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       wchar_t buf[64];          /* Just an arbitrary size.  */
  66       const unsigned char *inbuf = (const unsigned char *) *src;
  67       const unsigned char *srcend = inbuf + strlen (inbuf) + 1;
  68
  69       result = 0;
  70       data.__outbufend = (char *) buf + sizeof (buf);
  71       do
  72         {
  73           data.__outbuf = (char *) buf;
  74
  75           status = (*towc->__fct) (__wcsmbs_gconv_fcts.towc, &data, &inbuf,
  76                                    srcend, &non_reversible, 0);
  77
  78           result += (wchar_t *) data.__outbuf - buf;
  79         }
  80       while (status == __GCONV_FULL_OUTPUT);
  81
  82       if (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
  83         {
  84           /* There better should be a NUL wide char at the end.  */
  85           assert (((wchar_t *) data.__outbuf)[-1] == L'\0');
  86           /* Don't count the NUL character in.  */
  87           --result;
  88         }
  89     }
  90   else
  91     {
  92       /* This code is based on the safe assumption that all internal
  93          multi-byte encodings use the NUL byte only to mark the end
  94          of the string.  */
  95       const unsigned char *srcend;
  96
  97       srcend = (const unsigned char *) (*src
  98                                         + __strnlen (*src, len * MB_CUR_MAX)
  99                                         + 1);
 100
 101       data.__outbuf = (unsigned char *) dst;
 102       data.__outbufend = data.__outbuf + len * sizeof (wchar_t);
 103
 104       status = (*towc->__fct) (__wcsmbs_gconv_fcts.towc, &data,
 105                                (const unsigned char **) src, srcend,
 106                                &non_reversible, 0);
 107
 108       result = (wchar_t *) data.__outbuf - dst;
 109
 110       /* We have to determine whether the last character converted
 111          is the NUL character.  */
 112       if ((status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
 113           && ((wchar_t *) dst)[result - 1] == L'\0')
 114         {
 115           assert (result > 0);
 116           assert (__mbsinit (data.__statep));
 117           *src = NULL;
 118           --result;
 119         }
 120     }
 121
 122   /* There must not be any problems with the conversion but illegal input
 123      characters.  */
 124   assert (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT
 125           || status == __GCONV_ILLEGAL_INPUT
 126           || status == __GCONV_INCOMPLETE_INPUT
 127           || status == __GCONV_FULL_OUTPUT);
 128
 129   if (status != __GCONV_OK && status != __GCONV_FULL_OUTPUT
 130       && status != __GCONV_EMPTY_INPUT)
 131     {
 132       result = (size_t) -1;
 133       __set_errno (EILSEQ);
 134     }
 135
 136   return result;
 137 }
 138 weak_alias (__mbsrtowcs, mbsrtowcs)