wcsmbs/wcsrtombs.c

   1 /* Copyright (C) 1996-2015 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, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <assert.h>
  20 #include <dlfcn.h>
  21 #include <errno.h>
  22 #include <stdlib.h>
  23 #include <gconv.h>
  24 #include <wchar.h>
  25 #include <wcsmbsload.h>
  26
  27 #include <sysdep.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 __wcsrtombs (dst, src, len, ps)
  39      char *dst;
  40      const wchar_t **src;
  41      size_t len;
  42      mbstate_t *ps;
  43 {
  44   struct __gconv_step_data data;
  45   int status;
  46   size_t result;
  47   struct __gconv_step *tomb;
  48   const struct gconv_fcts *fcts;
  49
  50   /* Tell where we want the result.  */
  51   data.__invocation_counter = 0;
  52   data.__internal_use = 1;
  53   data.__flags = __GCONV_IS_LAST;
  54   data.__statep = ps ?: &state;
  55
  56   /* Get the conversion functions.  */
  57   fcts = get_gconv_fcts (_NL_CURRENT_DATA (LC_CTYPE));
  58
  59   /* Get the structure with the function pointers.  */
  60   tomb = fcts->tomb;
  61   __gconv_fct fct = tomb->__fct;
  62 #ifdef PTR_DEMANGLE
  63   if (tomb->__shlib_handle != NULL)
  64     PTR_DEMANGLE (fct);
  65 #endif
  66
  67   /* We have to handle DST == NULL special.  */
  68   if (dst == NULL)
  69     {
  70       mbstate_t temp_state;
  71       unsigned char buf[256];           /* Just an arbitrary value.  */
  72       const wchar_t *srcend = *src + __wcslen (*src) + 1;
  73       const unsigned char *inbuf = (const unsigned char *) *src;
  74       size_t dummy;
  75
  76       temp_state = *data.__statep;
  77       data.__statep = &temp_state;
  78
  79       result = 0;
  80       data.__outbufend = buf + sizeof (buf);
  81
  82       do
  83         {
  84           data.__outbuf = buf;
  85
  86           status = DL_CALL_FCT (fct, (tomb, &data, &inbuf,
  87                                       (const unsigned char *) srcend, NULL,
  88                                       &dummy, 0, 1));
  89
  90           /* Count the number of bytes.  */
  91           result += data.__outbuf - buf;
  92         }
  93       while (status == __GCONV_FULL_OUTPUT);
  94
  95       if (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
  96         {
  97           /* There better should be a NUL byte at the end.  */
  98           assert (data.__outbuf[-1] == '\0');
  99           /* Don't count the NUL character in.  */
 100           --result;
 101         }
 102     }
 103   else
 104     {
 105       /* This code is based on the safe assumption that all internal
 106          multi-byte encodings use the NUL byte only to mark the end
 107          of the string.  */
 108       const wchar_t *srcend = *src + __wcsnlen (*src, len) + 1;
 109       size_t dummy;
 110
 111       data.__outbuf = (unsigned char *) dst;
 112       data.__outbufend = (unsigned char *) dst + len;
 113
 114       status = DL_CALL_FCT (fct, (tomb, &data, (const unsigned char **) src,
 115                                   (const unsigned char *) srcend, NULL,
 116                                   &dummy, 0, 1));
 117
 118       /* Count the number of bytes.  */
 119       result = data.__outbuf - (unsigned char *) dst;
 120
 121       /* We have to determine whether the last character converted
 122          is the NUL character.  */
 123       if ((status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
 124           && data.__outbuf[-1] == '\0')
 125         {
 126           assert (data.__outbuf != (unsigned char *) dst);
 127           assert (__mbsinit (data.__statep));
 128           *src = NULL;
 129           --result;
 130         }
 131     }
 132
 133   /* There must not be any problems with the conversion but illegal input
 134      characters.  */
 135   assert (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT
 136           || status == __GCONV_ILLEGAL_INPUT
 137           || status == __GCONV_INCOMPLETE_INPUT
 138           || status == __GCONV_FULL_OUTPUT);
 139
 140   if (status != __GCONV_OK && status != __GCONV_FULL_OUTPUT
 141       && status != __GCONV_EMPTY_INPUT)
 142     {
 143       result = (size_t) -1;
 144       __set_errno (EILSEQ);
 145     }
 146
 147   return result;
 148 }
 149 weak_alias (__wcsrtombs, wcsrtombs)