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 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 <dlfcn.h>
  21 #include <errno.h>
  22 #include <gconv.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <wchar.h>
  26 #include <wcsmbsload.h>
  27
  28 #include <assert.h>
  29
  30 #ifndef EILSEQ
  31 # define EILSEQ EINVAL
  32 #endif
  33
  34
  35 /* This is the private state used if PS is NULL.  */
  36 static mbstate_t state;
  37
  38 size_t
  39 __mbsrtowcs (dst, src, len, ps)
  40      wchar_t *dst;
  41      const char **src;
  42      size_t len;
  43      mbstate_t *ps;
  44 {
  45   struct __gconv_step_data data;
  46   size_t result;
  47   int status;
  48   struct __gconv_step *towc;
  49   size_t non_reversible;
  50
  51   /* Tell where we want the result.  */
  52   data.__invocation_counter = 0;
  53   data.__internal_use = 1;
  54   data.__flags = __GCONV_IS_LAST;
  55   data.__statep = ps ?: &state;
  56   data.__trans = NULL;
  57
  58   /* Make sure we use the correct function.  */
  59   update_conversion_ptrs ();
  60
  61   /* Get the structure with the function pointers.  */
  62   towc = __wcsmbs_gconv_fcts.towc;
  63
  64   /* We have to handle DST == NULL special.  */
  65   if (dst == NULL)
  66     {
  67       mbstate_t temp_state;
  68       wchar_t buf[64];          /* Just an arbitrary size.  */
  69       const unsigned char *inbuf = (const unsigned char *) *src;
  70       const unsigned char *srcend = inbuf + strlen (inbuf) + 1;
  71
  72       temp_state = *data.__statep;
  73       data.__statep = &temp_state;
  74
  75       result = 0;
  76       data.__outbufend = (char *) buf + sizeof (buf);
  77       do
  78         {
  79           data.__outbuf = (char *) buf;
  80
  81           status = DL_CALL_FCT (towc->__fct,
  82                                 (towc, &data, &inbuf, srcend, NULL,
  83                                  &non_reversible, 0, 1));
  84
  85           result += (wchar_t *) data.__outbuf - buf;
  86         }
  87       while (status == __GCONV_FULL_OUTPUT);
  88
  89       if (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
  90         {
  91           /* There better should be a NUL wide char at the end.  */
  92           assert (((wchar_t *) data.__outbuf)[-1] == L'\0');
  93           /* Don't count the NUL character in.  */
  94           --result;
  95         }
  96     }
  97   else
  98     {
  99       /* This code is based on the safe assumption that all internal
 100          multi-byte encodings use the NUL byte only to mark the end
 101          of the string.  */
 102       const unsigned char *srcend;
 103
 104       srcend = (const unsigned char *) (*src
 105                                         + __strnlen (*src, len * MB_CUR_MAX)
 106                                         + 1);
 107
 108       data.__outbuf = (unsigned char *) dst;
 109       data.__outbufend = data.__outbuf + len * sizeof (wchar_t);
 110
 111       status = DL_CALL_FCT (towc->__fct,
 112                             (towc, &data, (const unsigned char **) src, srcend,
 113                              NULL, &non_reversible, 0, 1));
 114
 115       result = (wchar_t *) data.__outbuf - dst;
 116
 117       /* We have to determine whether the last character converted
 118          is the NUL character.  */
 119       if ((status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
 120           && ((wchar_t *) dst)[result - 1] == L'\0')
 121         {
 122           assert (result > 0);
 123           assert (__mbsinit (data.__statep));
 124           *src = NULL;
 125           --result;
 126         }
 127     }
 128
 129   /* There must not be any problems with the conversion but illegal input
 130      characters.  */
 131   assert (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT
 132           || status == __GCONV_ILLEGAL_INPUT
 133           || status == __GCONV_INCOMPLETE_INPUT
 134           || status == __GCONV_FULL_OUTPUT);
 135
 136   if (status != __GCONV_OK && status != __GCONV_FULL_OUTPUT
 137       && status != __GCONV_EMPTY_INPUT && status != __GCONV_INCOMPLETE_INPUT)
 138     {
 139       result = (size_t) -1;
 140       __set_errno (EILSEQ);
 141     }
 142
 143   return result;
 144 }
 145 weak_alias (__mbsrtowcs, mbsrtowcs)