libstdc++-v3/config/io/c_io_libio_codecvt.c

   1 /* Copyright (C) 2000 Free Software Foundation, Inc.
   2    This file is part of the GNU IO Library.
   3
   4    This library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU General Public License as
   6    published by the Free Software Foundation; either version 2, or (at
   7    your option) any later version.
   8
   9    This library is distributed in the hope that it will be useful, but
  10    WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this library; see the file COPYING.  If not, write to
  16    the Free Software Foundation, 59 Temple Place - Suite 330, Boston,
  17    MA 02111-1307, USA.
  18
  19    As a special exception, if you link this library with files
  20    compiled with a GNU compiler to produce an executable, this does
  21    not cause the resulting executable to be covered by the GNU General
  22    Public License.  This exception does not however invalidate any
  23    other reasons why the executable file might be covered by the GNU
  24    General Public License.  */
  25
  26 /* Slightly modified from glibc/libio/iofwide.c */
  27
  28 #include <libio.h>
  29
  30 #ifdef _GLIBCPP_USE_WCHAR_T
  31
  32 /* Prototypes of libio's codecvt functions.  */
  33 static enum __codecvt_result
  34 do_out(struct _IO_codecvt *codecvt, __c_mbstate_t *statep,
  35        const wchar_t *from_start, const wchar_t *from_end,
  36        const wchar_t **from_stop, char *to_start, char *to_end,
  37        char **to_stop);
  38
  39 static enum __codecvt_result
  40 do_unshift(struct _IO_codecvt *codecvt, __c_mbstate_t *statep, char *to_start,
  41            char *to_end, char **to_stop);
  42
  43 static enum __codecvt_result
  44 do_in(struct _IO_codecvt *codecvt, __c_mbstate_t *statep,
  45       const char *from_start, const char *from_end, const char **from_stop,
  46       wchar_t *to_start, wchar_t *to_end, wchar_t **to_stop);
  47
  48 static int
  49 do_encoding(struct _IO_codecvt *codecvt);
  50
  51 static int
  52 do_length(struct _IO_codecvt *codecvt, __c_mbstate_t *statep,
  53           const char *from_start, const char *from_end, _IO_size_t max);
  54
  55 static int
  56 do_max_length(struct _IO_codecvt *codecvt);
  57
  58 static int
  59 do_always_noconv(struct _IO_codecvt *codecvt);
  60
  61
  62 /* The functions used in `codecvt' for libio are always the same.  */
  63 struct _IO_codecvt __c_libio_codecvt =
  64 {
  65   .__codecvt_destr = NULL,              /* Destructor, never used.  */
  66   .__codecvt_do_out = do_out,
  67   .__codecvt_do_unshift = do_unshift,
  68   .__codecvt_do_in = do_in,
  69   .__codecvt_do_encoding = do_encoding,
  70   .__codecvt_do_always_noconv = do_always_noconv,
  71   .__codecvt_do_length = do_length,
  72   .__codecvt_do_max_length = do_max_length
  73 };
  74
  75 static enum __codecvt_result
  76 do_out(struct _IO_codecvt *codecvt, __c_mbstate_t *statep,
  77        const wchar_t *from_start, const wchar_t *from_end,
  78        const wchar_t **from_stop, char *to_start, char *to_end,
  79        char **to_stop)
  80 {
  81   enum __codecvt_result res = __codecvt_ok;
  82
  83   while (from_start < from_end)
  84     {
  85       if (to_start >= to_end)
  86         {
  87           res = __codecvt_partial;
  88           break;
  89         }
  90       *to_start++ = (char) *from_start++;
  91     }
  92
  93   *from_stop = from_start;
  94   *to_stop = to_start;
  95
  96   return res;
  97 }
  98
  99
 100 static enum __codecvt_result
 101 do_unshift(struct _IO_codecvt *codecvt, __c_mbstate_t *statep,
 102            char *to_start, char *to_end, char **to_stop)
 103 {
 104   *to_stop = to_start;
 105   return __codecvt_ok;
 106 }
 107
 108
 109 static enum __codecvt_result
 110 do_in(struct _IO_codecvt *codecvt, __c_mbstate_t *statep,
 111       const char *from_start, const char *from_end, const char **from_stop,
 112       wchar_t *to_start, wchar_t *to_end, wchar_t **to_stop)
 113 {
 114   enum __codecvt_result res = __codecvt_ok;
 115
 116   while (from_start < from_end)
 117     {
 118       if (to_start >= to_end)
 119         {
 120           res = __codecvt_partial;
 121           break;
 122         }
 123       *to_start++ = (wchar_t) *from_start++;
 124     }
 125
 126   *from_stop = from_start;
 127   *to_stop = to_start;
 128
 129   return res;
 130 }
 131
 132
 133 static int
 134 do_encoding(struct _IO_codecvt *codecvt)
 135 { return 1; }
 136
 137
 138 static int
 139 do_always_noconv(struct _IO_codecvt *codecvt)
 140 { return 0; }
 141
 142
 143 static int
 144 do_length(struct _IO_codecvt *codecvt, __c_mbstate_t *statep,
 145           const char *from_start, const char *from_end, _IO_size_t max)
 146 { return from_end - from_start; }
 147
 148
 149 static int
 150 do_max_length(struct _IO_codecvt *codecvt)
 151 { return 1; }
 152
 153 #endif /* _GLIBCPP_USE_WCHAR_T */