wcsmbs/wcsrtombs.c

   1 /* Copyright (C) 1996, 1997, 1998 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 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 <stdlib.h>
  22 #include <gconv.h>
  23 #include <wchar.h>
  24 #include <wcsmbsload.h>
  25
  26 #include <assert.h>
  27
  28 #ifndef EILSEQ
  29 # define EILSEQ EINVAL
  30 #endif
  31
  32
  33 /* This is the private state used if PS is NULL.  */
  34 static mbstate_t state;
  35
  36 size_t
  37 __wcsrtombs (dst, src, len, ps)
  38      char *dst;
  39      const wchar_t **src;
  40      size_t len;
  41      mbstate_t *ps;
  42 {
  43   struct gconv_step_data data;
  44   int status;
  45   size_t result;
  46
  47   /* Tell where we want the result.  */
  48   data.invocation_counter = 0;
  49   data.internal_use = 1;
  50   data.is_last = 1;
  51   data.statep = ps ?: &state;
  52
  53   /* Make sure we use the correct function.  */
  54   update_conversion_ptrs ();
  55
  56   /* We have to handle DST == NULL special.  */
  57   if (dst == NULL)
  58     {
  59       char buf[256];            /* Just an arbitrary value.  */
  60       const wchar_t *srcend = *src + __wcslen (*src) + 1;
  61       const wchar_t *inbuf = *src;
  62       size_t dummy;
  63
  64       result = 0;
  65       data.outbufend = buf + sizeof (buf);
  66
  67       do
  68         {
  69           data.outbuf = buf;
  70
  71           status = (*__wcsmbs_gconv_fcts.tomb->fct) (__wcsmbs_gconv_fcts.tomb,
  72                                                      &data,
  73                                                      (const char **) &inbuf,
  74                                                      (const char *) srcend,
  75                                                      &dummy, 0);
  76
  77           /* Count the number of bytes.  */
  78           result += 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 byte at the end.  */
  85           assert (data.outbuf[-1] == '\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 wchar_t *srcend = *src + __wcsnlen (*src, len * MB_CUR_MAX) + 1;
  96       size_t dummy;
  97
  98       data.outbuf = dst;
  99       data.outbufend = dst + len;
 100
 101       status = (*__wcsmbs_gconv_fcts.tomb->fct) (__wcsmbs_gconv_fcts.tomb,
 102                                                  &data, (const char **) src,
 103                                                  (const char *) srcend,
 104                                                  &dummy, 0);
 105
 106       /* Count the number of bytes.  */
 107       result = data.outbuf - dst;
 108
 109       /* We have to determine whether the last character converted
 110          is the NUL character.  */
 111       if ((status == GCONV_OK || status == GCONV_EMPTY_INPUT
 112            || status == GCONV_FULL_OUTPUT)
 113           && data.outbuf[-1] == '\0')
 114         {
 115           assert (data.outbuf != dst);
 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 || status == GCONV_FULL_OUTPUT);
 127
 128   if (status != GCONV_OK && status != GCONV_FULL_OUTPUT
 129       && status != GCONV_EMPTY_INPUT)
 130     {
 131       result = (size_t) -1;
 132       __set_errno (EILSEQ);
 133     }
 134
 135   return result;
 136 }
 137 weak_alias (__wcsrtombs, wcsrtombs)