;
 112
 113       data.__outbuf = (unsigned char *) dst;
 114       data.__outbufend = data.__outbuf + len * sizeof (wchar_t);
 115
 116       status = __GCONV_FULL_OUTPUT;
 117
 118       while (len > 0)
 119         {
 120           /* Pessimistic guess as to how much input we can use.  In the
 121              worst case we need one input byte for one output wchar_t.  */
 122           srcend = srcp + __strnlen ((const char *) srcp, len) + 1;
 123
 124           status = DL_CALL_FCT (fct, (towc, &data, &srcp, srcend, NULL,
 125                                       &non_reversible, 0, 1));
 126           if ((status != __GCONV_EMPTY_INPUT
 127                && status != __GCONV_INCOMPLETE_INPUT)
 128               /* Not all input read.  */
 129               || srcp != srcend
 130               /* Reached the end of the input.  */
 131               || srcend[-1] == '\0')
 132             break;
 133
 134           len = (wchar_t *) data.__outbufend - (wchar_t *) data.__outbuf;
 135         }
 136
 137       /* Make the end if the input known to the caller.  */
 138       *src = (const char *) srcp;
 139
 140       result = (wchar_t *) data.__outbuf - dst;
 141
 142       /* We have to determine whether the last character converted
 143          is the NUL character.  */
 144       if ((status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
 145           && ((wchar_t *) dst)[result - 1] == L'\0')
 146         {
 147           assert (result > 0);
 148           assert (__mbsinit (data.__statep));
 149           *src = NULL;
 150           --result;
 151         }
 152     }
 153
 154   /* There must not be any problems with the conversion but illegal input
 155      characters.  */
 156   assert (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT
 157           || status == __GCONV_ILLEGAL_INPUT
 158           || status == __GCONV_INCOMPLETE_INPUT
 159           || status == __GCONV_FULL_OUTPUT);
 160
 161   if (status != __GCONV_OK && status != __GCONV_FULL_OUTPUT
 162       && status != __GCONV_EMPTY_INPUT && status != __GCONV_INCOMPLETE_INPUT)
 163     {
 164       result = (size_t) -1;
 165       __set_errno (EILSEQ);
 166     }
 167
 168   return result;
 169 }