iconvdata/iso-2022-kr.c

   1 /* Conversion module for ISO-2022-KR.
   2    Copyright (C) 1998 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Library General Public License as
   8    published by the Free Software Foundation; either version 2 of the
   9    License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Library General Public License for more details.
  15
  16    You should have received a copy of the GNU Library General Public
  17    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  18    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19    Boston, MA 02111-1307, USA.  */
  20
  21 #include <gconv.h>
  22 #include <stdint.h>
  23 #include <string.h>
  24 #include "ksc5601.h"
  25
  26 #include <assert.h>
  27
  28 /* This makes obvious what everybody knows: 0x1b is the Esc character.  */
  29 #define ESC     0x1b
  30
  31 /* The shift sequences for this charset (we it does not use ESC).  */
  32 #define SI      0x0f
  33 #define SO      0x0e
  34
  35 /* Definitions used in the body of the `gconv' function.  */
  36 #define CHARSET_NAME            "ISO-2022-KR//"
  37 #define DEFINE_INIT             1
  38 #define DEFINE_FINI             1
  39 #define FROM_LOOP               from_iso2022kr_loop
  40 #define TO_LOOP                 to_iso2022kr_loop
  41 #define MIN_NEEDED_FROM         1
  42 #define MAX_NEEDED_FROM         3
  43 #define MIN_NEEDED_TO           4
  44 #define MAX_NEEDED_TO           4
  45 #define PREPARE_LOOP \
  46   int save_set;                                                               \
  47   int set = data->statep->count;
  48 #define EXTRA_LOOP_ARGS         , set
  49
  50
  51 /* The COUNT element of the state keeps track of the currently selected
  52    character set.  The possible values are:  */
  53 enum
  54 {
  55   ASCII_set = 0,
  56   KSC5601_set
  57 };
  58
  59
  60 /* Since this is a stateful encoding we have to provide code which resets
  61    the output state to the initial state.  This has to be done during the
  62    flushing.  */
  63 #define EMIT_SHIFT_TO_INIT \
  64   if (data->statep->count != 0)                                               \
  65     {                                                                         \
  66       if (step->data == &from_object)                                         \
  67         /* It's easy, we don't have to emit anything, we just reset the       \
  68            state for the input.  */                                           \
  69         data->statep->count = 0;                                              \
  70       else                                                                    \
  71         {                                                                     \
  72           char *outbuf = data->outbuf;                                        \
  73                                                                               \
  74           /* We are not in the initial state.  To switch back we have         \
  75              to emit `SO'.  */                                                \
  76           if (outbuf == data->outbufend)                                      \
  77             /* We don't have enough room in the output buffer.  */            \
  78             status = GCONV_FULL_OUTPUT;                                       \
  79           else                                                                \
  80             {                                                                 \
  81               /* Write out the shift sequence.  */                            \
  82               *outbuf++ = SO;                                                 \
  83               data->outbuf = outbuf;                                          \
  84               data->statep->count = 0;                                        \
  85             }                                                                 \
  86         }                                                                     \
  87     }
  88
  89
  90 /* Since we might have to reset input pointer we must be able to save
  91    and retore the state.  */
  92 #define SAVE_RESET_STATE(Save) \
  93   if (Save)                                                                   \
  94     save_set = set;                                                           \
  95   else                                                                        \
  96     set = save_set
  97
  98
  99 /* First define the conversion function from ISO-2022-JP to UCS4.  */
 100 #define MIN_NEEDED_INPUT        MIN_NEEDED_FROM
 101 #define MAX_NEEDED_INPUT        MAX_NEEDED_FROM
 102 #define MIN_NEEDED_OUTPUT       MIN_NEEDED_TO
 103 #define LOOPFCT                 FROM_LOOP
 104 #define BODY \
 105   {                                                                           \
 106     uint32_t ch = *inptr;                                                     \
 107                                                                               \
 108     /* This is a 7bit character set, disallow all 8bit characters.  */        \
 109     if (ch > 0x7f)                                                            \
 110       {                                                                       \
 111         result = GCONV_ILLEGAL_INPUT;                                         \
 112         break;                                                                \
 113       }                                                                       \
 114                                                                               \
 115     /* Recognize escape sequences.  */                                        \
 116     if (ch == ESC)                                                            \
 117       {                                                                       \
 118         /* We don't really have to handle escape sequences since all the      \
 119            switching is done using the SI and SO bytes.  Butwe have to        \
 120            recognize `Esc $ ) C' since this is a kind of flag for this        \
 121            encoding.  We simply ignore it.  */                                \
 122         if (inptr + 1 > inend                                                 \
 123             || (inptr[1] == '$'                                               \
 124                 && (inptr + 2 > inend                                         \
 125                     || (inptr[2] == ')' && inptr + 3 > inend))))              \
 126                                                                               \
 127           {                                                                   \
 128             result = GCONV_EMPTY_INPUT;                                       \
 129             break;                                                            \
 130           }                                                                   \
 131         if (inptr[1] == '$' && inptr[2] == ')' && inptr[3] == 'C')            \
 132           {                                                                   \
 133             /* Yeah, yeah, we know this is ISO 2022-KR.  */                   \
 134             inptr += 4;                                                       \
 135             continue;                                                         \
 136           }                                                                   \
 137       }                                                                       \
 138     else if (ch == SI)                                                        \
 139       {                                                                       \
 140         /* Switch to use KSC.  */                                             \
 141         ++inptr;                                                              \
 142         set = KSC5601_set;                                                    \
 143         continue;                                                             \
 144       }                                                                       \
 145     else if (ch == SO)                                                        \
 146       {                                                                       \
 147         /* Switch to use ASCII.  */                                           \
 148         ++inptr;                                                              \
 149         set = ASCII_set;                                                      \
 150         continue;                                                             \
 151       }                                                                       \
 152                                                                               \
 153     if (set == ASCII_set || ch < 0x21 || ch == 0x7f)                          \
 154       /* Almost done, just advance the input pointer.  */                     \
 155       ++inptr;                                                                \
 156     else                                                                      \
 157       {                                                                       \
 158         assert (set == KSC5601_set);                                          \
 159                                                                               \
 160         /* Use the KSC 5601 table.  */                                        \
 161         ch = ksc5601_to_ucs4 (&inptr,                                         \
 162                               NEED_LENGTH_TEST ? inend - inptr : 2, 0);       \
 163                                                                               \
 164         if (NEED_LENGTH_TEST && ch == 0)                                      \
 165           {                                                                   \
 166             result = GCONV_EMPTY_INPUT;                                       \
 167             break;                                                            \
 168           }                                                                   \
 169         else if (ch == UNKNOWN_10646_CHAR)                                    \
 170           {                                                                   \
 171             result = GCONV_ILLEGAL_INPUT;                                     \
 172             break;                                                            \
 173           }                                                                   \
 174       }                                                                       \
 175                                                                               \
 176     *((uint32_t *) outptr)++ = ch;                                            \
 177   }
 178 #define EXTRA_LOOP_DECLS        , int set
 179 #include <iconv/loop.c>
 180
 181
 182 /* Next, define the other direction.  */
 183 #define MIN_NEEDED_INPUT        MIN_NEEDED_TO
 184 #define MIN_NEEDED_OUTPUT       MIN_NEEDED_FROM
 185 #define MAX_NEEDED_OUTPUT       MAX_NEEDED_FROM
 186 #define LOOPFCT                 TO_LOOP
 187 #define BODY \
 188   {                                                                           \
 189     unsigned char ch;                                                         \
 190     size_t written = 0;                                                       \
 191                                                                               \
 192     ch = *((uint32_t *) inptr);                                               \
 193                                                                               \
 194     /* First see whether we can write the character using the currently       \
 195        selected character set.  */                                            \
 196     if (set == ASCII_set || (ch >= 0x01 && (ch < 0x21 || ch == 0x7f)))        \
 197       {                                                                       \
 198         /* Please note that the NUL byte is *not* matched if we are not       \
 199            currently using the ASCII charset.  This is because we must        \
 200            switch to the initial state whenever a NUL byte is written.  */    \
 201         if (ch <= 0x7f)                                                       \
 202           {                                                                   \
 203             *outptr++ = ch;                                                   \
 204             written = 1;                                                      \
 205           }                                                                   \
 206       }                                                                       \
 207     else                                                                      \
 208       {                                                                       \
 209         assert (set == KSC5601_set);                                          \
 210                                                                               \
 211         written = ucs4_to_ksc5601 (ch, outptr,                                \
 212                                    (NEED_LENGTH_TEST ? outend - outptr : 2)); \
 213                                                                               \
 214         if (NEED_LENGTH_TEST && written == 0)                                 \
 215           {                                                                   \
 216             result = GCONV_FULL_OUTPUT;                                       \
 217             break;                                                            \
 218           }                                                                   \
 219         if (written == UNKNOWN_10646_CHAR)                                    \
 220           {                                                                   \
 221             /* Either this is an unknown character or we have to switch       \
 222                the currently selected character set.  The character sets      \
 223                do not code entirely separate parts of ISO 10646 and           \
 224                therefore there is no single correct result.  If we choose     \
 225                the character set to use wrong we might be end up with         \
 226                using yet another character set for the next character         \
 227                though the current and the next could be encoded with one      \
 228                character set.  We leave this kind of optimization for         \
 229                later and now simply use a fixed order in which we test for    \
 230                availability  */                                               \
 231                                                                               \
 232             if (ch <= 0x7f)                                                   \
 233               {                                                               \
 234                 /* We must encode using ASCII.  First write out the           \
 235                    escape sequence.  */                                       \
 236                 *outptr++ = SO;                                               \
 237                 set = ASCII_set;                                              \
 238                                                                               \
 239                 if (NEED_LENGTH_TEST && outptr == outend)                     \
 240                   {                                                           \
 241                     result = GCONV_FULL_OUTPUT;                               \
 242                     break;                                                    \
 243                   }                                                           \
 244                                                                               \
 245                 *outptr++ = ch;                                               \
 246               }                                                               \
 247             else                                                              \
 248               {                                                               \
 249                 char buf[2];                                                  \
 250                                                                               \
 251                 written = ucs4_to_ksc5601 (ch, buf, 2);                       \
 252                 if (written != UNKNOWN_10646_CHAR)                            \
 253                   {                                                           \
 254                     /* We use KSC 5601.  */                                   \
 255                     *outptr++ = SI;                                           \
 256                     set = KSC5601_set;                                        \
 257                                                                               \
 258                     if (NEED_LENGTH_TEST && outptr + 2 > outend)              \
 259                       {                                                       \
 260                         result = GCONV_FULL_OUTPUT;                           \
 261                         break;                                                \
 262                       }                                                       \
 263                                                                               \
 264                     *outptr++ = buf[0];                                       \
 265                     *outptr++ = buf[1];                                       \
 266                   }                                                           \
 267                 else                                                          \
 268                   {                                                           \
 269                     result = GCONV_ILLEGAL_INPUT;                             \
 270                     break;                                                    \
 271                   }                                                           \
 272               }                                                               \
 273           }                                                                   \
 274       }                                                                       \
 275                                                                               \
 276     /* Now that we wrote the output increment the input pointer.  */          \
 277     inptr += 4;                                                               \
 278   }
 279 #define EXTRA_LOOP_DECLS        , int set
 280 #include <iconv/loop.c>
 281
 282
 283 /* Now define the toplevel functions.  */
 284 #include <iconv/skeleton.c>