wcsmbs/mbsrtowcs.c

   1 /* Copyright (C) 1996, 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@gnu.org>, 1996.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Library General Public License as
   7    published by the Free Software Foundation; either version 2 of the
   8    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    Library General Public License for more details.
  14
  15    You should have received a copy of the GNU Library General Public
  16    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  17    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  18    Boston, MA 02111-1307, USA.  */
  19
  20 #include <errno.h>
  21 #include <gconv.h>
  22 #include <stdlib.h>
  23 #include <string.h>
  24 #include <wchar.h>
  25 #include <wcsmbsload.h>
  26
  27 #include <assert.h>
  28
  29 #ifndef EILSEQ
  30 # define EILSEQ EINVAL
  31 #endif
  32
  33
  34 /* This is the private state used if PS is NULL.  */
  35 static mbstate_t state;
  36
  37 size_t
  38 __mbsrtowcs (dst, src, len, ps)
  39      wchar_t *dst;
  40      const char **src;
  41      size_t len;
  42      mbstate_t *ps;
  43 {
  44   struct __gconv_step_data data;
  45   size_t result;
  46   int status;
  47   struct __gconv_step *towc;
  48   size_t non_reversible;
  49
  50   /* Tell where we want the result.  */
  51   data.__invocation_counter = 0;
  52   data.__internal_use = 1;
  53   data.__is_last = 1;
  54   data.__statep = ps ?: &state;
  55
  56   /* Make sure we use the correct function.  */
  57   update_conversion_ptrs ();
  58
  59   /* Get the structure with the function pointers.  */
  60   towc = __wcsmbs_gconv_fcts.towc;
  61
  62   /* We have to handle DST == NULL special.  */
  63   if (dst == NULL)
  64     {
  65       mbstate_t temp_state;
  66       wchar_t buf[64];          /* Just an arbitrary size.  */
  67       const unsigned char *inbuf = (const unsigned char *) *src;
  68       const unsigned char *srcend = inbuf + strlen (inbuf) + 1;
  69
  70       temp_state = *data.__statep;
  71       data.__statep = &temp_state;
  72
  73       result = 0;
  74       data.__outbufend = (char *) buf + sizeof (buf);
  75       do
  76         {
  77           data.__outbuf = (char *) buf;
  78
  79           status = (*towc->__fct) (__wcsmbs_gconv_fcts.towc, &data, &inbuf,
  80                                    srcend, &non_reversible, 0, 1);
  81
  82           result += (wchar_t *) data.__outbuf - buf;
  83         }
  84       while (status == __GCONV_FULL_OUTPUT);
  85
  86       if (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
  87         {
  88           /* There better should be a NUL wide char at the end.  */
  89           assert (((wchar_t *) data.__outbuf)[-1] == L'\0');
  90           /* Don't count the NUL character in.  */
  91           --result;
  92         }
  93     }
  94   else
  95     {
  96       /* This code is based on the safe assumption that all internal
  97          multi-byte encodings use the NUL byte only to mark the end
  98          of the string.  */
  99       const unsigned char *srcend;
 100
 101       srcend = (const unsigned char *) (*src
 102                                         + __strnlen (*src, len * MB_CUR_MAX)
 103                                         + 1);
 104
 105       data.__outbuf = (unsigned char *) dst;
 106       data.__outbufend = data.__outbuf + len * sizeof (wchar_t);
 107
 108       status = (*towc->__fct) (__wcsmbs_gconv_fcts.towc, &data,
 109                                (const unsigned char **) src, srcend,
 110                                &non_reversible, 0, 1);
 111
 112       result = (wchar_t *) data.__outbuf - dst;
 113
 114       /* We have to determine whether the last character converted
 115          is the NUL character.  */
 116       if ((status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
 117           && ((wchar_t *) dst)[result - 1] == L'\0')
 118         {
 119           assert (result > 0);
 120           assert (__mbsinit (data.__statep));
 121           *src = NULL;
 122           --result;
 123         }
 124     }
 125
 126   /* There must not be any problems with the conversion but illegal input
 127      characters.  */
 128   assert (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT
 129           || status == __GCONV_ILLEGAL_INPUT
 130           || status == __GCONV_INCOMPLETE_INPUT
 131           || status == __GCONV_FULL_OUTPUT);
 132
 133   if (status != __GCONV_OK && status != __GCONV_FULL_OUTPUT
 134       && status != __GCONV_EMPTY_INPUT && status != __GCONV_INCOMPLETE_INPUT)
 135     {
 136       result = (size_t) -1;
 137       __set_errno (EILSEQ);
 138     }
 139
 140   return result;
 141 }
 142 weak_alias (__mbsrtowcs, mbsrtowcs)